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1.
BACKGROUND AND STUDY AIMS: As endoscopic techniques continue to develop, endoscopic mucosal resection is increasingly being used in the treatment of intramucosal gastric tumors. The aim of this study was to explore the feasibility of piecemeal endoscopic aspiration mucosectomy for large superficial intramucosal tumors of the stomach. PATIENTS AND METHODS: The study group consisted of five consecutive patients with large superficial intramucosal tumors of the stomach, 4 cm or more in diameter. Piecemeal endoscopic aspiration mucosectomy using a cap-fitted panendoscope was carried out. The initial resection was undertaken at the oral side of the lesion. Subsequent resections were carried out along the anal margin of the previous resection site, until the marks around the boundary of the tumor completely disappeared. RESULTS: The shape of the tumors was slightly elevated in four cases and slightly depressed in one. The mean diameter of the tumors was 4.8 cm. The diameters of the resected specimens ranged from approximately 1.0 cm to 2.3 cm. The numbers of piecemeal resection procedures needed per lesion ranged from five to 18 (mean 11). The visual field was well ensured by the cap, and the tumors were macroscopically completely resected without any complications in all patients. The final histological diagnoses in the specimens were adenoma in one case and mucosal carcinoma in adenoma in four. One patient had residual or recurrent tumor, and received full treatment with additional endoscopic procedures. CONCLUSIONS: Piecemeal endoscopic aspiration mucosectomy is a simple and very useful technique for treating large superficial intramucosal tumors of the stomach.  相似文献   
2.
FMS‐like tyrosine kinase 3 (FLT3) plays a key role in hematopoiesis. However, the oncogenic role of FLT3 amplification in patients with metastatic colorectal cancer (mCRC) remains unclear. Here, we aimed to evaluate the characteristics, prognosis, and treatment efficacy of an FLT3 inhibitor (regorafenib) in patients with mCRC with FLT3 amplifications. Tumor tissue samples from 2329 patients were sequenced using NGS in the Nationwide Cancer Genome Screening Project in Japan. The effects of clinicopathological features, co‐altered genes, prognosis, and efficacy of regorafenib were investigated. Between April 2015 and June 2018, 85 patients with mCRC with FLT3 amplification were observed. There were no differences in baseline characteristics between patients with or without FLT3 amplification. The frequency of RAS or other gene co‐alterations was inversely correlated with the copy number status. Median survival time in patients with FLT3 amplification was significantly shorter compared with those with non‐FLT3 amplification. Further investigations of FLT3 amplification as a potential treatment target in mCRC are warranted.  相似文献   
3.
This study aimed to clarify the clinical characteristics and oncological outcomes of patients with upper tract urothelial carcinoma (UTUC) who developed muscle-invasive bladder cancer (MIBC) after radical nephroureterectomy (RNU). We identified 966 pTa-4N0-2M0 patients with UTUC who underwent RNU and clarified the risk factors for MIBC progression after initial intravesical recurrence (IVR). We also identified 318 patients with primary pT2-4N0-2M0 MIBC to compare the oncological outcomes with those of patients with UTUC who developed or progressed to MIBC. Furthermore, immunohistochemical examination of p53 and FGFR3 expression in tumor specimens was performed to compare UTUC of MIBC origin with primary MIBC. In total, 392 (40.6%) patients developed IVR after RNU and 46 (4.8%) developed MIBC at initial IVR or thereafter. As a result, pT1 stage on the initial IVR specimen, concomitant carcinoma in situ on the initial IVR specimen, and no intravesical adjuvant therapy after IVR were independent factors for MIBC progression. After propensity score matching adjustment, primary UTUC was a favorable indicator for cancer-specific death compared with primary MIBC. Subgroup molecular analysis revealed high FGFR3 expression in non-MIBC and MIBC specimens from primary UTUC, whereas low FGFR3 but high p53 expression was observed in specimens from primary MIBC tissue. In conclusion, our study demonstrated that patients with UTUC who develop MIBC recurrence after RNU exhibited the clinical characteristics of subsequent IVR more than those of primary UTUC. Of note, MIBC subsequent to UTUC may have favorable outcomes, probably due to the different molecular biological background compared with primary MIBC.  相似文献   
4.
Acute myeloid leukemia (AML) is hierarchically organized by self-renewing leukemic stem cells (LSCs). LSCs originate from hematopoietic stem cells (HSCs) by acquiring multistep leukemogenic events. To specifically eradicate LSCs, while keeping normal HSCs intact, the discrimination of LSCs from HSCs is important. We have identified T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) as an LSC-specific surface molecule in human myeloid malignancies and demonstrated its essential function in maintaining the self-renewal ability of LSCs. TIM-3 has been intensively investigated as a “coinhibitory” or “immune checkpoint” molecule of T cells. However, little is known about its distinct function in T cells and myeloid malignancies. In this review, we discuss the structure of TIM-3 and its function in normal blood cells and LSCs, emphasizing the specific signaling pathways involved, as well as the therapeutic applications of TIM-3 molecules in human myeloid malignancies.  相似文献   
5.
International Journal of Clinical Oncology - We here applied cancer personalized profiling by deep sequencing (CAPP-seq) to analysis of circulating tumor DNA (ctDNA) to identify resistance...  相似文献   
6.
Miloxacin, a synthetic antibacterial agent structurally related to oxolinic acid, has a broad spectrum of activity in vitro against gram-negative bacteria and considerable activity in vivo against infections with these bacteria. These observations led to studies on the absorption and excretion of miloxacin in mice, rats, and dogs after administration of a single oral dose. Studies on oxolinic acid have been included for comparison. Peak serum levels of miloxacin, attained 1 h after administration of 20, 50, and 100 mg/kg to rats and dogs, were approximately 20, 40, and 60 micrograms/ml, respectively. Peak levels in mice receiving the same dose were 15, 60, and 80 micrograms/ml at 0.5 h. Peak serum levels of oxolinic acid were attained 0.5 to 1 h later than the above times at comparable doses and were one-half to one-fourth those of miloxacin. Urinary recovery of miloxacin at the above doses ranged from 3.2 to 6.5% during the 24-h posttreatment period. Recoveries of oxolinic acid were one-half to one-fifth those of miloxacin. At a 50-mg/kg dose, rats excreted 4.6% of the miloxacin in bile in the 20-h posttreatment period.  相似文献   
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8.
OBJECTIVE: In this study, we evaluated the time course of the alterations in left ventricular (LV) dimensions, LV wall thickness, and LV systolic function in rats with endotoxemia by using echocardiography as well as myocardial histopathologic assessments. Our second goal was to examine whether pretreatment with a platelet-activating factor (PAF) antagonist would ameliorate the lipopolysaccharide (LPS)-induced cardiovascular collapse during the early phase. DESIGN: A prospective, controlled, in vivo animal laboratory study. SETTING: Research laboratory at a university. SUBJECTS: Male, Wistar rats (8-9 wks old; n = 83). INTERVENTIONS: In pentobarbital-anesthetized rats, the right carotid artery was cannulated to measure the arterial blood pressure and to sample blood. The right jugular vein also was catheterized for the administration of drugs. LPS (2 mg/kg) derived from Klebsiella pneumoniae or physiologic saline was administered in the presence or absence of pretreatment with TCV-309, a specific potent PAF antagonist. Echocardiographic studies were performed with an 8- to 13-MHz transducer. MEASUREMENTS AND MAIN RESULTS: LPS administration immediately induced progressive hypotension. The maximal hypotensive response was observed at 10 mins after LPS infusion with mean arterial pressure decreasing from 119 +/- 2 to 56 +/- 3 mm Hg (p < .001). LV end-diastolic internal dimensions decreased from 6.4 +/- 0.1 to 3.1 +/- 0.1 mm (p < .001) at 30 mins after LPS and remained significantly reduced compared with control rats. LV end-systolic dimensions also decreased dramatically from 3.5 +/- 0.2 to 0.5 +/- 0.1 mm (p < .001) at 30 mins after LPS and remained significantly reduced throughout the experiment. LV fractional shortening increased from 45 +/- 1% to 84 +/- 2% (p < .001) at 30 mins after LPS and remained elevated compared with control rats. LV wall thickness increased strikingly from 15 mins until 2 hrs after LPS infusion. Pathologic studies demonstrated marked congestion of capillaries and mild edema in the LV myocardium. The hematocrit increased after the administration of LPS. LPS markedly increased sympathetic tone as demonstrated by the elevation of plasma concentrations of epinephrine and norepinephrine. There was no elevation of concentrations of nitrite and nitrate. Pretreatment with TCV-309, a specific potent PAF antagonist, reduced LPS-induced hypotension and attenuated LV functional and structural changes. TCV-309 administration reduced the LPS-induced adrenergic activation and hemoconcentration. CONCLUSIONS: The hypotension that occurred during the initial phase of LPS-induced shock was accompanied by LV functional and structural alterations. The marked increase in LV wall thickness can be ascribed to the congestion of capillaries and edema in the LV myocardium. Pretreatment with a PAF antagonist reduced LPS-induced alterations. PAF may play a pivotal role during the initial phase of LPS-induced cardiovascular responses.  相似文献   
9.
BackgroundIntraoperative identification of small pulmonary nodules has been an important technical issue. We aimed to develop a new localization method which is much safer and simple procedure compared with conventional methods.MethodsThis was a retrospective study including patients with resected peripheral pulmonary nodules between November 2017 and April 2021 at Teikyo University School of Medicine, and Saitama Cardiovascular and Respiratory Center. All surgical procedure was wedge resection, and the tumor size was equal to or less than 20 mm which were detected by cone-beam computed tomography (CBCT; Philips Allura Xper FD 20, Philips). Some metal clips were put on several places of visceral pleura, where the target lesion was sandwiched by marking clips (sandwich marking technique). CBCT detected both the target lesion and metal clips, and video-assisted thoracoscopic surgery (VATS) was performed. Radiological and pathological findings were analyzed, and the correlation coefficient of tumor size was examined among pre-, intra-, and post-operative tumor sizes.ResultsThe average age of 90 patients was 65.2 years, and 47 were male (52.2%). All procedure was wedge resection including twelve bi-wedge resections, and one hundred nine peripheral pulmonary lesions were obtained by sandwich marking technique. The detection rate was 100%, and there was no marking-related complication.ConclusionsAll small peripheral pulmonary lesions were successfully detected and resected by using CBCT with no marking-related complication. Sandwich marking technique was demonstrated to provide safe, reliable, and simple localization procedure for small peripheral pulmonary lesions.  相似文献   
10.
Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in Western countries and is characterized by the clonal expansion of mature CD5+ B cells. There have been substantial advances in the field of CLL research in the last decade, including the identification of recurrent mutations, and clarification of clonal architectures, signaling molecules, and the multistep leukemogenic process, providing a comprehensive understanding of CLL pathogenesis. Furthermore, the development of therapeutic approaches, especially that of molecular target therapies against CLL, has markedly improved the standard of care for CLL. This review focuses on the recent insights made in CLL leukemogenesis and the development of novel therapeutic strategies.  相似文献   
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