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1.
J Asthma ; 60(10): 1907-1917, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37021838

RESUMO

OBJECTIVE: Asthma occurs in ∼17% of Australian pregnancies and is associated with adverse perinatal outcomes, which worsen with poor asthma control. Consequently, the South Australian 'Asthma in Pregnancy' perinatal guidelines were revised in 2012 to address management according to severity. This study investigated if these revised guidelines reduced the impact of maternal asthma on risks of adverse perinatal outcomes before (Epoch 1, 2006-2011) and after the revision (Epoch 2, 2013-2018). METHODS: Routinely collected perinatal and neonatal datasets from the Women's and Children's Hospital (Adelaide, Australia) were linked. Maternal asthma (prevalence:7.5%) was defined as asthma medication use or symptoms described to midwives. In imputation (n = 59131) and complete case datasets (n = 49594), analyses were conducted by inverse proportional weighting and multivariate logistic regression, accounting for confounders. RESULTS: Overall, maternal asthma was associated with increased risks of any antenatal corticosteroid treatment for threatened preterm birth (aOR 1.319, 95% CI 1.078-1.614), any Cesarean section (aOR 1.196, 95% CI 1.059-1.351), Cesarean section without labor (aOR 1.241, 95% CI 1.067-1.444), intrauterine growth restriction (IUGR, aOR 1.285, 95% CI 1.026-1.61), and small for gestational age (aOR 1.324, 95% CI 1.136-1.542). After guideline revision, asthma-associated risks of any Cesarean section (p < 0.001), any antenatal corticosteroids (p = 0.041), and small for gestational age (p = 0.050), but not IUGR and Cesarean section without labor, were reduced. CONCLUSIONS: Clinical practice guidelines based on the latest evidence do not guarantee clinical efficacy. Since adverse perinatal outcomes did not all improve, this work highlights the need to evaluate the ongoing impact of guidelines on clinical outcomes.


Assuntos
Asma , Complicações na Gravidez , Nascimento Prematuro , Criança , Gravidez , Feminino , Recém-Nascido , Humanos , Resultado da Gravidez/epidemiologia , Complicações na Gravidez/tratamento farmacológico , Complicações na Gravidez/epidemiologia , Cesárea , Estudos Retrospectivos , Nascimento Prematuro/epidemiologia , Asma/tratamento farmacológico , Asma/epidemiologia , Asma/complicações , Austrália
2.
Neurobiol Dis ; 181: 106128, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37075948

RESUMO

RGS14 is a complex multifunctional scaffolding protein that is highly enriched within pyramidal cells (PCs) of hippocampal area CA2. In these neurons, RGS14 suppresses glutamate-induced calcium influx and related G protein and ERK signaling in dendritic spines to restrain postsynaptic signaling and plasticity. Previous findings show that, unlike PCs of hippocampal areas CA1 and CA3, CA2 PCs are resistant to a number of neurological insults, including degeneration caused by temporal lobe epilepsy (TLE). While RGS14 is protective against peripheral injury, similar roles for RGS14 during pathological injury in hippocampus remain unexplored. Recent studies showed that area CA2 modulates hippocampal excitability, generates epileptiform activity and promotes hippocampal pathology in animal models and patients with TLE. Because RGS14 suppresses CA2 excitability and signaling, we hypothesized that RGS14 would moderate seizure behavior and early hippocampal pathology following seizure activity, possibly affording protection to CA2 PCs. Using kainic acid (KA) to induce status epilepticus (KA-SE) in mice, we show that the loss of RGS14 (RGS14 KO) accelerated onset of limbic motor seizures and mortality compared to wild type (WT) mice, and that KA-SE upregulated RGS14 protein expression in CA2 and CA1 PCs of WT. Our proteomics data show that the loss of RGS14 impacted the expression of a number of proteins at baseline and after KA-SE, many of which associated unexpectedly with mitochondrial function and oxidative stress. RGS14 was shown to localize to the mitochondria in CA2 PCs of mice and reduce mitochondrial respiration in vitro. As a readout of oxidative stress, we found that RGS14 KO dramatically increased 3- nitrotyrosine levels in CA2 PCs, which was greatly exacerbated following KA-SE and correlated with a lack of superoxide dismutase 2 (SOD2) induction. Assessing for hallmarks of seizure pathology in RGS14 KO, we unexpectedly found no differences in neuronal injury in CA2 PCs. However, we observed a striking and surprising lack of microgliosis in CA1 and CA2 of RGS14 KO compared to WT. Together, our data demonstrate a newly appreciated role for RGS14 in limiting intense seizure activity and pathology in hippocampus. Our findings are consistent with a model where RGS14 limits seizure onset and mortality and, after seizure, is upregulated to support mitochondrial function, prevent oxidative stress in CA2 PCs, and promote microglial activation in hippocampus.


Assuntos
Epilepsia do Lobo Temporal , Proteínas RGS , Estado Epiléptico , Animais , Camundongos , Hipocampo/metabolismo , Convulsões , Células Piramidais/metabolismo , Epilepsia do Lobo Temporal/metabolismo , Estresse Oxidativo , Ácido Caínico/toxicidade , Proteínas RGS/efeitos adversos , Proteínas RGS/metabolismo
3.
Ultrasound Obstet Gynecol ; 61(3): 377-385, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35866888

RESUMO

OBJECTIVES: Fetal growth restriction (FGR) is often secondary to placental dysfunction and is suspected prenatally based on biometric or circulatory abnormalities detected on ultrasound. The aims of this study were to compare the screening performance of the Society for Maternal-Fetal Medicine (SMFM) biometric criteria (estimated fetal weight (EFW) or abdominal circumference (AC) < 10th centile) with that of the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG)-endorsed Delphi consensus criteria for late FGR for delivery of a small-for-gestational-age (SGA) infant at term, emergency Cesarean section (CS) for non-reassuring fetal status (NRFS), perinatal mortality and composite severe neonatal morbidity. METHODS: We classified retrospectively non-anomalous singleton infants as having late FGR (diagnosed ≥ 32 weeks) according to SMFM and ISUOG/Delphi criteria in a cohort of women who had been referred to the Mater Mother's Hospital, Brisbane, Australia and who delivered at term between January 2014 and December 2020. The study outcomes were delivery of a SGA infant (birth weight (BW) < 10th or < 3rd centile), emergency CS for NRFS, perinatal mortality (defined as stillbirth or neonatal death within 28 days of a live birth) and a composite of severe neonatal morbidity. We assessed the screening performance of various ultrasound variables by calculating the sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, false-positive and false-negative rates, positive likelihood ratio (LR+) and negative likelihood ratio. RESULTS: The SMFM and ISUOG/Delphi consensus criteria collectively classified 1030 cases as having late FGR. Of these, 400 cases were classified by both SMFM and ISUOG/Delphi criteria, whilst 548 cases were classified using only SMFM criteria and 82 cases were classified only by ISUOG/Delphi criteria. Prenatal detection of late FGR by SMFM and ISUOG/Delphi criteria was associated with increased odds of delivery of an infant with BW < 10th centile (SMFM: adjusted odds ratio (aOR), 133.0 (95% CI, 94.7-186.6); ISUOG/Delphi: aOR, 69.5 (95% CI, 49.1-98.2)) or BW < 3rd centile (SMFM: aOR, 348.7 (95% CI, 242.6-501.2); ISUOG/Delphi: aOR, 215.4 (95% CI, 148.4-312.7)). Compared with the SMFM criteria, the ISUOG/Delphi criteria were associated with lower odds (aOR, 0.5 (95% CI, 0.3-0.8)) of predicting a SGA infant with BW < 10th centile, but higher odds of predicting emergency CS for NRFS (aOR, 2.30 (95% CI, 1.14-4.66)) and composite neonatal morbidity (aOR, 1.22 (95% CI, 1.05-1.41)). Both SMFM and ISUOG/Delphi criteria were associated with high LR+, specificity, PPV and NPV for the prediction of infants with BW < 10th and BW < 3rd centile. However, both methods functioned much less efficiently for the prediction of composite severe neonatal morbidity or emergency CS for NRFS, with LR+ < 10. The SMFM biometric criteria alone, particularly AC < 3rd centile, had the highest LR+ values for the prediction of perinatal mortality. CONCLUSION: Both the SMFM and ISUOG/Delphi criteria had strong screening potential for the detection of infants with BW < 10th or < 3rd centile but not for adverse neonatal outcome. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Retardo do Crescimento Fetal , Morte Perinatal , Recém-Nascido , Gravidez , Lactente , Feminino , Humanos , Retardo do Crescimento Fetal/diagnóstico por imagem , Cesárea , Estudos Retrospectivos , Perinatologia , Técnica Delphi , Placenta , Ultrassonografia Pré-Natal/métodos , Recém-Nascido Pequeno para a Idade Gestacional , Peso ao Nascer , Peso Fetal , Biometria , Idade Gestacional
4.
Exp Gerontol ; 166: 111884, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35788023

RESUMO

INTRODUCTION: Sarcopenia, the age-related loss of skeletal muscle strength and mass, carries a significant burden for affected individuals. There has been little investigation of sarcopenia using experimental medicine techniques to study human muscle tissue in detail. The aim of the Muscle Ageing Sarcopenia Studies Lifecourse (MASS_Lifecourse) study is to recruit up to 160 participants, equally divided between females and males between ages 45 and 85 years for detailed phenotyping of skeletal muscle health. Here we describe the protocol for the study and the characteristics of the first 80 participants. METHODS: We are recruiting participants from three sources in the north-east of England. Study fieldwork comprises a home visit (or videocall) for consent and assessment of health, cognition, lifestyle, and wellbeing. This is followed by a visit to a clinical research facility for assessment of sarcopenia status and collection of samples including a vastus lateralis muscle biopsy. We produced descriptive statistics for the first 80 participants, including expressing their grip strength relative to normative data in the form of Z-scores. RESULTS: The first 80 participants (53.8 % female) covered the target ages, ranging from 48 to 84 years. They were regularly physically active, reported good physical function and had a prevalence of sarcopenia (including probable sarcopenia) of 11.3 % based on the revised European consensus. Their grip strength was similar to that in the general population, with a mean Z-score of 0.09 standard deviations (95 % CI: -1.64, 1.83) above that expected. CONCLUSIONS: The MASS_Lifecourse study combines comprehensive health and lifestyle data with a range of biological samples including skeletal muscle. The findings from planned analyses should contribute to improvements in the diagnosis, treatment, and prevention of sarcopenia.


Assuntos
Sarcopenia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Feminino , Força da Mão/fisiologia , Humanos , Masculino , Força Muscular , Músculo Esquelético/fisiologia , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia
5.
Int J Obstet Anesth ; 44: 81-89, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32823251

RESUMO

BACKGROUND: Postoperative nausea and vomiting is one of the most common anaesthetic complications of caesarean section. This study examined the association between hyperemesis gravidarum during pregnancy and nausea and vomiting after caesarean section. METHODS: A single-centre, retrospective cohort study, using electronic databases of patients with and without hyperemesis gravidarum, undergoing caesarean section from 2015 to 2019. The incidence and severity of postoperative nausea and vomiting were established by a review of the documentation of administration of postoperative anti-emetics within the 24-h period after surgery, and examined using univariable, multivariable binary and ordered logistic regression models. RESULTS: Data were compared for 76 patients with hyperemesis gravidarum and 315 patients without the condition. The incidence of postoperative nausea and vomiting in the hyperemesis group versus the non-hyperemesis group was 43.4% vs 29.6%, respectively. The odds of experiencing postoperative nausea and vomiting was 1.95 times higher in women with hyperemesis gravidarum than in those without (aOR 1.95, 95% CI 1.13 to 3.36, P=0.016). The odds of having more severe postoperative nausea and vomiting were greater in the hyperemesis gravidarum group (aOR 1.91, 95% CI 1.14 to 3.20, P=0.014). CONCLUSION: Patients with hyperemesis gravidarum are more likely to develop nausea and vomiting after caesarean section, and this is likely to be of greater severity than in those without the condition. This finding should assist the effective provision of intra-operative and postoperative anti-emetics for patients with hyperemesis gravidarum undergoing caesarean section.


Assuntos
Cesárea , Hiperêmese Gravídica/epidemiologia , Náusea e Vômito Pós-Operatórios/epidemiologia , Adulto , Estudos de Coortes , Comorbidade , Feminino , Humanos , Incidência , Gravidez , Estudos Retrospectivos , Índice de Gravidade de Doença
6.
Int J Parasitol Parasites Wildl ; 9: 25-35, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30976514

RESUMO

Within-host competition can affect outcomes of infections when parasites occupy the same niche. We investigated within-host competition and infection outcomes in Chinook salmon exposed to two genotypes of Ceratonova shasta (myxozoan parasite). We assessed i) virulence (host mortality, median days to death), ii) within-host competition (abundance in host), and iii) success (spore production, proportion of myxospore-producing hosts) following concurrent and sequential exposures to single or mixed-genotype treatments. In single treatments, genotype-I replicated faster, and caused higher and earlier host mortality (higher virulence) but genotype-II produced more myxospores (higher success). In mixed treatments, costs of competition were observed for both genotypes evidenced by reduced replication or myxospore production following concurrent exposures, but only the less-virulent genotype suffered costs of competition when hosts were exposed to genotypes sequentially. To understand potential host effects on competition outcomes, we characterized systemic (spleen) and local (intestine) cytokine and immunoglobulin expression in single and mixed infections. We observed delayed systemic and immunosuppressive responses to the virulent genotype (I), rapid, localized and non-suppressive responses to the less-virulent genotype (II), and a combination of responses to mixed-genotypes. Thus, competition outcomes favoring the virulent genotype may be partially explained by the localized response to genotype-II that facilitates myxospore production (success) offsetting the systemic response to genotype-I that results in early inflammation and immunosuppression (that increases onset of mortality). This evidence for different but simultaneous responses to each genotype suggests selection should favor the exclusion of the weaker competitor and the evolution of increased virulence in the stronger competitor because the outcome was generally more costly for the less-virulent genotype. With caveats, our results are relevant for understanding infection outcomes in commercially and ecologically important salmonids in C. shasta endemic regions where mixed infections are commonplace.

7.
Ir Med J ; 110(7): 617, 2017 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-29168999

RESUMO

Gestational Diabetes Mellitus (GDM) is a growing concern and poses serious health risks to both mother and child1. The current study explores the psychological determinants of exercise behaviour in a sample of pregnant women with GDM. A cross-sectional survey design was employed to examine exercise behaviour, illness perceptions, perceived barriers and benefits, exercise beliefs, and exercise self-efficacy using validated questionnaires. A sample of 46 pregnant women was recruited from University College Hospital Galway, Letterkenny General Hospital, Cork University Hospital and Mayo General Hospital in Castlebar. Participant's varied; age (22-44 years), body mass index (19-41). High mean scores for Personal Control (24.5) and Treatment Control (30.2) subscales indicated strongly held positive beliefs in relation to controllability of the illness. Total MET-min/week score was not related to any psychological variables. Analysis of the IPQ-R data revealed 'diet' (n=37, 80.4%) as the most referred to cause of diabetes. Exercise belief data identified "managing weight gain" (n= 21, 45.7%), and "losing baby weight" (n= 31, 67.4%) as the most frequent beliefs for engaging in physical activity during pregnancy and post pregnancy. Further research on the psychological determinants of physical activity behaviour among this population group is needed in order to create successful intervention strategies.


Assuntos
Diabetes Gestacional/psicologia , Exercício Físico/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Estudos Transversais , Dieta , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Gravidez , Aumento de Peso
8.
Int J Tuberc Lung Dis ; 21(3): 338-344, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28225346

RESUMO

OBJECTIVES: Tuberculosis (TB) is a major cause of morbidity and mortality in human immunodeficiency virus (HIV) infected patients. However, anti-tuberculosis drugs can cause cutaneous adverse drug reactions (CADRs). This study was conducted to evaluate differences in CADR incidence between low and high CD4 cell count in patients with low and high CD4 cell count and to identify other risk factors for CADR in HIV-TB co-infected patients. DESIGN: In a retrospective cohort of adult HIV-TB co-infected patients receiving standard anti-tuberculosis treatment between January 2008 and December 2015 at Vajira Hospital, Bangkok, Thailand, baseline demographic, clinical characteristics and factors associated with CADRs, including CD4 cell count status, were collected. RESULTS: Of 307 patients enrolled, CADRs occurred in 48 during the 6-month period of anti-tuberculosis treatment (incidence rate 0.41 events/person-year). Maculopapular rash was the most prevalent CADR. Low CD4 cell count was not associated with CADRs. Cox regression analysis revealed that moderate decrease in the glomerular filtration rate, history of drug hypersensitivity and concomitant cotrimoxazole use were all associated with CADRs. Concomitant antiretroviral therapy use was associated with lower risk of CADRs. No difference in the time to CADRs between patients with lower and higher CD4 cell count could be demonstrated. CONCLUSION: CADRs are common in HIV-TB co-infected patients. Early recognition and prompt withdrawal of the offending agent can prevent complications and improve TB care.


Assuntos
Antituberculosos/efeitos adversos , Toxidermias/etiologia , Infecções por HIV/complicações , Tuberculose/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Adolescente , Adulto , Fármacos Anti-HIV/uso terapêutico , Antituberculosos/administração & dosagem , Contagem de Linfócito CD4 , Estudos de Coortes , Toxidermias/diagnóstico , Toxidermias/epidemiologia , Feminino , Seguimentos , Infecções por HIV/tratamento farmacológico , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Tailândia , Combinação Trimetoprima e Sulfametoxazol/administração & dosagem , Combinação Trimetoprima e Sulfametoxazol/efeitos adversos , Adulto Jovem
9.
BMC Cancer ; 16: 553, 2016 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-27465249

RESUMO

BACKGROUND: Many urothelial carcinomas (UC) contain activating PIK3CA mutations. In telomerase-immortalized normal urothelial cells (TERT-NHUC), ectopic expression of mutant PIK3CA induces PI3K pathway activation, cell proliferation and cell migration. However, it is not clear whether advanced UC tumors are PIK3CA-dependent and whether PI3K pathway inhibition is a good therapeutic option in such cases. METHODS: We used retrovirus-mediated delivery of shRNA to knock down mutant PIK3CA in UC cell lines and assessed effects on pathway activation, cell proliferation, migration and tumorigenicity. The effect of the class I PI3K inhibitor GDC-0941 was assessed in a panel of UC cell lines with a range of known molecular alterations in the PI3K pathway. RESULTS: Specific knockdown of PIK3CA inhibited proliferation, migration, anchorage-independent growth and in vivo tumor growth of cells with PIK3CA mutations. Sensitivity to GDC-0941 was dependent on hotspot PIK3CA mutation status. Cells with rare PIK3CA mutations and co-occurring TSC1 or PTEN mutations were less sensitive. Furthermore, downstream PI3K pathway alterations in TSC1 or PTEN or co-occurring AKT1 and RAS gene mutations were associated with GDC-0941 resistance. CONCLUSIONS: Mutant PIK3CA is a potent oncogenic driver in many UC cell lines and may represent a valuable therapeutic target in advanced bladder cancer.


Assuntos
Carcinoma de Células de Transição/metabolismo , Transformação Celular Neoplásica/metabolismo , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Animais , Western Blotting , Carcinoma de Células de Transição/genética , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Transformação Celular Neoplásica/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Neoplasias da Bexiga Urinária/genética
10.
Ann Oncol ; 27(7): 1311-6, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27091807

RESUMO

BACKGROUND: Fibroblast growth factor receptor 3 (FGFR3) is an actionable target in bladder cancer. Preclinical studies show that anti-FGFR3 treatment slows down tumor growth, suggesting that this tyrosine kinase receptor is a candidate for personalized bladder cancer treatment, particularly in patients with mutated FGFR3. We addressed tumor heterogeneity in a large multicenter, multi-laboratory study, as this may have significant impact on therapeutic response. PATIENTS AND METHODS: We evaluated possible FGFR3 heterogeneity by the PCR-SNaPshot method in the superficial and deep compartments of tumors obtained by transurethral resection (TUR, n = 61) and in radical cystectomy (RC, n = 614) specimens and corresponding cancer-positive lymph nodes (LN+, n = 201). RESULTS: We found FGFR3 mutations in 13/34 (38%) T1 and 8/27 (30%) ≥T2-TUR samples, with 100% concordance between superficial and deeper parts in T1-TUR samples. Of eight FGFR3 mutant ≥T2-TUR samples, only 4 (50%) displayed the mutation in the deeper part. We found 67/614 (11%) FGFR3 mutations in RC specimens. FGFR3 mutation was associated with pN0 (P < 0.001) at RC. In 10/201 (5%) LN+, an FGFR3 mutation was found, all concordant with the corresponding RC specimen. In the remaining 191 cases, RC and LN+ were both wild type. CONCLUSIONS: FGFR3 mutation status seems promising to guide decision-making on adjuvant anti-FGFR3 therapy as it appeared homogeneous in RC and LN+. Based on the results of TUR, the deep part of the tumor needs to be assessed if neoadjuvant anti-FGFR3 treatment is considered. We conclude that studies on the heterogeneity of actionable molecular targets should precede clinical trials with these drugs in the perioperative setting.


Assuntos
Biomarcadores Tumorais/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Adulto , Idoso , Tomada de Decisão Clínica , Cistectomia , Feminino , Regulação Neoplásica da Expressão Gênica , Heterogeneidade Genética , Humanos , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Período Perioperatório , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia
11.
J Aquat Anim Health ; 27(1): 20-4, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25494609

RESUMO

The recent identification of multiple genotypes of the salmonid parasite Ceratonova shasta with different virulence levels in Chinook Salmon Oncorhynchus tshawytscha suggests that it is possible to immunize fish against subsequent infection and disease. We hypothesized that exposure of Chinook Salmon to the less-virulent parasite genotype (II) prior to the more virulent parasite genotype (I) would decrease disease and/or result in fewer mature parasites compared with fish only infected with the more virulent genotype. To test this hypothesis, fish were challenged in a combination of field and laboratory exposures, and we measured infection prevalence, percent morbidity, and mature parasite production. Neither mortality nor mature parasite production were reduced when fish were exposed to genotype II prior to genotype I compared with fish exposed only to genotype I, suggesting that protection against C. shasta using a less-virulent genotype of the parasite does not occur.


Assuntos
Doenças dos Peixes/parasitologia , Myxozoa/fisiologia , Doenças Parasitárias em Animais/imunologia , Salmão , Animais , Doenças dos Peixes/imunologia , Doenças Parasitárias em Animais/parasitologia
13.
Anal Biochem ; 442(1): 110-7, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23911526

RESUMO

Estimation of total protein concentration is an essential step in any protein- or peptide-centric analysis pipeline. This study demonstrates that urobilin, a breakdown product of heme and a major constituent of urine, interferes considerably with the bicinchoninic acid (BCA) assay. This interference is probably due to the propensity of urobilin to reduce cupric ions (Cu(2+)) to cuprous ions (Cu(1+)), thus mimicking the reduction of copper by proteins, which the assay was designed to do. In addition, it is demonstrated that the Bradford assay is more resistant to the influence of urobilin and other small molecules. As such, urobilin has a strong confounding effect on the estimate of total protein concentrations obtained by BCA assay and thus this assay should not be used for urinary protein quantification. It is recommended that the Bradford assay be used instead.


Assuntos
Proteínas/análise , Quinolinas/química , Urobilina/metabolismo , Urobilina/urina , Cobre/química , Cobre/metabolismo , Humanos , Proteínas/química , Quinolinas/metabolismo , Valores de Referência , Sensibilidade e Especificidade
14.
Med Phys ; 40(6): 061711, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23718590

RESUMO

PURPOSE: High-Z material in computed tomography (CT) yields metal artifacts that degrade image quality and may cause substantial errors in dose calculation. This study couples a metal artifact reduction (MAR) algorithm with enhanced 16-bit depth (vs standard 12-bit) to quantify potential gains in image quality and dosimetry. METHODS: Extended CT to electron density (CT-ED) curves were derived from a tissue characterization phantom with titanium and stainless steel inserts scanned at 90-140 kVp for 12- and 16-bit reconstructions. MAR was applied to sinogram data (Brilliance BigBore CT scanner, Philips Healthcare, v.3.5). Monte Carlo simulation (MC-SIM) was performed on a simulated double hip prostheses case (Cerrobend rods embedded in a pelvic phantom) using BEAMnrc∕Dosxyz (400,000,0000 histories, 6X, 10 × 10 cm(2) beam traversing Cerrobend rod). A phantom study was also conducted using a stainless steel rod embedded in solid water, and dosimetric verification was performed with Gafchromic film analysis (absolute difference and gamma analysis, 2% dose and 2 mm distance to agreement) for plans calculated with Anisotropic Analytic Algorithm (AAA, Eclipse v11.0) to elucidate changes between 12- and 16-bit data. Three patients (bony metastases to the femur and humerus, and a prostate cancer case) with metal implants were reconstructed using both bit depths, with dose calculated using AAA and derived CT-ED curves. Planar dose distributions were assessed via matrix analyses and using gamma criteria of 2%∕2 mm. RESULTS: For 12-bit images, CT numbers for titanium and stainless steel saturated at 3071 Hounsfield units (HU), whereas for 16-bit depth, mean CT numbers were much larger (e.g., titanium and stainless steel yielded HU of 8066.5 ± 56.6 and 13,588.5 ± 198.8 for 16-bit uncorrected scans at 120 kVp, respectively). MC-SIM was well-matched between 12- and 16-bit images except downstream of the Cerrobend rod, where 16-bit dose was ∼6.4% greater than 12-bit. Absolute film dosimetry in a region downstream of a stainless steel rod revealed that 16-bit calculated dose, with and without MAR, agreed more closely with film results (1%-2% less than film) as compared to 12-bit reconstructions (5.6%-6.5% less than film measurements). Gamma analysis revealed that 16-bit dose calculations were better matched to film results than 12-bit (∼10% higher pass rates for 16-bit). Similar results were observed in two patient cases; the largest discrepancy was observed for a femur case where 12-bit doses, both with and without MAR correction, were 6-7 Gy lower (∼17%-20% of the prescription dose) as compared to 16-bit dose calculations. However, when beams are not directly traversing metal, such as a prostate cancer case with bilateral hip prostheses; the impact of 16-bit reconstruction was diminished. CONCLUSIONS: These results suggest that it may be desirable to implement 16-bit MAR-corrected images for treatment planning purposes, which can provide a more accurate dosimetric approach coupled with improved visualization by suppression of CT artifacts.


Assuntos
Algoritmos , Artefatos , Metais , Próteses e Implantes , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Imagens de Fantasmas , Radioterapia Guiada por Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/instrumentação
15.
Br J Cancer ; 108(6): 1368-77, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23549060

RESUMO

BACKGROUND: Necdin (NDN) expression is downregulated in telomerase-immortalised normal human urothelial cells. Telomerase-immortalised normal human urothelial cells have no detected genetic alterations. Accordingly, many of the genes whose expression is altered following immortalisation are those for which epigenetic silencing is reported. METHODS: NDN expression was examined in normal tissues and tumour cell lines by quantitative real-time PCR and immunoblotting. Immunohistochemistry was performed on urothelial carcinoma (UC). Urothelial carcinoma and UC cell lines were subject to HumanMethylation27 BeadChip Array-based methylation analyses. Mutation screening was performed. The functional significance of NDN expression was investigated using retroviral-mediated downregulation or overexpression. RESULTS: NDN protein was widely expressed in normal tissues. Loss of expression was observed in 38 out of 44 (86%) of UC cell lines and 19 out of 25 (76%) of non-UC cell lines. Loss of NDN protein was found in the majority of primary UC. Oncomine analysis demonstrated downregulation of expression in multiple tumour types. In UC, tumour-specific hypermethylation of NDN and key CpG sites where hypermethylation correlated with reduced expression were identified. Six novel mutations, including some of predicted functional significance, were identified in colorectal and ovarian cancer cell lines. Functional studies showed that NDN could suppress colony formation at low cell density and affect anchorage-independent growth and anoikis in vitro. CONCLUSION: NDN is a novel tumour suppressor candidate that is downregulated and hypermethylated or mutated in cancer.


Assuntos
Biomarcadores Tumorais/genética , Metilação de DNA , Genes Supressores de Tumor , Mutação/genética , Neoplasias/genética , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Proliferação de Células , Células Cultivadas , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Immunoblotting , Técnicas Imunoenzimáticas , Neoplasias/patologia , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Urotélio/metabolismo
16.
Med Phys ; 40(3): 031719, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23464314

RESUMO

PURPOSE: Latest generation linear accelerators (linacs), i.e., TrueBeam (Varian Medical Systems, Palo Alto, CA) and its stereotactic counterpart, TrueBeam STx, have several unique features, including high-dose-rate flattening-filter-free (FFF) photon modes, reengineered electron modes with new scattering foil geometries, updated imaging hardware/software, and a novel control system. An evaluation of five TrueBeam linacs at three different institutions has been performed and this work reports on the commissioning experience. METHODS: Acceptance and commissioning data were analyzed for five TrueBeam linacs equipped with 120 leaf (5 mm width) MLCs at three different institutions. Dosimetric data and mechanical parameters were compared. These included measurements of photon beam profiles (6X, 6XFFF, 10X, 10XFFF, 15X), photon and electron percent depth dose (PDD) curves (6, 9, 12 MeV), relative photon output factors (Scp), electron cone factors, mechanical isocenter accuracy, MLC transmission, and dosimetric leaf gap (DLG). End-to-end testing and IMRT commissioning were also conducted. RESULTS: Gantry/collimator isocentricity measurements were similar (0.27-0.28 mm), with overall couch/gantry/collimator values of 0.46-0.68 mm across the three institutions. Dosimetric data showed good agreement between machines. The average MLC DLGs for 6, 10, and 15 MV photons were 1.33 ± 0.23, 1.57 ± 0.24, and 1.61 ± 0.26 mm, respectively. 6XFFF and 10XFFF modes had average DLGs of 1.16 ± 0.22 and 1.44 ± 0.30 mm, respectively. MLC transmission showed minimal variation across the three institutions, with the standard deviation <0.2% for all linacs. Photon and electron PDDs were comparable for all energies. 6, 10, and 15 MV photon beam quality, %dd(10)x varied less than 0.3% for all linacs. Output factors (Scp) and electron cone factors agreed within 0.27%, on average; largest variations were observed for small field sizes (1.2% coefficient of variation, 10 MV, 2 × 2 cm(2)) and small cone sizes (<1% coefficient of variation, 6 × 6 cm(2) cone), respectively. CONCLUSIONS: Overall, excellent agreement was observed in TrueBeam commissioning data. This set of multi-institutional data can provide comparison data to others embarking on TrueBeam commissioning, ultimately improving the safety and quality of beam commissioning.


Assuntos
Aceleradores de Partículas , Elétrons , Fótons , Radiometria , Radioterapia de Intensidade Modulada , Fatores de Tempo
17.
Br J Cancer ; 107(8): 1392-8, 2012 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-22976798

RESUMO

BACKGROUND: Multiple clinical risk factors and genetic profiles have been demonstrated to predict progression of non-muscle invasive bladder cancer; however, no easily clinical applicable gene signature has been developed to predict disease progression independent of disease stage and grade. METHODS: We measured the intra-patient variation of an 88-gene progression signature using 39 metachronous tumours from 17 patients. For delineation of the optimal quantitative reverse transcriptase PCR panel of markers, we used 115 tumour samples from patients in Denmark, Sweden, UK and Spain. RESULTS: Analysis of intra-patient variation of the molecular markers showed 71% similar classification results. A final panel of 12 genes was selected, showing significant correlation with outcome. In multivariate Cox regression analysis, we found that the 12-gene signature was an independent prognostic factor (hazard ratio=7.4 (95% confidence interval: 3.4-15.9), P<0.001) when adjusting for stage, grade and treatment. Independent validation of the 12-gene panel and the determined cut-off values is needed and ongoing. CONCLUSION: Intra-patient marker variation in metachronous tumours is present. Therefore, to increase test sensitivity, it may be necessary to test several metachronous tumours from a patient's disease course. A PCR-based 12-gene signature significantly predicts disease progression in patients with non-muscle invasive bladder cancer.


Assuntos
Segunda Neoplasia Primária/genética , Reação em Cadeia da Polimerase , Análise Serial de Tecidos , Neoplasias da Bexiga Urinária/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Segunda Neoplasia Primária/patologia , Prognóstico , Transferência de Tecnologia , Neoplasias da Bexiga Urinária/patologia
18.
J Fish Dis ; 35(10): 725-32, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22808922

RESUMO

Ceratomyxa shasta is a myxozoan parasite of salmonid fish. In natural communities, distinct genotypes of the parasite are associated with different salmonid hosts. To test the hypothesis that genotypes of C. shasta cause differential mortality, the polychaete host was experimentally infected with different parasite genotypes. Genotype I was obtained from Chinook salmon, Oncorhynchus tshawytscha, and genotype II from either coho salmon, O. kisutch, or rainbow trout, O. mykiss, We then challenged four salmonid strains: Chinook and coho salmon that occur in sympatry with the parasite and allopatric Chinook salmon and rainbow trout. Parasite genotype I caused mortality only in Chinook strains, although mortality in the allopatric strain also occurred from exposure to genotype II. A second experiment demonstrated that genotype II could be separated into two biotypes based on differential mortality in rainbow trout and coho salmon. These differential patterns of mortality as a result of infection by certain genotypes of C. shasta support field observations and suggest a co-evolutionary relationship between these parasites and their hosts.


Assuntos
Doenças dos Peixes/mortalidade , Doenças dos Peixes/parasitologia , Myxozoa/genética , Doenças Parasitárias em Animais/mortalidade , Doenças Parasitárias em Animais/parasitologia , Salmonidae/parasitologia , Animais , Genótipo , Interações Hospedeiro-Parasita , Myxozoa/patogenicidade , Análise de Sobrevida
19.
Curr Pharm Biotechnol ; 13(10): 1971-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22352732

RESUMO

Rapid decontamination of the skin is the single most important action to prevent dermal absorption of chemical contaminants in persons exposed to chemical warfare agents (CWA) and toxic industrial chemicals (TICs) as a result of accidental or intentional release. Chemicals on the skin may be removed by mechanical means through the use of dry sorbents or water. Recent interest in decontamination systems which both partition contaminants away from the skin and actively neutralize the chemical has led to the development of several reactive decontamination solutions. This article will review the recently FDA-approved Reactive Skin Decontamination Lotion (RSDL) and will summarize the toxicity and efficacy studies conducted to date. Evidence of RSDL's superior performance against vesicant and organophosphorus chemical warfare agents compared to water, bleach, and dry sorbents, suggests that RSDL may have a role in mass human exposure chemical decontamination in both the military and civilian arenas.


Assuntos
Substâncias para a Guerra Química/isolamento & purificação , Descontaminação/métodos , Intoxicação/prevenção & controle , Pele/efeitos dos fármacos , Administração Cutânea , Compostos de Alumínio/administração & dosagem , Compostos de Alumínio/efeitos adversos , Compostos de Alumínio/uso terapêutico , Animais , Substâncias para a Guerra Química/farmacocinética , Substâncias para a Guerra Química/intoxicação , Reativadores da Colinesterase/administração & dosagem , Reativadores da Colinesterase/efeitos adversos , Reativadores da Colinesterase/uso terapêutico , Diacetil/administração & dosagem , Diacetil/efeitos adversos , Diacetil/análogos & derivados , Diacetil/uso terapêutico , Embalagem de Medicamentos , Humanos , Compostos de Magnésio/administração & dosagem , Compostos de Magnésio/efeitos adversos , Compostos de Magnésio/uso terapêutico , Intoxicação/mortalidade , Silicatos/administração & dosagem , Silicatos/efeitos adversos , Silicatos/uso terapêutico , Pele/metabolismo , Absorção Cutânea/efeitos dos fármacos , Creme para a Pele , Fatores de Tempo
20.
Med Phys ; 39(6Part24): 3908, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28518674

RESUMO

PURPOSE: Given the differences in tumor size and location, encountered in lung SBRT, we hypothesize that 'one dose fractionation regimen does not fit all', i.e. that there is a role for patient-specific dose prescription based on optimization of biological models. METHODS: Sixty one NSCLC patients (tumor volume 46.5+/-47.3 cc) treated with stereotactic body radiotherapy (48 Gy in 4fx) were retrospectively studied. Clinically treated plans were generated using Brainlab's Pencil Beam (PB-BL), and then recalculated with fixed MUs using Anisotropic Analytic Algorithm (AAA), Pencil Beam (PB-EC), Monte Carlo (MC) and Collapsed-Cone-Convolution (CCC). DVHs were exported to calculate TCP (Poisson) and NTCP (Lyman-Kutcher-Burman). TCP/NTCP model parameters were utilized from published data. For each dose distribution two dose response curves were generated by scaling the prescription dose and assuming a linear relationship between the prescription dose and entire 3D dose distribution. In addition, associations were assessed between changes in each algorithm's TCP relative to PB-BL, target diameter, and local density (density of the 70% isodose covering the PTV). RESULTS: For PB-BL, mean TCP was 99.6%±0.9%, whereas for same MUs, mean TCP for PB-EC, AAA, CC and MC plans were 96.5±14.3%, 74.6±31.6%, 74.4±32.4% and 76.8±32.0%, respectively. With the same prescription dose for all plans, TCP values changed to 98.1±8.7%, 96.5±15.3%, 77.5±28.6%, 85.4±25.8% and 92.9±20.1% for PB-BL, PB-EC, AAA, and CCC, MC, respectively, indicating that AAA and CCC dose distributions are likely less homogeneous relative to MC. The TCP improvement was 12.3%, 8.9% and 4.4% for AAA, CCC and MC-based plans when the average NTCP before optimization was set as the upper limit for lung toxicity. CONCLUSIONS: This work supports patient-specific dose prescription strategies, based on biological optimization, for lung SBRT. However, further investigation is warranted. Acknowledgement: supported in part by a grant from Varian Medical Systems.

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