Biomedical subjects

S Kapoor

Publications and source records attributed to S Kapoor.

At least 55 records · Page 3Linked to original sources

PubMed2000

Age prediction based on skeletal morphology.

Treatment plan for a child requires a complete diagnosis with monitoring of the skeleto-dental morphological changes during active period of growth. Growth modifications are done while the forces of growth are still at the peak of activity in a developing child. This study was undertaken on lateral cephalograms of 100 North Indian samples in the age group of 9-12 years consisting of 50 males and 50 females divided into normal occlusion and malocclusion groups, to predict and assess age by evaluating the skeleto-dental morphology in developing normal children having flush terminal plane molar relationship and children with developing class II pattern. It was concluded that based on measurements used in the study of dentofacial morphology, the age of a child could be statistically determined.

Age Determination by Skeleton↗

PubMed1999

Systemic biosynthesis of prostacyclin by cyclooxygenase (COX)-2: the human pharmacology of a selective inhibitor of COX-2.

Prostaglandins (PG) are synthesized by two isoforms of the enzyme PG G/H synthase [cyclooxygenase (COX)]. To examine selectivity of tolerated doses of an inhibitor of the inducible COX-2 in humans, we examined the effects of celecoxib on indices of COX-1-dependent platelet thromboxane (Tx) A2 and on systemic biosynthesis of prostacyclin in vivo. Volunteers received doses of 100, 400, or 800 mg of celecoxib or 800 mg of a nonselective inhibitor, ibuprofen. Ibuprofen, but not celecoxib, significantly inhibited TxA2-dependent aggregation, induced ex vivo by arachidonic acid (83 +/- 11% vs. 11. 9 +/- 2.2%; P < 0.005) and by collagen. Neither agent altered aggregation induced by thromboxane mimetic, U46619. Ibuprofen reduced serum TxB2 (-95 +/- 2% vs. -6.9 +/- 4.2%; P < 0.001) and urinary excretion of the major Tx metabolite, 11-dehydro TxB2 (-70 +/- 9.9% vs. -20.3 +/- 5.3%; P < 0.05) when compared with placebo. Despite a failure to suppress TxA2-dependant platelet aggregation, celecoxib had a modest but significant inhibitory effect on serum TxB2 4 hr after dosing. By contrast, both ibuprofen and celecoxib suppressed a biochemical index of COX-2 activity (endotoxin induced PGE2 in whole blood ex vivo) to a comparable degree (-93.3 +/- 2% vs. -83 +/- 6.1%). There was no significant difference between the doses of celecoxib on COX-2 inhibition. Celecoxib and ibuprofen suppressed urinary excretion of the prostacyclin metabolite 2,3 dinor 6-keto PGF1alpha. These data suggest that (i) platelet COX-1-dependent aggregation is not inhibited by up to 800 mg of celecoxib; (ii) comparable COX-2 inhibition is attained by celecoxib (100-800 mg) and ibuprofen (800 mg) after acute dosing; and (iii) COX-2 is a major source of systemic prostacyclin biosynthesis in healthy humans.

6-Ketoprostaglandin F1 alpha↗

PubMed1999

Fine needle aspiration biopsy of the spleen in pyrexia of unknown origin.

To evaluate the diagnostic utility, value and potential risk of fine needle aspiration biopsy of spleen (sFNAB) in patients with splenomegaly in pyrexia of unknown origin (PUO), a retrospective analysis of medical records and cytological material of 31 patients on whom FNAB was performed between April 1994 and October 1997 was done. The patients were HIV- and presented with PUO. All other relevant investigations were negative. The spleen was either palpable or detected to have space-occupying lesions on ultrasonography (USG). The splenic aspirates showed tuberculosis in 11 patients (35.4%) and inconclusive or reactive changes in nine patients (25.8%). One case out of this group proved to be Kaposi's sarcoma on autopsy. The other diseases encountered were leishmaniasis (n = 3), non-Hodgkin's lymphoma (n = 4), fungal infections (n = 2), Hodgkin's lymphoma (n = 1). The patients who were diagnosed as having tuberculosis had epithelioid cells, giant cells, necrosis and inflammatory cells in various combinations. AFB positivity was 63.6%. The other cases which showed granulomas but no AFB were diagnosed on empirical grounds and all responded to the anti-tuberculosis therapy. No complications were encountered with the procedure. Therefore the authors conclude that sFNAB is rewarding in patients where all other non-invasive modalities of diagnosis have failed.

Adult↗

PubMed1999

Long-term histologic effects of the CO2 laser.

The long-term histologic effects of CO2 laser resurfacing previously were unknown. Prior investigations have clearly defined the photothermal effect. Collagen shrinkage as a reaction to increased tissue temperature between 60 and 70 degrees C has also been previously described. Twenty-two patients completed a 1-year study in which biopsy specimens from the upper lip were taken preoperatively and 6 weeks, 6 months, and 1 year after CO2 laser resurfacing. Trichrome stains and Verhoeff-van Gieson stains were used to demonstrate tissue collagen and tissue elastin. Neocollagenesis beginning at 6 weeks and progressively increasing at 6 months and 1 year was clearly demonstrated. Neoelastogenesis showed significant increases at 6 months and 1 year. It is hypothesized that the additive effects of initial collagen shrinkage and the long-term effect of neocollagenesis and neoelastogenesis are the significant factors contributing to the long-lasting and excellent results of CO2 laser skin resurfacing.

Adult↗

PubMed1999

Identification of two essential sequence elements in the nonconsensus type II PatpB-290 plastid promoter by using plastid transcription extracts from cultured tobacco BY-2 cells.

In higher plants, plastid genes are transcribed by at least two types of DNA-dependent RNA polymerases. One of them is the well-known plastid-encoded prokaryotic type of polymerase that recognizes sigma(70)-type promoters consisting of -35 and -10 consensus elements. The other recently recognized RNA polymerase has been found to be encoded entirely in the nucleus, and it recognizes a completely different set of promoters, designated previously as nonconsensus type II (NCII) promoters. Here, we report the development of an in vitro transcription system using nonphotosynthetic plastids of cultured tobacco BY-2 cells. This system preferentially and accurately initiates transcription from NCII promoters. The conditions for in vitro transcription were optimized by using the tobacco PatpB-290 promoter, which has been found to be the most highly expressed NCII promoter in vivo. Analysis of in vitro transcription initiation in a series of PatpB-290 5' deletion constructs revealed that sequences upstream of nucleotide -41 do not influence the transcriptional activity of this promoter. A 43-bp region (nucleotides -35 to +8) was further analyzed by introducing single or multiple nucleotide substitutions into two regions (box I and box II) of high sequence conservation. We report here that the ATAGAA sequence comprising box II and the -11 to +4 region (relative to transcription initiation) in box I significantly influence the activity of this NCII promoter.

Base Sequence↗

PubMed1999

The effect of dehydroepiandrosterone supplementation to symptomatic perimenopausal women on serum endocrine profiles, lipid parameters, and health-related quality of life.

Dehydroepiandrosterone (DHEA), an androgenic steroid hormone, exhibits an age-related decline. Perimenopausal women have only approximately 50% of peak DHEA levels. Despite limited scientific data, DHEA has gained recognition as a dietary supplement to reduce the symptoms of aging and improve well-being. This randomized, double-blind placebo-controlled trial examined the effects of 50 mg/day of oral DHEA supplementation, for 3 months, on 60 perimenopausal women with complaints of altered mood and well-being. Changes in the serum endocrine profile of women in the DHEA group were significantly greater than the placebo group, including a 242% [95% confidence interval (CI) +60.1, +423.9] increase in DHEAS, a 94.8% (95% CI +34.2, +155.4) increase in testosterone, and a 13.2% (95% CI -27.88, +0.5) decline in cortisol compared to baseline. Women receiving DHEA had a 10.1% (95% CI -15.0, -5.1) decline in high-density lipoprotein and an 18.1% (95% CI -32.2, -3.9) decline in Lp(a) from baseline, but these declines did not significantly differ from women who received placebo. Women receiving DHEA did not have any improvements significantly greater than placebo in the severity of perimenopausal symptoms, mood, dysphoria, libido, cognition, memory, or well-being. DHEA supplementation significantly effects the endocrine profile, may affect the lipid profile, but does not improve perimenopausal symptoms or well-being compared to placebo.

Affect↗

PubMed1999

Effects of specific inhibition of cyclooxygenase-2 on sodium balance, hemodynamics, and vasoactive eicosanoids.

Conventional nonsteroidal anti-inflammatory drugs inhibit both cyclooxygenase (Cox) isoforms (Cox-1 and Cox-2) and may be associated with nephrotoxicity. The present study was undertaken to assess the renal effects of the specific Cox-2 inhibitor, MK-966. Healthy older adults (n = 36) were admitted to a clinical research unit, placed on a fixed sodium intake, and randomized under double-blind conditions to receive the specific Cox-2 inhibitor, MK-966 (50 mg every day), a nonspecific Cox-1/Cox-2 inhibitor, indomethacin (50 mg t.i.d.), or placebo for 2 weeks. All treatments were well tolerated. Both active regimens were associated with a transient but significant decline in urinary sodium excretion during the first 72 h of treatment. Blood pressure and body weight did not change significantly in any group. The glomerular filtration rate (GFR) was decreased by indomethacin but was not changed significantly by MK-966 treatment. Thromboxane biosynthesis by platelets was inhibited by indomethacin only. The urinary excretion of the prostacyclin metabolite 2,3-dinor-6-keto prostaglandin F1alpha was decreased by both MK-966 and indomethacin and was unchanged by placebo. Cox-2 may play a role in the systemic biosynthesis of prostacyclin in healthy humans. Selective inhibition of Cox-2 by MK-966 caused a clinically insignificant and transient retention of sodium, but no depression of GFR. Inhibition of both Cox isoforms by indomethacin caused transient sodium retention and a decline in GFR. Our data suggest that acute sodium retention by nonsteroidal anti-inflammatory drugs in healthy elderly subjects is mediated by the inhibition of Cox-2, whereas depression of GFR is due to inhibition of Cox-1.

6-Ketoprostaglandin F1 alpha↗

PubMed1999

A clinical study of the patients with dengue hemorrhagic fever during the epidemic of 1996 at Lucknow, India.

This paper describes the clinical findings in 206 patients with dengue fever (DF) or with dengue hemorrhagic fever (DHF) during the epidemic of 1996 at Lucknow. The age group affected most was 11 to 30 years and 21% of the patients were less than 10 years old. The male:female ratio was 1.9:1. The onset was abrupt in all the patients, severe frontal headache was observed in 97%, myalgia in 90%, skin rash in 40%, vomiting in 29% and arthralgia in knee and hip joints in 9%. Anuria was seen in two patients. Lymphadenopathy was noted in 14%, hepatomegaly in 4%, being associated with mild jaundice in one patient, and splenomegaly in 2% of the patients. Involvement of the heart and lungs was seen in one patient each and no case with encephalitis was recorded. Hemorrhages from various sites were observed in 54% patients and 17 patients had profound shock. The commonest bleeding site was gums. Profound shock was preceded by various warning signs, the commonest being sudden hypotension. Among the patients with profound shock the mortality was 47% while the overall fatality rate was 3.8%. A number of the risk factors existed for a long time in this part of the world, but what precipitated the present epidemic at this time, is not known.

Adolescent↗

PubMed1998

Elevated levels of IL-8 in dengue hemorrhagic fever.

Dengue virus causes dengue fever, a mild febrile illness, and at times dengue hemorrhagic fever (DHF), a severe illness the pathogenesis of which is not fully understood. Given the crucial roles played by interleukin-8 (IL-8) as a chemoattractant cytokine and in inflammatory processes, levels of circulating IL-8 in the sera and IL-8 mRNA in the peripheral blood mononuclear cells (PBMC) were measured in 99 patients of a recent dengue epidemic that occurred in India in 1996 and in 21 normal healthy controls. Twenty-six of the patients had dengue fever (DF) and the remaining 73 were diagnosed as having different grades of DHF. All the control normal sera were negative for IL-8, so were their PBMC for IL-8 mRNA. Increased levels of IL-8 in the sera and IL-8 mRNA in their PBMC were observed in patients with severe illness of DHF grades III and IV. Only two out of 26 patients of DF and one out of 10 DHF grade I patient were positive for IL-8 and all three deteriorated to DHF grade IV within 24 hr. All six patients of DHF grade IV who died had higher serum level of IL-8 above 200 pg/ml, the highest being 5,568 pg/ml in one patient; the presence of mRNA for IL-8 was very high in all patients. A striking correlation was observed between increased levels of IL-8 and severe DHF, with greater levels in patients with increased grade of the disease and death. These results suggest that IL-8 may have an important role and may be an indicator of increasing severity of the disease and death.

Adolescent↗

PubMed1998

Transcript analysis of the tobacco plastid operon rps2/atpI/H/F/A reveals the existence of a non-consensus type II (NCII) promoter upstream of the atpI coding sequence.

The plastid ATP synthase complex is composed of nine subunits, of which six are encoded in the plastome. The plastid-encoded genes are arranged in two transcriptional units: atpB/E and atpI/H/F/A. We have recently reported that besides containing four -10 and -35 consensus-type (CT) promoters, the atpB/E operon also contains a non-consensus type (NCII) promoter that alone is responsible for its expression in non-photosynthetic plastids. As the functionality of ATP synthase requires expression of all nine subunits, NCII promoter-driven transcription of the atpI/H/F/A operon is to be expected in non-photosynthetic plastids. Therefore, a detailed transcriptional analysis of this operon was carried out using RNA samples from tobacco leaf, cultured cells (BY-2) and seedlings grown on streptomycin and spectinomycin; which contain chloroplasts, translationally active non-photosynthetic plastids and translationally inactive plastids, respectively. We identified a total of three transcription initiation sites (TIS) and four transcript processing sites in the non-coding regions of this operon. Our results also demonstrate that rps2 is co-transcribed with the atpI/H/F/A genes. One of the TIS (-208 atpI) is characterized by an NCII type promoter, while other two primary transcripts (-131 atpI and -384 atpH) initiate from CT promoters. In non-photosynthetic plastids the atpI/H/F/A-specific transcript pool seems to be solely contributed by initiation at the -208 atpI (NCII type) promoter, because transcripts from CT promoters do not accumulate in these plastid types.

Base Sequence↗

PubMed1998

Production of cytotoxic factor by peripheral blood mononuclear cells (PBMC) in patients with dengue haemorrhagic fever.

A unique cytokine, human cytotoxic factor (hCF), has been shown to occur in the sera of patients with dengue fever (DF) and dengue haemorrhagic fever (DHF). The present study was undertaken to investigate the ability of fresh PBMC of such patients to produce hCF. The PBMC were cultured for 24 h and the culture supernatants (CS) were analysed for the presence of hCF by cytotoxicity assay, competitive ELISA and dot blot tests. In 90% of 246 cases CS were positive for hCF by the three tests. CS were positive for hCF in PBMC collected from days 1-20 of illness but not at later periods. Higher cytotoxic activity was observed in CS of days 1-4 of illness and was highest in cases of DHF grade IV and lowest in cases of DF. Dot blot hybridization of RNA extracted from the PBMC of the patients showed the presence of mRNA for hCF in 94% of cases. A similar number of patients showed the presence of hCF in situ in the PBMC smears by fluorescent antibody technique. hCF was found only in CD4+ T cells. The findings thus present direct evidence of the production of hCF by CD4 T cells of cases of DF/DHF.

Cytokines↗

PubMed1998

5/6/7/8 mono or disubstituted 1H/1-phenyl-9H-pyrido [3,4 b] indoles--a new class of antifilarial agents and their relationship with voltage sensitive calcium channels in Setaria cervi.

Synthetic compounds of 5/6/7/8 mono or disubstituted 1H/1-phenyl-9H pyrido (3,4 b) indole series were screened for their antifilarial activity in vitro by observing their effect on the spontaneous movements of the whole worm and nerve muscle preparation of S. cervi (Nematoda:Filarioidea). Of the 10 compounds tested only compound 87/581 was able to modify the movements of whole worm and nerve muscle preparation. This compound caused inhibition of spontaneous motility of whole worm and nerve muscle preparation of S. cervi characterized by initial short lasting stimulation followed by irreversible paralysis. The concentration required to inhibit the movements of n.m. preparation was 10 micrograms/ml as compared to 25 micrograms/ml for the whole worm preparation, suggesting a cuticular permeability barrier. Prior addition of compound 87/581 to the bath fluid blocked the calcium ion dependent stimulant effect of Ach and pyrantel pamoate. Further the initial stimulant effect of the compound was blocked by prior addition of nifedipine a calcium channel blocker. The findings suggest that the action is due to blockade of voltage sensitive calcium channels.

Animals↗

PubMed1997

Identification and functional significance of a new class of non-consensus-type plastid promoters.

The promoter regions of most plastid transcription units have been reported to consist of prokaryotic -10 and -35-like consensus sequences. However, a few promoters with no homology to the consensus elements have also been characterized. A novel class of non-consensus plastid promoters--designated as non consensus type II (NC-II) promoters--that effect low-level constitutive expression of respective genes in photosynthetic as well as non-photosynthetic plastids is described in this paper. The abundance of NC-II promoter-derived transcripts remains unaltered even when light-grown seedlings are shifted to the dark. In contrast, transcripts from -10 and -35-like elements containing consensus type (CT) promoters accumulate to high levels in chloroplasts as compared with non-photosynthetic plastids of roots and cultured cells. Moreover, accumulation of these transcripts is greatly affected by light. The inhibition of plastid protein synthesis has no apparent effect on the abundance of the NC-II transcripts whereas levels of CT transcripts are greatly reduced. In vivo tagetitoxin (a plastid transcription inhibitor) treatment also reduces the levels of CT transcripts with no apparent inhibitory effect on the accumulation of NC-II transcripts. The accumulation of transcripts from both classes of promoters, however, is reduced when cytoplasmic protein synthesis is inhibited by in vivo treatment with cycloheximide. The results are suggestive of the possible existence of at least two distinctive systems for the synthesis and/or maintenance of plastid transcripts which differentiate between two classes of transcripts in a promoter-type specific manner.

Base Sequence↗

PubMed1997

The significance of white-centered retinal hemorrhages in the shaken baby syndrome.

Retinal hemorrhages in healthy children with or without a history of associated trauma are a strong indicator of child abuse. This report describes six cases of battered infants who presented with white-centered retinal hemorrhages. We discuss potential mechanisms for the presence of white-centered retinal hemorrhages in battered children.

Battered Child Syndrome↗

PubMed1997

Prostaglandin production contributes to exercise-induced vasodilation in heart failure.

Endothelial release of prostaglandins may contribute to exercise-induced skeletal muscle arteriolar vasodilation in patients with heart failure. To test this hypothesis, we examined the effect of indomethacin on leg circulation and metabolism in eight chronic heart failure patients, aged 55 +/- 4 yr. Central hemodynamics and leg blood flow, determined by thermodilution, and leg metabolic parameters were measured during maximum treadmill exercise before and 2 h after oral administration of indomethacin (75 mg). Leg release of 6-ketoprostaglandin F1alpha was also measured. During control exercise, leg blood flow increased from 0.34 +/- 0.03 to 1. 99 +/- 0.19 l/min (P < 0.001), leg O2 consumption from 13.6 +/- 1.8 to 164.5 +/- 16.2 ml/min (P < 0.001), and leg prostanoid release from 54.1 +/- 8.5 to 267.4 +/- 35.8 pg/min (P < 0.001). Indomethacin suppressed release of prostaglandin F1alpha (P < 0.001) throughout exercise and decreased leg blood flow during exercise (P < 0.05). This was associated with a corresponding decrease in leg O2 consumption (P < 0.05) and a higher level of femoral venous lactate at peak exercise (P < 0.01). These data suggest that release of vasodilatory prostaglandins contributes to skeletal muscle arteriolar vasodilation in patients with heart failure.

Cyclooxygenase Inhibitors↗

PubMed1997

Increased renal production of transforming growth factor-beta1 in patients with type II diabetes.

Diabetic nephropathy is a common complication in patients with either type I or type II diabetes. The pathogenesis of diabetic nephropathy is thought to involve both metabolic and vascular factors leading to chronic accumulation of glomerular mesangial matrix. In this context, both transforming growth factor-beta (TGF-beta) and endothelin may contribute to these processes. To determine if diabetic patients demonstrate increased renal production of TGF-beta and endothelin, aortic, renal vein, and urinary levels of these factors were measured in 14 type II diabetic patients and 11 nondiabetic patients who were undergoing elective cardiac catheterization. Renal blood flow was measured in all patients to calculate net mass balance across the kidney. Diabetic patients demonstrated net renal production of immunoreactive TGF-beta1 (830 +/- 429 ng/min [mean +/- SE]), whereas nondiabetic patients demonstrated net renal extraction of circulating TGF-beta1 (-3479 +/- 1010 ng/min, P < 0.001). Urinary levels of bioassayable TGF-beta were also significantly increased in diabetic patients compared with nondiabetic patients (2.435 +/- 0.385 vs. 0.569 +/- 0.190 ng/mg creatinine, respectively; P < 0.001). Renal production of immunoreactive endothelin was not significantly increased in diabetic patients. In summary, type II diabetes is associated with enhanced net renal production of TGF-beta1, whereas nondiabetic patients exhibit net renal extraction of circulating TGF-beta1. Increased renal TGF-beta production may be an important manifestation of diabetic kidney disease.

Aged↗

PubMed1997

ESR and iron status in pregnancy.

ESR (Westergen) correlated significantly with the iron status (as measured by Hb concentration, haematocrit, red cell count, MCH, P/H ratio, serum iron, TIBC and percent saturation of transferrin) in a group of pregnant women (PW) at term. Serum ferritin correlated negatively with the ESR but the correlation was not statistically significant. Serum ferritin levels of < 50 micrograms/L were present in 9 (34.6%) PW with ESR > or = 50 mm 1st hour and 5 (19.2%) PW with ESR < 50 mm 1st hour. The mean ESR in PW was 55.7 (+/- 22.9) and was > or = 50 mm 1st hour in 50% and < 75 mm 1st hour in 82.7%. The difference in the mean ESR in anaemic and nonanaemic PW was highly significant (p < 0.001), 87.5% anaemic PW with serum ferritin > 50 micrograms/L had ESR > or = 50 mm 1st hour, suggesting the possible effect of chronic infection in raising ferritin levels in these PW.

Blood Sedimentation↗

PubMed1996

Bilin chromophores as reporters of unique protein conformations of phycocyanin 645.

At 45 degrees C, phycocyanin 645 maximally undergoes a reversible and stable conformational change. The change is observed in the visible (chromophore) region of the absorption and circular dichroism (CD) spectra. In the absorption spectrum, the absorbance is lower at 45 degrees C but remains much closer to the normal spectrum than to a strongly denatured spectrum. In the CD, a similar situation exists except that a negative band on the blue edge of the spectrum is much more strongly affected at 45 degrees C than the other bands. On returning to 20 degrees C, all these changes are restored to the original states. The protein is an alpha 2 beta 2 dimer at both 20 and 45 degrees C, and CD in the far-UV shows the identical protein secondary structures at both 20 and 45 degrees C. Fluorescence studies show that energy transfer occurs at both temperatures. At 50 degrees C the results are saliently different as the secondary structure changes and the spectral changes are mostly irreversible. At 50 degrees C, some monomers (alpha beta) are produced, and these monomers are very unstable at that temperature, resulting in the formation of some fully denatured polypeptides. Stable monomers can be produced at 20 degrees C and have visible absorption and CD spectra identical to the dimer at 45 degrees C. Therefore, the chromophores are reporting a tertiary conformational change at 45 degrees C, in which the two halves of the dimer each assume a monomer-like conformation prior to dissociating. These results are compared with a hypothesis for the chromophore topography, and the CD change at the blue edge of the spectra may result from the separation at 45 degrees C of a chromophore pair.

Bile Pigments↗