ABO incompatible renal transplantation: a qualitative analysis of native endothelial tissue ABO antigens after transplantation.
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ABO Blood-Group System↗
Biomedical subjects
M Morris
Publications and source records attributed to M Morris.
Profile of congenital cholesteatomas of the petrous apex.
Congenital cholesteatomas of the petrous apex are now frequently being approached by otologists. Involvement of the cerebello pontine angle by this lesion produces a myriad of signs and symptoms. Otological as well as neurosurgical literature is reviewed to achieve an overall understanding of the nature and behaviour of this uncommon but interesting lesion.
Bone Diseases↗
Re-treatment of patients with recurrent epithelial ovarian cancer with cisplatin-based chemotherapy.
Nineteen patients with recurrent epithelial ovarian cancer who had responded to initial cisplatin-based combination chemotherapy were re-treated with cisplatin-based therapy. The median disease-free interval, as measured from the last cycle of primary chemotherapy to the diagnosis of relapse, was 26.3 months (range 5-81 months). Eighteen of the 19 patients had measurable disease at the time of relapse. Nine patients had a clinical complete response to the cisplatin-based re-treatment, and nine patients had a partial response (surgically documented in one case). The overall response rate to secondary cisplatin-based chemotherapy was therefore 100% in patients with measurable disease. Toxicity of re-treatment was acceptable. The median progression-free survival, as measured from the diagnosis of relapse to the time of disease progression, was 10.6 months (range 4-24 months). The median survival from diagnosis of relapse was 19.3 months (range 5-39 months). At the time of analysis, three patients were alive without evidence of disease, four were alive with tumor, and 12 were dead of cancer. These data suggest that re-induction with cisplatin-based chemotherapy should be considered for patients who develop recurrent disease after favorable responses to primary cisplatin-based chemotherapy.
Adult↗
Total body photographs of dysplastic nevi.
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Dysplastic Nevus Syndrome↗
Release of substance P in the nucleus tractus solitarius measured by in vivo microdialysis: response to stimulation of the aortic depressor nerves in rabbit.
Substance P (SP) is found in high concentration in the nucleus tractus solitarius (NTS), and is a neurotransmitter candidate in primary baroreceptor afferents to the NTS. Release of SP in the medial NTS of halothane-anesthetized rabbits was measured by in vivo microdialysis. Bilateral electrical stimulation of the aortic depressor nerves (ADN) elicited a significant elevation in SP collected during the period following stimulation, while sham stimulation had no effect. Perfusion through the dialysis probe with a high-potassium (150 mM) solution caused a large increase in the level of SP collected, verifying the neural origin of this release. Possible explanations for the delay in increased release of SP include interaction with carotid afferents, diffusion time, or excitation of SP-containing inputs to the NTS originating elsewhere in the brain. This study demonstrates that SP release in the NTS is elevated by activation of baroreceptor afferents, supporting the hypothesis that SP plays a role in the central integration of cardiovascular control. Whether this release is from primary afferent terminals, or from another source, remains to be seen.
Animals↗
Adoption and genetic prediction for Huntington's disease.
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Adolescent↗
Analysis of T cell receptor beta chains in rat thymus, and rat C alpha and C beta sequences.
In development, T cells first express their alpha beta antigen receptors in the thymus, where they may undergo selection processes leading to major histocompatibility complex (MHC) restriction and tolerance. A high proportion of thymocytes are thought to fail this selection in some way and to be destined for intrathymic death. These cells are categorized as the "cortical type" since they constitute most of the cortical cells; they express both CD4 and CD8 antigens but only very low levels of MHC class I antigens. One suggested cause of thymocyte death is a failure to produce a functional alpha beta T cell receptor (Tcr) due to errors in the rearrangements of germline DNA, resulting in V regions being absent or incorrectly spliced to the other segments of the transcribed gene. We have sequenced from the C region through to the V region of 14 rat Tcr beta chain clones isolated from thymocyte cDNA libraries. Of the 14, 13 have complete and correct rearrangements, whereas one was expressed from an unrearranged gene. Most of these clones are likely to be derived from the cortical population, for Northern blot analysis showed that these cells and total thymocytes expressed similar amounts of beta chain mRNA. Furthermore, the RNA from cortical-type cells contained a very similar ratio of full-length to truncated beta chain mRNA as did activated thymocytes and mature T lymphocytes. The data imply that defective beta chain gene rearrangement is not a major cause of failure in the selection of thymocytes. The sequences of the rat Tcr alpha and beta chain constant regions are also reported.
Amino Acid Sequence↗
Physiological mechanism of digital vasoconstriction training.
Recent work in our laboratory has shown that vasodilation produced during temperature biofeedback training is mediated through a nonneural, beta-adrenergic mechanism. Here we sought to determine if the effects of feedback training for vasoconstriction are produced through a neural or nonneural pathway and whether other measures of physiological activity are correlated with these changes. Nine normal subjects received temperature feedback vasoconstriction training in which feedback was delivered only during periods of successful performance. In a subsequent session, the nerves to one finger were blocked with a local anesthetic while finger blood flow was recorded from this and other fingers. Vasoconstriction occurred during feedback in the intact fingers but not in the nerve-blocked finger and was accompanied by increased skin conductance and heart rate. These data demonstrate that temperature feedback vasoconstriction training is mediated through an efferent, sympathetic nervous pathway. In contrast, temperature feedback vasodilation training is mediated through a nonneural, beta-adrenergic mechanism.
Adult↗
Effect of central hypertonic stimulation on plasma atrial natriuretic peptide and oxytocin in conscious rats.
The effect of the intracerebroventricular (i.c.v.) injection of hypertonic sodium chloride on plasma atrial natriuretic peptide (ANP) and oxytocin (OT) was evaluated in conscious freely moving rats. A hypertonic or isotonic NaCl solution was injected into the third ventricle. Blood pressure and heart rate were monitored and blood samples were collected. I.c.v. injection of the hypertonic solution resulted in a significant increase in mean arterial pressure (105.3 +/- 2.9 mmHg at time 0 to 124.2 +/- 4.4 mmHg at 5 min, P less than 0.01) and heart rate (350.0 +/- 25.0 bpm at time 0 to 420.8 +/- 13.6 bpm at 20 min, P less than 0.01). Plasma OT increased 4-fold over the basal values 5 min after the injection (4.5 +/- 1.1 to 20.1 +/- 3.2 pg/ml, P less than 0.01), while there was no significant change in plasma ANP (37.3 +/- 9.1 to 46.6 +/- 12.6 pg/ml, n.s.). The control injection produced no significant changes in any parameters. These results show that hemodynamic changes are not necessarily associated with alterations in plasma ANP. Furthermore they suggest that central osmoreceptors are not involved in the control of ANP secretion.
Animals↗
Efficient algorithms for molecular sequence analysis.
Efficient (linear time) algorithms are described for identifying global molecular sequence features allowing for errors including repeats, matches between sequences, dyad symmetry pairings, and other sequence patterns. A multiple sequence alignment algorithm is also described. Specific applications are given to hepatitis B viruses and the J5-C (J, joining; C, constant) region of the immunoglobulin kappa gene.
Algorithms↗
Coloration of breast fluid related to concentration of cholesterol, cholesterol epoxides, estrogen, and lipid peroxides.
The coloration of nipple aspirates of breast fluid from 2,343 women were compared with breast fluid concentrations of cholesterol. cholesterol epoxides, lipid peroxides, estrogens, and immunoglobulins. Darker-colored breast fluid had significantly higher mean concentrations of cholesterol, cholesterol epoxides, lipid peroxides, and estrogens than did lighter-colored fluids, whereas no relationship of coloration with immunoglobulin levels was found.
Breast↗
Algorithms for identifying local molecular sequence features.
Efficient algorithms are described for identifying local molecular sequence features including repeats, dyad symmetry pairings and aligned matches between sequences, while allowing for errors. Specific applications are given to the genomic sequences of the Epstein-Barr virus, Varicella-Zoster virus and the bacteriophages lambda and T7.
Algorithms↗
Effects of chronic sinoaortic denervation on central vasopressin and catecholamine systems.
The objective of this study was to determine whether chronic arterial baroreceptor deficit induces time-related changes in central vasopressin (AVP) and catecholamine systems. Groups of sinoaortic-denervated (SAD) and sham-operated (SO) rats were studied 1, 3, 4, 7, and 14 days after surgery. Supraoptic (SON), paraventricular (PVN) and arcuate (ARC) nuclei, median eminence (ME) region, and A1 region of medulla were obtained by micropunch from frozen brain sections and assayed for AVP, tyrosine hydroxylase (TH) activity, catecholamines, and their metabolites, dihydroxyphenylethyleneglycol (DOPEG) and 2,5-dihydroxyphenylacetic acid (DOPAC). AVP concentration in SON and PVN was increased in 1-day-SAD rats, reduced in 3- and 4-day-SAD rats, equal and above control values in 7- and 14-day-SAD rats, respectively. TH activity was increased in SON and reduced in ME and ARC of 1- and 7-day-SAD rats. In SON, DOPEG was increased, whereas in ME all catecholamines and DOPEG and DOPAC were reduced in 1-day-SAD rats. ME catecholamines returned toward control levels in 3- to 4-day-SAD rats. These studies show that the chronic absence of arterial baroreceptor input produces time-related, regionally specific central changes of vasopressin and regionally associated catecholamines.
3,4-Dihydroxyphenylacetic Acid↗
Baroreceptor influences on plasma atrial natriuretic peptide (ANP): sinoaortic denervation reduces basal levels and the response to an osmotic challenge.
The objective of these studies was to investigate baroreceptor/osmotic interactions by determining the effect of sinoaortic denervation (SAD) on the ANP response to a hypertonic saline challenge in conscious rats. A time course study showed that there was a rapid increase in plasma ANP in response to iv hypertonic saline. The peak effect was at 5 min, a 3-fold increase (P less than .01). Baroreceptor denervation produced significant decreases in basal ANP levels and osmotic induced release (P less than 0.01). Plasma ANP increased from 25 +/- 3.2 to 136.8 +/- 28 in the sham-operated rats and from 11.8 +/- 2.6 to 30.8 +/- 4.6 in the SAD. Plasma sodium was the same in the 2 groups, and there was no change in atrial ANP content. Blood pressure was elevated in the denervated animals; however, the pressor response to the hypertonic challenge was not different from the controls. These results suggest that the baroreceptor system may have important influences on cardiovascular/hormonal regulation.
Animals↗
[Variations in the plasma concentrations of atrial natriuretic factor and endogenous digitalis compounds during acute volume expansion in the conscious rat].
Atrial natriuretic peptide (ANP) and Na+ pump inhibitor (digitalis-like substance, DLS) have both been proposed to participate in body sodium and water homeostasis. Plasma levels and ANP and DLS have been reported to be increased in physiological or pathological states characterized by volume expansion. In order to investigate possible mutual relationships, their concentrations were measured in parallel during acute volume expansion by injection of 25 ml/kg isotonic NaCl (A) or blood (B) in the conscious rat. ANP was measured by radioimmunoassay and DLS by inhibition of renal Na+, K+-ATPase activity and digoxin-like immunoreactivity (DLI). Five minutes after injection, plasma ANP increased to reach 700 pg/ml (A, n = 21) or 1,500 pg/ml (B, n = 5) but the ability of plasma extracts to inhibit the renal Na+, K+-ATPase activity was unchanged (16.6 +/- 2.5 vs 16.9 +/- 2.0 p. 100, A, n = 8 and 6). Digoxin-like immunoreactivity was slightly lowered after NaCl injection from (74.4 +/- 6.2 to 65.4 +/- 5.1 pg/ml, n = 21) and unchanged after blood injection (79.0 +/- 3.4 vs 81.2 +/- 5.0 pg/ml, n = 5). Plasma ANP concentrations then decreased and had returned to preinjection values before 30 (A) or 90 (B) minutes, whereas the capacity of plasma to inhibit the Na+, K+-ATPase tended to increase (25.9 +/- 4.7 p. 100 at 3 hours after injection, n = 12 compared to 17.6 +/- 1.6 p. 100, n = 20) and DLI remains stable.(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
Cost-effectiveness of including cromolyn sodium in the treatment program for asthma: a retrospective, record-based study.
The treatment of chronic mild to moderately severe asthma is expensive for families and for society. Controlling the costs of asthma-related medications, physician visits, emergency room visits, and hospital admissions is therefore an important consideration. A retrospective, record-based study was undertaken to determine the costs of treating asthma in patients for whom cromolyn sodium was included in the routine treatment plan (n = 27) and those for whom treatment did not include cromolyn sodium (n = 26). Significant reductions in the number of emergency room visits and hospital admissions were obtained in patients who were treated with cromolyn sodium. The estimated average cost of emergency room visits was $33 a year for the patients given cromolyn sodium compared with $624 a year for patients in the comparison group. The estimated average cost of hospital admissions was reduced by $1,298 for the cromolyn sodium group compared with a $357 reduction for the comparison group. Computed for the entire course of treatment, the average (+/- SD) daily cost of medications for the comparison group was $0.84 +/- $0.37 versus $0.93 +/- $0.25 for the cromolyn sodium treatment group. Thus dramatic savings in costs of emergency room visits and hospitalizations when cromolyn sodium was included in therapy were effected at a small increase in the overall cost of medications. Analyzed visit by visit, the average daily cost of treatment that included cromolyn sodium decreased while that of the comparison group increased. We conclude that including cromolyn sodium in a regular anti-asthma regimen is a cost-effective and therapeutically effective treatment strategy.
Adrenal Cortex Hormones↗
Traveller health care: stopped in their tracks.
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Adolescent↗
Plasma neuropeptide Y concentration is increased after hemorrhage in conscious rats: relative contributions of sympathetic nerves and the adrenal medulla.
Most peripheral noradrenergic nerves have been shown to contain the coexisting peptide, neuropeptide Y (NPY). The aim of this study was to determine whether NPY is released together with catecholamines during activation of the sympathoadrenal system by hemorrhagic stress in conscious rats. Plasma NPY rose from a baseline value of 7.7 +/- 1.2 to 14.4 +/- 2.7 and 14.9 +/- 2.3 ng/ml (mean +/- SEM, n = 8) 10 and 30 min after hemorrhage, respectively. Plasma norepinephrine (NE) and epinephrine concentrations rose immediately after hemorrhage and at 30 min were increased twofold and ninefold, respectively. To determine the source of the increase in circulating NPY after hemorrhage, rats were subjected to adrenalectomy or to chemical sympathectomy with intravenous (i.v.) 6-hydroxydopamine (6-OHDA). 6-OHDA-treated rats had no significant increase in plasma NPY after hemorrhage, whereas adrenalectomized rats had an enhanced NPY response to hemorrhage. These results suggest that the sympathetic nerves make the major contribution to the increase in plasma NPY concentrations after activation of the sympathoadrenal system by hemorrhagic stress.
Adrenal Medulla↗