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1.  Raman spectroscopy as a potentialmethod for the detection of extremely halophilic archaea embedded in halite in terrestrial and possibly extraterrestrial samples 
Journal of Raman spectroscopy : JRS  2009;40(12):1996-2003.
Evidence for the widespread occurrence of extraterrestrial halite, particularly on Mars, has led to speculations on the possibility of halophilic microbial forms of life; these ideas have been strengthened by reports of viable haloarchaea from sediments of geological age (millions of years). Raman spectroscopy, being a sensitive detection method for future astrobiological investigations onsite, has been used in the current study for the detection of nine different extremely halophilic archaeal strains which had been embedded in laboratory-made halite crystals in order to simulate evaporitic conditions. The cells accumulated preferentially in tiny fluid inclusions, in simulation of the precipitation of salt in natural brines. FT-Raman spectroscopy using laser excitation at 1064 nm and dispersive micro Raman spectroscopy at 514.5 nm were applied. The spectra showed prominent peaks at 1507, 1152 and 1002 cm−1 which are attributed to haloarchaeal C50 carotenoid compounds (mainly bacterioruberins). Their intensity varied from strain to strain at 1064-nm laser excitation. Other distinguishable features were peaks due to peptide bonds (amide I, amide III) and to nucleic acids. No evidence for fatty acids was detected, consistent with their general absence in all archaea.
These results contribute to a growing database on Raman spectra of terrestrial microorganisms from hypersaline environments and highlight the influence of the different macromolecular composition of diverse strains on these spectra.
PMCID: PMC3207228  PMID: 22058585
Raman spectroscopy; extremely halophilic archaea; halite; astrobiology; fluid inclusions; carotenoids; bacterioruberins; Martian subsurface
2.  Investigating the Effects of Simulated Martian Ultraviolet Radiation on Halococcus dombrowskii and Other Extremely Halophilic Archaebacteria 
Astrobiology  2009;9(1):104-112.
The isolation of viable extremely halophilic archaea from 250-million-year-old rock salt suggests the possibility of their long-term survival under desiccation. Since halite has been found on Mars and in meteorites, haloarchaeal survival of martian surface conditions is being explored. Halococcus dombrowskii H4 DSM 14522T was exposed to UV doses over a wavelength range of 200–400 nm to simulate martian UV flux. Cells embedded in a thin layer of laboratory-grown halite were found to accumulate preferentially within fluid inclusions. Survival was assessed by staining with the LIVE/DEAD kit dyes, determining colony-forming units, and using growth tests. Halite-embedded cells showed no loss of viability after exposure to about 21 kJ/m2, and they resumed growth in liquid medium with lag phases of 12 days or more after exposure up to 148 kJ/m2. The estimated D37 (dose of 37 % survival) for Hcc. dombrowskii was ≥ 400 kJ/m2. However, exposure of cells to UV flux while in liquid culture reduced D37 by 2 orders of magnitude (to about 1 kJ/m2); similar results were obtained with Halobacterium salinarum NRC-1 and Haloarcula japonica. The absorption of incoming light of shorter wavelength by color centers resulting from defects in the halite crystal structure likely contributed to these results. Under natural conditions, haloarchaeal cells become embedded in salt upon evaporation; therefore, dispersal of potential microscopic life within small crystals, perhaps in dust, on the surface of Mars could resist damage by UV radiation.
PMCID: PMC3182532  PMID: 19215203
Halococcus dombrowskii; Simulated martian UV radiation; LIVE/DEAD staining; Halite fluid inclusions; UV transmittance and reflectance; Desiccation
3.  Haematopoietic stem cell transplantation for vasculitis including Behçet's disease and polychondritis: a retrospective analysis of patients recorded in the European Bone Marrow Transplantation and European League Against Rheumatism databases and a review of the literature 
Annals of the Rheumatic Diseases  2006;66(2):202-207.
To evaluate the feasibility of haematopoietic stem cell transplantation (HSCT) in vasculitis.
This is a retrospective analysis of patients who had received HSCT for vasculitic diseases and have been reported to the European League Against Rheumatism autoimmune disease or European Bone Marrow Transplantation ProMISe databases. Information about the disease and outcome was obtained by a questionnaire sent to the referring centres. Response of the disease to HSCT was defined as partial or complete responses according to the ability to reduce immunosuppression after HSCT. In addition, the Medline database was searched for reports on HSCT in patients with vasculitis.
Detailed information was obtained for 15 patients, whose median age at HSCT was 37 years. The diagnoses were cryoglobulinaemia in four patients, Behçet's disease in three patients, Wegener's granulomatosis in three patients, and undifferentiated vasculitis, Churg–Strauss angiitis, polychondritis, Takayasu arteritis and polyarteritis nodosa in one patient each. 14 patients received autologous HSCT and 1 an allogeneic HSCT as the first transplant. In three patients, further transplantation was given because of relapse. The overall response, including all consecutive transplantations (HSCT/patient, n = 1–3, median 1.3) to HSCT, was 93%, with 46% complete responses and 46% partial responses; median (range) duration of response at the time of reporting was 45 (16–84) months. Three patients died, one from advanced disease, one from cancer and one from graft‐versus‐host disease. The Medline search showed five other patients who were effectively treated with HSCT for vasculitic diseases.
This retrospective study suggests that autologous HSCT is feasible for vasculitis. Its value remains to be tested in prospective controlled studies.
PMCID: PMC1798517  PMID: 16950809
4.  Outcome of Allogeneic Stem Cell Transplantation Following Reduced-Intensity Conditioninig Regimen in Patients With Idiopathic Myelofibrosis: the G.I.T.M.O. Experience 
Allogeneic stem cell transplantation (SCT) is a potentially curative treatment for myelofibrosis (MI), though limited by a high rate of transplant-related mortality (TRM). In the present study we evaluate the outcome of MI patients undergoing an allogenic SCT after reduced intensity conditioning (RIC) regimens, and the impact of prognostic factors.
Design and methods:
Fifty two patients were transplanted in 26 Italian centres between 1998 and 2006. We analyzed the influence of patient and disease clinical features before SCT and of transplant procedures on TRM and overall survival (OS) by means of univariate and multivariate analyses.
At SCT, median age was 52,5 years (32–68) and 89% of the patients had an intermediate or high Dupriez score. Conditioning regimens were based on fludarabine plus busulphan in 27% of patients, thiotepa plus cyclophosphamide in 46% and miscellaneous drug combinations in the other 27% of cases. Stem cells came from matched sibling donors for 75% of the patients and mismatched sibling or unrelated donors for the remaining 25%. The cumulative incidence of engraftment at day 90 after transplant was 83% (95% CI, 0.87–0.97). The estimated 1-year TRM was 30%. The estimated 3-year event-free-survival (EFS) and OS after hematopoietic SCT was 44% and 38% respectively. In multivariate analysis, an higher leukocyte count and circulating blasts in the peripheral blood before SCT significantly reduced EFS and OS respectively.
Interpretation and conclusions:
We conclude that the extension of the disease before transplantation based on the presence of circulating blasts and high leukocyte counts significantly affected the outcome after HSCT
PMCID: PMC3033132  PMID: 21415963

Results 1-4 (4)