Morphofunctional characteristics of skeletal muscle in rats with cerebral palsy.

Knowledge of skeletal muscle adaptations is important to understand the functional deficits in cerebral palsy (CP). This study aimed to investigate the morphofunctional characteristics of skeletal muscle in a CP animal model. Initially, pregnant Wistar rats were injected intraperitoneally with saline or lipopolysaccharide over the last five days of pregnancy. The control group (n = 8) consisted of male pups born to females injected with saline. The CP group (n = 8) consisted of male pups born to females injected with lipopolysaccharide, which were submitted to perinatal anoxia [day of birth, postnatal day 0 (P0)] and sensorimotor restriction (P1-P30). The open-field test was undertaken on P29 and P45. On P48, the animals were weighed, and the plantaris muscle was collected and its weight and length were measured. Transverse sections were stained with haematoxylin-eosin, NADH-TR, Masson's trichrome and non-specific esterase reaction for analysis. and transmission electron microscopy was performed. In the CP group, reductions were observed in mobility time, number of crossings and rearing frequency, body weight, muscle weight and length, and nucleus-to-fibre and capillary-to-fibre ratios. There was a statistically significant increase in the percentage area of the muscle section occupied by collagen; reduction in the area and increase in the number of type I muscle fibres; increase in myofibrillar disorganization and Z-line disorganization and dissolution; and reduction in the area and largest and smallest diameters of neuromuscular junctions. Thus this animal model of CP produced morphofunctional alterations in skeletal muscle, that were associated with evidence of motor deficits as demonstrated by the open-field test.

Complete genome sequence of the first non-Asian isolate of Bombyx mori nucleopolyhedrovirus.

Brazil is one of the largest silk producers in the world. The domesticated silkworm (Bombyx mori) was formally introduced into the country in the twentieth century, and the state of Paraná is the main national producer. During larval stages, B. mori can be afflicted by many different infectious diseases, which lead to substantial losses in silk production. In this work, we describe the structure and complete genome sequence of the first non-Asian isolate of Bombyx mori nucleopolyhedrovirus (BmNPV), the most important silkworm pathogen. The BmNPV-Brazilian isolate is a nucleopolyhedrovirus with singly enveloped nucleocapsids within polyhedral occlusion bodies. Its genome has 126,861 bp with a G + C content of 40.4 %. Phylogenetic analysis clustered the virus with the Japanese strain (BmNPV-T3). As expected, we have detected intra-population variability in the virus sample. Variation along homologous regions (HRs) and bro genes was observed; there were seven HRs, deletion of bro-e, and division of bro-a into two ORFs. The study of baculoviruses allows for a better understanding of virus evolution providing insight for biological control of insect pests or protection against the pernicious disease caused by these viruses.

Nociceptive and histomorphometric evaluation of neural mobilization in experimental injury of the median nerve.

The carpal tunnel syndrome is the most common peripheral neuropathy in the upper limb, but its treatment with conservative therapies such as neural mobilization (NM) is still controversial. The aim of this study was to investigate the efficacy of the NM as treatment in a model of median nerve compression. 18 Wistar rats were subjected to compression of the median nerve in the right elbow proximal region. Were randomly divided into G1 (untreated), G2 (NM for 1 minute), and G3 (NM for 3 minutes). For treatment, the animals were anesthetized and the right forelimb received mobilization adapted to humans, on alternated days, from the 3rd to the 13th day postoperatively (PO), totaling six days of therapy. Nociception was assessed by withdrawal threshold, and after euthanasia histomorphometric analysis of the median nerve was performed. The nociceptive evaluation showed in G2 and G3 delay in return to baseline. Histomorphometric analysis showed no significant differences in the variables analyzed. It is concluded that the NM was not effective in reducing nociceptive sensation and did not alter the course of nerve regeneration.

The effects of low-level laser therapy, 670 nm, on epiphyseal growth in rats.

The longitudinal growth of long bones is attributed to epiphyseal growth. However, the effects of low-level laser therapy (LLLT) in such structures has still not been studied extensively in the literature. Therefore, the aim of this study was to evaluate the use of LLLT, 670 nm, at three different doses on the epiphyseal growth of the right tibia of rats. Twenty-one Wistar rats, aged four weeks, were subjected to the application of LLLT, with dosage according to the group (G4: were submitted to the application of 4 J/cm(2); G8: were submitted to the application of 8 J/cm(2); G16: were submitted to the application of 16 J/cm(2)). After completion of protocol they were kept until they were 14 weeks of age and then submitted to a radiological examination (evaluation of limb length) and euthanised. The histological analysis of the growth plates (total thickness and hypertrophic and proliferative zones) was then performed. Comparisons were made with the untreated left tibia. No differences were observed in any of the reviews (radiological and histological), when comparing the right sides (treated) to the left (untreated). It was concluded that the treatment with LLLT within the parameters used caused changes neither in areas of the epiphyseal cartilage nor in the final length of limbs.

Effects of the Association of Periodontitis and Type 1 Diabetes Mellitus Induced on Periodontal Tissues and the Duodenal Mucosa of Wistar Rats.

Forty Wistar rats were used: (1) control group (CG); (2) group of periodontal disease (PD); (3) type 1 diabetes mellitus group (T1DM); (4) type 1 diabetes mellitus + periodontal disease group (T1DM + PD). In groups T1DM and T1DM + PD, T1DM induction was performed with the administration of streptozotocin (STZ) 80 mg/kg intraperitoneal body weight. The PD and T1DM + PD groups were submitted to PD induction with ligation. After the experimental phase and euthanasia, histological, radiographic, and morphological analyses were performed. For data analysis, was used the one-way ANOVA and post-test Tukey. The T1DM + PD group had a significantly higher level of fasting blood glucose compared to the other groups. In radiographic and histomorphometric analyses, the T1DM + PD group showed greater alveolar bone loss compared to the control group. The T1DM + PD group showed greater osteoclastic activity compared to the control, T1DM, and PD groups and exhibited an intense inflammatory infiltrate, most of which were PMN, being that the amount of this group of cells (PMN) was significantly greater than the PD group. The heights of the intestinal villi were statistically higher in the PD, T1DM, T1DM + PD groups, compared to the control. Regarding the height of the crypt, only the T1DM and T1DM + PD groups were significantly higher compared to the other groups. Association of diabetes and periodontal inflammation increased the deleterious effects on bone tissue and adverse effect on the permeability of the duodenal mucosa.

Susceptibility of the Bombyx mori cardia cells to Nucleopolyhedrovirus, multiple subgroup, BmMNPV.

Bombyx mori entomopathogenic virus infection is a serious problem for silk production in tropical regions. Here, we investigate the susceptibility of the B. mori cardia epithelial cells to B. mori Nucleopolyhedrovirus, BmMNPV. Results show that cardia cells are susceptible to BmMNPV and that the cytopathology is similar to that in other target cells. The infection was detected at 6 day post-inoculation. This infection time, together with the protected cover intima, suggests that the cardia region is a secondary target, infected by budded virus.

Negative impact of Novaluron on the nontarget insect Bombyx mori (Lepidoptera: Bombycidae).

Due to increased use of agrochemicals and growing concerns about ecotoxicology, the development of new insecticides, moving away from those with neurotoxic and broad spectrum effects towards insecticides that are safer for the environment and nontarget beneficial species, has been a research priority. Novaluron stands out among these newer insecticides, is an insect growth regulator that is used for the control of insect pests in crops grown close to mulberry plantations. Mulberry serves as food for the silkworm Bombyx mori, which is a nontarget insect of great economic importance to silk production. We investigated the lethal and sublethal effects of Novaluron on the development of B. mori. Larvae were segregated into experimental groups: the control groups (CGs) and the treatment groups (TGs), which were treated with the Novaluron concentration of 0.15 mL/L. Following exposure, we analyzed: larval mortality, changes in the insect life cicle and cytotoxic effects on the midgut cells. This is the first report about the Novaluron's effects on B.mori. We detected rupture in the integument, complete cessation of feeding, late development, incomplete ecdysis and production of defective cocoons. After 240 h of exposure, there was 100% mortality in TG larvae exposed in the 3rd instar and 20% mortality from larvae exposed in the 5th instar. Cytotoxic effects was observed, such as dilation of cells, emission of cytoplasmic protrusions, extreme rarefaction of the cytoplasm and nuclei, dilation of the endoplasmic reticulum in addition to changes in mitochondria, the presence of large digestive vacuoles and intercellular spaces and the presence of active caspase. Novaluron exposure impairs the midgut and may affect the physiological functions of this organ. Novaluron additionally compromises several phases of insect development, indicating the importance of toxicology studies that utilize different life stages of nontarget species to evaluate the safe use of insecticides.

Sericin silk protein in peripheral nervous repair associated with the physical exercise of swimming in Wistar rats.

OBJECTIVE: To verify the action of sericin associated to swim exercise with overload, on sciatic nerve repair in Wistar rats, after 22 days of nerve compression. METHODS: Forty animals been composed of five groups: control, injury, injury-sericin, injury-swimming and injury-sericin-swimming. During the lesion procedure, sericin, in hydrolyzed form, applied directly to the injury in the injury-sericin and injury-sericin-swimming groups. Injury-swimming and injury-sericin-swimming groups underwent to 5 days per week for 3 weeks, with a 10% overload of the animal's body weight, and a weekly progressive evolution of swimming time, lasting 15, 20 and 25 min/day. Pre and throughout the treatment period the animals performed evaluation of sciatic functional index and pressure pain threshold with digital von Frey filament. Euthanasia was performed on the 22nd postoperative day, and two fragments of the nerve were collected and prepared for descriptive and quantitative analysis. RESULTS: The sciatic functional index assessment showed significant differences in the motor function of the control until the 14th day. Regarding the allodynia, there was revealed a significant improvement in injury-swimming performance relative to injury, injury-sericin and injury-sericin-swimming, and the number of viable and non-viable nerve fibers smaller than 4 µm in diameter was significantly higher in the injury-sericin-swimming. CONCLUSION: swimming showed a better evolution of the nociceptive threshold and allodynia. Sericin treatment had exacerbated pro-inflammatory characteristics. On the other hand, the association of sericine and swimming showed a possible regulatory effect by resting swimming exercise, with a significant increase of fibers of smaller diameter.

Antioxidant Systems as a Response to Midgut Cellular of Bombyx mori Lineu, 1758 (Lepidoptera: Bombycidae) Infection for Baculoviruses.

Bombyx mori nucleopolyhedrovirus (BmNPV) is a DNA virus that infects different tissues in Bombyx mori at immature stage. Caterpillars become infected after ingesting polyhedral occlusion bodies (POB) present in contaminated mulberry leaves and spread through the body after passing the epithelium of the midgut. As this organ is responsible for digestion, most absorption of nutrients requires an intact epithelium to maintain gastrointestinal physiology. Considering the importance of this organ in the feeding of caterpillars and in the production of quality silk threads, and because it is also the first barrier faced by the BmNPV, the study analyzed details of cytopathological events in the intestinal cells as well as evaluated the action of the antioxidant systems as a response to cellular infection. For this purpose, B. mori hybrid caterpillars of fifth instar were inoculated with a suspension of 7.8 × 107 POB ml-1 and, from the first to the eighth day post-inoculation (dpi), segments of the midgut were collected and processed for light and electronic microscopy. The nuclei of columnar cells showed polyhedric occlusion bodies in the seventh dpi and fragmentation of those cells, with peritrophic matrix disorganization. Analysis of antioxidant systems shows some moments of changes of the catalase enzymes and superoxide dismutase. Analysis of the cholinergic system revealed changes only at the beginning of the infection. Thus, the article acknowledges the antioxidant system as a barrier to stop viral infection, albeit it cannot stop infection from occurring, once a coevolutionary bond is maintained between virus and host.

Cytopathological process by multiple nucleopolyhedrovirus in the testis of Bombyx mori L., 1758 (Lepidoptera: Bombycidae).

A cytopathological methodology was used to analyze infection by Bombyx mori multiple nucleopolyhedrovirus (BmMNPV), a geographic isolate of the family Baculoviridae, in the caterpillar testes of the B. mori. Japanese B. mori strain caterpillar, fifth instar, were inoculated with BmMNPV and their testes were collected and processed for light and transmission electronic microscopy. Epithelial coating cells and interfollicular septa in testes were susceptible to BmMNPV. The first evidence of infection was detected on the 6th day post-inoculation (p.i.) in the external epithelium, and on the 7th day p.i. in the internal epithelium and interfollicular septa. Cytopathological characteristics consisted of hypertrophied nuclei, the formation of virogenic stroma, and the occlusion of virions in polyhedron protein crystals in several stages of development. At the end of the infectious process, cell lysis and release of polyhedra into the extracellular medium occurred. Histopathology revealed early infection foci in the surrounding regions of tracheal insertions, thus underlining the role of the trachea as an infection-spreading organ in insects. This spreading occurs through penetration of the basal lamina, which facilitates entry of the budded virus into the testis. Additionally, an alignment of a partial sequence of the ORF 14 of the BmMNPV geographic isolate with other NPV certified the virus genera.

Analysis of the muscle tissue of Wistar rats submitted to the sciatic nerve compression model and cryotherapy.

OBJECTIVE: To evaluate the effects of right sciatic nerve compression and cryotherapy on muscle tissue. METHODS: We used 42 male Wistar rats, subdivided in the following Groups Control, Injury 3, Injury 8 and Injury 15 submitted to nerve compression and euthanized in the 3rd, 8th and 15th day after surgery. The Cryotherapy Injury 3 was entailed treatment with cryotherapy by immersion of the animal in recipient for 20 minutes during 1 day, then animals were euthanized at the 3rd day after surgery, and the Cryotherapy Injury 8 and the Cryotherapy Injury 15 was treated for 6 days, and euthanized at the 8th and 15th day after surgery. Functional evaluation was performed by the grasping strength of the right pelvic limb. The right tibialis anterior muscles were evaluated for mass, smaller diameter and cross-sectional area. In the Cryotherapy Injury 8 and the Cryotherapy Injury 15 groups, the hydroxyproline was dosed in the right soles. RESULTS: In the compression there was a significant difference in the Injury Groups compared with the Control Group (p<0.05). In the smaller diameter, the compression in Control Group was higher than Injury 8 (p=0.0094), Injury 15 (p=0.002) and Cryotherapy Injury 15 (p<0.001) groups. The comparison between groups with euthanasia in the same post-operative period, a significant difference (p=0.0363) was seen in day 8th after surgery, and this result in Cryotherapy Injury Group was greater than Injury Group. In the fiber area, Control Group was also higher than the Injury 8 (p=0.0018), the Injury 15 (p<0.001) and the Cryotherapy Injury 15 (p<0.001). In hydroxyproline, no significant difference was seen between groups. CONCLUSION: Nerve damage resulted in decreased muscle strength and trophism, the cryotherapy delayed hypotrophy, but this effect did not persist after cessation of treatment.

Association of sericin and swimming on the phenotype, motor plate, and functionality of the denervated plantar muscle of Wistar rats.

Physical exercise may help maintain muscle properties and functional improvement after peripheral nerve lesion, which may be enhanced by using biocompatible substances, such as sericin. The aim of this study was analyse the effect of sericin associated with swimming exercise on the phenotype, innervation, and functionality of the plantar muscle of Wistar rats. Forty randomly divided adult rats were used in five groups of eight animals: control, injury, sericin, exercise, exercise and sericin. The application of sericin was done on the spot, 100 µL, shortly after nerve compression. Three days after sciatic nerve compression, the swimming and swimming and sericin groups were submitted to physical swimming exercise for 21 days. Afterwards, the animals were euthanised and the plantar muscle was dissected and submitted to histochemical and histoenzymological techniques. The grip strength test did not show alterations in muscular functionality, and the control presented greater muscle mass in relation to the other groups, the same did not occur for muscle length. Polymorphic neuromuscular junctions were detected in the groups, although without significant morphometric alterations of the area, major and minor diameters. The percentage of type I fibres was lower in the lesion group and there was no difference in fibres IIa and IIb between groups. The area of fibres I, IIa and IIb remained constant between groups. Sericin biopolymer combined with swimming exercise did not affect plantar muscle function, submitted to experimental axonotmosis, whose contractile properties were altered by nerve injury.

Neurotrophin expression and histomorphometric evaluation in Wistar rats subjected to neural mobilization after compression of the median nerve.

OBJECTIVE: To evaluate the neurotrophin mRNA expression and axon count in the median nerve of Wistar rats submitted to neural mobilization (NM) after nerve compression. METHODS: Eighteen animals were randomly divided into G1 (nerve compression only), G2 (NM for 1 min), and G3 (NM for 3 min). For NM, the animals were anesthetized and the right scapula received the mobilization, adapted as indicated for humans, on alternate days, from the third to the 13th postoperative (PO) day, totaling six days of therapy. On the 14th PO day, animals were anesthetized and euthanized. Fragments of the median nerve, distal to the compression procedure, were removed for histomorphometric analysis and expression of neurotrophins, nerve growth factor (NGF), and brain-derived neurotrophic factor (BDNF) by RT-PCR. RESULTS: Histomorphometric analysis revealed differences in the number of axons in the injured side, which was significantly lower in the injured limb nerve compared to the control limb, whereas the RT-PCR analysis showed no significant differences in the expression of NGF or BDNF. CONCLUSION: NM treatment did not affect median nerve regeneration, which maintained normal recovery rates.

OBJETIVO: Avaliar a expressão de RNAm de neurotrofinas e a contagem de axônios no nervo mediano de ratos Wistar submetidos à mobilização neural (MN) após compressão nervosa. MÉTODOS: Foram divididos aleatoriamente 18 animais em G1 (apenas compressão nervosa), G2 (MN por 1 minuto) e G3 (MN por 3 minutos). Para a MN, os animais foram anestesiados e o membro escapular direito recebeu a mobilização, adaptada da forma indicada para humanos, em dias alternados, do terceiro ao 13° dia de pós-operatório (PO), em seis dias de terapia. No 14° dia PO, os animais foram anestesiados e eutanasiados. Fragmentos do nervo mediano, distais ao procedimento de compressão, foram retirados para análise histomorfométrica e de expressão das neutrotrofinas, fator de crescimento do nervo (NGF) e fator de crescimento derivado do cérebro (BNDF) por RT-PCR. RESULTADOS: A análise histomorfométrica evidenciou diferenças no número de axônios nos lados lesionados, que foi significativamente menor no nervo do membro lesado comparado com o membro controle; por sua vez, a análise por RT-PCR não apontou diferenças significativas na expressão de NGF e nem de BNDF. CONCLUSÃO: O tratamento de MN não afetou a regeneração do nervo mediano, que manteve índices normais de recuperação.

Sericin and swimming on histomorphometric parameters of denervated plantar muscle in Wistar rats.

Objective To analyze the combined effects of the silk protein sericin and swimming exercise on histomorphometry of the plantar muscle in Wistar rats. Methods Forty adult rats were randomly allocated into 5 groups comprising 8 animals each, as follows: Control, Injury, Sericin, Swim, and Swim plus Sericin. Three days after crushing of the sciatic nerve the rats in the Swim and Swim plus Sericin Groups were submitted to swimming exercise for 21 days. Rats were then euthanized and the plantar muscle harvested and processed. Results Cross-sectional area, peripheral nuclei and muscle fiber counts, nucleus/fiber ratio and smallest muscle fiber width did not differ significantly between groups. Morphological analysis revealed hypertrophic fibers in the Swim Group and evident muscle damage in the Swim plus Sericin and Injury Groups. The percentage of intramuscular collagen was apparently maintained in the Swim Group compared to remaining groups. Conclusion Combined treatment with sericin and swimming exercise did not improve muscle properties. However, physical exercise alone was effective in maintaining intramuscular connective tissue and preventing progression of deleterious effects of peripheral nerve injury.

Effect of probiotic therapy on periodontal tissues and intestinal mucosa of rats with ligature-induced periodontitis / Efeito da terapia probiótica nos tecidos periodontais e mucosa intestinal de ratos com periodontite induzida por ligadura

INTRODUCTION: As periodontitis is caused by dysbiotic biofilm, it is believed that therapy with probiotics can act to control the mechanisms of adhesion and colonization, competing with invading microorganisms. OBJECTIVE: Evaluate probiotic therapy effect on periodontal tissues and intestinal mucosa of rats with ligature-induced periodontitis. METHODS: 32 Wistar rats were divided into four groups (n=8): Control Group (CG); Periodontal disease (PD); Probiotic (PROB); PD + probiotic (PDPRO). PD and PDPRO received a ligature over the first lower molars and PROB and PDPRO the probiotic Lactobacillus acidophilus based were given orally for 44 days. The animals were euthanized and the blood was collected for evaluation of triglyceride and cholesterol concentrations. The hemimandibles were collected for histomorphometric and radiographic analysis. The duodenum was removed for morphological evaluation and gingival tissue around the molars was collected for analysis of IL-17. RESULTS: The ANOVA one-way test was used followed by Tukey Test. PDPRO had a significantly lower bone loss than the PD (p<0.05) and a smaller number of osteoclasts on PDPRO when compared to the PD. As for IL-17, there was a decrease in the PDPRO when compared to the PD. The histomorphometry of the duodenum showed that there was a significant increase in the width of the villi in PROB only. CONCLUSION: The therapy with probiotics was effective to avoid the development of periodontitis by reducing alveolar bone loss and inflammation modulation and increasing the width of the duodenum villi, which may help to restabilize the balance of the gastrointestinal tract.

INTRODUÇÃO: Como a periodontite é causada por biofilme disbiótico, acredita-se que a terapia com probióticos possa atuar no controle dos mecanismos de adesão e colonização, competindo com microrganismos invasores. OBJETIVO: Avaliar o efeito da terapia probiótica nos tecidos periodontais e mucosa intestinal de ratos com periodontite induzida por ligadura. MÉTODOS: 32 ratos Wistar foram divididos em quatro grupos (n=8): Grupo Controle (GC); Doença periodontal (PD); Probiótico (PROB); PD + probiótico (PDPRO). PD e PDPRO receberam ligadura sobre os primeiros molares inferiores e PROB e PDPRO, o probiótico à base de Lactobacillus acidophilus dado via oral por 44 dias. Os animais foram sacrificados e o sangue coletado para avaliação das concentrações de triglicerídeos e colesterol total. As hemimandíbulas foram coletadas para análise histomorfométrica e radiográfica. O duodeno foi removido para avaliação morfológica e o tecido gengival ao redor dos molares foi coletado para análise de IL-17. RESULTADOS: Foi usado Teste ANOVA seguido pelo Teste de Tukey. PDPRO teve uma perda óssea significativamente menor do que o PD (p<0.05) e um menor número de osteoclastos no PDPRO quando comparado ao PD. Já para IL-17, houve diminuição do PDPRO em relação ao PD. A histomorfometria do duodeno mostrou que houve aumento significativo da largura das vilosidades no PROB somente. CONCLUSÃO: A terapia com probiótico foi eficaz para evitar o desenvolvimento de periodontite por reduzir a perda óssea alveolar e a modulação da inflamação e aumentar a largura das vilosidades duodenais, o que pode ajudar a estabilizar o equilíbrio do trato gastrointestinal.

Action of vanillin (Vanilla planifolia) on the morphology of tibialis anterior and soleus muscles after nerve injury.

OBJECTIVE: To evaluate the action of vanillin (Vanilla planifolia) on the morphology of tibialis anterior and soleus muscles after peripheral nerve injury. METHODS: Wistar rats were divided into four groups, with seven animals each: Control Group, Vanillin Group, Injury Group, and Injury + Vanillin Group. The Injury Group and the Injury + Vanillin Group animals were submitted to nerve injury by compression of the sciatic nerve; the Vanillin Group and Injury + Vanillin Group, were treated daily with oral doses of vanillin (150mg/kg) from the 3rd to the 21st day after induction of nerve injury. At the end of the experiment, the tibialis anterior and soleus muscles were dissected and processed for light microscopy and submitted to morphological analysis. RESULTS: The nerve compression promoted morphological changes, typical of denervation, and the treatment with vanillin was responsible for different responses in the studied muscles. For the tibialis anterior, there was an increase in the number of satellite cells, central nuclei and fiber atrophy, as well as fascicular disorganization. In the soleus, only increased vascularization was observed, with no exacerbation of the morphological alterations in the fibers. CONCLUSION: The treatment with vanillin promoted increase in intramuscular vascularization for the muscles studied, with pro-inflammatory potential for tibialis anterior, but not for soleus muscle. OBJETIVO: Avaliar a ação da vanilina (Vanilla planifolia) sobre a morfologia dos músculos tibial anterior e sóleo após lesão nervosa periférica. MÉTODOS: Ratos Wistar foram divididos em quatro grupos, com sete animais cada, sendo Grupo Controle, Grupo Vanilina, Grupo Lesão e Grupo Lesão + Vanilina. Os animais dos Grupos Lesão e Grupo Lesão + Vanilina foram submetidos à lesão nervosa por meio da compressão do nervo isquiático, e os Grupos Vanilina e Grupo Lesão + Vanilina foram tratados diariamente com doses orais de vanilina (150mg/kg) do 3o ao 21o dia após a indução da lesão nervosa. Ao término do experimento, os músculos tibial anterior e sóleo foram dissecados e seguiram o processamento de rotina em microscopia de luz, para posterior análise morfológica. RESULTADOS: A compressão nervosa promoveu alterações morfológicas características de denervação, sendo que o tratamento com vanilina foi responsável por respostas distintas nos músculos estudados. Para o tibial anterior, houve aumento do número de células satélites, núcleos centrais e atrofia das fibras, bem como desorganização fascicular. Já no sóleo, houve apenas aumento da vascularização, sem exacerbação das alterações morfológicas nas fibras. CONCLUSÃO: O tratamento com vanilina promoveu o aumento da vascularização intramuscular para os músculos estudados, com potencial pró-inflamatório para o tibial anterior, o que não ocorreu no músculo sóleo.

Jumping in aquatic environment after sciatic nerve compression: nociceptive evaluation and morphological characteristics of the soleus muscle of Wistar rats.

OBJECTIVE: To evaluate the effect of jumping in aquatic environment on nociception and in the soleus muscle of trained and not trained Wistar rats, in the treatment of compressive neuropathy of the sciatic nerve. METHODS: Twenty-five Wistar rats were distributed into five groups: Control, Lesion, Trained + Lesion, Lesion + Exercise, and Trained + Lesion + Exercise. The training was jumping exercise in water environment for 20 days prior to injury, and treatment after the injury. Nociception was evaluated in two occasions, before injury and seven after injury. On the last day of the experiment, the right soleus muscles were collected, processed and analyzed as to morphology and morphometry. RESULTS: In the assessment of nociception in the injury site, the Control Group had higher average than the rest, and the Lesion Group was larger than the Trained + Lesion and Lesion + Exercise Groups. The Control Group showed higher nociceptive threshold in paw, compared to the others. In the morphometric analysis, in relation to Control Group, all the injured groups showed decreased muscle fiber area, and in the Lesion Group was lower than in the Lesion + Exercise Group and Trained + Lesion Group. Considering the diameter of the muscle fiber, the Control Group had a higher average than the Trained + Lesion Group and the Trained + Lesion + Exercise Group; and the Lesion Group showed an average lower than the Trained + Lesion and Lesion + Exercise Groups. CONCLUSION: Resistance exercise produced increased nociception. When performed prior or after nerve damage, it proved effective in avoiding hypotrophy. The combination of the two protocols led to decrease in diameter and area of the muscle fiber. OBJETIVO: Avaliar os efeitos do salto em meio aquático, na nocicepção e no músculo sóleo, em ratos Wistar treinados e não treinados, no tratamento de neuropatia compressiva do nervo isquiático. MÉTODOS: Foram distribuídos em cinco grupos 25 ratos Wistar: Controle, Lesão, Treinado + Lesão, Lesão + Exercício e Treinado + Lesão + Exercício. O treino foi com exercício de salto em meio aquático durante 20 dias, prévio à lesão, e o tratamento ocorreu após a lesão. Foram realizadas avaliações da nocicepção, sendo uma pré-lesão e sete pós-lesão. No último dia de experimento, os músculos sóleos direitos foram coletados, processados e analisados por meio de morfologia e morfometria. RESULTADOS: Na avaliação da nocicepção no local da lesão, o Grupo Controle apresentou média maior que os demais, e o Grupo Lesão foi maior que os Grupos Treinado + Lesão e Lesão + Exercício. O Grupo Controle apresentou limiar nociceptivo na pata maior com relação aos demais. Nas análises morfométricas, em relação ao Grupo Controle, todos os grupos lesionados apresentaram diminuição da área da fibra muscular; o Grupo Lesão apresentou-se menor que os Grupos Treinado + Lesão e Lesão + Exercício. No diâmetro da fibra muscular, o Grupo Controle apresentou média maior que os Grupos Treinado + Lesão e Treinado + Lesão + Exercício, e o Grupo Lesão apresentou média menor que os Grupos Treinado + Lesão e Lesão + Exercício. CONCLUSÃO: O exercício físico resistido produziu aumento da nocicepção. Quando realizado previamente ou após a lesão nervosa, mostrou-se eficaz em evitar a hipotrofia. A associação dos dois protocolos levou à diminuição do diâmetro e da área da fibra muscular.

Therapeutic ultrasound after sciatic nerve compression of Wistar rats.

OBJECTIVES: The present study analyzed the effect of therapy with therapeutic ultrasound on the sciatic nerve after compression injury, comparing two similar doses of SATA. METHODS: In total, 32 Wistar rats were used, divided into the following groups: CG - control; IG - compression injury of the sciatic nerve; IGCU - injury and continuous ultrasound; and IGPU - injury and 20% pulsed ultrasound. The treatment with ultrasound started on the 3rd postoperative day, with a frequency of 1 MHz, 0.4 W/cm² (SATA) for IGCU. IGPU received 2.0 W/cm2 (SATP), with 20% of the active cycle, for 3 minutes. The treatment was performed on a daily basis, totaling 15 days of therapy. Evaluations were performed for functional, histological, and morphometric forms. RESULTS: Both the Sciatic Functional Index and the withdrawal threshold and grip strength failed to show an advantage of using therapeutic ultrasound. For the morphometric evaluations of nerve fiber diameter and axons, myelin sheath thickness, and G quotient and nerve fiber estimates, IGPU values were estimated to be significantly lower. The morphological analysis revealed intense inflammatory response and neovascularization, as well as degeneration of axons and the myelin sheath, for the injury group and IGCU; however, IGPU showed greater tissue disorganization. CONCLUSION: There were no significant differences, showing functional or nocicepitive recovery of the treated groups, including with characteristics pointing to the pulsed group with worse results.

Experimental Periodontitis in the Potentialization of the Effects of Immobilism in the Skeletal Striated Muscle.

This study aims to evaluate if ligature-induced periodontitis can potentiates the deleterious effects of immobilization in the skeletal striated muscle, contributing to the development of muscle atrophy due to disuse. Forty Wistar rats were divided into four groups: (1) Control Group (CG), (2) Periodontal Disease (PDG), (3) Immobilized (IG), and (4) Immobilized with Periodontal Disease (IPDG). Periodontal disease was induced for 30 days, with ligature method, and the immobilization was performed with cast bandage for 15 days. Prior to euthanasia, nociceptive threshold and muscular grasping force were evaluated. Afterwards, the soleus muscle was dissected and processed for sarcomere counting and morphological/morphometric analysis. For data analysis, was used the one-way ANOVA and post-test Tukey (p < 0.05). The IG and IPDG presented lower muscle weight, lower muscular grip strength, and less number of sarcomeres compared to CG. The PDG showed reduction of muscle strength and nociceptive threshold after 15 days of periodontal disease and increased connective tissue compared to CG. The IPDG presented lower muscle length and nociceptive threshold. The IG presented reduction in cross-sectional area and smaller diameter, increase in the number of nuclei and a nucleus/fiber ratio, decrease in the number of capillaries and capillary/fiber ratio, with increase in connective tissue. The IPDG had increased nucleus/fiber ratio, decreased capillaries, and increased connective tissue when compared to the IG. The IPDG presented greater muscle tissue degeneration and increased inflammatory cells compared to the other groups. Ligature-induced periodontitis potentiated the deleterious effects of immobilization of the skeletal striated muscle.

Silkworm Sericin: Properties and Biomedical Applications.

Silk sericin is a natural polymer produced by silkworm, Bombyx mori, which surrounds and keeps together two fibroin filaments in silk thread used in the cocoon. The recovery and reuse of sericin usually discarded by the textile industry not only minimizes environmental issues but also has a high scientific and commercial value. The physicochemical properties of the molecule are responsible for numerous applications in biomedicine and are influenced by the extraction method and silkworm lineage, which can lead to variations in molecular weight and amino acid concentration of sericin. The presence of highly hydrophobic amino acids and its antioxidant potential make it possible for sericin to be applied in the food and cosmetic industry. The moisturizing power allows indications as a therapeutic agent for wound healing, stimulating cell proliferation, protection against ultraviolet radiation, and formulating creams and shampoos. The antioxidant activity associated with low digestibility of sericin that expands the application in the medical field, such as antitumour, antimicrobial and anti-inflammatory agent, anticoagulant, acts in colon health, improving constipation and protects the body from obesity through improved plasma lipid profile. In addition, the properties of sericin allow its application as a culture medium and cryopreservation, in tissue engineering and for drug delivery, demonstrating its effective use, as an important biomaterial.