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Serge MORAND Frédéric BORDES Hsuan‐Wien CHEN Julien CLAUDE Jean‐François COSSON Maxime GALAN Gábor Á CZIRJÁK Alex D GREENWOOD Alice LATINNE Johan MICHAUX Alexis RIBAS 《Integrative zoology》2015,10(5):409-423
We summarize the current knowledge on parasitism‐related invasion processes of the globally invasive Rattus lineages, originating from Asia, and how these invasions have impacted the local epidemiology of rodent‐borne diseases. Parasites play an important role in the invasion processes and successes of their hosts through multiple biological mechanisms such as “parasite release,” “immunocompetence advantage,” “biotic resistance” and “novel weapon.” Parasites may also greatly increase the impact of invasions by spillover of parasites and other pathogens, introduced with invasive hosts, into new hosts, potentially leading to novel emerging diseases. Another potential impact is the ability of the invader to amplify local parasites by spillback. In both cases, local fauna and humans may be exposed to new health risks, which may decrease biodiversity and potentially cause increases in human morbidity and mortality. Here we review the current knowledge on these processes and propose some research priorities. 相似文献
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R.O. Nyankanga O.M. Olanya P.S. OjiamboH.C. Wien C.W. HoneycuttW.W. Kirk 《Crop Protection》2011,30(5):547-553
Potato tuber blight caused by Phytophthora infestans accounts for significant losses of tubers in storage. Despite research on infection and management of tuber blight, there is paucity of information on the prediction of the occurrence tuber blight or modelling of tuber infection by P. infestans under field conditions. A tuber blight prediction model was developed in New York in experiments conducted using cultivars Allegany, NY101, and Katahdin in 1998 and 1999. This model was validated using data collected from the potato cultivar Snowden in field experiments in Laingsburg, Michigan from 2000 to 2009. In both New York and Michigan experiments, disease was initiated by artificial inoculation of cultivars with a US-8 isolate of P. infestans. Mean leaf area affected ranged from 0 to 94% at New York, and 0 to 93% at Michigan. At New York and Michigan, mean tuber blight incidences ranged from 1 to 40% and 0 to 15%, respectively. In the validation of the model using data collected at Laingsburg, Michigan, the model correctly predicted tuber blight incidence in 7 out of 9 years. Comparison of observed with predicted values indicated that slopes of the regression line between observed and predicted germination and infection data were not significantly different (P > 0.3547). Correlation coefficient between observed and predicted values was high (r2 > 0.65) and the coefficient of variation of the residuals of error was about 12%. Although inoculum availability is assumed in the model, incorporation of relationships of inoculum density, propagule survival in soil, and tuber blight incidence would greatly improve the prediction of tuber blight under field conditions. 相似文献
3.
Foliar and tuber blight caused by Phytophthora infestans accounts for significant losses in potatoes in field and storage. Nevertheless, limited research has been published on the
effects of cultural practices on late blight control. Field experiments were conducted in two years on Howard gravely loam
soil in New York State to evaluate the effectiveness of mulching using oat straw and hilling in preventing tuber blight infection
for cvs Allegany and Katahdin. Potato hilling and mulching had little effect on foliar blight development. The cultivar affected
the disease development in the foliage, with cv. Allegany showing lower foliar late blight than cv. Katahdin. Tuber blight
incidence averaged 25% for cv. Allegany and 3% for cv. Katahdin in hilled plots, while in the mulched plots the incidence
of tuber blight averaged 33% for cv. Allegany and 10% for cv. Katahdin. The straw hay mulch was ineffective in tuber blight
control. Tubers set at a soil depth of more than 7 cm had lower tuber blight incidence than shallow tubers set at a depth
of less than 7 cm. In both years, hilling provided partial protection of tubers but its effectiveness was limited in the presence
of favourable conditions for late blight development. Even though large hills had proportionally a lower tuber blight incidence
than medium-sized hills, the difference between the different hill sizes was not significant. These studies suggest that the
use of cultivars with foliage resistance to late blight in combination with cultural practices may partially reduce the incidence
of tuber blight.
Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information
and does not imply recommendation for endorsement by Cornell University or the US Department of Agriculture. 相似文献
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A survey study was conducted to determine the generality of chlorinated biphenyl formation from the photolysis of chlorine-containing herbicides in aqueous solution. Seven herbicides from the phenylurea, anilide and carbamate classes were examined. In this study, the photoreaction under investigation proceeded via the coupling of two herbicide molecules to yield a chlorinated biphenyl with concomitant loss of hydrogen chloride. In preliminary studies using ultraviolet lamps, 4-chlorophenyl methylcarbamate (PPG-124) gave a chlorinated biphenyl with only one carbamate side chain, and chlorpropham gave no chlorinated biphenyl, but rather a hydroxylated biphenyl. Employing ultraviolet lamps or natural sunlight, photolyses of monuron, diuron, linuron, metobromuron and propanil produced halogenated biphenyls according to the photocoupling reaction under investigation. All yields of chlorinated biphenyls from sunlight photolysis were approximately 1% or lower. 相似文献
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Sprouts of potato tubers allowed to develop in a dark, dry environment at 60 F developed tip necrosis which was alleviated by application of calcium salts. Successive removal of sprout tips at an eye led to the formation of sprout clusters of sufficient density to cause penetration of the tuber by new sprouts arising from the cluster. The length at which the sprouts were pruned determined the density of the cluster and consequently the likelihood of internal sprouting. It is theorized that the localized calcium deficiency in severe cases could lead to the formation of similar rosettes and therefore, is implicated as a possible cause of internal sprouting. 相似文献
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Liv ?stevik Gjermund Gunnes Gustavo A de Souza Tale N Wien Randi S?rby 《Acta veterinaria Scandinavica》2014,56(1)
Localized nasal, conjunctival and corneal amyloidosis was diagnosed in a 15-year-old pony with nasal and conjunctival masses and severe dyspnoea. Multiple swellings had been evident in the nostrils for at least two years and had gradually increased in size before presentation due to dyspnoea and exercise intolerance. Surgical debulking of the masses was performed and histological examination revealed large amounts of extracellular, hyaline, eosinophilic, Congo red positive material in the lamina propria of the nasal mucosa. A tentative diagnosis of localized nasal amyloidosis was made. The treatment relieved the clinical signs, however, the nasal masses recurred and bilateral conjunctival, papillary masses developed. The horse was euthanized. Nodular nasal and papillary conjunctival masses consisting of rubbery, grey to yellow tissue were found at necropsy. At the limbus this tissue infiltrated and expanded the cornea. The masses consisted of amyloid and moderate infiltrates of T lymphocytes and B lymphocytes were present in the tissue. No predominance of either cell type was observed and no distinct neoplastic mass could be identified. Ultrastructural examination of the nasal mucosa and cornea confirmed the presence of abundant extracellular deposits of non-branching fibrils ranging from 9–11 nm in diameter consistent with amyloid. Immunohistochemistry of amyloid revealed no labelling for AA amyloid, and no peptides representing serum amyloid A (SAA) were detected by microscopic laser dissection and subsequent mass spectrometry. Peptides from immunoglobulin kappa-like light chains were detected and are suggestive of AL amyloidosis, however the results were inconclusive and a final identification of the amyloid protein could not be made.Nasal amyloidosis is a clinical entity of localized amyloid deposits in the horse. Localized amyloidosis involving the conjunctiva of the horse is previously described in only seven cases and the present case is the first case of combined, localized nasal and corneal amyloidosis in the horse. In several reported cases surgical excision has provided clinical improvement and return to normal levels of exercise, while medical treatment has had no effect. The present case however, shows that rapid recurrence and progression of nasal amyloidosis to involve ocular tissues can occur and lead to recurrent respiratory obstruction.
Electronic supplementary material
The online version of this article (doi:10.1186/s13028-014-0050-6) contains supplementary material, which is available to authorized users. 相似文献7.
Ira Handayani Hamada Saad Shanti Ratnakomala Puspita Lisdiyanti Wien Kusharyoto Janina Krause Andreas Kulik Wolfgang Wohlleben Saefuddin Aziz Harald Gross Athina Gavriilidou Nadine Ziemert Yvonne Mast 《Marine drugs》2021,19(6)
Indonesia is one of the most biodiverse countries in the world and a promising resource for novel natural compound producers. Actinomycetes produce about two thirds of all clinically used antibiotics. Thus, exploiting Indonesia’s microbial diversity for actinomycetes may lead to the discovery of novel antibiotics. A total of 422 actinomycete strains were isolated from three different unique areas in Indonesia and tested for their antimicrobial activity. Nine potent bioactive strains were prioritized for further drug screening approaches. The nine strains were cultivated in different solid and liquid media, and a combination of genome mining analysis and mass spectrometry (MS)-based molecular networking was employed to identify potential novel compounds. By correlating secondary metabolite gene cluster data with MS-based molecular networking results, we identified several gene cluster-encoded biosynthetic products from the nine strains, including naphthyridinomycin, amicetin, echinomycin, tirandamycin, antimycin, and desferrioxamine B. Moreover, 16 putative ion clusters and numerous gene clusters were detected that could not be associated with any known compound, indicating that the strains can produce novel secondary metabolites. Our results demonstrate that sampling of actinomycetes from unique and biodiversity-rich habitats, such as Indonesia, along with a combination of gene cluster networking and molecular networking approaches, accelerates natural product identification. 相似文献
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Photochemical demethylation of monuron [3-(4-chlorophenyl)-1, 1-dimethylurea] and of demethylmonuron [ 1-(4-chlorophenyl)-3-methylurea] in aqueous solution was investigated. The photoproducts identified in this study were formaldehyde, formic acid and carbon dioxide. These products indicate that demethylation occurs either by oxidation of a methyl group to hydroxymethyl which is readily cleaved to yield formaldehyde, or by further oxidation to an N-formyl group, which is slowly hydrolysed under weakly acidic conditions to yield formic acid. Samples equilibrated either with air or oxygen (> 99 % purity) gave essentially the same yield of oxidation products. Experimental evidence indicated that extensive photodegradation of formaldehyde was occurring during photolysis, causing low recoveries of formaldehyde. Consequently, with [2H3-methyl]demethylmonuron and deuterated water, only steady state concentrations of formaldehyde could be measured in an isotopic study. 相似文献
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An 8-wk growth trial was conducted to assess the effects of continuous infusion of thyrotropin-releasing hormone (TRH) and an active TRH analog less than Aad-His-Pro-NH2 (the less than Aad is L-pyro-alpha-aminoadipic acid) on growth trial performance, carcass composition and hormone profiles of growing lambs. Both drugs were infused at 600 micrograms X lamb -1 X d -1 with 16 lambs/treatment. Both TRH and less than Aad-His-Pro-NH2 decreased average daily gain (ADG; P less than .01) and increased feed conversion (FC; P less than .01) compared with saline infused controls. Average daily feed intake was not altered. Carcasses of lambs given TRH or less than Aad-His-Pro-NH2 contained fewer kilograms of moisture (P less than .05) and appeared to contain fewer kilograms of protein. Thyrotropin-releasing hormone and less than Aad-His-Pro-NH2 increased thyroid gland weights (P less than .05), but pituitary gland weights were not different. Plasma thyrotropin (TSH) concentrations were increased by both drugs compared with control lambs, peaking at 4 to 7 d after initiating infusion. However, by 14 d, TSH concentrations returned to control levels. Triiodothyronine (T3) and thyroxine (T4) were elevated by both drugs over the entire 8-wk trial, with peak levels reached at 10 d and maintained for the duration of the study. Both TRH and less than Aad-His-Pro-NH2 increased prolactin over the entire period. Growth hormone levels were not altered by either drug. The effects of less than Aad-His-Pro-NH2 infusion on growth trial performance, carcass composition and hormone profiles of growing lambs were very similar to TRH. The negative effects of TRH and less than Aad-His-Pro-NH2 infusion on ADG, FC and carcass protein appear to be the result of elevated T3 and T4 levels. 相似文献
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