Hydrogels have been used as scaffolds for biomineralization in tissue engineering and regenerative medicine for the repair and treatment of many tissue types. In the present work, we studied an amino ...acid-based material that is attached to protecting groups and self-assembles into biocompatible and stable nanostructures that are suitable for tissue engineering applications. Specifically, the doubly protected aspartic residue (Asp) with fluorenyl methoxycarbonyl (Fmoc) protecting groups have been shown to lead to the formation of well-ordered fibrous structures. Many amino acids and small peptides which are modified with protecting groups display relatively fast self-assembly and exhibit remarkable physicochemical properties leading to three-dimensional (3D) networks, the trapping of solvent molecules, and forming hydrogels. In this study, the self-assembling fibrous structures are targeted toward calcium binding and act as nucleation points for the binding of the available phosphate groups. The cell viability, proliferation, and osteogenic differentiation of pre-osteoblastic cells cultured on the formed hydrogel under various conditions demonstrate that hydrogel formation in CaCl
and CaCl
-Na
HPO
solutions lead to calcium ion binding onto the hydrogels and enrichment with phosphate groups, respectively, rendering these mechanically stable hydrogels osteoinductive scaffolds for bone tissue engineering.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The Oxford WebQ is an online 24-hour dietary questionnaire that is appropriate for repeated administration in large-scale prospective studies, including the UK Biobank study and the Million Women ...Study. We compared the performance of the Oxford WebQ and a traditional interviewer-administered multiple-pass 24-hour dietary recall against biomarkers for protein, potassium, and total sugar intake and total energy expenditure estimated by accelerometry. We recruited 160 participants in London, United Kingdom, between 2014 and 2016 and measured their biomarker levels at 3 nonconsecutive time points. The measurement error model simultaneously compared all 3 methods. Attenuation factors for protein, potassium, total sugar, and total energy intakes estimated as the mean of 2 applications of the Oxford WebQ were 0.37, 0.42, 0.45, and 0.31, respectively, with performance improving incrementally for the mean of more measures. Correlation between the mean value from 2 Oxford WebQs and estimated true intakes, reflecting attenuation when intake is categorized or ranked, was 0.47, 0.39, 0.40, and 0.38, respectively, also improving with repeated administration. These correlations were similar to those of the more administratively burdensome interviewer-based recall. Using objective biomarkers as the standard, the Oxford WebQ performs well across key nutrients in comparison with more administratively burdensome interviewer-based 24-hour recalls. Attenuation improves when the average value is taken over repeated administrations, reducing measurement error bias in assessment of diet-disease associations.
myfood24 Is an online 24-h dietary assessment tool developed for use among British adolescents and adults. Limited information is available regarding the validity of using new technology in assessing ...nutritional intake among adolescents. Thus, a relative validation of myfood24 against a face-to-face interviewer-administered 24-h multiple-pass recall (MPR) was conducted among seventy-five British adolescents aged 11–18 years. Participants were asked to complete myfood24 and an interviewer-administered MPR on the same day for 2 non-consecutive days at school. Total energy intake (EI) and nutrients recorded by the two methods were compared using intraclass correlation coefficients (ICC), Bland–Altman plots (using between and within-individual information) and weighted κ to assess the agreement. Energy, macronutrients and other reported nutrients from myfood24 demonstrated strong agreement with the interview MPR data, and ICC ranged from 0·46 for Na to 0·88 for EI. There was no significant bias between the two methods for EI, macronutrients and most reported nutrients. The mean difference between myfood24 and the interviewer-administered MPR for EI was −230 kJ (−55 kcal) (95 % CI −490, 30 kJ (−117, 7 kcal); P=0·4) with limits of agreement ranging between 39 % (3336 kJ (−797 kcal)) lower and 34 % (2874 kJ (687 kcal)) higher than the interviewer-administered MPR. There was good agreement in terms of classifying adolescents into tertiles of EI (κ
w
=0·64). The agreement between day 1 and day 2 was as good for myfood24 as for the interviewer-administered MPR, reflecting the reliability of myfood24. myfood24 Has the potential to collect dietary data of comparable quality with that of an interviewer-administered MPR.
Introduction : Overweight and obesity affects over 70% of the UK population and is a major risk factor for the development of co-morbidities, including type 2 diabetes and cardiovascular disease. ...There now exists a considerable evidence base for the management of obesity. However, this is not the case for the prevention of obesity. Preventing weight gain in periods of life where there is an elevated risk of fat mass expansion could be beneficial to preventing associated diseases in later life. This protocol investigates the impact of novel food ingredient inulin propionate ester (IPE) in the prevention of weight gain. This trial aims to investigate the primary hypothesis that IPE has a superior effect on preventing body weight gain, compared with inulin, in young (<40 years old) adults over 12 months, whilst also investigating several complementary mechanisms that may explain the prevention of weight gain and improved long-term energy balance from consuming IPE. Methods : In this multi-centre, double-blind, randomised, parallel-group study, eligible participants will be randomly assigned to consume 10g IPE or 10g inulin (control) daily for 12 months. Study visits will be conducted at baseline, two-month, six-month and 12-month time points. The primary outcome is weight gain from baseline to 12 months. Secondary outcomes will examine changes in metabolic and cardiovascular health biomarkers, body composition and appetite. A mechanistic sub-group will explore causal mechanisms around energy balance, body composition, appetite regulation and the gut microbiota. Based on the power calculation, the sample size required is 270 participants or 135 per study group. Ethics and dissemination : The trial protocol and participant-facing documents have been reviewed and approved, by the London Hampstead Ethics Committee (REC Reference 19/LO/0095, 29 th January 2019). Upon completion, the trial results will be published in peer-reviewed journals and presented at scientific conferences. Trial registration number: ISRCTN16299902, 1 st March 2018.
Introduction: Overweight and obesity affects over 70% of the UK population and is a major risk factor for the development of co-morbidities, including type 2 diabetes and cardiovascular disease. ...There now exists a considerable evidence base for the management of obesity. However, this is not the case for the prevention of obesity. Preventing weight gain in periods of life where there is an elevated risk of fat mass expansion could be beneficial to preventing associated diseases in later life. This protocol investigates the impact of novel food ingredient inulin propionate ester (IPE) in the prevention of weight gain. This trial aims to investigate the primary hypothesis that IPE has a superior effect on preventing body weight gain, compared with inulin, in young (<40 years old) adults over 12 months, whilst also investigating several complementary mechanisms that may explain the prevention of weight gain and improved long-term energy balance from consuming IPE.
Methods: In this multi-centre, double-blind, randomised, parallel-group study, eligible participants will be randomly assigned to consume 10g IPE or 10g inulin (control) daily for 12 months. Study visits will be conducted at baseline, two-month, six-month and 12-month time points. The primary outcome is weight gain from baseline to 12 months. Secondary outcomes will examine changes in metabolic and cardiovascular health biomarkers, body composition and appetite. A mechanistic sub-group will explore causal mechanisms around energy balance, body composition, appetite regulation and the gut microbiota. Based on the power calculation, the sample size required is 270 participants or 135 per study group.
Ethics and dissemination: The trial protocol and participant-facing documents have been reviewed and approved, by the London Hampstead Ethics Committee (REC Reference 19/LO/0095, 29
th January 2019). Upon completion, the trial results will be published in peer-reviewed journals and presented at scientific conferences.
Trial registration number: ISRCTN16299902, 1
st March 2018.
In adult
Ceratitis capitata males, the fat body synthesizes and secretes into the haemolymph two major male specific serum polypeptides (MSSP-α and β). Furthermore, the male fat body contains two ...abundant mRNAs which yield, in a cell-free system, two pre-MSSPs which undergo post-translational modifications to give rise to the mature MSSPs.
In vivo and
in vitro studies during development suggested that the onset of MSSPs' synthesis is regulated at the level of transcription while at latter stages of development the synthesis of the MSSPs is regulated at the translational level. The synthesis of the two MSSPs is not co-ordinated during development. This non-coordinated synthesis does not seem to be due to differential transcription levels of the respective genes but rather to different translational rates.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We investigated the linear viscoelasticity of bottlebrush polystyrenes (PSs) with total molar masses ranging from 132 to 769 kg/mol, bearing short side chains (with molar masses of 5 and 7 kg/mol, ...well below the entanglement limit of PS). Their estimated length to diameter ratio was smaller than 1, corresponding to a globular conformation and conforming to the molar mass dependence of the radii and to recent computer simulation results. The master curves were constructed by means of time–temperature superposition and featured a hierarchical relaxation (glassy, side-chain, intermediate, and terminal regimes) along with the absence of a rubbery plateau, indicating that the entire macromolecules behaved as unentangled polymers, though with some distinct features. The analysis of the dependence of storage and loss moduli on oscillatory frequency revealed cooperative side-chain dynamics at intermediate frequencies because of their mutual repulsion and Rouse-like dynamics at low frequencies. The zero-shear viscosity scaled with the total molar mass of the bottlebrush as η0 ≈ M w,bottlebrush like Rouse chains; however, the respective dependence of the terminal flow time appeared to be stronger. The estimated values of the fragility index suggested that these unentangled bottlebrushes became stiffer with increasing length of the side chains but remained less stiff compared to linear PSs of the same total mass. These results are compared with and contrasted against bottlebrush data from the literature, suggesting universalities and distinct features likely attributed to chemical differences and calling for further investigations.
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IJS, KILJ, NUK, PNG, UL, UM
The worldwide increase in the occurrence and dissemination of KPC β-lactamases among gram-negative pathogens makes critical the early detection of these enzymes. Boronic acid disk tests using ...different antibiotic substrates were evaluated for detection of KPC-possessing Klebsiella pneumoniae isolates. A total of 57 genotypically confirmed KPC-possessing K. pneumoniae isolates with varying carbapenem MICs were examined. To measure the specificity of the tests, 106 non-KPC-possessing isolates (89 K. pneumoniae and 17 Escherichia coli isolates) were randomly selected among those exhibiting reduced susceptibility to cefoxitin, expanded-spectrum cephalosporins, or carbapenems. As many as 56, 53, and 40 of the non-KPC-possessing isolates harbored extended-spectrum β-lactamases, metallo-β-lactamases, and plasmid-mediated AmpC β-lactamases, respectively. By use of CLSI methodology and disks containing imipenem, meropenem, or cefepime, either alone or in combination with 400 μg of boronic acid, all 57 KPC producers gave positive results (sensitivity, 100%) whereas all 106 non-KPC producers were negative (specificity, 100%). The meropenem duplicate disk with or without boronic acid demonstrated the largest differences in inhibition zone diameters between KPC producers and non-KPC producers. By use of disks containing ertapenem, all isolates were correctly differentiated except for five AmpC producers that gave false-positive results (sensitivity, 100%; specificity, 95.3%). These practical and simple boronic acid disk tests promise to be very helpful for the accurate differentiation of KPC-possessing K. pneumoniae isolates, even in regions where different broad-spectrum β-lactamases are widespread.
Background The increasing frequency of class A KPC enzymes and class B metallo-β-lactamases (MBLs) among Enterobacteriaceae as well as their possible co-production makes their early differentiation ...urgent. Methods A simple phenotypic algorithm employing three combined-disc tests consisting of meropenem alone and with phenylboronic acid (PBA), EDTA, or both PBA and EDTA was designed for the differentiation of KPC and MBL enzymes. Augmentation of the zone of inhibition by ≥5 mm was considered a positive combined-disc test result. A total of 141 genotypically confirmed carbapenemase-positive Enterobacteriaceae clinical isolates (63 KPC producers, 47 MBL producers, and 31 KPC and MBL producers) with various carbapenem MICs were examined. For comparison, 84 genotypically confirmed carbapenemase-negative Enterobacteriaceae clinical isolates 39 extended-spectrum β-lactamase (ESBL) producers, 22 AmpC producers, and 23 ESBL and AmpC producers were also tested. Results The phenotypic algorithm was able to differentiate MBL from KPC producers as well as to detect the possible co-production of both carbapenemases (positive result only with the combined-disc test using meropenem alone and with both PBA and EDTA). The method detected all KPC or MBL producers (sensitivity 100%) as well as 30 of the KPC and MBL producers (sensitivity 96.8%). All three combined-disc tests were negative for non-carbapenemase-producing isolates, except two ESBL and AmpC producers that gave positive combined-disc tests using meropenem alone and with PBA and both PBA and EDTA (specificity for KPC detection 98.8%). Conclusions This phenotypic method is very helpful to detect carbapenemase production and provides a simple algorithm for the differentiation of KPC and MBL enzymes, especially in regions where KPC- and MBL-possessing Enterobacteriaceae are highly prevalent.
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