Pharmaceutical dosage units containing flupirtine or a pharmaceutically acceptable salt of flupirtine with controlled release of active substance using a delayed-action or controlled-release component. There are 0.001 to 20 parts delayed-action component for each part by weight flupirtine (calculated as the base) and the release rate of flupirtine is between 5 and 300 mg per hour. In some cases, the dosage units may also contain a rapidly releasing component of flupirtine or of one of its salts. The dosage units reduce the sedative effect of flupirtine.

The present invention relates to pharmaceutical dosage forms containing flupirtine with controlled release of the 5 active ingredient.
Flupirtine is a pharmaceutically active substance having the formula:
Flupirtine is useful as an analgesic. However, it sometimes causes a sedative side-effect.
The object of the present invention is to provide a solid dosage form of the pharmaceutically active substance flupirtine in which the sedative side effects of the flupirtine are largely or totally suppressed. A further object of the invention is to provide a solid dosage form of flupirtine which is useful for patients who require therapy with an analgesic which formulation does not have to be taken as frequently as in the case of conventional formulations.
The invention is particularly advantageous for patients with severe pain, e.g. tumor patients, who find the less frequent administration of drugs as well as longer duration of action to be advantageous, especially in the case of night pain. A further advantage of the invention is that the amount of active substance to be used daily takes strain off the body, especially the liver.
These and other objects are achieved by means of a pharmaceutical dosage form or pharmaceutical composition comprising or consisting essentially of flupirtine as the active substance and containing, in addition to customary adjuvants and additives, a delayed-action or controlled-release component. The composition is formulated so that the active substance flupirtine or its pharmaceutically-acceptable salts is/are released in a controlled manner and is present in an amount of 1 part by weight flupirtine, relative to the base, per 0.001 to 20 parts by weight delayed-action or controlled-release component and that the release is from 5 to 300 mg, e.g. 10 to 100 mg or also 20 to 60 mg flupirtine/hour. The pharmaceutical dosage unit may be formulated for oral administration and contain 50 to 600 mg flupirtine active substance, for parenteral use and contain 50 to 500 mg flupirtine active substance or for dermal use and contain 5 to 5000 mg flupirtine active substance.
This pharmaceutical composition with controlled release of the active substance can also be combined with an additional amount of flupirtine or of one of its pharmaceutically acceptable salts, which additional amount is formulated without the addition of delayed-action component and is rapidly released, that is, within 10 to 20 minutes. This additional amount can provide an initial phase of treatment assuring a rapid commencement of the action of the dosage form. In this manner, such a form of administration can bring about a rapidly commencing and long-lasting action, which is desirable for pain-killers. The amount of the initial phase flupirtine, i.e., without controlled-release component, in proportion to the amount of flupirtine which is released in a controlled manner, is in this instance 2:1 to 1:9 (amounts by weight in each instance, based on the amount of flupirtine base).
As indicated above, the flupirtine can be present as the free base or as a salt. Suitable salts are e.g. chloride, maleate, D-gluconate. If the flupirtine is present in the form of a salt, the amount of flupirtine, indicated above and calculated as the base, is increased corresponding to the greater molecular weight of the salt. The amounts in this description in the xe2x80x9cflupirtinexe2x80x9d indication always refers to the base and should be converted, upon the presence of a salt, in accordance with the increased molecular weight.
A further object of the invention is to provide a method for preparing a pharmaceutical composition of flupirtine which achieves controlled release of active substance, the method comprising introducing the active substance into customary adjuvants and additives and a delayed-action or controlled-release component which method is characterized in that flupirtine or its physiologically compatible salts are used in a ratio of 1 part by weight flupirtine, calculated as the base, per 0.001 to 20 parts by weight delayed-action component as active substance to be released in a controlled manner and that the release rate is adjusted to the range of 5 to 300 mg flupirtine/hour.
If the active substance flupirtine is placed in a form of administration which releases the active substance over a fairly long time period (and therewith brings about a xe2x80x9cdelayingxe2x80x9d of the effect of the active substance), the side effect of tiredness is no longer detected in persons treated with this form of administration.
The subject matter of the invention is therefore constituted by solid forms of administration with a controlled release of the active substance flupirtine or pharmaceutically salts of flupirtine. Further subject matter of the invention comprises a method of preparing a dosage form which provides controlled release of the active substance flupirtine or of pharmaceutically acceptable salts of flupirtine.
The determination of the release rate of flupirtine within the limits indicated on above is carried out in an aqueous solution with pH 1 or 6.8. The pH""es are adjusted by means of the addition of acid or by the addition of a customary buffer, e.g. a phosphate buffer. The method is described in the USP XXII, Jan. 1, 1990, pp. 1578-1579.
The following are potential examples of forms of administration: Tablets, film tablets, hard-gelatin capsules, soft-gelatin capsules, pellets, granulates, coated tablets, suppositories, microcapsules, aqueous or oily suspensions, oily solutions.
The controlled-release compositions of the invention can be obtained as follows:
1. By binding flupirtine to physiologically compatible cation exchangers. The following can be used, for example, as such cation exchangers: Acrylic and methacrylic resins with exchangeable proton, acid groups: COO, e.g. Amberlite(copyright) IRP-64 polystyrene resins with exchangeable Na, acid groups: SO3, e.g. Amberlite(copyright) IRP-69.
The ion exchangers are acidic ion exchangers. The maximum ratio of flupirtine : ion exchanger is approximately 1:1 and the minimum ratio is approximately 1 part by eight active substance per 800 parts ion exchange resin. It is preferable to use 1 to 400 parts by weight ion exchanger, quite especially 1 to 100 parts by weight ion exchanger per 1 part by weight active substance.
The binding of the flupirtine takes place by allowing a solution of flupirtine to run through a bed of the ion exchanger in a column or the ion exchanger is suspended in a solution of flupirtine, filtered off after agitation and washed. The charged ion exchanger is dried at temperatures of up to approximately 50xc2x0 C. The charged ion-exchanger particles are also preferably provided with a casing, as is described e.g. in U.S. Pat. No. 4,221,776. An advantage of the additional casing resides in the fact that the release rate of the active substance can be varied and influenced by the selection of the casing material. The drying of the charged ion-exchanger particles provided with casing can take place with warm air of 70xc2x0 C. to 90xc2x0 C.
The charged ion-exchanger particles can be filled into hard-gelatin capsules or be prepared with the aid of water and thickening agents, flavoring substances, stabilizing substances and preservatives as a suspension as form of administration.
2. The encasing of active-substance particles, granulate- or pellet grains or of tablets containing flupirtine with coatings of the following substances, which casing substances can also be used in a mixture: Hydroxypropylmethyl cellulose phthalate or -acetate succinate; cellulose-, starch- as well as polyvinyl acetate phthalate; carboxymethyl cellulose; polyvinyl acetate; methyl cellulose phthalate, methyl cellulose succinate, methyl cellulose phthalate succinate as well as methyl cellulose phthalicacid semi-ester; zein; ethyl cellulose as well as ethyl cellulose succinate; shellac; gluten; ethylcarboxyethyl cellulose; ethacrylate-maleic-acid anhydride copolymer; maleic-acid anhydride vinylmethyl ether copolymer; styrene-maleic-acid copolymers; 2-ethyl-hexyl-acrylate-maleic-acid anhydride; crotonic-acid vinyl acetate copolymer; glutamic-acid/glutamic-acid ester copolymer; carboxymethylethyl cellulose glycerol monooctanoate; cellulose acetate succinate; polyarginine; fat, oils, waxes, fatty alcohols; anionic polymers of methacrylic acid and methacrylic-acid esters (Eudragit(copyright)L, Eudragit(copyright)S); copolymers of acrylic and methacrylic-acid esters with a low content of trimethyl ammonium methacrylate (Eudragit(copyright)RL, Eudragit(copyright)RS), copolymer of acrylic acid, methacrylic acid as well as its esters (ratio of the free carboxyl groups to the ester groups e.g. 1:1) (Eudragite(copyright)L 30 D), copolymer of acrylic-acid ethyl- and methacrylic-acid methyl ester (Eudragit(copyright)NE 30 D).
The substances cited can additionally contain conventional softeners (e.g. dibutyl sebacate, citric and tartaric-acid esters, glycerol and glycerol esters, phthalic-acid esters and similar substances) and, moreover, the addition of water-soluble substances such as polyethylene glycols, polyvinyl pyrrolidone, copolymer of polyvinyl pyrrolidone and polyvinyl acetate, hydroxypropyl cellulose, hydroxypropyl methyl cellulose. The addition of solids such as talcum and/or magnesium stearate in the casing is also possible.
The pellet grains, granulate grains or tablets can also contain worked-in additives of organic acids (such as e.g. citric acid, tartaric acid, maleic, fumaric, ascorbic acid).
The encasing takes place by spraying on solutions in organic solvents or suspensions of the cited substances in organic solvents or water and even further adjuvants can be added in order to optimize their ability to be processed such as e.g. surface-active agents and pigments.
The spraying on takes place e.g. in a coating pan or in perforated pans or in an air-suspension method (e.g. Glatt fluid-bed system WLSD5). The encasing can also take place by coagulating aqueous dispersions of the above-named substances in that the active substance is mixed with the dispersion and the water removed by drying.
Coated active-substance particles and coated granulates can be pressed to form tablets, coated pellets filled into hard-gelatin capsules or pressed, after the addition of further substances, to tablets.
When coating active-substance particles or granulates containing the active-substance particles, it is customary to use more casing substance than in the case of pellets since the surface which must be covered is considerably greater than in the case of pellets.
0.001 to 20 parts by weight casing substance can be used per 1 part by weight active substance. A weight ratio of 1 part active substance and 0.005 to 10 parts by weight casing material is preferred and 0.01 to 5 parts by weight casing material for each part by weight active substance is quite especially preferred. The application of the casing substances takes place at elevated temperature, preferably in a current of air, supply-air temperature e.g. 70 to 90xc2x0 C.; temperature of the exhaust air e.g. up to 40xc2x0 C.
3. The encasing of compacts, tablets and granulates containing flupirtine and one or more osmotically active substances (e.g. mannitol, sorbitol) with a semipermeable membrane, e.g. consisting of 70 to 90 % by weight cellulose acetate and hydroxypropylmethyl cellulose (30 to 10 % by weight).
The following can also be considered as potential osmotically active substances: Organic and inorganic compounds or soluble substances which generate an osmotic pressure gradient vis-a-vis the external liquid via the semipermeable wall. Osmotically active agents or osmotically active compounds comprise magnesium sulfate, magnesium chloride, sodium chloride, lithium chloride, potassium sulfate, potassium hydrogen phosphate, urea, saccharose and the like. Further osmotically active agents are known from U.S. Pat. Nos. 3,854,770; 4,077,407 and 4,235,236.
The following, for example, can be considered as potential semipermeable materials which are known as polymers for osmosis and reverse osmosis: Cellulose acylate, cellulose diacylate, cellulose triacylate, cellulose acetate, cellulose diacetate, cellulose triacetate, xcex2-glucan acetate, acetaldehyde dimethyl acetate, cellulose acetate ethyl carbamate, polyamide, polyurethane, sulfonated polystyrene, cellulose acetate phthalate, cellulose acetate methyl carbamate, cellulose acetate succinate, cellulose acetate dimethyl amino acetate, cellulose acetate chloroacetate, cellulose dipalmitate, cellulose dioctanoate, cellulose dicaprylate, cellulose dipentanate, cellulose acetate valerate, cellulose acetate-p-toluene sulfonate, cellulose acetate butyrate, ethyl cellulose, selectively permeable polymers formed by means of the common precipitation of a polycation and of a polyanion as indicated in U.S. Pat. Nos. 3,173,876; 3,276,586; 3,541,005; 3,541,006 and 20 3,546,142. Such encasings in semipermeable membranes can also take place e.g. in accordance with published German Patent Applications DE-A 33 10 081 (U.S. Pat. No.4,449,983) or DE-A-33 10 096 (U.S. Pat. No. 4,455,143).
The amount of osmotically active substance can be, for each part by weight flupirtine, from 1 to 20 parts by weight, preferably 2 to 6 and quite especially preferably 4 to 5 parts by weight. The casing substances are applied in such an amount that the semipermeable membrane is 50 to 500 xcexcm thick, preferably 100 to 300 xcexcm thick.
The processing of the active substance and of the osmotically active substances can take place between room temperature and 80xc2x0 C. In order to adjust the release rate, the matter is dried e.g. at 70-90xc2x0 C. supply-air temperature.
If required, the semipermeable membrane can also contain a microporous layer or microporous substances can be worked in (cf. German Offenlegungsschrift 33 10 081 (U.S. Pat. No. 4,455,143), e.g. pages 7-17 of the German text).
Materials suitable for producing the microporous layer comprise e.g. polycarbonates of linear polyesters of carbonic acid in which carbonate groups recur in the polymer chain, microporous materials produced by phosgenation of a dihydroxy aromatic compound such as bisphenol, a microporous polyvinyl chloride, microporous polyamides such as polyhexamethyl adipic acid amide (nylon 66), microporous modacrylic polymers including those formed from polyvinyl chloride and acrylonitrile, microporous styrene acrylic monomers and their copolymers, porous polysulfones characterized by the presence of diphenylene sulfone groups in a linear chain, halogenated or of an anhydride with an alkylene polyol, polyalkyl sulfides, phenolic polymers, polyesters, microporous polysaccharides with substituted anhydro glucose units exhibiting a decreasing permeability for water and biological liquids, asymmetric porous polymers, cross-linked olefin polymers, hydrophobic or hydrophilic microporous homopolymers, copolymers or interpolymers with a reduced density as well as materials described in U.S. Pat. Nos. 3,595,752; 3,643,178; 3,654,066; 3,709,774; 3,718,532; 3,803,601; 3,852,224; 3,852,388 and 3,853,601, in British Patent 1,126,849 and in Chemical Abstracts, vol. 71, 427F and 22573F (1969).
Further microporous materials for producing the microporous layer comprise polyurethanes, cross-linked chain-lengthened polyurethanes, polyimides, polybenzimidazoles, collodium, regenerated proteins, semisolid cross-linked polyvinyl pyrrolidone, microporous materials produced by diffusion from polyvalent cations in polyelectrolyte sols, microporous derivatives of polystyrene such as sodium polystyrene sulfonate, polyvinyl benzyl trimethyl ammonium chloride, microporous cellulose acylates and similar microporous polymers which are known from U.S. Pat. Nos. 3,524,753; 3,565,259; 3,276,589; 3,541,055; 3,541,006; 3,546142; 3,615,024; 3,646,178 and 3,852,224.
The pore-forming materials suitable for producing the microporous layer comprise solids and pore-forming liquids. The expression xe2x80x9cpore-forming materialxe2x80x9d, as it is used here, also includes substances which form micropassages and the removal of the pore-forming materials can result in both types. The expression xe2x80x9cpore-forming liquidsxe2x80x9d includes semisolid and viscous liquids in the framework of this description. The pore-forming materials can be inorganic or organic and the layer-forming polymer generally contains 5 to 70% by weight pore-forming materials, especially 20 to 50% by weight. The expression xe2x80x9cpore-forming materialxe2x80x9d comprises, both for solids and for liquids, substances which can be dissolved out of, extracted or leached out of the precursor of the microporous membrane by the liquid present in the application environment with formation of an effective, open-cell, microporous layer. The pore-forming solids have a particle size of approximately 0.1 to 200 xcexcm and comprise alkali salts such as lithium carbonate, sodium chloride, sodium bromide, potassium chloride, potassium sulfate, potassium phosphate, sodium acetate, sodium citrate and the like. Organic compounds such as saccharides including the sugars saccharose, glucose, fructose, mannitol, mannose, galactose, sorbitol and the like. Soluble polymers such as carbo waxes, Carbopol(copyright) and the like can also be used. The pore-forming materials also include diols, polyols, polyvalent alcohols, polyalkylene glycols, polyglycols, poly(xcex1-xcfx89)-alkylene diols and the like.
4. The embedding of flupirtine and flupirtine salts or the binding to the following substances or mixtures of these substances:
Digestible fats, e.g. triglycerides of saturated fatty acids C8H16 O2 to C18H36O2 and their mixtures, peanut oil and hydrated peanut oil, castor oil and hydrated castor oil, olive oil, sesame oil, cottonseed oil and hydrated cottonseed oil, corn oil, wheat germ oil, sunflower seed oil, cod liver oil, mixtures of mono-, di-, triesters of palmitic and of stearic acid with glycerol, glycerol trioleate, diglycol stearate, stearic acid, metal salts of fatty acids, especially alkaline-earth salts of fatty acids, e.g. magnesium stearate.
Indigestible fats and fat-like substances, e.g. esters of aliphatic saturated or unsaturated fatty acids (2 to 22 carbon atoms, especially 10 to 18 carbon atoms) with monovalent aliphatic alcohols (1 to 20 carbon atoms), carnauba wax, beeswax, fatty alcohols (straight-chain or branched-chain) with the empirical formula C8,H7OH to C30H61OH, especially C12H25OH to C24H49OH.
Polymers such as polyvinyl alcohol, polyvinyl chloride, polyacrylic acid (Carbopol(copyright)); anionic polymers of methacrylic acid and methacrylic acid esters (Eudragit(copyright)L, Eudragit(copyright)S), acrylic and methacrylic acid ester copolymers with trimethyl ammonium methacrylate (Eudragit(copyright)RL, Eudragit(copyright)RS) copolymer from acrylic acid ethyl and methacrylic acid methyl esters (Eudragit(copyright)NE 30 D), as well as from acrylic acid, methacrylic acid as well as their esters (ratio of the free carboxyl groups to the ester groups 1:1) (Eudragito(copyright)- L 30 D), polyethylene, polyglycolic acid, polyhydroxy butyric acid, polylactic acid, copolymers of lactic acid and glycolic acid (producer: Boehringer Ingelheim), copolymers of lactic acid and ethylene oxide, copolymers of glycolic acid and ethylene oxide, copolymers of lactic acid and hydroxy butyric acid, hydroxypropylmethyl cellulose phthalate or acetate succinate; cellulose acetate phthalate, starch acetate phthalate as well as polyvinyl acetate phthalate; carboxymethyl cellulose; methyl cellulose phthalate, -succinate, -phthalate succinate, methyl cellulose phthalic acid semi-ester; zein; ethyl cellulose; shellac, gluten; ethyl carboxyethyl cellulose; ethyl acrylate-maleic-acid anhydride copolymer; maleic-acid anhydride vinylmethyl ether copolymer; styrene-maleic-acid copolymers; 2-ethyl-hexyl-acrylate-maleic-acid anhydride; crotonic-acid vinyl acetate copolymer; glutamic acid/glutamic-acid ester copolymer; carboxymethylethyl cellulose glycerol monooctanoate; cellulose acetate succinate; polyarginine; cross-linked alginate; cross-linked gelatins;
Swellable substances such as methyl cellulose, hydroxypropyl cellulose, hydroxypropylmethyl cellulose (Pharmacoat, Methocel E=propylene glycolic ether of methyl cellulose), alginic acid and its salts (Na-, Ca salt, also mixtures of sodium alginate and calcium salts, e.g. CaHPO4), starch, carboxymethyl starch, carboxymethyl cellulose and its salts (e.g. Na salt), galactomannan, gum arabic, karaya gum, gum ghatti, agar-agar, carrageen, xanthan gum, guar gum and its derivatives, carob-seed meal, propylene glycol alginate, pectin, tragacanth.
In these delayed-action components 0.001 to 20 parts by weight delayed-action component, preferably 0.5 to 10 parts by weight and quite especially preferably 1.0 to 5 parts by weight are used for each part by weight flupirtine. The production of these preparations takes place at temperatures between 18xc2x0 C. and 80xc2x0 C.
The production of this form of administration can take place:
a) By dissolving or dispersing flupirtine or its salts in the cited fats or fat-like substances or mixtures thereof, even with melting of the cited substances and subsequent re-cooling, comminution, possible addition of further substances such as e.g. the above-mentioned substances which are water-soluble or swellable in water and pressing into tablets. The cooling off of the melt and comminution can also be combined in one step in that the melt is dispersed in cold water or is subjected to a spray drying. When the above-mentioned oils are used as retarding agent, flupirtine or its salt is dissolved or suspended in the oil and, if required, after the addition of up to 2% aluminum monostearate, filled into ampoules and subsequently sterilized or, if required, homogenized after the addition of flavoring substances and/or sedimentation retarders such as highly disperse silicon dioxide (e.g. Aerosilo) and dispensed into bottles;
b) By mixing flupirtine or its salts with the cited fats, polymers or swellable substances or mixtures of these substances, also with the use of heat, and pressing the mixtures, if required, after the addition of further adjuvants to tablets or forming to pellets;
c) By mixing flupirtine or its salts with solutions of the cited fats or polymers in water or organic solvents such as e.g. ethanol, ethyl acetate, acetone or isopropanol, if required, mixing with carrier materials such as cellulose, as well as subsequent evaporation of the solvent and mixing the embedded active-substance obtained in this way with further adjuvants and processing to formed materials such as e.g. tablets or pellets;
d) By moistening a mixture of flupirtine or its salts and the cited swellable substances with organic solvents such as ethanol, ethyl acetate, acetone or isopropanol, if required, with the addition of binders such as polyvinyl pyrrolidone or copolymers of polyvinyl pyrrolidone and polyvinyl acetate, granulating the mixture obtained, subsequent drying, the addition of possibly further adjuvants and pressing the mixture to tablets;
e) By mixing flupirtine or its salts with a solution of natural or artificial resins such as shellac or polyvinyl acetate in polyethylene glycol with a molar weight of 200 to 1500, the possible addition of further adjuvants such as e.g. stearates or swellable substances and the encapsulation of the mass obtained in solid or hard-gelatin capsules.
In general, the production of the dosage units takes place in a known manner; in addition to the delayed-action components the known and customary pharmaceutical adjuvants as well as other customary carriers and diluting agents can be used. The adjuvants cited as delayed-action component can also perform other functions, e.g. as mold-release agents or as disintegrants.
Those substances can be considered as such carriers and adjuvants, for example, which are recommended or indicated in the following literature as adjuvants for pharmacy, cosmetics and related areas: Ullmanns Encyklopadie der technischen Chemie, vol 4 (1953), pp. 1 to 39; Journal of Pharmaceutical Sciences, vol 52 (1963), pp. 918 ff.; H.v. Czetsch-Lindenwald, Hilfsstoffe fur Pharmazie und angrenzende Gebiete; Pharm. Ind., No. 2, 1961, pp. 72 ff.; Dr. H. P. Fiedler, Lexikon der Hilfsstoffe fxc3xcr Pharmazie, Kosmetik und angrenzende Gebiete, 3d edition, Editor Cantor, Aulendorf in Wurttemberg.
Examples of customary adjuvants, carriers and diluting agents are gelatins, natural sugars such as cane sugar or lactose, lecithin, pectin, starch (e.g. corn starch) as well as starch derivatives, cyclodextrins and cyclodextrin derivatives, polyvinyl pyrrolidone, gelatins, gum arabic, alginic acid, tylose, talcum, lycopodium, silica (e.g. colloidal), levulose, tragacanth, sodium chloride, stearates, magnesium salts and calcium salts of fatty acids with 12 to 22 carbon atoms, especially of the saturated ones (e.g. stearates), polyethylene glycol with an average molecular weight between 200 and 20,000, preferably between 200 and 5,000, especially between 200 and 1,000 or their mixtures and/or polymers of vinyl pyrrolidone and/or mixed polymers of vinyl pyrrolidone and vinyl. acetate. Esters of aliphatic, saturated or unsaturated fatty acids (2 to 22 carbon atoms, especially 10 to 18 carbon atoms) with monovalent, aliphatic alcohols (1 to 20 carbon atoms) or polyvalent alcohols such as glycols, glycerol, diethylene glycol, pentaerythritol, sorbitan, mannitol, etc., which can also be etherified, if required, benzyl benzoate, dioxolanes, glycerol formals, tetrahydrofurfuryl alcohol, polyglycol ether with C1 to C12 alcohols, dimethyl acetamide, lactamides, lactates, ethyl carbonates, silicones (especially polydimethyl siloxanes of average viscosity), calcium carbonate, sodium carbonate, calcium phosphate, sodium phosphate, magnesium carbonate, gum arabic, alginic acid, stearates, fats and substances with a similar action.
In addition, the dosage units can contain surface-active substances. The following are named by way of examples: alkali soaps such as alkali salts of higher fatty acids (e.g. Na-palmitate, Na-stearate) or their derivatives (e.g. Na-ricinoleate sulfate ester); sulfonated compounds or sulfonated compounds which arise by means of the conversion of higher fatty alcohols with sulfuric acid or chlorosulfonic acid and are used e.g. as sodium salts (e.g. sodium lauryl sulfate, sodium cetyl sulfate, sodium stearyl sulfate, sodium cetyl sulfonate); salts of bile acids; saponines; quaternary ammonium compounds; partial fatty-acid esters of sorbitan; partial fatty-acid esters and fatty-acid esters of polyoxyethylene sorbitan; polyoxyethylene sorbitan ethers; polyoxyethylene fatty-acid esters; polyoxyethylene fatty alcohol ethers; fatty-acid esters of saccharose; fatty-acid esters of polyglycerol; proteins; lecithins.
The forms of administration can also contain celluloses, especially if compressed tablets are to be produced. The following are potential candidates: Purified cellulose (e.g. as commercial Elcema(copyright)) or microcrystalline cellulose, e.g. as is commercially marketed under the name Avicelo. However, other fillers with a binder function can also be used such as calcium hydrogen phosphate, lactose, starches (e.g. potato starch, corn starch, modified starches such as starch ST 1500/Colorcon), glucose, mannitol, saccharose. Moreover, the forms of administration can contain sedimentation retarders such as e.g. highly disperse silicas having a surface of 50 to 500 m2/g especially 100 to 400 m2/g (determined according to the BET method). They are commercially available, e.g. under the name of Aerosil(copyright).
In addition, the use of form-separating agents in the dosage units can be logical. The following can be cited as such agents: Talcum or siliconized talcum, calcium- and magnesium stearate, stearic acid, paraffin, hydrogenated fats and oils, silicon-oil emulsion.
Substances can also be considered as further adjuvants which bring about, e.g., tablet fragmentation, (so-called disintegrants) such as: Cross-linked polyvinyl pyrrolidone, sodium carboxymethyl starch and ultraamylopectin.
For the production of solutions and suspensions, e.g., water or physiologically compatible organic solvents such as e.g. ethanol, 1,3-propylene glycol, polyglycols and their derivatives come into consideration. For injectable solutions or suspensions, e.g. non-toxic, parenterally compatible diluting agents or solvents such as e.g. water, 1,3-butane diol, ethanol, 1,3-propylene glycol, polyglycols in a mixture with water, Ringer""s solution, isotonic solution of common salt can be considered.
Moreover, the addition of stabilizers, colorants, antioxidants and complexing agents (e.g. ethylenediamine tetraacetic acid) and the like is possible as well as the addition of acids such as citric acid, tartaric acid, maleic acid, fumaric acid.
The following, for example, can be used as antioxidants: Sodium metabisulfite, cysteine, ascorbic acid and its esters (e.g. -palmitate), flavonoids, bile acid, bileacid alkyl ester, butylhydroxy anisol, nordihydroguaiaretic acid, tocopherols as well as tocopherols+synergists (substances which bind heavy metals by complex formation, e.g. lecithin, ascorbic acid, citric acid phosphoric acid).
Possible preservatives are e.g. sorbic acid, phydroxybenzoic-acid esters (e.g. low-alkyl ester), benzoic acid, sodium benzoate, trichloroisobutyl alcohol, phenol, cresol, benzethonium chloride and formalin derivatives.
The following can be considered as plasticizers for casing substances: Citric- and tartaric-acid esters (acetyl triethyl-, acetyl-tributyl-, tributyl-, triethyl-citrate); glycerol and glycerol esters (glycerol diacetate, -triacetate, acetylated monoglycerides, castor oil); phthalic-acid esters (dibutyl-, diamyl-, diethyl-, dimethyl-, dipropyl-, D-(2-methoxy- or ethyoxyethyl)-phthalate, ethylphthalyl- and butylphthalylethyl- and butylglycolate); alcohols (propylene glycol, polyethylene glycol of different chain lengths), adipates (diethyl-, di(l-methoxy- or ethoxyethyl)adipate); benzophenone; diethyl- and dibutyl sebacate, -succinate, -tartrate; diethylene glycol dipropionate; ethylene glycol diacetate, -dibutyrate, -dipropionate; tributyl phosphate, tributyrin; polyethylene glycol sorbitan monooleate; sorbitan monooleate.
For applying the delayed-action components and/or casing substances, solvents can be used from the group of aqueous solvents, alcohols, ketones, esters, ethers, aliphatic hydrocarbons, halogenated solvents, for example, among others, acetone, diacetone alcohol, methanol, ethanol, isopropyl alcohol, butyl alcohol, methyl acetate, ethyl acetate, isopropyl acetate, n-butyl acetate, methylisobutyl ketone, methylpropyl ketone, n-hexane, ethyleneglycolmonoethyl ether, ethylene glycol monoethyl acetate, methylene dichloride, ethyl dichloride, propylene dichloride, carbon tetrachloride, nitroethane, nitropropane, tetrachloroethane, ethyl ether, isopropyl ether, cyclohexane, cyclooctane, benzene, toluene, naphtha, 1,4-dioxane, tetrahydrofuran, diethylene glycol dimethyl ether, water and their mixtures such as acetone and water, acetone and methanol, acetone and ethyl alcohol, methylene dichloride and methanol and ethylene dichloride and methanol as well as their mixtures. These solvents are removed again during the course of the encasing process.
Independently of the method of production, the forms of administration of the invention release the active substance flupirtine or its physiologically compatible salts at a release rate between 5 and 300 mg per hour to body fluids or pass into the latter.
Dosing indications always refer to flupirtine as base; if salts of flupirtine are used, a conversion in accordance with the molar weight should be made.
The contents of flupirtine in the dosage units of the invention are:
10 mg-3000 mg, preferably
20 mg-2000 mg
10 50 mg-1500 mg.
The individual doses cited can be used 1-5 times, preferably 1-3 times, especially 1-2 times daily.
In general, a release rate from a tablet or capsule of 20-30 mg flupirtine per hour desirable.

Oral forms of administration containing solid flupirtine with controlled release of active substance


An apparatus for detecting a heart sound of a living subject, including a pressure-pulse-wave sensor which is adapted to be worn on a body portion of the subject that is distant from a chest of the subject, detects a pressure pulse wave produced by an artery of the body portion, and generates a pressure-pulse-wave signal representing the detected pressure pulse wave; and a heart-sound extracting device for extracting, from the pressure-pulse-wave signal generated by the pressure-pulse-wave sensor, a heart-sound component representing the heart sound of the subject.

1. Field of the Invention
The present invention relates to an apparatus and a method for detecting a heart sound of a living subject, at a position distant from a chest of the subject.
2. Related Art Statement
Heart sounds are used to make a diagnosis of heart-valve disease or congenital heart disease. In addition, heart sounds may be used to obtain pulse-wave-propagation-velocity-relating information such as a pulse-wave propagation needed for a pulse wave to propagate through an artery between two body portions of a living subject, or a pulse-wave propagation velocity at which a pulse wave propagates through an artery.
It has been a conventional manner to detect heart sounds using a microphone. Since heart sounds are vibrations, blood-flow sounds, etc. produced when the valves of the heart open and close, the heart-sound microphone is usually put on the skin of the chest (in particular, the skin right above the heart).
Therefore, when the heart-sound microphone is put on, it is needed to take off cloths to expose the chest. Thus, putting on the heart-sound microphone is more cumbersome than putting on a sensor on an arm or a neck.
Meanwhile, obtaining pulse-wave-propagation-velocity-relating information needs detecting respective heartbeat-synchronous signals at two body portions of a living subject. Therefore, in the case where the heart sound detected by the microphone put on the chest is used as one of the two heartbeat-synchronous signals needed to obtain the pulse-wave-propagation-velocity-relating information, it is disadvantageously needed to put on another sensor on the subject so as to detect the other heartbeat-synchronous signal.

Heart-sound detecting apparatus and heart-sound detecting method


The inventive device consists of a disk which can be rotated around a central axis, a wobble pin which is mounted in the disk so that can rotate around an axis which is arranged at an angle in relation to the plane, of said disk, a swivel pin which is secured to the wobble pin at an angle in relation to the axis thereof, and a fastening device which prevents the swivel pin from rotating around the axis of the disk. This mechanism forms a gear enabling a rotational unidirectional movement to be translated into a back-and-forth movement in applications where limited height is available. The preferred area of application is in implantable blood pumps.

The invention concerns a device, in particular a pump, for the conversion of a unidirectional rotational motion into a reciprocating back and forth motion.
A particularly well-known device for such operations is an eccentric disc, whose cam sits in an elongated slot in a laterally displaceable guided part. The laterally guided element moves back and forth with reciprocating motion reflecting a sinusoidal contour as a result of the rotation of the eccentric disc.
Devices are known from DE-A-3 811 820 and EP-A-0 768 408 in which an offset element is used These devices have axes which intersect at a point in space for kinematic reasons. For structural reasons when using an offset element, this point of intersection cannot lie within the area of the a offset element. Consequently a relatively large structure results, which is disadvantageous for many applications. The known devices are suited for converting rapid rotational motion stabilised by a flywheel into relatively small reciprocating back and forth motion. However, the known systems are unsuitable particularly when strong lift accompanied by a relatively small rotational motion with relatively large moment is to be produced.
The invention thus has the object of presenting a new device of the above mentioned type which, above all, requires only limited height.
This object is solved with a device according to a type which possesses the following: a disc which can be rotated about a central axis, a wobble pin which is mounted in the disc so that it can rotate around an axis which is arranged at an angle in relation to the plane of said disc, a swivel pin which is secured to the wobble pin at an angle in relation to the axis thereof, and a fastening device which prevents the swivel pin from rotating around the axis of the disc.
A particularly simple arrangement, especially for the use of the device as a pump, has the movement of the pressures plate guided by a diaphragm. The diaphragm permits movement of the pressure plate in a specified range and can at the same time serve as a seal for a pressure plate functioning as a piston.
An advantageous arrangement of the invention provides for the diaphragm to be fixed to the casing. In this way, firstly, the space of the moving components is sealed and, secondly, the diaphragm is fixed in a simple manner.
It is advantageous if the diaphragm forms the boundary of a pump chamber with a part of the casing. This permits a compact design of a device built as a pump, in which the pump together with its drive and transfer mechanism, has extremely limited height.
A preferred use of the device is when it is used to pump blood. Due to the reduced height of the device, not only can it be comfortably worn on the body, but it is also suitable for implantation in the thorax as a result of its reduced height.
The described device is particularly suitable for implantable pulsating heart support systems which can also be introduced into children and small adults. The device can either be implanted or used extracorporeally.
The device is also suitable in general for the conversion of a circular rotation into a perpendicular oscillating rotation with angle xc3x8 and is particularly suitable for the unfolding or technical structures such as, for example, brake flaps on aeroplane wings, landing gear made of thin walled structures etc.
A further advantage of the device of the invention is in the self-limiting angle setting of technical structures, thus favouring its use, for example, in limbs of robots, back rests of seats, truck rear mirrors, metal leads in distribution systems, air vents, ship rudder systems and so on. In these cases the device maintains its preset position in the event of a power interruption.
With small values of set angle ranges "psgr", very high power reduction ratios are possible if required, and the device can be operated manually or remotely using notched belts, V belts or linkages.

Device for conversion of a unidirectional rotational motion into reciprocating back and forth motion and pump device comprising same


A method for estimating the frequency of a time signal by means of a discrete Fourrier transformation and interpolation between support points of the DFT spectrum. According to said method, the hamming window is used in a known manner for filter and the interpolation is carried out according to the mathematically calculated solution. The method makes use of the pact that a function of the third degree which can serve as correction distance has a clear solution within the definition range of the amount ration between a secondary maximum and a primary maximum of the DFT spectrum. The correction distance is calculated according to this solution on the basis of the ratio of the secondary maximum and the primary maximum.

1. Field of the Invention
The invention relates to a method for estimating the frequency of a time signal through the use of a Discrete Fourier Transform (DFT) and interpolation between sample points of the DFT spectrum.
2. Description of the Related Art
Examples of methods for estimating frequency utilizing a Fourier Transform are used, for example, in FM CW (Frequency Modulated, Continuous Wave) Radar systems. The use of FM CW principals for level measurement is described by Dr. J. Olto in xe2x80x9cMickrowellensensor zur Fxc3xcllstandsmessungxe2x80x9d (Microwave sensor for level measurement), Sensoren-Technologie und Anwendungen, VDI Berichter 939, 1992, pages 95-100, and in xe2x80x9cMikrowellen messen Fxc3xcllstxc3xa4ndexe2x80x9d in Design and Electronik-Sensortechnik, May 1997, issue 10, pages 40-44. The same author describes digital methods for frequency determination of single and multi-frequency signals utilizing various methods of interpolation of the Fourier spectrums. By using interpolation a vastly more accurate distance measurement made through frequency estimations can result. Shown are for example interpolation using averaging or by parabolic approximation.
A process for estimating the frequency of a time signal using Fourier Transform and the interpolation between support points of the discrete Fourier transformation using a Hamming windowing is described in xe2x80x9cHighly Accurate Frequency Interpolation of Apodized FFT Magnitude-Mode Spectra,xe2x80x9d by Goto in Applied Spectroscopy, Vol. 52, Nr.1, 1998, page 134 et seq.
Evaluation methods for precision distance measurement with FM CW systems and their use in the microwave field are described by Stolle, Heuerman and Schiek in tm-Technishes Messen 62 (2/95), pages 66-73.
Methods for accurate frequency estimation of a Fourier transformed time signal through interpolation are described by Jain, Collins and Davis in xe2x80x9cHigh-Accuracy Analog Measurements via Interpolated FFTxe2x80x9d IEEE Vol. IM-28, No. 2, June 1979, pages 1213-122 and by Grandke in xe2x80x9cInterpolation Algorithms for Discrete Fourier Transforms of Weighted Signals,xe2x80x9d IEEE Vol. IM-32, No. 2, June 1983, pages 350-355.
Further methods of frequency estimation can be found in xe2x80x9cCalculation of Narrow-Band Spectra by Direct Decimationxe2x80x9d by Liu and Mintzer in IEEE Transactions, Vol. ASSP-26, No. 6, December 1978, pages 529 through 534; and in xe2x80x9cSome Aspects of the Zoom Transform,xe2x80x9d by Yip in IEEE Transactions on Computers, Vol. C-25 No. 3, March 1976, pages 297 through 296.
The precise frequency measurement is carried out by the known Fourier-spectrum synthesis methods primarily accomplished through interpolation formula for the signal filtering through rectangular- or Hanning-windowing functions that are describable as simple equations. The Hanning interpolation formula can also be described as a signal with Hamming windowing under the assumption of an infinite expansion of a complex time signal and accepting the systematic errors of that formula.
The invention is based upon providing a method of frequency estimation that is advantageous with regards to frequency accuracy and processing expense.
The method of the invention takes advantage of the well known advantageous spectral characteristics of the Hamming window function and in particular allows an increase of the precision of a frequency estimate using a single detection with less complexity by not requiring insertion of the numerical method for the determination of the interpolation size. In particular, the invention may be represented as a closed end solution of a systematically correct equation for infinitely long real mono-tone signals as an approximation of real signals of finite length.
With the method of the invention, there are no further required approximations for the determination of the interpolation size, for instance through iterative, numerical evaluation of an interpolation rule. The off-line construction of interpolation weights, whose tabular arrangement is certainly possible and advantageous, the closed form solution algorithm will preferably be carried out as an online calculation with a default. By default, a tabular evaluation is more advantageously the maximum deviation of the stored values dependent upon the solution determined from the ratios a from adjacent maximum to high-maximum and is preferably smaller than the m-th part of the maximum values of the interpolation size with m being the number of the solution increment of the defined range of xcex1.
The invention is further illustrated below by derivation and presentation of a preferred algorithm.
For the sake of simplicity, a single frequency timing signal of frequency f0 will be examined as a discrete time signal, which is inside of a limited time window of length Nxc2x7TA in the form of N discrete sample values s(k) with a distance of the sampling period TA.
s(k)=Vxc2x7sin(2xcfx80ƒ0xc2x7kxc2x7TA+"PHgr")0xe2x89xa6kxe2x89xa6Nxe2x88x921
with V defined to be the amplitude and "PHgr" defined to by the initial phase (k=0). The generalized cosine window       w              (      i      )        =      a    -                            (                      1            -            a                    )                ·        cos                          xe2x80x83                          (                  2                                π            ·                          i              N                                      )
xe2x80x83of the Hamming window function with a=0.54 has the Fourier transform function:       W              (      k      )        =      N    ·          (                                                  -                                                1                  -                  a                                2                                      ·            δ                                          xe2x80x83                                          (                          k              +              1                        )                          -                                                            1                =                a                            2                        ·            δ                                          xe2x80x83                                          (                          k              -              1                        )                              )
xe2x80x83with k as the discrete sample (bin) of the spectrum and xcex4 being the dirac-delta function.
Through the convolution of the Fourier-transform of the Hamming window function W(k) with the timing signal s(k) and application of the discrete Fourier Transform, one obtains the DFT-spectrum Sw(i) which is the Hamming window weighted time signal with i as the number of the discrete sample (or bin) of the spectrum.
As a rule, the frequency f0 of the timing signal does not exactly match the frequency of the discrete frequency bin of the DFT spectrum fi=il(N*TA). For the frequency f0 which is not known a priori, many lines will result in the DFT spectrum, with a highest maximum at i=l as the highest value line and one of the adjacent (largest) neighboring maximum appears at i=l+1 or i=lxe2x88x921. The sought after frequency f0 lies in the frequency interval between sample (or bin) i=lxe2x88x921 and sample (or bin)i=l+1 at a correction distance d from the main line i=l according to f0=xcex* (N*TA) with xcex=l+d and xe2x88x921xe2x89xa6dxe2x89xa6+1, where d will also be denoted as a sub-bin.
Preferably the more exact frequency estimate based upon the correction distance calculation will be based upon the size of the highest maximum Sw(i) and the size of the adjacent maximum Sw(ixc2x11). Preferably, the ratio of these two sizes   α  =            |                        S          w                                  (                      l            ±            1                    )                    |              |                        S          w                                  (          l          )                    |
xe2x80x83will be formed, which is in the range of 0xe2x89xa6xcex1xe2x89xa61. For the application of these ratios as an aid, the relation is more advantageously derived for the solution of the correction distance d,   α  =            |                        (                                    -              2                        +                          4                            d                        -                          2                                            d                2                                      +                          a              ·                              (                                                      -                    2                                    -                                      8                                        d                                    +                                      4                                                              d                      2                                                                      )                                              )                ·                  (                      d            +            1                    )                    |              |                                    -            2                              d                +                  a          ·                      (                                          4                                                  d                  2                                            -              2                        )                    ·                      (                          d              -              2                        )                              |
xe2x80x83which can be simplified by merely making small angle approximations. According to the definition of the Hamming window, a=0.54 and the prominent relation for xcex1 transforms itself into the third degree equation
d3(0.16xcex1+0.16)+d2(xe2x88x920.32xcex1xe2x88x920.16)+d(xe2x88x921.08xcex1xe2x88x921.24)+2.16xcex1xe2x88x920.92=0
This equation advantageously represents a closed end solution for the defined region of xcex1 (0xe2x89xa6xcex1xe2x89xa61), according to which the calculation of the correction distance will be preferably realized. The introduction of an aid to simplify notation results in the closed end solution for   d  =            x      3        -                  a        2            2
where       x    =                  -        2            ·                                    |                          p              3                        |                                                        ·              cos                                                  xe2x80x83                                                  (                                                ϕ                  3                                +                                  π                  3                                            )                                                ϕ    =          arccos                    xe2x80x83                          (                              -                          q              2                                ·                                    (                                                |                  p                                                        |                    3                                                  3                            )                                      )                  p    =                  a        1            -                        1          3                                  a          2          2                          q    =                            2          27                                  a          2          3                    -                        1          3                                  a          1                                  a          2                    +              a        0                        a      0        =                  (                              2.16                                      xe2x80x83                                    α                    -          0.92                )            c                  a      1        =                  (                                            -              1.08                                                  xe2x80x83                                    α                    -          1.24                )            c                  a      2        =                  (                                            -              0.32                                                  xe2x80x83                                    α                    -          0.16                )            c            c    =                  0.16                          xe2x80x83                        α            +              0.16        .
The prominent equation for d forms an analytical and definite solution for the problem of the interpolation between sample points (or bins) of the DFT spectrum with a Hamming Window function filtered time signal on the basis of the ratios of the highest maximum and its adjacent maximum.
The sequence of Sw(l) for the highest maximum and Sw(l+1) for the adjacent maximum forms the basis for the derivation of the solution for d. When the location of the adjacent maximum is i=lxe2x88x921, the accurate estimation of the frequency is xcex=l+d, merely the sign of the ascertained value for the correction distance d is inverted.

Method for estimating the frequency of a time signal


A method of treating autoimmune diseases is provided which involves administering an effective amount of allogeneic mononuclear cells or a molecule derived from these cells to an individual suffering from an autoimmune disease. Also provided are compositions for the treatment of autoimmune diseases.

Tens of millions of people in the United States suffer from rheumatoid arthritis (RA) or a related disease. While arthritis results in significantly fewer deaths as compared to cancer and cardiovascular diseases, there is no other group of diseases that causes so much suffering in so many people for such a prolonged period of time. Because of the tendency for arthritis sufferers to become disabled and even permanently crippled, this group of diseases is extremely important both socially and economically. There is presently no satisfactory cure for rheumatoid arthritis because its cause is unknown. In addition, many of the therapeutic agents administered to alleviate pain and inflammation associated with the disease, such as disease-modifying antirheumatic drugs (DMARDs) and non-steroidal anti-inflammatory agents (NSAIDs), produce intolerable side effects.
The understanding of the RA disease process has been considerably enhanced by the application of molecular immunology techniques. It is now generally accepted that rheumatoid arthritis represents a multifactorial disease with environmental factors (infectious agents or toxins), genetic susceptibility, and immune or autoimmune responses playing inter-connected roles. After initiation of the disease process, it is believed that activated T cells and their products are responsible for the progressive destruction of articular cartilage and sub-chondral bone that is characteristic of rheumatoid arthritis.
Advances in the understanding of the immunopathogenesis of rheumatoid arthritis have been coupled with immunologic strategies for treatment. Immunologic approaches to the treatment of rheumatoid arthritis are important and desirable given the potential toxicities associated with most remittive therapy in use today and the continued poor prognosis of rheumatoid arthritis despite aggressive drug treatment.
Monoclonal anti CD4 antibodies have been used in the treatment of rheumatoid arthritis (Reiter et al., Arthritis Rheum. 1991, 34, 525-536; Horneff et al., Arthritis Rheum. 1991, 34, 129-140; Herzog et al., J. Autoimmunity 1989, 2, 627-642; Goldberg et al., J. Autoimmunity 1991, 4, 617-630). In these studies, involving approximately 30 patients, objective and subjective improvement was noted in nearly all cases.
Another study employed chimeric monoclonal antibody to CD4 to treat 25 patients with refractory rheumatoid arthritis (Moreland et al., Arthritis Rheum. 1993, 36, 307-318) and again, some beneficial effects were observed.
Immunotherapeutic approaches have also included leukapheresis, (Karsh et al., Arthritis Rheum. 1981, 24, 867-873; Wallace et al., Arthritis Rheum. 1979, 22, 703-710) thoracic duct drainage (Paulus et al., Arthritis Rheum. 1977, 20, 1249-1262) and total node irradiation (Trentham et al., N. Engl. J. Med. 1981, 305, 976-982). All of these modalities have resulted in varying degrees of improvement, but all also have obvious drawbacks.
Patients with rheumatoid arthritis have also been treated with one or more 5 day infusion courses with monoclonal anti-CD5 coupled to Ricin-A chain (Strand et al., Arthritis Rheum. 1993, 36, 620-630). In this open-label trial, improvement rates were 50-68% at one month and 22-25% at 6 months (two clinical trials were included). All patients produced antibodies against the anti-CD5 conjugate and most experienced a transient decrease in CD3/CD5 positive T cells with recovery after 2-4 weeks.
Since cytokines also play important pathophysiologic roles in rheumatoid arthritis, research into therapeutics has also focused in this area. Tumor necrosis factor (TNFA) has received attention because it is consistently found in synovium of patients suffering from rheumatoid arthritis. In addition, anti-human TNF was demonstrated to prevent the development of arthritis in a transgenic human TNFxcex1 mouse model. Using chimeric (mouse-human) antibodies to TNFxcex1, twenty patients with active rheumatoid arthritis were treated (Elliott et al., Arthritis Rheum. 1993, 36, 1681-1690). Patients were given 20 mg/kg in divided doses weekly either over 2 or 4 weeks. They found overall improvement in the Ritchie Articular Index, joint count and C-reactive protein (CRP) levels, and reported no significant toxicity.
Immunization of patients having rheumatoid arthritis with autologous T cell lines established from cells obtained from RA synovial fluid (SF) and/or synovial tissue has also been shown to be of benefit in some patients (Kingsley and Verwilghen, Clin. Exp. Rheumatol. 1993, 11, S63-S64; Lohse et al., J. Autoimmunity 1993, 1, 121-130; vanLaar et al., J. Autoimmunity 1993, 6, 159-167).
Regarding treatment of humans with allogeneic mononuclear cells (MNC), patients receiving living-related renal transplants have been transfused with allogeneic blood in an attempt to limit the immune response. Similar therapies employing MNC have been applied in recurrent pregnancy loss since about 1981 based on the notion that the fetus represents an allogeneic xe2x80x9cgraftxe2x80x9d and that women who have no demonstrable known cause for recurrent spontaneous abortion (RSA) are likely to be immunologically rejecting their fetuses. Since 1985, the inventor has immunized over 1500 women diagnosed as having RSA with MNC from their spouses. World-wide it is estimated that about 25,000 patients have received this treatment. No serious side effects from this treatment have been found.
Remission of rheumatoid arthritis occurs in about 70% of all pregnant women suffering from rheumatoid arthritis. Pregnancy induced remission was originally believed to be due to increased levels of cortisol but, clearly, it is not entirely due to hormonal effects. It has been observed that during pregnancy, women with rheumatoid arthritis who experience remission carry fetuses that are more disparate than similar to themselves with respect to class II alleles of the human leukocyte antigens HLA-DRB1, xe2x88x92DQA and xe2x88x92DQB (Nelson et al., N. Eng. J. Med. 1993, 329, 466-471). The immunologic mechanism(s) underlying this effect is not known; however, hypotheses include induction of suppressor mechanisms or displacement of arthritogenic peptides from maternal antigen presenting cells (APC) by fetal class II peptides thus subverting an arthritis-inducing immune response. Alternatively, maternal T cell recognition of specific allogeneic or fetal HLA-DR peptides may cause a switch from a predominantly proinflammatory response to one that is protective or suppressive.
While rheumatoid arthritis remains the prototype disease that improves during pregnancy, Multiple Sclerosis (MS) an autoimmune disease that affects about 160,000 women of child-bearing age in the U.S. (Davis and Maslow, Obstet. Gynecol. Surv. 1992, 47, 290-296) and that exhibits immunopathogenetic features similar to RA may be modulated by pregnancy. Pregnant patients with MS have been shown in retrospective studies to experience fewer exacerbations than non-pregnant historical controls and to have post-partum disease flares (Davis and Maslow, Obstet. Gynecol. Surv. 1992, 47, 290-296; Abramsky, O., Ann. Neurol. 1994, 36, S38-S41; Hutchinson, M., J. Neurol. Neurosurg. Psychiatry, 1993, 56, 1043-1045). Prospective studies of MS patients have confirmed the retrospective analyses (Bernardi et al., Acta Neurol. Scand. 1991, 84, 403-406; Birk et al., Arch. Neurol. 1990, 47, 738-742; Roullet et al., J. Neurol. Neurosurg. Psychiatry 1993, 56, 1062-1065; Sadovnik et al., Arch. Neurol. 1994, 51, 1120-1124). Furthermore, brain lesions in MS demonstrated by magnetic resonance have been shown to improve during pregnancy and return to the pre-pregnancy state in the postpartum period (van Walderveen et al., Neurology 1994, 44, 327-329). Like RA, MS has been treated with immunosuppressive drugs and more recent trials have included the use of monoclonal antibodies to T cell subsets, T cell receptors, cytokines, and adhesion molecules (Whitaker J. N., Ann. Neurol. 1994, 36, S103-S107; Utz and McFarland, J. Neuropath. Exp. Neurol. 1994, 53, 351-358). Recent studies demonstrate that a synthetic CD4 peptide analog inhibits experimental allergic encephalomyelitis (EAE) in a mouse model (Jameson et al., Nature 1994, 368, 744-746). Immunomodulation using both alpha- and 10 beta-interferon have undergone clinical trials (Durelli et al., Neurology 1994, 44, 406-413; Connelly, J. F., Ann. Pharmacother. 1994, 28, 610-616).
Spondyloarthropathies (HLA-B27 related diseases) are more common in males than in females. However, ankylosing spondylitis (AS), psoriatic arthritis (PS), and Reiter syndrome (RS) can affect women in the child-bearing age. Approximately 20% of patients suffering from the connective tissue disorder ankylosing spondylitis also experience remission of symptoms during pregnancy (Ostensen and Husby, xe2x80x9cSeronegative spondylarthritis and ankylosing spondylitis: Biological effects and managementxe2x80x9d, Pregnancy, Autoimmunity and Connective Tissue Disorders, edited by Scott, J. S. and Bird, H. A., Oxford Univ. Press, Oxford, New York, Tokyo, 1990, p. 163-184). In addition, while a systematic study of pregnancy effects on Psoriatic arthritis (PA) has not been reported, it is of interest that one of the pregnancy induced remission patients initially described by Hench in Mayo Clin. Proc. 1938, 13, 161-167 had PA.
In addition, the organ-specific autoimmune disease, Myasthenia gravis (MG), has been shown to have a variable response during pregnancy with about 30% of patients experiencing remission and 40% experiencing exacerbation (Varner, M. W., Semin. Perinatol. 1991, 15, 238-250; Plauche, W. C., Clin. Obstet. Gynecol. 1983, 26, 592-604).
The known phenomenon of pregnancy-induced remission and post partum exacerbation of rheumatoid arthritis (Persellin, RH, Bull. Rheum. Dis. 1976, 77, 922-927) led to the use of gamma globulin eluted from placentas in the treatment of rheumatoid arthritis. In one study, 11 patients were treated with placenta-eluted gamma globulin and improvement was noted in seven of these patients (Sany et al., Arthritis Rheum. 1982, 25, 17-24). High dose intravenous immunoglobulin (IVGG) has also been shown to be effective in modulating the course of rheumatoid arthritis (Tumiati et al., Arthritis Rheum. 1992, 35, 1126-1133). Ten patients with active, severe rheumatoid arthritis were treated with 6 monthly infusions. All patients showed improvement; however, all patients also relapsed within weeks of the last infusion.
It has now been found that treatment of patients with active rheumatoid arthritis by immunization with allogeneic MNC can result in amelioration of symptoms and improvement in disease activity indices. This treatment approach was taken in order to determine if the beneficial effects of pregnancy on these autoimmune diseases could be duplicated in non-pregnant patients. Treatment with allogeneic MNC can also be used in the treatment of a number of autoimmune disease, including, but not limited to, Multiple Sclerosis, Spondyloarthropathies, and Myasthenia Gravis.
An object of the present invention is to provide a method of treating autoimmune diseases which comprises administering an effective amount of allogeneic mononuclear cells or molecules derived from these cells to an individual suffering from an autoimmune disease.
Another object of the present invention is to provide a composition for the treatment of autoimmune diseases comprising purified allogeneic white blood cells or molecules derived from these cells.
Administration of an effective amount of allogeneic white blood cells or molecules derived from these cells can be used to treat patients suffering from a number of different autoimmune diseases. Examples of autoimmune diseases which can be treated by administration of these cells include, but are not limited to, rheumatoid arthritis, Multiple Sclerosis, Spondyloarthropathies, and Myasthenia Gravis. This treatment can also be used as an adjunct to immunosuppressive drug treatment of organ graft recipients.
By xe2x80x9ceffective amountxe2x80x9d it is meant a concentration of allogeneic mononuclear cells or molecules derived from these cells which, when administered to a patient suffering from an autoimmune disease, produce a beneficial effect. For example, in patients suffering from rheumatoid arthritis, approximately 80 to 100 million cells administered in a standard buffered salt solution (Lactated Ringers solution) at 6-8 week intervals has been found to be an effective amount, alleviating patient suffering.
Allogeneic MNC has been administered to 10 female patients with active rheumatoid arthritis. In each instance, MNC were obtained from the patient""s spouse or an individual chosen by the patient. In this first trial, patients received a series of at least 3 injections of approximately 108 MNC at 6 week intervals. No adverse effects were noted in any of the patients. Clear improvement in at least 2 of the parameters measured occurred in 7 of 10 patients. Table 1 shows results of Arthritis Impact Measurement Scales (AIMS) scores, which provides a numerical means of following disease activity, physician global assessments, patient assessment of pain, swollen joint counts, and erythrocyte sedimentation rate (ESR) and/or C-reactive protein (CRP) determination in a number of patients entered.
In Table 1, ESR (erythrocyte sedimentation rate) is measured in mm/hr. CRP (C-reactive protein) is measured in mg/dl. ND means xe2x80x9cnot measuredxe2x80x9d .
A summary of clinical disease activity assessments on the ten patients who have completed a series of three MNC treatments at 6 week intervals is provided in Table 2. Each separate analysis revealed statistically significant improvement at 95% confidence (paired Student""s test).
It may be that class II major histocompatibility (MHC) gene products are responsible for the beneficial effect in RA observed after MNC treatment, just as it is class II disparity between a mother an fetus that appears to induce pregnancy-associated remission of RA. The genes of the major histocompatibility complex direct the synthesis of proteins that can be found on the surfaces of most cells. These proteins are referred to as the human leukocyte antigens (HLA) or sometimes as xe2x80x9cMHC determinantsxe2x80x9d. HLA are molecules that determine individuality within a species, bind and present antigens to immunocompetent cells, and are targets of graft rejection by immune effector cells. Thus, HLA are both necessary for immune responses to occur in individuals and can be targets of immune responses. HLA can bind an individual""s own proteins and present these to the immune system. In some individuals this may result in autoimmune disease. MHC genes also determine susceptibility to certain diseases, for example, rheumatoid arthritis. HLA are designated class I or class II, based on their structure. Class I HLA are comprised of a single transmembrane alpha chain associated with beta-2 macroglobulin (xcex2-2 m) and usually interact with CD8+ cytotoxic T cells. Class II HLA have both alpha and beta transmembrane heavy chains and interact with CD4+ T cells that mediate helper and inducer effects and delayed-type hypersensitivity which is the classical histopathology of RA. Class I HLA antigens are present on virtually all nucleated cells in the body and are highly expressed on cells of the immune system. Class II HLA antigens are restricted in their distribution and are found predominantly on certain cells of the immune system. Relevant to the present invention, T cells express only class I antigens while B lymphocytes and monocytes express both class I and II antigens. These types of cells can be isolated from each other by depleting one or the other groups of cells thereby providing two sets of cells for comparison in immunization procedures. MNC prepared form whole blood contain T cells, B cells and monocytes. Only T cells remain when MNC is treated with an antibody directed against class II HLA antigens. An example of such an antibody is the monoclonal antibody known as L243. Only B cells and monocytes remain if MNC is treated with a monoclonal antibody that only reacts with T cells. Anti CD3 is one example of such an antibody.
Patients suffering from an autoimmune disease such as rheumatoid arthritis, Multiple Sclerosis, Spondyloarthropathies, Myasthenia Gravis may be treated with whole MNC populations (containing monocytes, B cells and T cells) or a sub-population of MNC. Either the population of B cells plus monocytes (positive for both class I and class II HLA molecules), or the population of T cells (positive for class I but not class II HLA) are believed to mediate the effects. There are several means by which these cells can be effectively separated from each other which are routine to those of skill in the art including, but not limited to, magnetic cell sorting that employs a device and reagents manufactured by Immunicon Corp. (Reg) Huntington Valley, Pa. In one embodiment, MNC are treated with formalin to increase antigenicity of the cells and negate the possibility of these cells causing graft vs. host disease in an immunocompromised individual.
It is also believed that a beneficial effect can result from the treatment of patients suffering from an autoimmune disease with purified class I or class II molecules. Presentation of these molecules on the allogeneic cell surface is not required. Thus, compositions comprising purified class I and/or class II HLA molecules from single, selected or pooled donor white blood cells; portions of class I and/or II molecules (attenuated molecules or peptides) fractionated from whole molecule preparations; and synthetically prepared peptides or larger molecules based on the knowledge of amino acid sequence and structure studies of the class I or II molecules may be administered.
In a preferred embodiment, compositions of the present invention which contain molecules as described above are presented to the patient with the patient""s own mononuclear cells. For example, cells of specifically identified donors or the patient""s own cells which are obtained, treated with the composition and reinjected into the patient, can be used. The composition can be attached to the patient""s own mononuclear cells in a number of ways, including chemical attachment of the relevant product to the patient""s cells, and attachment of the relevant product to the cells. In a preferred embodiment monocytes are used, as these cells have the capability of binding the class I or class II molecules/peptides as one of their normal functions. The procedures required to produce compositions of the present invention are routine to an individual skilled in the arts of immunology and molecular biology/chemistry.
Methods of identifying appropriate patient donor pairs which increase the probability of the alloimmunization treatment being effective in a selected patient have also been developed. These methods are based upon the measurement of specific differences between histocompatibility genes or antigens expressed on the MNC of donors and patients or in vitro immune responses of patient T lymphocytes to donor MNC or MNC membrane extracts or by determining the presence of antibodies directed against MNC membrane extracts either before immunization or following the first treatment.
Susceptibility to the development of RA has been suggested to be related to a sequence of DNA that is found as an allelic variant in the third hypervariable region of HLA DR4 beta chain (DRB1) (Nepom et al., Arth. and Rheumatism 1989, 32:15-21; Weyand et al., Ann. Int. Med. 1992, 117:801-806). These sequences, known as DRB1*0401, *0404 and *0408, have been identified using sequence specific oligonucleotide probes (SSOP) in DNA extracts of leukocytes from RA patients. The allelic variants are believed to either encode an HLA class II peptide that binds an arthritogenic substance or to encode a self class II peptide that stimulates arthritogenic T cell clones. Since the beneficial effect of alloimmunization of RA patients and patients suffering from an autoimmune disease may be based upon specific differences between DRB DNA of donors and patients, DNA based tissue typing using SSOP can provide an indicator as to who will and who will not respond to treatment. For example, if donor and patient shared or had closely related DRB1*0401 sequences than a beneficial effect of immunization would not be expected, whereas if they were significantly different, alloimmunization would be expected to be more effective.
Patients can also be selected for immunotherapy or donor-patient pairs on the basis of a patient""s lymphocyte responses to a panel of donor lymphocytes or to donor MNC membrane extracts. Patient MNC can be cultured with donor MNC or membrane extracts and the cell proliferation can be measured by conventional methods such as [3H]-thymidine incorporation or IL-2 production by responding cells. In addition, culture supernatants from the donor-patient MNC pairs can be tested for the presence of TH2-related cytokines such as IL-4, IL-10 and TGFxcex2. These cytokines are primarily suppressive of delayed-type hypersensitivity reactions which represents the immunopathology round in RA joint tissues. Thus, appropriate donor patient-pairs can be selected by determining which donor stimulates the strongest production of TH2 cytokines by patient lymphocytes.
Patient sera can also be tested for the presence of antibody to pooled MNC extracts. Using an enzyme linked immunosorbent assay (ELISA) and Western blotting, IgG and IgM antibodies against MNC membrane extracts were detected. Pooled MNC from 10 or more donors were used for the preparation of membrane extracts in accordance with the procedure described by Goldberg et al., Am. J. Reprod. Immunol. 1995 33:21-30. The membrane extracts was then used as the target antigen in an ELISA and as the antigen source in a polyacrylamide gel electrophoresis (PAGE) followed by Western blotting using patient sera as a source of antibody. Results of binding in ELISA and of finding antibodies in sera, when correlated to beneficial alloimmunization outcomes can provide another means of patient selection.
The following examples are provided for illustrative purposes only and are not intended to limit the invention in any way.

Composition and method for allogeneic mononuclear cell immunotherapy


The invention is directed to novel cryogenic liquid transport and storage containers, which utilize external coolant tanks to supply cooling to a cryogenic liquid storage tank. The coolant tanks are mounted above the cryogenic liquid storage tank such that the length of the cryogenic liquid storage tank is capable of extending the entire length of the transport container.

a. Field of the Invention
The instant invention is directed toward the use of longitudinally-mounted external coolant tanks (particularly liquid nitrogen tanks) to supply cooling to a cryogenic liquid (particularly liquid helium) transport container.
b. Background Art
Liquid helium is shipped in vacuum-insulated, double-walled intermodal tank containers that consist of one or more outer vacuum vessels, each encapsulating one or more thermally insulated cryogenic liquid inner vessels suspended by a low heat leak support system. A thermal shield cooled by liquid nitrogen is placed in the annular space between the helium-containing inner vessel and the outer vacuum vessel to reduce heat leak to the helium. The entire system, including all piping and appurtenances, must fit within a structural framework of standardized length and width.
Helium is a rare and expensive resource that is found in only a few locations in the world. It is primarily used in the United States, Japan, and Western Europe, often far from the limited supply points. Helium is shipped as an extremely cold liquid with a normal boiling point of xe2x88x92452xc2x0 F. and is exceptionally temperature sensitive. Liquid nitrogen, a less expensive product with a normal boiling point of xe2x88x92320xc2x0 F., is used to thermally shield the colder helium.
Shipping expenses are a significant portion of the delivered cost of liquid helium because of its low density and exotic shipping container. Helium containers presently use an internal liquid nitrogen coolant supply vessel located at the aft end of the container adjacent to the liquid helium vessel; both are surrounded with a single outer vacuum jacket. This location prevents the helium inner vessel from extending the full length of the standardized frame. A longer helium inner vessel would increase the payload per transit improving the transportation economics.
Liquid helium container design has focused on reducing heat leak to the helium to achieve a nonventing hold time of over 30 days. The first liquid helium containers used a transverse mounted external liquid nitrogen tank located in an elevated position across the rear end of the container. This design significantly limits the actual length of the liquid helium inner vessel. Advantages of the design included ample space for external piping and valves, gravity head aiding the liquid nitrogen transfer to the thermal shield, and simpler fabrication of the main tank assembly.
U.S. Pat. No. 3,782,128, issued Jan. 1, 1974, reflects current container design that employs a circumjacent internal liquid nitrogen vessel. The contents of this patent are hereby incorporated by reference as though fully set forth herein. The liquid helium inner vessel uses more, but still not all, of the standardized frame length and adds about 1500 gallons of capacity over the previous design. Disadvantages include a complex tank assembly and support system, limited space for external piping and valves, liquid nitrogen supply distribution dependent upon regulated pressure differential, and the liquid helium inner vessel length is still limited by the liquid nitrogen supply location. No known prior design locates the liquid nitrogen supply in a position that does not restrict the liquid helium inner vessel length.
The present invention maximizes the liquid helium volume that can be transported in the container by employing one or more liquid nitrogen coolant tanks mounted in an elevated longitudinal position running primarily parallel to the helium tank assembly. This arrangement allows the liquid helium inner vessel to extend the entire forty feet of a standard container adding an additional capacity of up to 1000 gallons over current art. The helium tank assembly and support system is simpler. The high elevation of the coolant supply tanks also ensures that the thermal shield stays liquid-filled because of gravity and also reduces the required operating pressure and corresponding saturated liquid temperature, thus further reducing heat leak to the helium.
The inventive aspects include the location, mounting, and interface of the liquid nitrogen supply tank(s). One or more long, narrow vacuum-jacketed external nitrogen tanks are efficiently located in a previously unused portion of the container envelope. The mounting provides structural support of the external nitrogen supply tanks that is isolated from the helium inner vessel support system. The elevation and piping interface provides the maximum possible static pressure head when feeding the liquid nitrogen cooled thermal shield. The liquid nitrogen vessels may also have a cross-sectional shape other than round because of the lowered operating pressure.
The present invention includes a fluid-transporting container comprising the following: a space envelope defined by a plurality of frame corner castings in which the space envelope has a length; a plurality of container end frames are connected to the frame comer castings thereby defining a support system; a cryogenic liquid storage tank adapted to contain a cryogenic liquid which extends the length of the space envelope and suspended by the support system; at least one coolant tank adapted to contain a cooling liquid, which is mounted at least partially above the storage tank and within the space envelope; at least one thermal shield surrounding at least a portion of the cryogenic liquid storage tank; and a fluid supply system operatively connecting the coolant tank(s) and the thermal shield(s).
The present invention further includes a cryogenic fluid-transporting system comprising the following: a cryogenic liquid storage tank adapted to contain liquid helium having a first outer vessel and a first inner vessel, thereby defining an annular vacuum space between said first inner and outer vessels; at least one thermal shield in the annular vacuum space to reduce heat leak from the first outer vessel to the first inner vessel; at least one elongated coolant tank having a second inner vessel adapted to contain a cooling liquid and a second outer vessel surrounding the second inner vessel thereby defining a second annular vacuum space between the second inner and second outer vessels, in which the elongated coolant tank(s) is mounted at least partially above the cryogenic liquid storage tank; and a fluid supply system operatively connecting the elongated coolant tank(s) and the thermal shield(s).
The present invention further includes a system for transporting liquid helium comprising the following: a relatively larger liquid helium tank assembly adapted to contain liquid helium in which the liquid helium tank assembly has a first longitudinal axis; at least one thermal shield extending at least partially around a portion of the liquid helium tank assembly; and at least one relatively smaller liquid nitrogen supply tank assembly adapted to contain liquid nitrogen in which each liquid nitrogen tank assembly has a second longitudinal axis, wherein each relatively smaller liquid nitrogen supply tank assembly is mounted in an elevated position relative to the relatively larger helium tank assembly, and in which each second longitudinal axis is oriented substantially parallel to the first longitudinal axis, and further wherein the liquid nitrogen tank assembly(ies) is in fluid communication with the thermal shield(s) to supply a controlled quantity of liquid nitrogen to the thermal shield(s).
The present invention further includes a cryogenic fluid-transporting system comprising the following: a space envelope defined between a plurality of opposed pairs of container end frames, wherein the space envelope has an upper portion and a lower portion; a first vacuum-insulated, double-walled intermodal tank comprising a first outer vacuum vessel mounted in the lower portion of the space envelope between the opposed pairs of container end frames, and a first inner vessel suspended within the first outer vacuum vessel by low heat leak structural supports, wherein a first annular vacuum space exists between the first inner vessel and the first outer vacuum vessel; a pair of second vacuum-insulated, double-walled intermodal tanks each comprising a second outer vacuum vessel mounted in the upper portion of the space envelope between the opposed pairs of container end frames and at least partly above the first outer vacuum vessel, and a second inner vessel suspended within the second outer vacuum vessel by low heat leak structural supports, wherein a second annular vacuum space exists between the second inner vessel and the second outer vacuum vessel; at least one thermal shield extending at least partially within the first vacuum jacket to reduce heat leak to the first inner vessel; and trace lines extending along and in thermal contact with the thermal shield(s) in which the trace lines are in fluid communication with each of the two second inner vessels.
Other aspects, features, and details of the present invention will be apparent from reading the following description and claims, and from reviewing the accompanying drawings.

Liquid helium transport container with longitudinally-mounted external liquid nitrogen coolant tanks


A catheter is adapted to exchange heat with a body fluid, such as blood, flowing in a body conduit, such as a blood vessel. The catheter includes a shaft with a heat exchange region disposed at its distal end. This region may include hollow fibers which are adapted to receive a remotely cooled heat exchange fluid preferably flowing in a direction counter to that of the body fluid. The hollow fibers enhance the surface area of contact, as well as the mixing of both the heat exchange fluid and the body fluid. The catheter can be positioned to produce hypothermia in a selective area of the body or alternatively positioned to systemically cool the entire body system.

1. Field of the Invention
This invention relates generally to apparatus and methods for producing heat exchange with body tissue, and more specifically to methods and apparatus for the hypothermic treatment of a body fluid in a body conduit.
2. Discussion of the Prior Art
Many of the advantages of hypothermia are well known. By way of example, it has been found particularly desirable to lower the temperature of body tissue in order to reduce the metabolism of the body. In stroke, trauma and several other pathological conditions, hypothermia also reduces the permeability of the blood/brain barrier. It inhibits release of damaging neurotransmitters and also inhibits calcium-mediated effects. Hypothermia inhibits brain edema and lowers intracranial pressure.
In the past, hypothermic treatment has been typically addressed systemically, meaning that the overall temperature of the entire body has been lowered to achieve the advantages noted above. This has been particularly desirable in surgical applications where the reduced metabolism has made it possible to more easily accommodate lengthy operative procedures. An example of this systemic approach includes catheters for transferring heat to or from blood flowing within a patient's vessel, as disclosed by Ginsburg in U.S. Pat. No. 5,486,208. A closed loop heat exchange catheter is also disclosed by Saab in U.S. Pat. No. 5,624,392. A cooling device for whole-body hyperthermia that utilizes the circulatory system of the body is known to be more efficient since the entire volume of the body is constantly perfused with the cold fluid at a capillary level.
Likewise, various other means of cooling the body have been tried with cooling blankets, ice water bladder lavages, ice baths, esophageal catheters and their associated methods. All of these devices require a considerable time to cool the body since the primary heat transfer occurs through the skin or the skull. A more efficient body cooling device that can quickly cool and accurately control the body temperature is required.

This patent is subject to a terminal disclaimer.

Indwelling heat exchange catheter and method of using same

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