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1.
The suppressive effect of hydrocortisone and dexamethasone on salivary cortisol was investigated in a 2-year study of pituitary-adrenal function in a variety of child psychiatric patients and healthy controls. Symptomatology was assessed using the Child Behavioral Checklist (CBCL). Cortisol day profiles were assessed at 2-h intervals from 0800 to 2000 h on three occasions. Dexamethasone and hydrocortisone were administered orally twice at 2000 h, the doses being adjusted for bodyweight according to the standard dexamethasone suppression test. Fifty-one patients, including patients with dysthymia, oppositional defiant disorder, pervasive developmental disorder, and attention deficit hyperactivity disorder, and ten age and sex matched controls participated. Basal cortisol levels in patients were generally lower than in controls. Both dexamethasone and hydrocortisone were effective in suppressing salivary cortisol, although dexamethasone was somewhat more potent and its effect lasted longer. Hyporesponsiveness to hydrocortisone, but not to dexamethasone, distinguished patients with dysthymia and oppositional defiant disorder from controls. Responsiveness to hydrocortisone was correlated with the symptom clusters social problems and anxious/depressed. The data support the idea that there exist syndrome aspecific disturbances in feedback activity beyond the level of the pituitary, i.e. at the hypothalamic level, at an early age. From this perspective, hydrocortisone suppression is a useful tool for studying pituitary-adrenal function in children. Behavioral correlates of these disturbances of pituitary-adrenal function should be determined.  相似文献   

2.
Establishment of an osteocyte-like cell line, MLO-Y4   总被引:1,自引:0,他引:1  
Although osteocytes are the most abundant cells in bone, their functional role remains unclear. In part, this is due to lack of availability of osteocyte cell lines which can be studied in vitro. Since others have shown that cell lines can be readily developed from transgenic mice in which the SV40 large T-antigen oncogene is expressed under the control of a promoter which targets the cells of interest, we used this approach to develop an osteocyte cell line. We chose as a promoter osteocalcin, whose expression is essentially limited to bone cells and which is expressed more abundantly in osteocytes than in osteoblasts. From these transgenic mice, we isolated cells from the long bones using sequential collagenase digestion and maintained these cells on collagen-coated surfaces which are optimal for osteocyte maintenance and growth. We describe here the properties of a cell line cloned from these cultures, called MLO-Y4 (for murine long bone osteocyte Y4). The properties of MLO-Y4 cells are very similar to primary osteocytes. Like primary osteocytes and unlike primary osteoblasts, the cell line produces large amounts of osteocalcin but low amounts of alkaline phosphatase. The cells produce extensive, complex dendritic processes and are positive for T-antigen, for osteopontin, for the neural antigen CD44, and for connexin 43, a protein found in gap junctions. This cell line also produces very small amounts of type I collagen mRNA compared with primary osteoblasts. MLO-Y4 cells lack detectable mRNA for osteoblast-specific factor 2, which appears to be a positive marker for osteoblasts but may be a negative marker for osteocytes. This newly established cell line should prove useful for studying the effects of mechanical stress on osteocyte function and for determining the means whereby osteocytes communicate with other bone cells such as osteoblasts and osteoclasts.  相似文献   

3.
We have earlier shown that enterocyte mitochondria contain a phospholipase D (PLD) activity which can be stimulated by oxygen free radicals, divalent cations and polyamines. The functional significance of this enzyme in mitochondria is not known but it can be investigated using selective inhibitors. In the present study, mitochondrial PLD was activated by exposure to oxidants (X+XO or menadione), calcium or polyamines and the effect of antimalarial drugs, chloroquine, amodiaquin and primaquine on PLD activity was studied. Chloroquine and amodiaquine inhibited Ca2+ stimulated PLD activity in dose dependent manner whereas these drugs had no significant effect on PLD activated by oxidants or polyamines. Increasing the calcium concentration relieved the PLD inhibition by these drugs. Primaquine did not have any effect on calcium stimulated PLD activity whereas it slightly activated the enzyme. These results indicate that chloroquine and amodiaquine may bind with calcium making it unavailable for PLD activation.  相似文献   

4.
The obtention of a diploid cell line from human lung of great concern for the virological diagnosis and research is reported. Certain aspects about its application and characterization are discussed.  相似文献   

5.
We have established an erythropoietin-dependent human leukemia cell line, AS-E2, from a patient with acute myeloid leukemia. These cells have many characteristics of late erythroid progenitor cells, they are positive for CD36, Glycophorin A, and CD71 but negative for CD41, and positive for benzidine and PAS staining. These cells express GATA-1 and have low affinity erythropoietin (EPO) receptor on their surface. Interestingly, AS-E2 cells are strictly dependent on EPO for their growth and survival; other cytokines including GM-CSF, stem cell factor, or IL-3 cannot support the growth of this cell line. These features are similar to late erythroid lineage cells, like normal BFU-E or CFU-E, and we have demonstrated that EPO stimulation induces the tyrosine phosphorylation of several proteins in AS-E2 cells including the EPO receptor and JAK2 kinase. This new cell line is a useful reagent to study biological and molecular events during the late stages of erythropoiesis, and to understand transforming events in human erythroid cells.  相似文献   

6.
A new saponin named gypentonoside has been isolated from Gynostemma pentaphylum (Thunb) Makino, C54H88O21, mp 272-274 degrees C. Its structure was established on the basis of chemical and spectroscopic (IR, FAB-MS, UV, 1H-NMR, 13C-NMR, 2D-NMR) analyses.  相似文献   

7.
Hürthle cell carcinomas (HCC) of the thyroid are a variant of follicular thyroid tumors. In contrast to follicular thyroid carcinoma, HCC rarely take up radioiodine and frequently metastasize to the lymph nodes. Histologically they are indistinguishable from Hürthle cell adenomas except for evidence of invasion and metastasis. How these carcinomas develop and why they behave differently than other follicular tumors is not known. Although some differentiated thyroid cancer cell lines exist, none are from Hürthle cell tumors. We have established a well-differentiated thyroid cancer cell line from a metastasis of a HCC, designated XTC.UC1. In vitro, XTC cells display epitheloid morphology, grow with a population doubling time of 4.3 +/- 0.3 days, migrate, and invade through reconstituted basement membranes. The cells are immunoreactive for and release thyroglobulin, respond to thyrotropin (TSH) with increase of intracellular cyclic adenosine monophosphate (cAMP), proliferation, and invasion of reconstituted basement membrane, thus exhibiting characteristics of well-differentiated thyroid carcinoma. In vivo, xenografted XTC cells grow with a doubling time of 9.8 +/- 0.8 days. Tumors spontaneously metastasize to the lymph nodes and less frequently to the lungs and the liver. The cells retained their differentiated function in vivo as assessed by human thyroglobulin (hTG) secretion and immunohistochemistry. This is a first report of the establishment of a unique, highly differentiated thyroid carcinoma cell line derived from an HCC. Based on the ability to invade through reconstituted basement membrane in vitro and the potential to metastasize in vivo, this cell line may provide a unique model to study invasion and metastazation of well-differentiated thyroid cancer.  相似文献   

8.
A new cell line with megakaryoblastic features, designated UoC-M1, was established from the malignant cells of a 68-year-old patient with acute myeloid leukemia. The patient's leukemic cells reacted with alpha-naphthyl acetate esterase and acid phosphatase and expressed CD7, CD24, CD34, CD38, CD45, HLA-DR and CD61. Cytogenetic analysis of the patient's malignant cells (and of the UoC-M1 cells) showed a human, male hypodiploid karyotype with many chromosome rearrangements and marker chromosomes. Spectral karyotyping (SKY) analysis complemented the G-banded karyotyping and clarified several chromosomal translocations and identified the marker chromosomes. Fluorescence in situ hybridization (FISH) and SKY analysis demonstrated that one marker chromosome contained three segments of chromosome 9 interspersed with three segments of chromosome 11, as well as a portion of chromosome 19. FISH analysis with a probe for MLL revealed that the UoC-M1 cells contained four copies of the MLL gene. Southern blot analysis determined that the MLL gene had a germline profile while Northern and Western analyses showed that the MLL mRNAs and protein were of the appropriate sizes. This is the first report of amplification of the MLL gene which may be an additional mechanism of leukemogenesis or disease progression.  相似文献   

9.
A canine lymphoma cell line (CL-1) was established in culture from tumor cells found in the pleural fluid of a 7-year old female Japanese terrier with thymic form lymphoma. The CL-1 cells were positive for CD45 and MHC class II and negative for CD4, CD5, CD8, Thy-1 and B-cell specific antigen and surface immunoglobulin. The CL-1 cells had a rearranged T-cell receptor beta-chain gene and a germ-line form immunoglobulin gene, indicating that the CL-1 cells represented a monoclonally expanded population of canine alpha beta T-cell lineage.  相似文献   

10.
The aim of this study was to try establishing mouse ES cell lines from the early developmental stage. Fifty-two uncompacted 8-cell stage embryos were dissociated and single blastomeres were seeded on primary embryonic fibroblasts in DMEM/F12 completed with 10% foetal calf serum, 10% new born calf serum. 10(-4) M beta-mercaptoethanol. After approximately 5 days of culture, multiple cell clones exhibiting stem cell morphology grew out and were dissociated. One cell line was established (MSB1) and characterised. The karyotype and the G-banding revealed a male diploid cell line. MSB1 cells were injected into syngenic mice and produced teratocarcinomas. Detailed histological examination of the tumours showed a great variety of cell types including representatives of all three primary germ layers. Several nests of undifferentiated stem cells were also present. Microinjections of MSB1 cells into 52 blastocysts produced 2 chimeras, 1 male and 1 female. These results demonstrate that a highly pluripotents ES cell line can be derived from 8-cell stage mouse embryos. However, the male chimera appeared sterile. More experiments would thus be necessary to prove that the cell line obtained is capable to colonise the germ line.  相似文献   

11.
12.
The high prevalence of cholesterol gallstone disease in hypertriglyceridemic patients may be associated with frequent metabolic defects in cholesterol and bile acid syntheses and in the concomitant formation of bile supersaturated with cholesterol. This study had the two aims: 1) to assess whether the defects as well as the degree of biliary cholesterol supersaturation in patients with hyperlipoproteinemia (HLP) can be estimated by the simultaneous determination of plasma mevalonate (MVL) and 7alpha-hydroxy-4-cholesten-3-one (C4); and 2) to assess the possible application of an estimated cholesterol saturation index ([CSI]E) as a means of evaluating the clinical effects of simvastatin on biliary lipid composition. Biliary cholesterol supersaturation was observed in patients with both IIa and IV HLP types. Consistent with the high activity and steady-state messenger RNA level of 3-hydroxy-3 methylglutaryl coenzyme A (HMG-CoA) reductase, plasma MVL was significantly higher in 86 patients with HLP (38 type IIa, 44.1 +/- 2.4 nmol/L and 48 type IV, 56.7 +/- 2.3; P < .01) than in 41 normolipidemic subjects (34.2 +/- 1.5), closely correlating with the molar percentage of cholesterol in bile (r = .61, P = .0001; n = 86). On the other hand, consistent with the high activity and messenger RNA level of cholesterol 7alpha-hydroxylase, plasma C4 was significantly higher in patients with HLP (type IIa, 28.8 +/- 2.3 nmol/L and type IV, 38.3 +/- 2.7; P < .01) than in normolipidemic subjects (17.4 +/- 1.5). Plasma C4 was closely correlated with plasma MVL (r = .40, P = .0001; n = 86), but was inversely correlated with the molar percentage of bile acids in bile (r = .49, P = .0001; n = 86). Assuming that cholesterol supersaturation in patients with HLP may be governed by both an enhanced cholesterol secretion (closely reflected by plasma MVL) and a decreased secretion of bile acids (closely reflected by plasma C4), the multivariate linear regression-analyses revealed that an index defined as estimated CSI ([CSI]E) (%) in patients with HLP was given by the following equation using plasma MVL and C4 (nmol/L): [CSI]E = 1[MVL] + 0.7[C4] + 44.4. Biliary cholesterol supersaturation in patients treated with simvastatin improved in a manner parallel to the time course of decreases in plasma MVL and C4. The [CSI]E before and at the end of treatment were correlated with biliary CSI. These results indicate that defects of hepatic cholesterogenesis, and bile acid synthesis, and the degree of biliary cholesterol supersaturation in patients with HLP can be estimated exactly by the simultaneous determination of plasma MVL and C4; furthermore [CSI]E may be adopted for clinical use as a convenient index of biliary CSI.  相似文献   

13.
Brainstem evoked potentials (BAEPs) were determined in three groups of male prisoners of war (POWs) released from detention camps and a control group. The first group comprised 21 POWs in whom BAEPs were determined 10-60 days after release (group I). The second group comprised 24 POWs in whom BAEPs were determined 6-9 months after release (group II), and the third group comprised 22 POWs in whom BAEPs were determined 12-18 months after release (group III). The control group comprised 32 subjects. The following changes were found in relation to the control group: in group I significantly longer interpeak latencies (IPLs) P1-P3; in group II significantly longer IPLs P1-P3 and P3-P5; and in group III significantly longer IPLs P1-P3. The subjective symptomatology of the POWs and the results of a routine examination indicate subclinical functional changes of the central nervous system, reflecting the dynamics of these changes. It is suggested that the basis of these changes may be a demyelinization intrathecal process, which occurred as a result of immunological changes during prolonged and intensive post-traumatic stress syndrome.  相似文献   

14.
15.
The ultimate goal of this study was to compare the fate of rat testicular germ cells cocultured with mouse Sertoli cells that either do or do not produce rat androgen-binding protein (ABP). As a first step, we stably transfected a rat ABP expression construct into an immortalized mouse Sertoli cell line (TM4), which does not produce ABP when growing on plastic without hormones. The transfection of the pRc/CMV- rat ABP cDNA expression vector containing a neomycin resistance gene was made by either the liposome method (Dotap) or by polyethyleneimine transfection (PEI) into TM4 cell cultures. Neomycin-resistant clones were selected by adding Geneticin to the culture medium for 3 weeks. Analysis of over 25 clones revealed the presence of recombinant rat ABP when cell extracts and culture media were probed with a rabbit polyclonal antibody raised against rat testicular ABP, indicating the translation and secretion of a protein similar to rat testicular ABP. Transfected TM4 cells maintain the secretion of rat ABP for more than 40 days, with immunopositive rat ABP localized within cytoplasmic granules in the Golgi region and along cytoplasmic processes in TM4 transfected with either vector. Electron microscopic study revealed a higher development of cytoplasmic organelles involved in protein secretion.  相似文献   

16.
In the mammalian central nervous system (CNS), multipotential neural stem cells in the neuroepithelium generate the three major types of neural cells, namely, neurons, astrocytes, and oligodendrocytes. To explore the molecular mechanisms underlying proliferation and differentiation of these neural stem cells, we established a cell line named MNS-57 from the embryonic day 12 rat neuroepithelium by introducing the mycer fusion gene, in which c-myc can be conditionally activated by adding oestrogen to the culture medium. MNS-57 cells expressed nestin, vimentin, and the RC1 antigen, which are potential markers for neural stem cells. We show that under particular culture conditions, MNS-57 cells can conditionally generate neurons, astrocytes, and oligodendrocytes in vitro, indicating that they are likely to originate from multipotential neural stem cells. Incubating MNS-57 cells with either oestrogen, which activates mycer, or growth factors such as basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) stimulated their growth, and the combination of oestrogen and bFGF (or EGF) had a synergistically stronger mitogenic effect than the single factors. Furthermore, both c-myc activation and bFGF appeared to be necessary for the differentiation of MNS-57 cells, and only when stimulated by both signals simultaneously, the cells committed to generating multiple neural cell types. Thus, the property of the cell line is unique in that its differentiation into neurons and glia can be conditionally manipulated in vitro in an exogenous signal-dependent manner. We propose that the cell line described here will provide an useful in vitro model to understand genetic and environmental mechanisms that control the generation of neural cell diversity in the CNS.  相似文献   

17.
PURPOSE: The aims of this study were to establish a kinetic means of analyzing the membrane transport of organic cations in renal epithelial cells, and to simultaneously evaluate drug interactions in apical and basolateral membranes. METHODS: Tetraethylammonium (TEA) transport was measured using LLC-PK1 cell monolayers grown on microporous membrane filters. After incubating the cells with unlabeled TEA or other drugs, apical or basolateral medium was changed to that containing labeled TEA, and transcellular transport and cellular accumulation were measured. Clearance from apical medium to cells (CL12), cells to apical medium (CL21), cells to basolateral medium (CL23) and basolateral medium to cells (CL32) were calculated based on a three compartment model. RESULTS: TEA was accumulated progressively in the monolayers from the basolateral side and was transported unidirectionally to the apical side. CL32 was greater than CL12 and CL23 was greater than CL21. Therefore, the rate limiting step of TEA transport from the basolateral to the apical medium was the cell-to-apical step. Co-incubation of TEA with procainamide decreased the transport parameters of TEA, CL12, CL21 and CL32, whereas that with levofloxacin decreased only CL12 and CL21, not affecting the parameters in basolateral membranes. CONCLUSIONS: Using a simple model, we analyzed the transport of organic cation in kidney epithelial cell line, LLC-PK1. This method can be useful for the analysis of cation transport and drug interactions in the apical and basolateral membranes of renal tubules.  相似文献   

18.
Myoepithelial cells exert important paracrine effects on epithelial morphogenesis and mitogenesis through direct cell-cell interactions and through synthesis of a basement membrane extracellular matrix. To study these effects further, this study established the first immortalized human myoepithelial cell line, HMS-1, and transplantable xenograft, HMS-X, from the rare parotid basal cell adenocarcinoma. The cell line exhibited a fully differentiated myoepithelial phenotype and the xenograft exhibited the rare property of accumulating an abundant extracellular matrix composed of both basement membrane and nonbasement membrane components with the latter predominating. With HMS-1 as a feeder layer, dramatic and specific induction of epithelial morphogenesis (spheroid formation) occurred with selected normal epithelial and primary carcinoma target cells. HMS-1 and HMS-X provide distinct advantages over the conventional murine matrices in existence. They will be invaluable in future studies of human tumor-myoepithelial and matrix interactions important for tumor cell growth, invasion, and metastasis.  相似文献   

19.
DSD-1-PG is a chondroitin sulfate proteoglycan with neurite-outgrowth promoting properties expressed during development and upon lesion of neural tissues which has been defined with the specific monoclonal antibody 473HD. Double immunofluorescence studies performed on primary cerebellar cultures document that the proteoglycan is expressed on the surface of immature glial cells and the neural cell line Oli-neu, a model of mouse oligodendrocyte progenitors. Biochemical and immunoprecipitation studies performed with biosynthetically labelled Oli-neu and primary neural cells demonstrated that DSD-1-PG is expressed in vitro as a proteoglycan of 1000 kD apparent Mr with two core glycoproteins of 250 kD and 400 kD. In order to study the regulation of DSD-1-PG expression, an in vitro enzyme-linked immunosorbent assay based on Oli-neu and mAb 473HD was established. TGF-beta1-3 induced up-regulation of the proteoglycan, while various growth factors and cytokines did not significantly affect DSD-1-PG expression in both the supernatant and the extract of the culture monolayer. FACSCAN analysis suggested that the proteoglycan is upregulated on the surface of Oli-neu. Cell substrate adhesion assays revealed that this enhanced expression correlates with a selective reduction of adhesion to laminin, but not fibronectin or merosin, which could specifically be neutralized by antibodies to DSD-1-PG. We conclude that the proteoglycan contributes to the regulation of glial precursor interactions with the extracellular matrix.  相似文献   

20.
Transforming growth factor -beta (TGF-beta) is growth inhibitory to many malignant cells, including prostate cancer cells. The present study reports an unusual observation in that TGF-beta is growth stimulatory to a human prostate cancer cell line, TSU-Pr1. The TSU-Pr1 line is highly aggressive and exhibits a rapid rate of proliferation in culture. These cells underwent further proliferation in response to TGF-beta1. Both type I and II receptors to TGF-beta (TPR-I, TPR-II) are expressed in TSU-Pr1 cells. Activation of a luciferase reporter gene, which contains a TGF-beta response element, confirmed that the TGF-beta receptors in TSU-Pr1 cells were functional. RT-PCR analysis and an ELISA assay determined that TSU-Pr1 cells secreted TGF-beta. In conclusion, TSU-Pr1 cells contain functional TGF-beta receptors but instead of the usual growth inhibition by TGF-beta1, these cells undergo proliferation. The present observation provides a proliferative role of TGF-beta in TSU-Pr1 cells, which may play a part in the aggressive phenotype of these cells and, perhaps other prostate cancer cells.  相似文献   

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