Biomedical subjects

Robert H Glew

Publications and source records attributed to Robert H Glew.

24 records · Page 2Linked to original sources

PubMed2002

Evaluation of aminoaciduria in severely traumatized patients.

BACKGROUND: It has been documented in the literature that hypocalcemia, hypoaminoacidemia, and hyperaminoaciduria are sequelae of trauma. The aminoaciduria of patients with different types and severity of traumatic injuries was investigated. METHODS: Eight severely traumatized patients (ISS range, 20-43 years) and eight age-, gender-, and weight-matched controls were studied. Plasma and urine were collected 2.5-72 h after admission. Quantification of 28 amino acids in plasma and urine was performed by reversed-phase high-performance liquid chromatography. Urine concentrations of amino acids were indexed to creatinine. RESULTS: The patients' mean serum concentrations of 4 amino acids (arginine, threonine, isoleucine, and glutamine) were significantly decreased, 2 others (tryptophan and glutamic acid) were significantly increased, and 22 were unchanged (p-value< or =0.05). Fractional (urinary) excretion of 11 amino acids was increased in the patients. The patients' serum total calcium and albumin concentrations were decreased, but the mean ionized calcium concentration was not significantly different from the controls. CONCLUSIONS: The results of this study showed that aminoaciduria involving many amino acids is common for patients with different traumatic injuries and that the aminoaciduria is correlated with a reduction of the total serum calcium concentration.

Adult↗

PubMed2002

Fatty acid, amino acid, and trace mineral analyses of five weaning foods from Jos, Nigeria.

Five plant-based weaning foods (WF) (Dietrend, Jot-M, Soy, Ang, and Vic-T) locally prepared in Jos, Nigeria were analyzed by gas-liquid chromatography, reverse-phase high performance liquid chromatography, and atomic emission spectrometry with inductively coupled plasma to determine their fatty acid (FA), amino acid, and trace mineral contents, respectively. Results of these direct analyses were compared to expected values derived from food composition tables prepared by the United States Department of Agriculture (USDA). Additionally, results were compared against recommended nutrient values, using breast milk as the standard for FA content and recommended dietary allowances (RDA) for amino acid and mineral contents. The overall nutritional value of the five WF varied considerably and the quantities of particular nutrients determined by direct analysis differed markedly from those estimated using USDA food tables. Comparison of WF fatty acid composition relative to the RDA recommendations and a human milk standard revealed a much higher proportion of both linoleic (35-55 wt%) and alpha-linolenic acids (1%-7 wt%) relative to human milk lipids (11%-12% and 0.8%-0.9% wt, respectively); however, the WF were devoid of arachidonic acid and docosahexaenoic acid. Soy contained the highest amounts of linoleic acid (59.7 mg/g) and alpha-linolenic acid (7.46 mg/g) compared to the other four WF (10.2-41.0 and 0.35-3.18 mg/g, respectively). The linoleic acid/alpha-linolenic acid ratio was within the recommended range (5:1 to 10:1) in only Jot-M (10:1) and Soy (8:1). Dietrend, Vic-T and Ang, contained linoleic/alpha-linolenic ratios of 12:1, 29:1, and 82:1, respectively. The Soy weaning food would provide the most protein (24.3 g/day), based on an estimated daily intake of 65 g of weaning food by a normal six-month-old infant, compared to Jot-M (11.9 g/day), Dietrend (11.7 g/day), Ang (8.07 g/day), and Vic-T (7.26 g/day). The protein RDA for children up to 1 year of age is 13-14 g/day. Comparison of the mineral contents of the WF to the RDAs for various minerals indicated that all five would provide suboptimal amounts of calcium (16 to 250 mg/day) and zinc (1.42 to 3.56 mg/day) compared to respective RDAs of 400 mg/day and 5 mg/day. These data show that the Soy weaning food is an excellent source of linoleic acid and alpha-linolenic acid, as well as being a good source of high quality protein. Jot-M and Dietrend provide useful amounts of the essential FA; however, it is advisable to reevaluate the composition of Ang and Vic-T to find ways to improve the linoleic/alpha-linolenic ratio of each and increase their total protein content. These results document the shortcomings of using published food composition tables based on foods in America when devising weaning foods based on ingredients in another part of the world.

Amino Acids↗

PubMed2002

Bioelectrical impedance analysis of the body composition of children and adolescents with sickle cell disease.

OBJECTIVES: To examine the body composition of children and adolescents with sickle cell disease (SCD) using bioelectrical impedance analysis and to determine if the impedance parameters resistance, reactance, and phase angle are able to distinguish between subjects with SCD and age- and gender matched controls. STUDY DESIGN: Total body resistance and reactance were obtained for a total of 53 subjects with SCD (27 male and 26 female) between 10 and 18 years of age and 49 control subjects (23 male and 26 female). The fat-free mass, body cell mass, phase angle, and capacitance were also determined. Group comparisons were made using the 2-sample t test. RESULTS: Male subjects with SCD had significantly lower fat-free mass (37.5 +/- 8.8 vs 43.9 +/- 12.3 kg, P =.04), body cell mass (17.4 +/- 4.3 vs 21.7 +/- 5.8 kg,P =.005), and body fat (3.7 +/- 2.6 vs 6.6 +/- 4.7 kg, P =.008) compared with controls. No significant differences in any body composition components were found for the female subjects. Both male and female subjects had significantly lower phase angle measurements (P <.001 and.006, respectively) than their respective controls, indicating possible alterations in cell membrane properties because of an imbalance in membrane composition or function. CONCLUSIONS: Bioelectrical impedance analysis can be used to determine body composition differences in children with SCD. The phase angle may provide a useful method to monitor the efficacy of therapeutic interventions in patients with SCD.

Adolescent↗

PubMed2002

Hypocholesterolemia in Nigerian children with sickle cell disease.

Reports of circulating lipids of children with sickle cell disease (SCD) in Nigeria disagree on the question of whether these children are at increased risk of cardiovascular disease (CVD). We therefore analyzed the serum of 40 females and 37 males with SCD, age 5-19 years, and equal numbers of age-matched controls for total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, and homocysteine. Using bioelectrical impedance analysis, we documented a significant reduction in the per cent fat-free mass in the SCD males and increases in the per cent body fat in both the male and female children with SCD. Marked hypocholesterolemia was present in both genders (means, 100-102 mg/dl) and the LDL-cholesterol levels of the male and female subjects with SCD (54 mg/dl) were below the lower limit of the reference range (59-137 mg/dl). Serum triglycerides in the SCD subjects were in the middle of the reference range for children. Although the mean HDL-cholesterol levels of the SCD males (23.1 mg/dl) and females (24.5 mg/dl) were well below the lower limit of the reference range (35-84 mg/dl), respectively, the LDL-cholesterol/HDL-cholesterol ratios of the SCD subjects were not abnormal. The mean serum homocysteine concentrations of the male and female SCD subjects (9.4-9.6 micromol/l) were at the high end of the normal range. Collectively, these results indicate that children with SCD in northern Nigeria are not at increased risk of CVD. However, their marked hypocholesterolemia should be a cause of concern about the overall mortality and general well-being.

Adolescent↗

PubMed2002

The quality of in-house medical school examinations.

PURPOSE: Most medical schools test their students throughout the curriculum using in-house examinations written by the faculty who teach the courses. The authors assessed the quality of in-house examinations used in three U.S. medical schools. METHOD: In 1998, nine basic science examinations from the three schools were gathered and each question was subjected to quality assessment by three expert biomedical test developers, each of whom has had extensive experience in reviewing and evaluating questions for the United States Medical Licensing Examination (USMLE) Steps 1 and 2. Questions were rated on a five-point scale: 1 = tested recall only and was technically flawed to 5 = used a clinical or laboratory vignette, required reasoning to answer, and was free of technical flaws. Each rater made independent assessments, and the mean score for each question was calculated. Mean quality scores for National Board of Medical Examiners (NBME) who were trained question writers were compared with the mean scores for question writers without NBME training. The raters' quality assessments were made without knowledge of the test writers' training background or the study's hypothesis. RESULTS: A total of 555 questions were analyzed. The mean score for all questions was 2.39 +/- 1.21. The 92 questions written by NBME-trained question writers had a mean score of 4.24 +/- 0.85, and the 463 questions written by faculty without formal NBME training had a mean score of 2.03 +/- 0.90 (p <.01). CONCLUSIONS: The in-house examinations were of relatively low quality. The quality of examination questions can be significantly improved by providing question writers with formal training.

Education, Medical, Undergraduate↗

PubMed2002

Serum lipid profiles and risk of cardiovascular disease in three different male populations in northern Nigeria.

The Fulani of northern Nigeria are indigenous semi-nomadic pastoralists whose diet consists largely of dairy products. Despite their consumption of relatively large amounts of saturated fats, an earlier study showed that their total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and serum triglyceride levels fall within the reference range of values for North Americans. Men in the cities of Jos and Abuja, two populations who also reside in northern Nigeria, differ from the Fulani with regard to diet and activity level. Males in both Jos and Abuja have diets consisting of high protein or carbohydrate and are more sedentary than the Fulani subjects. The main aims of the study were to measure the concentrations of various lipids in the blood serum of male urban dwellers in Jos and Abuja and to compare their blood lipid profiles with those of the rural Fulani (mean age 33.9 years). Blood serum samples from 118 men in Jos (mean age 37.9 years) and 77 men in Abuja (mean age 34.4 years) were analyzed for total cholesterol, triglycerides, LDL, HDL, homocysteine, folate, and vitamin B12. In addition to height and weight, systolic and diastolic blood pressures were measured. The mean total cholesterol, triglyceride, HDL and LDL values for the three groups of subjects fell within or close to the accepted range of values for North Americans. However, the Fulani males had HDL values (mean, 33.9 mg/dL) below the range of values prescribed for North Americans (>40 mg/dL). Moreover, the Fulani men and the men in Abuja had a total cholesterol/ HDL ratio of 4.2 and 4.0 respectively, which exceed the accepted value (< or =3.5) prescribed by the Columbia University. In all three populations, the incidence ofhomocysteinaemia (serum homocysteine > 12.4 micromol/L) was very high. Their mean homocysteine levels ranged from 14.7 to 16.7 pmol/L and could not be accounted for by folate or vitamin B12 status. The mean blood pressures of the Abuja (127/77 mm Hg) and the Fulani (120/74 mm Hg) men were within the normotensive range (<130/85 mm Hg). However, the mean blood pressures of the Jos males (131/85 mm Hg) indicated borderline hypertension. These data indicate that, with regard to serum lipids, urban and rural adult Nigerian males have generally favourable risk factors for cardiovascular disease when compared with healthy North Americans. All three sub-populations, however, have levels of homocysteine that are cause for concern vis-à-vis their overall health status.

Adult↗