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1.
J Cell Physiol ; 235(1): 185-193, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31190335

RESUMO

Cervical cancer (CC) is a prevalent malignancy in women, with the feature of metastasis and easy recurrence is responsible for a large proportion of global cancer deaths. Radiotherapy is one of the common treatment tools for CC patients with unresectable tumors. However, radio-resistance in patients could be a major reason for recurrence. Therefore, it is of significance to tunnel the molecular mechanism of radio-resistance in CC. MicroRNAs (miRNAs) are increasingly reported in the regulation of cancer progression and cellular response to radiotherapy and chemotherapy. miR-4429 is a newly discovered miRNA acting as a tumor-suppressor gene in multiple cancers, but its function in CC has never been explored yet. The current study tried to explore the role of miR-4429 in cell radio-sensitivity in CC. First, we validated the downregulation of miR-4429 in CC cells. Importantly, the association of miR-4429 with radio-resistance was validated by identifying the downregulation of miR-4429 in radio-resistant CC cells. Gain- and loss-of-function assays validated that miR-4429 sensitized CC cells to irradiation. Through bioinformatics tools, RAD51 recombinase (RAD51) was identified to be a target for miR-4429. RAD51 is known to be a crucial regulator for DNA damage repair and has been reported to influence cell radio-resistance in cancers, including in CC. Luciferase reporter assay confirmed the interaction between miR-4429 and RAD51. Finally, rescue assays indicated that miR-4429 promoted CC cell radio-sensitivity through RAD51. Consequently, our study showed that miR-4429 sensitized CC cells to irradiation by targeting RAD51, providing a potential therapeutic target for CC patients.

2.
Mater Sci Eng C Mater Biol Appl ; 106: 110302, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753337

RESUMO

Nanotherapeutics and nanopharmaceuticals could achieve and facilitate earlier and more precise individual diagnosis, improve targeted therapies, reduce side effects, and enhance therapeutic monitoring. These advantages will improve quality of life, support a healthier and more independent aging population, and be instrumental in maximizing the cost-effectiveness of health care. However, the field of nanomedicine is at its early stage, most of the research still stays in the laboratory phase, and few success stories are translated into clinical trials and medical practice. This review will demonstrate the numerous challenges that are encountered during the development of commercial nanoparticle-based therapeutics and the possible solutions.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31691277

RESUMO

OBJECTIVE: To assess the risk of adverse fetal outcomes after exposure to oral antifungal agents during pregnancy. SEARCH STRATEGY: PubMed, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched up to October 2018. SELECTION CRITERIA: Cohort studies and case-control studies investigating fetal outcomes following maternal exposure to oral antifungal agents. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed studies for inclusion, assessed risk of bias, and extracted data. Pooled estimates were calculated for the frequency of adverse fetal outcomes. MAIN RESULTS: Overall, eight cohort studies and one case-control study were included. The oral antifungal agents used during pregnancy were fluconazole and itraconazole. The data indicated that oral fluconazole exposure during pregnancy might slightly increase the risk of congenital heart defects and limb defects relative to the general population; oral itraconazole during pregnancy might increase the risk of eye defects. No difference was found between oral fluconazole/itraconazole exposure and non-exposure in the risk of other birth defects, spontaneous abortion, or stillbirth. CONCLUSION: Oral fluconazole or itraconazole may not increase the risk of birth defects. Nonetheless, the risk of congenital heart defects and limb defects after fluconazole exposure and eye defects after itraconazole exposure should be cautiously investigated.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31755203

RESUMO

Palladium-catalyzed asymmetric [4 + 3] cyclization of trimethylenemethane donors with benzofuran-derived azadienes has been established, furnishing chiral benzofuro[3,2-b]azepine frameworks in high yields (up to 98%) with exclusive regioselectivities and excellent stereoselectivities (up to >20:1 dr, >99% ee). This reaction represents the first catalytic asymmetric [4 + 3] cyclization of Pd-trimethylenemethane (Pd-TMM), which would enrich arsenal of Pd-TMM chemistry in organic synthesis. In addition, this strategy provides an alternative approach to chiral azepines via transition metal-catalyzed asymmetric [4 + 3] cyclization for the first time.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31707608

RESUMO

To clarify the impact of biochar amendment on soil sorption for coexisting pharmaceuticals, wheat straw-derived biochars pyrolyzed at 300 and 700 °C (labeled as WS300 and WS700, respectively) were prepared. Batch experiments on ketoprofen (KTP), atenolol (ATL) and carbamazepine (CBZ) sorption to biochars, loessial soil and biochar-amended soils were conducted. The results indicated that sorption affinity of different species of pharmaceuticals to WS300 and WS700 was in the order of cationic ATL > neutral CBZ > anionic KTP. Cationic ATL had the highest sorption to biochars due to electrostatic attraction. Coexisting ATL, CBZ and KTP competed for the shared adsorption sites on carbonized phase of biochars, and π-π interactions were proposed to be the main sorption mechanism. Sorption coefficients (Kd) and nonlinearity of ATL, CBZ and KTP to soil increased when biochar was added (5% by weight), especially for WS700 with higher specific surface area. Kd values of the three pharmaceuticals to WS700-amended soil in either single solute or bisolute system were one to two orders of magnitude higher than those to soil, indicating the promoting role of WS700 in sorption of coexisting pharmaceuticals in soil. The study demonstrated the enhanced and competitive sorption of ionic and neutral species of pharmaceuticals to soil amended with biochars, which is helpful in designing biochar as effective sorbents for immobilization of pharmaceuticals in soil remediation.

6.
J Org Chem ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31696709

RESUMO

A copper-catalyzed annulation of alkyne-tethered enaminones for the synthesis of 2,3-ring fused pyrroles is reported. The 5-exo-dig cyclization/olefin migration reaction delivers the multisubstituted pyrroles in 59-99% yields with 16 examples. This strategy features easily available starting materials, mild reaction conditions, and a cheap ligand-free copper catalyst. The atom-economic transformation provides a simple access to a variety of synthetic useful pyrroles and their derivatives.

7.
Medicine (Baltimore) ; 98(44): e17797, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689857

RESUMO

RATIONALE: Acute necrotizing encephalopathy (ANE) is a rapidly progressing disease associated with frequent neurologic sequelae and has poor prognosis. Currently, the diagnosis and treatment of ANE rely on neuroradiologic findings and offering supportive care. Here, we report the successful treatment of a teenager diagnosed with ANE using combination of high-dose methylprednisolone and oseltamivir. PATIENT CONCERNS: The patient, a 15-year-old female, presented with impaired consciousness and seizures secondary to acute upper respiratory tract infection. A series of brain magnetic resonance images (MRIs) were obtained toward establishing a possible diagnosis. DIAGNOSIS: Based on the history of presenting illness and subsequent brain MRI scans, the patient was diagnosed to be suffering from ANE. INTERVENTIONS: Following the diagnosis, the patient was placed on therapy comprising of high-dose methylprednisolone and oseltamivir. OUTCOMES: After treatment with methylprednisolone and oseltamivir for 15 days, the patient recovered nearly completely from ANE as confirmed by subsequent brain MRI scans. No complications or other emerging clinical symptoms were noted for the duration of follow-up that lasted 6 months. LESSONS: Contrary to common reports, ANE can occur beyond pediatric populations and its treatment should not be restricted to supportive care. Our case suggests that the use of high-dose corticosteroids and oseltamivir leads to promising prognosis.


Assuntos
Encéfalo/diagnóstico por imagem , Encefalite Viral/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Infecções Respiratórias/complicações , Convulsões/diagnóstico por imagem , Adolescente , Corticosteroides/uso terapêutico , Antivirais/uso terapêutico , Encéfalo/patologia , Encéfalo/virologia , China , Encefalite Viral/tratamento farmacológico , Encefalite Viral/virologia , Feminino , Humanos , Necrose/diagnóstico por imagem , Necrose/virologia , Oseltamivir/uso terapêutico , Prognóstico , Infecções Respiratórias/virologia , Convulsões/patologia , Convulsões/virologia
8.
Nanotechnology ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31766034

RESUMO

The antioxidant activity of Ceria nanoparticles is tightly regulated by size distribution and heteroatom doping. Inspired by this rule, cerium and praseodymium codoped carbon quantum dots (Ce/Pr-CQDs) were synthesized through one-pot hydrothermal carbonization method. Taking intrinsic advantage of CQDs, the resultant Ce/Pr-CQDs exhibited uniform and ultra-small morphology with an average size of 2.8 nm, which could lead to an increased proportion of Ce3+. In addition, the doping of Pr into Ce-CQDs improved redox properties. As we expected, the Ce/Pr-CQDs possessed enhanced hydroxyl radical scavenging properties compared with the cerium-doped carbon quantum dots (Ce-CQDs). Furthermore, Ce/Pr-CQDs with favorable biocompatibility and negligible cytotoxicity are readily internalized into cytoplasm and decreased the level of reactive oxygen species (ROS). Taken together, the resultant Ce/Pr-CQDs displayed great potential application in oxidative stress associated disease.

9.
BMC Pediatr ; 19(1): 409, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31684904

RESUMO

BACKGROUND: To explore the changes of inflammatory and oxidative stress responses in Henoch-Schönlein purpura (HSP) children, and further analyzed the therapeutic effects and mechanisms of hemoperfusion (HP) on HSP with severe gastrointestinal (GI) involvement. METHODS: There were 200 children with HSP were divided into three groups according to their clinical manifestations: 60 in HSP without GI and renal involvement group, 60 in HSP with GI involvement group, and 80 in HSPN group. The HSP with GI involvement group was subdivided into conventional treatment (n = 30) and HP (n = 30) groups. Thirty children who visited the department of children healthcare for healthy physical examinations from January to December 2017 were set as healthy control group. The IL-6 and TNF-α levels were detected by chemoluminescence method. The MDA, SOD and T-AOC levels were determined by thiobarbituric acid colorimetric method, hydroxylamine method and chemical colorimetry. RESULTS: Compared with healthy group, IL-6, TNF-α and MDA levels in HSP were increased in each group, while SOD and T-AOC were decreased (P = 0.000). IL-6, TNF-α and MDA levels in the HSPN group were the highest, SOD and T-AOC levels were the lowest (P = 0.000). Compared with those before treatment, IL-6, TNF-α and MDA levels in the conventional and HP groups were decreased and SOD and T-AOC levels were increased (P = 0.000). The changes in HP group were more significant than those in conventional group (P < 0.047). Compared with conventional group, glucocorticoid dosage and the occurrence rate of hematuria and/or proteinuria within 3 months were lower in HP group. (P = 0.000, 0.004). CONCLUSIONS: Inflammatory and oxidative stress may be involved in the acute phase of HSP children. The intensity of inflammatory and oxidative stress responses were related to the degree of renal involvement. HP can reduce glucocorticoid dosage and the rate of renal involvement in children with severe HSP with GI involvement. The mechanism may be related to the fact that HP can effectively remove IL-6, TNF-α, MDA in HSP children.

10.
J Cell Mol Med ; 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31705584

RESUMO

The modified Wenyang Huayu decoction has been widely used to treat vascular dementia in China for thousands of years. We have previously proved that a modified version, Wuzang Wenyang Huayu decoction has the potential to be a more effective clinical treatment that can attenuate cerebral ischaemic injury. However, the global transcript profile and signalling conduction pathways regulated by this recipe remains unclear. This study established a two-vessel occlusion rat model by bilateral common carotid artery occlusion. Two groups of rats were intragastrically treated Wuzang Wenyang Huayu 2.5 g/kg vs or Piracetam 0.15 g/kg for 2 weeks. Learning and memory abilities were measured with Morris water maze. Neuronal plasticity was observed by HE staining. Differentially expressed transcripts of rat hippocampus were analysed by transcriptomics with Illumina HiSeq2500 platform. Results showed that Wuzang Wenyang Huayu decoction significantly alleviated learning, memory deficits, coordination dysfunction and prevented hippocampus cellular injury; Results further revealed the increased gene expression in KEGG metabolic pathways (MT-ND2. MT-ND3, MT-ND4, MT-ND4L, MT-ND5 and MT-ATP8) and genes involved in signal transduction, carcinogenesis, immune system, endocrine system, nervous system etc (Results further revealed differential expression of genes involved in various systems, including MT-ND2) Our discovery is likely to provide new insights to molecular mechanisms of Wuzang Wenyang Huayu regarding hippocampal transcripts in a murine vascular dementia model.

11.
Pediatrics ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31732547

RESUMO

BACKGROUND: Coronary artery aneurysms (CAAs) are a well-known complication of Kawasaki disease (KD), but there are no data on incidence or outcomes of systemic artery aneurysms (SAAs) in the current era. METHODS: From April 1, 2016, to March 31, 2019, we screened for SAAs in 162 patients with KD at risk for SAAs with magnetic resonance angiography or peripheral angiography and analyzed incidence and early outcomes of SAAs. RESULTS: Twenty-three patients had SAAs, demonstrating an incidence of 14.2% (23 of 162) in patients who were screened at 1 month after onset. The proportion of patients with SAAs was estimated to be 2% (23 of 1148) of all patients with KD. The median age at onset of KD with SAAs was 5 months. All patients with SAAs had CAAs, with z scores >8. Of patients with giant CAAs, 38.6% (17 of 44) had SAAs. A total of 129 SAAs occurred in 17 different named arteries. The most common sites for SAAs were the axillary (18.6%), common iliac (12.4%), and brachial (11.6%) arteries. During a median follow-up time of 6 months, 92.9% (79 of 85) of SAAs had some degree of regression, with 80% (68 of 85) of SAAs returning to normal. The overall regression rate was higher for medium to large SAAs than for medium to giant CAAs. CONCLUSIONS: Although the incidence of SAAs may not be as dramatically reduced as we expected compared with previous data, SAAs have a high regression rate during short-term follow-up.

12.
Lung Cancer ; 139: 118-123, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31775086

RESUMO

OBJECTIVES: The 2015 World Health Organization classification defines pulmonary large-cell neuroendocrine carcinoma (LCNEC) as a high-grade neuroendocrine carcinoma. However, the clinical characteristics and prognostic factors of pure LCNEC and combined LCNEC remain unclear. Hence, we performed a multi-center retrospective study to compare the clinical outcomes of pure versus combined LCNEC. MATERIALS AND METHODS: Data from 381 patients with pulmonary LCNEC admitted to 17 Chinese institutes between 2009 and 2016 were collected retrospectively. Clinical characteristics and prognosis were analyzed among patients receiving adjuvant (adjuvant group; n = 56) and first-line (first-line group; n = 146) chemotherapy, as well as among patients receiving small cell lung cancer (SCLC) and non-SCLC (NSCLC) chemotherapy regimens. The Kaplan-Meier method and multivariable Cox regression were used to identify clinicopathological variables that might influence patient outcomes. RESULTS: Expression levels of neuroendocrine markers (synaptophysin, chromogranin-A, CD56) were associated with patients' prognosis in the total study cohort. In the adjuvant group, median disease-free survival was non-significantly longer for SCLC-based regimens than for NSCLC-based regimens (P = 0.112). In the first-line group, median progression-free survival was significantly longer for SCLC-based regimens than for NSCLC-based regimens (11.5 vs. 7.2 months, P = 0.003). Among patients with combined LCNEC, adenocarcinoma was the most common combined component, accounting for 70.0 % of cases. Additionally, median overall survival was non-significantly shorter for combined LCNEC than for pure LCNEC (P = 0.083). CONCLUSION: The SCLC regimen is a more effective choice, as either first-line or adjuvant chemotherapy, when compared to the NSCLC regimen for LCNEC treatment. Further studies are needed to clarify the survival differences between patients with pure-, and combined LCNEC.

13.
Nature ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776512

RESUMO

Bile acids are abundant in the mammalian gut, where they undergo bacteria-mediated transformation to generate a large pool of bioactive molecules. Although bile acids are known to affect host metabolism, cancer progression and innate immunity, it is unknown whether they affect adaptive immune cells such as T helper cells that express IL-17a (TH17 cells) or regulatory T cells (Treg cells). Here we screen a library of bile acid metabolites and identify two distinct derivatives of lithocholic acid (LCA), 3-oxoLCA and isoalloLCA, as T cell regulators in mice. 3-OxoLCA inhibited the differentiation of TH17 cells by directly binding to the key transcription factor retinoid-related orphan receptor-γt (RORγt) and isoalloLCA increased the differentiation of Treg cells through the production of mitochondrial reactive oxygen species (mitoROS), which led to increased expression of FOXP3. The isoalloLCA-mediated enhancement of Treg cell differentiation required an intronic Foxp3 enhancer, the conserved noncoding sequence (CNS) 3; this represents a mode of action distinct from that of previously identified metabolites that increase Treg cell differentiation, which require CNS1. The administration of 3-oxoLCA and isoalloLCA to mice reduced TH17 cell differentiation and increased Treg cell differentiation, respectively, in the intestinal lamina propria. Our data suggest mechanisms through which bile acid metabolites control host immune responses, by directly modulating the balance of TH17 and Treg cells.

14.
Dalton Trans ; 48(43): 16184-16198, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31596294

RESUMO

Based on systematic DFT calculations, silaborane-based superhalogen anions, which obey the Wade-Mingos rule, are shown to be capable of giving rise to superacids via their combination with protons. Compared to previous carborane-based systems, the acidities of the composites here are stronger in both the gas phase and solution phase. Thus, the potential of candidates based on silaborane could be greater than those based on carborane in the search for ultra-strong acidic systems. Within a given group, a higher superhalogen anion vertical electron detachment energy (VDE) generally leads to stronger acidity. This consistency arises from the dominant role of the VDE, as established through the decomposition of the gas-phase acidity into different contributions. Thus, constructing superacids from superhalogens is a rational route whose future should be positive. Besides the VDE, other effects, i.e., the deformation energy (DE) and bond dissociation energy (BDE), could also be crucial, especially in terms of the differences between the acidities of composites belonging to different groups. A comparison between the results in the gas phase and solution phase indicates that complete calculations of both gas-phase ΔGacid and solution-phase pKa values are necessary to obtain an unbiased description of the acidity. The solvation free energies of the participants in the deprotonation process, especially the conjugate acid, are responsible for the discrepancies between gas phase and solution phase behavior.

15.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(3): 328-333, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31631598

RESUMO

Objective: To investigate the expression of miRNA-148b-3p and its target gene in the placenta between normal pregnant women and pregnant women with intrahepatic cholestasis of pregnancy (ICP) and to explore the possible mechanism of glucose metabolism of offspring with maternal cholestasis. Methods: There were 30 cases of normal pregnant women and 30 cases of pregnant women with ICP recruited in the study, all of whom underwent cesarean delivery from Mar. 2017 to Jan. 2018. Placenta tissues, maternal blood and cord blood were collected in each case. Maternal blood and cord blood were sent for biochemical detection. miRNA of placenta tissues was extracted and qRT-PCR was used to measure the expression of miR-148b-3p in the placenta. Normal HTR-8 cells were transfected with miR-148b-3p inhibitor/mimics wrapped with lipofectaine3000. qRT-PCR was used to measure the expression of miR-148b-3p, and Western blot was used to measure the expression of glucose transporter 1 (GLUT1) after transfection. Results: Maternal fasting blood glucose (FPG) and its fetal cord blood insulin levels in the ICP group were significantly higher than those of control. The expression of miR-148b-3p in the placenta of ICP group was lower than that of control group ( P<0.05). Compared with inhibitor control group, the expression of miR-148b-3p was decreased in HTR-8 cells transfected with miR-148b-3p inhibitor ( P<0.05), while the expression of GLUT1 was increased ( P<0.05). Compared with mimics control group, the expression of miR-148b-3p was increased in HTR-8 cells transfected with miR-148b-3p mimics ( P<0.05), while the expression of GLUT1 was decreased ( P<0.05). Conclusion: miR-148b-3p might participate in glucose metabolism of offspring with maternal cholestasis through the negative regulation of GLUT1 expression in placental trophoblast cells.


Assuntos
Colestase Intra-Hepática/genética , Transportador de Glucose Tipo 1/genética , Glucose/metabolismo , MicroRNAs/genética , Placenta/citologia , Complicações na Gravidez/genética , Trofoblastos/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Gravidez
16.
Int J Rheum Dis ; 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31621157

RESUMO

OBJECTIVE: Systemic sclerosis (SSc) is a rare debilitating autoimmune disease of the connective tissue. This study aimed to assess the recent prevalence and incidence of SSc across the world. METHODS: Using a systematic search strategy, PubMed/MEDLINE and EMBASE were searched to identify relevant studies published between 2006 and 2016. Two reviewers independently evaluated studies for inclusion based on inclusion/exclusion criteria and performed data extraction. The review was conducted and reported following the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. The pooled prevalence of SSc was calculated by meta-analysis using a random-effects model. RESULTS: There were 1364 references retrieved using the initial searching strategy, and 20 epidemiological publications were selected for data extraction. The identified studies reported prevalence ranging from 3.8 per 100 000 in Taiwan to 50 per 100 000 in the USA. The prevalence was 23 per 100 000 (95% CI: 16-29 per 100 000; 18 studies) in a pooled sample of 11 574 individuals. Incidence rate of SSc ranges from 0.77 per 100 000 person-years in the Netherlands to 5.6 per 100 000 person-years in the USA. SSc predominates in females with higher prevalence and incidence rates. It is important to note that different methodologies were used to derive these numbers so comparisons were made with caution. CONCLUSION: This review provides an assessment of the current estimates of disease prevalence and incidence of SSc. The epidemiological burdens of SSc vary among different regions of the world. The epidemiological data need to be interpreted with caution considering the methodological differences in deriving these estimates.

17.
Nat Commun ; 10(1): 4635, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604928

RESUMO

The filamentous bacteriophage fd bind a cell target with exquisite specificity through its few copies of display peptides, whereas nanoparticles functionalized with hundreds to thousands of synthetically generated phage display peptides exhibit variable and often-weak target binding. We hypothesise that some phage peptides in a hierarchical structure rather than in monomeric form recognise and bind their target. Here we show hierarchial forms of a brain-specific phage-derived peptide (herein as NanoLigand Carriers, NLCs) target cerebral endothelial cells through transferrin receptor and the receptor for advanced glycation-end products, cross the blood-brain-barrier and reach neurons and microglial cells. Through intravenous delivery of NLC-ß-secretase 1 (BACE1) siRNA complexes we show effective BACE1 down-regulation in the brain without toxicity and inflammation. Therefore, NLCs act as safe multifunctional nanocarriers, overcome efficacy and specificity limitations in active targeting with nanoparticles bearing phage display peptides or cell-penetrating peptides and expand the receptor repertoire of the display peptide.

18.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3509-3517, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621238

RESUMO

Rehmannia glutinosa, a perennial herbaceous species, belongs to the family Scrophularia-ceae. As a staple medicinal material, its tuberous roots are highly valued in traditional Chinese medicine. However, R. glutinosa suffers from serious consecutive monoculture problems in production, which leads to a decline in both productivity and quality. Phyllosphere bacteria, the most abundant component of phyllosphere microorganisms, play crucial roles in plant growth and health. Characterization of phyllosphere bacteria could provide new insights into the mechanisms of consecutive monoculture problems and their control measures. Meanwhile, the varied taxa could be served as an important indicator of consecutive monoculture problems. The barcoded pyrosequencing of 16S rDNA genes combined with a culture-dependent approach was applied to characterize the shifts of bacterial community structure and diversity in the phyllosphere under consecutive monoculture of R. glutinosa. The results showed that consecutive monoculture clearly affected bacterial community structure in the phyllosphere. The phyllosphere bacterial communities of the two-year monocultured (TY) and the diseased plants (DP) were more similar, and different from the one-year monocultured (OY). The evenness, Shannon and Simpson diversity indices were significantly lower in TY and DP than in OY. Species annotation showed that bacterial community in R. glutinosa phyllosphere mainly consisted of Proteobacteria (91.2%), Firmicutes (5.1%) and Actinobacteria (3.7%). There was no significant difference in the number of detected bacterial taxa. However, Proteobacteria was significantly increased while Firmicutes and Actinobacteria were significantly decreased under consecutive monoculture. At the genus level, the relative abundances of genera Exiguobacterium, Bacillus and Arthrobacter, potentially beneficial microorganisms, were significantly higher in OY than that in TY and DP, but it was opposite for the genus Pseudomonas. The results from the culture-dependent approach and pathogenicity test showed that Pseudomonas plecoglossicida D9, widely isolated from the diseased leaves, was highly pathogenic to leaves. In conclusion, R. glutinosa monoculture resulted in distinct phyllosphere bacterial community variation with the accumulation of pathogen loads at the expense of beneficial microorganisms, which could contribute to the occurrence of leaf disease symptoms,and aggravate R. glutinosa replant disease in a monoculture regime.


Assuntos
Rehmannia , Bactérias , DNA Ribossômico , Raízes de Plantas , Pseudomonas
19.
Artigo em Inglês | MEDLINE | ID: mdl-31660632

RESUMO

Hydrogen sulfide (H2 S) plays antidepressant-like roles in diabetic rats. However, the underlying mechanisms remain unclear. Brain-derived neurotropic factor (BDNF), a neurotrophic factor, plays important regulatory roles in depression by its high-affinity tropomysin-related kinase B (TrkB) receptor. Autophagy also is implicated in modulation of depression. Previous work confirmed the modulatory roles of H2 S in BDNF protein expression and autophagy. Thus, in this study, we explored whether the BDNF-TrkB pathway mediates the antidepressant-like effects of H2 S in diabetic rats and whether this process is achieved via promoting hippocampal autophagy. We demonstrated that H2 S upregulated the expressions of BDNF and p-TrkB proteins in the hippocampus of streptozotocin (STZ)-induced diabetic rats. K252a (an inhibitor of BDNF-TrkB pathway) reversed the antidepressant-like roles of H2 S, as evidenced by the tail suspension, forced swimming, novelty suppressed feeding, and elevated plus-maze tests. Furthermore, K252a abolished H2 S-promoted hippocampal autophagy in diabetic rats, as evidenced by a decrease in the number of autolysosome, downregulation of Beclin-1 (a regulator of autophagy in the early stage of the formation of autophagosomal membranes and its level is positively correlated with autophagic activity) expression, and upregulation of P62 (a substrate of autophagic degradation and its level is inversely correlated with autophagic activity) expression, in the hippocampus of rats co-treated with NaHS and STZ. Taken together, these data indicated that the BDNF-TrkB pathway mediates the antidepressant-like roles of H2 S in diabetic rats by enhancing hippocampal autophagy.

20.
J Hum Genet ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31636325

RESUMO

Primary ciliary dyskinesia (PCD) is a rare disorder that affects the biogenesis or function of motile cilia resulting in chronic airway disease. PCD is genetically and phenotypically heterogeneous, with causative mutations identified in over 40 genes; however, the genetic basis of many cases is unknown. Using whole-exome sequencing, we identified three affected siblings with clinical symptoms of PCD but normal ciliary structure, carrying compound heterozygous loss-of-function variants in CFAP221. Computational analysis suggests that these variants are the most damaging alleles shared by all three siblings. Nasal epithelial cells from one of the subjects demonstrated slightly reduced beat frequency (16.5 Hz vs 17.7 Hz, p = 0.16); however, waveform analysis revealed that the CFAP221 defective cilia beat in an aberrant circular pattern. These results show that genetic variants in CFAP221 cause PCD and that CFAP221 should be considered a candidate gene in cases where PCD is suspected but cilia structure and beat frequency appear normal.

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