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1.
IEEE Trans Med Imaging ; PP2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607705

RESUMO

With the widespread interest and uptake of super-resolution ultrasound (SRUS) through localization and tracking of microbubbles, also known as ultrasound localization microscopy (ULM), many localization and tracking algorithms have been developed. ULM can image many centimeters into tissue in-vivo and track microvascular flow non-invasively with sub-diffraction resolution. In a significant community effort, we organized a challenge, Ultrasound Localization and TRacking Algorithms for Super-Resolution (ULTRA-SR). The aims of this paper are threefold: to describe the challenge organization, data generation, and winning algorithms; to present the metrics and methods for evaluating challenge entrants; and to report results and findings of the evaluation. Realistic ultrasound datasets containing microvascular flow for different clinical ultrasound frequencies were simulated, using vascular flow physics, acoustic field simulation and nonlinear bubble dynamics simulation. Based on these datasets, 38 submissions from 24 research groups were evaluated against ground truth using an evaluation framework with six metrics, three for localization and three for tracking. In-vivo mouse brain and human lymph node data were also provided, and performance assessed by an expert panel. Winning algorithms are described and discussed. The publicly available data with ground truth and the defined metrics for both localization and tracking present a valuable resource for researchers to benchmark algorithms and software, identify optimized methods/software for their data, and provide insight into the current limits of the field. In conclusion, Ultra-SR challenge has provided benchmarking data and tools as well as direct comparison and insights for a number of the state-of-the art localization and tracking algorithms.

2.
J Kidney Cancer VHL ; 11(1): 54-62, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567125

RESUMO

Small renal masses (SRMs) are often benign or early-stage cancers with low metastatic potential. The risk of overtreating SRMs is a particular concern in elderly or comorbid patients, for whom the risks associated with active surveillance (AS) are lower than the risks of surgical management. The aim is to systematically analyse a large cohort of AS patients to provide valuable insights into patient selection and outcomes concerning delayed intervention (DI) and AS termination. We retrospectively analysed data from 563 AS patients across three institutions from 2012 to 2023. Patients were classified into three groups: those currently in AS (n=283), those who underwent DI (n=75), and those who terminated AS (n=205). DI patients were younger, and had larger initial tumour size and higher growth rates (GRs) than AS patients. A significant number of patients terminated their AS, mainly due to comorbidities and death from non-kidney cancer causes, suggesting unsuitability for initial AS enrolment. AS appears to be a safe initial management strategy for SRMs, with an overall low GR and only one patient developing metastasis. The patient selection for AS appears inconsistent, highlighting the need for improved criteria to identify AS candidates, especially considering comorbidities and the possibility of subsequent active treatment in the event of progression.

4.
Int J Cancer ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602058

RESUMO

Treatment resistance remains a major issue in aggressive prostate cancer (PC), and novel genomic biomarkers may guide better treatment selection. Circulating tumor DNA (ctDNA) can provide minimally invasive information about tumor genomes, but the genomic landscape of aggressive PC based on whole-genome sequencing (WGS) of ctDNA remains incompletely characterized. Thus, we here performed WGS of tumor tissue (n = 31) or plasma ctDNA (n = 10) from a total of 41 aggressive PC patients, including 11 hormone-naïve, 15 hormone-sensitive, and 15 castration-resistant patients. Across all variant types, we found progressively more altered tumor genomic profiles in later stages of aggressive PC. The potential driver genes most frequently affected by single-nucleotide variants or insertions/deletions included the known PC-related genes TP53, CDK12, and PTEN and the novel genes COL13A1, KCNH3, and SENP3. Etiologically, aggressive PC was associated with age-related and DNA repair-related mutational signatures. Copy number variants most frequently affected 14q11.2 and 8p21.2, where no well-recognized PC-related genes are located, and also frequently affected regions near the known PC-related genes MYC, AR, TP53, PTEN, and BRCA1. Structural variants most frequently involved not only the known PC-related genes TMPRSS2 and ERG but also the less extensively studied gene in this context, PTPRD. Finally, clinically actionable variants were detected throughout all stages of aggressive PC and in both plasma and tissue samples, emphasizing the potential clinical applicability of WGS of minimally invasive plasma samples. Overall, our study highlights the feasibility of using liquid biopsies for comprehensive genomic characterization as an alternative to tissue biopsies in advanced/aggressive PC.

5.
Appetite ; 197: 107329, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561064

RESUMO

Consumption of sugar-sweetened beverages (SSB) is considered as an important risk factor for the development of overweight and obesity in populations worldwide, with a particular focus on the risks in the younger parts of the population - children and adolescents. Together with fiscal measures and information tools, innovation-based approaches such as the development of sugar-free or sugar-reduced versions of established beverages and development of new beverage products have been used to reduce this challenge, but the effects of product innovation on sugar intake are not well understood from the literature, as previous studies have largely ignored substitution effects of product innovation in the beverage domain. The objective of the present study was to investigate the potential effectiveness of product innovation as a strategy to affect consumers' intake of energy from sweetened non-alcoholic beverages. Using household panel shopping data from approximately 3000 Danish households over the years 2006-2014, we developed a hedonic pricing approach to estimate the influence of product attributes on consumers' utility, based on observed data for Danish households' purchases of sweet drinks. Overall, the study found that beverages' degree of sweetness positively affected the satiation effect of beverage consumption and in turn made the demand for these beverages less sensitive to e.g. price changes or introduction of competing products, whereas the energy density of the beverages positively affected the demand sensitivity to market changes. Findings like these can be useful for assessing market effects as well as environmental and public health impacts of changes to the market environment.


Assuntos
Comportamento do Consumidor , Bebidas Adoçadas com Açúcar , Criança , Adolescente , Humanos , Bebidas , Obesidade/etiologia , Obesidade/prevenção & controle , Sobrepeso , Comércio
6.
Nat Metab ; 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429390

RESUMO

Surviving long periods without food has shaped human evolution. In ancient and modern societies, prolonged fasting was/is practiced by billions of people globally for religious purposes, used to treat diseases such as epilepsy, and recently gained popularity as weight loss intervention, but we still have a very limited understanding of the systemic adaptions in humans to extreme caloric restriction of different durations. Here we show that a 7-day water-only fast leads to an average weight loss of 5.7 kg (±0.8 kg) among 12 volunteers (5 women, 7 men). We demonstrate nine distinct proteomic response profiles, with systemic changes evident only after 3 days of complete calorie restriction based on in-depth characterization of the temporal trajectories of ~3,000 plasma proteins measured before, daily during, and after fasting. The multi-organ response to complete caloric restriction shows distinct effects of fasting duration and weight loss and is remarkably conserved across volunteers with >1,000 significantly responding proteins. The fasting signature is strongly enriched for extracellular matrix proteins from various body sites, demonstrating profound non-metabolic adaptions, including extreme changes in the brain-specific extracellular matrix protein tenascin-R. Using proteogenomic approaches, we estimate the health consequences for 212 proteins that change during fasting across ~500 outcomes and identified putative beneficial (SWAP70 and rheumatoid arthritis or HYOU1 and heart disease), as well as adverse effects. Our results advance our understanding of prolonged fasting in humans beyond a merely energy-centric adaptions towards a systemic response that can inform targeted therapeutic modulation.

7.
Front Nutr ; 11: 1345922, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450230

RESUMO

Introduction: Carbohydrates and fats are the primary energy substrates during exercise, but proteins can also contribute. When proteins are degraded in the body, the amino groups are mainly converted to urea and excreted. Therefore, nitrogen excretion has been used as a marker of protein degradation, but a clear conclusion has yet to be reached on the effect of exercise on nitrogen excretion. Thus, we tested whether exercise increases nitrogen excretion. Methods: Fifteen young, healthy, moderate-to-well-trained participants (4 females, 11 males, VO2max 54.4 ± 1.7 mL·kg-1·min-1; mean ± SEM) participated in a randomized, balanced cross-over design investigation consisting of 1 day with 5 h of exercise (exercise day, EX) and 1 day with no exercise (control day, CON). The participants recorded their dietary intake the day before from 16:00 and throughout the intervention day. They then repeated these dietary intakes on the second trial day. A standardized lunch was provided on both days. In addition, participants were allowed to consume almost protein-free snacks in EX to ensure the same energy balance during both trial days. Urine was collected throughout the whole testing period, and urinary 3-methylhistidine (3-MH) excretion was measured to examine muscular catabolism. The sweat rate was calculated during the exercise period. Results and discussion: The urinary nitrogen and 3-MH excretions did not differ significantly between EX and CON (p = 0.764 and p = 0.953). The sweat rate was 2.55 ± 0.25 L in EX and 0.14 ± 0.15 L in CON (p < 0.001), and by estimating sweat nitrogen excretion, total nitrogen excretion was shown to differ with exercise. Our results showed that 5 hours of mixed exercise did not significantly impact urinary nitrogen and 3-MH excretions in healthy moderate-to-well-trained young adults.

8.
Nat Rev Microbiol ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509173

RESUMO

Sexually transmitted infections (STIs) have been part of human life since ancient times, and their symptoms affect quality of life, and sequelae are common. Socioeconomic and behavioural trends affect the prevalence of STIs, but the discovery of antimicrobials gave hope for treatment, control of the spread of infection and lower rates of sequelae. This has to some extent been achieved, but increasing antimicrobial resistance and increasing transmission in high-risk sexual networks threaten this progress. For Neisseria gonorrhoeae, the only remaining first-line treatment (with ceftriaxone) is at risk of becoming ineffective, and for Mycoplasma genitalium, for which fewer alternative antimicrobial classes are available, incurable infections have already been reported. For Chlamydia trachomatis, in vitro resistance to first-line tetracyclines and macrolides has never been confirmed despite decades of treatment of this highly prevalent STI. Similarly, Treponema pallidum, the cause of syphilis, has remained susceptible to first-line penicillin.

10.
Urology ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38458324

RESUMO

OBJECTIVE: To evaluate a cohort of patients diagnosed with benign ureteroenteric stricture (UES) after radical cystectomy with ileal conduits using a strict predefined definition of strictures. Additionally, we want to illustrate the UES debut, regarding symptoms and clinical findings. UES is a well-known long-term complication after radical cystectomy, affecting up to 20% of all patients. In the literature, different incidence rates are reported. However, these are based on various definitions of strictures. METHODS: We used strict predefined criteria to evaluate UES incidence including symptoms, timing, diagnostic methods, treatment, and outcome in all patients who underwent radical cystectomy with an ileal conduit between 2012 and 2018 at a single high-volume center. RESULTS: Of a total of 693 patients who underwent radical cystectomy with ileal conduit, we found 109 patients with 135 UES in total, corresponding to 15.7% of patients (CI: 13.2-18.6) and 10% of all included ureteroenteric anastomosis (CI: 8.5-11.6) after radical cystectomy. Median follow-up was 24months (interquartile range (IQR): 12-31), and postoperatively UES was diagnosed after a median of 6months (IQR: 3-16). A total of 56% was diagnosed with elevated creatinine. Every UES underwent a median of two (IQR: 1-2) treatment attempts and 122 UES were treated successfully. CONCLUSION: Benign UES is a significant cause of morbidity following radical cystectomy. Our findings contribute to the knowledge of timing, incidence, and recommended treatment of strictures. We argue the importance of establishing a clear gold standard when defining UES to ensure accurate reporting in future research.

11.
iScience ; 27(3): 109179, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439961

RESUMO

Urothelial carcinoma in situ (CIS) is an aggressive phenotype of non-muscle-invasive bladder cancer. Molecular features unique to CIS compared to high-grade papillary tumors are underexplored. RNA sequencing of CIS, papillary tumors, and normal urothelium showed lower immune marker expression in CIS compared to papillary tumors. We identified a 46-gene expression signature in CIS samples including selectively upregulated known druggable targets MTOR, TYK2, AXIN1, CPT1B, GAK, and PIEZO1 and selectively downregulated BRD2 and NDUFB2. High expression of selected genes was significantly associated with CIS in an independent dataset. Mutation analysis of matched CIS and papillary tumors revealed shared mutations between samples across time points and mutational heterogeneity. CCDC138 was the most frequently mutated gene in CIS. The immunological landscape showed higher levels of PD-1-positive cells in CIS lesions compared to papillary tumors. We identified CIS lesions to have distinct characteristics compared to papillary tumors potentially contributing to the aggressive phenotype.

12.
Nutrients ; 16(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38337697

RESUMO

The main purpose of this study was to investigate the effect of a novel alginate-encapsulated carbohydrate-protein (CHO-PRO ratio 2:1) supplement (ALG) on cycling performance. The ALG, designed to control the release of nutrients, was compared to an isocaloric carbohydrate-only control (CON). Alginate encapsulation of CHOs has the potential to reduce the risk of carious lesions. METHODS: In a randomised cross-over clinical trial, 14 men completed a preliminary test over 2 experimental days separated by ~6 days. An experimental day consisted of an exercise bout (EX1) of cycling until exhaustion at W~73%, followed by 5 h of recovery and a subsequent time-to-exhaustion (TTE) performance test at W~65%. Subjects ingested either ALG (0.8 g CHO/kg/hr + 0.4 g PRO/kg/hr) or CON (1.2 g CHO/kg/hr) during the first 2 h of recovery. RESULTS: Participants cycled on average 75.2 ± 5.9 min during EX1. Levels of plasma branched-chain amino acids decreased significantly after EX1, and increased significantly with the intake of ALG during the recovery period. During recovery, a significantly higher plasma insulin and glucose response was observed after intake of CON compared to ALG. Intake of ALG increased plasma glucagon, free fatty acids, and glycerol significantly. No differences were found in the TTE between the supplements (p = 0.13) nor in the pH of the subjects' saliva. CONCLUSIONS: During the ALG supplement, plasma amino acids remained elevated during the recovery. Despite the 1/3 less CHO intake with ALG compared to CON, the TTE performance was similar after intake of either supplement.


Assuntos
Alginatos , Desempenho Atlético , Masculino , Humanos , Alginatos/farmacologia , Desempenho Atlético/fisiologia , Resistência Física , Carboidratos da Dieta/farmacologia , Atletas , Suplementos Nutricionais
13.
NPJ Precis Oncol ; 8(1): 48, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395986

RESUMO

Current prognostic tools cannot clearly distinguish indolent and aggressive prostate cancer (PC). We hypothesized that analyzing individual contributions of epithelial and stromal components in localized PC (LPC) could improve risk stratification, as stromal subtypes may have been overlooked due to the emphasis on malignant epithelial cells. Hence, we derived molecular subtypes of PC using gene expression analysis of LPC samples from prostatectomy patients (cohort 1, n = 127) and validated these subtypes in two independent prostatectomy cohorts (cohort 2, n = 406, cohort 3, n = 126). Stroma and epithelium-specific signatures were established from laser-capture microdissection data and non-negative matrix factorization was used to identify subtypes based on these signatures. Subtypes were functionally characterized by gene set and cell type enrichment analyses, and survival analysis was conducted. Three epithelial (E1-E3) and three stromal (S1-S3) PC subtypes were identified. While subtyping based on epithelial signatures showed inconsistent associations to biochemical recurrence (BCR), subtyping by stromal signatures was significantly associated with BCR in all three cohorts, with subtype S3 indicating high BCR risk. Subtype S3 exhibited distinct features, including significantly decreased cell-polarity and myogenesis, significantly increased infiltration of M2-polarized macrophages and CD8 + T-cells compared to subtype S1. For patients clinically classified as CAPRA-S intermediate risk, S3 improved prediction of BCR. This study demonstrates the potential of stromal signatures in identification of clinically relevant PC subtypes, and further indicated that stromal characterization may enhance risk stratification in LPC and may be particularly promising in cases with high prognostic ambiguity based on clinical parameters.

14.
Eur Urol Open Sci ; 60: 8-14, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38375343

RESUMO

Background: Approximately 15% of patients undergoing radical cystectomy (RC) develop benign ureteroenteric strictures. Of these strictures, the majority are located in the left ureter. To lower the rate of strictures, a retrosigmoid ileal conduit has been suggested. Objective: To investigate the feasibility and safety of a retrosigmoid ileal conduit during robot-assisted RC in bladder cancer patients. Design setting and participants: This randomized controlled trial included 303 patients from all five cystectomy centers in Denmark from May 2020 to August 2022. Participants were diagnosed with bladder cancer and scheduled for robot-assisted RC with an ileal conduit. Intervention: Intervention group: a retrosigmoid ileal conduit was constructed using approximately 25 cm of the terminal ileum and tunneled behind the sigmoid where the left ureter was anastomosed from end to side. Control group: the conventional ileal conduit ad modum Bricker with individual end-to-side anastomoses. Outcome measurements and statistical analysis: Patients were analyzed by the intention-to-treat approach. Complications within 90 d were categorized using the Clavien-Dindo grading system and compared using Fisher's exact test. Wilcoxon's test was used for pre- and postoperative renal function. Results and limitations: Of the 149 patients randomized for the retrosigmoid ileal conduit (MOSAIC), a total of 137 (92%) patients received the allocated conduit. Postoperative complications were distributed equally between the two groups. The relative risk of Clavien-Dindo complications of grade ≥III was 1.12 (95% confidence interval: 0.96-1.31) in the intervention group compared with the control group. Conclusions: The retrosigmoid ileal conduit with robot-assisted RC was technically feasible. Early postoperative complications were not significantly different when comparing the two groups. Further investigation of long-term complications, including strictures, is needed. Patient summary: We compared a conventional urinary diversion with a longer conduit to prevent constriction from developing in the ureters. The new conduit is feasible and safe within the first 90 d, with no differences in postoperative complications from those of the conventional diversion.

15.
Scand J Urol ; 59: 39-46, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38406925

RESUMO

OBJECTIVE: To investigate the impact of neoadjuvant chemotherapy implementation with gemcitabine-cisplatin on survival outcomes for patients with muscle-invasive bladder cancer in Denmark. MATERIALS AND METHODS: Data were collected on all patients in Denmark undergoing radical cystectomy who were potential candidates for neoadjuvant chemotherapy from 2010 to 2015 (n = 851). A cohort before the implementation of neoadjuvant chemotherapy (Cohort 2010-12) was compared with a cohort after implementation (Cohort 2013-15). Patients in Cohort 2013-15 receiving neoadjuvant chemotherapy (+NAC, n = 213) were compared with patients in Cohort 2013-15 not receiving neoadjuvant chemotherapy (-NAC, n = 139). Pathological results after radical cystectomy and oncological outcomes were compared between the study cohorts. Overall survival, disease-free survival, and disease-specific survival were compared with Kaplan-Meier plots and with univariable and multivariable Cox regression. Kaplan-Meier estimates of overall survival were also performed separately for treating hospital and for pathological stage. RESULTS: Pathological T0 (pT0) was more frequent in patients who received neoadjuvant chemotherapy: 34% versus 18% when comparing Cohort 2013-15 with Cohort 2010-12 (p < 0.001), and 46% versus 16% in +NAC compared with -NAC (p < 0.001). Overall survival, disease-free survival, and disease-specific survival at 5 years after cystectomy were not improved in Cohort 2013-15 compared with Cohort 2010-12 with adjusted hazard ratios of 1.11 (95% confidence interval [CI]: 0.87-1.43), 1.02 (95% CI: 0.81-1.29), and 1.06 (95% CI: 0.80-1.41), respectively. CONCLUSIONS: This observational study found no improved survival in a national cohort of patients with muscle-invasive bladder cancer undergoing radical cystectomy after implementation of NAC. However, reservations should be made regarding the study design and the true effect of NAC on survival outcomes.


Assuntos
Terapia Neoadjuvante , Neoplasias da Bexiga Urinária , Humanos , Cistectomia/métodos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/cirurgia , Dinamarca , Músculos/patologia , Estudos Retrospectivos , Quimioterapia Adjuvante , Invasividade Neoplásica
16.
Urol Oncol ; 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38403529

RESUMO

A plethora of urine markers for the management of patients with bladder cancer has been developed and studied in the past. However, the clinical impact of urine testing on patient management remains obscure. The goal of this manuscript is to identify scenarios for the potential use of molecular urine markers in the follow-up of patients with high-risk non-muscle-invasive BC (NMIBC) and estimate potential risks and benefits. Information on the course of disease of patients with high-risk NMIBC and performance data of a point-of-care test (UBC rapid™), an MCM-5 directed ELISA (ADXBLADDER™), and 2 additional novel assays targeting alterations of mRNA expression and DNA methylation (Xpert bladder cancer monitor™, Epicheck™) were retrieved from high-quality trials and/or meta-analyses. In addition, the sensitivity of white light cystoscopy (WLC) and the impact of a urine marker result on the performance of WLC were estimated based on fluorescence cystoscopy data and information from the CeFub trial. This information was applied to different scenarios in patient follow-up and sensitivity, estimated number of cystoscopies, and the numbers needed to diagnose were calculated. The sensitivity of guideline-based regular follow-up (SOC) at 1 year was calculated at 96%. For different marker-supported strategies sensitivities ranging from 77% to 97.9% were estimated. Calculations suggest that several strategies are effective for the SOC. While for the SOC 24.6 WLCs were required to diagnose 1 tumor recurrence (NND), this NND dropped below 5 in some marker-supported strategies. Based on the results of this simulation, a marker-supported follow-up of patients with HR NMIBC is safe and offers the option to significantly reduce the number of WLCs. Further research focusing on prospective randomized trials is needed to finally find a way to implement urine markers into clinical decision-making.

17.
J Robot Surg ; 18(1): 31, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38231282

RESUMO

The objective of this study was to evaluate the effect of low pneumoperitoneum pressure (Pnp) on renal function and renal injury biomarkers during robot-assisted radical prostatectomy (RARP). A single-centre, triple-blinded, randomised clinical trial was conducted with 98 patients undergoing RARP, who were assigned to either standard Pnp of 12 mmHg or low Pnp of 7 mmHg. The primary outcome was urinary neutrophil gelatinase-associated lipocalin (u-NGAL), and several other kidney injury biomarkers were assessed as secondary outcomes. Acute kidney injury (AKI) was evaluated using the Kidney Disease Improving Global Outcomes (KDIGO) criteria, the gold standard method for defining AKI. The trial was registered on ClinicalTrials.gov (NCT04755452). Patients in the low Pnp group had significantly lower levels of u-NGAL (mean difference - 39.9, 95% CI - 73.7 to - 6.1, p = 0.02) compared to the standard Pnp group. No significant differences were observed for other urinary biomarkers. Interestingly, there was a significant difference in intraoperative urine production between the groups (low Pnp median: 200 mL, IQR: 100-325 vs. standard Pnp median: 100 mL, IQR: 50-200, p = 0.01). Similarly, total postoperative urine production also varied significantly (low Pnp median: 1325 mL, IQR: 1025-1800 vs. standard Pnp median: 1000 mL, IQR: 850-1287, p = 0.001). The occurrence of AKI, as defined by the KDIGO criteria, did not differ significantly between the groups. Low Pnp during RARP resulted in lower u-NGAL levels, suggesting a potential benefit in terms of reduced renal injury. However, the lack of a notable difference in AKI as defined by the KDIGO criteria indicates that the clinical significance of this finding may be limited. Further research is needed to validate and expand on these results, ultimately defining the optimal Pnp strategy for RARP and improving patient outcomes.


Assuntos
Injúria Renal Aguda , Pneumoperitônio , Procedimentos Cirúrgicos Robóticos , Robótica , Masculino , Humanos , Lipocalina-2 , Pneumoperitônio/etiologia , Procedimentos Cirúrgicos Robóticos/métodos , Prostatectomia/efeitos adversos , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Rim/cirurgia , Biomarcadores
18.
Sci Rep ; 14(1): 1864, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253772

RESUMO

The left atrium (LA) hemodynamic indices hold prognostic value in various cardiac diseases and disorders. To understand the mechanisms of these conditions and to assess the performance of cardiac devices and interventions, in vitro models can be used to replicate the complex physiological interplay between the pulmonary veins, LA, and left ventricle. In this study, a comprehensive and adaptable in vitro model was created. The model includes a flexible LA made from silicone and allows distinct control over the systolic and diastolic functions of both the LA and left ventricle. The LA was mechanically matched with porcine LAs through expansion tests. Fluid dynamic measures were validated against the literature and pulmonary venous flows recorded on five healthy individuals using magnetic resonance flow imaging. Furthermore, the fluid dynamic measures were also used to construct LA pressure-volume loops. The in vitro pressure and flow recordings expressed a high resemblance to physiological waveforms. By decreasing the compliance of the LA, the model behaved realistically, elevating the a- and v-wave peaks of the LA pressure from 12 to 19 mmHg and 22 to 26 mmHg, respectively, while reducing the S/D ratio of the pulmonary venous flowrate from 1.5 to 0.3. This model provides a realistic platform and framework for developing and evaluating left heart procedures and interventions.


Assuntos
Apêndice Atrial , Cardiopatias , Humanos , Animais , Suínos , Hidrodinâmica , Átrios do Coração/diagnóstico por imagem , Ventrículos do Coração
19.
Ann Anat ; 252: 152195, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38042354

RESUMO

BACKGROUND: In 2008, members of the TEPARG provided first insights into the legal and ethical framework governing body donation in Europe. In 2012, a first update followed. This paper is now the second update on this topic and tries to extend the available information to many more European countries. METHODS: For this second update, we have asked authors from all European countries to contribute their national perspectives. By this enquiry, we got many contributions compiled in this paper. When we did not get a personal contribution, one of us (EB) searched the internet for relevant information. RESULTS: Perspectives on the legal and ethical framework governing body donation in Europe. CONCLUSIONS: We still see that a clear and rigorous legal framework is still unavailable in several countries. We found national regulations in 18 out of 39 countries; two others have at least federal laws. Several countries accept not only donated bodies but also utilise unclaimed bodies. These findings can guide policymakers in reviewing and updating existing laws and regulations related to body donation and anatomical studies.


Assuntos
Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Humanos , Cadáver , Europa (Continente) , Corpo Humano
20.
Artigo em Inglês | MEDLINE | ID: mdl-37878425

RESUMO

Spherical diverging acoustic lenses mounted on flat 2-D row-column-addressed (RCA) ultrasound transducers have shown the potential to extend the field of view (FOV) from a rectilinear to a curvilinear volume region and, thereby, enable 3-D imaging of large organs. Such lenses are usually designed for small aperture low-frequency transducers, which have limited resolution. Moreover, they are made of off-the-shelf pieces of materials, which leaves no room for optimization. We hypothesize that acoustic lenses can be designed to fit high-resolution transducers, and they can be fabricated in a fast, cost-effective, and flexible manner using a combination of 3-D printing and casting or computer numerical control (CNC) machining techniques. These lenses should increase the FOV of the array while preserving the image quality. In this work, such lenses are made in concave, convex, and compound spherical shapes and from thermoplastics and thermosetting polymers. Polymethylpentene (TPX), polystyrene (PS), polypropylene (PP), polymethyl methacrylate (PMMA), polydimethylsiloxane (PDMS), and room-temperature-vulcanizing (RTV) silicone diverging lenses have been fabricated and mounted on a 128 + 128 6-MHz RCA transducer. The performances of the lenses have been assessed and compared in terms of FOV, signal-to-noise ratio (SNR), bandwidth, and potential artifacts. The largest FOV (24.0.) is obtained with a 42.64-mm radius PMMA-RTV compound lens, which maintains a decent fractional bandwidth (53%) and SNR at 6 MHz (.9.1-dB amplitude drop compared with the unlensed transducer). The simple PMMA TPX, PS, PP, PDMS, and RTV lenses provide an FOV of 12.2°, 6.3°, 8.1°, 11.7°, 0.6°, and 10.4°; a fractional bandwidth of 97%, 46%, 103%, 46%, 97%, 53%, and 49%; and an amplitude drop of -5.2, -4.4, -2.8, -15.4, -6.0, and -1.8 dB, respectively. This work demonstrates that thermoplastics are suitable materials for fabricating low-attenuation convex diverging lenses for large-aperture, high-frequency 2-D transducers. This is highly desired to achieve high-resolution volumetric imaging of large organs.

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