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31.
This study was done to determine the degree of metals and heavy metals in some bee pollen sample as biological indicator for environmental pollution. Sample were collected from industrial, urban and agricultural areas of Jordan in year 2017. Eight metals (As, Cd, Cu, Mg, Pb, Ni, Se, and Zn) continents analyzed by using Inductively Coupled Plasma Optical Emission Spectrum, (ICP-OES).Results were statistically interpreted by using ANOVA analysis. Metals content in bee pollen from Jordan and China were determined within the following ranges (minimum–maximum mg/kg); Cu (copper): 11.338–0.032, Zn (Zinc): 77.022–25.24, Ni (Nickel): 2.839 to <0.01, Se (Selenium): 3.03 to <0.04, Mg (Magnesium): 1575.19–641.388, Pb (Lead): 2.567 to <0.03, Cd (Cadmium): <0.005, As (Arsenic): <0.02. The results showed that there were no statistically significant differences among metals in the bee pollen. It has also found that bee pollen produced in Jordan may be a good source of some trace elements like Se and Mg and can be used as an environmental indicator and for quality control.  相似文献   
32.
We have recently reported the results of a phase II trial in which two TroVax [modified vaccinia ankara (MVA) encoding the tumour antigen 5T4] vaccinations were given to patients both pre- and post-surgical resection of liver metastases secondary to colorectal cancer (CRC). 5T4-specific cellular responses were assessed at the entry and 2 weeks after each vaccination by proliferation of fresh lymphocytes and ELISA for antibody responses; 18 from the 19 CRC patients mounted a 5T4-specific cellular and/or humoral response. Here, we present a comparison of individual and between patient responses over the course of the treatments using cryopreserved peripheral blood mononuclear cells (PBMC) samples from the baseline until after the fourth vaccination at 14 weeks. Assays used were proliferation assay with 5T4-Fc fusion protein, overlapping 32mer 5T4 peptides, MVA-LacZ and MVA-5T4 infected autologous monocytes. Responses to 5T4 protein or one or more peptide pools were pre-existing in 12/20 patients and subsequently 10 and 12 patients showed boosted and/or de novo responses, respectively. Cumulatively, 13/20 patients showed proliferative responses by week 14. We also assessed the levels of systemic T regulatory cells, plasma cytokine levels, phenotype of tumour-infiltrating lymphocytes including T regulatory cells and tumour HLA class I loss of expression. More than half of the patients showed phenotypes consistent with relative immune suppression and/or escape highlighting the complexity of positive and negative factors challenging any simple correlation with clinical outcome.  相似文献   
33.

Purpose

CD4+CD25+ regulatory T (Treg) cells are present in increased numbers in patients with advanced cancer and CD25+ T cell depletion potentiates tumour immunity in animal models. The aim of this study was to assess the feasibility and safety of adoptive transfer of CD25+ depleted autologous T cells in patients with advanced renal cell carcinoma and to examine resulting changes in lymphocyte subsets.

Patients and methods

Six patients with advanced renal cell carcinoma underwent leukapheresis followed by conditioning chemotherapy with cyclophosphamide and fludarabine. The autologous leukapheresis product was depleted of CD25+ cells using CliniMACS® System then re-infused into the patient.

Results

Efficient CD25+ depletion from all leukapheresis products was achieved and 0.55–5.87 × 107/kg CD3+ cells were re-infused. Chemotherapy related haematological toxicity was observed, but blood counts recovered in all patients allowing discharge after a mean inpatient stay of 21 days. One patient subsequently developed a rapidly progressive neurological syndrome. A transient reduction in CD25+ subset was noted in the peripheral blood of 5 out of 6 patients with evidence of increased T cell responses to PHA in 4 out of 6 patients. One patient showed increased specific proliferative responses to the tumour associated antigen h5T4 coinciding with the nadir of Treg cells.

Conclusions

Given the transient nature of the reduction in CD25+ subset and the observed toxicity there is a need to explore further strategies to improve the safety and efficacy of this approach. Nevertheless, the results provide proof of concept in potentiation of tumour antigen T cell responses when Treg cell levels are depleted.
  相似文献   
34.
Caveolae are invaginated membrane structures with high levels of cholesterol, sphingomyelin, and caveolin protein that are predicted to exist as liquid-ordered domains with low water permeability. We isolated a caveolae-enriched membrane fraction without detergents from rat lung and characterized its permeability properties to nonelectrolytes and protons. Membrane permeability to water was 2.85 ± 0.41 x 10–3 cm/s, a value 5–10 times higher than expected based on comparisons with other cholesterol and sphingolipid-enriched membranes. Permeabilities to urea, ammonia, and protons were measured and found to be moderately high for urea and ammonia at 8.85 ± 2.40 x 10–7and 6.84 ± 1.03 x 10–2 respectively and high for protons at 8.84 ± 3.06 x 10–2 cm/s. To examine whether caveolin or other integral membrane proteins were responsible for high permeabilities, liposomes designed to mimic the lipids of the inner and outer leaflets of the caveolar membrane were made. Osmotic water permeability to both liposome compositions were determined and a combined inner/outer leaflet water permeability was calculated and found to be close to that of native caveolae at 1.58 ± 1.1 x 10–3 cm/s. In caveolae, activation energy for water flux was high (19.4 kcal/mol) and water permeability was not inhibited by HgCl2; however, aquaporin 1 was detectable by immunoblotting. Immunostaining of rat lung with AQP1 and caveolin antisera revealed very low levels of colocalization. We conclude that aquaporin water channels do not contribute significantly to the observed water flux and that caveolae have relatively high water and solute permeabilities due to the high degree of unsaturation in their fatty acyl chains. lipid rafts; microdomains; cholesterol; aquaporin; caveolin  相似文献   
35.

Background

Minocycline, a second-generation tetracycline antibiotic, exhibits anti-inflammatory and neuroprotective effects in various experimental models of neurological diseases, such as stroke, Alzheimer’s disease, amyotrophic lateral sclerosis and spinal cord injury. However, conflicting results have prompted a debate regarding the beneficial effects of minocycline.

Methods

In this study, we analyzed minocycline treatment in organotypic spinal cord cultures of neonatal rats as a model of motor neuron survival and regeneration after injury. Minocycline was administered in 2 different concentrations (10 and 100 µM) at various time points in culture and fixed after 1 week.

Results

Prolonged minocycline administration decreased the survival of motor neurons in the organotypic cultures. This effect was strongly enhanced with higher concentrations of minocycline. High concentrations of minocycline reduced the number of DAPI-positive cell nuclei in organotypic cultures and simultaneously inhibited microglial activation. Astrocytes, which covered the surface of the control organotypic cultures, revealed a peripheral distribution after early minocycline treatment. Thus, we further analyzed the effects of 100 µM minocycline on the viability and migration ability of dispersed primary glial cell cultures. We found that minocycline reduced cell viability, delayed wound closure in a scratch migration assay and increased connexin 43 protein levels in these cultures.

Conclusions

The administration of high doses of minocycline was deleterious for motor neuron survival. In addition, it inhibited microglial activation and impaired glial viability and migration. These data suggest that especially high doses of minocycline might have undesired affects in treatment of spinal cord injury. Further experiments are required to determine the conditions for the safe clinical administration of minocycline in spinal cord injured patients.  相似文献   
36.
Cadmium can enter water, soil, and food chain in amounts harmful to human health by industrial wastes. The use of intact and NaOH-treated dried algal tissues (Hydrodictyon reticulatum), a major ecosystem bio-component, for Cd removal from aqueous solutions was characterized. Cadmium biosorption was found to be dependent on solution pH, bioadsorbent dose, the interaction between pH and dose, contact time, and initial Cd concentration. The experimental results indicated that the biosorption performance of alkaline-treated algal tissues was better than that of intact tissues. The maximum biosorption capacities were 7.40 and 12.74 mg g?1 for intact and alkaline-treated bioadsorbents, respectively, at optimum operating conditions. Biosorption reaches equilibrium after 24 and 240 minutes of contact, respectively, for alkaline-treated and intact bioadsorbents. Cadmium biosorption was best fitted to Langmuir isotherm model (R2 ≈ 0.99) and the kinetic study obeyed the pseudo-second-order kinetic model, which suggests chemisorption as the rate-limiting step in the biosorption process. Alkaline-treated algal tissues can be used as a new material of low-cost bioadsorbent for continuous flow rate treatment systems.  相似文献   
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38.
The effectiveness of attenuated Salmonella in inhibiting tumor growth has been demonstrated in many therapeutic models, but the precise mechanisms remain incompletely understood. In this study, we show that the anti-tumor capacity of Salmonella depends on a functional MyD88-TLR pathway and is independent of adaptive immune responses. Since myeloid suppressor cells play a critical role in tumor growth, we investigated the consequences of Salmonella treatment on myeloid cell recruitment, phenotypic characteristics, and functional activation in spleen and tumor tissue of B16.F1 melanoma-bearing mice. Salmonella treatment led to increased accumulation of splenic and intratumoral CD11b+Gr-1+ myeloid cells, exhibiting significantly increased expression of various activation markers such as MHC class II, costimulatory molecules, and Sca-1/Ly6A proteins. Gene expression analysis showed that Salmonella treatment induced expression of iNOS, arginase-1 (ARG1), and IFN-γ in the spleen, but down-regulated IL-4 and TGF-β. Within the tumor, expression of iNOS, IFN-γ, and S100A9 was markedly increased, but ARG1, IL-4, TGF-β, and VEGF were inhibited. Functionally, splenic CD11b+ cells maintained their suppressive capacity following Salmonella treatment, but intratumoral myeloid cells had significantly reduced suppressive capacity. Our findings demonstrate that administration of attenuated Salmonella leads to phenotypic and functional maturation of intratumoral myeloid cells making them less suppressive and hence enhancing the host’s anti-tumor immune response. Modalities that inhibit myeloid suppressor cells may be useful adjuncts in cancer immunotherapy.  相似文献   
39.
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