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Background: A functioning arteriovenous (AV) access is essential for hemodialysis efficiency and the quality of life in hemodialysis patients. Blood osteoprotegerin (OPG) and soluble receptor activator of nuclear factor kappa B ligand (RANKL) have been linked to cardiovascular diseases and vascular calcification. This study investigated the relationship between blood OPG, RANKL, and the occurrence of AV access thrombosis., Methods: This prospective cohort study was conducted from August 2016 to August 2021 and included patients undergoing prevalent hemodialysis in two hospital-based hemodialysis units. Cox proportional hazards models and Kaplan-Meier analysis were used to evaluate the association between blood OPG, RANKL, and AV access (AV fistula [AVF] and AV graft [AVG]) outcomes., Results: A total of 333 hemodialysis patients were enrolled, with an AV access thrombosis rate of 22.2%. Cox regression identified several factors associated with AV access thrombosis: AV access type (AVF vs. AVG; hazard ratio [HR], 0.24; p < 0.001), C-reactive protein (HR, 1.07; p = 0.002), and log-transformed OPG (HR, 5.52; p = 0.005). Subgroup analysis revealed high log-transformed OPG and RANKL were associated with AVF thrombosis (HR, 10.77; p = 0.002 and HR, 3.26; p = 0.009, respectively), while high C-reactive protein increased the risk of AVG thrombosis (HR, 1.31; p < 0.001). Kaplan-Meier analysis showed that patients with AVF in the highest tertile of log OPG (>402 pg/mL) had the highest AVF thrombosis incidence (p = 0.03)., Conclusion: High blood OPG was associated with AV access thrombosis, particularly in the AVF.

Background: The early detection of arteriovenous (AV) access dysfunction is crucial for maintaining the patency of vascular access. This study aimed to use deep learning to predict AV access malfunction necessitating further vascular management. Methods: This prospective cohort study enrolled prevalent hemodialysis (HD) patients with an AV fistula or AV graft from a single HD center. Their AV access bruit sounds were recorded weekly using an electronic stethoscope from three different sites (arterial needle site, venous needle site, and the midpoint between the arterial and venous needle sites) before HD sessions. The audio signals were converted to Mel spectrograms using Fourier transformation and utilized to develop deep learning models. Three deep learning models, (1) Convolutional Neural Network (CNN), (2) Convolutional Recurrent Neural Network (CRNN), and (3) Vision Transformers-Gate Recurrent Unit (ViT-GRU), were trained and compared to predict the likelihood of dysfunctional AV access. Results : Total 437 audio recordings were obtained from 84 patients. The CNN model outperformed the other models in the test set, with an F1 score of 0.7037 and area under the receiver operating characteristic curve (AUROC) of 0.7112. The Vit-GRU model had high performance in out-of-fold predictions, with an F1 score of 0.7131 and AUROC of 0.7745, but low generalization ability in the test set, with an F1 score of 0.5225 and AUROC of 0.5977. Conclusions: The CNN model based on Mel spectrograms could predict malfunctioning AV access requiring vascular intervention within 10 days. This approach could serve as a useful screening tool for high-risk AV access., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Background: Conflicting evidence exists regarding the relationship between socioeconomic status and access to or outcomes after kidney transplantation. This study analyzed the effects of individual and neighborhood socioeconomic status on kidney transplant access and outcomes in Taiwan., Methods: We used a retrospective cohort study design and performed comparisons using the Cox proportional hazards model after adjusting for risk factors. Data were collected from the National Health Insurance Bureau of Taiwan data (2003-2012)., Results: Patients with high individual and neighborhood socioeconomic status had higher chances of receiving kidney transplants than those with low individual and neighborhood socioeconomic status [adjusted hazard ratio (aHR) = 2.04; 95% CI: (1.81-2.31), p < 0.001]. However, there were no significant differences in post-transplant graft failure or patient mortality in Taiwan between individuals of varying socioeconomic status after five years. When we stratified kidney transplants by domestic and overseas transplantation, there were no significant differences in post-transplant mortality and graft failure, but individuals who received a kidney graft in Taiwan with high individual and neighborhood socioeconomic status experienced lower risks of graft failure (aHR = 0.55; [95% CI 0.33-0.89], p = 0.017)., Conclusion: A relevant disparity exists in accessing kidney transplantation in Taiwan, depending on individual and neighborhood socioeconomic status. However, results post transplantation were not different after five years. Improved access to waitlisting, education, and welfare support may reduce disparities., (© 2024. The Author(s).)

Introduction: Diabetic nephropathy (DN) is a severe diabetes mellitus (DM) complication that contributes to medical and financial burdens. This study aimed to investigate risk factors for DN among type 2 diabetes mellitus (T2DM) patients by stratifying the participants based on the presence of metabolic syndrome (MetS)., Materials and Methods: Between June 2017 and June 2022, Taiwan Hospital was chosen for this retrospective case-control study. Following the completion of a standardized interview and the donation of blood samples for this study, participants were divided into two groups according to whether they had MetS. We contrasted how the potential DN-related factors impacted these two groups., Results: A total of 1212 patients were included, and 639 patients (52.7%) had MetS. Multivariable analysis showed that the level of educational qualifications, fasting glucose, and uric acid (UA) were associated with DN. However, chewing betel nut behavior, higher systolic blood pressure (SBP), and higher glycated hemoglobin (HbA1c) were found to be risk factors of DN among the patients who had both T2DM and MetS. Notably, betel nut chewing increased the chance of DN in T2DM patients with MetS., Conclusions: This study found that the level of education, chewing betel nut behavior, HbA1c, fasting glucose, SBP, and UA were significant risk factors for the development of DN in diabetic individuals with concurrent MetS. Our research reveals that managing the aforementioned risk factors is crucial to lowering the prevalence of DN, particularly in individuals with lower levels of education.

Background: Obesity is a major risk factor for diabetes mellitus (DM), which is in turn a major risk factor for cardiovascular diseases such as coronary artery disease and stroke. As few studies have investigated sex differences in the association between obesity and incidence of DM, the aim of this longitudinal study was to explore this issue in a large group of Taiwanese participants., Methods: A total of 24,346 participants were enrolled in this study, of whom 8,334 (mean age, 50.6 ± 11.0 years) were male and 16,012 (mean age, 50.5 ± 10.1 years) were female. The following obesity-related indices were studied: body mass index, waist-to-height ratio, waist-to-hip ratio (WHR), body roundness index, conicity index (CI), body adiposity index, abdominal volume index, lipid accumulation product (LAP), and visceral adiposity index (VAI)., Results: The analysis showed significant associations between all of these indices with incidence of DM (all p < 0.001). In the male participants, the strongest predictors for incidence of DM were LAP (AUC = 0.692), WHtR (AUC = 0.684), and WHR (AUC = 0.683). In the female participants, the strongest predictors were LAP (AUC = 0.744), WHtR (AUC = 0.710) and VAI (AUC = 0.710), followed by BRI (AUC = 0.708)., Conclusion: Strong associations were found between the studied obesity-related indices and incidence of DM, and sex differences were found. Hence, to better control DM, reducing body weight may be beneficial in addition to lifestyle modifications, diet control, and pharmacological interventions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Chung, Liu, Wu, Huang and Chen.)

Adverse renal effects of systemic vascular endothelial growth factor (VEGF) inhibitor treatment are well documented. We aimed to identify associations between intravitreal VEGF inhibitor use and renal function decline in patients with diabetic retinopathy. We included 625 patients with diabetic retinopathy for regular renal function follow-ups and grouped them according to intravitreal therapy (67 with and 558 without treatment). We used a generalized estimating equation model to identify renal function decline risk factors. Increased age ( p = 0.02), insulin use ( p = 0.01), hypertension ( p < 0.01), and ischemic heart disease ( p < 0.01) were associated with significantly decreased estimated glomerular filtration rates (eGFRs) in patients with diabetic retinopathy after 1-year follow-up. Compared to the control group, patients who received intravitreal VEGF inhibitor injections showed a declining eGFR trend in the repeated measurement model without statistical significance ( p = 0.06). In subgroup analysis, patients with initial eGFR ≤ 30 mL/min/1.73 m 2 who received intravitreal VEGF inhibitors had significantly decreased renal function ( p < 0.01) compared to those without treatment. Intravitreal VEGF inhibitor injection was associated with renal function deterioration among patients with diabetic retinopathy and advanced chronic kidney disease. Strategies to monitor renal function after treatment should be considered in these high-risk populations.

The global prevalence and incidence of chronic kidney disease (CKD) continue to increase. Whether hyperuricemia is an independent risk factor for renal progression and whether there are sex differences in the relationships between serum uric acid (UA) and a decline in renal function are unclear. Therefore, in this longitudinal study, we aimed to explore these relationships in a large cohort of around 27,000 Taiwanese participants in the Taiwan Biobank (TWB), and also to identify serum UA cutoff levels in men and women to predict new-onset CKD. A total of 26,942 participants with a median 4 years of complete follow-up data were enrolled from the TWB. We excluded those with CKD (estimated glomerular filtration rate <60 mL/min/1.73 m2) at baseline (n = 297), and the remaining 26,645 participants (males: 9356; females: 17,289) were analyzed. The participants who developed CKD during follow-up were defined as having incident new-onset CKD, and those with a serum UA level >7 mg/dL in males and >6 mg/dL in females were classified as having hyperuricemia. After multivariable analysis, hyperuricemia (odds ratio [OR], 2.541; 95% confidence interval [CI], 1.970−3.276; p < 0.001) was significantly associated with new-onset CKD. Furthermore, in the male participants (n = 9356), hyperuricemia (OR, 1.989; 95% CI, 1.440−2.747; p < 0.001), and quartile 4 of UA (vs. quartile 1; OR, 2.279; 95% CI, 1.464−3.547; p < 0.001) were significantly associated with new-onset CKD, while in the female participants (n = 17,289), hyperuricemia (OR, 3.813; 95% CI, 2.500−5.815; p < 0.001), quartile 3 of UA (vs. quartile 1; OR, 3.741; 95% CI, 1.250−11.915; p = 0.018), and quartile 4 of UA (vs. quartile 1; OR, 12.114; 95% CI, 14.278−34.305; p < 0.001) were significantly associated with new-onset CKD. There were significant interactions between hyperuricemia and sex (p = 0.024), and quartiles of serum UA and sex (p = 0.010) on new-onset CKD. Hyperuricemia was associated with new-onset CKD in the enrolled participants, and the interactions between hyperuricemia and sex were statistically significant. Hyperuricemia was more strongly associated with new-onset CKD in the women than in the men.

While the liver, specifically hepatocytes, are widely accepted as the main source of hepatitis C virus (HCV) production, the role of the liver/hepatocytes in clearance of circulating HCV remains unknown. Frequent HCV kinetic data were recorded and mathematically modeled from five liver transplant patients throughout the anhepatic (absence of liver) phase and for 4 hr post-reperfusion. During the anhepatic phase, HCV remained at pre-anhepatic levels ( n = 3) or declined ( n = 2) with t 1/2 ~1 hr. Immediately post-reperfusion, virus declined in a biphasic manner in four patients consisting of a rapid decline ( t 1/2 = 5 min) followed by a slower decline ( t 1/2 = 67 min). Consistent with the majority of patients in the anhepatic phase, when we monitored HCV clearance at 37°C from culture medium in the absence/presence of chronically infected hepatoma cells that were inhibited from secreting HCV, the HCV t 1/2 in cell culture was longer in the absence of chronically HCV-infected cells. The results suggest that the liver plays a major role in the clearance of circulating HCV and that hepatocytes may be involved., Competing Interests: LS, MN, NS, GC, GS, TC, EC, SP, AP, SC, SU, HD No competing interests declared, XF XF acted as advisor for Gilead and AbbVie

Patients with end-stage renal disease have a high prevalence of cardiovascular disease. Chest radiography can be used to assess cardiothoracic ratio (CTR) and aortic arch calcification (AoAC). The aims of this longitudinal follow-up study were to investigate factors associated with changes in CTR and AoAC and understand whether these changes are associated with overall and cardiovascular mortality in hemodialysis (HD) patients. We enrolled 260 patients undergoing HD who had at least two available chest X-rays from 2008 to 2015. CTR and AoAC were assessed in each patient using measurements from baseline and annual chest X-rays. The CTR increased from 49.05% to 51.86% and the AoAC score increased from 3.84 to 9.73 over 7 years. The estimated slopes were 0.24 ( p < 0.0001) for CTR and 0.08 ( p = 0.0441) for AoAC. Increased AoAC, older age, female sex, coronary artery disease, and decreased albumin were associated with an increase in CTR, and older age, cerebrovascular disease, decreased albumin, increased Kt/V, and the use of antiplatelet agents were associated with an increase in AoAC. During follow-up, 136 of the 260 (52.3%) patients died, of whom 72 died due to cardiovascular causes. The change in CTR was greater in those who died ( p = 0.0125) than in those who survived. The AoAC score was also higher in those who died than in those who survived, although there was no significant difference in the change in AoAC between the two groups ( p = 0.8035). CTR and AoAC increased significantly over time in the HD patients in this longitudinal follow-up study, and the change in CTR was greater in those who died than in those who survived. Chest radiography is a simple and useful tool to assess the progression of CTR and AoAC as a prognostic marker.

Patients with end-stage renal disease have a higher risk of cardiovascular morbidity and mortality. In this study, we investigated the predictive ability of a combination of cardiothoracic ratio (CTR) and aortic arch calcification (AoAC) for overall and cardiovascular mortality in patients receiving hemodialysis. We also evaluated the predictive power of AoAC and CTR for clinical outcomes. A total of 365 maintenance hemodialysis patients were included, and AoAC and CTR were measured using chest radiography at enrollment. We stratified the patients into four groups according to a median AoAC score of three and CTR of 50%. Multivariable Cox proportional hazards analysis was used to identify the risk factors of mortality. The predictive performance of the model for clinical outcomes was assessed using the χ2 test. Multivariable analysis showed that, compared to the AoAC < 3 and CTR < 50% group, the AoAC ≥ 3 and CTR < 50% group (hazard ratio [HR], 4.576; p < 0.001), and AoAC ≥ 3 and CTR ≥ 50% group (HR, 5.912; p < 0.001) were significantly associated with increased overall mortality. In addition, the AoAC < 3 and CTR ≥ 50% (HR, 3.806; p = 0.017), AoAC ≥ 3 and CTR < 50% (HR, 4.993; p = 0.002), and AoAC ≥ 3 and CTR ≥ 50% (HR, 8.614; p < 0.001) groups were significantly associated with increased cardiovascular mortality. Furthermore, adding AoAC and CTR to the basic model improved the predictive ability for overall and cardiovascular mortality. The patients who had a high AoAC score and cardiomegaly had the highest overall and cardiovascular mortality among the four groups. Furthermore, adding AoAC and CTR improved the predictive ability for overall and cardiovascular mortality in the hemodialysis patients.

Whereas the mode of action of lamivudine (LAM) against hepatitis B virus (HBV) is well established, the inhibition mechanism(s) of interferon alpha (IFN-α) is less completely defined. To advance our understanding, we mathematically modeled HBV kinetics during 14-day pegylated IFN-α-2a (pegIFN), LAM, or pegIFN-plus-LAM (pegIFN+LAM) treatment of 39 chronically HBV-infected humanized uPA/SCID chimeric mice. Serum HBV DNA and intracellular HBV DNA were measured frequently. We developed a multicompartmental mathematical model and simultaneously fit it to the serum and intracellular HBV DNA data. Unexpectedly, even in the absence of an adaptive immune response, a biphasic decline in serum HBV DNA and intracellular HBV DNA was observed in response to all treatments. Kinetic analysis and modeling indicate that the first phase represents inhibition of intracellular HBV DNA synthesis and secretion, which was similar under all treatments with an overall mean efficacy of 98%. In contrast, there were distinct differences in HBV decline during the second phase, which was accounted for in the model by a time-dependent inhibition of intracellular HBV DNA synthesis, with the steepest decline observed during pegIFN+LAM treatment (1.28/day) and the slowest (0.1/day) during pegIFN monotherapy. Reminiscent of observations in patients treated with pegIFN and/or LAM, a biphasic HBV decline was observed in treated humanized mice in the absence of an adaptive immune response. Interestingly, combination treatment did not increase the initial inhibition of HBV production but rather enhanced second-phase decline, providing insight into the dynamics of HBV treatment response and the mode of action of IFN-α against HBV. IMPORTANCE Chronic hepatitis B virus (HBV) infection remains a global health care problem, as we lack sufficient curative treatment options. Elucidating the dynamics of HBV infection and treatment response at the molecular level could facilitate the development of novel, more effective HBV antivirals. Currently, the only well-established small animal HBV infection model available is the chimeric uPA/SCID mice with humanized livers; however, the HBV inhibition kinetics under pegylated IFN-α-2a (pegIFN) in this model system have not been determined in sufficient detail. In this study, viral kinetics in 39 humanized mice treated with pegIFN and/or lamivudine were monitored and analyzed using a mathematical modeling approach. We found that the main mode of action of IFN-α is blocking HBV DNA synthesis and that the majority of synthesized HBV DNA is secreted. Our study provides novel insights into HBV DNA dynamics within infected human hepatocytes.

Acoustic cardiography can provide simultaneous electrocardiography and acoustic cardiac data to assess the electronic and mechanical heart functions. The aim of this study was to assess whether changes in acoustic cardiographic parameters (ACPs) before and after hemodialysis (HD) are associated with overall and cardiovascular (CV) mortality in HD patients. A total of 162 HD patients was enrolled and ACPs were measured before and after HD, including left ventricular systolic time (LVST), systolic dysfunction index (SDI), third (S3) and fourth (S4) heart sounds, and electromechanical activation time (EMAT). During a follow-up of 2.9 years, 25 deaths occurred with 16 from CV causes. Multivariate analysis showed that high △SDI (per 1; hazard ratio [HR], 2.178; 95% confidence interval [CI], 1.189-3.990), high △EMAT (per 1%; HR, 2.218; 95% CI 1.382-3.559), and low △LVST (per 1 ms; HR, 0.947; 95% CI 0.912-0.984) were independently associated with increased overall mortality. In addition, high △EMAT (per 1%; HR, 2.141; 95% CI 1.117-4.102), and low △LVST (per 1 ms; HR, 0.777; 95% CI 0.637-0.949) were associated with increased CV mortality. In conclusion, the changes in ACPs before and after HD may be a useful clinical marker and stronger prognostic marker of overall and CV mortality than ACPs before HD.

A light-field camera captures both the intensity and the direction of incoming light 1-5 . This enables a user to refocus pictures and afterwards reconstruct information on the depth of field. Research on light-field imaging can be divided into two components: acquisition and rendering. Microlens arrays have been used for acquisition, but obtaining broadband achromatic images with no spherical aberration remains challenging. Here, we describe a metalens array made of gallium nitride (GaN) nanoantennas 6 that can be used to capture light-field information and demonstrate a full-colour light-field camera devoid of chromatic aberration. The metalens array contains an array of 60 × 60 metalenses with diameters of 21.65 μm. The camera has a diffraction-limited resolution of 1.95 μm under white light illumination. The depth of every object in the scene can be reconstructed slice by slice from a series of rendered images with different depths of focus. Full-colour, achromatic light-field cameras could find applications in a variety of fields such as robotic vision, self-driving vehicles and virtual and augmented reality.

The second harmonic generation (SHG) of vertical and planar split-ring resonators (SRRs) that are broken centro-symmetry configurations at the interface of metal surface and air is investigated. Strong interactions, better electromagnetic field confinements, and less leakage into the substrate for vertical SRRs are found. Experimental results show a 2.6-fold enhancement of SHG nonlinearity, which is in good agreement with simulations and calculations. Demonstrations of 3D metastructures and vertical SRRs with strong SHG nonlinearity majorly result from magnetic dipole and electric quadrupole clearly provides potential applications for photonics and sensing., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Denosumab, a novel agent that inhibits osteoclasts, reduces the risk of fracture in patients with osteoporosis. However, worsening of hypophosphatemia and other symptoms may be induced by denosumab in patients with pre-existing hypophosphatemic osteomalacia. A 58-year-old man with hepatitis B presented with diffuse bone pain and muscle weakness. Denosumab was prescribed by the orthopedist according to documented low bone mass and spine compression fracture. After administering denosumab, the patient's bone pain worsened, and he later developed a right tibia stress fracture. His condition was diagnosed as adult-onset hypophosphatemic osteomalacia complicated by multiple bone fractures, which resulted from Fanconi syndrome with proximal tubulopathy due to tenofovir disoproxil fumarate (TDF) treatment for his hepatitis B. Denosumab use leads to aggressive hypophosphatemic osteomalacia and the complication of stress fractures, because of its effects on bone resorption. Physicians should be aware that in patients with chronic hepatitis B monoinfection who are administered TDF therapy, bone pain or fracture is possible but preventable by timely monitoring of serum phosphate levels. Denosumab should not be used in patients with untreated osteomalacia or vitamin D deficiency, as it may lead not only to hypocalcemia but also to hypophosphatemia in these patients.

Background: It is unclear if anaesthesia maintenance with propofol is advantageous or beneficial over inhalational agents. This study is intended to compare the effects of propofol vs. inhalational agents in maintaining general anaesthesia on patient-relevant outcomes and patient satisfaction., Methods: Studies were identified by electronic database searches in PubMed™, EMBASE™ and the Cochrane™ library between 01/01/1985 and 01/08/2016. Randomized controlled trials (RCTs) of peer-reviewed journals were studied. Of 6688 studies identified, 229 RCTs were included with a total of 20,991 patients. Quality control, assessment of risk of bias, meta-bias, meta-regression and certainty in evidence were performed according to Cochrane. Common estimates were derived from fixed or random-effects models depending on the presence of heterogeneity. Post-operative nausea and vomiting (PONV) was the primary outcome. Post-operative pain, emergence agitation, time to recovery, hospital length of stay, post-anaesthetic shivering and haemodynamic instability were considered key secondary outcomes., Results: The risk for PONV was lower with propofol than with inhalational agents (relative risk (RR) 0.61 [0.53, 0.69], p < 0.00001). Additionally, pain score after extubation and time in the post-operative anaesthesia care unit (PACU) were reduced with propofol (mean difference (MD) - 0.51 [- 0.81, - 0.20], p = 0.001; MD - 2.91 min [- 5.47, - 0.35], p = 0.03). In turn, time to respiratory recovery and tracheal extubation were longer with propofol than with inhalational agents (MD 0.82 min [0.20, 1.45], p = 0.01; MD 0.70 min [0.03, 1.38], p = 0.04, respectively). Notably, patient satisfaction, as reported by the number of satisfied patients and scores, was higher with propofol (RR 1.06 [1.01, 1.10], p = 0.02; MD 0.13 [0.00, 0.26], p = 0.05). Secondary analyses supported the primary results., Conclusions: Based on the present meta-analysis there are several advantages of anaesthesia maintenance with propofol over inhalational agents. While these benefits result in an increased patient satisfaction, the clinical and economic relevance of these findings still need to be addressed in adequately powered prospective clinical trials.

Chimeric urokinase type plasminogen activator (uPA)/severely severe combined immunodeficiency (SCID) mice reconstituted with humanized livers are useful for studying hepatitis B virus (HBV) infection in the absence of an adaptive immune response. However, the detailed characterization of HBV infection kinetics necessary to enable in-depth mechanistic studies in this in vivo HBV infection model is lacking. To characterize HBV kinetics post-inoculation (p.i.) to steady state, 42 mice were inoculated with HBV. Serum HBV DNA was frequently measured from 1 minute to 63 days p.i. Total intrahepatic HBV DNA, HBV covalently closed circular DNA (cccDNA), and HBV RNA was measured in a subset of mice at 2, 4, 6, 10, and 13 weeks p.i. HBV half-life (t 1/2 ) was estimated using a linear mixed-effects model. During the first 6 hours p.i., serum HBV declined in repopulated uPA/SCID mice with a t 1/2 = 62 minutes (95% confidence interval [CI] = 59-67). Thereafter, viral decline slowed followed by a 2-day lower plateau. Subsequent viral amplification was multiphasic with an initial mean doubling time of t 2 = 8 ± 3 hours followed by an interim plateau before prolonged amplification (t 2 = 2 ± 0.5 days) to a final HBV steady state of 9.3 ± 0.3 log copies (cps)/mL. Serum HBV and intrahepatic HBV DNA were positively correlated (R 2 = 0.98)., Conclusion: HBV infection in uPA/SCID chimeric mice is highly dynamic despite the absence of an adaptive immune response. Serum HBV t 1/2 in humanized uPA/SCID mice was estimated to be ∼1 hour regardless of inoculum size. The HBV acute infection kinetics presented here is an important step in characterizing this experimental model system so that it can be effectively used to elucidate the dynamics of the HBV life cycle and thus possibly reveal effective antiviral drug targets. (Hepatology 2018)., (© 2018 by the American Association for the Study of Liver Diseases.)

The toroidal dipole is a localized electromagnetic excitation independent from the familiar magnetic and electric dipoles. It corresponds to currents flowing along minor loops of a torus. Interference of radiating induced toroidal and electric dipoles leads to anapole, a nonradiating charge-current configuration. Interactions of induced toroidal dipoles with electromagnetic waves have recently been observed in artificial media at microwave, terahertz, and optical frequencies. Here, we demonstrate a quasi-planar plasmonic metamaterial, a combination of dumbbell aperture and vertical split-ring resonator, that exhibits transverse toroidal moment and resonant anapole behavior in the optical part of the spectrum upon excitation with a normally incident electromagnetic wave. Our results prove experimentally that toroidal modes and anapole modes can provide distinct and physically significant contributions to the absorption and dispersion of slabs of matter in the optical part of the spectrum in conventional transmission and reflection experiments.

Background: Soil organic carbon (SOC) and carbon (C) functional groups in different particle-size fractions are important indicators of microbial activity and soil decomposition stages under wildfire disturbances. This research investigated a natural Tsuga forest and a nearby fire-induced grassland along a sampling transect in Central Taiwan with the aim to better understand the effect of forest wildfires on the change of SOC in different soil particle scales. Soil samples were separated into six particle sizes and SOC was characterized by solid-state 13 C nuclear magnetic resonance spectroscopy in each fraction., Results: The SOC content was higher in forest than grassland soil in the particle-size fraction samples. The O-alkyl-C content (carbohydrate-derived structures) was higher in the grassland than the forest soils, but the alkyl-C content (recalcitrant substances) was higher in forest than grassland soils, for a higher humification degree (alkyl-C/O-alkyl-C ratio) in forest soils for all the soil particle-size fractions., Conclusions: High humification degree was found in forest soils. The similar aromaticity between forest and grassland soils might be attributed to the fire-induced aromatic-C content in the grassland that offsets the original difference between the forest and grassland. High alkyl-C content and humification degree and low C/N ratios in the fine particle-size fractions implied that undecomposed recalcitrant substances tended to accumulate in the fine fractions of soils.

Background: Type 1 diabetes mellitus (T1D) is mediated by autoaggressive T effector cells with an underlying regulatory T-cell (Treg) defect. Vitamin D deficiency is highly prevalent in T1D, which can aggravate immune dysfunction. High-dose vitamin D treatment may enhance Tregs and improve metabolism in T1D patients., Methods: In a randomized double-blind placebo-controlled trial with crossover design, patients received either for 3 months cholecalciferol 4000 IU/d followed by 3 months placebo or the sequential alternative. Thirty-nine T1D patients (19 women and 20 men) completed the trial., Results: Primary outcome was a change of Tregs, secondary HbA1C, and insulin demand. Effects were evaluated based on intra-individual changes between treatment and placebo periods for outcome measures. Exploratory analyses included vitamin D system variant genotyping and C-peptide measurements. Median 25(OH)D 3 increased to 38.8 ng/ml with males showing a significantly stronger increase (p = .003). T-lymphocyte profiles did not change significantly (p > 2); however, the intra-individual change of Tregs between males and females was different with a significantly stronger increase in men (p = .017), as well as between genotypes of the vitamin D receptor (Apa, Taq, and Bsm: genotypes aa, TT, and bb; p = .004-0.015). Insulin demands declined significantly (p = .003-.039) and HbA1C improved (p < .001). Random C-peptide levels were low but rising (median, 0.125 ng/ml; range, 0.02-0.3) in 6 patients. No toxicity was observed., Conclusion: A daily vitamin D dose of 4000 IU for 3 months was well tolerated and enhanced Tregs in males. Glucometabolic control improved in all. Subsequent larger trials need to address ß-cell function and genotyping for individualized vitamin D doses., (Copyright © 2016 John Wiley & Sons, Ltd.)

The study and application of human pluripotent stem cells (hPSCs) will be enhanced by the availability of well-characterized monoclonal antibodies (mAbs) detecting cell-surface epitopes. Here, we report generation of seven new mAbs that detect cell surface proteins present on live and fixed human ES cells (hESCs) and human iPS cells (hiPSCs), confirming our previous prediction that these proteins were present on the cell surface of hPSCs. The mAbs all show a high correlation with POU5F1 (OCT4) expression and other hPSC surface markers (TRA-160 and SSEA-4) in hPSC cultures and detect rare OCT4 positive cells in differentiated cell cultures. These mAbs are immunoreactive to cell surface protein epitopes on both primed and naive state hPSCs, providing useful research tools to investigate the cellular mechanisms underlying human pluripotency and states of cellular reprogramming. In addition, we report that subsets of the seven new mAbs are also immunoreactive to human bone marrow-derived mesenchymal stem cells (MSCs), normal human breast subsets and both normal and tumorigenic colorectal cell populations. The mAbs reported here should accelerate the investigation of the nature of pluripotency, and enable development of robust cell separation and tracing technologies to enrich or deplete for hPSCs and other human stem and somatic cell types. Stem Cells 2017;35:626-640., (© 2016 The Authors Stem Cells published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.)

Background: Metabolic syndrome (MetS) contains a cluster of cardiovascular risk factors. People with MetS are more susceptible to cardiovascular disease, diabetes mellitus, and cancer. Endothelin-1 (ET-1) and matrix metallopeptidase-9 (MMP-9) have been implicated in the development of cardiovascular diseases, diabetes mellitus and cancers. This cross-sectional study aimed to examine the association of ET-1 and MMP-9 with MetS in middle-aged and older Hong Kong Chinese adults., Methods: 149 adults aged 50 to 92 (n = 75 for non-MetS group and n = 74 for MetS group) were examined. All subjects were screened for MetS according to the diagnostic guideline of the United States National Cholesterol Education Program (NCEP) Expert Panel Adult Treatment Panel (ATP) III criteria. Serum levels of ET-1 and MMP-9 were measured. Independent t test was used to detect differences between non-MetS and MetS groups and between subjects with or without certain metabolic abnormality. The association of the serum concentration of MMP-9 and ET-1 with MetS parameters were examined by Pearson's correlation analysis., Results: Serum level of ET-1 is higher in MetS-positive subjects and in subjects with high blood pressure, elevated fasting blood glucose, and central obesity. The serum concentration of MMP-9 is higher in subjects positively diagnosed with MetS and subjects with high blood pressure, elevated fasting blood glucose, low blood high-density lipoprotein-cholesterol (HDL-C), high blood triglycerides, and central obesity. Correlation analyses revealed that serum concentration of ET-1 is positively correlated to systolic blood pressure, waist circumference, fasting blood glucose, and age whereas it is negatively correlated to HDL-C. MMP-9 is positively correlated to systolic blood pressure, waist circumference, fasting blood glucose, and age whereas it is negatively correlated to HDL-C., Conclusion: Serum ET-1 is higher in subjects with hypertension, hyperglycemia, central obesity or MetS. Serum MMP-9 is higher in subjects diagnosed with MetS or having either one of the MetS parameters. Both circulating levels of ET-1 and MMP-9 are correlated to systolic blood pressure, waist circumference, fasting blood glucose, HDL-C, and age. Further research is needed to fully dissect the role of ET-1 and MMP-9 in the development of cancers, diabetes and cardiovascular disease in relation to MetS.

Megadose vitamin C (Vc) is one of the most enduring alternative treatments for diverse human diseases and is deeply engrafted in popular culture. Preliminary studies in the 1970s described potent effects of Vc on prolonging the survival of patients with terminal cancer, but these claims were later criticized. An improved knowledge of the pharmacokinetics of Vc and recent reports using cancer cell lines have renewed the interest in this subject. Despite these findings, using Vc as an adjuvant for anticancer therapy remains questionable, among other things because there is no proper mechanistic understanding. Here, we show that a Warburg effect triggered by activation of the hypoxia-inducible factor (HIF) pathway greatly enhances Vc-induced toxicity in multiple cancer cell lines, including von Hippel-Lindau (VHL)-defective renal cancer cells. HIF increases the intracellular uptake of oxidized Vc through its transcriptional target glucose transporter 1 (GLUT1), synergizing with the uptake of its reduced form through sodium-dependent Vc transporters. The resulting high levels of intracellular Vc induce oxidative stress and massive DNA damage, which then causes metabolic exhaustion by depleting cellular ATP reserves. HIF-positive cells are particularly sensitive to Vc-induced ATP reduction because they mostly rely on the rather inefficient glycolytic pathway for energy production. Thus, our experiments link Vc-induced toxicity and cancer metabolism, providing a new explanation for the preferential effect of Vc on cancer cells.

Background: The Chamaecyparis forest is a valuable natural resource in eastern Asia. The characteristics of soil humic substances and the influence of environmental factors in natural Chamaecyparis forests in subtropical mountain regions are poorly understood. The study site of a perhumid Chamaecyparis forest is in the Yuanyang Lake Preserved Area in northcentral Taiwan. We collected samples from organic horizons (Oi, Oe and Oa) and from the surface horizon (O/A horizon) at the summit, footslope and lakeshore to characterize the composition of the soil organic matter. Samples of organic horizons were dried and ground, and those of the O/A horizon were passed through wet sieving for different particle-size fractions before analysis. The C chemical structure in the samples was determined with CP/MAS 13 C NMR spectra., Results: The ratios of alkyl-C/O-alkyl-C and aromaticity increased with decomposition of litter from the Oi, Oe, to Oa horizon. The ratio of alkyl-C/O-alkyl-C also increased from coarse (> 250 μm) to very fine (< 2 μm) particle fractions, which indicates increased humification of soil organic matter (SOM) in the fine-sized fractions. However, aromaticity tended to decrease with decreasing particle size, so it may not be useful in evaluating SOM humification of different particle-size fractions., Conclusions: The humification degree of the samples from O horizons and different particle-size fractions of the O/A horizon showed no gradient change with change in topography. This prevalent slow decomposition of organic matter in these perhumid climate conditions may narrow the difference in humification from the summit to lakeshore.

Background: Improvements in surgical techniques have allowed us to achieve primary closure in a high percentage of large abdominal hernia repairs. However, postoperative wound complications remain common. The benefits of negative-pressure wound therapy (NPWT) in the management of open abdominal wounds are well described in the literature. Our study investigates the effects of incisional NPWT after primary closure of the abdominal wall., Methods: A retrospective chart review was performed for the period between September 2008 and May 2011 to analyze the outcomes of patients treated postoperatively with incisional NPWT versus conventional dry gauze dressings. Patient information collected included history of abdominal surgeries, smoking status, and body mass index. Postoperative complications were analyzed using χ exact test and logistic regression analysis., Results: Fifty-six patients were included in this study; of them, 23 were treated with incisional NPWT, whereas 33 received conventional dressings. The rates of overall wound complications in groups I and II were 22% and 63.6%, respectively (P = 0.020). The rates of skin dehiscence were 9% and 39%, respectively (P = 0.014). Both outcomes achieved statistical significance. Rates of infection, skin and fat necrosis, seroma, and hernia recurrence were 4%, 9%, 0%, and 4% for group I and 6%, 18%, 12%, 9% for group II, respectively., Conclusions: This study suggests that incisional NPWT following abdominal wall reconstruction significantly improves rates of wound complication and skin dehiscence when compared with conventional dressings. Prospective, randomized, controlled studies are needed to further characterize the potential benefits of this therapy on wound healing after abdominal wall reconstruction.

Down syndrome (DS) is the most frequent cause of human congenital mental retardation. Cognitive deficits in DS result from perturbations of normal cellular processes both during development and in adult tissues, but the mechanisms underlying DS etiology remain poorly understood. To assess the ability of induced pluripotent stem cells (iPSCs) to model DS phenotypes, as a prototypical complex human disease, we generated bona fide DS and wild-type (WT) nonviral iPSCs by episomal reprogramming. DS iPSCs selectively overexpressed chromosome 21 genes, consistent with gene dosage, which was associated with deregulation of thousands of genes throughout the genome. DS and WT iPSCs were neurally converted at >95% efficiency and had remarkably similar lineage potency, differentiation kinetics, proliferation, and axon extension at early time points. However, at later time points DS cultures showed a twofold bias toward glial lineages. Moreover, DS neural cultures were up to two times more sensitive to oxidative stress-induced apoptosis, and this could be prevented by the antioxidant N-acetylcysteine. Our results reveal a striking complexity in the genetic alterations caused by trisomy 21 that are likely to underlie DS developmental phenotypes, and indicate a central role for defective early glial development in establishing developmental defects in DS brains. Furthermore, oxidative stress sensitivity is likely to contribute to the accelerated neurodegeneration seen in DS, and we provide proof of concept for screening corrective therapeutics using DS iPSCs and their derivatives. Nonviral DS iPSCs can therefore model features of complex human disease in vitro and provide a renewable and ethically unencumbered discovery platform., (Copyright © 2012 AlphaMed Press.)

Purpose: To report our results of computed tomography (CT)-guided interstitial high-dose-rate (HDR) brachytherapy (BRT) in the local treatment of inoperable primary and secondary liver malignancies., Methods and Materials: Between 2000 and 2009, 31 patients underwent a total of 42 BRT procedures for 36 hepatic lesions exceeding 4 cm and located adjacent to the liver hilum and bile duct bifurcation. The median tumor volume was 99 cm(3) (range, 46-1348 cm(3)). The median age was 64 years (range, 27-85 years). The HDR-BRT delivered a median total physical dose of 13.0 Gy (range, 7.0-32.0 Gy) in twice daily fractions of median 7.0 Gy (range, 4.0-10.0 Gy) in 14 patients and in once daily fractions of median 8.0 Gy (range, 7.0-14.0 Gy) in 17 patients., Results: The median followup was 13.3 months with an overall survival rate of 66% at 1 year. The local control rate for patients with metastatic lesions was 79%, 59%, and 59%, and for the subgroup with primary hepatic tumors 88%, 50%, and 50% at 1, 2, and 3 years, respectively. Severe side effects occurred in 4.7% of BRT procedures with no treatment-related deaths., Conclusions: Our results confirm CT-guided interstitial HDR-BRT to be a safe procedure for the local treatment of inoperable liver malignancies unsuitable for thermal ablation., (Copyright © 2012 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Background: The critical analysis of baseline factors has been found to be useful to predict virologic nonresponse (NR), relapse, or sustained virologic response (SVR) in patients infected with hepatitis C virus (HCV) who receive antiviral therapy. In the present retrospective study we tried to find out whether gamma-glutamyltranspeptidase (GGT) may be one of the baseline factors which are of special predictive power. We analyzed, in patients with different treatment outcomes, the predictive power of established baseline factors either in combination with GGT or by evaluating the predictive value of GGT independently., Methods: Individual data from 632 patients chronically infected with HCV type 1 (n = 561) or type 2/3 (n = 71) were analyzed. All patients had received their first course of antiviral therapy and were treated with pegylated interferon α-2a or -2b plus ribavirin., Results: In patients with HCV type 1, a multivariate multinomial logistic regression analysis identified low GGT (p < 0.0001), high cholesterol (p < 0.0001), age ≤ 40 years (p < 0.0001), high alanine aminotransferase (p = 0.0006), low viremia (p = 0.0014), and absence of cirrhosis (p = 0.0164) as independent predictors. While these baseline factors heralded improved virologic response, high GGT, in contrast, was significantly associated with NR (p < 0.0001). A strong correlation was found between log(10) GGT and a scoring variable S (r = -0.26 for prediction of SVR, p < 0.001; r = 0.11 for prediction of NR, p = 0.016) summarizing predictive information from other baseline factors., Conclusions: These findings prove the predictive sensitivity of GGT as an independent indicator of nonresponsiveness even at levels that are slightly above the normal range. This new predictive parameter may help to improve individualized therapy in HCV type-1 infection.

Background: Hepatitis C virus (HCV)/HIV co-infected patients have more rapid progression of liver fibrosis and only modest cure rates (sustained virologic responses, SVRs) when compared to HCV monoinfected patients., Method: We compared the virologic responses of either twice-weekly peginterferon-α-2a 180 μg/week (for 4 weeks, followed by weekly dosing) or weekly peginterferon-α-2a 180 μg/week, and weight-based ribavirin (1-1.2 g/day), among HIV/HCV co-infected genotype-1 individuals., Results: Patients receiving the investigational dosing had lower levels of HCV RNA at all time points after initiation of therapy. More patients on this arm achieved clinically relevant early virological responses at weeks 1, 2, 4, 12, and 24. The enhanced early virologic response observed with the investigational arm was associated with a higher induction of interferon-stimulated genes. This early double dose regimen also resulted in a rapid normalization of liver enzymes. Twice-weekly peginterferon-α-2a was associated with more frequent early virological responses with similar safety profiles when compared with standard therapy., Conclusion: Our results, when confirmed in larger randomized clinical trials, may provide a novel therapeutic approach to improve SVR among HIV/HCV co-infected patients, especially African-American patients.

Background: Ribavirin increases early and sustained virological response rates in patients chronically infected with HCV who receive pegylated interferon-α and novel HCV protease inhibitors., Methods: To better characterize antiviral efficacies of these upcoming therapies, Huh7 cells harbouring a subgenomic HCV replicon system were cultivated with various doses and combinations of ribavirin, interferon-α, and the protease inhibitors boceprevir and telaprevir. Antiviral efficacy parameters were estimated from HCV RNA decay, and synergistic effects of combination therapies were analysed with the Bliss independency model., Results: Single-drug antiviral activities showed dose-dependent HCV RNA reductions in replicon cells (50% inhibitory concentration of 386.16 μM, 81.67 IU, 0.44 μM and 0.81 μM after 48 h for ribavirin, interferon-α, boceprevir and telaprevir, respectively). For the dual combination of ribavirin with either boceprevir or telaprevir, no deviation from additivity was observed whereas the reduction of HCV RNA was synergistic for ribavirin with interferon-α (P<0.001). Triple combinations with ribavirin, interferon-α and protease inhibitors showed the most profound HCV RNA decay., Conclusions: The beneficial in vitro antiviral effect of ribavirin with interferon-α and novel HCV protease inhibitors demonstrates that ribavirin may be required as an antiviral backbone in the near future.

Human embryonic stem cells (hESC) are expected to provide revolutionary therapeutic applications and drug discovery technologies. In order for this to be achieved a reproducible, defined animal component free culture system is required for the scale-up production of undifferentiated hESC. In this work we have investigated the applicability of a recombinantly produced domain of human vitronectin as an extracellular matrix alternative to the common standards Geltrex or Matrigel. In addition we have validated an ascorbate free media capable of supporting CD30(low) populations of hESC through a multi-factorial analysis of bFGF and Activin A. The recombinant vitronectin domain combined with the ascorbate free media were capable of supporting 3 cell lines, MEL1, MEL2 and hES3 for 10 or more passages while maintaining hESC pluripotency markers and differentiation capacity. The culture method outlined here provides a platform for future investigation into growth factor and extracellular matrix effects on hESC maintenance prior to bioreactor scale-up., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

Vitamin C (ascorbate) is a widely used medium supplement in embryonic stem cell culture. Here, we show that ascorbate causes widespread, consistent, and remarkably specific DNA demethylation of 1,847 genes in human embryonic stem cells (hESCs), including important stem cell genes, with a clear bias toward demethylation at CpG island boundaries. We show that a subset of these DNA demethylated genes displays concomitant gene expression changes and that the position of the demethylated CpGs relative to the transcription start site is correlated to such changes. We further show that the ascorbate-demethylated gene set not only overlaps with gene sets that have bivalent marks, but also with the gene sets that are demethylated during differentiation of hESCs and during reprogramming of fibroblasts to induced pluritotent stem cells (iPSCs). Our data thus identify a novel link between ascorbate-mediated signaling and specific epigenetic changes in hESCs that might impact on pluripotency and reprogramming pathways.

Human embryonic stem cells (hESCs) and induced pluripotent stem cells have the ability to adapt to various culture conditions. Phenotypic and epigenetic changes brought about by the culture conditions can, however, have significant impacts on their use in research and in clinical applications. Here, we show that diploid hESCs start to express CD30, a biomarker for malignant cells in Hodgkin's disease and embryonal carcinoma cells, when cultured in knockout serum replacement (KOSR)-based medium, but not in fetal calf serum containing medium. We identify the commonly used medium additive, ascorbate, as the sole medium component in KOSR responsible for CD30 induction. Our data show that this epigenetic activation of CD30 expression in hESCs by ascorbate occurs through a dramatic loss of DNA methylation of a CpG island in the CD30 promoter. Analysis of the phenotype and transcriptome of hESCs that overexpress the CD30 signaling domain reveals that CD30 signaling leads to inhibition of apoptosis, enhanced single-cell growth, and transcriptome changes that are associated with cell signaling, lipid metabolism, and tissue development. Collectively, our data show that hESC culture media that contain ascorbate trigger CD30 expression through an epigenetic mechanism and that this provides a survival advantage and transcriptome changes that may help adapt hESCs to in vitro culture conditions.

Polycyclic aromatic hydrocarbons (PAHs), polychlorinated-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are some of the major organic contaminants emitted in municipal solid waste incinerators (MSWIs). The distribution of PAHs and PCDD/Fs in different MSWI unit ashes, including bottom residue (BR), fly ash pit (FAP), fabric filter (FF), semi-dryer absorber (SDA), economizer (EC) and super heater (SH), has seldom been discussed. Average PAHs content in ash samples from BR, FAP, FF, SDA, EC and SH were found to be 0.020, 0.237, 0.234, 0.125, 0.037 and 0.034 µg TEQ g(-1), respectively. In addition, the range of total emission factor from different unit ashes varied between 0.30-13.85 mg TEQ tonne(-1) of waste, low molecular weight compounds (2~3-ring) being the dominant species. Furthermore, PAHs in ashes were mainly found in BR (41%) and FAP (31%). The FAP ash included 18% of PAHs coming from FF ash. On the other hand, PCDD/Fs content in BR, FAP, FF, SDA, EC and SH was found to be 0.0329, 1.1589, 1.2807, 0.1476, 0.6868 and 0.0921 ng I-TEQ g(-1), respectively. PCDD/ Fs emission factors in this study ranged between 1.029-67.740 µg I-TEQ tonne(-1) of waste, most PCDD/Fs being present in FAP (55%). The FAP ash included 33% of PCDD/Fs coming from FF ash. Therefore, PCDD/Fs content in FAP and FF exceeded the legal limit of 1 ng I-TEQ g( -1); therefore, a solidification process is necessary before landfilling in Taiwan.

Background: Reconstructive techniques and protocols for limb salvage of upper extremity battlefield injuries remains poorly defined. Our study describes the types of flaps, the timing of reconstruction, and success rates of war upper extremity reconstruction during a 30-month period using the Bethesda limb salvage protocol., Methods: Soldiers with significant upper extremity injuries with complex open fractures from Operation Iraqi Freedom and Operation Enduring Freedom-Afghanistan who underwent tissue transfer flaps were reviewed (n = 26, free flaps n = 6). Data analysis included mechanism of injury, associated injuries, types of flap, postoperative complications, wound infection rates, and outcome data., Results: The cause of injury consisted of improvised explosive device (61%), rocket-propelled grenades (15%), motor vehicle crash (8%), land mine (8%), and gunshot wound (4%). Mean age was 25 years. Mean number of prereconstructive washouts was six (range, 3-22). Forty-six percent of wounds were culture positive at admission (75% were Acinetobacter species). All patients had other coexisting extremity, trunk or facial injuries. Average time to flap reconstruction was 31 days (range, 9-161). In 66% of the cases, a fasciocutaneous flap was used, and in the remaining cases, muscle (19%) and adipofascial (15%) flaps were performed. Flap success rate was 96%, with one flap loss because of venous congestion (managed with limb shortening). Infection rate was 8%. Complete coverage was achieved in all upper extremity wounds and early occupational therapy resulted in improved return to function., Conclusions: Despite massive bone and soft tissue defects, high preoperative wound colonization, and delays in definitive reconstruction, devastating war wounds can be successfully reconstructed in the subacute period with low flap failure, infection, and amputation rates.

Background: War wounds associated with Operation Iraqi Freedom have created a unique reconstructive challenge. The objective of this study was to report and analyze the timing and success rates of lower extremity reconstruction associated with devastating war wounds., Methods: A retrospective review was conducted of injured personnel requiring extremity flap reconstruction at the National Naval Medical Center over a 30-month period. Collected data included mechanism of injury, time from initial injury to closure, number of prereconstruction wound washouts, types of flap, flap failures, associated injuries, and wound culture characteristics., Results: From September of 2004 to February of 2007, 46 (36 pedicled and 10 free flaps) lower extremity flap reconstructions (10 fasciocutaneous, 34 musculocutaneous, and two adipofascial) were performed on 43 patients. Patient age ranged from 19 to 37 years. Time to reconstruction ranged from 7 to 82 days (average, 21 days). Seventy-six percent of all injuries were associated with an improvised explosive device blast. Mean number of prereconstructive washouts was five (range, two to 13). Fifty percent of all wounds cultured at admission revealed positive results, of which 57 percent were associated with Acinetobacter species. Total flap loss occurred in one flap and partial flap loss occurred in two flaps., Conclusion: Despite reconstruction in the subacute period, the high rate of antimicrobial colonization before wound closure, and the devastating nature of improvised explosive device blast injuries, early analysis of the National Naval Medical Center war extremity reconstruction cohort demonstrates low total and partial flap loss rates and acceptable infection rates.

The current indications for reduction mammoplasty include the relief of painful physical symptoms of macromastia. Numerous studies have demonstrated not only improvement in physical symptoms following reduction mammoplasty, but postoperative psychological benefits as well, including increased ability to participate in physical activity as a result of pain relief and decreased breast mass. Reduction mammoplasty may have additional effects on the patient's ability to breast-feed and perform breast self-exam. The present study is a retrospective study of the effects of reduction mammoplasty on breast-feeding, breast self-exam, physical symptoms, and physical activity. One-hundred and forty-one patients who underwent reduction mammoplasty at our institution between the years 1996-2005 agreed to participate in the study. Each was asked a series of questions in order to assess changes in symptoms and behaviors including breast-feeding and breast self-exam practices before and after the surgery. Patients were also asked questions regarding their pain symptoms and physical activity profiles. Ninety-seven percent of the participants claimed to have back, neck, and/or shoulder pain that was either significantly improved or completely resolved. Moreover, 100% of patients report that physical activity such as exercise was easier following reduction mammoplasty. Ninety-three percent of participants reported that performing breast self-exam following surgery was either the same (68%) or easier (25%) as a result of having less breast tissue. Eighty-nine percent of participants had no children following surgery, therefore effects on breast-feeding practices following reduction mammoplasty were not statistically significant. However, we suggest that when patients are seen in consultation or in the perioperative period, there is an opportunity to teach patients about the benefits of breast-feeding, and to assure patients that a pedicle flap reduction will likely allow breastfeeding. This is also a chance for physicians to teach patients how to perform breast self-examination and explain the importance of early breast mass detection.

Background: Implant infection is a common clinical complication of abdominal hernia repair. Our objectives were to determine if acellular dermal matrix (ADM) grafts resisted Staphylococcus aureus infection better (as measured by ability to reduce or clear bacterial counts) than synthetic (polytetrafluoroethylene [PTFE]) mesh when used in abdominal wall reconstruction, and to determine whether vascularization of the implant occurred. We hypothesized that the ability of the ADM grafts to vascularize and allow cellular ingrowth would allow the immune system to clear the infection better in these animals., Methods: In New Zealand White rabbits (average weight, 3.0 kg), a full-thickness 3 x 3 cm(2) abdominal defect was created, then repaired with an interpositional implant (ADM, n = 62; PTFE, n = 57). Before skin closure, the epidermal surface of each implant was inoculated with 1 mL of S. aureus at various concentrations (10(4) colony-forming units [CFU]/mL, n = 82; 10(6) CFU/mL, n = 27; 10(9) CFU/mL, n = 10), and the rabbits were harvested at either day 7 or day 21., Results: At day 7, ADM grafts inoculated with 10(4) CFU had lower counts or no bacteria (p = 0.006), fewer adhesions (p = 0.005), and fewer abscesses (p = 0.008) than PTFE grafts. By day 21, more ADM (n = 12) than PTFE (n = 0) grafts were free of bacteria (p = 0.002). Fewer rabbits with ADM grafts formed abscesses (13 vs. 19; p = 0.03). When evaluating the 7- and 21-day 10(4) CFU groups combined, a total of 15 rabbits with ADM cleared the bacteria completely vs. none of those with PTFE grafts (p < 0.001). There was no significant difference in bacterial counts or wound complications at days 7 or 21 between PTFE and ADM implants when inoculated with 10(6) CFU. All rabbits inoculated with 10(9) CFU died of sepsis within 48 h. Herniation did not occur in any of the animals., Conclusions: Our study demonstrates that ADM resists surgical site infection caused by S. aureus in an animal model without compromising the ventral hernia repair. This ability of ADM grafts to perform well in the setting of infection is most likely attributable to their capacity to vascularize and aid clearance of bacteria.

Background: Recent clinical trials involving patients with acute coronary syndromes have demonstrated significant reduction in the progression of coronary artery thrombosis using a regimen of aspirin, heparin, and the glycoprotein IIb/IIIa inhibitor tirofiban. Acute coronary syndromes and free tissue transfer are similar pathophysiologically in that they both involve endothelial injury, thrombosis, and ischemia. In this study, the authors investigate tirofiban, combined with aspirin and heparin, for the prevention of microsurgical anastomotic thrombosis in a thrombogenic rat model., Methods: Using a randomized, controlled, double-blind experimental design, 80 thrombogenic anastomoses were performed on rat femoral arteries (n = 40) and veins (n = 40). Preoperatively, each rat received one of four treatment regimens: aspirin and heparin (regimen 1), aspirin and heparin plus tirofiban (regimen 2), tirofiban alone (regimen 3), or isotonic saline (control) (regimen 4). Vessels were assessed for patency at 5, 15, 30, and 120 minutes after reperfusion and then harvested for microscopic analysis., Results: At 120 minutes after reperfusion, regimen 1 had an arterial and venous patency rate of 80 percent and 70 percent, respectively, whereas the vessel patency rate for regimen 2 was 100 percent. The difference between regimens 1 and 2 was not statistically significant. Regimens 3 and 4 had vessel patency rates of 40 percent or less. The aspirin/heparin and aspirin/heparin/tirofiban groups both demonstrated significantly improved vessel patency and significantly less thrombotic occlusion compared with controls., Conclusions: Combination therapy with aspirin, heparin, and tirofiban significantly increases arterial and venous patency and decreases anastomotic thrombus formation in thrombogenic anastomoses in rats. The role of glycoprotein IIb/IIIa inhibitors in microsurgery warrants further investigation.

Many human embryonic stem cell (hESC) lines have been reported, but only a few of them have been fully characterized. In this report, five new hESC lines were derived from 32 discarded blastocysts in Taiwan, and these lines were continuously cultured on mitotically inactivated mouse embryonic fibroblast (MEF) feeder layer in the hESC medium for more than 44 passages and underwent freezing/thawing processes. All five hESC lines expressed characteristic undifferentiated hESC markers, such as SSEA-4, TRA-1-81, alkaline phosphatase, TERT, and the transcription factors POU5F1 (OCT4) and NANOG. hESC lines T1 and T3 possess normal female karyotypes, whereas lines T4 and T5 are normal male, but line T2 is male trisomy 12 (47XY,+12). hESC lines T1, T2, T3, and T5 were able to produce teratomas in severe combined immunodeficient (SCID) mice, and line T4 could only form embryoid bodies (EBs) in vitro. Global gene expression profiles of these five newly derived hESC lines were analyzed using the Affymetrix human genome U133 plus 2.0 GeneChip. The results showed that 4,145 transcripts, including 19% of unknown functions, were detected in all five hESC lines. Comparison of the 4,145 genes commonly expressed in the five hESC lines with those genes expressed in teratomas produced by the hESC line T1 and placenta revealed 40 genes exclusively expressed in all five hESC lines. These 40 genes include the previously reported stemness genes, such as POU5F1 (OCT4), NANOG, TDGF1 (CRIPTO), SALL4, LECT1, and BUB1 responsible for self-renewal and pluripotent differentiation. The global gene expression analysis also indicated that the transforming growth factor-beta (TGF-beta)/activin branch components inhibin BC, ACVR2A, ACVR1 (ALK2), TGFBR1 (ALK5), and SMAD2 were found to be highly expressed in undifferentiated states of these five hESC lines and decreased upon differentiation. In short, the hESC nature of these five hESC lines is supported by the undifferentiated state, extensive renewal capacity, and pluripotency, including the ability to form teratomas and/or EBs. These cell lines will be useful for human embryonic stem cell biology and drug development.

The application of human embryonic stem (hES) cells in regenerative medicine will require rigorous quality control measures to ensure the safety of hES cell-derived grafts. During propagation in vitro, hES cells can acquire cytogenetic abnormalities as well as submicroscopic genetic lesions, such as small amplifications or deletions. Many of the genetic abnormalities that arise in hES cell cultures are also implicated in human cancer development. The causes of genetic instability of hES cells in culture are poorly understood, and commonly used cytogenetic methods for detection of abnormal cells are capable only of low-throughput analysis on small numbers of cells. The identification of biomarkers of genetic instability in hES cells would greatly facilitate the development of culture methods that preserve genomic integrity. Here we show that CD30, a member of the tumor necrosis factor receptor superfamily, is expressed on transformed but not normal hES cells, and that CD30 expression protects hES cells against apoptosis.

Background: The purpose of this study was to evaluate the effects of fondaparinux, a selective antithrombin III agonist, in comparison to the low-molecular-weight heparin enoxaparin in the survival of a congested skin flap., Materials and Methods: Eighteen axial-pattern auricular flaps were performed on rabbits using a well-described congested flap model. Animals were randomized into 2 treatment groups, enoxaparin (n = 6) and fondaparinux (n = 6), and a control group (n = 6) that received no treatment. Skin flap survival area was measured postoperatively at 7 and 14 days., Results: The groups that received fondaparinux and enoxaparin had similar mean flap survival areas and were not statistically different. However, both treatment groups significantly increased flap survival compared with controls (P < 0.014)., Conclusions: Fondaparinux, like enoxaparin, significantly improves survival of congested flaps in rabbits. Its use instead of enoxaparin may be warranted, given that it eliminates the risk of heparin-induced thrombocytopenia. Further study in humans is warranted.

Background: This cadaver study investigates the efficacy and safety of the Biomet knife and technique for percutaneous A1 pulley release. We also evaluate the anatomic relationship between specific palmar surface landmarks and relevant underlying structures and identify differences between genders., Methods: Eighty percutaneous A1 pulley releases, excluding the thumb, were performed on 20 fresh human cadaver hands (10 male, 10 female)., Results: Complete release was obtained in 60 of 80 fingers. Success rates for each surgeon improved markedly as the study progressed. There were no significant differences between males and females regarding the distance between a standardized incision site and the proximal edge of the A1 pulley., Conclusions: A learning curve exists for percutaneous A1 pulley release using the Biomet knife and technique. The extended distal palmar crease is a reasonable incision site for percutaneous release of the index, middle, and ring A1 pulleys in both men and women as the A1 pulley begins just distal to this surface landmark.