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1.
J Hosp Infect ; 143: 25-32, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37852539

RESUMO

BACKGROUND: vanB-carrying vancomycin-resistant Enterococcus faecium (VREfm) of the sequence types 80 (ST80) and ST117 have dominated Germany in the past. In 2020, our hospital witnessed a sharp increase in the proportion of vanA-positive VREfm. AIM: To attempt to understand these dynamics through whole-genome sequencing (WGS) and analysis of nosocomial transmissions. METHODS: At our hospital, the first VREfm isolate per patient, treated during 2020, was analysed retrospectively using specific vanA/vanB PCR, WGS, multi-locus sequence typing (MLST), and core-genome (cg) MLST. Epidemiologic links between VRE-positive patients were assessed using hospital occupancy data. FINDINGS: Isolates from 319 out of 356 VREfm patients were available for WGS, of which 181 (56.7%) fulfilled the ECDC definition for nosocomial transmission. The high load of nosocomial cases is reflected in the overall high clonality rate with only three dominating sequence (ST) and complex types (CT), respectively: the new emerging strain ST1299 (100% vanA, 77.4% CT1903), and the well-known ST80 (90.0% vanB, 81.0% CT1065) and ST117 (78.0% vanB, 65.0% CT71). The ST1299 isolates overall, and the subtype CT1903 in particular, showed high isolate clonality, which demonstrates impressively high spreading potential. Overall, 152 out of 319 isolates had an allelic cgMLST difference of ≤3 to another, including 91 (59.6%) ST1299. Occupancy data identified shared rooms (3.7%), shared departments (6.2%), and VRE-colonized prior room occupants (0.6%) within 30 days before diagnosis as solid epidemiological links. CONCLUSION: A new emerging VREfm clone, ST1299/CT1903/vanA, dominated our institution in 2020 and has been an important driver of the increasing VREfm rates.


Assuntos
Infecção Hospitalar , Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Enterococos Resistentes à Vancomicina , Humanos , Vancomicina , Tipagem de Sequências Multilocus , Enterococcus faecium/genética , Estudos Retrospectivos , Universidades , Enterococos Resistentes à Vancomicina/genética , Infecção Hospitalar/epidemiologia , Infecções por Bactérias Gram-Positivas/epidemiologia , Proteínas de Bactérias/genética
2.
Vaccine ; 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37833124

RESUMO

CatSper is a voltage dependent calcium ion channel present in the principal piece of sperm tail. It plays a crucial role in sperm hyperactivated motility and so in fertilization. Extracellular loops of mouse sperm CatSper were used to develop a vaccine to achieve protection from pregnancy. These loops were inserted at one of the three hypervariable regions of Human Papilloma Virus (HPV) capsid protein (L1). Recombinant vaccines were expressed in E.coli as inclusion body (IB), purified, refolded and assembled into virus-like particles (VLP) in vitro, and adsorbed on alum. Four vaccine candidates were tested in Balb/C mice. All the constructs proved immunogenic, one showed contraceptive efficacy. This recombinant contraceptive vaccine is a non-hormonal intervention and is expected to give long-acting protection from undesired pregnancies.

3.
J Hosp Infect ; 141: 119-128, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37734679

RESUMO

Vancomycin-resistant enterococci (VRE) cause many infections in the healthcare context. Knowledge regarding the epidemiology and burden of VRE infections, however, remains fragmented. We aimed to summarize recent studies on VRE epidemiology and outcomes in hospitals, long-term-care facilities (LTCFs) and nursing homes worldwide based on current epidemiological reports. We searched MEDLINE/PubMed, the Cochrane Library, and Web of Science for observational studies, which reported on VRE faecium and faecalis infections in in-patients published between January 2014 and December 2020. Outcomes were incidence, infection rate, mortality, length of stay (LOS), and healthcare costs. We conducted a meta-analysis on mortality (PROSPERO registration number: CRD42020146389). Of 681 identified publications, 57 studies were included in the analysis. Overall quality of evidence was moderate to low. VRE incidence was rarely and heterogeneously reported. VRE infection rate differed highly (1-55%). The meta-analysis showed a higher mortality for VRE faecium bloodstream infections (BSIs) compared with VSE faecium BSIs (risk ratio, RR 1.46; 95% confidence interval (CI) 1.17-1.82). No difference was observed when comparing VRE faecium vs VRE faecalis BSI (RR 1.00, 95% CI 0.52-1.93). LOS was higher in BSIs caused by E. faecium vs E. faecalis. Only three studies reported healthcare costs. In contrast to previous findings, our meta-analysis of included studies indicates that vancomycin resistance independent of VRE species may be associated with a higher mortality. We identified a lack of standardization in reporting outcomes, information regarding healthcare costs, and state-of-the-art microbiological species identification methodology, which may inform the set-up and reporting of future studies.


Assuntos
Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Sepse , Enterococos Resistentes à Vancomicina , Humanos , Vancomicina , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Enterococcus faecalis , Infecções por Bactérias Gram-Positivas/microbiologia , Sepse/tratamento farmacológico
4.
Stat Pap (Berl) ; 64(4): 1275-1304, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37650050

RESUMO

The paper covers the design and analysis of experiments to discriminate between two Gaussian process models with different covariance kernels, such as those widely used in computer experiments, kriging, sensor location and machine learning. Two frameworks are considered. First, we study sequential constructions, where successive design (observation) points are selected, either as additional points to an existing design or from the beginning of observation. The selection relies on the maximisation of the difference between the symmetric Kullback Leibler divergences for the two models, which depends on the observations, or on the mean squared error of both models, which does not. Then, we consider static criteria, such as the familiar log-likelihood ratios and the Fréchet distance between the covariance functions of the two models. Other distance-based criteria, simpler to compute than previous ones, are also introduced, for which, considering the framework of approximate design, a necessary condition for the optimality of a design measure is provided. The paper includes a study of the mathematical links between different criteria and numerical illustrations are provided.

5.
Methods Mol Biol ; 2647: 197-210, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37041336

RESUMO

Somatic cell nuclear transfer (SCNT) has been successfully applied to clone animals of several species. Pigs are one of the main livestock species for food production and are also important for biomedical research due to their physiopathological similarities with humans. In the past 20 years, clones of several swine breeds have been produced for a variety of purposes, including biomedical and agricultural applications. In this chapter, we describe a protocol to produce cloned pigs by SCNT.


Assuntos
Clonagem de Organismos , Técnicas de Transferência Nuclear , Suínos , Animais , Humanos , Clonagem de Organismos/métodos
6.
Minerva Cardiol Angiol ; 71(4): 463-472, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36912167

RESUMO

BACKGROUND: The association between QRS narrowing and response to cardiac resynchronization therapy (CRT) has been investigated by several studies, but their findings remain inconclusive. Aim of our study was to explore the relationship between QRS Index and echocardiographic response to CRT. METHODS: This multicenter, retrospective analysis included 326 consecutive patients (mean age was 70.0±10.1 years old; males 76.7%) who underwent CRT-D implantation in primary and secondary prevention between 2018 and 2020. The estimation of QRS shortening after CRT-D implantation was precisely assessed through the QRS Index, calculated as follows: [(QRS duration before implantation - paced QRS duration)/QRS duration before implantation]*100. RESULTS: After a mean follow-up of 12.7±4.5 months, 55.2% (180/326) of the patients showed an echocardiographic response to CRT. The median [25-75th] QRS Index was 3.85% [-14.1% - +13.9%]. The best predictive cut-off value of QRS Index was 1.40% (sensitivity 70.4%, specificity 64.5%, AUC 0.70). In patients with left bundle branch block, the median [25-75th] QRS Index was 9.85% [+3.87% - +16.7%]. In this subgroup, the AUC was 0.737 and the best predictive cut-off of QRS Index was 2.20% (sensitivity 78.3%, specificity 67%). The multivariable model showed that only left ventricular ejection fraction and QRS Index were independently associated with CRT response (respectively OR 0.92, CI 95% 0.86-0.98, P=0.01 and OR 1.057, CI 95% 1.026-1.089, P<0.001). CONCLUSIONS: The QRS Index tightly correlated with CRT response. Only LVEF and QRS Index were independently associated with echocardiographic response to CRT.


Assuntos
Terapia de Ressincronização Cardíaca , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Volume Sistólico/fisiologia , Função Ventricular Esquerda , Eletrocardiografia , Estudos Retrospectivos , Resultado do Tratamento , Ecocardiografia
7.
Stat Biosci ; 15(1): 31-56, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36923259

RESUMO

The statistical analysis of enzyme kinetic reactions usually involves models of the response functions which are well defined on the basis of Michaelis-Menten type equations. The error structure, however, is often without good reason assumed as additive Gaussian noise. This simple assumption may lead to undesired properties of the analysis, particularly when simulations are involved and consequently negative simulated reaction rates may occur. In this study, we investigate the effect of assuming multiplicative log normal errors instead. While there is typically little impact on the estimates, the experimental designs and their efficiencies are decisively affected, particularly when it comes to model discrimination problems.

8.
Biom J ; 65(4): e2100386, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36642810

RESUMO

Model-based geostatistical design involves the selection of locations to collect data to minimize an expected loss function over a set of all possible locations. The loss function is specified to reflect the aim of data collection, which, for geostatistical studies, could be to minimize the prediction uncertainty at unobserved locations. In this paper, we propose a new approach to design such studies via a loss function derived through considering the entropy about the model predictions and the parameters of the model. The approach includes a multivariate extension to generalized linear spatial models, and thus can be used to design experiments with more than one response. Unfortunately, evaluating our proposed loss function is computationally expensive so we provide an approximation such that our approach can be adopted to design realistically sized geostatistical studies. This is demonstrated through a simulated study and through designing an air quality monitoring program in Queensland, Australia. The results show that our designs remain highly efficient in achieving each experimental objective individually, providing an ideal compromise between the two objectives. Accordingly, we advocate that our approach could be adopted more generally in model-based geostatistical design.


Assuntos
Poluição do Ar , Incerteza , Teorema de Bayes , Poluição do Ar/efeitos adversos , Modelos Lineares
9.
Foods ; 11(12)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35741939

RESUMO

Improving production efficiency while enhancing pork quality is pivotal for strengthening sustainable pork production. Being able to study both gene expression and indices of pork quality from the same anatomical location of an individual animal would better enable research conducted to study relationships between animal growth and carcass merit. To facilitate gene expression studies, adipose and muscle tissue samples are often collected immediately following exsanguination to maximize RNA integrity, which is a primary determinant of the sensitivity of RNA-based assays, such as real-time PCR. However, collecting soft tissue samples requires cutting through the hide or skin. This leaves the underlying tissue exposed during scalding, poses possible food safety issues, and potentially confounds pork quality measures. To overcome these limitations, the effect of tissue sample timing post-harvest on RNA integrity, real-time PCR results, and pork quality measurements was investigated by sampling subcutaneous adipose tissue and longissimus thoracis et lumborum muscle immediately following either exsanguination, scalding, or chilling. Sampling time did not affect RNA quality, as determined by the RNA integrity number of RNA samples purified from either adipose (RIN; p > 0.54) or muscle tissue (p > 0.43). Likewise, the sampling time did not influence the results of real-time PCR analysis of gene expression when comparing RNA samples prepared from adipose or muscle tissue immediately following either exsanguination or scalding (p > 0.92). However, sampling tissue prior to scalding resulted in a greater visual color score (p < 0.001) and lesser L* (p < 0.001) and b* (p < 0.001) values without impacting the 24 h pH (p < 0.41). These results suggested that if both RNA-based assays and meat quality endpoints are to be performed at the same anatomical location on an animal, tissue sampling to facilitate RNA-based assays should occur at a time point immediately following scalding. These findings demonstrated that sampling of adipose and muscle tissue can be delayed until after scalding/dehairing without decreasing the RNA integrity or altering the results of real-time PCR assays, while doing so was associated with little impact on measures of pork quality.

10.
Suicide Life Threat Behav ; 52(4): 705-715, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35307857

RESUMO

OBJECTIVE: Loneliness is a well-established risk factor for suicide in young adults, but the mechanisms involved are still unclear. Drawing on the Interpersonal Theory of Suicide, the Evolutionary Model of Loneliness, and Prospect Theory, we examined if high and low levels of loneliness are associated with different patterns of response to losses or gains of belongingness. METHODS: A sample of 188 students completed the UCLA-Loneliness scale (version 3) and measures of suicide risk. Participants in the top and bottom tertiles of loneliness scores completed a computerized task designed to induce changes (gains, losses) or consistency in risk factors for suicide (belongingness, burdensomeness) over time, and examined the effect on desire to quit the task. RESULTS: The results showed that the high loneliness group exhibited a larger magnitude of effect on desire to quit from gaining belongingness than for losing belongingness. In contrast, the low loneliness group showed a larger change in desire to quit from losing belongingness than gaining belongingness. CONCLUSION: The findings provide preliminary experimental support for distinct profiles of suicide risk based on prevailing levels of loneliness. The findings are discussed in relation to a need for increased precision in theoretical models of suicide and loneliness.


Assuntos
Solidão , Suicídio , Humanos , Relações Interpessoais , Teoria Psicológica , Fatores de Risco , Estudantes , Ideação Suicida , Adulto Jovem
11.
Life (Basel) ; 12(2)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35207459

RESUMO

CRISPR/Cas9 technology is a powerful tool used for genome manipulation in different cell types and species. However, as with all new technologies, it still requires improvements. Different factors can affect CRISPR/Cas efficiency in zygotes, which influence the total cost and complexity for creating large-animal models for research. This study evaluated the importance of zygote cell cycle stage between early-injection (within 6 h post activation/fertilization) versus late-injection (14-16 h post activation/fertilization) when the CRISPR/Cas9 components were injected and the inhibition of the homologous recombination (HR) pathway of DNA repair on gene editing, embryo survival and development on embryos produced by fertilization, sperm injection, somatic cell nuclear transfer, and parthenogenetic activation technologies. Injections at the late cell cycle stage decreased embryo survival (measured as the proportion of unlysed embryos) and blastocyst formation (68.2%; 19.3%) compared to early-stage injection (86.3%; 28.8%). However, gene editing was higher in blastocysts from late-(73.8%) vs. early-(63.8%) injected zygotes. Inhibition of the HR repair pathway increased gene editing efficiency by 15.6% in blastocysts from early-injected zygotes without compromising embryo development. Our finding shows that injection at the early cell cycle stage along with HR inhibition improves both zygote viability and gene editing rate in pig blastocysts.

12.
Adv Exp Med Biol ; 1354: 335-343, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34807450

RESUMO

Much of biomedical oriented research is conducted with animal models. Over the years, rodents (primarily rats and mice) have emerged as the preferred species for basic biochemistry, cell biology, physiology and nutrition studies. In the past, dogs have been used for the evaluation of dietary protein quality and other aspects of animal nitrogen metabolism and physiology, cardiovascular and endocrine research. At an increasing rate, pigs have also been used as a model species in biomedical research. Pigs are readily available in various mature sizes and genotypic/phenotypic traits, and there are many anatomic, nutritional and physiologic similarities between human beings and pigs. Many notable reviews summarizing the role of pigs in biomedical studies have already been published and these are cited below. The present review focuses on characteristics that make pigs an excellent biomedical animal model in particular in obesity, diabetes and cardiovascular research. To procure an animal model for obesity, irrespective of species used, these animals must be fed a dense caloric diet (high fat) to achieve an experimental working model within a reasonable period. This review also focuses on a putative role of gastrointestinal microbiota in obesity as obese animals exhibit a shift in the distribution of gastrointestinal microbial phyla from lean animals. But to date such results have not pinpointed a treatable cause for obesity. Sometimes, the choice of sampling sites for microbial assessment in many reports can be questioned as the microbial content and phyla distribution in easily collected fecal samples may differ from those obtained directly from the small intestine and upper colon. While pigs are still utilized in many countries for medical surgery practice, this has been discontinued in US medical schools.


Assuntos
Pesquisa Biomédica , Microbioma Gastrointestinal , Sus scrofa , Animais , Dieta , Fezes , Camundongos , Ratos , Suínos
13.
Anim Reprod Sci ; 233: 106851, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34560342

RESUMO

There is growing evidence that greater than homeostatic blood concentrations of nonesterified fatty acids (NEFAs) and ß-hydroxybutyrate (BHBA) have negative consequences on dairy cow's fertility, but effects on cell homeostasis in the reproductive system is not completely understood. In this study, lipids accumulation, reactive oxygen species (ROS) concentrations, abundance of gene transcripts, and immunofluorescence signal of H3K4me3 and H3K9me3 were evaluated in endometrial epithelial cells of cattle cultured with NEFAs (Oleic (OA), Stearic (SA) and Palmitic (PA) acids), BHBA, NEFAs + BHBA or each of the three NEFAs alone. The cellular lipids were in greater concentrations as a result of NEFAs + BHBA, NEFAs, SA or OA supplementation, but not by BHBA or PA. The ROS concentrations were greater when there were treatments with NEFAs + BHBA, NEFAs or BHBA. The relative mRNA abundance for genes involved in the regulation of apoptosis (XIAP), glucose transport (GLUT3), and DNA methylation (DNMT1) were greater when there were NEFAs + BHBA, but not NEFAs, BHBA, OA, SA or PA treatments. The immunofluorescence signal for H3K9me3 was greater when there were NEFAs + BHBA, NEFAs or PA, but not by BHBA, OA or SA treatments. These findings indicate that NEFAs and BHBA have an additive effect on endometrial cells of cattle by altering epigenetic markers and the expression of genes controlling important cellular pathways. Furthermore, there was cellular lipid accumulation and increased H3K9me3 in cultured bovine endometrial cells that was mainly induced by OA and PA treatments, respectively.


Assuntos
Endométrio/metabolismo , Ácidos Graxos não Esterificados/administração & dosagem , Histonas/metabolismo , Ácido 3-Hidroxibutírico/administração & dosagem , Ácido 3-Hidroxibutírico/sangue , Animais , Bovinos , Endométrio/citologia , Células Epiteliais/metabolismo , Ácidos Graxos não Esterificados/sangue , Feminino , Imunofluorescência , Ácido Oleico/administração & dosagem , Ácido Palmítico/administração & dosagem , Espécies Reativas de Oxigênio/metabolismo , Ácidos Esteáricos/administração & dosagem
14.
Diagnostics (Basel) ; 11(7)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34359382

RESUMO

Far too often, one meets patients who went for years or even decades from doctor to doctor without obtaining a valid diagnosis. This brings pain to millions of patients and their families, not to speak of the enormous costs. Often patients cannot tell precisely enough which factors (or combinations thereof) trigger their problems. If conventional methods fail, we propose the use of statistics and algebra to provide doctors much more useful inputs from patients. We use statistical regression for triggering factors of medical problems, and in particular, "balanced incomplete block designs" for factors detection. These methods can supply doctors with much more valuable inputs and can also find combinations of multiple factors through very few tests. In order to show that these methods do work, we briefly describe a case in which these methods helped to solve a 60-year-old problem in a patient and provide some more examples where these methods might be particularly useful. As a conclusion, while regression is used in clinical medicine, it seems to be widely unknown in diagnosing. Statistics and algebra can save the health systems much money, as well as the patients a lot of pain.

15.
HNO ; 69(6): 517-528, 2021 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-33942126

RESUMO

Postoperative care is a crucial aspect for the success of paranasal sinus interventions. Basic procedures include saline nasal wash, which should be started on the first postoperative day, topical steroids, and antibiotics in cases of infection. Medical treatment involves aspiration of secretion in the inferior meatus during the first week. Removal of scabs in the surgical field should be carried out under endoscopic control beginning at the second week. Intervals are scheduled individually. Occlusion of the nose for the time of epithelium regeneration provides a moist space in the ethmoid, which improves wound healing.


Assuntos
Seios Paranasais , Endoscopia , Humanos , Seios Paranasais/cirurgia , Cuidados Pós-Operatórios , Cicatrização
16.
Biol Reprod ; 105(1): 76-86, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-33889948

RESUMO

Conditions of impaired energy and nutrient homeostasis, such as diabetes and obesity, are associated with infertility. Hyperglycemia increases endoplasmic reticulum stress as well as oxidative stress and reduces embryo development and quality. Oxidative stress also causes deoxyribonucleic acid damage, which impairs embryo quality and development. The natural bile acid tauroursodeoxycholic acid reduces endoplasmic reticulum stress and rescues developmentally incompetent late-cleaving embryos, as well as embryos subjected to nuclear stress, suggesting the endoplasmic reticulum stress response, or unfolded protein response, and the genome damage response are linked. Tauroursodeoxycholic acid acts via the Takeda-G-protein-receptor-5 to alleviate nuclear stress in embryos. To evaluate the role of tauroursodeoxycholic acid/Takeda-G-protein-receptor-5 signaling in embryo unfolded protein response, we used a model of glucose-induced endoplasmic reticulum stress. Embryo development was impaired by direct injection of tauroursodeoxycholic acid into parthenogenetically activated oocytes, whereas it was improved when tauroursodeoxycholic acid was added to the culture medium. Attenuation of the Takeda-G-protein-receptor-5 precluded the positive effect of tauroursodeoxycholic acid supplementation on development of parthenogenetically activated and fertilized embryos cultured under standard conditions and parthenogenetically activated embryos cultured with excess glucose. Moreover, attenuation of tauroursodeoxycholic acid/Takeda-G-protein-receptor-5 signaling induced endoplasmic reticulum stress, oxidative stress and cell survival genes, but decreased expression of pluripotency genes in parthenogenetically activated embryos cultured under excess glucose conditions. These data suggest that Takeda-G-protein-receptor-5 signaling pathways link the unfolded protein response and genome damage response. Furthermore, this study identifies Takeda-G-protein-receptor-5 signaling as a potential target for mitigating fertility issues caused by nutrient excess-associated blastomere stress and embryo death.


Assuntos
Colagogos e Coleréticos/farmacologia , Estresse do Retículo Endoplasmático/fisiologia , Estresse Oxidativo/fisiologia , Receptores Acoplados a Proteínas G/genética , Sus scrofa/embriologia , Ácido Tauroquenodesoxicólico/farmacologia , Animais , Blastômeros/fisiologia , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/fisiologia , Glucose/efeitos adversos , Receptores Acoplados a Proteínas G/metabolismo , Resposta a Proteínas não Dobradas/fisiologia
17.
Adv Exp Med Biol ; 1285: 29-42, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33770401

RESUMO

Proteins have been recognized for a long time as an important dietary nutritional component for all animals. Most amino acids were isolated and characterized in the late nineteenth and early twentieth century. Initially dietary proteins were ranked high to low quality by growth and N balance studies. By the 1950s interest had shifted to studying the roles of individual amino acids in amino acid requirements by feeding studies with non-ruminants as rodents, poultry and pigs. The direct protein feeding approaches followed by measurements of nutritional outcomes were not possible however in ruminants (cattle and sheep). The development of measuring free amino acids by ion exchange chromatography enabled plasma amino acid analysis. It was thought that plasma amino acid profiles were useful in nutritional studies on proteins and amino acids. With non-ruminants, nutritional interpretations of plasma amino acid studies were possible. Unfortunately with beef cattle, protein/amino acid nutritional adequacy or requirements could not be routinely determined with plasma amino acid studies. In dairy cows, however, much valuable understanding was gained from amino acid studies. Concurrently, others studied amino acid transport in ruminant small intestines, the role of peptides in ruminant N metabolism, amino acid catabolism (in the animal) with emphasis on branched-chain amino acid catabolism. In addition, workable methodologies for studying protein turnover in ruminants were developed. By the 1990s, nutritionists could still not determine amino acid requirements with empirical experimental studies in beef cattle. Instead, computer software (expert systems) based on the accumulated knowledge in animal and ruminal amino acids, energy metabolism and protein production were realized and revised frequently. With these tools, the amino acid requirements, daily energy needs, ruminal and total gastrointestinal tract digestion and performance of growing beef cattle could be predicted.


Assuntos
Aminoácidos , Ração Animal , Ração Animal/análise , Animais , Bovinos , Dieta , Proteínas Alimentares , Digestão , Feminino , Ovinos , Suínos
19.
JMIR Med Inform ; 8(12): e21982, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33284125

RESUMO

BACKGROUND: Respondent engagement of questionnaires in health care is fundamental to ensure adequate response rates for the evaluation of services and quality of care. Conventional survey designs are often perceived as dull and unengaging, resulting in negative respondent behavior. It is necessary to make completing a questionnaire attractive and motivating. OBJECTIVE: The aim of this study is to compare the user experience of a chatbot questionnaire, which mimics intelligent conversation, with a regular computer questionnaire. METHODS: The research took place at the preoperative outpatient clinic. Patients completed both the standard computer questionnaire and the new chatbot questionnaire. Afterward, patients gave their feedback on both questionnaires by the User Experience Questionnaire, which consists of 26 terms to score. RESULTS: The mean age of the 40 included patients (25 [63%] women) was 49 (SD 18-79) years; 46.73% (486/1040) of all terms were scored positive for the chatbot. Patients preferred the computer for 7.98% (83/1040) of the terms and for 47.88% (498/1040) of the terms there were no differences. Completion (mean time) of the computer questionnaire took 9.00 minutes by men (SD 2.72) and 7.72 minutes by women (SD 2.60; P=.148). For the chatbot, completion by men took 8.33 minutes (SD 2.99) and by women 7.36 minutes (SD 2.61; P=.287). CONCLUSIONS: Patients preferred the chatbot questionnaire over the computer questionnaire. Time to completion of both questionnaires did not differ, though the chatbot questionnaire on a tablet felt more rapid compared to the computer questionnaire. This is an important finding because it could lead to higher response rates and to qualitatively better responses in future questionnaires.

20.
Biom J ; 62(4): 1090-1104, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31957085

RESUMO

Experimental design applications for discriminating between models have been hampered by the assumption to know beforehand which model is the true one, which is counter to the very aim of the experiment. Previous approaches to alleviate this requirement were either symmetrizations of asymmetric techniques, or Bayesian, minimax, and sequential approaches. Here we present a genuinely symmetric criterion based on a linearized distance between mean-value surfaces and the newly introduced tool of flexible nominal sets. We demonstrate the computational efficiency of the approach using the proposed criterion and provide a Monte-Carlo evaluation of its discrimination performance on the basis of the likelihood ratio. An application for a pair of competing models in enzyme kinetics is given.


Assuntos
Biometria/métodos , Modelos Estatísticos , Teorema de Bayes , Funções Verossimilhança , Método de Monte Carlo
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