Search PubMed⌕ Search

Biomedical subjects

A Crawford

Publications and source records attributed to A Crawford.

At least 55 records · Page 3Linked to original sources
PubMed1993

The paradox of MHC-DRB exon/intron evolution: alpha-helix and beta-sheet encoding regions diverge while hypervariable intronic simple repeats coevolve with beta-sheet codons.

Twenty-one different caprine and 13 ovine MHC-DRB exon 2 sequences were determined including part of the adjacent introns containing simple repetitive (gt)n(ga)m elements. The positions for highly polymorphic DRB amino acids vary slightly among ungulates and other mammals. From man and mouse to ungulates the basic (gt)n(ga)m structure is fixed in evolution for 7 x 10(7) years whereas ample variations exist in the tandem (gt)n and (ga)m dinucleotides and especially their "degenerated" derivatives. Phylogenetic trees for the alpha-helices and beta-pleated sheets of the ungulate DRB sequences suggest different evolutionary histories. In hoofed animals as well as in humans DRB beta-sheet encoding sequences and adjacent intronic repeats can be assembled into virtually identical groups suggesting coevolution of noncoding as well as coding DNA. In contrast alpha-helices and C-terminal parts of the first DRB domain evolve distinctly. In the absence of a defined mechanism causing specific, site-directed mutations, double-recombination or gene-conversion-like events would readily explain this fact. The role of the intronic simple (gt)n(ga)m repeat is discussed with respect to these genetic exchange mechanisms during evolution.

Alleles↗
PubMed1993

Ultrasound diagnosis of plantar fasciitis.

There is currently no objective reliable diagnostic test for plantar fasciitis inasmuch as diagnosis cannot be made on the basis of finding a heel spur on radiography (x-ray). In this single-blind observational study, ultrasonography was used to measure plantar fascia thickness in subjects with clinically suspected plantar fasciitis and in control subjects. It was concluded that the population mean plantar fascia thickness is greater for people with plantar fasciitis than for people without heel pain (P < .0005) and that the difference is clinically significant. The ultrasonic appearance of the plantar fascia in plantar fasciitis indicated inflammatory changes.

Adult↗
PubMed1991

Disability in persons hospitalized with AIDS.

This study documents the types and degree of disability seen in persons with AIDS at discharge from acute hospitalization. Based on 37 discharge evaluations using the Functional Independence Measure (FIM), 60% required human assistance in at least one of 18 FIM areas. Thirty-two percent required human assistance in five or more areas. Fifty-one and 38% required human assistance in stair climbing and ambulation, respectively. Feeding and bathing required assistance in about 33% and transferring to tub or shower in 25% of the sample. Increasing disability was associated with longer duration of AIDS diagnosis and increasing lengths of hospital stay (P less than 0.01 and P less than 0.05, respectively). There were individuals who remained nearly functionally independent up to 30 months after an AIDS defining event. The overall variability in function, however, was not significantly different between those with diagnoses less than and greater than 12 months. We conclude that significant physical disability exists in persons with AIDS at discharge from acute hospitalization. Consultation with and intervention by rehabilitation professionals may be helpful in the management of physical disability in this population and setting.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Translocations t(14;18) and t(8;14) with rearranged bcl-2 and c-myc in a case presenting as B-ALL (L3).

Follicular lymphoma is a low grade malignancy characterized by the translocation t(14;18), which involves the putative oncogene bcl-2. We describe a 73-year-old patient presenting with Burkitt acute lymphoblastic leukemia (B-ALL) L3 (Burkitt type), whose cells had the following immunophenotype: CD19+, CD22+, HLA-DR+, CD10+, TdT-, Cyt IgM-, CD34-. Analysis of 25 peripheral blood metaphases showed the presence of t(14;18) (q32;q21), and t(8;14) (q24;q32) in 24 cells and t(14;18) only in one cell, suggesting that the latter translocation came first during clonal evolution. Both bcl-2 and c-myc were rearranged in addition to the immunoglobulin heavy and light chain genes. The presence of small lymphoid cells in paratrabecular areas on the bone marrow biopsy, together with evidence of cytogenetic clonal evolution, was indicative of a transformation from a low grade follicular lymphoma to a more aggressive Burkitt type malignancy.

Aged↗
PubMed1989

Glutathione-dependent dechlorination of 1,6-dichloro-1,6-dideoxyfructose.

The metabolism of 14C- and 36Cl-labelled 1,6-dichloro-1,6-dideoxyfructose (DCF) was studied in the isolated perfused rat liver system. Dechlorination of DCF occurred in the liver and erythrocytes and was GSH-dependent. The GSH conjugate formed was identified by 13C and 1H n.m.r. as the 6-chlorofructos-1-yl-SG conjugate. It is proposed that the GS- anion attacks the low steady-state concentration of the reactive keto form of DCF and that the conjugate formed cyclizes to the dominant beta-anomer. 6-Chlorofructos-1-yl-SG conjugate of hepatic origin is excreted into bile, whereas that produced in erythrocytes does not enter the liver.

Animals↗
PubMed1989

Modulation of IL-1-induced collagenase production in articular chondrocytes by pertussis toxin.

The effects of pertussis and cholera toxins on interleukin-1 (IL-1) stimulated collagenase production from rabbit articular chondrocytes were investigated. Cholera toxin (50-1000 ng/ml) had no significant effect on IL-1-stimulated collagenase production. Pertussis toxin gave a 50-100% inhibition of collagenase activity induced by submaximal IL-1 concentrations. However, pertussis toxin had little effect on collagenase activity induced by maximal concentrations of IL-1. Optimal inhibitory effects were observed with 5-10 ng/ml of toxin.

Animals↗
PubMed1988

Self-reported alcohol consumption among population sub-groups in three areas of Britain.

Self-reported levels of alcohol consumption were recorded from residents of three areas in Britain with different official rates of drinking problems. Previous publications have shown minor area differences in the drinking habits of both sexes. The present analyses found no significant area differences for each sex in self-reported consumption among specific population subgroups.

Adult↗
PubMed1987

Passive smoking.

Explore the source record for details and available documents.

Humans↗
PubMed1987

Passive smoking.

Explore the source record for details and available documents.

Humans↗
PubMed1987

Interleukin 1 preferentially stimulates the production of tissue-type plasminogen activator by human articular chondrocytes.

Interleukin 1, derived from human placenta, stimulates plasminogen activator activity in human articular chondrocytes. The stimulation of plasminogen activator activity can be abolished by preincubation of placental interleukin 1 with an antiserum to homogeneous 22K factor, a species of interleukin 1 beta, indicating that the stimulation of plasminogen activator activity is due to interleukin 1 and not contaminating factors. Chondrocytes produce three species of plasminogen activator, with apparent Mr approximately 50,000, 65,000 and 100,000 as determined after sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis with gels containing casein and plasminogen. Both placental interleukin 1 and 22K factor enhance the production of the species of Mr approximately 65,000 and 100,000. Comparison of the mobility of the plasminogen activator species on SDS-polyacrylamide gel electrophoresis with human urokinase (u-PA) and human melanoma tissue-type plasminogen activator (t-PA) and studies with antibodies to these enzymes indicate that the Mr approximately 50,000 species is a u-PA and the Mr approximately 65,000 a t-PA. The Mr approximately 100,000 species is possibly an enzyme-inhibitor complex. Interleukin 1 therefore appears to enhance the production of t-PA and a putative enzyme-inhibitor complex. Abolition of plasminogen activator activity in the fibrin plate assay with antibodies to t-PA and u-PA also confirms enhanced t-PA production on interleukin 1 stimulation, though there is also evidence for increased cell-associated production of u-PA.

Cartilage, Articular↗
PubMed1987

Attitudes about alcohol: a general review.

This paper reviews 266 articles relating to attitudes towards alcohol use and misuse. It is concluded that adults typically regard themselves as moderate drinkers and disapprove of excessive drinking by others, expressed attitudes vary in accordance with respondent characteristics, drinker characteristics, beverage and amount, setting and time, the term 'alcoholism' has pejorative connotations, but there is no public consensus about etiology or treatment, and alcohol-related attitudes are generally poor predictors of behaviour (but need not be so). It is suggested that a pool of items relating to topic areas of continuing interest be created in order to increase comparability between surveys and further research using more complex attitudinal models be undertaken.

Alcohol Drinking↗
PubMed1987

Nuclear magnetic resonance spectroscopy reveals the metabolic origins of proline excreted by an Escherichia coli derivative during growth on [13C]acetate.

We have used 13C nuclear magnetic resonance to monitor acetate metabolism in a proline-overproducing strain of Escherichia coli growing on 13C-labeled acetate. The conversion of 13C-labeled acetate to proline by actively dividing cells was followed in vivo, and the site specificity of the incorporation of the acetate carbons in the proline was determined from spectra of butanol extracts of the growth media. The degree of incorporation of deuterium from partially deuterated water into various sites on the proline was monitored from the beta-deuterium-shifted signals in the 13C spectra. The spectra provide information on the origin of the carbons and the protons during proline biosynthesis.

Acetates↗
PubMed1987

Bias in a survey of drinking habits.

This paper presents data from a general population survey of three areas of Britain which manifest considerable differences in official rates of problem drinking, yet show similar patterns and levels of alcohol consumption. Consideration of various sources of bias (non-response, forgetting, selective under-reporting, and interviewer) suggest that they do not differentially influence self-reported alcohol consumption in the three areas.

Adult↗