Reliability testing of a sun exposure questionnaire for the Northern Ireland population

BACKGROUND: Sunbathing and other types of exposure to ultraviolet radiation are the major preventable risk factors for skin cancer. Due to the continued increase in incidence of melanoma in Northern Ireland, we have conducted a questionnaire survey in an attempt to gather information about sunbathing habits and other forms of ultraviolet light exposure amongst the Northern Ireland population. AIM: The aim of this study was to examine the test-retest reliability of a questionnaire used in a large-scale cross-sectional population survey pertaining to sunbathing habits, use of sun screen, skin types, and frequencies of sunburn and to assess the responses given by the subjects to determine the nature of their sun-related behaviour. METHODS: Thirty control subjects were randomly selected from a population control sample participating in a large case-control study investigating melanoma in the Northern Ireland population. All participants completed the interview questionnaire on two occasions, with a median of 15 days (range, 12-42 days) between interviews. We randomly chose control subjects who had been visited by the same research nurse, thus ruling out interobserver bias in the analyses. We used the test-retest method. Kappa statistics were used to calculate the association between test and retest scores of all the individual items. If the items contained within the questionnaire are reliable, then repeated measurement after a fairly short period of time should result in high within-subject repeatability. RESULTS: Questions pertaining to hours spent in the sun and sun bed usage showed high reliability (kappa > 0.7). Questions about sunscreen usage showed moderately high reliability (kappa > 0.6) in all but one of the 10-year age bands and complete agreement (kappa = 1) in one age category (>50 years). CONCLUSION: This questionnaire is a reliable method of assessing sun-associated behaviour identifying high-risk sun-related behaviour and misconceptions about tanning, which can be targeted for improvement in public health.     

Progenitor cell assays predict hematopoietic reconstitution after syngeneic transplantation in mice

Hematopoietic reconstitution following syngeneic bone marrow transplantation with graded doses of untreated and drug-treated bone marrow was studied in B6D2F1 mice. Granulocyte-macrophage colony- forming units (CFU-GM) and spleen colony-forming units (CFU-S) showed similar in vitro drug sensitivities. Both the speed of hematologic recovery and survival of mice transplanted with untreated or drug- treated bone marrow were directly related to the number of CFU-GM or CFU-S transplanted. Similar hematologic recovery was seen for untreated marrow transplants and treated transplants that had similar CFU-GM or CFU-S content. There is a minimum number of transplanted CFU-GM or CFU- S that allows survival of lethally irradiated mice. This number is present in a marrow transplant containing the equivalent of 5 X 10(3) untreated cells or producing one to two spleen colonies. There also exists a maximum value for the number of hematopoietic progenitors in a marrow graft, above which the rate of hematologic recovery following transplantation is rapid and no detectable increase in the rate is seen with increasing CFU-GM or CFU-S content. The presence of this maximum value for transplanted progenitors and variations in culture techniques are probably the reasons previous studies have not always shown a correlation between CFU-GM content and hematologic recovery after bone marrow transplantation.     

Characterization of murine CD34, a marker for hematopoietic progenitor and stem cells

CD34 is expressed on human hematopoietic stem and progenitor cells, and its clinical usefulness for the purification of stem cells has been well established. However, a similar pattern of expression for murine CD34 (mCD34) has not yet been determined. Two polyclonal anti-mCD34 antibodies that specifically recognize both endogenous and recombinant murine CD34 were developed to characterize the mCD34 protein and to determine its pattern of expression on murine cell lines and hematopoietic progenitor cells. Fluorescence-activated cell sorter analysis showed that mCD34 is expressed on NIH/3T3 embryonic fibroblasts, PA6 stromal cells, embryonic stem cells, M1 leukemia cells, and a subpopulation of normal bone marrow cells. Murine CD34 was found to be a glycoprotein expressed on the cell surface as either a full-length (approximately 100 kD) or truncated (approximately 90 kD) protein in NIH/3T3 and PA6 cells. Recombinant full-length CD34, when expressed in the CHO-K1 cell line, had a molecular weight of approximately 105 kD. Full-length CD34 expressed on M1 leukemia cells, had a higher apparent molecular weight (110 kD). These results suggest that there are glycosylation differences between CD34 expressed by different cell types. The full-length form, but not the truncated form, is a phosphoprotein that is hyperphosphorylated in response to 12-0- Tetradecanoyl phorbol 13-acetate treatment, suggesting potential functional differences between the two forms. Selection of the 3% highest-expressing CD34+ bone marrow cells enriched for the hematopoietic precursors that form colony-forming unit-spleen (CFU-S), CFU-granulocyte-macrophage, and burst-forming unit-erythroid. Transplantation of lethally irradiated mice with these cells demonstrated both short- and long-term repopulating ability, indicating that this population contains both functional hematopoietic progenitors and the putative stem cell. These antibodies should be useful to select for murine hematopoietic stem cells.     

NMR analysis of a potent decapeptide agonist of human C5a anaphylatoxin

A NMR investigation in H₂0, TFE and DMSO of a conformationally constrained, potent decapeptide agonist of human C5a, YSFKDMPLaR (C5a₆₅-₇₄, Y65, F67, P71, d -Ala73) showed that its N-terminal region (YSFKD) exhibited an extended backbone conformation in H₂O and a more twisted conformation in both TFE/H₂O (30:70, v/v; referred to as TFE) and DMSO. The C-terminal region (MPLaR) of the peptide adopted compact, turn-like structures. In H₂O, the C-terminal region adopted a type II β-turn or a distorted type V/II β-turn involving residues PLaR. In the distorted type V/II β-turn, Leu72 exhibited a conformation typical of a type V β-turn, whereas D -Ala73 exhibited a conformation typical of a type II β-turn. The distorted type V/II β-turn overlapped with an inverse γ-turn involving residues MPL. In DMSO, the C-terminal region had the analogous inverse y-turn and the V/II γ-turn found in H₂O. In many of the DMSO structures, two inverse γ-turns in the MPL and PLa positions formed a double-inverse γ-turn. None of the turns observed in H₂O were present in TFE. However, in TFE, the PLa residues formed an inverse γ-turn. Overall, the turn-like structural motifs in the C-terminal region of the peptide in both H₂O and DMSO (but not in TFE) agreed with the biologically important conformations obtained earlier by the structure-function analysis of a panel of C5a agonist peptides. These motifs may represent key structural elements important for C5a agonist activity and may be used to design the next generation of C5a agonist and antagonist analogues. © Munksgaard 1998.     

Differences in prevalence of self-reported musculoskeletal symptoms among computer and non-computer users in a Nigerian population: a cross-sectional study

Background  

Literature abounds on the prevalent nature of Self Reported Musculoskeletal Symptoms (SRMS) among computer users, but studies that actually compared this with non computer users are meagre thereby reducing the strength of the evidence. This study compared the prevalence of SRMS between computer and non computer users and assessed the risk factors associated with SRMS.     

Anti-Inflammatory Effect of Bioflora Probiotic Administered Orally or Subcutaneously with Live or Dead Bacteria

The anti-inflammatory effect of Bioflora probiotic administered orally or subcutaneously with viable or nonviable bacteria was analyzed in two experimental models of randomly selected female Wistar rats. The use of indomethacin at a dose of 50 mg/kg was associated with gastric necrotic lesions and multiple erosions of the small intestine, with marked mucosal neutrophil infiltrate measured by myeloperoxidase (MPO). Probiotics prevented both gastrointestinal lesions and neutrophil infiltrate (p < 0.001). In the model of carrageenin-induced plantar edema in the rat, the oral or subcutaneous administration of Bioflora with live or dead bacteria proved to prevent plantar edema (p < 0.001). We concluded that Bioflora probiotic given orally or subcutaneously with live or dead bacteria has an anti-inflammatory effect.