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1.
Sci Adv ; 5(9): eaaw5978, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31555728

RESUMO

The ability to convert between molecular spin states is of utmost importance in materials chemistry. Förster-type energy transfer is based on dipole-dipole interactions and can therefore theoretically be used to convert between molecular spin states. Here, a molecular dyad that is capable of transferring energy from an excited triplet state to an excited singlet state is presented. The rate of conversion between these states was shown to be 36 times faster than the rate of emission from the isolated triplet state. This dyad provides the first solid proof that Förster-type triplet-to-singlet energy transfer is possible, revealing a method to increase the rate of light extraction from excited triplet states.

2.
Sports Med ; 48(3): 539-583, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29098658

RESUMO

BACKGROUND: Understanding soccer players' match-related fatigue and recovery profiles likely helps with developing conditioning programs that increase team performance and reduce injuries and illnesses. In order to improve match recovery (the return-to-play process and ergogenic interventions) it is also pivotal to determine if match simulation protocols and actual match-play lead to similar responses. OBJECTIVES: (1) To thoroughly describe the development of fatigue during actual soccer match play and its recovery time course in terms of physiological, neuromuscular, technical, biochemical and perceptual responses, and (2) to determine similarities of recovery responses between actual competition (11 vs. 11) and match simulations. METHODS: A first screening phase consisted of a systematic search on PubMed (MEDLINE) and SportDiscus databases until March 2016. Inclusion criteria were: longitudinal study with soccer players; match or validated protocol; duration > 45 min; and published in English. RESULTS: A total of 77 eligible studies (n = 1105) were used to compute 1196 effect sizes (ES). Half-time assessments revealed small to large alterations in immunological parameters (e.g. leukocytes, ES = 1.9), a moderate decrement in insulin concentration (ES = - 0.9) and a small to moderate impairment in lower-limb muscle function (ES = - 0.5 to - 0.7) and physical performance measures (e.g. linear sprint, ES = - 0.3 to - 1.0). All the systematically analyzed fatigue-related markers were substantially altered at post-match. Hamstrings force production capacity (ES = - 0.7), physical performance (2-4%, ES = 0.3-0.5), creatine kinase (CK, ES = 0.4), well-being (ES = 0.2-0.4) and delayed onset muscle soreness (DOMS, ES = 0.6-1.3) remained substantially impaired at G + 72 h. Compared to simulation protocols, 11 vs. 11 match format (CK, ES = 1.8) induced a greater magnitude of change in muscle damage (i.e. CK, ES = 1.8 vs. 0.7), inflammatory (IL-6, ES = 2.6 vs. 1.1) and immunological markers and DOMS (ES = 1.5 vs. 0.7) than simulation protocols at post-assessments. Neuromuscular performances at post-match did not differ between protocols. CONCLUSION: While some parameters are fully recovered (e.g. hormonal and technical), our systematic review shows that a period of 72 h post-match play is not long enough to completely restore homeostatic balance (e.g. muscle damage, physical and well-being status). The extent of the recovery period post-soccer game cannot consist of a 'one size fits all approach'. Additionally, the 'real match' (11 vs. 11 format) likely induces greater magnitudes of perceptual (DOMS) and biochemical alterations (e.g. muscle damage), while neuromuscular alterations were essentially similar. Overall, coaches must adjust the structure and content of the training sessions during the 72-h post-match intervention to effectively manage the training load within this time-frame.


Assuntos
Desempenho Atlético , Fadiga Muscular/fisiologia , Força Muscular/fisiologia , Futebol/lesões , Feminino , Humanos , Masculino , Atividade Motora/fisiologia , Contração Muscular/fisiologia , Mialgia/fisiopatologia , Futebol/fisiologia
3.
J Nutr Health Aging ; 21(4): 421-428, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28346569

RESUMO

OBJECTIVE: To assess the efficacy and safety of a single cholecalciferol loading protocol in nursing home (NH) residents taking no VitD supplementation at regular basis. DESIGN: Randomized single-blind controlled study. SETTING: One NH. PARTICIPANTS: All residents. INTERVENTION: From March 21st to May 19th, 2015, NH residents were randomly assigned to either 4x100'000IU to be taken every 2 weeks (treatment group) or an individualized regimen according to baseline 25(OH)VitD level (control group). MEASUREMENTS: 25(OH)VitD, calcium, phosphorus, parathyroid hormone, alkaline phosphatase, and creatinine serum levels were centrally measured at day 7 after the last dose in both groups, and at baseline in the control group. RESULTS: 111 residents (mean age 85.1±6.7 years) were randomized to the treatment (N=53) or the control group (N=58). No significant difference in terms of demographic characteristics, risk for osteoporosis, and past history of VitD supplementation was measured. At baseline, 37.9%, 25.5% and 5.2% were respectively sub-optimal, insufficient, and deficient for VitD. Whatever the study group, at the 7th day after the last dose of cholecalciferol, 100% of residents reached serum values ≥20ng/mL (p value for non-inferiority <0.001 and p value for superiority p=1.00) and 93.6 vs. 88.2% reached values ≥30ng/mL in the treatment and control group respectively (p value for non-inferiority <0.01 and p value for superiority p=0.48). While mean value was higher in the treatment group (50.2±615.4 vs. 35.8±66.5ng/mL; p<0.0001), none of participants have seen their value >150 ng/mL. Not any biological adverse effects was measured. CONCLUSION: This study confirmed that a single loading protocol is at least as effective and safe as tailored regimen in terms of the ability to rapidly normalize 25(OH)VitD values. The often required dosage of 25(OH)VitD is reasonably not necessary to initiate VitD supplementation protocol in this vulnerable population.


Assuntos
Calcifediol/sangue , Colecalciferol/administração & dosagem , Colecalciferol/uso terapêutico , Casas de Saúde , Deficiência de Vitamina D/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Cálcio/sangue , Creatinina/sangue , Suplementos Nutricionais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Fósforo/sangue , Método Simples-Cego , Deficiência de Vitamina D/sangue
4.
J Clin Virol ; 43(2): 216-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18619898

RESUMO

BACKGROUND: Although human cytomegalovirus (HCMV) infection in infants has been associated with liver disease, the role of HCMV in infants presenting with prolonged neonatal jaundice is unclear as this clinical picture can be caused by a broad spectrum of underlying conditions. OBJECTIVES: This study aimed to determine a possible role for HCMV infection in infants with prolonged cholestatic neonatal jaundice that could facilitate the appropriate use of diagnostic assays and specific treatment in this condition. STUDY DESIGN: HCMV immunohistochemical staining was performed on liver biopsy specimens received for histopathological examination from 85 infants (mean age 3 months) with a clinical history of prolonged neonatal jaundice. HCMV serology was also performed. RESULTS: One infant with a histological diagnosis of HCMV hepatitis was also positive by immunohistochemical staining, while all other tissue specimens were negative for HCMV. HCMV IgG was positive in 92.3% and HCMV IgM in 39.7% of the infants (n=78). CONCLUSIONS: The serological results confirm the ubiquitous nature of HCMV with many primary infections occurring within the first year of life. Despite this, HCMV hepatitis was uncommon in this cohort.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus/imunologia , Icterícia Obstrutiva/complicações , Biópsia , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Feminino , Hepatite Viral Humana/diagnóstico , Hepatite Viral Humana/epidemiologia , Hepatite Viral Humana/imunologia , Hepatite Viral Humana/virologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Imuno-Histoquímica , Lactente , Fígado/patologia , Fígado/virologia , Masculino
5.
Cell Mol Life Sci ; 62(9): 955-70, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15868099

RESUMO

Dynamic assembly of actin filaments generates the forces supporting cell motility. Several recent biochemical and genetic studies have revealed a plethora of different actin binding proteins whose coordinated activity regulates the turnover of actin filaments, thus controlling a variety of actin-based processes, including cell migration. Additionally, emerging evidence is highlighting a scenario whereby the same basic set of actin regulatory proteins is also the convergent node of different signaling pathways emanating from extracellular stimuli, like those from receptor tyrosine kinases. Here, we will focus on the molecular mechanisms of how the machinery of actin polymerization functions and is regulated, in a signaling-dependent mode, to generate site-directed actin assembly leading to cell motility.


Assuntos
Citoesqueleto de Actina/fisiologia , Movimento Celular/fisiologia , Transdução de Sinais/fisiologia , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Animais , Proteínas do Citoesqueleto/fisiologia , Humanos , Proteínas dos Microfilamentos/fisiologia , Modelos Biológicos , Pseudópodes/metabolismo , Proteínas rac de Ligação ao GTP/fisiologia , Proteínas rho de Ligação ao GTP/fisiologia
6.
Semin Speech Lang ; 17(1): 73-90, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8857366

RESUMO

This article reports findings from interviews with 20 parents about their experiences in obtaining services for their ADHD children in school systems. Grounded theory methods were used to analyze data at both individual and organizational levels. Parents saw school personnel as varying widely in their knowledge about ADHD and their acceptance of its associated problems. At the individual level, parents felt that they had to educate a succession of different school personnel each year. At the organizational level, they had to work actively to obtain continuity of services for their children from year to year and school to school, but for most parents, this outcome was desired more often than realized. On the whole, parents perceived schools as having failed to respond adequately to their children's educational needs.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Pais , Instituições Acadêmicas , Ensino , Adolescente , Idade de Início , Criança , Pré-Escolar , Humanos , Masculino , Recursos Humanos
7.
J Hand Surg Am ; 16(4): 708-11, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1880370

RESUMO

To assess the value of ultrasound in imaging the plantaris tendon, ultrasounds were done on 26 legs in 25 patients who had a variety of surgical procedures on the posterior leg. Eighteen ultrasounds were done and interpreted before operation and eight after operation by a radiologist. The sonographic results were compared with the status of the plantaris as determined at surgery. The plantaris was present in 21 of 23 patients for a prevalence of 91%. Eighteen plantaris tendons were well visualized on ultrasound for a sensitivity of 86%. Of the three false-negative results, two occurred with thinned plantaris tendons that were less than 2 mm thick and hence considered inadequate for grafting. Therefore, the sensitivity for detecting a tendon suitable for grafting was 95%. All patients with positive studies had a plantaris tendon present for a specificity of 100%. A learning curve for the radiologist was demonstrated. Ultrasound appears to be effective in the preoperative imaging of the plantaris tendon.


Assuntos
Perna (Membro)/diagnóstico por imagem , Tendões/transplante , Tendão do Calcâneo/diagnóstico por imagem , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Cuidados Pré-Operatórios , Sensibilidade e Especificidade , Tendões/anormalidades , Tendões/diagnóstico por imagem , Ultrassonografia
8.
Multivariate Behav Res ; 26(4): 765-92, 1991 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26751030

RESUMO

The application of item response theory (IRT) models requires the identification of the data's dimensionality. A popular method for determining the number of latent dimensions is the factor analysis of a correlation matrix. Unlike factor analysis, which is based on a linear model, IRT assumes a nonlinear relationship between item performance and ability. Because multidimensional scaling (MDS) assumes a monotonic relationship this method may be useful for the assessment of a data set's dimensionality for use with IRT models. This study compared MDS, exploratory and confirmatory factor analysis (EFA and CFA, respectively) in the assessment of the dimensionality of data sets which had been generated to be either one- or two-dimensional. In addition, the data sets differed in the degree of interdimensional correlation and in the number of items defining a dimension. Results showed that MDS and CFA were able to correctly identify the number of latent dimensions for all data sets. In general, EFA was able to correctly identify the data's dimensionality, except for data whose interdimensional correlation was high.

9.
Arch Mal Coeur Vaiss ; 83 Spec No 1: 21-4, 1990 Feb.
Artigo em Francês | MEDLINE | ID: mdl-2108642

RESUMO

Coronary recanalisation rate is one of the parameters utilized to evaluate the effectiveness of a thrombolytic agent. This parameter can only be measured when the occlusion and reopening of the coronary artery involved are demonstrated by angiography. Moreover, this type of study enables the kinetics of drug activity to be accurately determined. When injected intravenously in doses of 30 units less than four hours after the onset of chest pain and when studied by this method, Eminase produces recanalisation in more than 60 per 100 of the cases. The time elapsed between injection and action is 45 minutes on average. The risk of early reocclusion is low (about 5%). The recanalisation rate obtained with Eminase is similar to that obtained with intracoronary streptokinase.


Assuntos
Fibrinolíticos/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Reperfusão Miocárdica , Plasminogênio/uso terapêutico , Estreptoquinase/uso terapêutico , Anistreplase , Angiografia Coronária , Fibrinolíticos/administração & dosagem , Humanos , Injeções Intravenosas , Plasminogênio/administração & dosagem , Estreptoquinase/administração & dosagem , Fatores de Tempo
10.
J Nucl Med ; 26(11): 1278-82, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-4056924

RESUMO

A case of positive Meckel's diverticulum scan caused by a leiomyoma of the terminal ileum is reported. The early appearance of activity on the perfusion study aided in recognition of a false-positive scan.


Assuntos
Neoplasias do Íleo/diagnóstico por imagem , Íleo/diagnóstico por imagem , Leiomioma/diagnóstico por imagem , Divertículo Ileal/diagnóstico por imagem , Diagnóstico Diferencial , Reações Falso-Positivas , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia
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