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201.
The goal of this work is to study the influence of different curing systems on the cure characteristics and performance of styrene–butadiene elastomer (SBR) filled with carbon black or nanosized silica. A multifunctional additive for rubber compounds, namely Activ8, was applied as an additional activator and accelerator to increase the efficiency of sulfur vulcanization and to reduce the content of zinc oxide elastomers cured in the presence of 2-mercaptobenzothizole or 1,3-diphenylguanidine as a primary accelerator. The influence of the curing system composition on the crosslink density and physical properties of SBR vulcanizates, such as mechanical properties, thermal stability, and resistance to thermo-oxidative aging, is also reported. Activ8 effectively supports the vulcanization of SBR compounds, especially filled with nanosized silica. It reduces the optimal vulcanization time of SBR compounds and increases the crosslink density of the vulcanizates. Moreover, vulcanizates with Activ8 exhibit higher tensile strength and better damping properties than elastomer with zinc oxide. Activ8 allows the amount of ZnO to be reduced by 40% without detrimental effects on the crosslink density and mechanical performance compared to the vulcanizates conventionally crosslinked with ZnO. This is an important ecological goal since ZnO is classified as being toxic to aquatic species. 相似文献
202.
Jacek Baj Izabela Korona-Gowniak Grzegorz Buszewicz Alicja Forma Monika Sitarz Grzegorz Teresiski 《Viruses》2020,12(11)
Infections that are triggered by the accompanying immunosuppression in patients with burn wounds are very common regardless of age. Among burn patients, the most frequently diagnosed infections include the bacterial ones primarily caused by Pseudomonas aeruginosa or Klebsiella pneumonia, as well as fungal infections with the etiology of Candida spp. or Aspergillus spp. Besides, burn wounds are highly susceptible to viral infections mainly due to the impaired immune responses and defective functions of the immune cells within the wound microenvironment. The most prevalent viruses that invade burn wounds include herpes simplex virus (HSV), cytomegalovirus (CMV), human papilloma virus (HPV), and varicella zoster virus (VZV). Likewise, less prevalent infections such as those caused by the orf virus or Epstein–Barr Virus (EBV) might also occur in immunosuppressed burn patients. Viral infections result in increased morbidity and mortality rates in severely burned patients. Additionally, a positive correlation between the hospitalization duration and the severity of the viral infection has been demonstrated. Viral infections trigger the occurrence of various complications, ranging from mild symptoms to even fatal incidents. Accurate detection of viral infection is of great clinical importance because of the possibility for a quicker introduction of proper treatment therapy and shortening of hospitalization time. The aim of this paper is to provide a comprehensive review of the literature and summarize the findings regarding the most common viral infections in immunosuppressed burn patients. 相似文献
203.
Krzysztof Tomczuk Krzysztof Kostro Klaudiusz Oktawian Szczepaniak Maciej Grzybek Maria Studzińska Marta Demkowska-Kutrzepa Monika Roczeń-Karczmarz 《Parasitology research》2014,113(6):2401-2406
The autopsy of 487 slaughter horses revealed the presence of Anoplocephala perfoliata in 36 animals. The invasions varied in the intensity (3 to 2,069 tapeworms) and in the level of tapeworms’ proglottid maturity. Twenty nine horses were found to contain tapeworms with gravid proglottid. Fecal samples collected from the rectum were tested using following techniques: flotation with solution-saturated NaCl, decantation, McMaster’s, and modified sedimentation-flotation methods (50 g feces samples, flotation solution-saturated NaCl and sucrose, specific gravity 1.25 g/ml). The number of A. perfoliata positive fecal samples was significantly higher using the sedimentation-flotation methods 21 (58.33 %) than flotation 6 (16.66 %), decantation 3 (8.33 %), and McMaster’s 1 (2.77 %) techniques. The sensitivities of the coprological methods during the patent period were 20.69, 10.34, 3.45, and 72.41 % for the flotation, decantation, McMaster’s, and sedimentation-flotation method, respectively. Sedimentation–flotation techniques proved to be more sensitive than other one. The lowest intensity of invasion possible to detect using this method was nine tapeworms with gravid proglottid. 相似文献
204.
Jonas Pick Aditya Arra Holger Lingel J. Kolja Hegel Magdalena Huber Gopala Nishanth Gerhard Jorch Klaus‐Dieter Fischer Dirk Schlüter Kerry Tedford Monika C. Brunner‐Weinzierl 《European journal of immunology》2014,44(7):2139-2152
Although CD8+ T cells that produce IL‐17 (Tc17 cells) have been linked to host defense, Tc17 cells show reduced cytotoxic activity, which is the characteristic function of CD8+ T cells. Here, we show that CTLA‐4 enhances the frequency of IL‐17 in CD8+ T cells, indicating that CTLA‐4 (CD152) specifically promotes Tc17 differentiation. Simultaneous stimulation of CTLA‐4+/+ and CTLA‐4?/? T cells in cocultures and agonistic CTLA‐4 stimulation unambiguously revealed a cell‐intrinsic mechanism for IL‐17 control by CTLA‐4. The quality of CTLA‐4‐induced Tc17 cells was tested in vivo, utilizing infection with the facultative intracellular bacterium Listeria monocytogenes (LM). Unlike CTLA‐4+/+ Tc17 cells, CTLA‐4?/? were nearly as efficient as Tc1 CTLA‐4+/+ cells in LM clearance. Additionally, adoptively transferred CTLA‐4?/? Tc17 cells expressed granzyme B after rechallenge, and produced Tc1 cytokines such as IFN‐γ and TNF‐α, which strongly correlate with bacterial clearance. CTLA‐4+/+ Tc17 cells demonstrated a high‐quality Tc17 differentiation program ex vivo, which was also evident in isolated IL‐17‐secreting Tc17 cells, with CTLA‐4‐mediated enhanced upregulation of Tc17‐related molecules such as IL‐17A, RORγt, and IRF‐4. Our results show that CTLA‐4 promotes Tc17 differentiation that results in robust Tc17 responses. Its inactivation might therefore represent a central therapeutic target to enhance clearance of infection. 相似文献
205.
The Implicit Association Test (IAT) is a widely used latency‐based categorization task that indirectly measures the strength of automatic associations between target and attribute concepts. So far, little is known about the perceptual and cognitive processes underlying personality IATs. Thus, the present study examined event‐related potential indices during the execution of an IAT measuring neuroticism (N = 70). The IAT effect was strongly modulated by the P1 component indicating early facilitation of relevant visual input and by a P3b‐like late positive component reflecting the efficacy of stimulus categorization. Both components covaried, and larger amplitudes led to faster responses. The results suggest a relationship between early perceptual and semantic processes operating at a more automatic, implicit level and later decision‐related categorization of self‐relevant stimuli contributing to the IAT effect. 相似文献
206.
Andrea Kucharíková Andrea Schreiberová Monika Závodská Štefánia Gedrová Ľudmila Hricová Jaroslav Pavel Ján Gálik Martin Maršala Nadežda Lukáčová 《Acta histochemica》2014
The interruption of supraspinal input to the spinal cord leads to motor dysfunction and the development of spasticity. Clinical studies have shown that Baclofen (a GABAB agonist), while effective in modulating spasticity is associated with side-effects and the development of tolerance. The aim of the present study was to assess if discontinued Baclofen treatment and its repeated application leads antispasticity effects, and whether such changes affect neuronal nitric oxide synthase (nNOS) in the brainstem, nNOS and parvalbumin (PV) in lumbar α-motoneurons and glial fibrillary acidic protein in the ventral horn of the spinal cord. Adult male Wistar rats were exposed to Th9 spinal cord transection. Baclofen (30 mg/b.w.) diluted in drinking water, was administered for 6 days, starting at week 1 after injury and then repeated till week 4 after injury. The behavior of the animals was tested (tail-flick test, BBB locomotor score) from 1 to 8 weeks. Our results clearly indicate the role of nitric oxide, produced by nNOS in the initiation and the maintenance of spasticity states 1, 6 and 8 weeks after spinal trauma. A considerable decrease of nNOS staining after Baclofen treatment correlates with improvement of motor dysfunction. The findings also show that parvalbumin and astrocytes participate in the regulation of ion concentrations in the sub-acute phase after the injury. 相似文献
207.
Variants in the ATM‐CHEK2‐BRCA1 axis determine genetic predisposition and clinical presentation of papillary thyroid carcinoma
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Anna Wójcicka Małgorzata Czetwertyńska Michał Świerniak Joanna Długosińska Monika Maciąg Agnieszka Czajka Kinga Dymecka Anna Kubiak Adam Kot Rafał Płoski Albert de la Chapelle Krystian Jażdżewski 《Genes, chromosomes & cancer》2014,53(6):516-523
The risk of developing papillary thyroid carcinoma (PTC), the most frequent form of thyroid malignancy, is elevated up to 8.6‐fold in first‐degree relatives of PTC patients. The familial risk could be explained by high‐penetrance mutations in yet unidentified genes, or polygenic action of low‐penetrance alleles. Since the DNA‐damaging exposure to ionizing radiation is a known risk factor for thyroid cancer, polymorphisms in DNA repair genes are likely to affect this risk. In a search for low‐penetrance susceptibility alleles we employed Sequenom technology to genotype deleterious polymorphisms in ATM, CHEK2, and BRCA1 in 1,781 PTC patients and 2,081 healthy controls. As a result of the study, we identified CHEK2 rs17879961 (OR = 2.2, P = 2.37e‐10) and BRCA1 rs16941 (odds ratio [OR] = 1.16, P = 0.005) as risk alleles for PTC. The ATM rs1801516 variant modifies the risk associated with the BRCA1 variant by 0.78 (P = 0.02). Both the ATM and BRCA1 variants modify the impact of male gender on clinical variables: T status (P = 0.007), N status (P = 0.05), and stage (P = 0.035). Our findings implicate an important role of variants in the ATM‐ CHEK2‐ BRCA1 axis in modification of the genetic predisposition to PTC and its clinical manifestations. © 2014 Wiley Periodicals, Inc. 相似文献
208.
Agnieszka Zagrska Anna Partyka Adam Bucki Marcin Koaczkowski Magdalena Jastrzbska‐Wisek Anna Czopek Agata Siwek Monika Guch‐Lutwin Marek Bednarski Marek Bajda Jakub Joczyk Kamil Piska Paulina Koczurkiewicz Anna Wesoowska Maciej Pawowski 《Chemical biology & drug design》2019,93(4):511-521
A series of 2‐pyrimidinyl‐piperazinyl‐alkyl derivatives of 1H‐imidazo[2,1‐f]purine‐2,4(3H,8H)‐dione has been synthesized in an attempt to discover a new class of psychotropic agents. Compounds were evaluated for their in vitro affinity for serotonin 5‐HT1A, 5‐HT7, and phosphodiesterases PDE4 and PDE10. The most potent compound 2‐pyrimidinyl‐1‐piperazinyl‐butyl‐imidazo[2,1‐f]purine‐2,4‐dione ( 4b ) behaved as strong and selective antagonist of 5‐HT1A. Molecular modeling studies revealed differences in binding mode between compound 4b and buspirone, which might reflect variation of the ligands’ affinity and potency in the 5‐HT1A receptor. Compound 4b in silico models demonstrated drug‐likeness properties and, contrary to buspirone, showed a metabolic stability in mouse liver microsomes system. Experimentally obtained value of apparent permeability coefficient Papp for 4b in parallel artificial permeability assay indicates the possibility of binding weakly to plasma proteins and high intestinal absorption fraction. Evaluation of the antidepressant‐ and anxiolytic‐like activities of 4b revealed both activities at the same dose of 1.25 mg/kg and seemed to be specific. The antidepressant and/or anxiolytic properties of 4b may be related to its first‐pass effect. 相似文献
209.
Aashish Contractor Bidyut K. Sarkar Monika Arora Kiran Saluja 《Current cardiovascular risk reports》2014,8(11):1-9
The global epidemic of cardiovascular diseases (CVDs) is spiraling upwards primarily due to a sharp rise in the low and middle income countries (LMICs) which are experiencing rapid health transition driven by socioeconomic, technological and lifestyle changes. LMICs currently face a double burden of communicable and non-communicable diseases, leading to competing claims of health conditions that vie for policy makers’ attention as public health priorities in a setting of limited resources, substantially high out-of-pocket expenditure and weak systems of healthcare delivery. Evidence from high income countries suggests that most CVDs are largely preventable as the major CVD risk behaviours including tobacco use, physical inactivity, unhealthy diet, harmful use of alcohol, are avoidable and modifiable. Effective and sustainable behaviour change strategies for LMICs would require low cost, affordable and scalable interventions. There is limited evidence from LMICs on effective interventions to prevent, control and manage CVDs in LMICs. The global guidelines and framework for addressing CVD calls for an urgent need to identify and assess contextually relevant and resource sensitive health care interventions augmented by policy actions. A combination of population based and high risk individual based strategies which are evidence based, cost-effective, feasible as well as scalable would reduce CVD mortality and its devastating impact in LMICs. 相似文献
210.
Vivek K.Bajpai Jung In Yoon Monika Bhardwaj Sun Chul Kang 《Asian Pacific journal of tropical medicine》2014,7(8):602-608
Objective:To examine the individual and synergistic anti-listcrial effect of nisin and leaf essential oil of Metasequoia glyptostroboides(M.glyptostroboides) against one of the leading foodhorne pathogens Listeria monocytogenes(L.monocytogenes) ATCC 19116 in milk samples.Methods:The whole(8%),low(1%) and skim(no fat content) milk samples were inoculated with L.monocytogenes ATCC 19116 along with leaf essential oil of M.glyptostroboides or nisin alone as well in eomhinations.Results:In this study,the leaf essential oil at the concentrations of 2% and 5% revealed strong anti-listerial effect against L.monocytogenes ATCC 19116 in all categories of milk samples.Nisin at the concentrations of 250 and 500 IU/mL displayed a strong inhibitory effect against ATCC 19116 as compared to the control group.Additionally,synergistic combinations of leaf essential oil(1%) and nisin(62.5,125.250 and 500 IU/mL) also had a remarkable anti-listerial synergism in all the tested milk samples including whole,low and skim milk after 14 days.Conclusions:As a major finding,the leaf essential oil of M.glyptostroboides might he a useful candidate for using in food industry to control the growth of foodhorne pathogenic bacteria as confirmed by its potent anti-listerial Synergistic effect with nisin against L.monocytogenes ATCC 19116 in different milk samples. 相似文献