PubMed Health⌕ Search

Biomedical subjects

M Ellis

Publications and source records attributed to M Ellis.

At least 73 records · Page 4Linked to original sources
PubMed2000

Risk factors for neonatal encephalopathy in Kathmandu, Nepal, a developing country: unmatched case-control study.

OBJECTIVE: To determine the risk factors for neonatal encephalopathy among term infants in a developing country. DESIGN: Unmatched case-control study. SETTING: Principal maternity hospital of Kathmandu, Nepal. SUBJECTS: All 131 infants with neonatal encephalopathy from a population of 21 609 infants born over an 18 month period, and 635 unmatched infants systematically recruited over 12 months. MAIN OUTCOME MEASURES: Adjusted odds ratio estimates for antepartum and intrapartum risk factors. RESULTS: The prevalence of neonatal encephalopathy was 6.1 per 1,000 live births of which 63% were infants with moderate or severe encephalopathy. The risk of death from neonatal encephalopathy was 31%. The risk of neonatal encephalopathy increased with increasing maternal age and decreasing maternal height. Antepartum risk factors included primiparity (odds ratio 2.0) and non-attendance for antenatal care (2.1). Multiple births were at greatly increased risk (22). Intrapartum risk factors included non-cephalic presentation (3.4), prolonged rupture of membranes (3.8), and various other complications. Particulate meconium was strongly associated with encephalopathy (18). Induction of labour with oxytocin was associated with encephalopathy in 12 of 41 deliveries (5.7). Overall, 78 affected infants (60%) compared with 36 controls (6%) either had evidence of intrapartum compromise or were born after an intrapartum difficulty likely to result in fetal compromise. A concentration of maternal haemoglobin of less than 8.0 g/dl in the puerperium was significantly associated with encephalopathy (2.5) as was a maternal thyroid stimulating hormone concentration greater than 5 mIU/l (2.1). CONCLUSIONS: Intrapartum risk factors remain important for neonatal encephalopathy in developing countries. There is some evidence of a protective effect from antenatal care. The use of oxytocin in low income countries where intrapartum monitoring is suboptimal presents a major risk to the fetus. More work is required to explore the association between maternal deficiency states and neonatal encephalopathy.

Body Height↗
PubMed2000

Autoimmune thyroid disease and antiphospholipid antibodies.

OBJECTIVE: Autoimmune thyroid disease (ATD) is associated with circulating autoantibodies reactive with epitopes on thyroid tissue and that are thought to be pathogenic in the development of these diseases. Antiphospholipid antibodies (APLA) are a family of immunoglobulins that recognize a variety of plasma proteins in association with anionic phospholipids. These antibodies may lead to a number of clinical syndromes including venous and arterial thromboses, thrombocytopaenia, and recurrent fetal loss. We have studied the prevalence of APLA in patients with ATD and have determined the prevalence of the APLA syndrome among APLA-positive patients. DESIGN: The study was a retrospective survey of patients with autoimmune thyroid disease attending the endocrinology clinic of a tertiary care academic hospital. PATIENTS AND MEASUREMENTS: One hundred and thirty patients with autoimmune thyroid disease from the endocrinology clinic at our hospital were studied. 84% had chronic thyroiditis and 16% had Graves' disease. Free T4 and thyroid stimulating hormone (TSH) levels, antimicrosomal and antithyroglobulin antibodies, and an antiphospholipid antibody test were performed on all subjects. RESULTS: 43% of patients with chronic thyroiditis and 43% of patients with Graves' disease were APLA positive, with an overall rate of 43% APLA positivity among patients with ATD. Of the 56 patients that were APLA positive, forty-eight (86%) had APLA of the IgG subtype, four (7%) had IgM antibodies, and nine (16%) had both IgG and IgM antibodies. None of the patients had clinical evidence of the APLA syndrome. CONCLUSIONS: We conclude that the prevalence of APLA in ATD is increased compared to healthy individuals but that this is likely to be an epiphenomenon. However, prolonged follow up is necessary in order to determine the true clinical significance of these antibodies in ATD patients.

Antibodies, Antiphospholipid↗
PubMed2000

Amphotericin B preparations: a maximum tolerated dose in severe invasive fungal infections?

Availability of lipid formulations of amphotericin B has opened up the possibility of treating invasive fungal infections in immunocompromised patients with high doses of this antifungal agent. Evidence is emerging to suggest that lipid formulations may have heightened efficacy compared to conventional amphotericin B. The issue of optimal dosage has been a neglected area. This article reviews published data accrued from clinical, open-label, salvage, and other studies, and finds little support that the use of high doses of lipid formulations are more efficacious than lower doses. The response rates for invasive fungal infection from most studies are predictably around 56%, irrespective of the lipid formulation and dose used. Animal models provide evidence that low doses of a lipid formulation are as successful in reducing fungal dissemination and in prolonging survival as higher doses, although concomitant tissue fungal eradication is not as effectively achieved by the lower doses (survival-mycologic eradication dissociation). Kinetic studies performed in the clinically relevant setting of critically ill patients give further support to the use of low doses, since levels of liposomal amphotericin B at all dosages between 1 and 4 mg/kg/day are similar and above maximum inhibitory concentrations for commonly encountered fungi. There has only been one prospective randomised study designed with the primary end-point of comparing two dosages of an amphotericin B lipid formulation on clinical response and survival. That European Organization for Research and Treatment of Cancer (EORTC) study concluded that liposomal amphotericin B given at 1 mg was as efficacious as 4 mg/kg/day in treating neutropenic patients with invasive pulmonary aspergillosis. There are a multitude of unanswered questions concerning dosing, and their answers are confounded by difficulties in performing clinical trials and the multiplicity of factors other than antifungal chemotherapy that influence outcome. Maximum tolerated dose studies using existing lipid formulations, or perhaps with the newer formulations such as pegylated immunoliposomal amphotericin B, could be performed to shed light on this difficult area.

Amphotericin B↗
PubMed2000

Stillbirths and neonatal encephalopathy in Kathmandu, Nepal: an estimate of the contribution of birth asphyxia to perinatal mortality in a low-income urban population.

We describe a prospective cross-sectional survey over a 12-month period in the principal maternity hospital of Kathmandu, Nepal, where over 50% of the local population deliver. The study aim was to estimate the contribution of birth asphyxia to perinatal mortality in this setting. During 1995, there were 14,371 livebirths and 400 stillbirths, a total stillbirth rate of 27 per 1000 total births. The fresh term (2000 g or more) stillbirth rate was 8.5 per 1000 total births [95% CI 7.1, 10.1]. Ninety-two cases of neonatal encephalopathy (NE) affecting term infants were detected (excluding those due to congenital malformations, hypoglycaemia and early neonatal sepsis). The birth prevalence of NE was 6.4 per 1000 livebirths [95% CI 5.2, 7.8]. There was evidence of intrapartum compromise in 63 (68%) of the cases of NE and 65 (76%) of the stillbirths, but only in 12 (12%) of controls. The cause-specific early neonatal mortality rate for NE was 2.1 per 1000 livebirths [95% CI 1.4, 3.0]. Combining the NE deaths and fresh stillbirths gives an upper estimate for term birth asphyxia perinatal mortality rate of 10.8 per 1000 total births [95% CI 9.2, 12.6], 24% of all perinatal deaths before hospital discharge. This study suggests that birth asphyxia remains an important cause of perinatal mortality in developing countries. The paper discusses the pros and cons of different strategies to reduce birth asphyxia in low-income countries.

Asphyxia Neonatorum↗
PubMed2000

Deliberate sulphonylurea poisoning mimicking hyperinsulinaemia of infancy.

A 6 month old child presenting with seizures was found to be hypoglycaemic secondary to hyperinsulinism. A family history of type II diabetes prompted estimation of sulphonylurea in the baby's blood, which was found to be high. A multidisciplinary case conference concluded that the sulphonylurea ingestion was likely to be the result of Munchausen syndrome by proxy. When investigating hypoglycaemia of infancy this possibility should be considered.

Diagnosis, Differential↗
PubMed2000

Epidemiology.

Invasive fungal infections have emerged as important causes of hospital related morbidity and mortality. They are increasingly seen in patients not previously considered at risk, e.g. patients on an intensive care unit. Candida albicans and Aspergillus spp. are the most common pathogens, posing challenges in epidemiology, control and treatment.

Aspergillosis↗
PubMed2000

Clinical and laboratory diagnosis.

Clinical diagnosis of invasive fungal infections demands a high clinical acumen, but both under- and over-diagnosis are common. Laboratory mycological tests have traditionally been limited by a range of complications. Development of methodologies to detect fungal-specific immunoglobulins, cell wall antigens and nucleic acid have improved dramatically in recent years.

Aspergillosis↗
PubMed2000

Management.

The management of invasive fungal infection utilizes a variable multidisciplinary approach involving antifungals, appropriate surgery and immuno-correction. Conventional amphotericin B has been the mainstay of treatment but newer pathogens and poor outcomes has led to new formulations of this drug as well as to new and novel antifungals.

Amphotericin B↗
PubMed2000

Feeder location did not affect performance of weanling pigs in large groups.

Crossbred pigs weaned at 17 d of age (n = 1,760; mean initial BW = 5.6 +/- 0.7 kg) were used in two 4-wk trials (four replicates per trial) to evaluate the effects of three pen designs on pig performance. The designs were 1) large group size (100 pigs/pen) with five two-sided feeders in a single, central location in the pen; 2) large group size (100 pigs/pen) with five two-sided feeders in multiple (five) locations in the pen; and 3) small group size (20 pigs/pen) with a single two-sided feeder in a central location in the pen. Each feeder provided two 20.3-cm-wide feeding places on each side. Pigs had free access to feed and water. Feeder-trough space (4 cm/pig) and floor-area allowance (0.17 m2/pig) were the same for all treatments. Pigs in the large-group treatments were lighter (15.6 and 15.6 vs 16.0 kg; P < 0.01) at the end of wk 4 and had lower ADG (358 and 357 vs 373 g; P < 0.01) and ADFI (510 and 521 vs 544 g; P < 0.01) during wk 2 through 4 than pigs in small groups. Gain:feed ratio was similar (P > 0.05) for all treatment groups throughout the study. For large groups, feed disappearance from each of the five feeders was similar (P > 0.05) for both multiple- and single-location treatments. In summary, large group size reduced pig growth performance, but the approach to providing multiple feeding locations that was employed in this experiment did not increase feed intake or growth performance of pigs in the large groups.

Animal Feed↗
PubMed2000

The effect of the Halothane and Rendement Napole genes on carcass and meat quality characteristics of pigs.

The objective of this study was to determine the effects of the Halothane (N) and Rendement Napole (RN) genes on carcass and meat quality characteristics in pigs. Halothane and RN carrier (Nn/RN- rn+) Hampshire boars (n = 4) were mated to dams that were homozygous for the normal allele of both genes (NN/rn+ rn+) to produce progeny of four genotypes: 1, NN/rn+ rn+ (n = 31); 2, Nn/rn+ rn+ (n = 27); 3, NN/RN- rn+) (n = 30); and 4, Nn/RN- rn+ (n = 23). A DNA test was used to determine Halothane genotype, and longissimus glycolytic potential was used to predict the RN genotype. Pigs were reared under standard conditions to approximately 120 kg live weight and slaughtered at a commercial plant, and carcass characteristics and meat quality were evaluated. Halothane carriers (Nn/ _ _), in comparison to Halothane normal (NN/_ _) pigs, had shorter carcasses, lower longissimus ultimate pH, higher Minolta L* and b* values, and greater drip loss. Rendement Napole gene carriers (_ _/RN- rn+) had higher L* and b* values and drip and cooking loss and lower longissimus ultimate pH than homozygous recessive animals (_ _/rn+ rn+). There were Halothane x RN genotype interactions (P < 0.05) for subjective color, firmness, and marbling scores, and for shear force. Animals that were normal for both genes (NN/rn+ rn+) had the highest subjective scores for color (2.60, 1.88, 1.85, and 1.95, SE = 0.181, P < 0.05), firmness (2.53, 2.03, 2.10, and 1.89, SE = 0.182, P < 0 .05), and marbling (2.11, 1.44, 1.53, and 1.55, SE = 0.153, P < 0 .05) for genotypes 1, 2, 3, and 4, respectively, suggesting darker, firmer muscle with a higher level of marbling for this genotype. Shear force was highest for Nn/rn+ rn+ animals (3.83, 4.41, 3.79, and 3.70, respectively, SE = 0.172, P < 0.05). Gilts had less s.c. backfat thickness, greater longissimus muscle area, and lower subjective marbling scores than barrows. There was no effect (P > 0.05) of gender on other meat quality traits. This study illustrates the negative effects of the Halothane and RN genes on fresh pork quality and suggests that in combination the detrimental effects of the two genes are additive for ultimate pH, objective color, and water-holding capacity.

Alleles↗
PubMed2000

Effect of dietary lysine level and environmental temperature during the finishing phase on the intramuscular fat content of pork.

This study was designed to investigate the effects of dietary lysine level on the intramuscular fat content of the longissimus in finishing pigs reared at two environmental temperatures. Seventy-two hybrid gilts were individually penned and given ad libitum access to either a diet formulated to meet their lysine requirement (6.4 g/kg lysine) or a lysine-deficient diet (4.8 g/kg). Pigs were held at one of two environmental temperatures (thermoneutral [18 degrees C] or hot [32 degrees C]). The study was carried out between approximately 90 and 126 kg live weight; pigs in the thermoneutral and hot environments were on test for 5 and 7 wk, respectively. There were no interactions between dietary lysine level and environmental temperature. Dietary lysine content did not influence feed intake or average daily gain; however, pigs on the lysine-deficient diet had a poorer gain:feed ratio than those fed to requirement (P < .01). High environmental temperature decreased feed intake (P < .001) and average daily gain (P < .01) but improved gain:feed ratio (P < .01). Backfat at the 10th rib was increased and loin eye area and estimated percentage lean in the carcass were decreased for pigs on the lysine-deficient diet. The higher environmental temperature resulted in an increase in carcass length but had no effect on other carcass measurements or intramuscular fat. Feeding the lysine-deficient diet resulted in an increase of .55 percentage unit in longissimus intramuscular fat content (P < .01); however, there was no difference in subjective marbling scores between the diets. Warner-Bratzler shear force values were not affected by dietary lysine level or environmental temperature. Results from this study suggest that feeding of lysine-deficient diets at the end of the finishing period can increase intramuscular fat deposition under thermoneutral and hot conditions.

Adipose Tissue↗
PubMed2000

Frequency of the Rendement Napole RN- allele in a population of American Hampshire pigs.

A total of 204 purebred Hampshire pigs were obtained from 23 breeders. These animals were the progeny of 41 sires and 123 dams. A sample of purebred Yorkshire (n = 24) pigs were also used in the study. Animals were classified by glycolytic potential determined on a live-animal longissimus muscle biopsy sample. Hampshire pigs (n = 176) with glycolytic potential greater than 185 micromol/g (x = 238.8 micromol/g; SD = 29.54) were classified as heterozygous or homozygous for the dominant RN- allele (RN-rn+ or RN-RN-, respectively), whereas cohorts (n = 28) with glycolytic potential less than 185 micromol/g (x = 141.3 micromol/g; SD = 24.48) were considered as homozygous normal (rn+rn+). All Yorkshire pigs (n = 24) had a mean glycolytic potential level of 146.1 micromol/g (SD = 20.18) and were considered as homozygous normal (rn+rn+). The Hardy-Weinberg equilibrium yielded frequencies of .630 and .370 for the dominant RN- allele and normal rn+ alleles in the Hampshire population, respectively, and genotypic frequencies of .397 (RN-RN-), .466 (RN-rn+), and .137 (rn+rn+). Hampshires with glycolytic potential > or = 185 micromol/g had significantly lower longissimus muscle ultimate pH, intramuscular fat, subjective marbling scores, and percentage of protein (P < .001) and had greater longissimus muscle percentage of moisture (P < .001), drip loss (P < .01), and cooking loss (P < .001) than rn+rn+ Hampshires and Yorkshires. These data suggest the RN- allele exists at a high frequency within the American Hampshire breed. Higher glycolytic potential levels, which accompany the allele, may cause decreased meat quality.

Alleles↗
PubMed2000

Group size and floor-space allowance can affect weanling-pig performance.

Crossbred weanling piglets (n = 1,920; mean initial BW, 5.3 +/- .7 kg) were used in two 9-wk trials employing a randomized block design in a 2 x 2 factorial arrangement of treatments to determine effects of group size (20 [Small = S] or 100 [Large = L] pigs/pen) and floor-space allowance (calculated requirement [CR] or calculated requirement less 50% of estimated "free space" [CR-50]) on growth performance. Free space was estimated for each group size. From wk 1 through 4 after weaning, S and L groups at CR were allowed a floor space of .17 m2/pig, and at CR-50, S and L groups were allowed .15 m2/pig and .13 m2/pig, respectively. From wk 5 through 9 after weaning, all CR treatment pigs were provided a floor space of .38 m2/pig, and for the CR-50 treatment, S and L pigs were allowed .32 m2/pig and .28 m2/pig, respectively. Piglets had free access to feed and water. Feeder-trough space per pig was the same for both group sizes. Feed-intake data were collected for only wk 1 through 4. Group size by floor-space allowance interactions (P < .05) were found for gain/feed ratio (G/F) for wk 1 and wk 2 through 4, but not for wk 1 through 4. Piglets in L groups were lighter (P < .001) at the end of wk 1, 4, and 9 by 2, 4, and 5%, respectively, and had lower ADG (6%; P < .001) throughout the trial than S piglets. During wk 1 through 4, feed intake was lower (7%, P < .001) in L piglets than in S piglets, but G/F was similar (P > .05). Piglets in CR groups had greater ADG (5%; P < .01) throughout the trial, with a greater G/F (P < .05) for wk 1 through 4, and were heavier (P < .01) than those in CR-50 groups at the end of wk 4 (3%) and 9 (4%). Pigs in L groups had a greater within-pen coefficient of variation in BW at the end of wk 9 than pigs in S groups. Large groups and reduced floor-space allowance reduced piglet growth performance in the nursery.

Animals↗
PubMed2000

Molecular strategies for improving waterlogging tolerance in plants.

Plants, like animals, are obligate aerobes, but due to their inability to move, have evolved adaptation mechanisms that enable them to survive short periods of low oxygen supply, such as those occurring after heavy rain or flooding. Crop plants are often grown on soils subject to waterlogging and many are sensitive to waterlogging of the root zone. The combination of unfavourable weather conditions and suboptimal soil and irrigation techniques can result in severe yield losses. The molecular basis of the adaptation to transient low oxygen conditions has not been completely characterized, but progress has been made towards identifying genes and gene products induced during low oxygen conditions. Promoter elements and transcription factors involved in the regulation of anaerobically induced genes have been characterized. In this paper an account is presented of the molecular strategies that have been used in an attempt to increase flooding tolerance of crop plants.

Adaptation, Physiological↗