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Biomedical subjects

V Bihari

Publications and source records attributed to V Bihari.

At least 19 recordsLinked to original sources

An environmental profile of brick kilns in Lucknow.

Twenty two kilns in Lucknow were studied to identify the environmental hazards posed by the brick kilns and to quantify the environmental degradation which could be attributed to this industry. Study variables comprised SPM and RSPM levels, metal concentrations and total silica content in soil, temperature, humidity and noise levels in the work environment. Information's about the nature and type of kiln, fuel and water sources was also collected. 18.18 per cent of the kilns had moving steel chimneys with less than prescribed height. Approximately 1.89 + 0.87 acre of fertile agricultural land was used for manufacturing of clay brick per kiln, resulting in land degradation decrease in herb density and nutrient disorders in plants/trees in immediate vicinity. SPM level (93.3 mg/m3) was found to be much higher than the prescribed limit. The workers engaged in these kilns were at risk from dust and heat related diseases.

Construction Materials↗

Lead poisoning in Indian silver refiners.

The refining of silver from old silver ornaments, articles and jeweller's waste by smelting these with lead scraps for the fabrication of new jewellery is an important small scale industry in India. The present survey and clinical investigations have shown that 31 out of 50 silver refiners with a mean blood lead level of 32.84+/-1.78 microg/dl (range 20.3-64.9), decrease in blood delta-aminolevulinic acid dehydratase (ALAD) activity and thiamine (as pyruvate) level and an enhanced urinary excretion of ALA as compared to control, were suffering from lead poisoning. Most of these workers have shown anaemia, abdominal colic, blue lining of gum and muscular wasting indicative of lead toxicity. Twenty-four workers with relatively high blood lead levels were equally divided into two groups and given either vitamin B1 (75 mg, once a day) or vitamin C (250 mg. twice a day) for 1 month. The treatment with both the vitamins significantly lowered the blood lead levels and reduced blood thiamine and copper deficiency. In addition, vitamin C was also effective in reversing the inhibition of blood ALAD activity while the effect of vitamin B1 on its activity was marginal. The daily intake of vitamin B1 and vitamin C may prevent the accumulation of lead and reduce its toxic effects particularly in those regularly exposed to lead.

Adolescent↗

Clinical, biochemical and neurobehavioural studies of workers engaged in the manufacture of quinalphos.

59 workers exposed to different chemicals during the manufacture of quinalphos, an organophosphate pesticide (OP) and 17 control subjects were studied. Despite similar blood acetylcholinestarase (AChE) levels in both the exposed and control subjects, a significant number of exposed subjects had altered plantar and ankle reflexes. Higher nervous functions such as memory, learning and vigilance were also found to be affected in these subjects. These findings were attributed to chronic low dose combined exposure to different chemicals used/formed in the manufacture of quinalphos. The study raises the doubt that monitoring of AChE alone among subjects engaged in the manufacture of OP pesticides may not be an adequate safeguard as regards to their health.

Acetylcholinesterase↗

Production of calcium gluconate by fermentation.

Calcium gluconate production by Aspergillus niger was investigated in shake flask, rolling shaker, air-lift reactor and stirred reactor. Growth pattern of the organism and fermentation conditions determined the yield of the product. High calcium gluconate production was achieved in air-lift reactor with pellet form of cell growth at moderate specific growth rate and biomass concentration. In another variation of air-lift reactor, when calcium carbonate was confined to a cellulose membrane, calcium gluconate production was maximum (149 g/L). At higher specific growth rate, obtained in shake flask, despite the formation of cell pellets, product formation was low. Physical separation of particulate calcium carbonate and growing cells favoured product formation. In stirred reactor pulpy mycelial growth was obtained and calcium gluconate production was poor.

Aspergillus niger↗

Hair selenium as a monitoring tool for occupational exposures in relation to clinical profile.

Nineteen workers exposed to low levels of selenium (0.047-0.202 mg/m3 air) along with 15 control subjects were studied for clinical, hematological, radiological, and neurobehavioral variables in relation to selenium concentration in hair. The levels of selenium in the hair of exposed subjects (1.44 +/- 0.37 micrograms/g) were significantly higher than those of control subjects (0.78 +/- 0.18 microgram/g). The levels of selenium in the hair of 22 nonvegetarian subjects were found to be significantly higher as compared to 12 vegetarian subjects. Complaints of weakness and/or fatigue were found to be more prevalent in the exposed subjects. The study holds promise that hair selenium may be used as a monitoring tool for low-level occupational exposure to selenium.

Adult↗

Production of L-phenylacetylcarbinol by free and immobilized yeast cells.

Production of L-phenylacetylcarbinol (L-PAC) through biotransformation of benzaldehyde by free and immobilized cells of the yeast Saccharomyces cerevisiae has been attempted. L-PAC production was found to be maximum (0.4 microliter/ml) when anaerobically grown free cells were used as biocatalyst during aerobic biotransformation for two hours with magnetically stirred bioreactor. Growth under oxygen limited conditions led to accumulation of higher amount of pyruvate decarboxylase enzyme and co-substrate, pyruvate, resulting in higher L-PAC formation. L-PAC yield was low when biotransformations were carried out anaerobically either for aerobically or anaerobically grown free cells. Free cells were found to be more efficient biocatalyst for L-PAC production, as compared with the immobilized cells, with the investigated benzaldehyde concentration (0.3% v/v) and cell density (17.5% w/v). The study has explored and indicated the possibility of optimizing the yield of L-PAC by growing the yeast cells under oxygen limited condition for suitable aerobic mode of benzaldehyde biotransformation.

Acetone↗

Generalized hair loss and selenium exposure.

The manufacture and maintenance of drums used in photocopy machines involves use of a selenium alloy. A worker employed in this type of job for 6 mo presented with alopecia aereta which later deteriorated to alopecia universalis. As selenium intoxication is known to present with a similar clinical picture, selenium levels in blood and nails of this subject were estimated and compared with those found in other workers. We report a case of alopecia universalis due to occupational selenium intoxication.

Adult↗

Organochlorine pesticide exposure and thyroid function: a study in human subjects.

We examined the serum levels of thyroxine and thyroid stimulating hormone in 103 rural subjects with respect to blood levels of organochlorine pesticide and occupation. We found that 24.3% of study subjects had depleted thyroxine levels in association with significantly lower organochlorine pesticide residues in blood. Sex, nutritional status, thyromegaly, or handling of pesticides in the course of work were not found to be factors contributing to depleted thyroxine levels.

Adult↗

High-density cultivation of sporeformers.

Sporeformers are sources of a large number of industrially important biological products including enzymes, antibiotics, and bioinsecticides. Cultivation of these microorganisms to high cell densities offers potential for enhancing the rates of formation as well as the concentration of the desired products in the fermentation broths in bioreactors. With this objective, investigations have been carried out involving fed-batch cultivation of Bacillus thuringiensis, which is known to produce an insecticidal crystal protein during sporulation. With appropriate management of aeration and nutrient supply, it was possible to grow the cells to > 50 g DW/l density. Nevertheless, the achievement of high cell density did not enhance the formation of crystal protein in the same proportion as the cell concentration. Further examination of this system suggested a complex interplay of energetic requirements for protein turnover during sporulation. Energy reserve material, poly-beta-hydroxybutyric acid, appeared to be linked to formation of spores and crystal protein during the sporulation phase.

Bacillus thuringiensis↗

Differentiation of malignant and degenerative bone lesions using dexamethasone interventional 3- and 24-hour bone scintigraphy.

Seventy-seven adult patients with suspected skeletal metastases were divided into two groups. In group A (n = 30), following intravenous administration of 20 mCi (740 MBq) of technetium-99m methylene diphosphonate (99mTc-MDP), 3- and 24-h scintigraphy of bone lesions was performed. The 24/3 h lesion to bone background radiouptake ratio (RUR) was calculated for each lesion. In group B (n = 47), the same procedure was followed with dexamethasone intervention (10 mg in 24 h) following the 3-h acquisition. In group A, after determination of the critical point, malignant and degenerative bone lesions could be separated with a sensitivity, specificity and accuracy of 0.76, 0.72 and 0.73, respectively. The mean RUR of the malignant lesions was 1.20 +/- 0.23, and that of the benign lesions, 0.95 +/- 0.15. In group B cases, significantly increased sensitivity, specificity and accuracy of 0.87, 0.94 and 0.92, respectively, were found (P < 0.001). The mean RUR of the malignant lesions was 1.48 +/- 0.34, and that of degenerative lesions, 0.88 +/- 0.19. Dexamethasone interventional bone scintigraphy seems to be a new cost-effective method for differentiating malignant from degenerative bone lesions using the RUR.

Bone Diseases↗

A study of extra-auditory effects of noise.

Paper mill workers (106) exposed to noise ranging from 80 to 96 dBA were assessed for alteration in clinical status. Neurobehavioral functions were examined with the help of a questionnaire. The study did not reveal any changes attributable to noise in subjects exposed to 86-90 dBA and > 90 DBA noise in course of their occupations.

Adult↗

Clinical studies in workers engaged in maintenance of watermark moulds in a paper mill.

Thirty subjects engaged in maintenance and repair of moulds used for producing watermarks on paper were studied, along with 27 control subjects from the same paper mill. The workers were simultaneously exposed to copper, chromium, zinc, xylol, and fumes of sulphuric acid in the course of their work. The study subjects were investigated for clinical, occupational, radiological haematological and psychological details. The aforementioned combined exposure was found to be responsible for a high prevalence of symptoms pertaining to the respiratory system and higher nervous functions. Breathlessness (26.7%), expectoration (10.0%) and emphysema (10.0%) were significantly higher among the exposed subjects. The exposed subjects also showed lowered visuomotor coordination and delayed reaction to light and sound stimuli.

Adult↗

Clinical studies of employees in a sheet-forming process at a paper mill.

Formaldehyde resins are used to improve the wet strength of paper. During the sheet-forming process of paper manufacture, formaldehyde fumes are liberated. Twenty-two male subjects having such exposures in a paper mill and 27 unexposed subjects were clinically evaluated to determine the effect of low level formaldehyde exposure in a tropical country. The workers were exposed to 0.03 mg formaldehyde/m3 air as an 8-h TWA. Formic acid excretion in urine was 37.2 +/- 18.9 and 20.3 +/- 4.2 ug/L among the exposed and the unexposed subjects, respectively. Significantly more respiratory problems (31.8%) were observed among the exposed subjects as compared to controls. Complaints pertaining to gastrointestinal, musculoskeletal and cardiovascular systems were also more frequent in exposed subjects. In spite of formaldehyde concentrations being well within the prescribed ACGIH limits of 1 ppm, the high rates of sickness emphasise the need for detailed studies on formaldehyde-exposed subjects in tropical countries.

Adult↗

Occupational morbidity among children employed in brassware industry.

Fifty seven male children between ages of 10-16 years engaged in the brassware industry at Moradabad in Northern India were studied for occupational morbidity. The finding were compared with those obtained in the children (n = 29) engaged in other ancillary units which did not involve exposure to the metal fumes and dust in their work environment. The study showed a high prevalence of respiratory morbidity in the children engaged in the main units in comparison to those employed in the ancillary units (40.3 vs 27.6%; p less than 0.05). This was associated with significantly higher prevalence of pulmonary impairment in the former group (21.0%) particularly demonstrating restrictive ventilatory abnormality (10.5%) followed by bronchial obstruction (7.0%). The high respiratory morbidity may be attributed to chronic exposure to the fumes and dust of the metals such as nickel, chromium and cadmium. The children employed in the ancillary as well as in the main units showed high prevalences of musculo-skeletal disorders (27.6 and 22.8%) which may be caused by sustained faulty posture adopted during work and physical stress.

Adolescent↗