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The Philippine Department of Education (DepEd) reiterated the need to conduct class observations to help ensure the delivery of quality basic education to all learners. It developed the Results-Based Performance Management System (RPMS) Manual for Teachers and School Heads, aligned with the Philippine Professional Standards for Teachers (PPST). The manual provides school heads and other raters with a detailed reference to help understand the tools and the different phases of assessment within the various cycles of RPMS, ensuring that mechanisms are in place to support teacher performance (DepEd, 2018). It is on this premise that this study is conducted. Primarily, it aimed to ascertain the elementary teachers' views on the conduct of the class observations. Likewise, it also identified the factors necessary for the smooth conduct of the class observations. This study utilized the case study research design. It involved eighteen (18) elementary teacher participants and three (3) school principals, utilizing a purposive sampling design. The interview guide was used to gather the data, which was analyzed using the Collaizzi's method. The study found that the elementary teachers' views are characterized as systemic and observer expertise. The factors necessary for the smooth conduct of the class observations are: (1) observe honesty, confidentiality, and collegiality; (2) provide actionable feedback; and (3) support productive collaboration among teachers. Future researchers may duplicate this study on a national scale to validate the study's findings. [ABSTRACT FROM AUTHOR]

Purpose: The COVID-19 pandemic began in early 2020 and became a global health crisis with devastating impacts. This scoping review maps the key findings of research about the pandemic that has operationalized intersectional research methods around the world. It also tracks how these studies have engaged with methodological tenets of oppression, comparison, relationality, complexity, and deconstruction., Methods: Our search resulted in 14,487 articles, 5164 of which were duplicates, and 9297 studies that did not meet the inclusion criteria were excluded. In total, 14 articles were included in this review. We used thematic analysis to analyse themes within this work and Misra et al. (2021) intersectional research framework to analyse the uptake of intersectional methods within such studies., Results: The research related to the COVID-19 pandemic globally is paying attention to issues around the financial impacts of the pandemic, discrimination, gendered impacts, impacts of and on social ties, and implications for mental health. We also found strong uptake of centring research in the context of oppression, but less attention is being paid to comparison, relationality, complexity, and deconstruction., Conclusions: Our findings show the importance of intersectional research within public health policy formation, as well as room for greater rigour in the use of intersectional methods.

Intensive chemotherapy (IC) is commonly used to achieve remission in patients with acute myeloid leukemia (AML). Venetoclax plus azacitidine (VEN-AZA) is FDA-approved to treat patients with AML aged ≥ 75 years or who are ineligible for IC. This retrospective analysis used de-identified electronic health records from the US-based Flatiron Health database from patients diagnosed 11/21/2018 to 10/31/2021 to compare treatment outcomes with VEN-AZA vs. IC. Patients were 1:1 propensity score-matched ([Formula: see text]). Assessments included rates of complete remission (CR) and hematopoietic stem cell transplant (HSCT), overall survival (OS), and relapse-free survival (RFS). CR and HSCT rates were higher with IC than with VEN-AZA (60.9% vs. 44.2% [P = 0.006] and 18.1% vs. 8.0% [P = 0.012], respectively). Median OS was 17.7 months in patients treated with IC and 11.3 months with VEN-AZA without censoring (P = 0.278) and 13.7 vs. 10.6 months, respectively, with censoring at HSCT (P = 0.584). Median RFS was 12.0 months in patients treated with IC vs. 9.5 months with VEN-AZA without censoring (P = 0.431) and 6.4 vs. 7.4 months, respectively, with censoring at HSCT (P = 0.444). No OS or RFS differences observed between the two arms reached statistical significance. Randomized controlled trials comparing the two approaches are warranted, as are novel approaches to reduce relapse rates following CR., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To describe real-world treatment patterns and outcomes among adult patients with myelodysplastic syndromes (MDS) treated with hypomethylating agents (HMA), patients were identified in the SEER-Medicare database (01/2006-12/2016); 3,046 patients with MDS treated with HMA were included. An algorithm was developed to categorize patients into MDS risk groups: the majority of patients were classified as Higher-risk (70.9%), 8.0% as Intermediate-risk, and 21.1% as Unknown-risk. Overall, 77.4% of patients initiated azacitidine and 22.6% decitabine; they received an average of 5.1 index-HMA cycles, of which 90.9% were complete with a median cycle duration of 28 days. Median survival was 11.6, 18.4, and 19.1 months for the Higher-risk, Intermediate-risk, and Unknown-risk groups, respectively. Median time-to-AML transformation was 19.3 months for the Higher-risk group and 50.4 months for the Intermediate-risk group (not reached for Unknown-risk). Data highlight the unmet medical needs of patients with MDS treated with HMA, particularly for the Higher-risk MDS group.

We evaluated standard-of-care (SOC) treatment with or without midostaurin to prevent relapse following allogeneic hematopoietic stem cell transplant (alloHSCT) in patients with acute myeloid leukemia (AML) harboring internal tandem duplication (ITD) in FLT3. Adults (aged 18-70 years) who received alloHSCT in first complete remission, had achieved hematologic recovery, and were transfusion independent were randomized to receive SOC with or without midostaurin (50 mg twice daily) continuously in twelve 4-week cycles. The primary endpoint was relapse-free survival (RFS) 18 months post-alloHSCT. Sixty patients were randomized (30/arm); 30 completed all 12 cycles (midostaurin + SOC, n = 16; SOC, n = 14). The estimated 18-month RFS (95% CI) was 89% (69-96%) in the midostaurin arm and 76% (54-88%) in the SOC arm (hazard ratio, 0.46 [95% CI, 0.12-1.86]; P = 0.27); estimated relapse rates were 11% and 24%, respectively. Inhibition of FLT3 phosphorylation to <70% of baseline (achieved by 50% of midostaurin-treated patients) was associated with improved RFS. The most common serious adverse events were diarrhea, nausea, and vomiting. Rates of graft-vs-host disease were similar between both arms (midostaurin + SOC, 70%; SOC, 73%). The addition of midostaurin maintenance therapy following alloHSCT may provide clinical benefit in some patients with FLT3-ITD AML. (ClinicalTrials.gov identifier: NCT01883362).

Aims: To describe healthcare resource utilization (HRU) and costs in patients with myelodysplastic syndromes (MDS) treated with hypomethylating agents (HMA) based on HMA-treatment response., Materials and Methods: SEER-Medicare data (January 2006-December 2016) were used to identify adults diagnosed with MDS (SEER: January 2009-December 2015) initiated on HMA (index date). HMA-treatment success (indicators: ≥7 HMA cycles, stem cell transplantation, and transfusion independence) or failure (indicators: acute myeloid leukemia [AML], AML-like treatment, and death) was determined using a claim-based algorithm. HRU and costs were assessed from the index date to 1-year post-index, overall and stratified by HMA-treatment success or failure. Among patients with HMA-treatment failure, HRU and costs were also assessed from failure to 1-year post-failure., Results: The study included 3,046 patients (mean age: 77.4 years; females: 36.8%). Rates of HMA-treatment success and failure were 44.4% and 76.2%, respectively (20.6% had HMA-treatment success then failure). Overall, patients had 15.2 inpatient admissions per-100-patients-per-month (median follow-up: 5.9 months). Patients with HMA-treatment success had 7.5 inpatient admissions per-100-patients-per-month (median follow-up: 12.0 months), while those with HMA-treatment failure had 20.4 and 35.3 admissions per-100-patients-per-month pre- and post-HMA-treatment failure, respectively (median follow-up: 4.3 and 1.8 months, pre- and post-HMA-treatment failure, respectively). Mean total healthcare costs were $12,494 per-patient-per-month overall, $8,069 per-patient-per-month among patients with HMA-treatment success, and $13,809 and $19,242 per-patient-per-month pre- and post-HMA-treatment failure, respectively. Outpatient costs (68.3%) were the main contributor of total healthcare costs overall, while inpatient costs (80.3%) were the main cost driver post-HMA-treatment failure., Limitations: Without available laboratory test results, clinical indicators observed in claims were used to assess HMA-treatment response., Conclusions: Over 75% of patients with MDS failed HMA-treatment within 6 months of initiation and were observed with more inpatient admissions than those with HMA-treatment success, translating into substantially higher healthcare costs. HMA-treatment failure results in an important economic burden in MDS patients.

Approval of midostaurin, a multikinase inhibitor, in combination with chemotherapy for the treatment of adults with newly diagnosed FLT3 mutation-positive acute myeloid leukemia, was based on the phase 3 RATIFY trial results. RADIUS-X (NCT02624570) was an expanded access program providing access to midostaurin during regulatory review and extending the understanding of the safety and tolerability of midostaurin. Patients aged ≥18 years received midostaurin with 1-2 cycles of induction therapy (cytarabine plus daunorubicin or idarubicin) and ≤4 cycles of high-dose cytarabine consolidation chemotherapy or as single-agent maintenance therapy. The study enrolled 103 patients. No new safety events were observed; toxicities were not influenced by age, anthracycline choice, or coadministration of CYP3A4 inhibitors. The most common adverse events (AEs) were febrile neutropenia, nausea, and diarrhea. During maintenance, 46% of patients reported AEs. Midostaurin demonstrated a manageable safety profile and was associated with high transplant and low on-treatment relapse rates.

Introduction: Identification of cytogenetic and molecular abnormalities has become vital for the appropriate treatment of acute myeloid leukemia (AML). One of the most common molecular alterations in AML is the constitutive activation by internal tandem duplication of FMS-like tyrosine kinase 3 (FLT3)., Methods: This observational, retrospective, cohort study at the Huntsman Cancer Institute (HCI) had two time periods: 1) a historical pre-midostaurin time period which consisted of the FLT3 mutated (FLT3m) and FLT3 wild type (FLT3wt) cohorts from January 1, 2007, to December 31, 2016, and 2) a post-midostaurin cohort which consisted of the FLT3 mutated midostaurin-user cohort (early mido) from May 01, 2017 to December 31, 2018., Results: In total, 39 patients were included in the FLT3m cohort, 61 in the FLT3wt cohort, and seven in the early mido cohort. FLT3m patients spent fewer days in the hospital during the first consolidation regimen and received fewer consolidation cycles compared to FLT3wt patients. Overall survival (OS) was similar between FLT3m and FLT3wt patients. For patients without hematopoietic stem cell transplant, OS was significantly shorter for FLT3m patients compared to FLT3wt patients. Mean AML related inpatient charges and physician charges for FLT3m patients were significantly higher than FLT3wt patients., Conclusion: The FLT3 mutation is historically associated with a shorter time to transplant and increased total health care charges. More information is needed to evaluate the real-world treatment strategies for FLT3-mutated patients in the presence of FLT3 inhibitors and the impact of these treatment strategies on clinical and economic outcomes., (Copyright © 2019. Published by Elsevier Ltd.)

Modulation by neuropeptides enhances several functions of acid-sensing ion channels (ASICs), such as pain sensation and acid-induced neuronal injury. The acid-induced opening of ASICs is transient, because of a rapid desensitization. Neuropeptides containing an Arg-Phe-amide motif affect ASIC desensitization and allow continuous activity of ASICs. In spite of the importance of the sustained ASIC activity during prolonged acidification, the molecular mechanisms of ASIC modulation by neuropeptides is only poorly understood. To identify the FRRFa (Phe-Arg-Arg-Phe-amide) binding site on ASIC1a, we carried out an in silico docking analysis and verified functionally the docking predictions. The docking experiments indicated three possible binding pockets, located (1) in the acidic pocket between the thumb, finger, β-ball and palm domains, (2) in a pocket at the bottom of the thumb domain, and (3) in the central vestibule along with the connected side cavities. Functional measurements of mutant ASIC1a confirmed the importance of residues of the lower palm, which encloses the central vestibule and its side cavities, for the FRRFa effects. The combined docking and functional experiments strongly suggest that FRRFa binds to the central vestibule and its side cavities to change ASIC desensitization.

Objectives: The aim of this study was to assess the cost effectiveness of midostaurin + cytarabine + daunorubicin (midostaurin arm) versus placebo + cytarabine + daunorubicin (placebo arm) in the treatment of adult patients with newly diagnosed FLT3-mutated acute myeloid leukemia (AML) who are eligible for standard cytarabine + daunorubicin chemotherapy, from a US third-party payer perspective., Methods: A lifetime partitioned survival model with four health states (active disease, complete remission [CR], relapse, and death) was constructed. Efficacy inputs (time to CR or death, time to relapse or death, and overall survival) were estimated using data from the RATIFY trial (NCT00651261). Costs (inflated to 2016 US dollars) included treatment, drug monitoring, stem cell transplantation (SCT), adverse events costs, and medical costs associated with health states. Incremental costs per quality-adjusted life-year (QALY) and life-year (LY) gained were estimated. Deterministic (DSA) and probabilistic sensitivity analyses (and PSA) were performed to assess model robustness., Results: In the base case, patients in the midostaurin arm incurred higher total direct costs over a lifetime compared with the placebo arm ($4,043,470 vs. $3,959,741), resulting in an incremental cost of $83,729; however, the midostaurin arm had better effectiveness, with 1.59 more LYs and 1.37 more QALYs. These led to a base-case incremental cost-effectiveness ratio (ICER) of $52,596 per LY, or $61,167 per QALY. Results were robust in the DSA. In the PSA, the probability of the midostaurin arm being cost-effective compared with the placebo arm was 65.9%, at a willingness to pay of $150,000/QALY., Conclusions: This analysis suggests that midostaurin is a cost-effective treatment for adult patients with newly diagnosed FLT3-mutated AML, from a US third-party payer perspective.

Background: Preference valuations of health status are essential in health technology and economic appraisal. This study estimated utilities for treatment-related health states of acute myeloid leukemia (AML) and disutilities of severe adverse events (SAEs) using a representative sample of adults from the general population in the United States (US)., Methods: Treatment-related AML health states, defined based on literature and interviews with clinicians, included complete remission (CR), no CR, relapse, stem cell transplant (SCT), and post SCT short-term recovery. Six attributes with varying levels, including fever, lack of energy, problems with daily function, anxiety/depression, blood transfusions, and hospitalization, were used to define health states. An online survey using discrete choice experiment methodology was designed to capture preferences for health status scenarios including the identified attributes and key grade 3/4 chemotherapy-related SAEs. Health state utilities and SAE disutilities were generated from a conditional logistic regression with generalized estimating equations., Results: Of the 300 survey participants, the demographic distributions were within a 3% margin of those in the 2010 US Census. CR had the highest utility value (0.875), followed by post-SCT short-term recovery (0.398), relapse (0.355), no CR (0.262), and SCT (0.158). Of the SAEs, serious infection had the highest decline in utility (0.218), followed by severe diarrhea (0.176), abnormally low blood cell counts (0.100), and severe redness/skin peeling (0.060)., Conclusions: AML and treatments can result in reduced quality of life and impaired ability to perform daily activities. Findings of this study underline the value that society places on treatment-related AML health states and SAEs.

Objective: To describe the setting, duration, and costs of induction and consolidation chemotherapy for adults with newly-diagnosed acute myeloid leukemia (AML), who are candidates for standard induction chemotherapy, in the US., Methods: Adults newly-diagnosed with AML who received standard induction chemotherapy in an inpatient setting were identified from the Truven Health Analytics MarketScan (2006-2015) and SEER-Medicare (2007-2011) databases. Patients were observed from induction therapy start to the first of hematopoietic stem cell transplant, 180 days after induction discharge, health plan enrollment/data availability end, or death. Induction and consolidation chemotherapy were identified using Diagnosis-Related Group codes (chemotherapy with acute leukemia) or procedure codes for AML chemotherapy administration. AML treatment episode setting (inpatient or outpatient), duration, and costs (2015 USD, payers' perspective) were described for commercially insured patients and Medicare beneficiaries., Results: In total, 459 commercially insured patients and 563 Medicare beneficiaries (mean age = 54 and 66 years; 53% and 54% male; respectively) were identified. For induction therapy, mean costs were $145,189 for commercially insured patients and $85,734 for Medicare beneficiaries, and median inpatient duration was 31 days (both). Following induction, 64% of commercially insured patients and 53% of Medicare beneficiaries had ≥1 consolidation cycle; 75% and 65% of consolidation cycles were in an inpatient setting, respectively. For consolidation cycles, in the inpatient setting, mean costs were $28,137 for commercially insured patients and $28,843 for Medicare beneficiaries, median cycle duration was 6 days (both); in the outpatient setting, mean costs were $11,271 for commercially insured patients and $5,803 Medicare beneficiaries, median duration was 5 days (both)., Limitations: Granular information on chemotherapy type administered was unavailable., Conclusions: This is the first exploratory study providing a complete picture of recent AML treatment patterns and management costs among commercially insured patients and Medicare beneficiaries. There is substantial heterogeneity in the management and costs of AML.

Acid-sensing ion channels (ASICs) are proton-activated Na + channels expressed in the nervous system, where they are involved in learning, fear behaviors, neurodegeneration, and pain sensation. In this work, we study the role in pH sensing of two regions of the ectodomain enriched in acidic residues: the acidic pocket, which faces the outside of the protein and is the binding site of several animal toxins, and the palm, a central channel domain. Using voltage clamp fluorometry, we find that the acidic pocket undergoes conformational changes during both activation and desensitization. Concurrently, we find that, although proton sensing in the acidic pocket is not required for channel function, it does contribute to both activation and desensitization. Furthermore, protonation-mimicking mutations of acidic residues in the palm induce a dramatic acceleration of desensitization followed by the appearance of a sustained current. In summary, this work describes the roles of potential pH sensors in two extracellular domains, and it proposes a model of acidification-induced conformational changes occurring in the acidic pocket of ASIC1a.

Reliable quantification of white matter hyperintensities of presumed vascular origin (WMHs) is increasingly needed, given the presence of these MRI findings in patients with several neurological and vascular disorders, as well as in elderly healthy subjects. We present BIANCA (Brain Intensity AbNormality Classification Algorithm), a fully automated, supervised method for WMH detection, based on the k-nearest neighbour (k-NN) algorithm. Relative to previous k-NN based segmentation methods, BIANCA offers different options for weighting the spatial information, local spatial intensity averaging, and different options for the choice of the number and location of the training points. BIANCA is multimodal and highly flexible so that the user can adapt the tool to their protocol and specific needs. We optimised and validated BIANCA on two datasets with different MRI protocols and patient populations (a "predominantly neurodegenerative" and a "predominantly vascular" cohort). BIANCA was first optimised on a subset of images for each dataset in terms of overlap and volumetric agreement with a manually segmented WMH mask. The correlation between the volumes extracted with BIANCA (using the optimised set of options), the volumes extracted from the manual masks and visual ratings showed that BIANCA is a valid alternative to manual segmentation. The optimised set of options was then applied to the whole cohorts and the resulting WMH volume estimates showed good correlations with visual ratings and with age. Finally, we performed a reproducibility test, to evaluate the robustness of BIANCA, and compared BIANCA performance against existing methods. Our findings suggest that BIANCA, which will be freely available as part of the FSL package, is a reliable method for automated WMH segmentation in large cross-sectional cohort studies., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: We have previously shown that increased resting-state functional magnetic resonance imaging (fMRI)-based functional connectivity (FC) within the frontal resting-state networks in Alzheimer's disease (AD) patients reflects residual, possibly compensatory, function. This suggests that symptomatic treatments should aim to enhance FC specifically in these networks., Methods: 18 patients with probable AD underwent brain MRI and neuropsychological assessment at baseline and after 12 weeks of treatment with donepezil. We tested if changes in cognitive performance after treatment correlated with changes in FC in resting-state networks known to be altered in AD., Results: We found increases in FC in the orbitofrontal network that correlated with cognitive improvement after treatment. The increased FC was greatest in patients who responded most to treatment., Conclusion: This 'proof of concept' study suggests that changes in network-specific FC might be a biomarker of pharmacological intervention efficacy in AD.

Today the management of resistant hypertension is a critical health problem: the main difficulty on this field is the discrimination of cases of poor therapeutic adherence from cases of real resistance. This gives rise to the need of high throughput and reliable quantification methods for the Therapeutic Drug Monitoring (TDM) of antihypertensive drugs. The aim of this work was the development and validation of a UHPLC-Tandem mass spectrometry assay for this application and its use in plasma from patients with resistant hypertension. The novelty of this method resides in the ability to simultaneously quantify a wide panel of antihypertensive drugs: amlodipine, atenolol, clonidine, chlortalidone, doxazosin, hydrochlorothiazide, nifedipine, olmesartan, ramipril and telmisartan. Moreover, this method stands out for its simplicity and cheapness, resulting feasible for clinical routine. Both standards and quality controls were prepared in human plasma. After the addition of internal standard, each sample underwent protein precipitation with acetonitrile and was then dried. Extracts were resuspended in water:acetonitrile 90:10 (0.05% formic acid) and then injected into the chromatographic system. Chromatographic separation was performed on an Acquity(®) UPLC HSS T3 1.8μm 2.1×150mm column, with a gradient of water and acetonitrile, both added with 0.05% formic acid. Accuracy, intra-day and inter-day precision fitted FDA guidelines for all analytes, while matrix effects and recoveries resulted stable between samples for each analyte. Finally, we tested this method by monitoring plasma concentrations in 22 hypertensive patients with good results. This simple analytical method could represent a useful tool for the management of antihypertensive therapy., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The role of therapeutic drug monitoring (TDM) of entecavir (ETV) in the treatment of patients affected by chronic hepatitis B (CHB) has not yet been defined. Here we present an interim analysis regarding the role of ETV TDM in a prospective cohort of treatment-naïve patients with CHB who received this treatment. The results from 40 patients consecutively enrolled at our centre from 2010 to 2013 are described. The primary endpoint was the evaluation of the role of ETV plasma concentrations in the kinetics of hepatitis B virus (HBV) DNA decrease. Minimum ETV concentrations (Ctrough) were measured every month after the start of therapy for the first 3 months and then every 6 months. The main result of the pharmacokinetic analysis was the significant inverse correlation of ETV concentration after 1 month of treatment and HBV-DNA decrease after 3 months of treatment (r = -0.624; P <0.001). This correlation was also confirmed when stratifying patients on the basis of viral genotypes: A (r = -0.719; P = 0.003); C (r = -0.917; P = 0.007); and D (r = -0.760; P = 0.007). Possible explanations for this phenomenon could involve interpatient differences in liver conditions (tissue damage or inflammation) and/or genetic variability in specific drug transporters. Further investigations are needed to confirm these results quantifying ETV concentration in peripheral blood mononuclear cells as well as in a larger cohort., (Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.)

The introduction of MRI and positron emission tomography (PET) brain imaging has contributed significantly to the understanding of different dementia syndromes. Over the past 20 years these imaging techniques have been increasingly used for clinical characterisation and differential diagnosis, and to provide insight into the effects on functional capacity of the brain, patterns of spatial distribution of different dementia syndromes and their natural history and evolution over time. Brain imaging is also increasingly used in clinical trials, as part of inclusion criteria and/or as a surrogate outcome measure. Here we review all the relatively specific findings that can be identified with different MRI and PET techniques in each of the most frequent dementing disorders., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

To date five nucleoside analogs are used in the treatment of chronic hepatitis B: among these, entecavir is the most used. Nevertheless a few information about its distribution in tissues is currently known. Since the determination of entecavir disposition in the hepatocytes is impracticable because of its invasiveness, the quantification in an "easier-to-obtain" cellular model could be a good choice. In this work, we developed and validated an ultra performance liquid chromatography-tandem mass spectrometry assay based on an automated on-line SPE, to quantify entecavir concentrations in peripheral blood mononucleated cells (PBMCs), in both its phosphorylated and un-phosphorylated forms. To achieve this, each PBMC isolate was divided in two aliquots, one was treated with acid phosphatase to convert entecavir phosphorylated metabolites into free form, the other one was not-treated. Standards and quality controls were prepared in PBMCs, isolated from healthy donors, and underwent the same process. 20 μL of the resulting solutions were injected in the on-line SPE system. Thymidine was used as internal standard. Calibration curves fitted a linear model for entecavir levels in a range from 0.039 ng to 5 ng (mean r(2)=0.998). Accuracy, intra-day and inter-day precision of the method fitted FDA guidelines recommendations. Moreover, recovery was consistent and matrix effect resulted low and reproducible. We tested this method by monitoring entecavir concentrations in PBMCs from 28HBV mono-infected patients, confirming its reliability and suitability for the evaluation of intracellular entecavir penetration., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Acid-sensing ion channels (ASICs) are neuronal, voltage-independent Na(+) channels that are transiently activated by extracellular acidification. They are involved in pain sensation, the expression of fear, and in neurodegeneration after ischemic stroke. Our study investigates the role of extracellular subunit interactions in ASIC1a function. We identified two regions involved in critical intersubunit interactions. First, formation of an engineered disulfide bond between the palm and thumb domains leads to partial channel closure. Second, linking Glu-235 of a finger loop to either one of two different residues of the knuckle of a neighboring subunit opens the channel at physiological pH or disrupts its activity. This suggests that one finger-knuckle disulfide bond (E235C/K393C) sets the channel in an open state, whereas the other (E235C/Y389C) switches the channel to a non-conducting state. Voltage-clamp fluorometry experiments indicate that both the finger loop and the knuckle move away from the β-ball residue Trp-233 during acidification and subsequent desensitization. Together, these observations reveal that ASIC1a opening is accompanied by a distance increase between adjacent thumb and palm domains as well as a movement of Glu-235 relative to the knuckle helix. Our study identifies subunit interactions in the extracellular loop and shows that dynamic changes of these interactions are critical for normal ASIC function., (© 2015 by The American Society for Biochemistry and Molecular Biology, Inc.)

Background: Cerebrospinal fluid (CSF) levels assessment of Aβ1-42 and Tau proteins may be accurate diagnostic biomarkers for the differentiation of preclinical Alzheimer's disease (AD) from age-associated memory impairment, depression and other forms of dementia in patients with mild cognitive impairment (MCI). The aim of our study was to explore the utility of CSF biomarkers in combination with common cognitive markers as predictors for the risk of AD development, and other forms of dementia, and the time to conversion in community patients with MCI., Methods: A group of 71 MCI patients underwent neurological assessment, extended neuropsychological evaluation, routine blood tests, ApoE determination, and lumbar puncture to dose t-tau, p-tau181, Aβ1-42. We investigated baseline CSF and neuropsychological biomarker patterns according to groups stratified with later diagnoses of AD conversion (MCI-AD), other dementia (MCI-NAD) conversion, or clinical stability (sMCI)., Results: Baseline Aβ1-42 CSF levels were significantly lower in MCI-AD patients compared to both sMCI and MCI-NAD. Additionally, p-tau181 was higher in the MCI-AD group compared to sMCI. The MCI-AD subgroup analysis confirmed the role of Aβ1-42 in its predictive role of time to conversion: rapid converters had lower Aβ1-42 levels compared to slow converters. Logistic regression and survival analysis further supported the key predictive role of baseline Aβ1-42 for incipient AD and dementia-free survival., Conclusions: Our results confirm the key role of CSF biomarkers in predicting patient conversion from MCI to dementia. The study suggests that CSF biomarkers may also be reliable in a real world clinical setting.

In the present bed rest (BR) study, 23 volunteers were randomized into 3 subgroups: 60 d BR control (Ctr); BR with resistive exercise (RE; lower-limb load); and resistive vibration exercise (RVE; RE with superimposed vibration). The aim was to analyze by confocal and electron microscopy the effects of vibration on myofibril and filament integrity in soleus (Sol) and vastus lateralis (VL) muscle; differential proteomics of contractile, cytoskeletal, and costameric proteins (TN-C, ROCK1, and FAK); and expression of PGC1α and atrophy-related master genes MuRF1 and MuRF2. RVE (but not RE) preserved myofiber size and phenotype in Sol and VL by overexpressing MYBPC1 (42%, P ≤ 0.01), WDR1 (39%, P ≤ 0.01), sarcosin (84%, P ≤ 0.01), and CKM (20%, P ≤ 0.01) and prevented myofibrillar ultrastructural damage as detectable by MuRF1 expression. In Sol, cytoskeletal and contractile proteins were normalized by RVE, and TN-C increased (59%, P ≤ 0.01); the latter also with RE (108%, P ≤ 0.01). In VL, the outcomes of both RVE (acting on sarcosin and desmin) and RE (by way of troponinT-slow and MYL2) were similar. RVE appears to be a highly efficient countermeasure protocol against muscle atrophy and ultrastructural and molecular dysregulation induced by chronic disuse., (© FASEB.)

Acid-sensing ion channels (ASICs) are neuronal Na(+)-conducting channels activated by extracellular acidification. ASICs are involved in pain sensation, expression of fear, and neurodegeneration after ischemic stroke. Functional ASICs are composed of three identical or homologous subunits, whose extracellular part has a handlike structure. Currently, it is unclear how protonation of residues in extracellular domains controls ASIC activity. Knowledge of these mechanisms would allow a rational development of drugs acting on ASICs. Protonation may induce conformational changes that control the position of the channel gate. We used voltage-clamp fluorometry with fluorophores attached to residues in different domains of ASIC1a to detect conformational changes. Comparison of the timing of fluorescence and current signals identified residues involved in movements that preceded desensitization and may therefore be associated with channel opening or early steps leading to desensitization. Other residues participated in movements intimately linked to desensitization and recovery from desensitization. Fluorescence signals of all mutants were detected at more alkaline pH than ionic currents. Their midpoint of pH dependence was close to that of steady-state desensitization, whereas the steepness of the pH fluorescence relationship was closer to that of current activation. A sequence of movements was observed upon acidification, and its backward movements during recovery from desensitization occurred in the reverse order, indicating that the individual steps are interdependent. Furthermore, the fluorescence signal of some labeled residues in the finger domain was strongly quenched by a Trp residue in the neighboring β-ball domain. Upon channel activation, their fluorescence intensity increased, indicating that the finger moved away from the β ball. This extensive analysis of activity-dependent conformational changes in ASICs sheds new light on the mechanisms by which protonation controls ASIC activity.

The present investigation, the first in the field, was aimed at analyzing differentially, on individual samples, the effects of 55 days of horizontal bed rest, a model for microgravity, on myosin heavy and myosin light chain isoforms distribution (by SDS) and on the proteome (by 2-D DIGE and MS) in the vastus lateralis (VL), a mixed type II/I (∼50:50%) head of the quadriceps and in the calf soleus (SOL), a predominantly slow (∼35:65%) twitch muscle. Two separate studies were performed on six subjects without (BR) and six with resistive vibration exercise (RVE) countermeasures, respectively. Both VL and SOL underwent in BR decrements of ∼15% in cross-sectional area and of ∼22% in maximal torque that were prevented by RVE. Myosin heavy chain distribution showed increased type I and decreased type IIA in BR both in VL and in SOL, the opposite with RVE. A substantial downregulation of proteins involved in aerobic metabolism characterized both in SOL and VL in BR. RVE reversed the pattern more in VL than in SOL, whereas proteins involved in anaerobic glycolysis were upregulated. Proteins from the Z-disk region and from costamers were differently dysregulated during bed rest (both BR and RVE), particularly in VL.

Acute venous thromboembolism (VTE) is a common and potentially fatal complication that frequently occurs in cancer patients. Few data are currently available about the optimal management of this category of high-risk patients. In clinical practice, physicians have to deal with many problems related to cancer patients with acute VTE. For instance, cancer patients with deep vein thrombosis (DVT) are frequently admitted to the hospital since their high rate of recurrent thrombotic events and/or bleeding-related therapy; however, most of them would prefer alternatives to prolonged hospitalisation. Then, it is not clearly whether data coming from a non-cancer population (such as that regarding the use of D-dimer test and/or pre-test clinical probability [PCP]), can be reliable applied in cancer patients. Finally, scanty information is present on the feasibility of the "home-treatment program" for DVT in this category of high-risk patients. In our review we present data on a population of cancer patients evaluated at the Emergency Care in whom we have evaluated: 1) the diagnostic accuracy of PCP and D-dimer test; 2) the safety and efficacy of low molecular weight heparins (LMWH) as "protective anticoagulation" in case of deferred imaging for VTE and 3) the safety and efficacy of home treatment.

The kinetics of the phosphorolysis of 7-methylated guanosine analogues catalyzed by purine nucleoside phosphorylase has been analyzed to understand the use of this system as a "Pi mop" to remove Pi from solutions and as a spectroscopic assay for Pi at micromolar concentrations. An expression system was developed for the phosphorylase from Escherichia coli: this protein (subunit molecular mass 26 kDa) and one from a commercial source (29 kDa) were used in this study. Rates of >50 s-1 were obtained for the phosphorolysis at 30 degrees C, so that when the phosphorylase is coupled to the phosphatase being studied, rates of Pi release from the phosphatase can be measured close to this rate. The kinetic mechanism appears to obey the Michaelis-Menten model in the steady state with the bond cleavage rate limiting. Slow hydrolysis of ribose-1-phosphate to Pi catalyzed by the phosphorylase limits the efficiency of the Pi mop. To overcome this, phosphodeoxyribomutase was used to catalyze the conversion of ribose-1-phosphate to ribose-5-phosphate, enabling the Pi mop to remove large amounts of Pi quantitatively. Acyclovir diphosphate provides a simple method to switch off the Pi mop as it is a tight inhibitor (Kd 12 nM) of purine nucleoside phosphorylase., (Copyright 1998 Academic Press.)

The electrophoretic behavior of defined DNA and RNA oligonucleotide duplexes from 10 to 20 bp in length has been investigated as a function of salt conditions, gel concentration, and temperature. The RNA oligomers migrated much more slowly than the DNA oligomers of the same sequence under all conditions. From sedimentation equilibrium and velocity measurements, the apparent partial specific volume in 0.1 M KCI, 20 mM NaPi, pH 7, was determined as 0.56 +/- 0.015 ml g(-1) for DNA and 0.508 ml g(-1) for RNA. The translational friction coefficients were determined and compared with the values calculated for cylinders. Taking into account the shape factors, the solution density, and partial specific volumes, the effective degree of hydration was estimated as 0.8-1 g g(-1) DNA. There was no significant difference in the frictional coefficients of the DNA and RNA oligomers, indicating that the effective sizes of DNA and RNA are very similar in solution. The differential electrophoretic mobility of DNA and RNA must arise from the differences in interaction with counterions, which is probably a global property of the oligonucleotides.