Search PubMed⌕ Search

Biomedical subjects

M Woods

Publications and source records attributed to M Woods.

At least 109 records · Page 6Linked to original sources

Food uses and health effects of corn oil.

This review of corn oil provides a scientific assessment of the current knowledge of its contribution to the American diet. Refined corn oil is composed of 99% triacylglycerols with polyunsaturated fatty acid (PUFA) 59%, monounsaturated fatty acid 24%, and saturated fatty acid (SFA) 13%. The PUFA is linoleic acid (C18:2n-6) primarily, with a small amount of linolenic acid (C18:3n-3) giving a n-6/n-3 ratio of 83. Corn oil contains a significant amount of ubiquinone and high amounts of alpha- and gamma-tocopherols (vitamin E) that protect it from oxidative rancidity. It has good sensory qualities for use as a salad and cooking oil. Corn oil is highly digestible and provides energy and essential fatty acids (EFA). Linoleic acid is a dietary essential that is necessary for integrity of the skin, cell membranes, the immune system, and for synthesis of icosanoids. Icosanoids are necessary for reproductive, cardiovascular, renal, and gastrointestinal functions and resistance to disease. Corn oil is a highly effective food oil for lowering serum cholesterol. Because of its low content of SFAs which raises cholesterol and its high content of PUFAs which lowers cholesterol, consumption of corn oil can replace SFAs with PUFAs, and the combination is more effective in lowering cholesterol than simple reduction of SFA. PUFA primarily lowers low-density-lipoprotein cholesterol (LDL-C) which is atherogenic. Research shows that PUFA has little effect on high-density-lipoprotein cholesterol (HDL-C) which is protective against atherosclerosis. PUFA generally improves the ratio of LDL-C to HDL-C. Studies in animals show that PUFA is required for the growth of cancers; the amount required is considered to be greater than that which satisfies the EFA requirement of the host. At this time there is no indication from epidemiological studies that PUFA intake is associated with increased risk of breast or colon cancer, which have been suggested to be promoted by high-fat diets in humans. Recommendations for minimum PUFA intake to prevent gross EFA deficiency are about 3% of energy (en%). Recommendations for prevention of heart disease are 8-10 en%. Consumption of PUFA in the United States is 5-7 en%. The use of corn oil to contribute to a PUFA intake of 10 en% in the diet would be beneficial to heart health. No single source of salad or cooking oil provides an optimum fatty acid (FA) composition. Many questions remain to be answered about the relation of FA composition of the diet to various physiological functions and disease processes.

Animals↗

Antibiotic prophylaxis in cardiothoracic surgery: results of a second survey.

The use of prophylactic antimicrobials in cardiothoracic surgery has become an accepted medical practice. The choice of drug and the duration of therapy varies among institutions. In 1985, we conducted a telephone survey to determine the choice of prophylactic antimicrobials in cardiothoracic surgery programs across the U.S. We recently conducted this survey for a second time. In our 1988 survey, 51 hospitals responded, with 34 (67%) having a standard antimicrobial regimen. Of all hospitals surveyed, first-generation cephalosporins were the most commonly used agents. First-generation cephalosporins were employed in 33 (48.4%) hospitals, cefamandole in 13 (19.1%), cefuroxime in nine (13.2%), vancomycin in three (4.4%), and vancomycin plus gentamicin in two (2.9%). A variety of other agents were employed by one of the remaining hospitals. Fourteen (27%) hospitals had automatic stop orders for antimicrobial prophylaxis in this indication. Ten (19.6%) institutions had changed the antimicrobial agent(s) used for prophylaxis in the last year. The results of this survey indicate that most hospitals continue to use first-generation cephalosporins for antimicrobial prophylaxis in cardiothoracic surgery, but there is considerable variation among institutions.

Anti-Bacterial Agents↗

Results of a randomized feasibility study of a low-fat diet.

A 2-year randomized clinical trial was conducted to test whether free-living women aged 45 to 69 years can reduce the fat content of their diet from the typical US level of approximately 39% to 20% of energy from fat, using readily available foods, when given nutritional and behavioral counseling and social support. Three clinical units randomized 303 selected volunteers into intervention (low-fat eating plan) or control (customary diet) groups. The two groups were comparable at baseline. The intervention group received nutrition instruction and behavioral counseling largely in permanent groups of 12 to 15 participants meeting weekly, then biweekly, and finally monthly. At 6 months, they had substantially reduced the mean proportion of total energy from fat from 39.1% to 20.9%, compared with the control group's nonsignificant reduction from 39.0% to 38.1%. At 12 and 24 months, they sustained the reduction of energy from fat. Weight loss and plasma cholesterol level changes in the intervention group supported the self-recorded dietary intake changes. Attendance at intervention sessions averaged 75% during the first 6 months and, subsequently, 60% to 70%. Four-day food records for the randomized women were obtained at 6 and 12 months from approximately 95% and at 24 months from 87%. A clinical trial of a low-fat diet is feasible in women.

Aged↗

MMPI F-K index among hospitalized Vietnam veterans.

The F-K index of the MMPI has been used as a marker of symptom overreporting. One population for which previous research has shown this pattern is Vietnam in-country veterans with PTSD. This study assessed the F-K index on 515 inpatients: 329 Vietnam in-country and 186 Vietnam-era patients. Normative data on psychiatric inpatients were presented. Also, a special MMPI subscale (MMPI-PTSD), a measure to identify PTSD among these veterans, was used. Results showed that all Vietnam veterans, especially in-country veterans, overreport symptoms to a high degree. The overall mean for in-country vets was 7.3. Also, when the special MMPI-PTSD subscale was used, a vast majority of in-country veterans who were in the PTSD range had high F-K index scores. Dissimulation as a symptom of PTSD was discussed.

Adult↗

Plasma lipoprotein cholesterol and endogenous sex hormones in healthy young women.

Relationships between plasma levels of lipoproteins and sex hormones were studied in 24 healthy premenopausal women with no risk factors for coronary heart disease. The women were carefully selected to remove the effects of other environmental factors, such as smoking, drugs, alcohol, and exercise, which are known to influence lipid metabolism. They all ate precisely the same Western-style diet for 1 to 2 weeks before blood samples were obtained in the follicular phase of their menstrual cycle. After adjusting for other hormones by multiple regression, significant positive partial correlations were seen between high density lipoprotein cholesterol (HDL-C) and protein bound estradiol (r = .57, P = .02), as well as between very low density lipoprotein cholesterol (VLDL-C) and protein bound estradiol (r = .63, p = .01). A significant negative partial correlation was seen between VLDL-C and free estradiol (r = -.65 P = .01). Conversely, low density lipoprotein cholesterol (LDL-C) levels were negatively correlated with protein bound estradiol (r = -.77, P less than .001) and positively correlated with free estradiol (r = .71, P less than .001). No associations between plasma lipoproteins and testosterone were seen; however, androstenedione was positively correlated with VLDL-C (r = .59, P = .01). These findings show a close link between plasma lipoproteins and sex hormones, and may help to explain the lower risk of coronary heart disease in women.

Adult↗

Intravenous meperidine during labor: a randomized comparison between nursing- and patient-controlled administration.

Preliminary reports about patient-controlled analgesia during labor have been promising. The purpose of this investigation was to compare our experience with meperidine given intravenously by the patient versus by a nurse. Sixty-four healthy women beginning active labor (cervical dilation 3 cm) at term were randomly assigned to either self-administer a 10-mg dose as often as every 20 minutes or have a nurse administer 25-50 mg every 3 hours as requested. The total meperidine dose and consumption rates were greater when administered by the patient than by a nurse. Maternal side effects occurred with similar frequency in both groups, and pain relief was judged to be equivalent. Maternal and umbilical serum concentrations of meperidine at delivery increased in the patient-controlled group if active labor lasted longer than 2 hours. Neonatal naloxone therapy was used more often when meperidine was administered by the patient than by a nurse (five of 31, 16%, versus three of 33, 10%, respectively). Self-administration of intravenous meperidine by the laboring patient was not found to be advantageous over nursing administration, and may pose an increased threat to the infant.

Adult↗

The longitudinal effects of growth on the Wits appraisal.

The longitudinal changes occurring between the ages of 4 and 24 years in the Wits appraisal and its component parts were evaluated in 40 persons. Contrary to what may have been believed previously, the Wits appraisal was not found to remain stable throughout the growth period. When the findings of the Wits appraisal were studied in individual subjects, there was a wide range of variation. Real changes in the Wits appraisal were found to be disguised clinically by the differential sagittal growth of pogonion in relation to B point, especially in male subjects. Furthermore, the appraisal was found to be affected profoundly by changes occurring in the angulation of the occlusal plane. It was concluded that if the Wits appraisal is to be used, it should be used in conjunction with other methods of assessment of apical base discrepancies and with due regard for the likely effects of changes in its component parts.

Adolescent↗

Intra-ocular pressure changes during rapid sequence induction of anaesthesia. A comparison between thiopentone and suxamethonium and thiopentone and atracurium.

The changes in intra-ocular pressure associated with two different anaesthetic induction and tracheal intubation techniques were compared (n = 30). After pre-oxygenation, Group A received thiopentone (5 mg/kg) followed by suxamethonium (1.5 mg/kg), both within 25 seconds, and Group B atracurium (0.5 mg/kg) followed by thiopentone (5 mg/kg) again both within 25 seconds. Tracheal intubation occurred after one minute in Group A and 2 minutes in Group B to allow for full paralysis. In Group A intra-ocular pressure did not alter significantly from baseline and the maximum increase was only 0.93 mmHg. The statistical type II error risk was consistently below 55% and all 95% confidence limits included negative values. Intra-ocular pressure in Group B was consistently lower than baseline (p less than 0.05) but with a longer induction-intubation interval. These results therefore provide valuable information about the 'balance of risks' when choosing a muscle relaxant for an inadequately starved patient with a penetrating eye injury.

Adolescent↗

The pattern electroretinogram: a long-term study in acute optic neuropathy.

We report a 2-year prospective study of the electroretinographic response to reversal of checkerboard patterns (P-ERG) obtained in 63 eyes with acute optic nerve lesions. The aim of the study was to document the value of P-ERG regarding diagnosis and prognosis of four types of optic neuropathy: optic neuritis, compressive or hereditary optic atrophy, and traumatic optic neuropathy. We documented visual loss by neuro-ophthalmologic examination and recorded pattern-reversal visual evoked potentials (P-VEP). The initial P-ERG was normal to large- and medium-sized checks in 89% and the P-VEP abnormal in 94% of eyes with acute optic nerve lesions. Forty-six eyes were followed for up to 2 years. Two groups emerged. Group A (n = 17) gradually and permanently had significant reduction of the P-ERG to three separate check sizes. All 17 had no improvement in acuity better than 20/100, retained centrocecal scotomas, and developed optic atrophy. In group B (n = 29) the P-ERG remained within normal limits to one or more check sizes. Twenty-two of these eyes recovered acuity to 20/25 or better and had resolution of the field defect. The data showed that P-VEP was superior to P-ERG in diagnosis of acute and chronic optic nerve lesions. However, significant reduction of the b-wave of the P-ERG to three separate check sizes correlated closely with failure of visual recovery and the eventual development of severe optic atrophy, suggesting a prognostic value for P-ERG in optic neuropathy.

Adolescent↗

Spectral and kinetic studies on the binding of trithiomolybdate to bovine and canine serum albumin in vitro: the interaction with copper.

Spectral studies showed that copper and trithiomolybdate participated in a three-way interaction with bovine and canine serum albumin. The interaction with the proteins was affected by increased pH and ionic strength. Kinetic studies of binding equilibria indicated that [35S] trithiomolybdate bound to both albumins at a single site. The affinity of the site, but not the capacity of the protein, was increased by copper. It was concluded that the site was distinct from the N-terminal copper (and nickel) binding site, which is present on BSA but absent from CSA. Whether or not the N-terminal site has a role in copper transport is discussed. Reversible thiomolybdate-copper-protein interactions of this type may play a fundamental role in the pathogenesis of Mo-induced syndromes, since as the normal binding patterns are perturbed the interprotein equilibria are altered and the copper distribution patterns are modified.

Animals↗

Dietary molybdenum as a putative copper antagonist in the horse.

Four horses were stabled and fed a diet of hay ad libitum, and 2 kg oats per animal per day, for a month. The basic diet was then supplemented with molybdenum, at a rate of 20 mg/kg dry matter for 4.5 months. For one month of this period the diet was supplemented also with sulphur at a rate of 1.2 g/kg dry matter. Analyses of jugular blood samples, obtained at intervals varying between two and 20 days, showed no evidence of a decline in total plasma copper or of an increased proportion of trichloroacetic acid (TCA) insoluble copper in plasma over this period. In separate studies, two other horses were given 99molybdenum (molybdate, 20 to 28 mg Mo, 4 mCi per animal) per os, initially while being fed the basic diet and later while maintained on the molybdenum supplemented diet. 99Molybdenum appeared rapidly in plasma, but the radioactivity was then quickly cleared (half-life 7 to 10 h). The 99molybdenum present was identified as (99Mo)-molybdate. There was no evidence of the persistent, protein-bound (99Mo)thiomolybdates which appear in ruminants. These studies indicate that increased dietary molybdenum is unlikely to interfere with copper metabolism in horses.

Administration, Oral↗

The effect of a low fat diet on estrogen metabolism.

Women who consume a diet low in fat are at lower risk for breast cancer than women whose diet is relatively high in fat. To investigate the effects of a low fat diet on estrogen metabolism, six normal young women were studied while eating a Western-style high fat diet and again after 2 months of consuming a defined low fat diet. Both studies involved the simultaneous administration of [3H]estradiol [( 3H]E2) orally and [14C]E2 iv and the subsequent collection of multiple blood samples and urine for 96 h. The blood samples were analyzed for radioactivity as estrone (E1), E2, their glucuronides, and E1 sulfate. An aliquot of the pooled 96-h urine was analyzed for radioactivity as the glucuronides and sulfates of E1, E2, estriol, 16 alpha-hydroxyestrone (16 alpha-OHE1), and the catechol estrogens, i.e. 2-hydroxy and 2-methoxy metabolites of E1 and E2. The low fat diet resulted in a consistent and significant (P less than 0.05) decrease in urinary excretion of both 16-hydroxylated metabolites, estriol and 16 alpha-OHE1, expressed as a percentage of administered dose of [3H]E2 and [14C]E2, and an increase in the excretion of the catechol estrogens. These changes in metabolite excretion were not, however, mirrored by changes in the MCRs or conversion ratios of either [3H]E2 or [14C]E2. Thus, while neither the clearance of E2 from the blood nor its absorption from the intestinal tract was altered by a relatively short term decrease in dietary fat, there was a shift in the pattern of urinary metabolites away from the purported carcinogenic estrogen (16 alpha-OHE1) and toward the less active catechol estrogens. This may represent an important mechanism whereby low fat diets decrease the risk of breast cancer.

Adult↗

Effect of menstrual cycle phase on plasma lipids.

The effect of endogenous sex hormone fluctuations on plasma lipoprotein levels was studied in 15 young women. Plasma samples were taken during the follicular, ovulatory, and luteal phases of the menstrual cycle while the women were consuming a defined diet, similar to the average American diet. No significant effect of menstrual cycle phase on plasma total cholesterol or cholesterol lipoprotein subfraction levels was found; however, a 34% increase in total plasma triglycerides associated with an increased very low density lipoprotein triglyceride fraction was found during the ovulatory phase. These data indicate that menstrual cycle phase can have a significant effect on plasma triglyceride levels, but not on plasma cholesterol or lipoprotein fractions.

Adult↗