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161.
Svein O. Linge 《Computer methods in biomechanics and biomedical engineering》2013,16(10):1103-1109
Much attention has been devoted to how playground swing amplitudes are built up by swinger techniques, i.e. body actions. However, very little attention has been given to the requirements that such swinger techniques place on the swinger himself. The purpose of this study was to find out whether different swinger techniques yield significantly different maximum torques, endurance and coordinative skills, and also to identify preferable techniques. We modelled the seated swinger as a rigid dumbbell and compared three different techniques. A series of computer simulations were run with each technique, testing the performance with different body rotational speeds, delayed onset of body rotation and different body mass distributions, as swing amplitudes were brought up towards 90°. One technique was found to be extremely sensitive to the timing of body actions, limiting swing amplitudes to 50° and 8° when body action was delayed by 0.03 and 0.3 s, respectively. Two other more robust techniques reached 90° even with the largest of these delays, although more time (and endurance) was needed. However, these two methods also differed with respect to maximum torque and endurance, and none was preferable in both these aspects, being dependent on the swinger goals and abilities. 相似文献
162.
《Biotechnic & histochemistry》2013,88(6):277-305
In order to obtain a better understanding of the “periodic-acid-Schiff” reaction, also known as the “periodic-acid fuchsin-sulfurous-acid” reaction, three types of investigations were carried out1) The Schiff reagent was replaced by other aldehyde reagents: benzidine or o-dianisidine. There was no significant change in the histological distribution and intensity of the reactions occurring after periodic acid oxidation.2) Periodic acid was replaced by another oxidizing agent: lead tetraacetate (dissolved in acetic acid). There was no significant change in the histological distribution of the reactions with the Schiff reagent, but some change in their intensity. It was concluded that 1,2-glycols and a-amino alcohols play the main role in the reactions with both oxidants. The presence of α-hydroxy acids in some types of mucous cells is suggested by the results with lead tetraacetate.Incidently, glycogen and starch are not sufficiently oxidized by lead tetraacetate (in acetic acid) at room temperature to give positive reactions with the Schiff reagent, while cellulose and other periodic-acid-Schiff reactive substances are.3) The staining of films of presumed reactive substances with the periodic-acid-Schiff technic C O the intense reactivity of many polysaccharides, mucopolysaccharides and mucoproteins, but not of ordinary proteins. (Hyaluronic and chondroitin sulfuric acid are, however, not reactive in vitro).In conclusion, the periodic-acid-Schiff technic consists of an oxidation of 1,2-glycols and a-amino alcohols to produce aldehyde groups, which are then stained by the Schiff reagent. The “film test” reveals that these radicals are present in certain polysaccharides, mucopolysaccharides and mucoproteins. 相似文献
163.
《Free radical research》2013,47(2):194-203
Age-dependent declining level of melatonin induces free radical load and thereby deteriorates immune function. However, reports are lacking about age-dependent melatonin membrane receptor (MT1 & MT2) expression, their role in regulation of reactive nitrogen species (RNS) and eventually how they affect immunity of a tropical rodent F. pennanti. We checked MT1R, MT2R and iNOS expression in lymphoid organs of young middle and old aged squirrels. Nitrite and nitrate ion concentration (NOx) in lymphoid organs, testes and plasma, lymphocyte proliferation and IL-2 level was recorded. Age-dependent decrease in MT1 and MT2 receptor expression, lymphocyte proliferation, IL-2 level and increased RNS in lymphoid organs, testes and plasma was observed with decreased circulatory melatonin. Androgen and AR expression was increased in middle-aged while declined in old-aged squirrels. Present study suggests that age associated immunosenescence is consequence of increased RNS which might have important relationship with melatonin membrane receptors in F. pennanti. 相似文献
164.
Takaaki Oteki Sohji Nagase Homare Shimohata Aki Hirayama Atsushi Ueda Hidekatsu Yokoyama 《Free radical research》2013,47(2):154-161
It is well known that oxidative stress is related to the pathogenesis of adriamycin (ADR) nephropathy. However, it is unclear how nitric oxide (NO) is associated with the pathophysiological process after ADR administration. The NO level in a kidney homogenate was assayed by electron paramagnetic resonance (EPR) spectrometry using a direct in vivo NO trapping technique after ADR administration. N-(3-(aminomethyl)benzyl)acetamidine (1400W) was used as a specific, inducible nitric oxide synthase (iNOS) inhibitor. The levels of NO after ADR administration gradually increased for 6 h and then decreased until 24 h after ADR administration. The fractional excretion of Na (FENa) in the urine was elevated in the ADR group on day 1. Pre-treatment of the animals with 1400W attenuated the increase in NO levels despite further elevation of FENa. These findings suggest that iNOS-derived NO does not produce a harmful effect but rather protects the ADR-treated kidney against sodium excretion. 相似文献
165.
Luciana P. Malpiedi César A. Díaz Bibiana B. Nerli Adalberto Pessoa 《Process Biochemistry》2013,48(8):1242-1251
At present, single-chain variable fragments (scFv) of antibodies are considered one of the most important tools in human therapies. Wide applications of antibodies are being exploited in different medical, pharmaceutical and research areas. These molecules maintain the same binding functionality that full length antibodies but possess several advantageous features as quickness to penetrate the tissues, easy manipulation, fast elimination of their immunocomplex and the possibility of being produced in simple expression systems like bacteria and yeast. The increasing demand in antibody based methodologies is driving advances in the production and purification of genetically engineered antibodies and antibody fragments. While advances in expression systems allow the production of high titers of antibodies, there exist some limits imposed by the downstream methodologies which are not efficient enough to ensure their industrialization.The main aim of this review is to highlight the principal characteristics of single-chain variable fragments of antibodies addressing advances and perspectives on scFv purification. 相似文献
166.
Pauline Barbera van de Weert-van Leeuwen Hubertus Gerardus Maria Arets Cornelis Korstiaan van der Ent Jeffrey Matthijn Beekman 《Respiratory research》2013,14(1):32
Regular exercise is positively associated with health. It has also been suggested to exert anti-inflammatory effects. In healthy subjects, a single exercise session results in immune cell activation, which is characterized by production of immune modulatory peptides (e.g. IL-6, IL-8), a leukocytosis and enhanced immune cell functions. Upon cessation of exercise, immune activation is followed by a tolerizing phase, characterized by a reduced responsiveness of immune cells. Regular exercise of moderate intensity and duration has been shown to exert anti-inflammatory effects and is associated with a reduced disease incidence and viral infection susceptibility. Specific exercise programs may therefore be used to modify the course of chronic inflammatory and infectious diseases such as cystic fibrosis (CF).Patients with CF suffer from severe and chronic pulmonary infections and inflammation, leading to obstructive and restrictive pulmonary disease, exercise intolerance and muscle cachexia. Inflammation is characterized by a hyper-inflammatory phenotype. Patients are encouraged to engage in exercise programs to maintain physical fitness, quality of life, pulmonary function and health.In this review, we present an overview of available literature describing the association between regular exercise, inflammation and infection susceptibility and discuss the implications of these observations for prevention and treatment of inflammation and infection susceptibility in patients with CF. 相似文献
167.
《Electromagnetic biology and medicine》2013,32(2):273-282
Electrotherapy with low-level direct current (DC) can induce antitu-mor effects in various tumor models. Applied in combination with certain anticancer drugs, it can significantly increase their effectiveness. It has been suggested that the demonstrated effects of electrotherapy arise from its modification of tumor blood flow. The effect of such treatment on blood perfusion of solid subcutaneous Sa-1 fibrosarcoma tumors in A/J mice was investigated with a 86rubidium extraction technique. Following electrotherapy, the relative tissue perfusion of tumors was decreased by more than 50%. Three days after treatment, partial reperfusion of tumors occurred. The dynamics of the perfusion changes induced by electrotherapy are in agreement with tumor growth dynamics following this procedure. The effect of electrotherapy on the blood supply of tumors may be the major mechanism of antitumor action in our model. Electrotherapy could be useful as an adjuvant local procedure to other treatment modalities that require a hypoxic environment for their effectiveness. 相似文献
168.
Kathrin Schüller Dominik Bühler Nikolaus Plesnila 《Journal of visualized experiments : JoVE》2013,(81)
In this video publication a standardized mouse model of subarachnoid hemorrhage (SAH) is presented. Bleeding is induced by endovascular Circle of Willis perforation (CWp) and proven by intracranial pressure (ICP) monitoring. Thereby a homogenous blood distribution in subarachnoid spaces surrounding the arterial circulation and cerebellar fissures is achieved. Animal physiology is maintained by intubation, mechanical ventilation, and continuous on-line monitoring of various physiological and cardiovascular parameters: body temperature, systemic blood pressure, heart rate, and hemoglobin saturation. Thereby the cerebral perfusion pressure can be tightly monitored resulting in a less variable volume of extravasated blood. This allows a better standardization of endovascular filament perforation in mice and makes the whole model highly reproducible. Thus it is readily available for pharmacological and pathophysiological studies in wild type and genetically altered mice. 相似文献
169.
Kecheng Lei Liwen Zhang Yijing He Hui Sun Weifang Tong Yichun Xu Lingjing Jin 《Bioscience reports》2020,40(12)
Early stage diagnosis of Parkinson’s disease (PD) is challenging without significant motor symptoms. The identification of effective molecular biomarkers as a hematological indication of PD may help improve the diagnostic timelines and accuracy. In the present paper, we analyzed and compared the blood samples of PD and control (CTR) patients to identify the disease-related changes and determine the putative biomarkers for PD diagnosis. Based on the RNA sequencing analysis, differentially expressed genes (DEGs) were identified, and the co-expression network of DEGs was constructed using the weighted gene correlation network analysis (WGCNA). The analysis leads to the identification of 87 genes that were exclusively regulated in the PD group, whereas 66 genes were significantly increased and 21 genes were significantly decreased in contrast with the control group. The results indicate that the core lncRNA–mRNA co-expression network greatly changes the immune response in PD patients. Specifically, the results showed that Prader Willi Angelman Region RNA6 (PWAR6), LINC00861, AC83843.1, IRF family, IFIT family and calcium/calmodulin-dependent protein kinase IV (CaMK4) may play important roles in the immune system of PD. Based on the findings from the present study, future research aims at identifying novel therapeutic strategies for PD. 相似文献
170.
Razieh P. Ahwazi Melika Kiani Meshkat Dinarvand Akram Assali Farnaz S. M. Tekie Rasoul Dinarvand Fatemeh Atyabi 《Journal of cellular physiology》2020,235(3):2049-2059
RNA interference is one of the prosperous approaches for cancer treatment. However, small interfering RNA (siRNA) delivery to cancer cells has been faced with various challenges restricting their clinical application over the decades. Since ROR1 is an onco-embryonic gene overexpressed in many malignancies, suppression of ROR1 by siRNA can potentially fight cancer. Herein, a delivery system for ROR1 siRNA based on HIV-1 TAT peptide-capped gold nanoparticles (GNPs) was developed to treat breast cancer. Besides, we introduced a new feasible method for conjugating the peptide to the nanoparticles. Since the GNPs have high affinity to the sulfur, the findings demonstrated the peptide successfully conjugated to the nanoparticles via Au–S bonds. As positively charged nanoparticles showed high cellular uptake, we could use a low concentration of nanoparticles led to high efficient gene transfection with negligible cytotoxicity that was confirmed by flow cytometry, confocal microscopy, gel retardation, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Following transfection, downregulation of ROR1 and its targeted gene, CCND1, induced apoptosis in cancer cells. In conclusion, the reported capped GNPs could be potentially utilized for delivering negatively charged therapeutic agents in particular genes. 相似文献