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G Savini

Publications and source records attributed to G Savini.

At least 19 recordsLinked to original sources
PubMed2006

Differentiation between field and vaccine strain of bluetongue virus serotype 16.

In August 2000, bluetongue virus (BTV) appeared for the first time in Sardinia and, since then, the infection spread across Sicily and into the mainland of Italy involving at the beginning serotypes 2 and 9 and then, from 2002, 4 and 16. To reduce direct losses due to disease and indirect losses due to new serotype circulation, the 2004 Italian vaccination campaign included the modified-live vaccines against BTV-4 and 16 produced by Onderstepoort Biological Product (OBP), South Africa. Few months after the end of the campaign, BTV-16 was reported broadly in the country and the need of differentiating field from the BTV-16 vaccine isolate became crucial. In this study, the gene segments 2, 5, 6 and 10 of both the Italian and vaccine BTV-16 strains were sequenced and their molecular relationship determined. As sequences of segment 5 were those showing the highest differences (17.3%), it was possible to develop a new diagnostic tool able to distinguish the Italian BTV-16 NS1 gene from that of the homologous vaccine strain. The procedure based on the use of a RT-PCR and the subsequent sequencing of the amplified product showed a high degree of sensitivity and specificity when samples from either BTV-16 vaccinated or infected sheep were tested.

Animals↗
PubMed2005

Bluetongue virus isolations from midges belonging to the Obsoletus complex (Culicoides, Diptera: Ceratopogonidae) in Italy.

Between July and September 2002 there were outbreaks of bluetongue on three sheep holdings in the communities of San Gregorio Magno (Salerno, Campania), Laviano (Salerno, Campania) and Carpino (Foggia, Puglia), and the involvement of bluetongue virus (btv) was confirmed serologically and virologically. The mortality rate was at least 11 per cent and involved btv serotype 2 (btv-2) and serotype 9 (btv-9). These holdings were also surveyed for the Culicoides (Diptera: Ceratopogonidae) vectors; approximately 10,000 midges belonging to 15 species were captured, but they did not include a single specimen of the classical Afro-Asiatic bluetongue vector, Culicoides imicola. Species belonging to the Obsoletus complex dominated the light-trap collections, and Culicoides obsoletus Meigen, Culicoides scoticus Downes and Kettle and Culicoides dewulfi Goetghebuer constituted 90 per cent of all the Culicoides species captured. Fifty-six pools of the Obsoletus complex (excluding C dewulfi), each containing 100 individual midges and containing only parous and gravid females, were assayed for virus. btv-2 was isolated from three pools from San Gregorio Magno and Carpino, and btv-9 was isolated from one pool from Laviano. These results indicate that a species other than C imicola is involved in the current re-emergence of bluetongue in the Mediterranean Basin, but whether it is C obsoletus sensu stricto or C scoticus, or both, is uncertain.

Animals↗
PubMed2005

VP2-segment sequence analysis of some isolates of bluetongue virus recovered in the Mediterranean basin during the 1998-2003 outbreak.

The complete nucleotide sequences of the VP2 segments of bluetongue virus (BTV) isolates recovered from Italy, Greece and Israel, from 1998 to 2003, were determined. Phylogenetic analysis of these sequences, those from related viruses and the South African vaccine strains, were used to determine the probable geographic origin of BTV incursions into Italy. Results indicated that viruses from each of the four serotypes isolated in Italy (2, 4, 9 and 16) possibly had a different origin. Analysis of the bluetongue virus serotype 2 (BTV-2) isolates gave evidence that this serotype probably moved from Tunisia. BTV-4 results showed probable incursion from the southwest and not from Greece or Israel. BTV-9 isolates clearly have an eastern origin (most probably Greece), whereas BTV-16 isolates are indistinguishable from the BTV-16 live attenuated vaccine strain. The phylogenetic findings were supported by polyacrylamide gel electrophoresis (PAGE) analysis of the complete amplified genome of each isolate except for BTV-16 Italian field isolate, which showed a slightly different PAGE profile. A combination of the complete VP2 sequencing and PAGE analysis of complete genomes, allowed not only phylogenetic analysis, but also vaccine detection and assessment of reassortment events.

Amino Acid Sequence↗
PubMed2005

Correlation between retinal nerve fibre layer thickness and optic nerve head size: an optical coherence tomography study.

AIM: To investigate the correlation between retinal nerve fibre layer (RNFL) thickness and optic nerve head (ONH) size in normal white subjects by means of optical coherence tomography (OCT). METHODS: 54 eyes of 54 healthy subjects aged between 15 and 54 underwent peripapillary RNFL thickness measurement by a series of three circular scans with a 3.4 mm diameter (Stratus OCT, RNFL Thickness 3.4 acquisition protocol). ONH analysis was performed by means of six radial scans centred on the optic disc (Stratus OCT, Fast Optic Disc acquisition protocol). The mean RNFL values were correlated with the data obtained by ONH analysis. RESULTS: The superior, nasal, and inferior quadrant RNFL thickness showed a significant correlation with the optic disc area (R = 0.3822, p = 0.0043), (R = 0.3024, p = 0.026), (R = 0.4048, p = 0.0024) and the horizontal disc diameter (R = 0.2971, p = 0.0291), (R = 0.2752, p = 0.044), (R = 0.3970, p = 0.003). The superior and inferior quadrant RNFL thickness was also positively correlated with the vertical disc diameter (R = 0.3774, p = 0.0049), (R = 0.2793, p = 0.0408). A significant correlation was observed between the 360 degrees average RNFL thickness and the optic disc area and the vertical and horizontal disc diameters of the ONH (R = 0.4985, p = 0.0001), (R = 0.4454, p = 0.0007), (R = 0.4301, p = 0.0012). CONCLUSIONS: RNFL thickness measurements obtained by Stratus OCT increased significantly with an increase in optic disc size. It is not clear if eyes with large ONHs show a thicker RNFL as a result of an increased amount of nerve fibres or to the shorter distance between the circular scan and the optic disc edge.

Adolescent↗
PubMed2003

Role of the cholinergic system and of apamin-sensitive Ca2+-activated K+ channels on rabbit jejunum spontaneous activity and on the inhibitory effects of adrenoceptor agonists.

1. One reason why rabbit jejunum is suitable for studying the mechanisms underlying the actions of the various neurotransmitters and their interactions is its spontaneous motility. The main regulator of spontaneous motility is the cholinergic system. How the cholinergic system regulates the spontaneous activity in the rabbit jejunum and how it affects the inhibitory action of alpha- and beta-adrenoceptor agonists remains unclear. 2. We studied the influence of the cholinergic system and apamin-sensitive Ca2+-activated K+ channels on spontaneous contractions in the rabbit jejunum and on the inhibitory effects of alpha1- and beta-adrenoceptor agonists. 3. In naïve tissues, atropine (ATR, 7.4 x 10(-8) m) and tetrodotoxin (8 x 10(-8) m) almost completely inhibited - to a similar extent - the amplitude of spontaneous activity. Despite the presence of ATR or TDX, tissue contraction gradually recovered to about 50% of the baseline amplitude within 5-10 min. When ATR or TDX, respectively, were added to the TDX- or ATR-treated tissues, the recovered activity decreased weakly but significantly. After washout and a 45-min rest the contraction amplitude returned to baseline values. A further exposure to ATR or TDX reduced the contraction to a level significantly lower than the one obtained after TDX or ATR added 5 min after ATR or TDX, respectively. In preparations prestimulated for 10 min with acetylcholine (ACh), ATR abolished the TDX-resistant recovered spontaneous activity. 4. Adrenaline (ADR, 0.5-5 x 10(-7) m) and phenylephrine (PHE, 1-10 x 10(-7) m) inhibited tissue motility in naïve and in ATR- and in TDX-exposed preparations. But whereas in naïve preparations the alpha1-adrenoceptor antagonists completely antagonized inhibition induced by both drugs, in ATR- and TDX-exposed tissues they did so only partially for ADR. Agonist-induced inhibition had a rapid onset but rapidly faded; pendular movements took significantly longer to recover in ATR- and TDX-treated tissues than in naïve tissues. In tissues exposed for 2 min to ADR (0.5-5 x 10(-7) m) or PHE (1-10 x 10(-7) m), washout or addition of alpha1-adrenoceptor antagonists caused an immediate short-lasting increase in contraction amplitude. 5. Apamin (APAM, 5 x 10(-9) m) caused a rapid and persistent increase in the amplitude of contractions. It also blocked the inhibitory responses to ADR and PHE, and removed washout-induced contractions. The APAM-induced increase in the contraction amplitude correlated with the increase obtained by washing out ADR or PHE. 6. Isoprenaline (at concentrations up to 2.8 x 10(-7) m) produced no inhibitory response in naïve tissues, but it invariably blocked (at a concentration of 0.7 x 10(-7) m) the recovered spontaneous activity (and sometimes depressed muscletone) in tissues exposed to ATR or TDX. Neither propranolol (3.4 x 10(-7) m) nor APAM (5 x 10(-9) m) counteracted these inhibitory effects. 7. These results indicate that spontaneous motility in the rabbit jejunum is predominantly mediated by neuronal release of ACh and by some other unidentified neuronal activity. Released ACh inhibits myogenic activity and strongly antagonizes beta-adrenoceptor-induced APAM-insensitive inhibition but leaves alpha1 agonist-induced APAM-sensitive inhibition unchanged.

Acetylcholine↗
PubMed2000

Neosporosis in water buffalo (Bubalus bubalis) in Southern Italy.

A study was carried on 1377 water buffalo serum samples from 50 farms in southern Italy to test the presence of Neospora caninum antibodies by indirect fluorescence antibody test (IFAT). Rabbit anti-buffalo immunoglobulins conjugated to fluorescein were used in the test. Fluorescence in sera dilutions above 1:200 was considered as indicative of the presence of N. caninum antibodies. The overall prevalence of infection in the animals was 34.6%. The prevalence increased in relation to the age of subjects and most of the herds examined (82%) were found infected. In two farms abortions and neurological signs were reported. No suppurative inflammatory lesions were seen, but few protozoan-like cysts were observed on foetal tissues by histology.

Abortion, Veterinary↗
PubMed1999

Tick-borne diseases in ruminants of Central and Southern Italy: epidemiology and case reports.

Sera and blood from cattle and sheep were examined for the presence of Babesia and Theileria spp by microscopy and serology at the Parasitology Department of the Istituto Zooprofilattico Sperimentale of Abruzzo and Molise (IZSAM). Of the 47 bovine herds (323 animals) tested, 15 were found positive for Babesia bigemina and 1 for Babesia bovis. Two outbreaks occurred, one caused by B. bigemina and one by B. bovis. The B. bigemina outbreak occurred in Abruzzo and has been followed for two years. The isolate of B. bigemina was very pathogenic leading to the death of two cows out of 57. The vector responsible of the transmission appeared to be Rhipicephalus bursa. Parasites were observed in the erythrocytes for 30 days whereas sera were positive to indirect immunofluorescence (IFA) for at least one year. The B. bovis outbreak occurred in the province of Mantova (Northern Italy) in a group of 70 beef cattle imported from France. The infection resulted in the death of 5 animals and severe illness in another 6. In contrast with what occurred for Babesia infection, no clinical cases were recorded in cattle when species of Theileria were detected by microscopy. Of the 24 bovine herds (252 animals) tested for Theileria, 21 were found positive for the T. "sergenti"/buffeli/orientalis group. Single and mixed infection of T. "sergenti" and T. buffeli/orientalis were detected in herds of cross-bred cattle from Abruzzo and Marche. The parasites were identified by using a polymerase chain reaction which amplified DNA encoding p32/34. Most of the collected ticks (90%) were adults of R. bursa whereas the others were adults of Hyalomma detritum. During the period the animals have been observed (18 months), no clinical cases have been recorded and no associations have been found between blood abnormalities and animals found infected with Theileria. Prevalences of subclinically infected carriers increased from February till December (95.4%) even if the animals were indoors and no ticks were present. The prevalence then dropped dramatically six months later (76.7%). In calves less than 1 year old, the prevalence of infection significantly (p<0.05) increased with age, however intraerythrocytic stages of Theileria were found in the blood of three newborn calves (<7 days of age). Of the 18 ovine flocks tested for Babesia spp. (150 animals examined), 1 was positive for B. ovis and 2 for B. motasi. B. motasi infection was not associated with symptoms, while an outbreak of babesiosis caused by B. ovis occurred in Abruzzo. The infection resulted in the death of 3 animals (0.75% of the flock), two rams (20% of the total number) and a ewe, and severe illness in another 5 ewes (2% of the flock). Specimens of R. bursa and R. turanicus were collected from the infected animals. Of the 18 flocks (150 animals) examined, 12 were microscopically positive for Theileria spp. No clinical cases were recorded and identification at species level was not possible on the basis of morphological criteria. The prevalence distribution of infected herds and infected animals within herds and flocks have been calculated by a Monte Carlo simulation model, running 10,000 iterations. The most likely levels of prevalence of infected herds and infected animals within herds found for the species observed were as follows: 20% for B. bigemina with a prevalence within herd of 27%, 11% for B. bovis (18% within herd), 10% for Babesia ovis (19% within herd), 10% for B. motasi (17.5% within herd), 63% for Theileria in cattle (66% within herd) and 51% for Theileria in sheep (55% within herd).

Animals↗
PubMed1998

Tamoxifen retinopathy: does it really exist?

BACKGROUND: Tamoxifen retinopathy is known to be an adverse effect of high-dose tamoxifen treatment. Evidence of ocular toxicity at lower doses is less convincing: the aim of this study was to assess the prevalence of the above-mentioned retinopathy in a population treated with low-dose tamoxifen. METHODS: One hundred and twenty-nine women treated with low-dose tamoxifen (20 mg/day) were examined. Visual acuity measurement, slit-lamp biomicroscopy and fundus examination were performed. Patients were reexamined after 6-12 months. RESULTS: Refractile retinal opacities, similar to those previously described as tamoxifen retinopathy, were observed in four patients (prevalence 3.1%; mean duration of therapy 806 days). None of them revealed corneal opacities, papillary and/or macular edema, or visual impairment. The ophthalmoscopic aspect did not change after a mean follow-up of 215 days, although one of these patients had interrupted tamoxifen intake. Statistical analysis (Student's t-test) did not reveal any difference between patients with and those without refractile retinal opacities as far as age, treatment duration and ERG values were concerned. An early hyperfluorescence, reminescent of cuticular drusen, was demonstrated by fluorescein angiography in all four cases. CONCLUSIONS: The present study would seem to confirm that low-dose tamoxifen may induce retinal toxicity in a low proportion of patients, but we cannot be certain that the refractile retinal opacities observed are really caused by tamoxifen, as differentiation from age-related macular degeneration with cuticular drusen appears nearly impossible.

Adult↗
PubMed1998

Monomanual pupil stretcher.

The monomanual pupil stretcher is a new instrument that allows the authors to easily, quickly, and safely stretch the pupil. The specific features of the hooks allow pupil stretching to be performed in a single maneuver and in a more effective manner.

Equipment Design↗
PubMed1997

Excystation rates and infectivity of sporocysts of Sarcocystis cruzi exposed to different treatments and storages.

The effect of some chemical and anatomical factors on the excystability and infectivity in cell culture of sporocysts of Sarcocystis cruzi was investigated. A significantly (P < 0.001) higher excystation rate (ER) occurred when sodium bicarbonate was added to the excysting fluid at concentrations between 0.075 and 0.3 M. Sporocysts collected from different dogs had different ER. In contrast, although not uniformly distributed along the intestinal lumen, the sporocysts collected from the different tracts of the intestine showed similar ER. The period of storage did not affect the excystability of the sporocysts; however, it influenced the pattern of growth of the sporozoites in cell culture. Sporozoites excysted from sporocysts stored for approximately 2 years grew slower and produced significantly fewer merozoites compared to those excysted from sporocysts stored for 5-7 months.

Animals↗
PubMed1997

Sensitivities and specificities of two ELISA tests for detecting infection with Sarcocystis in cattle of Western Australia.

The accuracies of two ELISAs, one using antigen from merozoites of S. cruzi grown in vitro and the other using antigen from cystozoites of S. cruzi, for detecting infection of cattle with Sarcocystis, were evaluated by testing the sera of 303 cattle from 36 Western Australian herds. The results were compared with those obtained by digestion of oesophageal samples collected from the same animals. A similar proportion of infected animals were detected by the three methods. The sensitivity of the assays for detecting infected cattle was comparable (98 and 95% for the assay using antigen from merozoites and cystozoites, respectively), however the specificity (97%) of the assay which used antigen derived from merozoites was significantly higher (P < 0.001) than that (84%) which used antigen from cystozoites. When herds which had at least five animals sampled were considered, the same infected and non-infected herds were detected by the ELISA employing antigen from merozoites and the digestion methods (sensitivity and specificity of 100%). The sensitivity and specificity of the assay using cystozoite antigen were 100 and 67%, respectively. The kappa values for agreement beyond chance between the two ELISAs were calculated as 78% for the animal-based data and 72.5% for the herd-based data. We conclude that because of the high sensitivity and specificity of the ELISA using antigen derived from merozoites, this assay would be a useful and reliable tool for general sero-epidemiological studies into infection with Sarcocystis.

Abattoirs↗
PubMed1997

Class-specific antibody responses in cattle following experimental challenge with sporocysts or merozoites of Sarcocystis cruzi.

An ELISA using antigen produced from merozoites of Sarcocystis cruzi was developed to monitor specific IgM and IgG antibody, following challenge of cattle with either merozoites or sporocysts of S. cruzi. This assay was compared with an ELISA using antigen produced from the cystozoite stage of the parasite. Both ELISAs were able to detect significant increases in levels of circulating IgM and IgG antibodies against Sarcocystis in all challenged cows; however, the magnitude of the titres was greater in the ELISA which used the antigen derived from the merozoites. This immunoassay also detected increases in the levels of IgG earlier than did the assay using antigen derived from cystozoites of S. cruzi. Since this rise coincided with the presence of clinical signs, and was persistent for several weeks, the IgG-ELISA using antigen derived from merozoites appears to be suitable for the diagnosis of acute sarcocystiosis in cattle. Furthermore, since significant increases in the levels of circulating IgM and IgG antibodies against Sarcocystis were detected in the cows infected with merozoites of S. cruzi, it is evident that merozoites of S. cruzi cultured in vitro maintain their capability to replicate in the natural intermediate host.

Animals↗
PubMed1996

Viability of the sporocysts of Sarcocystis cruzi after exposure to different temperatures and relative humidities.

The effect of temperature and relative humidity (RH) on the survival of sporocysts of S. cruzi were investigated in vitro. Under all experimental conditions (temperature of 4 degrees C, 37 degrees C, or room temperature; RH of 18%, 75%, or 100%) some sporozoites retained their viability to excyst for at least 90 days. The best conditions for survival were 4 degrees C at 100% RH (more than 240 days) and 37 degrees C at 18% RH (more than 180 days). Sporocysts maintained at room temperature at all humidities had the lowest level of survival. It is concluded that sporocysts of S. cruzi are able to survive in most environments for several months and that the fluctuation of the daily ambient temperature is likely to influence the viability of the sporocysts.

Animals↗
PubMed1996

Studies on pathogenesis, tissue infection and congenital transmission in cows experimentally infected with Sarcocystis cruzi by various routes.

A group of nine cows, naturally infected with Sarcocystis, were challenged with Sarcocystis cruzi: three intrarumenally with sporocysts, two intrarumenally with water (controls), two intravenously with merozoites grown in vitro and two intravenously with saline solution (controls). The animals intrarumenally challenged with sporocysts developed acute sarcocystiosis and produced stillborn calves, whereas those intravenously challenged with merozoites suffered from subclinical sarcocystiosis with premature births. No parasites were found in calves from cows challenged with sporocysts; however, a meront of Sarcocystis was found within a macrophage in the cerebrospinal fluid of a calf from a cow intravenously inoculated with merozoites of S. cruzi. This is the first time that merozoites of S. cruzi grown in vitro have been demonstrated to retain the ability to infect their natural intermediate host and complete their life cycle.

Animals↗
PubMed1994

Evaluation of a serological test system for the diagnosis of Sarcocystis cruzi infection in cattle using S. cruzi merozoite antigen.

Fifty serum samples were examined by enzyme-linked immunosorbent assay (ELISA) for antibodies directed against crude antigens isolated from cystozoites and merozoites of Sarcocystis cruzi and Sarcocystis tenella/Sarcocystis arieticanis and merozoites of Toxoplasma gondii. Of these 50 samples, 25 were from cattle originating from an area where the prevalence of S. cruzi was found to be very low (9%) and in which no cystozoites were detected, and 25 were from cattle which were found by a digestion method to be heavily infected with S. cruzi. A very high correlation was observed between the parasitological data and the results obtained from the serological assays which used antigens from either cystozoites or merozoites of S. cruzi. The assay using the antigen derived from merozoites provided the best result for discriminating infected and non-infected animals. There was some cross-reactivity between the antigen derived from cystozoites of heterologous species of Sarcocystis and S. cruzi antibodies, and some cross-reactivity between antigen of T. gondii and antibodies to S. cruzi. The reproducibility of the assays was found to be high and similar results were observed when the sera were tested on two separate occasions. The unpurified S. cruzi merozoite antigen produced in vitro is relatively accurate in discriminating positive and negative animals and may be used for diagnosis in economically important hosts such as cattle and sheep.

Animals↗