Temporal evolution of ascending aortic aneurysm wall stress predicts all-cause mortality.

OBJECTIVES: Diameter-based risk stratification for elective repair of ascending aortic aneurysm fails to prevent type A dissection in many patients. Aneurysm wall stresses may contribute to risk prediction; however, rates of wall stress change over time are poorly understood. Our objective was to examine aneurysm wall stress changes over 3-5 years and subsequent all-cause mortality. METHODS: Male veterans with <5.5 cm ascending aortic aneurysms and computed tomography at baseline and 3- to 5-year follow-up underwent three-dimensional aneurysm model construction. Peak circumferential and longitudinal wall stresses at systole were calculated using finite element analysis. Temporal trends were assessed by mixed-effects modelling. Changes in aortic wall stresses, diameter and length over time were evaluated as predictors of subsequent 3-year all-cause mortality by Cox proportional hazards modelling. RESULTS: Sixty-two male veterans were included in the study. Yearly changes in geometric and biomechanical measures were 0.12 mm/year (95% confidence interval, 0.04-0.20) for aortic diameter, 0.41 mm/year (0.12-0.71) for aortic length, 1.19 kPa/year -5.94 to 8.33) for peak circumferential stress, and 0.48 kPa/year (-3.89 to 4.84) for peak longitudinal stress. Yearly change in peak circumferential stress was significantly associated with hazard of death-hazard ratio for peak circumferential stress growth per 10 kPa/year, 1.27 (95% CI, 1.02-1.60; P = 0.037); hazard ratio for peak circumferential stress growth ≥ 32 kPa/year, 8.47 (95% CI, 2.42-30; P < 0.001). CONCLUSIONS: In this population of nonsurgical aneurysm patients, large temporal changes in peak circumferential stress, but not aortic diameter or length, was associated with all-cause mortality. Biomechanical stress and stress changes over time may be beneficial as additional risk factors for elective surgery in small aneurysms.

Evaluating ChatGPT Responses on Atrial Fibrillation for Patient Education.

Background ChatGPT is a language model that has gained widespread popularity for its fine-tuned conversational abilities. However, a known drawback to the artificial intelligence (AI) chatbot is its tendency to confidently present users with inaccurate information. We evaluated the quality of ChatGPT responses to questions pertaining to atrial fibrillation for patient education. Our analysis included the accuracy and estimated grade level of answers and whether references were provided for the answers. Methodology ChatGPT was prompted four times and 16 frequently asked questions on atrial fibrillation from the American Heart Association were asked. Prompts included Form 1 (no prompt), Form 2 (patient-friendly prompt), Form 3 (physician-level prompt), and Form 4 (prompting for statistics/references). Responses were scored as incorrect, partially correct, or correct with references (perfect). Flesch-Kincaid grade-level unique words and response lengths were recorded for answers. Proportions of the responses at differing scores were compared using the chi-square analysis. The relationship between form and grade level was assessed using the analysis of variance. Results Across all forms, scoring frequencies were one (1.6%) incorrect, five (7.8%) partially correct, 55 (85.9%) correct, and three (4.7%) perfect. Proportions of responses that were at least correct did not differ by form (p = 0.350), but perfect responses did (p = 0.001). Form 2 answers had a lower mean grade level (12.80 ± 3.38) than Forms 1 (14.23 ± 2.34), 3 (16.73 ± 2.65), and 4 (14.85 ± 2.76) (p < 0.05). Across all forms, references were provided in only three (4.7%) answers. Notably, when additionally prompted for sources or references, ChatGPT still only provided sources on three responses out of 16 (18.8%). Conclusions ChatGPT holds significant potential for enhancing patient education through accurate, adaptive responses. Its ability to alter response complexity based on user input, combined with high accuracy rates, supports its use as an informational resource in healthcare settings. Future advancements and continuous monitoring of AI capabilities will be crucial in maximizing the benefits while mitigating the risks associated with AI-driven patient education.

Pulmonary Embolism in Patients Admitted With Peripartum Cardiomyopathy: Prevalence, Predictors, and Associated In-Hospital Adverse Events.

Introduction Peripartum cardiomyopathy (PPCM) is defined as an idiopathic left ventricular failure with reduced ejection fraction (EF <45%) that affects women in the last month of pregnancy or in the months after giving birth. The pathophysiology remains elusive, resulting in complications with varied severity; one of the most concerning complications is thromboembolism, specifically pulmonary embolism (PE). The purpose of this study was to characterize and evaluate the real-world prevalence, predictors, and outcomes of PE in PPCM. Methods The data were derived from the National Inpatient Sample (NIS) database from January 2016 to December 2019. The primary outcomes assessed were baseline and hospital admission characteristics and comorbidities for patients with PPCM with or without PE. Outcomes for PPCM patients with PE and predictors of mortality for PPCM were also analyzed. Results PE developed in 105 of 4,582 patients with PPCM (2.3%). Patients with PPCM and PE had longer hospital stays (10.86 days ± 1.4 vs. 5.73 ± 0.2 days, p = 0.001) and total charges ($169,487 ± $39,628 vs. $86,116 ± $3,700, p = 0.001). Patients with PE had a higher burden of coagulopathy (13.3% vs. 3.0%, p = 0.01), intracardiac thrombus (6.7% vs. 1.6%, p = 0.01), and iron deficiency anemia (21.0% vs. 12.6%, p = 0.01). Patients without PE were found to have a higher burden of preeclampsia (14.7% vs. 1.9%, p = 0.01) and obstructive sleep apnea (5.4% vs. 1.0%, p = 0.045). Predictors of mortality in patients with PPCM included cardiogenic shock (aOR 13.42, 95% CI 7.50-24.03, p = 0.05), PE (aOR 6.60, 95% CI 2.506-17.39, p = 0.05), non-ST-elevation myocardial infarction (NSTEMI; aOR 3.57, 95% CI 1.35-9.44, p = 0.05), chronic kidney disease (aOR 3.23, 95% CI 1.68-6.22, p = 0.05), and atrial fibrillation (aOR 2.57; 95% CI 1.25-5.30, p = 0.05). Conclusion Although an uncommon complication, PE in PPCM demonstrates an association with higher mortality and financial burden. Along with PE, we found predictors of mortality in PPCM to include atrial fibrillation, NSTEMI, chronic kidney disease, and cardiogenic shock.

Normative Values of Echocardiographic Chamber Size and Function in Older Healthy Adults: The Multi-Ethnic Study of Atherosclerosis.

BACKGROUND: Echocardiographic (2-dimensional echocardiography) thresholds indicating disease or impaired functional status compared with normal physiological aging in individuals aged ≥65 years are not clearly defined. In the present study, we sought to establish standard values for 2-dimensional echocardiography parameters related to chamber size and function in older adults without cardiopulmonary or cardiometabolic conditions. METHODS: In this cross-sectional study of 3032 individuals who underwent 2-dimensional echocardiography at exam 6 in the MESA (Multi-Ethnic Study of Atherosclerosis), 608 participants fulfilled our inclusion criteria of healthy aging, with normative values defined as the mean ± 1.96 standard deviation and compared across sex and race and ethnicity. Functional status measures included NT-proBNP (N-terminal pro-B-type natriuretic peptide), 6-minute walk distance, and Kansas City Cardiomyopathy Questionnaire. Prognostic performance using MESA cutoffs was compared with established guideline cutoffs using time-to-event analysis. RESULTS: The normative aging cohort (69.5±7.0 years, 46.2% male, 47.5% White) had lower NT-proBNP, higher 6-minute walk distance, and higher (better) Kansas City Cardiomyopathy Questionnaire summary values. Women had significantly smaller chamber sizes and better biventricular systolic function. White participants had the largest chamber dimensions, whereas Chinese participants had the smallest, even after adjustment for body size. Current guidelines identified 81.6% of healthy older adults in MESA as having cardiac abnormalities. CONCLUSIONS: Among a large, diverse group of healthy older adults, we found significant differences in cardiac structure and function by sex and race/ethnicity, which may signal sex-specific cardiac remodeling with advancing age. It is crucial for existing guidelines to consider the observed and clinically significant differences in cardiac structure and function associated with healthy aging. Our study highlights that existing guidelines, which grade abnormalities in echocardiographic cardiac chamber size and function based on younger individuals, may not adequately address the anticipated changes associated with normal aging.

Unlocking Health Literacy: The Ultimate Guide to Hypertension Education From ChatGPT Versus Google Gemini.

Background Google Gemini (Google, Mountain View, CA) represents the latest advances in the realm of artificial intelligence (AI) and has garnered attention due to its capabilities similar to the increasingly popular ChatGPT (OpenAI, San Francisco, CA). Accurate dissemination of information on common conditions such as hypertension is critical for patient comprehension and management. Despite the ubiquity of AI, comparisons between ChatGPT and Gemini remain unexplored. Methods ChatGPT and Gemini were asked 52 questions derived from the American College of Cardiology's (ACC) frequently asked questions on hypertension, following a specified prompt. Prompts included: no prompting (Form 1), patient-friendly prompting (Form 2), physician-level prompting (Form 3), and prompting for statistics/references (Form 4). Responses were scored as incorrect, partially correct, or correct. Flesch-Kincaid (FK) grade level and word count were recorded. Results Across all forms, scoring frequencies were as follows: 23 (5.5%) incorrect, 162 (38.9%) partially correct, and 231 (55.5%) correct. ChatGPT showed higher rates of partially correct answers than Gemini (p = 0.0346). Physician-level prompts resulted in a higher word count across both platforms (p < 0.001). ChatGPT showed a higher FK grade level (p = 0.033) in physician-friendly prompting. Gemini exhibited a significantly higher mean word count (p < 0.001); however, ChatGPT had a higher FK grade level across all forms (p > 0.001). Conclusion To our knowledge, this study is the first to compare cardiology-related responses from ChatGPT and Gemini, two of the most popular AI chatbots. The grade level for most responses was collegiate level, which was above average for the National Institutes of Health (NIH) recommendations, but on par with most online medical information. Both chatbots responded with a high degree of accuracy, with inaccuracies being rare. Therefore, it is reasonable that cardiologists suggest either chatbot as a source of supplementary education.

Increase in acute mastoiditis at the end of the COVID-19 pandemic.

PURPOSE: Common respiratory infections were significantly reduced during the COVID-19 pandemic due to general protective and hygiene measures. The gradual withdrawal of these non-pharmaceutical interventions (NPI) was associated with a notable increase in these infections, particularly in pediatric and adult otorhinolaryngology. The aim of this retrospective monocentric study was to evaluate the impact of NPI during the COVID-19 pandemic on the incidence and severity of acute mastoiditis (AM). METHODS: Pre-pandemic clinical data of AM cases from 2011 to 2019 were compared with infection counts from January 2020 to June 2023 for seasonal periodicity, age-specific differences, pathogens, and complication rates in a German third-level hospital. RESULTS: Out of 196 patients with AM 133 were children, the majority between 1 and 5 years of age. Complications of AM, such as meningitis, brain abscess, and sinus vein thrombosis, were more common in adults (87%) than in children (17%). Morbidity and mortality rates were similar before, during and after the pandemic. Pneumococci were the most common pathogen in both age groups, with a post-pandemic cumulation of Streptococcus pyogenes infections in children. While pre-pandemic cases clustered in spring, seasonality was absent in all age groups during the main phase of the pandemic. The cessation of NPI caused a steep rise in AM cases in both age groups starting from December 2022. CONCLUSION: NPI during the COVID-19 pandemic reduced the incidence of AM. Their reversal led to a substantial increase in the incidence of AM during the post-pandemic period, which may be due to a general increase in viral respiratory infections and an insufficiently trained immune system.

HLA reduction of human T cells facilitates generation of immunologically multicompatible cellular products.

ABSTRACT: Adoptive cellular therapies have shown enormous potential but are complicated by personalization. Because of HLA mismatch, rejection of transferred T cells frequently occurs, compromising the T-cell graft's functionality. This obstacle has led to the development of HLA knock-out (KO) T cells as universal donor cells. Whether such editing directly affects T-cell functionality remains poorly understood. In addition, HLA KO T cells are susceptible to missing self-recognition through natural killer (NK) cells and lack of canonical HLA class I expression may represent a safety hazard. Engineering of noncanonical HLA molecules could counteract NK-cell recognition, but further complicates the generation of cell products. Here, we show that HLA KO does not alter T-cell functionality in vitro and in vivo. Although HLA KO abrogates allogeneic T-cell responses, it elicits NK-cell recognition. To circumvent this problem, we demonstrate that selective editing of individual HLA class I molecules in primary human T cells is possible. Such HLA reduction not only inhibits T-cell alloreactivity and NK-cell recognition simultaneously, but also preserves the T-cell graft's canonical HLA class I expression. In the presence of allogeneic T cells and NK cells, T cells with remaining expression of a single, matched HLA class I allele show improved functionality in vivo in comparison with conventional allogeneic T cells. Since reduction to only a few, most frequent HLA haplotypes would already be compatible with large shares of patient populations, this approach significantly extends the toolbox to generate broadly applicable cellular products.

Reference Values for Indexed Echocardiographic Chamber Sizes in Older Adults: The Multi-Ethnic Study of Atherosclerosis.

BACKGROUND: Normalization of echocardiographic chamber measurements for body surface area may result in misclassification of individuals with obesity or sarcopenia. Normalization for alternative measures of body size may be preferable, but there remains a dearth of information on their normative values and association with cardiovascular function metrics. METHODS AND RESULTS: A total of 3032 individuals underwent comprehensive 2-dimensional echocardiography at Exam 6 in MESA (Multi-Ethnic Study of Atherosclerosis). In the subgroup of 608 individuals free of cardiopulmonary disease (69.5±7.0 years, 46% male, 48% White, 17% Chinese, 15% Black, 21% Hispanic), normative values were derived for left and right cardiac chamber measurements across a variety of ratiometric (body surface area, body mass index, height) and allometric (height1.6, height2.7) scaling parameters. Normative upper and lower reference values were provided for each scaling parameter stratified across age groups, sex, and race or ethnicity. Among scaling parameters, body surface area and height were associated with the least variability across race and ethnicity categories and height2.7 was associated with the least variability across sex categories. CONCLUSIONS: In this diverse cohort of community-dwelling older adults, we provide normative values for common echocardiographic parameters across a variety of indexation methods.

Plasma proteomic signature of human longevity.

The identification of protein targets that exhibit anti-aging clinical potential could inform interventions to lengthen the human health span. Most previous proteomics research has been focused on chronological age instead of longevity. We leveraged two large population-based prospective cohorts with long follow-ups to evaluate the proteomic signature of longevity defined by survival to 90 years of age. Plasma proteomics was measured using a SOMAscan assay in 3067 participants from the Cardiovascular Health Study (discovery cohort) and 4690 participants from the Age Gene/Environment Susceptibility-Reykjavik Study (replication cohort). Logistic regression identified 211 significant proteins in the CHS cohort using a Bonferroni-adjusted threshold, of which 168 were available in the replication cohort and 105 were replicated (corrected p value <0.05). The most significant proteins were GDF-15 and N-terminal pro-BNP in both cohorts. A parsimonious protein-based prediction model was built using 33 proteins selected by LASSO with 10-fold cross-validation and validated using 27 available proteins in the validation cohort. This protein model outperformed a basic model using traditional factors (demographics, height, weight, and smoking) by improving the AUC from 0.658 to 0.748 in the discovery cohort and from 0.755 to 0.802 in the validation cohort. We also found that the associations of 169 out of 211 proteins were partially mediated by physical and/or cognitive function. These findings could contribute to the identification of biomarkers and pathways of aging and potential therapeutic targets to delay aging and age-related diseases.

Height and body surface area versus wall stress for stratification of mid-term outcomes in ascending aortic aneurysm.

Objectives: Current diameter-based guidelines for ascending thoracic aortic aneurysms (aTAA) do not consistently predict risk of dissection/rupture. ATAA wall stresses may enhance risk stratification independent of diameter. The relation of wall stresses and diameter indexed to height and body surface area (BSA) is unknown. Our objective was to compare aTAA wall stresses with indexed diameters in relation to all-cause mortality at 3.75 years follow-up. Methods: Finite element analyses were performed in a veteran population with aortas ≥ 4.0 cm. Three-dimensional geometries were reconstructed from computed tomography with models accounting for pre-stress geometries. A fiber-embedded hyperelastic material model was applied to obtain wall stress distributions under systolic pressure. Peak wall stresses were compared across guideline thresholds for diameter/BSA and diameter/height. Hazard ratios for all-cause mortality and surgical aneurysm repair were estimated using cause-specific Cox proportional hazards models. Results: Of 253 veterans, 54 (21 %) had aneurysm repair at 3.75 years. Indexed diameter alone would have prompted repair at baseline in 17/253 (6.7 %) patients, including only 4/230 (1.7 %) with diameter < 5.5 cm. Peak wall stresses did not significantly differ across guideline thresholds for diameter/BSA (circumferential: p = 0.15; longitudinal: p = 0.18), but did differ for diameter/height (circumferential: p = 0.003; longitudinal: p = 0.048). All-cause mortality was independently associated with peak longitudinal stresses (p = 0.04). Peak longitudinal stresses were best predicted by diameter (c-statistic = 0.66), followed by diameter/height (c-statistic = 0.59), and diameter/BSA (c-statistic = 0.55). Conclusions: Diameter/height improved stratification of peak wall stresses compared to diameter/BSA. Peak longitudinal stresses predicted all-cause mortality independent of age and indexed diameter and may aid risk stratification for aTAA adverse events.

Should the Left Atrial Appendage Closure (LAAC) Technique Be the Main Form of Stroke Prevention in Patients With Long-Standing Persistent or Permanent Atrial Fibrillation?

Currently, oral anticoagulants are considered the gold standard for stroke prevention in patients with atrial fibrillation. Despite the efficacy of oral anticoagulants in reducing stroke incidence, patients are at risk of developing adverse reactions such as excessive bleeding and bruising, and can also have drug-drug interactions. In the early 2000s, a minimally invasive technique called the left atrial appendage closure emerged as an alternative for stroke prevention in atrial fibrillation patients who could not tolerate oral anticoagulants. Despite the success of the left atrial appendage closure, practitioners still opt for medication therapy and are reluctant to advocate for this procedure. Given the adverse effects of oral anticoagulants, physicians should question if this is the appropriate method of stroke prevention in long-standing persistent or permanent atrial fibrillation patients. This case report investigates an 82-year-old Middle Eastern male in the United States with long-standing persistent atrial fibrillation who underwent a left atrial appendage closure due to recurrent bleeding on oral anticoagulants. In addition, there will be further discussion on the appropriate method of stroke prevention in similar patients.

How to Treat a Cyclist's Nodule?-Introduction of a Novel, ICG-Assisted Approach.

BACKGROUND: Perineal nodular induration (PNI) is a benign proliferation of the soft tissue in the perineal region that is associated with saddle sports, especially road cycling. The etiology has not been conclusively clarified; however, repeated microtrauma to the collagen and subcutaneous fat tissue by pressure, vibration and shear forces is considered a mechanical pathomechanism. In this context, chronic lymphedema resulting in the development of fibrous tissue has been suggested as an etiological pathway of PNI. The primary aim of this study was to introduce and elucidate a novel operative technique regarding PNI that is assisted by indocyanine green (ICG). In order to provide some context for this approach, we conducted a comprehensive review of the existing literature. This dual objective aimed to contribute to the existing body of knowledge while introducing an innovative surgical approach for managing PNI. METHODS: We reviewed publications relating to PNI published between 1990 and 2023. In addition to the thorough review of the literature, we presented our novel surgical approach. We described how this elaborate approach for extensive cases of PNI involves surgical excision combined with tissue doubling and intraoperative ICG visualization for exact lymphatic vessel obliteration to minimize the risk of recurrence based on the presumed context of lymphatic congestion. RESULTS: The literature research yielded 16 PubMed articles encompassing 23 cases of perineal nodular induration (PNI) or cyclist's nodule. Of these, 9 cases involved females, and 14 involved males. Conservative treatment was documented in 7 cases (30%), while surgical approaches were reported in 16 cases (70%). Notably, a limited number of articles focused on histopathological or radiological characteristics, with a shortage of structured reviews on surgical treatment options. Only two articles provided detailed insights into surgical techniques. Similarly to the two cases of surgical intervention identified in the literature research, the post-operative recovery in our ICG assisted surgical approach was prompt, meaning a return to cycling was possible six weeks after surgery. At the end of the observation period (twelve months after surgery), regular scar formation and no signs of recurrence were seen. CONCLUSION: We hope that this article draws attention to the condition of PNI in times of increasing popularity of cycling as a sport. We aimed to contribute to the existing body of knowledge through our thorough review of the existing literature while introducing an innovative surgical approach for managing PNI. Due to the successful outcome, the combination of tissue doubling, intraoperative ICG visualization and postoperative negative wound therapy should be considered as a therapeutic strategy in cases of large PNI.

A critical moment in machine learning in medicine: on reproducible and interpretable learning.

Over the past two decades, advances in computational power and data availability combined with increased accessibility to pre-trained models have led to an exponential rise in machine learning (ML) publications. While ML may have the potential to transform healthcare, this sharp increase in ML research output without focus on methodological rigor and standard reporting guidelines has fueled a reproducibility crisis. In addition, the rapidly growing complexity of these models compromises their interpretability, which currently impedes their successful and widespread clinical adoption. In medicine, where failure of such models may have severe implications for patients' health, the high requirements for accuracy, robustness, and interpretability confront ML researchers with a unique set of challenges. In this review, we discuss the semantics of reproducibility and interpretability, as well as related issues and challenges, and outline possible solutions to counteracting the "black box". To foster reproducibility, standard reporting guidelines need to be further developed and data or code sharing encouraged. Editors and reviewers may equally play a critical role by establishing high methodological standards and thus preventing the dissemination of low-quality ML publications. To foster interpretable learning, the use of simpler models more suitable for medical data can inform the clinician how results are generated based on input data. Model-agnostic explanation tools, sensitivity analysis, and hidden layer representations constitute further promising approaches to increase interpretability. Balancing model performance and interpretability are important to ensure clinical applicability. We have now reached a critical moment for ML in medicine, where addressing these issues and implementing appropriate solutions will be vital for the future evolution of the field.

Updates in Surgical Oncology.

New knowledge and data can influence the treatment options of dogs and cats affected by neoplasms. Partial limb amputation with the use of a prosthesis is possible in dogs. Newer studies attempt to define better and understand the complications and limb function associated with this approach. Limb sparing is an alternative to amputation, and three-dimensional printing allows the manufacturing of personalized endoprostheses. Finally, the recommended approach for the excision of cutaneous mast cell tumors (MCTs) is with proportional margins. In dogs, grade shifting might have occurred when removing a recurrent MCT or soft tissue sarcoma.

Camel milk products beyond yoghurt and fresh milk: challenges, processing and applications.

Camel (Camelus dromedarius and (Camelus bactrianus) are commonly domesticated in the arid and semi-arid regions because they are well adapted to live in harsh climatic conditions. Camel milk is widely consumed in these regions due to its high nutritional value and medicinal properties. It is rich in protein, minerals and vitamins. Moreover, it possesses therapeutic properties such as anti-microbial, anti-oxidants, anti-viral and anti-cancer. Camel milk can be processed into value added products with the aim of extending shelf life and diversifying its usage. However, there are various challenges experienced in processing of camel milk products. This study aims at reviewing published literature on camel milk products processing, processing challenges, the available solutions and applications. To achieve these aims, literature search was carried out using narrative methodology. Literature review provided information concerning processing of camel milk products, the challenges, how to overcome these processing challenges and applications. From this review of literature on camel milk products it can be concluded that it's possible to process these products with some challenges but scientific and technological solutions are available that are improving over time.

First principle study of ATiO[Formula: see text] (A=Ti,Sr) materials for photovoltaic applications.

CONTEXT: The study investigates the impact of Hubbard U correction and spin-orbit coupling (SOC) on the structural, mechanical, electronic, and optical properties of Ti[Formula: see text]O[Formula: see text] and SrTiO[Formula: see text] compounds. The research is motivated by the potential applications of these materials in photovoltaics, with a focus on understanding their properties for such use. The ductility, ionicity, and mechanical stability of both compounds at zero pressure are assessed, indicating their potential as resilient materials. Also, the compounds display high refractive indices and absorption coefficients, indicating their suitability for solar harvesting applications. The predicted bandgaps align primarily with the UV-Vis areas of the electromagnetic spectrum, highlighting their potential in this domain. METHODS: Computational techniques employed in this study are density functional theory (DFT) with and without spin-orbit coupling, as well as DFT+U methods, implemented using the Quantum ESPRESSO (QE) package. The study adopts the Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional, while employing a plane-wave basis set with an energy cutoff of 50 Ry for wavefunctions and 500 Ry for charge density.

[Strength of the taper junction of modular revision hip stems : The influence of contamination of the taper junction and the joining condition on the relative motion and pull-off force between the stem and neck part of the MRP prosthesis]. / Festigkeit der Konusverbindung modularer Revisionshüftschäfte : Einfluss der Verunreinigung der Konusverbindung und der Fügebedingung auf die Relativbewegung und Abzugskraft zwischen Schaft und Halsteil der MRP-Prothese.

INTRODUCTION: In revision surgery, modular implant components allow the surgeon to tailor the characteristics of the implant to the bone situation. Relative motion can occur at the tapered modular connection, leading to fretting corrosion and subsequent biological reactions, particularly due to poor assembly and contamination of the tapered connection. The aim of this study was to demonstrate whether incomplete assembly and inadvertent contamination of the modular taper causes a change in junction strength. MATERIAL AND METHODS: Modular taper junctions between the neck and the stem (n = 48) were divided into seven groups that differed with respect to contamination (native, contaminated, cleaned) and assembly conditions (secured, pre-tensioned and secured). Contamination was achieved by a combination of porcine bone particles and bovine blood. For each group, the number of rotations of the torque limiter while securing the conical connection was recorded. The implants were subjected to cyclic loading. DIC was used to determine neck rotation, micromotion and axial subsidence. Loosening torque of the locking screw and pull-off forces were measured as an equivalent of residual taper junction strength. RESULTS: Contamination of the taper junction, especially in combination with improper assembly of the components, significantly increased the rotation (35.3 ± 13.7° vs. 2.4 ± 4.4°; p <0.001), micromotion (67.8 ± 16.9 µm vs. 5.1 ± 12.1 µm, p <0.001) and axial subsidence (­34.1 ± 16.9 µm vs. 4.3 ± 10.9 µm; p <0.001) of the neck relative to the stem. CONCLUSION: Intra-operatively, contamination of the taper surface can be identified by the need for multiple turns when tightening the locking screw. Correct cleaning with the new taper cleaning instrument and complete assembly with pre-tensioning may reduce the risk of early failure and fatigue fracture of the modular taper connection.

Regional outcome disparities in German head and neck cancer patients: Shorter survival in Eastern Germany.

INTRODUCTION: Demographics are important prognostic factors in malignant diseases. A nationwide analysis concerning the prognostic impact of demographics in head and neck cancer (HNC) patients (HNCP) has not been performed previously. METHODS: A retrospective analysis of data from the Center for Cancer Registry Data (ZfKD) and the Federal Statistical Office (Destatis) between 2002 and 2017 was performed. A total of 212'920 HNCP were included. Incidence, tumor stage, age development, sex distribution, age-, residence-, and diagnosis-time-specific survival were examined. RESULTS: Mean age of HNCP increased more rapidly than in the general population (slope coefficient: 0.29 vs. 0.20; p < 0.0001). Higher age and male sex were associated with a worse prognosis. Whereas overall survival (OS) increased from the early to the later observation period for HNCP <70 years, no OS improvement for HNCP >70 years was found. Furthermore, an OS disadvantage was observed for East Germany compared to West Germany (median 47 vs. 60 months; p < 0.0001). This disparity was associated with a disproportionately high ratio of men in East Germany (men/women: 4.4 vs. 3.1; p < 0.0001) and a lower mean age (61 vs. 63 years; p < 0.0001). In addition to stage, age and sex, residence in East Germany were confirmed as an independent factor for OS in a multivariate analysis. CONCLUSION: Finally, three decades after the German reunion, a survival disadvantage for patients in East Germany still exists. This discrepancy may be a result of socioeconomic disparities.

Normative Values of Echocardiographic Chamber Size and Function in Older Healthy Adults: The Multi-Ethnic Study of Atherosclerosis.

Background: Echocardiographic (2DE) thresholds indicating disease or impaired functional status compared to normal physiologic aging in individuals ≥ 65 years are not clearly defined. In the present study, we sought to establish standard values for 2DE parameters related to chamber size and function in older adults without cardiopulmonary or cardiometabolic conditions. Methods: In this cross-sectional study of 3032 individuals who underwent 2DE at Exam 6 in the Multi-Ethnic Study of Atherosclerosis (MESA), 608 participants fulfilled our inclusion criteria, with normative values defined as the mean value ± 1.96 standard deviations and compared across sex and race/ethnicity. Functional status measures included NT-proBNP, 6-minute walk distance [6MWD], and Kansas City Cardiomyopathy Questionnaire [KCCQ]. Prognostic performance using MESA cutoffs was compared to established guideline cutoffs using time-to-event analysis. Results: Participants meeting our inclusion criteria (69.5 ± 7.0 years, 46.2% male, 47.5% White) had lower NT-proBNP, higher 6MWD, and higher (better) KCCQ summary values. Women had significantly smaller chamber sizes and better biventricular systolic function. White participants had the largest chamber dimensions, while Chinese participants had the smallest, even after adjustment for body size. Current guidelines identified 81.6% of healthy older adults in MESA as having cardiac abnormalities. Conclusions: Among a large, diverse group of healthy older adults, we found significant differences in cardiac structure and function across sexes and races/ethnicities, which may signal sex-specific cardiac remodeling with advancing age. It is crucial for existing guidelines to consider the observed and clinically significant differences in cardiac structure and function associated with healthy aging. Our study highlights that existing guidelines, which grade abnormalities in echocardiographic cardiac chamber size and function based on younger individuals, may not adequately address the anticipated changes associated with normal aging.