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1.
Nature ; 595(7869): 661-666, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34321672

RESUMO

Strange metals possess highly unconventional electrical properties, such as a linear-in-temperature resistivity1-6, an inverse Hall angle that varies as temperature squared7-9 and a linear-in-field magnetoresistance10-13. Identifying the origin of these collective anomalies has proved fundamentally challenging, even in materials such as the hole-doped cuprates that possess a simple bandstructure. The prevailing consensus is that strange metallicity in the cuprates is tied to a quantum critical point at a doping p* inside the superconducting dome14,15. Here we study the high-field in-plane magnetoresistance of two superconducting cuprate families at doping levels beyond p*. At all dopings, the magnetoresistance exhibits quadrature scaling and becomes linear at high values of the ratio of the field and the temperature, indicating that the strange-metal regime extends well beyond p*. Moreover, the magnitude of the magnetoresistance is found to be much larger than predicted by conventional theory and is insensitive to both impurity scattering and magnetic field orientation. These observations, coupled with analysis of the zero-field and Hall resistivities, suggest that despite having a single band, the cuprate strange-metal region hosts two charge sectors, one containing coherent quasiparticles, the other scale-invariant 'Planckian' dissipators.

2.
Opt Lett ; 48(16): 4324-4327, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37582023

RESUMO

A high-peak-power sub-500-fs mode-locked optically pumped semiconductor laser is innovatively developed with only three components of a semiconductor gain chip, a semiconductor saturable absorber, and a focusing lens. The developed laser near the threshold pump power of 3.9 W can be operated with stable fundamental mode locking. The laser output can be naturally turned into the stable harmonic mode locking (HML) with the order gradually changing from 2nd to 8th by increasing the pump power from 4.0 W to 5.0 W. Due to the onset of the high-order transverse modes, the order of HML is fixed at 8th for a pump power greater than 5.0 W. For the HML with order less than 8th, the overall peak power and pulse width in the HML are approximately 0.36 kW and 550 fs, respectively. In the operation of 8th-order HML, the minimum pulse width and maximum peak power can reach 480 fs and 0.95 kW, respectively.

3.
Osteoarthritis Cartilage ; 29(5): 718-727, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33577958

RESUMO

OBJECTIVE: The vascularization of subchondral bone plays a significant role in the progression of knee osteoarthritis (OA). Treatment with platelet-rich plasma (PRP) has positive effects on cartilage lesions. However, PRP's efficacy for subchondral bone marrow lesions and the relationship of these lesions to cartilage are still undiscovered. Therefore, our aims were first to longitudinally investigate the change in subchondral flow by dynamic contrast enhanced MRI and degeneration of cartilage by MRI T2∗ in an anterior cruciate transection rodent (ACLT) model, and second to examine changes in parameters after intra-articular PRP injection. DESIGN: A 32-week investigation in 18 rats allocated to sham-control, ACLT with normal saline injection (ACLT + NS), and ACLT with PRP injection groups ended with histological evaluation. Another rat was used as a donor of allogenic PRP. RESULTS: Compared to the sham-control group, the ACLT + NS group had higher subchondral blood volume A (0.051, 95% confidence interval: 0.009, 0.092) and lower venous washout kel (-0.030: -0.055, -0.005) from week 4; lower permeability kep from week 18 (-0.954: -1.339, -0.569); higher cartilage T2∗ values (1.803: 1.504, 2.102) reflecting collagen loss beginning at week 10. For the PRP treatment group, subchondral bone marrow A and cartilage T2∗ decreased from week 10. Histological results confirmed and were correlated with the MRI findings. CONCLUSION: Subchondral hyper-perfusion plays a vital role in the pathogenesis of OA and was associated with cartilage degeneration. The efficacy of PRP can be observed from reduced perfusion and MRI T2∗ values.


Assuntos
Medula Óssea/irrigação sanguínea , Medula Óssea/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Imageamento por Ressonância Magnética , Plasma Rico em Plaquetas , Animais , Volume Sanguíneo , Modelos Animais de Doenças , Injeções Intra-Articulares , Osteoartrite/diagnóstico por imagem , Osteoartrite/terapia , Ratos Sprague-Dawley , Joelho de Quadrúpedes/irrigação sanguínea , Joelho de Quadrúpedes/diagnóstico por imagem
4.
Osteoporos Int ; 32(6): 1233-1237, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33575910

RESUMO

The authors present a rare case of multiple vertebral compression fractures in a young female with iatrogenic glucocorticoid-induced Cushing syndrome and concomitant human immunodeficiency virus (HIV) infection. Both long-term steroid use and HIV infection may lead to osteopenia or even osteoporosis. Multiple vertebral fractures in young patients are very uncommon and should alert the examiner to investigate any underlying cause. Treatment choices include pharmacological agents such as bisphosphonates or parathyroid hormone and even surgical interventions such as percutaneous vertebroplasty.


Assuntos
Síndrome de Cushing , Fraturas por Compressão , Infecções por HIV , Fraturas da Coluna Vertebral , Vertebroplastia , Síndrome de Cushing/induzido quimicamente , Feminino , Fraturas por Compressão/induzido quimicamente , Fraturas por Compressão/diagnóstico por imagem , Glucocorticoides/efeitos adversos , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Fraturas da Coluna Vertebral/induzido quimicamente , Fraturas da Coluna Vertebral/diagnóstico por imagem , Resultado do Tratamento , Vertebroplastia/efeitos adversos
5.
Osteoporos Int ; 32(5): 961-970, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33104822

RESUMO

Bone mineral density (BMD) may be increased due to vertebral compression fractures (VCF). Our study showed trabecular bone scores (TBS) was less affected than BMD by fractured vertebrae. The TBS of most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity, could still be used in predicting fracture risk. INTRODUCTION: Trabecular bone score (TBS), a noninvasive tool estimating bone microarchitecture, provides complementary information to lumbar spine bone mineral density (BMD). Lumbar spine BMD might be increased due to both degenerative disease and vertebral compression fractures (VCF). Lumbar spine TBS has been confirmed not influenced by osteoarthrosis, but the effects of VCF are still not been well evaluated. This study aimed to investigate whether lumbar spine TBS was affected by fractured vertebrae. METHODS: We studied postmenopausal women and men above 50 years old who underwent DXA between January 1, 2017, and May 31, 2019. By calculating the difference of BMD and TBS between L1 and the mean of L2-3, the study compared the difference of values between the control group and fracture group to determine the effects of fractured vertebrae on BMD and TBS. RESULTS: A total of 377 participants were enrolled with 202 in the control group (157 females; age: 68.06 ± 6.47 years) and 175 in the fracture group (147 females; age: 71.71 ± 9.44 years). The mean BMD of the L1 vertebrae in the fracture group was significantly higher than that in the control group (p < 0.0001). There was no significant difference between the mean differences of TBS between L1 and the means of L2-3 vertebrae in the control group and the most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity. CONCLUSION: Lumbar spine TBS, unlike BMD, is less affected by fractured vertebrae. The TBS of most compression fractures, including old and recent VCF with mild or moderate deformity and old VCF with severe deformity, could still be used in predicting fracture risk.


Assuntos
Fraturas por Compressão , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Osso Esponjoso/diagnóstico por imagem , Feminino , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/etiologia , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/etiologia , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/etiologia
6.
Public Health ; 182: 102-109, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32247105

RESUMO

OBJECTIVE: In the context of universal health insurance coverage, this study aimed to determine whether urban-rural inequality still exists in preventive health care (PHC) amongst children in Taiwan. STUDY DESIGN: Prospective cohort study. METHODS: A total of 184,117 mothers and their children born in 2009 were identified as the study cohort. The number of children born in urban, satellite and rural areas was 40,176, 57,565 and 86,805, respectively. All children were followed for 7 years, before which a total of seven times PHC were provided by Taiwan's National Health Insurance (NHI) programme. Ordinal logistic regression models were used to associate urbanisation level with the frequency of PHC utilisation. Stratified analyses were further performed in accordance with the children's birth weight and the mothers' birthplace. RESULTS: Children from satellite areas had higher utilisation for the first four scheduled PHC visits. Children living in urban areas received more PHC for the fifth and sixth scheduled visits. Compared with those from rural areas, children in satellite areas exhibited a small but significant increase in odds in PHC utilisation, with a covariate-adjusted odds ratio (aOR) of 1.04 and 95% confidence interval (CI) of 1.02-1.06. By contrast, no significant difference was observed between rural and urban areas (aOR = 1.01). Further stratified analyses suggest more evident urban-rural difference in PHC utilisation amongst children with low birth weight and foreign-born mothers. CONCLUSIONS: Given a universal health insurance coverage and embedded mechanisms in increasing the availability of healthcare resources in Taiwan, a slight urban-rural difference is observed in PHC utilisation amongst children. Hence, sociodemographic inequality in utilisation of PHC still exists. This issue should be addressed through policy intervention.


Assuntos
Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Serviços Preventivos de Saúde/estatística & dados numéricos , População Rural/estatística & dados numéricos , Cobertura Universal do Seguro de Saúde/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Disparidades em Assistência à Saúde , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Programas Nacionais de Saúde , Estudos Prospectivos , Fatores Socioeconômicos , Taiwan , Adulto Jovem
7.
Tech Coloproctol ; 24(11): 1197-1205, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32632708

RESUMO

BACKGROUND: The transvaginal natural orifice specimen extraction (NOSE) approach for right-side colon surgery has been proven to exhibit favorable short-term outcomes. However, thus far, no study has reported the advantages of transrectal NOSE for right-side colon surgery. The aim of this study was to compare the technical feasibility, safety, and short-term outcomes of minimally invasive right hemicolectomy using the transrectal NOSE method and those of conventional mini-laparotomy specimen extraction. METHODS: A study was conducted on consecutive patients who had minimally invasive right hemicolectomy either for malignancy or benign disease at Chang Gung Memorial Hospital, Linkou, Taiwan, between January 2017 and December 2018. The patients were divided into two groups: conventional surgery with specimen extraction using mini-laparotomy and NOSE surgery. Surgical outcomes, including complications, postoperative short-term recovery, and pain intensity, were analyzed. RESULTS: We enrolled 297 patients (151 males, mean age 64.9 ± 12.8 years) who had minimally invasive right hemicolectomy. Of these 297 patients, 272 patients had conventional surgery with specimen extraction through mini-laparotomy and 25 patients had NOSE surgery (23 transrectal, 2 transvaginal). The diagnosis of colon disease did not differ significantly between the conventional and NOSE groups. Postoperative morbidity and mortality rates were comparable. The postoperative hospital stay was significantly (p = 0.004) shorter in the NOSE group (median 5 days, range 3-17 days) than in the conventional group (median 7 days, range 3-45 days). Postoperative pain was significantly (p = 0.026 on postoperative day 1 and p = 0.002 on postoperative day 2) greater in the conventional group than in the NOSE group. CONCLUSIONS: NOSE was associated with acceptable short-term surgical outcomes that were comparable to those of conventional surgery. NOSE results in less postoperative wound pain and a shorter hospital stay than conventional surgery. Larger studies are needed.


Assuntos
Laparoscopia , Cirurgia Endoscópica por Orifício Natural , Idoso , Colectomia , Humanos , Laparotomia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
8.
Hong Kong Med J ; 25(6): 429-437, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31796644

RESUMO

INTRODUCTION: Although computed tomography (CT) is a useful tool for exploring occult infection in patients with sepsis in the emergency department, the potential nephrotoxicity of contrast media is a major concern. Our study aimed to investigate the association between use of contrast-enhanced CT and the risks of acute kidney injury and other adverse outcomes in patients with sepsis. METHODS: In total, 587 patients with sepsis who underwent CT scan (enhanced CT group: 105, non-enhanced CT group: 482) from January 2012 to December 2016 at a tertiary referral centre were enrolled in this retrospective analysis, and propensity score matching was performed to minimise the selection bias. The length of stay, incidences of acute kidney injury and emergent dialysis, and short-term mortality were compared between the two groups. RESULTS: Compared with patients in the non-enhanced CT group, patients in the contrast-enhanced CT group did not have increased risks of acute kidney injury (odds ratio [OR]=1.38, 95% confidence interval [CI]=0.55-3.43; P=0.489), emergent dialysis (OR=1.31, 95% CI=0.47-3.68; P=0.602), or short-term mortality (OR=0.90, 95% CI=0.48-1.69; P=0.751). In addition, there was no significant difference in the median length of hospital stay between survivors in the two groups (20 vs 19 days, P=0.742). CONCLUSIONS: Intravenous contrast administration during CT scanning was not associated with prolonged length of hospital stay in patients with sepsis in an emergency setting. Moreover, the use of contrast-enhanced CT was not associated with increased risks of acute kidney injury, emergent dialysis, or short-term mortality.


Assuntos
Injúria Renal Aguda/epidemiologia , Meios de Contraste/efeitos adversos , Sepse/diagnóstico por imagem , Injúria Renal Aguda/induzido quimicamente , Administração Intravenosa , Idoso , Estudos de Coortes , Meios de Contraste/administração & dosagem , Serviço Hospitalar de Emergência , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Estudos Retrospectivos , Fatores de Risco , Taiwan/epidemiologia , Tomografia Computadorizada por Raios X
9.
J Viral Hepat ; 25(5): 590-597, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29274189

RESUMO

This study investigates the incidences and predictors of hepatitis B virus (HBV) relapse after tenofovir disoproxil fumarate (TDF) therapy in hepatitis B e antigen (HBeAg)-positive and -negative patients. We retrospectively recruited 143 chronic hepatitis B (CHB) patients without cirrhosis (39 HBeAg-positive and 104 HBeAg-negative patients) who were previously treated with TDF and had post-treatment follow-up for at least 6 months (median: 55, IQR 36-85 weeks). All the patients fulfilled the stopping criteria of APASL 2012. The virological and clinical relapse rates at 104 weeks in HBeAg-positive patients were 66.6% and 59.1%, while they were 72.3% and 55.9%, respectively, in HBeAg-negative patients. Cox regression analysis revealed that the higher end-of-treatment HBsAg levels were an independent factor of virological relapse in HBeAg-positive and HBeAg-negative patients. The end-of-treatment HBsAg levels of 200 (area under the receiver operating characteristic (AUROC): 0.624) and 80 IU/mL (AUROC: 0.959) were the optimal values for predicting HBV relapse in HBeAg-positive and HBeAg-negative patients, respectively. The virological relapse rate at 78 weeks was 14.3% and 19.6% in HBeAg-positive and HBeAg-negative patients who achieved HBsAg ≤200 IU/mL and HBsAg ≤80 IU/mL, respectively. Two patients experienced hepatic decompensation upon hepatitis flares, and no patient died after timely retreatment. Seven patients experienced off-therapy HBsAg loss. The cumulative rates of HBsAg loss at 104 weeks were 45.5% and 59.3% in patients with end-of-treatment HBsAg ≤80 IU/mL and ≤50 IU/mL, respectively. In conclusions, the end-of-treatment HBsAg levels were a useful marker for predicting HBV relapse in HBeAg-positive and HBeAg-negative CHB patients.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/epidemiologia , Tenofovir/uso terapêutico , Adulto , Idoso , Feminino , Seguimentos , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Medição de Risco
10.
Osteoporos Int ; 29(4): 953-960, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29429033

RESUMO

PURPOSE: Although half of women and one-quarter of men aged 50 and older will sustain an acute low-trauma fracture, less than a quarter receive appropriate secondary fracture prevention. The goal of this quality improvement demonstration project was to implement a Fracture Liaison Service (FLS) focused on secondary prevention of an osteoporotic fracture in three open health care systems aided by a cloud-based tool. METHODS: The pre-post study design examined the proportion of men and women over age 50 who received appropriate assessment (bone mineral density, vitamin D levels) and treatment (calcium/vitamin D, pharmacologic therapy) in the six months following a recently diagnosed fracture. The pre-study (Pre FLS) included a retrospective chart review for baseline data (N = 344 patients) within each health care system. In the post-evaluation (Post FLS, N = 148 patients), the FLS coordinator from each health care system examined these parameters following enrollment and for 6 months following the recently diagnosed fracture. Data were managed in the cloud-based FLS application tool. RESULTS: Ninety-three participants completed the program. The FLS program increased the percentage of patients receiving bone mineral density testing from 21% at baseline to 93% (p < 0.001) Post FLS implementation. Assessments of vitamin D levels increased from 25 to 84% (p < 0.001). Patients prescribed calcium/vitamin D increased from 36% at baseline to 93% (p < 0.001) and those prescribed pharmacologic treatment for osteoporosis increased on average from 20 to 54% (p < 0.001) Post FLS. CONCLUSIONS: We conclude that the FLS model of care in an open health care system, assisted by a cloud-based tool, significantly improved assessment and/or treatment of patients with a recently diagnosed osteoporotic fracture. Future studies are necessary to determine if this model of care is scalable and if such programs result in prevention of fractures. Mini-Abstract: The goal was to implement a Fracture Liaison Service (FLS) focused on secondary prevention of an osteoporotic fracture in open health care systems aided by a cloud-based tool. This model significantly improved assessment and/or treatment of patients with a recently diagnosed fracture.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Modelos Organizacionais , Fraturas por Osteoporose/prevenção & controle , Absorciometria de Fóton/métodos , Idoso , Densidade Óssea/fisiologia , Conservadores da Densidade Óssea/uso terapêutico , Cálcio/uso terapêutico , Computação em Nuvem , Suplementos Nutricionais , Uso de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico , Osteoporose/tratamento farmacológico , Osteoporose/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Estudos Retrospectivos , Prevenção Secundária/organização & administração , Estados Unidos , Vitamina D/uso terapêutico
11.
J Evol Biol ; 31(1): 75-87, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29044885

RESUMO

How has evolution led to the variation in behavioural phenotypes (personalities) in a population? Knowledge of whether personality is heritable, and to what degree it is influenced by the social environment, is crucial to understanding its evolutionary significance, yet few estimates are available from natural populations. We tracked three behavioural traits during different life-history stages in a pedigreed population of wild house sparrows. Using a quantitative genetic approach, we demonstrated heritability in adult exploration, and in nestling activity after accounting for fixed effects, but not in adult boldness. We did not detect maternal effects on any traits, but we did detect a social brood effect on nestling activity. Boldness, exploration and nestling activity in this population did not form a behavioural syndrome, suggesting that selection could act independently on these behavioural traits in this species, although we found no consistent support for phenotypic selection on these traits. Our work shows that repeatable behaviours can vary in their heritability and that social context influences personality traits. Future efforts could separate whether personality traits differ in heritability because they have served specific functional roles in the evolution of the phenotype or because our concept of personality and the stability of behaviour needs to be revised.


Assuntos
Comportamento Animal/fisiologia , Pardais/fisiologia , Animais , Personalidade , Característica Quantitativa Herdável , Comportamento Social , Pardais/genética
12.
Public Health ; 159: 50-57, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29729491

RESUMO

OBJECTIVES: Healthcare professionals (HCPs) can help promote healthy eating and active living in patients. This study assessed the effects of weight-related advice from HCPs on change in body mass index (BMI) of patients in the USA. STUDY DESIGN: A 1-year follow-up study of 20,002 adults who participated in a nationally representative survey between 2004 and 2008. METHODS: Using the 2004-2008 Medical Expenditure Panel Survey data, 1-year BMI and weight status changes were compared between patients who did and did not report receiving advice on exercise or on restricted intake of fat and cholesterol from their HCPs. RESULTS: Patients who received weight-related advice had a greater increase in BMI compared with those who did not receive weight-related advice. Stratified by the baseline weight status of patients (i.e. normal weight, overweight or obese), adverse direction of BMI change was only significantly associated with advice on exercise. Patients who received advice to exercise more were more likely to move to a higher weight status than remaining at the same weight status, compared with patients who did not receive advice to exercise more. CONCLUSION: This study did not find that weight-related advice from HCPs had a positive impact on BMI loss in patients. On the contrary, patients who reported receiving weight-related advice from HCPs had worse weight outcomes 1 year later than patients who did not report receiving weight-related advice. Further research is warranted to elucidate the role of weight-related advice from HCPs on lifestyle change and obesity prevention and control.


Assuntos
Índice de Massa Corporal , Aconselhamento Diretivo/estatística & dados numéricos , Relações Médico-Paciente , Feminino , Seguimentos , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Estados Unidos/epidemiologia
13.
Osteoarthritis Cartilage ; 25(6): 976-985, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28011101

RESUMO

OBJECTIVE: Chronic kidney disease (CKD) is characterized by metabolic disturbances in calcium and phosphorus homeostasis as kidney function declines. Alterations in blood perfusion in bone resulting from arteriosclerosis of bone vessels may relate to the progression of CKD. Herein, change in dynamic contrast enhanced (DCE) MRI parameters (A: amplitude, kel: elimination constant, and kep: permeability rate constant) and MRI T2∗ relaxation time of the knee cartilage were measured in a rodent nephrectomy model in order to (1) examine the relationship of peripheral blood perfusion to CKD and (2) demonstrate the feasibility of using DCE-MRI parameters and MRI T2∗ as imaging biomarkers to monitor disease progression. DESIGN: Two groups of male Sprague-Dawley rats received either (1) no intervention or (2) 5/6 nephrectomy. RESULTS: We found that the CKD group (compared with the control group) had lower A and kel values and similar kep value in the lateral and medial articular cartilages beginning at 12 weeks (P < 0.05); statistically significantly higher T2∗ values in the lateral and medial articular cartilages beginning at 18 weeks (P < 0.05); statistically significantly decreased inner luminal diameter of the popliteal artery, and altered structure of the lateral and medial articular cartilages (P < 0.05). CONCLUSION: Perfusion deficiency and CKD may be related. DCE parameters and MRI T2∗ could serve as imaging biomarkers of cartilage degeneration in CKD progression.


Assuntos
Cartilagem Articular/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Fluxo Sanguíneo Regional , Insuficiência Renal Crônica/diagnóstico por imagem , Animais , Cartilagem Articular/irrigação sanguínea , Modelos Animais de Doenças , Articulação do Joelho/irrigação sanguínea , Imageamento por Ressonância Magnética , Masculino , Nefrectomia , Ratos , Ratos Sprague-Dawley
14.
J Evol Biol ; 30(5): 951-959, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28235138

RESUMO

Reproductive success is associated with age in many taxa, increasing in early life followed by reproductive senescence. In socially monogamous but genetically polygamous species, this generates the interesting possibility of differential trajectories of within-pair and extra-pair siring success with age in males. We investigate these relationships simultaneously using within-individual analyses with 13 years of data from an insular house sparrow (Passer domesticus) population. As expected, we found that both within- and extra-pair paternity success increased with age, followed by a senescence-like decline. However, the age trajectories of within- and extra-pair paternity successes differed significantly, with the extra-pair paternity success increasing faster, although not significantly, in early life, and showing a delayed decline by 1.5 years on average later in life compared to within-pair paternity success. These different trajectories indicate that the two alternative mating tactics should have age-dependent pay-offs. Males may partition their reproductive effort between within- and extra-pair matings depending on their current age to reap the maximal combined benefit from both strategies. The interplay between these mating strategies and age-specific mortality may explain the variation in rates of extra-pair paternity observed within and between species.


Assuntos
Paternidade , Comportamento Sexual Animal , Pardais , Animais , Masculino , Reprodução
15.
Acta Anaesthesiol Scand ; 61(9): 1166-1175, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28832898

RESUMO

BACKGROUND: The study objective was to examine the correlation between regional ventilation distribution measured with electrical impedance tomography (EIT) and weaning outcomes during spontaneous breathing trial (SBT). METHODS: Fifteen patients received 100% automatic tube compensation (ATC) during the first and 70% during the second hour. Another 15 patients received external continuous positive airway pressure (CPAP) of 5 and 7.5 cmH2 O during the first and second hours, respectively. Regional ventilation distributions were monitored with EIT. RESULTS: Tidal volume and tidal variation of impedance correlated significantly during assist-control ventilation and ATC in all patients (r2 = 0.80 ± 0.18, P < 0.001). Higher support levels resulted in similar ventilation distribution and tidal volume, but higher end-expiratory lung impedance (EELI) (P < 0.05). Analysis of regional intratidal gas distribution revealed a redistribution of ventilation towards dorsal regions with lower support level in 13 of 30 patients. These patients had a higher weaning success rate (only 1 of 13 patients failed). Eight of 17 other patient failed (P < 0.05). The number of SBT days needed for weaning was significantly lower in the former group of 13 patients (13.1 ± 4.0 vs. 20.9 ± 11.2 days, P < 0.05). CONCLUSIONS: Regional ventilation distribution patterns during inspiration were associated with weaning outcomes, and they may be used to predict the success of extubation.


Assuntos
Respiração Artificial/métodos , Respiração , Idoso , Idoso de 80 Anos ou mais , Extubação , Algoritmos , Pressão Positiva Contínua nas Vias Aéreas , Impedância Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Volume de Ventilação Pulmonar , Tomografia , Desmame do Respirador
17.
Ann Oncol ; 27(12): 2196-2203, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27765757

RESUMO

BACKGROUND: We report the first randomized, Phase II trial of ramucirumab, an anti-vascular endothelial growth factor receptor-2 monoclonal antibody, as front-line therapy in patients with advanced adenocarcinoma of the esophagus or gastric/gastroesophageal junction (GEJ). PATIENTS AND METHODS: Patients from the USA with advanced esophageal, gastric, or GEJ adenocarcinoma randomly received (1:1) mFOLFOX6 plus ramucirumab (8 mg/kg) or mFOLFOX6 plus placebo every 2 weeks. The primary end point was progression-free survival (PFS) with 80% power to detect a hazard ratio (HR) of 0.71 (one-sided α = 0.15). Secondary end points included evaluation of response and overall survival (OS); an exploratory ramucirumab exposure-response analysis was undertaken. RESULTS: Of 168 randomized patients, 52% of tumors were located in the stomach/GEJ and 48% in the esophagus. The trial did not meet the primary end point of PFS [6.4 versus 6.7 months, HR 0.98 (95% confidence interval 0.69-1.37)] or the secondary end point of OS (11.7 versus 11.5 months) in the intent-to-treat (ITT) population. Objective response rates (45.2% versus 46.4%) were similar between arms. Most Grade ≥3 toxicities did not differ significantly between arms, yet premature discontinuation of FOLFOX and ramucirumab (for reasons other than progressive disease) was more common among ramucirumab- versus placebo-treated patients. In an exploratory analysis that censored for premature discontinuation, the HR for PFS favored the ramucirumab arm (HR 0.76), particularly in patients with gastric/GEJ cancer. An exploratory exposure-response analysis indicated that patients with higher ramucirumab exposure had longer OS. CONCLUSION: The addition of ramucirumab to front-line mFOLFOX6 did not improve PFS in the ITT population. CLINICALTRIALSGOV IDENTIFIER: NCT01246960.


Assuntos
Adenocarcinoma/tratamento farmacológico , Anticorpos Monoclonais/administração & dosagem , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/patologia , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Intervalo Livre de Doença , Método Duplo-Cego , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/efeitos dos fármacos , Feminino , Fluoruracila/administração & dosagem , Humanos , Estimativa de Kaplan-Meier , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Resultado do Tratamento , Ramucirumab
18.
Osteoarthritis Cartilage ; 24(1): 129-33, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26241778

RESUMO

OBJECTIVE: Although anterior cruciate ligament (ACL) injury is a well-recognized risk factor for developing knee post-traumatic osteoarthritis (PTOA), the process in the patellofemoral (PF) joint after ACL injury is still under-researched. Our aim was to investigate the perfusion changes in PF subchondral bone marrow in the rat ACL transection (ACLX) model of PTOA using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). DESIGN: Eighteen male Sprague Dawley rats were randomly separated into three groups (n = 6 each group): a normal control group and groups receiving ACLX and sham-surgery, respectively, in the right knee. Perfusion parameters in the patellar and femoral subchondral bone marrows of all rats were measured on DCE-MRI at 0, 4, 8, and 16 weeks after respective treatment. After the last MRI at week 16, the rats were sacrificed and their right knees were harvested for histologic examination. In addition, to observe the long-term histologic change in PF joints, 9 additional rats (n = 3 in each group) were included and sacrificed at week 32 for histologic examination. RESULTS: In the ACLX group vs the sham and control groups, the perfusion parameters were significantly changed in both patellar and femoral subchondral bone marrows at week 16. Histologic examination revealed cartilage defects in ACLX rats at 32 weeks after surgery. CONCLUSIONS: These data point to a possible functional relationship between subchondral bone marrow perfusion abnormalities and cartilage breakdown in PTOA. Moreover, the perfusion parameters derived from DCE-MRI can potentially serve as biomarkers of early OA.


Assuntos
Lesões do Ligamento Cruzado Anterior , Medula Óssea/irrigação sanguínea , Fêmur/irrigação sanguínea , Osteoartrite do Joelho/fisiopatologia , Patela/irrigação sanguínea , Animais , Meios de Contraste , Traumatismos do Joelho/complicações , Imageamento por Ressonância Magnética , Masculino , Osteoartrite do Joelho/etiologia , Ratos , Ratos Sprague-Dawley
19.
Mol Psychiatry ; 20(7): 850-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25824299

RESUMO

Abnormal activity in the medial prefrontal cortex (mPFC) is consistently observed in neuropsychiatric disorders, but the mechanisms involved remain unclear. Chronic aberrant excitation and/or inhibition of mPFC neurons were proposed to cause cognitive impairments. However, direct evidence for this hypothesis is lacking because it is technically challenging to control synaptic properties in a chronic and locally restricted, yet specific, manner. Here, we generated conditional knockout (cKO) mice of neuroligin-2 (Nlgn2), a postsynaptic cell-adhesion molecule of inhibitory synapses linked to neuropsychiatric disorders. cKO of Nlgn2 in adult mPFC rendered Nlgn2 protein undetectable after already 2-3 weeks, but induced major reductions in synaptic inhibition after only 6-7 weeks, and caused parallel impairments in anxiety, fear memory and social interaction behaviors. Moreover, cKO of Nlgn2 severely impaired behavioral stimulation of immediate-early gene expression in the mPFC, suggesting that chronic reduction in synaptic inhibition uncoupled the mPFC from experience-dependent inputs. Our results indicate that Nlgn2 is required for continuous maintenance of inhibitory synapses in the adult mPFC, and that chronic impairment of local inhibition disengages the mPFC from its cognitive functions by partially uncoupling the mPFC from experience-induced inputs.


Assuntos
Moléculas de Adesão Celular Neuronais/genética , Moléculas de Adesão Celular Neuronais/fisiologia , Transtornos Cognitivos/fisiopatologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Inibição Neural/fisiologia , Córtex Pré-Frontal/fisiopatologia , Sinapses/fisiologia , Animais , Ansiedade/patologia , Ansiedade/fisiopatologia , Moléculas de Adesão Celular Neuronais/deficiência , Transtornos Cognitivos/patologia , Condicionamento Psicológico/fisiologia , Medo/fisiologia , Potenciais da Membrana/fisiologia , Memória/fisiologia , Camundongos Knockout , Proteínas do Tecido Nervoso/deficiência , Técnicas de Patch-Clamp , Córtex Pré-Frontal/patologia , Comportamento Social , Sinapses/patologia , Transmissão Sináptica/fisiologia , Técnicas de Cultura de Tecidos
20.
Diabetes Obes Metab ; 18(12): 1199-1206, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27407013

RESUMO

AIM: To evaluate the comparative effects of sodium-glucose co-transporter 2 (SGLT2) inhibitors on risk of bone fracture in patients with type 2 diabetes mellitus (T2DM). METHODS: PubMed, EMBASE, CENTRAL and ClinicalTrials.gov were systematically searched from inception to 27 January 2016 to identify randomized controlled trials (RCTs) reporting the outcome of fracture in patients with T2DM treated with SGLT2 inhibitors. Pairwise and network meta-analyses, as well as a cumulative meta-analysis, were performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: A total of 38 eligible RCTs (10 canagliflozin, 15 dapagliflozin and 13 empagliflozin) involving 30 384 patients, with follow-ups ranging from 24 to 160 weeks, were included. The fracture event rates were 1.59% in the SGLT2 inhibitor groups and 1.56% in the control groups. The incidence of fracture events was similar among these three SGLT2 inhibitor groups. Compared with placebo, canagliflozin (OR 1.15; 95% CI 0.71-1.88), dapagliflozin (OR 0.68; 95% CI 0.37-1.25) and empagliflozin (OR 0.93; 95% CI 0.74-1.18) were not significantly associated with an increased risk of fracture. Our cumulative meta-analysis indicated the robustness of the null findings with regard to SGLT2 inhibitors. CONCLUSIONS: Our meta-analysis based on available RCT data does not support the harmful effect of SGLT2 inhibitors on fractures, although future safety monitoring from RCTs and real-world data with detailed information on bone health is warranted.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Fraturas Ósseas/epidemiologia , Hipoglicemiantes/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose , Compostos Benzidrílicos/uso terapêutico , Canagliflozina/uso terapêutico , Glucosídeos/uso terapêutico , Humanos , Incidência , Metanálise em Rede , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco
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