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I Roberts

Publications and source records attributed to I Roberts.

At least 91 records · Page 5Linked to original sources
PubMed2000

Human albumin solution for resuscitation and volume expansion in critically ill patients. The Albumin Reviewers.

BACKGROUND: Human albumin solutions are used in a range of medical and surgical problems. Licensed indications are the emergency treatment of shock and other conditions where restoration of blood volume is urgent, burns, and hypoproteinaemia. Human albumin solutions are more expensive than other colloids and crystalloids. OBJECTIVES: To quantify the effect on mortality of human albumin and plasma protein fraction (PPF) administration in the management of critically ill patients. SEARCH STRATEGY: We searched the Cochrane Injuries Group trials register, Cochrane Controlled Trials Register, Medline, Embase and BIDS Index to Scientific and Technical Proceedings. Reference lists of trials and review articles were checked, and authors of identified trials were contacted. The search was last updated in November 1999. SELECTION CRITERIA: Randomised controlled trials comparing albumin/PPF with no albumin/PPF, or with a crystalloid solution, in critically ill patients with hypovolaemia, burns or hypoalbuminaemia. DATA COLLECTION AND ANALYSIS: We collected data on the participants, albumin solution used, mortality at the end of follow up, and quality of allocation concealment. Analysis was stratified according to patient type. We assessed publication bias using the regression test for funnel plot asymmetry. MAIN RESULTS: We found 30 trials meeting the inclusion criteria and reporting death as an outcome. There were 156 deaths among 1419 trial participants. For each patient category the risk of death in the albumin treated group was higher than in the comparison group. For hypovolaemia the relative risk of death following albumin administration was 1.46 (95% confidence interval 0.97 to 2.22), for burns the relative risk was 2.40 (1.11 to 5.19), and for hypoalbuminaemia the relative risk was 1.69 (1.07 to 2.67). The pooled relative risk of death with albumin administration was 1.68 (1.26 to 2.23). Overall, the risk of death in patients receiving albumin was 14% compared to 8% in the control groups, an increase in the risk of death of 6% (3% to 9%). These data suggest that for every 17 critically ill patients treated with albumin there is one additional death. REVIEWER'S CONCLUSIONS: There is no evidence that albumin administration reduces the risk of death in critically ill patients with hypovolaemia, burns or hypoalbuminaemia, and a strong suggestion that it may increase the risk of death. These data suggest that the use of human albumin in critically ill patients should be urgently reviewed and that it should not be used outside the context of a rigorously conducted randomised controlled trial.

Blood Proteins↗
PubMed2000

Aminosteroids for acute traumatic brain injury.

BACKGROUND: Traumatic brain injury is a leading cause of premature death and disability. Post-traumatic membrane lipid peroxidation has been proposed as one mechanism leading to secondary brain damage following head injury. Aminosteroids have been shown to inhibit lipid peroxidation in laboratory animals and have the potential to improve outcome following head injury. OBJECTIVES: To quantify the effectiveness and safety of aminosteroids in the treatment of acute traumatic brain injury. SEARCH STRATEGY: We searched the Cochrane Injuries Group trials register, The Cochrane Controlled Trials Register, MEDLINE and EMBASE. We contacted experts in the field and the company that manufactures tirilazad. SELECTION CRITERIA: We sought to identify all randomised controlled trials of aminosteroids versus placebo in the treatment of acute traumatic brain injury. Studies using a quasi random form of allocation, such as alternation, were excluded from the review. DATA COLLECTION AND ANALYSIS: One reviewer examined the electronic search results for reports of possibly relevant trials for retrieval in full. Two reviewers (IR and PA) applied the selection criteria independently to the trial report, with no disagreement. MAIN RESULTS: Two randomised controlled trials have examined the effect of the aminosteroid tirilazad mesylate on death and disability following head injury. To date, only the results of one of these trials are available for analysis. The risk of death in patients treated with tirilazad was almost identical to those given placebo RR=1.05 (95% confidence interval 0.86 to 1.29). The risk of death and severe disability in patients treated with tirilazad was again almost identical to those given placebo RR=1.07 (95% confidence interval 0.93 to 1.23). REVIEWER'S CONCLUSIONS: There is no evidence to support the routine use of aminosteroids in the management of traumatic head injury. On the basis of the existing evidence from randomised trials of aminosteroids in head injury it is not possible to refute the possibility of moderate but potentially clinically important benefits or harms. A further randomised controlled trial of tirilazad mesylate with 1156 participants has been completed, the results of which should become available in the near future.

Brain Injuries↗
PubMed2000

Nutritional support for head-injured patients.

BACKGROUND: Head injury increases the body's metabolic responses, and therefore nutritional demands. Provision of an adequate supply of nutrients is associated with improved outcome. The best route for administering nutrition (parenterally (TPN) or enterally (EN)), and the best timing of administration (e.g early versus late) of nutrients needs to be established. OBJECTIVES: To quantify the effect on mortality and morbidity of alternative strategies of providing nutritional support following head injury. SEARCH STRATEGY: Trials were identified by computerised searches of the Injuries Group specialised register, Cochrane Controlled Trials Register, MEDLINE, EMBASE and BIDS Index to Scientific and Technical Proceedings, and by checking the reference lists of trials and review articles. SELECTION CRITERIA: Randomised controlled trials of nutritional support following acute traumatic brain injury. DATA COLLECTION AND ANALYSIS: Two reviewers independently abstracted data and assessed trial quality. Information was collected on death, disability, and incidence of infection. If trial quality was unclear, or if there were missing outcome data, trialists were contacted in an attempt to get further information. MAIN RESULTS: The timing of support: early versus delayed Of the six trials addressing the timing of support, data on mortality were obtained for all six trials, with a total of 257 patients. The relative risk (RR) for death with early nutritional support was 0.71 (95% CI 0.43 to 1.16). Data on disability were available for three trials. The RR for death or disability at the end of follow-up was 0.75 (0.50 to 1.11). The route of feeding: parenteral versus enteral Six trials compared parenteral versus enteral nutrition. Because early support often involves parenteral nutrition, three of the six trials are also included in the previous analyses. Five trials (207 participants) reported mortality. The RR for mortality at the end of follow-up period was 0.66 (0.41 to 1.07). Two trials provided data on death and disability. The RR was 0.69 (95%Cl 0.40 to 1.19). 3. Enteral nutrition: jejunal versus gastric. There was one trial with no deaths and the RR is not estimable. REVIEWER'S CONCLUSIONS: This review suggests that early feeding may be associated with a trend towards better outcomes in terms of survival and disability. Further trials are required. These trials should report not only nutritional outcomes but also the effect on death and disability.

Craniocerebral Trauma↗
PubMed2000

Medical anti-shock trousers (pneumatic anti-shock garments) for circulatory support in patients with trauma.

BACKGROUND: Medical antishock trousers (MAST) have been used to increase venous return to the heart until definitive care could be given. This, combined with compression of blood vessels, is believed to cause the movement of blood from the lower body to the brain, heart and lungs. However, the equipment is expensive, and may have adverse effects. OBJECTIVES: To quantify the effect on mortality and morbidity of the use of medical anti-shock trousers (MAST)/ pneumatic anti-shock garments (PASG) in patients following trauma. SEARCH STRATEGY: Trials were identified by searches of the Cochrane Injuries Group Trials Register, the Cochrane Controlled Trials Register, MEDLINE, EMBASE, BIDS ISI Service and Science Citation Index. References in relevant papers identified were followed up. A citation analysis of references to randomised controlled trials was conducted using the Science Citation Index. Authors of identified trials were contacted and asked about any other trials that may have been conducted, whether published or unpublished. SELECTION CRITERIA: Randomised and quasi-randomised trials of MAST/PASG in patients following trauma (excluding fractures of the extremities in which MAST/PASG may be used as a splint). DATA COLLECTION AND ANALYSIS: Data were extracted independently by two reviewers. Data were collected on mortality, duration of hospitalisation and ICU stay, and quality of allocation concealment. MAIN RESULTS: Two trials were identified that met the inclusion criteria. These trials included 1202 randomised patients in total; however, data for only 1075 of these were available. The relative risk of death with MAST was 1.13 (95% CI 0.97 to 1.32). Duration of hospitalisation and of intensive care unit stay was longer in the MAST treated group. The weighted mean difference in the length of intensive care unit stay was 1.7 days (95% CI 0.33 to 2.98). REVIEWER'S CONCLUSIONS: There is no evidence to suggest that MAST/PASG application reduces mortality, length of hospitalisation or length of ICU stay in trauma patients and it is possible that it may increase these. These data do not support the continued use of MAST/PASG in the situation described. However, it should be recognised that, due to the poor quality of the trials, conclusions should be drawn with caution.

Bandages↗
PubMed2000

Interventions for preventing injuries in problem drinkers.

OBJECTIVES: To assess the effect of interventions for problem drinking on subsequent injury risk. SEARCH STRATEGY: Data Sources.- Twelve computerized databases: MEDLINE (1966-8/96), EMBASE (1982-1/97), Cochrane Controlled Trials Register (1997, issue #1), PSYCHINFO (1967-1/97), CINAHL (1982-10/96), ERIC (1966-12/96), Dissertation Abstracts International (1861-11/96), IBSS (1961-1/97), ISTP (1982-1/97) and three specialized transportation databases, using terms for problem drinking combined with terms for controlled trials; bibliographies of relevant trials; and contact with authors and government agencies. SELECTION CRITERIA: Data Selection.- Randomized controlled trials of interventions among particiapnts with problem drinking, which are intended to reduce alcohol consumption or to prevent injuries or their antecedents, and which measured injury-related outcomes. Of 7014 studies identified, 19 (0. 3%) met the inclusion criteria. DATA COLLECTION AND ANALYSIS: Data Extraction.- Two authors extracted data on participants, interventions, follow-up, allocation concealment, and outcomes, and independently rated allocation concealment quality. MAIN RESULTS: Data Synthesis.- In completed trials, interventions for problem drinking were associated with reduced suicide attempts, domestic violence, falls, drinking-related injuries, and injury hospitalizations and deaths, with reductions ranging from 27-65%. Several interventions among convicted drunk drivers reduced motor vehicle crashes and injuries. Because few trials were sufficiently large to assess effects on injuries, individual effect estimates were imprecise. We did not combine the results quantitatively because the interventions, patient populations, and outcomes were so diverse. REVIEWER'S CONCLUSIONS: Conclusion.- Interventions for problem drinking may reduce injuries and their antecedents. Because injuries account for much of the morbidity and mortality from problem drinking, further studies are warranted to evaluate the effect of treating problem drinking on injuries.

Accident Prevention↗
PubMed2000

Hypertonic versus isotonic crystalloid for fluid resuscitation in critically ill patients.

BACKGROUND: Hypertonic solutions are considered to have a greater ability to expand blood volume and thus elevate blood pressure and can be administered as a small volume infusion over a short time period. On the other hand, the use of hypertonic solutions for volume replacement may also have important disadvantages. OBJECTIVES: To determine whether hypertonic crystalloid decreases mortality in patients with hypovolaemia with and without head injuries. SEARCH STRATEGY: We searched MEDLINE, EMBASE, The Cochrane Controlled Trials Register and the Specialised register of the Injuries Group. We checked reference lists of all articles identified and searched the National Research Register. SELECTION CRITERIA: Randomised trials comparing hypertonic to isotonic crystalloid in patients with trauma, burns or undergoing surgery. DATA COLLECTION AND ANALYSIS: Two authors independently extracted the data and assessed the quality of the trials. MAIN RESULTS: Sixteen trials were identified with a total of 837 participants. Data on death were obtained in twelve of the studies. Only one trial reported data on disability. The pooled RR for death in trauma patients was 0.84 (95% CI 0.61-1.16), and in patients with burns 1.49 (95% CI 0.56-3.95), and in patients undergoing surgery 0.62 (95% cI 0.08-4.57). In the one trial that gave data on disability using the Glasgow Outcome Scale the relative risk was 0.99 (95% CI 0.06-15.93). REVIEWER'S CONCLUSIONS: This review does not give us enough data to be able to say whether hypertonic crystalloid is better than isotonic crystalloid for the resuscitation of patients with trauma, burns, or those undergoing surgery. However, the confidence intervals are wide and do not exclude clinically significant differences. Further trials are needed comparing hypertonic to isotonic crystalloid. Trials need to be large enough to detect a clinically important difference.

Crystalloid Solutions↗
PubMed2000

IgA myeloma of donor origin arising 7 years after allogeneic renal transplant.

We report the case of a 38-year-old man who developed IgA myeloma of donor origin 7 years after allogeneic renal transplant. The diagnosis of multiple myeloma was unequivocal and based on positive results from serum electrophoresis, skeletal survey and bone marrow investigations. The donor origin of the myeloma cells was confirmed by DNA fingerprinting. We believe this is the first reported case of disseminated multiple myeloma of donor origin developing after allogeneic renal transplant and, as such, gives some insight into the natural history and biology of the disease.

Adult↗
PubMed2000

Smacking.

Explore the source record for details and available documents.

Humans↗
PubMed2000

A potato alpha-glucosidase gene encodes a glycoprotein-processing alpha-glucosidase II-like activity. Demonstration of enzyme activity and effects of down-regulation in transgenic plants.

In order to elucidate more fully the function of a potato gene (MAL1) encoding alpha-glucosidase activity, transgenic plants in which MAL1 expression was down-regulated were generated using antisense technology. In transgenic lines severely down-regulated in the expression of MAL1, total alpha-glucosidase activity was not decreased in leaves and tubers, and the contents of starch, glucose, fructose and sucrose remained unchanged in tubers. Phylogenetic analysis indicated that the MAL1 gene product was more similar to the glycoprotein-processing alpha-glucosidase II of mammalian and yeast origin than to other plant alpha-glucosidases. Using [14C-Glc]-labelled Glc2Man9GlcNAc2 as a substrate, it was demonstrated that glucosidase II activity was markedly down-regulated in microsomes isolated from tubers of four independent antisense lines studied in detail, strongly suggesting that MAL1 encodes glucosidase II activity. In field trials (but not in the glasshouse), MAL1 down-regulation produced an extremely stunted phenotype - the leaves were curled and tuber yield was decreased by 90% compared to control values. Microscopic analysis of leaves revealed significant differences between the antisense and control samples. Plants with down-regulated glucosidase II activity showed a greater degree of plasmolysis, and an increase in the size of mesophyll intracellular spaces. Analysis of cell walls also indicated changes in structure as a result of MAL1 down-regulation. In leaves from four antisense lines, the steady-state transcript level corresponding to the endoplasmic reticulum chaperone, BiP, was enhanced. This is diagnostic of stress in the endoplasmic reticulum.

Carbohydrate Metabolism↗
PubMed2000

Molecular cytogenetic analysis of breast cancer cell lines.

The extensive chromosome rearrangements of breast carcinomas must contribute to tumour development, but have been largely intractable to classical cytogenetic banding. We report here the analysis by 24-colour karyotyping and comparative genomic hybridization (CGH) of 19 breast carcinoma cell lines and one normal breast epithelial cell line, which provide model examples of karyotype patterns and translocations present in breast carcinomas. The CGH was compared with CGH of 106 primary breast cancers. The lines varied from perfectly diploid to highly aneuploid. Translocations were very varied and over 98% were unbalanced. The most frequent in the carcinomas were 8;11 in five lines; and 8;17, 1;4 and 1;10 in four lines. The most frequently involved chromosome was 8. Several lines showed complex multiply-translocated chromosomes. The very aneuploid karyotypes appeared to fall into two groups that evolved by different routes: one that steadily lost chromosomes and at one point doubled their entire karyotype; and another that steadily gained chromosomes, together with abnormalities. All karyotypes fell within the range seen in fresh material and CGH confirmed that the lines were broadly representative of fresh tumours. The karyotypes provide a resource for the cataloguing and analysis of translocations in these tumours, accessible at http://www.path.cam.ac.uk/ approximately pawefish.

Adult↗
PubMed2000

Mesenteric venous thrombosis: a diagnosis not to be missed!

Mesenteric venous thrombosis (MVT), an uncommon but important clinical entity, is one possible cause of ischemia or infarction of the small intestine. Diagnosis of this condition is sometimes difficult and treatment is often delayed because patients usually present with nonspecific abdominal symptoms. The hallmark is pain that is out of proportion to the physical findings. We report two cases of MVT, where the patients initially presented with vague abdominal symptoms. Diagnosis was made on the basis of computed tomography of the abdomen showing thrombus within the superior mesenteric vein. A search for a precipitating condition revealed no evidence of a hypercoagulable state, myeloproliferative disorder, or malignancy. These cases illustrate well the nonspecific clinical presentation of MVT. A high index of suspicion, recognition of known risk factors, or a previous history of venous thrombosis coupled with a history of nonspecific abdominal symptoms should alert clinicians to the possibility of MVT. Early diagnosis and prompt anticoagulation are the mainstay of therapy unless there are signs of peritonitis that necessitate surgical resection of the infarcted bowel.

Abdominal Pain↗
PubMed2000

Urban residential fire and flame injuries: a population based study.

BACKGROUND: Fires are a leading cause of death, but non-fatal injuries from residential fires have not been well characterised. METHODS: To identify residential fire injuries that resulted in an emergency department visit, hospitalisation, or death, computerised databases from emergency departments, hospitals, ambulance and helicopter services, the fire department, and the health department, and paper records from the local coroner and fire stations were screened in a deprived urban area between June 1996 and May 1997. RESULT: There were 131 fire related injuries, primarily smoke inhalation (76%), an incidence of 36 (95% confidence interval (CI) 30 to 42)/100,000 person years. Forty one patients (32%) were hospitalised (11 (95% CI 8 to 15)/100,000 person years) and three people (2%) died (0.8 (95% CI 0.2 to 2.4)/100,000 person years). Injury rates were highest in those 0-4 (68 (95% CI 39 to 112)/100,000 person years) and > or = 85 years (90 (95% CI 29 to 213)/100,000 person years). Rates did not vary by sex. Leading causes of injury were unintentional house fires (63%), assault (8%), clothing and nightwear ignition (6%), and controlled fires (for example, gas burners) (4%). Cooking (31%) and smoker's materials (18%) were leading fire sources. CONCLUSIONS: Because of the varied causes of fire and flame injuries, it is likely that diverse interventions, targeted to those at highest risk, that is, the elderly, young children, and the poor, may be required to address this important public health problem.

Accidents, Home↗
PubMed2000

Randomisation and resource allocation: a missed opportunity for evaluating health care and social interventions.

Equipoise is widely regarded to be an essential prerequisite for the ethical conduct of a randomised controlled trial. There are some circumstances however, under which it is acceptable to conduct a randomised controlled trial (RCT) in the absence of equipoise. Limited access to the preferred intervention is one such circumstance. In this paper we present an example of a randomised trial in which access to the preferred intervention, preschool education, was severely limited by resource constraints. The ethical issues that arise when conducting randomised trials in health care are considered in the context of trials of social interventions. In health, education and social welfare, effective interventions are frequently limited due to budgetary constraints. Explicit acknowledgement of the need to ration interventions, and the use of random allocation to do this even in the absence of equipoise, would facilitate learning more about the effects of these interventions.

Behavioral Research↗
PubMed2000

Randomized double-blind controlled trial comparing the effects of ibuprofen with indomethacin on cerebral hemodynamics in preterm infants with patent ductus arteriosus.

A prospective randomized controlled trial was performed to compare the effects of ibuprofen with indomethacin on cerebral hemodynamics measured using near infrared spectroscopy in preterm infants during treatment for patent ductus arteriosus. Infants were randomly assigned to three intravenous doses of either indomethacin (0.20-0.25 mg/kg, 12 hourly) or ibuprofen (5-10 mg/kg, 24 hourly) and also received a dose of saline. The primary end points of the study were the effects of the first dose on cerebral blood flow (CBF) and cerebral blood volume. Fifteen infants received indomethacin and 18 received ibuprofen. The group mean (SD) values for CBF (mL x 100 g(-1) x min(-1)) before and after the first dose of indomethacin were 13.6 (4.1) and 8.3 (3.1), respectively, the change being significant (p<0.001). In contrast, no significant changes in CBF were observed with the first dose of ibuprofen, the respective before and after values being 13.3 (3.2) and 14.9 (4.7) mL x 100 g(-1) x min(-1). The median (interquartile range) value for change in cerebral blood volume (mL/100 g) after the first dose in the indomethacin group was -0.4 (-0.3 to -0.6) and in the ibuprofen group was 0.0 (0.1 to -0.1), the difference between the two groups being significant (p<0.001). Cerebral oxygen delivery changed significantly after the first dose in the indomethacin group but not in the ibuprofen group. Significant reductions in CBF, cerebral blood volume, and cerebral oxygen delivery also occurred after the 24-h dose of indomethacin, but there were no significant changes after the 48-h dose of saline in the indomethacin group or after the 24- and 48-h doses of ibuprofen. The patent ductus arteriosus closure rates after indomethacin and ibuprofen were 93 and 78%, respectively. We conclude that ibuprofen, unlike indomethacin, has no adverse effects on cerebral hemodynamics and appears to mediate patent ductus arteriosus closure.

Brain↗