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1.
BMC Cancer ; 21(1): 37, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413214

RESUMO

BACKGROUND: Our previous studies demonstrated that the administration of crude Polysaccharide from Panax notoginseng (CPPN) can effectively prolong the lifespan of tumor-bearing mice via boosting the host immune system as well as weak cytotoxicity against hepatocellular carcinoma (HCC). In the present study, Neutral Polysaccharide (NPPN) were further purified from crude polysaccharide isolated from panax notoginseng. The effects of NPPN on the immune function and hematopoietic function of mice with low immunity and myelosuppression induced by cyclophosphamide (CTX) were investigated. The effect of NPPN combined with CTX on the tumor inhibition rate of the H22 tumor-bearing mice and the impact of NPPN on the proliferation of H22 liver cancer cells in vitro were investigated. METHODS: CPPN was obtained by water extraction and alcohol precipitation method, and further purified by DEAE Sepharose Fast Flow ion exchange resin column. NPPN was added to the immunosuppressed with myelosuppression mice induced by CTX. Thymus index, spleen index, lymphocyte proliferation stimulation index by adding of concanavalin A, determination of serum hemolysin, NK cell activity assay, mice carbon clearance experiment, blood count tests were detected. The tumor inhibition rate of the H22 tumor-bearing mice treated with NPPN combined with CTX was recorded. RESULTS: NPPN and 4 kinds of acid polysaccharide from Panax notoginseng (APPN) were successfully isolated from the CPPN by DEAE Sepharose Fast Flow ion exchange resin column. NPPN inhibited the growth of H22 cells and significantly increase the tumor inhibition rate of the H22 tumor-bearing mice combined with CTX. The elevation of the cellular and humoral immunity levels as well as a variety of blood count tests indicators of immunosuppressive with myelosuppression mice may contribute to the antitumor activity of NPPN. CONCLUSION: NPPN has a potential antitumor activity for the treatment of liver cancer combined with cyclophosphamide.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Ciclofosfamida/farmacologia , Sinergismo Farmacológico , Panax notoginseng/química , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Animais , Antineoplásicos Alquilantes/farmacologia , Apoptose , Carcinoma Hepatocelular/patologia , Proliferação de Células , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
2.
BMC Oral Health ; 21(1): 328, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210309

RESUMO

BACKGROUND: Dental fear is associated with the experience of prior dental treatment and avoidance of dental visits. It remains unclear if individuals show an intention of avoidance (IA) towards treatments that they have not received (i.e., non-experienced dental treatment). The study aims to investigated (a) if individuals showed an increased fear and IA to non-experienced, compared to experienced dental treatment, and (b) if fear and IA to non-experienced treatment is associated with dental anxiety. METHODS: Fear/IA of 12 common conditions of dental treatment of 402 adults were investigated. If subjects have experienced the condition, fear and IA were assessed based on subjects' prior experience (i.e., ExpFear/ExpIA). If they have not experienced the condition, fear and IA were assessed based on their anticipation (i.e., NExpFear/NExpIA). Trait dental anxiety was assessed using the Index of Dental Anxiety and Fear (IDAF-4C+). RESULTS: (A) NExpFear and NExpIA were significantly higher than ExpFear and ExpIA, respectively. (B) The IDAF-4C+ scores are positively correlated with NExpFear/NExpIA and negatively correlated with the magnification of fear (i.e., the discrepancy in the fear/IA of non-experienced vs. experienced conditions). (C) The condition 'extraction of a wisdom tooth' and 'root canal treatment' showed the highest ratings on NExpFear. CONCLUSIONS: Individuals may develop a high degree of fear and IA of the treatment they have not received. Trait dental anxiety plays a key role in the fear of non-experienced treatment.


Assuntos
Ansiedade ao Tratamento Odontológico , Intenção , Adulto , Assistência Odontológica , Medo , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
3.
BMC Oral Health ; 21(1): 647, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34920712

RESUMO

BACKGROUND: Dental anxiety is associated with negative experiences of dental treatment and dental-visiting behavior. The Modified Dental Anxiety Scale (MDAS) is widely used for assessing dental anxiety. The study aims to establish the psychometric properties of a Chinese version of the MDAS based on the Taiwan sample (i.e., T-MDAS). METHODS: The T-MDAS and dental-visiting behavior and experience were assessed for 402 adult subjects recruited from community and clinical sites. The following psychometric properties were assessed: (a) internal consistency, (b) temporal stability, (c) criterion-related validity (i.e., the association with the score of Index of Dental Anxiety and Fear, IDAF-4C), (d) discrimination validity (i.e., the difference in scores between the subjects with and without a habit of a regular dental visit, and (e) the construct validity from a confirmatory factor analysis (CFA). RESULTS: The T-MDAS showed good internal consistency (Cronbach's α = 0.88) and temporal stability (ρ = 0.69, p < 0.001). The score was significantly correlated with the score of the IDAF-4C (ρ = 0.76, p < 0.001) and differed between subjects who regularly visited a dentist or not, supporting good criterion-related validity and discrimination validity. Results from CFA supports good construct validity. Furthermore, higher dental anxiety was related to the lack of a regular dental visit, feeling pain during treatment, and feeling insufficient skills and empathy of dentists. A higher proportion of high-dental anxiety subjects in female subjects (8.5%), compared to male subjects (5.0%), was noted. CONCLUSIONS: The T-MDAS is a valid tool for assessing adult dental anxiety. The score is highly associated with dental-visiting behavior and experience of dental patients.


Assuntos
Ansiedade ao Tratamento Odontológico , Medo , Adulto , Ansiedade ao Tratamento Odontológico/diagnóstico , Feminino , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários , Taiwan
4.
Zhongguo Zhong Yao Za Zhi ; 46(19): 4898-4906, 2021 Oct.
Artigo em Zh | MEDLINE | ID: mdl-34738383

RESUMO

Bile of animal(mainly chicken, pig, snake, cow, and bear) has long been used as medicine. As the major active components of bile, bile acids mainly include cholic acid, deoxycholic acid, chenodeoxycholic acid, ursodeoxycholic acid, and taurochenodeoxycholic acid. They interact with intestinal microorganisms in enterohepatic circulation, thereby playing an important part in nutrient absorption and allocation, metabolism regulation, and dynamic balance. Bile acids have pharmacological effects such as protecting liver, kidney, heart, brain, and nerves, promoting bile secretion, dissolving gallstones, anti-cancer, relieving cough and dyspnea, dispelling phlegm, treating eye diseases, and regulating intestinal function and blood glucose, which are widely used in clinical practice. This study summarized and analyzed the research on the chemical constituents and pharmacological effects of bile acids from medicinal animals, in a bid to provide scientific basis and reference for the further development and utilization of bile acids.


Assuntos
Ácidos e Sais Biliares , Ácido Desoxicólico , Animais , Bovinos , Ácido Quenodesoxicólico , Ácidos Cólicos , Feminino , Suínos , Ácido Ursodesoxicólico
5.
Theor Appl Genet ; 132(1): 137-147, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30341491

RESUMO

KEY MESSAGE: A major QTL for downy mildew resistance was detected on chromosome 18 (Rpv27) in Vitis aestivalis-derived 'Norton' based on a high-resolution linkage map with SNP and SSR markers as well as 2 years of field and laboratory phenotyping data. Grapevine downy mildew caused by the oomycete Plasmopara viticola is one of the most widespread and destructive diseases, particularly in humid viticultural areas where it damages green tissues and defoliates vines. Traditional Vitis vinifera wine grape cultivars are susceptible to downy mildew whereas several North American and a few Asian cultivars possess various levels of resistance to this disease. To identify genetic determinants of downy mildew resistance in V. aestivalis-derived 'Norton,' a mapping population with 182 genotypes was developed from a cross between 'Norton' and V. vinifera 'Cabernet Sauvignon' from which a consensus map was constructed via 411 simple sequence repeat (SSR) markers. Using genotyping-by-sequencing, 3825 single nucleotide polymorphism (SNP) markers were also generated. Of these, 1665 SNP and 407 SSR markers were clustered into 19 linkage groups in 159 genotypes, spanning a genetic distance of 2203.5 cM. Disease progression in response to P. viticola was studied in this population for 2 years under both laboratory and field conditions, and strong correlations were observed among data sets (Spearman correlation coefficient = 0.57-0.79). A quantitative trait loci (QTL) analysis indicated a resistance locus on chromosome 18, here named Rpv27, explaining 33.8% of the total phenotypic variation. Flanking markers closely linked with the trait can be further used for marker-assisted selection in the development of new cultivars with resistance to downy mildew.


Assuntos
Mapeamento Cromossômico , Resistência à Doença/genética , Ligação Genética , Doenças das Plantas/genética , Vitis/genética , Cromossomos de Plantas/genética , Genótipo , Repetições de Microssatélites , Oomicetos/patogenicidade , Fenótipo , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Vitis/microbiologia
6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 48(6): 886-890, 2017 Nov.
Artigo em Zh | MEDLINE | ID: mdl-29260526

RESUMO

OBJECTIVE: To explore the association between intake of pickled vegetables and colorectal cancer (CRC),including the interactions between pickled vegetables and other dietary habits. METHODS: A 1:1 matched case-control study was undertaken,involving 400 patients with newly histopathologically diagnosed CRC and 400 healthy residents matched by age and gender. The participants were asked to complete a questionnaire. Conditional logistic regression models were established to identify risk factors of CRC and interactions between these factors. Additive interactions were analyzed using relative excess risk of interaction (RERI),attributable proportion of interaction (AP),and synergy index (S). RESULTS: Excessive intake of pickled vegetables (more than 3 times per week) increased the risk of CRC [odds ratio (OR)=2.703,95% confidence interval (CI): 1.866-3.916]. There was no multiplicative interaction between pickled vegetables and other dietary habits. Additive interactions were detected between pickled vegetables and cured meat,tea and bean products: with a RERI of 3.172 (95%CI: 0.834-5.518),2.131 (95%CI: 0.115-4.417) and 2.503 (95%CI: 0.760-4.246),respectively; an AP of 0.472 (95%CI: 0.245-0.699),0.386 (95%CI: 0.122-0.650) and 0.493 (95%CI: 0.253-0.732),respectively; and a S of 2.244 (95%CI: 1.266-3.978),1.893 (95%CI: 1.050-3.416) and 2.586 (95%CI:1.168-5.723) ,respectively. CONCLUSION: Excessive intake of pickled vegetables may be a risk factor of CRC. Cured meats and pickled vegetables might have a synergistic effect on CRC. However,tea and bean products might be antagonistic to the risk imposed by pickled vegetables on CRC.


Assuntos
Neoplasias Colorretais/epidemiologia , Dieta , Alimentos Fermentados , Verduras , Estudos de Casos e Controles , Humanos , Razão de Chances , Fatores de Risco
7.
Microbiology (Reading) ; 161(7): 1504-15, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25873583

RESUMO

Two-component signal transduction involves phosphoryl transfer between a histidine kinase sensor and a response regulator effector. The nitrate-responsive two-component signal transduction systems in Escherichia coli represent a paradigm for a cross-regulation network, in which the paralogous sensor-response regulator pairs, NarX-NarL and NarQ-NarP, exhibit both cognate (e.g. NarX-NarL) and non-cognate (e.g. NarQ-NarL) interactions to control output. Here, we describe results from bacterial adenylate cyclase two-hybrid (BACTH) analysis to examine sensor dimerization as well as interaction between sensor-response regulator cognate and non-cognate pairs. Although results from BACTH analysis indicated that the NarX and NarQ sensors interact with each other, results from intragenic complementation tests demonstrate that they do not form functional heterodimers. Additionally, intragenic complementation shows that both NarX and NarQ undergo intermolecular autophosphorylation, deviating from the previously reported correlation between DHp (dimerization and histidyl phosphotransfer) domain loop handedness and autophosphorylation mode. Results from BACTH analysis revealed robust interactions for the NarX-NarL, NarQ-NarL and NarQ-NarP pairs but a much weaker interaction for the NarX-NarP pair. This demonstrates that asymmetrical cross-regulation results from differential binding affinities between different sensor-regulator pairs. Finally, results indicate that the NarL effector (DNA-binding) domain inhibits NarX-NarL interaction. Missense substitutions at receiver domain residue Ser-80 enhanced NarX-NarL interaction, apparently by destabilizing the NarL receiver-effector domain interface.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/fisiologia , Redes Reguladoras de Genes , Transdução de Sinais , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Teste de Complementação Genética , Fosforilação , Ligação Proteica , Mapeamento de Interação de Proteínas , Multimerização Proteica , Processamento de Proteína Pós-Traducional , Técnicas do Sistema de Duplo-Híbrido
8.
Front Cardiovasc Med ; 9: 878566, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571216

RESUMO

Background: Whether women have a higher risk of adverse events compared with men following coronary angiography (CAG) and percutaneous coronary intervention (PCI) remains controversial. We aimed to investigate the sex differences in characteristics, treatments and outcomes among patients undergoing CAG and PCI in a large Chinese cohort. Methods: We analyzed patients undergoing CAG and/or PCI in this multi-center registry cohort study Cardiorenal ImprovemeNt II (CIN-II) in 5 Chinese tertiary hospitals from 2007 to 2020. Clinical characteristics, treatment (discharge medication and PCI) and in-hospital outcomes (mortality and major bleeding) were compared between women and men. Results: Totally 141,459 patients underwent CAG (44,362 [31.4%] women), of which 69,345 patients underwent PCI (15,376 [22.2%] women). Women were older (64.4 vs. 60.8 years), had more chronic comorbidities and lower PCI rate for stable coronary artery disease (CAD) than men (52.8 vs. 64.2%). Women received less CAG and PCI procedures. Among women undergoing PCI they received similar discharge medication treatment. In addition, women undergoing PCI had mildly lower rate of major bleeding (0.2 vs. 0.3%, P = 0.033) but higher in-hospital mortality (1.2 vs. 0.8%, P < 0.001). After adjustment, women had a higher risk in the major bleeding (adjusted odds ratio, 2.04 [95% CI: 1.07 to 3.62]), and the in-hospital mortality (adjusted odds ratio, 1.87 [95% CI: 1.36 to 2.56]). Conclusion: Among our Chinese cohort, women are older with more chronic comorbidities, receiving less PCI procedure and similar discharge medication treatment. Women have nearly 90% higher risk of in-hospital mortality and over 1-fold increased risk of major bleeding after PCI compared with men.

9.
Mol Microbiol ; 75(2): 394-412, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19968795

RESUMO

The NarX-NarL and NarQ-NarP sensor-response regulator pairs control Escherichia coli gene expression in response to nitrate and nitrite. Previous analysis suggests that the Nar two-component systems form a cross-regulation network in vivo. Here we report on the kinetics of phosphoryl transfer between different sensor-regulator combinations in vitro. NarX exhibited a noticeable kinetic preference for NarL over NarP, whereas NarQ exhibited a relatively slight kinetic preference for NarL. These findings were substantiated in reactions containing one sensor and both response regulators, or with two sensors and a single response regulator. We isolated 21 NarX mutants with missense substitutions in the cytoplasmic central and transmitter modules. These confer phenotypes that reflect defects in phospho-NarL dephosphorylation. Five of these mutants, all with substitutions in the transmitter DHp domain, also exhibited NarP-blind phenotypes. Phosphoryl transfer assays in vitro confirmed that these NarX mutants have defects in catalysing NarP phosphorylation. By contrast, the corresponding NarQ mutants conferred phenotypes indicating comparable interactions with both NarP and NarL. Our overall results reveal asymmetry in the Nar cross-regulation network, such that NarQ interacts similarly with both response regulators, whereas NarX interacts preferentially with NarL.


Assuntos
Proteínas de Ligação a DNA/genética , Escherichia coli K12/genética , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Proteínas de Membrana/genética , Fosfoproteínas/genética , Proteínas Quinases/genética , Substituição de Aminoácidos , Escherichia coli K12/fisiologia , Homeostase/genética , Cinética , Fenótipo , Fosforilação , Fosfotransferases/genética , Fosfotransferases/metabolismo
10.
J Bacteriol ; 192(3): 734-45, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19966007

RESUMO

In the nitrate-responsive, homodimeric NarX sensor, two cytoplasmic membrane alpha-helices delimit the periplasmic ligand-binding domain. The HAMP domain, a four-helix parallel coiled-coil built from two alpha-helices (HD1 and HD2), immediately follows the second transmembrane helix. Previous computational studies identified a likely coiled-coil-forming alpha-helix, the signaling helix (S helix), in a range of signaling proteins, including eucaryal receptor guanylyl cyclases, but its function remains obscure. In NarX, the HAMP HD2 and S-helix regions overlap and apparently form a continuous coiled-coil marked by a heptad repeat stutter discontinuity at the distal boundary of HD2. Similar composite HD2-S-helix elements are present in other sensors, such as Sln1p from Saccharomyces cerevisiae. We constructed deletions and missense substitutions in the NarX S helix. Most caused constitutive signaling phenotypes. However, strongly impaired induction phenotypes were conferred by heptad deletions within the S-helix conserved core and also by deletions that remove the heptad stutter. The latter observation illuminates a key element of the dynamic bundle hypothesis for signaling across the heptad stutter adjacent to the HAMP domain in methyl-accepting chemotaxis proteins (Q. Zhou, P. Ames, and J. S. Parkinson, Mol. Microbiol. 73:801-814, 2009). Sequence comparisons identified other examples of heptad stutters between a HAMP domain and a contiguous coiled-coil-like heptad repeat sequence in conventional sensors, such as CpxA, EnvZ, PhoQ, and QseC; other S-helix-containing sensors, such as BarA and TorS; and the Neurospora crassa Nik-1 (Os-1) sensor that contains a tandem array of alternating HAMP and HAMP-like elements. Therefore, stutter elements may be broadly important for HAMP function.


Assuntos
Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/fisiologia , Proteínas Quinases/química , Proteínas Quinases/fisiologia , Sequência de Aminoácidos , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/fisiologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Proteínas de Escherichia coli/genética , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Dados de Sequência Molecular , Complexos Multienzimáticos/química , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/fisiologia , Mutagênese Sítio-Dirigida , Fenótipo , Fosfotransferases/química , Fosfotransferases/genética , Fosfotransferases/fisiologia , Proteínas Quinases/genética , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína/genética , Estrutura Terciária de Proteína/fisiologia , Homologia de Sequência de Aminoácidos , Transdução de Sinais , Relação Estrutura-Atividade
11.
Zhonghua Gan Zang Bing Za Zhi ; 18(3): 194-8, 2010 Mar.
Artigo em Zh | MEDLINE | ID: mdl-20380796

RESUMO

OBJECTIVE: To investigate the expression of nuclear factor kappa B (NF-kB), transforming growth factor beta1 (TGFbeta1), fibronectin (FN) in liver from diabetic rats. METHODS: Twenty male Sprague-Dawley rats were divided randomly into two groups: normal control group (n = 10) and type 2 diabetic group (n = 10). After 4 weeks of high-fat feeding, diabetic group rats were injected with low dosage streptozotocin (30 mg/kg) intraperitoneally to induce type 2 diabetic rat models. The diabetic rats received high-fat feeding for another 12 weeks. At the end of the experiment, the fibrosis lesion was observed under light microscopy after Masson staining. The mRNA levels of NF-kB, TGFbeta1, FN from rats liver were assayed by semi-quantity RT-PCR, the protein levels of NF-kB, TGFbeta1, FN was detected by IHC. RESULTS: Fibrosis was found in diabetic rats. The levels of TGFbeta1, FN mRNA in liver tissues increased in diabetic rats compared with normal control rats (0.91+/-0.19 vs 0.47+/-0.20, t = 5.233, P less than 0.05; 1.85+/-0.70 vs 1.22+/-0.39, t = 2.463, P less than 0.05). And the protein levels of NF-kB P65, TGFbeta1, FN in liver tissues from diabetic rats were significantly higher than those in normal control rats (10978.77+/-8782.59 vs 4206.86+/-1430.56, Z = 1.979, P less than 0.05; 8551.00+/-4768.68 vs 4036.85+/-1051.12, Z = 2.303, P less than 0.05; 16980.30+/-11529.29 vs 5701.95+/-9461.75, t = -2.391, P less than 0.05). CONCLUSION: Upregulation of NF-kB, TGFbeta1, FN in liver tissues may play a role in the hepatic fibrogenesis in diabetic rats.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Fibronectinas/metabolismo , Cirrose Hepática/metabolismo , NF-kappa B/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/patologia , Fígado/patologia , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Masculino , Ratos , Ratos Sprague-Dawley
12.
Influenza Other Respir Viruses ; 14(2): 210-214, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31856341

RESUMO

We measured antibodies against H7N9 virus 2 years after infection in 14 patients who were infected during October 2016-September 2017. Approximately 2 years after infection, antibody titers ≥10 were detectable in 13 (92.9%) patients. Three (21.4%) of 14 patients had hemagglutination inhibition titers ≥40, and their geometric mean titer (GMT) was 20 (95% CI 15.7-28.1), whereas 10 (71.4%) and all 14 (100%) of the 14 patients had titers ≥40, and GMTs at 34.4 (95% CI 25.7-51.2) and 73.45 (54.7-106.7) for neuraminidase inhibition and microneutralization antibodies, respectively. Our findings suggest that H7N9 infection may induce long-term antibody response at least 2 years after infection.


Assuntos
Anticorpos Antivirais/imunologia , Formação de Anticorpos , Subtipo H7N9 do Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Adulto , Idoso , Feminino , Seguimentos , Testes de Inibição da Hemaglutinação , Humanos , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade
13.
Transbound Emerg Dis ; 67(5): 2118-2125, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32248624

RESUMO

Avian influenza A(H5N6) keeps evolving, causing outbreaks in birds and sporadic infections in human. Here, we report a fatal paediatric infection caused by a novel reassortant H5N6 virus. The patient was an obese 9-year-old girl. She initiated with fever and cough, then developed pneumonia, acute respiratory distress syndrome (ARDS) and respiratory failure. Lower respiratory tract aspirates and anal swabs were serially taken till the patient's death. Viral isolation, genome sequencing and phylogenetic analysis were conducted. A novel reassortant H5N6 virus was isolated from the patient. Except the PA gene, all other 7 genes of the virus belonged to H5N6 genotype A (S4-like virus). The PA gene was probably obtained from Eurasian waterfowl influenza viruses. The H5N6 virus was consistently detected from the patient's respiratory samples till the 17th day after symptom onset, but not from anal swabs or urine sample by real-time reverse transcription polymerase chain reaction (RT-PCR). Significantly elevated (32-fold) serum antibodies to H5N6 virus were observed during the patient's course of disease. Aside from the identified novel reassortant H5N6 viral strain, obesity, delayed confirmation of aetiology and specific antiviral treatment, and prolonged virus shedding could have contributed to the poor clinical outcome.

14.
J Bacteriol ; 191(3): 1006-17, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19060149

RESUMO

The enterobacterium Klebsiella oxytoca uses a variety of inorganic and organic nitrogen sources, including purines, nitrogen-rich compounds that are widespread in the biosphere. We have identified a 23-gene cluster that encodes the enzymes for utilizing purines as the sole nitrogen source. Growth and complementation tests with insertion mutants, combined with sequence comparisons, reveal functions for the products of these genes. Here, we report our characterization of 12 genes, one encoding guanine deaminase and the others encoding enzymes for converting (hypo)xanthine to allantoate. Conventionally, xanthine dehydrogenase, a broadly distributed molybdoflavoenzyme, catalyzes sequential hydroxylation reactions to convert hypoxanthine via xanthine to urate. Our results show that these reactions in K. oxytoca are catalyzed by a two-component oxygenase (HpxE-HpxD enzyme) homologous to Rieske nonheme iron aromatic-ring-hydroxylating systems, such as phthalate dioxygenase. Our results also reveal previously undescribed enzymes involved in urate oxidation to allantoin, catalyzed by a flavoprotein monooxygenase (HpxO enzyme), and in allantoin conversion to allantoate, which involves allantoin racemase (HpxA enzyme). The pathway also includes the recently described PuuE allantoinase (HpxB enzyme). The HpxE-HpxD and HpxO enzymes were discovered independently by de la Riva et al. (L. de la Riva, J. Badia, J. Aguilar, R. A. Bender, and L. Baldoma, J. Bacteriol. 190:7892-7903, 2008). Thus, several enzymes in this K. oxytoca purine utilization pathway differ from those in other microorganisms. Isofunctional homologs of these enzymes apparently are encoded by other species, including Acinetobacter, Burkholderia, Pseudomonas, Saccharomyces, and Xanthomonas.


Assuntos
Proteínas de Bactérias/metabolismo , Klebsiella oxytoca/metabolismo , Purinas/metabolismo , Proteínas de Bactérias/genética , Dioxigenases/genética , Dioxigenases/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Guanina/química , Guanina/metabolismo , Guanina Desaminase/genética , Guanina Desaminase/metabolismo , Klebsiella oxytoca/enzimologia , Klebsiella oxytoca/genética , Modelos Genéticos , Dados de Sequência Molecular , Estrutura Molecular , Racemases e Epimerases/genética , Racemases e Epimerases/metabolismo , Análise de Sequência de DNA , Transcrição Gênica , Ureia/análogos & derivados , Ureia/química , Ureia/metabolismo , Ácido Úrico/química , Ácido Úrico/metabolismo , Xantina/química , Xantina/metabolismo , Xantina Desidrogenase/genética , Xantina Desidrogenase/metabolismo
15.
J Bacteriol ; 191(3): 996-1005, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19060147

RESUMO

Escherichia coli, a facultative aerobe, expresses two distinct respiratory nitrate reductases. The periplasmic NapABC enzyme likely functions during growth in nitrate-limited environments, whereas the membrane-bound NarGHI enzyme functions during growth in nitrate-rich environments. Maximal expression of the napFDAGHBC operon encoding periplasmic nitrate reductase results from synergistic transcription activation by the Fnr and phospho-NarP proteins, acting in response to anaerobiosis and nitrate or nitrite, respectively. Here, we report that, during anaerobic growth with no added nitrate, less-preferred carbon sources stimulated napF operon expression by as much as fourfold relative to glucose. Deletion analysis identified a cyclic AMP receptor protein (Crp) binding site upstream of the NarP and Fnr sites as being required for this stimulation. The napD and nrfA operon control regions from Shewanella spp. also have apparent Crp and Fnr sites, and expression from the Shewanella oneidensis nrfA control region cloned in E. coli was subject to catabolite repression. In contrast, the carbon source had relatively little effect on expression of the narGHJI operon encoding membrane-bound nitrate reductase under any growth condition tested. Carbon source oxidation state had no influence on synthesis of either nitrate reductase. The results suggest that the Fnr and Crp proteins may act synergistically to enhance NapABC synthesis during growth with poor carbon sources to help obtain energy from low levels of nitrate.


Assuntos
Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Óperon/genética , Sequência de Bases , Sítios de Ligação , Carbono/farmacologia , AMP Cíclico/farmacologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Proteínas Ferro-Enxofre/genética , Proteínas Ferro-Enxofre/metabolismo , Dados de Sequência Molecular , Nitrato Redutase/metabolismo , Nitratos/farmacologia , Receptores de AMP Cíclico/genética , Receptores de AMP Cíclico/metabolismo
16.
J Bacteriol ; 190(11): 3869-76, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18375557

RESUMO

NarX-NarL and NarQ-NarP are paralogous two-component regulatory systems that control Escherichia coli gene expression in response to the respiratory oxidants nitrate and nitrite. Nitrate stimulates the autophosphorylation rates of the NarX and NarQ sensors, which then phosphorylate the response regulators NarL and NarP to activate and repress target operon transcription. Here, we investigated both the autophosphorylation and dephosphorylation of soluble sensors in which the maltose binding protein (MBP) has replaced the amino-terminal transmembrane sensory domain. The apparent affinities (K(m)) for ADP were similar for both proteins, about 2 microM, whereas the affinity of MBP-NarQ for ATP was lower, about 23 microM. At a saturating concentration of ATP, the rate constant of MBP-NarX autophosphorylation (about 0.5 x 10(-4) s(-1)) was lower than that observed for MBP-NarQ (about 2.2 x 10(-4) s(-1)). At a saturating concentration of ADP, the rate constant of dephosphorylation was higher than that of autophosphorylation, about 0.03 s(-1) for MBP-NarX and about 0.01 s(-1) for MBP-NarQ. For other studied sensors, the published affinities for ADP range from about 16 microM (KinA) to about 40 microM (NtrB). This suggests that only a small proportion of NarX and NarQ remain phosphorylated in the absence of nitrate, resulting in efficient response regulator dephosphorylation by the remaining unphosphorylated sensors.


Assuntos
Escherichia coli K12/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de Membrana/metabolismo , Nitratos/farmacologia , Fosfoproteínas/metabolismo , Proteínas Quinases/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Escherichia coli K12/efeitos dos fármacos , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/fisiologia , Cinética , Proteínas de Membrana/genética , Fosfoproteínas/genética , Fosforilação , Proteínas Quinases/genética , Fatores de Tempo
18.
J Neurol ; 254(4): 501-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17401518

RESUMO

BACKGROUND: Recently, transcranial color-coded sonography (TCCS) has been found to have a diagnostic value in patients with idiopathic Parkinson's disease (IPD), which displays increased hyperechogenicity at the substantia nigra (SN). OBJECTIVE: To use TCCS, to assess the difference in SN hyperechogenicity and intracranial hemodynamics among subjects with IPD, vascular parkinsonism (VP) and controls. METHODS: Eighty IPD and 30 VP patients, and 60 controls were recruited into this study. The hyperechogenicity area at the SN and midbrain were calculated by encircling the outer circumference from the ipsilateral temporal window, using TCCS in each subject. The hemodynamics of intracranial large arteries, including flow velocity and pulsatility index (PI), were also measured. RESULTS: The presence of SN hyperechogenicity was significantly higher in the IPD patients than in the VP patients and controls (84% vs. 20% & 5%, respectively, p < 0.001). In IPD patients, the SN hyperechogenicity was correlated with the neurological severity and disease duration. Twenty-five (66.7%) VP patients had obvious vascular abnormality, as seen in TCCS study. The mean PI was significantly more elevated in the VP patients than those in the IPD patients and controls (all p < 0.05), but there was no significant difference of flow velocities among the VP, IPD patients and controls. CONCLUSION: TCCS, combining B-mode imaging for SN echogenicity and trancranial Doppler for intracranial hemodynamics, is a useful diagnostic tool in the differentiation between IPD and VP. These findings also suggest that multiple subcortical vascular lesions may damage the basal ganglia and thalamocortical circuit and result in parkinsonism features in VP patients.


Assuntos
Doença de Parkinson Secundária/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana/métodos , Idoso , Circulação Cerebrovascular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Doença de Parkinson Secundária/fisiopatologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Substância Negra/diagnóstico por imagem
19.
Medicine (Baltimore) ; 96(10): e6259, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28272231

RESUMO

The potential value of N-terminal pro-brain natriuretic peptide (NT-proBNP) for contrast-induced acute kidney injury (CI-AKI) in patients with heart failure and mid-range ejection fraction (HFmrEF) is unclear. We investigated whether NT-proBNP is associated with CI-AKI and long-term mortality following elective cardiac catheterization in patients with HFmrEF.A total of 174 consecutive patients with HFmrEF undergoing elective coronary angiography or intervention were enrolled. The primary endpoint was the development of CI-AKI, defined as an absolute increase of ≥0.3 mg/dL or ≥ 50% from baseline serum creatinine with 48 hours after contrast medium exposure. Receiver-operating characteristic curve analysis was conducted, and Youden index was used to determine the best cutoff NT-proBNP value. Multivariable logistic regression and Cox proportional hazards regression analyses were performed to identify the independent risk factors for CI-AKI and long-term mortality, respectively.The incidence of CI-AKI was 12.1%. Patients with CI-AKI had higher NT-proBNP values than those without (4373[1561.9-7470.5] vs 1303[625.2-2482.3], P = 0.003). Receiver-operating characteristic curve revealed that NT-proBNP was not significantly different from the Mehran risk score in predicting CI-AKI (area under the curve [AUC] = 0.723 vs 0.767, P = 0.516). The best cutoff NT-proBNP value for CI-AKI was 3299 pg/mL, with 70.6% sensitivity and 83.1% specificity. Multivariable analysis demonstrated that NT-proBNP ≥3299 pg/mL is significantly related to CI-AKI (odds ratio = 12.79; 95% confidence interval, 3.18-51.49; P < 0.001). Cox regression analysis showed that NT-proBNP ≥3299 pg/mL is associated with long-term mortality (adjusted hazard ratio = 11.91; 95%CI, 2.16-65.70; P = 0.004) during follow-up.In patients with HFmrEF, NT-proBNP ≥3299 pg/mL is associated with CI-AKI and long-term mortality following elective coronary angiography or intervention.


Assuntos
Injúria Renal Aguda/sangue , Injúria Renal Aguda/induzido quimicamente , Insuficiência Cardíaca/complicações , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Injúria Renal Aguda/mortalidade , Idoso , Cateterismo Cardíaco , China/epidemiologia , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Volume Sistólico
20.
Oncotarget ; 8(65): 109762-109771, 2017 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-29312646

RESUMO

OBJECTIVE: To investigate the predictive value of post-procedural early (within 24 h) increase in cystatin C for contrast-induced acute kidney injury (CI-AKI) and all-cause mortality following coronary angiography or intervention. METHODS: We prospectively investigated 1042 consecutive patients with both baseline and early post-procedural cystatin C measurement undergoing coronary angiography or intervention. CI-AKI was defined as an increase ≥0.3 mg/dL or >50% in serum creatinine from baseline within 48 h post-procedure. Mean follow-up was 2.26 years. RESULTS: Overall, the patients had a CI-AKI incidence was 3.6% (38/1042), mean serum creatinine of 87 µmol/L. Compared with Mehran risk score, post-procedural early absolute increase (AUC: 0.584 vs. 0.706, P = 0.060) and relative increase (AUC: 0.585 vs. 0.706, P = 0.058) in cystatin C had poorer predictive value for CI-AKI. According to multivariate analysis, post-procedural significant early increase (≥0.3 mg/dL or ≥10%) in cystatin C developed in 231 patients (22.2%), was not independent predictor of CI-AKI (adjusted OR: 1.23, 95% CI, 0.56-2.69, P = 0.612), and long-term mortality (adjusted HR: 0.90; P = 0.838). CONCLUSIONS: Our data suggested post-procedural early increase (within 24 h) in cystatin C was not effective for predicting CI-AKI or all-cause mortality following coronary angiography or intervention among patients at relative low risk of CI-AKI, the negative finding of poor predictive value should be further evaluated in larger multicenter trials.

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