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Biomedical subjects

R Invernizzi

Publications and source records attributed to R Invernizzi.

At least 127 records · Page 7Linked to original sources

The amyloidosis.

The clinical and pathological features of amyloidosis are examined in the light of a classification based on anatomical models of amyloid distribution: 1) generalised amyloidosis, including primary and secondary sporadic forms, hereditary and familial amyloidosis, and senile amyloidosis; 2) local amyloidosis, including amyloid tumours, neoplasia with amyloid stroma, and other forms. The nature of amyloid is described. Morphological, ultrastructural, biochemical and immunochemical research has shown that: 1) amyloid is a fibrillar protein with a typical EM and X-ray diffraction appearance; 2) two main types of amyloid proteins exist, one related to Ig light chains and found in primary forms and in association with myeloma, the other (called AA proteins) being the main component of secondary forms and certain types of familial amyloidosis; 3) serum proteins structurally related to the AA proteins may be used as amyloid precursors. The cause and mechanisms of amyloid production are becoming clearer. In particular, a relation with the production of Igs has been established. Improved methods for the diagnosis and treatment of the disease will throw more light and the nature of amyloid and its protein precursors.

Age Factors↗

Expression of p170 protein in multiple myeloma: a clinical study.

The expression of the p170 multidrug resistance protein by bone marrow plasma cells (BMPC) was assessed at clinical presentation in 53 patients with multiple myeloma (MM) using the C219 monoclonal antibody. Twenty-two of the 53 (41 per cent) patients had variable aliquots (1-60 per cent, median = 6 per cent) of p170+ BMPC by immunocytochemistry. Five of 10 patients studied using bivariate flow cytometry had both diploid and hyperdiploid (DNA index ranged from 1.2 to 1.5) BMPC with hyperdiploid clones having significantly greater p170 expression than diploid ones. Of the 37 patients evaluated for a response, 20 (54 per cent) had responded to induction chemotherapy. The presence of p170+ BMPC was a negative indicator for achieving response. The response rate was 75 per cent for p170- and 25 per cent for p170+ cases (p < 0.01), with no difference on the basis of treatment schedule (melphalan and prednisone, 24 patients; peptichemio, vincristine and prednisone, 13 patients). No difference in response and survival duration was found between p170+ and p170- patients. In six of nine patients studied both at diagnosis and following induction chemotherapy the p170+ BMPC% increased irrespective of the type of treatment or outcome.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Effect of 5-HT1A receptor antagonists on citalopram-induced increase in extracellular serotonin in the frontal cortex, striatum and dorsal hippocampus.

The aim of the present study was to compare the effects of citalopram, either alone or combined with 5-HT1A receptor antagonists, on extracellular serotonin levels in brain regions innervated by the dorsal or median raphe nuclei. Using intracerebral microdialysis in awake rats with separate probes in the frontal cortex or dorsal hippocampus, we studied the ability of 8 mg/kg s.c. (-)penbutolol, a beta-adrenoceptor antagonist with antagonist action at 5-HT1A and 5-HT1B receptors, and 0.3 mg/kg s.c. WAY-100635, a selective 5-HT1A receptor blocker, to modify the effect of 1 and 10 mg/kg i.p. citalopram on extracellular serotonin. Both doses of citalopram had more effect on extracellular serotonin levels in the dorsal hippocampus than in the frontal cortex. The effect of 1 mg/kg citalopram was significantly potentiated by (-)penbutolol in the frontal cortex only, but a clear-cut potentiation of the effect of citalopram was seen in both regions at a dose of 10 mg/kg. The effect of 10 mg/kg citalopram was potentiated by WAY-100635 in the frontal cortex but not in the dorsal hippocampus. In a second set of experiments, the combined effect of WAY-100635 and citalopram was studied in the same rat implanted with vertical probes in the striatum and dorsal hippocampus. Citalopram (1 and 10 mg/kg i.p.) raised extracellular serotonin to a similar extent in both regions. However, 0.3 mg/kg s.c. WAY-100635 potentiated the effect of 10 mg/kg citalopram in the striatum but not in the dorsal hippocampus. The results suggest that only a combined blockade of 5-HT1A and 5-HT1B receptors potentiates the effect of citalopram on extracellular concentrations of serotonin in the dorsal hippocampus. The findings may be relevant in designing clinical trials aimed at enhancing the antidepressant action of selective serotonin re-uptake inhibitors by combining them with serotonin receptor antagonists.

Animals↗

Meningeal involvement in multiple myeloma: report of a case with cytologic and immunocytochemical diagnosis.

BACKGROUND: Multiple myeloma (MM) with meningeal involvement is a very rare phenomenon. Only 37 cases of plasma cell neoplasia (MM and plasma cell leukemia) with meningeal involvement have been reported. CASE: A 60-year-old male with stage IIIA light lambda chain MM returned nine months after the diagnosis with back pain, lower right extremity paresthesias and gait disturbance. A lumbar puncture revealed atypical plasma cells in the cerebrospinal fluid (CSF), and immunocytochemical studies showed a cytoplasmic monoclonal light lambda chain. A diagnosis of myelomatous meningitis was made, and the patient received intrathecal chemotherapy and craniospinal irradiation. He died six months after the diagnosis of meningeal disease. CONCLUSION: The present case and a review of the literature show that clinical manifestations of meningeal myeloma are non-specific. MM with meningeal involvement is accompanied frequently by circulating atypical plasma cells or plasma cell leukemia. Atypical plasma cells in the CSF are an important finding for the diagnosis of meningeal myeloma, and their neoplastic nature can be best identified by immunocytochemical analyses. Patients with meningeal myelomatosis can have a good response to treatment initially, but their prognosis is poor.

Fatal Outcome↗

Rhabdomyosarcoma with primary osteolytic lesions simulating non-Hodgkin's lymphoma.

We report the case of an 8-year-old child presenting with the pathological fracture of two vertebral bodies due to bone lytic lesions. Physical and instrumental examinations did not show any further evidence of disease. However, bone marrow aspirate showed an infiltrate of poorly differentiated cells. When the child was transferred to the Department of Pediatrics, lymphoblastic leukemia was suspected. Although the morphology of the bone marrow biopsy could have suggested a lymphoblastic lymphoma, further immunochemical and immunological studies together with the study of tissue surface antigens resulted in a diagnosis of embryonal rhabdomyosarcoma with an unusual presentation.

Antigens, Differentiation↗

Granular acute lymphoblastic leukemia in children. "Aieop Cooperative Group for Cytology of Acute Leukemias".

BACKGROUND: Granular acute lymphoblastic leukemia (ALL) is a rare morphological variant of ALL, characterized by cytoplasmic azurophil granules or inclusions, positive for aspecific esterase and acid phosphatase, with heterogeneous features at the ultrastructural level. METHODS: In an attempt to determine whether the presence of granules or inclusions marks a biologically distinct variety of ALL with peculiar clinical features, a prospective morphological review was undertaken of children entering AIEOP protocols for ALL in the period from 1985 to 1989. RESULTS: Of 531 cases examined, 16 (3%) were found to have greater than 1% granular bone marrow blasts, with 7 cases (1.3%) having greater than 10%. The presence of granules or inclusions was associated with the immunophenotype of "common" ALL. There was no clear association with FAB type L1 or L2 nor with particular clinical or hematological findings at presentation. Complete remission was achieved in all cases; one patient died of infection in remission at 3 months and 2 patients relapsed after 12 and 32 months, respectively, while the others are still in remission after a minimum follow-up of 24 months. CONCLUSIONS: In conclusion, granular morphology seems to have no prognostic importance in children ALL.

Acid Phosphatase↗

B-cell acute lymphoblastic leukemia (B-ALL): a report of 17 pediatric cases.

BACKGROUND AND METHODS: B-cell acute lymphoblastic leukemia (B-ALL) presents FAB L3 morphology and surface Ig, CD19, CD20, CD24. This pattern may show some morphological and immunological heterogeneity. Seventeen pediatric cases of B-ALL at onset, treated in twelve AIEOP Centers (Italian Association for Pediatric Hematology and Oncology), are presented. RESULTS AND CONCLUSIONS: Clinical and hematological features were characterized by low WBC counts at presentation, high M/F ratio, older age and association with extramedullary involvement. The overall survival curve at 78 months is 40%. All patients showed blasts positive for surface Ig (sIg), DR, CD19, and CD24. Ten/17 cases presented the classical features of B-ALL: FAB L3 morphology, sIg+ restricted to light chains, CD20+, cytoplasm mu (c mu)-, CD10-, TdT-. The remainder showed some differences in this pattern, such as non-L3 morphology (3 cases), absence of CD20 (3 cases), CD10+ (4 cases), TdT+ (3 cases), c mu+ (1 case), lack of surface light chains (1 case). This rare ALL subset seems to be characterized by a high phenotype heterogeneity, indicating various degrees of differentiation.

Adolescent↗