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61.
Our earlier findings revealed that interleukin-1 receptor type-1 (IL-1R1) was overexpressed in spinal neurons, and IL-1R1-deficient mice showed significant attenuation of thermal and mechanical allodynia during the course of the Complete Freund adjuvant (CFA)-induced persistent pain model. In the present study, we found that a ligand of IL-1R1, termed interleukin-1β (IL-1β), is also significantly overexpressed at the peak of mechanical pain sensitivity in the CFA-evoked pain model. Analysis of cellular distribution and modeling using IMARIS software showed that in the lumbar spinal dorsal horn, IL-1β is significantly elevated by astrocytic expression. Maturation of IL-1β to its active form is facilitated by the formation of the multiprotein complex called inflammasome; thus, we tested the expression of NOD-like receptor proteins (NLRPs) in astrocytes. At the peak of mechanical allodynia, we found expression of the NLRP2 inflammasome sensor and its significantly elevated co-localization with the GFAP astrocytic marker, while NLRP3 was moderately present and NLRP1 showed total segregation from the astrocytic profiles. Our results indicate that peripheral CFA injection induces NLRP2 inflammasome and IL-1β expression in spinal astrocytes. The release of mature IL-1β can contribute to the maintenance of persistent pain by acting on its neuronally expressed receptor, which can lead to altered neuronal excitability.  相似文献   
62.
63.
Spreading depolarization (SD) is a wave of mass depolarization that causes profound perfusion changes in acute cerebrovascular diseases. Although the astrocyte response is secondary to the neuronal depolarization with SD, it remains to be explored how glial activity is altered after the passage of SD. Here, we describe post-SD high frequency astrocyte Ca2+ oscillations in the mouse somatosensory cortex. The intracellular Ca2+ changes of SR101 labeled astrocytes and the SD-related arteriole diameter variations were simultaneously visualized by multiphoton microscopy in anesthetized mice. Post-SD astrocyte Ca2+ oscillations were identified as Ca2+ events non-synchronized among astrocytes in the field of view. Ca2+ oscillations occurred minutes after the Ca2+ wave of SD. Furthermore, fewer astrocytes were involved in Ca2+ oscillations at a given time, compared to Ca2+ waves, engaging all astrocytes in the field of view simultaneously. Finally, our data confirm that astrocyte Ca2+ waves coincide with arteriolar constriction, while post-SD Ca2+ oscillations occur with the peak of the SD-related vasodilation. This is the first in vivo study to present the post-SD astrocyte Ca2+ oscillations. Our results provide novel insight into the spatio-temporal correlation between glial reactivity and cerebral arteriole diameter changes behind the SD wavefront.  相似文献   
64.
Cardioprotective medications are still unmet clinical needs. We have previously identified several cardioprotective microRNAs (termed ProtectomiRs), the mRNA targets of which may reveal new drug targets for cardioprotection. Here we aimed to identify key molecular targets of ProtectomiRs and confirm their association with cardioprotection in a translational pig model of acute myocardial infarction (AMI). By using a network theoretical approach, we identified 882 potential target genes of 18 previously identified protectomiRs. The Rictor gene was the most central and it was ranked first in the protectomiR-target mRNA molecular network with the highest node degree of 5. Therefore, Rictor and its targeting microRNAs were further validated in heart samples obtained from a translational pig model of AMI and cardioprotection induced by pre- or postconditioning. Three out of five Rictor-targeting pig homologue of rat ProtectomiRs showed significant upregulation in postconditioned but not in preconditioned pig hearts. Rictor was downregulated at the mRNA and protein level in ischemic postconditioning but not in ischemic preconditioning. This is the first demonstration that Rictor is the central molecular target of ProtectomiRs and that decreased Rictor expression may regulate ischemic postconditioning-, but not preconditioning-induced acute cardioprotection. We conclude that Rictor is a potential novel drug target for acute cardioprotection.  相似文献   
65.
Prevention of fungal spoilage is a key microbiological issue for the shelf life of fat spreads. Our aim was to assess and model the scope of (natural) antimicrobials for extending shelf life of spreads (water-in-oil emulsions). Production conditions were established to make 60% model fat spreads with reproducible droplet size distributions. The mould vulnerabilities ranged from 1 to 20 weeks. The system allowed feasibility testing of lytic enzymes (Novozym 234) and LMW compounds against Penicillium roqueforti, a key-spoilage mould. The action of Novozym 234, carvacrol, undecanol and dihydrocarveol was benchmarked against sorbate and preservative-free controls under ambient and chilled conditions. Novozym 234 was ineffective to prevent outgrowth of P. roqueforti. Carvacrol, undecanol and dihydrocarveol had limited effects on shelf-life extension compared to sorbate. Fungal growth boundaries of (un-)preserved spreads were modelled. The emulsion droplet size distribution (DSD) was first captured in a mechanistic parameter DSD-I (I = Influence). DSD-I was a move away from the mean droplet diameter D3,3 as sole quantitative droplet-size distribution parameter for mould susceptibility of emulsions. DSD-I is a combination of available water droplets and surface area to initiate and sustain fungal outgrowth. Followup experiments showed that modelling D3,3 and distribution width (e(sigma)) instead of DSD-I gave better results for emulsions with high e(sigma). Empirical predictive models were subsequently developed for the effects of D3,3, e(sigma) and undissociated sorbic acid (HSO) on the shelf life of emulsions.  相似文献   
66.
This paper addresses a study of gas–oil gravity drainage in fractured carbonate rock subjected to gas injection in low interfacial tension. The purpose of the experiments described in the paper was to investigate gas injection in fractured carbonate reservoirs in both secondary and tertiary cases (after water injection), focusing on gravity drainage using equilibrium gas followed by re-pressurization. Gas injection experiments were performed on 20 cm long and low permeable outcrop chalk core surrounded with a fracture established with a novel experimental set-up in reservoir conditions. The core was saturated with binary mixture live oil consisting of C1 and C7 of a known composition, while the fracture was filled with sealing material to obtain a homogeneous saturation. After core initialization, the sealing material was removed by increasing the temperature to higher than its melting point and displaced by live oil. Gas was then injected into the fracture and gravity drainage experiments were performed in low interfacial tension (< 0.5 mN/m) where the IFT between the phases were measured experimentally by selecting the proper pressure and temperature.Experiments were performed at different pressures and reversibility of the effect of the interfacial tension was checked by re-pressurization process. The oil recovered from the bottom side of the block was measured versus time.Based on the results of this study, the recovery of oil showed a significant increase by re-pressurization in gravity drainage process. It was also clear that low IFT gravity drainage is capable to recover a significant amount of oil in fractured reservoirs even after water injection.  相似文献   
67.
In this study, we provide the first genetically verified distribution record beyond its native range of Ligula pavlovskii, a high-impact endoparasite of Ponto-Caspian gobies. According to parasitological surveys, ligulosis was detected for the first time in monkey goby individuals collected from Lake Balaton in 2004, 34 years after the first record of monkey goby in the lake. During a Lake Balaton survey in 2018, we detected tapeworms in 44.4% of the sampled monkey gobies. This prevalence is about two to ten times higher than it was reported from within the native range of the fish hosts. The same survey revealed an uneven spatial distribution of the ligulosis in the monkey gobies inhabiting different shoreline sections of the lake. We assume that the occurrence and recent distribution data of this high-impact endoparasite may provide useful information for potential biocontrol measures of invasive Ponto-Caspian gobies in the future.  相似文献   
68.
The present state of the development and production of Russian and foreign radio-measuring instruments in the frequency range up to 178.4 GHz (and higher) and the proposed glossary of the new generation of Russian instruments are considered.  相似文献   
69.
Diamond coatings were deposited by hot filament chemical vapor deposition on high speed steel substrates. Iron boride diffusion barrier and WC–Co layers were used as interlayers. At high deposition pressure, the quality of the diamond deposits is poor due to the extensive formation of graphitic deposits. At low pressure, diamond films of better quality were obtained, but their adhesion to the substrate was insufficient. A two-step deposition process at low pressure was developed. In a first deposition step performed at high methane percentage, a high nucleation density was achieved. In a second deposition step, the methane percentage was reduced to achieve continuous, dense, and adherent diamond layers on borided or WC–Co coated high speed steel substrates. Adhesion of these diamond layers on the surface modified high speed steel substrates was tested based on reciprocating sliding tests.  相似文献   
70.
Vaginismus is commonly described as a persistent difficulty in allowing vaginal entry of a penis or other object. Lifelong vaginismus occurs when a woman has never been able to have intercourse. A replicated single-case A-B-phase design was used to investigate the effectiveness of therapist-aided exposure for lifelong vaginismus. A baseline period (Phase A) was contrasted with exposure + follow-up (Phase B), using random switching between phases. The main outcome measure (intercourse ability) was assessed daily for 24 weeks. Ten women participated. The exposure consisted of a maximum of three 2-hr sessions during 1 week at a university hospital. The participant performed vaginal penetration exercises on herself, in the presence of a female therapist. Two follow-up sessions were scheduled over a 5-week period. Nine of the 10 participants reported having intercourse after treatment, and in 5 of the 9, intercourse was possible within the 1st week of treatment. The results remained at 1-year follow-up. Furthermore, exposure was successful in decreasing fear and negative penetration beliefs posttreatment and at 3-month and 1-year follow-ups. Therapist-aided exposure appears to be an effective treatment for lifelong vaginismus. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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