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1.
The current studies demonstrate that MOPC-315 tumor cells secrete large amounts of interleukin-10 (IL-10), which contributes to the inhibitory activity of MOPC-315 culture supernatants for the in vitro generation of antitumor cytotoxicity by MOPC-315-immune spleen cells. Moreover, addition of neutralizing monoclonal anti-IL-10 antibody to the in vitro stimulation cultures of cells from the tumor infiltrated spleens of mice bearing a large MOPC-315 tumor resulted in the generation of enhanced anti-MOPC-315 cytotoxicity. In contrast, addition of monoclonal anti-IL-10 antibody to the in vitro stimulation cultures of splenic cells from mice that are in the final stages of immune-mediated tumor eradication as a consequence of low-dose melphalan (l-phenylalanine mustard; L-PAM) therapy (and whose spleens no longer contain metastatic tumor cells) did not lead to enhancement in the in vitro generation of antitumor cytotoxicity. The cessation of IL-10 secretion as a consequence of low-dose L-PAM therapy of MOPC-315 tumor bearers was found to be accompanied by the acquisition of the ability to secrete interferon (IFN) by the splenic cells. In addition, by day 2 after low-dose L-PAM therapy a drastic decrease in the amount of IL-10 secreted by the s.c. tumor nodules was noted, which preceded the accumulation of tumor-infiltrating lymphocytes capable of secreting IFN. Thus, low-dose L-PAM therapy of mice bearing a large MOPC-315 tumor leads to a shift in cytokine production from a Th2-type cytokine to a Th1-type cytokine, and it is conceivable that this shift in cytokine production plays an important role in the low-dose L-PAM-induced acquisition of antitumor immunity by hitherto immunosuppressed mice bearing a large MOPC-315 tumor.Supported by research grant IM-435 from the American Cancer Society and CA54413 from the National Cancer InstituteIn partial fulfillment of the requirements for the Doctor of Philosophy DegreeRecipient of career development award CA-01350 from the National Cancer Institute  相似文献   
2.
Plasma Physics Reports - In the region of the surface of the probe introduced into the plasma, there are emission flows that introduce changes in the determination of its parameters. Despite the...  相似文献   
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Background

Frequent painful vaso-occlusive crises (VOCs) were associated with mortality in the Cooperative Study of Sickle Cell Disease (CSSCD) over twenty years ago. Modern therapies for sickle cell anemia (SCA) like hydroxyurea are believed to have improved overall patient survival. The current study sought to determine the relevance of the association between more frequent VOCs and death and its relative impact upon overall mortality compared to other known risk factors in a contemporary adult SCA cohort.

Methods

Two hundred sixty four SCA adults were assigned into two groups based on patient reported outcomes for emergency department (ED) visits or hospitalizations for painful VOC treatment during the 12 months prior to evaluation.

Results

Higher baseline hematocrit (p = 0.0008), ferritin (p = 0.005), and HDL cholesterol (p = 0.01) were independently associated with 1 or more painful VOCs requiring an ED visit or hospitalization for acute pain. During a median follow-up of 5 years, mortality was higher in the ED visit/hospitalization group (relative risk [RR] 2.68, 95% CI 1.1-6.5, p = 0.03). Higher tricuspid regurgitatant jet velocity (TRV) (RR 2.41, 95% CI 1.5-3.9, p < 0.0001), elevated ferritin (RR 4.00, 95% CI 1.8-9.0, p = 0.001) and lower glomerular filtration rate (RR=2.73, 95% CI 1.6-4.6, p < 0.0001) were also independent risk factors for mortality.

Conclusions

Severe painful VOCs remain a marker for SCA disease severity and premature mortality in a modern cohort along with other known risk factors for death including high TRV, high ferritin and lower renal function. The number of patient reported pain crises requiring healthcare utilization is an easily obtained outcome that could help to identify high risk patients for disease modifying therapies.

Trial Registration

ClinicalTrials.gov NCT00011648 http://clinicaltrials.gov/  相似文献   
5.
The MCM2-7 complex is believed to function as the eukaryotic replicative DNA helicase. It is recruited to chromatin by the origin recognition complex (ORC), Cdc6, and Cdt1, and it is activated at the G(1)/S transition by Cdc45 and the protein kinases Cdc7 and Cdk2. Paradoxically, the number of chromatin-bound MCM complexes greatly exceeds the number of bound ORC complexes. To understand how the high MCM2-7:ORC ratio comes about, we examined the binding of these proteins to immobilized linear DNA fragments in Xenopus egg extracts. The minimum length of DNA required to recruit ORC and MCM2-7 was approximately 80 bp, and the MCM2-7:ORC ratio on this fragment was approximately 1:1. With longer DNA fragments, the MCM2-7:ORC ratio increased dramatically, indicating that MCM complexes normally become distributed over a large region of DNA surrounding ORC. Only a small subset of the chromatin-bound MCM2-7 complexes recruited Cdc45 at the onset of DNA replication, and unlike Cdc45, MCM2-7 was not limiting for DNA replication. However, all the chromatin-bound MCM complexes may be functional, because they were phosphorylated in a Cdc7-dependent fashion, and because they could be induced to support Cdk2-dependent Cdc45 loading. The data suggest that in Xenopus egg extracts, origins of replication contain multiple, distributed, initiation-competent MCM2-7 complexes.  相似文献   
6.
Effects of medium viscosity on kinetic parameters of poly(U) hydrolysis catalyzed by RNase from Bac. intermedius 7P (binase) were studied in solutions of sucrose (4-50 wt. %) and glycerol (35-62 wt. %) in Tris--sodium acetate buffer (pH 7.5) at 25 degreesC. The rate constant of reaction kcat was practically unchanged over a wide range of viscosities (1-15 cP for sucrose and 2.5-3 cP for glycerol). In glycerol solutions, kcat slightly increased with viscosity increase from 4 to 10 cP. Addition of NaCl to the buffer medium resulted in an inhibitory effect of Na+ on kcat, prevented by 50% sucrose or 60% glycerol. It is concluded that binase-catalyzed poly(U) cleavage occurs through a "tense"-substrate mechanism, similarly to reactions catalyzed by alpha-chymotrypsin, trypsin, and laccase.  相似文献   
7.
Summary : FT is a tool written in C++, which implements the Fourier analysis method to locate periodicities in aminoacid or DNA sequences. It is provided for free public use on a WWW server with a Java interface. Availability : The server address is http://o2.db. uoa.gr/FT Contact : shamodr@atlas.uoa.gr   相似文献   
8.
Lipid peroxidation (LPO) and antioxidant system functioning in the blood, liver and small intestine mucosal cells of rats under cadmium chloride intake and administration of the liposomal form of the biologically active supplement (BAS FLP-MD) have been studied. It is shown that cadmium chloride administration (1 mg/kg, 14 days) leads to the activation of the oxidative processes in the cells and decrease of the antioxidant enzyme activities including mitochondrial enzymes. The revealed inhibition of the hepatic superoxide dismutase (SOD) activity considerably determined by the effect on mitochondrial Cu, Zn-SOD. The effect of one-shot and long-term cadmium intake on the conjugation system and decrease of the tissue glutathione level were shown. BAS FLP-MD intake normalizes the oxidative processes possibly due to stabilization of the cellular components.  相似文献   
9.
A program of house dust sample collection and analysis has begun in Syracuse, New York, USA, in order to determine the feasibility of a geography-based exposure assessment for urban metals. The sampling program, and the protocols it employs, is described for two different types of wipe media, Ghost Wipes and Whatman Filters. Preliminary results show that strong spatial patterns of floor dust loading (mg dust per square foot) can be observed for data aggregated at a spatial scale of about 1600 m (~2.5 km2). Floor dust metal concentrations were similar to those found in other urban environments, with some regional variation. The median floor dust Pb concentration was ~108 mg · kg?1 for this initial data set of ~264 sampled residential locations, and varied from 50 to 1100 mg Pb · kg?1.  相似文献   
10.
Analysis of psychological, social, and psychophysiological mechanisms underlying the formation of adaptive responses during puberty demonstrated a significant dependence of adolescent behavioral, autonomic, and endocrine parameters on sociobiological factors that determine the identification and individualization of genetically determined behavioral programs. Comparison of the adaptive capabilities of students from an innovative educational institution and from a vocational school showed that the levels of completeness of their adaptation were different and depended on social support, typological features, and autonomic regulation.  相似文献   
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