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81.
Detection of YMDD motif mutants by oligonucleotide chips in lamivudine-untreated patients with chronic hepatitis B virus infection 总被引:9,自引:0,他引:9
Heo J Cho M Kim HH Shin YM Jang HJ Park HK Kim CM Kim GH Kang DH Song GA Yang US 《Journal of Korean medical science》2004,19(4):541-546
Lamivudine, a nucleoside analogue, has been used widely as an effective antiviral agent for the treatment of patients with chronic hepatitis B virus (HBV) infection. However, the YMDD motif mutation of HBV polymerase resistant to lamivudine occurs very frequently after long term therapy. We developed an oligonucleotide chip for the detection of YMDD motif mutants resistant to lamivudine and investigated the prevalence of the mutants in patients with chronic HBV infection who had not been treated by lamivudine before. Forty patients who had not been treated with lamivudine were included in this study. Serum samples were tested by the oligonucleotide chips designed for detection of wild-type YMDD motif, M552V and M552I. Samples were confirmed by restriction fragment length polymorphism (RFLP) and direct sequencing. M552I mutants were detected by the oligonucleotide chips in 7.5% (3/40) of chronic HBV infected patients (2 chronic hepatitis and 1 cirrhosis). The results were in accordance with those of RFLP. YMDD motif mutants occur as natural genome variabilities in patients with chronic HBV infection who had not been treated with lamivudine before. Oligonucleotide chip technology is a reliable and useful diagnostic tool for the detection of mutants resistant to antiviral therapy in chronic HBV infection. 相似文献
82.
The effects of different molecular weights of hyaluronic acid (HA), a major component of extracellular matrix, on gap junctional intercellular communication (GJIC) in normal human dermal fibroblasts (NHDF cells) were investigated. NHDF cells were cultured for 4 days with different molecular weights of HA and then the extent of GJIC was assessed by the scrape-loading dye transfer method, using Lucifer yellow. The area of dye transfer was greater in the dishes coated with HA than in those to which HA was added. Thus, NHDF cells cultured on surfaces coated with high molecular weight (HMW) HA (MW, 800 kDa) showed greatly enhanced GJIC. Furthermore, another aim of this study was to evaluate the effects of different molecular weights of HA on the production of FGF-2 and KGF, because both are important cytokines produced by NHDF cells. When FGF-2 and KGF cultured levels of cell extracts and media were determined by ELISA, both levels were significantly enhanced when cells were grown on plates coated with HMW HA. This finding indicated that the function of gap junction channels in NHDF cells grown on plates coated with HMW HA may promote the biosynthesis of growth factors such as FGF-2 and KGF. 相似文献
83.
Enkhtuvshin Gereltzul Yoshiyuki Baba Naoto Suda Momotoshi Shiga Maristela Sayuri Inoue Michiko Tsuji Insik Shin Yukio Hirata Kimie Ohyama Keiji Moriyama 《Journal of human genetics》2008,53(10):941-946
This is a report of a 27-year-old woman with an unusual de novo chromosomal abnormality. Mosaicism was identified in peripheral
blood cells examined by standard G-bands by trypsin using Giemsa (GTG) analysis and fluorescence in situ hybridization (FISH)
analysis with chromosome-18 region-specific probes, 46,XX,del(18)(pter → q21.33:)[41], 46,XX,r(18)(::p11.21 → q21.33::)[8],
and 46,XX,der(18)(pter → q21.33::p11.21 → pter)[1]. On the other hand, the karyotype of periodontal ligament fibroblasts was
nonmosaic, 46,XX, der(18)(pter → q21.33::p11.21 → pter)[50]. All cell lines appeared to be missing a portion of 18q (q21.33 → qter).
The pattern of the dup(18p)/del(18q) in the rod configuration raises the possibility of an inversion in chromosome 18 in one
of the parents. However, no chromosomal anomaly was detected in either parent. The most probable explanation is that de novo
rod and ring configurations arose simultaneously from an intrachromosomal exchange. The unique phenotype of this patient,
which included primary hypothyroidism and primary hypogonadism, is discussed in relation to her karyotype. 相似文献
84.
In-Suk Kim Eun Sil Park Jae Young Lim Chang-Seok Ki Hyun Sook Chi 《Journal of Korean medical science》2008,23(6):1105-1108
Although acquired mutations in the GATA1 gene have been reported for Down syndrome-related acute megakaryoblastic leukemia (DS-AMKL) in Caucasians, this is the first report of a Korean Down syndrome patient with AMKL carrying a novel mutation of the GATA1 gene. A 3-yr-old Korean girl with Down syndrome was admitted to our hospital complaining of pallor and fever. The findings of a peripheral blood smear and bone marrow study were compatible with the presence of AMKL. A chromosome study showed 48,XX,-7,+21c,+21,+r[3]/47,XX,+21c[17]. Following GATA1 gene mutation analysis, a novel mutation, c.145dupG (p.Ala49GlyfsX18), was identified in the N-terminal activation domain of the GATA1 gene. This mutation caused a premature termination at codon 67 and expression of an abnormal GATA-1 protein with a defective N-terminal activation domain, and the absence of full-length GATA-1 protein. This case demonstrates that a leukemogenic mechanism for DS-AMKL is contributed by a unique collaboration between overexpressed genes from trisomy 21 and an acquired GATA1 mutation previously seen in Caucasians and now in a Korean patient. 相似文献
85.
Youn Kyung Kee Sang Youb Han Duk-Hee Kang Jung Woo Noh Kyung Hwan Jeong Gheun-Ho Kim Yang Wook Kim Beom Seok Kim 《Yonsei medical journal》2021,62(1):41
PurposeOral adsorbents delay disease progression and improve uremic symptoms in patients with chronic kidney disease (CKD). DW-7202 is a newly developed oral adsorbent with high adsorptive selectivity for uremic toxins. We evaluated patient preference for and adherence to DW-7202 versus AST-120 therapy and compared treatment efficacy and safety in patients with pre-dialysis CKD.Materials and MethodsA seven-center, randomized, open-label, two-way crossover, active-controlled, phase IV clinical trial was conducted. Patients with stable CKD were randomly assigned to receive DW-7202 (capsule type) or AST-120 (granule type) for 12 weeks. The groups then switched to the other adsorbent and took it for the next 12 weeks. Patient preference was the primary outcome. Secondary outcomes included changes in estimated glomerular filtration rate (eGFR) and serum creatinine, cystatin C, and indoxyl sulfate (IS) levels.ResultsSignificantly more patients preferred DW-7202 than AST-120 (p<0.001). Patient adherence improved after switching from AST-120 to DW-7202; there was no apparent change in adherence after switching from DW-7202 to AST-120. Changes in eGFR and serum creatinine, cystatin C, and IS levels were not significantly different according to adsorbent type. There was also no significant difference in the incidences of adverse events during treatment with DW-7202 and AST-120.ConclusionDW-7202 can be considered as an alternative to AST-120 in patients who cannot tolerate or show poor adherence to granule type adsorbents. Further studies to evaluate factors affecting patient preferences and improved adherence are warranted (Clinical trial registration No. ). NCT02681952相似文献
86.
Lithium chloride (LiCl) at doses sufficient to induce conditioned taste aversion (CTA) causes c-Fos expression in the relevant brain regions and activates the hypothalamic-pituitary-adrenal (HPA) axis. It has been suggested that nitric oxide (NO) in the central nervous system may play a role not only in the activation of HPA axis but also in CTA learning, and that LiCl may activate the brain NO system. To determine the role of NO in lithium-induced CTA, we examined the lithium-induced CTA, brain c-Fos expression, and plasma corticosterone level with Nomega-nitro-L-arginine methyl ester (L-NAME) pretreatment. Intraperitoneal L-NAME (30 mg/kg) given 30 min prior to LiCl significantly decreased lithium-induced c-Fos expression in the brain regions implicated in CTA learning, such as the hypothalamic paraventricular nucleus (PVN), central nucleus of amygdala (CeA), and nucleus tractus of solitarius. However, either the lithium-induced CTA acquisition or the increase in plasma corticosterone was not attenuated by l-NAME pretreatment. These results suggest that NO may be involved in lithium-induced neuronal activation of the brain regions, but not in the CTA acquisition or the HPA axis activation. 相似文献
87.
The purpose of this study was to investigate the epidemiologic characteristics of the death by poisoning in Korea. We recoded the Death Certificates Database by injury based on the short version of the International Classification of External Causes of Injuries (ICECI). We evaluated the mortality rate by total injury and poisoning, and analyzed the mortality rate by age, gender, year and month, toxic agent, and intent. Adjusted odds ratios were calculated to evaluate the effects of socioeconomic factors on suicidal poisoning death. The total number of death cases by injury was 346,656. The proportion of death cases by injury decreased from 13.53% of all death cases in 1991 to 11.89% in 2001. However, the mortality rate by poisoning increased rapidly from 1998, and then remained stable. The number of suicidal poisoning deaths has gradually increased, and its mortality rate was 6.41 (per 100,000) in 2001. Major toxic agents were pesticides and herbicides (50.90%) in 2001. Adjusted odds ratios of suicidal poisoning versus other poisonings showed significant differences in education attainment, region, and marital status. In conclusion, the mortality rate by poisoning has increased, and the proportion of suicidal poisoning also has increased compared to that of accidental poisoning. 相似文献
88.
Yoshinori Seko Shigeru Ishiyama Toshiro Nishikawa Takeshi Kasajima Michiaki Hiroe Shin Suzuki Sugao Ishiwata Sachio Kawai Yuetsu Tanaka Miyuki Azuma Tetsuji Kobata Hideo Yagita Ko Okumura Ryozo Nagai 《Cardiovascular pathology》2002,11(3):166-170
BACKGROUND: T-cell-mediated myocardial damage is known to be involved in acute myocarditis and dilated cardiomyopathy. Recently, we found that tumor necrosis factor (TNF) ligand superfamily costimulatory molecules, especially 4-1BBL, played an important role in the myocardial damage of murine acute viral myocarditis. METHODS AND RESULTS: To investigate the roles for CD27L, CD30L, OX40L and 4-1BBL, which belong to TNF ligand superfamily, in the development of acute myocarditis and dilated cardiomyopathy, we analyzed the expression of these antigens in the myocardial tissues of patients with acute myocarditis and dilated cardiomyopathy. We also examined expression of the receptors for these molecules, CD27, CD30, OX40 and 4-1BB, which belong to TNF receptor superfamily, on the infiltrating cells. Strong expression of CD27L, CD30L and 4-1BBL and weak to moderate expression of OX40L was found in the cardiac myocytes of patients with acute myocarditis. Moderate expression of CD27L, CD30L and 4-1BBL and weak expression of OX40L was found on the cardiac myocytes of patients with dilated cardiomyopathy. Most of the infiltrating cells expressed CD27, CD30 and 4-1BB and a part of the infiltrating cells expressed OX40. CONCLUSIONS: Our findings suggest that expression of TNF ligand superfamily costimulatory molecules on cardiac myocytes may play a role in the cell-mediated myocardial damage in patients with acute myocarditis and dilated cardiomyopathy as in murine viral myocarditis. 相似文献
89.
Kouroku Y Fujita E Jimbo A Kikuchi T Yamagata T Momoi MY Kominami E Kuida K Sakamaki K Yonehara S Momoi T 《Human molecular genetics》2002,11(13):1505-1515
Accumulation of unfolded and malfolded proteins causes endoplasmic reticulum (ER) stress, stimulating unfolded protein response (UPR) and c-Jun N-terminal kinase (JNK) activation and activating caspase-12 located on the ER. Little is known about the relationship between the ER stress and polyglutamine [poly(Q)] aggregates. Poly(Q)72 repeats [poly(Q)(72)] induced the stimulation of ER stress signals such as JNK activation, upregulation of Grp78/Bip and caspase-12 activation in C2C5 cells. We prepared antiserum against the cleavage site of mouse caspase-12 at D(318) (anti-m12D318), and showed that poly(Q)(72) with perinuclear aggregates, cytoplasmic inclusions and nuclear inclusions stimulated JNK activation and anti-m12D318 immunoreactivity, but poly(Q)(72) with dispersed aggregates and small nuclear aggregates showed a significantly less effect. Poly(Q)(72) and poly(Q)(11) dispersed in cytoplasm did not. Anti-m12D318-positive cells showed apoptotic features. Unlike anti-m8D387 immunoreactivity, the anti-m12D318 immunoreactivity was not coaggregated with poly(Q). Ac-IETD-fmk (caspase-8 inhibitor) and Ac-DEVD-CHO (caspase-3 inhibitor) did not prevent the anti-m12D318 immunoreactivity induced by poly(Q)(72) aggregates. Anti-m12D318 immunoreactivity was detected in caspase-8(-/-) and caspase-3(-/-) mouse embryonic fibroblasts expressing poly(Q)(72) aggregates. Thus, caspase-12 was activated by poly(Q)(72) aggregates via a pathway independent of caspase-8 and caspase-3 activation, and caspase-12 activation was closely associated with poly(Q) aggregate-mediated cell death. Stimulation of ER stress signals may be involved in the pathogenesis of neurodegenerative disorders with poly(Q) expansion. 相似文献
90.
The effects of different types of clothing on human deep body temperature were studied with six healthy male subjects in a supine posture. Two clothing ensembles were employed for the present study: A covered the whole body area with garments except the face (1.97 clo) and B covered only the trunk and the upper half of the extremities with garments (1.53 clo). The experiment was carried out in a climatic chamber at 55% ± 5% relative humidity under cooling and warming temperatures: the temperature was changed from 22°C to 10°C (cooling) and returned to 22°C again (warming). The major findings were: rectal temperature (T
re) continued to decrease gradually in A throughout the experiment, whereas in B it increased during cooling, and returned to previous levels during warming. As a result, Tre and chest skin temperature were maintained at a higher level in B than in A. Internal tissue conductances were greater in A than in B both during cooling and during warming. Thermal comfort appeared to have been influenced more by the rate of skin temperature change than by the level of skin temperature per se. It was concluded that peripheral vasoconstriction in B induced less heat flow from core to shell, and, thus, the core temperature was maintained at a higher level in B than in A. 相似文献