Showing papers by "University of Texas Medical Branch published in 1986"
Journal Article•
TL;DR: It can be concluded with some certainty that the healthStatus of Hispanics in the Southwest is much more similar to the health status of other whites than that of blacks although socioeconomically, the status of Hispanics is closer to that of Blacks.
Abstract: Recent reports in the literature on the health status of southwestern Hispanics, most of whom are Mexican Americans, are reviewed critically. The review is organized into the following sections: infant mortality, mortality at other ages, cardiovascular diseases, cancer, diabetes, other diseases, interview data on physical health, and mental health. Despite methodological limitations of much of the research, it can be concluded with some certainty that the health status of Hispanics in the Southwest is much more similar to the health status of other whites than that of blacks although socioeconomically, the status of Hispanics is closer to that of blacks. This observation is supported by evidence on such key health indicators as infant mortality, life-expectancy, mortality from cardiovascular diseases, mortality from major types of cancer, and measures of functional health. On other health indicators, such as diabetes and infectious and parasitic diseases, Hispanics appear to be clearly disadvantaged relative to other whites. Factors explaining the relative advantages or disadvantages of Hispanics include cultural practices, family supports, selective migration, diet, and genetic heritage. The recently completed Hispanic Health and Nutrition Examination Survey will go a long way to provide answers to many questions regarding the health of Hispanics in the Southwest or elsewhere.
1,014 citations
TL;DR: The procedure liberates neurons free of cellular debris and glial investments, allowing the formation of giga-ohm seals with patch clamp electrodes, and the characteristic morphology of neurons is maintained.
403 citations
TL;DR: It is suggested that HA and fibrin have both structural and regulatory functions at different times during the wound healing process, and it is predicted that HA controls the stability of the matrix by regulating the degradation offibrin.
371 citations
TL;DR: It is reported that the production of ACTH and endorphins by leukocytes is indeed induced by synthetic CRF10 and, in turn, suppressed by dexamethasone, suggesting that, as in pituitary cells, the pro-opiomelanocortin (POMC) gene may be expressed and similarly controlled in leukocyte.
Abstract: Corticotropin releasing factor induction of leukocyte-derived immunoreactive ACTH and endorphins
340 citations
TL;DR: The findings from the present study reveal that, although social support fails to modify the effects of a global stressful life events indicator, specific types of social support buffer the impact of Specific types of stressors (bereavement, crime, and social network crises).
Abstract: The purpose of this study was to examine whether social support buffers the deleterious effects of stressful life events on depressive symptoms among a random community sample of older adults. Previous research has provided contradictory conclusions regarding the stress buffering capacity of supportive social relations. The reason for these inconclusive findings may be traced in part to the failure of researchers to disaggregate their social support and stressful life event inventories. The findings from the present study reveal that, although social support fails to modify the effects of a global stressful life events indicator, specific types of social support buffer the impact of specific types of stressors (bereavement, crime, and social network crises).
328 citations
TL;DR: It is reported that, as expected, single cGMP-activated channel activity can be detected from an excised rod membrane patch in the absence of divalent cations, and a puzzle about the light-sensitive conductance is resolved by demonstrating that it is an aqueous pore rather than a carrier.
Abstract: The plasma membrane of retinal rod outer segments contains a cyclic GMP-activated conductance1–6 which appears to be the light-sensitive conductance involved in phototransduction7. Recently, it has been found that this conductance is partially blocked by Mg2+ (refs 3, 8, 9) and Ca2+ (refs 3, 4, 8–11) at physiological concentrations, thus possibly accounting for the absence of observable single-channel activity in excised membrane patches1,3,8 and for the unusually small apparent unit conductance deduced from noise measurements on intact cells4,10,12,13. We now report that, as expected from this idea, single cGMP-activated channel activity can be detected from an excised rod membrane patch in the absence of divalent cations. The most prominent unitary current had a mean conductance of ∼25 pS. Both individual channel openings (mean open time ∼1 ms) and short bursts of openings (mean burst duration of about a few milliseconds) were observed. In addition, there were smaller events which probably represented other states of the conductance. The mean current increased with the third power of cGMP concentration, suggesting that there are at least three cGMP-binding sites on the channel molecule. With 0.2 mM Mg2+ in the cGMP-containing solution, a flickering block of the open channel was observed; the effect of Ca2+ was similar. The results resolve a puzzle about the light-sensitive conductance by demonstrating that it is an aqueous pore rather than a carrier.
312 citations
TL;DR: Excluding patients with possible panic-phobic syndromes from the analyses removed most significant antiphobic and antidepressant effects of imipramine but left intact imipramsine's significantly superior antianxiety effects.
Abstract: • A double-blind, placebo-controlled comparison at three collaborating university sites included 242 patients diagnosed as having anxiety disorders. A two-week placebo washout period preceded random assignment to eight weeks of imipramine hydrochloride, chlordiazepoxide hydrochloride, or placebo treatment. Antianxiety effects of imipramine were superior to those of the other two agents by the second treatment week; these effects became more clearly significant thereafter and were independent of degree of both baseline depression and anxiety. Excluding patients with possible panic-phobic syndromes from the analyses removed most significant antiphobic and antidepressant effects of imipramine but left intact imipramine's significantly superior antianxiety effects.
268 citations
TL;DR: Measurements of cell body and peripheral and central axon sizes were made for primary sensory neurons outlined by the intracellular injection of HRP and sensory neurons were subdivided into A and C cells on the basis of the conduction velocity of the impulses carried by the processes of these cells.
Abstract: Measurements of cell body and peripheral and central axon sizes were made for primary sensory neurons outlined by the intracellular injection of HRP. Conduction velocities were also measured on the outlined processes. The sensory neurons were then subdivided into A and C cells on the basis of the conduction velocity of the impulses carried by the processes of these cells. Central processes of both A and C cells are smaller than the peripheral processes, but the size differential is greater for the C cells. For A cells there is a linear relation between the size of the peripheral axon and the conduction velocity of the impulses carried by these axons, but the confidence limits are wide. For C cells there is a linear relation between the size of the central process and conduction velocity of the impulses carried by the processes, but for the peripheral processes two aberrant processes resulted in no correlation between process size and conduction velocity. For A cells, the size of the central and peripheral processes and the conduction velocity of the impulses carried by the peripheral processes are linearly correlated with cell body size. By contrast no such correlations can be demonstrated for C cells. This presumably implies an important difference in that the size of the cell body is correlated with axon size and impulse conduction velocity for A cells but not for C cells. A widely accepted generalization is that large sensory cells give rise to myelinated axons and small sensory cells to unmyelinated axons. In this study, myelinated and unmyelinated are defined on the basis of impulse conduction velocity. For those cells that are clearly large (greater than 50 microns in diameter), the conduction velocity of the impulses carried by their processes is always greater than 2.5 m/s, and for those cells that are clearly small (less than 35 microns in diameter), the conduction velocity is always less than 2.5 m/s. Thus for these cells the above generalization holds. For the intermediate-sized cells (35-50 microns), however, the size of the cell body bears no predictable relation to the conduction velocity of the impulses carried by those processes, and thus to whether the axons are myelinated or unmyelinated. Thus the above generalization does not hold for this intermediate group of cells, and since there are many cells in this size range, we feel that the generalization that large cells give rise to myelinated axons and small cells to unmyelinated axons is an oversimplification.
252 citations
TL;DR: Curved or spiral gramnegative bacilli were isolated from 10 of the specimens on chocolate agar incubated at 37 C under microaerophilic conditions and resembled the organism recently named Campylobacter pyloridis by other investigators.
Abstract: Biopsy specimens from the gastric antral mucosa of 50 patients with upper gastrointestinal complaints were studied by light and electron microscopy and culture. Of 46 assessable specimens, seven were histologically normal, and 39 showed evidence of gastritis. Twenty-seven of the specimens with evidence of gastritis (69%) contained spiral bacteria, whereas only one of the normal specimens (14%) contained these bacteria (P = .02). Of 17 patients found to have gastric ulcers, 10 (59% [P greater than .10] ) also had spiral bacteria. The bacteria could be seen scattered over the surface of the epithelial cells and just under the layer of mucus but were rarely found inside the epithelial cells. Curved or spiral gramnegative bacilli were isolated from 10 of the specimens on chocolate agar incubated at 37 C under microaerophilic conditions. The bacteria resembled the organism recently named Campylobacter pyloridis by other investigators.
248 citations
TL;DR: The authors conclude that TPN may be useful when used preoperatively in patients with gastrointestinal tract cancer and underscores the importance of demonstrating significant benefits in randomized trials before TPN is used routinely in these patients.
Abstract: Twenty-eight prospective randomized controlled clinical trials evaluating the use of total parenteral nutrition (TPN) in cancer patients were identified through a search of major indexing sources. The data were pooled across studies to increase the ability to detect therapeutic effects. The impact of publication bias and the quality of reporting each trial were used to critically assess the conclusions drawn from the pooled analysis. The authors conclude that TPN may be useful when used preoperatively in patients with gastrointestinal tract cancer. It appears to be beneficial in reducing major surgical complications (pooled P = 0.01) and operative mortality (pooled P = 0.02). No statistically significant benefit from TPN could be demonstrated in survival, treatment tolerance, treatment toxicity, or tumor response in patients receiving chemotherapy or radiotherapy. An increase in the risk of developing an infection in chemotherapy patients given TPN (pooled P less than 0.0001) underscores the importance of demonstrating significant benefits in randomized trials before TPN is used routinely in these patients.
241 citations
TL;DR: The incidence of and mortality from inhalation injury both rose with increasing burn area and also rose with advancing age; mortality was lowest in the 5- to 14-year old age group and highest in those more than 59 years of age.
Abstract: A retrospective analysis of 1,018 consecutive admissions with cutaneous burn injury over 32 months was carried out. Mortality probabilities as related to age, per cent TBSA burn, and presence of inhalation injury are presented. Incidence of and mortality from inhalation injury both rose with increasing burn area. The incidence of inhalation injury also rose with advancing age; mortality was lowest in the 5- to 14-year old age group and highest in those more than 59 years of age. Language: en
Journal Article•
TL;DR: Comparison of PCP inhibition of NMDA-stimulated ACh and DA release with that produced by the competitive NMDA antagonist 2-amino-5-phosphonovalerate indicates that PCP is probably not altering release by a direct action on the NMDA recognition site.
Abstract: In the present study, the authors found that, in Mg++-free buffer, N-methyl-D-aspartate (NMDA) was able to evoke the Ca++-dependent and tetrodotoxin-sensitive release of striatal acetylcholine (ACh), presumably via interaction with receptors on cholinergic interneurons. In Mg++-free buffer containing pargyline, NMDA also evoked a Ca++-dependent and tetrodotoxin-sensitive release of striatal [3H]dopamine (DA). Phencyclidine (PCP) and physiological concentrations of Mg++ (1.2 mM) also inhibited ACh release evoked by L-glutamate, L-aspartate and DL-homocysteate, but not ACh release evoked by the glutamate analogs quisqualate and kainate, suggesting that PCP is selective for the magnesium-sensitive, NMDA-preferring glutamate-aspartate receptor subtype. Comparison of PCP inhibition of NMDA-stimulated ACh and DA release with that produced by the competitive NMDA antagonist 2-amino-5-phosphonovalerate indicates that PCP is probably not altering release by a direct action on the NMDA recognition site. The ability of 2-amino-5-phosphonovalerate, but not PCP, to prevent desensitization of NMDA-induced ACh release is consistent with this interpretation. Binding studies did, however, reveal a reduction in the apparent affinity of the PCP binding site by high concentrations of NMDA. This may suggest an allosteric link between the PCP-sigma receptor and the NMDA-type glutamate-aspartate receptor. The receptors mediating excitatory amino acid-induced DA release were somewhat less selective than those on cholinergic neurons in their sensitivity to both Mg++ and PCP. Structure-activity-relationship studies suggested that the inhibition off ACh and DA release evoked by NMDA involves biding to the PCP-sigma receptor.(ABSTRACT TRUNCATED AT 250 WORDS)
01 Jan 1986
TL;DR: An improved combination electromagnetic suspension, dampening, lateral stability and axial separation system for a surface supported transportation vehicle having a sprung load carrying portion and an unsprung surface contacting portion with a controllable air gap therebetween.
Abstract: An improved combination electromagnetic suspension, dampening, lateral stability and axial separation system for a surface supported transportation vehicle having a sprung load carrying portion and an unsprung surface contacting portion with a controllable air gap therebetween. The apparatus of the system comprises separate controllable transverse electromagnets having a concave profile cooperating with a convex superposed ferromagnetic member for suspension. Additionally, the ferromagnetic member has separate controllable electromagnets cooperating with the suspension magnets for lateral stability. Additional separately controllable electromagnets and cooperating ferromagnetic members are provided to prevent axial instability between the sprung and unsprung vehicle portions during acceleration and deceleration. The control circuits provide non-linear feedback so as to substantially maintain a preselected gap distance between the various electromagnets and their associated ferromagnetic member.
TL;DR: There was a positive but nonsignificant correlation between SES, both current and projected, and higher EAT scores, and the relationship suggested by various investigators between cultural factors and a higher incidence of eating disorders was supported.
Abstract: The relationship of culture and socioeconomic status (SES) to eating attitudes in a nonclinical group of 138 Hispanic females, ages 16-18 is investigated. The instruments used included the Eating Attitudes Test (EAT), a 40-item self-rated scale that assesses abnormal eating attitudes, a rationally derived 15-item scale measuring degree of acculturation to American culture, and the Hollingshead-Redlich two-point measure of SES. The Hispanic subjects' EAT results were compared to those from a large group of predominantly white, Southern adolescent girls. Although the Hispanic group was similar on their EAT scores to the Southern group, there was a significant correlation between acculturation and higher EAT scores. There was a positive but nonsignificant correlation between SES, both current and projected, and higher EAT scores. The results support the relationship suggested by various investigators between cultural factors and a higher incidence of eating disorders. They fail to support the hypothesized relationship between higher SES and vulnerability to these disorders.
TL;DR: An hypothesis was developed which predicts that human milk protects against infections of the alimentary tract of the breast‐fed infant by non‐inflammatory mechanisms.
Abstract: An hypothesis was developed which predicts that human milk protects against infections of the alimentary tract of the breast-fed infant by non-inflammatory mechanisms. Human milk is poor in the initiators and mediators of inflammation and rich in anti-inflammatory agents. Furthermore, many of the anti-inflammatory agents are comparatively resistant to digestive enzymes and therefore might be expected to remain active in the gastrointestinal tract of the recipient. Further studies of these factors in in vivo models will be required to validate the hypothesis.
Journal Article•
TL;DR: The studies demonstrate that the trophic effects of gastrin on MC-26 cells are probably mediated by its regulation and maintenance of the binding affinity and capacity of Gastrin receptor on the cancer cells, in vivo.
Abstract: We recently reported trophic response of transplantable mouse colon cancer cells (MC-26) to pentagastrin, in vivo, and demonstrated gastrin receptors on MC-26 cells, in vitro. In the present study, growth of MC-26 cells in mice, in response to pentagastrin, was studied in relation to binding kinetics and capacity of gastrin receptor. Gastrin receptor levels on mouse fundic and colonic membranes and on MC-26 cellular membranes were determined before MC-26 cell inoculation and designated as Day 0 levels. Four groups of mice were next inoculated with MC-26 cells and given injections of either pentagastrin (treated) or normal saline (control) for 10 or 15 days. At the end of the treatment periods, body, tumor, fundic, and colon weights were noted and gastrin receptor measured. tumor and fundic weights increased significantly within 15 days of pentagastrin treatment, compared to control values. In control (non-pentagastrin treated) mice, the binding affinity of gastrin receptor on tumor membranes was significantly decreased and associated with the complete loss of high-affinity gastrin receptor (Kd = less than 0.5 nM) by Day 15 of tumor growth. On the other hand, both the binding affinity and gastrin receptor levels of tumor membranes were maintained at Day 0 values by pentagastrin treatment. Endogenous gastrin was therefore ineffective in maintaining high-affinity gastrin receptor on control tumors. A significant number of low-affinity gastrin-binding sites (Kd = less than 2 nM) appeared in control tumors by Day 15, which could reflect rapid dedifferentiation or conformational changes of gastrin receptor in the absence of high levels of normal regulatory hormones. These studies demonstrate that the trophic effects of gastrin on MC-26 cells are probably mediated by its regulation and maintenance of the binding affinity and capacity of gastrin receptor on the cancer cells, in vivo.
TL;DR: The effects of gastrin treatment on the growth of MC-26 colon cancer persist after treatment is discontinued; mice with tumors that were treated with gastrin for either 7 or 14 days and in which the treatment was stopped were all dead by 35 or 28 days, respectively, after the end of treatment.
TL;DR: Intimate spatial associations that would probably not be detected by an examination of adjacent sections stained for each antigen can be visualized with this two-color immunoperoxidase method.
Abstract: A method for differentially staining for two antigens in single sections is described. Paraffin-embedded or Vibratome sections are incubated in two sequences of immunoperoxidase (PAP) reagents using a diaminobenzidine (DAB)-nickel ammonium sulfate solution to localize the first antigen, and DAB alone to localize the second antigen. With these chromagens, black and amber-colored reaction products are generated at the locations of the first and second antigens, respectively. The reaction products are stable and provide excellent color contrast. With this technique, the anatomical relationships between two sets of immunoreactive elements can be studied in individual sections. Intimate spatial associations that would probably not be detected by an examination of adjacent sections stained for each antigen can be visualized with this two-color immunoperoxidase method.
TL;DR: Based on the data generated by this study, it is recommended as hormonal therapy 0.1–0.5 mg/day of ethinyl estradiol or 7.5–10 mg/ day of conjugated estrogen for male-to-female transsexuals, and intramuscular testosterone cypionate, 200 mg every 2 weeks, for female- to-male transsexuals.
Abstract: The physical and hormonal characteristics of 60 male-to-female transsexuals and 30 female-to-male transsexuals were measured before or during treatment with commonly used forms and dosages of hormones. Only two patients (both female-to-male) had either a congenital defect in hormonal production or abnormal genital development. Patients were seen at 3- to 6-month intervals for an average of 18 months. The response to therapy was examined over time; physical parameters, hormonal concentrations, liver function tests, lipids, and glucose were measured. Three patients were changed from ethinyl estradiol to conjugated estrogen because of liver enzyme elevations. Ethinyl estradiol (0.1–0.5 mg/day) was equal to conjugated estrogen (7.5–10 mg/day) in its ability to suppress testosterone and gonadotropins and to promote breast growth. Maximum breast growth required 2 years of therapy. During treatment with testosterone, female-to-male transsexuals had a significant mild elevation of cholesterol and triglyceride. The female-to-male transsexuals receiving testosterone cypionate, 200 mg every 2 weeks, ceased to have menstrual periods and became progressively masculinized. A mean maximal clitoral length of 4.6 cm which achieved by 1 year of therapy. Based on the data generated by this study, we recommend as hormonal therapy 0.1–0.5 mg/day of ethinyl estradiol or 7.5–10 mg/day of conjugated estrogen for male-to-female transsexuals, and intramuscular testosterone cypionate, 200 mg every 2 weeks, for female-to-male transsexuals.
TL;DR: Thirty-two burned children admitted from 1977 through 1981 were treated by serial debridement of their burn wounds with 1:1.5 to 3:1 meshed autografting of granulating tissue as it became available, and thirty-two treated by early total excision to fascia with application of 4:1 expanded autografted and cadaver skin for complete closure.
Abstract: Thirty-two children admitted from 1977 through 1981 were treated by serial debridement of their burn wounds with 1:1.5 to 3:1 meshed autografting of granulating tissue as it became available. Thirty-two burned children treated from 1981 to 1984 were treated by early total excision to fascia with app
TL;DR: The data reemphasize the significance of viruses as etiologic agents of acute otitis media and propose several questions regarding the viral-bacterial interactions and the types of viruses involved in the pathogenesis of the disease.
Abstract: During a 28-month period, 84 children with acute otitis media were studied by viral and bacterial cultures of middle ear fluid and viral cultures of nasal lavage fluid. Viruses were isolated from the middle ear fluid of 17 (20%) patients. Evidence of viral infection was demonstrated by positive viral cultures of middle ear fluid and/or nasal lavage fluid in 33 (39%) patients. Rhinovirus in one patient and influenza b virus in another were the only pathogens isolated. Influenza virus, enterovirus, and rhinovirus were the most common viruses found in middle ear fluids. Parainfluenza virus, adenovirus, and respiratory syncytial virus were found less often. In 82% of cases, the virus isolated from middle ear fluid was also isolated from nasal lavage fluid, but only 44% of viruses found in nasal lavage fluid were also found in middle ear fluid. Mixed bacterial and combined viral-bacterial infections were common. Only 15% of patients had no pathogen isolated from middle ear fluids. Using tissue culture techniques, we demonstrated that enterovirus and rhinovirus are also common middle ear pathogens. Our data reemphasize the significance of viruses as etiologic agents of acute otitis media and propose several questions regarding the viral-bacterial interactions and the types of viruses involved in the pathogenesis of the disease.
TL;DR: The effects of dihydropyridine Ca channel ligands (DHPs), mainly nitrendipine and Bay K8644, on whole cell and single channel Ca currents on single myocytes isolated from the adult guinea‐pig ventricle are studied.
Abstract: We studied the effects of dihydropyridine Ca channel ligands (DHPs), mainly nitrendipine and Bay K8644, on whole cell and single channel Ca currents on single myocytes isolated from the adult guinea-pig ventricle. Nitrendipine had dual effects, stimulatory or inhibitory, depending upon the membrane potential. At low frequencies (less than 0.03 Hz) and negative holding potentials (-90 mV or more), nitrendipine increased the Ca currents in a dose-dependent manner. The dose-response curve was best fitted by a Langmuir adsorption isotherm model which was the sum of two independent one-to-one drug-receptor sites with median effective doses (ED50S) of 1.0 X 10(-9) M and 1.4 X 10(-6) M respectively. When the membrane potential was held at -30 mV or less, nitrendipine inhibited the Ca currents, also in a dose-dependent manner. The dose-response curve was fitted by a single binding site model having a median inhibitor concentration (IC50) of 1.5 X 10(-9) M. At holding potentials between -70 and -40 mV, nitrendipine produced mixed effects on Ca currents; an increase occurred initially and this was followed by a decrease. When rundown was excluded, Bay K8644 showed only stimulatory effects on the Ca currents between holding potentials of -120 and -30 mV. When the test potential was zero or +10 mV the Ca currents reached peak values and the dose-response curve was best fitted by a single binding site model having an ED50 of 3 X 10(-8) M. When the effects were measured at negative test potentials of -30 to -10 mV, the curve was best fitted by a two-site model with ED50S of 3 X 10(-9) and 9 X 10(-7) M. At the single Ca channel level the stimulatory effect of nitrendipine was due to an increased probability that a Ca channel which had opened once would reopen, a reduction in records without activity and an increase in the mean open time. There were no changes in unit conductance. Inhibitory effects were due to a large increase in nulls. At lower concentrations the main effect of Bay K8644 was an increase in the probability of opening. At doses above 10(-6) M, a pronounced increase in the open time was observed. The effects we observed are attributed to at least two sites for DHP related to Ca channels; one with high affinity and one with a lower affinity. The low affinity site mediates a stimulatory effect due to greatly prolonged openings.(ABSTRACT TRUNCATED AT 400 WORDS)
TL;DR: Six additional patients with similar cytogenetic and phenotypic abnormalities resulting from a small interstitial deletion of 17p are identified and Chromosome studies with special attention to 17 should be performed in any patient with a similar phenotype.
Abstract: Recently, a new clinically recognizable syndrome resulting from a small interstitial deletion of 17p [del(17)(p11.2p11.2)] was described in ten unrelated patients. We have identified six additional patients with similar cytogenetic and phenotypic abnormalities. Consistent clinical manifestations include 1) brachycephaly with a broad face and nasal bridge, 2) flat midface, 3) short, broad hands, and 4) mental retardation associated with hyperactivity and often self-destructive behavior. The craniofacial and hand anomalies are reminiscent of several craniosynostosis syndromes. Most patients also had growth deficiency and several other (more variable) congenital malformations. Chromosome studies with special attention to 17 should be performed in any patient with a similar phenotype.
TL;DR: In severely burned patients hyperglucagonemia stimulates increased glucose production, basal insulin suppression glucoseProduction, stimulates basal glucose clearance, and is important for regulation of plasma amino acid concentrations, and the selective lowering of glucagon while maintaining basal insulin constant normalized glucose kinetics.
Abstract: We investigated the roles of insulin and glucagon as mediators of changes in glucose and alanine kinetics during the hypermetabolic response to injury in 10 burn patients by infusing somatostatin with and without insulin replacement. Glucose and alanine kinetics were measured by primed-constant infusions of 6,6-d2-glucose and [3-13C]alanine. The basal rate of glucose production and alanine flux were significantly elevated in all patients. Lowering both hormones simultaneously caused an insignificant reduction in glucose production, but plasma glucose rose significantly (P less than 0.01), because of reduced clearance. Alanine flux and total plasma amino nitrogen increased significantly (P less than 0.05) above basal. Selectively lowering glucagon concentration decreased glucose production (P less than 0.05), and exogenous glucose was infused to maintain euglycemia. Alanine flux and total plasma amino nitrogen remained unchanged. In severely burned patients hyperglucagonemia stimulates increased glucose production, basal insulin suppression glucose production, stimulates basal glucose clearance, and is important for regulation of plasma amino acid concentrations, and the selective lowering of glucagon while maintaining basal insulin constant normalized glucose kinetics.
TL;DR: The results provide evidence for some preserved semantic memory following closed-head injury and their implications for rehabilitation are discussed.
Abstract: Verbal learning and memory over repeated trials were studied in 12 severely closed-head-injured patients and a matched control group of 10 subjects for three types of word lists, i.e., unrelated, related but unclustered, and clustered words. Verbal memory was facilitated in both groups by presentation of related words in a clustered format. However, the performance of head-injured patients was characterized by low levels of recall, clustering, and subjective organization. In addition, they had a larger number of intrusive errors. The results provide evidence for some preserved semantic memory following closed-head injury and their implications for rehabilitation are discussed.
TL;DR: The activity of 132 neurons in the caudal part of the ventral posterior lateral nucleus (VPLc) of the thalamus was recorded from 23 anesthetized monkeys and suggested that a large population of VPLc neurons respond to mechanical nociceptive stimuli either exclusively or preferentially.
Abstract: The activity of 132 neurons in the caudal part of the ventral posterior lateral nucleus (VPLc) of the thalamus was recorded from 23 anesthetized monkeys. All single thalamic units that could be exc...
TL;DR: Self-rated decline in memory relative to estimated abilities at age 60 was investigated in a group of normal elderly subjects and self-ratings of storage, retrieval, attention/concentration, remote memory, and depression formed a factor which was orthogonal to objective measures of memory function.
Abstract: Self-rated decline in memory relative to estimated abilities at age 60 was investigated in a group of 88 normal elderly subjects age 60 to 90. Self-ratings of storage, retrieval, attention/concentration, remote memory, and depression formed a factor which was orthogonal to objective measures of memory function. Self-rated remote memory was also associated with objective measures of recent/remote memory, and self-rated depression was additionally related to objective measures of attention/concentration.
TL;DR: It is concluded that a classification scheme based on a cluster analysis of the responses of neurons to standardized stimuli may provide an objective and functionally meaningful way to categorize somatosensory neurons.
Abstract: Data analyzed in this study were derived from the responses of 128 spinothalamic tract (STT) cells and 110 thalamic neurons recorded in 75 anesthetized monkeys. A k-means cluster analysis, a nonhierarchical clustering technique, was performed using the relative magnitudes of responses to a graded series of innocuous and noxious mechanical stimuli applied to the receptive field. For comparison, a parallel analysis was performed based on definitions of low-threshold (LT), wide dynamic range (WDR), and high-threshold (HT) cells used by our laboratory. For 128 STT cells, a classification scheme with three clusters was found statistically to be the best. This yielded groups of 22, 57, and 49 cells in clusters 1, 2, and 3, respectively. Cluster 1 cells were activated best by low-intensity mechanical stimuli, whereas cluster 3 cells were activated primarily by nociceptive stimuli. Cluster 2 cells had intermediate characteristics. When the classification scheme based on the cluster analysis was compared with the classification of the same neurons as LT, WDR, and HT cells, cluster 1 cells were divided into LT and WDR cells, whereas cluster 2 and 3 cells included WDR and HT cells. For 110 thalamic neurons, a classification scheme with five clusters was found statistically to be the best. Clusters 1-5 contained 25, 34, 17, 10, and 24 cells, respectively. Response characteristics of cells in each group indicated a gradual change in sensitivity to higher intensities of peripheral input from cluster 1 to 5. When this classification scheme was compared with the classification scheme previously used by our laboratory, cluster 1 cells belonged to the LT group, clusters 2 and 3 split into LT and WDR cells, and clusters 4 and 5 included WDR and HT cells. It is concluded that a classification scheme based on a cluster analysis of the responses of neurons to standardized stimuli may provide an objective and functionally meaningful way to categorize somatosensory neurons.
TL;DR: Significant correlations among basal levels of plasma insulin, and both testosterone and androstenedione were demonstrated in evaluating the relationship between hyperandrogenemia, insulin resistance, and acanthosis nigricans.
Abstract: The roles of hyperandrogenemia and obesity in the syndrome of severe insulin resistance with acanthosis nigricans were evaluated in studies of 11 females with this condition. Our results in these subjects were compared to evaluations of control subjects matched for degree of androgen excess or obesity. Fasting insulin levels were 3-, 5-, and 15-fold higher in the obese (OB), hyperandrogenemic (HO), and acanthosis nigricans (AN) groups, respectively, when compared to normal females. Responsiveness to a standard bolus of exogenous insulin was 78% of normal in the OB group, 40% of normal in the HO group, and 30% of normal in the AN group. Insulin binding to monocytes from both the OB group, and the HO group was modestly diminished primarily due to decreased receptor number. As a group, AN subjects when compared to either normal or weight-matched controls, demonstrated a significant decease in monocyte insulin binding predominantly due to a decrease in receptor number. However, two patients in the AN group had normal insulin binding suggesting a postreceptor mechanism for the insulin resistance in at least some of these subjects. In vivo glucose utilization insulin dose response curves were determined in 3 acanthotic subjects using the euglycemic clamp technique. All 3 of these subjects had a right shift of the curve and diminished maximal utilization, consistent with combined receptor and postreceptor defects in insulin action. In evaluating the relationship between hypeandrogenemia, insulin resistance, and acanthosis nigricans, significant correlations among basal levels of plasma insulin, and both testosterone and androstenedione were demonstrated. Further, the severity of the acanthosis nigricans was directly related to the degree of hyperinsulinemia and was not correlated to the level of androgens. Our data suggest that the insulin resistance seen in obese acanthotic subjects cannot be attributed to hyperandrogenemia or obesity, since control subjects matched for severity of androgen excess or degree of obesity had much less insulin resistance.
TL;DR: It is suggested that a significant degree of insulin resistance exists in women with hyper thecosis and that insulin stimulates ovarian stromal androgen synthesis and thus may play a role in the pathogenesis of ovarian hyperthecosis.