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71.
OBJECTIVE: Cell adhesion is an important cell survival determinant and disruption of integrin-mediated signal transduction may be involved in anchorage-dependent cell death. We have examined the processing of focal adhesion kinase (FAK), a component of integrin-mediated signal transduction, in a cisplatin-sensitive human ovarian epithelial cancer cell line (OV2008), to test the possible role of FAK degradation in the control of apoptosis via regulation of cell attachment. METHODS: FAK processing after cisplatin treatment in the absence or presence of various caspase-inhibiting substances was analyzed by Western blot. Caspase-inhibiting activities were introduced using cell-permeable peptides or adenoviral vector. RESULTS: Cisplatin-induced caspase 3 and FAK cleavage, cell detachment from the growth surface, and apoptosis in a temporally related and concentration-dependent manner. FAK fragments were detected exclusively in cells detached from the culture surface. Addition of active caspase 3 to the whole cell lysate elicited a similar pattern of FAK cleavage. Pretreatment of whole cell lysates and cells with tetrapeptide inhibitors of caspases significantly decreased FAK cleavage induced by exogenous active caspase 3 and cisplatin, respectively. Overexpression of X-linked inhibitor of apoptosis protein (Xiap), an endogenous caspase inhibitor, attenuated the cisplatin-induced FAK processing, morphologic changes, and apoptosis. The inhibitory action of Xiap was abolished with the deletion of a functional motif required for caspase inhibition. CONCLUSION: These findings are consistent with our hypothesis that FAK processing is in part mediated by caspase 3, the activation of which is modulated by Xiap.  相似文献   
72.
In mammals, zona pellucida glycoprotein-3 (ZP3) is the putative ligand for primary sperm binding and induces the acrosome reaction. Recent evidence suggests that zona pellucida glycoprotein-1 (ZP1) also play an important role, in some species, during fertilization. In order to identify synthetic peptide immunogens capable of inducing antibodies reactive with native zona and inhibiting sperm-oocyte interaction, peptide encompassing the amino acid (aa) residues 334-343 of bonnet monkey ZP3 (bmZP3) was synthesized co-linearly with a 'promiscuous' T-cell epitope of circumsporozoite protein (CSP, 378-398 aa) of Plasmodium falciparum. In addition, four peptides corresponding to bonnet monkey ZP1 (bmZP1((58-79 aa)), bmZP1((136-153 aa)), bmZP1((212-228 aa)) and bmZP1((251-273 aa))) were synthesized. The synthetic peptides corresponding to bmZP1 were conjugated with diphtheria toxoid. Immunization of female BALB/cJ mice with the above conjugates and CSP-bmZP3((334-343 aa)) peptide led to the generation of an adequate antibody response against the respective zona peptide. Antibodies against bmZP1((251-273 aa)) and CSP-bmZP3((334-343 aa)) recognized bonnet monkey and human zona pellucida in an indirect immunofluorescence assay. Further, these antibodies when tested independently or in combination also significantly inhibited the binding of human spermatozoa to zona pellucida in a hemizona assay. These studies will further help in the design of synthetic peptide immunogens comprising of multiple B cell epitope from different zona proteins for better immunocontraceptive efficacy.  相似文献   
73.
Ovarian tissue banking is a feasible strategy for fertility preservation for young women after cancer treatments. Ovarian tissue, after thawing, is used for several options; orthotopic grafting (normal site), autologous heterotopic grafting and collection of ovarian follicles for culture. Recent reports of live birth encouraged clinicians and researchers to apply this technology to premature ovarian failure (POF) resulting from strong cancer therapy. Grafting, however, carries a risk of malignant cell recurrence. For safety, development of a culture method is necessary but optimum culturing conditions for less-developed follicles abundant in the ovary are not well known. In the present article, the current status of ovarian tissue cryopreservation, and in vitro oocyte growth and maturation from the preserved ovaries are reviewed.  相似文献   
74.
To overcome limited maneuverability and procedures in the endoscopic neurosurgery, and to utilize its maximum potential ability, the HUMAN (hyper-utility mechatronic assistant) system has been developed. The system has a rigid three-dimensional endoscope with built-in three guiding-manipulators completely controlled as a slave robot by a surgeon in a remote place. To use this system most efficiently, we investigated the suitable distance between an object lens of the endoscope and a target. Actual working territory (AWT) and actual working angle (AWA) of the forceps in the endoscopical operative field (EOF) were measured by changing the distance between the lens and the target. AWT ratio (AWT/EOF) and AWA ratio (AWA/360) decreased from 58% to 12% and increased from 39% to 85% respectively as the distance became longer. When the distance exceeds 13 mm, AWA did not increase more than 85%, and AWT kept decreasing. For the effective use of the system, the optimal distance between the lens and the target should be within 13 mm, and the system will demonstrate its ability to the maximum at the distance of 8mm.  相似文献   
75.
76.
A 70-year-old man with poorly controlled diabetes mellitus, and an elevated serum prostatic specific antigen, underwent transrectal prostate biopsy. He received one dose of cefotium before, and three doses of cefotium (1.0 gram every 12 hours intravenously) after prostatic biopsy. He was doing well until postbiopsy day 1, when he developed high fever, dysuria and lower abdominal pain. His perineal area exhibited black-purpish discoloration. On postbiopsy day 3, laboratory data showed leukopenia and DIC. Operative findings during laparotomy on the same day, included malodorous cloudy fluid and tissue edema involving the perivesical space. Intraoperative tissue cultures as well as postoperative cultures of blood and drainage revealed Escherichia coli, serotype O-6. Despite maximal supportive therapy, the patient developed multiorgan failure and died on the tenth postbiopsy day. This patient's history and hospitalization course suggests that transrectal prostatic biopsy induced Fournier's gangrene.  相似文献   
77.
A 56-year-old Japanese man in whom a descending colon carcinomahad been resected underwent a high orchitectomy for metastaticepididymis from the colon. Metastatic carcinoma from the digestiveorgans to the spermatic cord (SC) and/or the intrascrotal contents(ISC) is rare. Fifty-four Japanese patients with metastasisfrom the digestive organs to the SC and/or the ISC were analyzed.The most frequent primary site was the stomach and the mostfrequent metastatic site was the spermatic cord. Our patientwas the first to exhibit metastasis from the colon to the epididymis.A primary site was identified in 24 patients subsequent to themetastatic tumor. Twenty patients had other organ metastatis.The prognosis for SC and/or ISC metastasis patients is poor.Our patients has survived for 18 months following his orchitectomywith no other organ metastasis (31 months after the primaryoperation). In our patient, monoclonal estrogen receptor stainingwas negative; however, further study must be undertaken.  相似文献   
78.
BACKGROUND: It is not clear that hepatic venous backflow actually contributes to hepatic tissue oxygenation under inflow occlusion of the liver. In order to prove that substances delivered via the hepatic vein can be utilized and/or metabolized in hepatocytes during inflow occlusion, hepatic uptake in bile and excretion of indocyanine green (ICG) were investigated in pigs. MATERIALS AND METHODS: Animals were divided into two groups: an inflow occlusion (IO) group (N = 6) and a total hepatic vascular exclusion (THVE) group (N = 3) using a bypass. One milligram of ICG per kilogram body weight was administered at the beginning of blood flow occlusion, the retention rate in the blood (ICG R) measured, and the ICG in the hepatic tissue measured by near-infrared (NIR) spectroscopy. Furthermore, the ICG concentration was measured in bile excreted by intermittent perfusion of the liver. RESULTS: ICG R declined with time in both groups; however, ICG R in the IO group decreased much faster than in the THVE group. There were significant differences between the two groups after 30 min of occlusion (P < 0.05). ICG in the hepatic tissue could be detected as a peak at 805 nm 10 min after ICG injection, and the peak became steeper with time. On the other hand, ICG was not detected at all in the hepatic tissue after 180 min in the THVE group. ICG was excreted in the bile after 60 min under IO and increased with time. On the contrary, ICG was not excreted in the bile at all under THVE. There were significant differences between the two groups after 90 min (P < 0.05). CONCLUSION: These results indicate that ICG can be extracted in hepatocytes and excreted in bile under IO of the liver. Consequently, substances such as oxygen and drugs, which are delivered via the hepatic vein, can be utilized and/or metabolized in hepatocytes under IO.  相似文献   
79.
Iwashita T  Tanaka Y  Hongo K  Koyama Ji J  Koyama T  Nitta J 《Neurosurgery》2002,50(4):881-4; discussion 884
OBJECTIVE AND IMPORTANCE: A rare case of an aneurysm arising at the fenestration of the P2 segment of the posterior cerebral artery is reported. CLINICAL PRESENTATION: A 37-year-old man presented with severe headache and disturbance of consciousness. Computed tomographic scanning showed diffuse subarachnoid hemorrhage. Cerebral angiography revealed an aneurysm at the fenestration of the P2 segment of the right posterior cerebral artery. The aneurysm was located at the middle portion of the lower trunk of the fenestration. An unruptured arteriovenous malformation was incidentally found in the right thalamus. INTERVENTION: A right frontotemporal craniotomy with orbitozygomatic osteotomy was made, and the aneurysm was successfully clipped. One year after the operation, gamma knife surgery was performed for the right thalamic arteriovenous malformation. CONCLUSION: This is the first reported case of an aneurysm originating from the middle portion of a fenestrated posterior cerebral artery.  相似文献   
80.
Since 1973, we have identified 4 cardiac tumors by ultrasonography in fetal or early postnatal life. Tuberous sclerosis was diagnosed in three infants whose mother was also affected. The first infant died from acute cardiac failure after birth, and the second required cardiac surgery. The third infant had a cardiac tumor and a focal seizure at the age of 8 months. The cardiac tumor disappeared at the age of 2 years. The fourth cardiac rhabdomyoma may be the only sign of tuberous sclerosis.  相似文献   
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