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L Gradoni

Publications and source records attributed to L Gradoni.

At least 91 records · Page 5Linked to original sources
PubMed1984

[Status of the taxonomy of Leishmania from the Mediterranean basin].

Isoenzyme analysis, carried out on some hundreds of Leishmania isolates from the Mediterranean basin by specialized identification Centres, has provided new data on the taxonomy of this parasite in the area. Three complexes of zymodemes have been identified: L. infantum s.l., L. tropica s.l. and L. major s.l. L. infantum is the agent of human and canine visceral leishmaniasis and it is distributed throughout the Mediterranean area. Furthermore, this parasite is the only responsible for human cutaneous leishmaniasis in Central-Western Europe, including Italy. The distribution of L. tropica, agent of urban, or anthroponotic, cutaneous leishmaniasis, appears to be very limited, being restricted to Middle East, Tunisia and Greece. On the other hand, L. major, which causes rural, or zoonotic, cutaneous leishmaniasis, is widespread throughout North Africa and Middle East. In some countries, such as Tunisia and Israel, leishmaniases are caused by all the three complexes.

Africa, Northern↗
PubMed1983

Leishmaniasis in Tuscany (Italy): VII. Studies on the role of the black rat, Rattus rattus, in the epidemiology of visceral leishmaniasis.

The recent finding that four Leishmania isolates from Rattus rattus are enzymologically identical to L. infantum, aetiological agent of human and canine visceral leishmaniasis in the Mediterranean area, has stimulated further research on the role of R. rattus in the epidemiology of visceral leishmaniasis in Tuscany, Italy. The present work has led to the following results: (a) R. rattus experimentally infected with L. infantum displayed a general resistance to the parasite, even though it appeared that a very low number of amastigotes persisted in the animal for a long period; (b) Phlebotomus perniciosus and P. perfiliewi induced to feed on rats, with either a massive visceral infection or a subpatent immunodepressed infection, became infected, though in different proportions; (c) P. perniciosus and P. perfiliewi were readily attracted to, and fed on, the black rat in nature. These findings, together with those obtained earlier, strongly suggest that the black rat may be one of the wild reservoirs of L. infantum in the areas under study.

Animals↗
PubMed1983

Leishmaniasis in Tuscany (Italy): VIII. Human population response to leishmanin in the focus of Monte Argentario (Grosseto) and epidemiological evaluation.

A skin test survey carried out in the towns of Porto St. Stefano and Porto Ercole showed a total positivity rate of 15.3%. The progressive increase of positivity according to age was not uniform but similar for the two towns since the values concerning the last two age groups did not follow the general trend of the graph but were lower than expected. The possible causes of this phenomenon have been discussed. The absence of overt visceral leishmaniasis cases in recent years and the concomitant high prevalence of canine leishmaniasis have been considered in the light of the occurrence of infectious diseases and the increase of the nutritional levels in the local human population.

Animals↗
PubMed1983

Leishmaniasis in Sardinia: an introductory note.

Preliminary data on a project planned in Sardinia for the epidemiological study of leishmaniases are presented. Twenty-six dogs were found infected in the south-western part of the island. Nine isolates were successfully stabilated . In a canine leishmaniasis focus on the outskirts of Cagliari, Phlebotomus perniciosus was the predominant sandfly species (95%). In the same area, 28 specimens of Rattus norvegicus were trapped and their spleen homogenate was injected into hamsters. No Leishmania has yet been isolated.

Animals↗
PubMed1982

[Enzymatic typing of 11 strains of Leishmania isolated in mainland Italy from the visceral murine, canine and vulpine forms. Demonstration of an enzymatic variant in the fox (Vulpes vulpes) and the dog].

Enzyme typing by starch gel electrophoretic techniques was carried out on 11 Leishmania isolates from Italy in laboratories in Montpellier and London. The enzymes studied in the former were ME, G-6-PD, 6-PGD, PGM, PGI, GOT (= ASAT), MDH and IDH. In London slightly different procedures were used to examine ME, 6-PGD, PGM, PGI and ASAT. In addition, SOD, ALAT, NH, and MPI were studied. The combined data revealed that four Rattus rattus and four dogs were infected with classical L. infantum (zymodème 1). In addition, two other dogs and a fox were infected with an enzyme variant (zymodème 18) which differed in four of the 12 enzymes examined. These findings raise the question of the heterogeneity of the parasites causing visceral leishmaniasis.

Animals↗
PubMed1981

Leishmaniasis in Tuscany (Italy): (IV) An analysis of all recorded human cases.

Recent investigations on the distribution of human and canine leishmaniasis, and on the vectors and wild reservoirs of the disease in foci in Tuscany have stimulated a retrospective evaluation of human leishmaniasis of the whole region. From a study of the literature, of statistical reports (ISTAT) and of unpublished information, 77 cases of visceral leishmaniasis and 97 of cutaneous leishmaniasis have been analysed. From the case reports of both forms it appears that: (a) a higher incidence of cases occurred in restricted areas; (b) visceral and cutaneous leishmaniasis have been hypoendemic in Tuscany since the years of the earlier reports (1933 and 1936, respectively); (c) the number of infantile visceral cases was much higher in the period from 1933 to 1955 (84.5% of subjects in the 0-10 years age group) than in the subsequent years, 1956-75 (50.0%). The possible significance of the infantile and adult forms of visceral leishmaniasis in Tuscany is discussed, and the local data are compared with those of other regions.

Adolescent↗
PubMed1981

Leishmaniasis in Tuscany (Italy): VI. Canine leishmaniasis in the focus of Monte Argentario (Grosseto).

The results of a survey of canine leishmaniasis in the coastal focus of Monte Argentario (Tuscany, Italy) are reported. Of the 171 dogs examined, 41 (23.9%) were positive in the fluorescent antibody test (FAT), but only 12 (7.0%) were positive by microscopic observation of lymphatic ganglia. Of the 41 FAT positive dogs, 17 (10.0%) showed signs of the disease. The evolution of leishmaniasis over one year from the first examination showed that 88.0% of the dogs with signs died of the disease, and 36.0% of the asymptomatic dogs became patent or died; 52.0% of the asymptomatic dogs had apparently recovered. The prevalence of the disease, the geographical, age, sex and race distribution of cases, the evolution of leishmaniasis in dogs and FAT positivity are discussed.

Animals↗
PubMed1980

Leishmaniasis in Tuscany (Italy): (II) Leishmania from wild Rodentia and Carnivora in a human and canine leishmaniasis focus.

From April 1977 to February 1978, wild mammals were trapped in a focus of low leishmanial endemicity (Baccinello) in the Province of Grosseto (Tuscany, Italy). Spleen homogenates of the trapped animals were injected i.p. into hamsters, from which spleen biopsies were taken after 60 days and impression smears carefully observed for the presence of Leishmania. Positive spleens were subinoculated into hamsters. 404 animals of 12 species were trapped: 31 insectivores, 317 rodents and 56 carnivores. Black rats (Rattus rattus) and field mice (Apodemus sylvaticus) were the rodent species most frequently trapped--160 and 139 respectively--of which 143 and 134 respectively were tested in hamsters for Leishmania. 35 foxes (Vulpes vulpes) were caught, of which 16 were tested for Leishmania. Four hamsters were found infested with Leishmania. Three of them had been injected with spleen homogenates from R. rattus and one from V. vulpes although liver and spleen impression smears of all trapped animals were negative for Leishmania on direct microscopical examination. The significance of Leishmania infection in wild animals in the leishmanial focus of Baccinello is discussed.

Animal Population Groups↗
PubMed1980

[Filariasis in foxes in the Province of Grosseto].

A total of 350 foxes were examined in Grosseto province (Tuscany) and 68 (19,4%) have been found positive for microfilariae. The examination for adult forms has been carried out on a restricted number of foxes; one specimen of Dirofilaria repens has been found. The distribution of parasitosis and the presence of mosquito species, as possible vectors, has been discussed.

Animals↗
PubMedDate not supplied

Chemiluminescence activity in whole blood phagocytes of dogs naturally infected with Leishmania infantum.

Dogs are the domestic reservoir of Leishmania infantum, a vector-borne intracellular protozoan agent of human visceral leishmaniasis. The role of polymorphonuclear leukocytes (PMNs) in the immune defence against this parasite has been poorly studied. We have investigated the function of peripheral blood PMNs in naive beagle dogs that have been naturally exposed to phlebotomine vectors in an area highly endemic for canine leishmaniasis, and found infected by Leishmania at the end of the transmission season. Whole blood phagocyte oxidative metabolism was assessed by a rapid method that determines a luminol-amplified chemiluminescence (CL) emission. This was evaluated using either a soluble stimulant, phorbol mirystate acetate (PMA), or phagocytic stimuli, such as zymosan unopsonized (ZYM) or opsonized with autologous serum (OPZ). In blood samples taken 2 months after exposure to Leishmania transmission, data on CL emission revealed a significant decrease of reactive oxygen intermediates (ROI) production in the presence of both PMA and ZYM, compared with blood samples obtained from dogs before exposure. On the contrary, no variations in CL emission were detected in presence of OPZ. Our data indicate that immunological changes occur early in canine leishmaniasis and confirm that the role of PMNs and their products need to be clarified.

Animals↗
PubMedDate not supplied

Leishmaniasis in Sardinia. 5. Leishmanin reaction in the human population of a focus of low endemicity of canine leishmaniasis.

About half (640 subjects) of the population of Soleminis, a canine leishmaniasis focus 15 km north of Cagliari, Sardinia, was subjected to the leishmanin skin test. The total positive rate was 9.7%, and that of males was 15.5%. The age trend in the positive rate resembled a hyperbolic curve, with the 0-5 years age group rate being zero and the highest rate (39.3%) occurring in the 55-65 years age group. The Soleminis focus was classified as hypoendemic, with a prevalence of canine leishmaniasis of about 3%. Dog surveillance, land reclamation and changes in population habits during the last few decades are considered to be responsible for the reduction of transmission to man.

Adolescent↗