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51.
The study of central nervous system (CNS) leukemia has been hampered by the lack of a suitable animal model. We report that severe combined immunodeficiency (SCID) mice invariably develop rapidly progressive fatal CNS leukemia within 3 weeks after intravenous injection of NALM-6 pre-B acute lymphoblastic leukemia (ALL) cells. Colonization of the dura mater and subarachnoid space, usually of the distal spinal cord with occasional extension into the Virchow-Robin spaces of blood vessels subjacent to the meninges, followed involvement of bone marrow in the skull, vertebrae, and, occasionally, the appendicular skeleton. Occult CNS leukemia was detectable by polymerase chain reaction amplification of human DNA as early as 8 days postinoculation of leukemia cells. We used this in vivo model of human CNS leukemia to examine the therapeutic efficacy and toxicity of intrathecally administered B43 (anti-CD19)-pokeweed antiviral protein (PAP), an anti- B-lineage ALL immunotoxin directed against the pan-B-cell antigen CD19/Bp95. Intrathecal therapy with B43 (anti-CD19)-PAP immunotoxin at nontoxic dose levels significantly improved survival of SCID mice and was superior to intrathecal methotrexate therapy. 相似文献
52.
恰如其分的外周髓鞘形成取决于雪旺细胞增殖与分化进程间的平衡。丝氨酸/苏氨酸激酶(mTOR)整合多种环境因素,是细胞生长、代谢、发挥作用的中枢调节者。本文报道了一种mTOR的负性调节剂——结节性硬化复合体(TSC1),通过控制细胞增殖和髓鞘稳态,建立了雪旺细胞谱系进展和髓鞘形成的阶段依赖性程序。小鼠雪旺细胞祖细胞中TSC1的解离导致mTOR信号通路激活,继而导致雪旺细胞过量增殖,分化受阻,髓鞘形成减少。转录组分析显示,TSC1突变体中的mTOR活化使得polo样激酶(PLK)依赖性通路和细胞周期调节剂上调。弱化mTOR或者对PLK进行药理抑制部分挽救了因TSC1缺失导致的外周神经发育过程中的髓鞘形成减少。相较之下,成年小鼠成熟雪旺细胞中TSC1缺失可导致髓鞘的过度增殖和过度生长。本文的发现提示了TSC1-mTOR-PLK信号轴在控制雪旺细胞的发育过程中,从增殖到分化和髓鞘内稳态中起到的阶段特异性功能。 相似文献
53.
Javier Lucas Ramos Cristina Suárez Ferrer Joaquín Poza Cordón María Sánchez Azofra Jose Luis Rueda García Eduardo Martin Arranz Jorge Yebra Carmona Irene Andaluz García Maria Dolores Martín Arranz 《Gastroenterologia y hepatologia》2021,44(5):337-345
IntroductionThe dose of thiopurine drugs in combined treatments with anti-TNF in inflammatory bowel disease (IBD) has not been clearly established. The purpose of this study is to assess whether the dose of azathioprine influences clinical and biochemical response/remission rates, and anti-TNF drug levels/antibody formation.Material and methodsPatients with IBD on combined maintenance treatment with azathioprine and infliximab or adalimumab were selected. Based on the dose of azathioprine, two groups were defined (standard: 2–2.5 mg/kg/day; and decreased: less than 2 mg/kg/day).ResultsIn the IFX group, there were no statistically significant differences (p = 0.204) in the rates of remission (39% vs 41.3%), response (10% vs 21.7%) or failure (51.5% vs 37%) depending on the dose of thiopurine drugs. No differences were found between AZA-dose dependent IFX levels (2.46 vs 3.21 μg/mL; p = 0.211). In the adalimumab group, there were no statistically significant differences (p = 0.83) in the rates of remission (66% vs 56%), response without remission (15.38% vs 25%) or failure (18% vs 18%) depending on the dose of thiopurines. With respect to ADA-levels, no differences were found in both groups (7.69 vs 8.23 μg/mL; p = 0.37).ConclusionIn our experience, no statistically significant differences were found in either anti-TNF levels or clinical-biological response/remission rates based on doses of azathioprine. 相似文献
54.
Information regarding the regulation of monocyte chemoattractant protein-1 (MCP-1) in regression of the corpus luteum (CL) is limited. This study tested the hypothesis that endothelial cells derived from bovine CL are a source of MCP-1, and that proinflammatory cytokines, prostaglandin F2alpha (PGF2alpha), and progesterone regulate MCP-1 expression. Endothelial cells were treated without (Control) or with PGF2alpha (1 micro M), TNFalpha (100 ng/ml), interferon-gamma (IFNgamma, 200 IU/ml), and TNFalpha + IFNgamma for 24 and 48 h in the absence or presence of progesterone (P4, 250 ng/ml). Increases in MCP-1 mRNA and protein were observed in response to TNFalpha within 24 and 48 h of culture, respectively (P < 0.05). Interferon-gamma stimulated (P < 0.05) both MCP-1 mRNA and protein after 24 h of culture, and this effect was also sustained through 48 h of culture (P < 0.05). Cotreatment of cultures with TNFalpha + IFNgamma lead to further increases (P < 0.05) in MCP-1 in both 24- and 48-h cultures. Surprisingly, neither PGF2alpha nor P4 affected MCP-1 production. Subsequent experiments revealed that the endothelial cells lacked prostaglandin F2alpha receptor mRNA, and the MAPK pathway, although present and responsive to growth factor stimulation, was unresponsive to PGF2alpha stimulation. In summary, endothelial cells derived from bovine CL respond to TNFalpha and IFNgamma stimulation with an increase in MCP-1 secretion. In contrast, neither PGF2alpha nor P4 directly influenced endothelial expression of MCP-1. These results suggest that cytokines stimulate the synthesis of MCP-1 observed during PGF2alpha-induced luteal regression. 相似文献
55.
In vivo expression of the B7 costimulatory molecule by subsets of antigen-presenting cells and the malignant cells of Hodgkin's disease 总被引:10,自引:0,他引:10
Munro JM; Freedman AS; Aster JC; Gribben JG; Lee NC; Rhynhart KK; Banchereau J; Nadler LM 《Blood》1994,83(3):793-798
The B-lymphocyte/accessory-cell activation antigen B7 (BB1) has been shown in vitro to stimulate T-lymphocyte proliferation and cytokine production via CD28 present on the latter cells. In this study, benign lymphoid tissues, lymphomas, and extralymphoid inflammatory sites were examined immunohistochemically using anti-B7 and other relevant monoclonal antibodies. B7 was expressed by benign transformed germinal center B cells, as it was by B cells of follicular lymphomas. B7 was also expressed by a subpopulation (a mean of 31% to 65%) of macrophages and dendritic cells in a variety of lymphoid tissues. It was present in abundance on all macrophages constituting sarcoid granulomas in lymph nodes. In extralymphoid inflammation, 17% to 35% of macrophages expressed B7 only weakly. Cases of Hodgkin's disease showed expression of B7 by the majority of Reed-Sternberg cells or malignant mononuclear variants, a phenomenon that potentially contributes to the lymphocytic accumulation that is a feature of this condition. CD28+ T cells were seen in all areas where T cells were present. B7+ and CD28+ cells colocalized in, for example, lymphoid follicles, lymph node paracortex, sarcoid granulomas, and Hodgkin's disease tissue, indicating a potential for cellular interaction via these molecules at these sites. 相似文献
56.
Incorporating prognostically related auscultatory, M-mode, 2DE and recent Doppler echocardiographic features, the following strict criteria for establishing the diagnosis of mitral valve prolapse (MVP) have been advanced: 1. auscultatory; mid-to-late systolic clicks and a late systolic murmur at the apex or mid-to-late systolic clicks at the apex which move appropriately with maneuvers that alter LV volume or late systolic murmur at the apex in young patients (coinciding that a similar murmur in elderly population is non-specific for MVP); 2. two-dimensionally "targeted" M-mode criterion: marked (greater than 3 mm) late systolic buckling posterior to C-D line (moderate 2 mm late systolic buckling or 3 mm holosystolic displacement "arouse suspicion" but do not establish MVP); 3. two-dimensional echocardiographic criteria: severe bowing of leaflet(s) on the parasternal long axis and four-chamber view (mild to moderate bowing alone are unacceptable) or left atrial coaptation point; 4. Doppler echocardiographic criteria: moderate or severe Doppler mitral regurgitation with any degree of leaflet bowing or mild Doppler mitral regurgitation with at least moderate bowing of one leaflet (mild leaflet bowing and mild mitral regurgitation can be regarded as "probable MVP"). The concept of mitral valve prolapse syndrome encompasses that which was earlier described in patients with a high prevalence of symptoms. In controlled studies, however, it has become apparent that cardiac and psychiatric symptoms can be found as frequently in normal subjects as in those with MVP. These results indicate that clinicians may have erroneously diagnosed patients with MVP because of premature acceptance that MVP is the cause of a distinctive syndrome.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
57.
Juan David Farfán-Albarracín Cristina Lorena Ramírez-Sierra Oscar Mauricio Espitia Segura Sofy Helena Pérez Hugo Andrés Téllez Prada María Camila Rueda Rodríguez Ingrid Lemus Espitia Ana Maritza Bedoya 《Brain & development》2021,43(1):63-68
IntroductionThe ratio of cerebrospinal fluid (CSF) glucose and blood glucose is of major relevance, conducting to the diagnosis of hypoglycorrhachia, which is a sign of neuroinfection, as well as a number of neurological diseases of genetic or neoplastic etiology. Glucose in capillary sample (glucometry) is a low cost, readily available technique, as compared to venous glucose. This study aims to compare glucometry to venous glucose in the diagnosis of hypoglycorrhachia in pediatric population.MethodsProspective cross-sectional study based on data obtained from lumbar punctures in the period from February 2017 to January 2019 in a specialized pediatric institution in Colombia.Results97 patients were analyzed, aged 1 month to 17 years old, mean 7.67 years, 52 (53.61%) were female. 26 (26.8%) were diagnosed with hypoglycorrhachia. Pearson correlation coefficient for absolute venous and capillary glucose was 0.54, and 0.55 for the ratios of CSF glucose/venous glucose and CSF glucose/glucometry, which support a linear correlation between the variables in both, absolute values and ratios. Intraclass correlation coefficient was calculated for both, the venous glucose and glucometry ratios, which was 0.52, revealing a moderate agreement among the tests. Sensitivity and specificity of CSF glucose/glucometry, as compared to gold standard are 73.1% and 60.6% respectively; whereas predictive positive value (PPV) and negative predictive value (NPV), were 40.4% and 86.0%.ConclusionGlucometry cannot replace the glucose in venous sample in the diagnosis of hypoglycorrhachia in children. 相似文献
58.
Chi DX Yan GZ Wang WX Lin LM Zhang GF Shi Y 《Journal of medical engineering & technology》2013,37(5):233-237
Manometry of the alimentary tract is a valuable and widely used means to evaluate and diagnose the function of the alimentary tract. However, the measurement can be inconvenient due to the invasive method used, and the many factors affecting results. Research on colonic pressure data is even more insufficient. This paper deals with colonic pressure data via an improved method ensuring that pressure data of the whole colon is available. The data is analysed based on the learning vector quantization (LVQ) method. Testing results show that this method distinguishes the normal data and the abnormal data, consistently with the original diagnoses. This method can serve as an assistant diagnosis of colonic motility and contributes to further research on colonic motility based on pressure data. 相似文献
59.
60.