Exploring the Longissimus Muscle: Unraveling its Correlation with Meat Quality in Bos indicus and Crossbred Bulls.

This study investigated muscle tissue in Bos indicus and crossbred bulls to explain differences in meat quality traits. Carcass traits, meat quality parameters, and biochemical and molecular investigations of myofibrillar proteins are described. Methods for evaluating pH, intramuscular fat (IMF), meat color (L*, a*, b*), water losses, tenderness, and molecular biology assays have been outlined. Specific procedures detailing calibration, sample preparation, and data analysis for each method are described. These include techniques such as infrared spectroscopy for IMF content, objective tenderness assessment, and electrophoretic separation of MyHC isoforms. Color parameters were highlighted as potential tools for predicting beef tenderness, a crucial quality trait influencing consumer decisions. The study employed the Warner-Bratzler shear force (WBSF) method, revealing values of 4.68 and 4.23 kg for Nellore and Angus-Nellore (P < 0.01), respectively. Total cooking losses and biochemical analyses, including myofibril fragmentation index (MFI), provided insights into tenderness variations. Muscle fiber types, particularly myosin heavy chain (MyHC) isoforms, were investigated, with a notable absence of MyHC-IIb isoform in the studied Zebu animals. The relationship between MyHC-I and meat tenderness revealed divergent findings in the literature, highlighting the complexity of this association. Overall, the study provides comprehensive insights into the factors influencing meat quality in Bos indicus and crossbred (Bos taurus × Bos indicus) bulls, offering valuable information for the beef industry.

α-Tricalcium phosphate cement reinforced with silk fibroin: A high strength biomimetic bone cement with chloride-substituted hydroxyapatite.

In the past decades, bone defects have become an increasing factor in the development of disability in patients, impacting their quality of life. Large bone defects have minor chances to self-repair, requiring surgical intervention. Therefore, α-TCP-based cements are rigorously studied for the development of bone filling and replacement applications due to the possibility of application in minimally invasive procedures. However, α-TCP-based cements do not present adequate mechanical properties for most orthopedic applications. The aim of this study is to develop a biomimetic α-TCP cement reinforced with 0.250-1.000 wt% of silk fibroin using non-dialyzed SF solutions. Samples with SF additions higher than 0.250 wt% presented complete transformation of the α-TCP to a biphasic CDHA/HAp-Cl material, which could enhance the osteoconductivity of the material. Samples reinforced with concentrations of 0.500 wt% SF showed an increase of 450% of the fracture toughness and 182% of the compressive strength of the control sample, even with 31.09% porosity, which demonstrates good coupling between the SF and the CPs. All samples reinforced with SF showed a microstructure with smaller needle-like crystals when compared to the control sample, which possibly contributed to the material's reinforcement. Moreover, the composition of reinforced samples did not affect the cytotoxicity of the CPCs and enhanced the cell viability presented by the CPC without SF addition. Hence, biomimetic CPCs with mechanical reinforcement through the addition of SF were successfully obtained through the developed methodology, with the potential to be further evaluated as a suitable material for bone regeneration.

Phytochemical profile, in vitro activities, and toxicity of optimized Eugenia uniflora extracts / Perfil fitoquímico, actividades in vitro y toxicidad de extractos optimizados de Eugenia uniflora

In this study, we investigated the influence of mixture design on the chemical profile of Eugenia unifloraleaves, evaluating the antioxidant and antimicrobial activities, the toxic and hemolytic potential, with the focus on the improvement of the polyphenol's extraction for incorporation of the extract in semi-solid forms with antifungal action. The chemical analysis was evaluated by UV-Vis and HPLC. The antimicrobial, antioxidant, and hemolytic activities were monitored. The flavonoid content ranged from 2.63-7.98 %w/w and tannins from 5.42-18.29 %w/w. The extract consisted of gallic acid (0.09-1.29%; w/w), ellagic acid (0.09-0.37%; w/w), and myricitrin (0.18-1.20%; w/w). The most successful solvent system with the highest level of active extract was water: ethanol: propylene glycol. The extracts showed fungicidal properties (3.9 µg/mL), high antioxidant activity (IC50: 9.50 µg/mL), and low toxicity. These solvent mixtures can improve the in vitro bioactivities when compared to pure solvents and this result demonstrates the importance of mixture designs as useful tools for creating high-quality herbal products and elucidate the potential of E. uniflora glycolic extracts as active herbal pharmaceutical ingredients in topical delivery systems.

En este estudio investigamos la influencia del diseño de mezclas en el perfil químico de hojas de Eugenia uniflora, evaluando las actividades antioxidantes y antimicrobianas, el potencial tóxico y hemolítico, con el foco en la mejora de la extracción de polifenoles para la incorporación del extracto en formas semi-sólidas con acción antifúngica. El análisis químico se evaluó mediante UV-Vis y HPLC. Se monitorizaron las actividades antimicrobianas, antioxidantes y hemolíticas. El contenido de flavonoides osciló entre 2,63 y 7,98% p/p and taninos de 5,42-18,29% p/p. El extracto consistió en ácido gálico (0.09-1.29%; p/p), ácido elágico (0.09-0.37%; p/p) y miricitrina (0.18-1.20%; p/p). El sistema de disolventes más exitoso con el nivel más alto de extracto activo fue agua: etanol: propilenglicol. Los extractos mostraron propiedades fungicidas (3.9 µg/mL), alta actividad antioxidante (IC50: 9.50 µg/mL) y baja toxicidad. Estas mezclas de disolventes pueden mejorar las bioactividades in vitro en comparación con los disolventes puros y este resultado demuestra la importancia de los diseños de mezclas como herramientas útiles para crear productos a base de hierbas de alta calidad y dilucidar el potencial de los extractos glicólicos de E. uniflora como ingredientes farmacéuticos a base de hierbas en sistemas de entrega activos.

Spliced genes in muscle from Nelore Cattle and their association with carcass and meat quality.

Transcript data obtained by RNA-Seq were used to identify differentially expressed alternatively spliced genes in ribeye muscle tissue between Nelore cattle that differed in their ribeye area (REA) or intramuscular fat content (IF). A total of 166 alternatively spliced transcripts from 125 genes were significantly differentially expressed in ribeye muscle between the highest and lowest REA groups (p ≤ 0.05). For animals selected on their IF content, 269 alternatively spliced transcripts from 219 genes were differentially expressed in ribeye muscle between the highest and lowest IF animals. Cassette exons and alternative 3' splice sites were the most frequently found alternatively spliced transcripts for REA and IF content. For both traits, some differentially expressed alternatively spliced transcripts belonged to myosin and myotilin gene families. The hub transcripts were identified for REA (LRRFIP1, RCAN1 and RHOBTB1) and IF (TRIP12, HSPE1 and MAP2K6) have an important role to play in muscle cell degradation, development and motility. In general, transcripts were found for both traits with biological process GO terms that were involved in pathways related to protein ubiquitination, muscle differentiation, lipids and hormonal systems. Our results reinforce the biological importance of these known processes but also reveal new insights into the complexity of the whole cell muscle mRNA of Nelore cattle.

Oxidative stress responses of juvenile tambaqui Colossoma macropomum after short-term anesthesia with benzocaine and MS-222.

The present study aimed to evaluate the effects of benzocaine and tricaine methanesulfonate on oxidative stress parameters of juvenile tambaqui tissues. Fish (n=80) were anesthetized with benzocaine (100 mg L-1) or tricaine (240 mg L-1) and two control groups were used (non-anesthetized fish and fish exposed to ethanol-only). After anesthetic induction 10 fish/anesthetic were euthanized after 3, 12 and 24 hours post-anesthesia and tissue samplings (gills, liver and brain) were performed. Samples were submitted to analyses of enzyme activity glutathione-S-transferase (GST), cellular lipid peroxidation (TBARS) and total antioxidant capacity (ACAP). ACAP increased in gills of benzocaine treatment after 12 hours. The liver showed a reduction in ACAP of tricaine treatment after 12 hours. Both anesthetic treatments showed an increase of ACAP at 24 hours compared to control group. The activity of the GST enzyme increased in the gills for treatments benzocaine and tricaine after 3 and 12 hours. Liver showed increased GST activity (benzocaine after 24 hours and tricaine after 3 and 24 hours). Lipid damage decreased in gills (both anesthetics) and brain (tricaine) after 24 hours. The results demonstrate that benzocaine and tricaine did not cause oxidative damage in juvenile tambaqui under the experimental conditions herein established.

In vitro evaluation of poly (lactic-co-glycolic acid)/polyisoprene fibers for soft tissue engineering.

The polymeric blend of poly (lactic-co-glycolic acid) (PLGA) and polyisoprene (PI) has recently been explored for application as stents for tracheal stenosis and spring for the treatment of craniosynostosis. From the positive results presented in other biomedical applications comes the possibility of investigating the application of this material as scaffold for tissue engineering (TE), acquiring a deeper knowledge about the polymeric blend by exploring a new processing technique while attending to the most fundamental demands of TE scaffolds. PLGA/PI was processed into randomly oriented microfibers through the dripping technique and submitted to physical-chemical and in vitro characterization. The production process of fibers did not show an effect over the polymer's chemical composition, despite the fact that PLGA and PI were observed to be immiscible. Mechanical assays reinforce the suitability of these scaffolds for soft tissue applications. Skeletal muscle cells demonstrated increases in metabolic activity and proliferation to the same levels of the control group. Human dermal fibroblasts didn't show the same behaviour, but presented cell growth with the same development profile as presented in the control group. It is plausible to believe that PLGA/PI fibrous three-dimensional scaffolds are suitable for applications in soft tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2581-2591, 2017.

Oxidative stress responses of juvenile tambaqui Colossoma macropomum after short-term anesthesia with benzocaine and MS-222

ABSTRACT The present study aimed to evaluate the effects of benzocaine and tricaine methanesulfonate on oxidative stress parameters of juvenile tambaqui tissues. Fish (n=80) were anesthetized with benzocaine (100 mg L-1) or tricaine (240 mg L-1) and two control groups were used (non-anesthetized fish and fish exposed to ethanol-only). After anesthetic induction 10 fish/anesthetic were euthanized after 3, 12 and 24 hours post-anesthesia and tissue samplings (gills, liver and brain) were performed. Samples were submitted to analyses of enzyme activity glutathione-S-transferase (GST), cellular lipid peroxidation (TBARS) and total antioxidant capacity (ACAP). ACAP increased in gills of benzocaine treatment after 12 hours. The liver showed a reduction in ACAP of tricaine treatment after 12 hours. Both anesthetic treatments showed an increase of ACAP at 24 hours compared to control group. The activity of the GST enzyme increased in the gills for treatments benzocaine and tricaine after 3 and 12 hours. Liver showed increased GST activity (benzocaine after 24 hours and tricaine after 3 and 24 hours). Lipid damage decreased in gills (both anesthetics) and brain (tricaine) after 24 hours. The results demonstrate that benzocaine and tricaine did not cause oxidative damage in juvenile tambaqui under the experimental conditions herein established.

Genome-Wide Association Study of Meat Quality Traits in Nellore Cattle.

The objective of this study was to identify genomic regions that are associated with meat quality traits in the Nellore breed. Nellore steers were finished in feedlots and slaughtered at a commercial slaughterhouse. This analysis included 1,822 phenotypic records of tenderness and 1,873 marbling records. After quality control, 1,630 animals genotyped for tenderness, 1,633 animals genotyped for marbling, and 369,722 SNPs remained. The results are reported as the proportion of variance explained by windows of 150 adjacent SNPs. Only windows with largest effects were considered. The genomic regions were located on chromosomes 5, 15, 16 and 25 for marbling and on chromosomes 5, 7, 10, 14 and 21 for tenderness. These windows explained 3,89% and 3,80% of the additive genetic variance for marbling and tenderness, respectively. The genes associated with the traits are related to growth, muscle development and lipid metabolism. The study of these genes in Nellore cattle is the first step in the identification of causal mutations that will contribute to the genetic evaluation of the breed.

Preparation and characterization of electrical conductive PVA based materials for peripheral nerve tube-guides.

Peripheral nerve regeneration is a serious clinical problem. Presently, there are several nerve tube-guides available in the market, however with some limitations. The goal of this work was the development of a biomaterial with high electrical conductivity to produce tube-guides for nerve regeneration after neurotmesis injuries whenrver an end-to-end suture without tension is not possible. A matrix of poly(vinyl alcohol) (PVA) was used loaded with the following electrical conductive materials: COOH-functionalized multiwall carbon nanotubes (MWCNTs), poly(pyrrole) (PPy), magnesium chloride (MgCl2 ), and silver nitrate (AgNO3 ). The tube-guide production was carried out by a freezing/thawing process (physical crosslinking) with a final annealing treatment. After producing the tube-guide for nerve regeneration, the physicochemical characterization was performed. The most interesting results were achieved by loading PVA with 0.05% of PPy or COOH- functionalized CNTs. These tubes combined the electrical conductivity of carbon nanotubes (CNTs) and PPy with the biocompatibility of PVA matrix, with potential clinical application for nerve regeneration. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1981-1987, 2016.

Genomic prediction of breeding values for carcass traits in Nellore cattle.

BACKGROUND: The objective of this study was to evaluate the accuracy of genomic predictions for rib eye area (REA), backfat thickness (BFT), and hot carcass weight (HCW) in Nellore beef cattle from Brazilian commercial herds using different prediction models. METHODS: Phenotypic data from 1756 Nellore steers from ten commercial herds in Brazil were used. Animals were offspring of 294 sires and 1546 dams, reared on pasture, feedlot finished, and slaughtered at approximately 2 years of age. All animals were genotyped using a 777k Illumina Bovine HD SNP chip. Accuracy of genomic predictions of breeding values was evaluated by using a 5-fold cross-validation scheme and considering three models: Bayesian ridge regression (BRR), Bayes C (BC) and Bayesian Lasso (BL), and two types of response variables: traditional estimated breeding value (EBV), and phenotype adjusted for fixed effects (Y*). RESULTS: The prediction accuracies achieved with the BRR model were equal to 0.25 (BFT), 0.33 (HCW) and 0.36 (REA) when EBV was used as response variable, and 0.21 (BFT), 0.37 (HCW) and 0.46 (REA) when using Y*. Results obtained with the BC and BL models were similar. Accuracies increased for traits with a higher heritability, and using Y* instead of EBV as response variable resulted in higher accuracy when heritability was higher. CONCLUSIONS: Our results indicate that the accuracy of genomic prediction of carcass traits in Nellore cattle is moderate to high. Prediction of genomic breeding values from adjusted phenotypes Y* was more accurate than from EBV, especially for highly heritable traits. The three models considered (BRR, BC and BL) led to similar predictive abilities and, thus, either one could be used to implement genomic prediction for carcass traits in Nellore cattle.

[Establishment of a preclinical neuroblastoma model in immunocompetent mice]. / Establecimiento de un modelo preclínico de neuroblastoma en ratones inmunocompetentes.

AIM: To develop a NB animal model which makes possible studies related to tumor immunity. MATERIALS AND METHODS: Two types of NB cells were used. Cell line 36769 was derived from TH-MYCN+ mouse in which overexpression of the MYCN gene is governed by rat tyrosine hydroxylase promotor. Cell line 4040 was derived from TH-MYCN/ALK mice, which in addition express an activating mutation of ALK gene. For each cell type, 1x106 neurospheres were implanted in 129/SVJ mice (with the same genetic background as donors, n=8), via orthotopic injection in the left suprarenal gland by intraperitoneal approach, through a transverse supraumbilical laparotomy. Daily postsurgical clinical follow-up of the animals was done until they were sacrificed at four weeks. The tumor presence was macroscopically confirmed. The tumoral sample was excised and was processed for cellular immunity and molecular tolerance mediator's studies. The existence of metastasis was investigated by flow cytometry in the spleen, bone marrow and peripheral blood. RESULTS: 1) Orthotopic Neuroblastoma was generated in all the transplanted mice. 2) The tumors were infiltrated by several immune subpopulations, with effector, regulatory and suppressor inmunophenotype. This was similar to the inmunophenotype described in human NB. Furthermore, the molecular mediators of the environment point to a state of protumoral tolerance. CONCLUSION: The orthotopic implantation of NB neurospheres in syngeneic mice has allowed us to generate a NB model in which it has been possible to study the tumor immunity.

OBJETTIVO: Desarrollar un modelo animal de neuroblastoma (NB) que posibilite estudios relacionados con la inmunidad tumoral. MATERIAL Y METODOS: Se utilizaron dos tipos de células NB. La línea 36769 procedía del ratón TH-MYCN+ en el que la sobreexpresión del gen MYCN está gobernada por el promotor de la tirosín hidroxilasa de rata. La línea 4040 procedía de ratones TH-MYCN+/ALK+, que además expresan una mutación activadora del gen ALK. De cada tipo celular se implantaron 1x106 neurosferas en ratones 129/SVJ (mismo fondo genetico que los donantes, n=8), mediante inyección ortotópica en glándula suprarrenal izquierda por abordaje intraperitoneal, a través de laparotomía transversa supraumbilical. Se realizó seguimiento clínico diario postquirúrgico de los animales hasta su sacrificio a las 4 semanas. La presencia de tumor se confirmó macroscópicamente. La pieza tumoral se extirpó y se procesó para estudios de inmunidad celular y mediadores moleculares de tolerancia. Se investigó la existencia de metástasis por citometría de flujo en bazo, médula ósea y sangre periférica. RESULTADOS: 1) En todos los ratones trasplantados se generó NB ortotópico. 2) La pieza tumoral se encontró infiltrada por diversas subpoblaciones inmunes, con inmunofenotipo efector, regulador y supresor, similar a la situación descrita en los NB humanos. Además, los mediadores moleculares del microambiente apuntan a un estado de tolerancia protumoral. CONCLUSIONES: La implantación ortotópica de neurosferas NB en ratones singénicos nos ha permitido generar un modelo de NB en el que ha sido posible estudiar la inmunidad tumoral.

Effects of Human Mesenchymal Stem Cells Isolated from Wharton's Jelly of the Umbilical Cord and Conditioned Media on Skeletal Muscle Regeneration Using a Myectomy Model.

Skeletal muscle has good regenerative capacity, but the extent of muscle injury and the developed fibrosis might prevent complete regeneration. The in vivo application of human mesenchymal stem cells (HMSCs) of the umbilical cord and the conditioned media (CM) where the HMSCs were cultured and expanded, associated with different vehicles to induce muscle regeneration, was evaluated in a rat myectomy model. Two commercially available vehicles and a spherical hydrogel developed by our research group were used. The treated groups obtained interesting results in terms of muscle regeneration, both in the histological and in the functional assessments. A less evident scar tissue, demonstrated by collagen type I quantification, was present in the muscles treated with HMSCs or their CM. In terms of the histological evaluation performed by ISO 10993-6 scoring, it was observed that HMSCs apparently have a long-term negative effect, since the groups treated with CM presented better scores. CM could be considered an alternative to the in vivo transplantation of these cells, as it can benefit from the local tissue response to secreted molecules with similar results in terms of muscular regeneration. Searching for an optimal vehicle might be the key point in the future of skeletal muscle tissue engineering.

Promoting nerve regeneration in a neurotmesis rat model using poly(DL-lactide-ε-caprolactone) membranes and mesenchymal stem cells from the Wharton's jelly: in vitro and in vivo analysis.

In peripheral nerves MSCs can modulate Wallerian degeneration and the overall regenerative response by acting through paracrine mechanisms directly on regenerating axons or upon the nerve-supporting Schwann cells. In the present study, the effect of human MSCs from Wharton's jelly (HMSCs), differentiated into neuroglial-like cells associated to poly (DL-lactide-ε-caprolactone) membrane, on nerve regeneration, was evaluated in the neurotmesis injury rat sciatic nerve model. Results in vitro showed successful differentiation of HMSCs into neuroglial-like cells, characterized by expression of specific neuroglial markers confirmed by immunocytochemistry and by RT-PCR and qPCR targeting specific genes expressed. In vivo testing evaluated during the healing period of 20 weeks, showed no evident positive effect of HMSCs or neuroglial-like cell enrichment at the sciatic nerve repair site on most of the functional and nerve morphometric predictors of nerve regeneration although the nociception function was almost normal. EPT on the other hand, recovered significantly better after HMSCs enriched membrane employment, to values of residual functional impairment compared to other treated groups. When the neurotmesis injury can be surgically reconstructed with an end-to-end suture or by grafting, the addition of a PLC membrane associated with HMSCs seems to bring significant advantage, especially concerning the motor function recovery.

Role of ionotropic glutamatergic receptors and nitric oxide in the effects of flutriafol, a triazole fungicide, on the in vivo striatal dopamine release.

Flutriafol is a triazole fungicide that induces spontaneous and depolarization-stimulated release of dopamine from rat striatum, although the neurochemical mechanism by which this fungicide induces this effect is unknown. The purpose of the present work was to assess the implication of ionotropic glutamatergic receptors and nitric oxide (NO) production in the flutriafol-induced dopamine release from rat striatum. To this, we have used non-competitive antagonists of NMDA (dizocilpine, MK-801), and (AMPA)/kainate (6-cyano-7-nitroquinoxaline-2,3-dione, CNQX) receptors, or nitric oxide synthase (NOS) inhibitors (Nomega-nitro-L-arginine -L-NARG - and 7-nitro-indazol - 7-NI), to study the striatal dopamine release induced by flutriafol. Intrastriatal infusion of 6 mM flutriafol increased the dopamine levels to 984 ± 141%, with respect to basal levels. Infusion of flutriafol (6 mM) in MK-801 (500 µM) or CNQX (500 µM) pretreated animals, increased striatal dopamine levels to 489 ± 74% and 477 ± 78%, with respect to basal levels, respectively, these increases being 50.3% and 51.5% smaller than those induced by flutriafol in non-pretreated animals. Infusion of flutriafol (6 mM) in L-NARG (1 mM) or 7-NI (100 µM) pretreated animals, increased the extracellular dopamine levels to 400 ± 88.5 and 479 ± 69.4%, with respect to basal levels, respectively, these increases being 59.3 and 51% smaller than those induced by flutriafol in non-pretreated animals. In summary, flutriafol appears to act, at least in part, through an overstimulation of NMDA receptors with possible NO production to induce dopamine release, and the administration of NMDA and AMPA/kainate receptor antagonists and NOS inhibitors protects against flutriafol-induced dopamine release from rat striatum.

Use of poly(DL-lactide-ε-caprolactone) membranes and mesenchymal stem cells from the Wharton's jelly of the umbilical cord for promoting nerve regeneration in axonotmesis: in vitro and in vivo analysis.

Cellular systems implanted into an injured nerve may produce growth factors or extracellular matrix molecules, modulate the inflammatory process and eventually improve nerve regeneration. In the present study, we evaluated the therapeutic value of human umbilical cord matrix MSCs (HMSCs) on rat sciatic nerve after axonotmesis injury associated to Vivosorb® membrane. During HMSCs expansion and differentiation in neuroglial-like cells, the culture medium was collected at 48, 72 and 96 h for nuclear magnetic resonance (NMR) analysis in order to evaluate the metabolic profile. To correlate the HMSCs ability to differentiate and survival capacity in the presence of the Vivosorb® membrane, the [Ca(2+)]i of undifferentiated HMSCs or neuroglial-differentiated HMSCs was determined by the epifluorescence technique using the Fura-2AM probe. The Vivosorb® membrane proved to be adequate and used as scaffold associated with undifferentiated HMSCs or neuroglial-differentiated HMSCs. In vivo testing was carried out in adult rats where a sciatic nerve axonotmesis injury was treated with undifferentiated HMSCs or neuroglial differentiated HMSCs with or without the Vivosorb® membrane. Motor and sensory functional recovery was evaluated throughout a healing period of 12 weeks using sciatic functional index (SFI), extensor postural thrust (EPT), and withdrawal reflex latency (WRL). Stereological analysis was carried out on regenerated nerve fibers. In vitro investigation showed the formation of typical neuroglial cells after differentiation, which were positively stained for the typical specific neuroglial markers such as the GFAP, the GAP-43 and NeuN. NMR showed clear evidence that HMSCs expansion is glycolysis-dependent but their differentiation requires the switch of the metabolic profile to oxidative metabolism. In vivo studies showed enhanced recovery of motor and sensory function in animals treated with transplanted undifferentiated and differentiated HMSCs that was accompanied by an increase in myelin sheath. Taken together, HMSC from the umbilical cord Wharton jelly might be useful for improving the clinical outcome after peripheral nerve lesion.

A new overtraining protocol for mice based on downhill running sessions.

1. The purpose of the present study was to verify whether a downhill running protocol was able to induce non-functional overreaching in > 75% of mice. 2. Mice were divided into control (C), trained (TR) and overtrained (OTR) groups. Bodyweight and food intake were recorded weekly. The incremental load test (ILT) and the exhaustive test (ET) were used to measure performance before and after aerobic training and overtraining protocols. 3. Although the bodyweight of the OTR group was lower than that of the C group at the end of Week 7, the food intake of the OTR group was higher than that of the C and TR groups at the end of Week 8. Evaluation of results from the ILT and ET revealed significant intra- and inter-group differences: whereas the parameters measured by both tests increased significantly in the TR group, they were significantly decreased in the OTR group. 4. In conclusion, this new overtraining protocol based on downhill running sessions induced non-functional overreaching in 100% of mice.

[Noninvasive positive pressure ventilation in postoperative period of tracheal surgery]. / Ventilación con presión positiva no invasiva en el postoperatorio de cirugía traqueal.

OBJECTIVES: Reconstructive surgery of the airway often means prolonged periods of intubation during the post-operatory period, increasing the needs for drugs and favoring the appearance of infectious complications. We present an original system of ventilatory support with non-invasive positive pressure ventilation (NIPPV) using in patients subjected to reconstructive surgery of the airway. PATIENTS AND METHODS: A retrospective study in patients undergoing reconstructive procedures of the airway in the year 2009 was carried out. We exclude those treated endoscopically and those who had vascular rings. The positive pressure mechanism used in the Surgery Critical Care Unit was a design made by the unit based on the circuit devised by Mapleson that provides optimum levels of ventilation without need for connection to a respiratory. We analyze the results, postoperatory intubation time, time dependent on NIPPV and medical treatment received. RESULTS: A total of 7 patients (1 Female and 6 Males) with median age of 1.6 (0.1-7.5) years were included. The diagnoses were: 4 subglottic stenosis, 2 had tracheal stenosis and 1 subcarinal stenosis with involvement of both principal bronchioles. The techniques used were: laryngotracheoplasty with costal cartilage graft (4), tracheoplasty with costal cartilage (1) and sliding tracheoplasty (2) with bilateral bronchoplasty in one of them. The mean time of nasotracheal intubation was 3 days, and mean time of NIPPV was 2.3. No patient required reintubation and none had infectious complications. CONCLUSIONS: Ventilatory support by VPPNI allows effective extubation in these patients, it being possible to maintain a safe airway. Infectious complications, frequent in prolonged intubations, were not observed in any of the cases.

Aspectos morfológicos de biópsias musculares em equinos com miopatia sob forma de surto / Morphological features of muscle biopsies from horses of a myopathy outbreak

As miopatias em equinos são classificadas de acordo com aspectos clínicos, morfológicos e moleculares, em três grandes grupos: não associadas ao exercício, associadas ao exercício e devido alteração da condução elétrica do sarcolema. Apesar dos avanços no diagnóstico, a literatura ainda relata surtos de miopatia em equinos sem etiologia esclarecida em diversos países. O objetivo desse estudo foi descrever as alterações histológicas e histoquímicas de biópsias musculares de equinos acometidos por miopatia. Sete equinos da raça Quarto de Milha, com 18-24 meses de idade, apresentaram sinais clínicos de miopatia. Dentre esses animais, cinco apresentaram sinais subagudos leves a moderados e dois apresentaram sinais hiperagudos severos e decúbito lateral. Foram realizadas biópsias musculares utilizando a técnica percutânea, por agulha tipo Bergström, no músculo glúteo médio em todos os animais acometidos. As amostras foram processadas por meio de técnicas histológicas (HE, Tricrômio de Gomori modificado) e histoquímicas (PAS, NADH, ATPase). Nos quadros clínicos mais leves, a principal alteração encontrada foi a presença de fibras vermelhas rajadas do tipo I e IIA, que estão associadas às alterações do metabolismo oxidativo e das funções mitocondriais, como ocorrem nas miopatias mitocondriais. Também foram observadas fibras atróficas do tipo I e IIA, além da presença de agregados subsarcolemais. Nos quadros mais severos o tecido muscular apresentou infiltrado inflamatório, aumento de colágeno, fagocitose, necrose, calcificação e regeneração muscular. Diante dos achados morfológicos, da resposta à terapia com vitamina E e Se e da baixa mortalidade quando comparado aos relatos de miopatia atípica, conclui-se que esse surto foi desencadeado por lesões mitocondriais, caracterizadas pelas fibras musculares vermelhas rajadas, possivelmente devido uma quebra da homeostase de vitamina E e Se, sendo compatível com o diagnóstico de miopatia nutricional.

Equine myopathies are classified according clinic, morphologic and molecular features in three groups: Non-exertional, exertional, and abnormal muscle membrane conduction. In spite the advances in diagnostic, the literature has reported outbreaks of equine myopathy without clear etiology in several countries. The aim of this study was to describe the histological and histochemical findings of muscle biopsies in an outbreak of equine myopathy. Seven 18 to 24-month-old Quarter horses showed clinical signs of myopathy. Five horses presented mild clinical signs and two horses had severe clinical signs with recumbency. Muscle biopsies were obtained from gluteal medium muscle by percutaneous technique with Bergstrom needle in all affected horses. Muscle samples were processed by histological (HE, modified gomori-trichrome) and histochemical (PAS, NADH, ATPase) technics. In animals with mild clinical signs, ragged red fibers type I and IIA, related to the oxidative metabolism dysfunction of mitochondria, was the main abnormality found. Muscle fiber atrophy and presence of subsarcolemmal aggregates in type I and IIA muscle fibers were also observed. More severe affected horses presented inflammatory infiltrate, proliferation of collagen, phagocytosis, necrosis and calcification. Based on the morphological findings, vitamin E therapy response associated with the low mortality when compared with atypical myopathy reports, We concluded that this outbreak was triggering for mitochondrial lesions, characterized by ragged red muscle fibers, probably due a breakdown homeostasis in vitamin E and Se, being compatible with nutritional myopathy diagnosis.

Parafollicular C-cells of the thyroid are decreased in patients with congenital diaphragmatic hernia.

BACKGROUND: Parathyroid and thymic anomalies related to embryonic neural crest dysfunction have been demonstrated in rats with congenital diaphragmatic hernia (CDH). These rats, like infants with CDH, have conotruncal, facial, and other neurocristal defects. The present study examines whether parafollicular C-cells (CC) of the thyroid, whose embryogenesis is related to that of the parathyroids and thymus, might also be abnormal in babies with CDH. MATERIAL AND METHODS: Autopsy sections of the thyroids of 12 babies dead from CDH and of 11 controls were stained with anti-calcitonin antibodies. Calcitonin-stained areas and the histological distribution of CC within the thyroid gland were assessed. Mann-Whitney tests were used for comparison, with p<0.05 considered significant. RESULTS: The proportion of stained surface to total thyroid surface was significantly smaller in CDH babies than in controls (0.035±0.030% vs. 0.072±0.052%, p<0.05). A normal central CC location was demonstrated in both groups. CONCLUSIONS: Parafollicular thyroid C-cells are deficient in patients with CDH. These findings further support the involvement of neural crest dysregulation in the pathogenesis of CDH and the pertinence of using this experimental model to investigate the human condition. The clinical effects of this anomaly are unknown and probably irrelevant, but they are currently under scrutiny.