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The Andean Condor (Vultur gryphus) in Ecuador is classified as Critically Endangered. Before 2015, standardized and systematic estimates of geographic distribution, population size and structure were not available for this species, hampering the assessment of its current status and hindering the design and implementation of effective conservation actions. In this study, we performed the first quantitative assessment of geographic distribution, population size and population viability of Andean Condor in Ecuador. We used a methodological approach that included an ecological niche model to study geographic distribution, a simultaneous survey of 70 roosting sites to estimate population size and a population viability analysis (PVA) for the next 100 years. Geographic distribution in the form of extent of occurrence was 49 725 km2. During a two-day census, 93 Andean Condors were recorded and a population of 94 to 102 individuals was estimated. In this population, adult-to-immature ratio was 1:0.5. In the modeled PVA scenarios, the probability of extinction, mean time to extinction and minimum population size varied from zero to 100%, 63 years and 193 individuals, respectively. Habitat loss is the greatest threat to the conservation of Andean Condor populations in Ecuador. Population size reduction in scenarios that included habitat loss began within the first 15 years of this threat. Population reinforcement had no effects on the recovery of Andean Condor populations given the current status of the species in Ecuador. The population size estimate presented in this study is the lower than those reported previously in other countries where the species occur. The inferences derived from the population viability analysis have implications for Condor management in Ecuador. This study highlights the need to redirect efforts from captive breeding and population reinforcement to habitat conservation.

Septin complexes display remarkable plasticity in subunit composition, yet how a new subunit assembled into higher-order structures confers different functions is not fully understood. Here, this question is addressed in budding yeast, where during meiosis Spr3 and Spr28 replace the mitotic septin subunits Cdc12 and Cdc11 (and Shs1), respectively. In vitro, the sole stable complex that contains both meiosis-specific septins is a linear Spr28-Spr3-Cdc3-Cdc10-Cdc10-Cdc3-Spr3-Spr28 hetero-octamer. Only coexpressed Spr3 and Spr28 colocalize with Cdc3 and Cdc10 in mitotic cells, indicating that incorporation requires a Spr28-Spr3 protomer. Unlike their mitotic counterparts, Spr28-Spr3-capped rods are unable to form higher-order structures in solution but assemble to form long paired filaments on lipid monolayers containing phosphatidylinositol-4,5-bisphosphate, mimicking presence of this phosphoinositide in the prospore membrane. Spr28 and Spr3 fail to rescue the lethality of a cdc11Δ cdc12Δ mutant, and Cdc11 and Cdc12 fail to restore sporulation proficiency to spr3Δ/spr3Δ spr28Δ/spr28Δ diploids. Thus, specific meiotic and mitotic subunits endow septin complexes with functionally distinct properties., (© 2016 Garcia et al.)

Primary cilia interpret vertebrate Hedgehog (Hh) signals. Why cilia are essential for signaling is unclear. One possibility is that some forms of signaling require a distinct membrane lipid composition, found at cilia. We found that the ciliary membrane contains a particular phosphoinositide, PI(4)P, whereas a different phosphoinositide, PI(4,5)P2, is restricted to the membrane of the ciliary base. This distribution is created by Inpp5e, a ciliary phosphoinositide 5-phosphatase. Without Inpp5e, ciliary PI(4,5)P2 levels are elevated and Hh signaling is disrupted. Inpp5e limits the ciliary levels of inhibitors of Hh signaling, including Gpr161 and the PI(4,5)P2-binding protein Tulp3. Increasing ciliary PI(4,5)P2 levels or conferring the ability to bind PI(4)P on Tulp3 increases the ciliary localization of Tulp3. Lowering Tulp3 in cells lacking Inpp5e reduces ciliary Gpr161 levels and restores Hh signaling. Therefore, Inpp5e regulates ciliary membrane phosphoinositide composition, and Tulp3 reads out ciliary phosphoinositides to control ciliary protein localization, enabling Hh signaling., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: Treatment-related mortality and abandonment of therapy are major barriers to successful treatment of childhood acute lymphoblastic leukemia (ALL) in the developing world., Procedure: A collaboration was undertaken between Instituto Nacional de Cancerologia (Bogota, Colombia), which serves a poor patient population in an upper-middle income country, and Dana-Farber/Boston Children's Cancer and Blood Disorders Center (Boston, USA). Several interventions aimed at reducing toxic deaths and abandonment were implemented, including a reduced-intensity treatment regimen and a psychosocial effort targeting abandonment. We performed a cohort study to assess impact., Results: The Study Population comprised 99 children with ALL diagnosed between 2007 and 2010, and the Historic Cohort comprised 181 children treated prior to the study interventions (1995-2004). Significant improvements were achieved in the rate of deaths in complete remission (13% to 3%; P = 0.005), abandonment (32% to 9%; P < 0.001), and event-free survival with abandonment considered an event (47% to 65% at 2 years; P = 0.016). However, relapse rate did not improve. Medically unnecessary treatment delays were common, and landmark analysis revealed that initiating the PIII phase of therapy ≥4 weeks delayed predicted markedly inferior disease-free survival (P = 0.016). Conversely, patients who received therapy without excessive delays had outcomes approaching those achieved in high-income countries., Conclusions: Implementation of a twinning program was followed by reductions in abandonment and toxic deaths, but relapse rate did not improve. Inappropriate treatment delays were common and strongly predicted treatment failure. These findings highlight the importance of adherence to treatment schedule for effective therapy of ALL., (© 2015 Wiley Periodicals, Inc.)

The effects of the direct interaction between hybridization and speciation-two major contrasting evolutionary processes--are poorly understood. We present here the evolutionary history of the Galápagos marine iguana (Amblyrhynchus cristatus) and reveal a case of incipient within--island speciation, which is paralleled by between-island hybridization. In-depth genome-wide analyses suggest that Amblyrhynchus diverged from its sister group, the Galápagos land iguanas, around 4.5 million years ago (Ma), but divergence among extant populations is exceedingly young (less than 50,000 years). Despite Amblyrhynchus appearing as a single long-branch species phylogenetically, we find strong population structure between islands, and one case of incipient speciation of sister lineages within the same island--ostensibly initiated by volcanic events. Hybridization between both lineages is exceedingly rare, yet frequent hybridization with migrants from nearby islands is evident. The contemporary snapshot provided by highly variable markers indicates that speciation events may have occurred throughout the evolutionary history of marine iguanas, though these events are not visible in the deeper phylogenetic trees. We hypothesize that the observed interplay of speciation and hybridization might be a mechanism by which local adaptations, generated by incipient speciation, can be absorbed into a common gene pool, thereby enhancing the evolutionary potential of the species as a whole., (© 2015 The Author(s) Published by the Royal Society. All rights reserved.)

Central pontine myelinolysis (CPM) is classically attributed to overly rapid correction of profound hyponatremia. However, there are case reports of this disease in the setting of normal serum sodium or minimal hyponatremia. These cases have been hypothesized to be secondary to other metabolic disturbances such as hyperglycemia or hypophosphatemia. Eunatremic CPM has also been described in patients with advanced acquired immune deficiency syndrome (AIDS). The mortality risk in this special population is significantly higher than those with hyponatremia-associated CPM, but the mechanisms are unclear. We discuss a case of a man with AIDS who developed CPM with minimal hyponatremia and no other metabolic disturbances. Common variables within this population, such as hypoalbuminemia and lymphoma, are discussed as potential factors contributing to the pathophysiology. Reporting these atypical cases is crucial to our understanding of how to prevent future cases.

The septins are a family of GTP-binding proteins that form cytoskeletal filaments. Septins are highly conserved and evolutionarily ancient but are absent from land plants. The synthetic plant cytokinin forchlorfenuron (FCF) was shown previously to inhibit budding yeast cell division and induce ectopic septin structures (M. Iwase, S. Okada, T. Oguchi, and A. Toh-e, Genes Genet. Syst. 79:199-206, 2004, http://dx.doi.org/10.1266/ggs.79.199). Subsequent studies in a wide range of eukaryotes have concluded that FCF exclusively inhibits septin function, yet the mechanism of FCF action in nonplant cells remains poorly understood. Here, we report that the cellular effects of FCF are far more complex than previously described. The reported growth arrest of budding yeast cells treated with 1 mM FCF partly reflects sensitization caused by a bud4 mutation present in the W303 strain background. In wild-type (BUD4(+)) budding yeast, growth was inhibited at FCF concentrations that had no detectable effect on septin structure or function. Moreover, FCF severely inhibited the proliferation of fission yeast cells, in which septin function is nonessential. FCF induced fragmentation of budding yeast mitochondrial reticula and the loss of mitochondrial membrane potential. Mitochondria also fragmented in cultured mammalian cells treated with concentrations of FCF that previously were assumed to target septins only. Finally, FCF potently inhibited ciliation and motility and induced mitochondrial disorganization in Tetrahymena thermophila without apparent alterations in septin structure. None of these effects was consistent with the inhibition of septin function. Our findings point to nonseptin targets as major concerns when using FCF., (Copyright © 2014, American Society for Microbiology. All Rights Reserved.)

Objective: This study sought to assess whether the association between statin use and bone mineral density (BMD) and bone turnover markers is modulated by serum 25-hydroxyvitamin D (25OHD) levels in postmenopausal women. Design, Participants, and Settings: Approximately 1422 postmenopausal women were recruited from the Camargo Cohort after excluding those with any known medical disorder or drug that might affect bone metabolism. Participants were categorized into four groups: 25OHD levels of 20 ng/mL or less and not taking statins (group 1; n = 492); 25OHD levels greater than 20 ng/mL and on statins (group 2; n = 143); 25OHD levels of 20 ng/mL or less and using statins (group 3; n = 112); and 2OHD levels greater than 20 ng/mL and non-statin use (group 4; n = 675). Multivariate analyses were performed to compare BMD and bone turnover markers between groups., Results: Women in group 2 had an adjusted femoral neck and total hip BMD higher than women in group 1 (P < .0001 and P = .003, respectively). A trend toward a significant difference was observed regarding lumbar BMD (P = .08). Serum aminoterminal propeptide of type 1 collagen and C-terminal telopeptide of type 1 collagen levels were lower in group 2 than in group 1, in crude and adjusted models, although only serum C-terminal telopeptide of type 1 collagen difference was significant (P = .009)., Conclusions: Women on statins and serum 25OHD levels above 20 ng/mL have greater BMD and less bone resorption than those without either of the factors. Differences, however, are not significant in women with only one of them. Vitamin D and statins seem to interact positively in their effects on bone metabolism.

Objectives: The aim of this study was to assess the possible mismatch of obstetrical skills between the training offered in Ecuadorian medical schools and the tasks required for compulsory rural service., Setting: Primary care, rural health centres in Southern Ecuador., Participants: A total of 92 recent graduated medical doctors during their compulsory rural year., Primary and Secondary Outcomes Measures: A web-based survey was developed with 21 obstetrical skills. The questionnaire was sent to all rural doctors who work in Loja province, Southern Ecuador, at the Ministry of Health (n=92)., We Measured Two Categories: 'importance of skills in rural practice' with a five-point Likert-type scale (1= strongly disagree; 5= strongly agree); and 'clerkship experience' using a nominal scale divided in five levels: level 1 (not seen, not performed) to level 5 (performed 10 times or more). Spearman's rank correlation coefficient (r) was used to observe associations., Results: A negative correlation was found in the skills: 'episiotomy and repair', 'umbilical vein catheterisation', 'speculum examination', 'evaluation of cervical dilation during active labour', 'neonatal resuscitation' and 'vacuum-assisted vaginal delivery'. For instance 'Episiotomy and repair' is important (strongly agree and agree) to 100% of respondents, but in practice, only 38.9% of rural doctors performed the task three times and 8.3% only once during the internship, similar pattern is seen in the others., Conclusions: In this study we have noted the gap between the medical needs of populations in rural areas and training provided during the clerkship experiences of physicians during their rural service year. It is imperative to ensure that rural doctors are appropriately trained and skilled in the performance of routine obstetrical duties. This will help to decrease perinatal morbidity and mortality in rural Ecuador., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

We studied 2,315 subjects (1,422 women and 893 men) from the Camargo Cohort and analyzed the differences in BMD between statin or non-statin users. We also studied effects of the type of statin, dose, pharmacokinetic properties, and length of treatment on bone mineral density (BMD). Of the subjects, 478 (21 %) were taking statins (256 women and 222 men). Overall, they had higher BMD than non-users (p < 0.0001). In adjusted multivariate models, women taking statins had higher BMD at femoral neck (p = 0.002) and total hip (p = 0.04) than non- users. No differences were found in men. Women taking simvastatin had higher increases in BMD than non-statin users at femoral neck (p = 0.02) and total hip (p = 0.009), those taking fluvastatin had lower BMD values at lumbar spine (p = 0.028), and those receiving lovastatin had higher increases at femoral neck (p = 0.006). In men, only atorvastatin was associated with higher femoral neck BMD than non-statin use (p = 0.029). Comparing with non-statin users, only women receiving lipophilic statins had greater BMD at femoral neck (p = 0.003). According to drug potency, women on high- or lower-potency agents showed higher BMD values at femoral neck than non-users (p = 0.028 and 0.022, respectively). In men, only high-potency statins were associated with higher femoral neck BMD than non-use (p = 0.021). No differences between dose or length of statin therapy were noted regarding BMD in either sex. In summary, in a large population-based cohort, women on statins had higher BMD at the hip than non-users. Overall, this increase in BMD was more evident in subjects on lipophilic or high-potency statins.

Aim: To distinguish typologies of university students in southern Chile on the basis of their level of satisfaction with life and food-related life, and to characterize them according to their eating habits inside and outside the place of residence, aspects associated with health and demographic characteristics., Materials and Methods: A structured questionnaire was applied to a non-probabilistic sample of 347 students at the Universidad de La Frontera, Temuco, Chile. The instruments for collecting information included the SWLS (Satisfaction with Life Scale), SWFL (Satisfaction with Food-related Life) and the HRQOL (Health-related Quality of Life Index). Questions were asked about eating habits inside and outside the place of residence, weight and approximate height, and variables for demographic classification., Results: Using a cluster analysis, three student typologies were distinguished, with significant differences in the SWLS and SWFL scores. The typologies differed in the number of days affected by emotional health problems, classification of their nutritional status (BMI), self-perception of their state of health, importance of food to personal well-being, place of residence during the period of studies, frequency of eating in the place of residence and frequency of meals at inconvenient times., Conclusions: The possibility of living with parents during the period of university studies is associated with better eating habits, better emotional health and self-perception of health, lower prevalence of overweight and obesity, and greater satisfaction with the life and food-related life., (Copyright AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.)

Objective: To analyze the effects of statin use on bone turnover markers (BTM), in participants from a large population-based cohort., Subjects and Methods: Cross-sectional study that included 2431 subjects (1401 women and 930 men) from the Camargo Cohort. We analyzed the differences in serum BTM between statin or non-statin users, by means of a generalized linear model, adjusted for a wide set of covariates and stratified by diabetes status. We also studied the effect of the type of statin, dose, pharmacokinetic properties, and length of treatment, on BTM., Results: Five hundred subjects (21%) were taking statins (273 women and 227 men). Overall, they had lower levels of aminoterminal propeptide of type I collagen (PINP) and C-terminal telopeptide of type I collagen (CTX) than non-users (p<0.0001). BTM levels were significantly lower in diabetic women using statins, than in female non-statin users with diabetes. In men, we found similar results, but only for CTX. All the statins users had lower levels of BTM than non-users, except subjects taking fluvastatin that showed slightly higher values. In the whole sample, no differences between dose or drug-potency were noted regarding BTM. When comparing with non-statin users, only subjects taking lipophilic statins had lower BTM levels (p<0.0001). Serum CTX levels were lower in women using statins for more than 3 vs. 1-3 years (p=0.006)., Conclusions: In a large population-based cohort, serum BTM were lower in participants taking statins than in non-users, and this effect was modulated by diabetes status. Overall, this decrease in BTM was more evident in subjects receiving the more lipophilic statins, especially when using for more than 3 years., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Background: The objective of this study is to analyze the factors that are associated with the adequacy of empirical antibiotic therapy and its impact in mortality in a large cohort of patients with extended-spectrum β-lactamase (ESBL)--producing Escherichia coli and Klebsiella spp. bacteremia., Methods: Cases of ESBL producing Enterobacteriaceae (ESBL-E) bacteremia collected from 2003 through 2008 in 19 hospitals in Spain. Statistical analysis was performed using multivariate logistic regression., Results: We analyzed 387 cases ESBL-E bloodstream infections. The main sources of bacteremia were urinary tract (55.3%), biliary tract (12.7%), intra-abdominal (8.8%) and unknown origin (9.6%). Among all the 387 episodes, E. coli was isolated from blood cultures in 343 and in 45.71% the ESBL-E was multidrug resistant. Empirical antibiotic treatment was adequate in 48.8% of the cases and the in hospital mortality was 20.9%. In a multivariate analysis adequacy was a risk factor for death [adjusted OR (95% CI): 0.39 (0.31-0.97); P = 0.04], but not in patients without severe sepsis or shock. The class of antibiotic used empirically was not associated with prognosis in adequately treated patients., Conclusion: ESBL-E bacteremia has a relatively high mortality that is partly related with a low adequacy of empirical antibiotic treatment. In selected subgroups the relevance of the adequacy of empirical therapy is limited.

Background: Little is known about the correlation between modifications in plaque composition at stent edges and the changes in vessel geometry. This study sought to evaluate, by serial greyscale intravascular ultrasound (IVUS) and Virtual Histology intravascular ultrasound (VH-IVUS), the modifications in plaque composition at the edges of drug-eluting and bare metal stents and the correlation of these findings with changes in the measurements of vessel, lumen and plaque area at those segments., Methods and Results: Single-centre, prospective and randomised (1:1) evaluation of 40 patients with acute coronary syndrome treated with bare metal (Driver; Medtronic, Santa Clara, CA, USA; n=20 patients) or drug-eluting stents (Cypher; Cordis, Miami Lakes, FL, USA; n=20 patients). IVUS and VH-IVUS assessments were done post-procedure and at nine months. Primary endpoint included the modification in vessel, lumen and plaque area and in the composition of the plaque in the mean time between the baseline and follow-up procedure. At the proximal edge of the vessel treated with the Cypher stent, a trend toward positive vessel remodelling (D=+0.6 mm², p=0.06) was observed while at the distal edge, less plaque growth (D=+0.2 mm² vs. D=+1.1 mm², p<0.001), resulted in a larger lumen area at follow-up. By VH, there was a marked reduction in the percentage of fibrotic tissue and necrotic core at the edges of both stents and a positive correlation was seen between increase in percentage of fibro-fatty component and increase in plaque area (r=0.78, p=0.01)., Conclusion: Patients treated with drug-eluting stents (DES) experienced less plaque growth, especially at the distal edge of the stents. Modifications in plaque composition, with increase in fibrofatty tissue component, may partially explain these findings.

Unlabelled: Spinal gamma-aminobutyric acid receptor type A (GABA(A)) receptor modulation with agonists and allosteric modulators evokes analgesia and antinociception. Changes in K(+)-Cl(-) cotransporter isoform 2 (KCC2) expression or function that occur after peripheral nerve injury can result in an impairment in the Cl(-) extrusion capacity of spinal dorsal horn neurons. This, in turn, alters Cl(-)-mediated hyperpolarization via GABA(A) receptor activation, contributing to allodynia or hypersensitivity associated with nerve injury or inflammation. A gap in knowledge exists concerning how this loss of spinal KCC2 activity differentially impacts the analgesic efficacy or potency of GABA(A) agonists and allosteric modulators. We utilized intrathecal drug administration in the tail flick assay to measure the analgesic effects of general GABA(A) agonists muscimol and Z-3-[(aminoiminomethyl)thio]prop-2-enoic acid (ZAPA), the ∂-subunit-preferring agonist 4,5,6,7-tetrahydroisoxazolo(5,4-c)pyridin-3-ol (THIP), and allosteric modulators of the benzodiazepine (midazolam) and neurosteroid (ganaxolone) class, alone or in the presence of K(+)-Cl(-) cotransporter isoform (KCC) blockade. Intrathecal muscimol, ZAPA, THIP midazolam, and ganaxolone all evoked significant analgesia in the tail flick test. Coadministration of either agonists or allosteric modulators with [(dihydroindenyl)oxy] alkanoic acid (DIOA) (a drug that blocks KCC2) had no effect on agonist or allosteric modulator potency. On the other hand, the analgesic efficacy of muscimol and ZAPA and the allosteric modulator ganaxolone were markedly reduced whereas THIP and midazolam were unaffected. Finally, in the spared nerve injury model, midazolam significantly reversed tactile hypersensitivity while ganaxolone had no effect. These results indicate that the KCC2-dependent Cl(-) extrusion capacity differentially regulates the analgesic efficacy of agonists and allosteric modulators at the GABA(A) receptor complex., Perspective: Our work suggests that drug discovery efforts for the treatment of chronic pain disorders should target benzodiazepine or ∂-subunit-containing sites at the GABA(A) complex., (Copyright © 2012 American Pain Society. Published by Elsevier Inc. All rights reserved.)

Septins are conserved GTP-binding proteins involved in membrane compartmentalization and remodeling. In budding yeast, five mitotic septins localize at the bud neck, where the plasma membrane is enriched in phosphatidylinositol-4,5-bisphosphate (PtdIns4,5P(2)). We previously established the subunit organization within purified yeast septin complexes and how these hetero-octamers polymerize into filaments in solution and on PtdIns4,5P(2)-containing lipid monolayers. How septin ultrastructure in vitro relates to the septin-containing filaments observed at the neck in fixed cells by thin-section electron microscopy was unclear. A morphological description of these filaments in the crowded space of the cell is challenging, given their small cross section. To examine septin organization in situ, sections of dividing yeast cells were analyzed by electron tomography of freeze-substituted cells, as well as by cryo-electron tomography. We found networks of filaments both perpendicular and parallel to the mother-bud axis that resemble septin arrays on lipid monolayers, displaying a repeat pattern that mirrors the molecular dimensions of the corresponding septin preparations in vitro. Thus these in situ structures most likely represent septin filaments. In viable mutants lacking a single septin, in situ filaments are still present, although more disordered, consistent with other evidence that the in vivo function of septins requires filament formation.

Objectives: This project aims to answer a critically important question of public policy: Does effective child support enforcement lead to a change in the incidence of abortion across the United States?, Methods: Using state-level data collected from 1978–2003 from a variety of sources, we employ fixed effects regression analysis to examine whether financial security as measured by five types of child support enforcement effectiveness impacts abortion outcomes., Results: We find that child support enforcement effectiveness decreases the incidence of abortion as measured by the abortion rate, but not the abortion ratio., Conclusions: Income transfer policies such as child support enforcement can affect certain fertility outcomes such as abortion rates across the states.

Sludge management in waste stabilization ponds (WSPs) is essential for safeguarding the system performance. Sludge accumulation patterns in WSPs are strongly influenced by the pond hydrodynamics. CFD modeling was applied to study the relation between velocity profiles and sludge deposition during 10 years of operation of the Ucubamba WSP in Cuenca (Ecuador). One tracer experiment was performed and three sludge accumulation scenarios based on bathymetric surveys were simulated. A residence time distribution (RTD) analysis illustrated the decrease of residence times due to sludge deposition. Sludge accumulation rates were calculated. The influence of flow pattern on the sludge deposition was studied, enabling better planning of future pond operation and desludging.

Septins are conserved guanosine triphosphate-binding cytoskeletal proteins involved in membrane remodeling. In budding yeast, five mitotic septins (Cdc3, Cdc10, Cdc11, Cdc12, and Shs1), which are essential for cytokinesis, transition during bud growth from a patch to a collar, which splits into two rings in cytokinesis and is disassembled before the next cell cycle. Cdc3, Cdc10, Cdc11, and Cdc12 form an apolar octameric rod with Cdc11 at each tip, which polymerizes into straight paired filaments. We show that Shs1 substitutes for Cdc11, resulting in octameric rods that do not polymerize into filaments but associate laterally, forming curved bundles that close into rings. In vivo, half of shs1Δ mutant cells exhibit incomplete collars and disrupted neck filaments. Importantly, different phosphomimetic mutations in Shs1 can either prevent ring formation or promote formation of a gauzelike meshwork. These results show that a single alternative terminal subunit is sufficient to confer a distinctive higher-order septin ultrastructure that can be further regulated by phosphorylation.

Unlabelled:  Nitric oxide (NO) signaling appears to play a vital role in wound healing associated to improve collagen and angiogenesis. A burn wound model was used to evaluate the effects of a chitosan films on histopathological features, nitric oxide synthase (NOS) activity, and quantification of neoformed capillaries assessed with CD34., Methods: Bilateral burns (n = 16) were made on adult Sprague-Dawley rats. The lesions on the right side of the rats were treated with chitosan films, and the lesions on the left side of the same rats were treated with gauze with NaCl 0.9% as a control., Results: Histological analysis revealed accelerated burn wound healing supported by significant differences in acute inflammation, collagen, and granulation tissue formation in chitosan-treated burns. Additionally, chitosan-treated burns were associated with higher CD34 immunoreactivity antibody supported by significant differences. This analysis of NOS activity was statistically significant on treated burns in the second treatment week. NOS results are associated with the highest collagen deposition, granulation tissue formation, and new capillary formation., Conclusion: The use of chitosan on burns promoted re-epithelialization by means of angiogenic and NO release associated with higher cell infiltration into the wound bed during the proliferative phase.

Septins are GTP-binding proteins that form ordered, rod-like multimeric complexes and polymerize into filaments, but how such supramolecular structure is related to septin function was unclear. In Saccharomyces cerevisiae, four septins form an apolar hetero-octamer (Cdc11-Cdc12-Cdc3-Cdc10-Cdc10-Cdc3-Cdc12-Cdc11) that associates end-to-end to form filaments. We show that septin filament assembly displays previously unanticipated plasticity. Cells lacking Cdc10 or Cdc11 are able to divide because the now-exposed subunits (Cdc3 or Cdc12, respectively) retain an ability to homodimerize via their so-called G interface, thereby allowing for filament assembly. In such cdc10Δ and cdc11Δ cells, the remaining septins, like wild-type complexes, localize to the cortex at the bud neck and compartmentalize nonseptin factors, consistent with a diffusion barrier composed of continuous filaments in intimate contact with the plasma membrane. Conversely, Cdc10 or Cdc11 mutants that cannot self-associate, but "cap" Cdc3 or Cdc12, respectively, prevent filament formation, block cortical localization, and kill cells., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Septins are a conserved family of GTP-binding proteins that assemble into symmetric linear heterooligomeric complexes, which in turn are able to polymerize into apolar filaments and higher-order structures. In budding yeast (Saccharomyces cerevisiae) and other eukaryotes, proper septin organization is essential for processes that involve membrane remodeling, such as the execution of cytokinesis. In yeast, four septin subunits form a Cdc11-Cdc12-Cdc3-Cdc10-Cdc10-Cdc3-Cdc12-Cdc11 heterooctameric rod that polymerizes into filaments thought to form a collar around the bud neck in close contact with the inner surface of the plasma membrane. To explore septin-membrane interactions, we examined the effect of lipid monolayers on septin organization at the ultrastructural level using electron microscopy. Using this methodology, we have acquired new insights into the potential effect of septin-membrane interactions on filament assembly and, more specifically, on the role of phosphoinositides. Our studies demonstrate that budding yeast septins interact specifically with phosphatidylinositol-4,5-bisphosphate (PIP2) and indicate that the N terminus of Cdc10 makes a major contribution to the interaction of septin filaments with PIP2. Furthermore, we found that the presence of PIP2 promotes filament polymerization and organization on monolayers, even under conditions that prevent filament formation in solution or for mutants that prevent filament formation in solution. In the extreme case of septin complexes lacking the normally terminal subunit Cdc11 or the normally central Cdc10 doublet, the combination of the PIP2-containing monolayer and nucleotide permitted filament formation in vitro via atypical Cdc12-Cdc12 and Cdc3-Cdc3 interactions, respectively., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Background: Altered blood glucose concentration is commonly observed in patients with sepsis, even among those without hypoglycemic treatments or history of diabetes mellitus. These alterations in blood glucose are potentially detrimental, although the precise relationship with outcome in patients with bacteremia has not been yet determined., Methods: A retrospective cohort study design for analyzing patients with Gram negative rod bacteremia was employed, with the main outcome measure being in-hospital mortality. Patients were stratified in quintiles accordingly deviation of the blood glucose concentration from a central value with lowest mortality. Cox proportional-hazards regression model was used for determining the relationship of same day of bacteremia blood glucose and death., Results: Of 869 patients identified 63 (7.4%) died. Same day of bacteremia blood glucose concentration had a U-shaped relationship with in-hospital mortality. The lowest mortality (2%) was detected in the range of blood glucose concentration from 150 to 160 mg/dL. Greater deviation of blood glucose concentration from the central value of this range (155 mg/dL, reference value) was directly associated with higher risk of death (p = 0.002, chi for trend). The low-risk group (quintile 1) had a mortality of 3.3%, intermediate-risk group (quintiles 2, 3 and 4) a mortality of 7.1%, and the high-risk group (quintile 5) a mortality of 12.05%. In a multivariable Cox regression model, the hazard ratio for death among patients in the intermediate-risk group as compared with that in the low risk group was 2.88 (95% confidence interval, 1.01 to 8.18; P = 0.048), and for the high risk group it was 4.26 (95% confidence interval, 1.41 to 12.94; P = 0.01)., Conclusions: Same day of bacteremia blood glucose concentration is related with outcome of patients with Gram-negative rod bacteremia. Lowest mortality is detected in patients with blood glucose concentration in an interval of 150-160 mg/dL. Deviations from these values are associated with an increased risk of death.

Objectives: Our aim was to access the incidence of late major adverse cardiac events (MACE) and stent thrombosis (ST) in nonselected, complex patients followed for a period >/=4 years., Background: Despite the efficacy of drug-eluting stents (DES) in reducing repeated target lesion revascularization, concerns regarding the occurrence of late and very late ST have partially obscured the benefits of this novel technology., Methods: All consecutive patients treated solely with DES between May 2002 and January 2005 were enrolled into this prospective, nonrandomized, single-center registry. The primary end point was long-term occurrence of MACE up to 7 years. Independent predictors of MACE, cardiac death, target lesion revascularization, and ST were obtained by a multivariate Cox proportional hazards regression model., Results: A total of 1,010 patients were enrolled. Most of them were men (77%) with a mean age of 63.7 years. Stent/patient rate was 1.4. Patients were kept in dual antiplatelet therapy for 3 and 6 months after Cypher (Cordis, Johnson & Johnson, Miami Lakes, Florida) and Taxus (Boston Scientific Corp., Natick, Massachusetts) stent implantation, respectively. Follow-up was obtained in 98.2% of the cohort (median 5.01 years). Survival free of MACE and cumulative incidence of definite/probable ST were 84.6% and 1.7%, respectively. Independent predictors of ST were percutaneous coronary intervention in the setting of acute myocardial infarction, DES overlapping, treatment of multivessel disease, presence of moderate-to-severe calcification at lesion site, and in-stent residual stenosis., Conclusions: The deployment of DES in complex, real-world patients resulted in a low rate of very long-term MACE and ST. However, ST still occurs very long after the index procedure., (Copyright (c) 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Chlorpromazine (CPZ), a potent nicotinic acetylcholine receptor (nAChR) noncompetitive antagonist, binds with higher affinity in the ion channel in the desensitized state than in the closed channel state and with low affinity to additional sites in nAChR-rich membranes. For nAChR equilibrated with agonist, we confirm previous reports that [(3)H]CPZ occupies a site near the cytoplasmic end of the M2 ion channel domain, photolabeling positions M2-2, M2-6, and/or M2-9 in each subunit. We find that [(3)H]CPZ also binds at the extracellular end of the channel, photolabeling amino acids at positions M2-16 (alpha,gamma), M2-17 (alpha,beta,delta), and M2-20 (alpha,beta,delta). The photolabeling at the cytoplasmic end of the channel is fully inhibitable by phencyclidine or proadifen, whereas neither drug inhibits [(3)H]CPZ photolabeling at the extracellular end, establishing that positively charged drugs can bind simultaneously at the cytoplasmic and extracellular ends of the ion channel. [(3)H]CPZ photolabeling is not detected in the transmembrane domain outside the ion channel, but it photolabels alphaMet-386 and alphaSer-393 in the cytoplasmic alphaMA helix. In the nAChR equilibrated with alpha-bungarotoxin to stabilize the nAChR in a closed state, [(3)H]CPZ photolabels amino acids at M2-5 (alpha), M2-6 (alpha,beta,delta), and M2-9 (beta,delta), with no labeling at M2-2. These results provide novel information about the modes of drug binding within the nAChR ion channel and indicate that within the nAChR transmembrane domain, the binding of cationic aromatic amine antagonists can be restricted to the ion channel domain, in contrast to the uncharged, allosteric potentiators and inhibitors that also bind within the delta subunit helix bundle and at subunit interfaces.

Aims: Drug-eluting stents (DES) have become the first choice to treat BMS restenosis (ISR), replacing brachytherapy and all other available percutaneous approaches. Although markedly reduced, DES ISR still occurs and has been frequently treated with another DES, despite the lack of robust data supporting the safety and efficacy of this approach. We sought to compare the long term clinical outcomes of patients with BMS and DES ISR treated with another DES deployment., Methods and Results: Between May 2002 and January 2008 a total of 158 patients with BMS restenosis and 58 patients with DES restenosis were treated with a DES and enrolled in this registry. Primary endpoint included the cumulative occurrence of major adverse cardiac events (MACE=cardiac death, myocardial infarction and target-vessel revascularisation) and stent thrombosis. Baseline clinical aspects did not significantly differ between the groups. There was a trend toward a higher incidence of DM in the DES cohort (36.1% vs. 32.9%, p=0.1). Mean time between first procedure and restenosis was significant longer in the DES population (178+/-61 days vs. 140+/-38 days, p=0.02). At the end of the follow-up period, 92.6% of the patients with BMS-ISR and 86.3% of those with DES-ISR were free of MACE (p<0.001). Patients with DES ISR had significant more recurrence of ISR but equivalent rates of cardiac death, MI and stent thrombosis., Conclusions: Percutaneous treatment of BMS or DES ISR with the implant of a DES represents a simple and safe approach with sustained long term results. However, the relatively high rate of ISR recurrence among patients with prior DES ISR demand the developing of more effective strategies for that subset of individuals.

Background: There is limited information about the effect of diabetes on the prognosis of patients with bacterial infections. We performed a retrospective cohort study to investigate possible correlations between diabetes and prognosis in patients with Enterobacteriaceae bacteremia., Methods: We reviewed the medical charts of 1112 patients who were treated at a community teaching hospital for Enterobacteriaceae bacteremia from January 1997 through June 2007. Factors associated with in-hospital mortality were analyzed by logistic regression analysis., Results: Among the 1112 patients with Enterobacteriaceae bacteremia, 181 (16.3%) were diabetic patients; 90 patients (8.1%) died while in the hospital. Compared to non-diabetic patients, diabetic patients were older (75.4 +/- 11.9 years vs. 70 +/- 16.6 years, p < 0.001) and had more comorbidities. However, mortality among diabetic and non-diabetic patients was not different [7.2% vs. 8.2%, RR 1.13; 95% CI (0.67-1.9); p = 0.39]. In a multivariate analysis, the variables associated with in-hospital mortality were age, the origin of the bacteremia, and the presence of immunosuppression. Diabetes was not associated with outcome., Conclusion: In this cohort of patients with Enterobacteriaceae bacteremia, diabetes was not associated with a poorer prognosis.

The kinetics and mechanism of the thermal activation of peroxydisulfate, in the temperature range from 60 to 80 degrees C, was investigated in the presence and absence of sodium formate as an additive to turn the oxidizing capacity of the reaction mixture into a reductive one. Trichloroacetic acid, TCA, whose degradation by a reductive mechanism is well reported in the literature, was used as a probe. The chemistry of thermally activated peroxydisulfate is described by a reaction scheme involving free radical generation. The proposed mechanism is evaluated by a computer simulation of the concentration profiles obtained under different experimental conditions. In the presence of formate, SO(4)(-) radicals yield CO(2)(-), which are the main species available for degrading TCA. Under the latter conditions, TCA is more efficiently depleted than in the absence of formate, but otherwise identical conditions of temperature and [S(2)O(8)(2-)]. We therefore conclude that activated peroxydisulfate in the presence of formate as an additive is a convenient method for the mineralization of substrates that are refractory to oxidation, such as perchlorinated hydrocarbons and TCA. This method has the advantage that leaves no toxic residues.

Objectives: We sought to assess the safety and efficacy of the novel VESTAsync-eluting stent (MIV Therapeutics, Atlanta, Georgia) combining a stainless steel platform with a nanothin-microporous hydroxyapatite surface coating impregnated with a polymer-free low-dose of sirolimus (55 microg)., Background: Durable polymers in first-generation drug-eluting stents (DES) have been linked to local inflammatory reaction leading to a positive vessel remodeling, late incomplete stent apposition, and in some cases, stent thrombosis. The removal of the polymer from the DES system could increase the safety profile of this novel technology., Methods: A total of 15 patients with single de novo lesions in native coronary arteries with 3.0- to 3.5-mm diameter and

Despite the undeniable contribution of intravascular ultrasound (IVUS) and quantitative coronary angiography (QCA) to assess drug-eluting stent (DES) effectiveness, the way these image modalities correlate to each other and to target-lesion revascularization (TLR) after PCI, is yet to be established. Thus we sought to evaluate whether there is an acceptable correlation between QCA and IVUS after DES implantation. We analyzed 204 pts treated with DES: Zotarolimus- (126), Sirolimus- (57), and Biolimus (31) with baseline and follow-up QCA and IVUS. The correlation between QCA lumen loss (LL) and intimal hyperplasia (IH) volume obstruction by IVUS was assessed by multiple regression analysis. Two QCA parameters (in-segment diameter stenosis and in-segment LL) and one IVUS variable (in-stent volume of IH) were evaluated as quantitative surrogates of 6 month TLR. The receiver operating characteristic method with c-statistics was used to assess the ability of each surrogate endpoint to predict TLR. QCA LL correlated positively with IVUS IH volume of obstruction (r = 0.69; CI95% 0.61-0.75: P < 0.0001), independent of DES type. The 2 QCA parameters were superior to the IVUS parameter as surrogates for TLR. Of note, QCA LL (c = 0.99) correlated best with TLR, even better than percent DS. In the DES era there is a good correlation between QCA measured LL and IVUS IH volume and therefore can be used as a surrogate of DES efficacy.

To describe the microbiology and outcome of iliopsoas abscess (IPA) in a large case series, we analyzed 124 cases of IPA collected from 1990 through 2004 in 11 hospitals in Spain. Twenty-seven (21.8%) patients had primary and 97 (78.2%) had secondary IPA. The main sources of infection were bone (50.5%), gastrointestinal tract (24.7%), and urinary tract (17.5%). A definitive microbial diagnosis was achieved in 93 (75%) cases. Abscess culture was the most frequent procedure leading to microbial diagnosis, followed by blood cultures. Staphylococcus aureus, Escherichia coli, and Bacteroides species were the most frequent microbial causes: S. aureus was the most common organism in patients with primary abscesses (42.9%) and with abscesses of skeletal origin (35.2%), whereas E. coli was the leading organism in those with abscesses of urinary (61.5%) and gastrointestinal (42.1%) tracts. Mycobacterium tuberculosis was found in 15 patients, 4 of them associated with human immunodeficiency virus (HIV) infection. Twenty (21.5%) cases had polymicrobial infections; these were more common among patients with abscesses of gastrointestinal origin. Information on clinical outcome was available for 120 patients; 19 (15.8%) had a relapse and 6 (5%) died due to complications related to the IPA. Patients who died were older and more likely to have bacteremia and E. coli isolated from cultures. In conclusion, secondary IPA is more prevalent than primary IPA. Among those with secondary IPA, most abscesses are secondary to a skeletal source. A bacterial etiology can be identified in most cases. The overall prognosis of patients with this condition is good.

Following a dramatic fall in tuberculosis, the last two decades have seen not only an increase in its overall frequency but also the extrapulmonary forms, including head and neck tuberculosis, have increased in proportion. Despite this rise, head and neck tuberculosis is still very rare, except for cervical adenitis. This fact and the non-specific nature of its presentation explain that tuberculosis is often an unexpected finding in biopsy results. Notwithstanding the advances in the diagnosis of tuberculosis, with ever speedier and more reliable tests such as polymerase chain reaction, its detection almost always requires the performance of invasive procedures such as punctures or biopsies. On the other hand, the diagnostic gold standard is still the culture of mycobacteria, a test that requires waiting times potentially of more than a month. The greatest recent advance in tuberculosis treatment is the existence of a pharmacological cure, making surgery practically unnecessary following diagnosis.

Etomidate, one of the most potent general anesthetics used clinically, acts at micromolar concentrations as an anesthetic and positive allosteric modulator of gamma-aminobutyric acid responses, whereas it inhibits muscle-type nicotinic acetylcholine receptors (nAChRs) at concentrations above 10 microm. We report here that TDBzl-etomidate, a photoreactive etomidate analog, acts as a positive allosteric nAChR modulator rather than an inhibitor, and we identify its binding sites by photoaffinity labeling. TDBzl-etomidate (>10 microm) increased the submaximal response to acetylcholine (10 microm) with a 2.5-fold increase at 60 microm. At higher concentrations, it inhibited the binding of the noncompetitive antagonists [(3)H]tetracaine and [(3)H]phencyclidine to Torpedo nAChR-rich membranes (IC(50) values of 0. 8 mm). nAChR-rich membranes were photolabeled with [(3)H]TDBzl-etomidate, and labeled amino acids were identified by Edman degradation. For nAChRs photolabeled in the absence of agonist (resting state), there was tetracaine-inhibitable photolabeling of amino acids in the ion channel at positions M2-9 (deltaLeu-265) and M2-13 (alphaVal-255 and deltaVal-269), whereas labeling of alphaM2-10 (alphaSer-252) was not inhibited by tetracaine but was enhanced 10-fold by proadifen or phencyclidine. In addition, there was labeling in gammaM3 (gammaMet-299), a residue that contributes to the same pocket in the nAChR structure as alphaM2-10. The pharmacological specificity of labeling of residues, together with their locations in the nAChR structure, indicate that TDBzl-etomidate binds at two distinct sites: one within the lumen of the ion channel (labeling of M2-9 and -13), an inhibitory site, and another at the interface between the alpha and gamma subunits (labeling of alphaM2-10 and gammaMet-299) likely to be a site for positive allosteric modulation.

Background: Despite the increasing number of elderly people, this high-complexity subset of patients is often excluded from randomized trials of percutaneous coronary intervention (PCI) and, therefore, limited data are available about their outcomes after drug-eluting stent (DES) implantation. We sought to compare the very long-term (> 1 year) clinical follow up of octogenarians treated with DES compared to younger individuals., Methods: The DESIRE registry is a prospective, nonrandomized, single-center registry with consecutive patients treated solely with DES between May 2002 and May 2007. The only exclusion criteria were the treatment of patients in the setting of acute myocardial infarction (MI) (< 72 hours) and lesions located in non-native coronary arteries. The primary endpoint was the occurrence of combined major adverse cardiac events (MACE) (cardiac death, non-fatal MI and target vessel revascularization) in-hospital and in very long term (> 1 year) follow up. Patients were clinically evaluated at 1, 3 and 6 months and then annually up to 5 years. Stent thrombosis was classified according to the ARC definition., Results: A total of 1,364 patients matched the inclusion/exclusion criteria and were sorted into 3 groups according to their ages: Group I = patients < 70 years of age (n = 914); Group II = patients greater than or equal to 70 and < 80 years of age (n = 334); and Group III = patients greater than or equal to 80 years old (n = 116). As expected, octogenarians had significantly more comorbid and complex anatomic lesion presentation. Nevertheless, in-hospital success was comparable among the 3 groups. Long-term (2.6 +/- 1.2 years) follow up was obtained from 97% of the total population and showed equivalent cumulative MACE in all age ranges (7.6% for < 70 years old vs. 5.4% for septuagenarians and 6.0% for octogenarians, p = 0.7). However, octogenarians had markedly more cardiac death, reflecting the severity of their comorbidity and the natural evolution of coronary disease. Of note, very few cases of stent thrombosis were noticed in the overall population (20 patients, 1.5%), with no difference among the groups., Conclusions: PCI with DES represents an efficient and safe approach to treat coronary artery disease in the elderly, with low rates of combined MACE comparable to other age ranges.

Background: Recently, cardiologists have treated more complex patients and lesions with drug-eluting stents (DES). However, long-term efficacy and safety of the off-label use of these new devices is yet to be demonstrated., Methods: The Drug-Eluting Stents in the Real World (DESIRE) registry is a prospective, nonrandomized single-center registry with consecutive patients treated solely with DES between May 2002 and May 2007. The primary end-point was long-term occurrence of major adverse cardiac events (MACE). Patients were clinically evaluated at 1, 3, and 6 months and then annually up to 5 years., Results: A total of 2,084 patients (2,864 lesions and 3,120 DES) were included. The mean age was 63.8 +/- 11.5 years. Diabetes was detected in 28.9% and 40.7% presented with acute coronary syndrome. Cyphertrade mark was the predominant DES in this registry (83.5%). Mean follow-up time was 2.6 +/- 1.2 years and was obtained in 96.5% of the eligible patients. Target lesion revascularization (TLR) was performed in 3.3% of the patients. Q wave myocardial infarction (MI) occurred in only 0.7% of these patients and total stent thrombosis rate was 1.6% (n = 33). Independent predictors of thrombosis were PCI in the setting of MI (HR 11.2; 95% CI, 9.6-12.4, P = 0.001), lesion length (HR 4.6; 95% CI, 3.2-5.3, P = 0.031), moderate to severe calcification at lesion site (HR 13.1; 95% CI, 12.1-16.7, P < 0.001), and in-stent residual stenosis (HR 14.5; 95% CI, 10.2-17.6, P < 0.001)., Conclusion: The use of DES in unselected population is associated with long-term safety and effectiveness with acceptable low rates of adverse clinical events.

Mitotic yeast cells express five septins (Cdc3, Cdc10, Cdc11, Cdc12, and Shs1/Sep7). Only Shs1 is nonessential. The four essential septins form a complex containing two copies of each, but their arrangement was not known. Single-particle analysis by EM confirmed that the heterooligomer is octameric and revealed that the subunits are arrayed in a linear rod. Identity of each subunit was determined by examining complexes lacking a given septin, by antibody decoration, and by fusion to marker proteins (GFP or maltose binding protein). The rod has the order Cdc11-Cdc12-Cdc3-Cdc10-Cdc10-Cdc3-Cdc12-Cdc11 and, hence, lacks polarity. At low ionic strength, rods assemble end-to-end to form filaments but not when Cdc11 is absent or its N terminus is altered. Filaments invariably pair into long parallel "railroad tracks." Lateral association seems to be mediated by heterotetrameric coiled coils between the paired C-terminal extensions of Cdc3 and Cdc12 projecting orthogonally from each filament. Shs1 may be able to replace Cdc11 at the end of the rod. Our findings provide insights into the molecular mechanisms underlying the function and regulation of cellular septin structures.

Chitosan acetate films have been prepared using chitosans from shrimps (Pleuroncodes monodon) of low and high molecular weight (LMv = 68,000 g/mol and HMv = 232,000 g/mol) and deacetylation degree of 80 and 100%, respectively. The chitosan films were obtained by addition of several additives to acetic acid chitosan solutions, such as: glycerol, oleic acid and linoleic acid in different proportions. The pH of the solutions before casting ranged from 5.0 to 6.0. The composite film thickness are reported. The films have been analyzed by FTIR showing characteristic bands corresponding to the additives. The scanning electron microscopy (SEM) studies reveals the different morphology of the composite films. The films exhibit different physical properties depending upon the additives and/or mixture of them. The addition of glycerol to composite improves the elasticity of the films. The swelling in glucose and saline solutions for several films was evaluated, being higher in the glucose solution. The bactericide test against Staphylococcus aureus, Pseudomona aeruginosa and Acinetobacter baumanii in plates with either blood and or agar tripticase showed that the molecular weight influences on the bactericidal properties of the chitosan composite films and over its effect against gram positive and gram negative bacteria. Medical applications of the composite films were done in patients with burns, ulcers and injuries, the films containing glycerol showed good adhesion in comparison with those without it. The composite films tested were mainly three (1) chitosan acetate with glycerol, (2) chitosan acetate with oleic acid and (3) chitosan acetate with glycerol and oleic acid. Excellent results in the skin recovery were obtained after 7-10 days. Since the chitosan is biodegradable by the body enzymes it does not need to be removed and increases the gradual grows of the damage tissues.

The structural and dynamical changes occurring before nucleotide addition were studied using molecular dynamics (MD) simulations of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) complexes containing one or two Mg2+ ions in the presence of dNTP. Our models revealed that the formation of a catalytically competent DNA polymerase complex required subtle rearrangements at the catalytic site A, which occurred only when an Mg2+ ion was bound. This model has been validated using pre-steady-state kinetics to show that free Mg2+ is necessary to obtain a catalytically competent polymerase. Kinetic studies carried out with Be2+ as a cofactor permitted the functional discrimination between metal sites A and B. At low concentrations, Be2+ increased the catalytic efficiency of the polymerase, while at higher concentrations, it competed with Mg2+ for binding to site A, and inhibited DNA polymerization. In agreement with experimental data, MD simulations revealed that the catalytic attack distance between the 3-OH of the primer and the phosphorus in complexes containing Be2+ instead of Mg2+ at site A was above 4.5 A. Our findings provide a detailed description of the mechanism of DNA polymerization and should be helpful to understand the molecular basis of DNA replication fidelity.

Objectives: We analyzed survival, therapeutic response, and prognostic factors in patients with HIV-related Hodgkin lymphoma (HL) treated or not with highly active antiretroviral therapy (HAART)., Methods: This study included 104 patients with HL, treated (n = 83) or not (n = 21) with HAART. Outcomes and prognostic factors of complete remission (CR), overall survival (OS), and disease-free survival (DFS) were assessed by an intention-to-treat analysis of all patients who received at least 1 chemotherapy course., Results: No differences were found between groups at baseline in the specific characteristics of HIV and HL. The proportion of patients receiving appropriate-for-stage therapy for HL was similar for both groups. The CR rates in the HAART (-) and HAART (+) groups were 14 (70%) of 20 versus 71 (91%) of 78 (P = 0.023). The median OS in the HAART (-) group was 39 months (95% confidence interval [CI]: 0 to 89) and was not reached in the HAART (+) group (P = 0.0089). The median DFS in the HAART (-) group was 85 months (95% CI: 73 to 97) and was not reached in the HAART (+) group (P = 0.129). Factors independently associated with CR by logistic regression analysis were appropriate-for-stage therapy of HL, HAART, and baseline CD4 count > or =100 cells/microL. CR was the only factor independently associated with OS by Cox regression analysis., Conclusions: The achievement of CR was independently associated with appropriate-for-stage therapy for HL, with HAART, and with a baseline CD4 count > or =100 cells/microL. The only variable independently associated with OS was the achievement of CR.

P-glycoprotein (PGP) is a membrane protein and product of the MDR-1 gene, which acts as an efflux pump for several drugs, such as protease inhibitors (PI) used in HIV. Numerous studies in vitro, in experimental animals, and in patients have analyzed the relationships between PGP and the pharmacokinetic and pharmacodynamic properties of antiretroviral agents, with differing conclusions. In addition, studies focusing on the impact of single nucleotide polymorphisms in the MDR-1 gene, mainly C3435T in exon 26 and G2677A/G2677T in exon 21, on antiretroviral plasma concentrations, efficacy and adverse effects, have reported varying results, which have been attributed to the influence of other polymorphisms, such as cytochrome P450.

Background/aims: Periodic limb movements are common in patients with end-stage renal disease. Kidney transplantation significantly improves renal function and may therefore reduce periodic limb movements. We evaluated the effect of kidney transplantation on periodic limb movements in a group of patients with end-stage renal disease., Methods: Eighteen patients (aged 27-65) who were receiving dialysis and were candidates for living donor or deceased donor kidney transplantation (n = 12) or were predialysis with a suitable living donor arranged (n = 6) were recruited from the transplant clinic. Attended overnight polysomnography was performed before and after kidney transplantation. Patients were divided based on a periodic limb movement index >15 events/h during sleep., Results: Kidney transplantation was associated with a significant reduction in periodic limb movement index in all patients (8 (0-110) events/h vs. 2 (0-80) events/h) and this reduction was greatest in 7 patients with a periodic limb movement index >15 events/h (40 (24-110) events/h to 14 (1-80) events/h, p < 0.005)., Conclusion: Successful kidney transplantation improves periodic limb movements in patients with end-stage renal disease. This may improve sleep quality and sleep-related quality of life in kidney transplant recipients, which should have a beneficial impact on clinical outcomes., (Copyright 2008 S. Karger AG, Basel.)

Background: Escherichia coli is the most frequent Gram-negative organism causing bacteraemia. There are few data about prognostic factors of bloodstream infections due to E. coli. In particular, the consequences of antibiotic resistance and of adequate empirical antibiotic treatment on outcome remain broadly unknown., Methods: We conducted a retrospective cohort study of patients with E. coli bacteraemia between January 1997 and June 2005 to identify any association between antibiotic resistance, adequacy of empirical antibiotic therapy and mortality., Results: Of 663 patients with E. coli bacteraemia, 36 (5.4%) died. Patients with multidrug-resistant (MDR) E. coli bacteraemia had a significantly lower frequency of correct empirical antibiotic treatment than patients with non-MDR E. coli bacteraemia [relative risk (RR) 0.53; 95% confidence interval (CI) 0.48-0.67], and also had a significantly higher mortality (RR 3.31; 95% CI 1.72-6.36). An association between the number of antibiotics to which E. coli was resistant with adequacy of empirical antibiotic (P < 0.001) and with mortality (P < 0.001) was detected. After adjustment for other significant risk factors and confounders, the inadequacy of empirical antibiotic treatment was associated with an increased mortality (adjusted OR 2.98; 95% CI 1.25-7.11). When the adequacy of empirical treatment was excluded from the model, the presence of MDR E. coli in blood cultures was also associated with the prognosis (adjusted OR 3.11; 95% CI 1.3-7.44). In multivariate analysis, other variables associated with the outcome were age, the presence of severe sepsis or shock, Charlson index score and a non-urinary origin of the bacteraemia., Conclusions: Adequacy of empirical antibiotic treatment is an independent risk factor for mortality in patients with E. coli bacteraemia. MDR E. coli bacteraemia had a worse prognosis due, at least in part, to a lower frequency of correct empirical treatment.

Background: Sleep apnoea is common in patients with end-stage renal disease. Although individual case reports have described an improvement in sleep apnoea following kidney transplantation, there have been no longitudinal studies of a case series to determine what proportion of patients with sleep apnoea improve., Methods: Dialysis-dependent patients awaiting kidney transplantation and pre-dialysis patients with an identified living donor kidney had overnight polysomnography, which was repeated several months after successful kidney transplantation. Patients were divided into apnoeic and non-apnoeic groups based on an apneoa-hypopnoea index (AHI) > 10/h during pre-transplant polysomnography and, following transplantation, apnoeic patients were further divided into responders and non-responders based on >50% reduction in AHI and/or AHI < 10/h., Results: Eighteen patients (11 men, 7 women), aged 27-65, were studied. Pre-transplant sleep apnoea was present in 11 of 18 (61%) patients. Although transplantation was associated with a significant reduction in blood urea nitrogen and serum creatinine, there were no significant changes in AHI (pre vs post: 20.2 +/- 15.1 vs 23.5 +/- 21.3). Among the 11 apnoeic patients, only three met the criteria for a significant improvement ('responder'). There were no patient characteristics, sleep apnoea indices or renal function changes that distinguished responders from non-responders., Conclusions: Sleep apnoea improves in a minority of patients with end-stage renal disease following successful kidney transplantation. Specific determinants of improvement were not identified.

Interactions of benzophenone (BP) with the Torpedo nicotinic acetylcholine receptor (nAChR) were characterized by electrophysiological analyses, radioligand binding assays, and photolabeling of nAChR-rich membranes with [3H]BP to identify the amino acids contributing to its binding sites. BP acted as a low potency noncompetitive antagonist, reversibly inhibiting the ACh responses of nAChRs expressed in Xenopus oocytes (IC50 = 600 microM) and the binding of the noncompetitive antagonist [3H]tetracaine to nAChR-rich membranes (IC50 = 150 microM). UV irradiation at 365 nm resulted in covalent incorporation of [3H]BP into the nAChR subunits (delta > alpha approximately beta > gamma), with photoincorporation limited to the nAChR transmembrane domain. Comparison of nAChR photolabeling in the closed state (absence of agonist) and desensitized state (equilibrated with agonist) revealed selective desensitized state labeling in the delta subunit of deltaPhe-232 in deltaM1 and deltaPro-286/deltaIle-288 near the beginning of deltaM3 that are within a pocket at the interface between the transmembrane and extracellular domains. There was labeling in the closed state within the ion channel at position M2-13 (alphaVal-255, betaVal-261, and deltaVal-269) that was reduced by 90% upon desensitization and labeling in the transmembrane M3 helices of the beta and gamma subunits (betaMet-285, betaMet-288, and gammaMet-291) that was reduced by 50-80% in the desensitized state. Labeling at the lipid interface (alphaMet-415 in alphaM4) was unaffected by agonist. These results provide a further definition of the regions in the nAChR transmembrane domain that differ in structure between the closed and desensitized states.

Objective: To evaluate the effectiveness and tolerability of a simplification regimen with tenofovir DF (TDF), lamivudine (3TC), and efavirenz (EFV) in HAART-experienced HIV-1-infected subjects with sustained viral suppression., Method: Patients with HIV-1 RNA <200 copies/mL during the previous 6 months and who switched their current twice-daily or three-times-daily HAART to a simplified once-daily regimen of TDF (300 mg), 3TC (300 mg), and EFV (600 mg) were included., Results: 154 patients (70% males, mean age 42 years) were included. Previous HAART included a non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimen in 55% of the patients and a thymidine analog in 87%. The percentage of patients with viral load <200 copies/mL in the intent-to-treat (ITT) data set was 83% at 6 months and 75% at 12 months (98% and 96%, respectively, in the on-treatment [OT] analysis). Five patients (3%) were identified as virologic failures according to the study protocol. The mean CD4 T-cell count increased significantly 12 months after simplification (from 570 to 632 cells/mm3; p < .01). At 12 months, mean triglyceride levels decreased from 233 to 170 mg/dL (p < .01) and mean cholesterol levels decreased from 205 to 189 mg/dL (p < .01). Thirty-three patients (21%) discontinued the study treatment prior to completing the 12-month follow-up., Conclusion: Simplification to a once-daily regimen containing TDF, 3TC, and EFV is virologically and immunologically effective, well-tolerated, and safe with benefits in the lipid profile in the majority of patients.

Background: Lately drug-eluting stents (DES) have dramatically reduced restenosis rates and need for repeat revascularization in a wide subset of lesion and patients. However, their benefit for the treatment of large vessels (> 3.0 mm) has yet to be established., Objective: We investigated whether DES are superior to bare metal stents (BMS) in terms of clinical outcomes for the treatment of large coronary vessels., Methods: This study assessed the long-term outcomes (cardiac death, acute myocardial infarction, and need for repeat intervention in the treated vessel) of patients treated with either a DES (Cypher and Taxus) or a BMS of > or = 3.5 mm in diameter. A total of 250 consecutive patients who underwent DES implantation were clinically followed for 1 year and compared to 250 patients who were treated with BMS. Interventions in the setting of acute ST elevation myocardial infarction and treatment of bypass grafts were excluded., Results: Cypher was the DES deployed in 70.8% of cases. Most of the enrolled patients were men (78%) with single vessel disease (65.6%). The left anterior descending artery was the culprit vessel in 34.2% of cases. Bare metal stent and DES cohorts had equivalent interpolated reference vessel diameter (3.19 +/- 0.3 mm for BMS vs 3.18 +/- 0.2 for DES; P = .1). Lesion was significantly longer in the group treated with DES (13.4 +/- 5.1 mm for BMS group vs 14.3 +/- 3.5 for DES; P = .0018). After 1 year of clinical follow-up, 95.2% of patients treated with DES and 91.2% of the patients who received BMS were free of major events (P = .2). A trend toward higher target-lesion revascularization was noticed in the group treated with BMS (4.8% vs 1.6%; P = .07)., Conclusion: Percutaneous treatment of large coronary vessels carries a low risk of clinical events irrespective of the type of stent used.