Science Progress最新文献

ObjectivePulmonary-to-aortic diameter ratio (P/A) correlates with pulmonary hypertension (PH), which is linked to adverse outcomes. Our aim was to evaluate the impact of the P/A ratio, measured using computed tomography (CT), on adverse postoperative outcomes in patients undergoing transcatheter aortic valve implantation (TAVI).MethodsThis study included 387 patients with aortic valve disease who underwent TAVI between January 2018 and June 2024. The clinical endpoint was the composite outcome of all-cause mortality and postoperative hospitalization for heart failure. The cut-off value for the P/A ratio was obtained by analyzing the receiver operating characteristic (ROC) curve. Cox proportional hazards models were used to examine the association between the P/A ratio and the composite outcome, with subsequent subgroup and sensitivity analyses.ResultsThe median follow-up time was 19 months [interquartile range (IQR): 1.00-59.0], and a composite outcome occurred in 14% of patients in this study. A P/A ratio of 0.84 was identified as the optimal cut-off value. Compared with the low P/A group, the high P/A group had a higher proportion of females and patients with diabetes, higher triglyceride levels, and higher systolic pulmonary artery pressure (sPAP) levels. Multivariable Cox analysis confirmed that a high P/A ratio [hazard ratio (HR): 1.96, 95% confidence interval (CI): 1.03-3.72; p = 0.04] was associated with the composite outcome. Subgroup and sensitivity analyses yielded consistent results.ConclusionsThe P/A ratio measured using CT may serve as a novel prognostic factor in patients undergoing TAVI. A high P/A ratio (≥ 0.84) is an independent risk factor for the composite outcome.

ObjectiveKnee orthoses assist patients with joint instability, yet many passive designs provide limited energy dissipation and flexion-load regulation during high-demand activities. This study designed and validated a compact three-spring shock-absorption mechanism to provide quasi-passive flexion resistance, improve energy absorption, and redistribute loads in knee orthoses.MethodsA mechanical design and validation study was conducted combining analytical modeling, finite-element simulation, and pilot functional testing. The mechanism integrates two compression springs and one tension spring housed in an aluminum frame. Finite-element simulations (ANSYS Explicit Dynamics^®) evaluated deformation, absorbed energy, and von Mises stress under dynamic loading over a 0-70° motion range, and were calibrated using experimental compression/tension tests of single and paired springs. Three functional prototypes were fabricated and evaluated by three adult volunteers using one-leg rise and deep-squat tasks, with perceived assistance recorded on a 100-mm Visual Analogue Scale (VAS) under institutional ethics approval.ResultsSimulated and experimental endpoint force and total deformation (L₀ - Lf) showed close agreement, with relative deviations below 3%. For the evaluated configuration, the orthosis generated an estimated total passive flexion resistance of 70.54 Nm for two modules, corresponding to a case-specific 48.22% reduction in required flexion torque when referenced to a representative post-ACLR peak torque (146.30 Nm). Peak stresses remained below the yield strength of 6061-T6 aluminum, while the beam-base interface was identified as the durability-critical region. Functional testing yielded mean VAS scores of 36.67 ± 2.89 (one-leg rise) and 41.67 ± 5.77 (deep squat), indicating moderate perceived assistance.ConclusionsThe proposed multi-spring mechanism provides measurable quasi-passive resistance and withstands conservative high-flexion loading, supporting its feasibility as a compact assistive concept. These proof-of-concept results motivate further work on fatigue/wear assessment, multi-objective optimization, and larger clinical studies with objective functional outcomes.

ObjectiveTo compare the effectiveness, safety, and cost outcomes of brand-name febuxostat (feburic) and generic febuxostat (feuri) in patients with hyperuricemia or gout in a real-world clinical setting.MethodsWe conducted a retrospective cohort study using electronic medical records from Taichung Veterans General Hospital between November 2021 and December 2023. Adult patients with hyperuricemia or gout who initiated febuxostat therapy and had no prior urate-lowering treatment in the preceding 3 months were included. Serum uric acid levels were assessed at baseline, 3 months, and the final follow-up. Propensity score matching (1:1) was applied to balance baseline demographic, clinical, laboratory, cardiovascular, and renal characteristics. Clinical outcomes, laboratory parameters, and medication costs were compared between groups.ResultsBoth feuri and feburic were associated with significant reductions in serum uric acid levels after 3 months of treatment. At the 3-month assessment, the mean serum uric acid level was modestly lower in the feuri group (5.41 ± 2.06 mg/dL) than in the feburic group (5.75 ± 2.12 mg/dL; P = .001). At the final follow-up, serum uric acid levels remained numerically lower in the feuri group, although the difference was not statistically significant (P = .07). The feuri group was prescribed a lower final daily dose, which was associated with lower annual medication costs. The proportions of patients achieving recommended uric acid goals were similar between groups, suggesting broadly comparable clinical effectiveness in routine practice. After propensity score matching (n = 486 pairs), no significant differences were observed between groups in cardiovascular, renal, or overall safety outcomes.ConclusionsThis real-world study suggests that generic febuxostat is associated with safety outcomes comparable to those of the brand-name formulation and may be prescribed at lower doses and lower medication costs in routine clinical practice.

Esophageal melanosis is an uncommon condition characterized by melanin deposition in the esophageal mucosa. We report the case of a female in her late 40s with systemic lupus erythematosus and Sjögren's syndrome, in whom an incidental hyperpigmented lesion was identified in the mid-esophagus during endoscopy performed for iron-deficiency anemia. Histopathological examination confirmed melanocytosis without evidence of dysplasia or malignancy. Although its etiology remains unclear, esophageal melanosis has been linked to chronic mucosal inflammation or injury, which may be triggered by autoimmune alterations. Further studies are warranted to clarify this potential association.

A tracheoesophageal fistula (TEF) is an abnormal connection between the trachea and esophagus, which is an intractable clinical challenge associated with a poor prognosis and a high mortality. We report the successful closure of a complex, large-diameter TEF in a male patient in his late 60s following radical esophagectomy, with initial surgical and esophagoscopic interventions considered unfeasible. A tracheal stent was placed to cover the fistula as a bridging therapy, followed by definitive closure using an over-the-scope clip (OTSC). The tracheal stent was removed at the 5-month follow-up, and no serious complications were observed during or after endoscopic management. For complex TEFs that are not amenable to surgical repair or esophagoscopic closure, tracheal stent placement serves as a bridging therapy, thereby providing a window for subsequent interventions. The combined strategy of tracheal stenting with the OTSC provides a minimally invasive and highly effective treatment option for complex TEFs through multidisciplinary collaboration.

Colorectal cancer remains a major global health concern, highlighting the critical importance of effective colonoscopy, whose success depends on high-quality bowel preparation. Inadequate preparation is common and leads to prolonged procedure, and missed polyps and adenomas. It is important to recognize that not all individuals can attain adequate bowel preparation through a uniform regimen. Various risk factors influencing bowel preparation quality have been reported, and different laxative regimens each present distinct advantages and limitations. Understanding these elements can help improve patient bowel preparation outcomes. This is a narrative review. This article attempts to summarize available clinical trials and evidence regarding strategies to optimize bowel preparation for individuals.

ObjectiveTo estimate the prevalence of human papillomavirus (HPV) infection among males in Jinshan District, Shanghai, China.MethodsStudy design: single-center, retrospective cross-sectional study.

Setting: Tinglin Hospital, Jinshan District, Shanghai, China.

Participants: 116 males aged 22-71 years from outpatient, inpatient, and routine physical examination settings.

Outcomes: overall HPV prevalence, age-specific prevalence, and genotype distribution (high-risk and low-risk).ResultsWe first describe the overall and age-specific prevalence, followed by genotype distribution and the pattern of single versus multiple infections. A total of 116 males aged 22 to 71 years old were enrolled for investigation. The overall HPV infection rate was 31.90% (37/116). The infection rates of different HPV subtypes in various age groups were listed as follows: 12% (3/25) for the 22-30 age group, 27.59% (8/29) for the 31-40 age group, 50% (18/36) for the 41-50 age group, 16.67% (3/18) for the 51-60 age group, and 62.5% (5/8) for the over 60 age group. Among the infected individuals, 27 out of 116 (23.28%) suffered from single subtype infections, while 8 individuals (6.90%) endured dual infections, and 2 individuals (1.72%) had three or more subtypes detected. High-risk HPVs accounted for 30.17%, with the highest infection rates observed in HPVs including HPV-53, HPV-58, HPV-52, HPV-16, and HPV-31. In comparison, low-risk HPVs accounted for 12.93%, with the highest infection rates seen in HPVs including HPV-6, HPV-81, and HPV-11. Apart from that, HPVs such as HPV-18, HPV-59, HPV-73, HPV-70 and HPV-83 were not detected in any of the specimens.ConclusionMales are predominantly infected with a single-subtype HPV infection. The infection rate is highest in the age group of 60 and above, while the infection rate is the lowest in the age group of 22-30 years. It is essential to formulate corresponding strategies and screening plans for the elderly over 60 years to lower or prevent the risk of HPV infection.

When the demand for public health care increases, governments often prioritize citizens over foreign nationals. In South Africa, limited resources and socio-economic inequalities pose unique challenges to epidemic control. The overcrowding and increasing demand for public healthcare have led to protests by some community groups, which have led to the denial of healthcare to migrants. Denying treatment to some infected individuals has the propensity to lead to an increase in the size of an epidemic. We introduce a novel epidemiological model that incorporates health care denial as a dynamic factor influencing the transmission of COVID-19. It incorporates healthcare denial as a key parameter influencing the progression and recovery rates of infections. The study presents a novel framework for understanding the intersection of healthcare access denial and the transmission dynamics of COVID-19. While much of the existing literature has focused on the direct effects of healthcare interventions on pandemic control, this research uniquely emphasizes the role that restricted access to healthcare services, whether due to policy decisions, resource shortages, or system inefficiencies, can exacerbate the spread of infectious diseases. The treatment class of the model is partitioned to account for individuals denied treatment at public healthcare facilities. Analytical results establish conditions for the existence and stability of both disease-free and endemic equilibria, with the basic reproduction number R₀ explicitly derived to quantify transmission potential under varying healthcare access scenarios. Sensitivity analysis reveals that increasing denial of care can significantly elevate R₀, resulting in higher infection peaks, prolonged epidemic duration and greater cumulative mortality. Numerical simulations further illustrate the non-linear relationship between treatment accessibility and outbreak severity. The findings highlight that equitable healthcare provision is not only a public health necessity but also a critical determinant for reducing the COVID-19 burden. Policy implications stress the integration of inclusive healthcare strategies to ensure epidemic resilience and minimize transmission risks, especially in vulnerable populations. Strategies that will accommodate every infected person who goes to the hospital for treatment should be adopted to reduce the disease burden.

IntroductionHeparin-induced thrombocytopenia (HIT) is a severe complication of heparin treatment, characterized by low platelet counts and heightened thrombotic risk. Blood urea nitrogen (BUN), which serves as an indicator of both renal function and illness severity, has been associated with poor outcomes in different contexts. However, its association with mortality in HIT remains poorly understood. Our study aimed to explore this relationship in critically ill patients with HIT.MethodsThis study was a retrospective cohort analysis utilizing the MIMIC-IV 3.1 database from 2008 to 2019. Patients with HIT were pinpointed through ICD codes. Those without BUN data or whose intensive care unit (ICU) admission was not their first were excluded. The main outcome measured was all-cause mortality, evaluated at multiple time points. The associations were examined using multivariate Cox regression models and Kaplan-Meier survival analysis.ResultsThe research encompassed 246 individuals with HIT (average age 66.2 years, 54.9% male). BUN levels showed a significant association with all-cause mortality during the hospital stay (HR 1.01, 95% CI 1.01-1.02, p = 0.001), within 30 days (HR 1.01, 95% CI 1.01-1.02, p < 0.001), within 90 days (HR 1.01, 95% CI 1.01-1.02, p < 0.001), and within 365 days (HR 1.01, 95% CI 1.01-1.02, p < 0.001). Quartile analysis revealed that the highest BUN quartile (Q4) was associated with the greatest mortality risk compared to the lowest quartile (Q1) at all time points. Kaplan-Meier and restricted cubic spline analyses corroborated these results, indicating a linear relationship between BUN and mortality.ConclusionElevated BUN levels were significantly associated with higher mortality rates among HIT patients in the ICU. Monitoring BUN levels may help identify patients at greater risk and inform clinical choices. Further research is warranted to elucidate the underlying mechanisms and possible treatments.

ObjectiveThe use of aspirin in patients undergoing open tracheostomy is an issue for which there is still no clear conclusion. This uncertainty leads surgeons to make decisions based on the risks and benefits of continuing versus discontinuing aspirin. Therefore, this study aims to investigate complications related to aspirin use. The primary outcome was bleeding complications, while other complications were secondary outcomes.MethodsThis was a retrospective study compiling data from patients who underwent open tracheostomy at the Department of Otolaryngology, Faculty of Medicine, Chulalongkorn university and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, between January 2019 and December 2023. Demographic data, medical conditions, indications for tracheostomy, surgeon characteristics, operative time, aspirin use status, and complications were reviewed.ResultsThere were 47 patients in total in this study: 15 patients in the aspirin continuation group and 32 patients in the aspirin discontinuation group. In the aspirin continuation group, there were no major or minor bleeding events. In the discontinuation group, there were two cases of major bleeding and two cases of minor bleeding (an incidence of 6.3% for each), although the differences observed were not statistically significant. There were no other complications that showed statistically significant differences between the two groups.ConclusionThis study has shown that low-dose aspirin (81 mg) does not increase the risk of bleeding or other complications in patients who undergo open tracheostomy. These results support that the continuation of aspirin may be safe in patients undergoing this procedure.