Optical detection of acetyl phosphate and biogenic amines

Fluorescent probes for the determination of biologically relevant anions like acetate (Ac), and acetyl phosphate (AcP) were investigated. Two known probes for anions were screened for their spectral responses towards these target molecules. With the insights obtained, new luminescent probes based on ruthenium complexes were designed, synthesized, and characterized with respect to selectivity towards AcP in organic solvents and highly competitive aqueous solutions and response towards other biologically important anions. The determination of acetyl phosphate was successfully accomplished using the fluorogenic probe RuPDO. This complex contains two oxime groups that are activated in situ by the addition of Zn2+. The rapid and direct determination of acetyl phosphate was conducted in highly biocompatible aqueous solutions at neutral pH. The metal complex itself is almost non-fluorescent (excitation wavelength: 469 nm , emission wavelength: 610 nm). The intensity of emission undergoes ca. 30-fold enhancement upon reaction with AcP in low mM concentrations in HEPES buffer at pH 7.4. An incubation time of 60 min at 37 °C is required. Upon reaction with AcP, the probe shows a 30 nm-longwave shift of emission to 640 nm. Most importantly, and unlike in common methods for determination of AcP, the presence of millimolar inorganic phosphate only weakly reduces sensitivity. Successful determination of AcP in complex biological matrices like cell medium and bacterial growth medium (even in presence of lysed cells) was shown. Furthermore, a combination of RuPDO with the enzyme acetate kinase (AK) yielded a microplate assay for the determination of the important target acetate. The analyte was successfully determined with the developed assay in various real samples (even in strongly colored samples) with excellent compliance to the manufacturer information. The linear range of the method is from 100 µM to 2 mM. The LOD of the assay is comparable to commercially available enzymatic acetate kits. Though, the acetate assay developed is more robust and inexpensive due to the use of only one enzyme. Sensing strips for biogenic amines containing an amine-reactive dye are described in Chapter 6. These additionally contain a green fluorescent (amino-insensitive) reference dye incorporated in a hydrogel matrix that is deposited on a paper strip. Such strips enable rapid and direct determination of primary amines – especially biogenic amines (BA). A color change from blue to red occurs on addition of the test strips to a slightly alkaline sample containing primary amines in a concentration range from 0.01 to 10 mM within 15 min, thus enabling rapid qualitative and semi-quantitative evaluation. The color shift is accompanied by a strong increase of the fluorescence intensity of the dye, with a peak at 620 nm after photo-excitation at 505 nm with LEDs. A home-built setup was used for quantitative readout of the strips containing high-power 505-nm LEDs in a black box and a digital camera. The strips are photographed and the digital color information stored in the camera is extracted via a red-green-blue (RGB) readout. By referencing the red channel to the green channel, a quantitative signal is obtained that was used to create pseudo-color pictures of the sensor spots and for calculation of calibration plots. Finally, the sensing system was also successfully applied to the monitoring of the spoilage of different kinds of meat

Predictors of Surgery in Newly Diagnosed Pediatric Crohn's Disease Patients

Objectives: To assess whether small bowel imaging conducted at the time of diagnosis could be used as a predictor of small bowel surgical intervention in a pediatric Crohn's disease patient population. Methods: A retrospective analysis of small bowel imaging within 30 days of diagnosis of pediatric Crohn's disease was conducted. Patients were divide into two groups based on small bowel imaging: those with no or minor abnormalities (71%) and those with more extensive or obstructive abnormalities (29%). Medical records were reviewed for small bowel surgical intervention and clinic follow-up visits. Results: 232 patients were included in the study group (average age at diagnosis 11.7 years). Twenty-seven patients (12%) underwent small bowel surgical intervention. The relative risk for small bowel surgical intervention was 2.91 in the group with more extensive imaging abnormalities. The majority of increased surgical risk occurred in the first year after diagnosis, when the normal-minor group had a 2% surgical risk and the more abnormal group had a 17% surgical risk. Both groups had a 2-3% surgical risk per year after the first year. Conclusions: Small bowel imaging at the time of diagnosis in pediatric Crohn's disease can help predict the risk of small bowel surgical intervention, and should be recommended for all newly diagnosed patients. Nearly one-third of our cohort underwent small bowel surgical intervention through eight years of follow-up. Surgical complications of Crohn's disease often occur in the small bowel, and counseling families about surgical risk is an integral part of pediatric Crohn's disease management

Deploying the WTO Agreement on Government Procurement (GPA) to Enhance Sustainability and Accelerate Climate Change Mitigation

Mitigating climate change and promoting sustainability are defining challenges of our time. Public procurement has a vital role to play in responding to the current crises. This article makes the case that the World Trade Organization’s (WTO) Agreement on Government Procurement (GPA), and specifically the Work Programme on Sustainable Procurement that has been initiated pursuant to the Agreement, can serve as important instruments to promote sustainable approaches to public procurement internationally, consistent with the goals of climate change mitigation. The Work Programme, which was established at the time of the GPA’s modernization in 2012 and on which important work has already been done but which has recently been relatively dormant, mandates the Organization’s Committee on Government Procurement to study, inter alia, “the ways in which sustainable procurement can be practiced in a manner consistent with Parties’ international trade obligations ”and to prepare a report that sets out best practices concerning relevant measures and polices. This provides an essential and attractive platform for responding to the crisis. The article sets out important related background, including with respect to: (i) a “change of mindset” with respect to environmental sustainability which is already embodied in the amended GPA text adopted in 2012; (ii) existing GPA provisions that provide windows of opportunity for the advancing of related objectives; and (iii) importantly, ongoing developments in key GPA Parties and at the international level that both: (a) point the way toward meaningful change; and (b) suggest, in our view, a need for a modest degree of international coordination to avoid conflict and ensure continuing market openness. These developments portend a rich agenda of possibilities for further discussions in the WTO Work Programme

Anthroposophic perspectives in primary care

A core challenge of contemporary medicine is to integrate the technological successes of biomedical science with a comprehensive under-standing of the physical, psychosocial, ecological, and spiritual dimensions of health and illness. Toward this end, bridges are being created between conventional medicine and alternative systems of healing which reflect a holistic model of the human being. Even when both conventional and complementary approaches are used side-by-side in the same patient, they remain separate in their basic assumptions and goals. Today\u27s mechanistic disease model is cut off from such notions as life-energy, consciousness, and spirituality, so integral to many alternative paradigms. Anthroposophically Extended Medicine (AEM) is a comprehensive healing system that successfully integrates biomedicine with a more complete understanding of human reality. Originating in Europe at the beginning of the 20th century, AEM has its roots in the Western, scientific worldview. By expanding this worldview, anthroposophy offers the clinician new possibilities for scientific investigation; it also creates bridges to the wisdom of older healing traditions of both East and West

Altered STAT4 isoform expression in patients with inflammatory bowel disease.

BACKGROUND & AIMS: Crohn’s disease (CD) and ulcerative colitis (UC) are major forms of inflammatory bowel disease (IBD) and pathogenesis involves a complex interplay between genetic, environmental and immunological factors. We evaluated isoform expression of the IL-12-activated transcription factor STAT4 in children with CD and UC. METHODS: We performed a study where we collected biopsy samples from both newly diagnosed CD and UC patients. We further collected blood samples from newly diagnosed CD and UC patients as well as patients who had a flare-up after being in clinical remission, and examined the ratios of STAT4β/STAT4α mRNA. In addition to STAT4 isoforms we measured the expression of the cytokines TNFα, IFNγ, GM-CSF and IL-17 using PCR of biopsy samples and multiplex analysis of patient serum samples. RESULTS: Ratios of STAT4β/STAT4α were increased in specific GI tract segments in both CD and UC patients that correlate with location and severity of inflammation. In contrast, we did not observe changes in STAT4β/STAT4α ratios in biopsy specimens from eosinophilic esophagitis patients. We also observed increased STAT4β/STAT4α ratios in the peripheral blood mononuclear cells of UC and CD patients, compared to healthy controls. Ratios were normalized after patient treatment with steroids. CONCLUSIONS: Collectively, these data indicate that STAT4 isoforms could be an important non-invasive biomarker in the diagnosis and treatment of IBD, and that expression of these isoforms might provide further insight into the pathogenesis of IBD

Luminescent ruthenium probe for the determination of acetyl phosphate in complex biological matrices

A new optical sensing microplate was developed for rapid screening for the presence of biogenic amines (BAs) in seafood samples with high sensitivity. The deposition of a sensing spot (containing a chameleon dye (Py-1) in a polymeric cocktail) on the bottom of the wells of a standard microplate renders the plate a new sensing tool for a rapid and parallel detection of up to 96 (real) samples. This sensing microplate enables (1) a semi-quantitative readout of analyte concentration by eye-vision, (2) a rapid fluorescence readout of 96 samples with standard instrumentation in less than two minutes (unlike chromatographic and electrophoretic methods), (3) a statistically robust data evaluation (with 8–12 replicates) and (4) a rapid parallel sample preparation with standard 8 or 12-channel micropipettes. On reaction with biogenic amines, the dye shows a significant visible color change from blue over green to red color. The appearance of red color favorably coincides with the concentration of BAs that can induce symptoms of poisoning. The linear ranges of fluorescence calibration data for six biogenic amines cover the clinical toxicological relevant range of BAs that is too low to be detected by the human nose. The LODs range from 0.16 to 0.56 μg mL−1, with correlation coefficients (r2) between 0.985 and 0.999. Finally, the evolution of spoilage of four fish samples (monitored by determination of their BA status) and the increase of their total amine content were found to agree well with previous data on time-dependent evolution of BAs in fish

The effect of exposure to biomass smoke on respiratory symptoms in adult rural and urban Nepalese populations

Peer reviewedPublisher PD

Mapping and sensor fusion for an autonomous vehicle

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.Includes bibliographical references (leaves 81-82).by Steve J. Steiner.M.Eng

Biometric Data Comparison Between Lewis and Sprague Dawley Rats

Introduction: Pressure mapping systems are often used for indirect assessment of kinematic gait parameter differences after repair of critical peripheral nerve defects in small animal models. However, there does not appear to be any literature that studies the differences in normal gait pattern of Sprague Dawley rats compared to Lewis rats using a Tekscan VH4 pressure mat system. The purpose of this study is to assess the gait profile of Lewis and Sprague Dawley rats generated by Tekscan\u27s VH4 system to detect similarities and/or differences in gait parameters involving both force and temporal variables. Materials and Methods: The gait profile of 14 Lewis and 14 Sprague Dawley rats was recorded using a Tekscan VH4 pressure map system with two successful walks per animal and gait parameter data was normalized for mean variance between the two rodent strains. Results: The results showed that temporal and normalized force parameters were not significantly different between the two types of rats. Maximum force, contact area, stride length, and adjusted pressure variables were significantly different between the two strains, likely attributed to the body size and weight differential between the strains. Variation in some of these parameters were considered due to differences in overall body size between the two strains, variations in gait kinematics between individual rodent subjects, and the limitations of the current experimental design. Conclusion: For future in vivo models, either Sprague Dawley or Lewis rat strains would be acceptable animal models when comparing base-line gait profiles using the Tekscan VH4 pressure map system when assessing critical defect repairs of peripheral nerves