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91.

Background

Epidermal growth factor receptor (EGFR) signaling is one of the most promising targets for molecular-targeted therapies in esophageal squamous cell carcinoma (ESCC). Thus, the molecular diagnosis of KRAS and BRAF mutations is clinically important in therapeutic decision making. However, the frequency of KRAS and BRAF mutations in ESCCs remains inconclusive because of the limited sample sizes of previous studies (all N ≤ 80). Pyrosequencing is a nonelectrophoretic nucleotide extension sequencing technology that can be used for mutation testing.

Methods

The frequency of KRAS and BRAF mutations was examined using a nonbiased database of 203 resected ESCCs and a high-throughput pyrosequencing assay.

Results

The validity of the KRAS pyrosequencing method was initially demonstrated by detection of all 4 types of KRAS mutations [c.35G>T (codon 12 GGT>GTT), c.35G>A (codon 12 GGT>GAT), c.34G>T (codon 12 GGT>TGT), c.38G>A mutation (codon 13 GGC>GAC)], which had been previously diagnosed using Scorpion-ARMS technology, in 9 colon cancer tissues (9 of 9; 100 %). Similar results were demonstrated for BRAF mutational status in 3 colon cancer cell lines (HCT116, Colo201, and HT29), which were validated by Sanger dideoxy sequencing. Subsequently, the KRAS mutation was found to be extremely rare (1 of 203; 0.5 %), and the BRAF mutation was absent (0 of 203; 0 %), in the dataset of 203 ESCCs.

Conclusions

These results suggest that KRAS and BRAF mutations play a limited role in the development of ESCC and that mutation analysis is not useful as a screening test for sensitivity to anti-EGFR therapy in ESCC.
  相似文献   
92.
Oki H  Ando M  Omori H  Okumura Y  Negoro K  Uchida K  Baba H 《Artificial organs》2004,28(11):1050-1054
In acetabular dysplasia, more vertical orientation of the acetabular component is often used to minimize the superolateral bone grafting. This study was designed to determine the effects of vertical orientation of the cup on the stability and polyethylene wear of the acetabular component in uncemented total hip arthroplasty (THA). Three-dimensional finite element models of the hemipelvis with dysplastic acetabulum were developed. Metal-backed hemispherical cups were placed in the true acetabulum with abduction angles of 35, 45, 55, and 65 degrees. It was found that more vertical orientation of the cup was associated with larger relative motion of the metal shell between the acetabulum and metal shell. Furthermore, tilting and torsional shear stresses in the model of the cup abduction angle of 65 degrees were found to be 1.7 times larger than that in the model with 35 degrees at the bone-metal shell interface. More vertically oriented cups caused larger contact stresses at the articulating surfaces of the polyethylene liners. The results suggest that the abduction angle of the acetabular component significantly influences cup loosening and polyethylene wear in THA.  相似文献   
93.
It is assumed that hepatobiliary, cell-specific contrast agents will be adversely affected by the presence of diffuse liver disease. The diagnostic efficacy for tumor detection in the presence of fatty liver disease was experimentally studied at contrast-enhanced magnetic resonance (MR) imaging with manganese-DPDP (N,N′-dipyridoxylethylenediamine-N,N′-diacetate 5,5′-bis[phosphate]) and gadobenate dimeglumine (Gd-BOPTA/dimeg) and compared with conventional and chemical shift imaging. Carcinosarcoma was implanted into the liver of rats, and fatty liver was induced with L-ethionine. Without contrast agents, the tumor-fatty liver contrast-to-noise ratio (C/N) was increased on T1-weighted and decreased on T2-weighted MR images relative to tumor-bearing control rats without fatty liver. Chemical shift imaging (phase-contrast method) increased the tumor—fatty liver C/N from 2.3 ± 1.0 to 6.1 ± 1.7 (P <.001). Mn-DPDP and Gd-BOPTA/dimeg increased the tumor—fatty liver C/N from -5.4 ± 1.6 to -11.0 ± 1.9 and ?9.8 ± 3.4, respectively (P <.001). The hepatobiliary, cell-specific contrast agents were equally effective in both fatty and nonfatty liver and outperformed both chemical shift and conventional MR imaging in detecting liver tumors.  相似文献   
94.
Previously unreported effects of tissue storage were recently observed in the authors' experimental magnetic resonance (MR) studies. To evaluate the effect of elapsed time after excision and storage temperature on tissue relaxation time measurements, tissue samples from the liver, pancreas, kidney, testis, spleen, and brain were obtained in rats. T1 and T2 were first measured within 5 minutes of excision, and between subsequent measurements, tubes were kept in a water bath at 40°C, at room temperature (28°C), or in an ice bath (4°C). Cellular and organellar integrity was assessed with electron microscopy and correlated with the MR findings. At 40°C (20-MHz spectrometer), the T1 of liver decreased from 280 msec ± 8 to 212 msec ± 10 during the first 60 minutes; the T1 of pancreas decreased from 276 msec ± 3 to 208 msec ± 2. Other tissues showed less than a 5% decrease in T1. T2 changes were smaller than T1 changes in all tissues. Electron microscopy of pancreatic acinar cells showed postmortem changes in mitochondria evolving over the first 60 minutes after death. Manganese loading experiments implicated mitochondrial manganese stores in the observed enhanced postmortem decrease in T1. This study calls into question reported relaxation time data for liver and pancreas. MR studies of excised tissues must account for time and temperature to prevent systematic experimental errors.  相似文献   
95.
We studied the effects of the cyclooxygenase inhibitors, indomethacin and aspirin, the leukotriene antagonist, FPL 55712 and the Ca antagonist, verapamil on basal tone and Ca-induced contractions in the human and guinea-pig tracheal muscle. Indomethacin and aspirin usually increased spontaneous tone or Ca-induced contractions in human strips, while consistently decreased tension development in the guinea-pig muscle. FPL 55712 strongly reduced contractions in the human, whereas it had a very weak effect on the guinea-pig muscle. Verapamil had a small inhibitory effect in the human trachea, either at 5.9 or 40 mM K, but markedly suppressed Ca-induced contractions of guinea-pig trachea in 40 mM K and had little effect on contractions in 5.9 mM K in this tissue. It is concluded that active tone in the two different tracheal muscles were controlled by different processes; that different arachidonate by-products may exert an effect on basal tone in the two different muscles; and that different plasma membrane Ca channels may be operative under basal conditions in the different muscles.  相似文献   
96.
Immunotherapeutic intervention has been studied in non-obese diabetic (NOD) mice. Twenty-five male NOD mice aged 6 weeks were treated with anti-mouse T lymphocyte serum (ATS), N-(2-carboxyphenyl)-4-chloroanthranilic acid disodium salt (CCA); a non-specific immunostimulant which seems to potentiate the suppressor T cell activity, and antiserum raised against previously reported monoclonal antibody 3A4 to the surface of islet cells. Pancreatic islets from NOD mice sacrificed at 12 weeks of age were scored morphologically for the severity and the frequency of insulitis. Both the severity of insulitis in each islet and the frequency of insulitis-positive islets in each pancreas were reduced in the groups treated with ATS (group B), antiserum to 3A4 (group D) and a combination of antiserum plus CCA (group E) in comparison with other groups (control: group A and CCA: group C). At 8 weeks of age, the binding capacities of sera to insulinoma cells measured by protein A radioligand assay were significantly decreased in the groups treated with antiserum to 3A4 (groups D and E) as compared with those in the other groups. These results suggest that both ATS and antiserum to 3A4 prevent the occurrence and the progress of insulitis in NOD mice, but the immunosuppressive mechanisms differ from each other; therefore, combination therapy with these suppressants may be more effective in the prevention of Type 1 diabetes mellitus.  相似文献   
97.
Transmesenteric hernia is a rare cause of bowel obstruction in adults. We herein describe two cases that occurred in adult women, ages 27 and 19. Both cases presented with abdominal pain without muscular defense signs. Computed tomography of both cases showed features of small bowel obstruction by an internal hernia. A laparotomy showed mesenteric defects of the mesentery of the ileum in the former case and the mesentery of the transverse colon in the latter case, with a herniating ileum. The involved small bowel was viable in both cases, and the bowel was pulled out of the mesenteric defect without resection. The mesenteric defects were then successfully repaired.  相似文献   
98.

Purpose

Elderly patients with multiple infarctions revealed a high prevalence of postoperative stroke after coronary artery bypass grafting (CABG). However, postoperative neurological complications and characteristics of silent brain infarction (SBI) have not been evaluated in elderly patients undergoing CABG.

Methods

Four hundred forty-nine patients (??60 years old) scheduled for CABG underwent cerebral magnetic resonance imaging (MRI) and MR angiography preoperatively to assess cerebral infarctions and carotid and intracranial artery stenosis. Atherosclerosis of the ascending aorta was assessed by epiaortic ultrasound during surgery. Patients were sorted by their history of cerebrovascular disease (CVD) and the presence of infarction by MRI: SBI (infarction without CVD), BI (symptomatic brain infarction; CVD and infarction), and controls (no findings of either CVD or infarction).

Results

SBI was found in 35.5% of the 449 patients and increased with age. The prevalence of pre-existing multiple infarctions was less frequent in SBI than in BI. The incidence of postoperative stroke and cognitive dysfunction was 1.3% and 4.9% in controls (n?=?225), 5.7% and 15.2% in SBI (n?=?158), and 9.1% and 18.2% in BI (n?=?66). Patients with SBI were older and had more renal dysfunction and preoperative cognitive impairment. Stepwise logistic regression demonstrated that age, renal dysfunction, preoperative cognitive impairment, atherosclerosis of the ascending aorta, and intracranial arterial stenosis were associated significantly with SBI.

Conclusion

Patients with SBI were ranked at moderate risk of neurological complications after CABG between control and BI. Increased age, renal dysfunction, and preoperative cognitive impairment appeared to be strongly associated with SBI.  相似文献   
99.
Esophageal cancer frequently occurs in the elderly and many of the patients have smoking history. Therefore, some of them have pulmonary comorbidity such as chronic respiratory diseases. As postoperative pulmonary complications after esophagectomy can be a cause of hospital death, careful evaluation is needed before the decision of the indication for surgery. In order to prevent postoperative pulmonary complications in patients with pulmonary comorbidities, modifications in the surgical procedures are needed. Even for cases who can tolerate standard esophagectomy, both the bronchial arteries and pulmonary branches of the vagal nerve should be preserved as far as possible. For patients who cannot tolerate the thoracotomy, transhiatal esophagectomy or non-surgical treatment should be selected. Postoperatively, airway cleansing using a bronchoscopy or mini-tracheostomy should be performed for cases with difficulty in sputum excretion. An enhanced recovery program by multidisciplinary team is effective to prevent postoperative pulmonary complications. Perioperative use of corticosteroid and sivelestat may reduce the incidence of pulmonary complications. As aspiration pneumonia is sometimes fatal in patients after esophagectomy, care to avoid aspiration is needed. Respiratory care is essential during the follow-up period as well as perioperative period in esophagectomized patients with pulmonary comorbidities.  相似文献   
100.
Situs inversus totalis is a rare congenital anomaly in which the major abdominal organs are located as a mirror image of their normal positions. This poses much difficulty for surgeons. We describe how we performed the liver-hanging maneuver (LHM) for hepatocellular carcinoma (HCC) in a 59-year-old man with situs inversus totalis, to resolve the difficulty of the mirror-image location of his liver. The HCC was located in the right lateral sector. Although segmentectomy of segment 7 would normally be considered minimal for a curative treatment of HCC, this was relatively complicated in this patient. Thus, we performed an extended right lateral sectionectomy using the LHM to achieve a simple transection. The hepatic hilum was dissected using the Glissonean pedicle transection method. The operation time and intraoperative blood loss were 6 h 45 min and 471 ml, respectively. No blood product transfusion was required. The LHM and the hilar Glissonean pedicle approach proved effective for resolving the difficulties of performing surgery in a mirror image for HCC in a patient with situs inversus totalis.  相似文献   
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