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161.
The aim of this study was to evaluate the possible protective effects of caffeic acid phenethyl ester (CAPE) against cholestatic
oxidative stress and liver damage in the common bile duct ligated rats. A total of 18 male Sprague–Dawley rats were divided
into three groups: control, bile duct ligation (BDL) and BDL + received CAPE; each group contain 6 animals. The rats in CAPE
treated groups were given CAPE (10 μmol/kg) once a day intraperitoneally (i.p) for 2 weeks starting just after BDL operation.
The changes demonstrating the bile duct proliferation and fibrosis in expanded portal tracts include the extension of proliferated
bile ducts into lobules, inflammatory cell infiltration into the widened portal areas were observed in BDL group. Treatment
of BDL with CAPE attenuated alterations in liver histology. The proliferating cell nuclear antigen and the activity of TUNEL
in the BDL were observed to be reduced with the QE treatment. The application of BDL clearly increased the tissue hydroxyproline
(HP) content, malondialdehyde (MDA) levels and decreased the antioxidant enzyme (superoxide dismutase (SOD), glutathione peroxidase
(GPx)) activities. CAPE treatment significantly decreased the elevated tissue HP content, and MDA levels and raised the reduced
of SOD, and GPx enzymes in the tissues. The data indicate that CAPE attenuates BDL-induced cholestatic liver injury, bile
duct proliferation, and fibrosis. The hepatoprotective effect of CAPE is associated with antioxidative potential. 相似文献
162.
Bone regeneration and stem cells 总被引:1,自引:0,他引:1
Arvidson K Abdallah BM Applegate LA Baldini N Cenni E Gomez-Barrena E Granchi D Kassem M Konttinen YT Mustafa K Pioletti DP Sillat T Finne-Wistrand A 《Journal of cellular and molecular medicine》2011,15(4):718-746
This invited review covers research areas of central importance for orthopaedic and maxillofacial bone tissue repair, including normal fracture healing and healing problems, biomaterial scaffolds for tissue engineering, mesenchymal and foetal stem cells, effects of sex steroids on mesenchymal stem cells, use of platelet-rich plasma for tissue repair, osteogenesis and its molecular markers. A variety of cells in addition to stem cells, as well as advances in materials science to meet specific requirements for bone and soft tissue regeneration by addition of bioactive molecules, are discussed. 相似文献
163.
Cysteine is a nonessential aminoacid, meaning that cysteine can be made in the human body. It is one of the few amino acids that contain sulfur. This allows cysteine to bond in a special way and maintain the structures of proteins in the body. Cysteine strengthens the protective lining of the stomach and intestines, which may help prevent damage caused by aspirin and similar drugs. In addition, cysteine may play an important role in the communication between immune system cells. In this study, glassy carbon electrodes modified with mercury (Hg) were used as working electrode. Mercury thin film on glassy carbon electrode was deposited by holding the electrode potential at -0.7 V; the measurement period for the coating process was 2 minutes. pH and temperature effects on the electrode response were carried out by working at different pHs and temperatures. The calibration graph for cysteine was drawn in the range of 5-120 μM cysteine. Repeatability and interferences studies were investigated. GSH had an interference effect of about 13% of cysteine response. Finally, the sensor was applied to real samples for cysteine determination and the method was validated by Ellman's reagent. 相似文献
164.
Bicer M Akil M Sivrikaya A Kara E Baltaci AK Mogulkoc R 《Journal of physiology and biochemistry》2011,67(4):511-517
The present study aims to examine the effect of supplementation of zinc on the distribution of various elements in the sera
of diabetic rats subjected to an acute swimming exercise. A total of 80 Sprague–Dawley-type adult male rats were equally allocated
to one of eight groups: Group 1, general; Group 2, zinc-supplemented; Group 3, zinc-supplemented diabetic; Group 4, swimming
control; Group 5, zinc-supplemented swimming; Group 6, zinc-supplemented diabetic swimming; Group 7, diabetic swimming; and
Group 8, diabetes. The rats were injected with 40 mg/kg/day subcutaneous streptozotocin (STZ) twice, with a 24-h interval
between two injections. Zinc was supplemented at a dose of 6 mg/kg/day (ip) for 4 weeks. Blood samples were collected at the
end of the 4-week study, and serum levels of lead, cobalt, molybdenum, chrome, sulfur, magnesium, manganese, sodium, potassium,
phosphorus, copper, iron, calcium, zinc, and selenium (mg/L) were determined with atomic emission. The lowest molybdenum,
chrome, copper, iron, potassium, magnesium, sodium, phosphorus, lead, selenium, and zinc values were obtained in Group 7 and
8. These same parameters were higher in the swimming exercise group (Group 4), relative to all other groups. The values in
zinc-supplemented groups were found lower than the values in Group 4, but higher than those in Group 6 and 7. The results
obtained from the study demonstrate that acute swimming exercise and diabetes affect the distribution of various elements
in the serum, while zinc supplementation can prevent the negative conditions associated with both exercise and diabetes. 相似文献
165.
Yilmaz N Vural H Yilmaz M Sutcu R Sirmali R Hicyilmaz H Delibas N 《Journal of receptor and signal transduction research》2011,31(3):214-219
Calorie restriction (CR) has attracted increased interest since CR enhances lifespan and alters age-related decline in hippocampal-dependent cognitive functions. Obesity is associated with poor neurocognitive outcome including impaired hippocampal synaptic plasticity and cognitive abilities such as learning and memory. N-Methyl-D-aspartate receptors (NMDARs) are linked to hippocampal-dependent learning and memory, which may be stabilized by CR. In the present study, we aimed to establish the effects of CR on NMDARs in CA1 region of hippocampus in obese and non-obese rats. In addition, malondialdehyde (MDA) levels were determined as a marker for lipid peroxidation (LPO) in hippocampus. Four groups were constituted as control group (C, n?=?9), obese group (OB, n?=?10), obese calorie-restricted group (OCR, n?=?9), and non-obese calorie-restricted group (NCR, n?=?10). OCR and NCR were fed with a 60% CR diet for 10 weeks. After 10 weeks of CR, the MDA levels significantly decreased in the calorie-restricted groups. Obesity caused significant decreases in NR2A and NR2B subunit expressions in the hippocampus. The hippocampal NR2A and NR2B levels significantly increased in the OCR group compared with the OB group (P?0.05). In contrast, the hippocampal NR2A and NR2B levels significantly decreased in the NCR group compared with the C group (P?0.05). Oxidative stress can be prevented by CR, and these data may provide a molecular and cellular mechanism by which CR may regulate NMDAR-mediated response against obesity-induced changes in the hippocampus. 相似文献
166.
Aslan M Yüksel P Polat E Cakan H Ergin S Öner YA Zengin K Arıkan S Saribas S Torun MM Kocazeybek B 《The new microbiologica》2011,34(2):173-177
Cystic echinococcosis (CE) is the larval cystic stage (called echinococcal cysts) of a small taeniid-type tapeworm (Echinococcus granulosus). Carnivores such as dogs are usually definitive hosts. Intermediate hosts are typically herbivores such as sheep and cattle. CE can be detected using various imaging techniques such as ultrasonography or radiology. Moreover the primary diagnosis has to be confirmed by serological tests since the clinical signs of the disease are non-specific. This study examined the antigenic band patterns useful for serologic diagnosis of hydatidosis. We also report on the post-operative evolution of patients treated for this disease and also determined the diagnostic performance of Western blot IgG kit. Twenty-five (16 females and 9 males) non-operated patients with hydatid cysts (NOP) and 33 (21 females and 12 males) operated patients with hydatid cysts (OP) were included as study group and 22 healthy individuals (14 females and 8 males) with no known chronic diseases were included as a control group. The ages of the patients and control group individuals were between 16-83 years. Patient and control groups were matched for age and sex. Cyst hydatid IgG antibodies were detected in the sera from all patient groups but no antibodies were found in the sera from the control group using ELISA IgG method. Twenty-three (92%) non-operated patients and 18 (54.5%) operated patients exhibited positive results when Western blot IgG kit was used. The P7 band pattern was detected in the sera from all operated and non-operated patients. Twenty-seven of these positive cases had p7 and (p7+p16/18), (p7+p24/26) or (p7+p16/18+p24/26). No antibodies against p7, p16/18 ve p24/26 band patterns were seen in sera from the control group A statistically significant difference was detected between operated and nonoperated patients for Western blot positivity.(p<0.01). p: 0.018- X2=5,604- OR: 0.176- 95% CI: 0.037- 0.841. The sensitivity, specificity, positive prediction and negative prediction values of Echinococcus granulosus Western blot kit for 25 cases with CE and 22 healthy controls were calculated as 92%, 100%, 100% and 91.7%, respectively. In conclusion, we suggest that monitoring p7 in all non-operated patients may be useful to determine the efficiacy of medical treatment and that monitoring p7 antibodies using serological and Western blot methods in operated patients may be useful for the screening of post-operative evolution in patients with hydatid cyst. 相似文献
167.
In this work, modified carboxymethylcellulose (CMC) was used as a new support material for production of ethanol. Crosslinked
graft copolymers of CMC with N-vinyl-2-pyrrolidone (N-VP) were prepared in different grafting yields. The beads material was characterized by means of fourier transform infrared
spectroscopy (FT-IR), differential scanning calorimetry (DSC), scanning electron microscope (SEM) and swelling experiment.
Saccharomyces cerevisiae was immobilized using entrapment method in the graft copolymers of carboxymethylcellulose-g-poly(N-vinyl-2-pyrrolidone) (CMC-g-PVP)
for ethanol fermentation. The effects of grafting yield, initial glucose concentration and crosslinker concentration on the
yield of ethanol process were investigated. Reusability of the immobilized yeasts was investigated and found that the materials
can be used four times without losing their activity. Ethanol production increased to 59.3 g/L from 46.4 g/L when percentage
of N-VP in the graft copolymer was increased. The highest ethanol productivity was found to be 1.75–2.25 g/L h. Fermentation time
decreased with the decreasing of crosslinker concentration. The results suggest that the proposed method for immobilization
of Saccharomyces cerevisiae has potential in industrial applications for ethanol process. 相似文献
168.
Methods described in this paper are confined to in vitro dedifferentiated plant cell suspension cultures, which are convenient for the large-scale production of fine chemicals in bioreactors and for the study of cellular and molecular processes, as they offer the advantages of a simplified model system for the study of plants when compared with plants themselves or differentiated plant tissue cultures. The commonly used methods of initiation of a callus from a plant and subsequent steps from callus to cell suspension culture are presented in the protocol. This is followed by three different techniques for subculturing (by weighing cells, pipetting and pouring cell suspension) and four methods for growth measurement (fresh- and dry-weight cells, dissimilation curve and cell volume after sedimentation). The advantages and disadvantages of the methods are discussed. Finally, we provide a two-step (controlled rate) freezing technique also known as the slow (equilibrium) freezing method for long-term storage, which has been applied successfully to a wide range of plant cell suspension cultures. 相似文献
169.
170.
Mustafa Karakse 《Plant Diversity》2022,44(6):577
This study aims to identify medicinal plants traditionally used to treat diseases by local people living in Güce district, north-eastern Turkey. The study was carried out between 2018 and 2021 using a two-part semi-structured, open-ended questionnaire with 165 local people. Data were analysed using use-report, frequency of citation, and informant consensus factor. Informants identified 128 vascular medicinal plant taxa belonging to 54 families and 106 genera. The most common plant taxa belong to Rosaceae (16 taxa/12.5%), Asteraceae (12 taxa/9.4%), and Lamiaceae (9 taxa/7%) families. The most frequently used preparation method reported was decoction (39.8%); the most commonly utilized plant parts were leaves (40.3%). Statistical analysis reveals that women in Güce district (df = 163, p = 0.043 < 0.05) possess the most traditional knowledge. The highest frequency of citation (61) and use report (92) were recorded for Tilia rubra subsp. caucasica, and the highest informant consensus factors were cited for respiratory system disorders (0.86), digestive system disorders (0.73), and skin disorders (0.71). This study reported nine plant taxa as medicinal plants for the first time, and documented a total of 293 new therapeutic uses. However, the study indicates that the transfer of traditional knowledge to future generations is limited (F = 3.355, p = 0.020). Action should be taken as soon as possible to preserve existing traditional knowledge and to ensure its transfer to future generations. 相似文献