Effectiveness of a UVC air disinfection system for the HVAC of an ICU.

Ultraviolet germicidal irradiation (UVGI) uses short-wave ultraviolet (UVC) light to inactivate organisms like viruses, bacteria, and fungi. UVC inactivates a wide range of microorganisms by damaging the structure of nucleic acids and proteins at the molecular level, so they become unable to replicate and cause disease. Thus, UVC can improve indoor air quality by controlling bioaerosols and can be used as an engineering device to interrupt the transmission of pathogenic organisms and potential bioterrorism agents. Recently, the World Health Organization recognized that the COVID-19 virus could be transmitted across large distances, suggesting that indoor ventilation is key in airborne transmission. As a test for the future dissemination of UVC light installations to improve indoor air quality in Hospitals in Sergipe State, Brazil, we made a first installation of UVGI disinfection lamps, strategically placed in the Heating, Ventilating, and Air Conditioning (HVAC) system of the Intensive Care Unit (ICU) at the University Hospital of Lagarto, Federal University of Sergipe, Brazil. Six 15 W low-vapor-pressure mercury lamps emitting 253.7 nm UVGI were installed in the ducts of the fan coil, maximizing their luminous interaction in the air passage. One of the greatest advantages of this type of installation is that the lamps were completely covered, avoiding any risk of hazardous exposure to people and animals. Microbiological tests were carried out to verify the germicidal effect, analyzing the viability of microorganisms circulating in the environment. In this paper, we present our encouraging results, demonstrating the effectiveness of the installation, suggesting that similar devices should be installed in HVAC systems to avoid biological risk to people inside buildings. In addition, we believe that this study may provide useful evidence and guidance for the design of equipment intended to abate the microorganisms that may be used in CBRNE terror attacks.

Increased expression of ALDH-1 is associated with clinical parameters of salivary glands neoplasms.

The enzyme aldehyde dehydrogenase-1 (ALDH-1) is a known putative tumour stem cells (TSC) marker, and these cells are implicated in carcinogenesis and progression of human neoplasms. We aimed to evaluate ALDH-1 expression in benign and malignant salivary gland neoplasms and its clinicopathological and prognostic significance. Expression of ALDH-1 was investigated by immunohistochemistry and confirmed by Western Blot analysis in 154 salivary gland neoplasms (103 malignant and 51 benign neoplasms). The expression was identified in the parenchyma of malignant (n = 88; 85.6%) and benign (100%) neoplasms. Overall, expression in the parenchyma varied considerably and was not associated with clinical parameters in most malignant neoplasms, however, a high expression in mucoepidermoid carcinomas (MEC) was associated with advanced pathological TNM stage (p = 0.047). The presence of ALDH-1 in stromal cells of malignant neoplasms (n = 67; 65.0%) was associated with lymph node metastasis (p = 0.032), tumour recurrence (p = 0.006) and death (p = 0.013). Overall and disease-free survival in 5 and 10 years was lower in patients with diagnosis of adenoid cystic carcinoma, tumour recurrence, advanced staging, and presence of ALDH-1 in the stroma. When adjusted by multivariate analysis, advanced staging and stromal expression were independent prognostic factors affecting disease-free survival. Our findings provide evidence that cells characterized as TSC in the parenchyma and stroma are differentially present among the different types of neoplasms studied and may be related to tumourigenesis, biological behaviour and persistence capacity of malignant tumours of the salivary gland.

Tricho-dento-osseous syndrome: a brief review for dentistry / Síndrome trico-dento-óssea: uma breve revisão para odontologia

Introduction: Tricho-dento-osseous syndrome is a ultra-rare ectodermal dysplasia related to genetic alterations in the DLX3 gene of interest to the health sciences due to its clinical manifestations. Aim: To synthesize the scientific evidence about tricho-dento-osseous syndrome, especially for den-tistry. Methods: A bibliographic search was performed in the MEDLINE / PubMed, Web of Science and Scopus databases. A search strategy with descriptors was applied to all databases mentioned to reach scientific articles. The articles reached in all databases had their titles and abstracts read in search of adaptation to the proposed objective. There was no restriction on the year of publication, country or language. Literature review: Patients diagnosed with this syndrome have dental enamel defects and severe taurodontism, especially in the permanently lower first molars. In addition to these signs, other manifestations may be associated, such as curly hair, increased bone density and changes in craniofacial bones. The diagnosis of tricho-dento-osseous syndrome can be challenging due to the heterogeneity and wide phenotypic variation presented by patients with DLX3 mutations, since this gene is associated with several functions, especially related to cell differentiation and biomineralization. In addi-tion, it is necessary to consider that other dental anomalies may be confused with tricho-dento-osseous syndrome, especially cases of imperfect amelogenesis associated with taurodontism. Conclusion: For dentistry, oral manifestations caused by this syndrome become relevant for diagnostic and therapeutic purposes, although there are no clinical protocols for dental management of this patients.

Introdução: A síndrome trico-dento-óssea é uma displasia ectodérmica ultra-rara relacionada a alterações genéticas no gene DLX3de interesse para as ciências da saúde de-vido à suas manifestações clínicas. Objetivo: Sintetizar as evidências científicas sobre a síndrome trico-dento-óssea, especialmente para odontologia. Materiais e métodos: Uma pesquisa bibliográfica foi realizada nas bases de dados ME-DLINE/PubMed, Web of Science e Scopus. Uma estratégia de busca com descritores foi aplicada em todas as bases de dados mencionadas para alcançar os artigos científicos. Os artigos alcançados em todas as bases de dados tiveram seus títulos e resumos lidos em busca da adequação ao objetivo proposto. Não houve restrição quanto ao ano de publicação, país ou idioma. Revisão de literatura: Os pacientes diagnos-ticados com essa síndrome apresentam defeitos no esmalte dentário e taurodontismo severo, principalmente nos pri-meiros molares permanentemente inferiores. Além desses sinais, outras manifestações podem estar associadas, como cabelos crespos, aumento da densidade óssea e alterações nos ossos craniofaciais. O diagnóstico da síndrome trico-dento-óssea pode ser desafiador devido à heterogeneidade e ampla variação fenotípica apresentada pelos pacientes com mutações em DLX3, uma vez que esse gene está associado a várias funções, principalmente relacionadas à diferenciação e biomineralização celular. Além disso, é necessário considerar que outras anomalias dentárias podem ser confundidas com a síndrome trico-dento-óssea, principalmente nos casos de amelogênese imperfeita associada ao taurodontismo. Con-clusão: Para a odontologia, as manifestações orais causadas por essa síndrome tornam-se relevantes para fins diagnós-ticos e terapêuticos, embora não existam protocolos clínicos para o tratamento odontológico específico destes pacientes.