Evaluation of DNA Recombinant Methodologies for the Diagnosis of Plasmodium falciparum and their Comparison with the Microscopy Assay

Since 1984, DNA tests based on the highly repeated subtelomeric sequences of Plasmodium falciparum (rep 20) have been frequently used in malaria diagnosis. Rep 20 is very specific for this parasite, and is made of 21 bp units, organized in repeated blocks with direct and inverted orientation. Based in this particular organization, we selected a unique consensus oligonucleotide (pf-21) to drive a PCR reaction coupled to hybridization to non-radioactive labeled probes. The pf-21 unique oligo PCR (pf-21-I) assay produced DNA amplification fingerprints when was applied on purified P. falciparum DNA samples (Brazil and Colombia), as well as in patient's blood samples from a large area of Venezuela. The performance of the Pf-21-I assay was compared against Giemsa stained thick blood smears from samples collected at a malaria endemic area of the Bolívar State, Venezuela, at the field station of Malariología in Tumeremo. Coupled to non-radioactive hybridization the pf-21-I performed better than the traditional microscopic method with a r=1.7:1. In the case of mixed infections the r value of P. falciparum detection increased to 2.5:1. The increased diagnostic sensitivity of the test produced with this homologous oligonucleotide could provide an alternative to the epidemiological diagnosis of P. falciparum being currently used in Venezuela endemic areas, where low parasitemia levels and asymptomatic malaria are frequent. In addition, the DNA fingerprint could be tested in molecular population studie

Manifestações orais associada ao papilomavírus humano (hpv) conceitos atuais: revisão bibliográfica Oral manifestations related to papillomavirus (hpv)

O papilomavírus (HPV) é um DNA vírus do grupo papovavírus, que é altamente transmissível sexualmente, sendo freqüente na região ano-genital e raro na mucosa oral. A sua implantação oral pode ser por auto-inoculação ou pelo contato oro-sexual. As manifestações orais associadas ao HPV são: papiloma, condiloma acuminado, verruga vulgar, hiperplasia epitelial focal, leucoplasias, líquen plano e carcinoma. O diagnóstico é dado pelo exame da lesão e confirmado pela biópsia, com a identificação do tipo de HPV pelas técnicas de biologia molecular (captura híbrida e PCR). O tratamento, dependendo da lesão, pode ser clínico e/ou cirúrgico, obtendo assim a cura clínica, pois o vírus permanece no epitélio da mucosa mesmo após o tratamento.<br>The human papillomavirus (HPV) is a DNA virus, of the papovavirus group, that is highly sexually transmittable. It is common in the anal and genital parts and rarely in the oral mucosa. The oral implantation can be by self-inoculation or by oral-sexual contact. The oral manifestations related to HPV are: papilloma, condyloma acuminatum, verruca vulgaris, focal epithelial hyperplasia, leukoplasia, lichen planus, and the squamous cell carcinoma. The diagnosis is performed by lesion exam and confirmed by biopsy, showing the HPV genotype by molecular biology techniques (hybrid capture and PCR). The treatment, depending on the lesion, can be clinical or surgical, allowing clinical cure, because the virus remains in the epithelium of the mucosa even after the treatment

Carcinoma de células escamosas oral - contribuição de vírus oncogênicos e alguns marcadores moleculares no desenvolvimento e prognóstico da lesão: uma revisão Oral squamous cell carcinoma - contribution of oncogenic virus and some molecular markers in the development and prognosis of the lesion: a review

O carcinoma de células escamosas oral é um evento de muitas etapas, cuja incidência cresce continuamente, particularmente em jovens, numa amplitude que não pode ser completamente explicada pelo aumento da exposição a fatores de risco, como o tabaco e o álcool. Recentes investigações moleculares sugerem que existem múltiplos eventos genéticos, e vírus oncogênicos que são capazes de alterar as funções normais de oncogenes e genes de supressão tumoral. O objetivo deste artigo foi revisar o conhecimento atual sobre o papel do papilomavírus humano (HPV), Epstein-Barr vírus (EBV), P53 e telomerase no desenvolvimento e prognóstico do carcinoma de células escamosas oral.<br>Oral squamous cell carcinoma is a multistep event that continues to increase in incidence, particularly in the young, and to an extent that cannot be fully explained by increased exposure to known risk factors, as tobacco or alcohol. Recent molecular investigations suggest that there are multiple genetic events, and oncogenic virus that are able to alter the normal functions of oncogenes and tumor suppressor genes. The aim of the present article was to review the current knowledge on the role of Human papillomavirus (HPV), Epstein-Barr virus (EBV), P53 and telomerase in the development and prognosis of the oral squamous cell carcinoma

Prevalência de achados sugestivos de papilomavírus humano (HPV) em biópsias de carcinoma espinocelular de cavidade oral e orofaringe: estudo preliminar Prevalence of histological findings of human papillomavirus (HPV) in oral and oropharyngeal squamous cell carcinoma biopsies: preliminary study

O papilomavírus humano (HPV) é universalmente aceito como agente causal do câncer de colo uterino e, recentemente, vem se especulando sobre sua possível relação com câncer oral e de orofaringe. O carcinoma espinocelular (CEC) oral representa 90% de todos os tumores malignos que afetam a cavidade bucal. Estudos sobre a prevalência de HPV em pacientes com CEC variam de 0 a 100%. O efeito citopático viral mais conhecido é a coilocitose, considerado "critério maior" na infecção pelo HPV do ponto de vista histopatológico. OBJETIVO: O objetivo deste estudo foi verificar a prevalência de achados sugestivos de HPV - coilocitose - em CEC oral e de orofaringe. FORMA DE ESTUDO: coorte transversal. MATERIAL E MÉTODO: Foram examinadas no microscópio 20 lâminas com o diagnóstico de CEC de cavidade oral ou orofaringe sendo que em 15 delas foi encontrada coilocitose, correspondendo a 75%. RESULTADO: Apesar de termos conhecimento que o método com maior sensibilidade atual para pesquisa de HPV ser a reação de polimerase em cadeia (PCR), iniciamos esta pesquisa com a investigação de coilocitose, o que é muito sugestivo de infecção por HPV. CONCLUSÃO: O estudo em questão trata-se de um projeto-piloto pois será dada continuidade a esta pesquisa através da realização de PCR a fim de confirmar a alta prevalência de infecção por HPV em CEC oral e de orofaringe.<br>Human papillomavirus (HPV) is considered to be an etiologic agent of cervical cancer and, recently its relation to oral and oropharyngeal cancer has also been investigated. Oral squamous cell carcinoma (SCC) represents 90% of all malignant tumors that affect the oral cavity. The prevalence of HPV in patients with SCC ranges from 0 to 100%. The most known viral cytopathic effect is koilocytosis, considered to be a major characteristic of HPV infection. AIM: The aim of this study was to verify the prevalence of some peculiar characteristics of HPV - koilocytosis - in oral and oropharyngeal SCC. STUDY DESIGN: transversal cohort. MATERIAL AND METHOD: Twenty slides with oral and/or oropharyngeal SCC were examined under microscopy. RESULTS: in 15 of them, koilocytosis was found, amounting to 75%. Although we know that polymerase chain reaction (PCR) is the method with the best sensitivity for HPV detection, we began this research looking for koilocytosis, which is highly suggestive of HPV infection. CONCLUSION: This study is a trial project and we will continue this research with PCR measures to confirm this high prevalence of HPV infection in oral and oropharyngeal SCC

Human papillomavirus (HPV) detection in lip squamous cell carcinoma: correlation with clinical aspects and risk factors Detecção do papilomavírus humano (HPV) em carcinoma espinocelular de lábio: correlação com aspectos clínicos e fatores de risco

Human papillomavirus (HPV) is associated with a wide spectrum of lesions in humans, and it has been linked to oral carcinogenesis. The aim of this study was to investigate the presence of HPV DNA in patients with lip squamous cell carcinoma and to correlate it with clinical characteristics and risk factors. We studied 33 patients with lip squamous cell carcinomas. Of these, 30 were positive for human beta globin gene and tested for HPV DNA, using polymerase chain reaction in two steps (PCR and nPCR) with MY11/MY09 and GP5+/GP6+ primers. HPV DNA was detected in 43.33% of patients analyzed. There was no association with the risk factors analyzed.<br>O papilomavírus humano (HPV) está associado a um largo espectro de lesões em humanos e tem sido ligado à carcinogênese oral. O objetivo deste estudo foi investigar a presença do DNA do HPV em pacientes com carcinoma espinocelular de lábio e correlacioná-la com aspectos clínicos e fatores de risco. Foram estudados 33 pacientes com carcinoma espinocelular de lábio. Destes, 30 pacientes foram positivos para o gene da beta-globina humana e então foram testados para o DNA do HPV com uso da reação em cadeia de polimerase em duas etapas (PCR e nPCR) com os oligonucleotídeos iniciadores MY11/MY09 e GP5+/ GP6+. O DNA do HPV foi detectado em 43,33% dos 30 pacientes analisados. Não houve associação com os fatores de risco analisados