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1.
Sci Rep ; 12(1): 3775, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260588

RESUMO

Loop-mediated isothermal amplification is known for its high sensitivity, specificity and tolerance to inhibiting-substances. In this work, we developed a device for performing real-time colorimetric LAMP combining the accuracy of lab-based quantitative analysis with the simplicity of point-of-care testing. The device innovation lies on the use of a plastic tube anchored vertically on a hot surface while the side walls are exposed to a mini camera able to take snapshots of the colour change in real time during LAMP amplification. Competitive features are the rapid analysis (< 30 min), quantification over 9 log-units, crude sample-compatibility (saliva, tissue, swabs), low detection limit (< 5 copies/reaction), smartphone-operation, fast prototyping (3D-printing) and ability to select the dye of interest (Phenol red, HNB). The device's clinical utility is demonstrated in cancer mutations-analysis during the detection of 0.01% of BRAF-V600E-to-wild-type molecules from tissue samples and COVID-19 testing with 97% (Ct < 36.8) and 98% (Ct < 30) sensitivity when using extracted RNA and nasopharyngeal-swabs, respectively. The device high technology-readiness-level makes it a suitable platform for performing any colorimetric LAMP assay; moreover, its simple and inexpensive fabrication holds promise for fast deployment and application in global diagnostics.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , COVID-19/virologia , Teste de Ácido Nucleico para COVID-19/instrumentação , Colorimetria , Humanos , Limite de Detecção , Técnicas de Diagnóstico Molecular , Nasofaringe/virologia , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/patologia , Técnicas de Amplificação de Ácido Nucleico , Testes Imediatos , Proteínas Proto-Oncogênicas B-raf/genética , RNA Viral/análise , RNA Viral/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade , Smartphone
2.
Infect Genet Evol ; 79: 104212, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32004758

RESUMO

BACKGROUND: A novel coronavirus (2019-nCoV) associated with human to human transmission and severe human infection has been recently reported from the city of Wuhan in China. Our objectives were to characterize the genetic relationships of the 2019-nCoV and to search for putative recombination within the subgenus of sarbecovirus. METHODS: Putative recombination was investigated by RDP4 and Simplot v3.5.1 and discordant phylogenetic clustering in individual genomic fragments was confirmed by phylogenetic analysis using maximum likelihood and Bayesian methods. RESULTS: Our analysis suggests that the 2019-nCoV although closely related to BatCoV RaTG13 sequence throughout the genome (sequence similarity 96.3%), shows discordant clustering with the Bat_SARS-like coronavirus sequences. Specifically, in the 5'-part spanning the first 11,498 nucleotides and the last 3'-part spanning 24,341-30,696 positions, 2019-nCoV and RaTG13 formed a single cluster with Bat_SARS-like coronavirus sequences, whereas in the middle region spanning the 3'-end of ORF1a, the ORF1b and almost half of the spike regions, 2019-nCoV and RaTG13 grouped in a separate distant lineage within the sarbecovirus branch. CONCLUSIONS: The levels of genetic similarity between the 2019-nCoV and RaTG13 suggest that the latter does not provide the exact variant that caused the outbreak in humans, but the hypothesis that 2019-nCoV has originated from bats is very likely. We show evidence that the novel coronavirus (2019-nCov) is not-mosaic consisting in almost half of its genome of a distinct lineage within the betacoronavirus. These genomic features and their potential association with virus characteristics and virulence in humans need further attention.


Assuntos
Betacoronavirus/genética , Genoma Viral , Filogenia , Recombinação Genética , COVID-19 , Infecções por Coronavirus/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Pandemias , Pneumonia Viral/virologia , SARS-CoV-2
3.
Front Pharmacol ; 11: 522213, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33390932

RESUMO

This review performs a comprehensive assessment of the therapeutic potential of three native herbs of Crete (Thymbra capitata (L.) Cav., Salvia fruticosa Mill. and Origanum dictamnus L.), their phytochemical constituents, health benefits and issues relevant to their safety, within a translational context. Issues discussed comprise: 1) Ethnopharmacological uses of the three herbs, reviewed through an extensive search of the literature; 2) Systematic analysis of the major phytochemical constituents of each plant, and their medicinal properties; 3) To what extent could the existing medicinal properties be combined and produce an additive or synergistic effect; 4) Possible safety issues. We conclude with a specific example of the use of a combination of the essential oils of these plants as an effective anti-viral product and the experience gained in a case of a plant-based pharmaceutical development, by presenting the major steps and the continuum of the translational chain.

4.
J Ethnopharmacol ; 163: 157-66, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25645191

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Observations from the island of Crete, Greece suggest that infusions of traditional Cretan aromatic plants, well known for their ethnopharmacological use in Eastern Mediterranean region and Near East, could be effective in the prevention and treatment of upper respiratory tract infections, including viral-induced infections. The aim of this study was to report the effectiveness of an essential-oil extract of three Cretan aromatic plants in the treatment of cases with an upper respiratory tract infection. MATERIALS AND METHODS: A double blind randomized controlled trial was implemented between October 2013 and February 2014. An essential-oil extract of Cretan aromatic plants in olive oil (total volume of 15ml of essential oil per litre of olive oil) was administered as 0.5ml soft gel capsules, twice a day, for 7 days. Placebo treatment was 0.5ml olive oil in soft gel capsules. Eligible patients were those presenting for clinical examination in the selected setting with signs and symptoms of upper respiratory tract infection that had begun within the previous 24 hours. Real-Time Polymerase Chain Reaction (PCR) was used for the detection of respiratory viruses. The primary outcome was the severity and duration of symptoms of upper respiratory tract infection, assessed using the Wisconsin Upper Respiratory System Survey (WURSS-21) questionnaire. A secondary outcome of interest was the change in C-reactive protein (CRP) status. RESULTS: One hundred and five patients completed the study: 51 in the placebo group, and 54 in the intervention (treated) group. Baseline characteristics were similar in the two groups. No statistically significant differences were found in symptom duration or severity between the two groups, although small and clinically favorable effects were observed. When the analysis was restricted to subjects with a laboratory-documented viral infection, the percentage of patients with cessation of symptoms after 6 days of treatment was 91% in the intervention group and 70% in the control group (p=0.089). At baseline, one third of the patients in each group had elevated CRP levels. At follow-up, the respective proportions were 0% in the intervention group and 15% in the placebo group (p=0.121). The data were also in a favorable direction when 50% and 80% symptom reduction points were considered for specific virus types. CONCLUSIONS: Compared with placebo the essential-oil extract of three Cretan aromatic plants provided no detectable statistically significant benefit or harm in the patients with upper respiratory illness, although descriptive differences were identified in favorable direction mainly in the virus-positive population.


Assuntos
Lamiaceae , Óleos Voláteis/uso terapêutico , Fitoterapia , Extratos Vegetais/uso terapêutico , Infecções Respiratórias/tratamento farmacológico , Viroses/tratamento farmacológico , Adulto , Proteína C-Reativa/análise , DNA Viral/análise , Método Duplo-Cego , Feminino , Grécia , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , Infecções Respiratórias/sangue , Infecções Respiratórias/virologia , Resultado do Tratamento , Viroses/sangue , Viroses/virologia
5.
Int J Cancer ; 133(3): 604-11, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23355004

RESUMO

Polyomaviruses such as BK virus (BKV), JC virus (JCV) and Merkel cell polyomavirus (MCPyV) are typically nononcogenic, although they have been detected in a variety of human neoplasms. The aim of our study was to determine the frequency of the most common polyomaviruses MCPyV, BKV and JCV as well as the gene expression profile of genes involved in oncogenesis including K-ras, BRAF, RKIP, Bax, Bcl-2, p53 and RB1 in a cohort of non-small cell lung cancer (NSCLC) patients. Real-time and nested polymerase chain reaction (PCR) were used to assess the presence of polyomaviruses DNA in tissue biopsies from 110 patients with primary NSCLC and 14 tissue specimens from macroscopically healthy sites of their lung. Real-time PCR was also used to determine the mRNA expression of K-ras, BRAF, RKIP, Bax, Bcl-2, p53 and RB1 in selected samples. Results showed that ten NSCLC specimens were positive for the presence of MCPyV DNA (10/110, 9.1%), whereas no control sample was tested positive for the virus. The MCPyV-positive samples were predominantly obtained from male smokers (9/10). BKV and JCV DNA were not detected either in lung tissues biopsies or the control specimens. Interestingly, gene expression analysis revealed increased mRNA and protein expression of BRAF gene in association with BRAF phosphorylation in the MCPyV-positive samples, whereas Bcl-2 gene expression was downregulated in the same type of samples. The detected MCPyV prevalence in NSCLC in combination with the deregulated expression of BRAF and Bcl-2 genes suggests that these events are likely to contribute to the pathogenesis of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Poliomavírus das Células de Merkel/imunologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Idoso , Carcinoma Pulmonar de Células não Pequenas/virologia , DNA Viral/genética , Feminino , Humanos , Neoplasias Pulmonares/virologia , Masculino , Poliomavírus das Células de Merkel/isolamento & purificação , Pessoa de Meia-Idade , Proteína de Ligação a Fosfatidiletanolamina/genética , Infecções por Polyomavirus/genética , Infecções por Polyomavirus/virologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fumar , Proteína Supressora de Tumor p53/genética , Infecções Tumorais por Vírus/genética , Proteínas ras/genética
6.
Int J STD AIDS ; 23(3): 185-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22581872

RESUMO

Our study aimed to examine the relationship between the presence of human papillomavirus (HPV) in the oral cavity of children and their mode of delivery. We investigated the presence of HPV infection in oral biopsies from 190 children (mean age: 7 years, range: 2-14 years) using the polymerase chain reaction (PCR) technique. Sixteen of 190 children (8.4%) were HPV-positive, with no significant difference between those delivered vaginally and by Caesarean section (C-section). The majority of the HPV-positive children were infected with type 16, whereas in the younger age group HPV type 11 was detected more frequently in children delivered by normal vaginal delivery (NVD) than by C-section. Our findings demonstrate the presence of HPV in the oral cavity of children delivered by both C-section as well as NVD. Further research on the possible modes of transmission of oral HPV infection will enable us to understand the natural history of HPV infection in childhood.


Assuntos
Boca/virologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Humanos , Masculino , Papillomaviridae/classificação , Papillomaviridae/genética , Infecções por Papillomavirus/transmissão , Reação em Cadeia da Polimerase , Prevalência , Estudos Retrospectivos , Estados Unidos
7.
J Bone Joint Surg Br ; 93(9): 1253-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21911538

RESUMO

It has been proposed that intervertebral disc degeneration might be caused by low-grade infection. The purpose of the present study was to assess the incidence of herpes viruses in intervertebral disc specimens from patients with lumbar disc herniation. A polymerase chain reaction based assay was applied to screen for the DNA of eight different herpes viruses in 16 patients and two controls. DNA of at least one herpes virus was detected in 13 specimens (81.25%). Herpes Simplex Virus type-1 (HSV-1) was the most frequently detected virus (56.25%), followed by Cytomegalovirus (CMV) (37.5%). In two patients, co-infection by both HSV-1 and CMV was detected. All samples, including the control specimens, were negative for Herpes Simplex Virus type-2, Varicella Zoster Virus, Epstein Barr Virus, Human Herpes Viruses 6, 7 and 8. The absence of an acute infection was confirmed both at the serological and mRNA level. To our knowledge this is the first unequivocal evidence of the presence of herpes virus DNA in intervertebral disc specimens of patients with lumbar disc herniation suggesting the potential role of herpes viruses as a contributing factor to the pathogenesis of degenerative disc disease.


Assuntos
Citomegalovirus/isolamento & purificação , DNA Viral/isolamento & purificação , Herpesvirus Humano 1/isolamento & purificação , Degeneração do Disco Intervertebral/virologia , Deslocamento do Disco Intervertebral/virologia , Vértebras Lombares/virologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Infecções por Citomegalovirus/complicações , Feminino , Herpes Simples/complicações , Humanos , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Fator de Necrose Tumoral alfa/sangue , Adulto Jovem
8.
J BUON ; 15(1): 174-81, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20414947

RESUMO

Retroviruses have been found in many bird and animal species where they often cause various types of cancer. Dr. Robert Gallo's contribution to the field of retrovirology and the link he established between RNA viruses and cancer has been significant. Historical aspects of his discoveries in the area of human retroviruses are presented and an attempt is made to focus attention on his outstanding role.


Assuntos
Neoplasias/história , Infecções por Retroviridae/história , Retroviridae , Infecções Tumorais por Vírus/história , Animais , Linhagem Celular Tumoral , HIV/isolamento & purificação , Infecções por HIV/história , História do Século XX , História do Século XXI , Humanos , Interleucina-2/história , Neoplasias/virologia , Retroviridae/isolamento & purificação , Infecções por Retroviridae/virologia , Infecções Tumorais por Vírus/virologia
10.
Acta Paediatr ; 97(12): 1669-71, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18754827

RESUMO

AIM: Human papilloma virus (HPV) can be transmitted via sexual as well as nonsexual routes. Recently, 'high-risk' HPVs were detected in the oral mucosa of children in whose cases there was no suspicion of sexual abuse. This implies that HPV 16 and 18 have additional nonsexual modes of transmission in childhood, such as vertical transmission and autoinoculation. METHODS: Using polymerase chain reaction (PCR) assays, we examined the skin tissues of 12 children with benign skin lesions, aged between 6 and 13 years, for the presence of HPV. RESULTS: Among 12 biopsy skin specimens, no 'high-risk' HPV DNA was detected. Specific PCRs for HPV DNA 16 and 18 were also negative. CONCLUSION: This preliminary case-control study indicates the absence of mucosal 'high-risk' HPV types in the benign skin lesions of children.


Assuntos
Papillomavirus Humano 11/isolamento & purificação , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Neoplasias Cutâneas/virologia , Verrugas/virologia , Adolescente , Estudos de Casos e Controles , Criança , DNA Viral/isolamento & purificação , Feminino , Papillomavirus Humano 11/genética , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Masculino , Projetos Piloto , Reação em Cadeia da Polimerase , Neoplasias Cutâneas/patologia
11.
Int J Biol Markers ; 22(4): 245-51, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18161654

RESUMO

Polyomaviruses such as the BK virus (BKV), JC virus (JCV) and SV40, as well as the human papillomaviruses (HPV) are frequently detected throughout human populations, causing subclinical persistent infections and inducing oncogenesis in human and other cell lines. To test the involvement of these viruses in prostate tumorigenesis, we investigated the prevalence of BKV, JCV and HPV in a series of human prostatic malignancies. Forty-two samples of diagnosed prostatic malignancies were tested using standard polymerase chain reaction (PCR) protocols. Differentiation between BKV and JCV among the polyomavirus-positive samples was achieved after sequencing analysis of the PCR products. Reconstitution of BKV in vitro was performed and indirect immunofluorescence for the large T-antigen of the virus was applied to confirm the production of progeny virus. Detection and typing of HPV was carried out by PCR. The overall prevalence of polyomaviruses was 19% in the prostate cancer cases. Sequencing analysis of the polyomavirus-positive specimens revealed the presence of BKV in all samples. Reconstitution of the BKV from the BKV-positive prostate samples was successfully achieved in cell culture and progeny viral particles were obtained, confirming the presence of the virus in the human biopsies. HPV was detected in 4.8% of the samples, however, no HPV-11, HPV-16, HPV-18 or HPV-33 types were identified. BKV was frequently detected and could play a relevant role in the development and progression of human prostate cancer, whereas HPV does not seem to be implicated in this type of human neoplasia.


Assuntos
Vírus BK/metabolismo , Papillomaviridae/metabolismo , Infecções por Polyomavirus/virologia , Neoplasias da Próstata/virologia , Idoso , Animais , Antígenos Virais de Tumores/metabolismo , Chlorocebus aethiops , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Polyomavirus/complicações , Prevalência , Neoplasias da Próstata/complicações , Análise de Sequência de DNA , Células Vero
12.
Int J Biol Markers ; 22(4): 239-44, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18161653

RESUMO

Although several studies have reported that oropharyngeal infection with HPV may predispose to tumorigenesis, little is known about the etiological factors of salivary gland tumors and the presence of HPV. We studied 9 parotid lesions for HPV infection including an oncocytoma, an acinic cell carcinoma, a high-grade adenocarcinoma, a low-grade polymorphous adenocarcinoma, a Warthin's tumor and 2 pleomorphic adenomas, a lymphoepithelial cyst and a lipoma of the parotid gland. DNA was extracted from formalin-fixed and paraffin-embedded tissue sections. Solution PCR for HPV detection was performed using the GP5+/GP6+ primers, while HPV typing was carried out by multiplex PCR for HPV6, 11, 16, 18, and 33; positive samples were recorfirmed by PCR with specific primers for each type. Quantitative real-time PCR for the high-risk HPV genotypes 16, 18, 31, 33, 35, 52, 58 and 67 was also performed to quantitate the viral load. Finally, in situ PCR was employed with HPV16-specific primers by direct-detection method. Seven of the 9 parotid lesions were HPV positive while 6 of these 7 had been infected by HPV16 and/or HPV18 oncogenic types. High viral load of highrisk genotypes of HPV was found in the oncocytoma, in one of the pleomorphic adenomas, and in the Warthin's tumor. Finally, in situ PCR indicated that HPV16 amplification occurred in the salivary gland tumors. This is the first time that highrisk HPV genotypes are detected in these histological types of parotid lesions, suggesting the possible involvement of the virus in the disease.


Assuntos
Papillomaviridae/metabolismo , Infecções por Papillomavirus/virologia , Glândula Parótida/patologia , Neoplasias Parotídeas/virologia , Neoplasias das Glândulas Salivares/virologia , Adolescente , Adulto , Criança , Sondas de DNA de HPV/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Risco , Neoplasias das Glândulas Salivares/complicações , Carga Viral
13.
AIDS Res Hum Retroviruses ; 23(8): 1026-32, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17725420

RESUMO

The chemokine polymorphisms CXCR6-3E/K, In1.1T/C, H7 haplotype, CX(3)CR1-V249I, and CX(3)CR1-T280M have been shown to affect the course of HIV infection. We studied their influence on immunologic and virologic response to HAART in a group of 143 HIV-1 patients. We performed Kaplan-Meier analysis using the following end-point criteria: (1) time from HAART initiation to undetectable viral load (VL < 50 copies/ml), (2) maximum duration of viral suppression, (3) time from HAART administration until CD4 elevation above 200 cells/microl for patients with baseline CD4 below 200 cells/microl and above 500 cells/microl for patients with baseline CD4 between 200 and 500 cells/microl, respectively, and (4) time from HAART initiation until CD4 reduction below baseline values. Our results revealed an improved immunologic response to HAART in patients with the CX(3)CR1-249I or CX(3)CR1-280M allele. On the contrary, patients with initial VL suppression due to HAART showed a faster virologic failure in the presence of the CXCR6-3K allele. The In1.1T/C polymorphism and H7 haplotype did not reveal any specific effect on HAART response.


Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , HIV-1 , Polimorfismo Genético , Receptores de Quimiocinas/genética , Receptores Virais/genética , Adulto , Idoso , Alelos , Contagem de Linfócito CD4 , Receptor 1 de Quimiocina CX3C , Feminino , Infecções por HIV/virologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Receptores CXCR6 , Carga Viral
14.
Aliment Pharmacol Ther ; 23(6): 787-95, 2006 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16556181

RESUMO

BACKGROUND: Factors that predict response and breakthrough phenomenon to lamivudine monotherapy in patients with HBeAg-negative chronic hepatitis B have not been well defined. AIM: To determine pre-treatment and on treatment variables that predict initial response and breakthrough in patients with HBeAg-negative chronic hepatitis B receiving long-term lamivudine. METHODS: Seventy-nine patients, with chronic HBeAg-negative hepatitis B, who received lamivudine for a median of 31 months were included in the study. RESULTS: Initial virologic and biochemical response was observed in 73 (92%) and 70 (89%) patients, respectively, while 34 (47%) and 15 (21%) patients developed virological and biochemical breakthrough, respectively. High levels of necroinflammation in liver biopsy were associated with a higher probability of initial virological and biochemical response. Patients with pre-treatment serum hepatitis B virus DNA concentrations of more than 10(6) copies/mL were three times more likely to develop virologic breakthrough. Two patients died, one with baseline cirrhosis because of liver failure during biochemical breakthrough while the second death was liver and treatment unrelated. CONCLUSIONS: In HBeAg-negative chronic hepatitis B, initial response to lamivudine therapy is associated with necroinflammation, while baseline serum hepatitis B virus DNA exceeding 10(6) copies/mL is a strong predictor for breakthrough because of drug-resistant mutations. Severe complications are uncommon and are associated with biochemical breakthrough and pre-existing cirrhosis.


Assuntos
Antivirais/uso terapêutico , Antígenos E da Hepatite B/imunologia , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Adolescente , Adulto , Idoso , DNA Viral/análise , Farmacorresistência Viral , Feminino , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Humanos , Fígado/imunologia , Fígado/patologia , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Mutação , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Resultado do Tratamento
15.
Int J Biol Markers ; 20(4): 257-63, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16398408

RESUMO

OBJECTIVE: Human papillomavirus (HPV) has been identified as the principal etiologic agent for cervical cancer and its precursors. Different HPV types have been associated with different oncogenic potential. The purpose of this study was to evaluate the relationship between specific HPV type infection and expression pattern of the ras family oncogenes in different grades of HPV-associated human cervical neoplasia. METHODS: HPV typing was performed using polymerase chain reaction (PCR) in 31 HPV-positive human cervical specimens from patients with squamous intraepithelial lesions (SIL) or squamous cervical carcinoma (SCC). The mRNA expression levels of H-, K- and N-ras oncogenes were examined using the reverse transcriptase polymerase chain reaction (RT-PCR) technique. Statistical analyses were performed using SPSS software. RESULTS: Among patients with SCC, H-, K- and N-ras expression levels were higher in HPV 16/18-associated cases compared to HPV 16/18-unassociated samples (p=0.003, p=0.004 and p=0.0001, respectively). The expression levels for H-, K- and N-ras were significantly higher in SCC patients with multiple HPV infection compared with SCC patients with single HPV infection (p=0.009, p=0.01 and p=0.021, respectively). Among patients with SIL, no statistically significant relationship was found between ras expression and HPV status. CONCLUSION: Our findings indicate the possible role of ras signaling interaction with "high-risk" HPV 16/18 and multiple HPV infection in cervical cancer development.


Assuntos
Carcinoma de Células Escamosas/genética , Regulação Neoplásica da Expressão Gênica/genética , Genes ras/genética , Papillomaviridae/classificação , Infecções por Papillomavirus/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , Carcinoma de Células Escamosas/virologia , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
16.
Eur Respir J ; 22(6): 951-5, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14680084

RESUMO

Genetic alterations, such as loss of heterozygosity (LOH) or microsatellite instability (MI), have been reported in both malignant and benign disorders. In order to identify loci of deoxyribonucleic acid (DNA) mutation in asthma, MI and LOH were studied in sputum cells. DNA was extracted from cells in the sputum and blood cells of 22 patients with moderate asthma. Cells were analysed for MI and LOH using 18 polymorphic markers on chromosome 5q, 6p, 11q, 14q. Microsatellite analysis was also performed in six healthy subjects. None of the healthy individuals exhibited any genetic alteration. Genetic alterations were found in 16 of 22 asthmatic patients (73%). In total, 12 (54.5%) patients exhibited LOH only, one (4.5%) MI only, while three showed both MI and LOH. The highest incidence of LOH and MI was found on chromosome 14q. Mean immunoglobulin E and blood eosinophil levels were significantly higher in asthmatics with three or more genetic alterations. A high incidence of genetic alterations in the deoxyribonucleic acid of the sputum cells was found in asthmatic patients. Further studies are needed to identify the role of loss of heterozygosity and microsatellite instability in the investigation of genetic susceptibility of asthma and thus, in its pathogenesis.


Assuntos
Asma/genética , Instabilidade Cromossômica/genética , Perda de Heterozigosidade/genética , Repetições de Microssatélites/genética , Adulto , Células Sanguíneas/química , Feminino , Predisposição Genética para Doença , Testes Genéticos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Escarro/química , Escarro/citologia
17.
Int J Oncol ; 21(2): 237-41, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12118316

RESUMO

The ras family of oncogenes has been extensively studied for its implication in several types of human malignancies. Activation of ras genes involves mutations that alter the catalytic activity of the protein enhancing the downstream signals mostly towards cell proliferation and malignant transformation. Ras genes are also involved in induction of senescence or apoptosis, suggesting activation of alternative pathways that may be anti-oncogenic. Early experiments showed that transfection of wild-type ras in transformed cells reversed the oncogenic phenotype suggesting that wild-type ras has onco-suppressive properties. Indeed, expression of wild-type ras genes in several human malignancies is associated with good prognosis. In tumors carrying mutant ras genes the levels of expression of the wild-type allele never exceeded the mutant counterpart, indicating that the wild-type protein suppresses the effect of the mutant one. Recent development of the Kras2 deficient mice provided the tool to study the role of wild-type ras genes in tumorigenesis.


Assuntos
Apoptose , Genes ras/fisiologia , Animais , Humanos , Neoplasias/genética
18.
Int J Biol Markers ; 16(3): 167-71, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11605728

RESUMO

OBJECTIVE: Atherosclerosis is a fibroproliferative disease which has been attributed to several factors including genetic and molecular alterations. Initial studies have shown genetic alterations at the microsatellite level in the DNA of atherosclerotic plaques. Extending our initial findings, we performed a microsatellite analysis on cerebral atherosclerotic plaques. METHODS: Twenty-seven cerebral atherosclerotic plaques were assessed for loss of heterozygosity (LOH) and microsatellite instability (MI) using 25 microsatellite markers located on chromosomes 2, 8, 9 and 17. DNA was extracted from the vessels as well as the respective blood from each patient and subjected to polymerase chain reaction. RESULTS: Our analyses revealed that specific loci on chromosomes 2, 8, 9 and 17 exhibited a significant incidence of LOH. Forty-six percent of the specimens showed loss of heterozygosity at 2p13-p21, 48% exhibited LOH at 8p12-q11.2, while allelic imbalance was detected in 47% of the cases. The LOH incidence was 39%, 31% and 27% at 17q21, 9q31-34 and 17p13, respectively. Genetic alterations were detected at a higher rate as compared to the corresponding alterations observed in plaques from other vessels. DISCUSSION: This is the first microsatellite analysis using atherosclerotic plaques obtained from cerebral vessels. Our results indicate an elevated mutational rate on specific chromosomal loci, suggesting a potential implication of these regions in atherogenesis.


Assuntos
Cromossomos Humanos Par 17 , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 2 , Cromossomos Humanos Par 8 , Cromossomos Humanos Par 9 , Arteriosclerose Intracraniana/genética , Perda de Heterozigosidade , Marcadores Genéticos , Humanos , Repetições de Microssatélites
19.
Sarcoidosis Vasc Diffuse Lung Dis ; 18(3): 307-10, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11587105

RESUMO

BACKGROUND: Genetic alterations at the microsatellite level have been detected in various human malignant tissues, but have also been found in chronically inflamed tissues. Sarcoidosis is a benign disease of unknown etiology characterized by chronic inflammation, which may be associated with an increased incidence of developing malignancy. METHODS: We examined the microsatellite alterations in a sputum cytological specimen of a patient with sarcoidosis. The DNA electrophoretic pattern of sputum was compared with that of the peripheral blood. Thirty-two microsatellite markers located at chromosomes 2p, 3p, 8p, 9p, 9q, 17p, 17q were used to reveal genetic alterations. RESULTS: Loss of heterozygosity (LOH) was detected in eleven markers in loci 2p, 9p, 9q and 17q. LOH was observed in all four markers spanning the chromosomal arm 17q11.2-q21, suggesting a potential chromosomal deletion. CONCLUSION: The observation of LOH in all four markers spanning the chromosomal arm 17q11.2-q21 may suggest a potential for malignancy development in this patient, or may be linked to the aetiopathogenesis of sarcoidosis. Further microsatellite fine mapping and clinical follow up of this patient are needed to clarify this.


Assuntos
Cromossomos Humanos Par 17/genética , Repetições de Microssatélites/genética , Sarcoidose Pulmonar/genética , Adulto , Deleção Cromossômica , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Perda de Heterozigosidade , Masculino
20.
Oral Oncol ; 37(7): 572-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11564578

RESUMO

The p53 codon 72 polymorphism, resulting in either an arginine or a proline residue has been proposed to affect the susceptibility of p53 protein to human papilloma virus (HPV) E6-mediated degradation in vitro. However, there are controversial results from several clinical studies in various human tumours. The purpose of our study was to investigate the significance of this p53 genotype with respect to the risk of neoplasia development in Greek patients with benign and malignant laryngeal tumours. Furthermore, we searched for an association between p53 alleles and the presence of HPV in the same series of samples. We found a significant statistical association in the distribution of p53 genotypes between laryngeal lesions and normal samples (P<0.001). Allelic analysis of the patients with both benign and malignant tumours revealed a striking over-representation of the homozygous p53Arg allele compared to normal population (P<0.0003). HPV was detected in only 3 laryngeal samples (1 benign and 2 malignant tumours). This is the first study correlating the p53 codon 72 polymorphism in laryngeal tumours. Our results provide evidence that this p53 polymorphism may be implicated at the early stages of the disease and concerns predisposition to premalignant laryngeal lesions rather than to progression from benign tumour toward malignancy. Moreover, we demonstrate that the p53Arg homozygous genotype affects the predisposition for laryngeal tumours while the heterozygous status does not. The low incidence of HPV infection suggests that it is not a major oncogenic factor in the development of laryngeal tumours but may have synergistic action with specific genotypes of p53 gene.


Assuntos
Carcinoma de Células Escamosas/genética , Genes p53/genética , Neoplasias Laríngeas/genética , Papillomaviridae/isolamento & purificação , Polimorfismo Genético , Carcinoma de Células Escamosas/virologia , Transformação Celular Neoplásica/genética , Códon , Progressão da Doença , Predisposição Genética para Doença , Humanos , Neoplasias Laríngeas/virologia , Papillomaviridae/classificação , Reação em Cadeia da Polimerase/métodos
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