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G Saccone

Publications and source records attributed to G Saccone.

13 recordsLinked to original sources

A new Minos vector for eye-specific expression of white+ marker in Ceratitis capitata and in distantly related dipteran species.

The genetic transformation of insects by transposable elements is based on the use of selectable genetic markers required to identify transgenic individuals. Conserved regulatory sequences can be used to develop single constructs capable of adequate expression of a marker, across a range of different species. We present evidence that the Drosophila GBS regulatory element (Glass-binding site), derived from the Rh1 rhodopsin gene, is able to drive in vivo eye-specific expression of a Ccwhite+ transgene in the Mediterranean fruitfly Ceratitis capitata. The Ceratitis lineage diverged from that of Drosophila approximately 120 Myr ago. As the GBS regulatory sequence seems to be partially conserved in the more distantly related dipteran species Anopheles gambiae (250 Myr), we propose that the GBS may be widely useful for driving eye-specific expression in a wide range of dipteran species.

Animals↗

Sex determination in flies, fruitflies and butterflies.

Sex determination mechanisms, differing in their modality, are widely represented in all the various animal taxa, even at the intraspecific level. Within the highly diversified Class Insecta, Drosophila has been used to unravel the mechanistic molecular and genetic interactions that are involved in sex determination. Indeed, the molecularly characterized genes of the Drosophila sex determination hierarchy X:A > Sxl > tra > dsx have been fruitful starting points in the cloning of homologous genes from other insect species. This cascade seems to control sex determination in all Drosophila species. However, no sex-specific regulatory Sxl homologues have been isolated from the Mediterranean fruitfly (medfly), Ceratitis capitata, the housefly, Musca domestica, Chrysomya rufifacies nor from the distantly related phorid fly Megaselia scalaris. Moreover, all these other species use primary signals different from the intricate X:A counting system of Drosophila. However, dsx homologues isolated from these and other dipteran species as well as from the silkmoth, Bombyx mori, share a conserved sex-specific regulation based on alternative splicing. An understanding of the sex determination mechanisms in insects that are of agricultural or public health importance may help in the development of improved methods for their control using the sterile insect technique.

Alternative Splicing↗

Genomic organization and characterization of the white locus of the Mediterranean fruitfly, Ceratitis capitata.

An approximately 14-kb region of genomic DNA encoding the wild-type white eye (w+) color gene from the medfly, Ceratitis capitata has been cloned and characterized at the molecular level. Comparison of the intron-exon organization of this locus among several dipteran insects reveals distinct organizational patterns that are consistent with the phylogenetic relationships of these flies and the dendrogram of the predicted primary amino acid sequence of the white loci. An examination of w+ expression during medfly development has been carried out, displaying overall similarity to corresponding studies for white gene homologues in Drosophila melanogaster and other insects. Interestingly, we have detected two phenotypically neutral allelic forms of the locus that have arisen as the result of an apparently novel insertion or deletion event located in the large first intron of the medfly white locus. Cloning and sequencing of two mutant white alleles, w1 and w2, from the we,wp and M245 strains, respectively, indicate that the mutant conditions in these strains are the result of independent events--a frameshift mutation in exon 6 for w1 and a deletion including a large part of exon 2 in the case of w2.

Alleles↗

Additional beneficial effects of canrenoate in patients with anterior myocardial infarction on ACE-inhibitor treatment. A pilot study.

BACKGROUND: Recent evidence suggests that, via the mineralocorticoid receptors present in cardiovascular tissues, aldosterone exerts profibrotic effects, and that partial aldosterone escape occurs during ACE-inhibitor treatment. METHODS: A double-blind, randomized study was performed in order to evaluate the feasibility, tolerability, and the effects of the administration of 25 mg/day of canrenoate plus captopril versus captopril alone to patients with anterior acute myocardial infarction (AMI) unsuitable for or not receiving thrombolytic treatment and to patients in whom such treatment resulted or did not result in reperfusion. One hundred eighty-seven patients with anterior AMI were included in the present study. In all cases serum creatinine concentrations and serum K concentrations were < 2.0 mg/dl and < 5.5 mmol/l respectively. The patients were randomized in two groups: the canrenoate group included 94 patients who received captopril and 25 mg i.v. of canrenoate (1 mg/hour for the first 72 hours and then orally 25 mg/day) whereas the placebo group (93 patients) received captopril and placebo. On admission and on days 10, 90 and 180 all patients underwent echocardiography in order to determine the end-systolic volume (ESV), the ejection fraction (EF), the end-diastolic diameter, the E/A ratio, the E deceleration time as well as the isovolumetric relaxation time (IVRT) and the E and A peak velocities. RESULTS: Unreperfused patients did not show patency of the infarct-related artery whereas in reperfused patients this vessel was patent (7-10 days after AMI). The two groups were similar in age, sex, incidence of diabetes, smoking habits, hypertension, creatine kinase enzymatic peak, adjuvant therapy, baseline EF, ESV, and incidence of coronary artery bypass grafting/coronary angioplasty. Following 10 days of treatment (canrenoate group), only 9 patients presented with serum K and creatinine concentrations respectively > 5.5 mmol/l and > 2.0 mg/dl. Among those patients receiving canrenoate, the mitral E/A ratio was higher compared to the placebo group (p = 0.001) whereas the ESV was significantly reduced (p < 0.05). The deceleration time for reperfused patients receiving canrenoate was higher than that observed for reperfused patients in the placebo group. The intragroup EF was significantly increased (p = 0.042). Compared to the placebo group, the IVRT was significantly higher for unreperfused patients receiving canrenoate than in the placebo group (p = 0.001). Serum creatinine, blood urea and K levels as well as the incidence and extent of vessel disease were similar for both groups. No side effects were observed during the study period. CONCLUSIONS: Our data suggest that the combination of captopril plus canrenoate is feasible for the initial treatment of patients presenting with AMI. Besides, compared to captopril alone it is more efficacious in improving the E/A ratio, the ESV, the EF, and the IVRT.

Aged↗

A prospective study of anal sphincter injury due to childbirth.

BACKGROUND: Faecal incontinence commonly affects women, principally because of childbirth. Our aims were to determine the functional effect of childbirth on the pressures generated by the anal sphincter and to determine the patterns of injury to the sphincter. METHODS: Anal manometry was performed in 53 primiparous women prenatally, in 50 women at a median of 5 weeks postnatally, and repeated in 26 women at a median of 6 months postnatally. In addition, anal ultrasound was performed postnatally. Pelvic floor symptoms were assessed. The mode of delivery was examined to determine what variables affected anal function. RESULTS: Squeeze pressure was significantly reduced (P < 0.001) 6 weeks postnatally (mean, 170.4 cm H2O; standard deviation (s), 56) compared with the prenatal value (mean, 225.6 cm H2O; s, 58). This occurred in symptomatic and asymptomatic women and in women with a normal anal ultrasound. Resting pressure was significantly reduced at 6 weeks (P < 0.001; prenatal mean, 91.6 cm H2O; s, 25; postnatal mean, 80.Ocm H2O; s, 21). Delivery method (vaginal or caesarean) was the only factor significant for the reduced squeeze pressure (r=53.377; standard error, 13.973; P < 0.001). Sphincter defects (41%) were common but did not influence anal sphincter function. CONCLUSION: Anal function was significantly affected by vaginal delivery with short-duration follow-up. This occurred with and without evidence of an anal sphincter injury. The importance of a sphincter injury is questioned.

Adult↗

The Ceratitis capitata homologue of the Drosophila sex-determining gene sex-lethal is structurally conserved, but not sex-specifically regulated.

In Drosophila, Sxl functions as a binary switch in sex determination. Under the control of the primary sex-determining signal, it produces functional protein only in XX animals to implement female development. Here we report that, in contrast to Drosophila, the Sxl homologue in the Medfly, Ceratitis capitata, expresses the same mRNAs and protein isoforms in both XX and XY animals irrespective of the primary sex-determining signal. Also, experiments with two inducible transgenes demonstrate that the corresponding Ceratitis SXL product has no significant sex-transforming effects when expressed in Drosophila. Similar results have been obtained for the Sxl homologue of Musca domestica (Meise, M., Hilfiker-Kleiner, D., Brunner, C., DŁbendorfer, A., N¿thiger, R. and Bopp, D. (1998) Development 125, 1487-1494). Our findings suggest that Sxl acquired its master regulatory role in sex determination during evolution of the Acalyptratae group, most probably after phylogenetic divergence of the genus Drosophila from other genera of this group.

Amino Acid Sequence↗

The effect of a normal vaginal delivery on anal function.

BACKGROUND: To determine the effect of an uncomplicated vaginal delivery on anal sphincter function in primiparous women. METHODS: In a prospective study, anal manometry was performed prenatally and at 4-6 weeks postnatally in 18 primiparous women (11 undergoing vaginal delivery; seven having Cesarean section). No patient had any evidence of anal sphincter damage after delivery as determined by anal ultrasound and pudendal nerve terminal motor latency. RESULTS: Vaginal delivery was associated with a significant reduction in the squeeze pressure (SP: prenatal 269 cm H2O vs postnatal 204 cm H2O; p=0.004) but not the resting pressure (RP: prenatal 96 cm H2O vs postnatal 86 cm H2O; p=0.075). Cesarean section was not associated with any significant change in anal pressures. CONCLUSION: A normal vaginal delivery with no evidence of sphincter injury was associated with a significant effect on anal function when measured 4-6 weeks postnatally.

Adult↗

Division of the sphincter of Oddi for treatment of dysfunction associated with recurrent pancreatitis.

Increasing evidence suggests that motility disorders of the sphincter of Oddi may lead to episodes of recurrent pancreatitis in a small proportion of patients with the diagnosis of idiopathic recurrent pancreatitis. Over 10 years, 35 patients have been identified and treated for this condition. The aim of the study was to assess symptomatic outcome in these patients. Following the exclusion of common causes of pancreatitis the patients underwent sphincter of Oddi manometry. Patients with manometric abnormalities and three with normal manometric findings underwent treatment. Twenty-six patients with persistent symptoms underwent total division of the sphincter via open sphincteroplasty and septectomy. Patients were followed up according to symptoms and classed as having a cure, mild symptoms or no change. At a median follow-up of 24 (range 9-105) months, 15 of the 26 patients were cured, eight had only mild symptoms and three remained unchanged. In the majority of patients with a good clinical outcome, manometry had demonstrated sphincter of Oddi stenosis. Total division of the sphincter of Oddi is associated with good symptomatic outcome in patients with recurrent episodes of pancreatitis and documented sphincter of Oddi stenosis.

Adult↗

The white gene of Ceratitis capitata: a phenotypic marker for germline transformation.

Reliable germline transformation is required for molecular studies and ultimately for genetic control of economically important insects, such as the Mediterranean fruit fly (medfly) Ceratitis capitata. A prerequisite for the establishment and maintenance of transformant lines is selectable or phenotypically dominant markers. To this end, a complementary DNA clone derived from the medfly white gene was isolated, which showed substantial similarity to white genes in Drosophila melanogaster and other Diptera. It is correlated with a spontaneous mutation causing white eyes in the medfly and can be used to restore partial eye color in transgenic Drosophila carrying a null mutation in the endogenous white gene.

ATP-Binding Cassette Transporters↗

Opa-like repeats in the genome of the Medfly Ceratitis capitata.

The sequence determination of several genomic clones isolated from the Mediterranean fruitfly Ceratitis capitata identified the existence of opa-like repeats, often more than one being clustered in small chromosomal segments. These repeats have previously been shown to consist of stretches of tandemly reiterated glutamine-encoding residues, and they are found in multiple genes of several organisms. Most of the repeats described here are flanked or interrupted by stop codons in all reading frames and, thus, could not possibly be part of protein-coding sequences. Furthermore, these repeats, of which there are several hundred in the genome of the Medfly, can be used effectively for the determination of sequence polymorphisms, providing a convenient approach to obtain additional landmarks for the construction of genomic maps of this economically important insect.

Amino Acid Sequence↗