98 research outputs found
Psychometric validation of the Bangla fear of COVID-19 Scale: confirmatory factor analysis and Rasch analysis
The recently developed Fear of COVID-19 Scale (FCV-19S) is a seven-item uni-dimensional scale that assesses the severity of fears of COVID-19. Given the rapid increase of COVID-19 cases in Bangladesh, we aimed to translate and validate the FCV-19S in Bangla. The forward-backward translation method was used to translate the English version of the questionnaire into Bangla. The reliability and validity properties of the Bangla FCV-19S were rigorously psychometrically evaluated (utilizing both confirmatory factor analysis and Rasch analysis) in relation to socio-demographic variables, national lockdown variables, and response to the Bangla Health Patient Questionnaire. The sample comprised 8550 Bangladeshi participants. The Cronbach α value for the Bangla FCV-19S was 0.871 indicating very good internal reliability. The results of the confirmatory factor analysis showed that the uni-dimensional factor structure of the FCV-19S fitted well with the data. The FCV-19S was significantly correlated with the nine-item Bangla Patient Health Questionnaire (PHQ-90) (r = 0.406,
Translational Radiomics: Defining the Strategy Pipeline and Considerations for Application-Part 1: From Methodology to Clinical Implementation.
Enterprise imaging has channeled various technological innovations to the field of clinical radiology, ranging from advanced imaging equipment and postacquisition iterative reconstruction tools to image analysis and computer-aided detection tools. More recently, the advancements in the field of quantitative image analysis coupled with machine learning-based data analytics, classification, and integration have ushered us into the era of radiomics, which has tremendous potential in clinical decision support as well as drug discovery. There are important issues to consider to incorporate radiomics as a clinically applicable system and a commercially viable solution. In this two-part series, we offer insights into the development of the translational pipeline for radiomics from methodology to clinical implementation (Part 1) and from that to enterprise development (Part 2)
The influence of ethylene and ethylene modulators on shoot organogenesis in tomato
[EN] The influence of ethylene and ethylene modulators on the in vitro organogenesis of tomato was studied using a highly regenerating accession of the wild tomato Solanum pennellii and an F1 plant resulting from a cross between Solanum pennellii and Solanum lycopersicum cv. Anl27, which is known to have a low regeneration frequency. Four ethylene-modulating compounds, each at four levels, were used, namely: cobalt chloride (CoCl 2), which inhibits the production of ethylene; AgNO 3 (SN), which inhibits ethylene action; and Ethephon and the precursor 1-aminocyclopropane-1-carboxylic acid (ACC), which both promote ethylene synthesis. Leaf explants of each genotype were incubated on shoot induction medium supplemented with each of these compounds at 0, 10 or 15 days following bud induction. The results obtained in our assays indicate that ethylene has a significant influence on tomato organogenesis. Concentrations of ethylene lower than the optimum (according to genotype) at the beginning of the culture may decrease the percentage of explants with buds (B), produce a delay in their appearance, or indeed inhibit bud formation. This was observed in S. pennellii and the F1 explants cultured on media with SN (5.8-58.0 ¿M) as well as in the F1 explants cultured on medium with 21.0 ¿M CoCl 2. The percentage of explants with shoots (R) and the mean number of shoots per explant with shoots (PR) also diminished in media that contained SN. Shoots isolated from these explants were less developed compared to those isolated from control explants. On the other hand, ethylene supplementation may contribute to enhancing shoot development. The number of isolable shoots from S. pennellii explants doubled in media with ACC (9.8-98.0 ¿M). Shoots isolated from explants treated with ethylene releasing compounds showed a higher number of nodes when ACC and Ethephon were added at 10 days (in F1 explants) or at 15 days (in S. pennellii) after the beginning of culture. Thus, the importance of studying not only the concentration but also the timing of the application of regulators when developing regeneration protocols has been made manifest. An excess of ethylene supplementation may produce an inhibitory effect, as was observed when using Ethephon (17.2-69.0 ¿M). These results show the involvement of ethylene in tomato organogenesis and lead us to believe that ethylene supplementation may contribute to enhancing regeneration and shoot development in tomato. © 2012 Springer Science+Business Media B.V.Carlos Trujillo has a predoctoral fellowship from the Spanish 'Ministerio de Educacion y Ciencia'. This work has been funded by Universitat Politecnica de Valencia (PAID 05-10). The technical assistance of N. Palacios and the revision of the manuscript's English by J. Bergen are gratefully acknowledged.Trujillo Moya, C.; Gisbert Domenech, MC. (2012). The influence of ethylene and ethylene modulators on shoot organogenesis in tomato. Plant Cell, Tissue and Organ Culture. 111(1):141-148. https://doi.org/10.1007/s11240-012-0168-zS1411481111Abeles FB, Morgan PW, Saltveit ME (1992) Ethylene in plant biology. Academic Press, San DiegoBhatia P, Ashwath N, Senaratna T, David M (2004) Tissue culture studies of tomato (Lycopersicon esculentum). Plant Cell Tiss Org Cult 78:1–21Bhatia P, Ashwath N, Midmore DJ (2005) Effects of genotype, explant orientation, and wounding on shoot regeneration in tomato. In Vitro Cell Dev Biol-Plant 41:457–464Biddington NL (1992) The Influence of ethylene in plant-tissue culture. Plant Growth Regul 11:173–187Brown DC, Thorpe TA (1995) Crop improvement through tissue culture. World J Microbiol Biotechnol 11(4):409–415Chraibi KMB, Latche A, Roustan JP, Fallot J (1991) Stimulation of shoot regeneration from cotyledons of Helianthus annuus by the ethylene inhibitors,silver and cobalt. Plant Cell Rep 10:204–207Devi R, Dhaliwal MS, Kaur A, Gosal SS (2008) Effect of growth regulators on in vitro morphogenic response of tomato. Indian J Biotechnol 7:526–530Dias LLC, Santa-Catarina C, Ribeiro DM, Barros RS, Floh EIS, Otoni WC (2009) Ethylene and polyamine production patterns during in vitro shoot organogenesis of two passion fruit species as affected by polyamines and their inhibitor. Plant Cell Tiss Org Cult 99:199–208Dimasi-Theriou K, Economou AS (1995) Ethylene enhances shoot formation in cultures of the peach rootstock GF-677 (Prunus persica × P. amygdalus). Plant Cell Rep 15:87–90Gisbert C, Arrillaga I, Roig LA, Moreno V (1999) Adquisition of a collection of Lycopersicon pennellii (Corr. D’Arcy) transgenic plants with uidA and nptII marker genes. J Hortic Sci Biotechnol 74:105–109Hughes KW (1981) In vitro ecology: exogenous factors affecting growth and morphogenesis in plant culture systems. Environ Exp Bot 21:281–288Huxter TJ, Thorpe TA, Reid DM (1981) Shoot initiation in light- and darkgrown tobacco callus: the role of ethylene. Physiol Plant 53:319–326Kumar PP, Lakshmanan P, Thorpe TA (1998) Regulation of morphogenesis in plant tissue culture by ethylene. In Vitro Cell Dev Biol Plant 34:94–103Lima JE, Benedito VA, Figueira A, Peres LEP (2009) Callus, shoot and hairy root formation in vitro as affected by the sensitivity to auxin and ethylene in tomato mutants. Plant Cell Rep 28:1169–1177Lu J, Vahala J, Pappinen A (2011) Involvement of ethylene in somatic embryogenesis in Scots pine (Pinus sylvestris L.). Plant Cell Tiss Org Cult 107:25–33Mohiuddin AKM, Chowdhury MKU, Abdullah ZC, Napis S (1997) Influence of silver nitrate (ethylene inhibitor) on cucumber in vitro shoot regeneration. Plant Cell Tiss Org Cult 51:75–78Moshkov IE, Novikova GV, Hall MA, George EF (2008) Plant Growth Regulators III: ethylene. In: George EF, Hall MA, Klerk G-JD (eds) Plant Propaga-tion by Tissue Culture, vol 1. 3rd edn. Springer, The Netherlands, pp 239–248Murashige T, Skoog F (1962) A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol Plant 15:473–497Osman MG, Khalafalla MM (2010) Promotion of in vitro shoot formation from shoot tip of tomato (Lycopersicon esculentum Mill. cv. Omdurman) by ethylene inhibitors. Int J Curr Res 4:82–86Ptak A, El Tahchy A, Wyzgolik G, Henry M, Laurain-Mattar D (2010) Effects of ethylene on somatic embryogenesis and galantamine content in Leucojum aestivum L. cultures. Plant Cell Tiss Org Cult 102:61–67Pua EC, Sim GE, Chi GL, Kong LF (1996) Synergistic effects of ethylene inhibitors and putrescine on shoot regeneration from hypocotyl explants of Chinese radish (Raphanus sativus L. var. longipinnatus Bailey) in vitro. Plant Cell Rep 15:685–690Reid MS (1995) Ethylene in plant growth, development and senescence. In: Davies PJ (ed) Plant hormones: physiology, biochemistry and molecular biology, 2nd edn. Kluwer Acad Publ, The Netherlands, pp 486–508Trujillo-Moya C, Gisbert C, Vilanova S, Nuez F (2011) Localization of QTLs for in vitro plant regeneration in tomato. BMC Plant Biol 11: art.140Tsuchisaka A, Theologis A (2004) Heterodimeric interactions among the 1-amino-cyclopropane-1-carboxylate synthase polypeptides encoded by the Arabidopsis gene family. Proc Natl Acad Sci USA 101:2275–2280Vogel JP, Woeste KE, Theologis A, Kieber JJ (1998) Recessive and dominant mutations in the ethylene biosynthetic gene ACS5 of Arabidopsis confer cytokinin insensitivity and ethylene overproduction, respectively. Proc Natl Acad Sci USA 95:4766–477
Late gastrointestinal tissue effects after hypofractionated radiation therapy of the pancreas
Background
To consolidate literature reports of serious late gastrointestinal toxicities after hypofractionated radiation treatment of pancreatic cancer and attempt to derive normal tissue complication probability (NTCP) parameters using the Lyman-Kutcher-Burman model.
Methods
Published reports of late grade 3 or greater gastrointestinal toxicity after hypofractionated treatment of pancreatic cancer were reviewed. The biologically equivalent dose in 1.8 Gy fractions was calculated using the EQD model. NTCP parameters were calculated using the LKB model assuming 1–5 % of the normal tissue volume was exposed to the prescription dose with α/β ratios of 3 or 4.
Results
A total of 16 human studies were examined encompassing a total of 1160 patients. Toxicities consisted of ulcers, hemorrhages, obstructions, strictures, and perforations. Non-hemorrhagic and non-perforated ulcers occurred at a rate of 9.1 % and were the most commonly reported toxicity. Derived NTCP parameter ranges were as follows: n = 0.38–0.63, m = 0.48–0.49, and TD50 = 35–95 Gy. Regression analysis showed that among various study characteristics, dose was the only significant predictor of toxicity.
Conclusions
Published gastrointestinal toxicity reports after hypofractionated radiotherapy for pancreatic cancer were compiled. Median dose was predictive of late grade ≥ 3 gastrointestinal toxicity. Preliminary NTCP parameters were derived for multiple volume constraints
A Review of Time Courses and Predictors of Lipid Changes with Fenofibric Acid-Statin Combination
Fibrates activate peroxisome proliferator activated receptor α and exert beneficial effects on triglycerides, high-density lipoprotein cholesterol, and low density lipoprotein subspecies. Fenofibric acid (FA) has been studied in a large number of patients with mixed dyslipidemia, combined with a low- or moderate-dose statin. The combination of FA with simvastatin, atorvastatin and rosuvastatin resulted in greater improvement of the overall lipid profile compared with the corresponding statin dose. The long-term efficacy of FA combined with low- or moderate- dose statin has been demonstrated in a wide range of patients, including patients with type 2 diabetes mellitus, metabolic syndrome, or elderly subjects. The FA and statin combination seems to be a reasonable option to further reduce cardiovascular risk in high-risk populations, although trials examining cardiovascular disease events are missing
Cell cycle checkpoint status in human malignant mesothelioma cell lines: response to gamma radiation
Knowledge of the function of the cell cycle checkpoints in tumour cells may be important to develop treatment strategies for human cancers. The protein p53 is an important factor that regulates cell cycle progression and apoptosis in response to drugs. In human malignant mesothelioma, p53 is generally not mutated, but may be inactivated by SV40 early region T antigen (SV40 Tag). However, the function of p53 has not been investigated in mesothelioma cells. Here, we investigated the function of the cell cycle checkpoints in six human mesothelioma cell lines (HMCLs) by studying the cell distribution in the different phases of the cell cycle by flow cytometry, and expression of cell cycle proteins, p53, p21WAF1/CIP1 and p27KIP1. In addition, we studied p53 gene mutations and expression of SV40 Tag. After exposure to γ-radiation, HMCLs were arrested either in one or both phases of the cell cycle, demonstrating a heterogeneity in cell cycle control. G1 arrest was p21WAF1/CIP1- and p53-dependent. Lack of arrest in G1 was not related to p53 mutation or binding to SV40 Tag, except in one HMCL presenting a missense mutation at codon 248. These results may help us to understand mesothelioma and develop new treatments
First-Principles Study of the Electronic and Magnetic Properties of Defects in Carbon Nanostructures
Understanding the magnetic properties of graphenic nanostructures is
instrumental in future spintronics applications. These magnetic properties are
known to depend crucially on the presence of defects. Here we review our recent
theoretical studies using density functional calculations on two types of
defects in carbon nanostructures: Substitutional doping with transition metals,
and sp-type defects created by covalent functionalization with organic and
inorganic molecules. We focus on such defects because they can be used to
create and control magnetism in graphene-based materials. Our main results are
summarized as follows: i)Substitutional metal impurities are fully understood
using a model based on the hybridization between the states of the metal
atom and the defect levels associated with an unreconstructed D carbon
vacancy. We identify three different regimes, associated with the occupation of
distinct hybridization levels, which determine the magnetic properties obtained
with this type of doping; ii) A spin moment of 1.0 is always induced by
chemical functionalization when a molecule chemisorbs on a graphene layer via a
single C-C (or other weakly polar) covalent bond. The magnetic coupling between
adsorbates shows a key dependence on the sublattice adsorption site. This
effect is similar to that of H adsorption, however, with universal character;
iii) The spin moment of substitutional metal impurities can be controlled using
strain. In particular, we show that although Ni substitutionals are
non-magnetic in flat and unstrained graphene, the magnetism of these defects
can be activated by applying either uniaxial strain or curvature to the
graphene layer. All these results provide key information about formation and
control of defect-induced magnetism in graphene and related materials.Comment: 40 pages, 17 Figures, 62 References; Chapter 2 in Topological
Modelling of Nanostructures and Extended Systems (2013) - Springer, edited by
A. R. Ashrafi, F. Cataldo, A. Iranmanesh, and O. Or
Neoadjuvant capecitabine, radiotherapy, and bevacizumab (CRAB) in locally advanced rectal cancer: results of an open-label phase II study
<p>Abstract</p> <p>Background</p> <p>Preoperative capecitabine-based chemoradiation is a standard treatment for locally advanced rectal cancer (LARC). Here, we explored the safety and efficacy of the addition of bevacizumab to capecitabine and concurrent radiotherapy for LARC.</p> <p>Methods</p> <p>Patients with MRI-confirmed stage II/III rectal cancer received bevacizumab 5 mg/kg i.v. 2 weeks prior to neoadjuvant chemoradiotherapy followed by bevacizumab 5 mg/kg on Days 1, 15 and 29, capecitabine 825 mg/m<sup>2 </sup>twice daily on Days 1-38, and concurrent radiotherapy 50.4 Gy (1.8 Gy/day, 5 days/week for 5 weeks + three 1.8 Gy/day), starting on Day 1. Total mesorectal excision was scheduled 6-8 weeks after completion of chemoradiotherapy. Tumour regression grades (TRG) were evaluated on surgical specimens according to Dworak. The primary endpoint was pathological complete response (pCR).</p> <p>Results</p> <p>61 patients were enrolled (median age 60 years [range 31-80], 64% male). Twelve patients (19.7%) had T3N0 tumours, 1 patient T2N1, 19 patients (31.1%) T3N1, 2 patients (3.3%) T2N2, 22 patients (36.1%) T3N2 and 5 patients (8.2%) T4N2. Median tumour distance from the anal verge was 6 cm (range 0-11). Grade 3 adverse events included dermatitis (n = 6, 9.8%), proteinuria (n = 4, 6.5%) and leucocytopenia (n = 3, 4.9%). Radical resection was achieved in 57 patients (95%), and 42 patients (70%) underwent sphincter-preserving surgery. TRG 4 (pCR) was recorded in 8 patients (13.3%) and TRG 3 in 9 patients (15.0%). T-, N- and overall downstaging rates were 45.2%, 73.8%, and 73.8%, respectively.</p> <p>Conclusions</p> <p>This study demonstrates the feasibility of preoperative chemoradiotherapy with bevacizumab and capecitabine. The observed adverse events of neoadjuvant treatment are comparable with those previously reported, but the pCR rate was lower.</p
Financing micro-entrepreneurs for poverty alleviation: a performance analysis of microfinance services offered by BRAC, ASA, and Proshika from Bangladesh
Microfinance services have emerged as an effective tool for financing microentrepreneurs to alleviate poverty. Since the 1970s, development theorists have considered non-governmental microfinance institutions (MFIs) as the leading practitioners of sustainable development through financing micro-entrepreneurial activities. This study evaluates the impact of micro-finance services provided by MFIs on poverty alleviation. In this vein, we examine whether microfinance services contribute to poverty alleviation, and also identify bottlenecks in micro-finance programs and operations. The results indicate that the micro-loans have a statistically significant positive impact on the poverty alleviation index and consequently improve the living standard of borrowers by increasing their level of income
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