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INTRODUCTION: Chorioamnionitis is an adverse condition in human pregnancy caused by many bacterial pathogens including Escherichia coli (E. coli); which has been associated with higher risk of preterm birth. We recently reported that human maternal decidua (MDec) tissue responds to E. coli infection by secreting extracellular heat-shock proteins (eHsp)-60, -70 and interlukin-1ß (IL-1ß). Previous studies have shown that progesterone (P4) regulates the immune response, but it is unknown whether P4 inhibits the secretion of eHsp. The aim of this investigation was to determine the role of P4 on the secretion of eHsp-27, -60, -70 and IL-1ß in MDec after 3, 6, and 24 h of E. coli infection. METHODS: Nine human feto-maternal interface (HFMi) tissues were included and mounted in the Transwell culture system. Only the maternal decidua (MDec) was stimulated for 3, 6 and 24 h with E. coli alone or in combination with progesterone and RU486. After each treatment, the HFMi tissue was recovered to determine histological changes and the culture medium recovered to evaluate the levels of eHsp-27, -60, -70 and IL-1ß by ELISA and mRNA expression by RT-PCR. RESULTS: No structural changes were observed in the HFMi tissue treated with P4 and RU486. However, stimulation with E. coli produces diffuse inflammation and ischemic necrosis. E. coli induced infection decreases, in time- and dose-dependent manner, eHsp-27 and increases eHsp-60, eHsp-70 and IL-1ß levels. In contrast, incubation of HFMi tissue with E. coli + P4 reversed eHsp and IL-1ß secretion levels relative to E. coli stimulation group but not relative to the control group. The same profile was observed on the expression of eHsp-27 and eHsp-60. DISCUSSION: we found that progesterone modulates the anti-inflammatory (eHsp-27) and pro-inflammatory (eHsp-60 and eHsp-70) levels of eHsp induced by E. coli infection in human choriodecidual tissue. eHsp-60 and eHsp-70 levels were not completely reversed; maintaining the secretion of IL-1ß, which has been associated with adverse events during pregnancy.

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Reduced susceptibility to vancomycin has been reported among clinical isolates of Staphylococcus in previous studies. The present study describes a heteroresistant Staphylococci strain from the cerebrospinal fluid of a 17 day-old premature male infant with neonatal meningitis. Screening was done for 44 strains of coagulase-negative staphylococci using Wong 's techniques (Disk-agar method with vancomycin-salt agar to demonstrate satellitism around an aztreonam disk). Strains were susceptible to vancomycin as disclosed by an automated antimicrobial susceptibly test (Microscan System Dade Behring). This is the first report of heterogeneous resistance to vancomycin in Mexico and an early warning for the possible emergence of vancomycin resistance among coagulase-negative staphylococcus in our country.

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La susceptibilidad reducida a vancomicina ha sido encontrada en estudios previos de aislamientos clínicos de pacientes con evolución médica inadecuada. Presentamos un caso con aislamiento de una cepa de staphylococcus haemolyticus con susceptibilidad reducida a vancomicina obtenida de un paciente recién nacido con neuroinfección a los 17 días de vida con evolución clínica adecuada después de 21 días de tratamiento. Se realizó análisis de susceptibilidad intermedia a 44 cepas de staphylococcus coagulasa negativa mediante las técnicas descritas por Wong (método de disco en agar adicionado con sal de vancomicina en concentración ≥ de 8 μg/ml en el que se demuestra satelitismo alrededor de un disco de aztreonam). La cepa fue susceptible a vancomicina al analizar la sensibilidad por un método automatizado (Sistema MicroScanR, Dade Behring). Este es el primer informe de heteroresistencia en México y una alerta temprana de la posible emergencia de staphylococcus con algún tipo de resistencia a vancomicina.

Reduced susceptibility to vancomycin has been reported among clinical isolates of Staphylococcus in previous studies. The present study describes a heteroresistant Staphylococci strain from the cerebrospinal fluid of a 17 day-old premature male infant with neonatal meningitis. Screening was done for 44 strains of coagulase-negative staphylococci using Wong 's techniques (Disk-agar method with vancomycin-salt agar to demonstrate satellitism around an aztreonam disk). Strains were susceptible to vancomycin as disclosed by an automated antimicrobial susceptibly test (Microscan System Dade Behring). This is the first report of heterogeneous resistance to vancomycin in Mexico and an early warning for the possible emergence of vancomycin resistance among coagulase-negative staphylococcus in our country.

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Background. Guttate psoriasis is associated with infections by Streptococcus pyogenes and cross-reaction between skin and streptococcal antigens have been reported, suggesting an autoimmune component in the disease. Methods. In this work, the authors looked for antibodies against S. pyogenes M-5 antigens by immunoblot in 52 sera of psoriasis patients and in 52 sera of normal individuals. Histological and immunohistochemical analysis in skin biopsies from lesions of another group of 16 clinically diagnosed guttate psoriasis patients and four healthy controls were also carried out. Results. All guttate psoariasis patients studied (11) had IgG antibodies that intensively recognized three different proteins of 70,60 and 14 kDa, as compared to sera from patients with other forms of psoriasis or from healthy controls. The diagnosis of psoariasis was confirmed in 14 of the patients by hematoxylin-eosin staining. Of the other two patients, one was diagnosed as parapsoriasis and the other as liquen. By indirect immunofluorescence (IFI), all 14 psoriatic patients had autoantibodies against their own lesional skin that did not recognized normal skin from control subjects or from the two non-psoriatic patients. The parapsoriatic and the liquen patients did not have autoantibodies. A rabbit immune serum against S. pyogenes antigens reacted with lesional skin from the 14 guttate psoriatic patients, but not with normal skin from controls or with lesional skin from the 2 non-psoriatic patients. Conclusions. The recognition by immunoblot of streptococcal antigens by serum of guttate psoriasis patients, the presence of autoantibodies against their own skin, and recognition of the same skin antigens by anti-streptococcal rabbit antibodies confirm the participation of the immune system and of streptococcal infection in guttate psoriasis

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