Sustainable intensification using irrigation and N fertilization for pasture production in Tocantins, Brazil.

To verify the influence of irrigation in a pasture of Panicum maximum cv. Massai was carried out a field research testing rainfed and two irrigation depths (SO and 100% of evapotranspiration) and 300 kg ha-1 year-1 of N-urea, during one year at the periods Jun-Sep, Oct-Nov, Dec-Mar and Apr-May, in Tocantins state, Brazil

Sustainable intensification using irrigation and N fertilization for pasture production in Tocantins, Brazil.

Cattle raising is among the main Brazilian economic activities. Currently, there are 169 million hectares covered by tropical grasslands and 30% of this area is degraded. In the last 40 years, the area occupied by grasslands in Brazil increased only 17% while the meat production increased 114% and that fact was only possible due to national effort and investments on agricultural research, development and innovation. To verify the influence of irrigation in a pasture of Panicum maximum cv. Massai was carried out a field research testing rainfed and two irrigation depths (SO and 100% of evapotranspiration) and 300 kg ha-1 year-1 of N-urea, during one year at the periods Jun-Sep, Oct-Nov, Dec-Mar and Apr-May, in Tocantins state, Brazil. The parameters are one animal unit (AU) corresponding to 450 kg of liveweight, a daily dry matter intake of 11.25 kg. The accumulated dry matter (kg ha-1 day-1 ) obtained by the 100% depth was significantly higher than the others in almost all periods analyzed, and during Jun-Sep the treatment 50% depth showed no significant difference when compared to 100% depth suggesting seasonality probably related to low temperatures. The results revealed the potential to achieve a stocking rate of 6.44, 4.20 and 3.51 AU ha-1 year-1 with 100%, 50% depths and rainfed treatment, respectively. Despite promising results, further studies on physiology, phenology and economy must be done to confirm the feasibility of using irrigation for pasture production in Tocantins

Phenotyping the virulence of SARS-CoV-2 variants in hamsters by digital pathology and machine learning

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has continued to evolve throughout the coronavirus disease-19 (COVID-19) pandemic, giving rise to multiple variants of concern (VOCs) with different biological properties. As the pandemic progresses, it will be essential to test in near real time the potential of any new emerging variant to cause severe disease. BA.1 (Omicron) was shown to be attenuated compared to the previous VOCs like Delta, but it is possible that newly emerging variants may regain a virulent phenotype. Hamsters have been proven to be an exceedingly good model for SARS-CoV-2 pathogenesis. Here, we aimed to develop robust quantitative pipelines to assess the virulence of SARS-CoV-2 variants in hamsters. We used various approaches including RNAseq, RNA in situ hybridization, immunohistochemistry, and digital pathology, including software assisted whole section imaging and downstream automatic analyses enhanced by machine learning, to develop methods to assess and quantify virus-induced pulmonary lesions in an unbiased manner. Initially, we used Delta and Omicron to develop our experimental pipelines. We then assessed the virulence of recent Omicron sub-lineages including BA.5, XBB, BQ.1.18, BA.2, BA.2.75 and EG.5.1. We show that in experimentally infected hamsters, accurate quantification of alveolar epithelial hyperplasia and macrophage infiltrates represent robust markers for assessing the extent of virus-induced pulmonary pathology, and hence virus virulence. In addition, using these pipelines, we could reveal how some Omicron sub-lineages (e.g., BA.2.75 and EG.5.1) have regained virulence compared to the original BA.1. Finally, to maximise the utility of the digital pathology pipelines reported in our study, we developed an online repository containing representative whole organ histopathology sections that can be visualised at variable magnifications (https://covid-atlas.cvr.gla.ac.uk). Overall, this pipeline can provide unbiased and invaluable data for rapidly assessing newly emerging variants and their potential to cause severe disease

Immune-Complex Mimics as a Molecular Platform for Adjuvant-Free Vaccine Delivery

Protein-based vaccine development faces the difficult challenge of finding robust yet non-toxic adjuvants suitable for humans. Here, using a molecular engineering approach, we have developed a molecular platform for generating self-adjuvanting immunogens that do not depend on exogenous adjuvants for induction of immune responses. These are based on the concept of Immune Complex Mimics (ICM), structures that are formed between an oligomeric antigen and a monoclonal antibody (mAb) to that antigen. In this way, the roles of antigens and antibodies within the structure of immune complexes are reversed, so that a single monoclonal antibody, rather than polyclonal sera or expensive mAb cocktails can be used. We tested this approach in the context of Mycobacterium tuberculosis (MTB) infection by linking the highly immunogenic and potentially protective Ag85B with the oligomeric Acr (alpha crystallin, HspX) antigen. When combined with an anti-Acr monoclonal antibody, the fusion protein formed ICM which bound to C1q component of the complement system and were readily taken up by antigen-presenting cells in vitro. ICM induced a strong Th1/Th2 mixed type antibody response, which was comparable to cholera toxin adjuvanted antigen, but only moderate levels of T cell proliferation and IFN-γ secretion. Unfortunately, the systemic administration of ICM did not confer statistically significant protection against intranasal MTB challenge, although a small BCG-boosting effect was observed. We conclude that ICM are capable of inducing strong humoral responses to incorporated antigens and may be a suitable vaccination approach for pathogens other than MTB, where antibody-based immunity may play a more protective role

Comorbidades e evolução clínica em pacientes críticos com COVID-19 atendidos em hospital regional do Planalto Norte Catarinense

Regarding the epidemiological scenario of coping with COVID-19, it is important to consider the importance and lack of regional epidemiological data in Santa Catarina (SC) – Brazil. Therefore, the present study aimed to study and discuss comorbidities, epidemiological data, and outcome in patients with COVID19 treated and hospitalized in the intensive care unit (ICU) of a regional hospital in the northern plateau of Santa Catarina (SC). Through retrospective investigative and descriptive analysis, using data indexed in medical records (from March to December 2020) of patients hospitalized in ICU-Covid19, we studied the clinical characteristics and intra-hospital evolutions. In this population, it was found that epidemiological indicators such as gender, risk factors and mortality agree with those described worldwide, which were: higher prevalence of males, without significant differences in relation to age in relation to females. However, there was a significant difference in relation to the mean age of the population that evolved to death in relation to the population that evolved to hospital discharge. Regional epidemiological studies support health, disease, and health market data indicators that are summarily important for the development of health strategies and planning. Thus, the present study aims to contribute to the knowledge of this scenario in the health region in question, as well as the global epidemiological scenario of this disease condition.Quanto ao cenário epidemiológico de enfrentamento da COVID-19, é importante considerar a importância e carência de dados epidemiológicos regionais de Santa Catarina (SC) – Brasil. Diante disso, o presente estudo teve como objetivo estudar e discutir comorbidades, dados epidemiológicos e desfecho em pacientes com COVID19 atendidos e internados em unidade de terapia intensiva (UTI) de um hospital regional de planalto norte catarinense (SC). Por meio de análise investigativa e descritiva, do tipo retrospectiva, utilizando-se de dados indexados em prontuários médicos (de março à dezembro de 2020) de pacientes internatos em UTI-Covid19, estudou-se sobre as características clínicas e evoluções intra hospitalar. Nessa população, verificou-se que indicadores epidemiológicos como sexo, fatores de risco e mortalidade estão de acordo com os mundialmente descritos, os quais foram: maior prevalência de indivíduos do sexo masculino, sem diferenças significativas em relação à faixa etária em relação ao sexo feminino. No entanto, houve diferença significativa em relação à média de idade da população que evoluiu para óbito em relação à população que evoluiu para alta hospitalar. Estudos epidemiológicos regionais apoiam indicadores de saúde, doença e dados do mercado de saúde que são sumariamente importantes para o desenvolvimento de estratégias e planejamento de saúde. Dessa forma, o presente estudo visa contribuir para o conhecimento desse cenário na região de saúde em questão, bem como do cenário epidemiológico mundial dessa condição de doença

New Insights into the Mechanisms of Embryonic Stem Cell Self-Renewal under Hypoxia: A Multifactorial Analysis Approach

Previous reports have shown that culturing mouse embryonic stem (mES) cells at different oxygen tensions originated different cell proliferation patterns and commitment stages depending on which signaling pathways are activated or inhibited to support the pluripotency state. Herein we provide new insights into the mechanisms by which oxygen is influencing mES cell self-renewal and pluripotency. A multifactorial approach was developed to rationally evaluate the singular and interactive control of MEK/ERK pathway, GSK-3 inhibition, and LIF/STAT3 signaling at physiological and non-physiological oxygen tensions. Collectively, our methodology revealed a significant role of GSK-3-mediated signaling towards maintenance of mES cell pluripotency at lower O2 tensions. Given the central role of this signaling pathway, future studies will need to focus on the downstream mechanisms involved in ES cell self-renewal under such conditions, and ultimately how these findings impact human models of pluripotency