Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
BMC Pediatr ; 24(1): 390, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858617

RESUMO

BACKGROUND: Oculocutaneous albinism (OCA) is a group of autosomal recessive hereditary disorders that affect melanin biosynthesis, resulting in abnormalities in hair, skin, and eyes. Retinopathy of prematurity (ROP) is a proliferative retinopathy mainly observed in premature infants with low birth weight and early gestational age, but it can also affect full-term infants or children with normal weight, particularly in developing countries. The coexistence of ROP and OCA is rare. There is limited documentation regarding treatment approaches, with few studies reporting positive outcomes with laser treatment due to the absence of melanin pigment. This study discusses the treatment challenges in a female infant diagnosed with ROP and OCA, and underscores the importance of genetic analysis in guiding therapeutic decisions for this rare comorbid condition. CASE PRESENTATION: The study presents a case of ROP occurring concurrently with OCA. Genetic testing revealed two variants, c.727C > T (p.R243C) and c.1832 T > C (p.L611P), in the OCA2 gene, inherited from the patient's mother and father, respectively. The identified mutations were consistent with a diagnosis of OCA2, classified as a subtype of OCA. The patient initially received intravitreal anti-vascular endothelial growth factor (anti-VEGF) injection, followed by laser photocoagulation therapy for a recurrent event. A favorable outcome was observed during the 2-month follow-up period. CONCLUSIONS: The co-occurrence of ROP and OCA is a rare phenomenon, and this is the first recorded case in the Chinese population. The current case supports the use of laser as the primary treatment modality for ROP in OCA2 patients with partial pigmentation impairment. Furthermore, genetic analysis can aid in predicting the effectiveness of laser photocoagulation in this patient population.


Assuntos
Albinismo Oculocutâneo , Retinopatia da Prematuridade , Humanos , Feminino , Albinismo Oculocutâneo/genética , Albinismo Oculocutâneo/complicações , Albinismo Oculocutâneo/terapia , Retinopatia da Prematuridade/genética , Retinopatia da Prematuridade/terapia , Retinopatia da Prematuridade/complicações , Recém-Nascido , Proteínas de Membrana Transportadoras/genética , Mutação , Inibidores da Angiogênese/uso terapêutico , Fotocoagulação a Laser , Bevacizumab/uso terapêutico
2.
MMWR Morb Mortal Wkly Rep ; 72(5): 125-127, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36730050

RESUMO

Monitoring emerging SARS-CoV-2 lineages and their epidemiologic characteristics helps to inform public health decisions regarding vaccine policy, the use of therapeutics, and health care capacity. When the SARS-CoV-2 Alpha variant emerged in late 2020, a spike gene (S-gene) deletion (Δ69-70) in the N-terminal region, which might compensate for immune escape mutations that impair infectivity (1), resulted in reduced or failed S-gene target amplification in certain multitarget reverse transcription-polymerase chain reaction (RT-PCR) assays, a pattern referred to as S-gene target failure (SGTF) (2). The predominant U.S. SARS-CoV-2 lineages have generally alternated between SGTF and S-gene target presence (SGTP), which alongside genomic sequencing, has facilitated early monitoring of emerging variants. During a period when Omicron BA.5-related sublineages (which exhibit SGTF) predominated, an XBB.1.5 sublineage with SGTP has rapidly expanded in the northeastern United States and other regions.


Assuntos
COVID-19 , Saúde Pública , Estados Unidos/epidemiologia , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Mutação , Teste para COVID-19
3.
MMWR Morb Mortal Wkly Rep ; 72(24): 651-656, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37319011

RESUMO

CDC has used national genomic surveillance since December 2020 to monitor SARS-CoV-2 variants that have emerged throughout the COVID-19 pandemic, including the Omicron variant. This report summarizes U.S. trends in variant proportions from national genomic surveillance during January 2022-May 2023. During this period, the Omicron variant remained predominant, with various descendant lineages reaching national predominance (>50% prevalence). During the first half of 2022, BA.1.1 reached predominance by the week ending January 8, 2022, followed by BA.2 (March 26), BA.2.12.1 (May 14), and BA.5 (July 2); the predominance of each variant coincided with surges in COVID-19 cases. The latter half of 2022 was characterized by the circulation of sublineages of BA.2, BA.4, and BA.5 (e.g., BQ.1 and BQ.1.1), some of which independently acquired similar spike protein substitutions associated with immune evasion. By the end of January 2023, XBB.1.5 became predominant. As of May 13, 2023, the most common circulating lineages were XBB.1.5 (61.5%), XBB.1.9.1 (10.0%), and XBB.1.16 (9.4%); XBB.1.16 and XBB.1.16.1 (2.4%), containing the K478R substitution, and XBB.2.3 (3.2%), containing the P521S substitution, had the fastest doubling times at that point. Analytic methods for estimating variant proportions have been updated as the availability of sequencing specimens has declined. The continued evolution of Omicron lineages highlights the importance of genomic surveillance to monitor emerging variants and help guide vaccine development and use of therapeutics.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Pandemias , COVID-19/epidemiologia , Genômica
4.
Zhongguo Zhong Yao Za Zhi ; 48(21): 5863-5870, 2023 Nov.
Artigo em Zh | MEDLINE | ID: mdl-38114182

RESUMO

This study aims to investigate the effects of baicalein(BAI) on lipopolysaccharide(LPS)-induced human microglial clone 3(HMC3) cells, with a focus on suppressing inflammatory responses and elucidating the potential mechanism underlying the therapeutic effects of BAI on ischemic stroke via modulating the cAMP-PKA-NF-κB/CREB pathway. The findings have significant implications for the application of traditional Chinese medicine in treating cerebral ischemic diseases. First, the safe dosage of BAI was screened, and then an inflammation model was established with HMC3 cells by induction with LPS for 24 h. The cells were assigned into a control group, a model group, and high-, medium-, and low-dose(5, 2.5, and 1.25 µmol·L~(-1), respectively) BAI groups. The levels of superoxide dismutase(SOD) and malondialdehyde(MDA) in cell extracts, as well as the levels of interleukin-1ß(IL-1ß), IL-6, tumor necrosis factor-α(TNF-α), and cyclic adenosine monophosphate(cAMP) in the cell supernatant, were measured. Western blot was performed to determine the expression of protein kinase A(PKA), phosphorylated cAMP-response element binding protein(p-CREB), and nuclear factor-kappa B p65(NF-κB p65). Hoechst 33342/PI staining was employed to assess cell apoptosis. High and low doses of BAI were used for treatment in the research on the mechanism. The results revealed that BAI at the concentrations of 10 µmol·L~(-1) and below had no impact on normally cultured HMC3 cells. LPS induction at 200 ng·mL~(-1) for 24 h reduced the SOD activity and increased the MDA content in HMC3 cells. However, 5, 2.5, and 1.25 µmol·L~(-1) BAI significantly increased the SOD activity and 5 µmol·L~(-1) BAI significantly decreased the MDA content. In addition, BAI ameliorated the M1 polarization of HMC3 cells induced by LPS, as indicated by cellular morphology. The results of ELISA demonstrated that BAI significantly lowered the levels of TNF-α, IL-1ß, IL-6, and cAMP in the cell supernatant. Western blot revealed that BAI up-regulated the protein levels of PKA and p-CREB while down-regulating the expression of NF-κB p65. Hoechst 33342/PI staining results indicated that BAI mitigated the apoptosis of HMC3 cells. Overall, the results indicated that BAI had protective effects on the HMC3 cells induced by LPS, and could inhi-bit inflammatory response and improve cell apoptosis, which might be related to the regulation of the cAMP-PKA-NF-κB/CREB pathway.


Assuntos
Microglia , NF-kappa B , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Superóxido Dismutase/metabolismo
5.
Emerg Infect Dis ; 28(7): 1442-1445, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35551714

RESUMO

To detect new and changing SARS-CoV-2 variants, we investigated candidate Delta-Omicron recombinant genomes from Centers for Disease Control and Prevention national genomic surveillance. Laboratory and bioinformatic investigations identified and validated 9 genetically related SARS-CoV-2 viruses with a hybrid Delta-Omicron spike protein.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Biologia Computacional , Humanos , SARS-CoV-2/genética , Estados Unidos/epidemiologia
6.
MMWR Morb Mortal Wkly Rep ; 71(6): 206-211, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35143464

RESUMO

Genomic surveillance is a critical tool for tracking emerging variants of SARS-CoV-2 (the virus that causes COVID-19), which can exhibit characteristics that potentially affect public health and clinical interventions, including increased transmissibility, illness severity, and capacity for immune escape. During June 2021-January 2022, CDC expanded genomic surveillance data sources to incorporate sequence data from public repositories to produce weighted estimates of variant proportions at the jurisdiction level and refined analytic methods to enhance the timeliness and accuracy of national and regional variant proportion estimates. These changes also allowed for more comprehensive variant proportion estimation at the jurisdictional level (i.e., U.S. state, district, territory, and freely associated state). The data in this report are a summary of findings of recent proportions of circulating variants that are updated weekly on CDC's COVID Data Tracker website to enable timely public health action.† The SARS-CoV-2 Delta (B.1.617.2 and AY sublineages) variant rose from 1% to >50% of viral lineages circulating nationally during 8 weeks, from May 1-June 26, 2021. Delta-associated infections remained predominant until being rapidly overtaken by infections associated with the Omicron (B.1.1.529 and BA sublineages) variant in December 2021, when Omicron increased from 1% to >50% of circulating viral lineages during a 2-week period. As of the week ending January 22, 2022, Omicron was estimated to account for 99.2% (95% CI = 99.0%-99.5%) of SARS-CoV-2 infections nationwide, and Delta for 0.7% (95% CI = 0.5%-1.0%). The dynamic landscape of SARS-CoV-2 variants in 2021, including Delta- and Omicron-driven resurgences of SARS-CoV-2 transmission across the United States, underscores the importance of robust genomic surveillance efforts to inform public health planning and practice.


Assuntos
COVID-19/epidemiologia , COVID-19/virologia , SARS-CoV-2/genética , Centers for Disease Control and Prevention, U.S. , Genômica , Humanos , Prevalência , Vigilância em Saúde Pública/métodos , Estados Unidos/epidemiologia
7.
Zhongguo Zhong Yao Za Zhi ; 47(4): 1031-1038, 2022 Feb.
Artigo em Zh | MEDLINE | ID: mdl-35285204

RESUMO

This study aims to explore the pharmacodynamic effect of baicalin on rat brain edema induced by cerebral ischemia reperfusion injury and discuss the mechanism from the perspective of inhibiting astrocyte swelling, which is expected to serve as a refe-rence for the treatment of cerebral ischemia with Chinese medicine. To be specific, middle cerebral artery occlusion(suture method) was used to induce cerebral ischemia in rats. Rats were randomized into normal group, model group, high-dose baicalin(20 mg·kg~(-1)) group, and low-dose baicalin(10 mg·kg~(-1)) group. The neurobehavior, brain index, brain water content, and cerebral infarction area of rats were measured 6 h and 24 h after cerebral ischemia. Brain slices were stained with hematoxylin and eosin(HE) for the observation of pathological morphology of cerebral cortex after baicalin treatment. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the content of total L-glutathione(GSH) and glutamic acid(Glu) in brain tissue, Western blot to measure the content of glial fibrillary acidic protein(GFAP), aquaporin-4(AQP4), and transient receptor potential vanilloid type 4(TRPV4), and immunohistochemical staining to observe the expression of GFAP. The low-dose baicalin was used for exploring the mechanism. The experimental results showed that the neurobehavioral scores(6 h and 24 h of cerebral ischemia), brain water content, and cerebral infarction area of the model group were increased, and both high-dose and low-dose baicalin can lower the above three indexes. The content of GSH dropped but the content of Glu raised in brain tissue of rats in the model group. Low-dose baicalin can elevate the content of GSH and lower the content of Glu. According to the immunohistochemical staining result, the model group demonstrated the increase in GFAP expression, and swelling and proliferation of astrocytes, and the low-dose baicalin can significantly improve this situation. The results of Western blot showed that the expression of GFAP, TRPV4, and AQP4 in the cerebral cortex of the model group increased, and the low-dose baicalin reduce their expression. The cerebral cortex of rats in the model group was severely damaged, and the low-dose baicalin can significantly alleviate the damage. The above results indicate that baicalin can effectively relieve the brain edema caused by cerebral ischemia reperfusion injury in rats, possibly by suppressing astrocyte swelling and TRPV4 and AQP4.


Assuntos
Edema Encefálico , Isquemia Encefálica , Animais , Aquaporina 4/genética , Astrócitos , Edema Encefálico/tratamento farmacológico , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Flavonoides , Infarto da Artéria Cerebral Média/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Reperfusão , Canais de Cátion TRPV/uso terapêutico
8.
Zhongguo Zhong Yao Za Zhi ; 47(19): 5284-5291, 2022 Oct.
Artigo em Zh | MEDLINE | ID: mdl-36472035

RESUMO

This study aims to observe the therapeutic effect of salidroside on cerebral ischemia-reperfusion(I/R) model rats, and to specifically explore the protection of salidroside on endothelial cell barrier after I/R and the mechanism. In the experiment, SD rats were randomized into sham group, model group, and high-, medium-, and low-dose(10, 5, and 2.5 mg·kg~(-1)) salidroside groups. The suture method was used to induce I/R in rats. The infarct area, neurobehavioral evaluation, and brain water content were used to evaluate the efficacy of salidroside. As for the experiment on the mechanism, high-dose and low-dose salidroside groups were designed. The pathological morphology was observed based on hematoxylin and eosin(HE) staining, and ultrastructure of vascular endothelial cells based on transmission electron microscopy. The content of nitric oxide(NO) in serum, four indexes of blood coagulation, and the content of von Willebrand factor(vWF) in plasma were measured. Western blot(WB) and immunofluorescence(IF) were employed to determine the expression of tight junction proteins(ZO-1, occluding, and claudin-1) and matrix metalloproteinase 9(MMP-9) in the cortex. The results showed that the model group had obvious neurological deficit, obvious infarct in the right brain tissue, and significant increase in water content in brain tissue compared with the sham group. Compared with the model group, high-dose and low-dose salidroside groups showed decrease in neurobehavioral score, and the high-, medium-, and low-dose salidroside groups demonstrated obviously small infarct area and significant decrease in water content in brain tissue. The results of HE staining and transmission electron microscopy showed that rats had necrosis of neurons, damage of original physiological structure of endothelial cells, and disintegration of the tight junction between endothelial cells after I/R compared with the sham group. Compared with the model group, the high-dose and low-dose salidroside groups showed alleviation of neuron injury and intact physiological structure of endothelial cells. The model group had significantly lower serum level of NO, significantly higher plasma levels of vWF and fibrinogen(FIB), and significantly shorter thrombin time(TT) and prothrombin time(PT) than the sham group. Compared with model group, the high-dose and low-dose salidroside groups increased the serum content of NO in serum, decreased the plasma levels of FIB and vWF, and significantly prolonged TT and PT. WB and IF results showed that the model group had significantly lower levels of ZO-1, occluding, and claudin-1 among endothelial cells and significantly higher level of MMP-9 than the sham group. Compared with the model group, high-dose and low-dose salidroside significantly increased the levels of ZO-1, occluding, and claudin-1 in the cortex. The above experimental results show that salidroside has clear therapeutic effect on I/R rats and protects the brain. To be specific, it alleviates the damage of endothelial cells by increasing NO synthesis in endothelial cells, inhibiting coagulation reaction and MMP-9 expression, up-regulating the expression of ZO-1, occludin, and claudin-1, thereby protecting the brain.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Animais , Ratos , Metaloproteinase 9 da Matriz/metabolismo , Células Endoteliais/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Barreira Hematoencefálica , Claudina-1/metabolismo , Claudina-1/farmacologia , Claudina-1/uso terapêutico , Fator de von Willebrand/metabolismo , Fator de von Willebrand/farmacologia , Fator de von Willebrand/uso terapêutico , Ratos Sprague-Dawley , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Infarto Cerebral , Reperfusão , Água/metabolismo
9.
Mol Phylogenet Evol ; 159: 107119, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33609704

RESUMO

The stinging wasps (Hymenoptera: Aculeata) include diverse groups such as vespid wasps, ants and bees. Phylogenetic relationships among major lineages of stinging wasps have been inferred from molecular and morphological data. However, the genomic features of the mitochondrial genomes and their phylogenetic utility remain to be explored. In this study, we determined 23 mitochondrial genomes from the Aculeata. Four Mutillidae species showed relatively low A + T content compared to other species of the Aculeata (69.7%-77.4%). Eleven out of 44 species, mainly from the Chrysididae and the Pompilidae, showed reversals of GC skews. Gene rearrangements occurred across the species. Patterns of tRNA rearrangement were conserved in some groups, including the Chrysididae, Bethylidae, Pompilidae, Scolioidea and Vespoidea. Rearrangement of protein-coding genes were found in 12 out of 44 species of the Aculeata, including all four species from the Chrysididae, both species from the Bethylidae, one species from the Dryinidae, all three Scolioidea species and two Apoidea species. Phylogenetic inference showed a long branch in species with unusual genomic features, such as in the Mutillidae and Bethylidae. By excluding these species, we found paraphyly of the Chrysidoidea and a sister group relationship between the Formicoidea and Vespoidea. These results improve our understanding of the evolution of mitochondrial genomes in the Aculeata and, in general, the evolution across this subclade.


Assuntos
Rearranjo Gênico , Genoma Mitocondrial , Filogenia , Vespas/classificação , Animais , Evolução Biológica , Genômica
10.
Ecotoxicol Environ Saf ; 208: 111623, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396143

RESUMO

Monitoring the consumption of pharmaceuticals and licit drugs is important for assessing the needs of public health owing to the impact on individuals as well as society. The present work applied wastewater-based epidemiology to profile the spatial patterns of metformin, nicotine, and caffeine use and their correlations. Influent wastewater samples were collected from 27 wastewater treatment plants in 22 typical Chinese cities that covered all geographic regions of the country. The consumption of metformin ranged from 0.02 g/d/1000 inh to 8.92 g/d/1000 inh, whereas caffeine and nicotine consumption ranged from 4.33 g/d/1000 inh to 394 g/d/1000 inh and 0.17 g/d/1000 inh to 1.88 g/d/1000 inh, respectively. There were significant regional differences in the consumption of caffeine, with the highest consumption in East China and the lowest consumption in Northeast China. The consumption and concentration of caffeine were related to the gross domestic product and per capita disposable income of urban residents, respectively. There was a correlation between the concentrations of caffeine and cotinine (a nicotine metabolite), thereby indicating that individuals that use one of these substances are likely to use the other substance. A significant relationship was found between the concentration of metformin and cotinine, thereby implying that the use of tobacco may be correlated with type 2 diabetes. Co-analysis of these substances in wastewater may provide a more accurate picture of substance use situations within different communities and provide more information on human health, human behavior, and the economy. This report describes the newest study related to the consumption of metformin among the general population in China.


Assuntos
Cafeína/análise , Metformina/análise , Nicotina/análise , Uso de Tabaco/epidemiologia , Vigilância Epidemiológica Baseada em Águas Residuárias , Águas Residuárias/química , Cafeína/química , China/epidemiologia , Cidades , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Nicotina/química , Análise Espacial , Nicotiana , Águas Residuárias/análise
11.
Zhongguo Zhong Yao Za Zhi ; 46(20): 5226-5232, 2021 Oct.
Artigo em Zh | MEDLINE | ID: mdl-34738423

RESUMO

Buyang Huanwu Decoction, a representative prescription in traditional Chinese medicine(TCM) for tonifying Qi and activating blood, has been proved to be effective in preventing and treating acute cerebral infarction(ACI). It consists of Astragali Radix, Angelicae Sinensis Radix, Paeoniae Radix Rubra, Pheretima, Chuanxiong Rhizoma, Carthami Flos, and Persicae Semen, possessing multiple active ingredients. The neurovascular unit is a functionally and structurally interdependent multicellular complex composed of neurons-glial cells-blood vessels. It plays an important role in the pathological changes of cerebral ischemia and the permeability variation of the blood-brain barrier. In recent years, Buyang Huanwu Decoction has been found to protect the integrity of neurovascular units and improve the permeability of the blood-brain barrier, thereby alleviating stroke and other diseases caused by cerebral ischemia. This paper collated and summarized the protective effects of Buyang Huanwu Decoction on neurovascular units.


Assuntos
Isquemia Encefálica , Medicamentos de Ervas Chinesas , Isquemia Encefálica/tratamento farmacológico , Infarto Cerebral , Humanos , Medicina Tradicional Chinesa
12.
BMC Pediatr ; 20(1): 465, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33023519

RESUMO

BACKGROUND: Congenital nasolacrimal duct obstruction (CNLDO) is one of the main causes of epiphora in infants, and antibiotics are usually used as a conservative therapy in the first year. Yet, little is known about the bacteriology of the occluded lacrimal drainage system in this group of patients. The aim of this study was to evaluate the microbiology of lacrimal sac (LS) in Chinese children with CNLDO in their first year of life. METHODS: Patients with CNLDO between May 1, 2017 and August 31, 2018 at a tertiary care children's hospital were enrolled. The study recruited infants who received lacrimal probing under 1 year old, and refluxed discharge from LS was collected. Samples were cultured and susceptibility test was performed for positive culture. RESULTS: Thirty-two patients with CNLDO were included. The ratio of male to female was 23:9. The mean age was 6.7 ± 2.4 (1.7-12) months. Positive cultures was identified in 87.5% of the sample, and presented 38 strains of bacteria. Mixed infection was identified in 10 (31.3%) children. Gram-positive bacteria accounted for 60.5% of all the strains, with Streptococcus (50%) being the most frequent species, whereas Haemophilus (21.1%) and Neisseriae (13.2%) were most common isolates for Gram-negative organisms. Methicillin-resistant Staphylococcus aureus (MRSA) was detected in 2 infants whose symptoms resolved by a routine probing. No difference of bacteriology pattern was detected between patients under 6 months old and those beyond. The pathogens were highly sensitive to chloramphenicol (88%) and levofloxacin (84%), but resistant to erythromycin (40%) and sulfamethoxazole (32%). CONCLUSIONS: Infants with CNLDO under 1 year of age presented predominance of Streptococcus as Gram-positive organism, and Haemophilus as Gram-negative organism. Levofloxacin was an active topical antibiotic agent with few chance of resistance especially for Chinese children. These findings could help clinicians choose optimal medicine for CNLDO as the conservative treatments.


Assuntos
Bacteriologia , Dacriocistorinostomia , Obstrução dos Ductos Lacrimais , Staphylococcus aureus Resistente à Meticilina , Ducto Nasolacrimal , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Obstrução dos Ductos Lacrimais/diagnóstico , Masculino , Estudos Retrospectivos
13.
Proc Natl Acad Sci U S A ; 112(30): 9166-73, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26139525

RESUMO

The plant hormone salicylic acid (SA) is essential for local defense and systemic acquired resistance (SAR). When plants, such as Arabidopsis, are challenged by different pathogens, an increase in SA biosynthesis generally occurs through transcriptional induction of the key synthetic enzyme isochorismate synthase 1 (ICS1). However, the regulatory mechanism for this induction is poorly understood. Using a yeast one-hybrid screen, we identified two transcription factors (TFs), NTM1-like 9 (NTL9) and CCA1 hiking expedition (CHE), as activators of ICS1 during specific immune responses. NTL9 is essential for inducing ICS1 and two other SA synthesis-related genes, phytoalexin-deficient 4 (PAD4) and enhanced disease susceptibility 1 (EDS1), in guard cells that form stomata. Stomata can quickly close upon challenge to block pathogen entry. This stomatal immunity requires ICS1 and the SA signaling pathway. In the ntl9 mutant, this response is defective and can be rescued by exogenous application of SA, indicating that NTL9-mediated SA synthesis is essential for stomatal immunity. CHE, the second identified TF, is a central circadian clock oscillator and is required not only for the daily oscillation in SA levels but also for the pathogen-induced SA synthesis in systemic tissues during SAR. CHE may also regulate ICS1 through the known transcription activators calmodulin binding protein 60g (CBP60g) and systemic acquired resistance deficient 1 (SARD1) because induction of these TF genes is compromised in the che-2 mutant. Our study shows that SA biosynthesis is regulated by multiple TFs in a spatial and temporal manner and therefore fills a gap in the signal transduction pathway between pathogen recognition and SA production.


Assuntos
Arabidopsis/imunologia , Resistência a Medicamentos , Regulação da Expressão Gênica de Plantas , Nicotiana/imunologia , Imunidade Vegetal , Ácido Salicílico/química , Arabidopsis/genética , Ritmo Circadiano , Microscopia Confocal , Mutação , Oscilometria , Fenótipo , Doenças das Plantas/imunologia , Folhas de Planta , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estômatos de Plantas/metabolismo , Regiões Promotoras Genéticas , Transdução de Sinais , Fatores de Tempo , Nicotiana/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Técnicas do Sistema de Duplo-Híbrido
14.
Neurochem Res ; 42(8): 2191-2207, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28397068

RESUMO

Transplantation of human amniotic mesenchymal stem cells (hAM-MSCs) seems to be a promising strategy for the treatment of neurodegenerative disorders, including Alzheimer's disease (AD). However, the clinical therapeutic effects of hAM-MSCs and their mechanisms of action in AD remain to be determined. Here, we used amyloid precursor protein (APP) and presenilin1 (PS1) double-transgenic mice to evaluate the effects of hAM-MSC transplantation on AD-related neuropathology and cognitive dysfunction. We found that hAM-MSC transplantation into the hippocampus dramatically reduced amyloid-ß peptide (Aß) deposition and rescued spatial learning and memory deficits in APP/PS1 mice. Interestingly, these effects were associated with increasing in Aß-degrading factors, elevations in activated microglia, and the modulation of neuroinflammation. Furthermore, enhanced hippocampal neurogenesis in the subgranular zone (SGZ) of the dentate gyrus (DG) and enhanced synaptic plasticity following hAM-MSC treatment could be another important factor in reversing the cognitive decline in APP/PS1 mice. Instead, the mechanism underlying the improved cognition apparently involves a robust increase in hippocampal synaptic density and neurogenesis that is mediated by brain-derived neurotrophic factor (BDNF). In conclusion, our data suggest that hAM-MSCs may be a new and effective therapy for the treatment of AD.


Assuntos
Líquido Amniótico/fisiologia , Peptídeos beta-Amiloides/metabolismo , Transtornos da Memória/metabolismo , Transtornos da Memória/terapia , Memória/fisiologia , Transplante de Células-Tronco Mesenquimais/tendências , Líquido Amniótico/citologia , Precursor de Proteína beta-Amiloide/genética , Animais , Células Cultivadas , Masculino , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/genética , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Presenilina-1/genética
15.
Biochem Cell Biol ; 93(3): 180-4, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25557738

RESUMO

Autophagy is a dynamic process accomplished by the generation and maturation of autophagosomes. Isolation of autophagosomes and subsequent compositional analysis can provide information about their biogenesis mechanism. In this article, HEK293 cells expressing GFP-LC3 were treated by calcium phosphate precipitates (CPP) to induce autophagy. The autophaogomes induced by CPP were tubular and vesicular structures, extensively formed in the cytosol. After all membranes in the cell lysate were fractionated by differential centrifugation, autophagosomes from light and heavy membranes were isolated by immuno-precipitation, using antibodies against GFP-LC3 and Atg5. We found that GFP-LC3 and Atg5 positive autophagosomes represented distinctive subpopulations. Judged from the molecular markers associated, including organelle markers and Atg proteins, GFP-LC3 positive autophagosomes were overall at the later biogenetic stage. Furthermore, both GFP-LC3 and Atg5 positive autophagosomes from light membranes were less mature than those from heavy membranes. We have established a method to isolate subpopulations of autophagsomes for further characterization.


Assuntos
Autofagia , Células HEK293/citologia , Fagossomos , Anticorpos Monoclonais , Autofagia/efeitos dos fármacos , Proteína 5 Relacionada à Autofagia , Cálcio , Fosfatos de Cálcio/farmacologia , Contagem de Células , Centrifugação com Gradiente de Concentração , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Membranas Intracelulares , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/imunologia , Proteínas Associadas aos Microtúbulos/metabolismo , Fagossomos/metabolismo
16.
Graefes Arch Clin Exp Ophthalmol ; 253(12): 2309-15, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26335535

RESUMO

BACKGROUND: To study the inhibition of retinoblastoma cell viability by two commonly used autophagy inhibitors, chloroquine (CQ) and 3-methyladenine (3-MA), alone or in combination with the conventional chemotherapeutic drug vincristine (VCR), and to investigate whether the mechanisms of these drugs are related to inhibition of autophagy. METHODS: On retinoblastoma cell line HXO-Rb44, VCR, CQ and 3-MA were used individually or combined. The cell viability was determined by CCK8 method, and the cellular autophagic activity was determined by Western blotting of LC3 and p62. Caspase 3 fragmentation and Akt activation was also determined by Western blotting. RESULTS: VCR induced cell cycle arrest and apoptosis in HXO-Rb44 cells, but only inhibited autophagy at relatively high doses. Both CQ and 3-MA were synergistic with VCR to inhibit the growth of retinoblastoma cells and the combinational use significantly reduced the dosage of each drug. The lowest effective dose of CQ and 3-MA was most efficient to add on VCR; however, such dose was not sufficient to suppress autophagy in these cells. CQ could directly induce caspase activation, while 3-MA significantly inhibited Akt phosphorylation. CONCLUSIONS: CQ and 3-MA were synergistic with VCR to inhibit retinoblastoma cells. Our result suggested a novel strategy to combine CQ or 3-MA with VCR to reduce the side effects of each drug. However, lack of change in the autophagic activity when using the two drugs at lower doses suggests multiple mechanisms of action of the same drug at different doses. At higher doses, the drugs could inhibit autophagy, while at lower doses, they suppress tumor growth via autophagy-independent mechanisms.


Assuntos
Adenina/análogos & derivados , Antineoplásicos Fitogênicos/farmacologia , Cloroquina/farmacologia , Neoplasias da Retina/patologia , Retinoblastoma/patologia , Vincristina/farmacologia , Adenina/administração & dosagem , Adenina/farmacologia , Antirreumáticos/administração & dosagem , Antirreumáticos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Western Blotting , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cloroquina/administração & dosagem , Sinergismo Farmacológico , Quimioterapia Combinada , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Neoplasias da Retina/metabolismo , Retinoblastoma/metabolismo , Sincalida/metabolismo , Células Tumorais Cultivadas
17.
Ying Yong Sheng Tai Xue Bao ; 35(4): 1112-1122, 2024 Apr 18.
Artigo em Zh | MEDLINE | ID: mdl-38884246

RESUMO

River water quality is influenced by natural processes and human activities. Multi-scale landscape patterns can affect river water quality by altering the generation and transport processes of pollutants at different spatial scales. Taking Taizi River Basin in Northeast China as an example, we analyzed the relationship between landscape patterns and non-point source pollution in rivers based on water quality monitoring data and land use data by using correlation analysis and redundancy analysis methods. We aimed to determine the key spatial scales for the responses of landscape patterns to non-point source pollution and identify the key landscape indices influencing river non-point source pollution. The results showed that water quality of Taizi River Basin had seasonal differences, with better water quality during the flood season than non-flood season. Spatially, total nitrogen (TN) and total phosphorus (TP) were higher at the confluence points of tributaries and downstream areas. The impact of landscape patterns on non-point source pollution was stronger during the non-flood season than the flood season, while the influence on TN was stronger than on TP. At the spatial scale of within 500 m buffer zone during the flood season and at the sub-watershed scale during the non-flood season, landscape patterns showed the highest explanatory power for the variations of TN and TP. At the type level, built-up land, cropland, and bare land were positively correlated with TN and TP, while forest was negatively correlated with TN and TP, which were the key types influencing non-point source pollution. At the landscape level, patch density, percentage of like adjacencies, and contagion index were key indicators affecting watershed water quality. Lower patch density was associated with better connectivity and aggregation of "sink" landscapes, leading to better purification effects on TN, but more pronounced retention effects on TP. Conversely, higher landscape diversity and denser pattern of multiple types would cause the deterioration of water quality. Our results suggested that rational allocation of landscape types within the watershed and riparian buffer zones, appropriately enriching landscape diversity, and optimizing landscape aggregation and connectivity would be effective measures for improving water quality and achieving sustainable ecological management.


Assuntos
Monitoramento Ambiental , Fósforo , Rios , Poluentes Químicos da Água , China , Rios/química , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Fósforo/análise , Ecossistema , Nitrogênio/análise , Poluição Difusa/análise , Poluição Difusa/prevenção & controle , Qualidade da Água , Análise Espacial
18.
Sci Rep ; 13(1): 22055, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087043

RESUMO

Analyzing the influence of the bed allocation and utilization efficiency in healthcare institutions on the isolation proportion of Multidrug-resistant organisms (MDROs) to provide data to support prevention and control of MDROs. In this study, the provincial panel data from 2014 to 2020 in China on health resource indicators, including the number of beds per 1,000 population, hospital bed utilization rate, and average hospital stay from 2014 to 2020 in China were used to analyze the relationship between bed allocation or utilization efficiency and MDROs by the panel data quantile regression model. It was shown that the number of beds per 1,000 population had a negative effect on the isolation proportion of methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecalis, vancomycin-resistant Enterococcus faecium, penicillin-resistant Streptococcus pneumoniae, methicillin-resistant coagulase-negative Staphylococcus, and cefotaxime or ceftriaxone resistant Escherichia coli (regression coefficient < 0, P < 0.05). The utilization rate of hospital bed had a positive effect on the isolation proportion of methicillin-resistant Staphylococcus aureus, methicillin-resistant coagulase-negative Staphylococcus, vancomycin-resistant Enterococcus faecium, penicillin-resistant Streptococcus pneumoniae, cefotaxime or ceftriaxone resistant Escherichia coli, carbapenem-resistant Escherichia coli, cefotaxime or ceftriaxone resistant Klebsiella pneumoniae, carbapenem-resistant Klebsiella pneumoniae, carbapenem-resistant Pseudomonas aeruginosa, and carbapenem-resistant Acinetobacter baumannii (regression coefficient > 0, P < 0.05). The average hospital stay had a positive effect on the isolation proportion for several antibiotic-resistant organisms, including methicillin-resistant Staphylococcus aureus, methicillin-resistant coagulase-negative Staphylococcus, vancomycin-resistant Enterococcus faecalis, vancomycin-resistant Enterococcus faecium, penicillin-resistant Streptococcus pneumoniae, cefotaxime or ceftriaxone resistant Escherichia coli, carbapenem-resistant Escherichia coli, quinolone-resistant Escherichia coli, cefotaxime or ceftriaxone resistant Klebsiella pneumoniae, carbapenem-resistant Pseudomonas aeruginosa, and carbapenem-resistant Acinetobacter baumannii (regression coefficient > 0, P < 0.05). Bed allocation and utilization efficiency in healthcare institutions may affect the isolation proportion of MDROs in varying degrees.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Farmacorresistência Bacteriana Múltipla , Vancomicina/farmacologia , Ceftriaxona/farmacologia , Coagulase , Antibacterianos/farmacologia , Cefotaxima/farmacologia , Carbapenêmicos/farmacologia , Escherichia coli , Atenção à Saúde , Penicilinas/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana
20.
World J Pediatr Surg ; 5(3): e000408, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36475049

RESUMO

Background: Multiple chalazia are common in children, and many are treated by surgery. However, the distribution of different types of multiple chalazia has not been studied. This research aimed to investigate the location and number of multiple chalazia in pediatrics who need surgical treatments. Methods: Patients with multiple chalazia treated by incision and curettage surgery (I&C) in a tertiary children's hospital between June and December 2016 were reviewed. Demographic data, locations, and numbers of chalazia were recorded. Data were analyzed using generalized linear models of the counts and the occurrences of chalazia. Hypotheses were tested using likelihood ratio tests appropriate for each type of data. Results: The study included 128 subjects, most of which were 1-3 years old. The majority of patients had bilateral chalazia (95.3%), and the proportions of patients with internal, external, and marginal chalazion differed dramatically (99.2%, 61.7%, and 2.3%, respectively). The number of internal and external chalazia did not vary significantly with gender, age, or residence of the patients. Internal chalazia were located more frequently in the upper lids (p<0.001). External chalazia showed no preference of localization. The average number of internal chalazia in each eyelid did not relate to the presence of external chalazia. Conclusions: Multiple chalazia are common among younger children in southeast China. The anatomical distribution varies depending on the type of chalazion. Multiple chalazia often occur bilaterally and internally. If doctors are more aware of the anatomical distribution of chalazia, this might result in a higher success rate of I&C.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa