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Biomedical subjects

R Sanchez

Publications and source records attributed to R Sanchez.

At least 127 records · Page 7Linked to original sources
PubMed1991

Induction of the acrosome reaction in sperm by exposure to low temperature increases their rate of fusion with zona-free hamster oocytes.

The fusion rate of human sperm with zona-free hamster ova was investigated after induction of the acrosome reaction by exposure to a low temperature (4 degrees C). Sperm were collected from 14 patients, and selected by the 'swim-up' method. The sperm were incubated for 24 h at either room temperature (control group) or at 4 degrees C (low temperature group), followed by additional incubation at 37 degrees C for 3 h. The mean sperm penetration rate, number of swollen sperm heads as well as the number of sperm attached to the oocyte increased significantly after exposing sperm to low temperature. The sperm penetration rate showed a significant correlation (Spearman test, r = 0.572, n = 28, P less than 0.0035) with the acrosome reaction in the low temperature group. These results were associated with an increase in the rate of penetration of hamster ova observed in this study, presumably due to the increase in induction of the acrosome reaction by low temperature. Incubation of sperm at low temperature might be useful in the evaluation of so-called false negative results in the zona-free hamster test.

Acrosome↗
PubMed1991

Phase I clinical trial with floxuridine and high-dose continuous infusion of leucovorin calcium.

Sixty-two patients with metastatic disease were treated with continuous infusion folinic acid (leucovorin calcium; Lv) and 2-deoxy-5-fluorouridine (floxuridine; FUDR). Lv was given by constant intravenous (IV) infusion at 500 mg/m2/d, days 1 to 6, while FUDR was given by IV push, days 2 to 6, at 3:00 PM daily with doses ranging from 294 to 1,214 mg/m2/d. This program was well tolerated with dose-limiting toxicities of diarrhea and stomatitis, while hematologic toxicity was minimal. Eighty-two percent of the assessable patients (46 of 56) had failed at least one chemotherapy regimen. One complete remission lasting 9 months and 10 partial remissions ranging from 5 to 10 months were observed in this heavily pretreated patient population for an overall response rate of 20%. These data suggest that the combination therapy with Lv and FUDR may have clinical use. Because of differing patient sensitivity to this drug combination, the recommended dose of FUDR for the initial therapy cycle is 500 mg/m2/d, days 2 to 6, with subsequent escalation to 900 mg/m2/d in those patients without extreme sensitivity. Phase II studies are now in progress with these doses.

Adult↗
PubMed1991

Interventional radiology in gallstone disease.

Interventional radiologic techniques for the treatment of gallstone disease are becoming more widely available. Percutaneous cholecystostomy [corrected] can be lifesaving in critically ill elderly patients who have acute cholecystitis. Contact dissolution of stones with methyl tert-butyl ether and percutaneous extraction (with or without fragmentation) of calculi are treatment options in patients who are at high risk for surgery or who do not desire an operation. With increasing use of intracorporeal gallstone lithotripsy techniques in the gallbladder and bile ducts, combined fluoroscopic and direct visualization during percutaneous procedures is becoming more important. Percutaneous chemical ablation of the gallbladder offers a potential solution to the problem of gallstone recurrence.

Acute Disease↗
PubMed1991

Techniques and clinical utility for percutaneous cholecystostomy.

Therapeutic gallbladder procedures offer new options for treatment of gallbladder disease. These procedures may be life-saving, may be easier than other available techniques, or may merely provide an alternative form of therapy. Further use of these techniques will likely result in improvements in PC, as well as providing an ongoing definition of the role of these percutaneous procedures.

Cholangiography↗
PubMed1991

Measurement of central venous pressure after open heart surgery and effect of positive end expiratory pressure.

Central venous pressure (CVP) recorded on electronic equipment (E-CVP) is compared with CVP measured by water column (W-CVP) in 50 patients after coronary bypass surgery without prior pulmonary symptoms. We find a statistically significant, but clinically insignificant, difference between E-CVP and W-CVP. Treatment with 10 cm H2O positive end expiratory pressure (PEEP) causes a significant rise in CVP by increasing intrathoracic pressure, but as changes in CVP rather than a given value are of greater importance in the daily clinical situation, we do not consider it clinically important to interrupt treatment with PEEP in as much as only small changes in CVP are induced after application of PEEP.

Blood Pressure Determination↗
PubMed1990

An analysis of the validity of the three-mile run as a field test of aerobic capacity in college males.

The purpose of the present investigation was to examine the concurrent and construct validity of the three-mile (4.83 km) run as a field test of aerobic capacity. Subjects included 109 college-aged males whose three-mile run time (M = 1310.31 +/- 184.48 s) was measured. Fifty of the subjects were given a maximal treadmill stress test, and their peak oxygen consumption (VO2peak) (M = 54.23 +/- 7.08 ml.kg-1.min-1) was measured. The three-mile run was conducted on an outdoor 0.25 mile (0.425 km) track, and split times were recorded each 110 yds (100.32 m) for the first and last laps and total time was recorded for laps 2 through 11. The correlation coefficient between the run time and VO2peak was -.58, indicating only moderate concurrent validity for the run as a field test for aerobic capacity. A factor analysis conducted on the split time data revealed a three-factor structure of a stable pace phase, an initial sprint, and a final sprint with the stable pace factor accounting for most of the common factor variance (69%). The three-mile run time was used to discriminate successfully between two known groups of subjects in aerobic capacity. These data provide a degree of support for the construct validity of the three-mile run as a field test of aerobic capacity.

Adult↗
PubMed1990

Misplacement of subclavian venous catheters: importance of head position and choice of puncture site.

We have investigated the frequency of misplacement of subclavian catheters in 200 consecutive patients admitted to the Intensive Care Unit. The patients were allocated randomly to an attempt at infraclavicular cannulation of the right or left subclavian vein with the head turned either towards or away from the selected side, giving four groups. Catheterization was successful in 185 (92.5%) patients. Misplacement into the internal jugular vein occurred in 10 (5.4%) patients. No statistically significant difference (P less than 0.05) was demonstrated between the four groups.

Adult↗
PubMed1990

Comparison of induction with and first hour of recovery from brief propofol and methohexital anesthesia.

Anesthesia and recovery during the first hour after propofol and methohexital anesthesia for termination of pregnancy, lasting about 12 min, were compared, the latter in a double-blind manner by means of psychomotor tests (coin counting and continuous auditory reaction time). Muscle movements and hiccups were seen significantly more frequently during methohexital inductions. No differences were seen regarding pain at the site of injection or apnea between the groups. At 15 min after the last dose of anesthetic, recovery after methohexital was ahead of that after propofol, but after 1 h, psychomotor performance was better in the propofol group. Side-effects during recovery were few, and incidences did not differ significantly. Although the difference in reaction time test was significant, it was hardly large enough to be of any clinical importance. Both drugs are useful for brief outpatient anesthesia, but smoother induction gives propofol an edge over methohexital.

Abortion, Induced↗
PubMed1990

Comparison of crotamiton 10% cream (Eurax) and permethrin 5% cream (Elimite) for the treatment of scabies in children.

Permethrin 5% cream (Elimite) was approved as a treatment for scabies by the U.S. Food and Drug Administration in September 1989. In a double-blinded, randomized study, it was compared with crotamiton 10% cream (Eurax) for the treatment of scabies in children 2 months to 5 years of age. Two weeks after a single overnight treatment, 14 (30%) of 47 children were cured with permethrin 5% cream, in contrast to only 6 of 47 (13%) of subjects treated with Eurax. Four weeks after treatment the figures were 89% and 60% cured for the two agents, respectively. In 10 of the 19 patients whose treatment failed, the condition became worse after therapy. The difference in efficacy in favor of permethrin was significant (P = 0.002). That agent also demonstrated greater effectiveness in reducing pruritus and secondary bacterial infections. Elimite offers a safe, efficacious, and cosmetically elegant alternative to Eurax in the treatment of scabies in children.

Administration, Topical↗
PubMed1990

Radiologic features of cerebral vasospasm.

Advances in neuroradiologic methods that allow greater understanding of vasospasm are described. The authors review the role of angiography in the evaluation of vasospasm and subarachnoid hemorrhage. Computed tomography has proved to be the most valuable diagnostic technique for the prediction of vasospasm, and the authors describe relevant investigations and detail clinical effectiveness.

Cerebral Angiography↗
PubMed1989

Efficacy and safety of cilazapril in elderly patients with essential hypertension. A multicenter study.

The efficacy and safety of cilazapril monotherapy was evaluated in a multicenter, open-label, ascending-dose titration study in 83 elderly essential hypertensive patients. After a four-week, single-blind, placebo run-in period, patients received 1 mg of cilazapril once daily for the first four weeks. This dose was then increased to 2.5 mg once daily for the next four weeks for patients whose pre-dose sitting diastolic blood pressure was above 90 mm Hg. Similarly, at Week 8 the dose was increased in such patients from 1 to 2.5 mg or from 2.5 to 5 mg once daily. A 12-hour blood pressure profile was performed on the first day of active treatment and of each dose increase. Mean decrease of sitting diastolic blood pressure from baseline (102.7 +/- 0.4 mm Hg) at Week 12 was 13.3 +/- 1.1 mm Hg (p less than 0.001). Seventy-five percent of patients had a decrease of 10 mm Hg or more from baseline sitting diastolic blood pressure, and in 60 percent sitting diastolic blood pressure normalized. Unexpectedly large decreases of blood pressure after the first dose were seen only in three patients and none had clinical symptoms. Fourteen patients (16.9 percent) reported adverse events, but most of these were judged unlikely to be related to therapy. Four patients with predisposing underlying diseases experienced potentially serious adverse events (angina pectoris, myocardial infarction, arrhythmia, and blood pressure elevation) whose relationship to therapy was judged remote or only possible. There was no particular pattern of changes in laboratory values. The results indicate that cilazapril is an effective, safe, and well-tolerated antihypertensive drug for the elderly.

Aged↗
PubMed1989

Partial biochemical and biological characterization of purified chicken growth hormone (cGH). Isolation of cGH charge variants and evidence that cGH is phosphorylated.

Chicken growth hormone (cGH) was purified from frozen pituitary glands obtained from recently sacrificed broilers. Glands were homogenized in a protease inhibitor solution (0.5 mM PMSF, 50 KIU/ml aprotinin, pH 7.2); extract was taken to pH 9.0 with calcium hydroxide and the supernatant was differentially precipitated with 20% (fraction A) and 50% (fraction B) ammonium sulfate. cGH (fraction B-DE-1) was obtained in pure form from fraction B after DEAE-cellulose chromatography at pH 8.6, with a yield of 2.9 mg/g tissue. Three charge variants of cGH (Rf = 0.23, 0.30, and 0.35) could be isolated by electroelution after semipreparative nondenaturing polyacrylamide gel electrophoresis of fraction B-DE-1. These charge variants showed the same apparent molecular weight (26,300 Da) by sodium dodecyl sulfate polyacrylamide gel electrophoresis under reducing conditions. Isoelectric focusing of fraction B-DE-1 revealed two major components (pI = 7.2 and 7.4) and four minor bands (pI = 6.2, 6.7, 7.1, and 7.5). It was found that fraction B-DE-1 contained a significant amount of esterified phosphate (1 nmol PO4/3.5 nmol protein) similar to that reported previously for ovine GH. The functional integrity of the cGH obtained here was characterized by two heterologous and one homologous bioassays. High activity was shown by fraction B-DE-1 in the tibia assay (1.76 UI/mg) and in the liver ornithine decarboxylase assay (sixfold over control), both made in hypophysectomized rats; and it also stimulated lipolysis (138 and 215% at 10 and 100 ng/ml, respectively) on chicken abdominal adipose tissue explants.

Animals↗
PubMed1989

Induction and recovery characteristics of propofol, thiopental and etomidate.

Propofol, thiopental and etomidate, with 20 patients in each group, were compared for anesthesia of short duration in women undergoing termination of pregnancy, with respect to: 1: pain on injection (equally often after propofol and etomidate, but more rarely after thiopental); 2: apnea following induction (no difference); 3: involuntary muscular movements more frequent after etomidate); 4: blood pressure (larger drop after propofol); 5: heart rate (greater increase after thiopental); 6: time to eye opening on command (longer after propofol); 7: Steward score on eye opening (no difference); 8: coin counting after 15, 30 and 60 min (performance better after propofol at 15 and 30 min, producing even shorter times than preoperatively at 60 min); 9: reaction time after 15, 30 and 60 min (performance better after propofol, producing even shorter times than preoperatively at 60 min. It is concluded that the faster recovery gives propofol an advantage over thiopental and etomidate in outpatient anesthesia.

Abortion, Induced↗