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Vitamin A affects the antibody responses and may affect phagocytic function and properdin levels. Pyridoxine deficiency impairs nucleic acid synthesis and depresses antibody formation, delayed hypersensitivity reactions and the ability of phagocytes to kill bacteria. Pantothenic acid deficiency impairs antibody formation. Vitamin C deficiency increases the incidence of infection, primary by a negative influence on reparative processes. Deficiencies of other vitamins either have not been sufficiently studied or have a variable effect. Moreover, even substances which for their biosynthesis require an adequate vitamin supplementation may exert immunomodulatory influences. With this respect the authors report their results on the influence of L-carnitine on the immune system. L-carnitine increases the proliferative responses of both murine and human lymphocyte following mitogenic stimulation and increase polymorphonuclear chemotaxis. Furthermore, L-carnitine, even at minimal concentrations, neutralizes the lipid induced immunosuppression.

We present the results of sensitivity of 191 Gram-negative bacteria towards the following antibiotics: aminoglycosides (amikacin, gentamicin, tobramycin, netilmicin), cephalosporines (moxalactam, cefotaxime, ceftazidime) and piperacilline obtained by agar diffusion method (Kirby-Bauer) versus automatic system MS 2 Abbott. Essential accord expressed in percentage is for amikacin 96%, for gentamicin 93%, for moxalactam 91%, for tobramycin 95%, for cefotaxime 92%, for piperacilline 89%, for netilmicin 90%, for ceftazidime 92. Full accord gives more discrepant results especially for cephalosporins. For aminoglycosides no significative differences were observed between the two methods. For cephalosporins the incidence of discordance was a little more high. A better sensitivity was obtained by Kirby-Bauer method versus automatic system, which can be considered a therapeutical tool as it furnishes rapidly (4 hours) MIC values, useful to establish antibiotic doses.

A group of 173 subjects affected by congenital clotting factor deficiencies was evaluated with regard to the impact of HIV infection. On the whole, 78 patients (45%) were found to be HIV Ab-positive. As of March, 1988, of the seropositive patients, 63 (80.8%) had an asymptomatic HIV infection (Group II/CDC), three (3.8%) had a persistent generalized lymphadenopathy (Group III/CDC). The 12 (15.4%) remaining patients could be classified in Group IV of the CDC classification due to their symptoms and signs; in particular, 10 came under surveillance case definition for AIDS. Assay for the HIV antigen was positive in 14 (17.9%) seropositive hemophiliacs. With regard to the immunological features, our data clearly show that a sharp decline in the number of CD4+ cells was associated with symptomatic forms of the disease. An evaluation of the time elapsed from seroconversion to the appearance of the symptomatic clinical condition showed an average incubation of 37 months.

The aim of the present work was to develop an in vitro model of eosinophil cytotoxicity which mimics numerous in vivo situations characterized by complement activation through the alternative pathway. Our results demonstrate that eosinophilic granulocytes from patients with parasitic diseases and blood eosinophilia were able to damage chicken red blood cells when incubated with zymosan-activated serum (ZAS) as assessed by a 51Cr release assay. The phenomenon was independent of the presence of antibodies directed against the target cells and related to the quantity of ZAS added to the wells. As target cell lysis is totally or partially inhibited by catalase, sodium azide and potassium cyanide, an involvement of toxic oxygen derivatives as cytolytic mediators was suggested.

Antibody responses were estimated in 42 healthy high risk volunteers submitted to three monthly intradeltoid inoculations of a 5 micrograms HBs vaccine containing both subtypes adw and ayw. The presence and concentration of anti-HBs varied according to individual responses and the number of injections. One month after the 1st dose those responding numbered 19%, one month after the 2nd the number rose to 83,3%, and reached 100% one month after the 3rd dose. In a few cases antibody levels were low (less than or equal to 50 mIU/ml), while in most subjects they rose after the 2nd dose, reaching high titres. Concordance and comparability of anti-HBs concentration were achieved by three different measurements (S/N, RIA Units, mIU/ml). No important side effects were observed. The timing of booster doses is discussed.

The antigenemia and the patterns of antibodies to core protein (p24) and envelope glycoproteins (gp41, gp120) have been investigated in 81 patients with Human Immunodeficiency Virus (HIV) infection followed prospectively for 24 months. HIV antigen was detectable in 23 (28.4%) patients at entry to the study (13/13 with AIDS and 10/23 with ARC) and in 33 (40.7%) at the end (25/28 with AIDS, 5/12 with ARC e 3/14 with LAS). Anti-p24 were positive in 51 (63.0%) patients at the entry (26/30 symptomless, 13/15 with LAS e 12/23 with ARC) and in 41 (50.6%) at the end of the study (23/27 symptomless, 9/14 with LAS, 7/12 with ARC e 2/28 with AIDS). All patients were positive for anti-gp41 and showed no significant changes in the antibody titers during the two years of follow-up; by contrast, anti-gp120 was undetectable in most patients (26/28) with AIDS. Clinical progression in a high proportion of patients was associated with the appearance of HIV antigen, with the decline of anti-p24 titers and with no antibody reactivity to gp120 glycoprotein.

A brief account of the aims sought by multiple antibiotic management is followed by an assessment of the antagonism and synergism displayed by associations of two bactericidal antibiotics, two bacteriostatic antibiotics, and one bactericidal and one bacteriostatic antibiotic. Instances of synergism between bactericides (particularly penicillins and aminosides) are mentioned. Stress is laid on recent studies on the mechanism of action of antibacterial drugs showing unmistakeable synergism between trimethoprim and sulphamethoxazol and between chloramphenicol and tetracycline. The antagonism between bactericides and bacteriostatics noted by Jawetz et Al. has not been confirmed clinically in a number of reported series. The main indications for combined antiobiotic therapy are reviewed: endocarditis, purulent meningitis, staphylococcia, brucellosis, salmonellosis, shigellosis, other Gram-negative infections and fever in the course of blood diseases. References is made to personal experience in the management of 35 cases of bacterial endocarditis, 15 cases of purulent meningitis and various forms of serious Gram-negative infection. Leaving aside exceptional cases, the clinical effects of antibiotic associations are uncertain and influenced by too many variables. The technique is still of importance, however, despite the introduction of many new antibiotics. It must not be thought of as a handy method for indiscriminate use, however; its indications (which are summarised) are quite clear.

A new procedure, based on centrifugation through multiple discontinuous gradients of polyvinylpyrrolidone-coated silica particles has been developed for the separation of almost pure eosinophils from blood samples of healthy donors. When this technique is employed for the purification of eosinophils from the peripheral blood of patients with parasitic diseases, two cell fractions almost pure in eosinophil granulocytes are harvested at different densities. Preliminary results, concerning the characterization of these cell fractions, indicate that in the terms of detectable membrane receptors and K cell activity, two distinct eosinophil subpopulations can be recognized.

The aim of this review is to examine some of the most important findings pointing toward human eosinophil heterogeneity. Special importance is given to cell density, surface receptors, metabolism and response to biological products or synthetic compounds.

The quantitative assay of serum IgE was performed in 34 patients with active hepatic and extrahepatic hydatidosis, in 10 subjects with previous hydatidosis, who underwent surgery during the preceding 8 years, without clinical signs of relapse, and in 15 normal bloods donors. To this purpose a new type of plate from the market was employed, which, adopting radial immunodiffusion, allows determining quantitatively the IgE serum values at the upper normal limits (800 I.U./ml) besides higher levels. IgE serum concentrations, higher than 800 I.U./ml, were detected in 33 (97.06%) out of the 34 patients with active hydatidosis, in 5 (50%) out of the 10 subjects with previous hydatidosis, in 4 (26.67%) out of the 15 normal subjects. The statistical analysis of the results showed the significance of the comparison between the IgE values observed among the group of the patients with active hydatidosis and those, respectively, of the subjects with previous hydatidosis (p less than 0.05) and of the normal subjects (p less than 0.001). The results obtained are discussed in the light of the most recent knowledge on the role played by IgE in the complex immune mechanism of parasitic diseases.

Patients with chronic uremia undergoing periodic haemodialysis were found to have low levels of vitamin B6 (12 out of 18 patients). The same subjects also showed a reduction of the immunocompetence. The AA. report that the administration of pyridoxine (100 mg/die for 4 weeks) can induce a normalization of the vitamin levels and of some immunological parameters.

A microplate method of enzyme-linked immunosorbent assay (ELISA) was adapted for the demonstration of antibodies to influenza A and B in 25 paired acute and convalescent sera taken from patients with influenza A infection, in 11 single convalescent sera collected from patients with acute respiratory infection and serological evidence of influenza B infection, in 14 paired sera collected from volunteers who were vaccinated with an aqueous inactivated influenza A and B vaccine, and in 15 serum samples from normal subjects. Comparison showed that ELISA was more sensitive than the hemagglutination-inhibition test. The enzyme-immunoassay gave equally reliable and reproducible results and requires very small amounts of antigen and sera. This simple test may be suitable for use in large seroepidemiological surveys.

The radioallergosorbent test (RAST) for specific IgE antibodies to Echinococcus granulosus was compared with other immunological methods in regard to sensitivity, specificity and its use as a diagnostic aid for hydatid disease. Sera used were from patients with active hydatidosis proved surgically, from persons operated for hydatidosis during the previous 2-10 years and from patients with other parasitic diseases or healthy subjects. Results with enzyme-immuno assay (ELISA), indirect haemagglutination (IHA), counter-immunoelectrophoresis (CIEP) and skin test were compared with those with RAST. The percentage of positive RAST reactions (81.2%) among the patients with active hydatidosis was slightly lower than the percentage of positive ELISA (90.6%), IHA (90.6%) and skin test (87.5%) and was superior to CIEP (75%). Among the patients with previous hydatidosis, the RAST was negative in 90% of case, whereas other serological tests were positive in a considerable proportion of cases (ELISA test, 80%; IHA test, 40%; CIEP test, 40%; skin test, 60%). A high percentage (50%) of false positive RAST reactions have been observed in sera from patients infested with other parasites. Results indicated that the RAST for IgE antibodies not be used as the only method for diagnosis of hydatidosis, but it may be employed, if serological data obtained before surgery are available for comparison, for evaluate the results of surgery and to clarify the prognosis.

Twenty-four episodes of bacterial infections were identified over a 18 month period in 11 patients (8 with acquired immunodeficiency syndrome and 3 with AIDS related complex). Eight of the 11 infected patients were drug abusers and 3 homosexual people. Nosocomial bacterial infections were common in patients with AIDS and had high fatality rates. Gram-negative bacteria resulted the most common micro-organisms (E.coli, Proteus, Enterobacter, Serratia, Klebsiella). The Aztreonam treatment was very useful in providing bacteria eradication. Gram-positive bacteria as Staphylococcus from a sepsis and Enterococcus from a cystopyelitis were eradicated by B-lactam antibiotics. Common micro-organism are frequent in patients affected by LAS/ARC or AIDS and they negatively interfere with the disease outcome.

Eosinophilic granulocytes from the blood of patients with parasitic diseases were preincubated in the presence or absence of beta-interferon (beta-IFN). The number of cells bearing IgG-Fc receptors was determined by rosette formation with chicken erythrocytes coated with IgG antibodies. beta-IFN augmented the expression of IgG-Fc receptors on the cells within 1 h incubation. Treatment of beta-IFN with heat or acid did not abolish the activity. The doses of beta-IFN needed to induce the modulations of IgG-Fc receptors could also augment the eosinophil-mediated antibody-dependent cytotoxicity (ADCC) against chicken red blood cells which resulted most pronounced when the IgG antibodies were present in suboptimal amount. These data suggest the role of beta-IFN in the host resistance to parasitic diseases, mainly in the initial phases of parasitic infestation when the specific IgG antibody levels are very low.

An evaluation of the E.L.I.S.A. method, compared to the indirect hemagglutination (I.H.) and to the counterimmunoelectrophoresis (CIEP) tests for the biological diagnosis of hydatidosis, was performed on 31 sera of patients, carrier of hydatid cysts, on 17 sera of patients with other infectious and parasitic diseases, and on 7 sera of blood donors. The immunoenzymatic test turned out positive in 30 out of the 31 sera of the patients with active hydatidosis (96.7%), while IH and CIEP turned out positive in 29 cases (93.5%). The control sera from patients with other diseases proved to be all negative, except one from a patient with active schistosomiasis. E.L.I.S.A. test was constantly negative with the sera of normal subjects. The validity and usefulness of E.L.I.S.A test for the diagnosis of the hydatid disease is discussed.

The presence of hepatitis B virus (HBV) and human immunodeficiency virus (HIV) was investigated using hybridization in 15 lymph nodes and one Kaposi's sarcoma skin lesion obtained from HIV-positive patients. Cryostat tissue sections were hybridized with chemically modified DNA probes for HBV and HIV. HIV genome was mainly observed in the cytoplasm of cells present in 7/15 lymph nodes and in the Kaposi's sarcoma skin lesion, thus indicating the expression of HIV replication. Control samples hybridized with an HTLV I probe were negative. HBV genome was found in the cytoplasm of lymphoid mononuclear cells in 2/7 lymph nodes, obtained from HIV+ patients without serum markers of ongoing HBV infection. Lymph node positivity for HBV DNA also confirms that lymphoid cells may be a target for HBV. Since HBV infection seems to precede HIV infection in nearly all patients, it is possible that it may represent a factor facilitating the development of the HIV-related disease.