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81.
We investigated relationships between DNA copy number aberrations and chromosomal structural rearrangements in 11 different cell lines derived from oral squamous cell carcinoma (OSCC) by comparative genomic hybridization (CGH), spectral karyotyping (SKY), and fluorescence in situ hybridization (FISH). CGH frequently showed recurrent chromosomal gains of 5p, 20q12, 8q23 approximately qter, 20p11 approximately p12, 7p15, 11p13 approximately p14, and 14q21, as well as losses of 4q, 18q, 4p11 approximately p15, 19p13, 8p21 approximately pter, and 16p11 approximately p12. SKY identified the following recurrent chromosomal abnormalities: i(5)(p10), i(5)(q10), i(8)(q10), der(X;1)(q10;p10), der(3;5)(p10;p10), and der(3;18)(q10;p10). In addition, breakpoints detected by SKY were clustered in 11q13 and around centromeric regions, including 5p10/q10, 3p10/q10, 8p10/q10 14q10, 1p10/1q10, and 16p10/16q10. Cell lines with i(5)(p10) and i(8)(q10) showed gains of the entire chromosome arms of 5p and 8q by CGH. Moreover, breakages near the centromeres of chromosomes 5 and 8 may be associated with 5p gain, 8q gain, and 8p loss in OSCC. FISH with a DNA probe from a BAC clone mapping to 5p15 showed a significant correlation between the average numbers of i(5)(p10) and 5p15 (R(2) = 0.8693, P< 0.01) in these cell lines, indicating that DNA copy number of 5p depends upon isochromosome formation in OSCC.  相似文献   
82.
H2AX is a histone H2A variant that becomes phosphorylated upon genotoxic stress. The phosphorylated H2AX (γ-H2AX) plays an antioncogenic role in the DNA damage response and its foci patterns are highly variable, in terms of intensities and sizes. However, whether characteristic γ-H2AX foci patterns are associated with oncogenesis (oncogenic-specific γ-H2AX foci patterns) remains unknown. We previously reported that a defect in the acetyltransferase activity of TIP60 promotes cancer cell growth in human cell lines. In this study, we compared γ-H2AX foci patterns between TIP60 wild-type cells and TIP60 HAT mutant cells by using machine learning. When focused solely on the intensity and size of γ-H2AX foci, we extracted the TIP60 HAT mutant-like oncogenic-specific γ-H2AX foci pattern among all datasets of γ-H2AX foci patterns. Furthermore, by using the dimensionality reduction method UMAP, we also observed TIP60 HAT mutant-like oncogenic-specific γ-H2AX foci patterns in TIP60 wild-type cells. In summary, we propose the existence of an oncogenic-specific γ-H2AX foci pattern and the importance of a machine learning approach to extract oncogenic signaling among the γ-H2AX foci variations.  相似文献   
83.
In the prior two reports, we demonstrated that G-CSF induced the polarization of neutrophils by itself, and also enhanced superoxide production from neutrophils stimulated by the chemotactic peptides. In this study, we have examined the protective effect of G-CSF in vivo on Pseudomonas pneumonia and septicemia in mice. Cyclophosphamide (CY) induced severe reduction of the number of peripheral leukocytes and weakened resistance for Psuedomonas aeruguinosa infection of mice. However, in mice receiving recombinant human G-CSF four daily subcutaneous injection, the number of leukocytes, particulary neutrophils, increased more rapidly than in controls receiving saline. Moreover G-CSF enhanced a protective effect to pulmonary and systemic pseudomonas infections. When G-CSF was administered together with antibiotics, significant synergism in the protection against pulmonary infection of Pseudomonas was observed. Carrageenan treatment decreased the protective effect of G-CSF. These results suggested that the protective effect of G-CSF against P. aeruginosa infection depends not only on PMN but also another complexed host defence mechanism.  相似文献   
84.
Full‐arch screw‐retained implant‐supported fixed dental prostheses have a high long‐term success rate and are considered the gold standard by many clinicians. However, accurate fabrication of a passive fit long‐span prosthesis can be challenging. A novel intraoral adhesion method using galvano‐telescopic copings was proposed as a way of improving prosthetic fit for edentulous patients. This report describes the treatment of a 74‐year‐old female with a full‐arch implant‐supported dental prosthesis, supported by a combination of galvano‐telescopic copings and screws to prevent retention loss. Four years have passed since this superstructure was placed, during this time she exhibited a good clinical course with no inflammation noted in surrounding tissues. Treatment with an implant‐supported fixed dental prosthesis, retained by a combination of galvano‐telescopic copings and screws, can be a useful alternative treatment for edentulous patients.  相似文献   
85.
86.
In the developed countries, especially Japan, elderly population is rapidly increasing, but outcomes of elderly patients with the age of 80 years and older suffering from subarachnoid hemorrhage (SAH) remain still unclear. We retrospectively reviewed the medical records of nontraumatic SAH patients aged 80 years and older, who were hospitalized in a single center between 1998 and 2009. There were 28 patients (80-90 years old and 75% female), representing 5.9% of all non-traumatic SAHs (n = 474). Of those, 16 patients received an intervention (ten clipping and six endovascular coiling) and the remaining 12 patients were managed conservatively. The median survival time of intervention group was 110 days and that of conservative group 49 days (p = 0.12, log rank analysis). Cox's proportional hazards model yielded two variables, the Japan Coma Scale (JCS) grade on admission ( hazard ratio: 2.93 [p = 0.009]) and conservative treatment (hazard ratio: 2.14 [p = 0.054]). In the outcome of the modified Rankin Scale between these two groups, logistic regression analysis had significant variable; the JCS grade on admission (odds ratio: 280, [p = 0.020]). In the elderly patients with good initial clinical condition, an acute intervention may have good outcome.  相似文献   
87.
88.
Hereditary leiomyomatosis and renal cell cancer is a rare genetic disorder characterized by cutaneous and uterine leiomyomatosis, and an aggressive type 2 papillary renal cell carcinoma. The disease is caused by a germline mutation in the fumarate hydratase gene. We report a familial hereditary leiomyomatosis and renal cell cancer in two siblings. A 34‐year‐old woman underwent nephrectomy for treatment of a renal cell carcinoma. The patient's sister had been diagnosed with renal cell carcinoma at 28 years‐of‐age and died of the disease. Neither sister had apparent skin tumors. Histopathology of the renal cell carcinomas of the siblings showed tubulocystic and papillary architectures with high nuclear grades. Immunostaining showed no fumarate hydratase expression in either tumor. Genomic DNA sequencing of the patient showed a germline mutation in the fumarate hydratase gene (c.675delT). Although there is no epidemiological information on Asian hereditary leiomyomatosis and renal cell cancer, physicians should be aware that typical cutaneous leiomyomatosis might not always be present in patients with hereditary leiomyomatosis and renal cell cancer.  相似文献   
89.
PURPOSE: It is ideal to use not a transperitoneal but a retroperitoneal approach for both open and endoscopic partial nephrectomy. We compared the results of retroperitoneoscopic nephron-sparing surgery for small renal tumors using a microwave tissue coagulator without renal pedicle clamping with those of a retroperitoneal open procedure. PATIENTS AND METHODS: Between 1996 and 2002, eight patients with small renal tumors underwent retroperitoneoscopic partial nephrectomy without renal ischemia, and nine patients with small renal tumors underwent open partial nephrectomy via a retroperitoneal approach. Both groups were operated on using a microwave tissue coagulator. RESULTS: Retroperitoneoscopic partial nephrectomy without renal ischemia was performed without any major or minor complications in any patient. The mean operation time for retroperitoneoscopic surgery was significantly longer than that for open partial nephrectomy (221.9 minutes v 145.9 minutes; P = 0.0004). However, the mean estimated blood loss for retroperitoneoscopic surgery was less than that for open partial nephrectomy (137.5 mL v 334.8 mL; P = 0.012). In addition, the retroperitoneoscopic group seemed to recover more rapidly than the open surgery group. CONCLUSIONS: Retroperitoneoscopic nephron-sparing surgery of small renal tumors using a microwave tissue coagulator without renal ischemia is feasible as minimally invasive procedure. It results in saving renal function, minimal blood loss, and rapid recovery.  相似文献   
90.
PURPOSE: The purpose of this study was to evaluate the usefulness of CT or MR imaging findings in patients with spinal epidural hematoma (SEH) for predicting neurological outcome. MATERIALS AND METHODS: MR images of our six patients with SEH were evaluated retrospectively: complete recovery was achieved in two patients; paresis remained in two patients; and paraplegia remained in two patients. The ratio of the maximum anteroposterior diameter of the SEH to that of the spinal canal was calculated in each patient on midline on axial images in our six patients and 23 previously reported patients. RESULTS: Among our six patients, the ratio was less than 60% in two patients with total recovery, whereas all four patients with remaining motor impairment had ratios of 60% or more. Of 29 cases, 18 of 22 patients without residual motor impairment had ratios of less than 60%, but five of seven patients with residual motor deficits had ratios of 60% or more (p = 0.023). CONCLUSION: The degree of spinal cord compression by hematoma may be a prognostic factor in SEH.  相似文献   
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