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61.
False leukemia-lymphoma cell lines: an update on over 500 cell lines.   总被引:6,自引:0,他引:6  
Human leukemia-lymphoma (LL) cell lines represent an extremely important resource for research in a variety of fields and disciplines. As the cell lines are used as in vitro model systems in lieu of primary cell material, it is crucial that the cells in the culture flasks faithfully correspond to the purported objects of study. Obviously, proper authentication of cell line derivation and precise characterization are indispensable requirements to use as model systems. A number of studies has shown an unacceptable level of LL cell lines to be false. We present here the results of authenticating a comprehensively large sample (n = 550) of LL cell lines mainly by DNA fingerprinting and cytogenetic evaluation. Surprisingly, near-identical incidences (ca 15%) of false cell lines were observed among cell lines obtained directly from original investigators (59/395: 14.9%) and from secondary sources (23/155: 14.8%) implying that most cross-contamination is perpetrated by originators, presumably during establishment. By comparing our data with those published, we were further able to subclassify the false cell lines as (1) virtual: cross-contaminated with and unretrievably overgrown by other cell lines during initiation, never enjoying independent existence; (2) misidentified: cross-contaminated subsequent to establishment so that an original prototype may still exist; or (3) misclassified: unwittingly established from an unintended (often normal) cell type. Prolific classic leukemia cell lines were found to account for the majority of cross-contaminations, eg CCRF-CEM, HL-60, JURKAT, K-562 and U-937. We discuss the impact of cross-contaminations on scientific research, the reluctance of scientists to address the problem, and consider possible solutions. These findings provide a rationale for mandating the procurement of reputably sourced LL cell lines and their regular authentication thereafter.  相似文献   
62.
A 72-year-old Japanese woman, suffering from squamous cell lung cancer with brain metastasis, underwent 2 courses of combination chemotherapy, consisting of cisplatin and vindesine. Although both the primary tumor and the brain metastasis regressed markedly, she developed left ocular pain with blurred vision. An abnormal mass was found in the left iris, and cytologic examination of the aqueous aspirate revealed a few malignant cells, which, when examined by electron microscopy, were considered to be derived from squamous cell carcinoma of the lung.  相似文献   
63.
Amino acid transport system L has been proposed to be one of the major nutrient transport systems at the blood-brain barrier. Using immunohistochemical analyses, a system L transporter LAT1 was shown to be expressed in the brain capillary endothelial cells in rats. Because LAT1 was coexpressed with 4F2 heavy chain which brings LAT1 to the plasma membrane, LAT1 is proposed to be functional in the plasma membrane of brain capillary endothelial cells. Both LAT1 and 4F2hc immunoreactivities were detected in a double line appearance surrounding endothelial cell nuclei, suggesting both proteins are present in the luminal and abluminal membranes. LAT1 is, thus, a blood-brain barrier system L transporter responsible for the permeation of aromatic or branched-chain amino acids and amino acid-related drugs such as L-DOPA.  相似文献   
64.
The proximal isovelocity surface area (PISA) method for calculating volume flow through the regurgitant orifice has attracted significant attention. A number of in vitro studies and clinical studies in adults suggest that the method is accurate. However, when applying the method to children it must be noted that the absolute regurgitation volume is small, and the range of body sizes is wide. This study investigated the accuracy of the PISA method for quantitative assessment of the severity of mitral regurgitation in children. Twenty children aged 7 months to 12 years (average 4.7 years) with mitral regurgitation but without interventricular shunt or aortic stenosis were selected for this study. Underlying cardiac diseases included atrioventricular septal defects in nine, isolated mitral regurgitation in five, and association with other heart defects in six. The PISA radius (r) and the duration of regurgitation (T) were measured on color M-mode recordings, with the M line passing through the center of the PISA. Assuming that the PISA is a hemisphere, maximal regurgitant flow rate (MFR: ml/s) was calculated as MFR = 2π×~ r 2×~ V (r= maximal radius, V= aliasing velocity), and regurgitant stroke volume (RSVpisa) as RSVpisa = 2π×~ MSR ×~ V×~ T (MSR = mean square of the PISA radius during regurgitation). As a validating standard, total stroke volume (TSV) using two-dimensional echocardiography determined by the area–length volumetry method and forward stroke volume (FSV) by the pulsed Doppler method were measured, and regurgitant stroke volume (RSVD: RSVD= TSV − FSV) and regurgitant fraction (RF: RF = RSVD/TSV) were calculated. A linear correlation was found between MFR, RSVpisa, and RSVD (X) (MFR = 4.2X + 54.0, r= 0.84. RSVpisa = 1.0X + 9.8, r= 0.90), and both RSVpisa and MFR divided by body surface area (BSA: m2) revealed a significant correlation with regurgitant fraction (X) by nonlinear regression analysis (RSVpisa/BSA = 26.2 ×~ X/(1 − X) + 16.8, r= 0.85. MFR/BSA = 121.8 ×~ X/(1 − X) + 92.2, r= 0.79). It is concluded that maximal regurgitant flow rate, regurgitant stroke volume, and regurgitant fraction can be accurately predicted in children using the PISA method by Doppler echocardiography.  相似文献   
65.
An extremely rare case of clear cell adenocarcinoma of the uterine cervix in pregnancy is reported. The primary lesion was first found at 34 weeks of pregnancy in a 34-year-old patient, and was cytologically suspected to be malignant. At 39 weeks of pregnancy, the patient underwent abdominal cesarean section concomitantly with removal of huge right ovarian tumor (3050 g) and delivered a normal male baby weighing 3590 g. Histological findings for cone biopsy at 22 days postpartum revealed invasive adenocarcinoma, and abdominal radical hysterectomy and pelvic lymphoadenectomy were performed at 36 days postpartum. Microscopically, the tumor tissue was composed of clear and hobnail-type cells. It showed a considerable amount of PAS-positive diastase-labile glycogen but was only weakly positive for immunoperoxidase staining of carcinoembryonic antigen.  相似文献   
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The outcome after surgical resection for intrahepatic cholangiocarcinoma has not been satisfactorily evaluated due to its malignant behavior. Surgical resection, however, has the potential to improve the prognosis and may allow surgeons to experience rare cases with long survival. This report presents the case of a patient who developed recurrence 9?years after resection of intrahepatic cholangiocarcinoma. A 76-year-old female was diagnosed to have intrahepatic cholangiocarcinoma and underwent an extended right posterior subsegmentectomy. The gross appearance showed a mass-forming type tumor. The histopathological examination revealed well to moderately differentiated adenocarcinoma associated with portal vein invasion. Subcutaneous metastasis in the head as the first sign of relapse was diagnosed 9?years after hepatectomy. The histopathological findings of the subcutaneous tumor were similar to those of the intrahepatic cholangiocarcinoma, thus suggesting metastasis from intrahepatic cholangiocarcinoma. Positron emission tomography with 2-[fluorine-18]-fluoro-2-deoxy-d-glucose was useful for detecting multiple metastases. Long-term follow-up for more than 5?years is recommended because the present case shows that late recurrence of intrahepatic cholangiocarcinoma occurs even 5?years after resection.  相似文献   
70.
Objective The quality of life and activities of daily living (ADL) are generally poor among dialysis patients after intracerebral hemorrhaging, and their precise clinical course remains unclear. In addition, the association between the severity of cerebral hemorrhaging and the long-term prognosis in these patients has not been fully elucidated. This study aimed to evaluate the subsequent prognosis of hemodialysis patients who survived the acute phase of intracerebral hemorrhaging. Methods We included hemodialysis patients who were admitted to Nagasaki University Hospital between 2007 and 2015 for intracerebral hemorrhaging treatment. After excluding cases of in-hospital death, survivors were classified using the 5-point modified Rankin Scale (mRS), which specifically measures the ADL in patients with cerebrovascular diseases. The patients were followed up at the medical facilities to which they were transferred in the same medical zone until 2017. Results Out of 91 patients with cerebral hemorrhaging (65±11 years old, 66% men, hemodialysis duration 108±91 months), 62 survived until discharge. Twenty-one patients died during observation, largely due to infectious diseases, such as sepsis and pneumonia (n=16, 76%). Compared to patients with mRS 0-4 (n=31), those with mRS 5 (n=31) showed a significantly poorer prognosis. The hazard ratio adjusted for age and antiplatelets was 13.7 (95% confidence interval: 3.88-63.7, p<0.001). Conclusion Hemodialysis patients with intracerebral hemorrhaging who were bedridden showed poor outcomes. The major causes of death were infections. Therefore, these patients should be carefully monitored for infections in order to improve their prognosis.  相似文献   
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