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1.
Radiat Res ; 201(5): 487-498, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38471523

RESUMO

In gene expression (GE) studies, housekeeping genes (HKGs) are required for normalization purposes. In large-scale inter-laboratory comparison studies, significant differences in dose estimates are reported and divergent HKGs are employed by the teams. Among them, the 18S rRNA HKG is known for its robustness. However, the high abundance of 18S rRNA copy numbers requires dilution, which is time-consuming and a possible source of errors. This study was conducted to identify the most promising HKGs showing the least radiation-induced GE variance after radiation exposure. In the screening stage of this study, 35 HKGs were analyzed. This included selected HKGs (ITFG1, MRPS5, and DPM1) used in large-scale biodosimetry studies which were not covered on an additionally employed pre-designed 96-well platform comprising another 32 HKGs used for different exposures. Altogether 41 samples were examined, including 27 ex vivo X-ray irradiated blood samples (0, 0.5, 4 Gy), six X-irradiated samples (0, 0.5, 5 Gy) from two cell lines (U118, A549), as well as eight non-irradiated tissue samples to encompass multiple biological entities. In the independent validation stage, the most suitable candidate genes were examined from another 257 blood samples, taking advantage of already stored material originating from three studies. These comprise 100 blood samples from ex vivo X-ray irradiated (0-4 Gy) healthy donors, 68 blood samples from 5.8 Gy irradiated (cobalt-60) Rhesus macaques (RM) (LD29/60) collected 0-60 days postirradiation, and 89 blood samples from chemotherapy-(CTx) treated breast tumor patients. CTx and radiation-induced GE changes in previous studies appeared comparable. RNA was isolated, converted into cDNA, and GE was quantified employing TaqMan assays and quantitative RT-PCR. We calculated the standard deviation (SD) and the interquartile range (IQR) as measures of GE variance using raw cycle threshold (Ct) values and ranked the HKGs accordingly. Dose, time, age, and sex-dependent GE changes were examined employing the parametrical t-test and non-parametrical Kruskal Wallis test, as well as linear regression analysis. Generally, similar ranking results evolved using either SD or IQR GE measures of variance, indicating a tight distribution of GE values. PUM1 and PGK1 showed the lowest variance among the first ten most suitable genes in the screening phase. MRPL19 revealed low variance among the first ten most suitable genes in the screening phase only for blood and cells, but certain comparisons indicated a weak association of MRPL19 with dose (P = 0.02-0.09). In the validation phase, these results could be confirmed. Here, IQR Ct values from, e.g., X-irradiated blood samples were 0.6 raw Ct values for PUM1 and PGK1, which is considered to represent GE differences as expected due to methodological variance. Overall, when compared, the GE variance of both genes was either comparable or lower compared to 18S rRNA. Compared with the IQR GE values of PUM1 and PGKI, twofold-fivefold increased values were calculated for the biodosimetry HKG HPRT1, and comparable values were calculated for biodosimetry HKGs ITFG1, MRPS5, and DPM1. Significant dose-dependent associations were found for ITFG1 and MRPS5 (P = 0.001-0.07) and widely absent or weak (P = 0.02-0.07) for HPRT1 and DPM1. In summary, PUM1 and PGK1 appeared most promising for radiation exposure studies among the 35 HKGs examined, considering GE variance and adverse associations of GE with dose.


Assuntos
Genes Essenciais , Fosfoglicerato Quinase , Proteínas de Ligação a RNA , Exposição à Radiação , Adulto , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Relação Dose-Resposta à Radiação , Genes Essenciais/efeitos da radiação , Exposição à Radiação/efeitos adversos , Radiometria , RNA Ribossômico 18S/genética , RNA Ribossômico 18S/efeitos da radiação , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/efeitos da radiação , Macaca mulatta , Fosfoglicerato Quinase/genética , Fosfoglicerato Quinase/efeitos da radiação
2.
Radiat Res ; 201(5): 504-513, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38471521

RESUMO

Increased radiological and nuclear threats require preparedness. Our earlier work identified a set of four genes (DDB2, FDXR, POU2AF1 and WNT3), which predicts severity of the hematological acute radiation syndrome (H-ARS) within the first three days postirradiation In this study of 41 Rhesus macaques (Macaca mulatta, 27 males, 14 females) irradiated with 5.8-7.2 Gy (LD29-50/60), including some treated with gamma-tocotrienol (GT3, a radiation countermeasure) we independently validated these genes as predictors in both sexes and examined them after three days. At the Armed Forces Radiobiology Research Institute/Uniformed Services University of the Health Sciences, peripheral whole blood (1 ml) of Rhesus macaques was collected into PAXgene® Blood RNA tubes pre-irradiation after 1, 2, 3, 35 and 60 days postirradiation, stored at -80°C for internal experimental analyses. Leftover tubes from these already ongoing studies were kindly provided to Bundeswehr Institute of Radiobiology. RNA was isolated (QIAsymphony), converted into cDNA, and for further gene expression (GE) studies quantitative RT-PCR was performed. Differential gene expression (DGE) was measured relative to the pre-irradiation Rhesus macaques samples. Within the first three days postirradiation, we found similar results to human data: 1. FDXR and DDB2 were up-regulated, FDXR up to 3.5-fold, and DDB2 up to 13.5-fold in the median; 2. POU2AF1 appeared down regulated around tenfold in nearly all Rhesus macaques; 3. Contrary to human data, DDB2 was more up-regulated than FDXR, and the difference of the fold change (FC) ranged between 2.4 and 10, while the median fold changes of WNT3, except days 1 and 35, were close to 1. Nevertheless, 46% of the Rhesus macaques showed down-regulated WNT3 on day one postirradiation, which decreased to 12.2% on day 3 postirradiation. Considering the extended phase, there was a trend towards decreased fold changes at day 35, with median-fold changes ranging from 0.7 for DDB2 to 0.1 for POU2AF1, and on day 60 postirradiation, DGE in surviving animals was close to pre-exposure values for all four genes. In conclusion, the diagnostic significance for radiation-induced H-ARS severity prediction of FDXR, DDB2, and POU2AF1 was confirmed in this Rhesus macaques model. However, DDB2 showed higher GE values than FDXR. As shown in previous studies, the diagnostic significance of WNT3 could not be reproduced in Rhesus macaques; this could be due to the choice of animal model and methodological challenges.


Assuntos
Síndrome Aguda da Radiação , Macaca mulatta , Animais , Masculino , Feminino , Síndrome Aguda da Radiação/sangue , Síndrome Aguda da Radiação/genética
3.
Radiat Res ; 201(5): 384-395, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38282135

RESUMO

Radiosensitivity differs in humans and possibly in closely related nonhuman primates. The reasons for variation in radiosensitivity are not well known. In an earlier study, we examined gene expression (GE) pre-radiation in peripheral blood among male (n = 62) and female (n = 60) rhesus macaques (n = 122), which did or did not survive (up to 60 days) after whole-body exposure of 7.0 Gy (LD66/60). Eight genes (CHD5, CHI3L1, DYSF, EPX, IGF2BP1, LCN2, MBOAT4, SLC22A4) revealed significant associations with survival. Access to a second rhesus macaque cohort (males = 40, females = 23, total n = 63) irradiated with 5.8-7.2 Gy (LD29-50/60) and some treated with gamma-tocotrienol (GT3, a radiation countermeasure) allowed us to validate these gene expression changes independently. Total RNA was isolated from whole blood samples and examined by quantitative RT-PCR on a 96-well format. cycle threshold (Ct)-values normalized to 18S rRNA were analyzed for their association with survival. Regardless of the species-specific TaqMan assay, similar results were obtained. Two genes (CHD5 and CHI3L1) out of eight revealed a significant association with survival in the second cohort, while only CHD5 (involved in DNA damage response and proliferation control) showed mean gene expression changes in the same direction for both cohorts. No expected association of CHD5 GE with dose, treatment, or sex could be established. Instead, we observed significant associations for those comparisons comprising pre-exposure samples with CHD5 Ct values ≤ 11 (total n = 17). CHD5 Ct values ≤ 11 in these comparisons were mainly associated with increased frequencies (61-100%) of non-survivors, a trend which depending on the sample numbers, reached significance (P = 0.03) in males and, accordingly, in females. This was also reflected by a logistic regression model including all available samples from both cohorts comprising CHD5 measurements (n = 104, odds ratio 1.38, 95% CI 1.07-1.79, P = 0.01). However, this association was driven by males (odds ratio 1.62, 95% CI 1.10-2.38, P = 0.01) and CHD5 Ct values ≤ 11 since removing low CHD5 Ct values from this model, converted to insignificance (P = 0.19). A second male subcohort comprising high CHD5 Ct values ≥ 14.4 in both cohorts (n = 5) appeared associated with survival. Removing these high CHD5 Ct values converted the model borderline significant (P = 0.051). Based on the probability function of the receiver operating characteristics (ROC) curves, 8 (12.3%) and 5 (7.7%) from 65 pre-exposure RNA measurements in males, death and survival could be predicted with a negative and positive predictive value ranging between 85-100%. An associated odds ratio reflected a 62% elevated risk for dying or surviving per unit change (Ct-value) in gene expression, considering the before-mentioned CHD5 thresholds in RNA copy numbers. In conclusion, we identified two subsets of male animals characterized by increased (Ct values ≤ 11) and decreased (Ct values ≥ 14.4) CHD5 GE copy numbers before radiation exposure, which independently of the cohort, radiation exposure or treatment appeared to predict the death or survival in males.


Assuntos
Macaca mulatta , Tolerância a Radiação , Animais , Masculino , Feminino , Tolerância a Radiação/genética , Estudos de Coortes , Regulação da Expressão Gênica/efeitos da radiação , Relação Dose-Resposta à Radiação , Irradiação Corporal Total
4.
Talanta ; 194: 930-940, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30609627

RESUMO

The dispersion of harmful oil components into the ocean waters could pose long-term risks to flora and fauna. Due to the complexity of oil-contaminated sites, the unambiguous identification and quantitation of environmental pollutants often requires the sequence of high-performance liquid chromatography and gas chromatography-mass spectrometry. A classic example is the analysis of polycyclic aromatic hydrocarbons. This article tackles a different aspect of environmental analysis as it focuses on the Shpol'skii spectroscopy of polycyclic aromatic sulfur heterocycles, specifically those belonging to the subgroups often known as anthrathiophenes and benzonaphthothiophenes. Photoluminescence measurements were made with a commercial spectrofluorimeter equipped with a continuous wave excitation source for steady state measurements and a pulsed excitation source for time-resolved measurements in the phosphorescence time domain. To the extent of our literature search, this is the first report on the 4.2 K fluorescence and phosphorescence spectra of anthrathiophenes and benzonaphthothiophenes, and the 77 K and 4.2 K phosphorescence lifetimes of benzonaphthothiophenes. 77 K and 4.2 K analytical figures of merit revealed the possibility to detect the studied compounds at the parts-per-billion (ng mL-1) concentration levels. The spectral and lifetime data gathered in this article provides the required information to choose an appropriate photoluminescence technique for the analysis of four-ring polycyclic aromatic sulfur heterocycles in complex environmental extracts.


Assuntos
Poluentes Ambientais/análise , Poluentes Ambientais/química , Tiofenos/análise , Tiofenos/química , Limite de Detecção , Solventes/química , Espectrometria de Fluorescência , Temperatura
5.
J Steroid Biochem Mol Biol ; 187: 130-133, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30476591

RESUMO

The discovery that mutations of the CYP24A1 gene are a cause of idiopathic infantile hypercalcemia (IIH) has revived interest in measuring serum 24,25(OH)2D3. Several studies have also suggested that a high 25-hydroxyvitamin D3(25-OHD3):24,25(OH)2D3 ratio might provide additional diagnostic information in the investigation of vitamin D deficiency. Measurement of 24,25(OH)2D3 is necessarily restricted to laboratories with mass spectrometry methods although cross reactivity of the metabolite in immunoassays for 25-OHD is a potential cause of misleading results. The international External Quality Assessment (EQA) scheme for vitamin D metabolites (DEQAS) was set up in 1989. In 2013 DEQAS became an accuracy based EQA for 25-OHD with 'target values' assigned by the National Institute of Standards and Technology (NIST) Reference Measurement Procedure (RMP). A pilot scheme for serum 24,25(OH)2D3 was started in 2015 and participants were asked to measure the metabolite on each of the 5 samples sent out for 25-OHD. Inter-laboratory agreement was poor but this may reflect methodological differences, in particular different approaches to assay standardization. An important potential contribution to reducing variability among assays was the development by NIST of a 24,25(OH)2D3 RMP and its use in assigning values to SRMs 972a, 2973 and 2971, supported by the NIH Office of Dietary Supplements (ODS) as part of the Vitamin D Standardization Program (VDSP) effort.


Assuntos
Espectrometria de Massas em Tandem/métodos , Vitamina D/análogos & derivados , Vitaminas/sangue , Cromatografia Líquida/métodos , Cromatografia Líquida/normas , Humanos , Controle de Qualidade , Padrões de Referência , Espectrometria de Massas em Tandem/normas , Vitamina D/sangue
7.
J Steroid Biochem Mol Biol ; 177: 30-35, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28734989

RESUMO

Recent years have seen a substantial increase in demand for 25-hydroxyvitamin D (25-OHD) assays. DEQAS (the Vitamin D External Quality Assessment Scheme) has been monitoring the performance of these assays since 1989. The first DEQAS distribution was in June 1989 and results were submitted by 13 laboratories in the UK, two of which used HPLC/UV; the rest used ligand binding assays with a tritium tracer. Inter-laboratory CVs (ALTM) ranged from 29.3% (42.7nmol/L) to 53.7% (20.0nmol/L). Currently the scheme has participants in 56 countries using 30 methods or variants of methods. In January 2017, 918 participants returned results and inter-laboratory CVs (ALTM) ranged from 10.3% (73.1nmol/L) to 15.3% (29.4nmol/L). Over the last 27 years, there have been a number of significant milestones in assay development. The first major advance was the development of an iodinated 25-OHD tracer by Hollis and Napoli in 1992, subsequently used in an RIA kit marketed by DiaSorin. This and other commercial radioimmunoassays that followed brought 25-OHD assays within reach of many more non-specialist routine laboratories. With the introduction of fully automated non-isotopic assays without solvent extraction, measurement of 25-OHD became available to any clinical chemistry laboratory with an appropriate analytical platform. However, as the limitations of these non-extraction assays became apparent more laboratories started using LC-MS/MS methodology. Meanwhile the variable accuracy of 25-OHD methods has been addressed by the Vitamin D Standardization Program (VDSP) which encourages manufacturers to produce methods traceable to the reference measurement procedures (RMPs) of NIST, University of Ghent and the Centers for Disease Control and Prevention (CDC). DEQAS changed to an accuracy-based scheme in 2013 and now assesses assay accuracy against the NIST RMP. This review will use DEQAS results and statistics to chart the historical development in 25-OHD assay technology and highlight some of the problems encountered in obtaining reliable results for this most challenging of analytes.


Assuntos
Bioensaio/tendências , Vitamina D/análogos & derivados , Vitaminas/sangue , Bioensaio/normas , Humanos , Vitamina D/sangue
8.
Aust Dent J ; 62(4): 471-477, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28423453

RESUMO

BACKGROUND: This study aimed to assess the management and referral patterns of Victorian general dental practitioners based on periodontal diagnosis. METHODS: Following ethics approval, Victorian general dental practitioners were invited to complete five randomized text-based periodontitis scenario questionnaires. Based on their diagnosis, respondents were asked for their management options and asked to specify who would perform these treatments. Respondents were also asked about referral procedures. RESULTS: One hundred and thirty-five dentists attempted the survey. Most were in group practice and based in Melbourne. Of the total respondents, 22.5% worked in a practice employing a hygienist. The management of periodontal disease was appropriate, and treatment options increased with severity. As severity increased, patients were more likely to be referred to a periodontist. Periodontal services referred by general dentists to dental hygienists increased with the number of days the hygienists worked within a practice. Over- and underdiagnosis did not markedly affect management. The recommendation of antibiotics, mouthwashes and periodontal surgery varied depending on year and school of graduation. CONCLUSIONS: The general dentists that completed the survey are managing periodontal conditions appropriately and according to current guidelines.


Assuntos
Odontologia Geral/estatística & dados numéricos , Doenças Periodontais/diagnóstico , Doenças Periodontais/terapia , Padrões de Prática Odontológica/estatística & dados numéricos , Prática Privada/estatística & dados numéricos , Austrália , Assistência Odontológica , Higienistas Dentários , Odontólogos , Emprego , Feminino , Humanos , Masculino , Encaminhamento e Consulta , Inquéritos e Questionários
9.
Aust Dent J ; 61(2): 244-51, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26308865

RESUMO

BACKGROUND: Despite the prevalence of periodontitis in Australia, there are few reports regarding periodontal diagnosis and therapies in the general dental practice setting. This study aimed to assess the degree of diagnostic accuracy in periodontal cases of Victorian general dental practitioners. METHODS: Following ethics approval, dentists were invited to complete a scenario-based questionnaire on the Australian Dental Association Victorian Branch (ADAVB) website. Five text-based clinical scenarios (from a total of 10) were randomly presented, representing patients with a range of disease levels from periodontal health/gingivitis to severe periodontitis, and respondents were asked what examinations they would usually perform. Based upon the presented results of periodontal and radiographic examinations, a periodontal diagnosis was requested. RESULTS: One hundred and thirty-five dentists attempted the survey. Most were in group practice and based in Melbourne; 22.5% of respondents worked in a practice employing a hygienist. The clinical parameters most commonly measured to diagnose periodontal disease were pocket depth and mobility. The majority of respondents diagnosed health, gingivitis and mild periodontitis correctly compared to American Academy of Periodontology guidelines. However, moderate periodontitis tended to be diagnosed as severe. CONCLUSIONS: Dentists in Victoria used appropriate clinical parameters when assessing periodontal disease and were generally accurate in their diagnoses. There is a need for consensus regarding diagnostic definitions.


Assuntos
Odontologia Geral/normas , Doenças Periodontais/diagnóstico , Prática Privada/normas , Adulto , Feminino , Gengivite/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Periodontite/diagnóstico , Inquéritos e Questionários , Vitória
10.
Behav Neurol ; 2015: 675635, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26199458

RESUMO

BACKGROUND: Morbidly obese patients demonstrate altered olfactory acuity. There has been no study directly assessing Body Mass Index (BMI) in patients with olfactory dysfunction. Our purpose was to compare BMI in a group of patients with subjective olfactory dysfunction to those without subjective olfactory complaints. METHODS: Retrospective matched case-control study. Sixty patients who presented to a tertiary care otolaryngology center with subjective smell dysfunction over one year were identified. Neoplastic and obstructive etiologies were excluded. Demographics, BMI, and smoking status were reviewed. Sixty age, gender, and race matched control patients were selected for comparison. Chi-square testing was used. RESULTS: 48 out of 60 patients (80%) in the olfactory dysfunction group fell into the overweight or obese categories, compared to 36 out of 60 patients (60%) in the control group. There was a statistically significant difference between the olfactory dysfunction and control groups for this stratified BMI (p = 0.0168). CONCLUSION: This study suggests high BMI is associated with olfactory dysfunction. Prospective clinical research should examine this further to determine if increasing BMI may be a risk factor in olfactory loss and to elucidate what role olfactory loss may play in diet and feeding habits of obese patients.


Assuntos
Índice de Massa Corporal , Transtornos do Olfato , Sobrepeso , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Transtornos do Olfato/epidemiologia , Sobrepeso/epidemiologia , Adulto Jovem
11.
J Aquat Anim Health ; 26(1): 19-32, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24689955

RESUMO

Establishment of Myxobolus cerebralis (Mc) resulted in declines of wild Rainbow Trout Oncorhynchus mykiss populations in streams across Colorado during the 1990s. However, the risk for establishment and spread of this parasite into high-elevation habitats occupied by native Cutthroat Trout O. clarkii was unknown. Beginning in 2003, tubificid worms were collected from all major drainages where Cutthroat Trout were endemic and were assayed by quantitative PCR to determine the occurrence and distribution of the various lineages of Tubifex tubifex (Tt) oligochaetes. Over a 5-year period, 40 groups of Tt oligochaetes collected from 27 streams, 3 natural lakes, 2 private ponds, and a reservoir were evaluated for their relative susceptibility to Mc. Exposure groups were drawn from populations of pure lineage III Tt, mixed-lineage populations where one or more of the highly resistant (lineage I) or nonsusceptible lineages (V or VI) were the dominant oligochaete and susceptible lineage III worms were the subdominant worm, or pure lineage VI Tt. Experimental replicates of 250 oligochaetes were exposed to 50 Mc myxospores per worm. The parasite amplification ratio (total triactinomyxons [TAMs] produced / total myxospore exposure) was very high among all pure lineage III Colorado exposure groups, averaging 363 compared with 8.24 among the mixed-lineage exposure groups. Lineage III oligochaetes from Mt. Whitney Hatchery in California, which served as the laboratory standard for comparative purposes, had an average parasite amplification ratio of 933 among 10 exposed replicates over a 5-year period. Lineage I oligochaetes were highly resistant to infection and did not produce any TAMs. Lineages V and VI Tt did not become infected and did not produce any TAMs. These results suggest that the risk of establishment of Mc is high for aquatic habitats in Colorado where Cutthroat Trout and lineage III Tt are sympatric.


Assuntos
Reservatórios de Doenças , Myxobolus/fisiologia , Oligoquetos/parasitologia , Truta , Animais , Colorado , Predisposição Genética para Doença , Interações Hospedeiro-Parasita , Oligoquetos/genética , RNA Ribossômico 16S/genética , Movimentos da Água
12.
Anal Bioanal Chem ; 405(13): 4437-41, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23552970

RESUMO

The National Institute of Standards and Technology administers quality assurance programs devoted to improving measurements of nutrients and related metabolites in foods, dietary supplements, and serum and plasma samples. These programs have been developed in collaboration with the National Institutes of Health to assist measurement communities in their efforts to achieve accurate results that are comparable among different laboratories and over time. Targeted analytes include micronutrients, botanical markers, nutritional elements, contaminants, fatty acids, and vitamin D metabolites.


Assuntos
Suplementos Nutricionais/análise , Ácidos Graxos/sangue , Análise de Alimentos/normas , Micronutrientes/sangue , Suplementos Nutricionais/normas , Ácidos Graxos/normas , Análise de Alimentos/métodos , Humanos , Micronutrientes/normas , National Institutes of Health (U.S.) , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos
13.
Oncogene ; 32(12): 1549-59, 2013 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22641218

RESUMO

Transforming growth factor-beta (TGF-ß) has a dual role in epithelial malignancies, including head and neck squamous cell carcinoma (HNSCC). Attenuation of canonical TGF-ß signaling enhances de novo tumor development, whereas TGF-ß overexpression and signaling paradoxically promotes malignant progression. We recently observed that TGF-ß-induced growth arrest response is attenuated, in association with aberrant activation of nuclear factor-κB (NF-κB), a transcription factor, which promotes malignant progression in HNSCC. However, what role cross-talk between components of the TGF-ß and NF-κB pathways plays in altered activation of these pathways has not been established. Here, we show TGF-ß receptor II and TGF-ß-activated kinase 1 (TAK1) are predominantly expressed in a subset of HNSCC tumors with nuclear activation of NF-κB family member RELA (p65). Further, TGF-ß1 treatment induced sequential phosphorylation of TAK1, IKK, IκBα and RELA in human HNSCC lines. TAK1 enhances TGF-ß-induced NF-κB activation, as TAK1 siRNA knockdown decreased TGF-ß1-induced phosphorylation of IKK, IκB and RELA, degradation of IκBα, RELA nuclear translocation and DNA binding, and NF-κB-induced reporter and target gene transcription. Functionally, TAK1 siRNA inhibited cell proliferation, migration and invasion. Celastrol, a TAK1 inhibitor and anti-inflammatory compound used in traditional Chinese medicine, also decreased TGF-ß1-induced phosphorylation of TAK1 and RELA, and suppressed basal, TGF-ß1- and tumor necrosis factor-alpha (TNF-α)-induced NF-κB reporter gene activity. Celastrol also inhibited cell proliferation, while increasing sub-G0 DNA fragmentation and Annexin V markers of apoptosis. Furthermore, TGF-ß and RELA activation promoted SMAD7 expression. In turn, SMAD7 preferentially suppressed TGF-ß-induced SMAD and NF-κB reporters when compared with constitutive or TNF-α-induced NF-κB reporter gene activation. Thus, cross-talk by TGF-ß via TAK1 and NF-κB promotes the malignant phenotype of HNSCC. Moreover, NF-κB may contribute to the downstream attenuation of canonical TGF-ß signaling through increased SMAD7 expression. Celastrol highlights the therapeutic potential of agents targeting TAK1 as a key node in this pro-oncogenic TGF-ß-NF-κB signal pathway.


Assuntos
Carcinoma de Células Escamosas/etiologia , Neoplasias de Cabeça e Pescoço/etiologia , MAP Quinase Quinase Quinases/fisiologia , NF-kappa B/fisiologia , Transdução de Sinais/fisiologia , Proteína Smad7/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Invasividade Neoplásica , Carcinoma de Células Escamosas de Cabeça e Pescoço , Fator de Transcrição RelA/fisiologia
14.
Leukemia ; 27(2): 278-85, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22907049

RESUMO

Activating mutations in the receptor tyrosine kinase KIT, most notably KIT D816V, are commonly observed in patients with systemic mastocytosis. Thus, inhibition of KIT has been a major focus for treatment of this disorder. Here we investigated a novel approach to such inhibition. Utilizing rational drug design, we targeted the switch pocket (SP) of KIT, which regulates its catalytic conformation. Two SP inhibitors thus identified, DP-2976 and DP-4851, were examined for effects on neoplastic mast cell proliferation and mast cell activation. Autophosphorylation of both wild-type and, where also examined, KIT D816V activation was blocked by these compounds in transfected 293T cells, HMC 1.1 and 1.2 human mast cell lines, and in CD34(+)-derived human mast cells activated by stem cell factor (SCF). Both inhibitors induced apoptosis in the neoplastic mast cell lines and reduced survival of primary bone marrow mast cells from patients with mastocytosis. Moreover, the SP inhibitors more selectively blocked SCF potentiation of FcɛRI-mediated degranulation. Overall, SP inhibitors represent an innovative mechanism of KIT inhibition whose dual suppression of KIT D816V neoplastic mast cell proliferation and SCF-enhanced mast cell activation may provide significant therapeutic benefits.


Assuntos
Proliferação de Células , Mastócitos/metabolismo , Mastocitose Sistêmica/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-kit/antagonistas & inibidores , Animais , Humanos , Mastócitos/patologia
15.
Hum Reprod ; 28(2): 375-84, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23178271

RESUMO

STUDY QUESTION: How do families with children conceived using donor sperm operate as the children grow up? SUMMARY ANSWER: Families with children aged 5-13 years conceived through anonymous donor sperm function well, when compared with other family types with children of the same developmental stage. WHAT IS KNOWN ALREADY: Previous studies on family relationships after donor sperm conception have been reassuring. However, these studies have suffered from methodological limitations due to small sample sizes, respondent biases and absence of appropriate controls. STUDY DESIGN, SIZE, DURATION: This study was an observational study comparing 79 'donor insemination' (DI) families with 987 'couple' families, 364 'single mother' and 112 'step-father' families as part of the Australian Institute of Family Studies Children and Family Life (CFL) study. CFL involved the collection of data on family functioning and child wellbeing from all resident parents through a Family and Child Questionnaire for the 'primary' parent (FACQ-P1) and a Family Relationship Questionnaire (FRQ-P2) for the 'other' parent. PARTICIPANTS/MATERIALS, SETTING, METHODS: All questionnaires were coded with the identity known only to the researchers. The outcomes studied included parent psychological adjustment, family functioning, couple relationship, parenting and parent-child relationship. Family types were compared, separately for mothers' and fathers' reports. The results presented are the estimated means for each family type based on the final model for each outcome: post hoc comparisons between family types are reported with 95% confidence limits. MAIN RESULTS AND THE ROLE OF CHANCE: With all of the outcomes considered, there was not one result where the DI families showed poorer functioning on average than the comparison groups. LIMITATIONS, REASON FOR CAUTION: The final sample size of DI families is 79 with an excellent response rate of nearly 80%. However, there remains some scope for response bias. WIDER IMPLICATIONS OF THE FINDINGS: This study further reassures us that families conceived with anonymous donor sperm do not function any differently from other family types.


Assuntos
Família/psicologia , Inseminação Artificial Heteróloga/psicologia , Relações Pais-Filho , Adolescente , Adulto , Criança , Pré-Escolar , Características da Família , Feminino , Humanos , Masculino
16.
Anal Bioanal Chem ; 402(1): 473-87, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22127575

RESUMO

A suite of three green tea-containing Standard Reference Materials (SRMs) has been issued by the National Institute of Standards and Technology (NIST): SRM 3254 Camellia sinensis (Green Tea) Leaves, SRM 3255 Camellia sinensis (Green Tea) Extract, and SRM 3256 Green Tea-Containing Solid Oral Dosage Form. The materials are characterized for catechins, xanthine alkaloids, theanine, and toxic elements. As many as five methods were used in assigning certified and reference values to the constituents, with measurements carried out at NIST and at collaborating laboratories. The materials are intended for use in the development and validation of new analytical methods, and for use as control materials as a component in the support of claims of metrological traceability.


Assuntos
Camellia sinensis/química , Análise de Alimentos/normas , Chá/química , Análise de Alimentos/métodos , Padrões de Referência
17.
Immunohematology ; 28(4): 118-23, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23421540

RESUMO

A 15-month-old white male child was admitted to the pediatric intensive care unit with symptoms of upper respiratory tract infection, increased somnolence, pallor, jaundice, fever, and decreased activity level. The purpose of this case study is to report the clinical findings associated with the patient's clinical symptoms and differential laboratory diagnosis.


Assuntos
Hemoglobinúria Paroxística/diagnóstico , Diagnóstico Diferencial , Febre/complicações , Febre/diagnóstico , Febre/fisiopatologia , Hemoglobinúria Paroxística/complicações , Hemoglobinúria Paroxística/fisiopatologia , Humanos , Lactente , Unidades de Terapia Intensiva , Icterícia/complicações , Icterícia/diagnóstico , Icterícia/fisiopatologia , Masculino , Infecções Respiratórias/complicações , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/fisiopatologia
18.
Anal Chem ; 83(1): 99-108, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21128589

RESUMO

A new multivitamin/multielement dietary supplement Standard Reference Material (SRM) has been issued by the National Institute of Standards and Technology (NIST), with certified and reference concentration values for 13 vitamins, 24 elements, and 2 carotenoids. The constituents have been measured by multiple analytical methods with data contributed by NIST and by collaborating laboratories. This effort included the first use of isotope dilution mass spectrometry for value assignment of both fat-soluble vitamins (FSVs) and water-soluble vitamins (WSVs). Excellent agreement was obtained among the methods, with relative expanded uncertainties for the certified concentration values typically ranging from <2% to 15% for vitamins.


Assuntos
Carotenoides/normas , Suplementos Nutricionais/análise , Suplementos Nutricionais/normas , Vitaminas/normas , Carotenoides/análise , Carotenoides/química , Carotenoides/isolamento & purificação , Controle de Qualidade , Padrões de Referência , Comprimidos , Vitaminas/análise , Vitaminas/química , Vitaminas/isolamento & purificação
19.
Oncogene ; 30(14): 1643-52, 2011 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-21132014

RESUMO

Mesothelioma is an asbestos-associated and notoriously chemotherapy-resistant neoplasm. Activation of the receptor tyrosine kinases (RTKs), epidermal growth factor receptor and MET, has been described in subsets of mesothelioma, suggesting that TKs might represent therapeutic targets in this highly lethal disease. We employed proteomic screening by phosphotyrosine immunoaffinity purification and tandem mass spectrometry to characterize RTK activation in mesothelioma cell lines. These assays demonstrated expression and activation of the AXL protein, which is an RTK with known oncogenic properties in non-mesothelial cancer types. AXL was expressed and activated strongly in 8 of 9 mesothelioma cell lines and 6 of 12 mesothelioma biopsies, including each of 12 mesotheliomas with spindle-cell histology. Somatic AXL mutations were not found, but all mesotheliomas expressed an alternatively spliced AXL transcript with in-frame deletion of exon 10, and six of seven mesothelioma cell lines expressed the AXL ligand, growth arrest-specific 6 (GAS6). GAS6 expression appeared to be functionally relevant, as indicated by modulation of AXL tyrosine phosphorylation by knockdown of endogeneous GAS6, and by administration of exogenous GAS6. AXL silencing by lentivirus-mediated short hairpin RNA suppressed mesothelioma migration and cellular proliferation due to G1 arrest. The AXL inhibitor DP-3975 inhibited cell migration and proliferation in mesotheliomas with strong AXL activation. DP-3975 response in these tumors was characterized by inhibition of PI3-K/AKT/mTOR and RAF/MAPK signaling. AXL inhibition suppressed mesothelioma anchorage-independent growth, with reduction in colony numbers and size. These studies suggest that AXL inhibitors warrant clinical evaluation in mesothelioma.


Assuntos
Proliferação de Células/efeitos dos fármacos , Mesotelioma/genética , Neoplasias Pleurais/genética , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/genética , Processamento Alternativo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Éxons , Inativação Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/isolamento & purificação , Mesotelioma/tratamento farmacológico , Mesotelioma/patologia , Invasividade Neoplásica/genética , Fosforilação , Neoplasias Pleurais/tratamento farmacológico , Neoplasias Pleurais/patologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/metabolismo , Deleção de Sequência , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Receptor Tirosina Quinase Axl
20.
Math Comput Model ; 53(1-2): 1-20, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21076663

RESUMO

In this paper we give the details of the numerical solution of a three-dimensional multispecies diffuse interface model of tumor growth, which was derived in (Wise et al., J. Theor. Biol. 253 (2008)) and used to study the development of glioma in (Frieboes et al., NeuroImage 37 (2007) and tumor invasion in (Bearer et al., Cancer Research, 69 (2009)) and (Frieboes et al., J. Theor. Biol. 264 (2010)). The model has a thermodynamic basis, is related to recently developed mixture models, and is capable of providing a detailed description of tumor progression. It utilizes a diffuse interface approach, whereby sharp tumor boundaries are replaced by narrow transition layers that arise due to differential adhesive forces among the cell-species. The model consists of fourth-order nonlinear advection-reaction-diffusion equations (of Cahn-Hilliard-type) for the cell-species coupled with reaction-diffusion equations for the substrate components. Numerical solution of the model is challenging because the equations are coupled, highly nonlinear, and numerically stiff. In this paper we describe a fully adaptive, nonlinear multigrid/finite difference method for efficiently solving the equations. We demonstrate the convergence of the algorithm and we present simulations of tumor growth in 2D and 3D that demonstrate the capabilities of the algorithm in accurately and efficiently simulating the progression of tumors with complex morphologies.

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