217 research outputs found

    Stabilité d'une structure spatiale et compromis d'une analyse statistique multi-tableaux : application à la physico-chimie d'un lac réservoir

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    10 paramètres physico-chimiques sont mesurés en surface dans 10 stations à 12 dates sur le lac réservoir de la Sorme (Saône-et-Loire). L'article montre comment une analyse multitableaux peut caractériser la structure spatiale et préciser sa stabilité. Les notions d'interstructure et de compromis sont accessibles par une procédure simple et efficace.This paper is based on the observation that three-dimensional data matrices (sites x times x variables) often used in limnological investigations require statistical analyses fitted to experimental objectives. Many apparently different statistical tools (3-mode PCA of TUCKER, 1964; KROONENBERG, 1983; projection of variables WILLIAMS and STEPHENSON, 1973; DOLEDEC and CHESSEL, 1987) may be useful to clarify limnological problems such as : 1) the temporal variability of a pattern (elimination of spatial heterogenity) : 2) the spatial structure of a pattern (elimination of temporal effects, mapping of an average situation) : 3) the temporal variability of Lake stratification (stability, modification or inversion) : 4) the spatial structure of temporal variability, and 5) the between variables typology of a spatial and temporal structure. Our methodological approach allowed us to assess the temporal stability of the spatial structure of the Lake waters (question 3) using a multitable analysis known as triadic analysis (THIOULOUSE and CHESSEL, 1987).As part of the limnological study of a reservoir Lake (Sorme reservoir Lake, Saône-et-Loire, France) 10 commonly used physical and chemical variables were studied from July 1980 to October 1931. During this period, 12 water samples were taken near the surface at each of the 10 stations scattered along the Sorme Lake (see figure 1). Main morphometric features of the Sorme Lake are : 1) a surface area equal to 230 ha, 2) a 25 km long perimeter and 3) a volume of 9.5 106 m3 with a maximum depth of 13 meters upstream of the dam and an average depth of about 4 meters. Seasonal tidal range was only a few meters.Only 2 of the 3 concepts of triadic analysis stated by THIOULOUSE and CHESSEL, 1987 are developed here : 1) for each of the 12 tables (stations x variables) coming from the 12 sampling dates, data are first centered (elimination of mean) and standardized (division by standard deviation) (see figure 2). The resulting table Y called interstructure matrix, i.e. interstructure between each of the sampling dates matrix, is organized to have sampling dates as columns and the ten physical and chemical variables at each station successively as fines. Principal Component Analysis (PCA on the variance-covariance matrix) is then applied to the interstructure matrix. In our case it is a one-dimensional matrix, i.e. according to physical and chemical variables, there is only one spatial structure common to each sampling date (figure 3 and 2) compromise matrix are associated with the successive PCA factors of the interstructure (figure 4). According to the previous remark, only the first factor is considered. Data are reorganized to have physical and chemical variables as columns, and stations as fines. This last table defines a compromise matrix labelled Z. The mapping of the numerical values of matrix Z renders a ten-dimensional description of the permanent spatial structure (figure 5). To summarize the multivariate description, matrix Z is processed with a PCA on the variance-covariance matrix producing a three-dimensional compromise (figure 6).The interpretation of the compromise table by mapping the factorial scores of the PCA leads to a functional scheme of the reservoir Lake waters distinguishing five sectors (see figure 7) as a function of water depth, influence of tidal range, influence of tributaries and of the Sorme River. 3 stations are periodically isolated from the reservoir and produce 3 sectors with lower pH and temperature values and higher concentrations in ammonia and sulphate according to the influence of tributaries. The 4th sector is associated with the former submerged valley, i.e. main channel of the Sorme River prior to the dam closure, and demonstrated an ionic gradient concerning mainly nitrate and chloride-concentrations. The 5th sector, opposed to the latter, consists in the deeper area of the Sorme Lake which reveals rather homogeneous waters near the surface

    Prevention of Dermatologic Side Effects of Bimatoprost 0.03% Topical Therapy

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    PURPOSE: To investigate the efficacy of reducing the drop-skin contact to prevent dermatologic side effects of bimatoprost 0.03% topical therapy. DESIGN: Prospective, randomized, single-blinded, internally controlled study. METHODS: Enrolled subjects started bimatoprost 0.03% therapy once at night in both eyes and were instructed to wipe selectively only one eye (eye 1) with an adsorbent pad during and after drops administration for four months. The fellow eye acted as the internal control. Eyelash growth, regional skin hypertrichosis, and pigmentation on the periocular skin were assessed at baseline and during the four months of follow-up. RESULTS: A lower incidence of eyelash growth and skin pigmentation in the inferonasal pericanthal region were observed in eye 1. The incidence of pigmentation in the inferotemporal skin region and skin hypertrichosis were similar in the two eyes. CONCLUSION: The reduction of the drop,skin contact affects the regional incidence and the extent of dermatologic skin changes that are related to bimatoprost 0.03% topical therapy

    Comparison of Travoprost and Bimatoprost plus timolol fixed combinations in open-angle glaucoma patients previously treated with latanoprost plus timolol fixed combination

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    To compare the ocular hypotensive effect of bimatoprost plus timolol and travoprost plus timolol fixed combinations in glaucoma patients whose disease was controlled but had not reached their target intraocular pressure (IOP) with the fixed combination of latanoprost plus timolol

    Scanning electron microscopy study on mandibular human bone and immunofluorescence study on oral mucosa in patients treated with bisphosphonates

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    Bisphosphonates are stable analogues of pyrophosphate with a P-C-P structure and 2 side chains attached to the carbon atom. Intravenous bisphosphonates are primarily used and effective in the management of cancer-related conditions in the context of solid tumors, such as breast cancer, prostate cancer, and lung cancer. Moreover bisphosphonates are subministrated to patients with metabolic bone diseases such as osteoporosis and Paget disease. Bisphosphonate-associated osteonecrosis of the jaws (BONJ) is a really complication of intravenous bisphosphonate therapy in patients with cancer. It is common knowledge that the jaws have a greater blood supply than other bones and a fasterbone turnover rate, related both to their daily activity and presence of teeth which mandates daily bone remodeling around the periodontal ligament; moreover bisphosphonates toxicity to epithelial cells has been well documented. On this basis, the aim of this study is to evaluate the pathological changes of the mandibular bone and oral mucosa in patients treated with bisphosphonates, during osteoporosis treatment and during chemotherapy from solid cancer. In details we have analyzed, by immunohistochemical and scanning electron microscopic methods, intrasurgical biopsy of mandibular bone and of gingival mucosa in patients treated with bisphosphonates both intravenous and oral via after 24 and 36 months from assumption of drugs. Our results show in all patients great area demineralization bone mixed to normal bone, moreover in the demineralization bone it’s possible to observe numerous micro lacunae. In the correspondence samples of gingival epithelium we observe important lesions of histological structure and the disappearance of protein adhesion system cells to cells and cells to matrix. On this basis it is intriguing to speculate that the adverse effects of BP on oral epithelium may play a critical role in the initiation of BONJ an “outside-in” hypothesis

    Two Different Therapeutic Approaches for SARS-CoV-2 in hiPSCs-Derived Lung Organoids

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    The global health emergency for SARS-CoV-2 (COVID-19) created an urgent need to develop new treatments and therapeutic drugs. In this study, we tested, for the first time on human cells, a new tetravalent neutralizing antibody (15033-7) targeting Spike protein and a synthetic peptide homologous to dipeptidyl peptidase-4 (DPP4) receptor on host cells. Both could represent powerful immunotherapeutic candidates for COVID-19 treatment. The infection begins in the proximal airways, namely the alveolar type 2 (AT2) cells of the distal lung, which express both ACE2 and DPP4 receptors. Thus, to evaluate the efficacy of both approaches, we developed three-dimensional (3D) complex lung organoid structures (hLORGs) derived from human-induced pluripotent stem cells (iPSCs) and resembling the in vivo organ. Afterward, hLORGs were infected by different SARS-CoV-2 S pseudovirus variants and treated by the Ab15033-7 or DPP4 peptide. Using both approaches, we observed a significant reduction of viral entry and a modulation of the expression of genes implicated in innate immunity and inflammatory response. These data demonstrate the efficacy of such approaches in strongly reducing the infection efficiency in vitro and, importantly, provide proof-of-principle evidence that hiPSC-derived hLORGs represent an ideal in vitro system for testing both therapeutic and preventive modalities against COVID-19

    Deep sternal wound infections: Evidence for prevention, treatment, and reconstructive surgery

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    Median sternotomy is the most popular approach in cardiac surgery. Post-sternotomy wound complications are rare, but the occurrence of a deep sternal wound infection (DSWI) is a catastrophic event associated with higher morbidity and mortality, longer hospital stays, and increased costs. A literature review was performed by searching PubMed from January 1996 to August 2017 according to the guidelines in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The following keywords were used in various combinations: DSWI, post-sternotomy complication, and sternal reconstruction. Thirty-nine papers were included in our qualitative analysis, in which each aspect of the DSWI-related care process was analyzed and compared to the actual standard of care. Plastic surgeons are often involved too late in such clinical scenarios, when previous empirical treatments have failed and a definitive reconstruction is needed. The aim of this comprehensive review was to create an up-to-date operative flowchart to prevent and properly treat sternal wound infection complications after median sternotomy

    Carney-Complex: Multiple resections of recurrent cardiac myxoma

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    We report a case of a female patient who was operated at the third relapse of an atrial myxoma caused by Carney complex. The difficult operation was performed without any complications despite extensive adhesions caused by the previous operations. The further inpatient course went without complications and the patient was discharged to the consecutive treatment on the 9th postoperative day. The echocardiographic finding postoperative showed no abnormalities
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