Forest structure and function strongly depend on and concurrently influence environmental conditions.Tree performance is generally governed by its genetics and environment;thus,recent hotspots in this field include tr...Forest structure and function strongly depend on and concurrently influence environmental conditions.Tree performance is generally governed by its genetics and environment;thus,recent hotspots in this field include tree genotype×environment,phenotype×environment,and functional trait×environment interactions.The editorial,review,and 22 original research articles in this Special Issue,"Tree ecophysiology in the context of climate change",highlight ecophysiological phenomena(e.g.,climate hormesis,seed germination,tree mortality),processes(e.g.,tree metabolism,photosynthate allocation,nutrient uptake and transport),indicators(e.g.,carbon sequestration,pollutants),measurements(e.g.,thermal time methods,soil quality indices,vegetation spectral index,and near-infrared leaf reflectance),and modeling(e.g.,climate correlations with tree growth,photo synthetic phenology,hydraulic strategies,OliveCan model)in the context of global climate change.Understanding forest-environment interactions from an ecophysiological perspective as climate changes provides insights into species fitness in suboptimal environments,species competition for limited resources,and phylogenetic divergence or convergence of species,and predicting species distributions.展开更多
Fish gill is a multifunctional organ with role in acid-base balance, elimination of nitrogen waste and mainly gas exchange and ion regulation. There is a high energetic coast for ionregulation in freshwater fish maint...Fish gill is a multifunctional organ with role in acid-base balance, elimination of nitrogen waste and mainly gas exchange and ion regulation. There is a high energetic coast for ionregulation in freshwater fish maintained in salt water but a raise in growing taxes was observed for some species. The freshwater Nile tilapia, Oreochromis niloticus, is widely used in aquaculture farmers and the aim of this study was to investigate the changes on the gill filaments nltrastructure in fish kept under different salinities. Alevins were obtained and transported to laboratory of studies in animal stress Federal University of Paran~. Established groups in 0%0, 16%0 and 32%0 salt water with 12 animals in each one. After 30 days of exposition, the animals were anesthetized and the second gill arches were dissected and processed for scanning and transmission electron microscopy. The mitochondrial rich cells fractional area and density in the gill epithelia were determinated. The under scanning electron microscopy （SEM） in 0%0 salinity group reveal changes in the apical ridge of mitochondrial rich cells （MRCs）. In all other groups, the observations revealed numerous crypts disposed mainly in the filament epithelia. In transmission electron microscopy （TEM） two distinct types of MRCs were observed. The data of MRCFA and density revealed in 0%0 and 16%0 values significantly elevated in comparison to 32%0. Despite these lower values, the density in the gill epithelia was higher. The main differences found between the groups revealed that fish exposed to 16%o salinity have less MRCs aperture to the environment and are less related to ion regulation process.展开更多
Drainage system is a poorly investigated basic sanitation and urban planning issue in the Amazon, which is often related to flooding processes and public health. The aim of the present research is to correlate Prelimi...Drainage system is a poorly investigated basic sanitation and urban planning issue in the Amazon, which is often related to flooding processes and public health. The aim of the present research is to correlate Preliminary Risk of Flooding (PRF) to independent variables, based on the following methodology: 1) identifying and classifying risk areas by using the Geographic Information System (GIS) and 2) statistically correlating risk to sanitary and environmental variables. Results have shown that preliminary risk is correlated to, at least, seven sanitary and environmental variables, depending on flood influence area;and there are significant correlations observed in the rainy season interval [probability or significance (p) 0.05]. In conclusion, PRF is higher in the rainy season, but it is spatially influenced by the elevation of terrain, number of flooding points, drainage typology and Environmental Salubrity Index (ESI) of neighborhoods, which directly affect the water quality in nearby groundwater wells (Total Coliforms, nitrate (NO<sub>3</sub>) and ammonia (NH<sub>3</sub>)). However, this influence can eventually significantly change in the dry season.展开更多
Enzymes play a pivotal role in meat processing and maturation,starting with endogenous enzymes that catalyse a partial proteolysis in natural meat that enhances texture and flavor,to exogenous enzymes that may be inco...Enzymes play a pivotal role in meat processing and maturation,starting with endogenous enzymes that catalyse a partial proteolysis in natural meat that enhances texture and flavor,to exogenous enzymes that may be incorporated for additional processing.Therefore,a question is raised whether endogenous and exogenous proteases could be used to improve the quality of meat products originated from in vitro cell-based technology.This manuscript aims at presenting the main applications of enzymes in meat processing,starting with conventional meat products and expanding to reported and potential applications in cultured meat technologies.Enzymes are applied since the early stages of cell isolation,multiplication and detaching from supports.The use of endogenous enzymes,such as cathepsins and calpains,has been proposed to improve the palatability of cultivated meat,and the application of transglutaminases has already been reported in scientific papers and patent documents,with the aim of promoting crosslinking reactions among proteins.This feature can be used to modulate the texture of cultivated meat products.Also,their use has been directed to the manufacture of scaffolds and microcarriers for animal cell cultivation.As concluded from the scientific and technological literature survey,it is evident that a substantial area of study remains unexplored regarding the utilization of enzymes in cultivated meat products.展开更多
Food waste and by-products are generated throughout the food processing and storage chain.In a world facing climate collapse and limited space for expanding cultivable land needed to feed a growing global population,u...Food waste and by-products are generated throughout the food processing and storage chain.In a world facing climate collapse and limited space for expanding cultivable land needed to feed a growing global population,utilizing food from sustainable production chains has become a significant challenge.Additionally,there is a worldwide trend towards consuming natural and healthy foods that are as free from chemical compounds as possible during production,processing,and preparation.Gradually,eating habits have adapted to these new trends,and new foods are being introduced into diets.In this context,research into sustainable practices has emerged worldwide,promoting the increased consumption of plant-based foods.The central idea of this article is connected to global concerns regarding food sources,minimizing waste,and innovatively using every ingredient.Fermentation,a traditional and natural food preservation technique,can be a vital tool for enhancing flavours and textures while increasing nutritional value through the action of specific enzymes.This article aims to highlight the main challenges of using food processing by-products in human nutrition and explore possible strategies to improve their quality through the enzymatic action of microorganisms.展开更多
Cardiac rehabilitation protocols applied during the inhospital phase(phaseⅠ)are subjective and their results are contested when evaluated considering what should be the three basic principles of exercise prescription...Cardiac rehabilitation protocols applied during the inhospital phase(phaseⅠ)are subjective and their results are contested when evaluated considering what should be the three basic principles of exercise prescription:specificity,overload and reversibility.In this review,we focus on the problems associated with the models of exercise prescription applied at this early stage in-hospital and adopted today,especially the lack of clinical studies demonstrating its effectiveness.Moreover,we present the concept of"periodization"as a useful tool in the search for better results.展开更多
In neuroscience research,neuronal models are crucial tools for elucidating the molecular and cellular processes involved in the disorders of the nervous system.Facilitating easily and reproducibly executable studies,i...In neuroscience research,neuronal models are crucial tools for elucidating the molecular and cellular processes involved in the disorders of the nervous system.Facilitating easily and reproducibly executable studies,in vitro models,such as the SH-SY5Y cell line culture,help us explore the pathophysiological mechanisms of neurodegenerative diseases;they are also essential for the efficient screening of drugs for treating the diseases of the nervous system(Peng et al.,2021;Strother et al.,2021).展开更多
Background:The Hepadnaviridae family is composed of small hepatotropic DNA viruses,divided into two main genera:Avihepadnavirus,which infects birds;and Orthohepadnavirus,which infects mammals.The human hepatitis B vir...Background:The Hepadnaviridae family is composed of small hepatotropic DNA viruses,divided into two main genera:Avihepadnavirus,which infects birds;and Orthohepadnavirus,which infects mammals.The human hepatitis B virus(HBV)is a member of the latter family and contains a relaxed circular double-stranded DNA genome of approximately 3 kb,and the objective of this study is to evaluate the genetic diversity of the genome of the Hepadnaviridae family.Materials and Methods:For this study,we evaluated the 26 NCBI reference sequences of the Hepadnaviridae family.Result:The two main genera,Avihepadnavirus and Orthohepadnavirus,show low similarity between them.The Orthohepadnavirus,to which HBV belongs,has two important hosts,monkeys and bats,while the genus,which infects humans,has greater diversity but is similar to the viruses that infect monkeys.The Paraepadnavirus isolated from the white sucker fish and the Herpetohepadnavirus from the Tibetan frog showed strong similarity with the Avihepadnavirus found in birds.The Metahepadnavirus isolated from the bluegill fish was the Hepadnaviridae which had the greatest difference,with less than 20%similarity using CLC Sequence Viewer.Conclusion:The Hepadnaviridae genomic replication cycle involves a late reverse transcriptase(RT)step.This polymerase,however,does not have proofreading activity,resulting in genetic variability in the Hepadnaviridae family.展开更多
Interleukin-6 （IL-6） is a pleiotropic, pro-inflammatory cytokine produced by various types of cells, including macrophages. Within the IL-6 gene promoter region, the signature binding motif of CBFI/Su（H）/Lag-1 （...Interleukin-6 （IL-6） is a pleiotropic, pro-inflammatory cytokine produced by various types of cells, including macrophages. Within the IL-6 gene promoter region, the signature binding motif of CBFI/Su（H）/Lag-1 （CSL）, a key DNA-binding protein in the Notch signaling pathway, was identified and found to overlap with a consensus nuclear factor （NF）-κB-binding site. Notch signaling is highly conserved and is involved in the regulation of biological functions in immune cells. In this study, we investigated the role of Notch signaling in the regulation of the IL-6transcript in murine macrophages. The upregulation of Notch1 protein levels and the appearance of cleaved Notch1 （Va11744） correlated well with the increased IL-6 mRNA expression levels in murine primary bone marrow-derived macrophages （BMMφ） after activation by lipopolysaccharide （LPS） together with interferon-gamma （IFN-γ）. Treatment of BMMφ with the γ-secretase inhibitor IL-CHO to suppress the transduction of Notch signaling resulted in a partial decrease in the level of IL-6mRNA and the amount of I L-6 protein produced. In contrast, the overexpression of a constitutively activated intracellular Notch I protein （N^IC） in the RAW264.7 macrophage-like cell line resulted in significantly higher IL-6transcript expression levels than in cells transfected with the empty vector control. The NF-κB inhibitor completely abrogated IL-6 mRNA expression induced by the overexpression of N^IC. Chromatin immunoprecipitation （CHIP） using an anti-Notch1 antibody demonstrated that Notch 1 is associated with the IL-6promoter in RAW264.7 cells activated by LPS/IFN-γ but not in unstimulated cells. Taken together, these results strongly suggest that Notch 1 positively regulates IL-6 expression via NF-κB in activated macrophages.展开更多
Macrophages are cellular targets for infection by bacteria and viruses. The fate of infected macrophages plays a key role in determining the outcome of the host immune response. Apoptotic cell death of macrophages is ...Macrophages are cellular targets for infection by bacteria and viruses. The fate of infected macrophages plays a key role in determining the outcome of the host immune response. Apoptotic cell death of macrophages is considered to be a protective host defense that eliminates pathogens and infected cells. In this study, we investigated the involvement of Notch signaling in regulating apoptosis in macrophages treated with tuberculin purified protein derivative （PPD）. Murine bone marrow-derived macrophages （BMMs） treated with PPD or infected with Mycobacterium bovis Bacillus Calmette-Guerin （BCG） induced upregulation of Notch1. This upregulation correlated well with the upregulation of the anti-apoptotic gene mcl-1 both at the transcriptional and translational levels. Decreased levels of Notch I and Mcl- 1 were observed in BMM treated with PPD when a gamma secretase inhibitor （GSI）, which inhibits the processing of Notch receptors, was used. Moreover, silencing Notch1 in the macrophage-like cell line RAW264.7 decreased Mcl-1 protein expression, suggesting that Notch1 is critical for Mcl-1 expression in macrophages. A significant increase in apoptotic cells was observed upon treatment of BMM with PPD in the presence of GSI compared to the vehicle-control treated cells. Finally, analysis of the mcl-1 promoter in humans and mice revealed a conserved potential CSURBP-Jκ binding site. The association of Notch I with the mcl-1 promoter was confirmed by chromatin immunoprecipitation. Taken together, these results indicate that Notch I inhibits apoptosis of macrophages stimulated with PPD by directly controlling the mcl-1 promoter.展开更多
Cheese whey proteins are natural vehicles for biological agents that are used as an inexpensive and effective coating material in the encapsulation of probiotics.In this work,the yeast Kluyveromyces marxianus,of probi...Cheese whey proteins are natural vehicles for biological agents that are used as an inexpensive and effective coating material in the encapsulation of probiotics.In this work,the yeast Kluyveromyces marxianus,of probiotic potential,was associated with the prebiotic Plantago ovata(Psyllium)in particles coated with cheese whey.The efficiency of encapsulation,gastrointestinal tract(GIT)viability,particle morphology,and adhesion to enteral cells were analyzed.K.marxianus was encapsulated in different formulations with alginate(alg),psyllium(psy),and cheese whey(cw)through an extrusion process associated with vibrational technology.Yeasts encapsulated in different wall materials[alginate-psyllium-cheese whey(alg-psy-cw),alginate(alg),alginate-psyllium(alg-psy),and alginate-cheese whey(alg-cw)]were adequately protected,resulting in high cell viability(11.32,9.77,9.13,10.95 log CFU.g1,respectively).Regarding the bioavailability assay after three months of storage under refrigeration(±4℃),cells encapsulated in wall material alg-psy-cw demonstrated the best viability(>6 log CFU.g^(-1)).Encapsulated yeasts showed greater resistance to acidic conditions when exposed to simulations of the gastrointestinal tract,demonstrating a lower diffusion rate in the formulation made with wall material alg-psy-cw(10.03 log CFU.g^(-1)).The adhesion rate to Caco-2 cells was high(±3,166 yeasts/100 Caco-2 cells).Finally,the developed product in this study was found to be suitable for incorporation in functional foods,as well as in pharmaceutical products,demonstrating its biotechnological potential.展开更多
Objective:To investigate the presence of antibodies against Toxoplasma gondii(T.gondii)in Mirounga leonina(M.leonina)Linnaeus from Elephant Island,Antarctica.Methods:The animals were anesthetized,restrained,measured,w...Objective:To investigate the presence of antibodies against Toxoplasma gondii(T.gondii)in Mirounga leonina(M.leonina)Linnaeus from Elephant Island,Antarctica.Methods:The animals were anesthetized,restrained,measured,weighed and had their blood collected by venipuncture of intervertebral lumbar epidural vein.Blood samples were collected from 102 individuals.Indirect hemagglutination and serum dilution at a proportion of 1:25 was used for specific immunoglobulin G anti-T.gondii detection.Results:Only one(0.98%)specimen,a newly weaned calf,was seropositive.Conclusions:This study is the highest serological survey for antibody detection against T.gondii in M.leonina.The results suggest a low level of exposure to T.gondii,probably due to the absence of felids in the study area.The seropositivity presented by the elephant seal may be related to the presence of oocysts in water or cysts in their preys.Despite being reported the presence of the parasite in fish and molluscs,there are no records of tissue cysts or oocysts in squid or fish of the diet of M.leonina.Thus,further parasitological studies focused on preys of elephant seals are needed for a better understanding of infection of M.leonina by T.gondii.展开更多
基金the Excellence Action Plan for China STM Journals(EAPCSTMJ-C-077)International Infl uence Promotion Project of China STM Journals(Journal of Forestry ResearchPIIJ2-B-18).
文摘Forest structure and function strongly depend on and concurrently influence environmental conditions.Tree performance is generally governed by its genetics and environment;thus,recent hotspots in this field include tree genotype×environment,phenotype×environment,and functional trait×environment interactions.The editorial,review,and 22 original research articles in this Special Issue,"Tree ecophysiology in the context of climate change",highlight ecophysiological phenomena(e.g.,climate hormesis,seed germination,tree mortality),processes(e.g.,tree metabolism,photosynthate allocation,nutrient uptake and transport),indicators(e.g.,carbon sequestration,pollutants),measurements(e.g.,thermal time methods,soil quality indices,vegetation spectral index,and near-infrared leaf reflectance),and modeling(e.g.,climate correlations with tree growth,photo synthetic phenology,hydraulic strategies,OliveCan model)in the context of global climate change.Understanding forest-environment interactions from an ecophysiological perspective as climate changes provides insights into species fitness in suboptimal environments,species competition for limited resources,and phylogenetic divergence or convergence of species,and predicting species distributions.
文摘Fish gill is a multifunctional organ with role in acid-base balance, elimination of nitrogen waste and mainly gas exchange and ion regulation. There is a high energetic coast for ionregulation in freshwater fish maintained in salt water but a raise in growing taxes was observed for some species. The freshwater Nile tilapia, Oreochromis niloticus, is widely used in aquaculture farmers and the aim of this study was to investigate the changes on the gill filaments nltrastructure in fish kept under different salinities. Alevins were obtained and transported to laboratory of studies in animal stress Federal University of Paran~. Established groups in 0%0, 16%0 and 32%0 salt water with 12 animals in each one. After 30 days of exposition, the animals were anesthetized and the second gill arches were dissected and processed for scanning and transmission electron microscopy. The mitochondrial rich cells fractional area and density in the gill epithelia were determinated. The under scanning electron microscopy （SEM） in 0%0 salinity group reveal changes in the apical ridge of mitochondrial rich cells （MRCs）. In all other groups, the observations revealed numerous crypts disposed mainly in the filament epithelia. In transmission electron microscopy （TEM） two distinct types of MRCs were observed. The data of MRCFA and density revealed in 0%0 and 16%0 values significantly elevated in comparison to 32%0. Despite these lower values, the density in the gill epithelia was higher. The main differences found between the groups revealed that fish exposed to 16%o salinity have less MRCs aperture to the environment and are less related to ion regulation process.
文摘Drainage system is a poorly investigated basic sanitation and urban planning issue in the Amazon, which is often related to flooding processes and public health. The aim of the present research is to correlate Preliminary Risk of Flooding (PRF) to independent variables, based on the following methodology: 1) identifying and classifying risk areas by using the Geographic Information System (GIS) and 2) statistically correlating risk to sanitary and environmental variables. Results have shown that preliminary risk is correlated to, at least, seven sanitary and environmental variables, depending on flood influence area;and there are significant correlations observed in the rainy season interval [probability or significance (p) 0.05]. In conclusion, PRF is higher in the rainy season, but it is spatially influenced by the elevation of terrain, number of flooding points, drainage typology and Environmental Salubrity Index (ESI) of neighborhoods, which directly affect the water quality in nearby groundwater wells (Total Coliforms, nitrate (NO<sub>3</sub>) and ammonia (NH<sub>3</sub>)). However, this influence can eventually significantly change in the dry season.
基金supported by the Araucária Foundation[NAPI Proteínas Alternativas,grant number 19.810.961-4]the National Council for Scientific and Technological Development-CNPq[grant number 309237/2021-1].
文摘Enzymes play a pivotal role in meat processing and maturation,starting with endogenous enzymes that catalyse a partial proteolysis in natural meat that enhances texture and flavor,to exogenous enzymes that may be incorporated for additional processing.Therefore,a question is raised whether endogenous and exogenous proteases could be used to improve the quality of meat products originated from in vitro cell-based technology.This manuscript aims at presenting the main applications of enzymes in meat processing,starting with conventional meat products and expanding to reported and potential applications in cultured meat technologies.Enzymes are applied since the early stages of cell isolation,multiplication and detaching from supports.The use of endogenous enzymes,such as cathepsins and calpains,has been proposed to improve the palatability of cultivated meat,and the application of transglutaminases has already been reported in scientific papers and patent documents,with the aim of promoting crosslinking reactions among proteins.This feature can be used to modulate the texture of cultivated meat products.Also,their use has been directed to the manufacture of scaffolds and microcarriers for animal cell cultivation.As concluded from the scientific and technological literature survey,it is evident that a substantial area of study remains unexplored regarding the utilization of enzymes in cultivated meat products.
文摘Food waste and by-products are generated throughout the food processing and storage chain.In a world facing climate collapse and limited space for expanding cultivable land needed to feed a growing global population,utilizing food from sustainable production chains has become a significant challenge.Additionally,there is a worldwide trend towards consuming natural and healthy foods that are as free from chemical compounds as possible during production,processing,and preparation.Gradually,eating habits have adapted to these new trends,and new foods are being introduced into diets.In this context,research into sustainable practices has emerged worldwide,promoting the increased consumption of plant-based foods.The central idea of this article is connected to global concerns regarding food sources,minimizing waste,and innovatively using every ingredient.Fermentation,a traditional and natural food preservation technique,can be a vital tool for enhancing flavours and textures while increasing nutritional value through the action of specific enzymes.This article aims to highlight the main challenges of using food processing by-products in human nutrition and explore possible strategies to improve their quality through the enzymatic action of microorganisms.
文摘Cardiac rehabilitation protocols applied during the inhospital phase(phaseⅠ)are subjective and their results are contested when evaluated considering what should be the three basic principles of exercise prescription:specificity,overload and reversibility.In this review,we focus on the problems associated with the models of exercise prescription applied at this early stage in-hospital and adopted today,especially the lack of clinical studies demonstrating its effectiveness.Moreover,we present the concept of"periodization"as a useful tool in the search for better results.
基金supported in part by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior(Capes-Brazil),No.001(to MIG).
文摘In neuroscience research,neuronal models are crucial tools for elucidating the molecular and cellular processes involved in the disorders of the nervous system.Facilitating easily and reproducibly executable studies,in vitro models,such as the SH-SY5Y cell line culture,help us explore the pathophysiological mechanisms of neurodegenerative diseases;they are also essential for the efficient screening of drugs for treating the diseases of the nervous system(Peng et al.,2021;Strother et al.,2021).
文摘Background:The Hepadnaviridae family is composed of small hepatotropic DNA viruses,divided into two main genera:Avihepadnavirus,which infects birds;and Orthohepadnavirus,which infects mammals.The human hepatitis B virus(HBV)is a member of the latter family and contains a relaxed circular double-stranded DNA genome of approximately 3 kb,and the objective of this study is to evaluate the genetic diversity of the genome of the Hepadnaviridae family.Materials and Methods:For this study,we evaluated the 26 NCBI reference sequences of the Hepadnaviridae family.Result:The two main genera,Avihepadnavirus and Orthohepadnavirus,show low similarity between them.The Orthohepadnavirus,to which HBV belongs,has two important hosts,monkeys and bats,while the genus,which infects humans,has greater diversity but is similar to the viruses that infect monkeys.The Paraepadnavirus isolated from the white sucker fish and the Herpetohepadnavirus from the Tibetan frog showed strong similarity with the Avihepadnavirus found in birds.The Metahepadnavirus isolated from the bluegill fish was the Hepadnaviridae which had the greatest difference,with less than 20%similarity using CLC Sequence Viewer.Conclusion:The Hepadnaviridae genomic replication cycle involves a late reverse transcriptase(RT)step.This polymerase,however,does not have proofreading activity,resulting in genetic variability in the Hepadnaviridae family.
文摘Interleukin-6 （IL-6） is a pleiotropic, pro-inflammatory cytokine produced by various types of cells, including macrophages. Within the IL-6 gene promoter region, the signature binding motif of CBFI/Su（H）/Lag-1 （CSL）, a key DNA-binding protein in the Notch signaling pathway, was identified and found to overlap with a consensus nuclear factor （NF）-κB-binding site. Notch signaling is highly conserved and is involved in the regulation of biological functions in immune cells. In this study, we investigated the role of Notch signaling in the regulation of the IL-6transcript in murine macrophages. The upregulation of Notch1 protein levels and the appearance of cleaved Notch1 （Va11744） correlated well with the increased IL-6 mRNA expression levels in murine primary bone marrow-derived macrophages （BMMφ） after activation by lipopolysaccharide （LPS） together with interferon-gamma （IFN-γ）. Treatment of BMMφ with the γ-secretase inhibitor IL-CHO to suppress the transduction of Notch signaling resulted in a partial decrease in the level of IL-6mRNA and the amount of I L-6 protein produced. In contrast, the overexpression of a constitutively activated intracellular Notch I protein （N^IC） in the RAW264.7 macrophage-like cell line resulted in significantly higher IL-6transcript expression levels than in cells transfected with the empty vector control. The NF-κB inhibitor completely abrogated IL-6 mRNA expression induced by the overexpression of N^IC. Chromatin immunoprecipitation （CHIP） using an anti-Notch1 antibody demonstrated that Notch 1 is associated with the IL-6promoter in RAW264.7 cells activated by LPS/IFN-γ but not in unstimulated cells. Taken together, these results strongly suggest that Notch 1 positively regulates IL-6 expression via NF-κB in activated macrophages.
文摘Macrophages are cellular targets for infection by bacteria and viruses. The fate of infected macrophages plays a key role in determining the outcome of the host immune response. Apoptotic cell death of macrophages is considered to be a protective host defense that eliminates pathogens and infected cells. In this study, we investigated the involvement of Notch signaling in regulating apoptosis in macrophages treated with tuberculin purified protein derivative （PPD）. Murine bone marrow-derived macrophages （BMMs） treated with PPD or infected with Mycobacterium bovis Bacillus Calmette-Guerin （BCG） induced upregulation of Notch1. This upregulation correlated well with the upregulation of the anti-apoptotic gene mcl-1 both at the transcriptional and translational levels. Decreased levels of Notch I and Mcl- 1 were observed in BMM treated with PPD when a gamma secretase inhibitor （GSI）, which inhibits the processing of Notch receptors, was used. Moreover, silencing Notch1 in the macrophage-like cell line RAW264.7 decreased Mcl-1 protein expression, suggesting that Notch1 is critical for Mcl-1 expression in macrophages. A significant increase in apoptotic cells was observed upon treatment of BMM with PPD in the presence of GSI compared to the vehicle-control treated cells. Finally, analysis of the mcl-1 promoter in humans and mice revealed a conserved potential CSURBP-Jκ binding site. The association of Notch I with the mcl-1 promoter was confirmed by chromatin immunoprecipitation. Taken together, these results indicate that Notch I inhibits apoptosis of macrophages stimulated with PPD by directly controlling the mcl-1 promoter.
基金This work was supported by the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico(CNPq)(grant no.308515/2020-0)University of Vale do Taquari-Univates.
文摘Cheese whey proteins are natural vehicles for biological agents that are used as an inexpensive and effective coating material in the encapsulation of probiotics.In this work,the yeast Kluyveromyces marxianus,of probiotic potential,was associated with the prebiotic Plantago ovata(Psyllium)in particles coated with cheese whey.The efficiency of encapsulation,gastrointestinal tract(GIT)viability,particle morphology,and adhesion to enteral cells were analyzed.K.marxianus was encapsulated in different formulations with alginate(alg),psyllium(psy),and cheese whey(cw)through an extrusion process associated with vibrational technology.Yeasts encapsulated in different wall materials[alginate-psyllium-cheese whey(alg-psy-cw),alginate(alg),alginate-psyllium(alg-psy),and alginate-cheese whey(alg-cw)]were adequately protected,resulting in high cell viability(11.32,9.77,9.13,10.95 log CFU.g1,respectively).Regarding the bioavailability assay after three months of storage under refrigeration(±4℃),cells encapsulated in wall material alg-psy-cw demonstrated the best viability(>6 log CFU.g^(-1)).Encapsulated yeasts showed greater resistance to acidic conditions when exposed to simulations of the gastrointestinal tract,demonstrating a lower diffusion rate in the formulation made with wall material alg-psy-cw(10.03 log CFU.g^(-1)).The adhesion rate to Caco-2 cells was high(±3,166 yeasts/100 Caco-2 cells).Finally,the developed product in this study was found to be suitable for incorporation in functional foods,as well as in pharmaceutical products,demonstrating its biotechnological potential.
基金Supported by Brazilian National Council of Technological and Scientific Development(CNPq)(Institutional process number 67.0018/98-8).
文摘Objective:To investigate the presence of antibodies against Toxoplasma gondii(T.gondii)in Mirounga leonina(M.leonina)Linnaeus from Elephant Island,Antarctica.Methods:The animals were anesthetized,restrained,measured,weighed and had their blood collected by venipuncture of intervertebral lumbar epidural vein.Blood samples were collected from 102 individuals.Indirect hemagglutination and serum dilution at a proportion of 1:25 was used for specific immunoglobulin G anti-T.gondii detection.Results:Only one(0.98%)specimen,a newly weaned calf,was seropositive.Conclusions:This study is the highest serological survey for antibody detection against T.gondii in M.leonina.The results suggest a low level of exposure to T.gondii,probably due to the absence of felids in the study area.The seropositivity presented by the elephant seal may be related to the presence of oocysts in water or cysts in their preys.Despite being reported the presence of the parasite in fish and molluscs,there are no records of tissue cysts or oocysts in squid or fish of the diet of M.leonina.Thus,further parasitological studies focused on preys of elephant seals are needed for a better understanding of infection of M.leonina by T.gondii.
