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1.
Opt Lett ; 49(6): 1389-1392, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489407

RESUMO

Optical multiplexing technologies, by utilizing various dimensions of light, can effectively expand the information capacity and density for holography but may also lead to multiplexing cross talk. Here, we propose and demonstrate a novel, to our knowledge, multiplicative-noise-multiplexing holography by utilizing the orthogonality between multiplicative noises as a multiplexing dimension. The results prove that this holography can provide a new multiplexing dimension, significantly enhancing information capacity and effectively lowering cross talk. This promising scheme for ultrahigh-capacity holography has the potential to address the limitations of traditional holographic multiplexing technologies.

3.
Front Endocrinol (Lausanne) ; 14: 1233475, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37916146

RESUMO

Objective: To build a prediction model for live birth delivery per intracytoplasmic sperm injection (ICSI) in iNOA patients by obtaining sperm by microdissection testicular sperm extraction (mTESE). Methods: A retrospective cohort study of 377 couples with iNOA male partners treated with 519 mTESE-ICSI cycles was conducted from September 2013 to July 2021 at the Reproductive Medical Centre of Peking University Third Hospital. Following exclusions, 377 couples with iNOA male partners treated with 482 mTESE-ICSIs were included. A prediction model for live birth delivery per ICSI cycle was built by multivariable logistic regression and selected by 10-fold cross-validation. Discrimination was evaluated by c-statistics and calibration was evaluated by the calibration slope. Results: The live birth delivery rate per mTESE-ICSI cycle was 39.21% (189/482) in these couples. The model identified that the presence of motile sperm during mTESE, bigger testes, higher endometrial thickness on the day of human chorionic gonadotrophin (hCG) administration (ET-hCG), and higher quality embryos are associated with higher live birth delivery success rates. The results of the model were exported based on 10-fold cross-validation. In addition, the area under the mean ROC curve was 0.71 ± 0.05 after 10-fold cross-validation, indicating that the prediction model had certain prediction precision. A calibration plot with an estimated intercept of -1.653 (95% CI: -13.403 to 10.096) and a slope of 1.043 (95% CI: 0.777 to 1.308) indicated that the model was well-calibrated. Conclusion: Our prediction model will provide valuable information about the chances of live birth delivery in couples with iNOA male partners who have a plan for mTESE-ICSI treatment. Therefore, it can improve and personalize counseling for the medical treatment of these patients.


Assuntos
Azoospermia , Gravidez , Feminino , Humanos , Masculino , Azoospermia/terapia , Nascido Vivo/epidemiologia , Estudos Retrospectivos , Modelos Estatísticos , Prognóstico , Sêmen
4.
iScience ; 26(11): 108030, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37920670

RESUMO

Genetic studies have elucidated the critical roles of Phf7 in germline development in animals; however, the exact etiology of Phf7 mutations leading to male infertility and the possibility of mechanism-based therapy are still unclear and warrant further investigation. Using the Phf7 knockout mouse model, we verified that genetic defects were responsible for male infertility by preventing histone-to-protamine exchange, as previously reported. The deficiency of spermatogenesis caused by Phf7 deletion through the endogenous retrovirus-mediated activation of the immune pathway is a common mechanism of infertility. Furthermore, we identified PPARα as a promising target of immunity and inflammation in the testis, where endogenous retroviruses are suppressed, and Phf7 as a crucial regulator of endogenous retrovirus-mediated immune regulation and revealed its role as an epigenetic reader. The loss of Phf7 activates immune pathways, which can be rescued by the PPARα agonist astaxanthin. These results showed that astaxanthin is a potential therapeutic agent for treating male infertility. The findings in our study provide insights into the molecular mechanisms underlying male infertility and suggest potential targets for future research and therapeutic development.

5.
Front Microbiol ; 14: 1247348, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37886063

RESUMO

Introduction: Milk fat is the most variable nutrient in milk, and recent studies have shown that rumen bacteria are closely related to milk fat. However, there is limited research on the relationship between rumen bacteria and milk fatty. Fatty acids (FAs) are an important component of milk fat and are associated with various potential benefits and risks to human health. Methods: In this experiment, forty-five healthy Holstein dairy cows with alike physiological and productive conditions were selected from medium-sized dairy farms and raised under the same feeding and management conditions. The experimental period was two weeks. During the experiment, raw milk and rumen fluid were collected, and milk components were determined. In this study, 8 high milk fat percentage (HF) dairy cows and 8 low milk fat percentage (LF) dairy cows were selected for analysis. Results: Results showed that the milk fat percentage in HF group was significantly greater than that of the dairy cows in the LF group. 16S rRNA gene sequencing showed that the rumen bacterial abundance of HF dairy cows was significantly higher than that in LF dairy cows; at the genus level, the bacterial abundances of Prevotellaceae_UCG-001, Candidatus_Saccharimonas, Prevotellaceae_UCG-003, Ruminococcus_1, Lachnospiraceae_XPB1014_group, Lachnospiraceae_AC2044_group, probable_genus_10 and U29-B03 in HF group were significantly higher than those in the LF group. Spearman rank correlation analysis indicated that milk fat percentage was positively related to Prevotellaceae_UCG-001, Candidatus_Saccharimonas, Prevotellaceae_UCG-003, Ruminococcus_1, Lachnospiraceae_XPB1014_group, Lachnospiraceae_AC2044_group, probable_genus_10 and U29-B03. Furthermore, Prevotellaceae_UCG-001 was positively related to C14:0 iso, C15:0 iso, C18:0, Ruminococcus_1 with C18:1 t9, Lachnospiraceae_AC2044_group with C18:1 t9 and C18:1 t11, U29-B03 with C15:0 iso. Discussion: To sum up, rumen bacteria in dairy cows are related to the variation of milk fat, and some rumen bacteria have potential effects on the deposition of certain fatty acids in raw milk.

6.
Sensors (Basel) ; 23(18)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37765904

RESUMO

The precursors that appear when geological disasters occur are geotechnical deformations. This paper studies the TDR (Time Domain Reflection) measurement technology for the distributed measurement of geotechnical deformation using parallel spiral wire as a sensor, which is used for monitoring and early warning detection of geological disasters. Based on the mechanism of the electromagnetic field distribution parameters of the parallel spiral sensing wire, the relationship between the stretching amount of the parallel spiral wire and the change in its characteristic impedance is analyzed. When the parallel spiral wire is buried in the soil, the geotechnical deformation causes the parallel spiral wire to be stretched, and according to its characteristic impedance change, the stretching position and the stretching degree can be obtained, thus realizing the distributed measurement of geotechnical deformation. Based on this principle, the TDR measurement system is developed, and a local single-point stretching amount and stretching positioning experiment are designed for the parallel spiral sensing line to verify the effectiveness of the sensing technology and the usability of the measurement system.

7.
Small ; 19(48): e2303924, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37537706

RESUMO

Commercial polymer separators usually have limited porosity, poor electrolyte wettability, and poor thermal and mechanical stability, which can deteriorate the performance of battery, especially at high current densities. In this work, a functional polyethylene (PE) separator is prepared by surface engineering a layer of Ti-doped SiO2 @Al2 O3 particles (denoted as ST@Al2 O3 -PE) with strong Lewis acid property and uniform porous structure on one side of the PE separator. On the other hand, ST@Al2 O3 particles with abundant pore structures and large cavities can store a large amount of electrolyte, providing a shortened pathway for lithium-ion transport, and the Lewis acid sites and porous structure of the ST@Al2 O3 can tune Li plating/stripping behavior and stabilize the lithium metal anode. The ST@Al2 O3 -PE separators exhibit better ionic conductivity (5.55 mS cm-1 ) and larger lithium-ion transference number (0.62). At a current density of 1 mA cm-2 , Li/Li symmetric cells with ST@Al2 O3 -PE separator can be stably cycled for more than 400 h, and both lithium iron phosphate /Li cells and lithium cobaltate/Li cells with ST@Al2 O3 -PE separator have good cycling and rate performance. This work provides a new strategy for developing functional separators and promoting the application of lithium metal batteries.

8.
Front Pediatr ; 11: 1199489, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37484777

RESUMO

Background: Mucolipidosis type II (MLII), or I-cell disease, is a rare lysosomal storage disease (LSD) caused by variants in the GNPTAB gene. MLII patients exhibit clinical phenotypes in the prenatal or neonatal stage, such as marked dysmorphic features, cardiac involvement, respiratory symptoms, dysostosis multiplex, severe growth abnormalities, and mental and motor developmental abnormalities. The median age at diagnosis for MLII is 0.7 years, the median survival is 5.0 years, and the median age at death is 1.8 years. No cure for MLII exists. Methods: Sanger sequencing of the GNPTAB gene identified the compound heterozygous mutations c.673C > T in exon 7 and c.1090C > T in exon 9, which were novel double heterozygous mutations first reported in China. For the first time, we describe our experience in the use of HSCT for MLII. Our patient underwent HSCT with cells from a 9/10 human leukocyte antigen (HLA)-matched unrelated donor at 12 months of age. Myeloid neutrophil and platelet engraftment occurred on Days 10 and 11, respectively. Results: The patient's limb muscle tension was significantly reduced, and his gross and fine motor skills were improved four months after transplantation. DST(Developmental Screen Test) results showed that the patient's fine motor skills and mental development were improved compared with before HSCT. Conclusion: MLII is a very severe lysosomal storage disease, to date, only 3 cases have been reported on the use of HSCT to treat MLII. Our data show that HSCT is a potential way to prolong the life of patients and improve their quality of life. Due to the lack of comparable data and time, the exact benefit remains unclear in MLII patients. Longer-term follow-up and in-depth prospective studies are indispensable.

9.
Bioinformatics ; 39(7)2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37354494

RESUMO

MOTIVATION: Gene expression is characterized by stochastic bursts of transcription that occur at brief and random periods of promoter activity. The kinetics of gene expression burstiness differs across the genome and is dependent on the promoter sequence, among other factors. Single-cell RNA sequencing (scRNA-seq) has made it possible to quantify the cell-to-cell variability in transcription at a global genome-wide level. However, scRNA-seq data are prone to technical variability, including low and variable capture efficiency of transcripts from individual cells. RESULTS: Here, we propose a novel mathematical theory for the observed variability in scRNA-seq data. Our method captures burst kinetics and variability in both the cell size and capture efficiency, which allows us to propose several likelihood-based and simulation-based methods for the inference of burst kinetics from scRNA-seq data. Using both synthetic and real data, we show that the simulation-based methods provide an accurate, robust and flexible tool for inferring burst kinetics from scRNA-seq data. In particular, in a supervised manner, a simulation-based inference method based on neural networks proves to be accurate and useful when applied to both allele and nonallele-specific scRNA-seq data. AVAILABILITY AND IMPLEMENTATION: The code for Neural Network and Approximate Bayesian Computation inference is available at https://github.com/WT215/nnRNA and https://github.com/WT215/Julia_ABC, respectively.


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Perfilação da Expressão Gênica/métodos , Análise de Sequência de RNA/métodos , Software , Teorema de Bayes , Cinética , Funções Verossimilhança , Análise de Célula Única/métodos , RNA
10.
Front Microbiol ; 14: 1156795, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37138618

RESUMO

Introduction: Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) is a powerful analytical technique that has been applied to a wide variety of applications ranging from proteomics to clinical diagnostics. One such application is its use as a tool for discovery assays, such as monitoring the inhibition of purified proteins. With the global threat from antimicrobial-resistant (AMR) bacteria, new and innovative solutions are required to identify new molecules that could revert bacterial resistance and/or target virulence factors. Here, we used a whole cell-based MALDI-TOF lipidomic assay using a routine MALDI Biotyper Sirius system operating in linear negative ion mode combined with the MBT Lipid Xtract kit to discover molecules targeting bacteria that are resistant to polymyxins, which are considered last-resort antibiotics. Methods: A library of 1200 natural compounds was tested against an E. coli strain expressing mcr-1, which is known to modify lipid A by adding phosphoethanolamine (pETN), making the strain resistant to colistin. Results and Discussion: Using this approach, we identified 8 compounds that led to a decrease in this lipid A modification by MCR-1 and could potentially be employed to revert resistance. Taken together, as-proof-of-principle, the data we report here represent a new workflow based on the analysis of bacterial lipid A by routine MALDI-TOF for the discovery of inhibitors that could target bacterial viability and/or virulence.

11.
Cell Rep ; 42(5): 112472, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37149862

RESUMO

Glioblastoma (GBM) recurrence originates from invasive margin cells that escape surgical debulking, but to what extent these cells resemble their bulk counterparts remains unclear. Here, we generated three immunocompetent somatic GBM mouse models, driven by subtype-associated mutations, to compare matched bulk and margin cells. We find that, regardless of mutations, tumors converge on common sets of neural-like cellular states. However, bulk and margin have distinct biology. Injury-like programs associated with immune infiltration dominate in the bulk, leading to the generation of lowly proliferative injured neural progenitor-like cells (iNPCs). iNPCs account for a significant proportion of dormant GBM cells and are induced by interferon signaling within T cell niches. In contrast, developmental-like trajectories are favored within the immune-cold margin microenvironment resulting in differentiation toward invasive astrocyte-like cells. These findings suggest that the regional tumor microenvironment dominantly controls GBM cell fate and biological vulnerabilities identified in the bulk may not extend to the margin residuum.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Células-Tronco Neurais , Animais , Camundongos , Glioblastoma/genética , Glioblastoma/patologia , Diferenciação Celular , Microambiente Tumoral , Células-Tronco Neurais/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia
12.
Adv Sci (Weinh) ; 10(17): e2206852, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37083227

RESUMO

Nonobstructive azoospermia (NOA) is one of the most important causes of male infertility, accounting for 10-15% of infertile men worldwide. Among these, more than 70% of cases are idiopathic NOA (iNOA), whose pathogenesis and molecular basis remain unknown. This work profiles 3696 human testicular single-cell transcriptomes from 17 iNOA patients, which are classified into four classes with different arrest periods and variable cell proportions based on the gene expression patterns and pathological features. Genes related to the cell cycle, energy production, and gamete generation show obvious abnormalities in iNOA germ cells. This work identifies several candidate causal genes for iNOA, including CD164, LELP1, and TEX38, which are significantly downregulated in iNOA germ cells. Notably, CD164 knockdown promotes apoptosis in spermatogonia. Cellular communications between spermatogonial stem cells and Sertoli cells are disturbed in iNOA patients. Moreover, BOD1L2, C1orf194, and KRTCAP2 are found to indicate testicular spermatogenic capacity in a variety of testicular diseases, such as Y-chromosome microdeletions and Klinefelter syndrome. In general, this study analyzes the pathogenesis of iNOA from the perspective of germ cell development, transcription factor (TF) regulatory networks, as well as germ cell and somatic cell interactions, which provides new ideas for clinical diagnosis.


Assuntos
Azoospermia , Infertilidade Masculina , Humanos , Masculino , Azoospermia/genética , Azoospermia/metabolismo , Azoospermia/patologia , Infertilidade Masculina/patologia , Testículo/metabolismo , Testículo/patologia , Células Germinativas
13.
Small Methods ; 7(6): e2300186, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37093188

RESUMO

Lithium-sulfur batteries (LSBs) have become very promising next-generation energy-storage technologies owing to their high energy densities and cost-effectiveness. However, the poor electrical conductivity of the active material, volume changes that occur during cycling, the "shuttle effect" involving lithium polysulfides (LiPSs), and lithium dendrite growth limit their commercializability. Herein, the preparation of a CC@VS2 -VO2 @Li2 S@C electrode prepared by the in situ growth of a VS2 -VO2 heterostructure on carbon cloth (CC), loaded with Li2 S, and finally coated with a carbon shell, is reported. The cell with the CC@VS2 -VO2 @Li2 S@C cathode exhibits superior cycling stability and rate performance owing to synergy between its various components. The cell delivers a high discharge specific capacity of 919.8 mA g-1 at 0.2 C, with a capacity of 588.9 mAh g-1 retained after 500 cycles with an average capacity attenuation of 0.072% per cycle. The cell exhibits discharge capacities of 937.6, 780.2, 641.9, 541, and 462.8 mAh g-1 at current densities of 0.2, 0.5, 1, 2, and 3 C, respectively. This study provides a new approach for catalyzing LiPS conversion and promoting LSB applications.

14.
R Soc Open Sci ; 10(3): 221444, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36968241

RESUMO

Mathematical oncology provides unique and invaluable insights into tumour growth on both the microscopic and macroscopic levels. This review presents state-of-the-art modelling techniques and focuses on their role in understanding glioblastoma, a malignant form of brain cancer. For each approach, we summarize the scope, drawbacks and assets. We highlight the potential clinical applications of each modelling technique and discuss the connections between the mathematical models and the molecular and imaging data used to inform them. By doing so, we aim to prime cancer researchers with current and emerging computational tools for understanding tumour progression. By providing an in-depth picture of the different modelling techniques, we also aim to assist researchers who seek to build and develop their own models and the associated inference frameworks. Our article thus strikes a unique balance. On the one hand, we provide a comprehensive overview of the available modelling techniques and their applications, including key mathematical expressions. On the other hand, the content is accessible to mathematicians and biomedical scientists alike to accommodate the interdisciplinary nature of cancer research.

15.
Transl Androl Urol ; 12(2): 187-196, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36915889

RESUMO

Background: Male reproductive health has become a serious public health concern, and semen quality is essential to male reproduction. We aimed to investigate geographical differences in the semen quality of sperm donors from northern and southern China by enrolling donors across the country. Methods: A total of 1,012 sperm donors were enrolled in this study between 2015 and 2019. Donors were first divided into two parts based on their birthplace according to the "Qinling-Huaihe" line, and secondly, by their residential latitude. Finally, donors were re-classified into two groups (typically north and south) which contained 667 samples. Results: Statistically significant differences in sperm concentration were observed among men from different latitudes in China (P=0.04). The sperm concentrations of males from 18° to 27° north latitude were significantly lower than those from 36° to 45° and 45° to 54° [median 131, 134, and 146, respectively, P=0.021 (18° to 27° vs. 36° to 45°) and P=0.01 (18° to 27° vs. 45° to 54°)]. Conclusion: We hypothesize environmental pollution and mental stress due to the increased population size may be the main factors underlying differences in the sperm quality of men in northern and southern China.

16.
Curr Biol ; 33(6): 1082-1098.e8, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36841240

RESUMO

Despite their latent neurogenic potential, most normal parenchymal astrocytes fail to dedifferentiate to neural stem cells in response to injury. In contrast, aberrant lineage plasticity is a hallmark of gliomas, and this suggests that tumor suppressors may constrain astrocyte dedifferentiation. Here, we show that p53, one of the most commonly inactivated tumor suppressors in glioma, is a gatekeeper of astrocyte fate. In the context of stab-wound injury, p53 loss destabilized the identity of astrocytes, priming them to dedifferentiate in later life. This resulted from persistent and age-exacerbated neuroinflammation at the injury site and EGFR activation in periwound astrocytes. Mechanistically, dedifferentiation was driven by the synergistic upregulation of mTOR signaling downstream of p53 loss and EGFR, which reinstates stemness programs via increased translation of neurodevelopmental transcription factors. Thus, our findings suggest that first-hit mutations remove the barriers to injury-induced dedifferentiation by sensitizing somatic cells to inflammatory signals, with implications for tumorigenesis.


Assuntos
Astrócitos , Células-Tronco Neurais , Astrócitos/patologia , Proteína Supressora de Tumor p53/genética , Receptores ErbB/genética , Mutação
17.
Basic Clin Androl ; 33(1): 8, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36792987

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) outbreak has had a widespread and profound impact on people's mental health. The factors associated with mental symptoms among men diagnosed with infertility, a disease closely related to psychological conditions, remain unclear. The aim of this study is to investigate the risk factors associated with mental symptoms among infertile Chinese men during the pandemic. RESULTS: A total of 4,098 eligible participants were recruited in this cross-sectional, nationwide study, including 2,034 (49.6%) with primary infertility and 2,064 (50.4%) with secondary infertility. The prevalence of mental health conditions was 36.3%, 39.6%, and 6.7% for anxiety, depression, and post-pandemic stress, respectively. Sexual dysfunction is associated with a higher risk with adjusted odds ratios (ORs) of 1.40 for anxiety, 1.38 for depression, and 2.32 for stress. Men receiving infertility drug therapy displayed a higher risk for anxiety (adjusted OR, 1.31) and depression (adjusted OR, 1.28) symptoms, while those receiving intrauterine insemination had a lower risk of anxiety (adjusted OR, 0.56) and depression (adjusted OR, 0.55) symptoms. CONCLUSION: The COVID-19 pandemic has had a significant psychological impact on infertile men. Several psychologically vulnerable populations were identified, including individuals with sexual dysfunction, respondents receiving infertility drug therapy, and those experiencing control measures for COVID-19. The findings provide a comprehensive profile of the mental health status of infertile Chinese men during the COVID-19 outbreak and provide potential psychological intervention strategies.


RéSUMé: CONTEXTE: L'épidémie de maladie à coronavirus 2019 (COVID-19) a eu un impact étendu et profond sur la santé mentale des gens. Les facteurs associés aux symptômes mentaux chez les hommes diagnostiqués comme infertiles, une maladie étroitement liée aux conditions psychologiques, restent flous. L'objectif de cette étude est d'étudier les facteurs de risque associés aux symptômes mentaux chez les hommes chinois infertiles pendant la pandémie. RéSULTATS: Au total, 4 098 participants admissibles ont été recrutés dans cette étude transversale à l'échelle nationale, dont 2 034 (49,6%) présentaient une infertilité primaire et 2 064 (50,4%) une infertilité secondaire. La prévalence des problèmes de santé mentale était respectivement de 36,3 %, 39,6 % et 6,7 % pour l'anxiété, la dépression, et le stress postpandémique. La dysfonction sexuelle est associée à un risque plus élevé avec des odds ratios ajustés (OR) de 1,40 pour l'anxiété, 1,38 pour la dépression et 2,32 pour le stress. Les hommes recevant un traitement médicamenteux contre l'infertilité présentaient un risque plus élevé de symptômes d'anxiété (OR ajusté, 1,31) et de dépression (OR ajusté, 1,28), alors que ceux dont le traitement consistait à faire des inséminations intra-utérines présentaient un risque plus faible de symptômes d'anxiété (OR ajusté, 0,56) et de dépression (OR ajusté, 0,55). CONCLUSIONS: La pandémie de COVID-19 a eu un impact psychologique important sur les hommes infertiles. Plusieurs populations psychologiquement vulnérables ont été identifiées, notamment les personnes souffrant de dysfonction sexuelle, les hommes recevant un traitement médicamenteux contre l'infertilité, et ceux subissant des mesures de contrôle de la COVID-19. Les résultats fournissent un profil complet de l'état de santé mentale des hommes Chinois infertiles pendant l'épidémie de COVID-19 et fournissent des stratégies potentielles d'intervention psychologique.

18.
Asian J Androl ; 25(1): 5-12, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35259786

RESUMO

Spermatogenesis is regulated by several Y chromosome-specific genes located in a specific region of the long arm of the Y chromosome, the azoospermia factor region (AZF). AZF microdeletions are the main structural chromosomal abnormalities that cause male infertility. Assisted reproductive technology (ART) has been used to overcome natural fertilization barriers, allowing infertile couples to have children. However, these techniques increase the risk of vertical transmission of genetic defects. Despite widespread awareness of AZF microdeletions, the occurrence of de novo deletions and overexpression, as well as the expansion of AZF microdeletion vertical transmission, remains unknown. This review summarizes the mechanism of AZF microdeletion and the function of the candidate genes in the AZF region and their corresponding clinical phenotypes. Moreover, vertical transmission cases of AZF microdeletions, the impact of vertical inheritance on male fertility, and the prospective direction of research in this field are also outlined.


Assuntos
Azoospermia , Infertilidade Masculina , Oligospermia , Síndrome de Células de Sertoli , Humanos , Masculino , Azoospermia/genética , Aberrações dos Cromossomos Sexuais , Estudos Prospectivos , Deleção Cromossômica , Cromossomos Humanos Y/genética , Infertilidade Masculina/genética , Síndrome de Células de Sertoli/genética , Oligospermia/genética
19.
Small ; 19(3): e2205532, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36399646

RESUMO

A major issue with Li-O2 batteries is their slow oxygen reduction and evolution kinetics, necessitating catalysts with high catalytic activity to improve reaction kinetics and cycle stability. Herein, a nano-heterostructured catalyst composed of Co3 O4 and Fe2 O3 (Co3 O4 /Fe2 O3 ) with a porous rod morphology is achieved through an interfacial engineering strategy by constructing Fe2 O3 on the Co3 O4 surface, which can function as a high-performance cathode in order to efficiently encourage the oxygen reduction and evolution while also reduce the battery polarization during charging and discharging. The density functional theory (DFT) calculations show the differences in charge density at the interface of nano-heterostructures, demonstrating the occurrence of an electron transfer process in the interface region of Co3 O4 and Fe2 O3 , implying a strong electronic coupling transfer, and in turn changing the electronic structure of the Co3 O4 . This significantly reduces the adsorption energy of LiO2 intermediates, thereby effectively lowering the overpotential. The resultant Li-O2 battery has larger discharge specific capacity, lower overpotential for the efficient oxygen evolution/reduction, as well as good cycling stability of 280 cycles. This work demonstrates an effective method to fabricate the nano-heterostrucutred materials with enhanced catalytic efficiency for advanced energy applications.

20.
Cancer Cell ; 41(1): 70-87.e14, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36332625

RESUMO

The evolution of established cancers is driven by selection of cells with enhanced fitness. Subclonal mutations in numerous epigenetic regulator genes are common across cancer types, yet their functional impact has been unclear. Here, we show that disruption of the epigenetic regulatory network increases the tolerance of cancer cells to unfavorable environments experienced within growing tumors by promoting the emergence of stress-resistant subpopulations. Disruption of epigenetic control does not promote selection of genetically defined subclones or favor a phenotypic switch in response to environmental changes. Instead, it prevents cells from mounting an efficient stress response via modulation of global transcriptional activity. This "transcriptional numbness" lowers the probability of cell death at early stages, increasing the chance of long-term adaptation at the population level. Our findings provide a mechanistic explanation for the widespread selection of subclonal epigenetic-related mutations in cancer and uncover phenotypic inertia as a cellular trait that drives subclone expansion.


Assuntos
Neoplasias , Humanos , Mutação , Neoplasias/genética , Neoplasias/patologia , Fenótipo
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