免疫印迹分析试验感染肝片吸虫和大片吸虫绵羊的IgG应答

免疫印迹(Westernblot)分析试验感染肝片吸虫和大片吸虫绵羊的抗片形吸虫分泌捧泄产物(FhESP和FgESP)IgG应答，结果表明，FhESP中分子质量在17．1～21．6ku之间的4条主要蛋白带仅被肝片吸虫感染以后(0WPI以后)的血清识别且不被对照组血清识别；FgESP中分子质量在19．0～71．1ku之间的6条主要蛋白带仅被大片吸虫感染以后(0WPI以后)的血清识别且不被对照组血清识别。     

Characterization of white wine mannoproteins

Mannoproteins, Saccharomyces cerevisiae yeast polysaccharides, play a major role in wine processing and characteristics. A systematic characterization of these polymers in terms of chemical composition and molecular structure is addressed in this study. Mannoproteins were isolated from white wine through a sequence of operations that consisted of nanofiltration for concentration of macromolecules, polysaccharide precipitation with ethanol, and affinity chromatography on concanavalin A. The whole wine mannoproteins present a very broad molecular mass distribution with several populations. Two major populations with very different compositions were separated by size exclusion chromatography. The mannoproteins with higher molecular mass are a mannose homopolymer containing 10.3% protein. The mannoproteins with lower molecular mass consisted of 87.5% of mannose and some other residues and a protein content of 2.5%. The highest molecular weight mannoprotein structure was examined by (1)H and (13)C NMR spectroscopic techniques such as 1-D TOCSY, 2-D COSY, and 2-D HMQC.     

Hybridization success of three common European cyprinid species, <Emphasis Type="Italic">Rutilus rutilus,Blicca bjoerkna</Emphasis> and <Emphasis Type="Italic">Abramis brama</Emphasis> and larval resistance to stress tests

ABSTRACT:   Hybridization success at early developmental stages and larval resistance to osmotic, thermal and fasting tests in roach Rutilus rutilus , silver bream Blicca bjoerkna , common bream Abramis brama and their F1 hybrids were investigated. Results revealed that hybrid survival rates were similar to parents. At the eyed embryo stage, however, a maternal effect was observed as a general trend during hatchling and larval stages. After these stages, hybrids displayed a higher survival rate than their parents. Under stress tests, no survival was observed after 40 min for osmotic and thermal shocks and after 24 days for the prolonged fasting test in these species and their F1 hybrids. The median survivals of hybrids were intermediate between the two parents. For total mortality, hybrids were also affected by a maternal effect but to the advantage of the hybrids.     

Ritacestus gen. n. (Cestoda: Proteocephalidea) and redescription of R. ritaii comb. n., a parasite of Rita rita (Siluriformes) in India

A new genus, Ritacestus, is proposed to accommodate Ritacestus ritaii (Verma, 1926) comb. n. (syn. Proteocephalus ritaii), a parasite of the catfish Rita rita (Hamilton) in India. The new genus, which is placed in the Gangesiinae, is characterized by (i) a small, subspherical scolex formed by four large lobes separated from one another by longitudinal grooves, with a large, widely oval to pyriform rostellum-like apical organ, larger than suckers and possessing an apical hemispherical depression; (ii) paramuscular and cortical position of some vitelline follicles (most follicles are situated medullary); (iii) ventral and dorsal bands of vitelline follicles usually uninterrupted ventral to terminal genitalia and reaching to the posterior margin of proglottides; (iv) the vagina always anterior to the cirrus-sac; (v) a large size of the body (length up to 51 cm); and (vi) development of the uterus of type 2. In its morphology, especially shape of the scolex and apical organ, and paramuscular and cortical position of some vitelline follicles, Ritacestus resembles Postgangesia Akhmerov, 1969, but differs in the presence of a genital atrium (both genital pores of Postgangesia are separate), the anterior position of the vagina (almost always posterior in the latter genus), position of vitelline follicles in cross sections (dorsal and ventral bands in Ritacestus versus only a lateral band in the latter genus), and dorsal excretory canals indistinguishable in mature and gravid proglottides of R. ritaii (well developed in Postgangesia spp.). The type and only species of the genus, R. ritaii, is redescribed on the basis of new material from the type host from the Ganges River basin in India and its neotype is designated.     

Carbonyl odorants contributing to the in-oven roast beef top note

Among the few papers related to the gas chromatography (GC)-olfactometric determination of important odorants in cooked beef aroma, only one uses roasting conditions, but none of them investigates the appealing aroma during the cooking of the piece of meat. The present paper investigates this top note as perceived from the oven, by analyzing the oven headspace using GC-"SNIF", a GC-olfactometric technique. From the different functional classes of odorants participating in overall in-oven aroma, this first paper focuses only on the role of aldehydes and ketones, as they represent the majority of aroma compounds formed during cooking. To ascertain the identification of these odorants, a microderivatization technique was used, based on (2,3,4,5,6-pentafluorophenyl)hydrazine. The resulting hydrazones exhibit very specific mass spectrometric fragments, leading to a sensitive and specific detection. A total of 23 carbonyl compounds were shown to contribute to the roast beef top note.     

Nutritional status of declining spruce (Picea abies (L.) Karst.): Effect of soil organic matter turnover rate

Foliar analysis was undertaken in two plots of Picea abies (L.) Karst., located in a watershed of Haute Ardenne, Belgium, in order to estimate the decline of the trees. Apart from a general Mg deficiency, the concentrations of the needles were in the same range as those determined in other European stands. Comparisons between healthy and declining trees within each plot revealed a general pattern of decline similar to that observed elsewhere in Western Europe. This was shown as lower Ca, Mg, Zn concentrations and water content and higher N and P concentrations of the needles collected from declining trees. It is concluded that this decline could be due to N over fertilization by the atmospheric deposition. The difference of decline between the two plots was attributed to the turnover rate of the soil organic layer which was less intensive in the most damaged plot.     

Genetic analysis of broad spectrum resistance to potyviruses using doubled haploid lines of pepper (Capsicum annuum L.)

Summary Genetic analysis of resistance to PVY in androgenetic doubled haploid lines, F1, F2 and backcross progenies of the Mexican pepper line, CM 334 (Capsicum annuum L.), was performed. Three reaction types were observed when seedlings were inoculated with several PVY strains of different pathotypes and with an American PeMV strain. Resistant genotypes never showed systemic symptoms although some individuals sporadically developed necrotic local lesions on inoculated cotyledons. Susceptible genotypes exhibited either a typical systemic mosaic or a systemic necrosis that caused the death of the inoculated seedlings. Segregation analyses indicated that resistance to pepper potyviruses in CM 334 is conferred by two genes. The first one, tentatively named Pr4, is dominant and confers the resistance to all now known pathotypes of PVY and to PeMV. The second one, tentatively named pr5, is recessive; it confers only the resistance to common strains of PVY. The systemic necrotic response is conferred by an independent dominant gene, tentatively named Pn1.     

Prediction of carbon mineralization rates from different soil physical fractions using diffuse reflectance spectroscopy

Soil carbon (C) mineralization rate is a key indicator of soil functional capacity but it is time consuming to measure using conventional laboratory incubation methods. Recent studies have demonstrated the ability of visible-near infrared spectroscopy (NIRS) for rapid non-destructive determination of soil organic carbon (SOC) and nitrogen (N) concentration. We investigated whether NIRS (350-2500 nm) can predict C mineralization rates in physically fractionated soil aggregates (bulk soil and 6 size fractions, n=108) and free organic matter (2 size fractions, n=27) in aerobically incubated samples from a clayey soil (Ferralsol) and a sandy soil (Arenosol). Incubation reference values were calibrated to first derivative reflectance spectra using partial least-squares regression. Prediction accuracy was assessed by comparing laboratory reference values with NIRS values predicted using full hold-out-one cross-validation. Cross-validated prediction for C respired (500 days) in soil aggregate fractions had an R² of 0.82 while that of C mineralized (300 days) in organic matter fractions was 0.71. Major soil aggregate fractions could be perfectly spectrally discriminated using a 50% random holdout validation sample. NIRS is a promising technique for rapid characterization of potential C mineralization in soils and aggregate fractions. Further work should test the robustness of NIRS prediction of mineralization rates of aggregate fractions across a wide range of soils and spectral mixture models for predicting mass fractions of aggregate size classes.     

Idiopathic chylothorax and lymphedema in 2 whippet littermates

Idiopathic chylothorax and limb edema was diagnosed in two 2-year-old male whippet siblings. The fact that the 2 related animals developed similar clinical signs at a young age may suggest a congenital or hereditary etiology.     

Unusual central nervous system lesions in slaughter-weight pigs with porcine circovirus type 2 systemic infection

Porcine circovirus type 2 systemic infection was diagnosed in 2 slaughter-weight pigs based on postmortem examination. The infection was associated with unusual central nervous system lesions characterized by a multifocal lymphohistiocytic to granulomatous meningoencephalomyelitis with giant cell formation. The role of these nervous system lesions in the development of the clinical signs in these pigs remains uncertain.