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1.
Surveillance of hepatitis E virus (HEV) in risk groups is an important strategy to monitor its circulation pattern and to timely detect changes thereof. The aims of this cross-sectional study were to estimate the prevalence of HEV infections in pigs and humans from different regions of the country, to identify risk factors for increasing anti-HEV IgG prevalence and to characterize HEV strains. The presence of anti-HEV antibodies was assessed by commercial ELISA in serum samples from the general population, farm and slaughterhouse employees, as well as pigs sampled in the three regions of Cuba from February to September 2016. Overall, individuals with occupational exposure to swine or swine products (70/248, 28.2%) were 4 times more likely to be seropositive compared to the general population (25/285, 8.7%; OR: 4.18; p < .001). Within the risk group, risk factors included age, number of years working in a professional activity with direct exposure to swine, geographic region and distance between residence and closest professional swine setting, while wearing gloves had a protective effect. Prevalence of total anti-HEV antibodies in swine was 88.2% (165/187) and HEV RNA was detected by real-time RT-PCR in 9.2% (16/173) swine stools. All HEV strains sequenced clustered within genotype 3. Some strains clearly belonged to subtype 3a, while another group of strains was related with subtypes 3b and 3 k but partial HEV sequences did not allow unequivocal subtype assignment. These findings suggest that the high HEV exposure in Cuban individuals with swine-related occupations could be due to enzootic HEV in certain regions, direct contact with infectious animals or their products as well as environmental contamination.  相似文献   
2.
The marine environment is a rich source of biologically active molecules for the treatment of human diseases, especially cancer. The adaptation to unique environmental conditions led marine organisms to evolve different pathways than their terrestrial counterparts, thus producing unique chemicals with a broad diversity and complexity. So far, more than 36,000 compounds have been isolated from marine micro- and macro-organisms including but not limited to fungi, bacteria, microalgae, macroalgae, sponges, corals, mollusks and tunicates, with hundreds of new marine natural products (MNPs) being discovered every year. Marine-based pharmaceuticals have started to impact modern pharmacology and different anti-cancer drugs derived from marine compounds have been approved for clinical use, such as: cytarabine, vidarabine, nelarabine (prodrug of ara-G), fludarabine phosphate (pro-drug of ara-A), trabectedin, eribulin mesylate, brentuximab vedotin, polatuzumab vedotin, enfortumab vedotin, belantamab mafodotin, plitidepsin, and lurbinectedin. This review focuses on the bioactive molecules derived from the marine environment with anticancer activity, discussing their families, origin, structural features and therapeutic use.  相似文献   
3.
The objective of this work was to evaluate the association between morphometric variables and carcass characteristics in Pirapitinga. We used a thousand specimens of Pirapitinga with an average weight of 1,200 g, which were stunned, slaughtered, weighed, measured, and processed for morphometric and processing yield analysis, to obtain weights, carcass and fillet yields. Initially, the linearity of the variables was verified. Pearson's simple and partial correlation tests were performed between all metrics. Track analysis was performed considering the weights and yields of carcass and filet as dependent variables and the others as independent variables. Ridge regression models were used to eliminate the effects of multicollinearity among the independent variables. Observations showed that the simple correlations between body weights and yields were superior to the partial ones in terms of magnitude. The length and circumference of the specimens were the measures most linearly associated with weight, carcass weight and fillet with rib weight. As for carcass yield and fillet yield, linear correlation coefficients were low and not significant when associated with body weights. With the path analysis, we could observe significant positive correlations between the morphometric measurements for weight, carcass weight and fillet with rib weight. The standard length, body circumference and body circumference/body height ratio are the most correlated. The latter are the most important variables in the evaluation of body weights in Pirapitinga fish. They can serve as criteria for indirect selection in searching for fish with better carcass characteristics. As for fillet and carcass yields, the morphometric variables have not shown to be efficient for indirect selection.  相似文献   
4.
Robenidine as an anticoccidial agent alone (in doses of 50 and 100 mg/kg) or in association with two other antiprotozoal compounds--pyrimethamine and sulfadoxine (in doses of 2.5 and 250 mg/kg, respectively) were tested in the treatment of chronically infected mice with an avirulent cyst-forming HF strain of Toxoplasma gondii. The efficacy of the used drugs was evaluated by the cysts number in the brains of treated mice versus control group, antibody level and viability of survived cysts by the consecutive infection of mice. According to these criteria none of the tested drugs alone or combined exhibited to be able to produce an effective cure of cyst-stage of toxoplasmosis in experimental mice.  相似文献   
5.
6.
Antibacterial activity of seed proteins of Robinia pseudoacacia   总被引:1,自引:0,他引:1  
A low molecular weight cationic peptide was isolated from Robinia pseudoacacia seed and tested in vitro against seven bacteria (Corynebacterium michiganense, Staphylococcus aureus, Bacillus subtilis, Erwinia carotovora subsp. carotovora, Pseudomonas syringae pv syringae, Xanthomonas campestris pv campestris, and Escherichia coli). The peptide inhibited the growth of the tested strains. The effective concentrations required for 50% inhibition of bacterial growth ranged between 20 and 120 microg ml(-1) protein. S. aureus was found to be the most sensitive strain, however, E. coli was not affected much when compared with others. Reduction of antibacterial activity of the peptide with CaCl2 addition into the growth medium was also observed.  相似文献   
7.
This work introduces the development and application of a multi-goal evaluation procedure for assessing sets of remedial options that have previously been found technically suitable for managing a certain contaminated site. The construction of this decision support tool, in the form of a balanced scorecard, has followed a multi-attribute conception of the contaminated sites problem, identifying the most critical aspects considered by all stakeholders involved in contaminated sites management decisions. The developed tool has been checked in its formulation and application against an export benchmark of an Austrian remediation project. The performed evaluation allowed to identify and suggest a remedial option that best fitted the expectations of all stakeholders involved in the project. Furthermore, through the accomplishment of a sensitivity analysis it has been demonstrated that the system is stable and robust in terms of the chosen elicitation schemes, and that the preferences of the different stakeholders are influencing factors on the final result. The results and conclusions of this work present the benefits of implementing the developed balanced scorecard as a tool for supporting decision making in contaminated sites remediation projects.  相似文献   
8.
Zearalenone is a mycotoxin widely occurring in cereals and animal feed, and it is associated with hyperestrogenism and other reprodutive disorders in animals. A new method of detoxication of feedstuffs involves alkaline hydrolysis of toxic macrolactone (1) (as well as model compounds (2a, 2b)). The method caused modification of zearalenone structure under mild conditions and the toxin underwent irreversible hydrolysis with high efficiency.  相似文献   
9.
During the last ten years, numerous species have been treated with deslorelin implants to induce contraception. The aims of the study were 1) to assess contraceptive efficacy of 4.7 mg subcutaneous deslorelin implants in rats, 2) to determine the latency of contraceptive effect, and 3) to determine potential side effects. Three experimental females were implanted and their estrous cycle was studied by vaginal smear. Two weeks after implantation, a male whose fertility was previously assessed with a control female, was introduced into their cage. No female conceived during the 4 mo following implantation. Additionally, 38 pet rats were recruited from clients in practice to test for potential side effects, including 6 males and 32 females with a mean age of 14 mo. Local reaction and transient weight gain during the first 2 wk, as well as behavioral changes were recorded. According to this pilot study, deslorelin implant could be used as a contraceptive method in female rats. The latency period is about 2 wk. Nevertheless, it might be possible to refine the treatment further using hormonal measurements. The duration of contraceptive effect is to be determined in an upcoming study.  相似文献   
10.
Steeping in dilute alkaline (0.2% NaOH) followed by resteeping in biocontrol (starters of Bacillus subtilis S499) has been used during red sorghum malting. The effect of steeping and germination conditions has been described using 2 functions: a Weibull 4-parameter model combined with a General Linear Model with Logarithm Link with significant goodness. Steeping conditions (combined use of NaOH and B. subtilis S499) affects the synthesis capacity of grain: when B. subtilis culture used in the steeping step is diluted, ln α increases, suggesting a loss of treatment efficacy. The germination temperature affects the β-amylase synthesis rate during the induction phase: the germination temperature increase is accompanied by a decrease of the β-amylase synthesis rate. During the repression phase of β-amylase synthesis, the effect of malting conditions was found to taper.  相似文献   
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