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991.
A histological evaluation of the involvement of Bio-Oss in osteoblastic differentiation and matrix synthesis 总被引:6,自引:0,他引:6
This study was designed to investigate the responses of bone cells to a deproteinized bovine bone material, Bio-Oss (Geistlich-Pharma, Wolhunsen, Switzerland), which was grafted in artificial bone defects of rat femurs. Standardized bone defects in the cortical bone of the right femurs were grafted with Bio-Oss particles. Narrow penetrations were prepared on the bottom of the cavity, enabling osteogenic cells to migrate from the bone marrow. A defect in the left femur without Bio-Oss was used as a control. The treated femurs were histochemically examined at 1, 3, 5, 7, and 14 days after the operation. At day 1, no osteogenic migration into the cavities occurred in either the control or experimental groups. At day 3, alkaline phosphatase (ALPase) immunohistochemistry showed a migration of the positive cells at the bottom of the cavities of the experimental groups, but not in the control ones. At day 5, new bone formation was recognized at the bottom of the cavity of both groups. In the experimental group, ALPase-positive cells were localized on Bio-Oss and/or on the thin bone matrix that covered this material. The superficial layer of Bio-Oss underlying the newly formed bone exhibited osteocalcin immunoreactivity. Transmission electron microscopy revealed osteoblasts depositing bone matrices--including collagen fibers--on the surface of Bio-Oss. At days 7 and 14, woven bone occupied the previous cavities of both control and experimental groups, accompanied by osteoclasts. Thus, Bio-Oss appears to serve as a scaffold for osteogenic cells as well as to promote osteoblastic differentiation and matrix synthesis. 相似文献
992.
Okano Y Hase Y Kawajiri M Nishi Y Inui K Sakai N Tanaka Y Takatori K Kajiwara M Yamano T 《Pediatric research》2004,56(5):714-719
Tetrahydrobiopterin (BH4)-responsive phenylalanine hydroxylase (PAH) deficiency is characterized by reduction of blood phenylalanine level after a BH4-loading test. Most cases of BH4-responsive PAH deficiency include mild phenylketonuria (PKU) or mild hyperphenylalaninemia (HPA), but not all patients with mild PKU respond to BH4. We performed the phenylalanine breath test as reliable method to determine the BH4 responsiveness. Phenylalanine breath test quantitatively measures the conversion of L-[1-13C] phenylalanine to 13CO2 and is a noninvasive and rapid test. Twenty Japanese patients with HPA were examined with a dose of 10 mg/kg of 13C-phenylalanine with or without a dose of 10 mg . kg(-1) . d(-1) of BH4 for 3 d. The phenylalanine breath test [cumulative recovery rate (CRR)] could distinguish control subjects (15.4 +/- 1.5%); heterozygotes (10.3 +/- 1.0%); and mild HPA (2.74%), mild PKU (1.13 +/- 0.14%), and classical PKU patients (0.29 +/- 0.14%). The genotypes in mild PKU cases were compound heterozygotes with mild (L52S, R241C, R408Q) and severe mutations, whereas a mild HPA case was homozygote of R241C. CRR correlated inversely with pretreatment phenylalanine levels, indicating the gene dosage effects on PKU. BH4 loading increased CRR from 1.13 +/- 0.14 to 2.95 +/- 1.14% (2.6-fold) in mild PKU and from 2.74 to 7.22% (2.6-fold) in mild HPA. A CRR of 5 to 6% reflected maintenance of appropriate serum phenylalanine level. The phenylalanine breath test is useful for the diagnosis of BH4-responsive PAH deficiency and determination of the optimal dosage of BH4 without increasing blood phenylalanine level. 相似文献
993.
High expression of PKC-MAPK pathway mRNAs correlates with glomerular lesions in human diabetic nephropathy 总被引:8,自引:0,他引:8
Toyoda M Suzuki D Honma M Uehara G Sakai T Umezono T Sakai H 《Kidney international》2004,66(3):1107-1114
BACKGROUND: Activation of protein kinase C (PKC) is a major signaling pathway for transforming growth factor (TGF)-beta to induce extracellular matrix (ECM) production in diabetic nephropathy (DN). PKC also activates mitogen-activated protein kinase (MAPK), which is called the PKC-MAPK pathway. The PKC-MAPK pathway is probably responsible for PKC-related abnormalities in diabetic glomeruli. To confirm the involvement of this pathway, we determined the localization and expression of mRNAs in glomeruli by in situ hybridization method. METHODS: In the present study, we examined expression of PKCbeta1, MAPK/ERK kinase (MEK) 1, MEK2, extracellular signal-regulated protein kinase (ERK) 1, ERK2, and TGF-beta1 mRNAs using renal tissue samples from kidneys affected by DN (N= 21) and from normal human kidney (NHK; N= 6). We also performed an immunohistochemical study using anti-phosphorylated MEK1/2 (P-MEK) and ERK1/2 (P-ERK) antibodies. The glomerular severity of DN was classified into three groups according to mesangial expansion: D1 (N= 4), D2 (N= 13), and D3 (N= 4). We analyzed differences and correlations between variables. RESULTS: In the glomeruli, the number of cells that stained for these mRNAs in DN was significantly higher than in NHK. The expression of PKC-MAPK pathway mRNAs tended to be inversely proportional to the degree of mesangial expansion. The P-MEK and P-ERK signal intensity were parallel to its mRNA expression pattern. Furthermore, there were significant correlations among the P-MEK, P-ERK signal intensity, PKCbeta1 mRNA expression. CONCLUSION: Our results suggest that high expression of PKC-MAPK pathway mRNAs plays an important role in the development and/or progression of early tissue damage in DN. 相似文献
994.
Yokoyama H Wada T Hara A Yamahana J Nakaya I Kobayashi M Kitagawa K Kokubo S Iwata Y Yoshimoto K Shimizu K Sakai N Furuichi K;Kanazawa Study Group for Renal Diseases Hypertension 《Kidney international》2004,66(6):2382-2388
BACKGROUND: A considerable diversity in prognosis is seen with lupus glomerulonephritis (LGN). Hence, the clinical usefulness of a recent International Society of Nephrology/Renal Pathology Society (ISN/RPS) 2003 classification to judge the long-term outcome of human LGN has been investigated. METHODS: We studied retrospectively 60 subjects with LGN (7 males, 53 females, mean age of 33 years old) who underwent renal biopsies and were followed from 1 to 366 months, with a mean of 187 months. We diagnosed renal pathology as classes, active and sclerosing lesions, according to the new and WHO1995 classification of LGN, and analyzed the clinicopathologic factors affecting to the prognosis of LGN. RESULTS: New classification got much higher consensus in the judgment of classes (98% vs. 83%, P = 0.0084). The group of Class IV-S (N = 6) or IV-G (N = 17) at initial biopsies showed higher rate of end-stage renal failure (ESRF) compared with that of Class I, II, III or V (40.9% vs. 2.6%, P < 0.001). The mean 50% renal survival time of Class IV was 189 +/- 29 months, and patients with Class IV-S tended to have a poorer prognosis (95 +/- 22 months for IV-S vs. 214 +/- 35 months for IV-G, P = 0.1495). Class IV was also selected as the most significant risk factor for ESRF by stepwise model (P = 0.002). In subanalysis for ESRF in Class IV (-S or -G), treatment including methylprednisolone pulse therapy was only selected as a significant improving factor for primary outcome (P = 0.034). In addition, activity index was the significant risk factor of death and/or ESRF after initial renal biopsies (P = 0.043). As for actuarial patient death during all follow-up periods, complications with anti-phospholipid syndrome or nephrotic syndrome were significant risk factors (P = 0.013, P = 0.041, respectively). CONCLUSION: New ISN/RPS 2003 classification provided beneficial pathologic information relevant to the long-term renal outcome and the optimal therapy preventing ESRF and/or death in patients with LGN. 相似文献
995.
Niwa M Kawakami H Nagaoka S Kanamori T Morisaku K Shinbo T Matsuda T Sakai K Kubota S 《Artificial organs》2004,28(5):487-495
We have developed a membrane oxygenator using a novel asymmetric polyimide hollow fiber. The hollow fibers are prepared using a dry/wet phase-inversion process. The gas transfer rates of O(2) and CO(2) through the hollow fibers are investigated in gas-gas and gas-liquid systems. The polyimide hollow fiber has an asymmetric structure characterized by the presence of macrovoids, and the outer diameter of the hollow fiber is 330 microm. It is found that the polyimide hollow-fiber oxygenator can enhance the gas transfer rates of O(2) and CO(2), and that the hollow fiber provides excellent blood compatibility in vitro and in vivo. 相似文献
996.
BACKGROUND AND OBJECTIVE: To investigate and compare the performance of bispectral index (BIS) and auditory evoked response index (AAI) in detecting the transition from consciousness to unconsciousness during anaesthesia induction by propofol, alone and in combination with fentanyl. METHODS: Anaesthesia was induced with either an intravenous infusion of 30 mg kg(-1)h(-1) of propofol plus 2 microg kg(-1) of fentanyl (Group PF, n = 20) or an intravenous infusion of 30 mg kg(-1) h(-1) of propofol plus normal saline (Group P, n = 20). BIS, AAI and the doses of propofol administered were recorded at the end-point of unresponsiveness to verbal commands. The propofol plasma concentration was also measured. RESULTS: The propofol dose and plasma propofol concentration required to achieve loss of consciousness were significantly lower in patients pretreated with fentanyl (P < 0.001). The mean BIS value at loss of consciousness was significantly different between the two groups (74.10 in Group PF vs. 60.80 in Group P) (P < 0.001). However, no difference in the AAI was seen between the two groups at loss of consciousness (32.90 in Group PF vs. 31.80 in Group P) (P > 0.05). In both groups, the regression analysis values (r-values) between BIS and plasma propofol concentrations at the onset of unconsciousness were higher than those between AAI and propofol concentrations (0.553 vs. 0.180 in Group P; 0.432 vs. 0.308 in Group PF). CONCLUSIONS: These results show that a fentanyl bolus is effective in augmenting the hypnotic effect of propofol during anaesthesia induction. AAI appears to be able to measure the transition from consciousness to unconsciousness at similar values, regardless of whether or not fentanyl pretreatment is used whereas the BIS values were not independent of fentanyl pretreatment. This suggests that AAI may be a better indicator of conscious status during propofol/fentanyl anaesthesia, where it appears to be independent of the anaesthesia regimen. 相似文献
997.
998.
999.
Suzuki Y Fujino Y Tanioka Y Sakai T Ajiki T Ueda T Tominaga M Kuroda Y 《World journal of surgery》2004,28(10):1007-1010
Simultaneous resection of the colon with pancreaticoduodenectomy (PD) is occasionally inevitable to accomplish curative resection in instances when a periampullary tumor involves the mesentery of the colon. However, there is little information regarding short- and long-term outcomes of this aggressive surgery. Among 95 consecutive patients who underwent PD for periampullary malignant tumors, 12 had simultaneous resection of the right colon (group 1) and 83 underwent PD alone (group 2). Intraoperative variables, postoperative morbidity and mortality, and the length of the hospital stay were comparatively analyzed. Survival was also compared between the groups in a subset of 36 pancreatic adenocarcinoma patients. Group 1 included more patients with pancreatic cancer, and portal vein resection was more frequently performed, which seemed to be associated with a significantly longer operating time (640 vs. 510 minutes) and increased total blood loss (1965 vs. 1220 ml). However, morbidity and mortality rates did not differ between the groups (50,0% and 0%, respectively, in group 1; 44.6% and 1.2%, respectively, in group 2). The median hospital stays were 67 and 48 days in groups 1 and 2, respectively. In a subset of 36 pancreatic adenocarcinoma patients, the median progression-free survivals were 6 months in both groups 1 and 2; the median overall survivals were 14 months in group 1 and 12 months in group 2. There was no statistically significant difference in survival between the groups. Simultaneous right hemicolectomy with curative intent at the time of PD could thus be performed safely and may offer a survival benefit even for individuals who have advanced pancreatic cancers with involvement of the transverse mesocolon. 相似文献
1000.
Dual Balloon-Occluded Retrograde Transvenous Obliteration of Gastric Varix Draining into the Left Adrenal Vein and Left Inferior Phrenic Vein 总被引:2,自引:0,他引:2
Nishida N Ninoi T Kitayama T Yamamoto A Sakai Y Sato K Hamuro M Nakamura K Inoue Y Yamada R 《Cardiovascular and interventional radiology》2004,27(5):560-562
A 66-year-old woman with a gastric varix, draining into a dilated left adrenal vein and a left inferior phrenic vein, was treated with dual balloon-occluded retrograde transvenous obliteration (B-RTO). Under balloon occlusion of the left adrenal vein and the left inferior phrenic vein, retrograde injection of a sclerosant (5% ethanolamine oleate) into the gastric varix was performed. Two weeks later, disappearance of flow in the gastric varix was confirmed on endoscopic ultrasound examination. 相似文献