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1.
An intron-less phaseolin gene [15] was used to express phaseolin polypeptides in transgenic tobacco plants. The corresponding amounts of phaseolin immunoreactive polypeptides and mRNA were similar to those found in plants transformed with a bean genomic DNA sequence that encodes an identical -phaseolin subunit. These results justified the use of the intron-less gene for engineering of the phaseolin protein by oligonucleotide-directed mutagenesis. Each and both of the two Asn residues that serve as glycan acceptors in wild-type phaseolin were modified to prevent N-linked glycosylation. Wild-type (wti–) and mutant phaseolin glycoforms (dgly 1, dgly 2 and dgly 1,2) were localized to the protein body matrix by immunogold microscopy. Although quantitative slot-blot hybridization analysis showed similar levels of phaseolin mRNA in transgenic seed derived from all constructs, seed from the dgly 1 and dgly 2 mutations contained only 41% and 73% of that expressed from the wild-type control; even less (23%) was present in seed of plants transformed with the phaseolin dgly 1,2 gene. Additionally, the profile of 25–29 kDa processed peptides was different for each of the glycoforms, indicating that processing of the full-length phaseolin polypeptides was modified. Thus, although targeting of phaseolin to the protein body was not eliminated by removal of the glycan side-chains, decreased accumulation and stability of the full-length phaseolin protein in transgenic tobacco seed were evident.Abbreviations bp base pair(s) - DAF days after flowering - GUS -glucuronidase - kb kilobase - kDa kilodalton  相似文献   
2.
The study aimed to compare aerobic and aerobic/anoxic stabilization processes in terms of organic matter and the biomass removal efficiencies using a municipal sludge sample. The efficiency of stabilization process was assessed monitoring suspended solids (SS), volatile suspended solids (VSS), total and dissolved organic carbon (TOC, DOC), nitrate, nitrite, and phosphate parameters. The oxygen uptake rate (OUR) measurements were conducted to determine active biomass concentration. On the 30th day of the aerobic stabilization, the SS, VSS and TOC removal efficiencies were 22%, 28% and 55%, respectively. Under aerobic/anoxic conditions, removal efficiencies for SS, VSS and TOC were 25%, 27% and 67%. On the 17th day of the stabilization, SS and VSS removal rates were 60 mg SS/L day and 47 mg VSS/L day for aerobic and 102 mg SS/L day and 63 mg VSS/L day for aerobic/anoxic conditions, respectively. These findings reflected the higher stabilization performance of the aerobic/anoxic conditions. Based on respirometric results, the ratios of the active biomass were decreased to 30% and 24% for the 17th and 30th day of the aerobic stabilization, respectively. Such results have significant implications relative to the activity decrease quantification of the biomass as well as its further application potentials after aerobic or aerobic/anoxic sludge stabilization.  相似文献   
3.
The combined effects of diabetes and a 50 Hz, 5 mT RMS flux density sinusoidal magnetic field for 8 h a day, for 21 consecutive days on the permeation of Evans-blue dye through the blood-brain barrier were studied in male Wistar albino rats. Our results suggest that magnetic field has no effect on the blood-brain barrier permeability in normoglycemic animals, but that diabetic rats are vulnerable to magnetic fields.  相似文献   
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Methylmethane sulfonate (MMS) is an alkylating agent that may react with DNA and damage it. We investigated histological changes and apoptosis caused by MMS and the effects of curcumin on MMS treated mouse kidneys. Twenty-four mice were divided into four equal groups: controls injected with saline, a group injected with 40 mg/kg MMS, a group injected with 40 mg/kg MMS and given 100 mg/kg curcumin by gavage, and a group given 100 mg/kg curcumin by gavage. MMS caused congestion and vacuole formation, and elevated the apoptotic index significantly, but had no other effect on kidney tissue. Curcumin improved the congestion and vacuole formation caused by MMS and decreased the apoptotic index. Curcumin administered with MMS appears to decrease the deleterious effects of MMS on the kidney.  相似文献   
6.
Mercury in the environment that arises from organic and inorganic sources can cause irreversible damage to the nervous system. Toxicity may be direct or may arise from interactions with other metals in the environment. We evaluated the possible effects of mercury vapor on rat cerebellum. Twelve adult female rats were divided into control and experimental groups. The rats in the experimental group were exposed to mercury vapor for 9 h/day for 45 days. Cerebellar tissue samples were evaluated using stereology and for histopathology. The total number of Purkinje cells was estimated using a physical disector method. We found that in the experimental group, overall volume decreased and the number of Purkinje cells was reduced. We also found cellular damage including pycnotic nuclei, eosinophilic cytoplasm and vacuolization; these features were absent in the control group. We found that chronic exposure to inorganic mercury vapor is toxic to the cerebellum.  相似文献   
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In this study, we investigated the levels of serum Zn, Cu, Mg, Mn, Fe, ceruloplasmin (Cp), transferrin (Trf), and albumin in laryngeal carcinoma and correlated their levels with the cancer stage. The sera from 35 patients with laryngeal cancer (10 at stage II, 12 at stage III, and 13 at stage IV) were extracted before treatment and compared with those from the healthy control group (n=15). Although serum Fe and Mn concentrations were lower in the laryngeal cancer groups (for all stages) than in the control group, the difference was not statistically significant (p>0.05). The higher Cu (p<0.001) and Cp (p<0.01) and lower Zn (p<0.01), Mg (p<0.001), and Trf (p<0.01) concentrations were found in laryngeal cancer groups (for each stage) when compared to the control group. In the comparison of stages II, III, and IV (with each other), all parameters were found to be statistically not significant (p>0.05). On the other hand, no meaningful difference was found in terms of the serum albumin level. In our opinion, alterations in the level of trace elements and antioxidant proteins, important for many metabolic processes, in laryngeal cancer may not be a reason for but is, in fact, a consequence of the disease itself.  相似文献   
9.
A sensitive and selective assay for the determination of mesna and total mesna in tissue was developed and validated. After a simple homogenization, extraction and deproteinization step, mesna could be measured immediately by HPLC with an electrochemical detector provided with a sensitive wall-jet gold electrode. Total mesna (i.e., free mesna and mesna present in mesna disulfides and mixed mesna disulfides) could be measured after pre-column reduction with sodium borohydride to free mesna. The lower limit of quantification of mesna and total mesna was for both compounds 10 nmol/g. The assays for mesna and total mesna in tissue were linear over the ranges of 10-3000 and 10-10000 nmol/g, respectively. The within-day and between-day precisions of both methods were better than 9%. The within-day and between-day accuracy of the mesna assay ranged from 103.7 to 113.6%, whereas the accuracies of the total mesna assay ranged from 97.8 to 106.7%. Mesna in an EDTA containing tissue homogenate or in deproteinized tissue homogenate stored at -80 degrees C was stable for at least 12 weeks. Total mesna was stable under all conditions measured. The developed assays will be applied for the determination of the distribution of mesna and total mesna in tissues of the rat after administration of mesna or BNP7787.  相似文献   
10.
The number of clinical studies on gamma interferon (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha) and interleukin-4 (IL-4) in human brucellosis is limited. The present study was focused on IFN-gamma, TNF-alpha and IL-4 levels in acute brucellosis cases, in the acute phase and at the end of the treatment. The relation of these cytokines to traditional inflammation markers was also investigated. The study included 27 cases of acute brucellosis and 20 healthy volunteers who had no complaints. It was found that mean IFN-gamma and TNF-alpha levels, CRP (C-reactive protein) levels and ESR (erythrocyte sedimentation rate) values were significantly higher in acute brucellosis cases as compared to post-treatment values and values measured in the control group. In addition, IFN-gamma and TNF-alpha levels measured in the acute phase correlated with the increase in CRP levels and ESR values. Our results confirmed that IFN-gamma and TNF-alpha are involved in the pathophysiology of brucellosis and are closely related to the inflammatory activation of the disease. In view of the present findings, it is suggested that IFN-gamma and TNFalpha may be used for monitoring brucellosis.  相似文献   
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