Optimizing the procedure for mercury recovery from dental amalgam

Mercury, as any other heavy metal, may cause environmental damages due to its accumulation and biotransformation. Dental offices, whether private or institutional, use dental amalgam as a restorative material on a daily basis. Dental amalgam is composed of mercury (50%), silver (30%) and other metals. Approximately 30% of the amalgam prepared in dental offices (0.6 g per capsule) are wasted and inadequately discarded without any treatment. Methods for mercury recovery have been proposed previously, using high temperatures through exposure to direct flame (650°C), long processing time, and hazardous reagents as potassium cyanide. The purpose of this study was to develop a method to replace the direct flame by an electrical mantle in the process of mercury recovery. Results showed an average mercury recovery of 90% from 2 kg of amalgam after 30 minutes of processing time, thus optimizing the procedure. The proposed modifications allowed a significant reduction in processing time and a mercury recovery with high purity. The modified process also provided minimization of operator exposure to physical, chemical and ergonomic hazards, representing a technological advance compared to the risks inherent to the original method. It also provided environmental health and economy of energy resources by replacing a finite energy source (fossil and organic) by a more environmentally appropriate electric source, resulting in significant improvement of the procedure for mercury recovery from dental amalgam

A successful strategy for the recovering of active P21, an insoluble recombinant protein of Trypanosoma cruzi

Structural studies of proteins normally require large quantities of pure material that can only be obtained through heterologous expression systems and recombinant technique. in these procedures, large amounts of expressed protein are often found in the insoluble fraction, making protein purification from the soluble fraction inefficient, laborious, and costly. Usually, protein refolding is avoided due to a lack of experimental assays that can validate correct folding and that can compare the conformational population to that of the soluble fraction. Herein, we propose a validation method using simple and rapid 1D H-1 nuclear magnetic resonance (NMR) spectra that can efficiently compare protein samples, including individual information of the environment of each proton in the structure.Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)INBEQMeDIUniv Fed Uberlandia, Inst Ciencias Biomed, BR-38400 Uberlandia, MG, BrazilUniv São Paulo, Inst Fis Sao Carlos, Sao Carlos, SP, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, Vila Mariana, SP, BrazilUniv Fed Minas Gerais, Inst Ciencias Biol, Dept Biol Geral, Belo Horizonte, MG, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, Vila Mariana, SP, BrazilFAPESP: 2010/51867-6FAPESP: 2012/21153-7FAPEMIG: APQ-00621-11FAPEMIG: APQ-00305-12CAPES: 23038.005295/2011-40Web of Scienc

Mechanistic Insights into the Anti-angiogenic Activity of Trypanosoma cruzi Protein 21 and its Potential Impact on the Onset of Chagasic Cardiomyopathy

Chronic chagasic cardiomyopathy (CCC) is arguably the most important form of the Chagas Disease, caused by the intracellular protozoan Trypanosoma cruziit is estimated that 10-30% of chronic patients develop this clinical manifestation. The most common and severe form of CCC can be related to ventricular abnormalities, such as heart failure, arrhythmias, heart blocks, thromboembolic events and sudden death. Therefore, in this study, we proposed to evaluate the anti-angiogenic activity of a recombinant protein from T. cruzi named P21 (rP21) and the potential impact of the native protein on CCC. Our data suggest that the anti-angiogenic activity of rP21 depends on the protein's direct interaction with the CXCR4 receptor. This capacity is likely related to the modulation of the expression of actin and angiogenesis-associated genes. Thus, our results indicate that T. cruzi P21 is an attractive target for the development of innovative therapeutic agents against CCC.Univ Fed Sao Paulo, Escola Paulista Med, Departamento Microbiol Imunol Parasitol, BR-05508 Sao Paulo, SP, BrazilUniv Fed Uberlandia, Inst Ciencias Biomed, Dept Imunol, Lab Tripanosomatideos, Uberlandia, MG, BrazilUniv Fed Uberlandia, Inst Genet & Bioquim, Lab Bioquim & Toxinas Animais, Uberlandia, MG, BrazilCeTICS, Inst Butantan, Sao Paulo, BrazilUniv Fed Uberlandia, Fac Med, Centro Referencia Nacl Dermatol Sanitaria Hanseni, Lab Patol Mol & Biotecnol, Uberlandia, MG, BrazilUniv Fed Uberlandia, Inst Ciencias Biomed, Dept Immunol, Lab Osteoimunol & Imunol Tumores, Uberlandia, MG, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Departamento Microbiol Imunol Parasitol, BR-05508 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Departamento Microbiol Imunol Parasitol, BR-05508 Sao Paulo, SP, BrazilWeb of Scienc

Envelhecimento populacional: Desafios e estratégias na integração da geriatria com a saúde coletiva

Introduction: The phenomenon of population aging has emerged as a striking feature of contemporary societies, representing a significant shift in the age structure of populations worldwide. The increase in life expectancy and the decrease in birth rates are determining factors in this scenario, contributing to a progressive rise in the proportion of elderly individuals compared to other age groups. Methodology: To identify existing literature, specific MESH descriptors were chosen, encompassing key areas of research, including "Geriatrics," "Public Health," "Aging," and "Obesity." These terms were selected due to their relevance in analyzing challenges and strategies related to population aging. Results: Accessibility to quality healthcare services, suitable housing conditions, and financial resources are determining elements for the well-being of this population. Therefore, intervention strategies should address not only clinical issues but also the social and economic dimensions influencing the health of the elderly. Conclusion: Attention to the specific needs of geriatrics is crucial to ensure that the growing elderly population receives healthcare tailored to their unique characteristics. Recognizing clinical conditions, addressing obesity in the elderly, promoting mental health, and considering socio-economic disparities are critical elements for effective and compassionate practice in geriatrics.Introdução: O fenômeno do envelhecimento populacional tem se manifestado como uma marcante característica das sociedades contemporâneas, representando uma mudança significativa na estrutura etária das populações ao redor do mundo. O aumento da expectativa de vida e a diminuição das taxas de natalidade são fatores determinantes desse cenário, contribuindo para um aumento progressivo da proporção de idosos em relação aos demais grupos etários. Metodologia: Para identificar a literatura existente, foram escolhidos descritores MESH específicos que abrangem as áreas-chave da pesquisa, incluindo "Geriatrics", "Public Health", "Aging" e "Obesity". Esses termos foram selecionados devido à sua pertinência na análise dos desafios e estratégias relacionados ao envelhecimento populacional. Resultado: . A acessibilidade a serviços de saúde de qualidade, condições de moradia adequadas e recursos financeiros são elementos determinantes para o bem-estar dessa população. Portanto, estratégias de intervenção devem abordar não apenas as questões clínicas, mas também as dimensões sociais e econômicas que influenciam a saúde dos idosos. Conclusão: A atenção às necessidades específicas da geriatria é fundamental para garantir que a crescente população idosa receba cuidados de saúde adequados e adaptados às suas particularidades. O reconhecimento das condições clínicas, a abordagem da obesidade na terceira idade, a promoção da saúde mental e a consideração das disparidades socioeconômicas são elementos cruciais para uma prática eficaz e compassiva na geriatria

B-cell infection by Trypanosoma cruzi results in activation of Caspase-7, proteolytic cleavage of PLC1 and cell death

B lymphocytes contribute to immunity in several ways, like presentation of antigen to T cells, secretion of cytokines and the unique producer immunoglobulin cell. Publications have considered B lymphocytes important for the resistance to intracellular pathogens. Trypanosoma cruzi, an intracellular parasite and etiological agent of Chagas’ disease, sabotages humoral response by depletion of B lymphocytes, resulting in increased parasitemia and susceptibility to disease. However, the role of B lymphocytes in the pathogenesis of Chagas’ disease has been overshadowed by the emphasis on T cells research. This investigation demonstrated that T. cruzi can effectively infect B lymphocytes inducing actin polymerization at the site of parasite invasion followed by a general actin depolymerization. Phospholipase C inhibition potentiates the parasitism of B lymphocytes. Moreover, T. cruzi infection induces proteolytic cleavage of Phospholipase C-gamma1 and Caspase-7 activation in B lymphocytes. Notably, B lymphocytes do not support parasite infection and undergo to cell death.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorTese (Doutorado)As células B contribuem para imunidade de diversas maneiras, tais como: apresentação de antígenos aos linfócitos T, produção de citocinas, secreção de imunoglobulinas envolvidas na opsonização, fagocitose ou lise celular de patógenos por meio do sistema complemento. Ainda, as células B são responsáveis por componentes essenciais da resistência contra patógenos intracelulares. Trypanosoma cruzi é um parasita intracelular, causador da doença de Chagas, que consegue evadir da resposta humoral do hospedeiro induzindo a diminuição da quantidade de células B, principalmente aquelas especializadas no combate ao parasita. Dessa forma, ocorre uma elevada parasitemia, o indivíduo torna-se suscetível à doença e o parasita se estabelece cronicamente no hospedeiro. Apesar do protagonismo das células B no sistema imunológico, sua relevância na patogenia da doença de Chagas é ofuscada pela ênfase que se tem dado às pesquisas com células T nesse contexto. Este estudo mostra claramente que T. cruzi infecta células B, evento ainda não demonstrado por estudos prévios. O parasita interage com o citoesqueleto de actina dessas células causando polimerização no sítio de entrada, seguida por despolimerização geral. Ainda, a inibição farmacológica da Fosfolipase C intensificou a invasão do parasita que, por sua vez, ativa a Caspase-7 e a clivagem proteolítica da Fosfolipase C1, resultando em morte das células B por não suportarem o parasitismo

Estudos das vias de sinalização mobilizadas pela cepa G de Trypanosoma cruzi na invasão celular, da sinalização intracelular ativada pela proteína P21-HIS6 e seu renovelamento

Trypanosoma cruzi is the etiologic agent of Chagas disease, which induces a pathological hypertrophy in the heart, esophagus and colon. This disease affects millions of peoples in Latin America. Recently our group characterized a 21 kDa T. cruzi recombinant protein (P21-His6) based on native form secreted by T. cruzi. P21-His6 is purified from insoluble inclusion bodies or soluble fraction from bacterial extract. The protein obtained from each protocol has identical secondary structure and was capable of inducing parasite phagocytosis and increased zymosan particles internalization by macrophages cell being that process PI3 kinase signaling pathway dependent. In addition the refolding protocol generates of high amounts of the recombinant protein. Also we investigated the signaling pathway involved in amastigotes and trypomastigotes (living, dead and opsonized) T. cruzi developmental stages invasion using macrophages treated or not with signaling pathway inhibitors drugs. Opsonized parasites are internalized a lot. Living amastigotes triggered PI3K and MAPK signaling pathways, dead amastigotes activated only MAPKs pathway. Living and dead trypomastigotes activated all the signaling pathways studied.Mestre em Biologia Celular e Estrutural AplicadasTrypanosoma cruzi é o causador da Doença de Chagas, a qual induz alterações patológicas severas no coração, esôfago e cólon, afetando milhões de pessoas na América Latina. Recentemente nosso grupo caracterizou uma proteína recombinante de 21 kDa (P21-His6) baseada na forma nativa secretada por T. cruzi. Essa proteína aumentou a internalização de parasitas na célula hospedeira e estimulou o processo fagocítico de partículas de zymosan por macrófagos peritoneais. A proteína recombinante é purificada a partir dos corpos de inclusão e também a partir da fração solúvel do extrato bacteriano. As proteínas obtidas a partir de cada fração foram comparadas para verificar se o processo de renovelamento produzia uma proteína com a mesma estrutura secundária da proteína solúvel. Confirmou-se que independente do protocolo de purificação a estrutura secundária da proteína é a mesma, sendo que a proteína obtida a partir de cada fração é capaz de aumentar a internalização de parasitas e estimular o processo fagocítico de forma dependente da via de sinalização da PI3K. Os corpos de inclusão do extrato bacteriano fornece uma quantidade maior de proteína. Também investigamos as vias de sinalização envolvidas na invasão de macrófagos peritoneais, tratados com drogas inibidoras, por formas amastigotas extracelulares e tripomastigotas de cultura de tecido da cepa G de T. cruzi nas situações em que os parasitas estavam vivos, mortos ou opsonizados. Parasitas opsonizados são intensamente internalizados nos macrófagos tratados com inibidores das vias de sinalização. Amastigotas extracelulares (AE) vivos ativam as vias de PI3K e MAPKs e são internalizados em maior quantidade que AE mortos, que ativam apenas as vias das MAPKs. Tripomastigotas de cultura de tecidos vivos e mortos ativaram todas as vias de sinalização aqui estudadas

Recent advances in nanoparticle carriers for coordination complexes

Coordination compounds are substances in which a central metal atom is bonded to nonmetal atoms, or groups of atoms, called ligands. Examples include vitamin B-12, hemoglobin, chlorophyll, dyes and pigments, as well as catalysts used in organic synthesis. Coordination compounds have received much attention in recent years. This interest was prompted by the discovery that several coordination compounds exhibit activity against bacteria, fungi and cancer. Some coordination compounds are not in clinical use, because of poor water solubility. Because they are unable to cross the lipid membranes of cells, bioavailability and efficacy are low. Some researchers have applied nanotechnology to coordination compounds, hoping to reduce the number of doses required and the severity of side effects, and also to improve biological activity. Nanotechnology can deliver active components in sufficient concentrations throughout treatment, guiding it to the desired location of action; conventional treatments do not meet these requirements. In this study we review some drug delivery systems based on nanotechnology, such as microemulsions (MEs), cyclodextrin (CD), polymeric nanoparticles (PN), solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), magnetic and gold nanoparticles (MNPs / AuNPs) and liquid crystalline systems (LC), and coordination compounds.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Galectin-3: A Friend but Not a Foe during Trypanosoma cruzi Experimental Infection

Trypanosoma cruzi interacts with host cells, including cardiomyocytes, and induces the production of cytokines, chemokines, metalloproteinases, and glycan-binding proteins. Among the glycan-binding proteins is Galectin-3 (Gal-3), which is upregulated after T. cruzi infection. Gal-3 is a member of the lectin family with affinity for β-galactose containing molecules; it can be found in both the nucleus and the cytoplasm and can be either membrane-associated or secreted. This lectin is involved in several immunoregulatory and parasite infection process. Here, we explored the consequences of Gal-3 deficiency during acute and chronic T. cruzi experimental infection. Our results demonstrated that lack of Gal-3 enhanced in vitro replication of intracellular parasites, increased in vivo systemic parasitaemia, and reduced leukocyte recruitment. Moreover, we observed decreased secretion of pro-inflammatory cytokines in spleen and heart of infected Gal-3 knockout mice. Lack of Gal-3 also led to elevated mast cell recruitment and fibrosis of heart tissue. In conclusion, galectin-3 expression plays a pivotal role in controlling T. cruzi infection, preventing heart damage and fibrosis

Lavori atipici ed economia digitale - Prospettiva luso-italo-brasiliana. Contratos atípicos de emprego e economia digital - Perspectiva luso-ítalo-brasileira

Il seminario “Lavori atipici ed economia digitale - Prospettiva luso-italo-brasiliana”, svolto il 28 aprile 2022, presso l'Università La Sapienza di Roma, ha avuto come obiettivo riunire studenti, ricercatori e docenti per confrontarsi su temi legati ai profondi cambiamenti subiti dal mercato del lavoro, presso un momento in cui l'economia globale non riesce a generare sufficienti posti di lavoro. Tra i cambiamenti analizzati durante il seminario si può citare, tra gli altri, la crescita di forme di occupazione diverse dai modelli tradizionalmente utilizzati. Si osserva che le cosiddette “forme atipici di lavoro” possono servire a finalità specifiche, come situazioni di lavoro stagionale, ma possono anche essere utilizzate per regolare nuove attività e forme di occupazione, derivanti dall'evoluzione della società nel nostro tempo. Quest’opera contiene studi relativi al lavoro su piattaforma digitale, contratti a tempo determinato, lavoro temporaneo, somministrazione, telelavoro o smart working, lavoro intermittente, lavoro part-time, tra le altre forme di contratti atipici. In questo modo gli organizzatori, l’università Sapienza di Roma, l’Università Lusófona e l’Instituto Iberoamericano de Estudos Juridícos – IBEROJUR, invitano la comunità accademica, formata da giuristi e non giuristi, giovani ricercatori e professori, a leggere questo libro, che presenta riflessioni critiche degli autori sulle sfide del mondo del lavoro, in una prospettiva globalizzata

Geoeconomic variations in epidemiology, ventilation management, and outcomes in invasively ventilated intensive care unit patients without acute respiratory distress syndrome: a pooled analysis of four observational studies

Background: Geoeconomic variations in epidemiology, the practice of ventilation, and outcome in invasively ventilated intensive care unit (ICU) patients without acute respiratory distress syndrome (ARDS) remain unexplored. In this analysis we aim to address these gaps using individual patient data of four large observational studies. Methods: In this pooled analysis we harmonised individual patient data from the ERICC, LUNG SAFE, PRoVENT, and PRoVENT-iMiC prospective observational studies, which were conducted from June, 2011, to December, 2018, in 534 ICUs in 54 countries. We used the 2016 World Bank classification to define two geoeconomic regions: middle-income countries (MICs) and high-income countries (HICs). ARDS was defined according to the Berlin criteria. Descriptive statistics were used to compare patients in MICs versus HICs. The primary outcome was the use of low tidal volume ventilation (LTVV) for the first 3 days of mechanical ventilation. Secondary outcomes were key ventilation parameters (tidal volume size, positive end-expiratory pressure, fraction of inspired oxygen, peak pressure, plateau pressure, driving pressure, and respiratory rate), patient characteristics, the risk for and actual development of acute respiratory distress syndrome after the first day of ventilation, duration of ventilation, ICU length of stay, and ICU mortality. Findings: Of the 7608 patients included in the original studies, this analysis included 3852 patients without ARDS, of whom 2345 were from MICs and 1507 were from HICs. Patients in MICs were younger, shorter and with a slightly lower body-mass index, more often had diabetes and active cancer, but less often chronic obstructive pulmonary disease and heart failure than patients from HICs. Sequential organ failure assessment scores were similar in MICs and HICs. Use of LTVV in MICs and HICs was comparable (42·4% vs 44·2%; absolute difference -1·69 [-9·58 to 6·11] p=0·67; data available in 3174 [82%] of 3852 patients). The median applied positive end expiratory pressure was lower in MICs than in HICs (5 [IQR 5-8] vs 6 [5-8] cm H2O; p=0·0011). ICU mortality was higher in MICs than in HICs (30·5% vs 19·9%; p=0·0004; adjusted effect 16·41% [95% CI 9·52-23·52]; p<0·0001) and was inversely associated with gross domestic product (adjusted odds ratio for a US$10 000 increase per capita 0·80 [95% CI 0·75-0·86]; p<0·0001). Interpretation: Despite similar disease severity and ventilation management, ICU mortality in patients without ARDS is higher in MICs than in HICs, with a strong association with country-level economic status