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41.
Ihsan Ullah Eun-Kyung Jang Min-Sung Kim Jin-Ho Shin Gun-Seok Park Abdur Rahim Khan Sung-Jun Hong Byung-Kwon Jung JungBae Choi YeongJun Park Yunyoung Kwak Jae-Ho Shin 《Toxins》2014,6(7):2024-2040
Photorhabdus temperata is an entomopathogenic enterobacterium; it is a nematode symbiont that possesses pathogenicity islands involved in insect virulence. Herein, we constructed a P. temperata M1021 cosmid library in Escherichia coli XL1-Blue MRF` and obtained 7.14 × 105 clones. However, only 1020 physiologically active clones were screened for insect virulence factors by injection of each E. coli cosmid clone into Galleria mellonella and Tenebrio molitor larvae. A single cosmid clone, PtC1015, was consequently selected due to its characteristic virulent properties, e.g., loss of body turgor followed by death of larvae when the clone was injected into the hemocoel. The sequence alignment against the available sequences in Swiss-Prot and NCBI databases, confirmed the presence of the mcf gene homolog in the genome of P. temperata M1021 showing 85% homology and 98% query coverage with the P. luminescens counterpart. Furthermore, a 2932 amino acid long Mcf protein revealed limited similarity with three protein domains. The N-terminus of the Mcf encompassed consensus sequence for a BH3 domain, the central region revealed similarity to toxin B, and the C-terminus of Mcf revealed similarity to the bacterial export domain of ApxIVA, an RTX-like toxin. In short, the Mcf toxin is likely to play a role in the elimination of insect pests, making it a promising model for use in the agricultural field. 相似文献
42.
The use of wireless sensor networks (WSN) in healthcare applications is growing in a fast pace. Numerous applications such
as heart rate monitor, blood pressure monitor and endoscopic capsule are already in use. To address the growing use of sensor
technology in this area, a new field known as wireless body area networks (WBAN or simply BAN) has emerged. As most devices
and their applications are wireless in nature, security and privacy concerns are among major areas of concern. Due to direct
involvement of humans also increases the sensitivity. Whether the data gathered from patients or individuals are obtained
with the consent of the person or without it due to the need by the system, misuse or privacy concerns may restrict people
from taking advantage of the full benefits from the system. People may not see these devices safe for daily use. There may
also possibility of serious social unrest due to the fear that such devices may be used for monitoring and tracking individuals
by government agencies or other private organizations. In this paper we discuss these issues and analyze in detail the problems
and their possible measures. 相似文献
43.
Platelet activation leads to the incorporation of 32[PO4(2-)] into bovine coagulation factor Va and recombinant human factor VIII. In the presence of the soluble fraction from thrombin-activated platelets and (gamma-32P) adenosine triphosphate, radioactivity is incorporated exclusively into the M(r) = 94,000 heavy chain (H94) of factor Va and into the M(r) = 210,000 to 90,000 heavy chains as well into the M(r) = 80,000 light chain of factor VIII. Proteolysis of the purified phosphorylated M(r) = 94,000 factor Va heavy chain by activated protein C (APC) gave products of M(r) = 70,000, 24,000, and 20,000. Only the intermediate M(r) = 24,000 fragment contained radioactivity. Because the difference between the M(r) = 24,000 and M(r) = 20,000 fragments is located on the COOH-terminal end of the bovine heavy chain, phosphorylation of H94 must occur within the M(r) = 4,000 peptide derived from the carboxyl-terminal end of H94 (residues 663 through 713). Exposure of the radioactive factor VIII molecule to thrombin ultimately resulted in a nonradioactive light chain and an M(r) = 24,000 radioactive fragment that corresponds to the carboxyl-terminal segment of the A1 domain of factor VIII. Based on the known sequence of human factor VIII, phosphorylation of factor VIII by the platelet kinase probably occurs within the acidic regions 337 through 372 and 1649 through 1689 of the procofactor. These acidic regions are highly homologous to sequences known to be phosphorylated by casein kinase II. Results obtained using purified casein kinase II gave a maximum observed stoichiometry of 0.6 mol of 32[PO4(2-)]/mol of factor Va heavy chain and 0.35 mol of 32[PO4(2-)]/mol of factor VIII. Phosphoamino acid analysis of phosphorylated factor Va by casein kinase II or by the platelet kinase showed only the presence of phosphoserine while phosphoamino acid analysis of phosphorylated factor VIII by casein kinase II showed the presence of phosphothreonine as well as small amounts of phosphoserine. The platelet kinase responsible for the phosphorylation of the two cofactors was found to be inhibited by several synthetic protein kinase inhibitors. Finally, partially phosphorylated factor Va was found to be more sensitive to APC inactivation than its native counterpart. Our findings suggest that phosphorylation of factors Va and VIIIa by a platelet casein kinase II- like kinase may downregulate the activity of the two cofactors. 相似文献
44.
Although gastrointestinal diseases are reported at various times throughout the year, some particular seasons are associated with a higher incidence of these diseases. This study aimed to identify the seasonal variations of peptic ulcer (PU), peptic ulcer bleeding (PUB), and acute pancreatitis (AP) in South Korea.We conducted a retrospective, observational cohort study of all subjects aged >18 years between 2012 and 2016 using the Health Insurance Review and Assessment-National Patient Samples database, previously converted to the standardized Observational Medical Outcomes Partnership-Common Data Model. We assessed the overall seasonal variations of PU, PUB, and AP and further analyzed seasonal variations according to age and sex subgroups.In total, 14,626 patients with PU, 3575 with PUB, and 9023 with AP were analyzed for 5 years. A clear seasonal variation was noted in PU, with the highest incidence rate during winter, the second highest during spring, the third highest during summer, and the lowest incidence during autumn for 5 years (P < .001). PUB also showed significant seasonal fluctuations, with winter peak for 4 years, except 1 year, which had a spring peak (P < .001). However, AP showed no clear seasonal variations (P = .090). No significant differences in the seasonal variation of PU, PUB, and AP were observed according to sex and age subgroups (<60 years vs ≥60 years).Seasonal variation of PU and PUB should be considered when determining allocation of available health care resources. 相似文献
45.
46.
Prognostic significance of bcl-2, bax,and p53 expression in diffuse large B-cell lymphoma 总被引:6,自引:0,他引:6
Sohn SK Jung JT Kim DH Kim JG Kwak EK Park Ti Shin DG Sohn KR Lee KB 《American journal of hematology》2003,73(2):101-107
Diffuse large B-cell lymphoma (DLCL) exhibits heterogeneous clinical features and varies markedly in response to treatment and prognosis. Because apoptosis-related proteins may play an important role in predicting the prognosis of DLCL, the current study investigated the prognostic significance of a high level of bcl-2, bax, and p53 expression in relation to clinical characteristics in patients with DLCL. Paraffin-embedded specimens from 94 patients with de novo DLCL were analyzed immunohistochemically for bcl-2, bax, and p53 gene expression. Cases with a positive immunohistological stain in more than 50% of the tumor cells were considered to have DLCL-positive expression. Patients were treated optimally, i.e., with radiotherapy including brief cycles of CHOP or CHOP-like regimens for patients with stage 1-2A diseases and with at least 6 cycles of CHOP or CHOP-like regimens for stage 2B-4 diseases. The responses to therapy and survival were then analyzed in 94 uniformly staged patients. bcl-2 expression was identified in 24 patients (26.4%), bax expression in 35 patients (37.6 %), and p53 expression in 21 patients (22.6%). bax expression proved to be a statistically significant prognostic factor in predicting the overall survival (OS) (P = 0.0015) and disease-free survival (DFS) (P = 0.0052), regardless of other clinical factors or immunohistological results. There was no significant difference in the OS (P = 0.0682) or DFS (P = 0.088) between the bcl-2-positive (n = 24) and bcl-2-negative (n = 67) groups. However, bcl-2 expression was found to be unfavorably associated with the OS (P = 0.0054) in a confined group with low (n = 51) or low intermediate (n = 22) IPI scores. The expression of p53 exhibited no statistical correlation with the OS or DFS. A multivariate analysis revealed that IPI score, bulky mass, and bax expression were all significantly associated with the DFS or OS. bax and bcl-2 should be considered as independent biologic prognostic parameters in DLCL, thereby aiding in the identification of patient risk groups. As such, bcl-2-positive patients with a low or low intermediate IPI score, or without a high level of bax expression could be candidates for more intensive therapy or alternative therapeutic approaches. 相似文献
47.
Sun Kyung Moon Gye Sung Lee Earm Seok Lee Hyun Mo Kang Ji Hyun Lee Jae Su Kim Sung Cheol Kim Seung Soo Kwak 《Taehan Sohwagi Hakhoe chi》2007,50(5):340-343
Intestinal obstruction involves a partial or complete blockage of the bowel which results in the failure of intestinal contents to pass through. The mechanical causes of obstruction may include the followings: hernias, postoperative adhesions or scar tissue, impacted feces, gallstones, tumors, granulomatous processes, intussusception, volvulus, foreign bodies, and etc. Hernias are the third leading cause of intestinal obstruction by 10% approximately. However, most hernias are the cases with abdominal wall, inguinal or internal hernia. Femoral, obturator, lumbar, or sciatic hernia as the cause of obsturction is rare. Furthermore, the cases accompanying soft tissue necrosis are seldomly reported. Herein, we report a case of intestinal obstruction caused by strangulated femoral hernia accompanying soft tissue necrosis in a 78-years-old female patient. 相似文献
48.
PURPOSE: We investigated the role of race in predicting the likelihood of using hospice and dying in a hosptial among dual-eligible (Medicare and Medicaid) nursing home residents. DESIGN AND METHODS: This follow-back cohort study examined factors associated with hospice use and in-hospital death among non-Hispanic Black and non-Hispanic White dual-eligible nursing home residents (N = 30,765) who died in Florida during one of three years: 2000, 2001, or 2002. We used logistic regression models to identify independent predictors of hospice use and in-hospital death. RESULTS: After we controlled for other factors, Black residents were significantly less likely to use hospice and more likely to die in a hospital. Principal cause of death moderated the relationship between race and hospice use: Black residents were significantly less likely to use hospice than White residents among residents without cancer as principal cause of death, but there was no difference among residents with cancer as cause of death. Further analyses for each racial group revealed that the impact of cause of death in predicting hospice use was greater among Black residents than White residents. IMPLICATIONS: Hospice care offers many benefits, including reduced risk of in-hospital death, but Black nursing home residents are less likely to use hospice and may have different perceptions of need for hospice care compared with White residents. Future research and outreach efforts should focus on developing culturally sensitive, disease-focused end-of-life education and communication interventions that target residents, families, nursing home providers, and physicians. 相似文献
49.
Mannekomba R. Diagbouga Sandrine Morel Philippe Bijlenga Brenda R. Kwak 《European journal of clinical investigation》2018,48(9)
Background
Intracranial aneurysm (IA) is a disease of the vascular wall resulting in abnormal enlargement of the vessel lumen. It is a common pathology with a prevalence of 2%‐3% in the adult population. IAs are mostly small, quiescent and asymptomatic; yet, upon rupture, severe brain damage or even death is frequently encountered. In addition to clinical factors, hemodynamic forces, mainly wall shear stress (WSS), have been associated with the initiation of IAs and possibly with their risk of rupture. However, the mechanism by which WSS contributes to aneurysm growth and rupture is not completely understood.Design
PubMed and Ovid MEDLINE databases were searched. In addition, key review articles were screened for relevant original publications.Results
Current knowledge about the relation between WSS and IA has been obtained from both computational fluid dynamic studies in patients and experimental models of IA formation and growth. It is increasingly recognized that a high wall shear stress (gradient) participates to IA formation and that both low and high WSS can drive IA growth. Primary cilia (PC) play an important role as mechanosensors as patients with polycystic kidney disease, which is characterized by the absence or dysfunction of PC, have increased risk to develop IAs as well as increased risk of rupture.Conclusion
Wall shear stress is a key player in IA initiation and progression. It is involved in vascular wall remodelling and inflammation, processes underlying aneurysm pathophysiology. 相似文献50.
Ye Rim Nam Sae Bom Won Young-Shin Chung Chung Shil Kwak Young Hye Kwon 《Nutrition Research And Practice》2015,9(3):235-241