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Biomedical subjects

V Rai

Publications and source records attributed to V Rai.

At least 19 recordsLinked to original sources

Efficient dynamic Monte Carlo algorithm for time-dependent catalytic surface chemistry.

Several numerical algorithms for dynamic Monte Carlo simulations of surface chemistry have been proposed in the past. The variable step size method (VSSM) is commonly used for systems where the rate coefficients are constant in time, owing to its good efficiency. If rate coefficients vary in time, the first reaction method (FRM) has been shown to be more efficient. However, the cost of this algorithm to execute a reaction step depends on the considered lattice size, which can make this method inefficient for systems involving surface phenomena on different scales. Here we propose a general and efficient algorithm, the fast first reaction method (fFRM), which has the advantages of being applicable to systems with constant and time-varying rate coefficients, and of having a computational cost per reaction step that is independent of the lattice size. An additional feature of fFRM is that it is rejection-free, which means that once a reaction class is selected, a reaction of that type will be executed. A rejection-free variant of VSSM, called rVSSM, is also presented, which leads to an approximately 15% speedup compared with the VSSM algorithm for the considered example.

Journal Article↗

Unusual appearance of retroperitoneal fibrosis simulating a tumour.

Retroperitoneal fibrosis (RPF) is an uncommon entity that usually presents as a fibrous plaque-like lesion that encases the aorta and inferior vena cava below the level of the renal arteries. We present an unusual mass-like appearance of this disease simulating a tumour, with foci of calcification, seen in a young girl.

Adolescent↗

Chromium in some herbal drugs.

The use and demand of herbal drug is increasing day by day in both developing and developed countries due to the growing recognition that these are natural products having no or little side effects and can easily be available at affordable prices. Sometimes these are the only source of health care available to poor people particularly in South East Asia where more than 80% population depend on herbal drugs for their health care needs. Thus the quality and safety of herbal products is very important in order to have desired therapeutic efficacy. But in today's polluted environment with increasing automobile consumption and industrialization, WHO is emphasizing emphatically that without heavy metal assessment the herbal drug should not be used. The concentration of heavy metals including Cr is increasing in the environment and many hazardous effects are caused in the inhabitants of that environment (Prasad and Hagemeyer, 1999; Nriagu and Pacyna, 1998). For example, in human beings, due to Cr numbers of disorders occur like damage to liver, kidney, respiratory and nerve tissues. Besides enhancing risk of human lung cancer due to automobile exhaust and even irritation of skin have also been reported by excess of Cr (Anonymous, 1998; Anonymous 1988). Therefore it is mandatory to assess the Cr concentration in herbal drugs before use. Although some work has been carried out by Rai et al., 2001 a, b; Fuh et al., 2003; Al Ajasa et al., 2004 and Ernst 2002 but it is not enough and lot of work is required in this field.

Chromium↗

Tenascin is differentially expressed in endometrium and endometriosis.

Endometriosis is characterized by the presence of functional endometrial tissue outside the uterine cavity, most commonly on the ovary and peritoneum. The aetiology of endometriosis is not understood, although the adhesion of endometrial cells to the extracellular matrix (ECM) would be expected to play a central role in its pathogenesis. The expression of ECM molecules in endometrium and in endometriosis has been investigated using immunohistochemistry and western blotting techniques. The ECM components collagen IV, laminin, vitronectin, and fibronectin had a similar pattern of expression throughout the menstrual cycle in endometrium and endometriosis. Expression of tenascin was elevated in the stroma of the functionalis region of the endometrium during the proliferative stage of the menstrual cycle and in endometriosis. Tenascin expression in endometriosis was not modulated according to the stage of the menstrual cycle. It is concluded that expression of tenascin is strictly regulated in endometrium and may be important in endometrial regeneration and in the pathogenesis of endometriosis.

Adult↗

Prenatal sonographic diagnosis of skeletal dysplasias--a report of the diagnostic and prognostic accuracy in 35 cases.

Sonographic assessment of the skeleton is a routine part of fetal anomaly scanning. We report a series of 35 cases seen during a 7-year interval in which a skeletal dysplasia was suspected prenatally. In seven (20 per cent) of the 35 cases, a specific diagnosis could not be made either pre- or postnatally. Follow-up was incomplete in one case. In 32 (91 per cent) of the 35 cases, prenatal sonographic examination correctly predicted the prognosis, although in only 11 (31 per cent) of the 35 cases was the suggested prenatal diagnosis proven to be correct. The difficulty of making an accurate prenatal sonographic diagnosis in fetuses with suspected skeletal dysplasias throughout gestation, especially in the third trimester, and the importance of comprehensive multidisciplinary postnatal assessment in these cases are emphasized.

Abortion, Induced↗

Presence of fetal DNA in maternal plasma and serum.

BACKGROUND: The potential use of plasma and serum for molecular diagnosis has generated interest. Tumour DNA has been found in 'the plasma and serum of cancer patients, and molecular analysis has been done on this material. We investigated the equivalent condition in pregnancy-that is, whether fetal DNA is present in maternal plasma and serum. METHODS: We used a rapid-boiling method to extract DNA from plasma and serum. DNA from plasma, serum, and nucleated blood cells from 43 pregnant women underwent a sensitive Y-PCR assay to detect circulating male fetal DNA from women bearing male fetuses. FINDINGS: Fetus-derived Y sequences were detected in 24 (80%) of the 30 maternal plasma samples, and in 21 (70%) of the 30 maternal serum samples, from women bearing male fetuses. These results were obtained with only 10 microL of the samples. When DNA from nucleated blood cells extracted from a similar volume of blood was used, only five (17%) of the 30 samples gave a positive Y signal. None of the 13 women bearing female fetuses, and none of the ten non-pregnant control women, had positive results for plasma, serum or nucleated blood cells. INTERPRETATION: Our finding of circulating fetal DNA in maternal plasma may have implications for non-invasive prenatal diagnosis, and for improving our understanding of the fetomaternal relationship.

Case-Control Studies↗

Effect of Tulasi (Ocimum sanctum) leaf powder supplementation on blood sugar levels, serum lipids and tissue lipids in diabetic rats.

Tulasi leaf powder was fed at the 1% level in normal and diabetic rats for a period of one month to explore the effect on fasting blood sugar, uronic acid, total amino acids, and the lipid profile in serum and tissue lipids. The results indicated a significant reduction in fasting blood sugar, uronic acid, total amino acids, total cholesterol, triglyceride, phospholipids and total lipids. In liver, total cholesterol, triglyceride and total lipids were significantly lowered. Total lipids were significantly reduced in kidney. In heart, a significant fall in total cholesterol and phospholipids was observed. All these observations indicate the hypoglycemic and hypolipidemic effect of Tulasi in diabetic rats.

Amino Acids↗

Comparison of thermostable phosphatase and proteases from thermophilically disposed transition species and thermophilic actinomycetes.

Thermoactinomycetes vulgaris is a thermophilic actinomycetes growing optimally at 50 degrees C and Streptomyces albus, S. coelicolor, S. fasciculus and S. olivochromogenes are thermophilically disposed transition species of actinomycetes, which have optimum biomass at 40 degrees C. The acid/alkaline phosphatase and acid/alkaline/neutral protease enzyme from Streptomycetes species showed enzyme activity up to 90 degrees C. In comparison to phosphatases and proteases from T. vulgaris it was concluded that these thermophilically disposed transition species showed macromolecular thermostability i.e. thermostable enzymes and protein.

Endopeptidases↗

Integrins alpha 3 and alpha 6 are differentially expressed in endometrium and endometriosis.

The expression of integrin subunits has been investigated in the stroma and epithelium of eutopic and ectopic endometrial tissues, using immunohistochemistry and fluorescently activated cell-sorting techniques. Integrin subunits exhibited tissue-specific expression in both eutopic and ectopic endometrium. Integrin alpha 3 subunit was up-regulated in ectopic endometrium compared with the eutopic counterpart, whereas alpha 6 integrin subunit was down-regulated in the ectopic tissues. Cycle stage-dependent expression of alpha v and beta 3, observed in eutopic endometrium, was absent in the ectopic counterpart. It is concluded that the development and regeneration of the endometrium involve complex integrin-ligand interactions and that regulation of specific adhesive events is lost in endometriosis.

Adult↗

Randomized placebo-controlled, single blind trial of holy basil leaves in patients with noninsulin-dependent diabetes mellitus.

Experimental studies on albino rats reported that leaf extract of Ocimum sanctum and Ocimum album (holy basil) had hypoglycemic effect. To explore further evidence we studied the effects of treatment with holy basil leaves on fasting and postprandial blood glucose and serum cholesterol levels in humans through randomized, placebo-controlled, crossover single blind trial. Results indicated a significant decrease in fasting and postprandial blood glucose levels during treatment with holy basil leaves compared to during treatment with placebo leaves. Fasting blood glucose fell by 21.0 mg/dl, confidence interval of difference -31.4 - (-)11.2 (p < 0.001), and postprandial blood glucose fell by 15.8 mg/dl, confidence interval -27.0 - (-)5.6 (p < 0.02). The lower values of glucose represented reductions of 17.6% and 7.3% in the levels of fasting and postprandial blood glucose, respectively. Urine glucose levels showed similar trend. Mean total cholesterol levels showed mild reduction during basil treatment period. The findings from this study suggest that basil leaves may be prescribed as adjunct to dietary therapy and drug treatment in mild to moderate NIDDM.

Adult↗

Relationship between amino acid dose and gastric secretory response.

Gastric secretory dose-response studies, using an 8.5% mixed L-amino acid solution as the agonist, were carried out in three dogs with Heidenhain pouches and gastric fistulae. Secretory responses of the Heidenhain pouches were measured during two hour infusions of amino acids given at rates of 0, 0.05, 0.1, 0.2, 0.4, 0.8, and 1.6 g/kg/h and plasma amino nitrogen was measured before and during the infusion. Three separate studies at each dose level were made in each dog. The maximum secretory response occurred at the dose of 0.4 g/kg/h and amounted to approximately 20% of the maximal histamine response. Larger doses produced no additional increase in secretion or an actual decrease in secretory rate. It is concluded that the solution of amino acids used acts as a modest gastric agonist and that increases in plasma amino nitrogen such as may be observed after a protein meal are capable of eliciting a slight, but definite, gastric secretory response.

Amino Acids↗

Tinidazole and metronidazole in the treatment of amoebic liver abscess.

Tinidazole, a new drug effective against E histolytica, was studied in patients with amoebic liver abscess proved by aspiration of pus. A preliminary open evaluation in fourteen patients provided a cure in all cases. A subsequent comparative study against metronidazole in another twenty-two patients led to a cure in all eleven patients treated with tinidazole and in ten out of eleven patients treated with metronidazole. The response was faster in patients treated with tinidazole. Tinidazole was totally free from side-effects. Tinidazole is a noteworthy addition to anti-amoebic therapy.

Adult↗