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51.
52.
Sukjoong Oh Dong Hoe Koo Min-Jung Kwon Kihyun Kim Cheolwon Suh Chang-Ki Min Sung-Soo Yoon Ho-Jin Shin Deog-Yeon Jo Jae-Yong Kwak Jin Seok Kim Sang Kyun Sohn Young-Don Joo Hyeon-Seok Eom Sung-Hyun Kim Yang Soo Kim ChulSoo Kim Yeung-Chul Mun Hawk Kim Dong Soon Lee Jae Hoon Lee 《Annals of hematology》2014,93(8):1353-1361
This study was designed to evaluate the prevalence of chromosomal abnormalities and to identify the specific abnormalities associated with poor prognosis. A total of 2,474 patients whose conventional cytogenetics were available at the time of diagnosis were evaluated via a nationwide registry. Normal metaphase cytogenetics was observed in 2,012 patients (81.3%). Among the 462 patients with chromosomal abnormalities, there were 161 (34.8%) patients with hyperdiploidy, 197 (42.6%) with pseudodiploidy, 79 (17.1%) with hypodiploidy, and 25 (5.5%) with near-tetraploidy. Deletion 13 (Δ13) in metaphase was observed in 167 patients (6.8%). Fluorescent in situ hybridization (FISH) was carried out in 967 patients (39.1%), and 66 (13.7%) out of 482 and 63 (10.3%) out of 611 patients were positive for t(4;14) and del(17p), respectively. With a median follow-up duration of 25.1 months, the median overall survival (OS) was 51.2 months (95% confidence interval, 46.5–55.9 months). In univariate analysis, the following four chromosomal abnormalities were significantly associated with a poor survival outcome: Δ13, hypodiploidy, del(13q) in FISH, and del(17p) in FISH. In the subsequent multivariate analysis, in which del(13q) and del(17p) in FISH were excluded due to a relatively low number of patients, Δ13 and hypodiploid status were independently associated with a poor survival outcome after adjusting for important clinical factors, including age, sex, performance, beta2-microglobulin, albumin, and lactate dehydrogenase (LDH). Using conventional metaphase cytogenetics, we confirmed that both Δ13 and hypodiploid status were robust poor prognostic factors. The metaphase karyotyping should remain the primary cytogenetic tool and an essential investigation for risk stratification in newly diagnosed multiple myeloma patients. 相似文献
53.
Nirpesh Adhikari Sanjiv Neupane Yam Prasad Aryal Mi Choi Wern‐Joo Sohn Youngkyun Lee Jae‐Kwang Jung Jung‐Hong Ha So‐Young Choi Jo‐Young Suh Ji‐Youn Kim Mun‐Chual Rho Tae‐Hoon Lee Hitoshi Yamamoto Chang‐Hyeon An Sang‐Hyun Kim Seo‐Young An Jae‐Young Kim 《Journal of periodontal research》2019,54(5):533-545
54.
Jee Hyun Ham Han Yi Mun Kyung Sunwoo Jin Yong Hong Young H. Sohn Phil Hyu Lee 《Journal of neurology》2014,261(8):1628-1635
Cerebral microbleeds (CMBs) are known to be associated with cognitive impairments in the elderly and in patients with various diseases; however, the nature of this association has not yet been evaluated in Parkinson’s disease (PD). In the present study, we analyzed the incidence of CMBs in PD according to cognitive status, and the impact of CMBs on cognitive performance was also evaluated. The CMBs in PD with dementia (n = 36), mild cognitive impairment (MCI, n = 46), or cognitively normal (n = 41) were analyzed using conventional T2*-weighted gradient-recalled echo images. Additionally, the relationship between the presence of CMBs and cognitive performance on individual tests of cognitive subdomains was analyzed using a detailed neuropsychological test. CMBs occurred more frequently in PD patients with dementia (36.1 %) compared to those with MCI (15.2 %), those who are cognitively normal (14.6 %), and normal controls (12.2 %, p = 0.025). However, the significant association of CMBs with PD dementia disappeared after adjusting white matter hyperintensities (WMHs) as a covariate. The frequencies of deep, lobar, and infratentorial CMBs did not differ among the four groups. After adjusting for age, sex, years of education, and WMHs, PD patients with CMBs had poorer performance in attention domain compared with those without CMBs (34.9 vs 42.6, p = 0.018). The present data demonstrate that even though CMBs were inseparably associated with the presence of WMHs, CMBs occur more commonly in PD patients with dementia than in those without dementia. Additionally, the burden of CMBs may contribute to further cognitive impairment in PD. 相似文献
55.
56.
Chandipura virus (CHPV) is an emerging tropical pathogen in India. The virus has been reported to be associated with an acute encephalitis syndrome in young children with a case fatality rate of 55% to 75%. Clinical management with symptomatic treatment is the only option available to treat infected patients. No vaccines are available for prophylaxis. In light of the prophylactic limitations, antiviral therapy would play an important role in control of CHPV infection. In the present study, ribavirin (RBV), an antiviral drug widely accepted for human use and having an antiviral effect on many RNA and DNA viruses, was tested against the CHPV. A screening assay that scores for the virus-mediated plaque formation in the cultured Vero cells was used. RBV exhibited 50% inhibitory concentration (IC50) at 89.84 ± 1.8 µM. The drug was very effective when the cells were treated either within an hour postinfection or 4 to 6 hours before infection. The plaque morphology was different in RBV treated cells; the plaques were smaller in size as compared with the plaques in the virus infected cells. The study reports the antiviral activity of RBV against CHPV, and hence, suggests the possible utility of RBV in CHPV infected patients to mitigate the disease. A further clinical trial is needed before introducing the drug for human use against CHPV infection. 相似文献
57.
Norwahyu Jusoh Yin Fong Yeong Serene Sow Mun Lock Li Sze Lai Malik Shoaib Suleman 《RSC advances》2020,10(6):3493
Generation of biogas from organic substances is an attractive evolution of energy generation from fossil-based energy supply to renewable resources. In order to exhibit viability in terms of technical execution while being economically feasible, successful purification strategies for biomethane formation must be applicable to industrial gas streams at realistic pressures and temperatures. Membrane-based upgrading technologies have great potential to promote biogas processes because they involve less energy and low maintenance. However, the development of membranes with good polymer-filler contact and minimum defects remains a great challenge. Hitherto, researchers have been making many attempts at developing an established route to fabricate thin-film composite membranes. In the present work, an innovative coupling between Linde T and fluorinated polyimide was employed for biogas upgrading. A facile technique for membrane fabrication was proposed via optimization of the fabrication parameters. The results indicated that composite membrane fabricated with 2 hours of total dispersion duration demonstrated a homogeneous distribution of Linde T particles in the fluorinated polyimide matrix and improved the separation characteristics by up to 172% in upgrading biomethane quality. Thus, the fabricated membrane is feasible to be employed for large-scale and lucrative production with enhanced performance in biogas purification via the feasible fabrication method employed in this work.Generation of biogas from organic substances is an attractive evolution of energy generation from fossil-based energy supply to renewable resources. 相似文献
58.
Yeong-Heum Yeon Ha-Eun Shim Jin-Hyung Park Nam-Ho Lee Jae-Yeon Park Moon-Sik Chae Jung-Ho Mun Jae-Hyun Lee Hui-Jeong Gwon 《Materials》2022,15(1)
The scission rates of polystyrene and fluorinated polystyrene irradiated in an irradiation facility with Co-60 γ-rays were determined using molecular dynamics simulation and gel permeation chromatography (GPC) molecular weight distributions. The prediction was based on the assumption that γ-ray energy is transferred to the initial velocity of the primary knock-on atom. We employed a molecular dynamics simulation procedure to compute the changes in bond length between the connections for selected values of the absorbed dose and compared the calculated values with measurements made on the irradiated samples. The samples were exposed to four different absorbed doses of 25, 50, 75, and 100 kGy. The scission process and scission ratio were simulated with LAMMPS with ReaxFF potential for each bond, and we compared the simulation results with the experimental data especially measuring average molecular weight to evaluate the effect of fluorination on radiation enhancement. 相似文献
59.
60.
Surgical excision is the treatment of choice for lipomas. However, linear incision methods or minimal extraction techniques often do not provide a sufficient surgical view. Therefore, removing large lipomas is often difficult. To present the Z‐incision and half Z‐incision designs for lipoma extraction, this retrospective study analyzed lipomas surgically excised at our institution between September 2015 and December 2018. The area of surgical field exposed by the Z‐incision versus that exposed by the linear incision was calculated using a schematic model. Cure rate, complications, and surgical field area were investigated. A total of 84 lipomas were included. A Z‐ or half Z‐incision was used to treat 30 lipomas, while a linear incision was used to treat 54 lipomas. The mean diameter of the mass in the Z‐ or half Z‐incision group was 47.7 mm (range, 15–160 mm), larger than that in the linear incision group (25.5 mm; range, 7–59 mm) (p < .001). The Z‐incision involved making rectangular windows by lifting 2 triangular flaps. According to our mathematical model, the Z‐incision provided a larger surgical field area than that provided by the linear incision based on stretched angles (1.81 times larger at 30° and 3.14 times larger at 15°). The Z‐ and half Z‐incisions were successfully performed in all but 1 lipoma (29 lipomas, 96.7%). There was 1 lipoma that resulted in postoperative complications (seroma, 3.3%). The Z‐incision design can be a useful alternative technique for the extirpation of lipomas, especially large lipomas. Here, we proposed a surgical algorithm for lipoma surgery based on tumor size. 相似文献