Arrested states formed on quenching spin chains with competing interactions and conserved dynamics

We study the effects of rapidly cooling to T=0 a spin chain with conserved dynamics and competing interactions. Depending on the degree of competition, the system is found to get arrested in different kinds of metastable states. The most interesting of these has an inhomogeneous mixture of interspersed active and quiescent regions. In this state, the steady-state autocorrelation function decays as a stretched exponential approximately exp[-(t/tau(0))(1/3)], and there is a two-step relaxation to equilibrium when the temperature is raised slightly.

Visual pigments and oil droplets in the retina of a passerine bird, the canary Serinus canaria: microspectrophotometry and opsin sequences

The visual receptors of the passeriform bird Serinus canaria, the canary, have been examined microspectrophotometrically and the sequences of the opsins determined. Rods have a maximum absorbance (lambda max) at 506 nm. Four spectral classes of single cone are present: long-wave-sensitive (LWS) containing a photopigment with lambda max at 569 nm, middle-wave-sensitive (MWS) with lambda max at 505 nm, short-wave-sensitive (SWS) with lambda max at 442 nm, and ultraviolet-sensitive (UVS) with lambda max at about 366 nm. Double cones possess the 569-nm pigment in both members. Typical combinations of photopigment and oil droplet occur in most cone classes. An ambiguity exists in the oil droplet of the single LWS cones. In some birds, LWS cones are paired with an R-type droplet, whereas in the majority of canaries the LWS pigment is paired with a droplet similar to the P-type of double cones. Mechanisms of spectral tuning within each opsin class are discussed.

Solid matrix characterization of immobilized Pseudomonas putida MTCC 1194 used for phenol degradation

Characterization studies of calcium alginate beads with encapsulated Pseudomonas putida MTCC 1194, used for the biodegradation of phenol, were carried out to investigate the reactivity, reusability and structural strength of the solid matrix. Various techniques were employed to improve the structural stability of the immobilized solid necessary for its use in commercial reactors like packed bed flow reactor, fluidized bed and CSTR systems. Experiments were performed to establish the optimum conditions for durability, strength and steady biochemical reactivity. During a batch run of 40 h a gradual decline in the rate of phenol degradation was observed with the immobilized system. The calcium alginate beads with high structural strength yielded decreased activity. Treatment with a hardening agent like glutaraldehyde for different concentrations and treatment times led to variations in structural stability, reusability and the extent of phenol degradation. Scanning electron microscope studies of the immobilized solid indicated the internal distribution pattern of the cells encapsulated in a calcium alginate bead.

Hepatic sarcoidosis and renal carcinoma

Sarcoidosis is a relatively common, chronic, multisystem disease of unknown origin. It most commonly affects young adults and usually manifests with bilateral hilar lymphadenopathy or pulmonary infiltrates. Alternatively, it may present with protean manifestations. It has been documented in all organs of the body, with the exception of the adrenal gland. We describe a male patient who presented with hepatic sarcoidosis, with a sclerosing cholangitis-like picture, but without any pulmonary involvement. He was treated with prednisolone and cyclophosphamide, the latter as a steroid-sparing agent. A few years later, renal adenocarcinoma developed. We postulate that this could be related to cyclophosphamide treatment. We present this case history for two reasons: (1) sarcoidosis, selectively affecting the liver and lymph nodes but not the lung, with its hepatic involvement mimicking sclerosing cholangitis, has not previously been reported: and (2) although long-term cyclophosphamide treatment is known to be associated with malignancy, there is only one previous report of its association with a renal adenocarcinoma.

Management of glass intraocular foreign bodies

PURPOSE

To describe the results of management of glass intraocular foreign bodies (IOFBs).

METHODS

A total of 51 eyes of 43 patients that sustained penetrating injury with glass IOFB were studied retrospectively. A total of 23.5% had IOFB only in the anterior segment; the rest had IOFB in the posterior segment alone or in both the anterior and posterior segments. Six eyes were followed conservatively despite IOFB in a functional eye. Removal of IOFB was combined with repair of retinal detachment (where present) using internal tamponade with gas or silicone oil or buckle.

RESULTS

After a mean follow-up of 16.8 months, 66.7% of eyes recovered better than 6/60 (20/200) vision and 75.6% had attached retina. On univariate analysis, scleral entry wound, posterior segment IOFB, larger size of IOFB, and retinal damage were found to be associated with poor anatomic outcome. Lower presenting visual acuity, hyphema, retinal damage, subretinal hemorrhage, detached retina, and larger IOFB were associated with a poor functional result. Multivariate analysis identified retinal damage caused by the foreign body as the only factor significantly associated with poor anatomic as well as functional outcome.

CONCLUSIONS

Glass IOFBs are caused in a majority of cases by blast injury. Bilaterality is not uncommon. Presence of retinal damage is predictive of poor functional and anatomic results. Overall results are modest with modern vitreoretinal surgical techniques.

Cognitive decline in patients on an acute geropsychiatric unit

The authors compared patients in a geropsychiatric unit who showed marked cognitive decline during hospitalization with those who did not. Patients who declined in cognitive function were older, were more likely to have a diagnosis of dementia, and were more anergic on admission. These patients were also discharged to more restrictive living environments. The subgroup of demented patients who declined in cognitive function were also older and improved less on anxiety and depression.

Setaria digitata adult 14- to 20-kDa antigens induce differential Th1/Th2 cytokine responses in the lymphocytes of endemic normals and asymptomatic microfilariae carriers in bancroftian filariasis

High titers of parasite antigen-specific IgG4 antibodies have been found to be circulating in the peripheral blood of chronic patients, asymptomatic microfilariae carriers, and endemic normals in bancroftian filariasis. But in contrast to this, the titers of antigen-specific IgG1, IgG2, and IgG3 isotype antibodies are much lower. Using soluble antigens of adult Setaria digitata, a cattle parasite which shows strong antigenic reactivity with filaria sera, we have identified, by immunoblot, 14- to 20-kDa antigens which are recognized only by the IgG4 isotype antibodies present in the sera of asymptomatic microfilariae carriers. These 14- to 20-kDa antigens, after fractionation by SDS-PAGE and transfer to nitrocellulose paper, when solubilized and tested in vitro, induced secretion of a higher quantity of IFN-gamma and a lower quantity of IL-4, IL-5, and IL-10 (differential Th1 and Th2 response) in the lymphocytes of endemic normals in comparison to what they induced in the lymphocytes of asymptomatic microfilariae carriers.

The molecular basis for UV vision in birds: spectral characteristics, cDNA sequence and retinal localization of the UV-sensitive visual pigment of the budgerigar (Melopsittacus undulatus)

Microspectrophotometric (msp) studies have shown that the colour-vision system of many bird species is based on four pigments with absorption peaks in the red, green, blue and UV regions of the spectrum. The existence of a fourth pigment (UV) is the major difference between the trichromacy of humans and the tetrachromacy of such birds, and recent studies have shown that it may play a determining role in such diverse aspects of behaviour as mate selection and detection of food. Avian visual pigments are composed of an opsin protein covalently bound via a Schiff-base linkage to the chromophore 11-cis-retinal. Here we report the cDNA sequence of a UV opsin isolated from an avian species, Melopsittacus undulatus (budgerigar or small parakeet). This sequence has been expressed using the recombinant baculovirus system; the pigment generated from the expressed protein on addition of 11-cis-retinal yielded an absorption spectrum typical of a UV photopigment, with lambdamax 365+/-3 nm. This is the first UV opsin from an avian species to be sequenced and expressed in a heterologous system. In situ hybridization of this sequence to budgerigar retinas selectively labelled a sub-set of UV cones, representing approx. 9% of the total cone population, that are distributed in a semi-regular pattern across the entire retina.

Oxidative inactivation of gastric peroxidase by site-specific generation of hydroxyl radical and its role in stress-induced gastric ulceration

We have shown earlier that restraint-cold stress-induced gastric ulceration in rats is caused by metal ion-dependent generation of hydroxyl radical (OH.) and oxidative inactivation of the gastric peroxidase (GPO), an important H2O2 scavenging enzyme. To study the mechanism of the oxidative damage of GPO, the purified enzyme was exposed to an OH. generating system containing Cu2+, ascorbate, and H2O2. Kinetic studies indicate that the enzyme is inactivated in a time-dependent process showing saturation with respect to Cu2+ concentration. The enzyme specifically requires Cu2+ and is not inactivated by the same concentration of Fe2+, Mn2+, or Zn2+. Sensitivity to catalase indicates the critical role of H2O2 in the inactivation. Inactivation is insensitive to superoxide dismutase, suggesting no role of superoxide. The rate of inactivation is not increased in D2O excluding the involvement of singlet oxygen in the process. However, OH. scavengers such as benzoate or mannitol cannot prevent inactivation. The results indicate a plausible generation of OH. within the enzyme molecule as the cause of inactivation. Fragmentation of peptide linkage or intramolecular crosslinking, gross change of tertiary structure, or change in intrinsic tryptophan fluorescence which occurs in "global" oxidation are not evident. Inactivation is dependent on pH and from a plot of K(obs) of inactivation against pH, the controlling role of an ionizable group of the enzyme having a pka of 7.8 could be suggested, deprotonation of which favors inactivation. Amino acid analysis shows a specific loss of two lysine residues in the inactivated enzyme. Competitive kinetic studies indicate that pyridoxal phosphate, a specific modifier of the lysine residue, prevents inactivation by competing with Cu2+ for binding at the GPO. A Cu2+ binding motif consisting at least of two lysine residues exists in GPO, which specifically binds Cu2+ and generates OH.. The radical oxidizes the lysine residues and perturbs the heme environment to cause inactivation. We suggest that oxidative damage of GPO is mediated by site-specific generation of OH. and not by the OH. generated in the bulk phase.

Specific binding of inorganic mercury to Na(+)-K(+)-ATPase in rat liver plasma membrane and signal transduction

Specific binding of Hg2+ to ouabain-sensitive Na(+)-K(+)-ATPase of rat liver plasma membrane was demonstrated with a Ka of 2.64 x 10(9) and Bmax of 1.6 nmole mg-1 protein. The binding of mercury to the enzyme also causes significant inhibition of the enzyme, which is greater than its ouabain sensitivity. In the cytosol Hg2+ binding to reduced glutathione (GSH) is stimulated by GSH-S-transferase (GST), the activity of which was found to be significantly enhanced by 15 mM Na+ and 10 mM Hg2+. It is proposed that the transport of Hg2+ inside the cell takes place by increased dissociation of Hg2+ from the membrane due to greater avidity of Hg2+ towards cytosolar GSH binding. The GSH-Hg complex enters the nucleus where it dissociates to bind the metal response element (MRE) of the metallothionein (MT) gene to induce MT transcription.

Aortoarteritis involving supra-aortic trunks: a profile of six cases

Six patients (2 male, 4 female; age range 24 to 36 years) with aortoarteritis involving the supra-aortic trunks were investigated and surgically managed by bypass graft with either preclotted dacron or polytetrafluoroethylene (PTFE) in an urban institute. There has been no mortality and post-operative functional recovery has been satisfactory in all the cases.

Role of exogenous reduced glutathione on time dependent 203Hg distribution in liver and kidney of a freshwater teleost, Anabas testudineus

Time-dependent tissue distribution of mercury(Hg) was studied in a freshwater perch, Anabas testudineus which revealed that the liver and kidneys are the major sites of Hg retention. The role of reduced glutathione (GSH) in the clearance of Hg was also investigated to evaluate the ameliorative effect of this nucleophile. For this purpose, the perch was given GSH 15 min before or after they received 203Hg by injection. The fish were then sacrificed at 24 h and 48 h later. The results clearly indicate that exogenous GSH can significantly reduce Hg retention in both the liver and kidneys, demonstrating a direct role of this nucleophile in the amelioration of Hg-induced toxicity in the early phase of intoxication.

Biochemical and immunological characterization of soluble antigens of Giardia lamblia

The crude soluble antigens (CSA) of Giardia lamblia trophozoites and their analytically purified fractions were characterized biochemically and immunologically to determine the most immunogenic fraction and its localization on the parasite. Both Sephacryl S-300 column chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed the highly complex and heterogeneous nature of CSA. Gel filtration of CSA showed four fractions (FI-FIV) with molecular masses of 250, 150, 110, and 10 kDa for fractions I-IV, respectively. Protein profiles of CSA demonstrated 28 Coomassie-blue bands in the range of 200-14 kDa. Similar banding patterns with fewer polypeptides were observed in the FI fraction. However, fractions II and III showed polypeptide bands in the region of 97-14 kDa. The glycoprotein nature of CSA and its-fractions were demonstrated in physicochemical analysis. In antigenic activity analysis the high-molecular-weight FI antigen was found to be 8 times more immunogenic than CSA as well as the other fractions. Major differences in the immunoreactivity of CSA and FI antigens were noted at 220, 30, and 22 kDa for the FI antigen and at 205, 84, 55, 43, and 20 kDa for CSA. Some of these FI polypeptides were found to be surface-associated as revealed by immunofluorescence and immunoblot assay. These results suggest the future use of the FI antigen in the serodiagnosis of and immunoprophylaxis against giardiasis.

Hydroxyl radical is the major causative factor in stress-induced gastric ulceration

The role of the metal-catalyzed production of hydroxyl radicals (OH.) on gastric ulceration caused by restraint-cold stress in rat was studied. Stress causes a 50% increase in the thiobarbituric acid reactive species (TBARS) as a measure of the lipid peroxidation, nearly 70% increase in protein oxidation as measured by its carbonyl content and about 40% decrease in the glutathione content of the fundic stomach, suggesting oxidative damage by stress. Stress also causes a time-dependent increase in the mitochondrial superoxide dismutase activity and a decrease in the peroxidase activity, both of which correlate well with the increase in the severity of ulceration as measured by the ulcer index. Specific OH. scavengers such as benzoate or dimethylsulfoxide (DMSO) and the free radical trap such as alpha-phenyl N-tert-butyl nitrone (PBN) significantly inhibit gastric ulceration suggesting the role of OH. in this oxidative damage. Desferrioxamine (DFO), a nontoxic transition metal ion chelator, protects the mucosa against stress-ulceration dose dependently. Increased level of TBARS and the inactivation of gastric peroxidase are also prevented by DFO or by antioxidants such as glutathione or vitamin E, suggesting the critical role of metal ion and OH. in the oxidative damage. A metal-catalyzed OH. generating system constituted by Cu2+, H2O2 and ascorbate (reducing equivalent of O2-) causes inactivation of the purified gastric peroxidase in vitro, which can be effectively prevented by DFO. The stress-induced activation of the superoxide dismutase is completely blocked by pretreatment with alpha-amanitin indicating an increased synthesis of the enzyme by increased transcription of its m-RNA. Quantitative measurement indicates that stress causes a fivefold increase in the generation of OH., which correlates well with the increase in ulcer index with the progress of stress. The results indicate that the stress-induced gastric ulceration is a consequence of the oxidative damage of the gastric mucosa. This is caused by the OH. generated through the metal-catalyzed Haber-Weiss reaction between O2- and H2O2, the latter being formed by the stimulation of the superoxide dismutase and inactivation of the gastric peroxidase.

Thermostable alpha-amylase production using Bacillus licheniformis NRRL B14368

Maximum amount of extracellular alpha-amylase of B. licheniformis NRRL B14368 was obtained at the stationary phase. Highest yield of alpha-amylase was achieved with high level of crude protein and low carbohydrate level. There was a catabolite repression in the organism. Protease was produced concurrently with alpha-amylase. It was also observed that soyabean acts as an inhibitor of the protease. Optimum pH and temperature of alpha-amylase were 5-7 and 76 degrees C respectively. It was also observed that alpha-amylase production was a non-growth associated product. Maltose was an excellent inducer for alpha-amylase production. Ca2+ (0.01 M) increased the thermostability of the enzyme. Alpha-amylase purification studies were carried out by using isopropanol, acetone, ammonium sulphate solution, ion exchange chromatography. Acetone was found most suitable for the separation of alpha-amylase. Protein recovery and relative enzyme activity (as compared to that of the maximum activity of the crude enzyme) were 30.77% and 3.03 respectively.

Arsenic in groundwater in six districts of West Bengal, India

Arsenic in groundwater above the WHO maximum permissible limit of 0.05 mg l(-1) has been found in six districts of West Bengal covering an area of 34 000 km(2) with a population of 30 million. At present, 37 administrative blocks by the side of the River Ganga and adjoining areas are affected. Areas affected by arsenic contamination in groundwater are all located in the upper delta plain, and are mostly in the abandoned meander belt. More than 800 000 people from 312 villages/wards are drinking arsenic contaminated water and amongst them at least 175 000 people show arsenical skin lesions. Thousands of tube-well water in these six districts have been analysed for arsenic species. Hair, nails, scales, urine, liver tissue analyses show elevated concentrations of arsenic in people drinking arsenic-contaminated water for a longer period. The source of the arsenic is geological. Bore-hole sediment analyses show high arsenic concentrations in only few soil layers which is found to be associated with iron-pyrites. Various social problems arise due to arsenical skin lesions in these districts. Malnutrition, poor socio-economic conditions, illiteracy, food habits and intake of arsenic-contaminated water for many years have aggravated the arsenic toxicity. In all these districts, major water demands are met from groundwater and the geochemical reaction, caused by high withdrawal of water may be the cause of arsenic leaching from the source. If alternative water resources are not utilised, a good percentage of the 30 million people of these six districts may suffer from arsenic toxicity in the near future.

Pattern of uveitis in a referral uveitis clinic in India

This report describes a retrospective study of all new patients in our uveitis clinic between January 1992 and December 1994, undertaken to identify the pattern of uveitis in the Indian subcontinent. A standard clinical protocol, and the naming-meshing system with tailored laboratory investigations were used to arrive at a final uveitic diagnosis. Uveitis comprised 1.5% of new cases seen at the centre. Out of 1,273 uveitis cases, anterior uveitis was the most common type (39.28%), followed by posterior uveitis (28.75%), intermediate uveitis (17.44%), and panuveitis (14.53%). The most commonly affected age group were patients in their forties (23.57%). Uveitis was less common in children below 10 years (3.61%) and in adults over 60 years of age (6.44%). Men (62.21%) were more commonly affected than women (37.79%). Aetiology remained undetermined in 59.31% of cases. Anterior uveitis was most commonly idiopathic (58.6%). The most common cause of posterior uveitis was toxoplasmosis (27.87%), and that of panuveitis was the Vogt-Koyanagi-Harada syndrome (21.08%). A higher incidence of microbiologically proven tubercular uveitis (5 cases), and uveitis due to live intraocular nematode (4 cases), and malaria (1 case), were seen, in contrast to other studies. Only 2 cases of AIDS with ocular lesions were seen. This paper reveals the pattern of uveitis seen at a major referral eye institute in India.

Studies on glucoamylase produced from Aspergillus awamori (NRRL-3112) and their effect on saccharification of potato starch

Efficiency of an enzymatic starch saccharification process depends not only on the activity of the glucoamylase but also its purity. About 96.82% unwanted proteins present in 2-day old culture broth of A. awamori NRRL-3112 (grown in MYGP medium) were separated by precipitation with ammonium sulphate which was followed by dialysis. More than 80% activity of the glucoamylase was recovered. Three protein fractions (A, B, C) were identified using gel permeation chromatography. Fractions A and B showed comparatively higher glucoamylase activity than fraction-C. Moreover, fraction-B showed no product inhibition. The optimum temperature and pH of the purified enzyme (fraction-B) were 60 degrees C and 4.0 respectively. The saccharification efficiency of potato pulp was more in case of using purified glucoamylase (fraction-B) as compared to that of crude enzyme.

Pattern of uveitis in a referral uveitis clinic in India

The pattern of uveitis changes over time with the emergence or identification of new uveitic entities. The aim of this prospective study was to obtain a correct incidence pattern and aetiology of uveitis cases seen in a uveitis clinic. We studied all new uveitic cases seen in a-one year period. A standard clinical protocol was followed for each case. Of the 465 new uveitic cases, anterior uveitis was most commonly encountered (170 cases, 36.5%), followed by posterior uveitis (132 cases, 28.4%), intermediate uveitis (92 cases, 19.8%) and panuveitis (71 cases, 15.3%). The aetiology remained undetermined in majority of the cases (58.7%): anterior uveitis (48.8%), posterior uveitis (45.45%), panuveitis (53.52%). The most common cause was collagen disease (29.4%) in anterior uveitis; toxoplasmosis (30.3%) in posterior uveitis; and Vogt-Koyanagi Harada's disease (25.35%) in panuveitis.

Arsenic in ground water in six districts of West bengal, India: the biggest arsenic calamity in the world. Part 2. Arsenic concentration in drinking water, hair, nails, urine, skin-scale and liver tissue (biopsy) of the affected people

In six districts of West Bengal arsenic has been found in ground water above the maximum permissible limit recommended by the WHO of 0.05 mg l-1. This water is used by the villagers for drinking, cooking and other household purposes. These six districts have an area of 34,000 km2 and hold a population of 30 million. Over the last five years we have surveyed only a few small areas of these six affected districts and our survey revealed that, at present, at least 800,000 people from 312 villages in 37 blocks are drinking contaminated water and more than 175,000 people are showing arsenical skin lesions that are the late stages of manifestation of arsenic toxicity. Most of the three stages of arsenic-related clinical manifestations are observed amongst the affected people. The common symptoms are conjunctivitis, melanosis, depigmentation, keratosis and hyperkeratosis; cases of gangrene and malignant neoplasms are also observed. The source of arsenic is geological. We have analysed thousands of arsenic contaminated water samples. Most of the water samples contain a mixture of arsenite and arsenate and in none of them could we detect methylarsonic or dimethylarsenic acid. We have also analysed a large number of urine, hair and nail samples, several skin-scales and some liver tissues (biopsy samples) of the people drinking the arsenic contaminated water and showing arsenical skin lesions. Flow injection hydride generation atomic absorption spectrometry (FI-HGAAS) was used for the analysis of hair, nails, urine and skin-scale after decomposition by various techniques. The liver tissues were analysed by Zeeman corrected-ETAAS using a few milligrams of the biopsy samples.

Isolation of microfilariae and eggs of Setaria digitata

A simple procedure of gel-filtration was used to purify microfilariae of the cattle parasite, Setaria digitata from its eggs. The eggs of S. digitata were also isolated from the female worms by picking out the uterine canal. Gel-filtration gave a recovery of 70% for microfilariae.

Thiocyanate, a plausible physiological electron donor of gastric peroxidase

Gastric peroxidase (GPO) was purified to apparent homogeneity to characterize its major physiological electron donor. The enzyme (RZ = 0.7), with a subunit molecular mass of 50 kDa, is a glycoprotein, with a relative abundance of aspartic and glutamic acid over arginine and lysine. It has a Soret maximum at 412 nm, which is shifted to 426 nm by H2O2 due to formation of compound II. Although the physiological electron donors I-, Br- and SCN-, but not Cl-, are oxidized by GPO optimally at acid pH, only I- and SCN- are oxidized appreciably at physiological pH. Considering that the I- concentration in stomach is less than 1 microM, whereas the SCN- concentration is about 250 microM, SCN- may act as a major electron donor for GPO. Moreover, SCN- oxidation remains unaltered in the presence of physiological concentrations of other halides. The second-order rate constant for the reaction of GPO with H2O2 (k1) and compound I with SCN- (k2) at pH 7 was found to be 8 x 10(7) M-1.s-1 and 2 x 10(5) M-1.s-1 respectively. GPO has significant pseudocatalase activity also in the presence of I- or Br-, but it is blocked by SCN-. The SCN- oxidation product OSCN- may be reduced back to SCN- by cellular GSH, and GSSG may be reduced back to GSH by glutathione reductase and NADPH. In a system reconstituted with pure glutathione reductase, NADPH, GSH, SCN- and H2O2. GPO-catalysed SCN- oxidation could be coupled to NADPH oxidation. This system where GPO utilizes SCN- as the major physiological electron donor may operate efficiently to scavenge intracellular H2O2.

Comparative study of the effects of mu, delta and kappa opioid agonists on 3H-dopamine uptake in rat striatum and nucleus accumbens

The effect of the mu opioid agonist DAGO, delta opioid agonist DPDPE and kappa opioid agonist U50,488H on 3H-dopamine (3H-DA) uptake was studied in synaptosomes prepared from rat striatum and nucleus accumbens. Over the range of concentrations tested (1 nM-10 microM) DAGO and DPDPE were devoid of effects on 3H-DA uptake in the striatum and the nucleus acumbens. In contrast, U50,488H significantly decreased 3H-DA uptake in both structures. The inhibition of uptake induced by the kappa agonist was not reversed in the presence of the opiate antagonists naloxone (10 microM) or nor-binaltorphimine (0.1 microM). Dynorphin A (1-13) also induced a significant reduction in 3H-DA uptake in both structures at the concentrations of 10 and 30 microM. This inhibitory effect was not reversed by naloxone (10 microM). These data suggest that kappa opioid agonists modulate dopamine uptake in the striatum and the nucleus accumbens and their effects may not be due to an activation of opioid receptors.

Production and characterization of monoclonal antibodies against a highly immunogenic fraction of Entamoeba histolytica (NIH:200) and their application in the detection of current amoebic infection

Six monoclonal antibodies (MAbs) were produced against a highly immunogenic fraction derived by the chromatographic separation of the soluble preparation of axenic Entamoeba histolytica (strain NIH:200) trophozoites. Isotype characterization of the six MAbs revealed that four belonged to the IgM class and one each to the IgG1 and the IgG2a subclasses. The immunoreactivity patterns and the specificity of the MAbs with homologous and heterologous antigens were analyzed by the enzyme-linked immunotransfer blot technique and by the enzyme-linked immunosorbent assay. The MAbs reacted intensely with isolates of E. histolytica (strain NIH:200 as well as a local isolate MX1) but showed no reactivity with Entamoeba coli, Iodamoeba butschlii, Endolimax nana, Entamoeba hartmanni, free-living amoeba (Acanthamoeba harticolus) and other enteric parasites. Using the IgG1 MAb as a detecting antibody, a polyclonal-monoclonal antibody-based enzyme-linked immunosorbent assay was developed for the detection of E. histolytica antigens in stool samples of infected patients. The detection limit of the assay was 8 ng of amoebic antigen. This test was found to be specific and sensitive and yielded 100% positive results in cases with amoebiasis but did not react with controls included in the evaluation. The MAb-based enzyme-linked immunosorbent assay developed in this study will be an important test for the diagnosis of E. histolytica in the feces of infected humans; however, the limitation of the test is the inability to discriminate the pathogenic status of the amoeba detected in the stool.

Effect of stress on the antioxidant enzymes and gastric ulceration

The effect of cold-restraint stress on the antioxidant enzymes of the rat gastric mucosa was studied with a view to finding out their role in stress induced gastric ulceration. Histological examination revealed stress induced extensive damage of the surface epithelial cell with lesions extending up to submucosa in some cases. Stress causes time-dependent increase in histamine and pepsin content but decrease in acid content of the gastric fluid with the progress of ulceration (ulcer index) for two hours. The tissue lipid peroxidation was significantly increased as evidenced by accumulation of malondialdehyde. Since lipid peroxidation results from the generation of reactive oxygen species, stress effect was studied on some antioxidant enzymes such as superoxide dismutase, peroxidases and prostaglandin synthetase as a function of time. The time dependent increase in stress ulcer correlates well with the concomitant increase in superoxide dismutase activity and decrease in peroxidase and prostaglandin synthetase activity. This creates a favourable condition for accumulation of endogenous H2O2 and more reactive hydroxyl radical (OH.). Administration of antioxidants such as reduced glutathione or sodium benzoate prior to stress causes significant decrease in ulcer index and lipid peroxidation and protection of gastric peroxidase activity suggesting the involvement of reactive oxygen species in stress induced gastric ulceration. This is supported by the in vitro observation that OH. can also inactivate peroxidase and induce lipid peroxidation. As prostaglandin is known to offer cytoprotection, stress-induced loss of prostaglandin synthetase activity appears to aggravate the oxidative damage caused by reactive oxygen species.

Biochemical and immunological studies on soluble antigens of Entamoeba histolytica

The soluble antigens of Entamoeba histolytica trophozoites were analysed in detail by biochemical and immunochemical methods. The antigen was highly complex and heterogeneous as revealed by Sephacryl S-300 column chromatography, which showed four distinct fractions. The molecular mass of fractions FI, FII, FIII and FIV was 660, 170, 65 and 13 kDa, respectively. Protein was the major constituent in crude soluble antigen (CSA) and fractions FI and FII (67%, 80% and 90%, respectively). Polysaccharide was predominant in the FIII fraction (59%). Antigenic activity observed after different physico-chemical treatments revealed that CSA and FI antigens were predominantly glycoprotein in nature. However, the antigenicity of FIII antigen was greatly reduced after sodium meta-periodate treatment, whereas no alteration in reactivity was discerned after trypsin treatment. Sodium dodecyl sulphate-polyacryl-amide gel electrophoresis (SDS-PAGE) analysis demonstrated nearly 28 Coomassie blue bands for CSA and 20, 16, 15 and 3 polypeptide bands for the FI, FII, FIII and FIV fractions, respectively. The molecular mass of the polypeptides of these bands ranged from 210 to 20 kDa. Antigenic activity was observed in CSA and in the first three fractions, both in counter immunoelectrophoresis (CIEP) and in enzyme-linked immunosorbent assay (ELISA). However, the highest antigenic activity was noted in fraction FI. Major immunoreactive polypeptides of CSA and FI antigens against whole trophozoite antibody were observed in the 10- to 170-kDa regions. However, major differences in the immunoreactivity of the two antigens were noted at 116 and 14 kDa for FI antigen and at 84, 30 and 20 kDa for CSA.(ABSTRACT TRUNCATED AT 250 WORDS)

A study of ground water contamination by arsenic in the residential area of Behala, Calcutta due to industrial pollution

Due to the discharge of industrial effluent after production of the insecticide Paris-Green [Copper acetoarsenite Cu(CH(3)COO)(2).3Cu(AsO(2))(2)] by a local factory at the P. N. Mitra Lane, Behala, ground water has become contaminated with arsenic. More than seven thousand people were using this arsenic contaminated tube-well water for drinking and house-hold purposes. Many people of the area were hospitalised and symptoms of arsenic toxicity were visible amongst a large number of the population. Analytical study reveals that soil around the area of effluent dumping point, which is at the middle of the locality, contains a very high concentration of arsenic and copper. For the last 20 years this factory had been producing 20 tons of Paris-Green per year and had been dumping its effluent in that area. It seems, the effluent treatment for arsenic removal was not adequate and finally arsenic percolated to the underground aquifers. Consequently, arsenic concentration in the ground water is very high. Both arsenite and arsenate are present in ground water. An alternate source of water other than the ground water is immediately necessary for the people of P. N. Mitra Lane.

Environmental pollution and chronic arsenicosis in south Calcutta

Careless handling of industrial wastes often creates problems for human health and the environment. Chronic arsenic toxicity, resulting from household use of arsenic-contaminated water occurred in 53 out of 79 members (67%) of 17 families residing in South Calcutta close to a factory that manufactured Paris-green (copper acetoarsenite). Clinical investigation of 20 of these affected persons showed typical skin pigmentation as well as palmar and plantar keratosis in all of them, while gastrointestinal symptoms, anaemia and signs of liver disease and peripheral neuropathy were seen in many. The water used by the affected families for drinking and cooking had been taken from shallow tubewells and had arsenic levels from 5.0 to 58 mg/l (WHO permissible limit, 0.05 mg/l). Other residents in the same area whose drinking-water came from deep tubewells or from tap water supplied by the Calcutta Municipal Corporation (arsenic levels, less than 0.05 mg/l) were not affected. The study confirms that arsenic in the shallow tubewells was due to the waste discharged by the factory producing Paris-green.

Characterization and histopathological correlation of cytosol proteins of benign and malignant breast tumors

Significant differences in cytosol protein level exist between normal/benign and cancerous breast tissues. There is a positive correlation between the cytosol protein level and histological grade of carcinoma. Well-differentiated carcinoma have a lower value of cytosol protein than poorly differentiated carcinoma. In slab gel electrophoregrams, the total numbers of bands are almost identical in normal, benign, and malignant conditions. In addition, 37 Kd protein band is consistently present in malignant cases and always absent in normal or benign cases. More extensive biophysical examination of this band may provide further insight into the protein alterations in cancer cells at the molecular level.

Renal papillary necrosis in the east coast of Peninsular Malaysia

Six hundred and one intravenous Urograms (IVU) done at the General Hospital, Kuala Trengganu from 1981 to 1985 were reviewed retrospectively for Renal Papillary Necrosis (RPN). It was found that 1.3% of IVUs had RPN. There was a higher incidence of RPN amongst males as compared to females. RPN occurred more commonly in the younger age groups.

Soft neurological signs and EEG pattern in rural malnourished children

The present study was carried out in 208, 8-10 yr old male, rural, primary school children of Kashi Vidyapith Block, Varanasi. These children were examined for anthropometry, soft neurological signs and electroencephalographic pattern. It was found that the presence of soft neurological signs was related to the severity of malnutrition. The relationship between nutritional status and motor tasks showed that the performance in successive finger tapping, toe tapping, heel toe tapping, hand patting and alternating hand pronation supination in both hands while finger tapping with the right, was significantly affected. The EEG pattern in 16 children with soft neurological signs showed abnormalities in the form of slow and sharp waves, particularly in the frontal lobe, but also in the parietal and temporal lobes. The motor deficits were more marked on the contralateral side of the EEG abnormality.

Rectal palpation and transrectal fine needle aspiration of the prostate in the monitoring of prostate cancer: a study of 59 patients during treatment with estramustine phosphate or estrogens

Fifty-nine hormonally treated prostatic carcinoma patients were prospectively followed by rectal palpation and fine needle aspiration cytology (FNAC) at 6 month intervals for periods ranging from 6 to 120 months (median follow-up, 48 months). The cytologic impressions and palpatory findings were divided into four categories, respectively, ranging from benign to clearly malignant. Cytologic material and palpatory descriptions suitable for evaluation were available for 306 follow-up examinations, with a mean number of follow-up examinations per patient of five (range, 1-13). Tumor relapse was noted in 26 patients and was diagnosed at the same time by FNAC and palpation in six patients. In 16 of the patients tumor progression was first noted by cytology, and in four patients relapse was first detected by rectal palpation. Different patterns of cytologic and palpatory findings during the development of remission and progression of the tumors and drawbacks of the methods are discussed.