Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 51
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Eur J Immunol ; 45(4): 1069-81, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25631937

RESUMO

CD8 T cells contribute to protective immunity against Mycobacterium tuberculosis. In humans, M. tuberculosis reactive CD8 T cells typically recognize peptides associated to classical MHC class Ia molecules, but little information is available on CD8 T cells recognizing M. tuberculosis Ags presented by nonclassical MHC class Ib molecules. We show here that CD8 T cells from tuberculosis (TB) patients recognize HLA-E-binding M. tuberculosis peptides in a CD3/TCR αß mediated and CD8-dependent manner, and represent an additional type of effector cells playing a role in immune response to M. tuberculosis during active infection. HLA-E-restricted recognition of M. tuberculosis peptides is detectable by a significant enhanced ex vivo frequency of tetramer-specific circulating CD8 T cells during active TB. These CD8 T cells produce type 2 cytokines upon antigenic in vitro stimulation, help B cells for Ab production, and mediate limited TRAIL-dependent cytolytic and microbicidal activity toward M. tuberculosis infected target cells. Our results, together with the finding that HLA-E/M. tuberculosis peptide specific CD8 T cells are detected in TB patients with or without HIV coinfection, suggest that this is a new human T-cell population that participates in immune response in TB.


Assuntos
Citocinas/biossíntese , Antígenos de Histocompatibilidade Classe I/imunologia , Mycobacterium tuberculosis/imunologia , Linfócitos T Citotóxicos/imunologia , Tuberculose/imunologia , Adulto , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Células Cultivadas , Coinfecção/imunologia , Coinfecção/microbiologia , Coinfecção/virologia , Citocinas/imunologia , Epitopos de Linfócito T/imunologia , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Subfamília C de Receptores Semelhantes a Lectina de Células NK/imunologia , Subfamília D de Receptores Semelhantes a Lectina de Células NK/imunologia , Ligação Proteica/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Tuberculose/microbiologia , Antígenos HLA-E
2.
Exp Parasitol ; 133(1): 37-43, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23103597

RESUMO

Leishmania parasites are able to undergo apoptosis (programmed cell death), similarly to mammalian cells. Recently it was demonstrated in vitro the anti-leishmanial effect of some natural and synthetic stilbenoids including resveratrol and piceatannol. In this study we evaluated the Leishmanicidal activity of a pool of stilbene derivatives which had previously shown high apoptotic efficacy against neoplastic cells. All the compounds tested were capable to decrease the parasite viability in a dose-dependent manner. Trans-stilbenes proved to be markedly more effective than cis-isomers. This was different from that observed in tumor cells in which cis-stilbenes were more potent cytotoxic agents. Trans-3,4',5-trimethoxy-3'-amino-stilbene (TTAS) was the most active stilbene showing in Leishmania infantum a LD(50) value of 2.6 µg/mL. In contrast TTAS showed a low toxicity when tested on normal hemopoietic cells. This compound induced apoptosis in parasites by disrupting the mitochondrial membrane potential. Moreover it shows the ability to block Leishmania parasites in G(2)-M phase of cell cycle in agreement with the data obtained by affinity chromatography that identify tubulin as the putative target of TTAS. In conclusion, our results indicate that some stilbene derivatives are highly effective as anti-leishmanial agents and TTAS represents a pro-apoptotic agent in Leishmania parasites that merit further in vivo investigation.


Assuntos
Antiprotozoários/farmacologia , Apoptose/efeitos dos fármacos , Leishmania infantum/efeitos dos fármacos , Estilbenos/farmacologia , Anexina A5 , Gluconato de Antimônio e Sódio/farmacologia , Antiprotozoários/química , Antiprotozoários/toxicidade , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Cromatografia de Afinidade , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Citometria de Fluxo , Fase G2/efeitos dos fármacos , Células Progenitoras de Granulócitos e Macrófagos/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Leishmania infantum/citologia , Dose Letal Mediana , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estilbenos/química , Estilbenos/toxicidade , Tubulina (Proteína)/efeitos dos fármacos
3.
New Microbiol ; 35(2): 161-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22707128

RESUMO

Toscana sandfly fever virus (TOSV) is an arthropod-borne virus transmitted to humans by sandfly vectors. It has been associated with human cases of meningitis and meningo-encephalitis mainly occurring during the warm season. We performed a retrospective serological study to evaluate TOSV circulation in Palermo, Sicily, and to compare TOSV seroprevalence in patients with neurological symptoms and in a control group of patients without neurological symptoms. When sera from 155 patients with and without neurological symptoms were evaluated, the rate of overall TOSV IgG reactivity was 17.4%. Patients with neurological symptoms showed a higher percentage of TOSV IgG positivity than control patients (25% versus 10.8%). TOSV exposure was confirmed by virus neutralization tests which also detected a Naples virus (SFNV) infection. TOSV should be considered as an etiologic agent in the differential diagnosis of fever and meningo-encephalitis in Sicily.


Assuntos
Anticorpos Antivirais/imunologia , Doenças do Sistema Nervoso/imunologia , Vírus da Febre do Flebótomo Napolitano/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/epidemiologia , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/virologia , Estudos Retrospectivos , Estudos Soroepidemiológicos , Sicília/epidemiologia
4.
Eur J Immunol ; 40(8): 2211-20, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20540114

RESUMO

Th1 CD4(+) T cells and their derived cytokines are crucial for protection against Mycobacterium tuberculosis. Using multiparametric flow cytometry, we have evaluated the distribution of seven distinct functional states (IFN-γ/IL-2/TNF-α triple expressors, IFN-γ/IL-2, IFN-γ/TNF-α or TNF-α/IL-2 double expressors or IFN-γ, IL-2 or TNF-α single expressors) of CD4(+) T cells in individuals with latent M. tuberculosis infection (LTBI) and active tuberculosis (TB). We found that triple expressors, while detectable in 85-90%TB patients, were only present in 10-15% of LTBI subjects. On the contrary, LTBI subjects had significantly higher (12- to 15-fold) proportions of IL-2/IFN-γ double and IFN-γ single expressors as compared with the other CD4(+) T-cell subsets. Proportions of the other double or single CD4(+) T-cell expressors did not differ between TB and LTBI subjects. These distinct IFN-γ, IL-2 and TNF-α profiles of M. tuberculosis-specific CD4(+) T cells seem to be associated with live bacterial loads, as indicated by the decrease in frequency of multifunctional T cells in TB-infected patients after completion of anti-mycobacterial therapy. Our results suggest that phenotypic and functional signatures of CD4(+) T cells may serve as immunological correlates of protection and curative host responses, and be a useful tool to monitor the efficacy of anti-mycobacterial therapy.


Assuntos
Carga Bacteriana , Linfócitos T CD4-Positivos/metabolismo , Citocinas/metabolismo , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/imunologia , Doença Aguda , Aciltransferases/imunologia , Adulto , Antígenos de Bactérias/imunologia , Carga Bacteriana/imunologia , Proteínas de Bactérias/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/microbiologia , Linfócitos T CD4-Positivos/patologia , Separação Celular , Doença Crônica , Citometria de Fluxo , Humanos , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/patogenicidade , Tuberculose Pulmonar/diagnóstico
5.
Acta Pharmacol Sin ; 32(8): 1063-70, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21743484

RESUMO

AIM: Toxoplasma gondii infection during pregnancy poses a serious risk to the fetus, therefore timely and accurate diagnosis is essential. The aim of this study was to estimate the frequency of congenital infection via evaluating mother's immunological status and the possibility to improving the diagnostic and therapeutic approaches. METHODS: Eighty five mothers with Toxoplasma seroconversion and their offspring were enrolled (among them, 2 spontaneous abortions were documented in the first trimester). Prenatal PCR diagnosis was carried out on 50 patients (60%), with 7 positive cases (14%). Morphological ultrasound scanning revealed anomalies in one fetus. Long-term follow-up included general physical examinations, serological status tested using Western blot, neuro-radiological, ophthalmologic and neurologic examinations, psychological and developmental tests, visual evoked potential tests and audiology tests, as well as anti-Toxoplasma treatment regimes. RESULTS: Fourteen (17%) of the infants were infected at one-year serological follow-up. Chi-square for linear trend of vertical transmission from the first to the third trimester was significant (P=0.009). Western blot analysis showed IgM and IgA in half of the infected infants. In 69 uninfected infants, anti-Toxoplasma IgG immunoblot analysis excluded infection within the 3 months in 18 infants (26%) and in the others within 6 months of life. The most relevant instrumental findings are described. CONCLUSION: Western blot analysis may help to evaluate infection within the 6 months of life. The accuracy of ultrasound imaging to determine the brain damage in the fetus and newborns is doubtful, and should be combined with MR imaging. Multistep approaches can improve the timing of postnatal follow-up.


Assuntos
Complicações Parasitárias na Gravidez/diagnóstico , Complicações Parasitárias na Gravidez/imunologia , Toxoplasmose Congênita/diagnóstico , Toxoplasmose Congênita/imunologia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Gravidez , Complicações Parasitárias na Gravidez/tratamento farmacológico , Resultado da Gravidez , Diagnóstico Pré-Natal/métodos , Estudos Prospectivos , Toxoplasmose Congênita/tratamento farmacológico
6.
BMC Med Imaging ; 11: 6, 2011 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-21435249

RESUMO

BACKGROUND: It is well-known that Epstein-Barr virus (EBV) can affect the central nervous system (CNS). CASE PRESENTATION: Herein the authors report unusual timely Magnetic Resonance Imaging (MRI) brain scan findings in an immunocompetent patient with EBV encephalitis. Diffusion weighted MRI sequence performed during the acute phase of the disease was normal, whereas the Fast Relaxation Fast Spin Echo T2 image showed diffuse signal intensity changes in white matter. The enhancement pattern suggested an inflammatory response restricted to the brain microcirculation. Acyclovir and corticosteroid therapy was administered. After three weeks, all signal intensities returned to normal and the patient showed clinical recovery. CONCLUSION: This report demonstrates that EBV in an immunocompetent adult can present with diffuse, reversible brain white matter involvement in the acute phase of mononucleosis. Moreover, our case suggests that a negative DWI sequence is associated with a favorable improvement in severe EBV CNS infection. More extensive studies are needed to assess what other instrumental data can help to distinguish viral lesions from other causes in the acute phase of disease.


Assuntos
Encefalite/imunologia , Encefalite/patologia , Hospedeiro Imunocomprometido/imunologia , Mononucleose Infecciosa/imunologia , Mononucleose Infecciosa/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Humanos , Masculino
7.
BMC Pediatr ; 11: 108, 2011 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-22111973

RESUMO

BACKGROUND: Studies of the apoptosis mechanisms involved in the pathogenesis of tuberculosis have suggested that Mycobacterium tuberculosis can actively interfere with the apoptosis of infected cells. In vivo studies have been performed in adult populations but have not focused on this process in children. In the present study, we analyzed spontaneous T lymphocyte (PBT) apoptosis in the peripheral blood of children with central nervous system tuberculosis (CNS TB), before and after chemotherapy, and compared the results with healthy controls. METHODS: A case-control study was conducted from January 2002 to June 2009. It included 18 children with CNS TB and 17 healthy controls. Spontaneous apoptosis of PBTs, including CD4+, CD8+ and CD8+/CD28+ T cells, was evaluated after 24 and 72 h of culture in complete medium, using the Annexin V detection test. Analysis was conducted before and after chemotherapy, and expression of the apoptotic markers CD95 (Fas) and Fas ligand (FasL) was evaluated. RESULTS: Higher percentages of apoptotic T cells and CD4 lymphocytes were isolated from children with acute phase CNS TB than from children in the control group (p < 0.05). This difference significantly decreased after 60 days of specific treatment. In children with CNS TB, high levels of Fas ligand expression were detected in lymphocyte populations, associated with a high percentage of Fas positive cells, before and after treatment. In contrast to the CD4+ apoptosis profile, we did not find any significant difference in total CD8+ cell apoptosis between children with acute phase disease and the control group. However, the percentage of apoptotic CD8+/CD28+ T cells was significantly higher in the children with acute phase disease than in the healthy controls. CONCLUSIONS: Our findings indicate that CNS TB in pediatric patients increases the sensitivity of CD4 and CD8+/CD28+ T cells to apoptosis, suggesting a hypoergic status of this infection. This could play a key role in the immunopathogenesis of this complicated form of TB. Interestingly, specific chemotherapy is able to normalize both apoptosis sensitivity and T-cell activation.


Assuntos
Apoptose/imunologia , Infecções Bacterianas do Sistema Nervoso Central/imunologia , Sistema Nervoso Central/imunologia , Mycobacterium tuberculosis/imunologia , Linfócitos T/metabolismo , Tuberculose do Sistema Nervoso Central/imunologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Proteína Ligante Fas/metabolismo , Feminino , Humanos , Ativação Linfocitária , Masculino , Mycobacterium tuberculosis/metabolismo , Linfócitos T/imunologia , Tuberculose do Sistema Nervoso Central/patologia , Receptor fas/metabolismo
8.
BMC Infect Dis ; 9: 199, 2009 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-20003257

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) is a protozoan diseases caused in Europe by Leishmania (L.) infantum. Asymptomatic Leishmania infection is more frequent than clinically apparent disease. Among HIV infected patients the risk of clinical VL is increased due to immunosuppression, which can reactivate a latent infection. The aims of our study were to assess the prevalence of asymptomatic L. infantum infection in HIV infected patients and to study a possible correlation between Leishmania parasitemia and HIV infection markers. METHODS: One hundred and forty-five HIV infected patients were screened for the presence of anti-Leishmania antibodies and L. infantum DNA in peripheral blood. Statistical analysis was carried out by using a univariate regression analysis. RESULTS: Antibodies to L. infantum were detected in 1.4% of patients. L. infantum DNA was detected in 16.5% of patients. Significant association for PCR-Leishmania levels with plasma viral load was documented (p = 0.0001). CONCLUSION: In our area a considerable proportion of HIV infected patients are asymptomatic carriers of L. infantum infection. A relationship between high HIV viral load and high parasitemic burden, possibly related to a higher risk of developing symptomatic disease, is suggested. PCR could be used for periodic screening of HIV patients to individuate those with higher risk of reactivation of L. infantum infection.


Assuntos
Infecções por HIV/complicações , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/epidemiologia , Adulto , Idoso , Anticorpos Antiprotozoários/sangue , Portador Sadio , DNA de Protozoário/sangue , Feminino , Infecções por HIV/parasitologia , Humanos , Imunoglobulina G/sangue , Itália/epidemiologia , Leishmania infantum/imunologia , Masculino , Pessoa de Meia-Idade , Parasitemia/epidemiologia , Prevalência , Análise de Regressão , Adulto Jovem
9.
Hum Vaccin ; 5(3): 172-6, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18802404

RESUMO

BACKGROUND: Recently, two Rotavirus (RV) vaccines were licensed in Italy, rendering RV illness a vaccine preventable disease. To assess the RV hospitalization rate in Italy, a study focused on the Regional hospital discharge forms (HDD) databases was carried out. RESULTS: Regional HDD databases from Piemonte, Veneto, Friuli-Venezia-Giulia and Marche were analyzed. A total of 434,335 hospitalizations were counted in the study timeframe and 13,234 VE diagnoses (3% of hospitalizations) were collected. A total of 8546 RVE cases (2% of hospitalizations, 64% of all VE) were observed, of which 1.2% were primary diagnoses (PD) and 0.8% secondary diagnosis (SD). The RVE hospitalization peak (4.9%) was observed at the age of 1 year (4.5% in 7-12 months of age) with a median hospital stay of 4.4 days (s.d +/- 4.2). Two deaths (out of 8546 RVE cases) were identified. PATIENTS AND METHODS: Regional HDD databases with the diagnosis of viral enteritis (VE) and RV enteritis (RVE) (ICD9-CM code 00861-69 and 008.8) in any position of the first 20 discharge diagnoses in children aged less or equal to 5 years between 2001 and 2005 were requested. CONCLUSION: Despite some limitations due to the HDD synthetic contents and low potential for clinical interpretation, the Regional HDD databases, including PD and SD, may be a useful tool for monitoring the clinical impact of RV vaccination introduction in Italy.


Assuntos
Coleta de Dados/métodos , Hospitalização/estatística & dados numéricos , Infecções por Rotavirus/epidemiologia , Pré-Escolar , Bases de Dados Factuais , Humanos , Lactente , Recém-Nascido , Itália/epidemiologia
10.
Arch Pharm (Weinheim) ; 342(5): 265-73, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19415659

RESUMO

A series of N-1H-indazole-1-carboxamides has been synthesized and their effects on both CDK1/cyclin B and the K-562 (human chronic myelogenus leukemia) cell line were evaluated. Using a computational model, we have observed that all the most active compounds 9e, f, i-n exhibited the same binding mode of purvanalol A in the ATP-binding cleft. Although they were able to moderately inhibit the leukemic cell line K-562 and to show inhibitory activity against the Cdc2-Cyclin B kinase in the low micromolar range, they turned out to be non-cytotoxic against HuDe (IZSL) primary cell cultures from human derm. These preliminary results are quite encouraging in view of the low toxicity demonstrated by the above-mentioned compounds.


Assuntos
Antineoplásicos/síntese química , Benzamidas/síntese química , Proteína Quinase CDC2/antagonistas & inibidores , Imidazóis/síntese química , Modelos Moleculares , Antineoplásicos/farmacologia , Benzamidas/farmacologia , Sítios de Ligação , Proteína Quinase CDC2/química , Proliferação de Células/efeitos dos fármacos , Ciclina B/antagonistas & inibidores , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Imidazóis/farmacologia , Células K562 , Ligação Proteica , Relação Estrutura-Atividade
11.
Cancer Lett ; 265(2): 289-97, 2008 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-18374481

RESUMO

Resistance to imatinib mesylate is an emergent problem in the treatment of Bcr-Abl expressing myelogenous leukemias and additional therapeutic strategies are required. We observed that galangin, a non-toxic, naturally occurring flavonoid was effective as anti-proliferative, and apoptotic agent in Bcr-Abl expressing K562 and KCL22 cells and in imatinib mesylate resistant K562-R and KCL22-R cells. Galangin induced an arrest of cells in G0-G1phase of cell cycle and a decrease in pRb, cdk4, cdk1, cycline B levels; moreover, it was able to induce a monocytic differentiation of leukemic Bcr-Abl+ cells. Of note, galangin caused a decrease in Bcl-2 levels and markedly increased the apoptotic activity of imatinib both in sensitive or imatinib-resistant Bcr-Abl+ cell lines. In contrast, flavonoids unable to modify the Bcl-2 intracellular levels, such as fisetin and chrysin, did not increase the apoptotic effect of imatinib. These data suggest that galangin is an interesting candidate for a combination therapy in the treatment of imatinib-resistant leukemias.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Flavonoides/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Apoptose/efeitos dos fármacos , Benzamidas , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Fase G1/efeitos dos fármacos , Humanos , Mesilato de Imatinib , Células K562 , Fase de Repouso do Ciclo Celular/efeitos dos fármacos
12.
J Med Microbiol ; 57(Pt 11): 1424-1426, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18927423

RESUMO

Mediterranean spotted fever (MSF) is a tick-borne acute febrile disease caused by Rickettsia conorii and characterized by fever, maculo-papular rash and a black eschar at the site of the tick bite ('tache noir'). We describe the case of a 58-year-old man affected by MSF who developed atrial fibrillation. The patient presented himself to the hospital after 7 days of fever, malaise and severe headache. Cardiac auscultation revealed a chaotic heart rhythm and an electrocardiogram confirmed atrial fibrillation with a fast ventricular response. Diagnosis of MSF was made after the appearance of a maculo-papular skin rash, and treatment with oral doxycycline was started. An immunofluorescence antibody test confirmed R. conorii infection. The patient recovered after 7 days of treatment. Cardiac arrhythmia is a rare complication of MSF. Inflammation may play a role in the pathogenesis of atrial fibrillation. R. conorii is an intracellular bacterium which could trigger atrial fibrillation. Our patient was previously healthy and had no reported history of cardiac disease. This suggests that heart function should be monitored in MSF patients even in the absence of underlying risk factors.


Assuntos
Fibrilação Atrial/etiologia , Febre Botonosa/complicações , Humanos , Masculino , Pessoa de Meia-Idade
13.
Trans R Soc Trop Med Hyg ; 102(4): 394-6, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18321542

RESUMO

The purpose of this study was to evaluate whether the risk of transfusion-transmitted visceral leishmaniasis was present in an area of western Sicily where the incidence of the disease is higher than the regional average. From May to December 2005, 1449 blood donors from Agrigento district (Sicily, Italy) were screened for the presence of anti-Leishmania antibodies by an indirect immunofluorescent antibody test (IFAT). Blood samples from IFAT-positive donors were examined by PCR to detect Leishmania DNA. Anti-Leishmania antibodies were found in 11 (0.75%) cases, among which Leishmania DNA was detected from four (36.4%). Particular techniques to inactivate different pathogens would be considered mandatory in the case of immunosuppressed recipients.


Assuntos
Doadores de Sangue , Portador Sadio/epidemiologia , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/transmissão , Adulto , Animais , Anticorpos Antiprotozoários/sangue , DNA de Protozoário/sangue , Feminino , Humanos , Itália/epidemiologia , Leishmania infantum/genética , Leishmania infantum/imunologia , Masculino , Pessoa de Meia-Idade
14.
Infez Med ; 16(1): 28-32, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18367880

RESUMO

Various critical issues still surround the management of toxoplasmosis in pregnant women and neonates. Although the study of specific antibodies remains an essential parameter for diagnosing materno-fetal infection and establishing time of infection, the method needs to be carefully and critically reviewed due to the distinctive immunological sensitivity of the neonate. We began a retrospective epidemiological study of the pre-natal management of Toxoplasma gondii (TG) infection to evaluate the incidence of congenital toxoplasmosis in children in a southern Italian area (Sicily). 230 children born between 1999 and 2005 to mothers with TG infection during pregnancy enrolled in the G. Di Cristina Children's Hospital of Palermo. Retrospective analysis of the maternal sample established that 150 (65%) of the 230 infants enrolled in the study were born to a mother with probable infection, while the remaining 80 (35%) were born to a mother with definite infection. To date, the results of the neonatal follow-up programme have confirmed the diagnosis of congenital infection in 16 infants (7%); for 43%, diagnosis was made early due to the presence, at birth or in the first month of life, of specific anti-TG IgM. Sequelae were observed in 8/16 infected infants. Sequelae in infected born to mothers with infection in the third trimester opens up the problematic issue of which therapeutic approach to adopt for these women: even without consensus support, a combined regimen of Pyrimethamine-Sulfadiazine could be advocated, even in the absence of prenatal diagnosis. Currently, the best diagnostic strategy involves the sequential or contemporaneous combination of more than one of the currently available methods, as no method on its own can ensure an appropriate level of accuracy.


Assuntos
Transmissão Vertical de Doenças Infecciosas , Complicações Parasitárias na Gravidez/diagnóstico , Toxoplasmose Congênita/transmissão , Toxoplasmose/diagnóstico , Toxoplasmose/transmissão , Feminino , Seguimentos , Humanos , Recém-Nascido , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Estudos Retrospectivos , Toxoplasmose/epidemiologia , Toxoplasmose Congênita/epidemiologia
15.
Infez Med ; 16(1): 21-7, 2008 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-18367879

RESUMO

Visceral leishmaniasis (VL) is endemic in Sicily (48 new cases in 2004, of which nine were in Agrigento). In southern Europe between 25-70 per cent of adult VL cases are related to HIV infection. The HIV cases have a high risk (1.5-9%) of developing VL either as a new infection or as the revival of a latent infection. We therefore carried out serologic screening to detect antibodies against L. infantum by IFAT in 1449 blood donors in Agrigento and the surrounding area (May-December 2005) and in 120 HIV+ in western Sicily, all of whom were asymptomatic and had no history of VL. L. DNA was assessed by nested PCR in blood samples of some seropositive donors. Of the 1449 blood donors, 11 (0.75%) were positive by IFAT and three of them were also positive in PCR. L. infantum seropositivity is most probably the expression of recent infection because the clearance of serum antibodies is rather fast (6-12 months) after VL. This is why blood donation by Leishmania seropositive donors, whether positive or negative by PCR, could constitute an infection risk especially for immunosuppressed recipients, who should receive deleukocyted blood. Moreover it could be useful to monitor HIV/Leishmania coinfection cases to avoid the risk of slatentization of L. infection when CD4+ levels are very low.


Assuntos
Anticorpos Antiprotozoários/sangue , Doadores de Sangue , Doenças Endêmicas , Soropositividade para HIV/sangue , Leishmania infantum/imunologia , Leishmaniose Visceral/sangue , Leishmaniose Visceral/diagnóstico , Adolescente , Adulto , Idoso , Animais , Feminino , Soropositividade para HIV/parasitologia , Humanos , Leishmaniose Visceral/epidemiologia , Masculino , Pessoa de Meia-Idade , Testes Sorológicos
16.
Clin Infect Dis ; 44(12): 1602-10, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17516404

RESUMO

BACKGROUND: To overcome some of the limitations of conventional microbiologic techniques, polymerase chain reaction (PCR)-based assays are proposed as useful tools for the diagnosis of visceral leishmaniasis. PATIENTS AND METHODS: A comparative study using conventional microbiologic techniques (i.e., serologic testing, microscopic examination, and culture) and a Leishmania species-specific PCR assay, using peripheral blood and bone marrow aspirate samples as templates, was conducted during an 8-year period. The study cohort consisted of 594 Italian immunocompetent (adult and pediatric) and immunocompromised (adult) patients experiencing febrile syndromes associated with hematologic alterations and/or hepatosplenomegaly. Identification of the infecting protozoa at the species level was directly obtained by PCR of peripheral blood samples, followed by restriction fragment-length polymorphism analysis of the amplified products, and the results were compared with those of isoenzyme typing of Leishmania species strains from patients, which were isolated in vitro. RESULTS: Sixty-eight patients (11.4%) had a confirmed diagnosis of visceral leishmaniasis. Eleven cases were observed in human immunodeficiency virus (HIV)-uninfected adults, 20 cases were observed in HIV-infected adults, and the remaining 37 cases were diagnosed in HIV-uninfected children. In the diagnosis of primary visceral leishmaniasis, the sensitivities of the Leishmania species-specific PCR were 95.7% for bone marrow aspirate samples and 98.5% for peripheral blood samples versus sensitivities of 76.2%, 85.5%, and 90.2% for bone marrow aspirate isolation, serologic testing, and microscopic examination of bone marrow biopsy specimens, respectively. None of 229 healthy blood donors or 25 patients with imported malaria who were used as negative control subjects had PCR results positive for Leishmania species in peripheral blood samples (i.e., specificity of Leishmania species-specific PCR, 100%). PCR and restriction fragment-length polymorphism analysis for Leishmania species identification revealed 100% concordance with isoenzyme typing in the 19 patients for whom the latter data were available. CONCLUSIONS: PCR assay is a highly sensitive and specific tool for the diagnosis of visceral leishmaniasis in both immunocompetent and immunocompromised patients and can be reliably used for rapid parasite identification at the species level.


Assuntos
Medula Óssea/parasitologia , Hospedeiro Imunocomprometido , Leishmania/genética , Leishmaniose Visceral/diagnóstico , Reação em Cadeia da Polimerase/métodos , Testes Sorológicos/métodos , Infecções Oportunistas Relacionadas com a AIDS , Adulto , Idoso , Algoritmos , Animais , Criança , Pré-Escolar , Feminino , Infecções por HIV/complicações , Humanos , Lactente , Itália , Leishmania/classificação , Leishmania/isolamento & purificação , Leishmaniose Visceral/sangue , Leishmaniose Visceral/genética , Leishmaniose Visceral/virologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
18.
Tuberculosis (Edinb) ; 87(4): 322-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17379576

RESUMO

Granulysin is a cytolytic protein of natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). Serum levels of granulysin are related to host cellular immunity. We used an ELISA to quantify granulysin serum levels in children with tuberculosis (TB), before and after chemotherapy. The study involved children affected by different clinical forms of TB (n=72) and healthy control children (n=150) from the same geographical area and of similar socio-economic background. Serum granulysin levels before the initiation of TB therapy were significantly lower in children with TB compared to controls, with the lowest levels being found in TB patients who were PPD skin test negative. No statistically significant differences were found between serum granulysin levels and clinical severity (mild/moderate or advanced pulmonary TB) or the clinical form (pulmonary or extra-pulmonary) of TB. At four months after completion of therapy, serum granulysin levels in children treated for TB were not significantly different to those observed in control children. This finding was paralleled by the increased in vitro mycobactericidal activity of sera from TB patients after completion of therapy. We propose that serum granulysin levels may provide a marker of disease activity in childhood TB and might be useful for monitoring improvement after chemotherapy.


Assuntos
Antígenos de Diferenciação de Linfócitos T/sangue , Biomarcadores/sangue , Tuberculose Pulmonar/sangue , Tuberculose/sangue , Antituberculosos/uso terapêutico , Criança , Pré-Escolar , Técnicas de Cocultura , Feminino , Humanos , Masculino , Tuberculose Meníngea/sangue , Tuberculose Meníngea/tratamento farmacológico , Tuberculose Pulmonar/tratamento farmacológico
19.
Am J Infect Control ; 35(4): 222-30, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17482993

RESUMO

BACKGROUND: Multidrug-resistant gram-negative bacilli (MDRGN) are an important cause of nosocomial infections in neonatal intensive care units (NICUs). We conducted a 1-year prospective surveillance study in an NICU to assess the epidemiology of MDRGN among newborns and the relative importance of acquisition routes. METHODS: Neonates admitted at the NICU of the Dipartimento Materno-Infantile, University Hospital, Palermo, Italy, from January 7, 2003, to January 6, 2004, were included in the study. Colonization of patients with MDRGN was assessed by cultures of rectal swabs sampled twice a week. Pulsed-field gel electrophoresis was used to determine relatedness among MDRGN isolates. Extended-spectrum beta-lactamases (ESBL) and metallo-beta-lactamases (MBL) production was investigated. The association between risk factors at admission and during the NICU stay was analyzed by multivariate logistic regression analysis. RESULTS: During the 12-month period January 7, 2003, through January 6, 2004, 1021 rectal swabs were cultured from 210 infants. One hundred sixteen infants (55.2%) were colonized by MDRGN. The monthly incidence of acquisition of MDRGN ranged between 12 and 53 cases per 1000 patient-days. Eighty-four (72.4%) of the 116 patients were cross colonized. Exclusive feeding by formula was significantly associated with cross transmission (RR=1.8, P=.02). Fifty-seven (49.1%) of the 116 infants were colonized by ESBL-producing Enterobacteriaceae. Feeding by formula was significantly associated with colonization by ESBL-producing Enterobacteriaceae (RR=1.6, P=.007), whereas breastfeeding proved to be protective (RR=0.5, P=.001). Ninety-two (43.8%) of the 210 infants received antibiotics during the NICU stay, but exposure to those most frequently administered, ampicillin-sulbactam and gentamicin, was not significantly associated with MDRGN colonization. CONCLUSION: The emerging picture of this study is that spread of MDRGN in an NICU may be the result of diffuse cross transmission and, consequently, of poor infection control procedures.


Assuntos
Infecção Hospitalar/microbiologia , Resistência a Múltiplos Medicamentos , Enterobacteriaceae/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/epidemiologia , Unidades de Terapia Intensiva Neonatal , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/transmissão , Eletroforese em Gel de Campo Pulsado , Enterobacteriaceae/classificação , Feminino , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/transmissão , Humanos , Recém-Nascido , Controle de Infecções , Itália/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Estudos Prospectivos , Vigilância de Evento Sentinela
20.
Infez Med ; 15(1): 24-9, 2007 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-17515672

RESUMO

The aim of our study was to evaluate the role of Salmonella spp in children hospitalised for acute gastroenteritis, and to study clinical and microbiological features of paediatric salmonellosis in our geographical area. In all, 540 patients admitted from March to September 2003 with symptoms of acute enteritis to the Infectious Diseases department of the "G. Di Cristina" hospital in Palermo were enrolled. Stool samples were collected within 48 hours of admission and tested for intestinal pathogens (bacterial, viral, parasites). Salmonella spp was detected in 18.5% of samples. The median age of infected children was 4.5 years. Salmonella enteritidis (49%) and Salmonella typhimurium (37%) were the most commonly identified genotypes. S. enteritidis infection was more frequently characterized by vomiting (65.3%) and dehydration (61.2%). Bloody diarrhoea was more common in S. typhimurium infection (40.5%). All strains were susceptible to ceftriaxone, while 40% of strains were resistant to tetracyclines and 37% to ampicillin.


Assuntos
Gastroenterite/epidemiologia , Infecções por Salmonella/epidemiologia , Salmonella/isolamento & purificação , Infecções por Adenoviridae/epidemiologia , Adolescente , Infecções por Campylobacter/epidemiologia , Criança , Pré-Escolar , Comorbidade , Desidratação/etiologia , Resistência a Medicamentos , Disenteria Bacilar/epidemiologia , Feminino , Febre/etiologia , Gastroenterite/complicações , Gastroenterite/microbiologia , Gastroenterite/virologia , Hospitalização , Humanos , Lactente , Recém-Nascido , Enteropatias Parasitárias/epidemiologia , Itália/epidemiologia , Masculino , Estudos Retrospectivos , Infecções por Rotavirus/epidemiologia , Salmonella/classificação , Salmonella/efeitos dos fármacos , Intoxicação Alimentar por Salmonella/epidemiologia , Intoxicação Alimentar por Salmonella/microbiologia , Infecções por Salmonella/complicações , Infecções por Salmonella/microbiologia , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA