Biomedical subjects

S Bag

Publications and source records attributed to S Bag.

5 recordsLinked to original sources

PubMed2006

[A comparison of the gene expression patterns of human chondrocytes and chondrogen differentiated mesenchymal stem cells for tissue engineering].

BACKGROUND: Tissue engineering is a promising method for the generation of chondrogenic grafts for reconstructive surgery. In cultured chondrocytes, the dedifferentiation of cells seems unavoidable for multiplication. METHODS: In this study, we investigated the expression of distinct markers during the dedifferentiation of human chondrocytes (HC) harvested during septoplasty and human mesenchymal stem cells (hMSC) from cartilage biopsies in cell culture using the microarray technique. RESULTS: The genes for collagen 1alpha1, 2alpha1, 3alpha1, 4alpha1, 11alpha1, biglycan, fibromodulin and lumican were activated during the dedifferentiation of the HCs, collagen 9alpha2, 9alpha3, 10alpha1 and chondroadherin were inactivated. During chondrogenic differentiation of hMSCs, the genes for collagen 3alpha1, 9alpha2, 9alpha3, 10alpha1, 11alpha1 were activated, collagen 4alpha1 and fibromodulin inactivated and the genes for Col 1alpha1, biglycan und chondroadherin constantly expressed. CONCLUSION: The genetic profile for the investigated markers in human chondrocytes generated from hMSCs resembles the profile in differentiated chondrocytes. Collagen 2alpha1, 9alpha2, 9alpha3, 10alpha1 could represent markers for the differentiation of chondrocytes, Col 1alpha1, 3alpha1 und 4alpha1, biglycan, fibromodulin and lumican markers for the dedifferentiation into a more fibroblastoid cell type.

Aged↗

PubMed2003

Sperm motion characteristics of Garole rams raised for a prolonged period in a semi-arid tropical environment.

The Garole is a prolific but less well known and rare breed of small sheep found in the hot and humid Sunderban region of West Bengal. An ability to breed throughout the year and to graze in knee-deep water, resistance to foot rot and a strong mothering instinct are some of the special features of this breed. Garole rams could provide germplasm to incorporate prolificacy traits by artificial insemination of the nonprolific sheep breeds found in abundance in the semi-arid and arid tropical climates of India. The aim of the present study was to evaluate the semen production by Garole rams maintained in a semi-arid climate for three years and to objectively assess their semen quality by a computer-assisted sperm analysis technique. The donor rams were randomly selected each year from the original flock procured from their natural habitat or from the offspring born at the Institute farm. Semen was collected weekly for three weeks each autumn for three consecutive years from 8 rams each year. The overall means (SD) of the traits that did not differ significantly with age or year were volume, concentration, curvilinear velocity, average path velocity, amplitude of lateral head displacement, beat frequency, motility and the percentages of rapid motile sperms and of slow motile sperms. The age of the rams had a significant effect (p<0.05) on the straight-line velocity but this was not significantly affected by the length of exposure to the semi-arid climate. However, the age and year had significant effects (p<0.05) on linearity, straightness and the percentage of medium motile sperms. It was concluded that Garole rams are capable of producing good-quality semen even after a prolonged period of exposure to a semi-arid tropical climate.

Animals↗

PubMed1999

A study of toxic effects of heavy metal contaminants from sludge-supplemented diets on male Wistar rats.

Activated sludge is a rich source of nitrogenous matter and has been recommended as cheap supplement in animal feed. It has been incorporated into cattle and poultry feed. It is well known that sewage of purely domestic origin is also contaminated with heavy metals, pesticides, and other organic pollutants. A study was undertaken to determine the toxic effects of heavy metal-contaminated domestic sewage sludge on young male Wistar rats by supplementing dehydrated activated sludge in their diet at concentrations of 5, 10, 15 and 20%. The sludge was found to be contaminated with 1.820 (zinc), 0.273 (nickel), 0.017 (lead), 0.053 (copper), 0.006 (chromium), and 0.005 (cadmium)mg/g of dry sludge, by analysis by atomic absorption spectroscopy. The toxic effects of sludge-supplemented diets on individual groups of rats were assessed by assaying various enzyme activities in serum, liver, muscle, and brain. Levels of serum and liver alanine aminotransferase and succinate dehydrogenase (SDH) were significantly low in all the sludge-supplemented diet-fed (SSDF) rats. Similarly, serum lactate dehydrogenase (LDH) and muscle SDH activity were also significantly reduced in the SSDF rats. On the other hand, liver and muscle LDH, serum and liver aspartate aminotransferase, and serum and muscle alkaline phosphatase activities were significantly higher in all the SSDF animals. Brain and muscle acetylcholinesterase activity was significantly high in all the SSDF groups. This study indicates that even though the sludge is a rich source of nitrogenous matter, its supplementation in poultry and animals feed should be done with caution. Otherwise, the contaminants found in the sludge will biomagnify in the food chain and lead to various toxicological hazards.

Alanine Transaminase↗

PubMed1994

Complicated falciparum malaria.

We studied 50 cases of complicated falciparum malaria in order to evaluate the different clinical presentations. Thirty five had cerebral malaria while 15 presented with extracerebral features including diarrhea and vomiting (n = 6), hepatitis (n = 4), acute renal failure (n = 3), and gastrointestinal bleeding (n = 2). These cases were treated with quinine. Mortality was higher in extracerebral form (33.3%) as compared to cerebral malaria (22%). Our study suggests that even though cerebral malaria remains the single most important cause of high mortality in complicated falciparum malaria, extracerebral presentation of falciparum malaria is equally life threatening and should be viewed seriously.

Cause of Death↗

PubMed1989

Pregnancy and epilepsy.

In a prospective study, 30 pregnant epileptic patients were followed through their pregnancy to determine the effect of seizures on pregnancy and its outcome and the effect of pregnancy on seizures. An attempt was made to correlate the serum hormone and anticonvulsant drug levels with seizure frequency, complications of pregnancy, occurrence of status epilepticus and teratogenicity. In 14 patients seizure frequency increased, in 15 it remained unchanged and in 1 patient it decreased. There were 2 spontaneous abortions, 2 patients had status epilepticus and 1 offspring of a patient had a ventricular septal defect. This patient was receiving carbamazepine and diphenylhydantoin. Patients with increased seizures frequency had significantly higher oestrogen levels, lower level of progesterone and lower level of anticonvulsant drugs as compared with those with no change in seizures. Patients who had abortions and those who developed status epilepticus had high serum oestrogen levels.

Abnormalities, Drug-Induced↗