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Cell-to-cell mitochondrial transfer has recently been shown to play a role in maintaining physiological functions of cell. We previously illustrated that mitochondrial transfer within osteocyte dendritic network regulates bone tissue homeostasis. However, the mechanism of triggering this process has not been explored. Here, we showed that stressed osteocytes in mice release adenosine diphosphate (ADP), resulting in triggering mitochondrial transfer from healthy osteocytes to restore the oxygen consumption rate (OCR) and to alleviate reactive oxygen species accumulation. Furthermore, we identified that P2Y2 and P2Y6 transduced the ADP signal to regulate osteocyte mitochondrial transfer. We showed that mitochondrial metabolism is impaired in aged osteocytes, and there were more extracellular nucleotides release into the matrix in aged cortical bone due to compromised membrane integrity. Conditioned medium from aged osteocytes triggered mitochondrial transfer between osteocytes to enhance the energy metabolism. Together, using osteocyte as an example, this study showed new insights into how extracellular ADP triggers healthy cells to rescue energy metabolism crisis in stressed cells via mitochondrial transfer in tissue homeostasis.
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Difosfato de Adenosina , Homeostase , Mitocôndrias , Osteócitos , Animais , Osteócitos/metabolismo , Mitocôndrias/metabolismo , Camundongos , Difosfato de Adenosina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Consumo de Oxigênio , Metabolismo Energético , Camundongos Endogâmicos C57BL , Estresse FisiológicoRESUMO
Despite the various strategies for achieving metal-nitrogen-carbon (M-N-C) single-atom catalysts (SACs) with different microenvironments for electrochemical carbon dioxide reduction reaction (CO2RR), the synthesis-structure-performance correlation remains elusive due to the lack of well-controlled synthetic approaches. Here, we employed Ni nanoparticles as starting materials for the direct synthesis of nickel (Ni) SACs in one spot through harvesting the interaction between metallic Ni and N atoms in the precursor during the chemical vapor deposition growth of hierarchical N-doped graphene fibers. By combining with first-principle calculations, we found that the Ni-N configuration is closely correlated to the N contents in the precursor, in which the acetonitrile with a high N/C ratio favors the formation of Ni-N3, while the pyridine with a low N/C ratio is more likely to promote the evolution of Ni-N2. Moreover, we revealed that the presence of N favors the formation of H-terminated edge of sp2 carbon and consequently leads to the formation of graphene fibers consisting of vertically stacked graphene flakes, instead of the traditional growth of carbon nanotubes on Ni nanoparticles. With a high capability in balancing the *COOH formation and *CO desorption, the as-prepared hierarchical N-doped graphene nanofibers with Ni-N3 sites exhibit a superior CO2RR performance compared to that with Ni-N2 and Ni-N4 ones.
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The contractile vacuole complex (CVC) is a dynamic and morphologically complex membrane organelle, comprising a large vesicle (bladder) linked with a tubular reticulum (spongiome). CVCs provide key osmoregulatory roles across diverse eukaryotic lineages, but probing the mechanisms underlying their structure and function is hampered by the limited tools available for in vivo analysis. In the experimentally tractable ciliate Tetrahymena thermophila, we describe four proteins that, as endogenously tagged constructs, localize specifically to distinct CVC zones. The DOPEY homolog Dop1p and the CORVET subunit Vps8Dp localize both to the bladder and spongiome but with different local distributions that are sensitive to osmotic perturbation, whereas the lipid scramblase Scr7p colocalizes with Vps8Dp. The H+-ATPase subunit Vma4 is spongiome specific. The live imaging permitted by these probes revealed dynamics at multiple scales including rapid exchange of CVC-localized and soluble protein pools versus lateral diffusion in the spongiome, spongiome extension and branching, and CVC formation during mitosis. Although the association with DOP1 and VPS8D implicate the CVC in endosomal trafficking, both the bladder and spongiome might be isolated from bulk endocytic input.
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Tetrahymena thermophila , Vacúolos , Vacúolos/metabolismo , Endossomos , Proteínas/metabolismo , MitoseRESUMO
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide, and the development of novel therapeutic strategies for HNSCC requires a profound understanding of tumor cells and the tumor microenvironment (TME). Additionally, HNSCC has a poor prognosis, necessitating the use of genetic markers for predicting clinical outcomes in HNSCC. In this study, we performed single-cell sequencing analysis on tumor tissues from seven HNSCC patients, along with one adjacent normal tissue. Firstly, the analysis of epithelial cell clusters revealed two clusters of malignant epithelial cells, characterized by unique gene expression patterns and dysregulated signaling pathways compared to normal epithelial cells. Secondly, the examination of the TME unveiled extensive crosstalk between fibroblasts and malignant epithelial cells, potentially mediated through ligand-receptor interactions such as COL1A1-SDC1, COL1A1-CD44, and COL1A2-SDC1. Furthermore, transcriptional heterogeneity was observed in immune cells present in the TME, including macrophages and dendritic cells. Finally, leveraging the gene expression profiles of malignant epithelial cells, we developed a prognostic model comprising six genes, which we validated using two independent datasets. These findings shed light on the heterogeneity within HNSCC tumors and the intricate interplay between malignant cells and the TME. Importantly, the developed prognostic model demonstrates high efficacy in predicting the survival outcomes of HNSCC patients.
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Carcinoma , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Prognóstico , Neoplasias de Cabeça e Pescoço/genética , Células Epiteliais , Microambiente Tumoral/genéticaRESUMO
Silicon (Si) is considered a promising commercial material for the next-generation of high-energy density lithium-ion battery (LIB) due to its high theoretical capacity. However, the severe volume changes and the poor conductivity hinder the practical application of Si anode. Herein, a novel core-shell heterostructure, Si as the core and V3 O4 @C as the shell (Si@V3 O4 @C), is proposed by a facile solvothermal reaction. Theoretical simulations have shown that the in-situ-formed V3 O4 layer facilitates the rapid Li+ diffusion and lowers the energy barrier of Li transport from the carbon shell to the inner core. The 3D network structure constructed by amorphous carbon can effectively improve electronic conductivity and structural stability. Benefiting from the rationally designed structure, the optimized Si@V3 O4 @C electrode exhibits an excellent cycling stability of 1061.1 mAh g-1 at 0.5 A g-1 over 700 cycles (capacity retention of 70.0%) with an average Coulombic efficiency of 99.3%. In addition, the Si@V3 O4 @C||LiFePO4 full cell shows a superior capacity retention of 78.7% after 130 cycles at 0.5 C. This study opens a novel way for designing high-performance silicon anode for advanced LIBs.
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The efficient removal of radioactive uranium from aqueous solution is of great significance for the safe and sustainable development of nuclear power. An ultrathin 2D metal-organic framework (MOF) nanosheet with cavity structures was elaborately fabricated based on a calix[4]arene ligand. Incorporating the permanent cavity structures on MOF nanosheet can fully utilize its structural characteristics of largely exposed surface area and accessible adsorption sites in pollutant removal, achieving ultrafast adsorption kinetics, and the functionalized cavity structure would endow the MOF nanosheets with the ability to achieve preconcentration and extraction of uranium from aqueous solution, affording ultrahigh removal efficiency even in ultra-low concentrations. Thus, more than 97% uranium can be removed from the concentration range of 50-500 µg L-1 within 5 min. Moreover, the 2D nano-material exhibits ultra-high anti-interference ability, which can efficiently remove uranium from groundwater and seawater. The adsorption mechanism was investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) analysis, and density functional theory (DFT) calculations, which revealed that the cavity structure plays an important role in uranium capture. This study not only realizes highly efficient uranium removal from aqueous solution but also opens the door to achieving ultrathin MOF nanosheets with cavity structures, which will greatly expand the applications of MOF nanosheets.
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BACKGROUND: We sought to create a laparoscopic-based model to predict the ability to perform a minimally invasive (MIS) cytoreductive surgery in advanced epithelial ovarian cancer patients who have received neoadjuvant chemotherapy (NACT). METHODS: Fifty women were enrolled in a multi-institutional prospective pilot study (NCT03378128). Each patient underwent laparoscopic evaluation of 43 abdominopelvic sites followed by surgeon dictated surgical approach, either continue MIS or laparotomically. However, if the procedure continued MIS, the placement of a hand-assist port for manual palpation was mandated to emulate a laparotomic approach and all 43 sites were re-evaluated. Sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy were calculated for each site to predict MIS resectability. Each parameter was assigned a numeric value based on the strength of statistical association and a total predictive index score (PIV) was assigned for each patient. Receiver operating characteristic curve analysis was used to assess the ability of the model to predict the MIS approach. RESULTS: Twenty-seven patients (61%) underwent MIS surgery. The following abdominopelvic sites were selected for inclusion in the model: gastrosplenic ligament, rectum, left mesocolon, transverse colon, right colon, cecum, appendix, liver capsule, intrahepatic fossa/gallbladder, ileum/jejunum. Using the PIV, a ROC was generated with an AUC = 0.695. In the final model, a PIV <2 identified patients able to undergo an optimal MIS cytoreductive surgery with an accuracy of 68.2%. The specificity, or the ability to identify patients who would not be able to undergo an optimal MIS interval cytoreductive surgery, was 66.7%. CONCLUSION: This predictive index model may help to guide future inclusion criteria in randomized studies evaluating the MIS approach in advanced epithelial ovarian cancer.
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Carcinoma Epitelial do Ovário , Procedimentos Cirúrgicos de Citorredução , Laparoscopia , Neoplasias Ovarianas , Humanos , Feminino , Procedimentos Cirúrgicos de Citorredução/métodos , Neoplasias Ovarianas/cirurgia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/tratamento farmacológico , Laparoscopia/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Carcinoma Epitelial do Ovário/cirurgia , Carcinoma Epitelial do Ovário/patologia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Projetos Piloto , Terapia Neoadjuvante , Idoso , Adulto , Valor Preditivo dos TestesRESUMO
OBJECTIVE(S): To evaluate whether extended dosing of antibiotics (ABX) after cytoreductive surgery (CRS) with large bowel resection for advanced ovarian cancer is associated with reduced incidence of surgical site infection (SSI) compared to standard intra-operative dosing and evaluate predictors of SSI. METHODS: A retrospective single-institution cohort study was performed in patients with stage III/IV ovarian cancer who underwent CRS from 2009 to 2017. Patients were divided into two cohorts: 1) standard intra-operative dosing ABX and 2) extended post-operative ABX. All ABX dosing was at the surgeon's discretion. The impact of antibiotic duration on SSI and other postoperative outcomes was assessed using univariate and multivariable Cox regression models. RESULTS: In total, 277 patients underwent cytoreductive surgery (CRS) with large bowel resection between 2009 and 2017. Forty-nine percent (n = 137) received standard intra-operative ABX and 50.5% (n = 140) received extended post-operative ABX. Rectosigmoid resection was the most common large bowel resection in the standard ABX (89.9%, n = 124) and extended ABX groups (90.0%, n = 126), respectively. No significant differences existed between age, BMI, hereditary predisposition, or medical comorbidities (p > 0.05). No difference was appreciated in the development of superficial incisional SSI between the standard ABX and extended ABX cohorts (10.9% vs. 12.9%, p = 0.62). Of patients who underwent a transverse colectomy, a larger percentage of patients developed a superficial SSI versus no SSI (21% vs. 6%, p = 0.004). CONCLUSION(S): In this retrospective study of patients with advanced ovarian cancer undergoing CRS with LBR, extended post-operative ABX was not associated with reduced SSI, and prolonged administration of antibiotics should be avoided unless clinically indicated.
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Antibacterianos , Procedimentos Cirúrgicos de Citorredução , Neoplasias Ovarianas , Infecção da Ferida Cirúrgica , Humanos , Feminino , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Estudos Retrospectivos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos de Citorredução/métodos , Procedimentos Cirúrgicos de Citorredução/efeitos adversos , Neoplasias Ovarianas/cirurgia , Antibacterianos/administração & dosagem , Idoso , Antibioticoprofilaxia/métodos , Estudos de Coortes , AdultoRESUMO
Necrotizing enterocolitis (NEC) is a common disorder in premature infants that is characterized by hyperinflammation and severe necrosis in the intestine. The pathogenesis of NEC remains to be elucidated. In this study, we demonstrate that adenosine, a metabolite more abundant in infants than in adults, plays an important role in the prevention of NEC. Administration of adenosine or its analog, adenosine-5'-N-ethyluronamide (NECA), dramatically relieved the severity of NEC in neonatal mice. Meanwhile, adenosine treatment significantly enhanced the immunosuppressive function, antibacterial activity, and migration of myeloid-derived suppressor cells (MDSCs). However, depletion of MDSCs or inhibition of their migration using the CXCR2 inhibitor SB225002 almost completely abrogated the protective effect of adenosine on NEC. Mechanistic studies showed that MDSCs in newborns expressed abundant adenosine receptor A2B (A2BR) that elicits intracellular cAMP signaling and its downstream target NF-κB. Importantly, intestinal tissues from patients with NEC showed significantly lower infiltration of A2BR-positive MDSCs than those from healthy donors. These observations revealed that adenosine-induced MDSCs represent an essential immune axis for intestinal homeostasis in newborns.
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Enterocolite Necrosante , Células Supressoras Mieloides , Adenosina , Animais , Enterocolite Necrosante/tratamento farmacológico , Enterocolite Necrosante/metabolismo , Humanos , Imunossupressores , Recém-Nascido , Camundongos , Células Supressoras Mieloides/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/fisiologiaRESUMO
OBJECTIVE: Ovarian cancer is associated with a high rate of venous thromboembolism. Our objective is to report the incidence of venous thromboembolism in recurrent ovarian cancer, assess the impact on morbidity and mortality, and evaluate predictors of venous thromboembolism. METHODS: A retrospective single institution cohort study was performed. Patients with a diagnosis of recurrent ovarian cancer between 2007 and 2020 and no previous history of venous thromboembolism were identified. Demographic and clinical variables were collected. Univariate and multivariable analyses were performed to identify predictors of venous thromboembolism. RESULTS: Of the 345 patients included in this study, 77 (22.3%) developed a venous thromboembolism. Most (n=56, 72.7%) were actively receiving treatment at the time of diagnosis of venous thromboembolism, of whom 44 (78.6%) had received three or more lines of treatment. In total, 42 (54.5%) were admitted to hospital on diagnosis and one mortality (1.3%) occurred secondary to venous thromboembolism. An intermediate/high risk Khorana score was not predictive of venous thromboembolism (p=0.24). The risk of venous thromboembolism was significantly higher with increasing lines of chemotherapy (odds ratio 1.14, 95% confidence interval 1.02 to 1.28 per line, p=0.026). There was no significant difference in overall survival (62.9 vs 49.1 median months, p=0.29) between patients with and without venous thromboembolism. CONCLUSIONS: More than 20% of patients with recurrent ovarian cancer developed a venous thromboembolism, and most occurred after three or more lines of treatment. The risk of venous thromboembolism was higher with increasing lines of chemotherapy. While venous thromboembolism did not appear to impact survival in this population, nearly half required hospitalization, emphasizing the morbidity of venous thromboembolism and potential impact on healthcare costs. Further studies are needed to improve risk stratification for venous thromboembolism in this high risk population.
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Neoplasias Ovarianas , Tromboembolia Venosa , Humanos , Feminino , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Estudos Retrospectivos , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/complicações , Pessoa de Meia-Idade , Incidência , Idoso , Recidiva Local de Neoplasia/epidemiologia , Adulto , Estudos de Coortes , Fatores de RiscoRESUMO
INTRODUCTION AND HYPOTHESIS: Combined surgical procedures with sacrocolpopexy (SCP) and rectopexy (RP) are more commonly being performed for treatment of multicompartment pelvic organ prolapse. This study aimed to compare healthcare resource utilization (HRU) within 6 weeks following combined surgery (SCP-RP) versus SCP alone (SCP-only). We hypothesized that concomitant RP does not impact HRU. METHODS: A retrospective cohort study of patients who underwent minimally invasive SCP from 2017 to 2022 was conducted at a tertiary referral center. Patients were grouped based on the performance of concomitant RP. HRU was defined as a composite of unscheduled office visits, emergency department visits, and readmissions before the 6-week postoperative visit. HRU was compared in the SCP-RP and SCP-only groups. Multivariable regression analysis was performed to identify factors associated with HRU. RESULTS: There were 144 patients in the SCP-RP group and 405 patients in the SCP-only group. Patient characteristics were similar between the two groups, with the following exceptions: the SCP-RP group was older, more likely to have comorbid conditions, and live >60 miles from the hospital. Of the 549 patients, 183 (33.3%) had ≥1 HRU encounter within 6 weeks after surgery. However, there was no difference between the SCP-RP and SCP-only groups in composite HRU (34.0% vs 33.1%, p = 0.84). The most common reasons for HRU were pain, urinary tract infection symptoms, and wound issues. Concomitant mid-urethral sling was associated with a two-fold increased risk of HRU after surgery. CONCLUSIONS: One in 3 patients undergoing minimally invasive SCP had at least one unanticipated encounter within 6 weeks after surgery. Concomitant RP was not associated with increased postoperative HRU.
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Procedimentos Cirúrgicos em Ginecologia , Procedimentos Cirúrgicos Minimamente Invasivos , Prolapso de Órgão Pélvico , Humanos , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Prolapso de Órgão Pélvico/cirurgia , Idoso , Procedimentos Cirúrgicos em Ginecologia/estatística & dados numéricos , Procedimentos Cirúrgicos em Ginecologia/métodos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Reto/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Readmissão do Paciente/estatística & dados numéricos , Sacro/cirurgiaRESUMO
OBJECTIVES: Venous thromboembolism (VTE) occurs in 0.4%-0.7% of benign hysterectomies. Pelvic vascular compression secondary to fibroids may elevate VTE risk. We aimed to evaluate the incidence and timing of VTE among individuals undergoing hysterectomy for fibroids and other benign indications. METHODS: Retrospective cohort study of patients who underwent a hysterectomy for fibroid and non-fibroid indications from January 2015 to December 2021. Main outcome measure was VTE consisting of pulmonary embolism or deep venous thrombosis diagnosed during 3 periods: (1) preoperative (1 year before surgery until day before surgery), (2) early postoperative (surgery date through 6 weeks after surgery), and (3) late postoperative (6 weeks to 1 year after surgery). Demographics, comorbidities, surgical characteristics, and VTE rates were compared by indication. RESULTS: A total of 263 844 individuals with fibroids and 203 183 without were identified. In total, 1.1% experienced VTE. On multivariable regression (adjusted demographic confounders and route of surgery), the presence of fibroids was associated with increased odds of preoperative (adjusted odds ratio [aOR] 1.12; 95% CI 1.03-1.22, P = 0.011) and reduced odds of late postoperative VTE (aOR 0.81; 95% CI 0.73-0.91, P < 0.001). For individuals with fibroids, uterine weight ≥250 g and undergoing laparotomy were independently associated with preoperative (aOR 1.29; 95% CI 1.09-1.52, P = 0.003 and aOR 2.32; 95% CI 2.10-2.56, P < 0.001) and early postoperative VTE (aOR 1.32; 95% CI 1.08-1.62, P = 0.006 and aOR 1.72; 95% CI 1.50-1.96, P < 0.001). CONCLUSIONS: Patients with fibroids were at increased odds of having VTE 1 year before hysterectomy. For those with fibroids, elevated uterine weight and laparotomy were associated with greater risk of preoperative and early postoperative VTEs.
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Histerectomia , Leiomioma , Complicações Pós-Operatórias , Neoplasias Uterinas , Tromboembolia Venosa , Humanos , Feminino , Histerectomia/efeitos adversos , Estudos Retrospectivos , Leiomioma/cirurgia , Leiomioma/complicações , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Pessoa de Meia-Idade , Adulto , Neoplasias Uterinas/cirurgia , Neoplasias Uterinas/complicações , Complicações Pós-Operatórias/epidemiologia , Fatores de Risco , Estados Unidos/epidemiologia , Incidência , Estudos de CoortesRESUMO
OBJECTIVES: Decisional conflict and regret about prenatal genetic screening and diagnostic tests may have important consequences in the current pregnancy and for future reproductive decisions. Identifying mechanisms that reduce conflict associated with the decision to use or decline these options is necessary for optimal patient counseling. METHODS: We conducted a cluster-randomized controlled trial of a shared decision-making tool (NEST) at the beginning of prenatal care. Enrolled patients completed follow-up surveys at the time of testing (QTT) and in the second-third trimester (QFF), including the Decision Conflict Scale (DCS). Total DCS scores were analyzed using a multivariate linear mixed-effect model. RESULTS: Of the total number of participants (n=502) enrolled, 449 completed the QTT and QFF surveys. The mean age of participants was 31.6±3.8, with most parous at the time of study participation (n=321; 71.7â¯%). Both the NEST (the intervention) and control groups had lower median total DCS scores at QFF (NEST 13.3 [1.7, 25.0] vs. control 16.7 [1.7, 25.0]; p=0.24) compared to QTT (NEST 20.8 [5.0, 25.0] vs. control 18.3 [3.3, 26.7]; p=0.89). Participants exposed to NEST had lower decisional conflict at QFF compared to control (ß -3.889; [CI -7.341, -0.437]; p=0.027). CONCLUSIONS: Using a shared decision-making tool at the start of prenatal care decreased decisional conflict regarding prenatal genetic testing. Such interventions have the potential to provide an important form of decision-making support for patients facing the unique type of complex and preference-based choices about the use of prenatal genetic tests.
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Conflito Psicológico , Testes Genéticos , Cuidado Pré-Natal , Diagnóstico Pré-Natal , Humanos , Feminino , Gravidez , Adulto , Cuidado Pré-Natal/métodos , Cuidado Pré-Natal/psicologia , Diagnóstico Pré-Natal/psicologia , Diagnóstico Pré-Natal/métodos , Tomada de Decisão Compartilhada , Tomada de DecisõesRESUMO
BACKGROUND: Among six extant tiger subspecies, the South China tiger (Panthera tigris amoyensis) once was widely distributed but is now the rarest one and extinct in the wild. All living South China tigers are descendants of only two male and four female wild-caught tigers and they survive solely in zoos after 60 years of effective conservation efforts. Inbreeding depression and hybridization with other tiger subspecies were believed to have occurred within the small, captive South China tiger population. It is therefore urgently needed to examine the genomic landscape of existing genetic variation among the South China tigers. RESULTS: In this study, we assembled a high-quality chromosome-level genome using long-read sequences and re-sequenced 29 high-depth genomes of the South China tigers. By combining and comparing our data with the other 40 genomes of six tiger subspecies, we identified two significantly differentiated genomic lineages among the South China tigers, which harbored some rare genetic variants introgressed from other tiger subspecies and thus maintained a moderate genetic diversity. We noticed that the South China tiger had higher FROH values for longer runs of homozygosity (ROH > 1 Mb), an indication of recent inbreeding/founder events. We also observed that the South China tiger had the least frequent homozygous genotypes of both high- and moderate-impact deleterious mutations, and lower mutation loads than both Amur and Sumatran tigers. Altogether, our analyses indicated an effective genetic purging of deleterious mutations in homozygous states from the South China tiger, following its population contraction with a controlled increase in inbreeding based on its pedigree records. CONCLUSIONS: The identification of two unique founder/genomic lineages coupled with active genetic purging of deleterious mutations in homozygous states and the genomic resources generated in our study pave the way for a genomics-informed conservation, following the real-time monitoring and rational exchange of reproductive South China tigers among zoos.
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Tigres , Animais , Feminino , Masculino , Tigres/genética , Metagenômica , Genoma , Genômica , China , Conservação dos Recursos NaturaisRESUMO
Ciliated protozoans perform extreme forms of programmed somatic DNA rearrangement during development. The model ciliate Tetrahymena thermophila removes 34% of its germline micronuclear genome from somatic macronuclei by excising thousands of internal eliminated sequences (IESs), a process that shares features with transposon excision. Indeed, piggyBac transposon-derived genes are necessary for genome-wide IES excision in both Tetrahymena (TPB2 [Tetrahymena piggyBac-like 2] and LIA5) and Paramecium tetraurelia (PiggyMac). T. thermophila has at least three other piggyBac-derived genes: TPB1, TPB6, and TPB7 Here, we show that TPB1 and TPB6 excise a small, distinct set of 12 unusual IESs that disrupt exons. TPB1-deficient cells complete mating, but their progeny exhibit slow growth, giant vacuoles, and osmotic shock sensitivity due to retention of an IES in the vacuolar gene DOP1 (Dopey domain-containing protein). Unlike most IESs, TPB1-dependent IESs have piggyBac-like terminal inverted motifs that are necessary for excision. Transposon-like excision mediated by TPB1 and TPB6 provides direct evidence for a transposon origin of not only IES excision machinery but also IESs themselves. Our study highlights a division of labor among ciliate piggyBac-derived genes, which carry out mutually exclusive categories of excision events mediated by either transposon-like features or RNA-directed heterochromatin.
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Elementos de DNA Transponíveis/genética , Rearranjo Gênico/genética , Genes de Protozoários/genética , Genoma de Protozoário/genética , Proteínas de Protozoários/metabolismo , Tetrahymena thermophila/genética , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Inativação de Genes , Estágios do Ciclo de Vida , Proteínas de Protozoários/genética , Tetrahymena thermophila/crescimento & desenvolvimento , Vacúolos/genéticaRESUMO
Programmed cell death 1 ligand 1 (PD-L1) is an important immunosuppressive molecule, which inhibits the function of T cells and other immune cells by binding to the receptor programmed cell death-1. The PD-L1 expression disorder plays an important role in the occurrence, development, and treatment of sepsis or other inflammatory diseases, and has become an important target for the treatment of these diseases. Mesenchymal stem cells (MSCs) are a kind of pluripotent stem cells with multiple differentiation potential. In recent years, MSCs have been found to have a strong immunosuppressive ability and are used to treat various inflammatory insults caused by hyperimmune diseases. Moreover, PD-L1 is deeply involved in the immunosuppressive events of MSCs and plays an important role in the treatment of various diseases. In this review, we will summarize the main regulatory mechanism of PD-L1 expression, and discuss various biological functions of PD-L1 in the immune regulation of MSCs.
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Antígeno B7-H1 , Imunomodulação , Células-Tronco Mesenquimais , Humanos , Antígeno B7-H1/metabolismo , Células-Tronco Mesenquimais/imunologia , Linfócitos T/metabolismoRESUMO
The conventional conductive three-dimensional (3D) host fails to effectively stabilize lithium metal anodes (LMAs) due to the internal incongruity arising from nonuniform lithium-ion gradient and uniform electric fields. This results in undesirable Li "top-growth" behavior and dendritic Li growth, significantly impeding the practical application of LMAs. Herein, we construct a 3D hierarchical host with gradient-distributed dielectric properties (GDD-CH) that effectively regulate Li-ion diffusion and deposition behavior. It comprises a 3D carbon fiber host modified by layer-by-layer bottom-up attenuating Sb particles, which could promote Li-ion homogeneously distribution and reduce ion concentration gradient via unique gradient dielectric polarization. Sb transforms into superionic conductive Li3Sb alloy during cycling, facilitating Li-ion dredging and pumps towards the bottom, dominating a bottom-up deposition regime confirmed by COMSOL Multiphysics simulations and physicochemical characterizations. Consequently, a stable cycling performance of symmetrical cells over 2000â h under a high current density of 10â mA cm-2 is achieved. The GDD-CH-based lithium metal battery shows remarkable cycling stability and ultra-high energy density of 378â Wh kg-1 with a low N/P ratio (1.51). This strategy of dielectric gradient design broadens the perspective for regulating the Li deposition mechanism and paves the way for developing high-energy-density lithium metal anodes with long durability.
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Metal sulfide (MS) is regarded as a promising candidate of the anode materials for sodium-ion battery (SIB) with ideal capacity and low cost, yet still suffers from the inferior cycling stability and voltage degradation. Herein, the coordination relationship between the discharge product Na2S with the Na+ (NaPF6) in the electrolyte, is revealed as the root cause for the cycling failure of MS. Na+-coordination effect assistants the dissolution of Na2S, further delocalizing Na2S from the reaction interface under the function of electric field, which leads to the solo oxidation of the discharge product element metal without the participation of Na2S. Besides, the higher highest occupied molecular orbital of Na2S suggest the facilitated Na2S solo oxidation to produce sodium polysulfides (NaPSs). Based on these, lowering the Na+ concentration of the electrolyte is proposed as a potential improvement strategy to change the coordination environment of Na2S, suppressing the side reactions of the solo-oxidation of element metal and Na2S. Consequently, the enhanced conversion reaction reversibility and prolonged cycle life are achieved. This work renders in-depth perception of failure mechanism and inspiration for realizing advanced conversion-type anode.
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BACKGROUND: Compaction is an important marker of embryonic genome activation and marks a critical step in the development to blastocyst. The objective of our study was to determine whether visualization of the embryonic compaction process through time-lapse imaging (TL) can assist in predicting the kinetics of embryo development as well as the likelihood for blastocyst formation, grade, or ploidy. METHODS: This study is a retrospective review of prospectively collected datafrom a single academic institution. Couples included were thosewho underwent preimplantation genetic testing for aneuploidy (PGT-A) following in vitro fertilization between Januaryand December 2020. Embryos were cultured in the Embrysocope. Embryo morphokinetic data was prospectively collected and analyzed.TL videos werelater reviewed in detail for compaction pattern. Embryo compaction patterns (CP) were categorized as follows: 1) full compaction (CP-F), 2) partial compaction with cell extrusion (P-ext), 3) partial compactionwith cell exclusion (P-exc) and 4) partial compactionwith both cell extrusion and exclusion (P-both). Assessment of embryo decompaction and re-compaction was evaluated. The association between CP, morphokinetic parameters,blastocyst formation, grade and ploidy were then analyzed. RESULTS: A total of 349 embryos were studied. Amongst embryos which progressed to morula (n = 281), the distribution of compaction patterns were: CP-F 45.6%, P-ext12.5%, P-exc29.5% and P-both 12.5%. Embryos exhibiting a CP-F were more likely to proceed to blastocyst compared with those that demonstrated partial compaction patterns (p = 0.006). When compared to CP-F, partial compaction patterns were significantly associated with poorer ICM and TE grades (P < 0.001). Of the 281 morula, 59.8% (n = 168) demonstrated at least one episode of decompaction and re-compaction. Of the 249 blastocysts formed, 200 were cryopreserved for future use after undergoing PGT-A evaluation. Of those, 42.5% were diagnosed as euploid, 39.0% as aneuploid, 9.0% as mosaic and 9.5% had no result. When compared to CP-F, partialCPs exhibited a significantly greater percentage of mosaic embryos (3.6% v. 15.6%, p = 0.032). Additionally, we found that a greater percentage of embryos demonstrating CP-F exhibited morphokinetics that fell into optimal ranges for embryo development when compared to those with partial compaction patterns. CONCLUSION: Time-lapse visualization of compaction patterns identified exclusions and/or extrusions as negative indicators of blastocyst formation and blastocyst grade. When compared to full compaction patterns, partial compaction patterns were associated with delayed embryonic development as well as lower rates of optimal kinetic development.
Assuntos
Diagnóstico Pré-Implantação , Gravidez , Feminino , Humanos , Diagnóstico Pré-Implantação/métodos , Técnicas de Cultura Embrionária/métodos , Desenvolvimento Embrionário/fisiologia , Testes Genéticos/métodos , Aneuploidia , Blastocisto/fisiologia , Fertilização in vitro/métodos , Estudos RetrospectivosRESUMO
Recognition of self and nonself is important for outcrossing organisms, and different mating types establish the barrier against self-mating. In the unicellular ciliate T. thermophila, mating type determination requires complex DNA rearrangements at a single mat locus during conjugation to produce a type-specific gene pair (MTA and MTB) for 1 of 7 possible mating types. Surprisingly, we found that decreased expression of the DNA breakage-repair protein Ku80 at late stages of conjugation generated persistent selfing phenotype in the progeny. DNA analysis revealed multiple mating-type gene pairs as well as a variety of mis-paired, unusually arranged mating-type genes in these selfers that resemble some proposed rearrangement intermediates. They are found also in normal cells during conjugation and are lost after 10 fissions but are retained in Ku mutants. Silencing of TKU80 or TKU70-2 immediately after conjugation also generated selfing phenotype, revealing a hidden DNA rearrangement process beyond conjugation. Mating reactions between the mutant and normal cells suggest a 2-component system for self-nonself-recognition through MTA and MTB genes.