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61.
62.
Tape-guided living donor left hepatectomy 总被引:5,自引:0,他引:5
Takatsuki M Kawashita Y Eguchi S Tajima Y Kanematsu T 《American journal of surgery》2007,194(1):107-109
A procedure of tape-guided living donor left hepatectomy is described. A tape was placed along the anterior wall of the inferior vena cava for left liver with caudate lobe, and along Arantius' ligament for left liver without caudate lobe. The final step of liver transection was applied by dividing the liver parenchyma under tape guidance. This procedure contributed to safe and accurate anatomic procurement of left liver grafts in living donor hepatectomy. 相似文献
63.
OBJECTIVES: Vascular endothelial growth factor (VEGF) is considered to play critical roles in tumor development and progression, especially in renal cell carcinoma (RCC) via von Hippel-Lindau gene inactivation. Although VEGF -2578CC, -1154GG, and -634CC genotypes are reportedly correlated with higher levels of VEGF production, no previous studies have reported on the associations of these polymorphisms with RCCs. This study was aimed to clarify the effects of these functional polymorphisms on RCC progression and prognosis. METHODS: We investigated the associations of three polymorphisms (-2578C/A, -1154G/A, and -634C/G) in the VEGF gene with the clinicopathologic parameters and survival of 213 patients with RCC. The -2578C/A and -634C/G polymorphisms were genotyped using a polymerase chain reaction (PCR) restriction fragment length polymorphism technique and the -1154G/A polymorphism was genotyped by an amplification refractory mutation system PCR technique. RESULTS: The GA+AA genotypes of -1154G/A were weakly associated with smaller tumors, lower tumor stage, and lower stage grouping (p=0.028, p=0.012, and p=0.028, respectively). The CA and CA+AA genotypes of -2578C/A were weakly associated with less frequent lymph node metastasis (p=0.029 and p=0.034, respectively) and were significantly associated with favorable cancer-specific survival (p=0.047 and p=0.048, respectively). There was no apparent clinical effect of the -634C/G polymorphism. CONCLUSIONS: These results suggest that some VEGF genotypes may have effects on RCC progression or prognosis, possibly through altered VEGF expression. This finding might help in clarifying the mechanisms of RCC development and progression. 相似文献
64.
Higashida T Sakata K Kanno H Tanabe Y Kawasaki T Yamamoto I 《No shinkei geka. Neurological surgery》2007,35(5):495-501
We reported two cases of intracranial skull base chondroma and discussed the differential diagnosis and the treatment strategies. The first case was a 39-year-old male who presented with left exophtalmos, visual loss and oculomotor disturbance. MRI showed a huge tumor occupying the bilateral cavernous sinus. Partial removal of the tumor was performed through the left orbitozygomatic subtemporal approach. The second case was a 54-year-old male who presented with left hemiparesis. MRI showed a brain stem infarction with a huge tumor located at the right middle fossa. Partial removal was performed through the right orbitozygomatic subtemporal approach. In these two cases, the histopathological diagnosis of the tumors was benign chondroma and the size of residual tumors have not changed for one year without any additional therapy. Although preoperative definite diagnosis for skull base chondromas is difficult, strategies for diagnosis and treatment without any complication are essential. In our cases, chondromas showed low uptake in PET images, which might be useful for differentiation between chondromas and chordomas. The current popular surgical approach for parasellar tumors is transcranial such as the orbitozygomatic subtemporal approach. In surgical removal of skull base chondromas, it is advisable to try to confirm the diagnosis preoperatively with characteristic image findings and to consider the best approach in each case to decompress the involved nerves without any complications. 相似文献
65.
Higashida T Kawasaki T Sakata K Tanabe Y Kanno H Yamamoto I 《Neurologia medico-chirurgica》2007,47(8):375-378
A 27-year-old man presented with a very rare spinal epidural mass associated with recurrence of acute lymphocytic leukemia (ALL) manifesting as acute progressive neurological deficits. The patient presented with shoulder pain and ambulatory difficulties 3 years after remission of ALL treated by bone marrow transplantation. Magnetic resonance imaging revealed an epidural mass extending from C-7 to T-3, which compressed the cord and extended to the intervertebral foramen along the roots. After decompression surgery, the symptoms dramatically improved. Histological examination showed clusters of immature lymphocytes consistent with recurrence of leukemia, so chemotherapy and radiation therapy were carried out. At 1 year after the operation, no local mass expansion or systemic progression of leukemia had occurred. Leukemic mass must be considered in the differential diagnosis of spinal epidural mass, even in patients with ALL. 相似文献
66.
BACKGROUND: Vasospasm is a frequent complication in the early clinical course after SAH. Although various methods have been used to measure cerebral perfusion including PET, SPECT, xenon CT, and TCD, these require the patients to remain still for a long period. In addition, TCD is operator dependent. The current study aimed to clarify the convenience of CTP for the assessment of cerebral vasospasm caused by SAH. METHODS: Nineteen patients with SAH aged 44 to 85 years (mean, 64 years) were recruited with informed consent. All patients were treated with the prevailing therapy and underwent CTP on days 6 to 9, followed by DSA and 3D-CTA to detect cerebral vasospasm. In each patient, we measured the MTT, CBF, and CBV. The reliability of CTP data was verified by comparing the data from CTP and xenon CT between the controls, and the average was calculated. Six ROIs were located symmetrically in the frontal, temporal, and occipital lobes. RESULTS: An MTT value more than 20% greater than the average indicated the progression of cerebral vasospasm, and patients with vasospasm-related infarcts exhibited an MTT more than 47% greater than the mean value (odds ratio, 50). Patients with delayed cerebral infarcts had a significantly lower mean CBF and CBV and higher MTT than patients who did not develop CI. CONCLUSION: Significant correlations between MTT and CBF values and neurovascular findings were obtained. Computed tomography perfusion can be performed in a short time and on a regular basis, and it therefore has the potential to identify cerebral vasospasm because of SAH. 相似文献
67.
Tomomi Toyoda Shinya Tosaka Reiko Tosaka Takuji Maekawa Sungsam Cho Susumu Eguchi Masahiro Nakashima Koji Sumikawa 《The Journal of surgical research》2014
Background
Ischemic postconditioning (PostC) protects the liver against ischemia-reperfusion (IR) injury. Milrinone, a phosphodiesterase 3 inhibitor, has been reported to exhibit preconditioning properties against hepatic IR injury; however, its PostC properties remain unknown. This study investigated whether milrinone has PostC properties against hepatic IR injury and the roles of phosphatidylinositol 3-kinase (PI3K) and nitric oxide synthase (NOS).Materials and methods
Male Wistar rats were separated into six groups: (1) group S: animals that underwent sham operation without ischemia, (2) group C: ischemia followed by reperfusion with no other intervention, (3) group M: milrinone administered immediately after reperfusion, (4) group MW: wortmannin, a PI3K inhibitor, injected before milrinone administration, (5) group MN: l-NAME, a NOS inhibitor, injected before milrinone administration, and (6) group MD, milrinone administered 30 min after reperfusion. Except for group S, all groups underwent 1 h of warm ischemia of median and left lateral lobes, followed by 5 h of reperfusion. Biochemical liver function analysis and histologic examination were performed.Results
Serum aspartate aminotransferase, alanine aminotransferase, and lactic dehydrogenase levels, histologic damage scores, and apoptotic rate in group M were significantly lower than those in group C. The inhibition of PI3K or NOS prevented this protective effect. Milrinone administered 30 min after reperfusion did not show obvious protective effects.Conclusions
Milrinone-induced PostC protects against hepatic IR injury when it is administered immediately after reperfusion, and PI3K and NOS may play an important role in this protective effect. 相似文献68.
Kengo Nomura Sawako Tatsumi Atsumi Miyagawa Yuji Shiozaki Shohei Sasaki Ichiro Kaneko Mikiko Ito Shinsuke Kido Hiroko Segawa Mitsue Sano Tsutomu Fukuwatari Katsumi Shibata Ken-ichi Miyamoto 《Journal of the American Society of Nephrology : JASN》2014,25(4):761-772
Marked hypophosphatemia is common after major hepatic resection, but the pathophysiologic mechanism remains unknown. We used a partial hepatectomy (PH) rat model to investigate the molecular basis of hypophosphatemia. PH rats exhibited hypophosphatemia and hyperphosphaturia. In renal and intestinal brush-border membrane vesicles isolated from PH rats, Na+-dependent phosphate (Pi) uptake decreased by 50%–60%. PH rats also exhibited significantly decreased levels of renal and intestinal Na+-dependent Pi transporter proteins (NaPi-IIa [NaPi-4], NaPi-IIb, and NaPi-IIc). Parathyroid hormone was elevated at 6 hours after PH. Hyperphosphaturia persisted, however, even after thyroparathyroidectomy in PH rats. Moreover, DNA microarray data revealed elevated levels of nicotinamide phosphoribosyltransferase (Nampt) mRNA in the kidney after PH, and Nampt protein levels and total NAD concentration increased significantly in the proximal tubules. PH rats also exhibited markedly increased levels of the Nampt substrate, urinary nicotinamide (NAM), and NAM catabolites. In vitro analyses using opossum kidney cells revealed that NAM alone did not affect endogenous NaPi-4 levels. However, in cells overexpressing Nampt, the addition of NAM led to a marked decrease in cell surface expression of NaPi-4 that was blocked by treatment with FK866, a specific Nampt inhibitor. Furthermore, FK866-treated mice showed elevated renal Pi reabsorption and hypophosphaturia. These findings indicate that hepatectomy-induced hypophosphatemia is due to abnormal NAM metabolism, including Nampt activation in renal proximal tubular cells.Inorganic phosphate (Pi) absorption in the renal proximal tubules and small intestine is important for Pi homeostasis.1 The Na+-dependent Pi (Na/Pi) transport system includes type IIa and type IIc Na/Pi transporters, which are localized in the apical membrane of the proximal tubular cells, and type IIb Na/Pi transporters, which are localized in the apical membrane of the intestinal epithelial cells.1,2 Pi (re)absorption is regulated by the dietary Pi content, parathyroid hormone (PTH), and the active metabolite of vitamin D, 1α, 25-dihydroxyvitamin D3 [1,25(OH)2D3].3 Other phosphaturic hormones, termed phosphatonins, also control renal Pi handling.4 The discovery that fibroblast growth factor (FGF) 23, the first identified phosphatonin,5 originated from osteocytes established the concept of the bone-kidney axis.6,7The incidence of liver transplantation has steadily increased and the incidence of partial hepatectomy (PH) has also consequently increased.8 Hypophosphatemia frequently occurs after liver resection.9–11 Acute hypophosphatemia causes septicemia and is associated with a poor prognosis.11,12 Acute hypophosphatemia is of considerable clinical relevance because many hepatectomized patients develop marked hypophosphatemia and, thus, large doses of Pi replacement are required to maintain metabolic homeostasis.13 Urinary Pi excretion is markedly increased in many patients. After hepatectomy, hypophosphatemia is associated with hyperphosphaturia.13For many years, the increased metabolic demand of the regenerating liver was considered the underlying pathologic mechanism of hypophosphatemia. The magnitude of Pi uptake by the recovering liver, however, cannot explain the severity of the resulting hypophosphatemia.11 Hepatectomy-induced hypophosphatemia is associated with an increased renal fractional excretion index for Pi unrelated to intact FGF23, FGF7, or secreted frizzled-related protein 4 as a phosphaturic factor,14 indicating that other factors have a role in the pathogenesis of hypophosphatemia.Nicotinamide (NAM) inhibits intestinal and renal Na/Pi transport activity in normal rats.15–17 Administration of NAM to rats produces a specific dose-dependent inhibition of Na/Pi transport across the renal brush-border membrane (BBM) and an increase in urinary Pi excretion.16,17 NAM suppresses hyperphosphatemia in hemodialysis patients.18 Nicotinamide phosphoribosyltransferase (Nampt) catalyzes the first rate-limiting step in converting NAM to NAD,19,20 which is essential for cellular metabolism, energy production, and DNA repair.20–22 Nampt exists in two known forms: intracellular Nampt (iNampt) and secreted extracellular Nampt (eNampt).23 eNampt also generates an intermediate product, nicotinamide mononucleotide (NMN).23Our findings indicate that the acceleration of NAM metabolism through Nampt function in the kidney is involved in the hepatectomy-induced hypophosphatemia in rodent models. This study also suggests that NAM metabolism through the liver-kidney axis is important in Pi homeostasis. 相似文献
69.
70.
Yoshinari Ogawa Katsumi Ikeda Kana Ogisawa Shinya Tokunaga Hiroko Fukushima Takeshi Inoue Yoshihiro Mori Akiko Tachimori Toru Inoue Yukio Nishiguchi 《Surgery today》2014,44(9):1633-1637