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61.
Ultrastructural and phenotypic analysis of in vitro erythropoiesis from human cord blood CD34<Superscript>+</Superscript> cells 总被引:1,自引:0,他引:1
Erythropoietin (EPO) induces erythropoiesis in vitro as well as in vivo, and the process of erythroid differentiation has been explored phenotypically and morphologically. However, morphological analysis of in vitro erythropoiesis of human hematopoietic progenitor cells at the ultrastructural level has not been reported before. In the present study, we have traced the ultrastructural changes of erythroid differentiation during ex vivo expansion of human cord blood (CB) CD34(+) cells in the presence of EPO by electron microscopy (EM), along with concurrent phenotypic analysis. CD34(+) cells purified from ten CBs by immunomagnetic selection were cultured in serum-free essential media in the presence of a combination of the several cytokines including EPO, thrombopoietin, flt3-ligand (FL), stem cell factor (SCF), granulocyte colony-stimulating factor, interleukin (IL)-3 and/or IL-11. Phenotypic analysis was performed by flow cytometric analysis for erythroid markers, including glycophorin C (GPC), Kell-related, glycophorin A (GPA), band 3, Lu(b), and RhD. Ultrastructural analysis was performed by electron-microscopic examination of the cultured cells stained with uranyl acetate and lead citrate. Phenotypic analysis revealed that in the absence of EPO, genuine erythroid fraction expressing the typical pattern of erythroid markers did not appear. The order of the above markers expressed in the cultured cells in the presence of EPO was GPC, Kell-related, GPA, band 3, Lu(b), and RhD, irrespective of the type of cytokine added. Of the cytokines used in combination with EPO, FL + IL-3 was the most efficient in inducing erythroid differentiation, which was followed by SCF + IL-3. EM examination demonstrated complete process of erythroid development from pronormoblasts to reticulocytes with nuclei having been extruded and mature erythrocytes. These results suggest that morphologically intact erythrocytes could be produced by ex vivo expansion of CB CD34(+) cells using EPO. 相似文献
62.
Kentaro Ishii Ryo Ogino Yukinari Hosokawa Chiaki Fujioka Wataru Okada Ryota Nakahara Ryu Kawamorita Takuhito Tada Yoshiki Hayashi Toshifumi Nakajima 《Journal of radiation research》2015,56(1):141-150
The objectives of this study were to evaluate dosimetric quality and acute toxicity of volumetric-modulated arc therapy (VMAT) and daily image guidance in high-risk prostate cancer patients. A total of 100 consecutive high-risk prostate cancer patients treated with definitive VMAT with prophylactic whole-pelvic radiotherapy (WPRT) were enrolled. All patients were treated with a double-arc VMAT plan delivering 52 Gy to the prostate planning target volume (PTV), while simultaneously delivering 46.8 Gy to the pelvic nodal PTV in 26 fractions, followed by a single-arc VMAT plan delivering 26 Gy to the prostate PTV in 13 fractions. Image-guided RT was performed with daily cone-beam computed tomography. Dose–volume parameters for the PTV and the organs at risk (OARs), total number of monitor units (MUs) and treatment time were evaluated. Acute toxicity was assessed using the Common Terminology Criteria for Adverse Events, version 4.0. All dosimetric parameters met the present plan acceptance criteria. Mean MU and treatment time were 471 and 146 s for double-arc VMAT, respectively, and were 520 and 76 s for single-arc VMAT, respectively. No Grade 3 or higher acute toxicity was reported. Acute Grade 2 proctitis, diarrhea, and genitourinary toxicity occurred in 12 patients (12%), 6 patients (6%) and 13 patients (13%), respectively. The present study demonstrated that VMAT for WPRT in prostate cancer results in favorable PTV coverage and OAR sparing with short treatment time and an acceptable rate of acute toxicity. These findings support the use of VMAT for delivering WPRT to high-risk prostate cancer patients. 相似文献
63.
The learning curve in diagnosing acute appendicitis with emergency sonography among novice emergency medicine residents 下载免费PDF全文
64.
Sun Hwa Lee Seong Jong Yun Seokyong Ryu Seung Woon Choi Hye Jin Kim Tae Kyung Kang Sung Chan Oh Suk Jin Cho 《The Journal of emergency medicine》2018,54(5):607-614
Background
Neutrophil-to-lymphocyte ratio (NLR) has been used as a predictive marker for various conditions. However, there are no previous studies about NLR as a prognostic marker for acute infarction.Objective
To evaluate the potential utility of NLR as a predictor of acute infarction in acute vertigo patients without neurologic and computed tomography (CT) abnormalities.Methods
We conducted a prospective, observational study in the Emergency Department (ED) between January 2015 and December 2016. All patients underwent physical examination, laboratory tests, CT, and magnetic resonance imaging (MRI). Results of the initial and follow-up MRI with clinical progress note were considered as the reference standard. Statistically, multivariate logistic regression analysis and receiver operating characteristic (ROC) curve were used.Results
Thirty-five (25.9%) patients were diagnosed with acute infarction and 100 (74.1%) patients were diagnosed with peripheral vertigo. Horizontal nystagmus (p = 0.03; odds ratio 0.22) and NLR (p = 0.03; odds ratio 5.4) were significant factors for the differential diagnosis of acute infarction and peripheral vertigo. NLR > 2.8 showed the greatest area under the ROC curve (AUC; 0.819), optimal sensitivity (85.7%), and specificity (78.0%). NLR > 1.4 showed the highest sensitivity (97.1%) and relatively low specificity (41%). The absence of horizontal nystagmus increased the specificity (81.0%) and AUC (0.844).Conclusions
A combination of NLR > 2.8 and the absence of horizontal nystagmus is sufficiently specific for acute infarction in an ED patient with acute vertigo; thus, further testing with MRI is indicated. NLR < 2.8 by itself or combined with the presence of horizontal nystagmus is not sufficiently sensitive to rule out the need for further testing. 相似文献65.
In-Ae Chun So-Yeon Ryu Jong Park Hee-Kyung Ro Mi-Ah Han 《Nutrition Research And Practice》2015,9(4):425-432
BACKGROUND/OBJECTIVESFood insecurity has been suggested as being negatively associated with healthy behaviors and health status. This study was performed to identify the associations between food insecurity and healthy behaviors among Korean adults.SUBJECTS/METHODSThe data used were the 2011 Community Health Survey, cross-sectional representative samples of 253 communities in Korea. Food insecurity was defined as when participants reported that their family sometimes or often did not get enough food to eat in the past year. Healthy behaviors were considered as non-smoking, non-high risk drinking, participation in physical activities, eating a regular breakfast, and maintaining a normal weight. Multiple logistic regression and multinomial logistic regression analyses were used to identify the association between food insecurity and healthy behaviors.RESULTSThe prevalence of food insecurity was 4.4% (men 3.9%, women 4.9%). Men with food insecurity had lower odds ratios (ORs) for non-smoking, 0.75 (95% CI: 0.68-0.82), participation in physical activities, 0.82 (95% CI: 0.76-0.90), and eating a regular breakfast, 0.66 (95% CI: 0.59-0.74), whereas they had a higher OR for maintaining a normal weight, 1.19 (95% CI: 1.09-1.30), than men with food security. Women with food insecurity had lower ORs for non-smoking, 0.77 (95% CI: 0.66-0.89), and eating a regular breakfast, 0.79 (95% CI: 0.72-0.88). For men, ORs for obesity were 0.78 (95% CI: 0.70-0.87) for overweight and 0.56 (95% CI: 0.39-0.82) for mild obesity. For women, the OR for moderate obesity was 2.04 (95% CI: 1.14-3.63) as compared with normal weight.CONCLUSIONSFood insecurity has a different impact on healthy behaviors. Provision of coping strategies for food insecurity might be critical to improve healthy behaviors among the population. 相似文献
66.
67.
Yasuharu Matsunaga-Lee MD Yasuyuki Egami MD Kohei Ukita MD Akito Kawamura MD Hitoshi Nakamura MD Yutaka Matsuhiro MD Koji Yasumoto MD Masaki Tsuda MD Akihiro Tanaka MD Naotaka Okamoto MD Masamichi Yano MD PhD Ryu Shutta MD Yasushi Sakata MD PhD FACC FESC Masami Nishino MD PhD FACC FESC Jun Tanouchi MD PhD 《Journal of cardiovascular electrophysiology》2021,32(1):58-66
68.
Kon Hong Kim Chun Ki Sung Bae Geun Park Woo Gil Kim Sang Kun Ryu Kang Sung Kim In Sik Paik Chang Han Oh 《Journal of hepato-biliary-pancreatic sciences》1998,5(3):303-308
In the Far East, hepatic resection is the definitive treatment for complicated intrahepatic stones (IHS). However, many investigators have reported that the associated intrahepatic biliary stricture is the main cause of treatment failure. A retrospective comparative study was undertaken to clarify the long-term efficacy of hepatic resection for treatment of IHS and to investigate the clinical significance of intrahepatic biliary stricture in treatment failure after hepatic resection performed in 44 patients with symptomatic IHS. The patients were divided into two study groups: group A, with intrahepatic biliary stricture (n = 28) and group B, without stricture (n = 16). Residual or recurrent stones, recurrence of intrahepatic biliary stricture, late cholangitis, and final outcomes were analyzed and compared statistically between the two groups. The patients were followed up for a median duration of 65 months after hepatectomy. The overall incidence of residual or recurrent stones was 36% and 11%, respectively, in groups A and B. The initial treatment failure rate was 50% in group A and 31% in group B. Intrahepatic biliary stricture recurred in 46% of patients in group A, while none of the group B patients had biliary stricture recurrence (P = 0.001). More than two-thirds of the restrictures in group A were identified at the primary site. The incidence of late cholangitis was higher in group A (54%) than in group B (6%) (P = 0.002). Three-quarters of the patients with cholangitis in group A had severe cholangitis, that was recurrent, and related to stones and strictures (n = 11). They and 2 asymptomatic patients in group B required secondary procedures done at a median of 12 months after hepatectomy. Final outcomes after hepatectomy with or without secondary management were good in 80%, fair in 16%, and poor in 4% of our 44 patients. Most recurrent cholangitis after hepatectomy in patients with IHS was related to recurrent intrahepatic ductal strictures. Therefore, to be effective, hepatic resection should include the strictured duct. However, with hepatectomy alone it is difficult to clear the IHS or relieve the ductal strictures completely, particularly in patients with bilateral IHS, so perioperative team approaches that include both radiologic and cholangioscopic interventions should be combined for the effective management of IHS. 相似文献
69.
Izuishi K Ryu M Hasebe T Kinoshita T Konishi M Inoue K 《Hepato-gastroenterology》2000,47(34):1122-1124
We report on a 50-year-old man with a liver mass that, when surgically resected, was found to be a hepatocellular carcinoma that had undergone spontaneous complete necrosis without previous treatment. Histologically, no viable tumor cells were observed. The postoperative course was uneventful, and the patient is alive without evidence of recurrence about 5 years after surgery. Spontaneous total necrosis of hepatocellular carcinoma without previous treatment is rare. In particular, spontaneous total necrosis of a hepatocellular carcinoma that has been proven by histologic examination of a surgically resected liver specimen is extremely rare; only three cases of spontaneous complete necrosis of hepatocellular carcinoma have been reported previously. In this report, we present our unusual case and discuss possible causes of spontaneous total necrosis or regression of hepatocellular carcinoma. 相似文献
70.
BACKGROUND: Follicular bronchiolitis is a histopathologic finding that occurs in diverse clinical contexts. The current study was conducted to characterize clinico-radiologic features, and assess outcomes associated with follicular bronchiolitis. SUBJECTS AND METHODS: Twelve subjects with follicular bronchiolitis on lung biopsy were seen over a 9-year period, between 1996 and 2005. Medical records, biopsy and radiographic findings, and details of outcome at the time of last follow-up were recorded. RESULTS: The study population included 4 men and 8 women; the median age at diagnosis was 54 years (range, 33-81 years). Four patients had underlying systemic diseases that included: 2 with common variable immunodeficiency, 1 Sj?gren's syndrome and 1 undifferentiated connective tissue disease. The diagnosis was obtained by surgical lung biopsy in all cases. Follicular bronchiolitis was the major histologic pattern in 9 patients; organizing pneumonia, nonspecific interstitial pneumonia and usual interstitial pneumonia was seen in 1 patient each with follicular bronchiolitis being an associated secondary histopathologic component. Computed tomographic findings included reticular opacities, small nodules and ground-glass opacities. Clinical course was characterized by relative stability with partial response to immunosuppressive agents. During a median follow-up period of 47 months, only one death occurred--out of 9 patients where the outcome information was available--and was unrelated to lung disease. CONCLUSIONS: The histologic lesion of follicular bronchiolitis may be seen as the predominant finding or a relatively minor feature in interstitial pneumonias. The clinical course and prognosis for most patients with follicular bronchiolitis is relatively good, and progressive lung disease is uncommon. 相似文献