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71.
Secretory meningioma have been described as a distinct variant of meningioma based on their histologic, immunohistochemical and ultrastructural features of epithelial and secretory differentiation of meningothelial cells with accumulation of secretory material in the form of hyaline inclusion. Secretory meningioma is also a benign tumor having similar biological behaviour to that of typical meningiomas: hence, it is important for it to be recognized and diagnosed correctly to avoid unnecessary radiation and chemotherapy. Here we present a case of secretory meningioma with typical morphologic features. The patient was a 56-year-old woman with bilateral visual disturbance. A well-circumscribed mass was present in the left frontal lobe of cerebrum with surrounding edema. The tumor was composed of whorls of meningothelial cells and abundant intra- and extracellular eosinophilic hyaline inclusions which showed immunoreactivity for epithelial membrane antigen(EMA) and carcinoembryonic antigen(CEA). Ultrastructural features also supported epithelial and secretory differentiation of tumor cells. 相似文献
72.
Min-Seok Rha Hye Won Jeong Jae-Hoon Ko Seong Jin Choi In-Ho Seo Jeong Seok Lee Moa Sa A Reum Kim Eun-Jeong Joo Jin Young Ahn Jung Ho Kim Kyoung-Ho Song Eu Suk Kim Dong Hyun Oh Mi Young Ahn Hee Kyoung Choi Ji Hoon Jeon Jae-Phil Choi Eui-Cheol Shin 《Immunity》2021,54(1):44-52.e3
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73.
Paul McIntosh Andrew P. Southan Sobia Akhtar Christina Sidera Yuri Ushkaryov J. Oliver Dolly B. Robertson 《Pflügers Archiv : European journal of physiology》1997,435(1):43-54
We have examined the effects of co-expression of Kvβ1.1 and Kvβ2.1 subunits on the gating of rat brain Kv1.4 channels, expressed
in Xenopus oocytes. Expression of Kv1.4 subunits alone produced a rapidly inactivating ”A” type current, which activated at potentials
beyond –60 mV in a solution containing high levels of rubidium. Current activation curves obtained from tail current measurements
were fitted with a Boltzmann function, with V
1/2 = –47 mV and k = 10 mV. Neither the Kvβ1.1 nor Kvβ2.1 subunits altered the voltage dependence of activation. Both subunits accelerated the
activation time constant of Kv1.4, without affecting its voltage dependence. Surprisingly, the Kvβ2.1 subunit, which lacks
an N-terminal inactivation domain, was almost as effective as the Kvβ1.1 subunit in speeding up Kv1.4. Steady-state inactivation
of Kv1.4 was unchanged upon co-expression with either Kvβ1.1 or Kvβ2.1 subunits. Kv1.4 recovered from inactivation with two
time constants; apart from an ≈ 50% lengthening of the slow time constant with a high Kvβ2.1 injection ratio, neither time
constant was altered by either the Kvβ1.1 or Kvβ2.1 subunits, suggesting little interaction with recovery from C-type inactivation.
Clearly, β subunits have the potential to modify the gating of Kv1.4 channels in the brain more subtly than has been suggested
previously.
Received: 17 March 1997 / Accepted: 30 June 1997 相似文献
74.
H. J. Jeong S. W. Hong Y. S. Kim M. S. Kim I. H. Choi K. Park I. J. Choi 《Journal of Korean medical science》1996,11(6):489-494
To investigate the characteristics of interstitial inflammatory cells and possible involvement of nudelta T cells, 16 renal allograft biopsies showing chronic rejection were stained by immunohistochemical method and correlated with the data of peripheral blood evaluated by flow cytometry. For immunophenotyping, fresh frozen sections were stained with monoclonal antibodies against CD3, CD4, CD8, CD68, CD56, TCRdelta1 and HLA DR. Paraffin embedded tissue was stained with CD45RO, CD20-Cy and CD68. Nine cases of nonspecific tubulointerstitial change and 4 cases of nonallograft tubulointerstitial nephritis were used as a control. Inflammatory infiltration was present in all cases studied. T cells predominated in the interstitium of chronic rejection and were followed by macrophages and B cells. The degree of interstitial infiltration of frozen section was not accordant with that of paraffin sections. Allografts with nonspecific tubulointerstitial changes or tubulointerstitial nephritis of native kidneys showed similar distribution pattern in terms of type and degree. However, the degree of infiltrate did not give any statistical significance among groups. The CD4/CD8 ratios in interstitial infiltrates were less than 1.0 in 6 cases and was not accordant with those of peripheral blood. Proportion of nudelta T cells increased over 10% in 2 cases in tissue and in 3 cases in peripheral blood. In 3 cases of chronic rejection in which both tissue and blood results were available, there was no concordance of CD4/CD8 or nudeltaT/CD3 between them. Tubular expression of HLA DR was, however, present only in 4 cases of chronic rejection. In conclusion, T lymphocytes were predominant regardless of diagnosis or disease activity. T lymphocyte subset did not give any suggestion as to the diagnosis or disease activity in chronic rejection. Furthermore nudelta T cells had only limited value. Lymphocytic subsets in peripheral blood would not be predictors of tissue destruction in chronic rejection. 相似文献
75.
Background: The sudden infant death syndrome (SIDS) is still the main cause of postneonatal infant death. However, the causes and mechanisms of SIDS have never been completely elucidated. Catecholamines, via α2-adrenergic receptor (α2-AR) interactions, are known to influence brainstem autonomic and respiratory activity. Aims: To examine the catecholaminergic system abnormalities in SIDS victims, we investigated the alterations of α2-AR subtypes. Subjects and methods: We examined the developmental changes of α2-AR subtypes in the brainstem, especially in cardiorespiratory nuclei, in 21 SIDS victims and 17 age-matched controls by means of immunohistochemical methods. For statistical analysis, the χ2-test or Fisher’s exact probability test was performed. Results: There was a significant decrease in α2A-AR immunoreactivity in the solitary nucleus and ventrolateral medulla (VLM) in the medulla oblongata in SIDS victims compared with in control cases, but there were no significant differences of the α2B and α2C-AR immunoreactivity in the brainstem between SIDS victims and controls. Conclusion: α2A-AR immunoreactivity was selectively decreased in the solitary nucleus and VLM in the medulla oblongata in SIDS victims, so there was no possibility that it was secondary to chronic hypoxia or repeated ischemia. It may be related to some impairment of the cardiorespiratory neuronal system. Therefore, SIDS victims may be vulnerable to asphyxia, hypoxia, and/or hypercapnia, and fail to exhibit brainstem responses. 相似文献
76.
Jeong HJ Sung SH Hong SW Moon JI Kim SI Kim YS Park K 《Virchows Archiv : an international journal of pathology》2000,437(1):69-73
The distribution pattern of extracellular matrix (ECM) components in transplant glomerulopathy was studied in relation to
light microscopic features, actin expression of mesangial cells, and intraglomerular inflammatory cells. Nine cases of mild
(group I) and nine cases of severe (group II) transplant glomerulopathy were stained with antisera against fibronectin (FN),
tenascin (TN), collagen types III and IV, smooth muscle actin, CD45RO, CD68, and Ki-67 antigen. The composition of ECM was
similar in the two groups. The expanded mesangium was diffusely stained by type-IV collagen, FN and TN, and focally and weakly
stained by type-III collagen and smooth muscle actin. Type-IV collagen was linearly stained along the capillary walls, imparting
a double-contour feature, whereas FN and TN showed granular staining along the capillary walls. CD68 positive cells were increased
in severe transplant glomerulopathy, but this increase was not related to ECM deposition. These findings suggest that increased
glomerular deposition of normal and abnormal ECM components participate in the evolution of transplant glomerulopathy.
Received: 5 October 1999 / Accepted: 17 January 2000 相似文献
77.
Hee Jeong Han Sina Labbaf Jessica L. Borelli Nikil Dutt Amir M. Rahmani 《Journal of medical engineering & technology》2020,44(4):177-189
AbstractMonitoring people’s stress levels has become an essential part of behavioural studies for physical and mental illnesses conducted within the biopsychosocial framework. There have been several stress assessment studies in laboratory-based controlled settings. However, the results of these studies do not always translate effectively to an everyday context. The current state of wearable sensor technology allows us to develop systems measuring the physiological signals reflecting stress 24/7 while capturing the context. In this paper, we present a stress monitoring system that provides objective daily stress measurements in everyday settings based on three physiological signals: electrocardiogram (ECG), photoplethysmogram (PPG), and galvanic skin response (GSR) using Shimmer3 ECG, Shimmer3 GSR+, and Empatica E4 wearable sensors. We perform controlled stress assessment experiments on 17 participants in which we successfully detect stress with a 94.55% accuracy for 10-fold cross-validation and an 85.71% accuracy for subject-wise cross-validation. In everyday settings, the system assesses stress with an 81.82% accuracy. We also examine whether motion artefacts affect stress assessment and filter the low-confidence readings to minimise false alarms. 相似文献
78.
Yong D Lim JG Choi JR Park Q Yang CH Choi SH Jeong HJ Song KS 《Yonsei medical journal》2000,41(1):136-139
Klinefelter syndrome (KS) is often associated with various neoplasms, especially germ cell tumors. Mediastinum is the most favored site of extragonadal germ cell tumors with KS, which is somewhat different from those without KS. The retroperitoneal germ cell tumor in KS is very rare. A five-month-old boy with an abdominal mass was found to have a retroperitoneal tumor. After surgical removal, he was diagnosed to have mature cystic teratoma. Cytogenetic study of his peripheral lymphocytes revealed that his karyotype was consistent with KS. This case suggests that patients with KS might be at risk of having germ cell tumors in sites other than mediastinum. It also suggests that all cases with these tumors should be screened for the presence of karyotypic abnormalities, and it might help to assess the exact correlation between germ cell tumors and KS, and to treat them accordingly. 相似文献
79.
Yuri A. Koryak 《Experimental physiology》2002,87(1):101-111
The effects of 7 days of "dry" water immersion were investigated in six subjects. Changes in the contraction properties were studied in the triceps surae muscle. After immersion, the maximal voluntary contraction (MVC) was reduced by 18.9 % (P < 0.01), and the electrically evoked (150 impulses s(-1)) maximal tension during tetanic contraction (P(o)) was reduced by 8.2 % (P > 0.05). The difference between P(o) and MVC expressed as a percentage of P(o) and referred to as force deficiency was also calculated. The force deficiency increased by 44.1 % (P < 0.001) after immersion. The decrease in P(o) was associated with increased maximal rates of tension development (7.2 %) and relaxation. The twitch time-to-peak was not significantly changed, and half-relaxation and total contraction time were decreased by 5.3 % and 2.8 %, respectively, but the twitch tension (P(t)) was not significantly changed and the P(t)/P(o) ratio was decreased by 8.7 %. The 60 s intermittent contractions (50 impulses s(-1)) decreased tetanic force to 57 % (P < 0.05) of initial values, but force reduction was not significantly different in the two fatigue-inducing tests: fatigue index (the mean loss of force of the last five contractions, expressed as a percentage of the mean value of the first five contractions) was 36.2 +/- 5.4 % vs. 38.6 +/- 2.8 %, respectively (P > 0.05). While identical force reduction was present in the two fatigue-inducing tests, it would appear that concomitant electrical failure was considerably different. Comparison of the electrical and mechanical alterations recorded during voluntary contractions, and in contractions evoked by electrical stimulation of the motor nerve, suggests that immersion not only modifies the peripheral processes associated with contraction, but also changes central and/or neural command of the contraction. At peripheral sites, it is proposed that the intracellular processes of contraction play a role in the contractile impairment recorded during immersion. 相似文献
80.
Expression of cell cycle regulators during smooth muscle cell proliferation after balloon catheter injury of rat artery 总被引:3,自引:0,他引:3
Chung JK Lee T Jung IM Kim YK Min SK Suh JW Kim SJ 《Journal of Korean medical science》2004,19(3):327-332
Intimal hyperplasia is defined as the abnormal migration and proliferation of vascular smooth muscle cells (VSMCs) with deposition of extracellular matrix. However, the cell cycle regulatory mechanisms of injury-induced VSMC proliferation are largely unknown. To examine the expression kinetics of cell cycle regulatory factors which is known to be worked positively or negatively, we used rat balloon injury model. Marked induction of proliferating cell nuclear antigen (PCNA), G1/S cyclin-dependent kinase (cdk2), and its regulatory subunit (cyclin E) occurred between 1 and 3 days after balloon arterial injury, and this was sustained for up to 7 days and then declined. However, the induction of the negative regulators, p21 and p27, occurred between 3 and 5 days of injury, peaked after 7 and 14 days and was then sustained. VSMC proliferation after balloon catheter injury of the rat iliac artery is associated with coordinated expression of positive (cdk2, cyclin E and PCNA) and negative (p21, p27) regulators. Cell cycle regulators such as cdk2, cyclin E, p21, p27 may be suitable targets for the control of intimal hyperplasia. 相似文献