Search PubMed⌕ Search

Biomedical subjects

S Ayers

Publications and source records attributed to S Ayers.

34 records · Page 2Linked to original sources
PubMed2000

Characterization of chloramphenicol and florfenicol resistance in Escherichia coli associated with bovine diarrhea.

Florfenicol, a veterinary fluorinated analog of thiamphenicol, is approved for treatment of bovine respiratory pathogens in the United States. However, florfenicol resistance has recently emerged among veterinary Escherichia coli isolates incriminated in bovine diarrhea. The flo gene, which confers resistance to florfenicol and chloramphenicol, has previously been identified in Photobacterium piscicida and Salmonella enterica serovar Typhimurium DT104. The flo gene product is closely related to the CmlA protein identified in Pseudomonas aeruginosa. The cmlA gene confers nonenzymatic chloramphenicol resistance via an efflux mechanism. Forty-eight E. coli isolates recovered from calves with diarrhea, including 41 that were both chloramphenicol and florfenicol resistant, were assayed for the presence of both flo and cmlA genes. Forty-two of the 44 isolates for which florfenicol MICs were > or =16 microg/ml were positive via PCR for the flo gene. All E. coli isolates for which florfenicol MICs were < or =8 microg/ml were negative for the flo gene (n = 4) Twelve E. coli isolates were positive for cmlA, and chloramphenicol MICs for all 12 were > or =32 microg/ml. Additionally, eight isolates were positive for both flo and cmlA, and both florfenicol and chloramphenicol MICs for these isolates were > or =64 microg/ml. DNA sequence analysis of the E. coli flo gene demonstrated 98% identity to the published GenBank sequences of both serovar Typhimurium flo(St) and P. piscicida pp-flo. The flo gene was identified on high-molecular-weight plasmids of approximately 225 kb among the majority of florfenicol-resistant E. coli isolates. However, not all of the florfenicol-resistant E. coli isolates tested contained the large flo-positive plasmids. This suggests that several of the E. coli isolates may possess a chromosomal flo gene. The E. coli flo gene specifies nonenzymatic cross-resistance to both florfenicol and chloramphenicol, and its presence among bovine E. coli isolates of diverse genetic backgrounds indicates a distribution much wider than previously thought.

Animals↗
PubMed1998

Active versus expectant management of third stage of labour: the Hinchingbrooke randomised controlled trial.

BACKGROUND: This study tested the hypotheses that active management of the third stage of labour lowers the rates of primary postpartum haemorrhage (PPH) and longer-term consequences compared with expectant management, in a setting where both managements are commonly practised, and that this effect is not mediated by maternal posture. BACKGROUND: 1512 women judged to be at low risk of PPH (blood loss >500 mL) were randomly assigned active management of the third stage (prophylactic oxytocic within 2 min of baby's birth, immediate cutting and clamping of the cord, delivery of placenta by controlled cord traction or maternal effort) or expectant management (no prophylactic oxytocic, no cord clamping until pulsation ceased, delivery of placenta by maternal effort). Women were also randomly assigned upright or supine posture. Analyses were by intention to treat. FINDINGS: The rate of PPH was significantly lower with active than with expectant management (51 [6.8%] of 748 vs 126 [16.5%] of 764; relative risk 2.42 [95% CI 1.78-3.30], p<0.0001). Posture had no effect on this risk (upright 92 [12%] of 755 vs supine 85 [11%] of 757). Objective measures of blood loss confirmed the results. There was more vomiting in the active group but no other important differences were detected. INTERPRETATION: Active management of the third stage reduces the risk of PPH, whatever the woman's posture, even when midwives are familiar with both approaches. We recommend that clinical guidelines in hospital settings advocate active management (with oxytocin alone). However, decisions about individual care should take into account the weights placed by pregnant women and their caregivers on blood loss compared with an intervention-free third stage.

Constriction↗
PubMed1998

Percentage hypochromic red cells and the response to intravenous iron therapy in anaemic haemodialysis patients.

INTRODUCTION: Iron deficiency is commonly encountered in haemodialysis (HD) patients and may be overcome by i.v. iron therapy. We have examined the percentage hypochromic red cells (%HRC) for predicting response to i.v. iron in subjects with a low serum ferritin. METHODS: Prospective study of i.v. iron saccharate (trivalent iron 200 mg/week for 8 weeks) in anaemic (Hb < 10 g/dl) HD patients with serum ferritin < 100 microg/l despite oral iron therapy. Response to i.v. iron was assessed by comparing Hb at 0 and 8 weeks according to %HRC at baseline (0-3%, 4-9%, > or = 10%). Results are mean+/-1 SD. RESULTS: For all subjects (n=82), Hb and ferritin increased between 0 and 8 weeks (8.9+/-1.0 to 10.1+/-1.4, P<0.0001; 55+/-24 to 288+/-126, P<0.0001). Patients were stratified into three groups according to %HRC at baseline (0-3%, 4-9%, > or = 10%). Hb increased significantly in all three groups. The mean increase in Hb was greater (0-3%, 0.6+/-1.2; 4-9%, 1.2+/-1.0; > or = 10%, 1.6+/-1.4; P=0.02) and the proportion of patients showing a > or = 1 g/dl increase in Hb was greater (0-3%, 27%; 4-9%, 57%; > or = 10%, 67%; P=0.02) in those with the largest %HRC pre-treatment. CONCLUSION: Intravenous iron therapy is effective in improving Hb in anaemic HD patients with a low ferritin. However, the magnitude of this response and the proportion of patients responding is related to the percentage hypochromic red cells prior to treatment.

Anemia↗
PubMed1998

Barbados Low Dose Aspirin Study in Pregnancy (BLASP): a randomised trial for the prevention of pre-eclampsia and its complications.

OBJECTIVE: To determine whether prophylactic, low dose controlled-release aspirin improves outcome for pregnant women and their babies in Barbados. DESIGN: Randomised placebo-controlled trial. SETTING: The Queen Elizabeth Hospital, Barbados. POPULATION: All women attending antenatal clinics between 12 and 32 weeks of gestation were eligible, if without specific contraindications to aspirin and unlikely to deliver immediately. METHODS: Randomisation was computer-generated in the antenatal clinic; 1822 women were allocated to receive 75 mg controlled-release aspirin and 1825 matching placebo. MAIN OUTCOME MEASURES: Proteinuric pre-eclampsia, other pregnancy-induced hypertension, pregnancy duration, birthweight, stillbirths and neonatal deaths, major neonatal events. RESULTS: All but three women from each group were followed up successfully. Forty-four percent were primigravid, and 8% had previous obstetric complications. There were no significant differences between the allocated treatment groups in the incidence of proteinuric pre-eclampsia (40 [2.2%] of those allocated aspirin, compared with 46 [2.5%] allocated placebo), of preterm delivery (255 [14.0%] vs 270 [14.8%]), of birthweight < 1500 g (32 [1.7%] vs 33 [1.8%]) or of stillbirth and neonatal death (44 [2.4%] vs 38 [2.1%]). Aspirin was not associated with excess risk of maternal or fetal bleeding. CONCLUSIONS: The results of this study in Barbados do not support the routine use of low dose aspirin for prevention of pre-eclampsia or its complications, confirming results of previous large trials in other settings.

Adult↗
PubMed1998

The Ipswich Childbirth Study: 1. A randomised evaluation of two stage postpartum perineal repair leaving the skin unsutured.

OBJECTIVE: To evaluate a policy of two stage postpartum perineal repair leaving the skin unsutured. DESIGN: A stratified randomised controlled trial using a 2 x 2 factorial design. SETTING: The maternity unit at Ipswich Hospital NHS Trust, a district general hospital, between 1992 and 1994. SAMPLE: 1780 women requiring surgical repair of episiotomy or first or second degree tear following a spontaneous or simple instrumental delivery. METHODS: A policy of two-stage perineal repair leaving skin unsutured was compared with a policy of three stage repair including skin closure with interrupted or subcuticular sutures. Both groups were assessed by a research midwife, blind to the allocation, completing questionnaires at 24 to 48 hours and 10 days postpartum, and by self-completed questionnaires at three months after birth. MAIN OUTCOME MEASURES: 1. 24 to 48 hours postpartum: perineal pain; healing; 2. 10 days postpartum: perineal pain, healing and removal of sutures; 3. three months postpartum: perineal pain, removal of sutures, resuturing, dyspareunia, and failure to resume pain-free intercourse. RESULTS: Completed questionnaires were returned for 99% of women at both 24 to 48 hours and ten days and by 93% of women three months postpartum. No differences were detected in perineal pain at 24 to 48 hours (62% vs 64%; RR 0.96, 95% CI 0.90-1.03; 2P = 0.3) and 10 days (25% vs 28%; RR 0.90, 95% CI 0.77-1.06; 2P = 0.2). Significantly fewer women allocated to two-stage repair reported tight stitches at ten days (14% vs 18%; RR 0.77, 95% CI 0.62-0.96, 2P = 0.02); similar numbers of repairs were judged to be breaking down (five compared with seven women). At three months postpartum fewer women allocated to the two-stage repair reported perineal pain and more had resumed pain-free intercourse. Amongst women who had resumed intercourse there was a significant difference in dyspareunia (15% vs 19%; RR 0.80, 95% CI 0.65-0.99; 2P = 0.04). Significantly fewer women in the two-stage repair group (7% vs 12%; RR 0.61, 95% CI 0.45-0.83; 2P = < 0.01) reported removal of suture material. Four women in the two-stage repair group had required resuturing, compared with nine allocated to the three-stage repair. CONCLUSIONS: Two-stage repair of perineal trauma leaving the skin unsutured appears to reduce pain and dyspareunia three months postpartum. There are no apparent disadvantages, in particular no evidence of an increased risk of breakdown of the repair and resuturing.

Adult↗
PubMed1998

The Ipswich Childbirth Study: 2. A randomised comparison of polyglactin 910 with chromic catgut for postpartum perineal repair.

OBJECTIVE: To compare polyglactin 910 sutures with chromic catgut sutures for postpartum perineal repair. DESIGN: A stratified randomised controlled trial, using a 2 x 2 factorial design. SETTING: The maternity unit at Ipswich Hospital NHS Trust, a district general hospital, between 1992 and 1994. SAMPLE: 1780 women who had sustained an episiotomy or first or second degree tear following a spontaneous or simple instrumental delivery. METHODS: Policies of repair with polyglactin 910 or chromic catgut were compared. Both groups were assessed by a research midwife completing questionnaires at 24 to 48 hours and at ten days postpartum, and by self-completed questionnaires at three months after birth. MAIN OUTCOME MEASURES: 1. 24 to 48 hours postpartum: perineal pain, healing; 2. ten days postpartum: perineal pain, healing and removal of sutures; 3. three months postpartum: perineal pain, removal of sutures, resuturing, dyspareunia, and failure to resume pain-free intercourse. RESULTS: Completed questionnaires were returned for 99% of women at both 24 to 48 hours and ten days and by 93% of women three months postpartum. The two groups were similar at trial entry. Significantly fewer women allocated to the polyglactin 910 reported pain in the previous 24 hours at both 24 to 48 hours (59% vs 67%; RR 0.89, 95% CI 0.83-0.95; 2P < 0.01), and ten days (24% vs 29%; RR 0.81, 95% CI 0.69-0.95; 2P = 0.01). At three months postpartum there was no clear difference between the groups in terms of perineal pain, dyspareunia or failure to resume pain-free intercourse. More women in the polyglactin 910 group reported that some suture material had been removed (12% vs 7%; RR 1.62, 95% CI 1.19-2.21; 2P < 0.01). Three women in the polyglactin 910 group had required resuturing compared with ten in the chromic catgut group (RR 0.30; 95% CI 0.08-1.09; 2P = 0.1). CONCLUSIONS: Using polyglactin 910 rather than chromic catgut for perineal repair leads to about one fewer women among every 20 having perineal pain and using analgesia ten days postpartum. Its only apparent disadvantage is that more women, again estimated as 1 in 20, report having material removed during healing. Data from this and other trials suggest that for every 100 women repaired with a polyglycolic acid-based material, about one fewer will require resuturing.

Adult↗
PubMed1997

Management of the patient with disruptive vocalization.

Disruptive vocalization (DV) is a common problem in the management of cognitively and physically impaired older people. This article reports the results of a consensus meeting convened to provide guidelines for clinicians and recommendations for researchers in this difficult and little-studied behavioral problem. DV arises largely in people with cognitive impairment and generally reflects an underlying need or discomfort. A variety of factors can precipitate and aggravate DV; the key to management is appropriate identification of all possible factors and development of an individualized treatment plan.

Aged↗
PubMed1992

A randomized controlled trial to compare three types of fetal scalp electrode.

OBJECTIVES: To compare three scalp electrodes in respect of need for reapplication, trace quality and scalp trauma. DESIGN: Randomized controlled trial. SETTING: Maternity Unit, Royal Berkshire Hospital, Reading. PARTICIPANTS: 780 women in labour at term, with cephalic fetal presentation, deemed to require electronic fetal heart rate monitoring using a scalp electrode. INTERVENTIONS: Three types of fetal scalp electrode: Rocket-Rolon (double-helix spiral); Hewlett-Packard (double-helix spiral); and Surgicraft-Copeland (clip). MAIN OUTCOME MEASURES: Need for more than one electrode; reason for replacement; trace quality; scalp trauma; direct financial costs. RESULTS: Reapplication was significantly least likely in the Surgicraft-Copeland group (odds ratio vs Hewlett-Packard = 0.61, 95% CI 0.41-0.90; odds ratio vs Rocket-Rolon = 0.43, 95% CI = 0.29-0.62). This reflected a much lower rate of replacement because of detachment. The Hewlett-Packard was, however, least likely to be replaced because of poor trace quality. Interpretable traces were equally common, but trace quality tended to be superior in the Hewlett-Packard group. There was no serious scalp trauma. Difficulty removing the electrode was least often reported in the Hewlett-Packard group, and a mark on the scalp persisted least often in the Rocket-Rolon group. CONCLUSIONS: The Surgicraft-Copeland performed the best overall, and particularly in respect of attachment to the scalp. It appears to be the electrode of choice of the three tested.

Adult↗