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41.
A possible autocrine role for interleukin-6 in two lymphoma cell lines   总被引:8,自引:1,他引:8  
Interleukin-6 (IL-6) is a growth factor with diverse biologic activity. Originally described as a T-cell product that enhances immunoglobulin (Ig) secretion in antigen-stimulated B cells, it also affects the growth of T cells, plasmacytomas, hybridomas, and hematopoietic stem cells. We report the expression and secretion of IL-6 by two lymphoma cell lines, OCI-LY3 and OCI-LY12. Addition of recombinant IL-6 stimulated their growth, whereas addition of polyclonal anti- recombinant IL-6 (anti-rIL-6) had a marked inhibitory effect on proliferation. These results suggest an autocrine role for IL-6 in the growth of these lymphoma cells in culture.  相似文献   
42.
The DAZLA (DAZ Like Autosomal) gene on human chromosome 3 shares a high degree of homology with the DAZ (Deleted in AZoospermia) gene family on the Y chromosome, a gene family frequently deleted in males with azoospermia or severe oligospermia. The involvement of both DAZ and DAZLA in spermatogenesis is suggested by their testis-specific expression and their homology with a Drosophila male infertility gene, boule. Whereas male infertility resulting from deletion of the DAZ genes on the Y chromosome occurs sporadically, that due to a defective DAZLA gene is expected to be inheritable. The fraction of males with idiopathic azoospermia or oligospermia that harbour mutations in the DAZLA gene remains unknown. As a prerequisite for mutation screening, the genomic structure of the DAZLA gene was elucidated and found to consist of 11 exons spanning 19 kh. The exon/intron boundaries are conserved between DAZ and DAZLA. The 5' end of both genes are hypomethylated in spermatozoa but not in leukocytes or placenta, consistent with the expression pattern of the genes. The genomic structure of DAZLA paves the way for mutation detection in families with autosomal recessive male infertility.   相似文献   
43.
Primary spinal hydatid disease is rare and represents an uncommon but significant manifestation of hydatid disease. We report a case of primary intraspinal extradural hydatid cyst of the thoracic region causing spinal cord compression. The presenting symptoms were mostly atypical and the diagnosis was established preoperatively on the basis of magnetic resonance imaging. The patient underwent surgery resulting in complete recovery and is recurrence-free after 24 months follow-up.  相似文献   
44.
Pairs of sequential perfusion lung scans and pulmonary angiograms obtained in 45 patients were reviewed to investigate the utility of short-term, sequential scintigraphy in the diagnosis of pulmonary embolism (PE). Forty-six sequential scan pairs were reviewed; 13 were ventilation-perfusion (V-P) pairs. Angiograms were obtained within 48 hours of either the first (65%) or second (35%) perfusion scan in each pair. Sequential scintigraphic patterns were classified as showing change (i.e., improvement in defects, new defects), no change, or as being indeterminate. A changing perfusion pattern was associated with a high (20/23) likelihood of PE, but seven of 16 patients with stable perfusion patterns also had PE. The sensitivity of a changing perfusion pattern for PE was 0.74 (20/27) and its specificity was 0.75 (9/12). In two of six patients who had serial V-P studies that showed changing perfusion defects, there were matched changes in regional ventilation and angiograms were negative. The findings suggest that short-term serial perfusion lung scanning may aid the scintigraphic diagnosis of PE in certain circumstances. Serial V-P imaging is needed, however, to maximize diagnostic specificity.  相似文献   
45.
ObjectivesTo describe the quality of reporting and investigation into surgical Never Events in public reports.DesignSemi-quantitative and qualitative review of published Quality Accounts for three years (2011/2–2013/14). Data on Never Events were compared with previously collated Never Events rates. Quality of reported investigations was assessed using the London Protocol.SettingEnglish National Health Service.ParticipantsAll English acute hospital trusts.ResultsQuality Accounts were available for all Trusts for all three years, of which 342 referred to years when a surgical Never Event had occurred. A total of 125 of 342 (37%) accounts failed to report any or all Never Events that had occurred; 13/342 (4%) provided full disclosure; 197 (58%) reported that some investigation had taken place. Of these 197, 61 (31%) were limited in scope; 61 (31%) were categorised as detailed reports. Task and Technology factors were the commonest factor (103/211 (49%)) Identified in investigations, followed by Individual factors (48/211 (23%)). Team and Work environment factors were identified in 29/211 (14%) and 23/211 (11%), respectively. Organisational and Management 5/211 (2%) factors were rarely identified, and the Institutional context was never discussed.ConclusionsReporting of Never Events and their investigations by English NHS Trusts in their Quality Accounts is neither consistently transparent nor adequate. As with clinical error, the true root causes are likely to be organisational rather than individual.  相似文献   
46.
A macrophage-derived inhibitor of early hematopoietic progenitors (colony-forming unit-spleen, CFU-A) called stem cell inhibitor was found to be identical to macrophage inflammatory protein-1 alpha (MIP-1 alpha). We investigated the effect of MIP-1 alpha on the earliest stem cells that sustain long-term hematopoiesis in vivo in a competitive bone marrow repopulation assay. Because long-term reconstituting (LTR) stem cells are normally quiescent, an in vivo model was first developed in which they are triggered to cycle. A first 5-fluorouracil (5-FU) injection was used to eliminate later progenitors, causing the LTR stem cells, which are normally resistant to 5-FU, to enter the cell cycle and become sensitive to a second 5-FU injection administered 5 days later. Human MIP-1 alpha administered from day 0 to 7 was unable to prevent the depletion of the LTR stem cells by the second 5-FU treatment, as observed on day 7 in this model, suggesting that the LTR stem cells were not prevented from being triggered into cycle despite the MIP-1 alpha treatment. However, the MIP-1 alpha protocol used here did substantially decrease the number of more mature hematopoietic progenitors (granulocyte-macrophage colony-forming cells [CFC], burst- forming unit-erythroid, CFCmulti, and preCFCmulti) recovered in the bone marrow shortly after a single 5-FU injection. In vitro, MIP-1 alpha had no inhibitory effect on the ability of these progenitors to form colonies. This study confirms the in vivo inhibitory effect of MIP- 1 alpha on subpopulations of hematopoietic progenitors that are activated in myelodepressed animals. However, MIP-1 alpha had no effect on the long-term reconstituting stem cells in vivo under conditions in which it effectively reduced all later progenitors.  相似文献   
47.
The surface glycoprotein CD36 (GPIV) is known to mediate the adhesion of Plasmodium falciparum malaria-infected red blood cells and to be a receptor for extracellular matrix proteins such as collagen and thrombospondin. The murine monoclonal IgM antibody NL07, which is specific for CD36, has now been shown to also be a potent inhibitor of the adhesion of P falciparum malaria-infected red blood cells to C32 melanoma cells. Treatment of platelets with NL07 monoclonal antibody resulted in rapid degranulation, release of ATP and serotonin, increase in [Ca2+]i, and tyrosine phosphorylation of a substrate protein of 130 kD. In about one-half of the experiments, activation with NL07 resulted in the formation of small aggregates of 10 to 30 platelets, whereas in the other half of the experiments, large aggregates were seen similar to those induced by adenosine diphosphate (ADP) and these large aggregates could be converted to the small aggregates by ATP alpha S or by AP-2 or other antibodies against GPIIb and/or IIIa. Microaggregates of 2 to 5 platelets were seen with Glanzmann's platelets that constitutively lack GPIIb/IIIa. Aggregate formation was not seen with heat-treated serum, in the presence of anti C1q antibodies, or when using C5-, C8-, or C9-deficient human sera. Although activation of platelets with purified complement components results in a slow morphologic change without aggregation, involvement of CD36 results in rapid complement-mediated activation leading to formation of small aggregates that is largely independent of GPIIb/IIIa and that, under certain circumstances, proceeds to the formation of large ADP-dependent aggregates.  相似文献   
48.
Trevisan  M; Yan  XQ; Iscove  NN 《Blood》1996,88(11):4149-4158
This investigation was directed at separating long-term reconstituting (LTR) stem cells in normal murine marrow from hematopoietic precursors detectable in short-term assays in vitro and in vivo, and then at determining whether purified LTR cells could themselves form colonies in culture. To do so, it was first necessary to identify culture conditions that would induce their growth while preserving their long- term reconstituting capacity. Marrow was cultured with various cytokines in liquid suspension for 4 days, after which the surviving LTR activity was quantitated in a competitive in vivo assay. Activity was preserved near input levels with combined murine c-kit ligand (KL), interleukin-1 (IL-1), IL-6, and IL-11. When the cultures also included tritiated or unlabeled thymidine, LTR potential was eliminated, indicating that essentially all LTR cells were induced into cell cycle with these cytokines. To purify them, marrow was sorted on the basis of Ly6A expression and Rhodamine 123 retention. The Ly6AhiRh123ls fraction contained 85% of total recovered LTR activity but only 1% of the recovered cells measured by multilineage colony formation in spleens or in vitro. This fraction was cultured in methyl cellulose with KL, IL-1, IL-6, and IL-11 for 4 to 6 days, after which colonies were isolated and injected into mice. High levels of permanent reconstitution were achievable in sublethally irradiated W41/W41 mice after the injection of a single reconstituting unit, and limiting dilution analysis estimated the frequency of multilineage LTR at 1 in 11,200 unpurified adult marrow cells. In either lethally irradiated normal or sublethally irradiated W41/W41 mice, 1-year lymphomyeloid reconstitutions were obtained from 1 in 65 to 84 colonies of 2 to 16 dispersed cells, but not from larger colonies or those with clumped cells. The results establish that resting marrow LTR cells can be separated from almost all of the more advanced clonogenic cells that are still pluripotential, can be induced to cycle in culture by defined cytokines with preservation of their reconstituting potential, and can be manipulated and assayed efficiently at single-cell and colony levels.  相似文献   
49.
50.
We report a rare case of acute liver failure due to embolization of the liver after an umbilical hernia repair in a patient with Child B liver cirrhosis and status posttransjugular intrahepatic portosystemic shunt (TIPSS). This patient initially presented with a symptomatic umbilical hernia. His umbilical vein was open (Cruveilhier–Baumgarten syndrome). After hernia repair the patient developed thrombosis of the umbilical vein with consequent partial embolization to, and acute failure of, the liver. The patient underwent successful emergency liver transplantation. This disease needs close collaboration among surgeons, gastroenterologists, hepatologists, radiologists, nutritionists, and transplant teams to establish an effective treatment plan.  相似文献   
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