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181.
AIMS: The present study was designed to determine the individual and combined effects of acidified sodium chlorite (ASC, 0.1%, 24 +/- 1 degrees C), cetylpyridinium chloride (CPC, 0.5%, 24 +/- 1 degrees C) and hot water (HW, 93 +/- 1 degrees C) treatments on the survival of Listeria monocytogenes and Staphylococcus aureus. METHODS AND RESULTS: Beef samples inoculated with L. monocytogenes and S. aureus were treated with nine different applications singly or in combination. Treatment groups comprised (i) untreated control; (ii) sterile tap water; (iii) 0.1% ASC; (iv) 0.5% CPC; (v) HW; (vi) HW followed by 0.1% ASC; (vii) HW followed by 0.5% CPC; (viii) 0.1% ASC followed by HW; (ix) 0.5% CPC followed by HW. Compared with the untreated control group, the reductions in L. monocytogenes populations were 1.14-2.31 log CFU g(-1), while the reductions in S. aureus populations were 0.83-2.74 log CFU g(-1) on day 0. CONCLUSION: The reduction effect that occurred after combined treatment with ASC followed by HW, HW followed by ASC, CPC followed by HW and HW followed by CPC was found to be significantly greater (P < 0.05) than after treatment with ASC and CPC alone on days 0, 2 and 4 of storage. SIGNIFICANCE AND IMPACT OF THE STUDY: ASC, CPC and HW treatments can be used to reduce L. monocytogenes and S. aureus, which would provide an additional measure of safety on the production line.  相似文献   
182.
Osteoarthritis (OA), the most prevalent joint disease, is a major cause of disability worldwide. Growth hormone (GH) has been suggested to play significant roles in maintaining articular chondrocyte function and ultimately articular cartilage (AC) homeostasis. In humans, the age‐associated decline in GH levels was hypothesized to play a role in the etiology of OA. We studied the impact of adult‐onset isolated GH deficiency (AOiGHD) on the life span and skeletal integrity including the AC, in 23‐ to 30‐month‐old male and female mice on C57/BL6 genetic background. Reductions in GH during adulthood were associated with extended life span and reductions in body temperature in female mice only. However, end‐of‐life pathology revealed high levels of lymphomas in both sexes, independent of GH status. Skeletal characterization revealed increases in OA severity in AOiGHD mice, evidenced by AC degradation in both femur and tibia, and significantly increased osteophyte formation in AOiGHD females. AOiGHD males showed significant increases in the thickness of the synovial lining cell layer that was associated with increased markers of inflammation (IL‐6, iNOS). Furthermore, male AOiGHD showed significant increases in matrix metalloproteinase‐13 (MMP‐13), p16, and β‐galactosidase immunoreactivity in the AC as compared to controls, indicating increased cell senescence. In conclusion, while the life span of AOiGHD females increased, their health span was compromised by high‐grade lymphomas and the development of severe OA. In contrast, AOiGHD males, which did not show extended life span, showed an overall low grade of lymphomas but exhibited significantly decreased health span, evidenced by increased OA severity.  相似文献   
183.
Objectives: acute coronary syndrome (ACS) is defined as an inflammatory disease associated with development of atherosclerosis and instability. IL-1 is a candidate inflammatory cytokine that is thought to trigger ACS. The purpose of this study was to determine the relationship between IL-1 gene family polymorphisms (IL-1RN, IL-1B in positions -511 and +3953) and ACS in the Turkish population. Methods: a total of 381 people participated in the study, with 117 control subjects and 264 ACS patients. Of the 264 ACS patients, 112 were diagnosed with stable angina pectoris (SAP) and 152 were diagnosed with unstable angina pectoris (USAP). The polymerase chain reaction (PCR) was used to determine the genotype of IL-1RN. The genotypes of IL-1B (-511 and +3953) were determined by PCR, followed by restriction enzyme digestion of the PCR products. Results: there were no significant differences in both IL-1RN, IL-1B (-511 and +3953) genotype distributions and IL-1RN allele frequencies between ACS patients and the control subjects. In addition, no association was observed in the allele frequency of IL-1B (-511 and +3953) between ACS patients and controls (p = 0.113 and p = 0.859, respectively), or between SAP patients and controls (p = 0.575 and p = 0.359, respectively). However, IL-1B allele 1 (C) (-511) polymorphism in USAP patients was found to be significantly different from that of control subjects (p = 0.041, OR: 2.01; 95% CI: 1.985-3.933). A significant difference was also observed between USAP and SAP patients for IL-1B (+3953) allele 1 (C) polymorphism; (p = 0.043, OR: 1.522; 95% CI: 1.012-2.88). Conclusion: these results show that IL-1RN gene polymorphism has no association with ACS. However, the allele 1 (C) of IL-1B (-511) may be a risk factor for susceptibility to USAP in the Turkish population.  相似文献   
184.
Many of the genes for lipopolysaccharide (LPS) biosynthesis in Haemophilus influenzae are phase variable. The mechanism of this variable expression involves slippage of tetranucleotide repeats located within the reading frame of these genes. Based on this, we hypothesized that tetranucleotide repeat sequences might be used to identify as yet unrecognized LPS biosynthetic genes. Synthetic oligonucleotides (20 bases), representing all previously reported LPS-related tetranucleotide repeat sequences in H. influenzae, were used to probe a collection of 25 genetically and epidemiologically diverse strains of non-typeable H. influenzae. A novel gene identified through this strategy was a homologue of oafA, a putative O-antigen LPS acetylase of Salmonella typhimurium, that was present in all 25 non-typeable H. influenzae, 19 of which contained multiple copies of the tetranucleotide 5'-GCAA. Using lacZ fusions, we showed that these tetranucleotide repeats could mediate phase variation of this gene. Structural analysis of LPS showed that a major site of acetylation was the distal heptose (HepIII) of the LPS inner-core. An oafA deletion mutant showed absence of O-acetylation of HepIII. When compared with wild type, oafA mutants displayed increased susceptibility to complement-mediated killing by human serum, evidence that O-acetylation of LPS facilitates resistance to host immune clearance mechanisms. These results provide genetic and structural evidence that H. influenzae oafA is required for phase variable O-acetylation of LPS and functional evidence to support the role of O-acetylation of LPS in pathogenesis.  相似文献   
185.
In this research, it has been aimed to evaluate the improvement effects of alpha lipoic acid (ALA), ascorbic acid-6-palmitate (AA6P), fish oil (FO), and their combination (COM) on some biochemical properties in erythrocytes of streptozotocin (STZ)-induced diabetic male rats. According to experimental results, glutathione (GSH) level in erythrocytes decreased in diabetes (P < 0.01), D + ALA, and D + AA6P groups (P < 0.001). Malonaldehyde (MA) level increased in diabetes (P < 0.05), D + FO, and D + COM groups (P < 0.001), but its level in D + AA6P and D + ALA groups was lower in diabetes group (P < 0.01). Total lipid level in diabetes and diabetes plus antioxidant administered groups were higher than control. Total cholesterol level was high in diabetes and D + ALA groups (P < 0.05), but its level reduced in D + FO compared to control and diabetes groups, P < 0.05, < 0.001, respectively. Total triglyceride (TTG) level was high in the D + ALA (P < 0.05) and D + COM (P < 0.001) groups. In contrast, TTG level in blood of diabetes group was higher than diabetes plus antioxidant and FO administered groups (P < 0.001). According to gas chromatography analysis results, while the palmitic acid raised in diabetes group (P < 0.05), stearic acid in D + FO, D + ALA, and diabetes groups was lower than control (P < 0.05), oleic acid reduced in D + COM and D + FO groups, but its level raised in D + AA6P and D + ALA groups (P < 0.01). As the linoleic acid (LA) elevated in ALA + D, D + AA6P, and diabetes groups, linolenic acid level in diabetes, D + AA6P, and D + FO groups was lower than control (P < 0.001). Arachidonic acid (AA) decreased in D + ALA, D+ AA6P, and diabetes groups (P < 0.01), but its level in D + COM and D + FO was higher than control (P < 0.05). Docosahexaenoic acid (DHA) increased in D + AA6P and D + COM (P < 0.05). While the total saturated fatty acid level raised in diabetes group, its level reduced in D + ALA and D + FO groups (P < 0.05). In contrast, total unsaturated fatty acid level in D + ALA and D + FO groups was higher than control (P < 0.05). In conclusion, present data have confirmed that the combination of the ALA, AA6P, and FO have improvement effects on the recycling of GSSG to reduced GSH in erythrocytes of diabetic rats, and in addition to this, oxidative stress was suppressed by ALA and AA6P, and unsaturated fatty acid degree was raised by the effects of ALA and FO.  相似文献   
186.
West Nile virus (WNV), a mosquito-borne flavivirus with significant impact on human and animal health, has recently demonstrated an expanded zone of activity globally. The aim of this study is to investigate the frequency and distribution of WNV infections in potential vectors and several mammal and avian species in Turkey, where previous data indicate viral circulation. The study was conducted in 15 provinces across Turkey during 2011–2013. In addition, the entomological study was extended to 4 districts of the Turkish Republic of Northern Cyprus. WNV exposure was determined in humans, horses, sheep and ducks from Mersin, Sanliurfa, Van and Kars provinces of Turkey, via the detection of neutralizing antibodies. WNV RNA was sought in human and equine samples from Mersin, Adana and Mugla provinces. Field-collected mosquitoes from 92 sites at 46 locations were characterized morphologically and evaluated for viral RNA. Neutralizing antibodies were identified in 10.5% of the 1180 samples studied and detected in all species evaluated. Viral nucleic acids were observed in 5.9% of 522 samples but only in horses. A total of 2642 mosquito specimens belonging to 15 species were captured, where Ochlerotatus caspius (52.4%), Culex pipiens sensu lato (24.2%) comprise the most frequent species. WNV RNA was detected in 4 mosquito pools (1.9%), that comprise Oc. caspius Cx. pipiens s.l. and DNA barcoding revealed the presence of Cx. quinquefasciatus and Cx. perexiguus mosquitoes in infected Culex pools. All WNV partial sequences were characterized as lineage 1 clade 1a. These findings indicate a widespread WNV activity in Turkey, in Eastern Thrace and Mediterranean-Aegean regions as well as Southeastern and Northeastern Anatolia.  相似文献   
187.
188.
Maras Powder (MP) is a special kind of smokeless tobacco widely used in the southeast region of Turkey especially in Kahramanmaras and Gaziantep and other southeastern cities. It is obtained from a tobacco species, Nicotiana rustica L and ash of oak or grapevine wood. Tobacco may increase oxidative stress, which is related to the products of the oxygen metabolism taking place in all cells. Cellular antioxidants, e.g. catalase (CAT), superoxide dismutase (SOD) and glucose 6-phosphate dehydrogenase (G6PD) protect the cell against oxidative damage. An imbalance between the ROS and antioxidants in favour of ROS is described as oxidative stress. In this study, we aimed to investigate the effect of MP on antioxidant enzyme levels and lipid peroxidation. We measured malondialdehyde (MDA), CAT, SOD and G6PD levels in blood of 68 MP users and 30 healthy controls who did not use MP. CAT, SOD and G6PD levels were lower in MP users than in the controls. On the other hand, lipid peroxidation levels (MDA), one of the best indicators of cytological damage, was increased in MP users compared with the controls. The present study showed that MP increases oxidative stress, which may cause many systemic disorders, including arteriosclerosis.  相似文献   
189.
The pomegranate has been used traditionally in Coruh Valley in Turkey for a long time; fruits are harvested from wild, semi-domesticated and cultivated trees. In the valley, it occurs in general along with olive trees. We sampled 23 wild-grown pomegranate genotypes sampled from different parts of Coruh Valley and compared them using RAPD primers to determine genetic variability. Eighty-six RAPD primers were used for molecular characterizations, among which 12 gave reliable polymorphic patterns. These primers generated 145 RAPD bands of which 91% were polymorphic. The highest polymorphism ratio was observed with primers OPY06, OPY13, OPBA03, OPBB03, OPBB07, and OPBB09 (100%), while the lowest was with OPBB09 and OPBB10 (75%). The band size was between 250 and 2400 bp. There were five main clusters in the dendrogram; the highest genetic similarity was 0.24 and the lowest was 0.08.  相似文献   
190.
Common structural motifs of Haemophilus influenzae lipopolysaccharide (LPS) are globotetraose [beta-d-GalpNAc-(1-->3)-alpha-d-Galp-(1-->4)-beta-d-Galp-(1-->4)-beta-d-Glcp] and its truncated versions globoside [alpha-d-Galp-(1-->4)-beta-d-Galp-(1-->4)-beta-d-Glcp] and lactose [beta-d-Galp-(1-->4)-beta-d-Glcp] linked to the terminal heptose (HepIII) of the triheptosyl inner-core moiety l-alpha-d-Hepp-(1-->2)-[PEA-->6]-l-alpha-d-Hepp-(1-->3)-l-alpha-d-Hepp-(1-->5)-[PPEA-->4]-alpha-Kdo-(2-->6)-lipid A. We report here structural studies of LPS from nontypeable H. influenzae strain 1124 expressing these motifs linked to both the proximal heptose (HepI) and HepIII at the same time. This novel finding was obtained by structural studies of LPS using NMR techniques and electrospray ionization mass spectrometry (ESI-MS) on O-deacylated LPS and core oligosaccharide material (OS) as well as ESI-MS(n)() on permethylated dephosphorylated OS. The use of defined mutants allowed us to confirm structures unambiguously and understand better the biosynthesis of each of the globotetraose units. We found that lgtC is involved in the expression of alpha-d-Galp-(1-->4)-beta-d-Galp in both extensions, whereas lic2A directs only the expression of beta-d-Galp-(1-->4)-beta-d-Glcp when linked to HepIII. The LPS of NTHi strain 1124 contained sialylated glycoforms that were identified by CE-ESI-MS/MS. A common sialylated structure in H. influenzae LPS is sialyllactose linked to HepIII. This structure exists in strain 1124. However, results for the lpsA mutant indicate that sialyllactose extends from HepI as well, a molecular environment for sialyllactose in H. influenzae that has not been reported previously. In addition, the LPS was found to carry phosphorylcholine, O-linked glycine, and a third PEA group which was linked to O3 of HepIII.  相似文献   
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