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1.
Nano Lett ; 24(28): 8732-8740, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38958407

RESUMO

Piwi-interacting RNAs (piRNAs) are small noncoding RNAs that repress transposable elements to maintain genome integrity. The canonical catalytic hairpin assembly (CHA) circuit relies on random collisions of free-diffused reactant probes, which substantially slow down reaction efficiency and kinetics. Herein, we demonstrate the construction of a spatial-confined self-stacking catalytic circuit for rapid and sensitive imaging of piRNA in living cells based on intramolecular and intermolecular hybridization-accelerated CHA. We rationally design a 3WJ probe that not only accelerates the reaction kinetics by increasing the local concentration of reactant probes but also eliminates background signal leakage caused by cross-entanglement of preassembled probes. This strategy achieves high sensitivity and good specificity with shortened assay time. It can quantify intracellular piRNA expression at a single-cell level, discriminate piRNA expression in tissues of breast cancer patients and healthy persons, and in situ image piRNA in living cells, offering a new approach for early diagnosis and postoperative monitoring.


Assuntos
RNA Interferente Pequeno , Humanos , RNA Interferente Pequeno/genética , Catálise , Hibridização de Ácido Nucleico , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/metabolismo , Cinética , RNA de Interação com Piwi
2.
J Antimicrob Chemother ; 79(1): 100-111, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37962091

RESUMO

OBJECTIVES: Our study aimed to sequence class 1 integrons in uncultured environmental bacterial cells in freshwater from suburban creeks and uncover the taxonomy of their bacterial hosts. We also aimed to characterize integron gene cassettes with altered DNA sequences relative to those from databases or literature and identify key signatures of their molecular evolution. METHODS: We applied a single-cell fusion PCR-based technique-emulsion, paired isolation and concatenation PCR (epicPCR)-to link class 1 integron gene cassette arrays to the phylogenetic markers of their bacterial hosts. The levels of streptomycin resistance conferred by the WT and altered aadA5 and aadA11 gene cassettes that encode aminoglycoside (3″) adenylyltransferases were experimentally quantified in an Escherichia coli host. RESULTS: Class 1 integron gene cassette arrays were detected in Alphaproteobacteria and Gammaproteobacteria hosts. A subset of three gene cassettes displayed signatures of molecular evolution, namely the gain of a regulatory 5'-untranslated region (5'-UTR), the loss of attC recombination sites between adjacent gene cassettes, and the invasion of a 5'-UTR by an IS element. Notably, our experimental testing of a novel variant of the aadA11 gene cassette demonstrated that gaining the observed 5'-UTR contributed to a 3-fold increase in the MIC of streptomycin relative to the ancestral reference gene cassette in E. coli. CONCLUSIONS: Dissecting the observed signatures of molecular evolution of class 1 integrons allowed us to explain their effects on antibiotic resistance phenotypes, while identifying their bacterial hosts enabled us to make better inferences on the likely origins of novel gene cassettes and IS that invade known gene cassettes.


Assuntos
Escherichia coli , Integrons , Integrons/genética , Filogenia , Emulsões , Antibacterianos/farmacologia , Reação em Cadeia da Polimerase , Bactérias , Estreptomicina , Evolução Molecular , Farmacorresistência Bacteriana/genética
3.
J Med Virol ; 95(12): e29300, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38063070

RESUMO

Little is known about antibody responses to natural Omicron infection and the risk factors for poor responders in patients with hematological malignancies (HM). We conducted a multicenter, prospective cohort study during the latest Omicron wave in Chongqing, China, aiming to compare the antibody responses, as assessed by IgG levels of anti-receptor binding domain of spike protein (anti-S-RBD), to Omicron infection in the HM cohort (HMC) with healthy control cohort (HCC), and solid cancer cohort (SCC). In addition, we intend to explore the risk factors for poor responders in the HMC. Among the 466 HM patients in this cohort, the seroconversion rate was 92.7%, no statistically difference compared with HCC (98.2%, p = 0.0513) or SCC (100%, p = 0.1363). The median anti-S-RBD IgG titer was 29.9 ng/mL, significantly lower than that of HCC (46.9 ng/mL, p < 0.0001) or SCC (46.2 ng/mL, p < 0.0001). Risk factors associated with nonseroconversion included no COVID-19 vaccination history (odds ratio [OR] = 4.58, 95% confidence interval [CI]: 1.75-12.00, p = 0.002), clinical course of COVID-19 ≤ 7 days (OR = 2.86, 95% CI: 1.31-6.25, p = 0.008) and severe B-cell reduction (0-10/µL) (OR = 3.22, 95% CI: 1.32-7.88, p = 0.010). Risk factors associated with low anti-S-RBD IgG titer were clinical course of COVID-19 ≤ 7 days (OR = 2.58, 95% CI: 1.59-4.18, p < 0.001) and severe B-cell reduction (0-10/µL) (OR = 2.87, 95% CI: 1.57-5.24, p < 0.001). This study reveals a poor antibody responses to Omicron (BA.5.2.48) infection in HM patients and identified risk factors for poor responders. Highlights that HM patients, especially those with these risk factors, may be susceptible to SARS-CoV-2 reinfection, and the postinfection vaccination strategies for these patients should be tailored. Clinical trial: ChiCTR2300071830.


Assuntos
COVID-19 , Neoplasias Hematológicas , Humanos , Formação de Anticorpos , SARS-CoV-2 , Estudos Prospectivos , Neoplasias Hematológicas/complicações , Progressão da Doença , Imunoglobulina G , Anticorpos Antivirais
4.
Neurochem Res ; 48(8): 2406-2423, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36976393

RESUMO

The available data on the localization of transforming growth factor beta1 (TGF-ß1), glial cell line-derived neurotrophic factor (GDNF), and platelet-derived growth factor-BB (PDGF-BB) in the adult primate and human central nervous system (CNS) are limited and lack comprehensive and systematic information. This study aimed to investigate the cellular localization and distribution of TGF-ß1, GDNF, and PDGF-BB in the CNS of adult rhesus macaque (Macaca mulatta). Seven adult rhesus macaques were included in the study. The protein levels of TGF-ß1, PDGF-BB, and GDNF in the cerebral cortex, cerebellum, hippocampus, and spinal cord were analyzed by western blotting. The expression and location of TGF-ß1, PDGF-BB, and GDNF in the brain and spinal cord was examined by immunohistochemistry and immunofluorescence staining, respectively. The mRNA expression of TGF-ß1, PDGF-BB, and GDNF was detected by in situ hybridization. The molecular weight of TGF-ß1, PDGF-BB, and GDNF in the homogenate of spinal cord was 25 KDa, 30 KDa, and 34 KDa, respectively. Immunolabeling revealed GDNF was ubiquitously distributed in the cerebral cortex, hippocampal formation, basal nuclei, thalamus, hypothalamus, brainstem, cerebellum, and spinal cord. TGF-ß1 was least distributed and found only in the medulla oblongata and spinal cord, and PDGF-BB expression was also limited and present only in the brainstem and spinal cord. Besides, TGF-ß1, PDGF-BB, and GDNF were localized in the astrocytes and microglia of spinal cord and hippocampus, and their expression was mainly found in the cytoplasm and primary dendrites. The mRNA of TGF-ß1, PDGF-BB, and GDNF was localized to neuronal subpopulations in the spinal cord and cerebellum. These findings suggest that TGF-ß1, GDNF and PDGF-BB may be associated with neuronal survival, neural regeneration and functional recovery in the CNS of adult rhesus macaques, providing the potential insights into the development or refinement of therapies based on these factors.


Assuntos
Fator Neurotrófico Derivado de Linhagem de Célula Glial , Fator de Crescimento Transformador beta1 , Animais , Becaplermina , Macaca mulatta/metabolismo , RNA Mensageiro , Medula Espinal/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
5.
Environ Sci Technol ; 57(12): 4870-4879, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36912846

RESUMO

Horizontal gene transfer (HGT) is a key driver of bacterial evolution via transmission of genetic materials across taxa. Class 1 integrons are genetic elements that correlate strongly with anthropogenic pollution and contribute to the spread of antimicrobial resistance (AMR) genes via HGT. Despite their significance to human health, there is a shortage of robust, culture-free surveillance technologies for identifying uncultivated environmental taxa that harbor class 1 integrons. We developed a modified version of epicPCR (emulsion, paired isolation, and concatenation polymerase chain reaction (PCR)) that links class 1 integrons amplified from single bacterial cells to taxonomic markers from the same cells in emulsified aqueous droplets. Using this single-cell genomic approach and Nanopore sequencing, we successfully assigned class 1 integron gene cassette arrays containing mostly AMR genes to their hosts in coastal water samples that were affected by pollution. Our work presents the first application of epicPCR for targeting variable, multigene loci of interest. We also identified the Rhizobacter genus as novel hosts of class 1 integrons. These findings establish epicPCR as a powerful tool for linking taxa to class 1 integrons in environmental bacterial communities and offer the potential to direct mitigation efforts toward hotspots of class 1 integron-mediated dissemination of AMR.


Assuntos
Farmacorresistência Bacteriana , Integrons , Humanos , Integrons/genética , Farmacorresistência Bacteriana/genética , Fusão Celular , Bactérias/genética , Reação em Cadeia da Polimerase , Antibacterianos/farmacologia
6.
BMC Med Imaging ; 23(1): 26, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36747143

RESUMO

PURPOSE: To verify whether radiomics techniques based on dual-modality ultrasound consisting of B-mode and superb microvascular imaging (SMI) can improve the accuracy of the differentiation between gallbladder neoplastic polyps and cholesterol polyps. METHODS: A total of 100 patients with 100 pathologically proven gallbladder polypoid lesions were enrolled in this retrospective study. Radiomics features on B-mode ultrasound and SMI of each lesion were extracted. Support vector machine was used to classify adenomas and cholesterol polyps of gallbladder for B-mode, SMI and dual-modality ultrasound, respectively, and the classification results were compared among the three groups. RESULTS: Six, eight and nine features were extracted for each lesion at B-mode ultrasound, SMI and dual-modality ultrasound, respectively. In dual-modality ultrasound model, the area under the receiver operating characteristic curve (AUC), classification accuracy, sensitivity, specificity, and Youden's index were 0.850 ± 0.090, 0.828 ± 0.097, 0.892 ± 0.144, 0.803 ± 0.149 and 0.695 ± 0.157, respectively. The AUC and Youden's index of the dual-modality model were higher than those of the B-mode model (p < 0.05). The AUC, accuracy, specificity and Youden's index of the dual-modality model were higher than those of the SMI model (p < 0.05). CONCLUSIONS: Radiomics analysis of the dual-modality ultrasound composed of B-mode and SMI can improve the accuracy of classification between gallbladder neoplastic polyps and cholesterol polyps.


Assuntos
Vesícula Biliar , Pólipos , Humanos , Projetos Piloto , Vesícula Biliar/diagnóstico por imagem , Vesícula Biliar/patologia , Diagnóstico Diferencial , Estudos Retrospectivos , Ultrassonografia/métodos , Pólipos/diagnóstico por imagem , Pólipos/patologia , Colesterol
7.
Int Wound J ; 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853846

RESUMO

We conducted a meta-analysis to assess the effects of bundle-care interventions on pressure ulcers in patients with stroke to provide a basis for clinical work. Randomised controlled trials on the effects of bundle-care interventions in patients with stroke were identified using computerised searches of the PubMed, Embase, Cochrane Library, Chinese National Knowledge Infrastructure, VIP and Wanfang databases, from the time of inception of each database to July 2023, supplemented by manual literature searches. Two researchers independently retrieved and screened the articles, extracted the data and evaluated the quality of the included studies. After reaching consensus, meta-analysis was performed using RevMan 5.4. Twenty-four papers were included, involving 3330 patients of whom 1679 were in the intervention group and 1651 were in the control group. The results showed that, compared with standard care, bundle-care interventions significantly reduced the incidence of pressure ulcers (3.28% vs. 14.84%, odds ratio [OR]: 0.19, 95% confidence interval [CI]: 0.14-0.26, p < 0.001), and aspiration (5.60% vs. 18.84%, OR: 0.25, 95% CI: 0.17-0.39, p < 0.001), and improved patient satisfaction with nursing care (96.59% vs. 84.43%, OR. 5.45, 95% CI: 3.76-7.90, p < 0.001). Current evidence suggests that care bundles are significantly better than conventional nursing measures in preventing pressure ulcers and aspiration, and improving patient satisfaction with nursing care in patients with stroke, and are worthy of clinical promotion and application.

8.
BMC Gastroenterol ; 22(1): 62, 2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35151255

RESUMO

BACKGROUND: The pathogenesis of ulcerative colitis (UC) is closely related to the gut microbiota. Moxibustion has been used to improve the inflammation and gastrointestinal dysfunctions in gastrointestinal disorders such as UC. In this study, we investigated whether moxibustion could improve the gut microbial dysbiosis induced by dextran sulphate sodium. METHODS: Twenty-five male rats were randomly assigned into five groups. The UC rat model was established by administering DSS solution. The rats in the moxibustion and normal rats with moxibustion groups were treated with moxibustion at Tianshu (bilateral, ST25) points, and the mesalazine group rats were treated with mesalazine once daily for 7 consecutive days. Disease activity index (DAI) and haematoxylin and eosin staining were used to evaluate the effect of moxibustion. Gut microbiota profiling was conducted by metagenomic high throughput sequencing technology. The gut microbiota composition, diversity and function were analyzed and compared using metagenomics methodologies. RESULTS: The DAI scores and histopathology scores in the moxibustion and mesalazine groups were significantly decreased compared with the UC group (P < 0.01). Moxibustion treatment increased abundance levels of Bacteroidetes, Actinobacteria, Ascomycota, Synergistetes and decreased abundance of Firmicutes, Proteobacteria. At the genus level, the abundance of Bacteroides, Bacteroides_bacterium_M7, Prevotella, Bacteroidales_bacterium_H2, were increased and Bacteroides_bacterium_H3, Parabacteroides, Porphyromonas, Alistipes, Parasutterella were decreased in the UC group in comparsion with those in the NG group. Moxibustion increased the abundance of Bacteroides and Bacteroides_bacterium_H3 and decreased Bacteroides_bacterium_M7, Prevotella, Bacteroidales_bacterium_H2. In UC group, the specie Bacteroides_massiliensis was negatively (P < 0.05) correlated with IL-23, Bacteroides_eggerthii_CAG109 and Bacteroides_eggerthii were negatively (P < 0.05) correlated with TGF-ß. And the species Prevotella_sp_CAG1031 and Bacteroides_bacterium_H2 were significant positively (P < 0.05) correlated with IL-23. In addition, compare with the normal group, genes involved in certain metabolic pathways, such as energy production and conversion, amino acid transport and metabolism, carbohydrate transport and metabolism, were under-represented in the UC group, and these changes in the metabolic pathways could be reversed by moxibustion treatment and mesalazine treatment. CONCLUSIONS: Our findings suggest that moxibustion treatment may protect the host from mucosal inflammation by modulating the intestinal microbiota community.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Moxibustão , Pontos de Acupuntura , Animais , Colite/induzido quimicamente , Colite/terapia , Colite Ulcerativa/terapia , Sulfato de Dextrana , Modelos Animais de Doenças , Masculino , Ratos
9.
PLoS Pathog ; 15(3): e1007218, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30875398

RESUMO

As human population density and antibiotic exposure increase, specialised bacterial subtypes have begun to emerge. Arising among species that are common commensals and infrequent pathogens, antibiotic-resistant 'high-risk clones' have evolved to better survive in the modern human. Here, we show that the major matrix porin (OmpK35) of Klebsiella pneumoniae is not required in the mammalian host for colonisation, pathogenesis, nor for antibiotic resistance, and that it is commonly absent in pathogenic isolates. This is found in association with, but apparently independent of, a highly specific change in the co-regulated partner porin, the osmoporin (OmpK36), which provides enhanced antibiotic resistance without significant loss of fitness in the mammalian host. These features are common in well-described 'high-risk clones' of K. pneumoniae, as well as in unrelated members of this species and similar adaptations are found in other members of the Enterobacteriaceae that share this lifestyle. Available sequence data indicate evolutionary convergence, with implications for the spread of lethal antibiotic-resistant pathogens in humans.


Assuntos
Proteínas de Bactérias/fisiologia , Farmacorresistência Bacteriana/genética , Porinas/fisiologia , Resistência beta-Lactâmica/genética , Antibacterianos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana/fisiologia , Resistência Microbiana a Medicamentos , Humanos , Infecções por Klebsiella/genética , Infecções por Klebsiella/metabolismo , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidade , Testes de Sensibilidade Microbiana , Porinas/genética , Porinas/metabolismo , Virulência , Resistência beta-Lactâmica/fisiologia , beta-Lactamases/farmacologia
10.
Blood ; 133(12): 1371-1377, 2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-30642918

RESUMO

Blood type O is associated with a lower risk of myocardial infarction. Platelets play a critical role in myocardial infarction. It is not known whether the expression of blood group antigens on platelet proteins alters platelet function; we hypothesized that platelet function would be different between donors with blood type O and those with non-O. To address this hypothesis, we perfused blood from healthy type O donors (n = 33) or non-O donors (n = 54) over pooled plasma derived von Willebrand factor (VWF) protein and purified blood type-specific VWF at arterial shear and measured platelet translocation dynamics. We demonstrate for the first time that type O platelets travel farther at greater speeds before forming stable bonds with VWF. To further characterize these findings, we used a novel analytical model of platelet interaction. Modeling revealed that the kinetics for GPIb/VWF binding rate are significantly lower for type O compared with non-O platelets. Our results demonstrate that platelets from type O donors interact less with VWF at arterial shear than non-O platelets. Our results suggest a potential mechanism for the reduced risk of myocardial infarction associated with blood type O.


Assuntos
Antígenos de Grupos Sanguíneos/fisiologia , Plaquetas/fisiologia , Adesividade Plaquetária , Agregação Plaquetária , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Fator de von Willebrand/metabolismo , Feminino , Seguimentos , Humanos , Cinética , Masculino , Ligação Proteica
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(2): 138-142, 2021 Feb.
Artigo em Zh | MEDLINE | ID: mdl-33627207

RESUMO

OBJECTIVE: To study the effect of pertussis vaccination on the clinical manifestations of infants and young children with pertussis. METHODS: A retrospective analysis was performed to investigate the differences in clinical manifestations and peripheral blood cell levels between pertussis children with different pertussis vaccination status. RESULTS: A total of 1 083 children with pertussisat at age of < 3 years were enrolled, with 551 children in the unvaccinated group and 532 in the vaccinated group. Of all the children, 392 had an age of onset of < 3 months (372 were unvaccinated and 20 were vaccinated) and 691 children had an age of onset of ≥ 3 months (179 were unvaccinated and 512 were vaccinated). Compared with the vaccinated group, the unvaccinated group had a longer length of hospital stay and a higher incidence rate of respiratory failure (P < 0.05). Among the children ≥ 3 months of age, the incidence of severe pneumonia in the unvaccinated group was higher than that in the vaccinated group (P < 0.05), and the incidence of severe pneumonia was the highest in the unvaccinated group (10.6%) and the lowest in the 4-dose vaccination group (1.2%). Among the 101 patients with severe pneumonia, 80 (79.2%) were observed in the unvaccinated group and only 21 (20.8%) in the four different doses vaccination groups. For the children with an age of onset of ≥ 3 months, the unvaccinated group had higher white blood cell count, absolute value of lymphocytes, and platelet count than the vaccinated group (P < 0.05). CONCLUSIONS: Pertussis vaccination can reduce the incidence of severe pneumonia and respiratory failure and alleviate the severity of respiratory complications in infants and young children with pertussis.


Assuntos
Pneumonia , Coqueluche , Criança , Pré-Escolar , Humanos , Incidência , Lactente , Estudos Retrospectivos , Vacinação , Coqueluche/epidemiologia , Coqueluche/prevenção & controle
12.
Phytopathology ; 110(5): 1027-1038, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31961254

RESUMO

Berberine, a botanical drug, has great ability to inhibit the growth of Xanthomonas oryzae pv. oryzae. However, the antibacterial mechanism of berberine against X. oryzae pv. oryzae remains poorly understood. In this study, we investigated the physiological and transcriptional response of X. oryzae pv. oryzae to berberine. When strain X. oryzae pv. oryzae GX13 was treated with berberine (10 µg/ml), the hypersensitive response in tobacco, virulence to rice, pathogen population in the rice xylem, production of extracellular polysaccharide (EPS), and activity of extracellular hydrolases decreased, but the levels of pyruvate and ATP increased. Moreover, biofilm formation was inhibited, and the cell membrane was damaged. Transcriptome sequencing analysis showed downregulated expression of gspD, gspE, and gspF, involved in the type II secretion system (T2SS); hrcC, hrcJ, hrcN, and others, involved in the type III secretion system (T3SS); gumB and gumC, associated with EPS; zapE, ftsQ, and zapA, associated with cell division; lpxH, lpxK, kdtA, and others, associated with the membrane; and pyk, pgk, and mdh, encoding pyruvate kinase, phosphoglycerate kinase, and malate dehydrogenase, respectively. Upregulated expression was observed for nuoA, nuoB, and nuoH, encoding the NADH dehydrogenase complex, and atpF, atpC, and atpB, encoding ATP synthase. An adenylate cyclase (CyaA) fusion assay showed that berberine affects type three effector protein secretion via the T3SS and reduces effector translocation in X. oryzae pv. oryzae. It is speculated that the negative growth and virulence phenotypes of berberine-treated X. oryzae pv. oryzae GX13 may involve differentially expressed genes associated with cytoarchitecture and energy metabolism, and these effects on primary cell function may further dampen virulence and result in differential expression of T3SS- and T2SS-related genes.


Assuntos
Berberina , Oryza , Xanthomonas , Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Doenças das Plantas
13.
Plant Dis ; 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32910727

RESUMO

Crassocephalum crepidioides (Benth.) S. Moore, native to tropical Africa, is an important invasive weed in many countries, seriously threatening the safety of agricultural ecosystem. During December 2018, 100% of C. crepidioides plants exhibited leaf spots in the Kudzu (Pueraria lobata) garden in Tianlin County, Baise City, Guangxi, China (24°40'20.42″N, 106°11'33.51″E), but Kudzu was not affected by this disease. The leaf spots appeared as small brown spots surrounded by a yellow-green halo initially, enlarged to subrotund or irregular in shape, slightly sunken, then developed as a dark brown to dark spot with grey-white necrotic center (Supplementary Fig. 1 a,b), and exuded an orange droplet under high humidity conditions (Supplementary Fig. 1 c). Symptomatic leaf tissues were cut into small pieces (5 x 5 mm) from the junction of necrotic and healthy tissues, and small pieces were disinfected in 75% ethanol solution for 30 s and 0.1% mercury dichloride for 30 sec, then rinsed with sterile water 3 times. These tissues were plated onto potato dextrose agar (PDA) medium and incubated in a thermostatic incubator at 28°C under natural sunlight conditions. Four isolates with similar morphological features were obtained after purification. Colonies of these isolates exhibited creme-orange margins and aerial mycelium was sparse. The colonies formed concentric circles on the surface that were fusco-black, violet-slate and vinaceus-grey (from centre to edge), fusco-black on the reverse after 7 days (Supplementary Fig. 2 a,b), and then the pycnidia and conidia produced for about 30 days (Supplementary Fig. 2 c). Pycnidia of representative isolate YTH-12 were black, subglobose, and unilocular, 95.60-168.27 µm (average 128.32 µm) (n = 40) in diameter. The ostiole was single and central, slightly papillate to papillate and occasionally rostrate (Supplementary Fig. 2 d). Conidia were hyaline, oval to elliptical, aseptate, 2.30 to 5.83 × 1.42 to 3.50 µm (average, 4.36 × 2.03 µm) (n = 50) (Supplementary Fig. 2 e). These morphological characters are consistent with those described for Stagonosporopsis vannaccii (Crous et al. 2019). To further identify the isolate YTH-12, the rDNA internal transcribed spacer (ITS) region, 28s large subunit ribosomal RNA (LSU), RNA polymerase II second largest subunit (RPB2) gene and ß-tubulin (TUB2) gene were amplified by polymerase chain reaction using the primer pairs ITS1/ITS4 (White et al. 1990), LR0R (Rehner and Samuels 1994)/LR7 (Vilgalys and Hester 1990), Btub2Fd/Btub4Rd (Woudenberg et al. 2009) and RPB2-5F2 (Sung et al. 2007)/fRPB2-7cR (Liu et al. 1999), respectively. The PCR products were purified and sequenced by Sangon Biotech Co. Ltd. (Shanghai, China). The sequences were deposited in GenBank (accession nos. MN892355, MN893911, MN905510 and MN905511). The ITS (522 bp), LSU (1313 bp), TUB2 (380 bp) and RPB2 (1193 bp) nucleotide sequences showed 100% identity to S. vannaccii strain LFNO148 (accession nos. MK519453, MK519452, MK519454 and MN534891). Phylogenetic analysis based on the multi-locus sequences of ITS, LSU, RPB2 and TUB2 was performed in MEGA version 6.0 (Chen et al. 2015). The relative stability of the branches was evaluated by bootstrapping with 1000 replications. The isolate YTH-12 was placed in the same clade as S. vannaccii with 100% bootstrap support. Based on morphology and molecular analyses, this pathogen was identified as S. vannaccii. To satisfy Koch's postulates, the isolate YTH-12 was inoculated on leaves of C. crepidioides plants. Twenty punctured leaves and twenty unwounded leaves were inoculated with a 5-mm-diameter mycelial disc, respectively. Leaves inoculated with sterile PDA discs were used as blank controls. Plants were maintained in a growth chamber (25°C-28°C and relative humidity 80%-90%). Brown spots were observed on inoculated leaves (both punctured and unwounded) about 30 hours after inoculation and typical symptoms appeared about 55 hours after inoculation (Supplementary Fig. 1 d), and the diseased leaves produced black pycnidia and orange droplet 10 days after inoculation (Supplementary Fig. 1 e). All inoculated leaves developed symptoms similar to those on the naturally infected plants in the garden and the disease incidence reached 100%, whereas the control leaves remained symptomless (Supplementary Fig. 1 f). The same fungus was re-isolated from inoculated leaves. To our knowledge, this is the first report of S. vannaccii causing leaf spot on C. crepidioides in China. So far, Stagonosporopsis vannaccii has been reported as a plant pathogenic fungus only in Brazil, causing anthracnose symptoms on pods of soybean (Crous et al. 2019). Crassocephalum crepidioides is a widely distributed weed. If S. vannaccii has strong host specificity, it is possible to be used as a biocontrol fungus to control the weed. Conversely, if the fungus has a wider host range, C. crepidioides may act as a good bridge to spread the pathogen. This study helps to deepen the understanding of S. vannaccii and its associated plant diseases.

14.
Zhongguo Zhong Yao Za Zhi ; 45(3): 602-608, 2020 Feb.
Artigo em Zh | MEDLINE | ID: mdl-32237519

RESUMO

The aim of this paper was to observe the effect of Di'ao Xinxuekang(DXXK) on TLR4/MyD88/NF-κB signaling pathway in atherosclerotic rats, and to explore its anti-atherosclerotic mechanism. Sixty SD rats were randomly divided into normal group, model group, atorvastatin group(4.0 mg·kg~(-1)), and DXXK groups(100, 30, 10 mg·kg~(-1)), with 10 rats in each group. The atherosclerosis model was induced by high fat diet plus vitamin D_2. Experimental drugs were administered intragastrically once daily for 8 weeks starting from the 9 th week. Biochemical analyzers were used to detect levels of triglyceride(TG), total cholesterol(TC), low-density lipoprotein cholesterol(LDL-C) and high-density lipoprotein cholesterol(HDL-C) in blood lipid. The levels of serum tumor necrosis factor(TNF)-α, interleukin(IL)-6 and IL-1ß were detected by ELISA. Pathological changes of aortic tissues were observed by using Sudan Ⅳ and HE staining. The mRNA and protein expressions of TLR4, MyD88 and NF-κB p65 in aortic tissues were detected by RT-PCR and Western blot, respectively. As compared with the model group, TC, TG, and LDL-C levels in serum were significantly decreased, HDL-C content was significantly increased, and levels of TNF-α, IL-6, and IL-1ß in serum were significantly decreased in atorvastatin group and DXXK high and middle dose groups. Aortic lesions in atorvastatin group and DXXK group were significantly improved, and the mRNA and protein expressions of TLR4, MyD88, NF-κB p65 in the aorta were decreased. DXXK has a preventive and therapeutic effect on atherosclerosis in rats, and its mechanism may be related to inhibiting inflammatory reaction by regulating TLR4/MyD88/NF-κB signal transduction, thereby inhibiting the progression of atherosclerosis.


Assuntos
Aterosclerose/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Transdução de Sinais , Animais , Aorta/patologia , Atorvastatina , Interleucina-6/sangue , Interleucina-8/sangue , Lipídeos/sangue , Fator 88 de Diferenciação Mieloide/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptor 4 Toll-Like/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/sangue
15.
Biophys J ; 116(6): 1136-1151, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30824114

RESUMO

The process of platelet adhesion is initiated by glycoprotein (GP)Ib and GPIIbIIIa receptors on the platelet surface binding with von Willebrand factor on the vascular walls. This initial adhesion and detachment of a single platelet is a complex process that involves multiple bonds forming and breaking and is strongly influenced by the surrounding blood-flow environment. In addition to bond-level kinetics, external factors such as shear rate, hematocrit, and GPIb and GPIIbIIIa receptor densities have also been identified as influencing the platelet-level rate constants in separate studies, but this still leaves a gap in understanding between these two length scales. In this study, we investigate the fundamental relationship of the dynamics of platelet adhesion, including these interrelating factors, using a coherent strategy. We build a, to our knowledge, novel and computationally efficient multiscale model accounting for multibond kinetics and hydrodynamic effects due to the flow of a cellular suspension. The model predictions of platelet-level kinetics are verified by our microfluidic experiments, which systematically investigate the role of each external factor on platelet adhesion in an in vitro setting. We derive quantitative formulas describing how the rates of platelet adhesion, translocation, and detachment are defined by the molecular-level kinetic constants, the local platelet concentration near the reactive surface determined by red-blood-cell migration, the platelet effective reactive area due to its tumbling motion, and the platelet surface receptor density. Furthermore, if any of these aspects involved have abnormalities, e.g., in a disease condition, our findings also have clinical relevance in predicting the resulting change in the adhesion dynamics, which is essential to hemostasis and thrombosis.


Assuntos
Modelos Biológicos , Adesividade Plaquetária , Fator de von Willebrand/metabolismo , Hematócrito , Humanos , Hidrodinâmica , Cinética , Resistência ao Cisalhamento , Propriedades de Superfície
16.
Cell Mol Neurobiol ; 39(1): 111-122, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30511325

RESUMO

Epilepsy is a commonly occurring neurological disease that has a large impact on the patient's daily life. Phosphorylation of heat shock protein B6 (HspB6) has been reported to protect the central nervous system. In this investigation, we explored whether HspB6 played a positive effect on epilepsy with the involvement of the cyclic adenosine monophosphate-protein kinase A (cAMP-PKA) pathway. The epileptic seizure was induced in rats by intraperitoneal injection of kainic acid (KA). The extent of HspB6 phosphorylation and expressions of HspB6, PKA, and inflammatory factors TNF-α, IL-1ß, and IL-6 were quantified along with neuronal apoptosis. To further understand the regulatory mechanism of the HspB6 in the hippocampus, we altered the expression and the extent of HspB6 phosphorylation to see whether the cAMP-PKA pathway was inactivated or not in hippocampal neurons of rats post KA. Results showed that HspB6 was poorly expressed, resulting in the inactivation of the cAMP-PKA pathway in rats post KA, as well as an aggravated inflammatory response and hippocampal neuronal apoptosis. HspB6 overexpression and the cAMP-PKA pathway activation decreased the expression of inflammatory factors and inhibited hippocampal neuronal apoptosis. Additionally, HspB6 phosphorylation further augments the inhibitory effects of HspB6 on the inflammatory response and hippocampal neuronal apoptosis. The cAMP-PKA pathway activation was found to result in increased HspB6 phosphorylation. HspB6 decreased apoptosis signal-regulating kinase 1 (ASK1) expression to inhibit inflammatory response and hippocampal neuronal apoptosis. Collectively, our findings demonstrate that activation of the cAMP-PKA pathway induces overexpression and partial phosphorylation of HspB6 lead to the inhibition of ASK1 expression. This in turn protects rats against epilepsy and provides a potential approach to prevent the onset of epileptic seizure in a clinical setting.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Proteínas de Choque Térmico HSP20/metabolismo , Convulsões/metabolismo , Convulsões/patologia , Transdução de Sinais , Animais , Apoptose , Sequência de Bases , Regulação para Baixo , Hipocampo/patologia , Inflamação/metabolismo , Inflamação/patologia , Ácido Caínico , MAP Quinase Quinase Quinase 5/metabolismo , Masculino , Neurônios/metabolismo , Neurônios/patologia , Fosforilação , Ratos Sprague-Dawley
17.
J Cell Biochem ; 119(4): 3199-3209, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29091295

RESUMO

Schistosomiasis is one of the world's major public health problems in terms of morbidity and mortality, causing granulomatous inflammation and cumulative fibrosis. This study explored in vivo and vitro effects of miR-29b-3p in granulomatous liver fibrosis by targeting COL1A1 and COL3A1 in Schistosoma japonicum infection. Thirty male Balb/c mice were assigned to normal control and model (percutaneous infection of cercariae of S. japonicum) groups. NIH-3T3 mouse embryonic fibroblasts were designated into blank, NC, miR-29b-3p mimic, TGF-ß1, TGF-ß1 + NC, and TGF-ß1 + miR-29b-3p mimic groups. HE and Masson staining were employed to observe the pathological changes and collagenous fibrosis. The expression of α-SMA, COL1A1, COL3A1, TIMP-1 was determined by immunohistochemistry. The RT-qPCR, Western blotting and immunofluorescence staining were conducted to determine expression of miR-29b-3p, COL1A1, and COL3A1. CCK-8 assay and flow cytometry were performed to evaluate viability and apoptosis. The relative expression of miR-29b-3p decreased in the model group. The model group showed marked fibrosis in liver tissues. The expression of α-SMA, COL1A1, COL3A1, TIMP-1 was higher in the model group than that in the normal control group. Dual luciferase reporter gene assay revealed that miR-29b-3p directly targeted COL1A1 and COL3A1. Compared with the blank, NC, TGF-ß1 and TGF-ß1 + NC groups, the miR-29b-3p mimic group exhibited up-regulated expression of miR-29b-3p and MMP-9 but down-regulated expression of TIMP-1, HSP47, α-SMA, COL1A1, and COL3A1; while lower cell viability but higher apoptosis rate showed. It indicated that miR-29b-3p prevents S. japonicum-induced liver fibrosis by inhibiting COL1A1 and COL3A1.


Assuntos
Colágeno Tipo III/genética , Colágeno Tipo I/genética , Cirrose Hepática/parasitologia , MicroRNAs/genética , Esquistossomose Japônica/genética , Animais , Proliferação de Células , Sobrevivência Celular , Colágeno Tipo I/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Colágeno Tipo III/metabolismo , Modelos Animais de Doenças , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Masculino , Camundongos , Células NIH 3T3 , Schistosoma japonicum/patogenicidade , Esquistossomose Japônica/metabolismo
18.
Neurol Sci ; 38(5): 811-817, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28215036

RESUMO

The primary purpose of this study was to assess the serum levels of homocysteine (HCY) at admission to the presence of post-stroke depression (PSD). From September 2014 to December 2015, first-ever acute ischemic stroke patients within the first 24 h after stroke onset were consecutively recruited and followed-up for 3 months. Based on the symptoms, diagnoses of depression were made in accordance with DSM-IV criteria for depression. By the time of 3 month after stroke, 238 had finished the follow-up and included in our study. Totally, 65 out of the 238 patients were diagnosed as depression (27.3%; 95% CI 19.6-35.4%). The results showed significantly higher HCY levels in patients with depression [21.4 (IQR 16.5-23.4) mmol/L vs. 14.1 (IQR 11.2-18.5) mmol/L, P < 0.0001) at admission than patients without depression. In multivariate logistic regression analysis, HCY was an independent predictor of PSD with an adjusted OR of 1.07 (95% CI 1.01-1.22; P = 0.013). Based on the ROC curve, the optimal cut-off value of serum HCY levels as an indicator for prediction of PSD was projected to be 16.5 mmol/L, which yielded a sensitivity of 82.5% and a specificity of 63.6%, with the area under the curve at 0.745 (95% CI 0.672-0.818; P < 0.0001). An increased risk of PSD was associated with serum HCY levels ≥16.5 mmol/L (adjusted OR 6.13, 95% CI 3.32-14.16; P < 0.001) after adjusting for above-recorded confounders. Elevated serum levels of HCY at admission were associated with depression 3-month after stroke, suggesting that these alterations might participate in the pathophysiology of depression symptoms in stroke patients.


Assuntos
Depressão/sangue , Depressão/etiologia , Homocisteína/sangue , Acidente Vascular Cerebral/complicações , Idoso , Isquemia Encefálica/complicações , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Escalas de Graduação Psiquiátrica , Curva ROC , Estatísticas não Paramétricas , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Tomografia Computadorizada por Raios X
19.
Proc Biol Sci ; 283(1822)2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26763710

RESUMO

Antibiotic resistance carries a fitness cost that must be overcome in order for resistance to persist over the long term. Compensatory mutations that recover the functional defects associated with resistance mutations have been argued to play a key role in overcoming the cost of resistance, but compensatory mutations are expected to be rare relative to generally beneficial mutations that increase fitness, irrespective of antibiotic resistance. Given this asymmetry, population genetics theory predicts that populations should adapt by compensatory mutations when the cost of resistance is large, whereas generally beneficial mutations should drive adaptation when the cost of resistance is small. We tested this prediction by determining the genomic mechanisms underpinning adaptation to antibiotic-free conditions in populations of the pathogenic bacterium Pseudomonas aeruginosa that carry costly antibiotic resistance mutations. Whole-genome sequencing revealed that populations founded by high-cost rifampicin-resistant mutants adapted via compensatory mutations in three genes of the RNA polymerase core enzyme, whereas populations founded by low-cost mutants adapted by generally beneficial mutations, predominantly in the quorum-sensing transcriptional regulator gene lasR. Even though the importance of compensatory evolution in maintaining resistance has been widely recognized, our study shows that the roles of general adaptation in maintaining resistance should not be underestimated and highlights the need to understand how selection at other sites in the genome influences the dynamics of resistance alleles in clinical settings.


Assuntos
Farmacorresistência Bacteriana/genética , Pseudomonas aeruginosa/efeitos dos fármacos , Rifampina/farmacologia , Adaptação Biológica , Antibacterianos/farmacologia , Aptidão Genética , Genômica , Pseudomonas aeruginosa/genética
20.
Artigo em Zh | MEDLINE | ID: mdl-30121061

RESUMO

Information on the endemic situation of malaria in the joint malaria control zone of Guizhou and Guangxi Provinces from 2012 to 2013 was collected. Blood test results from fever patients and the healthy population were obtained. The spatiotemperal and occupational distributions of malaria cases were analyzed. During 2012-2013, blood tests were performed in 253 606 local residents and 11 212 returning residents in the joint area, as well as in 19 843 migrants from outside the area, resulting in discovery of 30 Plasmodium-infected cases only in the returning residents. All the 30 cases were imported from abroad, most of whom were electricity workers returning from the Africa. Among them, 28 cases were reported in 6 counties in Guangxi, and 2 in 2 counties/cities in Guizhou.


Assuntos
Malária , África , China , Humanos , Incidência
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