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91.
92.

Objective

Musculodegenerative diseases threaten the life of many patients in the world. Since drug administration is not efficient in regeneration of damaged tissues, stem cell therapy is considered as a good strategy to restore the lost cells. Since the efficiency of myogenic differentiation potential of human Chorion- derived Mesenchymal Stem Cells (C-MSCs) has not been addressed so far; we set out to evaluate myogenic differentiation property of these cells in comparison with Umbilical Cord Blood- derived Mesenchymal Stem Cells (UCB-MSCs) in the presence of 5-azacytidine.

Materials & methods

To do that, neonate placenta Umbilical Cord Blood were transferred to the lab. After characterization of the isolated cells using flowcytometry and multilineage differentiation capacity, the obtained Mesenchymal Stem Cells were cultured in DMEM/F12 supplemented with 2% FBS and 10 μM of 5-azacytidine to induce myogenic differentiation. Real-time PCR and immunocytochemistry were used to assess the myogenic properties of the cells.

Results

Our data showed that C-MSCs and UCB-MSCs were spindle shape in morphology. They were positive for CD90, CD73 and CD44 antigens, and negative for hematopoietic markers. They also differentiated into osteoblast and adipoblast lineages. Real-time PCR results showed that the cells could express MyoD, desmin and α-MHC at the end of the first week (P < 0.05). No significant upregulation was detected in the expression of GATA-4 in both groups. Immunocytochemical staining revealed the expression of Desmin, cTnT and α-MHC.

Conclusions

Results showed that these cells are potent to differentiate into myoblast- like cells. An upregulation in the expression of some myogenic markers (desmin, α- MHC) was observed in C-MSCs in comparison with UCB-MSCs.  相似文献   
93.
94.
Collective motion and cannibalism in locust migratory bands   总被引:2,自引:0,他引:2  
Plagues of mass migrating insects such as locusts are estimated to affect the livelihood of one in ten people on the planet [1]. Identification of generalities in the mechanisms underlying these mass movements will enhance our understanding of animal migration and collective behavior while potentially contributing to pest-management efforts. We provide evidence that coordinated mass migration in juvenile desert locusts (Schistocerca gregaria) is influenced strongly by cannibalistic interactions. Individuals in marching bands tend to bite others but risk being bitten themselves. Reduction of individuals' capacity to detect the approach of others from behind through abdominal denervation (1) decreases their probability to start moving, (2) dramatically reduces the mean proportion of moving individuals in groups, and (3) significantly increases cannibalism. Similarly, occlusion of the rear visual field inhibits individuals' propensity to march. Abdomen denervation did not influence the behavior of isolated locusts. When within groups, abdominal biting and the sight of others approaching from behind triggers movement, creating an autocatalytic feedback that results in directed mass migration. This "forced march" driven by cannibalistic interactions suggests that we need to reassess our view of both the selection pressure and mechanism that can result in the coordinated motion of such large insect groups.  相似文献   
95.
We report DNA construction, baculovirus expression, and partial characterization of a minienzyme form of the human matrix metalloproteinase-9 (MMP-9). The MMP-9 minienzyme gene construct consisting of the pre, pro, and catalytic domains of the MMP-9 was introduced into Sf9 insect cells using a baculovirus expression system. The expression of the recombinant MMP-9 minienzyme was estimated to be approximately 0.8 mg/L of cell medium. The recombinant protein was purified using a single-step gelatin-Sepharose affinity column and yielded a highly stable and active minienzyme with gelatinolytic activity. Moreover, two interesting findings related to MMP-9 interactions with heparin and TIMP-1 resulted from our studies. First, the pro and catalytic domains of the human MMP-9 are not sufficient for heparin affinity. Second, in contrast to the prevailing consensus, TIMP-1 blockade of the enzymatic activity of MMP-9 does not require prior binding to the C-terminus of its MMP-9 protein substrate.  相似文献   
96.
Age-related macular degeneration (AMD) is the most common cause of incurable blindness in the developed world. Little is known about the pathogenesis of this condition, but deposits in Bruch's membrane and immediately beneath the retinal pigment epithelium are frequent findings associated with this disease. Within these deposits, molecular assemblies with an approximately 100-nm axial periodicity are seen. Two types of assembly are present: one exhibiting transverse double bands of protein density that are 30nm apart and repeat axially every approximately 100nm; the other with transverse double bands of protein density, 30nm apart and repeating axially every approximately 50nm. In this second type of assembly, more prominent pairs of bands alternate with less prominent ones. By comparison with analogous aggregates found in the vitreous of a patient with a full-thickness macular hole, collagen VI was singled out as the most probable protein constituent of the AMD aggregates. Possible models for the aggregation patterns of these assemblies are discussed in terms of collagen VI dimers and tetramers. Understanding the structure and chemical composition of the assemblies within the AMD basal deposits may prove of great help in understanding the pathophysiology of AMD itself.  相似文献   
97.
Extensively produced by members of the genus Streptomyces, piericidins are a large family of microbial metabolites, which consist of main skeleton of 4-pyridinol with methylated polyketide side chain. Nonetheless, these metabolites show differences in their bioactive potentials against micro-organisms, insects and tumour cells. Due to its close structural similarity with coenzyme Q, piericidins also possess an inhibitory activity against NADH dehydrogenase as well as Photosystem II. This review studied the latest research progress of piericidins, covering the chemical structure and physical properties of newly identified members, bioactivities, biosynthetic pathway with gene clusters and future prospect. With the increasing incidence of drug-resistant human pathogen strains and cancers, this review aimed to provide clues for the development of either new potential antibiotics or anti-tumour agents.  相似文献   
98.
Khaksar  Sepideh  Salimi  Mona  Zeinoddini  Hadi  Naderi  Nima 《Neurochemical research》2022,47(5):1226-1242

In this research, the involvement of CB1 and TRPV1 receptors in the possible protective effects of anandamide were investigated in the kindling model of epilepsy. The basolateral amygdala of the rat brain was chosen to put stimulating electrodes. Semi-rapid kindling was induced by a repetitive sub-threshold stimulation for 5–9 consecutive days. There were seven groups, six of which were kindled and used for drug testing by intracerebroventricular (i.c.v.) microinjection. (i) Sham, (ii) control group received vehicles, (iii) anandamide (AEA; 100 ng/rat), (iv) capsazepine (TRPV1 antagonist; 100 ng/rat), (v) AM251 (CB1 antagonist; 100 ng/rat), (vi) AM251?+?anandamide, and (vii) capsazepine?+?anandamide. The after-discharge duration, seizure duration, and stage five duration were measured in rats. Moreover, the expressions of the extracellular signal-regulated kinase (ERK) and the cAMP responsive element binding (CREB) proteins in the hippocampus were also studied. The anandamide-treated group showed a significant decrease in seizure scores, while no change was shown in seizure scores in the capsazepine- and AM251-treated groups compared with the control group. Co-administrations of either capsazepine?+?AEA or AM251?+?AEA attenuated the protective effect of AEA against seizure. Furthermore, the group received AEA showed a decrease in the expressions of CREB and p-CREB possibly through the activation of the CB1 and TRPV1 receptors. Activation of CB1 and TRPV1 receptors might be involved in AEA anticonvulsant effect in kindling model of epilepsy. This effect could be due to suppression of CREB phosphorylation in hippocampal neurons.

  相似文献   
99.
International Journal of Peptide Research and Therapeutics - The Nuclear Mitotic Apparatus protein (NuMA) is a nuclear protein that plays critical role in the mitosis as an organizer of the mitotic...  相似文献   
100.

Introduction

Neuroblastoma is a malignant pediatric cancer derived from neural crest cells. It is characterized by a generalized reduction of mitochondrial oxidative phosphorylation. The goal of the present study was to investigate the effects of calorie restriction and ketogenic diet on neuroblastoma tumor growth and monitor potential adaptive mechanisms of the cancer’s oxidative phosphorylation system.

Methods

Xenografts were established in CD-1 nude mice by subcutaneous injection of two neuroblastoma cell lines having distinct genetic characteristics and therapeutic sensitivity [SH-SY5Y and SK-N-BE(2)]. Mice were randomized to four treatment groups receiving standard diet, calorie-restricted standard diet, long chain fatty acid based ketogenic diet or calorie-restricted ketogenic diet. Tumor growth, survival, metabolic parameters and weight of the mice were monitored. Cancer tissue was evaluated for diet-induced changes of proliferation indices and multiple oxidative phosphorylation system parameters (respiratory chain enzyme activities, western blot analysis, immunohistochemistry and mitochondrial DNA content).

Results

Ketogenic diet and/or calorie restriction significantly reduced tumor growth and prolonged survival in the xenograft model. Neuroblastoma growth reduction correlated with decreased blood glucose concentrations and was characterized by a significant decrease in Ki-67 and phospho-histone H3 levels in the diet groups with low tumor growth. As in human tumor tissue, neuroblastoma xenografts showed distinctly low mitochondrial complex II activity in combination with a generalized low level of mitochondrial oxidative phosphorylation, validating the tumor model. Neuroblastoma showed no ability to adapt its mitochondrial oxidative phosphorylation activity to the change in nutrient supply induced by dietary intervention.

Conclusions

Our data suggest that targeting the metabolic characteristics of neuroblastoma could open a new front in supporting standard therapy regimens. Therefore, we propose that a ketogenic diet and/or calorie restriction should be further evaluated as a possible adjuvant therapy for patients undergoing treatment for neuroblastoma.  相似文献   
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