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21.
In 2019, the World Health Organization declared 3 billion to be at risk of developing Crimean Congo Hemorrhagic Fever (CCHF). The causative agent of this deadly infection is CCHFV. The data related to the biology and immunology of CCHFV are rather scarce. Due to its indispensable roles in the viral life cycle, NP becomes a logical target for detailed viral immunology studies. In this study, humoral immunity to NP was investigated in CCHF survivors, as well as in immunized mice and rabbits. Abundant antibody response against NP was demonstrated both during natural infection in humans and following experimental immunizations in mice and rabbits. Also, cellular immune responses to recombinant NP (rNP) was detected in multispecies. This study represents the most comprehensive investigation on NP as an inducer of both humoral and cellular immunity in multiple hosts and proves that rNP is an excellent candidate warranting further immunological studies specifically on vaccine investigations.  相似文献   
22.
Background aimsAdipose tissue-derived mesenchymal stromal cells (MSCs) have a higher capacity for proliferation and differentiation compared with other cell lineages. Although distraction osteogenesis is the most important therapy for treating bone defects, this treatment is restricted in many situations. The aim of this study was to examine the therapeutic potential of adipose tissue-derived MSCs and osteoblasts differentiated from adipose tissue-derived MSCs in the treatment of bone defects.MethodsBone defects were produced in the tibias of New Zealand rabbits that had previously undergone adipose tissue extraction. Tibial osteotomy was performed, and a distractor was placed on the right leg of the rabbits. The rabbits were placed in control (group I), stem cell (group II) and osteoblast-differentiated stem cell (group III) treatment groups. The rabbits were sacrificed, and the defect area was evaluated by radiologic, biomechanical and histopathologic tests to examine the therapeutic effects of adipose tissue-derived MSCs.ResultsRadiologic analyses revealed that callus density and the ossification rate increased in group III compared with group I and group II. In biomechanical tests, the highest ossification rate was observed in group III. Histopathologic studies showed that the quality of newly formed bone and the number of cells active in bone formation were significantly higher in group III rabbits compared with group I and group II rabbits.ConclusionsThese data reveal that osteoblasts differentiated from adipose tissue-derived MSCs shorten the consolidation period of distraction osteogenesis. Stem cells could be used as an effective treatment for bone defects.  相似文献   
23.
How small can a macroscopic object be made without losing its intended function? Obviously, the smallest possible size is determined by the size of an atom, but it is not so obvious how many atoms are required to assemble an object so small, and yet that performs the same function as its macroscopic counterpart. In this review, we are concerned with objects of intermediate nature, lying between the microscopic and the macroscopic world. In physics and chemistry literature, this regime in-between is often called mesoscopic, and is known to bear interesting and counterintuitive features. After a brief introduction to the concept of mesoscopic systems from the perspective of physics, we discuss the functional aspects of mesoscopic architectures in cell biology, and supramolecular chemistry through many examples from the literature. We argue that the biochemistry of the cell is largely regulated by mesoscopic functional architectures; however, the significance of mesoscopic phenomena seems to be quite underappreciated in biological sciences. With this motivation, one of our main purposes here is to emphasize the critical role that mesoscopic structures play in cell biology and biochemistry.  相似文献   
24.
Myocardial infarction (MI), which is the most important manifestation of coronary artery disease, is the leading cause of morbidity and mortality in the world. Glutathione S transferases (GSTs) are enzymes responsible for the metabolism of numerous xenobiotics and are known to be polymorphic in humans. We investigated the association between the GSTM1 and GSTT1 gene polymorphisms and MI. The study consists of 296 healthy controls and 324 consecutive patients who had undergone coronary angiography for suspicion of coronary artery disease and with a past history of myocardial infarction. DNA was extracted from whole blood of patient and control. GSTM1 and GSTT1 gene polymorphisms were examined using multiplex PCR. We found that the null GSTM1 was associated with protective effect on MI, although this increase was not significant for GSTM1 (p < 0.054). However, GSTT1 genotype was associated with an increase in the risk of developing MI. In addition to after adjusting other all coronary risk factors, the interactive effect of GSTT1 null genotype remained statistically significant (p < 0.001) for MI disease but GSTM1 null genotype was not statistically significant. Patients, who smoke having the null genotypes of GSTM1, were at a higher risk for developing MI (p < 0.001, OR = 0.41, 95 % CI = 0.240–0.207). There was an effect of interaction of GSTM1 null genotype and smoking on MI development between patient and control groups (p < 0.001). Our results showed that individuals with the null genotypes for GSTM1 had protective effect, while GSTT1 was at a higher risk for MI disease. In addition, there was additional effects of smoking when smoking and non-smoking groups were compared.  相似文献   
25.
在嗜盐菌长期的盐适应或短期的盐胁迫过程中,甘氨酸甜菜碱(又名三甲基甘氨酸,N,N,N-trimethylglycine)发挥着极为重要的作用。甘氨酸甜菜碱在嗜盐菌中的生物合成有2种途径:胆碱氧化途径和甘氨酸甲基化途径。前者以胆碱为底物,由胆碱脱氢酶(cholinedehydrogenase,BetA)和甜菜碱乙醛脱氢酶(betaine aldehyde dehydrogenase,BetB)经2次氧化生成甜菜碱;后者以甘氨酸作为底物,由甘氨酸肌醇甲基转移酶(glycine sarcosine N-methyltransferase,GSMT)和肌氨酸二甲基甘氨酸甲基转移酶(sarcosine dimethylglycine N-methyltransferase,SDMT)经3次N-甲基化生成甜菜碱。目前在JGI-IMG和EZBioCloud数据库中公布了134株嗜盐菌标准菌株的全基因组序列。其中,约56.0%的嗜盐细菌和约39.6%的嗜盐古菌拥有胆碱氧化途径所需的2个基因;约9.7%的嗜盐细菌和约0.7%的嗜盐古菌携带甲基化途径所需的2个基因。其中,8株嗜盐细菌同时拥有胆碱氧化途径和甘氨酸甲基化途径所需的全部基因。甘氨酸甜菜碱生物合成基因在典型微生物菌株或经济作物中的表达可以提高其耐盐抗逆能力,这种独特的优势已经引起科学家们强烈的兴趣,相信未来,嗜盐菌中甘氨酸甜菜碱生物合成领域内的科学理论和技术应用会有重大的突破。  相似文献   
26.
Blood-brain barrier (BBB) leakage plays a role in the pathogenesis of many pathological states of the brain including ischemia and some neurodegenerative disorders. In recent years, erythropoietin (EPO) has been shown to exert neuroprotection in many pathological conditions including ischemia in the brain. This study aimed to investigate the effects of EPO on BBB integrity, infarct size and lipid peroxidation following global brain ischemia/reperfusion in rats. Wistar male rats were divided into four groups (each group n=8); Group I; control group (sham-operated), Group II; ischemia/reperfusion group, Group III; EPO treated group (24 h before decapitation--000 U/kg r-Hu EPO i.p.), Group IV; EPO+ ischemia/reperfusion group (24 h before ischemia/reperfusion--3000 U/kg r-Hu EPO i.p.). Global brain ischemia was produced by the combination of bilateral common carotid arteries occlusion and hemorrhagic hypotension. Macroscopical and spectrophotometrical measurement of Evans Blue (EB) leakage was observed for BBB integrity. Infarct size was calculated based on 2,3,5-triphenyltetrazolium chloride (TTC) staining. Lipid peroxidation in the brain tissue was determined as the concentration of thiobarbituric acid-reactive substances (TBARS) for each group. Ischemic insult caused bilateral and regional BBB breakdown (hippocampus, cortex, corpus striatum, midbrain, brain stem and thalamus). EPO pretreatment reduced BBB disruption, infarct size and lipid peroxide levels in brain tissue with 20 min ischemia and 20 min reperfusion. These results suggest that EPO plays an important role in protecting against brain ischemia/reperfusion through inhibiting lipid peroxidation and decreasing BBB disruption.  相似文献   
27.
A recombinant carotenoid cleavage dioxygenase from Vitis vinifera L. was produced by Escherichia coli as a fusion with the glutathione-S-transferase (GST) protein under different bacterial growth conditions. The enzyme production was monitored by a GST assay. Addition of Triton X-100 prior to bacterial cell disruption doubled the release of soluble protein. A simple spectrophotometric enzyme assay was developed to measure carotenoid cleavage activity using lutein as substrate. Enzyme activity showed a 26-fold increase with the addition of 10% (v/v) acetone in the reaction mixture.  相似文献   
28.
Colorectal cancer (CRC) develops as a multi-step process which results from gradual accumulation of mutations in proto-oncogenes, tumor suppressor, and DNA repair genes. Mortality rate of CRC is very high. Therefore, development of alternative diagnostic methods which can be used in the early diagnosis is crucial. ATP2B4 gene encodes one of the four isoforms of p-type ATPase PMCA enzyme and bears critical importance in maintaining the balance of intracellular calcium homeostasis by providing the export of calcium ions out of the cell. ATP5B encodes a subunit of the mitochondrial ATP synthase which is an f-type ATPase. In this study, the relationship between ATP2B4 and ATP5B genes and CRC regarding gene expression was investigated. Study groups were constructed from a number of 50 patients (25 males, 25 females) with the mean age of 55.68 ± 9.4 and the gene expression levels in the healthy and cancerous tissues of the patients were compared by using semi-quantitative PCR and Real-Time PCR methods. As a result, in patients with rectum tumors, there was a significant relationship between ATP2B4 gene expression and the tumor location and in patients younger than 45 years, ATP5B gene expressions were detected significantly higher in tumor tissues by using RT-PCR. However, no significant relationship was detected in terms of expression differences of ATP2B4 and ATP5B genes between cancerous and healthy tissues of the CRC patients. ATP2B4 and ATP5B genes might have indirect associations in CRC pathogenesis and the investigation of their interactions with DNA repair and other related genes may help in understanding of CRC formation.  相似文献   
29.
30.
A potential Carotenoid Cleavage Dioxygenase (CCD) gene was identified among a Vitis vinifera L. EST collection and a full-length cDNA (VvCCD1) was isolated. Recombinant expression of VvCCD1 confirmed that the gene encoded a functional CCD. Experimental evidence was obtained that VvCCD1 cleaves zeaxanthin symmetrically yielding 3-hydroxy-beta-ionone, a C(13)-norisoprenoidic compound, and a C(14)-dialdehyde. Expression of the gene was studied by real-time PCR at different developmental stages of grape berries from Muscat of Alexandria and Shiraz cultivars. A significant induction of the gene expression approaching véraison was observed in both cultivars. In parallel, the C(13)-norisoprenoid level increased from véraison to maturity in both cultivars.  相似文献   
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