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Abstract In contrast to acute diarrhoea, the aetiology of persistent digestive disorders (≥ 14 days) is poorly understood in low-resource settings and conventional diagnostic approaches lack accuracy. In this multi-country study, we compared multiplex real-time PCR for enteric bacterial, parasitic and viral pathogens in stool samples from symptomatic patients and matched asymptomatic controls in Côte d’Ivoire, Mali and Nepal. Among 1826 stool samples, the prevalence of most pathogens was highest in Mali, being up to threefold higher than in Côte d’Ivoire and up to tenfold higher than in Nepal. In all settings, the most prevalent bacteria were EAEC (13.0–39.9%) and Campylobacter spp. (3.9–35.3%). Giardia intestinalis was the predominant intestinal protozoon (2.9–20.5%), and adenovirus 40/41 was the most frequently observed viral pathogen (6.3–25.1%). Significantly different prevalences between symptomatic and asymptomatic individuals were observed for Campylobacter, EIEC and ETEC in the two African sites, and for norovirus in Nepal. Multiple species pathogen infection was common in Côte d’Ivoire and Mali, but rarely found in Nepal. We observed that molecular testing detected multiple enteric pathogens and showed low discriminatory accuracy to distinguish between symptomatic and asymptomatic individuals. Yet, multiplex PCR allowed for direct comparison between different countries and revealed considerable setting-specificity.

Abstract Concerns are repeatedly raised about possible adverse respiratory effects of wearing filtering face pieces (FFP) during physical activity. This study compared the impact of FFP type 2 (NF95) on pulmonary function, blood gas values, metabolism and discomfort during light, moderate and vigorous physical activity. Healthy adults (n = 13; 6 females, 7 males; mean 31.3, SD 5.5 years) participated in this randomized two-armed (Ergometer cycling with a FFP type 2 vs. no mask) crossover trial. Baseline cardiopulmonary exercise testing and two interventions (masked and unmasked ergometer cycling 40%, 50% and 70% VO2max, 10 min each) were separated by 48 h washout periods. Spiroergometric data (End tidal carbon dioxide partial pressure PetCO2; breathing frequency; inspiration time), blood gas analysis outcomes (capillary carbon dioxide partial pressure, pCO2) and subjective response (Breathing effort and perceived exertion) were contrasted between conditions using ANOVAs. All participants completed the crossover trial, seven started with the FFP2 condition (No adverse events or side effects). FFP2 decreased breathing frequency, prolonged inspiration time, increased perceived breathing effort and PetCO2 (p 0.05) by mask wearing. Conclusion: Mask-induced breathing resistance decreased respiratory performance and limited pulmonary gas exchange. While FFP2 affected subjective breathing effort per se, invasive diagnostics showed that statistically significant metabolic effects are induced from moderate intensity upwards. Trial registration: DRKS-ID: DRKS00030181, Date of registration: 05/09/2022 (German Register for Clinical Trials).

Abstract A recent in-vivo experiment has shown that force can be transmitted between the gastrocnemius and the hamstring muscles due to a direct tissue continuity. However, it remains unclear if this mechanical interaction is affected by the stiffness of the structural connection. This study therefore aimed to investigate the impact of the knee angle on myofascial force transmission across the dorsal knee. A randomized, cross-over study was performed, including n = 56 healthy participants (25.36 ± 3.9 years, 25 females). On two separate days, they adopted a prone position on an isokinetic dynamometer (knee extended or 60° flexed). In each condition, the device moved the ankle three times from maximal plantarflexion to maximal dorsal extension. Muscle inactivity was ensured using EMG. High-resolution ultrasound videos of the semimembranosus (SM) and the gastrocnemius medialis (GM) soft tissue were recorded. Maximal horizontal tissue displacement, obtained using cross-correlation, was examined as a surrogate of force transmission. SM tissue displacement was higher at extended (4.83 ± 2.04 mm) than at flexed knees (3.81 ± 2.36 mm). Linear regression demonstrated significant associations between (1) SM and GM soft tissue displacement (extended: R2 = 0.18, p = 0.001; flexed: R2 = 0.17, p = 0.002) as well as (2) SM soft tissue displacement and ankle range of motion (extended: R2 = 0.103, p = 0.017; flexed: R2 = 0.095, p = 0.022). Our results further strengthen the evidence that local stretching induces a force transmission to neighboring muscles. Resulting remote exercise effects such as increased range of motion, seem to depend on the stiffness of the continuity. Trial registration: DRKS (Deutsches Register Klinischer Studien), registration number DRKS00024420, first registered 08/02/2021, https://drks.de/search/de/trial/DRKS00024420 .

Abstract Numerous functional factors may interactively contribute to the course of self-report functional abilities after anterior cruciate ligament (ACL)-reconstruction. This study purposes to identify these predictors using exploratory moderation-mediation models in a cohort study design. Adults with post unilateral ACL reconstruction (hamstring graft) status and who were aiming to return to their pre-injury type and level of sport were included. Our dependent variables were self-reported function, as assessed by the the KOOS subscales sport (SPORT), and activities of daily living (ADL). The independent variables assessed were the KOOS subscale pain and the time since reconstruction [days]. All other variables (sociodemographic, injury-, surgery-, rehabilitation-specific, kinesiophobia (Tampa Scale of Kinesiophobia), and the presence or absence of COVID-19-associated restrictions) were further considered as moderators, mediators, or co-variates. Data from 203 participants (mean 26 years, SD 5 years) were finally modelled. Total variance explanation was 59% (KOOS-SPORT) and 47% (KOOS-ADL). In the initial rehabilitation phase (

Nodular lymphocyte-predominant Hodgkin lymphoma with IgD+ lymphocyte-predominant (LP) cells is a rare clinical distinct lymphoma subset of B-cell origin. Here the authors show that antigens expressed by Moraxella catarrhalis are recognized by B cell receptors of IgD+ LP cells, suggesting the contribution of chronic antigen stimulation to lymphomagenesis.

BackgroundConnective tissue links the skeletal muscles, creating a body-wide network of continuity. A recent in-vivo experiment demonstrated that passive elongation of the calf caused a caudal displacement of the semimembranosus muscle, indicating force transmission across the dorsal knee joint. However, it remains unclear as to whether this observation is dependent on the joint angle. If force would not be transmitted at flexed knees, this would reduce the number of postures and movements where force transmission is of relevance. Our trial, therefore, aims to investigate the influence of passive calf stretching with the knee in extended and flexed position on dorsal thigh soft tissue displacement.MethodsParticipants are positioned prone on an isokinetic dynamometer. The device performs three repetitions of moving the ankle passively (5°/s) between plantar flexion and maximum dorsiflexion. With a washout-period of 24 hours, this procedure is performed twice in randomised order, once with the knee extended (0°) and once with the knee flexed (60°). Two high-resolution ultrasound devices will be used to visualize the soft tissue of the calf and dorsal thigh during the manoeuvre. Maximal horizontal displacement of the soft tissue [mm] during ankle movement will be quantified as a surrogate of force transmission, using a frame-by-frame cross-correlation analysis of the obtained US videos.DiscussionUnderstanding myofascial force transmission under in-vivo conditions is a pre-requisite for the development of exercise interventions specifically targeting the fascial connective tissue. Our study may thus provide health and fitness professional with the anatomical and functional basis for program design.Trial registrationThe study is registered at the German Clinical Trials Register (TRN: DRKS00024420), registered 8 Februar 2021, https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00024420.

Vibroarthrography measures joint sounds caused by sliding of the joint surfaces over each other. and can be affected by joint health, load and type of movement. Since both warm-up and muscle fatigue lead to local changes in the knee joint (e.g., temperature increase, lubrication of the joint, muscle activation), these may impact knee joint sounds. Therefore, this study investigates the effects of warm-up and muscle fatiguing exercise on knee joint sounds during an activity of daily living. Seventeen healthy, physically active volunteers (25.7 ± 2 years, 7 males) performed a control and an intervention session with a wash-out phase of one week. The control session consisted of sitting on a chair, while the intervention session contained a warm-up (walking on a treadmill) followed by a fatiguing exercise (modified sit-to-stand) protocol. Knee sounds were recorded by vibroarthrography (at the medial tibia plateau and at the patella) at three time points in each session during a sit-to-stand movement. The primary outcome was the mean signal amplitude (MSA, dB). Differences between sessions were determined by repeated measures ANOVA with intra-individual pre-post differences for the warm-up and for the muscle fatigue effect. We found a significant difference for MSA at the medial tibia plateau (intervention: mean 1.51 dB, standard deviation 2.51 dB; control: mean -1.28 dB, SD 2.61 dB; F = 9.5; p = .007; η2 = .37) during extension (from sit to stand) after the warm-up. There was no significant difference for any parameter after the muscle fatiguing exercise (p > .05). The increase in MSA may mostly be explained by an increase in internal knee load and joint friction. However, neuromuscular changes may also have played a role. It appears that the muscle fatiguing exercise has no impact on knee joint sounds in young, active, symptom-free participants during sit to stand.

Lipoproteins are essential components of bacterial membranes. Here the authors present the crystal structures ofPseudomonas aeruginosa and Escherichia coliapolipoprotein N-acyltransferase, which catalyses the final step in the lipoprotein synthesis pathway, and give insights into its mechanism.

Abstract Clonal clusters and gene repertoires of Staphylococcus aureus are essential to understand disease and are well characterized in industrialized countries but poorly analysed in developing regions. The objective of this study was to compare the molecular-epidemiologic profiles of S. aureus isolates from Sub-Saharan Africa and Germany. S. aureus isolates from 600 staphylococcal carriers and 600 patients with community-associated staphylococcal disease were characterized by DNA hybridization, clonal complex (CC) attribution, and principal component (PCA)-based gene repertoire analysis. 73% of all CCs identified representing 77% of the isolates contained in these CCs were predominant in either African or German region. Significant differences between African versus German isolates were found for alleles encoding the accessory gene regulator type, enterotoxins, the Panton-Valentine leukocidin, immune evasion gene cluster, and adhesins. PCA in conjunction with silhouette analysis distinguished nine separable PCA clusters, with five clusters primarily comprising of African and two clusters of German isolates. Significant differences between S. aureus lineages in Africa and Germany may be a clue to explain the apparent difference in disease between tropical/(so-called) developing and temperate/industrialized regions. In low-resource countries further clinical-epidemiologic research is warranted not only for neglected tropical diseases but also for major bacterial infections.

Study designSystematic review.Background and objectivesPreoperative neuromuscular function is predictive for knee function and return to sports (RTS) after reconstruction of the anterior cruciate ligament (ACL). The aim of this review was to examine the potential benefits of prehabilitation on pre-/postoperative objective, self-reported and RTS-specific outcomes.MethodsA systematic search was conducted within three databases. From the 1.071 studies screened, two randomized control trials (RCTs), two control trials (CTs) and two cohort studies (CS) met the inclusion criteria. Methodological quality rating adopted the PEDro- (RCT, CT) or Newcastle-Ottawa-Scale (CS).Results and conclusionsMethodological quality of the included studies was moderate (PEDro score: 6.5 ± 1.7; range 4 to 9). Two studies reported higher increases of the maximal quadriceps torque from baseline to pre-reconstruction: one study in the limb symmetry index (LSI), and one in both legs of the prehabilitation group compared to the controls. At 12-weeks post-reconstruction, one study (from two) indicated that the prehabilitation group had a lesser post-operative decline in the single-leg-hop for distance LSI (clinically meaningful). Similar findings were found in terms of quadriceps strength LSI (one study). At both pre-reconstruction (three studies) and two-year post-surgery (two studies), the prehabilitation groups reached significantly higher self-reported knee function (clinically meaningful) than the controls. RTS tended to be faster (one study). At two years post-surgery, RTS rates (one study) were higher in the prehabilitation groups. The results provide evidence for the relevance of prehabilitation prior to ACL-reconstruction to improve neuromuscular and self-reported knee function as well as RTS. More high quality confirmatory RCTs are warranted.Registration numberPROSPERO 2017: CRD42017065491.

During dynamic ultrasound assessments, unintended transducer movement over the skin needs to be prevented as it may bias the results. The present study investigated the validity of two methods quantifying transducer motion. An ultrasound transducer was moved on a pre-specified 3 cm distance over the semitendinosus muscle of eleven adults (35.8 ± 9.8 years), stopping briefly at intervals of 0.5 cm. Transducer motion was quantified (1) measuring the 2-D displacement of the shadow produced by reflective tape (RT) attached to the skin and (2) using a marker-based, three-dimensional movement analysis system (MAS). Differences between methods were detected with Wilcoxon tests; associations were checked by means of intraclass correlation coefficients (ICC 3.1) and Bland–Altman plots. Values for RT (r = 0.57, p < 0.001) and MAS (r = 0.19, p = 0.002) were significantly higher than true distances (TD). Strong correlations were found between RT and TD (ICC: 0.98, p < 0.001), MAS and TD (ICC: 0.95, p < 0.001), and MAS and RT (ICC: 0.97, p < 0.001). Bland–Altman plots showed narrow limits of agreement for both RT (−0.49 to 0.13 cm) and MAS (−0.49 to 0.34 cm) versus TD. RT and MAS are valid methods to quantify US transducer movement. In view of its low costs and complexity, RT can particularly be recommended for application in research and clinical practice.

A large body of evidence suggests that the 11+ warm-up programme is effective in preventing football-related musculoskeletal injuries. However, despite considerable efforts to promote and disseminate the programme, it is unclear as to whether team head coaches are familiar with the 11+ and how they rate its feasibility. The present study aimed to gather information on awareness and usage among German amateur level football coaches. A questionnaire was administered to 7893 individuals who were in charge of youth and adult non-professional teams. Descriptive and inferential statistics were used to analyse the obtained data. A total of 1223 coaches (16%) returned the questionnaire. There was no risk of a non-response bias (p>.05). At the time of the survey, nearly half of the participants (42.6%) knew the 11+. Among the coaches who were familiar with the programme, three of four reported applying it regularly (at least once per week). Holding a license (φ = .28, p < .0001), high competitive level (Cramer-V = .13, p = .007), and coaching a youth team (φ = .1, p = .001) were associated with usage of 11+. Feasibility and suitability of the 11+ were rated similarly by aware and unaware coaches. Although a substantial share of German amateur level coaches is familiar with the 11+, more than half of the surveyed participants did not know the programme. As the non-usage does not appear to stem from a lack of rated feasibility and suitability, existing communication strategies might need to be revised.

Delayed-onset muscle soreness (DOMS) refers to dull pain and discomfort in people after participating in exercise, sport or recreational physical activities. The aim of this study was to detect underlying mechanical thresholds in an experimental model of DOMS.Randomised study to detect mechanical pain thresholds in a randomised order following experimentally induced DOMS of the non-dominant arm in healthy participants. Main outcome was the detection of the pressure pain threshold (PPT), secondary thresholds included mechanical detection (MDT) and pain thresholds (MPT), pain intensity, pain perceptions and the maximum isometric voluntary force (MIVF).Twenty volunteers (9 female and 11 male, age 25.2 ± 3.2 years, weight 70.5 ± 10.8 kg, height 177.4 ± 9.4 cm) participated in the study. DOMS reduced the PPT (at baseline 5.9 ± 0.4 kg/cm2) by a maximum of 1.5 ± 1.4 kg/cm2 (-24%) at 48 hours (p < 0.001). This correlated with the decrease in MIVF (r = -0.48, p = 0.033). Whereas subjective pain was an indicator of the early 48 hours, the PPT was still present after 72 hours (r = 0.48, p = 0.036). Other mechanical thresholds altered significantly due to DOMS, but did show no clinically or physiologically remarkable changes.Functional impairment following DOMS seems related to the increased excitability of high-threshold mechanosensitive nociceptors. The PPT was the most valid mechanical threshold to quantify the extent of dysfunction. Thus PPT rather than pain intensity should be considered a possible marker indicating the athletes' potential risk of injury.

BACKGROUND:Multiresistant organisms pose a threat for patients and care recipients. Control interventions need to be tailored to region, the type of institution considered, and risk factors. The German state of Saarland is ideally suited to study colonisation epidemiology throughout its various health and care institutions. After conclusion of a large admission prevalence study in acute care hospitals, we now performed a methicillin-resistant Staphylococcus aureus (MRSA) point prevalence study in Saarland long term care facilities (LTCF), allowing for a direct comparison with respect of MRSA prevalence and associated risk factors between these two institutional types located within a confined region. METHODOLOGY AND PRINCIPAL FINDINGS:Of all LTCF of the region, 65/136 participated in the study performed between 09/2013 and 07/2014. Overall, complete microbiological specimen and questionnaires of 2,858 of 4,275 (66.8%) LTCF residents were obtained. 136/2,858 (4.8%) screened residents revealed MRSA carrier status. Multivariate risk factor analysis yielded ulcer/deep soft tissue infection, urinary tract catheter, and MRSA history with multiple MRSA decolonisation cycles to be independently associated with MRSA carrier status. CONCLUSION:As already known from previous studies, colonisation with MRSA is common in LTCF residents even in an area with relatively low MRSA prevalence. This found prevalence can now be related to the acute care admission prevalence (2.2%) as well as to the admission prevalence in acute care geriatric departments (7.6%). The common clonal attribution (spa type) of MRSA isolates prevalent in the LTCF population as well as in the acute care admission population points towards a close relationship between both types of institutions. However, the ostensible absence of risk factors such as "previous hospitalisation" in conjunction with newly identified factors such as "multiple decolonisation cycles" refers to MRSA colonisation risks independent of contact with acute care facilities. Overall, this large LTCF point prevalence study allows data-based, region-tailored decisions on MRSA screening policies and provides a basis for additional preventative measures.

We applied whole-genome sequencing to reconstruct the spatial and temporal dynamics underpinning the expansion of Clostridium difficile ribotype 027 in Germany. Based on re-sequencing of genomes from 57 clinical C. difficile isolates, which had been collected from hospitalized patients at 36 locations throughout Germany between 1990 and 2012, we demonstrate that C. difficile genomes have accumulated sequence variation sufficiently fast to document the pathogen's spread at a regional scale. We detected both previously described lineages of fluoroquinolone-resistant C. difficile ribotype 027, FQR1 and FQR2. Using Bayesian phylogeographic analyses, we show that fluoroquinolone-resistant C. difficile 027 was imported into Germany at least four times, that it had been widely disseminated across multiple federal states even before the first outbreak was noted in 2007, and that it has continued to spread since.

UnlabelledChronic obstructive pulmonary disease (COPD) is a progressive, inflammatory lung disease that affects a large number of patients and has significant impact. One hallmark of the disease is the presence of bacteria in the lower airways.ObjectiveThe aim of this study was to analyze the detailed structure of microbial communities found in the lungs of healthy individuals and patients with COPD. Nine COPD patients as compared and 9 healthy individuals underwent flexible bronchoscopy and BAL was performed. Bacterial nucleic acids were subjected to terminal restriction fragment (TRF) length polymorphism and clone library analysis. Overall, we identified 326 T-RFLP band, 159 in patients and 167 in healthy controls. The results of the TRF analysis correlated partly with the data obtained from clone sequencing. Although the results of the sequencing showed high diversity, the genera Prevotella, Sphingomonas, Pseudomonas, Acinetobacter, Fusobacterium, Megasphaera, Veillonella, Staphylococcus, and Streptococcus constituted the major part of the core microbiome found in both groups. A TRF band possibly representing Pseudomonas sp. monoinfection was associated with a reduction of the microbial diversity. Non-cultural methods reveal the complexity of the pulmonary microbiome in healthy individuals and in patients with COPD. Alterations of the microbiome in pulmonary diseases are correlated with disease.

BACKGROUND: The screening of hospital admission patients for methicillin resistant Staphylococcus aureus (MRSA) is of undisputed value in controlling and reducing the overall MRSA burden; yet, a concerted parallel universal screening intervention throughout all hospitals of an entire German Federal State has not yet been performed. METHODOLOGY/PRINCIPAL FINDINGS: During a four-week period, all 24 acute care hospitals of the State of Saarland participated in admission prevalence screening. Overall, 436/20,027 screened patients revealed MRSA carrier status (prevalence, 2.2/100 patients) with geriatrics and intensive care departments associated with highest prevalence (7.6/100 and 6.3/100, respectively). Risk factor analysis among 17,975 admission patients yielded MRSA history (OR, 4.3; CI₉₅ 2.7-6.8), a skin condition (OR, 3.2; CI₉₅ 2.1-5.0), and/or an indwelling catheter (OR, 2.2; CI₉₅ 1.4-3.5) among the leading risks. Hierarchical risk factor ascertainment of the six risk factors associated with highest odd's ratios would require 31% of patients to be laboratory screened to allow for detection of 67% of all MRSA positive admission patients in the State. CONCLUSIONS/SIGNIFICANCE: State-wide admission prevalence screening in conjunction with risk factor ascertainment yields important information on the distribution of the MRSA burden for hospitals, and allows for data-based decisions on local or institutional MRSA screening policies considering risk factor prevalence and expected MRSA identification rates.

As genotyping of S. aureus is important for epidemiologic research and for hygiene management, methods are required for standardized fast and easily applicable evaluation of closely related epidemic strains with high prevalence in hospitals. In this single centre matched control study we compared a new commercially available DNA microarray (IdentiBAC) with standard spa-typing for S. aureus genotyping. Included in the study was a subgroup of 46 MRSA and matched 46 MSSA nasal isolates of the Saarland University Medical Center collected during a state-wide admission prevalence screening. Microarray (MA) and also spa-typing could easily differentiate the genetically diverse MSSA group. However, due to the predominance of CC5/t003 in the MRSA group a sufficient subtyping required analysis of more complex genetic profiles as was shown here by the MA comprising a total number of 334 different hybridization probes. The genetic repertoire of the MRSA group was characterized by more virulence genes as compared to the MSSA group. The standard evaluation of MA results by the original software into CCs, agr-, SCCmec- and capsule-types was substituted in the present study by implementation of multivariate subtyping of closely related CC5 isolates using three different bioinformatic methods (splits graph, cluster dendrogram, and principal component analysis). Each method used was applicable for standardized and highly discriminative subtyping with high concordance. We propose that the identified S. aureus subtypes with characteristic virulence gene profiles are presumably associated also with virulence and pathogenicity in vivo; however, this remains to be analyzed in future studies. MA was superior to spa-typing for epidemiologic and presumably also provide functional respectively virulence associated characterization of S. aureus isolates. This is of specific importance for the hospital setting. In future, MA could become a new standard test for S. aureus typing in combination with multivariate bioinformatic analysis.

The removal of biofilms from microstructured titanium used for dental implants is a still unresolved challenge. This experimental study investigated disinfection and removal of in situ formed biofilms from microstructured titanium using cold atmospheric plasma in combination with air/water spray. Titanium discs (roughness (Ra): 1.96 µm) were exposed to human oral cavities for 24 and 72 hours (n = 149 each) to produce biofilms. Biofilm thickness was determined using confocal laser scanning microscopy (n = 5 each). Plasma treatment of biofilms was carried out ex vivo using a microwave-driven pulsed plasma source working at temperatures from 39 to 43°C. Following plasma treatment, one group was air/water spray treated before re-treatment by second plasma pulses. Vital microorganisms on the titanium surfaces were identified by contact culture (Rodac agar plates). Biofilm presence and bacterial viability were quantified by fluorescence microscopy. Morphology of titanium surfaces and attached biofilms was visualized by scanning electron microscopy (SEM). Total protein amounts of biofilms were colorimetrically quantified. Untreated and air/water treated biofilms served as controls. Cold plasma treatment of native biofilms with a mean thickness of 19 µm (24 h) to 91 µm (72 h) covering the microstructure of the titanium surface caused inactivation of biofilm bacteria and significant reduction of protein amounts. Total removal of biofilms, however, required additional application of air/water spray, and a second series of plasma treatment. Importantly, the microstructure of the titanium discs was not altered by plasma treatment. The combination of atmospheric plasma and non-abrasive air/water spray is applicable for complete elimination of oral biofilms from microstructured titanium used for dental implants and may enable new routes for the therapy of periimplant disease.