903 resultados para Intraaortic Balloon Pump
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Inscriptions: Verso: [stamped] Photograph by Freda Leinwand. [463 West Street, Studio 229G, New York, NY 10014].
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Background
Postpartum hemorrhage is the most significant contributor to maternal mortality globally, claiming 140,000 lives annually. Postpartum hemorrhage is a leading cause of maternal death in South Africa, with the literature indicating that 80 percent of the postpartum hemorrhage deaths in South Africa are avoidable. Ghana, as of 2010, witnesses 2700 maternal deaths annually, primarily because of poor quality of care in health facilities and services being difficult to access. As per WHO recommendations, uterotonics are integral to treating postpartum hemorrhage as soon as it is diagnosed. In case of persistent bleeding or limited availability of uterotonics, the uterine balloon tamponade (UBT) can be used as a second line of defense. If both these measures are unable to counter the bleeding, providers must perform surgical interventions. Literature on the UBT, as one tool in the protocol to address postpartum hemorrhage, has shown it to have success rates ranging from 60 to 100 percent. Despite the potential to lower the number of postpartum hemorrhage deaths in South Africa and Ghana, the UBT has not been incorporated widely in South Africa and Ghana. The aim of this study is to describe the barriers involved with integrating the UBT into South Africa and Ghana’s health systems to address postpartum hemorrhage.
Methods
The study took place in multiple sites in South Africa (Cape Town, Johannesburg, Durban and Mpumalanga) and in Accra, Ghana. South Africa and Ghana were selected because postpartum hemorrhage contributes greatly to their maternal mortality numbers and there is potential in both countries to lower those rates through greater use of the UBT. A total of 25 participants were interviewed through purposive sampling, snowball sampling and participant referrals, and included various categories of stakeholders integral to the integration process of a medical device. Individual in-depth interviews were used for data collection, with interview questions being tailored to each stakeholder category. The focus of the interviews was on the protocol used to counter postpartum hemorrhage, the frequency with which the UBT is used as part of the protocol, and the process of integrating it into the South Africa and Ghana’s health systems. The data collected were coded using NVivo and analyzed using content analysis.
Results
The barriers to integration of the uterine balloon tamponade to address postpartum hemorrhage in South Africa and Ghana were evident on the political, economic and health delivery levels. The results indicated that the barriers to integration in South Africa included the low recognition of postpartum hemorrhage as a problem, the lack of clarity surrounding the role of the Medicines Control Council as a regulatory body for medical devices, and low awareness of the UBT as an intervention to control postpartum hemorrhage. The barriers in Ghana were the cash constraints experienced by the Ghana Health Services to fund medical devices, a heavy reliance on donors for funding, and the lack of consistent knowledge on processes involving clinical trials for new medical devices in Ghana.
Conclusion
Existing literature on methods to counter postpartum hemorrhage to reduce maternal mortality has focused on and emphasized the efficacy of the UBT. Despite overwhelming evidence supporting the use of the UBT, many health systems across the world, particularly low-income countries, do not have access to the device owing to numerous barriers in integrating the device into obstetric care. This study illustrates the need to focus on incorporating the UBT into health systems for greater availability to health workers and its use as standard of care. Ultimately, this study can be used as a stepping-stone for more research on this subject, providing evidence to influence policymakers to integrate the UBT into their protocols for postpartum hemorrhage response.
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BACKGROUND: Observational studies evaluating the possible interaction between proton pump inhibitors (PPIs) and clopidogrel have shown mixed results. We conducted a systematic review comparing the safety of individual PPIs in patients with coronary artery disease taking clopidogrel. METHODS AND RESULTS: Studies performed from January 1995 to December 2013 were screened for inclusion. Data were extracted, and study quality was graded for 34 potential studies. For those studies in which follow-up period, outcomes, and multivariable adjustment were comparable, meta-analysis was performed.The adjusted odds or hazard ratios for the composite of cardiovascular or all-cause death, myocardial infarction, and stroke at 1 year were reported in 6 observational studies with data on individual PPIs. Random-effects meta-analyses of the 6 studies revealed an increased risk for adverse cardiovascular events for those taking pantoprazole (hazard ratio 1.38; 95% CI 1.12-1.70), lansoprazole (hazard ratio 1.29; 95% CI 1.09-1.52), or esomeprazole (hazard ratio 1.27; 95% CI 1.02-1.58) compared with patients on no PPI. This association was not significant for omeprazole (hazard ratio 1.16; 95% CI 0.93-1.44). Sensitivity analyses for the coronary artery disease population (acute coronary syndrome versus mixed) and exclusion of a single study due to heterogeneity of reported results did not have significant influence on the effect estimates for any PPIs. CONCLUSIONS: Several frequently used PPIs previously thought to be safe for concomitant use with clopidogrel were associated with greater risk of adverse cardiovascular events. Although the data are observational, they highlight the need for randomized controlled trials to evaluate the safety of concomitant PPI and clopidogrel use in patients with coronary artery disease.
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This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. This image is made available for non-commercial or educational use only.
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Resistance-Nodulation-Division (RND) efflux pumps are responsible for multidrug resistance in Pseudomonas aeruginosa. In this study, we demonstrate that CpxR, previously identified as a regulator of the cell envelope stress response in Escherichia coli, is directly involved in activation of expression of RND efflux pump MexAB-OprM in P. aeruginosa. A conserved CpxR binding site was identified upstream of the mexA promoter in all genome-sequenced P. aeruginosa strains. CpxR is required to enhance mexAB-oprM expression and drug resistance, in the absence of repressor MexR, in P. aeruginosa strains PA14. As defective mexR is a genetic trait associated with the clinical emergence of nalB-type multidrug resistance in P. aeruginosa during antibiotic treatment, we investigated the involvement of CpxR in regulating multidrug resistance among resistant isolates generated in the laboratory via antibiotic treatment and collected in clinical settings. CpxR is required to activate expression of mexAB-oprM and enhances drug resistance, in the absence or presence of MexR, in ofloxacin-cefsulodin-resistant isolates generated in the laboratory. Furthermore, CpxR was also important in the mexR-defective clinical isolates. The newly identified regulatory linkage between CpxR and the MexAB-OprM efflux pump highlights the presence of a complex regulatory network modulating multidrug resistance in P. aeruginosa.
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The incidence of anastomotic stricture following colorectal surgery has increased in recent years. This complication is observed in 2-5% of all operated patients and is probably due to the greater number of low anastomoses performed with surgical staplers. We observed 31 patients with postoperative stricture, arising from one to nine months post-surgery. All patients had been treated for colorectal cancer and underwent endoscopy either during routine follow-up or for symptoms of stenosis. In 16 patients (group A) the stricture diameter was less than 4 mm and the patients had symptoms attributable to partial bowel obstruction. In the remaining 15 patients (group B), who had difficult bowel movements, the stricture diameter ranged from 4 to 8 mm. All patients were treated with endoscopic dilation using achalasia balloons. The results were considered good when the post-dilation anastomosis diameter achieved was at least 13 mm, fair when it was 9-12 mm and poor when it was less than 9 mm. The short term results (3 weeks) were good in 27 patients (87.2%), fair in 3 patients (9.6%), and poor in 1 patient (3.2%). After several unsuccessful dilations, the latter was treated by surgery. Follow-up at 3-4 months of the remaining 30 patients revealed good results in 20 (66.6%), fair in 6 (20%), and poor in 4 (13.3%). In 1 of these 4 patients, cancer recurrence was observed and a new surgical resection was performed. In 2 patients a self–expandable metal stent was inserted for 4-6 weeks, with satisfactory results. In 1 patient a biodegradable polydioxanone stent was inserted with good results after 6 months. Follow-up at 3-4 months showed good results in 25 patients. After 38 months, cancer recurrence in the area of the anastomosis was observed in 1 patient, who was treated surgically. Endoscopic dilatation should be considered the first therapeutic approach in case of anastomotic strictures, as it is immediately effective, repeatable, and does not preclude surgery if this should become necessary. .
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In the last years the need to develop more environmentally friendly and efficient cars as led to the development of several technologies to improve the performance of internal combustion engines, a large part of the innovations are focused in the auxiliary systems of the engine, including, the oil pump, this is an element of great importance in the dynamics of the engine as well a considerable energy consumer. Most solutions for oil pumps to this day are fixed displacement, for medium and high speeds, the pump flow rate is higher than the needs of the engine, this excess flow leads to the need for recirculation of the fluid which represents a waste of energy. Recently, technological advances in this area have led to the creation of variable displacement oil pumps, these have become a 'must have' due to the numerous advantages they bring, although the working principle of vane or piston pumps is relatively well known, the application of this technology for the automotive industry is new and brings new challenges. The focus of this dissertation is to develop a new concept of variable displacement system for automotive oil pumps. The main objective is to obtain a concept that is totally adaptable to existing solutions on the market (engines), both dimensionally as in performance specifications, having at the same time an innovative mechanical system for obtaining variable displacement. The developed design is a vane pump with variable displacement going in line with existing commercial solutions, however, the variation of the eccentricity commonly used to provide an variable displacement delivery is not used, the variable displacement is achieved without varying the eccentricity of the system but with a variation of the length of the pumping chamber. The principle of operation of the pump is different to existing solutions while maintaining the ability to integrate standard parts such as control valves and mechanical safety valves, the pump is compatible with commercial solutions in terms of interfaces for connection between engine systems and pump. A concept prototype of the product was obtained in order to better evaluate the validity of the concept. The developed concept represents an innovation in oil pumps design, being unique in its mechanical system for variable displacement delivery.
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Life Cycle Climate Performance (LCCP) is an evaluation method by which heating, ventilation, air conditioning and refrigeration systems can be evaluated for their global warming impact over the course of their complete life cycle. LCCP is more inclusive than previous metrics such as Total Equivalent Warming Impact. It is calculated as the sum of direct and indirect emissions generated over the lifetime of the system “from cradle to grave”. Direct emissions include all effects from the release of refrigerants into the atmosphere during the lifetime of the system. This includes annual leakage and losses during the disposal of the unit. The indirect emissions include emissions from the energy consumption during manufacturing process, lifetime operation, and disposal of the system. This thesis proposes a standardized approach to the use of LCCP and traceable data sources for all aspects of the calculation. An equation is proposed that unifies the efforts of previous researchers. Data sources are recommended for average values for all LCCP inputs. A residential heat pump sample problem is presented illustrating the methodology. The heat pump is evaluated at five U.S. locations in different climate zones. An excel tool was developed for residential heat pumps using the proposed method. The primary factor in the LCCP calculation is the energy consumption of the system. The effects of advanced vapor compression cycles are then investigated for heat pump applications. Advanced cycle options attempt to reduce the energy consumption in various ways. There are three categories of advanced cycle options: subcooling cycles, expansion loss recovery cycles and multi-stage cycles. The cycles selected for research are the suction line heat exchanger cycle, the expander cycle, the ejector cycle, and the vapor injection cycle. The cycles are modeled using Engineering Equation Solver and the results are applied to the LCCP methodology. The expander cycle, ejector cycle and vapor injection cycle are effective in reducing LCCP of a residential heat pump by 5.6%, 8.2% and 10.5%, respectively in Phoenix, AZ. The advanced cycles are evaluated with the use of low GWP refrigerants and are capable of reducing the LCCP of a residential heat by 13.7%, 16.3% and 18.6% using a refrigerant with a GWP of 10. To meet the U.S. Department of Energy’s goal of reducing residential energy use by 40% by 2025 with a proportional reduction in all other categories of residential energy consumption, a reduction in the energy consumption of a residential heat pump of 34.8% with a refrigerant GWP of 10 for Phoenix, AZ is necessary. A combination of advanced cycle, control options and low GWP refrigerants are necessary to meet this goal.
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Campylobacter is a major cause of acute bacterial gastroenteritis worldwide, with the highest number of infections being attributed to Campylobacter jejuni. C. jejuni is a Gram negative, spiral, motile bacterium that belongs to the campylobacterales order and is related to both Helicobacter spp. and Wolinella sp.. It has long been established that proton pump inhibitors (PPIs) and other benzimidazole derivatives display anti-Helicobacter activity in vitro. PPIs have in the past been shown to affect Helicobacter pylori growth, survival, motility, morphology, adhesion/invasion potential and susceptibility to conventional antibiotics. PPIs are highly effective drugs that are well tolerated, safe for prolonged daily use and are therefore in high demand. Both the PPIs omeprazole and lansoprazole featured in the top ten drugs prescribed in England in 2014. In 2014 Campylobacter was also the most commonly diagnosed gastrointestinal infection in Scotland, in England and Wales and also in Europe. It has previously been generally accepted that patients who are being treated with PPIs are more susceptible to enteric infections such as Campylobacter than people not taking PPIs. The effect of PPI exposure on H. pylori has been investigated rigorously in the past. A single previous study has hinted that PPIs may also be capable of affecting the related organism C. jejuni,but investigations have been extremely limited in comparison to those investigating the effect of PPIs on H. pylori. This study has investigated the in vitro effects of direct contact with PPIs on the biology ofC. jejuni. Exposure to the PPI pantoprazole was found to affect C. jejuni growth/survival, motility, morphology, biofilm formation, invasion potential and susceptibility to some conventional antibiotics. Microarray studies showed that the cmeA and Cj0561c genes were significantly up-regulated in response to pantoprazole exposure and a CmeABC deficient mutant was found to be significantly more susceptible to killing by pantoprazole than was the parent strain. Proteomic analysis indicated that the oxidative stress response of C. jejuni was induced following exposure to sub-lethal concentrations of pantoprazole. C. jejuni gene expression was assessed using qRT-PCR and the genes encoding for thiol peroxidase and GroEL co-chaperonin (both involved in the C. jejuni oxidative stress response) were found to be around four times higher in response to exposure to sub-lethal concentrations of pantoprazole. Experiments using the oxidative stress inhibitors thiourea (a hydroxyl radical quencher) and bipyridyl (a ferrous iron chelator) showed that killing by pantoprazole was not mediated by hydroxyl radical production.
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Introduction: In the last few years a significant number of papers have related the use of proton-pump inhibitors (PPIs) to potential serious adverse effects that have resulted in social unrest. Objective: The goal of this paper was to provide a literature review for the development of an institutional position statement by Sociedad Española de Patología Digestiva (SEPD) regarding the safety of long-term PPI use. Material and methods: A comprehensive review of the literature was performed to draw conclusions based on a critical assessment of the following: a) current PPI indications; b) vitamin B12 deficiency and neurological disorders; c) magnesium deficiency; d) bone fractures; e) enteric infection and pneumonia; f) interactions with thienopyridine derivatives; e) complications in cirrhotic patients. Results: Current PPI indications have remained unchanged for years now, and are well established. A general screening of vitamin B12 levels is not recommended for all patients on a PPI; however, it does seem necessary that magnesium levels be measured at therapy onset, and then monitored in subjects on other drugs that may induce hypomagnesemia. A higher risk for bone fractures is present, even though causality cannot be concluded for this association. The association between PPIs and infection with Clostridium difficile is mild to moderate, and the risk for pneumonia is low. In patients with cardiovascular risk receiving thienopyridines derivatives it is prudent to adequately consider gastrointestinal and cardiovascular risks, given the absence of definitive evidence regardin potential drug-drug interactions; if gastrointestinal risk is found to be moderate or high, effective prevention should be in place with a PPI. PPIs should be cautiously indicated in patients with decompensated cirrhosis. Conclusions: PPIs are safe drugs whose benefits outweigh their potential side effects both short-term and long-term, provided their indication, dosage, and duration are appropriate.
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Proton-pump inhibitors (PPIs) are one of the most active ingredients prescribed in Spain. In recent decades there has been an overuse of these drugs in both outpatient clinics and hospitals that has lead to a significant increase in healthcare spending and to an increase in the risk of possible side effects. It is important for health professionals to know the accepted indications and the correct doses for the use of these drugs. On the market there are different types of PPI: omeprazole, pantoprazole, lansoprazole, rabeprazole and esomeprazole. Omeprazole is the oldest and most used PPI, being also the cheapest. Although there are no important differences between PPIs in curing diseases, esomeprazole, a new-generation PPI, has proved to be more effective in eradicating H. pylori and in healing severe esophagitis compared to other PPIs. In recent years the use of generic drugs has spread; these drugs have the same bioavailability than the original drugs. In the case of PPIs, the few comparative studies available in the literature between original and generic drugs have shown no significant differences in clinical efficacy.
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Streptococcus suis is an emerging zoonotic agent responsible for high-mortality outbreaks among the human population in China. In this species, the ABC transporter SatAB mediates fluoroquinolone resistance when overexpressed. Here, we describe and characterize satR, an open reading frame (ORF) encoding a MarR superfamily regulator that acts as a repressor of satAB. satR is cotranscribed with satAB, and its interruption entails the overexpression of the pump, leading to a clinically relevant increase in resistance to fluoroquinolones.
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Historically, domestic tasks such as preparing food and washing and drying clothes and dishes were done by hand. In a modern home many of these chores are taken care of by machines such as washing machines, dishwashers and tumble dryers. When the first such machines came on the market customers were happy that they worked at all! Today, the costs of electricity and customers’ environmental awareness are high, so features such as low electricity, water and detergent use strongly influence which household machine the customer will buy. One way to achieve lower electricity usage for the tumble dryer and the dishwasher is to add a heat pump system. The function of a heat pump system is to extract heat from a lower temperature source (heat source) and reject it to a higher temperature sink (heat sink) at a higher temperature level. Heat pump systems have been used for a long time in refrigerators and freezers, and that industry has driven the development of small, high quality, low price heat pump components. The low price of good quality heat pump components, along with an increased willingness to pay extra for lower electricity usage and environmental impact, make it possible to introduce heat pump systems in other household products. However, there is a high risk of failure with new features. A number of household manufacturers no longer exist because they introduced poorly implemented new features, which resulted in low quality and product performance. A manufacturer must predict whether the future value of a feature is high enough for the customer chain to pay for it. The challenge for the manufacturer is to develop and produce a high-performance heat pump feature in a household product with high quality, predict future willingness to pay for it, and launch it at the right moment in order to succeed. Tumble dryers with heat pump systems have been on the market since 2000. Paper I reports on the development of a transient simulation model of a commercial heat pump tumble dryer. The measured and simulated results were compared with good similarity. The influence of the size of the compressor and the condenser was investigated using the validated simulation model. The results from the simulation model show that increasing the cylinder volume of the compressor by 50% decreases the drying time by 14% without using more electricity. Paper II is a concept study of adding a heat pump system to a dishwasher in order to decrease the total electricity usage. The dishwasher, dishware and water are heated by the condenser, and the evaporator absorbs the heat from a water tank. The majority of the heat transfer to the evaporator occurs when ice is generated in the water tank. An experimental setup and a transient simulation model of a heat pump dishwasher were developed. The simulation results show a 24% reduction in electricity use compared to a conventional dishwasher heated with an electric element. The simulation model was based on an experimental setup that was not optimised. During the study it became apparent that it is possible to decrease electricity usage even more with the next experimental setup.