HumanIslets: An integrated platform for human islet data access and analysis.

Comprehensive molecular and cellular phenotyping of human islets can enable deep mechanistic insights for diabetes research. We established the Human Islet Data Analysis and Sharing (HI-DAS) consortium to advance goals in accessibility, usability, and integration of data from human islets isolated from donors with and without diabetes at the Alberta Diabetes Institute (ADI) IsletCore. Here we introduce HumanIslets.com, an open resource for the research community. This platform, which presently includes data on 547 human islet donors, allows users to access linked datasets describing molecular profiles, islet function and donor phenotypes, and to perform various statistical and functional analyses at the donor, islet and single-cell levels. As an example of the analytic capacity of this resource we show a dissociation between cell culture effects on transcript and protein expression, and an approach to correct for exocrine contamination found in hand-picked islets. Finally, we provide an example workflow and visualization that highlights links between type 2 diabetes status, SERCA3b Ca2+-ATPase levels at the transcript and protein level, insulin secretion and islet cell phenotypes. HumanIslets.com provides a growing and adaptable set of resources and tools to support the metabolism and diabetes research community.

Relationship between increased maternal serum free human chorionic gonadotropin levels in the second trimester and adverse pregnancy outcomes: a retrospective cohort study.

BACKGROUND: A retrospective cohort study was conducted to collect the data of pregnant women who received hospital delivery in Hangzhou Women's Hospital from January 2018 to December 2020, and who participated in the second trimester (15-20+6 weeks) of free beta human chorionic gonadotropin (free ß-hCG). And the study was conducted to explore the relationship between maternal serum free ß-hCG and adverse pregnancy outcomes (APO). METHODS: We retrospectively analyzed the clinical data of 1,978 women in the elevated maternal serum free ß-hCG group (free ß-hCG ≥ 2.50 multiples of the median, MoM) and 20,767 women in the normal group (0.25 MoM ≤ free ß-hCG < 2.50 MoM) from a total of 22,745 singleton pregnancies, and modified Poisson regression analysis was used to calculate risk ratios (RRs) and 95% confidence intervals (CI) of the two groups. RESULTS: The gravidity and parity in the elevated free ß-hCG group were lower, and the differences between the groups were statistically significant (all, P < 0.05). The risks of polyhydramnios, preeclampsia, and hyperlipidemia, were increased in women with elevated free ß-hCG levels (RRs: 1.996, 95% CI: 1.322-3.014; 1.469, 95% CI: 1.130-1.911 and 1.257, 95% CI: 1.029-1.535, respectively, all P < 0.05), intrauterine growth restriction (IUGR) and female infants were also likely to happen (RRs = 1.641, 95% CI: 1.103-2.443 and 1.101, 95% CI: 1.011-1.198, both P < 0.05). Additionally, there was an association between elevated AFP and free ß-hCG levels in second-trimester (RR = 1.211, 95% CI: 1.121-1.307, P < 0.001). CONCLUSIONS: APOs, such as polyhydramnios, preeclampsia, and hyperlipidemia, were increased risks of elevated free ß-hCG levels, IUGR and female infants were also likely to happen. Furthermore, there was an association between elevated AFP levels and elevated free ß-hCG levels in second-trimester. We recommend prenatal monitoring according to the elevated maternal serum free ß-hCG level and the occurrence of APO.

Perinatal characteristics and pregnancy outcomes of advanced maternal age women with gestational diabetes mellitus: A retrospective cohort study.

Background and Aims: The prevalence of gestational diabetes mellitus (GDM) continues to increase, and the phenomenon of women giving birth at an older age is becoming more common worldwide. Less is known abouts the impact of GDM combined with advanced maternal age (AMA) on pregnancy outcomes. To explore the impact of AMA complicated with GDM on pregnancy outcomes. Methods: This study included 34,602 pregnancies between 2018 and 2020 in Hangzhou, China. The pregnant women were divided into four groups according to advanced age (≥35 years) and GDM as follows: AMA women without GDM (non-AGDM) group (n = 2614), young pregnant women with GDM (YGDM) group (n = 4016), AMA women with GDM (AGDM) group (n = 850), and young pregnant women without GDM (non-YGDM) group (n = 27,122). Univariate analysis was carried out by Mann-Whitney U test or Pearson's χ 2 test. Multivariate logistic regression analysis was used to investigate the effect of AMA and GDM on pregnancy outcomes. Results: Multivariate logistic regression analysis showed that in the comparison against non-YGDM garoup, the ORs of fetal chromosome abnormality, parity, urgent cesarean section, gravidity, scheduled cesarean section, body mass index (BMI) ≥30 kg/m2, pre-eclampsia, thrombocytopenia, hyperlipidemia, BMI 25-29.9 kg/m2, blood urea nitrogen, fasting blood glucose, and creatinine in AGDM group were 16.044, 4.284, 3.530, 3.284, 3.257, 2.049, 1.935, 1.898, 1.690, 1.471, 1.304, 1.216, and 1.026 (all p < 0.05). Conclusions: The prevalence of pregnant women with AGDM was 2.46% in Hang Zhou, China. The increasing gravidity of AMA women was related to a greater risk of GDM. The AGDM group associated with a greater risks of chromosomal abnormality in offspring and cesarean section, especially urgent cesarean section.

Quality assessment of the preparation and storage of leukocyte-depleted pooled platelet concentrates.

OBJECTIVE: To explore the feasibility of using a disposable platelet storage bag containing a leukocyte filter to prepare leukocyte-depleted pooled platelet concentrates with the buffy coat method. METHODS: 150 bags of whole blood samples (400 mL/bag) were stored overnight at 22 ± 2°C, and buffy coats were separated on Day 2, then 5 units of ABO homotypic buffy coat and 1 unit of plasma were pooled into a disposable platelet storage bag containing a leukocyte filter to prepare leukocyte-depleted pooled platelet concentrates and stored in a Platelet Agitator. On Day 2, 4, 5 and 7 after the collection of whole blood, platelet content, pH value, pO2, pCO2, glucose (GLU), ATP, and other quality indicators were measured. RESULTS: The quality indicators of leukocyte-depleted pooled platelet concentrates met the requirements for leukocyte-depleted aphaeresis platelets in the Chinese national standard Quality Requirements for Whole Blood and Blood Components (GB18469-2012). With the prolongation of storage time, MPV and PDW of platelets gradually increased, pH value, bicarbonate, and GLU gradually decreased, LA, LDH, and ATP gradually increased, pO2 slightly increased, pCO2 decreased, and HSR had no significant change. ESC decreased significantly on Day 7, CD62p decreased first and then increased, sP-selectin and GP V increased first and then decreased, but the results on Day 7 were higher than those on Day 2. CONCLUSION: The quality of leukocyte-depleted pooled platelet concentrates prepared by the buffy coat method using disposable platelet storage bags containing a leukocyte filter was comparable to that of leukocyte-depleted apheresis platelets, and could be used clinically.

A Targeted Multi-Crystalline Manganese Oxide as a Tumor-Selective Nano-Sized MRI Contrast Agent for Early and Accurate Diagnosis of Tumors.

Introduction: Magnetic resonance imaging (MRI) is an important tool for the accurate diagnosis of malignant tumors in clinical settings. However, the lack of tumor-specific MRI contrast agents limits diagnostic accuracy. Methods: Herein, we developed αv integrin receptor-targeting multi-crystalline manganese oxide (MCMO) as a novel MRI contrast agent for accurate diagnosis of tumors by coupling iRGD cyclopeptide PEGylation polymer onto the surface of MCMO (iRGD-pMCMO). Results: The MCMO consisted of numerous small crystals and exhibited an oval structure of 200 nm in size. The iRGD-pMCMO actively recognizes tumor cells and effectively accumulates at the tumor site, consequently releasing abundant Mn2+ ions in a weakly acidic and high-GSH-expressing tumor microenvironment. Subsequently, Mn2+ ions interact with cellular GSH to form Mn-GSH chelates, enabling efficient T1-weighted MR contrast imaging. In vivo experiments indicated that iRGD-pMCMO significantly improved T1-weighted images, achieving an accurate diagnosis of subcutaneous and orthotopic tumors. The results verified that the T1 contrast effect of iRGD-pMCMO was closely associated with the expression of GSH in tumor cells. Conclusion: Altogether, the novel tumor-targeting, highly sensitive MRI contrast agent developed in this study can improve the accuracy of MRI for tumor diagnosis.

A role and mechanism for redox sensing by SENP1 in ß-cell responses to high fat feeding.

Pancreatic ß-cells respond to metabolic stress by upregulating insulin secretion, however the underlying mechanisms remain unclear. Here we show, in ß-cells from overweight humans without diabetes and mice fed a high-fat diet for 2 days, insulin exocytosis and secretion are enhanced without increased Ca2+ influx. RNA-seq of sorted ß-cells suggests altered metabolic pathways early following high fat diet, where we find increased basal oxygen consumption and proton leak, but a more reduced cytosolic redox state. Increased ß-cell exocytosis after 2-day high fat diet is dependent on this reduced intracellular redox state and requires the sentrin-specific SUMO-protease-1. Mice with either pancreas- or ß-cell-specific deletion of this fail to up-regulate exocytosis and become rapidly glucose intolerant after 2-day high fat diet. Mechanistically, redox-sensing by the SUMO-protease requires a thiol group at C535 which together with Zn+-binding suppresses basal protease activity and unrestrained ß-cell exocytosis, and increases enzyme sensitivity to regulation by redox signals.

HNF1α maintains pancreatic α and ß cell functions in primary human islets.

HNF1A haploinsufficiency underlies the most common form of human monogenic diabetes (HNF1A-maturity onset diabetes of the young [HNF1A-MODY]), and hypomorphic HNF1A variants confer type 2 diabetes risk. But a lack of experimental systems for interrogating mature human islets has limited our understanding of how the transcription factor HNF1α regulates adult islet function. Here, we combined conditional genetic targeting in human islet cells, RNA-Seq, chromatin mapping with cleavage under targets and release using nuclease (CUT&RUN), and transplantation-based assays to determine HNF1α-regulated mechanisms in adult human pancreatic α and ß cells. Short hairpin RNA-mediated (shRNA-mediated) suppression of HNF1A in primary human pseudoislets led to blunted insulin output and dysregulated glucagon secretion after transplantation in mice, recapitulating phenotypes observed in patients with diabetes. These deficits corresponded with altered expression of genes encoding factors critical for hormone secretion, including calcium channel subunits, ATPase transporters, and extracellular matrix constituents. Additionally, HNF1A loss led to upregulation of transcriptional repressors, providing evidence for a mechanism of transcriptional derepression through HNF1α. CUT&RUN mapping of HNF1α DNA binding sites in primary human islets imputed a subset of HNF1α-regulated genes as direct targets. These data elucidate mechanistic links between HNF1A loss and diabetic phenotypes in mature human α and ß cells.

Deletion of Carboxypeptidase E in ß-Cells Disrupts Proinsulin Processing but Does Not Lead to Spontaneous Development of Diabetes in Mice.

Carboxypeptidase E (CPE) facilitates the conversion of prohormones into mature hormones and is highly expressed in multiple neuroendocrine tissues. Carriers of CPE mutations have elevated plasma proinsulin and develop severe obesity and hyperglycemia. We aimed to determine whether loss of Cpe in pancreatic ß-cells disrupts proinsulin processing and accelerates development of diabetes and obesity in mice. Pancreatic ß-cell-specific Cpe knockout mice (ßCpeKO; Cpefl/fl x Ins1Cre/+) lack mature insulin granules and have elevated proinsulin in plasma; however, glucose-and KCl-stimulated insulin secretion in ßCpeKO islets remained intact. High-fat diet-fed ßCpeKO mice showed weight gain and glucose tolerance comparable with those of Wt littermates. Notably, ß-cell area was increased in chow-fed ßCpeKO mice and ß-cell replication was elevated in ßCpeKO islets. Transcriptomic analysis of ßCpeKO ß-cells revealed elevated glycolysis and Hif1α-target gene expression. On high glucose challenge, ß-cells from ßCpeKO mice showed reduced mitochondrial membrane potential, increased reactive oxygen species, reduced MafA, and elevated Aldh1a3 transcript levels. Following multiple low-dose streptozotocin injections, ßCpeKO mice had accelerated development of hyperglycemia with reduced ß-cell insulin and Glut2 expression. These findings suggest that Cpe and proper proinsulin processing are critical in maintaining ß-cell function during the development of hyperglycemia. ARTICLE HIGHLIGHTS: Carboxypeptidase E (Cpe) is an enzyme that removes the carboxy-terminal arginine and lysine residues from peptide precursors. Mutations in CPE lead to obesity and type 2 diabetes in humans, and whole-body Cpe knockout or mutant mice are obese and hyperglycemic and fail to convert proinsulin to insulin. We show that ß-cell-specific Cpe deletion in mice (ßCpeKO) does not lead to the development of obesity or hyperglycemia, even after prolonged high-fat diet treatment. However, ß-cell proliferation rate and ß-cell area are increased, and the development of hyperglycemia induced by multiple low-dose streptozotocin injections is accelerated in ßCpeKO mice.

Integrating genetics with single-cell multiomic measurements across disease states identifies mechanisms of beta cell dysfunction in type 2 diabetes.

Dysfunctional pancreatic islet beta cells are a hallmark of type 2 diabetes (T2D), but a comprehensive understanding of the underlying mechanisms, including gene dysregulation, is lacking. Here we integrate information from measurements of chromatin accessibility, gene expression and function in single beta cells with genetic association data to nominate disease-causal gene regulatory changes in T2D. Using machine learning on chromatin accessibility data from 34 nondiabetic, pre-T2D and T2D donors, we identify two transcriptionally and functionally distinct beta cell subtypes that undergo an abundance shift during T2D progression. Subtype-defining accessible chromatin is enriched for T2D risk variants, suggesting a causal contribution of subtype identity to T2D. Both beta cell subtypes exhibit activation of a stress-response transcriptional program and functional impairment in T2D, which is probably induced by the T2D-associated metabolic environment. Our findings demonstrate the power of multimodal single-cell measurements combined with machine learning for characterizing mechanisms of complex diseases.

ZnO-decorated SiC@C hybrids with strong electromagnetic absorption.

A novel strategy is provided to improve the absorption of SiC nanomaterials through surface carbonization of SiC nanowires and hydrolysis. SiC@C-ZnO composites were synthesized with different dosages of ZnNO3·6H2O. Composition, microstructure, and electromagnetic properties of the composites were characterized and analyzed. Results from TEM and XRD show that crystalline ZnO particles adhere to the surface of amorphous carbon, and the ZnO content increases as a function of a dosage of ZnNO3·6H2O. The as-prepared SiC@C-ZnO hybrids exhibit effective electromagnetic absorption, which is related to a synergy effect of different dielectric loss processes. The minimum reflection loss reached -65.4 dB at 11 GHz at a sample thickness of 3.1 mm, while the effective absorption bandwidth (EAB) reached 7 GHz at a sample thickness of 2.56 mm. Furthermore, the EAB of the samples can also cover the whole X band and Ku band at small sample thicknesses (2.09-3.47 mm). The excellent properties of the materials suggest great prospect as electromagnetic absorbers.

Correlation between elevated maternal serum alpha-fetoprotein and ischemic placental disease: a retrospective cohort study.

BACKGROUND: To evaluate the correlation between elevated maternal serum alpha-fetoprotein (AFP) in the second trimester and ischemic placental disease (IPD). METHODS: A retrospective cohort study was conducted to analyze the data of 22,574 pregnant women who delivered in the Department of Obstetrics at Hangzhou Women's Hospital from 2018 to 2020, and were screened for maternal serum AFP and free beta-human chorionic gonadotropin (free ß-hCG) in the second trimester. The pregnant women were divided into two groups: elevated maternal serum AFP group (n = 334, 1.48%); and normal group (n = 22,240, 98.52%). Mann-Whitney U-test or Chi-square test was used for continuous or categorical data. Modified Poisson regression analysis was used to calculate the relative risk (RR) and 95% confidence interval (CI) of the two groups. RESULTS: The AFP MoM and free ß-hCG MoM in the elevated maternal serum AFP group were higher than the normal group (2.25 vs. 0.98, 1.38 vs. 1.04) and the differences were all statistically significant (all P < .001). Placenta previa, hepatitis B virus carrying status of pregnant women, premature rupture of membranes (PROM), advanced maternal age (≥35 years), increased free ß-hCG MoM, female infants, and low birth weight (RR: 2.722, 2.247, 1.769, 1.766, 1.272, 0.624, 2.554 respectively) were the risk factors for adverse maternal pregnancy outcomes in the elevated maternal serum AFP group. CONCLUSIONS: Maternal serum AFP levels during the second trimester can monitor IPD, such as IUGR, PROM, and placenta previa. Maternal women with high serum AFP levels are more likely to deliver male fetuses and low birth weight infants. Finally, the maternal age (≥35 years) and hepatitis B carriers also increased maternal serum AFP significantly.

Admission Heart Rate and Mortality in Critically Ill Patients with Acute Aortic Dissection.

The association between admission heart rate (HR) and the mortality of critically ill patients with acute aortic dissection (AAD) remains unclear.The data were extracted from the Medical Information Mart for Intensive Care (MIMIC-III) database. Cox regression models and Kaplan-Meier (KM) survival curve were used to explore the association between admission HR and 90-day, 1-year, and 3-year mortality in patients with AAD. Sensitivity analyses were conducted to assess potential bias.A total of 374 eligible AAD patients were included and divided in 4 groups according to admission HR (HR ≤ 70, 71-80, 81-90, and > 90 beats per minute (bpm) ). The patients with AAD in the group with HR > 90 bpm had higher 90-day, 1-year, and 3-year mortality than those in the groups with HR ≤ 70, 71-80, and 81-90 bpm. After adjusting for age, sex, BMI, systolic blood pressure, diastolic blood pressure, SOFA score, SAPSII score, Stanford type, hypertension, coronary artery disease, liver disease, atrial fibrillation, valvular disease, intensive care unit mechanical ventilation, aortic surgery, and thoracic endovascular aortic repair, patients with admission HR > 90 bpm had a higher risk of 90-day, 1-year, and 3-year mortality [adjusted hazard ratio, 95% confidence interval, 5.14 (2.22-11.91) P < 0.001; 4.31 (2.10-8.84) P < 0.001; 3.01 (1.66-5.46) P < 0.001] than those with HR 81-90 bpm. The 90-day, 1-year, and 3-year mortality were similar among the groups with HR ≤ 70, 71-80, and 81-90 bpm.Admission HR > 90 bpm was independently associated with all-cause mortality in critically ill AAD patients, either type A or B aortic dissection.

Integration of single-cell multiomic measurements across disease states with genetics identifies mechanisms of beta cell dysfunction in type 2 diabetes.

Altered function and gene regulation of pancreatic islet beta cells is a hallmark of type 2 diabetes (T2D), but a comprehensive understanding of mechanisms driving T2D is still missing. Here we integrate information from measurements of chromatin activity, gene expression and function in single beta cells with genetic association data to identify disease-causal gene regulatory changes in T2D. Using machine learning on chromatin accessibility data from 34 non-diabetic, pre-T2D and T2D donors, we robustly identify two transcriptionally and functionally distinct beta cell subtypes that undergo an abundance shift in T2D. Subtype-defining active chromatin is enriched for T2D risk variants, suggesting a causal contribution of subtype identity to T2D. Both subtypes exhibit activation of a stress-response transcriptional program and functional impairment in T2D, which is likely induced by the T2D-associated metabolic environment. Our findings demonstrate the power of multimodal single-cell measurements combined with machine learning for identifying mechanisms of complex diseases.

Gamma-glutamyl transpeptidase to platelet and gamma-glutamyl transpeptidase to lymphocyte ratio in a sample of Chinese Han population.

BACKGROUND: Gamma-glutamyl transpeptidase to platelet ratio (GPR) and gamma-glutamyl transpeptidase to lymphocyte ratio (GLR) are assumed to be prognostic factors in liver fibrosis, cirrhosis and hepatocellular carcinoma. However, the reference values of GPR and GLR were not known. OBJECTIVES: The study aimed to investigate the reference ranges of GPR and GLR in Chinese Han population in Chaoshan region in South China. METHODS: A retrospective study was conducted in the First Affiliated Hospital of Shantou University Medical College in South China. 2400 healthy adults aged 20~79 years were included. GPR and GLR were determined. RESULTS: Of 2400 healthy adults, 1200 men and 1200 women were included. The median GPR and GLR for men were 0.22 and 11.28, for women were 0.18 and 7.86, respectively. The 95% reference range of GPR in normal male and female are 0.09~0.54 and 0.08~0.55, GLR are 4.55~29.64 and 3.52~23.08, respectively. The male had a higher GPR at age 20~49 than the female while the GPR at age 60~79 was higher in the female than in the male. The GPR was affected by age, decreased with aging in male and increased in female. The GLR was higher in the male than in the female and varied with aging in the female but not in the male. CONCLUSION: The study provides reference data on GPR and GLR from different age and sex groups in South China. GPR and GLR varied with age and sex.

Electrical recordings from dendritic spines of adult mouse hippocampus and effect of the actin cytoskeleton.

Dendritic spines (DS) are tiny protrusions implicated in excitatory postsynaptic responses in the CNS. To achieve their function, DS concentrate a high density of ion channels and dynamic actin networks in a tiny specialized compartment. However, to date there is no direct information on DS ionic conductances. Here, we used several experimental techniques to obtain direct electrical information from DS of the adult mouse hippocampus. First, we optimized a method to isolate DS from the dissected hippocampus. Second, we used the lipid bilayer membrane (BLM) reconstitution and patch clamping techniques and obtained heretofore unavailable electrical phenotypes on ion channels present in the DS membrane. Third, we also patch clamped DS directly in cultured adult mouse hippocampal neurons, to validate the electrical information observed with the isolated preparation. Electron microscopy and immunochemistry of PDS-95 and NMDA receptors and intrinsic actin networks confirmed the enrichment of the isolated DS preparation, showing open and closed DS, and multi-headed DS. The preparation was used to identify single channel activities and "whole-DS" electrical conductance. We identified NMDA and Ca2+-dependent intrinsic electrical activity in isolated DS and in situ DS of cultured adult mouse hippocampal neurons. In situ recordings in the presence of local NMDA, showed that individual DS intrinsic electrical activity often back-propagated to the dendrite from which it sprouted. The DS electrical oscillations were modulated by changes in actin cytoskeleton dynamics by addition of the F-actin disrupter agent, cytochalasin D, and exogenous actin-binding proteins. The data indicate that DS are elaborate excitable electrical devices, whose activity is a functional interplay between ion channels and the underlying actin networks. The data argue in favor of the active contribution of individual DS to the electrical activity of neurons at the level of both the membrane conductance and cytoskeletal signaling.

Beta-cell specific Insr deletion promotes insulin hypersecretion and improves glucose tolerance prior to global insulin resistance.

Insulin receptor (Insr) protein is present at higher levels in pancreatic ß-cells than in most other tissues, but the consequences of ß-cell insulin resistance remain enigmatic. Here, we use an Ins1cre knock-in allele to delete Insr specifically in ß-cells of both female and male mice. We compare experimental mice to Ins1cre-containing littermate controls at multiple ages and on multiple diets. RNA-seq of purified recombined ß-cells reveals transcriptomic consequences of Insr loss, which differ between female and male mice. Action potential and calcium oscillation frequencies are increased in Insr knockout ß-cells from female, but not male mice, whereas only male ßInsrKO islets have reduced ATP-coupled oxygen consumption rate and reduced expression of genes involved in ATP synthesis. Female ßInsrKO and ßInsrHET mice exhibit elevated insulin release in ex vivo perifusion experiments, during hyperglycemic clamps, and following i.p. glucose challenge. Deletion of Insr does not alter ß-cell area up to 9 months of age, nor does it impair hyperglycemia-induced proliferation. Based on our data, we adapt a mathematical model to include ß-cell insulin resistance, which predicts that ß-cell Insr knockout improves glucose tolerance depending on the degree of whole-body insulin resistance. Indeed, glucose tolerance is significantly improved in female ßInsrKO and ßInsrHET mice compared to controls at 9, 21 and 39 weeks, and also in insulin-sensitive 4-week old males. We observe no improved glucose tolerance in older male mice or in high fat diet-fed mice, corroborating the prediction that global insulin resistance obscures the effects of ß-cell specific insulin resistance. The propensity for hyperinsulinemia is associated with mildly reduced fasting glucose and increased body weight. We further validate our main in vivo findings using an Ins1-CreERT transgenic line and find that male mice have improved glucose tolerance 4 weeks after tamoxifen-mediated Insr deletion. Collectively, our data show that ß-cell insulin resistance in the form of reduced ß-cell Insr contributes to hyperinsulinemia in the context of glucose stimulation, thereby improving glucose homeostasis in otherwise insulin sensitive sex, dietary and age contexts.

Reference intervals for coagulation tests in adults with different ABO blood types.

INTRODUCTION: Coagulation tests are affected by many factors, such as age, race, and gestation. Although coagulation test results vary by ABO blood type, reference intervals of different ABO blood groups remain to be determined. This study aims to investigate the reference ranges of coagulation tests for different ABO blood groups in the Han population in South China. METHODS: A retrospective study was conducted in the First Affiliated Hospital of Shantou University Medical College. In all, 9600 individuals aged between 20 and 79 years were included. Coagulation tests, including prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (aPTT), thrombin time, and fibrinogen, were performed. RESULTS: There was a significant difference in PT, INR, and aPTT among ABO blood groups. PT and INR varied slightly between ABO blood groups. There was a higher aPTT value in individuals in the O blood group than in those in non-O blood groups, in both males and females across the included age range. No differences were found in thrombin time and fibrinogen between the ABO blood groups. CONCLUSION: The study provides reference data on coagulation tests from ABO blood groups in South China. The established reference intervals specific to ABO blood type, sex, and age may improve clinical decisions based on coagulation tests.

Heterogenous impairment of α cell function in type 2 diabetes is linked to cell maturation state.

In diabetes, glucagon secretion from pancreatic α cells is dysregulated. The underlying mechanisms, and whether dysfunction occurs uniformly among cells, remain unclear. We examined α cells from human donors and mice using electrophysiological, transcriptomic, and computational approaches. Rising glucose suppresses α cell exocytosis by reducing P/Q-type Ca2+ channel activity, and this is disrupted in type 2 diabetes (T2D). Upon high-fat feeding of mice, α cells shift toward a "ß cell-like" electrophysiological profile in concert with indications of impaired identity. In human α cells we identified links between cell membrane properties and cell surface signaling receptors, mitochondrial respiratory chain complex assembly, and cell maturation. Cell-type classification using machine learning of electrophysiology data demonstrated a heterogenous loss of "electrophysiologic identity" in α cells from donors with type 2 diabetes. Indeed, a subset of α cells with impaired exocytosis is defined by an enrichment in progenitor and lineage markers and upregulation of an immature transcriptomic phenotype, suggesting important links between α cell maturation state and dysfunction.

Cryopreservation and post-thaw characterization of dissociated human islet cells.

The objective of this study is to optimize the cryopreservation of dissociated islet cells and obtain functional cells that can be used in single-cell transcriptome studies on the pathology and treatment of diabetes. Using an iterative graded freezing approach we obtained viable cells after cooling in 10% dimethyl sulfoxide and 6% hydroxyethyl starch at 1°C/min to -40°C, storage in liquid nitrogen, rapid thaw, and removal of cryoprotectants by serial dilution. The expression of epithelial cell adhesion molecule declined immediately after thaw, but recovered after overnight incubation, while that of an endocrine cell marker (HPi2) remained high after cryopreservation. Patch-clamp electrophysiology revealed differences in channel activities and exocytosis of various islet cell types; however, exocytotic responses, and the biophysical properties of voltage-gated Na+ and Ca2+ channels, are sustained after cryopreservation. Single-cell RNA sequencing indicates that overall transcriptome and crucial exocytosis genes are comparable between fresh and cryopreserved dispersed human islet cells. Thus, we report an optimized procedure for cryopreserving dispersed islet cells that maintained their membrane integrity, along with their molecular and functional phenotypes. Our findings will not only provide a ready source of cells for investigating cellular mechanisms in diabetes but also for bio-engineering pseudo-islets and islet sheets for modeling studies and potential transplant applications.