RESUMO
To examine the association between blood urea nitrogen (BUN) and risk of type 2 diabetes (T2DM) among Chinese adults, we performed an ongoing cohort study of 38578 Chinese adults (56.3% males; average age, 41.6 y) who underwent repeated health check-up examinations between 2009 and 2016 and without T2DM at baseline. During follow-up, incident T2DM cases were identified based on self-report, medication use, measurements of fasting plasma glucose, 2 h post oral glucose, or haemoglobinA1c. 2009 (5.2%) cases confirmed with incident T2DM were identified during median follow-up of 3.1 years. With increasing quartiles of BUN levels, the incidences of T2DM gradually increased with 0.69%, 1.11%, 1.53%, and 1.87% for quartile 1 to quartile 4 (p trend <0.001). Compared with quartile 1, the multivariate-adjusted hazard ratios (HRs) and its 95% confidence intervals (95% CIs) for T2DM risk were 1.16 (0.97-1.38) for quartile 2, 1.28 (1.07-1.51) for quartile 3, and 1.28 (1.08-1.52) for quartile 4 (p trend = 0.005). HR for per each standard deviation increase in BUN level was 1.10 (1.04-1.16) (p trend <0.001). This association tended to be more pronounced in those with a lower body mass index at baseline (p-interaction <0.001). Our results suggested that BUN levels were positively associated with incident T2DM risk among Chinese adults. Future prospective investigations in other populations are necessary to confirm our findings.
Assuntos
Nitrogênio da Ureia Sanguínea , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Adulto , Idoso , Povo Asiático/estatística & dados numéricos , Glicemia/análise , Índice de Massa Corporal , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
BACKGROUND: Training for ultrasound-guided central venous catheterization (CVC) is typically conducted on static manikin simulators with real-time feedback from a skilled observer. Dynamic haptic robotic trainers (DHRTs) are an alternative method that simulates various patient anatomies and provides consistent feedback for each insertion. This study evaluates CVC needle insertion efficiency and skill gains of both methods. MATERIALS AND METHODS: Fifty-two first-year surgical residents were trained by placing internal jugular (IJ) CVC needles in manikins (n = 26) or robots (n = 26). Manikin-trained participants received verbal feedback from an experienced observer, whereas robotically trained participants received quantitative feedback from the personalized DHRT learning interface. All participants were pretested on a Blue Phantom manikin; participants completed posttesting on a Blue Phantom manikin (n = 26) or a novel manikin (n = 26) with different vessel depth and position. During pretests and posttests residents were timed, motion-tracked, and scored on an IJ CVC checklist. RESULTS: (1) All skills on the IJ CVC checklist showed significant (P < 0.014) improvements from pretests to posttest; (2) Average angle of insertion, path length, and jerk improved significantly (P < 0.005); (3) Average procedural completion time, with standard error (SE) reported, decreased significantly from pretest (M = 3.516 min, SE = 0.277) to posttest (M = 1.997, SE = 0.409). CONCLUSIONS: No significant group differences were observed in overall skill gains, but residents' average procedural completion time decreased significantly from pretests to posttest. Overall results support DHRT as an effective method for training IJ CVC skills.
Assuntos
Cateterismo Venoso Central/métodos , Educação de Pós-Graduação em Medicina/métodos , Treinamento por Simulação/métodos , Cateterismo Venoso Central/instrumentação , Competência Clínica/estatística & dados numéricos , Avaliação Educacional/métodos , Avaliação Educacional/estatística & dados numéricos , Feminino , Cirurgia Geral/educação , Humanos , Internato e Residência , Masculino , Manequins , Agulhas , Robótica , Fatores de Tempo , Ultrassonografia de IntervençãoRESUMO
Iron pyrite (FeS2) is considered a promising earth-abundant semiconductor for solar energy conversion with the potential to achieve terawatt-scale deployment. However, despite extensive efforts and progress, the solar conversion efficiency of iron pyrite remains below 3%, primarily due to a low open circuit voltage (VOC). Here we report a comprehensive investigation on {100}-faceted n-type iron pyrite single crystals to understand its puzzling low VOC. We utilized electrical transport, optical spectroscopy, surface photovoltage, photoelectrochemical measurements in aqueous and acetonitrile electrolytes, UV and X-ray photoelectron spectroscopy, and Kelvin force microscopy to characterize the bulk and surface defect states and their influence on the semiconducting properties and solar conversion efficiency of iron pyrite single crystals. These insights were used to develop a circuit model analysis for the electrochemical impedance spectroscopy that allowed a complete characterization of the bulk and surface defect states and the construction of a detailed energy band diagram for iron pyrite crystals. A holistic evaluation revealed that the high-density of intrinsic surface states cannot satisfactorily explain the low photovoltage; instead, the ionization of high-density bulk deep donor states, likely resulting from bulk sulfur vacancies, creates a nonconstant charge distribution and a very narrow surface space charge region that limits the total barrier height, thus satisfactorily explaining the limited photovoltage and poor photoconversion efficiency of iron pyrite single crystals. These findings lead to suggestions to improve single crystal pyrite and nanocrystalline or polycrystalline pyrite films for successful solar applications.
RESUMO
BACKGROUND: The association of BCAAs (isoleucine, leucine, and valine) with cardiovascular and cerebrovascular diseases has been widely recognized by researchers, but there is limited evidence to support the relationship between BCAAs and multiple chronic conditions (MCCs) in older adults. This study aimed to explore the correlation between BCAA levels in the diets of older adults and MCCs. METHODS: Based on a health management cohort project in Nanshan District of Shenzhen, 4278 individuals over 65 years old were selected as participants via multi-stage stratified sampling from May 2018 to December 2019. Data were collected using a validated semi-quantitative food frequency questionnaire, as well as anthropometric and chronic disease reports. MCC was defined as the coexistence of two or more chronic diseases, namely, hypertension, dyslipidemia, diabetes, CAD, stroke, CKD, and CLD. Multivariate unconditional logistic regression analysis was used to analyze the relationship between dietary BCAAs and MCCs in older adults, and then, gender stratification analysis was performed. A restricted cubic spline model (a fitted smooth curve) was used to determine the dose-response relationship of isoleucine with MCCs. RESULTS: A total of 4278 older adults aged 65 and above were included in this study, with an average age of 72.73 ± 5.49 years. The cohort included 1861 males (43.50%). Regardless of whether confounding factors were corrected, isoleucine was a risk factor for MCCs (OR = 3.388, 95%CI:1.415,8.109). After gender stratification, the relationships between dietary isoleucine and MCCs (OR = 6.902, 95%CI:1.875,25.402) and between leucine (OR = 0.506,95%CI:0.309,0.830) and MCCs were significant in women, but not in men. No significant association between valine and MCCs was observed. In addition, isoleucine was a risk factor for MCCs when its intake was greater than 4.297 g/d. CONCLUSION: Isoleucine may play an important role in regulating age-related diseases. BCAAs such as isoleucine can be used as risk markers for MCCs in older adults.
RESUMO
The present study investigated the association between the presence of periodontitis and aortic calcification (AC) risk among Chinese adults. A total of 6059 individuals who underwent regular health check-ups and received a diagnosis of periodontitis between 2009 and 2016 were included. The outcome was AC, assessed by a chest low-dose spiral CT scan. Cox proportional hazards regression analysis was used to assess the association between periodontitis and AC risk after adjusting for several confounders. After a median follow-up period of 2.3 years (interquartile range: 1.03-4.97 years), 843 cases of AC were identified, with 532 (12.13%) and 311 (18.59%) patients in the non-periodontitis group and periodontitis group, respectively. Multivariate analyses demonstrated that, compared with those without periodontitis, the hazard ratio and 95% confidence interval for AC risk in participants with periodontitis was 1.18 (1.02-1.36) (P = .025) in the fully adjusted model. Stratified analyses showed that the positive relationship between periodontitis and AC was more evident in males and participants <65 years of age (pinteraction = .005 and .004, respectively). Our results show that the presence of periodontitis was positively associated with AC among Chinese adults, especially among males and younger participants.
Assuntos
Calcinose , Calcificação Vascular , Humanos , Estudos de Coortes , Periodontite , China , Radiografia Torácica , Aorta Torácica/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Calcinose/etiologiaRESUMO
AIMS/INTRODUCTION: The current literature suggests that men with diabetes have a lower prostate-specific antigen concentration than men without diabetes, but the causal association remains unclear. We aimed to investigate the association between serum prostate-specific antigen concentrations and the risk of type 2 diabetes mellitus in a cohort study of a Chinese population. MATERIALS AND METHODS: We designed a cohort study that comprised 16,811 initially non-diabetic Chinese men who received annual health checkups between 2009 and 2016. The outcome of this study was type 2 diabetes mellitus, identified by medical diagnosis, self-reportage, medication use, fasting glucose, 2-h post oral glucose or glycated hemoglobin measurements. Cox proportional hazards models were carried out to evaluate the association. RESULTS: During a median follow-up period of 3.8 years (interquartile range 1.91-5.73 years), 1,260 participants developed incident type 2 diabetes mellitus. The multivariable model, adjusted for various potential confounders, showed that serum prostate-specific antigen concentrations were inversely related to type 2 diabetes mellitus risk (P for trend = 0.014). Compared with the lowest quartile of serum prostate-specific antigen, the hazard ratio and 95% confidence intervals of type 2 diabetes mellitus risk for quartile 2-4 were 0.84 (0.66-1.07), 0.75 (0.59-0.94) and 0.77 (0.62-0.96), respectively. Subgroup analyses suggested the inverse relationship was more prominent in overweight or obese participants (P for interaction = 0.013). CONCLUSIONS: High serum prostate-specific antigen concentration was associated with a low risk of type 2 diabetes mellitus in Chinese men. Future studies are required to confirm these findings and investigate underlying mechanisms.
Assuntos
Biomarcadores/sangue , Glicemia/análise , Diabetes Mellitus Tipo 2/epidemiologia , Antígeno Prostático Específico/sangue , Adulto , Idoso , China/epidemiologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/patologia , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de RiscoRESUMO
BACKGROUND: The objective of this study was to validate the transfer of ultrasound-guided Internal Jugular Central Venous Catheterization (US-IJCVC) placement skills from training on a Dynamic Haptic Robotic Trainer (DHRT), to placing US-IJCVCs in clinical environments. DHRT training greatly reduces preceptor time by providing automated feedback, standardizes learning experiences, and quantifies skill improvements. METHODS: Expert observers evaluated DHRT-trained (Nâ¯=â¯21) and manikin-trained (Nâ¯=â¯36) surgical residents on US-IJCVC placement in the operating suite using a US-IJCVC evaluation form. Performance and errors by DHRT-trained residents were compared to traditional manikin-trained residents. RESULTS: There were no significant training group differences between unsuccessful insertions (pâ¯=â¯0.404), assistance on procedure (pâ¯=â¯0.102), arterial puncture (pâ¯=â¯0.998), and average number of insertion attempts (pâ¯=â¯0.878). Regardless of training group, previous central line experience significantly predicted whether residents needed assistance on the procedure (pâ¯=â¯0.033). CONCLUSION: The results failed to show a statistical difference between DHRT- and manikin-trained residents. This study validates the transfer of skills from training on the DHRT system to performing US-IJCVC in clinical environments.
Assuntos
Cateterismo Venoso Central/métodos , Competência Clínica , Educação de Pós-Graduação em Medicina/organização & administração , Cirurgia Geral/educação , Procedimentos Cirúrgicos Robóticos/educação , Treinamento por Simulação/métodos , Centros Médicos Acadêmicos , Feminino , Humanos , Internato e Residência/organização & administração , Veias Jugulares , Modelos Logísticos , Masculino , Manequins , Pennsylvania , Ultrassonografia de Intervenção/métodosRESUMO
INTRODUCTION: Brachial-ankle pulse wave velocity (ba-PWV), as a simple and easily measured marker of arterial stiffness, has not been prospectively explored for its role in type 2 diabetes mellitus (T2DM) risk among the general population. This study aimed to explore the association between baseline ba-PWV value and new-onset T2DM among Chinese adults. RESEARCH DESIGN AND METHODS: Using data from Xiaotangshan Hospital, we conducted a prospective cohort study among those who underwent annual or biennial health check-up examinations and who had their ba-PWV measured from 2009 to 2016. We explored the risk of new-onset T2DM across ba-PWV tertiles using Cox proportional-hazards regression analysis. RESULTS: Of 6122 adults (68.9% male; mean age: 51.0 (SD 13.0) years) without T2DM and with ba-PWV measured at baseline, 599 participants developed T2DM during an average of 3.8 (SD 2.3) years of follow-up. After multivariable adjustment, ba-PWV was positively related to T2DM risk (p for trend=0.008). Compared with the lowest ba-PWV tertile, the HRs and their 95% CIs were 1.57 (1.18 to 2.10) for the second and 1.66 (1.24 to 2.22) for the third tertile. The risk across ba-PWV tertiles increased steadily from 1000 cm/s to 1400 cm/s and then reached a plateau. Subgroup analyses indicated a significantly higher risk among those aged <65 years and current smokers (p for interactions: <0.001 and 0.006). CONCLUSIONS: Our findings suggest that ba-PWV might be a useful and independent predictor of new-onset T2DM with ba-PWV ranging between 1000 cm/s and 1400 cm/s, especially among younger individuals and current smokers.
Assuntos
Índice Tornozelo-Braço , Diabetes Mellitus Tipo 2 , Adulto , Estudos de Coortes , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Onda de Pulso , Fatores de RiscoRESUMO
Medical simulation training is widely used to effectively train for invasive medical procedures such as peripheral nerve blocks. Traditionally, accurate haptic training relies on expensive cadavers, manikins, or advanced haptic robots. Proposed herein is a novel concept for haptic training called the low-cost haptic force needle insertion simulator (LCNIS), which uses material fracture inside disposable cartridges to accurately replicate the force of inserting a needle into tissue. Cadaver and material fracture experiments were performed to develop and determine the accuracy of the LCNIS. The material testing showed that polycarbonate had the highest maximum needle puncture force of the materials tested, 9.85 N, and that fluorinated ethylene propylene had the lowest maximum puncture force, 0.84 N. The cadaver results showed that the error between the three peak forces in a cadaver and a cadaver mimicking cartridge was 1.00 N, 0.01 N, and 1.54 N. The standard deviation of these peaks was 0.60 N, 0.55 N, and 0.41 N. This novel method of haptic simulation can easily be adapted to recreate any type of force and, therefore, could be utilized to train for a wide variety of medical procedures.
Assuntos
Competência Clínica , Educação Médica/métodos , Treinamento por Simulação , Humanos , AgulhasRESUMO
BACKGROUND: The objective of this study was to determine whether gaze patterns could differentiate expertise during simulated ultrasound-guided Internal Jugular Central Venous Catheterization (US-IJCVC) and if expert gazes were different between simulators of varying functional and structural fidelity. METHODS: A 2017 study compared eye gaze patterns of expert surgeons (nâ¯=â¯11), senior residents (nâ¯=â¯4), and novices (nâ¯=â¯7) during CVC needle insertions using the dynamic haptic robotic trainer (DHRT), a system which simulates US-IJCVC. Expert gaze patterns were also compared between a manikin and the DHRT. RESULTS: Expert gaze patterns were consistent between the manikin and DHRT environments (pâ¯=â¯0.401). On the DHRT system, CVC experience significantly impacted the percent of time participants spent gazing at the ultrasound screen (pâ¯<â¯0.0005) and the needle and ultrasound probe (pâ¯<â¯0.0005). CONCLUSION: Gaze patterns differentiate expertise during ultrasound-guided IJCVC placement and the fidelity of the simulator does not impact gaze patterns.
Assuntos
Cateterismo Venoso Central , Competência Clínica , Educação de Pós-Graduação em Medicina/métodos , Internato e Residência/métodos , Manequins , Robótica/educação , Ultrassonografia de Intervenção , HumanosRESUMO
INTRODUCTION: High-tech simulators are gaining popularity in surgical training programs because of their potential for improving clinical outcomes. However, most simulators are static in nature and only represent a single anatomical patient configuration. The Dynamic Haptic Robotic Training (DHRT) system was developed to simulate these diverse patient anatomies during Central Venous Catheterization (CVC) training. This article explores the use of the DHRT system to evaluate objective metrics for CVC insertion by comparing the performance of experts and novices. METHODS: Eleven expert surgeons and 13 first-year surgical residents (novices) performed multiple needle insertion trials on the DHRT system. Differences between expert and novice performance on the following five metrics were assessed using a multivariate analysis of variance: path length, standard deviation of deviations (SDoD), average velocity, distance to the center of the vessel, and time to complete (TtC) the needle insertion. A regression analysis was performed to identify if expertise could be predicted using these metrics. Then, a curve fit was conducted to identify whether learning curves were present for experts or novices on any of these five metrics. RESULTS: Time to complete the insertion and SDoD of the needle tip from an ideal path were significantly different between experts and novices. Learning curves were not present for experts but indicated a significant decrease in path length and TtC for novices. CONCLUSIONS: The DHRT system was able to identify significant differences in TtC and SDoD between experts and novices during CVC needle insertion procedures. In addition, novices were shown to improve their skills through DHRT training.
Assuntos
Cateterismo Venoso Central/métodos , Simulação por Computador , Modelos Anatômicos , Cateterismo Venoso Central/normas , Competência Clínica , Humanos , Internato e Residência , Análise de Regressão , Fatores de TempoRESUMO
Manikins have traditionally been used to train ultrasound-guided Central Venous Catheterization (CVC), but are static in nature and require an expert observer to provide feedback. As a result, virtual simulation and personalized learning has been increasingly adopted in medical education to efficiently provide quantitative feedback. The Dynamic Haptic Robotic Trainer (DHRT) trains surgical residents in CVC needle insertions by simulating various patient profiles and presenting personalized feedback on objective performance. However, no studies have examined the learning gains of the personalized learning feedback or the relation of feedback to what the user is focusing on during the training. Thus, this study was developed to determine the effectiveness of the current personalized learning interface through a long-term investigation with 7 surgical residents. The eye tracking analysis showed that residents spent significantly more time fixated on percent aspiration throughout the study; the more time participants spent looking at the Number of Insertions, Percent Aspiration and the Angle of Insertion on the DHRT GUI, the better they performed on subsequent trials on the DHRT system.
RESUMO
OBJECTIVE: To compare the effect of simulator functional fidelity (manikin vs a Dynamic Haptic Robotic Trainer [DHRT]) and personalized feedback on surgical resident self-efficacy and self-ratings of performance during ultrasound-guided internal jugular central venous catheterization (IJ CVC) training. In addition, we seek to explore how self-ratings of performance compare to objective performance scores generated by the DHRT system. DESIGN: Participants were randomly assigned to either manikin or DHRT IJ CVC training over a 6-month period. Self-efficacy surveys were distributed before and following training. Training consisted of a pretest, 22 practice IJ CVC needle insertion attempts, 2 full-line practice attempts, and a posttest. Participants provided self-ratings of performance for each needle insertion and were presented with feedback from either an upper level resident (manikin) or a personalized learning system (DHRT). SETTING: A study was conducted from July 2016 to February 2017 through a surgical skills training program at Hershey Medical Center in Hershey, Pennsylvania. PARTICIPANTS: Twenty-six first-year surgical residents were recruited for the study. Individuals were informed that IJ CVC training procedures would be consistent regardless of participation in the study and that participation was optional. All recruited residents opted to participate in the study. RESULTS: Residents in both groups significantly improved their self-efficacy scores from pretest to posttest (p < 0.01). Residents in the manikin group consistently provided higher self-ratings of performance (p < 0.001). Residents in the DHRT group recorded more feedback on errors (228 instances) than the manikin group (144 instances). Self-ratings of performance on the DHRT system were able to significantly predict the objective score of the DHRT system (R2 = 0.223, p < 0.001). CONCLUSION: Simulation training with the DHRT system and the personalized learning feedback can improve resident self-efficacy with IJ CVC procedures and provide sufficient feedback to allow residents to accurately assess their own performance.
Assuntos
Cateterismo Venoso Central , Competência Clínica , Educação de Pós-Graduação em Medicina/métodos , Cirurgia Geral/educação , Manequins , Robótica , Retroalimentação , Feminino , Humanos , Internato e Residência/métodos , Masculino , Autoeficácia , Treinamento por Simulação/métodosRESUMO
Many solid tumors contain an overabundance of phospholipid ethers relative to normal cells. Capitalizing on this difference, we created cancer-targeted alkylphosphocholine (APC) analogs through structure-activity analyses. Depending on the iodine isotope used, radioiodinated APC analog CLR1404 was used as either a positron emission tomography (PET) imaging ((124)I) or molecular radiotherapeutic ((131)I) agent. CLR1404 analogs displayed prolonged tumor-selective retention in 55 in vivo rodent and human cancer and cancer stem cell models. (131)I-CLR1404 also displayed efficacy (tumor growth suppression and survival extension) in a wide range of human tumor xenograft models. Human PET/CT (computed tomography) and SPECT (single-photon emission computed tomography)/CT imaging in advanced-cancer patients with (124)I-CLR1404 or (131)I-CLR1404, respectively, demonstrated selective uptake and prolonged retention in both primary and metastatic malignant tumors. Combined application of these chemically identical APC-based radioisosteres will enable personalized dual modality cancer therapy of using molecular (124)I-CLR1404 tumor imaging for planning (131)I-CLR1404 therapy.
Assuntos
Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Fosforilcolina/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Fosforilcolina/análogos & derivados , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND/OBJECTIVE: Standard laparoscopic adrenalectomy requires early control of the main adrenal vein; however, the small retroperitoneal working space is challenging for beginners to perform this maneuver. We report a technical modification of retroperitoneal laparoscopic adrenalectomy (RLA) for primary hyperaldosteronism (PHA) and the clinical outcomes. METHODS: A total of 38 RLAs were performed for the patients with PHA. The patients were placed in true lateral position with mild bending to expand the surgical field. Instead of attempting to control the main adrenal vein initially, we adopted a technical modification that manipulating and freeing the gland first before controlling the main adrenal vein. RESULTS: The RLAs were successfully performed in all but one case, which was converted to open surgery due to pancreatic injury. Mean operative time was 124 minutes and estimated blood loss was 74 ml. Mean maximal fluctuation of systolic blood pressure was 29 mmHg. For the right-side RLA, less operative time (113.5 vs. 137.9 minutes) and estimated blood loss (59.5 vs. 91.2 ml) were noted compared with the left-side procedure. Postoperative complications included cerebrovascular accident in one patient, one surgical site hematoma, and two patients had postoperative fever. Potassium level returned to normal in all patients and 70% of the patients reduced their antihypertensives. CONCLUSION: Technical modification RLA for PHA without initial control of the main adrenal vein is a safe and feasible procedure. No vigorous blood pressure fluctuation was intraoperatively noted. No vascular injury occurred. Moreover, the right-side procedure became easier.