Acute cardiovascular and muscular response to rowing ergometer exercise in artificial gravity - a pilot trial.

Prolonged immobilization and spaceflight cause cardiovascular and musculoskeletal deconditioning. Combining artificial gravity through short-arm centrifugation with rowing exercise may serve as a countermeasure. We aimed to compare the tolerability, muscle force production, cardiovascular response, and power output of rowing on a short-arm centrifuge and under terrestrial gravity. Twelve rowing athletes (4 women, aged 27.2 ± 7.4 years, height 179 ± 0.1 cm, mass 73.7 ± 9.4 kg) participated in two rowing sessions, spaced at least six weeks apart. One session used a short-arm centrifuge with +0.5 Gz, while the other inclined the rowing ergometer by 26.6° to mimic centrifugal loading. Participants started self-paced rowing at 30 W, increasing by 15 W every three minutes until exhaustion. We measured rowing performance, heart rate, blood pressure, ground reaction forces, leg muscle activation, and blood lactate concentration. Rowing on the centrifuge was well-tolerated without adverse events. No significant differences in heart rate, blood pressure, or blood lactate concentration were observed between conditions. Inclined rowing under artificial gravity resulted in lower power output (-33%, p < 0.001) compared to natural gravity, but produced higher mean and peak ground reaction forces (p < 0.0001) and increased leg muscle activation. Muscle activation and ground reaction forces varied with rotational direction. Rowing in artificial gravity shows promise as a strategy against cardiovascular and muscular deconditioning during long-term spaceflight, but further investigation is required to understand its long-term effects.

Functional analysis of chromatin-associated proteins in Sordaria macrospora reveals similar roles for RTT109 and ASF1 in development and DNA damage response.

We performed a functional analysis of two potential partners of ASF1, a highly conserved histone chaperone that plays a crucial role in the sexual development and DNA damage resistance in the ascomycete Sordaria macrospora. ASF1 is known to be involved in nucleosome assembly and disassembly, binding histones H3 and H4 during transcription, replication and DNA repair and has direct and indirect roles in histone recycling and modification as well as DNA methylation, acting as a chromatin modifier hub for a large network of chromatin-associated proteins. Here, we functionally characterized two of these proteins, RTT109 and CHK2. RTT109 is a fungal-specific histone acetyltransferase, while CHK2 is an ortholog to PRD-4, a checkpoint kinase of Neurospora crassa that performs similar cell cycle checkpoint functions as yeast RAD53. Through the generation and characterization of deletion mutants, we discovered striking similarities between RTT109 and ASF1 in terms of their contributions to sexual development, histone acetylation, and protection against DNA damage. Phenotypic observations revealed a developmental arrest at the same stage in Δrtt109 and Δasf1 strains, accompanied by a loss of H3K56 acetylation, as detected by western blot analysis. Deletion mutants of rtt109 and asf1 are sensitive to the DNA damaging agent methyl methanesulfonate, but not hydroxyurea. In contrast, chk2 mutants are fertile and resistant to methyl methanesulfonate, but not hydroxyurea. Our findings suggest a close functional association between ASF1 and RTT109 in the context of development, histone modification, and DNA damage response, while indicating a role for CHK2 in separate pathways of the DNA damage response.

Histone binding of ASF1 is required for fruiting body development but not for genome stability in the filamentous fungus Sordaria macrospora.

IMPORTANCE: Histone chaperones are proteins that are involved in nucleosome assembly and disassembly and can therefore influence all DNA-dependent processes including transcription, DNA replication, and repair. ASF1 is a histone chaperone that is conserved throughout eukaryotes. In contrast to most other multicellular organisms, a deletion mutant of asf1 in the fungus Sordaria macrospora is viable; however, the mutant is sterile. In this study, we could show that the histone-binding ability of ASF1 is required for fertility in S. macrospora, whereas the function of ASF1 in maintenance of genome stability does not require histone binding. We also showed that the histone modifications H3K27me3 and H3K56ac are misregulated in the Δasf1 mutant. Furthermore, we identified a large duplication on chromosome 2 of the mutant strain that is genetically linked to the Δasf1 allele present on chromosome 6, suggesting that viability of the mutant might depend on the presence of the duplicated region.

Functional characterization of the developmental genes asm2, asm3, and spt3 required for fruiting body formation in the filamentous ascomycete Sordaria macrospora.

The formation of fruiting bodies is one of the most complex developmental processes in filamentous ascomycetes. It requires the development of sexual structures that give rise to meiosporangia (asci) and meiotic spores (ascospores) as well as surrounding structures for protection and dispersal of the spores. Previous studies have shown that these developmental processes are accompanied by significant changes of the transcriptome, and comparative transcriptomics of different fungi as well as the analysis of transcriptome changes in developmental mutants have aided in the identification of differentially regulated genes that are themselves involved in regulating fruiting body development. In previous analyses, we used transcriptomics to identify the genes asm2 and spt3, which result in developmental phenotypes when deleted in Sordaria macrospora. In this study, we identified another gene, asm3, required for fruiting body formation, and performed transcriptomics analyses of Δasm2, Δasm3, and Δspt3. Deletion of spt3, which encodes a subunit of the SAGA complex, results in a block at an early stage of development and drastic changes in the transcriptome. Deletion mutants of asm2 and asm3 are able to form fruiting bodies, but have defects in ascospore maturation. Transcriptomics analysis of fruiting bodies revealed a large overlap in differentially regulated genes in Δasm2 and Δasm3 compared to the wild type. Analysis of nuclear distribution during ascus development showed that both mutants undergo meiosis and postmeiotic divisions, suggesting that the transcriptomic and morphological changes might be related to defects in the morphogenesis of structural features of the developing asci and ascospores.

Comparative Genomics and Transcriptomics To Analyze Fruiting Body Development in Filamentous Ascomycetes.

Many filamentous ascomycetes develop three-dimensional fruiting bodies for production and dispersal of sexual spores. Fruiting bodies are among the most complex structures differentiated by ascomycetes; however, the molecular mechanisms underlying this process are insufficiently understood. Previous comparative transcriptomics analyses of fruiting body development in different ascomycetes suggested that there might be a core set of genes that are transcriptionally regulated in a similar manner across species. Conserved patterns of gene expression can be indicative of functional relevance, and therefore such a set of genes might constitute promising candidates for functional analyses. In this study, we have sequenced the genome of the Pezizomycete Ascodesmis nigricans, and performed comparative transcriptomics of developing fruiting bodies of this fungus, the Pezizomycete Pyronema confluens, and the Sordariomycete Sordaria macrospora With only 27 Mb, the A. nigricans genome is the smallest Pezizomycete genome sequenced to date. Comparative transcriptomics indicated that gene expression patterns in developing fruiting bodies of the three species are more similar to each other than to nonsexual hyphae of the same species. An analysis of 83 genes that are upregulated only during fruiting body development in all three species revealed 23 genes encoding proteins with predicted roles in vesicle transport, the endomembrane system, or transport across membranes, and 13 genes encoding proteins with predicted roles in chromatin organization or the regulation of gene expression. Among four genes chosen for functional analysis by deletion in S. macrospora, three were shown to be involved in fruiting body formation, including two predicted chromatin modifier genes.

Immediate outcome indicators in perioperative care: a controlled intervention study on quality improvement in hospitals in Tanzania.

INTRODUCTION: Outcome assessment is the standard for evaluating the quality of health services worldwide. In this study, outcome has been divided into immediate and final outcome. Aim was to compare an intervention hospital with a Continuous Quality Improvement approach to a control group using benchmark assessments of immediate outcome indicators in surgical care. Results were compared to final outcome indicators. METHOD: Surgical care quality in six hospitals in Tanzania was assessed from 2006-2011, using the Hospital Performance Assessment Tool. Independent observers assessed structural, process and outcome quality using checklists based on evidence-based guidelines. The number of surgical key procedures over the benchmark of 80% was compared between the intervention hospital and the control group. Results were compared to Case Fatality Rates. RESULTS: In the intervention hospital, in 2006, two of nine key procedures reached the benchmark, one in 2009, and four in 2011. In the control group, one of nine key procedures reached the benchmark in 2006, one in 2009, and none in 2011. Case Fatality Rate for all in-patients in the intervention hospital was 5.5% (n = 12,530) in 2006, 3.5% (n = 21,114) in 2009 and 4.6% (n = 18,840) in 2011. In the control group it was 3.1% (n = 17,827) in 2006, 4.2% (n = 13,632) in 2009 and 3.8% (n = 17,059) in 2011. DISCUSSION: Results demonstrated that quality assurance improved performance levels in both groups. After the introduction of Continuous Quality Improvement, performance levels improved further in the intervention hospital while quality in the district hospital did not. Immediate outcome indicators appeared to be a better steering tool for quality improvement compared to final outcome indicators. Immediate outcome indicators revealed a need for improvement in pre- and postoperative care. CONCLUSION: Quality assurance programs based on immediate outcome indicators can be effective if embedded in Continuous Quality Improvement. Nevertheless, final outcome indicators cannot be neglected.

[A standardised German translation of the STAndards for Reporting of Diagnostic accuracy studies (STARD statement)*: Methodological aspects]. / Eine standardisierte Übersetzung der STAndards for Reporting of Diagnostic accuracy studies (STARD Statement) in Deutsch: Methodische Aspekte.

BACKGROUND: In order to be comprehensible and comparable scientific data should be reported according to a certain standard. One example is the 'STAndards for Reporting of Diagnostic Accuracy (STARD) Statement', a 25-item checklist for the appropriate conduct and reporting of diagnostic studies. Usually such scientific standards are published in English. The International Society for Pharmacoeconomics and Outcome Research (ISPOR) has developed guidelines for the translation and cultural adaptation of written medical instruments. The aim was to apply these ISPOR criteria to the German translation of the STARD Statement in order to allow for authorisation to be conferred by the original authors. METHODS: In cooperation with the original authors the STARD statement was translated according to the ISPOR steps: (1) Preparation, (2) Forward Translation, (3) Reconciliation, (4) Back Translation, (5) Back Translation Review, (6) Harmonisation, (7) Cognitive Debriefing, which evaluated comprehensiveness and linguistic style with marks from 1 (very good) to 6 (insufficient), and (8) Review of Cognitive Debriefing Results and Finalisation. RESULTS: Die ISPOR criteria applied reasonably to the translation process, which required the work input and energy of four scientists and one professional translator and 177 accumulated working hours. The cognitive debriefing resulted in average grades 1.62±0.33 and 1.72±0.39 for comprehensiveness and linguistic style, respectively. Finally, the German STARD version was authorised by the original authors. CONCLUSION: Die ISPOR guidelines seem to be a suitable means to facilitate the structured adaptation of defined criteria for the reporting of studies, such as the STARD statement, to other languages.

[Preoperative fasting in labour]. / Nahrungskarenz im Kreisssaal--Ein traditioneller Qualitätsstandard auf dem Prüfstand.

Numerous scientific case reports and observational studies, including that of Curtis Mendelson with its great historical relevance, have reported the problem of aspiration pneumonitis during labour. Because of this, strict fasting prior to delivery to reduce pulmonary aspiration has been doctrine since the 1940s. However, maternal mortality from anaesthesia, particularly from aspiration, has dropped dramatically over recent decades. This is due both to far-reaching improved quality of care as well as technical progress in anaesthesia, which increasingly challenge the scientific basis for fasting in obstetric anaesthesia. Strict fasting has never been proven to reduce morbidity or mortality in labouring women. Because of the physiological and anatomical changes of pregnancy, gastric emptying is theoretically prolonged, and therefore the risk of aspiration is assumed to be increased. However, the available data with patients receiving clear fluids run contrary to this assumption, or at least dispute its clinical relevance. Recent studies report positive influence of reduced fasting time on both maternal comfort and maternal/fetal metabolism without increased risk. This has already led to meaningful discussion regarding a corresponding change in official recommendations.

The resistance to changing guidelines--what are the challenges and how to meet them.

Bridging the gap between scientific evidence and its practical application is of the utmost importance in improving the quality of care and increasing patient safety. Guidelines based on evidenced-based medicine (EBM) have led to improved performances and better outcomes. However, even though scientific data are available, resistance to adopting evidence-based guidelines is still enormous. Significant barriers hinder the introduction of best medical practice into the daily clinical routine. The barriers to implementing change are complex, multifunctional, and influenced on many levels by various interests both inside and outside the health-care system. Political, organizational, financial, cultural and scientific interests are regarded as being as important as the perception of patients and health workers. Strategies need to be planned which take account of the multidimensional character of quality of care and incorporate it at the various levels. The conclusion, therefore, is that we need to combine methods and tools to tailor our interventions to the patient's needs.

Preoperative oral carbohydrate administration to ASA III-IV patients undergoing elective cardiac surgery.

In this study we investigated the effects of preoperative oral carbohydrate administration on postoperative insulin resistance (PIR), gastric fluid volume, preoperative discomfort, and variables of organ dysfunction in ASA physical status III-IV patients undergoing elective cardiac surgery, including those with noninsulin-dependent Type-2 diabetes mellitus. Before surgery, 188 patients were randomized to receive a clear 12.5% carbohydrate drink (CHO), flavored water (placebo), or to fast overnight (control). CHO and placebo were treated in double-blind format and received 800 mL of the corresponding beverage in the evening and 400 mL 2 h before surgery. Patients were monitored from induction of general anesthesia until 24 h postoperatively. Exogenous insulin requirements to control blood glucose levels

[The alcoholic patient in the daily routine]. / Der Alkoholkranke als Patient. Relevanz und Umgang mit der Alkoholkrankheit im medizinischen Alltag.

Chronic alcohol abuse is of significant clinical and economic relevance. A major part of internal medical pathology is associated with chronic alcoholism. 50% of all accidents with subsequent traumatic injuries are related to alcohol intake. Patients who are chronic alcohol abusers have prolonged hospital stays and substantial increases in postoperative morbidity. A sophisticated diagnosis of alcoholism within standard clinical routine is often difficult, and in most cases the treatment of alcohol-related diseases and complications is protracted and requires increased energy expenditure by the treating physicians. In surgical patients, chronic alcohol abuse is associated with a 3- to 4-fold risk of infections, sepsis, cardiac and bleeding complications. Therefore, the patients themselves, along with the general practitioner and an in-hospital interdisciplinary team should cooperate in medical and operative treatment in order to attain better clinical outcome. Each patient history should include a detailed assessment of the quantity of daily alcohol intake. Alcoholic diagnostic regimens including questionnaires (i.e. CAGE, AUDIT) in combination with specific laboratory markers (CDT, GGT, MCV), if implemented, could prove valuable, especially in cases where major surgical procedures are considered. Strict abstinence by alcoholic patients with organ pathology in medical and elective surgical settings as well as the prophylactic treatment of pre-operative alcohol withdrawal appear to be useful strategies to reduce the risk of complications. Short-term interventions are associated with reduced alcohol intake and decreased incidence of re-trauma. Considering the clinical relevance of alcohol abuse, sufficient screening, interventions, and open approaches to address alcohol problems should be important components of the daily clinical routine in outpatient clinics, emergency rooms, in GPs' offices and in general hospitals.