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31.
Basal hexapodan orders (Apterygota) are traditionally divided in two well defined taxonomic groups, Entognatha and Ectognatha. Entognathy (the enclosed mouthparts condition) is considered the most distinctive character joining the Ellipura (Protura+ Collembola) with the order Diplura, whereas the presence of exposed mouthparts (ectognathy) is the feature shared by Microcoryphia and Zygentoma with the pterygote insects. In spite of the growing interest for the evolutionary history of the Apterygota, there is no complete agreement among the general phylogenetic hypotheses based on the study of morphological characters. In this study we analyzed the DNA sequence of segments of the nuclear Elongation Factor-1α(EF-1α) and of the mitochondrial 12S rRNA genes, and used different methods of phylogenetic reconstruction. The 12S gene seems to be more suited than the EF-1α to resolve some of the most outstanding systematic disputes, whereas the lack of resolution at the deeper nodes does not allow to assess the phylogenetic relationships within Microcoryphia and between ectognathan orders. We have obtained a fairly high support for the monophyly of the orders Diplura and Zygentoma. In the 12S analysis, the Ellipura and the Entognatha form monophyletic assemblages. In addition, the study of the distribution of introns in the EF-1α suggests a relationship between Collembola and Diplura.  相似文献   
32.
Purpose

The effects of long-standing industrialization processes and poor environmental management practices have often left a harmful legacy for marine-coastal sites worldwide, causing a wide range of unforeseen impacts on the ecosystem and on human health. A critical revision of available data from three highly contaminated Italian sites (Augusta Bay, Sicily; Cagliari Gulf, Sardinia; Pozzuoli Bay, Campania) revealed the crucial role of biogeochemical/physical dynamics and potential widespread delivery of contaminants as key components for a wider comprehensive sediment management.

Materials and methods

Datasets of organic pollutants (ΣPAHs, ΣPCBs), heavy metals (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, V, and Zn), radionuclides, and grain size composition of marine sediments of all three sites were critically reviewed and seafloor bathymetric data were analyzed.

Results and discussion

A critical review of available physical and chemical information of sediments collected from the three marine sites provides a better understanding of the physical and biogeochemical dynamics of large-scale dispersion of contaminants in those areas, as well as new insights in terms of improved sediments management policies with actions of larger scale monitoring of the “buffer zone confining with the national relevance and highly contaminated site to trace inputs and accumulation effects of pollutants deriving from the point-source.

Conclusions

This study demonstrates how the presence of polluted sediments on the coastal areas can have, also after the closure of anthropogenic activities, a potential impact at a large scale. Then to better evaluate the effective impact, we suggest the adoption of a buffer zone contiguous to the national relevance sites (SIN) area. While SINs are optimized to define the state of the art of the near-source pollution, buffer zones may help to outline the rate of delivery of pollutants to the deep sea. Buffer zones must be designed by taking into account the local hydrodynamics, sedimentology, and geomorphology, and should be monitored, even if at a lower resolution, like SINs.

  相似文献   
33.
The yellow clam Mesodesma mactroides (Mesodesmatidae) is a sandy beach bivalve that is distributed from Rio de Janeiro, Brazil, to the south of Buenos Aires province, Argentina. The yellow clam population has been declining in recent decades. To increase our understanding of this species, we evaluated the immunological status of yellow clams collected during different seasons from various areas in the state of Rio Grande do Sul, Brazil. We characterized the hemocytes, determined the differential hemocyte counts (DHCs), calculated the apoptotic index, and evaluated the incidence of parasites in yellow clams through histological analysis. We identified two types of hemocyte (hyaline and granular) that showed significant variation in DHCs among sampling areas during the summer and winter. The apoptotic index only exhibited significant variation during the summer. Histopathological analysis results did not significantly differ among sampling areas. This work demonstrated that environmental variation (e.g., temperature and salinity) associated with anthropogenic actions may be affecting the immune system of yellow clams. However, more studies are needed to determine the full influence of these factors on the yellow clam’s immune system and thus contribute to future management and aquaculture of the species.

Received May 10, 2015; accepted October 28, 2015.  相似文献   

34.
35.
Although the culture of Mycobacterium avium subsp. paratuberculosisis is the gold standard for the diagnosis of paratuberculosis, this bacterium is difficult to grow. In contrast, serological tests like ELISAs are inexpensive, rapid, and easy to perform. The aims of this study were to evaluate the accuracy of three different ELISAs: one with the commercial antigen PPA-3, another one with L5P (a recently described lipopentapeptide), and a third one with an in-house antigen whole cell lysates (WCL) of M. avium (MAA) strain D4ER (Study 1), and to compare them with other tests for paratuberculosis (PTB) diagnosis (Study 2). In Study 1, the sensitivities of the three ELISAs tested were 74.1%, 37% and 74.1%, respectively, whereas their specificities were 98.9%, 100% and 100%, respectively. In Study 2, we compared the three above-mentioned ELISAs with the intradermal reaction test using Avian PPD (PPDa) and fecal culture associated with Ziehl-Neelsen stain and PCR tests, in a dairy herd with 4.6% of cows with clinical signs of PTB. The results showed that fecal samples from 14 cows (16%) were culture-positive and that fecal samples from nine cows (10%) were PPDa-positive. Most of these animals (culture-positive and PPDa-positive) were detected as positive with any of the three ELISAs tested. Serological results showed that 31% of the animals were positive to ELISA-PPA-3, 17% to ELISA-L5P and 42.5% to ELISA-WCL. The combination of these three ELISAs identified 50.6% of the animals as positive in the infected herd. In particular, the results show that the locally developed ELISA seems to be useful for identifying many infected animals in a herd.  相似文献   
36.
Paratuberculosis or Johne's disease is a chronic infectious disorder caused by Mycobacterium avium subsp. paratuberculosis (Map). The disease produces diarrhea and weight loss in cattle and other animal species, and it is characterized by granulomatous enteritis and lymphadenitis. Histopathology and in situ techniques can be used as a diagnostic test, but the performance of these methods was not previously compared. The aim of this paper was to evaluate the ability of immunohistochemistry and in situ hybridization to detect Map in formalin-fixed tissue samples from infected cattle. Samples (ileum or ileocecal lymph node) from four animals that had positive Map culturing, lesions and detectable acid fast bacilli, as well as from two control animals, were tested by immunohistochemistry and in situ hybridization. Immunostaining and positive hybridization were observed in areas with lesions from infected animal samples, inside the cytoplasm of macrophages, epithelioid and giant cells. Immunostaining was intense in three samples and weak in one, while hybridization was weak in all cases. In situ hybridization was positive in negative areas of tissues analyzed by immunohistochemistry, which could be related to spheroplast detection as it was previously described for this method. Control samples resulted negative by these two methods. Both techniques were able to detect Map in formalin fixed and paraffin embedded tissues, however immunohistochemistry produced higher intensity staining and was easier to perform. Therefore, we believe that immunohistochemistry and in situ hybridization to be useful for the post-mortem diagnosis and research of Paratuberculosis.  相似文献   
37.
A 7-y-old, intact male Alaskan Malamute was presented with a 3-mo history of stertor and epistaxis. Computed tomography of the skull revealed generalized loss of gas throughout both nasal passages with replacement by a soft tissue mass that traversed the cribriform plate. Histopathology revealed neoplastic neuroblast cells arranged in anastomosing cords, as well as separately located aggregates of ganglion cells. Both neoplastic cell populations demonstrated immunoreactivity to MAP-2, TuJ-1, and synaptophysin. Neuroblastic cells additionally exhibited punctate immunoreactivity to MCK and CK8/18. We document here both the positive neural immunohistochemical markers for this neoplasm, as well as propose possible histomorphologic variants.  相似文献   
38.
Due to its remarkable sediment pollution caused by past industrial activities, the Mediterranean coastal area facing the town of Cogoleto (near Genoa) has been declared of “national interest”. Seven sediment cores were analysed to provide information on history and trend of heavy metal inputs, with a particular focus on Cr. Grain-size compositions and 210Pb chronologies account for a strong influence of terrigenous inputs near the coast and the mouth of the Lerone Creek (draining the industrial settlement), with sand contents and accumulation rates varying from 40.3% and 0.7 cm year?1 near shore to 2.5% and 0.1 cm year?1 offshore. Heavy metal concentrations are high, notably Cr and Ni, and to a lesser extent, Ag, Hg, Pb, Cu and Zn. Cr, that shows past values up to 3,642 µg g?1, presents only minor recent decreases. In the area, it has both natural and anthropogenic sources and their relative contributions were distinguished on the basis of Cr/Ni ratios. These are 1–1.5 in soils and rocks of the Lerone Creek catchment area but reach very high values (up to 10) in marine sediments due to the anthropogenic contribution. The anthropogenic influence is higher near the creek mouth, gradually decreases offshore and is negligible at the most distal site (ca. 2.9 km from the coast).  相似文献   
39.
SUMMARY: Selection indices were developed for combining marker information and animal model PTA for offspring, grandoffspring, and great-grandoffspring of sires. The sires had marker-QTL linkages identified in granddaughter designs (GDD). Effects of size and s. e. of marker effects and of weight given to own and progeny records in PTA on gain in accuracy of selection due to a marker were quantified. Gains were negligible for high weight or large s. e., even if the marker effect was substantial. Gains were compared among offspring (O), grandoffspring (GO), and great-grandoffspring (GGO), when the marker effect in the sire was the only marker information. Gains decreased strongly for GO and were smallest for GGO. Assuming that progeny test (PT) daughters of some sons of the sire were also marker genotyped, the selection index was mo dified to incorporate this marker information on sons in addition to that on the sire from the GDD for selection of GO. For the current size of the PT, gain from including marker data on PT daughters was negligible, requiring 200 to 1000 PT daughters. Polymorphism Information Content (PIC) was computed as the fraction of O, GO, and GGO with marker allelic inheritance traceable to the sire. PIC in GO exceeded .8 and approached PIC in O only if a marker had at least 10 alleles at equal frequencies. ZUSAMMENFASSUNG: Verwendung von genetischen Markern bei Enkelin-Selektionspl?nen Selektionsindices wurden hergeleitet, um Information von Markergenorten zu kombinieren mit Tiermodell-Zuchtwerten für Nachkommen der ersten, zweiten und dritten Generation von Vatertieren. Die Vatertiere hatten Marker-QTL Kopplungsbeziehungen, die in "granddaughter designs (GDD)" nachgewiesen worden waren. Die Einflüsse von Gr??e und Standardfehlern der Markereffekte und der Gewichtung von Eigen- und Nachkommenleistungen im Tiermodell-Zuchtwert auf die Verbesserung der Selektionsgenauigkeit durch die Markerinformation wurden ermittelt. Verbesserungen waren gering für hohe Gewichtung oder gro?e Standardfehler. Verbesserungen wurden verglichen für Nachkommen der ersten, zweiten und dritten Generation, wenn die Markerinformation nur aus dem GDD stammte. Verbesserungen waren stark reduziert bzw. sehr gering für Nachkommen der zweiten bzw. dritten Generation. Der Selektionsindex wurde modifiziert, um begrenzte Markerinformation von T?chtern aus der Nachkommenprüfung von S?hnen eines Vatertieres miteinzubeziehen. Diese Information war nur hilfreich, wenn mindestens 200 bis 1000 T?chter getestet waren. Der Polymorphismus-Informationsgehalt (PIC) wurde berechnet als der Anteil von Nachkommen der ersten, zweiten und dritten Generation, für den die Vererbung eines Markeralleles zum Vatertier zurückverfolgt werden konnte. Zumindest 10 Allele mit gleichen Frequenzen waren notwendig, um ein PIC von .8 und ein PIC in Nachkommen der zweiten Generation von ?hnlich hohen Wert wie für Nachkommen der ersten Generation zu erhalten.  相似文献   
40.
OBJECTIVE: To compare efficacy and safety of paste formulations of firocoxib and phenylbutazone in horses with naturally occurring osteoarthritis. DESIGN: Randomized controlled clinical trial. ANIMALS: 253 client-owned horses with naturally occurring osteoarthritis. PROCEDURES: Horses were treated with firocoxib (0.1 mg/kg [0.045 mg/lb], PO, q 24 h) or phenylbutazone (4.4 mg/kg [2 mg/lb], PO, q 24 h) for 14 days. Physical examinations and lameness evaluations were performed prior to treatment and after 7 and 14 days. Clinical improvement was defined as a reduction of at least 1 lameness grade or a combined reduction of at least 3 points in scores for pain during manipulation or palpation, joint swelling, joint circumference, and range of motion. RESULTS: Proportion of horses clinically improved on day 14 for the firocoxib group (104/123 [84.6%]) was not significantly different from the proportion for the phenylbutazone group (103/119 [86.6%]). Proportion of horses that were improved on day 14 was significantly greater for horses treated with firocoxib than for horses treated with phenylbutazone with regard to score for pain on manipulation or palpation (P = 0.028), joint circumference score (P = 0.026), and range of motion score (P = 0.012), but not for overall lameness score or joint swelling score. No direct treatment-related adverse effects were detected during the study. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that overall clinical efficacy of a paste formulation of firocoxib in horses with naturally occurring osteoarthritis was comparable to efficacy of a paste formulation of phenylbutazone.  相似文献   
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