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Biomedical subjects

F De Luca

Publications and source records attributed to F De Luca.

At least 109 records · Page 6Linked to original sources
PubMed1994

No changes of insulin sensitivity in cystic fibrosis patients with different degrees of glucose tolerance: an epidemiological and longitudinal study.

Plasma glucose and insulin responses to oral glucose and insulin sensitivity by the euglycemic hyperinsulinemic clamp technique were investigated in 30 cystic fibrosis patients with normal fasting blood glucose levels and normal (N = 12), impaired (N = 12) or diabetic (N = 6) glucose tolerance, and in 12 control subjects. In a subgroup of 10 cystic fibrosis patients with non-diabetic glucose tolerance both oral glucose tolerance test and clamp were performed again 48-52 months later. Following oral glucose, glycemic responses were higher in cystic fibrosis patients than in controls, whereas insulin responses were reduced significantly only in the patients with diabetic glucose tolerance. Insulin sensitivity did not differ significantly in the patient subgroups with different degrees of glucose tolerance and in controls. In the 10 patients who underwent a 4-year follow-up, insulin responses to oral glucose decreased significantly, whilst insulin sensitivity did not change substantially. Insulin sensitivity persisted unmodified even in the patients with deteriorating glucose tolerance. No correlation were observed between metabolic data and clinical status of patients. In conclusion, in cystic fibrosis subjects with fasting euglycemia and different degrees of glucose tolerance: (i) insulin sensitivity is not impaired; (ii) eventually changes of glucose tolerance over time are not associated with modifications of insulin sensitivity; (iii) insulin secretion deteriorates over time even in the patients with stable glucose tolerance; (iv) eventual deterioration of both glucose tolerance and insulin secretion is not linked to a worsening of either nutritional or clinical parameters.

Administration, Oral↗
PubMed1994

Immunohistochemical detection of p185 product, p21 product, and proliferating cell nuclear antigen (PCNA) in formalin-fixed, paraffin-embedded tissues from ovarian carcinomas. Preliminary data.

Immunohistochemical techniques for the detection of oncogene products and the assessment of cell kinetics can represent promising investigational tools in clinical oncology. In the present paper the immunohistochemical expression of p185, p21 and proliferating cell nuclear antigen (PCNA) was retrospectively assessed in formalin-fixed, paraffin-embedded tissue samples taken from 28 primary ovarian carcinomas at first surgery. Positive immunostaining for p185 was found in 0% of 6 Stage I and 23% of 22 Stage III-IV tumors. Positive immunostaining for p21 was observed in 0% of early and 41% of advanced carcinomas; this immunohistochemical finding correlated significantly with histologic grade (G3 vs G1-2 = 47% vs 9%, p = 0.042). Elevated PCNA immunoreactivity was detected in 33% of Stage I and 50% of Stage III-IV tumors. Among the 20 patients with advanced carcinoma who underwent cisplatin or carboplatin based chemotherapy followed by second-look laparotomy, the pathologic complete response (pCR) rate was 36% for patients with low PCNA expression and 0% for those with elevated PCNA expression. A tendency towards a higher pCR rate was also found for patients with negative immunostaining for p185 or for p21. The prognostic value of the immunohistochemical detection of p185, p21, and PCNA in ovarian carcinoma deserves to be further investigated.

Adenocarcinoma, Mucinous↗
PubMed1993

Fine-needle liver biopsy in patients with severely impaired coagulation.

Severe coagulation defects, as reflected by platelet count and prothrombin time, have always been considered a contraindication to needle biopsy of the liver, but there are very limited data on the actual rate of bleeding in patients with such severe alterations and none whatsoever on the bleeding risk associated with newer, fine-gauge needles that produce less trauma to the liver tissue. In addition, there has never been any evidence that platelet count and/or prothrombin time are the most sensitive indices of bleeding risk. This retrospective study of 85 patients, with platelet counts less than 50,000/mm3 and/or prothrombin times less than 50% of controls, subjected to ultrasound-guided fine-needle liver punctures for diagnostic or therapeutic (percutaneous ethanol injection) purposes showed no bleeding episodes after any of the 229 punctures performed. No type of replacement therapy was administered to correct clotting defects prior to the procedure. Correct pathologic diagnoses were obtained in 81.2% of all patients. Ultrasound-guided fine needle puncture appears to be safer than currently believed in patients with severe clotting defects and deserves further evaluation as an alternative to surgical procedures to diagnose and treat liver lesions, even when severe coagulation impairment is present.

Adult↗
PubMed1993

Longitudinal evaluation of glucose tolerance and insulin secretion in non-diabetic children and adolescents with cystic fibrosis: results of a two-year follow-up.

Thirty-two patients with cystic fibrosis and repeatedly normal fasting blood glucose underwent oral glucose tests and islet-cell antibody assessments on two occasions approximately two years apart. Fourteen patients underwent two iv glucose tolerance tests also. Although in the group as a whole mean glucose areas in response to the oral test remained substantially unmodified over the two-year period, the prevalence of glucose tolerance abnormalities increased from 37.5 to 50%. Insulin output in response to both oral and iv tolerance tests decreased over time. Worsening of insulin secretion and/or of glucose tolerance was never accompanied by deteriorating clinical status. Islet-cell antibodies were detected in no patients, even in those who developed a diabetic glucose tolerance. These results support, on a longitudinal basis, the view of a progressive impairment of B-cell function in cystic fibrosis, which may precede the onset of metabolic abnormalities and is not triggered by autoimmunity.

Adolescent↗
PubMed1993

Impaired response of free alpha-subunits after luteinizing hormone-releasing hormone and thyrotropin-releasing hormone stimulations in beta-thalassemia major.

In order to clarify whether the damage in gonadotropin secretion due to iron overload in patients with beta-thalassemia is of pituitary or hypothalamic origin, 14 euthyroid patients (8 females and 6 males, age 15-24 years) affected by beta-thalassemia major with hypogonadotropic hypogonadism were studied. Luteinizing-hormone (LH), follicle-stimulating hormone (FSH) and free alpha-subunit (FAS) were measured during LH-releasing hormone (LH-RH) stimulation test, and thyroid-stimulating hormone (TSH), prolactin (PRL) and FAS during thyrotropin-releasing hormone (TRH) stimulation test. During LH-RH stimulation, the mean basal LH, FSH and FAS levels were similar to those found in normal prepubertal children, but the peak values were lower than those found in such children. Also during TRH stimulation, the mean peak values of FAS were lower than those of normal prepubertal children, but the TSH response was normal. The lack of response of gonadotropins and FAS to LH-RH cannot exclude hypothalamic failure; however, the normal response of TSH to TRH, in spite of the poor response of FAS, indicates that the origin of hypogonadotropic hypogonadism is the pituitary damage concerning not only the gonadotroph but also the thyrotroph cells.

Adolescent↗
PubMed1993

[The psychopathological aspects of oral lichen planus (OLP)].

The etiopathology of oral lichen planus (OLP) is still uncertain. It is probably caused by a T lymphocytes cell-mediated autoimmune reaction. This reaction, caused by different pathogenic noxae, develops in subjects with a specific genetic pattern (HLA-DR on the keratinocytes) and some psychic attitude (higher Hamilton anxiety scale (HAS) and Hamilton depression scale (HDS) scores. In literature a psychic component has been often mentioned in OLP etiopathology. This work is a case-control study of replication: it aims to evaluate the importance of psychopathologic trait in patients affected by OLP. The study has been carried out on 16 patients (7 male and 9 female--average age 56) with OLP histologically confirmed. Before biopsy, they had been tested with: General health questionnaire (GHQ). Hamilton anxiety scale (HAS). Hamilton depression scale (HDS) with melancholia scale (MES). We have also studied a survey group of 14 patients affected by leukoplakia and neoplasms of the oral cavity (12 males and 2 female--average age 51). Before biopsy the survey group has been tested with the same questionnaire faced by the studied group. We chose the survey group as follows. Patients with leukoplakia show such similar lesions to OLP that the diagnosis is often histological; as far as patients with oral cavity tumours are concerned we hypothesized a more than usual anxious and depressed behaviour. We compared the score of the OLP patients to the one of the survey group patients using the "One-way Analysis of Variance" (ANOVA) method. The results confirmed that the patients with OLP showed very high scores in HAS and HDS, while the survey group scores were significantly lower.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1992

Alteration of the passive electrical properties of lymphocyte membranes induced by GM1 and GM3 glycolipids.

The electrical conductivity of normal human lymphocyte suspensions has been measured in the frequency range from 10 kHz to 100 MHz, where a well-pronounced conductivity dispersion occurs, caused by the surface polarization at the interface between the cell membrane and the extracellular solution. We have investigated the alteration of the passive electrical properties of the cytoplasmatic cell membrane induced by two different gangliosides (GM1 and GM3) inserted, at various concentrations, into the outer leaflet of membrane double layer. The alterations observed in the dielectric parameters (the membrane conductivity and the membrane permittivity) derived on the basis of a 'double-shell' model, result in an overall increase of the ion permeation across the membrane and an enhanced polarizability of its hydrophilic region for both gangliosides investigated. The relevance of these alterations is discussed.

Cell Membrane↗
PubMed1992

[Acute intestinal ischemia. Our experience].

Acute intestinal ischemia is a pathology which is relatively often encountered in elderly patients where the concomitance of other diseases make its prognosis more severe, especially since diagnosis is usually late. Laboratory tests and imaging techniques are not of great value to diagnosis since they do not provide pathognomonic data, but together with a careful anamnesis they contribute a series of findings which, taken as a whole, lead to the diagnosis of intestinal ischemia. The sole therapy is surgery--when still possible and the best results are obtained when surgery is performed at an early stage. The authors report a series of 12 cases of acute intestinal ischemia and underline the difficulty of diagnosing this subtle pathology and the advantages of aggressive surgical techniques.

Abdomen↗
PubMed1992

Spin-lattice relaxation in murine tumors after in vivo treatment with interferon alpha/beta or tumor necrosis factor alpha.

1H NMR spin-lattice relaxation times (T1) were measured in vitro and in vivo in Friend leukemia cell tumors during subcutaneous tumor growth in syngeneic mice and after in vivo administration of either purified murine interferon alpha/beta (IFN) or recombinant tumor necrosis factor alpha (TNF). Untreated tumors exhibited monoexponential T1 relaxation independently of tumor age at least until Day 16 after implantation. Histological examinations showed that under these conditions tumors were highly homogeneous and substantially free of necrotic areas. Peritumoral administrations of either IFN or TNF did not significantly alter the tumor relaxation properties at early stages of inhibition of tumor growth. The longitudinal relaxation decay became instead clearly biexponential at later stages (more than 7 days of IFN treatment or 2 days after TNF administration). While the T1 relaxation behavior could be unequivocally correlated with the presence of necrotic areas in these tumors, it could not be considered as an early marker of the altered growth capability, induced by administration of either IFN or TNF.

Animals↗
PubMed1992

Diagnostic value of growth hormone-releasing hormone test in children and adolescents with idiopathic growth hormone deficiency.

Average growth hormone (GH) peaks following an i.v. growth hormone releasing hormone (GHRH) 1-29 stimulation test were significantly lower in 48 children and adolescents with GH deficiency (GHD) than in 20 age-matched controls (15.2 + 12.7 vs 37.5 + 28.1 ng/ml, 2 P less than 0.001). Twelve patients exhibited a low GH peak (less than 5 ng/ml), 27 demonstrated a normal response (greater than 10 ng/ml) and 9 showed an intermediate rise in plasma GH (5-10 ng/ml). Six of the 12 patients with low GH response to the first GHRH stimulation failed to respond to two other tests immediately before and after a 1 week priming with s.c. GHRH. These subjects with subnormal GH increase at repeat testing had total GHD (TGHD) and multiple pituitary hormone deficiency (MPHD) and had suffered from perinatal distress. On the contrary, 26 of 27 patients with normal GH response to the first test had isolated GHD and only a minority (8/27) had signs of perinatal distress. It is concluded that perinatal injuries primarily damage pituitary structures and that a pituitary defect more probably underlies more severe forms (TGHD and MPHD) of GHD.

Adolescent↗
PubMed1992

Lee-Goldburg solid-state imaging.

A new approach to solid-state imaging (SSI) is presented. The method relies on narrowing the resonance line using the Lee-Goldburg sequence. The technique is easy to implement in practice and may find widespread applications in materials science.

Magnetic Resonance Spectroscopy↗
PubMed1992

Partial cerebral ischemia assessed by "in vivo" 31P NMR spectroscopy in rats.

31P NMR spectroscopy was used to assess the cerebral ischemia status in rats by measuring the relative levels of phosphate metabolites. Partial cerebral ischemia was induced in 49 rats by reversible occlusion of the carotid arteries. Rats were intubated and mechanically ventilated on a hypoxic gas mixture. Physiological parameters such as temperature and arterial pressure were strictly controlled during the experiments. 31P spectra were acquired at 7 T during basal observation, for 15-20 min after the induction of ischemia, and for 1 hr after reperfusion. Depletion and increase in PCr and Pi levels, respectively, were already observable in the collected spectra within few minutes after the onset of ischemia. No appreciable changes were found in the ATP levels.

Animals↗
PubMed1992

Immiscible fluids permeability by T1 imaging.

Soil pollution by hydrocarbon compounds is an important part of the more general pollution problem. Some analogies with research problems encountered in studies of oil reservoirs in rocks suggested to us the opportunity to study the pollution dynamics by imaging the spatial distribution of the pollutant in a wet soil model by an NMR imaging technique. Some preliminary results using T1-weighted imaging are reported here.

Magnetic Resonance Spectroscopy↗
PubMed1992

The effect of feeding on plasma immunoreactive ACTH and beta-endorphin levels in newborn infant.

In order to clarify whether an interaction between endogenous opioids and feeding occurs at birth, we studied Beta-endorphin (beta-EP) and ACTH plasma levels in response to a feed of 10% glucose, or formula, in 120 healthy full-term infants. Neither postprandial beta-EP nor ACTH increases were found at the 24th hour or on the fourth day of life. beta-EP physiology in newborn infants seems to be different from adults.

Adrenocorticotropic Hormone↗
PubMed1992

Comparison between serum CA 125 and CA 19-9 assays and tissular OC 125 and 1116NS 19-9 reactivity in malignant and benign ovarian tumors.

This preliminary study included 25 patients with primary epithelial ovarian cancer (EOC) (18 serous, 3 serous-mucinous, 1 endometrioid, 2 undifferentiated carcinomas and 1 malignant Brenner carcinoma); 2 patients with borderline ovarian tumors and 20 patients with benign ovarian tumors (9 benign cystic teratomas, 6 serous cystoadenomas and 5 mucinous cystoadenomas). Blood samples for the measurement of CA 125 and CA 19-9 were drawn from all patients before surgery. Serum CA 125 (Reference Value-RV = 65 U/ml) and CA 19-9 (RV = 40 U/ml) were measured with IRMAs using the monoclonal antibodies (MoAbs) OC 125 and 1116NS 19-9. The same antigens were detected on paraffin-embedded tissue sections by immunocytochemistry with the avidin-biotin complex method employing the same MoAbs used for serum IRMAs. Among the 25 patients with EOC serum CA 125 levels were elevated in 20: tissular OC 125 reactivity was observed in 15 (75%) of them. Of the 5 EOC patients with normal CA 125 levels, 4 showed OC 125 reactivity. Only 2 of the 25 EOC patients had elevated serum CA 19-9 levels: one of them had tissular 1116 NS 19-9 reactivity. Among the 23 patients with normal serum CA 19-9 levels only 5 had immunocytochemical reactivity for this antigen. The 2 patients with borderline ovarian tumors had negative serum CA 125 and CA 19-9 assay: tissular OC 125 reactivity was observed in both patients, while 1116 NS 19-9 reactivity was detected in only one.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMed1992

[Left ventricular false tendon: the most frequent cause of "innocent" murmur in childhood?].

BACKGROUND: The left ventricular false tendon (FT) is an anomalous fibrous or fibromuscular band stretching across the left ventricle. The false tendons extend from the septum to the left ventricular free wall or, more rarely, from the septum to a papillary muscle. The association between FT and innocent cardiac murmur has been pointed out. The aim of the present study was to assess the incidence of FTs in children with a murmur classified as innocent. METHODS: Two groups of subjects were selected. Group A consisted of 253 children with: 1) systolic ejection murmur; 2) normal electrocardiogram and 3) absence of clinical data suggesting cardiac disease. Group B consisted of 240 children clinically free of cardiac disease, and without any cardiac murmur. A FT was diagnosed by means of 2D echocardiogram whenever a linear band stretching across the left ventricular chamber was evident in at least two sections. RESULTS: One hundred and sixty-one children of group A (63.6%) reflected a left ventricular FT; only in 3 patients out of 161 the FT was associated with a small ventricular septal defect, whereas in 158 children the FT was the only abnormal finding. A normal echocardiogram was observed in 71 children (28.1%) of group A; whereas in 21 patients (8.3%) a congenital heart disease was diagnosed. In group B, only 33 subjects (13.8%) had a FT. The different incidence of FT in the two groups (63.6% versus 13.8%) was statistically significant (p less than 0.01). CONCLUSIONS: The study shows that about two thirds of children with innocent heart murmur reflect a left ventricular FT. Furthermore, FT is far more common in subjects with innocent cardiac murmur than in normal subjects. The relationship between FT and murmur thus appears very likely, although not definitely proven.

Adolescent↗