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1.
Sensors (Basel) ; 24(12)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38931529

RESUMO

A design for a pogo-pin probe card featuring a metallic socket is proposed to eliminate signal leakage and coupling loss in a multi-port environment. The proposed metallic pogo-pin socket includes a metal wall structure between adjacent pogo pins, ensuring complete isolation. This metal wall offers an advantage in removing coupling issues between pogo pins that can occur with typical dielectric pogo-pin sockets. The designed probe card is fabricated as a prototype and verified for its performance. Measurement results using a test through line show that coupled power is minimized, providing a low-loss transmission performance of -2.14 dB to an RF chip at 50 GHz, all within a compact size. Although the dielectric spacer used to secure the pogo pins allows for some leakage, it can maintain a low coupling performance of under -15 dB in the millimeter-wave band. The prototype probe card can deliver an RF signal to a 5G circuit with a low loss of -0.7 dB at 28 GHz and -1.9 dB at 39 GHz frequency. The designed probe card is capable of transmitting multiple RF signals to the RF system without signal distortion in a multi-port environment.

2.
Sensors (Basel) ; 23(12)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37420587

RESUMO

A design for a millimeter wave RF probe card that removes resonance is proposed. The designed probe card optimizes the position of the ground surface and the signal pogo pins to resolve the resonance and signal loss issues that occur when connecting a dielectric socket and a PCB. At millimeter wave frequencies, the height of the dielectric socket and pogo pin matches the length of half a wavelength, allowing the socket to act as a resonator. When the leakage signal from the PCB line is coupled to the 2.9 mm high socket with pogo pins, resonance at a frequency of 28 GHz is generated. The probe card uses the ground plane as a shielding structure to minimize this resonance and radiation loss. The importance of the signal pin location is verified via measurements in order to address the discontinuity caused by field polarity switching. A probe card fabricated using the proposed technique exhibits an insertion loss performance of -8 dB up to 50 GHz and eliminates resonance. A signal with an insertion loss of -3.1 dB can be transmitted to a system-on-chip in a practical chip test.


Assuntos
Utensílios Domésticos , Fixadores Internos , Imagem de Difusão por Ressonância Magnética , Publicações , Registros
3.
Mol Psychiatry ; 25(2): 368-378, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31455859

RESUMO

Cellular models of neurodevelopmental disorders provide a valuable experimental system to uncover disease mechanisms and novel therapeutic strategies. The ability of induced pluripotent stem cells (iPSCs) to generate diverse brain cell types offers great potential to model several neurodevelopmental disorders. Further patient-derived iPSCs have the unique genetic and molecular signature of the affected individuals, which allows researchers to address limitations of transgenic behavioural models, as well as generate hypothesis-driven models to study disorder-relevant phenotypes at a cellular level. In this article, we review the extant literature that has used iPSC-based modelling to understand the neuronal and glial contributions to neurodevelopmental disorders including autism spectrum disorder (ASD), Rett syndrome, bipolar disorder (BP), and schizophrenia. For instance, several molecular candidates have been shown to influence cellular phenotypes in three-dimensional iPSC-based models of ASD patients. Delays in differentiation of astrocytes and morphological changes of neurons are associated with Rett syndrome. In the case of bipolar disorders and schizophrenia, patient-derived models helped to identify cellular phenotypes associated with neuronal deficits (e.g., excitability) and mutation-specific abnormalities in oligodendrocytes (e.g., CSPG4). Further we provide a critical review of the current limitations of this field and provide methodological suggestions to enhance future modelling efforts of neurodevelopmental disorders. Future developments in experimental design and methodology of disease modelling represent an exciting new avenue relevant to neurodevelopmental disorders.


Assuntos
Transtornos do Neurodesenvolvimento/metabolismo , Transtornos do Neurodesenvolvimento/fisiopatologia , Células-Tronco Pluripotentes/metabolismo , Astrócitos/metabolismo , Diferenciação Celular , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Modelos Biológicos , Neuroglia/metabolismo , Neurônios/metabolismo , Fenótipo
4.
BJOG ; 128(4): 738-744, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32946626

RESUMO

OBJECTIVE: To determine whether postpartum haemorrhage (PPH) is associated with cardiovascular disease (CVD), including cerebrovascular and ischaemic heart disease beyond the peripartum period. DESIGN: Population-based cohort study. SETTING: Merged databases of the Korea National Health Insurance (KNHI) claims, National Health Screening Examination and National Health Screening Program for Infants and Children. POPULATION: Women who gave birth in 2007 in the Republic of Korea and who were tracked through to 2015 for the occurrence of CVD. METHODS: Patients were identified and the occurrences of PPH and transfusion were determined using the KNHI claims database. The occurrence of CVD was tracked through 2015 using codes from the International Classification of Diseases, tenth revision (ICD-10). MAIN OUTCOME MEASURES: The risk of CVD after PPH. RESULTS: Among 150 381 women who gave birth during the study period, 9107 were diagnosed with PPH and 899 were treated with transfusion. The risk of CVD in women with PPH was no different than in women without PPH, after adjustment (HR 1.03, 95% CI 0.93-1.13). The risk of CVD in women with PPH requiring transfusion was significantly increased compared with women without PPH, after adjustment (HR 1.60, 95% CI 1.25-2.06). The risk of CVD in women with PPH without transfusion was not significantly different compared with women without PPH (HR 0.96, 95% CI 0.86-1.07). CONCLUSIONS: Postpartum haemorrhage (PPH) requiring transfusion is associated with an increased risk of CVD. Guidelines for management should be established, and further studies on the mechanisms involved should be conducted. TWEETABLE ABSTRACT: PPH requiring transfusion is associated with an increased risk of CVD.


Assuntos
Transfusão de Sangue , Doenças Cardiovasculares/etiologia , Hemorragia Pós-Parto/terapia , Adulto , Doenças Cardiovasculares/epidemiologia , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Incidência , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Gravidez , Modelos de Riscos Proporcionais , República da Coreia/epidemiologia , Estudos Retrospectivos , Fatores de Risco
5.
Osteoarthritis Cartilage ; 28(4): 486-491, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32028021

RESUMO

OBJECTIVES: Pharmacological options for treating osteoarthritis (OA) are limited and alternative treatments are required. Given the clinical data indicating that granulocyte macrophage-colony stimulating factor (GM-CSF) may be a therapeutic target in human OA, we evaluated different treatment regimens with a neutralizing anti-GM-CSF monoclonal antibody (mAb) in an experimental OA model to determine their effectiveness on amelioration of pain and disease. METHODS: The collagenase-induced osteoarthritis (CiOA) model was induced in C57BL/6 mice, followed by different treatment regimens of anti-GM-CSF mAb or isotype control. Anti-CCL17 mAb treatment was also administered continually during the late stage of CiOA. Pain-related behavior (change in weight distribution of hind limbs), and disease (cartilage damage and osteophyte size) were assessed. RESULTS: Blocking GM-CSF only during early synovitis in CiOA prevented pain and disease development. Once OA pain was established, regardless of the treatment regimen, anti-GM-CSF mAb treatment rapidly and efficiently ameliorated it; however, unless the treatment was continued, pain returned and disease progressed. Continual late stage blockade of GM-CSF was able to ameliorate pain (between-group difference: -6.567; 95% confidence interval (CI): -10.12, -3.011) and suppress cartilage damage (P = 0.0317, 95% CI: -1.75, -0.0556). Continual late stage blockade of CCL17 showed similar effects on pain and disease development. CONCLUSIONS: Early and short-term GM-CSF neutralization is effective at preventing CiOA pain and disease development but, once pain is evident, continual GM-CSF blockade is required to prevent pain from returning and to suppress disease progression in mice. These data reinforce the potential benefits of anti-GM-CSF (and anti-CCL17) mAb therapy in OA and should inform further clinical trials.


Assuntos
Anticorpos Neutralizantes/farmacologia , Cartilagem Articular/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Osteoartrite do Joelho/patologia , Joelho de Quadrúpedes/efeitos dos fármacos , Membrana Sinovial/efeitos dos fármacos , Animais , Artrite Experimental/induzido quimicamente , Artrite Experimental/patologia , Cartilagem Articular/patologia , Quimiocina CCL17/antagonistas & inibidores , Colagenases/toxicidade , Progressão da Doença , Intervenção Médica Precoce , Injeções Intra-Articulares , Camundongos , Osteoartrite do Joelho/induzido quimicamente , Osteófito/patologia , Medição da Dor , Joelho de Quadrúpedes/patologia , Membrana Sinovial/patologia , Sinovite/patologia
6.
Opt Express ; 27(12): 16571-16577, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31252881

RESUMO

We demonstrate the generation of spectrally tunable phase-dependent wavefronts, using the 2D Airy as the primary test case, via a polymer-stabilized cholesteric liquid crystal (PSCLC) element. Specifically, we use a novel spatial light modulator (SLM) based projection system to photo-align the initial helix angle landscape of the PSCLC so that it imparts the appropriate cubic phase profile to the reflected beam. This element is spectrally selective, with a reflection bandwidth of ≈ 100 nm, and electrically tunable from λ = 530 nm to 760 nm. Under both green and red laser illumination, the element is shown to conditionally form an Airy beam depending on the position of the electrically tailored reflection band. We briefly demonstrate the generality of this approach by producing PSCLC elements which form a computer-generated hologram and a higher-order Mathieu beam.

7.
Lupus ; 28(7): 898-902, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31042127

RESUMO

Headaches are common in patients with systemic lupus erythematosus (SLE). It is important to identify the exact cause of headaches in SLE to avoid unnecessary steroid or immunosuppressive therapy like in neuropsychiatric SLE. A 35-year-old woman with SLE suddenly developed severe headache. Magnetic resonance angiography showed multifocal segmental narrowing of cerebral arteries, suggestive of central nervous system vasculitis. However, lack of abnormal enhancement in vessel wall imaging indicated reversible cerebral vasoconstriction syndrome (RCVS) rather than central nervous system vasculitis. The patient was treated with oral nimodipine and she recovered over a period of two months. Following magnetic resonance angiography on day 90 was normal. Herein we report a case of reversible cerebral vasoconstriction syndrome in an SLE patient with literature review.


Assuntos
Transtornos da Cefaleia Primários/etiologia , Vasculite Associada ao Lúpus do Sistema Nervoso Central/complicações , Vasoconstrição , Vasoespasmo Intracraniano/complicações , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/patologia , Diagnóstico Diferencial , Feminino , Humanos , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico por imagem , Angiografia por Ressonância Magnética , Síndrome , Vasoespasmo Intracraniano/diagnóstico por imagem
8.
BJOG ; 126(7): 901-905, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30758126

RESUMO

OBJECTIVES: To evaluate the association of a history of threatened preterm labour (TPL) followed by term delivery with the risk of spontaneous preterm delivery (PTD) in subsequent pregnancy. DESIGN: Population-based cohort study. SETTING: Data of the National Health Insurance Claims Database and a national health-screening programme for infants and children in South Korea. POPULATION: Women who had their first singleton delivery in 2010 and a subsequent second singleton delivery between 2011 and 2015. METHODS: Multivariable analysis adjusting for maternal age and interval between first and second deliveries was used to assess the risk of PTD based on PTD, TPL followed by term delivery, and term delivery in the first pregnancy. MAIN OUTCOME MEASURES: The risk of PTD during the second pregnancy. RESULTS: This study included 115 629 women with two consecutive deliveries during the study period. Spontaneous PTD rates in the second pregnancy were 7.71, 2.22 and 1.02% in women with PTD, TPL followed by term delivery, and term delivery in the first pregnancy, respectively. Threatened preterm labour followed by term delivery in the first pregnancy was associated with increased risk of PTD in the subsequent pregnancy after adjustment for potential confounding factors (adjusted odds ratio 2.21; 95% CI 1.76-2.78). CONCLUSION: Although women with a history of TPL followed by term delivery had a lower risk of PTD during a subsequent pregnancy compared with those with history of previous PTD, they still had a significantly increased risk of PTD compared with those who delivered at term without TPL. TWEETABLE ABSTRACT: The history of threatened preterm labour followed by term delivery is related to increased risk of subsequent spontaneous preterm delivery.


Assuntos
Ameaça de Aborto/epidemiologia , Nascimento Prematuro/epidemiologia , Nascimento a Termo/fisiologia , Adulto , Estudos de Coortes , Feminino , Humanos , Idade Materna , Gravidez , Recidiva , República da Coreia/epidemiologia , Fatores de Risco
9.
Neuropathol Appl Neurobiol ; 44(6): 590-605, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29380402

RESUMO

AIMS: Degeneration of the distal neuromuscular circuitry is a hallmark pathology of Amyotrophic Lateral Sclerosis (ALS). The potential for microtubule dysfunction to be a critical pathophysiological mechanism in the destruction of this circuitry is increasingly being appreciated. Stabilization of microtubules to improve neuronal integrity and pathology has been shown to be a particularly favourable approach in other neurodegenerative diseases. We present evidence here that treatment with the microtubule-targeting compound Epothilone D (EpoD) both positively and negatively affects the spinal neuromuscular circuitry in the SOD1G93A mouse model of ALS. METHODS: SOD1G93A mice were treated every 5 days with 2 mg/kg EpoD. Evaluation of motor behaviour, neurological phenotype and survival was completed, with age-dependent histological characterization also conducted, using the thy1-YFP mouse. Motor neuron degeneration, axonal integrity, neuromuscular junction (NMJ) health and gliosis were also assessed. RESULTS: EpoD treatment prevented loss of the spinal motor neuron soma, and distal axon degeneration, early in the disease course. This, however, was not associated with protection of the NMJ synapse and did not improve motor phenotype or clinical progression. EpoD administration was also found to be neurotoxic at later disease stages. This was evidenced by accelerated motor neuron cell body loss, increasing gliosis, and was associated with detrimental outcomes to motor behaviour, clinical assessment and survival. CONCLUSIONS: The results suggest that EpoD accelerates disease progression in the SOD1G93A mouse model of ALS, and highlights that the pathophysiological involvement of microtubules in ALS is an evolving and underappreciated phenomenon.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Epotilonas/farmacologia , Neurônios Motores/patologia , Junção Neuromuscular/patologia , Superóxido Dismutase-1/genética , Esclerose Lateral Amiotrófica/genética , Animais , Axônios/patologia , Modelos Animais de Doenças , Progressão da Doença , Força da Mão , Masculino , Camundongos , Camundongos Transgênicos , Neurônios Motores/efeitos dos fármacos , Destreza Motora/efeitos dos fármacos
10.
J Intellect Disabil Res ; 62(12): 1008-1017, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30450801

RESUMO

BACKGROUND: Self-injurious behaviour (SIB) can be classified as intentional, direct injuring of body tissue usually without suicidal intent. In its non-suicidal form it is commonly seen as a clinical sign of borderline personality disorder, autism, PTSD, depression, and anxiety affecting a wide range of ages and conditions. In rhesus macaques SIB is most commonly manifested through hair plucking, self-biting, self-hitting, and head banging. SIB in the form of self-biting is observed in approximately 5-15% of individually housed monkeys. Recently, glial cells are becoming recognised as key players in regulating behaviours. METHOD: The goal of this study was to determine the role of glial activation, including astrocytes, in macaques that had displayed SIB. To this end, we performed immunohistochemistry and next generation sequence of brain tissues from rhesus macaques with SIB. RESULTS: Our studies showed increased vimentin, but not nestin, expression on astrocytes of macaques displaying SIB. Initial RNA Seq analyses indicate activation of pathways involved in tissue remodelling, neuroinflammation and cAMP signalling. CONCLUSIONS: Glia are most probably activated in primates with self-injury, and are therefore potential novel targets for therapeutics.


Assuntos
Encéfalo/patologia , Neuroglia/patologia , Comportamento Autodestrutivo/patologia , Animais , Comportamento Animal , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Imuno-Histoquímica , Macaca mulatta , Comportamento Autodestrutivo/fisiopatologia
11.
Int Nurs Rev ; 65(2): 254-261, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28542894

RESUMO

AIM: To investigate the risk factors and predictors of falls according to the general characteristics, conscious state, physical condition and treatment of hospitalized patients with cancer. BACKGROUND: Inpatients with cancer experience falls more frequently than those without cancer, and the degree of injuries is more severe among inpatients with cancer. A specific fall prevention strategy is needed for each patient. Prevention of falls in patients with cancer is very important for improving the quality of nursing care. METHODS: This retrospective study included matched case-control patients. We evaluated patients between January 1, 2013, and December 31, 2014. A total of 356 patients (fall group, 178; non-fall group, 178) were included. For fall prediction, logistic regression was performed on the variables that were statistically significant in the univariate analysis. RESULTS: The variables that were significant predictors of falls were the use of an assistive device, history of falls and fatigue. DISCUSSION: The predictors of falls in patients with cancer include physical conditions and general characteristics. Fall prevention strategies in patients with cancer should be planned individually with multifaceted aspects, including physical symptom management. LIMITATIONS: The study was conducted at a single cancer center in Korea; thus, our results cannot be generalized. Additionally, in Korea, it is common to have family members or private caregivers for patient care, and this might have influenced the results. CONCLUSION AND IMPLICATIONS FOR NURSING AND HEALTH POLICY: The predictive factors for falls reflect the nature of the patient's environment, culture and disease. Falls have a negative effect on patient safety and can significantly influence quality of life. Policies for patient safety need more specialized and customized approaches.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Marcha/fisiologia , Neoplasias/complicações , Qualidade de Vida , Medição de Risco , Acidentes por Quedas/prevenção & controle , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Masculino , Neoplasias/terapia , República da Coreia , Estudos Retrospectivos , Fatores de Risco
12.
Am J Transplant ; 17(6): 1656-1662, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28296255

RESUMO

Immunologic tolerance to solid organ and islet cell grafts has been achieved in various rodent models by using antibodies directed at CD45RB and Tim-1. We have shown that this form of tolerance depends on regulatory B cells (Bregs). To elucidate further the mechanism by which Bregs induce tolerance, we investigated the requirement of natural killer (NK) and NKT cells in this model. To do so, hyperglycemic B6, µMT, Beige, or CD1d-/- mice received BALB/c islet grafts and treatment with the tolerance-inducing regimen consisting of anti-CD45RB and anti-TIM1. B6 mice depleted of both NK and NKT cells by anti-NK1.1 antibody and mice deficient in NK activity (Beige) did not develop tolerance after dual-antibody treatment. In contrast, transplant tolerance induction was successful in CD1d-/- recipients (deficient in NKT cells), indicating that NK, but not NKT, cells are essential in B cell-dependent tolerance. In addition, reconstitution of Beige host with NK cells restored the ability to induce transplant tolerance with dual-antibody treatment. Transfer of tolerance by B cells from tolerant mice was also dependent on host Nk1.1+ cells. In conclusion, these results show that regulatory function of B cells is dependent on NK cells in this model of transplantation tolerance.


Assuntos
Linfócitos B Reguladores/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Células Matadoras Naturais/imunologia , Células T Matadoras Naturais/imunologia , Tolerância ao Transplante/imunologia , Animais , Anticorpos Monoclonais/imunologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
14.
Osteoarthritis Cartilage ; 24(12): 2153-2161, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27421775

RESUMO

OBJECTIVE: SIRT1 has anti-inflammatory as well as protective effects in chondrocytes. The object of this study was to investigate whether microRNA-449a regulates expression of SIRT1, which inhibits expression of catabolic genes in IL-1ß-induced cartilage destruction. MATERIALS AND METHODS: MicroRNA-449a expression was determined in OA chondrocytes and IL-1ß-induced chondrocytes by real-time PCR. MicroRNA-449a binding sites on the 3'-UTR of SIRT1 mRNA and binding site conservation were examined using microRNA target prediction tools. SIRT1-overexpressing or knockdown chondrocytes were transfected with microRNA-449a or anti-microRNA-449a mimic and stimulated by IL-1ß. Expression of catabolic and anabolic genes was examined by real-time PCR and western blotting. Finally, positive effects of anti-microRNA-449a on expression of these genes were confirmed by western analysis of OA chondrocytes. RESULTS: Expression of microRNA-449a was increased in OA chondrocytes and IL-1ß-induced chondrocytes. MMP-13 expression was enhanced, whereas type II collagen and SIRT1 expression were decreased in IL-1ß-induced chondrocytes. SIRT1 overexpression resulted in decreased expression of catabolic genes such as MMPs and ADAMTSs in response to IL-1ß, but these effects were moderated by microRNA-449a. Suppression of microRNA-449a by anti-microRNA-449a inhibited expression of catabolic genes despite IL-1ß stimulation, but these effects were abolished in SIRT1 knockdown chondrocytes. Furthermore, expression of catabolic genes was decreased and expression of type II collagen as well as SIRT1 was restored by anti-microRNA-449a in OA chondrocytes as well as in IL-1ß-induced chondrocytes. CONCLUSION: Silencing of microRNA-449a had a protective effect, inhibiting catabolic gene expression and restoring anabolic gene expression, by targeting SIRT1 in IL-1ß-induced cartilage destruction.


Assuntos
Cartilagem , Células Cultivadas , Condrócitos , Humanos , Interleucina-1beta , MicroRNAs
15.
Osteoporos Int ; 27(8): 2477-88, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27010646

RESUMO

UNLABELLED: Vitamin D deficiency and insufficiency are highly prevalent among adolescents in Hong Kong, which is a sub-tropical city with ample sunshine. Vitamin D level is significantly correlated with key bone density and bone quality parameters. Further interventional studies are warranted to define the role of vitamin D supplementation for improvement of bone health among adolescents. INTRODUCTION: The relationship between bone quality parameters and vitamin D (Vit-D) status remains undefined among adolescents. The aims of this study were to evaluate Vit-D status and its association with both bone density and bone quality parameters among adolescents. METHODS: Three hundred thirty-three girls and 230 boys (12-16 years old) with normal health were recruited in summer and winter separately from local schools. Serum 25(OH) Vit-D level, bone density and quality parameters by Dual Energy X-ray Absorptiometry (DXA) and High-Resolution peripheral Quantitative Computed Tomography (HR-pQCT), dietary calcium intake, and physical activity level were assessed. RESULTS: Sixty-four point seven percent and 11.4 % of subjects were insufficient [25 ≤ 25(OH)Vit-D ≤ 50 nmol/L] and deficient [25(OH)Vit-D < 25 nmol/L] in Vit-D, respectively. The mean level of serum 25(OH)Vit-D in summer was significantly higher than that in winter (44.7 ± 13.6 and 35.9 ± 12.6 nmol/L, respectively) without obvious gender difference. In girls, areal bone mineral density (aBMD) and bone mineral content (BMC) of bilateral femoral necks, cortical area, cortical thickness, total volumetric bone mineral density (vBMD), and trabecular thickness were significantly correlated with 25(OH)Vit-D levels. In boys, aBMD of bilateral femoral necks, BMC of the dominant femoral neck, cortical area, cortical thickness, total vBMD, trabecular vBMD, BV/TV, and trabecular separation were significantly correlated with 25(OH)Vit-D levels. CONCLUSION: Vit-D insufficiency was highly prevalent among adolescents in Hong Kong with significant correlation between Vit-D levels and key bone density and bone quality parameters being detected in this study. Given that this is a cross-sectional study and causality relationship cannot be inferred, further interventional studies investigating the role of Vit-D supplementation on improving bone health among adolescents are warranted.


Assuntos
Densidade Óssea , Deficiência de Vitamina D/epidemiologia , Vitamina D/análogos & derivados , Absorciometria de Fóton , Adolescente , Criança , Estudos Transversais , Feminino , Colo do Fêmur/diagnóstico por imagem , Hong Kong , Humanos , Masculino , Prevalência , Estações do Ano , Tomografia Computadorizada por Raios X , Vitamina D/sangue , Deficiência de Vitamina D/diagnóstico por imagem
16.
Int J Sports Med ; 37(13): 1080-1086, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27676145

RESUMO

This study aimed to investigate the relationship between bone morphology and injured ligaments on imaging studies and laxity on ankle stress radiographs in patients with lateral ankle instability. In total, 115 patients who had undergone ankle MRI, ankle radiography, and stress radiography were included. Distal tibial articular surface angle, bimalleolar tilt, medial and lateral malleolar relative length, medial malleolar slip angle, anterior inclination of the tibia, and fibular position were measured on ankle radiographs. Tibiotalar tilt angle and anterior translation of the talus were measured on ankle stress radiographs. Degree of ligament injury was evaluated on ankle MRIs. Multiple regression analysis was performed using the following independent variables: age, sex, and factors significantly associated with ankle stress view on univariate linear regression analysis. Age (p=0.041), sex (p=0.014), degree of anterior talofibular ligament injury (p<0.001), and bimalleolar tilt (p=0.016) were correlated with tibiotalar tilt angle. Fibular position and degree of posterior talofibular ligament injury were factors significantly related to anterior translation of the talus. Differences in patient characteristics might predispose ankle stress radiograph results. Comparison of both ankles on stress radiographs is superior to applying fixed numerical values to the injured side in order to reduce the influence of patient factors.


Assuntos
Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/fisiopatologia , Instabilidade Articular , Ligamentos Laterais do Tornozelo/lesões , Tíbia/anatomia & histologia , Adulto , Idoso , Feminino , Fíbula/anatomia & histologia , Fíbula/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Tálus/anatomia & histologia , Tálus/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Adulto Jovem
17.
Int J Cosmet Sci ; 38(6): 622-626, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27139194

RESUMO

OBJECTIVE: Melanin is a black or brown phenolic polymer present mainly in skin and hair. Although melanin can be degraded by some microbial species, the melanin degradation capacity of Geotrichum sp. is unknown. The aim of this study was to characterize a melanin biodegradation enzyme from Geotrichum sp. METHODS: In this study, we assessed the melanin degradation activity of Geotrichum sp. in comparison with the major melanin-degrading enzymes, manganese-dependent peroxidase (MnP), manganese-independent peroxidase, lignin peroxidase and laccase. Furthermore, the effect of several carbohydrates on melanin degradation by Geotrichum sp. was determined. The MnP enzyme was purified using ammonium sulphate precipitation and Sephadex G-200 column chromatography, and then the conditions for optimal enzymatic activity were determined by adjusting the pH, temperature and Tween-80 concentration. RESULTS: Compared with extracellular ligninolytic enzymes of Geotrichum sp., MnP had the highest ligninolytic enzyme activity; and the highest enzymatic activity was observed in the presence of glucose. The final purified MnP enzyme exhibited 6 U mL-1 activity and had a molecular weight of 54.2 kDa. The enzymatic activity was highest at pH 4.5 and 25-35°C in the absence of Tween-80. CONCLUSION: These results indicate the potential of MnP purified from Geotrichum sp. as a skin-lightening agent in the cosmetic industry.


Assuntos
Geotrichum/enzimologia , Melaninas/metabolismo , Peroxidases/metabolismo , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Humanos , Peroxidases/isolamento & purificação
18.
Am J Transplant ; 15(10): 2739-49, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26014796

RESUMO

The full potential of islet transplantation will only be realized through the development of tolerogenic regimens that obviate the need for maintenance immunosuppression. Here, we report an immunotherapy regimen that combines 1-ethyl-3-(3'-dimethylaminopropyl)-carbodiimide (ECDI)-treated donor lymphoid cell infusion (ECDI-DLI) with thymoglobulin, anti-interleukin-6 receptor antibody and rapamycin to achieve prolonged allogeneic islet graft survival in a nonhuman primate (NHP) model. Prolonged graft survival is associated with Treg expansion, donor-specific T cell hyporesponsiveness and a transient absence of donor-specific alloantibody production during the period of graft survival. This regimen shows promise for clinical translation.


Assuntos
Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/imunologia , Imunossupressores/uso terapêutico , Transplante das Ilhotas Pancreáticas/imunologia , Isoantígenos/imunologia , Transfusão de Linfócitos/métodos , Linfócitos T Reguladores/imunologia , Animais , Quimioterapia Combinada , Rejeição de Enxerto/imunologia , Projetos Piloto , Primatas
19.
Osteoarthritis Cartilage ; 23(2): 232-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25450843

RESUMO

OBJECTIVE: We sought to determine (1) whether change in the tibial plateau inclination (TPI) after high tibial osteotomy (HTO) is different from change in the knee joint line orientation (KJLO) relative to the ground; (2) whether, in varus knee OA patients before and after HTO, these radiographic measures are different from those in normal control; and (3) whether the postoperative values of the TPI and KJLO relative to the ground are associated with short term clinical outcome scores after HTO. DESIGN: Fifty patients who underwent HTO and 75 normal controls were assessed with four radiographic measures. We compared the measures before HTO with those after HTO and with those of the normal controls, then examined associations between the postoperative radiographic measures and clinical outcome scores 1-year after HTO. RESULTS: After HTO, TPI increased 9.0°, whereas KJLO relative to the ground only increased 4.1°, with a compensatory change of the ankle joint line orientation. However, the postoperative KJLO relative to the ground in the HTO group was significantly different from that of the normal controls (mean difference, 4.9°; P < 0.001). In the multiple regression analyses, the postoperative radiographic measures were not associated with outcome clinical scores 1 year after HTO. CONCLUSION: After HTO the relative KJLO changed significantly less than did the anatomical geometry of the proximal tibia. Although the KJLO after the HTO was still significantly different from that of normal knees, its value did not adversely affect clinical outcome scores 1 year after HTO.


Assuntos
Articulação do Tornozelo/anatomia & histologia , Articulação do Joelho/anatomia & histologia , Osteoartrite do Joelho/cirurgia , Osteotomia , Tíbia/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteotomia/métodos , Período Pós-Operatório
20.
Calcif Tissue Int ; 97(4): 343-52, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26100651

RESUMO

Previous studies found adolescent idiopathic scoliosis (AIS) is associated with low bone mineral density (BMD) and abnormal bone quality, whilst the association between AIS and their bone strength is unknown. From high-resolution peripheral quantitative computed tomography-generated images, bone mechanical properties can be evaluated with finite element analysis (FEA), and trabecular rod-plate configuration related to trabecular bone strength can be quantified by structure model index (SMI). This study aimed to compare trabecular configuration and bone mechanical properties between AIS and the controls. 95 AIS girls aged 12-14 years and 97 age- and gender-matched normal controls were recruited. Bilateral femoral necks and non-dominant distal radius were scanned by dual-energy X-ray absorptiometry for areal BMD and HR-pQCT for SMI and FEA, respectively. Subjects were further classified into osteopenic and non-osteopenic group based on their areal BMD. Bone mechanical properties (stiffness, failure load and apparent modulus) were calculated using FEA. Linear regression model was used for controlling age, physical activity and calcium intake. AIS was associated with lower failure load and apparent modulus after adjusting for age, whereas AIS was associated with lower apparent modulus after adjusting for all confounders. Osteopenic AIS was associated with more rod-like trabeculae when compared with non-osteopenic AIS, whereas no difference was detected between osteopenic and non-osteopenic controls. This might be the result of abnormal regulation and modulation of bone metabolism and bone modelling and remodelling in AIS which will warrant future studies with a longitudinal design to determine the significance of micro-architectural abnormalities in AIS.


Assuntos
Osso e Ossos/diagnóstico por imagem , Osso e Ossos/fisiopatologia , Escoliose/fisiopatologia , Absorciometria de Fóton , Adolescente , Fenômenos Biomecânicos , Densidade Óssea , Doenças Ósseas Metabólicas , Estudos de Casos e Controles , Criança , Feminino , Análise de Elementos Finitos , Humanos , Escoliose/diagnóstico por imagem
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