Leishmania mexicana amastigotes inhibit p38 and JNK and activate PI3K/AKT: role in the inhibition of apoptosis of dendritic cells.

Leishmania mexicana is the causal agent of cutaneous leishmaniasis in Mexico. Dendritic cells (DC) are one of the host cells of Leishmania parasites. Intracellular microorganisms inhibit host cell apoptosis as a strategy to ensure their survival in infected cells. We have previously shown that Leishmania mexicana promastigotes and amastigotes inhibit camptothecin-induced apoptosis of monocyte-derived dendritic cells (moDC), but the mechanisms underlying the inhibition of apoptosis of DC by Leishmania have not been established. MAP kinases and PI3K participate in the process of apoptosis and are modulated by different species of Leishmania. As shown in this study, the infection of moDC with L. mexicana amastigotes diminished significantly the phosphorylation of the MAP kinases p38 and JNK. The inhibition of both kinases diminished significantly DNA fragmentation in moDC stimulated with camptothecin. On the other hand, L. mexicana amastigotes were able to activate the anti-apoptotic pathways PI3K and AKT. Our results indicate that L. mexicana amastigotes have the capacity to diminish MAP kinases activation and activate PI3K and AKT, which is probably one of the strategies employed by L. mexicana amastigotes to inhibit apoptosis in the infected moDC.

Present and past perspectives on Clostridium difficile infection. / Perspectivas históricas y vigentes sobre la infección por Clostridium difficile.

Clostridium difficile is a Gram-positive bacillus that has become one of the main hospital-acquired human gastrointestinal infections in recent years. Its incidence is on the rise, involving more virulent strains, affecting new and previously uncontemplated groups of patients, and producing changes in clinical presentation and treatment response that influence disease outcome. Early diagnosis and disease stratification based on the severity of C.difficile infection are essential for therapeutic management and the implementation of containment measures. However, the speed at which new strains with greater pathogenicity are developing is surpassing that of the development of new drugs, making it necessary to validate other therapeutic options. The present article is a review of the epidemiologic, pathophysiologic, diagnostic, and therapeutic aspects of C.difficile infection, from its first isolation to the present date, that aims to contribute to the preparation of general physicians and specialists, so that patients with this infection receive opportune and quality medical attention.

[A case of neonatal malaria in Spain]. / Un caso de paludismo neonatal en España.

We report a case of neonatal malaria born in Spain. It is about a female newborn whose mother lived the first eight months of her pregnancy in Ecuatorial Guinea. Although our patient was well, in the third week of her life she developed fever mostly in mornings without any other symptoms except pallor. She kept a good physical state in any moment. In complementary proves we remark: anaemia and thrombocytopenia; as well Plasmodium falciparum ruin was found in blood smears. Treatment with mefloquine was successfully, blood smears was negative of parasites in the eighth day and hemogram was restoring normal. This article suggests neonatal malaria must be considered in those newborns suspected congenital infection born from mothers who have travelled to risk countries or immigrated from endemic areas. Also we remark that malaria clinic development in newborns is nonspecific and indistinguishable from other congenital infections.

[Nijmegen breakage syndrome associated with pulmonary lymphoma]. / Linfoma pulmonar asociado a síndrome de Nijmegen.

Nijmegen breakage syndrome is a rare autosomal recessive disorder characterized by a peculiar dysmorphic syndrome (microcephaly, "bird-like" facies, short stature), combined immunodeficiency with recurrent infections, X-ray hypersensitivity and predisposition to malignancy, mainly lymphomas, as a consequence of chromosome instability due to anomalies in the repair of double-stranded DNA breaks.We present a 6-year-old boy with Nijmegen breakage syndrome, who developed a large B-cell non-Hodgkin's lymphoma, localized in the lung without nodal involvement.

[Pulmonary symptoms of primary immunodeficiency diseases]. / Manifestaciones pulmonares de las immunodeficiencias primarias.

OBJECTIVE: Patients who lack major components of the immune system carry an increased risk for severe and recurrent pulmonary infections at those respiratory sites were the deficient component would, in the normal state, have its greatest concentration. We report different pulmonary manifestations in pediatric patients with primary immunodeficiency disease (PID). PATIENTS AND METHODS: We studied 44 children younger than 14 years old, who were diagnosed of PID in our pediatric department between January 1990 and May 1996. RESULTS: Antibody deficiencies were the most frequent disorders (27/44; 61.3%) followed by PID associated with or secondary to other disorders (10/44; 22.7%) and defects of phagocyte function (5/44; 11.3%). Twenty-seven patients (61.3%) showed relevant pulmonary manifestations that required assistance in the division of pediatric pulmonology. Bronchial responsiveness was seen in 17/27, 11/27 had recurrent pneumonias with development of bronchiectasis in 7/27. Opportunistic or severe pneumonias leading to acute respiratory failure were diagnosed in 9/27. Necrotizing pneumonias leading to development of pneumatoceles, cavities or abscesses was seen in 3/27 with the same rate for lymphoid interstitial pneumonia. Respiratory symptoms were the first manifestations of PID in 19/27 (70.3%). CONCLUSIONS: The findings of the study emphasize the responsibility of the pediatric pulmonologists in avoiding the delayed diagnosis of PID since the prognosis depends on the precocity of diagnosis.