The 3D printed bulk samples fabricated by selective laser melting (SLM) of the additive manufacturing technique are usually considered to be 3D isotropic in microstructures and mechanical responses. ...This study systematically investigates the anisotropic responses in terms of hardness and electrochemical resistance for the X-, Y- and Z-planes of the SLM Ti-6Al-4V bulk samples fabricated with the zigzag laser path strategy. Results show that all SLM planes exhibit no significant difference in Young's modulus compared to the mechanically rolled plate. However, the X-plane, referred to the cross-sectional plane perpendicular to the laser moving direction, is found ~20% lower hardness and the lowest corrosion resistance compared to the Y- and Z-planes. The underlying reasoning is researched and discussed. The microstructure observations indicate that artifact holes are induced in the X-plane due to un-uniform laser intensity distribution between two neighboring printing lines. Alternatively, the Y- and Z-planes exhibit dense morphology due to multiple heating while zigzag scanning. Experimental results also indicate that the SLM materials exhibit higher corrosion resistance than the commercial rolled materials.
An ideal material has yet to be discovered that can completely treat dentin hypersensitivity; however, calcium phosphate precipitation has exhibited potential value for the treatment of dentin ...hypersensitivity by the occlusion of dentinal tubules. We hypothesized that a novel mesoporous silica biomaterial (nano CaO@mesoporous silica, NCMS) containing nano-sized calcium oxide particles mixed with 30% phosphoric acid can efficiently occlude dentinal tubules and significantly reduce dentin permeability, even with the presence of pulpal pressure. This highly supersaturated Ca2+-and HPO4
2−ion-containing NCMS paste was brushed onto dentin surfaces, and the ions diffused deeply into the dentinal tubules and formed a CaHPO4·2H2O precipitation with a depth of 100 μm. The results of the dentin permeability tests showed that the novel mesoporous material exhibited a significant reduction in dentin permeability (p < 0.05), even under simulated pulpal pressure, as compared with our previously developed material, DP-bioglass, and a commercial desensitizing material, Seal & Protect®.
Infection by hepatitis B virus (HBV) accounts for 50-80% of hepatocellular carcinoma (HCC) development worldwide, in which the HBV-encoded X protein (HBx) has critical role in the induction of ...carcinogenesis. Several studies have shown that thyroid hormone (TH) suppresses HCC development and protects hepatocytes from HBx-induced damage, thus it is of interest to examine whether TH can protect hepatocytes from HBx-induced carcinogenesis. By treating HBx- transgenic mice with or without TH, we confirmed the protective effects of TH on HBx-induced hepatocarcinogenesis, which was achieved via reduction of reactive oxygen species (ROS) inflicted DNA damage. We further found that TH induced biogenesis of mitochondria (MITO) and autophagy of HBx-targeted MITO simultaneously, consequently leading to suppression of HBx-promoted ROS and carcinogenesis. Using microarray data analysis, this protective effect of TH was found to be mediated via activation of PTEN-induced kinase 1 (PINK1) in hepatocytes. PINK1, in turn, activated and recruited Parkin, an E3 ligase, to ubiquitinate MITO-associated HBx protein and trigger selective mitophagy. The pathological significance of the TH/PINK1 pathway in liver protection was confirmed by the concomitant decrease in expression of both TR and PINK1 in matched HCC tumor tissues and negatively correlated with aggressive progression of cancer and poor prognosis. Our data indicate that TH/PINK1/Parkin pathway has a critical role in protecting hepatocytes from HBx-induced carcinogenesis. Notably, several liver-targeting therapeutic derivatives of TH facilitating prevention or therapy of steatosis have been identified. Furthermore, our proof-of-concept experiments suggest that application of T
constitutes an effective novel therapeutic or preventive option for HCC. Thus, the utilization of the agonists of TRs could be the meaningful strategy in liver relative diseases, ranging from simple hepatic steatosis to HCC.
Metabolic syndrome (MS) was conceptualized to identify people at risk for cardiovascular disease and type 2 diabetes; however, the epidemiology of MS and its combinations of components in older ...adults remains unclear. Data from the Senior Health Examination Program of the New Taipei City Government in Taiwan in 2014 were obtained for this study. All participants aged 65 years or older and those with a prior history of cardiovascular disease, cerebrovascular disease, or diabetes mellitus were excluded. 29,164 senior citizens were retrieved for this study, and 12,331 (41.28%) of the participants were male. Female participants were more likely to have MS (42.7% vs.31.3%, p <0.001). Female participants with MS were older than those without MS (73.15±6.5 vs. 72.10±6.14 years, p <0.001). Conversely, male participants with MS were younger than those without MS (72.93±6.70 vs. 73.52±6.98 years, p <0.001). The most common combination of MS components was the triad of high blood glucose, high blood pressure and central obesity (25.2% of all participants with MS). Age-related changes in MS component combinations were noted only when central obesity was present. The strongest MS component combination for new-onset diabetes mellitus was high blood glucose, hypertriglyceridemia, reduced HDL-C and central obesity (HR: 5.42, P<0.001). In conclusion, not all component combinations of MS were of the same prognostic impact or the risk for new-onset diabetes mellitus. Further study is needed to develop individualized intervention programs for MS based on risk profiles of older adults is needed.
The open-cell porous Ti-6Al-4V structure, intended to be applied as replacement for human cortical and cancellous bone, are fabricated by selective laser melting (SLM). The computer aided design ...(CAD) was used to design porous structures in various porosity levels from 40% to 80% and with pore sizes from 600 to 1000 μm, in order to fit the bone-tissue in-growth. The SLM porous samples with 40% to 70% porosity matched well with the CAD structure, but the 80% porosity one was found to be difficult to achieve the design. In comparison with the CAD structures and the SLM samples, there are minor discrepancies in terms of pore size and ligament width, mainly a result of laser beam broadening. To achieve more precise SLM porous morphologies, further reduction of powder size and laser beam diameter would be necessary. The measured data on the Young's modulus and yield strength of the SLM porous samples can be roughly estimated by the Gibson and Ashby model. The sample with 67% porosity was found to match best with human bone, with Young's modulus of 15 GPa and yield stress of 129 MPa, preventing from the risk of stress shielding effect.
•The porous Ti-6Al-4V foams are prepared by selective laser melting.•Minor discrepancies between CAD and SLM are due to laser beam broadening.•The 67% porosity sample matches with human bone avoiding stress shielding effect.
Inflammatory markers such as interleukin (IL)-6 and tumour necrosis factor-alpha (TNF-α) are elevated in dialysis patients and can predict cardiovascular events and all-cause mortality. Endotoxin is ...an important source and also another marker of inflammation in patients with chronic kidney disease. The aim of this study was to evaluate the impact of oral probiotics on serum levels of endotoxemia and cytokines in peritoneal dialysis (PD) patients. The decline of residual renal function, peritonitis episodes, and cardiovascular events were also recorded. From July 2011 to June 2012, a randomised, double-blind, placebo-controlled trial was conducted in PD patients. The intervention group received one capsule of probiotics containing 10(9) cfu Bifobacterium bifidum A218, 10(9) cfu Bifidobacterium catenulatum A302, 10(9) cfu Bifidobacterium longum A101, and 10(9) cfu Lactobacillus plantarum A87 daily for six months, while the placebo group received similar capsules containing maltodextrin for the same duration. Levels of serum TNF-α, interferon gamma, IL-5, IL-6, IL-10, IL-17, and endotoxin were measured before and six months after intervention. 39 patients completed the study (21 in the probiotics group and 18 in the placebo group). In patients receiving probiotics, levels of serum TNF-α, IL-5, IL-6, and endotoxin significantly decreased after six months of treatment, while levels of serum IL-10 significantly increased. In contrast, there were no significant changes in levels of serum cytokines and endotoxin in the placebo group after six months. In addition, the residual renal function was preserved in patients receiving probiotics. In conclusion, probiotics could significantly reduce the serum levels of endotoxin, pro-inflammatory cytokines (TNF-α and IL-6), IL-5, increase the serum levels of anti-inflammatory cytokine (IL-10), and preserve residual renal function in PD patients.
Background and purpose
Restless legs syndrome (RLS) is an underestimated movement disorder in patients with end‐stage renal disease (ESRD). Several clinical and laboratory factors were inconsistently ...reported to associate with RLS. We aim to perform a large‐scale multicenter study to investigate the possible associated risk factors of RLS in patients with ESRD in Taiwan, a country with the highest incidence of uremia in the world.
Methods
From October 2009 to October 2011, we constitutively recruited 1130 patients with ESRD from 17 hemodialysis centers. Demographic, laboratory data, presence and severity of RLS were collected. Odds ratios (ORs) were estimated by logistic regression models.
Results
We found the prevalence of RLS to be 25.3% in patients with ESRD. Having type 2 diabetes OR = 3.61 (2.27–5.77), P < 0.01, low serum transferrin saturation OR = 1.42 (1.01–2.03), P < 0.05 and duration of dialysis OR = 1.09 (1.03–1.14), P < 0.01 were associated with RLS. In contrast, high serum hemoglobin level was inversely associated with RLS OR = 0.61 (0.40–0.89), P < 0.05. RLS has a significant impact on sleep quality in dialysis patients. Among patients with RLS, history of type 2 diabetes OR = 4.04 (1.65–10.79), P < 0.05, low serum hemoglobin level OR = 5.41 (2.43–13.12), P < 0.01 and duration of dialysis OR = 1.01 (1.01–1.02), P < 0.01 were associated with increased severity of RLS.
Conclusions
Our findings demonstrated that RLS is common in Taiwanese dialysis patients. Clinicians should have a high suspicion for the presence of RLS symptoms in patients with ESRD, especially those with type 2 diabetes, anemia, low serum iron status and long duration of dialysis.
Summary
Bone mineral density (BMD) may be increased due to vertebral compression fractures (VCF). Our study showed trabecular bone scores (TBS) was less affected than BMD by fractured vertebrae. The ...TBS of most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity, could still be used in predicting fracture risk.
Introduction
Trabecular bone score (TBS), a noninvasive tool estimating bone microarchitecture, provides complementary information to lumbar spine bone mineral density (BMD). Lumbar spine BMD might be increased due to both degenerative disease and vertebral compression fractures (VCF). Lumbar spine TBS has been confirmed not influenced by osteoarthrosis, but the effects of VCF are still not been well evaluated. This study aimed to investigate whether lumbar spine TBS was affected by fractured vertebrae.
Methods
We studied postmenopausal women and men above 50 years old who underwent DXA between January 1, 2017, and May 31, 2019. By calculating the difference of BMD and TBS between L1 and the mean of L2-3, the study compared the difference of values between the control group and fracture group to determine the effects of fractured vertebrae on BMD and TBS.
Results
A total of 377 participants were enrolled with 202 in the control group (157 females; age: 68.06 ± 6.47 years) and 175 in the fracture group (147 females; age: 71.71 ± 9.44 years). The mean BMD of the L1 vertebrae in the fracture group was significantly higher than that in the control group (
p
< 0.0001). There was no significant difference between the mean differences of TBS between L1 and the means of L2-3 vertebrae in the control group and the most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity.
Conclusion
Lumbar spine TBS, unlike BMD, is less affected by fractured vertebrae. The TBS of most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity, could still be used in predicting fracture risk.
Objective
To determine whether maternal multiple sclerosis (MS) is associated with increased risk of adverse pregnancy outcomes in an East Asian country by using a nationwide population-based ...dataset.
Method
This study linked two nationwide population-based datasets, the birth certificate registry and the Taiwan National Health Insurance Research Dataset. We identified a total of 174 women who gave birth from 2001 to 2003, who were diagnosed with MS within the 2 years preceding the index deliveries, together with 1,392 matched women without chronic disease as a comparison cohort. Multivariate logistic regression analyses were performed for estimation.
Results
We found that compared with healthy mothers, MS was independently associated with a 2.25-fold risk of preterm birth (95% CI = 1.37–3.70) and a 1.89-fold (95% CI = 1.30–2.76) higher risk of babies small for gestational age, after adjusting for family income and maternal, paternal, and infant characteristics. Mothers with MS were also more likely to have cesarean deliveries.
Conclusion
Our study documents increased the risk of adverse pregnancy outcomes for mothers with MS, highlighting a need for more intensive monitoring and obstetric care during pregnancy. Future studies should explore the distinct manifestations and mechanisms of MS in diverse ethnic groups, so more complete information can be provided to affected women concerning pregnancy.
Airborne disease transmission has always been a topic of wide interests in various fields for decades. Cough is found to be one of the prime sources of airborne diseases as it has high velocity and ...large quantity of droplets. To understand and characterize the flow dynamics of a cough can help to control the airborne disease transmission. This study has measured flow dynamics of coughs with human subjects. The flow rate variation of a cough with time can be represented as a combination of gamma‐probability‐distribution functions. The variables needed to define the gamma‐probability‐distribution functions can be represented by some medical parameters. A robust multiple linear regression analysis indicated that these medical parameters can be obtained from the physiological details of a person. However, the jet direction and mouth opening area during a cough seemed not related to the physiological parameters of the human subjects. Combining the flow characteristics reported in this study with appropriate virus and droplet distribution information, the infectious source strength by coughing can be evaluated.
Practical Implications
There is a clear need for the scientific community to accurately predict and control the transmission of airborne diseases. Transportation of airborne viruses is often predicted using Computational Fluid Dynamics (CFD) simulations. CFD simulations are inexpensive but need accurate source boundary conditions for the precise prediction of disease transmission. Cough is found to be the prime source for generating infectious viruses. The present study was designed to develop an accurate source model to define thermo‐fluid boundary conditions for a cough. The model can aid in accurately predicting the disease transmission in various indoor environments, such as aircraft cabins, office spaces and hospitals.
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