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Biomedical subjects

M Smith

Publications and source records attributed to M Smith.

At least 217 records · Page 12Linked to original sources

The development of a continuous quality control programme for strict sperm morphology among sub-Saharan African laboratories.

Inter-technician and between-laboratory differences, especially during the evaluation of sperm morphology, have been a major cause of concern. The study aimed to develop an intensive training programme with intervals of continuous quality control assessments for sperm morphology. Twenty andrology laboratories from sub-Saharan Africa were invited to participate in a World Health Organization Special Programme of Research, Development and Research Training in Human Reproduction semenology workshop. Following intensive training in strict sperm morphololgy evaluation, a continuous quality control programme was introduced on a quarterly basis. At baseline, the mean (+/- SD) percentage difference reported between the participants and the reference laboratory reading was 33.50 +/- 11%. After training, the mean percentage difference had decreased to 14.32 +/- 5% at 3 months and to 5.00 +/- 5% at 6 months. Pairwise comparison of the differences at each evaluation time revealed the following: Baseline differences (pre-training) differed significantly from the differences at 3 months (P = 0.0002) as well as at 6 months after training (P = 0.007). The differences at 6 months did not differ significantly from those at 3 months (P = 0.27). Training of andrology technicians as well as continuous proficiency testing can be conducted on a national and international level with the support of a referring laboratory. Global quality control measurements in andrology laboratories should become mandatory, since these results indicate that continuous quality control for laboratory technicians can be highly successful.

Africa, Northern↗

The transactivation-competent carboxyl-terminal domain of AF-9 is expressed within a sexually dimorphic transcript in rat pituitary.

We have investigated the biological role of the cellular counterpart of the leukemogenic AF-9 gene by cloning the rat AF-9 (rAF-9) cDNA and defining the regulation of an anterior pituitary-specific rAF-9 transcript that is expressed in a sexually dimorphic manner. Expression of this transcript is down-regulated after puberty in females and can be subsequently up-regulated in adults by ovariectomy. Hormone replacement studies have provided direct evidence that rAF-9 mRNA expression is suppressed by estrogen. Mapping the 1.9 kb anterior pituitary transcript has shown that it corresponds in size to the rAF-9 cDNA clone, which contains an open reading frame (ORF) that is truncated compared with the human AF-9 ORF, but encodes a previously defined transcriptional activation domain. Thus, the cellular AF-9 gene is alternatively expressed in a manner that reflects the presence of translocated, functionally active (oncogenic) AF-9 sequences in leukemias. Using a novel antisera raised against a rAF-9 peptide, we have also demonstrated tissue- and sex-specific expression of a nuclear 41 kDa anterior pituitary protein and have localized this protein to a major population of growth hormone synthesizing cells. By localizing the expression and defining the physiological regulation of rAF-9, our studies have provided novel insights into the AF-9 gene that will facilitate an understanding of both oncogenic and endocrine roles.

Alternative Splicing↗

Changes in cerebral blood volume with changes in position in awake and anesthetized subjects.

UNLABELLED: Changes in posture affect cerebral blood volume (CBV), and moderate head-up tilt is used as a therapeutic maneuver to reduce CBV and intracranial pressure. However, CBV is rarely measured in the clinical setting. Near-infrared spectroscopy allows real-time bedside monitoring of cerebral hemodynamics, and we have used this technique to measure changes in CBV with changes in posture in 10 normal subjects and 10 propofol-anesthetized patients. In the awake subjects, changes in CBV were correlated with the degree of table tilt. CBV decreased with 18 degrees head-up tilt and increased with 18 degrees head-down tilt (P < 0.0001, r = -0.924). In anesthetized patients, there were differences between head-up and head-down tilt. In the head-down position, CBV was also correlated with the degree of table tilt (P < 0.001, r = -0.782), whereas there was a clinically insignificant reduction in CBV in the head-up position. Near-infrared spectroscopy allows continuous, real time measurement of changes in CBV at the bedside. IMPLICATIONS: Near-infrared spectroscopy, a bedside technique, has been used to measure changes in cerebral blood volume in normal subjects. We have used the same technique in anesthetized patients and have shown that, when a patient is placed in the head up position, the decrease in cerebral blood volume is attenuated, relative to normal subjects.

Adult↗

Oncology nurses' experience of dimethyl sulfoxide odor.

This article presents findings of an exploratory descriptive study on the effects of dimethyl sulfoxide (DMSO) odor in an oncology unit. The nursing staff, who had reported their concerns about the unpleasant odor emitted from patients undergoing peripheral stem cell transplantation, initiated the study. A literature review revealed some evidence of the possible ill effects on staff caring for patients having DMSO treatment, but many questions remain unanswered such as what staff experience in dealing with DMSO odor and whether nursing care is affected in any way? Data were collected through interviews with 22 oncology nurses who all had experienced direct and indirect exposure to DMSO odor. Of the 22 nurses interviewed, 20 reported that they found DMSO odor unpleasant and reported experiencing physical symptoms such as headaches and gastrointestinal reactions. The study also revealed a situation in which nurses described odor avoidance and distancing strategies that potentially compromised the nurse-patient relationship.

Cryoprotective Agents↗

Acute effects of bushfires on peak expiratory flow rates in children with wheeze: a time series analysis.

OBJECTIVES: To determine the effects of the January 1994 Sydney bushfire on evening peak expiratory flow rates (PEFR) in children with wheeze. METHODS: Children with a history of wheeze were enrolled in the longitudinal study and completed a daily asthma diary. We obtained daily air pollution, meteorological, pollen and alternaria data. We then used generalised estimating equation techniques to determine associations between the bushfire period and particulate matter less than 10 microns (PM10) and PEFR. RESULTS: The maximum daily PM10 level peaked at 210 ug/m3, which was nearly seven times the usual PM10 level for the rest of January and February 1994. There was no significant association between mean PM10 and PEFR (beta-coefficient = -0.009, p = 0.86). Children without bronchial hyper-reactivity had a significant negative association between PEFR and PM10 (beta-coefficient = -0.1029, p = 0.03). The bushfire period was not significant in any of the models. CONCLUSIONS: We did not find an association between the bushfire period or PM10 and evening PEFR, although in a subgroup of children without bronchial hyper-reactivity, a significant negative association was present between PM10 and evening PEFR. IMPLICATIONS: We conclude that the high levels of particulate pollution caused by the Sydney bushfires did not lead to any clinically significant reductions in PEFR in symptomatic children. Our results have implications for community risk communication during future bushfires.

Air Pollution↗

Is the prophylactic administration of magnesium sulphate in women with pre-eclampsia indicated prior to labour?

OBJECTIVE: To determine whether prophylactic magnesium sulphate is necessary to prevent eclampsia and associated complications among women with pre-eclampsia prior to labour. DESIGN: Case series. SETTING: Tertiary referral centre. POPULATION: Three hundred and eighteen women with pre-eclampsia (blood pressure > or = 140/90 mmHg and > or = 2+ proteinuria) who were not in labour or for planned induction thereof and had not received magnesium sulphate during transfer. METHODS: Clinical evaluation of the pregnant women with careful blood pressure control. Magnesium sulphate was withheld even in the presence of imminent eclampsia. During labour, the option of magnesium sulphate prophylaxis was left to the clinician, but magnesium sulphate was administered in cases of eclampsia. MAIN OUTCOME MEASURES: Eclampsia and related complications. RESULTS: Five women (1.5%) developed eclampsia, although none developed related complications. Women presented at an early gestational age (mean 30 weeks), with high blood pressure, often suffering from headaches. Twenty pregnancies were terminated prior to viability, of which half were terminated for maternal reasons. Ten intrauterine deaths occurred. Most often fetal distress (38.6%) initiated the delivery process, which was mainly by caesarean section (68.5%). With the exception of epigastric discomfort, symptoms and signs of imminent eclampsia decreased after admission. Blood pressure values were significantly lower at delivery although biochemistry results deteriorated from admission to delivery. CONCLUSION: In women with pre-eclampsia prior to labour, where blood pressure control was carefully applied but magnesium sulphate not given, the eclampsia rate was low and eclampsia did not appear to worsen the existing prognosis for mother or fetus.

Adult↗

Nifedipine or prazosin as a second agent to control early severe hypertension in pregnancy: a randomised controlled trial.

OBJECTIVE: To determine whether nifedipine or prazosin is the more appropriate second-line antihypertensive agent in pregnancy. DESIGN: Randomised controlled trial. SETTING: Tygerberg Hospital, a tertiary referral centre. POPULATION: Women with early, severe pre-eclampsia or hypertension in pregnancy, whose blood pressure could not be adequately controlled by methyldopa 2 g/day, but were otherwise stable. METHODS: Nifedipine or prazosin were given and increased as necessary in a stepwise fashion. Once the maximum dose was reached, the other drug was added in a crossover pattern. Failure to control blood pressure, or the onset of maternal/fetal complications were indications for delivery. Patients reaching a minimum gestation of 34 weeks without complications were delivered electively. MAIN OUTCOME MEASURES: Antenatal days gained; major maternal complications and perinatal survival. RESULTS: Days gained on the second antihypertensive agent did not differ significantly (P = 0.9), while more days were gained using nifedipine as the crossover 'third agent' (P = 0.01). In the nifedipine group better renal function was recorded, but more cases with isolated low platelet counts occurred. More cases of pulmonary oedema as well as more nonviable mid-trimester and third trimester intrauterine deaths occurred in the prazosin group. CONCLUSION: Nifedipine and prazosin as second agents allowed comparable amounts of time to be gained, although this changed when used as crossover third-line agents. The efficacy and safety of nifedipine in this study are consistent with the results of other studies. A greater number of intrauterine deaths occurred in the prazosin group.

Antihypertensive Agents↗

Conversion of topoisomerase I cleavage complexes on the leading strand of ribosomal DNA into 5'-phosphorylated DNA double-strand breaks by replication runoff.

Topoisomerase I cleavage complexes can be induced by a variety of DNA damages and by the anticancer drug camptothecin. We have developed a ligation-mediated PCR (LM-PCR) assay to analyze replication-mediated DNA double-strand breaks induced by topoisomerase I cleavage complexes in human colon carcinoma HT29 cells at the nucleotide level. We found that conversion of topoisomerase I cleavage complexes into replication-mediated DNA double-strand breaks was only detectable on the leading strand for DNA synthesis, which suggests an asymmetry in the way that topoisomerase I cleavage complexes are metabolized on the two arms of a replication fork. Extension by Taq DNA polymerase was not required for ligation to the LM-PCR primer, indicating that the 3' DNA ends are extended by DNA polymerase in vivo closely to the 5' ends of the topoisomerase I cleavage complexes. These findings suggest that the replication-mediated DNA double-strand breaks generated at topoisomerase I cleavage sites are produced by replication runoff. We also found that the 5' ends of these DNA double-strand breaks are phosphorylated in vivo, which suggests that a DNA 5' kinase activity acts on the double-strand ends generated by replication runoff. The replication-mediated DNA double-strand breaks were rapidly reversible after cessation of the topoisomerase I cleavage complexes, suggesting the existence of efficient repair pathways for removal of topoisomerase I-DNA covalent adducts in ribosomal DNA.

Camptothecin↗

Effects of massage on physiological restoration, perceived recovery, and repeated sports performance.

BACKGROUND: Despite massage being widely used by athletes, little scientific evidence exists to confirm the efficacy of massage for promoting both physiological and psychological recovery after exercise and massage effects on performance. AIM: To investigate the effect of massage on perceived recovery and blood lactate removal, and also to examine massage effects on repeated boxing performance. METHODS: Eight amateur boxers completed two performances on a boxing ergometer on two occasions in a counterbalanced design. Boxers initially completed performance 1, after which they received a massage or passive rest intervention. Each boxer then gave perceived recovery ratings before completing a second performance, which was a repeated simulation of the first. Heart rates and blood lactate and glucose levels were also assessed before, during, and after all performances. RESULTS: A repeated measures analysis of variance showed no significant group differences for either performance, although a main effect was found showing a decrement in punching force from performance 1 to performance 2 (p<0.05). A Wilcoxon matched pairs test showed that the massage intervention significantly increased perceptions of recovery (p<0.01) compared with the passive rest intervention. A doubly multivariate multiple analysis of variance showed no differences in blood lactate or glucose following massage or passive rest interventions, although the blood lactate concentration after the second performance was significantly higher following massage (p<0.05). CONCLUSIONS: These findings provide some support for the psychological benefits of massage, but raise questions about the benefit of massage for physiological restoration and repeated sports performance.

Adult↗

Knowledge, attitude and practice of smoking among university students of allied health sciences in Japan.

A study was conducted to determine the knowledge, attitude and practice (KAP) of cigarette smoking among freshman students of Tokyo Metropolitan University of Health Sciences. Students were categorized as 'ever-smoker' or 'nonsmoker'. 18.3% of the 356 subjects were categorized as 'ever-smoker'. The two categories were then compared to determine significant differences in health knowledge, attitudes towards health and smoking, smoking perceptions and preferences, knowledge on the economic impact of tobacco and attitudes towards tobacco control measures. In most cases, significant differences were found between the two groups. However, concerning knowledge on the economic impact of tobacco, the majority of both ever-smokers and nonsmokers had poor knowledge. Increased tobacco control education and related efforts are needed as is further research in determining the factors or influences that shape the significant differences found. Such information will be invaluable in formulating appropriate tobacco control measures for the future.

Adult↗

Gimme 5 fruit, juice, and vegetables for fun and health: outcome evaluation.

A theory-based multicomponent intervention (Gimme 5) was designed and implemented to impact fourth- and fifth-grade children's fruit, juice, and vegetable (FJV) consumption and related psychosocial variables. Gimme 5 was a randomized controlled intervention trial with school (n = 16 elementary) as unit of random assignment and analysis. Participants included the cohort of students who were in the third grade in the winter of 1994 and students who joined them in the fourth and fifth grades. The intervention included a curriculum, newsletters, videotapes, and point-of-purchase education. Evaluation included 7-day food records and psychosocial measures from students, telephone interviews with parents, and observational assessments. Favorable results were observed for consumption of FJV combined, FJV consumed at weekday lunch, eating FJV self-efficacy, social norms, asking behaviors, and knowledge. A theory-based school nutrition education program can help change children's FJV consumption and impact factors at home that predispose to FJV consumption, but changes were small, and their persistence is unknown.

Child↗

Gimme 5 fruit and vegetables for fun and health: process evaluation.

Gimme 5 (Georgia) was a school-based nutrition education effectiveness trial to help fourth- and fifth-grade students eat more fruit, 100% juice, and vegetables (FJV). Process evaluation assessed fidelity of implementation, reach, and use of intervention materials and environmental mediators: teacher training, curriculum delivery, participation in family activities, attendance at evening point-of-purchase grocery store activities, and availability and accessibility of FJV at home. Approximately half of the curriculum activities were implemented in fourth and fifth grades. The lowest proportion completed were those most pertinent to behavior change. Eighty-seven percent of parents reported participating in homework activities with their fourth grader, 66% with fifth graders. Sixty-five percent of parents reported viewing a video with their child in both grades. Ten percent attended evening point-of-purchase grocery store activities. The low level of implementation and modest level of participation in family activities suggest that higher levels of behavior change may have occurred if exposure to the intervention had been higher.

Adult↗