The Effect of Partial Root Drying on Antioxidant Activity in Different Agricultural Crops

Partial root drying (PRD) is a new irrigation strategy which applies alternating regimes of irrigation to half the root system while the other half dries out. Many published results showed that PRD may save water without significant effect on yield. The aim of this work was to compare the effects of PRD with full irrigation (FI) on yield and antioxidant activity in grape berry, potato tuber and tomato fruit. in both experimental conditions (field and polytunnel), the soil water content in FI treatment was kept close to field capacity, although in PRD treatment, 70o/o of the irrigation water in FI was uppti"a to one half of the root system, and irrigation was shifted according to soil water content decrease in the dry side of the root zone. At the end of the vegetation season, analyses of total yield of fruit and tubers and their quality were carried out. Antioxidant activity of tomato fruit ethanolic extract was evaluated against 2,2'-azinobis (3-eyhylbenzothiazoline-6-sulfonic acid) radical cation (ABTS'*) and expressed as Trolox (6-hydroxy-2,5,7,8-tetramethylchtoman-2- carboxylic acid) equivalent antioxidant capacity (TEAC)' In general, treatment differences in yield were not significant for either crop although WUE and anti,oxidant activity in the PRD treatments were higher than in the FI treatment for investigated crops. These results for all PRD-treated crops showed that PRD could be a useful strategy to save irrigation water without significantly sacrificing either the quantity or quality of yield

A pilot study of transrectal endoscopic ultrasound elastography in inflammatory bowel disease

BACKGROUND: Using standard diagnostic algorithms it is not always possible to establish the correct phenotype of inflammatory bowel disease which is essential for therapeutical decisions. Endoscopic ultrasound elastography is a new endoscopic procedure which can differentiate the stiffness of normal and pathological tissue by ultrasound. Therefore, we aimed to investigate the role of transrectal ultrasound elastography in distiction between Crohn's disease and ulcerative colitis. ----- METHODS: A total 30 Crohn's disease, 25 ulcerative colitis, and 28 non-inflammatory bowel disease controls were included. Transrectal ultrasound elastography was performed in all patients and controls. In all ulcerative coltis patients and 80% of Crohn's disease patients endoscopy was performed to assess disease activity in the rectum. ----- RESULTS: Significant difference in rectal wall thickness and strain ratio was detected between patients with Crohn's disease and controls (p = 0.0001). CD patients with active disease had higher strain ratio than patients in remission (p = 0.02). In ulcerative colitis group a significant difference in rectal wall thickness was found between controls and patients with active disease (p = 0.03). A significant difference in rectal wall thickness (p = 0.02) and strain ratio (p = 0.0001) was detected between Crohn's disease and ulcerative colitis patient group. Crohn's disease patients with active disease had a significantly higher strain ratio compared to ulcerative colitis patients with active disease (p = 0.0001). ----- CONCLUSION: Transrectal ultrasound elastography seems to be a promising new diagnostic tool in the field of inflammatory bowel disease. Further study on a larger cohort of patients is needed to definitely assess the role of transrectal ultrasound elastography in inflammatory bowel disease

Feasibility of joystick guided colonoscopy

The flexible endoscope is increasingly used to perform minimal invasive interventions. A novel add-on platform allows single-person control of both endoscope and instrument at the site of intervention. The setup changes the current routine of handling the endoscope. This study aims to determine if the platform allows effective and efficient manipulation to position the endoscope at potential intervention sites throughout the bowel. Five experts in flexible endoscopy first performed three colonoscopies on a computer simulator using the conventional angulation wheels. Next they trained with the joystick interface to achieve their personal level of intubation time with low pain score. 14 PhD students (novices) without hands-on experience performed the same colonoscopy case using either the conventional angulation wheels or joystick interface. Both novice groups trained to gain the average expert level. The cecal intubation time, pain score and visualization performance (% of bowel wall) were recorded. All experts reached their personal intubation time in 6 ± 6 sessions. Three experts completed their learning curve with low pain score in 8 ± 6 sessions. The novices required 11 ± 6 sessions using conventional angulation wheels, and 12 ± 6 sessions using the joystick interface. There was no difference in the visualization performance between the novice and between the expert groups. This study shows that the add-on platform enables endoscope manipulation required to perform colonoscopy. Experts need only a relatively short training period. Novices are as effective and as efficient in endoscope manipulation when comparing the add-on platform with conventional endoscope contro

A hydraulically driven colonoscope

BACKGROUND: Conventional colonoscopy requires a high degree of operator skill and is often painful for the patient. We present a preliminary feasibility study of an alternative approach where a self-propelled colonoscope is hydraulically driven through the colon. METHODS: A hydraulic colonoscope which could be controlled manually or automatically was developed and assessed in a test bed modelled on the anatomy of the human colon. A conventional colonoscope was used by an experienced colonoscopist in the same test bed for comparison. Pressures and forces on the colon were measured during the test. RESULTS: The hydraulic colonoscope was able to successfully advance through the test bed in a comparable time to the conventional colonoscope. The hydraulic colonoscope reduces measured loads on artificial mesenteries, but increases intraluminal pressure compared to the colonoscope. Both manual and automatically controlled modes were able to successfully advance the hydraulic colonoscope through the colon. However, the automatic controller mode required lower pressures than manual control, but took longer to reach the caecum. CONCLUSIONS: The hydraulic colonoscope appears to be a viable device for further development as forces and pressures observed during use are comparable to those used in current clinical practice

Guiding principles for the development and application of solid-phase phosphorus adsorbents for freshwater ecosystems

While a diverse array of phosphorus (P)-adsorbent materials is currently available for application to freshwater aquatic systems, selection of the most appropriate P-adsorbents remains problematic. In particular, there has to be a close correspondence between attributes of the P-adsorbent, its field performance, and the management goals for treatment. These management goals may vary from a rapid reduction in dissolved P to address seasonal enrichments from internal loading, targeting external fluxes due to anthropogenic sources, or long term inactivation of internal P inventories contained within bottom sediments. It also remains a challenge to develop new methods and materials that are ecologically benign and cost-effective. We draw on evidence in the literature and the authors’ personal experiences in the field, to summarise the attributes of a range of P-adsorbent materials. We offer 'guiding principles' to support practical use of existing materials and outline key development needs for new materials

Acid unfolding of beta-2-microglobulin by repulsion of + charges

Peer reviewe

Hydrophobic core and surface charges of human beta-2-microglobulin probed by CD measurements

The roles of hydrophobic bonding and charge electrostatics in the stabilization of human beta-2-microglobulin have been probed by variations in solution conditions and monitored by circular dichroism in the near and far UV regions. Sodium perchlorate initially gives a decrease in intensity of the positive 234 nm peak in the near UV followed by a shift of this peak to negative ellipticity at high perchlorate concentration. These 234 nm changes indicate a new environment for a tyrosyl chromophore(s). A conformational rearrangement of the beta-sheet sandwich must occur since all six tyrosines of human beta-2-microglubulin are located in the two beta-sheets of this sandwich. A slight decrease in intensity for the 200 nm positive peak in the far UV indicates a less close packing of the beta-sheets at high perchlorate. In other experiments, enthalpy and entropy values have been calculated from thermal unfolding studies at 50 and 180 mm NaCl for pH values 6.0 and 8.0. Larger enthalpy values are obtained at higher NaCl concentration consistent with salt shielding of predominantly unfavorable charge interactions. These enthalpy differences are relatively large suggesting that charge electrostatics are energetically significant in stabilization of human beta-2-microglobulin.Peer reviewe

Discriminatory ability of calcaneal quantitative ultrasound in the assessment of bone status in patients with inflammatory bowel disease

A high incidence of bone disease in patients with inflammatory bowel disease (IBD) requires frequent monitoring of skeletal status and, for that reason, evaluation of radiation-free technology is an issue of interest. Our objective was to appraise the parameters of calcaneal quantitative ultrasound (QUS): broadband ultrasound attenuation (BUA), speed of sound (SOS) and stiffness index (QUI), and establish their t-score values to investigate discriminatory ability of QUS in IBD patients with metabolic bone disease. The study included 126 patients (Crohn's disease [n = 94] and ulcerative colitis [n = 32]), and 228 age- and sex-matched healthy volunteers. Bone status was evaluated on the same day by calcaneal QUS and dual-energy x-ray absorptiometry (DXA) at spine (L1-L4) and total hip. All QUS measurements were lower in patients compared with healthy controls (BUA p < 0.001; SOS p < 0.001; QUI p < 0.001) and correlated significantly but inversely with disease duration (r = -0.3, p = 0.002). There was no difference with respect to type of disease (Crohn's disease or ulcerative colitis) or corticosteroid therapy. All three QUS t-scores were significantly lower in patients who had previously sustained fragile fractures (n = 28) than in those without fracture in their history (n = 98) (t-scores: BUA -2.0 vs. -1.3, p = 0.008; SOS -2.1 vs. -1.4, p = 0.02: QUI -2.3 vs. -1.5, p = 0.009). Axial DXA was not significantly different between the fracture and nonfracture patients (-1.7 vs. -1.2, p = 0.1), whereas total hip DXA showed a discriminatory power between the two (-1.6 vs. -0.7, p = 0.001). Patients with t-score < -1.0 scanned by DXA were classified as bone disease. The sensitivity of QUS to identify bone disease was 93% and specificity 63%. The sensitivity of QUS to detect osteopenia was 84% and 72% for osteoporosis. Alternatively, lower negative QUS t-score cutoff </= -1.8 identified 83% of osteoporosis at lumbar spine and 100% at total hip. All three QUS variables had t-scores less than -1.8 when osteoporosis was detected at both spine and hip. However, the subgroup of IBD patients with QUI t-score cutoff </= -1.8 still included 26% of individuals with normal bone status. Calcaneal QUS measurements may identify patients with IBD who are at a higher risk of fracture independently of DXA measurements. However, QUS showed poor agreement with bone status scanned by DXA and a low discriminatory power between osteopenia and osteoporosis