Mechanical response of melt-spun amorphous filaments

High-speed melt spinning of a cyclo-olefin polymer (COP) and a copolyamide (CoPA) have been performed. Differential scanning calorimetry curves of the resulting monofilaments show that they remain in an amorphous state even after hot drawing. Wide angle x-ray diffraction patterns of undrawn and drawn COP filaments show that although the material remains in an amorphous state, a degree of orientation is induced in the polymer after drawing. The amorphous filaments show an enhanced bending recovery with respect to different semi-crystalline monofilaments commercially available. However, single fiber axial compressive testing indicates that the amorphous filaments exhibit a compressive modulus value which is 50% lower than what is observed for a reference semi-crystalline PET filament. Analysis of the compressive strains applied by the bending recovery test indicates that while the maximum applied strains remain well within the region of elastic deformation of the amorphous materials, the threshold between elastic and plastic deformation is reached for the semi-crystalline materials.

Antibacterial activities and phytochemical analysis of Cassia fistula (Linn.) leaf

Cassia fistula Linn. which belongs to family Leguminosae is a medium-sized tree and its different parts are used in ayurvedic medicine as well as home remedies for common ailments. Sequential extraction was carried out using solvents viz. petroleum ether, chloroform, ethanol, methanol and water from leaf of the plant were investigated for preliminary phytochemical and antibacterial property. Results of the study showed that all the extracts had good inhibitory activity against Gram-positive test organism. Although all five extracts showed promising antibacterial activity against test bacterial species, yet maximum activity was observed in ethanol extract. The minimum inhibitory concentration ranged in between 94 to 1 500 μg/ml. Evaluation of phytochemicals such as alkaloids, flavonoids, carbohydrates, glycosides, protein and amino acids, saponins, and triterpenoids revealed the presence of most of constituents in polar extracts (ethanol, methanol, and aqueous) compared with nonpolar extracts (petroleum ether and chloroform). Furthermore, the ethanol extract was subjected to TLC bioautography and time-kill study against Staphylococcus epidermidis. All the findings exhibit that the leaf extracts have broad-spectrum activity and suggest its possible use in treatment of infectious diseases.

Application of comet assay in the study of DNA damage and recovery in rohu (Labeo rohita) fingerlings after an exposure to phorate, an organophosphate pesticide

Labeo rohita (rohu) fingerlings were exposed to different concentrations (0.001, 0.002 and 0.01 ppm) of phorate, an organophosphate pesticide; samplings were done at 24, 48, 72 and 96 h. The study was carried out to evaluate tissue specific genotoxic effects produced by phorate, on three different tissue systems and to assess DNA repair response in fish. Results of tissue specific DNA damage experiments showed low baseline damage in blood cells followed by gill and liver cells in control individuals whereas more DNA breaks were found in liver followed by gill and blood cells of treated individuals. Concentrations-dependent DNA damage showed a strong, linear and positive relationship (r(2) = >0.7) in all three tissues. Clear time-related increase in DNA damage was observed for all tissues exposed to all concentrations except in liver cells at 0.01 ppm, where the DNA damage declined significantly after 72 h. For the assessment of DNA repair response, fingerlings were first exposed to 0.01 ppm of phorate for 72 h and then transferred to pesticide free water. Tissue chosen for the repair experiment was liver. Samplings were done at 0, 3, 6, 12 and 24 h after the release of 72 h pesticide treated fishes into pesticide free water. Fishes showed a reduction in DNA breaks from 3 h onwards in pesticide free water and at 24 h returned to control level damage. The results indicate that phorate is a potential genotoxicant, comet assay can be used in DNA damage and repair analysis, response to pollutants in multicellular animals is often tissue specific.

Silent neuropathy in leprosy

Twelve patients of silent neuropathy attending the OPD of Skin and VD, VSS Medical College Hospital during 1996-1998 were taken for study. On clinical analysis 5 cases were present as silent neuropathy, 4 cases during MDT and 3 cases after completion of MDT Seventy percent of cases showed good response to systemic steroid.

Ictal deafness--a report of three cases

Though negative phenomena like motor inhibition, blindness or aphasia are described as an ictal manifestation of seizures, ictal deafness has not been reported so far. We observed transient ictal deafness in three cases of partial seizures. One of them had seizure spread to the temporal lobe to produce a complex partial seizure. Two of them have CT-detected lesions in the left temporal/parietal area. The other one had left temporal focus on EEG with a normal imaging study. The mechanism of such ictal negative phenomena is unclear. An epileptic focus around the primary auditory cortex, dampening its receptive ability may manifest as cortical deafness.

Renal involvement in bancroftian filariasis

BACKGROUND

There are anecdotal reports of renal involvement in filariasisbut no systematicstudy has yet been done.

METHODS

Fourteen out of 94 patients attending a filariasis clinic, who had proteinuria, haematuria or chyluria, under-went detailed in-patient investigations including a renal biopsy (9).

RESULTS

Light microscopy of renal biopsy tissue revealed predominantly mesangioproliferative changes in 6 patients with associated inflammatory cell proliferation in 3 and endocapillary cell proliferation in 2 cases. Basement membrane thickening and tubular degeneration were observed in 2 cases each. Under immunofluorescence there were mesangial deposits of IgG alone, orin combination with C3, in 4 patients who showed mesangioproliferative changes under light microscopy. Granular deposits of IgG and C3 along the capillary wall were seen in 1 of the 2 patients who had endocapillary cell proliferation.

CONCLUSIONS

It is suggested that certain patients with filariasishave an immune mediated glomerulopathy.

Immunopathological changes in kidney in Plasmodium falciparum malaria

Fifteen (34.8%) of 43 patients of falciparum malaria screened for urinary abnormalities showed significant proteinuria (greater than 150 mg/24 h), haematuria (greater than 1/HPF) and casts, with or without azotaemia. Light microscopic examination of renal biopsy tissue from 12 patients revealed mesangial and endothelial proliferative change in 8, and acute tubular necrosis in one patient. Immunofluorescence showed IgM alone, or IgG and IgM along with C3, in 7 patients within the mesangium or along the capillary walls. Repeat kidney biopsy after 6 wk in 5 patients revealed no residual pathology indicating the reversible nature of the lesions.

Cryptosporidiosis in children of eastern India

Cryptosporidium infection was found in association with acute diarrhoeal disease in ten patients (13%) of a total of 77 children below the age of 8 years admitted over a period of 1 year to Bhubaneswar Capital Hospital, Orissa state, India. Contrary to another report from South India, there were no asymptomatic cryptosporidium oocyst excretors detected either in the matched control group of 42 children without diarrhoea or in a group of 113 healthy school children investigated. A clustering of seven cases occurred in the months of the rainy season and of three cases in the winter months. Nine out of 63 children (14.3%) below the age of 2 years were infected. Seven of the ten infected children were significantly below their expected weight-for-age, but the mean weight-for-age did not differ from those of the uninfected children. The possible epidemiological factors in the transmission of cryptosporidium are discussed.