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81.
Previous studies from our group have demonstrated the high susceptibility of Toxoplasma gondii tachyzoites to the sterol analogues 22,26-azasterol and 24,25-(R,S)-epiminolanosterol. In this work we present data on testing in vitro three novel azasterols as potential agents for the treatment of toxoplasmosis. The three compounds inhibited parasite growth at micromolar concentrations, in a dose-dependent manner. Electron microscopy analysis of intracellular tachyzoites after treatment with the most effective compound showed drastic mitochondrion swelling associated with the appearance of an electron-lucent matrix and disrupted cristae. Parasite lysis also took place. The appearance of electron dense cytoplasmic structures similar to amylopectin granules distributed throughout the parasite suggests that azasterols might be inducing differentiation of those tachyzoites which were not lysed to the bradyzoite stage.  相似文献   
82.
Swimmer's itch is caused by the penetration of free‐swimming larvae of trematodes of the family Schistosomatidae in human skin. It is usually reported in people engaged in recreational water activities in freshwater bodies and in most of cases, it is provoked by bird schistosomes of the genus Trichobilharzia. In the summer 2017, many cases of dermatitis were recorded in people bathing in the waters of the Albano Lake (Rome, Italy) and a parasitological investigation was carried out in order to ascertain the causative agent of these cases. Snails of the family Lymnaeidae, natural intermediate hosts of bird schistosomes, were collected from lake shallow waters to detect the presence of trematodes of the genus Trichobilharzia. Pools of maximum 10 snails were placed in Petri dishes, and cercarial emergence was stimulated exposing snails to strong artificial light intensity at 25°C. Three hundred and thirty‐seven snails were collected and screened for the shedding of cercariae. Furcocercariae of the family Schistosomatidae, with a morphology overlapping that of the genus Trichobilharzia, were detected in seven Petri dishes. Assuming that in each positive Petri dish just one snail was shedding furcocercariae, the minimum infectious rate was 2.1%. Molecular analysis of furcocercariae allowed ascribing them to the species Trichobilharzia franki. Snails of the species Radix auricularia were identified as intermediate hosts of the parasite. This is the second record of T. franki causing cercarial dermatitis in Central Italy, the third in Italy. The 2017 was in Italy exceptionally warm and dry. Trematodes are sensitive to changes in temperature, being cercarial production and emission rates temperature dependent. Small increases in water temperature would speed up parasite development and transmission, leading to a manifold increase in cercarial emergence. Moreover, high temperatures raise chances to acquire the infection, due to increased time spent in water by people.  相似文献   
83.
Canine soft tissue sarcomas (STSs) are locally invasive mesenchymal neoplasms. Electrochemotherapy (ECT) is an antitumour local ablative treatment that uses electric pulses to enhance the intracellular delivery of cytotoxic drugs. The aim of this retrospective study was to review the current treatment for STSs and to evaluate the efficacy and safety of ECT with bleomycin in canine STSs. Fifty‐two dogs with 54 STSs were included. Three groups were arranged: (a) ECT alone, (b) intra‐operative ECT and (c) adjuvant ECT. Signalment, tumour size, location, histological grade and margins and ECT parameters were collected. Recurrence rate (RR) and disease‐free interval (DFI) were calculated. Treatment toxicity was assessed using a 6‐point scale. STSs were mostly located on limbs (77.8%). Median tumour size was 4.3 cm (range 0.4‐17.0 cm). Most STSs were grade I (47.7%) and II (50.0%), and histological margins were incomplete in 94.5% of cases. Two complete remissions, one partial remission and one stable disease were recorded in group 1. Group 2 and 3 were similar for tumour location, size and grade, histological margins, treatment toxicity, pulse frequency and voltage. Moreover, RR and DFI were similar between group 2 and 3 (23% and 25%, 81.5 and 243 days, respectively). Local toxicity post ECT was mild (score ≤ 2) in 66.7% of cases. Higher toxicity score was associated with higher pulse voltage (1200 vs 1000 V/cm) (P = 0.0473). ECT coupled with bleomycin resulted safe and efficient in tumour local control and should be considered as an option for treatment of canine STSs.  相似文献   
84.
A radiographical study of a cat mummy from the Egyptian collection of the National Archeological Museum in Parma, Italy was carried out in order to evaluate the content and to describe how cats were wrapped and mummified. The mummy contained the complete skeleton of a 4-5-month-old cat. Radiology revealed the position of the cat's body; it was wrapped to occupy the smallest space possible. In order to better position the cat, the ribs of the thorax were compressed cranio-caudally and the fore limbs were then positioned very close to the thorax. The hind limbs were flexed close to the lumbar spine and the tibio-tarsal joints were subluxated to allow the repositioning of the tarsal, metatarsal and phalanx bones cranio-caudally near the tibiae. A coccygeal vertebra was fractured in order to reposition the tail as close as possible to the body. Atlanto-occipital subluxation and a fracture/hole was present in the occipital region of the skull: whether this was made for draining skull contents as a mummification process and/or to euthanase the cat remains open for discussion.  相似文献   
85.
A flexible unmanned aerial vehicle for precision agriculture   总被引:1,自引:0,他引:1  
An unmanned aerial vehicle (??VIPtero??) was assembled and tested with the aim of developing a flexible and powerful tool for site-specific vineyard management. The system comprised a six-rotor aerial platform capable of flying autonomously to a predetermined point in space, and of a pitch and roll compensated multi-spectral camera for vegetation canopy reflectance recording. Before the flight campaign, the camera accuracy was evaluated against high resolution ground-based measurements, made with a field spectrometer. Then, ??VIPtero?? performed the flight in an experimental vineyard in Central Italy, acquiring 63 multi-spectral images during 10?min of flight completed almost autonomously. Images were analysed and classified vigour maps were produced based on normalized difference vegetation index. The resulting vigour maps showed clearly crop heterogeneity conditions, in good agreement with ground-based observations. The system provided very promising results that encourage its development as a tool for precision agriculture application in small crops.  相似文献   
86.
87.
Serological and molecular surveys were conducted to determine the occurrence of Bartonella henselae in domestic cats in Central Italy. Samples from 234 pet cats were tested for B. henselae antibodies by indirect immunofluorescence with 78 (33.3%) positive. A PCR assay specific for the Bartonella 16S rRNA gene was carried out on DNA samples extracted from blood of the 234 cats; 26 (11.1%) of the seropositive cats were positive. Two PCR protocols, which discriminate genotypes I and II of B. henselae, were performed on all DNA samples. Sixteen (6.8%) cats were infected by genotype I, 6 (2.5%) by genotype II, and two males (0.8%) by both genotypes. Two female (0.8%) cats which were Bartonella sp. PCR positive, gave negative results with the types I and II PCR. This protocol facilitates the direct and rapid detection of Bartonella DNA in feline blood samples, and differentiates B. henselae genotypes.  相似文献   
88.
Isolation and identification of mycobacteria from captive reptiles   总被引:1,自引:0,他引:1  
The occurrence of Mycobacterium species in clinically healthy pet reptiles was studied in Italy during the period 2004-2006. The feces samples of 223 animals were examined bacteriologically. Thirty-seven strains were isolated, in particular from 13/18 (72.2%) ophidians, 13/134 (9.7%) saurians and 11/71 (15.5%) chelonians. The isolates were classified, after HPLC analysis of bromophenacyl esters of cell wall mycolic acids, as Mycobacterium fortuitum (14 strains, 37.8%), Mycobacterium fortuitum-like (17, 45.9%), Mycobacterium peregrinum (4, 10.8%), and Mycobacterium chelonae (1, 2.7%). M. fortuitum was isolated from seven pythons, five saurians and two turtles; M. fortuitum-like from six saurians, six pythons and five turtles; M. peregrinum from four turtles; M. chelonae from one lizard. One isolate from an Iguana iguana could not be identified by HPLC analysis showing a previously unreported profile. Comparative 16S rDNA sequencing showed a low similarity with Mycobacterium triviale (97.2%) and Mycobacterium confluentis (97.1%). On the basis of such data the unidentified bacterium turned out to belong to a not yet described Mycobacterium species.  相似文献   
89.
BACKGROUND: Vascular endothelial growth factor (VEGF) is a regulator of angiogenesis and vascular permeability. In human patients with meningiomas, increased VEGF expression is predictive of postsurgical recurrence. The objectives of this study were to evaluate VEGF expression in canine intracranial meningiomas and to determine whether an association between VEGF expression and patient survival existed. METHODOLOGY: Tumor tissue from 17 dogs with histologically confirmed intracranial meningiomas was obtained surgically. All dogs then were treated with radiotherapy. Immunohistochemistry was performed on 5-microm sections of paraffin-embedded tumor tissue with rabbit anti-human VEGF polyclonal antibody. The extent, intensity, and distribution of VEGF staining for each section were assessed with light microscopy by means of a semiquantitative scale. Survival was analyzed by the Kaplan-Meier procedure. Survival rates among groups were compared by log-rank tests with the significance set at P < or = .05. FINDINGS: VEGF expression was detected in all tumors, with >50% of cells staining positively in tissues from 15/17 dogs. Shorter survival times were associated with greater VEGF expression (P = .01). CONCLUSIONS: VEGF expression can be measured in canine intracranial meningiomas and may be associated with poor outcome. SIGNIFICANCE: The extent of VEGF expression in canine intracranial meningiomas may be used as a prognostic marker and suggests a potential future target for therapy.  相似文献   
90.
The antimicrobial activity of leaf and callus extracts of Melia azedarach was tested on in vitro shoot cultures of the peach rootstoch ‘MRS 2/5’ (Prunus cerasifera × Prunus spinosa) that were heavily contaminated with Sphingomonas paucimobilis (Sp) and Bacillus circulans (Bc). The extracts were filter-sterilised and added at 0%, 1%, 5%, 10% and 20% to a modified Murashige and Skoog proliferation medium previously autoclave-sterilised. Up to about 17% shoots died with 10–20% extract, except for Sp-contaminated shoots, whose survival was reduced to 50% after treatment with 20% extract. No shoots died with 1% to 5% supplement. The undiluted leaf extract showed bactericidal activity on plated Sp and Bc isolates. The homogenates of shoots randomly collected from treated cultures were processed for bacterial colony counting. Thus the 10% supplement was the best treatment for ridding Bc-contaminated cultures of bacteria (although 5% had a similar bactericidal effect), and allowing shoot growth and proliferation comparable to controls at the fifth subculture on a standard medium, while 20% extract was needed to eliminate Sp, and could induce higher growth and proliferation rates in surviving shoots than in untreated cultures. Callus extract was ineffective. The bactericidal activity of the leaf extract seemed attributable to a synergistic effect of azadirachtin with other unidentified compounds present in the extract.  相似文献   
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