Biomedical subjects

E Rosati

Publications and source records attributed to E Rosati.

30 records · Page 2Linked to original sources

PubMed1992

In vivo modulation of lymphokine-activated killer cell activity by cell wall components of Candida albicans.

We have previously reported that inoculating CD2F1 mice intraperitoneally with five doses of 2 x 10(7) inactivated Candida albicans (CA) cells was associated with the induction of lymphokine-activated killer (LAK)-like effectors. In this study we investigated the ability of some purified cell wall components of CA (CA-CW) to induce LAK-like cells in vivo. Multiple administrations of glucan ghost (GG), a mannoprotein mixture (MP) and a low-protein mannan fraction (M) at variance with whole CA did not induce LAK-like cells in the peritoneal cavity. However, the broad-spectrum antitumor cytotoxicity induced by CA could be recalled to a high level by a booster dose of MP and M, but not GG, given up to 70 days after the multiple CA-treatment. This induced cytotoxicity was maximum when the booster was given on Day +14 after CA-treatment and minimum on Day +70. In CA-treated mice, inoculated on Day +30 with CA or MP, LAK-like cytotoxicity was already significantly increased 4 hr after the booster, but the maximum value was reached at 24 hr. Anti-mannan antibodies did not interfere with LAK-like cells induction by CA because splenectomy before CA-treatment or passive administration of anti-mannan antibodies had no effect on the rapid activation of cytotoxicity by CA or a booster dose of MP. Administration of recombinant human interleukin-2 (rhIL-2) to CA-treated mice induced a higher level of NK activity than that induced by the same dose in untreated control mice, but did not activate LAK-like effectors. The results indicate that LAK-like effectors are easily generated in the peritoneal cavity by a booster with a defined antigenic constituent of CA cell wall for a long period in CA-sensitized mice.

Animals↗

PubMed1991

In-vitro effects of teicoplanin, teicoplanin derivative MDL 62211 and vancomycin on human polymorphonuclear cell function.

The in-vitro effects on human neutrophil (PMN) functions of three structurally related glycopeptide antibiotics, vancomycin, teicoplanin and the teicoplanin derivative MDL 62211 were investigated. Teicoplanin and MDL 62211 significantly inhibited adherence, chemotaxis, phagocytosis and killing of Candida albicans by PMN's at a concentration of 500 mg/l, whereas PMN viability was only affected at drug concentrations of 2000 mg/l. Vancomycin interfered with PMN adherence and phagocytosis only at a concentration of 2000 mg/l without affecting PMN viability. Chemotaxis and killing of C. albicans were also not affected by this concentration. Teicoplanin and the teicoplanin-derivative MDL 62211 was found to have adverse effects on selected indices of PMN function in vitro only at concentrations higher than those employed in therapy, while vancomycin interfered only at very high concentrations.

Anti-Bacterial Agents↗

PubMed1991

Fungicidal activity of Candida albicans-induced murine lymphokine-activated killer cells against C. albicans hyphae in vitro.

Multiple intraperitoneal injections of inactivated Candida albicans cells resulted in the generation of cytotoxic peritoneal cells with phenotypical and functional properties similar to in vitro-generated lymphokine-activated killer (LAK) cells. Using an in vitro [3H]glucose uptake assay, C. albicans-induced LAK-like (CA-LAK) cells exhibited high levels of anti-hyphal activity, the effects being effector to target cell (E:T) ratio- and time-dependent. Maximal levels of anti-C. albicans activity (approximately 60%) were observed after 4 h and at E:T greater than or equal to 300:1. Similar patterns of anti-C. albicans activity were exerted by in vivo-activated natural killer (NK) cells, in vitro interleukin-2- (IL-2) generated LAK cells and polymorphonuclear cells. The anti-hyphal activity of CA-LAK cells was enriched by separation on a Percoll gradient, F2 and F3 fractions retaining most of the activity. Experiments using immunodepressed animals demonstrated that the in vivo lethality of the C. albicans hyphal form is significantly affected by in vitro pre-exposure to CA-LAK cells. While control mice receiving C. albicans alone had a median survival time of 2 d, mice receiving C. albicans pre-exposed to CA-LAK cells (E:T = 300:1) had a median survival time of 15 d. Overall, the susceptibility of the C. albicans hyphal form to CA-LAK cells suggests that C. albicans-induced effectors might play a significant role as a second-line defence mechanism against the C. albicans hyphal form.

Animals↗

PubMed1990

Induction of LAK-like cells in the peritoneal cavity of mice by inactivated Candida albicans.

We have investigated the effect of multiple administrations of inactivated Candida albicans (CA) cells on induction of non-MHC-restricted antitumor cytotoxic responses both in normal and congenitally athymic (nude) mice. Intraperitoneal inoculation of CD2F1 mice with five doses of 2 x 10(7) CA cells over a 2-week interval was associated with the induction of peritoneal exudate cells (PEC) that mediated natural killer cell activity. These cells, in contrast to those elicited by a single dose of CA, killed both NK-sensitive and NK-resistant tumor target cells in vitro. This broad-spectrum, antitumor cytotoxicity peaked 1 day after the last injection of CA, and decreased to control values within 6 (NK-resistant) or 14 (NK-sensitive target cells) days. Cytotoxicity could be recalled to a high level by a boosting injection of CA or a major mannoprotein-soluble antigen (MP) from the Candida cell wall, given 30 days after multiple CA treatment. Upon a 24-hr in vitro incubation, CA-induced peritoneal immunoeffectors lost their killing activity unless human recombinant interleukin-2 (rIL-2) was added to cultures. The non-MHC-restricted cytotoxic PEC activity induced by CA was mainly associated with nonadherent, nonphagocytic large granular lymphocytes (LGL) which exhibited the following phenotypes: (i) asialo GM1+, Lyt 2.2-, and partially Thy 1.2+ (effectors active against NK-sensitive targets) and (ii) asialo GM1+, Lyt 2.2-, and Thy 1.2+ (effectors active against NK-resistant targets). Nude mice also responded to multiple CA inoculations by displaying high cytotoxic activity against NK-sensitive targets and significant cytotoxicity against NK-resistant targets. This cytotoxicity could be recalled on Day +30, and the cytotoxic effectors involved were highly sensitive to anti-asialo GM1 plus complement treatment. Overall, the results add further experimental evidence to the wide range of immunomodulatory properties possessed by C. albicans, and demonstrate that the majority of antitumor cytotoxic activity induced by fungal cells was due to lymphokine-activated killer (LAK)-like effectors.

Animals↗

PubMed1990

Experimental model of type IV Streptococcus agalactiae (group B streptococcus) infection in mice with early development of septic arthritis.

We have established an experimental murine model to gain insight into the pathogenicity and clinical features of type IV group B streptococcus (GBS) infections. Adult CD-1 mice were challenged intravenously with 10(7) type IV GBS cells, inducing systemic invasion. Most of the animals were able to clear the infection from the blood, brain, and lungs within 2 weeks and from the spleen and liver within 1 month. However, the animals were unable to clear the microorganism from the joints and kidneys during the 60-day observation period. About 80% of the mice challenged intravenously with type IV GBS manifested early septic arthritis, which evolved from an acute exudative synovitis to permanent lesions characterized by irreversible joint damage and ankylosis. Induction of persistent septic arthritis was dependent on the number and viability of microorganisms inoculated and was unrelated to the strain of type IV GBS and the growth phase of the inoculum. Type-specific antibodies of both immunoglobulin M and G classes could be detected by agglutination and enzyme-linked immunosorbent assay from days 7 and 14, respectively; immunoglobulin G antibodies persisted for more than 40 days. Complexes of antibodies and group- and type-specific antigens were detected in mouse sera 24 h after infection and persisted up to day 22. These results were obtained an experimental model of type IV GBS chronic infection with early development of septic arthritis, which could be useful in future studies of pathogenicity and immune mechanisms involved in the host resistance to this microorganism.

Animals↗

PubMed1990

[The role of episacroiliac lipomas as a cause of pseudolumbago-sciatica syndromes].

With their research, the authors intend to recall the existence of episacroiliac lipomas. These growths are important in as much as they cause low lumbar pain where the objective and instrumental signs typical of radicular lumbar syndromes are not present. Amongst other routine instrumental tests the echo scan is suggested for a more precise record. A simple operation relieves pain once and for all.

Adult↗

PubMed1989

[Neonatal hyperthyroidism with early onset and protracted course].

Neonatal hyperthyroidism has often been described as a rare, transient disorder in which the mother has hyperthyroidism during her pregnancy. We have found 99 cases mentioned in recent literature, but not in all reports the clinical characteristics were described. This survey has shown that the prolonged clinical course, though less common than the transient one, is to be taken into account. A case of a female child who had signs of hyperthyroidism soon after the birth is presented. Now, at the age of 7.8 years, she continues to have hyperthyroidism with several problems in treatment.

Child↗

PubMed1989

[Methodologic approach to the therapeutic problem of infant and childhood obesity. Review of the literature and personal experience].

Notwithstanding the high prevalence and morbidity, current knowledge of obesity is rather rudimentary. Nevertheless recent findings have enabled us to surmount anachronistic nosographic generalizations whereby excess weight was attributed only to inappropriate and excessive food intake and the lack of physical exercise. Various studies indicate that there are complex interactions in determining weight excess: genetic, psychosocial, cultural but also biochemical factors are incriminated and it is now recognised that the aetiology of obesity is multifactorial and that, consequently, there are different types of obesity. However, in most studies concerning the therapeutic approach, it is noted that the same type of treatment is applied to groups of subjects that are probably highly heterogeneous for type of obesity. No easy or final solution to the problem is proposed as for the moment no ideal treatment exists. What is suggested is the need to attempt to identify possible factors linked to weight excess before commencing the therapeutic approach. For each single case, this could permit the use of the most appropriate treatment and make therapeutic results less frustrating.

Adolescent↗

PubMed1987

The role of the tibiofibular interosseous membrane in the repair of fractures of the tibia and fibula.

Anatomical studies were carried out to explore the relationship between the tibiofibular interosseous membrane and the long bones of the leg. Based on the data obtained from experimental fractures it appears that the interosseous membrane, which forms the so-called osteoperiosteal pocket, plays an important role in the repair of leg fractures. Further studies are being undertaken to validate this hypothesis and arrive at a more accurate interpretation of the phenomena observed.

Bony Callus↗

PubMedDate not supplied

In vitro effects of meropenem and imipenem/cilastatin on some functions of human natural effector cells.

Meropenem, a new carbapenem antibiotic, was assessed to evaluate its effects on some functional parameters of human polymorphonuclear (PMN) and natural killer (NK) cells in comparison with imipenem/cilastatin. Both drugs significantly inhibited PMN phagocytosis and chemotaxis at concentrations of 2,000 and 4,000 microg/ml. They affected PMN microbicidal activity, evaluated against Candida albicans, only at 4,000 microg/ml. A study of the effects of both drugs on peripheral NK populations and the human NK line (NK-92) showed that even at 4,000 microg/ml there was no effect on antitumor activity. These data indicate that meropenem can reduce some PMN antimicrobial functions only at very high concentrations like imipenem/cilastatin, whereas no concentration influenced NK activity.

Candida↗

PubMedDate not supplied

Scintigraphic evaluation of gastroesophageal reflux in newborns.

OBJECTIVES: This study was carried out to verify whether during neonatal stage gastroesophageal scintigraphy, may be useful not only to diagnose gastroesophageal reflux (GER), but also to detect pulmonary aspiration, at times responsible for respiratory symptoms frequently associated with GER. PATIENTS AND METHODS: Gastroesophageal scintigraphy was performed on 50 newborns admitted to NICU of Brindisi in the last two years who presented symptoms as cyanosis, apnoea, bradycardia, laringeal stridor, wheezing, not related to respiratory or cardiac problems, but suspected to be clinical suggestive symptoms of "pathological" GER. After administration of 99mTC mixed with the usual meal formula, we obtained a recording period of 60-90 minutes and a later recording at 4 and 24 hours to document radioactive material in lungs. RESULTS: Scintigraphy showed GER in 40/50 cases and despite frequent observation of respiratory symptoms (39/40 cases) in these newborns never radiation in pulmonary fields. CONCLUSIONS: Our results could indicate that scintigraphy, noninvasive and low in radiation, may be considered effective and reliable to diagnose GER in newborns. The absence of radiation in pulmonary fields could indicate that respiratory symptoms frequently associated with GER could depend on involuntary mechanism of vagal type and not on pulmonary aspiration.

Bradycardia↗

PubMedDate not supplied

[Effects of recombinant human erythropoietin in the treatment of anemia of prematurity].

13 premature babies (gestational age 31.1 +/- 0.9 weeks and birth weight 1586 +/- 261 g) were randomly assigned to receive recombinant human erythropoietin (200 U/kg i.v. three times a week during 4 weeks) or no (13 babies) as soon as haematocrit decrease < 30% between second and seventh week (TO). The two groups had similar gestational age, birth weight, Apgar score 1' and 5', O2-therapy, IPPV and volume of packed erythrocytes transfused before TO. Treatment was started at 30 +/- 0.5 days (range 21-42). At TO all subjects had not cardiopulmonary compromission, sepsis, O2-dependence, GMH-IVH > or = 2 degree grade and received iron and Vit. E by i.m. Result were evaluated through determination of hemoglobin, haematocrit, reticulocytes and volume of packed erythrocytes before and on days 7, 14, 21 and 28 of therapy. After rHuEPO the number of reticulocytes increased on days 21 and 28 of therapy (on day 21: 92.4 +/- 34.2 x 1000/L vs. 71.8 +/- 21.0, p < 0.10; on day 28: 116.2 +/- 42.9 vs. 83.8 +/- 23.2, p < 0.05); otherwise the number of transfusion (0.2 +/- 0.4 vs. 1.0 +/- 1.2, p < 0.10) and volume of packed erythrocytes (3.0 +/- 6.3 ml/kg vs. 14.9 +/- 15.9, p < 0.05) were reduced. Serum erythropoietin levels did not change during treatment, probably because, reducing the lowering of hemoglobin, hypoxic stimulus to increase of erythropoietin was suppressed.

Anemia, Neonatal↗