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Biomedical subjects

J Mitchell

Publications and source records attributed to J Mitchell.

At least 361 records · Page 20Linked to original sources
PubMed1983

Metkephamid and meperidine analgesia after episiotomy.

Metkephamid is an analog of methionine enkephalin. The efficacy, safety, and time course of analgesia with 70 or 140 mg metkephamid were compared with those of 100 mg meperidine and placebo in 59 hospitalized women with severe postpartum episiotomy pain. There were two separate trials with single intramuscular doses and identical designs, including parallel groups, randomized blocks, and double-blind conditions. Using subjective reports as indexes of response, patients rated pain intensity, pain relief, and side effects at periodic interviews for 6 hr. Almost all measures of summed and peak analgesia exhibited important differences among the three treatments in both trials. Metkephamid at the 140-mg dose was the most effective and meperidine, 100 mg, was next, whereas metkephamid, 70 mg, and placebo were least effective. Only metkephamid, 140 mg, and meperidine were measurably superior to placebo. Both treatments took effect within 30 min and peaked at 1 to 2 hr; with 140 mg metkephamid, maximum analgesia was sustained 6 hr, i.e., 2 hr longer than with meperidine. Metkephamid, 70 mg, could not be distinguished from placebo throughout its entire time course. Although dizziness was experienced with meperidine, the two metkephamid doses induced other side effects, including sensation of heavy limbs, dry mouth, eye redness, and nasal stuffiness. None were distressing. Our results suggest that 140 mg metkephamid compares favorably with 100 mg meperidine for analgesia after episiotomy, but it induces minor side effects more frequently.

Adolescent↗
PubMed1983

Codeine and aspirin analgesia in postpartum uterine cramps: qualitative aspects of quantitative assessments.

The analgesic response to codeine of patients with postpartum uterine-cramp pain has recently met with controversy. To readdress this question, we conducted a new study comparing codeine sulfate, 60 mg (N = 32) and 120 mg (N = 31), with aspirin, 650 mg (N = 34), and placebo (N = 32) in hospitalized women with moderate or severe postpartum uterine cramps treated with single oral doses in a parallel, stratified, randomized, double-blind trial. Subjective reports were used as indices of response, and patients rated pain intensity, pain relief, and side effects at periodic, uniformly conducted interviews for 6 hr. Most measures of analgesia exhibited important differences among the treatments. In patients with undifferentiated pain (N = 129) and in a subset of patients with pure uterine cramps (N = 56; i.e., no concomitant episiotomy), aspirin showed the greatest response, whereas codeine responses were equivocal with no evidence of a positive dose response. In contrast, in a subset of patients with mixed episiotomy-uterine pain (N = 73), 120 mg codeine showed good separation from placebo and compared favorably with aspirin. Codeine, 60 mg, showed a similar trend, and there was a strong suggestion of dose-dependent analgesia. Side effects were not remarkable except for dizziness and drowsiness after 120 mg codeine in all sets and subsets of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1983

Psychopharmacological treatment of anorexia nervosa and bulimia. Review and synthesis.

Recent reports have indicated that the incidence of anorexia nervosa and bulimia has increased over the last several years. Both of these syndromes present serious treatment challenges to clinicians and in an effort to deal more effectively with these disorders several pharmacological interventions have been attempted. This article reviews the range of pharmacological interventions used with anorexia nervosa and bulimia patients. The purpose of the review is to present our current knowledge regarding the efficacy of these medications and to offer methodological recommendations that will enhance future research efforts.

Adrenocorticotropic Hormone↗
PubMed1983

Trophoblast sampling by blind transcervical aspiration.

Blind transcervical aspiration for trophoblast was carried out on 137 patients undergoing elective termination of early pregnancies. Trophoblast was obtained from 45 patients (33%) usually at the first attempt. Collection was not necessarily more successful between 8 and 11 weeks of gestation. In only 13 patients (9%) was trophoblast collected without contamination by maternal tissue, or blood. Perforation of the amniotic sac in one patient (1%), bleeding either observed, or detected histologically (34%) and introduction of infection (4%) constitutes a real threat to fetal survival. Maternal serum alpha-fetoprotein estimation appears useful and may forewarn likelihood of fetal damage. Although transcervical aspiration should encounter ready acceptability as an out-patient procedure, modifications in the technique are essential before clinical application for detection of gene, or chromosome anomalies can be considered.

Biopsy, Needle↗
PubMed1983

Interferon as an in vitro modifier of immune responses induced by combined vaccine (DTP) in mice.

The ability of DTP (diphtheria, tetanus, pertussis) vaccine to stimulate IgG-plaque forming cells (PFC) in mice was markedly inhibited by human leukocyte and mouse fibroblast interferon (IF). This effect of IF was not dose-dependent. The maximum inhibitory effect of human IF was observed on Day 10 after the administration of the vaccine. The inhibition of IgM-PFC was more severe when human IF was used. Although IF abrogated the effect of DTP vaccine on IgG-PFC, at the same time it stimulated PFC in the control group of non-vaccinated animals. The administration of DTP vaccine decreased IgM-PFC on Day 5, the effect was enforced by the addition of both human and mouse IF. IF decreased IgM-PFC in the control group. Small and large doses of DTP suppressed the leukocyte adherance inhibition (LAI) on Day 5 after administration of the vaccine, the effect was not affected by addition of IF. The suppressive effect of DTP was lost on Day 10 when addition of IF increased the percent of LAI in all experimental groups. Thus IF appears to interfere with the effect of DTP and selectively modulate the different immune responses.

Animals↗
PubMed1983

Increased urinary vasopressin excretion in the DOCA-hypertensive pig.

A possible role for vasopressin in the development and/or maintenance of DOCA hypertension in pigs was studied. In control pigs mean arterial blood pressure (MABP), plasma lysine vasopressin (LVP) concentration, the 24-h urinary excretion of LVP (ULVPV) and plasma renin activity (PRA) did not change throughout the 30 days of the experiment. In DOCA-treated pigs MABP began to increase from the initial level of 95 +/- 2 mm Hg within 5 days and reached a level of 127 +/- 3 mm Hg between days 20-30 (P less than 0.01). At this time in the DOCA treated pigs, ULVPV increased threefold (P less than 0.05), although PLVP was unchanged and PRA was reduced to almost zero. After 30 days the pigs were fed a low sodium diet. This was without effect on MABP, PLVP and ULVPV in control pigs. However, in the DOCA-treated pigs, MABP fell from 133 +/- 2 to 112 +/- 6 mm Hg, accompanied by a 60% fall in ULVPV. PLVP was unchanged. Thus in DOCA-treated pigs, LVP appears not to be involved in the development of hypertension, but may be involved in its maintenance.

Animals↗
PubMed1983

Differential effects of DOCA on renal and gastrointestinal handling of sodium and potassium in pigs.

Young, male pigs eating standard pig chow, ad libitum, received approximately 170 mEq Na and 290 mEq K per day. Electrolyte intake, urinary and fecal electrolyte output, and plasma electrolyte levels were determined daily in 12 deoxycorticosterone acetate (DOCA)-treated pigs and in 6 control pigs. Daily Na and K balances (dietary intake - urinary + fecal output) were calculated. DOCA caused a reduction in urinary Na output from 1.53 mEq/kg/day to 0.57 mEq/kg/day during the first 48 hr following implantation. Escape from the renal sodium retaining effect of DOCA was complete within 3 days, with urinary Na output returning to pre-DOCA levels. Fecal Na output decreased from 0.65 mEq/kg/day during the preimplant period to 0.13 mEq/kg/day during the postimplant period. No escape from GI Na retention occurred by Day 15. Plasma Na rose to significantly higher levels by Day 15. Sodium balance was significantly elevated in DOCA-treated pigs for that first 48 hr postimplant. Urinary K output decreased from 3.50 mEq/kg/day to 1.74 mEq/kg/day during the first 2 days, but returned toward preimplant levels by Day 4. Fecal K output was increased for the first week, and thereafter returned to preimplant levels. Plasma K fell from 3.9 to 2.9 mEq/liter by Day 15. Potassium balance fell slightly in both experimental and control animals. No significant differences in potassium balance were present between the two groups. The control pigs showed no significant changes in plasma electrolyte concentration or in electrolyte balance. It is concluded that DOCA has differential effects on renal and gastrointestinal handling of electrolytes and that DOCA may induce an intracellular shift of potassium in pigs.

Animals↗
PubMed1983

Proliferation of human malignant hematopoietic cells in immunodeficient mice: suppression by antibody to pluripotent K-562 leukemia cells involves direct cytolysis and effector cells.

Six human hematopoetic cell lines were successfully heterotransplanted into athymic (nude) and asplenic-athymic (lasat) neonatal mice. The tumors arising from leukemia and lymphoma cells could then be serially transplanted into adult nude mice. Seven days after the fourth serial mouse passage, each mouse was treated with goat immune gamma globulin against K-562 cells. One control group was treated similarly, but with nonimmune (normal) gamma globulin, while another control group was not treated. The goat gamma globulin was not toxic for nude and lasat mice, and the immune, but not the normal, gamma globulin suppressed local subcutaneous growth of myelosarcomas, lymphosarcomas, and Burkitt lymphoma cells. On the other hand, the growth of lung, breast, and prostatic carcinomas and a melanoma of human origin were not altered by the immune gamma globulin. Since suppression of cell growth occurred equally well in decomplemented mice, a complement-mediated cytotoxicity apparently cannot be considered as responsible for the abrogation. The Fab fragment of the immunoglobulin did not suppress the growth of the myelosarcomas. We conclude that antibody suppression of the in vivo proliferation was specific for malignant hematopoietic cells and that the Fc portion of IgG is necessary for in vivo cytolysis of leukemia cells. The most probable mechanisms are direct antibody cytolysis and antibody-dependent macrophage-mediated cytotoxicity.

Adenocarcinoma↗
PubMed1983

The permeability of the capsule of autonomic ganglia to horseradish peroxidase.

Horseradish peroxidase (HRP) was applied to the capsules of various autonomic ganglia in vivo. The capsules of the inferior mesenteric ganglion and superior cervical ganglion of guinea-pigs and the inferior mesenteric ganglion of mice were readily penetrated by the enzyme. The capsule of the mouse superior cervical ganglion was apparently impermeable to HRP, while that of the guinea-pig lumbar sympathetic trunk was intermediate in permeability, being most readily penetrated by HRP around the blood vessels entering or leaving the ganglia. The results of retrograde transport experiments from the guinea-pig inferior mesenteric ganglion to spinal ganglia are considered in the light of the ready permeability of its capsule.

Animals↗
PubMed1982

Characterization of the rabbit renal receptor for native parathyroid hormone employing a radioligand purified by reversed-phase liquid chromatography.

Iodinated native bovine parathyroid hormone (bPTH(1-84)) was separated from uniodinated hormone by reversed-phase liquid chromatography techniques after lactoperoxidase labeling. Analysis of iodinated residues after enzymatic digestion indicated that the major labeled product was largely monoiodinated on the sole tyrosine residue. This material retained full bioactivity in an in vitro renal adenylate cyclase assay. Binding of 125I-bPTH(1-84) to rabbit renal membranes at 4 degrees C was proportional to membrane protein concentration and was saturable and dissociable. Radioligand binding was inhibited by concentrations of unlabeled bPTH(1-84) required to stimulate adenylate cyclase in the same membrane preparation but was not inhibited by non-PTH peptides other than adrenocorticotropin at high concentrations (greater than 10 microM). Synthetic NH2-terminal analogues of bPTH(1-84) all elicited approximately equivalent inhibition of radioligand binding which was, however, less potent than unlabeled bPTH(1-84), suggesting a role for the carboxyl region of the molecule in the interaction of bPTH(1-84) with its receptor. Activity of the NH2-terminal agonists was similar to bPTH(1-84) in stimulating adenylate cyclase. Although substitution in sequence position one, of serine in human PTH(1-34) for alanine in bPTH(1-34), reduced activity in the adenylate cyclase assay, inhibition of 125I-bPTH(1-84) binding by both peptides and by an analogue of bPTH(3-34) was equivalent, consistent with a minimal contribution of the first 2 residues for receptor binding of the NH2-terminal region of PTH. The results illustrate the utility of the radiolabeled preparation of native bPTH we have developed and emphasize the importance of probing the PTH receptor with an intact hormone to maximize information concerning the mechanism of PTH action.

Animals↗
PubMed1982

The development of fetal acidosis in the presence of an abnormal fetal heart rate tracing. I. The average for gestational age fetus.

An abnormal fetal heart rate (FHR) tracing is a sensitive indicator of positivity that disease exists, but the intrinsic predictive value of such a tracing is disappointingly low because of the large number of false positive results. Abnormal FHR tracings, defined as those having a persistent quantitative score of 4 or less, were measured against time and outcome. A baseline fetal scalp blood sample was taken. Twenty fetuses were acidotic at the first blood sample. There were 121 study cases, all of which were greater than 37 weeks' gestational age. All fetuses were average for gestational age. Amniotic fluid was clear, internal FHR tracings were initially normal, and the first pH was normal. A relative acidosis-free interval could be demonstrated during the first 90 to 100 minutes. Following this time period rapid cumulative acidosis was seen, which varied according to the FHR pattern observed. The P50 acidosis values for various patterns were late decelerations, 115 minutes; variable decelerations, 145 minutes; and flat line tracings, 185 minutes.

Acidosis↗