Detection of human neuronal α7 nicotinic acetylcholine receptors by conjugates of snake α-neurotoxin with quantum dots.

Fluorescent derivatives are widely used to study the structure and functions of proteins. Quantum dots (QDs), fluorescent semiconductor nanocrystals, have a high quantum yield and are much more resistant to bleaching compared to organic dyes. Conjugates of α-neurotoxins with QDs were used for visualization of human α7 acetylcholine receptors heterologously expressed in GH4C1 pituitary adenoma cells. Specific staining of cells by the conjugated toxins was observed.

Musculoskeletal problems and fluoride exposure: A cross-sectional study among metal smelting workers.

Frequent and repetitive activities in job and awkward postures are shown as major contributors of musculoskeletal problems in most of the occupational health studies; however, efforts to explore newer risk factor are important to plan interventional measures. In this backdrop, this study examined contribution of fluoride exposure to musculoskeletal complaints. A cross-sectional interviewer-administered questionnaire survey was conducted involving 180 randomly selected subjects from a metal smelting industry. Clinical examination of the subjects was also performed to assess their health status and morbidity details. Assessment of personal exposure to particulate and gaseous fluoride at workplace was conducted. Urinary fluoride level was also examined in post-shift samples collected from study subjects. The mean age of the study subjects was 39.1 (±6.7) years. Majority of the workers (42.5%) were engaged in pot room. About 54% workers were suffering from backache and 66% subjects had joint pain. Exposure of workers to both particulate and gaseous fluoride and post-working shift urinary fluoride level was significantly higher in pot-room workers in comparison with all other workers. It was observed that age (odds ratio (OR): 1.62; 95% confidence interval (CI): 1.18-2.34), drinking untreated water (OR: 1.51; 95% CI: 1.03-2.76), working in pot room (OR: 1.44; 95% CI: 1.13-1.91) and urinary fluoride level (OR: 2.71; 95% CI: 1.81-3.75) had significant effects on musculoskeletal complaints. This study concludes that along with other predictors such as nature of work, posture at work and age of worker, exposure to fluoride also has significant role in the occurrence of musculoskeletal morbidity.

A Case of Emphysematous Pyelonephritis.

Emphysematous pyelonephritis is a rare but dangerous condition in patients with D.M. and urinary tract infection. We report a case of emphysematous pyelonephritis who presented to us with acute abdomen and sepsis. Her CT abdomen showed air in the collecting system of left kidney. She was managed with, I. V. fluids, antibiotics, insulin, and percutaneous nephrostomy. But she died on the 3rd day of hospitalisation due to Multiorgan failure with sepsis.

Mixing ratios of carbonyls and BTEX in ambient air of Kolkata, India and their associated health risk.

Mixing ratios of 15 carbonyls and BTEX (benzene, toluene, ethyl benzene, xylenes) were measured for the first time in ambient air of Kolkata, India at three sites from March to June 2006 and their photochemical reactivity was evaluated. Day and nighttime samples were collected on weekly basis. Formaldehyde was the most abundant carbonyl (mean concentration ranging between 14.07 microg m(-3) to 26.12 microg m(-3) over the three sites) followed by acetaldehyde (7.60-18.67 microg m(-3)) and acetone (4.43-10.34 microg m(-3)). Among the high molecular weight aldehydes, nonanal showed the highest concentration. Among the mono-aromatic VOCs, mean concentration of toluene (27.65-103.31 microg m(-3)) was maximum, closely followed by benzene (24.97-79.18 microg m(-3)). Mean formaldehyde to acetaldehyde (1.4) and acetaldehyde to propanal ratios (5.0) were typical of urban air. Based on their photochemical reactivity towards OH. radical, the concentrations of the VOCs were scaled to formaldehyde equivalent, which showed that the high molecular weight carbonyls and xylenes contribute significantly to the total OH-reactive mass of the VOCs. Due to the toxic effect of the VOCs studied, an assessment for both cancer risk and non-cancer hazard due to exposure to the population were calculated. Integrated life time cancer risk (ILTCR) due to four carcinogens (benzene, ethyl benzene, formaldehyde and acetaldehyde) and non-cancer hazard index for the VOCs at their prevailing level were estimated to be 1.42E-04 and 5.6 respectively.

Impact of cadmium and lead on Catharanthus roseus--a phytoremediation study.

The Madagascar Periwinkle, Catharanthus roseus (L.) G. Don (a valued medicinal plant) was exposed to different concentrations ofheavymetals like, CdCl, and PbCl, with a view to observe their bioaccumulation efficiency. Germination was inhibited by both the heavy metals in the seeds previously imbibed in GA, and KNO, for 24 hr. EC50 (the effective concentration which inhibits root length by 50%) was recorded as 180 microM for CdCl2, and 50 microM for PbCl2. Both alpha-amylase and protease activity were reduced substantially on treatment of seeds with increasing concentrations of CdCl2, and PbCl2. Malondialdehyde (MDA) a product of lipoxigenase (LOX) activity also increased due to the treatment of both CdCl, and PbCl2. When two-months-old plants grown in normal soil were transferred to soils containing increasing amounts of these two heavy metals, senescence of lower leaves and extensive chlorosis were noticed after four days of transfer However, plants gradually acclimatized and after 20 days the chlorophyll content was almost comparable to normal. Plants receiving CdCl2 treatment (250 microg g(-1) and less) became acclimatized after two weeks and started normal growth. But PbCl2 of 432 microg g(-1) and less could not affect the plant growth throughout, after a preliminary shock was erased. In case of CdCl2 treatment, a stunted growth with reduced leaf area, reduced biomass and sterility were recorded after six months, while plants show normal growth and flowering in case of PbCl2 treatment. Total alkaloid was also found to be decreased in the roots of CdCl2 treated plants. No change was observed in case of PbCl2. GA3 treatments to the CdCl2 treated plants show internode elongation and increase in leaf area with relatively elongated leaves and thinning of stem diameter AAS analyses of leaves of treated plants exhibited 5-10% accumulation of cadmium, but there was no accumulation of lead at all.

Association of cap binding protein-related polypeptides with cytoplasmic RNP particles of chick embryonic muscle.

Cap binding protein (CBP)-related polypeptides were identified in different cytoplasmic RNP particles of embryonic chick muscles using monoclonal antibody to purified CBP. A single immunoreactive peptide (Mr 78 000) was present in preparations of both free mRNP particles and a novel 10 S translation inhibitory RNP particle. In contrast, proteins isolated from these particles showed two new low-Mr immunoreactive peptides (Mr 43 000 and Mr 29 000). No CBP related protein could be detected in polysomal mRNP, although an immunoreactive Mr 43 000 CBP-related protein was present in polysomes. The relevance of the association of different CBP-related polypeptides with cytoplasmic RNP particles and polysomes are discussed.

Advances in cancer therapy with plant based natural products.

Natural Products have long been a fertile source of cure for cancer, which is projected to become the major causes of death in this century. However, there is a continuing need for development of new anticancer drugs, drug combinations and chemotherapy strategies, by methodical and scientific exploration of enormous pool of synthetic, biological and natural products. There are at least 250,000 species of plants out of which more than one thousand plants have been found to possess significant anticancer properties. While many molecules obtained from nature have shown wonders, there are a huge number of molecules that still either remains to be trapped or studied in details by the medicinal chemists. The article reviews many such structures and their related chemistry along with the recent advances in understanding mechanism of action and structure-function relationships of nature derived anti-cancer agents at the molecular, cellular and physiological levels. Taxol, one of the most outstanding agents, has been found beneficial in treatment of refractory ovarian, breast and other cancers. Another prominent molecule includes Podophyllotoxin. Synthetic modification of this molecule led to the development of Etoposide, known to be effective for small cell cancers of the lungs and testes. Camptothecin isolated from Camptotheca acuminata also have been extensively studied. Other important molecules discussed include Vincristine, Vinblastine, Colchicine, Ellipticine and Lepachol along with Flavopiridol, a semi-synthetic analogue of the chromone alkaloid Rohitukine from India, a pyridoindole alkaloid from leaves of Ochrosia species and many more. The review also deals with the lesser-known plants of sub-Himalayan region.

Studies on Escherichia coli as a cause of acute diarrhoea in Calcutta.

The prevalence of different types of diarrhoea-producing Escherichia coli among 240 patients with acute diarrhoea in hospital was investigated. The 25 patients (10.4% of the total) from whose faeces we isolated enteropathogenic E. coli (EPEC) were all less than 5 years old but the 29 (12.1%) from whom we isolated enterotoxigenic E. coli (ETEC) were of various ages, most of them greater than 12 years old. No enteroinvasive E. coli (EIEC) strains were isolated. ETEC strains that produced heat-labile toxin (LT) were encountered more often than those that produced either heat-stable toxin (ST) alone or both LT and ST. The ETEC isolates were distributed among eight different serotypes, the commonest being O148:H28 (38%). Correlations between enterotoxin production, serotype pattern and possession of colonisation factor antigens I and II were observed.

Effect of oral supplementation of vitamin E on the hemolysis and erythrocyte phospholipid-splitting action of cobra and viper venoms.

In the present investigation, it was found that oral supplementation of graded amounts of vitamin E to volunteers increased the alpha-tocopherol content of the erythrocytes and decreased the susceptibility of the latter to the hemolytic action of cobra and viper venoms. Further, exogenous addition of graded amounts of alpha-tocopherol to the red cells, prior to the addition of either venoms, minimizes the venom-induced lysis and erythrocyte phospholipid splitting. It may thus be inferred that vitamin E, a fat-soluble antioxidant, plays an important role in reducing the hemolytic action of cobra and viper venoms.

Primary tuberculosis of the retina.

A case of pseudoglioma diagnosed on histopathology to be retinal tuberculosis is presented with a general review of the literature on ocular tuberculosis. The case is peculiar in that retinal tuberculosis occurred without concomitant involvement of the choroid.

Smooth muscle relaxant properties and vasomotor actions of 2-amino-1-p-nitrophenylpropane-1,3-diol.

Experiments with the guinea pig ileum, trachea, and vas deferens, the rat fundal strip, the rabbit jejunum and aortic strip, and the toad heart indicated that 2-amino-1-p-nitrophenylpropane-1,3-diol, the hydrolytic product of chloramphenicol, inhibited smooth muscles. Its action was direct and not through any mediators. After intravenous administration, the compound produced vasodepression followed by an overshooting rise of blood pressure. Vasodepression was not mediated by adrenergic, cholinergic, or histaminergic mechanisms. Hypertension was a sympathomimetic effect. Muscle relaxant and cardiovascular effects of the compound were similar to those of chloramphenicol, although it had no antibacterial effect.

Structural studies of a specific polysaccharide isolated from non-agglutinable Vibrio.

The purified, specific polysaccharide from Vibrio cholera type NAG, NV 384, O-antigen, 2A, 2B human, contains glucose (5.14%), galactose (4.21%), mannose (64.8%), xylose (3.16%), arabinose (1.98%), fucose (1.50%), mannuronic acid (14.3%), phosphate (0.32%), 2-amino-2-deoxy-D-glucose (2.9%), and 2-amino-2-deoxy-D-galactose (1.0%). Various reactions have shown that the material comprises a phosphoric diester-linked polysaccharide containing mainly ( 1 leads to 2)-linked mannopyranose residues that are highly branched with other sugar residues.

Isolation of a collagen fraction from the body-wall glycoproteins of the leech (Hirudo medicinalis), and characterization of its carbohydrate--amino acid portion.

Fractionation of the leech (Hirudo medicinalis) body-wall glycoproteins yielded a collagen fraction containing only D-glucose and D-galactose as its carbohydrate constituents. Digestion of the collagen with trypsin and pronase, and alkaline degradation of the resulting glycopeptides, gave a product that contained a disaccharide linked to hydroxylysine. Mild, acid hydrolysis of the N-acetylated glycopeptides yielded a disaccharide consisting of a D-glucose and a D-galactose residue. Various chemical and enzymic reactions of the disaccharide, the glycosyloxylysine, and the glycopeptide fraction indicated that the disaccharide is 2-O-alpha-D-glucopyranosyl-D-galactose, and that this is beta-glycosidically linked to O-5 of the hydroxylysine residue in the collagen.

Graded-hydrolysis studies on bael (Aegle marmelos) gum.

Graded hydrolysis of purified bael gum afforded three neutral and two acidic oligosaccharides, together with monosaccharides. These sugars were identified through periodate oxidation, methylation, reduction with lithium aluminum hydride, co-chromatography, and preparation of crystalline derivatives. The neutral oligosaccharides were characterized as 3-0-beta-D-galactopyranosyl-L-arabinose, 5-0-beta-D-galactopyranosyl-L-arabinose, and 3-0-beta-D-galactopyranosyl-D-galactose, and the acidic oligosaccharides as 3-0-(beta-D-galactopyranosyluronic acid)-D-galactose and 3-0-(beta-D-galactopyranosyluronic acid)-3-0-beta-D-galactopyranosyl-D-galactose.

Studies on the partial structure of the O-antigen of Vibrio cholera Ogawa G-2102.

Detailed information was obtained regarding the partial structure of the lipopolysaccharide (LPS), containing glucose, glucuronic acid, 2-amino-2-deoxy-glucose, L-glycero-D-gluco-heptose, and small proportions of L-glycero-D-manno-heptose, mannose, and galactose, isolated from Vibrio cholera Ogawa G-2102. Structures of three oligosaccharides were determined. Results of deamination experiments established the sequence of the linkages between the amino sugar and heptose residues in the O-antigenic polysaccharide.

Structural investigations of the lipopolysaccharide isolated from Vibrio cholera, Inaba 569 B.

On hydrolysis, the purified lipopolysaccharide (LPS) isolated from Vibrio cholera, Inaba 569 B, yielded glucose, mannose, a heptose behaving like D-glycero-L-manno-heptose and one behaving like D-glycero-L-gluco-heptose, 2-amino-2-deoxyglucose, and glucuronic acid in the molar ratios of approximately 9:4:5:1:2:5. Studies on the LPS, the polysaccharide (PS), and carboxyl-reduced LPS showed that the PS has a branched structure, with (1 leads to 2)-linked mannopyranosyl and a heptopyranosyl, and (1 leads to 4)-linked glucopyranosyluronic and 2-amino-2-deoxyglucopyranosyl residues in the interior part of the molecule, and glucopyranosyl and heptopyranosyl residues as nonreducing end-groups.

Studies on the partial structure of the O-antigen of Vibrio cholera, Inaba 569 B.

Five oligosaccharides were isolated in pure state from the lipopolysaccharide of Vibrio cholera, Inaba 569 B, the their structures were elucidated. More-detailed information regarding the partial structure of the lipopolysaccharide, containing glucose, mannose, glucuronic acid, 2-amino-2-deoxyglucose, D-glycero-L-mannoheptose, and D-glycero-L-gluco-heptose, was obtained through Smith degradation, chromium trioxide oxidation, and graded hydrolysis studies of the lipopolysaccharide and its derived products.

Studies on the lanthanum arsenate ion-exchanger: preparation, physicochemical properties and applications.

The cation-exchange behaviour of lanthanum arsenate has been studied. This paper reports the preparation and physicochemical properties of the exchanger. Its analytical utility is compared with that of other arsenate exchangers. Some practical analytical applications are described.

Biochemical composition, lethality and pathophysiology of venom from two cobras-- Naja naja and N. kaouthia.

The cobras Naja naja and N. kaouthia are abundant in eastern and north-eastern India, accounting for maximum snakebite deaths. Here we report on variation in the composition of Naja kaouthia and N. naja venom from eastern India on corresponding differences in the severity of pathogenesis. These two venoms differ in chromatographic elution profile through Sephadex G-50 and enzyme activity, protein and carbohydrate contents associated with each fraction. The presence of greater amounts of basic phospholipase A2, L-amino acid oxidase and low molecular weight membrane active polypeptides in the N. naja venom makes it more toxic than N. kaouthia venom. A commercial polyvalent antivenom raised against N. naja venom inactivates lethality and variety of toxic effects of homologous venom more effectively than N. kaouthia venom.

Flexion osteotomy of the femur for genu recurvatum after poliomyelitis.

We report the results of 21 femoral osteotomies performed in 18 patients for genu recurvatum and flattening of the femoral condyles after poliomyelitis. Before operation the average angle of recurvatum was 31 degrees and all the limbs required bracing. After a mean follow-up of four years there has been partial recurrence in only one case. Nine patients (10 limbs) needed no orthosis and the others had less discomfort and an improved gait. Complete remodelling of the femoral and tibial epiphyses was noted in two of the younger patients.