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121.
122.
Rapid detection of the hepatitis B virus YMDD mutant using TaqMan-minor groove binder probes 总被引:1,自引:0,他引:1
Hua R Tanaka Y Fukai K Tada M Seto M Asaoka Y Ohta M Goto T Kanai F Kato N Yoshida H Kawabe T Yokosuka O Omata M 《Clinica chimica acta; international journal of clinical chemistry》2008,395(1-2):151-154
BACKGROUND: TaqMan-minor groove binder (MGB) probes were used in a real-time PCR-based assay for the rapid and accurate detection of hepatitis B virus (HBV) YMDD mutants. METHODS: TaqMan-MGB probes were designed to distinguish between wild-type (YMDD) and mutant (YVDD and YIDD) strains of HBV. The detection limit and sensitivity of the assay were determined using a dilution series of a mixture of wild-type and mutant plasmids. Serum samples collected from four patients with chronic mutant HBV infections during lamivudine therapy were analyzed using this method. RESULTS: The detection limit for YVDD and YIDD was 10 and 50 copies, respectively, whereas the sensitivity was 10% within a mixed virus population. In the clinical samples, mutant strains of HBV could be detected at levels <2.6 log copies/ml of HBV DNA. While 15 of the 21 samples tested by this method were positive for the YMDD mutant, direct sequencing and a reverse hybridization line probe assay (INNO-LiPA HBV DR v2) detected the mutant strain in only 11 and 9 samples, respectively. Moreover, the data for 6 samples analyzed by TA cloning were fully consistent with our TaqMan PCR results. CONCLUSIONS: We successfully established a sensitive and accurate assay for the YMDD mutant of HBV. This method may be useful for monitoring patients treated with lamivudine. 相似文献
123.
Katoh M Yoshino M Asaoka K Aoki T Imamura H Kashiwazaki D Takano K Aida T 《Surgical neurology》2007,68(4):457-460
BACKGROUND: Cerebral amyloid angiopathy is a well-known disease that is predominantly recognized in elderly people and repeatedly causes large subcortical hemorrhages. These hemorrhages may be derived from vessel wall weakness because of Abeta depositions in the wall of the cortical and leptomeningeal arteries. Although vessel ruptures in CAA have been thought to occur in cortical arteries, it was recently demonstrated that the primary hemorrhage occurs in the subarachnoid space, particularly the cerebral sulci, as a result of multiple ruptures of meningeal arteries in some cases of subcortical hematoma caused by CAA. CASE DESCRIPTION: Case patient 1 was a 74-year-old woman who presented with epileptic seizure. A restricted SAH in the right frontal lobe was observed on MRI. Thirty-three days later, left hemiparesis occurred suddenly and a huge subcortical hematoma was observed in the right frontal lobe on CT. The hematoma was removed, and the patient was pathologically diagnosed with amyloid angiopathy. Case patient 2 was a 73-year-old man who presented with epileptic seizure. A restricted SAH in the right frontal lobe was observed on MRI. Twenty days later, left hemiparesis occurred suddenly and a huge subcortical hematoma was observed in the right frontoparietal area on CT. Hematoma removal was performed on both patients, and they were diagnosed pathologically with amyloid angiopathy. CONCLUSIONS: We report on the cases of 2 patients with CAA who presented with epileptic seizure and were found to have a restricted subarachnoid hematoma in the cerebral sulcus on MRI before their subcortical hemorrhages occurred. Both cases were diagnosed pathologically. This demonstrated that vessel ruptures in CAA can occur in the subarachnoid space, particularly the cerebral sulci, as a result of ruptures of meningeal arteries. A restricted SAH on CT/MRI could be a warning sign of a huge subcortical hemorrhage in CAA. 相似文献
124.
125.
Wong VW Wong GL Tsang SW Hui AY Chim AM Yiu KK Chan HY Chan FK Sung JJ Chan HL 《Antiviral therapy》2008,13(4):571-579
BACKGROUND: The long-term efficacy of lamivudine treatment for patients suffering from severe acute exacerbation of hepatitis B e antigen (HBeAg)-positive chronic hepatitis B is unknown. METHODS: Consecutive patients with severe acute exacerbation of HBeAg-positive chronic hepatitis B were prospectively recruited from 1999 to 2004 and treated with lamivudine. All patients had alanine aminotransferase (ALT) and serum bilirubin levels 10x and 3x above the upper limit of normal, respectively. HBeAg-positive patients without severe acute exacerbation served as controls. RESULTS: Forty-five patients with severe acute exacerbation and 31 controls were treated with lamivudine for a median of 2.8 (range 1.0-7.1) years and 3.8 (range 3.5-8.4) years, respectively. Compared with controls, patients with severe acute exacerbation had higher HBeAg seroconversion rates (78% versus 52%; P=0.02) and lower risk of virological breakthrough. However, 33% of patients with severe acute exacerbation still developed lamivudine resistance and virological breakthrough by year 5. HBV DNA levels at week 4 and prolonged baseline prothrombin time were independent factors associated with virological breakthrough. All patients with week 4 HBV DNA <3 log10 copies/ml had maintained virological response. Among 15 patients who stopped lamivudine after sustained HBeAg seroconversion for > or =6 months, 11 (73%) had virological relapse at a median of 1.4 (0.2-3.9) years. ALT increased beyond 10x the upper limit of normal in six (38%) patients who stopped lamivudine and two (7%) patients on maintained lamivudine treatment (P=0.02). CONCLUSION: Among patients with severe acute exacerbation of HBeAg-positive chronic hepatitis B treated with lamivudine, virological breakthrough and post-treatment relapse are common despite a high rate of HBeAg seroconversion. Severe hepatitis flare is also common particularly among patients developing virological relapse after discontinuation of lamivudine. 相似文献
126.
Bulsara KR Asaoka K Aliabadi H Kanaly C Friedman A Fukushima T 《Neurosurgical review》2008,31(3):299-302
Optimal surgical exposure during the transcondylar approach may result in injury to the hypoglossal nerve. This study evaluated the utility of three-dimensional computed tomography (3-D CT) as a means of obtaining detailed anatomic information in an individual patient prior to surgery involving the hypoglossal canal. We studied 20 hypoglossal canals in ten patients using 3-D CT reconstructed from 1-mm CT slices. Detailed anatomic measurements were performed to define the relationship of the hypoglossal canal to the occipital condyles and clivus. The relationship of the hypoglossal canal to the occipital condyles and clivus were extremely variable. From the outer table of the clivus in the midline, the extracranial opening of the hypoglossal canal was 20.3 + 2.7 mm (range 15.7-24.7 mm). The intracranial opening was 7.4 + 2.3 mm (range 6.2-11.5 mm) from the inner table of the clivus. From the superior aspect of the condyle, the inner opening was 11.0 + 1.4 mm (range 8.7-12.7 mm) and the outer opening was 19.1 + 2.4 mm (range 14.3-22.8 mm). From the lowest point of the condyle, the outer opening was 12.4 + 2.1 mm (range 9.1-15.6 mm). The posterior condylar emissary vein was 12.2 + 3.0 mm from the intracranial opening of the hypoglossal canal. Three-dimensional CT is a useful tool for assessing critical anatomic relationships and tailoring surgical approaches for individual patients. The amount of bone that can be safely removed without violating the hypoglossal canal can be determined preoperatively for each patient. 相似文献
127.
T Soeki N Fukuda H Shinohara N Takeichi H Tanaka K Bando Y Yui Y Tamura 《Journal of cardiology》1999,33(6):339-345
A 47-year-old man with hypertensive heart disease and left heart failure due to left ventricular diastolic dysfunction was admitted to our hospital because of emergent hypertension. Chest radiography on admission showed slight cardiomegaly and mild pulmonary congestion with right pleural effusion Echocardiography showed concentric hypertrophy and normal contraction of the left ventricular wall Pulsed Doppler left ventricular inflow velocity wave and pulmonary venous flow velocity wave disclosed restrictive filling patterns. After Ca antagonist, nitrate, and diuretics were administered, blood pressure was normalized, and left ventricular inflow velocity wave showed the relaxation abnormality pattern and pulmonary venous flow velocity wave showed the normal pattern. Radioiodinated iodine-123 metaiodobenzyl guanidine (123I-MIBG) imaging in the state of normalized blood pressure showed decreased heart to mediastinum ratio and increased washout rate. Left heart catheterization and angiography revealed normal end-diastolic pressure and coronary arteries, but coronary flow reserve evaluated with Doppler flow wire and intracoronary adenosine triphosphate administration was impaired: Plasma level of atrial and brain natriuretic peptides, which were markedly elevated on admission, decreased with the improvement of heart failure. Doppler flow velocity patterns, plasma levels of atrial natriuretic peptide and brain natriuretic peptide, cardiac sympathetic nerve activity, and coronary flow reserve might be useful for evaluating the severity of left ventricular diastolic dysfunction in patients with hypertensive heart disease. 相似文献
128.
Ryutaro Kira Yoshito Ishizaki Hiroyuki Torisu Masafumi Sanefuji Megumi Takemoto Kanji Sakamoto Shigetaka Matsumoto Yui Yamaguchi Naoko Yukaya Yasunari Sakai Kenjiro Gondo Toshiro Hara 《Brain & development》2010
Objective: A genetic predisposition to febrile seizures (FS) has long been recognized. The inheritance appears to be polygenic in small families or sporadic cases of FS encountered in daily clinical practice. To determine whether candidate genes are responsible for the susceptibility to FS, we have performed genetic association studies in FS patients and controls. Methods: The single-nucleotide polymorphisms (SNPs) of genes involved in immune response (interleukin (IL) 1B), endocannabinoid signaling (CNR1), acid–base balance (SLC4A3, SLC9A1, SLC9A3), gap junction channel (CX43), and GABAA receptor trafficking (PRIP1) were examined in 249 FS patients (186 simple and 63 complex FS) and 225 controls. Results: There were no significant differences in the allele frequencies of the SNPs between controls and all FS, simple FS, and complex FS patients. When the simple FS patients were divided into two groups according to either having (familial) or not having a family history of FS in close relatives (sporadic), there was a significant association between IL1B −511 SNP and sporadic simple FS (p = 0.003). Conclusions: These data suggest that cytokine genes may act as enhancers or attenuators of FS susceptibility. Genetic association study may be an effective approach to understanding the molecular basis of FS at least in a subgroup of patients. 相似文献
129.
Tadaki Nakahara Takashi Togawa Matsuo Nagata Kazunori Kikuchi Kazuo Hatano Nobuharu Yui Atsushi Kubo 《Annals of nuclear medicine》2002,17(7):583-591
The aims of this study were to compare the results of thallium-201 (Tl-201) SPECT, barium swallow and CT in the assessment
of the effect of preoperative chemoradiotherapy. This study consisted of 28 patients with advanced esophageal squamous cell
carcinoma (AESCC) who underwent the three imaging modalities before and after preoperative chemoradiotherapy. The results
were quantified using the bidimensional method for barium swallow and contrast-enhanced CT and the tumor-to-lung ratio for
SPECT. The percent decrease in these quantitative values after therapy was defined as %Dba, %Dct and %Dtl respectively. The
histological effect of the chemoradiotherapy was determined from the resected surgical specimen of the esophagus: grade 0,
100% viable tumor cells; grade la, 99–67%; grade 1 b, 66–34%; grade 2, 33–1%; grade 3, no viable cells. A statistically significant
difference of %Dtl between the subgroups of each grade was evident (p=0.0433), whereas no significant differences were evident
for %Dba (p=0.1778) or %Dct (p=0.7377). However, the overlap of %Dtl between these groups was marked. Although thallium-201
SPECT cannot be used to evaluate the therapeutic effect with acceptable accuracy, SPECT may be of additional value to barium
swallow and CT in assessing the response of AESCC to preoperative chemoradiotherapy. 相似文献
130.