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1.
Ann Oncol ; 33(12): 1318-1327, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36122798

RESUMO

BACKGROUND: Breast cancer has a significant heritable basis, of which ∼60% remains unexplained. Testing for BRCA1/BRCA2 offers useful discrimination of breast cancer risk within families, and identification of additional breast cancer susceptibility genes could offer clinical utility. PATIENTS AND METHODS: We included 2135 invasive breast cancer cases recruited via the Breast and Ovarian Cancer Susceptibility study, a retrospective UK study of familial breast cancer. ELIGIBILITY CRITERIA: female, BRCA-negative, white European ethnicity, and one of: (i) breast cancer family history, (ii) bilateral disease, (iii) young age of onset (<30 years), and (iv) concomitant ovarian cancer. We undertook exome sequencing of cases and carried out gene-level burden testing of rare damaging variants against those from 51 377 ethnicity-matched population controls from gnomAD. RESULTS: 159/2135 (7.4%) cases had a qualifying variant in an established breast cancer susceptibility gene, with minimal evidence of signal in other cancer susceptibility genes. Known breast cancer susceptibility genes PALB2, CHEK2, and ATM were the only genes to retain statistical significance after correcting for multiple testing. Due to the enrichment of hereditary cases in the series, we had good power (>80%) to detect a gene of BRCA1-like risk [odds ratio (OR) = 10.6] down to a population minor allele frequency of 4.6 × 10-5 (1 in 10 799, less than one-tenth that of BRCA1)and of PALB2-like risk (OR = 5.0) down to a population minor allele frequency of 2.8 × 10-4 (1 in 1779, less than half that of PALB2). Power was lower for identification of novel moderate penetrance genes (OR = 2-3) like CHEK2 and ATM. CONCLUSIONS: This is the largest case-control whole-exome analysis of enriched breast cancer published to date. Whilst additional breast cancer susceptibility genes likely exist, those of high penetrance are likely to be of very low mutational frequency. Contention exists regarding the clinical utility of such genes.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Adulto , Mutação em Linhagem Germinativa , Neoplasias da Mama/genética , Neoplasias da Mama/diagnóstico , Estudos Retrospectivos , Predisposição Genética para Doença , Neoplasias Ovarianas/genética
2.
Int Arch Occup Environ Health ; 93(5): 611-622, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31932956

RESUMO

PURPOSE: There is no review on the effect of work-related stressors on mental health of young workers. We systematically reviewed epidemiological evidence on this relationship. METHODS: The review searched eight databases: Embase, PubMed, Web of Science, Cinahl, Cochrane Library, Informit, PsycINFO, and Scopus from their respective start dates until May 2017. Studies that have examined a mental health outcome in relation to a work-related stressor as exposure in young workers were included. The review was reported based on the PRISMA statement. RESULTS: Three cross-sectional studies and six longitudinal cohort studies were included. Cross-sectional evidence showed that adverse work conditions including working overtime, job boredom, low skill variety, low autonomy, high job insecurity, and lack of reward were associated with poor mental health of young workers. Longitudinal evidence showed that high job demands, low job control, effort-reward imbalance, and low work support (men only) were associated with poor mental health. There was evidence on the contemporaneous relationship between two or more adverse work conditions and poor mental health. CONCLUSIONS: Although more research (particularly high-quality longitudinal studies) is warranted in this area, our review indicates that work-related stressors have a negative impact on the mental health of young workers. The current review suggests that workplace interventions and policy are required to improve the quality of work for young workers.


Assuntos
Transtornos Mentais/epidemiologia , Saúde Mental/estatística & dados numéricos , Estresse Ocupacional/psicologia , Adolescente , Feminino , Humanos , Masculino , Estresse Psicológico , Carga de Trabalho/estatística & dados numéricos , Adulto Jovem
3.
Health Promot Int ; 35(3): 478-485, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31081030

RESUMO

Males employed in the construction industry are at greater risk of suicide than other employed males. It is plausible that a high level of stigma against mental health problems explains the elevated rates of suicide among this group. This study sought to test the effectiveness of an electronic mental health stigma intervention on suicide ideation, communication about suicide and attempts. Participants were randomly assigned to receive either a series of brief contact interventions over a 6-week period or a wait list control. Suicidal ideation, communication about suicide and suicide attempts were assessed using the Suicidal Behaviors Questionnaire-Revised at post-intervention. We used linear regression to assess effectiveness at post-intervention, adjusting for relevant covariates using both conventional methods and a propensity score approach. Results indicate that the intervention had no significant impact on suicidal thoughts, communication or suicide attempts. There was some indication that individuals in the intervention group reported a slight increase in attempts and communication about suicide. These observations underscore an urgent need for more research to understand the complex and nuanced relationship between stigma and suicide in non-clinical populations.


Assuntos
Promoção da Saúde/métodos , Smartphone , Estigma Social , Prevenção do Suicídio , Adulto , Indústria da Construção , Humanos , Masculino , Pessoa de Meia-Idade , Ideação Suicida , Tentativa de Suicídio/prevenção & controle , Tentativa de Suicídio/psicologia , Inquéritos e Questionários , Vitória
4.
Eur J Cancer Care (Engl) ; 27(2): e12827, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29461652

RESUMO

Prostate cancer (PCa) poses a large health burden globally. Research indicates that men experience a range of psychological challenges associated with PCa including changes to identity, self-esteem and body image. The ways in which sexual orientation plays a role in the experience of PCa, and the subsequent impact on quality of life (QoL), body image and self-esteem have only recently been addressed. By addressing treatment modality, where participant numbers were sufficient, we also sought to explore whether gay (homosexual) men diagnosed with PCa (PCaDx) and with a primary treatment modality of surgery would report differences in body image and self-esteem compared with straight (heterosexual) men with PCaDx with a primary treatment modality of surgery, compared with gay and straight men without PCaDx. The results of our study identified overall differences with respect to PCaDx (related to urinary function, sexual function and health evaluation), and sexual orientation (related to self-esteem), rather than interactions between sexual orientation and PCaDx. Gay men with PCaDx exhibited higher levels of urinary functioning than straight men with PCaDx, the difference being reversed for gay and straight men without PCaDx; but this result narrowly failed to achieve statistical significance, suggesting a need for further research, with larger samples.


Assuntos
Imagem Corporal , Heterossexualidade/fisiologia , Homossexualidade Masculina/psicologia , Neoplasias da Próstata/psicologia , Autoimagem , Fatores Etários , Análise de Variância , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/terapia , Qualidade de Vida , Disfunções Sexuais Psicogênicas/psicologia , Transtornos Urinários/psicologia
5.
SSM Popul Health ; 4: 164-168, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29349285

RESUMO

BACKGROUND: High levels of self-stigma are associated with a range of adverse mental health, treatment, and functional outcomes. This prospective study examined the effects of an electronic mental health stigma reduction intervention on self-stigma (self-blame, shame, and help-seeking inhibition) among male construction workers in Australia. METHOD: Male construction workers (N = 682) were randomly assigned to receive either the intervention condition or the wait list control over a six-week period. Self-stigma was assessed using the Self-Stigma of Depression Scale at post-intervention. We conducted linear regression to assess the effectiveness of the intervention on self-stigma, adjusting for relevant covariates. RESULTS: Self-stigma was relatively low in the sample. The intervention had no significant effect on self-stigma, after adjusting for confounders. There were reductions in stigma in both the intervention and control groups at 6-week follow-up. Process evaluation indicated that participants generally enjoyed the program and felt that it was beneficial to their mental health. CONCLUSIONS: These observations underscore the need for further research to elucidate understanding of the experience of self-stigma among employed males.

6.
Biochim Biophys Acta Mol Basis Dis ; 1864(4 Pt B): 1293-1307, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28711597

RESUMO

Cholangiopathies encompass a heterogeneous group of disorders affecting biliary epithelial cells (i.e. cholangiocytes). Early diagnosis, prognosis and treatment still remain clinically challenging for most of these diseases and are critical for adequate patient care. In the past decade, extensive research has emphasized microRNAs (miRs) as potential non-invasive biomarkers and tools to accurately identify, predict and treat cholangiopathies. MiRs can be released extracellularly conjugated with lipoproteins or encapsulated in extracellular vesicles (EVs). Research on EVs is also gaining attention since they are present in multiple biological fluids and may represent a relevant source of novel non-invasive biomarkers and be vehicles for new therapeutic approaches. This review highlights the most promising candidate miRs and EV-related biomarkers in cholangiopathies, as well as their relevant roles in biliary pathophysiology. This article is part of a Special Issue entitled: Cholangiocytes in Health and Disease edited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen. RESEARCH STRATEGY: PubMed search (April 2017) was done with the following terms: "microRNA", "miRNA", "miR", "extracellular vesicles", "EV", "exosomes", "primary biliary cholangitis", "primary biliary cholangitis", "PBC", "primary sclerosing cholangitis", "PSC", "cholangiocarcinoma", "CCA", "biliary atresia", "BA", "polycystic liver diseases", "PLD", "cholangiopathies", "cholestatic liver disease". Most significant articles in full-text English were selected. The reference lists of selected papers were also considered.


Assuntos
Doenças dos Ductos Biliares/diagnóstico , Ductos Biliares/patologia , Células Epiteliais/patologia , Vesículas Extracelulares/metabolismo , MicroRNAs/metabolismo , Animais , Doenças dos Ductos Biliares/etiologia , Doenças dos Ductos Biliares/patologia , Ductos Biliares/citologia , Ductos Biliares/metabolismo , Biomarcadores/análise , Biomarcadores/metabolismo , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Perfilação da Expressão Gênica , Humanos , MicroRNAs/análise
7.
Andrology ; 5(5): 914-922, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28804972

RESUMO

Observational studies have suggested anthropometric traits, particularly increased height are associated with an elevated risk of testicular cancer (testicular germ cell tumour). However, there is an inconsistency between study findings, suggesting the possibility of the influence of confounding factors. To examine the association between anthropometric traits and testicular germ cell tumour using an unbiased approach, we performed a Mendelian randomisation study. We used genotype data from genome wide association studies of testicular germ cell tumour totalling 5518 cases and 19,055 controls. Externally weighted polygenic risk scores were created and used to evaluate associations with testicular germ cell tumour risk per one standard deviation (s.d) increase in genetically-defined adult height, adult BMI, adult waist hip ratio adjusted for BMI (WHRadjBMI), adult hip circumference adjusted for BMI (HIPadjBMI), adult waist circumference adjusted for BMI (WCadjBMI), birth weight (BW) and childhood obesity. Mendelian randomisation analysis did not demonstrate an association between any anthropometric trait and testicular germ cell tumour risk. In particular, despite good power, there was no global evidence for association between height and testicular germ cell tumour. However, three SNPs for adult height individually showed association with testicular germ cell tumour (rs4624820: OR = 1.47, 95% CI: 1.41-1.55, p = 2.7 × 10-57 ; rs12228415: OR = 1.17, 95% CI: 1.11-1.22, p = 3.1 × 10-10 ; rs7568069: OR = 1.13, 95% CI: 1.07-1.18, p = 1.1 × 10-6 ). This Mendelian randomisation analysis, based on the largest testicular germ cell tumour genome wide association dataset to date, does not support a causal etiological association between anthropometric traits and testicular germ cell tumour aetiology. Our findings are more compatible with confounding by shared environmental factors, possibly related to prenatal growth with exposure to these risk factors occurring in utero.


Assuntos
Estatura , Neoplasias Embrionárias de Células Germinativas , Neoplasias Testiculares , Adulto , Estatura/genética , Índice de Massa Corporal , Genótipo , Humanos , Masculino , Modelos Estatísticos , Neoplasias Embrionárias de Células Germinativas/genética , Polimorfismo de Nucleotídeo Único , Distribuição Aleatória , Fatores de Risco , Neoplasias Testiculares/genética , Relação Cintura-Quadril
9.
Semin Liver Dis ; 37(1): 45-55, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28201848

RESUMO

Polycystic liver diseases (PLDs) include a heterogeneous group of congenital disorders inherited as dominant or recessive genetic traits; they are manifested alone or in association with polycystic kidney disease. Ductal plate malformation during embryogenesis and the loss of heterozygosity linked to second-hit mutations may promote the dilatation and/or development of a large number (> 20) of biliary cysts, which are the main cause of morbidity in these patients. Surgical procedures aimed to eliminate symptomatic cysts show short-term beneficial effects, but are not able to block the disease progression. Therefore, liver transplantation is the only curative option. Intense studies on the molecular mechanisms involved in the pathogenesis of PLDs have resulted in different clinical trials, some of them with promising outcomes. Here the authors summarize the key aspects of PLD etiology, pathogenesis, and therapy, highlighting the most recent advances and future research directions.


Assuntos
Cistos , Hepatopatias , Cistos/genética , Cistos/patologia , Cistos/terapia , Progressão da Doença , Humanos , Hepatopatias/genética , Hepatopatias/patologia , Hepatopatias/terapia , Transplante de Fígado , Mutação , Fenótipo
10.
Int Rev Cell Mol Biol ; 327: 89-161, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27692181

RESUMO

Treatment of chronic pain has created a "silent epidemic," a term that describes the serious public health problem of the abuse of opioid painkillers and other prescription drugs. Conventional pharmacotherapy is limited by the loss of effectiveness in the long-term and by potentially lethal side effects. Efforts need to be focused on the development of nonpharmacological approaches. As significant progress is made in the viral vector technology, gene therapy involving recombinant viruses as vehicles may become a viable alternative for treatment of severe pain. Virus-based gene therapy has several advantages: (1) the transfer of a therapeutic gene to produce/release bioactive therapeutic molecules in a specific location in the nervous system thus minimizing the risks of off-target side effects, and (2) sustained long-term production of the therapeutic agent. This review compiles recently developed strategies for gene therapy targeting specific mechanisms of specific chronic pain conditions. A few successful studies on animal models of chronic pain have been translated to human clinical trials.


Assuntos
Dor Crônica/genética , Dor Crônica/terapia , Terapia Genética , Analgésicos Opioides/uso terapêutico , Animais , Dor Crônica/complicações , Dor Crônica/fisiopatologia , Humanos , Inflamação/complicações , Inflamação/patologia , Neuralgia/complicações , Neuralgia/genética , Neuralgia/fisiopatologia , Neuralgia/terapia , Nociceptividade
11.
Ann Oncol ; 27(3): 429-34, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26578737

RESUMO

BACKGROUND: We modelled the utility of applying a personalised screening approach for colorectal cancer (CRC) when compared with standard age-based screening. In this personalised screening approach, eligibility is determined by absolute risk which is calculated from age and polygenic risk score (PRS), where the PRS is relative risk attributable to common genetic variation. In contrast, eligibility in age-based screening is determined only by age. DESIGN: We calculated absolute risks of CRC from UK population age structure, incidence and mortality rate data, and a PRS distribution which we derived for the 37 known CRC susceptibility variants. We compared the number of CRC cases potentially detectable by personalised and age-based screening. Using Genome-Wide Complex Trait Analysis to calculate the heritability attributable to common variation, we repeated the analysis assuming all common CRC risk variants were known. RESULTS: Based on the known CRC variants, individuals with a PRS in the top 1% have a 2.9-fold increased CRC risk over the population median. Compared with age-based screening (aged 60: 10-year absolute risk 1.96% in men, 1.19% in women, as per the UK NHS National Bowel Screening Programme), personalised screening of individuals aged 55-69 at the same risk would lead to 16% fewer men and 17% fewer women being eligible for screening with 10% and 8%, respectively, fewer screen-detected cases. If all susceptibility variants were known, individuals with a PRS in the top 1% would have an estimated 7.7-fold increased risk. Personalised screening would then result in 26% fewer men and women being eligible for screening with 7% and 5% fewer screen-detected cases. CONCLUSION: Personalised screening using PRS has the potential to optimise population screening for CRC and to define those likely to maximally benefit from chemoprevention. There are however significant technical and operational details to be addressed before any such programme is introduced.


Assuntos
Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/métodos , Programas de Rastreamento/métodos , Medicina de Precisão/métodos , Idoso , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Fatores de Risco
13.
Bone Joint J ; 96-B(9): 1244-51, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25183598

RESUMO

The purpose of this study was to evaluate the long-term outcome of adults with spina bifida cystica (SBC) who had been treated either operatively or non-operatively for scoliosis during childhood. We reviewed 45 patients with a SBC scoliosis (Cobb angle ≥ 50º) who had been treated at one of two children's hospitals between 1991 and 2007. Of these, 34 (75.6%) had been treated operatively and 11 (24.4%) non-operatively. After a mean follow-up of 14.1 years (standard deviation (sd) 4.3) clinical, radiological and health-related quality of life (HRQOL) outcomes were evaluated using the Spina Bifida Spine Questionnaire (SBSQ) and the 36-Item Short Form Health Survey (SF-36). Although patients in the two groups were demographically similar, those who had undergone surgery had a larger mean Cobb angle (88.0º (sd 20.5; 50.0 to 122.0) ; : versus 65.7º (sd 22.0; 51.0 to 115.0); p < 0.01) and a larger mean clavicle-rib intersection difference (12.3 mm; (sd 8.5; 1 to 37); versus 4.1 mm, (sd 5.9; 0 to 16); p = 0.01) than those treated non-operatively. Both groups were statistically similar at follow-up with respect to walking capacity, neurological motor level, sitting balance and health-related quality of life (HRQOL) outcomes. Spinal fusion in SBC scoliosis corrects coronal deformity and stops progression of the curve but has no clear effect on HRQOL.


Assuntos
Escoliose/terapia , Espinha Bífida Cística/complicações , Fusão Vertebral , Adolescente , Adulto , Braquetes , Criança , Pré-Escolar , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Qualidade de Vida , Estudos Retrospectivos , Escoliose/etiologia , Escoliose/cirurgia , Inquéritos e Questionários , Resultado do Tratamento , Andadores , Adulto Jovem
14.
Nutr Cancer ; 66(4): 662-74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24660995

RESUMO

Our previous study had demonstrated that Astragalus saponins (AST) could reduce the side effects of orthodox chemotherapeutic drugs, while concurrently promote antitumor activity. In the present study, we attempted to investigate the potential synergistic anticarcinogenic effects of AST and a vinca alkaloid vinblastine (VBL). Reduced expression of key proangiogenic and metastatic factors including VEGF, bFGF, metalloproteinase (MMP)-2, and MMP-9 was detected in VBL-treated colon cancer cells, with further downregulation by combined VBL/AST treatment. Subsequently, VBL or AST decreased LoVo cell invasiveness, with further reduction when the drugs were cotreated. Significant growth inhibition and cell cycle arrest at G2/M phase were achieved by either drug treatment with apparent synergistic effects. VBL-induced apoptosis was confirmed but found to be unrelated to induction of the novel apoptotic protein NSAID-activated gene 1. In vivo study in tumor xenograft indicates that combined VBL/AST treatment resulted in sustained regression of tumor growth, with attenuation of the neutropenic and anemic effects of VBL. In addition, downregulation of proangiogenic and proliferative factors was also visualized, with boosting effect by combined drug treatment. These findings have provided evidence that AST combined with adjuvant chemotherapeutics like VBL could alleviate cancer development through diversified modes of action, including the regulation of angiogenesis.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Astrágalo/química , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Vimblastina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Regulação para Baixo , Sinergismo Farmacológico , Inativação Gênica , Células HCT116 , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Nus , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Electrocardiol ; 47(2): 158-65, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24411289

RESUMO

Mutations in transmembrane domains of the KCNQ1 subunit of the I(Ks) potassium channel have been associated with familial atrial fibrillation. We have investigated mechanisms by which the S1 domain S140G KCNQ1 mutation influences atrial arrhythmia risk and, additionally, whether it can affect ventricular electrophysiology. In perforated-patch recordings, S140G-KCNQ1+KCNE1 exhibited leftward-shifted activation, slowed deactivation and marked residual current. In human atrial action potential (AP) simulations, AP duration and refractoriness were shortened and rate-dependence flattened. Simulated I(Ks) but not I(Kr) block offset AP shortening produced by the mutation. In atrial tissue simulations, temporal vulnerability to re-entry was little affected by the S140G mutation. Spatial vulnerability was markedly increased, leading to more stable and stationary spiral wave re-entry in 2D stimulations, which was offset by I(Ks) block, and to scroll waves in 3D simulations. These changes account for vulnerability to AF with this mutation. Ventricular AP clamp experiments indicate a propensity for increased ventricular I(Ks) with the S140G KCNQ1 mutation and ventricular AP simulations showed model-dependent ventricular AP abbreviation.


Assuntos
Fibrilação Atrial/genética , Fibrilação Atrial/fisiopatologia , Canal de Potássio KCNQ1/genética , Mutação , Potenciais de Ação/fisiologia , Animais , Células CHO , Simulação por Computador , Cricetulus , Humanos , Técnicas de Patch-Clamp , Disfunção Ventricular/genética , Disfunção Ventricular/fisiopatologia
17.
J Appl Microbiol ; 114(3): 695-702, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23216653

RESUMO

AIMS: To investigate plasmid-mediated fosfomycin resistance related to fosA3 in Escherichia coli isolates collected from different animals in Hong Kong, China, 2008-2010. METHODS AND RESULTS: In total, 2106 faecal specimens from 210 cattle, 214 pigs, 460 chickens, 398 stray cats, 368 stray dogs and 456 wild rodents were cultured. The faecal colonization rates of fosfomycin-resistant E. coli were as follows: 11.2% in pigs, 8.6% in cattle, 7.3% in chickens, 2.4% in dogs, 0.8% in cats and 1.5% in rodents. The cultures yielded 1693 isolates of which 831 were extended-spectrum ß-lactamases (ESBL) producers. Fosfomycin-resistant isolates were more likely than fosfomycin-susceptible isolates to be producers of ESBL and to have resistance to chloramphenicol, ciprofloxacin, cotrimoxazole, gentamicin and tetracycline. Of the 101 fosfomycin-resistant isolates, 97 (96.0%) isolates were fosA3 positive and 94 (93.1%) were bla(CTX) (-M) positive. PCR mapping showed that the fosA3-containing regions were flanked by IS26, both upstream and downstream in 81 (83.5%) isolates, and by an upstream bla(CTX-M-14) -containing transposon-like structure (ΔISEcp1-bla(CTX-M-14) -ΔIS903 or ISEcp1-IS10 -bla(CTX-M-14) -ΔIS903) and a downstream IS26 in 14 (14.4%) isolates. For the remaining two isolates, fosA3 was flanked by a downstream IS26 but the upstream part cannot be defined. In a random subset of 18 isolates, fosA3 was carried on transferable plasmids with sizes of 50-200 kb and the following replicons: F2:A-B- (n = 3), F16:A1:B- (n = 2), F24:A-B- (n = 1), N (n = 1), B/O (n = 1) and untypeable (n = 3). SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates the emergence of fosA3-mediated fosfomycin resistance among multidrug-resistant E. coli isolates from various animals. IS26 transposon-like structures might be the main vehicles for dissemination of fosA3.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Fosfomicina/farmacologia , Animais , Gatos , Bovinos , Galinhas , Elementos de DNA Transponíveis , DNA Bacteriano/genética , Cães , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Fezes/microbiologia , Hong Kong , Gado , Testes de Sensibilidade Microbiana , Plasmídeos , Reação em Cadeia da Polimerase , Roedores , Suínos , beta-Lactamases/genética
18.
J Ethnopharmacol ; 141(2): 635-41, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21864667

RESUMO

AIM OF THE STUDY: We had reported that Astragalus saponins (AST) exert promising anti-tumorigenic effects by suppressing the growth of HT-29 human colon cancer cells and tumor xenograft. In the present study, we further investigated the anti-angiogenic property of AST in human gastric adenocarcinoma cells (AGS) and attempted to elucidate the underlying mechanism. MATERIALS AND METHODS: Viability of AGS cells was measured by using the MTT reduction method. Western blotting was performed to examine the effect of AST on apoptotic- and cell growth-related protein expression. Effect of AST on cell cycle progression was also evaluated using PI staining. A Matrigel invasion assay was then employed to demonstrate the effect of AST on the invasiveness of gastric cancer cells. The expression of invasion-associated proteins (VEGF and MMPs) was also investigated. RESULTS: AST could induce apoptosis in AGS cells by activating caspase 3 with subsequent cleavage of poly(ADP-ribose) polymerase. Besides, cell cycle arrest at the G2/M phase had been observed in AST-treated cells, leading to substantial growth inhibition. The anti-proliferative effect of AST was associated with the regulation of cyclin B1, p21 and c-myc. Results indicate that the number of AGS cells invaded through the Matrigel membrane was significantly reduced upon AST treatment, with concomitant down-regulation of the pro-angiogenic protein vascular endothelial growth factor (VEGF) as well as the metastatic proteins metalloproteinase (MMP)-2 and MMP-9. CONCLUSION: AST derived from the medicinal plant Astragalus membranaceus could modulate the invasiveness and angiogenesis of AGS cells besides its pro-apoptotic and anti-proliferative activities. These findings also suggest that AST has the potential to be further developed into an effective chemotherapeutic agent in treating advanced and metastatic gastric cancers.


Assuntos
Adenocarcinoma/patologia , Inibidores da Angiogênese/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Astrágalo , Movimento Celular/efeitos dos fármacos , Neovascularização Patológica/prevenção & controle , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Neoplasias Gástricas/patologia , Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/metabolismo , Inibidores da Angiogênese/isolamento & purificação , Proteínas Angiogênicas/metabolismo , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Astrágalo/química , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Invasividade Neoplásica , Neovascularização Patológica/metabolismo , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Saponinas/isolamento & purificação , Neoplasias Gástricas/irrigação sanguínea , Neoplasias Gástricas/metabolismo , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Water Sci Technol ; 62(5): 1129-35, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20818055

RESUMO

This research investigated the effects of co- and counter-current flow patterns on oil-water-solid separation efficiencies of a circular separator with inclined coalescence mediums. Oil-water-solid separations were tested at different influent concentrations and flowrates. Removal efficiencies increased as influent flowrate decreased, and their correlationship can be represented by power equations. These equations were used to predict the required flowrate, Q(ss50), for a given influent suspended solids concentration C(iss) to achieve the desired effluent suspended solids concentration, C(ess) of 50 mg/L, to meet environmental discharge requirements. The circular separator with counter-current flow was found to attend removal efficiencies relatively higher as compared to the co-current flow. As compared with co-current flow, counter-current flow Q(ss50) was approximately 1.65 times higher than co-current flow. It also recorded 13.16% higher oil removal at influent oil concentration, C(io) of 100 mg/L, and approximately 5.89% higher TSS removal at all influent flowrates. Counter-current flow's better removal performances were due to its higher coalescing area and constant interval between coalescence plate layers.


Assuntos
Óleos/química , Material Particulado/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Movimentos da Água
20.
Opt Express ; 18(10): 10055-67, 2010 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-20588859

RESUMO

We present Brillouin spectroscopy of YAG-derived optical fibers. It is found that the addition of yttria and alumina both tend to raise the acoustic velocity when added to silica, with the change due to yttria being much weaker. The temperature-dependence of the Stokes's shift in the YAG-derived fibers is also measured, disclosing a lesser temperature dependence than conventional Ge-doped fibers. These fibers are found experimentally to have a substantially larger acoustic attenuation coefficient relative to that of bulk silica, and assuming a photoelastic constant of amorphous YAG similar to that of pure crystalline YAG, a much-reduced Brillouin gain coefficient as a result. A 40 weight percent yttria and alumina fiber has a Brillouin gain coefficient estimated to be roughly one sixth of pure silica. We also show that the addition of Er to the YAG-derived system decreases the acoustic velocity and broadens the Brillouin spectrum.


Assuntos
Alumínio/química , Fibras Ópticas , Análise Espectral/instrumentação , Ítrio/química , Desenho de Equipamento , Análise de Falha de Equipamento
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