Citrulline as a marker of intestinal function and absorption in clinical settings: A systematic review and meta-analysis

Background: Citrulline has been described as a marker of intestinal function or absorption but evidence varies according to clinical settings. Objective: The objective of this article is to examine the evidence of plasma citrulline as a marker of intestinal function and absorption in various clinical settings. Methods: Studies were examined for p values, means and standard deviations, correlation coefficients or other metrics depicting the association of citrulline with intestinal function. A random effects model was used to produce a pooled estimate. A hierarchical summary receiver operating curve model was fitted for diagnostic accuracy measures. Results: Citrulline levels are correlated strongly with small bowel length in short bowel syndrome patients (r  = 0.67). Citrulline is strongly negatively correlated (r  = –0.56) with intestinal disease severity with regards to enteropathies (coeliac disease, tropical enteropathy, Crohn’s disease, mucositis, acute rejection in intestinal transplantation). Citrulline cut-off levels have an overall sensitivity and specificity of 80% and 84% respectively. Citrulline levels in untreated coeliac patients compared to controls were reduced by 10 µmol/l. Citrulline levels increase with gluten-free diet and with improvement of enteropathy. Citrulline is decreased in critical illness and sepsis. Conclusion: These findings allow us to advocate quite reasonably that citrulline is a marker of acute and chronic intestinal insufficiency

Photonic Physical Unclonable Functions: From the Concept to Fully Functional Device Operating in the Field

The scope of this paper is to demonstrate a fully working and compact photonic Physical Unclonable Function (PUF) device capable of operating in real life scenarios as an authentication mechanism and random number generator. For this purpose, an extensive experimental investigation of a Polymer Optical Fiber (POF) and a diffuser as PUF tokens is performed and the most significant properties are evaluated using the proper mathematical tools. Two different software algorithms, the Random Binary Method (RBM) and Singular Value Decomposition (SVD), were tested for optimized key extraction and error correction codes have been incorporated for enhancing key reproducibility. By taking into consideration the limitations and overall performance derived by the experimental evaluation of the system, the designing details towards the implementation of a miniaturized, energy efficient and low-cost device are extensively discussed. The performance of the final device is thoroughly evaluated, demonstrating a long-term stability of 1 week, an operating temperature range of 50C, an exponentially large pool of unique Challenge-Response Pairs (CRPs), recovery after power failure and capability of generating NIST compliant true random numbers

Amplitude Regeneration of Phase Encoded Signals using Injection Locking in Semiconductor Lasers

A phase preserving limiter based on injection locking in semiconductor lasers is experimentally investigated for 10Gb/s phase encoded signals. The proposed scheme exhibits significant amplitude noise squeezing in conjunction with extreme simplicity

Review of the literature and description of a case of sclerosing encapsulating peritonitis requiring home parenteral nutrition

We present a case of a 48 year old HIV patient, who had recurrent episodes of ascites since 2007. His history includes ischaemic heart disease, for which he was treated with atenolol from 2005 to 2007, and Type 2 diabetes; he was later started on propranolol 40  mg twice a day from 2007 for Didanosine-induced portal hypertension. Because of negative cultures and neutrophil count < 250 cells/μL, spontaneous bacterial peritonitis was excluded. However, some low grade-peritoneal irritation cannot be ruled out because his CRP varied from 24 to 258, during 2007 - 2009, without any other obvious inflammatory cause. He was finally diagnosed in July 2009 with sclerosing encapsulating peritonitis (SEP) based on clinical features of intestinal obstruction, histology and imaging, including computed tomography and magnetic resonance imaging. Propranolol was stopped in November 2009.  Because of the patient's severe intestinal obstruction, he was started on parenteral nutrition 2  L/day. Since then, his CRP has returned to normal levels and there is a great improvement of his clinical features. This case demonstrates beta-blockers as a potential cause of SEP, while the presence of some low-grade peritoneal inflammation leading to SEP is also very likely

Was citrulline first a laxative substance? The truth about modern citrulline and its isolation

Citrulline is a non-protein amino acid and is produced by the enterocytes of the small bowel. The isolation though of citrulline is generally ascribed to the 1930s. In the present article, we demonstrated that before 1930, there is was use of the term citrulline, signifying though a resin produced by Citrullus Colocynthis. This citrulline is different fomr modern citrulline. However, neither was modern citrulline isolated in 1930 but somewhat earlier. Reviewing the original manuscripts, Koga and Ohtake (1914) did indeed isolate citrulline for the first time and at least half a dozen other researchers cite their work. Even though their work didn’t lead to the determination of the structure and nature of citrulline, theirs was the first to isolate it. Our results have a certain historical and scientific significance and are discussed in extent

Temperature dependence of the Brewer global UV measurements

Spectral measurements of global UV irradiance recorded by Brewer spectrophotometers can be significantly affected by instrument-specific optical and mechanical features. Thus, proper corrections are needed in order to reduce the associated uncertainties to within acceptable levels. The present study aims to contribute to the reduction of uncertainties originating from changes in the Brewer internal temperature, which affect the performance of the optical and electronic parts, and subsequently the response of the instrument. Until now, measurements of the irradiance from various types of lamps at different temperatures have been used to characterize the instruments' temperature dependence. The use of 50 W lamps was found to induce errors in the characterization due to changes in the transmissivity of the Teflon diffuser as it warms up by the heat of the lamp. In contrast, the use of 200 or 1000 W lamps is considered more appropriate because they are positioned at longer distances from the diffuser so that warming is negligible. Temperature gradients inside the instrument can cause mechanical stresses which can affect the instrument's optical characteristics. Therefore, during the temperature-dependence characterization procedure warming or cooling must be slow enough to minimize these effects. In this study, results of the temperature characterization of eight different Brewer spectrophotometers operating in Greece, Finland, Germany and Spain are presented. It was found that the instruments' response changes differently in different temperature regions due to different responses of the diffusers' transmittance. The temperature correction factors derived for the Brewer spectrophotometers operating at Thessaloniki, Greece, and Sodankylä, Finland, were evaluated and were found to remove the temperature dependence of the instruments' sensitivity.This article is based upon work from COST Action ES1207 “A European Brewer Network (EUBREWNET)”, supported by COST (European Cooperation in Science and Technology) and from the ENV59-ATMOZ (“Traceability for atmospheric total column ozone”) Joint Research Programme (JRP)

Is Green Recovery Enough? Analysing the Impacts of Post-COVID-19 Economic Packages

Emissions pathways after COVID-19 will be shaped by how governments’ economic responses translate into infrastructure expansion, energy use, investment planning and societal changes. As a response to the COVID-19 crisis, most governments worldwide launched recovery packages aiming to boost their economies, support employment and enhance their competitiveness. Climate action is pledged to be embedded in most of these packages, but with sharp differences across countries. This paper provides novel evidence on the energy system and greenhouse gas (GHG) emissions implications of post-COVID-19 recovery packages by assessing the gap between pledged recovery packages and the actual investment needs of the energy transition to reach the Paris Agreement goals. Using two well-established Integrated Assessment Models (IAMs) and analysing various scenarios combining recovery packages and climate policies, we conclude that currently planned recovery from COVID-19 is not enough to enhance societal responses to climate urgency and that it should be significantly upscaled and prolonged to ensure compatibility with the Paris Agreement goal

Multicentre randomised controlled trial comparing standard and high resolution optical technologies in colorectal cancer screening.

Background and objectives: The UK bowel cancer screening programme (BCSP) has been established for the early detection of colorectal cancer offering colonoscopy to patients screened positive by faecal occult blood tests. In this multisite, prospective, randomised controlled trial, we aimed to compare the performance of Standard Definition Olympus Lucera (SD-OL) with Scope Guide and the High Definition Pentax HiLine (HD-PHL). Patients and methods: Subjects undergoing a colonoscopy as part of the UK National BCSP at four UK sites were randomised to an endoscopy list run using either SD-OL or HD-PHL. Primary endpoints were polyp and adenoma detection rate (PDR and ADR, respectively) as well as polyp size, morphology and histology characteristics. Results: 262 subjects (168 males, mean age 66.3±4.3 years) were colonoscoped (133 patients with HD-PHL while 129 with SD-OL). PDR and ADR were comparable within the two optical systems. The HD-PHL group resulted in a PDR 55.6% and ADR 43.6%; the SD-OL group had PDR 56.6% and ADR 45.7%. HD-PHL was significantly superior to SD-OL in detection of flat adenomas (18.6% vs 5.2%, p<0.001), but not detection of pedunculated or sessile polyps. Patient comfort, use of sedation and endoscopist perception of procedural difficulty resulted similar despite the use of Scope Guide with SD-OL. Conclusion: PDR and ADR were not significantly different between devices. The high-resolution colonoscopy system HD-PHL may improve polyp detection as compared with standard resolution technology in detecting flat adenomas. This advantage may have clinically significant implications for missed lesion rates and post-colonoscopy interval colorectal cancer rates