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Biomedical subjects

C M Reddy

Publications and source records attributed to C M Reddy.

At least 19 recordsLinked to original sources
PubMed2006

Climatically driven emissions of hydrocarbons from marine sediments during deglaciation.

Marine hydrocarbon seepage emits oil and gas, including methane ( approximately 30 Tg of CH(4) per year), to the ocean and atmosphere. Sediments from the California margin contain preserved tar, primarily formed through hydrocarbon weathering at the sea surface. We present a record of variation in the abundance of tar in sediments for the past 32,000 years, providing evidence for increases in hydrocarbon emissions before and during Termination IA [16,000 years ago (16 ka) to 14 ka] and again over Termination IB (11-10 ka). Our study provides direct evidence for increased hydrocarbon seepage associated with deglacial warming through tar abundance in marine sediments, independent of previous geochemical proxies. Climate-sensitive gas hydrates may modulate thermogenic hydrocarbon seepage during deglaciation.

Journal Article↗
PubMed2005

Determination of HBCD, PBDEs and MeO-BDEs in California sea lions (Zalophus californianus) stranded between 1993 and 2003.

Blubber samples from male California sea lions (Zalphophus californianus) stranded between 1993 and 2003 were analyzed for 27 polybrominated diphenyl ether (PBDE) congeners, three isomers of hexabromocyclododecane (HBCD) and 14 methoxylated polybrominated diphenyl ether (MeO-BDE) congeners. Total PBDEs ranged from 450 ng/g to 4740 ng/g wet mass and total HBCD ranged from < 0.3 ng/g to 12 ng/g wet mass. The concentration of HBCD increased from 0.7 ng/g to12.0 ng/g wet mass in sea lion blubber between 1993 and 2003. However, no significant temporal trend was observed for any of the other brominated compounds over this 10 year period. Only one of the 14 MeO-BDE congeners was detected in the blubber samples, 6-methoxy-2,2',4,4'-tetrabromodiphenyl ether (6-MeO-BDE 47), and concentrations ranged from < 0.2 ng/g to 12 ng/g wet mass. A bromo-, chloro-heterocyclic compound, 1,1'-dimethyl-tetrabromo-dichloro-2,2'-bipyrrole (DBP-Br4Cl2), previously reported in marine species along the Pacific coast, was also identified in the sea lion blubber. DBP-Br4Cl2 ranged from 44 ng/g wet mass to 660 ng/g wet mass and was present at concentrations rivaling the dominant PBDE congener, BDE 47 (2,2',4,4'-tetrabromodiphenyl ether). Concentrations of DBP-Br4Cl2 were positively correlated with 6-MeO-BDE 47 (r = 0.7; p < 0.05). Both of these compounds have been identified in marine algae and sponges, and studies suggest they are both produced from natural sources. This study demonstrates that brominated compounds from both anthropogenic and biogenic sources can accumulate to similar levels in marine mammals. In addition, HBCD concentrations appear to be increasing in California sea lion populations, whereas PBDE concentrations, between 1993 and 2003, were highly variable.

Adipose Tissue↗
PubMed2001

The absence and application of stable carbon isotopic fractionation during the reductive dechlorination of polychlorinated biphenyls.

A bacterial enrichment culture (specific to doubly flanked chlorine removal) reductively dechlorinated 2,3,4,5-tetrachlorobiphenyl (2,3,4,5-CB) to 2,3,5-trichlorobiphenyl (2,3,5-CB) in aqueous media. Approximately 90% conversion to 2,3,5-CB occurred after 90 days, with no other products formed. The delta13C values of 2,3,4,5-CB and 2,3,5-CB were relatively constant over the course of the reaction, indicating a very small or no isotope effect. In addition, compound-specific delta13C analysis performed for every congener in three different lots of Aroclor 1268 showed an intrinsic isotopic trend of decreasing 13C abundance with increasing chlorine content, similar to observations in other commercial mixtures of polychlorinated biphenyls (PCBs). The results of this laboratory study suggest that microbial reductive dechlorination of PCBs in contaminated sediments will create congeners with more depleted delta13C values than native PCBs of similar chlorination. Such information may provide additional evidence for the occurrence of this process and aid in further understanding the biogeochemistry of these compounds.

Bacteria↗
PubMed2001

The North Cape oil spill: hydrocarbons in Rhode Island coastal waters and Point Judith Pond.

On 19 January 1996, the North Cape oil barge ran aground near Moonstone Beach, RI, and spilled over 2700 metric tons of No. 2 fuel oil during a severe winter storm. High winds and rough seas drove the oil into the water column, and the oil spread throughout Block Island Sound and into several coastal salt ponds. Over 50 water samples were collected from Point Judith Pond (PJP) and the southern coast of Rhode Island for four months after the spill and analyzed for polycyclic aromatic hydrocarbons (PAHs) and total petroleum hydrocarbons (TPHs). These analyses revealed that at least 60 km2 of coastal waters were impacted from the spill. Maximum concentrations of sigmaPAHs and TPHs were 115 and 3940 microg l(-1), respectively. The percentage of sigmaPAHs relative to the TPHs for all samples varied from 0.2 to 43%, showing that there was no clear relationship between sigmaPAHs and TPHs for the whole dataset and likely resulting from spatial and temporal partitioning over the course of the spill. However, within the dataset, there were stronger correlations for distinct samples collected at similar locations and times. In PJP, water column concentrations of individual PAHs decreased at rates of 0.08-0.24 day(-1) and lower-molecular weight PAHs were removed faster than higher-molecular weight PAHs.

Environmental Monitoring↗
PubMed2000

Selective inhibition of cyclooxygenase-2 by C-phycocyanin, a biliprotein from Spirulina platensis.

We report data from two related assay systems (isolated enzyme assays and whole blood assays) that C-phycocyanin a biliprotein from Spirulina platensis is a selective inhibitor of cyclooxygenase-2 (COX-2) with a very low IC(50) COX-2/IC(50) COX-1 ratio (0.04). The extent of inhibition depends on the period of preincubation of phycocyanin with COX-2, but without any effect on the period of preincubation with COX-1. The IC(50) value obtained for the inhibition of COX-2 by phycocyanin is much lower (180 nM) as compared to those of celecoxib (255 nM) and rofecoxib (401 nM), the well-known selective COX-2 inhibitors. In the human whole blood assay, phycocyanin very efficiently inhibited COX-2 with an IC(50) value of 80 nM. Reduced phycocyanin and phycocyanobilin, the chromophore of phycocyanin are poor inhibitors of COX-2 without COX-2 selectivity. This suggests that apoprotein in phycocyanin plays a key role in the selective inhibition of COX-2. The present study points out that the hepatoprotective, anti-inflammatory, and anti-arthritic properties of phycocyanin reported in the literature may be due, in part, to its selective COX-2 inhibitory property, although its ability to efficiently scavenge free radicals and effectively inhibit lipid peroxidation may also be involved.

Animals↗
PubMed1999

Field evaluation of Spicbiomoss, a biolarvicidal formulation of Bacillus sphaericus against immatures of Culex quinquefasciatus & Anopheles species.

Spicbiomoss, an aqueous suspension formulation of Bacillus sphaericus was evaluated for its efficacy against immatures of Culex quinquefasciatus at the application rate of 120 l/ha in cement tanks, cesspits and drains in Pondicherry and in drains in Kochi, Kerala. The formulation was also tested against anophelines (Anopheles fluviatilis and An. culicifacies) breeding in stream pools in Malkangiri district, Orissa. In cement tanks and cesspits more than 80 per cent reduction in immature density was observed for a period of 6-13 days (mean 9.8 +/- 1.25 days) and 3-8 days (mean 5.2 +/- 0.7 days) respectively. The same level of reduction was found to last for 1-4 days (mean 2.2 +/- 0.52 days) in drains in Pondicherry and 2-9 days (mean 4.8 +/- 1.17 days) in Kochi. In bunded stream pools 40-79 per cent reduction in immature density of Anopheles was obtained for an average period of 1-7 (mean 3.83 +/- 0.98) days. There was no improvement in the efficacy of the formulation against anophelines even at the higher application rate (240 l/ha). Thus, Spicbiomoss can be used against Cx. quinquefasciatus in an integrated vector management programme.

Animals↗
PubMed1997

Effect of benzene extract of Hibiscus rosa sinensis on the estrous cycle and ovarian activity in albino mice.

The benzene extract of Hibiscus rosa sinensis flowers was administered intraperitoneally at the dose levels of 125 and 250 mg/kg body weight to adult mice and resulted in an irregular estrous cycle with prolonged estrus and metestrus. An increase in the atretic follicles and the absence of corpora lutea indicate the antiovulatory effect of the extract. The extract also showed estrogenic activity in immature mice by early opening of the vagina, premature cornification of the vaginal epithelium and an increase in uterine weight. Therefore the antiovulatory effect may be due to an imbalance in the hormonal environment, as there may be an increase in the endogenous secretion of estrogen by atretic follicles, and also to the estrogenicity of the flower extract.

Animals↗
PubMed1997

Antispermatogenic and androgenic activities of various extracts of Hibiscus rosa sinesis in albino mice.

The benzene chloroform and alcoholic extracts of the flowers of H.r.sinensis were administered (i.p.) at two different dose levels of 125 and 250 mg/kg body weight to adult male albino mice for 20 days. The results have shown decrease in the spermatogenic elements of testis and epididymal sperm count. High content of testicular cholesterol may be due to lowered androgen synthesis. The increase in the weight of accessory reproductive organs indicates the androgenicity of the plant extract itself, which is proved in the present study by testing the benzene extract in immature mice.

Androgen Antagonists↗
PubMed1996

Brackish water mosquito problem of Vypeen Island, Cochin, Kerala.

A preliminary study has shown that the marshy terrain and brackish water bodies associated with mangrove forests contributed profuse breeding of mosquitos in Vypeen island, causing a severe menace to the island population. A total of 14 species belonging to four genera viz, Aedes, Anopheles, Armigeres and Culex was recorded from different habitats. Culex sitiens was found to be the predominant mosquito in all the perennial breeding habitats. The extent of different habitats in the production of mosquitos, and its possible abatement, using environmental and/or biocontrol methods are discussed.

Animals↗
PubMed1992

Sickle cell disease with complicated influenza B virus infection.

The Committee on Infectious Diseases of the American Academy of Pediatrics, and the Advisory Committee on Immunization Practices of the Center for Disease Control for many years have recommended the routine use of influenza vaccine in various hemoglobinopathies including sickle cell disease. This recommendation, however, has not been included in the patient care protocols of the Comprehensive Sickle Cell Centers program of NIHLB. Most clinicians have not used yearly influenza vaccine for their patients with sickle cell disease. This article reports a case of a 5-year-old boy with sickle cell disease who had not received influenza vaccine. He developed pneumonitis and acute myositis during a serologically confirmed influenza B virus infection. The incapacitating and protracted course of his illness presented diagnostic and management problems. His case strongly supports the recommendation of the two infectious disease committees.

Antibodies, Viral↗
PubMed1991

Evaluation of Bacillus sphaericus formulations against the vector of bancroftian filariasis.

Three different formulations of Bacillus sphaericus viz, Spherimos, Vectobac and Spherifix, were evaluated for their efficacy and residual activity against Culex quinquefasciatus breeding in polluted disused wells. Spherimos, a flowable concentrate formulation, exerted 96-100% control when treated at the dosage of 10 l/ha for 17 days, whereas the effective residual activity lasted up to 67 days at 15 l/ha. In the case of Vectolex, a granular formulation, the residual activity lasted up to 56 days with the dosage of 30 l/ha and up to 66-77 days with higher dosages of 45 and 60 l/ha. The residual activity of Spherifix, a floating controlled release formulation, lasted up to 67 days with a dosage of 10 kg/ha.

Animals↗
PubMed1983

Diagnostic use of cerebrospinal fluid lactic acid levels in meningitis.

Analysis of cerebrospinal fluid lactic acid levels in 62 patients suspected of having meningitis was performed. Lactic acid was measured enzymatically using lactic acid dehydrogenase with the liberation of NADH. In a control (no meningitis) group, 46 children had a mean cerebrospinal fluid lactic acid level of 14.7 +/- 2.2 mg/dl; 3 with febrile seizure had a mean lactic acid level of 33.5 +/- 0.98 mg/dl. In 9 cases of bacterial meningitis, the mean lactic acid level was 54.8 +/- 16.8 mg/dl. In 3 patients of aseptic meningitis, the mean lactic acid level was 34.5 +/- 1.0 mg/dl. Serial lactate determination was done in three patients and they were well correlated with the clinical response and other cerebrospinal fluid findings. These data suggest that the determination of cerebrospinal fluid lactic acid may be of diagnostic value in differentiating between bacterial and aseptic meningitis.

Adolescent↗
PubMed1980

Endocrine disorders associated with mental retardation.

Endocrine disorders associated with mental retardation are described in relation to clinical characteristics, pathogenesis, diagnostic procedures, and treatment. Some endocrine disorders, particularly hypothyroidism, nephrogenic-diabetes insipidus, and hypoglycemic conditions, are frequently associated with mental retardation. Early diagnosis and prompt and proper management reduce mortality and the incidence of mental retardation associated with endocrine disorders.

Child↗
PubMed1979

Propylthiouracil and hepatitis: a case report.

A 10-year-old girl initially presented with clinical features and thyroid function tests consistent with hyperthyroidism. She was treated with propylthiouracil, 100 mg, three times a day. She developed jaundice and hepatitis following treatment with propylthiouracil for 40 days. Clinical features of hepatitis improved after the discontinuation of propylthiouracil and she became euthyroid. At this time, an immunofluorescent technique revealed antibodies consistent with autoimmune thyroiditis. From this report, it appears that hepatitis is one of the infrequent complications of treatment with propylthiouracil and transient hyperthyroidism may be associated with autoimmune thyroiditis.

Chemical and Drug Induced Liver Injury↗