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91.
Monkeypox infection outbreaks have been observed sporadically in Africa, usually as a result of interaction with wildlife reservoirs. The genomes of the new strain range in size from 184.7 to 198.0 kb and are identified with 143–214 open reading frames. Viral cores are rapidly carried on microtubules away from the cell's perimeter and deeper into the cytoplasm once the virus and cell membranes fuse. Depending on the kind of exposure, patients with monkeypox may experience a febrile prodrome 5–13 days after exposure, which frequently includes lymphadenopathy, malaise, headaches, and muscle aches. A different diagnostic approach is available for monkeypox, including histopathological analysis, electron microscopy, immunoassays, polymerase chain reaction, genome sequencing, microarrays, loop-mediated isothermal amplification technology and CRISPR (i.e., “clustered regularly interspaced short palindromic repeats”). There are currently no particular, clinically effective treatments available for the monkeypox virus. An initial treatment is cidofovir. As a monophosphate nucleotide analog, cidofovir is transformed into an inhibitor of viral DNA polymerase by cellular kinases, which is analogous to cidofovir's function in inhibiting viral DNA synthesis. The European Medicine Agency and the Food and Drug Administration have both granted permission for IMVAMUNE, a replication-deficient, attenuated third-generation modified vaccinia Ankara vaccine, to be used for the prevention of smallpox and monkeypox in adults.  相似文献   
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Big data processing, scientific calculations, and multimedia operations are some applications that require very complex time-consuming computations which cannot be performed on personal computers. Utilizing powerful cloud resources is a common method to address this problem. The amount of energy consumption of cloud data centers is an important challenge in these complex calculations, and reducing the energy consumption of cloud data centers is one of the most important goals of the researches in this area. The proposed method of this paper, called multi-agent deep Q-network with coral reefs optimization (MDQ-CR), combines the coral reefs optimization algorithm and multi-agent deep Q-network to reduce the energy consumption of data centers and cloud resources using the dynamic voltage and frequency scaling (DVFS) technique. The MDQ-CR has two main phases. The first phase exploits coral reefs optimization algorithm with a short-term view, and the second phase uses deep Q-network with a long-term view. The Markov game model is used to lead the learning agents to converge to the global optimal solution. Since processors consume the highest amount of energy of cloud compared to the other resources, the proposed method focuses on reducing the processors’ energy consumption. Reducing the voltage and frequency of processors, considering expiration times of their tasks, can reduce their energy consumption significantly. The empirical experiments show that the proposed method can save energy about 89% compared to completely randomized methods, and about 20% compared to the two recent methods of the literature.

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Abstract

The aim of this study was to investigate the spermine effect on the thermal denaturation, conformation and activity of elastase at three temperatures of 303, 313 and 323?K in the Tris buffer, at pH 8.5, using UV–vis spectrophotometry, spectrofluorometry and circular dichroism as well as molecular docking and molecular simulation. The increased absorption of elastase in the presence of spermine suggested a change in the environment of tryptophan. It was found that under the influence of spermine, the emission intensity of elastase extremely was reduced, and the use of the Stern-Volmer equation showed that some static quenching had occurred. The thermodynamic parameters values (enthalpy and entropy) and the molecular docking technique also revealed that van der Waals forces or hydrogen bonding interactions played an important role in the binding process. The spermine–elastase complex formation led to increasing the value of the catalytic constant (kcat). So it could be considered as an activator. Slight changes were observed in the second structure of elastase (1.06% increase for the α-helix and 0.048% decrease the β-sheet) and the thermal stability effect. Molecular docking results also demonstrated that spermine could bind to porcine pancreatic elastase, and van der Waals forces or hydrogen bonding interactions played the major role in the binding process. Overall, our results showed that spermine could induce structural alterations in elastase, acting as a partial stabilizer and an activator for the enzyme.

Communicated by Ramaswamy H. Sarma  相似文献   
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Introduction& Objectives: Redox signaling is a critical regulator in the process of wound healing. This signaling pathway can be effective in the development or healing of diabetic ulcers through the ECM.In this study, the structure of extracellular matrix investigated in relation to redox signaling in the tissue of patients with diabetic ulcers that lead to organ amputation.Materials and methodsThe case-control design on diabetic patients ulcers as case group and non-diabetic limb ischemia as control were used.Hematoxylin-eosin, trichrome, and elastin staining methods were used for pathological evaluations of ECM. MDA, total thiol, and SOD levels were measured using ELISA kits to assess the oxidative stress level. Also, NO level was measured by using ELISA kits in both groups. Expression levels of genes MMP2, MMP9, and HIF were detected using real-time PCR with SYBR-green assay.ResultsThe pathological results showed an increase in the thickness of collagen and elastin fibers. Lipids atrophy was visible in the tissue isolated from the diabetic wound group. The amount of MAD to evaluate the level of lipid oxidation in patients with diabetic Ulcer was significantly higher than the control group(p < 0.01). Thiol level was significantly lower in the diabetic ulcer group than in the control group(p < 0.0001). The expression of metalloproteinases 2 and 9 genes in the tissues isolated from diabetic ulcers was lower than the control group(p < 0.0001). While the expression of the HIF gene in this group was higher than the control group(p < 0.0001).ConclutionIn the diabetic wound, the HIF secretion due to hypoxic conditions is beneficial for matrix deposition and prevents protease activity, but if the hypoxia persists, it can lead to ECM deposition subsequently increases the tissue pressure, increases of the collagen I-to-collagen III ratio in collagen accumulation that due to more hypoxia , lipidsAtrophy and eventually amputation.  相似文献   
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A systematic computational study is carried out to investigate hydrogen bond (HB) interactions in the real crystalline structures of l-Cysteine at 30 and 298 K by density functional theory (DFT) calculations of electric field gradient (EFG) tensors at the sites of O-17, N-14, and H-2 nuclei. One-molecule (monomer) and nine-molecule (cluster) models of l-Cysteine are created by available crystal coordinates at both temperatures and the EFG tensors are calculated for both models to indicate the effect of HB interactions on the tensors. The calculated EFG tensors at the level of B3LYP and B3PW91 DFT methods and 6-311++G?? and cc-pVTZ basis sets are converted to those experimentally measurable nuclear quadrupole resonance (NQR) parameters i.e. quadrupole coupling constants (qcc) and asymmetry parameters (ηQ). The evaluated NQR parameters reveal that the EFG tensors of 17O, 14N, and 2H are influenced and show particular trends from monomer to the target molecule in the cluster due to the contribution of target molecule to classic N–H…O, and non-classic S–H…O and S–H…S types of HB interactions. On the other hand, atoms in molecules (AIM) analyses confirm the presence of HB interactions and rationalize the observed EFG trends. The results indicate different contribution of various nuclei to HB interactions in the cluster where O2 and N1 have major contributions. The EFG tensors as well as AIM analysis at the H6 site show that the N1-H6…O2 HB undergoes a significant change from 30 to 298 K where changes in other N–H…O interactions are almost negligible. There is a good agreement between the calculated 14N NQR parameters and reported experimental data.  相似文献   
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