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1.
Medicina (Kaunas) ; 60(1)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38256359

RESUMEN

Background and Objectives: Total knee arthroplasty (TKA) has become the treatment of choice for advanced osteoarthritis. The aim of this paper was to show the possibilities of optimizing the Perth CT protocol, which is highly effective for preoperative planning and postoperative assessment of alignment. Materials and Methods: The cross-sectional study comprised 16 patients for preoperative planning or postoperative evaluation of TKA. All patients were examined with the standard and optimized Perth CT protocol using advance techniques, including automatic exposure control (AEC), iterative image reconstruction (IR), as well as a single-energy projection-based metal artifact reduction algorithm for eliminating prosthesis artifacts. The effective radiation dose (E) was determined based on the dose report. Imaging quality is determined according to subjective and objective (values of signal to noise ratio (SdNR) and figure of merit (FOM)) criteria. Results: The effective radiation dose with the optimized protocol was significantly lower compared to the standard protocol (p < 0.001), while in patients with the knee prosthesis, E increased significantly less with the optimized protocol compared to the standard protocol. No significant difference was observed in the subjective evaluation of image quality between protocols (p > 0.05). Analyzing the objective criteria for image quality optimized protocols resulted in lower SdNR values and higher FOM values. No significant difference of image quality was determined using the SdNR and FOM as per the specified protocols and parts of extremities, and for the presence of prothesis. Conclusions: Retrospecting the ALARA ('As Low As Reasonably Achievable') principles, it is possible to optimize the Perth CT protocol by reducing the kV and mAs values and by changing the collimation and increasing the pitch factor. Advanced IR techniques were used in both protocols, and AEC was used in the optimized protocol. The effective dose of radiation can be reduced five times, and the image quality will be satisfactory.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Humanos , Estudios Transversales , Algoritmos , Extremidades , Fatiga
2.
Medicina (Kaunas) ; 59(8)2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37629792

RESUMEN

Background and Objectives: The aim of this study was to assess the differences in Doppler indices of the uterine (Ut), umbilical (UA), and middle cerebral artery (MCA) in diabetic versus non-diabetic pregnancies by conducting a comprehensive systematic review of the literature with a meta-analysis. Materials and Methods: PubMed, Web of Science, and SCOPUS were searched for studies that measured the pulsatility index (PI), resistance index (RI), and systolic/diastolic ratio index (S/D ratio) of the umbilical artery, middle cerebral artery, and uterine artery in diabetic versus non-diabetic pregnancies. Two reviewers independently evaluated the eligibility of studies, abstracted data, and performed quality assessments according to standardized protocols. The standardized mean difference (SMD) was used as a measure of effect size. Heterogeneity was assessed using the I2 statistic. Publication bias was evaluated by means of funnel plots. Results: A total of 62 publications were included in the qualitative and 43 in quantitative analysis. The UA-RI, UtA-PI, and UtA-S/D ratios were increased in diabetic compared with non-diabetic pregnancies. Subgroup analysis showed that levels of UtA-PI were significantly higher during the third, but not during the first trimester of pregnancy in diabetic versus non-diabetic pregnancies. No differences were found for the UA-PI, UA-S/D ratio, MCA-PI, MCA-RI, MCA-S/D ratio, or UtA-RI between diabetic and non-diabetic pregnancies. Conclusions: This meta-analysis revealed the presence of hemodynamic changes in uterine and umbilical arteries, but not in the middle cerebral artery in pregnancies complicated by diabetes.


Asunto(s)
Diabetes Mellitus , Arteria Cerebral Media , Femenino , Embarazo , Humanos , Arteria Cerebral Media/diagnóstico por imagen , Feto , Atención Prenatal , Pelvis
3.
Genes (Basel) ; 14(6)2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37372375

RESUMEN

A high level of genetic purity in crop varieties must be achieved and maintained for agronomic performance, encouraging investment and innovation in plant breeding and ensuring that the improvements in productivity and quality imparted by breeders are delivered to the consumer. Since the success of hybrid seed production is dependent upon the genetic purity of the parental lines, in this study, the experimental F1exp maize hybrid and its parental inbreeds were used as a model system to examine the discriminative power of morphological, biochemical and SSR markers for seed purity assay. The highest number of off-type plants was estimated by morphological markers. According to the comparison of prolamins and albumins banding patterns of parental and derived F1exp seeds, genetic impurities could not be detected. Molecular analysis detected two types of genetic profile irregularity. Beside its use for verifying varieties of maize, report on umc1545 primer pair ability to detect non-specific bands (i.e., off-types), in both the maternal component and F1exp, which is the first report on this issue yet, strongly supports the recommendation of this SSR marker use for more accurate and time-efficient maize hybrids and parental lines genetic pyrity testing.


Asunto(s)
Fitomejoramiento , Zea mays , Zea mays/genética , Semillas/genética , Pruebas Genéticas
4.
Artículo en Inglés | MEDLINE | ID: mdl-34574500

RESUMEN

BACKGROUND: The objective of this study was to assess the complex relationship between the multiple determinants of the caregiving process, the caregiver burden, and depression during the COVID-19 pandemic in Serbia. METHODS: A cross-sectional study was conducted on a nationally representative sample (n = 798) during the COVID-19 pandemic in Serbia from March to September 2020. A nine-section questionnaire designed for this study included the characteristics of caregivers, characteristics of care and care recipients, COVID-19 related questions, and the following standardized instruments: 12-Item Short-Form Health Survey, Fatigue Severity Scale, Activities of Daily Living Scale and Instrumental Activities of Daily Living Scale, Zarit Caregiver Burden Scale, and Beck Depression Inventory. Path analysis was used for the simultaneous assessment of the direct and indirect relationships of all determinants. RESULTS: More than two thirds (71.9%) of informal caregivers experienced a burden, and more than one quarter (27.1%) had depression symptomatology. Self-rated physical health, need for psychosocial support, and caregiver burden were the main direct predictors of depression. Multiple determinants of the caregiving process had indirect effects on depressive symptomatology via the caregiver burden as a mediating factor. CONCLUSIONS: The subjective burden presented a significant risk factor for depressive symptoms in caregivers during the COVID-19 pandemic. The provision of psychosocial support was identified as an important opportunity to reduce depressive risk in informal caregivers.


Asunto(s)
COVID-19 , Depresión , Actividades Cotidianas , Cuidadores , Costo de Enfermedad , Estudios Transversales , Depresión/epidemiología , Humanos , Pandemias , SARS-CoV-2
5.
Food Technol Biotechnol ; 53(2): 171-179, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27904346

RESUMEN

Chokeberries (Aronia melanocarpa) are rarely used in diet in Croatia but they have high content of polyphenolic compounds and one of the highest in vitro antioxidant activities among fruits. The aim of this study is to compare the quality, phenolic content and antioxidant capacity of different chokeberry products (juices, powders, fruit tea, capsules and dried berries). It can be expected that processing influences antioxidant activity and phenolic content of final products reaching consumers. Characterisation of phenolic compounds was carried out by using spectroscopic methods (Folin-Ciocalteu and pH differential methods). Antioxidant activity of chokeberry products was determined using 2,2-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods. The results show that the investigated products contain high amount of phenols (3002 to 6639 mg per L and 1494 to 5292 mg per 100 g of dry matter) and lower amount of total anthocyanins (150 to 1228 mg per L and 141 to 2468 mg per 100 g of dry matter). The examined juices and other chokeberry products possess high antioxidant capacity (12.09 to 40.19 mmol per L or 58.49 to 191.31 mmol per 100 g of dry matter, respectively) and reducing power (38.71 to 79.86 mmol per L or 13.50 to 68.60 mmol per 100 g of dry matter, respectively). On the basis of phenolic content and antioxidant activity, capsules and powders stand out among other products. The study indicates that there are significant differences (p<0.05) in the quality, phenolic content and antioxidant capacity among examined products.

6.
Protoplasma ; 252(1): 335-43, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25081230

RESUMEN

Comparative biochemical characterization of class III peroxidase activity tightly bound to the cell walls of maize roots was performed. Ionically bound proteins were solubilized from isolated walls by salt washing, and the remaining covalently bound peroxidases were released, either by enzymatic digestion or by a novel alkaline extraction procedure that released covalently bound alkali-resistant peroxidase enzyme. Solubilized fractions, as well as the salt-washed cell wall fragments containing covalently bound proteins, were analyzed for peroxidase activity. Peroxidative and oxidative activities indicated that peroxidase enzymes were predominately associated with walls by ionic interactions, and this fraction differs from the covalently bound one according to molecular weight, isozyme patterns, and biochemical parameters. The effect of covalent binding was evaluated by comparison of the catalytic properties of the enzyme bound to the salt-washed cell wall fragments with the corresponding solubilized and released enzyme. Higher thermal stability, improved resistance to KCN, increased susceptibility to H2O2, stimulated capacity of wall-bound enzyme to oxidize indole-3-acetic acid (IAA) as well as the difference in kinetic parameters between free and bound enzymes point to conformational changes due to covalent binding. Differences in biochemical properties of ionically and covalently bound peroxidases, as well as the modulation of the enzyme properties as a result of covalent binding to the walls, indicate that these two fractions of apoplastic peroxidases play different roles.


Asunto(s)
Peroxidasas/metabolismo , Células Vegetales/metabolismo , Raíces de Plantas/metabolismo , Zea mays/enzimología , Isoenzimas/metabolismo , Oxidación-Reducción , Unión Proteica
7.
Food Chem ; 140(1-2): 390-7, 2013 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-23578658

RESUMEN

This report is aimed at intra-laboratory and inter-laboratory comparison of the results obtained during spectrophotometric and HPLC analyses of lycopene, ß-carotene and total carotenoids in tomato products and yellow maize flours/grits. Extensive statistical analyses are performed in order to identify the main sources of uncertainties which may occur when using: (i) different techniques/methods/approaches in the same/different laboratories, in various food samples, and (ii) to indicate the facts/conditions under which the biases between results may remain unidentified after applying statistical testing. Our data points to the inertness of t-test to detect significance of differences, particularly at low R values: in general, the higher correlation coefficient, the higher is sensitivity of statistical testing, especially of the paired t-test. Therefore, simple deviation of relationship line slope from unity could be used as additional evaluation parameter. This adds to reliable and objective quality assurance of foods in regard to carotenoids.


Asunto(s)
Carotenoides/análisis , Cromatografía Líquida de Alta Presión/métodos , Harina/análisis , Solanum lycopersicum/química , Espectrofotometría/métodos , Zea mays/química
8.
J Food Sci ; 77(2): S99-106, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22250766

RESUMEN

UNLABELLED: Quality index method scheme was developed for raw bogue (Boops boops) and evaluated it in a shelf-life study, using samples from wild fish aggregations at fish farms (BF) and from area not influenced by the fish farms (BW). Different environment influenced the shelf life of bogues; thus the maximum ice storage, evaluated from cooked samples, was found to be 17 d for BF and 12 d for BW. The calculated quality indexes (QIs) evolved linearly with storage time on ice (QI(BF) = 0.968x + 0.583, R(2) = 0.947, Std. Err. Est. = 1.41; QI(BW) = 1.212x + 0.474, R(2) = 0.972, Std. Err. Est. = 0.95). The multivariable analysis was used to identify the most effective variables during spoilage evolution. The sum of all demerit points showed higher correlation (R > 0.99) then any single parameters itself, indicating that the individual parameters could not replace the usage of 20 demerit points QIM scoring scheme in sensory assessment. The impact of farming cages was observed in fat (BF > 19%; BW < 2%) and water content (BF = 55%; BW = 77%) of bogues, but also in pH, dielectric properties, thiobarbituric acid index, and volatile amine changes. High correlations of these parameters with storage time and sensory assessment were observed. PRACTICAL APPLICATIONS: The catch landings of bogue make this species very important in the Mediterranean fishery production. The effect of finfish farms makes individual fish samples of this species different in size and chemical content, thus changing the rate and in which their postmortem changes occur. The practical use of the article is a new developed and species adopted descriptive scheme for bogue, ready to use for scientific and industrial freshness assessment providing the information on fish quality and its remaining shelf life in ice, taking into account the environmental conditions such as catching ground.


Asunto(s)
Manipulación de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Perciformes , Alimentos Marinos/normas , Animales , Acuicultura/métodos , Hielo/análisis , Metilaminas/análisis
9.
Plant Sci ; 181(4): 465-70, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21889053

RESUMEN

Isolated cell walls from maize (Zea mays L.) roots exhibited ionically and covalently bound NAD-specific malate dehydrogenase activity. The enzyme catalyses a rapid reduction of oxaloacetate and much slower oxidation of malate. The kinetic and regulatory properties of the cell wall enzyme solubilized with 1M NaCl were different from those published for soluble, mitochondrial or plasma membrane malate dehydrogenase with respect to their ATP, Pi, and pH dependence. Isoelectric focusing of ionically-bound proteins and specific staining for malate dehydrogenase revealed characteristic isoforms present in cell wall isolate, different from those present in plasma membranes and crude homogenate. Much greater activity of cell wall-associated malate dehydrogenase was detected in the intensively growing lateral roots compared to primary root with decreased growth rates. Presence of Zn(2+) and Cu(2+) in the assay medium inhibited the activity of the wall-associated malate dehydrogenase. Exposure of maize plants to excess concentrations of Zn(2+) and Cu(2+) in the hydroponic solution inhibited lateral root growth, decreased malate dehydrogenase activity and changed isoform profiles. The results presented show that cell wall malate dehydrogenase is truly a wall-bound enzyme, and not an artefact of cytoplasmic contamination, involved in the developmental processes, and detoxification of heavy metals.


Asunto(s)
Pared Celular/enzimología , Malato Deshidrogenasa/metabolismo , Raíces de Plantas/citología , Raíces de Plantas/enzimología , Zea mays/citología , Zea mays/enzimología , Pared Celular/efectos de los fármacos , Cobre/farmacología , Concentración de Iones de Hidrógeno/efectos de los fármacos , Focalización Isoeléctrica , Isoenzimas/aislamiento & purificación , Isoenzimas/metabolismo , Cinética , Malato Deshidrogenasa/aislamiento & purificación , Malatos/metabolismo , Oxaloacetatos/metabolismo , Oxidación-Reducción/efectos de los fármacos , Raíces de Plantas/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Solubilidad/efectos de los fármacos , Fracciones Subcelulares/efectos de los fármacos , Fracciones Subcelulares/enzimología , Zea mays/efectos de los fármacos , Zea mays/crecimiento & desarrollo , Zinc/farmacología
10.
Talanta ; 85(1): 569-74, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21645743

RESUMEN

In this paper a commercial electronic tongue (αAstree, Alpha M.O.S.) was applied for botanical classification and physicochemical characterization of honey samples. The electronic tongue was comprised of seven potentiometric sensors coupled with an Ag/AgCl reference electrode. Botanical classification was performed by PCA, CCA and ANN modeling on 12 samples of acacia, chestnut and honeydew honey. The physicochemical characterization of honey was obtained by ANN modeling and the parameters included were electrical conductivity, acidity, water content, invert sugar and total sugar. The initial reference values for the physicochemical parameters observed were determined by traditional methods. Botanical classification of honey samples obtained by ANN was 100% accurate while the highest correlation between observed and predicted values was obtained for electrical conductivity (0.999), followed by acidity (0.997), water content (0.994), invert sugar content (0.988) and total sugar content (0.979). All developed ANN models for rapid honey characterization and botanical classification performed excellently showing the potential of the electronic tongue as a tool in rapid honey analysis and characterization. The advantage of using such a technique is a simple sample preparation procedure, there are no chemicals involved and there are no additional costs except the initial measurements required for ANN model development.


Asunto(s)
Flores/química , Miel/análisis , Potenciometría/métodos , Ácidos/análisis , Carbohidratos/análisis , Conductividad Eléctrica , Electrodos , Análisis de los Alimentos/métodos , Miel/clasificación , Modelos Teóricos , Potenciometría/instrumentación , Agua/análisis
11.
Food Biophys ; 5(1): 24-33, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20401182

RESUMEN

The trans-lycopene content of fresh tomato homogenates was assessed by means of the laser photoacoustic spectroscopy, the laser optothermal window, micro-Raman spectroscopy, and colorimetry; none of these methods require the extraction from the product matrix prior to the analysis. The wet chemistry method (high-performance liquid chromatography) was used as the absolute quantitative method. Analytical figures of merit for all methods were compared statistically; best linear correlation was achieved for the chromaticity index a* and chroma C*.

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