Alloactivated long-term cultured human T lymphocytes express both HLA-DR and SB antigens but lack lymphocyte stimulation capacity

Cell populations obtained from mixed leukocyte cultures of 6- or 10-day duration were found specifically to restimulate primed lymphocytes detecting HLA-linked SB as well as HLA-D-associated antigens. After expansion in vitro (9-75 days) with medium containing interleukin 2, the cultured cells expressed the T lymphocyte markers detected in indirect immunofluorescence by monoclonal antibodies Lyt-3, OKT3, OKT4, OKT8, and had high levels of HLA-DR antigens. In addition, they were shown in cell-mediated lymphocytotoxicity specifically to express SB antigens of the donor B cell type. Despite their positivity for DR and SB antigens, such cultured T cells failed to restimulate either SB- or D-specific secondary lymphocyte proliferation. Homogeneous cloned populations of cultured T cells also lacked lymphocyte stimulation capacity. In contrast, B cell lines, which also expressed DR and SB antigens, were potent stimulators of both SB- or D-directed proliferation. These data show that the activated T lymphocytes which express both HLA-DR and SB antigens are by themselves unable to stimulate lymphocyte proliferation.     

Assessing the consequences of quarantines during a pandemic

The European Journal of Health Economics - This paper analyzes the epidemiological and economic effects of quarantines. We use a basic epidemiological model, a SEIR-model, that is calibrated to...     

Environmental covariates: effects on the power of sib-pair linkage methods

The effect of inclusion of environmental risk factors on the power of sib-pair linkage methods was tested for a qualitative trait. It was found that inclusion of an environmental variable did not increase the power of the Haseman-Elston (H-E) sib-pair nonparametric linkage analysis test. However, a significant increase in power was observed for both the H-E and affected-sib-pair tests, even in small samples, when persons unexposed to the environmental risk factor were coded as unknown.     

Induction of stress proteins in rat cardiac myocytes by antimony.

The effects of nonlethal concentrations of potassium antimonyl tartrate (PAT) were examined in cultured neonatal rat cardiac myocytes. PAT (5, 10 microM) significantly increased cellular reduced glutathione (GSH) and heme oxygenase activity after 18 h. GSH levels and heme oxygenase activity were increased 2.5- and 5.4-fold, respectively, by 10 microM PAT after 18 h. In addition, total cytochrome P450 levels were decreased by PAT after an 18-h exposure. PAT exposures were associated with the induction of specific stress proteins. Nonlethal concentrations of PAT produced a dose-dependent increase in HO-1, HSP70, and HSP25/27 protein levels but did not increase HSP60 levels. Pretreatment of cardiac myocytes with low concentrations of PAT (0.5-10 microM) protected against a subsequent lethal concentration of PAT (200 microM). This protection was blocked if cells were treated with the protein synthesis inhibitor cycloheximide. Results demonstrate that low concentrations of PAT increase GSH levels and stress protein synthesis, which may be responsible for the protection that low-level PAT exposure offers against the subsequent toxicity of higher concentrations of PAT.     

In vivo comparison of copper blood-pool agents: potential radiopharmaceuticals for use with copper-62

Two techniques for labeling of albumin with copper-67 (67Cu) and 62Cu were investigated; one using the native Cu(II) binding site of the protein and the other employing a bifunctional chelate, 6-bromoacetamidobenzyl-1,4,8,11-tetraazacyclotetradecane- N,N'N",N"'-tetraacetic acid (Br-benzyl-TETA or BAT), conjugated to the protein. Rat biodistribution experiments with 67Cu demonstrated retention of i.v. 67Cu-benzyl-TETA-albumin in the blood pool identical to co-injected 125I-albumin. By contrast, i.v. administration of either [67Cu]-Cu-acetate or [67Cu]-Cu-acetate pre-mixed with albumin results in relatively rapid clearance of blood-pool radioactivity as the tracer is excreted into the urine. The 62Cu-benzyl-TETA-albumin radiopharmaceutical was obtained in ca. 17% radiochemical yield (end of synthesis, without decay correction) following a procedure that can be completed in 15-18 min. In PET experiments with a baboon, myocardial blood volume images with 62Cu-benzyl-TETA-albumin were identical to those obtained with C15O. Use of the 62Cu-benzyl-TETA-albumin image for blood-pool subtraction of a 62Cu-PTSM myocardial perfusion image is illustrated. Copper-62-benzyl-TETA-HSA should be a useful, generator-produced radiotracer for the detection of the vascular pool at PET facilities without cyclotrons.     

Methadone versus morphine as a first-line strong opioid for cancer pain: a randomized, double-blind study.

PURPOSE: To compare the effectiveness and side effects of methadone and morphine as first-line treatment with opioids for cancer pain. PATIENTS AND METHODS: Patients in international palliative care clinics with pain requiring initiation of strong opioids were randomly assigned to receive methadone (7.5 mg orally every 12 hours and 5 mg every 4 hours as needed) or morphine (15 mg sustained release every 12 hours and 5 mg every 4 hours as needed). The study duration was 4 weeks. RESULTS: A total of 103 patients were randomly assigned to treatment (49 in the methadone group and 54 in the morphine group). The groups had similar baseline scores for pain, sedation, nausea, confusion, and constipation. Patients receiving methadone had more opioid-related drop-outs (11 of 49; 22%) than those receiving morphine (three of 54; 6%; P =.019). The opioid escalation index at days 14 and 28 was similar between the two groups. More than three fourths of patients in each group reported a 20% or more reduction in pain intensity by day 8. The proportion of patients with a 20% or more improvement in pain at 4 weeks in the methadone group was 0.49 (95% CI, 0.34 to 0.64) and was similar in the morphine group (0.56; 95% CI, 0.41 to 0.70). The rates of patient-reported global benefit were nearly identical to the pain response rates and did not differ between the treatment groups. CONCLUSION: Methadone did not produce superior analgesic efficiency or overall tolerability at 4 weeks compared with morphine as a first-line strong opioid for the treatment of cancer pain.     

Immunosuppressive effects of peritoneal fluids from ovarian cancer patients

Peritoneal fluid samples from 42 patients with ovarian carcinomas were tested for their suppressive effects on in vitro responses of normal lymphocytes. Suppression was detected both in a natural killer cell assay against K562 cells and in an assay measuring phytohemagglutinin-induced lymphoproliferation. There was no correlation between the level of immunosuppression and the 1-year survival. The greatest suppression was seen in radically operated patients and in patients with normal amounts of peritoneal fluid. Complete suppression was also seen in two patients operated for benign diseases. The results indicate that immunosuppression is not restricted to malignant ascites, but may be a normal function of the peritoneal fluid.