Search PubMed⌕ Search

Biomedical subjects

J McDougall

Publications and source records attributed to J McDougall.

At least 19 recordsLinked to original sources

Report of an uncommon cluster of septic arthritis of the hip in premature newborns: three cases in a period of 3 months.

We report an uncommon cluster of this rare condition which occurred within a very short period of time in our unit. We reviewed the current literature and observed that the diagnosis is often delayed, which can have very serious consequences for the outcome. Our 3 patients have had an uncomplicated course so far and follow-up examination at almost one year was normal. A high index of suspicion for the diagnosis and early and aggressive treatment is necessary.

Amikacin↗

Oil contamination of sedimentary shores of the Galápagos Islands following the wreck of the Jessica.

Sediment samples were collected from sandy beaches at a variety of sites in the southern Galápagos Archipelago to assess levels of hydrocarbon contamination following the wreck of the oil tanker Jessica. Hydrocarbon levels in sediments were generally very low by international standards ranging between 0.4 and 48.9 ppm, with contamination attributable to the Jessica only detected at three sites Santa Fe, Playa Estación (Puerto Ayora, Santa Cruz) and Long Beach (Isabela). There was evidence of residual hydrocarbon contamination from sources other than the wreck of the Jessica.

Accidents↗

A prospective study of the short-term outcomes of hysterectomy with and without oophorectomy.

OBJECTIVE: To determine the symptom profile and satisfaction rate for women undergoing hysterectomy with and without oophorectomy STUDY DESIGN: Women under 46 years of age who underwent hysterectomy with (n = 266) and without oophorectomy (n = 57) were followed for six months. RESULTS: Satisfaction was high at six months. In-hospital complication rates were 28% in Group 1 and 39% in Group 2 (p = 0.11). Pelvic pain was reported in more than half the women at six weeks. A reduction in constipation, diarrhoea, abdominal and pelvic pain, and depression was reported at six months. Quality of sexual function in women did not improve. New symptoms of pelvic pain or depression were present at six months in more than 16% to 37% of the women. Regrets about loss of fertility were increased at six months. CONCLUSIONS: Although levels of satisfaction with the procedure of hysterectomy were high, new symptoms and regrets about the loss of fertility were commonly reported.

Adaptation, Physiological↗

Increased ACTH levels do not alter renal 11beta-hydroxysteroid dehydrogenase type 2 gene expression in the sheep.

The regulation of renal 11beta-hydroxysteroid dehydrogenase type 2 (11betaHSD2) gene expression is poorly understood. Inhibition of expression can result in hypertension. An example of this is in ectopic adrenocorticotropin (ACTH) syndrome (EAS). Inhibition of 11betaHSD2 activity is suggested by the observed increased ratio of cortisol to cortisone in both plasma and urine. To investigate whether ACTH or ACTH-dependent steroids can modulate renal 11betaHSD2 gene expression we analysed renal 11betaHSD2 mRNA levels after treatment with ACTH of 1 H and 24 H and demonstrated no change in the levels of gene expression. We have demonstrated in this study that the expression of 11betaHSD2 in the kidney is unaltered by ACTH. The reduced inactivation of cortisol by 11betaHSD2 observed in EAS is likely to be in part due to end product inhibition or substrate overload of the enzyme by endogenous substrates (cortisol, corticosterone, etc) rather than inhibition of 11betaHSD2 at the transcriptional level by either ACTH or ACTH regulated steroids.

11-beta-Hydroxysteroid Dehydrogenase Type 2↗

A randomized comparison of intradermal and intramuscular vaccination against hepatitis B virus in incident chronic hemodialysis patients.

Hepatitis B virus (HBV) remains a threat to hemodialysis patients. Nevertheless, the vaccination rate against this virus is low, perhaps because of the low conversion rate. Although intradermal (ID) vaccination has been proven to be effective (even in patients nonresponsive to intramuscular [IM] vaccination), the duration of immunity was short. The impact of vaccination route and a greater peak antibody (Ab) titer on conversion rate and duration of immunity after ID or IM vaccination was compared in incident hemodialysis patients. Forty-nine patients were randomly assigned to treatment with 5 microgram of recombinant hepatitis B vaccine (Engerix B; Smith Kline Beecham Pharma Inc, Oakville, ON, Canada) ID every 2 weeks up to either a peak Ab titer of 1,000 IU/L or greater or 52 doses, whereas 48 patients were administered 40 microgram IM at 0, 1, 2, and 6 months. Group demographics were similar. Conversion was achieved in 97.6% of the ID group and 90.5% of the IM group (P: = 0.16). There was no difference between ID and IM groups in time required to convert, peak Ab titer reached, and proportion of patients with a peak Ab titer of 1,000 IU/L or greater. Overall, the duration of immunity was not different after ID or IM vaccination (P = 0.683), and patients in the IM group with a peak Ab titer of 1,000 IU/L or greater had a longer duration of immunity (P = 0.001). In conclusion, a high conversion rate and long duration of immunity against HBV can be achieved cost-effectively in the end-stage renal disease population using the ID or IM route and aiming for an Ab titer exceeding 1,000 IU/L. Based on these data, we provide recommendations for vaccination and surveillance in this population.

Female↗

Does aspirin have a role in improving pregnancy outcome for women with the antiphospholipid syndrome? A randomized controlled trial.

OBJECTIVE: This pilot investigation was undertaken to assess the efficacy of low-dose aspirin therapy for the treatment of women with antiphospholipid antibodies when recurrent miscarriage is the only sequela. STUDY DESIGN: A double-blind, randomized, placebo-controlled trial was conducted in the setting of the recurrent miscarriage clinic of a tertiary referral obstetric hospital. The participants were 50 women with a history of recurrent miscarriages (>/=3) and antiphospholipid antibodies. Women with systemic lupus erythematosus or a history of thrombosis were excluded. Women were recruited after full investigative screening at the recurrent miscarriage clinic. Women with >/=3 fetal losses and persistently positive results for antiphospholipid antibodies were randomly allocated to receive either aspirin (75 mg daily) or placebo. Investigators, clinicians, and patients were blinded to the treatment. Rates of live births, antenatal complications, and delivery and neonatal outcomes were recorded prospectively. Data were compared by chi(2) analysis with Yates' correction, the Fisher exact test, or the Student t test as appropriate. RESULTS: There were 10 exclusions after random assignment because of inappropriate inclusion. Eighty-five percent of the placebo (17/20) group and 80% of the aspirin-treated group (16/20) were delivered of live infants. This difference was not significant. There were no significant differences in antenatal complications or neonatal morbidity between the groups. CONCLUSIONS: This preliminary study suggests that low-dose aspirin has no additional benefit when added to supportive care for women for whom recurrent early fetal loss is the only sequela of the antiphospholipid syndrome. This live birth rate with supportive care alone exceeds the published live birth rates for women with antiphospholipid antibody-mediated recurrent fetal loss who were treated with heparin or corticosteroids. This trial, like all other trials in this field, is small, but its results bring into question the need for pharmacologic intervention for women with antiphospholipid syndrome for whom recurrent fetal loss is the only sequela. Our results highlight the need for a large randomized controlled trial to identify the optimal treatment for this group of women and justify the inclusion of a placebo arm in any such trial.

Adult↗

Theatres of the psyche.

Fragments of the analytic voyage of a forty year old patient, haunted by the idea of her death since infancy when confronted with the anguish that accompanies the discovery of a potentially death dealing illness. In three years of intensive analytic work, her way of functioning psychically changed dramatically (her flight from imaginative life, total disaffectation of her emotional life, psychic deafness regarding her body and its messages...). These discoveries led to my analysand's resuming her psychoanalytic voyage in these words: 'Even if I am destined to die of this cancer, at least I shall have lived'.

Adult↗

Orphanin FQ is the major OFQ1-17-containing peptide produced in the rodent and monkey hypothalamus.

In order to investigate the processing of OFQ containing peptides in the hypothalamus we have developed a sensitive and quantitative radioimmunoassay for OFQ. We fractionated rodent and monkey hypothalamic extracts by reversed-phase high performance liquid chromatography and found that the extracts contained multiple peaks of OFQ immunoreactivity with the major peak co-eluting with synthetic OFQ1-17. Mouse hypothalamic extracts were also fractionated by SDS-PAGE to determine the apparent molecular weights of molecules containing the OFQ peptide. Multiple peaks of OFQ immunoreactivity, ranging in size from approximately 1 to 30 kilodaltons, were detected by this method. These results suggest that OFQ1-17 is processed to smaller peptides in mouse and monkey hypothalamic neurons.

Amino Acid Sequence↗

Telomerase activation in cervical cancer.

It has been hypothesized that infection with high-risk human papillomaviruses (HPVs), in conjunction with other cellular events, plays a critical role in the development of cervical cancer. Activation of telomerase, a ribonucleoprotein enzyme complex that synthesizes telomere repeats, has been associated with acquisition of the immortal phenotype in vitro and is commonly observed in human cancers. In this study, we have examined 10 high-grade cervical cancers for telomerase activity and for the presence of HPV. Telomerase activity was detected in all of the cancers but in none of the paired histopathologically normal uterine tissues or in normal cervical epithelium. Analysis of these same tissues for HPV nucleic acids by polymerase chain reaction (PCR) using primers from the HPV L1 and E6 open reading frames demonstrated that 7 of 10 cancers were positive for HPV, 3 for HPV type 16 (HPV-16), and 4 for HPV-18. In one case, HPV-16 was detected in histopathologically normal uterine tissue, the same type as that detected in the cancer from the same patient. HPV DNA was not detected in 3 of 10 cancers. These results indicate that telomerase activation is common in high-grade cervical cancers and suggests that telomerase activity may be a useful diagnostic marker for the disease.

Adenocarcinoma↗

The complex bet promoters of Escherichia coli: regulation by oxygen (ArcA), choline (BetI), and osmotic stress.

The bet regulon allows Escherichia coli to synthesize the osmoprotectant glycine betaine from choline. It comprises a regulatory gene, betI, and three structural genes: betT (choline porter), betA (choline dehydrogenase), and betB (betaine aldehyde dehydrogenase). The bet genes are regulated by oxygen, choline, and osmotic stress. Primer extension analysis identified two partially overlapping promoters which were responsible for the divergent expression of the betT and betIBA transcripts. The transcripts were initiated 61 bp apart. Regulation of the promoters was investigated by using cat (chloramphenicol acetyltransferase) and lacZ (beta-galactosidase) operon fusions. Mutation of betI on plasmid F'2 revealed that BetI is a repressor which regulates both promoters simultaneously in response to the inducer choline. Both promoters remained inducible by osmotic stress in a betI mutant background. On the basis of experiments with hns and hns rpoS mutants, we conclude that osmoregulation of the bet promoters was hns independent. The bet promoters were repressed by ArcA under anaerobic growth conditions. An 89-bp promoter fragment, as well as all larger fragments tested, which included both transcriptional start points, displayed osmotic induction and BetI-dependent choline regulation when linked with a cat reporter gene on plasmid pKK232-8. Flanking DNA, presumably on the betT side of the promoter region, appeared to be needed for ArcA-dependent regulation of both promoters.

Bacterial Outer Membrane Proteins↗

Rapid reduction of serum cholesterol and blood pressure by a twelve-day, very low fat, strictly vegetarian diet.

OBJECTIVE: This study was conducted to demonstrate the effectiveness of a strictly vegetarian, very low-fat diet on cardiac risk factor modification. METHODS: Five hundred men and women, participants in an intensive 12-day live-in program, were studied. The program focused on dietary modification, moderate exercise, and stress management at a hospital-based health-center. RESULTS: During this short time period, cardiac risk factors improved: there was an average reduction of total serum cholesterol of 11% (p < 0.001), of blood pressure of 6% (p < 0.001) and a weight loss of 2.5 kg for men and 1 kg for women. Serum triglycerides did not increase except for two subgroups: females age > or = 65 years with serum cholesterol < 6.5 mmol/L and for females 50 to 64 years with baseline serum cholesterol between 5.2-6.5 mmol/L. High-density lipoprotein cholesterol measured on 66 subjects decreased by 19%. CONCLUSION: A strict, very low-fat vegetarian diet free from all animal products combined with lifestyle changes that include exercise and weight loss is an effective way to lower serum cholesterol and blood pressure.

Aged↗

Analysis of the otsBA operon for osmoregulatory trehalose synthesis in Escherichia coli and homology of the OtsA and OtsB proteins to the yeast trehalose-6-phosphate synthase/phosphatase complex.

The Escherichia coli otsBA operon, located at min 42, was sequenced and shown to encode a 29.1-kDa trehalose-6-phosphate phosphatase (OtsB) and a 53.6-kDa trehalose-6-phosphate synthase (OtsA). Both proteins display sequence homology with subunits of the Saccharomyces cerevisiae trehalose-6-phosphate synthase/phosphatase complex, which is made up of the subunits TPS1, TPS2 and TPS3 (TSL1). OtsA has homology to the full-length TPS1, the N-terminal part of TPS2 and an internal region of TPS3 (TSL1). OtsB has homology to the C-terminal part of TPS2, but no homology to the other subunits. Primer extension analysis showed only one transcription start point upstream from otsB and one upstream from otsA, regardless of the growth conditions tested. The start codons of the otsB and otsA genes were established by N-terminal sequence determination of the proteins. The 3' end of the otsB coding region overlaps the 5' end of the otsA coding region by 23 nucleotides. The araH gene is located directly upstream from otsBA, and otsB may be identical to pexA.

Amino Acid Sequence↗

Comparative analysis of the protein components from 5S rRNA.protein complexes of halophilic archaebacteria.

The 5S RNA.protein complexes have been isolated from the 50S subunit of the halophilic archaebacteria Halobacterium cutirubrum, Halobacterium halobium, Halobacterium salinarium, Haloferax mediterranei, Haloferax volcanii and Haloarcula marismortui. The 50S subunits from most of the halophiles released a multiprotein ribonucleoprotein particle similar to that previously observed with the H. cutirubrum 5S RNA.protein complex, which contained proteins from the L5 and L18 ribosomal protein families. Ribosomes from H. marismortui, however, released an RNA.protein complex containing a single protein (L18) that is homologous to the single protein found in the eukaryotic 5S ribonucleoprotein complexes. N-terminal sequence analyses of the halophilic 5S RNA-binding proteins suggest that the L18 protein primary structure is highly conserved, with only the H. marismortui protein having a sequence difference in at least the first twenty amino acids. Although the L5 group of ribosomal proteins also shows a high conservation, it appears that the proteins may have had more freedom to diverge throughout evolution.

Amino Acid Sequence↗

A yeast gene for trehalose-6-phosphate synthase and its complementation of an Escherichia coli otsA mutant.

A Saccharomyces cerevisiae gene for trehalose-6-phosphate synthase (TPS1) was sequenced. The gene appeared to code for a protein of 495 amino acid residues, giving the protein a molecular mass of 56 kDa. The TPS1 gene was able to restore both osmotolerance and trehalose accumulation during salt stress in an Escherichia coli strain mutated in the otsA gene encoding trehalose-6-phosphate synthase. Complementation studies with E. coli galU mutants showed that the TPS1-encoded trehalose-6-phosphate synthase is UDP-glucose-dependent. Sequence analysis and data base searches showed that TPS1 is allelic to GGS1, byp1, cif1 and fdp1. A possible gene for trehalose-6-phosphate synthase in Methanobacterium thermoautotrophicum was identified.

Amino Acid Sequence↗

Dual infection with human papillomavirus in a population with overt genital condylomas.

BACKGROUND: Multiple human papillomavirus (HPV) genotypes have been demonstrated in individual patients; usually, different genotypes occur in different anatomic sites. OBJECTIVE: Our purpose was to evaluate the prevalence of multiple HPV types from the same anatomic site. METHODS: During the course of a study evaluating topical versus ablative therapy for external genital HPV, sequential biopsies on patients with external genital warts were performed. HPV DNA content was determined by Southern hybridization. Ninety-two specimens from 63 patients (48 women, 15 men) with genital warts were evaluated. RESULTS: Dual infection with two HPV genotypes was documented in each of four specimens (6.3%). Sequential biopsy specimens from the same anatomic site in the same person revealed dual infection in 5 of 12 sampled patients (41%). Overall, 14% of patients had dual genitourinary HPV infection. CONCLUSION: Counseling and follow-up of long-term complications, such as transmission and the risk of subsequent genitourinary carcinoma, should be performed on all patients with HPV because of the possibility of undetected HPV DNA types in the individual patient.

Adult↗

DNA sequence and analysis of the bet genes encoding the osmoregulatory choline-glycine betaine pathway of Escherichia coli.

The sequence was determined of 6493 nucleotides encompassing the bet genes of Escherichia coli which encode the osmoregulatory choline-glycine betaine pathway. Four open reading frames were identified: betA encoding choline dehydrogenase, a flavoprotein of 61.9kDa; betB encoding betaine aldehyde dehydrogenase (52.8kDa); betT encoding a proton-motive-force-driven, high-affinity transport system for choline (75.8kDa); and betl, capable of encoding a protein of 21.8kDa, implicated as a repressor involved in choline regulation of the bet genes. Identification of the genes was supported by subcloning, physical mapping of lambda placMu53 insertions, amino acid sequence similarity, or N-terminal amino acid sequencing. The bet genes are tightly spaced, with betT located upstream of, and transcribed divergently to, the tandemly linked betIBA genes.

Alcohol Oxidoreductases↗