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Biomedical subjects

R Manna

Publications and source records attributed to R Manna.

At least 37 records · Page 2Linked to original sources
PubMed1998

Delayed hypersensitivity to aminopenicillins is related to major histocompatibility complex genes.

BACKGROUND: Although in some cases delayed hypersensitivity may be observed, beta-lactam antibiotics frequently induce immediate allergic IgE-mediated reactions with the specificity localized in the acyl-side chain structure. Generally, delayed immunologic reactions are related to sensitized T lymphocytes and major histocompatibility complex restricted. OBJECTIVE: To investigate the prevalence of HLA class I and II antigens in patients with delayed hypersensitivity to aminopenicillins in order to evaluate a relationship between major histocompatibility complex immune response genes and aminopenicillins hypersensitivity. METHODS: We assessed 24 patients with history of delayed hypersensitivity to aminopenicillins using (1) skin test with penicilloyl polylysine, minor determinant mixture, benzylpenicillin, amoxicillin, and ampicillin; (2) patch tests with benzylpenicillin, amoxicillin, and ampicillin; (3) RAST for penicilloyls G and V; and (4) oral challenges with amoxicillin, ampicillin, and penicillin V in 18/24 patients. All patients were typed by microlymphotoxicity standard test for HLA class I and II antigens. Statistical analysis by chi2 test 2 x 2 contingency tables, according to Svejgaard, were used for comparison between patients and random Italian population (522 subjects). RESULTS: In the patients group we found higher prevalence of HLA A2 (12/24 = 50%, RR = 6.76 P < .001, EF = 0.425), DRw52 (20/24 = 83.3%, RR = 9.28, P < .001, EF = 0.74), and lower frequency of DR4 (3/24 = 12% ns). CONCLUSIONS: These data suggest that the immune mechanisms involved in adverse reactions to aminopenicillins in vivo are related to genetic markers of immune response and confirms that the presentation of penicillin-hapten determinants to lymphocyte is major histocompatibility complex restricted.

Adolescent↗
PubMed1998

Sudden hearing loss in a patient hepatitis C virus (HCV) positive on therapy with alpha-interferon: a possible autoimmune-microvascular pathogenesis.

Alpha interferon (alpha-IFN) is used for the treatment of various systemic disorders. Side-effects of alpha-IFN therapy can involve numerous organ systems, but sudden hearing loss has only once been recorded. We report a case of sudden hearing loss occurring in a patient with chronic hepatitis C treated with alpha-IFN and recovered five days after the discontinuation of this agent. This is the first record of anti-endothelial cell antibodies detection in a patient with sudden hearing loss. The finding of anti-endothelial cell antibodies suggests an association between sudden hearing loss and microvascular damage during interferon therapy.

Antiviral Agents↗
PubMed1998

Anticardiolipin antibodies in giant cell arteritis and polymyalgia rheumatica: a study of 40 cases.

The occurrence and clinical value of anticardiolipin antibodies (aCL) were studied in 33 patients with giant cell arteritis (GCA) and in seven patients with polymyalgia rheumatica (PMR), at onset and during follow-up. aCL were present in 19/40 (47.5%) GCA/PMR cases, most of them of the IgG isotype, whereas all controls (21 subjects) were aCL negative. The presence of aCL was not associated with inflammatory parameters or clinical signs of arteritis; however, they disappeared in a significant percentage (56%) of patients during steroid therapy. No correlation was found between ischaemic events and aCL, suggesting that they are not important for the development of vascular complications in GCA/PMR patients. Moreover, a retrospective evaluation of our data showed a correlation between aCL positivity and anaemia, whose significance remains to be elucidated.

Adult↗
PubMed1997

Schizophrenic symptoms and SPECT abnormalities in a coeliac patient: regression after a gluten-free diet.

A 33-year-old patient, with pre-existing diagnosis of 'schizophrenic' disorder, came to our observation for severe diarrhoea and weight loss. Use of single photon emission computed tomography, (99mTc)HMPAO SPECT, demonstrated hypoperfusion of the left frontal brain area, without evidence of structural cerebral abnormalities. Jejunal biopsy showed villous atrophy. Antiendomysial antibodies were present. A gluten-free diet was started, resulting in a disappearence of psychiatric symptoms, and normalization of histological duodenal findings and of (99mTc)HMPAO SPECT pattern. This is the first case in which, in an undiagnosed and untreated coeliac patient with psychiatric manifestations, the (99mTc)HMPAO SPECT demonstrated a dysfunction of frontal cortex disappearing after a gluten-free diet.

Adult↗
PubMed1997

Leucocytoclastic vasculitis associated with hepatitis C virus antibodies.

The actiopathogenesis of leucocytoclastic vasculitis is still unknown, but recently hepatitis C virus (HCV) has been suggested as trigger of autoimmunity. We report a case of a 26-yr-old patient with purpura due to leucocytoclastic vasculitis associated with hepatitis C virus infection. Laboratory findings showed AST, ALT, gamma GT within normal limits, positive antibodies to HCV (IIF and Riba II) and polymerase chain reaction for HCV RNA. Anti-nuclear antibodies, IgG and IgM anti-cardiolipin antibodies, anti-platelet antibodies and anti-neutrophil cytoplasmic antibodies with perinuclear pattern were also present. A skin biopsy specimen of a purpuric lesion showed leucocytoclastic vasculitis with small vessel thrombosis and perivascular deposition of IgM and fibrinogen on immunofluorescence study. This case shows a role of HCV in leucocytoclastic vasculitis; it is possible that this HCV can induce autoimmunity independently of cryoglobulins and liver involvement.

Adult↗
PubMed1996

Recurrent perimyocarditis following a non penetrating chest trauma. A case report.

A young man, after a non penetrating chest trauma, developed recurrent episodes of fever, chest pain, pleural and pericardial effusion, without laboratory evidence of viral infections, or positivity for conventional autoimmunity markers. A clearcut positivity for more specific cardiac autoantibodies, against Beta 1 adrenoceptors (AB1AA), was found (at all dilutions from 1:20 to 1:160). A full dosage of Prednisone rapidly relieved all symptoms, whereas antibiotic therapy had been previously uneffective. At a follow-up control after three months, the patient was healed and AB1AA were positive only at dilutions 1:20 and 1:40. As silent viral myocarditis was apparently ruled out by serological negativity for viral infections, it is possible that autoimmunity could have played a primary pathogenetic role for the development of pericarditis in this patient. Further work is needed to ascertain whether or not AB1AA detection could be a specific marker of cardiac autoimmunity phenomena.

Adult↗
PubMed1992

Nicotinamide treatment in subjects at high risk of developing IDDM improves insulin secretion.

Nicotinamide (NCT) has been shown to be effective in preventing the onset of type 1 diabetes mellitus (IDDM) in mice with non-obese diabetic (NOD) and beta cell damage, mediated by the diabetogenic agents including streptozotocin. NCT therapy in man has been shown to have a beneficial effect on the remission phase of IDDM, and its use is safe. In this open pilot trial we therefore studied the effect of oral NCT administration on insulin secretion rate and islet-cell antibody (ICA) titres in IDDM high risk subjects. NCT (25 mg/10 kg bw) was administered in 6/13 high risk patients identified by a family screening programme. Those subjects tested after eight months without treatment showed a decreasing secretion in comparison to onset baseline (56,1 +/- 37.8 versus 35,5 +/- 12.2), whereas the treated subjects showed an increasing insulin secretion after treatment (26 +/- 10 versus 50.2 +/- 26.6), in spite of ICA persistence. Statistical analysis shows an increased insulin secretion in the treated group versus the untreated group (chi 2 = 3.899, P = 0.048). No side-effects were observed. We conclude that NCT may repair beta-cell function in high risk subjects too if damage is not too severe; furthermore, the effect seems not to be mediated by an immune mechanism.

Adolescent↗
PubMed1991

Relationship between urinary neopterin excretion and islet cell antibodies in type 1 (insulin-dependent) diabetes.

Neopterin is specifically produced by interferon-activated macrophages, and it may be considered a marker of cellular immunity. In 40 newly diagnosed and 38 longer standing type 1 (insulin-dependent) diabetics the relationship between urinary neopterin levels and islet cell antibodies (ICA) was investigated. Raised urinary neopterin levels were found in 30 ICA positive (mean +/- SD: 729.8 +/- 602.1 mumol/mol creatinine, p = 0.0001) and 10 ICA negative (433.4 +/- 191.2 mumol/mol creatinine, p = 0.0005) diabetics at onset of disease compared with age-matched control subjects (118.1 +/- 33.2 mumol/mol creatinine). No significant difference in urinary neopterin levels was observed between diabetic groups. After the first stages of disease (greater than 5 months from onset), a significant difference (p = 0.0002) in urinary neopterin excretion was found between longer standing ICA positive patients and controls, but not between ICA negative diabetics and controls. In longer standing diabetics, neopterin levels were significantly higher in ICA positive patients than in ICA negative patients (544.6 +/- 341.3 versus 201.7 +/- 180 mumol/mol creatinine, p = 0.0002). No correlation between newly diagnosed or longer standing patients and HbA1c levels was found. Our results suggest that increased neopterin excretion in type 1 diabetes seems to be a sensitive indicator for the activation of cell-mediated immunity even when ICA are undetectable.

Adolescent↗
PubMed1990

[Immunogenetic and functional study of first-degree relatives of patients with type I diabetes mellitus for identifying prediabetic subjects].

Insulin dependent diabetes mellitus is an autoimmune disease with HLA-related genetic susceptibility. There is a latent phase before overt disease. During this phase islet cell antibodies (ICA) as a marker of humoral autoimmunity are detected and i.v. glucose tolerance test (IVGTT) is decreased. The aim of our work was to correlate IVGTT, HLA typing and ICA testing in all siblings of IDDM patients in order to identify high risk subjects (HRS). IVGTT showed significantly lower insulin levels in siblings vs controls (P less than 0.0001). This phenomenon could be caused by HLA unrelated genetic predisposition to low insulin secretion. Insulin level values of ICA+ siblings were lower than those of ICA- siblings, even if the difference was not significant.

Autoantibodies↗
PubMed1990

ABO blood groups and cancer of the pancreas.

Few investigations discussing an association between ABO blood groups and pancreatic cancer exist. We have selected a series of 224 patients with histologically-confirmed pancreatic cancer, and their ABO blood groups distribution was compared with two control groups: 7086 patients with various diseases (Group 1) and 7320 voluntary blood donors (Group 2). There was an increased number of pancreatic cancer among the patients with blood group B (relative risk 1.5 vs Group 1 p = 0.021; 1.7 vs Group 2 p = 0.0025) and a decreased number in patients with blood group O, when compared with the two control groups.

ABO Blood-Group System↗
PubMed1990

Extramedullary hematopoiesis involving the esophagus in myelofibrosis.

In this report, we describe a case of myelofibrosis with myeloid metaplasia; a 53-yr-old man was splenectomized for a massively enlarged spleen in which multiple foci of myeloid metaplasia were histologically demonstrated. The patient was referred to us for endoscopic examination, following the repeated occurrence of melena. Upper gastrointestinal endoscopy revealed two active ulcerative lesions in the bulb, and only a moderate erythema in the lower third of the esophagus, which showed no varices. There was no endoscopic evidence of active or recent bleeding. Subsequent histologic examination of biopsies taken from the esophageal lesion surprisingly revealed the presence of hematopoietic tissue.

Biopsy↗
PubMed1988

Effect of fenfluramine on insulin/growth hormone ratio in obese subjects.

Obesity is characterized by increased levels of insulin and by subnormal growth hormone (GH) release. Insulin/GH ratio is significantly higher in obese than in lean individuals. Fenfluramine, an anorectic drug, may have some effects on hypothalamic-pituitary function and on insulin secretion, possibly through a serotonergic stimulation. The aim of this work was to study the effects of fenfluramine on the insulin/GH ratio after arginine in obese subjects. Ten volunteer obese females were studied; 10 volunteer women were the normal weight controls. All subjects were given placebo and fenfluramine (60 mg p.o.) in a randomized order and after 120 min underwent arginine infusion (25 g i.v. for 30 min). Blood samples were taken every 30 min until 270 min for GH and insulin radioimmunoassay. In the obese group the GH response to arginine was significantly lower than in controls. Fenfluramine administration restored the subnormal GH response to arginine in obese subjects. Arginine infusion provoked a greater insulin secretion in obese subjects than in lean individuals. Fenfluramine administration diminished the insulin response to arginine. Fenfluramine did not modify the insulin/GH ratio in controls while it significantly lowered the insulin/GH ratio in obese subjects. Because insulin promotes fat and carbohydrate storage while GH stimulates lipolysis, the combination of high insulin and low GH concentrations may worsen the obese condition. A lower insulin/GH ratio can be useful in the treatment of obesity.

Adult↗
PubMed1988

Glucagon and glucose tolerance in liver cirrhosis.

The present study was undertaken in order to establish the significance of glucagon in glucose intolerance in liver cirrhosis. The plasma glucose response to an oral glucose load (75 g) was determined in 10 control subjects and in 10 cirrhotic patients, after infusions of: glucagon (3 ng.kg-1.min-1) or saline (154 mmol/l); somatostatin (SRIH) (500 micrograms/h); and SRIH plus glucagon (3 ng.kg-1.min-1). Glucagon infusion did not impair glucose tolerance, neither in normal subjects nor in patients with cirrhosis. On the other hand, in both groups glucose tolerance was impaired by SRIH infusion, presumably owing to an absolute insulin deficiency. Both in normal subjects and in cirrhotic patients, SRIH plus glucagon infusion further impaired glucose tolerance, presumably as a result of excess glucagon and concomitant insulin deficiency. In conclusion, our data show that hyperglucagonemia is not an important factor in the development of the glucose intolerance in patients with hepatic cirrhosis.

Adult↗