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1.
Front Surg ; 11: 1415010, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38826811

RESUMEN

Introduction: In recent years advances have been made in the microsurgical treatment of congenital or acquired central lymphatic lesions. While acquired lesions can result from any surgery or trauma of the central lymphatic system, congenital lymphatic lesions can have a variety of manifestations, ranging from singular thoracic duct abnormalities to complex multifocal malformations. Both conditions may cause recurrent chylous effusions and downstream lymphatic congestion depending on the anatomical location of the thoracic duct lesion and are associated with an increased mortality due to the permanent loss of protein and fluid. Methods: We present a case series of eleven patients undergoing central lymphatic reconstruction, consisting of one patient with a cervical iatrogenic thoracic duct lesion and eleven patients with different congenital thoracic duct lesions or thrombotic occlusions. Results: Anastomosis of the thoracic duct and a nearby vein was performed on different anatomical levels depending on the underlying central lymphatic pathology. Cervical (n = 4), thoracic (n = 1) or abdominal access (n = 5) was used for central lymphatic reconstruction with promising results. In 9 patients a postoperative benefit with varying degrees of symptom regression was reported. Conclusion: The presented case series illustrates the current rapid advances in the field of central microsurgical reconstruction of lymphatic lesions alongside the relevant literature.

2.
J Orthop Traumatol ; 25(1): 30, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850466

RESUMEN

BACKGROUND: Rotator cuff disorders, whether symptomatic or asymptomatic, may result in abnormal shoulder kinematics (scapular rotation and glenohumeral translation). This study aimed to investigate the effect of rotator cuff tears on in vivo shoulder kinematics during a 30° loaded abduction test using single-plane fluoroscopy. MATERIALS AND METHODS: In total, 25 younger controls, 25 older controls and 25 patients with unilateral symptomatic rotator cuff tears participated in this study. Both shoulders of each participant were analysed and grouped on the basis of magnetic resonance imaging into healthy, rotator cuff tendinopathy, asymptomatic and symptomatic rotator cuff tears. All participants performed a bilateral 30° arm abduction and adduction movement in the scapular plane with handheld weights (0, 2 and 4 kg) during fluoroscopy acquisition. The range of upward-downward scapular rotation and superior-inferior glenohumeral translation were measured and analysed during abduction and adduction using a linear mixed model (loads, shoulder types) with random effects (shoulder ID). RESULTS: Scapular rotation was greater in shoulders with rotator cuff tendinopathy and asymptomatic rotator cuff tears than in healthy shoulders. Additional load increased upward during abduction and downward during adduction scapular rotation (P < 0.001 in all groups but rotator cuff tendinopathy). In healthy shoulders, upward scapular rotation during 30° abduction increased from 2.3° with 0-kg load to 4.1° with 4-kg load and on shoulders with symptomatic rotator cuff tears from 3.6° with 0-kg load to 6.5° with 4-kg load. Glenohumeral translation was influenced by the handheld weights only in shoulders with rotator cuff tendinopathy (P ≤ 0.020). Overall, superior glenohumeral translation during 30° abduction was approximately 1.0 mm with all loads. CONCLUSIONS: The results of glenohumeral translation comparable to control but greater scapular rotations during 30° abduction in the scapular plane in rotator cuff tears indicate that the scapula compensates for rotator cuff deficiency by rotating. Further analysis of load-dependent joint stability is needed to better understand glenohumeral and scapula motion. LEVEL OF EVIDENCE: Level 2. TRIAL REGISTRATION: Ethical approval was obtained from the regional ethics committee (Ethics Committee Northwest Switzerland EKNZ 2021-00182), and the study was registered at clinicaltrials.gov on 29 March 2021 (trial registration number NCT04819724, https://clinicaltrials.gov/ct2/show/NCT04819724 ).


Asunto(s)
Lesiones del Manguito de los Rotadores , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fenómenos Biomecánicos , Estudios de Casos y Controles , Fluoroscopía , Imagen por Resonancia Magnética , Rango del Movimiento Articular/fisiología , Rotación , Lesiones del Manguito de los Rotadores/fisiopatología , Lesiones del Manguito de los Rotadores/diagnóstico por imagen , Articulación del Hombro/fisiopatología , Articulación del Hombro/diagnóstico por imagen , Soporte de Peso/fisiología
3.
J Hematol Oncol ; 17(1): 43, 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38853260

RESUMEN

BACKGROUND: Neutrophils play a crucial role in inflammation and in the increased thrombotic risk in myeloproliferative neoplasms (MPNs). We have investigated how neutrophil-specific expression of JAK2-V617F or CALRdel re-programs the functions of neutrophils. METHODS: Ly6G-Cre JAK2-V617F and Ly6G-Cre CALRdel mice were generated. MPN parameters as blood counts, splenomegaly and bone marrow histology were compared to wild-type mice. Megakaryocyte differentiation was investigated using lineage-negative bone marrow cells upon in vitro incubation with TPO/IL-1ß. Cytokine concentrations in serum of mice were determined by Mouse Cytokine Array. IL-1α expression in various hematopoietic cell populations was determined by intracellular FACS analysis. RNA-seq to analyse gene expression of inflammatory cytokines was performed in isolated neutrophils from JAK2-V617F and CALR-mutated mice and patients. Bioenergetics of neutrophils were recorded on a Seahorse extracellular flux analyzer. Cell motility of neutrophils was monitored in vitro (time lapse microscopy), and in vivo (two-photon microscopy) upon creating an inflammatory environment. Cell adhesion to integrins, E-selectin and P-selection was investigated in-vitro. Statistical analysis was carried out using GraphPad Prism. Data are shown as mean ± SEM. Unpaired, two-tailed t-tests were applied. RESULTS: Strikingly, neutrophil-specific expression of JAK2-V617F, but not CALRdel, was sufficient to induce pro-inflammatory cytokines including IL-1 in serum of mice. RNA-seq analysis in neutrophils from JAK2-V617F mice and patients revealed a distinct inflammatory chemokine signature which was not expressed in CALR-mutant neutrophils. In addition, IL-1 response genes were significantly enriched in neutrophils of JAK2-V617F patients as compared to CALR-mutant patients. Thus, JAK2-V617F positive neutrophils, but not CALR-mutant neutrophils, are pathogenic drivers of inflammation in MPN. In line with this, expression of JAK2-V617F or CALRdel elicited a significant difference in the metabolic phenotype of neutrophils, suggesting a stronger inflammatory activity of JAK2-V617F cells. Furthermore, JAK2-V617F, but not CALRdel, induced a VLA4 integrin-mediated adhesive phenotype in neutrophils. This resulted in reduced neutrophil migration in vitro and in an inflamed vessel. This mechanism may contribute to the increased thrombotic risk of JAK2-V617F patients compared to CALR-mutant individuals. CONCLUSIONS: Taken together, our findings highlight genotype-specific differences in MPN-neutrophils that have implications for the differential pathophysiology of JAK2-V617F versus CALR-mutant disease.


Asunto(s)
Inflamación , Janus Quinasa 2 , Trastornos Mieloproliferativos , Neutrófilos , Animales , Neutrófilos/metabolismo , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Ratones , Trastornos Mieloproliferativos/genética , Trastornos Mieloproliferativos/patología , Trastornos Mieloproliferativos/metabolismo , Humanos , Inflamación/genética , Inflamación/patología , Calreticulina/genética , Calreticulina/metabolismo , Ratones Transgénicos , Ratones Endogámicos C57BL , Citocinas/metabolismo
4.
Pneumologie ; 2024 Jun 10.
Artículo en Alemán | MEDLINE | ID: mdl-38857625

RESUMEN

Parasitic infections by Echinococcus granulosus are rare in Germany, and predominantly affect individuals with a migration background. Liver and lungs are the most commonly affected organs. Pulmonary cysts often remain asymptomatic until rupture, at which point symptoms may manifest. The diagnostic approach typically involves a combination of imaging modalities and serological tests, occasionally supplemented by molecular genetic methods. Given the global movements of migration, considerations of the epidemiology of common diseases in the country of origin should also be taken into account in the differential diagnosis. We present the unusual case of a pneumogenic sepsis in a young man from Syria, where the combination of medical history alongside radiological, serological, and molecular genetic investigations ultimately led to the diagnosis of a severe pulmonary echinococcosis with rupture.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38816192

RESUMEN

OBJECTIVE: Retinopathy of prematurity (ROP) is a leading yet avoidable cause of childhood blindness. Screening for ROP is highly effective in preventing blindness secondary to ROP. We provide epidemiological data on ROP screening and treatment in Germany since 2010 and evaluate the effects of recently adopted as well as potential future screening guideline adaptations. METHODS: Data sets of the German Quality Assurance Procedure in Neonatology, the ROP screening programme of two German university hospitals, and the German section of the EU-ROP Registry were analysed. RESULTS: Over the 13-year period from 2010 to 2022, 141 550 infants received ROP screening in Germany. Mean annual incidences of ROP were 3.5% (±0.2%) in premature infants and 19.6% (±2.3%) in screened infants. Of screened infants, 2.0% (±0.3%) received treatment for ROP. Treatment preferences shifted from laser coagulation (46.2% in 2015) to anti-vascular endothelial growth factor therapy (83.7% in 2022). A revision of national screening criteria in 2020 with a reduction of the gestational age limit from <32 to <31 weeks resulted in a decrease of the annual number of infants requiring screening by 25.8% (p<0.001). Infants with a birth weight ≥1500 g accounted for 35.2% of the screening population but only for 0.4% of ROP stage 3-5 cases. CONCLUSIONS: Collection of epidemiological data on ROP in national and international registries enables the continuous surveillance and adaptation of ROP screening and treatment criteria. In Germany, infants with a birth weight ≥1500 g have a very low risk of developing treatment-requiring ROP, supporting an upper birth weight limit for ROP screening.

6.
Heart Rhythm ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38762133

RESUMEN

BACKGROUND: Stroke remains one of the most serious complications in atrial fibrillation (AF) patients and has been linked to disturbances of the autonomic nervous system. OBJECTIVE: We hypothesized that impaired cardiac autonomic function might be associated with an enhanced stroke risk in AF patients. METHODS: We enrolled 1922 AF patients who were either in sinus rhythm (SR-group, n=1121) or AF (AF-group, n=801) on a 5-minute resting ECG recording. HRV triangular index (HRVI), standard deviation of normal-to-normal intervals, root mean square root of successive differences of normal-to-normal intervals, mean heart rate, 5-min total power and power in the high frequency, low frequency and very low frequency range were calculated. We constructed Cox regression models to examine the association of HRV parameters with the composite endpoint of stroke or systemic embolism. RESULTS: Mean age was 71±8 years in the SR group and 75±8 in the AF group. 37 patients in the SR group (3.4%) and 60 patients in the AF group (8.0%) experienced a stroke or systemic embolism during a follow-up time of 5 years. In patients with SR, HRVI <15 was the strongest HRV parameter to be associated with stroke or systemic embolism (hazard ratio 3.04; 95% confidence interval 1.3-7.0; p=0.009) after adjustment for multiple confounders. In the AF group, we found no HRV parameter to be associated with the composite endpoint. CONCLUSION: HRVI measured during SR on a single 5-minute ECG recording is independently associated with stroke or systemic embolism in AF patients. HRV analysis in SR may help to improve risk stratification in AF patients.

7.
ACS Omega ; 9(18): 20350-20358, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38737039

RESUMEN

2,3,3,3-Tetrafluoro-2-(trifluoromethyl) propanenitrile (C4F7N) is being researched as an alternative to sulfur hexafluoride (SF6) for applications in gas-insulated switchgear. We independently assessed the effectiveness of gas chromatography-mass spectrometry (GC-MS) and a novel method of feedback-assisted multipass cavity spontaneous Raman spectroscopy (SRS) for the trace quantification of impurities in C4F7N and its related byproducts. A total of 14 gases were identified with estimated concentrations as low as 20 ppm (ppm) for C3F6 using GC-MS and 7.4 ppm for CH4 using SRS and as high as 500 ppm for CF4 using GC-MS and 1430 ppm for CO using SRS. While GC-MS is highly effective in selectively detecting and quantifying trace contaminants, it necessitates separate detectors for various gases, such as CH4 and H2. SRS succeeded in detecting CF4 and C2F6 at concentrations of 465 and 100 ppm, respectively, and in placing an upper bound of several hundred ppm for the other analytes. Crucially, SRS holds potential for portability-and thus for field applications-in gas-insulated switchgear equipment diagnostics.

8.
Sci Rep ; 14(1): 10440, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714750

RESUMEN

A wide variety of treatments have been developed to improve respiratory function and quality of life in patients with bilateral vocal fold paresis (BVFP). One experimental method is the electrical activation of the posterior cricoarytenoid (PCA) muscle with a laryngeal pacemaker (LP) to open the vocal folds. We used an ovine (sheep) model of unilateral VFP to study the long-term effects of functional electrical stimulation on the PCA muscles. The left recurrent laryngeal nerve was cryo-damaged in all animals and an LP was implanted except for the controls. After a reinnervation phase of six months, animals were pooled into groups that received either no treatment, implantation of an LP only, or implantation of an LP and six months of stimulation with different duty cycles. Automated image analysis of fluorescently stained PCA cross-sections was performed to assess relevant muscle characteristics. We observed a fast-to-slow fibre type shift in response to nerve damage and stimulation, but no complete conversion to a slow-twitch-muscle. Fibre size, proportion of hybrid fibres, and intramuscular collagen content were not substantially altered by the stimulation. These results demonstrate that 30 Hz burst stimulation with duty cycles of 40% and 70% did not induce PCA atrophy or fibrosis. Thus, long-term stimulation with an LP is a promising approach for treating BVFP in humans without compromising muscle conditions.


Asunto(s)
Modelos Animales de Enfermedad , Terapia por Estimulación Eléctrica , Músculos Laríngeos , Parálisis de los Pliegues Vocales , Animales , Ovinos , Parálisis de los Pliegues Vocales/terapia , Parálisis de los Pliegues Vocales/fisiopatología , Terapia por Estimulación Eléctrica/métodos , Músculos Laríngeos/fisiopatología , Humanos , Marcapaso Artificial/efectos adversos , Pliegues Vocales/fisiopatología , Pliegues Vocales/patología , Femenino
9.
Cell Rep ; 43(5): 114153, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38687643

RESUMEN

Gut-draining mesenteric and celiac lymph nodes (mLNs and celLNs) critically contribute to peripheral tolerance toward food and microbial antigens by supporting the de novo induction of regulatory T cells (Tregs). These tolerogenic properties of mLNs and celLNs are stably imprinted within stromal cells (SCs) by microbial signals and vitamin A (VA), respectively. Here, we report that a single, transient gastrointestinal infection in the neonatal, but not adult, period durably abrogates the efficient Treg-inducing capacity of celLNs by altering the subset composition and gene expression profile of celLNSCs. These cells carry information about the early-life pathogen encounter until adulthood and durably instruct migratory dendritic cells entering the celLN with reduced tolerogenic properties. Mechanistically, transiently reduced VA levels cause long-lasting celLN functional impairment, which can be rescued by early-life treatment with VA. Together, our data highlight the therapeutic potential of VA to prevent sequelae post gastrointestinal infections in infants.


Asunto(s)
Ganglios Linfáticos , Linfocitos T Reguladores , Vitamina A , Animales , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/patología , Ganglios Linfáticos/efectos de los fármacos , Vitamina A/farmacología , Vitamina A/uso terapéutico , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/efectos de los fármacos , Ratones , Animales Recién Nacidos , Tolerancia Inmunológica/efectos de los fármacos , Células Dendríticas/inmunología , Ratones Endogámicos C57BL , Femenino
10.
Sci Rep ; 14(1): 7761, 2024 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565603

RESUMEN

Prognostic factors for overall survival (OS), percutaneous endoscopic gastrostomy (PEG) dependency, and long-term speech rehabilitation via voice prosthesis (VP) after laryngectomy for laryngeal or hypopharyngeal cancer were investigated in a retrospective population-based study in Thuringia, Germany. A total of 617 patients (68.7% larynx; hypopharynx; 31.3%; 93.7% men; median age 62 years; 66.0% stage IV) from 2001 to 2020 were included. Kaplan-Meier and Cox multivariable regression analyses were performed. 23.7% of patients received a PEG. 74.7% received a VP. Median OS was 131 months. Independent factors for lower OS were stage IV (compared to stage II; hazard ratio [HR] = 3.455; confidence interval [CI] 1.395-8.556) and laryngectomy for a recurrent disease (HR = 1.550; CI 1.078-2.228). Median time to PEG removal was 7 months. Prior partial surgery before laryngectomy showed a tendency for independent association for later PEG removal (HR = 1.959; CI 0.921-4.167). Postoperative aspiration needing treatment was an independent risk factor (HR = 2.679; CI 1.001-7.167) for later definitive VP removal. Laryngectomy continuously plays an important role in a curative daily routine treatment setting of advanced laryngeal or hypopharyngeal cancer in Germany. Long-term dependency on nutrition via PEG is an important issue, whereas use of VP is a stable long-term measure for voice rehabilitation.


Asunto(s)
Neoplasias Hipofaríngeas , Neoplasias Laríngeas , Laringe , Masculino , Humanos , Persona de Mediana Edad , Femenino , Laringectomía , Estudios Retrospectivos , Neoplasias Hipofaríngeas/cirugía , Neoplasias Laríngeas/cirugía , Laringe/cirugía , Resultado del Tratamiento
11.
Lancet Respir Med ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38643780

RESUMEN

BACKGROUND: Vitamin A plays a key role in lung development, but there is no consensus regarding the optimal vitamin A dose and administration route in extremely low birthweight (ELBW) infants. We aimed to assess whether early postnatal additional high-dose fat-soluble enteral vitamin A supplementation versus placebo would lower the rate of moderate or severe bronchopulmonary dysplasia or death in ELBW infants receiving recommended basic enteral vitamin A supplementation. METHODS: This prospective, multicentre, randomised, parallel-group, double-blind, placebo-controlled, investigator-initiated phase 3 trial conducted at 29 neonatal intensive care units in Austria and Germany assessed early high-dose enteral vitamin A supplementation (5000 international units [IU]/kg per day) or placebo (peanut oil) for 28 days in ELBW infants. Eligible infants had a birthweight of more than 400 g and less than 1000 g; gestational age at birth of 32+0 weeks postmenstrual age or younger; and the need for mechanical ventilation, non-invasive respiratory support, or supplemental oxygen within the first 72 h of postnatal age after admission to the neonatal intensive care unit. Participants were randomly assigned by block randomisation with variable block sizes (two and four). All participants received basic vitamin A supplementation (1000 IU/kg per day). The composite primary endpoint was moderate or severe bronchopulmonary dysplasia or death at 36 weeks postmenstrual age, analysed in the intention-to-treat population. This trial was registered with EudraCT, 2013-001998-24. FINDINGS: Between March 2, 2015, and Feb 27, 2022, 3066 infants were screened for eligibility at the participating centres. 915 infants were included and randomly assigned to the high-dose vitamin A group (n=449) or the control group (n=466). Mean gestational age was 26·5 weeks (SD 2·0) and mean birthweight was 765 g (162). Moderate or severe bronchopulmonary dysplasia or death occurred in 171 (38%) of 449 infants in the high-dose vitamin A group versus 178 (38%) of 466 infants in the control group (adjusted odds ratio 0·99, 95% CI 0·73-1·55). The number of participants with at least one adverse event was similar between groups (256 [57%] of 449 in the high-dose vitamin A group and 281 [60%] of 466 in the control group). Serum retinol concentrations at baseline, at the end of intervention, and at 36 weeks postmenstrual age were similar in the two groups. INTERPRETATION: Early postnatal high-dose fat-soluble enteral vitamin A supplementation in ELBW infants was safe, but did not change the rate of moderate or severe bronchopulmonary dysplasia or death and did not substantially increase serum retinol concentrations. FUNDING: Deutsche Forschungsgemeinschaft and European Clinical Research Infrastructures Network (ECRIN).

12.
Acta Orthop ; 95: 152-156, 2024 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-38597205

RESUMEN

BACKGROUND AND PURPOSE: Large language models like ChatGPT-4 have emerged. They hold the potential to reduce the administrative burden by generating everyday clinical documents, thus allowing the physician to spend more time with the patient. We aimed to assess both the quality and efficiency of discharge documents generated by ChatGPT-4 in comparison with those produced by physicians. PATIENTS AND METHODS: To emulate real-world situations, the health records of 6 fictional orthopedic cases were created. Discharge documents for each case were generated by a junior attending orthopedic surgeon and an advanced orthopedic resident. ChatGPT-4 was then prompted to generate the discharge documents using the same health record information. The quality assessment was performed by an expert panel (n = 15) blinded to the source of the documents. As secondary outcome, the time required to generate the documents was compared, logging the duration of the creation of the discharge documents by the physician and by ChatGPT-4. RESULTS: Overall, both ChatGPT-4 and physician-generated notes were comparable in quality. Notably, ChatGPT-4 generated discharge documents 10 times faster than the traditional method. 4 events of hallucinations were found in the ChatGPT-4-generated content, compared with 6 events in the human/physician produced notes. CONCLUSION: ChatGPT-4 creates orthopedic discharge notes faster than physicians, with comparable quality. This shows it has great potential for making these documents more efficient in orthopedic care. ChatGPT-4 has the potential to significantly reduce the administrative burden on healthcare professionals.


Asunto(s)
Cirujanos Ortopédicos , Ortopedia , Humanos , Proyectos Piloto , Alta del Paciente , Personal de Salud
13.
Cell Rep ; 43(4): 113992, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38536815

RESUMEN

Insulin is packaged into secretory granules that depart the Golgi and undergo a maturation process that involves changes in the protein and lipid composition of the granules. Here, we show that insulin secretory granules form physical contacts with the endoplasmic reticulum and that the lipid exchange protein oxysterol-binding protein (OSBP) is recruited to these sites in a Ca2+-dependent manner. OSBP binding to insulin granules is positively regulated by phosphatidylinositol-4 (PI4)-kinases and negatively regulated by the PI4 phosphate (PI(4)P) phosphatase Sac2. Loss of Sac2 results in excess accumulation of cholesterol on insulin granules that is normalized when OSBP expression is reduced, and both acute inhibition and small interfering RNA (siRNA)-mediated knockdown of OSBP suppress glucose-stimulated insulin secretion without affecting insulin production or intracellular Ca2+ signaling. In conclusion, we show that lipid exchange at endoplasmic reticulum (ER)-granule contact sites is involved in the exocytic process and propose that these contacts act as reaction centers with multimodal functions during insulin granule maturation.


Asunto(s)
Colesterol , Retículo Endoplásmico , Secreción de Insulina , Insulina , Antígenos de Histocompatibilidad Menor , Receptores de Esteroides , Vesículas Secretoras , Retículo Endoplásmico/metabolismo , Vesículas Secretoras/metabolismo , Animales , Colesterol/metabolismo , Insulina/metabolismo , Receptores de Esteroides/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Ratones , Humanos , Calcio/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Glucosa/metabolismo
14.
Chem Sci ; 15(13): 4871-4880, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38550689

RESUMEN

Supported bimetallic nanoparticles (NPs) often display improved catalytic performances (activity and/or selectivity). Yet, structure-activity relationships are difficult to derive due to the multitude of possible compositions, interfaces and alloys. This is notably true for bimetallic NPs used in the selective hydrogenation of CO2 to methanol, where the NPs respond dynamically to the chemical potential of the reactants and products. Herein, we use a combined computational and experimental approach that leverages ab initio Molecular Dynamics (AIMD) and Metadynamics (MTD) in conjunction with in situ X-ray absorption spectroscopy, chemisorption and CO-IR, to explore the dynamic structures and interactions with adsorbates under various CO2 hydrogenation conditions in highly active and selective silica-supported PdGa NPs. We find that PdGa alloying generates isolated Pd sites at the NP surface, changing the dominant binding modes of relevant adsorbates compared to pure Pd NPs: CO molecules mainly occupy atop sites and hydrides switch from mainly internal to atop and bridge sites. Under more oxidizing conditions, akin to CO2 hydrogenation, Ga is partially oxidized, forming a GaOX layer on the NP surface, with a partially dealloyed PdGa core and some remaining isolated Pd surface sites. Overall, these bimetallic NPs show high structural dynamics and a variable extent of alloying depending on the adsorbates relevant to CO2 hydrogenation. This work highlights that AIMD/MTD is a powerful approach to elucidate structural dynamics at a single particle level in complex catalytic systems.

15.
J Biomech ; 166: 112055, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38522362

RESUMEN

Glenohumeral biomechanics after rotator cuff (RC) tears have not been fully elucidated. This study aimed to investigate the muscle compensatory mechanism in weight-bearing shoulders with RC tears and asses the induced pathomechanics (i.e., glenohumeral translation, joint instability, center of force (CoF), joint reaction force). An experimental, glenohumeral simulator with muscle-mimicking cable system was used to simulate 30° scaption motion. Eight fresh-frozen shoulders were prepared and mounted in the simulator. Specimen-specific scapular anthropometry was used to test six RC tear types, with intact RC serving as the control, and three weight-bearing loads, with the non-weight-bearing condition serving as the control. Glenohumeral translation was calculated using instantaneous helical axis. CoF, muscle forces, and joint reaction forces were measured using force sensors integrated into the simulator. Linear mixed effects models (RC tear type and weight-bearing) with random effects (specimen and sex) were used to assess differences in glenohumeral biomechanics. RC tears did not change the glenohumeral translation (p > 0.05) but shifted the CoF superiorly (p ≤ 0.005). Glenohumeral translation and joint reaction forces increased with increasing weight bearing (p < 0.001). RC and deltoid muscle forces increased with the presence of RC tears (p ≤ 0.046) and increased weight bearing (p ≤ 0.042). The synergistic muscles compensated for the torn RC tendons, and the glenohumeral translation remained comparable to that for the intact RC tendons. However, in RC tears, the more superior CoF was close to where glenoid erosion occurs in RC tear patients with secondary osteoarthritis. These findings underscore the importance of early detection and precise management of RC tears.


Asunto(s)
Lesiones del Manguito de los Rotadores , Articulación del Hombro , Humanos , Hombro/fisiología , Manguito de los Rotadores/fisiología , Articulación del Hombro/fisiología , Fenómenos Biomecánicos , Soporte de Peso , Cadáver , Rango del Movimiento Articular/fisiología
16.
NEJM Evid ; 3(1): EVIDoa2300172, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38320514

RESUMEN

BACKGROUND: Systemic glucocorticoids are commonly used for primary therapy of idiopathic sudden sensorineural hearing loss (ISSNHL). However, the comparative effectiveness and risk profiles of high-dose over lower-dose regimens remain unknown. METHODS: We randomly assigned patients with sudden hearing loss of greater than or equal to 50 dB within 7 days from onset to receive either 5 days of high-dose intravenous prednisolone at 250 mg/d (HD-Pred), 5 days of high-dose oral dexamethasone at 40 mg/d (HD-Dex), or, as a control, 5 days of oral prednisolone (Pred-Control) at 60 mg/d followed by 5 days of tapering doses. The primary outcome was the change in hearing threshold (pure tone average) in the three most affected contiguous frequencies from baseline to day 30. Secondary outcomes included speech understanding, tinnitus, communication competence, quality of life, hypertension, and insulin resistance. RESULTS: A total of 325 patients were randomly assigned. Mean change in 3PTAmost affected hearing threshold from baseline to 30 days was 34.2 dB (95% CI, 28.4 to 40.0) in the HD-Pred group, 41.4 dB (95% CI, 35.6 to 47.2) in the HD-Dex group, and 41.0 dB (95% CI, 35.2 to 46.8) in the Pred-Control group (P=0.09 for analysis of variance). There were more adverse events related to trial medication in the HD-Pred (n=73) and HD-Dex (n=76) groups than in the Pred-Control group (n=46). CONCLUSIONS: Systemic high-dose glucocorticoid therapy was not superior to a lower-dose regimen in patients with ISSNHL, and it was associated with a higher risk of side effects. (Funded by the Federal Ministry of Education and Research [BMBF]; EudraCT number, 2015­002602­36.)


Asunto(s)
Glucocorticoides , Pérdida Auditiva Súbita , Adulto , Humanos , Dexametasona , Pérdida Auditiva Súbita/inducido químicamente , Prednisona , Resultado del Tratamiento
17.
Infection ; 52(3): 1099-1111, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38366304

RESUMEN

PURPOSE: In late 2022, a surge of severe S. pyogenes infections was reported in several European countries. This study assessed hospitalizations and disease severity of community-acquired bacterial infections with S. pyogenes, S. pneumoniae, N. meningitidis, and H. influenzae among children in North Rhine-Westphalia (NRW), Germany, during the last quarter of 2022 compared to long-term incidences. METHODS: Hospital cases due to bacterial infections between October and December 2022 were collected in a multicenter study (MC) from 59/62 (95%) children's hospitals in NRW and combined with surveillance data (2016-2023) from the national reference laboratories for streptococci, N. meningitidis, and H. influenzae. Overall and pathogen-specific incidence rates (IR) from January 2016 to March 2023 were estimated via capture-recapture analyses. Expected annual deaths from the studied pathogens were calculated from national death cause statistics. RESULTS: In the MC study, 153 cases with high overall disease severity were reported with pneumonia being most common (59%, n = 91). IRs of bacterial infections declined at the beginning of the COVID-19 pandemic and massively surged to unprecedented levels in late 2022 and early 2023 (overall hospitalizations 3.5-fold), with S. pyogenes and S. pneumoniae as main drivers (18-fold and threefold). Observed deaths during the study period exceeded the expected number for the entire year in NRW by far (7 vs. 0.9). DISCUSSION: The unprecedented peak of bacterial infections and deaths in late 2022 and early 2023 was caused mainly by S. pyogenes and S. pneumoniae. Improved precautionary measures are needed to attenuate future outbreaks.


Asunto(s)
Infecciones Comunitarias Adquiridas , Brotes de Enfermedades , Humanos , Alemania/epidemiología , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Niño , Preescolar , Lactante , Brotes de Enfermedades/estadística & datos numéricos , Adolescente , Femenino , Masculino , Hospitalización/estadística & datos numéricos , Infecciones Bacterianas/epidemiología , Incidencia , Recién Nacido , Streptococcus pyogenes
18.
J Biomech ; 164: 111976, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38342054

RESUMEN

Gait models and reference motions are essential for the objective assessment of walking patterns and therapy progress, as well as research in the field of wearable robotics and rehabilitation devices in general. A human can achieve a desired gait speed by adjusting stride length and/or stride frequency. It is hypothesized that sex, age, and physique of a person have a significant influence on the combination of these parameters. A mathematical description of the relation between gait speed and its determinants is presented in the form of a parameterized analytic function. Based on the statistical significance of the parameters, three models are derived. The first two models are valid for slow to fast walking, which is defined as the interval of approximately 0.6-2.0ms-1, assuming a linear relation of gait speed and stride length, and a non-linear relation of gait speed and stride duration, respectively. The third model is valid for a defined range of walking speed centered at a certain (preferred or spontaneous) gait speed. The latter assumes a constant walk ratio, i.e. the ratio between step or stride length and step or stride frequency, and is recommended for walking at a speed of 1.0-1.6ms-1. On the basis of a large pool of gait datasets, regression coefficients with significance for age and/or body mass index are identified. The presented models allow to estimate the gait cycle duration based on gait speed, sex, age and body mass index of healthy persons walking on even ground.


Asunto(s)
Robótica , Velocidad al Caminar , Humanos , Fenómenos Biomecánicos , Marcha , Caminata
19.
Data Brief ; 53: 110162, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38384309

RESUMEN

The presented data is based on investigations carried out in the framework of the European RFCS (Research Fund for Coal and Steel) funded project HOLLOSSTAB (2016-2019). The campaign's overall goal is presented in more detail in [1] and [2]. The experiments were performed in the Structural Laboratory at the Bundeswehr University Munich to investigate the cross-section behavior of cold-formed square and rectangular hollow sections (SHS and RHS). Two grades of mild and high-strength steel (S355 and S500) and seven section sizes were examined. The profiles cover all four cross-section classes according to EN1993-1-1 [3]. Monotonic stub column, short beam, and long-beam column tests were performed to investigate the load-bearing capacity. The outputs were load-deformation curves for each specimen. The experimental tests were accomplished by digital image correlation (DIC) to obtain an overview of the full deformation field in the specimens. Recalculations with advanced FE-shell simulations, based on scanned specimen geometries (spatial 3D point clouds) and nonlinear material models obtained from tensile coupon tests, were modeled to reproduce the real behavior obtained during the tests.

20.
Ophthalmic Epidemiol ; : 1-8, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38329811

RESUMEN

PURPOSE: The prevalence of trachomatous inflammation-follicular (TF) in Papua New Guinea (PNG) suggests antibiotic mass drug administration (MDA) is needed to eliminate trachoma as a public health problem but the burden of trichiasis is low. As a result, WHO issued bespoke recommendations for the region. If ≥ 20% of 10-14-year-olds have both any conjunctival scarring (C1 or C2 or C3) and corneal pannus and/or Herbert's pits, MDA should be continued. Equally, if ≥ 5% of that group have both moderate/severe conjunctival scarring (C2 or C3) and corneal pannus and/or Herbert's pits, MDA should be continued. METHODS: We identified 14 villages where > 20% of 1-9-year-olds had TF during baseline mapping undertaken 4 years and 1 month previously. Every child aged 10-14 years in those villages was eligible to be examined for clinical signs of corneal pannus, Herbert's pits and conjunctival scarring. A grading system that built on existing WHO grading systems was used. RESULTS: Of 1,293 resident children, 1,181 (91%) were examined. Of 1,178 with complete examination data, only one (0.08%) individual had concurrent scarring and limbal signs. CONCLUSIONS: The WHO-predefined criteria for continuation of MDA were not met. Ongoing behavioural and environmental improvement aspects of the SAFE strategy may contribute to integrated NTD control. Surveillance methods should be strengthened to enable PNG health authorities to identify future changes in disease prevalence.

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