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Biomedical subjects

C P Martin

Publications and source records attributed to C P Martin.

12 recordsLinked to original sources
PubMed2004

Iron wheels on silicon: wetting behavior and electronic structure of adsorbed organostannoxane clusters.

Atomic force microscopy and synchrotron radiation (SR) spectroscopy have been used to study the wetting behavior and electronic structure of thin films of a novel organometallic cluster--[BuSn(O)OC(O)Fc]6 ("Fc" = ferrocenyl)--on silicon substrates. This cluster comprises six ferrocene units connected to a stannoxane central core--"an iron wheel on a tin drum" (V. Chandrasekhar; et al. Angew. Chem., Int. Ed. 2000, 39, 1833). Thin films spin-cast onto native oxide-terminated silicon readily dewet the substrate. We have utilized advanced image analysis techniques based on Minkowski functionals to provide a detailed quantitative analysis of the morphology of the stannoxane overlayers. This analysis shows that the dewetting patterns are rather far removed from those expected to arise from a simple Poisson distribution of centers, and we discuss the implications of this finding in terms of nucleated and spinodal dewetting. Variations in both the surface roughness and the in-plane correlation length have been followed as a function of annealing time to probe the surface dewetting dynamics. SR valence band photoemission illustrates that the highest occupied molecular orbital (HOMO) of the cluster is found 2 eV below the Fermi level. Fe 2p --> 3d and Sn 3d --> 5p resonant photoemission spectroscopy have been used to enhance the cross sections of the partial density of states associated with the Fe and Sn atoms. Sn atoms make a large contribution to the HOMO of the cluster, whereas the Fe atoms are associated with an electronic environment seemingly very similar to that in the "parent" ferrocene molecule.

Journal Article↗
PubMed2004

The effect of tibial implant size on post-operative alignment following medial unicompartmental knee replacement.

We have retrospectively reviewed a consecutive series of 71 medial unicompartmental knee replacements in 56 patients performed between 1991 and 1996 by a single surgeon. The aim of this study was to quantify the amount of correction in the tibiofemoral angle, which is achievable with each thickness of polyethylene tibial insert. Our results have shown that the amount of correction which can be expected with an 8 mm, 10 mm, 12 mm and 14 mm insert are 5.3 degrees, 4.8 degrees, 6.6 degrees and 9.5 degrees, respectively. These results will act as a useful reference for surgeons who perform this procedure.

Aged↗
PubMed2001

Lymphangiogenesis and lymphangiodysplasia: from molecular to clinical lymphology.

The lymph vascular system parallels the blood vasculature and as one of its key functions returns liquid and solutes to the bloodstream, including macromolecules that have escaped from blood capillaries and entered the interstitium. In conjunction with interspersed lymph nodes and lymphoid organs, the lymphatic vasculature also acts as a conduit for trafficking immune cell populations. Echoing the explosion of knowledge about blood vessel angiogenesis (properly termed "hemangiogenesis"), the past two decades have also witnessed a series of significant, yet less-noticed discoveries bearing on "lymphangiogenesis," along with delineation of the spectrum of lymphedema-angiodysplasia syndromes. Failure of lymph transport promotes a brawny proteinaceous edema of the affected limb, organ, or serous space that is disfiguring, disabling, and on occasion even life-threatening. Key members of the vascular endothelial growth factor (VEGF) and angiopoietin families of vascular growth factors (and their corresponding tyrosine kinase endothelial receptors) have been identified which preferentially influence lymphatic growth and, when manipulated in genetically engineered murine models, produce aberrant "lymphatic phenotypes." Moreover, mutations in VEGF receptor and forkhead family developmental genes have now been linked and implicated in the pathogenesis of two familial lymphedema-angiodysplasia syndromes. Thus, recent advances in "molecular lymphology" are elucidating the poorly understood development, physiology, and pathophysiology of the neglected lymphatic vasculature. In combination with fresh insights and refined tools in "clinical lymphology," these advances should lead not only to earlier detection and more rational classification of lymphatic disease but also to better therapeutic approaches, including designer drugs for lymphangiostimulation and lymphangioinhibition and gene therapy to modulate lymphatic growth.

Angiodysplasia↗
PubMedDate not supplied

Incidence, prevalence, and mortality of diabetes mellitus in Wadena, Marshall, and Grand Rapids, Minnesota: the Three-City Study.

The Minnesota Department of Health (MDH) in concert with the Centers for Disease Control (CDC) conducted population-based studies of diabetes mellitus in three Minnesota communities. The use of hospital and clinic records alone for case ascertainment purposes would have missed 16% of study-eligible diabetic individuals. Thus, studies that use only hospital or clinic records may present a biased view of the natural history of diabetes. Physician-defined diabetes without additional diagnostic review yielded a prevalence of 1.6% (age standardized to the 1970 US Caucasian population). Diabetes incidence was 117 per 100,000 (age standardized to the same population). These results compare well with those of a Mayo Clinic population-based study in Rochester, Minnesota, and indicate the utility of physician-defined diabetes as an epidemiologic case definition. Despite differences in population size and structure as well as different medical care systems, diabetes incidence, prevalence, and mortality in these communities was remarkably similar.

Adolescent↗