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11.
Are rhododendron hybrids distinguishable on the basis of morphology and microsatellite polymorphism?
Sequence Tagged Microsatellite Sites (STMSs) and morphological trait markers were used to evaluate 33 rhododendron germplasm for genetic diversity assessment and discrimination power. The average genetic diversity estimates were 0.724 (morphological traits) and 0.174 (STMSs) marker datasets. The Shannon index was higher for morphological traits (1.797) than STMS (0.302). The correlation coefficients obtained by the Mantel matrix correspondence test, which was used to compare the cophenetic matrices for the two markers, showed that estimated values of relationships given for morphological and STMS were not significantly related (p > 0.05). The dataset from STMS, supported by the total probability of identity (1.13 × 10−9) and total paternity exclusion probability (0.9999), allowed all accessions to be uniquely identified. In summary, STMS marker proved to be an efficient tool in assessing the genetic variability among old broad leaf rhododendron genotypes. The pattern of variation appeared to be consistent, and it can be used for germplasm conservation and management for restoration of historical genetic resources. 相似文献
12.
Angioni A Barra A Russo MT Coroneo V Dessi S Cabras P 《Journal of agricultural and food chemistry》2003,51(10):3073-3078
The composition of the essential oil from ripe and unripe berries and leaves of Juniperus oxycedrus L. ssp. oxycedrus, Juniperus phoenicea ssp. turbinata and Juniperus communis ssp. communis was analyzed by GC-MS, and microbiological assays were carried out. Samples were collected in different localities (Sardinia, Italy) and hydro distilled. The yields ranged between 2.54% +/- 0.21 (v\w dried weight) and 0.04% +/- 0.00. A total of 36 components were identified. The major compounds in the essential oils were alpha-pinene, beta-pinene, delta-3-carene, sabinene, myrcene, beta-phellandrene, limonene, and D-germacrene. Both qualitative and quantitative differences between species and between different parts of the plant were observed. The essential oils and their major compounds were tested against Candida albicans, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, and the minimum inhibitory concentration and minimum bactericidal concentration were determined. The results obtained led to a nonsignificant inhibitory effect, although all the essential oils from Juniperus phoenicea ssp. turbinata and the essential oil from leaves of Juniperus oxycedrus ssp. oxycedrus exhibited rather good or weak activity against Candida albicans and Staphylococcus aureus. 相似文献
13.
A new test method for the evaluation of total antioxidant activity of herbal products 总被引:2,自引:0,他引:2
Zaporozhets OA Krushynska OA Lipkovska NA Barvinchenko VN 《Journal of agricultural and food chemistry》2004,52(1):21-25
A new test method for measuring the antioxidant power of herbal products, based on solid-phase spectrophotometry using tetrabenzo-[b,f,j,n][1,5,9,13]-tetraazacyclohexadecine-Cu(II) complex immobilized on silica gel, is proposed. The absorbance of the modified sorbent (lambda(max) = 712 nm) increases proportionally to the total antioxidant activity of the sample solution. The method represents an attractive alternative to the mostly used radical scavenging capacity assays, because they generally require complex long-lasting stages to be carried out. The proposed test method is simple ("drop and measure" procedure is applied), rapid (10 min/sample), requires only the monitoring of time and absorbance, and provides good statistical parameters (s(r)相似文献
14.
Steven J. Kennelly Valentina Melli Matt K. Broadhurst 《Fisheries Management and Ecology》2019,26(6):630-637
Penaeid trawling is among the world's least selective fishing methods; a characteristic that has evoked spatial closures being implemented in some fisheries if certain bycatch limits are exceeded. For decades, considerable work has been done to develop modifications to penaeid trawls that reduce unwanted bycatches, with most focussed at the posterior section (i.e. codend). More recently, efforts have examined ways to prevent bycatch entry into trawls entirely—via modifications to anterior components. This study assessed the utility of proactively lowering the headlines of Australian penaeid trawls, using clips at the otter boards, to 68% and 54% of their conventional height, and demonstrated mean total bycatch reductions (by weight) of 69% and 79%, respectively, with no effects on the targeted Metapenaeus macleayi (Haswell). The results provide insights into the location and behaviour of various species in the water column preceding capture, and support a simple and easy method for regional fishers to use in situ to avoid excessive bycatch and associated fishing closures. More broadly, the data support ongoing efforts in other penaeid‐trawl fisheries to reduce bycatches via similar, rapid adjustments to anterior components, depending on species‐specific behaviours during capture. 相似文献
15.
Rodriguez-Rodriguez R Perona JS Herrera MD Ruiz-Gutierrez V 《Journal of agricultural and food chemistry》2006,54(6):2096-2102
There is currently a considerable amount of interest in the benefits of certain dietary elements, and in particular of olive oil, in endothelial function and thus in hypertension. "Orujo" or pomace olive oil is obtained from the residues of the olive by a novel centrifugation process, and it is a good dietary source of triterpenic compounds such as oleanolic and maslinic acid, erythrodiol, and uvaol. Until now, there was no information available regarding the properties of these triterpenoids on the vasculature of hypertensive animals. However, in this in vitro study, we have analyzed the vasorelaxation induced by these triterpenoids in isolated aorta from spontaneously hypertensive rats (SHR). The triterpenoids tested induced concentration-dependent vasorelaxation, mostly involving nitric oxide (NO). Indeed, the responses were attenuated by removal of the endothelium or following pretreatment with the NO synthase inhibitor L-NAME. Furthermore, the differences that were observed in the potency of relaxation, the selectivity, and the dependence on the endothelium were attributed to structural features of the triterpenoids. In conclusion, triterpenic components in pomace olive oil induce vasorelaxation of the aorta from SHR, and this effect generally involves endothelial NO. 相似文献
16.
Valentina Vitale Rita Balocchi Maurizio Varanini Micaela Sgorbini Alberto Macerata Claudio Sighieri Paolo Baragli 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(5):400-403
Analysis of heart rate variability (HRV) is a noninvasive approach for investigating the sympathovagal balance of the autonomic nervous system. In recent years, HRV has been increasingly evaluated in animal research. In horses, it has been suggested that basal resting conditions can be achieved by restraining them. The aim of this study was to verify how restriction of movement influences HRV i2n horses. Ten healthy standardbred mares were used to measure the electrocardiographic signal under 2 conditions: free to move in the stall and restrained in the stock. Results indicate that the restriction of movement is associated with increased nervous system sympathetic activity not consistent with resting conditions. 相似文献
17.
Spagnolo V Crippa V Marzia A Alberti I Sartorelli P 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(2):225-228
BACKGROUND: The tawny owl (Strix aluco) is a protected species in Italy. Orphaned, injured, and ill owls often are sheltered and treated in rehabilitation centers, where hematologic and biochemical analyses would be helpful to evaluate and monitor the status of their health. OBJECTIVES: The major aim of this work was to assess hematologic and biochemical constituents together with protein electrophoretic fractions in healthy tawny owls. In addition, we compared laboratory methods for determining hemoglobin (Hgb), total protein, and albumin concentrations. METHODS: Heparinized blood samples were collected from 10 clinically healthy adult captive tawny owls between March 2001 and November 2003 for CBC, routine biochemical analysis, and protein electrophoresis. Alternate methods for Hgb (estimation as HCT/3 vs spectrophotometry), total protein (biuret vs refractometry), and albumin (bromcresol green vs electrophoresis) concentrations were compared in 34 samples from 16 unhealthy adult owls and 8 nestlings. RESULTS: Results were reported as mean, median, and range (minimum-maximum). Significant differences and poor concordance were observed between methods for Hgb, total protein, and albumin. CONCLUSIONS: Hematologic and plasma biochemical values in captive tawny owls may be useful in evaluating and monitoring the health of this species in captivity. 相似文献
18.
Patrizia CASAGRANDE PROIETTI Valentina STEFANETTI Doreene Rose HYATT Maria Luisa MARENZONI Stefano CAPOMACCIO Mauro COLETTI Annalisa BIETTA Maria Pia FRANCIOSINI Fabrizio PASSAMONTI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(8):945-951
Biofilm-forming ability is increasingly being recognized as an important virulence factor in several Staphylococcus species. This study evaluated the biofilm-forming ability of sixty canine derived clinical isolates of S. pseudintermedius, using three phenotypic methods, microtiter plate test (MtP), Congo red agar method (CRA) and tube adherence test, and the presence and impact of biofilm-associated genes (icaA and icaD). The results showed that icaA and icaD genes were detected concomitantly in 55 (91.7%) of 60 isolates. A majority (88.3%) of the strains screened had matching results by the tube adherence test, MtP and PCR analysis. Better agreement (95%) was found between the PCR-based analysis and the CRA. Results of the icaA and icaD gene PCRs showed good agreement with CRA results, with a kappa of 0.7. Comparing the phenotypic methods,
the statistical analysis showed that the agreement among the phenotypical tests using categorical data was generally good. Considering two classes (biofilm producer and biofilm non-producer), the percentage of matching results between the CRA method and the tube adherence test and between the CRA method and the MtP was 93.3%. A concordance of 100% was revealed between the MtP and the tube adherence test. The results indicate a high prevalence of the ica genes within S. pseudintermedius isolates, and their presence is associated with in vitro formation of a biofilm. A combination of phenotypic and genotypic tests is recommended for investigating biofilm formation in S. pseudintermedius. 相似文献
19.
Francesco Faggioli Graziella Pasquini Valentina Lumia Gaetano Campobasso Timothy L. Widmer Paul C. Quimby Jr 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(4):353-360
In the United States, yellow starthistle (Centaurea solstitialis) is an annual invasive weed with Mediterranean origins. Malformed plants displaying witches' broom, fasciations, abortion of buds and flower virescence symptoms were observed in central Italy. Attempts to transmit the causal agent from the natural yellow starthistle host to periwinkle by grafting, resulted in typical symptoms of a phytoplasma, i.e. yellowing and shortening of internodes. The detection of phytoplasmas was obtained from both symptomatic yellow starthistle and periwinkle by the specific amplification of their 16S-23S rRNA genes. PCR amplification of extracted DNA from symptomatic plant samples gave a product of expected size. Asymptomatic plants did not give positive results. An amplicon obtained by direct PCR with universal primers P1/P7 was cloned and sequenced. The homology search using CLUSTALW program showed more than 99% similarity with Illinois elm yellows (ILEY) phytoplasma from Illinois (United States) and 97% with Brinjal little leaf (BLL) phytoplasma from India. Digestion of the nested-PCR products with restriction enzymes led to restriction fragment length polymorphism patterns referable to those described for phytoplasmas belonging to the clover proliferation (16S-VI) group. Since this is a previously undescribed disease, the name Centaurea solstitialis virescence has been tentatively assigned to it. This is a new phytoplasma with closest relationships to ILEY and BLL, but distinguishable from them on the basis of 16S rDNA homology, the different associated plant hosts and their geographical origin. 相似文献
20.
Paolo Borghetti Roberta SaleriLuca Ferrari Marina MorgantiElena De Angelis Valentina FranceschiEzio Bottarelli Paolo Martelli 《Comparative immunology, microbiology and infectious diseases》2011,34(2):143-155
The objective of this paper was to study the changes of some cytokines and neuroendocrine hormones in vaccinated and unvaccinated pigs that were naturally infected by a PRRSV-1 (porcine reproductive and respiratory syndrome virus) heterologous field strain. We analyzed gene expression of pro-inflammatory (TNF-α, IL-1β, MCP-1, IL-6), pro-immune (IFN-γ) and anti-inflammatory cytokines (IL-10) in PBMC, as well as hormonal (GH and cortisol) levels in blood samples of pigs obtained in a field trial previously reported [Martelli P, Gozio S, Ferrari L, Rosina S, De Angelis E, Quintavalla C, et al. Efficacy of a modified-live porcine reproductive and respiratory syndrome virus (PRRSV) vaccine in pigs naturally exposed to a heterologous European (Italian cluster) field strain: clinical protection and cell-mediated immunity. Vaccine 2009;27:3788-99]. All vaccinated pigs showed an increase in pro-inflammatory and pro-immune cytokine gene expression with respect to controls and a prompt increase in GH that could be consistently associated with pro-inflammatory cytokines in sustaining innate immunity; moreover, the higher levels of cortisol indicates the activation of the hypothalamus-pituitary-adrenal (HPA) axis response. In contrast, unvaccinated pigs showed down-regulation of the cortisol and GH responses, and the pro-inflammatory and pro-immune cytokines remained at a basal or low level, with an increase of TNF-α and IL-6 in association with a higher level of IL-10 in the late phase of natural infection. The associated trends of pro-inflammatory and anti-inflammatory cytokines together with the cortisol level demonstrate that a previous vaccination promotes an early immune responsiveness in pigs and a more efficient control of inflammation in the late phase of infection with a heterologous PRRSV isolate; both events could sustain clinical protection. 相似文献