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1.
Nature ; 603(7902): 648-653, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35264798

RESUMO

Birds morph their wing shape to accomplish extraordinary manoeuvres1-4, which are governed by avian-specific equations of motion. Solving these equations requires information about a bird's aerodynamic and inertial characteristics5. Avian flight research to date has focused on resolving aerodynamic features, whereas inertial properties including centre of gravity and moment of inertia are seldom addressed. Here we use an analytical method to determine the inertial characteristics of 22 species across the full range of elbow and wrist flexion and extension. We find that wing morphing allows birds to substantially change their roll and yaw inertia but has a minimal effect on the position of the centre of gravity. With the addition of inertial characteristics, we derived a novel metric of pitch agility and estimated the static pitch stability, revealing that the agility and static margin ranges are reduced as body mass increases. These results provide quantitative evidence that evolution selects for both stable and unstable flight, in contrast to the prevailing narrative that birds are evolving away from stability6. This comprehensive analysis of avian inertial characteristics provides the key features required to establish a theoretical model of avian manoeuvrability.


Assuntos
Voo Animal , Asas de Animais , Animais , Fenômenos Biomecânicos , Aves , Modelos Biológicos , Movimento (Física)
2.
J Adv Nurs ; 80(3): 1018-1029, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37828729

RESUMO

AIM: To explain the process taken by Chinese family care partners of older adults in the Greater Toronto Area, Canada, to access health and social services in their communities. The research question was: What mechanisms and structures impact the agency of Chinese family care partners of older adults, in the process of assisting them to access health and social services? DESIGN: This qualitative study was informed by critical realism. METHODS: Chinese family care partners of older adults in the Greater Toronto Area, Canada, were interviewed from August 2020 to June 2021. Transcripts underwent thematic analysis. FINDINGS: Twenty-eight Chinese family care partners expressed a firm commitment to maintain caregiving conditions and to judiciously access health and social services. Their commitment was made up of three parts: (a) legislative and cultural norms of family, work, and society; (b) their perseverance to fill gaps with limited social and financial resources; (c) the quality of their relationship to, and illness trajectory of the older adults. The social structures created tension in how Chinese family care partners made decisions, negotiated resources, and ultimately monitored and coordinated timely access with older adults. CONCLUSION: Participants' commitment and perseverance were conceptualized as "grit," central to their agency to conform to legislative and cultural norms. Moreover, findings support grit's power to motivate and sustain family caregiving, in order for older adults to age in place as long as possible with finite resources. IMPLICATIONS FOR THE PROFESSION: This study highlights the importance of cultural awareness education for nurses, enabling continuity of care at a systems level and for a more resilient healthcare system. IMPACT: Family care partners' grit may be crucial for nurses to harness when together, they face limited access to culturally appropriate health and social services in a system grounded in values of equity and inclusion, as in Canada. REPORTING METHOD: When writing this manuscript, we adhered to relevant EQUATOR guidelines of the Consolidated Criteria for Reporting Qualitative Research (COREQ). PATIENT OR PUBLIC INVOLVEMENT AND ENGAGEMENT: No patient or public involvement.


Assuntos
Povo Asiático , Cuidadores , Acessibilidade aos Serviços de Saúde , Aceitação pelo Paciente de Cuidados de Saúde , Idoso , Humanos , Povo Asiático/psicologia , Canadá/epidemiologia , Cuidadores/psicologia , China/etnologia , Pesquisa Qualitativa , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Intenção , Ontário/epidemiologia , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos
3.
J Ment Health ; 33(3): 386-393, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38845178

RESUMO

BACKGROUND: Mental illnesses and mental health challenges have become increasingly pervasive among Chinese university students. However, the utilization rate of mental health services is low among students. AIMS: We aimed to explore Chinese university students' help-seeking behaviors to understand how they deal with mental health challenges and use the results to inform the development of effective mental health promotion initiatives. METHODS: In this study, we conducted 13 focus group interviews with students in six universities in Jinan, China, including 91 (62%) female students and 56 (38%) male students. We drew on the Theory of Planned Behaviors to guide our thematic analysis to gain a contextual understanding of participants' accounts on help-seeking. RESULTS: Our results have depicted the help-seeking patterns of Chinese university students and show that there are four major behaviors which are self-reliance, seeking support from peers and families, seeking professional support, and accessing virtual mental health care. CONCLUSION: Results from this study can be used to inform the development of mental health literacy programming for students in universities that share similar contexts, and the study has also opened up a new space for using qualitative approaches to study mental health needs and access to care in diverse populations.


Assuntos
Comportamento de Busca de Ajuda , Transtornos Mentais , Serviços de Saúde Mental , Estudantes , Humanos , Feminino , Masculino , Estudantes/psicologia , Universidades , Adulto Jovem , China , Transtornos Mentais/terapia , Transtornos Mentais/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Adulto , Grupos Focais , Saúde Mental , Adolescente
4.
Opt Lett ; 48(3): 607, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723543

RESUMO

We present a corrigendum to our Letter [Opt. Lett.35, 703 (2010)10.1364/OL.35.000703]. In the original Letter we inadvertently included in Fig. 2(a) a TEM micrograph corresponding to a different, but very similar, sample. This corrigendum replaces Fig. 2(a) with a correct version. Since the main results are rather based in optical absorption measurements, and their modeling by using the T-matrix method, this correction does not affect the results and conclusions of the original Letter.

5.
Exp Parasitol ; 255: 108632, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37832775

RESUMO

The problem of resistance to acaricides in ticks such as Rhipicephalus microplus and R. sanguineus has motivated the search for control alternatives, such as the use of extracts and secondary metabolites from plants. Plumbagin is a natural product present in plants such as Plumbago zeylanica L., Diospyros kaki, and D. anisandra, of which acaricidal activity has been reported. Therefore, the objective of this study was to evaluate in vitro the acaricidal efficacy of plumbagin on larvae of R. microplus and R. sanguineus resistant to conventional acaricides. Larvae from engorged female ticks, collected from naturally infested dairy cattle and domiciled dogs, in Yucatan, Mexico, were used. The larval packet test and the larval immersion test were performed to detect acaricide susceptibility. Both tick populations were detected as resistant to cypermethrin and amitraz. Then, the modified larval immersion test was used and plumbagin was evaluated at concentrations of 1%, 0.5%, 0.25%, and 0.125% (%w/v), obtaining a mortality of 100% in the four concentrations for both tick species. Subsequently, lower doses of plumbagin were evaluated at concentrations of 0.0625%, 0.03125%, 0.015625% and 0.0078125%, obtaining mortalities of 100 to 36.26% for R. microplus and 100%-5.33% for R. sanguineus. Using Probit analysis, lethal concentrations at 50% (LC50), 99% (LC99) and confidence intervals at 95% (CI95%) were calculated. R. microplus showed a LC50 of 0.011% (CI95%: 0.010-0.011) and LC99 of 0.019% (CI95%: 0.018-0.022). R. sanguineus presented a LC50 of 0.017% (CI95%: 0.015-0.018) and CL99 of 0.031% (CI95%: 0.027-0.036). It was concluded that plumbagin has high acaricidal efficacy against larvae of R. microplus and R. sanguineus resistant to amitraz and cypermethrin. R. microplus larvae were significantly more susceptible to LC50 and LC99 compared to R. sanguineus. This is the first report on the acaricidal efficacy of plumbagin on larvae of R. microplus and R. sanguineus resistant to conventional acaricides.


Assuntos
Acaricidas , Rhipicephalus sanguineus , Rhipicephalus , Bovinos , Animais , Cães , Acaricidas/farmacologia , Larva
6.
BMC Biol ; 20(1): 104, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35550087

RESUMO

BACKGROUND: Lifelong production of the many types of mature blood cells from less differentiated progenitors is a hierarchically ordered process that spans multiple cell divisions. The nature and timing of the molecular events required to integrate the environmental signals, transcription factor activity, epigenetic modifications, and changes in gene expression involved are thus complex and still poorly understood. To address this gap, we generated comprehensive reference epigenomes of 8 phenotypically defined subsets of normal human cord blood. RESULTS: We describe a striking contraction of H3K27me3 density in differentiated myelo-erythroid cells that resembles a punctate pattern previously ascribed to pluripotent embryonic stem cells. Phenotypically distinct progenitor cell types display a nearly identical repressive H3K27me3 signature characterized by large organized chromatin K27-modification domains that are retained by mature lymphoid cells but lost in terminally differentiated monocytes and erythroblasts. We demonstrate that inhibition of polycomb group members predicted to control large organized chromatin K27-modification domains influences lymphoid and myeloid fate decisions of primary neonatal hematopoietic progenitors in vitro. We further show that a majority of active enhancers appear in early progenitors, a subset of which are DNA hypermethylated and become hypomethylated and induced during terminal differentiation. CONCLUSION: Primitive human hematopoietic cells display a unique repressive H3K27me3 signature that is retained by mature lymphoid cells but is lost in monocytes and erythroblasts. Intervention data implicate that control of this chromatin state change is a requisite part of the process whereby normal human hematopoietic progenitor cells make lymphoid and myeloid fate decisions.


Assuntos
Histonas , Células-Tronco Pluripotentes , Diferenciação Celular , Cromatina/genética , Cromatina/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Histonas/genética , Humanos , Recém-Nascido , Células-Tronco Pluripotentes/metabolismo
7.
Hong Kong Med J ; 29(1): 31-38, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36810238

RESUMO

INTRODUCTION: We investigated the impact of coronavirus disease 2019 (COVID-19) social distancing measures on fracture incidence and fracture-related mortality, as well as associations with population mobility. METHODS: In total, 47 186 fractures were analysed across 43 public hospitals from 22 November 2016 to 26 March 2020. Considering the smartphone penetration of 91.5% in the study population, population mobility was quantified using Apple Inc's Mobility Trends Report, an index of internet location services usage volume. Fracture incidences were compared between the first 62 days of social distancing measures and corresponding preceding epochs. Primary outcomes were associations between fracture incidence and population mobility, quantified by incidence rate ratios (IRRs). Secondary outcomes included fracture-related mortality rate (death within 30 days of fracture) and associations between emergency orthopaedic healthcare demand and population mobility. RESULTS: Overall, 1748 fewer fractures than projected were observed during the first 62 days of COVID-19 social distancing (fracture incidence: 321.9 vs 459.1 per 100 000 person-years, P<0.001); the relative risk was 0.690, compared with mean incidences during the same period in the previous 3 years. Population mobility exhibited significant associations with fracture incidence (IRR=1.0055, P<0.001), fracture-related emergency department attendances (IRR=1.0076, P<0.001), hospital admissions (IRR=1.0054, P<0.001), and subsequent surgery (IRR=1.0041, P<0.001). Fracture-related mortality decreased from 4.70 (in prior years) to 3.22 deaths per 100 000 person-years during the COVID-19 social distancing period (P<0.001). CONCLUSION: Fracture incidence and fracture-related mortality decreased during the early days of the COVID-19 pandemic; they demonstrated significant temporal associations with daily population mobility, presumably as a collateral effect of social distancing measures.


Assuntos
COVID-19 , Humanos , Incidência , Pandemias , Estudos Epidemiológicos , Hospitalização
8.
Hong Kong Med J ; 29(1): 39-48, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36810239

RESUMO

INTRODUCTION: This study evaluated the arched bridge and vacuole signs, which constitute morphological patterns of lung sparing in coronavirus disease 2019 (COVID-19), then examined whether these signs could be used to differentiate COVID-19 pneumonia from influenza pneumonia or bacterial pneumonia. METHODS: In total, 187 patients were included: 66 patients with COVID-19 pneumonia, 50 patients with influenza pneumonia and positive computed tomography findings, and 71 patients with bacterial pneumonia and positive computed tomography findings. Images were independently reviewed by two radiologists. The incidences of the arched bridge sign and/or vacuole sign were compared among the COVID-19 pneumonia, influenza pneumonia, and bacterial pneumonia groups. RESULTS: The arched bridge sign was much more common among patients with COVID-19 pneumonia (42/66, 63.6%) than among patients with influenza pneumonia (4/50, 8.0%; P<0.001) or bacterial pneumonia (4/71, 5.6%; P<0.001). The vacuole sign was also much more common among patients with COVID-19 pneumonia (14/66, 21.2%) than among patients with influenza pneumonia (1/50, 2.0%; P=0.005) or bacterial pneumonia (1/71, 1.4%; P<0.001). The signs occurred together in 11 (16.7%) patients with COVID-19 pneumonia, but they did not occur together in patients with influenza pneumonia or bacterial pneumonia. The arched bridge and vacuole signs predicted COVID-19 pneumonia with respective specificities of 93.4% and 98.4%. CONCLUSION: The arched bridge and vacuole signs are much more common in patients with COVID-19 pneumonia and can help differentiate COVID-19 pneumonia from influenza and bacterial pneumonia.


Assuntos
COVID-19 , Influenza Humana , Pneumonia Bacteriana , Humanos , Vacúolos , SARS-CoV-2 , Estudos Retrospectivos , Pulmão , Tomografia Computadorizada por Raios X/métodos
9.
Hong Kong Med J ; 29(6): 489-497, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38111367

RESUMO

INTRODUCTION: Healthcare workers in intensive care units often experience moral distress, depression, and stress-related symptoms. These conditions can lower staff retention and influence the quality of patient care. This study aimed to evaluate the prevalence of moral distress and psychological status among healthcare workers in a newly established paediatric intensive care unit (PICU) in Hong Kong. METHODS: A cross-sectional questionnaire survey was conducted in the PICU of the Hong Kong Children's Hospital; healthcare workers (doctors, nurses and allied health professionals) were invited to participate. The Revised Moral Distress Scale (MDS-R) Paediatric Version and Depression Anxiety and Stress Scale-21 items were used to assess moral distress and psychological status, respectively. Demographic characteristics were examined in relation to moral distress, depression, anxiety, and stress scores to identify risk factors for poor psychological outcomes. Correlations of moral distress with depression, anxiety, and stress were examined. RESULTS: Forty-six healthcare workers completed the survey. The overall median MDS-R moral distress score was 71. Nurses had a significantly higher median moral distress score, compared with doctors and allied health professionals (102 vs 47 vs 20). Nurses also had the highest median anxiety and stress scores (11 and 20, respectively). Moral distress scores were correlated with depression (r=0.445; P=0.002) and anxiety scores (r=0.417; P<0.05). Healthcare workers intending to quit their jobs had significantly higher moral distress scores (P<0.05). CONCLUSION: Among PICU healthcare workers, nurses had the highest level of moral distress. Moral distress was associated with greater depression, anxiety, and intention to quit. Healthcare workers need support and a sustainable working environment to cope with moral distress.


Assuntos
Pessoal de Saúde , Unidades de Terapia Intensiva Pediátrica , Humanos , Criança , Estudos Transversais , Unidades de Terapia Intensiva , Assistência ao Paciente , Inquéritos e Questionários , Princípios Morais , Estresse Psicológico/epidemiologia , Estresse Psicológico/etiologia
10.
Ann Surg Oncol ; 29(1): 354-363, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34114181

RESUMO

BACKGROUND: Many studies show significantly improved survival after R0 resection compared with R1 resection in pancreatic adenocarcinoma (PAC); however, the effect of neoadjuvant chemoradiation (NACRT) on this association is unknown. OBJECTIVE: The aim of this study was to evaluate the prognostic significance of positive surgical margins (SMs) after NACRT compared with upfront surgery + adjuvant therapy in PAC. METHODS: All cases of surgically resected PAC at a single institution were reviewed from 1996 to 2014; patients treated with palliative intent, metastatic disease, and biliary/ampullary tumors were excluded. The primary endpoint was overall survival (OS). RESULTS: Overall, 300 patients were included; 134 patients received NACRT with concurrent 5-fluorouracil or gemcitabine followed by surgery, and 166 patients received upfront surgery (+ adjuvant chemotherapy in 72% of patients and RT in 65%); 31% of both groups had a positive SM (+SM). The median OS for patients with a +SM or negative SM (-SM) was 26.6 and 31.6 months, respectively for NACRT, and 12.0 and 24.5 months, respectively, for upfront surgery. OS was significantly improved with -SM compared with +SM in both groups (p = 0.006). When resection yielded +SM, NACRT patients had improved OS compared with upfront surgery patients (p < 0.001). On multivariable analysis, +SM in the upfront surgery group (hazard ratio [HR] 2.94, 95% confidence interval [CI] 2.04-4.24; p < 0.001) and older age (HR 1.01, 95% CI 1.00-1.03, per year; p = 0.007) predicted worse OS. +SM in the NACRT group was not associated with worse OS (HR 1.09, 95% CI 0.72-1.65; p = 0.70). CONCLUSION: Patients with a positive margin after NACRT and surgery had longer survival compared with patients with a positive margin after upfront surgery. NACRT should be strongly considered for patients at high risk of R1 resections.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Adenocarcinoma/terapia , Idoso , Humanos , Margens de Excisão , Terapia Neoadjuvante , Neoplasias Pancreáticas/terapia , Prognóstico
11.
Hong Kong Med J ; 28(4): 315-320, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-33750741

RESUMO

The novel coronavirus disease (COVID-19) may result in acute respiratory distress syndrome and respiratory failure, necessitating mechanical respiratory support. Healthcare professionals are exposed to a particularly high risk of contracting the virus while providing resuscitation and respiratory support, which may in turn result in grave consequences and even death. Although COVID-19 has been shown to cause milder disease in children, paediatricians and intensivists who provide care for children must be prepared to provide optimal respiratory support without putting themselves or other medical, nursing, and paramedical staff at undue risk. We propose an airway management approach that is especially relevant in the current COVID-19 pandemic and provides instructions for: (1) Elective intubation for respiratory failure; and (2) Emergency intubation during cardiopulmonary resuscitation. To minimise risk, intubation methods must be kept as straightforward as possible and should include the provision of appropriate personal protection and equipment to healthcare workers. We identify two key considerations: that bag-mask ventilation should be avoided if possible and that bacterial and viral filters should be placed in the respiratory circuit. Our novel approach provides a framework for airway management that could benefit paediatric critical care practitioners who provide care for any children with a novel viral illness, with a focus on infection prevention during high-risk airway management procedures.


Assuntos
COVID-19 , Insuficiência Respiratória , Manuseio das Vias Aéreas/métodos , Criança , Humanos , Pandemias/prevenção & controle , SARS-CoV-2
12.
Hong Kong Med J ; 28(6): 475-481, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35815480

RESUMO

INTRODUCTION: Kidney cancer, primarily renal cell carcinoma (RCC), ranks among the top 10 most common malignancies in the male population of Hong Kong. In 2019, members of two medical societies in Hong Kong formed an expert panel to establish a set of consensus statements for the management of metastatic RCC. On 22 June 2021, the same panel met to review recent evidence and reassess their positions regarding the management of advanced and metastatic RCC, with the aim of providing recommendations for physicians in Hong Kong. PARTICIPANTS: The panel included 12 experts (6 clinical oncologists and 6 urologists) who had extensive experience managing patients with RCC in Hong Kong. EVIDENCE: The panel reviewed randomised controlled trials, observational studies, systematic reviews/meta-analyses, and international clinical guidelines to address key clinical questions that were identified before the meeting. CONSENSUS PROCESS: In total, 15 key clinical questions were identified before the meeting, covering the surgical and systemic treatment of advanced or metastatic clear cell, sarcomatoid, and non-clear cell RCCs. At the meeting, the panellists voted on these questions, then discussed relevant evidence and practical considerations. CONCLUSIONS: The treatment landscape for advanced and metastatic RCC continues to evolve. More immune checkpoint inhibitor (ICI)-based combination regimens will be indicated for the treatment of metastatic clear cell RCC. There is increasing evidence concerning the benefit of adjuvant ICI treatment for resected advanced RCC. This article summarises recent evidence and expert insights regarding a series of key clinical questions about the management of advanced and metastatic RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Masculino , Carcinoma de Células Renais/terapia , Neoplasias Renais/terapia , Hong Kong/epidemiologia , Consenso , Sociedades Médicas
13.
Learn Mem ; 28(2): 53-71, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33452115

RESUMO

Discrimination of sensory signals is essential for an organism to form and retrieve memories of relevance in a given behavioral context. Sensory representations are modified dynamically by changes in behavioral state, facilitating context-dependent selection of behavior, through signals carried by noradrenergic input in mammals, or octopamine (OA) in insects. To understand the circuit mechanisms of this signaling, we characterized the function of two OA neurons, sVUM1 neurons, that originate in the subesophageal zone (SEZ) and target the input region of the memory center, the mushroom body (MB) calyx, in larval Drosophila We found that sVUM1 neurons target multiple neurons, including olfactory projection neurons (PNs), the inhibitory neuron APL, and a pair of extrinsic output neurons, but relatively few mushroom body intrinsic neurons, Kenyon cells. PN terminals carried the OA receptor Oamb, a Drosophila α1-adrenergic receptor ortholog. Using an odor discrimination learning paradigm, we showed that optogenetic activation of OA neurons compromised discrimination of similar odors but not learning ability. Our results suggest that sVUM1 neurons modify odor representations via multiple extrinsic inputs at the sensory input area to the MB olfactory learning circuit.


Assuntos
Comportamento Animal/fisiologia , Discriminação Psicológica/fisiologia , Larva/fisiologia , Aprendizagem/fisiologia , Corpos Pedunculados/fisiologia , Neurônios/fisiologia , Octopamina/metabolismo , Percepção Olfatória/fisiologia , Animais , Drosophila , Neurônios/metabolismo , Optogenética
14.
Proc Biol Sci ; 288(1957): 20210727, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34428970

RESUMO

A formidable challenge for global change biologists is to predict how natural populations will respond to the emergence of conditions not observed at present, termed novel climates. Popular approaches to predict population vulnerability are based on the expected degree of novelty relative to the amplitude of historical climate fluctuations experienced by a population. Here, we argue that predictions focused on amplitude may be inaccurate because they ignore the predictability of environmental fluctuations in driving patterns of evolution and responses to climate change. To address this disconnect, we review major findings of evolutionary theory demonstrating the conditions under which phenotypic plasticity is likely to evolve in natural populations, and how plasticity decreases population vulnerability to novel environments. We outline key criteria that experimental studies should aim for to effectively test theoretical predictions, while controlling for the degree of climate novelty. We show that such targeted tests of evolutionary theory are rare, with marine systems being overall underrepresented in this venture despite exhibiting unique opportunities to test theory. We conclude that with more robust experimental designs that manipulate both the amplitude and predictability of fluctuations, while controlling for the degree of novelty, we may better predict population vulnerability to climate change.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Mudança Climática
15.
J Autoimmun ; 122: 102675, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34098405

RESUMO

Β2-Glycoprotein I (ß2GPI) is an important anti-thrombotic protein and is the major auto-antigen in the antiphospholipid syndrome (APS). The clinical relevance of nitrosative stress in post translational modification of ß2GPI was examined.The effects of nitrated (n)ß2GPI on its anti-thrombotic properties and its plasma levels in primary and secondary APS were determined with appropriate clinical control groups. ß2-glycoprotein I was nitrated at tyrosines 218, 275 and 309. ß2-glycoprotein I binds to lipid peroxidation modified products through Domains IV and V. Nitrated ß2GPI loses this binding (p < 0.05) and had diminished activity in inhibiting platelet adhesion to vWF under high shear flow (p < 0.01). Levels of nß2GPI were increased in patients with primary APS compared to patients with either secondary APS (p < 0.05), autoimmune disease without APS (p < 0.05) or non-autoimmune patients with arterial thrombosis (p < 0.01) and healthy individuals (p < 0.05).In conclusion tyrosine nitration of plasma ß2GPI is demonstrated and has important implications with regards to the pathophysiology of platelet mediated thrombosis in APS. Elevated plasma levels of nß2GPI in primary APS may be a risk factor for thrombosis warranting further investigation.


Assuntos
Síndrome Antifosfolipídica/complicações , Trombose/imunologia , beta 2-Glicoproteína I/imunologia , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/imunologia , Estudos de Casos e Controles , Voluntários Saudáveis , Humanos , Peroxidação de Lipídeos , Nitratos/metabolismo , Agregação Plaquetária/imunologia , Processamento de Proteína Pós-Traducional/imunologia , Fatores de Risco , Trombose/sangue , beta 2-Glicoproteína I/sangue , beta 2-Glicoproteína I/metabolismo
16.
Br J Surg ; 108(5): 574-582, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34043778

RESUMO

BACKGROUND: Attempts to improve limb preservation for transplantation using ex vivo perfusion have yielded promising results. However, metabolic acidosis, aberrant perfusate biochemistry and significant perfusion-induced oedema are reported universally. Optimizing perfusion protocols is therefore essential for maintaining tissue health. METHODS: A randomized, two-stage open preclinical trial design was used to determine the optimal temperature and mean arterial pressure for machine perfusion. Conditions compared were: normothermic machine perfusion at 70 mmHg (NMP-70); subnormothermic perfusion (28°C) at 70 mmHg; subnormothermic (28°C) perfusion at 50 mmHg; and hypothermic perfusion (10°C) at 30 mmHg. Following this, a head-to-head experiment was undertaken comparing the optimal machine perfusion with static cold storage. Paired bilateral limbs (10 in total) were randomized to either 8 h of static cold storage, or 2 h of static cold storage and 6 h of optimal machine perfusion. Both groups of limbs were then reperfused on a circuit primed with matched blood from unrelated donors for 4 h without immunosuppression. RESULTS: NMP-70 resulted in less tissue injury and stable perfusion biochemistry. Assessing reperfusion outcomes, static cold storage resulted in acidosis with increased lactate and a worsening electrolyte profile, necessitating bolus infusions of bicarbonate to prevent graft loss. Conversely, NMP-70 was associated with haemodynamic and biochemical stability. Histologically, on reperfusion with allogeneic whole blood, limbs subjected to static cold storage exhibited multifocal ischaemic injury and increased inflammation, which was absent with NMP-70. Static cold storage also resulted in significant oedema compared with NMP-70. CONCLUSION: Normothermic perfusion resulted in superior graft preservation and less reperfusion injury compared with the current static cold storage protocol.


Assuntos
Aloenxertos Compostos , Perfusão/métodos , Temperatura , Animais , Pressão Sanguínea , Sobrevivência de Enxerto , Modelos Animais , Distribuição Aleatória , Traumatismo por Reperfusão/prevenção & controle , Manejo de Espécimes , Suínos
17.
Qual Life Res ; 30(9): 2521-2530, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33783675

RESUMO

PURPOSE: Sleep problems are prevalent among the general population and can cause various health problems, which may lead to decreased quality of life. However, little is known about nonrestorative sleep and its implications. This study aimed to examine the association between nonrestorative sleep and health-related quality of life (HRQL) in Chinese adults. METHODS: Data were collected through a cross-sectional study of 500 adults in Hong Kong (66.4% female, average age of 39 years). The Short-Form-12 Health Survey version 2 (SF-12v2), Nonrestorative Sleep Scale (NRSS), Pittsburgh Sleep Quality Index, ENRICHD Social Support Instrument, Patient Health Questionnaire, Perceived Stress Scale, and Hospital Anxiety and Depression Scale were administered. Objective sleep parameters were based on participants' sleep condition over 1 week, as measured using an ActiGraph GT9X Link. RESULTS: Mean standardized scores for the physical component summary (PCS) and mental component summary (MCS) of the SF-12v2 and the NRSS were 50.33 ± 6.50, 49.00 ± 9.03, and 64.77 ± 12.75, respectively. After adjusting for sociodemographic and lifestyle characteristics, sleep quality, objective sleep parameters, social support, somatic symptoms, stress, anxiety, and depression, NRSS scores were associated with PCS (b = 0.12, 95%CI: 0.06 to 0.18, p < 0.001) and MCS (b = 0.08, 95%CI: 0.02 to 0.15, p = 0.013) scores. Furthermore, associations of NRSS score with PCS as well as MCS scores were stronger in women than in men. CONCLUSION: Nonrestorative sleep is a potentially modifiable risk factor for poor HRQL. Thus, interventions to relieve or decrease nonrestorative sleep could be beneficial for improving HRQL.


Assuntos
Qualidade de Vida , Transtornos do Sono-Vigília , Adulto , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Qualidade de Vida/psicologia , Sono , Transtornos do Sono-Vigília/epidemiologia , Inquéritos e Questionários
18.
BMC Nephrol ; 22(1): 291, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34445981

RESUMO

BACKGROUND: Percutaneous kidney biopsy is the gold standard investigation for the diagnosis of kidney diseases. The associated risks of the procedure depend on the skill and experience of the proceduralist as well as the characteristics of the patient. The Kidney Health Australia - Caring for Australasians with Renal Impairment (KHA-CARI) guidelines on kidney biopsies, published in 2019, are the only published national kidney biopsy guidelines. As such, this study surveys current kidney biopsy practices in Australasia and examines how they align with the Australian guidelines, as well as international biopsy practice. METHODS: A cross-sectional, multiple-choice questionnaire was developed examining precautions prior to kidney biopsy; rationalisation of medications prior to kidney biopsy; technical aspects of kidney biopsy; complications of kidney biopsy; and indications for kidney biopsy. This was distributed to all members of the Australian and New Zealand Society of Nephrology (ANZSN). RESULTS: The response rate for this survey is approximately 21.4 % (182/850). Respondents found agreement (> 75.0 %) in only six out of the twelve questions (50.0 %) which assessed their practice against the KHA-CARI guidelines. CONCLUSIONS: This is the first study of its kind where kidney biopsy practices are examined against a clinical guideline. Furthermore, responses showed that practices were incongruent with guidelines and that there was a lack of consensus on many issues.


Assuntos
Biópsia/estatística & dados numéricos , Fidelidade a Diretrizes/estatística & dados numéricos , Rim/patologia , Nefrologistas/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Australásia , Biópsia/efeitos adversos , Biópsia/métodos , Estudos Transversais , Humanos , Nefropatias/patologia , Guias de Prática Clínica como Assunto , Inquéritos e Questionários
19.
Proc Biol Sci ; 287(1936): 20201360, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33049170

RESUMO

Changes in size strongly influence organisms' ecological performances. For aquatic organisms, they can transition from viscosity- to inertia-dominated fluid regimes as they grow. Such transitions are often associated with changes in morphology, swimming speed and kinematics. Barnacles do not fit into this norm as they have two morphologically distinct planktonic larval phases that swim differently but are of comparable sizes and operate in the same fluid regime (Reynolds number 100-101). We quantified the hydrodynamics of the rocky intertidal stalked barnacle Capitulum mitella from the nauplius II to cyprid stage and examined how kinematics and size increases affect its swimming performance. Cyprids beat their appendages in a metachronal wave to swim faster, more smoothly, and with less backwards slip per beat cycle than did all naupliar stages. Micro-particle image velocimetry showed that cyprids generated trailing viscous vortex rings that pushed water backwards for propulsion, contrary to the nauplii's forward suction current for particle capture. Our observations highlight that zooplankton swimming performance can shift via morphological and kinematic modifications without a significant size increase. The divergence in ecological functions through ontogeny in barnacles and the removal of feeding requirement likely contributed to the evolution of the specialized, taxonomically unique cyprid phase.


Assuntos
Natação/fisiologia , Thoracica/fisiologia , Animais , Fenômenos Biomecânicos , Extremidades , Hidrodinâmica , Larva/fisiologia , Reologia , Zooplâncton
20.
Phys Rev Lett ; 125(21): 216402, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33274982

RESUMO

Trigonal tellurium, a small-gap semiconductor with pronounced magneto-electric and magneto-optical responses, is among the simplest realizations of a chiral crystal. We have studied by spin- and angle-resolved photoelectron spectroscopy its unconventional electronic structure and unique spin texture. We identify Kramers-Weyl, composite, and accordionlike Weyl fermions, so far only predicted by theory, and show that the spin polarization is parallel to the wave vector along the lines in k space connecting high-symmetry points. Our results clarify the symmetries that enforce such spin texture in a chiral crystal, thus bringing new insight in the formation of a spin vectorial field more complex than the previously proposed hedgehog configuration. Our findings thus pave the way to a classification scheme for these exotic spin textures and their search in chiral crystals.

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