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S Bettini

Publications and source records attributed to S Bettini.

At least 19 recordsLinked to original sources
PubMed1998

[Zooprophylaxis: old and new problems].

In the present note the authors report on the most important works which have examined the application of zooprophylaxis as a means for malaria control from the onset of this century to the present day. The method of zooprophylaxis has evolved throughout the years in close connection with other problems, undoubtedly more important in the history of malaria, which in the present paper are amply discussed. From the very beginning this subject was the object of heated debates by those who retained it a valid method of malaria control and those who denied its validity, among whom some of the most important Italian and foreign malariologists. The experiments of zooprophylaxis received most attention in the twenties, but, following the works of Missiroli and co-workers in the early thirties by which the varieties of the "complex maculipennis" were identified, the interest on zooprophylaxis was less heightened. It should be noted, however, that the increase of cattle, and especially land reclamation, reduced considerably malaria endemicity in northern Italy where zoophilic varieties were most prevalent. Recently, renewed interest on zooprophylaxis has been shown in Pakistan, where some experiments on the use of cattle have led to an unexpected increase of malaria transmission.

Animals↗
PubMed1991

Studies on mating plug of two sandfly species, Phlebotomus perniciosus and Phlebotomus papatasi (Diptera: Psychodidae).

A study was undertaken to interpret the nature and function of the "plug like formation" observed inside the spermathecae of many phlebotomine sandflies dissected during field surveys. Trials were carried out on two laboratory reared species, Phlebotomus perniciosus and P. papatasi. The results showed that the "plug like formation" is a true mating plug (MP) containing immotile sperms. Our studies showed also that the MP evolves differently according to the physiological state of the mated female. In blood-fed females, it persists 22-25 hrs post mating. Follows a period of 3-4 days in which the spermathecae acquire different form from that of the virgin spermathecae, but sperms are still undistinguishable. Active sperms appear only a few hours before oviposition. After oviposition, however, spermathecae are void as in the virgin female. Thus, during the complete gonotrophic cycle the spermathecae display five different forms: a) normal and void; b) showing MP; c) distended and yellowish, MP absent; d) active sperms present; e) normal and void. In unfed females, MP was observed to last for 6 days post copula. The results show also that MP is interfering with reinsemination.

Animals↗
PubMed1991

Philippo Bonanni and his "Micrographia curiosa".

In this introduction, a short biography of Philippo Bonanni and comments on his "Micrographia curiosa" are presented. P. Bonanni was the first naturalist to describe a phlebotomine sandfly. His work was published in 1691, and on the occasion of the Tricentenary of its publication, the "First International Symposium on Phlebotomine Sandflies" was organized.

Animals↗
PubMed1990

Leishmaniasis in Sardinia. IV. Epidemiological appraisal of cutaneous leishmaniasis and biochemical characterization of isolates.

Cutaneous leishmaniasis (CL) is endemic in Sardinia where 250 cases were reported from 1922 to 1988. The province of Sassari, in the north of the island, shows the highest number of cases. The vertical distribution of localities where cases had occurred is analysed and the age distribution of cases is given. Isolation of parasites was attempted in 12 cases, but successful growth of Leishmania was obtained from three cultures only. The stocks belonged to two different zymodemes of L. infantum: zymodeme Montpellier (ZMON) 24 and ZMON 24 MPI variant. The distribution of dermotropic L. infantum zymodemes in the Mediterranean area is discussed and the presence of a possible parasite reservoir is suggested.

Age Factors↗
PubMed1988

Leishmaniasis in Sardinia. III. Soil analysis of a breeding site of three species of sandflies.

Soil analysis was carried out on samples obtained from a breeding-site of the sandflies Phlebotomus perniciosus Newstead, P. perfiliewi perfiliewi Parrot and Sergentomyia minuta (Rondani) in Sardinia. Soil texture, pH, CaCo3, organic matter and water content showed no correlation with the number of sandflies that emerged from the places where soil samples were taken. It appears that pre-imaginal stages of these phlebotomine sandflies are associated with a relatively stable, cool and humid environment protected from sunshine and rain, rich in clay and in organic nitrogen.

Animals↗
PubMed1987

[An entomological survey in the focus of zoonotic cutaneous leishmaniasis (Leishmania major) of Sidi Bouzid (Tunisia) in 1985].

An entomological survey carried out in 1985 in the zoonotic cutaneous leishmaniasis foci of the Center of Tunisia (Sidi Bouzid Governorate), showed the presence of 7 phlebotomine species. Phlebotomus (P) papatasi, the most abundant species (84.6%), was essentially trapped in rodent burrows. Its anthropophily was demonstrated by man-baiting catch. The highest population density was observed during July and August, for P. papatasi. Its role in the transmission of Z. C. L. in Tunisia is discussed. P. perniciosus, less abundant (13.2%) was mostly trapped in animal resting places. Only few specimens of P. longieuspis, P. perfiliewi, Sergentomyia (S) minuta, S. antennata and S. dreyfussi were observed.

Animals↗
PubMed1986

Leishmaniasis in Sardinia: II. Natural infection of Phlebotomus perniciosus Newstead, 1911, by Leishmania infantum Nicolle, 1908, in the province of Cagliari.

Two promastigote-infected specimens of Phlebotomus perniciosus Newstead, 1911, were found in the province of Cagliari, Italy. The parasites from one specimen were successfully cultured in a hamster. The isolate was typed on 11 enzymes and shown to be identical with the reference strain of Leishmania infantum s.st. This is the first typing of a leishmanial organism from naturally infected P. perniciosus.

Animals↗
PubMed1986

Leishmaniasis in Sardinia. I. Observations on a larval breeding site of Phlebotomus perniciosus, Phlebotomus perfiliewi perfiliewi and Sergentomyia minuta (Diptera: Psychodidae) in the canine leishmaniasis focus of Soleminis (Cagliari).

During the summer-autumn period of 1983 and 1984, 1408 specimens of Phlebotomus perniciosus, 74 of P. perfiliewi perfiliewi and 35 of Sergentomyia minuta were caught in emergence traps in a locality close to the village of Soleminis, a canine leishmaniasis focus 15 km from Cagliari, Sardinia. All the flies were collected from a breeding site inside an abandoned cement building. Male flies were highly predominant for all three species. A few larvae of P. perniciosus were also collected from the same site. This is the first finding of an abundant larval breeding site of P. perniciosus.

Animals↗
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↗