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G Gallo

Publications and source records attributed to G Gallo.

At least 91 records · Page 5Linked to original sources
PubMed1997

Tri-iodothyronine increases insulin-like growth factor binding protein-4 expression in rat hepatocytes.

Previous in vivo studies demonstrated significant variations in insulin-like growth factor binding protein-1 (IGFBP-1), IGFBP-2 and IGFBP-4 hepatic mRNAs and/or serum levels depending on the rat thyroid status. In this study we employed cultured hepatocytes from adult rats to demonstrate a possible direct regulation of these genes by tri-iodothyronine (T3). Northern blot analysis revealed that IGFBP-1 and -4 messages were clearly expressed, whereas IGFBP-2 signal was barely detectable. No significant effects on IGFBP-1 mRNA level or on peptide secretion were detected in T3-cultured hepatocytes. In contrast, significant increases in IGFBP-4 mRNA steady-state levels as well as in IGFBP-4 secretion were observed in hepatocytes cultured for 12-24 h in the presence of T3. The T3 effect on IGFBP-4 transcript levels appears to consist of enhanced gene transcription and is independent of ongoing protein synthesis. The T3-increased IGFBP-4 expression in cultured hepatocytes is consistent with our in vivo experiments demonstrating an increase in hepatic IGFBP-4 mRNA and serum IGFBP-4 levels in T3-treated rats. Furthermore, significant decreases in hepatic IGFBP-4 message and serum IGFBP-4 levels were observed in hypothyroid rats compared with euthyroid controls. Our data establish an important direct role for thyroid hormone in regulating IGFBP-4 expression and consequently IGF activity.

Animals↗
PubMed1997

Case fatality rate of acute hepatitis in Italy: results from a 10 year surveillance.

Using data from the surveillance system for acute viral hepatitis we have evaluated the case fatality rate of viral hepatitis in Italy. 71 deaths (0.3%) occurred among the 21,553 reported acute viral hepatitis cases from 1985-1994. None reported history of exposure to drugs or toxins. The highest case fatality rate was observed for B and NANB hepatitis (0.5%). One death occurred among the 6,353 (0.02%) hepatitis A cases and 1 among the 909 (0.1%) anti-HCV positive NANB hepatitis cases. The case fatality for Delta hepatitis was 0.2% (1/422). Case fatality rate was similar in both sexes; increasing with age; 0.03% were < 15 years of age, 0.1%, 15-24 year-old, and 0.5%, > or = 25 years. Subjects older than 24 years of age accounted for 81.4% of total deaths. Intravenous drug use, blood transfusion and other parenteral exposures were the three most frequent non-mutually exclusive sources of infection reported by subjects who died from B and NANB hepatitis. These findings indicate that the survival rate of acute B and NANB hepatitis is lower than that of acute hepatitis A; moreover in Italy, as in other Western countries, acute HCV seems to cause liver failure only rarely.

Adolescent↗
PubMed1997

Presenilin-1 is associated with Alzheimer's disease amyloid.

Mutations in presenilin (PS)-1 and -2, located on chromosome 14 and 1 respectively, are the major association with early-onset familial Alzheimer's disease (FAD). FAD has also been linked to mutations in the amyloid beta precursor protein (beta PP), and the presence of the apolipoprotein E4 allele is a risk factor for late-onset AD. The role of PS in FAD and in sporadic AD is unclear. We previously reported the presence of a PS-1 carboxyl-terminal epitope in neuritic plaques (Wisniewski T, Palha JA, Ghiso J, Frangione B: S182 protein in Alzheimer's disease neuritic plaques. Lancet 1995, 346:1366). In the present study, we examined a number of biochemically different cerebral and systemic amyloidoses, finding the PS-1 carboxy epitope only in association with amyloid beta (A beta) lesions. We confirm the presence of this epitope ultrastructurally in neuritic plaques. In addition, biochemical and amino acid sequence data are presented for an association of the 18-kd carboxy fragment of PS-1 with neuritic plaques with a start at residue 300. Three of the proteins with linkage to AD have now been found as components of neuritic plaques. It remains to be determined whether all of these proteins are involved in the same or different pathological pathway(s) and which of these proteins is the most important for the common, late-onset form of AD.

Adult↗
PubMed1997

Nodular pulmonary immunoglobulin light chain deposits with coexistent amyloid and nonamyloid features in an HIV-infected patient.

Isolated nodular pulmonary amyloidosis is a rare condition characterized by localized deposits of immunoglobulin (Ig) light chain amyloid. Nonamyloid nodular light chain deposits in lungs can occur in systemic light chain deposition disease. Both amyloid and nonamyloid light chain deposits have been described at separate sites in the same or different organs but rarely in lungs. We report the clinical, radiologic, and pathologic findings in a drug user infected with the human immunodeficiency virus who had multinodular pulmonary Ig light chain deposits consisting of both amyloid and nonamyloid granular morphologic features. The deposits, closely associated with numerous plasma cells, had a unique histochemical and ultrastructural profile, with intermixed Congo red-positive fibrillar amyloid and Congo red-negative granular nonamyloid components. Immunohistochemical and immunoelectron microscopic studies showed reactivity of both the fibrillar and granular deposits for kappa and lambda light chains but not heavy chains. There was no evidence of restricted clonality of local or bone marrow plasma cells, serum or urine monoclonal protein, or secondary causes of amyloidosis. The amyloid deposits (but not the nonamyloid deposits) were reactive with antibody to amyloid rho component. There was no staining for other types of amyloid, i.e., amyloid A or transthyretin. The relationship between pulmonary amyloidosis, infection with the human immunodeficiency virus, and illicit drug use is unknown. We conclude that the nodular pulmonary light chain deposits with both amyloid and nonamyloid morphologic features are related to local plasma cell proliferation and that the fibrillar and nonfibrillar components most likely result from different conformations of the Ig light chains.

Adult↗
PubMed1996

Development of focal segmental sclerosis and hyalinosis in hemolytic uremic syndrome.

Renal biopsies from 19 boys and 11 girls, most with moderate or severe forms of hemolytic uremic syndrome (HUS) of the classic diarrhea-associated type, were analyzed as part of their long-term follow-up. Patients were biopsied because of late or persistent proteinuria, hypertension, and prolonged renal failure. The median length of follow-up was 11.2 years (range 0.9-22.0 years). Four histological groups were identified: focal segmental glomerulosclerosis and hyalinosis (FSGSH) (17 patients), diffuse mesangial proliferative glomerulonephritis (DMPGN) (9 patients), diffuse glomerulosclerosis (2 patients), and minimal glomerular changes (2 patients). The median interval between the onset of disease and renal biopsy was significantly shorter in DMPGN than in FSGSH (P < 0.001). The pathological findings may be the expression of two different stages of the same dynamic process: a regular sequence of glomerular lesions consisting of early DMPGN, followed by FSGSH. This lesion would ultimately lead to the final stage of global glomerulosclerosis. At the last examination, only a quarter of the patients had normal renal function. These observations also confirm that prolonged oligoanuria during the acute stage of HUS frequently results in an unfavorable long-term prognosis.

Child↗
PubMed1996

Fibrillary glomerulonephritis related to serum fibrillar immunoglobulin-fibronectin complexes.

Fibrillary glomerulonephritis is a disease of uncertain origin and pathogenesis characterized by nonamyloidotic fibrils in glomeruli. We report immunohistological, immunochemical, and biochemical studies of a serum fibrillar cryoprecipitate obtained from a patient with fibrillary glomerulonephritis, that formed on prolonged storage at 4 degrees C. By Western blot and amino acid sequence analysis, the cryoprecipitated fibril components consisted of immunoglobulins, heavy chains gamma and mu, light chains kappa and lambda, and fibronectin, similar to the proteins identified by immunofluorescence and immunoelectron microscopy in the glomerular fibrils. These findings support the hypothesis that serum precursors may be the source of the fibrillar deposits and suggest a role for immunoglobulin-fibronectin complexes in the pathogenesis of fibrillary glomerulonephritis.

Antigen-Antibody Complex↗
PubMed1996

Muscle reinnervation in hypothyroid rats.

Reinnervation of extensor digitorum longus muscle following crush of sciatic nerve was studied in rats made hypothyroid after weaning. In vitro intracellular recordings of muscle cell postsynaptic potentials were carried out; moreover twitch and tetanus following direct muscle stimulation and nerve stimulation were recorded. Frequency of miniature end-plate potentials (mepps) may be regarded as an index of presynaptic mechanism in regenerated nerve endings: when regenerating axons reach the muscle, the frequency of spontaneous acetylcholine quantal release is very low and increases in subsequent weeks. No significant differences were noted in miniature end-plate potential frequency between muscles of normal and hypothyroid rats at the same time from denervation; mepp amplitude was higher in hypothyroids, in accordance with the smaller muscle fibre diameters. Regenerating nerve fibres entering the muscle extensively sprout, giving rise to a number of nerve endings which exceeding the number of muscle cells, are subsequently withdrawn; correspondingly, muscle cells are transiently polyinnervated and the number of polyinnervated muscle cells peaks decreases subsequently approximating zero. The percentage of polyinnervated cells peaked sooner in hypothyroid rats than in controls and afterwards decreased; a tail of polyinnervation was found at long term. Tension recording experiments showed a shorter time of reinnervation of muscles in hypothyroid rats, but no difference in regeneration rate could be argued. These findings suggest an influence of thyroid hormones in the stabilization of motor innervation of reinnervated muscle, but not in nerve regeneration process.

Animals↗
PubMed1996

Light chain cardiomyopathy. Structural analysis of the light chain tissue deposits.

Cardiomyopathy due to monoclonal light chain deposits is a complication of plasma cell disorders. The deposits may be either fibrillar as in light chain amyloid or nonfibrillar as in light chain deposition disease. The reasons for these structural differences are still unknown. We characterized the myocardial deposits by immunohistochemical examination of sections and extraction and biochemical analysis of the tissue deposits in a patient (MCM) who died of myeloma and systemic light chain deposition disease. Amino acid sequence analysis of the extracted nonfibrillar MCM kappa-light chain reveals that it belongs to the L12a germline subset of the kappa(I) protein and contains five distinctive amino acid substitutions (three in the framework region III and two in the complementarity-determining region III) that have not been reported previously in the same positions in other kappa(I) light chains. The theoretically determined isoelectric point (pI 8.21) of the MCM light chain is high compared with the low isoelectric point of other Bence Jones proteins from subjects without light chain deposition disease. The diffuse binding to basement membranes and the high isoelectric point of the MCM kappa-light chain suggest electrostatic interaction as a possible mechanism of tissue deposition. The spatial locations of the five distinctive residues and a sixth rare substitution of the MCM protein modeled on the backbone structure of REI, a kappa(I)-soluble Bence Jones light chain of known three-dimensional structure, may be responsible for protein destabilization, partial unfolding, and aggregation leading to tissue deposition.

Adult↗
PubMed1996

[Heart arrest during dipyridamole scintigraphy: report of 3 cases].

Potentially life threatening rythm disturbances, such as third degree A-V block and sinus arrest without "escape rythm", represent infrequent and unexpected events during dipyridamole thallium scintigraphy. We report three cases of cardiac arrest requiring resuscitation maneuvers after dipyridamole infusion during myocardial thallium scan. On the basis of these clinical observations we suggest that a trained cardiologist and resuscitation kit should be available in nuclear lab. Moreover elderly patients may require careful screening for preexisting conduction defects and sick sinus syndrome. When dipyridamole infusion provokes severe bradyarrhythmias not related to myocardial ischemia, a transesophageal electrophysiological study should always be performed.

Aged↗
PubMed1995

Cyclic remodelling of growth cone lamellae and the effect of target tissue.

We report the existence of cyclical fluctuations in the total size of growth cone lamellae, represented by membrane protrusions and retractions, and show that aspects of this behavior can be regulated by the target tissue for the nerve fibers. The transition of the growth cone from a high to a less motile state, which occurs in the presence of the target tissue, has implications for the mechanisms that underlie nerve fiber elongation during development.

Animals↗
PubMed1995

Molecular similarity matrices and quantitative structure-activity relationships: a case study with methodological implications.

Recently, statistical analysis of molecular similarity matrices has been applied to the quantitative structure-activity relationship (QSAR) analysis of a number of molecular series. This paper addresses a number of methodological issues relative to the similarity matrices. A series of halogenated aliphatic hydrocarbons, for which the mutation (aneuploidy) induction ability had previously been determined, was used as test bench. The chemical information carried by the similarity matrices was shown to overlap to a considerable extent the information carried by the classical descriptors (physical chemical and quantum mechanical parameters). A good QSAR was obtained on the basis of the similarity matrices, in analogy with that obtained with the classical descriptors; however, the similarity matrices neither complemented the classical descriptors nor were able to improve on their performance. The effect of the compound's spatial orientation on the similarity values was also investigated.

Aneuploidy↗
PubMed1995

Dysembryoplastic neuroepithelial tumor: morphological, immunocytochemical, and deoxyribonucleic acid analyses in a pediatric series.

Overtreatment by radiotherapy and/or chemotherapy for central nervous system tumors in infancy and childhood may be deleterious, so the recognition of surgically curable clinicopathological entities is mandatory. The dysembryoplastic neuroepithelial tumor is a complex multinodular lesion consisting of glial nodules, associated with a specific glioneuronal element and/or with focal cortical dysplasia, and occurring in young patients presenting with intractable, mostly complex partial, seizures without neurological deterioration. We report on 14 patients; 9 were from a series of 600 pediatric patients with intracranial central nervous system tumors studied at a single institution from 1988 to 1993, and 5 were referred from other pediatric hospitals. Six tumors were frontal, six were temporal, one was parietal, and one was occipitoparietal. Computed tomographic scans disclosed hypodense lesions with cystic appearances in 4 patients and slight focal postcontrast enhancements in only 2 patients, whereas magnetic resonance imaging, available for 7 of 14 patients, showed hypointense lesions in T1-weighted images and hyperintense lesions in T2-weighted images. Deformities of the overlying cranium were also observed in five patients. The age range at the time of surgery (excluding a 20-year-old male patient who underwent surgery at the main pediatric hospital) was 2.6 to 13 years, with a mean of 6.68 years. The male to female patient ratio was 10:4, and the duration of symptoms was 0.2 to 6 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Prenatal evaluation of congenital heart disease in high-risk pregnancies.

The authors report their experience of echocardiography performed on a group of 736 pregnancies with specific risk-factors for congenital heart disease (CHD). The aim of the study was to evaluate the influence of specific risk-factors (established through the genetic counselling) in detecting fetal cardiac anomalies and diagnostic accuracy of extended fetal echocardiographic examination in high-risk pregnancies. Twenty-seven heart defects were observed (3.6%), of these 24 were detected at ultrasound. Specificity and sensitivity were 99% and 90% respectively. These results suggest the importance of an early detection of pregnancies at increased risk for CHD and confirm the good diagnostic accuracy of a multiple cardiac examination.

Animals↗
PubMed1995

Pregnancy in adolescents. A case-control study.

OBJECTIVE: to investigate pregnancy outcome and incidence of pregnancy-related disorders in the adolescent. DESIGN: a matched control retrospective study. SUBJECTS: pregnant adolescents aged 14 to 19 years admitted to the Departments of Obstetrics and Gynecology--Policlinico Umberto I, between the years 1984 and 1993; a comparable number of pregnancies aged 20 to 24 years was considered as a control group. RESULTS: In the 10 yrs. period a total of 304 pregnancies in adolescents were considered. Preterm deliveries were 9.5% in the adolescent group vs 5.9% in control (P > 0.05). A higher incidence was found in number of cesarean section (P < 0.001), spontaneous abortion (P = 0.003), intrauterine growth retardation (P = 0.04) and fetal distress (P = 0.04) in the adolescent group vs matched controls. Also mean birth weight was significantly lower in the adolescent group when compared with normal group (P < 0.001). CONCLUSION: we found a higher incidence of obstetric complications, such as IUGR, acute fetal distress in labor and lower birth weight, in the adolescent group, resulting in a higher number of cesarean sections. We hypothesise that the relative state of "hypoarterialisation" characteristic of the adolescent uterus may be involved in the afore-mentioned complications.

Adolescent↗
PubMed1995

Clinical and ultrasonographic implications of uterine leiomyomatosis in pregnancy.

OBJECTIVE: To study the complications related to leiomyomatosis in pregnancy by clinical and ultrasonographic assessment. DESIGN: A retrospective study. SUBJECTS: All pregnancies admitted to the 2nd Institute of Gynecology and Obstetrics, Policlinico Umberto I, in the period between January 1992 to December 1993 were surveyed. RESULTS: Gestational age at the time of ultrasonographic neoplasm diagnosis was 25.1 +/- 13.4 weeks, 'we found no correlation between maternal age or parity affecting pregnancy outcome, Leiomyomatosis complicated pregnancy rate was 1.68%. Myomatosis was diagnosed clinically in 25 of 67 cases (37.3%). Regarding the location of the neoplasm, 59% was located in the corpus-uteri, 21% was considered a diffuse neoplasm and the 14% was located in the fundus. Threatened abortion was the most frequent complication (20%), abortion was the second (16.4%). We observed an increased abortion threat rate (p < 0.001) in those cases where the leiomyoma was in relation with the placenta. We had a surgery rate of 76% in pregnancies complicated by myomatosis, and the indication for surgery was given either primarily or exclusively by the presence of myomatous formation in 19 cases (50%). CONCLUSIONS: Our study suggests that location of the leiomyoma in relation to the placenta is a higher risk factor than its size, and that there is a higher risk for threats of abortion and abortion rates in pregnancies complicated by leiomyomatosis. We recommend that every pregnant woman with a suspected myoma should be ultrasonographically scanned.

Adult↗
PubMed1994

Response of fast muscle innervation to hypothyroidism.

The early period of motor innervation development is characterized by multiple innervation of muscle cells. This transitory state in rat extensor digitorum longus (edl) muscle is normally concluded at weaning when a 1:1 ratio between nerve endings and muscle cells is reached. Motor innervation of edl muscle in rats made hypothyroid after weaning was studied in three ways: electrophysiology (intracellular recordings of muscle postsynaptic potentials) was carried out to study neuromuscular transmission; silver impregnation of terminal axons to observe sprouting; force production in twitch and tetanus following direct muscle stimulation and nerve stimulation. A number of multiply innervated muscle cells was found in hypothyroid rats following two months of treatment. This finding seems to be related to the appearance of nodal sprouting in motor axons. No sign of denervated end-plates was found. Twitch and tetanus tension were smaller than in controls, but they were bigger when referred to unitary muscle mass. Time course of twitch, particularly half relaxation, was slowed in muscles of hypothyroid rats. These findings suggest that plastic processes occur in muscle innervation of rats made hypothyroid after weaning. Therefore, thyroid hormones play a role in stabilizing motor innervation not only during development, but also in adults.

Animals↗