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1.
Sensors (Basel) ; 23(4)2023 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-36850895

RESUMO

With the development of mobile communications and the Internet of Things (IoT), IoT devices have increased, allowing their application in numerous areas of Industry 4.0. Applications on IoT devices are time sensitive and require a low response time, making reducing latency in IoT networks an essential task. However, it needs to be emphasized that data production and consumption are interdependent, so when designing the implementation of a fog network, it is crucial to consider criteria other than latency. Defining the strategy to deploy these nodes based on different criteria and sub-criteria is a challenging optimization problem, as the amount of possibilities is immense. This work aims to simulate a hybrid network of sensors related to public transport in the city of São Carlos - SP using Contiki-NG to select the most suitable place to deploy an IoT sensor network. Performance tests were carried out on five analyzed scenarios, and we collected the transmitted data based on criteria corresponding to devices, applications, and network communication on which we applied Multiple Attribute Decision Making (MADM) algorithms to generate a multicriteria decision ranking. The results show that based on the TOPSIS and VIKOR decision-making algorithms, scenario four is the most viable among those analyzed. This approach makes it feasible to optimally select the best option among different possibilities.

2.
Arch Gynecol Obstet ; 292(6): 1273-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25990479

RESUMO

PURPOSE: To investigate the prevalence of human papillomavirus (HPV) in cervical samples of pregnant and non-pregnant women in South-Brazil. METHODS: A prospective study of 91 pregnant and 92 non-pregnant women with no previous history of cervical dysplasia or cancer was carried out. Cervical samples for HPV testing and cytology were collected in each trimester of pregnancy and in the puerperium for pregnant women and at matched intervals for the non-pregnant women. All samples were analyzed through PCR with consensus primers GP5+/GP6+. Genotyping was performed using specific primers. To control for confounding factors, the analysis of multivariate logistic regression was applied. The measure of odds ratio (OR) and the 95 % confidence interval (95 % CI) were used. The level of statistical significance was set at 5 % (P ≤ 0.05). RESULTS: HPV DNA was detected in 23/91 (25.3 %) cervical samples from the pregnant women and in 12/92 (13 %) cervical samples from non-pregnant women (P = 0.035). There was a significant association among cervical HPV infection and young age, number of lifetime sexual partners, and the presence of abnormal cervical cytology. HPV16 and HPV18 were the viral types more frequently detected. Out of the 23 HPV-positive pregnant women, 17 (73.9 %) had normal cervical cytology. CONCLUSION: Our results suggest a higher prevalence of HPV infection in pregnant vs. non-pregnant women. This finding may be related to the relative immunosuppression observed in pregnant women, outlining the importance of the appropriate monitoring of the viral infection in this specific population.


Assuntos
DNA Viral/análise , Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Adulto , Brasil/epidemiologia , Feminino , Genótipo , Papillomavirus Humano 16/genética , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Análise Multivariada , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/genética , Reação em Cadeia da Polimerase , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Gestantes , Prevalência , Estudos Prospectivos , Esfregaço Vaginal , Adulto Jovem
3.
Evol Comput ; 23(1): 1-36, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24437665

RESUMO

Structured evolutionary algorithms have been investigated for some time. However, they have been under explored especially in the field of multi-objective optimization. Despite good results, the use of complex dynamics and structures keep the understanding and adoption rate of structured evolutionary algorithms low. Here, we propose a general subpopulation framework that has the capability of integrating optimization algorithms without restrictions as well as aiding the design of structured algorithms. The proposed framework is capable of generalizing most of the structured evolutionary algorithms, such as cellular algorithms, island models, spatial predator-prey, and restricted mating based algorithms. Moreover, we propose two algorithms based on the general subpopulation framework, demonstrating that with the simple addition of a number of single-objective differential evolution algorithms for each objective, the results improve greatly, even when the combined algorithms behave poorly when evaluated alone at the tests. Most importantly, the comparison between the subpopulation algorithms and their related panmictic algorithms suggests that the competition between different strategies inside one population can have deleterious consequences for an algorithm and reveals a strong benefit of using the subpopulation framework.


Assuntos
Algoritmos , Metodologias Computacionais , Modelos Teóricos , Simulação por Computador
4.
Animals (Basel) ; 14(14)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39061485

RESUMO

Mastitis, an important disease in dairy cows, causes significant losses in herd profitability. Accurate diagnosis is crucial for adequate control. Studies using artificial intelligence (AI) models to classify, identify, predict, and diagnose mastitis show promise in improving mastitis control. This bibliometric review aimed to evaluate AI and bovine mastitis terms in the most relevant Scopus-indexed papers from 2011 to 2021. Sixty-two documents were analyzed, revealing key terms, prominent researchers, relevant publications, main themes, and keyword clusters. "Mastitis" and "machine learning" were the most cited terms, with an increasing trend from 2018 to 2021. Other terms, such as "sensors" and "mastitis detection", also emerged. The United States was the most cited country and presented the largest collaboration network. Publications on mastitis and AI models notably increased from 2016 to 2021, indicating growing interest. However, few studies utilized AI for bovine mastitis detection, primarily employing artificial neural network models. This suggests a clear potential for further research in this area.

5.
Sci Rep ; 14(1): 7186, 2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38531913

RESUMO

Tinnitus is a conscious attended awareness perception of sourceless sound. Widespread theoretical and evidence-based neurofunctional and psychological models have tried to explain tinnitus-related distress considering the influence of psychological and cognitive factors. However, tinnitus models seem to be less focused on causality, thereby easily misleading interpretations. Also, they may be incapable of individualization. This study proposes a Conceptual Cognitive Framework (CCF) providing insight into cognitive mechanisms involved in the predisposition, precipitation, and perpetuation of tinnitus and consequent cognitive-emotional disturbances. The current CCF for tinnitus relies on evaluative conditional learning and appraisal, generating negative valence (emotional value) and arousal (cognitive value) to annoyance, distress, and distorted perception. The suggested methodology is well-defined, reproducible, and accessible, which can help foster future high-quality clinical databases. Perceived tinnitus through the perpetual-learning process can always lead to annoyance, but only in the clinical stage directly cause annoyance. In the clinical stage, tinnitus perception can lead indirectly to distress only with experiencing annoyance either with (" I n d - 1 C " = 1.87; 95% CI 1.18-2.72)["1st indirect path in the Clinical stage model": Tinnitus Loudness → Attention Bias → Cognitive-Emotional Value → Annoyance → Clinical Distress]or without (" I n d - 2 C "= 2.03; 95% CI 1.02-3.32)[ "2nd indirect path in the Clinical stage model": Tinnitus Loudness → Annoyance → Clinical Distress] the perpetual-learning process. Further real-life testing of the CCF is expected to express a meticulous, decision-supporting platform for cognitive rehabilitation and clinical interventions. Furthermore, the suggested methodology offers a reliable platform for CCF development in other cognitive impairments and supports the causal clinical data models. It may also enhance our knowledge of psychological disorders and complicated comorbidities by supporting the design of different rehabilitation interventions and comprehensive frameworks in line with the "preventive medicine" policy.


Assuntos
Zumbido , Humanos , Emoções , Cognição , Sintomas Afetivos , Nível de Alerta
6.
J Comput Chem ; 34(20): 1719-34, 2013 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-23666867

RESUMO

This article focuses on the development of an approach for ab initio protein structure prediction (PSP) without using any earlier knowledge from similar protein structures, as fragment-based statistics or inference of secondary structures. Such an approach is called purely ab initio prediction. The article shows that well-designed multiobjective evolutionary algorithms can predict relevant protein structures in a purely ab initio way. One challenge for purely ab initio PSP is the prediction of structures with ß-sheets. To work with such proteins, this research has also developed procedures to efficiently estimate hydrogen bond and solvation contribution energies. Considering van der Waals, electrostatic, hydrogen bond, and solvation contribution energies, the PSP is a problem with four energetic terms to be minimized. Each interaction energy term can be considered an objective of an optimization method. Combinatorial problems with four objectives have been considered too complex for the available multiobjective optimization (MOO) methods. The proposed approach, called "Multiobjective evolutionary algorithms with many tables" (MEAMT), can efficiently deal with four objectives through the combination thereof, performing a more adequate sampling of the objective space. Therefore, this method can better map the promising regions in this space, predicting structures in a purely ab initio way. In other words, MEAMT is an efficient optimization method for MOO, which explores simultaneously the search space as well as the objective space. MEAMT can predict structures with one or two domains with RMSDs comparable to values obtained by recently developed ab initio methods (GAPFCG , I-PAES, and Quark) that use different levels of earlier knowledge.


Assuntos
Algoritmos , Biologia Computacional , Simulação por Computador , Proteínas/química , Ligação de Hidrogênio , Modelos Moleculares , Conformação Proteica , Eletricidade Estática
7.
Front Neurosci ; 15: 628836, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34366767

RESUMO

Insomnia is a widespread neuropsychological sleep-related disorder known to result in various predicaments including cognitive impairments, emotional distress, negative thoughts, and perceived sleep insufficiency besides affecting the incidence and aggravation of other medical disorders. Despite the available insomnia-related theoretical cognitive models, clinical studies, and related guidelines, an evidence-based conceptual framework for a personalized approach to insomnia seems to be lacking. This study proposes a conceptual cognitive framework (CCF) providing insight into cognitive mechanisms involved in the predisposition, precipitation, and perpetuation of insomnia and consequent cognitive deficits. The current CCF for insomnia relies on evaluative conditional learning and appraisal which generates negative valence (emotional value) and arousal (cognitive value). Even with the limitations of this study, the suggested methodology is well-defined, reproducible, and accessible can help foster future high-quality clinical databases. During clinical insomnia but not the neutral one, negative mood (trait-anxiety) causes cognitive impairments only if mediating with a distorted perception of insomnia ( Ind-1 = 0.161, 95% CI 0.040-0.311). Further real-life testing of the CCF is intended to formulate a meticulous, decision-supporting platform for clinical interventions. Furthermore, the suggested methodology is expected to offer a reliable platform for CCF-development in other cognitive impairments and support the causal clinical data models. It may also improve our knowledge of psychological disturbances and complex comorbidities to help design rehabilitation interventions and comprehensive frameworks in line with the "preventive medicine" policies.

9.
Heliyon ; 4(7): e00690, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30073212

RESUMO

Science Gateways have been widely accepted as an important tool in academic research, due to their flexibility, simple use and extension. However, such systems may yield performance traps that delay work progress and cause waste of resources or generation of poor scientific results. This paper addresses an investigation on some of the failures in a Galaxy system and analyses of their impacts. The use case is based on protein structure prediction experiments performed. A novel science gateway component is proposed towards the definition of the relation between general parameters and capacity of machines. The machine-learning strategies used appoint the best machine setup in a heterogeneous environment and the results show a complete overview of Galaxy, a diverse platform organization, and the workload behavior. A Support Vector Regression (SVR) model generated and based on a historic data-set provided an excellent learning module and proved a varied platform configuration is valuable as infrastructure in a science gateway. The results revealed the advantages of investing in local cluster infrastructures as a base for scientific experiments.

10.
Arq Gastroenterol ; 44(1): 58-63, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17639185

RESUMO

BACKGROUND: The prevalence and consequences of occult HBV infection in patients with chronic liver disease by HCV remain unknown. AIMS: To evaluate the prevalence of occult HBV infection in a population of HCV-infected patients with hepatocellular carcinoma. METHODS: The serum samples were tested for HBV DNA by nested PCR and liver tissue analysis was carried out using the immunohistochemical technique of 66 HBsAg-negative patients: 26 patients with chronic hepatitis by HCV (group 1), 20 with hepatocellular carcinoma related to chronic infection by HCV (group 2) and 20 with negative viral markers for hepatitis B and C (control group). RESULTS: Occult HBV infection was diagnosed in the liver tissue of 9/46 (19.5%) HCV-infected patients. Prevalence of occult B infection was evaluated in the HCV-infected patients with and without hepatocellular carcinoma, and there were seven (77.7%) of whom from group 2, conferring a 35% prevalence of this group. No serum sample was positive for HBV DNA in the three groups. CONCLUSION: Occult infection B is frequently detected in liver tissue of HCV-infected patients, especially in cases of hepatocellular carcinoma. However large studies are needed to confirm that co-infection could determine a worse progress of chronic liver disease in this population.


Assuntos
Carcinoma Hepatocelular/complicações , Hepatite B/complicações , Hepatite C/complicações , Neoplasias Hepáticas/complicações , Brasil , Estudos de Casos e Controles , DNA Viral/análise , Feminino , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Arq Gastroenterol ; 43(3): 224-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17160239

RESUMO

BACKGROUND: Nonalcoholic steatohepatitis is a chronic liver disease with a high prevalence in the general population and a potential to evolve into cirrhosis. It is speculated that iron overload could be associated with liver injury and unfavorable progress in affected patients. AIMS: To evaluate the prevalence of mutation of the hemochromatosis gene (HFE) in patients with nonalcoholic steatohepatitis and to correlate it with histological findings in liver specimens. PATIENTS AND METHODS: Twenty-nine patients with nonalcoholic steatohepatitis were evaluated. The presence of mutation in the hemochromatosis gene (C282Y and H63D) was tested in all patients and its result was evaluated in relation to hepatic inflammatory activity, presence of fibrosis, and iron overload in the liver. The control group was composed of 20 patients with normal liver function tests and 20 patients infected with the hepatitis C virus, with elevated serum levels of aminotransferases and with chronic hepatitis as shown by biopsy. RESULTS: Mutation of the hemochromatosis gene (C282Y and/or H63D) was diagnosed in 16 (55.2%) patients with nonalcoholic steatohepatitis, in 12 (60%) patients with hepatitis C and in 8 (40%) patients with no liver disease. No association was found between the presence of mutation and inflammatory activity, nor with the presence of fibrosis in patients with nonalcoholic steatohepatitis. An association was found between the presence of mutation and the occurrence of iron overload in liver, but there was no association between liver iron and the occurrence of fibrosis. CONCLUSIONS: The findings suggest that iron does not play a major role in the pathogenesis and progression of nonalcoholic steatohepatitis, and routine tests of the hemochromatosis gene mutation in these patients should not be recommended.


Assuntos
Fígado Gorduroso/genética , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Cirrose Hepática/patologia , Proteínas de Membrana/genética , Mutação , Adulto , Estudos de Casos e Controles , Fígado Gorduroso/patologia , Feminino , Ferritinas/sangue , Proteína da Hemocromatose , Humanos , Ferro/sangue , Cirrose Hepática/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Transferrina/análise
12.
Pathol Oncol Res ; 11(2): 114-20, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15999157

RESUMO

To estimate the association between human papillomavirus (HPV) status and the expression of p53, Ki-67 and bcl-2 in cases of endocervical adenocarcinoma, and the relation with squamous intraepithelial lesions (SIL) and age, 229 cases were selected, treated between 1995 and 2003 in the Hospital Nossa Senhora da Conceiçao. All samples were evaluated by polymerase chain reaction to determine HPV status. Immunohistochemical technique was used to investigate the expression of p53, Ki-67 and bcl-2. The joint occurrence of endocervical adenocarcinoma and SIL were estimated too. In the 229 evaluated cases, 182 cases (79.48%) were associated with the presence of the HPV. The most common types were HPV18 (93 cases - 51.09%) and HPV16 (62 cases - 34.06%). Expression of Ki-67 (p=0.009) and the presence of SIL (p=0.018) were associated to HPV infection. Expression of p53 (p=0.647) and bcl-2 (p=0.671) were not related to HPV status. The mean age of the patients was 53.2 years, without clear correlation between age group and HPV (p=0.095). The presence of HPV, especially type 18 in endocervical adenocarcinoma suggests that this agent can be an important cofactor in the development and progression of glandular neoplasms of the uterine cervix. The joint occurrence of endocervical adenocarcinoma and SIL may support this hypothesis. HPV may promote an increased proliferation index in endocervical adenocarcinoma, shown by the expression of Ki-67.


Assuntos
Adenocarcinoma/virologia , Antígeno Ki-67/metabolismo , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/patologia , Neoplasias do Colo do Útero/virologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Proliferação de Células , Colo do Útero/metabolismo , Colo do Útero/patologia , Colo do Útero/virologia , DNA Viral/análise , Feminino , Humanos , Pessoa de Meia-Idade , Papillomaviridae/classificação , Infecções por Papillomavirus/virologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/metabolismo , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
13.
Arq Gastroenterol ; 41(2): 84-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15543379

RESUMO

BACKGROUND: There still are controversies concerning the vertical transmission of hepatitis C virus. AIM: To evaluate the prevalence of antibodies against hepatitis C virus in pregnant women, as well as the rate of vertical transmission of this virus. PATIENTS AND METHODS: Between August 1998 and November 1999, 1,090 consecutive pregnant women were screened for anti-hepatitis C virus; positive results were confirmed by the polymerase chain reaction assay. Patient's viral load was evaluated by the branched deoxyribonucleic acid assay. Hepatitis C virus genotype was identified by direct sequencing of the polymerase chain reaction amplification products. The same tests were performed in the children born from infected mothers at the 1st and 6th month of life. RESULTS: Of the 1,090 mothers surveyed, 29 were positive for anti-hepatitis C virus (prevalence of 2.66%). Twenty-five patients presented with hepatitis C virus RNA, with a median hepatitis C virus viral load of 3.132 +/- 5.891 MEq/mL. Twenty-two patients (six human immunodeficiency virus-coinfected) were followed and gave birth to 23 children; 18 of them had blood samples tested at the 1st month of life, and 22, at the 6th month. Vertical transmission rate was 5.56%; it affected a girl who had hepatitis C virus RNA detectable only in the 1st month sample (41.570 MEq/mL). The mother who transmitted hepatitis C virus was coinfected with human immunodeficiency virus and presented with an hepatitis C virus viral load of 3.765 MEq/mL, with 100% homology with her daughter's hepatitis C virus genotype. CONCLUSION: These results suggest that the prevalence of hepatitis C virus infection in pregnant women should not be neglected, and early diagnosis of vertical transmission and the follow up of infected children should be emphasized.


Assuntos
Anticorpos Anti-Hepatite C/sangue , Hepatite C/transmissão , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Complicações Infecciosas na Gravidez/sangue , Adolescente , Adulto , Brasil/epidemiologia , Feminino , Seguimentos , Soropositividade para HIV/sangue , Hepatite C/sangue , Hepatite C/epidemiologia , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/virologia , RNA Viral/sangue , Estatísticas não Paramétricas , Carga Viral
14.
Arq Gastroenterol ; 41(3): 180-4, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15678203

RESUMO

BACKGROUND: Considering the immunosuppression of patients with chronic liver disease, their response to vaccination is discussed in literature. AIMS: To evaluate the response of hepatitis B vaccine in patients with chronic hepatitis C virus infection. METHODS: This is a prospective study in which 85 patients with chronic hepatitis C virus infection (46.8 +/- 9.4 years, 44.7% males) and 46 healthy adults (36.7 +/- 11.1 years; 39.1% males) were evaluated. Confirmation of hepatitis C virus was obtained by the technique of polymerase chain reaction. Viral load was determined by the branched DNA method in 74 patients, and genotype was determined by sequencing in 73 patients. All patients and healthy adults received three doses of Engerix B vaccine IM (at 0, 30 and 180 days). Serological responses to the vaccine were divided into three categories: seroprotection, when anti-HBs was > or =100 mUI/mL; seroconversion, when anti-HBs was 10-99 mUI/mL, and non-reagent, when anti-HBs was <10 mUI/mL. RESULTS: The response of hepatitis B vaccine as determined 1 month following dose 3 was seroprotection in 37.7%, seroconversion in 17.6% and non-reagent in 44.7% among patients and 84.8%, 13.0%, 2.2%, respectively in healthy adults. The number of non-reagent responses was significantly higher among those patients with chronic liver disease. Sixty-five patients with chronic hepatitis were compared to 20 compensated cirrhotic patients in concern to the response to vaccine, but no difference was found. The response to vaccine in patients with genotypes 2 or 3 (n = 40) was better than in those with genotype 1 (n = 33). Response was not related to serum HCV-RNA concentration. CONCLUSION: The number of non-responders was higher in patients with chronic hepatitis C virus infection, irrespective of histological status and viral load. It is suggested that such patients should receive a double dose of vaccine, particularly the ones with genotype 1.


Assuntos
Vacinas contra Hepatite B/imunologia , Hepatite C Crônica/imunologia , Adulto , Idoso , Doença Crônica , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite B/prevenção & controle , Vacinas contra Hepatite B/administração & dosagem , Hepatite C Crônica/genética , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Carga Viral
15.
Pathol Oncol Res ; 17(4): 867-72, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21461979

RESUMO

TWIST1 gene, a transcription factor that belongs to the family of basic helix-loop-helix proteins, has been related to tumor progression and metastasis in different cancers. The aim of our study was to investigate TWIST1 promoter methylation in patients with primary colorectal carcinoma and determine its correlation with prognostic factors and disease outcome. Seventy-three patients with primary colorectal adenocarcinoma were studied. From each patient two tissue samples were collected: one sample of the tumor and one sample of normal colorectal tissue from an area located 15 cm away from the tumor. Samples of colorectal mucosa obtained from 30 individuals without malignant disease were also studied as a control group. All tissues were analyzed through methylation-specific PCR. TWIST1 hypermethylation was detected in colorectal specimens of 46 patients with cancer, but in none of the tissues from the nonmalignant control group (p < 0.001). In cancer patients, TWIST1 hypermethylation was found in 38 of 73 tumor samples as compared with 20 of 73 matched samples of non-cancerous colorectal tissue (P = 0.001). TWIST1 hypermethylation was not correlated with prognostic predictors for the disease outcome, patients' overall survival and disease-free survival rates. We concluded that TWIST1 hypermethylation is present in the colon and rectum of most patients with colorectal carcinoma, suggesting this molecular alteration may be involved in the process of colorectal carcinogenesis.


Assuntos
Carcinoma/genética , Neoplasias Colorretais/genética , Metilação de DNA , Proteínas Nucleares/genética , Proteína 1 Relacionada a Twist/genética , Adulto , Idoso , Estudos de Casos e Controles , Neoplasias Colorretais/metabolismo , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Mucosa Intestinal/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/metabolismo , Prognóstico , Regiões Promotoras Genéticas , Proteína 1 Relacionada a Twist/metabolismo
16.
Braz J Infect Dis ; 14(2): 170-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20563444

RESUMO

INTRODUCTION: BKV nephropathy (BKN) causes kidney graft loss, whose specific diagnosis is invasive and might be predicted by the early detection of active viral infection. OBJECTIVE: Determine the BKV-infection prevalence in late kidney graft dysfunction by urinary decoy cell (DC) and viral DNA detection in urine (viruria) and blood (viremia; active infection). METHODS: Kidney recipients with >1 month follow-up and creatinine >1.5 mg/dL and/or recent increasing >20% (n = 120) had their urine and blood tested for BKV by semi-nested PCR, DC searching, and graft biopsy. PCR-positive patients were classified as 1+, 2+, 3+. DC, viruria and viremia prevalence, sensitivity, specificity, and likelihood ratio (LR) were determined (Table 2x2). Diagnosis efficacy of DC and viruria were compared to viremia. RESULTS: DC prevalence was 25%, viruria 61.7%, and viremia 42.5%. Positive and negative patients in each test had similar clinical, immunosuppressive, and histopathological characteristics. There was no case of viremia with chronic allograft nephropathy and, under treatment with sirolimus, patients had a lower viruria prevalence (p = 0.043). Intense viruria was the single predictive test for active infection (3+; LR = 2.8).1,6-4,9 CONCLUSION: DC, BKV-viruria and -viremia are commun findings under late kidney graft dysfunction. Viremia could only be predicted by intense viruria. These results should be considered under the context of BKN confirmation.


Assuntos
Vírus BK/isolamento & purificação , Transplante de Rim/efeitos adversos , Infecções por Polyomavirus/diagnóstico , Disfunção Primária do Enxerto/virologia , Infecções Tumorais por Vírus/diagnóstico , Adulto , Vírus BK/genética , DNA Viral/sangue , DNA Viral/urina , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase , Prevalência , Disfunção Primária do Enxerto/diagnóstico , Sensibilidade e Especificidade
17.
Cancer Genet Cytogenet ; 196(2): 153-8, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20082851

RESUMO

We studied the possible association between Ala16Val manganese-dependent superoxide dismutase (MnSOD) gene genotypes and breast cancer lymph node status because previous investigations suggested an association between the AA genotype and breast cancer. We included 281 women (188 controls and 93 cases of invasive breast cancer with axillary lymph node metastasis (LN+) and without lymph node metastasis (LN-). DNA was extracted from paraffin-embedded tumor tissue or peripheral blood leukocytes, and MnSOD polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism techniques. In addition, the immunohistochemical profile (p53, Ki-67 and estrogen/progesterone receptors) was also compared between invasive breast cancer groups and different MnSOD genotypes. The frequency of the VV genotype was higher in the LN+ group than in the control and LN- groups (chi(2)=5.081, P=0.02). Subjects with LN+ breast cancer (LN+ group) showed a higher incidence of VV genotype carriers associated with positive Ki-67 marker. Subjects with LN+ breast cancer (LN+ group) showed a higher incidence of VV genotype carriers associated with negative p53 marker. Despite the fact that the AA genotype is well established as being associated with an increased risk of breast cancer, the VV genotype may be associated with a higher metastatic potential, suggesting that MnSOD imbalance is the condition associated with carcinogenesis.


Assuntos
Alanina/genética , Neoplasias da Mama/genética , Linfonodos/patologia , Polimorfismo Genético , Valina/genética , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Feminino , Frequência do Gene , Genótipo , Humanos , Linfonodos/enzimologia , Pessoa de Meia-Idade , Superóxido Dismutase/genética
18.
World J Gastroenterol ; 15(36): 4566-70, 2009 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-19777616

RESUMO

AIM: To investigate the potential role of p53 codon 72 polymorphism as a risk factor for development of anal cancer. METHODS: Thirty-two patients with invasive anal carcinoma and 103 healthy blood donors were included in the study. p53 codon 72 polymorphism was analyzed in blood samples through polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing. RESULTS: The relative frequency of each allele was 0.60 for Arg and 0.40 for Pro in patients with anal cancer, and 0.61 for Arg and 0.39 for Pro in normal controls. No significant differences in distribution of the codon 72 genotypes between patients and controls were found. CONCLUSION: These results do not support a role for the p53 codon 72 polymorphism in anal carcinogenesis.


Assuntos
Neoplasias do Ânus/genética , Genes p53 , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Ânus/epidemiologia , Códon , Feminino , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Genético , Fatores de Risco , Estatística como Assunto
19.
Cancer Detect Prev ; 30(6): 523-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17113725

RESUMO

BACKGROUND: A common Arg/Pro polymorphism at codon 72 of the TP53 gene has been investigated as a risk factor for cancer in different populations. So far, the results have been controversial. Our purpose was to investigate the association of this polymorphism with breast carcinoma in women from Southern Brazil, a high-risk area for breast cancer. METHODS: Blood samples collected from 118 women with primary breast carcinoma and from 202 female blood donors were analyzed through polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing. RESULTS: The relative frequency of each allele was 0.75 for Arg and 0.25 for Pro in patients with cancer, and 0.62 for Arg and 0.38 for Pro in normal controls (P < 0.001). The Arg/Arg genotype was significantly associated with an increased risk for breast cancer (OR 2.9; 95% CI 1.43-3.6; P < 0.002). No correlation between the genotype distribution and specific prognostic predictors for the disease outcome was observed. DISCUSSION: TP53 codon 72 polymorphism might be implicated in breast carcinogenesis, with the Arg/Arg genotype being associated with an increased susceptibility for this malignancy.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal/genética , Carcinoma Lobular/genética , Genes p53 , Predisposição Genética para Doença , Polimorfismo Genético , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Arginina/genética , Brasil/epidemiologia , Neoplasias da Mama/epidemiologia , Carcinoma Ductal/epidemiologia , Carcinoma Lobular/epidemiologia , Códon , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Prolina/genética , Fatores de Risco
20.
Rev. bras. colo-proctol ; 30(3): 281-288, jul.-set. 2010. ilus, tab
Artigo em Português | LILACS | ID: lil-565019

RESUMO

As variáveis clínico-patológicas são importantes fatores que possam estar associados à progressão da neoplasia e, consequentemente, ao prognóstico da doença. As glutationas S-Transferases GSTM1, GSTT1 e GSTP1 são enzimas da segunda fase de biotransformação que atuam na destoxificação de uma ampla variedade de agentes exógenos incluindo os carcinógenos. Os genes GSTM1, GSTT1 e GSTP1 são polimórficos em humanos e suas variantes têm sido associadas, em algumas populações, ao aumento dos riscos de neoplasia, entre elas o carcinoma colorretal. Neste estudo retrospectivo 50 biópsias de pacientes com carcinoma colorretal do Rio Grande do Sul foram analisadas os polimorfismos nos genes GSTM1, GSTT1 e GSTP1 por PCR multiplex e RFLP, quanto às variáveis clínico-patológicas: localização, estadiamento e diferenciação. Não foram encontrados valores p significativo nas variáveis: estadiamento (p=0,28, p=0,93 e p=0,67), diferenciação (p=0,70 e p=0,37) e localização (p= 0,23. p= 0,58 e p= 0,60 ) respectivamente e o presença do polimorfismos dos genes GSTM1, GSTT1 e GSTP1 nas variáveis estadiamento e localização. A única variável clínico-patológica que apresentou valor significativo na diferenciação do CCR foi o polimorfismo do gene GSTP1 Ile/val e val/val (p= 0,046) entretanto, mais pesquisas são necessárias para confirmar estes achados ,visto que, esses resultados podem ter sido influenciados pelo número reduzido de biópsias analisadas.


The clinical and pathological variables are important factors that may be associated with tumor progression and consequently, the prognoses of the disease. The glutathione S-Transferases GSTM1, GSTT1 and GSTP1 are enzymes from the second phase II of biotransformation that work in the detoxificatin pathways of a wide range of exogen agents including the carcinogens. The GSTM1, GSTT1 and GSTP1 genes are polymorphic in humans and their variants have been related in some populations an increased neoplasia risks, including colorectal cancer. In this retrospective study 50 biopsies of patients with colorectal carcinoma of South Brazilian were analyzed polymorphisms in the genes GSTM1, GSTT1 and GSTP1 by Multiplex PCR and RFLP for the clinical and pathological variables: location, stage and differentiation. There were no significant p values for the variables: stage (p=0,28, p=0,93 e p=0,67), differentiation (p=0,70 e p=0,37) and location (p= 0,23. p= 0,58 e p= 0,60 ) respectively and the presence of polymorphism of GSTM1, GSTT1 and GSTP1 in variables staging and location. The only clinicopathological variable that showed significant value in the differentiation of CCR was the polymorphism GSTP1 ile/val and val/val (p= 0,046), however, more research is needed to confirm these findings, since these results may have been influenced by the reduced number of biopsies analyzed.


Assuntos
Humanos , Neoplasias Colorretais , Glutationa , Estadiamento de Neoplasias , Polimorfismo Genético
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