Ethnic differences in intake and excretion of sodium, potassium, calcium and magnesium in South Africans.

OBJECTIVES: To determine any differences in the urinary excretion and dietary intake of sodium, potassium, magnesium and calcium intake in three South African ethnic groups, and to assess whether the blood pressure-cation association varies according to ethnic status. DESIGN: A cross-sectional study of 325 black, white and mixed-ancestry men and women, conveniently sampled in Cape Town. Twenty-four-hour urine samples were collected on three separate occasions for assessment of urinary electrolytes, and three 24-h dietary recalls for the corresponding urine collection times were administered by two trained fieldworkers. Para-amino benzoic acid was used as a marker of the completeness of urine collection. RESULTS: Mean urinary sodium values equate to a daily salt (sodium chloride) intake of 7.8, 8.5 and 9.5 g in black, mixed-ancestry and white individuals, respectively. In normotensive individuals, black and mixed-ancestry subjects had significantly lower median urinary sodium concentrations than white subjects, but these differences were not evident between black and white hypertensive subjects. No ethnic differences were found for urinary potassium, except for mixed-ancestry normotensive individuals having a lower excretion than white normotensive individuals. Urinary magnesium excretion did not differ across ethnic groups. In both normotensive and hypertensive individuals, urinary calcium concentrations differed between all three groups, with black subjects having the lowest values, approximately less than half those of white subjects. CONCLUSION: White normotensive subjects in Cape Town have higher habitual intakes of sodium, but also higher calcium intakes than their black and mixed-ancestry counterparts. Dietary differences may contribute to ethnic-related differences in blood pressure.     

A New Method for the Simultaneous Quantitation of Platelet-bound Immunoglobuin (IgG) and Complement (C3) Employing an Enzyme-linked Immunosorbent Assay (ELISA) Procedure

An ELISA technique for the quantitation of platelet-bound IgG and C₃ is described. This is an antiglobulin consumption assay using commercial horseradish peroxidase conjugated anti-IgG and anti-C₃ antisera. The greater the amount of antiglobulin consumed by the reaction with platelets the less is available to bind to an immune adsorbent in the form of human serum-coated polystyrene balls. This test can be calibrated by adding known quantities of IgG or C₃ to the specific enzymelinked antibody and the unbound fraction of antiserum is quantitated by allowing it to react with a chromogenic substrate for the enzyme and measuring the intensity spectrophotometrically, thus establishing an inverse relationship with the amount of antigen. Platelets from normal donors and those with non-immunological throm-bocytopenia gave values of 1·3–15·5 ng IgG/10⁶ platelets and 0·22–0·96 ng C₃/10⁶ platelets which are in accordance with the normal ratio of these proteins in normal serum. Fifteen patients in whom immune destruction of platelets was suspected had excess platelet-bound IgG ranging from 30 to 450 ng IgG/10⁶ platelets. In none of these patients could excess platelet-bound C₃ be demonstrated. Compared to the antiglobulin consumption test we have found this test to be superior both technically and in terms of sensitivity and reproducibility.     

Levels and correlates of internalized homophobia among men who have sex with men in Pretoria, South Africa

This study examines levels and correlates of internalized homophobia among men who have sex with men (MSM) in Pretoria, South Africa. Using respondent-driven sampling, we recruited 324 MSM from February to August 2009. Results were adjusted using RDSAT analysis to yield population-based estimates. High levels of internalized homophobia exist among South African MSM: 10–15% reported “often/very often” and over 20% reported “sometimes” having feelings of internalized homophobia. A greater level of internalized homophobia was significantly associated with a lower level of education [Adjusted Odds Ratio = 2.2; 95% CI = 1.1–4.9], a higher level of HIV misinformation [AOR = 2.7; 95% CI: 1.3–5.3], bisexual identity (vs. homosexual) [AOR = 5.5; 95% CI: 2.5–12.0], and HIV-related conspiracy beliefs [AOR = 2.4; 95% CI: 1.02–5.8]. These findings contribute valuable information to our understanding of internalized homophobia in South Africa, highlighting the need to empower the gay community, promote self-acceptance of homosexual identity, and address conspiracy beliefs among MSM to reduce internalized homophobia and increase access to HIV prevention interventions.     

Accuracy of emergency nurses in assessment of patients’ pain

Pain is a common complaint in Emergency Departments. Inpatient studies have shown discrepancies between patients' and nurses' pain assessments. The accuracy of emergency nurse assessments of their patients' pain has not been well investigated. Using a 0 to 10 numeric rating scale (NRS), researchers asked patients to rate their pain intensity in triage. Separately, the triage nurse was asked to rate the patient's pain. This process was repeated with the same patients but different nurses after patients were taken back to a clinical area within the Emergency Department. At triage, patients' average pain intensity score was 7.5 +/- 2.2. The triage nurses' ratings were significantly lower at 5.1 +/- 2.4 (p <.001). In the clinical area, patients' scores were also significantly higher than nurses' at 7.7 +/- 2.2 and 4.2 +/- 2.3, respectively (p <.001). Differences between nurses' and patients' pain intensity scores depended on the patient's chief complaint. Considerable underestimation of patient's pain occurred in both triage and in the clinical area. Underestimation of patient's pain can have negative effects if appropriate treatment is withheld. Minimizing patient-nurse discrepancies in pain intensity ratings through careful evaluations and acceptance of the patient's self report of pain are important first steps in improving pain management in the Emergency Department.     

Concept analysis of intuition

From experience and observation of decision-making in intensive care units, the following has been observed in respect of clinical decision-making. Nurses in intensive care units take clinical decisions they can justify, and other decisions they cannot justify. Nurses in intensive care units sometimes refer to the unjustified clinical decisions as gut-feelings or intuition. The observation regarding clinical decision-making further indicates that clinical decision-making, based on intuition is effective and contributes to better and more complete problem-solving capabilities in intensive care units. From the preceding problem statement the following question arose, namely: What is intuition? The objective of the study is to analyze the concept intuition. A philosophical analytical research design was implemented in order to reach this objective. The concept intuition was analyzed by means of concept-analysis. The goal of concept analyses was to respectively describe the characteristics of intuition and developing a theoretical definition for the study regarding these characteristics. From the concept-analysis of intuition the following categories and characteristics of intuition realized namely situational factors of intuition, intuition as a process and intuition as a product. The situational factors of intuition refer to the factors that must be in place in order for intuition to occur, namely knowledge and experience, empathy, as well as incomplete data and uncertain situations. The second group characteristics of intuition has to do with the process of intuition, which is speedy, more synthetical-analogical than analytical, interpretative, holistic, irrational and goal-directed. The third category characteristics of intuition has to do with intuition as a product which include problem-solving and the rational justification of intuition by means of reflection.     

Validation of maternal self-report in retrospective studies

Case-control studies are frequently performed in prenatal and perinatal epidemiology. For data collection, these studies often rely on self‐administered questionnaires or personal interviews. Although of importance, validation of these measurement instruments received little attention in epidemiologic research so far. In this letter, we stress the need for more well‐conducted validation studies in the field of prenatal and perinatal epidemiology. In addition, we comment on a validation study that was previously published in this journal.     

Phylogeny of Lagos bat virus: challenges for lyssavirus taxonomy

Lagos bat virus (LBV) belongs to genotype 2 of the Lyssavirus genus. The complete nucleoprotein (N), phosphoprotein (P), matrixprotein (M) and glycoprotein (G) genes of 13 LBV isolates were sequenced and phylogenetically compared with other lyssavirus representatives. The results identified three different lineages of LBV. One of these lineages demonstrated sufficient sequence diversity to be considered a new lyssavirus genotype (Dakar bat lyssavirus). The suggested quantitative separation of lyssavirus genotypes using the N, P, M and G genes was also investigated using P-distances matrixes. Results indicated that the current criteria should be revised since overlaps between intergenotypic and intragenotypic variation occur.     

Biodistribution and absorbed radiation dose estimates of 99mTc-labeled dimercaptopropionyl human serum albumin.

The use of 99mTc-labeled red blood cells (RBC) for the evaluation of left ventricular function using equilibrium-gated blood-pool imaging suffers from several problems and potential risks. In this study, we estimated the absorbed radiation dose of 99mTc-labeled dimercaptopropionyl human serum albumin (DMP-HSA) as a potential alternative to 99mTc-RBC. METHODS: After the administration of 99mTc-DMP-HSA, whole-body imaging was performed up to 48 h after injection in five volunteers. The heart contents, liver and remainder of the body were used as source organs. Multicompartment modeling of the biodistribution was performed and absorbed radiation dose estimates for 99mTc-DMP-HSA were obtained using the Medical Internal Radiation Dose (MIRD) calculation. RESULTS: Residence times of 0.62 and 0.43 h were obtained for the heart contents and liver, respectively. Radiation dose estimates yielded an effective dose of 0.0055 mSv/MBq. CONCLUSION: 99MTC-DMP-HSA yielded absorbed radiation doses comparable with those of 99mTc-RBC. Therefore, the radiation properties of 99mTc-DMP-HSA are such that it can be used for clinical diagnostic studies.