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L Tancredi

Publications and source records attributed to L Tancredi.

16 recordsLinked to original sources
PubMed2003

Clinical, morphological and immunological evaluation of six patients with dysferlin deficiency.

Limb girdle muscular dystrophy (LGMD) type 2B and distal Miyoshi myopathy (MM) are caused by mutations in a recently discovered mammalian gene coding for a skeletal muscle protein called dysferlin. The protein is normally expressed at the skeletal muscle level and absent or reduced in affected patients. We selected a clinically heterogeneous population of Italian myopathic patients with clinical evidence of myopathy and/or hyperCKemia, EMG myopathic pattern, and no alterations of the dystrophin-sarcoglycan complex. Calpain, merosin, emerin and caveolin were also tested and found normal in all patients. Dysferlin immunohistochemical and Western blot analyses allowed us to identify six patients with dysferlin deficiency: one with distal myopathy, four with limb girdle myopathy and one with hyperCKemia. No apoptosis was found in any of the six muscle specimens, although expression of the pro-apoptotic Fas antigen was mildly increased in two cases. Inflammatory reactions were present in two of the six cases, but we found no evidence of immune-mediated processes.

Adolescent↗
PubMed2002

Primary sclerosing cholangitis.

To discuss exhaustively: clinical, serological and pathologic aspects of primary sclerosing cholangitis (PSC); recent advantages in the knowledge of the disease's pathogenesis, therapeutic approaches that still appear today less preferable than liver transplantation. We have reviewed the most important researches on PSC of recent years. PSC is characterized by chronic inflammation of the main bile ducts, except for the gallbladder. HLA-B8 and HLA-DR3 haplotypes have been associated with PSC. It is probable that PSC is an organ-specific disease. Some studies have shown the presence of antibodies against the cytoplasm of neutrophils (ANCA) in the serum of more than 50% of patients, and the presence of anticatalase antibodies in 60% of patients. ANCAs induce leukocyte metabolic activation, that forms H2O2 and the anion superoxide O-2, which in turn impair components of both cell and cellular matrix. Catalase is mainly found in the liver; it is active in the "antioxidative defense system" against toxic O2 metabolites. Anticatalase antibodies are directed against an essential region of catalases, by inhibiting their enzymatic functions. In these conditions, a state of oxidative stress is determined by imbalanced ratio of oxidative to antioxidative factors, due to effective production of radical species as well as to simultaneous failure of antiradical defenses. Radical stress results in irreversible impairment of tissues. In PSC, primary lesions seem to be secondary to the production of radicals by ANCAs, deposited immunocomplex, complementary proteins and bacterial toxins. The subsequent lysis of bile epithelial cells seems to release catalases, that are thought to act as "nonself" once recognized by the immunocompetent system. Since the neoantigen catalase seems to be highly expressed in PSC patients, it may easily associate itself with MHC molecules for presentation to the immune system. Thus, in turn, B lymphocytes would be forced to produce anticatalase antibodies. Since anticatalase antibodies inhibit catalases, it can be hypothesized that they play a role in the pathogenesis of PSC. From a therapeutic viewpoint, the only effective cure is transplantation.

Cholangitis, Sclerosing↗
PubMed2001

Retrospective study of a large population of patients affected with mitochondrial disorders: clinical, morphological and molecular genetic evaluation.

Mitochondrial disorders are human genetic diseases with extremely variable clinical and genetic features. To better define them, we made a genotype-phenotype correlation in a series of 207 affected patients, and we examined most of them with six laboratory examinations (serum CK and basal lactate levels, EMG, cardiac and EEG studies, neuroradiology). We found that, depending on the genetic abnormality, hyperckemia occurs most often with either chronic progressive external ophthalmoplegia (CPEO) and ptosis or with limb weakness. Myopathic EMGs are more common than limb weakness, except in patients with A8344G mutations. Peripheral neuropathy, when present, is always axonal. About 80% of patients with A3243G and A8344G mutations have high basal lactate levels, whereas pure CPEO is never associated with increased lactate levels. Cardiac abnormalities mostly consist of conduction defects. Abnormalities on CT or MRI of the brain are relatively common in A3243G mutations independently of the clinical phenotype. Patients with multiple mtDNA deletions are somehow "protected" against the development of abnormalities with any of the tests. We conclude that, despite the phenotypic heterogeneity of mitochondrial disorders, correlation of clinical features and laboratory findings may give the clinician important clues to the genetic defect, allowing earlier diagnosis and counselling.

Adolescent↗
PubMed2001

Primary beta-sarcoglycanopathy manifesting as recurrent exercise-induced myoglobinuria.

We report an unusual presentation of a primary beta-sarcoglycanopathy (LGMD type 2E). A 12- year-old boy came to our attention after six episodes of exercise-induced myoglobinuria. Electromyogram showed mild myopathic features of the proximal lower limb muscles. Electrocardiogram was normal. Neurological examination revealed normal muscle strength and reduced deep tendon reflexes. A muscle biopsy showed rare regenerating fibers; the immunohistochemistry was normal for dystrophin, while all the sarcoglycans were diffusely decreased. Western blot analysis showed a relevant decrease of all sarcoglycan proteins and a mild dystrophin reduction. beta-Sarcoglycan gene analysis demonstrated a compound heterozygous status for these mutations: a novel A-T base pair substitution at nucleotide 85 in exon 2, changing the codon Arg to a stop codon; a C-T base pair substitution at nucleotide 272 in exon 3 changing a Arg to a Cys residue. We consider that exercise-induced myoglobinuria may be the presenting sign of primary beta-sarcoglycanopathy.

Base Sequence↗
PubMed2000

Severe polyneuropathy in a patient with Churg-Strauss syndrome.

We describe the clinicopathologic features of a 56-year-old woman affected with Churg-Strauss syndrome with major peripheral nerve involvement. The patient presented with a 1-month history of mainly distal upper-limb symmetrical paresthesias and hypostenia (bilateral "wrist drop"), palpable purpura and eosinophilia. Multiple pulmonary infiltrates and asthma had been present since the age of 52. Skin biopsy demonstrated an eosinophilic necrotizing vasculitis. During the hospitalization she was submitted to cardiac, bronchopulmonary, renal, and gastrointestinal evaluation and EMG. Peripheral nerve and skeletal muscle biopsies were performed. Sural nerve biopsy showed a marked degree of demyelination. A perivascular cellular infiltrate within the epineurium was immunoreactive for T lymphocytes and macrophages. Strong HLA-DR immunostaining was present in the endoneurium. IgM, IgE and fibrinogen deposition was found in some epi- and endoneurial vessels. Muscle biopsy showed neurogenic changes and 1 thrombosed vessel surrounded by mononuclear cells. Membrane attack complex (MAC) deposition was present in a few capillaries and major histocompatibility complex products I (MHCP I) was expressed at the subsarcolemmal level in a few isolated perivascular muscle fibers. After immunosuppressive therapy, the patient showed progressive improvement of both clinical symptoms and neurophysiological parameters.

Biopsy↗
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↗
PubMed1997

[Hepatitis C and systemic diseases].

In 1989 HCV was demonstrated to be the leading cause of non-A, non-B hepatitis. Not only HCV is able to determine chronic hepatitis in most patients, often leading to hepatocellular carcinoma, but it has also been shown to be strictly associated with a number of immunologically-mediated diseases. This review focuses on the reported associations between HCV and other diseases and the role that HCV might play in their pathogenesis.

Hepacivirus↗
PubMed1996

Brain glucose metabolism in chronic marijuana users at baseline and during marijuana intoxication.

Despite the widespread abuse of marijuana, knowledge about its effects in the human brain is limited. Brain glucose metabolism with and without delta 9 tetrahydrocannabinol (THC) (main psychoactive component of marijuana) was evaluated in eight normal subjects and eight chronic marijuana abusers with positron emission tomography. At baseline, marijuana abusers showed lower relative cerebellar metabolism than normal subjects. THC increased relative cerebellar metabolism in all subjects, but only abusers showed increases in orbitofrontal cortex, prefrontal cortex, and basal ganglia. Cerebellar metabolism during THC intoxication was significantly correlated with the subjective sense of intoxication. The decreased cerebellar metabolism in marijuana abusers at baseline could account for the motor deficits previously reported in these subjects. The activation of orbitofrontal cortex and basal ganglia by THC in the abusers but not in the normal subjects could underlie one of the mechanisms leading to the drive and the compulsion to self-administer the drug observed in addicted individuals.

Basal Ganglia↗
PubMed1992

Current and future applications of SPECT in clinical psychiatry.

Over the past 10 years several studies have been conducted in psychiatric and neurologic patients with single photon emission computed tomography (SPECT) to determine if patterns of brain dysfunction exist that characterize the different mental diseases. Although there has not been any finding that can be referred to as specific for a particular disease, SPECT studies have been able to demonstrate evidence of brain dysfunction in patients who, when tested with other means, showed no evidence of brain abnormalities. In this manuscript, the current and future applications of SPECT in the clinical practice of psychiatry are analyzed.

Brain↗
PubMed1991

Cerebellar metabolic activation by delta-9-tetrahydro-cannabinol in human brain: a study with positron emission tomography and 18F-2-fluoro-2-deoxyglucose.

We investigated the effects of acute i.v. administration of 2 mg of delta 9-tetrahydrocannabinol (THC) on regional brain glucose metabolism using 18F-2-fluoro-2-deoxyglucose and positron emission tomography (PET) in eight normal subjects. Subjects were tested twice: during baseline conditions and 30-40 min after THC administration. Changes in global cerebral glucose metabolism in response to THC were variable: three subjects showed an increase, three showed a decrease, and two showed no change. In contrast, all subjects showed an increase in normalized metabolism in the cerebellum following THC administration. Cerebellar changes were the only significant regional metabolic changes due to THC administration. The increase in metabolic activity in the cerebellum was correlated with the subjective sense of THC intoxication and with plasma THC concentration. Cerebellar localization of metabolic effects due to THC administration corresponds well with the high density of cannabinoid receptors known to be in this area.

Adult↗
PubMed1991

Classify and control: genetic information in the schools.

Recent advances in molecular and behavioral genetics are providing theoretical models to explain complex behavior--learning disabilities and behavioral problems--in simple biological terms. There are intrinsic difficulties in interpreting genetic information. Yet genetic explanations are particularly appealing in school systems pressed by demands for efficiency and accountability. Thus, genetic explanations are affecting the way children are categorized in the schools. This Article reviews genetic advances bearing on educational issues and their implementation through biological tests. It suggests the social consequences and legal implications of the growing prevalence of genetic assumptions.

Child↗
PubMed1987

Neural substrates of violent behaviour. A preliminary study with positron emission tomography.

Brain function was evaluated in four psychiatric patients with a history of repetitive purposeless violent behaviour, using EEG, CT scan, and positron emission tomography (PET). Three patients showed spiking activity in left temporal regions, and two showed CT scan abnormalities characterised by generalised cortical atrophy. The PET scans for the four cases showed evidence of blood flow and metabolic abnormalities in the left temporal lobe. Two patients also had derangement in the frontal cortex. The patients showing the largest defects with the PET scans were those whose CT scans were reported as normal. This paper shows the utility of PET in investigating possible brain derangements that could lead to violent behaviour.

Adult↗
PubMed1981

Medical and legal implications of side effects from neuroleptic drugs. A round-table discussion.

The side effects that may occur during treatment of schizophrenia with neuroleptic drugs are fully examined. Included are autonomic, extrapyramidal, other CNS, endocrine and metabolic, allergic, and skin and eye side effects. The differences between the side effect profiles of various antipsychotic drugs are noted. The restrictions imposed by laws designed to protect the patients's rights are evaluated with regard to the side effects of neuroleptic drugs. The meaning of informed consent is delineated.

Antipsychotic Agents↗
PubMedDate not supplied

[Alcoholic hepatopathy].

OBJECTIVES: To extensively discuss clinical features, laboratory data and pathology findings associated with alcoholic hepatitis as well as the new insights into pathogenesis and the appropriate therapy. DESIGN: Review of current literature. RESULTS: Acetaldehyde gives rise to neoantigens by complexing with various proteins, which, in turn, favors the appearance of autoantibodies. Antibodies against the hepatic lipoprotein and a number of hepatocyte surface glycoproteins have been detected in alcoholic hepatitis. Experimental studies have shown that acetaldehyde and malonyldialdehyde form highly immunogenic aggregates (MAA adducts). Antibody titers are usually higher in patients with more advanced disease, which argues for a major etiologic role. HLA antigens such as B8, DR3, DR4, which are usually associated with autoimmune diseases, are more frequently observed in alcoholic hepatitis patients. CONCLUSIONS: Despite the above, it is still questionable whether alcoholic hepatitis pathogenesis is autoimmune in origin. Why do only 15-20% of subjects who have long been abused alcohol develop hepatitis? What are the predisposing factors? What events trigger the immunologic reactivity? If MAA adducts play a role, why are not all the alcohol abusers affected by hepatitis? Transplantation outcome in well selected patients with alcoholic hepatitis is as good as--or even better than--the one reported for patients with different types of hepatitis.

Free Radicals↗