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The present work reports the larvicidal potential of microbially synthesised silver nanoparticles (AgNPs) by using an actinobacterium, Streptomyces sp. M25 isolated from Western Ghats, Tamil Nadu, India. The biomass of Streptomyces sp. was exposed to 1 mM silver nitrate (AgNO3) solution. The synthesis of AgNPs was confirmed by visual inspection followed by instrumental analysis such as UV-vis spectroscopy, fourier transform infrared spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray spectroscopy, scanning electron microscopy, atomic force microscopy and transmission electron microscopy (TEM) with selected area electron diffraction. Based on the TEM and XRD analysis, the average size of the AgNPs was determined to be 10-35 nm. The biosynthesised AgNPs exhibited significant larvicidal activity against malarial vector, Anopheles subpictus (LC50 51.34 mg/L and χ (2) value of 8.228), filarial vector, Culex quinquefasciatus (LC50 48.98 mg/L and χ (2) value of 14.307) and dengue vector, Aedes aegypti (LC50 60.23 mg/L and χ (2) value of 4.042), respectively. Similarly, AgNO3 had larvicidal activity against malarial vector, A. subpictus (LC50 42.544 mg/L and χ (2) value of 2.561), filarial vector, C. quinquefasciatus (LC50 44.922 mg/L and χ (2) value of 1.693) and dengue vector, A. aegypti (LC50 39.664 mg/L and χ (2) value of 5.724), respectively. The current study is a rapid, cost effective, eco-friendly and single step approach. The Streptomyces sp. M25 is a newly added source for the synthesis of AgNPs with improved larvicidal activity.

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The innovative design and synthesis of nanofiber based hydro-philic/phobic membranes with a thin hydro-phobic nanofiber layer on the top and a thin hydrophilic nanofiber layer on the bottom of the conventional casted micro-porous layer which opens up a solution for membrane pore wetting and improves the pure water flux in membrane distillation.

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STUDY DESIGN: A 15-year clinical follow-up of tuberculous lesions of the lumbosacral region. OBJECTIVES: To verify the hypothesis that the lumbar lordosis and the specific biomechanics of the lumbosacral region influence and alter the healing pattern and progress of the disease when compared with their effects in other regions of the spine. SUMMARY OF BACKGROUND DATA: An estimated 2 million or more patients have active spinal tuberculosis, and the global incidence of the disease is increasing. The involvement of the lower lumbar region and the lumbosacral junction is relatively rare, with few reports in English literature. METHODS: Of a total of 304 patients forming a part of a controlled clinical trial comparing two forms of therapy in spinal tuberculosis, 53 patients had involvement of L3 and below. The following data were studied in these patients: age at start of treatment, number of vertebra involved, vertebral body loss, progress of the angle of kyphosis, and anterior and posterior growth of the involved segment during a period of 15 years. Student's t test for independent samples was used for statistical analysis. RESULTS: The fourth lumbar vertebra was the most common vertebral segment involved, and the lumbosacral junction was affected in 12 patients. The average pretreatment kyphosis was 6.4 degrees and increased to 10.2 degrees at the end of 15 years. The average kyphotio angle per vertebral body loss was 4.9 degrees, far less than in the dorsolumbar region in which kyphotic angles of 27-30 degrees have been reported. Children younger than 10 years old differed in clinical appearance and progress compared with those older than 17 years. They not only showed more extensive involvement but also had more deformity with the same vertebral loss. Twelve patients less than 10 years old had an average involvement of 3.1 vertebral bodies and an average vertebral loss of 2.2 bodies. In comparison, the average number of vertebrae involved was 1.9 (P < 0.01) and the vertebral body loss was only 0.87 (P < 0.01) in patients older than 17 years. Also, the average kyphosis was 6.4 degrees compared with only 4.2 degrees (P < 0.01) in adults. In patients older than 17 years, there was no change after 2 years, by which time the collapse was complete. Four of 12 patients less than 10 years old, showed progressive kyphosis caused by continued growth of posterior parts of the body (i.e., sequestrated hemivertebrae). CONCLUSIONS: In tuberculosis of the lumbosacral region, the development of kyphosis is minimal in patients older than 17 years, when growth has already stopped, and deformity is expressed more as foreshortening of the trunk. Children younger than 10 years old have more severe involvement with increased tendency toward greater kyphosis. They are also prone to progressive deformity through the years when the anterior growth plates are destroyed. Surgery is indicated in this group to prevent greater deformity.

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OBJECTIVE: To assess the efficacy of 9-month short-course chemotherapy (SCC) and to study the pattern of neurological recovery in patients with Pott's paraplegia. DESIGN: Patients with recent onset of spastic paraplegia due to clinically and radiologically active spinal tuberculosis involving vertebral bodies of level D4-L1 were treated with streptomycin, rifampicin, isoniazid and ethambutol daily for the first 2 months, followed by rifampicin plus isoniazid twice weekly for the next 7 months. The study was conducted in 2 phases. In the first phase 10 patients were admitted to the open trial where all patients had undergone modified Hong Kong surgery in addition to chemotherapy. In the next phase 23 patients enrolled in the study were randomly allocated to receive either chemotherapy alone or surgery plus chemotherapy. All the patients were followed for 5 years from the start of treatment. A scoring system was devised to predict neurological recovery. RESULTS: In all, 33 patients were admitted and treated with SCC. Thirteen patients were allocated to the chemotherapy (CHEM) regimen; of these 3 patients had to be operated upon for clinical deterioration; the remaining 20 had surgery plus chemotherapy; 4 were excluded for various reasons, leaving 29 patients in the analysis. None relapsed requiring treatment. CONCLUSION: A combination of surgery (when indicated) and SCC of 9 months' duration is effective in the treatment of Pott's paraplegia. All patients had neurological recovery by the end of 9 months; 8 recovered with chemotherapy alone. Complete motor recovery was seen in 62% by the 3rd month and 90% by the 6th month.

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In Clostridium thermoaceticum, the synthesis of acetyl-CoA from methyl tetrahydrofolate occurs via a series of enzymatic reactions involving methyl transferase, corrinoid/Fe-S protein (corrinoid), carbon monoxide dehydrogenase (CODH) and ferredoxin. We have investigated the possibility of one or more of these proteins existing as multi-enzyme complexes in vivo with higher catalytic activity. A protein complex consisting of CODH and corrinoid was isolated from the cell-free extracts of Clostridium thermoaceticum. The acetyl-CoA synthesis was found to be approximately 1.8-fold higher with the complex than that observed with the isolated protein components. HPLC gel filtration analyses of the native and DTE reduced complex suggested that the CODH:corrinoid complex is held together primarily by an inter disulfide bond. By differential labeling of thiols with [14C]N-ethylmaleimide it was found that Cys-506 of the alpha subunit of CODH was involved in the disulfide linkage with the corrinoid of the complex.

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The psychological features of spinal cord injured (SCI) patients involved in the Madras Paraplegia Project are described. Three hundred and twenty-eight patients were studied. Based on personality tests, 11% were extroverts, 14% were introverts and 76% were neither extroverts nor introverts. Twenty-four percent of the subjects were neurotic, 11% had a depressive illness, and 26% had pathological anxiety. The study has highlighted the psychological status of SCI patients, and the usefulness of a psychiatric team in the multidisciplinary care of such patients. This is probably the first large psychological study of SCI patients from a developing country.

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Acetogenic bacteria, as determined with Clostridium thermoaceticum, synthesize acetate by the acetyl-CoA pathway which involves the reduction of CO2 to a methyl group and then combination of the methyl with CoA and a carbonyl group formed from CO or CO2 (Wood, H.G., Ragsdale, S.W., and Pezacka, E. (1986) Trends Biochem. Sci. 11, 14-18). Carbon monoxide dehydrogenase (CODH), the key enzyme in this pathway not only catalyzes the oxidation of CO to CO2 but also the final step, the synthesis of acetyl-CoA from a methyl group, CO, and CoA. Previously, it has been shown that ferredoxin can stimulate exchange of CO with CH3 14COSCoA (Ragsdale, S.W., and Wood, H.G. (1985) J. Biol. Chem. 260, 3970-3977). In the present study, it has been observed that ferredoxin and CODH can form an electrostatically stabilized complex. In order to identify the ferredoxin binding region on CODH, the ferredoxin and CODH were cross-linked by using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide. The cross-linked CODH-ferredoxin adduct was enzymatically as active as the uncross-linked complex. The native CODH and cross-linked CODH-ferredoxin complex were subjected to cyanogen bromide cleavage. By comparison of the high-performance liquid chromatography peptide profiles, it was observed that the mobility of at least one peptide is altered in the CODH-ferredoxin cross-linked complex. The peptide was identified with residues 229-239 of the alpha-subunit of CODH.

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CO dehydrogenase/acetyl-coenzyme A synthase (CODH) is the central enzyme in the pathway of acetyl-coenzyme A biosynthesis in Clostridium thermoaceticum. It catalyzes the interconversion of CO and CO2 and the synthesis of acetyl-coenzyme A from the methylated corrinoid/iron sulfur protein, CO, and coenzyme A. It is a nickel-iron-sulfur protein and contains two subunits in the form (alpha beta)3. Reported here is the cloning and sequencing of the genes for both subunits of CODH. The gene for the alpha subunit codes for a protein with 729 amino acids and a molecular weight of 81,730, and the beta gene for a protein with 674 amino acids and a molecular weight of 72,928. The alpha subunit follows the beta subunit by 23 bases and the genes for both subunits are preceded by a sequence which is similar to the Shine-Dalgarno sequence of Escherichia coli. No significant amino acid sequence homology has been found to any known sequence. Labeling CODH with 2,4-dinitrophenylsulfenyl chloride and isolating labeled peptide fragments demonstrated that a tryptophan, residue 418 of the alpha subunit, is protected by coenzyme A and thus may be considered a potential part of the coenzyme A site.

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Carbon monoxide dehydrogenase (CODH) is the key enzyme of autotrophic growth with CO or CO2 and H2 by the acetyl-CoA pathway. The enzyme from Clostridium thermoaceticum catalyzes the formation of acetyl-CoA from the methyl, carbonyl, and CoA groups and has separate binding sites for these moieties. In this study, we have determined the role of arginine residues in binding of CoA by CODH. Phenylglyoxal, an arginine-specific reagent, inactivated CODH, and CoA afforded about 80-85% protection against this inactivation. The other ligands, such as the carbonyl and the methyl groups, gave no protection. By circular dichroism, it was shown that the loss of activity is not due to extensive structural changes in CODH. Earlier, we showed that tryptophan residues are located at the CoA binding site of CODH [Shanmugasundaram, T., Kumar, G. K., & Wood, H. G. (1988) Biochemistry 27, 6499-6503]. A comparison of the fluorescence spectra of the native and phenylglyoxal-modified enzymes indicates that the reactive arginine residues appear to be located close to fluorescing tryptophans. Fluorescence spectral studies with CoA analogues or its components showed that CoA interacts with the tryptophan(s) of CODH through its adenine moiety. In addition, evidence is presented that the arginines interact with the pyrophosphate moiety of CoA.

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Carbon monoxide dehydrogenase (CODH) from Clostridium thermoaceticum plays a central role in the newly discovered acetyl-CoA pathway [Wood, H.G., Ragsdale, S.W., & Pezacka, E. (1986) FEMS Microbiol. Rev. 39, 345-362]. The enzyme catalyzes the formation of acetyl-CoA from methyl, carbonyl, and CoA groups, and it has specific binding sites for these moieties. In this study, we have determined the role of tryptophans at these subsites. N-Bromosuccinimide (NBS) oxidation of the exposed and reactive tryptophans (5 out of a total of approximately 20) of CODH at pH 5.5 results in the partial inactivation of the exchange reaction (approximately 50%) involving carbon monoxide and the carbonyl group of the acetyl-CoA. Also, about 70% of the acetyl-CoA synthesis was abolished as a result of NBS modification. The presence of CoA (10 microM) produced complete protection against the partial inhibition of the exchange activity and the overall synthesis of acetyl-CoA caused by NBS. Additionally, none of the exposed tryptophans of CODH was modified in the presence of CoA. Ligands such as the methyl or the carbonyl groups did not afford protection against these inactivations or the modification of the exposed tryptophans. A significant fraction of the accessible fluorescence of CODH was shielded in the presence of CoA against acrylamide quenching. On the basis of these observations, it appears that certain tryptophans are involved at or near the CoA binding site of CODH.

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Carbon monoxide dehydrogenase (CODH) plays a key role in acetate synthesis by the acetogenic bacterium, Clostridium thermoaceticum. Acetobacterium woodii, like C. thermoaceticum contains high levels of CODH. In this work we show that crude extracts of A. woodii synthesize acetate from methyl tetrahydrofolate or methyl iodide, carbon monoxide and coenzyme A (CoA). The purified CODH from A. woodii catalyzes an exchange reaction between CO and the carbonyl group of acetyl-CoA even faster than the C. thermoaceticum enzyme, indicating the CODH of A. woodii, like that of C. thermoaceticum is an acetyl-CoA synthetase. Fluorescence and EPR studies further support this postulate by demonstrating that CODH binds CoA near the CO binding site involving a tryptophan residue. The UV absorption spectra and the amino acid compositions of A. woodii and C. thermoaceticum CODHs are very similar. Evidence is presented using purified enzymes from A. woodii that the synthesis of acetyl-CoA occurs by a pathway similar to that utilized by C. thermoaceticum.

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The aims, objectives and results of the Madras Paraplegia Project at the Government General Hospital, Madras is presented. Eight hundred and forty four Spinal Cord Injury (SCI) patients have been treated in 8 years and 4 months. The Madras Model offers an alternative strategy for the total care of SCI patients. The merits and drawbacks are highlighted. The results to date commend replication of the model in areas of the world where the services for SCI Care are meagre or non-existent.

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The cases of ninety patients who had tuberculous lesions in the thoracic and thoracolumbar spine were studied. A comparison of the angles of the gibbus deformity at onset and six years later showed statistically significant differences between the patients who underwent treatment by radical surgery and those who underwent treatment by one of two non-surgical regimens. Analysis of the amount of the initial loss of vertebral body and of the final angle of the gibbus deformity at six years showed a correlation coefficient of 0.83. Using the formula y = a + bx, the final angle of the gibbus deformity was predictable with 90 per cent accuracy in the patients who were not treated surgically. The ability to predict the final angle of the gibbus deformity allows the surgeon to select the patients who will require radical resection and bone-grafting to prevent a severe kyphosis.

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A personal series of 169 cases of post-injection fibrosis of skeletal muscle consisting of 78 cases of deltoid fibrosis, 84 cases of quadriceps fibrosis, 6 cases of gluteal fibrosis and one case of triceps fibrosis are presented. Discussion includes an extensive review of literature. A plea is made for pevention of the condition.

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Biopsy specimens from 93 patients with mycetoma were examined histologically; Streptomyces pelletieri was found in 12 cases. In addition, two cases of actinomycetoma pedis in which S pelletieri has been isolated in culture are described. In both, the characteristic red granules were seen.

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