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131.
The anti-inflammatory and redox protective effects of the citronellal (CT) were evaluated using in vivo and in vitro tests. Intraperitoneal (i.p.) administration of CT (50, 100, and 200 mg/kg) inhibited (p < 0.05) the carrageenan-induced leukocyte migration to the peritoneal cavity. Additionally, the carrageenan- and arachidonic acid-induced rat hind paw edema was significantly inhibited (p < 0.05) by i.p. administration of 100 and 200 mg/kg of the compound. When the redox activity was evaluated, CT (200 mg/kg) significantly reduced hepatic lipoperoxidation (p < 0.001), as well as oxidation of plasmatic (p < 0.05) and hepatic (p < 0.01) proteins. The results of the present study support the hypothesis that CT possesses anti-inflammatory and redox protective activities. It is suggested that its effects are associated with the inhibition of the enzymes in the arachidonic acid pathway, which prevent cell migration by inhibiting leukotriene production, edema formation and the increase of reactive oxygen species in tissues. Therefore, CT is of potential benefit to manage inflammatory disorders and correlated damages caused by oxidant agents.  相似文献   
132.
The solution structure of reduced Clostridium pasteurianum rubredoxin (MW 6100) is reported here. The protein is highly paramagnetic, with iron(II) being in the S=2 spin state. The Hβ protons of the ligating cysteines are barely observed, and not specifically assigned. Seventy-six percent of the protons have been assigned and 1267 NOESY peaks (of which 1037 are meaningful) have been observed. Nonselective T 1 measurements have been measured by recording four nonselective 180°-τ-NOESY at different τ values, and fitting the intensity recoveries to an exponential recovery. Thirty-six metal-proton upper and lower distance constraints have been obtained from the above measurements. The use of such constraints is assessed with respect to spin delocalization on the sulfur donor atoms. The solution structure obtained with the program DYANA has been refined through restrained energy minimization. A final family of 20 conformers is obtained with no distance violations larger than 0.24?Å, and RMSD values to the mean structure of 0.58 and 1.03?Å for backbone and all heavy atoms, respectively (measured on residues 3–53). The structure is compared to the X-ray structure of the oxidized and of the zinc substituted protein, and to the available structures of other rubredoxins. In particular, the comparison with the crystal structure and the solution structure of the Zn derivative of the highly thermostable Pyrococcus furiosus rubredoxin suggested that the relatively low thermal stability of the clostridial rubredoxin may be tentatively ascribed to the loosening of its secondary structure elements. This research is a further achievement at the frontier of solution structure determinations of paramagnetic proteins.  相似文献   
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The p25 coat protein (CP) gene of Citrustristezavirus (CTV) was incorporated to Mexican lime plants and forty-twotransgeniclines were produced, 25 containing the p25 CP gene of thesevere CTV strain T-305 and 17 with that of the mild strain T-317. When plantspropagated from each transgenic line were graft-inoculated with CTV T-305 oraphidinoculated with T-300, two types of response to viral challenge wereobserved: some lines developed CTV symptoms similar to those of non-transgeniccontrols, whereas others exhibited protection against the virus. Thisprotectionconsisted of a proportion of plants, ranging from 10 to 33%, that wereresistantto CTV, and the rest of them that showed a significant delay in virusaccumulation and symptom onset. Protection was efficient against non-homologousCTV strains and was generally accompanied by high accumulation of p25 CP in theprotected lines, which suggest a CP-mediated protection mechanism in mostcases.This is the first report demonstrating pathogen-derived resistance intransgenicplants against a Closterovirus member in its natural host.  相似文献   
135.
Biological Invasions - Introduced species can alter the dynamics and structure of a native community. Network analysis provides a tool to study host–parasite interactions that can help to...  相似文献   
136.
Recently developed proteomic technologies allow to profile thousands of proteins within a high-throughput approach towards biomarker discovery, although results are not as satisfactory as expected. In the present study we demonstrate that serum proteome denaturation is a key underestimated feature; in fact, a new differential denaturation protocol better discriminates serum proteins according to their electrophoretic mobility as compared to single-denaturation protocols. Sixty nine different denaturation treatments were tested and the 3 most discriminating ones were selected (TRIDENT analysis) and applied to human sera, showing a significant improvement of serum protein discrimination as confirmed by MALDI-TOF/MS and LC-MS/MS identification, depending on the type of denaturation applied. Thereafter sera from mice and patients carrying cutaneous melanoma were analyzed through TRIDENT. Nine and 8 protein bands were found differentially expressed in mice and human melanoma sera, compared to healthy controls (p<0.05); three of them were found, for the first time, significantly modulated: α2macroglobulin (down-regulated in melanoma, p<0.001), Apolipoprotein-E and Apolipoprotein-A1 (both up-regulated in melanoma, p<0.04), both in mice and humans. The modulation was confirmed by immunological methods. Other less abundant proteins (e.g. gelsolin) were found significantly modulated (p<0.05).Conclusions: i) serum proteome contains a large amount of information, still neglected, related to proteins folding; ii) a careful serum denaturation may significantly improve analytical procedures involving complex protein mixtures; iii) serum differential denaturation protocol highlights interesting proteomic differences between cancer and healthy sera.  相似文献   
137.
The current SARS-CoV-2 pandemic is wreaking havoc throughout the world and has rapidly become a global health emergency. A central question concerning COVID-19 is why some individuals become sick and others not. Many have pointed already at variation in risk factors between individuals. However, the variable outcome of SARS-CoV-2 infections may, at least in part, be due also to differences between the viral subspecies with which individuals are infected. A more pertinent question is how we are to overcome the current pandemic. A vaccine against SARS-CoV-2 would offer significant relief, although vaccine developers have warned that design, testing and production of vaccines may take a year if not longer. Vaccines are based on a handful of different designs (i), but the earliest vaccines were based on the live, attenuated virus. As has been the case for other viruses during earlier pandemics, SARS-CoV-2 will mutate and may naturally attenuate over time (ii). What makes the current pandemic unique is that, thanks to state-of-the-art nucleic acid sequencing technologies, we can follow in detail how SARS-CoV-2 evolves while it spreads. We argue that knowledge of naturally emerging attenuated SARS-CoV-2 variants across the globe should be of key interest in our fight against the pandemic.  相似文献   
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Applied Microbiology and Biotechnology - Herpes simplex virus type 1 (HSV-1) is responsible of common and widespread viral infections in humans through the world, and of rare, but extremely severe,...  相似文献   
140.
We investigate for the first time the influence of heart failure (HF) on nucleolar organization and proteins in patients with ischemic (ICM) or dilated cardiomyopathy (DCM). A total of 71 human hearts from ICM (n=38) and DCM (n=27) patients, undergoing heart transplantation and control donors (n=6), were analysed by western-blotting, RT-PCR and cell biology methods. When we compared protein levels according to HF etiology, nucleolin was increased in both ICM (117%, p<0.05) and DCM (141%, p<0.01). Moreover, mRNA expression were also upregulated in ICM (1.46-fold, p<0.05) and DCM (1.70-fold, p<0.05. Immunofluorescence studies showed that the highest intensity of nucleolin was into nucleolus (p<0.0001), and it was increased in pathological hearts (p<0.0001). Ultrastructure analysis by electron microscopy showed an increase in the nucleus and nucleolus size in ICM (17%, p<0.05 and 131%, p<0.001) and DCM (56%, p<0.01 and 69%, p<0.01). Nucleolar organization was influenced by HF irrespective of etiology, increasing fibrillar centers (p<0.001), perinucleolar chromatin (p<0.01) and dense fibrillar components (p<0.01). Finally, left ventricular function parameters were related with nucleolin levels in ischemic hearts (p<0.0001). The present study demonstrates that HF influences on morphology and organization of nucleolar components, revealing changes in the expression and in the levels of nucleolin protein.  相似文献   
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