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991.
Shin Ae Lee Sang Young Han Eun Joo Lee Byung Pyo Kwon In Young Koh Hae Jong Choi Min Chan Kim Jin Han Cho 《Taehan Sohwagi Hakhoe chi》2006,48(6):427-430
Splenic pseudocyst is a rare complication of abdominal trauma. Although it is rare, splenic pseudocyst is well-documented in the literature. According to the current classification, approximately 30% of all splenic cysts or pseudocysts result from direct abdominal trauma. In addition, chronic pancreatitis leads to change of nearby organs with possible acute and chronic complications including splenic lesions. This unusual complication can occur in both emergent and non-emergent conditions. The useful diagnostic procedures to assess intrasplenic pseudocyst are sonogram, CT scan, splenic scan, and occasionally angiography. However, definite diagnosis of pseudocyst is possible only after splenectomy when the absence of epithelial lining is confirmed histologically. Splenic pseudocyst requires surgical resection. We experienced a 31-year-old man who confirmed of warmness in the left side of back with left upper quadrant abdominal pain for several months. First impression was splenic lymphangioma based on CT scan and sonogram finding. Splenectomy was performed. Microscopic examination revealed splenic pseudocyst with fibrous capsule without epithelial lining. 相似文献
992.
Jong-Won Ha Seung-Yun Cho Namsik Chung Dong-Hoon Choi Byung-Joo Choi Yangsoo Jang Won-Heum Shim Sung-Soon Kim 《Journal of the American Society of Echocardiography》2002,15(5):389-395
A well-developed collateral circulation is frequently observed in patients with total coronary occlusion. However, the fate of the collateral circulation after successful percutaneous transluminal coronary angioplasty (PTCA) has not been fully characterized. The purpose of this study was to compare the efficacy of coronary angiography and myocardial contrast echocardiography (MCE) in the evaluation of the collateral circulation after PTCA and to assess the temporal changes of the collateral circulation after successful PTCA of a totally occluded artery by using these 2 diagnostic methods. The study group was comprised of 20 consecutive patients (16 male, mean age 54 years) who underwent elective PTCA for total coronary occlusion. Coronary angiography was performed before, immediately after, and 24 hours after PTCA. MCE was also performed before, immediately after, and 24 hours after PTCA, by the intracoronary injection of sonicated radiographic contrast medium. According to the angiographic findings, the collateral circulation was graded on a scale of 0 to 3 as follows: 0 = no visible filling; 1 = collateral filling of side branches; 2 = partial collateral filling of the epicardial artery; 3 = complete filling of the epicardial artery. By MCE, myocardial perfusion by the collateral circulation was assessed by scoring the contrast pattern of collateral-dependent myocardial segments as follows: 0 = none; 0.5 = patchy or epicardial; 1 = homogeneous. The left anterior descending artery was occluded in 12 patients and the right coronary artery in 8 patients. Coronary angiographic collateral grades before PTCA were grade 2 in 5 patients and grade 3 in 15. PTCA with stenting was successfully performed in all patients without significant residual stenosis. Coronary angiography showed collateral circulation disappeared after PTCA in all patients. However, residual collateral perfusion was observed in 7 patients by MCE, performed immediately after PTCA (score 1 in 3 patients; score 0.5 in 4 patients). This residual collateral perfusion could be demonstrated even 24 hours after PTCA by MCE in 3 patients (all patients were 0.5 in myocardial perfusion score). In conclusion, successful PTCA with stenting of a totally occluded coronary artery leads to a disappearance of collateral vessels by coronary angiography in most of the patients. However, although angiographically not visible, coronary collateral circulation may persist even 24 hours after successful PTCA of a totally occluded artery demonstrated by MCE. 相似文献
993.
Alavala Matta Reddy Byung Kook Kwak Hyung Jin Shim Chiyoung Ahn Sun Hang Cho Byung Jin Kim Sang Young Jeong Sung‐Joo Hwang Soon Hong Yuk 《CONTRAST MEDIA & MOLECULAR IMAGING》2009,4(3):118-126
Magnetic resonance imaging of cells labeled with superparamagnetic iron oxide (SPIO) could be a valuable tool for tracking transplanted cells in living organisms. Human bone marrow‐derived mesenchymal stem cells (hBMMSC) were labeled with a novel polyvinyl pyrrolidone (PVP)‐coated SPIO. Prussian blue staining and electron microscopy revealed that almost all of the cells were efficiently labeled with PVP–SPIO nanoparticles. There were no signs of cytotoxicity, even at concentrations of up to 1600 µg Fe/ml of the nanoparticles, and the labeled cells were successfully visualized by in vitro cellular MRI. In addition, there was no significant alteration of the phenotype or the adipo/osteo/chondrogenic differentiation potential of the cells. This was in contrast to Feridex IV labeling that led to the inhibition of hBMMSC chondrogenesis. Following intramuscular injection in a rabbit hind limb ischemia model, the intercellular migration of the labeled cells toward the ablated site was clearly tracked through in vivo MRI. The localization of the transplanted cells observed by MRI correlated well with postmortem histological studies. These results demonstrate that the novel PVP–SPIO nanoparticles appear to be efficient MR contrast agents and may enable non‐invasive in vivo tracking of stem cells in experimental and clinical settings during cell therapy. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
994.
Jung YO Min SY Cho ML Park MJ Jeon JY Lee JS Oh HJ Kang CM Park HS Park KS Cho SG Park SH Kim HY 《Immunology letters》2007,111(2):76-83
To investigate the role of CD8alpha(+) DCs in the development of collagen-induced arthritis (CIA). The immunogenic properties of CD8alpha(+) and CD8alpha(-) DC subsets were investigated by mixed-lymphocyte reaction and cytokine enzyme-linked immunoassay. CII-pulsed CD8alpha(+) DCs or CD8alpha(-) DCs with CD4(+) T cells from CIA mice were adoptively transferred onto the hind footpad of DBA mice. The onset of arthritis and the arthritis index were examined for 14 weeks after adoptive transfer. Expression of MHC-II and CD80 but not CD86 and CD40 was higher in CD8alpha(+) DCs than in CD8alpha(-) DCs from the spleens of CIA mice. Culturing CD8alpha(+) DCs with CD4(+) T cells significantly increased the proliferative response of CD4(+) T cells in the presence of CII. The production of interleukin (IL)-12p70, IL-17, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha was slightly increased in CD8alpha(+) DCs than in CD8alpha(-) DCs. DBA/1 mice that were adoptively transferred with CII-pulsed CD8alpha(+) DCs and CD4(+) T cells into the footpads showed accelerated onset of CIA compared to control group. By contrast, CD8alpha(-) DCs showed a partial inhibitory effect on CIA. These findings show that CD8alpha(+) DCs accelerated the onset of CIA when aoptively transferred with CD4(+) T cells and that CD8alpha(+) DCs provoke the development of CIA probably by stimulating the immune responses of CII-reactive CD4(+) T cells and by increasing the production of inflammatory cytokines. 相似文献
995.
Sang-Hyun Cho Dong Gyu Kim Dae-Shik Kim Yun-Hee Kim Chu-Hee Lee Sung Ho Jang 《Neuroscience letters》2007
Diffusion tensor tractography (DTT) is useful for exploring the state of the corticospinal tract (CST). An accurate estimation of the integrity of the CST in the early stage of a cerebral infarct would enable a determination of motor recovery. DTT was performed to classify CST integrity following a corona radiata infarct to evaluate if the procedure could characterize the motor outcome of the affected hand. Fifty-five patients with completely paralyzed hands due to a corona radiata infarct were recruited for the study, and DTT images were obtained within 7–30 days after a stroke. The DTI findings for the patients were classified into four groups. In type A, the CST was preserved around the infarct; in type B, the CST originated from a cortex other than the primary motor cortex; in type C, the CST was interrupted at the infarct; in type D, the CST failed to reach the infarct due to degeneration. Six months after a stroke, the motor function of the affected hand was evaluated with the motricity index (MI) for the hand, the Medical Research Council score (MRC) for finger extensors and the modified Brunnstrom classification (MBC). These indices were significantly influenced by the DTT type (p < 0.05). The highest MI, MRC and MBC were seen in the DTT type A patients; the lowest MI, MRC and MBC were seen in the DTT type D patients (p < 0.05). The integrity of the corticospinal tract determined by DTT obtained during the early stage of a corona radiata infarct seems to be helpful in predicting the motor outcome of the affected hand. 相似文献
996.
Geddes K Rubino S Streutker C Cho JH Magalhaes JG Le Bourhis L Selvanantham T Girardin SE Philpott DJ 《Infection and immunity》2010,78(12):5107-5115
The pattern recognition molecules Nod1 and Nod2 play important roles in intestinal homeostasis; however, how these proteins impact on the development of inflammation during bacterial colitis has not been examined. In the streptomycin-treated mouse model of Salmonella colitis, we found that mice deficient for both Nod1 and Nod2 had attenuated inflammatory pathology, reduced levels of inflammatory cytokines, and increased colonization of the mucosal tissue. Nod1 and Nod2 from both hematopoietic and nonhematopoietic sources contributed to the pathology, and all phenotypes were recapitulated in mice deficient for the signaling adaptor protein Rip2. However, the influence of Rip2 was strictly dependent on infection conditions that favored expression of the Salmonella pathogenicity island 2 (SPI-2) type III secretion system (TTSS), as Rip2 was dispensable for inflammation when mice were infected with bacteria grown under conditions that promoted expression of the SPI-1 TTSS. Thus, Nod1 and Nod2 can modulate inflammation and mediate efficient clearance of bacteria from the mucosal tissue during Salmonella colitis, but their role is dependent on the expression of the SPI-2 TTSS. 相似文献
997.
Talbot K Cho DS Ong WY Benson MA Han LY Kazi HA Kamins J Hahn CG Blake DJ Arnold SE 《Human molecular genetics》2006,15(20):3041-3054
Variations in the gene encoding the novel protein dysbindin-1 (DTNBP1) are among the most commonly reported genetic variations associated with schizophrenia. Recent studies show that those variations are also associated with cognitive functioning in carriers with and without psychiatric diagnoses, suggesting a general role for dysbindin-1 in cognition. Such a role could stem from the protein's known ability to affect neuronal glutamate release. How dysbindin-1 might affect glutamate release nevertheless remains unknown without the discovery of the protein's neuronal binding partners and its subcellular locus of action. We demonstrate here that snapin is a binding partner of dysbindin-1 in vitro and in the brain. Tissue fractionation of whole mouse brains and human hippocampal formations revealed that both dysbindin-1 and snapin are concentrated in tissue enriched in synaptic vesicle membranes and less commonly in postsynaptic densities. It is not detected in presynaptic tissue fractions lacking synaptic vesicles. Consistent with that finding, immunoelectron microscopy showed that dysbindin-1 is located in (i) synaptic vesicles of axospinous terminals in the dentate gyrus inner molecular layer and CA1 stratum radiatum and in (ii) postsynaptic densities and microtubules of dentate hilus neurons and CA1 pyramidal cells. The labeled synapses are often asymmetric with thick postsynaptic densities suggestive of glutamatergic synapses, which are likely to be derived from dentate mossy cells and CA3 pyramidal cells. The function of dysbindin-1 in presynaptic, postsynaptic and microtubule locations may all be related to known functions of snapin. 相似文献
998.
Objective: To study the neurotoxicity induced by Ricinus communis agglutinin (RCA), ricin A chain (RTA), and trichosanthin (TCS) in vitro. Methods: Rat neurons and Schwann cells were cultured and real-time up-take of RIPs was traced. TUNEL, Annexin V and DAPI were employed to study the mechanism. Results: The purity of both primary neuronal and Schwann cell cultures attained 80–90%. In neuritis, transport of FITC-RCA was demonstrated, but RTA and TCS were not detected. RCA elicited the strongest TUNEL and annexin V signals in both cultures. RTA evoked a stronger apoptotic signal than TCS in neurons. In contrast, compared with TCS, RTA elicited an attenuated apoptotic reaction in Schwann cells. All internalized RIPs were concentrated in the cytoplasm of the cells and their nuclei were not stained by DAPI. Conclusion: The toxicity of these RIPs on neurons is different from that on Schwann cells. Although they enter cells by different mechanisms they all induce apoptosis. These results may find application in in vivo neural lesioning studies and clinical therapy. 相似文献
999.
Acoustic pharyngometry is a relatively new noninvasive method that quantifies geometrically complexed pharyngeal dimensions. Our study aimed to investigate the predictability and usefulness of acoustic pharyngometry in diagnosis of obstructive sleep apnea (OSA), and we developed a prospective clinical trial in 16 subjects without apnea and 54 subjects with apnea. All seventy subjects received polysomnography (PSG) to assess the sleep architecture, including breathing and the degree of apnea hypopnea index. Acoustic pharyngometry was performed in four body positions (sitting, supine, right and left lateral) while awake with tidal breathing in addition to morphometric measurements (Kushida index) of oral cavity. This study shows that the cross-sectional area and volume of the upper airway is smaller in the supine position than any other positions. As well, the oropharyngeal junction area of the supine position is the most predictive parameter to discriminate between subjects with or without OSA. Acoustic pharyngometry can be a clinically useful tool for localizing the narrowed portion of the upper airway and predicting obstructive sleep apnea. 相似文献
1000.
Seizure is an uncommon complication of coronavirus disease 2019 (COVID-19). The frequency and characteristics of new-onset seizures in hospitalized patients with COVID-19 were investigated. Of a total of 1,487 patients with confirmed COVID-19, six (0.4%) developed new-onset seizures. All six had severe or critical COVID-19 requiring intensive care and mechanical ventilation or high-flow oxygen therapy. Among COVID-19 patients admitted to the intensive care unit (n = 169), the incidence of new-onset seizures was 3.6%. Underlying structural lesions (acute infarction and remote hemorrhage), hypoxia, sepsis, and metabolic derangements were associated with the development of seizures. Of the six patients, three patients died, and, at the time of discharge, one patient had a severe disability, while the remaining two were well recovered. 相似文献