135 research outputs found
Extended abdominoperineal resection in women: the barbadian experience
BACKGROUND AND OBJECTIVES: We report our results of a selective approach to primary direct appositional vaginal repair versus transverse rectus abdominis flap repair (TRAM) in patients with extensive rectal/anal cancer or in cases with primary cancer of cervix, vagina or vulva involving the anal canal and anal sphincters. METHODS: Eighteen female patients (mean age: 62.9 years; range: 44–81 years) with a median follow-up of 14 months (range: 2–36 months) undergoing extended abdominoperineal reconstruction with total mesorectal excision between May 2002 and September 2005, were studied. RESULTS: Twelve patients underwent an extended abdominoperineal resection with hysterectomy and vaginectomy, with 6 patients undergoing primary TRAM flap reconstruction following pelvic exenteration. Exenterative procedures were performed in 2 cases of primary vaginal cancer, following Wertheim hysterectomy for carcinoma of the cervix with recurrence after radiation and in 2 further cases of anal cancer with extensive pelvic recurrence after primary chemoradiation. Fifteen cases are alive on follow-up with no evidence of disease; 2 patients who had recurrent carcinoma of the cervix and who underwent TRAM flap reconstruction, have recurrent disease after 5 and 6 months of follow-up, respectively. DISCUSSION: Our experience shows that careful primary closure of an extended abdominoperineal resection wound is effective and safe. Our one case of wound breakdown after primary repair underwent external beam and intracavitary irradiation primarily with wound breakdown of a primary repair followed by a delayed pedicled graciloplasty. TRAM flap reconstruction has been reserved in our unit for patients undergoing total pelvic extenteration. In general, we would recommend the use of TRAM flap reconstruction in younger sexually active patients where there has been external irradiation combined with brachytherapy
The Skeletal Organic Matrix from Mediterranean Coral Balanophyllia europaea Influences Calcium Carbonate Precipitation
Scleractinian coral skeletons are made mainly of calcium carbonate in the form of aragonite. The mineral deposition occurs in a biological confined environment, but it is still a theme of discussion to what extent the calcification occurs under biological or environmental control. Hence, the shape, size and organization of skeletal crystals from the cellular level through the colony architecture, were attributed to factors as diverse as mineral supersaturation levels and organic mediation of crystal growth. The skeleton contains an intra-skeletal organic matrix (OM) of which only the water soluble component was chemically and physically characterized. In this work that OM from the skeleton of the Balanophyllia europaea, a solitary scleractinian coral endemic to the Mediterranean Sea, is studied in vitro with the aim of understanding its role in the mineralization of calcium carbonate. Mineralization of calcium carbonate was conducted by overgrowth experiments on coral skeleton and in calcium chloride solutions containing different ratios of water soluble and/or insoluble OM and of magnesium ions. The precipitates were characterized by diffractometric, spectroscopic and microscopic techniques. The results showed that both soluble and insoluble OM components influence calcium carbonate precipitation and that the effect is enhanced by their co-presence. The role of magnesium ions is also affected by the presence of the OM components. Thus, in vitro, OM influences calcium carbonate crystal morphology, aggregation and polymorphism as a function of its composition and of the content of magnesium ions in the precipitation media. This research, although does not resolve the controversy between environmental or biological control on the deposition of calcium carbonate in corals, sheds a light on the role of OM, which appears mediated by the presence of magnesium ions
A re-examination of otoconia from the Shaker mouse
We have studied saccular and utricular otoconia from Shaker-1 and Shaker-2 mice by X-ray diffraction and scanning electron microscopy. In contrast to previous reports, we found that the crystals were composed of calcite rather than poly crystalline hydroxylapatite. These crystals were indistinguishable mineralogically and morphologically from normal mouse otoconia. The reported occurrence of hydroxylapatite otoconia in the Shaker mouse is probably false.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47271/1/405_2004_Article_BF00464412.pd
Structural Characterization and Biological Fluid Interaction of Sol−Gel-Derived Mg-Substituted Biphasic Calcium Phosphate Ceramics
Light quality and photoreactivation of plants and viruses
Visible light of different spectral regions was tested for its ability to reverse three effects of ultra-violet radiation, namely, injury ( glazing) of French bean leaves, increased resistance of French bean leaves to infection by the Rothamsted tobacco necrosis virus, and inactivation of potato virus X. The different spectral regions were obtained with colorimetric filters and the filtered and unfiltered light from fluorescent tubes; all three effects were reversed only by regions of wave-lengths shorter than 4700 angstrom. Thirty minutes of illumination at 300-380 f.c. gave substantial photoreactivation, but irradiated potato virus Chi did not become affected by visible light until 30 min. after tobacco leaves were inoculated
ULTRAVIOLET-RADIATION-ACCELERATED LEAF CHLOROSIS: PREVENTION OF CHLOROSIS BY REMOVAL OF EPIDERMIS OR BY FLOATING LEAF DISCS ON WATER
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