Antiviral action of aqueous extracts of propolis from Scaptotrigona aff. postica (Hymenoptera; Apidae) against Zica, Chikungunya, and Mayaro virus.

The limited availability of antivirals for new highly pathogenic strains of virus has become a serious public health. Therefore, news products against these pathogens has become an urgent necessity. Among the multiple sources for news antibiotics and antivirals, insect exudates or their products has become an increasingly frequent option. Insects emerged 350 million years ago and have showed a high adaptability and resistance to the most varied biomes. Their survival for so long, in such different environments, is an indication that they have a very efficient protection against environmental infections, despite not having a developed immune system like mammals. Since the ancient civilizations, the products obtained from the bee have been of great pharmacological importance, being used as antimicrobial, anti-inflammatory, antitumor and several other functions. Investigations of biological activity of propolis have been carried out, mainly in the species Apis mellifera, and its product have showed activity against some important viruses. However, for the Meliponini species, known as stingless bees, there are few studies, either on their chemical composition or on their biological activities. The importance of studying these bees is because they come from regions with native forests, and therefore with many species of plants not yet studied, in addition to which they are regions still free of pesticides, which guarantees a greater fidelity of the obtained data. Previous studies by our group with crude hydroalcoholic extract of propolis demonstrated an intense antiviral activity against Herpes, influenza, and rubella viruses. In this work, we chose to use aqueous extracts, which eliminates the presence of other compounds besides those originally present in propolis, in addition to extracting substances different from those obtained in alcoholic extracts. Therefore, this study aimed to identify, isolate and characterize compounds with antiviral effects from aqueous propolis extracts from Scaptotrigona aff postica, in emerging viruses such as zicavirus, chikungunya, and mayaro virus. The evaluation of the antiviral activity of the crude and purified material was performed by reducing infectious foci in VERO cell cultures. The results obtained with crude propolis, indicate a high reduction of zica virus (64×) and mayaro (128×) when was used 10% v/v of propolis. The reduction of chikungunya virus was of 256 fold, even when was used 5% v/v of propolis. The chemical characterization of the compounds present in the extracts was performed by high-pressure liquid chromatography. Through the purification of propolis by HPLC and mass spectrometry, it was possible to identify and isolate a peak with antiviral activity. This substance showed activity against all viruses tested. When purified fraction was used, the reduction observed was of 16 fold for zicavirus, 32 fold for mayaro virus and 512 fold for chikungunya virus. Likewise, it was observed that the antiviral response was concentration dependent, being more intense when propolis was added 2 h after the viral infection. Now we are carrying out the chemical characterization of the purified compounds that showed antiviral action.

Phagocytotic activity and gene expression of leukocytes isolated from Astyanax lacustris.

The constant intensification of aquaculture has considerable increased the stress levels of farmed fish and, consequently, the number and intensity of diseases outbreaks. Thus, studies on fish immune response, especially regarding the interaction of fish leukocytes with potential pathogens and xenobiotics are of great importance in order to develop new prophylactic and curative strategies. We isolated leukocytes from the head kidney of Astyanax lacustris-an important Neotropical fish species for aquaculture and a potential model for Neotropical aquaculture research-using a Percoll centrifugation protocol. The isolated leukocytes were incubated with lipopolysaccharide (LPS), and the expression of genes IL-1ß, IL-8, LysC, and LysG were measured. We assessed the phagocytotic activity of leukocytes using Congo red-dyed yeast, a novel and cost-effective protocol that has been developed in this study. The isolated leukocytes responded to LPS induction, exhibiting strong IL-1ß and IL-8 upregulation, two of the most important pro-inflammatory interleukins for vertebrates immune reponse. The optimal concentration of yeast for the phagocytic assay was 106 cells mL-1, resulting in acceptable phagocytic capacity (PC) but without excess of yeasts during the counting process, ensuring a high precision and accuracy of the method. To the best of our knowledge, the present study is the first to investigate the in vitro gene expression and phagocytic activity of leukocytes isolated from A. lacustris. Our findings will serve as a reference for future studies on the immunology and toxicology of Neotropical fish.

Precision technologies for predictive diagnosis and study of the allometric growth of broiler chickens with breast myopathies.

1. An experiment was carried out to validate techniques as predictive diagnostic tools for breast myopathies and to study the allometric growth of distinct parts of the body and meat quality of broilers.2. Infrared thermography was performed at 35 d of age. The surface temperatures of breasts of 300 birds were recorded, followed by ultrasound imaging.3. The birds were slaughtered and the cuts were made to weigh the body parts. Then, the breasts were evaluated as for the presence and severity of myopathies, from which nine treatments were established represented by the associated degrees of the myopathies white striping and wooden breast and breasts classified as normal.4. There was no difference in surface temperatures and echogenicity values between normal breasts and breasts affected by myopathies. At 35 d of age few fillets classified as normal were found.5. The breast showed late growth in relation to the body, regardless of characteristic lesions of myopathies. The most severe score of wooden breast affected meat quality variables.

Phagocytotic activity and gene expression of leukocytes isolated from Astyanax lacustris / Atividade fagocítica e expressão gênica de leucócitos isolados de Astyanax lacustris

The constant intensification of aquaculture has considerable increased the stress levels of farmed fish and, consequently, the number and intensity of diseases outbreaks. Thus, studies on fish immune response, especially regarding the interaction of fish leukocytes with potential pathogens and xenobiotics are of great importance in order to develop new prophylactic and curative strategies. We isolated leukocytes from the head kidney of Astyanax lacustris­an important Neotropical fish species for aquaculture and a potential model for Neotropical aquaculture research­using a Percoll centrifugation protocol. The isolated leukocytes were incubated with lipopolysaccharide (LPS), and the expression of genes IL-1ß, IL-8, LysC, and LysG were measured. We assessed the phagocytotic activity of leukocytes using Congo red-dyed yeast, a novel and cost-effective protocol that has been developed in this study. The isolated leukocytes responded to LPS induction, exhibiting strong IL-1ß and IL-8 upregulation, two of the most important pro-inflammatory interleukins for vertebrates immune reponse. The optimal concentration of yeast for the phagocytic assay was 106 cells mL-1, resulting in acceptable phagocytic capacity (PC) but without excess of yeasts during the counting process, ensuring a high precision and accuracy of the method. To the best of our knowledge, the present study is the first to investigate the in vitro gene expression and phagocytic activity of leukocytes isolated from A. lacustris. Our findings will serve as a reference for future studies on the immunology and toxicology of Neotropical fish.

A constante intensificação da aquicultura tem aumentado consideravelmente os níveis de estresse dos animais cultivados e, consequentemente, o número e a intensidade dos surtos de doenças. Logo, estudos sobre a resposta imune dos peixes, especialmente relacionados com a interação dos leucócitos de peixes com potenciais patógenos e xenobióticos, são de grande importância para o desenvolvimento de novas estratégias profiláticas e curativas. No presente trabalho, nós obtivemos sucesso ao isolar leucócitos oriundos do rim cranial de Astyanax lacustris ­ uma importante espécie de peixe Neotropical para a aquicultura e um modelo em potencial para pesquisas em aquicultura Neotropical ­ usando um protocolo de centrifugação com Percoll. Os leucócitos isolados foram incubados com lipossacarídeo (LPS) e, a expressão dos genes IL-1ß, IL-8, LysC, e LysG foi avaliada. Ainda, um novo protocolo para avaliação da atividade fagocítica dos leucócitos utilizando leveduras coradas com Vermelho Congo foi estabelecido. Os leucócitos isolados responderam à indução com LPS, exibindo up regulation dos genes IL-1ß e IL-8, duas das interleucinas pró-inflamatórias mais importantes para a resposta imune de vertebrados. Além do mais, a concentração ótima de leveduras para a avaliação da fagocitose foi de 106 células mL-1, resultando em uma capacidade fagocítica (PC) aceitável, mas sem excesso de leveduras durante o processo de contagem, garantindo maior precisão e eficácia do método. Até o presente momento, o presente estudo é o primeiro a investigar a expressão gênica e atividade fagocítica de leucócitos isolados de A. lacustris através da abordagem in vitro. Ainda, nossos resultados servirão de referência para futuros estudos em imunologia e toxicologia de peixes Neotropicais.

Diretriz Latino-americana sobre o Diagnóstico e Tratamento da Alergia Ocular ­ Em nome da Sociedade Latinoamericana de Alergia, Asma e Imunologia (SLAAI) / Latin American Guideline on the Diagnosis and Treatment of Ocular Allergy ­ On behalf of the Latin American Society of Allergy, Asthma and Immunology (SLAAI)

A alergia ocular, também conhecida como conjuntivite alérgica (CA), é uma reação de hipersensibilidade mediada por imunoglobulina E (IgE) do olho desencadeada por aeroalérgenos, principalmente ácaros da poeira doméstica e pólen de gramíneas. Os sintomas geralmente consistem em prurido ocular ou periocular, lacrimejamento e olhos vermelhos que podem estar presentes durante todo o ano ou sazonalmente. A alergia ocular tem frequência elevada, é subdiagnosticada e pode ser debilitante para o paciente. É potencialmente danosa para a visão, nos casos em que ocasiona cicatrização corneana grave, e na maioria dos pacientes associa-se a outros quadros alérgicos, principalmente rinite, asma e dermatite atópica. É classificada em conjuntivite alérgica perene, conjuntivite alérgica sazonal, ceratoconjuntivite atópica e ceratoconjuntivite vernal. O diagnóstico procura evidenciar o agente etiológico e a confirmação se dá pela realização do teste de provocação conjuntival. O tratamento baseia-se em evitar o contato com os desencadeantes, lubrificação, anti-histamínicos tópicos, estabilizadores de mastócitos, imunossupressores e imunoterapia específica com o objetivo de obter o controle e prevenir as complicações da doença.

Ocular allergy, also known as allergic conjunctivitis, is an immunoglobulin E-mediated hypersensitivity reaction of the eye triggered by airborne allergens, primarily house dust mites and grass pollen. Symptoms usually consist of ocular or periocular itching, watery eyes, and red eyes that may be present year-round or seasonally. Ocular allergy has a high frequency, is underdiagnosed, and can be debilitating for the patient. It is potentially harmful to vision in cases of severe corneal scarring, and in most patients, it is associated with other allergic conditions, especially rhinitis, asthma, and atopic dermatitis. It is classified as perennial allergic conjunctivitis, seasonal allergic conjunctivitis, atopic keratoconjunctivitis, and vernal keratoconjunctivitis. Diagnosis seeks to identify the etiologic agent, and confirmation is given by conjunctival provocation testing. Treatment is based on avoiding contact with triggers, lubrication, topical antihistamines, mast cell stabilizers, immunosuppressants, and specific immunotherapy with the aim of achieving control and preventing disease complications.

Stress during first gestation of ewes impairs memory and learning of male offspring.

This study aimed to investigate the influence of gestational stress induced by lipopolysaccharide (LPS, Escherichia coli) on the physiological changes of ewes, as well as on the subsequent behavioral interaction between ewes and lambs and on the memory and learning of 30-day-old offspring in a T-maze. Thirty-six nulliparous pregnant crossbred Santa Ines ewes with an initial live weight of 45 ± 6 kg, age of 12 ± 2 months, and body condition score between 3 and 3.5 (on a scale of 1 to 5) were divided into two treatments: LPS treatment (E. coli; 0.8 µg.kg-1) and Control (placebo/saline) administered in late pregnancy (day 120). Blood samples were collected before (0 h at 5:00 h) and 1 h, 2 h, 4 h, 8 h, 12 h, 24 h after the administration of LPS or placebo to determine the cortisol release curve. Rectal temperature was measured at the same time points. After birth, male lambs (N = 19) were used to evaluate the maternal-offspring behavioral interaction, weight, and cognitive ability in a T-maze. Blood cortisol and rectal temperature of ewes increased after LPS administration and returned to baseline levels after 24 h. The activities facilitating and stimulating suckling were higher on LPS group (P < 0.05). Lambs whose mothers were challenged with LPS during late pregnancy showed greater learning and memory disabilities including fear behavior and the inability to make decisions at 30 days of age in the T-maze. In sheep, the immunological stress induced by LPS in late pregnancy promotes an inflammatory response characterized by specific rectal temperature and cortisol release profiles, improving maternal care that can increase offspring survival; however, the exposure of sheep fetuses to maternal inflammation causes cognitive impairment in lambs at 30 days of age, which could not be reduced by the behavioral interaction between the mother and offspring.

Difference between the cell wall roughnesses of mothers and daughters of Saccharomyces cerevisiae subjected to high pressure stress.

High hydrostatic pressure (HHP) stress generates cellular responses similar to those to other stresses that yeasts endure in fermentation tanks. Structural and spatial compaction of molecules, as well as weakening and stretching of plasma membranes and cell walls, are often observed and have a significant influence on the fermentative process. Atomic force microscopy (AFM) yields accurate data on the morphological characteristics of yeast cell walls, providing important insights for the development of more productive yeast strains. Saccharomyces cerevisiae cell wall assessment using AFM in the intermittent contact reading mode using a silicon cantilever, before and after application of a pressure of 100 MPa for 30 min, demonstrated that mother and daughter cells have different responses. Daughter cells were more sensitive to the effects of HHP, presenting lower average Ra (arithmetic roughness), Rz (ten-point average roughness), and Rq (root-mean-square roughness) after exposure to high pressure. Better adaptation to stress in mother cells leads to higher cell wall resistance and, therefore, to better protection.

Complete genome sequence and analysis of a Saccharomyces cerevisiae strain used for sugarcane spirit production.

Distillation of fermented sugarcane juice produces both rum and cachaça, significant sources of revenue in Brazil and elsewhere. In this study, we provide a genomic analysis of a Saccharomyces cerevisiae strain isolated from a cachaça distillery in Brazil. We determined the complete genome sequence of a strain with high flocculation capacity, high tolerance to ethanol, osmotic and heat shock stress and high fermentation rates and compared the sequence with that of the reference S288c genome as well as those of two other cachaça strains. Single-nucleotide polymorphism analysis identified alterations in genes involved in nitrogen and organic compound metabolism, integrity of organelles and ion homeostasis. The strain exhibited fragmentation of several flocculation genes relative to the reference genome, as well as loss of a stop codon in the FLO8 gene, which encodes a transcription factor required for FLO gene expression. The strain contained no genes not present in the reference genome strain but did lack several genes, including asparaginase genes, maltose utilization loci, and several genes from the tandem array of the DUP240 family. The three cachaça strains lacked different sets of genes, but the asparaginase genes and several of the DUP240 genes were common deficiencies. This study provides new insights regarding the selective pressure of sugarcane fermentation on the genome of yeast strains and offers additional genetic resources for modern synthetic biology and genome editing tools.

Recombinogenic, genotoxic, and cytotoxic effects of azathioprine using in vivo assays.

Azathioprine (Aza) is a purine antimetabolite immunosuppressant that is widely employed for immunosuppressive therapy in post-transplant recipients or patients with autoimmune diseases. Chronic use of immunosuppressants might produce several side effects, including a high rate of neoplasms in these patients. Considering that genotoxic effects are associated with an increased risk of developing cancer, the aim of this study was to examine the recombinogenic, genotoxic, and cytotoxic effects of Aza using Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster, as well as comet and micronucleus assays in mouse bone marrow cells. Further, the adverse effects of Aza were determined in mouse hepatic and renal tissues using histopathological analysis. Data demonstrated that Aza induced significant increased genotoxicity in D. melanogaster and mouse bone marrow cells at all concentrations tested. Homologous recombination was the predominant genotoxic event noted for the first time to be initiated by Aza in SMART. In histopathological analysis, Aza did not show any marked toxic activity in mouse hepatic and renal tissues. Therefore, the high rate of neoplasms reported in patients with long-term use of Aza may be attributed, at least partially, to the genotoxic action of this drug.

Battle of Three: The Curious Case of Papaya Sticky Disease.

Among the most serious problems in papaya production are the viruses associated with papaya ringspot and papaya sticky disease (PSD). PSD concerns producers worldwide because its symptoms are extremely aggressive and appear only after flowering. As no resistant cultivar is available, several disease management strategies have been used in affected countries, such as the use of healthy seeds, exclusion of the pathogen, and roguing. In the 1990s, a dsRNA virus, papaya meleira virus (PMeV), was identified in Brazil as the causal agent of PSD. However, in 2016 a second virus, papaya meleira virus 2 (PMeV2), with an ssRNA genome, was also identified in PSD plants. Only PMeV is detected in asymptomatic plants, whereas all symptomatic plants contain both viral RNAs separately packaged in particles formed by the PMeV capsid protein. PSD also affects papaya plants in Mexico, Ecuador, and Australia. PMeV2-like viruses have been identified in the affected plants, but the partner virus(es) in these countries are still unknown. In Brazil, PMeV and PMeV2 reside in laticifers that promote spontaneous latex exudation, resulting in the affected papaya fruit's sticky appearance. Genes modulated in plants affected by PSD include those involved in reactive oxygen species and salicylic acid signaling, proteasomal degradation, and photosynthesis, which are key plant defenses against PMeV complex infection. However, the complete activation of the defense response is impaired by the expression of negative effectors modulated by the virus. This review presents a summary of the current knowledge of the Carica papaya-PMeV complex interaction and management strategies.

First Report of HLB Causal Agent in Psyllid in State of Bahia, Brazil.

The state of Bahia ranks fourth in the national rank for citrus production, and the region of Chapada Diamantina is emerging an important producer of orange for fresh fruit market. Huanglongbing (HLB) is the major phytosanitary threat to Bahia citriculture. In Brazil, the disease was first reported in 2004 in São Paulo state. The bacterium Candidatus Liberibacter asiaticus (CLas) is one of the causal agents of HLB, which is transmitted by the insect vector Diaphorina citri Kuwayama (Hemiptera: Liviidae). Bahia is a HLB-free area; therefore, it is essential to monitor its citrus-producing areas to early detect any possible introduction of the CLas. This study aimed to monitor the presence of the bacteria in the insect vector. Diaphorina citri samples were collected from 2011 to 2014 in different cities located at Chapada Diamantina region and tested by qPCR for the presence of CLas. Three samples were considered positive to bacterium, and all from psyllids collected on Murraya paniculata in the city of Seabra.

Atividade antibacteriana de nanopartículas de polipirrol diante de Staphylococcus aureus isolados de amostras de leite de vacas e cabras com mastite / Antibacterial behavior of polypyrrole nanoparticles against Staphylococcus aureus isolated from cows and goats with mastitis

The aim of the present study was to evaluate the antibacterial behavior of polypyrrole nanoparticles (PPy-NPs) in water against biofilm producer or not S. aureus isolated from cows and goats with mastitis. One hundred and thirty-eight isolates of S. aureus were initially evaluated for biofilm formation by spectrophotometry in microplates. In addition, the minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) of PPy-NPs in water for planktonic S. aureus were determined. From the bovine samples analyzed, 5 (4.46%) S. aureus isolates showed a strong biofilm production, 17 (15.18%) moderate production, 36 (32.14%) with weak production and 54 (48.21%) did not produce biofilms. Strains from goats (26) showed no biofilm production in 18 (69.23%) strains and weak biofilm production in 8 (30.76%) strains. The MIC and MBC of S. aureus to PPy-NPs were found in the same concentration (125搭/mL) in all strains tested, regardless of biofilm production or not. This finding provides a new insight into the interaction between PPy-NPs and S. aureus, and will offer potential benefits for the control of mastitis.(AU)

Atividade antibacteriana de nanopartículas de polipirrol diante de Staphylococcus aureus isolados de amostras de leite de vacas e cabras com mastite / Antibacterial behavior of polypyrrole nanoparticles against Staphylococcus aureus isolated from cows and goats with mastitis

The aim of the present study was to evaluate the antibacterial behavior of polypyrrole nanoparticles (PPy-NPs) in water against biofilm producer or not S. aureus isolated from cows and goats with mastitis. One hundred and thirty-eight isolates of S. aureus were initially evaluated for biofilm formation by spectrophotometry in microplates. In addition, the minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) of PPy-NPs in water for planktonic S. aureus were determined. From the bovine samples analyzed, 5 (4.46%) S. aureus isolates showed a strong biofilm production, 17 (15.18%) moderate production, 36 (32.14%) with weak production and 54 (48.21%) did not produce biofilms. Strains from goats (26) showed no biofilm production in 18 (69.23%) strains and weak biofilm production in 8 (30.76%) strains. The MIC and MBC of S. aureus to PPy-NPs were found in the same concentration (125搭/mL) in all strains tested, regardless of biofilm production or not. This finding provides a new insight into the interaction between PPy-NPs and S. aureus, and will offer potential benefits for the control of mastitis.(AU)

Serum metabolomic fingerprints of lambs fed chitosan and its association with performance and meat quality traits.

Chitosan (CHI) is a natural biopolymer with antimicrobial, anti-inflammatory, antioxidant and digestive modulatory effects, which can be used in the ruminant diet to replace antibiotics. The aim of this study was to evaluate the effects of CHI on lamb growth traits, nutrients digestibility, muscle and fatty deposition, meat fatty acid (FA) profile, meat quality traits and serum metabolome. Thirty 30-month-old male lambs, half Suffolk and half Dorper, with an average BW of 21.65 ± 0.86 kg, were fed in a feedlot system for a total of 70 days. The lambs were separated into two groups according to the diet: the control (CON) group which received the basal diet and the CHI group which received the basal diet with the addition of CHI as 2 g/kg of DM in the diet. Lambs supplemented with CHI had a greater (P < 0.05) final BW, DM intake, final body metabolic weight (P < 0.05) and lower residual feed intake than the CON group. Animals fed CHI had a greater (P < 0.05) starch digestibility at 14 and 28 days, average daily gain at 14, 42 and 56 days, greater feed efficiency at 28 days and feed conversation at 14 and 42 days in feedlot. Most of the carcass traits were not affected (P > 0.05) by the treatment; however, the CHI supplementation improved (P < 0.05) dressing and longissimus muscle area. The treatments had no effect (P > 0.05) on the meat colour and other quality measurements. Meat from the CHI-fed lambs had a greater concentration (P < 0.05) of oleic-cis-9 acid, linoleic acid, linolenic-trans-6 acid, arachidonic acid and eicosapentaenoic acid. According to the variable importance in projection score, the most important metabolites to differentiate between the CON and the CHI group were hippurate, acetate, hypoxanthine, arginine, malonate, creatine, choline, myo-inositol, 2-oxoglutarate, alanine, glycerol, carnosine, histidine, glutamate and 3-hydroxyisobutyrate. Similarly, fold change (FC) analysis highlighted succinate (FC = 1.53), arginine (FC = 1.51), hippurate (FC = 0.68), myo-inositol (FC = 1.48), hypoxanthine (FC = 1.45), acetate (FC = 0.73) and malonate (FC = 1.35) as metabolites significantly different between groups. In conclusion, the present data showed that CHI changes the muscle metabolism improving muscle mass deposition, the lamb's performance and carcass dressing. In addition, CHI led to an alteration in the FA metabolism, changes in the meat FA profile and improvements in meat quality.

A metal-free blue chromophore derived from plant pigments.

Blue natural pigments are rare, especially among plants. However, flowering species that evolved to attract Hymenoptera pollinators are colored by blue anthocyanin-metal complexes. Plants lacking anthocyanins are pigmented by betalains but are unable to produce blue hues. By extending the π-system of betalains, we designed a photostable and metal-free blue dye named BeetBlue that did not show toxicity to human hepatic and retinal pigment epithelial cells and does not affect zebrafish embryonal development. This chiral dye can be conveniently synthesized from betalamic acid obtained from hydrolyzed red beetroot juice or by enzymatic oxidation of l-dopa. BeetBlue is blue in the solid form and in solution of acidified polar molecular solvents, including water. Its capacity to dye natural matrices makes BeetBlue the prototype of a new class of low-cost bioinspired chromophores suitable for a myriad of applications requiring a blue hue.

Avaliação do modelo NRC para predição do consumo de matéria seca por vacas leiteiras manejadas em pastos tropicais / NCR Model Evaluation for prediction of dry matter intake by dairy cows managed in tropical pastures

Objetivou-se avaliar o poder preditivo do modelo do National Research Council (NRC) para gado leiteiro em estimar o consumo de matéria seca (CMS) por vacas mestiças, em pastagens tropicais. Foi efetuada uma análise conjunta de cinco estudos, contemplando três forrageiras. Foram avaliadas 132 estimativas individuais do CMS observado (CMSObs), obtidas por meio do indicador externo Cr2O3. O CMS também foi predito por meio do software do NRC (CMSPred), que, por sua vez, foi abastecido com inputs referentes aos animais e ao ambiente de criação. Os valores de CMSPred (12,7±1,6kg/d) foram semelhantes aos de CMSObs (12,3±3,3kg/d). Foram obtidas as seguintes estimativas da avaliação do poder preditivo do modelo: viés médio (-0,419kg/d), coeficiente de determinação (0,029), coeficiente de correlação (0,17; P=,051), quadrado médio do erro de predição (11,844±20,034), fator de eficiência do modelo (-0,081), coeficiente de determinação do modelo (4,1032) e fator de correção do viés (0,767). A comparação entre CMSObs e CMSPred permitiu identificar a tendência de superestimação das predições se considerado o ajuste por meio de regressão robusta para o modelo linear simples sem intercepto. Nas condições avaliadas, o modelo produz predições de CMS com satisfatória exatidão, porém com baixa precisão.(AU)

The aim of the present study was to evaluate the predictive power of estimating the dry matter intake (DMI) of crossbred cows on tropical pastures by the National Research Council (NRC) equation for dairy cattle. A joint analysis of five studies covering three forages was performed in which 132 individual estimates of observed DMI obtained through Cr2O3 as a marker. DMI was also predicted from the NRC (DMIPred) software with inputs concerning animals and breeding environment of the studies used. Predicted DMIPred average values (12.7±1.6kg/d) were similar to the observed DMIObs ones (12.3±3.3kg/d). We obtained the following estimates of the evaluation of the predictive power of the model: average bias (- 0.419kg/d), coefficient of determination (0.029), Person's correlation coefficient (0.17, P= 0.051), mean square error of prediction (11,844±20,034), model efficiency factor (- 0.081), coefficient of determination (4.1032), and bias correction factor (0.767). The comparison between DMIObs and DMIPred values allowed the identification of the overestimating tendency of the predictions demonstrated by the robust regression fit of the simple linear no intercept model. Nevertheless, the model yields predictions with satisfactory accuracy, but with low precision.(AU)

Avaliação do modelo NRC para predição do consumo de matéria seca por vacas leiteiras manejadas em pastos tropicais / NCR Model Evaluation for prediction of dry matter intake by dairy cows managed in tropical pastures

Objetivou-se avaliar o poder preditivo do modelo do National Research Council (NRC) para gado leiteiro em estimar o consumo de matéria seca (CMS) por vacas mestiças, em pastagens tropicais. Foi efetuada uma análise conjunta de cinco estudos, contemplando três forrageiras. Foram avaliadas 132 estimativas individuais do CMS observado (CMSObs), obtidas por meio do indicador externo Cr2O3. O CMS também foi predito por meio do software do NRC (CMSPred), que, por sua vez, foi abastecido com inputs referentes aos animais e ao ambiente de criação. Os valores de CMSPred (12,7±1,6kg/d) foram semelhantes aos de CMSObs (12,3±3,3kg/d). Foram obtidas as seguintes estimativas da avaliação do poder preditivo do modelo: viés médio (-0,419kg/d), coeficiente de determinação (0,029), coeficiente de correlação (0,17; P=,051), quadrado médio do erro de predição (11,844±20,034), fator de eficiência do modelo (-0,081), coeficiente de determinação do modelo (4,1032) e fator de correção do viés (0,767). A comparação entre CMSObs e CMSPred permitiu identificar a tendência de superestimação das predições se considerado o ajuste por meio de regressão robusta para o modelo linear simples sem intercepto. Nas condições avaliadas, o modelo produz predições de CMS com satisfatória exatidão, porém com baixa precisão.(AU)

The aim of the present study was to evaluate the predictive power of estimating the dry matter intake (DMI) of crossbred cows on tropical pastures by the National Research Council (NRC) equation for dairy cattle. A joint analysis of five studies covering three forages was performed in which 132 individual estimates of observed DMI obtained through Cr2O3 as a marker. DMI was also predicted from the NRC (DMIPred) software with inputs concerning animals and breeding environment of the studies used. Predicted DMIPred average values (12.7±1.6kg/d) were similar to the observed DMIObs ones (12.3±3.3kg/d). We obtained the following estimates of the evaluation of the predictive power of the model: average bias (- 0.419kg/d), coefficient of determination (0.029), Person's correlation coefficient (0.17, P= 0.051), mean square error of prediction (11,844±20,034), model efficiency factor (- 0.081), coefficient of determination (4.1032), and bias correction factor (0.767). The comparison between DMIObs and DMIPred values allowed the identification of the overestimating tendency of the predictions demonstrated by the robust regression fit of the simple linear no intercept model. Nevertheless, the model yields predictions with satisfactory accuracy, but with low precision.(AU)

The molecular landscape of osteogenesis imperfecta in a Brazilian tertiary service cohort.

We have sought the molecular diagnosis of OI in 38 Brazilian cases through targeted sequencing of 15 candidate genes. While 71% had type 1 collagen-related OI, defects in FKBP10, PLOD2 and SERPINF1, and a potential digenic P3H1/WNT1 interaction were prominent causes of OI in this underrepresented population. INTRODUCTION: Defects in type 1 collagen reportedly account for 85-90% of osteogenesis imperfecta (OI) cases, but most available molecular data has derived from Sanger sequencing-based approaches in developed countries. Massively parallel sequencing (MPS) allows for systematic and comprehensive analysis of OI genes simultaneously. Our objective was to obtain the molecular diagnosis of OI in a single Brazilian tertiary center cohort. METHODS: Forty-nine individuals (84% adults) with a clinical diagnosis of OI, corresponding to 30 sporadic and 8 familial cases, were studied. Sixty-three percent had moderate to severe OI, and consanguinity was common (26%). Coding regions and 25-bp boundaries of 15 OI genes (COL1A1, COL1A2, IFITM5 [plus 5'UTR], SERPINF1, CRTAP, P3H1, PPIB, SERPINH1, FKBP10, PLOD2, BMP1, SP7, TMEM38B, WNT1, CREB3L1) were analyzed by targeted MPS and variants of interest were confirmed by Sanger sequencing or SNP array. RESULTS: A molecular diagnosis was obtained in 97% of cases. COL1A1/COL1A2 variants were identified in 71%, whereas 26% had variants in other genes, predominantly FKBP10, PLOD2, and SERPINF1. A potential digenic interaction involving P3H1 and WNT1 was identified in one case. Phenotypic variability with collagen defects could not be explained by evident modifying variants. Four consanguineous cases were associated to heterozygous COL1A1/COL1A2 variants, and two nonconsanguineous cases had compound PLOD2 heterozygosity. CONCLUSIONS: Novel disease-causing variants were identified in 29%, and a higher proportion of non-collagen defects was seen. Obtaining a precise diagnosis of OI in underrepresented populations allows expanding our understanding of its molecular landscape, potentially leading to improved personalized care in the future.