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F Fortunato

Publications and source records attributed to F Fortunato.

36 records · Page 2Linked to original sources
PubMed1998

Sarcoglycan deficiency in a large Italian population of myopathic patients.

Autosomal recessive limb-girdle muscular dystrophies are a heterogeneous group of genetic diseases with a wide spectrum of clinical severity and age of onset; mutations in the gene encoding the dystrophin-associated sarcoglycan proteins (alpha, beta, gamma and delta) have recently been shown to cause some cases of these myopathies (primary sarcoglycanopathies, types 2D, 2E, 2C and 2F, respectively). In this study we have examined a large population of Italian myopathic patients to determine the frequency of (alpha-, beta- and gamma-sarcoglycan deficiency and to correlate molecular defects with clinical phenotypes; to exclude the presence of primary dystrophinopathies both genetic and immunological analysis of dystrophin was performed. We report 12 patients (10 male and 2 female) with deficiency of either one or more sarcoglycan proteins. They were aged 8-56 years with onset between 4 and 30 years of age; they all presented with either mild, moderate or severe limb-girdle involvement associated with elevated blood creatine kinase levels and myopathic pattern at EMG; one was also affected with a mild dilation cardiomyopathy. All patients, except one, showed pathological muscle histological changes. Absence of all three proteins always correlates with severe forms, whereas mild protein deficiencies or isolated partial alpha-sarcoglycan deficiency correlate with either severe, moderate or mild forms.

Adolescent↗
PubMed1995

Utrophin expression during human fetal development.

Utrophin, a protein encoded by chromosome 6 is highly homologous to the cysteine-rich domain and most of the C-terminal domain of dystrophin. In order to clarify its functional role we analyzed its expression during human fetal development. We carried out immunohistochemical analysis on muscle from normal human fetuses at different ages of gestation using an antibody directed against a specific COOH-terminal sequence of the protein. In addition, we stained serial sections with antibodies against dystrophin and alpha-bungarotoxin FITC-BTX. Our findings show that, at week 9 of gestation, utrophin is diffusely expressed in the cytoplasm. From week 12 to 22 the immunostaining is still cytoplasmic, though the reaction intensity progressively decreases. Moreover we observed a strong reaction in fetal nerve at week 18 and 22. There was no correlation between utrophin expression and progressive dystrophin membrane localization.

Amino Acid Sequence↗
PubMed1995

Duplication of dystrophin gene and dissimilar clinical phenotype in the same family.

We report here three related patients with a duplication of exons 19-41 of the dystrophin gene, having dissimilar clinical phenotype and dystrophin immunohistochemistry. Two brothers aged six and three years had myalgia, proximal muscular weakness and hypertrophic calves, with 10- 20-fold increase of serum creatine kinase. Muscle biopsy showed dystrophic changes and reduced, patchy binding of dystrophin. The clinical and laboratory findings were consistent with a diagnosis of Becker muscular dystrophy with early onset. Their 14-year-old cousin had only mild hyperCKemia. His muscle biopsy was normal with only mild reduction of dystrophin immunostaining. At follow-up, he is still without symptoms and signs at age 19. All three patients had the same gene duplication and an increased dystrophin size of 507 kDa. Expression of the dystrophin-associated glycoproteins adhalin, alpha-dystroglycan, and beta-dystroglycan were normal in the three patients. An intrafamilial variability in patients carrying a partial duplication of the dystrophin gene may be related to a quantitative difference in mRNA.

Blotting, Southern↗
PubMed1994

Muscle phosphoglycerate mutase (PGAM) deficiency in the first Caucasian patient: biochemistry, muscle culture and 31P-MR spectroscopy.

Muscle phosphoglycerate mutase (PGAM) deficiency has been so far identified in only six patients, five of these being African Americans. We report the results of clinical, morphological, biochemical, muscle culture and 31P-MR spectroscopy studies in the first Caucasian patient with muscle PGAM deficiency. A 23-year-old man had a 10-year history of cramps after physical exertion with one episode of pigmenturia. Neurological examination and EMG study were normal. ECG and echocardiography revealed hypertrophy of the interventricular septum and slight dilation of the left chambers of the heart. Muscle biopsy revealed increased glycogen content and some accumulation of mitochondria. Muscle PGAM activity was markedly decreased (6.5% and 9.7% of control value in two different biopsies). Citrate synthase and other mitochondrial respiratory chain enzyme activities were much higher than normal. In contrast to the marked decrease of PGAM activity observed in muscle biopsy, total enzyme activity in the patient's aneural muscle culture was normal, being represented exclusively by BB isoenzyme. The deficiency of PGAM-MM isoenzyme was reproduced in the patient's innervated muscle culture. Muscle 31P-MR spectroscopy showed accumulation of phosphomonoesters only on fast "glycolytic" exercise. On "aerobic" exercise, Vmax, calculated from the work-energy cost transfer function, showed an increase consistent with the morphological and biochemical evidence of mitochondrial proliferation. This might represent a sort of compensatory aerobic effort in an attempt to restore muscle power.

Adult↗
PubMed1994

Chronic progressive external ophthalmoplegia: a correlative study of quantitative molecular data and histochemical and biochemical profile.

We studied muscle biopsies of 5 patients with Kearns-Sayre syndrome and 3 patients with chronic progressive external ophthalmoplegia all with the common deletion. Steady state levels of normal and deleted mitochondrial DNA (mtDNA) measured in each patient by quantitative PCR were correlated with histochemical and biochemical features. We found that (1) normal mtDNA levels were higher in many patients than in controls; (2) as levels of deleted mtDNA increased, so did levels of normal mtDNA; (3) cytochrome c oxidase (COX) activity and the percentage of COX negative fibers were both related to the levels of deleted mtDNA; and (4) as percentage of ragged red fibers increased, so did levels of total, deleted and normal mtDNA. The quantity of deleted mtDNA plays a key role in determining the severity of COX deficiency, which is responsible for the overaccumulation of mitochondria in muscle.

Adolescent↗
PubMed1993

Clinical and biochemical evidence of skeletal muscle involvement in galactose-1-phosphate uridyl transferase deficiency.

An 8-year-old boy with galactose-1-phosphate uridyl transferase (GALT) deficiency presented with hypotonia, muscle hypotrophy, hepatomegaly, bilateral cataract and mild mental retardation. Two brothers showed a GALT activity consistent with a homozygotic condition and both parents were found to be heterozygotes for this defect. Histological and ultrastructural examination of muscle biopsy specimens showed several necrotic fibres. GALT activity was undetectable in skeletal muscle and muscle tissue cultures; myotubes converted galactose to CO2 at a lower rate than controls. Galactose-1-phosphate was increased in the patient's red cells and muscle tissue. GALT deficiency, not previously described in muscle, may be of pathogenic relevance in determining the myopathic features present in GALT deficiency syndrome.

Biopsy↗
PubMed1993

Bezafibrate-induced myopathy: no evidence for defects in muscle metabolism.

A 58-year-old man with chronic renal failure developed severe muscle pain and tenderness 1 week after starting bezafibrate 400 mg daily. Serum creatine kinase was 32,280 U/l. Muscle biopsy revealed scattered necrotic fibers and mild type 2b atrophy. Muscle total and free carnitine were at the upper limits of the normal range. Biochemical investigations of muscle homogenate showed normal carnitine pelmityl transferase (CPT) as well as normal individual glycolytic and mitochondrial enzyme activities. Withdrawal of the drug was followed by rapid clinical improvement. Our study casts doubt on the hypothesis that bezafibrate is able to affect muscle metabolic pathways. It is likely that the drug acts on cholesterol constituents of the muscle membrane, producing discontinuities of the sarcolemma and initiating cell necrosis.

Bezafibrate↗
PubMed1992

Congenital myopathy associated with abnormal accumulation of desmin and dystrophin.

We studied a 5-yr-old boy clinically presenting congenital myopathy. Muscle biopsy showed sarcoplasmic accumulation of desmin filaments leading to diagnosis of desmin storage myopathy. An immunohistochemical study of other cytoskeletal proteins (actin, alpha-actinin, vimentin and dystrophin) was performed. Desmin positive areas reacted strongly with anti-mid-rod and C-terminus dystrophin antibodies. Probed with the same antibodies by Western blot, desmin and dystrophin showed normal molecular size but densitometric analysis demonstrated a parallel increase of both proteins. Our results indicate that intrasarcoplasmic desmin storage is associated with an abnormal accumulation of dystrophin. Since no other cytoskeletal proteins are accumulated this finding seems to be specific and suggests a possible structural and functional association between these two proteins in striated muscle.

Blotting, Western↗
PubMed1991

Glucose-6-phosphate dehydrogenase Lodi844C: a study on its expression in blood cells and muscle.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency was found in erythrocytes, lymphocytes and muscle of an Italian male, whose family has lived for at least three generations in Lodi (Lombardy, northern Italy). The subject was hospitalized for myalgia and dark urine after intense physical exercise, but no sign of anemia and chronic hemolysis were present at rest. Family studies revealed that the mother and the maternal aunt had the same enzymopathy. The enzyme-specific activity in red blood cells was 15% of control and the kinetic properties were the following: slower electrophoretic mobility; biphasic pH activity curve; slightly reduced thermal stability, and increased utilization of the substrate analogs. The analysis of our patient's DNA showed a G----C mutation at nucleotide 844 which causes an Asp----His amino acid change in position 282. This is the same mutation found by De Vita et al. in the G6PD Seattle-like variant. However, by following a new convention, we labelled our variant as G6PD Lodi844C. As far as the muscle is concerned, we found that the enzyme-specific activity in this tissue was 14% of control values, but cultured myotubes and myoblasts revealed a normal level of G6PD as well as skin fibroblasts. On the contrary in the same type of cultured cells obtained from G6PD Mediterranean subjects, the G6PD activity was about 20% of normal. Our results complete the characterization of this mutant enzyme, demonstrate the expression of the deficit in muscle and describe the enzyme behaviour in cultured cells.

Adult↗
PubMed1990

A case of mitochondrial myopathy, lactic acidosis and complex I deficiency.

A 34-year-old man affected by exercise intolerance, mild proximal weakness and severe lactic acidosis is described. Muscle biopsy revealed mitochondrial abnormalities and an increase of cytochrome c oxidase histochemical reaction. Biochemical investigations on isolated muscle mitochondria as well as polarographic studies revealed a mitochondrial NADH-CoQ reductase (complex I) deficiency. Mitochondrial dysfunction was confirmed by 31P nuclear magnetic resonance spectroscopy. Immunological investigation showed a generalized reduction of all complex I polypeptides. Genetic analysis did not reveal mitochondrial DNA deletions. The biochemical defect was not present in the patient's muscle tissue culture. Metabolic measurements and functional evaluation showed a reduced mechanical efficiency during exercise.

Acidosis, Lactic↗
PubMed1989

Muscle glucose-6-phosphate dehydrogenase deficiency.

Muscle glucose-6-phosphate dehydrogenase (G6PD) deficiency is described in four clinically heterogeneous patients: an athlete who developed myoglobinuria after physical exercise; a 7-year-old, mildly mentally retarded boy, who had episodes of dark urine and high creatine kinase; and two brothers of Sardinian origin, the elder showing moderate exercise intolerance. Histochemical and biochemical studies showed a lack of G6PD activity in muscle biopsy specimens as well as in erythrocytes. G6PD characterization in erythrocytes classified these mutant enzymes as Mediterranean variant in all the patients. The deficiency was confirmed in the patients' myotubes and skin fibroblasts, where residual activity was present. Electrophoretic studies in tissue culture extracts showed that the residual muscle enzyme migrated as a single electrophoretic band like normal human muscle G6PD.

Adolescent↗
PubMed1989

Cytochrome c oxidase during human fetal development.

Histochemical, biochemical and immunologic analysis of cytochrome c oxidase (COX) in skeletal muscle, heart and kidney during human fetal development was performed. COX histochemical activity was present only in few muscle fibres from the 11th to the 20th week of gestation. At the same developmental stage intrafusal muscle fibres, heart and kidney already showed strong activity. At the 28th week of gestation muscular COX activity was present in about 90% of the fibres. Tissue biochemical analysis confirmed these histochemical findings. Histochemical and biochemical findings compared to the immunocytochemical results and ELISA indicate that COX activity parallels the progressive synthesis of the enzyme in each tissue.

Electron Transport Complex IV↗
PubMed1987

Recessive carnitine palmityl transferase deficiency: biochemical studies in tissue cultures and platelets.

In a new case of carnitine palmityl transferase (CPT) deficiency the defect was documented in muscle and muscle cultures with an isotope exchange reaction, using different concentrations of palmityl-DL-carnitine and a forward reaction with and without albumin. The defect was expressed in cultured skin fibroblasts only by the "reverse" and "hydroxamate" reactions. The parents and the patient's daughter had intermediate levels of the enzyme in platelets and fibroblasts, supporting the concept that CPT deficiency has an autosomal recessive pattern of inheritance. The growth pattern and development of muscle cultures in this CPT-deficient patient indicate that CPT activity may be sufficient to allow normal muscle differentiation in culture without lipid storage.

Acyltransferases↗
PubMedDate not supplied

A sporadic, atypical case of desminopathy: morphological and immunological characterization.

Recently, abnormal expression of cyclin-dependent kinases was proposed as a possible cause of desminopathy. We describe an atypical case clinically characterized by severe respiratory distress. Muscle biopsy showed subsarcolemmal and intracytoplasmic accumulation areas, which intensively stained with anti-desmin antibodies and contained electrondense filamentous material at ultrastructural level. WB analysis showed 30% increased desmin signal compared to controls. Positive immunostain for CDC2 kinase, CDK2 and emerin and nuclear matrix-associated protein were, found in desmin-positive fibres.

Adult↗