Recepcion de balastos para lamparas de vapor de mercurio

La gran utilización de artefactos y equipos con lámparas de vapor de mercurio, destinados a la iluminación pública, originó la necesidad de evaluar las características del balasto, accesorio fundamental de este tipo de fuentes de luz. Los ensayos que señala el autor de este trabajo son aptos, por la rapidez de ejecución y representatividad, para facilitar las tareas de recepción y control. A través de los mismos se pueden obtener valores comparativos, cuando se utiliza una lámpara de referencia, y valores uniformes y reproducibles en el caso de utilizar, además, el balasto patrón correspondiente.This paper details some of the most important testing procedures in ballast for mercury gas-discharge lamps. The more important conditions affecting lamps and ballast testing are described. This procedure was selected for his celerity and for his représentâtivi- ty for the reception and control of the lamps ballasts. Comparative values can be obtained using a reference lamp, and for uniform and reproductible values the use of a reference ballast in necesary

The Medical Liability Exemption: A Path to Affordable Pharmaceuticals

Patent monopolies are tolerated because we believe they promote progress that benefits society. What should be done when these monopolies actually increase human suffering? Drug prices in America are fifty to eighty percent higher than the rest of the world, meaning many cannot afford drugs that will improve or even save their lives. When striking a balance between the interests of the patent holder and that of the public, it is important to bear in mind that the rewards granted to patentees are secondary to the public benefit derived from their labors. The ideal solution would come from Congress creating a need-based exception to drug patent infringement, but this is unlikely to occur. An infrequently used statutory exemption, found in Section 287(c) of the Patent Act, precludes liability when a physician infringes a medical process patent. With the advances in 3D printing, doctors will soon be able to print drugs for their patients. The courts could interpret 287(c) to protect physicians from patent liability for printing drugs when provided to patients demonstrating financial hardship. When faced with new technology, the courts have been creative in interpreting the intellectual property statutes in order to reach a just and equitable resolution. The public need for affordable drugs should spur the courts to such creativity when addressing the issue of 3D drug printing

Development of homogeneous expression of resistance in methicillin-resistant Staphylococcus aureus clinical strains is functionally associated with a β-lactam-mediated SOS response

Objectives: One of the main characteristics of methicillin-resistant Staphylococcus aureus (MRSA) from both hospitals and community is their heterogeneous expression of resistance. Recently, we reported new heterogeneous MRSA isolates phenotypically susceptible to oxacillin despite being mecA positive. These low-level mecA-mediated resistance MRSA strains are very heterogeneous in expression (HeR) and are likely to be clinically relevant since exposure of such isolates to b-lactams can result in high-level homotypic resistance (HoR). We hypothesized that HeR to HoR selection in these clinically relevant strains may be determined by the pre-existence of a hypermutable population that favours its selection in the presence of oxacillin. Methods: Using established procedures, SA13011 HeR to HoR selection was performed by using subinhibitory concentrations of oxacillin and examined for mutability. Real-time RT-PCR and transcriptional profiling by DNA microarray were used to compare gene expression between both populations and related genetically modified SA13011 strain. Results: We found that HeR/HoR selection by oxacillin was associated with increased mutation rate and oxacillin-mediated SOS response. We determined increased expression of both mecA and SOS response lexA/recA regulators. Mutational inactivation of lexA repressor resulted in a significant decrease in both mutation rate and oxacillin resistance in the HoR cells. Complementation of the lexA mutant strain restored oxacillin resistance to the high levels observed in the corresponding HoR wild-type strain. Conclusions: The present results support the notion that SOS response is mechanistically involved in generating mutations that, in addition to mecA induction, allow the selection of a highly oxacillin-resistant population.Fil: Cuirolo, Arabela Ximena. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Plata, Konrad. University of Virginia; Estados UnidosFil: Rosato, Adriana E.. University of Virginia; Estados Unido

Pharmacological effects of raas blockade in ischemic nephropathy

Background: The management of ischemic nephropathy due to atherosclerotic renal artery stenosis has become increasingly conservative in the modern era, with current guidelines recommending optimized medical therapy as the initial step. The doubts raised by the recently published trials of revascularization strategies have led to a renewed focus on pharmacological strategies promoting blood pressure control and renal protection. It is essential to further elucidate the pathophysiological mechanisms underlying hypoperfusion induced renal microvascular dysfunction with subsequent tissue injury and fibrogenesis. The role of renin angiotensin aldosterone system as a mediator of the main pathophysiological consequences of ischemic nephropathy is well known. However, more recent experimental evidence on the adrenergic system and intrarenal tubular feedback mechanisms has stimulated new interest towards a multi-target therapeutic approach. Methods: This review focuses on the pharmacology of the principle therapeutic drug classes currently used in the treatment of atherosclerotic renal artery stenosis with an analysis of their metabolic aspects and use in clinical practice based on evidence from clinical trials. Results and Conclusions: An optimal pharmacologic approach is crucial for a successful prevention of renal injury and cardiovascular events in this high-risk population. Antihypertensive treatment should include renin angiotensin aldosterone system blockade medication not only for their antihypertensive properties, but especially for those cardio and renoprotectiv

Immune response impairs learning in free-flying bumble-bees

Parasites can influence different host behaviours including foraging, mate choice and predator avoidance. Several recent papers have shown reduced learning abilities in infected insects. However, it is difficult to separate the effects of the immune response from the direct effects of the parasite. Using a free-flying learning paradigm, this paper shows that learning performance is impaired in bumble-bees (Bombus terrestris) that are not infected but whose immune system is stimulated non-pathogenically. This demonstrates that before it is assumed that a parasite has a direct effect on a host's behaviour, the effect of the immune response stimulated by the parasite must first be quantified

Development of multidrug resistance in staphylococci driven by efflux

[P282]Aim: To study the efflux driven response of two major staphylococcal pathogens, S. aureus and S. epi-dermidis to the challenge by non-antibiotic drugs. Methods: We adapted three reference strains to ethidium bromide (EtBr), a broad substrate of bacte-rial efflux pumps. The parental strains, S. aureus ATCC25923, S. epidermidis ATCC12228 and S. epider-midis RP62A were cultured in varying concentrations of EtBr, to obtain their EtBr-adapted derivatives; ATCC25923_EtBr; ATCC12228_EtBr and RP62A_EtBr. Susceptibility of parental and adapted strains to 10 antibiotics and 6 biocides was evaluated by microdilution MIC determination with or without efflux inhibitors. Efflux activity was established by fluorometric assays and the relative expression of the genes coding for the main efflux pumps (EPs) of each species quantified by RT-PCR.Results: For each strain tested, exposure to EtBr resulted in the development of a multidrug resistance (MDR) phenotype, which included resistance to fluoroquinolones and decreased susceptibility to bio-cides, including cetrimide, benzalkonium chloride and tetraphenylphosphonium bromide. Efflux inhib-itors such as verapamil reduced these resistance levels. The EtBr-adapted cultures showed increased efflux activity, which was accompanied by over-expression of distinct EP genes, in a temporal pattern. Conclusion: These results show that both S. aureus and S. epidermidis have the potential to develop efflux driven MDR phenotypes when exposed to a non-antibiotic substrate of multidrug EPs, which can be mediated by distinct efflux pumps, depending on the drug and the bacterial genetic background.publishe

Community-linked maternal death review (CLMDR) to measure and prevent maternal mortality: a pilot study in rural Malawi.

In Malawi, maternal mortality remains high. Existing maternal death reviews fail to adequately review most deaths, or capture those that occur outside the health system. We assessed the value of community involvement to improve capture and response to community maternal deaths

Does Intraoperative Radiation Therapy Improve Local Tumor Control in Patients Undergoing Pancreaticoduodenectomy for Pancreatic Adenocarcinoma? A Propensity Score Analysis

Background: Locoregional recurrence (LRR) is an important factor after pancreaticoduodenectomy (PD) for pancreatic cancer. IORT administered to the resection bed may improve local tumor control. Methods: We performed a retrospective analysis of patients who underwent PD at Thomas Jefferson University Hospital (TJUH) between 1995 and 2005 to identify patients who underwent resection with and without intraoperative radiation therapy (IORT). Data collected included age, gender, complications, margin status, stage, survival, and recurrence. Unadjusted analyses of the IORT and non-IORT groups were performed using Fisher’s chi-square method for discrete variables and Wilcoxon Rank Sum test for continuous variables. To account for biases in patient selection for IORT, a propensity score was calculated for each patient and adjusted statistical analyses were performed for survival and recurrence outcomes. Results: Between January 1995 and November 2005, 122 patients underwent PD for perimpullary tumors, including 99 pancreatic cancers. Of this group, 37 patients were treated with IORT, and there was adequate follow-up information for a group of 46 patients who underwent PD without IORT. The IORT group contained a higher percentage of Stage IIB or higher tumors (65%) than in the non-IORT group (39.1%), though differences in stage did not reach significance (p = 0.16). There was a non-significant decrease in the rate of LRR in patients who had IORT (39% non-IORT vs. 23% IORT, p = 0.19). The median survival time of patients who received IORT was 19.2 months, which was not significantly different than patients managed without IORT, 21.0 months (p=0.78). In the propensity analyses, IORT did not significantly influence survival or recurrence after PD. Conclusions: IORT can be safely added to management approaches for resectable pancreatic cancer, with acceptable morbidity and mortality. IORT did not improve loco-regional control and did not alter survival for patients with resected pancreatic cancer. IORT is an optional component of adjuvant chemoradiation for pancreatic cancer. In the future, IORT may be combined with novel therapeutic agents in the setting of a clinical trial in order to attempt to improve outcomes for patients with pancreatic cancer. Annals of Surgical Oncology, Volume 16, Edition 8, August, 2009, pages 2116-22, “Does intraoperative radiation therapy improve local tumor control in patients undergoing pancreaticoduodenectomy for pancreatic adenocarcinoma? A propensity score analysis”. Authors: Showalter TN, Rao AS, Anné PR, Rosato FE, Rosato EL, Andrel J, Hyslop T, Xu X, Berger AC