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61.
A 13-year-old boy, with a history of intermittent headache and transient diplopia, was found to have non-hemorrhagic cerebral arteriovenous malformation in the midbrain tegmental region associated with hydrocephalus. Gamma knife radiosurgery was performed at 16 Gy with 75% marginal dose. Posttreatment course was uneventful. Follow-up MR imaging at one year after the treatment revealed complete disappearance of the abnormal vascular flow voids. The size of each ventricle at the treatment and at one year after treatment were as follows; 60.2 cc and 20.9 cc in the lateral ventricles, 3.7 cc and 2.7 cc in the third ventricle. The hydrocephalus might be caused by obstructive mechanism but mostly by high venous pressure due to the shunt blood flow. The goal of treatment for hydrocephalus should be nidus obstruction and normalizing the vascular flow.  相似文献   
62.
Prosaposin is the precursor of four glycoprotein activators (saposins) for lysosomal hydrolases. Intact prosaposin also has lipid transfer properties in vitro as well as neuritogenic effects ex vivo and in vivo. Such "neuritogenic" effects of saposin C were evaluated in vivo using transgenic mice with prosaposin cDNAs having normal (PS-N) or mutated neuritogenic region. The mutant prosaposin cDNA (PS-CBC) encoded a chimeric saposin C that contained the non-neuritogenic sequence of saposin B, but retained acid beta-glucosidase (GCase) activation effects. When driven by the PGK (3-phosphoglycerate kinase) promoter, transgene expression was highest in the cerebrum for any of the transgenes (range from 15% to 42% of wild-type). Low levels were in visceral tissues. Prosaposin knock-out (PS-/-) mice expressing N or CBC transgenes, even at low levels, had delayed onset of neurologic signs and neuropathology, and significant lengthening of life span (from 1.7- to 7-fold) with age dependent partial correction of GlcCer and LacCer accumulation in the brain. Neuropathologic progression and neuronal glycosphingolipid storage were related directly to the transgene expression levels in the brain. Purkinje cell loss was age dependent. Gross brain and neuronal organizations were indistinguishable in PS-/- mice with or without the various transgenes, albeit the phenotype appeared later in the mice with transgenes. These studies show the degree of neuropathologic manifestations in each transgenic line depended on expression level rather than on the nature of the transgene. These studies also show in vivo localization of the GCase activation region to the carboxy terminal half of saposin C and the lack of a significant gross trophic effect of saposin C on CNS organization in vivo.  相似文献   
63.
Mucinous cystadenoma of the appendix is a type of appendiceal mucocele and a rather rare condition usually found incidentally in the course of other abdominal surgery. A previous evaluation of 73 appendiceal mucoceles showed that this disease was often associated with adenocarcinoma and other epithelial atypia. This observation suggested that patients with mucinous cystadenoma of the appendix also have some underlying disorders. However, non-epithelial changes associated with appendiceal mucocele have not been reported so far. In this study, we presented for the first time a mucinous cystadenoma of the appendix associated with muscular and neuromatous hyperplasia.  相似文献   
64.
ObjectivesTo compare the clinical outcomes of sigmoid and ileal neobladders (NBs) created following radical cystectomy.Materials and methodsThis study included 90 and 144 Japanese patients undergoing radical cystectomy and orthotopic NB reconstruction with a sigmoid and ileal segment, respectively. Postoperative clinical outcomes between the sigmoid and ileal NB groups (SNBG and INBG) were compared.ResultsIn this series, 110 early and 51 late complications occurred in 71 and 41 patients, respectively; however, there was no significant difference in the incidence of complications between SNBG and INBG. At 1 year postoperatively, there were no significant differences in the proportion of spontaneous voiders and the continence status between these 2 groups; however, despite the lack of significant differences in the maximal flow rate and voided volume, the post-void residual in SNBG was significantly smaller than that in INBG. Voiding functional outcomes at 5 years postoperatively were also obtained from 28 and 49 in SNBG and INBG, respectively. Although there were no significant changes in the functional outcomes in SNBG, the proportion of spontaneous voiders and post-void residual in INBG at 5 years postoperatively were significantly poorer than those at 1 year postoperatively. Furthermore, the postoperative health-related quality of life assessed by a Short-Form 36 survey did not show any significant differences in all 8 scores between these 2 groups.ConclusionsBoth types of NB reconstruction resulted in comparatively satisfactory outcomes; however, the voiding function, particularly that on long-term follow-up, in SNBG appeared to be more favorable than that in INBG.  相似文献   
65.
66.
In order to demonstrate possible roles of retrodifferentiation in relapses after differentiation therapies, we have established a retrodifferentiated cell line (RD-1) from a single rat myelomonocytic leukemia cell which differentiated into a macrophage-like cell by treatment with lipopolysaccharide (LPS). The established RD-1 cells showed microscopic features slightly maturer than their parent cells. The RD-1 cells had the ability to differentiate into macrophage-like cells by treatment with fewer doses of LPS than those for parent cells. All rats inoculated with the parent cells (more than 102/rat) died within 50 days. Rats inoculated with 104 RD-1 cells survived for more than 120 days, whereas two out of four rats inoculated with 105 cells and all the rats inoculated with 5 × 105 cells died of leukemia. These results suggest that RD-1 cells are retrodifferentiated cells from a single rat myelomonocytic leukemia cell which differentiated into a macrophage-like cell; they have similar phenotypes and lower tumorigenicity than the parent cells and they also suggest that the appearance of retrodifferentiated leukemia cells may be responsible for relapse after differentiation therapy for leukemia in some cases.  相似文献   
67.
Sodium d -glucaro-δ-lactam (ND2001) inhibited spontaneous pulmonary metastases of the highly metastatic B16 melanoma variant with a maximal inhibition rate of 99.5%, and 6 of 7 animals remained metastasis-free. Likewise, ND2001 inhibited the spontaneous pulmonary metastases of both Lewis lung carcinoma (3LL) with a rate of 98.0% (3 of 5 animals remaining metastasis-free) and rat KDH-8 liver carcinoma with a rate of 82.5% (3 of 7 animals remaining metastasis-free), although it was unable to inhibit the metastases of mouse BMT-11 fibrosarcoma and rat SST-2 breast carcinoma. Pretreatment with ND2001 in vitro inhibited the pulmonary metastases of the B16 variant and 3LL cells, which indicates direct action upon the cancer cells. When the invasive activity of cancer cells was measured by the Boyden chamber method, the number of invading B16 variant or 3LL cells was reduced with maximal inhibition rates of 93.0% or 89.9%, respectively, but pretreatment with ND2001 failed to reduce the invasive activity of BMT-11 or SST-2 cells. ND2001 showed neither cytocidal nor antitumor activity. These results suggest that ND2001 inhibited pulmonary metastases at the invasive step into the basement membrane by directly changing some property of the tumor cells.  相似文献   
68.
We have investigated the inhibitory effect of oral administration of Juzen-taiho-to , a Kampo (Chinese herbal) medicine, on progressive growth of a mouse fibrosarcoma. Spontaneously regressive QR-32 tumor cells were able to grow progressively in vivo when coimplanted s.c. with a foreign body, gelatin sponge, whereas QR-32 cells alone gradually grew for over 15 days after inoculation and thereafter regressed for up to 25 days. Oral administration of Juzen-taiho-to (40 mg/day/mouse) for 7 days after inoculation of QR-32 cells with gelatin sponge resulted in significant inhibition of tumor growth and prolongation of the survival of the tumor-bearing mice. This growth-inhibitory effect of Juzen-taiho-to observed on day 25 was dose-dependent over the dose range from 4 to 40 mg/day. Treatment with Juzen-taiho-to for 7 days before tumor inoculation with gelatin sponge also significantly suppressed tumor growth examined on day 25, as did the administration of bismuth subnitrate, which is well known to induce metallothionein, an antioxidant. On the other hand, inoculation of progressed tumor cells (QRsP) resulted in growth without gelatin sponge, leading to death in syngeneic mice. Administration of Juzen-taiho-to for 7 days after inoculation of QRsP cells resulted in a decrease of the tumor growth and prolongation of the survival of mice, but the effect was less than that on the growth of QR-32 regressor tumor after coimplantation with gelatin sponge. These results suggest that the inhibitory effect of Juzen-taiho-to is partly associated with prevention of gelatin sponge-elicited progressive growth, probably mediated by endogenous factors including antioxidant substances, in addition to the augmentation of host-mediated antitumor activity.  相似文献   
69.
A 7-year-old boy with sex-linked agammaglobulinaemia developed meningoencephalitis caused by echovirus type 11. He had convulsions, right hemiplegia, cortical motor aphasia, left abducens nerve paralysis, left hypoglossal nerve paralysis, and later became unconscious. Treatment by intravenous injection of conventional gammaglobulin and intrathecal alpha-interferon brought no clinical improvement, but intrathecal administration together with intravenous injection of gammaglobulin containing a high titre of anti-echovirus type 11 antibody was assciated with a dramatic improvement in his clinical symptoms. After subsequent periodical (once or twice a week) administration of specific gammaglobulin for 8 months, the echovirus in his cerebrospinal fluid was no longer detected. These findings suggest that intrathecal injection combined with intravenous injection of high titre antiechovirus type 11 antibodywas effective in treating this case of echovirus meningoencephalitis in sex-linked agammaglobulinaemia.  相似文献   
70.
Surgical treatment of brainstem lesions has been encouraged after the development of magnetic resonance imaging. However, direct approaches to intra-axial lesions in the brainstem still carry a high risk of morbidity because the neuronal structures can be injured along the entry routes. We present two patients whose pontine cavernous angiomas were removed via incision of the lateral aspect of the pons with presigmoid approach. The first case, a 41-year-old woman, presented with paresis of the cranial nerves VI, VII, and VIII, and left hemiparesis progressing over 2 weeks caused by a cavernous angioma ventrally located in the lower pons. The second case, a 50-year-old woman, developed dizziness over 2 months due to a large cavernous angioma in the center of the pons. These lesions were totally removed through the presigmoid approach and no additional neurological deficits were observed. An image-guided navigation system was used for the craniotomy and removal of the lesion in the second patient. The presigmoid approach provides a safe route to intra-axial lesions in the pons. A technique for presigmoid craniotomy with one-piece bone flap under the image-guided navigation is also described.  相似文献   
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