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R Agrawal

Publications and source records attributed to R Agrawal.

At least 55 records · Page 3Linked to original sources
PubMed1998

Implications of using follicle-stimulating hormone preparations depleted of luteinizing hormone to achieve follicular growth in in vitro fertilization.

We aimed to compare the outcome of in vitro fertilization (IVF) treatment using follicle-stimulating hormone (FSH) containing gonadotropins with human menopausal gonadotropin (hMG) containing gonadotropins for ovarian stimulation. A retrospective analysis of 82 patients undergoing IVF in a private fertility clinic was performed over a specific period of time. Eighteen women received hMG, 20 received Normegon and 44 received FSH. In addition, 17 of these patients received hMG in one cycle and FSH in the other. The main outcome measures studied were duration of treatment, dose of gonadotropins required to achieve optimum follicular growth, number and size of follicles, endometrial thickness, serum estradiol concentrations, number of oocytes retrieved, pregnancy rates and the incidence of ovarian hyperstimulation syndrome (OHSS). At the time of administration of human chorionic gonadotropin (hCG), the mean (+/- SD) serum estradiol concentrations in patients treated with preparations containing FSH and luteinizing hormone (LH) in a ratio of 1:1 was 10,044.3 +/- 5378.8 pmol/l compared with 6819.5 +/- 2597.9 pmol/l in patients treated with preparations with FSH and LH in a ratio of 3:1 and 7369 +/- 4300 pmol/l in patients treated with FSH. The differences between the first and the second two groups were significant (p < 0.05). Endometrial thickness in the three groups of patients were 11 +/- 1.7 mm, 11 +/- 1.5 mm and 9.7 +/- 1.5 mm, respectively (p < 0.001). Comparing cycles of treatment with hMG and FSH in the same patient, we found significantly higher estradiol levels, thicker endometrium, more developing follicles and a shorter duration of treatment in the hMG-treated cycles compared with those in FSH-treated cycles. However, there were no differences between the incidence of OHSS or the pregnancy rates between the three treatment groups. With the advent of recombinant human FSH and the shortage of LH-containing preparations, it is important to note that serum estradiol concentrations on the day of administration of hCG underrepresent the degree of follicular maturation. In the context of the use of a 'long' protocol of gonadotropin-releasing hormone (GnRH) analog therapy and LH-depleted gonadotropin preparations, serum estradiol is no longer a reliable marker of follicle development.

Adult↗
PubMed1997

Gene transfer into the carotid artery using an adventitial collar: comparison of the effectiveness of the plasmid-liposome complexes, retroviruses, pseudotyped retroviruses, and adenoviruses.

We studied the efficiency of plasmid/liposome complexes, Moloney murine leukemia virus-derived (MMLV) retroviruses, pseudotyped vesicular stomatitis virus protein-G (VSV-G)-containing retroviruses, and adenoviruses in delivering genes into the rabbit carotid artery using a silastic collar applied to the adventitia. This method was used for gene transfer because (a) it provides a gene delivery reservoir; (b) no intraluminal manipulations are performed; (c) installation of the collar induces arterial smooth muscle cell (SMC) proliferation and enhances retroviral gene transfer efficiency where target cell proliferation is required. The transfer of the beta-galactosidase (lacZ) marker gene to the adventitia and media occurred with all gene transfer systems. Adenoviruses also transferred the beta-galactosidase gene to some endothelial cells. After 5 days, adenoviral vectors produced the highest gene transfer efficiency with up to 10%+/-6% of cells showing beta-galactosidase activity. Pseudotyped VSV-G retroviruses were also effective in achieving gene transfer in 0.05%+/-0.03% of cells in the adventitia and media. Plasmid/liposome complexes and MMLV retroviruses infected 0.05%+/-0.03% and <0.01%+/-0.01% of cells, respectively. It is concluded that replication-deficient adenoviruses, VSV-G pseudotyped retroviruses, and plasmid/liposome complexes can be used for gene transfer to the arterial wall using the collar method. Because the endothelium remains anatomically present throughout the experiments, the model may be useful for the gene transfer studies involving diffusible or secreted gene products that primarily act on the endothelium. Effects on medial SMC and even endothelium can be achieved from the adventitial side, suggesting an alternative route for the delivery of therapeutically useful genes into the arterial wall.

Adenoviridae↗
PubMed1997

In vitro 6 beta-hydroxylation of progesterone in human renal tissue.

Increased levels of 6 beta-hydroxylated steroids have been found in the urine of several species under different physiological and pathophysiological conditions. Until now, liver, adrenal glands and placenta have been identified as organs which contain 6 beta-hydroxylase activity. However, it has not yet been established whether 6 beta-hydroxylation occurs in mammalian kidney. In this study we have performed in vitro studies with preparations from rat and human kidney cortex and have obtained evidence for the presence of a small but significant renal 6 beta-hydroxylation activity. Two points deserve to be mentioned: 1) A species difference is documented by the presence of the enzyme in human, but not in rat kidney; 2) Substrate specificity is evident. Progesterone, but not corticosterone, was transformed to the 6 beta-hydroxylated metabolite in human tissue. The biological significance of the 6 beta-hydroxylation of endogenous, as well as exogenous steroids could be that 6 beta-hydroxylation opens an alternate route of progesterone metabolism in parallel to other conversion and/or degradation pathways. Furthermore, since other 6 beta-hydroxylated steroids have been reported to exert biological effects, this may also be the case with 6 beta-hydroxy progesterone.

Animals↗
PubMed1997

A multivariate analysis of anatomic success of recurrent retinal detachment treated with pneumatic retinopexy.

PURPOSE: The purpose of the study is to determine the success rate of pneumatic retinopexy (PR) after failed scleral buckling and to elucidate the predictors for anatomic failure by multiple logistic regression analysis. METHODS: Thirty-six eyes with recurrent retinal detachment after failed scleral buckling underwent PR. Intraocular tamponade was attained with SF6 (20 eyes), C3F8 (13 eyes), and air (3 eyes). Median follow-up was 14 months. RESULTS: Retinal reattachment was obtained in 69.4%. Multivariate analysis identified two risk factors for failure: location of retinal break either on the posterior slope or posterior to buckle (P = 0.01) and extent of retinal detachment greater than two quadrants (P = 0.02). CONCLUSIONS: Pneumatic retinopexy is an effective alternative to revision surgical operations if the leaking retinal break is located on the buckle.

Adolescent↗
PubMed1997

Factors influencing the diagnostic accuracy of dobutamine stress echocardiography.

BACKGROUND: While Dobutamine stress echocardiography is a well established tool, the range of the diagnostic accuracy found in the literature is rather large. The main reason for this is the fact, that different test protocols were used. Aim of this study was to assess the effects of both addition of atropine as well as consideration of a hyperdynamic response while interpreting the stress echocardiogram on the diagnostic accuracy. METHODS AND RESULTS: 120 consecutive patients were examined and divided into the following groups: A) achieving their age predicted heart rate with dobutamine, B) termination of the test due to ischemia, C1) negative test without reaching the predicted heart rate, and C2) C1 following addition of atropine. All of the echocardiograms were analyzed twice: 1) regarding the lack of a hyperdynamic response to dobutamine as ischemia (Hyper analysis), and 2) ignoring the hypercontractility (Conventional analysis). The accuracy of A and B were 88% and 90% resp. Group C1 had a very poor accuracy of 60%. This rose significantly (p < 0.01) after atropine (C2 = 84%), without leading to an increase of adverse effects. Conventional wallmotion analysis lead to an overall accuracy of 87% (groups A, B, and C2), while Hyper analysis showed an accuracy of 90% (p < 0.01). CONCLUSIONS: To achieve a high accuracy Dobutamine stress echocardiography should always be combined with atropine to reach a target heart rate. The wallmotion analysis should be based on the assumption that a hyperdynamic response to dobutamine is normal, while its lack is indicative of ischemia.

Adult↗
PubMed1997

Interaction of vesicular stomatitis virus-G pseudotyped retrovirus with CD34+ and CD34+ CD38- hematopoietic progenitor cells.

Retroviral vectors have had limited success in mediating gene transfer to hematopoietic stem cells, particularly in primates, due in part to low or absent expression of the amphotropic receptor (RAM-1). We have been interested in determining whether retrovirus pseudotyped with vesicular stomatitis virus G protein (VSV-G) would allow more efficient gene delivery to hematopoietic stem cells as the VSV-G receptors appear to be ubiquitously present phospholipids. However, we previously found that completion of retroviral vector reverse transcription does not occur in CD34+ CD38- hematopoietic stem cells that were exposed to VSV-G pseudotyped retrovirus. To determine at which stage the block to infection of CD34+ CD38- cells occurs, we confirmed by FACS analysis that VSV-G pseudotyped viral particles could bind to CD34+ CD38- cells. Virus binding to CD34+ cells was saturable at 4 degrees C but nonsaturable at 37 degrees C, up to a multiplicity of infection of 1080. This suggests that surface levels of phospholipid receptors available for viral binding are limiting on CD34+ cells. Cytokine stimulation increased virus binding to CD34+ cells. However, no increase in the level of surface phosphatidylserine (PS), a strong candidate for the VSV-G receptor, was seen as detected by the PS-specific reagent, annexin V. This suggests that another molecule is serving as the VSV-G receptor on CD34+ cells. Here, we show that once virus binding to cytokine-stimulated CD34+ CD38- cells has occurred, virus fusion proceeds efficiently as determined by octadecyl rhodamine (R18) fusion assays. Taken together with our previous observation that reverse transcription does not occur in CD34+ CD38- cells, we suggest that there are intracellular mechanisms leading to blockage of complete reverse transcription of the retrovirus in CD34+ CD38- cells. This has important implications for retrovirus-mediated gene transfer to quiescent stem cells.

ADP-ribosyl Cyclase↗
PubMed1997

Mucin histochemistry--a simple and effective method for diagnosing premalignant and early malignant lesions of lower gastrointestinal tract.

Mucin histochemistry of colo-rectal mucosa was studied in 124 biopsies which included 28 specimens from normal mucosa, 35 inflammatory lesions, 20 polyps, 26 malignant lesions and 15 specimens from transitional mucosa. The stains used were Haematoxylin and Eosin, Periodic acid schiffs, Alcian blue--Periodic acid schiffs (pH 2.5), Orcein--Alcian blue and Periodic acid sodium borohydride saponification. Normal mucosa, mucosa from inflammatory lesions, juvenile and hyperplastic polyps had neutral mucin in traces along with O-acylated sialomucins and sulphomucins. Predominant changes in adenomatous polyps and malignancy were a significant loss of sulphomucins and O-acylation at position C7, C8 or C9 in sialomucins. The changes in transitional mucosa were more on the pattern of malignant lesions. The alterations in the amount and/or pattern of mucin in colorectal mucosa has been found to predate frank morphological changes of malignancy. A routine use of mucin histochemistry in suspicious colorectal biopsies might be helpful in diagnosing premalignant and early malignant lesions in otherwise apparently normal colorectal mucosa or mucosa with chronic inflammatory changes and thereby reduce mortality.

Histocytochemistry↗
PubMed1995

Effects of balloon mitral valvuloplasty on left ventricular muscle function.

Echocardiographically determined ventricular load and performance were compared in 40 consecutive patients with severe mitral stenosis before and 24 h after successful and uncomplicated balloon mitral valvuloplasty in order to clarify the role of loading conditions in causation of reduced left ventricular ejection fraction. After valvuloplasty, mitral valve area increased 2-fold. A modest increase in ejection fraction (53 +/- 11% to 57 +/- 8%, P = 0.021) occurred with an insignificant increase in end-diastolic volume (44 +/- 10 to 48 +/- 16 ml/m2, P = 0.063) and no change in wall stress (61 +/- 19 to 59 +/- 19 kdynes/cm3, P = 0.85) (10(5) dynes = 1 N). There was no correlation between changes in fractional shortening and wall stress (r = 0.07) and between changes in end-diastolic volume and fractional shortening (r = 0.12). Contractile performance estimated by a performance-afterload relation was unchanged after the valvuloplasty. Factors other than a change in loading conditions might be responsible for a modest improvement in ejection performance following mitral valvuloplasty.

Adolescent↗
PubMed1994

[Endocardial fibrosis in neuroendocrine tumors of the gastroenteropancreatic system].

Clinical characteristics, echocardiographic and Doppler echocardiographic findings, as well as serum levels of chromogranin A were recorded on 62 patients (27 women, 35 men; mean age 55 [11-83] years) with histologically confirmed tumours of the gastroenteropancreatic (GEP) system. Changes in the right heart were found in 14 patients (22%), club-like thickening of tricuspid leaflets in 13, tricuspid regurgitation in 14, stenosis in 2 and right atrial or right ventricular dilatation in 11 and 5, respectively. There was no difference between the patients with or without right-heart changes in regard to age, presence of carcinoid syndrome, duration of symptoms, primary tumour site, pattern of metastases, treatment or chromogranin A level. Two patients with nonfunctioning tumours had right-heart changes. While clinical and biochemical parameters did not identify patients with right-heart changes, echocardiography demonstrated all haemodynamically significant endocardial changes. Even patients with nonfunctioning GEP tumours should be regularly monitored by echocardiography.

Adolescent↗
PubMed1994

Improved Doppler assessment of the Bjork-Shiley mitral prosthesis using the continuity equation.

To assess whether derivation of an effective mitral prosthetic valve area using the continuity equation provides an improved functional assessment of the Bjork-Shiley mitral prosthesis over the pressure half-time method, Doppler echocardiographic studies were performed in 43 patients 12 +/- 7 months following the valve replacement. Effective valve orifice area used as the standard for comparison was determined by a hydraulic formula validated in vitro over a wide range of flow rates. All patients were clinically stable, without evidence of prosthetic dysfunction or aortic regurgitation. Prosthetic mitral valve orifice area determined by the hydraulic formula, by the continuity equation and by pressure half-time method for all prostheses sizes averaged 1.6 +/- 0.46 cm2, 1.83 +/- 0.56 cm2 and 2.34 +/- 0.48 cm2, respectively. Effective valve orifice area by the hydraulic formula had a strong correlation with that derived by the continuity equation (r = 0.86; P < 0.0001; standard error of estimate (S.E.E.), 0.12 cm2), but an insignificant correlation with the area calculated by the pressure half-time method (r = 0.24). Prosthetic mitral valve areas determined by the continuity equation and by pressure half-time method also correlated poorly (r = 0.24). Pressure half-time was affected by heart rate, diastolic filling period, left ventricular fractional shortening and presence of atrial fibrillation (P < 0.001). Thus, using the standard continuity equation to determine the orifice area of the Bjork-Shiley prosthesis in the mitral position provides improved assessment compared with the pressure half-time method.

Adolescent↗
PubMed1994

Renal cell carcinoma developing in the pediatric recipient of an adult cadaveric donor kidney.

Renal cell carcinoma is an uncommon renal tumor in children, comprising between 1.8% and 6.3% of all malignant renal tumors of childhood (whereas renal cell carcinoma is the commonest renal tumor in adults). We describe a 15-year-old girl with chronic renal failure secondary to renal dysplasia and branchio-oto-renal syndrome, who received a cadaveric renal transplant at 8 years of age from a 25-year-old male donor. She developed severe chronic rejection 4 years after the transplant. A transplant nephrectomy was performed because of persistent gross hematuria. Histopathology of this graft showed chronic severe rejection and papillary necrosis. A fortuitous finding was a 1.5-cm renal cell carcinoma at one of the poles. We suggest that tumors which occur more commonly in adults and less commonly in children must be considered in children receiving adult organ transplants.

Adolescent↗
PubMed1994

Improvement of endocardial border delineation in suboptimal stress-echocardiograms using the new left heart contrast agent SH U 508 A.

Recent studies have shown that the saccharide based echocardiographic contrast agent SH U 508 A opacifies the left ventricle after i.v. injection, thus possibly improving endocardial border definition. This study was performed to determine whether SH U 508 A can enhance the wall motion analysis in suboptimal echocardiographic images at rest and following pharmacological stress. Ten male patients (mean 58 years) exhibiting > or = 30% endocardial border dropout were examined prior to a diagnostic left heart catheterization. Five patients were stressed with Dobutamine, 5 with Dipyridamole. The wall motion was assessed visually (qualitatively) as well as computer-aided (quantitatively). The concordance between left ventricular angiography as 'gold standard' and resting echocardiography regarding the wall motion analysis was significantly improved from 64.5% to 90.3% following the injection of SH U 508 A (p < 0.05). A delineation score (0 = not delineated, 1 = delineated) of 12 individual wall segments was used. The mean delineation score at baseline was 6.1 +/- 1.4 at rest and 6.6 +/- 1.9 during stress. SH U 508 A significantly (p < 0.01) increased the score to 9.6 +/- 1.9 and 10.3 +/- 1.7, respectively. The intraobserver variability for assessing the delineation score was significantly (p < 0.04) improved by SH U 508 A. SH U 508 A, however, did not improve the quantitative assessment of the left ventricular function. Only 40% of the patients could be analyzed following SH U 508 A injection. No severe adverse reactions were seen. SH U 508 A led to a significant, clinically important, improvement in the interpretation of stress echocardiograms in patients with inconclusive routine echocardiograms.

Adult↗