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2.
Sci Rep ; 13(1): 19587, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37949906

RESUMO

Medical datasets inherently contain errors from subjective or inaccurate test results, or from confounding biological complexities. It is difficult for medical experts to detect these elusive errors manually, due to lack of contextual information, limiting data privacy regulations, and the sheer scale of data to be reviewed. Current methods for training robust artificial intelligence (AI) models on data containing mislabeled examples generally fall into one of several categories-attempting to improve the robustness of the model architecture, the regularization techniques used, the loss function used during training, or selecting a subset of data that contains cleaner labels. This last category requires the ability to efficiently detect errors either prior to or during training, either relabeling them or removing them completely. More recent progress in error detection has focused on using multi-network learning to minimize deleterious effects of errors on training, however, using many neural networks to reach a consensus on which data should be removed can be computationally intensive and inefficient. In this work, a deep-learning based algorithm was used in conjunction with a label-clustering approach to automate error detection. For dataset with synthetic label flips added, these errors were identified with an accuracy of up to 85%, while requiring up to 93% less computing resources to complete compared to a previous model consensus approach developed previously. The resulting trained AI models exhibited greater training stability and up to a 45% improvement in accuracy, from 69 to over 99% compared to the consensus approach, at least 10% improvement on using noise-robust loss functions in a binary classification problem, and a 51% improvement for multi-class classification. These results indicate that practical, automated a priori detection of errors in medical data is possible, without human oversight.


Assuntos
Inteligência Artificial , Aprendizado Profundo , Humanos , Algoritmos , Análise por Conglomerados , Consenso
3.
Appl Radiat Isot ; 190: 110509, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36306679

RESUMO

To determine the safety of using argon as a deuteron beam stopping material, the  40Ar(d,p)41Ar cross section was measured at average deuteron energies of 3.6 MeV, 5.5 MeV, and 7.0 MeV using an activation method. A 16-MeV deuteron beam produced by Lawrence Berkeley National Laboratory's 88-Inch Cyclotron was degraded to each energy by nickel foils and the front wall of an aluminum gas chamber. The reduced-energy deuterons were used to activate a sample of natAr gas. After each irradiation, the gas chamber's  41Ar activation was measured with a high-purity germanium detector. The cross sections measured were larger than a previous measurement by ∼40%.


Assuntos
Ciclotrons
4.
Hum Reprod ; 37(8): 1746-1759, 2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35674312

RESUMO

STUDY QUESTION: Can an artificial intelligence (AI) model predict human embryo ploidy status using static images captured by optical light microscopy? SUMMARY ANSWER: Results demonstrated predictive accuracy for embryo euploidy and showed a significant correlation between AI score and euploidy rate, based on assessment of images of blastocysts at Day 5 after IVF. WHAT IS KNOWN ALREADY: Euploid embryos displaying the normal human chromosomal complement of 46 chromosomes are preferentially selected for transfer over aneuploid embryos (abnormal complement), as they are associated with improved clinical outcomes. Currently, evaluation of embryo genetic status is most commonly performed by preimplantation genetic testing for aneuploidy (PGT-A), which involves embryo biopsy and genetic testing. The potential for embryo damage during biopsy, and the non-uniform nature of aneuploid cells in mosaic embryos, has prompted investigation of additional, non-invasive, whole embryo methods for evaluation of embryo genetic status. STUDY DESIGN, SIZE, DURATION: A total of 15 192 blastocyst-stage embryo images with associated clinical outcomes were provided by 10 different IVF clinics in the USA, India, Spain and Malaysia. The majority of data were retrospective, with two additional prospectively collected blind datasets provided by IVF clinics using the genetics AI model in clinical practice. Of these images, a total of 5050 images of embryos on Day 5 of in vitro culture were used for the development of the AI model. These Day 5 images were provided for 2438 consecutively treated women who had undergone IVF procedures in the USA between 2011 and 2020. The remaining images were used for evaluation of performance in different settings, or otherwise excluded for not matching the inclusion criteria. PARTICIPANTS/MATERIALS, SETTING, METHODS: The genetics AI model was trained using static 2-dimensional optical light microscope images of Day 5 blastocysts with linked genetic metadata obtained from PGT-A. The endpoint was ploidy status (euploid or aneuploid) based on PGT-A results. Predictive accuracy was determined by evaluating sensitivity (correct prediction of euploid), specificity (correct prediction of aneuploid) and overall accuracy. The Matthew correlation coefficient and receiver-operating characteristic curves and precision-recall curves (including AUC values), were also determined. Performance was also evaluated using correlation analyses and simulated cohort studies to evaluate ranking ability for euploid enrichment. MAIN RESULTS AND THE ROLE OF CHANCE: Overall accuracy for the prediction of euploidy on a blind test dataset was 65.3%, with a sensitivity of 74.6%. When the blind test dataset was cleansed of poor quality and mislabeled images, overall accuracy increased to 77.4%. This performance may be relevant to clinical situations where confounding factors, such as variability in PGT-A testing, have been accounted for. There was a significant positive correlation between AI score and the proportion of euploid embryos, with very high scoring embryos (9.0-10.0) twice as likely to be euploid than the lowest-scoring embryos (0.0-2.4). When using the genetics AI model to rank embryos in a cohort, the probability of the top-ranked embryo being euploid was 82.4%, which was 26.4% more effective than using random ranking, and ∼13-19% more effective than using the Gardner score. The probability increased to 97.0% when considering the likelihood of one of the top two ranked embryos being euploid, and the probability of both top two ranked embryos being euploid was 66.4%. Additional analyses showed that the AI model generalized well to different patient demographics and could also be used for the evaluation of Day 6 embryos and for images taken using multiple time-lapse systems. Results suggested that the AI model could potentially be used to differentiate mosaic embryos based on the level of mosaicism. LIMITATIONS, REASONS FOR CAUTION: While the current investigation was performed using both retrospectively and prospectively collected data, it will be important to continue to evaluate real-world use of the genetics AI model. The endpoint described was euploidy based on the clinical outcome of PGT-A results only, so predictive accuracy for genetic status in utero or at birth was not evaluated. Rebiopsy studies of embryos using a range of PGT-A methods indicated a degree of variability in PGT-A results, which must be considered when interpreting the performance of the AI model. WIDER IMPLICATIONS OF THE FINDINGS: These findings collectively support the use of this genetics AI model for the evaluation of embryo ploidy status in a clinical setting. Results can be used to aid in prioritizing and enriching for embryos that are likely to be euploid for multiple clinical purposes, including selection for transfer in the absence of alternative genetic testing methods, selection for cryopreservation for future use or selection for further confirmatory PGT-A testing, as required. STUDY FUNDING/COMPETING INTEREST(S): Life Whisperer Diagnostics is a wholly owned subsidiary of the parent company, Presagen Holdings Pty Ltd. Funding for the study was provided by Presagen with grant funding received from the South Australian Government: Research, Commercialisation, and Startup Fund (RCSF). 'In kind' support and embryology expertise to guide algorithm development were provided by Ovation Fertility. 'In kind' support in terms of computational resources provided through the Amazon Web Services (AWS) Activate Program. J.M.M.H., D.P. and M.P. are co-owners of Life Whisperer and Presagen. S.M.D., M.A.D. and T.V.N. are employees or former employees of Life Whisperer. S.M.D, J.M.M.H, M.A.D, T.V.N., D.P. and M.P. are listed as inventors of patents relating to this work, and also have stock options in the parent company Presagen. M.V. sits on the advisory board for the global distributor of the technology described in this study and also received support for attending meetings. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Diagnóstico Pré-Implantação , Aneuploidia , Inteligência Artificial , Austrália , Blastocisto/patologia , Feminino , Fertilização in vitro/métodos , Humanos , Gravidez , Diagnóstico Pré-Implantação/métodos , Probabilidade , Estudos Retrospectivos
5.
Sci Rep ; 12(1): 8888, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35614106

RESUMO

Training on multiple diverse data sources is critical to ensure unbiased and generalizable AI. In healthcare, data privacy laws prohibit data from being moved outside the country of origin, preventing global medical datasets being centralized for AI training. Data-centric, cross-silo federated learning represents a pathway forward for training on distributed medical datasets. Existing approaches typically require updates to a training model to be transferred to a central server, potentially breaching data privacy laws unless the updates are sufficiently disguised or abstracted to prevent reconstruction of the dataset. Here we present a completely decentralized federated learning approach, using knowledge distillation, ensuring data privacy and protection. Each node operates independently without needing to access external data. AI accuracy using this approach is found to be comparable to centralized training, and when nodes comprise poor-quality data, which is common in healthcare, AI accuracy can exceed the performance of traditional centralized training.


Assuntos
Aprendizado de Máquina , Privacidade , Coleta de Dados , Atenção à Saúde , Aprendizagem
6.
Sci Rep ; 11(1): 18005, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504205

RESUMO

The detection and removal of poor-quality data in a training set is crucial to achieve high-performing AI models. In healthcare, data can be inherently poor-quality due to uncertainty or subjectivity, but as is often the case, the requirement for data privacy restricts AI practitioners from accessing raw training data, meaning manual visual verification of private patient data is not possible. Here we describe a novel method for automated identification of poor-quality data, called Untrainable Data Cleansing. This method is shown to have numerous benefits including protection of private patient data; improvement in AI generalizability; reduction in time, cost, and data needed for training; all while offering a truer reporting of AI performance itself. Additionally, results show that Untrainable Data Cleansing could be useful as a triage tool to identify difficult clinical cases that may warrant in-depth evaluation or additional testing to support a diagnosis.

7.
Hum Reprod ; 35(4): 770-784, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32240301

RESUMO

STUDY QUESTION: Can an artificial intelligence (AI)-based model predict human embryo viability using images captured by optical light microscopy? SUMMARY ANSWER: We have combined computer vision image processing methods and deep learning techniques to create the non-invasive Life Whisperer AI model for robust prediction of embryo viability, as measured by clinical pregnancy outcome, using single static images of Day 5 blastocysts obtained from standard optical light microscope systems. WHAT IS KNOWN ALREADY: Embryo selection following IVF is a critical factor in determining the success of ensuing pregnancy. Traditional morphokinetic grading by trained embryologists can be subjective and variable, and other complementary techniques, such as time-lapse imaging, require costly equipment and have not reliably demonstrated predictive ability for the endpoint of clinical pregnancy. AI methods are being investigated as a promising means for improving embryo selection and predicting implantation and pregnancy outcomes. STUDY DESIGN, SIZE, DURATION: These studies involved analysis of retrospectively collected data including standard optical light microscope images and clinical outcomes of 8886 embryos from 11 different IVF clinics, across three different countries, between 2011 and 2018. PARTICIPANTS/MATERIALS, SETTING, METHODS: The AI-based model was trained using static two-dimensional optical light microscope images with known clinical pregnancy outcome as measured by fetal heartbeat to provide a confidence score for prediction of pregnancy. Predictive accuracy was determined by evaluating sensitivity, specificity and overall weighted accuracy, and was visualized using histograms of the distributions of predictions. Comparison to embryologists' predictive accuracy was performed using a binary classification approach and a 5-band ranking comparison. MAIN RESULTS AND THE ROLE OF CHANCE: The Life Whisperer AI model showed a sensitivity of 70.1% for viable embryos while maintaining a specificity of 60.5% for non-viable embryos across three independent blind test sets from different clinics. The weighted overall accuracy in each blind test set was >63%, with a combined accuracy of 64.3% across both viable and non-viable embryos, demonstrating model robustness and generalizability beyond the result expected from chance. Distributions of predictions showed clear separation of correctly and incorrectly classified embryos. Binary comparison of viable/non-viable embryo classification demonstrated an improvement of 24.7% over embryologists' accuracy (P = 0.047, n = 2, Student's t test), and 5-band ranking comparison demonstrated an improvement of 42.0% over embryologists (P = 0.028, n = 2, Student's t test). LIMITATIONS, REASONS FOR CAUTION: The AI model developed here is limited to analysis of Day 5 embryos; therefore, further evaluation or modification of the model is needed to incorporate information from different time points. The endpoint described is clinical pregnancy as measured by fetal heartbeat, and this does not indicate the probability of live birth. The current investigation was performed with retrospectively collected data, and hence it will be of importance to collect data prospectively to assess real-world use of the AI model. WIDER IMPLICATIONS OF THE FINDINGS: These studies demonstrated an improved predictive ability for evaluation of embryo viability when compared with embryologists' traditional morphokinetic grading methods. The superior accuracy of the Life Whisperer AI model could lead to improved pregnancy success rates in IVF when used in a clinical setting. It could also potentially assist in standardization of embryo selection methods across multiple clinical environments, while eliminating the need for complex time-lapse imaging equipment. Finally, the cloud-based software application used to apply the Life Whisperer AI model in clinical practice makes it broadly applicable and globally scalable to IVF clinics worldwide. STUDY FUNDING/COMPETING INTEREST(S): Life Whisperer Diagnostics, Pty Ltd is a wholly owned subsidiary of the parent company, Presagen Pty Ltd. Funding for the study was provided by Presagen with grant funding received from the South Australian Government: Research, Commercialisation and Startup Fund (RCSF). 'In kind' support and embryology expertise to guide algorithm development were provided by Ovation Fertility. J.M.M.H., D.P. and M.P. are co-owners of Life Whisperer and Presagen. Presagen has filed a provisional patent for the technology described in this manuscript (52985P pending). A.P.M. owns stock in Life Whisperer, and S.M.D., A.J., T.N. and A.P.M. are employees of Life Whisperer.


Assuntos
Inteligência Artificial , Microscopia , Austrália , Feminino , Fertilização in vitro , Humanos , Gravidez , Estudos Retrospectivos
9.
Diabet Med ; 37(9): 1463-1470, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31418916

RESUMO

AIM: To assess the clinical performance and patient acceptance of HemaSpot™ blood collection devices as an alternative blood collection method. METHODS: Adult men and women with any type of diabetes, routinely carrying out self-monitoring of blood glucose were recruited (n = 128). Participants provided a venous blood sample and prepared two HemaSpot dried blood spots, one at clinics and one at home. HbA1c analysis was by Tosoh G8 high-performance liquid chromatography. Participants also completed a questionnaire. RESULTS: Strong linear relationships been HbA1c levels in dried blood spots and venous blood were observed and a linear model was fitted to the data. Time between dried blood spot preparation and testing did not impact the model. Participants were accepting of the approach: 69.2% would use this system if available and 60.7% would be more likely to use this system than going to their general practitioner. CONCLUSIONS: The combination of a robust desiccating dried blood spot device, home sample preparation and return by post produces HbA1c data that support the use of a time-independent linear calibration of dried blood spot to venous blood HbA1c . A robust remote sample collection service would be valuable to people living with diabetes in urban areas who are working or house-bound as well as those living in remote or rural locations.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Teste em Amostras de Sangue Seco/métodos , Hemoglobinas Glicadas/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Química do Sangue/métodos , Coleta de Amostras Sanguíneas , Cromatografia Líquida de Alta Pressão , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Reprodutibilidade dos Testes , Autoteste , Adulto Jovem
10.
Sci Rep ; 8(1): 6697, 2018 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-29686361

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

11.
Sci Rep ; 7(1): 1903, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28507322

RESUMO

The expanding global distribution of multi-resistant Klebsiella pneumoniae demands faster antimicrobial susceptibility testing (AST) to guide antibiotic treatment. Current ASTs rely on time-consuming differentiation of resistance and susceptibility after initial isolation of bacteria from a clinical specimen. Here we describe a flow cytometry workflow to determine carbapenem susceptibility from bacterial cell characteristics in an international K. pneumoniae isolate collection (n = 48), with a range of carbapenemases. Our flow cytometry-assisted susceptibility test (FAST) method combines rapid qualitative susceptible/non-susceptible classification and quantitative MIC measurement in a single process completed shortly after receipt of a primary isolate (54 and 158 minutes respectively). The qualitative FAST results and FAST-derived MIC (MICFAST) correspond closely with broth microdilution MIC (MICBMD, Matthew's correlation coefficient 0.887), align with the international AST standard (ISO 200776-1; 2006) and could be used for rapid determination of antimicrobial susceptibility in a wider range of Gram negative and Gram positive bacteria.

13.
Neurol Res Int ; 2016: 6254092, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27800180

RESUMO

Research on the implications of anxiety in Parkinson's disease (PD) has been neglected despite its prevalence in nearly 50% of patients and its negative impact on quality of life. Previous reports have noted that neuropsychiatric symptoms impair cognitive performance in PD patients; however, to date, no study has directly compared PD patients with and without anxiety to examine the impact of anxiety on cognitive impairments in PD. This study compared cognitive performance across 50 PD participants with and without anxiety (17 PDA+; 33 PDA-), who underwent neurological and neuropsychological assessment. Group performance was compared across the following cognitive domains: simple attention/visuomotor processing speed, executive function (e.g., set-shifting), working memory, language, and memory/new verbal learning. Results showed that PDA+ performed significantly worse on the Digit Span forward and backward test and Part B of the Trail Making Task (TMT-B) compared to the PDA- group. There were no group differences in verbal fluency, logical memory, or TMT-A performance. In conclusion, anxiety in PD has a measurable impact on working memory and attentional set-shifting.

14.
Gait Posture ; 49: 431-436, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27513741

RESUMO

Previous research has shown that anxiety in Parkinson's disease (PD) is associated with freezing of gait (FOG), and may even contribute to the underlying mechanism. However, limited research has investigated whether PD patients with FOG (PD+FOG) have higher anxiety levels when compared directly to non-freezing PD patients (PD-NF) and moreover, how anxiety might contribute to FOG. The current study evaluated whether: (i) PD+FOG have greater anxiety compared to PD-NF, and (ii) anxiety in PD is related to attentional set-shifting, in order to better understand how anxiety might be contributing to FOG. In addition, we explored whether anxiety levels differed between those PD patients with mild FOG (PD+MildFOG) compared to PD-NF. Four hundred and sixty-one patients with PD (231 PD-NF, 180 PD+FOG, 50 PD+MildFOG) were assessed using the Freezing of Gait Questionnaire item 3 (FOG-Q3), Hospital Anxiety and Depression Scale (HADS), Digit Span Test, Logical Memory Retention Test and Trail Making Tests. Compared to PD-NF, PD+FOG had significantly greater anxiety (p<0.001). PD+MildFOG, however, demonstrated similar levels of anxiety as the PD+FOG. In all patients, the severity of anxiety symptoms was significantly correlated to their degree of self-reported FOG on FOG-Q3 (p<0.001) and TMT B-A (p=0.039). Similar results were found for depression. In conclusion, these results confirm the key role played by anxiety in FOG and also suggest that anxiety might be a promising biomarker for FOG. Future research should consider whether treating anxiety with pharmacological and/or cognitive behavioural therapies at early stages of gait impairment in PD may alleviate troublesome FOG.


Assuntos
Ansiedade/complicações , Atenção , Transtornos Neurológicos da Marcha/etiologia , Doença de Parkinson/psicologia , Idoso , Ansiedade/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autorrelato , Inquéritos e Questionários
15.
Opt Express ; 23(13): 17067-76, 2015 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-26191715

RESUMO

Whispering gallery modes (WGMs) within microsphere cavities enable highly sensitive label-free detection of changes in the surrounding refractive index. This detection modality is of particular interest for biosensing applications. However, the majority of biosensing work utilizing WGMs to date has been conducted with resonators made from either silica or polystyrene, while other materials remain largely uninvestigated. By considering characteristics such as the quality factor and sensitivity of the resonator, the optimal WGM sensor design can be identified for various applications. This work explores the choice of resonator refractive index and size to provide design guidelines for undertaking refractive index biosensing using WGMs.

16.
J Laryngol Otol ; 129(6): 529-34, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26074255

RESUMO

BACKGROUND: Olfactory dysfunction is a common condition that may in some cases require imaging to investigate a potential underlying cause. OBJECTIVES: This review describes the anatomy of normal olfaction and illustrates the pathological substrates of olfactory dysfunction amenable to imaging.


Assuntos
Diagnóstico por Imagem/métodos , Transtornos do Olfato/diagnóstico por imagem , Olfato , Humanos , Radiografia
17.
Parkinsonism Relat Disord ; 20(6): 604-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24679901

RESUMO

BACKGROUND: Previous studies have associated freezing of gait in Parkinson's disease with the presence of specific phenotypic features such as mood disturbances, REM sleep behavior disorder and selective cognitive impairments. However, it is not clear whether these features are present in the earlier stages of disease or simply represent a more general pattern of progression. To investigate this issue, the current study evaluated motor, cognitive, affective and autonomic features as well as REM sleep behavior disorder in Parkinson's disease patients in the early stages of the condition. METHODS: Thirty-eight freezers and fifty-three non-freezers with disease duration of less than five years and a Hoehn and Yahr stage of less than three were included in this study. The groups were matched on a number of key disease features including age, disease duration, motor severity and dopamine dose equivalence. Furthermore, patients were assessed on measures of motor, cognitive, affective and autonomic features, as well as REM sleep behavior disorder. RESULTS: Compared to non-freezers, patients with freezing of gait had significantly more non-tremor symptoms and a selective impairment on executive functions, such as set-shifting ability and working memory. Freezers and non-freezers did not differ on measures of tremor, autonomic function, REM sleep behavior disorder, mood or more general cognition. CONCLUSION: These results suggest the pathophysiological mechanisms underlying freezing of gait in the early clinical stages of Parkinson's disease are likely to be related to specific changes in the frontostriatal pathways rather than being due to brainstem or more diffuse neuropathology.


Assuntos
Transtornos Neurológicos da Marcha/etiologia , Doença de Parkinson/complicações , Fenótipo , Idoso , Doenças do Sistema Nervoso Autônomo/etiologia , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/etiologia , Testes Neuropsicológicos , Transtorno do Comportamento do Sono REM/etiologia , Estatísticas não Paramétricas
18.
Neuroscience ; 258: 131-46, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24215977

RESUMO

Voluntary exercise (VEx) has profound effects on neural and behavioral plasticity, including recovery of CNS trauma and disease. However, the unique regional cortical adaption to VEx has not been elucidated. In a series of experiments, we first examined whether VEx would restore and retain neurotrophin levels in several cortical regions (frontal cortex [FC], retrosplenial cortex [RSC], occipital cortex [OC]) in an animal model (pyrithiamine-induced thiamine deficiency [PTD]) of the amnestic disorder Wernicke-Korsakoff syndrome. In addition, we assessed the time-dependent effect of VEx to rescue performance on a spontaneous alternation task. Following 2-weeks of VEx or stationary housing conditions (Stat), rats were behaviorally tested and brains were harvested either the day after VEx (24-h) or after an additional 2-week period (2-wk). In both control pair-fed (PF) rats and PTD rats, all neurotrophin levels (brain-derived neurotrophic factor [BDNF], nerve growth factor [NGF], and vascular endothelial growth factor) increased at the 24-h period after VEx in the FC and RSC, but not OC. Two-weeks following VEx, BDNF remained elevated in both FC and RSC, whereas NGF remained elevated in only the FC. Interestingly, VEx only recovered cognitive performance in amnestic rats when there was an additional 2-wk adaptation period after VEx. Given this unique temporal profile, Experiment 2 examined the cortical cytogenetic responses in all three cortical regions following a 2-wk adaptation period after VEx. In healthy (PF) rats, VEx increased the survival of progenitor cells in both the FC and RSC, but only increased oligodendrocyte precursor cells (OLPs) in the FC. Furthermore, VEx had a selective effect of only recovering OLPs in the FC in PTD rats. These data reveal the therapeutic potential of exercise to restore cortical plasticity in the amnestic brain, and that the FC is one of the most responsive cortical regions to VEx.


Assuntos
Amnésia/fisiopatologia , Córtex Cerebral/fisiopatologia , Atividade Motora/fisiologia , Fatores de Crescimento Neural/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Sobrevivência Celular , Análise Citogenética , Lobo Frontal/fisiopatologia , Abrigo para Animais , Masculino , Fator de Crescimento Neural/metabolismo , Lobo Occipital/fisiopatologia , Oligodendroglia/fisiologia , Piritiamina , Ratos , Ratos Sprague-Dawley , Células-Tronco/fisiologia , Deficiência de Tiamina/fisiopatologia , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
J Anim Sci ; 88(6): 2132-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20154156

RESUMO

Two experiments were conducted to investigate using alfalfa leaf meal (ALM; 22% CP, DM basis) in beef cattle diets. In Exp. 1, a total of 24 late-gestation Angus heifers (initial BW 470 +/- 9 kg) were blocked by BW, calving date, and BCS to 1 of 4 dietary treatments in a randomized complete block design. All heifers were offered a basal hay diet (7.4% CP and 67.6% NDF, DM basis). Treatments were arranged as a 2 x 2 factorial consisting of CP supplied at 100 or 112.5% of the recommended daily intake using either soybean meal (SBM) or ALM as the supplemental protein source. Treatments were fed for an average of 100 d before calving. Total DMI was unaffected by supplemental protein source, although heifers consumed more (P < 0.001) ALM supplement than SBM supplement at the expense of hay and corn. Feeding 112.5% of recommended CP to heifers increased precalving rate of BW gain (P = 0.004) and DM digestibility (P = 0.003). Protein source did not affect DM digestibility (P = 0.17). Neither supplemental protein source nor protein amount affected changes in BCS or calving traits. In Exp. 2, replicates of treatments were conducted over 2 consecutive years at 2 locations in northern Minnesota to determine the effects of including ALM in creep-fed supplements on nursing calf performance, supplement BW gain efficiency (GF; BW gain over control/supplement intake), and cow performance. Treatments were control (no supplement), ALM supplement (58% ALM, as-fed basis), or a wheat middling- and soybean hull-based supplement (MIDD). Milk intake (estimated by the weigh-suckle-weigh technique) was similar among treatments. Creep-fed calves had greater (P < 0.001) ADG than control calves, whereas calves offered MIDD tended to have greater ADG (P = 0.05) than those offered ALM (1.38 vs. 1.30 kg/d, respectively). Calves offered MIDD had greater (P < 0.001) creep feed DMI than those offered ALM (2.6 vs. 1.3 kg/d, respectively). A year x treatment interaction was noted for GF (P = 0.02). In yr 1, GF for calves offered ALM was greater (P = 0.006) than GF for calves offered MIDD, but in yr 2, there were no differences. Alfalfa leaf meal may substitute for SBM in beef heifer wintering diets and conventional creep feed ingredients. When included in creep feed diets, ALM can result in slightly less ADG and less DMI, but supplement conversion efficiency may be increased.


Assuntos
Medicago sativa/metabolismo , Ovinos/metabolismo , Animais , Animais Lactentes , Peso Corporal/fisiologia , Bovinos , Suplementos Nutricionais , Ingestão de Alimentos/fisiologia , Fezes/química , Feminino , Análise dos Mínimos Quadrados , Gravidez , Distribuição Aleatória , /metabolismo
20.
Palliat Med ; 23(3): 190-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19251834

RESUMO

The importance of evaluating systematically the effectiveness of hospice care has been noted for at least 20 years. There is, however, limited evidence about whether and how the care provided to terminally ill patients by in-patient hospices in the UK differs from that provided in NHS hospitals. In this article, we, therefore, present a comparison of hospice in-patient care and hospital care for cancer patients in the UK, from the perspective of bereaved relatives who had experienced both types of care during the last 3 months of the patient's life. The Office of National Statistics drew a random sample of 800 deaths in South London in 2002, and sent the person who registered the death (the informant) a Views of Informal Carers - Evaluation of Services (VOICES) questionnaire 3-9 months after the death, with up to two reminders. There was a response rate of 48%. For this analysis, 40 cancer patients whose informant reported both a hospice in-patient admission and a hospital admission in the last 3 months of life were identified. Informants answered the same questions about each admission and responses on these were compared. There were statistically significant differences between respondents' views of hospice and hospital care on eight out of 13 variables measuring aspects of satisfaction with care, with a trend towards statistical significance on a further two: in all cases respondents rated hospice care more positively than hospital care. There were no differences in the experience of pain and breathlessness in the two settings, but respondents rated pain control by the hospice as more effective. In comparison to hospital care, from the perspective of bereaved relatives, hospice in-patient care provided better pain control, better communication with patients and families, and better medical, nursing and personal care, which treated the patient with more dignity. Further research is needed to confirm these findings using a wider sample of in-patient hospices in the UK and including the perspectives of patients. Providing high quality care for terminally ill patients in acute hospitals remains an important challenge.


Assuntos
Cuidadores/psicologia , Hospitais/normas , Satisfação do Paciente , Qualidade da Assistência à Saúde/normas , Assistência Terminal/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Atitude do Pessoal de Saúde , Luto , Tomada de Decisões , Feminino , Pesquisas sobre Atenção à Saúde , Cuidados Paliativos na Terminalidade da Vida/normas , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/mortalidade , Neoplasias/terapia , Papel do Profissional de Enfermagem , Avaliação de Processos e Resultados em Cuidados de Saúde , Manejo da Dor , Relações Profissional-Família , Qualidade da Assistência à Saúde/tendências , Medicina Estatal , Inquéritos e Questionários , Assistência Terminal/organização & administração , Assistência Terminal/psicologia , Reino Unido
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