Klatskin-type cholangiocarcinoma is a rare tumor, bearing a very poor prognosis: at diagnosis, most patients can only undergo palliation. Evaluation of outcome, mean survival and quality of life was ...performed in patients with unresectable hilar cholangiocarcinoma treated with multimodality approach in comparison with surgical palliation, biliary stenting or brachytherapy alone. Twenty-six patients with hilar cholangiocarcinoma were studied: 16 patients were enrolled in the multimodality protocol (bilateral biliary drainage; Iridium-192 brachytherapy; plastic endoprosthesis or metallic stent positioning and external radiotherapy plus systemic chemotherapy), 5 patients underwent surgical palliation and 5 percutaneous decompression alone. Nine patients completed the protocol and 7 were treated with brachytherapy followed by biliary stenting alone. The multimodality approach obtained mean survival (10 months) similar to that for surgery and higher than that of the brachytherapy and metallic stenting groups (6 and 2.75 months, respectively). The average hospital stay (15 days) was lower than that of the surgical group (20 days). A multimodality approach is a suitable alternative to palliative surgery of unresectable hilar cholangiocarcinoma.
Small, isolated populations may experience increased extinction risk due to reduced genetic variability at important functional genes, thus decreasing the population's adaptive potential. The major ...histocompatibility complex (MHC), a key immunological gene cluster, usually shows high variability maintained by positive or balancing selection in response to challenges by pathogens. Here we investigated for the first time, the variability of 3 MHC class II genes (DRB1, DQA1, and DQB1) in 94 samples collected from Italian wolves. The Italian wolf population has been long isolated south of the Alps and is presently recovering from a recent bottleneck that decreased the population to less than 100 individuals. Despite the bottleneck, Italian wolves show remarkable MHC variability with 6-9 alleles per locus, including 2 recently described alleles at DRB1. MHC sequences show signatures of historical selective pressures (high d N/d S ratio, ω > 1.74) but no evidence of ongoing selection. Variation at the MHC genes and 12 background microsatellite loci were not apparently affected by the recent bottleneck. Although MHC alleles of domestic dog origin were detected in 8 genetically admixed individuals, these alleles were rare or absent in nonadmixed wolves. Thus, despite known hybridization events between domestic dogs and Italian wolves, the Italian wolf population does not appear affected by deep introgression of domestic dog MHC alleles.
Lorentz symmetry breaking at very high energies may lead to photon dispersion relations of the form omega^2=k^2+m^2+xi_n k^2(k/M_Pl)^n with new terms suppressed by a power n of the Planck mass M_Pl. ...We show that first and second order terms of size xi_1 >~ 10^(-14) and xi_2 >~ 10^(-6), respectively, would lead to a photon component in cosmic rays above 10^(19) eV that should already have been detected. Only effects suppressed by at least third order in the Planck scale appear consistent with observations.
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