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1.
Cell ; 166(3): 755-765, 2016 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-27372738

RESUMO

To provide a detailed analysis of the molecular components and underlying mechanisms associated with ovarian cancer, we performed a comprehensive mass-spectrometry-based proteomic characterization of 174 ovarian tumors previously analyzed by The Cancer Genome Atlas (TCGA), of which 169 were high-grade serous carcinomas (HGSCs). Integrating our proteomic measurements with the genomic data yielded a number of insights into disease, such as how different copy-number alternations influence the proteome, the proteins associated with chromosomal instability, the sets of signaling pathways that diverse genome rearrangements converge on, and the ones most associated with short overall survival. Specific protein acetylations associated with homologous recombination deficiency suggest a potential means for stratifying patients for therapy. In addition to providing a valuable resource, these findings provide a view of how the somatic genome drives the cancer proteome and associations between protein and post-translational modification levels and clinical outcomes in HGSC. VIDEO ABSTRACT.


Assuntos
Proteínas de Neoplasias/genética , Neoplasias Císticas, Mucinosas e Serosas/genética , Neoplasias Ovarianas/genética , Proteoma , Acetilação , Instabilidade Cromossômica , Reparo do DNA , DNA de Neoplasias , Feminino , Dosagem de Genes , Humanos , Espectrometria de Massas , Fosfoproteínas/genética , Processamento de Proteína Pós-Traducional , Análise de Sobrevida
2.
Cell ; 149(4): 899-911, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-22579290

RESUMO

Fragile X syndrome (FXS), the leading monogenic cause of intellectual disability and autism, results from loss of function of the RNA-binding protein FMRP. Here, we show that FMRP regulates translation of neuronal nitric oxide synthase 1 (NOS1) in the developing human neocortex. Whereas NOS1 mRNA is widely expressed, NOS1 protein is transiently coexpressed with FMRP during early synaptogenesis in layer- and region-specific pyramidal neurons. These include midfetal layer 5 subcortically projecting neurons arranged into alternating columns in the prospective Broca's area and orofacial motor cortex. Human NOS1 translation is activated by FMRP via interactions with coding region binding motifs absent from mouse Nos1 mRNA, which is expressed in mouse pyramidal neurons, but not efficiently translated. Correspondingly, neocortical NOS1 protein levels are severely reduced in developing human FXS cases, but not FMRP-deficient mice. Thus, alterations in FMRP posttranscriptional regulation of NOS1 in developing neocortical circuits may contribute to cognitive dysfunction in FXS.


Assuntos
Córtex Cerebral/embriologia , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Síndrome do Cromossomo X Frágil/embriologia , Óxido Nítrico Sintase Tipo I/metabolismo , Animais , Córtex Cerebral/metabolismo , Proteína do X Frágil da Deficiência Intelectual/genética , Síndrome do Cromossomo X Frágil/metabolismo , Síndrome do Cromossomo X Frágil/fisiopatologia , Regulação da Expressão Gênica , Humanos , Camundongos , Camundongos Knockout , Neurogênese , Células Piramidais/metabolismo , Processamento Pós-Transcricional do RNA , Especificidade da Espécie
3.
Mol Cell Proteomics ; 23(1): 100687, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029961

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancer types, partly because it is frequently identified at an advanced stage, when surgery is no longer feasible. Therefore, early detection using minimally invasive methods such as blood tests may improve outcomes. However, studies to discover molecular signatures for the early detection of PDAC using blood tests have only been marginally successful. In the current study, a quantitative glycoproteomic approach via data-independent acquisition mass spectrometry was utilized to detect glycoproteins in 29 patient-matched PDAC tissues and sera. A total of 892 N-linked glycopeptides originating from 141 glycoproteins had PDAC-associated changes beyond normal variation. We further evaluated the specificity of these serum-detectable glycoproteins by comparing their abundance in 53 independent PDAC patient sera and 65 cancer-free controls. The PDAC tissue-associated glycoproteins we have identified represent an inventory of serum-detectable PDAC-associated glycoproteins as candidate biomarkers that can be potentially used for the detection of PDAC using blood tests.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Biomarcadores Tumorais/metabolismo , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Glicoproteínas , Espectrometria de Massas
4.
Bioorg Chem ; 144: 107176, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38330721

RESUMO

Repurposing drugs can significantly reduce the time and costs associated with drug discovery and development. However, many drug compounds possess intrinsic fluorescence, resulting in aberrations such as auto-fluorescence, scattering and quenching, in fluorescent high-throughput screening assays. To overcome these drawbacks, time-resolved technologies have received increasing attention. In this study, we have developed a rapid and efficient screening platform based on time-resolved emission spectroscopy in order to screen for inhibitors of the DNA repair enzyme, uracil-DNA glycosylase (UDG). From a database of 1456 FDA/EMA-approved drugs, sodium stibogluconate was discovered as a potent UDG inhibitor. This compound showed synergistic cytotoxicity against 5-fluorouracil-resistant cancer cells. This work provides a promising future for time-resolved technologies for high-throughput screening (HTS), allowing for the swift identification of bioactive compounds from previously overlooked scaffolds due to their inherent fluorescence properties.


Assuntos
Neoplasias da Próstata , Uracila-DNA Glicosidase , Humanos , Masculino , Uracila-DNA Glicosidase/química , Oligonucleotídeos , Gluconato de Antimônio e Sódio , Avaliação Pré-Clínica de Medicamentos , Reposicionamento de Medicamentos , Detecção Precoce de Câncer
5.
J Artif Organs ; 27(1): 57-64, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36752993

RESUMO

The AtriClip device enables the safe and reproducible epicardial clipping of the left atrial appendage. Transapical off-pump beating heart mitral valve repair using NeoChord DS100 Artificial Chordae Delivery System has matured and become more standardized. We aim to evaluate the feasibility of combining NeoChord repair and left atrial appendage exclusion in a single procedure through the same minithoracotomy in patients with mitral valve prolapse and atrial fibrillation. From 2018 to 2019, seven patients with severe mitral regurgitation and atrial fibrillation underwent transesophageal echocardiography-guided transapical off-pump mitral valve repair with the novel NeoChord DS 1000 system and concomitant left atrial appendage exclusion using the AtriClip Pro II device. Both procedures were performed via left mini-thoracotomy. The AtriClip device was applied after the NeoChord repair was done. All seven patients had less than moderate mitral regurgitation after the NeoChord repair and successful left atrial appendage occlusion. There were no device or procedure-related complications. Clinical follow-up revealed significant symptomatic improvement, and no cardiovascular complications were reported. Transesophageal echocardiography at 6-12 months post-procedure showed stable left atrial appendage occlusion with no residual flow between the left atrium and the left atrial appendage and a stump of less than 5 mm. Beating heart epicardial clipping of the left atrial appendage using AtriClip concomitant with transapical mitral valve repair using Neochord DS 1000 system is a feasible and safe treatment option in mitral valve prolapse and atrial fibrillation in patients with limited indications. However, its safety needs to be confirmed in a larger series of patients.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Prolapso da Valva Mitral , Humanos , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/cirurgia , Prolapso da Valva Mitral/complicações , Prolapso da Valva Mitral/cirurgia , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Fibrilação Atrial/complicações , Fibrilação Atrial/cirurgia , Estudos de Viabilidade , Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/cirurgia , Resultado do Tratamento , Cordas Tendinosas
6.
Heart Lung Circ ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38760188

RESUMO

BACKGROUND: Administrative healthcare databases can be utilised for research. The accuracy of the International Statistical Classification of Diseases and Related Health Problems, Tenth Edition, Australian Modification (ICD-10-AM) coding of cardiovascular conditions in New Zealand is not known and requires validation. METHOD: International Statistical Classification of Diseases and Related Health Problems, Tenth Edition, Australian Modification coded discharges for acute coronary syndrome (ACS), heart failure (HF) and atrial fibrillation (AF), in both primary and secondary diagnostic positions, were identified from four district health boards between 1 January 2019 and 31 June 2019. A sample was randomly selected for retrospective clinician review for evidence of the coded diagnosis according to contemporary diagnostic criteria. Positive predictive values (PPVs) for ICD-10-AM coding vs clinician review were calculated. This study is also known as All of New Zealand, Acute Coronary Syndrome-Quality Improvement (ANZACS-QI) 77. RESULTS: A total of 600 cases (200 for each diagnosis, 5.0% of total identified cases) were reviewed. The PPV of ACS was 93% (95% confidence interval [CI] 89%-96%), HF was 93% (95% CI 89%-96%) and AF was 96% (95% CI 92%-98%). There were no differences in PPV between district health boards. PPV for ACS were lower in Maori vs non-Maori (72% vs 96%; p=0.004), discharge from non-Cardiology vs Cardiology services (89% vs 96%; p=0.048) and ICD-10-AM coding for unstable angina vs myocardial infarction (81% vs 95%; p=0.011). PPV for HF were higher in the primary vs secondary diagnostic position (100% vs 89%; p=0.001). CONCLUSIONS: The PPVs of ICD-10-AM coding for ACS, HF, and AF were high in this validation study. ICD-10-AM coding can be used to identify these diagnoses in administrative databases for the purposes of healthcare evaluation and research.

7.
Heart Lung Circ ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38981830

RESUMO

BACKGROUND: Heart failure (HF) is associated with high mortality, but there are limited reports on the underlying cause of death. This study reports short-, medium- and long-term cause-specific mortality following first-ever HF hospitalisation in New Zealand. METHOD: First-ever HF hospitalisations were identified from hospital discharge coding between 2010 and 2013. Mortality outcomes were obtained via anonymised linkage to national datasets. Short (0-30 days), medium (31-364 days), and long-term (1-5 years) mortality rates were identified. Cause of death was identified from death certification coding and classified as cardiovascular and non-cardiovascular. Cox regression analysis was performed to adjust for confounding variables. RESULTS: A cohort of 34,264 individuals with first-ever HF hospitalisation were identified. Mean age was 75.8±13 years and 50.5% were male. A total of 21,637 (63.1%) died within 5 years of hospitalisation; 4,122 (12.0%) within the first 30 days, 6,358 (18.6%) between 31-364 days, and 11,157 (32.6%) between 1 and 5 years. Older age, male gender, Maori ethnicity, higher socioeconomic deprivation and increased comorbidity were independent factors associated with higher all-cause mortality. Cardiovascular causes accounted for 51% of total deaths. Cardiovascular mortality was 6.0%, 9.5%, and 16.7% at 30 days, 31-364 days, and 1-5 years, respectively. The most common causes of non-cardiovascular mortality were neoplasms, chronic respiratory diseases and infections, accounting for 14.6%, 11.0%, and 5.5% of total deaths respectively. Comorbidity was associated with higher non-cardiovascular mortality (hazard ratio [HR] 3.35; 95% confidence interval [CI] 3.16-3.55) but not cardiovascular mortality (HR 0.79; 95% CI 0.72-0.86). CONCLUSIONS: In New Zealand, mortality following first-ever HF hospitalisation is high. Non-cardiovascular death is common and there are ethnic inequities.

8.
Bioconjug Chem ; 34(10): 1727-1737, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37750807

RESUMO

Glutathione S-transferase is heterogeneously expressed in breast cancer cells and is therefore emerging as a potential diagnostic biomarker for studying the heterogeneity of breast cancers. However, available fluorescent probes for GSTs depend heavily on GSTs-catalyzed glutathione (GSH) nucleophilic substitution reactions, making them susceptible to interference by the high concentration of nucleophilic species in the cellular environment. Moreover, the functions of subcellular GSTs are generally overlooked due to the lack of suitable luminescence probes. Herein, we report a highly selective affinity-based luminescence probe 1 for GST in breast cancer cells through tethering a GST inhibitor, ethacrynic acid, to an iridium(III) complex. Compared to activity-based probes which require the use of GSH, this probe could image GST-pi in the mitochondria by directly adducting to GST-pi (or potentially GST-pi/GS) in living cells. Probe 1 possesses desirable photophysical properties including a lifetime of 911 ns, a Stokes shift of 343 nm, and high photostability. The "turn on" luminescence mode of the probe enables highly selective detection of the GST with a limit of detection of 1.01 µM, while its long emission lifetime allows sensitive detection in organic dye-spiked autofluorescence samples by a time-resolved mode. The probe was further applied to specifically and quantitatively visualize MDA-MB-231 cells via specific binding to mitochondrial GST, and could differentiate breast cell lines based on their expression levels of GST. To the best of our knowledge, this probe is the first affinity-based iridium(III) imaging probe for the subcellular GST. Our work provides a valuable tool for unmasking the diverse roles of a subcellular GST in living systems, as well as for studying the heterogeneity of breast cancers.


Assuntos
Neoplasias da Mama , Glutationa Transferase , Humanos , Feminino , Glutationa Transferase/metabolismo , Neoplasias da Mama/diagnóstico por imagem , Irídio , Ácido Etacrínico , Mitocôndrias/metabolismo , Glutationa/metabolismo
9.
Clin Proteomics ; 20(1): 25, 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37357306

RESUMO

BACKGROUND: Close to three-quarters of ovarian cancer cases are frequently diagnosed at an advanced stage, with more than 70% of them failing to respond to primary therapy and relapsing within 5 years. There is an urgent need to identify strategies for early detection of ovarian cancer recurrence, which may lead to earlier intervention and better outcomes. METHODS: A customized magnetic bead-based 8-plex immunoassay was evaluated using a Bio-Plex 200 Suspension Array System. Target protein levels were analyzed in sera from 58 patients diagnosed with advanced ovarian cancer (including 34 primary and 24 recurrent tumors) and 46 healthy controls. The clinical performance of these biomarkers was evaluated individually and in combination for their ability to detect recurrent ovarian cancer. RESULTS: An 8-plex immunoassay was evaluated with high analytical performance suitable for biomarker validation studies. Logistic regression modeling selected a two-marker panel of CA-125 and VCAM-1 that improved the performance of CA-125 alone in detecting recurrent ovarian cancer (AUC: 0.813 versus 0.700). At a fixed specificity of 83%, the two-marker panel significantly improved sensitivity in separating primary from recurrent tumors (70.8% versus 37.5%, P = 0.004), demonstrating that VCAM-1 was significantly complementary to CA-125 in detecting recurrent ovarian cancer. CONCLUSIONS: A two-marker panel of CA-125 and VCAM-1 showed strong diagnostic performance and improvement over the use of CA-125 alone in detecting recurrent ovarian cancer. The experimental results warrant further clinical validation to determine their role in the early detection of recurrent ovarian cancer.

10.
Clin Proteomics ; 20(1): 53, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017436

RESUMO

BACKGROUND: Diagnosis of liver disease at earlier stages can improve outcomes and reduce the risk of progression to malignancy. Liver biopsy is the gold standard for diagnosis of liver disease, but is invasive and sample acquisition errors are common. Serum biomarkers for liver function and fibrosis, combined with patient factors, may allow for noninvasive detection of liver disease. In this pilot study, we tested and validated the performance of an algorithm that combines GP73 and LG2m serum biomarkers with age and sex (GLAS) to differentiate between patients with liver disease and healthy individuals in two independent cohorts. METHODS: To develop the algorithm, prototype immunoassays were used to measure GP73 and LG2m in residual serum samples collected between 2003 and 2016 from patients with staged fibrosis and cirrhosis of viral or non-viral etiology (n = 260) and healthy subjects (n = 133). The performance of five predictive models using combinations of age, sex, GP73, and/or LG2m from the development cohort were tested. Residual samples from a separate cohort with liver disease (fibrosis, cirrhosis, or chronic liver disease; n = 395) and healthy subjects (n = 106) were used to validate the best performing model. RESULTS: GP73 and LG2m concentrations were higher in patients with liver disease than healthy controls and higher in those with cirrhosis than fibrosis in both the development and validation cohorts. The best performing model included both GP73 and LG2m plus age and sex (GLAS algorithm), which had an AUC of 0.92 (95% CI: 0.90-0.95), a sensitivity of 88.8%, and a specificity of 75.9%. In the validation cohort, the GLAS algorithm had an estimated an AUC of 0.93 (95% CI: 0.90-0.95), a sensitivity of 91.1%, and a specificity of 80.2%. In both cohorts, the GLAS algorithm had high predictive probability for distinguishing between patients with liver disease versus healthy controls. CONCLUSIONS: GP73 and LG2m serum biomarkers, when combined with age and sex (GLAS algorithm), showed high sensitivity and specificity for detection of liver disease in two independent cohorts. The GLAS algorithm will need to be validated and refined in larger cohorts and tested in longitudinal studies for differentiating between stable versus advancing liver disease over time.

11.
BMC Endocr Disord ; 23(1): 242, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37926822

RESUMO

Primary acquired hypothyroidism in children manifests with a myriad of clinical presentations. Clinical features can be insidious in nature, often under the guise of non-specific presentations to other subspecialties prior to referral to the endocrinologist. Growth failure is a hallmark feature in these children alongside their presenting clinical symptomology which needs to be identified through detailed history, physical examination and analysis of the growth charts. In this case series, we discuss 5 atypical presentations of acquired primary hypothyroidism with multisystemic involvement, including musculoskeletal, hepatobiliary, gynaecological and haematological manifestations. This is of importance as untreated hypothyroidism leads to fatigue, decreased physical activity, suboptimal height gain, disordered puberty and poor neurocognitive development in children with long term detrimental outcomes.


Assuntos
Hipotireoidismo , Tiroxina , Criança , Humanos , Tiroxina/uso terapêutico , Hipotireoidismo/complicações , Hipotireoidismo/diagnóstico , Puberdade
12.
Appetite ; 190: 107031, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37690619

RESUMO

Food parenting practices, especially Autonomy Support practices and Structure practices, have not been comprehensively studied among parents of children born with low birth weight in Asia. The aim of this study was to investigate food parenting practices among parents of preschoolers who were born with low (<2500 g) and normal birth weight (≥2500 g) in Singapore. We recruited 197 parents of pre-school children (aged 3-5 years) who completed a socio-demographic questionnaire and the HomeSTEAD questionnaire, which examined food parenting practices. Among parents, 98 (49.8%) and 99 (50.2%) had children who were normal (NBW) and low birth weight (LBW) respectively. Parents of children with LBW had lower scores in one Autonomy Support practice (Encouragement) and three Structure practices (Meal setting, Planning and preparation of healthy meals, Rules and limits around unhealthy foods), after controlling for ethnicity and parental education. Parents of children with LBW also scored higher in one Autonomy Support practice (Guided choices: when food is given). There were no significant differences in Coercive Control practices between parents of both groups. Healthcare professionals could use this information to assess parental needs when facilitating parents' positive food parenting practices, especially among children with low birth weight.

13.
Australas J Dermatol ; 64(3): e229-e232, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37387304

RESUMO

Acne vulgaris, a common dermatological condition that affects most adolescents and young adults, can indicate an underlying pathology if present prematurely in mid-childhood. Premature acne can be caused by premature adrenarche secondary to non-classical congenital adrenal hyperplasia (NC-CAH), a condition arising from 21-hydroxylase deficiency. This report describes a pair of monozygotic twin brothers with identical premature onset of acne, who were found to have an identical homozygous mutation in the promoter region of the CYP21A2 gene. While it is widely known that NCCAH is associated with genetic changes, the drive behind onset of adrenarche are widely unknown. As such, this report provokes thoughts on whether adrenarche could be influenced by adrenal genetic polymorphisms.


Assuntos
Acne Vulgar , Hiperplasia Suprarrenal Congênita , Puberdade Precoce , Masculino , Adolescente , Adulto Jovem , Humanos , Criança , Gêmeos Monozigóticos , Hiperplasia Suprarrenal Congênita/genética , Acne Vulgar/genética , Acne Vulgar/complicações , Esteroide 21-Hidroxilase/genética
14.
Heart Lung Circ ; 32(4): 487-496, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36641263

RESUMO

AIMS: More optimal dispensing of statins is associated with greater cholesterol lowering; however, it is not known whether this translates to improved outcomes following acute coronary syndrome (ACS). The aim of this study was to assess the association between various levels of statin adherence and outcomes following ACS. METHODS: Patients hospitalised with ACS who underwent coronary angiography between 2014-2018 were identified from the All New Zealand ACS Quality Improvement (ANZACS-QI) registry. Medication possession ratio (MPR) was used to assess statin adherence and calculated over 1 year post-discharge using linked pharmaceutical dispensing datasets. Optimal, adequate and suboptimal adherence was defined as an MPR of ≥1.0, 0.8-0.99 and 0-0.79, respectively. A combined outcome of all-cause mortality and rehospitalisation for atherosclerotic disease was identified from 1 year post-discharge through September 2021. Cox proportional hazard models were used to adjust for confounding variables. RESULTS: Of the 30,452 patients, 68% had optimal adherence, 15% adequate adherence and 16% had suboptimal adherence to statins. Mean follow-up was 3.6 years. Those with suboptimal adherence had a higher adjusted risk of the combined outcome compared with those with optimal adherence (HR 1.18, 95% CI 1.11-1.26). There was no significant difference in adjusted outcome between those with optimal and adequate adherence (HR 0.99, 95% CI 0.92-1.06). CONCLUSIONS: Suboptimal statin adherence following ACS is associated with an increased risk of mortality and rehospitalisation. An MPR cut-off of 0.8 seems reasonable to identify those at higher risk of cardiovascular events that could benefit the most from interventions to improve statin adherence and is appropriate as a target for quality improvement programs.


Assuntos
Síndrome Coronariana Aguda , Aterosclerose , Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Assistência ao Convalescente , Alta do Paciente , Aterosclerose/complicações , Adesão à Medicação
15.
Molecules ; 29(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38202749

RESUMO

A synthetic pathway to a novel 4-aryl-3,4-dihydro-2H-1,4-benzoxazine scaffold was developed and a series of compounds based on the scaffold were synthesised as potential anticancer agents. The 4-aryl-substituted compounds were prepared via Buchwald-Hartwig cross-coupling between substituted bromobenzenes and various 1,4-benzoxazines, which in turn were generated from a cascade hydrogenation and reductive amination one-pot reaction. These analogues exhibited moderate to good potency against various cancer cell lines. Structure-activity relationship analysis indicated that the inclusion of hydroxyl groups on ring A and ring B was beneficial to biological activity, while having a para-amino group on ring C significantly enhanced potency. Molecule 14f displayed the most potent anticancer activity (IC50 = 7.84-16.2 µM against PC-3, NHDF, MDA-MB-231, MIA PaCa-2, and U-87 MG cancer cell lines), indicating its potential as a lead compound for further structural optimisation. All the synthesised compounds were fully characterised with NMR, HMRS, and IR. The novel benzoxazine scaffold described in this study holds promise and deserves further in-depth studies.


Assuntos
Benzoxazinas , Bromobenzenos , Benzoxazinas/farmacologia , Hidrogenação , Aminação , Linhagem Celular
16.
J Bacteriol ; 204(7): e0013722, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35703565

RESUMO

Members of the AraC family of transcriptional regulators (AFTRs) control the expression of many genes important to cellular processes, including virulence. In Shigella species, the type III secretion system (T3SS), a key determinant for host cell invasion, is regulated by the three-tiered VirF/VirB/MxiE transcriptional cascade. Both VirF and MxiE belong to the AFTRs and are characterized as positive transcriptional regulators. Here, we identify a novel regulatory activity for MxiE and its coregulator IpgC, which manifests as a negative feedback loop in the VirF/VirB/MxiE transcriptional cascade. Our findings show that MxiE and IpgC downregulate the virB promoter and, hence, VirB protein production, thus decreasing VirB-dependent promoter activity at ospD1, one of the nearly 50 VirB-dependent genes. At the virB promoter, regions required for negative MxiE- and IpgC-dependent regulation were mapped and found to be coincident with regions required for positive VirF-dependent regulation. In tandem, negative MxiE- and IpgC-dependent regulation of the virB promoter only occurred in the presence of VirF, suggesting that MxiE and IpgC can function to counter VirF activation of the virB promoter. Lastly, MxiE and IpgC do not downregulate another VirF-activated promoter, icsA, demonstrating that this negative feedback loop targets the virB promoter. Our study provides insight into a mechanism that may reprogram Shigella virulence gene expression following type III secretion and provides the impetus to examine if MxiE and IpgC homologs in other important bacterial pathogens, such as Burkholderia pseudomallei and Salmonella enterica serovars Typhimurium and Typhi, coordinate similar negative feedback loops. IMPORTANCE The large AraC family of transcriptional regulators (AFTRs) control virulence gene expression in many bacterial pathogens. In Shigella species, the AraC/XylS protein MxiE and its coregulator IpgC positively regulate the expression of type III secretion system genes within the three-tiered VirF/VirB/MxiE transcriptional cascade. Our findings suggest a negative feedback loop in the VirF/VirB/MxiE cascade, in which MxiE and IpgC counter VirF-dependent activation of the virB promoter, thus making this the first characterization of negative MxiE- and IpgC-dependent regulation. Our study provides insight into a mechanism that likely reprograms Shigella virulence gene expression following type III secretion, which has implications for other important bacterial pathogens with functional homologs of MxiE and IpgC.


Assuntos
Regulação Bacteriana da Expressão Gênica , Shigella flexneri , Proteínas de Bactérias/metabolismo , Citarabina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Retroalimentação , Shigella flexneri/genética , Shigella flexneri/metabolismo , Transcrição Gênica , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo III/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
17.
J Urol ; 208(5): 1037-1045, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35830553

RESUMO

PURPOSE: We assessed whether Prostate Health Index results improve prediction of grade reclassification for men on active surveillance. METHODS AND MATERIALS: We identified men in Canary Prostate Active Surveillance Study with Grade Group 1 cancer. Outcome was grade reclassification to Grade Group 2+ cancer. We considered decision rules to maximize specificity with sensitivity set at 95%. We derived rules based on clinical data (R1) vs clinical data+Prostate Health Index (R3). We considered an "or"-logic rule combining clinical score and Prostate Health Index (R4), and a "2-step" rule using clinical data followed by risk stratification based on Prostate Health Index (R2). Rules were applied to a validation set, where values of R2-R4 vs R1 for specificity and sensitivity were evaluated. RESULTS: We included 1,532 biopsies (n = 610 discovery; n = 922 validation) among 1,142 men. Grade reclassification was seen in 27% of biopsies (23% discovery, 29% validation). Among the discovery set, at 95% sensitivity, R2 yielded highest specificity at 27% vs 17% for R1. In the validation set, R3 had best performance vs R1 with Δsensitivity = -4% and Δspecificity = +6%. There was slight improvement for R3 vs R1 for confirmatory biopsy (AUC 0.745 vs R1 0.724, ΔAUC 0.021, 95% CI 0.002-0.041) but not for subsequent biopsies (ΔAUC -0.012, 95% CI -0.031-0.006). R3 did not have better discrimination vs R1 among the biopsy cohort overall (ΔAUC 0.007, 95% CI -0.007-0.020). CONCLUSIONS: Among active surveillance patients, using Prostate Health Index with clinical data modestly improved prediction of grade reclassification on confirmatory biopsy and did not improve prediction on subsequent biopsies.


Assuntos
Próstata , Neoplasias da Próstata , Biópsia , Humanos , Masculino , Gradação de Tumores , Próstata/patologia , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Conduta Expectante/métodos
18.
Clin Proteomics ; 19(1): 36, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36266629

RESUMO

BACKGROUND: The identification of differentially expressed tumor-associated proteins and genomic alterations driving neoplasia is critical in the development of clinical assays to detect cancers and forms the foundation for understanding cancer biology. One of the challenges in the analysis of pancreatic ductal adenocarcinoma (PDAC) is the low neoplastic cellularity and heterogeneous composition of bulk tumors. To enrich neoplastic cells from bulk tumor tissue, coring, and laser microdissection (LMD) sampling techniques have been employed. In this study, we assessed the protein and KRAS mutation changes associated with samples obtained by these enrichment techniques and evaluated the fraction of neoplastic cells in PDAC for proteomic and genomic analyses. METHODS: Three fresh frozen PDAC tumors and their tumor-matched normal adjacent tissues (NATs) were obtained from three sampling techniques using bulk, coring, and LMD; and analyzed by TMT-based quantitative proteomics. The protein profiles and characterizations of differentially expressed proteins in three sampling groups were determined. These three PDACs and samples of five additional PDACs obtained by the same three sampling techniques were also subjected to genomic analysis to characterize KRAS mutations. RESULTS: The neoplastic cellularity of eight PDACs ranged from less than 10% to over 80% based on morphological review. Distinctive proteomic patterns and abundances of certain tumor-associated proteins were revealed when comparing the tumors and NATs by different sampling techniques. Coring and bulk tissues had comparable proteome profiles, while LMD samples had the most distinct proteome composition compared to bulk tissues. Further genomic analysis of bulk, cored, or LMD samples demonstrated that KRAS mutations were significantly enriched in LMD samples while coring was less effective in enriching for KRAS mutations when bulk tissues contained a relatively low neoplastic cellularity. CONCLUSIONS: In addition to bulk tissues, samples from LMD and coring techniques can be used for proteogenomic studies. The greatest enrichment of neoplastic cellularity is obtained with the LMD technique.

19.
FASEB J ; 35(4): e21447, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33742688

RESUMO

Acute urinary retention (AUR) is a common urological emergency and affects a significant patient population. The inability to eliminate urine may lead to permanent damage to the bladder's structure and functioning. However, we know little about the underlying molecular sequelae to the urine retention. To closely mirror the potential high pressures that patients with AUR could experience, we catheterized anesthetized female mice via the urethra and filled the bladder by pumping saline (25 µL/min) into the bladder lumen to 50 cm or 80 cm water pressure. A water column with designated height (50 or 80 cm) was then adjusted to maintain constant pressure in the bladder lumen for 30 minutes. Functional and morphological evaluations were performed from 0 to 24 hours after AUR treatment. Mice exhibited incontinence and overactivity with diminished voiding pressure. Significant injury was confirmed which revealed bladders with disrupted urothelial barrier, edematous lamina propria, and distorted muscle bundles. Bladder smooth muscle (BSM) from pressure-treated mice have significantly diminished contraction force, suggesting that bladder voiding dysfunction can be attributed to impaired BSM contractility. Indeed, dysregulation of acetylcholine and purinergic signaling pathways were demonstrated, indicating that reduced efficacy of these pathways contributes to impaired BSM contractility. Finally, altered expression of ß1-integrin and extracellular matrix mediated mechanotransduction pathways were detected, suggesting a profound remodeling process. These data demonstrated an easy to perform, quantifiable, and reproducible AUR mouse model, which mimics well the characteristics of human AUR patients, and our data generate new insights into the molecular mechanisms that occur following AUR.


Assuntos
Modelos Animais de Doenças , Bexiga Urinária/patologia , Retenção Urinária/patologia , Animais , Fenômenos Biomecânicos , Feminino , Regulação da Expressão Gênica , Camundongos , Contração Muscular , Músculo Liso/patologia , Bexiga Urinária/lesões , Bexiga Urinária/metabolismo , Retenção Urinária/metabolismo , Urodinâmica
20.
Am J Obstet Gynecol ; 226(5): 714.e1-714.e16, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34921802

RESUMO

BACKGROUND: Obesity compromises metabolic health and female fertility, yet not all obese women are similar in metabolic status. The extent to which fecundability is influenced by the metabolic health status of women who are overweight or obese before conception is unknown. OBJECTIVE: This study aimed to: (1) determine the metabolic health status, and (2) examine the association between metabolic health status and fecundability of overweight and obese women trying to conceive in the Singapore PREconception Study of long-Term maternal and child Outcomes cohort study. STUDY DESIGN: We conducted a prospective preconception cohort study of Asian women (Chinese, Malay, and Indian) aged 18 to 45 years trying to conceive who were treated from 2015 to 2017 in KK Women's and Children's Hospital in Singapore (n=834). We defined women to have metabolically unhealthy status if they: (1) met 3 or more modified Joint Interim Statement metabolic syndrome criteria; or (2) had homeostasis model assessment-insulin resistance index ≥2.5. Body mass index was categorized as normal (18.5-22.9 kg/m2), overweight (23-27.4 kg/m2), or obese (≥27.5 kg/m2) on the basis of cutoff points for Asian populations. Fecundability was measured by time to pregnancy in menstrual cycles within a year of enrolment. Discrete-time proportional hazards models were used to estimate fecundability odds ratios, with adjustment for confounders and accounting for left truncation and right censoring. RESULTS: Of 232 overweight women, 28 (12.1%) and 25 (10.8%) were metabolically unhealthy by metabolic syndrome ≥3 criteria and homeostasis model assessment-insulin resistance ≥2.5, respectively. Of 175 obese women, 54 (30.9%) and 93 (53.1%) were metabolically unhealthy by metabolic syndrome ≥3 criteria and homeostasis model assessment-insulin resistance ≥2.5, respectively. Compared with metabolically healthy normal-weight women, lower fecundability was observed in metabolically unhealthy overweight women on the basis of metabolic syndrome criteria (fecundability odds ratios, 0.38 [95% confidence interval, 0.15-0.92]) and homeostasis model assessment-insulin resistance (fecundability odds ratios, 0.68 [95% confidence interval, 0.33-1.39]), with metabolic syndrome criteria showing a stronger association. Metabolically unhealthy obese women showed lower fecundability than the healthy normal-weight reference group by both metabolic syndrome (fecundability odds ratios, 0.35; 95% confidence interval, 0.17-0.72) and homeostasis model assessment-insulin resistance criteria (fecundability odds ratios, 0.43; 95% confidence interval, 0.26-0.71). Reduced fecundability was not observed in overweight or obese women who showed healthy metabolic profiles by either definition. CONCLUSION: Overweight or obesity was not synonymous with having metabolic syndrome or insulin resistance. In our preconception cohort, metabolically unhealthy overweight and obese women showed reduced fecundability, unlike their counterparts who were metabolically healthy. These findings suggest that metabolic health status, rather than simply being overweight and obese per se, plays an important role in fecundability.


Assuntos
Resistência à Insulina , Síndrome Metabólica , Índice de Massa Corporal , Criança , Estudos de Coortes , Feminino , Fertilidade , Nível de Saúde , Humanos , Síndrome Metabólica/epidemiologia , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Gravidez , Estudos Prospectivos , Singapura/epidemiologia
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