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51.
OBJECTIVE: In this experiment, we studied the chronic effects of NPY, as there were no data on long-term effects of NPY in vivo. METHODS: Complementary DNA encoding NPY was isolated, sequenced and cloned into the expression vector, pCEP4. The 6-23 clone 6 cell line was transfected with this clone. Two groups of 10 adult male WAG rats (180-250 g body weight) were injected with either untransfected 6-23 clone 6 or 6-23 clone 6 transfected with NPY cDNA [6-23 (NPY)]. After 8 weeks, the animals were killed, their plasma assayed for insulin. Pancreatic glucagon (PG), by RIA, and plasma glucose were measured. RESULTS: The transfected cells were shown to be producing fully processed, bioactive NPY. The expression of NPY was also confirmed by Northern blot analysis. The animals injected with 6-23 (NPY) cells gained significantly more weight than the controls, (on day 54, 31.89 +/- 3.56 vs. 24.1 +/- 4.12 g, n = 10, P < 0.05). Plasma insulin and PG increased significantly in NPY animals compared to controls. The total RNA extracted from tumours was analysed by Northern blotting and showed NPY mRNA expression in NPY animals, but not in controls. CONCLUSION: The long-term effects of NPY was confirmed by injection of the cells producing this peptide. 相似文献
52.
Karimi G Ramezani M Tahoonian Z 《Evidence-based complementary and alternative medicine : eCAM》2005,2(3):383-386
The protective effect of methanolic extract of milk thistle seeds and silymarin against cisplatin-induced renal toxicity in male rats after a single intraperitoneal injection of 3 mg kg cisplatin were studied. Over 5 days, cisplatin-treated rats showed tubular necrosis and elevation in blood urea nitrogen (BUN) and serum creatinine (Scr). Pretreatment of animals with silymarin (50 mg kg) or extract (0.6 g kg) 2 h before cisplatin prevented the tubular damage. Rats treated with silymarin or extract 2 h after cisplatin had BUN and Scr significantly lower than those receiving cisplatin, but mild to moderate necrosis was observed. These results suggested that milk thistle may protect against cisplatin-induced renal toxicity and might serve as a novel combination agent with cisplatin to limit renal injury. 相似文献
53.
Hassan Abolhassani Janet Chou Wayne Bainter Craig D. Platt Mahmood Tavassoli Tooba Momen Marzieh Tavakol Mohammad Hossein Eslamian Mohammad Gharagozlou Masoud Movahedi Mohsen Ghadami Amir Ali Hamidieh Gholamreza Azizi Reza Yazdani Mohsen Afarideh Alireza Ghajar Arash Havaei Zahra Chavoshzadeh Asghar Aghamohammadi 《The Journal of allergy and clinical immunology》2018,141(4):1450-1458
54.
Carsten Lippold Emil Segatto András Végh Burkhard Drerup Tatjana Moiseenko Gholamreza Danesh 《European spine journal》2010,19(3):427-434
The aim of this study was to analyze the correlation ratios between the sagittal back contour (flèche cervicale and lombaire,
trunk inclination) and selected parameters of craniofacial morphology in children. The patient sample consisted of 66 healthy
children with a mean age of 11.2 years (SD 1.6 years), of which 34 were male (mean age 11.5 years, SD 1.3 years) and 32 were
females (mean age 10.9 years, SD 1.9 years). The children were recruited during the preparation of the initial orthodontic
treatment records. Craniofacial morphology was analyzed by six angular measurements: facial axis, mandibular plane angle,
inner gonial angle, lower facial height, facial depth and maxilla position. Rasterstereography was used for reconstruction
of the spinal back sagittal profile. From the profile flèche cervicale, flèche lombaire and trunk inclination were determined
and the correlations with the craniofacial morphology were calculated (Pearson and Mann–Whitney U test). Significant correlations were found with respect to the inner gonial angle and the flèche cervicale, the mandibular
plane angle and the flèche lombaire, the inner gonial angle and the flèche lombaire, and the angular lower facial height and
the flèche lombaire, as well as the inner gonial angle and the trunk inclination. The craniofacial vertical growth pattern,
presented by mandibular plane angle, inner gonial angle and the angular lower facial height, and the correlation to flèche
cervicale and lombaire as well as trunk inclination reveal correlations between growth pattern and sagittal back contour. 相似文献
55.
56.
Parisa Fathi Rezaei Shamileh Fouladdel Seyed Mahmood Ghaffari Gholamreza Amin Ebrahim Azizi 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2012,20(1):101
Background and the purpose of the study
Natural products from plants have an important role in the development and production of new drugs mainly for cancer therapy. More recently, we have shown that the pericarp methanolic extract of Pistacia atlantica sub kurdica (with local name of Baneh) as a rich source of active biological components with high antioxidant and radical scavenging activities, has ability to cease proliferation and induce apoptosis in T47D human breast cancer cells. The present study aimed to clarify whether Baneh extract able to alter cell cycle progression of T47D cells or not.Methods
In order to study the possible effect of Baneh extract on cell cycle of T47D cells, we evaluated cell cycle distribution and its regulatory proteins by flow cytometry and western blot analysis respectively.Results
Baneh extract induced G0/G1 cell cycle arrest in conjunction with a marked decrease in expression of cyclin D1 and cdk4 that was strongly dependent on time of exposure. In parallel, Dox-treated T47D cells in early time points were accumulated on S phase, but after 48 h cell cycle progression was inhibited on G2/M. Dox promoted striking accumulation of cyclin B1 rapidly and enhanced cyclin A abundance.Conclusion
Taken together, our results establish that the antitumor activity of the pericarp extract of Baneh partly is mediated via cell cycle arrest and downregulation of cyclin D1 and cdk4 expression. These findings warrant further evaluation regarding the mechanism(s) of action of this promising anticancer agent. 相似文献57.
Thys B Saerens D Schotte L De Bleeser G Muyldermans S Hassanzadeh-Ghassabeh G Rombaut B 《Journal of virological methods》2011,173(2):300-305
Recently, single-domain recombinant antibody fragments (VHHs or nanobodies) against poliovirus type 1 were isolated. To examine the antigenicity of poliovirus using these recombinant VHHs, an alternative technique mimicking protein A immunoprecipitation had to be developed that was designed specifically for VHHs. The current study validated an affinity capturing assay that is based on the magnetic separation of unbound antigen and antigen-VHH complexes. The technique is simple, fast, reliable, quantitative and inexpensive and was employed to assess the reactivity of 15 VHHs for native infectious poliovirus (N antigen), heat-denatured virus (H antigen) and 14S subviral particles. Three distinct subsets of VHHs were tentatively distinguished based on their specificity for the antigens: one that binds only to 14S precursors, another that binds to the H antigen and a third that binds to the N antigen. Some VHHs of the latter two subsets bound 14S subviral particles with equal affinity but others had at least 100-fold less affinity for the precursors. All neutralizing VHHs were demonstrated to recognize N antigen and all N-specific VHHs were shown to be neutralizing. This study corroborates the findings that VHHs mainly target conformational epitopes and that they target additional epitopes as compared to classical antibodies. The described technique may be useful for epitope mapping and tracking conformational changes of proteins. 相似文献
58.
Parisa Fathi Rezaei Shamileh Fouladdel Shokoufeh Hassani Fatemeh Yousefbeyk Seyed Mahmood Ghaffari Gholamreza Amin Ebrahim Azizi 《Food and chemical toxicology》2012,50(3-4):1054-1059
Plants as important source of natural active components with anticancer effects commonly are different in structure and biological properties. The pericarp of Pistacia atlantica sub kurdica with local name of Baneh, a rich source of active phytochemicals, contains noticeable amounts of polyphenolic compounds, flavonoids and anthocyanins. Therefore, the antiproliferative, apoptosis induction and cell cycle alterations of Baneh were evaluated in human colon carcinoma HT29 cells. The Baneh extract (0.7 mg/ml) resulted in 50% growth inhibition similar to 500 nM of Doxorubicin (Dox) in HT29 cells after 72 h. The down-regulation of cyclin A protein by Baneh extract induced S phase delay in cell cycle progression of HT29 cells. Unlike the Baneh extract, Dox showed G2/M accumulation of HT29 cells which was associated with an increase in cyclin A and cyclin B1 protein expression. Furthermore, the induction of apoptosis following Baneh extract and Dox treatment in HT29 cells was confirmed by DNA fragmentation and translocation of phosphatidylserine. The morphological characteristics of apoptosis were also observed in HT29 cells exposed to the Baneh extract and Dox. These results suggest that due to the existence of bioactive components, methanolic extract of the Baneh has significant cytotoxic effects against human colon carcinoma HT29 cells. 相似文献
59.
Hassanpour G Mohebali M Raeisi A Abolghasemi H Zeraati H Alipour M Azizi E Keshavarz H 《Parasitology research》2011,108(6):1519-1523
The transmission of malaria by blood transfusion was one of the first transfusion-transmitted infections recorded in the world.
Transfusion-transmitted malaria may lead to serious problems because infection with Plasmodium falciparum may cause rapidly fatal death. This study aimed to compare real-time polymerase chain reaction (real-time PCR) with rapid
diagnostic test (RDT) and light microscopy for the detection of Plasmodium spp. in blood transfusion, both in endemic and non-endemic areas of malaria disease in Iran. Two sets of 50 blood samples
were randomly collected. One set was taken from blood samples donated in blood bank of Bandar Abbas, a city located in a malarious-endemic
area, and the other set from Tehran, a non-endemic one. Light microscopic examination on both thin and thick smears, RDTs,
and real-time PCR were performed on the blood samples and the results were compared. Thin and thick light microscopic examinations
of all samples as well as RDT results were negative for Plasmodium spp. Two blood samples from endemic area were positive only with real-time PCR. It seems that real-time PCR as a highly sensitive
method can be helpful for the confirmation of malaria infection in different units of blood transfusion organization especially
in malaria-endemic areas where the majority of donors may be potentially infected with malaria parasites. 相似文献
60.
The transmembrane domains (TMDs) of dengue virus type-1 M protein (DENV-1M) were reported to form cation-selective channels in artificial lipid bilayers. We further explored this observation using the two-electrode voltage clamp (TEVC) method on the Xenopus laevis oocytes expressing DENV PrM and M proteins. Using myc epitope tagged M proteins, M was first shown to adopt its predicted native topology in mammalian cells when expressed on its own. The recombinant proteins were then successfully expressed on the surface of Xenopus oocytes. Using influenza A M2 (Inf A/M2) protein as a control, we measured the conductance of oocytes expressing DENV proteins under hyperpolarized or low-pH conditions. Inf A/M2 showed pH-dependent, amantadine-sensitive channel activity that was consistent with previously published reports. However, no activity was detected for DENV proteins. We conclude that DENV PrM and M proteins do not show pH-activated ion channel activity. 相似文献