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Background: Voltage-dependent K+ (Kv) channels exist as tetramers of subunits consisting of six transmembrane segments (S1-S6). The S1 through S4 segments assemble into a voltage-sensing domain (VSD) that detects the membrane electric field. Therefore, the S4 is rich in positively charged amino acid residues forming the main component of the VSD. Upon membrane de- or repolarization, these positive charges, termed gating charges, cross the electric field, causing the VSD to change conformation. The S1-S3 segments surround the S4 and shape the electric field sensed by these gating charges.Materials and Methods: In the Shaker-type hKv1.5 channel residues C268 to R279 at the extracellular end of S1 and beginning of the S1-S2 linker were substituted by either a positive (lysine), a negative (glutamic acid), or a neutral (glutamine) residue. The charge substitution or charge introduction mutants were functionally analyzed by expressing the channels in Ltk- cells and performing patch-clamp current recordings.Results: At positions C268, L269, T271, and P273, a charge introduction was not tolerated, yielding no current expression. On the contrary, mutants D277K and R279E yielded channels with gating properties similar to wild type (WT) hKv1.5. The mutants E270Q, L272E, L272K, and F275K shifted the voltage dependence of channel activation toward more positive potentials compared to hKv1.5. However, this shift was accompanied by a shallower slope factor and altered activation and/or deactivation kinetics. Interestingly, at positions E274, R276, and E278, a charge substitution shifted the voltage dependence of channel opening without affecting channel kinetics, that is, exerting a surface charge effect.Conclusion: The cluster of charged residues at the top of S1 and the beginning of the S1-S2 linker are sufficiently close to the S4 and offset (polarize) the electric field sensed by the S4, contributing to the voltage dependence of channel activation.

Purpose To evaluate the differences when performing the sentinel lymph node biopsy (SLNB) before or after neoadjuvant endocrine therapy (NET) in breast cancer patients, and the impact of its timing on prognosis. Methods A retrospective cohort study including 91 postmenopausal cases with clinically node-negative and hormone receptor-positive/HER2 negative (HR+/HER2-) breast cancer, treated with NET and SLNB at our institution. SLNB was performed pre-NET until 2014, and post-NET thereafter. Axillary lymph node dissection (ALND) was indicated only in SLNB-macrometastasis, although in selected elderly patients it was omitted. Kaplan-Meier survival curves were obtained in relation to the status of the axilla, and the differences assessed using the log-rank test. Results Between December 2006 and March 2022, SLNB was performed pre-NET in 14 cases and post-NET in 77. SLNB-positivity was similar regardless of whether SLNB was performed before or after NET (35.7% and 37%, respectively), with 2/14 SLN macrometastases in the pre-NET cohort and 17/77 in the post-NET cohort. Only three patients (18.7%) with SLN macrometastasis had > 3 positive nodes following axillary node dissection. The 5-year overall survival and distant disease-free survival were 92.4% and 94.8% respectively, with no significant differences according to SLNB status. Conclusion SLN positivity did not differ according to its timing (before or after NET). Therefore, NET has no effect on lymph node clearance. Furthermore, the prognosis is good regardless of the axillary involvement. Therefore, factors other than axillary involvement may affect the prognosis in these patients.

Voltage-gated K + (Kv) channels mediate the flow of K + across the cell membrane by regulating the conductive state of their activation gate (AG). Several Kv channels display slow C-type inactivation, a process whereby their selectivity filter (SF) becomes less or nonconductive. It has been proposed that, in the fast inactivation-removed Shaker-IR channel, the W434F mutation epitomizes the C-type inactivated state because it functionally accelerates this process. By introducing another pore mutation that prevents AG closure, P475D, we found a way to record ionic currents of the Shaker-IR-W434F-P475D mutant at hyperpolarized membrane potentials as the W434F-mutant SF recovers from its inactivated state. This W434F conductive state lost its high K + over Na + selectivity, and even NMDG + can permeate, features not observed in a wild-type SF. This indicates that, at least during recovery from inactivation, the W434F-mutant SF transitions to a widened and noncationic specific conformation.

Introduction Daily, moderate hypofractionation has become standard treatment for breast cancer following breast-conserving surgery, although substantial variation exists in its use. This paper describes the generation of consensus-based recommendations for the utilisation of this therapy at the healthcare system level and compares these to American Society for Radiation Oncology (ASTRO) guidelines. Materials and methods Consensus-based guidelines were developed in three steps, including a systematic literature review and involvement of radiation oncologists specialising in breast cancer in Catalonia: (a) creation of a working group and evidence review; (b) consideration of the levels of evidence and agreement on the formulation of survey questions; and (c) performance of survey and development of consensus-based recommendations. Results were compared to the ASTRO recommendations. Results Consensus was above 80% for 10 of the 14 survey items. Experts supported hypofractionated radiotherapy for all breast cancer patients aged 40 years or more; with invasive carcinoma and breast-conserving surgery; without radiation of lymph nodes; and regardless of the tumour size, histological grade, molecular subtype, breast size, laterality, other treatment characteristics, or need for a boost. Over half favoured its use in all situations, even where available scientific evidence is insufficient. The resulting recommendations and the quality of the evidence are comparable to those from ASTRO, despite some differences in the degree of consensus. Conclusion Specialists agree that hypofractionation is the standard treatment for breast cancer following breast-conserving surgery, but some specific areas require a higher level of evidence before unequivocally extending indications.

Only 15 years ago pistachio was an almost unknown crop in Spain and Portugal. However, nowadays pistachio production has become a benchmark in terms of profitability of agricultural products. Currently the cultivated area is larger than 15,000 ha and the growth rate is over 40% year-1. The reasons for this are: firstly, the good prices at the point of origin, (with a continuous growth during the last 6 years), and secondly, because of the good adaptation of pistachio tree to the agroclimatic conditions in the interior of the Iberian Peninsula. As well, these conditions have favored the production of organic pistachio, which has a very important demand and a high difference with the conventional pistachio price (> € 2 kg-1). “El Chaparrillo”, an Agro-Environmental Research Center (CAC) has led this change, thanks to the research, experimentation and agricultural outreach done by it. Particularly relevant for the spreading of technical knowledge are two governmental initiatives; the first one is the virtual community for professionals involved in pistachio production, which includes news and events from sector and a public forum to solve technical questions. And the other is the operational group for the sustainable production of quality pistachio, included in the European Association for Innovation in Productivity and Agricultural Sustainability, (EAI-AGRI), with EU financial support.

Aim To evaluate the association between dose–volume histogram (DVH) values in organs at risk (OAR) and patient-reported HRQoL outcomes. Background Data on the association between DVHs and health-related quality of life (HRQoL) in prostate cancer (PCa) patients are limited. Materials and methods Five-year follow-up study of 154 patients with organ-confined (stage T1/T2) PCa treated with EBRT between January 2003 and November 2005. HRQoL was evaluated with the Expanded Prostate Cancer Index (EPIC). DVH for OARs (penile bulb, rectum and bladder) were created for all patients for whom data were available (119/154; 77%). The functional data analysis (FDA) statistical method was used. HRQoL data was collected prospectively and data analysis was performed retrospectively. Results Worsening of urinary incontinence and obstructive symptoms correlated with higher DVH dose distributions at 24 months. Increased rectal bleeding at months 24 and 60 correlated with higher DVH dose distributions in the 40–70 Gy range. Patients with deterioration in rectal incontinence presented a higher DVH distribution range than patients without rectal incontinence. Penile bulb DVH values and erectile dysfunction were not significantly associated. Conclusions DVH parameters and post-radiotherapy HRQoL appear to be closely correlated, underscoring the importance of assessing DVH values prior to initiating EBRT to determine the risk of developing HRQoL related adverse effects. Advanced treatment modalities may be appropriate in high risk cases to minimize treatment-related toxicity and to improve treatment outcomes and HRQoL. Future studies are needed to better elucidate the association between pre-treatment DVH parameters in organs at risk and subsequent HRQoL.

Objectives: To analyse lipid changes and tolerability in a cohort of HIV-infected patients who switched their anti- retroviral regimens to rilpivirine/emtricitabine/tenofovir (RPV/FTC/TDF) in a real-world setting. Methods: PRO-STR is a 48 week prospective observational post-authorization study in 25 hospitals. Patients with a viral load

The marine polycyclic-ether toxin gambierol and 1-butanol (n-alkanol) inhibit Shaker-type Kv channels by interfering with the gating machinery. Competition experiments indicated that both compounds do not share an overlapping binding site but gambierol is able to affect 1-butanol affinity for Shaker through an allosteric effect. Furthermore, the Shaker-P475A mutant, which inverses 1-butanol effect, is inhibited by gambierol with nM affinity. Thus, gambierol and 1-butanol inhibit Shaker-type Kv channels via distinct parts of the gating machinery.

To present survival and toxicity outcomes in patients with clinically localized, non-metastatic prostate cancer (PCa) treated with external beam radiotherapy (EBRT) combined with androgen deprivation therapy (ADT).Retrospective study of 849 PCa patients (pts) treated from 1996 to 2005. Until August 2000, all patients (281) were treated with conventional dose EBRT (76 Gy); subsequent pts received ≥76 Gy (565 pts). Median age was 70 years (range, 39-82). Most pts were intermediate (353; 42.8%) or high-risk (344; 41.7%). Mean PSA was 10.1 ng/ml. Median dose to the prostate was 75 Gy. Complete ADT was administered to 525 pts (61.8%).Median follow-up was 109.6 months (range, 68.3-193.4). Overall survival (OS) was 92.5% and 81.1% at 5 and 10 years; by risk group (low, intermediate, high), 5- and 10-year OS rates were 94.3% and 85.9%, 92.3% and 79.2%, and 91.9% and 80.2% (p = 0.728). Five- and 10-year BRFS was 94.1% and 80.6% (low risk), 86.4% and 70.9% (intermediate), and 85.2% and 71.4% (high) (p = 0.0666). Toxicity included rectitis: grade 1 (G1) (277 pts; 32.6%), G2 (108; 12.7%), and G3 (20; 2.6%) and urethritis: G1 (294; 34.6%); G2 (223; 26.2%), and G3 (11; 1.3%). By dose rate (76 Gy vs. ≥76 Gy), 5 and 10-year BRFS rates were 83.1% and 68.3% vs. 88.4% and 74.8% (p = 0.038).Our results are comparable to other published series in terms of disease control and toxicity. These findings confirm the need for dose escalation to achieve better biochemical control and the benefits of ADT in high-risk PCa patients.

This innovative practice full paper describes an effort to create a thread of engineering leadership development throughout an undergraduate engineering degree at The University of Texas at El Paso. The first bachelor’s degree of its kind in the nation, this new degree is housed in the Department of Engineering Education and Leadership and has a heavy emphasis on integrating fundamental engineering theory and skills with business acumen and leadership development (e-lead.utep.edu). In developing the leadership component of the degree, the faculty understood that one of the most effective methods by which people learn to develop as leaders is through practice. Therefore, rather than place all leadership development in a single course in the Engineering Leadership Program (E-Lead), the degree was designed to have a coordinated thread of leadership development throughout the degree plan, encompassing both curricular and extracurricular opportunities. Focused heavily on practice and application, a framework for leadership development was designed to take a tiered approach. For all students, in-class activities introduce fundamental concepts of engineering leadership in the context of teamwork and engineering project management in the E-Lead courses. For those students interested in more in-depth experience and training, additional extracurricular leadership development opportunities were made available in the form of coaching or attending leadership conferences and workshops. In all of these activities, the focus is on helping students to develop their character, capacity, and competence. Having recently graduated the first cohort of students using this leadership development approach, this paper describes the framework used for leadership development and the key activities dispersed throughout the engineering leadership thread. Further, this paper includes qualitative results from assessing the impact of these activities on our graduating cohort.

Purpose To analyze the results of exclusive brachytherapy (BT) to treat patients with penile squamous cell carcinoma confined to the glans or prepuce. Methods and Materials Retrospective analysis of 25 patients treated for T1–T2 penile cancer with exclusive interstitial BT between July 1989 and March 2014 at our institution. Results Median followup was 9.2 years (range, 0–19). The mean patient age was 65.3 years (range, 51–80). Most patients underwent exclusive low-dose-rate BT (56%; n = 14) or pulsed-dose-rate BT (40%; n = 10). Only 1 patient received high-dose-rate BT (4%). The median prescribed dose was 60 Gy. Eight patients died during follow-up because of systemic progression (one case) and other intercurrent causes (seven cases). Two failures were recorded (one local and one regional), both at 4 months after BT. The remaining patients continued follow-up at our institution and maintained response. Two patients underwent partial phallectomy for toxicity. At the time of this report, 12 of the 25 patients are alive and free of disease. The most common late toxicities were telangiectasia, urethral stenosis, and atrophy, in 48%, 43%, and 17.4% of patients, respectively. Conclusions BT with low dose rate/pulsed dose rate provides excellent locoregional control for small (≤4 cm) T1–T2 squamous cell carcinoma of the penile glans.

Introduction Prostate cancer (PCa) is the second leading cause of cancer mortality in western countries. Prostate tumours initially respond well to androgen-deprivation therapy (ADT). Unfortunately, the majority of tumours evolve, after androgen deprivation, from a hormone-sensitive to a castration-resistant prostate cancer (CRPC). For that reason new agents, targeting the androgen receptor (AR) pathway (abiraterone, enzalutamide among others), have been approved in the last decade. Unfortunately, the emergence of resistance to these treatments is common and CPRC remains highly lethal. Therefore, new approaches and better knowledge of the molecular mechanisms leading to CRPC is still needed. Mechanisms related to CRPC transition include increased expression of AR and activating mutations in this receptor. As in other tumours, there are other signalling pathways that could interfere with AR activation such as Wnt signalling pathway, which has been suggested to play an important role in CRPC. On the other hand, emerging evidences indicate that certain miRNAs are involved in the appearance of treatment resistances in several diseases. The aim of this project was to study miRNA and mRNA expression profiles to identify deregulated miRNAs and genes involved in the Wnt signalling pathway in CRPC. Material and methods A set of 20 PCa tumour samples, 10 radical prostatectomy (RP) specimens from hormone-naive patients vs 10 transurethral resection of prostate (TURP) samples from castration resistant patients, were analysed. Total RNA was obtained to study miRNA and mRNA expression using Affymetrix GeneChip miRNA 4.0 and GeneChip Clariom S human arrays, respectively. To identify deregulated miRNAs and their corresponding predicted target mRNA related to AR and Wnt signalling pathways, both miRNA and mRNA expression profiles were integrated by correlation analysis using the TAC software (appliedbiosystems). Results and discussions When hormone-naive samples vs. castration-resistant samples were compared, 62 miRNAs and 1023 mRNAs were significantly deregulated. Further identification of potential target genes found a strong correlation between hsa-miR-205–5 p, AR and Wnt5A, and between hsa-miR425-5p and GSK3β. In addition, expression of hsa-miR-425–5 p correlated with survival (2-tailed Student’s t test, p-value Conclusion Integrated analysis of miRNA and mRNA expression profiles is a useful tool to identify novel therapeutic targets for CPRC. The role of miRNAs involved in CRPC deserves further investigation.

Purpose Earlier studies evaluating the effect on quality of life (QoL) of localized prostate cancer interventions included patients receiving adjuvant hormone therapy, which could have affected their outcomes. Our objective was to compare the QoL impact of the three most common primary treatments on patients who were not receiving adjuvant hormonal treatment. Patients and Methods This was a prospective study of 435 patients treated with radical prostatectomy, external-beam radiotherapy, or brachytherapy. QoL was assessed before and after treatment with the Short Form-36 and the Expanded Prostate Cancer Index Composite. Differences between groups were tested by analysis of variance. Distribution of outcome at 3 years was examined by stratifying according to baseline status. Generalized estimating equation models were constructed to assess the effect of treatment over time. Results Compared with the brachytherapy group, the prostatectomy group showed greater deterioration on urinary incontinence and sexual scores but better urinary irritative-obstructive results (−18.22, −13.19, and +6.38, respectively, at 3 years; P < .001). In patients with urinary irritative-obstructive symptoms at baseline, improvement was observed in 64% of those treated with nerve-sparing radical prostatectomy. Higher bowel worsening (−2.87, P = .04) was observed in the external radiotherapy group, with 20% of patients reporting bowel symptoms. Conclusion Radical prostatectomy caused urinary incontinence and sexual dysfunction but improved pre-existing urinary irritative-obstructive symptoms. External radiotherapy and brachytherapy caused urinary irritative-obstructive adverse effects and some sexual dysfunction. External radiotherapy also caused bowel adverse effects. Relevant differences between treatment groups persisted for up to 3 years of follow-up, although the difference in sexual adverse effects between brachytherapy and prostatectomy tended to decline over long-term follow-up. These results provide valuable information for clinical decision making.

Purpose The objective of this study was to report initial outcomes in patients with locally advanced prostate cancer (CaP) who underwent external beam radiation therapy (EBRT) treatment combined with high-dose-rate brachytherapy (HDR-BT) as a boost. Methods and Materials From 2002 to 2007, 114 CaP patients underwent EBRT followed by 192 I HDR-BT. The patients were classified into intermediate- (Group 1) or high- (Group 2) risk groups. The mean total EBRT dose was 60.0 Gy (95% confidence interval [CI]: 59.9–60.1) at 2 Gy per fraction. After a mean of 20.6 days (95% CI: 18.4–22.8), all the patients received a single-fraction 9-Gy dose of HDR-BT boost. Of the 114 patients in the study, 103 (90.4%) underwent up to 3 years of complete androgen deprivation therapy after diagnosis. Results The mean followup for the entire group was 32.1 months (95% CI: 29.9–34.4). The 4-year biochemical failure-free survival rate was 97.4% and treatment was well-tolerated. Conclusions Preliminary biochemical control rates after EBRT plus one fraction of 9-Gy HDR-BT are encouraging. This atypical fractionation schedule is cost-effective and reduces patient discomfort and treatment-related risks. More followup is required to confirm these findings.

The objective was to compare the short- and long-term impact of 3 different treatment modalities on health-related quality of life (HRQOL) in patients treated for localised prostate cancer at a single centre in Catalonia, Spain.This was a longitudinal, prospective study of 304 patients from a single centre in Catalonia, Spain. Patients underwent 1 of 3 treatment procedures: radical prostatectomy (114 patients), external beam radiation (134) or interstitial brachytherapy (56). HRQOL was assessed by both general and specific questionnaires, including the SF-36 health survey and the Expanded Prostate Cancer Index Composite (EPIC). Interviews were administered prior to treatment and at months 1, 3, 6, 12 and 24. One-way analysis of variance and generalised estimating equations models were constructed to assess between group differences in HRQOL.After initial deterioration, HRQOL scores partially recovered, although significant differences between treatment groups persisted at two years. Worsening of urinary incontinence was especially marked for the radical prostatectomy group (11.45, p=0.005), while deterioration in the urinary irritative/obstructive domain was worse following brachytherapy treatment (4.76, p=0.025). Decline in sexual function was significantly greater for the radical prostatectomy group than for the brachytherapy group (18.74, p0.001). No significant between-group differences were observed in bowel domain scores.Quality of life 2 years after treatment for prostate cancer shows wide variability. Radical prostatectomy had the largest negative impact on the sexual and urinary incontinence domains. Differences between external radiation and brachytherapy were relatively small. Brachytherapy led to a moderate increase in urinary irritation compared to the other 2 groups.

Background and purpose: Chlorthalidone is used for the treatment of hypertension as it produces a lengthening of the cardiac action potential. However, there is no experimental evidence that chlorthalidone has electrophysiological effects on the potassium currents involved in cardiac repolarization. Experimental approach: Ventricular myocytes and oocytes, transfected with human ionic channels that produce IK current, were exposed to different concentrations of chlorthalidone. Action potentials and potassium currents were recorded using a patch clamp technique. To determine which component of the current was affected by chlorthalidone, human channel proteins (hERG, minK and KvLQT1) were used. Key results: Chlorthalidone prolonged the ventricular action potential at 50 and 90% by 13 and 14%, respectively. The cardiac potassium currents Ito and IK1 were not affected by chlorthalidone at any concentration, whereas the delayed rectifier potassium current, IK, was blocked in a dose-response, voltage-independent fashion. In our preparation, 100 μM chlorthalidone blocked the two components of the delayed rectifier potassium current with the same potency (50.1±5% for IKr and 54.6±6% for IKs) (n=7, P

Alkanols are small aliphatic compounds that inhibit voltage-gated K+ (Kv) channels through a yet unresolved gating mechanism. Kv channels detect changes in the membrane potential with their voltage-sensing domains (VSDs) that reorient and generate a transient gating current. Both 1-Butanol (1-BuOH) and 1-Hexanol (1-HeOH) inhibited the ionic currents of the Shaker Kv channel in a concentration dependent manner with an IC50 value of approximately 50 mM and 3 mM, respectively. Using the non-conducting Shaker-W434F mutant, we found that both alkanols immobilized approximately 10% of the gating charge and accelerated the deactivating gating currents simultaneously with ionic current inhibition. Thus, alkanols prevent the final VSD movement(s) that is associated with channel gate opening. Applying 1-BuOH and 1-HeOH to the Shaker-P475A mutant, in which the final gating transition is isolated from earlier VSD movements, strengthened that neither alkanol affected the early VSD movements. Drug competition experiments showed that alkanols do not share the binding site of 4-aminopyridine, a drug that exerts a similar effect at the gating current level. Thus, alkanols inhibit Shaker-type Kv channels via a unique gating modifying mechanism that stabilizes the channel in its non-conducting activated state.

Purpose To demonstrate the utility of a boost with interstitial brachytherapy (BT) in breast-conserving therapy (BCT) by doing a thorough review of the literature and describing in detail our technique for delivering this boost. Material and methods Our department has been delivering the boost with interstitial BT since 1989, in most cases with rigid needles and a theoretical dosimetry. In the early years, we used low-dose-rate (LDR) with iridium-192 wires. The dose administered was 15 Gy if there were no risk factors for local relapse or 20-25 Gy in the presence of risk factors. The risk factors considered were the presence of a close margin (less than 10 mm) and an extensive intraductal component (more than 25%). After 2002, we switched to high-dose-rate (HDR); using the linear quadratic model we changed the low dose to 3 fractions of 4.5 Gy in the case of no risk factors for local relapse or to 3 fractions of 5 Gy in the presence of risk factors. Results In 79 consecutive boost patients treated in our department between 2010 and 2011, with a median follow-up of 46 months, the local control rate was 97.47%. With respect to cosmesis, fibrosis occurred in 17 cases (21.5%) and hyperpigmentation in 26 cases (32.9%). Our hospital's results are comparable in terms of local control and cosmesis to those of other authors. Conclusions This educational article describes our department's boost technique with rigid needles and comments briefly on our results using this technique in a group of consecutively treated patients in our department. A review of the literature and the published results on local control and cosmesis is also described.

Purpose Few large European studies have evaluated long-term outcomes for permanent prostate brachytherapy (PPB) as monotherapy for clinically localized prostate cancer. The objective of the present study was to evaluate long-term survival in this patient profile. Methods and Materials Retrospective study of 700 patients who underwent transperineal ultrasound-guided iodine-125 PPB (145 Gy) between January 2000 and July 2012. Median age was 64.8 years (range, 35–79). Most patients (638 of 700; 91%) had low-risk disease (D'Amico criteria). Eighty-five patients (12%) received hormonal treatment. Overall survival, cause-specific survival, and biochemical relapse–free survival were calculated and estimated using actuarial and Kaplan–Meier methods. Differences between groups were assessed using the log-rank test. Results Median followup was 63 months (range, 6–164). At 5- and 10-year followup, respectively, overall survival was 94% (95% confidence interval [CI], 92–96) and 84% (95% CI, 78–90); cause-specific survival was 100% and 97% (95% CI, 95–99); and biochemical relapse–free survival was 95% (95% CI, 93–97) and 85% (95% CI, 79–91). Conclusions The long-term results presented in this report confirm previous studies and provide additional support for the use of PPB in patients with favorable-risk prostate cancer. Seed brachytherapy provides excellent long-term results in this patient profile.

In this update, antiretroviral therapy (ART) is recommended for all patients infected by type 1 human immunodeficiency virus (HIV-1). The strength and grade of the recommendation varies with clinical circumstances, number of CD4 cells, comorbid conditions and prevention of transmission of HIV. The objective of ART is to achieve an undetectable plasma viral load. Initial ART should always comprise a combination of 3 drugs, including 2 nucleoside reverse transcriptase inhibitors and a third drug from a different family (non-nucleoside reverse transcriptase inhibitor, protease inhibitor, or integrase inhibitor). This update presents the causes and criteria for switching ART in patients with undetectable plasma viral load and in cases of virological failure. An update is also provided for the specific criteria for ART in special situations (acute infection, HIV-2 infection, and pregnancy) and with comorbid conditions (tuberculosis or other opportunistic infections, kidney disease, liver disease, and cancer). (C) 2014 Elsevier Espana, S.L.U. and Sociedad Espanola de Enfermedades Infecciosas y Microbiologia Clinica. All rights reserved.

K-v channels detect changes in the membrane potential via their voltage-sensing domains (VSDs) that control the status of the S6 bundle crossing (BC) gate. The movement of the VSDs results in a transfer of the S4 gating charges across the cell membrane but only the last 10-20% of the total gating charge movement is associated with BC gate opening, which involves cooperative transition(s) in the subunits. Substituting the proline residue P475 in the S6 of the Shaker channel by a glycine or alanine causes a considerable shift in the voltage-dependence of the cooperative transition(s) of BC gate opening, effectively isolating the late gating charge component from the other gating charge that originates from earlier VSD movements. Interestingly, both mutations also abolished Shaker's sensitivity to 4-aminopyridine, which is a pharmacological tool to isolate the late gating charge component. The alanine substitution (that would promote a alpha-helical configuration compared to proline) resulted in the largest separation of both gating charge components; therefore, BC gate flexibility appears to be important for enabling the late cooperative step of channel opening.

Purpose To evaluate the efficacy and toxicity of external beam radiation therapy (EBRT) plus high-dose-rate brachytherapy (HDRB) as a boost in patients (pts) with intermediate or high-risk prostate cancer. Methods and materials From 2002 to July 2012, 377pts with a diagnosis of intermediate or high-risk prostate cancer were treated with EBRT plus HDRB. Median patient age was 66years (range, 41–86). Most patients (347pts; 92%) were classified as high-risk (stage T2c–T3, or PSA>20ng/mL, or GS⩾8), with 30 patients (8%) considered intermediate risk. All patients underwent EBRT at a prescribed dose of 60.0Gy (range, 45–70Gy) to the prostate and seminal vesicles. A total of 120pts (31%) received a dose of 46Gy (45–50Gy) to the true pelvis. All pts received a single-fraction 9Gy (9–15Gy) HDR boost. Most patients (353; 94%) were prescribed complete androgen deprivation therapy (ADT). Overall survival (OS), cause-specific survival (CSS), and biochemical relapse-free survival (BRFS) rates were calculated. In the case of BRFS, patients with n =106) were excluded to minimize the impact of ADT. Results The median follow-up for the entire sample was 50months (range, 12–126), with 5-year actuarial OS and CSS, respectively, of 88% (95% confidence interval [CI]: 84–92) and 98% (95% CI: 97–99). The 5-year BRFS was 91% (95% CI: 87–95) in the 271pts with ⩾26months (median, 60months) of follow-up. Late toxicity included grade 2 and 3 gastrointestinal toxicity in 17 (4.6%) and 6pts (1.6%), respectively, as well as grades 2 and 3 genitourinary toxicity in 46 (12.2%) and 3pts (0.8%), respectively. Conclusion These long-term outcomes confirm that EBRT plus a single-fraction HDRB boost provides good results in treatment-related toxicity and biochemical control. In addition to the excellent clinical results, this fractionation schedule reduces physician workload, treatment-related expenses, patient discomfort and risks associated with anaesthesia. We believe these findings support the use of single-fractionation boost techniques.

Background : Simplification of antiretroviral therapy (ART) may be an option for virologically suppressed patients for a variety of reasons. Etravirine (ETV) 400 mg qd has a good safety profile and retains activity against viruses resistant to nevirapine or efavirenz. Our objective was to evaluate the efficacy of ETV plus two nucleoside reverse transcriptase inhibitors (NRTIs) as a simplification strategy in treatment-experienced virologically suppressed individuals with prior episodes of virological failure (VF) and presence of genotypic resistance mutations (GRM). Methods : Eligible subjects were followed for ≥6 mo. Primary endpoint was proportion of patients remaining virologically suppressed using an ITT analysis. Genotypic sensitivity score (GSS) to new regimen was calculated according to Stanford resistance database. Results : Fourteen (10%) of 145 subjects switching to ETV+2NRTIs while virologically suppressed had a documented prior VF and presence of GRM and were included in the analysis. Median (range) number of previous episodes of VF to ART, NRTI-containing regimen, to a NNRTI-containing regimen and to a PI-containing regimen were 4 (1-6), 2 (1-5), 1 (0-2) and 1 (0-2) respectively. Median duration of virological suppression before switching therapy was 22.5 months (1-65). All patients switched from an effective PI-containing regimen (8 LPV/r, 5 ATV/r and 1 DRV/r) to a qd regimen with ETV 400 mg plus Truvada ® (n=12) or Kivexa ® (2). 11/14 patients (79%) remained virologically suppressed at ≥6 mo. All of them had a GSS >1.5 to the new regimen and none had resistance to etravirine. Conversely 3/14 (21%) developed a VF at 1, 3 and 6 months respectively. All these 3 patients had a GSS ≤1.5 to the new regimen and 2 of them intermediate resistance to ETV (Y181C). No side effects were reported. Conclusions : Our results suggest that ETV plus 2NRTI could be a good strategy for simplification in virologically suppressed patients despite previous episodes of VF if the GSS to the new regimen is ≥1.5 and ETV remains active. (Published: 11 November 2012) Citation: Abstracts of the Eleventh International Congress on Drug Therapy in HIV Infection Blanco J et al. Journal of the International AIDS Society 2012, 15 (Suppl 4):18379 http://www.jiasociety.org/index.php/jias/article/view/18379 | http://dx.doi.org/10.7448/IAS.15.6.18379

Background : Patients with a discordant response to cART, defined as persistent CD4+T-cell counts

Students in classrooms face challenges of which teachers and adults are either unaware or simply do not notice. Jonathan’s parents nor his teachers knew about the difficult situation Jonathan was experiencing with his classmates. Like so many parents and teachers, they did not have any reason to suspect that ten-year-old Jonathan was a victim of a cyber gang’s activities occurring right in his own living room and inside his classroom.

Stereotactic Body Radiation Therapy With Volumetric Modulated Arc Therapy and Flattening Filter-Free Beams in Lowor Intermediate-Risk Prostate Cancer: Early Experience and Quality of Life Assessment in Phase 1-2 Trial F. Ferrer, O. Garin, H.A. Letelier, R. De Blas, A. Boladeras, E. Garcia, E. Zardoya, R. Pineiro, A. Hervas, M. Castells, V. Macias, M. Galdeano, C. Gutierrez, M. Ventura, D. Najjari, E. Martinez, J.F. Suarez, C. Picon, J. Pera, and F. Guedea; Catalan Institute of Oncology, L’Hospitalet-Barcelona, Spain, Health Services Research Group IMIM (Hospital del Mar Research Institute), Barcelona, Spain, Escuela de Medicina, Universidad de Valparaiso, Valparaiso, Chile, Ramon y Cajal Hospital, Madrid, Spain, Bellvitge Hospital, L’Hospitalet-Barcelona, Spain, Salamanca Hospital, Salamanca, Spain, University of Barcelona, L’Hospitalet-Barcelona, Spain

Background: Administration of antiretroviral therapy (ART) once daily is creating extraordinary interest among the members of the scientific community and also among those who receive the therapy. However, in clinical practice, some doubts remains about its use. Objectives: This document examines the characteristics and possibilities of treatment administered once daily. Methods: Consensus of 248 Spanish experts in the field. Results: Once-daily dosing is considered an added value which could favour adherence and, therefore, efficacy, as well as the quality of life of certain patients, however, the objective of adequate adherence in the long term is often difficult to achieve regardless of the treatment used. In theory, any patient can receive once-daily therapy, although some patients could particularly benefit from it, e.g. those with unfavourable social or personal circumstances, including drug users, patients whose treatment must be supervised, patients receiving multiple medications, or those who need rescue therapy after multiple treatment failures. At present, it is possible to design once-daily ART using some of the combinations of drugs considered as first-choice in national and international recommendations for antiretroviral therapy, but the options are still limited. The marketing of new drugs with this characteristic could allow us to increase the number and types of patient who can benefit from once-daily regimens, including those patients who need rescue therapy. Conclusions: Once-daily ART is a good alternative to regimens administered several times each day when a potent combination of active drugs is available.

Toluene is a commonly used organic solvent in commercial products and is sometimes abused as an inhalative hallucinogen, causing arrythmogenic toxicity. At a molecular level we investigated whether a hypothetical interaction model could be devised for the reported myo- and cardiotoxic effects of toluene. Three lines of computed evidence support our hypothesis on the interaction mechanism: (i) Toluene binds at the local anesthetic binding site (LABS), on the wild type (WT) but not on its F1579A mutation, confi rming our experimental fi ndings that it inhibits only the WT of skeletal muscle or cardiac isoforms (Na v 1.4 or 1.5). (ii) Typically for small alkylaryl moiety, multiple binding modes were detected during docking. Toluene is trapped in the tryptophane-rich area at the extracellular vestibule by hydrophobic interaction, mainly π-π stacking, or bound to the LABS with equal binding strength and number of solved poses, mostly by edge-to-face contacts. (iii) The computed loss of toluene binding at the LABS on the mutant model parallels clearly the observed loss of toluene effects on Na v 1.4. Moreover, we inspected the complete primary sequences with the omitted loops in the 3D models to identify the possible interacting amino acids among the 16% nonidentical ones, and thus confi rmed the observed toxicity effects. + channel, Na v 1.4 isoform, Na v 1.5 isoform, in-silico simulation, cardiotoxicity

Kv channel subunits consist of 6 transmembrane segments (S1-S6) whereby the S1 through S4 segments assemble into a voltage sensing domain (VSD) that detects the membrane electric field. The positively charged S4 segment forms the main component of the VSD and undergoes the largest reorientations upon a membrane de- or hyperpolarization, generating a transient gating current. The S1-S3 segments surround the S4 and facilitate the latter's movement across the hydrophobic plasma-membrane. A positive (lysine) and negative (aspartate) charge substitution scan at the extracellular end of the S1 segment in the Shaker-type Kv1.5 channel indicated that this region is sufficiently close to the S4 segment such that it modulates the local membrane electric field. At positions E268, E272, F273 and E276 a charge substitution or charge introduction exerted a surface charge effect and shifted the voltage dependence of channel opening accordingly. Surprisingly, these residues, which modulated the electric field, did not face the S4 in a predicted 3D structure of the Kv1.5 channel in the open state (homology model based on the crystal structure of the Kv2.1/Kv1.2 chimera). This suggests that the introduced charges affect the electrical field around the S4 segment in the closed state only. In conclusion, residues at the top of the S1 segment can state-dependently offset (polarize) the electric field sensed by the S4 segment, supporting that both segments are in close proximity. (This research was supported by fellowship CONACyT #203936 to EMM & grant FWO-G.0449.11N to DJS.)

Voltage-gated K+ (Kv) channels exist as tetramers of α-subunits that contain six transmembrane segments (S1-S6). The S5-S6 segments assemble into the ion permeation pathway that is surrounded by four voltage-sensing domains (VSD). Upon a membrane depolarization the VSD's move independently to the ‘pre-activated state’, and subsequently in a concerted way to the activated state that results in channel opening. It has been reported that 1-alkanols, such as 1-Butanol, inhibit Kv channels by binding to the S4-S5 linker and the bottom part of S6 (S6c), suggesting that they affect the gating machinery. Recently, we demonstrated that the polycyclic-ether toxin gambierol -that most likely binds to S6c outside the permeation pathway- impairs VSD movement in Kv3.1 channels. To determine whether 1-Butanol immobilizes the VSD similarly, we analyzed gating currents of Shaker-W434F channels expressed in HEK-293 cells. Determining WT Shaker's affinity for 1-Butanol based on the fraction of ionic current block yielded an IC50 value of ∼50 mM. Concentrations that yielded full current block reduced charge movement in Shaker-W434F by at least 50%. Based on the loss in gating charge movement an IC50 value of ∼260 mM was obtained which in a model with 4 identical binding sites fits the IC50 value of 50 mM obtained from ionic current inhibition. Kinetic analysis showed that 1-Butanol accelerated the deactivating gating currents similar to 4-AP indicating that the final concerted step could not be passed. However, this final concerted step carries only 5% of the total charge and 1-Butanol reduced charge movement by at least 50%. These data suggest that the mechanism of 1-Butanol is reminiscent to that of gambierol and stabilizes an early/deep closed state. (supported by fellowship CONACyT #176137 to EMM & grant FWO-G0433.12N to DJS)

4559 Background: Sunitinib is a tyrosin kinase inhibitor with proven efficacy in renal clear cell carcinoma (RCCC). However properly validated molecular predictors of response or toxicity are still lacking. This study aims to identify such genetic markers focusing on the pharmacokinetics and pharmacodynamics pathways of the drug. Methods: An observational prospective study involving 15 centers of the Spanish Oncology Genitourinary Group (SOGUG) was designed to collect DNA from RCCC sunitinib-treated patients. Eligibility criteria included patients with locally, advanced or metastatic clear renal cell carcinoma treated with sunitinib in a daily practice setting and no prior systemic treatment (neither chemotherapy nor immunotherapy). A total of 15 key polymorphisms in 8 genes involved in the pharmacokinetics (CYP3A4, CYP3A5, ABCB1 and ABCG2) and pharmacodynamics (VEGF, VEGFR2, VEGFR3 and PDGFRa) of the drug were selected to perform a genotype-phenotype analysis. Results: From February 2008 trough December ...

The efficacy of raltegravir (RAL) in salvage regimens without protease inhibitors (PI) has not been evaluated in randomized trials, and information about its efficacy and reasons for its initiation in cohort studies has received scant attention. In some particular scenarios physicians may be forced to use RAL without PI due to advanced protease resistance, toxicity or patient refusal. Supplement: Abstracts of the Tenth International Congress on Drug Therapy in HIV Infection http://www.biomedcentral.com/content/pdf/1758-2652-13-S4-info.pdf Conference: Tenth International Congress on Drug Therapy in HIV Infection 7-11 November 2010 Glasgow, UK (Published: 8 November 2010) doi:10.1186/1758-2652-13-S4-P35 Cite this article as: Llibre et al.: Reasons for using and efficacy of raltegravir in salvage regimens without protease inhibitors in clinical practice. Journal of the International AIDS Society 2010 13(Suppl 4):P35. Full text: PubMed Central: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3113037/