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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.
Prostaglandin E2 (PGE2) and leukotriene C4 (LTC4) are the metabolites of arachidonic acid (AA) that increase in forebrain following global ischemia and reperfusion. These mediators are highly potent vasoconstrictors of cerebral arteries leading to enhanced vascular permeability that induces the formation of vasogenic edema. In this study, after developing an experimental animal model simulating the concept of ischemic penumbra in the rat, the levels of PGE2 and LTC4 produced in the forebrain were measured and the effects of these mediators in short duration and prolonged reperfusion were investigated and then correlated with neuropathological findings. We found statistically significant reduction both in PGE2 and LTC4-like activities after just 10 min ischemia (p less than 0.05, p less than 0.05). PGE2-like activity significantly increased in the 4th and 60th min of reperfusion (p less than 0.05, p less than 0.05). In the 15th min of reperfusion, PGE2 was found to be significantly reduced (p less than 0.005) that may be due to the formation of free oxygen radicals by activation of PG hydroperoxidase reaction that inhibits PGE2 production in the cyclooxygenase pathway. LTs were not significantly increased in any reperfused group. Inhibition of the lipoxygenase pathway of AA metabolism may occur as a result of 15-HPETE (15-hydroperoxyeicosatetraenoic acid) production. Pathologically, edema and degeneration of brain tissue were seen beginning from the 4th min of reperfusion that reached a peak in the 60th min of reperfusion which is in accordance with biochemical changes in the damaged tissue.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
Lipoxygenase pathway products of arachidonic acid (AA) metabolism (known as leukotrienes, LTs) are produced in the brain during pathologic conditions such as ischemia, hemorrhage, trauma, and seizure in which the release of AA is sustained by the activation of local phospholipases. The most common type of LT in the central nervous system is an LTC4 which is a highly potent vasoconstrictor leading to increase in vascular permeability. In this study, we compared the serum (S) and cerebrospinal fluid (CSF) prostaglandin E2 (PGE2) and LTC4 levels in 13 consecutively admitted patients with acute cerebral ischemia aged 55-80 years with 10 age-matched controls. Patients with previous glucocorticosteroid and antiinflammatory drug usage were not included in the study. S and CSF samples were drawn during the first 72 h of the attack, and samples were evaluated by bioassay. There was no significant difference in S PGE2 and LTC4 values, whereas a significant difference was observed between CSF PGE2 and LTC4 values as compared with the control group. The high levels of CSF PGE2 and LTC4-like activity in acute cerebral ischemia may indicate that these mediators have a role to play in cerebral edema. The CSF PGE2/LTC4 ratio was also found to be reduced in the ischemic group implying higher LTC4 synthesis than PGE2 synthesis. In the light of these findings, we suggest that use of a selective antagonist of LTs may be helpful in reducing the ischemic penumbra during acute cerebral ischemia by controlling the vasogenic edema.  相似文献   
4.

Background

Neuronatin (NNAT) is an endoplasmic reticulum proteolipid implicated in intracellular signalling. Nnat is highly-expressed in the hypothalamus, where it is acutely regulated by nutrients and leptin. Nnat pre-mRNA is differentially spliced to create Nnat-α and -β isoforms. Genetic variation of NNAT is associated with severe obesity. Currently, little is known about the long-term regulation of Nnat.

Methods

Expression of Nnat isoforms were examined in the hypothalamus of mice in response to acute fast/feed, chronic caloric restriction, diet-induced obesity and modified gastric bypass surgery. Nnat expression was assessed in the central nervous system and gastrointestinal tissues. RTqPCR was used to determine isoform-specific expression of Nnat mRNA.

Results

Hypothalamic expression of both Nnat isoforms was comparably decreased by overnight and 24-h fasting. Nnat expression was unaltered in diet-induced obesity, or subsequent switch to a calorie restricted diet. Nnat isoforms showed differential expression in the hypothalamus but not brainstem after bypass surgery. Hypothalamic Nnat-β expression was significantly reduced after bypass compared with sham surgery (P = 0.003), and was positively correlated with post-operative weight-loss (R2 = 0.38, P = 0.01). In contrast, Nnat-α expression was not suppressed after bypass surgery (P = 0.19), and expression did not correlate with reduction in weight after surgery (R2 = 0.06, P = 0.34). Hypothalamic expression of Nnat-β correlated weakly with circulating leptin, but neither isoform correlated with fasting gut hormone levels post- surgery. Nnat expression was detected in brainstem, brown-adipose tissue, stomach and small intestine.

Conclusions

Nnat expression in hypothalamus is regulated by short-term nutrient availability, but unaltered by diet-induced obesity or calorie restriction. While Nnat isoforms in the hypothalamus are co-ordinately regulated by acute nutrient supply, after modified gastric bypass surgery Nnat isoforms show differential expression. These results raise the possibility that in the radically altered nutrient and hormonal milieu created by bypass surgery, resultant differential splicing of Nnat pre-mRNA may contribute to weight-loss.  相似文献   
5.
Molecular Biology Reports - The current study investigated the change in umbilical cord tissue and the number of markers of Wharton’s jelly mesenchymal stem cells (WJ-MSC) in pregnant women...  相似文献   
6.
BackgroundMany studies have presented virus sequences which suggest the existence of a variety of putative new phleboviruses transmitted by sandflies in the Old World. However, in most of these studies, only partial sequences in the polymerase or the nucleoprotein genes were characterised. Therefore to further our understand of the presence and potential medical importance of sandfly-borne phleboviruses that circulate in southern Anatolia, we initiated field campaigns in 2012 and 2013 designed to identify, isolate and characterise phleboviruses in sandflies in this regionConclusions/SignificanceThe results indicate that a variety of phleboviruses are co-circulating in this region of southern Anatolia. Based on our studies, these new viruses clearly belong to genetic groups that include several human pathogens. However, whether or not Toros and Zerdali viruses can infect humans and cause diseases such as sandfly fever remains to be investigated.  相似文献   
7.
正Dear Editor,The Poxviridae family is divided into Chordopoxvirinae and Entomopoxvirinae genera.Parapoxvirus is one of 11genera in the Chordopoxvirinae genus,including orf virus(ORFV),bovine papular stomatitis virus(BPSV),pseudocowpox virus(PCPV)and parapoxvirus of red deer in New Zealand(PVNZ)(Skinner et al.,2012).This virus,also known as contagious ecthyma or contagious pustular dermatitis,is a viral skin disease causing edematous proliferative lesions,most often in hairless skin  相似文献   
8.
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   
9.
10.
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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