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1.
Appl Radiat Isot ; 118: 43-55, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27611080

ABSTRACT

In order to efficiently remove of uranium anionic species (which are the most dominant species of uranium in natural water at neutral pH) from contaminated waters, nano-NaX zeolite was synthesized and then modified using various divalent cations (Mg2+, Ca2+, Mn2+) and ZnO nanoparticles (from 1.7 to 10.3wt%). Different characterization techniques of XRF, XRD, FE-SEM, TEM, FT-IR, and AAS were used to characterize the final synthesized absorbents. Sorption experiments by batch technique were done to study the effect of solid-liquid ratio, initial uranium concentration, contact time and temperature under neutral condition of pH and presence of all anions and cations which are available in the waters. Results showed that although nano-NaX zeolite due to its negative framework charge had a low sorption capacity for adsorption of uranium anionic species, but modification of parent nano-NaX zeolite with ZnO nanoparticles and various cations effectively improved its uranium adsorption capacity. Also, results showed that under optimum condition of pH=7.56, contact time of 60min at 27°C with solid-liquid ratio of 20g/L a maximum uranium removal efficiency of 99.7% can be obtained in the presence of all anions and cations which are available in the drinking waters by NaX/ZnO nanocomposite.


Subject(s)
Metal Nanoparticles/chemistry , Ultrafiltration/methods , Uranium/chemistry , Uranium/isolation & purification , Water Pollutants, Radioactive/isolation & purification , Water Purification/methods , Zeolites/chemistry , Adsorption , Ions/chemistry , Ions/isolation & purification , Metal Nanoparticles/ultrastructure , Particle Size , Water Pollutants, Radioactive/chemistry , Zinc Oxide/chemistry
2.
BJOG ; 123(11): 1745-52, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27558956

ABSTRACT

BACKGROUND: Postpartum haemorrhage is the leading cause of maternal mortality. Tranexamic acid (TXA) reduces surgical haemorrhage and the risk of death in bleeding trauma patients. OBJECTIVES: To assess the effects of TXA on risk of postpartum haemorrhage and other clinically relevant outcomes. SEARCH STRATEGY: We searched the MEDLINE, CENTRAL, EMBASE, PubMed, ClinicalTrials.gov and WHO ICTRP electronic databases to May 2015. SELECTION CRITERIA: Randomised controlled trials comparing TXA with no TXA or placebo in women giving birth vaginally or by caesarean section. DATA COLLECTION AND ANALYSIS: Two authors extracted data and assessed the risk of bias for each trial. Because of data concerns we did not conduct a meta-analysis. MAIN RESULTS: We found 26 trials including a total of 4191 women. Examination of the trial reports raised concerns about the quality of the data. Eight trial reports contained identical or similar text and there were important data inconsistencies in several trials. Two trials did not have ethics committee approval. Meta-analysis of baseline variables suggested that randomisation was inadequate in many trials. CONCLUSIONS: There is no reliable evidence that TXA prevents postpartum haemorrhage during childbirth. Many of the trials conducted to date are small, low quality and contain serious flaws. TWEETABLE ABSTRACT: No evidence that TXA prevents postpartum haemorrhage. Existing trials are unreliable, with serious flaws.


Subject(s)
Antifibrinolytic Agents/administration & dosage , Delivery, Obstetric/adverse effects , Parturition/drug effects , Postpartum Hemorrhage/prevention & control , Tranexamic Acid/administration & dosage , Adult , Female , Humans , Postpartum Hemorrhage/etiology , Pregnancy , Randomized Controlled Trials as Topic , Treatment Outcome
4.
Genome Announc ; 1(6)2013 Nov 21.
Article in English | MEDLINE | ID: mdl-24265497

ABSTRACT

Between November 2010 and April 2011, 11 cases of cholera were identified and associated with the consumption of raw oysters harvested from Apalachicola Bay, Florida. The etiological agent was the ctxAB-positive Vibrio cholerae serogroup O75. The genome sequences of the isolates provide useful information and are deposited in the public genome databases.

5.
Health Technol Assess ; 17(24): 1-45, v-vi, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23782457

ABSTRACT

BACKGROUND: Severe bleeding accounts for about one-third of in-hospital trauma deaths. Patients with a high baseline risk of death have the most to gain from the use of life-saving treatments. An accurate and user-friendly prognostic model to predict mortality in bleeding trauma patients could assist doctors and paramedics in pre-hospital triage and could shorten the time to diagnostic and life-saving procedures such as surgery and tranexamic acid (TXA). OBJECTIVES: The aim of the study was to develop and validate a prognostic model for early mortality in patients with traumatic bleeding and to examine whether or not the effect of TXA on the risk of death and thrombotic events in bleeding adult trauma patients varies according to baseline risk. DESIGN: Multivariable logistic regression and risk-stratified analysis of a large international cohort of trauma patients. SETTING: Two hundred and seventy-four hospitals in 40 high-, medium- and low-income countries. PARTICIPANTS: We derived prognostic models in a large placebo-controlled trial of the effects of early administration of a short course of TXA [Clinical Randomisation of an Antifibrinolytic in Significant Haemorrhage (CRASH-2) trial]. The trial included 20,127 trauma patients with, or at risk of, significant bleeding, within 8 hours of injury. We externally validated the model on 14,220 selected trauma patients from the Trauma Audit and Research Network (TARN), which included mainly patients from the UK. We examined the effect of TXA on all-cause mortality, death due to bleeding and thrombotic events (fatal and non-fatal myocardial infarction, stroke, deep-vein thrombosis and pulmonary embolism) within risk strata in the CRASH-2 trial data set and we estimated the proportion of premature deaths averted by applying the odds ratio (OR) from the CRASH-2 trial to each of the risk strata in TARN. INTERVENTIONS: For the stratified analysis according baseline risk we considered the intervention TXA (1 g over 10 minutes followed by 1 g over 8 hours) or matching placebo. MAIN OUTCOME MEASURES: For the prognostic models we included predictors for death in hospital within 4 weeks of injury. For the stratified analysis we reported ORs for all causes of death, death due to bleeding, and fatal and non-fatal thrombotic events associated with the use of TXA according to baseline risk. RESULTS: A total of 3076 (15%) patients died in the CRASH-2 trial and 1705 (12%) in the TARN data set. Glasgow Coma Scale score, age and systolic blood pressure were the strongest predictors of mortality. Discrimination and calibration were satisfactory, with C-statistics > 0.80 in both CRASH-2 trial and TARN data sets. A simple chart was constructed to readily provide the probability of death at the point of care, while a web-based calculator is available for a more detailed risk assessment. TXA reduced all-cause mortality and death due to bleeding in each stratum of baseline risk. There was no evidence of heterogeneity in the effect of TXA on all-cause mortality (p-value for interaction = 0.96) or death due to bleeding (p= 0.98). There was a significant reduction in the odds of fatal and non-fatal thrombotic events with TXA (OR = 0.69, 95% confidence interval 0.53 to 0.89; p= 0.005). There was no evidence of heterogeneity in the effect of TXA on the risk of thrombotic events (p= 0.74). CONCLUSIONS: This prognostic model can be used to obtain valid predictions of mortality in patients with traumatic bleeding. TXA can be administered safely to a wide spectrum of bleeding trauma patients and should not be restricted to the most severely injured. Future research should evaluate whether or not the use of this prognostic model in clinical practice has an impact on the management and outcomes of trauma patients.


Subject(s)
Antifibrinolytic Agents/therapeutic use , Hemorrhage/mortality , Tranexamic Acid/therapeutic use , Wounds and Injuries/complications , Adult , Aged , Female , Hemorrhage/diagnosis , Hemorrhage/drug therapy , Humans , Male , Middle Aged , Models, Theoretical , Prognosis , Reproducibility of Results , Risk Factors , Wounds and Injuries/drug therapy
6.
Health Technol Assess ; 17(10): 1-79, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23477634

ABSTRACT

BACKGROUND: Among trauma patients who survive to reach hospital, exsanguination is a common cause of death. A widely practicable treatment that reduces blood loss after trauma could prevent thousands of premature deaths each year. The CRASH-2 trial aimed to determine the effect of the early administration of tranexamic acid on death and transfusion requirement in bleeding trauma patients. In addition, the effort of tranexamic acid on the risk of vascular occlusive events was assessed. OBJECTIVE: Tranexamic acid (TXA) reduces bleeding in patients undergoing elective surgery. We assessed the effects and cost-effectiveness of the early administration of a short course of TXA on death, vascular occlusive events and the receipt of blood transfusion in trauma patients. DESIGN: Randomised placebo-controlled trial and economic evaluation. Randomisation was balanced by centre, with an allocation sequence based on a block size of eight, generated with a computer random number generator. Both participants and study staff (site investigators and trial co-ordinating centre staff) were masked to treatment allocation. All analyses were by intention to treat. A Markov model was used to assess cost-effectiveness. The health outcome was the number of life-years (LYs) gained. Cost data were obtained from hospitals, the World Health Organization database and UK reference costs. Cost-effectiveness was measured in international dollars ($) per LY. Deterministic and probabilistic sensitivity analyses were performed to test the robustness of the results to model assumptions. SETTING: Two hundred and seventy-four hospitals in 40 countries. PARTICIPANTS: Adult trauma patients (n = 20,211) with, or at risk of, significant bleeding who were within 8 hours of injury. INTERVENTIONS: Tranexamic acid (loading dose 1 g over 10 minutes then infusion of 1 g over 8 hours) or matching placebo. MAIN OUTCOME MEASURES: The primary outcome was death in hospital within 4 weeks of injury, and was described with the following categories: bleeding, vascular occlusion (myocardial infarction, stroke and pulmonary embolism), multiorgan failure, head injury and other. RESULTS: Patients were allocated to TXA (n = 10,096) and to placebo (n = 10,115), of whom 10,060 and 10,067 patients, respectively, were analysed. All-cause mortality at 28 days was significantly reduced by TXA [1463 patients (14.5%) in the TXA group vs 1613 patients (16.0%) in the placebo group; relative risk (RR) 0.91; 95% confidence interval (CI) 0.85 to 0.97; p = 0.0035]. The risk of death due to bleeding was significantly reduced [489 patients (4.9%) died in the TXA group vs 574 patients (5.7%) in the placebo group; RR 0.85; 95% CI 0.76 to 0.96; p = 0.0077]. We recorded strong evidence that the effect of TXA on death due to bleeding varied according to the time from injury to treatment (test for interaction p < 0.0001). Early treatment (≤ 1 hour from injury) significantly reduced the risk of death due to bleeding [198 out of 3747 patients (5.3%) died in the TXA group vs 286 out of 3704 patients (7.7%) in the placebo group; RR 0.68; 95% CI 0.57 to 0.82; p < 0.0001]. Treatment given between 1 and 3 hours also reduced the risk of death due to bleeding [147 out of 3037 patients (4.8%) died in the TXA group vs 184 out of 2996 patients (6.1%) in the placebo group; RR 0.79; 95% CI 0.64 to 0.97; p = 0.03]. Treatment given after 3 hours seemed to increase the risk of death due to bleeding [144 out of 3272 patients (4.4%) died in the TXA group vs 103 out of 3362 patients (3.1%) in the placebo group; RR 1.44; 95% CI1.12 to 1.84; p = 0.004]. We recorded no evidence that the effect of TXA on death due to bleeding varied by systolic blood pressure, Glasgow Coma Scale score or type of injury. Administering TXA to bleeding trauma patients within 3 hours of injury saved an estimated 755 LYs per 1000 trauma patients in the UK. The cost of giving TXA to 1000 patients was estimated at $30,830. The incremental cost of giving TXA compared with not giving TXA was $48,002. The incremental cost per LY gained of administering TXA was $64. CONCLUSIONS: Early administration of TXA safely reduced the risk of death in bleeding trauma patients and is highly cost-effective. Treatment beyond 3 hours of injury is unlikely to be effective. Future work [the Clinical Randomisation of an Antifibrinolytic in Significant Head injury-3 (CRASH-3) trial] will evaluate the effectiveness and safety of TXA in the treatments of isolated traumatic brain injury (http://crash3.lshtm.ac.uk/). TRIAL REGISTRATION: Current Controlled Trials ISRCTN86750102, ClinicalTrials.gov NCT00375258 and South African Clinical Trial Register DOH-27-0607-1919. FUNDING: The project was funded by the Bupa Foundation, the J P Moulton Charitable Foundation and the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 17, No. 10. See HTA programme website for further project information.


Subject(s)
Antifibrinolytic Agents/therapeutic use , Blood Transfusion , Hemorrhage/mortality , Hemorrhage/prevention & control , Thrombosis/prevention & control , Tranexamic Acid/therapeutic use , Adult , Confidence Intervals , Craniocerebral Trauma/mortality , Female , Hospital Mortality , Humans , Internationality , Male , Middle Aged , Multiple Organ Failure/mortality , Multiple Organ Failure/prevention & control , Outcome Assessment, Health Care/statistics & numerical data , Thrombosis/mortality , Wounds, Nonpenetrating/mortality , Wounds, Penetrating/mortality , Young Adult
7.
Health Technol Assess ; 16(13): iii-xii, 1-54, 2012.
Article in English | MEDLINE | ID: mdl-22417901

ABSTRACT

BACKGROUND: Tranexamic acid (TXA) has been shown to reduce blood loss in surgical patients and the risk of death in patients with traumatic bleeding, with no apparent increase in vascular occlusive events. These findings raise the possibility that it might also be effective in traumatic brain injury (TBI). OBJECTIVE: The Clinical Randomisation of an Antifibrinolytic in Significant Haemorrhage Intracranial Bleeding Study (CRASH-2 IBS) was conducted to quantify the effect of an early short course of TXA on intracranial haemorrhage and new focal cerebral ischaemic lesions in patients with TBI. DESIGN: CRASH-2 IBS was a prospective randomised controlled trial nested within the CRASH-2 trial. Randomisation was balanced by centre, with an allocation sequence based on a block size of eight. We used a local pack system that selected the lowest numbered treatment pack from a box containing eight numbered packs. Apart from the pack number, the treatment packs were identical. The pack number was recorded on the entry form, which was sent to the international trial co-ordinating centre in London, UK. Once the treatment pack number was recorded, the patient was included in the trial whether or not the treatment pack was opened or the allocated treatment started. All site investigators and trial co-ordinating centre staff were masked to treatment allocation. SETTING: Ten hospitals: (India) Aditya Neuroscience Centre, Sanjivani Hospital, CARE Hospital, Christian Medical College, Medical Trust Hospital, Jeevan Jyoti Hospital and (Colombia) Hospital Universitario San Vicente de Paul, Hospital Pablo Tobón Uribe, Hospital Universitario San José de Popayán and Fundación Valle del Lili. PARTICIPANTS: The trial was conducted in a subset of 270 CRASH-2 trial participants. Patients eligible for inclusion in the CRASH-2 IBS fulfilled the inclusion criteria for the CRASH-2 trial, and also had TBI [Glasgow Coma Scale score of ≤ 14 and a brain computerised tomography (CT) scan compatible with TBI]. Pregnant women and patients for whom a second brain CT scan was not possible were excluded. INTERVENTIONS: Participants were randomly allocated to receive either a loading dose of 1 g of TXA infused over 10 minutes followed by an intravenous infusion of 1 g over 8 hours or matching placebo. MAIN OUTCOME MEASURE: The primary outcome was the increase in size of intracranial haemorrhage growth between a CT scan at hospital admission and a second scan 24-48 hours later. RESULTS: One hundred and thirty-three patients were allocated to TXA and 137 to placebo, of whom information on the primary (imaging) outcome was available for 123 (92%) and 126 (92%) respectively. The analysis suggested that TXA was likely to be associated with a reduction in haemorrhage growth [adjusted difference -3.8 ml, 95% credibility interval (CrI) -11.5 ml to 3.9 ml], fewer focal ischaemic lesions [adjusted odds ratio (OR) 0.54, 95% CrI 0.20 to 1.46] and fewer deaths (adjusted OR 0.49, 95% CrI 0.22 to 1.06). CONCLUSIONS: This was the first randomised controlled study to evaluate the effect of TXA in TBI patients and it found that neither moderate benefits nor moderate harmful effects can be excluded. However, although uncertainty remains, our analyses suggest that TXA administration might improve outcome in TBI patients and provide grounds for evaluating this hypothesis in future research. TRIAL REGISTRATION: Current Controlled Trials ISRCTN86750102. SOURCE OF FUNDING: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 16, No. 13. See the HTA programme website for further project information.


Subject(s)
Anti-Arrhythmia Agents/therapeutic use , Antifibrinolytic Agents/therapeutic use , Intracranial Hemorrhage, Traumatic/drug therapy , Tranexamic Acid/therapeutic use , Adult , Female , Glasgow Coma Scale , Humans , Intracranial Hemorrhage, Traumatic/diagnostic imaging , Intracranial Hemorrhage, Traumatic/physiopathology , Male , Middle Aged , Odds Ratio , Outcome Assessment, Health Care , Prospective Studies , Radiography , Tranexamic Acid/administration & dosage , Young Adult
8.
Trials ; 7: 22, 2006 Jun 21.
Article in English | MEDLINE | ID: mdl-16790038
11.
Cochrane Database Syst Rev ; (4): CD004896, 2004 Oct 18.
Article in English | MEDLINE | ID: mdl-15495129

ABSTRACT

BACKGROUND: Uncontrolled bleeding is an important cause of death in trauma victims. Antifibrinolytic treatment has been shown to reduce blood loss following surgery and may also be effective in reducing blood loss following trauma. OBJECTIVES: To quantify the effect of antifibrinolytic drugs in reducing blood loss, transfusion requirement and mortality after acute traumatic injury. SEARCH STRATEGY: We searched the Cochrane Injuries Group's Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, PubMed, EMBASE, Science Citation Index, National Research Register, Zetoc, SIGLE, Global Health, LILACS, and Current Controlled Trials. SELECTION CRITERIA: We included all randomised controlled trials of antifibrinolytic agents (aprotinin, tranexamic acid [TXA] and epsilon-aminocaproic acid) following acute traumatic injury. DATA COLLECTION AND ANALYSIS: The titles and abstracts identified in the electronic searches were screened by two independent reviewers to identify studies that had the potential to meet the inclusion criteria. The full reports of all such studies were obtained. From the results of the screened electronic searches, bibliographic searches, and contacts with experts, two reviewers independently selected trials meeting the inclusion criteria, with any disagreements resolved by consensus. MAIN RESULTS: Two studies met the inclusion criteria. The study by Auer (1979), with 20 randomised patients, provided no useable outcome data. The study by McMichan (1982), with 77 randomised patients, was reported in four separate reports. Outcome data were reported for death, the proportion undergoing surgical intervention and the volume of blood transfused. Because of the small number of randomised participants, the estimates for each of these outcomes were highly imprecise. Data on the proportion undergoing re-operation and the proportion receiving blood transfusion were not reported. REVIEWERS' CONCLUSIONS: There is insufficient evidence from randomised controlled trials of antifibrinolytic agents in trauma to either support or refute a clinically important treatment effect. Further randomised controlled trials of antifibrinolytic agents in trauma are required.


Subject(s)
Antifibrinolytic Agents/therapeutic use , Blood Transfusion/statistics & numerical data , Hemorrhage/drug therapy , Wounds and Injuries/complications , Blood Loss, Surgical/prevention & control , Hemorrhage/etiology , Humans , Randomized Controlled Trials as Topic
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