l-2-Hydroxyglutarate contributes to tumor radioresistance through regulating the hypoxia-inducible factor-1α signaling pathway.

l-2-Hydroxyglutarate (l-2-HG) has been regarded as a tumor metabolite, and it plays a crucial role in adaptation of tumor cells to hypoxic conditions. However, the role of l-2-HG in tumor radioresistance and the underlying mechanism have not yet been revealed. Here, we found that l-2-HG exhibited to have radioresistance effect on U87 human glioblastoma cells, which could reduce DNA damage and apoptosis caused by irradiation, promote cell proliferation and migration, and impair G2/M phase arrest. Mechanistically, l-2-HG upregulated the protein level of hypoxia-inducible factor-1α (HIF-1α) and the expression levels of HIF-1α downstream target genes. The knockdown of l-2-hydroxyglutarate dehydrogenase (L2HGDH) gene promoted the tumor growth and proliferation of U87 cells in nude mice by increasing HIF-1α expression level in vivo. In addition, the low expression level of L2HGDH gene was correlated with the short survival of patients with glioma or kidney cancer. In conclusion, our study revealed the role and mechanism of l-2-HG in tumor radioresistance and may provide a new perspective for overcoming tumor radioresistance and broaden our comprehension of the role of metabolites in tumor microenvironment.

Triptolide exposure triggers testicular vacuolization injury by disrupting the Sertoli cell junction and cytoskeletal organization via the AKT/mTOR signaling pathway.

BACKGROUND: Despite the known reproductive toxicity induced by triptolide (TP) exposure, the regulatory mechanism underlying testicular vacuolization injury caused by TP remains largely obscure. METHODS: Male mice were subjected to TP at doses of 15, 30, and 60 µg/kg for 35 consecutive days. Primary Sertoli cells were isolated from 20-day-old rat testes and exposed to TP at concentrations of 0, 40, 80, 160, 320, and 640 nM. A Biotin tracer assay was conducted to assess the integrity of the blood-testis barrier (BTB). Transepithelial electrical resistance (TER) assays were employed to investigate BTB function in primary Sertoli cells. Histological structures of the testes and epididymides were stained with hematoxylin and eosin (H&E). The expression and localization of relevant proteins or pathways were assessed through Western blotting or immunofluorescence staining. RESULTS: TP exposure led to dose-dependent testicular injuries, characterized by a decreased organ coefficient, reduced sperm concentration, and the formation of vacuolization damage. Furthermore, TP exposure disrupted BTB integrity by reducing the expression levels of tight junction (TJ) proteins in the testes without affecting basal ectoplasmic specialization (basal ES) proteins. Through the TER assay, we identified that a TP concentration of 160 nM was optimal for elucidating BTB function in primary Sertoli cells, correlating with reductions in TJ protein expression. Moreover, TP exposure induced changes in the distribution of the BTB and cytoskeleton-associated proteins in primary Sertoli cells. By activating the AKT/mTOR signaling pathway, TP exposure disturbed the balance between mTORC1 and mTORC2, ultimately compromising BTB integrity in Sertoli cells. CONCLUSION: This investigation sheds light on the impacts of TP exposure on testes, elucidating the mechanism by which TP exposure leads to testicular vacuolization injury and offering valuable insights into comprehending the toxic effects of TP exposure on testes.

Genetic risk, muscle strength and risk of incident major depressive disorder: results from the UK Biobank.

BACKGROUND: Genetic factors and muscle strength both contribute to the risk of major depressive disorder (MDD), but whether high muscle strength can offset the risk of MDD with different genetic risk is unknown. This study aims to examine whether a higher muscle strength is associated with lower risk of MDD regardless of genetic risk among middle-aged and older adults. METHODS: This cohort study obtained data from the UK Biobank, which includes 345,621 individuals aged 40-69 years (mean (standard deviation): 56.7 (7.99) years) without baseline MDD. Polygenic risk score for MDD was categorised as low, intermediate or high. The mean of the right- and left-hand grip strength values was used in the analysis and was divided into three categories. RESULTS: 9,753 individuals developed MDD within 2,752,461 person-years of follow-up. The multivariable adjusted hazard ratios (HRs) (95% confidence intervals (CIs)) of MDD across increased grip strength categories were 1.00, 0.72 (0.68-0.75) and 0.56 (0.53-0.59) (P for trend <0.0001). The HRs (95% CIs) of incident MDD across the genetic risk categories were 1.00, 1.11 (1.05-1.17) and 1.20 (1.13-1.28) (P for trend <0.0001); 4.07% of individuals with a high genetic risk and low grip strength developed MDD, and 1.72% of individuals with a low genetic risk and high grip strength developed MDD, with an HR (95% CI) of 0.44 (0.39-0.50). CONCLUSIONS: Both muscle strength and genetic risk were significantly associated with incident MDD. A higher muscle strength was associated with a lower MDD risk among individuals with a high genetic risk. Improving muscle strength should be encouraged for all individuals, including individuals with high genetic risk for MDD.

High precision angular displacement measurement based on self-correcting error compensation of three image sensors.

As the feedback link of a numerical control system, the measurement accuracy of absolute angular displacement measurements directly affects the control performance of a numerical control system. In previous research, angular displacement measurements based on dual image sensors can achieve higher measurement performance. However, the elimination of harmonic error by the dual image sensor is still limited. For this reason, this paper proposes an image-type angular displacement measurement method based on self-correction error compensation of three image sensors. First, the mathematical model of harmonic error is established, and the shortcomings of using dual image sensors to compensate the error are analyzed. Then, a high precision angular displacement measurement method based on three image sensors is proposed. Finally, the self-correction error compensation method of three image sensors is applied to the angular displacement measurement system, and the measurement performance is verified. The experimental results show that a measurement accuracy of 1.76'' can be achieved on the circular grating with a diameter of 96 mm. In contrast, the dual image sensor can only achieve a measurement accuracy of 2.88''. It is concluded that the odd number of image sensors can achieve higher measurement accuracy than the even number. This research lays a foundation for the realization of high precision image angular displacement measurement.

High-precision displacement measurement algorithm based on a depth fusion of grating projection pattern.

Displacement measurement based on an image recognition algorithm has more advantages in the field of displacement measurement. Due to the uncertainty of image location, the accuracy of the displacement measurement algorithm studied in the previous stage is limited. To improve the accuracy of image-type displacement measurement, a high-precision displacement measurement algorithm based on depth fusion of the grating projection pattern is proposed. First, a line-scan image sensor and parallel light source are placed on both sides of the calibration grating. The marking pattern on the calibration grating is projected onto the image sensor through illumination of the parallel light source to realize the projection imaging. Then, the centroid algorithm is used to calculate the centroid of each line in the collected image, and the mean value of the centroid group is determined. Finally, a linear function is used to fit multiple centroids to calculate the endpoints of the subdivision region, and the subdivision operation is carried out according to a ratio algorithm. To test the performance of the proposed algorithm, a linear displacement measurement device with a 250 mm range and an angular displacement measurement device with a 100 mm diameter grating are both used for experiments. After testing, the linear measurement accuracy of the proposed algorithm is improved from 4.63 to 1.26 µm, and the angular displacement measurement accuracy is enhanced from 8.87 to 2.88''. The research in this paper provides a theoretical basis for high-performance displacement measurement.

Anti-stain algorithm of angular displacement based on a single image sensor.

The displacement measuring technique is prone to failure within the industrial environment due to the influence of dust, oil, and other contaminants that stain the equipment. There is urgent demand for new anti-stain techniques. In today's image angular displacement measurement technology, the pixel array is used instead of the traditional photoelectric conversion element; this creates room for anti-stain improvement based on the image processing components. Based on a previous study on image-type angular displacement measurement technology, a single head image-type anti-stain algorithm is proposed in this paper that can remove the interference of small stains and ensure correct measurement value outputs. The influence of the stain on the calibration grating is first assessed based on the principle of image angular displacement measurement technology. An anti-stain algorithm based on the metal grating and multi-line fusion is proposed accordingly. The proposed algorithm is then tested on a circular grating with 38 mm diameter and ${{2}^{N}}\; = \;{256}$2N=256 lines in the circle. The results show that angle measurement output accuracy can be guaranteed when the number of lines covered by the stains is less than half of the coding-bits. This work may provide a technical basis for enhancing stain resistance in high-performance displacement measurement technology.

Extracellular fluid tonicity impacts sickle red blood cell deformability and adhesion.

Abnormal sickle red blood cell (sRBC) biomechanics, including pathological deformability and adhesion, correlate with clinical severity in sickle cell disease (SCD). Clinical intravenous fluids (IVFs) of various tonicities are often used during treatment of vaso-occlusive pain episodes (VOE), the major cause of morbidity in SCD. However, evidence-based guidelines are lacking, and there is no consensus regarding which IVFs to use during VOE. Further, it is unknown how altering extracellular fluid tonicity with IVFs affects sRBC biomechanics in the microcirculation, where vaso-occlusion takes place. Here, we report how altering extracellular fluid tonicity with admixtures of clinical IVFs affects sRBC biomechanical properties by leveraging novel in vitro microfluidic models of the microcirculation, including 1 capable of deoxygenating the sRBC environment to monitor changes in microchannel occlusion risk and an "endothelialized" microvascular model that measures alterations in sRBC/endothelium adhesion under postcapillary venular conditions. Admixtures with higher tonicities (sodium = 141 mEq/L) affected sRBC biomechanics by decreasing sRBC deformability, increasing sRBC occlusion under normoxic and hypoxic conditions, and increasing sRBC adhesion in our microfluidic human microvasculature models. Admixtures with excessive hypotonicity (sodium = 103 mEq/L), in contrast, decreased sRBC adhesion, but overswelling prolonged sRBC transit times in capillary-sized microchannels. Admixtures with intermediate tonicities (sodium = 111-122 mEq/L) resulted in optimal changes in sRBC biomechanics, thereby reducing the risk for vaso-occlusion in our models. These results have significant translational implications for patients with SCD and warrant a large-scale prospective clinical study addressing optimal IVF management during VOE in SCD.

Oxygen-dependent flow of sickle trait blood as an in vitro therapeutic benchmark for sickle cell disease treatments.

Although homozygous sickle cell disease is often clinically severe, the corresponding heterozygous state, sickle cell trait, is almost completely benign despite the fact that there is only a modest difference in sickle hemoglobin levels between the two conditions. In both conditions, hypoxia can lead to polymerization of sickle hemoglobin, changes in red cell mechanical properties, and impaired blood flow. Here, we test the hypothesis that differences in the oxygen-dependent rheological properties in the two conditions might help explain the difference in clinical phenotypes. We use a microfluidic platform that permits quantification of blood rheology under defined oxygen conditions in physiologically sized microchannels and under physiologic shear rates. We find that, even with its lower sickle hemoglobin concentration, sickle trait blood apparent viscosity increases with decreasing oxygen tension and may stop flowing under completely anoxic conditions, though far less readily than the homozygous condition. Sickle cell trait blood flow becomes impaired at significantly lower oxygen tension than sickle cell disease. We also demonstrate how sickle cell trait can serve as a benchmark for sickle cell disease therapies. We characterize the rheological effects of exchange transfusion therapy by mixing sickle blood with nonsickle blood and quantifying the transfusion targets for sickle hemoglobin composition below which the rheological response resembles sickle trait. These studies quantify the differences in blood flow phenotypes of sickle cell disease and sickle cell trait, and they provide a potentially powerful new benchmark for evaluating putative therapies in vitro.

A microfluidic platform to study the effects of vascular architecture and oxygen gradients on sickle blood flow.

Our goal was to develop a model of the microvasculature that would allow us to quantify changes in the rheology of sickle blood as it traverses the varying vessel sizes and oxygen tensions in the microcirculation. We designed and implemented a microfluidic model of the microcirculation that comprises a branching microvascular network and physiologic oxygen gradients. We used computational modeling to determine the parameters necessary to generate stable, linear gradients in our devices. Sickle blood from six unique patients was perfused through the microvascular network and subjected to varying oxygen gradients while we observed and quantified blood flow. We found that all sickle blood samples fully occluded the microvascular network when deoxygenated, and we observed that sickle blood could cause vaso-occlusions under physiologic oxygen gradients during the microvascular transit time. The number of occlusions observed under five unique oxygen gradients varied among the patient samples, but we generally observed that the number of occlusions decreased with increasing inlet oxygen tension. The model system we have developed is a valuable tool to address fundamental questions about where in the circulation sickle-cell vaso-occlusions are most likely to occur and to test new therapies.

Small-size, high-resolution angular displacement measurement technology based on an imaging detector.

It is challenging to design a photoelectric encoder that is small in size while ensuring it has sufficiently high resolution and accuracy. Traditional displacement measurement via the moiré fringe signal does not facilitate high resolution at small grate sizes; photoelectric and digital photo processing can significantly improve the angle measurement resolution over traditional techniques. The primary focus of this paper includes grating displacement coding and decoding, as well as the corresponding high-resolution subdivision and measurement error factors. A small-size absolute photographic encoder was designed (50 mm diameter) that exhibits resolution of 1.24'' (20 bit) with a standard deviation of error of 14.3''. The results presented here may provide a theoretical and technological foundation for further research on small-size, high-resolution photographic rotary encoders.

Deoxygenation Reduces Sickle Cell Blood Flow at Arterial Oxygen Tension.

The majority of morbidity and mortality in sickle cell disease is caused by vaso-occlusion: circulatory obstruction leading to tissue ischemia and infarction. The consequences of vaso-occlusion are seen clinically throughout the vascular tree, from the relatively high-oxygen and high-velocity cerebral arteries to the relatively low-oxygen and low-velocity postcapillary venules. Prevailing models of vaso-occlusion propose mechanisms that are relevant only to regions of low oxygen and low velocity, leaving a wide gap in our understanding of the most important pathologic process in sickle cell disease. Progress toward understanding vaso-occlusion is further challenged by the complexity of the multiple processes thought to be involved, including, but not limited to 1) deoxygenation-dependent hemoglobin polymerization leading to impaired rheology, 2) endothelial and leukocyte activation, and 3) altered cellular adhesion. Here, we chose to focus exclusively on deoxygenation-dependent rheologic processes in an effort to quantify their contribution independent of the other processes that are likely involved in vivo. We take advantage of an experimental system that, to our knowledge, uniquely enables the study of pressure-driven blood flow in physiologic-sized tubes at physiologic hematocrit under controlled oxygenation conditions, while excluding the effects of endothelium, leukocyte activation, adhesion, inflammation, and coagulation. We find that deoxygenation-dependent rheologic processes are sufficient to increase apparent viscosity significantly, slowing blood flow velocity at arterial oxygen tension even without additional contributions from inflammation, adhesion, and endothelial and leukocyte activation. We quantify the changes in apparent viscosity and define a set of functional regimes of sickle cell blood flow personalized for each patient that may be important in further dissecting mechanisms of in vivo vaso-occlusion as well as in assessing risk of patient complications, response to transfusion, and the optimization of experimental therapies in development.

Transcriptome Analysis of Key Genes Involved in the Initiation of Spermatogonial Stem Cell Differentiation.

PURPOSE: The purpose of this study was to screen the genes and pathways that are involved in spermatogonia stem cell (SSC) differentiation regulation during the transition from Aundiff to A1. Methods: RNA sequencing was performed to screen differentially expressed genes at 1 d and 2 d after SSC differentiation culture. KEGG pathway enrichment and GO function analysis were performed to reveal the genes and pathways related to the initiation of early SSC differentiation. RESULTS: The GO analysis showed that Rpl21, which regulates cell differentiation initiation, significantly increased after 1 day of SSC differentiation. The expressions of Fn1, Cd9, Fgf2, Itgb1, Epha2, Ctgf, Cttn, Timp2 and Fgfr1, which are related to promoting differentiation, were up-regulated after 2 days of SSC differentiation. The analysis of the KEGG pathway revealed that RNA transport is the most enriched pathway 1 day after SSC differentiation. Hspa2, which promotes the differentiation of male reproductive cells, and Cdkn2a, which participates in the cell cycle, were significantly up-regulated. The p53 pathway and MAPK pathway were the most enriched pathways 2 days after SSC differentiation. Cdkn1a, Hmga2, Thbs1 and Cdkn2a, microRNAs that promote cell differentiation, were also significantly up-regulated. CONCLUSIONS: RNA transport, the MAPK pathway and the p53 pathway may play vital roles in early SSC differentiation, and Rpl21, Fn1, Cd9, Fgf2, Itgb1, Epha2, Ctgf, Cttn, Timp2, Fgfr1, Hspa2, Cdkn2a, Cdkn1a, Hmga2 and Thbs1 are involved in the initiation of SSC differentiation. The findings of this study provide a reference for further revelations of the regulatory mechanism of SSC differentiation.

Exploring the therapeutic potential of Sirt6-enriched adipose stem cell-derived exosomes in myocardial ischemia-reperfusion injury: unfolding new epigenetic frontiers.

BACKGROUND: The management of myocardial ischemia-reperfusion injury (MIRI) presents continuous therapeutic challenges. NAD-dependent deacetylase Sirtuin 6 (Sirt6) plays distinct roles in various disease contexts and is hence investigated for potential therapeutic applications for MIRI. This study aimed to examine the impact of Sirt6-overexpressing exosomes derived from adipose stem cells (S-ASC-Exo) on MIRI, focusing on their influence on AIM2-pyroptosis and mitophagy processes. The sirtuin family of proteins, particularly Sirtuin 6 (Sirt6), play a pivotal role in these processes. This study aimed to explore the potential therapeutic effects of Sirt6-enriched exosomes derived from adipose stem cells (S-ASC-Exo) on regulating MIRI. RESULTS: Bioinformatic analysis revealed a significant downregulation of Sirt6 in MIRI subjected to control group, causing a consequential increase in mitophagy and pyroptosis regulator expressions. Therefore, our study revealed that Sirt6-enriched exosomes influenced the progression of MIRI through the regulation of target proteins AIM2 and GSDMD, associated with pyroptosis, and p62 and Beclin-1, related to mitophagy. The introduction of S-ASC-Exo inhibited AIM2-pyroptosis while enhancing mitophagy. Consequently, this led to a significant reduction of GSDMD cleavage and pyroptosis in endothelial cells, catalyzing a deceleration in the progression of atherosclerosis. Extensive in vivo and in vitro assays were performed to validate the expressions of these specific genes and proteins, which affirmed the dynamic modulation by Sirt6-enriched exosomes. Furthermore, treatment with S-ASC-Exo drastically ameliorated cardiac functions and limited infarct size, underlining their cardioprotective attributes. CONCLUSIONS: Our study underscores the potential therapeutic role of Sirt6-enriched exosomes in managing MIRI. We demonstrated their profound cardioprotective effect, evident in the enhanced cardiac function and attenuated tissue damage, through the strategic modulation of AIM2-pyroptosis and mitophagy. Given the intricate interplay between Sirt6 and the aforementioned processes, a comprehensive understanding of these pathways is essential to fully exploit the therapeutic potential of Sirt6. Altogether, our findings indicate the promise of Sirt6-enriched exosomes as a novel therapeutic strategy in treating ischemia-reperfusion injuries and cardiovascular diseases at large. Future research needs to underscore optimizing the balance of mitophagy during myocardial ischemia to avoid potential loss of normal myocytes.

Corrigendum to "Digital exclusion and functional dependence in older people: findings from five longitudinal cohort studies" eClinical Medicine 54 (2022) 101708.

[This corrects the article DOI: 10.1016/j.eclinm.2022.101708.].

Application of non-invasive prenatal testing to 91,280 spontaneous pregnancies and 3477 pregnancies conceived by in vitro fertilization.

BACKGROUND: Many clinical studies based on spontaneous pregnancies (SPs) have demonstrated the superiority of non-invasive prenatal testing (NIPT), and the question of whether this technology is suitable for offspring conceived by assisted reproductive technology has attracted attention. This study aimed to evaluate the application value of NIPT in screening for trisomy (T)21, T18, T13 and sex chromosome aneuploidy (SCA) in pregnant women who conceived by in vitro fertilization (IVF). RESULTS: In total, there were 804 high-risk cases [0.88% (804/91280), singleton = 795, twin = 9] in the SP group. Among the 558 invasive prenatal diagnosis (IPD) cases (singleton = 556, twin = 2), 343 (singleton = 342, twin = 1) were true positive, including 213 cases of T21, 28 of T18, 5 of T13 and 97 (singleton = 96, twin = 1) of SCA. The positive predictive values (PPVs) of T21, T18, T13, SCA and T21/T18/T13 combined in singleton pregnancy were 89.12% (213/239), 51.85% (28/54), 21.74% (5/23), 40.00% (96/240), and 77.85% (246/316), respectively, and the PPV of SCA in twin pregnancy was 100.00%. In the IVF group, IPD was performed in 19 (singleton = 16, twin = 3) of the 27 high-risk cases [0.78% (27/3477), singleton = 16, twin = 3], of which 9 (singleton = 8, twin = 1) were true positive, including 5 cases (singleton = 4, twin = 1) of T21 and 4 of SCA. The PPVs of singleton T21, SCA and T21/T18/T13 combined were 66.67% (4/6), 50.00% (4/8) and 57.14% (4/7), respectively, and the PPV of twin T21 was 100.00% (1/1). There were no significant differences in PPV among T21, SCA and T21/T18/T13 combined in singletons between the groups (89.12% vs. 66.67%, p = 0.09; 40.00% vs. 50.00%, p = 0.57; 77.85% vs. 57.14%, p = 0.20). The sensitivity and specificity were higher for singleton and twin pregnancies in the two groups. Based on follow-up results, 1 case of false negative T21 was found in the singleton SP group. Additionally, the mean foetal fraction (FF) of the IVF group was lower than that of the SP group (11.23% vs. 10.51%, p < 0.05). CONCLUSION: NIPT has high sensitivity and specificity in screening chromosomal aneuploidies in both IVF pregnancy and spontaneous pregnancy, so it is an ideal screening method for IVF pregnancy.

High-fat diet alters the radiation tolerance of female mice and the modulatory effect of melatonin.

High-fat diet (HFD) increases the risk of developing malignant tumors. Ionizing radiation (IR) is used as an adjuvant treatment in oncology. In this study, we investigated the effects of an 8-week 35% fat HFD on the tolerance to IR and the modulatory effect of melatonin (MLT). The results of lethal dose irradiation survival experiments revealed that the 8-week HFD altered the radiation tolerance of female mice and increased their radiosensitivity, whereas it had no comparable effects on males. Pre-treatment with MLT was, however, found to attenuate the radiation-induced hematopoietic damage in mice, promote intestinal structural repair after whole abdominal irradiation (WAI), and enhance the regeneration of Lgr5+ intestinal stem cells. 16S rRNA high-throughput sequencing and untargeted metabolome analyses revealed that HFD consumption and WAI sex-specifically altered the composition of intestinal microbiota and fecal metabolites and that MLT supplementation differentially modulated the composition of the intestinal microflora in mice. However, in both males and females, different bacteria were associated with the modulation of the metabolite 5-methoxytryptamine. Collectively, the findings indicate that MLT ameliorates the radiation-induced damage and sex-specifically shapes the composition of the gut microbiota and metabolites, protecting mice from the adverse side effects associated with HFD and IR.

Transcriptome Analysis in High Temperature Inhibiting Spermatogonial Stem Cell Differentiation In Vitro.

As one of the factors of male infertility, high temperature induces apoptosis of differentiated spermatogenic cells, sperm DNA oxidative damage, and changes in morphology and function of Sertoli cells. Spermatogonial stem cells (SSCs) are a type of germline stem cells that maintain spermatogenesis through self-renewal and differentiation. At present, however, the effect of high temperature on SSC differentiation remains unknown. In this study, an in vitro SSC differentiation model was used to investigate the effect of heat stress treatment on SSC differentiation, and RNA sequencing (RNA-seq) was used to enrich the key genes and pathways in high temperature inhibiting SSC differentiation. Results show that 2 days of 37 °C or 43 °C (30 min per day) heat stress treatment significantly inhibited SSC differentiation. The differentiation-related genes c-kit, stra8, Rec8, Sycp3, and Ovol1 were down-regulated after 2 and 4 days of heat stress at 37 °C. The transcriptome of SSCs was significantly differentially expressed on days 2 and 4 after heat stress treatment at 37 °C. In total, 1660 and 7252 differentially expressed genes (DEGs) were identified by RNA-seq in SSCs treated with heat stress at 37 °C for 2 and 4 days, respectively. KEGG pathway analysis showed that p53, ribosome, and carbon metabolism signaling pathways promoting stem cell differentiation were significantly enriched after heat stress treatment at 37 °C. In conclusion, 37 °C significantly inhibited SSC differentiation, and p53, ribosome, and carbon metabolism signaling pathways were involved in this differentiation inhibition process. The results of this study provide a reference for further investigation into the mechanism by which high temperature inhibits SSC differentiation.

Association of Thyroid-Stimulating Hormone With All-Cause Mortality: A 2-Sample Mendelian Randomization Study.

CONTEXT: Thyroid-stimulating hormone (TSH), as the most sensitive and specific marker of thyroid status, is associated with multiple health outcomes, including mortality. However, whether TSH levels are causally associated with the risk of mortality remains unclear. OBJECTIVE: This study aims to investigate the causal association between TSH levels and all-cause mortality using Mendelian randomization (MR) analyses. METHODS: MR analyses using single-nucleotide polymorphisms (SNPs) associated with TSH levels (P < 5 × 10-8) as instruments. Mortality data were obtained from the UK Biobank, including 384 344 participants who were recruited from 22 assessment centers across the UK taken between 2006 and 2010. Cox proportional hazards regression was used to estimate the association of the TSH genetic risk score (GRS) with all-cause and cause-specific mortality. RESULTS: 15 557 individuals died during a median of 9.00 years of follow-up in the UK Biobank. A total of 70 SNPs were included in the MR analysis. The main MR analyses showed that 1 SD increase in TSH was associated with a decreased risk of all-cause mortality (OR 0.972, 95% CI 0.948-0.996), which may be largely attributed to respiratory disease mortality (OR 0.881, 95% CI 0.805-0.963). The multivariable hazard ratios (HRs) (95% CI) of all-cause mortality across 3 TSH GRS categories were 1.00 (reference), 0.976 (0.940-1.014), and 0.947 (0.911-0.985), respectively (P for trend < .01). Moreover, except digestive diseases mortality, genetically predicted TSH levels were negatively associated with mortality from CVD, cancer, noncancer diseases causes, and dementia, although not statistically significant. CONCLUSION: Higher TSH levels were causally associated with lower risk of all-cause mortality, which may be largely attributed to respiratory disease mortality.

Digital exclusion and functional dependence in older people: Findings from five longitudinal cohort studies.

Background: Older people are more likely to be excluded from the digital world, and this has been linked to poor health outcomes. The extent and direction of the influence of digital exclusion on functional dependency is, however, not well understood. We aimed to investigate the association between digital exclusion and functional dependency among older adults from high-income countries (HICs) and low- and middle-income countries (LMICs). Methods: In this multicohort study, we pooled individual-level data from five longitudinal cohort studies that included nationally representative samples of older adults across 23 countries, including the Health and Retirement Study (HRS), the English Longitudinal Study of Aging (ELSA), the Survey of Health, Ageing and Retirement in Europe (SHARE), the China Health and Retirement Longitudinal Study (CHARLS), and the Mexican Health and Aging Study (MHAS). The digital exclusion was recorded as an absence from internet use by self-reported. We assessed basic activities of daily living (BADL) and instrumental activities of daily living (IADL), and we used interval-of-need methods to categorize the functional dependency. We applied generalized estimating equations models fitting Poisson model to investigate the association of digital exclusion with difficulties in BADL or IADL and functional dependency, adjusting for the causal-directed-acyclic-graph (DAG) minimal sufficient adjustment set (MSAS), including gender, age level, labour force status, education, household wealth level, marital status, and co-residence with children. Findings: We included 108,621 participants recruited between 2010 and 2018 with a median follow-up of 3 phrases. Digital exclusion in older adults varied across countries, ranging from 23.8% in Denmark (SHARE) to 96.9% in China (CHARLS). According to the crude model, digital exclusion was significantly associated with functional dependency. In the MSAS-adjusted model, those associations remained statistically significant: HRS (incidence rate ratio [IRR] = 1.40, 95% confidence interval [CI] 1.34-1.48 for BADL; 1.71 [1.61-1.82] for IADL), ELSA (1.31 [1.22-1.40] in BADL and 1.37 [1.28-1.46] in IADL), SHARE (1.69 [1.61-1.78] in BADL and 1.70 [1.63-1.78] in IADL), CHARLS (2.15 [1.73-2.67] in BADL and 2.59 [2.06-3.25] in IADL), and MHAS (1.15 [1.09-1.21] in BADL and 1.17 [1.09-1.25] in IADL). In the subgroup analyses, the associations were more pronounced in the oldest-old (aged ≥ 80 years old). Interpretation: There is a substantial proportion of older adults who are excluded from the Internet, especially those in LMIC. Older people excluded from the Internet regardless of whether they live in HICs or LMICs are more likely to develop functional dependency. It should be made a priority to remove barriers to Internet access in order to assist older people in maintaining their independence and, consequently, to reduce the care burden associated with the ageing population worldwide. Funding: The National Natural Science Foundation of China (No. 71904004).

Acrylamide fragment inhibitors that induce unprecedented conformational distortions in enterovirus 71 3C and SARS-CoV-2 main protease.

RNA viruses are critically dependent upon virally encoded proteases to cleave the viral polyproteins into functional proteins. Many of these proteases exhibit a similar fold and contain an essential catalytic cysteine, offering the opportunity to inhibit these enzymes with electrophilic small molecules. Here we describe the successful application of quantitative irreversible tethering (qIT) to identify acrylamide fragments that target the active site cysteine of the 3C protease (3Cpro) of Enterovirus 71, the causative agent of hand, foot and mouth disease in humans, altering the substrate binding region. Further, we re-purpose these hits towards the main protease (Mpro) of SARS-CoV-2 which shares the 3C-like fold and a similar active site. The hit fragments covalently link to the catalytic cysteine of Mpro to inhibit its activity. We demonstrate that targeting the active site cysteine of Mpro can have profound allosteric effects, distorting secondary structures to disrupt the active dimeric unit.