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1.
Proc Natl Acad Sci U S A ; 120(40): e2304096120, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37748052

RESUMO

Eight extant species of pangolins are currently recognized. Recent studies found that two mitochondrial haplotypes identified in confiscations in Hong Kong could not be assigned to any known pangolin species, implying the existence of a species. Here, we report that two additional mitochondrial haplotypes identified in independent confiscations from Yunnan align with the putative species haplotypes supporting the existence of this mysterious species/population. To verify the new species scenario we performed a comprehensive analysis of scale characteristics and 138 whole genomes representing all recognized pangolin species and the cryptic new species, 98 of which were generated here. Our morphometric results clearly attributed this cryptic species to Asian pangolins (Manis sp.) and the genomic data provide robust and compelling evidence that it is a pangolin species distinct from those recognized previously, which separated from the Philippine pangolin and Malayan pangolin over 5 Mya. Our study provides a solid genomic basis for its formal recognition as the ninth pangolin species or the fifth Asian one, supporting a new taxonomic classification of pangolins. The effects of glacial climate changes and recent anthropogenic activities driven by illegal trade are inferred to have caused its population decline with the genomic signatures showing low genetic diversity, a high level of inbreeding, and high genetic load. Our finding greatly expands current knowledge of pangolin diversity and evolution and has vital implications for conservation efforts to prevent the extinction of this enigmatic and endangered species from the wild.


Assuntos
Genômica , Pangolins , Animais , Efeitos Antropogênicos , Ásia , China , Pangolins/genética , Crescimento Demográfico
2.
Cell Mol Life Sci ; 81(1): 282, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943031

RESUMO

Cetuximab resistance has been a major challenge for head and neck squamous cell carcinoma (HNSCC) patients receiving targeted therapy. However, the mechanism that causes cetuximab resistance, especially microRNA (miRNA) regulation, remains unclear. Growing evidence suggests that miRNAs may act as "nuclear activating miRNAs" for targeting promoter regions or enhancers related to target genes. This study elucidates a novel mechanism underlying cetuximab resistance in HNSCC involving the nuclear activation of KDM7A transcription via miR-451a. Herein, small RNA sequencing, quantitative real-time polymerase chain reaction (qRT‒PCR) and fluorescence in situ hybridization (FISH) results provided compelling evidence of miR-451a nuclear enrichment in response to cetuximab treatment. Chromatin isolation via RNA purification, microarray analysis, and bioinformatic analysis revealed that miR-451a interacts with an enhancer region in KDM7A, activating its expression and further facilitating cetuximab resistance. It has also been demonstrated that the activation of KDM7A by nuclear miR-451a is induced by cetuximab treatment and is AGO2 dependent. Logistic regression analyses of 87 HNSCC samples indicated the significance of miR-451a and KDM7A in the development of cetuximab resistance. These discoveries support the potential of miR-451a and KDM7A as valuable biomarkers for cetuximab resistance and emphasize the function of nuclear-activating miRNAs.


Assuntos
Cetuximab , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço , MicroRNAs , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Cetuximab/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Animais , Camundongos , Núcleo Celular/metabolismo , Núcleo Celular/genética , Feminino , Camundongos Nus
3.
Proc Natl Acad Sci U S A ; 119(49): e2211429119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36442087

RESUMO

The current classification of acute myeloid leukemia (AML) relies largely on genomic alterations. Robust identification of clinically and biologically relevant molecular subtypes from nongenomic high-throughput sequencing data remains challenging. We established the largest multicenter AML cohort (n = 655) in China, with all patients subjected to RNA sequencing (RNA-Seq) and 619 (94.5%) to targeted or whole-exome sequencing (TES/WES). Based on an enhanced consensus clustering, eight stable gene expression subgroups (G1-G8) with unique clinical and biological significance were identified, including two unreported (G5 and G8) and three redefined ones (G4, G6, and G7). Apart from four well-known low-risk subgroups including PML::RARA (G1), CBFB::MYH11 (G2), RUNX1::RUNX1T1 (G3), biallelic CEBPA mutations or -like (G4), four meta-subgroups with poor outcomes were recognized. The G5 (myelodysplasia-related/-like) subgroup enriched clinical, cytogenetic and genetic features mimicking secondary AML, and hotspot mutations of IKZF1 (p.N159S) (n = 7). In contrast, most NPM1 mutations and KMT2A and NUP98 fusions clustered into G6-G8, showing high expression of HOXA/B genes and diverse differentiation stages, from hematopoietic stem/progenitor cell down to monocyte, namely HOX-primitive (G7), HOX-mixed (G8), and HOX-committed (G6). Through constructing prediction models, the eight gene expression subgroups could be reproduced in the Cancer Genome Atlas (TCGA) and Beat AML cohorts. Each subgroup was associated with distinct prognosis and drug sensitivities, supporting the clinical applicability of this transcriptome-based classification of AML. These molecular subgroups illuminate the complex molecular network of AML, which may promote systematic studies of disease pathogenesis and foster the screening of targeted agents based on omics.


Assuntos
Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Humanos , Transcriptoma , Leucemia Mieloide Aguda/genética , Diferenciação Celular/genética , Células-Tronco Hematopoéticas
4.
Nano Lett ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38913825

RESUMO

In the heterostructure of two-dimensional (2D) materials, many novel physics phenomena are strongly dependent on the Moiré superlattice. How to achieve the continuous manipulation of the Moiré superlattice in the same sample is very important to study the evolution of various physical properties. Here, in minimally twisted monolayer-multilayer graphene, we found that bubble-induced strain has a huge impact on the Moiré superlattice. By employing the AFM tip to dynamically and continuously move the nanobubble, we realized the modulation of the Moiré superlattice, like the evolution of regular triangular domains into long strip domain structures with single or double domain walls. We also achieved controllable modulation of the Moiré superlattice by moving multiple nanobubbles and establishing the coupling of nanobubbles. Our work presents a flexible method for continuous and controllable manipulation of Moiré superlattices, which will be widely used to study novel physical properties in 2D heterostructures.

5.
Anal Chem ; 96(2): 847-855, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38159051

RESUMO

RNA molecules undergo various chemical modifications that play critical roles in a wide range of biological processes. N6,N6-Dimethyladenosine (m6,6A) is a conserved RNA modification and is essential for the processing of rRNA. To gain a deeper understanding of the functions of m6,6A, site-specific and accurate quantification of this modification in RNA is indispensable. In this study, we developed an AlkB-facilitated demethylation (AD-m6,6A) method for the site-specific detection and quantification of m6,6A in RNA. The N6,N6-dimethyl groups in m6,6A can cause reverse transcription to stall at the m6,6A site, resulting in truncated cDNA. However, we found that Escherichia coli AlkB demethylase can effectively demethylate m6,6A in RNA, generating full-length cDNA from AlkB-treated RNA. By quantifying the amount of full-length cDNA produced using quantitative real-time PCR, we were able to achieve site-specific detection and quantification of m6,6A in RNA. Using the AD-m6,6A method, we successfully detected and quantified m6,6A at position 1851 of 18S rRNA and position 937 of mitochondrial 12S rRNA in human cells. Additionally, we found that the level of m6,6A at position 1007 of mitochondrial 12S rRNA was significantly reduced in lung tissues from sleep-deprived mice compared with control mice. Overall, the AD-m6,6A method provides a valuable tool for easy, accurate, quantitative, and site-specific detection of m6,6A in RNA, which can aid in uncovering the functions of m6,6A in human diseases.


Assuntos
Proteínas de Escherichia coli , RNA , Humanos , Animais , Camundongos , RNA/química , Adenosina/química , DNA Complementar , Metilação , Escherichia coli/genética , Escherichia coli/metabolismo , Desmetilação , Oxigenases de Função Mista
6.
Anal Chem ; 96(11): 4726-4735, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38450632

RESUMO

DNA cytosine methylation (5-methylcytosine, 5mC) is a predominant epigenetic modification that plays a critical role in a variety of biological and pathological processes in mammals. In active DNA demethylation, the 10-11 translocation (TET) dioxygenases can sequentially oxidize 5mC to generate three modified forms of cytosine, 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC). Beyond being a demethylation intermediate, recent studies have shown that 5fC has regulatory functions in gene expression and chromatin organization. While some methods have been developed to detect 5fC, genome-wide mapping of 5fC at base resolution is still highly desirable. Herein, we propose a chemical labeling enrichment and deamination sequencing (CLED-seq) method for detecting 5fC in genomic DNA at single-base resolution. The CLED-seq method utilizes selective labeling and enrichment of 5fC-containing DNA fragments, followed by deamination mediated by apolipoprotein B mRNA-editing catalytic polypeptide-like 3A (APOBEC3A or A3A) and sequencing. In the CLED-seq process, while all C, 5mC, and 5hmC are interpreted as T during sequencing, 5fC is still read as C, enabling the precise detection of 5fC in DNA. Using the proposed CLED-seq method, we accomplished genome-wide mapping of 5fC in mouse embryonic stem cells. The mapping study revealed that promoter regions enriched with 5fC overlapped with H3K4me1, H3K4me3, and H3K27ac marks. These findings suggest a correlation between 5fC marks and active gene expression in mESCs. In conclusion, CLED-seq is a straightforward, bisulfite-free method that offers a valuable tool for detecting 5fC in genomes at a single-base resolution.


Assuntos
Citidina Desaminase , Citosina , Citosina/análogos & derivados , Epigênese Genética , Proteínas , Animais , Camundongos , Desaminação , Citosina/metabolismo , 5-Metilcitosina/metabolismo , Mapeamento Cromossômico , DNA/genética , DNA/metabolismo , Metilação de DNA , Mamíferos/metabolismo
7.
Small ; : e2311351, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453673

RESUMO

Supramolecular self-assembly has emerged as an efficient tool to construct well-organized nanostructures for biomedical applications by small organic molecules. However, the physicochemical properties of self-assembled nanoarchitectures are greatly influenced by their morphologies, mechanical properties, and working mechanisms, making it challenging to design and screen ideal building blocks. Herein, using a biocompatible firefly-sourced click reaction between the cyano group of 2-cyano-benzothiazole (CBT) and the 1,2-aminothiol group of cysteine (Cys), an amino-acid-encoded supramolecular self-assembly platform Cys(SEt)-X-CBT (X represents any amino acid) is developed to incorporate both covalent and noncovalent interactions for building diverse morphologies of nanostructures with bioinspired response mechanism, providing a convenient and rapid strategy to construct site-specific nanocarriers for drug delivery, cell imaging, and enzyme encapsulation. Additionally, it is worth noting that the biodegradation of Cys(SEt)-X-CBT generated nanocarriers can be easily tracked via bioluminescence imaging. By caging either the thiol or amino groups in Cys with other stimulus-responsive sites and modifying X with probes or drugs, a variety of multi-morphological and multifunctional nanomedicines can be readily prepared for a wide range of biomedical applications.

8.
Opt Express ; 32(6): 10419-10428, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571254

RESUMO

Twisted stacking of two-dimensional materials with broken inversion symmetry, such as spiral MoTe2 nanopyramids and supertwisted spiral WS2, emerge extremely strong second- and third-harmonic generation. Unlike well-studied nonlinear optical effects in these newly synthesized layered materials, photoluminescence (PL) spectra and exciton information involving their optoelectronic applications remain unknown. Here, we report layer- and power-dependent PL spectra of the supertwisted spiral WS2. The anomalous layer-dependent PL evolutions that PL intensity almost linearly increases with the rise of layer thickness have been determined. Furthermore, from the power-dependent spectra, we find the power exponents of the supertwisted spiral WS2 are smaller than 1, while those of the conventional multilayer WS2 are bigger than 1. These two abnormal phenomena indicate the enlarged interlayer spacing and the decoupling interlayer interaction in the supertwisted spiral WS2. These observations provide insight into PL features in the supertwisted spiral materials and may pave the way for further optoelectronic devices based on the twisted stacking materials.

9.
FASEB J ; 37(6): e22936, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37144417

RESUMO

The tumor suppressor p53 has been implicated in the pathogenesis of liver fibrosis. HERC5-mediated posttranslational ISG modification of the p53 protein is critical for controlling its activity. Here, we demonstrated that the expression of HERC5 and ISG15 is highly elevated, whereas p53 is downregulated, in fibrotic liver tissues of mice and transforming growth factor-ß1 (TGF-ß1)-induced LX2 cells. HERC5 siRNA clearly increased the protein expression of p53, but the mRNA expression of p53 was not obviously changed. The inhibition of lincRNA-ROR (ROR) downregulated HERC5 expression and elevated p53 expression in TGF-ß1-stimulated LX-2 cells. Furthermore, the expression of p53 was almost unchanged after TGF-ß1-stimulated LX-2 cells were co-transfected with a ROR-expressing plasmid and HERC5 siRNA. We further confirmed that miR-145 is a target gene of ROR. In addition, we also showed that ROR regulates the HERC5-mediated ISGylation of p53 through mir-145/ZEB2. Together, we propose that ROR/miR-145/ZEB2 might be involved in the course of liver fibrosis by regulating ISGylation of the p53 protein.


Assuntos
MicroRNAs , RNA Longo não Codificante , Humanos , Fator de Crescimento Transformador beta1/metabolismo , RNA Longo não Codificante/genética , Cirrose Hepática/metabolismo , Fibrose , RNA Interferente Pequeno , MicroRNAs/genética , Peptídeos e Proteínas de Sinalização Intracelular , Homeobox 2 de Ligação a E-box com Dedos de Zinco
10.
Inorg Chem ; 63(11): 5076-5082, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38447153

RESUMO

Herein, two Laves intermetallic series, ZrCo1.75M0.25 and NbCo1.75M0.25 (M = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, and Pt), were synthesized, and their hydrogen evolution reaction (HER) activities were examined to reveal the influence of d electrons to the corresponding HER activities. Owing to the different electronegativity between Zr and Nb (χZr = 1.33; χNb = 1.60), Co and/or M elements receive more electrons in ZrCo1.75M0.25 than that of the Nb one. This leads to the overall weak H adsorption energy (ΔGHad) of ZrCo1.75M0.25 series compared to that of NbCo1.75M0.25 and rationalizes well the superior HER activity of the Rh member compared to that of the Pt one in the ZrCo1.75M0.25 series. Under industrial conditions (333 K, 6.0 M KOH), ZrCo1.75Rh0.25 only requires an overpotential of 110 mV to reach the current density of 500 mA/cm2 and can be operated at high current density over 400 h. This work demonstrates that with a proper combination between elements in intermetallic phases, one can manipulate d electrons of the active metal to be closer to the sweet spot (ΔGHad = 0). The Pt member may no longer exhibit the best HER activity in series, and all elements exhibit the potential to outperform the Pt member in the HER with careful control of the d electron population.

11.
J Peripher Nerv Syst ; 29(1): 107-110, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38329138

RESUMO

BACKGROUND AND AIMS: The parent-proxy reports can offer complementary informations or be the only source of Quality of Life measurement in young children. The aim of this study was to provide and validate the Italian version of the recently published parent-proxy pCMT-QOL for patients aged 8-18 years old, making it available for possible trials in Italian speaking children. METHODS: The English-language instrument was translated and adapted into the Italian language using standard procedures: translation, transcultural adaptation, and back-translation. Parent-proxy pCMT-QOL was administered to parents of patients with a genetic diagnosis of CMT, aged 8-18 years old. All parents were retested 2 weeks later to assess reliability. RESULTS: A total of 21 parents of CMT patients (18 CMT1A, 2 CMT2A, 1 CMT2K) were assessed during their children clinical appointments. The Italian-pCMT-QOL showed a high test-retest reliability; none of the parents had any difficulties with the completion of the questionnaire and no further revisions were necessary after completion. INTERPRETATION: The Italian parent-proxy pCMT-QOL is a reliable, culturally adapted, and comparable version of the original English instrument. This questionnaire will improve the quality of the follow-up and will make it possible to monitor more accurately the severity of the disease in Italian-speaking families.


Assuntos
Pais , Qualidade de Vida , Humanos , Criança , Pré-Escolar , Adolescente , Reprodutibilidade dos Testes , Inquéritos e Questionários , Idioma , Itália , Psicometria
12.
Brain ; 146(9): 3826-3835, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36947133

RESUMO

Recessive SH3TC2 variants cause Charcot-Marie-Tooth disease type 4C (CMT4C). CMT4C is typically a sensorimotor demyelinating polyneuropathy, marked by early onset spinal deformities, but its clinical characteristics and severity are quite variable. Clear relationships between pathogenic variants and the spectrum of disease manifestations are to date lacking. Gene replacement therapy has been shown to ameliorate the phenotype in a mouse model of CMT4C, emphasizing the need for natural history studies to inform clinical trial readiness. Data, including both genetic information and clinical characteristics, were compiled from the longitudinal, prospective dataset of the Inherited Neuropathy Consortium, a member of the Rare Diseases Clinical Research Network (INC-RDCRN). The Charcot Marie Tooth Neuropathy Score (CMTNS), Examination Score (CMTES) and the Rasch-weighted CMTES (CMTES-R) were used to describe symptoms, neurological examinations and neurophysiological characteristics. Standardized response means were calculated at yearly intervals and a mixed model for repeated measures was used to estimate the change in CMTES and CMTES-R over time. Fifty-six individuals (59% female), median age 27 years (range 2-67 years) with homozygous or compound heterozygous variants in SH3TC2 were identified, including 34 unique variants, 14 of which have not previously been published. Twenty-eight participants had longitudinal data available. While there was no significant difference in the CMTES in those with protein truncating versus non-protein truncating variants, there were significant differences in the mean ulnar nerve compound muscle action potential amplitude, the mean radial sensory nerve action potential amplitude, and in the prevalence of scoliosis, suggesting the possibility of a milder phenotype in individuals with one or two non-protein-truncating variants. Overall, the mean value of the CMTES was 13, reflecting moderate clinical severity. There was a high rate of scoliosis (81%), scoliosis surgery (36%), and walking difficulty (94%) among study participants. The CMTES and CMTES-R appeared moderately responsive to change over extended follow-up, demonstrating a standardized response mean of 0.81 standard deviation units or 0.71 standard deviation units, respectively, over 3 years. Our analysis represents the largest cross-sectional and only longitudinal study to date, of the clinical phenotype of both adults and children with CMT4C. With the promise of upcoming genetic treatments, these data will further define the natural history of the disease and inform study design in preparation for clinical trials.


Assuntos
Escoliose , Animais , Camundongos , Feminino , Masculino , Escoliose/genética , Estudos Longitudinais , Mutação/genética , Estudos Transversais , Estudos Prospectivos , Estudos de Associação Genética
13.
Bioorg Chem ; 147: 107377, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38653150

RESUMO

The first systematic acylated diversification of naturally scarce premyrsinane diterpenes, together with their biosynthetic precursors lathyrane diterpene were carried out. Two new series of premyrsinane derivates (1a-32a) and lathyrane derivates (1-32) were synthesized from the naturally abundant lathyrane diterpene Euphorbia factor L3 through a bioinspired approach. The cholinesterase inhibitory and neuroprotective activities of these diterpenes were investigated to explore potential anti-Alzheimer's disease (AD) bioactive lead compounds. In general, the lathyrane diterpenes showed the better acetylcholinesterase (AChE) inhibitory activity than that of premyrsinanes. The lathyrane derivative 17 bearing a 3-dimethylaminobenzoyl moiety showed the best AChE inhibition effect with the IC50 value of 7.1 µM. Molecular docking demonstrated that 17 could bond with AChE well (-8 kal/mol). On the other hand, premyrsinanes showed a better neuroprotection profile against H2O2-induced injury in SH-SY5Y cells. Among them, the premyrsinane diterpene 16a had significant neuroprotective effect with the cell viability rate of 113.5 % at 12.5 µM (the model group with 51.2 %). The immunofluorescence, western blot and reactive oxygen species (ROS) analysis were conducted to demonstrate the mechanism of 16a. Furthermore, a preliminary SAR analysis of the two categories of diterpenes was performed to provide the insights for anti-AD drug development.


Assuntos
Acetilcolinesterase , Doença de Alzheimer , Inibidores da Colinesterase , Diterpenos , Euphorbia , Fármacos Neuroprotetores , Diterpenos/farmacologia , Diterpenos/química , Diterpenos/síntese química , Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/síntese química , Euphorbia/química , Humanos , Acetilcolinesterase/metabolismo , Relação Estrutura-Atividade , Estrutura Molecular , Simulação de Acoplamento Molecular , Relação Dose-Resposta a Droga , Sobrevivência Celular/efeitos dos fármacos
14.
Nature ; 556(7700): 255-258, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618817

RESUMO

Cross-species transmission of viruses from wildlife animal reservoirs poses a marked threat to human and animal health 1 . Bats have been recognized as one of the most important reservoirs for emerging viruses and the transmission of a coronavirus that originated in bats to humans via intermediate hosts was responsible for the high-impact emerging zoonosis, severe acute respiratory syndrome (SARS) 2-10 . Here we provide virological, epidemiological, evolutionary and experimental evidence that a novel HKU2-related bat coronavirus, swine acute diarrhoea syndrome coronavirus (SADS-CoV), is the aetiological agent that was responsible for a large-scale outbreak of fatal disease in pigs in China that has caused the death of 24,693 piglets across four farms. Notably, the outbreak began in Guangdong province in the vicinity of the origin of the SARS pandemic. Furthermore, we identified SADS-related CoVs with 96-98% sequence identity in 9.8% (58 out of 591) of anal swabs collected from bats in Guangdong province during 2013-2016, predominantly in horseshoe bats (Rhinolophus spp.) that are known reservoirs of SARS-related CoVs. We found that there were striking similarities between the SADS and SARS outbreaks in geographical, temporal, ecological and aetiological settings. This study highlights the importance of identifying coronavirus diversity and distribution in bats to mitigate future outbreaks that could threaten livestock, public health and economic growth.


Assuntos
Alphacoronavirus/isolamento & purificação , Alphacoronavirus/patogenicidade , Doenças dos Animais/epidemiologia , Doenças dos Animais/virologia , Quirópteros/virologia , Infecções por Coronavirus/veterinária , Diarreia/veterinária , Suínos/virologia , Alphacoronavirus/classificação , Alphacoronavirus/genética , Doenças dos Animais/transmissão , Animais , Biodiversidade , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Diarreia/patologia , Diarreia/virologia , Reservatórios de Doenças/veterinária , Reservatórios de Doenças/virologia , Genoma Viral/genética , Humanos , Jejuno/patologia , Jejuno/virologia , Filogenia , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/veterinária , Síndrome Respiratória Aguda Grave/virologia , Análise Espaço-Temporal , Zoonoses/epidemiologia , Zoonoses/transmissão , Zoonoses/virologia
15.
BMC Ophthalmol ; 24(1): 66, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355462

RESUMO

BACKGROUND: Iridoschisis is a rare condition that primarily affects individuals aged 60-70 years. The predominant characteristics of iridoschisis involve the tissue splitting and separation of the iris stromal layers, often resulting in two distinct layers and the presence of floating fibers in the anterior chamber. This article reports the case of a 48-year-old male with iridoschisis with partial lens dislocation in both eyes. CASE PRESENTATION: Trauma is the leading factor in the development of iridoschisis. However, there is no documented case of ocular trauma in the patient's medical history. Visible white atrophic fibers were observed bilaterally in the anterior iris stroma of both eyes of the individual, accompanied by a small quantity of iris tissue within the anterior chamber. In this instance, the magnitude of the iridoschisis corresponded with the degree of lens dislocation. We were apprised that the patient had regularly used a cervical massager for a prolonged period of time, positioning it upon the ocular region. Frequent stimulation of both eyes with excessive force resulted in the development of iridoschisis and the partial dislocation of the lens.During the initial surgical procedure, phacoemulsification (Phaco) was carried out on the left eye without the placement of an intraocular lens (IOL). Following a two-month interval, we proceeded with the IOL suspension. Subsequently, the right eye underwent Phaco, accompanied by the implantation of an IOL. After closely monitoring the patient's progress for two months, it was evident that their vision had significantly improved, substantiating the success of the surgical interventions. CONCLUSIONS: This finding posits that the recurrent friction applied to both eyes may induce iridoschisis and various ocular complications. In the event of ocular intricacies manifesting, expeditious medical intervention becomes imperative.


Assuntos
Extração de Catarata , Doenças da Íris , Subluxação do Cristalino , Lentes Intraoculares , Facoemulsificação , Masculino , Humanos , Pessoa de Meia-Idade , Doenças da Íris/diagnóstico , Doenças da Íris/cirurgia , Iris/cirurgia , Facoemulsificação/métodos , Subluxação do Cristalino/diagnóstico , Subluxação do Cristalino/etiologia , Subluxação do Cristalino/cirurgia
16.
World J Surg Oncol ; 22(1): 79, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486308

RESUMO

BACKGROUND: For women diagnosed with HR-HPV DNA positivity in community hospitals, the necessity of investigating the potential presence of multiple HR-HPV infections upon referral to tertiary medical institutions remains unclear. METHODS: In our cohort, women tested positive for HR-HPV DNA during examinations in community hospitals, were subsequently referred to tertiary medical facilities, reevaluated HR-HPV genotype and categorized based on cytological and histopathological results. The risk of cytologic/histopathology abnormalities and ≧ high grade squamous intraepithelial lesion(HSIL) or Cervical Intraepithelial Neoplasia (CIN) 2 associated with individual genotypes and related multiple HPV infections are calculated. RESULTS: A total of 1677 women aged between 21 and 77 were finally included in the present study. The cytology group included 1202 women and the histopathological group included 475 women with at least one HR-HPV infection of any genotype. We only observed a higher risk of low grade cytological abnormalities in women with multiple infections than those in corresponding single infections (for all population with an OR of 1.85[1.39-2.46]; p < 0.05). However, this phenomenon was not observed in histopathology abnormalities (CIN1). The risk of developing of ≥ HSIL/CIN2 in women who were infected with multiple HR-HPV also showed a similar profile to those with a single HR-HPV genotype. CONCLUSION: Multiple HR-HPV infections is only associated with a higher associated risk of low grade cytological abnormalities. There is no evidence of clinical benefit to identify the possible presence of multiple HR-HPV infection frequently in a short period of time for women with HR-HPV-DNA positive.


Assuntos
Carcinoma in Situ , Carcinoma de Células Escamosas , Infecções por Papillomavirus , Humanos , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Colo do Útero , Infecções por Papillomavirus/complicações , DNA
17.
Proc Natl Acad Sci U S A ; 118(25)2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34161288

RESUMO

The type 6 secretion system (T6SS) is a bacterial weapon broadly distributed in gram-negative bacteria and used to kill competitors and predators. Featuring a long and double-tubular structure, this molecular machine is energetically costly to produce and thus is likely subject to diverse regulation strategies that are largely ill defined. In this study, we report a quantity-sensing control of the T6SS that down-regulates the expression of secreted components when they accumulate in the cytosol due to T6SS inactivation. Using Vibrio cholerae strains that constitutively express an active T6SS, we demonstrate that mRNA levels of secreted components, including the inner-tube protein component Hcp, were down-regulated in T6SS structural gene mutants while expression of the main structural genes remained unchanged. Deletion of both hcp gene copies restored expression from their promoters, while Hcp overexpression negatively impacted expression. We show that Hcp directly interacts with the RpoN-dependent T6SS regulator VasH, and deleting the N-terminal regulator domain of VasH abolishes this interaction as well as the expression difference of hcp operons between T6SS-active and inactive strains. We find that negative regulation of hcp also occurs in other V. cholerae strains and the pathogens Aeromonas dhakensis and Pseudomonas aeruginosa This Hcp-dependent sensing control is likely an important energy-conserving mechanism that enables T6SS-encoding organisms to quickly adjust T6SS expression and prevent wasteful build-up of its major secreted components in the absence of their efficient export out of the bacterial cell.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas Hemolisinas/metabolismo , Espaço Intracelular/metabolismo , Sistemas de Secreção Tipo VI/metabolismo , Vibrio cholerae/metabolismo , Proteínas de Bactérias/química , Citoplasma/metabolismo , Regulação para Baixo , Retroalimentação Fisiológica , Modelos Biológicos , Filogenia , Domínios Proteicos
18.
Nano Lett ; 23(10): 4101-4110, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37183806

RESUMO

Osteoporosis is a global disease caused by abnormal overactivation of osteoclasts. The acidic environment in sealing zone of osteoclasts with H+ pumped from cytoplasm is critical to the maturation of osteoclasts. Therefore, reducing the intracellular H+ concentration can reduce the H+ secretion of osteoclasts from the source. In our study, we developed a novel nanovesicle which encapsulates Na2HPO4 with a liposome hybridizes with preosteoclast membrane (Na2HPO4@Lipo-pOCm). These nanovesicles release Na2HPO4 into the preosteoclast by targeting preosteoclasts and membrane fusion, reducing the intracellular H+ concentration, and achieve biological cascade regulation of osteoclasts through simple pH regulation. In vitro and in vivo experiments confirmed that these nanovesicles reduce mitochondrial membrane potential by decreasing intracellular H+ concentration, thereby reducing the ROS in osteoclasts as well as the expression of the upstream transcription factor FOXM1 of Acp5. In short, this nanovesicle can significantly inhibit the osteoclasts and ameliorate osteoporosis caused by OVX.


Assuntos
Osteoclastos , Osteoporose , Humanos , Concentração de Íons de Hidrogênio , Homeostase
19.
J Bacteriol ; 205(2): e0035622, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36655996

RESUMO

Widely employed by Gram-negative pathogens for competition and pathogenesis, the type six protein secretion system (T6SS) can inject toxic effectors into neighboring cells through the penetration of a spear-like structure comprising a long Hcp tube and a VgrG-PAAR spike complex. The cone-shaped PAAR is believed to sharpen the T6SS spear for penetration but it remains unclear why PAAR is required for T6SS functions in some bacteria but dispensable in others. Here, we report the conditional requirement of PAAR for T6SS functions in Aeromonas dhakensis, an emerging human pathogen that may cause severe bacteremia. By deleting the two PAAR paralogs, we show that PAAR is not required for T6SS secretion, bacterial killing, or specific effector delivery in A. dhakensis. By constructing combinatorial PAAR and vgrG deletions, we demonstrate that deletion of individual PAAR moderately reduced T6SS functions but double or triple deletions of PAAR in the vgrG deletion mutants severely impaired T6SS functions. Notably, the auxiliary-cluster-encoded PAAR2 and VgrG3 are less critical than the main-cluster-encoded PAAR1 and VgrG1&2 proteins to T6SS functions. In addition, PAAR1 but not PAAR2 contributes to antieukaryotic virulence in amoeba. Our data suggest that, for a multi-PAAR T6SS, the variable role of PAAR paralogs correlates with the VgrG-spike composition that collectively dictates T6SS assembly. IMPORTANCE Gram-negative bacteria often encode multiple paralogs of the cone-shaped PAAR that sits atop the VgrG-spike and is thought to sharpen the spear-like T6SS puncturing device. However, it is unclear why PAAR is required for the assembly of some but not all T6SSs and why there are multiple PAARs if they are not required. Our data delineate a VgrG-mediated conditional requirement for PAAR and suggest a core-auxiliary relationship among different PAAR-VgrG modules that may have been acquired sequentially by the T6SS during evolution.


Assuntos
Sistemas de Secreção Tipo VI , Humanos , Sistemas de Secreção Tipo VI/metabolismo , Proteínas de Bactérias/metabolismo , Virulência
20.
Int J Cancer ; 152(1): 31-41, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35484979

RESUMO

Currently, the prognosis assessment of stage II colorectal cancer (CRC) remains a difficult clinical problem; therefore, more accurate prognostic predictors must be developed. In our study, we developed a prognostic prediction model for stage II CRC by fusing radiomics and deep-learning (DL) features of primary lesions and peripheral lymph nodes (LNs) in computed tomography (CT) scans. First, two CT radiomics models were built using primary lesion and LN image features. Subsequently, an information fusion method was used to build a fusion radiomics model by combining the tumor and LN image features. Furthermore, a transfer learning method was applied to build a deep convolutional neural network (CNN) model. Finally, the prediction scores generated by the radiomics and CNN models were fused to improve the prognosis prediction performance. The disease-free survival (DFS) and overall survival (OS) prediction areas under the curves (AUCs) generated by the fusion model improved to 0.76 ± 0.08 and 0.91 ± 0.05, respectively. These were significantly higher than the AUCs generated by the models using the individual CT radiomics and deep image features. Applying the survival analysis method, the DFS and OS fusion models yielded concordance index (C-index) values of 0.73 and 0.9, respectively. Hence, the combined model exhibited good predictive efficacy; therefore, it could be used for the accurate assessment of the prognosis of stage II CRC patients. Moreover, it could be used to screen out high-risk patients with poor prognoses, and assist in the formulation of clinical treatment decisions in a timely manner to achieve precision medicine.


Assuntos
Neoplasias Colorretais , Aprendizado Profundo , Humanos , Metástase Linfática/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Prognóstico , Tomografia Computadorizada por Raios X/métodos , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/patologia , Estudos Retrospectivos
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