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Biomedical subjects

R K Sharma

Publications and source records attributed to R K Sharma.

At least 595 records · Page 33Linked to original sources

The effect of follicular fluid reactive oxygen species on the outcome of in vitro fertilization.

OBJECTIVE: To examine the presence of reactive oxygen species (ROS) in the follicular fluid of women undergoing in vitro fertilization (IVF) and identify its role in pregnancy outcome. STUDY DESIGN: In this prospective study, ROS and total antioxidant capacity (TAC) levels were measured by the chemiluminescence method in the follicular fluid of 53 women. Age, number of oocytes recovered, percentage of oocytes fertilized, ROS and TAC levels were compared in women who did and did not become pregnant. RESULTS: Patients who become pregnant had significantly higher log-transformed ROS levels (1.01 +/- 0.14, P = 0.031 than those who did not (0.69 +/- 0.08). Women with endometriosis or male factor infertility who became pregnant had significantly higher ROS levels (1.44 +/- 0.23 and 1.31 +/- 0.19) than those who did not (0.60 +/- 0.17 and 0.67 +/- 0.16; P < .006 and P < .01). CONCLUSION: Follicular fluid ROS, at low concentrations, may be a potential marker for predicting success in IVF patients.

Age Factors↗

Effect of swim-up sperm washing and subsequent capacitation on acrosome status and functional membrane integrity of normal sperm.

OBJECTIVE: Sperm preparation techniques select sperm population with improved sperm motion characteristics. We sought to determine whether the swim-up technique selects spermatozoa with the ability to undergo hypoosmotic swelling, and how swim-up and subsequent capacitation affect the acrosome reaction rate. METHODS: Semen specimens from 15 normal donors were divided into unprocessed, swim-up, and capacitated groups, and sperm motion characteristics, ability to undergo hypoosmotic swelling, and acrosome reaction rate were measured. RESULTS: Sperm motility, viability, and all motion characteristics (except linearity) were significantly increased in both swim-up and capacitated specimens. The ability to respond to hypoosmotic swelling was significantly higher in the spermatozoa isolated by swim-up. The percentage of acrosome-reacted spermatozoa remained unchanged in both unprocessed and swim-up groups, but was significantly higher in the capacitated group. CONCLUSIONS: Swim-up isolates sperm with greater ability to undergo hypoosmotic swelling, but does not change the acrosome reaction rate. In vitro capacitation of spermatozoa selected by swim-up enhances the acrosome reaction rate.

Acrosome↗

Oxidative stress in normospermic men undergoing infertility evaluation.

The purpose of this study was to determine whether normospermic infertile men have high seminal oxidative stress, using 3 measures of oxidative stress: reactive oxygen species (ROS), total antioxidant capacity (TAC), and a composite ROS-TAC score. Forty-three normospermic men without leukocytospermia and 19 healthy donors who came to our infertility clinic were included. Patients were categorized into 3 groups: group I, varicocele and no female factor (n = 16); group II, positive female factor (n = 16); and group III, idiopathic infertility (n = 11). In addition, 52 treated male factor patients and 19 donors were included as reference groups. We measured seminal ROS, TAC, and the ROS-TAC score in the patient groups and the controls. Normospermic infertile patients as a group had higher ROS levels (mean log [ROS + 1] 1.76 +/- 0.13) compared with controls (1.39 +/- 0.16; P = .03). Patients in the idiopathic subgroup had significantly higher ROS levels (2.29 +/- 0.25; P = .004) than controls. Normospermic infertile patients as a group not only had reduced TAC levels (970.18 +/- 73.95 Trolox equivalents), but each subgroup also had significantly lower TAC than controls (1650.93 +/- 95.87; P < .003). The ROS-TAC scores in all normospermic infertile patients as a group (35.7 +/- 1.8) as well as in each subgroup was significantly reduced compared with the ROS-TAC levels in the controls (50.0 +/- 2.1; P < .005). We conclude that oxidative stress is associated with male factor infertility. The presence of oxidative stress in infertile normospermic men may explain previously unexplained cases of infertility otherwise attributed to female factors.

Humans↗

Relationship between seminal white blood cell counts and oxidative stress in men treated at an infertility clinic.

In semen, granulocytes are major producers of reactive oxygen species (ROS), which can damage sperm. The diagnosis of leukocytospermia is usually based on the World Health Organization (WHO) definition of 1 x 10(6) white blood cells per milliliter, but controversy remains over the minimum leukocyte level that impairs fertility. The goals of this study were to clarity the relationship between leukocyte count and oxidative stress and to establish the minimum leukocyte count associated with oxidative stress. To do so, we compared oxidative stress in semen samples with different leukocyte counts (by the Endtz test) after a simple wash-and-resuspend procedure and determined the correlation between leukocyte counts and oxidative stress (expressed as ROS-TAC score, a composite score calculated from ROS levels and total antioxidant capacity (TAC), both measured with chemiluminescence assays). ROS-TAC decreases as oxidative stress rises. We compared specimens from 271 men attending an infertility clinic and 28 healthy controls. About 9% of patients had WHO-defined leukocytospermia and an additional 16% had some leukocytes. Samples with no seminal leukocytes had significantly lower ROS levels and significantly higher ROS-TAC scores than samples with any seminal leukocytes, even very low levels. Oxidative stress was correlated with rising white blood cell (WBC) count (r = .39; P < .001). Receiver operating characteristics curves showed that ROS-TAC score would be fairly accurate at distinguishing between patients with any leukocytes and those with no leukocytes (area under the curve, 75%). In conclusion, oxidative stress occurs even in patients with very low seminal WBC counts (between 0 and 1 x 10(6)/mL) and rises with an increase in WBC count. Therefore, we are unable to determine a safe minimum WBC count; the presence of any WBCs is associated with oxidative stress and may therefore impair fertility. Complete removal of WBCs from semen samples used for assisted reproduction may help reduce oxidative stress.

Area Under Curve↗

Tension-free open mesh repair of ventral hernias--Stoppa's technique.

Tension-free prosthetic mesh repair of giant, complex, or recurrent ventral hernias in the form of a modified Stoppa technique has been used in 60 cases. Complication rate has been comparable with other such studies. In obese patients with a pendulous anterior abdominal wall, limited panniculectomy was carried out while repairing the hernia through a low transverse abdominal incision. None of the patients required a progressive preoperative pneumoperitoneum. The incidence of wound infection was 5%. One patient had a wound hematoma that required evacuation; minor wound complications occurred in 11% cases. The hospital stay ranged from 1 to 6 weeks (mean, 10.3 days). One case required readmission for resuturing of the wound. None of the cases required removal of the mesh. There was no recurrence at follow-up (mean, 26 months) in 80% of the cases. This technique is an excellent but somewhat tedious procedure.

Adult↗

Effect of human gamma interferon on mice testis: a quantitative analysis of the spermatogenic cells.

Effect of Human Gamma Interferon (Hu-IFN-gamma) on the testicular histology was studied in mice. Male mice were administered Hu-IFN-gamma intratesticularly at the doses of 2, 10 and 20 micrograms/testis in a volume of 1.0 microliter isotonic normal saline. Contralateral testis served as control and was administered same amount of vehicle. All the animals were sacrificed 7 days after drug administration. Body weight and the weights of testis and epididymis were not affected by IFN treatment nor was there any effect of the drug on the motility of the vas deferens spermatozoa. Low dose of IFN (2 micrograms) did not have significant effect on the histoarchitecture of the testis and various spermatogenic elements, a progressive damage was however observed with the increasing doses of IFN. Pronounced deleterious effect of IFN on the testis leading to desquamation of the germinal epithelium, reduction in the germinal cell height and tubular diameter was observed with 20 micrograms dose. Quantitative studies on seminiferous epithelium showed a significant decrease in the number of Sertoli cells, stage-7 spermatids and stage-16 spermatozoa. The ratios of resting type spermatocyte: type A spermatogonia and stage-7 spermatids: pachytene spermatocyte was also reduced. The ratios of pachytene spermatocyte: resting spermatocyte and stage-16 spermatozoa: stage-7 spermatids were however not affected by IFN treatment. In another experiment IFN was administered (2 micrograms/day) subcutaneously to male mice for 30 days. No effect of drug treatment on body weight, organ weight, sperm motility and histology (including morphometry) of the testis was observed. Our data suggest that IFN action at testis may be associated with the antiproliferative effect of interferon.

Animals↗

Anti-insulin antibodies and retinopathy in juvenile onset type-1 diabetes.

Juvenile diabetics have severe loss of beta cell function and require replacement therapy with insulin. Insulin antigenicity can produce anti-insulin antibodies resulting in allergic reactions and insulin resistance. The role of insulin-anti-insulin antibody complexes in the development and progress of chronic diabetic complications like microangiopathy is not very clear. In the present study, there was statistically a significant trend of higher insulin antibody binding levels in IDDM patients who developed retinopathy. Though there was a trend of higher insulin antibody in IDDM patients with retinopathy, there was no association between insulin antibody and HLA antigen which some authors have reported.

Diabetes Mellitus, Type 1↗

Effect of sulphapyridine on male fertility in the rat.

Male rats administered sulphapyridine (60, 120 and 250 mg/kg) for 60 days demonstrated no change in body weight and testicular weight. However, there was a decrease in the weight of the epididymis. Motility and sperm reserves were reduced and were evident from fewer implantation sites and number of pregnancies. Furthermore, sulphapyridine did not show any effect on the histoarchitecture of the testis or epididymis. Serum levels of testosterone in the treated rats were comparable to their respective controls. Morphological abnormalities as revealed by scanning electron microscopic studies clearly demonstrated the detrimental effects of the drug.

Administration, Oral↗

Spermatogenic events in rat and mice following intratesticular administration of optical isomers of gossypol.

Male rats and mice were administered racemic and dextrorotatory gossypol intratesticularly at the dose of 200 micrograms/testis. In a separate experiment, 100 micrograms of dextrorotatory and levorotatory gossypol was administered to male mice. Animals were sacrificed 72 hours after drug treatment. In another experiment, mice were sacrificed 3, 10, 20, 30 and 60 days after racemic gossypol (200 micrograms/testis) administration. Marked degenerative changes in rat and mice tests were observed in the animals receiving racemic gossypol. Dextrorotatory gossypol had less pronounced effect, both in rat and mice. Stage 7 and 16 spermatids were most susceptible to the deleterious effects of racemic gossypol. In mice, 57.52% and 85.40% decrease in stage 7 and 16 spermatids were observed 72 hrs after drug administration. A progressive recovery was observed after drug treatment; the damage (stage 7 & 16) was reduced to 7.92% and 21.30% after 60 days. Histopathological changes in mice testis following 100 micrograms of levorotatory gossypol were distinctly different from those of the dextrorotatory (100 micrograms/testis) gossypol. On the basis of observations made by us, it can be suggested that mice equally respond to the antifertility effect of gossypol following intratesticular administration. The dextrorotatory gossypol, both in rat and mice, had less pronounced effect on the histoarchitecture of the testis in comparison to racemic and levorotatory gossypol. Our observations further suggest that this animal model provides meaningful information on the mechanism of action of gossypol, and recovery of spermatogenesis is possible after termination of drug treatment.

Animals↗

The influence of lactation on L-proline absorption from small intestine in the albino rat.

Intestinal absorption of L-proline was studied in control and lactating rats from jejunum and ileum by in vivo method and presented per unit dry weight and per unit length of the respective segment. L-proline absorption was found to be significantly reduced in lactating animals as compared to the virgin controls. The results were discussed in light of serosal to mucosal ratio. By in vitro method also jejunal and ileal uptake of L-proline were found to be significantly reduced in lactating animals as compared to the virgin controls.

Animals↗

Hypocholesterolaemic effects of dietary fibre.

Role of dietary fibre in lowering serum cholesterol has been studied in mongrel dogs. Pectin, wheat bra, guar gum and Isabghol were fed with standard diet. No statistically significant changes were found in serum cholesterol levels in any groug (P greater than .05) after one week. Later by 15th day, pectin reduced serum cholesterol significantly i.e. 12.4% (P less than .02). However, in groups being fed other forms of fibre the levels of serum cholesterol were reduced by 3.8% to 7.0

Animals↗

Effect of dietary fibre on oral glucose tolerance test.

Role of dietary fibre in lowering blood sugar levels has been studied in mongrel dogs. Pectin, wheat bran, guargum and Isabghol were fed with standard diet. Blood sugar levels were almost the same on 7th day (P less than .05). However, after 15 days pectin reduced blood sugar levels significantly (P less than .05), while other dietary fibre could not bring significant effect on blood sugar levels (P less than .05).

Animals↗

Forecasting need and demand for home health care: a selective review.

THREE MODELS FOR FORECASTING HOME HEALTH CARE (HHC) NEEDS ARE ANALYZED: HSA/SP model (Health Systems Agency of Southwestern Pennsylvania); Florida model (Florida State Department of Health and Rehabilitative Services); and Rhode Island model (Rhode Island Department of Community Affairs). A utilization approach to forecasting is also presented.In the HSA/SP and Florida models, need for HHC is based on a certain proportion of (a) hospital admissions and (b) patients entering HHC from other sources. The major advantage of these models is that they are relatively easy to use and explain; their major weaknesses are an imprecise definition of need and an incomplete model specification.The Rhode Island approach defines need for HHC in terms of the health status of the population as measured by chronic activity limitations. The major strengths of this approach are its explicit assumptions and its emphasis on consumer needs. The major drawback is that it requires considerable local area data.The utilization approach is based on extrapolation from observed utilization experience of the target population. Its main limitation is that it is based on current market imperfections; its major advantage is that it exposes existing deficiencies in HHC.The author concludes that each approach should be tested empirically in order to refine it, and that need and demand approaches be used jointly in the planning process.

Aged↗