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S Grillo

Publications and source records attributed to S Grillo.

At least 19 recordsLinked to original sources
PubMed2000

Peroxovanadate induces tyrosine phosphorylation of phosphoinositide-dependent protein kinase-1 potential involvement of src kinase.

Phosphoinositide-dependent protein kinase-1 (PDK1) is a recently identified kinase that phosphorylates and activates protein kinase B (PKB). Activation of PKB by insulin is linked to its translocation from the cytosol to the plasma membrane. However, no data are available yet concerning the localization of PDK1 in insulin-sensitive tissue. Using isolated adipocytes, we studied the effect of insulin and of an insulin-mimicking agent peroxovanadate on the subcellular localization of PDK1. In unstimulated adipocytes, overexpressed PDK1 was mostly cytosolic with a low amount associated to membranes. Peroxovanadate stimulation induced the redistribution of PDK1 to the membranes while insulin was without effect. This peroxovanadate effect was dependent on phosphatidylinositol 3,4,5 triphosphate [PtdIns(3,4,5)P3] production as inhibition of PtdIns 3-kinase by wortmannin or deletion of the PH domain of PDK1 prevented the peroxovanadate-induced translocation of PDK1. Further, peroxovanadate-treatment induced a tyrosine phosphorylation of PDK1 which was wortmannin insensitive and did not require the PH domain of PDK1. An inhibitor of Src kinase (PP2) decreased the peroxovanadate-induced PDK1 tyrosine phosphorylation and overexpression of v-Src stimulated this phosphorylation. Mutation of tyrosine 373 of PDK1 abolished the v-Src induced PDK1 tyrosine phosphorylation and partially reduced the effect of peroxovanadate. Our findings suggest that PDK1 could be a substrate for tyrosine kinases and identify Src kinase as one of the tyrosine kinases able to phosphorylate PDK1.

3-Phosphoinositide-Dependent Protein Kinases↗
PubMed1999

Potential role of 3-phosphoinositide-dependent protein kinase 1 (PDK1) in insulin-stimulated glucose transporter 4 translocation in adipocytes.

Insulin stimulation of Glut 4 translocation requires the activation of phosphatidylinositol 3-kinase (PI 3-kinase) but the downstream pathway remains ill-defined. We demonstrated that the overexpression of PDK1 (3-phosphoinositide-dependent protein kinase 1), a downstream effector of PI 3-kinase, stimulated Glut 4 translocation in adipocytes. This effect does not require the PH domain of PDK1, but expression of the pleckstrin homology domain-deleted PDK1 inhibits the effect of insulin, but not okadaic acid, on Glut 4 translocation. These results support a role of the PDK1 pathway in the transmission of insulin signal to Glut translocation.

3-Phosphoinositide-Dependent Protein Kinases↗
PubMed1999

[Periconceptual folic acid intake by Sicilian couples at a risk of recurrence of NTD].

BACKGROUND AND AIM: The authors aimed to evaluate the frequency with which pregnant Sicilian women with a high risk of recurring neural tube defects (NTD) attending the Ultrasonography and Prenatal Diagnosis Clinic in the Department of Diagnosis and Treatment at Ospedale S. Bambino in Catania were aware of the preventive effect of folic acid supplements during the periconceptional period and whether they therefore took folic acid supplements before the next pregnancy. METHODS: All pregnant women undergoing ultrasonography between January 1997 and December 1998 were interviewed. It was noted whether any earlier offspring had suffered from NTD or whether relatives (sisters, brothers, parents) had also suffered from the same experience. They were also asked whether they knew about the preventive effect of periconceptional folic acid supplements on the development of NTD, whether their pregnancy was planned and whether they had taken periconceptional folic acid supplements and, if so, at what dose. RESULTS: Eighteen couples were identified as being at risk for recurring NTD, in 3 cases owing to an earlier pregnancy resulting in NTD (2 cases of spina bifida and 1 case of anencephaly) with a negative family history for NTD; a further 15 couples showed a positive family history for NTD. None of the women were aware of the preventive effect of acid folic supplements during the periconceptional period on the development of NTD. Out of 11 programmed pregnancies, none of the pregnant women took folic acid during the periconceptional phase. CONCLUSIONS: Pregnant Sicilian women at risk for recurring NTD interviewed by the authors were not aware of the possible prevention of NTD using folic acid supplements during the periconceptional phase.

Adult↗
PubMed1997

Potential role of protein kinase B in glucose transporter 4 translocation in adipocytes.

Phosphatidylinositol 3-kinase (PI 3-kinase) activation promotes glucose transporter 4 (Glut 4) translocation in adipocytes. In this study, we demonstrate that protein kinase B, a serine/threonine kinase stimulated by PI 3-kinase, is activated by both insulin and okadaic acid in isolated adipocytes, in parallel with their effects on Glut 4 translocation. In 3T3-L1 adipocytes, platelet-derived growth factor activated PI 3-kinase as efficiently as insulin but was only half as potent as insulin in promoting protein kinase B (PKB) activation. To look for a potential role of PKB in Glut 4 translocation, adipocytes were transfected with a constitutively active PKB (Gag-PKB) together with an epitope tagged transporter (Glut 4 myc). Gag-PKB was associated with all membrane fractions, whereas the endogenous PKB was mostly cytosolic. Expression of Gag-PKB led to an increase in Glut 4 myc amount at the cell surface. Our results suggest that PKB could play a role in promoting Glut 4 appearance at the cell surface following exposure of adipocytes to insulin and okadaic acid stimulation.

Adipocytes↗
PubMed1997

[Mediterranean anemia in 124 Sicilian pregnant women].

INTRODUCTION AND AIMS: The aim of this study was to verify knowledge of beta-thalassemia in a group of Sicilian puerpere. METHODS: The study was performed in a group of 124 pregnant women chosen at random from 2769 who gave birth in 1995 in the third trimester of pregnancy at the Specialised Maternity Hospital of Santo Bambino in Catania. RESULTS: A total of 124 puerpere replied to the questionnaire out of 124 interviewed. Their age ranged from 15 to 46 years old; the most frequent age group was 20-35 years old (81 cases-65.4%). 69.3% (86 cases) were married, 5.6% (7 cases) were separated or divorced, 24.9% (31 cases) were single or living with partners. The level of education was mainly lower (39.6%-49 cases) and upper (26.6%-33 cases) secondary school; there were few cases of illiteracy (3.2%-4 cases). The women were predominantly workers (25%-31 cases), employees (37.1%-41 cases) and in 14.4% (18 cases) neither of the couple worked. 4% (5 cases) of women lived alone. 73.3% (91 cases) reported that they knew what Mediterranean anemia was, 85% (35 cases) had recently spoken about this pathology with their doctor, 57.2% (71 cases) with their gynecologist. 36.2% (45 cases) knew the meaning of hemoglobinophoresis. 25% (31 cases) replied in the affirmative to the question regarding the hemoglobinophoresis test, 28.5% (35 cases) were unable to answer and 46.7% (58 cases) replied negatively. 11.2% (14 cases) of the puerperae had been informed about this disease when they were under 20, 39.5% (49 cases) between 20 and 35 years old, and 0.80% (1 case) after 36 years old. 36.2% of those interviewed (45 cases) responded correctly to the question "when does a carrier of Mediterranean anemia risk producing children suffering from a severe blood pathology?".

Adult↗
PubMed1996

Overexpression of a constitutively active form of phosphatidylinositol 3-kinase is sufficient to promote Glut 4 translocation in adipocytes.

Insulin stimulates glucose transport in its target cells by recruiting the glucose transporter Glut 4 from an intracellular compartment to the cell surface. Previous studies have indicated that phosphatidylinositol 3-kinase (PI 3-kinase) is a necessary step in this insulin action. We have investigated whether PI 3-kinase activation is sufficient to promote Glut 4 translocation in transiently transfected adipocytes. Rat adipose cells were cotransfected with expression vectors that allowed transient expression of epitope-tagged Glut 4 and a constitutively active form of PI 3-kinase (p110*). The expression of p110* induced the appearance of epitope-tagged Glut 4 at the cell surface at a level similar to that obtained after insulin treatment, whereas a kinase-dead version of p110* had no effect. The p110* effect was observed over a wide range of the transfected cDNA. When subcellular fractionation of adipocytes was performed, p110* was found, similar to the endogenous PI 3-kinase, enriched in the low density microsomal compartment, which also contains the Glut 4 vesicles. This could suggest that a specific localization of PI 3-kinase in this compartment is required for the action on Glut 4. The observations made with PI 3-kinase are in contrast with those seen with the MAP kinase cascade. Indeed, a constitutively active form of MAP kinase kinase had no effect on Glut 4 translocation in basal conditions. At the highest degree of expression, the constitutively active form of MAP kinase kinase slightly inhibited the insulin stimulation of Glut 4 translocation. Taken together, our results indicate that Glut 4 translocation can be efficiently promoted by an active form of PI 3-kinase but not by the activation of the MAP kinase pathway.

Adipocytes↗
PubMed1993

Chlamydia trachomatis diagnosis: a correlative study of pap smear and direct immunofluorescence.

From June 1989 to September 1990, 255 women with recurrent vaginitis, were evaluated, at the "Service of Precocious Diagnosis and Therapy of Gynecological Tumor" of the 1st Department of Obstetrics and Gynecology. They were compared with a control group of 255 women selected in the same time. All patients between the ages of 18-40 years, with normal sexual behaviour, had a negative colposcopy for HPV and HSV2 infections. The cervical smear with Papanicolaou technique and direct immunofluorescence (DIF) was performed in all patients. The specimens were examined with a fluorescence microscope (Leitz). Positive determinations were confined by examination a tha magnification of 600 X. Slides were scored as positive if at least 5 distinct apple-green fluorescence-stained elementary body per field was observed. The two groups were entirely comparable in age, parity, method of contraception, and number of sexual contacts over the preceding three months. Our data confirmed a higher incidence of Chlamydial infections in women with recurrent vaginitis (34.1%) than in control group (8.23%). In symptomatic women, more cases of metaplastic cells with cytoplasmic vacuolation, less inflammatory alteration and a lack of specific agents like CA and TV, were found than in the control group. The DIF positivity, in both groups, was connected with a cytological findings of metaplastic cells with cytoplasmic vacuolation in 72.3% and 50% respectively.

Adult↗
PubMed1982

[Vascular changes in postmastectomy "thick arm"].

The authors, after shortly outlining some pathogenetic theories about postmastectomy "big arm", especially dwell upon the theory of the hindered venous discharge. They, subsequently, through a clear and interesting phlebographic iconography, illustrate ten of the 41 cases suffering from such syndrome, they recently had the opportunity to observe. On the basis of their own experience, and according to part of the literature thereabout, the authors think very probably the postmastectomy "big arm" is to be ascribed to the hindered venous reflux of upper limb (for thrombosis or compression), due to the operation of mastectomy. As a conclusion, they suggest the improvement or recovery of this syndrome by stepping over the stenosed venous tract through a by-pass.

Arm↗
PubMed1979

[Postoperative hypergastrinemia].

After reviewing the more recent acquisitions on the physiology and pathophysiology of gastrin, the authors concentrate on situations of hypergastrinemia, which they divide into a hyperhydrochloric and a hypohydrochloric variety. Among the former, which they subdivide into preoperative and postoperative, the authors discuss problems of differential diagnosis versus peptic ulcers in patients so afflicted. To that end they propose diagnostic policies comprising among other instrumental and laboratory tests the study of gastric secretion, blood gastrin levels in basal conditions and after stimulation by a protein meal, BBS, secretin, and calcium. From analysis of the results of such tests they were able to find a precise nosographic placement for postoperative hypergastrinemia, and from there they arrived at surgical programs aiming to correct postoperative peptic ulcers on the basis of their etiology and pathogenesis.

Gastrectomy↗
PubMed1979

[Primary closure of the perineum after Miles's abdominoperineal amputation for carcinoma of the rectum (author's transl)].

In view of the results obtained in 32 cases of primary closure of the perineum after amputation of the rectum for cancer, the authors believe that this policy is best after removal of the malignancy by the abdominoperineal approach. Unquestionable advantages are shortening of the patient's hospital stay and a more rapid recovery; the possible disadvantages are relatively rare, from an uncommonly severe dysmetabolic situation to local disorders such as poor hemostasis, contamination of the operation site, inadequate preoperative antibacterial protection, or an unusually large tumor.

Abdomen↗
PubMed1979

[Coloportal fistula in ulcerative colitis (massive penetration, through the splenic vein, of barium and air into the portal system during barium enema)].

The authors describe one case of massive penetration of barium and air through the splenic vein into the portal system during administration of a radiopaque enema to a woman suffering from hemorrhagic proctitis in the florid phase. They provide a detailed description of this rare clinical case and discuss the possible etiology and pathophysiology of the observed event.

Barium Sulfate↗
PubMed1978

Inotropic effects of calcitonin in man.

The Authors have studied th haemodynamic response of ten normal subjects to the intravenous administration of 160 MRC.U. of Calcitonin in 60 min, by serial measurement of the systolic time intervals. The analysis of results pointed out a minor inotropic effect starting from the 10th minute from the beginning of the infusion. Little but significant decrements (P less than 0.01) in the duration of the pre-ejection phase of the isovolumetric contraction time, as well as a significant increase (P less than 0.01) in the LVET/PEP ratio, have been noted. A negative chronotropic effect (P less than 0.05) has been noted starting from the 30th minute. The mechanism by which Calcitonin can modify the myocardial inotropism in the normal subject is till now unknown, and it could be related to the interference of this hormore on the endocellular movements of Calcium, and on the cellular levels of cyclic AMP.

Adult↗
PubMed1978

[Preventive intervention during the planning of a new factory: contribution of an occupational medicine service on installation of a ceramic dye-producing plant].

The control during the planning of a factory is a sort of prevention. For instance, we suggested industrial hygiene standards for a new chemical plant, which have been into account. According to our suggestions they set up a closed factory process, a dust and fumes filtering plant and the water recycle. After some controls outside the factory, lead and dust concentrations were below the maximum allowed levels (30 and 5 mg/Nmc).

Air Pollutants↗
PubMedDate not supplied

From insulin receptor signalling to Glut 4 translocation abnormalities in obesity and insulin resistance.

Insulin resistance is commonly associated with obesity in rodents. Using mice made obese with goldthioglucose (GTG-obese mice), we have shown that insulin resistance results from defects at the level of the receptor and from intracellular alterations in insulin signalling pathway, without major alteration in the number of the Glut 4 glucose transporter. Activation of phosphatidylinositol 3-kinase (PI 3-kinase) was found to be profoundly affected in response to insulin. This defect appears very early in the development of obesity, together with a marked decrease in IRS 1 tyrosine phosphorylation. In order to better understand the abnormalities in glucose transport in insulin resistance, we have studied the pathway leading from the insulin receptor kinase stimulation to the translocation of the Glut 4 containing vesicles. This stimulation involves the activation of PI 3-kinase, which in turns activates protein kinase B. We have then focussed at the mechanism of vesicle exocytosis, and more specifically at the role of the small GTPase Rab4 in this process. We have shown that Rab4 participates, first in the intracellular retention of the Glut 4 containing vesicles, second in the insulin signalling pathway leading to glucose transporter translocation.

Adipose Tissue↗