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71.
Aim of this trial was to verify the residues of two fungicides, already authorised for the use in field (the admitted maximum limit of residues have been fixed), after post harvest treatments on pears and apples for defence against main post harvest rots. The use of formulation in post harvest must consider also the technique of product application. In fact there are different systems to carry out the treatments for the protection of the commodities during cold storage. In this trial two formulations of pyrimethanil and imazalil were applied by drencher on pome fruit.  相似文献   
72.

Background

MNEI and its variant Y65R-MNEI are sweet proteins with potential applications as sweeteners in food industry. Also, they are often used as model systems for folding and aggregation studies.

Methods

X-ray crystallography was used to structurally characterize Y65R-MNEI at five different pHs, while circular dichroism and fluorescence spectroscopy were used to study their thermal and chemical stability. ThT assay and AFM were used for studying the kinetics of aggregation and morphology of the aggregates.

Results

Crystal structures of Y65R-MNEI revealed the existence of a dimer in the asymmetric unit, which, depending on the pH, assumes either an open or a closed conformation. The pH dramatically affects kinetics of formation and morphology of the aggregates: both MNEI and Y65R-MNEI form fibrils at acidic pH while amorphous aggregates are observed at neutral pH.

Conclusions

The mutation Y65R induces structural modifications at the C-terminal region of the protein, which account for the decreased stability of the mutant when compared to MNEI. Furthermore, the pH-dependent conformation of the Y65R-MNEI dimer may explain the different type of aggregates formed as a function of pH.

General significance

The investigation of the structural bases of aggregation gets us closer to the possibility of controlling such process, either by tuning the physicochemical environmental parameters or by site directed mutagenesis. This knowledge is helpful to expand the range of stability of proteins with potential industrial applications, such as MNEI and its mutant Y65R-MNEI, which should ideally preserve their structure and soluble state through a wide array of conditions.  相似文献   
73.

Background

According to the World Health Organization, air pollution is closely associated with climate change and, in particular, with global warming. In addition to melting of ice and snow, rising sea level, and flooding of coastal areas, global warming is leading to a tropicalization of temperate marine ecosystems. Moreover, the effects of air pollution on airway and lung diseases are well documented as reported by the World Allergy Organization.

Methods

Scientific literature was searched for studies investigating the effect of the interaction between air pollution and climate change on allergic and respiratory diseases.

Results

Since 1990s, a multitude of articles and reviews have been published on this topic, with many studies confirming that the warming of our planet is caused by the “greenhouse effect” as a result of increased emission of “greenhouse” gases. Air pollution is also closely linked to global warming: the emission of hydrocarbon combustion products leads to increased concentrations of biological allergens such as pollens, generating a mixture of these particles called particulate matter (PM). The concept is that global warming is linked to the emission of hydrocarbon combustion products, since both carbon dioxide and heat increase pollen emission into the atmosphere, and all these particles make up PM10. However, the understanding of the mechanisms by which PM affects human health is still limited. Therefore, several studies are trying to determine the causes of global warming. There is also evidence that increased concentrations of air pollutants and pollens can activate inflammatory mediators in the airways. Our Task Force has prepared a Decalogue of rules addressing public administrators, which aims to limit the amount of allergenic pollen in the air without sacrificing public green areas.

Conclusions

Several studies underscore the significant risks of global warming on human health due to increasing levels of air pollution. The impact of climate change on respiratory diseases appears well documented. The last decades have seen a rise in the concentrations of pollens and pollutants in the air. This rise parallels the increase in the number of people presenting with allergic symptoms (e.g., allergic rhinitis, conjunctivitis, and asthma), who often require emergency medical care. Our hope is that scientists from different disciplines will work together with institutions, pharmaceutical companies and lay organizations to limit the adverse health effects of air pollution and global warming.
  相似文献   
74.
We have previously shown that the development of type 1 diabetes (T1D) can be prevented in nonobese diabetic (NOD) mice by reconstitution with autologous hemopoietic stem cells retrovirally transduced with viruses encoding MHC class II I-A beta-chain molecules associated with protection from the disease. In this study we examined whether a blockade of the programmed death-1 (PD-1)-programmed death ligand-1 (PD-L1) pathway, a major pathway known to control diabetes occurrence, could precipitate T1D in young NOD mice following reconstitution with autologous bone marrow retrovirally transduced with viruses encoding protective MHC class II I-A beta-chain molecules. In addition, we examined whether the expression of protective MHC class II alleles in hemopoietic cells could be used to prevent the recurrence of diabetes in mice with pre-existing disease following islet transplantation. Protection from the occurrence of T1D diabetes in young NOD mice by the expression of protective MHC class II I-A beta-chain molecules in bone marrow-derived hemopoietic cells was resistant to induction by PD-1-PD-L1 blockade. Moreover, reconstitution of NOD mice with pre-existing T1D autologous hemopoietic stem cells transduced with viruses encoding protective MHC class II I-A beta-chains allowed for the successful transplantation of syngeneic islets, resulting in the long-term reversal of T1D. Reversal of diabetes was resistant to induction by PD-1-PDL-1 blockade and depletion of CD25(+) T cells. These data suggest that expression of protective MHC class II alleles in bone marrow-derived cells establishes robust self-tolerance to islet autoantigens and is sufficient to prevent the recurrence of autoimmune diabetes following islet transplantation.  相似文献   
75.
Aim of this trial was to verify the occurrence and the distribution of organochlorine pesticides (OCPs) in soil, uptake and translocation by different crops growing in glasshouses with different level of pollutants. Residues of OCPs have been detected in soils and crops in the province of Latina, an intensively agricultural area of Lazio Region, in Italy. Dieldrin was quantified particularly in zucchini, cucumber, melon, tomato during a vegetation period. Sampling was carried out at three different times after transplanting. Roots, stem, Leaves and fruits were analysed separately. It would not be advisable to grow cucurbits in soil with OCPs residues > 0.100 mg/kg, to respect the RML admitted in UE in cucurbitaceous fruits.  相似文献   
76.
Several studies have focused their attention on increasing the production of lactobacillus ssp. (LAB) biomass via‐fermentation, in particular exploiting novel in situ product removal bioreactors that prevent accumulation of lactic acid, and therefore growth inhibition. Lactobacillus plantarum is one of the most studied species, used in nutritional supplements and in food processing. This research aimed to obtain high cell densities of L. plantarum, through fed‐batch and microfiltration experiments. The latter achieved a 5‐fold higher biomass density compared with batch experiments. Furthermore, the L. plantarum strain, isolated from Portoguese chorizo, was characterized for its ability to survive simulated digestion in vitro and competition potential toward certain common pathogens. Finally, the possibility of exploiting dairy liquid wastes (whey) as medium components was also explored demonstrating the strain's capability of metabolizing bovine‐ovine whey. This finding might be relevant in liquid waste treatments of diary industries that are well distributed in our region. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:325–333, 2015  相似文献   
77.
Human Cytomegalovirus (HCMV) is a major cause of morbidity and mortality in transplant patients and in fetuses following congenital infection. The glycoprotein complexes gH/gL/gO and gH/gL/UL128/UL130/UL131A (Pentamer) are required for HCMV entry in fibroblasts and endothelial/epithelial cells, respectively, and are targeted by potently neutralizing antibodies in the infected host. Using purified soluble forms of gH/gL/gO and Pentamer as well as a panel of naturally elicited human monoclonal antibodies, we determined the location of key neutralizing epitopes on the gH/gL/gO and Pentamer surfaces. Mass Spectrometry (MS) coupled to Chemical Crosslinking or to Hydrogen Deuterium Exchange was used to define residues that are either in proximity or part of neutralizing epitopes on the glycoprotein complexes. We also determined the molecular architecture of the gH/gL/gO- and Pentamer-antibody complexes by Electron Microscopy (EM) and 3D reconstructions. The EM analysis revealed that the Pentamer specific neutralizing antibodies bind to two opposite surfaces of the complex, suggesting that they may neutralize infection by different mechanisms. Together, our data identify the location of neutralizing antibodies binding sites on the gH/gL/gO and Pentamer complexes and provide a framework for the development of antibodies and vaccines against HCMV.  相似文献   
78.
Bilastine is a new second generation H1-antihistamine recently approved for the symptomatic treatment of allergic rhinitis (AR) and chronic urticaria (CU). Bilastine epitomizes the evolution of research on antihistamines concerning both efficacy and safety. In AR treatment, a number of large controlled clinical trials documented its efficacy, as assessed by improvement of all nasal and ocular symptoms and quality of life. These outcomes show that bilastine meets current EAACI/ARIA criteria for medications used in the treatment of AR. Also in CU, the review of the literature indicates that once-daily treatment with bilastine 20 mg was effective in managing symptoms and improving patient’s quality of life. Concerning safety and tolerability, the profile of bilastine is very similar to placebo and in particular the adverse effects on central nervous system are insignificant. The balance of efficacy and safety of bilastine is particularly helpful when dosages higher than standard are needed to control the symptoms, as frequently occurs in patients with urticaria, in whom antihistamines doses up to four times the standard dose may be administered.  相似文献   
79.
The growing interest in the substitution of ‘synthetic pesticides’ by natural ones has fostered the research on vegetable sources and the screening of plant materials to identify new compounds. The aim of this study was to evaluate the efficacy of several essential oils used alone and alternating with a synthetic fungicide. Experimental trials were carried out in greenhouse during the years 2012–2013 testing four alternative application programmes. Chemical composition of the essential oils and evaluation of their residues on treated zucchini leaves were reported by a gas chromatography–mass spectrometry (GC/MS) analysis. Moreover, relative density analyses were carried out. The obtained results showed that the alternation of essential oils and synthetic chemicals can maintain a disease control, resulting that an integrated control management of zucchini powdery mildew is able to reduce the use of synthetic fungicides.  相似文献   
80.
Carotid artery stenosis (CS) is a well-established risk factor for stroke. Increased proinflammatory chemokines, enhanced metallothionein (MT), and altered metal homeostasis may play roles in atherosclerosis progression and plaque destabilization. MT may sequester zinc during chronic inflammation, provoke zinc deficiency, and modulate NK cell cytotoxicity. A recent investigation of older patients with diabetes and atherosclerosis showed an association between the -209 A/G MT2A polymorphism, CS, and zinc status. In this study, we evaluated the relationship between two MT2A polymorphisms (-209 and + 838 locus), metal status, and inflammatory/immune response in older patients with CS only (the CS1 group) or with CS and previous cerebrovascular episodes (transient ischemic attack or stroke) (the CS2 group). A total of 506 individuals (188 CS1, 100 CS2, and 218 healthy controls) were studied. Atherosclerotic patients (CS1 and CS2) showed increased levels of MT, MCP-1, and RANTES, reduced NK cell cytotoxicity, and altered trace element concentrations (zinc, copper, magnesium, iron). The +838 C/G MT2A polymorphism was differently distributed in CS1 and CS2 patients, who displayed the GG genotype (C-) with significantly higher frequency than elderly controls. C- carriers showed increased MCP-1 and decreased NK cell cytotoxicity, CD56+ cells, and intracellular zinc availability along with decreased zinc, copper, and magnesium content in erythrocytes and increased iron in plasma. C- carriers also showed a major incidence of soft carotid plaques. In conclusion, the +838 C/G MT2A polymorphism seems to influence inflammatory markers, zinc availability, NK cell cytotoxicity, and trace element status, all of which may promote CS development.  相似文献   
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