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1.
Cereb Cortex ; 33(5): 1693-1707, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-35512682

RESUMO

Establishing neuronal circuits requires interactions between pre- and postsynaptic neurons. While presynaptic neurons were shown to play instructive roles for the postsynaptic neurons, how postsynaptic neurons provide feedback to regulate the presynaptic neuronal development remains elusive. To elucidate the mechanisms for circuit formation, we study the development of barrel cortex (the primary sensory cortex, S1), whose development is instructed by presynaptic thalamocortical axons (TCAs). In the first postnatal weeks, TCA terminals arborize in layer (L) 4 to fill in the barrel center, but it is unclear how TCA development is regulated. Here, we reported that the deletion of Lhx2 specifically in the cortical neurons in the conditional knockout (cKO) leads to TCA arborization defects, which is accompanied with deficits in sensory-evoked and spontaneous cortical activities and impaired lesion-induced plasticity following early whisker follicle ablation. Reintroducing Lhx2 back in L4 neurons in cKO ameliorated TCA arborization and plasticity defects. By manipulating L4 neuronal activity, we further demonstrated that Lhx2 induces TCA arborization via an activity-dependent mechanism. Additionally, we identified the extracellular signaling protein Sema7a as an activity-dependent downstream target of Lhx2 in regulating TCA branching. Thus, we discovered a bottom-up feedback mechanism for the L4 neurons to regulate TCA development.


Assuntos
Neurônios , Tálamo , Retroalimentação , Tálamo/fisiologia , Neurônios/fisiologia , Axônios/fisiologia , Transdução de Sinais , Córtex Somatossensorial/fisiologia
2.
Exp Mol Pathol ; : 104806, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35798064

RESUMO

SHARPIN (Shank-associated RH domain interacting protein) plays an important role in tumorigenesis. However, its role in ovarian cancer remains largely unknown. To investigate this issue, we systematically analyzed the amplification and expression of the SHARPIN in the TCGA database. From the database, we found that SHARPIN was amplified in ovarian cancer compared to normal ovarian tissue, and the mRNA level of SHARPIN was significantly elevated in ovarian cancer compared to non-tumorigenic ovarian tissue. In addition, we observed similar results from ovarian cancer cell lines and clinical samples from ovarian cancer patients, which indicated that increased SHARPIN expression is associated with tumorigenesis in ovarian cancer. SHARPIN knockdown inhibited the migration and invasion of ovarian cancer cells, also inhibited cell cycle and promoted apoptosis, thereby suppressing cell proliferation. RNA-seq results showed that SHARPIN significantly increased the expression of P53 and P21 and decreased the expression of Cyclin D1 and c-Myc, all of which are involved in the regulation of cell proliferation. Subsequent mechanistic exploration revealed that SHARPIN knockdown increased the expression of caspases 3 and 9, leading to apoptosis of ovarian cancer cells. We also found that high expression of SHARPIN was associated with poor prognosis of ovarian cancer patients. Collectively, we demonstrated a positive correlation between SHARPIN and ovarian cancer progression and provide a basis for combined targeted therapy strategies for future ovarian cancer treatment.

3.
Mol Ther ; 29(1): 396-408, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-32950103

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disorder leading to dementia in the elderly, and the mechanisms of AD are not fully defined. MicroRNAs (miRNAs) have been shown to contribute to memory deficits in AD. In this study, we identified that miR-204-3p was downregulated in the hippocampus and plasma of 6-month-old APPswe/PS1dE9 (APP/PS1) mice. miR-204-3p overexpression attenuated memory and synaptic deficits in APP/PS1 mice. The amyloid levels and oxidative stress were decreased in the hippocampus of APP/PS1 mice after miR-204-3p overexpression. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (Nox4) was a target of miR-204-3p, and Nox4 inhibition by GLX351322 protected neuronal cells against Aß1-42-induced neurotoxicity. Furthermore, GLX351322 treatment rescued synaptic and memory deficits, and decreased oxidative stress and amyloid levels in the hippocampus of APP/PS1 mice. These results revealed that miR-204-3p attenuated memory deficits and oxidative stress in APP/PS1 mice by targeting Nox4, and miR-204-3p overexpression and/or Nox4 inhibition might be a potential therapeutic strategy for AD treatment.


Assuntos
Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Transtornos da Memória/etiologia , MicroRNAs/genética , NADPH Oxidase 4/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Biomarcadores , Modelos Animais de Doenças , Suscetibilidade a Doenças , Transtornos da Memória/diagnóstico , Camundongos , Camundongos Transgênicos , Estresse Oxidativo
4.
J Therm Biol ; 105: 103220, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35393054

RESUMO

Heat stress causes economic loss of livestock industry in tropical areas. Exploring genetic markers for selection of thermotolerance will benefit chicken production. Oxidative stress and fluid-salt balance are tightly associated with thermotolerance and productivity in domestic animals. The study aimed to identify single-nucleotide polymorphisms (SNPs) in genes related to oxidative stress and ion-channel regulation and their associations with semen quality and hormonal responses. In total, 28 SNPs within 11 candidate genes were identified to associate with hormonal changes and semen quality in both broiler- and layer-type Taiwan country chickens (TCCs) after exposure to acute heat stress at 38 °C for 4 h. Acute heat stress significantly affected plasma levels of triiodothyronine and corticosterone and reduced sperm motility, viability, and concentrations in both strains at Day 1 after exposure. In the B-strain TCCs, five SNPs within NDUFA8 and DAB2IP had significant effects on plasma adrenaline and corticosterone levels, and six SNPs within TRPC1, SLC9A9, and TRPC7 markedly affected plasma corticosterone and triiodothyronine levels. In the L2 strain, 15 SNPs within PSMA2, TPK1, MTF1, and CUL1 exerted effects on plasma corticosterone and triiodothyronine levels. Five SNPs within CUL3, TRPC1, and SLC9A9 in the B strain and two SNPs within MTF1 in the L2 strain were associated with sperm concentrations at Day 1 after exposure to heat stress. In conclusion, acute heat stress impaired semen quality and altered plasma corticosterone and triiodothyronine levels in TCCs. Some SNPs involved in oxidative stress and ion-channel regulation were identified to associate with the hormonal and semen alterations. These SNPs in conjunction with differential hormonal responses and semen quality serve as genetic markers for thermotolerance selection in sire lines of chickens.


Assuntos
Galinhas , Transtornos de Estresse por Calor , Animais , Masculino , Galinhas/genética , Corticosterona , Marcadores Genéticos , Transtornos de Estresse por Calor/veterinária , Estresse Oxidativo , Polimorfismo de Nucleotídeo Único , Análise do Sêmen , Motilidade dos Espermatozoides , Tri-Iodotironina
5.
Cereb Cortex ; 30(5): 3015-3029, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31838488

RESUMO

Establishing a balance between excitation and inhibition is critical for brain functions. However, how inhibitory interneurons (INs) generated in the ventral telencephalon integrate with the excitatory neurons generated in the dorsal telencephalon remains elusive. Previous studies showed that INs migrating tangentially to enter the neocortex (NCx), remain in the migratory stream for days before invading the cortical plate during late corticogenesis. Here we show that in developing mouse cortices, INs in the piriform cortex (PCx; the major olfactory cortex) distribute differently from those in the NCx. We provide evidence that during development INs invade and mature earlier in PCx than in NCx, likely owing to the lack of CXCR4 expression in INs from PCx compared to those in NCx. We analyzed IN distribution patterns in Lhx2 cKO mice, where projection neurons in the lateral NCx are re-fated to generate an ectopic PCx (ePCx). The PCx-specific IN distribution patterns found in ePCx suggest that properties of PCx projection neurons regulate IN distribution. Collectively, our results show that the timing of IN invasion in the developing PCx fundamentally differs from what is known in the NCx. Further, our results suggest that projection neurons instruct the PCx-specific pattern of IN distribution.


Assuntos
Interneurônios/fisiologia , Neocórtex/embriologia , Neocórtex/crescimento & desenvolvimento , Córtex Piriforme/enzimologia , Córtex Piriforme/crescimento & desenvolvimento , Fatores Etários , Animais , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Neocórtex/citologia , Neurogênese/fisiologia , Córtex Piriforme/citologia
6.
Zhongguo Zhong Yao Za Zhi ; 46(11): 2857-2864, 2021 Jun.
Artigo em Zh | MEDLINE | ID: mdl-34296586

RESUMO

The liver and kidney fibrosis model was established by thioacetamide(TAA) and unilateral ureteral obstruction(UUO) in SD rats. The rats were randomly divided into three groups: model group, low and high-dose groups of C21 steroidal glycosides of Cynanchum auriculatum. Another blank control group was set. Four weeks later, serum was taken to detect the biochemical indexes of liver and kidney function. Urine protein and urine creatinine were detected by kits. Liver and kidney tissue samples were stained with HE and Masson staining, and hydroxyproline content was detected. Western blot was used to detect expressions of fibrotic proteins, inflammatory factors and TLR4 signaling pathways, so as to observe the preventive and therapeutic effects of C21 steroidal glycosides from C. auriculatum on hepatic and renal fibrosis and explore its molecular mechanism. Four weeks later, serum biochemical results showed that liver and kidney functions were seriously damaged, and pathological sections showed that inflammatory cell infiltration, decrease of parenchymal cells, and increase of interstitial fibrosis in liver and kidney tissues. The results showed that low and high doses(150, 300 mg·kg~(-1)) of C21 steroidal glycosides could significantly reduce the collagen deposition and the pathological changes of liver and kidney fibrosis compared with the model group. At the same time, we found that the expression levels of TLR4 and MyD88 signaling pathway proteins were significantly increased in the liver and kidney tissues of the model group, and a large number of NF-κB signaling pathway proteins migrated into the nucleus. On the contrary, the expression levels of TLR4, MyD88 signaling pathway proteins and the nuclear migration of NF-κB were significantly inhibited in the low and high dose groups of C21 steroidal glycosides from C. auriculatum. Therefore, it was speculated that the mechanism of C21 steroidal glycoside for preventive and therapeutic effect on hepatic and renal fibrosis was related to inhibit TLR4/MYD88/NF-κB inflammatory pathway, thus preventing hepatic and renal fibrosis.


Assuntos
Cynanchum , Animais , Fibrose , Glicosídeos , Rim/patologia , Fígado , NF-kappa B/genética , Ratos , Ratos Sprague-Dawley , Receptor 4 Toll-Like/genética
7.
Nat Immunol ; 9(8): 898-907, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18604210

RESUMO

The inhibitory signaling of natural killer (NK) cells is crucial in the regulation of innate immune responses. Here we show that the association of KIR2DL1, an inhibitory receptor of NK cells, with beta-arrestin 2 mediated recruitment of the tyrosine phosphatases SHP-1 and SHP-2 to KIR2DL1 and facilitated 'downstream' inhibitory signaling. Consequently, the cytotoxicity of NK cells was higher in beta-arrestin 2-deficient mice but was inhibited in beta-arrestin 2-transgenic mice. Moreover, beta-arrestin 2-deficient mice were less susceptible than wild-type mice to mouse cytomegalovirus infection, an effect that was abolished by depletion of NK cells. Our findings identify a previously unknown mechanism by which the inhibitory signaling in NK cells is regulated.


Assuntos
Arrestinas/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Receptores Imunológicos/imunologia , Transdução de Sinais/imunologia , Animais , Células Cultivadas , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Receptores Imunológicos/química , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , beta-Arrestina 2 , beta-Arrestinas
8.
J Therm Biol ; 88: 102486, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32125976

RESUMO

This study aimed to investigate genetic markers and candidate genes associated with thermotolerance in a layer-type strain Taiwan indigenous chickens exposed to acute heat stress. One hundred and ninety-two 30-week-old roosters were subjected to acute heat stress. Changes in body temperature (BT, ΔT) were calculated by measuring the difference between the initial BT and the highest BT during heat stress and the results were categorized into dead, susceptible, tolerant, and intermediate groups depending on their survival and ΔT values at the end of the experiment. A genome-wide association study on survival and ΔT values was conducted using the Cochran-Armitage trend test and Fisher's exact test. Association analyses identified 80 significant SNPs being annotated to 23 candidate genes, 440 SNPs to 71 candidate genes, 64 SNPs to 25 candidate genes, and 378 SNPs to 78 candidate genes in the dead versus survivor, tolerant versus susceptible, intermediate versus tolerant, and intermediate versus susceptible groups, respectively. The annotated genes were associated with apoptosis, cellular stress responses, DNA repair, and metabolic oxidative stress. In conclusion, the identified SNPs of candidate genes provide insights into the potential mechanisms underlying physiological responses to acute heat stress in chickens.


Assuntos
Galinhas/fisiologia , Transtornos de Estresse por Calor/genética , Doenças das Aves Domésticas/genética , Termotolerância/genética , Animais , Galinhas/genética , Genômica , Transtornos de Estresse por Calor/veterinária , Masculino , Polimorfismo de Nucleotídeo Único , Taiwan
9.
Anim Biotechnol ; 30(1): 43-56, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29426259

RESUMO

The purpose of this study was to investigate the change in protein expression in the testes of ganders at various breeding stages. A total of nine 3-year-old male White Roman ganders were used. The blood and testis samples were collected at the nonbreeding, sexual reactivation, and breeding stages for sex hormone analysis and proteomic analysis, respectively. The testicular weight and serum testosterone observed for ganders at the breeding stage were higher than those for ganders at nonbreeding and sexual reactivation stages (P < 0.05). There were 124 protein spots differentially expressed in the testes of ganders at various reproductive stages. A total of 107 protein spots of 74 proteins was identified through mass spectrometry. Most of the differentially expressed proteins were responsible for the molecular functions of protein binding (24%) and catalytic activity (16%). A functional pathway analysis suggested that proteins involved in steroidogenesis, metabolism, and spermatogenesis pathways changed in the White Roman geese at various reproductive stages. In conclusion, ganders at various reproductive stages exhibited different levels of testosterone and protein expression in the testes. The varied levels of the proteins might be essential and unique key factors in seasonal reproduction in ganders.


Assuntos
Gansos/fisiologia , Proteoma , Reprodução , Animais , Cruzamento , Masculino , Proteômica , Estações do Ano , Testículo/fisiologia , Testosterona/metabolismo
10.
J Therm Biol ; 82: 33-42, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31128657

RESUMO

Body temperature is the simplest parameter for evaluating the physiological conditions of animals under thermal stress. Genome-wide association studies (GWAS) have identified candidate genes related to economic traits in domestic animals. The present study conducted a GWAS on body temperature changes in a broiler-type strain Taiwan country chickens (TCCs) under acute heat stress. A total of two hundred 30-week-old roosters of a broiler-type strain TCCs were used. The roosters were subjected to acute heat stress at 38 °C for 4 h, and their body temperature was recorded before and during heat stress. The change in body temperature (ΔT) of each rooster was calculated according to the difference between the initial temperature and the highest body temperature during heat stress. The roosters were categorized according to survival and ΔT at the end into dead, susceptible, resistant, and intermediate groups. Collected red blood cells were genotyped using a 600 K chicken single-nucleotide polymorphism (SNP) array. A GWAS for ΔT was conducted using the Cochran-Armitage trend test. Significant SNPs were annotated as candidate genes according to the nearest genes. Results indicated that the ΔT of the heat-resistant group was significantly lower than that of the heat-susceptible group. A total of 17 SNPs belonging to 8 candidate genes, 352 SNPs for 78 candidate genes, and 174 significant SNPs for 63 candidate genes were identified in the association analyses in the dead vs. survival, resistant vs. susceptible, and intermediate vs. susceptible groups, respectively. The annotated candidate genes are associated with apoptosis, cellular response to external stimuli, and signal transduction pathways. In conclusion, the significant SNPs located in and proximal to genes in the GWAS analysis were related to apoptosis or responses to external stimuli which serve as potential candidates underlying physiological adaptation to heat stress or thermotolerance in chickens.


Assuntos
Galinhas/genética , Estudo de Associação Genômica Ampla , Resposta ao Choque Térmico , Locos de Características Quantitativas , Animais , Proteínas Aviárias/genética , Temperatura Corporal , Galinhas/fisiologia , Perfilação da Expressão Gênica , Ontologia Genética , Polimorfismo de Nucleotídeo Único , Taiwan
11.
Prog Orthod ; 25(1): 2, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38185724

RESUMO

BACKGROUND: Orthodontic tooth movement (OTM) in a region containing alveolar bone defects with insufficient height and width is hard to achieve. Bovine bone mineral (Bio-Oss) is available to restore the alveolar defect; however, whether the region augmented with a bovine bone mineral graft (BG) is feasible for OTM, and the mechanisms by which macrophages remodel the BG material, is uncertain under the mechanical force induced by OTM. MATERIAL AND METHODS: Rats were divided into three groups: OTM (O), OTM + BG material (O + B), and Control (C). First molars were extracted to create bone defects in the O and O + B groups with bovine bone mineral grafting in the latter. Second molars received OTM towards the bone defects in both groups. After 28 days, maxillae were analyzed using microfocus-computed tomography (µCT) and scanning-electron-microscopy (SEM); and macrophages (M1/M2) were stained using immunofluorescence. THP-1 cell-induced macrophages were cultured under mechanical force (F), BG material (B), or both (F + B). Phagocytosis-related signaling molecules (cAMP/PKA/RAC1) were analyzed, and conditioned media was analyzed for MMP-9 and cytokines (IL-1ß, IL-4). RESULTS: Our study demonstrated that alveolar defects grafted with BG materials are feasible for OTM, with significantly increased OTM distance, bone volume, and trabecular thickness in this region. SEM observation revealed that the grafts served as a scaffold for cells to migrate and remodel the BG materials in the defect during OTM. Moreover, the population of M2 macrophages increased markedly both in vivo and in cell culture, with enhanced phagocytosis via the cAMP/PKA/RAC1 pathway in response to mechanical force in combination with BG particles. By contrast, M1 macrophage populations were decreased under the same circumstances. In addition, M2 macrophage polarization was also indicated by elevated IL-4 levels, reduced IL-1ß levels, and less active MMP-9 in cell culture. CONCLUSION: This study explored the mechanisms of mechanical force-induced alveolar bone remodeling with bovine bone mineral grafts during OTM. The results might provide molecular insights into the related clinical problems of whether we can move teeth into the grafted materials; and how these materials become biologically remodeled and degraded under mechanical force.


Assuntos
Interleucina-4 , Metaloproteinase 9 da Matriz , Animais , Bovinos , Ratos , Técnicas de Movimentação Dentária , Minerais
12.
Neurosci Bull ; 40(4): 483-499, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37979054

RESUMO

Chronic cerebral hypoperfusion is one of the pathophysiological mechanisms contributing to cognitive decline by causing white matter injury. Microglia phagocytosing myelin debris in a timely manner can promote remyelination and contribute to the repair of white matter. However, milk fat globule-epidermal growth factor-factor 8 (MFG-E8), a microglial phagocytosis-related protein, has not been well studied in hypoperfusion-related cognitive dysfunction. We found that the expression of MFG-E8 was significantly decreased in the brain of mice after bilateral carotid artery stenosis (BCAS). MFG-E8 knockout mice demonstrated more severe BCAS-induced cognitive impairments in the behavioral tests. In addition, we discovered that the deletion of MFG-E8 aggravated white matter damage and the destruction of myelin microstructure through fluorescent staining and electron microscopy. Meanwhile, MFG-E8 overexpression by AAV improved white matter injury and increased the number of mature oligodendrocytes after BCAS. Moreover, in vitro and in vivo experiments showed that MFG-E8 could enhance the phagocytic function of microglia via the αVß3/αVß5/Rac1 pathway and IGF-1 production to promote the differentiation of oligodendrocyte progenitor cells into mature oligodendrocytes. Interestingly, we found that MFG-E8 was mainly derived from astrocytes, not microglia. Our findings suggest that MFG-E8 is a potential therapeutic target for cognitive impairments following cerebral hypoperfusion.


Assuntos
Isquemia Encefálica , Disfunção Cognitiva , Remielinização , Camundongos , Animais , Bainha de Mielina , Fagocitose/fisiologia , Microglia/metabolismo , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Isquemia Encefálica/complicações , Isquemia Encefálica/metabolismo , Camundongos Knockout , Camundongos Endogâmicos C57BL
13.
Heliyon ; 10(4): e25616, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38375275

RESUMO

Pigs are natural host to various zoonotic pathogens including viruses. In this study, we analyzed the viral communities in the feces of 89 piglets with diarrhea under one month old which were collected from six farms in Jiangsu Province of the Eastern China, using the unbiased virus metagenomic method. A total of 89 libraries were constructed, and 46937894 unique sequence reads were generated by Illumina sequencing. Overall, the family Picornaviridae accounted for the majority of the total reads of putative mammalian viruses. Ten novel virus genomes from different family members were discovered, including Parvoviridae (n = 2), Picobirnaviridae (n = 4) and CRESS DNA viruses (n = 4). A large number of phages were identified, which mainly belonged to the order Caudovirales and the family Microviridae. Moreover, some identified viruses were closely related to viruses found in non-porcine hosts, highlighting the potential for cross-species virus dissemination. This study increased our understanding of the fecal virus communities of diarrhea piglets and provided valuable information for virus monitoring and preventing.

14.
PLoS One ; 19(4): e0301702, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38573944

RESUMO

BACKGROUND: ChatGPT is a large language model designed to generate responses based on a contextual understanding of user queries and requests. This study utilised the entrance examination for the Master of Clinical Medicine in Traditional Chinese Medicine to assesses the reliability and practicality of ChatGPT within the domain of medical education. METHODS: We selected 330 single and multiple-choice questions from the 2021 and 2022 Chinese Master of Clinical Medicine comprehensive examinations, which did not include any images or tables. To ensure the test's accuracy and authenticity, we preserved the original format of the query and alternative test texts, without any modifications or explanations. RESULTS: Both ChatGPT3.5 and GPT-4 attained average scores surpassing the admission threshold. Noteworthy is that ChatGPT achieved the highest score in the Medical Humanities section, boasting a correct rate of 93.75%. However, it is worth noting that ChatGPT3.5 exhibited the lowest accuracy percentage of 37.5% in the Pathology division, while GPT-4 also displayed a relatively lower correctness percentage of 60.23% in the Biochemistry section. An analysis of sub-questions revealed that ChatGPT demonstrates superior performance in handling single-choice questions but performs poorly in multiple-choice questions. CONCLUSION: ChatGPT exhibits a degree of medical knowledge and the capacity to aid in diagnosing and treating diseases. Nevertheless, enhancements are warranted to address its accuracy and reliability limitations. Imperatively, rigorous evaluation and oversight must accompany its utilization, accompanied by proactive measures to surmount prevailing constraints.


Assuntos
Inteligência Artificial , Medicina Clínica , Avaliação Educacional , Idioma , Reprodutibilidade dos Testes
15.
ACS Appl Mater Interfaces ; 15(38): 44742-44751, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37721982

RESUMO

Exploring new ways to reconstruct the structure and function of inappropriate organic fluorophores for improving amyloid-ß (Aß) fluorescent imaging performance is desired for precise detection and early diagnosis of Alzheimer's disease (AD). With stilbazolium dyes as examples, here, we present a multipronged approach to comprehensively improved the Aß fluorescent imaging performance through a flexible bivalent method, where a flexible carbon chain was introduced to link two monomers to form a homodimer. Our results reveal a mechanism wherein the flexible linker creates a well-defined probe with specific orientations and distinct photophysical properties. Applying this approach in combination with theoretical simulation, the homodimers exhibited a comprehensive improvement of the Aß fluorescent imaging performance of the dye monomers, including better photostability and higher signal-to-noise (S/N) ratio, higher "off-on" near-infrared fluorescence (NIRF) response sensitivity, higher specificity and affinity to Aß deposits, and more reasonable lipophilicity for blood-brain barrier (BBB) penetrability. The results demonstrate that flexible homodimers offer a multipronged approach to obtaining high-performance NIRF imaging reagents for the detection of Aß deposits both in vitro and in vivo.


Assuntos
Doença de Alzheimer , Corantes Fluorescentes , Humanos , Peptídeos beta-Amiloides , Doença de Alzheimer/diagnóstico por imagem , Barreira Hematoencefálica , Carbono
16.
Microbiol Spectr ; 11(3): e0472722, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37166308

RESUMO

During a 2020 routine epidemiological investigation of carbapenem-resistant Enterobacterales at a local food market in Guangzhou, China, two Escherichia coli ST410 isolates coproducing NDM-5 and OXA-181 were obtained from environmental samples. Antimicrobial susceptibility testing, whole-genome sequencing, and conjugation assays were applied to identify their resistance phenotypes, phylogenetic relatedness, and genetic characteristics. Phylogenetic analysis showed that the two isolates were clonally related with only one core-genome single-nucleotide polymorphism (SNP) difference and clustered into a branch with 87 E. coli ST410 isolates deposited in GenBank. These 89 ST410 isolates were closely related (≤51 SNPs), and most were from humans in Southeast Asian countries (n = 47). A Vietnamese clinical isolate collected in 2017 showed the strongest epidemiological link (seven SNPs) to the two ST410 isolates detected in this study. Complete-genome analysis revealed that the carbapenem resistance determinants blaNDM-5 and blaOXA-181 were located on an IncF1:A1:B49-IncQ1 plasmid and IncX3 plasmid, respectively. Conjugation experiments confirmed that the IncX3 plasmid was self-transmissible while the IncF1:A1:B49-IncQ1 plasmid was nonconjugative. BLASTn analysis indicated that the two plasmids showed high similarity to other blaNDM-5-bearing IncF1:A1:B49-IncQ1 and blaOXA-181-bearing IncX3 plasmids from other countries. Altogether, the high similarity of the core genomes and plasmids between the ST410 isolates found in this study and those human source isolates from foreign countries suggested the clonal spread of E. coli ST410 strains and horizontal transmission of blaOXA-181-bearing IncX3 plasmids across Southeast Asian countries. Stringent sanitary management of food markets is important to prevent the dissemination of high-risk clones to the public. IMPORTANCE This is the first report of an Escherichia coli ST410 clone that coproduces NDM-5 and OXA-181 in China. The high similarity of the core genomes and plasmids between the ST410 isolates characterized in this study and human source isolates from foreign countries strongly suggests that this ST410 lineage is an international high-risk clone, highlighting the need for continuous global surveillance of ST410 clones.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Humanos , Infecções por Escherichia coli/epidemiologia , Filogenia , beta-Lactamases/genética , Carbapenêmicos/farmacologia , Plasmídeos/genética , China/epidemiologia , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia
17.
Chin J Dent Res ; 26(3): 153-162, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37732681

RESUMO

OBJECTIVE: To explore the high-efficiency and low-risk prevention and treatment strategies for stem cells from human exfoliated deciduous teeth (SHED) for high-altitude cerebral oedema. METHODS: A low-pressure and low-oxygen tank mimicking high-altitude conditions was used to establish the high-altitude cerebral oedema animal model. The preventive effects of SHED for cerebral oedema were then evaluated by haematoxylin and eosin (H&E) and histological staining. In vitro, SHED was co-cultured with BV-2 to analyse the effects of SHED by western blot and immunofluorescence staining. RESULTS: SHED can prevent and treat cerebral oedema in a high altitude rat animal model. Mechanistically, SHED treatment can protect brain cells from apoptosis induced by high altitude condition. Moreover, SHED treatment can inhibit M1-type polarisation and promote M2-type polarisation of microglia cells via the suppression of hypoxia inducible factor (HIF)- 1α-mediated extracellular signal-regulated kinase (ERK) signalling activated in high altitude condition. CONCLUSION: SHED treatment can relieve high-altitude cerebral oedema via inhibiting HIF- 1α-mediated ERK signalling, which indicates that SHED is a promising alternative strategy to prevent and treat high-altitude cerebral oedema.


Assuntos
Doença da Altitude , Edema Encefálico , Humanos , Animais , Ratos , Edema Encefálico/etiologia , Edema Encefálico/terapia , Microglia , Altitude , Células-Tronco , MAP Quinases Reguladas por Sinal Extracelular , Dente Decíduo
18.
Heliyon ; 9(6): e17222, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37389044

RESUMO

Viral diseases caused by new outbreaks of viral infections pose a serious threat to human health. Wild brown rats (Rattus norvegicus), considered one of the world's largest and most widely distributed rodents, are host to various zoonotic pathogens. To further understand the composition of the virus community in wild brown rats and explore new types of potentially pathogenic viruses, viral metagenomics was conducted to investigate blood, feces, and various tissues of wild brown rats captured from Zhenjiang, China. Results indicated that the composition of the virus community in different samples showed significant differences. In blood and tissue samples, members of the Parvoviridae and Anelloviridae form the main body of the virus community. Picornaviridae, Picobirnaviridae, and Astroviridae made up a large proportion of fecal samples. Several novel genome sequences from members of different families, including Anelloviridae, Parvoviridae, and CRESS DNA viruses, were detected in both blood and other samples, suggesting that they have the potential to spread across organs to cause viremia. These viruses included not only strains closely related to human viruses, but also a potential recombinant virus. Multiple dual-segment picornaviruses were obtained from fecal samples, as well as virus sequences from the Astroviridae and Picornaviridae. Phylogenetic analysis showed that these viruses belonged to different genera, with multiple viruses clustered with other animal viruses. Whether they have pathogenicity and the ability to spread across species needs further study.

19.
Hum Cell ; 35(3): 896-908, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35174471

RESUMO

Ovarian cancer is one of the most lethal gynecologic malignancies worldwide, with the 5-year survival is less than 50%. Although some clinical achievements have been achieved, the overall survival rate has remained unchanged over the past 20 years. Therefore, it is necessary and urgent to develop the potential modifiers and therapeutic approach to improve the overall survival rate in ovarian cancer patients. RBCK1 is an RING protein E3 ubiquitin ligase, which was revealed to involve in the progression of several cancers through its ubiquitination function. In this research, we report that RBCK1 expression is significantly elevated in human ovarian cancer and strongly associated with poor patients' prognosis. RBCK1 deficiency induces cell apoptosis and inhibits cell proliferation and migration in ovarian cancer cells. In terms of molecular mechanism, we report that RBCK1 interacts with PTEN and promotes PTEN degradation in K48-linked ubiquitination. Our study suggests a new and interesting regulatory mechanism that RBCK1 facilitates PTEN degradation, which could be a new potential therapeutic target for ovarian cancer treatment.


Assuntos
Neoplasias Ovarianas , Ubiquitina-Proteína Ligases , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/terapia , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
20.
Front Vet Sci ; 9: 878441, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35782540

RESUMO

Since 2014, a goose-origin astroviruses disease, which is characterized by urate precipitation in viscera, has rapidly spread to major commercial goose provinces leading to huge economic losses in the poultry industry of China. In March 2020, a goose farm locates in Shanghai, China, where there was no goose astroviruses (GAstVs) infection reported before, experienced an outbreak of gout disease in geese. The etiological investigation was carried out by virus metagenomics and bacterial culture and two GAstVs strains, designated as CHSH01 and CHSH02, were determined. Their complete genomes were measured to 7,154 and 7,330 nt in length, excludingthe poly(A) tail, respectively, and had different genomic features and classifications. CHSH01 shared a very low sequence identity with other strains in terms of not only the complete genome but also different ORFs. Phylogenetic analysis showed CHSH02 belonged to GAstV-2, which was the predominant species in the geese with gout in China according to the previous study. Meanwhile, CHSH01 strain displayed low identity with other AstVs, and phylogenetic and recombination analysis suggested that CHSH01 belonging to a novel type was a recombinant strain, one parent strain of which was an AstV determined from a bar-headed goose (a kind of migrant bird). Moreover, the primary epidemiological investigation showed that the two strains were prevalent in the same goose farm and co-infection occurred. These findings arise the potential cross-species transmission of CHSH01 between domestic and wild fowl.

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