Simulated weightlessness led to the transformation of glycolipid metabolism in the livers of mice / La antigravedad simulada provocó la transformación del metabolismo de los glicolípidos en el hígado de ratones / Antigravidade simulada levou à transformação do metabolismo de glicolipídios no fígado de camundongos

ABSTRACT Objectives: The effects of weightlessness on the liver were studied using a tail suspension (TS) male mouse model. Methods: The effects of 0-, 2- and 4-week TS (CON, TS2 and TS4 groups) on glycogen and lipid content, as well as on the molecular processes of the synthesis and degradation pathways, were examined. Results: (1) The number of glycogenosomes under ultrastructure and the glycogen content were considerably larger in the TS4 group than in the other two groups. (2) In the TS4 group, glycogen synthase activity remained constant while glycogen phosphorylase activity dropped, indicating that glycogen breakdown was reduced. (3) The livers of the TS2 group had the highest lipid and triglyceride content, indicating lipid buildup in the liver at this time. (4) In the TS2 group, the activities of the fatty acid synthesis-related factors acetyl-CoA carboxylase and fatty acid synthase increased, while hepatic lipase decreased, indicating that lipid synthesis increased, while decomposition decreased. (5) In the TS2 group, the protein expression of glucose transporters 1 and 2 increased. Conclusions: From TS2 weeks to TS4 weeks, the main energy consumption mode in the livers of mice transitioned from glucose metabolism to lipid metabolism as glucose use decreased. Level of evidence II; Comparative prospective study.

RESUMEN Objetivos: Se estudiaron los efectos de la antigravedad en el hígado utilizando un modelo de ratón macho en prueba de suspensión de la cola (TS, tail suspension). Métodos: Se examinaron los efectos de la TS a las 0, 2 y 4 semanas (grupos CON, TS2 y TS4) sobre el contenido de glucógeno y lípidos, así como sobre los procesos moleculares de las vías de síntesis y degradación. Resultados: (1) El número de glucogenosomas ultraestructurales y el contenido de glucógeno fueron expresivamente más altos en el grupo TS4 que en los otros dos grupos. (2) En el grupo TS4, la actividad de la glucógeno sintasa se mantuvo constante, mientras que la actividad de la glucógeno fosforilasa disminuyó, lo que indica que la degradación del glucógeno se redujo. (3) Los hígados del grupo TS2 presentaron el mayor contenido de lípidos y triglicéridos, lo que indica la acumulación de lípidos en el hígado en ese momento. (4) En el grupo TS2, la actividad de los factores relacionados con la síntesis de ácidos grasos acetil-CoA carboxilasa y ácido graso sintasa aumentó, mientras que la lipasa hepática disminuyó, indicando que la síntesis de lípidos aumentó mientras que la descomposición disminuyó. (5) En el grupo TS2, la expresión proteica de los transportadores de glucosa 1 y 2 aumentó. Conclusiones: Desde la semana TS2 hasta la semana TS4, el principal modo de consumo de energía en el hígado de los ratones pasó del metabolismo de la glucosa al metabolismo de los lípidos a medida que disminuía el uso de la glucosa. Nivel de Evidencia II, Estudio retrospectivo comparativo.

RESUMO Objetivos: Os efeitos da antigravidade no fígado foram estudados usando um modelo de camundongo macho com a suspensão pela cauda (TS, tail suspension). Métodos: Foram examinados os efeitos da TS em 0, 2 e 4 semanas (grupos CON, TS2 e TS4) sobre o conteúdo de glicogênio e lipídios, bem como nos processos moleculares das vias de síntese e degradação. Resultados: (1) O número de glicogenossomos ultraestruturais e o teor de glicogênio foram expressivamente maiores no grupo TS4 do que nos outros dois grupos. (2) No grupo TS4, a atividade de glicogênio sintase permaneceu constante, enquanto a atividade de glicogênio fosforilase caiu, indicando que a degradação do glicogênio foi reduzida. (3) Os fígados do grupo TS2 tiveram o maior teor lipídico e de triglicérides, indicando acúmulo de lipídios no fígado no momento. (4) No grupo TS2, a atividade dos fatores relacionados com a síntese de ácidos graxos acetil-CoA carboxilase e ácido graxo sintase aumentaram, enquanto a lipase hepática diminuiu, indicando que a síntese de lipídios aumentou, enquanto a decomposição diminuiu. (5) No grupo TS2, a expressão proteica dos transportadores de glicose 1 e 2 aumentou. Conclusões: De TS2 semanas para TS4 semanas, o principal modo de consumo de energia no fígado de camundongos passou do metabolismo da glicose para o metabolismo lipídico, à medida que o uso de glicose diminuiu. Nível de evidência II, Estudo retrospectivo comparativo.

Effects of repetitive transcranial magnetic stimulation on neuronal excitability and ion channels in hindlimb unloading mice / 生物医学工程学杂志

Weightlessness in the space environment affects astronauts' learning memory and cognitive function. Repetitive transcranial magnetic stimulation has been shown to be effective in improving cognitive dysfunction. In this study, we investigated the effects of repetitive transcranial magnetic stimulation on neural excitability and ion channels in simulated weightlessness mice from a neurophysiological perspective. Young C57 mice were divided into control, hindlimb unloading and magnetic stimulation groups. The mice in the hindlimb unloading and magnetic stimulation groups were treated with hindlimb unloading for 14 days to establish a simulated weightlessness model, while the mice in the magnetic stimulation group were subjected to 14 days of repetitive transcranial magnetic stimulation. Using isolated brain slice patch clamp experiments, the relevant indexes of action potential and the kinetic property changes of voltage-gated sodium and potassium channels were detected to analyze the excitability of neurons and their ion channel mechanisms. The results showed that the behavioral cognitive ability and neuronal excitability of the mice decreased significantly with hindlimb unloading. Repetitive transcranial magnetic stimulation could significantly improve the cognitive impairment and neuroelectrophysiological indexes of the hindlimb unloading mice. Repetitive transcranial magnetic stimulation may change the activation, inactivation and reactivation process of sodium and potassium ion channels by promoting sodium ion outflow and inhibiting potassium ion, and affect the dynamic characteristics of ion channels, so as to enhance the excitability of single neurons and improve the cognitive damage and spatial memory ability of hindlimb unloading mice.

Histological analysis of the effects of electroacupuncture stimulation on the femur fracture line in a rat model of hindlimb immobilization / 全日本鍼灸学会雑誌

[Introduction] This study compared the effects of joint immobilization and concurrent electroacupuncture stimulation on fracture line appearance, which is indicative of differences in cortical bone structure, in the femurs of young adult rats. [Materials and Methods] Forty-two 7-week-old Wistar rats were divided into three groups: a hindlimb immobilized group (IM), a hindlimb immobilized group with concurrent electroacupuncture stimulation (IMEA), and an untreated control group (CO). IM and IMEA were immobilized for two weeks with a jacket-type immobilization device that immobilized the hip joint in extension and restricted hip joint adduction and abduction. Acupuncture needles were inserted into the femoral region during the immobilization period in the IMEA group, and continuous alternating current was used for stimulation. A low-frequency stimulator was used to generate electrical current (250 μsec, 50 Hz, 0.24 mA, 500 Ω load resistance), and stimulation was performed daily for two weeks at 10 min/day. The extracted femur was fractured from the anterior part of the diaphysis or metaphyseal end by three-point-bending under constant conditions with 10 mm between the fulcrum and a crosshead speed of 10 mm/min. [Results] IM showed significantly lower Stiffness, Deformation, and Strength values than CO. Bone morphometry parameters also showed lower values for IM. A cement line was observed between lamellar and non-lamellar bone in CO and IMEA, but was indistinct in IM. In CO and IMEA, minute bone fragments were formed in the deep diaphysis region sandwiched between the inner and outer circumferential lamellae, but no such fragments were found in IM. IMEA had less resorption than IM, and lamellar bone with a structure similar to CO was maintained. Moreover, cracks observed in CO and IMEA ran longitudinally in the vicinity of the cement line and rest line, but no such cracks were found in IM. [Discussion and Conclusion] These findings suggest that electroacupuncture mitigates bone weakening in immobilized rat femurs, and this affects the appearance of the fracture line.

Ginsenoside Rb1 promotes angiogenesis potentially by activating the JAK-STAT3 signalling pathway

Conventional revascularization strategies for ischemic heart disease (IHD) are designed to prompt reperfusion of the coronary artery to the salvaged cardiomyocytes. However, these strategies may cause myocardial reperfusion injuries. Therefore, a safe and effective strategy needs to be developed to improve the conventional strategies. Here, we investigated the pro-angiogenic effect of Ginsenoside Rb1 (Rb1) to provide the experimental basis for angiogenesis-mediated drug therapy of IHD. Thus, Human umbilical vein endothelial cells (HUVECs) were treated with either a vehicle or Rb1 at 4, 8, 12 or 16 ?M for 24 h. A model of hindlimb ischemia was established using C57BL/6J mice. In sham-operated mice, only the femoral artery was isolated without ligation whereas the other operations and supplementation control group were consistent. The mice in the supplementation group were injected with Rb1 (50 mg/kg body wt./day) for 7 days. The results indicated that Rb1 promotes cell proliferation, adhesion, migration and tube formation in the HUVECs in a dose-dependent manner. The ED50 of Rb1 to improve cell adhesion is 8 ?M. In mice, Rb1 promoted angiogenesis after the ligation of the femoral artery and ameliorated the ischemic conditions. Intriguingly, more blood flow recovery was observed in the Rb1 supplemented mice than in the vehicle-treated mice (0.85 ± 0.05 vs. 0.71±0.10 on day 3; 0.94±0.10 vs. 0.75±0.08 on day 7). In HUVECs, Rb1 increased the phosphorylation of STAT3 and JAK, which may be the mechanism through which Rb1 mitigates IHD. Moreover, our results confirmed that Rb1mitigates IHD potentially by activating the JAK-STAT3 pathway. Further clinical trials are warranted to verify the clinical implications of Rb1.

Core training under suspension exercise therapy on treatment of low back pain / Treinamento de core com terapia de exercícios de suspensão para a dor lombar / Entrenamiento del core con terapia de ejercicios en suspensión para el dolor lumbar

ABSTRACT Introduction: The main clinical feature of chronic nonspecific low back pain (CNLBP) is lower back pain, and suspension sports therapy has a specific effect in this case. Objective: To investigate the changes of flexion-relaxation phenomenon in patients with lower back pain after core control training of suspension exercise therapy (SET). Methods: 84 subjects who met the inclusion and exclusion criteria of chronic low back pain in this experiment were randomly divided into an experimental group and a control group. The experimental group was treated with suspension training. The control group only received acupuncture. We then determined the muscle fascia tension and core stability of the lower lumbar region. Results: The visual analog scale (VAS) and Oswestry dysfunction index (ODI) evaluations of the two groups of patients were different. Conclusion: Suspended core stabilization training has a significant long-term effect in reducing lower back pain and improving waist function in patients with chronic nonspecific low back pain. Level of evidence II; Therapeutic studies - investigation of treatment results.

RESUMO Introdução: A característica clínica principal da dor lombar crônica não especifica (CNLBP) é dor na região lombar. A terapia esportiva por suspensão tem um efeito específico neste caso. Objetivo: Investigar as mudanças do fenômeno flexão- relaxamento em pacientes com dor lombar após treinamento de controle core com terapia de exercícios de suspensão (SET). Métodos: 84 indivíduos que preencheram os critérios de inclusão e exclusão para dor lombar crônica neste experimento foram aleatoriamente divididos em um grupo experimental e um grupo de controle. O grupo experimental foi tratado com treinamento de suspensão. O grupo de controle recebeu apenas acupuntura. Determinamos então a tensão da fáscia muscular e a estabilidade core da região lombar. Resultados: Avaliações da escala visual analógica (EVA) e do índice de incapacidade Owestry (ODI) dos dois grupos de pacientes tiveram resultados diferentes. Conclusão: O treinamento de estabilização do core por suspensão tem efeito de longo prazo considerável na redução de dor lombar e a recuperação da função da cintura em pacientes com dor lombar não especifica crônica. Nível de evidência II; Estudos terapêuticos - investigação de resultados de tratamento.

Resumen Introducción: La característica clínica principal del dolor lumbar crónico inespecífico (CNLBP) es dolor en la región lumbar. La terapia deportiva en suspensión tiene un efecto específico en este caso. Objetivo: Investigar los cambios del fenómeno flexión-relajamiento en pacientes con dolor lumbar tras el entrenamiento de control de core con terapia de ejercicios en suspensión (SET). Métodos: Se dividió aleatoriamente los 84 individuos que rellenaron los criterios de inclusión y exclusión para dolor lumbar crónico en este experimento en un grupo experimental y un grupo de control. El grupo experimental fue tratado con entrenamiento en suspensión. El grupo de control recibió apenas acupuntura. Determinamos, entonces, la tensión de la fascia muscular y la estabilidad core de la región lumbar. Resultados: Evaluaciones de escala visual analógica (EVA) y del índice de discapacidad Owestry (ODI) de los dos grupos tuvieron resultados diferentes. Conclusión: El entrenamiento de estabilización del core por suspensión tiene efecto de largo plazo considerable en la reducción de dolor lumbar y la recuperación de la función de la cintura en pacientes con dolor lumbar inespecífico crónico. Nivel de evidencia II; Estudios terapéuticos - investigación de resultados de tratamiento.

Application of temperature-sensitive chitosan hydrogel encapsulated exosomes in ischemic diseases / 中国组织工程研究

BACKGROUND: Exosomes derived from mesenchymal stem cells can reduce myocardial ischemia and reperfusion injury, but there are some problems such as short half-life, fast clearance and low targeting. OBJECTIVE: To modify and encapsulate exosomes with temperature-sensitive chitosan hydrogel to increase the retention rate of exosomes in the body, and to achieve better therapeutic effect. METHODS: Cell transfection method was used to knock down piR823 in exosomes derived from umbilical cord mesenchymal stem cells, and the effect of knockdown of piR823 exosomes on the proliferation and apoptosis of C2C12 cells was detected. Chitosan/β-sodium glycerophosphate temperature-sensitive hydrogel was prepared and mixed directly with exosomes to prepare chitosan/β-sodium glycerophosphate temperature-sensitive hydrogel encapsulated with exosomes. The gel-forming properties, rheology and in vitro sustained release properties of the hydrogel after encapsulation of exosomes were tested. Thirty C57BL/6J mice were taken to establish hind limb ischemia models, and randomly divided into five groups. The gastrocnemius of group A was injected with PBS; group B was injected with chitosan/β-sodium glycerophosphate temperature-sensitive hydrogel; and group C was injected with exosomes-encapsulated chitosan/β-sodium glycerophosphate temperature-sensitive hydrogel; group D was injected with exosomes; group E was injected with exosomes knocking down piR823. Limb function and recovery, blood flow, grip strength, exercise endurance and muscle regeneration were detected in each group. RESULTS AND CONCLUSION: (1) Exosomes knocking down piR823 inhibited the proliferation of C2C12 cells; normal exosomes inhibited hydrogen peroxide-induced apoptosis of C2C12 cells. The inhibitory effect of exosomes on apoptosis was weakened after piR823 was knocked down. (2) The hydrogel encapsulating exosomes had gel-forming properties, but the gel-forming time was shortened, and it could slowly and continuously release exosomes for more than 30 days. (3) After 28 days of hindlimb ischemia, the blood flow recovery of the left limb in group C was better than that in groups B and D (P < 0.05); it in group D was better than group E (P < 0.05); the grip strength, endurance, running time and distance of group C were better than those of groups D and B (P < 0.05), and above indexes in group D were better than in group E (P < 0.05). Muscle regeneration was better in group C than in groups B and D (P < 0.05), and it in group D was better than group E (P < 0.05). (4) The results showed that encapsulation of exosomes by chitosan/β-sodium glycerophosphate temperature-sensitive hydrogel prolonged the residence time of exosomes in vivo, significantly enhanced blood perfusion and recovery of tissue function after ischemia, and the treatment effect was more significant.

Short-term creatine supplementation changes protein metabolism signaling in hindlimb suspension

The effect of a short-term creatine supplementation on hindlimb suspension (HS)-induced muscle atrophy was investigated. Creatine monohydrate (5 g/kg b.w. per day) or placebo, divided in 2 daily doses, was given by oral gavage for 5 days. Rats were maintained in HS with dietary supplementation concomitantly for 5 days. Body weight, soleus and EDL muscle masses, and cross-sectional areas (CSA) of the muscle fibers were measured. Signaling pathways associated with skeletal muscle mass regulation (FST, MSTN, FAK, IGF-1, MGF, Akt, mTOR, atrogin-1, and MuRF1 expressions, and Akt, S6, GSK3B, and 4EBP1 proteins) were evaluated in the muscles. Soleus muscle exhibited more atrophy than the EDL muscle due to HS. Creatine supplementation attenuated the decrease of wet weight and increased p-4EBP1 protein in the EDL muscle of HS rats. Also, creatine increased mTOR and atrogin-1 expressions in the same muscle and condition. In the absence of HS, creatine supplementation increased FAK and decreased MGF expressions in the EDL muscle. Creatine attenuated the increase in FST expression due to HS in the soleus muscle. MuRF1 expression increased in the soleus muscle due to creatine supplementation in HS animals whereas atrogin-1 expression increased still further in this group compared with untreated HS rats. In conclusion, short-term creatine supplementation changed protein metabolism signaling in soleus and EDL muscles. However, creatine supplementation only slightly attenuated the mass loss of both muscles and did not prevent the CSA reduction and muscle strength decrease induced by HS for 5 days.

Electroacupuncture improves locomotor function by regulating expression of inflammation and oxidative stress-related proteins in mice with spinal cord injury / 针刺研究

OBJECTIVE: To observe the effect of electroacupuncture (EA) on the expression of apolipoprotein E (ApoE) and related proteins of inflammation and anti-oxidative stress in spinal cord in mice with spinal cord injury (SCI), so as to explore its mechanisms underlying function repair. METHODS: Thirty-six female C57BL/6 mice were equally randomized into 3 groups: sham operation, model and EA. The SCI model was established by clamping the spinal cord for 25 s with a serrefine after laminectomy of the 1st lumbar vertebra (L1). EA (1.5 Hz/7.5 Hz, 1.0 mA) was applied to bila-teral "Zusanli" (ST36) and "Sanyinjiao" (SP6) for 10 min, once a day for 7 days. The hindlimb locomotor function was assessed according to the state of the range of motion, coordination, claw gesture of the hind leg ankle-joint, trunk stabi-lity and the tail posture by using Basso Mouse Scale(BMS). The histopathological changes of the injured area of the spinal cord were determined by H.E. staining. The expression levels of ApoE, phosphorylated nuclear transcription factor-κB(p-NF-κB), interleukin 1 beta(IL-1β), phosphorylated extracellular regulatory protein kinase(p-ERK1/2), extracellular regulatory protein kinase(ERK1/2), nuclear factor erythroid 2-related factor 2(Nrf2) and heme oxidase-1(HO-1) in the spinal cord were detected by Western blot, and the glial fibrillary acidic protein (GFAP)-positive astrocytes were displayed by immunofluorescence staining. RESULTS: After modeling, the BMS scores were significantly decreased in the model group compared with the sham operation group (P<0.05). Following EA, the BMS scores were markedly increased in the EA group relevant to the model group (P<0.05), suggesting an improvement of the hindlimb locomotor function. H.E. stain showed structural disorder with lots of cavities, severe inflammatory infiltration with large quantity of inflammatory cells, and apparent reduction of normal neurons in the injured spinal cord tissue of model group, which was milder in the EA group. The expression levels of ApoE, p-NF-κB, IL-1β, p-ERK1/2 (not ERK1/2), Nrf2 and HO-1 were significantly increased in the model group than those in the sham operation group (P<0.05). Compared with the model group, the expression levels of ApoE, p-ERK1/2, Nrf2 and HO-1 were further notably up-regulated (P<0.05), and those of p-NF-κB and IL-1β proteins obviously down-regulated in the EA group (P<0.05). Immunoflorescence staining showed that the number of GFAP-positive cells was apparently increased in the model group compared with the sham operation group and observably decreased in the EA group relevant to the model group (P<0.05). CONCLUSION: EA can significantly improve locomotor function in SCI mice, which is associated with its effects in reducing inflammation, oxi-dative stress reactions and reactive astrocyte proliferation via up-regulating expression of ApoE, p-ERK1/2, and Nrf2/HO-1 (antioxidant pathway) and inhibiting IL-1β and NF-κB expression.

Sarcomere structure: the importance of desmin protein in muscle atrophy / Estructura de sarcómera: la importancia de proteína desmina en atrofia muscular

Knowing the ultrastructure of skeletal muscle is critical to understand how it works under normal situation and the disorders caused by extreme or pathological conditions. Sarcomere is the basic structural unit of striated muscle tissue. An important element of sarcomere architecture are the intermediate filaments, including the desmin protein. Desmin protein contributes to maintenance of cell integrity, efficient transmission of force and mechanochemical signaling within the myocyte. Because of this, desmin protein has constantly been a focus of research that investigates its alterations associated to damage and muscle atrophy under different conditions. The purpose of the following literature review is to describe the basic concepts of muscle ultrastructure, emphasizing the desmin protein role under conditions of muscle disuse atrophy and aging.

Conocer la ultraestructura del músculo esquelético es crítico para entender cómo trabaja bajo situaciones normales y en desórdenes causados por condiciones extremas o patológicas. La sarcómera es la unidad de estructura básica del tejido muscular estriado. Elementos importantes en la arquitectura de la sarcómera son los filamentos intermedios, incluyendo la proteína desmina. La proteína desmina contribuye en mantener la integridad celular, la transmisión eficiente de fuerza y la señalización mecanoquímica dentro del miocito. Debido a lo anterior, la proteína desmina ha sido constante foco de investigación en trabajos que estudian sus alteraciones asociadas a daño y atrofia muscular bajo diferentes condiciones. El propósito de la siguiente revisión de la literatura es describir los conceptos básicos de la ultraestructura muscular, enfatizando en el rol de la proteína desmina bajo condiciones de atrofia muscular por desuso y envejecimiento.

Effects of growth differentiation factor 11 on angiogenesis in diabetic hindlimb ischemia / 中华内分泌代谢杂志

Objective To investigate the effects and possible mechanism of growth differentiation factor 11 (GDF11)on angiogenesis in diabetic hindlimb ischemia. Methods Sixty SD rats were used in this study. Diabetes was induced by intraperitoneal injection of streptozotocin. 3 days after streptozotocin administration, 40 rats with plasma glucose concentration≥16.7 mmol/L were selected in the subsequent experiments. 12 weeks after diabetes was induced,the left femoral artery and all the sides branches were dissected free and excised. After resection of the left femoral artery,rats were randomized to four groups:PBS group(n=10),GDF11 group(n=10),IgG Ab group (n=10),or GDF11 Ab group(n=10). After 0,7,and 14 days,the serial blood flows were measured by a Laser Doppler perfusion image(LDPI)analyzer. To detect capillary endothelial cell,the sections of muscles were reacted with anti-CD31 monoclonal antibodies,and subsequently reacted with Cy3-conjugated anti-rabbit IgG antibody. The expression levels of HIF1α and VEGF were detected by western blotting. Results In GDF11 group significantly increased the blood perfusion and capillary density of ischemia hindlimb of the diabetic rats were found,which was correlated to an increased level of HIF1α and VEGF. In contrast, GDF11 Ab could lead to the opposite effects. Conclusion GDF11 treatment promotes the recovery of diabetic hindlimb ischemia, which may be related to the improvement of expression of HIF1 alpha and VEGF.

Postnatal variation of limb bones in the Japanese quail, Coturnix coturnix japonica / Variación postnatal de huesos de los miembros en la codorniz japonesa, Coturnix coturnix japonica

Changes in body size over ontogeny may influence the ontogenetic development of long bones, and thus important to our understanding of variation in morphological, physiological, and life-history traits within species. In this study, we sample the entire measurements of the Japanese quail (Coturnix coturnix japonica) of individual skeletons, to investigate the ontogenetic allometry of limb bone proportions by Reduced Major Axis (RMA) regression. The ulna and humerus were both positively allometric in relation to body mass, with their proximal ends growth more rapidly than other regions. Hindlimb bones exhibited more than one allometric pattern. The tarsometatarsus was negative; the femur presented positive allometry, with the width and depth of the proximal end scaled more strongly; measurements of the tibiotarsus were dominated by more rapid growth, especially the width of the proximal end. The growth patterns are suggested to be correlated with the ontogeny of behavior, and reflect the muscular requirements for different mode of locomotion.

Los cambios en el tamaño corporal sobre la ontogenia pueden influir en el desarrollo ontogenético de los huesos largos, y por lo tanto es importante conocer la variación en sus rasgos morfológicos, fisiológicos y la historia de vida dentro de las especies. En este estudio, se muestran las mediciones completas de esqueletos individuales de codorniz japonesa (Coturnix coturnix japonica), para investigar la alometría ontogenética de las proporciones de los huesos de los miembros mediante la regresión del Eje Mayor Reducido (RMA). La ulna y el húmero fueron ambos positivos alométricamente en relación a la masa corporal, con un crecimiento más ligero de sus extremos proximales que de otras regiones. Los huesos de los miembros posteriores mostraron más de un patrón alométrico. El tarsometatarsus fue negativo; el fémur presentó alometría positiva, con un ancho y profundidad del extremo proximal importantes. Las mediciones del tibiotarso presentaron un crecimiento más rápido, sobre todo la anchura del extremo proximal. Los patrones de crecimiento sugieren estar correlacionados con la ontogenia de la conducta, y reflejan los requisitos musculares para un modo de locomoción diferente.

Unilateral photothrombotic motor cortex lesion-induced hindlimb spastic hemiplegia model in rats / 第二军医大学学报

Objective To examine the feasibility of using photothrombotic unilateral motor cortex lesion for establishing hindlimb spastic hemiplegia model in rats. Methods Twenty SD rats were randomized into 2 groups: rats in group A received erythrosine B injection followed by laser iiradiation, and those in group B received sham operation. Then the rate dependent depression (RDD) of H reflex was employed to measure the spasticity of the plantaris before and 3, 7, 14, 28 days postoperation. H-E staining was used to observed the lesions in the motor cortex. Cholera toxin B subunit was used to retrogradely labll motoneurons in the spinal cord. The number of vesicular glutamine transporter 1 (VGLUT1) boutons on motoneuron soma and dendrite was quantified by immunofluorescence staining and laser confocal microscope scanning. Results Hreflex RDD in the right plantaris muscle was significantly decreased in group A compared with that in group B at 3, 7,14, and 28 days postoperation (P0. 05). The number of VGLUT1 boutons on soma and dendrite in group A was significantly increased compared with that in group B (P<0. 01). H-E staining showed specific lesion in the motor cortex of the brain tissue in group A, but not in group B. Conclusion Unilateral photothrombotic motor cortex lesion is feasible to generate contralateral hindlimb spastic hemiplegia in rats.

Effect of Long-Term Antiorthostatic Suspension in a Murine Model of Acute Lung Injury

OBJECTIVES: Antiorthostatic suspension (AOS) is ground-based model of simulated microgravity. There is still no study about the effect of long-term microgravity on the clinical course of acute lung injury. We evaluated the effect of simulated microgravity using AOS in a murine model of acute lung injury by lipopolysaccharide (LPS). METHODS: Thirty BALB/c mice were used. During 4 weeks, mice were equally allocated to control (free movement), restraint (tail suspended, but hindlimbs not unloaded), and AOS group (hindlimb unloaded). After then, mice got intranasal challenge with LPS (20 mg/kg, 50 μL). We measured: weight gain before and after AOS, the number of inflammatory cells and titers of cytokines (interleukin [IL]-1β, IL-6, IL-10, tumor necrosis factor-α, and interferon-γ) in bronchoalveolar lavage (BAL) fluid, titer of myeloperoxidase (MPO) in serum and lung homogenate, and histopathologic examination of lung tissue. RESULTS: AOS group had significant weight loss compared to control and restraint group (P<0.001). AOS group also showed significantly decreased lymphocytes (P=0.023) compared to control group. In AOS group, titer for IL-1β in BAL fluid was significantly lower than restraint group (P=0.049). Titer for serum MPO was significantly decreased in AOS group compared to restraint group (P=0.004). However, there was no significant difference of MPO titers in lung tissue between groups. Histopathologic examination of lung tissue revealed no significant difference in the degree of pulmonary infiltration between restraint and AOS group. CONCLUSION: In spite of modest anti-inflammatory effect, prolonged AOS caused no significant change in LPS-induced pulmonary inflammation.

Beneficial effect of pentoxifylline into the testis of rats in an experimental model of unilateral hindlimb ischemia/reperfusion injury

The objective of the present study was to investigate the role of pentoxifylline (PTX) on remote testicular injury caused by unilateral hind limb ischemia/reperfusion of rats.

Analysis on Bilateral Hindlimb Mapping in Motor Cortex of the Rat by an Intracortical Microstimulation Method

Intracortical microstimulation (ICMS) is a technique that was developed to derive movement representation of the motor cortex. Although rats are now commonly used in motor mapping studies, the precise characteristics of rat motor map, including symmetry and consistency across animals, and the possibility of repeated stimulation have not yet been established. We performed bilateral hindlimb mapping of motor cortex in six Sprague-Dawley rats using ICMS. ICMS was applied to the left and the right cerebral hemisphere at 0.3 mm intervals vertically and horizontally from the bregma, and any movement of the hindlimbs was noted. The majority (80%+/-11%) of responses were not restricted to a single joint, which occurred simultaneously at two or three hindlimb joints. The size and shape of hindlimb motor cortex was variable among rats, but existed on the convex side of the cerebral hemisphere in all rats. The results did not show symmetry according to specific joints in each rats. Conclusively, the hindlimb representation in the rat motor cortex was conveniently mapped using ICMS, but the characteristics and inter-individual variability suggest that precise individual mapping is needed to clarify motor distribution in rats.

Effect of Mailuoning on an ischemia/reperfusion injury model in the system of simulated in vivo physiological environment for amputated limbs / 中国组织工程研究

BACKGROUND:Reducing the ischemia-reperfusion injury in the system of simulated in vivo physiological environment for amputated limbs, can extend the preservation time and improve the replantation success rate of amputated limb. OBJECTIVE:To investigate the effect of Mailuoning on the ischemia-reperfusion injury in the system of simulated in vivo physiological environment for amputated limbs. METHODS:The left hind legs harvested from 18 healthy adult male Bama mini-pigs were randomly divided into three groups:cold storage group, blood perfusion group, Mailuoning combined blood perfusion group, with six pigs in each group. After the left hind legs of each pig in al groups were amputated and stored at room temperature for 3 hours, the amputated legs were placed at 4 ℃, perfused with blood, or perfused with Mailuoning combined blood. After 6 hours of perfusion, the morphology of amputated limbs was observed under transmission electron microscope. The mRNA levels of apoptosis proteins Caspase3 and inflammatory factor interleukin-1βwere detected by real time fluorescent quantitative RT-PCR.RESULTS AND CONCLUSION:Transmission electron microscopy results showed that, the muscle fibers in blood perfusion group and Mailuoning combined blood perfusion group arranged more orderly and were more complete than cold storage group, the swel ing of mitochondria was lighter. In addition, the condition in Mailuoning combined blood perfusion group was better than in blood perfusion group. RT-PCR results showed that the expression of Caspase3 and interleukin-1βwas increased in al groups;at the same time, the expression level in blood perfusion group and Mailuoning combined blood perfusion group was significantly lower than those in cold storage group. Mailuoning combined blood perfusion group had s lower expression than blood perfusion group. In the system of simulated in vivo physiological environment for amputated limbs, Mailuoning can significantly reduce the ischemia/reperfusion injury of skeletal muscle cells and prolong the preservation time of amputated limbs.

Pathological changes of vascular tissue after rabbit limb replantation with different methods of cryopreservation / 中国组织工程研究

BACKGROUND:The cryopreservation of single tissue has achieved great advancement and is gradual y applied in clinics. However, the cryopreservation of complex tissue is rarely reported. OBJECTIVE:To investigate the morphological change in rabbit limb tissue after replantation through different rewarming methods, find the best rewarming methods of compound textured blood vessels, and provide theoretical basis for the feasibility of limb replantation after long-term cryopreservation. METHODS:Thirty New Zealand white rabbits were randomly divided into control group, slow freezing-slow thawing group, and slow freezing-rapid thawing group. The right posterior limbs of al the rabbits were cut off 1 cm above the knee joint. Except control group, the latter two groups were given limb replantation after thawing, and then the right posterior limb was again cut off after the replanted limbs were survived for 6 hours. For al groups, the histological changes and gross observation in aorta tissue were observed by light microscopy and transmission electron microscope, and the results were analyzed with statistical methods. RESULTS AND CONCLUSION:In the slow freezing-slow thawing, slow freezing-rapid thawing groups, the pathological changes (gross specimen, light microscope, electron microscope) of rabbit limbs 6 hours after replantation were worse than those in control group. Compared with slow freezing-rapid thawing group, better integrity of endothelial cells and less damage of the organel es were found in slow freezing-slow thawing group. Through deep cryogenic freezing-thawing process, rabbit limb blood vessels can maintain the structural integrity after replantation and survived at 6 hours. Slow freezing-slow thawing is better than slow freezing-rapid thawing for the preservation of severed limbs, providing evidences for the long-term survival fol owing a deep cry ogenic treatment after the severed limb replantation.

Rat Model of Hindlimb Ischemia Induced via Embolization with Polyvinyl Alcohol and N-Butyl Cyanoacrylate

OBJECTIVE: To investigate the feasibility of a rat model on hindlimb ischemia induced by embolization from the administration of polyvinyl alcohol (PVA) particles or N-butyl cyanoacrylate (NBCA). MATERIALS AND METHODS: Unilateral hindlimb ischemia was induced by embolization with NBCA (n = 4), PVA (n = 4) or surgical excision (n = 4) in a total of 12 Sprague-Dawley rats. On days 0, 7 and 14, the time-of-flight magnetic resonance angiography (TOF-MRA) and enhanced MRI were obtained as scheduled by using a 3T-MR scanner. The clinical ischemic index, volume change and degree of muscle necrosis observed on the enhanced MRI in the ischemic hindlimb were being compared among three groups using the analysis of variance. Vascular patency on TOF-MRA was evaluated and correlated with angiographic findings when using an inter-rater agreement test. RESULTS: There was a technical success rate of 100% for both the embolization and surgery groups. The clinical ischemic index did not significantly differ. On day 7, the ratios of the muscular infarctions were 0.436, 0.173 and 0 at thigh levels and 0.503, 0.337 and 0 at calf levels for the NBCA, PVA and surgery groups, respectively. In addition, the embolization group presented increased volume and then decreased volume on days 7 and 14, respectively. The surgery group presented a gradual volume decrease. Good correlation was shown between the TOF-MRA and angiographic findings (kappa value of 0.795). CONCLUSION: The examined hindlimb ischemia model using embolization with NBCA and PVA particles in rats is a feasible model for further research, and muscle necrosis was evident as compared with the surgical model.

Effects of limb ischemic preconditioning on intestinal injury during release of hepatic portal occlusion in rats / 中华麻醉学杂志

Objective To evaluate the effects of limb ischemic preconditioning (LIP) on the intestinal injury during release of hepatic portal occlusion (RHPO) in rats.Methods Thirty-six male Sprague-Dawley rats,aged 6-7 weeks,weighing 200-250 g,were randomly divided into 3 groups using a random number table:sham operation group (group S,n =12),RHPO group (n =39) and LIP+ RHPO group (n =20).Hepatic ischemia/ reperfusion was produced by occluding portal vein and hepatic artery for 30 min followed by 6 h reperfusion according to Pringle's method.LIP was produced by tourniquet occlusion of the right femoral artery and vein for 10 min followed by 24 h reperfusion before hepatic ischemia.The animals were sacrificed at 6 h after hepatic portal occlusion was released and the mucous membrane of small intestine was obtained for microscopic examination and for determination of malondialdehyde (MDA) content,superoxide dismutase (SOD) activity,myeloperoxidase (MPO)activity,total antioxidant capacity (T-AOC) and intercellular adhesion molecule-1 (ICAM-1) mRNA and protein expression.The degree of damage to intestinal mucous membrane was scored according to Chiu.Results Compared with group S,Chiu's score and levels of MDA and MPO were significantly increased,SOD activity and TAOC were decreased,and ICAM-1 mRNA and protein expression was up-regulated in group RHPO (P ＜ 0.05 or 0.01).Compared with group RHPO,Chiu's score and levels of MDA and MPO were significantly decreased,SOD activity and T-AOC were increased,and ICAM-1 mRNA expression was down-regulated in group LIP + RHPO (P ＜ 0.05).Conclusion LIP can alleviate the intestinal injury during RHPO in rats by enhancing the antioxidant function and down-regulating the expression of ICAM-1.

Rat Hindlimb Allotransplantation with Short-term Immune Suppressants and Dendritic Cell Pretreatment

Prevention of acute rejection in composite tissue allotransplantation without continuous immunosuppression lacks reports in worldwide literature. Recently dendritic cells (DC) gained considerble attention as antigen presenting cells that are also capable of immunologic tolerance induction. This study assesses the effect of alloantigen-pulsed dendritic cells in induction of survival in a rat hindlimb allograft. We performed hindlimb allotransplantation between donor Sprague-Dawley and recipient Fischer344 rats. Recipient derived dendritic cells were harvested from rat whole blood and cultured with anti-inflammatory cytokine IL-10. Then donor-specific alloantigen pulsed dendritic cells were reinjected into subcutaneous tissue before limb transplantation. Groups: I) untreated (n=6), II) DC injected (n=6), III) Immunosuppressant (FK-506, 2 mg/Kg) injected (n=6), IV) DC and immunouppressant injected (n=6). Graft appearance challenges were assessed postoperatively. Observation of graft appearance, H-E staning, immunohistochemical (IHC) study, and confocal immunofluoreiscece were performed postoperatively. Donor antigen pulsed host dendritic cell combined with short-term immunosuppression showed minimal mononuclear cell infiltration, regulator T cell presence, and could prolong limb allograft survival.