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1.
Nature ; 603(7900): 284-289, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35236981

RESUMO

Homo sapiens was present in northern Asia by around 40,000 years ago, having replaced archaic populations across Eurasia after episodes of earlier population expansions and interbreeding1-4. Cultural adaptations of the last Neanderthals, the Denisovans and the incoming populations of H. sapiens into Asia remain unknown1,5-7. Here we describe Xiamabei, a well-preserved, approximately 40,000-year-old archaeological site in northern China, which includes the earliest known ochre-processing feature in east Asia, a distinctive miniaturized lithic assemblage with bladelet-like tools bearing traces of hafting, and a bone tool. The cultural assembly of traits at Xiamabei is unique for Eastern Asia and does not correspond with those found at other archaeological site assemblages inhabited by archaic populations or those generally associated with the expansion of H. sapiens, such as the Initial Upper Palaeolithic8-10. The record of northern Asia supports a process of technological innovations and cultural diversification emerging in a period of hominin hybridization and admixture2,3,6,11.


Assuntos
Arqueologia , Hominidae , Comportamento de Utilização de Ferramentas , Animais , Osso e Ossos , China , História Antiga , Humanos , Homem de Neandertal
2.
N Engl J Med ; 388(14): 1272-1283, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36762852

RESUMO

BACKGROUND: The role of endovascular therapy for acute stroke with a large infarction has not been extensively studied in differing populations. METHODS: We conducted a multicenter, prospective, open-label, randomized trial in China involving patients with acute large-vessel occlusion in the anterior circulation and an Alberta Stroke Program Early Computed Tomography Score of 3 to 5 (range, 0 to 10, with lower values indicating larger infarction) or an infarct-core volume of 70 to 100 ml. Patients were randomly assigned in a 1:1 ratio within 24 hours from the time they were last known to be well to undergo endovascular therapy and receive medical management or to receive medical management alone. The primary outcome was the score on the modified Rankin scale at 90 days (scores range from 0 to 6, with higher scores indicating greater disability), and the primary objective was to determine whether a shift in the distribution of the scores on the modified Rankin scale at 90 days had occurred between the two groups. Secondary outcomes included scores of 0 to 2 and 0 to 3 on the modified Rankin scale. The primary safety outcome was symptomatic intracranial hemorrhage within 48 hours after randomization. RESULTS: A total of 456 patients were enrolled; 231 were assigned to the endovascular-therapy group and 225 to the medical-management group. Approximately 28% of the patients in both groups received intravenous thrombolysis. The trial was stopped early owing to the efficacy of endovascular therapy after the second interim analysis. At 90 days, a shift in the distribution of scores on the modified Rankin scale toward better outcomes was observed in favor of endovascular therapy over medical management alone (generalized odds ratio, 1.37; 95% confidence interval, 1.11 to 1.69; P = 0.004). Symptomatic intracranial hemorrhage occurred in 14 of 230 patients (6.1%) in the endovascular-therapy group and in 6 of 225 patients (2.7%) in the medical-management group; any intracranial hemorrhage occurred in 113 (49.1%) and 39 (17.3%), respectively. Results for the secondary outcomes generally supported those of the primary analysis. CONCLUSIONS: In a trial conducted in China, patients with large cerebral infarctions had better outcomes with endovascular therapy administered within 24 hours than with medical management alone but had more intracranial hemorrhages. (Funded by Covidien Healthcare International Trading [Shanghai] and others; ANGEL-ASPECT ClinicalTrials.gov number, NCT04551664.).


Assuntos
Isquemia Encefálica , Infarto Cerebral , Procedimentos Endovasculares , AVC Isquêmico , Trombectomia , Humanos , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/cirurgia , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/cirurgia , China , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , Hemorragias Intracranianas/induzido quimicamente , Hemorragias Intracranianas/etiologia , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/cirurgia , Estudos Prospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Trombectomia/métodos , Resultado do Tratamento
3.
Nucleic Acids Res ; 52(12): 7367-7383, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38808673

RESUMO

Temperature is an important control factor for biologics biomanufacturing in precision fermentation. Here, we explored a highly responsive low temperature-inducible genetic system (LowTempGAL) in the model yeast Saccharomyces cerevisiae. Two temperature biosensors, a heat-inducible degron and a heat-inducible protein aggregation domain, were used to regulate the GAL activator Gal4p, rendering the leaky LowTempGAL systems. Boolean-type induction was achieved by implementing a second-layer control through low-temperature-mediated repression on GAL repressor gene GAL80, but suffered delayed response to low-temperature triggers and a weak response at 30°C. Application potentials were validated for protein and small molecule production. Proteomics analysis suggested that residual Gal80p and Gal4p insufficiency caused suboptimal induction. 'Turbo' mechanisms were engineered through incorporating a basal Gal4p expression and a galactose-independent Gal80p-supressing Gal3p mutant (Gal3Cp). Varying Gal3Cp configurations, we deployed the LowTempGAL systems capable for a rapid stringent high-level induction upon the shift from a high temperature (37-33°C) to a low temperature (≤30°C). Overall, we present a synthetic biology procedure that leverages 'leaky' biosensors to deploy highly responsive Boolean-type genetic circuits. The key lies in optimisation of the intricate layout of the multi-factor system. The LowTempGAL systems may be applicable in non-conventional yeast platforms for precision biomanufacturing.


Assuntos
Regulação Fúngica da Expressão Gênica , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Fatores de Transcrição , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Temperatura Baixa , Galactose/metabolismo , Técnicas Biossensoriais
4.
Proc Natl Acad Sci U S A ; 120(6): e2215305120, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36730199

RESUMO

Photosynthesis of hydrogen peroxide (H2O2) by selective oxygen reduction is a green and cost-effective alternative to the energy-intensive anthraquinone process. Although inexpensive polymeric graphitic carbon nitride (g-C3N4) exhibits the ability to produce H2O2, its disordered and amorphous structure leads to a high recombination rate of photogenerated carriers and hinders charge transfer between layers. Herein, we predict that stacked polymeric g-C3N4 with ion intercalation (K+ and I-) can improve carrier separation and transfer by multiscale computational simulations. The electronic structures of g-C3N4 were tailored and modified by intercalating K+ and I- into the layer-by-layer structures. Guided by the computational predictions, we achieved efficient solar-driven H2O2 production by employing this facile and ion-intercalated crystalline g-C3N4. An H2O2 production rate of 13.1 mM g-1 h-1 and an apparent quantum yield of 23.6% at 400 nm were obtained. The synergistic effects of crystallinity regulation and dual interstitial doping engineering triggered the formation of new light absorption centers, the establishment of rapid charge diffusion channels, and the enhancement of two-electron oxygen reduction characteristics. This work sheds light on the dual tuning of crystallinity and electronic structure and broadens the design principles of organic-conjugated polymer photocatalysts for environmental remediation and energy conservation.

5.
Neuroendocrinology ; 114(4): 356-364, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38160674

RESUMO

INTRODUCTION: Cognitive dysfunction due to reduced neuronal transmission in the brain is a major emerging complication in diabetes. However, recent neuroimaging studies have demonstrated non-linear changes including hyperactivity in the hippocampus during the early stage of diabetes. This study aimed to determine the changes in neuronal activity at a single-cell level in hippocampal CA1 pyramidal neurons in the early stage of streptozotocin-induced type 1 diabetes in mice. METHODS: Whole-cell patch-clamp recordings from acute brain slices were performed in mice over 4 consecutive weeks following the induction of hyperglycaemia using streptozotocin. In addition, microdialysate was collected from CA1 area while the mice were in an arousal state. The concentrations of glutamate and GABA in the microdialysate were then measured using ultra-performance liquid chromatography with mass spectrometry. RESULTS: CA1 neurons in streptozotocin-induced diabetic mice exhibited higher membrane potentials (p = 0.0052), higher frequency of action potentials (p = 0.0052), and higher frequency of spontaneous excitatory post-synaptic currents (p = 0.037) compared with controls during the second week after hyperglycaemia was established. No changes in electrophysiological parameters were observed during the first, the third, and the fourth week. Moreover, the diabetic mice had higher extracellular glutamate concentration in CA1 area compared with controls (p = 0.021) during the second week after the initiation of diabetes. No change in the extracellular GABA concentration was observed. CONCLUSION: Our study demonstrated a temporary state of neuronal hyperactivity at the single-cell level in the hippocampal CA1 region during the early stage of diabetes. This neuronal hyperactivity might be related to altered glutamate metabolism and provide clues for future brain-target intervention.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Hiperglicemia , Camundongos , Animais , Estreptozocina/toxicidade , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Experimental/metabolismo , Hipocampo/metabolismo , Neurônios , Transmissão Sináptica/fisiologia , Ácido Glutâmico/metabolismo , Ácido gama-Aminobutírico/metabolismo , Hiperglicemia/metabolismo
6.
Circ Res ; 130(1): 48-66, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34763521

RESUMO

BACKGROUND: Patients with acute myocardial infarction suffer systemic metabolic dysfunction via incompletely understood mechanisms. Adipocytes play critical role in metabolic homeostasis. The impact of acute myocardial infarction upon adipocyte function is unclear. Small extracellular vesicles (sEVs) critically contribute to organ-organ communication. Whether and how small extracellular vesicle mediate post-MI cardiomyocyte/adipocyte communication remain unknown. METHODS: Plasma sEVs were isolated from sham control (Pla-sEVSham) or 3 hours after myocardial ischemia/reperfusion (Pla-sEVMI/R) and incubated with adipocytes for 24 hours. Compared with Pla-sEVSham, Pla-sEVMI/R significantly altered expression of genes known to be important in adipocyte function, including a well-known metabolic regulatory/cardioprotective adipokine, APN (adiponectin). Pla-sEVMI/R activated 2 (PERK-CHOP and ATF6 [transcription factor 6]-EDEM [ER degradation enhancing alpha-mannosidase like protein 1] pathways) of the 3 endoplasmic reticulum (ER) stress pathways in adipocytes. These pathological alterations were also observed in adipocytes treated with sEVs isolated from adult cardiomyocytes subjected to in vivo myocardial ischemia/reperfusion (MI/R) (Myo-sEVMI/R). Bioinformatic/RT-qPCR analysis demonstrates that the members of miR-23-27-24 cluster are significantly increased in Pla-sEVMI/R, Myo-sEVMI/R, and adipose tissue of MI/R animals. Administration of cardiomyocyte-specific miR-23-27-24 sponges abolished adipocyte miR-23-27-24 elevation in MI/R animals, supporting the cardiomyocyte origin of adipocyte miR-23-27-24 cluster. In similar fashion to Myo-sEVMI/R, a miR-27a mimic activated PERK-CHOP and ATF6-EDEM-mediated ER stress. Conversely, a miR-27a inhibitor significantly attenuated Myo-sEVMI/R-induced ER stress and restored APN production. RESULTS: An unbiased approach identified EDEM3 (ER degradation enhancing alpha-mannosidase like protein 3) as a novel downstream target of miR-27a. Adipocyte EDEM3 deficiency phenocopied multiple pathological alterations caused by Myo-sEVMI/R, whereas EDEM3 overexpression attenuated Myo-sEVMI/R-resulted ER stress. Finally, administration of GW4869 or cardiomyocyte-specific miR-23-27-24 cluster sponges attenuated adipocyte ER stress, improved adipocyte endocrine function, and restored plasma APN levels in MI/R animals. CONCLUSIONS: We demonstrate for the first time that MI/R causes significant adipocyte ER stress and endocrine dysfunction by releasing miR-23-27-24 cluster-enriched small extracellular vesicle. Targeting small extracellular vesicle-mediated cardiomyocyte-adipocyte pathological communication may be of therapeutic potential to prevent metabolic dysfunction after MI/R.


Assuntos
Adipócitos/metabolismo , Comunicação Celular , Estresse do Retículo Endoplasmático , Vesículas Extracelulares/metabolismo , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Fator 6 Ativador da Transcrição/metabolismo , Adiponectina/metabolismo , Animais , Masculino , Proteínas de Membrana/metabolismo , Camundongos , MicroRNAs/metabolismo , Fator de Transcrição CHOP/metabolismo , eIF-2 Quinase/metabolismo
7.
PLoS Comput Biol ; 19(12): e1011677, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38055721

RESUMO

RNA modification is a post transcriptional modification that occurs in all organisms and plays a crucial role in the stages of RNA life, closely related to many life processes. As one of the newly discovered modifications, N1-methyladenosine (m1A) plays an important role in gene expression regulation, closely related to the occurrence and development of diseases. However, due to the low abundance of m1A, verifying the associations between m1As and diseases through wet experiments requires a great quantity of manpower and resources. In this study, we proposed a computational method for predicting the associations of RNA methylation and disease based on graph convolutional network (RMDGCN) with attention mechanism. We build an adjacency matrix through the collected m1As and diseases associations, and use positive-unlabeled learning to increase the number of positive samples. By extracting the features of m1As and diseases, a heterogeneous network is constructed, and a GCN with attention mechanism is adopted to predict the associations between m1As and diseases. The experimental results indicate that under a 5-fold cross validation, RMDGCN is superior to other methods (AUC = 0.9892 and AUPR = 0.8682). In addition, case studies indicate that RMDGCN can predict the relationships between unknown m1As and diseases. In summary, RMDGCN is an effective method for predicting the associations between m1As and diseases.


Assuntos
Aprendizagem , Metilação de RNA , RNA/genética , Projetos de Pesquisa , Biologia Computacional , Algoritmos
8.
Mediators Inflamm ; 2024: 3938136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39381066

RESUMO

Purpose: Aloperine (ALO), an alkaloid isolated from Sophora alopecuroides L., possesses multiple pharmacological activities and holds a promise potential for the treatment of various clinical conditions, including skin hypersensitivity, cancer, and inflammatory disorders. The purpose of this study was to investigate the role of ALO in acetaminophen (N-acetyl-para-aminophenol (APAP))-induced acute liver injury and its underlying mechanisms. Materials and Methods: An animal model of acute liver injury was induced by intraperitoneal injection of APAP (150 mg/kg). Prior to APAP injection, ALO (40 mg/kg) was administered daily for 7 consecutive days. Serum alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase levels were then measured using an automated chemical analyzer. Histopathological changes were evaluated using hematoxylin and eosin staining. Oxidative stress levels were measured by detecting superoxide dismutase (SOD), glutathione (GSH), and malondialdehyde (MDA). Pro-inflammatory cytokines were detected in serum and liver tissues using ELISA and quantitative real-time polymerase chain reaction (q-PCR). The expression of members of the HMGB1/TLR4/NF-κB signaling pathway and NLRP3 inflammasome were determined by Western blot and/or q-PCR. In addition, the expression and location of NLRP3, cleaved caspase-1, high-mobility group box 1 (HMGB1), and phosphorylated p65 (p-p65) were detected by immunofluorescence. Results: Pretreatment with ALO significantly protected mice from APAP-induced acute liver injury, with decreased MDA content, and significantly increased GSH and SOD activities. Furthermore, ALO pretreatment reduced the release of pro-inflammatory cytokines (IL-1ß and TNF-α) and decreased the expression of caspase-1, cleaved caspase-1, and NLRP3. In addition, ALO pretreatment also inhibited the activation of the HMGB1/TLR4/NF-κB signaling pathway. Conclusion: Taken together, ALO can ameliorate APAP-induced acute liver injury by inhibiting oxidative stress, inflammation by inhibiting the HMGB1/TLR4/NF-κB, and NLRP3/inflammasome pathway.


Assuntos
Acetaminofen , Doença Hepática Induzida por Substâncias e Drogas , Proteína HMGB1 , Inflamassomos , NF-kappa B , Proteína 3 que Contém Domínio de Pirina da Família NLR , Piperidinas , Transdução de Sinais , Receptor 4 Toll-Like , Animais , Receptor 4 Toll-Like/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Camundongos , Acetaminofen/efeitos adversos , NF-kappa B/metabolismo , Masculino , Proteína HMGB1/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Inflamassomos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Fígado/efeitos dos fármacos , Fígado/metabolismo , Quinolizidinas
9.
Echocardiography ; 41(8): e15895, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39073188

RESUMO

Malignant melanoma (MM) is notorious for its high metastatic potential, with cardiac metastasis being particularly severe as it involves cardiac structures and can lead to significant cardiac functional issues. While there is no standardized treatment approach, early detection and intervention can improve prognosis.


Assuntos
Ecocardiografia , Neoplasias Cardíacas , Neoplasias Intestinais , Melanoma , Humanos , Melanoma/secundário , Neoplasias Cardíacas/secundário , Neoplasias Cardíacas/diagnóstico por imagem , Ecocardiografia/métodos , Neoplasias Intestinais/secundário , Neoplasias Intestinais/diagnóstico por imagem , Masculino , Intestino Delgado , Pessoa de Meia-Idade
10.
Echocardiography ; 41(7): e15874, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38924187

RESUMO

The combination of the right aortic arch and aberrant left subclavian artery (ALSA) with Kommerell's diverticulum (KD) is rare to coexist with the left innominate vein (LINV) beneath the aortic arch. It escalates the surgical risk undoubtedly and increases the difficulty of clinical procedures. We report one case diagnosed by Ultrasound and Computed Tomography Angiography (CTA).


Assuntos
Aorta Torácica , Veias Braquiocefálicas , Angiografia por Tomografia Computadorizada , Divertículo , Artéria Subclávia , Ultrassonografia , Humanos , Feminino , Gravidez , Adulto , Anormalidades Cardiovasculares/complicações , Aorta Torácica/anormalidades , Aorta Torácica/diagnóstico por imagem , Veias Braquiocefálicas/anormalidades , Veias Braquiocefálicas/diagnóstico por imagem , Aneurisma/complicações , Aneurisma/diagnóstico por imagem , Divertículo/complicações , Divertículo/diagnóstico por imagem , Artéria Subclávia/anormalidades , Artéria Subclávia/diagnóstico por imagem , Ecocardiografia , Diagnóstico Pré-Natal , Masculino , Recém-Nascido
11.
Echocardiography ; 41(5): e15826, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38678584

RESUMO

This case report describes a 35-year-old female patient who presented with palpitations and shortness of breath. Imaging findings suggested a cardiac tumor, histopathology confirmed primary cardiac angiosarcoma. This tumor is highly aggressive, usually occurs in the right atrium, lacks specificity in clinical presentation, is prone to early metastasis, and has a poor prognosis. Echocardiography is the method of choice for early detection and is important in assessing tumor size, location, mode of attachment and whether cardiac function is impaired.


Assuntos
Ecocardiografia , Neoplasias Cardíacas , Hemangiossarcoma , Humanos , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/diagnóstico , Feminino , Hemangiossarcoma/diagnóstico por imagem , Hemangiossarcoma/diagnóstico , Adulto , Ecocardiografia/métodos , Átrios do Coração/diagnóstico por imagem , Diagnóstico Diferencial
12.
Acta Biochim Biophys Sin (Shanghai) ; 56(3): 331-344, 2024 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-38327187

RESUMO

Atherosclerosis (AS), the main contributor to acute cardiovascular events, such as myocardial infarction and ischemic stroke, is characterized by necrotic core formation and plaque instability induced by cell death. The mechanisms of cell death in AS have recently been identified and elucidated. Ferroptosis, a novel iron-dependent form of cell death, has been proven to participate in atherosclerotic progression by increasing endothelial reactive oxygen species (ROS) levels and lipid peroxidation. Furthermore, accumulated intracellular iron activates various signaling pathways or risk factors for AS, such as abnormal lipid metabolism, oxidative stress, and inflammation, which can eventually lead to the disordered function of macrophages, vascular smooth muscle cells, and vascular endothelial cells. However, the molecular pathways through which ferroptosis affects AS development and progression are not entirely understood. This review systematically summarizes the interactions between AS and ferroptosis and provides a feasible approach for inhibiting AS progression from the perspective of ferroptosis.


Assuntos
Aterosclerose , Ferroptose , AVC Isquêmico , Humanos , Células Endoteliais , Ferro , Espécies Reativas de Oxigênio , Peroxidação de Lipídeos
13.
Proc Natl Acad Sci U S A ; 118(40)2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34583993

RESUMO

Dysregulation of ion and potential homeostasis in the scala media is the most prevalent cause of hearing loss in mammals. However, it is not well understood how the development and function of the stria vascularis regulates this fluid homeostasis in the scala media. From a mouse genetic screen, we characterize a mouse line, named 299, that displays profound hearing impairment. Histology suggests that 299 mutant mice carry a severe, congenital structural defect of the stria vascularis. The in vivo recording of 299 mice using double-barreled electrodes shows that endocochlear potential is abolished and potassium concentration is reduced to ∼20 mM in the scala media, a stark contrast to the +80 mV endocochlear potential and the 150 mM potassium concentration present in healthy control mice. Genomic analysis revealed a roughly 7-kb-long, interspersed nuclear element (LINE-1 or L1) retrotransposon insertion on chromosome 11. Strikingly, the deletion of this L1 retrotransposon insertion from chromosome 11 restored the hearing of 299 mutant mice. In summary, we characterize a mouse model that enables the study of stria vascularis development and fluid homeostasis in the scala media.


Assuntos
Surdez/genética , Retroelementos/genética , Estria Vascular/fisiologia , Animais , Cromossomos de Mamíferos/genética , Surdez/metabolismo , Surdez/fisiopatologia , Modelos Animais de Doenças , Feminino , Células Ciliadas Auditivas/fisiologia , Audição/genética , Perda Auditiva/genética , Perda Auditiva/fisiopatologia , Homeostase/genética , Homeostase/fisiologia , Potenciais da Membrana/genética , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Knockout , Potássio/metabolismo , Gravidez
14.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34244441

RESUMO

Ultrasonic hearing and vocalization are the physiological mechanisms controlling echolocation used in hunting and navigation by microbats and bottleneck dolphins and for social communication by mice and rats. The molecular and cellular basis for ultrasonic hearing is as yet unknown. Here, we show that knockout of the mechanosensitive ion channel PIEZO2 in cochlea disrupts ultrasonic- but not low-frequency hearing in mice, as shown by audiometry and acoustically associative freezing behavior. Deletion of Piezo2 in outer hair cells (OHCs) specifically abolishes associative learning in mice during hearing exposure at ultrasonic frequencies. Ex vivo cochlear Ca2+ imaging has revealed that ultrasonic transduction requires both PIEZO2 and the hair-cell mechanotransduction channel. The present study demonstrates that OHCs serve as effector cells, combining with PIEZO2 as an essential molecule for ultrasonic hearing in mice.


Assuntos
Células Ciliadas Auditivas Externas/metabolismo , Audição/fisiologia , Canais Iônicos/metabolismo , Ultrassom , Animais , Cálcio/metabolismo , Reação de Congelamento Cataléptica , Deleção de Genes , Células HEK293 , Humanos , Mecanotransdução Celular , Camundongos Knockout
15.
Ecotoxicol Environ Saf ; 283: 116786, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39083869

RESUMO

Cd ions are absorbed and transported from the soil by crop roots, which are the first organ to be exposed to Cd. This results in an increase in cadmium ions in crops, significantly affecting crop growth and yield. Exogenous melatonin (MT) can help reduce cadmium (Cd) stress in cotton, but the specific contribution of roots to this process remains unclear. In order to address this knowledge gap, an in-situ root phenotyping study was conducted to investigate the the phenotype and lifespan of roots under cadmium stress (Cd) and melatonin treatment (Cd + MT). The results showed that MT alleviated the decreases in plant height, leaf area, SPAD value, stem diameter, stomatal conductance and net photosynthetic rate under Cd stress, which further promoted the biomass accumulation in various cotton organs. What is more, the Cd + MT treatment increased root volume, surface area, and length under Cd stress by 25.63 %, 10.58 %, and 21.89 %, respectively, compared with Cd treatment. Interestingly, compared to Cd treatment, Cd + MT treatment also significantly extended the lifespan of roots and root hairs by 6.68 days and 2.18 days, respectively. In addition, Cd + MT treatment reduced the transport of Cd from roots to shoots, particularly to bolls, and decreased the Cd bioconcentration factor in bolls by 61.17 %, compared to Cd treatment. In conclusion, these findings show that applying MT externally helps reduce Cd stress by delaying root senescence, promoting root development and regulating Cd transport. This method can be an effective approach to managing Cd stress in cotton.


Assuntos
Cádmio , Gossypium , Melatonina , Raízes de Plantas , Poluentes do Solo , Gossypium/efeitos dos fármacos , Gossypium/crescimento & desenvolvimento , Melatonina/farmacologia , Cádmio/toxicidade , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Poluentes do Solo/toxicidade , Transporte Biológico/efeitos dos fármacos
16.
Phytother Res ; 38(7): 3564-3582, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38715375

RESUMO

Type 2 diabetes mellitus (T2DM), a metabolic disease with persistent hyperglycemia primarily caused by insulin resistance (IR), has become one of the most serious health challenges of the 21st century, with considerable economic and societal implications worldwide. Considering the inevitable side effects of conventional antidiabetic drugs, natural ingredients exhibit promising therapeutic efficacy and can serve as safer and more cost-effective alternatives for the management of T2DM. Saponins are a structurally diverse class of amphiphilic compounds widely distributed in many popular herbal medicinal plants, some animals, and marine organisms. There are many saponin monomers, such as ginsenoside compound K, ginsenoside Rb1, ginsenoside Rg1, astragaloside IV, glycyrrhizin, and diosgenin, showing great efficacy in the treatment of T2DM and its complications in vivo and in vitro. However, although the mechanisms of action of saponin monomers at the animal and cell levels have been gradually elucidated, there is a lack of clinical data, which hinders the development of saponin-based antidiabetic drugs. Herein, the main factors/pathways associated with T2DM and the comprehensive underlying mechanisms and potential applications of these saponin monomers in the management of T2DM and its complications are reviewed and discussed, aiming to provide fundamental data for future high-quality clinical studies and trials.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Saponinas , Diabetes Mellitus Tipo 2/tratamento farmacológico , Saponinas/farmacologia , Saponinas/química , Humanos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Animais , Plantas Medicinais/química , Resistência à Insulina
17.
Phytother Res ; 38(3): 1278-1293, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38191199

RESUMO

Chronic obstructive pulmonary disease (COPD) is a chronic, progressive, and lethal lung disease with few treatments. Formononetin (FMN) is a clinical preparation extract with extensive pharmacological actions. However, its effect on COPD remains unknown. This study aimed to explore the effect and underlying mechanisms of FMN on COPD. A mouse model of COPD was established by exposure to cigarette smoke (CS) for 24 weeks. In addition, bronchial epithelial BEAS-2B cells were treated with CS extract (CSE) for 24 h to explore the in vitro effect of FMN. FMN significantly improved lung function and attenuated pathological lung damage. FMN treatment reduced inflammatory cell infiltration and pro-inflammatory cytokines secretion. FMN also suppressed apoptosis by regulating apoptosis-associated proteins. Moreover, FMN relieved CS-induced endoplasmic reticulum (ER) stress in the mouse lungs. In BEAS-2B cells, FMN treatment reduced CSE-induced inflammation, ER stress, and apoptosis. Mechanistically, FMN downregulated the CS-activated AhR/CYP1A1 and AKT/mTOR signaling pathways in vivo and in vitro. FMN can attenuate CS-induced COPD in mice by suppressing inflammation, ER stress, and apoptosis in bronchial epithelial cells via the inhibition of AhR/CYP1A1 and AKT/mTOR signaling pathways, suggesting a new therapeutic potential for COPD treatment.


Assuntos
Fumar Cigarros , Isoflavonas , Doença Pulmonar Obstrutiva Crônica , Animais , Camundongos , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular , Citocromo P-450 CYP1A1 , Estresse do Retículo Endoplasmático , Células Epiteliais/metabolismo , Inflamação/metabolismo , Pulmão , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
18.
Mycopathologia ; 189(2): 28, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483684

RESUMO

BACKGROUND: Fungal keratitis (FK) is a kind of infectious keratopathy with a high rate of blindness worldwide. Deoxynivalenol (DON) has been proven to have multiple toxic effects on humans and animals. OBJECTIVES: The aim of this study was to explore a possible pathogenic role of DON in FK. METHODS: We first made an animal model of FK in New Zealand white rabbits, and then attempted to detect DON in a culture medium in which Fusarium solani had been grown and also in the corneal tissue of the animal model of Fusarium solani keratitis. Next, a model of DON damage in human corneal epithelial cells (HCECs) was constructed to evaluate effects of DON on the activity, migration ability, cell cycle, and apoptosis in the HCECs. Then, putative the toxic damaging effects of DON on rabbit corneal epithelial cells and the impact of the repair cycle were studied. The expression levels of inflammatory factors in the corneas of the animal model and in the model of DON-damaged HCECs were measured. RESULTS: The Fusarium solani strain used in this study appeared to have the potential to produce DON, since DON was detected in the corneal tissue of rabbits which had been inoculated with this Fusarium solani strain. DON was found to alter the morphology of HCECs, to reduce the activity and to inhibit the proliferation and migration of HCECs. DON also induced the apoptosis and S-phase arrest of HCECs. In addition, DON was found to damage rabbit corneal epithelial cells, to prolong the corneal epithelial regeneration cycle, and to be associated with the upregulated expression of inflammatory factors in HCECs and rabbit corneas. CONCLUSIONS: DON appears to have a toxic damaging effect on HCECs in FK, and to induce the expression of inflammatory factors, leading to the exacerbation of keratitis and the formation of new blood vessels. Future studies will explore the possibility of developing a test to detect DON in ophthalmic settings to aid the rapid diagnosis of FK, and to develop DON neutralizers and adsorbents which have the potential to improve keratocyte status, inhibit apoptosis, and alleviate inflammation, therein providing new thinking for therapy of clinical FK.


Assuntos
Úlcera da Córnea , Infecções Oculares Fúngicas , Fusarium , Ceratite , Tricotecenos , Humanos , Coelhos , Animais , Ceratite/microbiologia , Células Epiteliais
19.
J Clin Ultrasound ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248035

RESUMO

We report a case of a 65-year-old postmenopausal female patient who presented with 1 day of vaginal bleeding. Imaging studies diagnosed a uterine tumor lesion, and the patient underwent a total hysterectomy and bilateral salpingo-oophorectomy. The excised specimen was sent for pathological examination, and based on immunohistochemical analysis, the patient was ultimately diagnosed with Uterine tumor resembling ovarian sex cord tumor (UTROSCT). Postoperative adjuvant chemotherapy was administered, and the patient has been in good condition during the follow-up period.

20.
J Clin Ultrasound ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39239751

RESUMO

Malignant melanoma is a rare malignant tumor that can occur in many parts of the body. Primary vaginal malignant melanoma (PVMM) in women accounts for only 3%-7% of all malignant melanomas. PVMM is extremely rare, aggressive, and has a poor prognosis. We report a case of primary vaginal malignant melanoma in order to improve our understanding of the disease.

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