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131.
Machado L Jarrett R Morgan S Murray P Hunter B Hamilton E Crocker J Thomas W Steven N Ismail T Chapman A Adams DH Lee SP 《Cancer immunology, immunotherapy : CII》2009,58(1):85-94
Circulating T lymphocytes enter a tissue if they express appropriate chemokine receptors and adhesion molecules to engage ligands presented at this site. To aid rational development of T cell-based therapies for Hodgkin's lymphoma (HL), we have assessed the expression and function of homing receptors on tumour-infiltrating T cells in HL and compared them with T cells from unaffected lymph nodes and colorectal cancer tissue. Chemokine receptors CXCR3, CXCR4 and CCR7 were expressed on a large proportion of T cells within HL tissue and mediated chemotaxis to purified chemokine. The corresponding ligands (CXCL10, CXCL12, CCL21) were expressed on the malignant cells and/or vascular endothelium. Adhesion molecules including CD62L were widely expressed on HL-derived T cells and their corresponding ligands were detected on vessels within the tumour. This homing phenotype was distinct from T cells isolated from colorectal cancer, but matched closely the phenotype of T cells from unaffected lymph nodes. Thus, T cell recruitment to HL resembles entry of na?ve/central memory T cells into normal lymph nodes. This has important implications for current approaches to treat HL using T cells activated and expanded in vitro that lack CCR7 and CD62L expression. 相似文献
132.
Stem cell capability enhanced with cytokine administration is a promising treatment for myocardial infarction. Bone marrow stem cells (BMSCs) were isolated from C57BL/6 mice (8-12 weeks old) expressing GFP and characterized with c-kit and CD34. Infarcted heart tissue fragments were placed into dishes with BMSCs and medium supplemented with G-CSF, SCF, IGF-1 or combinations thereof were given to the BMSC-infarcted myocardium in vitro model. The IGF-1-G-CSF group showed significantly higher migration (67.7% ± 2.6) of c-kit+ BMSCs towards the ischemic tissue and expressed MEF-2 (43.7% ± 1.7). Of the single treatment groups, the G-CSF group demonstrated significantly higher migration of c-kit+ BMSCs (60.5 ± 2.7) with MEF-2 expression (38.7 ± 1.4). IGF-1 complements G-CSF and was relatively more significant in its effects on BMSC migration and cardiac lineage commitment towards ischemic heart tissue. 相似文献
133.
Muhammad Tariq Murtaza Memon Asif Jafferani Sana Shoukat Saqib Ali Gowani Rabeeya Nusrat Mehmood Riaz Junaid Patel Bushra Jamil Raymond A. Smego Jr. 《PloS one》2009,4(10)
Background
Cholera is an important infectious cause of secretory diarrhea. The primary symptom of infection is the sudden onset of watery diarrhea with subsequent volume depletion causing renal insufficiency. The objective of this research is to study the level of dehydration at presentation and subsequent fluid management in patients with cholera.Methods
This study was conducted on 191 patients of Cholera admitted at a tertiary care hospital in Karachi, Pakistan during the period of 5 years. Medical charts were evaluated retrospectively for initial hydration status, baseline lab investigations on admission and discharge and fluid therapy given to all the patients while their stay in the hospital and the data was analyzed on SPSS 15.0.Results
Out of the 191 patients, 83(43%) were males and 108 (57%) were females with mean age of 42.3 years (SD±18.34). The average duration of symptoms was 3.75 days (SD±2.04). Of 191 patients, 175 (92.1%) presented with dehydration, 80 (42.3%) were given Ringer''s Lactate (R/L) + Normal Saline (N/S), 45 (24%) patients were given R/L + N/S + Oral Rehydration Therapy (ORS), 27 (14.3%) of the patients were kept on R/L only and remaining were given various combinations of R/L, N/S, ORS and Dextrose Saline (D/S). On admission mean Blood Urea Nitrogen (BUN) was 24.54 (SD±16.6), mean creatinine was 2.47 (SD±2.35) and mean BUN/Creatinine ratio was 11.63 (SD±5.7).Conclusion
Aggressive fluid rehydration remains the cornerstone of management of cholera. Instead of presenting with a classical BUN/Creatinine ratio of >20∶1, patients with pre-renal failure in cholera may present with a BUN/Creatinine ratio of <15∶1. 相似文献134.
Association of Blood Lead (Pb) and Plasma Homocysteine: A Cross Sectional Survey in Karachi,Pakistan
Background
High blood lead (Pb) and hyperhomocysteinemia have been found to be associated with cardiovascular disease (CVD). Mean blood Pb and mean plasma homocysteine levels have been reported to be high in Pakistani population. The objective of the present study was to assess the relationship of blood Pb to the risk of hyperhomocysteinemia in a low income urban population of Karachi, Pakistan.Methodology/Principal Findings
In a cross sectional survey, 872 healthy adults (355 males, 517 females; age 18–60 years) were recruited from a low income urban population of Karachi. Fasting venous blood was obtained and assessed for blood Pb and plasma/serum homocysteine, folate, pyridoxal phosphate (PLP, a coenzymic form of vitamin B6) and vitamin B12. The study population had median (IQR) blood Pb of 10.82 µg/dL (8.29–13.60). Prevalence of high blood Pb (levels >10 µg/dL) was higher in males compared to females (62.5% males vs 56% females; p value = 0.05). Mean ± SD/median (IQR) value of plasma homocysteine was significantly higher in the highest quartile of blood Pb compared to the lowest quartile 16.13±11.2 µmol/L vs 13.28±9.7µmol/L/13.15 (10.33–17.81) µmol/L vs 11.09 (8.65 14.31) µmol/L (p value<0.001). Daily consumption of fruit juice had a positive influence on both levels of plasma homocysteine and blood Pb. Compared with the lowest quartile of blood Pb, the OR for hyperhomocysteinemia was 1.69 (95% CI, 1.00 to 2.85) for the fourth quartile when the model was adjusted for age, gender, folate and vitamin B12.Conclusions/Significance
This study showed a relationship between blood Pb and hyperhomocysteinemia in a general population of Karachi, Pakistan. The harmful effect of Pb on cardiovascular system could be due to its association with hyperhomocysteinemia. 相似文献135.
Samreen Mohsin Asma Maqbool Mehwish Ashraf Kauser Abdulla Malik 《Molecular biotechnology》2017,59(8):334-342
A significant portion of organic phosphorus comprises of phytates which are not available to wheat for uptake. Hence for enabling wheat to utilize organic phosphorus in form of phytate, transgenic wheat expressing phytase from Aspergillus japonicus under barley root-specific promoter was developed. Transgenic events were initially screened via selection media containing BASTA, followed by PCR and BASTA leaf paint assay after hardening. Out of 138 successfully regenerated To events, only 12 had complete constructs and thus further analyzed. Positive T1 transgenic plants, grown in sand, exhibited 0.08–1.77, 0.02–0.67 and 0.44–2.14 fold increase in phytase activity in root extracts, intact roots and external root solution, respectively, after 4 weeks of phosphorus stress. Based on these results, T2 generation of four best transgenic events was further analyzed which showed up to 1.32, 56.89, and 15.40 fold increase in phytase activity in root extracts, intact roots and external root solution, respectively, while in case of real-time PCR, maximum fold increase of 19.8 in gene expression was observed. Transgenic lines showed 0.01–1.18 fold increase in phosphorus efficiency along with higher phosphorus content when supplied phytate or inorganic phosphorus than control plants. Thus, this transgenic wheat may aid in reducing fertilizer utilization and enhancing wheat yield. 相似文献
136.
Boron is an essential plant micronutrient, but it is phytotoxic if present in excessive amounts in soil for certain plants
such as Artemisia annua L. that contains artemisinin (an important antimalarial drug) in its areal parts. Artemisinin is a sesquiterpene lactone
with an endoperoxide bridge. It is quite expensive compound because the only commercial source available is A. annua and the compound present in the plant is in very low concentration. Since A. annua is a major source of the antimalarial drug and B stress is a deadly threat to its cultivation, the present research was conducted
to determine whether the exogenous application of methyl jasmonate (MeJA) could combat the ill effects of excessive B present
in the soil. According to the results obtained, the B toxicity induced oxidative stress and reduced the stem height as well
as fresh and dry masses of the plant remarkably. The excessive amounts of soil B also lowered the net photosynthetic rate,
stomatal conductance, internal CO2 concentration and total chlorophyll content in the leaves. In contrast, the foliar application of MeJA enhanced the growth
and photosynthetic efficiency both in the stressed and non-stressed plants. The excessive B levels also increased the activities
of antioxidant enzymes, such as catalase, peroxidase and superoxide dismutase. Endogenous H2O2 and O2− levels were also high in the stressed plants. However, the MeJA application to the stressed plants reduced the amount of
lipid peroxidation and stimulated the synthesis of antioxidant enzymes, enhancing the content and yield of artemisinin as
well. Thus, it was concluded that MeJA might be utilized in mitigating the B toxicity and improving the content and yield
of artemisinin in A. annua plant. 相似文献
137.
Ismahil MA Hamid T Haberzettl P Gu Y Chandrasekar B Srivastava S Bhatnagar A Prabhu SD 《American journal of physiology. Heart and circulatory physiology》2011,301(5):H2050-H2060
Environmental triggers of dilated cardiomyopathy are poorly understood. Acute exposure to acrolein, a ubiquitous aldehyde pollutant, impairs cardiac function and cardioprotective responses in mice. Here, we tested the hypothesis that chronic oral exposure to acrolein induces inflammation and cardiomyopathy. C57BL/6 mice were gavage-fed acrolein (1 mg/kg) or water (vehicle) daily for 48 days. The dose was chosen based on estimates of human daily unsaturated aldehyde consumption. Compared with vehicle-fed mice, acrolein-fed mice exhibited significant (P < 0.05) left ventricular (LV) dilatation (LV end-diastolic volume 36 ± 8 vs. 17 ± 5 μl), contractile dysfunction (dP/dt(max) 4,697 ± 1,498 vs. 7,016 ± 1,757 mmHg/s), and impaired relaxation (tau 15.4 ± 4.3 vs. 10.4 ± 2.2 ms). Histological and biochemical evaluation revealed myocardial oxidative stress (membrane-localized protein-4-hydroxy-trans-2-nonenal adducts) and nitrative stress (increased protein-nitrotyrosine) and varying degrees of plasma and myocardial protein-acrolein adduct formation indicative of physical translocation of ingested acrolein to the heart. Acrolein also induced myocyte hypertrophy (~2.2-fold increased myocyte area, P < 0.05), increased apoptosis (~7.5-fold), and disrupted endothelial nitric oxide synthase in the heart. DNA binding studies, immunohistochemistry, and PCR revealed significant (P < 0.05) activation of nuclear factor-κB in acrolein-exposed hearts, along with upregulated gene expression of proinflammatory cytokines tumor necrosis factor-α and interleukin-1β. Long-term oral exposure to acrolein, at an amount within the range of human unsaturated aldehyde intake, induces a phenotype of dilated cardiomyopathy in the mouse. Human exposure to acrolein may have analogous effects and raise consideration of an environmental, aldehyde-mediated basis for heart failure. 相似文献
138.
Uzma Majid Mahmooduzzafar Tariq Omar Siddiqi Muhammad Iqbal 《Acta Physiologiae Plantarum》2014,36(2):307-314
Seeds of Cassia angustifolia Vahl., treated with various concentrations (0, 0.1, 0.15, 0.2 and 0.25 %) of Mancozeb, a broad-spectrum contact fungicide, were sown in field conditions to study the effect of the treatments on lipid peroxidation, proline accumulation and modulation of antioxidant system of seedlings obtained. Significant increase over the control was observed in treated plants for thiobarbituric acid-reactive substances content (up to 207 %), proline content (96 %) and total glutathione content (144 %), whereas the total ascorbate content decreased by 44 %. Increased enzymatic activity was recorded for ascorbate peroxidase (63 %), glutathione reductase (154 %) and superoxide dismutase (109 %), whereas catalase activity decreased by 58 % with 0.25 % Mancozeb treatment. The changes observed were dose-dependent, showing a strong correlation with the level of treatment. 相似文献
139.
Mohsin Ahmad Khan Faidad Khan Nadeem Ahmad Muhammad Islam Khan Ahmad Usman Zafar Tayyab Husnain 《Molecular biology reports》2014,41(3):1445-1451
Beta-urogastrone also known as human epidermal growth factor is a key member of epidermal growth factor family having role in cell proliferation and differentiation in vivo as well as in vitro. Human epidermal growth factor gene has been isolated from different tissues but the method of isolation is technically difficult and complicated as it deals with biopsies. Here we isolated mature partial human epidermal growth factor gene from Huh-7 cell line, amplified and abridged toward mature coding region with three steps PCR, sequenced for homology with wild type human epidermal growth factor gene, inbuilt with sites of interest and cloned in Pichia pastoris for expression study. Isolated mature human epidermal growth factor gene from Huh-7 cell line showed 100 % sequence homology to wild type human epidermal growth factor gene and gives the native expression for human epidermal growth factor peptide. In this study we report that Huh-7 cell line is an easy source for the particular gene of human epidermal growth factor isolation and we are also suggesting P. pastoris is an expression system to produce recombinant human epidermal growth factor of the therapeutic importance resembling to the natural human system. 相似文献