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31.
In our study we have detected the antimicrobial effects of the aqueous, methanolic and chloroformic extracts of Rubia tinctorum, Carthamus tinctorius and Juglans regia on some airborne microorganisms; using the usual methods which are used routinely for this purpose in microbiology. Previous investigations have shown that extracts of these plants have antimicrobial effects on some bacteria such as Bacillus subtilis, Bacillus cereus, Bacillus mycoides, and also on some fungi specially Aspergillus niger, Penicillium expansum and Geotrichum candidum.The antimicrobial effects we have detected are 'microbicidal'. The aqueous and the chloroformic extracts had the most and the least microbicidal effects, respectively. The aqueous extracts of Carthamus tintorious and Juglans regia had the most and the least microbicidal effects respectively. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
32.
With respect to the limitations use of methyl bromide and phosphine, employing ionizing radiation to control stored product pests has attracted great attention. The aim of this study is the investigation of the combined effects of gamma irradiation as viable alternatives to synthetic insecticides and environmental management on mortality and sterility of Rhyzopertha dominica (Fabricius) in a wheat cultivar (Gascogen). The effect of doses range from 30 to 2000?Gy gamma irradiation in combination with manipulation of temperature (15, 21, 27 and 32?°C) and relative humidity (20%, 50%, 65% and 85%) on 5–10?days old adults of R. dominica in Gascogen cultivar of wheat were explored. The experiments were repeated three times and conducted in The Nuclear Agriculture Research School in Karaj and laboratory of shahid steki silo in shahre-kord. Probit analysis revealed that both temperature and relative humidity had combined effects when used with gamma irradiation. The lowest doses of gamma ray required to kill 25% (14.2?Gy) and 50% (610.8?Gy) of the population (LD25 and LD50) were recorded at 21?°C and 85% relative humidity respectively. The low dose for 99% mortality (LD99; 2386.7?Gy) was recorded for beetles maintained at 21?°C and 50% relative humidity. The effect of temperature (15, 21, 27 and 32?°C) on sterility caused by gamma irradiation was also investigated. The results showed that the F1 generation emerged only when the beetles were treated with doses of 0–100?Gy at 32?°C and 0–70?Gy at 27?°C. These results indicate that temperature and relative humidity play an important role in the susceptibility of the lesser grain beetle to gamma irradiation. The results suggest that controlling the efficiency of gamma radiation through environmental control allows the use of low doses of gamma radiation that have a less harmful effect on human health, non-target organisms and seed agronomic features.  相似文献   
33.
BackgroundGamma radiation effects on the erythrocyte membrane from three different functional parts, lipid bilayer, cytoskeleton and protein components. When the red cell membrane is exposed to radiation, it loses its integrity and hemoglobin leaks out. In addition, irradiation leads to lipid peroxidation and the products of this process, leading to hemolysis. The aim of the present study was to measure osmotic fragility (OF) of red blood cells and malondialdehyde (MDA) levels as a marker of oxidative injury in breast cancer patients treated with radiation and chemotherapy.Materials and MethodsThe OF test was performed using different concentrations of a salt solution. The measurement of MDA was done with chemical methods.11 The sampling was taken during three stages of treatment: first sample was taken before starting chemotherapy, the second sample was taken before radiation therapy and the third sample was taken after radiotherapy.ResultsNo statistically significant differences between levels of MDA in these three stages of treatment were observed. However, the comparison of mean levels of MDA showed an increase after radiotherapy. The OF rate did not show significant difference (P > 0.05) during the stages of treatment.ConclusionIn a standard treatment program of radiotherapy and chemotherapy lipid peroxidation level and OF do not significantly increase.  相似文献   
34.
Biological Trace Element Research - The kinetic reaction for changes in some essential mineral contents (iron, zinc, calcium, sodium, and copper) of silver carp canned in sunflower oil, soybean...  相似文献   
35.
Platinum-based drugs have been widely used in cancer treatment. However, their severe side effects have limited their use. So, researchers have been striving to find compounds with fewer side effects and greater efficacy, to overcome these drawbacks. Here, the cytotoxicity of platinum(II) complexes containing 2-(diphenylphosphino)pyridine ligands have been studied on human lung (A549), ovarian (SKOV3), breast (MCF-7) cancer, and normal breast (MCF-10A) cell lines. The most potent compound exhibits a marked cell growth-inhibitory effect against ovarian and lung cancer cells with IC50 values of 9.41 and 5.58 μM, respectively, which were significantly better than that observed for cisplatin (19.02, and 8.64 μM). Additionally, all complexes achieved significantly lower cytotoxicity towards MCF-10A. To investigate the interaction of complexes with DNA, an electrophoresis mobility shift assay was conducted, which indicated that complexes bind to DNA and affect its electrophoretic mobility. An analysis of apoptosis in A549 cells supported the conclusion that they inhibits cell proliferation via induction of apoptosis in a concentration-dependent manner. Molecular docking was also used to investigate the interactions of compounds with different DNA structures. These compounds have the ability to be a suitable pharmaceutical compound with further investigations in the field of cancer research.  相似文献   
36.
BACKGROUND: Anaplastic large cell lymphoma (ALCL) (Ki-1/CD-30 positive) is an uncommon lymphoproliferative disorder that may be of T cell or null cell type. ALCL has been reported in fine needle aspirations of lymph nodes and pleural or peritoneal fluid cytology. In human immunodeficiency virus (HIV)-positive patients, ALCL appears to be more common and run a more aggressive course. CASE: A 39-year-old black man, seropositive for HIV, presented with acute renal failure secondary to bilateral ureteral obstruction by a pelvic mass involving the urinary bladder. Bladder wash cytology and subsequent biopsy of the mass were diagnostic of ALCL. The ALCL was CD30+ and null cell type, with negative CD2, CD3, CD4, CD5, CD7, CD8, CD20, CD45, CD79a, ALK-1, granzyme B, cytokeratin (AE1/AE3), placental alkaline phosphatase (PLAP) and S-100. The patient expired 9 months after the diagnosis, despite aggressive therapy. CONCLUSION: This is a rare occurrence of ALCL (CD 30 positive, null cell type) in the urinary bladder in an HIV+ patient. Presumptive diagnosis was made by bladder wash cytology and subsequently confirmed by biopsy. Urinary cytologic examination is a useful diagnostic tool. In HIV+/immunosuppressed patients with urinary symptoms and an obstructive mass, ALCL should be considered in the differential diagnosis.  相似文献   
37.
C-terminal region of merozoite surface protein-1 of Plasmodium falciparum (PfMSP-1) isolated from different parts of the world revealed sequence variability, however no data exist on sequence heterogeneity of this region from Iran. To address this question, DNA encoding the carboxyl (C)-terminal region of PfMSP-1 was amplified in 144 Iranian P. falciparum clinical isolates, using allele type-specific primers. In this study both MAD20 (88.2%) and K1 (7.6%) types were detected. Sequence analysis of 33 and 92 fragments corresponding to pfmsp-1(42) and pfmsp-1(19) revealed eight (15MAD1-15MAD7 and 15KCH) and five [A1 (E/TSR/L), A2 (Q/KNG/F), A3 (E/KNG/F), A4 (E/TSG/L), and A5 (Q/KNG/L)] distinct haplotypes, respectively. E/TSG/L variant type was the predominant haplotype, and reported only from Thailand and India, but E/KNG/L is widespread in Africa, Asia, and Latin America; but not found among Iranian isolates. In summary, result of this study indicates limited antigenic diversity, and thus support the potential utility of the C-terminal region of PfMSP-1 in designing polyvalent vaccine constructs.  相似文献   
38.
A rapid procedure has been developed for the isolation of the photosystem two reaction centre complex (PS II RC) from a double mutant of Chlamydomonas reinhardtii, F54-14, which lacks the Photosystem one complex and the chloroplast ATPase. Thylakoid membranes are solubilised with 1.5% (w/v) Triton X-100 and the PS II RC purified by anion-exchange chromatography using TSK DEAE-650(S) (Merck). The complex has a pigment stoichiometry of approximately six chlorophyll a: two pheophytin a: one cytochrome b-559: one to two -carotene. It photoaccumulates reduced pheophytin and oxidised P680 in the presence of sodium dithionite and silicomolybdate, respectively. Immunoblotting experiments have confirmed the presence of the D1 and D2 polypeptides in this complex. The -subunit of cytochrome b-559 was identified by N-terminal sequencing. Comparison of the complex with the PS II RC from pea using SDS-polyacrylamide gel electrophoresis showed that their polypeptide compositions were similar. However, the -subunit of cytochrome b-559 from C. reinhardtii has a lower apparent molecular weight than the pea counterpart whereas the -subunit is larger.Abbreviations DM n-dodecyl -d-maltoside - RC reaction centre - SiMo silicomolybdate, SiMo12O40 4– - TAP Tris-acetate-phosphate  相似文献   
39.
Horseradish peroxidase (HRP) is an important heme-containing glyco-enzyme that has been used in many biotechnological fields. Valuable proteins like HRP can be obtained in sufficient amounts using Escherichia coli as an expression system. However, frequently, the expression of recombinant enzyme results in inclusion bodies, and the refolding yield is generally low for proteins such as plant peroxidases. In this study, a recombinant HRP was cloned and expressed in the form of inclusion bodies. Initially, the influence of few additives on HRP refolding was assessed by the one factor at a time method. Subsequently, factors with significant effects including glycerol, GSSG/DTT, and the enzyme concentration were selected for further optimization by means of the central composite design of response surface methodology (RSM). Under the obtained optimal condition, refolding increased about twofold. The refolding process was then monitored by the intrinsic fluorescence intensity under optimal conditions (0.35 mM GSSG, 0.044 mM DTT, 7 % glycerol, 1.7 M urea, and 2 mM CaCl2 in 20 mM Tris, pH 8.5) and the reconstitution of heme to the refolded peroxidase was detected by the Soret absorbance. Additionally, samples under unfolding and refolding conditions were analyzed by Zetasizer to determine size distribution in different media.  相似文献   
40.
Background aimsSeveral studies have reported functional improvement after transplantation of in vivo-derived neural progenitor cells (NPC) into injured spinal cord. However, the potential of human embryonic stem cell-derived NPC (hESC-NPC) as a tool for cell replacement of spinal cord injury (SCI) should be considered.MethodsWe report on the generation of NPC as neural-like tubes in adherent and feeder-free hESC using a defined media supplemented with growth factors, and their transplantation in collagen scaffolds in adult rats subjected to midline lateral hemisection SCI.ResultshESC-NPC were highly expressed molecular features of NPC such as Nestin, Sox1 and Pax6. Furthermore, these cells exhibited the multipotential characteristic of differentiating into neurons and glials in vitro. Implantation of xenografted hESC-NPC into the spinal cord with collagen scaffold improved the recovery of hindlimb locomotor function and sensory responses in an adult rat model of SCI. Analysis of transplanted cells showed migration toward the spinal cord and both neural and glial differentiation in vivo.ConclusionsThese findings show that transplantation of hESC-NPC in collagen scaffolds into an injured spinal cord may provide a new approach to SCI.  相似文献   
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