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11.
In the present study, we evaluated the immunopotentiating efficacy of tuftsin against experimental murine aspergillosis in both normal and immunodebilitant BALB/c mice. The animals were challenged with an isolate of Aspergillus fumigatus (1x10(8) cfu/mouse) that was showing less susceptibility to lower doses of amphotericin B in murine animal model. Co-administration of the immunomodulator tuftsin and liposomised-amphotericin B was found to be highly effective in the treatment of systemic infection of A. fumigatus in both immunocompetent and leukopenic mice. Moreover, pre-treatment of mice with liposomised-tuftsin prior to challenging them with A. fumigatus infection and subsequent treatment with tuftsin-bearing liposomised-amphotericin B was found to be extremely efficient in successful elimination of fungal pathogen. In another set of experiments, tuftsin-mediated antigen-specific memory antibody response was also assessed by immunizing the animals with A. fumigatus cytosolic antigen. The animals that received a booster 150 days after the first immunization with tuftsin-liposomes-antigen showed more resistance to A. fumigatus infection in comparison with the na?ve animals.  相似文献   
12.
Various 1-arylidene-2-tetralones 1 had been shown previously to possess moderate cytotoxic properties unaccompanied by murine toxicity. The objective of the present investigation was to undertake different molecular modifications of representative members of series 1 with a view to discerning those structural features leading to increased potencies. All compounds were evaluated using human Molt 4/C8 and CEM T-lymphocytes as well as murine P388 and L1210 leukemic cells. The Mannich bases 2, 4, 5 and 7 possessed increased potencies compared to the corresponding unsaturated ketones 1 and in general were potent cytotoxics having IC50 values in the 0.2-10 microM range. QSAR using the cytotoxicity data for 2a-e suggested that potency was positively correlated with the size of the substituents in the arylidene aryl ring. Compounds 2a-f were evaluated using a panel of approximately 53 human tumour cell lines and, when all cell lines were considered, were more potent than the reference drug melphalan. In particular, marked antileukemic activity was displayed. Molecular modeling was utilized in order to evaluate whether the shapes of the different compounds contributed to the varying potencies observed. Representative compounds demonstrated minimal or no inhibiting properties towards human N-myristoyltransferase (NMT) and did not bind to calf thymus DNA. This study has revealed a number of unique lead molecules as candidate anti-neoplastic agents serving as prototypes for future development.  相似文献   
13.
In relation to the growing recent interest in the establishment of sperm‐mediated gene transfer (SMGT) technology as a convenient and effective method for the simple production of transgenic animals, in this study the possibility of using SMGT to produce transgenic caprine embryos was investigated for the first time. Buck sperm were directly incubated with different concentrations (0–500 ng) of pcDNA/his/Lac‐Z plasmid and used for IVF or ICSI. Sperm used for ICSI were categorized into motile or live‐immotile group before being injected into oocytes. In a separate experiment, dead sperm prepared by repeated freezing/thawing were used for DNA‐incubation before ICSI. Sham injection was carried out by intracytoplasmic injection of approximately the same volume of media containing different doses of DNA using an ICSI needle. Transgene expression and transmission were detected by X‐Gal staining and PCR analysis of developed embryos, respectively. A reasonable blastocyst rate was observed in all the groups. Only embryos in the sham group were negative for transgene transmission. Transgene expression was completely dependent on the delivery technique and status of sperm, and was only observed in the live‐immotile and dead ICSI groups. The results of this study showed that the technique (IVF vs. ICSI vs. sham injection), sperm status (motile vs. live‐immotile vs. dead) and to some extent DNA concentration affect embryo development, transgene transmission and expression. Mol. Reprod. Dev. 77:868–875, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
14.
Trace elements including Al, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sr, and Zn were analyzed in the scalp hair samples of women with malignant breast lesions, women with benign breast lesions, and healthy donors using atomic absorption spectrophotometric method. In the scalp hair of malignant-tumor patients, the highest average concentration was shown by Ca (1,187 μg/g), followed by Na (655 μg/g), Mg (478 μg/g), Zn (391 μg/g), Sr (152 μg/g), Fe (114 μg/g), and K (89.8), while in the case of benign-tumor patients, the average estimated element levels were 1,522, 1,093, 572, 457, 217, 80.4, and 74.7 μg/g, respectively. Most of the elements exhibited non-normal distribution evidenced by large spread, standard error, and skewness values. Mean concentrations of Ca (634 μg/g), Zn (206 μg/g), Mg (162 μg/g), Fe (129 μg/g), and Na (82.1 μg/g) were noteworthy in the scalp hair of healthy women. Average levels of Na, Sr, K, Cd, Co, Pb, Mg, Ca, Zn, Ni, Sb, and Mn were revealed to be significantly higher in the hair of malignant and benign patients compared to the healthy women; however, Fe, Cu, Al, and Cr were not significantly different in the scalp hair of the three groups. The quartile distributions of Ca, Cd, Co, Cr, K, Mg, Mn, Na, Ni, Pb, Sb, and Sr revealed maximum spread in the scalp hair of malignant and benign groups; nevertheless, Al, Cu, Fe, and Zn exhibited almost comparable quartile levels in the three groups. Strong correlation coefficients were found between Fe and Cd, Al and Na, Mn and Sr, Co and Cr, Cd and Cr, Pb and K, Pb and Mn, Cu and Na, and Al and Fe in the scalp hair of malignant-tumor patients, while Fe and K, Cd and Co, Na and Co, and Cr and Pb showed strong correlations in the scalp hair of benign-tumor patients, both of which were significantly different compared with the healthy subjects. Multivariate cluster analysis also revealed divergent clustering of the elements in the scalp hair of malignant and benign patients in comparison with the healthy women.  相似文献   
15.
Cationic antimicrobial peptides (CAMPs) are novel candidates for drug development. Here we describe design of six short and potent CAMPs (SA-1 to SA-6) based on a minimalist template of 12 residues H+HHG+HH+HH+NH2 (where H: hydrophobic amino acid and +: charged hydrophilic amino acid). Designed peptides exhibit good antibacterial activity in micro molar concentration range (1-32 μg/ml) and rapid clearance of Gram-positive and Gram-negative bacterial strains at concentrations higher than MIC. For elucidating mode of action of designed peptides various biophysical studies including CD and Trp fluorescence were performed using model membranes. Further based on activity, selectivity and membrane bound structure; modes of action of Trp rich peptide SA-3 and template based peptide SA-4 were compared. Calcein dye leakage and transmission electron microscopic studies with model membranes exhibited selective membrane active mode of action for peptide SA-3 and SA-4. Extending our work from model membranes to intact E. coli ATCC 11775 in scanning electron micrographs we could visualize different patterns of surface perturbation caused by peptide SA-3 and SA-4. Further at low concentration rapid translocation of FITC-tagged peptide SA-3 into the cytoplasm of E. coli cells without concomitant membrane perturbation indicates involvement of intracellular targeting mechanism as an alternate mode of action as was also evidenced in DNA retardation assay. For peptide SA-4 concentration dependent translocation into the bacterial cytoplasm along with membrane perturbation was observed. Establishment of a non specific membrane lytic mode of action of these peptides makes them suitable candidates for drug development.  相似文献   
16.
17.
To evaluate the subpopulation of corticotrophs in developing buffalo (Bubalus bubalis) fetus, pituitary glands were recovered (n=6 per group) from late first, second and third gestational female buffalo dams. The corticotrophs were identified by using specific antibodies against proopiomelanocortin (POMC) and adrenocorticotrophic hormone (ACTH) through immunohistochemistry. There was a significant (P≤0.05) increase of immunoreactive (ir) ir-ACTH cells during late 2nd trimester while, ir-POMC cells were more (P≤0.05) at late 3rd trimester of gestation as compared to other age groups. The quantity of co-localized cells for POMC and ACTH was significantly (P≤0.05) greater at the end of 1st gestation rather than 2nd and 3rd gestational fetal adenohypophyseal cells. This study is the first to demonstrate co-localization of POMC+ACTH and the affect of gestational age on the expression of these cells in buffalo fetus adenohypophysis.Key words: buffalo, corticotrophs, fetus, pituitary gland, immunohistochemistry  相似文献   
18.
Application of environmentally friendly enzymes to remove thin-film composite (TFC) reverse osmosis (RO) membrane biofoulants without changing the physico-chemical properties of the RO surface is a challenging and new concept. Eight enzymes from Novozyme A/S were tested using a commercially available biofouling-resistant TFC polyamide RO membrane (BW30, FilmTech Corporation, Dow Chemical Co.) without filtration in a rotating disk reactor system operated for 58 days. At the end of the operation, the accumulated biofoulants on the TFC RO surfaces were treated with the three best enzymes, Subtilisin protease and lipase; dextranase; and polygalacturonase (PG) based enzymes, at neutral pH (~7) and doses of 50, 100, and 150 ppm. Contact times were 18 and 36 h. Live/dead staining, epifluorescence microscopy measurements, and 5 μm thick cryo-sections of enzyme and physically treated biofouled membranes revealed that Subtilisin protease- and lipase-based enzymes at 100 ppm and 18 h contact time were optimal for removing most of the cells and proteins from the RO surface. Culturable cells inside the biofilm declined by more than five logs even at the lower dose (50 ppm) and shorter incubation period (18 h). Subtilisin protease- and lipase-based enzyme cleaning at 100 ppm and for 18 h contact time restored the hydrophobicity of the TFC RO surface to its virgin condition while physical cleaning alone resulted in a 50° increase in hydrophobicity. Moreover, at this optimum working condition, the Subtilisin protease- and lipase-based enzyme treatment of biofouled RO surface also restored the surface roughness measured with atomic force microscopy and the mass percentage of the chemical compositions on the TFC surface estimated with X-ray photoelectron spectroscopy to its virgin condition. This novel study will encourage the further development and application of enzymes to remove biofoulants on the RO surface without changing its surface properties.  相似文献   
19.
20.
The expression of genomic instability was studied at the phenotypical (morphological characters, electrophoretic spectra of seed storage proteins) and molecular (DNA amplification products) levels in interspecific hybrids (ISHs) from crosses of inbred lines of cultivated sunflower Helianthus annuus with perennial species of the genus Helianthus and in introgressive lines (ILs) produced on their basis. Unstable state of the locus determining the trait of lower branching was proved by the method of hybridological analysis. It was shown with the use of RAPD markers that the IL genome is characterized by instability even after long-term inbreeding (in generations F8-F12). In progenies of different combinations of interspecific crosses, identical polymorphic variants were revealed for a seed storage protein, helianthinin, and for DNA fragments homologous to structural genes of functionally important proteins, suggesting the nonrandom character of ISH genome variation. This variation may be determined by genome reorganizations under the action of a genome shock induced by interspecific hybridization. The factors inducing reorganizations in the genome include the activity of mobile genetic elements (MGEs). Using primers specific to different MGE families, nucleotide sequences with a high level of homology to the sequences of fragments of the mobile elements MuDR, Far1, CACTA, Stowaway, and Tourist were identified in the sunflower genome. The possibility of using MGE fragments for sunflower genotyping was demonstrated.  相似文献   
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