747 research outputs found
NIR camera for early detection of diabetic ulcers
The purpose of this Creative Inquiry is to test whether near-infrared (NIR) imaging devices can detect areas of skin at risk for ulceration in diabetic patients. Venous blood accumulation, or high levels of deoxygenated blood within a tissue, can indicate poor blood circulation and increased risk of ulceration. Here we propose to detect venous blood in tissues using differences in optical spectra of oxygenated vs. deoxygenated blood in NIR region. We previously designed and built a prototype scanner with three integrated NIR light sources that is being tested at MUSC. Our current work is focused on testing of improved NIR illumination systems and improved NIR imaging device, and our second prototype that uses a more sensitive Raspberry Pi-controlled camera and advanced NIR light sources will provide significantly improved image quality. Upon success, the ultimate goal of this project is to manufacture a cheap, portable NIR camera for skin self-monitoring by diabetic patients
Macro-AFM model
An Atomic Force Microscope (AFM) is an important tool in modern nanoscience, capable of producing surface maps at resolutions below 1 nanometer, which is impossible for other methods. Despite AFM\u27s often use, it is often difficult for students to understand their work because all measurement processes take place at micro- and nano-scale. The goal of this project is to create a macro scale model, which will serve as an educational tool to introduce the principles behind AFM to undergraduate and high school students. Currently, a fully automatic microprocessor-controlled surface scanning block has been built and successfully tested with a scan area of ca. one square foot. Continued work includes designing and building of a topography measurement block that will work on the same principle as a real AFM does at nano-level. We expect that macro AFM building an image using AFM techniques will empower instructors to show the concepts, and to spark interest of potential students in Bioengineering
When the Earth trembles in the americas: the experience of haiti and chile 2010.
The response of the nephrological community to the Haiti and Chile earthquakes which occurred in the first months of 2010 is described. In Haiti, renal support was organized by the Renal Disaster Relief Task Force (RDRTF) of the International Society of Nephrology (ISN) in close collaboration with Médecins Sans Frontières (MSF), and covered both patients with acute kidney injury (AKI) and patients with chronic kidney disease (CKD). The majority of AKI patients (19/27) suffered from crush syndrome and recovered their kidney function. The remaining 8 patients with AKI showed acute-to-chronic renal failure with very low recovery rates. The intervention of the RDRTF-ISN involved 25 volunteers of 9 nationalities, lasted exactly 2 months, and was characterized by major organizational difficulties and problems to create awareness among other rescue teams regarding the availability of dialysis possibilities. Part of the Haitian patients with AKI reached the Dominican Republic (DR) and received their therapy there. The nephrological community in the DR was able to cope with this extra patient load. In both Haiti and the DR, dialysis treatment was able to be prevented in at least 40 patients by screening and adequate fluid administration. Since laboratory facilities were destroyed in Port-au-Prince and were thus lacking during the first weeks of the intervention, the use from the very beginning on of a point-of-care device (i-STAT®) was very efficient for the detection of aberrant kidney function and electrolyte parameters. In Chile, nephrological problems were essentially related to difficulties delivering dialysis treatment to CKD patients, due to the damage to several units. This necessitated the reallocation of patients and the adaptation of their schedules. The problems could be handled by the local nephrologists. These observations illustrate that local and international preparedness might be life-saving if renal problems occur in earthquake circumstances
T cells loaded with magnetic nanoparticles are retained in peripheral lymph nodes by the application of a magnetic field
T lymphocytes are highly dynamic elements of the immune system with a tightly regulated migration. T cell-based transfer therapies are promising therapeutic approaches which in vivo efficacy is often limited by the small proportion of administered cells that reaches the region of interest. Manipulating T cell localisation to improve specific targeting will increase the effectiveness of these therapies. Nanotechnology has been successfully used for localized release of drugs and biomolecules. In particular, magnetic nanoparticles (MNPs) loaded with biomolecules can be specifically targeted to a location by an external magnetic field (EMF). The present work studies whether MNP-loaded T cells could be targeted and retained in vitro and in vivo at a site of interest with an EMF.Results: T cells were unable to internalize the different MNPs used in this study, which remained in close association with the cell membrane. T cells loaded with an appropriate MNP concentration were attracted to an EMF and retained in an in vitro capillary flow-system. MNP-loaded T cells were also magnetically retained in the lymph nodes after adoptive transfer in in vivo models. This enhanced in vivo retention was in part due to the EMF application and to a reduced circulating cell speed within the organ. This combined use of MNPs and EMFs did not alter T cell viability or function.Conclusions: These studies reveal a promising approach to favour cell retention that could be implemented to improve cell- based therapy
Enhanced contrast detection of subsurface defects by pulsed infrared thermography based on the fourth order statistic moment, kurtosis
The automatic detection of subsurface defects has become a desired goal in the application of non-destructive testing and evaluation techniques. In this paper, an algorithm based on the fourth order standardised statistic moment, i.e. kurtosis, is proposed for detection and/or characterization of subsurface defects having a thermal diffusivity either higher or lower than the host material. The analysis of thermographic data for the detection of defects can be reduced to the temporal statistics of the thermographic sequence. The final result provided by this algorithm is an image showing the different defects without the necessity of establishing other evaluating parameters such as the delayed time of the first image or the acquisition frequency in the analysis, which are required in other processing techniques. All the information is contained in a single image allowing to discriminate between the defect types (high o low thermal diffusivity). Synthetic data from Thermocalcà ® and experimental works using a PlexiglasTM specimen were performed showing good agreement. Processed results using synthetic and experimental data with other methods used in the field of thermography for defect detection and/or characterization are provided as well for comparison
Impact of circulating bacterial DNA in long-term glucose homeostasis in non-diabetic patients with HIV infection: cohort study
In HIV-infected patients, the damage in the gut mucosal immune system is not completely restored after antiretroviral therapy (ART). It results in microbial translocation, which could influence the immune and inflammatory response. We aimed at investigating the long-term impact of bacterial-DNA translocation (bactDNA) on glucose homeostasis in an HIV population. This was a cohort study in HIV-infected patients
whereby inclusion criteria were: patients with age >18 years, ART-naïve or on effective ART (<50 HIV-1 RNA copies/mL) and without diabetes or chronic hepatitis C. Primary outcome was the change in HbA1c (%). Explanatory variables at baseline were: bactDNA (qualitatively detected in blood samples by PCR [broad-range PCR] and gene 16SrRNA - prokaryote), ART exposure, HOMA-R and a dynamic test HOMACIGMA
[continuous infusion of glucose with model assessment], hepatic steatosis (hepatic triglyceride content -
1H-MRS), visceral fat / subcutaneous ratio and inflammatory markers. Fifty-four men (age 43.2 ± 8.3 years, BMI
24.9 ± 3 kg/m2, mean duration of HIV infection of 8.1 ± 5.3 years) were included. Baseline HbA1c was 4.4 ± 0.4% and baseline presence of BactDNA in six patients. After 8.5 ± 0.5 years of follow-up, change in HbA1c was
1.5 ± 0.47% in patients with BactDNA vs 0.87 ± 0.3% in the rest of the sample p < 0.001. The change in Hba1c was also influenced by protease inhibitors exposure, but not by baseline indices of insulin resistance, body composition, hepatic steatosis, inflammatory markers or anthropometric changes. In non-diabetic patients with HIV infection, baseline bacterial translocation and PI exposure time were the only factors associated with long-term impaired glucose homeostasis
Obtención de injerto óseo de cresta iliaca anterior bajo sedación intravenosa para reconstrucción de defecto alveolar. Reporte de un caso.
Los injertos de cresta iliaca suelen ser difíciles de obtener en la consulta, debido a su morbilidad y complicaciones por lo que su obtención se puede decir que se encuentra restringido a centros hospitalarios.El objetivo de este artículo es mostrar una nueva opción para la recolección de este injerto mediante sedación intravenosa en el consultorio, sin comprometer los cuidados del paciente. Se presenta en este artículo una paciente de 16 años de edad con antecedente de trauma facial a la cual se le realizo injerto de cresta iliaca para reconstrucción de reborde alveolar anterior maxilar bajo sedación intravenosa, presentado una evolución favorable, controlando de manera adecuada todos los riesgos y comorbilidades, siendo bien aceptado y tolerado por el paciente
Estudio comparativo de las propiedades fisicoquímicas de miel natural y miel sometida a proceso comercial
La miel es un fluido dulce y viscoso producido por las abejas a partir del néctar de las fl ores o de secreciones de partes vivas de plantas o de excreciones de insectos chupadores de plantas. Las abejas lo recogen, transforman y combinan con la enzima invertasa que contiene la saliva de las abejas y lo almacenan en los panales donde madura, su composición depende de dos factores principales; del néctar o néctares, donde va a infl uir la especie o conglomerado de especies de plantas que producen el néctar y de factores externos, como la temperatura, almacenamiento y buenas prácticas de manufactura por parte del apicultor para poder realizar la cosecha. El objetivo del proyecto fue realizar un análisis comparativo de las propiedades fi sicoquímicas en dos tipos de miel, aquella que es tomada del panal de abeja “miel natural”, que no ha sido sometida a tratamiento y la que se encuentra a nivel comercial. La selección de estas mieles respondió al interés de conocer la calidad de las mismas. Para ello se determinó contenido de cenizas, hidroximetilfurfural, °Brix, porcentaje de humedad y grado de acidez. En base a los resultados obtenidos se logro identificar que la miel natural se encuentra dentro de los estándares de la Norma Técnica Colombiana 1273 (NTC, 1273) y la miel comercial, presenta rangos superiores a lo establecido, puesto que los niveles de hidroximetilfurfural (HMF) y acidez, están directamente relacionados con elevadas temperaturas y tiempos de almacenamiento prolongado
Una sierra y su gente : Xico : Veracruz
Les trois auteurs expriment, chacun avec émotion, la vie quotidienne dans le village de Xicochimalco de Santa Maria Magdalena. Les textes sont illustrés de très belles photographies en noir et blanc
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