 infections.
The course of treatment for toxoplasmosis in pregnant individuals is determined by the stage in pregnancy and whether the infection is acute or chronic. The purpose of early treatment is to attempt to prevent transmission of the parasite to the fetus. However, the fetus may be treated by treating the mother during gestation. If infection is acute, the antibiotic spiramycin may be administered but is of unproven efficacy. More effective drugs such as pyrimethamine and sulfadiazine, especially when used in combination, are often used after the first trimester of pregnancy (pyrimethamine may be teratogenic) when the diagnosis of infection of the fetus has been established by prenatal diagnostic techniques. Otherwise this particular drug combination is generally not used during pregnancy because of the potential toxicity for the mother and for the developing ferns [21].
Treatment of toxoplasmosis in non-pregnant individuals is initiated and maintained with a drug regimen involving a combination of folate antagonists, such as pyrimethamine and sulfadiazine [1, 14]. If the disease is identified soon enough, treatment is reasonably effective in combatting the acute disease. However, due to poor tolerance of the drugs, especially of the sulfa compounds in AIDS patients, maintenance on the drug therapy is frequently not possible, and recrudescence of the infection is often observed (that is, the drug therapy reduces but does not eliminate the parasite infection).
Rifamycin compounds are macrocyclic antibiotics that have been shown to be useful in a number of selective therapeutic applications. For example rifampin has the following structure: ##STR1## However, rifampin was tested for effectiveness in treating toxoplasmosis and was shown to have no protective effect in mice challenged with a lethal inoculum of toxoplasma [18]. Rifampin at concentrations of 50.mu.g/ml and greater significantly inhibited multiplication of toxoplasma in L-cell cultures. However, similar concentrations also inhibited growth of L-cells. Because the toxicity of rifampin for L-cells and its inhibition of Toxoplasma multiplication intracellularly in vitro occurred at the same concentration of the drug, it was reported [18] that rifampin was likely to inhibit Toxoplasma multiplication by its toxic effect on the L-cells. On the other hand, rifamycin compounds are generally considered to be effective against a limited number of pathological organisms, generally Gram-positive bacteria (including mycobacteria, staphylococci, and streptococci) and some Gram-negative bacteria (
infections. 
 The course of treatment for toxoplasmosis in pregnant person is determine by the stage in pregnancy and whether the infection is acute or chronic. The determination of early treatment is to attempt to prevent infection of the leech to the fetus. However, the fetus may be treated by treating the mother during gestation. If infection is acute, the antibiotic spiramycin may be administer but is of unproven efficacy. More effective drugs such as pyrimethamine and sulfadiazine, specially when use in combination, are often use after the first trimester of pregnancy (pyrimethamine may be teratogenic) when the diagnosis of infection of the fetus has been establish by prenatal diagnostic techniques. Otherwise this particular drug combination is broadly not used during pregnancy because of the potential toxicity for the mother and for the developing fern [ 21 ]. 
 Treatment of toxoplasmosis in non - pregnant individual is initiated and maintained with a drug regimen involving a combination of folate antagonist, such as pyrimethamine and sulfadiazine [ 1, 14 ]. If the disease is identified soon enough, treatment is reasonably effective in combatting the acute disease. However, due to poor tolerance of the drugs, especially of the sulfa compounds in AIDS patients, maintenance on the drug therapy is frequently not possible, and recrudescence of the infection is often observed (that is, the drug therapy shrink but does not eliminate the parasite infection). 
 Rifamycin compounds are macrocyclic antibiotic that have been show to be useful in a number of selective curative applications. For case rifampin has the following structure: # # STR1 # # However, rifampin was test for effectiveness in treating toxoplasmosis and was shown to have no protective effect in mice challenge with a lethal inoculum of toxoplasma [ 18 ]. Rifampin at concentrations of 50.mu.g / ml and great importantly inhibit multiplication of toxoplasma in L - cell cultures. However, exchangeable concentrations also inhibited increase of L - cells. Because the toxicity of rifampin for L - cell and its inhibition of Toxoplasma generation intracellularly in vitro occurred at the same concentration of the drug, it was reported [ 18 ] that rifampin was likely to suppress Toxoplasma multiplication by its toxic effect on the L - cells. On the early hand, rifamycin compounds are generally view to be effective against a limited number of pathological organisms, generally Gram - positive bacteria (including mycobacteria, staphylococci, and streptococci) and some Gram - negative bacteria (
 invections.
The course of trtatment for toxoplasmosiv in pdegnant kndividuals is determined by tye stqge in pregnancy and wfether thv infectiin iw acute or rgronic. Bke pudiose mh early treatmekt is to atdempt to prevett txansmission of the parasite to the fqtus. Hoeeger, the fetus iay nq trsated by treating the mother durinf gestauion. If infection os acute, the antibiotic splramjcin may be adminidtered but us os unproven efwicacy. Mort zffective dtugs such as pyrimethamine and sjlfadnazine, espexiqllj when used mn comfination, are often uved aftrr the first tvimesver if pregnancy (pyrimethemine may be teratoggnic) when dhz diagnosis of infectuob of jhe fatus yas betn xstzblishfd uy prenatal diagnostic techniques. Otherwixe nnis particulzr drud sombination is generally not used durinc pdegnancy because of the potential toxicity flr the moeher and for the developing ferns [21].
Treatment of tofoplaaoosnw in vin-oregnant individuals is initiated and maintaigsd wpth a drug regimek involving a combonwtojn of folate xntagoujsfs, such as pyrimetjamine wnd sylfadiazige [1, 14]. If the disease is identifiwd soon enouyh, rreatment is reasouably effectnve in combstting the acute diseasz. Howeber, due to ooor toledxnce of the drugr, expacially of the sulfa compotnds in AMDS pctients, oainjenance on the drkg thcsapy is frequently not kossibne, and recgudescence of the infection is often observed (tvat is, the brug tmerapy reduces fut does not ekiminatz the oarasite ihfectioi).
Rifamycin cjmpounds are kwcrocyclic aitibioticf thqt hqve beev shown to be uxeful in c numver of selective tmerapgufic applicationw. Fir example rifakpiv hws tie fojnowing strucdure: ##STF1## Howexer, rifampik wxs trsted for effectivenass jn treating toxoplssiosis ane was shjwn to have np protective effecu in mmce chellengrd rith a lethal inoculum of toxollasma [18]. Rlfaipin at concqntrqtions of 50.mu.y/ml and greater significantly inhibited nultiplication of roxoplasma in L-cell gultures. Howxver, symilar cotcentrations also inyibited growth of L-cells. Because the tkxicitf of gifampin for L-cells and its inhibition of Toxoplasma multiplication intraxellulerjy in vitro occirred ac tke same conreitration of the dgug, it was reported [18] that rifampmn was likalv to inhibit Toxoplasma multillkcation by itr toxic effect on the L-cslls. On yhe other hand, rifamycin compoumds are generally considcred to bw effsctive agamnst a limited numbet of pctholotical oeganlsms, generally Grsm-iositive bwctecia (including mycobacteria, staphyloxocci, qnf streptococci) aid some Gram-kenative bactetia (
infections. The course of treatment for toxoplasmosis individuals determined by stage in pregnancy acute chronic. The purpose early treatment is attempt to prevent transmission of the to the fetus. However, the fetus may be treated by treating the mother gestation. If infection is acute, the antibiotic spiramycin may be administered but is unproven More drugs as pyrimethamine and sulfadiazine, especially when used in combination, are often used after the first trimester pregnancy (pyrimethamine may be teratogenic) when the diagnosis infection of the fetus been established by prenatal diagnostic Otherwise particular drug is not during pregnancy because the potential toxicity for the mother and for the developing ferns [21]. Treatment of toxoplasmosis in non-pregnant is initiated with a regimen a of folate antagonists, pyrimethamine and sulfadiazine [1, 14]. If identified soon enough, treatment is reasonably effective in the acute However, due to poor tolerance of drugs, especially of the sulfa compounds in AIDS maintenance on the drug therapy is frequently not possible, and recrudescence of the infection is (that is, the drug reduces but does eliminate parasite Rifamycin are macrocyclic that have been shown to be useful in a number of therapeutic applications. For example rifampin has the following structure: ##STR1## was for effectiveness in toxoplasmosis and was shown have protective effect in mice a inoculum Rifampin concentrations 50.mu.g/ml and greater significantly multiplication of toxoplasma in L-cell However, similar concentrations also the toxicity of rifampin for L-cells and its of Toxoplasma multiplication intracellularly in vitro occurred the same concentration of the drug, it was reported [18] that rifampin likely to multiplication by its toxic effect on the L-cells. the other hand, rifamycin are generally considered to be effective against a limited of organisms, generally bacteria (including mycobacteria, and streptococci) and Gram-negative bacteria (
 infections.
The course of treaTment for toXoplaSmoSis In PregNant Individuals is dETermIned by the stage in pregnaNcy anD wHEtheR ThE infeCtion is ACuTE Or cHrOnIc. THe PUrPose oF eaRly treaTment is to aTteMpT to prevent trANsMission of tHe pArasite to the FetUs. HoweVeR, thE Fetus May Be treAted by TReatinG the motheR dURing geSTation. IF INfEctiOn is acute, the antibIOtIC spiramycin may Be admiNiSTeRED buT is Of unproven EfFicacY. more effECtIVE DruGS such as pyrimeThamine and sULfaDiazinE, eSpeCIally wHen usEd IN coMbination, arE oftEn used aftEr the fIRst trimESter of pRegnanCy (pYriMethAMiNe May Be TEraTOgEniC) WheN the diagNoSiS of inFectION OF the FetUs haS been Established by PreNataL DiaGnostIc tecHniqUeS. OtheRwise tHis paRtIcular drug combiNatiOn is generAllY nOt uSeD duriNG pregnAncY beCause of The poteNTiaL tOXICiTy for the mother and fOr THE dEvelopinG ferns [21].
tReAtMEnt of toxOpLasMosiS IN non-pRegnANt IndividuAls is iNItIaTed and mAiNtaineD wIth A drUg regIMen iNvolviNg a combiNatioN Of folate antagoNIsts, such as pyrIMeTHAmINe anD suLfadiazine [1, 14]. IF the DIseaSe is IDeNtiFIed soOn enoUgH, TrEAtment is reasonably eFfEctive In comBatting the acuTe disease. HOWEVer, due to Poor TOlERance of the drugS, espeCially of thE Sulfa comPoundS in AIDS pAtients, maINTenance oN thE drUg tHerAPY iS frequently noT POssiBlE, and recRudEscence Of tHe iNfeCtiOn Is often obServed (thAt Is, ThE dRug TheraPY reduces BuT doEs Not ElimiNAte the ParasIte iNfEcTIon).
rifamycIN cOMPounDs ArE macRocYcLic anTibiOTicS that haVe been shoWn tO Be usEfUl In a numbEr of selective ThErapeutic aPpLicAtions. fOR example Rifampin has the following STructurE: ##STr1## HoweVer, rIfampin waS teSted foR efFEctiveNess in TreatInG toXOPlasmOSIs And WaS shown to haVE No pRotecTiVe efFect in mIce challenged with a LEthAl inoculum of tOxoPlasMA [18]. riFamPIn AT coNcENtrATIons of 50.mu.g/ml and gReater signIfICaNtly inhibiTEd mUlTiplicaTion of tOxoplASma in L-cEll culturEs. However, SiMilaR COncEntrations Also inhiBited growTH of L-cELlS. BecaUse The toxIcIty Of rifAmpin fOR L-cElls aNd its iNhIbitioN of ToXoPlasma muLtiplication intracellulArly in Vitro OccUrred at thE saME coNcentratiOn of The drug, it wAs rEpoRted [18] tHat RIfampIn waS LiKelY To inhIbit tOxoplasma MUlTipLICaTion by its toXIC EffEct on The l-Cells. ON the Other hand, rifamyciN Compounds are geNeraLLY coNsiDEred To Be effective agaInsT a LIMited numBeR of pathologIcal orgaNiSMs, genErally gram-poSitive bACTeRIa (inclUdinG myCobacteriA, stApHYlococcI, aNd STreptoCoccI) aNd some gram-neGAtivE BActeria (
 infections.
The course of  treatment  fortox opl as mosi s in  pregnant indi v idua ls is determined by th e sta ge in p r eg nancy  and wh e th e r  th ein fec ti o nis ac ute  or chr onic. Thepur po se of earlyt re atment istoattempt to p rev ent tr an smi s sionofthe p arasit e  to th e fetus.Ho w ever,t he fetu s ma y be  treated by treat i ng the mother dur ing ge st a ti o n . I f i nfection i sacute ,  the an t ib i o t ics piramycin may  be adminis t ere d butis  of unprov en ef fi c acy . More effe ctiv e drugs s uch as pyrimet h amine a nd sul fad iaz ine, es pe cia ll y  wh e nuse d  in  combina ti on , are  oft e n u sedaft er t he fi rst trimester  of  pre g nan cy (p yrime tham in e may  be te ratog en ic) when the di agno sis of in fec ti onof  thef etus h asbee n estab lishedb y p re n a t al  diagnostic techni qu e s .Otherwis e this pa rt i cular dr ug  co mbin a t ion i s ge n er ally not  usedd ur in g pregn an cy bec au seofthe p o tent ial to xicity f or th e  mother and fo r  the developi n gf e rn s  [21 ].Treatment o f to x opla smos i sinn on-pr egnan ti nd i viduals is initiate dand ma intai ned with a dr ug regimen i n volvinga co m bi n ation of folat e ant agonists,s uch as p yrime thamineand sulfa d i azine [1 , 1 4].  If  th e di sease is iden t i fied  s oon eno ugh , treat men t i s r eas on ably effe ctive in  c om ba tt ing  thea cute dis ea se.  H owe ver,d ue topoortole ra nc e  of  the dr u gs , espe ci al ly o f t he  sulf a co m pou nds inAIDS pati ent s , ma in te nance o n the drug th er apy is fre qu ent ly not p ossible,  and recrudescence of t h e infec tio n isofte n observe d ( that i s,t he dru g ther apy r ed uce s but d o e snot  e liminate t h e  pa rasit einfe ction). 
Rifamycin compoun d s a re macrocycli c a ntib i o ti cst ha t  ha ve bee n shown to be use ful in a n um b er  of select i veth erapeut ic appl icati o ns. For  examplerifampinha s th e fol lowing str ucture:##STR1##H oweve r ,rifam pin  was t es ted  foreffect i ven ess i n trea ti ng tox oplas mo sis andwas shown to have no pr otecti ve ef fec t in mice  ch a lle nged with  a l ethal inoc ulu m o f tox opl a sma [ 18]. Ri fam p in at  con c entration s  o f 5 0 . mu .g/ml and g r e a ter  sign ifi c antlyinhi bited multiplicat i on of toxoplas ma i n L-c ell cult ur es. However, s imi la r concentr at ions also i nhibited  g r owthof L-c ells.Because t he toxici ty o f r ifampin f orL- c ells an dit s  inhib itio nof Tox oplasm a  mul t i plication intrac ellul a r ly in vit ro oc cu rred at thesame conce ntration of  the d rug,  it w as repo rt ed [18 ] t ha t rifampin was likel y toinhibit  T oxop las ma mul tipl i c ation  byit s t oxic effe c t  o n  t he L-c ells . Onth e ot her hand, rifamyci n c o mpounds  a reg e nerall y  c o n sidered to  be  effe c t ive agains t  a l i mi t ed nu mber o f path ologica l  or ga nisms,gen e r ally Gram -positive bac te ria(includi ng  myc ob act er ia, staphylococ ci, andstreptoc o c ci) an d s o me G r am-neg at ive bacteria  (
 infections.
The_course of_treatment for toxoplasmosis in_pregnant individuals_is_determined by_the_stage in pregnancy_and whether the_infection is acute or_chronic. The purpose_of_early treatment is to attempt to prevent transmission of the parasite to the fetus._However,_the fetus_may_be_treated by treating the mother_during gestation. If infection is_acute, the_antibiotic spiramycin may be administered but is of_unproven_efficacy. More effective_drugs such as pyrimethamine and sulfadiazine, especially when used_in combination, are often used after_the first trimester_of_pregnancy_(pyrimethamine may be teratogenic)_when the diagnosis of infection of_the fetus has been established by_prenatal diagnostic techniques. Otherwise this particular drug_combination is generally not used during_pregnancy because of the potential_toxicity for_the mother and for the_developing ferns [21].
Treatment_of toxoplasmosis_in non-pregnant individuals_is initiated and maintained with a_drug regimen involving_a combination of folate antagonists, such_as_pyrimethamine and sulfadiazine_[1,_14]._If the_disease is identified_soon_enough, treatment_is_reasonably effective in combatting the acute_disease._However, due to poor tolerance of the_drugs, especially of the_sulfa_compounds in AIDS patients,_maintenance on the drug therapy_is frequently not possible, and recrudescence_of the_infection is_often observed (that is, the drug therapy reduces but does not_eliminate the parasite infection).
Rifamycin compounds are_macrocyclic antibiotics that have_been shown_to_be useful in_a_number of_selective therapeutic applications. For example rifampin has_the following_structure: ##STR1## However, rifampin was tested_for effectiveness in treating_toxoplasmosis_and was shown to have no_protective effect in mice challenged with_a lethal inoculum of toxoplasma_[18]._Rifampin_at concentrations of 50.mu.g/ml and_greater significantly inhibited multiplication of toxoplasma_in L-cell cultures._However, similar concentrations also inhibited growth of_L-cells._Because the toxicity of rifampin for_L-cells_and its inhibition of Toxoplasma multiplication_intracellularly_in_vitro occurred at the same_concentration of the drug, it was_reported [18] that rifampin was likely to inhibit Toxoplasma_multiplication by its_toxic effect on the L-cells._On_the_other hand, rifamycin compounds are generally considered to be effective_against a_limited number of_pathological organisms, generally Gram-positive bacteria (including mycobacteria, staphylococci, and streptococci)_and some Gram-negative bacteria (