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81.
82.
Rubinder Birk Dominick Shaw Cheika Kennedy Yutaro Higashi Roma Patel Ayushman Gupta Iain Au-Yong 《Current problems in diagnostic radiology》2021,50(5):656-661
PurposeCritically ill patients with coronavirus disease 2019 (COVID-19) are at increased risk of thrombosis. There are limited data on PE rates in COVID-19 patients at presentation to the emergency department (ED). In this study, we evaluated the detection rates of PE in patients presenting to the ED with suspected and proven COVID-19.MethodsA single-centre retrospective study was undertaken of 285 consecutive patients undergoing CT pulmonary angiogram (CTPA) in the Emergency Department at Nottingham University Hospitals NHS Trust in the United Kingdom between 25 March and 30 April 2020. At our institution, CTPA is performed in all patients undergoing CT for triage. The study group consisted of patients considered COVID-19 positive based on polymerase chain reaction (PCR) results and CTPA findings. The detection rate of PE in COVID-19 patients was compared to patients undergoing CTPA for suspected PE only and for suspected COVID-19 with no COVID CT findings and negative PCR (control group 1); and CTPAs prior to the coronavirus pandemic (control group 2).ResultsOne of 48 patients in the study group had a PE (2%) compared to 25/215 (12%) in control group 1 and 10/50 (20%) in control group 2. Prevalence of PE in the study group was lower than in control group 1 (P = 0.058) and compared to control group 2 (P = 0.005). Eleven patients undergoing CTPA had negative PCR but positive CT for COVID-19.ConclusionDetection rate of pulmonary embolus is low in patients with COVID-19 undergoing CTPA on a triage pathway. 相似文献
83.
Osamu Seguchi Tomoyuki Fujita Yoshihiro Murata Masanobu Yanase Masahiro Higashi Koichi Toda Takeshi Nakatani 《Journal of artificial organs》2013,16(2):258-262
Infections associated with left ventricular assist devices (LVADs) constitute an important clinical issue because they are difficult to completely eradicate without removal of the LVAD itself and can sometimes be fatal. We encountered a case of extracorporeal LVAD-related candida infection in a patient who was successfully weaned from LVAD support. Although the patient appeared to have recovered from the infection, the patient was readmitted to our institute due to a relapse of candida infection 9 months after LVAD removal. Although the patient did not demonstrate any systemic sign of infection on admission, computed tomography images clearly showed that the residual apical cuff of the LVAD inflow cannula, which was infected with Candida albicans during the initial admission, resulted in re-infection that involved the chest wall with destruction of the adjacent rib. 相似文献
84.
Koichi Kimura Eisuke Adachi Ayako Toyohara Sachie Omori Kaoru Ezaki Ryo Ihara Takahiro Higashi Kippei Ohgaki Shuhei Ito Shin-ichiro Maehara Toshihiko Nakamura Fumiyoshi Fushimi Yoshihiko Maehara 《World Journal of Clinical Cases》2021,9(17):4453-4459
BACKGROUNDSchwannoma of the pancreas is extremely rare. We report a case of pancreatic schwannoma that was difficult to distinguish from pancreatic carcinoma before surgery.CASE SUMMARYA 66-year-old male underwent a right-lobe hepatectomy for hepatocellular carcinoma. Post-surgical computed tomography showed a 10 mm long solid mass with ischemia, with no expansion into the main pancreatic duct. Upon magnetic resonance cholangiopancreatography, the tumor had high signal intensity in diffusion weighted images, consistent with pancreatic carcinoma. Endoscopic ultrasound (EUS) was performed to obtain more information about the tumor, and showed a 14 mm solid and hypoechoic mass in the pancreatic body. Contrast enhanced EUS revealed that the tumor showed a hyperechoic mass in the early phase, and the contrasting effect continuation was very short; findings also consistent with pancreatic carcinoma. Thus, we preoperatively diagnosed his condition as a pancreatic carcinoma and performed distal pancreatectomy with splenectomy. Microscopic examination showed that the tumor was in fact a benign schwannoma. Histology showed a proliferation of spindle-shaped cell in a vague fascicular and haphazard pattern, with palisading arrangement.CONCLUSIONSchwannoma of the pancreas is very rare, however, clinicians should consider schwannoma as the differential diagnosis for pancreatic tumors. 相似文献
85.
86.
Prevention of recurrence of esophageal varices after endoscopic injection sclerotherapy with ethanolamine oleate 总被引:2,自引:0,他引:2
Endoscopic injection sclerotherapy was given to 155 patients with esophageal varices mainly related to non-alcoholic liver cirrhosis. The formation of a superficial ulcer in the lower esophagus was achieved in 141 (91.0%) of the 155 patients, with an average of 4.1 sessions of endoscopic injection sclerotherapy during an average time of 4.9 weeks. The average volume of 5% ethanolamine oleate sclerosant used was 24.8, 19.2, 12.3 and 6.5 ml for the initial to fourth sessions of endoscopic injection sclerotherapy, respectively. For 14 patients, a sufficient number of sessions of endoscopic injection sclerotherapy could not be given: 10 early deaths (5 hepatoma, 4 liver failure and 1 gastric bleeding), and 4 refused further sessions. When the esophageal mucosa had been eliminated and a superficial ulcer had formed, episodes of recurrent bleeding or recurrence of esophageal varices were nil over a median follow-up of 14.6 months, with a range of 1 to 27 months. In seven patients, bleeding recurred before elimination of the mucosa could be achieved, but these bleeding episodes were well controlled with an additional session of endoscopic injection sclerotherapy. At the time of analysis, there were 36 deaths (20 hepatoma, 14 liver failure and 2 gastric bleeding) among these 155 patients. Thus, the mean follow-up was 16.3 months (range: 7 to 27 months) in the 119 survivors, with no recurrence of the varices. We propose that removal of the esophageal mucosa may well be the endpoint of repeated endoscopic injection sclerotherapy in the management of patients on injection sclerotherapy. 相似文献
87.
Naohisa Ibuki Kazuhide Yamamoto Kazuhisa Yabushita Nobuaki Okano Ryoichi Okamoto Noriaki Shimada Tomomi Hakoda Motowo Mizuno Toshihiro Higashi Takao Tsuji 《Liver international》2002,22(3):198-204
Abstract: Background/Aims: The molecular mechanism involved in hepatocellular injury in viral hepatitis remains to be clarified. Methods: We investigated the in situ expression of effector molecules of cytotoxic T lymphocytes such as Fas‐ligand (Fas‐L), perforin and Granzyme B (Gr‐B) immunohistochemically in liver tissues from 20 patients with chronic hepatitis B (CHB) and C (CHC). The degree of cell infiltration was analysed semi‐quantitatively and compared with the histological activity index (HAI). Fas‐L was expressed in both CD4 and CD8 T‐cells in the portal tract as well as in the parenchyma. Results: Immunostaining of serial sections demonstrated that mononuclear cells at interface hepatitis and focal necrosis were mainly Fas‐L positive CD8 T‐cells. On the other hand, the expression of perforin or Gr‐B was limited to a few mononuclear cells in the portal tract and parenchyma. Semi‐quantitative analysis showed a positive correlation between HAI and the grade of infiltration of CD8 T‐cells or Fas‐L‐positive cells, while the correlation was not apparent between HAI and the number of Gr‐B positive cells. The expression of these molecules was not different between types of viruses. Conclusions: These results suggest that Fas‐L‐positive CD8 T‐cells play a major role in the pathogenesis of liver cell injury in chronic hepatitis. 相似文献
88.
Higashi Y Sasaki S Nakagawa K Ueda T Yoshimizu A Kurisu S Matsuura H Kajiyama G Oshima T 《Journal of the American College of Cardiology》2000,35(2):284-291
OBJECTIVES: The purpose of this study was to compare the effect of different antihypertensive agents, calcium antagonists, angiotensin-converting enzyme (ACE) inhibitors, beta-blockers and diuretic agents on endothelial function. BACKGROUND: Endothelial dysfunction is a component of essential hypertension, and various antihypertensive drugs may be able to restore normal function. METHODS: Forearm blood flow (FBF) was measured in 296 patients with essential hypertension, including 46 untreated subjects using strain-gauge plethysmography during reactive hyperemia and after sublingual administration of nitroglycerin (NTG). Forty-seven normotensive subjects were similarly evaluated as control subjects. RESULTS: The FBF during reactive hyperemia in the 296 hypertensive patients was significantly less than that in age-matched normotensive subjects. The increase in FBF after administration of sublingual NTG was similar in both groups. Systolic and diastolic blood pressures and forearm vascular resistance were greater in the untreated group than in the four treated groups and did not differ with respect to the antihypertensive agent used. The maximal FBF response from reactive hyperemia was significantly greater in the ACE inhibitor-treated group than in the group treated with calcium antagonists, beta-blockers, diuretic agents, or nothing (40.5 +/- 5.2 vs. 32.9 +/- 5.8, 34.0 +/- 5.6, 32.1 +/- 5.9, and 31.9 +/- 5.8 ml/min per 100 ml tissue, p < 0.05, respectively). Reactive hyperemia was similar in the calcium antagonist, beta-blocker, diuretic and untreated groups, and changes in FBF after sublingual NTG administration were similar in all groups. The infusion of NG-monomethyl-L-arginine, a nitric oxide (NO) synthase inhibitor, abolished the enhancement of reactive hyperemia in hypertensive patients treated with ACE inhibitors. CONCLUSIONS: These findings suggest that ACE inhibitors augment reactive hyperemia, an index of endothelium-dependent vasorelaxation, in patients with essential hypertension. This augmentation may be due to increases in NO. 相似文献
89.
Katherine Sellers Matthew P. Fox Michael Bousamra II Stephen P. Slone Richard M. Higashi Donald M. Miller Yali Wang Jun Yan Mariia O. Yuneva Rahul Deshpande Andrew N. Lane Teresa W.-M. Fan 《The Journal of clinical investigation》2015,125(2):687-698
Anabolic biosynthesis requires precursors supplied by the Krebs cycle, which in turn requires anaplerosis to replenish precursor intermediates. The major anaplerotic sources are pyruvate and glutamine, which require the activity of pyruvate carboxylase (PC) and glutaminase 1 (GLS1), respectively. Due to their rapid proliferation, cancer cells have increased anabolic and energy demands; however, different cancer cell types exhibit differential requirements for PC- and GLS-mediated pathways for anaplerosis and cell proliferation. Here, we infused patients with early-stage non–small-cell lung cancer (NSCLC) with uniformly 13C-labeled glucose before tissue resection and determined that the cancerous tissues in these patients had enhanced PC activity. Freshly resected paired lung tissue slices cultured in 13C6-glucose or 13C5,15N2-glutamine tracers confirmed selective activation of PC over GLS in NSCLC. Compared with noncancerous tissues, PC expression was greatly enhanced in cancerous tissues, whereas GLS1 expression showed no trend. Moreover, immunohistochemical analysis of paired lung tissues showed PC overexpression in cancer cells rather than in stromal cells of tumor tissues. PC knockdown induced multinucleation, decreased cell proliferation and colony formation in human NSCLC cells, and reduced tumor growth in a mouse xenograft model. Growth inhibition was accompanied by perturbed Krebs cycle activity, inhibition of lipid and nucleotide biosynthesis, and altered glutathione homeostasis. These findings indicate that PC-mediated anaplerosis in early-stage NSCLC is required for tumor survival and proliferation. 相似文献
90.
Taizo Furukawa Shigeyoshi Aoi Kohei Sakai Mayumi Higashi Shigehisa Fumino Tatsuro Tajiri 《Asian journal of endoscopic surgery》2015,8(4):473-476
Omental lipoblastoma is extremely rare among benign tumors. We herein report the case of a child who underwent laparoscopic extirpation of a large omental lipoblastoma. A 4‐year‐old girl was diagnosed with an intra‐abdominal solid tumor. Abdominal imaging revealed a fat density mass that was well encapsulated and measured 18 × 15 × 7.5 cm in size. Considering the MRI findings and movability of the tumor, we strongly suspected that the lesion was an omental lipoblastoma. We initially decided to perform laparoscopic exploration and, if possible, extirpation of the solid tumor sequentially. A total of five trocars were used, and the tumor was found to originate from the omentum. We successfully performed complete resection of the tumor laparoscopically. A histological examination revealed lipoblastoma. For large abdominal tumors in children, the laparoscopic approach is recommended as the first procedure when the tumor is preoperatively considered to be benign and resectable. 相似文献