PubMed Health⌕ Search

Biomedical subjects

D Birch

Publications and source records attributed to D Birch.

At least 37 records · Page 2Linked to original sources
PubMed1995

A prospective study of cortical scarring in acute febrile pyelonephritis in adults: clinical and bacteriological characteristics.

Previous reports have demonstrated lesions on computerized axial tomography (CT), and nuclear scintigraphy (DMSA) in acute pyelonephritis (PN). We undertook a prospective study of all patients presenting to our hospital with PN over 40 months. Patients who fulfilled diagnostic criteria, were treated with intravenous antibiotics. Excluding two who were pregnant, all patients had imaging by intravenous urography (IVU), CT and DMSA during their admission. Urine samples were collected prior to treatment. Patients without IVU evidence of cortical scarring but with parenchymal defects on CT and/or DMSA underwent a repeat DMSA three or more months after the acute episode. Of the 164 patients, 142 were female. E. coli was found in 116 patients. Forty-six patients had an abnormality on IVU. Of the 106 patients without IVU evidence of cortical scarring, 59 had a defect on CT and/or DMSA. Late DMSA scans in 35 of these 59 patients showed a persistent abnormality in 77%. E. coli characteristics such as P-fimbriae and Type 1 fimbriae were not predictive of acute imaging abnormalities. Inhibition of E. coli growth by the addition of EDTA was highly predictive of acute CT and DMSA abnormalities with a sensitivity of 83.3% and a specificity of 82.8%. Acute pyelonephritis is often associated with acute CT and/or DMSA abnormalities which may evolve into renal cortical scars. Acute scan abnormalities can be predicted by the presence of E. coli which were susceptible to EDTA in culture. Late scarring could not be predicted by clinical features, response to treatment or antibiotic used.

Acute Disease↗
PubMed1994

Influence of total colectomy on serum antineutrophil cytoplasmic antibodies in inflammatory bowel disease.

Perinuclear antineutrophil cytoplasmic antibodies (pANCAs) have previously been demonstrated in patients with various forms of vasculitis and more recently in those with inflammatory bowel disease (IBD) by an indirect immunofluorescence technique. Sera from 194 patients were tested for pANCAs: 101 with ulcerative colitis (43 with varying grades of disease severity, 19 after subtotal colectomy, 39 following restorative proctocolectomy), 40 with Crohn's disease, five with indeterminate colitis, 24 patients without IBD and 24 healthy volunteers (controls). The overall prevalence of pANCAs in patients with ulcerative colitis was 70.3 per cent (71 of 101). These antibodies were still present in 29 of 39 patients after restorative proctocolectomy, in whom the median follow-up after surgery was 2 years. All five patients who had pouchitis after restorative proctocolectomy were pANCA positive. By contrast, only ten of 40 patients with Crohn's disease had pANCAs, nine of whom had Crohn's colitis. No pANCAs were detected in controls. These results show that pANCAs are more prevalent in colonic IBD, especially ulcerative colitis. The persistence of pANCAs in the sera for 2 years after restorative proctocolectomy suggests that the antigens are not fully eradicated and, therefore, that it is not just the colon that is targeted immunologically in ulcerative colitis.

Adolescent↗
PubMed1994

Anticardiolipin wet workshop report. Fifth International Symposium on antiphospholipid antibodies.

An anticardiolipin wet workshop was conducted at the Fifth International Antiphospholipid Symposium (San Antonio, Texas, September 9-12, 1992). The workshop had four objectives: 1. to determine variability in measurement of immunoglobulin (Ig) G, IgM, and IgA anticardiolipin of eight unknown sera; 2. to examine the correlation between three commercial enzyme-linked immunosorbent assay (ELISA) kits and the Antiphospholipid Standardization Laboratory; 3. to examine protocols by which anticardiolipin binding to phospholipid antigens and beta 2 glycoprotein 1 (beta 2GP1) might be compared; and 4. to examine the beta 2GP1 effect on cardiolipin binding activity. Results showed good overall correlation of quantitative anticardiolipin measurements between workshop participants and the Antiphospholipid Standardization Laboratory. Correlation with individual ELISA kits was also good. With respect to the third objective, all participants showed comparable binding to cardiolipin and phosphatidylserine but none to phosphatidylcholine or beta 2GP1. Finally, beta 2GP1 enhanced, but was not essential for, anticardiolipin binding. This workshop will not settle controversies about anticardiolipin measurement and specificity, but suggests protocols to resolve these issues.

Antibodies, Anticardiolipin↗
PubMed1994

Chemical preservation of urine sediment for phase-contrast microscopic examination.

A major difficulty in diagnostic urinary microscopy is the need to observe a freshly passed urine specimen. This study illustrates the use of glutaraldehyde (GA) and formaldehyde (FA) to preserve urinary sediment for diagnostic microscopy. GA and FA in whole urine cause a precipitate to form if there is a trace or more of proteinuria. This can be eliminated by centrifugation and fixation of urine sediment. Red blood cells (RBC) and casts are adequately preserved for diagnostic microscopy for at least 3 months. However, subtle changes in RBC morphology consisting of hexagonal distortion and wrinkling of cell margins are seen in some cells. White blood cells (WBC) are less reliably preserved. Diagnostic phase-contrast microscopy can be performed on urine sediment stored at room temperature for up to 3 months after fixation with GA or FA.

Cell Count↗
PubMed1994

An audit of the quality of operation notes in two district general hospitals. Are we following Royal College guidelines?

The quality of medical record keeping is being subjected to increasingly close scrutiny. The 1992 report of the National Confidential Enquiry into Perioperative Deaths (NCEPOD) noted a considerable variation in the quality of operation notes submitted by all contributing surgical specialties. This study has audited the quality of 264 general surgical operation notes written by 10 consultants and 16 trainees in two district general hospitals (DGH). Postoperative instructions were absent in nearly two-thirds of operation notes and serial numbers of prostheses were rarely recorded. On almost every criterion trainees scored higher than consultants and emergency operation notes scored better than elective notes. About 70 per cent of notes written by consultants were illegible or the procedure could not be understood from the description given, by the nurse or junior doctor collecting the data. Until word processor databases become more widespread in operating theatres, it is suggested that a specifically designed proforma be used, with prescribed headings to act as aides-mémoire for the surgeon.

Documentation↗
PubMed1992

Visual and brain function measurements in studies of n-3 fatty acid requirements of infants.

Dietary n-6 or n-3 fatty acid deficiencies result in changes in brain and retinal phospholipid composition that can affect cell membrane and organ function. An n-3 fatty acid deficiency has been associated with altered electroretinograms and reduced visual acuity in animals. Other promising methods for assessing the effects of fatty acid deficiencies on brain and retinal maturation include visual-evoked potential acuity, sleep-wake cycle, auditory brain stem-evoked response, somatosensory-evoked potential measurements, and the Fagan and forced-choice preferential looking acuity tests. Preterm infants fed a formula low in alpha-linolenic acid (18:3n-3) had significant electroretinographic changes at discharge from the nursery, indicating a delay in rod photoreceptor maturation. However, infants fed human milk or supplementary n-3 fatty acids as marine oil had electroretinogram indexes like those of infants of comparable age tested soon after birth. Visual cortex function, measured by pattern reversal visual-evoked potential and forced-choice preferential looking visual acuity response, was also better in infants fed human milk or marine oil-supplemented formula than in infants fed formulas without docosahexaenoic acid (22:6n-3). Studies of term infants suggest that visual acuity is more mature in breast-fed than in formula-fed infants [corrected] at 4 months and 3 years of age.

Brain↗
PubMed1989

Chromosomal localization of murine interleukin-1 alpha and beta genes.

DNA analyses of mouse X Chinese hamster somatic cell hybrids and of recombinant inbred mouse strains have previously shown that the interleukin-1 alpha and beta genes are tightly linked on murine chromosome 2, approximately 4.7 cM distal to beta-2-microglobulin. In this study, using in situ chromosome hybridization, we show that the two interleukin-1 genes are located in the F region of murine chromosome 2 and discuss this physical map position in relation to conserved genetic linkage groups.

Animals↗
PubMed1987

Nonisotopic M13 probes for detecting the beta-globin gene: application to diagnosis of sickle cell anemia.

M13 DNA probes labeled with biotinylated psoralen and a streptavidin-horseradish peroxidase conjugate provide nonradioactive detection of the sickle cell and normal alleles of the beta-globin locus. The two biotinylated probes contain single-stranded sequences complementary to two different Sau3AI restriction fragments from the 5' region of the beta-globin gene and double-stranded M13 vector sequences. These probes are labeled with biotinylated psoralen photochemically linked to DNA. After hybridization, the presence of biotinylated probe bound to target DNA is detected in 3 h by using a streptavidin-horseradish peroxidase conjugate and the substrate, 3,3',5,5'-tetramethylbenzidine. Digestion of the normal (beta A) allele of the beta-globin gene with MstII (or isoschizomers) yields a 1.14-kb restriction fragment, while digestion of the mutant beta S allele yields a 1.34-kb fragment. These fragments can be resolved by gel electrophoresis and detected by Southern blot hybridization. The nonradioisotopic probe system can detect the beta-globin restriction fragment in as little as 0.5 microgram of human DNA and can distinguish heterozygotes (beta A beta S) from homozygotes (beta A beta A or beta S beta S) in 2.0 micrograms of human DNA.

Alleles↗
PubMed1986

Pneumonia associated with infection with pneumocystis, respiratory syncytial virus, chlamydia, mycoplasma, and cytomegalovirus in children in Papua New Guinea.

Paired serum samples were collected from 94 children with pneumonia admitted to Goroka Hospital, Papua New Guinea. All but three of the children were aged 1-24 months. Only nine children were malnourished, with weight for age less than 70% of the Harvard median (three had weight for age less than 60% of the Harvard median). Pneumocystis carinii antigen was detected in the serum of 23 children. Twenty two children had serological evidence of recent infection with respiratory syncytial virus. Five children were probably infected with Chlamydia trachomatis at the time of the study, and there was less convincing serological evidence of current infection in a further 11 children. Five children showed a fourfold rise in antibody to Mycoplasma pneumoniae. Although only one child showed a fourfold rise in antibody to cytomegalovirus, 86 children had this antibody. No child showed a fourfold rise in antibody to Ureaplasma urealyticum or Legionella pneumophila. P carinii, respiratory syncytial virus, C trachomatis, M pneumoniae, and cytomegalovirus may be important causes of pneumonia in children in developing countries.

Child, Preschool↗
PubMed1986

Possible immunoenhancement of persistent viremia by feline leukemia virus envelope glycoprotein vaccines in challenge-exposure situations where whole inactivated virus vaccines were protective.

Kittens immunized with purified native FeLV-gp70 or -gp85 envelope proteins developed ELISA, but not virus neutralizing, antibodies in their serum to both whole FeLV and FeLV-gp70. Kittens vaccinated with envelope proteins and infected with feline sarcoma virus (FeSV) developed smaller tumors than nonvaccinates, but a greater incidence of persistent retroviremia. Similarly, FeLV-gp70 and -gp85 vaccinated kittens were more apt to become persistently retroviremic following virulent FeLV challenge exposure than nonvaccinates. Kittens vaccinated with inactivated whole FeLV developed smaller tumors after FeSV inoculation and had a lower incidence of persistent retroviremia than nonvaccinates. The protective effect of inactivated whole FeLV vaccine against persistent retroviremia was also seen with FeLV challenge-exposed cats. Protection afforded by inactivated whole FeLV vaccine was not associated with virus neutralizing antibodies, although ELISA antibodies to both whole FeLV and FeLV-gp70 were induced by vaccination.

Animals↗
PubMed1977

Effects of constant illumination on vision in the albino rat.

The characteristics of photically-induced blinding in the albino rat were investigated with physiological (the electroretinogram--ERG) and behavioral (luminance discrimination) techniques. These indices were obtained both before and during exposure to constant illumination (2600 lux). In trast to previous results, the findings of this study indicate that both the amplitude of the ERG and the ability to discriminate test lights decline rapidly and at approximately the same rate following the onset of constant illumination. These results, in conjunction with others already in the literature, lead to the suggestion that the degree of correspondence between behavioral and other measures of photically-induced blinding is dependent on the rate of retinal degeneration.

Albinism↗