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Biomedical subjects

J Morris

Publications and source records attributed to J Morris.

At least 541 records · Page 30Linked to original sources
PubMedDate not supplied

Glutamate and cysteinylglycine effects on NMDA receptors: inhibition by ethanol.

Glutamate, the endogenous neurotransmitter at the NMDA receptor, and cysteinylglycine are formed as byproducts of glutathione (GSH) metabolism by gamma-glutamyltranspeptidase. Glutamate and cysteinylglycine were investigated in Fura-2-loaded whole-brain neonatal (< 24 h) dissociated neurons to determine 1) if cysteinylglycine might act as a glycine site coagonist, 2) the inhibitory effects of ethanol on glutamate-stimulated increases in cytosolic calcium concentration (Glu-[Ca2+]i), and 3) the effects of cysteinylglycine on ethanol's inhibition of Glu-[Ca2+]i. Glu-[Ca2+]i (EC50 = 0.7 microM) in these cells was highly specific for NMDA receptor-operated calcium channels as they were dependent on extracellular calcium, enhanced by glycine, and blocked by magnesium, APV, and ethanol. However, because cysteinylglycine did not potentiate Glu-[Ca2+]i nor reverse ethanol inhibition of Glu-[Ca2+]i, it does not appear to act as a glycine coagonist or change the inhibitory sensitivity of ethanol to Glu-[Ca2+]i.

Animals↗
PubMedDate not supplied

Prevalence of hydrocele as a rapid diagnostic index for lymphatic filariasis.

The real burden of lymphatic filariasis in most endemic areas remains unknown even thought it is a major public health problem in many tropical countries, particularly in sub-saharan African. The nocturnal periodicity of the parasite requires parasitological examinations to be done at night. The aim of this study was to develop and validate rapid epidemiological assessment tools for the community diagnosis of lymphatic filariasis, that may be used in the future to determine the distribution of the disease and identify high risk communities in Ghana. Twenty communities with varying endemicity of filariasis were sampled from 3 endemic districts. Community members were selected for the study using a modified Expanded Programme for Immunization (EPI) cluster sampling technique. The prevalence of hydrocele was high (range 4.5-40.75%, mean = 17.78%) and the community prevalence of microfilaraemia correlated well with that of hydrocele (r = 0.84). The findings suggest that it is possible to obtain reliable and valid estimates of the community burden of lymphatic filariasis using the prevalence of hydrocele as a diagnostic index.

Adolescent↗
PubMedDate not supplied

Central nervous system relapse following bone marrow transplantation in stage IV neuroblastoma.

Neuroblastoma is the most common extracranial solid tumor in pediatrics. The disease-free survival rate for patients with stage IV neuroblastoma has improved over the past 10 years secondary to more aggressive induction chemotherapy regimens combined with autologous bone marrow transplantation. The usual sites of recurrence include the site of primary tumor, residual gross disease, bone, and bone narrow. The central nervous system, a rare site of relapse, is being involved with increasing frequency. The authors report two cases of patients with treated stage IV neuroblastoma who had relapses isolated to the CNS.

Bone Marrow Transplantation↗
PubMedDate not supplied

Effects of garlic extract on platelet aggregation: a randomized placebo-controlled double-blind study.

1. Studies of the effects of garlic on platelet aggregation have produced inconsistent results possibly related to variations in study design and in the garlic preparations used. 2. The present study examined the effects on platelet aggregation and serum thromboxane and lyso-platelet activating factor, of feeding garlic extract to healthy men using a placebo-controlled, double-blind design. The effects of the same garlic preparation on platelet aggregation in vitro were also investigated. 3. There were no significant differences in platelet aggregation with adenosine diphosphate, platelet activating factor (PAF) or collagen according to treatment group. Serum thromboxane and lysoPAF also showed no change related to garlic supplements. 4. In vitro aggregation with collagen decreased linearly with increasing amounts of garlic extract, but concentrations were higher than those attainable in vivo. Gastrointestinal side effects prevented the use of higher doses of garlic which must be considered to be pharmacological as they exceed changes achievable by dietary modification.

Adenosine Diphosphate↗
PubMedDate not supplied

MR imaging classification of perianal fistulas and its implications for patient management.

Until recently, imaging had a limited role in the preoperative assessment of perianal fistulas. Magnetic resonance (MR) imaging has been shown to demonstrate accurately the anatomy of the perianal region. In addition to showing the anal sphincter mechanism, MR imaging clearly shows the relationship of fistulas to the pelvic diaphragm (levator plate) and the ischiorectal fossae. This relationship has important implications for surgical management and outcome and has been classified into five MR imaging-based grades. If the ischioanal and ischiorectal fossae are unaffected, disease is likely confined to the sphincter complex (simple intersphincteric fistulization, grade 1 or 2), and outcome following simple surgical management is favorable. Involvement of the ischioanal or ischiorectal fossa by a fistulous track or abscess indicates complex disease related to trans-sphincteric or suprasphincteric disease (grade 3 or 4). Correspondingly more complex surgery may be required that may threaten continence or may require colostomy to allow healing. If the track traverses the levator plate, a translevator fistula (grade 5) is present, and a source of pelvic sepsis should be sought.

Anal Canal↗
PubMedDate not supplied

Using life expectancy to communicate benefits of health care programs in contingent valuation studies.

BACKGROUND: There is growing interest in the use of contingent valuation (CV) to estimate the monetary value of health program benefits. Ideally, CV could be used to value a specific shift in survival curve. However, a shift in survival curve may prove too complex for widespread use in CV instruments. To facilitate the use of CV in valuing longevity benefits, researchers need alternative summary measures that describe the longevity benefit in a single number that is more readily communicated in a CV context. METHODS: The authors compare 2 methods for communicating longevity benefits in a CV survey. Random subsamples of respondents valued a longevity benefit expressed either as a continuing reduction in annual mortality risk or as a gain in life expectancy. To compare the validity of the alternative descriptions, the authors evaluate willingness to pay (WTP) estimates for consistency with theoretical predictions. RESULTS: It is found that WTP for a longevity benefit is sensitive to the framing of the benefit, with respondents expressing higher WTP for the benefit expressed as a life expectancy gain. The life expectancy format performs better than the risk reduction format in one important regard-sensitivity to scope of the benefit-and no worse than the risk reduction format in other regards. CONCLUSION: Expressing longevity benefits in terms of life expectancy appears to hold promise as a method for enhancing the validity of economic evaluation of health care programs.

Adult↗
PubMedDate not supplied

The effectiveness of coma arousal intervention.

Thirty-one patients who were in coma or persistent vegetative state two weeks after sustaining a severe head injury were entered into a coma arousal programme. The coma arousal protocol called for a sequence of vigorous multisensory stimulations to be applied to the patient by a relative for up to eight hours a day for seven days a week. An independent study team monitored two patient outcomes, the time taken to obey a simple command on two consecutive occasions 24 hours apart and patients' score on the Glasgow Outcome Scale 10-12 months post-injury. Outcomes were compared with an historical reference group chosen from the literature, consisting of 135 similarly classified patients. Differences between the pilot study and the reference group patients on initial characteristics suggested that the pilot study patients might have the more favourable outcomes, independent of treatment effect. The sample size was sufficient to detect a 40% improvement in recovery rate. No significant improvements were noted in either the time to obey a simple command (p greater than 0.2) or in the Glasgow Outcome Scale (p greater than 0.25), although the observed difference in the latter group was 11% in favour of the pilot study patients. This study was unable to find any evidence that coma arousal, for all its arduous patient contact, had a markedly better outcome compared with conventional treatment.

Adolescent↗
PubMedDate not supplied

Laser welding of synthetic epikeratoplasty lenticules to the cornea.

We used a milliwatt continuous wave CO2 laser mounted on an operating microscope to study the feasibility of welding synthetic collagen epikeratoplasty lenticules to the cornea. In vitro studies and experimentation in rabbits and monkeys showed no welding effects using direct laser radiation with powers ranging from 17 mW to 1 W. Only tissue shrinkage was observed. Experiments using various adjunctive solders produced a temporary welding effect using 30% bovine serum albumin welded with a power of 35-45 mW, 325 microns spot size, moving the beam 5 mm/sec. The lenticules remained in place until the 4th postoperative day when epithelium grew underneath the lenticule, dislodging it. Histopathologic examination demonstrated epithelial migration over the solder displacing the epikeratoplasty lenticule and anterior stromal denaturization and disruption.

Animals↗
PubMedDate not supplied

Receptor antagonism of leukotriene B4 myotropic activity by the 2,6 disubstituted pyridine analog U-75302: characterization on lung parenchyma strips.

Leukotriene B4 constricts guinea pig lung parenchyma strips in a concentration-dependent manner. The LTB4 structural analog U-75302, 6-(6-[3-hydroxy-1E,5 Z-undecadienyl]-2-pyridinyl)-1,5-hexanediol, was a partial agonist in this system with a potency 300-1000 times less than LTB4. U-75302 constricted lung parenchyma strips only at concentrations greater than 0.3 microM. At concentrations lacking agonist activity U-75302 was an effective antagonist, displacing the LTB4 dose-response curve. Half-maximal responses required 0.10 microM LTB4 in the presence of 0.3 microM U-75302 and 0.01-0.02 microM LTB4 in its absence. The maximal force of contraction was unaffected at this concentration. Concurrent with antagonism of the myotropic response, U-75302 inhibited the LTB4-dependent release of thromboxane B2 from lung parenchyma. This effect was attributable to receptor antagonism, not enzymatic inhibition of phospholipase, cyclooxygenase, or thromboxane synthase. For instance, 0.3 microM U-75302 did not inhibit thromboxane B2 formation by lung parenchyma stimulated with calcium ionophore A23187 and it did not inhibit thromboxane B2 formation by human platelets stimulated with arachidonic acid. U-75302 selectively antagonized the activity of LTB4 and not other myotropic agonists including the thromboxane A2 mimetic U-46619, LTC4, LTD4, AGEPC, PGF2 alpha, and histamine. Receptor antagonists of leukotriene B4 may have multiple beneficial effects on asthmatic or respiratory disorders. These include (i) direct antagonism of LTB4 myotropic actions; (ii) antagonism of LTB4-dependent mediator release; and (iii) antagonism of LTB4 chemotactic action associated with leukocyte infiltration during anaphylactic late phase reactions.

Animals↗
PubMedDate not supplied

Personal health practices of urban adults in Alabama: Davis Avenue Community Study.

The need to establish baseline data on and monitor the personal health practices and beliefs of adults in a community served by health care facilities is well documented. The purpose of the survey was to determine health care practices, personal health behaviors, and health services use of the adults living in the Davis Avenue Community (DAC), a six-census tract area located in Mobile, AL. The DAC's population is approximately 95 percent black. Using methods developed by the National Center for Health Statistics, 402 adults between the ages of 20 and 69 years were interviewed by telephone by trained personnel to ascertain the health-related characteristics of residents in this health services area. Information collected in this survey provided the staff of the Franklin Memorial Primary Health Center, who provide primary health care in the area, with an empirical base on which to plan and market health promotion and education programs for the health services area.

Adult↗
PubMedDate not supplied

Monitoring post-operative effects in day-surgery patients.

This study was undertaken in the day surgical unit to ascertain the morbidity following herniorrhaphy in adult patients. The results showed a reduction in recovery time of 50 minutes when bupivacaine hydrochloride was used. Interestingly, patients given diclofenac sodium and bupivacaine hydrochloride showed no difference in the pain experienced post-operatively from those given only bupivacaine hydrochloride.

Adult↗
PubMedDate not supplied

Universities as resources to state health agencies.

In a survey of the 50 State health agencies in the spring of 1992, officials were asked about their manpower and research needs in the specific areas of administration, behavioral and social science, education and information, environmental health, environmental protection, epidemiology, laboratory, law, occupational health, policy and planning, and statistics. In all, 40 agencies (80 percent) responded. Indepth telephone interviews to determine whether universities and schools and graduate programs in public health filled these needs completed the data collection process. Agency officials indicated that their resources were least adequate in environmental protection, behavioral and social science, and occupational health. They did not feel their research needs were being met. There was a general feeling that universities and schools and programs in public health have different agendas than State agencies and that practical solutions to the shortage of research resources are not forthcoming from these sources. Suggestions are made as to what can be done to improve relationships between those who train public health personnel and those who employ them.

Data Collection↗
PubMedDate not supplied

Demonstration sites for nurse prescribing.

Eight demonstration sites have been selected to show the value of nurse prescribing. This article explains the criteria used to select the sites and suggests ways in which community nurses can best prepare for the responsibilities of prescribing.

Community Health Nursing↗