Extrusion, electrospinning, and microdrawing are widely used to create fibrous polymer mats, but these approaches offer limited access to oriented arrays of nanometer-scale fibers with controlled ...size, shape, and lateral organization. We show that chemical vapor polymerization can be performed on surfaces coated with thin films of liquid crystals to synthesize organized assemblies of end-attached polymer nanofibers. The process uses low concentrations of radical monomers formed initially in the vapor phase and then diffused into the liquid-crystal template. This minimizes monomer-induced changes to the liquid-crystal phase and enables access to nanofiber arrays with complex yet precisely defined structures and compositions. The nanofiber arrays permit tailoring of a wide range of functional properties, including adhesion that depends on nanofiber chirality.
The number of patients with diabetes is increasing particularly in Asia-Pacific region. Many of them are treated with antidiabetics. As the basis of the studies on the benefit and harm of ...antidiabetic drugs in the region, the information on patterns of market penetration of new classes of antidiabetic medications is important in providing context for subsequent research and analyzing and interpreting results.
We compared penetration patterns of dipeptidyl peptidase-4 (DPP-4) inhibitors in Taiwan, Hong Kong, Japan, and the United States. We used the Taiwan National Health Insurance Research Database, a random sample of the Hong Kong Clinical Data Analysis and Reporting System, the Japan Medical Data Center database, and a 5% random sample of the US Medicare database converted to the Observational Medical Outcomes Partnership's Common Data Model to identify new users of oral antidiabetic medications. We standardized prevalence and incidence rates of medication use by age and sex to those in the 2010 Taiwanese population. We compared age, sex, comorbid conditions, and concurrent medications between new users of DPP-4 inhibitors and biguanides.
Use of DPP-4 inhibitors 1 year after market entry was highest in Japan and lowest in Hong Kong. New users had more heart failure, hyperlipidemia, and renal failure than biguanide users in Taiwan, Hong Kong, and the United States while the proportions were similar in Japan. In a country with low penetration of DPP-4 inhibitors (eg, Hong Kong), users had diabetes with multiple comorbid conditions compared with biguanidine users. In a country with high penetration (eg, Japan), the proportion of users with comorbid conditions was similar to that of biguanide users.
We observed a marked difference of the penetration patterns of newly marketed antidiabetics in different countries in Asia. Those results will provide the basic information useful in the future studies.
Cyclooxygenase-2 (COX-2) expression is induced by mitogenic and proinflammatory factors. Its overexpression plays a causal role in inflammation and tumorigenesis. COX-2 expression is tightly ...regulated, but the mechanisms are largely unclear. Here we show the control of COX-2 expression by an endogenous tryptophan metabolite, 5-methoxytryptophan (5-MTP). By using comparative metabolomic analysis and enzyme-immunoassay, our results reveal that normal fibroblasts produce and release 5-MTP into the extracellular milieu whereas A549 and other cancer cells were defective in 5-MTP production. 5-MTP was synthesized from l -tryptophan via tryptophan hydroxylase-1 and hydroxyindole O-methyltransferase. 5-MTP blocked cancer cell COX-2 overexpression and suppressed A549 migration and invasion. Furthermore, i.p. infusion of 5-MTP reduced tumor growth and cancer metastasis in a murine xenograft tumor model. We conclude that 5-MTP synthesis represents a mechanism for endogenous control of COX-2 overexpression and is a valuable lead for new anti-cancer and anti-inflammatory drug development.
Molecules can be immobilized onto biomaterials by a chemical vapor deposition (CVD) coating strategy. Pentafluorophenolester groups react with amine side chains on antibodies, which can selectively ...immobilize adenoviral vectors for gene delivery of growth factors. These vectors can produce functional proteins within defined regions of biomaterials to produce customizable structures for targeted tissue regeneration.
Previous studies report an association between maternal diabetes mellitus (MDM) and attention-deficit/hyperactivity disorder (ADHD), often overlooking unmeasured confounders such as shared genetics ...and environmental factors. We therefore conducted a multinational cohort study with linked mother-child pairs data in Hong Kong, New Zealand, Taiwan, Finland, Iceland, Norway and Sweden to evaluate associations between different MDM (any MDM, gestational diabetes mellitus (GDM) and pregestational diabetes mellitus (PGDM)) and ADHD using Cox proportional hazards regression. We included over 3.6 million mother-child pairs between 2001 and 2014 with follow-up until 2020. Children who were born to mothers with any type of diabetes during pregnancy had a higher risk of ADHD than unexposed children (pooled hazard ratio (HR) = 1.16, 95% confidence interval (CI) = 1.08-1.24). Higher risks of ADHD were also observed for both GDM (pooled HR = 1.10, 95% CI = 1.04-1.17) and PGDM (pooled HR = 1.39, 95% CI = 1.25-1.55). However, siblings with discordant exposure to GDM in pregnancy had similar risks of ADHD (pooled HR = 1.05, 95% CI = 0.94-1.17), suggesting potential confounding by unmeasured, shared familial factors. Our findings indicate that there is a small-to-moderate association between MDM and ADHD, whereas the association between GDM and ADHD is unlikely to be causal. This finding contrast with previous studies, which reported substantially higher risk estimates, and underscores the need to reevaluate the precise roles of hyperglycemia and genetic factors in the relationship between MDM and ADHD.
Severe acute respiratory syndrome coronavirus 2 did not replicate efficiently in 13 bat cell lines, whereas severe acute respiratory syndrome coronavirus replicated efficiently in kidney cells of its ...ancestral host, the Rhinolophus sinicus bat, suggesting different evolutionary origins. Structural modeling showed that RBD/RsACE2 binding may contribute to the differential cellular tropism.
Purpose
To investigate the association between use of methylphenidate and risk of myocardial infarction among Asians.
Methods
We conducted a multinational self‐controlled case series study using ...nationwide healthcare databases of South Korea (2002–2018), Taiwan (2004–2015), and Hong Kong (2001–2016). Of patients with myocardial infarction who were also prescribed methylphenidate within the observation period, methylphenidate use was classified into four mutually exclusive periods by each person‐day: exposed (exposed to methylphenidate), pre‐exposure (prior to the first methylphenidate prescription), washout (after the end of methylphenidate treatment), and baseline (unexposed to methylphenidate). Risk of myocardial infarction among the three periods of methylphenidate use was compared to the baseline period using conditional Poisson regression analysis to estimate incidence rate ratios (IRRs) with 95% confidence intervals (CIs).
Results
We identified 2104, 484, and 30 patients from South Korea, Taiwan, and Hong Kong, respectively. Risk of myocardial infarction was the highest during the pre‐exposure period in all three populations: South Korea, pre‐exposure (IRR 3.17, 95% CI 3.04–3.32), exposed (1.05, 1.00–1.11), washout (1.92, 1.80–2.04); Taiwan, pre‐exposure (1.97, 1.78–2.17), exposed (0.72, 0.65–0.80), washout (0.56, 0.46–0.68); Hong Kong, pre‐exposure (18.09, 8.19–39.96), exposed (9.32, 3.44–25.28), washout (7.69, 1.72–34.41). Following stratification for age and sex, the trends remained analogous to the main findings across all three populations.
Conclusions
Although a positive association between initiating methylphenidate and the onset of myocardial infarction was observed, the risk was the highest in the period before its initiation. Thus, this multinational study suggests there was no causal relationship between methylphenidate and myocardial infarction among Asians.
Polymers prepared by chemical vapor deposition (CVD) polymerization have found broad acceptance in research and industrial applications. However, their intrinsic lack of degradability has limited ...wider applicability in many areas, such as biomedical devices or regenerative medicine. Herein, we demonstrate, for the first time, a backbone‐degradable polymer directly synthesized via CVD. The CVD co‐polymerization of 2.2para‐cyclophanes with cyclic ketene acetals, specifically 5,6‐benzo‐2‐methylene‐1,3‐dioxepane (BMDO), results in well‐defined, hydrolytically degradable polymers, as confirmed by FTIR spectroscopy and ellipsometry. The degradation kinetics are dependent on the ratio of ketene acetals to 2.2para‐cyclophanes as well as the hydrophobicity of the films. These coatings address an unmet need in the biomedical polymer field, as they provide access to a wide range of reactive polymer coatings that combine interfacial multifunctionality with degradability.
Breaking back: A new class of backbone‐degradable polymer coatings was developed via chemical vapor deposition co‐polymerization. These polymer coatings address a significant unmet need in the biomedical polymer field, as they provide access to a wide range of reactive polymer coatings that combine interfacial multifunctionality with degradability.
It is known that younger patients treated with antipsychotics are at increased risk of metabolic events; however, it is unknown how this risk varies according to ethnicity, the class of antipsychotic ...and the specific product used, and by age group. We conducted a multinational sequence symmetry study in Asian populations (Hong Kong, Japan, Korea, Taiwan and Thailand) and non-Asian populations (Australia and Denmark) to evaluate the metabolic events associated with antipsychotics in both Asian and non-Asian populations, for typical and atypical antipsychotics, and by the subgroups of children and adolescents, and young adults. Patients aged 6–30 years newly initiating oral antipsychotic drugs were included. We defined a composite outcome for metabolic events which included dyslipidemia, hypertension and hyperglycemia. We calculated the sequence ratio (SR) by dividing the number of people for whom a medicine for one of the outcome events was initiated within a 12-month period after antipsychotic initiation by the number before antipsychotic initiation. This study included 346,904 antipsychotic initiators across seven countries. Antipsychotic use was associated with an increased risk of composite metabolic events with a pooled adjusted SR (ASR) of 1.22 (95% CI 1.00–1.50). Pooled ASRs were similar between Asian (ASR, 1.22; 95% CI 0.88–1.70) and non-Asian populations (ASR, 1.22; 95% CI 1.04–1.43). The pooled ASR for typical and atypical antipsychotics was 0.98 (95% CI 0.85–1.12) and 1.24 (95% CI 0.97–1.59), respectively. No difference was observed in the relative effect in children and adolescents compared to young adults. The risk of metabolic events associated with antipsychotics use was similar in magnitude in Asian and non-Asian populations despite the marked difference in drug utilization patterns.
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