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2.
Int J Oral Maxillofac Surg ; 51(4): 473-480, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34503889

RESUMO

There is a lack of effective clinical management of oral epithelial dysplasias to reduce their risk of malignant transformation and considerable gaps in knowledge regarding the most effective means of treating such lesions. A retrospective cohort of biopsy-confirmed oral epithelial dysplasias consecutively diagnosed in the period 1995-2014 and followed-up until 2017 was identified from pathology department files. Demographic, clinical and follow-up information was collected. Multivariate Cox proportional-hazards models were performed to evaluate sociodemographic, clinical and pathological factors associated with progression to oral squamous cell carcinoma. The study included 144 oral epithelial dysplasias, of which 42% progressed to oral cancer at the end of follow-up (21 years). Clinical aspect of the lesion was described for 77 (53.5%) of the patients. Treatment, age, grade of the lesion and diagnostic period were independent prognostic factors for progression. When considering only patients with described clinical aspect, only treatment and grade of the lesion were independently associated with cancer. The results from this non-selected retrospective cohort of oral epithelial dysplasias underscore the existing limitations of the current standard-of-care of the patients and provide novel insights on the management of these lesions with and without described clinical aspect. Well-designed, robust prospective studies, a homogenized staging system and multidisciplinary treatment guidelines are warranted.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Lesões Pré-Cancerosas , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Transformação Celular Neoplásica/patologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Leucoplasia Oral , Mucosa Bucal/patologia , Neoplasias Bucais/patologia , Neoplasias Bucais/terapia , Lesões Pré-Cancerosas/patologia , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco
3.
Rev Esp Quimioter ; 34(6): 525-555, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34348449

RESUMO

The role of certain viruses in the etiology of some tumors is today indisputable, but there is a lack, however, of annoverview of the relationship between viruses and cancer with amultidisciplinary approach. For this reason, the Health Sciences Foundation has convened a group of professionals from different areas of knowledge to discuss the relationship between viruses and cancer, and the present document is the result of these deliberations. Although viruses cause only 10-15% of cancers, advances in oncology research are largely due to the work done during the last century on tumor viruses. The clearest cancer-inducing viruses are: HPV, HBV, HCV, EBV and, depending on the geographical area, HHV-8, HTLV-1 and HIV. HPVs, for example, are considered to be the causative agents of cervical carcinomas and, more recently, of a proportion of other cancers. Among the Herpes viruses, the association with the development of neoplasms is well established for EBV and HHV-8. Viruses can also be therapeutic agents in certain neoplasms and, thus, some oncolytic viruses with selective tropism for tumor cells have been approved for clinical use in humans. It is estimated that the prophylaxis or treatment of viral infections could prevent at least 1.5 million cancer deaths per year.


Assuntos
Neoplasias , Viroses , Humanos , Vírus Oncogênicos , Papillomaviridae , Viroses/epidemiologia
4.
Sci Rep ; 10(1): 13219, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32764593

RESUMO

The incidence of human papillomavirus (HPV)-related oropharyngeal cancer is increasing in some regions. Nevertheless, the epidemiology of this disease has not been extensively investigated in southern Europe. We conducted a retrospective cohort study of patients diagnosed with primary oropharyngeal cancer from 1991 to 2016. Cancer tissues underwent histopathological evaluation, DNA quality control, HPV-DNA detection and p16INK4a immunohistochemistry. Data were collected from medical records. Factors associated with HPV positivity and time trends were evaluated with multivariable Bayesian models. The adjusted prevalence of HPV-related cases in 864 patients with a valid HPV-DNA result was 9.7%, with HPV-DNA/p16INK4a double positivity being considered. HPV-related oropharyngeal cancer was likely to occur in non-smokers and non-drinkers, to be located in the tonsil or diagnosed at advanced stages. Time-trend analysis showed an increasing risk of HPV-related oropharyngeal cancer in the most recent periods (5-year period increase of 30%). This increase was highest and with a clear increasing trend only in the most recent years (2012-2016). The prevalence of HPV-related oropharyngeal cancer started to sharply increase in the most recent years in our setting, as occurred two decades ago in areas where most oropharyngeal cancer cases are currently HPV-related. Our results provide a comprehensive assessment of the epidemiological landscape of HPV-related oropharyngeal cancer in a region of southern Europe.


Assuntos
Alphapapillomavirus , Neoplasias Orofaríngeas/epidemiologia , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Prevalência , Estudos Retrospectivos
5.
Head Neck Pathol ; 14(3): 768-770, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32040821

RESUMO

The original version of this article unfortunately contained a mistake. Three values in Table 1 were incorrect. In "months of recurrence", range row, the intervals should be in numbers. They should read as 3-83 instead of Mar-83, 9-83 instead of Sep-83 and 3-36 instead of Mar-36. The corrected Table 1 is given below. The original article has been corrected.

6.
Head Neck Pathol ; 14(3): 758-767, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31916205

RESUMO

Sinonasal inverted papilloma (SNIP) is a benign but locally aggressive tumor that has a tendency for recurrence and malignant transformation. The role of human papillomavirus (HPV) in SNIP is controversial. To determine the HPV-DNA prevalence and type distribution in SNIP in two different geographic areas and assess the association between SNIP recurrence and HPV infection, as well as additional potential etiologic factors. Two retrospective cohorts of SNIP patients from Poland and Spain were evaluated. Demographic, tobacco/alcohol use, clinical, and follow-up data were collected. All samples were subject to histopathologic evaluation, DNA quality control, and HPV-DNA detection by PCR. HPV-DNA positive samples and a random sample of HPV-DNA negative cases were further subject to p16INK4a analysis. Proportional-hazards models were used to evaluate the risk of recurrence by selected variables. Seventy-nine SNIP patients (46 from Spain diagnosed between 1995 and 2014, and 33 from Poland diagnosed between 2012 and 2017) were included in the study. HPV-DNA was detected in four patients (5.1%), two from each region, and all four were positive for the HPV11 subtype. Seventeen patients (21.5%) experienced recurrence, with a median time to recurrence of 14 months. No association was identified between lesional HPV-DNA positivity, toxic habits, Krouse stage, or malignant transformation and a higher risk of recurrence. The low prevalence of HPV-DNA in SNIPs suggests that HPV is not a main etiology for development of these lesions. With a lack of association between the evaluated factors and recurrence, further research with larger number of patients and additional biomarkers is warranted to further understand predisposing risk factors.


Assuntos
Recidiva Local de Neoplasia/virologia , Papiloma Invertido/patologia , Papiloma Invertido/virologia , Infecções por Papillomavirus/complicações , Neoplasias dos Seios Paranasais/patologia , Neoplasias dos Seios Paranasais/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasais/patologia , Neoplasias Nasais/virologia , Papillomaviridae , Infecções por Papillomavirus/epidemiologia , Polônia/epidemiologia , Prevalência , Estudos Retrospectivos , Espanha/epidemiologia , Adulto Jovem
7.
Ann Oncol ; 30(1): 57-67, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30462163

RESUMO

Anti-programmed cell death protein 1 (PD-1) agents have become the standard of care for platinum-refractory recurrent/metastatic head and neck squamous cell carcinoma (HNSCC) and are currently being evaluated in various disease settings. However, despite the gain in overall survival seen in some of the clinical trials, the majority of patients display primary resistance and do not benefit from these agents. Taking into consideration the potentially severe immune-related toxicities and their high cost, the search for predictive biomarkers of response is crucial. Besides Programmed death ligand-1 (PD-L1) expression, other biomarkers such as immune infiltration, tumor mutational burden or immune-gene expression profiling have been explored, but none of them has been validated in this disease. Among these, the microbiota has recently garnered tremendous interest since it has proven to influence the efficacy of PD-1 blockade in some tumor types. With the accumulating evidence on the effect of the microbiota in HNSCC tumorigenesis and progression, the study of its potential role as a predictive immune biomarker is warranted. This review examines the available evidence on emerging immune predictive biomarkers of response to anti-PD-1/PD-L1 therapy in HNSCC, introducing the microbiota and its potential use as a predictive immune biomarker in this disease.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Biomarcadores Tumorais/antagonistas & inibidores , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Antígeno B7-H1/imunologia , Biomarcadores Tumorais/imunologia , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
8.
Oral Oncol ; 81: 89-94, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29884419

RESUMO

OBJECTIVES: HPV16-positive oropharyngeal cancer (OPC) patients experience better outcomes compared to HPV16-negative patients. Currently, strategies for treatment de-escalation are based on HPV status, smoking history and disease stage. However, the appropriate cut-point for smoking and the role of other non-clinical factors in OPC survival remains uncertain. MATERIALS AND METHODS: We examined factors associated with OPC outcome in 321 patients recruited in a large European multi-center study. Seropositivity for HPV16 E6 was used as a marker of HPV16 positive cancer. Hazard ratios (HR) and confidence intervals (CI) were estimated using Cox proportional models adjusted for potential confounders. RESULTS: Overall 5-year survival following OPC diagnosis was 50%. HPV16-positive OPC cases were at significantly lower risk of death (aHR = 0.51, 95% CI: 0.32-0.80). A significant effect on OPC survival was apparent for female sex (aHR 0.50: 95% CI: 0.29-0.85) and being underweight at diagnosis (aHR: 2.41, 95% CI: 1.38-4.21). A 10 pack year smoking history was not associated with overall survival. Higher stage at diagnosis appeared as the only factor significantly associated with OPC recurrence (aHR: 4.88, 95% CI: 2.12-11.21). CONCLUSION: This study confirms that HPV16 status is an independent prognostic factor for OPC survival while female sex lowers risk of death and being underweight at diagnosis increases the risk of death. Smoking was not an independent predictor of OPC survival.


Assuntos
Neoplasias Orofaríngeas/patologia , Análise de Sobrevida , Alphapapillomavirus/isolamento & purificação , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasias Orofaríngeas/virologia , Estudos Retrospectivos , Fatores de Risco , Fumar , Infecções Tumorais por Vírus/patologia , Infecções Tumorais por Vírus/virologia
9.
Ann Oncol ; 28(10): 2386-2398, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28633362

RESUMO

High-risk human papillomavirus (HPV) is now recognised as the principal cause of the increasing incidence rates of oropharyngeal squamous cell carcinoma (OPSCC) in some parts of the world. The primary risk factor for developing HPV-related OPSCC is oral HPV-infection and the majority of oral HPV-infections are acquired by oral sex. Progression into an OPSCC includes persistent infection with evasion of immune response in the microenvironment, the activation of viral early genes (E6, E7) in basal epithelial cells, the deregulation of cell cycle and the accumulation of chromosomal instability. Patients affected by HPV-related OPSCC tend to be younger and have better outcomes. This observation has lead current research to evaluate treatment de-escalation options to reduce long-term associated morbidity. Moreover, a different molecular profile for HPV-related OPSCC has been described, opening new options for targeted therapy and immunotherapy approaches. This paper comprehensively reviews our accumulated knowledge regarding the role of HPV in OPSCC spanning from infection to cancer development, including its clinical diagnosis, management and preventive strategies.


Assuntos
Carcinoma de Células Escamosas/virologia , Neoplasias de Cabeça e Pescoço/virologia , Neoplasias Orofaríngeas/virologia , Papillomaviridae/fisiologia , Infecções por Papillomavirus/complicações , Humanos , Papillomaviridae/genética , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/virologia , Carcinoma de Células Escamosas de Cabeça e Pescoço
10.
Int J Cancer ; 140(9): 2092-2100, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28187495

RESUMO

Human Papillomavirus 16 (HPV16) causes 70% of invasive cervical cancers (ICC) worldwide. Interaction between HPV16 genetic diversity, host genetics and target tissue largely determine the chances to trigger carcinogenesis. We have analyzed the differential prevalence of viral variants in 233 HPV16-monoinfected squamous (SCC), glandular (ADC) and mixed (ADSC) ICCs from four continents, assessing the contribution of geographical origin and cancer histology. We have further quantified the contribution of viral variants and cancer histology to differences in age at tumor diagnosis. The model fitted to the data explained 97% of the total variance: the largest explanatory factors were differential abundance among HPV16 variants (78%) and their interaction with cancer histology (9.2%) and geography (10.1%). HPV16_A1-3 variants were more prevalent in SCC while HPV16_D variants were increased in glandular ICCs. We confirm further a non-random geographical structure of the viral variants distribution. ADCs were diagnosed at younger ages than SCCs, independently of the viral variant triggering carcinogenesis. HPV16 variants are differentially associated with histological ICCs types, and ADCs are systematically diagnosed in younger women. Our results have implications for the implementation of cervical cancer screening algorithms, to ensure proper early detection of elusive ADCs.


Assuntos
Adenocarcinoma/virologia , Carcinoma Adenoescamoso/virologia , Carcinoma de Células Escamosas/virologia , Neoplasias do Colo do Útero/virologia , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Adulto , Idoso , Carcinoma Adenoescamoso/epidemiologia , Carcinoma Adenoescamoso/patologia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Feminino , Genótipo , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 16/patogenicidade , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Filogenia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/patologia , Proteínas Virais/genética
12.
Clin Microbiol Infect ; 21(6): 605.e11-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25700891

RESUMO

Anal condylomata are common in HIV-positive individuals and among men who have sex with men (MSM). Generally attributable to infection by low-risk human papillomaviruses (HPVs), condylomata are considered benign low-grade squamous intraepithelial lesions (SILs). However, anal condylomata have occasionally been linked to high-grade SIL and to oncogenic, high-risk HPVs. Here we describe the range of intraepithelial lesions and of the associated HPVs in heterosexual men and women and MSM. Perianal and anal condylomata were collected from 243 patients (56 heterosexual women, 61 heterosexual men and 126 MSM, including 41 HIV-positive MSM). We assessed lesion histology and HPV genotype. Prevalence estimates and Poisson models were used. Irrespective of HIV infection status, MSM showed a higher proportion of condylomata as high-grade SILs compared to heterosexual men/women. High-grade SILs were also more prevalent in anal than in perianal lesions in all patient groups. HIV-positive MSM exhibited increased prevalence ratio (4.6; 95% confidence interval 2.1-10.0) of perianal low-grade SILs containing only high-risk HPVs compared to HIV-negative MSM. In addition, more than 64% of anal SILs with a high-grade component, regardless of HIV infection, were exclusively associated with low-risk HPVs. In anal condylomata, both high-grade and low-grade SILs can be associated with high-risk and/or low-risk HPVs. Particularly, low-grade perianal SILs associated with high-risk HPVs were common in HIV-positive MSM, while presence of only low-risk HPVs in high-grade SILs were common in both MSM groups. Our findings sound a note of caution for the common clinical practice for the treatment of anal condylomata as benign lesions in MSM and HIV-positive patients.


Assuntos
Neoplasias do Ânus/epidemiologia , Neoplasias do Ânus/patologia , Carcinoma in Situ/epidemiologia , Carcinoma in Situ/patologia , Infecções por HIV/complicações , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Adolescente , Adulto , Idoso , Neoplasias do Ânus/virologia , Carcinoma in Situ/virologia , Estudos Transversais , Feminino , Genótipo , Histocitoquímica , Homossexualidade Masculina , Humanos , Masculino , Pessoa de Meia-Idade , Papillomaviridae/classificação , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Prevalência , Medição de Risco , Adulto Jovem
13.
Eur J Cancer ; 50(16): 2846-54, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25155250

RESUMO

AIM: This work describes the human papillomavirus (HPV) prevalence and the HPV type distribution in a large series of vaginal intraepithelial neoplasia (VAIN) grades 2/3 and vaginal cancer worldwide. METHODS: We analysed 189 VAIN 2/3 and 408 invasive vaginal cancer cases collected from 31 countries from 1986 to 2011. After histopathological evaluation of sectioned formalin-fixed paraffin-embedded samples, HPV DNA detection and typing was performed using the SPF-10/DNA enzyme immunoassay (DEIA)/LiPA25 system (version 1). A subset of 146 vaginal cancers was tested for p16(INK4a) expression, a cellular surrogate marker for HPV transformation. Prevalence ratios were estimated using multivariate Poisson regression with robust variance. RESULTS: HPV DNA was detected in 74% (95% confidence interval (CI): 70-78%) of invasive cancers and in 96% (95% CI: 92-98%) of VAIN 2/3. Among cancers, the highest detection rates were observed in warty-basaloid subtype of squamous cell carcinomas, and in younger ages. Concerning the type-specific distribution, HPV16 was the most frequently type detected in both precancerous and cancerous lesions (59%). p16(INK4a) overexpression was found in 87% of HPV DNA positive vaginal cancer cases. CONCLUSIONS: HPV was identified in a large proportion of invasive vaginal cancers and in almost all VAIN 2/3. HPV16 was the most common type detected. A large impact in the reduction of the burden of vaginal neoplastic lesions is expected among vaccinated cohorts.


Assuntos
Carcinoma de Células Escamosas/virologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , Neoplasias Vaginais/virologia , Idoso , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/epidemiologia , Estudos Transversais , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , DNA Viral/análise , Feminino , Papillomavirus Humano 16/isolamento & purificação , Humanos , Técnicas Imunoenzimáticas , Cooperação Internacional , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Distribuição de Poisson , Lesões Pré-Cancerosas/epidemiologia , Lesões Pré-Cancerosas/virologia , Prevalência , Análise de Regressão , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias Vaginais/complicações , Neoplasias Vaginais/epidemiologia
14.
Food Chem Toxicol ; 69: 140-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24747512

RESUMO

High dietary intakes of cholesterol together with sedentary habits have been identified as major contributors to atherosclerosis. The latter has long been considered a cholesterol storage disease; however, today atherosclerosis is considered a more complex disease in which both innate and adaptive immune-inflammatory mechanisms as well as bacteria play a major role, in addition to interactions between the arterial wall and blood components. This scenario has promoted nutritional recommendations to enrich different type of foods with plant sterols (PS) because of their cholesterol-lowering effects. In addition to cholesterol, PS can also be oxidized during food processing or storage, and the oxidized derivatives, known as phytosterol oxidation products (POPs), can make an important contribution to the negative effects of both cholesterol and cholesterol oxidation oxides (COPs) in relation to inflammatory disease onset and the development of atherosclerosis. Most current research efforts have focused on COPs, and evaluations of the particular role and physiopathological implications of specific POPs have been only inferential. Appreciation of the inflammatory role described for both COPs and POPs derived from foods also provides additional reasons for safety studies after long-term consumption of PS. The balance and relevance for health of all these effects deserves further studies in humans. This review summarizes current knowledge about the presence of sterol oxidation products (SOPs) in foods and their potential role in inflammatory process and cardiovascular disease.


Assuntos
Doenças Cardiovasculares/etiologia , Alimentos/efeitos adversos , Inflamação/etiologia , Fitosteróis/farmacologia , Aterosclerose/etiologia , Disponibilidade Biológica , Doenças Cardiovasculares/induzido quimicamente , Colesterol/metabolismo , Manipulação de Alimentos , Humanos , Inflamação/induzido quimicamente , Inflamação/metabolismo , Fitosteróis/efeitos adversos , Fitosteróis/metabolismo , Fitosteróis/farmacocinética , Fatores de Risco
15.
Food Chem Toxicol ; 56: 247-53, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23454145

RESUMO

Human diets contain sterol oxidation products that can induce cytotoxic effects, mainly caused by cholesterol oxides. However, phytosterol oxides effects have been less extensively investigated. This study evaluates the production of inflammatory biomarkers (IL-1ß, IL-8, IL-10, TNFα) and the influence of gene expression transporters and enzymes related to cholesterol absorption and metabolism (NPC1L1, ABCG5/8, HMGCoA, ACAT) produced by 7-ketosterols (stigmasterol/cholesterol) in Caco-2 cells. These effects were linked to intracellular signaling pathways by using several inhibitors. Results showed 7-ketostigmasterol to have a greater proinflammatory potential than 7-ketocholesterol. In non-pre-treated cells, only efflux transporters were down-regulated by 7-ketosterols, showing a greater influence upon ABCG5 expression. Cell-pre-incubation with bradykinin induced changes in ABCG expression levels after 7-ketostigmasterol-incubation; however, the energetic metabolism inhibition reduced NPC1L1 expression only in 7-ketocholesterol-incubated cells. In non-pre-treated cells, HMG-CoA was up-regulated by both 7-ketosterols. However, exposure to inhibitors down-regulated the expression levels, mainly in 7-ketocholesterol-incubated cells. While ACAT expression values in non-pre-treated cells were unchanged, exposure to inhibitors caused down-regulation of mRNA levels. These results suggest that internalization and excretion of 7-ketostigmasterol is probably influenced by [Ca]i, which also could mediate HMGCoA activity in POPs metabolism. However, energetic metabolism and reducing equivalents exert different influences upon the 7-ketosterol internalization.


Assuntos
Biomarcadores/metabolismo , Inflamação/patologia , Cetocolesteróis/farmacocinética , Estigmasterol/farmacocinética , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Acetil-CoA C-Acetiltransferase/genética , Acetil-CoA C-Acetiltransferase/metabolismo , Acil Coenzima A/genética , Acil Coenzima A/metabolismo , Anticolesterolemiantes/farmacologia , Transporte Biológico/efeitos dos fármacos , Bradicinina/farmacologia , Células CACO-2 , Regulação para Baixo , Humanos , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Lipoproteínas/genética , Lipoproteínas/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
16.
Infect Genet Evol ; 13: 96-104, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23022714

RESUMO

BACKGROUND: Certain human papillomaviruses (HPVs) are the causative agents of cervical carcinomas in humans. The identification of the link between infection and cancer has resulted in the successful establishment of clinical strategies such as screening or vaccination programs, aiming to prevent this pathology. More than 150 different HPVs have been described and classified and the large majority of them are not related to cancer. The genus Alphapapillomavirus encompasses many PVs, some of which are identified in humans as oncogenic, according to the epidemiological connection between infection and cervical cancer. Variants of some of these "high-risk" HPVs may have an increased involvement in cervical cancer, although definitive data are still wanting. The aim of the present work was to analyze the presence of HPV33, HPV45 and HPV58 variants in cases of cervical cancer. METHODS: Samples from cervical lesions in the context of different cervical cancer surveys were analyzed for presence of HPV DNA. Samples positive for HPV33, HPV45 or HPV58 DNA were selected and the E6/E7 genes were amplified and sequenced. The phylogenetic relationships of these sequences were inferred using an evolutionary placement algorithm and accordingly classified at the variant level. RESULTS: All viral E6/E7 sequences were successfully placed in the classification schemes of the corresponding viruses. For HPV33 (n=23), 45 (n=61) or 58 (n=29), the distribution of variants found in cases of cervical cancer is not a random sample of the corresponding diversity. In all three HPVs, the respective A variants were more prevalent in the viral DNA-positive cases of cervical cancer analyzed. This is the first study trying to discern the phylogenetic connection between variants of the oncogenic HPV33, 45 and 58, and squamous cell carcinoma of the cervix.


Assuntos
Papillomaviridae/classificação , Papillomaviridae/genética , Neoplasias do Colo do Útero/virologia , Feminino , Genótipo , Humanos , Dados de Sequência Molecular , Proteínas E7 de Papillomavirus/genética , Filogenia
17.
Food Chem Toxicol ; 50(9): 3106-13, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22750387

RESUMO

The biological implications of cholesterol oxidation products have been investigated, though research on plant sterol oxidation products is scarce and in some cases contradictory. The cytotoxicity of 7keto(k)-stigmasterol versus 7keto(k)-cholesterol at different concentrations (0-120 µM) and incubation times (4-24h), in intestinal epithelial cells (Caco-2 cells) was evaluated. The 3-[4,5-dimethylthiazol-2-yl]-2,3-diphenyl tetrazolium bromide and neutral red uptake tests, mitochondrial membrane potential (ΔΨm), and relative DNA and RNA contents in the cell cycle phases were determined. Possible interaction effects between 7k-derivatives or non-oxidized stigmasterol were monitored. Endo/lysosomal activity was not impaired by either oxide. 7k-cholesterol showed a deleterious effect upon the mitochondrial compartment after 24h of exposure (120 µM), as well as upon ΔΨm when incubated at all concentrations (12/24h). Only cells incubated with 7k-cholesterol (120 µM) exhibited a decrease in RNA proportion in the G1 population. The presence of 7k-stigmasterol or stigmasterol with 7k-cholesterol reduced the deleterious metabolic effects upon mitochondrial functionality and integrity and the distribution of RNA contents in G1 and G2 phases. A decrease in the G1 phase proportion was detected in cells exposed to mixtures, without alterations in RNA content. The results obtained indicate the absence of 7k-stigmasterol cytotoxicity in Caco-2 cells and its capacity to reduce 7k-cholesterol toxicity.


Assuntos
Colesterol/toxicidade , Intestinos/efeitos dos fármacos , Estigmasterol/toxicidade , Células CACO-2 , Avaliação Pré-Clínica de Medicamentos , Humanos , Intestinos/citologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos
18.
Eur J Clin Microbiol Infect Dis ; 24(7): 488-91, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15997369

RESUMO

Presented here are the results of Legionella urinary antigen testing correlated with patient characteristics and severity of pneumonia (Fine score) in 295 patients diagnosed with Legionella pneumonia in connection with a large outbreak in Murcia, Spain. Overall, the sensitivity of the urinary antigen test was 47.7% (141/295). A statistically significant association was found between the clinical severity of pneumonia and test sensitivity; 85.7% for patients with severe pneumonia versus 37.9% for patients with mild pneumonia (risk ratio, 2.3). Variables significantly associated with test positivity in multivariate analysis were as follows: pre-existing pulmonary disease, body temperature >40 degrees C, leukocytosis and multilobar infiltrates. Patients with mild pneumonia may go undiagnosed if the urinary antigen test is used alone.


Assuntos
Antígenos de Bactérias/urina , Surtos de Doenças , Doença dos Legionários/diagnóstico , Doença dos Legionários/fisiopatologia , Doença dos Legionários/urina , Biomarcadores/urina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Espanha/epidemiologia
19.
Environ Sci Technol ; 39(11): 4307-16, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15984814

RESUMO

Upon contact with water, under a variety of conditions, C60 spontaneously forms a stable aggregate with nanoscale dimensions (d = 25-500 nm), termed here "nano-C60". The color, hydrophobicity, and reactivity of individual C60 are substantially altered in this aggregate form. Herein, we provide conclusive lines of evidence demonstrating that in solution these aggregates are crystalline in order and remain as underivatized C60 throughout the formation/stabilization process that can later be chemically reversed. Particle size can be affected by formation parameters such as rates and the pH of the water addition. Once formed, nano-C60 remains stable in solution at or below ionic strengths of 0.05 I for months. In addition to demonstrating aggregate formation and stability over a wide range of conditions, results suggest that prokaryotic exposure to nano-C60 at relatively low concentrations is inhibitory, indicated by lack of growth (> or = 0.4 ppm) and decreased aerobic respiration rates (4 ppm). This work demonstrates the fact that the environmental fate, distribution, and biological risk associated with this important class of engineered nanomaterials will require a model that addresses not only the properties of bulk C60 but also that of the aggregate form generated in aqueous media.


Assuntos
Fulerenos/química , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/toxicidade , Bactérias Aeróbias/fisiologia , Fulerenos/toxicidade , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica , Nanoestruturas , Concentração Osmolar , Medição de Risco , Esgotos/química , Análise Espectral , Fatores de Tempo
20.
J Am Chem Soc ; 123(35): 8482-95, 2001 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-11525655

RESUMO

Isomers of C(60)H(36) and He@C(60)H(36) have been synthesized by the Birch or dihydroanthracene reduction of C(60) and isolated by preparative high-pressure liquid chromatography. (3)He, (13)C, and (1)H NMR spectroscopic properties were then determined. A comparison of experimental chemical shifts against those computed using density functional theory (B3LYP) with polarized triple- and double-zeta basis sets for He and C,H, respectively, allowed provisional assignment of structure for several isomers to be made. Theoretical calculations have also been carried out to identify low-energy structures. The transfer hydrogenation method using dihydroanthracene gives a major C(60)H(36) isomer and a minor C(60)H(36) isomer with C(3) symmetry as determined by the (13)C NMR spectrum of C(60)H(36) and the (3)He NMR spectrum of the corresponding sample of (3)He@C(60)H(36). In view of the HPLC retention times and the (3)He chemical shifts observed for the Birch and dihydroanthracene reduction products, the two isomers generated by the latter procedure can be only minor isomers of the Birch reduction. A significant energy barrier apparently exists in the dihydroanthracene reduction of C(60) for the conversion of the C(3) and C(1) symmetry isomers of C(60)H(36) to the T symmetry isomer previously predicted by many calculations to be among the most stable C(60)H(36) isomers. Many of the (1)H NMR signals exhibited by C(60)H(36) (and C(60)H(18), previously reported) are unusually deshielded compared to "ordinary" organic compounds, presumably because the unusual structures of C(60)H(36) and C(60)H(18) result in chemical shift tensors with one or more unusual principal values. Calculations clearly show a relationship between exceptionally deshielded protons beta to a benzene ring in C(60)H(18) and C(60)H(36) and relatively long C-C bonds associated with these protons. The additional information obtained from 1D and 2D (1)H NMR spectra obtained at ultrahigh field strengths (up to 900 MHz) will serve as a critical test of chemical shifts to be obtained from future calculations on different C(60)H(36) isomers.

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