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991.
OBJECTIVES: The aim of this study is to evaluate the usefulness of gastroesophageal reflux (GER) scintigraphy using the knee-chest (KC) position for the diagnosis of gastroesophageal reflux disease (GERD). METHODS: The study subjects were 37 patients with GERD and 8 healthy volunteers (control group). Endoscopically observed esophageal mucosal breaks were evaluated with the Los Angeles classification. For GER scintigraphy, the subjects ingested liquid yogurt labeled with 99mTc-diethylene triamine pentaacetic acid (99mTc-DTPA) and water. Imaging was performed in the supine and KC position, and GER was graded as 1-4 according to the extent of GER assessed by scintigraphy. RESULTS: GER scintigraphy revealed no reflux in the control group (specificity: 100%). In the supine position, gastroesophageal reflux was observed in 49% of the patients with GERD, compared to 76% in the KC position. 21 of 23 (91%) patients with erosive esophagitis were shown to have GER with scintigraphy. GER scintigraphy revealed severe reflux (grade 3 or 4) (83%, 10/12) in the patients who had severe mucosal breaks (LA grade C or D). GER scintigraphy detected grade 1 or 2 reflux in 7 of the 14 patients who were endoscopically negative. There was a correlation between the endoscopically determined severity of mucosa and the reflux grade which was determined with GER scintigraphy. CONCLUSION: GER scintigraphy can detect gastroesophageal reflux with a high sensitivity in the KC position and might be a useful method in the screening and assessment of the severity of this disease. This method would be useful for the diagnosis of GERD in endoscopically negative patients. 相似文献
992.
Holton AD Walsh EG Brott BC Venugopalan R Hershey B Ito Y Shih A Koomullil R Anayiotos AS 《Journal of magnetic resonance imaging : JMRI》2005,22(2):248-257
PURPOSE: To evaluate different grades of in-stent stenosis in a nickel-titanium stent with MRI. MATERIALS AND METHODS: Magnetic resonance phase velocity mapping (MR-PVM) was used to measure flow velocity through a 9-mm NiTi stent with three different degrees of stenosis in a phantom study. The tested stenotic geometries were 1) axisymmetric 75%, 2) axisymmetric 90%, and 3) asymmetric 50%. The MR-PVM data were subsequently compared with the velocities from computational fluid dynamic (CFD) simulations of identical conditions. RESULTS: Good quantitative agreement in velocity distribution for the 50% and 75% stenoses was observed. The agreement was poor for the 90% stenosis, most likely due to turbulence and the high-velocity gradients found in the small luminal area relative to the pixel resolution in our imaging settings. CONCLUSION: The accuracy of the MRI velocities inside the stented area renders MRI a modality that may be used to assess moderate to severe in-stent restenosis (ISR) in medium-sized vascular stents in peripheral vessels, such as the iliac, carotid, and femoral arteries. Advances in MR instrumentation may provide sufficient resolution to obtain adequate velocity information from smaller vessels, such as the coronary arteries, and allow MRI to substitute for invasive and expensive catheterization procedures currently in clinical use. 相似文献
993.
Erk pathways negatively regulate matrix mineralization 总被引:1,自引:0,他引:1
Skeletal mineralization is an important step regulating the mechanical properties of the calcified tissues, but molecular events underlying mineralization still remain elusive. We examined the role of extracellular signal-regulated kinase (Erk) pathways in matrix mineralization of osteogenic cells both in vitro and in vivo. Matrix mineralization by preosteocytic MLO-A5 cells and osteoblastic MC3T3-E1 cells was increased by either PD98059 Mek inhibitor treatment or adenovirus vector-mediated dominant negative Ras (Ras(DN)) expression and was suppressed by Erk activation by platelet-derived growth factor (PDGF) treatment or constitutively active Mek1 (Mek(CA)) expression. Administration of adenovirus vectors carrying Ras(DN) gene onto the calvaria of 1-day-old mice increased the mineralization of the tissues, while that of the Mek(CA) adenovirus suppressed it. These results suggest that the Erk pathway is a negative regulator of the matrix mineralization both in vitro and in vivo. 相似文献
994.
Yoshio Suzuki Taisei Miyahara Minami Jinnouchi Yoshiki Miura Hikari Taka Naoko Kaga Akiko Ohara-Takada 《Nutrients》2022,14(9)
We previously reported that healthy adult males who consumed coix seeds for 1 week demonstrated an increased intestinal abundance of Faecalibacterium prausnitzii and altered peripheral lymphocyte subset percentages. However, the mechanism underlining these effects has not been elucidated. Therefore, cytokines and metabolites in plasma obtained in this study are comprehensively analyzed. A total of 56 cytokines and 52 metabolites in the plasma are quantified. Among them, 14 cytokines and 9 metabolites show significant changes in their levels following coix seed consumption. We examine the relationship between these changes and those in peripheral lymphocyte subset percentages and intestinal abundance of F. prausnitzii, which is also considerably altered following coix seed consumption. The galectin-9 concentration considerably decreased after coix seed consumption, and these changes correlate with those in cytotoxic T cells and pan T cells. Therefore, galectin-9 is possibly involved in the changes in peripheral lymphocyte subset percentages induced by coix seed consumption. 相似文献
995.
Nobuyuki Nishikawa Rie Yago Yuichiro Yamazaki Hiromitsu Negoro Mari Suzuki Masaaki Imamura Yoshinobu Toda Kazunari Tanabe Osamu Ogawa Akihiro Kanematsu 《BMC urology》2015,15(1)
Background
To investigate the expression of parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor 1 (PTH1R) in clinical specimens of normal and diseased bladders. PTHrP is a unique stretch-induced endogenous detrusor relaxant that functions via PTH1R. We hypothesized that suppression of this axis could be involved in the pathogenesis of bladder disease.Methods
PTH1R expression in clinical samples was examined by immunohistochemistry. Normal kidney tissue from a patient with renal cancer and bladder specimens from patients undergoing ureteral reimplantation for vesicoureteral reflux or partial cystectomy for urachal cyst were examined as normal control organs. These were compared with 13 diseased bladder specimens from patients undergoing bladder augmentation. The augmentation patients ranged from 8 to 31 years old (median 15 years), including 9 males and 4 females. Seven patients had spinal disorders, 3 had posterior urethral valves and 3 non-neurogenic neurogenic bladders (Hinman syndrome).Results
Renal tubules, detrusor muscle and blood vessels in normal control bladders stained positive for PTH1R. According to preoperative urodynamic studies of augmentation patients, the median percent bladder capacity compared with the age-standard was 43.6% (range 1.5–86.6%), median intravesical pressure at maximal capacity was 30 cmH2O (range 10–107 cmH2O), and median compliance was 3.93 ml/cmH2O (range 0.05–30.3 ml/cmH2O). Detrusor overactivity was observed in five cases (38.5%). All augmented bladders showed negative stainings in PTH1R expression in the detrusor tissue, but positive staining of blood vessels in majority of the cases.Conclusions
Downregulation of PTH1R may be involved in the pathogenesis of human end-stage bladder disease requiring augmentation. 相似文献996.
Horita K Matsunami H Shimizu Y Shimizu A Kurimoto M Suzuki K Tsukadaira T Arai M 《Transplantation》2002,73(12):1909-1912
BACKGROUND: Decompensated hepatitis C virus (HCV)-related cirrhosis is the main indication for liver transplantation. We report the first successful living-related liver transplantation in a 49-year-old hemophilia A patient with end-stage HCV-related cirrhosis using a graft obtained from his 20-year-old daughter, an obligate carrier. METHODS: The donor's autologous fresh-frozen plasma rich in factor VIII (FVIII) by treatment with 1-deamino-8-D-arginine vasopressin was prepared before the operation. At induction, 1-deamino-8-D-arginine vasopressin was given to the donor to increase plasma FVIII level. In addition, autologous fresh-frozen plasma containing high FVIII concentrate was infused intraoperatively. The right lobe was harvested from the donor and transplanted orthotopically. The recipient was treated postoperatively with recombinant FVIII and immunosuppressive agents. RESULTS: The donor did not receive recombinant FVIII or allogenic blood during perioperative periods. No bleeding was encountered in the donor perioperatively. The recipient showed a steady increase in FVIII activity postoperatively and was discharged 40 days after transplantation. Ribavirin and interferon-alpha were provided for 3 months postoperatively to prevent potential recurrence of HCV infection. Serum HCV-RNA by RT-PCR became negative after such treatment. CONCLUSIONS: End-stage liver disease in patients with hemophilia A can be an indication for living-related liver transplantation. Furthermore, a graft from a living-related donor with hemophilia A carrier seems to be suitable provided such individuals receive adequate support for coagulopathies. 相似文献
997.
Summary We report a rare case with tetralogy of Fallot (TOF) and agenesis of the internal carotid artery (ICA) who presented serious
intracerebral haematomas. In the literature, this is the first documented case having these complications simultaneously.
Extreme hypoxic insults followed by recovery were detected by O2 saturation monitor before two bleeds. Chronic brain hypoxia could make the vasculature weak, which was shown in the histological
examination.
A 2-year-old girl was transferred to us with a general convulsion due to intracerebral haematoma. She had been showing general
cyanosis from birth due to TOF. Repeated intracerebral haemorrhages ended her life. Histological study showed dilated vascular
channels in the subarachnoid space and necrotizing vasculature obstructed by fibrinous thrombi adjacent to the haematoma.
Fibrosis of the vessel wall with infiltration of macrophages suggested subacute or chronic lesions rather than acute necrosis
due to the multiple haemorrhages. The intracerebral haematomas and agenesis of the ICA were observed as unilateral hemispheric
vascular complications of TOF. Chronic brain hypoxia could play an important role in weakening the vessel wall and erythrocytosis
caused obstructing thrombi. We speculate these factors generated the intracerebral haematomas. 相似文献
998.
Hiroki Ochi Yasushi Hara Masahiro Tagawa Kenichi Shinomiya Yoshinari Asou 《Journal of orthopaedic research》2010,28(5):657-663
LPS (lipopolysaccharide), a major constituent of Gram‐negative bacteria, regulates proliferation and differentiation of osteoclasts directly or indirectly. This study sought to investigate the functions of the RANK/RANKL pathway in LPS‐induced bone loss in vivo. Wild‐type mice or TNFR1?/? mice were injected LPS with or without osteoprotegerin (OPG) and analyzed histologically. Bone volume was reduced by LPS injection in all groups, and OPG administration prevented the LPS‐induced bone loss regardless of genotypes. LPS‐induced enhancement of osteoclastogenesis in wild‐type mice was blocked by OPG administration. LPS or OPG did not affect osteoclastogenesis in TNFR1?/? mice. Interestingly, osteoblast surface was remarkably reduced in LPS‐treated TNFR1?/? mice as a result of enhanced osteoblast apoptosis. TRAIL, induced by TNF‐α in BMC, triggered apoptosis of primary osteoblast only when TNFR1 signal was ablated in vitro. In conclusion, RANK signaling plays a prominent role in osteoclastogenesis downstream of LPS. Furthermore, TNFR1 regulates bone metabolism through not only the regulation of osteoclast differentiation but also osteoblast survival. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:657–663, 2010 相似文献
999.
Keiichi Suzuki Osamu Itano Go Oshima Masayoshi Osaku Fumiki Asanuma Yuko Kitagawa 《World journal of surgery》2014,38(5):1205-1210
Background
Laparoscopic splenic vessel-preserving distal pancreatectomy (lap-SVPDP) is a popular procedure in pancreatic surgery. However, postoperative complications include false aneurysms of the splenic artery, splenic vein stenosis and thrombosis, pancreatic fistulas, abscess, and perigastric varices.Methods
Eight patients (three men, five women, average age 66.1 years) with benign tumors underwent lap-SVPDP. Lap-SVPDP was performed in the lithotomy position with the head slightly elevated. The splenic vein was peeled longitudinally toward the pancreatic tail. A vessel-sealing system was used to detach the pancreatic body from the greater omentum, and the pancreas was transected using a surgical stapler.Results
Mean operation time was 254 min; mean blood loss was 163 ml; and mean post-surgical hospitalization time was 13 days. No postoperative bleeding from the preserved splenic vessels occurred, and there were no splenic infarcts or splenic abscesses.Conclusions
For safe performance of lap-SVPDP, the posterior surface of the pancreas should be completely exposed. The splenic vein should be ‘peeled away’, starting from its central rear, enabling easy detection of its course to avoid inadvertent sealing. With improved operational techniques, lap-SVPDP can be adopted as a standard procedure in pancreatic surgery. 相似文献1000.
Takagawa R Fujii S Ohta M Nagano Y Kunisaki C Yamagishi S Osada S Ichikawa Y Shimada H 《Annals of surgical oncology》2008,15(12):3433-3439
Background We evaluated the prognostic value of the preoperative serum carcinoembryonic antigen (CEA) level in patients with colorectal
cancer (CRC).
Patients and Methods The study group comprised 638 patients. The optimal cutoff value for the preoperative serum CEA level was determined. Predictive
factors of recurrence were evaluated using multivariate analyses. The relapse-free time was investigated according to the
CEA level.
Results All patients underwent potentially curative resection for CRC without distant metastasis, classified as stage I, II, or III.
The optimal cutoff value for preoperative serum CEA level was 10 ng/ml. Elevated preoperative serum CEA level was observed
in 92 patients. Multivariate analysis identified tumor–node–metastasis (TNM) stage and preoperative serum CEA level as independent
predictive factors of recurrence. The relapse-free survival between CEA levels >10 ng/ml and <10 ng/ml significantly differed
in patients with stage II and III. However, there was no significant difference in relapse-free survival between CEA levels
>10 ng/ml and <10 ng/ml in patients with stage I.
Conclusion Preoperative serum CEA is a reliable predictive factor of recurrence after curative surgery in CRC patients and a useful indicator
of the optimal treatment after resection, particularly for cases classified as stage II or stage III. 相似文献