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81.
Baumgartner C; Morell A; Hirt A; Bucher U; Forster HK; Doran JE; Matter L; Brun del Re G; Wagner HP 《Blood》1988,71(5):1211-1217
Elimination of neoplastic B cell populations from autologous bone marrow grafts also removes normal B lymphocytes. This is potentially hazardous for the reconstitution of the immune system in patients undergoing high-dose chemotherapy and total body irradiation followed by autologous marrow rescue. Five pediatric patients with B cell non- Hodgkin's lymphoma in first remission undergoing such a regimen were studied. They received bone marrow pretreated with anti-Y 29/55 monoclonal antibody and complement. B and T lymphocyte subpopulations reached normal levels within 6 months after autologous bone marrow transplantation (ABMT), and serum immunoglobulin levels became normal within 4 to 9 months. Vaccination with diphtheria and tetanus toxoid, trivalent poliomyelitis vaccine of the Salk type, and pneumococcal capsular antigens (38 to 54 months after transplantation) gave rise to specific antibody production. ABO isoagglutinins could be demonstrated in all patients. The response pattern was similar to that of patients who received unmanipulated autologous bone marrow. It is concluded that ex vivo anti-Y 29/55 depletion of the marrow graft does not induce relevant disturbances of humoral immune functions. 相似文献
82.
Vinogradova MV Stone DB Malanina GG Karatzaferi C Cooke R Mendelson RA Fletterick RJ 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(14):5038-5043
Troponin senses Ca2+ to regulate contraction in striated muscle. Structures of skeletal muscle troponin composed of TnC (the sensor), TnI (the regulator), and TnT (the link to the muscle thin filament) have been determined. The structure of troponin in the Ca(2+)-activated state features a nearly twofold symmetrical assembly of TnI and TnT subunits penetrated asymmetrically by the dumbbell-shaped TnC subunit. Ca ions are thought to regulate contraction by controlling the presentation to and withdrawal of the TnI inhibitory segment from the thin filament. Here, we show that the rigid central helix of the sensor binds the inhibitory segment of TnI in the Ca(2+)-activated state. Comparison of crystal structures of troponin in the Ca(2+)-activated state at 3.0 angstroms resolution and in the Ca(2+)-free state at 7.0 angstroms resolution shows that the long framework helices of TnI and TnT, presumed to be a Ca(2+)-independent structural domain of troponin are unchanged. Loss of Ca ions causes the rigid central helix of the sensor to collapse and to release the inhibitory segment of TnI. The inhibitory segment of TnI changes conformation from an extended loop in the presence of Ca2+ to a short alpha-helix in its absence. We also show that Anapoe, a detergent molecule, increases the contractile force of muscle fibers and binds specifically, together with the TnI switch helix, in a hydrophobic pocket of TnC upon activation by Ca ions. 相似文献
83.
84.
Yael Gozlan Daniella Aaron Yana Davidov Maria Likhter Gil Ben Yakov Oranit Cohen-Ezra Orit Picard Oran Erster Ella Mendelson Ziv Ben-Ari Fadi Abu Baker Orna Mor 《Viruses》2022,14(3)
A comprehensive characterization of chronic HBV (CHB) patients is required to guide therapeutic decisions. The cumulative impact of classical and novel biomarkers on the clinical categorization of these patients has not been rigorously assessed. We determined plasma HBV-RNA and HBsAg levels, HBV in peripheral lymphocytes (PBMCs) and HBV mutation profiles in CHB patients. Patient demographics (n = 139) and classical HBV biomarkers were determined during a clinical routine. HBV-RNA in plasma and HBV-DNA in PBMCs were determined by RT-PCR. HBsAg levels were determined using Architect. In samples with HBV-DNA viral load >1000 IU/mL, genotype mutations in precore (PC), basal core promoter (BCP), HBsAg and Pol regions were determined by sequencing. Most patients (n = 126) were HBeAg-negative (HBeAgNeg) with significantly lower levels of HBV-RNA, HBV-DNA and HBsAg compared to HBeAg-positive (HBeAgPos) patients (p < 0.05). HBV genotype D prevailed (61/68), and >95% had BCP/PC mutations. Escape mutations were identified in 22.6% (13/63). HBeAgNeg patients with low levels of HBsAg (log IU ≤ 3) were older and were characterized by undetectable plasma HBV-DNA and undetectable HBV-RNA but not undetectable HBV-DNA in PBMCs compared to those with high HBsAg levels. In >50% of the studied HBeAgNeg patients (66/126), the quantitation of HBsAg and HBV-RNA may impact clinical decisions. In conclusion, the combined assessment of classical and novel serum biomarkers, especially in HBeAgNeg patients, which is the largest group of CHB patients in many regions, may assist in clinical decisions. Prospective studies are required to determine the real-time additive clinical advantage of these biomarkers. 相似文献
85.
The production of prostaglandin E2 (PGE2) by human amnion cells in primary monolayer culture was stimulated 2- to 150-fold by mouse epidermal growth factor (mEGF). The effect of mEGF on amnion cell PGE2 production was dependent on the time of treatment and the concentration of mEGF used. The rate of PGE2 production by these cells was maximal between 2 and 4 h of treatment with mEGF; thereafter, the rate of production of PGE2 declined. The stimulation of PGE2 production was maximal at concentrations of mEGF of greater than 5 ng/ml. A number of other growth factors, steroid and protein hormones, and various other test agents were ineffective or only minimally in stimulating PGE2 production by amnion cells. The stimulatory effect of mEGF on PGE2 production in these cells was dependent on the presence of serum in the culture medium; alternatively, mEGF was effective in stimulating PGE2 production by amnion cells in serum-free medium that was supplemented with arachidonic acid bound to albumin. Thus, we conclude that the marked stimulation of PGE2 production by amnion cells treated with mEGF is not due to an action of mEGF to stimulate the release of arachidonic acid from cellular glycerophospholipid storage forms; rather, these data are supportive of the conclusion that mEGF-stimulated PGE2 production is dependent on the presence of nonesterified, i.e., free, arachidonic acid in the medium. 相似文献
86.
幽门螺杆菌cagⅡ对胃上皮细胞IL-8基因转录的影响及机制 总被引:6,自引:0,他引:6
目的探讨HpcagⅡ对胃上皮细胞IL-8基因转录的影响及信号传导机制。方法构建
cagⅡ基因位点缺失Hp突变株及带有IL-8报告基因的人胃癌细胞系L5F11,用液体闪烁计数仪测定荧光素酶(IL8转录)活性,用ELISA法测定IL8蛋白浓度。结果所有Hp突变株诱导荧光素酶活性与IL8蛋白浓度较亲代菌株26695均降低[(0.13±0.01)×cpm比(0.59±0.05)×(P<0.01);(0.73±0.13)ng/ml比(2.22±0.65)ng/ml,(P<0.05)]。PTK抑制剂herbimycinA不仅抑制Hp诱导的荧光素酶活性[(0.71±0.18)×cpm比(1.51±0.23)×cpm,(P<0.05)],而且抑制IL-8蛋白表达[(0.83±0.41)ng/ml比(3.22±0.59)ng/ml,(P<0.05)],但herbimycinA对TNFα诱导的荧光素酶活性及IL8蛋白表达均无影响(P均>0.05);PKA抑制剂H7抑制TNFα诱导的荧光素酶活性[(0.74±0.16)×cpm比(2.62±0.26)×cpm,(P<0.001)]及IL8蛋白表达[(1.45±0.38)ng/ml比(4.12±0.43)ng/ml,(P<0.01)],而对Hp诱导的荧光素酶活性无影响(P>0.05)。结论HpcagⅡ中的多基因能够调节胃上皮细胞IL-8基因转录,且这一作用主要经蛋白酪氨酸激酶途径。 相似文献
87.
Richard M Mendelson 《Journal of Medical Imaging and Radiation Oncology》2020,64(3):353-360
Inappropriate diagnostic imaging (DI) is a burgeoning issue and embraces its overuse and its misapplication. The obverse problem is one of underuse – that is when patients who should undergo imaging fail to do so. This article attempts to define these problems, examines the causes and effects and suggests some potential solutions. 相似文献
88.
Ethanol at low doses produces a release of punished responding in an operant rat conflict test similar to that observed for benzodiazepines and phenobarbital. It has been hypothesized that these anti-punishment effects are mediated via the GABA-benzodiazepine receptor-ionophore complex but not at the benzodiazepine binding site. In the present study isopropylbicyclophosphate (IPPO), which binds at the picrotoxinin site, reversed the release of punished responding produced by ethanol, pentobarbital and chlordiazepoxide; at low doses IPPO (less than 10 micrograms/kg) appeared to be most effective against ethanol but at higher doses (greater than 15 micrograms/kg) was also effective against pentobarbital and chlordiazepoxide. At still higher doses IPPO produced a decrease in punished and unpunished responding. These results suggest that the "anxiolytic" actions of ethanol may involve a direct action on the GABA-benzodiazepine receptor-ionophore complex and this action may underlie some of the intoxicating effects of ethanol. 相似文献
89.
Kremer CL Klein RR Mendelson J Browne W Samadzedeh LK Vanpatten K Highstrom L Pestano GA Nagle RB 《The Prostate》2006,66(11):1203-1212
BACKGROUND: The PI3K/AKT/mTOR pathway is central to prostate cancer progression. A preliminary investigation of immuno-histochemical expression of mammalian target of rapamycin (mTOR) pathway markers was undertaken to identify patterns of expression in prostate tissue. METHODS: Immunohistochemistry was performed on a custom-made prostate tissue array. Mean long scores and variability of long scores for each marker were recorded for normal lumenal cells, prostate intraepithelial neoplasia (PIN), and cancer. RESULTS: Expression of PTEN decreased and mTOR signaling pathway markers increased in PIN and in cancer as compared to normal cells in the majority of samples. Overexpression of 4E-BP1 and p-4E-BP1 was observed in PIN and cancer. However, in cancer, the overexpression of 4E-BP1 was significantly higher than with any other marker. DISCUSSION: Results suggest that 4E-BP1 overexpression is strongly associated with prostate cancer, especially when combined with PTEN and mTOR expression data. Hierarchical clustering analysis utilizing PTEN, mTOR, and 4E-BP1 separated normal from cancer cell populations in most cases. 相似文献
90.
AC Winter K Berger JE Buring & T Kurth 《Cephalalgia : an international journal of headache》2009,29(2):269-278
We evaluated the association of body mass index (BMI) with migraine and migraine specifics in a cross-sectional study of 63 467 women aged ≥ 45 years, of whom 12 613 (19.9%) reported any history of migraine and 9195 had active migraine. Compared with women without migraine and a BMI < 23 kg/m2 , women with a BMI ≥ 35 kg/m2 had adjusted odds ratios (ORs) (95% confidence intervals) of 1.03 (0.95, 1.12) for any history of migraine. Findings were similar for active migraineurs. Women with a BMI of ≥ 35 kg/m2 had increased risk for low and high migraine frequency, with the highest estimate for women who reported daily migraine. Compared with women with the lowest associated risk (migraine frequency < 6 times/year; BMI between 27.0 and 29.9 kg/m2 ), women with a BMI ≥ 35 kg/m2 had an OR of daily migraine of 3.11 (1.12, 8.67). Among the women with active migraine, a BMI ≥ 35 kg/m2 was associated with increased risk of phonophobia and photophobia and decreased risk of a unilateral pain characteristic and migraine aura. Our data confirm previous findings that the association between BMI with migraine is limited to migraine frequency and specific migraine features. 相似文献