Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
Gastroenterology ; 166(1): 44-58, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37734419

RESUMEN

The gut microbiota plays a significant role in the pathogenesis of both forms of inflammatory bowel disease (IBD), namely, Crohn's disease (CD) and ulcerative colitis (UC). Although evidence suggests dysbiosis and loss of beneficial microbial species can exacerbate IBD, many new studies have identified microbes with pathogenic qualities, termed "pathobionts," within the intestines of patients with IBD. The concept of pathobionts initiating or driving the chronicity of IBD has largely focused on the putative aggravating role that adherent invasive Escherichia coli may play in CD. However, recent studies have identified additional bacterial and fungal pathobionts in patients with CD and UC. This review will highlight the characteristics of these pathobionts and their implications for IBD treatment. Beyond exploring the origins of pathobionts, we discuss those associated with specific clinical features and the potential mechanisms involved, such as creeping fat (Clostridium innocuum) and impaired wound healing (Debaryomyces hansenii) in patients with CD as well as the increased fecal proteolytic activity (Bacteroides vulgatus) seen as a biomarker for UC severity. Finally, we examine the potential impact of pathobionts on current IBD therapies, and several new approaches to target pathobionts currently in the early stages of development. Despite recognizing that pathobionts likely contribute to the pathogenesis of IBD, more work is needed to define their modes of action. Determining whether causal relationships exist between pathobionts and specific disease characteristics could pave the way for improved care for patients, particularly for those not responding to current IBD therapies.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , Humanos , Enfermedades Inflamatorias del Intestino/terapia , Enfermedades Inflamatorias del Intestino/microbiología , Colitis Ulcerosa/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico , Intestinos , Heces
2.
J Biol Chem ; 299(1): 102729, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36410439

RESUMEN

Fibroblast growth factor receptor 1 (FGFR1) is a receptor tyrosine kinase that plays a major role in developmental processes and metabolism. The dysregulation of FGFR1 through genetic aberrations leads to skeletal and metabolic diseases as well as cancer. For this reason, FGFR1 is a promising therapeutic target, yet a very challenging one due to potential on-target toxicity. More puzzling is that both agonistic and antagonistic FGFR1 antibodies are reported to exhibit similar toxicity profiles in vivo, namely weight loss. In this study, we aimed to assess and compare the mechanism of action of these molecules to better understand this apparent contradiction. By systematically comparing the binding of these antibodies and the activation or the inhibition of the major FGFR1 signaling events, we demonstrated that the molecules displayed similar properties and can behave either as an agonist or antagonist depending on the presence or the absence of the endogenous ligand. We further demonstrated that these findings translated in xenografts mice models. In addition, using time-resolved FRET and mass spectrometry analysis, we showed a functionally distinct FGFR1 active conformation in the presence of an antibody that preferentially activates the FGFR substrate 2 (FRS2)-dependent signaling pathway, demonstrating that modulating the geometry of a FGFR1 dimer can effectively change the signaling outputs and ultimately the activity of the molecule in preclinical studies. Altogether, our results highlighted how bivalent antibodies can exhibit both agonistic and antagonistic activities and have implications for targeting other receptor tyrosine kinases with antibodies.


Asunto(s)
Anticuerpos Monoclonales , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos , Transducción de Señal , Animales , Humanos , Ratones , Neoplasias , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/agonistas , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/antagonistas & inhibidores , Anticuerpos Monoclonales/farmacología
3.
J Infect Dis ; 225(7): 1266-1273, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33974708

RESUMEN

BACKGROUND: No studies have explored the association between pneumococcal nasopharyngeal density and severe pneumonia using the World Health Organization (WHO) 2013 definition. In Lao People's Democratic Republic (Lao PDR), we determine the association between nasopharyngeal pneumococcal density and severe pneumonia in children. METHODS: A prospective observational study was undertaken at Mahosot Hospital, Vientiane, from 2014 to mid-2018. Children <5 years admitted with acute respiratory infections (ARIs) were included. Clinical and demographic data were collected alongside nasopharyngeal swabs for pneumococcal quantification by lytA real-time quantitative polymerase chain reaction. Severe pneumonia was defined using the 2013 WHO definition. For pneumococcal carriers, a logistic regression model examined the association between pneumococcal density and severe pneumonia, after adjusting for potential confounders including demographic and household factors, 13-valent pneumococcal conjugate vaccine status, respiratory syncytial virus co-detection, and preadmission antibiotics. RESULTS: Of 1268 participants with ARI, 32.3% (n = 410) had severe pneumonia and 36.9% (n = 468) had pneumococcal carriage. For pneumococcal carriers, pneumococcal density was positively associated with severe pneumonia (adjusted odds ratio, 1.4 [95% confidence interval, 1.1-1.8]; P = .020). CONCLUSIONS: Among children with ARIs and pneumococcal carriage, pneumococcal carriage density was positively associated with severe pneumonia in Lao PDR. Further studies may determine if pneumococcal density is a useful marker for pneumococcal conjugate vaccine impact on childhood pneumonia.


Asunto(s)
Infecciones Neumocócicas , Neumonía , Portador Sano/epidemiología , Niño , Preescolar , Estudios Transversales , Humanos , Lactante , Laos/epidemiología , Nasofaringe , Vacunas Neumococicas , Neumonía/epidemiología , Serogrupo
4.
PLoS Med ; 18(8): e1003733, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34343186

RESUMEN

BACKGROUND: There is limited empiric evidence on the coverage of pneumococcal conjugate vaccines (PCVs) required to generate substantial indirect protection. We investigate the association between population PCV coverage and indirect protection against invasive pneumococcal disease (IPD) and pneumonia hospitalisations among undervaccinated Australian children. METHODS AND FINDINGS: Birth and vaccination records, IPD notifications, and hospitalisations were individually linked for children aged <5 years, born between 2001 and 2012 in 2 Australian states (New South Wales and Western Australia; 1.37 million children). Using Poisson regression models, we examined the association between PCV coverage, in small geographical units, and the incidence of (1) 7-valent PCV (PCV7)-type IPD; (2) all-cause pneumonia; and (3) pneumococcal and lobar pneumonia hospitalisation in undervaccinated children. Undervaccinated children received <2 doses of PCV at <12 months of age and no doses at ≥12 months of age. Potential confounding variables were selected for adjustment a priori with the assistance of a directed acyclic graph. There were strong inverse associations between PCV coverage and the incidence of PCV7-type IPD (adjusted incidence rate ratio [aIRR] 0.967, 95% confidence interval [CI] 0.958 to 0.975, p-value < 0.001), and pneumonia hospitalisations (all-cause pneumonia: aIRR 0.991 95% CI 0.990 to 0.994, p-value < 0.001) among undervaccinated children. Subgroup analyses for children <4 months old, urban, rural, and Indigenous populations showed similar trends, although effects were smaller for rural and Indigenous populations. Approximately 50% coverage of PCV7 among children <5 years of age was estimated to prevent up to 72.5% (95% CI 51.6 to 84.4) of PCV7-type IPD among undervaccinated children, while 90% coverage was estimated to prevent 95.2% (95% CI 89.4 to 97.8). The main limitations of this study include the potential for differential loss to follow-up, geographical misclassification of children (based on residential address at birth only), and unmeasured confounders. CONCLUSIONS: In this study, we observed substantial indirect protection at lower levels of PCV coverage than previously described-challenging assumptions that high levels of PCV coverage (i.e., greater than 90%) are required. Understanding the association between PCV coverage and indirect protection is a priority since the control of vaccine-type pneumococcal disease is a prerequisite for reducing the number of PCV doses (from 3 to 2). Reduced dose schedules have the potential to substantially reduce program costs while maintaining vaccine impact.


Asunto(s)
Hospitalización/estadística & datos numéricos , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/administración & dosificación , Neumonía/epidemiología , Cobertura de Vacunación/estadística & datos numéricos , Australia , Relación Dosis-Respuesta a Droga , Vacunas Conjugadas/administración & dosificación
5.
J Viral Hepat ; 28(2): 260-267, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33065774

RESUMEN

BACKGROUND: Current literature indicates that direct-acting antivirals (DAAs) are cost-effective to treat compensated cirrhotic patients with hepatitis C. Although already funded by public payers, it is unknown whether it is economical to reimburse DAAs within the more advanced decompensated cirrhosis population. METHODS: A state-transition model was developed to conduct a cost-utility analysis of sofosbuvir-velpatasvir (SOF/VEL) plus ribavirin regimen for 12 weeks. The evaluated cohort had a mean age of 58 years and Child-Turcotte-Pugh (CTP) class B cirrhosis with decompensated symptoms. A scenario analysis was performed on CTP C patients. We used a payer perspective, a lifetime time horizon and a 1.5% annual discount rate. RESULTS: While SOF/VEL plus ribavirin treatment for 12 weeks increased costs by $156 676, it provided an extra 4.00 quality-adjusted life years (QALYs) compared to best supportive care (no DAA therapy). With an incremental cost-effectiveness ratio of $39 169 per QALY, SOF/VEL plus ribavirin was determined to be cost-effective at a willingness to pay of $50 000 per QALY. SOF/VEL reduced liver-related deaths and reduced progression to CTP C cirrhosis by 20.4% and 21.9%, respectively. On the contrary, SOF/VEL regimen resulted in increases in liver transplants and hepatocellular carcinoma (HCC) by 54.0% and 42.5%, respectively. Similar results were found for CTP C patients. CONCLUSION: This analysis informs payers that SOF/VEL should continue to be reimbursed in decompensated hepatitis C patients. It also supports the recommendations by the American Association for the Study of Liver Diseases to continue screening for HCC in decompensated cirrhotic patients who have achieved sustained virologic response.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis C Crónica , Neoplasias Hepáticas , Antivirales/uso terapéutico , Carbamatos , Carcinoma Hepatocelular/tratamiento farmacológico , Análisis Costo-Beneficio , Genotipo , Hepacivirus , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Compuestos Heterocíclicos de 4 o más Anillos , Humanos , Recién Nacido , Cirrosis Hepática/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Ribavirina/uso terapéutico , Sofosbuvir/uso terapéutico , Resultado del Tratamiento
6.
Bull World Health Organ ; 97(6): 386-393, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31210676

RESUMEN

OBJECTIVE: To quantify the impact of the change in definition of severe pneumonia on documented pneumonia burden. METHODS: We reviewed existing data acquired during observational hospitalized pneumonia studies, before the introduction of the pneumococcal conjugate vaccine, in infants aged 2-23 months from Fiji, Gambia, Lao People's Democratic Republic, Malawi, Mongolia and Viet Nam. We used clinical data to calculate the percentage of all-cause pneumonia hospitalizations with severe pneumonia, and with primary end-point consolidation, according to both the 2005 or 2013 World Health Organization (WHO) definitions. Where population data were available, we also calculated the incidence of severe pneumonia hospitalizations according to the different definitions. FINDINGS: At six of the seven sites, the percentages of all-cause pneumonia hospitalizations due to severe pneumonia were significantly less (P < 0.001) according to the 2013 WHO definition compared with the 2005 definition. However, the percentage of severe pneumonia hospitalizations, according to the two definitions of severe pneumonia, with primary end-point consolidation varied little within each site. The annual incidences of severe pneumonia hospitalizations per 100 000 infants were significantly less (all P < 0.001) according to the 2013 definition compared with the 2005 definition, ranging from a difference of -301.0 (95% confidence interval, CI: -405.2 to -196.8) in Fiji to -3242.6 (95% CI: -3695.2 to -2789.9) in the Gambia. CONCLUSION: The revision of WHO's definition of severe pneumonia affects pneumonia epidemiology, and hence the interpretation of any pneumonia intervention impact evaluation.


Asunto(s)
Neumonía/diagnóstico , Neumonía/epidemiología , Femenino , Fiji/epidemiología , Gambia/epidemiología , Hospitalización , Humanos , Incidencia , Lactante , Laos/epidemiología , Malaui/epidemiología , Masculino , Mongolia/epidemiología , Índice de Severidad de la Enfermedad , Vietnam/epidemiología , Organización Mundial de la Salud
7.
Nature ; 501(7466): 232-6, 2013 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-23934108

RESUMEN

KRAS and BRAF activating mutations drive tumorigenesis through constitutive activation of the MAPK pathway. As these tumours represent an area of high unmet medical need, multiple allosteric MEK inhibitors, which inhibit MAPK signalling in both genotypes, are being tested in clinical trials. Impressive single-agent activity in BRAF-mutant melanoma has been observed; however, efficacy has been far less robust in KRAS-mutant disease. Here we show that, owing to distinct mechanisms regulating MEK activation in KRAS- versus BRAF-driven tumours, different mechanisms of inhibition are required for optimal antitumour activity in each genotype. Structural and functional analysis illustrates that MEK inhibitors with superior efficacy in KRAS-driven tumours (GDC-0623 and G-573, the former currently in phase I clinical trials) form a strong hydrogen-bond interaction with S212 in MEK that is critical for blocking MEK feedback phosphorylation by wild-type RAF. Conversely, potent inhibition of active, phosphorylated MEK is required for strong inhibition of the MAPK pathway in BRAF-mutant tumours, resulting in superior efficacy in this genotype with GDC-0973 (also known as cobimetinib), a MEK inhibitor currently in phase III clinical trials. Our study highlights that differences in the activation state of MEK in KRAS-mutant tumours versus BRAF-mutant tumours can be exploited through the design of inhibitors that uniquely target these distinct activation states of MEK. These inhibitors are currently being evaluated in clinical trials to determine whether improvements in therapeutic index within KRAS versus BRAF preclinical models translate to improved clinical responses in patients.


Asunto(s)
Genes ras/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Neoplasias/enzimología , Neoplasias/genética , Proteína Oncogénica p21(ras)/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/metabolismo , Regulación Alostérica/efectos de los fármacos , Azetidinas/farmacología , Supervivencia Celular/efectos de los fármacos , Ensayos Clínicos como Asunto , Cristalografía por Rayos X , Activación Enzimática/efectos de los fármacos , Retroalimentación Fisiológica/efectos de los fármacos , Células HCT116 , Humanos , Imidazoles/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Quinasas de Proteína Quinasa Activadas por Mitógenos/química , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Modelos Moleculares , Neoplasias/patología , Niacinamida/análogos & derivados , Niacinamida/farmacología , Fosforilación/efectos de los fármacos , Fosfoserina/metabolismo , Piperidinas/farmacología , Proteínas Proto-Oncogénicas B-raf/genética
8.
J Biol Chem ; 292(35): 14311-14324, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28655764

RESUMEN

The interconnected PI3K and MAPK signaling pathways are commonly perturbed in cancer. Dual inhibition of these pathways by the small-molecule PI3K inhibitor pictilisib (GDC-0941) and the MEK inhibitor cobimetinib (GDC-0973) suppresses cell proliferation and induces cell death better than either single agent in several preclinical models. Using mass spectrometry-based phosphoproteomics, we have identified the RING finger E3 ubiquitin ligase RNF157 as a target at the intersection of PI3K and MAPK signaling. We demonstrate that RNF157 phosphorylation downstream of the PI3K and MAPK pathways influences the ubiquitination and stability of RNF157 during the cell cycle in an anaphase-promoting complex/cyclosome-CDH1-dependent manner. Deletion of these phosphorylation-targeted residues on RNF157 disrupts binding to CDH1 and protects RNF157 from ubiquitination and degradation. Expression of the cyclin-dependent kinase 2 (CDK2), itself a downstream target of PI3K/MAPK signaling, leads to increased phosphorylation of RNF157 on the same residues modulated by PI3K and MAPK signaling. Inhibition of PI3K and MEK in combination or of CDK2 by their respective small-molecule inhibitors reduces RNF157 phosphorylation at these residues and attenuates RNF157 interaction with CDH1 and its subsequent degradation. Knockdown of endogenous RNF157 in melanoma cells leads to late S phase and G2/M arrest and induces apoptosis, the latter further potentiated by concurrent PI3K/MEK inhibition, consistent with a role for RNF157 in the cell cycle. We propose that RNF157 serves as a novel node integrating oncogenic signaling pathways with the cell cycle machinery and promoting optimal cell cycle progression in transformed cells.


Asunto(s)
Apoptosis , Sistema de Señalización de MAP Quinasas , Melanoma/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo , Procesamiento Proteico-Postraduccional , Transducción de Señal , Ubiquitina-Proteína Ligasas/metabolismo , Sustitución de Aminoácidos , Antígenos CD , Apoptosis/efectos de los fármacos , Cadherinas/antagonistas & inhibidores , Cadherinas/genética , Cadherinas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Quinasa 2 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 2 Dependiente de la Ciclina/genética , Quinasa 2 Dependiente de la Ciclina/metabolismo , Inhibidores Enzimáticos/farmacología , Estabilidad de Enzimas/efectos de los fármacos , Eliminación de Gen , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Melanoma/tratamiento farmacológico , Melanoma/enzimología , Melanoma/patología , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosforilación/efectos de los fármacos , Mutación Puntual , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Interferencia de ARN , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Fase S/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Ubiquitina-Proteína Ligasas/antagonistas & inhibidores , Ubiquitina-Proteína Ligasas/química , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación/efectos de los fármacos
9.
J Paediatr Child Health ; 54(4): 356-364, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29322575

RESUMEN

AIM: To identify and describe potentially vaccine-preventable child deaths in New South Wales (NSW). METHODS: Child deaths in NSW from 2005 to 2014 potentially preventable by vaccination were identified from the NSW Child Death Register (maintained by the NSW Ombudsman) and the Notifiable Conditions Information Management System (NSW Health). Medical and post-mortem records were reviewed. Cases were classified as vaccine-preventable based on the strength of evidence for the relevant infection causing death and likelihood that death was preventable through vaccination. A two-source capture-recapture method was used to estimate the true number of deaths. Age-specific mortality rate and number of deaths by disease, area of residence and comorbidity were analysed. Deaths were classified as preventable based on vaccine availability, eligibility under the National Immunisation Program, age and presence of any contraindications. RESULTS: Fifty-four deaths were identified as definitely or probably due to diseases for which a vaccine was available, with a total average annual mortality rate of 0.33 per 100 000 children and 2.1 per 100 000 infants. Two thirds of deaths occurred in children with no identified comorbidities. Twenty-three deaths were classified as preventable or potentially preventable by vaccination, with influenza (12 deaths) and meningococcal disease (five deaths) most common. An additional 15 deaths would be potentially preventable as of August 2016 due to immunisation recommendation changes including maternal vaccination. CONCLUSION: Maternal vaccination along with increased uptake of childhood influenza vaccination could reduce child deaths, particularly from influenza.


Asunto(s)
Causas de Muerte , Prevención Primaria , Vacunación , Adolescente , Niño , Preescolar , Femenino , Humanos , Programas de Inmunización , Lactante , Gripe Humana/mortalidad , Masculino , Infecciones Meningocócicas/mortalidad , Nueva Gales del Sur/epidemiología , Prevención Primaria/métodos , Tos Ferina/mortalidad
10.
BMC Public Health ; 17(1): 113, 2017 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-28118827

RESUMEN

BACKGROUND: Amidst an Ebola virus disease (EVD) epidemic of unprecedented magnitude in west Africa, concerns about the risk of importing EVD led to the introduction of programs for the screening and monitoring of travellers in a number of countries, including Australia. Emerging reports indicate that these programs are feasible to implement, however rigorous evaluations are not yet available. We aimed to evaluate the program of screening and monitoring travellers in New South Wales. METHODS: We conducted a mixed methods study to evaluate the program of screening and monitoring travellers in New South Wales. We extracted quantitative data from the Notifiable Conditions Information Management System database and obtained qualitative data from two separate surveys of public health staff and arrivals, conducted by phone. RESULTS: Between 1 October 2014 and 13 April 2015, public health staff assessed a total of 122 out of 123 travellers. Six people (5%) developed symptoms compatible with EVD and required further assessment. None developed EVD. Aid workers required lower levels of support compared to other travellers. Many travellers experienced stigmatisation. Public health staff were successful in supporting travellers to recognise and manage symptoms. CONCLUSION: We recommend that programs for monitoring travellers should be tailored to the needs of different populations and include specific strategies to remediate stigmatisation.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Brotes de Enfermedades/prevención & control , Fiebre Hemorrágica Ebola/psicología , Vigilancia en Salud Pública/métodos , Viaje/psicología , Fiebre Hemorrágica Ebola/prevención & control , Humanos , Nueva Gales del Sur , Investigación Cualitativa , Estigma Social , Encuestas y Cuestionarios
11.
Proc Natl Acad Sci U S A ; 110(48): 19426-31, 2013 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-24218548

RESUMEN

Targeted therapeutics that block signal transduction through the RAS-RAF-MEK and PI3K-AKT-mTOR pathways offer significant promise for the treatment of human malignancies. Dual inhibition of MAP/ERK kinase (MEK) and phosphatidylinositol 3-kinase (PI3K) with the potent and selective small-molecule inhibitors GDC-0973 and GDC-0941 has been shown to trigger tumor cell death in preclinical models. Here we have used phosphomotif antibodies and mass spectrometry (MS) to investigate the effects of MEK/PI3K dual inhibition during the period immediately preceding cell death. Upon treatment, melanoma cell lines responded by dramatically increasing phosphorylation on proteins containing a canonical DNA damage-response (DDR) motif, as defined by a phosphorylated serine or threonine residue adjacent to glutamine, [s/t]Q. In total, >2,000 [s/t]Q phosphorylation sites on >850 proteins were identified by LC-MS/MS, including an extensive network of DDR proteins. Linear mixed-effects modeling revealed 101 proteins in which [s/t]Q phosphorylation was altered significantly in response to GDC-0973/GDC-0941. Among the most dramatic changes, we observed rapid and sustained phosphorylation of sites within the ABCDE cluster of DNA-dependent protein kinase. Preincubation of cells with the inhibitors of the DDR kinases DNA-dependent protein kinase or ataxia-telangiectasia mutated enhanced GDC-0973/GDC-0941-mediated cell death. Network analysis revealed specific enrichment of proteins involved in RNA metabolism along with canonical DDR proteins and suggested a prominent role for this pathway in the response to MEK/PI3K dual inhibition.


Asunto(s)
Daño del ADN/fisiología , Melanoma/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosfoproteínas/metabolismo , Azetidinas/farmacología , Western Blotting , Línea Celular Tumoral , Cromatografía Liquida , Humanos , Indazoles/farmacología , Modelos Lineales , Fosforilación/efectos de los fármacos , Piperidinas/farmacología , Proteómica/métodos , Transducción de Señal , Sulfonamidas/farmacología , Espectrometría de Masas en Tándem/métodos
12.
Genome Res ; 22(12): 2315-27, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23033341

RESUMEN

Lung cancer is a highly heterogeneous disease in terms of both underlying genetic lesions and response to therapeutic treatments. We performed deep whole-genome sequencing and transcriptome sequencing on 19 lung cancer cell lines and three lung tumor/normal pairs. Overall, our data show that cell line models exhibit similar mutation spectra to human tumor samples. Smoker and never-smoker cancer samples exhibit distinguishable patterns of mutations. A number of epigenetic regulators, including KDM6A, ASH1L, SMARCA4, and ATAD2, are frequently altered by mutations or copy number changes. A systematic survey of splice-site mutations identified 106 splice site mutations associated with cancer specific aberrant splicing, including mutations in several known cancer-related genes. RAC1b, an isoform of the RAC1 GTPase that includes one additional exon, was found to be preferentially up-regulated in lung cancer. We further show that its expression is significantly associated with sensitivity to a MAP2K (MEK) inhibitor PD-0325901. Taken together, these data present a comprehensive genomic landscape of a large number of lung cancer samples and further demonstrate that cancer-specific alternative splicing is a widespread phenomenon that has potential utility as therapeutic biomarkers. The detailed characterizations of the lung cancer cell lines also provide genomic context to the vast amount of experimental data gathered for these lines over the decades, and represent highly valuable resources for cancer biology.


Asunto(s)
Empalme Alternativo , Regulación Neoplásica de la Expresión Génica , Genoma Humano/genética , Neoplasias Pulmonares/genética , Mutación , Transcriptoma , ATPasas Asociadas con Actividades Celulares Diversas , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Línea Celular Tumoral , Variaciones en el Número de Copia de ADN , ADN Helicasas/genética , ADN Helicasas/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Epigenómica , Exones , Marcadores Genéticos , Heterocigoto , Histona Demetilasas/genética , Histona Demetilasas/metabolismo , N-Metiltransferasa de Histona-Lisina , Humanos , Cariotipificación/métodos , Neoplasias Pulmonares/patología , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Polimorfismo de Nucleótido Simple , Reproducibilidad de los Resultados , Análisis de Secuencia de ARN , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Regulación hacia Arriba , Proteína de Unión al GTP rac1/genética , Proteína de Unión al GTP rac1/metabolismo
13.
Commun Dis Intell Q Rep ; 39(1): E19-26, 2015 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-26063094

RESUMEN

INTRODUCTION: Since the introduction of universal rubella vaccination in 1989, the incidence of rubella and congenital rubella syndrome (CRS) in Australia has declined significantly. Worldwide, there has been a focus on elimination, with the region of the Americas declaring rubella elimination in 2011. This study aims to review Australian rubella epidemiology for the 2008-2012 period, in the context of historical and international trends. METHODS: Notification, hospitalisation and mortality data were sourced from the National Notifiable Diseases Surveillance System, the National Hospital Morbidity Database and the Australian Bureau of Statistics (ABS). Data analysis focused on 2008-2012 for notifications and 2008-2011 for hospitalisations and deaths. ABS population data were used to calculate rates. RESULTS: The average annual rubella notification rate in Australia from 2008-2012 was 0.18 per 100,000 and the average annual hospitalisation rate was 0.03 per 100,000 from 2008-2011. One case of CRS was notified in 2012 and 1 hospitalisation with a principal diagnosis of CRS was recorded in 2008. The median age of rubella notifications was 29 years and 37% of notifications were for infections acquired overseas. DISCUSSION: Rubella continues to be well controlled in Australia and CRS is rare. The low incidence and increasing proportion of imported cases and other evidence suggest that elimination has been achieved; however, for formal verification of rubella elimination the expansion of genotypic surveillance will be required. Ongoing rubella control needs to focus on improved surveillance, maintenance of high levels of vaccine coverage, vaccination of at-risk populations in Australia, and regional and global efforts towards rubella elimination.


Asunto(s)
Erradicación de la Enfermedad/estadística & datos numéricos , Vacuna contra el Sarampión-Parotiditis-Rubéola/administración & dosificación , Virus de la Rubéola/inmunología , Rubéola (Sarampión Alemán)/epidemiología , Rubéola (Sarampión Alemán)/prevención & control , Vacunación , Adolescente , Adulto , Australia/epidemiología , Niño , Preescolar , Notificación de Enfermedades/estadística & datos numéricos , Monitoreo Epidemiológico , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Esquemas de Inmunización , Incidencia , Lactante , Masculino , Persona de Mediana Edad , Rubéola (Sarampión Alemán)/inmunología
14.
Mol Pharm ; 11(11): 4199-207, 2014 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-25243894

RESUMEN

Cobimetinib is a MEK inhibitor currently in clinical trials as an anticancer agent. The objectives of this study were to determine in vitro and in vivo if cobimetinib is a substrate of P-glycoprotein (P-gp) and/or breast cancer resistance protein (Bcrp1) and to assess the implications of efflux on cobimetinib pharmacokinetics (PK), brain penetration, and target modulation. Cell lines transfected with P-gp or Bcrp1 established that cobimetinib was a substrate of P-gp but not a substrate of Bcrp1. In vivo, after intravenous and oral administration of cobimetinib to FVB (wild-type; WT), Mdr1a/b(-/-), Bcrp1 (-/-), and Mdr1a/b(-/-)/Bcrp(-/-) knockout (KO) mice, clearance was similar in WT (35.5 ± 16.7 mL/min/kg) and KO animals (22.0 ± 3.6 to 27.6 ± 5.2 mL/min/kg); oral exposure was also similar between WT and KO animals. After an oral 10 mg/kg dose of cobimetinib, the mean total brain to plasma ratio (Kp) at 6 h postdose was 0.3 and 0.2 in WT and Bcrp1(-/-) mice, respectively. In Mdr1a/b(-/-) and Mdr1a/1b/Bcrp1(-/-) KO mice and WT mice treated with elacridar (a P-gp and BCRP inhibitor), Kp increased to 11, 6, and 7, respectively. Increased brain exposure in Mdr1a/b(-/-) and Mdr1a/1b/Bcrp1(-/-) KO and elacridar treated mice was accompanied by up to ∼65% suppression of the target (pErk) in brain tissue, compared to WT mice. By MALDI imaging, the cobimetinib signal intensity was relatively high and was dispersed throughout the brain of Mdr1a/1b/Bcrp1(-/-) KO mice compared to low/undetectable signal intensity in WT mice. The efflux of cobimetinib by P-gp may have implications for the treatment of patients with brain tumors/metastases.


Asunto(s)
Subfamilia B de Transportador de Casetes de Unión a ATP/fisiología , Transportadoras de Casetes de Unión a ATP/fisiología , Azetidinas/farmacocinética , Barrera Hematoencefálica/efectos de los fármacos , Encéfalo/metabolismo , MAP Quinasa Quinasa 1/antagonistas & inhibidores , Piperidinas/farmacocinética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Animales , Azetidinas/farmacología , Transporte Biológico , Encéfalo/efectos de los fármacos , Cromatografía Liquida , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Femenino , Ratones , Ratones Noqueados , Piperidinas/farmacología , Espectrometría de Masas en Tándem , Distribución Tisular , Miembro 4 de la Subfamilia B de Casete de Unión a ATP
15.
Drug Alcohol Rev ; 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38972045

RESUMEN

Mandatory drug testing is commonly used in Australian prisons to detect and deter drug use. In this commentary, we review the limited evidence for mandatory drug testing programs, highlight potential harms associated with their implementation and provide recommendations for drug surveillance in prisons concordant with a harm minimisation framework.

16.
Drug Alcohol Rev ; 43(3): 775-786, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38147397

RESUMEN

INTRODUCTION: Children in families affected by substance use disorders are at high risk of being placed in out-of-home care (OOHC). We aimed to describe the characteristics of parents who inject drugs and identify correlates associated with child placement in OOHC. METHODS: We used baseline data from a community-based cohort of parents who inject drugs (SuperMIX) from Melbourne, Australia. Participants were recruited via convenience, respondent-driven and snowball sampling from April 2008 to November 2020, with follow-up until March 2021. To explore correlates associated with child placement to OOHC, we used multivariable logistic regression and assessed for potential interactions between gender and a range of relevant covariates. RESULTS: Of the 1067 participants, 611 (57%) reported being parents. Fifty-six percent of parents reported child protection involvement. Almost half (49%) had children in OOHC. Nearly half of the parents lived in unstable accommodation (44%) and many of them experienced moderate-severe levels of anxiety (48%) and depression (53%). Female or non-binary gender, identifying as Aboriginal or Torres Strait Islander, experiencing assault and having more children were associated with child removal to OOHC. Of the 563 participants who reported their own childhood care status, 135 (24%) reported they had been removed to OOHC. DISCUSSION AND CONCLUSIONS: We identified high rates of child placement in OOHC among parents who inject drugs. There is a need for targeted health and social services, that are gender and culturally responsive, in addition to systems-level interventions addressing social inequities, such as housing, to support parents to care for their children.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Padres , Niño , Femenino , Humanos , Ansiedad , Trastornos de Ansiedad , Demografía
17.
Lancet Reg Health West Pac ; 45: 101052, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38699291

RESUMEN

Background: Pneumonia is the leading cause of death in young children globally and is prevalent in the Papua New Guinea highlands. We investigated clinical predictors of hypoxic pneumonia to inform local treatment guidelines in this resource-limited setting. Methods: Between 2013 and 2020, two consecutive prospective observational studies were undertaken enrolling children 0-4 years presenting with pneumonia to health-care facilities in Goroka Town, Eastern Highlands Province. Logistic regression models were developed to identify clinical predictors of hypoxic pneumonia (oxygen saturation <90% on presentation). Model performance was compared against established criteria to identify severe pneumonia. Findings: There were 2067 cases of pneumonia; hypoxaemia was detected in 36.1%. The strongest independent predictors of hypoxic pneumonia were central cyanosis on examination (adjusted odds ratio [aOR] 5.14; 95% CI 3.47-7.60), reduced breath sounds (aOR 2.92; 95% CI 2.30-3.71), and nasal flaring or grunting (aOR 2.34; 95% CI 1.62-3.38). While the model developed to predict hypoxic pneumonia outperformed established pneumonia severity criteria, it was not sensitive enough to be clinically useful at this time. Interpretation: Given signs and symptoms are unable to accurately detect hypoxia, all health care facilities should be equipped with pulse oximeters. However, for the health care worker without access to pulse oximetry, consideration of central cyanosis, reduced breath sounds, nasal flaring or grunting, age-specific tachycardia, wheezing, parent-reported drowsiness, or bronchial breathing as suggestive of hypoxaemic pneumonia, and thus severe disease, may prove useful in guiding management, hospital referral and use of oxygen therapy. Funding: Funded by Pfizer Global and the Bill & Melinda Gates Foundation.

18.
Gut Microbes ; 16(1): 2413372, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39428744

RESUMEN

The host restricts Salmonella enterica serovar Typhimurium infection of the gut via inflammasome-dependent sloughing of infected epithelial cells. Here we determined that concurrent caspase 1/11-dependent release of the goblet cell-derived mucin, Muc2, into the intestinal lumen also controls Salmonella burdens in infected mice. The increased release of mucins from goblet cells in the cecum and nearby proximal colon, and the subsequent thickening of the protective mucus barrier layer in the distal colon, were all dependent on the cytokines interleukin (IL)-18 and IL-22, as deficiencies in either cytokine resulted in reduced mucin secretion. Supplementation of IL-18 into IL-22 deficient mice restored mucin secretion, indicating that IL-22 acted upstream of IL-18 secretion during infection. In contrast, IL-18 and IL-22 independent signaling through Nlrp6 underlies only a modest, infection-induced increase in mucin secretion from goblet cells in the distal colon. These findings reveal that inflammasome signaling orchestrates multiple levels of protection centered on the intestinal epithelium, including pyroptosis and expulsion of infected enterocytes, as well as the release of mucins by goblet cells in the cecum and along the length of the colon. Our studies underscore the pivotal, multi-faceted role of inflammasome signaling in promoting host defense at the intestinal mucosal surface.


Asunto(s)
Células Caliciformes , Inflamasomas , Interleucina-18 , Interleucina-22 , Interleucinas , Mucosa Intestinal , Ratones Endogámicos C57BL , Mucina 2 , Salmonella typhimurium , Animales , Inflamasomas/metabolismo , Inflamasomas/inmunología , Salmonella typhimurium/inmunología , Ratones , Células Caliciformes/metabolismo , Mucina 2/metabolismo , Mucina 2/genética , Interleucinas/metabolismo , Interleucinas/genética , Interleucina-18/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Mucosa Intestinal/inmunología , Ratones Noqueados , Infecciones por Salmonella/inmunología , Infecciones por Salmonella/microbiología , Infecciones por Salmonella/metabolismo , Caspasa 1/metabolismo , Caspasa 1/genética , Caspasas Iniciadoras/metabolismo , Ciego/microbiología , Colon/microbiología , Colon/inmunología , Colon/metabolismo , Caspasas/metabolismo , Citocinas/metabolismo , Transducción de Señal , Mucinas/metabolismo , Salmonelosis Animal/inmunología , Salmonelosis Animal/microbiología , Receptores de Superficie Celular
19.
Aust N Z J Public Health ; 47(5): 100078, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37586128

RESUMEN

OBJECTIVE: While people from culturally and linguistically diverse (CALD) backgrounds have been identified as a priority for suicide prevention in Australia, little is known about suicide in CALD communities. We aim to describe the availability and quality of CALD data in the Victorian Suicide Register (VSR). METHODS: A retrospective consecutive case series review of suicides reported to the Coroners Court of Victoria during 2016 was conducted. Using the VSR, we identify suicides showing evidence of CALD identity and relevant variables were extracted and coded according to an adapted Australian Institute of Health and Welfare framework. RESULTS: During 2016, 126 of 652 suicides (19.3%, 95% confidence intervals 16.4-22.6) were flagged as showing evidence of CALD. The two most frequent CALD indicators for which information was recorded were country of birth and year of arrival. There was less information pertaining to citizenship, residency/visa status, preferred language, English language proficiency and religious affiliation. CONCLUSIONS: This study demonstrates that the VSR, like other databases, has substantial gaps in availability and quality of CALD data. IMPLICATIONS: A framework to capture richer data on cultural, religious and linguistic diversity when coding suicides is needed to inform policy on suicide prevention initiatives designed for CALD communities.

20.
J Racial Ethn Health Disparities ; 10(2): 942-951, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35476223

RESUMEN

Biologics are becoming an increasingly important part of patient care across Canada. Recent studies from the USA show that Black patients are less likely than White patients to receive biologic treatment for several medical conditions. The relative lack of race-based data in Canada makes it difficult to replicate such studies in Canada. As a result, there is a paucity of literature that explores the association between biologic usage and race in Canada. Our review aims to explore the factors that might be driving racial treatment disparity in Canada that likely parallels the inequalities found in the USA. We provide a summary of the available literature on the factors that contribute to biologic treatment hesitancy among Black and Indigenous populations in Canada. We highlight several solutions that have been proposed in the literature to address biologic treatment hesitancy. Our review found that biologic treatment decision at the individual level can be very complex as patient's decisions are influenced by social inputs from family and trusted community members, biologic-related factors (negative injection experience, fear of needles, formulation, and unfamiliarity), cultural tenets (beliefs, values, perception of illness), and historical and systemic factors (past research injustices, socioeconomic status, patient-physician relationship, clinical trial representation). Some proposed solutions to address biologic treatment hesitancy among Black and Indigenous populations include increasing the number of Black and Indigenous researchers involved in and leading clinical trials, formally training physicians and healthcare workers to deliver culturally competent care, and eliminating financial barriers to accessing medications. Further research is needed to characterize and address race-based new treatment inequalities and hesitancy in Canada.


Asunto(s)
Productos Biológicos , Población Negra , Pueblos Indígenas , Aceptación de la Atención de Salud , Humanos , Canadá , Asistencia Sanitaria Culturalmente Competente , Aceptación de la Atención de Salud/etnología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA