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Featured researches published by R. Zanchetta.


Journal of Hepatology | 1998

Insulin-dependent diabetes mellitus during alpha-interferon therapy for chronic viral hepatitis

Paolo Fabris; Corrado Betterle; Nella Greggio; R. Zanchetta; Emanuele Bosi; Maria Raffaella Biasin; Fausto de Lalla

A 29-year-old man was observed to develop insulin-dependent diabetes mellitus following a 5-month treatment with recombinant alpha-2b-interferon for chronic hepatitis C. After the onset of the disease, serum samples that had, respectively, been collected before therapy commencement, at month 3, and at the onset of insulin-dependent diabetes mellitus were tested for islet-cell (ICA-IgG), glutamic acid decarboxylase (GAD-Abs), IA2 (IA2-Abs) and insulin (IA-Abs) autoantibodies. The following results were obtained: ICA-IgG, 5, >80, and >80 JDF-U, respectively; GAD-Abs: >100 U/ml in all three measurements; IA2-Abs and IA-Abs: negative. During treatment, thyroid microsomal autoantibodies increased markedly (from 1:100 to 25,600 titer); thyroid-stimulating hormone was persistently normal. HLA class II typing revealed a genetic predisposition to insulin-dependent diabetes mellitus as demonstrated by the presence of DRB1* 04/08, DQ A1 52 Arg+/Arg+, and DQB1 57 N-Asp/Asp alleles. One year after the onset of insulin-dependent diabetes mellitus, the patient is still receiving 30 IU insulin daily; the liver function tests are normal and HCV-RNA is negative. These data support the hypothesis that, in predisposed patients, alpha-interferon therapy can enhance an ongoing autoimmune process against pancreatic beta-cells and induce overt insulin-dependent diabetes mellitus. We therefore suggest that, in patients with a documented predisposition to insulin-dependent diabetes mellitus, alpha-IFN therapy should be administered with caution.


The Lancet | 1983

COMPLEMENT-FIXING ADRENAL AUTOANTIBODIES AS A MARKER FOR PREDICTING ONSET OF IDIOPATHIC ADDISON'S DISEASE

Corrado Betterle; R. Zanchetta; Alfonso Trevisan; F. Zanette; B. Pedini; Franco Mantero; F. Rigon

In a prospective investigation of the role of adrenal autoantibodies (AA) in predicting the onset of idiopathic Addisons disease, 9 initially non-addisonian AA-positive autoimmune subjects were followed for 42 months. In 4 of these subjects Addisons disease developed within 1-31 months. A fifth had reduced adrenocortical reserve at the start and at the end of the investigation. An AA capable of fixing the membrane attack complex of complement [(C5-C9) F-AA] was detected before onset of the disease in the sera of the 4 patients in whom Addisons disease developed. (C5-C9) F-AA may be involved in the pathogenesis of idiopathic Addisons disease and may be regarded as a marker for individuals in whom idiopathic adrenal insufficiency is likely to develop.


Diabetologia | 1987

Islet cell and insulin autoantibodies in organ-specific autoimmune patients. Their behaviour and predictive value for the development of Type 1 (insulin-dependent) diabetes mellitus. A 10-year follow-up study

Corrado Betterle; Fabio Presotto; B. Pedini; L. Moro; R. S. Slack; F. Zanette; R. Zanchetta

SummaryTo evaluate the behaviour and predictive value of islet cell and insulin autoantibodies in patients with organspecific autoimmune diseases, we followed 21 non-diabetic subjects for a mean period of 84±27 months. Ten patients were persistently seropositive for complement-fixing islet cell antibodies and high titres of immunoglobulin G islet cell antibodies (≥ 1∶8). The prevalence of persistent insulin autoantibodies in this group was 67%. Seven patients (70%) developed Type 1 (insulin-dependent) diabetes mellitus after a latency period of 2–60 months. The predictive value of complement-fixing islet cell antibodies was 65%, and in the presence of both complement-fixing islet cell and insulin autoantibodies the predictive value rose to 76%. Eleven patients were seronegative for complement-fixing islet cell antibodies and had low immunoglobulin G islet cell antibodies titres (< 1∶8) that were either persistent or transient, or that fluctuated during follow-up. The prevalence of persistent insulin autoantibodies in this group was 45%; only one subject developed Type 1 diabetes. The predictive value of persistent islet cell antibodies (complement-fixing positive/negative) was 54%, and it rose to 70% when both islet cell and insulin autoantibodies were present. Individuals with only insulin autoantibodies or immunoglobulin G islet cell antibodies did not develop diabetes mellitus. A high frequency of HLA-DR3 and/or DR4 was found in patients who developed diabetes mellitus. Thus, the presence of both islet cell and insulin autoantibodies in patients with organ-specific autoimmune disease appears to confer the highest risk of progression toward Type 1 diabetes.


Cell and Tissue Research | 1990

Sertoli and Leydig cell numbers and gonadotropin receptors in rat testis from birth to puberty

Marino Bortolussi; R. Zanchetta; Paola Belvedere; Lorenzo Colombo

SummaryIn testes of rats from 2 to 60 days of age, we examined the number of Sertoli cells (SC) and Leydig cells (LC) as well as the binding of radioiodinated gonadotropins to frozen sections and homogenates. The number of SC per testis increased only during the first 2 postnatal weeks, whereas that of LC was stable up to days 7–10 and increased thereafter. The uptake of 125I-labelled human follicle-stimulating hormone (125I-FSH) to frozen sections was confined to sex cords or seminiferous tubules, while that of 125I-labelled human choriogonadotropin (125I-hCG) matched the distribution of LC in the interstitium. High affinity receptors for FSH and hCG were found in homogenates at all stages studied. The number of FSH receptors per testis increased steadily, whereas that of hCG receptors was low until days 7–10 and rose afterwards. Thus, SC in rat testis appear to proliferate in the presence of fetal LC during the first 2 postnatal weeks and to differentiate concomitantly with the emergence of the adult LC generation after day 10. The complement of FSH receptors in SC remains constant as they proliferate and increases after day 21 as they differentiate. The hCG receptor number is relatively fixed in each LC generation, being higher in adult compared to fetal LC.


Clinical Endocrinology | 2009

Evaluation of the autoimmune regulator (AIRE) gene mutations in a cohort of Italian patients with autoimmune‐polyendocrinopathy‐candidiasis‐ectodermal‐dystrophy (APECED) and in their relatives

Sara Cervato; Barbara Mariniello; Francesca Lazzarotto; Luca Morlin; R. Zanchetta; Giorgio Radetti; Filippo De Luca; Mariella Valenzise; Roberta Giordano; Daniela Rizzo; Carla Giordano; Corrado Betterle

Objective   Autoimmune‐polyendocrinopathy‐candidiasis‐ectodermal‐dystrophy (APECED) is a rare syndrome characterized by chronic candidiasis, chronic hypoparathyroidism and Addisons disease. APECED has been associated with mutations in autoimmune regulator (AIRE) gene. Our aim is to perform a genetic analysis of the AIRE gene in Italian APECED patients and in their relatives.


Andrologia | 2009

Microbial Flora in Semen of Asymptomatic Infertile Men

F. Busolo; R. Zanchetta; E. Lanzone; R. Cusinato

Summary: A microbiological examination has been carried out in 116 patients with unexplained infertility and with asymptomatic bacteriospermia. Organisms more frequently isolated were Staphylococcus epidermidis (81.9%), non hemolytic streptococci (23.3%), diphtheroids (25%) and alpha‐hemolytic streptococci (18.1%). None of the 103 patients were positive for C. trachomatis. Mycoplasmas were isolated in 56 (48.3%) of the 116 examined samples, U. urealyticum was present in 49 (42.2%), M. hominis in 3 (2.6%) and both species in 4 (3.5%) samples of examined fluids.


Clinica Chimica Acta | 2003

A sensitive non-isotopic assay for GAD65 autoantibodies.

Helen Brooking; Rossitza Ananieva-Jordanova; Clare Arnold; Marie Amoroso; Michael Powell; Corrado Betterle; R. Zanchetta; Jadwiga Furmaniak; Bernard Rees Smith

BACKGROUND A new ELISA for 65 kDa isoform of glutamic acid decarboxylase autoantibodies (GAD(65) Abs), which depends on GAD(65) Ab acting divalently and forming a bridge between immobilized GAD(65) and liquid-phase GAD(65)-biotin, is described. METHODS Sera (25 microl) were incubated in GAD(65)-coated ELISA plate wells followed by washing and incubation with GAD(65)-biotin. After a further wash step, GAD(65)-biotin bound was quantitated by addition of streptavidin peroxidase followed by tetramethylbenzidine. Assay calibration was with WHO reference preparation 97/550. RESULTS Using a cut-off for positivity of 5 units/ml, sera from 0.7% (2/300) healthy blood donors (HBDs), 100% (39/39) selected type 1 diabetes mellitus (DM) patients, 1.6% (1/62) type 2 diabetes mellitus patients and 3% (4/119) autoimmune disease controls were GAD(65) Ab positive in the ELISA. Levels of positivity in an immunoprecipitation assay (IPA) based on 125I-labelled GAD(65) (cut-off 25 units/ml) were 1%, 82%, 0% and 3%, respectively. ELISA inter-assay coefficients of variation (n=12) were 7.3%, 3.8%, 7.2% and 6.3% at 5.4, 40.8, 137 and 382 units/ml, respectively. CONCLUSIONS The ELISA we have described has sensitivity and specificity at least as high as current radioactive assays. It has good precision and handling making it suitable for routine use.


The Journal of Clinical Endocrinology and Metabolism | 2011

Premature Ovarian Failure in Patients with Autoimmune Addison's Disease: Clinical, Genetic, and Immunological Evaluation

G. Reato; Luca Morlin; S. Chen; Jadwiga Furmaniak; B. Rees Smith; Stefano Masiero; Maria Paola Albergoni; Sara Cervato; R. Zanchetta; Corrado Betterle

DESIGN The design of the study was to investigate the prevalence of the following: 1) premature ovarian failure (POF) in patients with autoimmune Addisons disease (AD); 2) steroid-producing cell antibodies (StCA) and steroidogenic enzymes (17α-hydroxylase autoantibodies and P450 side-chain cleavage enzyme autoantibodies) in patients with or without POF; and 3) the value of these autoantibodies to predict POF. PATIENTS The study included 258 women: 163 with autoimmune polyendocrine syndrome type 2 (APS-2), 49 with APS-1, 18 with APS-4, and 28 with isolated AD. METHODS StCA were measured by an immunofluorescence technique and 17α-hydroxylase autoantibodies and P450 side-chain cleavage enzyme autoantibodies by immunoprecipitation assays. RESULTS Fifty-two of 258 women with AD (20.2%) had POF. POF was diagnosed in 20 of 49 (40.8%) with APS-1, six of 18 (33.3%) with APS-4, 26 of 163 (16%) with APS-2, and none of 28 with isolated AD. In patients with APS-1 and APS-4, POF developed after AD, whereas it preceded AD in patients with APS-2. StCA were detected in 31 of 43 with POF (72%) and 51 of 198 without POF (25.7%). StCA were present in 22 of 38 with APS-1 (57.9%) (11 of 13 with POF); in five of 13 with APS-4 (38.5%) (three of four with POF); in 53 of 162 with APS-2 (32.7%) (17 of 26 with POF), and in one of 28 isolated AD patients (3.6%). Twelve of 13 patients with POF with a duration less than 5 yr (92.3%) and 18 of 25 with duration longer than 5 yr (72%) were StCA positive. Twenty-eight of 31 with POF (90.3%) were positive for at least one steroidogenic antibody. Forty-one women with AD less than 40 yr were followed up for a mean period of 9 yr. Eight of 21 women (38%) positive or seroconverted for steroidogenic autoantibodies developed POF at a mean age of 23 yr (six with APS-1, one with APS-2, and one with APS-4), and none of the 20 patients negative for steroidogenic autoantibodies developed POF. CONCLUSIONS This study indicates that AD is frequently associated with POF and that steroidogenic antibodies are markers of patients with POF. Steroidogenic autoantibodies are predictive markers of POF in patients with AD.


Fertility and Sterility | 1984

Mycoplasmic localization patterns on spermatozoa from infertile men

Franco Busolo; R. Zanchetta; Giulio Bertoloni

Two mycoplasmas have been observed with increasing frequency in patients with genitourinary disorders: Mycoplasma hominis and Ureaplasma urealyticum. Mycoplasma cells of both these species have been demonstrated to be capable of attaching to human spermatozoa of infertile patients. The mechanisms for the association of infertility and mycoplasma infection have not been established. The main objective of this article was to explain the significance of some morphologic features of spermatozoa of patients with unexplained infertility using light and electron microscopy. These studies and quantitative analysis of ureaplasmas in the semen indicate that at least two patterns can be seen. Frequently, sphere-shaped particles adhering mainly to the midpiece of spermatozoa were detected. In a second, more complex pattern ureaplasmas were seen inside a swollen zone on the midpiece, which suggests that the infection does not occur in the urethra, but at another unknown site. Furthermore, the sphere-shaped particles cannot be associated with ureaplasmas because their titers in the semen of infertile patients were much lower than those expected.


Andrologia | 2009

Immunological and clinical study in patients after spermatic cord torsion

I. Mastrogiacomo; R. Zanchetta; P. Graziotti; C. Betterle; P. Scrufari; A. Lembo

Immunologische und klinische Untersuchungen bei Patienten nach Samenstrangtorsion

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