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101.
102.
Lefebvre H Duparc C Chartrel N Jegou S Pellerin A Laquerriere A Ivell R Vaudry H Kuhn JM 《The Journal of clinical endocrinology and metabolism》2003,88(7):3035-3042
Adrenochromaffin cells have been shown to physiologically synthesize and secrete ACTH. We have thus hypothesized that excessive intraadrenal ACTH production may be involved in the pathogenesis of primary adrenal Cushing's syndrome. In this report we describe a case of Cushing's syndrome due to bilateral adrenocortical macronodular hyperplasia associated with suppression of plasma ACTH levels. HPLC analysis of adrenal tissue extracts revealed the presence of a peptide coeluting with bioactive ACTH. Immunohistochemical studies showed that ACTH immunoreactivity was detectable in a subpopulation of steroidogenic cells, but not in chromaffin cells. ACTH-positive cells were also labeled by antibodies against relaxin-like factor, a marker of Leydig cells. The presence of ACTH in the hyperplastic tissue resulted from local expression of the gene encoding the ACTH precursor proopiomelanocortin. Finally, hyperplasia fragments, contrary to normal adrenal cortex explants, appeared to release in vitro measurable amounts of ACTH. In conclusion, this observation shows that Cushing's syndromes associated with suppressed plasma ACTH levels may be dependent upon ACTH produced within adrenocortical tissue. The term ACTH-independent used to designate primary adrenal Cushing's syndrome may therefore be inappropriate in some cases of bilateral macronodular adrenal hyperplasia with hypercortisolism and undetectable plasma ACTH levels. 相似文献
103.
Asymmetric lateral mobility of phospholipids in the human erythrocyte membrane. 总被引:4,自引:2,他引:4 下载免费PDF全文
G Morrot S Cribier P F Devaux D Geldwerth J Davoust J F Bureau P Fellmann P Herve B Frilley 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(18):6863-6867
The fluorescent phospholipid 1-acyl-2-[12-(7-nitrobenz-2-oxa-1,3-diazol-4- yl)aminododecanoyl]phosphatidylcholine (NBD-phosphatidylcholine) and the corresponding aminophospholipid derivatives (NBD-phosphatidylethanolamine and NBD-phosphatidylserine) were introduced in the human erythrocyte membrane by a nonspecific phospholipid exchange protein purified from corn. The lateral mobility of the fluorescent phospholipids was measured by using an extension of the classical photobleaching recovery technique that takes advantage of a modulated fringe pattern and provides a high sensitivity. In intact erythrocytes and in ghosts resealed in the presence of ATP, the fluorescence-contrast curves after photobleaching decayed biexponentially corresponding to two lateral diffusion constants. With NBD-phosphatidylcholine, the majority of the signal corresponded to a "slow" component (1.08 X 10(-9) cm2/sec at 20 degrees C), whereas with the amino derivatives the majority of the signal corresponded to a "fast" component (5.14 X 10(-9) cm2/sec at 20 degrees C). If the ghosts were resealed without ATP, the fast component of the aminophospholipids disappeared. We interpret these results as follows: (i) Provided the cells or the ghosts contain ATP, the three fluorescent phospholipids distribute spontaneously between inner and outer leaflets as endogenous phospholipids, namely NBD-phosphatidylcholine is located in the outer leaflet, while both aminophospholipids are preferentially located in the inner leaflet. (ii) The viscosity of the inner leaflet of human erythrocyte membranes is lower than that of the outer leaflet. 相似文献
104.
Lopes NH Vasudevan SS Gregg D Selvakumar B Pagano PJ Kovacic H Goldschmidt-Clermont PJ 《Circulation research》2002,91(9):798-805
Under ischemic conditions, the vessel wall recruits inflammatory cells. Human aortic endothelial cells (HAECs) exposed to hypoxia followed by reoxygenation produce monocyte chemoattractant protein-1 (MCP-1); however, most experiments have been performed in the presence of nutrient deprivation (ND). We hypothesized that ND rather than hypoxia mediates endothelial MCP-1 production during ischemia, and that the small GTP-binding protein Rac1 and reactive oxygen species (ROS) are involved in this process. ND was generated by shifting HAECs from 10% to 1% FBS. Superoxide production by HAECs was increased 6 to 24 hours after ND, peaking at 18 hours. MCP-1 production was increased over a similar time frame, but peaked later at 24 hours. These effects were blocked by treatment with antioxidants such as superoxide dismutase mimetic and N-acetylcysteine (NAC), or NADPH oxidase inhibitors, DPI and gp91ds-tat. Superoxide and MCP-1 production were enhanced by RacV12 (constitutively active) in the absence of ND, and were inhibited by RacN17 (dominant-negative) adenoviral transduction under ND, suggesting that the small G-protein Rac1 is required. In conclusion, ND, an important component of ischemia, is sufficient to induce MCP-1 production by HAECs, and such production requires a functional Rac1, redox-dependent pathway. 相似文献
105.
C Herve A M Duval J Malak A Meguira P Brun 《Journal of the American College of Cardiology》1990,15(7):1587-1593
M-mode echocardiography reveals an abrupt change between early and late left ventricular posterior wall kinetics during relaxation. No attempt has been previously made to relate this wall kinetic change and transmitral flow rate. In 25 normal subjects, 14 patients with dilated cardiomyopathy (Group 1) and 17 patients with hypertrophic cardiomyopathy (Group 2), M-mode echocardiographic studies were performed on the posterior wall and mitral valve. Transient values of mitral orifice area were calculated and transmitral flow velocities were recorded: area and velocity data yielded transmitral flow rates. Time intervals were determined from mitral opening to peak early area, velocity and flow rate and to posterior wall slope change. An additional group included five patients with a mitral prosthesis. The posterior wall slope change was present when part of the myocardial structures were almost akinetic or when mitral chordae tendineae were absent; slope change appeared as a regional phenomenon in the free wall. In the normal subjects, close values were found for the four time intervals. In the patients with dilated and hypertrophic cardiomyopathy, peak early velocity (95.7 +/- 16.7 and 146.2 +/- 31.4 ms, respectively), peak flow rate (84.7 +/- 18.2 and 137.4 +/- 29.5 ms) and time to slope change (91.4 +/- 18.6 and 133.6 +/- 32.7 ms) were significantly delayed (p less than 0.001) in comparison with peak area (56.6 +/- 9.5 and 84.3 +/- 22.5 ms). Slope change does not indicate the end of the early filling phase but, rather, its transition from acceleration to deceleration. Time to peak velocity or time to peak filling rate must be considered in a relaxation analysis. 相似文献
106.
Limat S Woronoff-Lemsi MC Deconinck E Racadot E Jacquet M Herve P Cahn JY 《Bone marrow transplantation》2000,25(9):997-1002
Intensive high-dose chemotherapy with peripheral blood progenitor cell (PBPC) transplantation is a common strategy for aggressive non-Hodgkin's lymphomas (NHL). A retrospective cost-effectiveness analysis of CD34+ cell dose was carried out. Between 1994 and 1998, 28 patients were included. Efficacy was measured by the length of aplasia. Data collection concerned the period from graft day until discharge from hospital, and the post-graft period until graft day +100. Patients transplanted using a cell dose greater than 5 x 106/kg were found to have a faster hematological recovery. Average length of post-graft hospitalization was shorter and fewer blood products were required for patients with more than 5 x 106/kg CD34+ cells transplanted. Hospitalization was the major cost driver. A large reduction in procedure cost was obtained with a CD34+ cell count higher than 5 x 106/kg (-US$2740, -11%). This difference was directly related to hospitalization (-US$860) and platelet units transfused (-US$1,340). A sensitivity analysis showed the robustness of results. Our findings indicated that a CD34+ cell dose higher than 5 x 106/kg was more cost-effective than a lower dose in NHL patients. The collection of 5 x 106/kg CD34+ cells appeared necessary to optimize the PBPC procedure. 相似文献
107.
A. Gentric J.P. Herve J. Cledes Y. Pennec J.P. Leroy J. Guiserix P. Simon 《La Revue de médecine interne / fondée ... par la Société nationale francaise de médecine interne》1986,7(5)
The interstitial nephritis associated with sicca syndrome is usually symptomless or responsible for mild renal impairment. The authors report five cases in which renal failure was severe, requiring haemodialysis in two patients. The physiopathological mechanisms and the treatment of intertitial nephritis in sicca syndrome are discussed. Corticosteroids improved renal function in three of these five patients. 相似文献
108.
Loeffler DA Lundy SK Singh KP Gerard HC Hudson AP Boros DL 《The Journal of infectious diseases》2002,185(11):1650-1656
Schistosomiasis mansoni is characterized by hepatic granuloma formation. Endothelial cell activation within these granulomas may contribute to their development and to increased vascularization in the granuloma periphery. The earliest event in granuloma formation is the lodging of schistosome eggs within presinusoidal capillaries. The eggs secrete factors that may activate endothelial cells. This study investigated the effects of Schistosoma mansoni soluble egg antigen (SEA) on angiogenic processes: proliferation, tube formation, and apoptosis of human umbilical vein endothelial cells (HUVECs). HUVECs require serum and growth factors to proliferate in vitro. Proliferation occurred when SEA or live eggs were substituted for growth factors, but not for serum. SEA increased HUVEC tube formation and decreased HUVEC apoptosis after serum and growth factor deprivation. Messenger RNA for vascular endothelial growth factor (VEGF) increased 2-fold in SEA-treated HUVECs. These findings suggest that products secreted by schistosome eggs may promote angiogenesis within hepatic granulomas by up-regulating endothelial cell VEGF. 相似文献
109.
Mild isocapnic hypoxia enhances the bronchial response to methacholine in asthmatic subjects 总被引:3,自引:0,他引:3
A Denjean C Roux P Herve J P Bonniot E Comoy P Duroux C Gaultier 《The American review of respiratory disease》1988,138(4):789-793
We studied the effect of mild isocapnic hypoxia (FIO2 = 15.5%) on lung mechanics, heart rate, circulating plasma catecholamines, and bronchial responsiveness to methacholine in ten asthmatic adults. Hypoxia did not alter lung mechanics (i.e., dynamic pulmonary compliance [CLdyn], pulmonary resistance [RL]) nor did it increase plasma catecholamines, but it significantly increased bronchial responsiveness to aerosolized methacholine, as assessed by the fall in forced expiratory volume in one second (FEV1: 1.2 +/- 0.18 versus 0.9 +/- 0.14 L/s, p less than 0.05), the rise in RL (RL: 19.1 +/- 1.4 versus 8.4 +/- 1 cm H2O/L/s, p less than 0.05), and the steeper slope of the dose-response curve to methacholine. We concluded that the hypoxic characteristic of asthmatic attacks may aggravate airflow obstruction. 相似文献
110.
Jrme Ateudjieu David A Sack Sonia Sonkeng Nafack Shaoming Xiao Ketina Hirma Tchio-Nighie Herve Tchokomeni Landry Beyala Bitaa Paul Ntsekendio Nyibio Etienne Guenou Kedia Mayah Mondung Frank Forex Kiadjieu Dieumo Rosanne Minone Ngome Kelsey N. Murt Malathi Ram Mohammad Ali Amanda K. Debes 《The American journal of tropical medicine and hygiene》2022,107(5):974