Oswaldo Cruz Foundation

About: Oswaldo Cruz Foundation is a facility organization based out in Rio de Janeiro, Brazil. It is known for research contribution in the topics: Population & Trypanosoma cruzi. The organization has 18673 authors who have published 36752 publications receiving 802378 citations. The organization is also known as: Fundação Oswaldo Cruz & FIOCRUZ.

Macrophage-dependent IL-1β production induces cardiac arrhythmias in diabetic mice

Abstract: Diabetes mellitus (DM) encompasses a multitude of secondary disorders, including heart disease. One of the most frequent and potentially life threatening disorders of DM-induced heart disease is ventricular tachycardia (VT). Here we show that toll-like receptor 2 (TLR2) and NLRP3 inflammasome activation in cardiac macrophages mediate the production of IL-1β in DM mice. IL-1β causes prolongation of the action potential duration, induces a decrease in potassium current and an increase in calcium sparks in cardiomyocytes, which are changes that underlie arrhythmia propensity. IL-1β-induced spontaneous contractile events are associated with CaMKII oxidation and phosphorylation. We further show that DM-induced arrhythmias can be successfully treated by inhibiting the IL-1β axis with either IL-1 receptor antagonist or by inhibiting the NLRP3 inflammasome. Our results establish IL-1β as an inflammatory connection between metabolic dysfunction and arrhythmias in DM.

Effectiveness of the CoronaVac vaccine in older adults during a gamma variant associated epidemic of covid-19 in Brazil: test negative case-control study.

Abstract: Objective To estimate the effectiveness of the inactivated whole virus vaccine, CoronaVac (Sinovac Biotech), against symptomatic covid-19 in the elderly population of Sao Paulo state, Brazil during widespread circulation of the gamma variant. Design Test negative case-control study. Setting Community testing for covid-19 in Sao Paulo state, Brazil. Participants 43 774 adults aged ≥70 years who were residents of Sao Paulo state and underwent reverse transcription polymerase chain reaction (RT-PCR) testing for SARS-CoV-2 from 17 January to 29 April 2021. 26 433 cases with symptomatic covid-19 and 17 622 test negative controls with covid-19 symptoms were formed into 13 283 matched sets, one case with to up to five controls, according to age, sex, self-reported race, municipality of residence, previous covid-19 status, and date of RT-PCR test (±3 days). Intervention Vaccination with a two dose regimen of CoronaVac. Main outcome measures RT-PCR confirmed symptomatic covid-19 and associated hospital admissions and deaths. Results Adjusted vaccine effectiveness against symptomatic covid-19 was 24.7% (95% confidence interval 14.7% to 33.4%) at 0-13 days and 46.8% (38.7% to 53.8%) at ≥14 days after the second dose. Adjusted vaccine effectiveness against hospital admissions was 55.5% (46.5% to 62.9%) and against deaths was 61.2% (48.9% to 70.5%) at ≥14 days after the second dose. Vaccine effectiveness ≥14 days after the second dose was highest for the youngest age group (70-74 years)—59.0% (43.7% to 70.2%) against symptomatic disease, 77.6% (62.5% to 86.7%) against hospital admissions, and 83.9% (59.2% to 93.7%) against deaths—and declined with increasing age. Conclusions Vaccination with CoronaVac was associated with a reduction in symptomatic covid-19, hospital admissions, and deaths in adults aged ≥70 years in a setting with extensive transmission of the gamma variant. Vaccine protection was, however, low until completion of the two dose regimen, and vaccine effectiveness was observe to decline with increasing age among this elderly population.

Possible primary ecological niche of Cryptococcus neoformans.

Abstract: To study hollows of living trees as natural habitats of Cryptococcus neoformans in an endemic area of cryptococcosis in the northeastern region of Brazil, samples of decaying wood were collected inside 32 hollows of living trees and plated on niger seed agar. Identification of C. neoformans was based upon morphological and physiological tests. Canavanine-glycine-bromothymol medium was used to screen the varieties and Crypto Check Iatron Kit to serotype the isolates. A total of 123 C. neoformans colonies were recovered from samples of six (18.5%) out of 32 hollow trees. C. neoformans var. neoformans and C. neoformans var. gattii were found occurring alone (pink shower tree, fig tree and pottery tree) or sharing the same hollow (pink shower tree). Long lasting positivity (19-36 months) and significant number of cfu of C. neoformans per gram of decaying wood (0.15-21.7 x 10(3) cfu g(-1)) inside hollows of pink shower tree, fig tree and pottery tree were observed, indicating colonization of these habitats by the fungus. For the first time, C. n. var. neoformans and C. n. var. gattii were found sharing the same natural biotope, thus establishing a possible link between them in their life cycle in nature and suggesting the primary natural niche for the species.

Co-distribution and co-infection of chikungunya and dengue viruses

Abstract: Chikungunya and dengue infections are spatio-temporally related. The current review aims to determine the geographic limits of chikungunya, dengue and the principal mosquito vectors for both viruses and to synthesise current epidemiological understanding of their co-distribution. Three biomedical databases (PubMed, Scopus and Web of Science) were searched from their inception until May 2015 for studies that reported concurrent detection of chikungunya and dengue viruses in the same patient. Additionally, data from WHO, CDC and Healthmap alerts were extracted to create up-to-date global distribution maps for both dengue and chikungunya. Evidence for chikungunya-dengue co-infection has been found in Angola, Gabon, India, Madagascar, Malaysia, Myanmar, Nigeria, Saint Martin, Singapore, Sri Lanka, Tanzania, Thailand and Yemen; these constitute only 13 out of the 98 countries/territories where both chikungunya and dengue epidemic/endemic transmission have been reported. Understanding the true extent of chikungunya-dengue co-infection is hampered by current diagnosis largely based on their similar symptoms. Heightened awareness of chikungunya among the public and public health practitioners in the advent of the ongoing outbreak in the Americas can be expected to improve diagnostic rigour. Maps generated from the newly compiled lists of the geographic distribution of both pathogens and vectors represent the current geographical limits of chikungunya and dengue, as well as the countries/territories at risk of future incursion by both viruses. These describe regions of co-endemicity in which lab-based diagnosis of suspected cases is of higher priority.