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M Russo

Publications and source records attributed to M Russo.

At least 91 records · Page 5Linked to original sources
PubMed1997

A new murine model of pulmonary eosinophilic hypersensitivity: contribution to experimental asthma.

BACKGROUND: We have recently described a model of hypersensitivity reaction in the mouse paw, which induces a typical late-phase reaction with a marked eosinophilic infiltrate. OBJECTIVE: In the search for a murine model of asthma, this model was adapted to the lungs and compared with other models of pulmonary hypersensitivity. METHODS: A fragment of heat-coagulated hen's egg white was implanted subcutaneously, and 14 days later, the mice were challenged intratracheally with aggregated ovalbumin. Comparison was made with a group that received subcutaneous injection of soluble ovalbumin in alumen, challenged as described above and with four additional protocols of immunization and challenge. RESULTS: Forty-eight hours after challenge, the percentage of eosinophils was higher in the egg white implant group (35%) than in the group immunized with ovalbumin in alumen (10.4%). The eosinophil peroxidase activity in lung homogenates of the first group was also significantly higher (529 ng/ml) than that of the second group (43 ng/ml). These results were reproduced in five different mouse strains. Compared with five different models of lung hypersensitivity, the egg white implant model was unique in terms of persistence of the pulmonary eosinophilia. Histopathologic analysis of the lungs of mice immunized with egg white implant showed peribronchial, perivascular, and intraepithelial eosinophil infiltration; morphologic characteristics of bronchoconstriction; and patchy epithelial shedding. At 21 days, in addition to persistence of eosinophil infiltrate, enlarged alveoli, reflecting air trapping, were observed. CONCLUSION: On the basis of the characteristics of the model described here, we propose it as a suitable murine model of asthma.

Administration, Cutaneous↗
PubMed1997

PAF modulates eicosanoids and TNF release in immune-complex arthritis in rats.

The participation of lipid mediators and tumor necrosis factor (TNF) on an experimental model of immune-complex arthritis was investigated. Male Wistar rats received intraarticular injection of rabbit antibodies to bovine serum albumin into the knee joint followed by i.v. injection of the antigen. The levels of eicosanoids and TNF released into the synovial exudates were then assessed using ELISA and the L929 lytic cell assay, respectively. Increase in the levels of LTB4, TXB2 and PGE2 were detected 5 min, 5 min, and 6 h after arthritis induction, respectively. Pretreatment with the PAF receptor antagonist WEB 2170 decreased the levels of PGE2 and increased those of LTB4, without altering TXB2 levels. Increase in the levels of TNF was detected at 3 h of arthritis. Pretreatment with either the cycloxygenase inhibitor indomethacin or the 5-lipoxygenase inhibitor L-663,536 had no effect on TNF levels. Pretreatment with WEB 2170 significantly decreased TNF levels. These results are the first demonstration of eicosanoids and TNF release in immune-complex arthritis. The data also suggest that PAF had both a positive and negative modulatory role on the release of PGE2 and LTB4, respectively. Moreover, TNF release into the synovial exudate did not depend on eicosanoids whereas platelet activating factor (PAF) appeared to mediate the release of this cytokine in the model.

Animals↗
PubMed1997

Molecular analysis of the pothos latent virus genome.

Pothos latent virus (PoLV) is an isometric virus with a positive-sense, single-stranded RNA genome of 4415 nt. The genome contains five open reading frames (ORF), coding for five proteins with approximate molecular masses of 25, 84, 40, 27 and 14 kDa, respectively. In vitro synthesized PoLV RNA was infectious to Nicotiana benthamiana plants and protoplasts, but could not support replication of the defective interfering (DI) and satellite RNAs associated with Cymbidium ringspot tombusvirus. No DI RNA related to PoLV was generated after repeated passaging with infected sap. Mutagenesis studies defined the role of the ORF 4 product (27 kDa) as a movement protein, and the ORF 5 product (14 kDa) as being responsible for symptom severity. Moreover, it was shown that the coat protein (CP) is important in regulating synthesis of the 14 kDa protein, excess production of which is lethal to infected plants. CP mutants defective in capsid formation infected plants systemically and induced severe necrotic symptoms. Conversely, CP mutants able to form apparently normal virus particles induced symptoms indistinguishable from those elicited by wild-type virus.

Amino Acid Sequence↗
PubMed1997

A new murine model of persistent lung eosinophilic inflammation.

We summarize here the main characteristics of a novel model of pulmonary hypersensitivity. Mice were immunized with a subcutaneous implant of a fragment of heat solidified chicken egg white and 14 days later challenged with ovalbumin given either by aerosol or by intratracheal instillation. This procedure induces a persistent eosinophilic lung inflammation, a marked bone marrow eosinophilia, and Th2-type isotypic profile with histopathological findings that resemble human asthma. Further, this model is simple to perform, reproducible in different strains of mice, does not require adjuvants nor multiple boosters. Based on these characteristics we propose it as a suitable murine model of allergic eosinophilic lung inflammation.

Animals↗
PubMed1997

[The choice of antibiotic therapy for bacterial infections in patients with cirrhosis of the liver].

Patients with liver cirrhosis have an impaired function of reticuloendothelial system; moreover they exhibit several defects of cellular and humoral immunity. These deficiencies enhance their susceptibility to bacterial infections. The prognosis is better if the infection is detected as early as possible and treated adequately. Except in cases of septicemia, empirical monotherapy is effective. Broad-spectrum beta-lactam antibiotics have proved efficient for the treatment of severe infections; a limitation of third-generation cephalosporins is their ineffectiveness against Enterococci; the acylureidopenicillins may be a good choice since they are active against Enterococci and most enteric, pulmonary and urinary pathogens, including Escherichia coli and Streptococcus pneumoniae which are the pathogens most frequently isolated from cirrhotic patients with severe infection. Similarly, the combination of a beta-lactamase inhibitor with a penicillin may offer an adequate antibacterial spectrum. Piperacillin, like other beta-lactam antibiotics, can induce leukopenia in patients with cirrhosis; the more severe the hepatic dysfunction, the greater the risk; a reduction in dosages is necessary. Meropenem monotherapy is effective and safe for the initial therapeutic regimen of bacterial infection. The fluoroquinolones may be useful for the treatment of infections in liver cirrhosis; however, the marginal activity against S. pneumoniae is a drawback. Oral long-term fluoroquinolone administration is utilized for the prevention of spontaneous bacterial peritonitis recurrence; selective intestinal decontamination with fluoroquinolones is useful in preventing bacterial infections in cirrhosis with gastrointestinal hemorrhage. Given the high risk of nephrotoxicity due to aminoglycosides in liver cirrhosis, these antibiotics should be used only in cases of severe infection with septicemia, in which beta-lactam-aminoglycoside combination is indicated for rapid bactericidal effect and enhanced killing afforded by synergism. Perhaps a short course (no more than 3 days) and a once-daily schedule of administration would minimize the risk of aminoglycoside-induced nephrotoxicity.

English Abstract↗
PubMed1997

Myocardial dysplasia in a 3rd-trimester fetus. An ultrasound and pathologic study.

Arrested myocardial development, often described as spongiosum heart, has been reported in association with obstructive semilunar valve disease and, much more rarely, as a primary disease in adolescents and adults. To our knowledge, this condition has never been diagnosed in utero. We describe the echocardiographic and pathoanatomic findings of the 1st case of myocardial dysplasia detected in utero by ultrasound. A 28-year-old woman, gravida 2, para 1, was referred to our unit at 34 weeks of gestation due to severe fetal hydrops. On echocardiography, we observed gross fetal cardiomegaly (particularly of the septal and ventricular myocardium), an unusually bright myocardial echostructure, thick trabeculations in both ventricular chambers, and severe loss of myocardial contraction. There were normal ventriculoarterial connections and no signs of obstructive semilunar valve disease. After fetal death, necropsy confirmed the presence of spongiosum heart and the diagnosis of myocardial dysplasia--which term best describes this disorder in its various temporal expressions. Because this condition has never before been observed prenatally, no consideration has been given to intrauterine management. We recommend that fetal cardiac function be monitored echocardiographically whenever a pregnant patient has a positive family history of this disease. There is a possibility that the life of the affected fetus might be prolonged beyond the gestational period by avoiding intrauterine cardiac decompensation, through early delivery. We recommend further that the parents of these children be advised of the risks associated with future pregnancies. Little is known about the pattern of inheritance of myocardial dysplasia, but the disorder appears to be familial. Therefore, the possibility that it may recur within the same generation must be taken into account.

Adult↗
PubMed1996

Heller syndrome in a pre-school boy. Proposed medical evaluation and hypothesized pathogenesis.

The case of a 6-year-old boy who developed childhood disintegrative disorder (Heller syndrome) at the age of 4 years is presented, and specifics of the neurologic evaluation are detailed. A table is provided suggesting the complete neurologic work-up with the potential findings for children presenting with signs and symptoms of deterioration. A hypothesis for the aetiology of Heller syndrome proposes that predisposing genetic factors when combined with an environmental stress result in the deposition of amyloid and the disruption of synaptic transmission during the deterioration period. Speculation that the deterioration may be self-limited by activation of an immune response is based upon earlier findings that interleukin 1 has been shown to be involved in the breakdown of amyloid precursor protein in humans.

Child↗
PubMed1996

Characterization, nucleotide sequence and genome organization of leek white stripe virus, a putative new species of the genus Necrovirus.

White stripe is a disease affecting leek in France with which an isometric virus c. 30 nm in diameter is associated. The most evident symptom is the presence of white stripes on the leaves extending to the stem. Attempts to demonstrate transmission through the soil by sowing or transplanting leek in contaminated soil were unsuccessful. The virus was transmitted by sap inoculation to a narrow range of herbaceous hosts, all of which were infected only locally. Virus purification was from infected leek tissues, where it accumulated in large amounts, as demonstrated by ultrastructural observations. RNA was extracted from purified virus preparations and cDNA clones were prepared. The complete nucleotide sequence of the viral RNA was determined: The genome is 3,662 nucleotides long and contains five open reading frames (ORFs). The first (ORF 1) encodes a putative translation product of M(r) 23,803 (p24) and read through of its amber stop codon results in a protein of M(r) 82,625 (p83) (ORF 2). ORF 3 and ORF 4 encode two small polypeptides of M(r) 11,280 (p11) and M(r) 6,261 (p6), respectively. ORF 5 encodes the capsid protein of M(r) 27,460 (p27). The genome organization and sequence alignments with the corresponding products of necroviruses suggest that the virus isolated from leek is a new species in the genus Necrovirus, for which the name of leek white stripe virus (LWSV) is proposed.

Amino Acid Sequence↗
PubMed1996

Hemolytic anemias due to disorders of red cell membrane skeleton.

During the past 10 years, knowledge of the composition, function and supramolecular assembly of the red cell membrane has been greatly expanded by progress in molecular and cell biology. Detailed information on the organization of membrane cytoskeletal proteins and their molecular characterization has allowed us to correlate a number of protein abnormalities with clinical symptoms that are peculiar to hereditary hemolytic anemias (HHA). In particular, three general principles emerge that can help us to understand the pathogenetic mechanisms of HHA: (a) protein-protein and protein-lipid interactions greatly influence the correct assembly of the membrane skeleton; (b) the red blood cell (RBC) membrane skeleton mostly determines the shape (discocyte), deformability (rheologic properties) and durability (half-life and resistence to shear stress) of the erythrocytes; (c) changes in cytoskeletal composition and/or organization can produce alterations in all of the above properties, and therefore they are responsible for the onset of the hemolytic damage.

Anemia, Hemolytic↗
PubMed1996

The influence of T cell subsets on Trypanosoma cruzi multiplication in different organs.

Several studies in mice have strengthened the active role played either by CD4+, CD8+ or both T cell subsets in conferring resistance to Trypanosoma cruzi infection. To date, no studies reported the role played by T cell subsets on parasite multiplication in different organs. In the present work, mice were infected with CL strain of T. cruzi and T cell subset activities were blocked by i.p. injection of monoclonal antibody (mAb) directed against CD4, or IAk, or CD8 molecules. The effect of these treatments was determined by counting the number of parasite nests in heart and liver sections 16 days after infection. Our results showed that mice treated with anti-CD4 or anti-IAk mAbs presented a significant increase in the parasite load in the hearts and in the livers. Conversely, the number of parasites in hearts of anti-CD8 treated mice did not increase significantly. This treatment, however, resulted in a 20-fold increase in the number of parasites found in the liver. Simultaneous depletion of both T cell subsets by treatment of mice with anti-CD4/CD8 mAbs had, in the heart, the same effect as the CD4 depletion. Interestingly, this treatment caused a dramatic increase (200-fold) in the T. cruzi parasitism of the liver. These results indicate that the activity of T cell subsets against T. cruzi varies according to the infected organ.

Animals↗
PubMed1996

[Neonatal cholestatic lithiasis associated with E. coli infection].

BACKGROUND: Cholestasis associated with gallbladder lithiasis is quite uncommon in the neonate. We report such a case possibly due to a bacterial infection. CASE REPORT: A 25 day-old neonate was admitted because he suffered from cholestatic jaundice associated with biological findings of inflammation. Hepatic cellular function and transaminases were normal. Ultrasonography showed hepatomegaly and a 10 mm diameter gallstone with sludge into the gallbladder. The patient was given cefotaxime plus netilmicine. Soluble antigenes for E coli were positive in the urine. Jaundice and inflammatory findings returned to normal within 10 days and ultrasonography was normal at the age of 20 months. CONCLUSION: Neonatal E coli infection could be responsible for gallstone formation since E coli endotoxin may induce biliary stasis and favours lithogenous action of bacterial glycoproteins.

Cholelithiasis↗
PubMed1996

Comparison between outdoor and indoor airborne allergenic activity.

BACKGROUND: Allergenic pollens are usually detected in outdoor air by using volumetric spore traps, which allow measurement of atmospheric concentration as pollen grains per m3 of air. The results of the pollen count are useful primarily for outdoor environments while most people spend most of the day indoors. OBJECTIVE: The purpose of our study was to compare outdoor pollen levels with allergenic activity measured both outdoors and indoors. METHODS: We used a Lanzoni spore trap to measure airborne Urticaceae pollen and filters collecting particles simultaneously indoors and outdoors and assayed each filter for Parietaria judaica allergenic activity. Samples were collected at the Allergological Service of the "A. Cardarelli" Hospital in Naples with the balcony open on some days and closed on others. Allergenic activity (ng/m3) was measured using the immunocapture RAST. RESULTS: With the balcony open there was no great difference between outdoor and indoor allergenic activity, but with the balcony closed there was a reduction of indoor allergenic activity of about one-third in comparison with outdoor allergenic activity. Statistical analysis (Pearson correlation test) indicated a significant correlation between outdoor allergen levels and indoor allergen levels with the balcony open (r = .4415, P < .05), but not with the balcony closed (r = .3160, P > .05); a significant correlation between outdoor pollen count and indoor allergen levels with the balcony open (r = .4809, P < .05), but not with the balcony closed (r = .3858, P > .05); and a highly significant correlation (r = .5225, P < .001) between outdoor pollen count and outdoor allergen levels. CONCLUSIONS: These data provide scientific evidence for the recommendation to hay fever patients to remain indoors during seasons with high levels of outdoor pollens.

Air Pollutants↗
PubMed1996

The 5'-terminal region of a tombusvirus genome determines the origin of multivesicular bodies.

Multivesicular bodies (MVB) are membranous cytoplasmic inclusions that are invariably associated with tombusvirus infections regardless of the virus species, the host, or the tissue examined. MVB are virus-induced structures since they are absent from tissues of healthy plants and are always present both in infected plants and protoplasts. MVB derive from peroxisomes in cells infected by a number of tombusviruses including cymbidium ringspot virus (CymRSV) and from mitochondria in cells infected by another tombusvirus, carnation Italian ringspot virus (CIRV). By using common restriction sites in full-length infectious clones, hybrid clones of these two viruses were constructed. In addition, a mutant of CIRV was prepared in which the protein encoded by the first open reading frame was shortened by 22 amino acids. All mutant transcripts were viable and infected Nicotiana benthamiana plants. Infected leaf tissue samples were collected, processed for thin sectioning, and observed in the electron microscope. The origin of MVB was shown to be under the control of the 5' region of the viral genome. A sequence as short as about 600 nucleotides in ORF 1 contained the determinants for formation of MVB from peroxisomes or mitochondria.

Base Sequence↗
PubMed1996

Measurement of serum levels of eosinophil cationic protein to monitor patients with seasonal respiratory allergy induced by Parietaria pollen (treated and untreated with specific immunotherapy).

This trial studied the behavior of a marker of eosinophilic inflammation, eosinophil cationic protein (ECP), in the peripheral blood of two groups of subjects with seasonal allergic respiratory symptoms (rhinitis and mild bronchial asthma) induced by pollen allergens of Parietaria judaica (P.j.) (one group treated and another untreated with specific immunotherapy [SIT]), to determine what contribution these serial measurements might provide, in comparison with various other tools now available for pollinosis monitoring. In a previously randomized order, we selected 25 patients with monosensitization to P.j. pollen allergens; among them, 12 had started SIT with a P.j. extract in autumn 1993. As a control group, 13 patients were untreated. All patients were studied with various tests at four different times: time I-November 1993; time II-February 1994; time III-end of May 1994; and time IV-September 1994. Blood samples for determination of serum ECP were collected at each time. Methacholine challenge tests were performed at times I and III. A pollen count was also carried out. A statistically significant difference (P < 0.05) was observed in mean ECP levels at times I and III in SIT treated and untreated patients. The interaction between groups and time was not significant. No statistically significant difference was found between PD20 FEV1 values at times I and III in either group. After 1 year of treatment, we did not find any effect of SIT on bronchial hyperresponsiveness or on ECP serum values.

Adult↗
PubMed1996

Allergic skin rash with lamotrigine and concomitant valproate therapy: evidence for an increased risk.

Cutaneous rash is one of the commonest adverse events associated with lamotrigine. We assessed whether the risk is increased in patients receiving concomitant valproate therapy in a population of 103 adult patients with intractable epilepsy, who had lamotrigine added to their treatment. Of the 33 patients taking valproate, 10 (30%) developed a rash, whilst of the 70 not taking valproate, only 6 (8%) developed a rash. This suggests a significantly higher risk of cutaneous rash when starting lamotrigine in patients already taking valproate (p < 0.02).

Adolescent↗
PubMed1996

[Toxoplasmosis in pregnancy: recent acquisitions and new prospects].

Congenital toxoplasmosis may develop after maternal primary infection during pregnancy. The infection is usually asymptomatic in pregnant women but poses a risk of severe effects on the fetus. In Italy the incidence is about 6 per thousand. The infection is transmitted to the fetus in approximately 50 percent of such cases. The risk of transmission rises with growing gestational age at the time of primary infection; on the contrary, the seriousness of the effect on the fetuses becomes less active with more advanced pregnancies. Infants with congenital toxoplasmosis are mostly asymptomatic at birth but long-term studies have indicated that up to 85% of them will develop serious sequelae as severe impairment of vision, mental retardation and deafness during the months or the years after the birth. Preventing congenital toxoplasmosis is fundamental. All seronegative women should be encouraged to observe good dietary and general health regulations until delivery. Today the diagnosis in the mother is more reliable because of the improvements in serological techniques. Moreover, it is possible to identify infected fetuses by prenatal procedures such as ultrasonography, amniocentesis and cordocentesis, of which the last two consent to detect the parasite and/or specific antibodies. Recently a polymerase chain reaction (PCR) assay has been developed for the detection of Toxoplasma in the amniotic fluid. Adequate serological screening of pregnant and prenatal diagnosis can be helpful in reducing the incidence of congenital toxoplasmosis; furthermore abortion should be reserved only to cases with severe toxoplasmosis revealed by ultrasonography. Early recognition of pregnant infection and a specific treatment could reduce the parasitic colonization in the placenta by more than 60% and prevent infection in the fetus. If the fetal infection has already occurred, maternal treatment may modify the fetal disease. Spiramycin as immediate treatment of maternal primary infection is essential in preventing Toxoplasma transmission to the fetus. If the fetus results non-infected, spiramycin should be prolonged until delivery. If the fetus is infected, pyrimethamine-sulphadiazine combination should be given in repeated courses alternated with courses of spiramycin. However, there is an urgent need for more active and safer compounds; it would be useful to evaluate in the pregnant woman other potential therapeutic agents as atovaquone and azithromycin.

English Abstract↗