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1.
Nature ; 593(7860): 548-552, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33882562

RESUMO

Global peatlands store more carbon than is naturally present in the atmosphere1,2. However, many peatlands are under pressure from drainage-based agriculture, plantation development and fire, with the equivalent of around 3 per cent of all anthropogenic greenhouse gases emitted from drained peatland3-5. Efforts to curb such emissions are intensifying through the conservation of undrained peatlands and re-wetting of drained systems6. Here we report eddy covariance data for carbon dioxide from 16 locations and static chamber measurements for methane from 41 locations in the UK and Ireland. We combine these with published data from sites across all major peatland biomes. We find that the mean annual effective water table depth (WTDe; that is, the average depth of the aerated peat layer) overrides all other ecosystem- and management-related controls on greenhouse gas fluxes. We estimate that every 10 centimetres of reduction in WTDe could reduce the net warming impact of CO2 and CH4 emissions (100-year global warming potentials) by the equivalent of at least 3 tonnes of CO2 per hectare per year, until WTDe is less than 30 centimetres. Raising water levels further would continue to have a net cooling effect until WTDe is within 10 centimetres of the surface. Our results suggest that greenhouse gas emissions from peatlands drained for agriculture could be greatly reduced without necessarily halting their productive use. Halving WTDe in all drained agricultural peatlands, for example, could reduce emissions by the equivalent of over 1 per cent of global anthropogenic emissions.

2.
Caries Res ; : 1-10, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657570

RESUMO

INTRODUCTION: Stress can impact mental and physical health, especially during adolescence and young adulthood, but the extent of its contribution to dental caries is poorly understood. The present study assessed the association between perceived stress, cortisol levels (in hair and saliva), and overall caries experience of adolescents and young adults aged 15-25 years. METHODS: Hair and saliva samples were obtained from 93 participants free of periodontal disease. Cortisol in hair and saliva was determined using a competitive enzyme-linked immunosorbent assay. Participants completed a perceived stress questionnaire and underwent full-mouth oral examination by a calibrated examiner. Dental caries experience was based on the decayed, missing, and filled teeth (DMFT) index. Sociodemographic variables were also recorded. RESULTS: There were significantly higher hair cortisol levels and perceived stress scale (PSS) scores in individuals with dental caries experience (DMFT≥1) than in those without (DMFT = 0). However, there was no significant difference in salivary cortisol concentration. A binary logistic regression revealed that higher hair cortisol levels and greater scores on the perceived stress scale were associated with increased odds of having experienced dental caries. In contrast, no significant association was found between salivary cortisol concentration and dental caries. Using multivariable regression models, caries experience was found to be significantly associated with both hair cortisol levels and PSS scores. These associations remained statistically significant even after adjusting for sociodemographic variables. CONCLUSION: Hair cortisol levels and perceived stress have a significant association with dental caries experience, whereas salivary cortisol concentrations do not.

3.
Methods ; 203: 249-258, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34737032

RESUMO

G protein-coupled receptors (GPCRs) are an important receptor superfamily and common therapeutic targets. The second messenger cyclic adenosine monophosphate (cAMP) is a key mediator in many GPCR signaling pathways. Monitoring intracellular cAMP levels can help identify orthosteric agonists and antagonists, as well as allosteric modulators. In this regard, luminescence-based biosensors have revolutionized our ability to monitor GPCR signaling kinetics. The GloSensor™ cAMP assay enables real-time monitoring of signaling downstream of many GPCRs. However, it is crucial to optimize assay conditions such as temperature. As well, it has not been reported whether the effects of temperature on biosensor activity are reversible. Here, we describe the temperature sensitivity and reversibility of the GloSensor™ cAMP assay, and which GloSensor™ version is optimal for measuring cytosolic cAMP. We also present a detailed protocol for monitoring cAMP levels in live cells expressing endogenous or exogenous GPCRs. Temperature optimization studies were carried out using HEK293H cells transiently transfected with the adenosine receptor A2a and the GloSensor™ plasmid (pGloSensor-20F or -22F). We found that preincubation and luminescence reading at room temperature were optimal as compared to higher temperatures. As well, the GloSensor-22F biosensor had a superior signal-to-background ratio and the effect of temperature on biosensor activity was reversible. However, thermal instability of the biosensor may pose a problem for in vivo studies. Nevertheless, the GloSensor™ cAMP assay can be applied to analyze signaling by a wide range of GPCRs for drug discovery purposes.


Assuntos
AMP Cíclico , Receptores Acoplados a Proteínas G , Bioensaio , AMP Cíclico/análise , AMP Cíclico/metabolismo , Cinética , Luciferases/genética , Luciferases/metabolismo , Receptores Acoplados a Proteínas G/genética , Temperatura
4.
BMC Womens Health ; 23(1): 431, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37580761

RESUMO

BACKGROUND: Urogynaecological conditions, such as pelvic organ prolapse, urinary incontinence, and urinary tract infection, can have a profound impact on people's lives. The Independent Medicines and Medical Devices Safety Review highlights missed opportunities to prevent harm when patient voices are not incorporated into healthcare policy and practice. This resonates with the Women's Health Strategy for England. The National Institute for Health and Care Research (NIHR) Policy Research Programme funded this in-depth qualitative exploration of people's experiences of living with urogynaecological conditions, and of seeking healthcare treatment, to inform health and social care improvements in the UK. METHODS: We conducted in-depth interviews online or by telephone (April 2021-December 2021) and used reflexive thematic analysis to develop themes that cut across urogynaecological conditions. RESULTS: We spoke to seventy-four adults aged 22-84 across a range of backgrounds and lived experiences of urogynaecological conditions, including pelvic organ prolapse, urinary incontinence and persistent or recurring urinary tract infection. Eight themes were developed: [1] I get no respite from my own body; [2] I feel confined and separated; [3] I can no longer be 'me'; [4] I am constrained by stigma, shame and silence; [5] I feel fragmented and lost in the healthcare system; [6] I need to be heard, believed, and valued; [7] I need respect as an equal partner in healthcare; and [8] (Re)connected to a more open community. CONCLUSIONS: High quality care focuses on the whole person rather than their body parts. Openness and candour support a shared decision-making model of care. A culture of shame can have a negative impact on access to health care and recovery.


Assuntos
Prolapso de Órgão Pélvico , Incontinência Urinária , Adulto , Humanos , Feminino , Pesquisa Qualitativa , Incontinência Urinária/terapia , Atenção à Saúde , Prolapso de Órgão Pélvico/terapia , Reino Unido
5.
Ultrasound Obstet Gynecol ; 58(2): 293-302, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32798253

RESUMO

OBJECTIVES: Preterm birth (PTB) accounts for two-thirds of deaths of structurally normal babies and is associated with substantial lifetime healthcare costs. Prevention of PTB remains limited by the modest accuracy of prediction methods, namely transvaginal ultrasound (TVS) cervical length (CL) measurement and quantitative cervicovaginal fetal fibronectin (FFN) estimation. We report the first substantive study detailing the predictive performance of a cervical probe device based on electrical impedance spectroscopy (EIS) for PTB - the EleCtriCaL Impedance Prediction of Preterm birth by spectroscopy of the cervix (ECCLIPPx) study. We aimed to compare the accuracy of cervical EIS-based prediction of spontaneous PTB with that of prediction using TVS-CL and FFN in asymptomatic women in the mid-trimester. METHODS: We studied asymptomatic women with a singleton pregnancy at 20-22 weeks' and 26-28 weeks' gestation. EIS was performed using a Sheffield Mark 5.0 device that makes measurements in the frequency range 76 Hz to 625 kHz using a small probe housing tetrapolar electrodes. TVS-CL and FFN were also measured. The associations of cervical EIS, TVS-CL and FFN with spontaneous delivery before 37 weeks and before 32 weeks were determined by multivariate linear and non-linear logistic regression analysis. Areas under the receiver-operating-characteristics curves (AUC) plots of sensitivity against specificity were used to compare the predictive performance of all parameters, both in isolation and in combination. RESULTS: Of the 365 asymptomatic women studied at 20-22 weeks who were not receiving treatment, 29 had spontaneous PTB, 14 had indicated PTB and 322 had term birth. At the higher frequencies assessed, cervical EIS predicted spontaneous PTB before 37 weeks with an AUC of 0.76 (95% CI, 0.71-0.81), compared with AUCs of 0.72 (95% CI, 0.66-0.76) for TVS-CL and 0.62 (95% CI, 0.56-0.72) for FFN. Combining all three assessments improved the prediction of spontaneous PTB before 37 weeks (AUC, 0.79 (95% CI, 0.74-0.83)) compared with TVS-CL and FFN alone. Incorporating a history of spontaneous PTB (defined as previous mid-trimester miscarriage or spontaneous PTB (14 to < 37 weeks)) into the cervical EIS prediction model improved the accuracy of prediction of spontaneous PTB before 37 weeks (AUC, 0.83 (95% CI, 0.78-0.87)) and before 32 weeks (AUC, 0.86 (95% CI, 0.82-0.90)). CONCLUSIONS: Mid-trimester cervical EIS assessment predicts spontaneous PTB. Larger confirmatory studies investigating its potential clinical utility and to inform effective preventive interventions are required. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Colo do Útero/diagnóstico por imagem , Nascimento Prematuro/prevenção & controle , Diagnóstico Pré-Natal , Adulto , Medida do Comprimento Cervical , Estudos de Coortes , Espectroscopia Dielétrica , Feminino , Humanos , Gravidez , Estudos Prospectivos , Sensibilidade e Especificidade
6.
BMC Fam Pract ; 22(1): 246, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34911451

RESUMO

BACKGROUND: Little is known about clinicians' perspectives on the use of point of care (POC) tests in assessment of acute illness during primary care out of hours (OOH) care. During a service improvement project, POC tests (including creatinine, electrolytes, haemoglobin and lactate) were made available to clinicians undertaking OOH home visits, with the clinicians allowed absolute discretion about when and whether they used them. METHOD: To explore clinicians' perspectives on having POC tests available during OOH home visits, we undertook a qualitative study with clinicians working in Oxfordshire OOH home visiting teams. We conducted 19 Semi-structured interviews with clinicians working in OOH, including those who had and had not used the POC tests available to them. To explore evolving perspectives over time, including experience and exposure to POC tests, we offered clinicians the opportunity to be interviewed twice throughout the study period. Our sample included 7 GPs (4 interviewed once, 3 interviewed twice - earlier and later during the study), 6 emergency practitioners (EPs) including advanced nurse practitioners and paramedics, 1 Healthcare Assistant, and 2 ambulatory care physicians. Interviews were audio-recorded, transcribed verbatim and analysed thematically. RESULTS: The clinicians reflected on their decision-making to use (or not use) POC tests, including considering which clinical scenarios were "appropriate" and balancing the resources and time taken to do POC tests against what were perceived as likely benefits. The challenges of using the equipment in patients' homes was a potential barrier, though could become easier with familiarity and experience. Clinicians who had used POC tests described benefits, including planning onward care trajectories, and facilitating communication, both between professionals and with patients and their families. CONCLUSION: Clinicians described a discriminatory approach to using POC tests, considering carefully in which situations they were likely to add value to clinical decision-making.


Assuntos
Plantão Médico , Visita Domiciliar , Humanos , Testes Imediatos , Atenção Primária à Saúde , Pesquisa Qualitativa
7.
J Cell Physiol ; 235(6): 5096-5110, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31696507

RESUMO

Low-magnitude high-frequency mechanical vibration induces biological responses in many tissues. Like many cell types, osteoblasts respond rapidly to certain forms of mechanostimulation, such as fluid shear, with transient elevation in the concentration of cytosolic free calcium ([Ca2+ ]i ). However, it is not known whether vibration of osteoblastic cells also induces acute elevation in [Ca2+ ]i . To address this question, we built a platform for vibrating live cells that is compatible with microscopy and microspectrofluorometry, enabling us to observe immediate responses of cells to low-magnitude high-frequency vibrations. The horizontal vibration system was mounted on an inverted microscope, and its mechanical performance was evaluated using optical tracking and accelerometry. The platform was driven by a sinusoidal signal at 20-500 Hz, producing peak accelerations from 0.1 to 1 g. Accelerometer-derived displacements matched those observed optically within 10%. We then used this system to investigate the effect of acceleration on [Ca2+ ]i in rodent osteoblastic cells. Cells were loaded with fura-2, and [Ca2+ ]i was monitored using microspectrofluorometry and fluorescence ratio imaging. No acute changes in [Ca2+ ]i or cell morphology were detected in response to vibration over the range of frequencies and accelerations studied. However, vibration did attenuate Ca2+ transients generated subsequently by extracellular ATP, which activates P2 purinoceptors and has been implicated in mechanical signaling in bone. In summary, we developed and validated a motion-control system capable of precisely delivering vibrations to live cells during real-time microscopy. Vibration did not elicit acute elevation of [Ca2+ ]i , but did desensitize responses to later stimulation with ATP.


Assuntos
Trifosfato de Adenosina/farmacologia , Cálcio/metabolismo , Mecanotransdução Celular/efeitos dos fármacos , Osteoblastos/metabolismo , Acelerometria , Trifosfato de Adenosina/metabolismo , Animais , Movimento Celular/efeitos dos fármacos , Citosol/efeitos dos fármacos , Citosol/metabolismo , Camundongos , Receptores Purinérgicos P2/genética , Vibração/efeitos adversos
8.
Br J Surg ; 107(5): 595-605, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32149386

RESUMO

BACKGROUND: Evidence is emerging that the incidence of colorectal cancer is increasing in young adults, but the descriptive epidemiology required to better understand these trends is currently lacking. METHODS: A population-based cohort study was carried out including all adults aged 20-49 years diagnosed with colorectal cancer in England between 1974 and 2015. Data were extracted from the National Cancer Registration and Analysis Service database using ICD-9/10 codes for colorectal cancer. Temporal trends in age-specific incidence rates according to sex, anatomical subsite, index of multiple deprivation quintile and geographical region were analysed using Joinpoint regression. RESULTS: A total of 56 134 new diagnoses of colorectal cancer were analysed. The most sustained increase in incidence rate was in the group aged 20-29 years, which was mainly driven by a rise in distal tumours. The magnitude of incident rate increases was similar in both sexes and across Index of Multiple Deprivation quintiles, although the most pronounced increases in incidence occurred in the southern regions of England. CONCLUSION: Colorectal cancer should no longer be considered a disease of older people. Changes in incidence rates should be used to inform future screening policy, preventative strategies and research agendas, as well as increasing public understanding that younger people need to be aware of the symptoms of colorectal cancer.


ANTECEDENTES: Están apareciendo evidencias de que la incidencia del cáncer colorrectal (colorectal cancer, CRC) está aumentando en adultos jóvenes, pero se carece de la epidemiología descriptiva necesaria para comprender mejor estas tendencias. MÉTODOS: Se realizó un estudio de cohortes de base poblacional de todos los adultos de 20 a 49 años diagnosticados de CRC en Inglaterra entre 1974 y 2015. Los datos se extrajeron de la base de datos NCRAS utilizando los códigos ICD9/10 para el CRC. Las tendencias temporales en las tasas de incidencia específicas por edad (incidence rates, IR) según el sexo, la localización anatómica, el quintil del índice de privación múltiple (index of multiple deprivation, IMD) y la región geográfica se analizaron mediante un modelo de regresión joinpoint. RESULTADOS: Se analizaron un total de 56.134 nuevos diagnósticos de CRC. El aumento más sostenido en la IR se produjo en el grupo de edad de 20 a 29 años, principalmente a expensas de un incremento de los tumores distales. La magnitud de los aumentos de IR fue similar en ambos sexos y en los quintiles del IMD, aunque los aumentos más pronunciados en la incidencia se registraron en las regiones del sur de Inglaterra. CONCLUSIÓN: El CRC ya no debe ser considerado una enfermedad de las personas mayores: los cambios en las tasas de incidencia deberán tenerse en cuenta en las futuras políticas de cribado, en las estrategias preventivas y en los proyectos de investigación, así como para aumentar la toma de conciencia de la población de que las personas más jóvenes deben estar al corriente de los síntomas del CRC.


Assuntos
Neoplasias Colorretais/epidemiologia , Adulto , Distribuição por Idade , Idade de Início , Neoplasias Colorretais/patologia , Inglaterra/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Vigilância da População , Sistema de Registros , Distribuição por Sexo , Adulto Jovem
9.
Colorectal Dis ; 22(12): 2087-2097, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32926531

RESUMO

AIM: Advanced stage presentation of colorectal cancer is associated with poorer survival outcomes, particularly among young adults. This study aimed to determine whether demographic risk factors for advanced stage presentation differed between young and older adults. METHOD: Individual-level data on all incident colorectal cancers in people aged 20 years and above were extracted from the National Cancer Registration and Analysis Service database for the years 2012 to 2015. Patients were divided into two cohorts: young-onset colorectal cancer (YOCC) if aged 20-49 years and older-onset colorectal cancer (OOCC) if aged 50 years and above. Logistic regression was used to identify risk factors for advanced stage presentation, defined as TNM Stage III or IV, in each cohort. RESULTS: There were 7075 (5.2%) patients in the YOCC cohort and 128 345 (94.8%) patients in the OOCC cohort. Tumours in the YOCC cohort were more likely to be at an advanced stage (67.2% vs 55.3%, P < 0.001) and located distally (63.7% vs 55.4%, P < 0.001). No demographic factor was consistently associated with advanced stage presentation in the YOCC cohort. Among the OOCC cohort, increased social deprivation [OR (Index of Multiple Deprivation quintile 5 vs 1) = 1.11 (95% CI 1.07-1.16), P < 0.001], Black/Black British ethnicity [OR (baseline White) = 1.25 (95% CI 1.11-1.40), P < 0.001] and residence in the East Midlands [OR (baseline London) = 1.11 (95% CI 1.04-1.17), P = 0.001] were associated with advanced stage presentation. CONCLUSION: Demographic factors associated with advanced disease were influenced by age. The effects of social deprivation and ethnicity were only observed in older adults and mirror trends in screening uptake. Targeted interventions for high-risk groups are warranted.


Assuntos
Neoplasias Colorretais , Idoso , Estudos de Coortes , Neoplasias Colorretais/epidemiologia , Inglaterra/epidemiologia , Etnicidade , Humanos , Fatores de Risco
10.
J Cell Physiol ; 234(8): 13705-13719, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31010267

RESUMO

Mice lacking equilibrative nucleoside transporter 1 (ENT1 -/- ) demonstrate progressive calcification of spinal tissues including the annulus fibrosus (AF) of the intervertebral disc (IVD). We previously established ENT1 as the primary nucleoside transporter in the AF and demonstrated dysregulation of biomineralization pathways. To identify cellular pathways altered by loss of ENT1, we conducted microarray analysis of AF tissue from wild-type (WT) and ENT1 -/- mice before calcification (2 months of age) and associated with calcification (6 months of age). Bioinformatic analyses identified cell cycle dysregulation in ENT1 -/- AF tissues and implicated the E2f family of transcription factors as potential effectors. Quantitative polymerase chain reaction analysis confirmed increased expression of multiple E2f transcription factors and E2f interacting proteins ( Rb1 and Cdk2) in ENT1 -/- AF cells compared with WT at 6 months of age. At this time point, ENT1 -/- AF tissues showed increased JNK MAPK pathway activation, CDK1, minichromosome maintenance complex component 5 (Mcm5), and proliferating cell nuclear antigen (PCNA) protein expression, and PCNA-positive proliferating cells compared with WT controls. The current study demonstrates that loss of ENT1-mediated adenosine transport leads to increased cell proliferation in the AF of the IVD.


Assuntos
Anel Fibroso/metabolismo , Anel Fibroso/patologia , Transportador Equilibrativo 1 de Nucleosídeo/metabolismo , Adenosina/metabolismo , Animais , Calcinose/metabolismo , Proliferação de Células/fisiologia , Camundongos , Camundongos Knockout
11.
Am J Transplant ; 17(6): 1585-1593, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28068455

RESUMO

In the United States, kidney transplant rates vary significantly across end-stage renal disease (ESRD) networks. We conducted a population-based cohort study to determine whether there was variability in kidney transplant rates across renal programs in a health care system distinct from the United States. We included incident chronic dialysis patients in Ontario, Canada, from 2003 to 2013 and determined the 1-, 5-, and 10-year cumulative incidence of kidney transplantation in 27 regional renal programs (similar to U.S. ESRD networks). We also assessed the cumulative incidence of kidney transplant for "healthy" dialysis patients (aged 18-50 years without diabetes, coronary disease, or malignancy). We calculated standardized transplant ratios (STRs) using a Cox proportional hazards model, adjusting for patient characteristics (maximum possible follow-up of 11 years). Among 23 022 chronic dialysis patients, the 10-year cumulative incidence of kidney transplantation ranged from 7.4% (95% confidence interval [CI] 4.8-10.7%) to 31.4% (95% CI 16.5-47.5%) across renal programs. Similar variability was observed in our healthy cohort. STRs ranged from 0.3 (95% CI 0.2-0.5) to 1.5 (95% CI 1.4-1.7) across renal programs. There was significant variation in kidney transplant rates across Ontario renal programs despite patients having access to the same publicly funded health care system.


Assuntos
Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Falência Renal Crônica/cirurgia , Transplante de Rim/métodos , Sistema de Registros/estatística & dados numéricos , Diálise Renal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Ontário , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
12.
Osteoarthritis Cartilage ; 25(5): 779-789, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28104539

RESUMO

OBJECTIVE: Whole-body vibration (WBV) is a popular fitness trend based on claims of increased muscle mass, weight loss and reduced joint pain. Following its original implementation as a treatment to increase bone mass in patients with osteoporosis, WBV has been incorporated into clinical practice for musculoskeletal disorders, including back pain. However, our recent studies revealed damaging effects of WBV on joint health in a murine model. In this report, we examined potential mechanisms underlying disc degeneration following exposure of mice to WBV. METHODS: Ten-week-old male mice were exposed to WBV (45 Hz, 0.3 g peak acceleration, 30 min/day, 5 days/week) for 4 weeks, 8 weeks, or 4 weeks WBV followed by 4 weeks recovery. Micro-computed tomography (micro-CT), histological, and gene expression analyses were used to assess the effects of WBV on spinal tissues. RESULTS: Exposure of mice to 4 or 8 weeks of WBV did not alter total body composition or induce significant changes in vertebral bone density. On the other hand, WBV-induced intervertebral disc (IVD) degeneration, associated with decreased disc height and degenerative changes in the annulus fibrosus (AF) that did not recover within 4 weeks after cessation of WBV. Gene expression analysis showed that WBV for 8 weeks induced expression of Mmp3, Mmp13, and Adamts5 in IVD tissues, changes preceded by increased expression of Il-1ß. CONCLUSIONS: Progressive IVD degeneration induced by WBV was associated with increased expression of Il-1ß within the IVD that preceded Mmp and Adamts gene induction. Moreover, WBV-induced IVD degeneration is not reversed following cessation of vibration.


Assuntos
Interleucina-1beta/genética , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Metaloproteinases da Matriz/genética , Vibração/efeitos adversos , Animais , Biópsia por Agulha , Modelos Animais de Doenças , Progressão da Doença , Regulação da Expressão Gênica , Imuno-Histoquímica , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/etiologia , Masculino , Camundongos , Camundongos Endogâmicos , Distribuição Aleatória , Valores de Referência , Microtomografia por Raio-X/métodos
13.
Osteoarthritis Cartilage ; 25(5): 770-778, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27840128

RESUMO

OBJECTIVE: Low-amplitude, high-frequency whole-body vibration (WBV) has been adopted for the treatment of musculoskeletal diseases including osteoarthritis (OA); however, there is limited knowledge of the direct effects of vibration on joint tissues. Our recent studies revealed striking damage to the knee joint following exposure of mice to WBV. The current study examined the effects of WBV on specific compartments of the murine tibiofemoral joint over 8 weeks, including microarchitecture of the tibia, to understand the mechanisms associated with WBV-induced joint damage. DESIGN: Ten-week-old male CD-1 mice were exposed to WBV (45 Hz, 0.3 g peak acceleration; 30 min/day, 5 days/week) for 4 weeks, 8 weeks, or 4 weeks WBV followed by 4 weeks recovery. The knee joint was evaluated histologically for tissue damage. Architecture of the subchondral bone plate, subchondral trabecular bone, primary and secondary spongiosa of the tibia was assessed using micro-CT. RESULTS: Meniscal tears and focal articular cartilage damage were induced by WBV; the extent of damage increased between 4 and 8-week exposures to WBV. WBV did not alter the subchondral bone plate, or trabecular bone of the tibial spongiosa; however, a transient increase was detected in the subchondral trabecular bone volume and density. CONCLUSIONS: The lack of WBV-induced changes in the underlying subchondral bone suggests that damage to the articular cartilage may be secondary to the meniscal injury we detected. Our findings underscore the need for further studies to assess the safety of WBV in the human population to avoid long-term joint damage.


Assuntos
Cartilagem Articular/lesões , Traumatismos do Joelho/patologia , Tíbia/patologia , Vibração/efeitos adversos , Animais , Biópsia por Agulha , Cartilagem Articular/patologia , Modelos Animais de Doenças , Imuno-Histoquímica , Traumatismos do Joelho/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos , Valores de Referência , Microtomografia por Raio-X
14.
Osteoarthritis Cartilage ; 25(3): 421-425, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27720885

RESUMO

OBJECTIVE: Whole-body vibration (WBV) platforms are commercially available devices that are used clinically to treat numerous musculoskeletal conditions based on their reported ability to increase bone mineral density and muscle strength. Despite widespread use, there is an alarming lack of understanding of the direct effects of WBV on joint health. Previous work by our lab demonstrated that repeated exposure to WBV using protocols that model those used clinically, induces intervertebral disc (IVD) degeneration and osteoarthritis-like damage in the knee of skeletally mature, male mice of a single outbred strain (CD-1). The present study examined whether exposure to WBV induces similar deleterious effects in a genetically different strain of mouse (C57BL/6). DESIGN: Male 10-week-old C57BL/6 mice were exposed to vertical sinusoidal WBV for 30 min/day, 5 days/week, for 4 or 8 weeks using previously reported protocols (45 Hz, 0.3 g peak acceleration). Following WBV, joint tissues were examined using histological analysis and gene expression was quantified using real-time PCR (qPCR). RESULTS: Our analyses show a lack of WBV-induced degeneration in either the knee or IVDs of C57BL/6 mice exposed to WBV for 4 or 8 weeks, in direct contrast to the WBV-induced damage previously reported by our lab in CD-1 mice. CONCLUSIONS: Together with previous studies from our group, the present study demonstrates that the effects of WBV on joint tissues vary in a strain-specific manner. These findings highlight the need to examine genetic or physiological differences that may underlie susceptibility to the deleterious effects of WBV on joint tissues.


Assuntos
Artropatias/etiologia , Camundongos Endogâmicos C57BL , Vibração/efeitos adversos , Animais , Disco Intervertebral/metabolismo , Disco Intervertebral/patologia , Artropatias/patologia , Articulações/metabolismo , Articulações/patologia , Vértebras Lombares , Masculino , Camundongos , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma
15.
Indoor Air ; 27(2): 463-477, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27490066

RESUMO

Ventilation standards, health, and indoor air quality have not been adequately examined for residential weatherization. This randomized trial showed how ASHRAE 62-1989 (n=39 houses) and ASHRAE 62.2-2010 (n=42 houses) influenced ventilation rates, moisture balance, indoor air quality, and self-reported physical and mental health outcomes. Average total airflow was nearly twice as high for ASHRAE 62.2-2010 (79 vs. 39 cfm). Volatile organic compounds, formaldehyde and carbon dioxide were all significantly reduced for the newer standard and first-floor radon was marginally lower, but for the older standard, only formaldehyde significantly decreased. Humidity in the ASHRAE 62.2-2010 group was only about half that of the ASHRAE 62-1989 group using the moisture balance metric. Radon was higher in the basement but lower on the first floor for ASHRAE 62.2-2010. Children in each group had fewer headaches, eczema, and skin allergies after weatherization and adults had improvements in psychological distress. Indoor air quality and health improve when weatherization is accompanied by an ASHRAE residential ventilation standard, and the 2010 ASHRAE standard has greater improvements in certain outcomes compared to the 1989 standard. Weatherization, home repair, and energy conservation projects should use the newer ASHRAE standard to improve indoor air quality and health.


Assuntos
Aclimatação , Poluição do Ar em Ambientes Fechados/análise , Habitação/normas , Ventilação/normas , Tempo (Meteorologia) , Adulto , Poluição do Ar em Ambientes Fechados/efeitos adversos , Dióxido de Carbono/análise , Criança , Feminino , Formaldeído/análise , Humanos , Masculino , Radônio/análise , Ventilação/métodos , Compostos Orgânicos Voláteis/análise
16.
Clin Exp Ophthalmol ; 45(5): 520-528, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28013525

RESUMO

BACKGROUND: Microinvasive glaucoma surgery (MIGS) is a relatively new addition to the glaucoma treatment paradigm. Small metallic stents are inserted into the trabecular meshwork in order to increase aqueous humour drainage. MIGS procedures are rapidly being adopted owing to a more favourable side effect profile when compared with traditional surgery. Remarkably, this rapid rate of utilization has occurred without any published studies on the effect of metal alloys used in these stents on human trabecular meshwork cells (HTMCs). Therefore, this study aimed to determine the effect of candidate metal alloys for MIGS on HTMC morphology, viability and function. METHODS: Human trabecular meshwork cells were cultured on the surfaces of titanium (polished and sandblasted), a titanium-nickel (nitinol) alloy and glass (as control substratum). Fluorescence imaging was used to assess cell morphology and spreading. A lactate dehydrogenase cytotoxicity assay, cell death detection ELISA, MTT cell viability assay, BrdU cell proliferation assay and fibronectin ELISA were also conducted. RESULTS: Cells cultured on sandblasted titanium exhibited significantly greater spreading than cells cultured on other substrata. In comparison, HTMCs cultured on nitinol displayed poor spreading. Significantly more cell death, by both necrosis and apoptosis, occurred on nitinol than on titanium and glass. Also, cell viability and proliferation were suppressed on nitinol compared with titanium or glass. Finally, HTMCs on both titanium and nitinol produced greater amounts of fibronectin than cells grown on glass. CONCLUSIONS: Substratum topography and metal alloy composition were found to impact morphology, viability and function of primary HTMC cultures.


Assuntos
Ligas/farmacologia , Cirurgia Filtrante/métodos , Implantes para Drenagem de Glaucoma , Glaucoma/patologia , Procedimentos Cirúrgicos Minimamente Invasivos , Malha Trabecular/ultraestrutura , Apoptose , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Colorimetria , Ensaio de Imunoadsorção Enzimática , Glaucoma/metabolismo , Glaucoma/cirurgia , Humanos , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Malha Trabecular/efeitos dos fármacos , Malha Trabecular/metabolismo
17.
Implant Dent ; 26(2): 225-231, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27918313

RESUMO

PURPOSE: Mechanical loosening remains a common complication associated with mini-implant failure. The purpose of this study was to compare common mechanical measures of mini-implant stability to determine their association and reliability. MATERIALS AND METHODS: Ninety self-drilling orthodontic mini-implants from 6 manufacturers were inserted into artificial bone blocks. Insertion torques (ITs) and Periotest values (PVs) were measured. Subsequently, mini-implants underwent pull-out testing for measures of pull-out load (POL) and screw displacement (ScrD). Stability measurements were compared using one-way ANOVA, associations among them were assessed using correlation analyses, and reliability was evaluated using coefficients of variation (COVs). RESULTS: Variations in stability of mini-implants were found, specific to the mechanical measure used for assessment (P < 0.05). The strongest correlations were found between IT and PV (r = -0.68) and between IT and POL (r = 0.66). Overall, PV showed the greatest variability (COV: 11%-100%) compared with IT (≤11%), POL (≤4%), and ScrD (≤19%). CONCLUSIONS: IT, PV, and POLs only agreed moderately in their assessment of mini-implant stability, and Periotest showed the least reliability in predicting mini-implant stability. As such, independent and interchangeable use of these stability measures should be avoided.


Assuntos
Implantes Dentários , Análise do Estresse Dentário/métodos , Falha de Restauração Dentária , Humanos , Procedimentos de Ancoragem Ortodôntica/métodos
18.
Br J Surg ; 103(11): 1557-65, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27517543

RESUMO

BACKGROUND: The weekend effect describes excess mortality associated with hospital admission on Saturday or Sunday. This study assessed whether a weekend effect exists for patients admitted for emergency general surgery. METHODS: Data for emergency general surgical admissions to National Health Service hospitals in the Northern Deanery in England between 2000 and 2014 were collected, including demographics, co-morbidities, diagnoses, operations undertaken and outcomes. The primary outcome of interest was in-hospital death within 30 days of admission. Cox regression analysis was undertaken with adjustment for co-variables. RESULTS: There were 12 100 in-hospital deaths within 30 days of admission (3·3 per cent). The overall 30-day mortality rate reduced significantly during the 15-year interval studied, from 5·4 per cent (2000-2004) to 4·0 per cent (2005-2009) and 2·9 per cent during 2010-2014 (P < 0·001). There was no significant mortality difference for patients admitted at the weekend in adjusted Cox models (hazard ratio (HR) 1·00 for Saturday and 0·90 for Sunday, versus Wednesday). There was a significantly higher mortality for operations undertaken at the weekend (HR 1·15 for Saturday and 1·40 for Sunday; P = 0·021 and P < 0·001 respectively). The significantly increased mortality that was evident for emergency surgery at the weekend compared with weekdays in 2000-2004 (HR 1·46 for Saturday and 1·55 for Sunday; both P < 0·001); had reduced by 2010-2014, when the adjusted mortality risk was not significant (HR 1·18 for Saturday and 1·12 for Sunday). CONCLUSION: During the past 15 years there has been a weekend effect in patients undergoing emergency general surgery based on day of operation, but not day of admission. Overall mortality for emergency general surgery has improved significantly, and in the past 5 years the increased mortality risk of weekend surgery has reduced.


Assuntos
Plantão Médico , Tratamento de Emergência/mortalidade , Procedimentos Cirúrgicos Operatórios/mortalidade , Adolescente , Adulto , Idoso , Serviço Hospitalar de Emergência/estatística & dados numéricos , Inglaterra , Feminino , Mortalidade Hospitalar , Hospitalização/estatística & dados numéricos , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
19.
Biomed Microdevices ; 18(5): 78, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27523472

RESUMO

We describe a simple fabrication technique - targeted towards non-specialists - that allows for the production of leak-proof polydimethylsiloxane (PDMS) microfluidic devices that are compatible with live-cell microscopy. Thin PDMS base membranes were spin-coated onto a glass-bottom cell culture dish and then partially cured via microwave irradiation. PDMS chips were generated using a replica molding technique, and then sealed to the PDMS base membrane by microwave irradiation. Once a mold was generated, devices could be rapidly fabricated within hours. Fibronectin pre-treatment of the PDMS improved cell attachment. Coupling the device to programmable pumps allowed application of precise fluid flow rates through the channels. The transparency and minimal thickness of the device enabled compatibility with inverted light microscopy techniques (e.g. phase-contrast, fluorescence imaging, etc.). The key benefits of this technique are the use of standard laboratory equipment during fabrication and ease of implementation, helping to extend applications in live-cell microfluidics for scientists outside the engineering and core microdevice communities.


Assuntos
Dispositivos Lab-On-A-Chip , Microscopia/instrumentação , Células 3T3 , Animais , Sobrevivência Celular , Dimetilpolisiloxanos , Desenho de Equipamento , Hidrodinâmica , Camundongos , Nylons
20.
Purinergic Signal ; 12(3): 509-20, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27206526

RESUMO

The P2X7 and Wnt/ß-catenin signaling pathways regulate osteoblast differentiation and are critical for the anabolic responses of bone to mechanical loading. However, whether these pathways interact to control osteoblast activity is unknown. The purpose of this study was to investigate the effects of P2X7 activation on Wnt/ß-catenin signaling in osteoblasts. Using MC3T3-E1 cells, we found that combined treatment with Wnt3a and the P2X7 agonist 2'(3')-O-(4-benzoylbenzoyl)adenosine 5'-triphosphate (BzATP) elicited more sustained ß-catenin nuclear localization than that induced by Wnt3a alone. Wnt3a-induced increases in ß-catenin transcriptional activity were also potentiated by treatment with BzATP. Consistent with involvement of P2X7, a high ATP concentration (1 mM) potentiated Wnt3a-induced ß-catenin transcriptional activity, whereas a low concentration (10 µM) of ATP, adenosine 5'-diphosphate (ADP), or uridine 5'-triphosphate (UTP) failed to elicit a response. The potentiation of ß-catenin transcriptional activity elicited by BzATP was also inhibited by two distinct P2X7 antagonists: A 438079 and A 740003. Furthermore, responses to Wnt3a in calvarial cells isolated from P2rx7 knockout mice were significantly less than in cells from wild-type controls. In MC3T3-E1 cells, BzATP increased inhibitory phosphorylation of glycogen synthase kinase 3ß (GSK3ß), a process that was blocked by A 438079 and diminished by inhibition of protein kinase C. Thus, P2X7 signaling may potentiate the canonical Wnt pathway through GSK3ß inhibition. Taken together, we show that P2X7 activation prolongs and potentiates Wnt/ß-catenin signaling. Consequently, cross-talk between P2X7 and Wnt/ß-catenin pathways may modulate osteoblast activity in response to mechanical loading.


Assuntos
Osteoblastos/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Via de Sinalização Wnt/fisiologia , Animais , Western Blotting , Imunofluorescência , Camundongos , Camundongos Knockout
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