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121.
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
122.
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
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124.
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
125.
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
126.
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128.
Katsuaki Mishima Mami Shiraishi Yui Kawai Koji Harada Yoshiya Ueyama 《Oral and maxillofacial surgery》2016,20(2):219-222
Two cases where aberrant tissue was attached to the lower lip mimicking the inferior labial frenum were reported. The frenum-like tissue extended from the gingival margin between the lower left deciduous central and lateral incisors in case 1 and between the lower right deciduous central and lateral incisors in case 2, to the dry lower lip. Histologically, the resected specimen was regarded as normal oral mucosa covered with stratified squamous epithelium, without a clear amniotic band. The frenum-like tissue of the lower lip found in both our patients was diagnosed as a category of oral synechiae, of unknown origin. 相似文献
129.
Sachiro Kakinoki Ji-Hun Seo Yuuki Inoue Kazuhiko Ishihara Nobuhiko Yui 《Journal of biomaterials science. Polymer edition》2013,24(11):1320-1332
Adhesion behaviors of human umbilical vein endothelial cells (HUVECs) are interestingly affected by the mobility of hydrophilic chains on the material surfaces. Surfaces with different molecular mobilities were prepared using ABA-type block copolymers consisting polyrotaxane (PRX) or poly(ethylene glycol) (PEG) central block (A block), and amphiphilic anchoring B blocks of poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB). Two different molecular mobilities of the PRX chains were designed by using normal α-cyclodextrin (α-CD) or α-CD whose hydroxyl groups were converted to methoxy groups in a given ratio to improve its molecular mobility (PRX–PMB and OMe-PRX–PMB). The surface mobility of these materials was assessed as the mobility factor (Mf), which is measured by quartz crystal microbalance with dissipation monitoring system. HUVECs adhered on OMe-PRX–PMB surface much more than PRX–PMB and PMB-block–PEG–block-PMB (PEG–PMB) surfaces. These different HUVEC adhesions were correlated with the density of cell-binding site of adsorbed fibronectin. In addition, the alignment of the actin cytoskeleton of adhered HUVECs was strongly suppressed on the PEG–PMB, PRX–PMB, and OMe-PRX–PMB in response to the increased Mf value. Remarkably, the HUVECs adhered on the OMe-PRX–PMB surface with much less actin organization. We concluded that not only the cell adhesion but also the cellular function are regulated by the molecular mobility of the outmost material surfaces. 相似文献
130.
Yui Ito Mitsuaki Ishida Chisato Ohe Chika Miyasaka Koji Tsuta 《Journal of cutaneous pathology》2021,48(1):102-105
Signet‐ring cell/histiocytoid carcinoma (SRCHC) is a very rare skin appendage cancer, with an extremely rare occurrence in the axilla. This study describes the 11th case of SRCHC occurring in the axilla and reports the first gene alteration analysis performed for SRCHC. An 85‐year‐old Japanese male presented with a tumor in the left axilla. Biopsy of the axilla nodule demonstrated diffuse proliferation of histiocytoid neoplastic cells and signet‐ring cells in the dermis and subcutis. Immunohistochemistry revealed loss of E‐cadherin expression in these neoplastic cells. Accordingly, SRCHC of the axilla was diagnosed. Genetic analysis using next‐generation sequencing demonstrated missense mutation of PIK3CA (c1633G>A, pGlu545Lys) and no CDH1 gene mutation.SRCHC of the axilla is considered equivalent to a histiocytoid variant of invasive lobular breast carcinoma. The present SRCHC case demonstrated a pathogenic PIK3CA mutation, which is observed in invasive lobular carcinoma. Additional large case studies are required to clarify the clinicopathological features and gene alterations in SRCHC of the axilla. 相似文献