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Maurizio Casiraghi

Publications and source records attributed to Maurizio Casiraghi.

9 recordsLinked to original sources
PubMed2006

A simple molecular method for discriminating common filarial nematodes of dogs (Canis familiaris).

Accurate diagnosis of canine filariosis is essential for choosing correct therapeutic approach. Therefore, reliable methods for discriminating among the different filarial infections in dogs are needed. The authors report simple and highly specific molecular methods that identify the three most common filarial nematodes of European dogs: Dirofilaria immitis, D. repens and Acanthocheilonema (syn. Dipetalonema) reconditum, based on (1) PCR amplifications of mitochondrial DNA (12S rDNA and coxI) with general filarial primers followed by digestion with restriction enzymes that generates band polymorphisms clearly discriminating the three species and (2) PCR amplifications with species-specific primers to support the restriction analysis, in particular in the case of multiple infections.

Animals↗
PubMed2006

Molecular phylogeny of Cryptocercus wood-roaches based on mitochondrial COII and 16S sequences, and chromosome numbers in Palearctic representatives.

Woodroaches of the genus Cryptocercus are subsocial and xylophagous cockroaches, distributed in North America and Asia. Studies on male chromosome number in Nearctic species have shown that diploid numbers vary from 2n=37 to 2n=47; numbers from Palearctic species were heretofore unknown. Two hypotheses have been proposed to explain the varying number of chromosomes among Nearctic species: the serial reduction hypothesis, and the parallel scenario. We performed phylogenetic analyses of the COII gene in these species and found evidence for the topology (47(45(43(39,37), which is congruent with the serial reduction hypothesis. We also determined chromosome numbers for the first time in Palearctic species, and found Cryptocercus primarius and Cryptocercus relictus to have relatively low chromosome numbers (2n=17-21) compared to their Nearctic relatives. Finally, our study determined the phylogenetic position of Cryptocercus primarius among other Asian taxa.

Animals↗
PubMed2005

The occurrence of strongylid nematodes in the epididymides of wood mice.

The recent discovery of a larval nematode in the epididymides of free-living wood mice (Apodemus sylvaticus) suggests a sexual transmission of these parasites. They have been placed within the bursate nematodes (order Strongylida) through 18S rDNA analysis, suggesting that they are undetermined metastrongyloid nematodes. The possibility that these parasites are transmitted sexually opens an intriguing field of research because sexually transmitted metazoan parasites are known to occur mainly in invertebrates, whereas in vertebrates sexually transmitted parasites are usually microparasites such as viruses, bacteria and protozoa.

Animals↗
PubMed2004

Mapping the presence of Wolbachia pipientis on the phylogeny of filarial nematodes: evidence for symbiont loss during evolution.

Wolbachia pipientis is a bacterial endosymbiont associated with arthropods and filarial nematodes. In filarial nematodes, W. pipientis has been shown to play an important role in the biology of the host and in the immuno-pathology of filariasis. Several species of filariae, including the most important parasites of humans and animals (e.g. Onchocerca volvulus, Wuchereria bancrofti and Dirofilaria immitis) have been shown to harbour these bacteria. Other filarial species, including an important rodent species (Acanthocheilonema viteae), which has been used as a model for the study of filariasis, do not appear to harbour these symbionts. There are still several open questions about the distribution of W. pipientis in filarial nematodes. Firstly the number of species examined is still limited. Secondly, it is not clear whether the absence of W. pipientis in negative species could represent an ancestral characteristic or the result of a secondary loss. Thirdly, several aspects of the phylogeny of filarial nematodes are still unclear and it is thus difficult to overlay the presence/absence of W. pipientis on a tree representing filarial evolution. Here we present the results of a PCR screening for W. pipientis in 16 species of filariae and related nematodes, representing different families/subfamilies. Evidence for the presence of W. pipientis is reported for five species examined for the first time (representing the genera Litomosoides, Litomosa and Dipetalonema); original results on the absence of this bacterium are reported for nine species; for the remaining two species, we have confirmed the absence of W. pipientis recently reported by other authors. In the positive species, the infecting W. pipientis bacteria have been identified through 16S rDNA gene sequence analysis. In addition to the screening for W. pipientis in 16 species, we have generated phylogenetic reconstructions based on mitochondrial gene sequences (12S rDNA; COI), including a total of 28 filarial species and related spirurid nematodes. The mapping of the presence/absence of W. pipientis on the trees generated indicates that these bacteria have possibly been lost during evolution along some lineages of filarial nematodes.

Animals↗
PubMed2004

Prevalence of Bartonella henselae in Italian stray cats: evaluation of serology to assess the risk of transmission of Bartonella to humans.

Bartonella henselae is the major etiological agent of cat scratch disease in humans. Cats act as the natural reservoir of B. henselae and can transmit the infection to humans by a bite or scratch. The prevalence of B. henselae in cat populations was evaluated by serological and bacteriological tests. A total of 769 stray cats from three urban and three rural areas in northern Italy were sampled between January 1999 and December 2000. The positive and the negative predictive values of serological tests with respect to bacteremic status were evaluated. Tests of a total of 140 cats (18%) resulted in detection of bacteremia. A total of 540 cats were tested by serology; 207 (38%) were seropositive. Of the 531 cats tested by both methods, the results for 65 (12.2%) showed both bacteremia detection and seropositivity. The molecular typing of the isolates showed that 20.6% of bacteremic cats were infected with B. henselae type I strain, 61.1% were infected with B. henselae type II, and 18.3% were coinfected with both. A statistically significant difference in antibody and bacteremia prevalences among geographical areas was detected. Statistical analysis showed no association between characteristics such as seroprevalence-bacteremic status, sex, general health status, and the presence of ectoparasites. The negative predictive value of serological test was 84.7%, and the positive predictive value was 31.8%. Receiving operator characteristic analysis of the data showed that serological tests had a low predictive value in relation to the bacteremic status of a cat; in surveys aimed at assessing the real risk of B. henselae infection in a human population, therefore, we suggest the use of blood culture as the reference test. Nevertheless, both blood culture assays and serological tests for Bartonella infection should be performed for a complete evaluation of the health status of cats.

Animals↗
PubMed2003

Molecular assay for the identification of Setaria tundra.

We report the molecular characterization of the amplification products obtained by specific PCR experiments aimed to identify the 5S ribosomal spacer of Setaria tundra specimens isolated from roe deer (Capreolus capreolus) in north Italy, which represent the first record of the parasite in this country. Three different fragments of approximately 400, 800, and 1200 bp (base pairs) are produced. Sequence analyses showed that all three fragments share a very high level of similarity to 5S spacer sequences of some Setaria species and other filariae present in genebank. Based on these sequences, we were able to design species-specific PCR primers for the precise identification of S. tundra.

Animals↗
PubMed2002

Full season efficacy of moxidectin microsphere sustained release formulation for the prevention of heartworm (Dirofilaria immitis) infection in dogs.

The authors report the efficacy of an injectable, moxidectin sustained release (SR) formulation for the prevention of canine heartworm infection in endemic areas in northern and central Italy. Three field trials were carried out on a total of 324 dogs. Two hundred forty-three dogs were treated with moxidectin SR 6 months apart and 81 dogs (positive controls) with moxidectin tablets given monthly for 5 consecutive months during the risk season each year throughout the study. Results of testing for microfilariae and circulating adult female antigens were negative for all the experimentally treated dogs at the 6, 7, 11 and 19 months after the last injection. No adverse reactions to moxidectin SR were observed but a moderate pain at palpation and swelling (5-6 cm) at the injection site after the first treatment. In the study areas, prevalence of Dirofilaria immitis infection calculated by testing dogs which had no preventive treatment in the previous transmission season ranged from 33 to 63%. This study confirms the efficacy and safety of injectable, moxidectin SR formulation in the prevention of heartworm infection in dogs and demonstrates that the prophylactic efficacy lasts for the full season and strongly suggests that the product gives 1-year protection.

Administration, Oral↗
PubMed2002

High reproductive skew in tropical hover wasps.

A plethora of recent models examines how genetic and environmental factors might influence partitioning of reproduction ('skew') in animal societies, but empirical data are sparse. We used three microsatellite loci to estimate skew on 13 nests of the Malaysian hover wasp, Liostenogaster flavolineata. Groups are small in L. flavolineata (1-10 females) and all females are capable of mating and laying eggs. Despite considerable variation between nests in parameters expected to influence skew, skew was uniformly high. On 11 of the 13 nests, all female eggs had been laid by a single dominant female. A second female had laid one to two out of 5-10 eggs respectively on the two remaining nests. A likelihood analysis suggested that on average, 90% of the male eggs had also been laid by the dominant. The slightly lower skew among male eggs might reflect the lower average relatedness of subordinates to male versus female offspring of the dominant. We suggest that high skew in L. flavolineata may result from strong ecological constraints and a relatively high probability that a subordinate will eventually inherit the dominant, egg-laying position.

Animals↗