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Biomedical subjects

C Besana

Publications and source records attributed to C Besana.

At least 37 records · Page 2Linked to original sources

Relation between enzymatic activities and the degree of malignancy of human lymphomas.

The relationship between the intracellular levels of DNA polymerase alpha (DP-alpha), adenosine deaminase (ADA) and lactate dehydrogenase (LDH) and the degree of malignancy of human lymphomas was investigated. Twelve non-neoplastic lymph nodes and 88 malignant lymphomas were examined. For non-Hodgkin's lymphomas (NHL) the low or high grade of malignancy was established according to three classifications: the Rappaport, the Kiel and the Working Formulation for Clinical Usage, with the latter also recognizing an intermediate grade group. Non-neoplastic lymph nodes had significantly lower levels of all the three enzymes than those found in high-grade malignant NHL (the P value ranged from less than 0.02 to less than 0.001). Hodgkin's disease, a slowly evolving neoplasia, showed lower levels of DP-alpha (P less than 0.001) and ADA (P less than 0.001), but not of LDH, than high-grade NHL. Among NHL, whatever classification was used, the low-grade malignant lymphomas had significantly lower levels than the high-grade ones for all the three enzymes (P less than 0.005 or P less than 0.001). The intermediate-grade group of the Working Formulation differed from the high-grade group for DP-alpha (P less than 0.01) and ADA (P less than 0.02) but not for LDH. It differed from the low-grade group only for ADA (P less than 0.005). Lymphoblastic and Burkitt's lymphomas were the groups with the highest levels of the three enzymes. Among low-grade lymphomas very low values were found in the histological entities defined as DLWD in the Rappaport classification, CLL and lymphoplasmacytoid immunocytoma in the Kiel classification and small lymphocytic (group A) in the WF. The levels of all enzymes in these histotypes were always significantly different from the other low-grade histotypes, and from the intermediate-grade ones of the WF. In the Kiel classification polymorphous lymphoplasmacytoid lymphoma, recently recognized as a group with a quite aggressive clinical course, was characterized by high levels of all three enzymes.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Deaminase↗

Theophylline induced non specific suppressor activity in human peripheral blood lymphocytes.

It is wellknown that theophylline yields phenotypic changes on suppressor cells. In the present study we investigated the possibility that theophylline could directly induce a suppressor activity on a lymphocyte subpopulation. We observed that a short preincubation (120 min at 37 degrees C) with theophylline (1mM) activates human peripheral blood lymphocytes to suppress mitogenic response of autologous cells. This activity was not evident on a T cell subpopulation depleted of theophylline-sensitive (T-sens) lymphocytes. Theophylline mediated suppressor activity is only present in the Concanavalin A stimulated cultures, thus suggesting a synergism between Concanavalin A and theophylline in the expression of non specific suppression. Moreover we observed that after a 24 hrs preincubation of lymphocytes in complete culture medium there was a complete loss of theophylline-induced suppression. Such a preincubation time also produced a decrease in the theophylline-mediated enhancement of intracellular 3', 5' cyclic adenosine monophosphate levels and the impairment of E-rosette formation, suggesting that theophylline acts mainly on a "short-lived" suppressor lymphocyte subset.

Adult↗

Abnormal OKT4/OKT8 ratio and deranged capping in ataxia-telangiectasia.

Two sisters with ataxia-telangiectasia (A-T) and their parents were investigated for some parameters related to immunological functions. We found a decrease of total mature T lymphocytes, a decrease of OKT4+ helper-inducer T subset, and normal values of OKT8+ suppressor-cytotoxic T subset; a normal decrease of E rosette formation after incubation in vitro with theophylline, with a lowered E rosette capacity in one patient. The responses to phytohemagglutinin (PHA)and concanavalin A (ConA) were lowered. In addition we observed a reduction of basal capping of B lymphocytes in one patient and in her parents: this phenomenon could be related to cytoskeletal disorders, possibly involved in the pathogenesis of the disease.

Adolescent↗

Studies of the pathophysiology of acquired von Willebrand's disease in seven patients with lymphoproliferative disorders or benign monoclonal gammopathies.

In seven patients with acquired von Willebrand's disease (AvWD) associated with lymphoproliferative disorders or benign monoclonal gammopathies, the platelet contents of von Willebrand factor antigen and ristocetin cofactor (vWF:Ag and vWF:RiCof, respectively) were normal. All the multimers of vWF:Ag could be seen in the 1.6% SDS-agarose gel electrophoresis patterns of plasma and platelet lysates. Infusion of 1-deamino-8-D-arginine vasopressin (DDAVP) augmented plasma levels of vWF:Ag and vWF:RiCof of all patients and corrected prolonged bleeding times (BT). However, compared with patients with congenital vWD type I and comparable degrees of baseline abnormalities treated in the same way, vWF:Ag and vWF:RiCof were increased less and cleared more rapidly from plasma and the BT remained normal for a shorter period of time. These studies provide evidence that these AvWD patients have qualitatively normal vWF in plasma, but at lower concentrations, that vWF in platelets is normal both qualitatively and quantitatively, and that cellular vWF can be rapidly released into plasma by DDAVP to correct the hemostatic abnormalities. However, vWF is removed rapidly from plasma, making the correction more transient than in congenital vWD type I.

Adult↗

Spontaneous "in vitro" variations of theophylline sensitivity in human peripheral blood lymphocytes.

Theophylline reversibly inhibits E rosette formation by a portion of human circulating T lymphocytes. We investigated the effect of theophylline on E rosette formation and intracellular content of cyclic nucleotides (cAMP, cGMP). When the amine is added to 15 human healthy donors' lymphocytes either before or after 24 hours of culture at 37 degrees C, in absence of mitogens, a portion of theophylline-sensitive T cells spontaneously becomes theophylline-resistant after 24 hours of culture. While the intracellular content of cAMP does not significantly vary, the ability of theophylline to induce an increase of cAMP appears to be impaired after 24 hours of culture. The possible correlation between theophylline resistance and impaired turnover of cAMP in the cultured lymphocytes is discussed.

Cyclic AMP↗

[Evaluation of some inflammatory and immune parameters in juvenile rheumatoid arthritis during the acute phase and in remission].

A serologic study was carried out in 27 children.-- 12 females and 15 males -- affected with juvenile rheumatoid arthritis (JRA), systemic and polyarticular type, in active phase and in remission. Beside the routine assays (ESR and haemometry), a dosage of serum immunoglobulins (IgA, M, G) and complement components (C3 and C4) was carried out; antinuclear antibodies with immunofluorescence, rheumatoid factors with classical method (latex test and Waaler-Rose reaction) and antigamma factors (AGGF) according to modified Schur's method were looked for. Polymorphonuclear function was assayed employing NBT test, phagocytosis and killing with Klebsiella. The results confirmed that the most reliable activity index is the ESR, while the WBC count is move variable and that the rheumatoid factors according to the usual techniques are almost always absent. As a whole, in JRA the levels of IgM, IgG, IgM-AGGF, C4 assayed higher than in controls. In the different subgroups, the systemic disease is characterized by higher serum IgA and IgG-AGFF. The PMN function was globally normal.

Acute Disease↗

[Demonstration of a granulocyte defect in aged persons correlated with the presence of autoantibodies].

Assessment of PMN leukocyte function and search for autoantibodies were performed in 36 aged human subjects (more than 60 years of age) and in 15 younger controls (40 to 60 years of age). Autoantibodies were found in 15 of the 36 aged subjects, and in none of the controls. Leukocyte function defects were therefore correlated to old age and to markers of autoimmunity. Phagocytosis of bacteria was significantly impaired in both groups of old-aged subjects, irrespective to the presence or absence of autoimmunity. Intracellular killing of bacteria was shown to be normal in all the examined subjects. Nitroblue tetrazolium reduction by resting and latex-stimulated leukocytes was significantly impaired only in the group of old-aged subjects with autoimmunity. These leukocyte function defects are similar to those already described in human autoimmune diseases -- particularly S.I.E. -- and confirm the possible association between P.M.N. dysfunction and autoimmunity.

Adult↗

Immunological investigation and immunotherapy approaches in cancer patients.

The Authors report the preliminary results of a two-step far-reaching investigation carried out on cancer patients to study: 1) the immune conditions of the patients and establish, by a thorough immune monitoring, employing tests of humoral immunity (tetanus toxoid response), of delayed immunity (BCG test, PHA-lymphocyte blastogenesis, MIF release, skin window) and macrophage immunity (skin window), the chemotherapy effects on the immune conditions and the most suitable time to carry out immunotherapy; 2) the immunotherapeutic results which can be obtained with three different immunogens (BCG, C. parvum and ribonucleotides). The results obtained in the first part of the investigations pointed out the usefulness of the tests adopted to follow up the evolution of the immunological reactivity in patients submitted to chemotherapy, while the results of the immunotherapeutic trial show a preliminary character and, at present, do not allow definitive conclusions. Carefully planned and randomized studies are at present under way to establish, more thoroughly, the optimal modalities and the real possibilities of the immunotherapy performed with C. parvum and ribonucleotides in cancer patients.

BCG Vaccine↗

Effects of short-term lithium treatment on peripheral blood lymphocytes and granulocytes in healthy volunteers.

The effects of a short-term treatment with lithium carbonate on lymphocytes and granulocytes were studied in six normal subjects. The lithium effects are related to a direct, immediate and quickly reversible action of the drug on the bone marrow, as demonstrated by the granulocyte number and variations in Arneth's index. Although lymphocyte and granulocyte functions do not seem to be affected by lithium when investigated by the usual methods, the ability of the drug to counteract the theophylline-induced inhibition of cellular functions would suggest that lithium acts mainly through the modulation of intracellular levels of cyclic nucleotides. This is confirmed by evaluation of cellular cyclic 3',5'-adenosine monophosphate (cAMP). The above hypothesis could explain the quick onset and loss of lithium action on granulopoiesis.

Adult↗

Primary antiphospholipid syndrome and neurologic events.

The occurrence of lupus anticoagulant and anticardiolipin antibodies was demonstrated in a girl affected by recurrent episodes of visual disturbances, with ophthalmologic evidence of visual impairment and sometimes accompanied by migraine. Systemic lupus erythematosus was excluded on the basis of both clinical and serologic criteria and the diagnosis of primary antiphospholipid syndrome was made. Vascular pathogenesis was suggested by the characteristic symptoms. The serologic demonstration of antiphospholipid antibodies made it possible to relate the illness to an immune-mediated thrombotic tendency. This patient demonstrated that the diagnosis of primary antiphospholipid syndrome must always be considered in focal cerebral or retinal ischemia in childhood.

Antibodies, Anticardiolipin↗