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1.
Health Promot Int ; 39(3)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949405

RESUMEN

Health literacy is an increasingly required need to help individuals, families and communities manage their health and health conditions. It is linked with better self-adherence to treatments, use of resources, access to care and overall reduced costs in healthcare. In the Gulf Cooperation Council (GCC), which comprises Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates, various health literacy programs are implemented across states to address people's unique and complex healthcare needs. This article aims to examine the current literature and assess the factors that influence the outcomes of health literacy programs within the GCC. An integrative review methodology has been conducted to pursue a comprehensive understanding of health literacy interventions in the GCC. This investigative approach was shaped by Whittemore and Knafl's framework (2005), which includes problem identification, literature search, data evaluation, data analysis and presentation. The literature on the effectiveness of health literacy interventions and the factors that shape them are notably limited worldwide and within the GCC region. This integrative review addresses this knowledge gap and highlights the significance of key themes such as sessions, evaluation and improvement in shaping health literacy outcomes within the GCC region. Through this integrative review, the three main themes of sessions, evaluation and improvement were identified as influencing the outcomes of health literacy programs within the GCC.


Asunto(s)
Alfabetización en Salud , Humanos , Medio Oriente , Promoción de la Salud/métodos , Evaluación de Programas y Proyectos de Salud
2.
J Dairy Sci ; 106(12): 8357-8367, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37641250

RESUMEN

Several studies have been focused on the effect of milk protein genetic variants on milk physicochemical properties and functionality in recent years. ß-casein, an important protein related to milk processibility, has been reported to have 2 main genetic variants A1 and A2, for which cows may be homozygous or heterozygous. In this study, several physicochemical properties of milk with ß-casein variants A1A1, A1A2, and A2A2 from 3 collection occasions were analyzed. Higher manganese content and lower pH were found to be associated with the A1A1 variant compared with the other 2 genotypes. Better rennet and acid coagulation were found in A1A1 milk compared with A1A2 and A2A2 milk (although P > 0.05), whereas A2A2 milk was more stable to creaming compared with the other 2 genotypes, which may be linked to its smaller fat globule size. Thus, milk from cows with A1A1 genotype could be preferable for cheese making, while that with A2A2 variant can be used in formulations requiring good stability against creaming, and for example, yogurt making, where the softer yogurt texture may be easier to digest.


Asunto(s)
Caseínas , Leche , Femenino , Bovinos , Animales , Caseínas/química , Leche/química , Proteínas de la Leche/análisis , Genotipo , Heterocigoto
3.
Mol Psychiatry ; 18(6): 721-8, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22889924

RESUMEN

Tourette's syndrome (TS) is a developmental disorder that has one of the highest familial recurrence rates among neuropsychiatric diseases with complex inheritance. However, the identification of definitive TS susceptibility genes remains elusive. Here, we report the first genome-wide association study (GWAS) of TS in 1285 cases and 4964 ancestry-matched controls of European ancestry, including two European-derived population isolates, Ashkenazi Jews from North America and Israel and French Canadians from Quebec, Canada. In a primary meta-analysis of GWAS data from these European ancestry samples, no markers achieved a genome-wide threshold of significance (P<5 × 10(-8)); the top signal was found in rs7868992 on chromosome 9q32 within COL27A1 (P=1.85 × 10(-6)). A secondary analysis including an additional 211 cases and 285 controls from two closely related Latin American population isolates from the Central Valley of Costa Rica and Antioquia, Colombia also identified rs7868992 as the top signal (P=3.6 × 10(-7) for the combined sample of 1496 cases and 5249 controls following imputation with 1000 Genomes data). This study lays the groundwork for the eventual identification of common TS susceptibility variants in larger cohorts and helps to provide a more complete understanding of the full genetic architecture of this disorder.


Asunto(s)
Colágenos Fibrilares/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple/genética , Síndrome de Tourette/genética , Adolescente , Adulto , Trastorno por Déficit de Atención con Hiperactividad/etiología , Trastorno por Déficit de Atención con Hiperactividad/genética , Estudios de Casos y Controles , Cromosomas Humanos Par 9/genética , Femenino , Genotipo , Humanos , Cooperación Internacional , Masculino , Metaanálisis como Asunto , Trastorno Obsesivo Compulsivo/etiología , Trastorno Obsesivo Compulsivo/genética , Síndrome de Tourette/complicaciones , Población Blanca/genética , Adulto Joven
4.
Spinal Cord ; 52(12): 911-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25330938

RESUMEN

STUDY DESIGN: A descriptive audit. OBJECTIVES: To audit the participation and satisfaction in a Massive Open Online Course (MOOC) for teaching physiotherapy students and physiotherapists about spinal cord injuries. SETTING: Global and online. METHODS: A 5-week MOOC about the physiotherapy management of spinal cord injuries was hosted by Physiopedia and run in partnership with the International Spinal Cord Society. The MOOC was based on the physiotherapy-specific module of www.elearnSCI.org, and also involved extra readings, activities and online discussion through a closed Facebook group. Participation and satisfaction was quantified through a pre- and post-MOOC knowledge assessment and an online course evaluation. Participation was also gauged through Facebook activity and internet-based usage statistics. RESULTS: Three thousand five hundred and twenty-three people from 108 countries registered for the MOOC and 2527 joined the Facebook group. One thousand one hundred and twenty-one completed the pre- and post-MOOC knowledge assessments, with more completing one or the other. The median (interquartile range) results for those who completed the pre and post-MOOC knowledge assessments were 70% (60-80%) and 90% (80-95%), respectively. One thousand and twenty-nine completed the online course evaluation, with more than 80% agreeing or strongly agreeing with 12 of the 13 positive statements posed to them about the course. CONCLUSION: Most participants who completed the MOOC performed well on the post-MOOC knowledge assessment and enjoyed the learning experience. However, these results may be biased if those who did not complete the MOOC were dissatisfied and/or did not sit the post-MOOC knowledge assessment.


Asunto(s)
Fisioterapeutas/educación , Especialidad de Fisioterapia/educación , Traumatismos de la Médula Espinal/terapia , Curriculum , Evaluación Educacional , Humanos , Cooperación Internacional , Internet , Auditoría Administrativa , Sistemas en Línea , Satisfacción Personal , Medios de Comunicación Sociales , Estudiantes
5.
Proc Natl Acad Sci U S A ; 107(19): 8818-23, 2010 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-20421470

RESUMEN

Ammonia-oxidizing archaea are ubiquitous in marine and terrestrial environments and now thought to be significant contributors to carbon and nitrogen cycling. The isolation of Candidatus "Nitrosopumilus maritimus" strain SCM1 provided the opportunity for linking its chemolithotrophic physiology with a genomic inventory of the globally distributed archaea. Here we report the 1,645,259-bp closed genome of strain SCM1, revealing highly copper-dependent systems for ammonia oxidation and electron transport that are distinctly different from known ammonia-oxidizing bacteria. Consistent with in situ isotopic studies of marine archaea, the genome sequence indicates N. maritimus grows autotrophically using a variant of the 3-hydroxypropionate/4-hydroxybutryrate pathway for carbon assimilation, while maintaining limited capacity for assimilation of organic carbon. This unique instance of archaeal biosynthesis of the osmoprotectant ectoine and an unprecedented enrichment of multicopper oxidases, thioredoxin-like proteins, and transcriptional regulators points to an organism responsive to environmental cues and adapted to handling reactive copper and nitrogen species that likely derive from its distinctive biochemistry. The conservation of N. maritimus gene content and organization within marine metagenomes indicates that the unique physiology of these specialized oligophiles may play a significant role in the biogeochemical cycles of carbon and nitrogen.


Asunto(s)
Procesos Autotróficos/genética , Crenarchaeota/genética , Genoma Arqueal/genética , Internacionalidad , Nitrógeno/metabolismo , Agua de Mar/microbiología , Aminoácidos Diaminos/biosíntesis , Amoníaco/metabolismo , División Celular/genética , Crenarchaeota/citología , Transporte de Electrón/genética , Metabolismo Energético/genética , Evolución Molecular , Regulación de la Expresión Génica , Metagenoma/genética , Oxidación-Reducción , Fotosíntesis/genética , Filogenia , ARN no Traducido/genética , Análisis de Secuencia de ADN , Transcripción Genética
6.
J Exp Med ; 192(5): 637-46, 2000 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-10974030

RESUMEN

The impact of HIV-associated immunopathogenesis on B cells has been largely associated with indirect consequences of viral replication. This study demonstrates that HIV interacts directly with B cells in both lymphoid tissues and peripheral blood. B cells isolated from lymph node and peripheral blood mononuclear cells (PBMCs) of 4 and 23 chronically infected patients, respectively, demonstrated similar capacities to pass virus to activated HIV-negative PBMCs when compared with CD4(+) cells from the same patients. However, in contrast to T cells, virus associated with B cells was surface bound, as shown by its sensitivity to pronase and the staining pattern revealed by in situ amplification of HIV-1 RNA. Cell sorting and ligand displacing approaches established that CD21 was the HIV-binding receptor on B cells, and that this association was mediated through complement-opsonized virus. These B cells were also found to express significantly lower levels of CD21 compared with HIV-negative individuals, suggesting a direct perturbing effect of HIV on B cells. These findings suggest that B cells, although they themselves are not readily infected by HIV, are similar to follicular dendritic cells in their capacity to serve as extracellular reservoirs for HIV-1. Furthermore, B cells possess the added capability of circulating in peripheral blood and migrating through tissues where they can potentially interact with and pass virus to T cells.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Linfocitos B/virología , Complemento C3/fisiología , VIH-1/fisiología , Activación de Linfocitos , Receptores de Complemento 3d/fisiología , Linfocitos T/virología , Virión/fisiología , Síndrome de Inmunodeficiencia Adquirida/virología , Anticuerpos Monoclonales/inmunología , Enfermedad Crónica , Humanos , ARN Viral/análisis
7.
J Sports Med Phys Fitness ; 50(1): 85-92, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20308978

RESUMEN

AIM: To validate the testosterone (T) and cortisol (C) concentration measures in saliva in response to short high-intensity exercise. METHODS: Nine healthy males provided matching saliva and plasma samples before and after a 30-second Wingate cycle test. Saliva was assayed for T (Sal-T) and C (Sal-C) concentrations, and plasma for total T and total C, sex hormone-binding globulin, corticosteroid-binding globulin (CBG) and albumin concentrations. The plasma free and bioavailable hormones were calculated. RESULTS: The Sal-T and plasma T correlations were weak to moderate (r=0.57-0.61) when examined between individuals (pooled data for all participants), but these relationships improved (r = 0.71-0.73) within individuals (data for each participant on average). The Sal-C and plasma C correlations were strong both between individuals (r=0.81-0.84) and within individuals (r=0.83-0.84). The peak relative increases in Sal-T (35+/-9%) and Sal-C (63+/-29%) concentrations exceeded the plasma total and/or free hormones, but not the bioavailable hormones. Albumin (10+/-3%) and CBG (16+/-4%) also increased with exercise, along with blood lactate (943+/-119%). CONCLUSION: The Sal-T and Sal-C concentration measures were validated in response to short high-intensity exercise, especially for individuals. The hormonal changes in saliva were also more sensitive to exercise (i.e. greater relative responses) than the plasma total and/or free hormones, potentially arising from changes in the binding proteins and blood lactate. These findings support the use of saliva as a medium for steroid determination in sport.


Asunto(s)
Adaptación Fisiológica , Umbral Anaerobio/fisiología , Ejercicio Físico/fisiología , Hidrocortisona/análisis , Saliva/química , Testosterona/análisis , Glándulas Suprarrenales , Adulto , Albúminas/análisis , Análisis de Varianza , Composición Corporal , Humanos , Hidrocortisona/sangre , Hidrocortisona/química , Masculino , Globulina de Unión a Hormona Sexual/análisis , Estadística como Asunto , Testosterona/sangre , Transcortina/análisis
8.
Int J Oral Maxillofac Surg ; 49(2): 192-199, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31301925

RESUMEN

Benign parotid tumours usually present as a slow-growing, asymptomatic mass in the pre-auricular region. Although they are uncommon, surgical excision is the mainstay of treatment due to the risk of malignant transformation in some benign tumours. Surgical techniques have evolved over the years, with superficial parotidectomy and extracapsular dissection being the current procedures of choice. There is currently no gold standard, and it remains unclear which surgical modality is the superior option. A literature review was performed in relation to the relative merits of each technique and to evaluate the reasons underpinning the ongoing debate. A total of 16 papers comparing the main clinical outcomes of the procedures were critically reviewed using the PRISMA protocol. Overall, extracapsular dissection indicated a reduced recurrence rate, facial nerve paralysis, Frey syndrome, and operation time. The superior outcomes following extracapsular dissection could be attributed to the less radical nature of the procedure. However, there were various limitations identified within the review that may have affected the results. Selection bias was the most significant, with patients assigned to the different procedures depending on the tumour size and location. Consequently, the debate continues as to what constitutes the gold standard of care for benign parotid tumours.


Asunto(s)
Neoplasias de la Parótida , Sudoración Gustativa , Humanos , Recurrencia Local de Neoplasia , Glándula Parótida , Complicaciones Posoperatorias , Estudios Retrospectivos
9.
Sci Rep ; 10(1): 8142, 2020 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-32424316

RESUMEN

Mass transport by aqueous fluids is a dynamic process in shallow crustal systems, redistributing nutrients as well as contaminants. Rock matrix diffusion into fractures (void space) within crystalline rock has been postulated to play an important role in the transient storage of solutes. The reacted volume of host rock involved, however, will be controlled by fluid-rock reactions. Here we present the results of a study which focusses on defining the length scale over which rock matrix diffusion operates within crystalline rock over timescales that are relevant to safety assessment of radioactive and other long-lived wastes. Through detailed chemical and structural analysis of natural specimens sampled at depth from an active system (Toki Granite, Japan), we show that, contrary to commonly proposed models, the length scale of rock matrix diffusion may be extremely small, on the order of centimetres, even over timescales of millions of years. This implies that in many cases the importance of rock matrix diffusion will be minimal. Additional analyses of a contrasting crystalline rock system (Carnmenellis Granite, UK) corroborate these results.

10.
Science ; 283(5405): 1168-71, 1999 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-10024243

RESUMEN

Small nucleolar RNAs (snoRNAs) are required for ribose 2'-O-methylation of eukaryotic ribosomal RNA. Many of the genes for this snoRNA family have remained unidentified in Saccharomyces cerevisiae, despite the availability of a complete genome sequence. Probabilistic modeling methods akin to those used in speech recognition and computational linguistics were used to computationally screen the yeast genome and identify 22 methylation guide snoRNAs, snR50 to snR71. Gene disruptions and other experimental characterization confirmed their methylation guide function. In total, 51 of the 55 ribose methylated sites in yeast ribosomal RNA were assigned to 41 different guide snoRNAs.


Asunto(s)
Algoritmos , Modelos Genéticos , Modelos Estadísticos , ARN de Hongos/análisis , ARN Ribosómico/metabolismo , ARN Nuclear Pequeño/análisis , Saccharomyces cerevisiae/genética , Emparejamiento Base , Nucléolo Celular/metabolismo , Metilación , ARN de Hongos/química , ARN de Hongos/genética , ARN de Hongos/metabolismo , ARN Ribosómico/química , ARN Ribosómico/genética , ARN Nuclear Pequeño/química , ARN Nuclear Pequeño/genética , Ribosa/metabolismo , Programas Informáticos
11.
Science ; 288(5465): 517-22, 2000 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-10775111

RESUMEN

In eukaryotes, dozens of posttranscriptional modifications are directed to specific nucleotides in ribosomal RNAs (rRNAs) by small nucleolar RNAs (snoRNAs). We identified homologs of snoRNA genes in both branches of the Archaea. Eighteen small sno-like RNAs (sRNAs) were cloned from the archaeon Sulfolobus acidocaldarius by coimmunoprecipitation with archaeal fibrillarin and NOP56, the homologs of eukaryotic snoRNA-associated proteins. We trained a probabilistic model on these sRNAs to search for more sRNAs in archaeal genomic sequences. Over 200 additional sRNAs were identified in seven archaeal genomes representing both the Crenarchaeota and the Euryarchaeota. snoRNA-based rRNA processing was therefore probably present in the last common ancestor of Archaea and Eukarya, predating the evolution of a morphologically distinct nucleolus.


Asunto(s)
Archaea/genética , ARN de Archaea/genética , ARN Nucleolar Pequeño/genética , Sulfolobus acidocaldarius/genética , Proteínas Arqueales/genética , Secuencia de Bases , Proteínas Cromosómicas no Histona/genética , Clonación Molecular , Genoma Arqueal , Metilación , Modelos Estadísticos , Datos de Secuencia Molecular , Proteínas Nucleares/genética , Procesamiento Postranscripcional del ARN , ARN de Archaea/química , ARN de Archaea/metabolismo , ARN Ribosómico/química , ARN Ribosómico/genética , ARN Ribosómico/metabolismo , ARN Nucleolar Pequeño/química , ARN Nucleolar Pequeño/metabolismo , ARN Pequeño no Traducido
13.
Mol Cell Biol ; 21(20): 6870-81, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11564871

RESUMEN

In addition to directing transcription initiation, core promoters integrate input from distal regulatory elements. Except for rare exceptions, it has been generally found that eukaryotic tRNA and rRNA genes do not contain TATA promoter elements and instead use protein-protein interactions to bring the TATA-binding protein (TBP), to the core promoter. Genomewide analysis revealed TATA elements in the core promoters of tRNA and 5S rRNA (Pol III), U1 to U5 snRNA (Pol II), and 37S rRNA (Pol I) genes in Schizosaccharomyces pombe. Using tRNA-dependent suppression and other in vivo assays, as well as in vitro transcription, we demonstrated an obligatory requirement for upstream TATA elements for tRNA and 5S rRNA expression in S. pombe. The Pol III initiation factor Brf is found in complexes with TFIIIC and Pol III in S. pombe, while TBP is not, consistent with independent recruitment of TBP by TATA. Template commitment assays are consistent with this and confirm that the mechanisms of transcription complex assembly and initiation by Pol III in S. pombe differ substantially from those in other model organisms. The results were extended to large-rRNA synthesis, as mutation of the TATA element in the Pol I promoter also abolishes rRNA expression in fission yeast. A survey of other organisms' genomes reveals that a substantial number of eukaryotes may use widespread TATAs for transcription. These results indicate the presence of TATA-unified transcription systems in contemporary eukaryotes and provide insight into the residual need for TBP by all three Pols in other eukaryotes despite a lack of TATA elements in their promoters.


Asunto(s)
Proteínas de Unión al ADN/genética , Regiones Promotoras Genéticas , ARN Polimerasa III/genética , ARN Polimerasa II/genética , ARN Polimerasa I/genética , Schizosaccharomyces/metabolismo , Factores de Transcripción/genética , Transcripción Genética , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Secuencia de Bases , Secuencia Conservada , Proteínas de Unión al ADN/metabolismo , Evolución Molecular , Genoma Fúngico , Immunoblotting , Datos de Secuencia Molecular , ARN Polimerasa I/metabolismo , ARN Polimerasa II/metabolismo , ARN Polimerasa III/metabolismo , ARN Ribosómico/metabolismo , ARN Ribosómico 5S/genética , ARN de Transferencia/metabolismo , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Proteína de Unión a TATA-Box , Factores de Transcripción/metabolismo
14.
J Psychiatr Ment Health Nurs ; 14(7): 688-95, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17880663

RESUMEN

It is widely acknowledged that there are major concerns about quality of care, ward atmosphere, the nature of nurse-patient interactions and patient outcomes in UK psychiatric acute admission units. Brief solution-focused therapy (SFT) is an approach which aims to shift the focus of interactions in professional care away from the traditional concentration on an individual's problems and weaknesses towards a more proactive identification of their strengths and positive coping mechanisms. This approach relies on a collaborative engagement with patients, in which the nurse or therapist using simple language aims to help the patient construct a plan to ensure their immediate safety while working to identify, focus on and reinforce their strengths and coping mechanisms in the achievement of identified future goals. This paper reports on a pilot study whose principal objective was to determine whether a short training in brief SFT for psychiatric nurses can produce measurable improvements in nurse-patient interactions in two psychiatric acute admission wards. In this study, 36 nurses undertook a 2-day training course in SFT and were followed up 3 months after training. Positive results were obtained on a number of measures indicating that nurses had acquired knowledge and skills and were applying SFT techniques in their clinical work.


Asunto(s)
Actitud del Personal de Salud , Trastornos Mentales/terapia , Enfermeras y Enfermeros , Admisión del Paciente , Enfermería Psiquiátrica/educación , Psicoterapia Breve , Enseñanza , Adulto , Femenino , Hospitalización , Humanos , Masculino , Trastornos Mentales/rehabilitación , Proyectos Piloto , Reino Unido
17.
Mater Sci Eng C Mater Biol Appl ; 71: 483-497, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-27987735

RESUMEN

Surface modification is an important step in production of medical implants. Surface roughening creates additional surface area to enhance the bonding between the implant and the bone. Recent research provided a means to alter the microstructure of titanium by severe plastic deformation (SPD) in order to increase its strength, and thereby reduce the size of the implants (specifically, their diameter). The purpose of the present study was to examine the effect of bulk microstructure of commercially pure titanium with coarse-grained (CG) and ultrafine-grained (UFG) bulk structure on the surface state of these materials after surface modification by sand blasting and acid etching (SLA). It was shown that SLA-modified surface characteristics, in particular, roughness, chemistry, and wettability, were affected by prior SPD processing. Additionally, biocompatibility of UFG titanium was examined using osteosarcoma cell line SaOS-2 and primary human adipose-derived mesenchymal stem cell (adMSC) cultures. Enhanced cell viability as well as increased matrix mineralization during osteogenic differentiation of MSCs on the surface of ultrafine-grained titanium was shown.


Asunto(s)
Diferenciación Celular , Células Madre Mesenquimatosas/metabolismo , Osteoblastos/metabolismo , Osteogénesis , Titanio/química , Línea Celular , Humanos , Células Madre Mesenquimatosas/citología , Osteoblastos/citología , Propiedades de Superficie
18.
Meat Sci ; 73(2): 304-12, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22062302

RESUMEN

The effect of electrical stimulation of lamb carcasses (n=269) or its absence (n=257) on shear force of m. longissimus thoracis et lumborum (LT) was monitored during ageing in pasture-fed merino lambs (n=526). The lambs were slaughtered on four different days allowing durations of between one to 10 days of recovery from pre-slaughter handling (yarding, weighing and crutching) that affected ultimate pH (pH(u)). The right LT was removed 20-40min post-slaughter, tightly-wrapped in cling film (prevents the muscle cross-section increasing and thus minimising shortening) and rapidly cooled to 15°C to enter rigor mortis and age. At 0, 4, 24 and 72h post-slaughter, pH measurements and samples for shear force measurement were taken. Pre-slaughter handling had a significant negative effect on pH(u) and several days recovery were required for pH(u) to reach values associated with optimal meat quality as reflected by pH(u). Lambs with one and three days recovery (no significant difference between them) had a pH(u)>5.7 in 50% of the muscles and 19.4%>pH(u) 5.8. Whereas, in lambs with 8-10 days recovery (no significant difference between them), only 8% had a pH(u)>5.7 and 3.1%>pH(u) 5.8. Within each slaughter day electrically stimulated lambs were always more tender than non-stimulated lambs. For non-stimulated muscles at 72h, shear force values >40N occurred for 11.2% of the muscles: for electrically stimulated muscles at 72h, shear force values >40N occurred for 1.9% of the muscles. The rates of tenderisation were slower for intermediate pH(u) values resulting in higher shear force values at all ageing durations. With ageing at 72h for intermediate pH(u), non-stimulated muscles (n=38) 17.64% were >40N and for stimulated muscles (n=34), 7.9% were >40N.

19.
J Mech Behav Biomed Mater ; 57: 55-68, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26703365

RESUMEN

Surface modification techniques are widely used to enhance the biological response to the implant materials. These techniques generally create a roughened surface, effectively increasing the surface area thus promoting cell adhesion. However, a negative side effect is a higher susceptibility of a roughened surface to failure due to the presence of multiple stress concentrators. The purpose of the study reported here was to examine the effects of surface modification by sand blasting and acid-etching (SLA) on the microstructure and fatigue performance of coarse-grained and ultrafine-grained (UFG) commercially pure titanium. Finer grain sizes, produced by equal channel angular pressing, resulted in lower values of surface roughness in SLA-processed material. This effect was associated with greater resistance of the UFG structure to plastic deformation. The fatigue properties of UFG Ti were found to be superior to those of coarse-grained Ti and conventional Ti-6Al-4V, both before and after SLA-treatment.


Asunto(s)
Ensayo de Materiales , Estrés Mecánico , Titanio/química , Concentración de Iones de Hidrógeno , Propiedades de Superficie
20.
Endocr Relat Cancer ; 12(3): 631-43, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16172196

RESUMEN

Prostate-specific antigen (PSA) and the related kallikrein family of serine proteases are current or emerging biomarkers for prostate cancer detection and progression. Kallikrein 4 (KLK4/hK4) is of particular interest, as KLK4 mRNA has been shown to be elevated in prostate cancer. In this study, we now show that the comparative expression of hK4 protein in prostate cancer tissues, compared with benign glands, is greater than that of PSA and kallikrein 2 (KLK2/hK2), suggesting that hK4 may play an important functional role in prostate cancer progression in addition to its biomarker potential. To examine the roles that hK4, as well as PSA and hK2, play in processes associated with progression, these kallikreins were separately transfected into the PC-3 prostate cancer cell line, and the consequence of their stable transfection was investigated. PC-3 cells expressing hK4 had a decreased growth rate, but no changes in cell proliferation were observed in the cells expressing PSA or hK2. hK4 and PSA, but not hK2, induced a 2.4-fold and 1.7-fold respective increase, in cellular migration, but not invasion, through Matrigel, a synthetic extracellular matrix. We hypothesised that this increase in motility displayed by the hK4 and PSA-expressing PC-3 cells may be related to the observed change in structure in these cells from a typical rounded epithelial-like cell to a spindle-shaped, more mesenchymal-like cell, with compromised adhesion to the culture surface. Thus, the expression of E-cadherin and vimentin, both associated with an epithelial-mesenchymal transition (EMT), was investigated. E-cadherin protein was lost and mRNA levels were significantly decreased in PC-3 cells expressing hK4 and PSA (10-fold and 7-fold respectively), suggesting transcriptional repression of E-cadherin, while the expression of vimentin was increased in these cells. The loss of E-cadherin and associated increase in vimentin are indicative of EMT and provides compelling evidence that hK4, in particular, and PSA have a functional role in the progression of prostate cancer through their promotion of tumour cell migration.


Asunto(s)
Cadherinas/metabolismo , Calicreínas/metabolismo , Antígeno Prostático Específico/metabolismo , Neoplasias de la Próstata/patología , División Celular , Línea Celular Tumoral , Movimiento Celular , Células Epiteliales/patología , Humanos , Calicreínas/genética , Masculino , Mesodermo/patología , Invasividad Neoplásica
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