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71.
72.
Uirich J. Knappe Dieter K. Lüdecke Maximilian J. A. Puchner Wolfgang Saeger Hans-D. Herrmann 《Endocrine pathology》1991,2(4):200-209
Tissue from 23 pituitary adenomas causing Cushing’s disease was implanted subcutaneously into 159 NuNu/NMRi mice, resected
after 21 or 35 days, and evaluated histologically and immunohistochemically. After 21 days, 74.3% of the grafts survived,
59% having less than 30% necrotic adenoma cells. After 35 days, 45% of the adenoma fragments survived, 37% having less than
30% necrotic adenoma cells. The preservation of the grafts was essentially dependent on the grade of vascularization accomplished
by migration of the host’s capillaries. As assessed by adrenal weight and histologically, biological activity of the transplants
could not be detected. Histologically, the grafts maintained the features of their primary tumors, and adrenocorticotropic
hormone (ACTH) could be visualized immunohistologically.Seventeen mice with subsequently proved preserved adenoma tissue received
an intravenous injection of 12.5 μCi125l-corticotropin-releasing hormone (CRH) and light microscopy-autoradiography was performed. Specific labeling, as verified
by positive and negative controls, was exhibited by 1 1 of 15 transplants originating from 3 highly differentiated ACTH cell
adenomas. Four did not label clearly positive. Two grafts of an undifferentiated mucoid cell pituitary adenoma did not show
any labeling.The nude mouse model is a useful tool for the study of ACTH-producing pituitary adenomas in vivo. Highly differentiated
ACTH cell adenomas can be labeled with radioactive CRH in vivo. 相似文献
73.
George J Barshack I Keren P Gazit A Levitzki A Keren G Roth A 《Experimental and molecular pathology》2005,78(3):233-238
BACKGROUND: Inflammation has been shown to play an important role in promoting the response to arterial injury and proinflammatory cytokines, such as tumor necrosis factor (TNF) alpha, are candidate mediators. AG-556 is a tyrosine kinase inhibitor proven to be effective in a model of multiple sclerosis-like syndrome in mice due to its immunomodulating effect. In the current study, we investigated the effect of the tyrphostin AG-556 on neointimal thickening and cytokine profile in a model of arterial injury in the mouse. METHODS: Injury was induced by external cuff placement on the left femoral artery of wild-type C57BL/6 mice. AG-556 dissolved in DMSO was injected intraperitoneally daily to the injured mice in a dosage of 2 mg/mouse. Control mice received DMSO injections. Histological analysis was carried out to assess neointimal formation. Splenocytes were cultured in the absence and presence of a mitogen for evaluation of thymidine incorporation and cytokine production. RESULTS: AG-556 treatment significantly attenuated intimal thickening (43,000+/-17,000 microm2; n=11) when compared to DMSO administration (286,000+/-127,000 microm2; n=10; P<0.05). Basal interferon-gamma production by splenocytes from AG-556-treated mice was increased by approximately 20-fold in comparison with levels in DMSO-treated animals, whereas Con-A induced secretion of the cytokine was similar between both groups. Levels of TNF-alpha, IL-4 and IL-10 in the culture supernatant from treated and non-treated animals did not differ significantly. CONCLUSION: The tyrosine kinase inhibitor AG-556 may have a role in the reduction of intimal thickening. The effect could be mediated via an immune modulating effect involving a significant increase in the smooth muscle cell inhibitory cytokine IFN-gamma. 相似文献
74.
Montero R Serrano L Dávila V Segura Y Arrieta A Fuentes R Abad I Valencia L Sierra P Camacho R 《Environmental and molecular mutagenesis》2003,42(3):216-222
Micronuclei and other biomarkers were evaluated in oral cells from 11- to 16-year-old girls living in a foster home in the central area of México City. Variables analyzed for possible association with these biomarkers include smoking habits, body mass index, metabolic polymorphisms for NAT1 and GSTM1 and whether the cells were obtained from the cheek or pharynx. The results indicated that individuals having the NAT1*10 homozygous genotype showed a significant increase in chromatin buds and binucleated cells. When the damage in the cheek was compared with damage in the pharynx, a significant increase in micronuclei and binucleated cells was found for the latter tissue in all the individuals analyzed. 相似文献
75.
76.
AIMS: To investigate the serum creatine kinase isoenzyme pattern, specific biochemical markers of bone metabolism, and cytokines in a Chinese family with osteopetrosis, and correlate abnormalities with the pathophysiology of this condition. METHODS: A Chinese female baby was diagnosed with malignant infantile osteopetrosis at the age of 3 weeks by clinical history and biochemical investigations. We studied the laboratory and radiological manifestations of this index case and her family members. RESULTS: Serum CK-BB fraction of our index patient was elevated to 18.0% (normal 1.6-7.6%). Her biochemical markers of bone resorption including serum C-terminal telopeptide concentration and urine N-terminal telopeptide to creatinine ratio were decreased to 0.54 microg/L (normal 0.72-1.56 microg/L) and 159 x 10(-6) (normal 372-900 x 10(-6)), respectively. Serum cytokines including soluble receptor activator of nuclear factor kappa-B ligand (sRANKL) concentration was suppressed to 0.11 pmol/L (normal 0.23-0.82 pmol/L) and osteoprotegerin (OPG) concentration was 4.9 pmol/L (normal 2.8-4.9 pmol/L), resulting in an elevated OPG to sRANKL ratio of 44.5 (normal 3.8-19.4) in favour of bone formation. CONCLUSIONS: If left untreated, this condition is usually fatal within the first year of life. With early diagnosis, management including bone marrow transplantation can be planned ahead and will result in a better survival. 相似文献
77.
Müller AM Hermanns MI Skrzynski C Nesslinger M Müller KM Kirkpatrick CJ 《Experimental and molecular pathology》2002,72(3):221-229
EC culture models are essential to study pathological alterations of endothelial cells (ECs) in pulmonary vascular diseases under standardized conditions. Nevertheless, little is known about the spectrum of alterations of vessel-specific endothelial phenotypes in monolayer cultures. For the comparative study of endothelial markers in vivo and in vitro we investigated immunohistochemically the expression of PECAM-1, vWf, and CD34 by pulmonary ECs in vivo and in stimulated/unstimulated human umbilical vein endothelial cells (HU-VEC) and human pulmonary microvascular endothelial cells (HPMEC). In vivo, vessel type-specific expression patterns were found for vWf and CD34, while PECAM-1 was homogeneously and strongly expressed. While all HUVEC showed a marked vWf staining, about two-thirds of HPMEC exhibited a strong and the rest a moderate vWf staining. In both in vitro models all ECs were clearly PECAM-1-positive. However, only about 20% of the HUVEC and HPMEC were CD34-positive. Our results demonstrate the reduced expression of vessel type-specific endothelial phenotypes by endothelial monolayer cultures, stressing the need to improve culture conditions as well as develop cocultures and three-dimensional culture models. Moreover, the need for endothelial markers specific for single microvascular type ECs becomes obvious in order to establish cultures consisting of only one microvascular ECs subpopulation. 相似文献
78.
Rapid diagnosis of extrapulmonary tuberculosis by PCR: impact of sample preparation and DNA extraction 总被引:6,自引:0,他引:6
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Honoré-Bouakline S Vincensini JP Giacuzzo V Lagrange PH Herrmann JL 《Journal of clinical microbiology》2003,41(6):2323-2329
In cases of suspected extrapulmonary tuberculosis, rapid and accurate laboratory diagnosis is of prime importance, since traditional techniques of detecting acid-fast bacilli have limitations. The major difficulty with mycobacteria is achieving optimal cell lysis. Buffers used in commercial kits do not allow this complete lysis in a number of clinical specimens. A comparison of two sample preparation methods, pretreatment with proteinase K (PK-Roche) and complete DNA purification (cetyltrimethylammonium bromide [CTAB]-Roche), was conducted on 144 extrapulmonary specimens collected from 120 patients to evaluate the impact on the Cobas-Amplicor method. Thirty patients were diagnosed with tuberculosis, with 15 patients culture positive for Mycobacterium tuberculosis. Amplification and detection of the amplicons were impaired by a high number of inhibitory specimens (39 to 52%). CTAB-Roche allowed the detection of more culture-positive specimens by PCR than PK-Roche. Comparison with the final diagnoses of tuberculosis confirmed that CTAB-Roche produced the best sensitivity (53.8%) compared to culture (43.3%), PK-Roche (16%), and smear (13%). However, the specificity of the PCR assay with CTAB-Roche-extracted material was always lower (78.8%) than those with culture (100%) and PK-Roche (96.5%). False-positive specimens were lung biopsy material, lymph node biopsy material and aspirate, or bone marrow aspirate, mainly from immunocompromised patients. Despite the efficiency of complete DNA extraction for the rapid diagnosis by PCR of extrapulmonary tuberculosis, the false-positive results challenge our understanding of PCR results. 相似文献
79.
Individual differences in cognitive reappraisal: experiential and physiological responses to an anger provocation. 总被引:2,自引:0,他引:2
Iris B Mauss Crystal L Cook Jennifer Y J Cheng James J Gross 《International journal of psychophysiology》2007,66(2):116-124
Effective emotion regulation is widely seen as vital for healthy adaptation. There remains considerable uncertainty, however, as to what constitutes effective emotion regulation. One promising emotion regulation strategy is cognitive reappraisal, which involves reframing emotional events so as to decrease their emotional impact. This strategy is useful because it seems to enable individuals to down-regulate negative feelings without the physiological costs that are associated with other forms of emotion regulation. It remains unknown, however, whether individual differences in the use of reappraisal are associated with experiential and physiological responses to anger-inducing situations. To examine this question, individuals either high or low in reappraisal were made angry in the laboratory while emotion experience and cardiovascular responses were assessed. Results indicated that compared to low reappraisers, high reappraisers had a more adaptive profile of emotion experience and cardiovascular responding. Specifically, across baseline and provocation periods, high reappraisers reported less anger, less negative emotion, and more positive emotion, showed greater cardiac output and ventricular contractility, and lesser total peripheral resistance. These findings suggest that reappraisers are successful at down-regulating negative emotions, even in the context of a potent negative emotion such as anger. 相似文献
80.
Roberto Della Bruna Iris Bernhard Bernhard Gess Karin Schricker Armin Kurtz 《Pflügers Archiv : European journal of physiology》1995,430(2):265-272
This study aimed to investigate the inter-relation between the angiotensin II (ANG II) AT1 receptor and renin gene expression in rat kidneys. To this end, renin mRNA levels and mRNA levels for AT1a and AT1b were assayed by RNase protection in the kidneys of normal rats, in animals treated with the AT1 antagonist losartan and in rats bearing 0.2-mm left renal artery clips for 2 days. In normal rats, we found a negative correlation between renin mRNA levels and AT1a receptor mRNA levels. Losartan led to a fourfold increase in renin mRNA levels without changing AT1 receptor mRNA levels. Unilateral renal artery clipping increased renin mRNA levels fourfold in the clipped kidney and suppressed renin mRNA levels in the contralateral kidneys. AT1 receptor mRNA levels were not changed in the contralateral intact kidneys, but were significantly decreased by 15–25% in the clipped kidneys. Renin mRNA levels were inversely correlated to AT1a mRNA levels in the clipped, but not in the contralateral, kidneys. Our findings suggest that the systemic activity of the renin angiotensin system has no regulatory influence on renal AT1 receptor gene expression. Renin mRNA levels in normal and in clipped kidneys appear to be negatively determined by the level of AT1a receptor gene expression. Thus modulation of AT1a receptor gene expression could be a pathway for indirect modulation of renin gene expression by ANG II. This conclusion is in agreement with the observation that AT1 receptor antagonists are powerful stimulators of the renin system. 相似文献