In situ reduction of chloroauric acid (HAuCl4) for generation of catalytic Au nanoparticle embedded triazine based covalent organic polymer networks

Covalent-organic polymer networks (COPNs) have been used as catalyst supports due to their stable and favorable structure. Herein, a simple synthetic route was applied to generate Au@COPN-1 hybrids via in situ reduction of gold ions with no additional reducing agent. Synthesized novel COPN-1 was mixed with different concentrations of HAuCl₄ which resulted in Au@COPN-1 with varying sizes of Au nanoparticles in a controlled manner. The microstructural and morphological features of COPN-1 and Au@COPN-1 were characterized in detail using FT-IR, C-NMR, elemental analysis, UV-Vis, XRD, TEM, BET, and TGA. It is noteworthy that the red-shifted LSPR peaks of Au nanoparticles produced with increasing concentrations of HAuCl₄ indicated an increase in the particle size of the Au nanoparticles as justified by TEM images. The optimum catalytic activity of Au@COPN-1 was obtained when 4.6 × 10⁻³ mM HAuCl₄ was used, which led to the complete reduction of 4-nitrophenol within 16 minutes with excellent recyclability for more than 5 catalytic cycles, giving yields over 94%. Moreover, the non-aggregation of nanoparticles in the reused catalyst further confirmed the stability of the prepared catalysts. Consequently, these results indicated that in situ synthesis of AuNPs inside the COPN-1 matrix produces a promising catalyst platform for the reduction of aromatic nitro compounds, for example, for the degradation of one of the most common persistent organic pollutants 4-nitrophenol, as shown here. In addition, the Au@COPN-1 hybrid system showed good biocompatibility at appropriate doses confirmed by a dynamic real-time cell analysis system which can be used in various medical applications, such as drug delivery, in the future.

A facile synthetic route was applied to generate Au@COPN-1 hybrids via in situ reduction of Au³⁺ with no additional reducing agent. Au@COPN-1 is a promising catalyst platform and good biocompatibility confirmed by dynamic real-time cell analysis.     

Investigation of Dynamic Thiol/Disulfide Homeostasis and Nitrosative Stress in Patients with Wilson Disease

Background: Wilson disease (WD) is an autosomal recessive inherited disorder of copper (Cu²⁺) metabolism, resulting in Cu²⁺ accumulation and liver and central nervous system toxicity. Oxidative stress may have a role in the pathogenesis of Wilson disease, but the roles of thiol/disulfide homeostasis and nitrosative stress have not been examined. The purpose of this study was to evaluate whether there is a modification in thiol/disulfide homeostasis and nitrosative stress in patients with Wilson disease.Methods: A total of 50 patients with Wilson disease (42 under drug treatment and 8 newly diagnosed patients with no drug treatment) and 50 healthy gender- and age-matched controls were enrolled for this study. Serum native thiol and total thiol levels were measured with a spectrophotometric method. The number of disulfide bonds and the related ratios were determined from these measurements. Serum nitric oxide (NO) and 3-nitrotyrosine (3-NT) levels were analyzed using chemiluminescence and ELISA assays, respectively.Results: The average native thiol levels of the patient group under drug treatment were found to be markedly higher than the levels of controls (P < .05). We detected no marked changes in total thiol and disulfide levels, and disulfide/total thiol, disulfide/native thiol, or native thiol/total thiol ratios between groups. We found significant elevations in NO levels in Wilson disease group before drug treatment, and the 3-NT levels in the Wilson disease groups prior to (P < .05) and under drug treatment (P < .01), when compared to controls.Conclusion: Our data are the first to show that nitrosative stress and thiol/disulfide homeostasis can contribute to the pathogenesis of Wilson disease.     

Treatment of three hereditary leiomyomatosis patients with cryotherapy

Hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome is an autosomal dominant disorder characterized by cutaneous leiomyomas (CLM), uterine leiomyomas, and the increased risk of renal cell carcinoma. Piloleiomyomas develop from the arrectorpili muscle and are usually painful. For 22% of the affected patients, the pain is reported to impair their life quality. Since there are few case reports about cryotherapy for cutaneous leiomyomas in the literature, we have decided to present three patients who had painful cutaneous leiomyomas treated with cryotherapy.     

The Investigation of Genotype-Phenotype Relationship in Multiple Primary Malignant Neoplasia Patients

Multiple primary malignant neoplasms (MPMN) are rare tumors that have attracted attention with increasing incidence rates in recent years and where cancer susceptibility genes may play a role in their etiology. In this study, it was aimed to determine the genotype-phenotype correlation in patients with MPMN. From January 2018 to January 2020, thirty patients were analyzed for 59 cancer susceptibility genes and diagnosed with MPMN, using a large multigene panel with Next Generation Sequencing technique (NGS) in Turkey. The mean age of first and second cancer diagnosis of cases were calculated as 42.5 and 49.9 (respectively). These primary cancers were frequently detected in the colon and breast, and the interval between diagnosis was 89 months. In 9 of the patients (30%); BRCA2, MSH6, MLH1, MUTYH, and ATM were detected as causal genes. Relatives with cancer of MPMN patients with causative gene carriers were detected in higher numbers than non-carrier. According to the logistic regression model applied, patients with at least 1 relatives with cancer were found to have a 0.38-fold increased risk of being a causal gene variant carrier. Hereditary cancer susceptibility genes may play an important role in the etiology of MPMN. In MPMN cases, detection of the causal gene by genetic analysis; It will enable not only to ensure a complete and accurate diagnosis of the sick individual and to plan the treatment properly, but also to include the carriers’ relatives in the intensive cancer screening, monitoring, and prevention program.     

A Systematic Characterization Approach for Vacuum Bag Only Prepregs towards an Accurate Process Design

Aerospace-grade composite parts can be manufactured using Vacuum Bag Only prepregs through an accurate process design. Quality in the desired part can be realized by following process modeling, process optimization, and validation, which strongly depend on a primary and systematic material characterization methodology of the prepreg system and material constitutive behavior. The present study introduces a systematic characterization approach of a Vacuum Bag Only prepreg by covering the relevant material properties in an integrated manner with the process mechanisms of fluid flow, consolidation, and heat transfer. The characterization recipe is practiced under the categories of (i) resin system, (ii) fiber architecture, and (iii) thermal behavior. First, empirical models are successively developed for the cure-kinetics, glass transition temperature, and viscosity for the resin system. Then, the fiber architecture of the uncured prepreg system is identified with X-ray tomography to obtain the air permeability. Finally, the thermal characteristics of the prepreg and its constituents are experimentally characterized by adopting a novel specimen preparation technique for the specific heat capacity and thermal conductivity. Thus, this systematic approach is designed to provide the material data to process modeling with the motivation of a robust and integrated Vacuum Bag Only process design.     

Contribution of diffusion‐weighted imaging to dynamic contrast‐enhanced MRI in the characterization of papillary breast lesions

Papillary lesions have a broad spectrum of appearances on magnetic resonance imaging (MRI ). The purpose of this study was to evaluate whether apparent diffusion coefficient (ADC ) values of papillary lesions can be used to characterize lesion as benign or malignant. This retrospective study included 29 papillary lesions. Diagnostic values of dynamic contrast‐enhanced MRI (DCE‐MRI), DWI ‐ADC , and DCE ‐MRI plus DWI ‐ADC were separately calculated. The malignant papillary lesions (0.744×10^?3 mm²/s) exhibited significantly lower mean ADC values than the benign lesions (1.339×10^?3 mm²/s). Addition of DWI to standard DCE ‐MRI provided 100% sensitivity. We hypothesized that this combination may prevent unnecessary excisional biopsies.     

TSHRV656F Activating Variant of the Thyroid Stimulating Hormone Receptor Gene in Neonatal Onset Hyperthyroidism: A Case Review

An activating variant of the thyroid stimulating hormone receptor (TSHR) gene is one of the rare causes of neonatal hyperthyroidism. This disorder may occur as a result of an autosomal dominant inheritance or sporadically through de novo variation. Here we present a case of neonatal onset congenital non-autoimmune hyperthyroidism (NAH) with a sporadic germline activating TSHRV656F variant. A female infant with tachycardia, who was transferred due to hyperthyroidism in the first week of life, displayed no other symptoms or signs. The patient’s mother did not have Graves’ disease, and TSHR stimulating antibodies were not present in the mother or baby. Imaging showed thyroid gland hyperplasia and left ventricular hypertrophy, the patient was subsequently put on methimazole treatment. After six months undergoing treatment, a heterozygous p.Val656Phe (V656F) (c.1966G>T) variant was detected on exon 10 of the TSHR gene. The variant was not identified in the mother and father, so the case was assumed to be sporadic. In conclusion, although the literature describes V656F variant as a somatic variant in children and adults with toxic thyroid nodule(s) that results in the structural activation of the TSH receptor, no previous cases of neonatal hyperthyroidism due to TSHRV656F variant have been reported. This study is the first case review that highlights the relationship between TSHRV656F variant and neonatal onset NAH.