Genetic Modulation of RNA Splicing with a CRISPR-Guided Cytidine Deaminase.

RNA splicing is a critical mechanism by which to modify transcriptome, and its dysregulation is the underlying cause of many human diseases. It remains challenging, however, to genetically modulate a splicing event in its native context. Here, we demonstrate that a CRISPR-guided cytidine deaminase (i.e., targeted-AID mediated mutagenesis [TAM]) can efficiently modulate various forms of mRNA splicing. By converting invariant guanines to adenines at either 5' or 3' splice sites (SS), TAM induces exon skipping, activation of alternative SS, switching between mutually exclusive exons, or targeted intron retention. Conversely, TAM promotes downstream exon inclusion by mutating cytidines into thymines at the polypyrimidine tract. Applying this approach, we genetically restored the open reading frame and dystrophin function of a mutant DMD gene in patient-derived induced pluripotent stem cells (iPSCs). Thus, the CRISPR-guided cytidine deaminase provides a versatile genetic platform to modulate RNA splicing and to correct mutations associated with aberrant splicing in human diseases.

Sprod for de-noising spatially resolved transcriptomics data based on position and image information.

Spatially resolved transcriptomics (SRT) provide gene expression close to, or even superior to, single-cell resolution while retaining the physical locations of sequencing and often also providing matched pathology images. However, SRT expression data suffer from high noise levels, due to the shallow coverage in each sequencing unit and the extra experimental steps required to preserve the locations of sequencing. Fortunately, such noise can be removed by leveraging information from the physical locations of sequencing, and the tissue organization reflected in corresponding pathology images. In this work, we developed Sprod, based on latent graph learning of matched location and imaging data, to impute accurate SRT gene expression. We validated Sprod comprehensively and demonstrated its advantages over previous methods for removing drop-outs in single-cell RNA-sequencing data. We showed that, after imputation by Sprod, differential expression analyses, pathway enrichment and cell-to-cell interaction inferences are more accurate. Overall, we envision de-noising by Sprod to become a key first step towards empowering SRT technologies for biomedical discoveries.

Dapagliflozin attenuates LPS-induced myocardial injury by reducing ferroptosis.

Septic cardiomyopathy is a severe cardiovascular disease with a poor prognosis. Previous studies have reported the involvement of ferroptosis in the pathogenesis of septic cardiomyopathy. SGLT2 inhibitors such as dapagliflozin have been demonstrated to improve ischemia-reperfusion injury by alleviating ferroptosis in cardiomyocyte. However, the role of dapagliflozin in sepsis remains unclear. Therefore, our study aims to investigate the therapeutic effects of dapagliflozin on LPS-induced septic cardiomyopathy. Our results indicate that dapagliflozin improved cardiac function in septic cardiomyopathy experimental mice. Mechanistically, dapagliflozin works by inhibiting the translation of key proteins involved in ferroptosis, such as GPX4, FTH1, and SLC7A11. It also reduces the transcription of lipid peroxidation-related mRNAs, including PTGS2 and ACSL4, as well as iron metabolism genes TFRC and HMOX1.

Characterization of the gut microbiota in polycystic ovary syndrome with dyslipidemia.

BACKGROUND: Polycystic ovary syndrome (PCOS) is an endocrinopathy in childbearing-age females which can cause many complications, such as diabetes, obesity, and dyslipidemia. The metabolic disorders in patients with PCOS were linked to gut microbial dysbiosis. However, the correlation between the gut microbial community and dyslipidemia in PCOS remains unillustrated. Our study elucidated the different gut microbiota in patients with PCOS and dyslipidemia (PCOS.D) compared to those with only PCOS and healthy women. RESULTS: In total, 18 patients with PCOS, 16 healthy females, and 18 patients with PCOS.D were enrolled. The 16 S rRNA sequencing in V3-V4 region was utilized for identifying the gut microbiota, which analyzes species annotation, community diversity, and community functions. Our results showed that the ß diversity of gut microbiota did not differ significantly among the three groups. Regarding gut microbiota dysbiosis, patients with PCOS showed a decreased abundance of Proteobacteria, and patients with PCOS.D showed an increased abundance of Bacteroidota compared to other groups. With respect to the gut microbial imbalance at genus level, the PCOS.D group showed a higher abundance of Clostridium_sensu_stricto_1 compared to other two groups. Furthermore, the abundances of Faecalibacterium and Holdemanella were lower in the PCOS.D than those in the PCOS group. Several genera, including Faecalibacterium and Holdemanella, were negatively correlated with the lipid profiles. Pseudomonas was negatively correlated with luteinizing hormone levels. Using PICRUSt analysis, the gut microbiota community functions suggested that certain metabolic pathways (e.g., amino acids, glycolysis, and lipid) were altered in PCOS.D patients as compared to those in PCOS patients. CONCLUSIONS: The gut microbiota characterizations in patients with PCOS.D differ from those in patients with PCOS and controls, and those might also be related to clinical parameters. This may have the potential to become an alternative therapy to regulate the clinical lipid levels of patients with PCOS in the future.

Effects of SARS-CoV-2 infection during ovarian stimulation on ART outcomes.

RESEARCH QUESTION: Does severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection during ovarian stimulation affect assisted reproductive technology outcomes? DESIGN: This retrospective cohort study conducted at the Reproductive Medicine Centre of The First Affiliated Hospital of Anhui Medical University aimed to assess the effects of acute SARS-CoV-2 infection during IVF on treatment outcomes and the reproductive system. The study included 151 treatment cycles involving couples with coronavirus disease 2019 (COVID-19) during ovarian stimulation, along with 224 cycles of non-infected couples as a control group. Clinical characteristics and laboratory parameters were analysed, including total gonadotrophin dosage, duration of ovarian stimulation, number of oocytes retrieved, fertilization method, fertilization rate, and number of blastocyst embryos available. Forty-six follicular fluid samples, 38 semen samples and 78 embryo culture medium samples from patients with COVID-19 were tested for SARS-CoV-2 RNA using reverse transcription polymerase chain reaction assay. RESULTS: The treatment and control groups showed similar cycle characteristics, including fertilization method, total gonadotrophin dosage and duration of ovarian stimulation. The mean number of oocytes retrieved per cycle and rate of mature oocytes in intracytoplasmic sperm injection cycles were comparable. No significant difference was observed in the total number of blastocyst embryos available between the groups. Furthermore, no SARS-CoV-2 RNA was detected in any of the samples of patients with COVID-19. CONCLUSIONS: In conclusion, acute SARS-CoV-2 infection during ovarian stimulation does not have a significant impact on IVF treatment outcomes. Additionally, no risk to the reproductive system was observed in patients infected with SARS-CoV-2. Therefore, individuals with asymptomatic or mild COVID-19 can safely continue IVF treatment. Future research is needed to investigate the long-term effects of COVID-19 on fertility and reproductive outcomes.

SEPA-1 mediates the specific recognition and degradation of P granule components by autophagy in C. elegans.

How autophagy, an evolutionarily conserved intracellular catabolic system for bulk degradation, selectively degrades protein aggregates is poorly understood. Here, we show that several maternally derived germ P granule components are selectively eliminated by autophagy in somatic cells during C. elegans embryogenesis. The activity of sepa-1 is required for the degradation of these P granule components and for their accumulation into aggregates, termed PGL granules, in autophagy mutants. SEPA-1 forms protein aggregates and is also a preferential target of autophagy. SEPA-1 directly binds to the P granule component PGL-3 and also to the autophagy protein LGG-1/Atg8. SEPA-1 aggregates consistently colocalize with PGL granules and with LGG-1 puncta. Thus, SEPA-1 functions as a bridging molecule in mediating the specific recognition and degradation of P granule components by autophagy. Our study reveals a mechanism for preferential degradation of protein aggregates by autophagy and emphasizes the physiological significance of selective autophagy during animal development.

A low-cost process for complete utilization of bauxite residue.

Cost-effective treatment or even valorization of the bauxite residue (red mud) from the alumina industry is in demand to improve their environmental and economic liabilities. This study proposes a strategy that provides a near-complete conversion of bauxite residue to valuable products. The first step involves dilute acid leaching, which allowed the fractionation of raw residues into (1) an aqueous fraction rich in silica and aluminium and (2) a solid residue rich in iron, titanium and rare earth elements. For the proposed process, 91% of the original silicon, 67% of the aluminium, 78% of the scandium and 69% of the cerium were recovered. The initial cost evaluation suggested that this approach is profitable with a gross margin of 167 $US per tonne. This "Residue2Product" approach should be considered for large-scale practices as one of the most economical and sustainable solutions to this environmental and economic liability for the alumina industry.

Bi-allelic Loss-of-function Variants in CFAP58 Cause Flagellar Axoneme and Mitochondrial Sheath Defects and Asthenoteratozoospermia in Humans and Mice.

Multiple morphological abnormalities of the sperm flagella (MMAF) is a severe form of asthenoteratozoospermia. Although recent studies have revealed several MMAF-associated genes and demonstrated MMAF to be a genetically heterogeneous disease, at least one-third of the cases are still not well understood for their etiology. Here, we identified bi-allelic loss-of-function variants in CFAP58 by using whole-exome sequencing in five (5.6%) unrelated individuals from a cohort of 90 MMAF-affected Chinese men. Each of the men harboring bi-allelic CFAP58 variants presented typical MMAF phenotypes. Transmission electron microscopy demonstrated striking flagellar defects with axonemal and mitochondrial sheath malformations. CFAP58 is predominantly expressed in the testis and encodes a cilia- and flagella-associated protein. Immunofluorescence assays showed that CFAP58 localized at the entire flagella of control sperm and predominantly concentrated in the mid-piece. Immunoblotting and immunofluorescence assays showed that the abundances of axoneme ultrastructure markers SPAG6 and SPEF2 and a mitochondrial sheath protein, HSP60, were significantly reduced in the spermatozoa from men harboring bi-allelic CFAP58 variants. We generated Cfap58-knockout mice via CRISPR/Cas9 technology. The male mice were infertile and presented with severe flagellar defects, consistent with the sperm phenotypes in MMAF-affected men. Overall, our findings in humans and mice strongly suggest that CFAP58 plays a vital role in sperm flagellogenesis and demonstrate that bi-allelic loss-of-function variants in CFAP58 can cause axoneme and peri-axoneme malformations leading to male infertility. This study provides crucial insights for understanding and counseling of MMAF-associated asthenoteratozoospermia.

Soil Acidification Under Long-Term N Addition Decreases the Diversity of Soil Bacteria and Fungi and Changes Their Community Composition in a Semiarid Grassland.

Soil microorganisms play key roles in terrestrial biogeochemical cycles and ecosystem functions. However, few studies address how long-term nitrogen (N) addition gradients impact soil bacterial and fungal diversity and community composition simultaneously. Here, we investigated soil bacterial and fungal diversity and community composition based on a long-term (17 years) N addition gradient experiment (six levels: 0, 2, 4, 8, 16, 32 gN m-2 year-1) in temperate grassland, using the high-throughput Illumina MiSeq sequencing. Results showed that both soil bacterial and fungal alpha diversity responded nonlinearly to the N input gradient and reduced drastically when the N addition rate reached 32 g N m-2 year-1. The relative abundance of soil bacterial phyla Proteobacteria increased and Acidobacteria decreased significantly with increasing N level. In addition, the relative abundance of bacterial functional groups associated with aerobic ammonia oxidation, aerobic nitrite oxidation, nitrification, respiration of sulfate and sulfur compounds, and chitinolysis significantly decreased under the highest N addition treatment. For soil fungi, the relative abundance of Ascomycota increased linearly along the N enrichment gradient. These results suggest that changes in soil microbial community composition under elevated N do not always support the copiotrophic-oligotrophic hypothesis, and some certain functional bacteria would not simply be controlled by soil nutrients. Further analysis illustrated that reduced soil pH under N addition was the main factor driving variations in soil microbial diversity and community structure in this grassland. Our findings highlight the consistently nonlinear responses of soil bacterial and fungal diversity to increasing N input and the significant effects of soil acidification on soil microbial communities, which can be helpful for the prediction of underground ecosystem processes in light of future rising N deposition.

Complete genome sequence of a novel mycovirus from Pleurotus citrinopileatus.

The complete genome sequence of a novel single-stranded [+ ssRNA] positive-sense (+) RNA mycovirus, designated as "Pleurotus citrinopileatus ourmiavirus 1" (PcOV1), isolated from Pleurotus citrinopileatus strain CCMJ2141, was determined. The complete genome of PcOV1 is composed of 2,535 nucleotides. It contains a single open reading frame (ORF), which encodes a protein of 657 amino acids (aa) containing conserved domains of an RNA-dependent RNA polymerase (RdRp). Phylogenetic analysis based on RdRp sequences revealed that PcOV1 is a new member of the genus Ourmiavirus in the family Botourmiaviridae. This is the first virus from P. citrinopileatus to be characterized.

Remote ischaemic preconditioning versus no remote ischaemic preconditioning for vascular and endovascular surgical procedures.

BACKGROUND: Despite advances in perioperative care, elective major vascular surgical procedures still carry a significant risk of morbidity and mortality. Remote ischaemic preconditioning (RIPC) is the temporary blocking of blood flow to vascular beds remote from those targeted by surgery. It has the potential to provide local tissue protection from further prolonged periods of ischaemia. However, the efficacy and safety of RIPC in people undergoing major vascular surgery remain unknown. This is an update of a review published in 2011.  OBJECTIVES: To assess the benefits and harms of RIPC versus no RIPC in people undergoing elective major vascular and endovascular surgery. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov to 1 April 2022. SELECTION CRITERIA: We included all randomised controlled trials that evaluated the role of RIPC in reducing perioperative mortality and morbidities in people undergoing elective major vascular or endovascular surgery. DATA COLLECTION AND ANALYSIS: We collected data on the characteristics of the trial, methodological quality, and the remote ischaemic preconditioning stimulus used. Our primary outcome was perioperative mortality, and secondary outcomes included myocardial infarction, renal impairment, stroke, hospital stay, limb loss, and operating time or total anaesthetic time. We analysed the data using random-effects models. For each outcome, we calculated the risk ratio (RR) or mean difference (MD) with a 95% confidence interval (CI) based on an intention-to-treat analysis. In addition, we used GRADE to assess the certainty of the evidence for each outcome. MAIN RESULTS: We included 14 trials which randomised a total of 1295 participants (age range: 64.5 to 76 years; 84% male; study periods ranged from 2003 to 2019). In general, the included studies were at low to unclear risk of bias for most risk of bias domains. The certainty of evidence of main outcomes was moderate due to imprecision of results, moderate heterogeneity, or possible publication bias. We found that RIPC made no clear difference in perioperative mortality compared with no RIPC (RR 1.41, 95% CI 0.59 to 3.40; I2 = 0%; 10 studies, 965 participants; moderate-certainty evidence). Similarly, we found no clear difference between the two groups for myocardial infarction (RR 0.82, 95% CI 0.49 to 1.40; I2 = 7%; 11 studies, 1001 participants; moderate-certainty evidence), renal impairment (RR 1.07, 95% CI 0.62 to 1.86; I2 = 40%; 12 studies, 1054 participants; moderate-certainty evidence), stroke (RR 0.33, 95% CI 0.04 to 3.15; I2 = 0%; 4 studies, 392 participants; moderate-certainty evidence), limb loss (RR 0.74, 95% CI 0.05 to 10.61; I2 = 32%; 3 studies, 322 participants; low-certainty evidence), hospital stay (MD -0.94 day, 95% CI -1.95 to 0.07; I2 = 17%; 7 studies, 569 participants; moderate-certainty evidence), and operating time or total anaesthetic time (MD 5.76 minutes, 95% CI -3.25 to 14.76; I2 = 44%; 10 studies, 803 participants; moderate-certainty evidence).  AUTHORS' CONCLUSIONS: Overall, compared with no RIPC, RIPC probably leads to little or no difference in perioperative mortality, myocardial infarction, renal impairment, stroke, hospital stay, and operating time, and may lead to little or no difference in limb loss in people undergoing elective major vascular and endovascular surgery. Adequately powered and designed randomised studies are needed, focusing in particular on the clinical endpoints and patient-centred outcomes.

Uterine torsion complicated by severe placental abruption in the second trimester: a case report and literature review.

BACKGROUND: Uterine torsion is a rare obstetric event that can occur during pregnancy and is difficult to diagnose. Its occurrence may lead to serious adverse pregnancy outcomes. CASE INTRODUCTION: The patient was a 33-year-old woman at 30+ 5 weeks' gestation with a singleton pregnancy. The pregnancy course, including fetal growth, and prenatal examinations were regular. Except for a small amount of vaginal bleeding in early pregnancy and treatment with progesterone, there were no prenatal abnormalities, and the patient denied any trauma or sexual history. The patient was admitted to the emergency department with persistent severe pain in the lower abdomen and slight vaginal bleeding during night sleep. Abdominal pain started two hours prior to admission and was accompanied by nausea, vomiting, and dizziness. Examination revealed positive abdominal tenderness, high uterine tone, and no significant intermittent period of uterine contractions, and measurement of the fetal heart rate by means of the nonstress test revealed a rate of 60 beats per minute. Therefore, placental abruption was highly suspected. Subsequently, an emergency cesarean section was performed under general anesthesia. The newborn boy, with Apgar scores of 0-3-4 after birth and weighing 1880 g, was transferred to the neonatal intensive care unit (NICU) and died two days later due to ineffective rescue. After the uterine incision was sutured, the examination revealed that the uterine incision was located on the posterior wall of the uterus, and the uterus was twisted 180° to the right. The diagnosis after cesarean section was 180° uterine torsion to the right, severe placental abruption, and severe neonatal asphyxia. On the fifth day after surgery, the patient recovered and was discharged from the hospital. CONCLUSIONS: Posterior uterine incision cesarean section may be performed in unexpected circumstances and is also feasible as a safe option for resetting if torsion is not complete. Abdominal pain during pregnancy is less likely to be diagnosed as uterine torsion, which often leads to premature birth, fetal asphyxia, placental abruption, and even perinatal death. Therefore, for abdominal pain during pregnancy, obstetricians should consider the possibility of uterine torsion.

The mediating role of HbA1c in the association between elevated low-density lipoprotein cholesterol levels and diabetic peripheral neuropathy in patients with type 2 diabetes mellitus.

BACKGROUND: Increased levels of low-density lipoprotein cholesterol (LDL-C) have been identified as one potential risk factor for diabetic peripheral neuropathy (DPN) in patients. The current study seeks to clarify the link between LDL-C, hyperglycemia, and DPN in patients with type 2 diabetes mellitus (T2DM). METHODS: Here, a total of 120 T2DM individuals were recruited. These volunteers with T2DM were divided into 2 groups, based on the presence or absence of peripheral neuropathy. Additionally, their baseline characteristics were compared. Association among LDL-C and glycosylated hemoglobin (HbA1c) levels and DPN, particularly with respect to specific nerve conduction velocity were analyzed. To identify factors influencing DPN, regression was performed. Furthermore, mediation analysis was employed to evaluate the indirect, direct and total effects of LDL-C on specific nerve conduction velocity, with HbA1c serving as a mediator. RESULTS: Compared to 55 patients without DPN, 65 patients with DPN demonstrated elevated levels of LDL-C and HbA1c. Both LDL-C and HbA1c have been found to be associated with reduced the motor fiber conduction velocities of Ulnar (or the Common peroneal) nerve in diabetic patients. HbA1c is one of the known risk factors for DPN in individuals with T2DM. Further mediation analysis revealed that the effect of LDL-C on the Ulnar (or the Common peroneal) nerve motor fiber conduction velocities are fully mediated by HbA1c in patients with T2DM. CONCLUSIONS: The impact of elevated LDL-C levels upon the Ulnar (or the Common peroneal) nerve motor fiber conduction velocities in patients with T2DM was found to be entirely mediated by increased HbA1c levels.

The mediating effect of psychological resilience between social support and anxiety/depression in people living with HIV/AIDS-a study from China.

Objective To understand the relationship between psychological resilience in social support and anxiety/depression in people living with HIV/AIDS and to verify whether there is a mediating effect. Methods The questionnaire was administered to 161 people living with HIV/AIDS in a hospital. The questionnaire contained a general questionnaire, the Hospital Anxiety and Depression Scale (HADS), the Psychological Resilience Inventory (CD-RICS), and the Social Collaborative Support Scale (PSSS), and Pearson correlation analyses were used to explore the correlation between the factors and anxiety/depression, stratified linear regression analyses were used to validate the mediation model, and the bootstrap method was used to test for mediating effects. Results Anxiety was negatively correlated with psychological resilience and social support (r=-0.232, P < 0.01; r=-0.293, P < 0.01); depression was negatively correlated with psychological resilience and social support (r=-0.382, P < 0.01; r=-0.482, P < 0.01); there was a mediation effect model of social support between psychological resilience and anxiety/depression; psychological resilience played a fully mediating role in social support and anxiety/depression, with an effect contribution of 68.42%/59.34% and a 95% CI(-0.256~-0.036)/(-0.341 to~-0.106). Conclusion Psychological resilience plays a complete mediating effect between social support and anxiety/depression. It is recommended that more channels of social support be provided to patients with HIV/AIDS, thereby enhancing their psychological resilience and reducing anxiety/depression levels.

Novel mutations in DNAH17 cause sperm flagellum defects and their influence on ICSI outcome.

PURPOSE: To identify new mutations in DNAH17 that cause male infertility and analyze intracytoplasmic sperm injection (ICSI) outcomes in patients with DNAH17 mutations. METHODS: A total of five cases of new DNAH17 mutations exhibiting the multiple morphological abnormalities of the sperm flagella (MMAF) phenotype were identified through semen analysis and genetic testing. They were recruited at our reproductive medicine center from September 2018 to July 2022. Information on DNAH17 genetic mutations and ICSI outcomes was systematically explored following a literature review. RESULTS: Three novel compound mutations in DNAH17 were identified in patients with male infertility caused by MMAF. This study and previous publications included 21 patients with DNAH17 mutations. DNAH17 has been associated with asthenozoospermia and male infertility, but different types of DNAH17 variants appear to be involved in different sperm phenotypes. In 11 couples of infertile patients with DNAH17 mutations, there were 17 ICSI cycles and 13 embryo transplantation cycles. Only three men with DNAH17 variants ultimately achieved clinical pregnancy with their partners through ICSI combined with assisted oocyte activation (AOA). CONCLUSIONS: Loss-of-function mutations in DNAH17 can lead to severe sperm flagellum defects and male infertility. Patients with MMAF-harboring DNAH17 mutations generally have worse pregnancy outcomes following ICSI. ICSI combined with AOA may improve the outcome of assisted reproductive techniques (ARTs) for men with DNAH17 variants.

Does False Lumen Thrombosis Lead to Better Outcomes in Patients with Aortic Dissection: A Meta-Analysis and Systematic Review.

OBJECTIVES: For a long time, the association of the false lumen status and the outcomes of patients suffering from aortic dissection has been unclear, so this review article aims to study whether the unobstructed of the false lumen is related to the outcome of patients suffering from aortic dissection. METHODS: We performed this systematic review and meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta Analyzes Protocols (PRISMA) statement 2009 and registered with PROSPERO (CRD42022381869). We searched PubMed, the Cochrane library, Web of Science and Embase to collect potential studies. The Newcastle-Ottawa Scale was used to assess the quality of the included studies. The main outcome is long-term survival. Data included in the study were summarized using the risk ratio or mean difference and 95% confidence interval. RESULTS: There were 16 trials, 2829 patients in total, with a mean age of 62.1 years. Compared with completely thrombosed false lumen, patent group has better long-term survival (risk ratio (RR), 0.88; 95% CI, 0.79 to 0.97; p = 0.01; I2 = 58%) and smaller yearly aortic growth rate (mean difference (MD), 1.03; 95% CI, 0.23 to 1.82; p = 0.01; I2 = 98%). In addition, patients with a patent false lumen had a lower risk of aortic event (RR, 0.81; 95% CI, 0.68 to 0.97; p = 0.02; I2 = 37%), but higher risk of aortic rupture (RR, 7.02; 95% CI, 2.55 to 19.3; p = 0.0002; I2 = 0) and hospital death (RR, 2.72; 95% CI, 1.45 to 5.08; p = 0.002; I2 = 0). CONCLUSION: Completely thrombosed of the false lumen is more beneficial to the long-term survival of patients with aortic dissection. And the risk of aortic rupture and hospital death in patients with patent false lumen is 7 times and 3 times that of patients with complete thrombosed false lumen. It is expected to provide individualized medical care for different types of patients according to different false lumen status to minimize death and related complications.

Hypoxia drives transient site-specific copy gain and drug-resistant gene expression.

Copy number heterogeneity is a prominent feature within tumors. The molecular basis for this heterogeneity remains poorly characterized. Here, we demonstrate that hypoxia induces transient site-specific copy gains (TSSGs) in primary, nontransformed, and transformed human cells. Hypoxia-driven copy gains are not dependent on HIF1α or HIF2α; however, they are dependent on the KDM4A histone demethylase and are blocked by inhibition of KDM4A with a small molecule or the natural metabolite succinate. Furthermore, this response is conserved at a syntenic region in zebrafish cells. Regions with site-specific copy gain are also enriched for amplifications in hypoxic primary tumors. These tumors exhibited amplification and overexpression of the drug resistance gene CKS1B, which we recapitulated in hypoxic breast cancer cells. Our results demonstrate that hypoxia provides a biological stimulus to create transient site-specific copy alterations that could result in heterogeneity within tumors and cell populations. These findings have major implications in our understanding of copy number heterogeneity and the emergence of drug resistance genes in cancer.

Barriers and facilitators to pressure injury prevention in hospitals: A mixed methods systematic review.

OBJECTIVE: To systematically synthesize research evidence on barriers and facilitators to pressure injury prevention in hospital settings. METHODS: A systematic literature review of quantitative, qualitative, and mixed methods research was undertaken using PubMed, MEDLINE, Embase, CINAHL, and Cochrane Library. Studies that reported barriers or/and facilitators to pressure injury prevention in the acute care settings and published in English from 2008 to 2022 were included. Studies were excluded if they were conducted in residential care facilities and nursing homes, or other long-term community care settings. Two authors independently screened articles against the inclusion and exclusion criteria. Quality appraisal was conducted by two authors by using the Mixed Methods Appraisal Tool. Reported results were mapped to the Theoretical Domains Framework to identify the barriers and facilitators to pressure injury prevention. RESULTS: A total of 78 studies were included. There were 65 quantitative studies, 11 qualitative studies, and two mix-methods studies. The most salient Theoretical Domains Framework domains identified in this review were "Knowledge", "Skills", "Environmental Context and Resources", "Optimism", "Social/Professional Role and Identity", and "Social influences". CONCLUSION: The barriers and facilitators to pressure injury prevention in hospital settings identified in this systematic review were diverse, and included issues at both individual and organizational level. Healthcare organizations can address the barriers and facilitators from the influential Theoretical Domains Framework domains. Future research is required to investigate the effectiveness of behaviour change interventions that specifically target these barriers and facilitators to pressure injury prevention.

Novel biallelic mutations in SLC26A8 cause severe asthenozoospermia in humans owing to midpiece defects: Insights into a putative dominant genetic disease.

To investigate the genetic cause of male infertility characterized by severe asthenozoospermia, two unrelated infertile men with severe asthenozoospermia from nonconsanguineous Chinese families were enrolled, and whole exome sequencing were performed to identify the potential pathogenic mutations. Novel compound heterozygous mutations (NK062 III-1: c.290T>C, p.Leu97Pro; c.1664delT, p.Ile555Thrfs*11/NK038 III-1: c.212G>T, p.Arg71Leu; c.290T>C, p.Leu97Pro) in SLC26A8 were identified. All mutations were inherited from their heterozygous parents and are predicted to be disease-causing by sorts intolerant from tolerant, PolyPhen-2, Mutation Taster, and Combined Annotation Dependent Depletion. In silico mutant SLC26A8 models predict that mutations p.Leu97Pro and p.Arg71Leu cause changes in the α-helix, which may result in functional defects in the protein. Notably, heterozygous male carriers of each mutation in both families were able to reproduce naturally, which is inconsistent with previous reports. Ultrastructural analysis revealed severe asthenozoospermia associated with absence of the mitochondrial sheath and annulus in spermatozoa from both the probands, and both structural defects were verified by HSP60 and SEPT4 immunofluorescence analysis. SLC26A8 levels were significantly reduced in spermatozoa from patients harboring biallelic SLC26A8 mutations, and both patients achieved good prognosis following intracytoplasmic sperm injection. Our findings indicate that mutations in SLC26A8 could manifest as a recessive genetic cause of severe asthenozoospermia and male infertility.

CRISPR/Cas9-mediated ß-globin gene knockout in rabbits recapitulates human ß-thalassemia.

ß-thalassemia, an autosomal recessive blood disorder that reduces the production of hemoglobin, is majorly caused by the point mutation of the HBB gene resulting in reduced or absent ß-globin chains of the hemoglobin tetramer. Animal models recapitulating both the phenotype and genotype of human disease are valuable in the exploration of pathophysiology and for in vivo evaluation of novel therapeutic treatments. The docile temperament, short vital cycles, and low cost of rabbits make them an attractive animal model. However, ß-thalassemia rabbit models are currently unavailable. Here, using CRISPR/Cas9-mediated genome editing, we point mutated the rabbit ß-globin gene HBB2 with high efficiency and generated a ß-thalassemia rabbit model. Hematological and histological analyses demonstrated that the genotypic mosaic F0 displayed a mild phenotype of anemia, and the heterozygous F1 exhibited typical characteristics of ß-thalassemia. Whole-blood transcriptome analysis revealed that the gene expression was altered in HBB2-targeted when compared with WT rabbits. And the highly expressed genes in HBB2-targeted rabbits were enriched in lipid and iron metabolism, innate immunity, and hematopoietic processes. In conclusion, using CRISPR-mediated HBB2 knockout, we have created a ß-thalassemia rabbit model that accurately recapitulates the human disease phenotype. We believe this tool will be valuable in advancing the investigation of pathogenesis and novel therapeutic targets of ß-thalassemia and associated complications.