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91.
OBJECTIVE AND IMPORTANCE: A type of intrinsic dorsal midbrain glioma known as benign tectal glioma can cause obstructive hydrocephalus. Because of its slow progress and relatively good prognosis, initial treatment should be cerebrospinal fluid diversion and biopsy. CLINICAL PRESENTATION: We report a 24-year-old man with obstructive hydrocephalus from a tectal glioma, who was admitted to the hospital for malfunction of a shunt placed 16 years previously. INTERVENTION: Magnetic resonance imaging demonstrated enlargement of the dorsal midbrain associated with increased signal intensity on T2-weighted images and fluid attenuation inversion recovery (FLAIR) images. No enhancement occurred with contrast administration. We performed a neuroendoscopic third ventriculostomy and biopsy of the tumor. Histologic examination of the specimen obtained disclosed a low-grade astrocytoma. No postoperative neurologic complications occurred. CONCLUSION: FLAIR images were superior to T2-weighted images in demonstrating abnormal intensity in the dorsal midbrain. Neuroendoscopy confirmed a yellowish tumor inferior to the posterior commissure occluding the entrance of the aqueduct, an observation useful in planning biopsy of the lesion. As the tumor apparently had existed for a number of years, the case supports the notion that the prognosis associated with these tumors is good.  相似文献   
92.
Abstract

Leukotriene has been proposed as a factor of tumour induced brain oedema. Independently of its size, meningioma occasionally shows various extents of peritumoural oedema. We investigated LTC4 tissue contentsLTC4 catabolic and synthetic activity in 12 human meningiomas and their correlation with peritumoural oedema was studied. LTC4 contents were varied from 0.01 to 8.21 pg/mg tissue. When LTA4/ an unstable expoxide intermediate was incubated with tumour homogenate, LTC4 was rapidly synthesized. However; LTC4 levels generated by incubating LTA4 with each homogenate were much different in each case. Degradation of LTC4 to LTD4, LTE4, and other polar materials was also rapid by incubation with tumour homogenates. Approximately 70% of added UC4 was transformed to LTD4/ LTE4 nor 6-trans LTB4 diastereoisomers during 30 min incubation at 37 °C. The results suggested that there were significant LTC4 tissue contents and LTC4 synthetic and catabolic activity in meningiomas. Oedema index ranged from 1.0 (no peritumoural oedema) to 67.5. No significant correlationi, however', was observed not only between the LTC4 tissue contents and LTC4 synthetic or catabolic activities but also between each of these three parameters and peritumoural oedema. Thus, these results do not support a significant correlation of sulfidopeptide LTs with oedema formation in meningioma patients. Since leukotrienes are extremely unstable compounds, LTC4 tissue contents should be carefully discussed along with a consideration of rapid LTC4 synthesis and catabolism. Further role of leukotrienes in meningioma tissue should be studied.  相似文献   
93.
Hidroacanthoma simplex (HAS) is a rare benign eccrine adnexal tumor. HAS is sometimes clinically or pathologically misdiagnosed as squamous cell carcinoma in situ (Bowen's disease; BD), seborrheic keratosis (SK) or other adnexal tumor. To date, there has never been a report focusing on dermoscopic features to distinguish HAS from BD and SK. We found the following dermoscopic findings to be characteristic of HAS: fine black dots/globules (75% of cases) and fine scales arranged annularly (100% of cases). In contrast, glomerular vessels, which are typically observed in BD, were not seen in any of the four cases. Cerebriform appearance and milia‐like cysts, which are typically observed in SK, were also not seen in any of the four cases. The existence of “scattered fine black dots/globules” and “fine scales arranged annularly”, and the absence of the glomerular vessels, may contribute to precise diagnosis of HAS. Even though HAS resembles BD or SK clinically, it can be distinguished from these by the characteristic dermoscopic features.  相似文献   
94.
Surgical results of 81 cases with various benign thyroid tumors were reviewed. All had undergone mainly hemi-lobectomy including isthmectomy and had been followed up for more than 2 years. Sixty-eight (84%) have been well without any complaint. However, 5 of 15 cases with adenomatous goiter (AG) again developed nodule(s) in the remnant thyroid and 1 of 37 cases with adenoma developed cancer in the remnant. In order to prevent recurrence in the cases with AG, total thyroidectomy may be required with the meticulous selection of the case. For the cases with AG which undergone hemilobectomy or lumpectomy, TSH suppression treatment may be also required after surgery. It is of caution that the nodule developed in the thyroid after surgery may be not always the same nodule as primary one.  相似文献   
95.
Tumor suppressor gene p53 is a critical regulator of the cellular response to DNA damage. To examine the function of p53 in postmitotic CNS neurons, we cultured cerebellar granule cells from 15-day-old wild type and p53-deficient mice, and analyzed changes of protein expression in apoptosis elicited by DNA damage. When cerebellar granule cells from wild type mice were treated with bleomycin, a DNA strand-break inducing agent, neuronal death occurred. In contrast, cells from p53-deficient mice were resistant to bleomycin-induced neuronal death. Furthermore, cells from p53 heterozygous mice showed an intermediate resistance between wild type and p53-deficient mice. These results show that p53 is required for the bleomycin-induced cerebellar granule cell death. To examine which proteins are involved in this apoptosis, we examined changes in protein levels of the Bcl-2 family, including Bcl-2, Bcl-X and Bax. The relative amounts of these proteins did not change after bleomycin treatment, suggesting that the changes in the levels of these Bcl-2 family proteins are not necessary for apoptosis in this system. In contrast, the levels of c-Jun protein significantly increased 6 h after treatment with bleomycin in wild type but not in p53-deficient cerebellar granule cells. These results raise the possibility that c-Jun is required for p53-dependent neuronal apoptosis induced by bleomycin.  相似文献   
96.
Transmembrane AMPA receptor regulatory proteins (TARPs), including stargazin/gamma-2, are associated with AMPA receptors and participate in their surface delivery and anchoring at the postsynaptic membrane. TARPs may also act as a positive modulator of the AMPA receptor ion channel function; however, little is known about other TARP members except for stargazin/gamma-2. We examined the synaptic localization of stargazin/gamma-2 and gamma-8 by immunoelectron microscopy and biochemical analysis. The analysis of sodium dodecyl sulfate-digested freeze-fracture replica labeling revealed that stargazin/gamma-2 was concentrated in the postsynaptic area, whereas gamma-8 was distributed both in synaptic and extra-synaptic plasma membranes of the hippocampal neuron. When a synaptic plasma membrane-enriched brain fraction was treated with Triton X-100 and separated by sucrose density gradient ultracentrifugation, a large proportion of NMDA receptor and stargazin/gamma-2 was accumulated in raft-enriched fractions, whereas AMPA receptor and gamma-8 were distributed in both the raft-enriched fractions and other Triton-insoluble fractions. Phosphorylation of stargazin/gamma-2 and gamma-8 was regulated by different sets of kinases and phosphatases in cultured cortical neurons. These results suggested that stargazin/gamma-2 and gamma-8 have distinct roles in postsynaptic membranes under the regulation of different intracellular signaling pathways.  相似文献   
97.
The genome of a subset of non-small-cell lung cancers (NSCLC) harbors a small inversion within chromosome 2 that gives rise to a transforming fusion gene, EML4-ALK, which encodes an activated protein tyrosine kinase. Although breakpoints within EML4 have been identified in introns 13 and 20, giving rise to variants 1 and 2, respectively, of EML4-ALK, it has remained unclear whether other isoforms of the fusion gene are present in NSCLC cells. We have now screened NSCLC specimens for other in-frame fusion cDNAs that contain both EML4 and ALK sequences. Two slightly different fusion cDNAs in which exon 6 of EML4 was joined to exon 20 of ALK were each identified in two individuals of the cohort. Whereas one cDNA contained only exons 1 to 6 of EML4 (variant 3a), the other also contained an additional 33-bp sequence derived from intron 6 of EML4 (variant 3b). The protein encoded by the latter cDNA thus contained an insertion of 11 amino acids between the EML4 and ALK sequences of that encoded by the former. Both variants 3a and 3b of EML4-ALK exhibited marked transforming activity in vitro as well as oncogenic activity in vivo. A lung cancer cell line expressing endogenous variant 3 of EML4-ALK underwent cell death on exposure to a specific inhibitor of ALK catalytic activity. These data increase the frequency of EML4-ALK-positive NSCLC tumors and bolster the clinical relevance of this oncogenic kinase.  相似文献   
98.
Higher body mass index (BMI), higher body adiposity and obesity have been associated with increased risk of colorectal cancer. Evidence suggests that excess energy balance may influence systemic immune and inflammatory status. Thus, we hypothesized that the positive association between BMI and colorectal cancer risk might differ according to colorectal carcinoma subtypes according to levels of histopathological lymphocytic reaction to tumor. We collected biennial questionnaire data on weight and baseline height information in two prospective cohort studies, the Nurses' Health Study (1980‐2010) and the Health Professionals Follow‐up Study (1986‐2010). Utilizing duplication‐method Cox proportional hazards regression models, we prospectively assessed the association between BMI and risk of colorectal cancer subtypes according to the degree of Crohn's‐like lymphoid reaction, peritumoral lymphocytic reaction, intratumoral periglandular reaction, tumor‐infiltrating lymphocytes, the overall lymphocytic reaction score, or T‐cell [CD3+, CD8+, CD45RO (PTPRC)+ or FOXP3+] density in tumor tissue. Statistical significance level was adjusted for multiple hypotheses testing by Bonferroni correction. During follow up of 1,708,029 men and women (over 3,346,752 person‐years), we documented 1,436 incident rectal and colon cancer cases with available formalin‐fixed paraffin‐embedded tumor tissue materials and pathological immunity data. BMI was significantly associated with higher risk of overall colorectal cancer (Ptrend < 0.001); however, the association of BMI with colorectal carcinoma risk did not significantly differ by the level of lymphocytic reaction or T‐cell infiltration in tumor tissue status (Pheterogeneity > 0.10). BMI may be associated with risk of colorectal cancer regardless of levels of lymphocytic response to tumor.  相似文献   
99.
The case was a Japanese man of 62 years old. A bulbar mass attached to mitral valve anterior leaflet was discovered in an echocardiography within detailed examination of ischemic heart disease accidentally. We diagnosed him as ischemic heart disease and doubt of heart tumor. We thought about the danger of future embolism, surgical treatment was decided. We dissected the tumor together with one chorda tendineae of mitral valve, and a performed aorta - coronary bypass surgery. We diagnosed the tumor as papillary fibroelastoma by pathological diagnosis. Papillary fibroelastoma is extremely rare with 7-9% of benign tumor of heart primary. Most of the papillary fibroelastoma is incidentally discovered by echocardiography or autopsy. Or it is discovered for systemic embolism. The tumor is benign, but there is a problem to cause embolism. Therefore, when we discovered papillary fibroelastoma, surgical resection of the tumor is the first-line therapy. A problem on surgical therapy is the range of resection area. Papillary fibroelastoma is benign tumor, but the pathological characteristic is still unidentified. Further epidemiological and pathological studies are necessary to determine the extent of surgical excision in associated with characteristics of papillary fibroelastoma.  相似文献   
100.
To reconstruct the aortic root for aneurysm of the ascending aorta accompanied by aortic regurgitation, annuloaortic ectasia (AAE) and acute type-A dissection with root destruction, the Bentall operation using a prosthetic valve still is the standard procedure today. Valve-sparing procedures have actively been used for aortic root lesions, and have also been attempted in aortic root reconstruction for Marfan syndrome which may have abnormalities in the valve leaflets. We conducted a valve-sparing procedure in a female patient with Marfan syndrome who had AAE accompanied by type-A acute aortic dissection. The patient was a 37-year-old woman complaining of severe pain from the chest to the back. The limbs were long, and funnel breast was observed. Diastolic murmurs were heard. On chest computed tomography, a dissection cavity was present from the ascending aorta to the left common iliac artery, and the root dilated to 55 mm. Grade II aortic regurgitation was observed on ultrasound cardiography. Regarding her family history, her father had died suddenly at 54 years of age. She was diagnosed with type-A acute dissection concurrent with Marfan syndrome and AAE. The structure of the aortic valve was normal, and root reconstruction by a valve-sparing operation and total replacement of the aortic arch was conducted. On postoperative ultrasound cardiography, the aortic regurgitation was within the allowable range, and the shortterm postoperative results were good.  相似文献   
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