Effectiveness and toxicity of helical tomotherapy for patients with locally recurrent nasopharyngeal carcinoma.

PURPOSE: We assessed therapeutic outcomes of reirradiation with helical tomotherapy (HT) for locoregional recurrent nasopharyngeal carcinoma (LRNPC) patients. METHODS AND MATERIALS: Treatment outcomes were evaluated retrospectively in 17 consecutive LRNPC patients receiving HT between 2006 and 2012. Median age was 57 years and most patients (n = 13) were male. Simultaneous systemic therapy was applied in 5 patients. Initial treatment covered the gross tumor volume with a median dose of 70 Gy (60-81.6 Gy). Reirradiation was confined to the local relapse region with a median dose of 63 Gy (50-70.2 Gy), resulting in a median cumulative dose of 134 Gy (122-148.2 Gy). The median time interval between initial and subsequent treatment was 42 months (11-126). RESULTS: The median follow-up for the entire cohort was 23 and 35 months for survivors. Three patients (18 %) developed both local and distant recurrences and only one patient (6 %) suffered from isolated local recurrence. Two-year actuarial DFS and LC rates were 74 and 82 %, respectively. Two-year OS rate was 79 %. Acute and late grade 2 toxicities were observed in 8 patients (47 %). No patient experienced late grade ≥3 toxicity. Late toxicity included fibrosis of skin, hypoacusia, dysphagia, and xerostomia. Patients with higher Karnofsky performance status scores associated with a lower risk of mortality (HR 0.85, p = 0.015). CONCLUSION: Reirradiation with HT in patients with LRNPC is feasible and yields encouraging results in terms of local control and overall survival with acceptable toxicity.

Peritonitis espontanea en el cirrótico: nuestra experiencia / Spontaneus peritonitis in cirrhosis: our experience

Debido a la escasez de publicaciones en nuestro país, se analiza retrospectivamente la incidencia de peritonitis espontánea (PE) observados durante 2 años, en 76 episodios de ascitis provenientes de 63 pacientes con cirrosis hepática. Trece pacientes (17%) presentaron PE y la relación hombre-mujer fue de 5 a 1; el 70% de los gérmenes encontrados en el líquido ascítico fue de origen entérico, principalmente Escherichia Coli. En tres pacientes el diagnóstico se efectuó por el recuento de polinucleares y la clínica, a pesar del cultivo negativo. No hubo diferencias significativas en la presencia de complicaciones o alteraciones humorales al ingreso entre pacientes con ascitis estériles y con PE, pero sí con la mortalidad que fue de 7,9% (5/63) en los primeros y de 38% (5/13) en las ascitis infectadas. El 80% de los fallecidos presentaban falla renal en el final de la evolución y una vinculación con el uso de aminoglucósidos no puede ser descartado. La peritonitis espontánea en el cirrótico, buscada rutinariamente, parece tener la misma incidencia en nuestro medio que la descripta en la literatura

Lipopolysaccharide changes and cytoplasmic polyphosphate granule accumulation in Pseudomonas aeruginosa during growth on hexadecane.

Pseudomonas aeruginosa ATCC 9027 grew on 0.5% (v/v) hexadecane as a sole carbon source in a chemically defined medium which required the addition of Fe3+ and Ca2+. There was a variable and extended lag period before an active growth rate was attained. Visible light microscopic evidence revealed that the bacteria did not adhere to hexadecane droplets suggesting the absence of a bioemulsifier. When compared with glucose-grown cells, hexadecane-grown cells produced 75% less lipopolysaccharide (on a total protein basis); this lipopolysaccharide contained 30-40% less carbohydrate, yet 50-75% more 2-keto-3-deoxyoctonate. These chemical changes made the cell surface appear more hydrophobic when tested in a biphasic hydrophobicity index system. Electron microscopy of thin sections and freeze etchings revealed hexadecane-grown cells contained granules which were judged to be polyphosphate by energy dispersive X-ray analysis. There was no apparent major morphological envelope alteration within the two cell types.