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1.
Int J Mol Sci ; 22(13)2021 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-34199089

RESUMO

The meniscus possesses low self-healing properties. A perfect regenerative technique for this tissue has not yet been developed. This work aims to evaluate the role of hypoxia in meniscal development in vitro. Menisci from neonatal pigs (day 0) were harvested and cultured under two different atmospheric conditions: hypoxia (1% O2) and normoxia (21% O2) for up to 14 days. Samples were analysed at 0, 7 and 14 days by histochemical (Safranin-O staining), immunofluorescence and RT-PCR (in both methods for SOX-9, HIF-1α, collagen I and II), and biochemical (DNA, GAGs, DNA/GAGs ratio) techniques to record any possible differences in the maturation of meniscal cells. Safranin-O staining showed increments in matrix deposition and round-shape "fibro-chondrocytic" cells in hypoxia-cultured menisci compared with controls under normal atmospheric conditions. The same maturation shifting was observed by immunofluorescence and RT-PCR analysis: SOX-9 and collagen II increased from day zero up to 14 days under a hypoxic environment. An increment of DNA/GAGs ratio typical of mature meniscal tissue (characterized by fewer cells and more GAGs) was observed by biochemical analysis. This study shows that hypoxia can be considered as a booster to achieve meniscal cell maturation, and opens new opportunities in the field of meniscus tissue engineering.


Assuntos
Diferenciação Celular , Hipóxia/metabolismo , Menisco/citologia , Menisco/metabolismo , Animais , Biomarcadores , Células Cultivadas , Condrócitos/metabolismo , Expressão Gênica , Glicosaminoglicanos/metabolismo , Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imuno-Histoquímica , Suínos , Engenharia Tecidual/métodos
2.
Res Vet Sci ; 135: 184-191, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33545535

RESUMO

Quadriceps contracture (QC) is reported in dogs mainly as a complication of trauma or parasitic infection. QC causes progressive hind limb deviation, muscular hypotrophy and degenerative joint disease and, in puppies, bone hypoplasia. The aim of this clinical case series is to describe the radiographic and computed tomographic (CT) changes in hind limb ossification centres in thirteen 55 to 57-days-old Doberman Pinscher related littermates induced by QC after repeated intramuscular injections. The presence, size, and shape of ossification centres of affected and unaffected hind limbs were compared. Affected limbs were hyperextended and externally rotated, with genu recurvatum and proximo-medial patellar luxation. QC had no influence on the time of appearance of ossification centres however, it was associated with femoral head flattening, hip subluxation, flattening of the femoral distal epiphysis. The tibial plateau was tilted caudoproximally-craniodistally and wedged into the growth plate. Thirty-two out of fifty-five ossification centres (including diaphyseal and epiphyseal centres, such as femoral head and tibial plateau) were significantly smaller in affected limbs (p < 0.05). Lack of weight-bearing could account for the smaller size of ossification centres in affected tarsi and metatarsi. Progressive limb hyperextension and external rotation might have induced gradual loading withdrawal on the medial aspect of the foot justifying the reduced size observed only for the medial ossification centres of the digits of affected limbs. To the best of our knowledge, this is the first study describing CT findings of hind limb ossification centre changes in puppies with QC contracture.


Assuntos
Contratura/patologia , Doenças do Cão/patologia , Membro Posterior/patologia , Músculo Esquelético/patologia , Doenças Musculares/veterinária , Osteogênese , Animais , Contratura/veterinária , Cães , Artropatias/veterinária , Masculino , Doenças Musculares/patologia , Luxação Patelar/veterinária , Tomografia Computadorizada por Raios X/veterinária
3.
Biomedicines ; 8(12)2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33302345

RESUMO

Substantial epidemiological evidence indicates that a diet rich in polyphenols protects against developing type 2 diabetes. The phenylethanoid glycoside verbascoside/acteoside, a widespread polyphenolic plant compound, has several biological properties including strong antioxidant, anti-inflammatory and neuroprotective activities. The aim of this research was to test the possible effects of verbascoside on pancreatic ß-cells, a target never tested before. Mouse and human ß-cells were incubated with verbascoside (0.8-16 µM) for up to five days and a combination of biochemical and imaging techniques were used to assess the ß-cell survival and function under normal or endoplasmic reticulum (ER)-stress inducing conditions. We found a dose-dependent protective effect of verbascoside against oxidative stress in clonal and human ß-cells. Mechanistic studies revealed that the polyphenol protects ß-cells against ER-stress mediated dysfunctions, modulating the activation of the protein kinase RNA-like endoplasmic reticulum kinase (PERK) branch of the unfolded protein response and promoting mitochondrial dynamics. As a result, increased viability, mitochondrial function and insulin content were detected in these cells. These studies provide the evidence that verbascoside boosts the ability of ß-cells to cope with ER-stress, an important contributor of ß-cell dysfunction and failure in diabetic conditions and support the therapeutic potential of verbascoside in diabetes.

4.
Animals (Basel) ; 10(8)2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32731504

RESUMO

In the present study, a multidisciplinary approach was used in order to evaluate growth, muscle development, and stress status in Siberian sturgeon Acipenser baerii larvae at schooling (T1) and complete yolk sac absorption (T2), reared at three stocking densities (low, medium, and high). Larvae growth, morphological muscle development, and whole-body cortisol levels were assessed. The expression of genes involved in the growth process (igf1 and igf2), in the myogenesis (myog), and in the regulation of cellular stress (glut1, glut2, glut4, and hsp70) was analyzed using a quantitative PCR. Larvae reared at lower densities showed a higher Specific Growth Rate and showed a physiological muscle development. Cortisol levels were low and did not differ significantly, both in different time sampling and across densities, suggesting that either the considered densities are not stressors in this species in the early stages of development or the hypothalamus-pituitary-adrenal (HPA) axis is not yet fully mature. Gene expression of glut1, igf1, and igf2 showed an up-regulation in both developmental stages at all the rearing densities considered, while myog significantly up-regulated at T1 at the highest density. Considering all of the results, it would seem that lower densities should be used in these stages of development, as these showed a higher growth rate, even if it is not economically feasible in commercial hatcheries. Therefore, choosing an intermediate stocking density could be a good compromise between larval performance and economical feasibility.

5.
Theriogenology ; 156: 59-69, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679457

RESUMO

The aryl hydrocarbon receptor (AhR) has been extensively characterized as an environmental sensor with major roles in xenobiotic-induced toxicity. Evidence is accumulating that these functions serve as adaptive mechanisms overlapping its physiological roles. We previously described a critical role of constitutive AhR activation for the correct progress of mammalian oocyte maturation but the signaling pathway through which AhR controls maturation remains unclear. The aim of this study was to investigate whether the AhR interacts with the epidermal growth factor receptor (EGFR) and p42/44 extracellular regulated kinases (ERK1/2), both key factors in the signaling network that finely regulates the oocyte maturation. As experimental model we used bovine cumulus-oocyte complexes (COCs) during in vitro maturation (IVM). Blocking ERK1/2 signaling in COCs during IVM with the specific EGFR inhibitor AG1478 or the mitogen-activated protein kinase kinase (MEK) inhibitor PD98059 downregulated the expression of the AhR-target gene Cyp1a1. Inhibition of AhR activity was associated with a reduction in the oocytes' ability to progress in meiosis resumption. In contrast, exposure to the AhR antagonist resveratrol reduced both CYP1A1 expression and the oocytes' maturation competence, without affecting ERK1/2 signaling. These findings strongly indicate the EGFR/ERKs signaling network as an upstream regulator of the AhR activation in COCs, offering a new understanding of the finely tuned physiological mechanism leading to oocyte maturation. This information may provide fresh opportunities for improving oocyte in vitro maturation, and therefore boosting the efficiency of assisted reproduction techniques in mammals.


Assuntos
Sistema de Sinalização das MAP Quinases , Receptores de Hidrocarboneto Arílico , Animais , Bovinos , Células do Cúmulo/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Técnicas de Maturação in Vitro de Oócitos/veterinária , Oócitos/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais
6.
J Fish Biol ; 96(4): 913-924, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32043574

RESUMO

Environmental temperature is one of the critical factors affecting fish development. The aim of this study was to examine the impact of three different rearing temperatures (16, 19 and 22°C) throughout the endogenous feeding phase of the Siberian sturgeon Acipenser baerii. This was performed by assessing (a) larval survival and growth; (b) immunofluorescence localization and expression of genes involved in muscle development and growth - myog and Igf1; and (c) stress status through the expression of thermal stress genes - Hsp70, Hsp90α and Hsp90ß - and whole body cortisol. Overall survival rate and larval weight did not differ significantly across temperatures. Larvae subjected to 22°C showed faster absorption of the yolk-sac than larvae subjected to 19 or 16°C. Both at schooling and at the end of the trial, larvae reared at 16°C showed significantly lower levels of cortisol than those reared at 19 or 22°C. IGF-1 immunopositivity was particularly evident in red muscle at schooling stage in all temperatures. The expression of all Hsps as well as the myog and Igf1 genes was statistically higher in larvae reared at 16°C but limited to the schooling stage. Cortisol levels were higher in larvae at 22°C, probably because of the higher metabolism demand rather than a stress response. The observed apparent incongruity between Hsps gene expression and cortisol levels could be due to the lack of a mature system. Further studies are necessary, especially regarding the exogenous feeding phase, in order to better understand if this species is actually sensitive to thermal stress.


Assuntos
Meio Ambiente , Peixes/crescimento & desenvolvimento , Estresse Fisiológico/fisiologia , Temperatura , Animais , Hidrocortisona/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Desenvolvimento Muscular/fisiologia
7.
Cells ; 9(2)2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31973209

RESUMO

Joint motion and postnatal stress of weight bearing are the principal factors that determine the phenotypical and architectural changes that characterize the maturation process of the meniscus. In this study, the effect of compressive forces on the meniscus will be evaluated in a litter of 12 Dobermann Pinschers, of approximately 2 months of age, euthanized as affected by the quadriceps contracture muscle syndrome of a single limb focusing on extracellular matrix remodeling and cell-extracellular matrix interaction (i.e., meniscal cells maturation, collagen fibers typology and arrangement). The affected limbs were considered as models of continuous compression while the physiologic loaded limbs were considered as controls. The results of this study suggest that a compressive continuous force, applied to the native meniscal cells, triggers an early maturation of the cellular phenotype, at the expense of the proper organization of collagen fibers. Nevertheless, an application of a compressive force could be useful in the engineering process of meniscal tissue in order to induce a faster achievement of the mature cellular phenotype and, consequently, the earlier production of the fundamental extracellular matrix (ECM), in order to improve cellular viability and adhesion of the cells within a hypothetical synthetic scaffold.


Assuntos
Força Compressiva/fisiologia , Matriz Extracelular/fisiologia , Menisco/fisiologia , Animais , Fenômenos Biomecânicos , DNA/metabolismo , Cães , Módulo de Elasticidade , Glicosaminoglicanos/metabolismo , Imageamento por Ressonância Magnética , Menisco/diagnóstico por imagem
8.
Animals (Basel) ; 9(12)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795348

RESUMO

Weaning is very stressful for piglets and leads to alterations in the intestinal barrier, a reduction in nutrient absorption and a higher susceptibility to intestinal diseases with heavy economic losses. This review describes the structures involved in the intestinal barrier: the epithelial barrier, immune barrier and the enteric nervous system. Here, new insights into the interactions between feed components and the physiology and morphology of the epithelial barrier are highlighted. Dietary strategies focused on improving gut health are also described including amino acids, phytochemicals and organic acids.

9.
Animals (Basel) ; 9(12)2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31842324

RESUMO

Seaweeds are macroalgae, with different sizes, colors and composition. They consist of brown algae, red algae and green algae, which all have a different chemical composition and bioactive molecule content. The polysaccharides, laminarin and fucoidan are commonly present in brown seaweeds, ulvans are found in green seaweeds and, red algae contain a large amount of carrageenans. These bioactive compounds may have several positive effects on health in livestock. In order to reduce the antimicrobials used in livestock, research has recently focused on finding natural and sustainable molecules that boost animal performance and health. The present study thus summarizes research on the dietary integration of seaweeds in swine. In particular the influence on growth performance, nutrients digestibility, prebiotic, antioxidant, anti-inflammatory, and immunomodulatory activities were considered. The review highlights that brown seaweeds seem to be a promising dietary intervention in pigs in order to boost the immune system, antioxidant status and gut health. Data on the use of green seaweeds as a dietary supplementation seems to be lacking at present and merit further investigation.

10.
Animals (Basel) ; 9(1)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30634572

RESUMO

Reducing oxidative stress is an important goal in post-weaning piglets; previous studies have reported that verbascoside decreases oxidative stress in piglets. The effect of verbascoside on gut morphology and α-transducin and α-gustducin expression in weaned piglets fed high dosages of sunflower oil, inducing oxidative stress, was evaluated. A diet with 9% sunflower oil (T1), the same diet supplemented with 5 mg of verbascoside/kg feed (T2) and a diet containing starch (control-CTR) were employed. Histology, histometry, histochemistry, immunofluorescence and Western blot analyses were performed on the piglets' small intestine. In the T1 group, apical erosion was observed and villi height was lower than in other groups. The mucin profile was acidic in goblet cells of both the T1 and T2 groups. However, it was both neutral and acidic in the CTR group. Dietary treatments did not affect α-gustducin expression. Otherwise, the expression of α-transducin in the duodenum was lower (p < 0.01) in the T1 groups than in the other groups. The colocalization of α-transducin with chromogranin A and ghrelin revealed that the endocrine cells were immunopositive for both ghrelin and α-transducin. Overall, these results provide new insights into gut sensory perception in piglets and contribute to understanding how feed ingredients such as fat and polyphenols may be involved in gustatory signal transduction.

11.
Tissue Eng Part A ; 25(13-14): 978-989, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30398398

RESUMO

IMPACT STATEMENT: The importance of the present study is linked to how the contact forces act on the knee meniscus in particular, considering the femoral condyles and tibial plateau: this can be useful as a base for the ultimate creation of tissue-engineered biphasic scaffolds, which can mimic the native tissue complex, for meniscal repair or regeneration.


Assuntos
Fêmur/fisiologia , Meniscos Tibiais/fisiologia , Tíbia/fisiologia , Animais , Fenômenos Biomecânicos , Colágeno Tipo I/metabolismo , DNA/metabolismo , Feminino , Fêmur/diagnóstico por imagem , Glicosaminoglicanos/metabolismo , Meniscos Tibiais/diagnóstico por imagem , Suínos , Tíbia/diagnóstico por imagem , Tomografia Computadorizada por Raios X
12.
Int J Artif Organs ; 41(7): 400-412, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29781355

RESUMO

INTRODUCTION: An innovative approach to the treatment of tendon injury or degeneration is given by engineered grafts, made available through the development of bioreactors that generate tendon tissue in vitro, by replicating in vivo conditions. This work aims at the design of a bioreactor capable of applying a stimulation of cyclic strain on cell constructs to promote the production of bioartificial tissue with mechanical and biochemical properties resembling those of the native tissue. METHODS: The system was actuated by an electromagnet and design specifications were imposed as follows. The stimulation protocol provides to scaffolds a 3% preload, a 10% deformation, and a stimulation frequency rate set at 0.5, 1, and 2 Hz, which alternates stimulation/resting phases. Porcine tenocytes were seeded on collagen scaffolds and cultured in static or dynamic conditions for 7 and 14 days. RESULTS: The culture medium temperature did not exceed 37°C during prolonged culture experiments. The applied force oscillates between 1.5 and 4.5 N. The cyclic stimulation of the engineered constructs let both the cells and the scaffold fibers align along the strain direction in response to the mechanical stimulus. CONCLUSION: We designed a pulsatile strain bioreactor for tendon tissue engineering. The in vitro characterization shows a preferential cell alignment at short time points. Prolonged culture time, however, seems to influence negatively on the survival of the cells indicating the need of further optimization concerning the culture conditions and the mechanical stimulation.


Assuntos
Estresse Mecânico , Tendões/citologia , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Reatores Biológicos , Células Cultivadas , Colágeno , Suínos
13.
Anim Sci J ; 89(3): 616-624, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29231279

RESUMO

The objective of this study was to evaluate dietary supplementation with different copper sulphate (CuSO4 ) forms on small intestine microanatomy and large intestine microbiota. Ninety weaned piglets were divided into three experimental groups: control diet (CTR), with no added CuSO4 and diets supplemented with 150 ppm of CuSO4 in protected (150P) and unprotected form (150UP). After 18 days of dietary treatment, six piglets per treatment were randomly selected and sacrificed. Duodenum villi length and crypt depths were higher (P < 0.001) in the animals fed 150UP than other groups. Glial fibrillary acidic protein (GFAP), a marker for enteric glial cells, was unaffected by dietary treatments. The total bacteria and Enterobacteriaceae bacteria counts were lower (P < 0.05) in cecum of animals fed 150P in comparison with the other two groups. In the colon the Streptococci spp were lower (P < 0.001) in both CuSO4 supplemented groups than controls. The obtained results revealed a modulation of intestinal structure and microbiota exerted by the studied CuSO4 dietary supplementation. The present data show that dietary supplementation with 150UP in the first period post-weaning may assist in restoring the gut morphology, improving duodenal structure.


Assuntos
Carga Bacteriana , Sulfato de Cobre/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais , Enterobacteriaceae , Intestino Grosso/microbiologia , Intestino Delgado/anatomia & histologia , Streptococcus , Suínos/anatomia & histologia , Suínos/microbiologia , Animais , Duodeno/anatomia & histologia , Feminino , Fatores de Tempo , Desmame
14.
J Cell Mol Med ; 21(11): 3066-3075, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28580627

RESUMO

An in-depth knowledge of the native meniscus morphology and biomechanics in its different areas is essential to develop an engineered tissue. Meniscus is characterized by a great regional variation in extracellular matrix components and in vascularization. Then, the aim of this work was to characterize the expression of factors involved in angiogenesis in different areas during meniscus maturation in pigs. The menisci were removed from the knee joints of neonatal, young and adult pigs, and they were divided into the inner, intermediate and outer areas. Vascular characterization and meniscal maturation were evaluated by immunohistochemistry and Western blot analysis. In particular, expression of the angiogenic factor Vascular Endothelial Growth Factor (VEGF) and the anti-angiogenic marker Endostatin (ENDO) was analysed, as well as the vascular endothelial cadherin (Ve-CAD). In addition, expression of Collagen II (COLL II) and SOX9 was examined, as markers of the fibro-cartilaginous differentiation. Expression of VEGF and Ve-CAD had a similar pattern in all animals, with a significant increase from the inner to the outer part of the meniscus. Pooling the zones, expression of both proteins was significantly higher in the neonatal meniscus than in young and adult menisci. Conversely, the young meniscus revealed a significantly higher expression of ENDO compared to the neonatal and adult ones. Analysis of tissue maturation markers showed an increase in COLL II and a decrease in SOX9 expression with age. These preliminary data highlight some of the changes that occur in the swine meniscus during growth, in particular the ensemble of regulatory factors involved in angiogenesis.


Assuntos
Envelhecimento/metabolismo , Colágeno Tipo II/genética , Meniscos Tibiais/metabolismo , Neovascularização Fisiológica/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fatores Etários , Envelhecimento/genética , Animais , Animais Recém-Nascidos , Antígenos CD/genética , Antígenos CD/metabolismo , Caderinas/genética , Caderinas/metabolismo , Condrócitos/citologia , Condrócitos/metabolismo , Colágeno Tipo II/metabolismo , Endostatinas/genética , Endostatinas/metabolismo , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Articulações/citologia , Articulações/crescimento & desenvolvimento , Articulações/metabolismo , Meniscos Tibiais/irrigação sanguínea , Meniscos Tibiais/citologia , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Suínos , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
Neuroscience ; 354: 208-220, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28456717

RESUMO

Tauopathies are a class of neurodegenerative diseases associated with the pathological aggregation of tau protein in the human brain. Although numerous studies in mouse models of Alzheimer disease (AD) have shown a correlation among diet, beta-amyloid and AD onset, little is known about the impact of diet on Tau. We investigated whether a low fat-protein diet (LFPD) may improve lifespan, cognitive and locomotor activity in P301L-tg mouse model of tauopathy. Our data indicate that LFPD has a beneficial effect on these parameters. Tg mice fed with standard diet shown a decrease in body weight, food intake and survival rate if compared to wild type animals. In contrast, LFPD counteracted weight loss, increased mortality and ameliorated cognitive and locomotor performances in tg mice. LFPD also reduced the abnormal accumulation of agglomerates of P-Tau (pathological features of tauopathies) and the expression of apoptotic markers (i.e., TUNEL immunopositive neurons) in the prefrontal cerebral cortex and hippocampus of P301L-tg mice. Interestingly, some of these effects are sex-dependent. For instance, tg females, but not males, fed with LFPD had a significant increase of body weight and a reduction of P-Tau agglomerates compared to tg fed with standard diet. These changes correlated with a more pronounced improvement of cognition and locomotor activity in females than in male tg fed with LFPD. Altogether, these results suggest a sex dependent neuroprotective effect of LFPD in P301L-tg mice, suggesting that lifestyle intervention strategies may be clinically relevant for delaying the onset of cognitive impairment and dementia, especially in females.


Assuntos
Dieta com Restrição de Proteínas/métodos , Fármacos Neuroprotetores/uso terapêutico , Tauopatias/dietoterapia , Análise de Variância , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/genética , Encéfalo/patologia , Modelos Animais de Doenças , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/genética , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Feminino , Marcação In Situ das Extremidades Cortadas , Locomoção/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Reconhecimento Psicológico/efeitos dos fármacos , Reconhecimento Psicológico/fisiologia , Tauopatias/patologia , Proteínas tau/genética
16.
J Alzheimers Dis ; 56(4): 1279-1292, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28157099

RESUMO

P301L transgenic (tg) mice well mimic features of human tauopathies and provide a good model for investigating the role of tau in neurodegenerative events. We here analyzed the possible interactions among phosphorylation of tau (p-tau), spine injury, neuronal death, and sex in the P301L mouse model of tauopathy. When compared to control mice (ctr), P301L transgenic mice (tg) presented a lower body weight, reduced survival rate, hyperphosphorylated tau, spine injury, and neuronal loss in both cerebral cortex and hippocampus at 15 months of age. Importantly, we found that pathological features were more pronounced in female than male tg mice. Recent reports underline that tau may be localized within both pre- and post-synaptic compartments, suggesting that it may possibly induce or contribute to synaptic dysfunction. Therefore, we focused our attention on tau localization at dendritic spines. We detected high levels of both tau and p-tau in dendritic spine of P301L transgenic mice. In addition, p-tau correlated with a significant reduction of post-synaptic markers, such as GluN2A, GluN2B, GluA1, GluA2, Drebrin, and PSD-95, in P301L mice. The p-tau levels are higher in female than in male mice, and the increased p-tau was consistent with a proportional decrease in the post-synaptic marker levels analyzed. The P301L-tg females showed a more severe synaptopathy compared to males. Future investigations on the postsynaptic role of p-tau will be necessary to understand its toxic effects and provide insights into new therapeutic targets for maintaining spine integrity, highlighting the importance of tau toxicity as well as the impact of sex on tau-pathology.


Assuntos
Córtex Cerebral/metabolismo , Espinhas Dendríticas/metabolismo , Hipocampo/metabolismo , Caracteres Sexuais , Tauopatias/metabolismo , Proteínas tau/metabolismo , Animais , Apoptose/fisiologia , Córtex Cerebral/patologia , Espinhas Dendríticas/patologia , Modelos Animais de Doenças , Feminino , Hipocampo/patologia , Humanos , Masculino , Camundongos Transgênicos , Neurônios/metabolismo , Neurônios/patologia , Análise de Sobrevida , Tauopatias/patologia
17.
Eur J Histochem ; 61(4): 2850, 2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-29313594

RESUMO

The present study aims at investigating muscle development and stress response in early stages of Siberian sturgeon when subjected to different rearing temperatures, by analysing growth and development of the muscle and by assessing the stress response of yolk-sac larvae. Siberian sturgeon larvae were reared at 16°C, 19°C and 22°C until the yolk-sac was completely absorbed. Sampling timepoints were: hatching, schooling and complete yolk-sac absorption stage. Histometrical, histochemical and immunohistochemical analyses were performed in order to characterize muscle growth (total muscle area, TMA; slow muscle area, SMA; fast muscle area, FMA), development (anti-proliferating cell nuclear antigen -PCNA or anticaspase) as well as stress conditions by specific stress biomarkers (heat shock protein 70 or 90, HSP70 or HSP90). Larvae subjected to the highest water temperature showed a faster yolk-sac absorption. Histometry revealed that both TMA and FMA were larger in the schooling stage at 19°C while no differences were observed in the SMA at any of the tested rearing temperatures. PCNA quantification revealed a significantly higher number of proliferating cells in the yolk-sac absorption phase at 22°C than at 16°C. HSP90 immunopositivity seems to be particularly evident at 19°C. HPS70 immunopositivity was never observed in the developing lateral muscle.


Assuntos
Desenvolvimento Muscular/fisiologia , Estresse Fisiológico/fisiologia , Temperatura , Animais , Proliferação de Células , Peixes/crescimento & desenvolvimento , Imuno-Histoquímica , Músculos/citologia
18.
PLoS One ; 11(8): e0161590, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27548063

RESUMO

Tendinopathy is a big burden in clinics and it represents 45% of musculoskeletal lesions. Despite the relevant social impact, both pathogenesis and development of the tendinopathy are still under-investigated, thus limiting the therapeutic advancement in this field. The purpose of this study was to evaluate the dose-dependent and time-related tissue-level changes occurring in a collagenase-induced tendinopathy in rat Achilles tendons, in order to establish a standardized model for future pre-clinical studies. With this purpose, 40 Sprague Dawley rats were randomly divided into two groups, treated by injecting collagenase type I within the Achilles tendon at 1 mg/mL (low dose) or 3 mg/mL (high dose). Tendon explants were histologically evaluated at 3, 7, 15, 30 and 45 days. Our results revealed that both the collagenase doses induced a disorganization of collagen fibers and increased the number of rounded resident cells. In particular, the high dose treatment determined a greater neovascularization and fatty degeneration with respect to the lower dose. These changes were found to be time-dependent and to resemble the features of human tendinopathy. Indeed, in our series, the acute phase occurred from day 3 to day 15, and then progressed towards the proliferative phase from day 30 to day 45 displaying a degenerative appearance associated with a very precocious and mild remodeling process. The model represents a good balance between similarity with histological features of human tendinopathy and feasibility, in terms of tendon size to create lesions and costs when compared to other animal models. Moreover, this model could contribute to improve the knowledge in this field, and it could be useful to properly design further pre-clinical studies to test innovative treatments for tendinopathy.


Assuntos
Tendão do Calcâneo/efeitos dos fármacos , Colagenases/administração & dosagem , Neovascularização Patológica/diagnóstico , Tendinopatia/diagnóstico , Tendão do Calcâneo/metabolismo , Tendão do Calcâneo/patologia , Animais , Colágeno/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Relação Dose-Resposta a Droga , Humanos , Injeções , Masculino , Neovascularização Patológica/induzido quimicamente , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Ratos , Ratos Sprague-Dawley , Tendinopatia/induzido quimicamente , Tendinopatia/metabolismo , Tendinopatia/patologia , Fatores de Tempo , Cicatrização/fisiologia
19.
J Craniofac Surg ; 27(3): 702-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27046471

RESUMO

PURPOSE: Maxillary sinus floor elevation procedure has the objective of augmenting available bone in atrophic posterior maxilla to allow dental implants placement. The main aim of this prospective study was to evaluate clinically and histomorphometrically the performance of biphasic calcium phosphate (BCP) used in conjunction with platelet-rich plasma (PRP) compared with demineralized bovine bone matrix (DBBM) and PRP in sinus floor elevation surgery. MATERIALS AND METHODS: Patients candidate to sinus floor elevation were treated using either BCP and PRP or DBBM and PRP. Biopsies were retrieved using trephine bur during implant placement surgery 6 months after grafting. Clinical success of implants was evaluated 1 year after prosthesis delivery. Histomorphometric analysis was performed assessing the relative volume of newly formed bone. RESULTS: A total of 20 patients were recruited, and 20 sinus augmentation procedures were performed, 10 for each group. A total of 42 implants were placed. One year after prosthetic loading a 100% implant survival rate was reported in both groups. Histomorphometric analysis revealed that the mean amount of new bone formation was 18.6 ±â€Š3.3% in BCP group and it was 21.9 ±â€Š4.9% in DBBM group, without statistically significant difference. In BCP group a greater amount of collagen type I was found with respect to DBBM group. CONCLUSIONS: Both grafting materials led to an excellent performance regarding implant survival rate after 1 year follow-up, without any significant adverse sequelae. A similar capability of inducing new bone formation was observed in both groups, even though the higher quantity of collagen type I in BCP group may suggest a greater potential for bone formation over time as compared with DBBM.


Assuntos
Matriz Óssea/transplante , Implantação Dentária Endo-Óssea/métodos , Hidroxiapatitas/farmacologia , Maxila/cirurgia , Plasma Rico em Plaquetas , Levantamento do Assoalho do Seio Maxilar/métodos , Idoso , Animais , Materiais Biocompatíveis , Substitutos Ósseos , Bovinos , Cerâmica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteogênese , Estudos Prospectivos
20.
Am J Phys Anthropol ; 158(4): 636-45, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26265488

RESUMO

OBJECTIVES: The variation and persistence of blood components, in particular red blood cells (RBCs), within bone tissue during the decomposition process, especially at the early stages and in different taphonomic conditions, has never been thoroughly investigated, regardless of the fact that knowing how blood survives or degrades within bone could be of help in solving many anthropological issues, such as trauma analysis and interpretation. MATERIALS AND METHODS: This research investigated the influence of time and taphonomy on the persistence and detectability of blood components in parietal bone fragments (of different post mortem periods and taphonomic conditions) through histological (Hematoxilin and Eosin, HE) and immunohistochemical (Glycophorin A, GYPA) analyses. RESULTS: The immunohistochemical investigation for GYPA showed the presence of RBCs under the form of erythrocyte debris or residues otherwise morphologically unidentifiable using only HE staining. Hence, while well-defined RBCs can be observed only in the first week of decomposition, afterward these structures can be detectable with certainty only by immunohistochemical analysis, which reveals discrete quantities of RBC residues also in dry bone (post mortem interval, or PMI, of 15 years), but not in archaeological samples, in which the greater PMI and the different taphonomic conditions together could be the answer behind such difference. DISCUSSION: This study highlights the usefulness and potential of immunohistochemical detection of GYPA in RBC investigation and gives a realistic idea of the persistence and detectability of erythrocytes in different osteological taphonomic conditions, in contrast to results reported by some authors in literature. Another important result concerns the detection of RBC residues in dry bone, which opens the way to the possible use of RBCs in trauma interpretation.


Assuntos
Osso e Ossos/química , Eritrócitos/química , Antropologia Forense , Fósseis , Morte , Glicoforinas , Humanos
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