Cellular stress responses of Eleginops maclovinus fish injected with Piscirickettsia salmonis and submitted to thermal stress.

Fluctuations in ambient temperature along with the presence of pathogenic microorganisms can induce important cellular changes that alter the homeostasis of ectothermic fish. The aim of this study was to evaluate how sudden or gradual changes in environmental temperature together with the administration of Piscirickettsia salmonis modulate the transcription of genes involved in cellular stress response in the liver of Eleginops maclovinus. Fish were subjected to the following experimental conditions in duplicate: C- 12 °C: Injection only with culture medium, C+ 12 °C: Injection with P. salmonis, AM 18 °C: Injection only with culture medium under acclimation at 18 °C, AB 18 °C: Injection with P. salmonis under acclimation at 18 °C, SM 18 °C: Injection only with culture medium and thermal shock at 18 °C and SB 18 °C: Injection with P. salmonis and thermal shock at 18 °C and sampling at 4-, 8-, 12-, 16- and 20-day post injection (dpi). The genes implied in the heat shock response (HSP70, HSC70, HSP90, and GRP78), apoptosis pathway (BAX and SMAC/Diablo), ubiquitination (E2, E3, ubiquitin, and CHIP), and 26 proteasome complex (PSMB7, PSMC1, and PSMA2) showed expression profiles dependent on time and type of injection applied. All the genes greatly increased their expression levels at day 16 and showed moderate increases at day 20, except for PSMA2 which showed a higher increase between 4- and 12-day post challenges. Our results suggest that the changes observed at the final days of the experiment are due to temperature more than P. salmonis.

Ectoparasite Caligus rogercresseyi modifies the lactate response in Atlantic salmon (Salmo salar) and Coho salmon (Oncorhynchus kisutch).

Although Caligus rogercresseyi negatively impacts Chilean salmon farming, the metabolic effects of infection by this sea louse have never been completely characterized. Therefore, this study analyzed lactate responses in the plasma, as well as the liver/muscle lactate dehydrogenase (LDH) activity and gene expression, in Salmo salar and Oncorhynchus kisutch infested by C. rogercresseyi. The lactate responses of Atlantic and Coho salmon were modified by the ectoparasite. Both salmon species showed increasing in plasma levels, whereas enzymatic activity increased in the muscle but decreased in the liver. Gene expression was overexpressed in both Coho salmon tissues but only in the liver for Atlantic salmon. These results suggest that salmonids need more energy to adapt to infection, resulting in increased gene expression, plasma levels, and enzyme activity in the muscles. The responses differed between both salmon species and over the course of infection, suggesting potential species-specific responses to sea-lice infection.

Identification, characterization and modulation of ferritin-H in the sub-Antarctic Notothenioid Eleginops maclovinus challenged with Piscirickettsia salmonis.

Ferritin is a major iron storage protein essential not only in the infectious process, but also in any circumstance generating oxidative stress. In this study, the cDNA coding sequence of ferritin-H was obtained from the sub-Antarctic Notothenioid fish Eleginops maclovinus through transcriptomic analysis of the head kidney. This sequence contained a 534 bp open reading frame that coded for a 177 amino acid protein with a molecular weight of 20,786.2 Da and a theoretical pI of 5.56. The protein displayed a region of iron putative response elements in the 5'UTR, two putative ferritin iron-binding region signatures, and seven characteristic amino acids with ferroxidase functions. Phylogenetic analysis related this sequence to ferritin-H sequences of other Antarctic Notothenioid fish, sharing 96.61% similarity. Constitutive gene expression analysis in different organs revealed increased ferritin-H gene expression in the gills, spleen, muscle, and liver. After infection with two bacterial strains of Piscirickettsia salmonis (LF-89 and Austral-005), ferritin-H was differentially expressed depending on bacterial strain and tissue. This study provides relevant information towards understanding the iron metabolism of a sub-Antarctic Notothenioid fish.

Early-life exposure to combustion-derived particulate matter causes pulmonary immunosuppression.

Elevated levels of combustion-derived particulate matter (CDPM) are a risk factor for the development of lung diseases such as asthma. Studies have shown that CDPM exacerbates asthma, inducing acute lung dysfunction and inflammation; however, the impact of CDPM exposure on early immunological responses to allergens remains unclear. To determine the effects of early-life CDPM exposure on allergic asthma development in infants, we exposed infant mice to CDPM and then induced a mouse model of asthma using house dust mite (HDM) allergen. Mice exposed to CDPM+HDM failed to develop a typical asthma phenotype including airway hyper-responsiveness, T-helper type 2 (Th2) inflammation, Muc5ac expression, eosinophilia, and HDM-specific immunoglobulin (Ig) compared with HDM-exposed mice. Although HDM-specific IgE was attenuated, total IgE was twofold higher in CDPM+HDM mice compared with HDM mice. We further demonstrate that CDPM exposure during early life induced an immunosuppressive environment in the lung, concurrent with increases in tolerogenic dendritic cells and regulatory T cells, resulting in the suppression of Th2 responses. Despite having early immunosuppression, these mice develop severe allergic inflammation when challenged with allergen as adults. These findings demonstrate a mechanism whereby CDPM exposure modulates adaptive immunity, inducing specific antigen tolerance while amplifying total IgE, and leading to a predisposition to develop asthma upon rechallenge later in life.

Retreatment management strategies when first-line tuberculosis therapy fails.

SETTING: Public ambulatory centers in northern Lima, Peru. OBJECTIVE: To compare two retreatment strategies in Category I failures. DESIGN: Retrospective cohort study of Category I failures enrolled between February 1997 and October 2001. Strategy A was a nationwide approach, applying a Category II regimen; if that regimen failed, a standardized regimen including second-line drugs was used. Strategy B was a pilot protocol designed to diagnose and treat multidrug-resistant tuberculosis (MDR-TB); this strategy included drug susceptibility testing (DST) and eliminated the Category II regimen. RESULTS: Of 125 patients that Category I failed to cure, 73 entered Strategy A and 52 entered Strategy B. Almost 90% of those with DST results had MDR-TB. Strategy B was three times more likely than Strategy A to cure patients (79% vs. 38%, RR = 2.9, 95% CI 1.7-5.1) and five times more likely to cure patients than the Category II regimen alone (79% vs. 15%, RR 5.2, 95% CI 3.0-9.2). Strategy B also significantly reduced delays to MDR-TB diagnosis and to the initiation of MDR-TB therapy. CONCLUSIONS: Under program conditions, a retreatment strategy based on DST and eliminating the Category II regimen can improve clinical outcomes among Category I treatment failures found to have active, infectious MDR-TB.

estudio clínico controlado aleatorio abierto de la eficacia y seguridad de "gentamicina-clindamicina" Vs. "pefloxacina-metronidazol" en el tratamiento de la endometritis post-cesárea

Con el fin de comparar la eficacia y seguridad de dos regímenes terapéuticos(clindamicina-gentamicina y pefloxacina-metronidazol) en el tratamiento de la endometritis post-cesárea, se incluyeron 71 pacientes que fueron sometidas a parto abdominal de urgencia en el Instituto Materno Infantil del 1§ de septiembre de 1993 al 31 de agosto de 1994 y que se presentaron endometritis post-cesárea diagnosticada por la presencia de tres de nueve criterios utilizados en el Servicio de Sépticas. Se asignaron de manera aleatoria de manera a uno de los dos grupos de tratamiento: gentaicina-clindamicina o metronidazol-pefloxacina. Se estudió la eficacia terapéutica mediante la comparación del tiempo de desaparición de la fiebre, la evolución clínica, los fracasos terapéuticos y las complicaciones. También se evaluó la seguridad de los dos regímenes. Se aplicó la prueba t de student y Chi cuadrado para significación estadística(a=0.05). Resultados: La seguridad se determinó en 68 pacientes que asistieron al control el día 5 de tratamiento y la eficacia en 63 pacientes que asistieron al control del día 7. Los cultivos de endometrio mostraron gérmenes anaerobios en el 48 por ciento de las pacientes y se aislaron en promedio 1.9 gérmenes por paciente. No hubo diferencias entre los dos grupos de tratamiento en cuanto a desaparición de la fiebre(p=0.82), tasa de mejoría (p=0.49), complicaciones (p=0.44). La sensibilidad antibiótica de los gérmenes aerobios fue alta para los antibióticos utilizados y no se encontró b lactamasa en los cuatro casos en los que se aislo N. gonorrohae. Conclusiones: La asociación clindamicina-gentamicina fue tan eficaz como la asociación pefloxacina-metronidazol en el tratamiento de la endometritis post-cesárea por lo que ésta última asociación se podría tener como una alternativa terapéutica

Frecuencia de marcadores serológicos del virus B en maternas

Se estudiaron 175 madres y sus hijos determinando los marcadores del virus de Hepatitis B, para establecer la frecuencia de portadores de esta infección, que fue del 8.5 por ciento. Se determinó la ausencia de relación entre la seropositividad y los factores de riesgo de ser portador. No se encontraron marcadores en la sangre del cordon umbilical de los neonatos. Se hacen recomendaciones tanto en el control prenatal como sobre las medidas terapéuticas a ser tomadas

Desparasitacion periodica y cambios en el estado nutricional de ninos con dietas hipoproteicas. / Periodic deworming and changes in nutritional status of children with hypoprotein diets

En dos grupos de ninos pre-escolares se analizo el efecto de la desparasitacion periodica - 2 veces al ano - con mebendazole. Despues de 13 meses, el grupo que recibio el tratamiento mostro una mejoria significante en el estado nutricional, en relacion con el grupo testigo si se mantienen controladas las variables socio-economicas y el nivel de salud. Como politica nacional de salud publica, la desparasitacion periodica puede ser una intervencion positiva desde el punto de vista costo-beneficio

Pipamperone (Dipiperon), a useful sedative neuroleptic drug in troublesome chronic psychotic patients.

In 13 chronic schizophrenic patients (age range: 22-61 years) with troublesome behaviour and/or dysthymia, who were on maintenance treatment with a combination of incisive neuroleptics and sedative drugs, the sedative therapy was abruptly replaced by pipamperone. Dosage was gradually increased from 80 mg/day to an optimal level of 160-320 mg/day. The patients' condition was assess by Overall's "Factor Construct Rating Scale" and a 4-item questionnaire for sleep disorders. Pipamperone proved to be very rapidly effective in patients with prominent sleep disorders and/or agitation. Improvement was also significant for various other items of the two rating scales. No pipamperone-related side-effects were observed or reported.