SARS-CoV-2 in Mozambican primary school-aged children at Maputo City and Province: a cross-sectional study from a low-income country.

BACKGROUND: Seroprevalence studies provide information on the true extent of infection and capture demographic and geographic differences, indicating the level of immunity against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). We sought to provide local evidence of SARS-CoV-2 exposure in school-aged children during in-class teaching in Maputo City and Province, Mozambique. METHODS: Between August and November 2022, we performed a cross-sectional study in school-aged children in four schools in rural, peri-urban, and urban areas of Maputo City and Province. A point-of-care test was used to evaluate SARS-CoV-2 antigens and anti-SARS-CoV-2-specific immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies. Descriptive statistics were used to estimate the prevalence of the antigens and antibodies. Multiple logistic regression models were used to estimate the adjusted odds ratio (AOR) for the factors associated with anti-SARS-CoV-2 antibodies. RESULTS: A total of 736 school-aged children were analyzed. The prevalence of the SARS-CoV-2 antigen was 0.5% (4/736). The prevalence of SARS-CoV-2 antigens was 0.0% (0/245), 0.8% (2/240) and 0.8% (2/251), in the rural, peri-urban and urban areas respectively. The overall seroprevalence of the anti-SARS-CoV-2 antibodies (IgG or IgM) was 80.7% (594/736). In rural area anti-SARS-CoV-2 IgG or IgM antibodies were detected in 76.7% (188/245), while in peri-urban area they were detected in 80.0% (192/240) and in urban area they were detected in 85.3% (214/251). In the adjusted logistic regression model, school-aged children from the urban area were more likely to have anti-SARS-CoV-2 IgG or IgM antibodies than were school-aged children from the rural area (adjusted odds ratio: 1.679; 95% CI: 1.060-2.684; p-value = 0.028). CONCLUSIONS: During the in-class teaching period, active SARS-CoV-2 cases in school-aged children were observed. More than half of the school-aged children were exposed to SARS-CoV-2, and SARS-CoV-2 was significantly more common in the schools at the urban area than in the school in the rural area at Maputo City and Province.

Avaliação de diferentes métodos educativos em saúde bucal em crianças na faixa etária de 7 a 10 anos de idade / Evaluation of different educational methods in oral health in children aged 7-10 years old

Objetivo: avaliar a influência de estratégias educativas em saúde bucal em crianças de 7 a 10 anos de idade, provenientes de uma escola pública da cidade de Araras ? SP. Materiais e método: participaram do estudo 112 crianças que foram aleatoriamente divididas em quatro grupos. Cada grupo participou de uma atividade educativa diferente, dentre elas, teatro (n=15), gincana (n=19), história em quadrinhos (n=22) e palestra (n=26). Todas as crianças responderam a um questionário contendo vinte questões de múltipla escolha relacionadas à saúde bucal, aplicado duas semanas antes da introdução dos métodos educativos e imediatamente após o desenvolvimento desses. Realizou-se estatística descritiva por meio de frequências absolutas e relativas. Para a comparação entre os acertos de cada questão antes e após a realização de cada atividade educativa, aplicou-se o teste estatístico de Mc Nemar no nível de significância de 5%. Resultados: a ?história em quadrinhos? foi a atividade educativa com maior número de questões com acertos após a realização dessa. Não houve diferença estatística significativa nos acertos antes e depois da atividade educativa ?gincana? para nenhuma das questões. Conclusão: a história em quadrinhos apresentou os melhores resultados para a amostra estudada. Entretanto, os métodos educativos apresentados, de maneira geral, não influenciaram no conhecimento adquirido da população estudada.

HOXB5 expression in oral squamous cell carcinoma.

UNLABELLED: Human HOX genes encode transcription factors that act as master regulators of embryonic development. They are important in several processes such as cellular morphogenesis and differentiation. The HOXB5 gene in particular has been reported in some types of neoplasm, but not in oral cancer. OBJECTIVE: The present study investigated the expression of HOXB5 in oral squamous cell carcinoma (SCC) and in non-tumoral adjacent tissues, focusing on verifying its possible role as a broad tumor-associated gene and its association with histopathological and clinical (TNM) characteristics. MATERIAL AND METHODS: RT-PCR was performed to amplify HOXB5 mRNA in 15 OSCCs and adjacent non-tumoral epithelium. A possible association with TNM and histopathologic data was verified by the chi-square and post-hoc t-test. RESULTS: HOXB5 was amplified in 60% non-tumoral epithelium and in 93.3% carcinomas. No statistically significant differences were found regarding the HOXB5 mRNA expression and TNM or histological grade. CONCLUSION: HOXB5 is expressed in OSCCs and its role in cancer progression should be further investigated.

HOXB5 expression in oral squamous cell carcinoma

Human HOX genes encode transcription factors that act as master regulators of embryonic development. They are important in several processes such as cellular morphogenesis and differentiation. The HOXB5 gene in particular has been reported in some types of neoplasm, but not in oral cancer. OBJECTIVE: The present study investigated the expression of HOXB5 in oral squamous cell carcinoma (SCC) and in non-tumoral adjacent tissues, focusing on verifying its possible role as a broad tumor-associated gene and its association with histopathological and clinical (TNM) characteristics. MATERIAL AND METHODS: RT-PCR was performed to amplify HOXB5 mRNA in 15 OSCCs and adjacent non-tumoral epithelium. A possible association with TNM and histopathologic data was verifed by the chi-square and post-hoc t-test. RESULTS: HOXB5 was amplifed in 60 percent non-tumoral epithelium and in 93.3 percent carcinomas. No statistically signifcant differences were found regarding the HOXB5 mRNA expression and TNM or histological grade. CONCLUSION: HOXB5 is expressed in OSCCs and its role in cancer progression should be further investigated.

In situ hybridization detection of homeobox genes reveals distinct expression patterns in oral squamous cell carcinomas.

AIMS: To analyse the expression of three homeobox genes (HOXA7, PITX1 and PRRX1) in oral squamous cell carcinomas (OSCC) and the relationship of such expression to certain distinct histopathological features of OSCC and in comparison to adjacent non-neoplastic epithelium (NT). METHODS AND RESULTS: Digoxigenin-labelled riboprobes that are specific for each homeobox gene were generated and in situ hybridization was carried out on frozen sections. In NT samples, HOXA7 and PITX1 transcripts were found more frequently in all epithelial layers, while PRRX1 was expressed in the basal layer. With OSCC samples, expression of the three genes was associated with all histological features. However, the HOXA7 and PITX1 signals were more intense in sheets and nests and PRRX1 in small nests and isolated cells. CONCLUSION: HOXA7, PIXT1 and PRRX1 homeobox genes have different patterns of expression in OSCC depending on its histological features.

Detection of TGIF1 homeobox gene in oral squamous cell carcinoma according to histologic grading.

OBJECTIVE: TGIF1 homeobox gene involvement in oral cancer has not yet been investigated. This study analyzed the expression of TGIF1 transcripts and protein in oral squamous cell carcinoma (OSCC). STUDY DESIGN: Snap-frozen samples from 16 patients were taken from both OSCC and nontumoral adjacent epithelium (NT) for in situ hybridization (ISH). Forty-six paraffin-embedded samples of OSCC were submitted to immunohistochemistry (IHC). A descriptive analysis of the transcript signal detection was accomplished, and TGIF1 immunoexpression was carried out considering protein levels, localization, and cellular differentiation. RESULTS: ISH reactions showed TGIF1 transcripts with a signal that was frequently intense in NT, and generally weak in OSCC, and that had stronger transcript signal in well-differentiated areas of OSCC when compared with poorly differentiated ones. IHC reactions had poorly differentiated cases associated with TGIF1 protein expression in both the nucleus and cytoplasm (P = .05, Fisher test). CONCLUSIONS: TGIF1 gain or loss of function might possibly play a role in oral cancer cell differentiation.

Central mucoepidermoid carcinoma: Report of a case with 11 years’ evolution and peculiar macroscopical and clinical characteristics

Central mucoepidermoid carcinomas (CMC) are uncommon tumours, comprising 2-3% of all mucoepidermoid carcinomas reported. They have been reported in patients of all ages, ranging from 1 to 78-years, with the overwhelming majority occurring in the 4th and 5th decades of life. They are histologically low-grade cancers, usually affecting the mandible as uniocular or multiocular radiographic lesions. The authors report a case of CMC of the mandible with a long evolution, and peculiar clinical and macroscopical features related with the long term evolution of the disease. A 53-year-old male patient had expansion of buccal and lingual cortices of the anterior region of the mandible, covered by ulcerated mucosa, with 11 years evolution. An incisional biopsy was performed, and the histopathological findings confirm low-grade mucoepidermoid carcinoma. The patient was treated with a mandibulectomy, followed by supraomohyoid neck dissection. There was no evidence of local recurrence, regional or distant metastasis revealed; and the patient was alive and without disease after a follow- up interval of 36 months (AU)

Central mucoepidermoid carcinoma: report of a case with 11 years' evolution and peculiar macroscopical and clinical characteristics.

Central mucoepidermoid carcinomas (CMC) are uncommon tumours, comprising 2-3% of all mucoepidermoid carcinomas reported. They have been reported in patients of all ages, ranging from 1 to 78-years, with the overwhelming majority occurring in the 4th and 5th decades of life. They are histologically low-grade cancers, usually affecting the mandible as uniocular or multiocular radiographic lesions. The authors report a case of CMC of the mandible with a long evolution, and peculiar clinical and macroscopical features related with the long term evolution of the disease. A 53-year-old male patient had expansion of buccal and lingual cortices of the anterior region of the mandible, covered by ulcerated mucosa, with 11 years evolution. An incisional biopsy was performed, and the histopathological findings confirm low-grade mucoepidermoid carcinoma. The patient was treated with a mandibulectomy, followed by supraomohyoid neck dissection. There was no evidence of local recurrence, regional or distant metastasis revealed; and the patient was alive and without disease after a follow-up interval of 36 months.

Expressão do RNA mensageiro de genes HOX em linhagens celulares de carcinomas epidermoides de cabeça e pescoço / HOX genes mRNA expression in head and neck squamous cell carcinoma cell lineages

Os genes HOX são importantes para o controle do desenvolvimento embrionário e regulam aspectos da morfogênese e diferenciação celular. A associação entre os genes HOX e o processo da oncogênese tem sido verificada em casos de carcinomas de cólon, pele, rim, pulmão, mama, leucemias e outros tipos de câncer. O objetivo deste trabalho foi verificar a expressão de genes HOX em linhagens celulares de carcinomas epidermoides de cabeça e pescoço. Para tanto, utilizamos a técnica RT-PCR para analisar a expressão de três grupos de genes HOX em linhagens celulares de carcinomas epidermoides de cabeça e pescoço: HN-6, HN-19, HN-30 e HN-31, utilizando-se os primeiros degenerados HOX1, HOX2 e HOX3 e coamplificação com o gene constitutivo da β-actina. Material de gengiva humana e embrião de camundongo foram utilizados como controle de expressão do gene HOX. Os resultados obtidos mostraram que a expressão dos genes HOX apresentou padrão semelhante aos controles utilizados. Houve, porém, subexpressão do grupo HOX1 nas linhagens HN-6 e HN-19 e superexpressão do grupo HOX-2 na linhagem HN-31. Esses achados nos permitem levantar a hipótese de que os genes HOX podem participar das alterações moleculares observadas em carcinomas epidermoides de cabeça e pescoço.

Hibridização in situ com sonda não-radioativa para mRNA: princípios e aplicações em patologia / In situ hybridization with non-radioactive riboprobes: principles and applications in pathology

A técnica de hibridização in situ (ISH) tem sido usada para identificar mRNA (ou DNA) em amostras de tecido de material humano e animal. Embora uma série de protocolos para essa técnica seja utilizada, as descrições não são bem detalhadas. O objetivo deste trabalho é descrever a reação de hibridização in situ em tecido fresco e sua aplicação em patologia, tornando mais compreensível essa técnica tão importante, que possibilita observar a localização tecidual e a expressão temporal e espacial dos transcritos de um determinado gene (mRNA). Resultados de reações com as ribossondas PITX1, SHH e WNT-5A, realizadas em amostras de tecido congelado, são apresentados.

In situ hybridization (ISH) has been used to identify mRNA (or DNA) in fresh tissue samples of humans and animals. Several protocols describing this technique are available, although its description is not usually detailed enough. The present work describes in situ hybridization reaction on fresh tissue in a way to make understandable this important technique, which allows verifying the cellular localization, and the spatial and temporal expression, of gene transcripts (mRNA). Results with PITX1, TGIF, SHH and WNT-5A riboprobes, in fresh tissue samples, are presented.

TP53 mutations in salivary gland neoplasms

Vários estudos mostram que a perda da função do gene TP53 desempenha um importante papel na gênese de diversas neoplasias, incluindo as neoplasias de glândula salivar. Assim, o objetivo deste estudo foi avaliar a presença de mutações no gene TP53 em neoplasias de glândula salivar. Para isso, DNA genômico foi extraído de casos de adenoma pleomórfico (AP), carcinoma em adenoma pleomórfico (CAP), carcinoma mucoepidermóide (CME), carcinoma adenóide cístico (CAC) e adenocarcinoma polimorfo de baixo grau de malignidade (APBG) emblocados em parafina. Foi realizada amplificação pela técnica da PCR dos exons 5 a 8 e em seguida a SSCP (análise de conformação de fita simples). Foi observada alteração na mobilidade das bandas em 9 das 18 neoplasias estudadas, principalmente nos exons 5 e 8. Esses achados sugerem que mutações no gene TP53 estão relacionadas à patogênese das neoplasias de glândula salivar e que os exons 5 e 8 estão mais freqüentemente envolvidos.

TP53 mutations in salivary gland neoplasms.

Many studies have demonstrated that loss of TP53 gene function has an important role in the genesis of many neoplasms, including salivary gland neoplasms. The purpose of this study was to examine the mutation profile of the TP53 gene in salivary gland neoplasms. Genomic DNA was extracted from paraffin-embedded tissues of pleomorphic adenoma, carcinoma in pleomorphic adenoma, mucoepidermoid carcinoma, adenoid cystic carcinoma and polymorphous low grade adenocarcinoma. Exons 5 to 8 of the TP53 gene were amplified by polymerase chain reaction (PCR) to perform single-stranded conformational polymorphism (SSCP) analysis. Band shifting was observed in exons 5, 6 and 8 in 9 out of 18 neoplasms. The results of this study suggest that mutations in TP53 gene are related to salivary gland neoplasms pathogenesis and that exons 5 and 8 are most frequently involved.

Análise da presença de transcritos dos genes HOXA7, HOXC6 e TGIF em carcinomas epidermóides de boca / Analysis of presence of HOXA7, HOC6 and TGIF transcripts in oral squamous cell carcinoma

Os genes homeobox são uma família de genes reguladores que são vitais para vários aspectos do crescimento e diferenciação celular. Recentemente, implicações dos genes HOXA7, HOXC6 e TGIF na gênese e progressão tumoral vêm sendo verificadas. Entretanto, o envolvimento desses genes em carcinomas epidermóides (CE) de boca ainda não foi demonstrado. A possível presença de transcritos dos genes HOXA7, HOXC6 e TGIF em carcinomas epidermóides de boca e em tecidos não tumorais adjacentes (TN) foi analisada. Os transcritos dos genes foram amplificados por RT-PCR e sua localização celular determinada por hibridização in situ (ISH) com sondas de mRNA específicas. A amplificação do HOXA7 foi observada em 70 por cento dos casos sendo 15 por cento apenas nas amostras TN, 45 por cento somente nos CEs e 10 por cento em ambos tecidos. Nenhuma amplificação do HOXC6 foi observada. O TGIF foi amplificado em 80 por cento dos casos, sendo 5 por cento somente nas amostras TN, 20 por cento nos CEs e 55 por cento em ambos tecidos. Análises estatísticas mostraram que não havia diferença significante entre a amplificação do transcrito HOXA7 ou TGIF e o tipo de tecido analisado. Além disso, nenhuma associação entre a amplificação dos transcritos nas amostras CE e os aspectos clínicos foi observada. O sinal de hibridização in situ foi similar para os transcritos HOXA7 e TGIF. Nas amostras TN o sinal da ISH foi intenso no epitélio, ora disperso sendo mais proeminente na camada espinhosa ora mais proeminente nas camadas basais e suprabasais. Nos CEs os transcritos foram localizados por toda neoplasia sendo que o sinal era menor em áreas menos diferenciadas. Esses resultados mostram que o HOXC6 não está envolvido com a carcinogênese oral enquanto que a presença dos transcritos HOXA7 e TGIF principalmente em regiões bem diferenciadas dos carcinomas epidermóides de boca sugere uma participação desses genes nesta neoplasia