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81.
Claudio Zaccone Valeria D’Orazio William Shotyk Teodoro M. Miano 《Journal of Soils and Sediments》2009,9(5):443-456
Background, aim, and scope
Fluorescence and UV-visible spectroscopies are simple but useful methods to characterize organic matter in the aqueous phase according to its aromatic nature and humification degree. Although there are several studies about porewater and water-extractable organic matter (WEOM) from peat, at present, no comparative investigations are available in the literature. Thus, the aim of the present study was to identify and compare chemical and spectroscopic features of porewaters and corresponding WEOM samples along a 105-cm undisturbed peat profile. 相似文献82.
Isabel Guadano Procesi Azzurra Carnio Federica Berrilli Margherita Montalbano Di Filippo Alessia Scarito Cristina Amoruso Marco Barni Marco Ruffini Giulia Barlozzari Manuela Scarpulla Claudio De Liberato 《Zoonoses and public health》2022,69(1):46-54
Giardia duodenalis is the most common intestinal protozoan in humans and animals worldwide, including eight morphologically identical assemblages, infecting pets, livestock, wildlife and human beings. Assemblages A and B are those with the higher zoonotic potential, and they have been detected in several mammals other than humans; the others (C to H) show a higher host specificity. Cats can harbour both the specific Assemblage F and the zoonotic ones A and B. Several studies have been carried out on G. duodenalis genotypes in cats; however, the role of this species in the epidemiology of giardiasis is still poorly understood. In this scenario, the present study carried out the detection and genetic characterization at sub-assemblage level of G. duodenalis from colony stray cats in central Italy. In the period 2018–2019, 133 cat faecal samples were analysed for the presence of G. duodenalis cysts by a direct immunofluorescence assay. Positive samples were subsequently subjected to molecular analyses for assemblage/sub-assemblage identification. Forty-seven samples (35.3%) were positive for G. duodenalis cysts by immunofluorescence. G. duodenalis DNA was amplified at SSU-rDNA locus from 39 isolates: 37 were positive for zoonotic Assemblage A and 2 showed a mixed infection (A + B). Positive results for the β-giardin gene were achieved for 25 isolates. Sequence analysis revealed 16 isolates belonging to Sub-assemblage AII and 8 to Sub-assemblage AIII. One isolate resulted as ambiguous AI/AIII. Large sequence variability at the sub-assemblage level was detected, with several double peaks and mutations, making complex a proper isolate allocation. When compared with previous studies, the 35.3% prevalence of G. duodenalis in cats reported in the present article was surprisingly high. Moreover, all positive cats resulted to be infected with zoonotic assemblages/sub-assemblages, thus indicating stray cats as a possible source of human giardiasis and highlighting the sanitary relevance of cat colonies in the study area. 相似文献
83.
Paola Superchi Claudio MazzoniPaola Zanardelli Chiara PiancastelliErnesto Mario Zambini Valentino BerettiAlberto Sabbioni 《Livestock Science》2013,157(1):372-377
To counteract the effects of perinatal hypoxia in piglets, the oral administration of caffeine to sows with induced parturition was evaluated. On day 113 of gestation 9 sows received 27 mg/kg body weight (BW) of caffeine mixed with 200 g of standard diet. The same amount of feed without the addition of caffeine was administered to 9 control sows. Additionally, on day 113 of gestation, all sows were treated by two injections in the perianal area of 1 mg of alfaprostol (at 8:00 am and 14:00 pm), and on the morning of farrowing by 14 IU of oxytocin in the perianal area. Caffeine did not affect BW of piglets and size of litters; however piglets from treated sows showed a higher capacity to adapt to extra-uterine life. Particularly, they showed a greater thermoregulatory ability (P<0.001) and a higher percentage of viability score≥7 compared to piglets from control sows (92% vs. 75%, respectively; P=0.030). Caffeine furthermore reduced the frequency of high serum biopterin values (>80 nmol/L) in piglets born from treated sows (P=0.001). In conclusion, the caffeine orally administered to sows with induced parturition showed a protective effect on the consequences of neonatal hypoxia in tissue ischemia–reperfusion injury in piglets. 相似文献
84.
Sydney Mukaratirwa Claudio Petterino Alys Bradley 《Journal of toxicologic pathology》2015,28(3):177-180
A single mass was found on the left submandibular salivary gland at necropsy of a 15-month-old male commercially bred laboratory Beagle dog from a control dose group from a repeat toxicity study. Microscopically, the mass was composed of a well-demarcated area of coagulative necrosis surrounded and separated from the normal salivary gland tissue by a thick fibrovascular capsule. Necrosis was admixed with areas of hemorrhage, fibrin, edema, fibrinoid necrosis of the vascular tunica media, and thrombosis of small and large vessels. Within the necrotic tissue, there was marked ductal hyperplasia, and squamous metaplasia of duct and acinar epithelium. The mass was diagnosed as necrotizing sialometaplasia of the submandibular gland. Hyperplastic ductal elements and squamous metaplasia can be mistaken microscopically with squamous cell carcinoma. Therefore, pathologists should be aware of this lesion as to avoid errors in the diagnosis of this benign pathologic condition. 相似文献
85.
86.
Laura Righetti Roberta Paris Claudio Ratti Matteo Calassanzio Chiara Onofri Davide Calzolari Wulf Menzel Dennis Knierim Gianmaria Magagnini Daniela Pacifico Gianpaolo Grassi 《European journal of plant pathology / European Foundation for Plant Pathology》2018,150(3):575-588
Interveinal chlorosis and leaf margin wrinkling are widespread symptoms of Cannabis sativa. They are traditionally attributed to the so-called hemp streak virus (HSV), but its existence has not been demonstrated yet. To our knowledge, no molecular investigation has so far been performed in order to identify the causal agent of this symptomatology, we therefore decided to use traditional and molecular virology techniques to better characterize symptoms and pursue the etiological agent. No pathogenic virus was found by using targeted PCR reactions and by RNA sequencing, whereas we were able to detect the Cannabis cryptic virus (CanCV) with both techniques. We, therefore, developed an RT-qPCR assay based on a CanCV-specific TaqMan probe and applied it to a wide range of symptomatic and symptomless plants, using a two-step (for quantification), or a one-step (for fast detection) protocol. Both symptoms and the virus were only shown to be transmitted vertically and did not pass via mechanical inoculation or grafting, though we could not find any cause-effect correlation between them. In fact, the virus was found in all the tested hemp samples, and its abundance varied greatly between different accessions and individuals, independently from the presence and severity of symptoms. The suggestion that hemp streak is caused by a virus is therefore questioned. Some abiotic stresses seem to play a role in triggering the symptoms but this aspect needs further investigation. For breeding purposes, a selection of parental plants based on the absence of symptoms proved to be efficient in containment of the disease. 相似文献
87.
Petterino C Bedin M Podestá G Ratto A 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(1):95-100
A 6-year-old intact female corn snake (Elaphe guttata guttata) was presented with a 3-week history of anorexia. Coelomic radiographs revealed a 9 x 4 cm soft tissue opacity suggestive of a right ovarian enlargement. The mass (9 x 5 x 4 cm) was surgically removed, and multiple smears from tissue sections were stained with Diff-Quik. Multiple tissue samples from the mass were collected and fixed in formalin. Cytologic specimens were moderately cellular and contained light pink amorphous background material. The cells were primarily spindle-shaped with moderate to marked anisocytosis and anisokaryosis. Cells sometimes were round to polygonal, and rarely were arranged in small clusters. Macrophages occasionally were observed. Histologic specimens consisted of a highly cellular mass composed of pleomorphic, spindle-shaped cells and, occasionally, round to polygonal cells arranged in irregular fascicles. The neoplastic cells were immunoreactive for cytokeratin (AE1/AE3), smooth muscle actin, and skeletal muscle actin, but did not stain for vimentin or desmin. On the basis of the morphologic and immunohistochemical results, a diagnosis of ovarian undifferentiated carcinoma was made. In this report, we describe the challenges of using immunohistochemistry to diagnose this uncommon type of tumor in reptiles. 相似文献
88.
Vila-Aiub MM Vidal RA Balbi MC Gundel PE Trucco F Ghersa CM 《Pest management science》2008,64(4):366-371
Herbicide resistance is an evolutionary event resulting from intense herbicide selection over genetically diverse weed populations. In South America, orchard, cereal and legume cropping systems show a strong dependence on glyphosate to control weeds. The goal of this report is to review the current knowledge on cases of evolved glyphosate-resistant weeds in South American agriculture. The first reports of glyphosate resistance include populations of highly diverse taxa (Lolium multiflorum Lam., Conyza bonariensis L., C. canadensis L.). In all instances, resistance evolution followed intense glyphosate use in fruit fields of Chile and Brazil. In fruit orchards from Colombia, Parthenium hysterophorus L. has shown the ability to withstand high glyphosate rates. The recent appearance of glyphosate-resistant Sorghum halepense L. and Euphorbia heterophylla L. in glyphosate-resistant soybean fields of Argentina and Brazil, respectively, is of major concern. The evolution of glyphosate resistance has clearly taken place in those agroecosystems where glyphosate exerts a strong and continuous selection pressure on weeds. The massive adoption of no-till practices together with the utilization of glyphosate-resistant soybean crops are factors encouraging increase in glyphosate use. This phenomenon has been more evident in Argentina and Brazil. The exclusive reliance on glyphosate as the main tool for weed management results in agroecosystems biologically more prone to glyphosate resistance evolution. 相似文献
89.
Kook PH Hagen R Willi B Ruetten M Venzin C 《Journal of Feline Medicine and Surgery》2010,12(12):978-981
Enteric duplication is a rare developmental malformation in people, dogs and cats. The purpose of the present report is to describe the first case of a rectal duplication cyst in a 7-year-old domestic shorthair cat presenting for acute constipation and tenesmus. On rectal palpation a spherical mass compressing the lumen of the rectum could be felt in the dorsal wall of the rectum. A computed tomography (CT) scan confirmed the presence of a well demarcated cystic lesion in the pelvic canal, dorsal to the rectum. The cyst was surgically removed via a perineal approach. No communication with the rectal lumen could be demonstrated. Histopathological examination was consistent with a rectal duplication cyst. Clinical signs resolved completely after excision of this conjoined non-communicating cystic rectal duplicate. 相似文献
90.
Cinthia Conforto Ignacio Cazón Franco D. Fernández Adriana Marinelli Claudio Oddino Alejandro M. Rago 《European journal of plant pathology / European Foundation for Plant Pathology》2013,137(4):663-666
In Argentina, Thecaphora frezii is the causal agent of peanut smut, causing severe yield losses in peanut growing areas. In this work sequence data of the large ribosomal subunit (28S rDNA) of four T. frezii specimens from different production regions are provided. A fragment of about 650 bp was amplified by PCR from each of the isolates analyzed. The analysis of the sequences demonstrated 100 % identity among the four specimens and 92–96.3 % identity with sequences of other species of Thecaphora. This is the first study on molecular sequences of this pathogen. 相似文献