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In this study, 241 serum samples from individuals exposed to brucellosis were subjected to the Rose Bengal plate test (RBPT); the titre was estimated by standard tube agglutination test (STAT), with positive > or = 80 IU/ml. Randomly selected sera (n = 81) were analysed by complement fixation test (CFT): titre > or = 1:4 was considered positive. Of 241 sera subjected to RBPT and STAT, 177 were negative in both tests; 5 samples tested negative by RBPT but positive by STAT. None was positive by RBPT and negative by STAT. Of 81 sera subjected to CFT, 23 (28.4%) were positive. Both RBPT and CFT found 18 samples positive; 5 samples were positive by CFT and negative by RBPT. Comparison of STAT with CFT showed 13 samples positive by STAT but negative by CFT, and 4 positive by CFT but negative by STAT. The sensitivity and specificity of STAT were 82.6% and 77.6%, respectively, with CFT as gold standard. No test is perfect, and the clinical history coupled with a combination of two or more tests will reduce diagnostic errors.

The synthesis of polyaniline (PANI) containing different carbon nanotubes (CNTs) by in situ polymerization is reported in this study. The samples were characterized by X-ray diffraction and scanning electron microscopy. Fourier transform infrared and ultraviolet–visible spectroscopy were used to determine the change in structure of the polymer/CNT composites. Thermogravimetric analysis showed that the composites had better thermal stability than the pure PANI. Photoluminescence spectra showed a blueshift in the PANI–single-walled nanotube (SWNT) composite. Low-temperature (77–300 K) electrical transport properties were measured in the absence and presence of a magnetic field up to 1 T. Direct-current conductivity exhibited a nonohmic, three-dimensional variable range hopping mechanism. The room-temperature magnetoconductivity of all of the investigated samples except the PANI–SWNT composite were negative; however, it was positive for the PANI–SWNT composite, and its magnitude decreased with increasing temperature. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Polyaniline/multiwalled carbon nanotube (PANI/MWNT) composites were prepared by in situ polymerization. Scanning electron microscope, X-ray diffraction, Fourier transform infrared, Uv-Visible spectroscopy, Fluorescence spectrophotometry were done to characterize the PANI/MWNT composites. Thermal stability was measured by thermogravimetry analysis. The thermal stability of PANI/MWNT composites becomes higher than PANI. Electrical transport properties of different PANI/MWNT composites were investigated in the temperature range 77 ≤ T ≤ 300 K with and without magnetic field up to 1 T. The dc resistivity of PANI/MWNT composites shows different behavior compared to the sample without MWNT. The room temperature dc magnetoconductivity of the samples is negative; however, its sign changes to positive by lowering the temperature, which has been explained by hopping type charge transport. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1767–1775, 2010

Polyaniline (PANI) was synthesized by the well-known oxidative polymerization of aniline with ammonium peroxodisulfate as the oxidant. The morphological, structural, thermal, optical, magnetic, and electrical properties were characterized with scanning electron microscopy, X-ray diffraction, Fourier transform infrared, thermogravimetric analysis, differential scanning calorimetry, ultraviolet–visible spectroscopy, room-temperature magnetic measurements, and low-temperature electrical transport measurements by the standard four-probe method. Greater thermal stability and crystallinity were observed in doped PANI versus pure PANI. Magnetic measurements showed that the magnetic susceptibility was field-dependent. Positive and negative susceptibility values were observed. This may have been due to the interactions of magnetic ions among interchains or intrachains of the polymer matrix. The alternating-current (ac) conductivity was measured in the temperature range of 77–300 K in the frequency range of 20 Hz to 1 MHz. The frequency-dependent real part of the complex ac conductivity was found to follow the universal dielectric response: σ′(f) ∝ fs [where σ′(f) is the frequency-dependent total conductivity, f is the frequency, and s is the frequency exponent] The trend in the variation of the frequency exponent with temperature corroborated the fact that correlated barrier hopping was the dominant charge-transport mechanism for PANI–CoCl2. An anomalous dependence on temperature of the frequency exponent was observed for PANI–CuCl2. This anomalous behavior could not be explained in terms of existing theories. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Powder precursors lithium aluminosilicate (LAS) of low expansion characteristics were synthesized by following the wet interaction technique in the hydroxyhydrogel form using lithium carbonate (Li2CO3), hydrated aluminium nitrate [Al(NO3)3·9H2O], fume silica (SiO2) and zirconium oxychloride (ZrOCl2·8H2O). Dilatometry, X-ray diffraction (XRD), IR analysis, Scanning Electron Microscopy (SEM) and Image analysis were done to study sintering, characteristics phase transformation and microstructure on the sintered specimens. ZrO2 was found to promote the formation of β-eucryptite, and grain size of the sintered specimens could be related to the amount of ZrO2 present in the starting powder precursor. The thermal expansion characteristics were also found to be strongly influenced by ZrO2 content in the specimens.

A powder precursor in the form of hydroxyhydrogel was prepared for the reaction sintering in the h-BN–mullite composite system. The powder precursor contains all the essential elements for the formation of the composite. Characterization of the powder precursor indicated the presence of Al 3+ in predominantly hexacoordinated state. The powder precursor yielded consolidated BN–mullite composite formed during heat treatment of pressed compact in ambient gas atmosphere.

Aluminium hydroxide as a powder precursor for making advanced ceramic materials such as yttrium aluminium garnet (YAG) was prepared from aluminium nitrate and ammonium hydroxide by two different procedures and was analyzed for determining its physico-chemical characteristics. It was observed that through the end products were essentially Al(OH)3, they differ in their physico-chemical properties. Rate constants evaluated by thermal analysis were compared and the differences observed were explained in terms of structural parameters by FTIR and related analysis.

The present work deals with the sintering of SiC with a low melting additive by microwave technique. The mechanical characteristics of the products were compared with that of conventionally sintered products. The failure stress of the microwave sintered products, in biaxial flexure, was superior to that of the products made by conventional sintering route in ambient condition. In firing of products by conventionally sintered process, SiC grain gets oxidized producing SiO2 (∼ 32 wt%) and deteriorates the quality of the product substantially. Partially sintered silicon carbide by such a method is a useful material for a varieties of applications ranging from kiln furniture to membrane material.

Oxidation of SiC is a major constraint during development of metal oxide–silicon carbide composites when processed in oxygen containing environment such as in air. In the present investigation, Mg+2, Al+3 and Zr+4 hydrogels were used as a source of respective oxide and oxidation of SiC in each system was studied. A three-stage mechanism was found to be operative in Al+3 and Zr+4 systems where oxidation at the initial stages was found to be controlled by the nature of the polynuclear complexes formed on the surfaces of SiC particles. At the intermediate stage a transition from polynuclear complex to metal silicate protective layer formation changes the oxidation characteristics. Finally the metal silicates provided the ultimate protection. Mg+2 was found to be ineffective. The extent of retention of SiC in the final composites could be premonitored by controlling the amount and the nature of complexing cations.

Yttrium hydroxide and aluminium hydroxide hydrogel were derived from yttrium nitrate and aluminium nitrate through hydroxy hydrogel route in which SiC particles were kept dispersed. The gel-like mass was heat treated at 900°C in ambient atmosphere followed by heat treatment at 1400°C in Ar atmosphere. The specimens were then sintered in the temperature range of 1800–1950°C in Ar atmosphere with 30 min soaking. The phases were identified by XRD analysis. Microstructure of the sintered materials were analysed by scanning electron micrograph. With this new method of preparation of powder precursors, the process of sintering was easier and almost theoretical density was achieved with moderate hardness. The mechanism of densification was postulated to be a solid-state initiated liquid phase sintering and the overall process of which was activated by the reactive species formed from hydroxy hydrogel powder precursors.

Experimental infection of golden hamsters with the hookworm, Ancylostoma ceylanicum, caused a profound decline in the hepatic microsomal cytochrome P450 content. Concomitant decrease was also noticed in aminopyrine N-demethylase and benzo[a]pyrene hydroxylase activities. However, aniline hydroxylase activity was only marginally elevated during the infection. Microsomal markers, viz., cytochrome b5, NADH-cytochrome-c reductase, and glucose-6-phosphatase, were not significantly altered. Hepatic tissue exhibited an accumulation of lipids, especially phospholipids, triglycerides, and cholesterol, resulting in fatty necrosis around the central vein region. Isolated hepatic microsomes showed a decrease in phosphatidylcholine content. Impairment in hepatic mixed function oxidase (MFO) activities was further confirmed by prolongation in hexobarbital sleeping time and zoxazolamine-induced paralysis. The hepatic MFO system of A. ceylanicum-infected hamsters responded qualitatively and quantitatively in a manner similar to that of control hamsters, upon stimulation with selective chemical inducers like phenobarbitone and 3-methylcholanthrene. Kinetic and in vitro substrate binding studies revealed that for aminopyrine the substrate affinity and the maximum enzyme activity (Vmax) were decreased, while for aniline the binding affinity was decreased and the binding capacity was enhanced. Results indicate specific/selective impairment of the hepatic microsomal cytochrome P450 system during hookworm infection and may have many practical implications in toxicology and pharmacology.

Nanocomposites of polyaniline with some rare earth chlorides like neodymium chloride, europium chloride, and dysprosium chloride were synthesized by chemical oxidative polymerization of aniline. Morphological, structural, thermal, optical, magnetic, and electrical properties of the samples were characterized by scanning electron microscope, x-ray diffractometer, Fourier transform infrared spectrometer, thermogravimetric analyzer, differentiating scanning calorimeter, optical absorption spectroscopy, room temperature magnetic susceptibility measurement, and low temperature electrical transport measurement. Nanocomposites were thermally more stable than pure polyaniline and they were more crystalline than pure polyaniline. Magnetic susceptibilities of the samples were field dependent. Three-dimensional variable range hopping charge transport mechanism was followed by the samples. The dc magnetoconductivity of the composites can be explained in terms of forward interference effect and wave function shrinkage...

Polyamine levels of some helminth parasites were analyzed by reverse phase HPLC of benzoyl derivatives. Setaria cervi, Acanthocheilonema viteae, Hymenolepis nana, H. diminuta, and Ascaridia galli contained higher levels of spermine than spermidine while in Ancylostoma ceylanicum and Nippostrongylus brasiliensis the spermidine levels were higher than spermine; putrescine was either absent or present in minor quantities. The enzymes of polyamine biosynthesis viz., ornithine decarboxylase, S -adenosyl methionine (SAM)-decarboxylase, and arginine decarboxylase were present in very low to negligible amounts in all the parasites examined. A. ceylanicum exhibited high activity of ornithine amino transferase (OAT) and catalyzed appreciable decarboxylation of ornithine. The ornithine decarboxylating activity of A. ceylanicum was localized in the participate fraction containing mitochondria, not inhibited by α-difluoromethyl ornithine, the specific inhibitor of ornithine decarboxylase (ODC), but inhibited in the presence of glutamate, suggesting the involvement of mitochondrial OAT rather than a true ODC in ornithine decarboxylation in this parasite. Significant activity of polyamine oxidase was also detected in helminth parasites. The absence of polyamine biosynthesizing enzymes in helminth parasites suggests their dependence on hosts for uptake and interconversion of polyamines, providing a potential target for chemotherapy.

The microfilariae and adults of Setaria cervi, a filarial parasite of Indian water-buffalo (Bubalus bubalis Linn.) and of other ruminants were analysed for various biochemical constituents. Both stages of the parasite were rich in protein, carbohydrate, and lipids while nucleic acids were detectable in only small amounts. Microfilariae and adults contained 10 and 25% dry matter, 57.4 and 63.0% protein, 8.9 and 14.8% carbohydrate, and 12.8 and 9.2% lipid, respectively. Reducing sugars accounted for 52 and 67% respectively of the total carbohydrate in these two stages. Glycogen accounted for 95% of total carbohydrate in the cold PCA soluble fraction of adult worms while its concentration in microfilariae was very low. Glucose was the main constituent of reducing sugars while concentrations of fructose were very low. Microfilariae contained more lipids, nucleic acids, mucopolysaccharides, and total phosphorus than adults. The phospholipid percentage was higher in microfilariae than in adults. The amino acid pattern of both stages was very similar.

Litomosoides carinii, the filarial parasite of cotton rat (Sigmodon hispidus), utilized labelled glucose and mannose for procuring energy while fructose and galactose were not helpful in this purpose. Studies on the fate of labelled glucose and mannose showed that these sugars led to the synthesis of glycogen.

Setaria cervi, the filarial parasite inhabiting the Indian water buffalo (Bubalus bubalis Linn.) contained almost all the enzymes involved in glycogen degradation. Significant activities of glycogen phosphorylase, glucokinase, phosphoglucomutase, phosphoglucose isomerase, phosphofructokinase, FDP-aldolase, glyceraldehyde-3-phosphate dehydrogenase, phosphopyruvate hydratase, pyruvate kinase, lactate dehydrogenase, glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were detected in cell-free extracts of whole worms. The presence of PEP-carboxykinase, malate dehydrogenase, fumarase and fumarate reductase revealed the functioning of the PEP-succinate pathway in addition to phosphorylating glycolysis and pentose phosphate pathway in the parasite. Excepting fumarate reductase all other enzymes were localized in the particulate-free cytosol fraction, although small amounts of glycogen phosphorylase, aldolase and lactate dehydrogenase were also detected in the mitochondrial fraction.

Monoamine oxidase (MAO), catalysing oxidative deamination of biogenic monoamines, has been detected in adultAscaridia galli. MAO was present in mitochondria and deaminated noradrenaline at the maximal rate, although serotonin, adrenaline, tyramine and dopamine were also degraded but more slowly. Of the organs studied, the body wall, female reproductive organ and intestine, the body wall (containing neuronal structures) showed highest MAO activity. Km value for chick ascarid mitochondrial MAO using tyramine as substrate was 1·66 x 10−3M and it was most active at 2·5 mm tyramine concentration, pH 7·5 and 40°C. MAO ofA. galliappeared to be thermolabile as nearly 80% of its activity was lost when the incubation temperature was increased 5° above optimum.

Polyamine metabolism in Ancylostoma ceylanicum and Nippostrongylus brasiliensis. International Journal for Parasitology 19: 191–198. Spermidine was detected as the major polyamine of Ancylostoma ceylanicum as well as Nippostrongylus brasiliensis . Spermine was present in lower amounts whereas the level of putrescine was even less. S -Adenosylmethionine decarboxylase, a rate-limiting enzyme in the biosynthetic pathway of polyamines, was demonstrated at low levels in both parasites. Decarboxylation of lysine and arginine was absent or negligible and that of ornithine questionable, as the enzyme activity was not inhibited by α-difluoromethylornithine while RMI 71 645, an irreversible inhibitor of ornithine aminotransferase, strongly inhibited the liberation of CO 2 from ornithine. High activity of ornithine aminotransferase was observed in both the parasites and may interfere with the assay for ornithine decarboxylase. Adults of A. ceylanicum were found to rapidly take up spermidine and spermine from incubation medium while uptake of putrescine was very low. These results indicate that hookworms depend on uptake and interconversion rather than de novo synthesis for their polyamine requirement.

Ancylostoma ceylanicum infection in golden hamsters (Mesocricetus auratus) caused marked biochemical and histopathological derangements. Jejunum, the primary site of infection, showed pronounced alterations compared with liver. Though the biochemical composition of jejunum was not significantly altered, activities of a few lysosomal enzymes were enhanced during hookworm infection. Marked damage to mitochondrial and microsomal membranes was reflected in changes in the activities of the marker enzymes from jejunal tissue. Lipid content, especially phospholipids and neutral lipids of hepatic tissue, exhibited marked elevation. Levels of hexokinase, phosphofructokinase, and lactate dehydrogenase were enhanced in jejunal as well as hepatic tissues, indicating activation of the glycolytic machinery during hookworm infection. A decrease in the levels of mucosal disaccharidases indicated damage to intestinal brush border membranes. However, alkaline phosphatase activity was increased in intestinal mucosa during the infection. Light microscopic examination of jejunal tissue revealed peeling off of the upper epithelial layer, activation of the goblet cells, and thickening of muscularis mucosa. However, hepatic tissue did not show gross alterations, except for slight necrosis in the centrilobular region.

(1) Extracts of Ascaridia galli , a nematode parasite of domestic fowl ( Gallus gallus ), contained potent inhibitors of trypsin and chymotrypsin. (2) These inhibitors extracted by TCA and heat treatment and partially purified by DEAE- and CM-cellulose chromatography were found to be proteins of low molecular weight. (3) These inhibitors were nondialyzable, stable up to 15 min at 100 C, and active over a wide pH range (3–10). 8.0 M urea and 0.1 M β-mercaptoethanol had no effect on the inhibitors. (4) Complex formation between the inhibitors and trypsin and chymotrypsin was complete within 60 and 30 sec of contact, respectively.

The presence of biogenic amines has been shown in microfilariae and adults of Litomosoides carinii , the filarial parasite of the cotton rat, Sigmodon hispidus . The amine mosaic of microfilariae differed from that of the adults in that, while no dopamine could be detected in the former, the latter contained all the four amines studied in the present investigations. Also, the amine content of the microfilariae was markedly higher than that of the adult worms.

Tekwani B. L., Tripathi L. M., Mukerjee S., Visen P. K. S., Katiyar J. C., Shukla O. P. and Ghatak S. 1988. Status of the microsomal mixed function oxidase system in the intestine, lungs and kidneys of hamsters during infection with Ancylostoma ceylanicum . International Journal for Parasitology 18 : 11–14. Infection of golden hamsters with Ancylostoma ceylanicum causes significant alterations in microsomal cytochrome P-450 and associated components in intestine, lungs and kidneys. In intestinal microsomes, cytochrome P-450, cytochrome b 5 , heme, cytochrome b 5 reductase, NADPH-cytochrome c reductase and benzo(a)pyrene hydroxylase decreased considerably. This generalized damage in jejunal microsomes appears to be due to marked pathological lesions in this tissue. Lung microsomes exhibited a decrease in cytochrome P-450, heme and benzo(a)pyrene hydroxylase, while cytochrome b 5 , and cytochrome b 5 reductase were not significantly affected. Renal microsomes showed elevation in cytochrome P-450 and benzo(a)pyrene hydroxylase, while other associated components remained unaffected.

SUMMARYGlycogen reserves of whole worms and their body wall, intestines, ovarian and testicular tubules of the avian intestinal nematode,Ascaridia galli, were assayed and on dry-weight basis found to be 14–20 %, except in the testicular tissue which contained only 7 % glycogen.Segments of whole male worms or testicular tubules were found to produce more lactic acid than segments of whole female worms or ovarian tubules. The body wall and intestine of the worms had also appreciable glycolytic activity. Whereas in the segments of whole worms, male and female alike, glycolysis was more active under anaerobic conditions, no differences in glycolytic rates were seen between aerobiosis and anaerobiosis when isolated tissues were used. Exogenously added glucose did not stimulate glycolysis either aerobically or anaerobically to any extent greater than observed in the absence of glucose.Homogenates of whole worms or their different anatomical parts were assayed for enzymic activities associated with the Embden-Meyerhof pathway of glucose assimilation. The crude extracts prior to differential centrifugation, were found to contain glycogen phosphorylase, aldokinases, pyruvate kinase, phosphatases acting on glucose 6-phosphate and hexose diphosphate and 6-phospho-gluconate dehydrogenase. The 105000gparticulate-free supernate was found to have significant activities of the following enzymes: fructokinase, phosphoglucomutase, phosphoglucoseisomerase, phosphofructokinase, aldolase, glyceraldehyde 3-phosphate dehydrogenase, lactic dehydrogenase and glucose-6-phosphate dehydrogenase. This fraction was devoid of NADH or NADPH oxidase activities in the absence of added substrates.Although there was some indication of a negative correlation between low glycogen reserves and high glycolytic activity in the testicular tubules, in general, there was no relationship between glycogen reserve and glycolytic activity on the one hand or between the rate of glycolysis and the specific activities of some of the key glycolytic enzymes in either whole worm or in tissues other than the testicular tubules.The 105000gsupernate was fractionated with ammonium sulphate. The fraction precipitating between 25 and 80 % saturation of the salt was recovered, dialysed and chromatographed on DEAE cellulose column. By a step-wise elution schedule using increasing molarity of NaCl in tris-HCl buffer, pH 7·4, three main protein fractions were obtained representing respectively enolase, aldolase and glucose-6-phosphate dehydrogenase.The recovery of enzyme activity after chromatography on DEAE cellulose was higher than the amount applied to the column suggesting that during the fractionation some naturally occurring inhibitors were removed. About 10- to 20-fold purification of the enzymes was achieved by anion-exchange chromatography.Some properties of the purified enzymes were studied with respect to the affects of enzyme and substrate concentrations, temperature of preincubation and action of divalent cations, some anions, metal chelating agents and SH reagents. The Kmvalues of enolase, aldolase and glucose-6-phosphate dehydrogenase ofA. galliwere 5·9 × 10−4M, 4·5 × 10−3M and 2·4 × 10−3M respectively. Glucose-6-phosphate dehydrogenase was found to be very sensitive to both heat and cold losing activity rapidly even at 43 °C or by freezing and thawing.The SH groups of aldolase were readily blocked bypCMB and presumably byo–phenanthroline. No requirement of any divalent cations was shown by this enzyme which was, however, inhibited by borate ions.Enolase ofA. gallishowed a requirement of Mg2+for full activation. Phosphate, fluoride, EDTA,o–phenanthroline, αα-bipyridyl inhibited the enzyme. Veronal was found to inactivate the enzyme.Glucose-6-phosphate dehydrogenase ofA. galliwas also found to be sensitive to SH reagents and metal chelating agents. The enzyme was activated by Co2+, Mn2+and Mg2+.The evidence presented indicates that segments of whole worms ofA. gallior its anatomical parts are equipped with the enzymatic machinery required to mediate anaerobic breakdown of glucose and to derive energy by this mechanism.The authors are grateful to Dr R. K. Kaushik for help in identifying the worms, to Mr P. A. George for help in the statistical analysis of the data and to Messrs A. C. Kol and S. K. Bose for skilful technical assistance.

Chandlerella hawkingi, the filarial parasite of the Indian jungle crow (Corvus macrorhynchos Wagler) has been shown to utilize glucose to form mainly lactic acid. Eighty five to one hundred percent of glucose is aerobically converted into lactic acid and only 0.5% to pyruvic acid. The parasite possesses significant amounts of aldolase, triose phosphate dehydrogenase, enolase and lactate dehydrogenase activities. However, glucose-6-phosphate, 6-phosphogluconate and isocitrate dehydrogenases could not be detected in measurable amounts. From these results it is inferred that the parasite meets its energy requirement through the process of glycolysis.

Spermine and spermidine were found to be the principal polyamines in the bovine filarial parasite Setaria cervi, whereas putrescine was observed in very low amounts. Studies conducted on the enzymes of polyamine biosynthesis revealed low activity for S-adenosyl-methionine decarboxylase, questionable and negligible activities for the decarboxylation of ornithine and arginine, and appreciable activity for ornithine aminotransferase. Uptake studies with radiolabeled putrescine, spermidine and spermine showed that these amines are rapidly taken up from the medium by an active uptake process. The uptake was temperature-sensitive and abolished at 0-4 degrees C. The questionable presence of biosynthetic enzymes such as ornithine and arginine decarboxylase and, on the other hand, an effective uptake mechanism indicate that the parasite may depend on the host for its polyamine requirement, thereby indicating a possible target for chemotherapy.

Litomosoides carinii infection causes a decrease in liver glycogen levels in the albino rat, an alternate host, but not in its natural host, the cotton-rat. In the albino rat the primary infection is rejected by about 120 days after infection whereas in the cotton-rat rejection does not occur. Consequently, the drop in hepatic glycogen levels in the albino rat has some correlation with the immune status of the host.

Plasmodium yoelli nigeriensis infection in albino mice significantly altered the hepatic microsomal mixed function oxidase system. Cytochrome P-450 (the terminal monooxygenase) and other monooxygenases, viz. aniline hydroxylase, aminopyrine-N-demethylase and benzo(a)pyrene hydroxylase were significantly lowered while microsomal heme showed 4-fold increase at 80% parasitaemia. Noticeable impairment in the other components like NADH:cytochrome b5 reductase, NADPH:cytochrome c reductase, cytochrome b5 and glucose-6-phosphatase was also observed. Oral treatment of normal and P. y. nigeriensis infected mice with chloroquine (64 mg per kg body weight for 4 days) caused lowering of mixed function oxidase activitied which however showed a recovering trend, a week after cessation of treatment.

Ascaris lumbricoides var. hominis and Ascaridia galli contain 5-hydroxytryptamine, histamine, dopamine, and norepinephrine. The chick parasite showed lower levels of monoamines compared to human ascaris. Amine concentrations in females were higher than in males. In all specimens, 5-hydroxytryptamine was the highest while norepinephrine was found to be uniformly low. The female reproductive organ contained the maximum amount of dopamine while intestine was rich in histamine. A progressive increase in the concentrations of biogenic amines was noticed during development.

Lactate dehydrogenase, E.C.1.1.1.27 (LDH) from the simian malarial parasite, Plasmodium knowlesi, and from normal rhesus monkey erythrocytes has been purified using Blue Sepharose affinity chromatography, and the properties of the purified enzyme from these two sources have been compared. The enzyme from the host and parasite were different in their kinetic properties, viz., substrate and pH optima, thermostability and isoenzymic behaviour. Partially purified LDH of the erythrocytes resolved into three isomeric bands on polyacrylamide gel electrophoresis, whereas the parasite LDH moved as a single enzyme band of different mobility from the host LDH. The molecular mass of the parasite enzyme was estimated as 117,500 daltons.

Some properties of purified lactate dehydrogenase, (EC. 1.1.1.27) from schizonts of Plasmodium knowlesi are described. The plasmodial enzyme migrated as single entity on polyacrylamide gel, and resembled rabbit muscle (M4) lactate dehydrogenase in its electrophoretic mobility. The P. knowlesi enzyme consisted of four identical subunits of 31 kDa. Purified lactate dehydrogenase was inhibited almost completely when incubated with 100 microM p-chloromercuribenzoate, Ag+ or Hg+ and such inhibition could be reversed by the addition of beta-mercaptoethanol or L-cysteine. Metal chelators did not show any remarkable effect. Oxalic acid is a competitive inhibitor of pyruvate reduction by this enzyme with apparent Ki of approximately equal to 0.41 mM.

Extracts of Litomosoides carinii, the cotton rat filarial parasite, possess significant activities of glycogen phosphorylase, phosphoglucomutase, phosphoglucoseisomerase, a nonspecific hexokinase acting on glucose, mannose, galactose and fructose, phosphofructokinase, aldolase, glyceraldehyde phosphate dehydrogenase, enolase, pyruvatekinase, lactate dehydrogenase, phosphoenolpyruvate carboxykinase, and malate dehydrogenase along with phosphatases acting on glucose-6-phosphate and fructose diphosphate. The results indicate the functioning of the glycolytic pathway in this worm which resembles Schistosoma mansoni, a lactic acid producer, in the differential activities of the terminal enzymes of the pathway.

Chlorpromazine (CPZ) caused suppression in release of microfilariae in vitro from Setaria cervi at 10(-5) M concentration. The inhibitory effect of CPZ was further stimulated by Ca2+ (2 mM), whereas addition of EGTA (2 mM) resulted in partial reversal. Addition of dopamine (1 mM) along with CPZ (10(-5) M) caused similar inhibition as was observed in the presence of CPZ (10(-5) M) alone. CPZ did not effect in vitro oxygen uptake by worm homogenates up to 0.5 mM concentration. The results indicate the Ca2+/calmodulin-dependent anthelmintic action of CPZ on S. cervi.