Antenatal testing for haemoglobinopathies.
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Female↗
Biomedical subjects
R J Amos
Publications and source records attributed to R J Amos.
Questionable dieting behaviors are used by young adults regardless of sex or student status.
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Adolescent↗
Nutrition information needs during cardiac rehabilitation: perceptions of the cardiac patient and spouse.
A survey instrument, which was developed from personal interviews with participants in a cardiac rehabilitation program, was administered at two hospital-based Phase II cardiac rehabilitation programs. Thirty-five patients (28 men, 7 women) and 29 spouses (5 men, 24 women) responded to survey items designed to investigate how subjects perceived themselves dealing with the cardiac diet, what questions they were asking, and how answers to those questions would help them. Subjects in the patient group (which was 80% male) most frequently asked questions dealing with compliance and the diet's benefits. Subjects in the spouse group (which was 83% female) most frequently asked questions relating to food selection. Participants indicated that having their questions answered would help them make decisions, be motivated, feel in control, and plan. Participants' overall attitude toward the diet was positive because patients were willing to make changes in their diet; however, more than half the sample thought food labels were difficult to understand and grocery shopping was difficult. We conclude that nutrition education programs that address individual needs and uses for nutrition information could enhance the learning process in group settings such as cardiac rehabilitation programs.
Adult↗
Observations on the haemopoietic response to critical illness.
Peripheral blood cytopenias are common in patients receiving intensive care, particularly in those with multiple organ failure. To assess the contribution of bone marrow hypoplasia in such patients 44 bone marrow samples from 24 patients under intensive care were studied by standard morphological techniques and by the granulocyte-macrophage colony forming cell (GM-CFC) assay. Frequently observed morphological abnormalities in the bone marrow included the following: (i) a reduction in overall cellularity in seven patients, with a progressive decrease in most patients studied sequentially; (ii) an increase in the number of actively phagocytic macrophages; and (iii) a disruption of normal bone marrow architecture with the accumulation of intercellular hyaluronic acid glycosaminoglycan. Mean GM-CFC growth was significantly reduced when compared with that in a group of normal controls. In four of five patients studied sequentially GM-CFC growth became subnormal in association with a reduction in bone marrow cellularity. Inhibitory serum factors were not identified. These morphological abnormalities are similar to the changes observed in gelatinous degeneration of the bone marrow. In both situations disruption of the haemopoietic microenvironment, with the accumulation of hyaluronic acid proteoglycan, may be an important factor in the inhibition of haemopoietic progenitor cell growth. The proliferation of macrophages, by the release of a variety of cytokines or reactive oxygen intermediates, may also be implicated in impaired haemopoiesis and the development of disordered erythropoiesis.
Adolescent↗
Intravenous immunoglobulin therapy in thrombocytopenic infectious mononucleosis.
Severe haemorrhagic thrombocytopenia in infectious mononucleosis with positive Epstein-Barr virus (EBV) serology remains a threatening clinical problem. Although rare, fatalities have been reported. We present clinical, haematological and serological details of two patients with diffuse bleeding associated with this disease who failed conventional steroid treatment and who both responded promptly and effectively to infusions of intravenous immunoglobulin (i.v. Ig). A platelet immunofluorescence test was used to detect platelet antibodies in acute and recovery phase patient sera against autologous recovery platelets and against normal allogeneic group O platelets. In one patient, indirect immunofluorescence using recovery platelets detected an IgG platelet autoantibody with acute phase autologous serum. No platelet antibody was detected in the second patient. The data presented demonstrate that response to i.v. Ig is independent of serological detection of platelet autoantibodies. Therapy with i.v. Ig should be considered in any case of haemorrhagic thrombocytopenia associated with EBV infection shown to be refractory to steroid treatment.
Adult↗
Developing a strategy for understanding adolescent nutrition concerns.
Disseminating nutrition information that adolescents will incorporate into their lives has been a difficult challenge for nutrition educators. The communication of such information has often been a "one-way street"; adolescents are given information that educators feel they need to have. Researchers contend that a more effective way to communicate is for adolescents to describe what they need to know in order to relate nutrition messages to their own worlds. A research model based on Brenda Dervin's work with the "sense-making" theory of communication was used to better determine adolescents' perceived nutrition concerns. Adolescents aged 14 to 16 across six states were interviewed to record personal situations they experienced concerning food, nutrition, and/or eating. Situation "movement states" were identified to determine the qualitative ways in which the adolescents perceived themselves as dealing with the situations they described. Data indicate that this theoretical base may be used by nutrition educators to identify adolescents' nutrition needs and to design appropriate education materials.
Adolescent↗
The sense-making approach for audience assessment of adolescents.
The purpose of the research was to test the methodology used to identify how adolescents approach their nutrition concerns and questions. The methodology was based on Dervin's sense-making theory. Using a time-line interview technique, 305 adolescents 14 to 16 years of age detailed a situation involving their most important nutrition concerns. Other pertinent information was obtained. Cluster analysis was chosen as the appropriate analysis to identify groups of adolescents who responded similarly to the technique. Discriminant analysis was then used to determine which variables maximally separated the groups. Four groups were identified, two of which described action-oriented approaches to dealing with nutrition situations and differed in terms of how much outside help they wanted. The remaining two groups perceived barriers to dealing with situations and also differed in how much help they wanted. A fifth group indicated no nutrition concerns or questions. The results will be used to develop and test the effectiveness of nutrition education when it is focused on the different approaches.
Adolescent↗
Autosomal inheritance of sideroblastic anaemia.
Inherited sideroblastic anaemia is usually transmitted as an X-linked disorder (Losowsky & Hall 1965). We report a patient in whom family studies indicated autosomal inheritance, with direct transmission from father to son. The severe nature of the sideroblastic abnormality in the proband may be due to interaction between the sideroblastic trait and a single allele for idiopathic haemochromatosis.
Adult↗
Bone marrow hypoplasia during intensive care: bone marrow culture studies implicating ranitidine in the suppression of haemopoiesis.
Two seriously ill patients with renal failure developed bone marrow hypoplasia and peripheral blood cytopenias during admission to an Intensive Care Unit (ICU). Both patients were being treated with ranitidine and, in both, there was evidence of drug accumulation. Serum from the patient with the highest concentration of ranitidine inhibited granulocyte-macrophage colony growth from normal bone marrow. The addition of ranitidine to cultures of normal bone marrow also produced a concentration-dependent inhibition of colony growth. Ranitidine should be used with caution in patients with renal failure where drug accumulation may seriously impair bone marrow function.
Aged↗
Adolescents' beliefs about and reasons for using vitamin/mineral supplements.
Beliefs about and reasons for using vitamin/mineral supplements were investigated among 163 adolescents. Subjects' responses to belief statements about supplements and reasons cited for using supplements demonstrated both misconceptions and uncertainties. These results demonstrate the need for dietitians to routinely address the appropriate use of nutritional supplements with their adolescent clientele.
Adolescent↗
Toxicity of bone marrow in dentists exposed to nitrous oxide.
The morphology of the bone marrow of 21 dentists who habitually used nitrous oxide in their surgeries was investigated. Exposure to nitrous oxide was measured with an atmospheric sampling device, and each dentist was invited to fill in a questionnaire giving details of medical history, diet, and intake of alcohol. During the trial a full neurological and haematological investigation was carried out and a bone marrow aspirate was examined both morphologically and by the deoxyuridine suppression test. Mean exposures to nitrous oxide ranged from 159 to 4600 parts per million. In all subjects serum vitamin B12 and folate concentrations were within normal limits. Abnormal results of deoxyuridine suppression tests were obtained in three of the 20 dentists tested; two of these three had abnormal white cells in their peripheral blood films. This study provides direct evidence that occupational exposure to nitrous oxide may cause depression of vitamin B12 activity resulting in measurable changes in bone marrow secondary to impaired synthesis of deoxyribonucleic acid.
Anesthesia, Dental↗
Role of S-adenosylmethionine in DNA synthesis and haemopoiesis.
In man, exposure to nitrous oxide (N2O) can produce neurological damage and megaloblastic change in the bone marrow due to inactivation of vitamin B12. Methionine metabolism is interrelated with that of vitamin B12 and folate; the effect of methionine on the impaired DNA synthesis produced by N2O was therefore studied in 17 patients undergoing surgery. 14 were anaesthetised with 50% N2O in oxygen for 3-24 h. The remaining 3 had been exposed to N2O for less than 3 h. All patients developed megaloblastic bone marrow change except 2 of the latter patients whose bone marrows remained normoblastic. The bone marrow was studied biochemically using the deoxyuridine (dU) suppression test. The in vitro addition of small doses of methionine was as effective as vitamin B12 itself in correcting the defective DNA synthesis produced by N2O. It is suggested that N2O impairs methionine biosynthesis, methionine, in the form of S-adenosylmethionine (SAM), being required for DNA synthesis and the prevention of the development of megaloblastic anaemia in man.
Bone Marrow↗
Investigations into the effect of nitrous oxide anaesthesia on folate metabolism in patients receiving intensive care.
Anaesthesia with nitrous oxide inactivates vitamin B12 and impairs DNA synthesis in bone marrow cells. The secondary development of folate deficiency may prolong the recovery from these abnormalities in some seriously ill patients. This was investigated, using the deoxyuridine (dU) suppression test, in 48 patients admitted to an Intensive Care Unit (ICU). On admission to the ICU, following nitrous oxide anaesthesia, the pattern of correction of the abnormal dU-suppression tests was typical of that seen in vitamin B12 deficiency; 3 days later the pattern had changed to that usually seen in folate deficiency. During the same period the serum folate levels fell to subnormal values. Further evidence for the development of folate deficiency was provided by treatment with physiological amounts of folic acid which accelerated the recovery of the bone marrow abnormalities present after nitrous oxide anaesthesia. Urinary folate excretion was measured by radioassay, and increased following anaesthesia with nitrous oxide, however, this was insufficient by itself to explain the development of folate deficiency.
Adolescent↗
Prevention of nitrous oxide-induced megaloblastic changes in bone marrow using folinic acid.
Prolonged anaesthesia with nitrous oxide inactivates vitamin B12 and impairs DNA synthesis in bone marrow cells. The use of parenteral folinic acid in the prevention of these toxic effects has been studied in 11 patients, ventilated artificially with nitrous oxide in oxygen for 24 h. Bone marrow aspirates were performed before and after exposure to nitrous oxide. They were assessed morphologically and with the deoxyuridine suppression test. Folinic acid 30 mg immediately before anaesthesia and 30 mg 12 h later, prevented the toxic effects of nitrous oxide in four out of five patients, whereas smaller amounts of folinic acid (between 3 and 36 mg in 24 h), were ineffective.
Adolescent↗
Megaloblastic haemopoiesis due to acyclovir.
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Acute Disease↗
The effect of histamine H2 receptor antagonists on platelet aggregation in man.
The in vivo and in vitro effects on the aggregatory response of human platelets to ADP and collagen of a series of imidazole and non-imidazole histamine H2 receptor antagonists, and imidazole derivatives, have been studied. Bolus i.v. administration of the antagonists cimetidine and oxmetidine was without effect. However, inhibition of platelet aggregation was observed in vitro with oxmetidine, metiamide and to a lesser extent burimamide, but not with cimetidine or the non-imidazole antagonist ranitidine. Of the imidazole derivatives only imidazole and its 1-methyl analogue significantly affected platelet aggregation. The relationship between potency as a histamine H2 receptor antagonist, the presence of an imidazole ring structure and the antiaggregatory effectiveness of these compounds is discussed. Although certain antagonists clearly inhibit platelet aggregation in vitro, effects are only seen at drug concentrations exceeding those achieved under normal therapeutic conditions; thus the clinical significance of these observations remains to be determined.
Burimamide↗
Hospital diabetes education: classroom and self-instruction.
This study was conducted to assess the effectiveness of two approaches to instructing hospitalized patients with diabetes mellitus on the food exchange system. Both groups were given the same pretest and post-test, but one group received self-instruction and the other group received classroom instruction. The pretest scores of the two groups indicated differences in their initial understanding of the food exchange system. The mean score on the pretest for the classroom instruction group was 1.95 points higher than for the self-instruction group on the 18-point test. The self-instruction group gained 3.45 more points than the classroom instruction group on their post-test scores. An analysis of gain between pretest and post-test for both groups indicated that both treatments could be considered effective. However, when the pretest was analyzed as an independent variable, it was shown to have an influence on the post-test results. In controlling for the pretest in the analysis of covariance, the LAP treatment was found to be more effective than the classroom instruction for teaching patients with diabetes mellitus about the food exchange system. As diabetes affects persons from all demographic groups, a variety of programs are needed to meet individual needs (15). Demands for education programs in institutions are being met as patients' needs change. The two instructional approaches assessed in this research are recommended as viable options to use in educating the increasing number of persons with diabetes mellitus.
Adolescent↗
Incidence and pathogenesis of acute megaloblastic bone-marrow change in patients receiving intensive care.
The incidence and pathogenesis of acute megaloblastic bone-marrow change and of abnormalities in DNA synthesis, as assessed with the deoxyuridine(dU) suppression test, have been investigated in a prospective study of 70 seriously ill patients admitted to an intensive-care unit. On admission megaloblastic bone-marrow change was present in 22 patients, 18 of whom had been anaesthetised with nitrous oxide for 2-6 h during surgical procedures before admission. 16 of these 18 patients died, compared with 7 of 22 patients in whom haemopoiesis remained normoblastic despite receiving equivalent amounts of nitrous oxide. An abnormal dU-suppression test developed only in patients who had received nitrous oxide; on admission an abnormal dU-suppression test was found in 39 of the 42 patients tested who had been exposed to the anaesthetic. The abnormality produced in the dU-suppression test by nitrous oxide in patients admitted to the intensive-care unit was more severe and recovery was slower than the abnormality seen in patients undergoing cardiac-bypass surgery. During the recovery period from the effects of nitrous oxide the pattern of correction of the dU-suppression test changed from that of vitamin-B12 deficiency to folate deficiency.
Adolescent↗