Effects of rokitamycin on phagocytosis and release of oxidant radicals of human polymorphonuclear leukocytes.

A rational choice of an antimicrobial agent must take into account not only the activity against the specific pathogen but also any possible negative or positive effects on the host defense system. Rokitamycin (RKM) is an orally active 16-membered-ring macrolide; there are no reports of specific investigations of these activities in the literature. Polymorphonuclear neutrophils (PMNs) from healthy adult donors were incubated in medium alone or in medium containing increasing concentrations (1, 10, 50, 100 micrograms/ml) of RKM. In unwashed PMNs phagocytosis was unaffected by RKM, while luminol-amplified chemiluminescence (LACL) was significantly reduced by 50 and 100 micrograms/ml. When PMNs were washed after incubation phagocytosis was not modified but LACL was significantly restored. These characteristics of RKM were similar to those of roxithromycin and can be put in correlation with the cellular/extracellular ratio (30.5 for PMNs and 120 for macrophages) that was similar to that of roxithromycin but higher than of other macrolides. The molecular mechanisms by which high concentrations of these two macrolides produce such an impairment of LACL are still unclear. RKM has no unwanted effects on PMNs because the serum concentrations that can be obtained with the highest doses administered to man are lower than the concentrations which did not affect PMN functions in our study.

HLA typing in chronic type B, D and C hepatitis.

AIMS: We aimed to test the hypothesis that susceptibility to chronic HBV, HDV and HCV infections or their pathology is influenced by host genetic factors. METHODS: The Human Leukocyte Antigens (HLA) (A, B, DR and DQ) were determined by microlymphocytotoxicity assay in patients with chronic C (n = 117), B (n = 97) or D (n = 27) hepatitis and their frequencies were compared with those of 489 healthy controls. RESULTS: No statistically significant association was found between any HLA antigen and chronic B or D hepatitis. A significantly higher frequency of HLA-B14 was observed in patients with chronic persistent or active C hepatitis (16.7% of 90 versus 5.9% of 489, chi(2) = 10.9, pc < 0.05, Relative Risk = 3.17, Etiological Fraction = 0.11). The frequency of HLA-DR5 was lower in HCV positive patients (24.8%) than in controls (45%, chi(2) = 15.1, pc < 0.005, RR = 0.4, EF = -0.37). CONCLUSIONS: No correlation could be observed between clearance of HBV or HDV and HLA phenotype. Immunogenetic factors may have a role in determining susceptibility to chronic HCV hepatitis, and in Italian patients HLA-DR5 is a protective factor.

Influence of brodimoprim on polymorphonuclear leukocyte phagocytosis and oxidant radical production.

Antibiotics not only reach the site of infection, but also penetrate cyclically, during a treatment, into polymorphonuclear leukocytes (PMNs) and may influence their functions positively or negatively. With reference to these aspects, the influence of brodimoprim (BMP), a dimethoxybenzylpyrimidine recently entered into clinical use, on human PMN phagocytosis and oxidant radical production (chemiluminescence) was investigated. PMNs from healthy adult donors were incubated for 50 min in medium alone or in medium containing increasing concentrations (3.7, 7.5, 15, and 30 micrograms/ml) of BMP and trimethoprim (TMP). In unwashed PMNs, phagocytosis was not modified by BMP, but was significantly reduced by 30 micrograms/ml TMP; chemiluminescence was significantly reduced by 15 and 30 micrograms/ml BMP and by all concentrations of TMP. When PMNs were washed after incubation, phagocytosis was unaffected and chemiluminescence was significantly restored. BMP at therapeutic concentrations did not influence PMNs and was less toxic than TMP.

Isolated congenital complete heart block: longterm outcome of mothers, maternal antibody specificity and immunogenetic background.

OBJECTIVE: To assess the longterm outcome of mothers of children with isolated congenital complete heart block (CCHB), and the maternal specific immunoblot pattern and HLA antigens. METHODS: Fifteen mothers of 16 children with isolated CCHB were investigated; their followup extended up to 15.8 years on average after the index delivery. Anti-Ro and La antibodies were detected by counterimmunoelectrophoresis and ELISA; anti-Ro antibodies were studied by immunoblot. HLA typing was done using a microcytotoxicity test. RESULTS: One mother has systemic lupus erythematosus (SLE) before the index delivery. The other mothers developed only minor symptoms (arthralgia, dry eyes and photosensitivity) resembling primary Sjögren's syndrome more than classic lupus. All 15 mothers were anti-Ro and 9 were also anti-La positive, a mean of 12.5 years after the index delivery. Eight mothers reacted with the 52 kDa SSA(Ro) component, and 2 also with the 60 kDa SSA(Ro) component. The prevalence of the DR3 antigen and of the B44/DR5, DR3/DQ2 and A1/Cw7/B8/DR3/DQ2 haplotypes was significantly increased. CONCLUSION: The longterm outcome for the mothers of children with CCHB is more reassuring than generally assumed. All the mothers were anti-Ro positive by sensitive ELISA: Reactivity to the denaturated 52 kDa SSA(Ro) component seems characteristic of these mothers, who presented a particular immunogenetic background.

The activity of a beta subtype of protein kinase C purified from nuclei of human neutrophils is enhanced by treatment with phorbol 12-myristate 13-acetate.

Two protein kinase C isoenzymes were partially purified from the nuclei of human neutrophils, and identified as beta and alpha subtypes. Treatment of neutrophils with phorbol 12-myristate 13-acetate (PMA) caused a 3.8-fold increase of nuclear beta PKC activity, while a minor increase of alpha PKC was observed. This selective activation of beta PKC could help to understand the molecular events involved in phorbol ester-induced cellular modifications.

[Standardization of methods for the preparation of blood components: examination of the operational characteristics of various centrifuges]. / Contribution à la standardisation des méthodes de préparation des hémocomposants: Examen des caracteristiques operationnelles de certaines centrifugeuses.

For a better standardization and comparison of hemocomponents production methods, the A.A. consider the operative characteristics of eight centrifuges used to this purpose in the transfusional centers, according to the method of calculation of the gravities produced during the whole period of centrifugation. The data obtained are used to produce one kind of hemocomponent by several patterns of centrifuges.

Prevalence of some markers of the hepatitis B virus in a blood donor population.

Investigations were made for anti-HBs and anti-HBe antibodies, markers of hepatitis B virus, in a population of HBsAg negative blood donors, but exhibiting high serum transaminase (ALT) values. 25.9% of this population was found to be positive for at least one type of marker antibody. The samples found to be positive only for anti-HBe were examined for anti-HBc antibodies. These donors were re-examined over a period of time until the anti-HBs antibodies disappeared. Further studies will have to be carried out in order to verify whether those samples of blood found to be positive for anti-HBc and/or anti-HBe are really infecting. The advisability of a systematic ALT activity check in all blood donors is stressed.

[Determination of antithrombin III (chromogenic substrates) and FDP in women in treatment with oral estroprogestin agents]. / Valutazione dell'antitrombina III (substrati cromogeni) e FDP in donne in trattamento con estroprogestinici orali.

In 280 women, in fertile age, 133 of whom represented the control group, FDP and antithrombin III with the method of chromogenic substrates were determined. In 147 women, who were taking, for variable period of time, oral estroprogestinic drugs, a significant diminution of antithrombin III was found. No significant differences for FDP were observed.

PIP: 147 women, aged 17-48, on oral contraception (OC) for a period of 3 months-11 years, were observed to study changes in the level of antithrombin 111 and fibrinogenous degradation products (FDP). The patients were compared to 133 controls, who had undergone the same tests. A significant decrease in the concentration of antithrombin 111 was found in most patients, ex especially in those who had been on OCs for a short period of time; the type of contraceptive agent used did not seem to be relevant. No significant differences were found in FDP levels.

[IgA-IgG-IgM serum levels in blood donors. Examination of some variables]. / Livelli sierici delle IgA-IgG-IgM nei donatori di sangue. Esame di alcune variabili

IgA, IgG and IgM serum levels in 603 normal blood donors (510 males and 93 females) have been calculated by the method of single radial immunodiffusion. In every immunoglobulin class the normal values and other important statistical parameters have been determined. Several statistical examinations have been executed to test the influence of some factors as sex, weight, age and number of blood donations on IgA, IgG and IgM serum levels.