Conjunctival melanoma following cornea transplant from a cancer donor: A case report.

Purpose: Conjunctival melanoma is a rare ocular tumor. We report a case of ocular conjunctival melanoma during topical immunosuppression, after a corneal transplant from a donor with metastatic melanoma. Observation: A 59-year-old white male presented with a progressive nonpigmented conjunctival lesion in his right eye. He had previously undergone two penetrating keratoplasties, and he was being treated with topical immunosuppression with 0.03% tacrolimus (Ophthalmos Pharma; Sao Paulo, SP/Brazil). The histopathology evaluation revealed the nodule to be a conjunctival epithelioid melanoma. The donor's death cause was disseminated melanoma. Conclusion and importance: The correlation between cancer and systemic immunosuppression after a solid organ transplant is widely known. The local influence, however, has not been reported. In this case, a causal relationship was not established. The correlation between conjunctival melanoma, exposure to topical tacrolimus immunosuppressive therapy, and the malignance characteristic of donor cornea should be better evaluated.

Promoting adequate and healthy food in early childhood education: a systematic review / Promoção da alimentação adequada e saudável na educação infantil: uma revisão sistemática

Abstract Objectives: to identify and describe the characteristics of studies that address the promotion of adequate and healthy food in early childhood education units and their repercussions on the school community. Methods: the search and selection were performed according to the PRISMA recommendations in the Medline databases via OVID, EMBASE and LILACS. Data extraction took placeusing a table developed by the authors. The evaluation of the quality of the evidence of the studies was carried out through the risk of bias using an adapted scale. Result: twelve articles that met the eligibility criteria were selected. All studies were applied in public or private educational institutions with a median of 236 participants. In the analysis of food and nutrition education activities, the most adopted with preschoolers were playful; with the parents it was the meetings and counseling; and with the professionals it was the training. The methodological qualification of the studies was considered low, which may be related to their limitations included in this review, mainly due to the types of designs adopted, the time and lack of continuity of interventions and sample size. Conclusion: food and nutrition education activities seem to be a promising strategy in knowledge, adoption of healthy eating practices and transmission of values in the school community.

Resumo Objetivos: identificar e descrever as características de estudos que abordam a promoção da alimentação adequada e saudável em unidades de educação infantil e suas repercussões na comunidade escolar. Métodos: a busca e seleção foram realizadas segundo as recomendações do PRISMA nas bases de dados Medline via OVID, EMBASE e LILACS. A extração de dados ocorreu utilizando uma tabela elaborada pelas autoras. A avaliação da qualidade das evidências dos estudos foi realizada por meio do risco de viés utilizando uma escala adaptada. Resultados: foram selecionados 12 artigos que atenderam aos critérios de elegibilidade. Todos os estudos foram aplicados em instituições de ensino públicas ou privadas com uma mediana de 236 participantes. Na análise das atividades de educação alimentar e nutricional, as mais adotadas com os pré-escolares foram as lúdicas; com os pais foram as reuniões e aconselhamentos; e com os profissionais foram as capacitações. A qualificação metodológica dos estudos foi considerada baixa, podendo estar relacionada às limitações dos próprios estudos incluídos nesta revisão, principalmente pelos tipos de desenhos adotados, o tempo e a falta de continuidade das intervenções e tamanho amostrai. Conclusão: atividades de educação alimentar e nutricional parecem ser uma estratégia promissora na disseminação do conhecimento, adoção de práticas alimentares saudáveis e transmissão de valores na comunidade escolar.

Corneal Graft Rejection After Inactivated SARS-CoV-2 Vaccine: Case Report.

PURPOSE: Our aim was to report the case of endothelial corneal allograft rejection after inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine with an atypical presentation. METHODS: This was a case report. RESULTS: A 63-year-old woman with previous penetrating keratoplasty and laser in situ keratomileusis presented with clinical signs of endothelial corneal graft rejection 24 hours after CoronaVac (SinoVac Biotech, Beijing/China) vaccine. Slitlamp examination showed corneal edema and interface fluid accumulation. It was partially resolved after treatment with topical corticosteroids and polydimethylsiloxane. CONCLUSIONS: Corneal allograft rejection was already reported after another SARS-CoV-2 vaccine. This is the first report in the literature describing a possible association with inactivated SARS-CoV-2 vaccine and corneal allograft rejection, especially with laser in situ keratomileusis interface fluid accumulation presentation. Ophthalmologists should be aware of this potential complication.

SARS-CoV-2 genomic characterization and clinical manifestation of the COVID-19 outbreak in Uruguay

COVID-19 is a respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and declared by the World Health Organization a global public health emergency. Among the severe outbreaks across South America, Uruguay has become known for curtailing SARS-CoV-2 exceptionally well. To understand the SARS-CoV-2 introductions, local transmissions, and associations with genomic and clinical parameters in Uruguay, we sequenced the viral genomes of 44 outpatients and inpatients in a private healthcare system in its capital, Montevideo, from March to May 2020. We performed a phylogeographic analysis using sequences from our cohort and other studies that indicate a minimum of 23 independent introductions into Uruguay, resulting in five major transmission clusters. Our data suggest that most introductions resulting in chains of transmission originate from other South American countries, with the earliest seeding of the virus in late February 2020, weeks before the borders were closed to all non-citizens and a partial lockdown implemented. Genetic analyses suggest a dominance of S and G clades (G, GH, GR) that make up >90% of the viral strains in our study. In our cohort, lethal outcome of SARS-CoV-2 infection significantly correlated with arterial hypertension, kidney failure, and ICU admission (FDR < 0.01), but not with any mutation in a structural or non-structural protein, such as the spike D614G mutation. Our study contributes genetic, phylodynamic, and clinical correlation data about the exceptionally well-curbed SARS-CoV-2 outbreak in Uruguay, which furthers the understanding of disease patterns and regional aspects of the pandemic in Latin America.

Assessment of the use and quick preparation of saliva for rapid microbiological diagnosis of COVID-19.

The objective of this study was to assess the performance of direct real time RT-PCR detection of SARS-CoV-2 in heated saliva samples, avoiding the RNA isolation step. Oropharyngeal and nasopharyngeal swabs together with saliva samples were obtained from 51 patients clinically diagnosed as potentially having COVID-19. Two different methods were compared: 1. RNA was extracted from 500 l of sample using a MagNA Pure Compact Instrument with an elution volume of 50l and 2. 700{micro}L of saliva were heat-inactivated at 96{degrees}C for 15 minutes, and directly subjected to RT-PCR. One step real time RT-PCR was performed using 5 l of extracted RNA or directly from 5 l of heated sample. RT-PCR was performed targeting the SARS-CoV-2 envelope (E) gene region. Diagnostic performance was assessed using the results of the RT-PCR from nasopharyngeal and oropharyngeal swabs as the gold standard. The overall sensitivity, specificity, positive and negative predictive values were 81.08%, 92.86%, 96.77% and 65.00%, respectively when RNA extraction was included in the protocol with saliva, whereas sensitivity, specificity, positive and negative predictive values were 83.78%, 92.86%, 68.42% and 96.88%, respectively, for the heat-inactivation protocol. However, when the analysis was performed exclusively on saliva samples with a limited time from the onset of symptoms (<9 days, N=28), these values were 90%, 87.5%, 44% and 98.75% for the heat-inactivation protocol. The study showed that RT-PCR can be performed using saliva in an RNA extraction free protocol, showing good sensitivity and specificity.

Correção cirúrgica monocular em exotropias de grande ângulo: estudo de casos / Monocular surgical correction in wide-angle exotropias: case studies

Estrabismo consiste em uma enfermidade oftalmológica de alta prevalência na população mundial. A correção cirúrgica binocular, técnica que envolve a abordagem de três a quatro músculos extraoculares, é amplamente utilizada na terapêutica dos estrabismos de grande ângulo. Entretanto, a cirurgia monocular, realizada a partir de recuos e ressecções de maior amplitude, quando aplicada em pacientes amblíopes, possui importantes vantagens em relação à técnica binocular, tais como a preservação do olho dominante e a redução do tempo da cirurgia. Neste estudo, são descritos quatro casos de pacientes amblíopes portadores de exotropia de grande ângulo submetidos à correção cirúrgica monocular. Os pacientes apresentaram desvios oculares prévios equivalentes a 60, 65, 70 e 80 dioptrias prismáticas (Δ). Todos foram submetidos à cirurgia de recuo-ressecção através de recuo mínimo de 8 milímetros (mm) em músculo reto lateral e ressecção mínima de 9 mm em reto medial. Após três meses de acompanhamento, um paciente apresentou-se ortotrópico, enquanto os demais apresentaram desvios residuais de 10 a 12 (Δ). Observou-se limitação na abdução ocular no pós-operatório inicial de dois pacientes. Nenhum paciente apresentou restrição ao teste das versões e duções após três meses de acompanhamento. A cirurgia de recuo-ressecção monocular tem determinado importante relevância no tratamento dos estrabismos horizontais de grande ângulo, mostrando-se uma opção cirúrgica clinicamente factível. Contudo, deve-se estar atento às possíveis complicações que podem relacionar-se à maior amplitude das intervenções musculares (AU)

Strabismus is an ophthalmologic disease of high prevalence in the world population. Binocular surgical correction, a technique that involves approaching three to four extraocular muscles, is widely used in the treatment of wide-angle strabismus. However, monocular surgery, performed from wider recoils and resections, when applied to amblyopic patients, has important advantages over the binocular technique, such as preservation of the dominant eye and reduction of surgery time. In this study, four cases of amblyopia patients with large angle exotropia submitted to monocular surgical correction are described. The patients had previous ocular deviations equivalent to 60, 65, 70 and 80 prismatic diopters. All patients underwent recoil-resection surgery with minimal recoil of 8 mm in the lateral rectus muscle and minimal resection of 9 mm in the medial rectus. After three months of follow-up, one patient was orthoptic, while the others had residual deviations of 10 to 12 diopters. Limitation of ocular abduction in the initial postoperative period was observed in two patients. No patient had a restriction on the test of the versions and ductions after three months of follow-up. The monocular recoil-resection surgery has acquired an important relevance in the treatment of horizontal wide-angle strabismus, proving to be a clinically feasible surgical option. However, one should be aware of the possible complications that may be related to the greater amplitude of the muscular interventions (AU)

Role of double-balloon enteroscopy in malignant small bowel tumors.

AIM: To assess the double-balloon enteroscopy (DBE) role in malignant small bowel tumors (MSBT). METHODS: This is a retrospective descriptive study performed in a single center. All consecutive patients who underwent a DBE with final diagnosis of a malignant neoplasm from 2004 to 2014 in our referral center were included. Patient demographic and clinical pathological characteristics were recorded and reviewed. MSBT diagnosis was achieved either by DBE directed biopsy with multiple tissue sampling, endoscopic findings or histological analysis of surgical specimen. We have analyzed double-balloon enteroscopy impact in outcome and clinical course of these patients. RESULTS: Of 627 patients, 28 (4.5%) (mean age = 60 ± 17.3 years) underwent 30 procedures (25 anterograde, 5 retrograde) and were diagnosed of a malignant tumor. Patients presented with obscure gastrointestinal bleeding (n = 19, 67.9%), occlusion syndrome (n = 7, 25%) and diarrhea (n = 1, 3.6%). They were diagnosed by DBE biopsy (n = 18, 64.3%), histological analysis of surgical specimen (n = 7, 25%) and unequivocal endoscopic findings (n = 2, 7.1%). Gastrointestinal stromal tumor (n = 8, 28.6%), adenocarcinoma (n = 7, 25%), lymphoma (n = 4, 14.3%), neuroendocrine tumor (n = 4, 14.3%), metastatic (n = 3, 10.7%) and Kaposi sarcoma (n = 1, 3.6%) were identified. DBE modified outcome in 7 cases (25%), delaying or avoiding emergency surgery (n = 3), modifying surgery approach (n = 2) and indicating emergency SB partial resection instead of elective approach (n = 2). CONCLUSION: DBE may be critical in the management of MSBT providing additional information that may be decisive in the clinical course of these patients.

Electrophysiological Studies and Radiofrequency Ablations in Children and Adolescents with Arrhythmia / Estudos Eletrofisiológicos e Ablações com Radiofrequência em Crianças e Adolescentes com Arritmia

Background: Radiofrequency ablation is the standard non-pharmacological treatment for arrhythmias in pediatric patients. However, arrhythmias and their associated causes have particular features in this population. Objective: To analyze the epidemiological characteristics and findings of electrophysiological diagnostic studies and radiofrequency ablations in pediatric patients referred to the Electrophysiology Unit at Instituto de Cardiologia do Rio Grande do Sul, in order to characterize the particularities of this population. Methods: Cross-sectional study with 330 electrophysiological procedures performed in patients aged less than 20 years between June 1997 and August 2013. Results: In total, 330 procedures (9.6% of the overall procedures) were performed in patients aged less than 20 years (14.33 ± 3.25 years, age range 3 months to 19 years), 201 of which were males (60.9%). A total of 108 (32.7%) electrophysiological diagnostic studies were performed and of these, 48.1% showed abnormal findings. Overall, 219 radiofrequency ablations were performed (66.3%) with a success rate of 84.8%. The presence of an accessory pathway was the most prevalent finding, occurring in 158 cases (72.1%), followed by atrioventricular nodal reentrant tachycardia (16.8%), typical atrial flutter (3.1%) and extrasystoles originating from the right ventricular outflow tract (2.7%). Three patients developed complications during ablation (1.4%). Among congenital heart diseases, which occurred in 51 (15.4%) patients, atrial sept defect was the most frequent (27.4%), followed by ventricular sept defect (25.4%) and Ebstein's anomaly (17.6%). Conclusion: Electrophysiological study and radiofrequency ablation are effective tools for diagnosis and treatment of arrhythmias in the pediatric population. .

Fundamento: A ablação com radiofrequência é o tratamento não farmacológico de eleição para arritmias na população pediátrica. Porém, as arritmias e suas causas apresentam características particulares nesta população. Objetivos: Analisar as características epidemiológicas e os achados de estudo eletrofisiológico diagnóstico e ablação com radiofrequência na população pediátrica encaminhada à Eletrofisiologia do Instituto de Cardiologia do Rio Grande do Sul, a fim de caracterizar as suas particularidades. Resultados: Foram realizados 330 procedimentos (9,6% do total de procedimentos) em pacientes com idade inferior a 20 anos (14,33 ± 3,25 anos, variação entre 3 meses e 19 anos), dos quais 201 eram do sexo masculino (60,9%). Foram realizados 108 (32,7%) exames eletrofisiológicos diagnósticos e destes, 48,1% apresentaram anormalidades em seus achados. Ao todo, 219 ablações com radiofrequência foram realizadas (66,3%), obtendo-se sucesso em 84,8%. A presença de feixe acessório foi o achado mais prevalente, responsável por 158 casos (72,1%), seguida de taquicardia por reentrada nodal atrioventricular (16,8%), flutter atrial típico (3,1%) e extrassístole de via de saída de ventrículo direito (2,7%). Três pacientes apresentaram complicações durante a ablação (1,4%). Cardiopatia congênita esteve presente em 51 (15,4%) casos, sendo a comunicação interatrial a mais encontrada (27,4%), seguida de comunicação interventricular (25,4%) e anomalia de Ebstein (17,6%). Conclusão: Estudo eletrofisiológico e ablação com radiofrequência constituem ferramentas eficazes no diagnóstico e tratamento das arritmias na população pediátrica. .

Electrophysiological studies and radiofrequency ablations in children and adolescents with arrhythmia.

BACKGROUND: Radiofrequency ablation is the standard non-pharmacological treatment for arrhythmias in pediatric patients. However, arrhythmias and their associated causes have particular features in this population. OBJECTIVE: To analyze the epidemiological characteristics and findings of electrophysiological diagnostic studies and radiofrequency ablations in pediatric patients referred to the Electrophysiology Unit at Instituto de Cardiologia do Rio Grande do Sul, in order to characterize the particularities of this population. METHODS: Cross-sectional study with 330 electrophysiological procedures performed in patients aged less than 20 years between June 1997 and August 2013. RESULTS: In total, 330 procedures (9.6% of the overall procedures) were performed in patients aged less than 20 years (14.33 ± 3.25 years, age range 3 months to 19 years), 201 of which were males (60.9%). A total of 108 (32.7%) electrophysiological diagnostic studies were performed and of these, 48.1% showed abnormal findings. Overall, 219 radiofrequency ablations were performed (66.3%) with a success rate of 84.8%. The presence of an accessory pathway was the most prevalent finding, occurring in 158 cases (72.1%), followed by atrioventricular nodal reentrant tachycardia (16.8%), typical atrial flutter (3.1%) and extrasystoles originating from the right ventricular outflow tract (2.7%). Three patients developed complications during ablation (1.4%). Among congenital heart diseases, which occurred in 51 (15.4%) patients, atrial sept defect was the most frequent (27.4%), followed by ventricular sept defect (25.4%) and Ebstein's anomaly (17.6%). CONCLUSION: Electrophysiological study and radiofrequency ablation are effective tools for diagnosis and treatment of arrhythmias in the pediatric population.

Risco da radiação ionizante em mulheres férteis submetidas à ablação por radiofrequência / Risk of ionizing radiation in women of childbearing age undergoing radiofrequency ablation

FUNDAMENTO: A Comissão Internacional de Radiologia indica rastreamento com teste de gravidez a todas pacientes do gênero feminino em período fértil que serão submetidas a exame radiológico. Sabe-se que a radiação é teratogênica e que seu efeito é cumulativo. O potencial teratogênico inicia-se com doses próximas às das utilizadas durante esses procedimentos. Não se sabe a prevalência de teste de gravidez positivo em pacientes submetidos a estudo eletrofisiológico e/ou à ablação por cateter em nosso meio. OBJETIVO: Avaliar a prevalência de teste de gravidez positivo em pacientes do gênero feminino encaminhadas para estudo eletrofisiológico e/ou ablação por radiofrequência. MÉTODOS: Estudo transversal com análise de 2.966 pacientes submetidos a estudo eletrofisiológico e/ou ablação por cateter, de junho 1997 a fevereiro 2013, no Instituto de Cardiologia do Rio Grande do Sul. Foram realizados 1.490 exames em mulheres sendo que, destas, 769 encontravam-se em idade fértil. Todas as pacientes foram rastreadas com teste de gravidez no dia anterior ao procedimento. RESULTADOS: Detectou-se positividade do teste em três pacientes, impossibilitando a realização do exame. Observou-se prevalência de 3,9 casos por 1.000 mulheres em idade fértil. CONCLUSÃO: Devido ao baixo custo e à segurança, indica-se a realização de teste de rastreamento para gravidez a todas pacientes em idade fértil, uma vez que o grau de radiação ionizante necessária nesse procedimento é muito próximo ao limiar de teratogenicidade, principalmente no primeiro trimestre, quando os sinais de gestação não são exuberantes.

BACKGROUND: The International Commission of Radiology recommends a pregnancy screening test to all female patients of childbearing age who will undergo a radiological study. Radiation is known to be teratogenic and its effect is cumulative. The teratogenic potential starts at doses close to those used during these procedures. The prevalence of positive pregnancy tests in patients undergoing electrophysiological studies and/or catheter ablation in our midst is unknown. OBJECTIVE: To evaluate the prevalence of positive pregnancy tests in female patients referred for electrophysiological study and/or radiofrequency ablation. METHODS: Cross-sectional study analyzing 2966 patients undergoing electrophysiological study and/or catheter ablation, from June 1997 to February 2013, in the Institute of Cardiology of Rio Grande do Sul. A total of 1490 procedures were performed in women, of whom 769 were of childbearing age. All patients were screened with a pregnancy test on the day before the procedure. RESULTS: Three patients tested positive, and were therefore unable to undergo the procedure. The prevalence observed was 3.9 cases per 1000 women of childbearing age. CONCLUSION: Because of their safety and low cost, pregnancy screening tests are indicated for all women of childbearing age undergoing radiological studies, since the degree of ionizing radiation needed for these procedures is very close to the threshold for teratogenicity, especially in the first trimester, when the signs of pregnancy are not evident.

Risk of ionizing radiation in women of childbearing age undergoing radiofrequency ablation.

BACKGROUND: The International Commission of Radiology recommends a pregnancy screening test to all female patients of childbearing age who will undergo a radiological study. Radiation is known to be teratogenic and its effect is cumulative. The teratogenic potential starts at doses close to those used during these procedures. The prevalence of positive pregnancy tests in patients undergoing electrophysiological studies and/or catheter ablation in our midst is unknown. OBJECTIVE: To evaluate the prevalence of positive pregnancy tests in female patients referred for electrophysiological study and/or radiofrequency ablation. METHODS: Cross-sectional study analyzing 2966 patients undergoing electrophysiological study and/or catheter ablation, from June 1997 to February 2013, in the Institute of Cardiology of Rio Grande do Sul. A total of 1490 procedures were performed in women, of whom 769 were of childbearing age. All patients were screened with a pregnancy test on the day before the procedure. RESULTS: Three patients tested positive, and were therefore unable to undergo the procedure. The prevalence observed was 3.9 cases per 1000 women of childbearing age. CONCLUSION: Because of their safety and low cost, pregnancy screening tests are indicated for all women of childbearing age undergoing radiological studies, since the degree of ionizing radiation needed for these procedures is very close to the threshold for teratogenicity, especially in the first trimester, when the signs of pregnancy are not evident.

Glioblastoma multicêntrico originado em dois locais incomuns: cerebelo e tálamo / Multicentric glioblastoma arising in two unusual sites: cerebellum and thalamus

Multicentric glioblastomas (MGBM) arising in infra/supratentorial regions are uncommon lesions. The authors report a case of MGBM in a 61 year-old female patient, who presented a sudden onset of left hemiplegia. The magnetic resonance imaging (MRI) showed two expansive large lesions affecting cerebellum and thalamus, with strong contrast enhancement. The patient underwent resection of the cerebellar lesion. Microscopy revealed a high grade glial neoplasm exhibiting high mitotic index, areas of necrosis and microvascular proliferation. The neoplastic cells showed positive immunoexpression for glial fibrillary acidic protein (GFAP). The morphological findings were consistent with glioblastoma (GBM). The patient was referred to radiotherapy, with discrete signs of tumor regression after a 60-day clinical follow-up.

Glioblastomas multicêntricos (GBMM) originados em regiões infra/supratentoriais são lesões incomuns. Os autores relatam um caso de GBMM em paciente do sexo feminino, 61 anos de idade, que apresenta quadro súbito de hemiplegia esquerda. O exame de ressonância magnética (RM) mostrou duas lesões expansivas volumosas, com forte impregnação pelo contraste no cerebelo e no tálamo. A paciente foi submetida à ressecção da lesão cerebelar. À microscopia, foi identificada uma neoplasia glial de alto grau exibindo alto índice mitótico, áreas de necrose e proliferação microvascular. As células neoplásicas revelaram imunoexpressão positiva para proteína glial acídica (GFAP). O conjunto das alterações morfológicas foi consistente com glioblastoma. A paciente foi encaminhada para radioterapia, com sinais discretos de regressão tumoral após acompanhamento clínico de 60 dias.

Assessment of methyl methacrylate vapor toxicity on the rat tracheal epithelium.

Methyl methacrylate (MMA) is a monomer that is polymerized into resin by light and heat, producing a clear, resistant, durable and relatively inert plastic material. Because of these characteristics, MMA is largely used in Medicine as bone cement and in Dentistry, in dental braces and prostheses, thus generating continuous interest in its toxicity. Experimental and clinical studies have documented that monomers may cause a wide range of adverse health effects. The most important occupational exposure route of MMA is by inhalation. This study aims to evaluate the toxicity of MMA to the tracheal epithelium, according to the time of exposure. For this purpose, two experimental groups of rats were exposed to MMA by inhalation under poor ventilation: one group (n = 36) was exposed permanently, and the other (n = 36) was exposed during 8 hours per day, without water and food supply during the exposure period. A control group (n = 8) received normal air supply. Twelve animals of each study group were sacrificed after 5, 8 and 10 days of exposure together with two or four control animals. Twenty-nine (80.5%) of the rats continuously exposed to MMA developed inflammation on the tracheal epithelium, as well as 58.33% (n = 21) of those exposed 8 h/day and 87.5% (n = 7) of the control rats. No association was observed between the inflammatory process and MMA exposure; no significant alterations in the tracheal epithelium thickness were observed. Further studies on longer exposure times and analysis of other parameters will have to be conducted to exclude the possibility of tracheal damage by vapors of MMA.

Assessment of methyl methacrylate vapor toxicity on the rat tracheal epithelium / Análise da toxicidade dos vapores de metil metacrilato sobre o epitélio traqueal de ratos

O metil metacrilato (MMA) é um monômero que se polimeriza em resina pela ação da luz e do calor, transformando-se em plástico claro, resistente e durável, relativamente inerte. Por apresentar tais características, o MMA tem sido muito usado na Medicina, como cimento ósseo, e na Odontologia, em aparelhos e próteses dentais, o que tem suscitado interesse na avaliação de sua toxicidade. Estudos experimentais e clínicos têm mostrado que os monômeros podem causar uma gama de efeitos adversos. A principal via de exposição ocupacional ao MMA é a inalatória. Este trabalho visa a avaliar a ação tóxica do MMA sobre o epitélio traqueal em relação ao tempo de exposição. Para isso, dois grupos experimentais de ratos foram expostos ao MMA por inalação, com restrição de ventilação: um grupo (n = 36) foi exposto continuamente, e outro (n = 36) foi exposto durante oito horas diárias, sem água e comida durante o período de exposição. Um grupo controle (n = 8) recebeu ar normal. Doze animais de cada grupo de estudo foram sacrificados com 5, 8 e 10 dias de exposição, junto com dois ou quatro animais do grupo controle. Vinte e nove (80,5%) dos ratos expostos continuamente ao MMA apresentaram inflamação do epitélio traqueal, assim como 58,33% (n = 21) daqueles expostos 8 horas/dia e 87,5% (n = 7) dos controles. Não se observou associação entre o processo inflamatório e a exposição ao MMA, nem alterações significativas na medida da espessura do epitélio traqueal. Novos estudos, com tempo mais prolongado de exposição e análise de outros parâmetros, devem ser realizados para que seja excluída, totalmente, a possibilidade de dano traqueal por vapores de MMA.

Serovariedades de Salmonella em águas superficiais em San Luís, Argentina / Salmonella serotypes from surface waters in San Luis, Argentina

Resumo: Foi investigada a presença de Smonella em amostras de água colhidas pela técnica de Moore, em rios e açudes, durante um ano. Realizau-se um pré-enriquecimento em água peptomada tamponada e um enriquecimento em caldo tetrationato-verde brilhante com caldo Rappaport. Isolou-se em 0gar verde brilhantre com desoxicolato de sódio a 0,25 (por cento) e em ágar sulfito de bismuto. As colônias suspeitas foram estrudadas mediante provas bioqu1micas clássicas e sorológicas. Recuperou-se Salmonella em 6,66 (por cento) das amostras. Isolou-se S. panama, S. newport, S. sandiego e Salmonella sub-espécie IV, 40: Z4, Z23: esta última serovariedade constitui o primeiro isolamento na Argentina. Determinou-se o antibiograma pelo método de Kirby-Bauer. As 15 cepas isoladas foram sensíveis a trimetroprima-sulfametoxazol, gentamicina, tetraciclina, cloranfenicol, kamamicina e ácido nalidíxico, quanto à carbenicilina, 6 cepas foram resistentes, 7 mostraram sensibilidade intermediária e só 2 foram sensíveis. -Foram determinados perfis plasmídicos pela técnica de Birnboin e dOLY. Os pesos moleculares (PM) dos plasmídeos em megadaltons (MDa) foram determinados por comparaçäo com plasmídeos de PM conhecidos. Foram detectados plasmídeos de PM 40 MDa em S. newpot e de PM 17 MDa em S. sandiego. Seria de interesse a determinaçäo sistemática de marcadores epidemiológicos em surtos e casos esporádicos de salmonelose com o fim de estabelecer sua distribuiçäo geográfica na zona estudada da província de San Luis, assim como também a necessidade de uma vigilância microbiológica das águas superficiais e a implementaçäo de tratamentos de depuraçäo de águas cloacais adequadois antes de serem despejadas nos cursos de água (au)