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1.
Med Teach ; : 1-7, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37949084

RESUMO

PURPOSE: Medical education relies on clinical supervision for critical functions, including trainee assessment and ensuring patient safety. Yet, there is substantial variance in supervision, which has led to calls for a shared definition of the concept and guidelines to inform practice. AMEE Guide No. 27 provided these desired elements and is highly cited, suggesting that translation and utilization of the Guide's knowledge is suboptimal. This study investigates utilization by systematically characterizing citations to the Guide and by describing translation of its recommendations in relation to supervision. MATERIALS AND METHODS: Citations were identified using Web of Science, Scopus, and Google Scholar. The authors coded all citations and conducted a subanalysis of studies specific to supervision. RESULTS: 583 studies were identified; 268 met inclusion criteria for general analysis of which 167 studies were further analyzed. Most studies reiterated the Guide's characterization of effective supervision, but few demonstrate how these recommendations inform innovations in supervisory practice. CONCLUSION: Translation of the Guide's recommendations regarding clinical supervision appears limited. Future research should consider the extent of knowledge translation occurring in clinical supervision literature as well as AMEE Guides. Increased attention to knowledge translation in medical education may benefit the distribution of similar knowledge products.

2.
Faraday Discuss ; 187: 521-37, 2016 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-27048927

RESUMO

Several proof-of-concept studies on the vibrational spectroscopy of biofluids have demonstrated that the methodology has promising potential as a clinical diagnostic tool. However, these studies also show that there is a lack of a standardised protocol in sample handling and preparation prior to spectroscopic analysis. One of the most important sources of analytical errors is the pre-analytical phase. For the technique to be translated into clinics, it is clear that a very strict protocol needs to be established for such biological samples. This study focuses on some of the aspects of the pre-analytical phase in the development of the high-throughput Fourier Transform Infrared (FTIR) spectroscopy of some of the most common biofluids such as serum, plasma and bile. Pre-analytical considerations that can impact either the samples (solvents, anti-coagulants, freeze-thaw cycles…) and/or spectroscopic analysis (sample preparation such as drying, deposit methods, volumes, substrates, operators dependence…) and consequently the quality and the reproducibility of spectral data will be discussed in this report.


Assuntos
Métodos Analíticos de Preparação de Amostras/métodos , Métodos Analíticos de Preparação de Amostras/normas , Líquidos Corporais/química , Líquidos Corporais/diagnóstico por imagem , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/normas , Anticoagulantes/química , Bile/química , Congelamento , Humanos , Plasma/química , Reprodutibilidade dos Testes , Soro/química , Solventes/química , Vibração
3.
Br J Anaesth ; 117 Suppl 1: i87-i91, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27130269

RESUMO

BACKGROUND: Developing expertise in flexible bronchoscopy is limited by inadequate opportunities to train on difficult airways. The new ORSIM bronchoscopy simulator aims to address this by creating virtual patients with difficult airways. This study aims to provide evidence on the validity and reliability of the ORSIM for assessment of subjects on both normal and abnormal airway simulations. METHODS: Novice, trainee, and expert subjects performed seven simulations of varying difficulty and scored the perceived difficulty for each. Time to completion was measured. Three blinded raters independently scored videos of each subject's performance. We measured inter-rater agreement and the difference in raters' scores between subject groups. RESULTS: We recruited 28 study subjects, generating 196 videos for analysis. Expert subjects consistently completed the scenarios faster than novices. Overall performance scores showed significant differences between subject groups (P<0.0001). Inter-rater reliability of scores was >0.8. CONCLUSIONS: Our results provide initial evidence on the validity and reliability of the ORSIM bronchoscopy simulator, supporting its potential value in training and assessment.


Assuntos
Anestesiologia/educação , Broncoscopia/educação , Competência Clínica , Educação Médica Continuada/métodos , Broncoscópios , Broncoscopia/instrumentação , Broncoscopia/normas , Simulação por Computador , Tecnologia de Fibra Óptica/educação , Humanos , Nova Zelândia , Variações Dependentes do Observador , Reprodutibilidade dos Testes
4.
Anal Methods ; 13(2): 157-168, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33284291

RESUMO

Infections and sepsis represent a growing global burden. There is a widespread clinical need for a rapid, high-throughput and sensitive technique for the diagnosis of infections and detection of invading pathogens and the presence of sepsis. Current diagnostic methods primarily consist of laboratory-based haematology, biochemistry and microbiology that are time consuming, labour- and resource-intensive, and prone to both false positive and false negative results. Current methods are insufficient for the increasing demands on healthcare systems, causing delays in diagnosis and initiation of treatment, due to the intrinsic time delay in sample preparation, measurement, and analysis. Vibrational spectroscopic techniques can overcome these limitations by providing a rapid, label-free and low-cost method for blood analysis, with limited sample preparation required, potentially revolutionising clinical diagnostics by producing actionable results that enable early diagnosis, leading to improved patient outcomes. This review will discuss the challenges associated with the diagnosis of infections and sepsis, primarily within the UK healthcare system. We will consider the clinical potential of spectroscopic point-of-care technologies to enable blood analysis in the primary-care setting.


Assuntos
Testes Diagnósticos de Rotina , Sepse , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Sepse/diagnóstico
5.
Analyst ; 135(5): 887-94, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20419236

RESUMO

Interest in developing robust, quicker and easier diagnostic tests for cancer has lead to an increased use of Fourier transform infrared (FTIR) spectroscopy to meet that need. In this study we present the use of different experimental modes of infrared spectroscopy to investigate the RWPE human prostate epithelial cell line family which are derived from the same source but differ in their mode of transformation and their mode of invasive phenotype. Importantly, analysis of the infrared spectra obtained using different experimental modes of infrared spectroscopy produces similar results. The RWPE family of cell lines can be separated into groups based upon the method of cell transformation rather than the resulting invasiveness/aggressiveness of the cell line. The study also demonstrates the possibility of using a genetic algorithm as a possible standardised pre-processing step and raises the important question of the usefulness of cell lines to create a biochemical model of prostate cancer progression.


Assuntos
Linhagem Celular Transformada , Neoplasias da Próstata/patologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Algoritmos , Análise Discriminante , Células Epiteliais/citologia , Marcadores Genéticos , Humanos , Masculino , Invasividade Neoplásica , Análise de Componente Principal , Próstata/citologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética
6.
BJS Open ; 4(4): 554-562, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32424976

RESUMO

BACKGROUND: Vibrational spectroscopy (VS) is a minimally invasive tool for analysing biological material to detect disease. This study aimed to review its application to human blood for cancer diagnosis. METHODS: A systematic review was undertaken using a keyword electronic database search (MEDLINE, Embase, PubMed, TRIP and Cochrane Library), with all original English-language manuscripts examining the use of vibrational spectral analysis of human blood for cancer detection. Studies involving fewer than 75 patients in the cancer or control group, animal studies, or where the primary analyte was not blood were excluded. RESULTS: From 1446 results, six studies (published in 2010-2018) examining brain, bladder, oral, breast, oesophageal and hepatic cancer met the criteria for inclusion, with a total population of 2392 (1316 cancer, 1076 control; 1476 men, 916 women). For cancer detection, reported mean sensitivities in each included study ranged from 79·3 to 98 per cent, with specificities of 82·8-95 per cent and accuracies between 81·1 and 97·1 per cent. Heterogeneity in reporting strategies, methods and outcome measures made meta-analysis inappropriate. CONCLUSION: VS shows high potential for cancer diagnosis, but until there is agreement on uniform standard reporting methods and studies with adequate sample size for valid classification models have been performed, its value in clinical practice will remain uncertain.


la espectroscopia vibracional (vibrational spectroscopy, VS) es un dispositivo mínimamente invasivo para analizar material biológico y detectar enfermedad. Este estudio se propuso revisar su aplicación en la sangre humana para el diagnóstico de cáncer. MÉTODOS: Se llevó a cabo una revisión sistemática utilizando una búsqueda con palabras claves en bases de datos electrónicas (MEDLINE, EMBASE, PubMed, TRIP, Cochrane Library), de todos los manuscritos originales publicados en inglés que examinaban la utilización del análisis espectral vibracional de la sangre humana para la detección del cáncer. Se excluyeron estudios que incluían menos de 75 pacientes en los grupos cáncer/control, estudios en animales o cuando la muestra principal no fuera la sangre. RESULTADOS: De los 1.446 resultados, 6 estudios publicados en 2010-2018, y que examinaban cánceres del cerebro, vejiga, oral, mama, esófago e hígado cumplieron los criterios de inclusión, con una población total de 2.506 casos (1.316 cánceres, 1.076 controles; 1.476 varones, 915 mujeres). Para la detección del cáncer, las sensibilidades medias descritas en cada uno de los estudios incluidos variaron entre 79,3-98,0%, con especificidades entre 82,8-95,0%, y exactitudes diagnósticas entre 81,1% y 97,1%. La heterogeneidad en las estrategias descritas, métodos y medidas de resultados hicieron que el metaanálisis fuera inapropiado. CONCLUSIÓN: La VS muestra un alto potencial para el diagnóstico del cáncer, pero hasta que no se llegue a un acuerdo en los métodos para informar de los resultados y se hayan efectuado estudios con un tamaño muestral adecuado para una clasificación válida de los modelos, su valor en la práctica clínica sigue siendo incierto.


Assuntos
Neoplasias/diagnóstico , Análise Espectral , Humanos , Biópsia Líquida/métodos , Neoplasias/patologia
7.
Br J Cancer ; 99(11): 1859-66, 2008 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-18985044

RESUMO

Fourier transform infrared (FTIR) spectroscopy is a vibrational spectroscopic technique that uses infrared radiation to vibrate molecular bonds within the sample that absorbs it. As different samples contain different molecular bonds or different configurations of molecular bonds, FTIR allows us to obtain chemical information on molecules within the sample. Fourier transform infrared microspectroscopy in conjunction with a principal component-discriminant function analysis (PC-DFA) algorithm was applied to the grading of prostate cancer (CaP) tissue specimens. The PC-DFA algorithm is used alongside the established diagnostic measures of Gleason grading and the tumour/node/metastasis system. Principal component-discriminant function analysis improved the sensitivity and specificity of a three-band Gleason score criterion diagnosis previously reported by attaining an overall sensitivity of 92.3% and specificity of 99.4%. For the first time, we present the use of a two-band criterion showing an association of FTIR-based spectral characteristics with clinically aggressive behaviour in CaP manifest as local and/or distal spread. This paper shows the potential for the use of spectroscopic analysis for the evaluation of the biopotential of CaP in an accurate and reproducible manner.


Assuntos
Neoplasias da Próstata/patologia , Espectroscopia de Infravermelho com Transformada de Fourier , Algoritmos , Humanos , Masculino , Estadiamento de Neoplasias , Sensibilidade e Especificidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
8.
Appl Surf Sci ; 255(4): 1190-1192, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19430585

RESUMO

With the chemical imaging capability of ToF-SIMS, biological molecules are identified and localized in membranes without any chemical labels. We have developed a model membrane system made with supported Langmuir-Blodgett (LB) monolayers. This simplified model can be used with different combinations of molecules to form a membrane, and thus represents a bottom-up approach to study individual lipid-lipid or lipid-protein interactions. We have used ternary mixtures of sphingomyelin (SM), phosphatidylcholine (PC), and cholesterol (CH) in the model membrane to study the mechanism of domain formation and interactions between phospholipids and cholesterol. Domain structures are observed only when the acyl chain saturation is different for SM and PC in the mixture. The saturated lipid, whether it is SM or PC, is found to be localized with cholesterol, while the unsaturated one is excluded from the domain area. More complicated model membranes which involve a functional membrane protein glycophorin are also investigated and different membrane properties are observed compared to the systems without glycophorin.

9.
J Am Geriatr Soc ; 49(6): 771-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11454116

RESUMO

OBJECTIVE: To assess the relationships between home death and a set of demographic, disease-related, and health-resource factors among individuals who died of cancer. DESIGN: Prospective cohort study. SETTING: All adult deaths from cancer in Connecticut during 1994. PARTICIPANTS: Six thousand eight hundred and thirteen individuals who met all of the following criteria: died of a cancer-related cause in 1994, had previously been diagnosed with cancer in Connecticut, and were age 18 and older at the time of death. MEASUREMENT: Site of death. RESULTS: Twenty-nine percent of the study sample died at home, 42% died in a hospital, 17% died in a nursing home, and 11% died in an inpatient hospice facility. Multivariate analysis indicated that demographic characteristics (being married, female, white, and residing in a higher income area), disease-related factors (type of cancer, longer survival postdiagnosis), and health-resource factors (greater availability of hospice providers, less availability of hospital beds) were associated with dying at home rather than in a hospital or inpatient hospice. CONCLUSIONS: The implications of this study for clinical practice and health planning are considerable. The findings identify groups (men, unmarried individuals, and those living in lower income areas) at higher risk for institutionalized death-groups that may be targeted for possible interventions to promote home death when home death is preferred by patients and their families. Further, the findings suggest that site of death is influenced by available health-system resources. Thus, if home death is to be supported, the relative availability of hospital beds and hospice providers may be an effective policy tool for promoting home death.


Assuntos
Serviços de Assistência Domiciliar/estatística & dados numéricos , Institucionalização/estatística & dados numéricos , Neoplasias/mortalidade , Assistência Terminal/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Connecticut/epidemiologia , Feminino , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Pesquisa sobre Serviços de Saúde , Humanos , Renda/estatística & dados numéricos , Masculino , Estado Civil/estatística & dados numéricos , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Características de Residência/estatística & dados numéricos , Fatores de Risco , Programa de SEER , Distribuição por Sexo , Análise de Sobrevida , População Branca/estatística & dados numéricos
10.
J Appl Physiol (1985) ; 82(1): 211-8, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9029218

RESUMO

This study tested for the hypothesis that mechanical loading, not stimulation frequency per se, plays a key role in determining the plasticity of myosin heavy chain (MHC) protein isoform expression in muscle undergoing resistance training. Female Sprague-Dawley rats were randomly assigned to resistance-training programs that employed active 1) shortening (n = 7) or 2) lengthening contractions (n = 8). The medial gastrocnemius (MG) muscles in each group trained under loading conditions that approximated 90-95% of maximum isometric tetanic tension but were stimulated at frequencies of 100 and approximately 25 Hz, respectively. Lengthening and shortening contractions were produced by using a Cambridge ergometer system. The MG muscles trained every other day, performing a total of 16 training session. Both training programs produced significant (P < 0.01) and similar reductions in the fast type IIB MHC protein isoform in the white MG muscle, reducing its relative content to approximately 50% of the total MHC protein isoform pool. These changes were accompanied by increases in the relative content of the fast type IIX MHC protein isoform that were of similar magnitude for both groups. The results of this study clearly demonstrate that stimulation frequency does not play a key role in modulating MHC isoform alterations that result from high-resistance training.


Assuntos
Cadeias Pesadas de Miosina/metabolismo , Cadeias Pesadas de Miosina/fisiologia , Animais , Estimulação Elétrica , Eletroforese , Feminino , Ratos , Ratos Sprague-Dawley
11.
J Appl Physiol (1985) ; 85(6): 2237-48, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9843548

RESUMO

Single-fiber (n = 3,818 fibers) electrophoretic analyses were used to delineate the separate and combined effects of hyperthyroidism (T3) and hindlimb suspension (HS) on the myosin heavy chain (MHC) isoform composition (1-, 2-, and 4-wk time points) of the rat soleus muscle. The key findings of this study are as follows. First, T3 and HS both altered the distribution of MHC isoforms at the single-fiber level; however, the populations of fibers produced by these two interventions were clearly different from one another. Second, T3 + HS rapidly converted the soleus into a fast muscle, producing large increases in the relative contents of the fast type IIx and IIb MHC isoforms which were primarily expressed in several populations of hybrid fibers (e.g., types I/IIa/IIx, I/IIx/IIb, I/IIa/IIx/IIb). Finally, T3 + HS produced unique populations of hybrid fibers that did not adhere to the Ileft arrow over right arrow IIaleft arrow over right arrow IIxleft arrow over right arrow IIb sequential scheme of MHC plasticity. Collectively, the findings of this study demonstrate that the intervention of T3 + HS is a powerful model for manipulating and studying MHC isoform plasticity in slow skeletal muscle.


Assuntos
Elevação dos Membros Posteriores/fisiologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Tri-Iodotironina/farmacologia , Animais , Eletroforese , Feminino , Hipertireoidismo/induzido quimicamente , Hipertireoidismo/metabolismo , Fibras Musculares de Contração Rápida/efeitos dos fármacos , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Lenta/efeitos dos fármacos , Fibras Musculares de Contração Lenta/metabolismo , Cadeias Pesadas de Miosina/química , Cadeias Pesadas de Miosina/classificação , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
12.
J Appl Physiol (1985) ; 80(5): 1503-12, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8727533

RESUMO

The overall objective of the studies reported herein was to examine the effects of high-resistance training on myosin heavy-chain (MHC) protein and mRNA isoform expression. The findings from these studies can be summarized as follows: 1) there was a substantial increase in the fast type IIX MHC protein isoform content of the trained red and white medial gastrocnemius muscles, but this did not occur until after the eighth training session (i.e., 16 days); 2) single-fiber analyses demonstrated that many so-called fast type IIB fibers contained small amounts of the fast type IIX MHC protein isoform and that the high-resistance training program altered the bias of fast type IIB-type IIX MHC protein isoform distribution in these fibers but did not increase the number of fibers that could be categorized as exclusively fast type IIX fibers; 3) the high-resistance training program produced a rapid (i.e., after two training sessions) elevation in the fast type IIX MHC mRNA isoform and a corresponding repression of the fast type IIB MHC mRNA isoform; and 4) the dose-response study revealed that as few as 10 contractions (40 s) per training session were capable of elevating the expression of the fast type IIX MHC mRNA isoform by approximately 250%. These collective findings demonstrate that high-resistance training is a powerful modulator of MHC protein isoforms and that pretranslational mechanisms are very sensitive to even small amounts of high-resistance training.


Assuntos
Músculo Esquelético/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Miosinas/metabolismo , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Animais , Estimulação Elétrica , Feminino , Imuno-Histoquímica , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
13.
J Appl Physiol (1985) ; 76(4): 1764-73, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8045858

RESUMO

This study examined changes in contractile, biochemical, and histochemical properties of slow antigravity skeletal muscle after a 6-day spaceflight mission. Twelve male Sprague-Dawley rats were randomly divided into two groups: flight and ground-based control. Approximately 3 h after the landing, in situ contractile measurements were made on the soleus muscles of the flight animals. The control animals were studied 24 h later. The contractile measurements included force-velocity relationship, force-frequency relationship, and fatigability. Biochemical measurements focused on the myosin heavy chain (MHC) and myosin light chain profiles. Adenosine-triphosphatase histochemistry was performed to identify cross-sectional area of slow and fast muscle fibers and to determine the percent fiber type distribution. The force-velocity relationships of the flight muscles were altered such that maximal isometric tension (Po) was decreased by 24% and maximal shortening velocity was increased by 14% (P < 0.05). The force-frequency relationship of the flight muscles was shifted to the right of the control muscles. At the end of the 2-min fatigue test, the flight muscles generated only 34% of Po, whereas the control muscles generated 64% of Po. The flight muscles exhibited de novo expression of the type IIx MHC isoform as well as a slight decrease in the slow type I and fast type IIa MHC isoforms. Histochemical analyses of flight muscles demonstrated a small increase in the percentage of fast type II fibers and a greater atrophy of the slow type I fibers. The results demonstrate that contractile properties of slow antigravity skeletal muscle are sensitive to the microgravity environment and that changes begin to occur within the 1st wk. These changes were at least, in part, associated with changes in the amount and type of contractile protein expressed.


Assuntos
Músculos/metabolismo , Músculos/fisiologia , Miosinas/metabolismo , Voo Espacial , Adenosina Trifosfatases/imunologia , Adenosina Trifosfatases/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Eletroforese em Gel de Poliacrilamida , Fadiga/fisiopatologia , Histocitoquímica , Isomerismo , Contração Isométrica/fisiologia , Cinética , Masculino , Contração Muscular/fisiologia , Subfragmentos de Miosina/imunologia , Subfragmentos de Miosina/metabolismo , Miosinas/imunologia , Miosinas/isolamento & purificação , Ratos , Ratos Sprague-Dawley
14.
J Appl Physiol (1985) ; 81(1): 123-32, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8828654

RESUMO

This study examined the effects of microgravity (14 days) on 1) the contractile properties of the soleus (Sol), an antigravity skeletal muscle; and 2) the myosin heavy chain (MHC) protein and mRNA isoform content of the Sol, vastus intermedius (VI), plantaris (Plan), and tibialis anterior (TA) muscles. The force-velocity relationships of the flight Sol muscles had a significant reduction in maximal isometric tension (-37%) and a corresponding increase in maximal shortening velocity (+20%). Additionally, the force-frequency relationship of the flight Sol muscles was shifted to the right of the ground-based control group. Microgravity had the greatest effect on muscle fiber composition in the Sol muscle, with a reduction in slow muscle fibers and a corresponding increase in muscle fibers categorized as hybrid fibers. The estimated absolute MHC isoform content was altered to the greatest extent in the Sol and VI muscles, with significant decreases and elevations in the slow type I and fast type IIX MHC protein isoforms, respectively. Consistent with the protein data, both the flight Sol and VI muscles exhibited significant elevations in the fast type IIX MHC mRNA isoform. In contrast, however, the flight Plan and TA groups had significant increases in the fast type IIB MHC mRNA isoform content without corresponding changes at the protein level. The results of this study suggest that spaceflight of even short duration produces important changes in the contractile properties of antigravity skeletal muscle. These changes are mediated by alterations in MHC phenotype and reductions in muscle mass. In some instances, the alterations in MHC mRNA isoform content seemed to be uncoupled from those occurring at the protein level. This apparent uncoupling between mRNA and protein expression demonstrates that the effects of microgravity must be better understood at the transcriptional, translational, and post-translational levels.


Assuntos
Proteínas Contráteis/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Miosinas/metabolismo , Ausência de Peso/efeitos adversos , Animais , Peso Corporal/fisiologia , Proteínas Contráteis/isolamento & purificação , Proteínas Contráteis/fisiologia , Eletroforese em Gel de Poliacrilamida , Imuno-Histoquímica , Contração Isométrica/fisiologia , Locomoção/fisiologia , Masculino , Músculo Esquelético/enzimologia , Miofibrilas/fisiologia , Cadeias Pesadas de Miosina/biossíntese , Cadeias Pesadas de Miosina/química , Cadeias Pesadas de Miosina/metabolismo , Miosinas/isolamento & purificação , Miosinas/fisiologia , Tamanho do Órgão/fisiologia , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley
15.
Pharmacol Biochem Behav ; 17(3): 389-92, 1982 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6890681

RESUMO

Repeated blockade of the endorphin receptors eventually induces symptoms resembling an opiate abstinence syndrome, despite the complete absence of opiate narcotics. Rats were injected with 0.6 mg/kg naloxone or with injection vehicle alone twice a day for six days. They were observed twice a day for four subsequent days. Body shakes, head shakes, scratches and total symptoms were significantly elevated in the naloxone treated group over controls. Symptoms were completely reversed by a small dose of morphine but not by naloxone. In a second experiment, rats were injected for ten days with the same dosage of naloxone. The abstinence-like syndrome began after six days of naloxone and continued for several days after cessation of injections. Total symptoms, body shakes, scratches and aggression were significantly elevated over controls and were reversed by morphine but not by naloxone.


Assuntos
Comportamento Animal/efeitos dos fármacos , Naloxona/farmacologia , Animais , Humanos , Injeções Intravenosas , Masculino , Morfina/farmacologia , Dependência de Morfina/psicologia , Ratos , Ratos Endogâmicos , Síndrome de Abstinência a Substâncias/psicologia
16.
Arch Otolaryngol Head Neck Surg ; 126(7): 874-80, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10889000

RESUMO

BACKGROUND: Studies have shown that canine laryngeal muscle contains a large number of muscle fibers that coexpress varying combinations of myosin heavy-chain (MyHC) isoforms. Currently, it is not clear whether this phenomenon is unique to canine laryngeal muscle or occurs in all mammals. OBJECTIVES: To examine the single-fiber MyHC isoform composition of rodent laryngeal muscle and to examine the plasticity of single-fiber MyHC isoform composition via manipulation of thyroid state. RESULTS: (1) Findings of single-fiber electrophoretic analyses clearly demonstrate that most fibers in both the posterior cricoarytenoid and thyroarytenoid muscles exhibit MyHC polymorphism. However, the proportions and patterns of polymorphism appear to be muscle specific. (2) Although the fast type IIL isoform was observed in fibers from both muscles, it was always coexpressed in combination with other MyHC isoforms (ie, no pure type IIL fibers were found), and always represented a minor proportion of the total MyHC pool. (3) Altering the thyroid state proved a useful tool for exploring the scope of MyHC isoform expression in these muscles. While the posterior cricoarytenoid muscle seemed more sensitive to the thyroid state, transitions in both muscles were primarily confined to the fast type IIX and IIB MyHC isoforms. CONCLUSION: The findings of this study support the concept that single-fiber MyHC polymorphism occurs commonly in mammalian laryngeal muscle.


Assuntos
Músculos Laríngeos/química , Músculos Laríngeos/citologia , Cadeias Pesadas de Miosina/análise , Hormônios Tireóideos/fisiologia , Animais , Eletroforese , Feminino , Polimorfismo Genético , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie , Tri-Iodotironina/fisiologia
17.
Otolaryngol Head Neck Surg ; 118(1): 86-94, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9450834

RESUMO

This report describes the first known investigation of canine laryngeal muscle in which single fibers were dissected and their myosin heavy chain (MHC) isoform content was analyzed. Both SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and western blot techniques were used. The data from single fiber SDS-PAGE indicate that the lateral cricoarytenoid (LCA) is predominantly a fast muscle composed of the following MHC isoforms: Type I, 16.3%; Type IIA, 71.3%; Type IIX, 10.4%; and Type IIB, 2.0%. The results reveal a phenomenon that, to our knowledge, has not been previously described for laryngeal muscle: the presence of two or more MHC isoforms in a single canine LCA muscle fiber. A large number (41%) of muscle fibers coexpressed two or more MHC isoforms. The three most common patterns of coexpression were Type IIA/IIX (72%), Type IIA/I (16%), and Type IIA/IIX/I (8%). Interestingly, the fast Type IIX MHC isoform was typically present with other isoforms and rarely found by itself in individual fibers. Additional experiments are underway to determine whether other laryngeal muscles exhibit such an unusually high ratio of MHC isoform polymorphism.


Assuntos
Músculos Laríngeos/química , Cadeias Pesadas de Miosina/análise , Animais , Cartilagem Aritenoide , Western Blotting , Cartilagem Cricoide , Cães , Eletroforese em Gel de Poliacrilamida , Cadeias Pesadas de Miosina/química
18.
J Anim Sci ; 59(1): 237-45, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6086564

RESUMO

Four rumen fistulated wether and beef steers were used to evaluate differences in dry matter digestibility (DMD) between cattle and sheep. They were fed either perennial ryegrass or switchgrass hay at an ad libitum or restricted level for four experimental periods. Significant ruminant species X forage and ruminant species X level of intake (P less than .05) interactions were observed for digestible dry matter. The steers digested the switchgrass 7 percentage units greater than the wethers while ryegrass was digested equally. Digestibility differences between the steers and wethers were 6 percentage units at the ad libitum level of intake and 1 unit at the restricted level of intake. Crude protein digestibility tended to be greater (P less than .10) for sheep with a 7 unit difference for switchgrass and a 3 unit difference for ryegrass. The mean ruminal solids retention time of the digesta was approximately (P less than .01) 50% greater (26.0 vs 17.4 h) in cattle, with no difference in ruminal liquid dilution rate (LD) between animal species. Total ruminal volatile fatty acid concentration differed (P less than .01) with level of intake; however, no influence due to intake on the molar proportion of acetate (P greater than .10) or propionate (P greater than .10) was evident in spite of a difference (P less than .01) in LD. Rumen pH (P less than .05) and osmolality (P less than .01) were affected by both level of intake and forage, with the ryegrass and high level of intake decreasing pH and increasing osmolality.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ração Animal , Bovinos/metabolismo , Poaceae , Rúmen/metabolismo , Ovinos/metabolismo , Ração Animal/análise , Animais , Fibras na Dieta/análise , Proteínas Alimentares/análise , Digestão , Ácidos Graxos Voláteis/biossíntese , Fermentação , Masculino , Poaceae/análise , Especificidade da Espécie
19.
J Anim Sci ; 79(8): 1983-95, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11518207

RESUMO

A published model designed to predict individual feed required for the observed shrunk BW and ADG of growing cattle when fed in groups was modified and evaluated to improve its accuracy. This model is needed to accurately bill feed and compute cost of gain in marketing programs based on individual animal management. Because of its importance in predicting energy required for growth, a database of 401 steers was used to develop an equation to predict percentage of empty-body fat (EBF) from carcass measurements (12th rib fat thickness, hot carcass weight, USDA quality grade, and longissimus muscle area), which accounted for 61% of the variation in EBF with no bias (P > 0.1). When tested with an independent data set of 951 steers, the equation accounted for 51% of the variation with 1% proportional bias. The large variation in the carcass measurements at a particular EBF observed in this study indicates further improvement is limited by the inability of carcass measurements to account for variation in fat distribution in the various carcass components. Because of its importance in setting the target end point, a database of 1,355 steers and heifers was used to determine the relationship between EBF and USDA quality grade. These data indicate growing and finishing cattle reach Select and low-Choice quality grades at an EBF of 26.15 +/- 0.19 and 28.61 +/- 0.20%, respectively (P < 0.05). A data set of 228 steers from different breeds from two serial slaughter studies indicated 14.26 +/- 1.52 kg of empty BW change are required to increase EBF one percentage unit for cattle fed high-energy diets; this adjustment is needed to adjust final shrunk BW to the target EBF end point. The model to predict DM required with modifications developed in this study was evaluated with data from 365 individually fed cattle and it accounted for 74% of the variation in observed DM consumed with no bias (P > 0.1). When the revised model was applied to a commercial feedlot data set containing 12,105 steers and heifers, the total observed DM consumed was predicted with a bias of less than 1%. The model presented in this study accounts for differences known to affect animal requirements (breed type, BW and ADG, and weight at the target EBF end point) and can be used to fairly allocate feed to individuals fed in a group under commercial feedlot conditions.


Assuntos
Ração Animal , Criação de Animais Domésticos/tendências , Fenômenos Fisiológicos da Nutrição Animal , Bovinos/fisiologia , Animais , Composição Corporal , Peso Corporal , Bases de Dados Factuais , Feminino , Previsões , Masculino , Carne/normas , Modelos Biológicos
20.
Br J Nurs ; 4(18): 1094-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8535116

RESUMO

The delivery of nursing care should be based on meeting patients' individual needs. This article presents the findings of a small-scale study which explored the feelings that people express regarding the care they would like and receive from nurses.


Assuntos
Cuidados de Enfermagem/psicologia , Satisfação do Paciente , Adulto , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Cuidados de Enfermagem/métodos , Inquéritos e Questionários
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