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1.
Clin Radiol ; 79(3): 230-236, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38092646

RESUMO

AIM: To assess the accuracy of Magnetic Resonance Index of Activity (MaRIA) in evaluating therapeutic efficacy in Crohn's disease (CD) patients with different activity levels using ileocolonoscopy as the reference standard. MATERIALS AND METHODS: Forty-eight patients underwent magnetic resonance enterography (MRE) and ileocolonoscopy at baseline, week 26, and week 52, along with the Simple Endoscopic Score for Crohn's Disease (SES-CD) and MaRIA scores. According to the SES-CD score at baseline, all patients were subdivided into mild, moderate, and severe activity subgroups. The identification of endoscopic mucosal healing (MH) was explored primarily. Moreover, the Crohn's Disease Activity Index (CDAI), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), procalcitonin (PCT), and interleukin-6 (IL-6) levels were collected and analysed. RESULTS: MaRIA correlated significantly with SES-CD and CRP at baseline, week 26, and week 52. The discrepancies in MaRIA and SES-CD were statistically significant before and after treatment. MaRIA = 24.43 and ΔMaRIA = 12.77 as the cut-off points were found to have high diagnostic accuracy for predicting MH. MaRIA (p<0.001), SES-CD (p<0.001), CRP (p<0.05), ESR (p<0.05), and CDAI score (p<0.05) in patients with MH were considerably decreased compared to those in patients without MH. CONCLUSIONS: MRE has good application value in evaluating the therapeutic response of CD patients treated with biological agents. MaRIA is a reliable indicator in the follow-up of CD patients, which is strongly correlated with SES-CD, and it has high accuracy in predicting endoscopic MH.


Assuntos
Doença de Crohn , Humanos , Doença de Crohn/diagnóstico por imagem , Doença de Crohn/tratamento farmacológico , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Índice de Gravidade de Doença
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.
Nature ; 544(7648): 53-58, 2017 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-28355185

RESUMO

Although many aspects of blood production are well understood, the spatial organization of myeloid differentiation in the bone marrow remains unknown. Here we use imaging to track granulocyte/macrophage progenitor (GMP) behaviour in mice during emergency and leukaemic myelopoiesis. In the steady state, we find individual GMPs scattered throughout the bone marrow. During regeneration, we observe expanding GMP patches forming defined GMP clusters, which, in turn, locally differentiate into granulocytes. The timed release of important bone marrow niche signals (SCF, IL-1ß, G-CSF, TGFß and CXCL4) and activation of an inducible Irf8 and ß-catenin progenitor self-renewal network control the transient formation of regenerating GMP clusters. In leukaemia, we show that GMP clusters are constantly produced owing to persistent activation of the self-renewal network and a lack of termination cytokines that normally restore haematopoietic stem-cell quiescence. Our results uncover a previously unrecognized dynamic behaviour of GMPs in situ, which tunes emergency myelopoiesis and is hijacked in leukaemia.


Assuntos
Autorrenovação Celular , Células Progenitoras de Granulócitos e Macrófagos/citologia , Células Progenitoras de Granulócitos e Macrófagos/patologia , Leucemia/patologia , Mielopoese , Células-Tronco Neoplásicas/patologia , Animais , Reprogramação Celular , Citocinas/metabolismo , Granulócitos/citologia , Granulócitos/patologia , Fatores Reguladores de Interferon/metabolismo , Macrófagos/citologia , Macrófagos/patologia , Camundongos , Imagem Molecular , Nicho de Células-Tronco/fisiologia , beta Catenina/metabolismo
4.
Hong Kong Med J ; 29(5): 412-420, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37794613

RESUMO

INTRODUCTION: Telemedicine services worldwide have experienced unprecedented growth since the early days of the coronavirus disease 2019 (COVID-19) pandemic. Multiple studies have shown that telemedicine is an effective alternative to conventional in-person patient care. This study explored the public perception of telemedicine in Hong Kong, specifically among older adults who are most vulnerable to COVID-19. METHODS: Medical students from The Chinese University of Hong Kong conducted in-person surveys of older adults aged ≥60 years. Each survey collected socio-demographic information, medical history, and concerns regarding telemedicine use. Univariate and multivariate logistic regression analyses were conducted to identify statistically significant associations. The primary outcomes were acceptance of telemedicine use during a hypothetical severe outbreak and after the COVID-19 pandemic. RESULTS: There were 109 survey respondents. Multivariate logistic regression analyses revealed that the expectation of government subsidies for telemedicine services was the strongest common driver and the only positive independent predictor of telemedicine use during a hypothetical severe outbreak (P=0.016) and after the COVID-19 pandemic (P=0.003). No negative independent predictors of telemedicine use during a hypothetical severe outbreak were identified. Negative independent predictors of telemedicine use after the COVID-19 pandemic included older age and residence in the New Territories (both P=0.001). CONCLUSION: Government support, such as telemedicine-specific subsidies, will be important for efforts to promote telemedicine use in Hong Kong during future severe outbreaks and after the COVID-19 pandemic. Robust dissemination of information regarding the advantages and disadvantages of telemedicine for the public, especially older adults, is needed.


Assuntos
COVID-19 , Telemedicina , Humanos , Idoso , COVID-19/epidemiologia , Hong Kong/epidemiologia , Pandemias , Estudos Transversais
5.
Zhonghua Nei Ke Za Zhi ; 62(6): 688-692, 2023 Jun 01.
Artigo em Zh | MEDLINE | ID: mdl-37263952

RESUMO

Objective: To investigate the lifespan of erythrocytes in megaloblastic anemia (MA) patients. Methods: A prospective cohort study analysis. Clinical data from 42 MA patients who were newly diagnosed at the Department of Hematology, Lanzhou University Second Hospital from January 2021 to August 2021 were analyzed, as were control data from 24 healthy volunteers acquired during the same period. The carbon monoxide breath test was used to measure erythrocyte lifespan, and correlations between erythrocyte lifespan and laboratory test indexes before and after treatment were calculated. Statistical analysis included the t-test and Pearson correlation. Results: The mean erythrocyte lifespan in the 42 newly diagnosed MA patients was (49.05±41.60) d, which was significantly shorter than that in the healthy control group [(104.13±42.62) d; t=5.13,P=0.001]. In a vitamin B12-deficient subset of MA patients the mean erythrocyte lifespan was (30.09±15.14) d, and in a folic acid-deficient subgroup it was (72.00±51.44) d, and the difference between these two MA subsets was significant (t=3.73, P=0.001). The mean erythrocyte lifespan after MA treatment was (101.28±33.02) d, which differed significantly from that before MA treatment (t=4.72, P=0.001). In MA patients erythrocyte lifespan was positively correlated with hemoglobin concentration (r=0.373), and negatively correlated with total bilirubin level (r=-0.425), indirect bilirubin level (r=-0.431), and lactate dehydrogenase level (r=-0.504) (all P<0.05). Conclusions: Erythrocyte lifespan was shortened in MA patients, and there was a significant difference between a vitamin B12-deficient group and a folic acid-deficient group. After treatment the erythrocyte lifespan can return to normal. Erythrocyte lifespan is expected to become an informative index for the diagnosis and treatment of MA.


Assuntos
Anemia Megaloblástica , Longevidade , Humanos , Relevância Clínica , Estudos Prospectivos , Eritrócitos , Ácido Fólico , Bilirrubina , Vitaminas
6.
Hong Kong Med J ; 28(3): 230-238, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35667869

RESUMO

BACKGROUND: Neoadjuvant chemoradiotherapy is a standard treatment for locally advanced rectal cancer, for which pathological complete response is typically used as a surrogate survival endpoint. Neoadjuvant rectal score is a new biomarker that has been shown to correlate with survival. The main objectives of this study were to investigate factors contributing to pathological complete response, to validate the prognostic significance of neoadjuvant rectal score, and to investigate factors associated with a lower neoadjuvant rectal score in a cohort of Hong Kong Chinese. METHODS: Data of patients with locally advanced rectal cancer who received neoadjuvant chemoradiotherapy from August 2006 to October 2018 were retrieved from hospital records and retrospectively analysed. RESULTS: Of 193 patients who had optimal response to neoadjuvant chemoradiotherapy and surgery, tumour down-staging was the only independent prognostic factor that predicted pathological complete response (P<0.0001). Neoadjuvant rectal score was associated with overall survival (hazard ratio [HR]=1.042, 95% confidence interval [CI]=1.021-1.064; P<0.0001), disease-free survival (HR=1.042, 95% CI=1.022-1.062; P<0.0001), locoregional recurrence-free survival (HR=1.070, 95% CI=1.039-1.102; P<0.0001) and distant recurrence-free survival (HR=1.034, 95% CI=1.012-1.056; P=0.002). Patients who had pathological complete response were associated with a lower neoadjuvant rectal score (P<0.0001), but pathological complete response was not associated with survival. For patients with intermediate neoadjuvant rectal scores, late recurrences beyond 72 months from diagnosis were observed. CONCLUSION: Neoadjuvant rectal score is an independent prognostic marker of survival and disease recurrence in a cohort of Hong Kong Chinese patients who received neoadjuvant chemoradiotherapy for locally advanced rectal cancer.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Biomarcadores , Quimiorradioterapia , Intervalo Livre de Doença , Hong Kong , Humanos , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Estudos Retrospectivos , Resultado do Tratamento
7.
J Microsc ; 281(1): 57-75, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32720710

RESUMO

Time-lapse confocal fluorescence microscopy images from mouse embryonic stem cells (ESCs) carrying reporter genes, histone H2B-mCherry and Mvh-Venus, have been used to monitor dynamic changes in cellular/differentiation characteristics of live ESCs. Accurate cell nucleus segmentation is required to analyse the ESC dynamics and differentiation at a single cell resolution. Several methods used concavities on nucleus contours to segment overlapping cell nuclei. Our proposed method evaluates not only the concavities but also the size and shape of every 2D nucleus region to determine if any of the strait, extrusion, convexity and large diameter criteria is satisfied to segment overlapping nuclei inside the region. We then use a 3D segmentation method to reconstruct simple, convex, and reasonably sized 3D nuclei along the image stacking direction using the radius and centre of every segmented region in respective microscopy images. To avoid false concavities on nucleus boundaries, fluorescence images of the H2B-mCherry reporter are used for localisation of cell nuclei and Venus fluorescence images are used for determining the cell colony ranges. We use a series of image preprocessing procedures to remove noise outside and inside cell colonies, and in respective nuclei, and to smooth nucleus boundaries based on the colony ranges.  We propose dynamic data structures to record every segmented nucleus region and solid in sets (volumes) of 3D confocal images. The experimental results show that the proposed image preprocessing method preserves the areas of mouse ESC nuclei on microscopy images and that the segmentation method effectively segment out every nucleus with a reasonable size and shape. All 3D nuclei in a set (volume) of confocal microscopy images can be accessed by the dynamic data structures for 3D reconstruction. The 3D nuclei in time-lapse confocal microscopy images can be tracked to calculate cell movement and proliferation in consecutive volumes for understanding the dynamics of the differentiation characteristics about ESCs. LAY DESCRIPTION: Embryonic stem cells (ESCs) are considered as an ideal source for basic cell biology study and producing medically useful cells in vitro. This study uses time-lapse confocal fluorescence microscopy images from mouse ESCs carrying reporter gene to monitor dynamic changes in cellular/differentiation characteristics of live ESCs. To automate analyses of ESC differentiation behaviours, accurate cell nucleus segmentation to distinguish respective cells are required. A series of image preprocessing procedures are implemented to remove noise in live-cell fluorescence images but yield overlapping cell nuclei. A segmentation method that evaluates boundary concavities and the size and shape of every nucleus is then used to determine if any of the strait, extrusion, convexity, large and local minimum diameter criteria satisfied to segment overlapping nuclei. We propose a dynamic data structure to record every newly segmented nucleus. The experimental results show that the proposed image preprocessing method preserves the areas of mouse ESC nuclei and that the segmentation method effectively detects overlapping nuclei. All segmented nuclei in confocal images can be accessed using the dynamic data structures to be visualised and manipulated for quantitative analyses of the ESC differentiation behaviours. The manipulation can be tracking of segmented 3D cell nuclei in time-lapse images to calculate their dynamics of differentiation characteristics.


Assuntos
Núcleo Celular , Células-Tronco Embrionárias Murinas , Algoritmos , Animais , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Camundongos , Microscopia Confocal , Microscopia de Fluorescência
8.
Ultrasound Obstet Gynecol ; 58(5): 677-687, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34309931

RESUMO

OBJECTIVE: To investigate the effect of restriction measures implemented to mitigate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission during the coronavirus disease 2019 (COVID-19) pandemic on pregnancy duration and outcome. METHODS: A before-and-after study was conducted with cohort sampling in three maternity hospitals in Melbourne, Australia, including women who were pregnant when restriction measures were in place during the COVID-19 pandemic (estimated conception date between 1 November 2019 and 29 February 2020) and women who were pregnant before the restrictions (estimated conception date between 1 November 2018 and 28 February 2019). The primary outcome was delivery before 34 weeks' gestation or stillbirth. The main secondary outcome was a composite of adverse perinatal outcomes. Pregnancy outcomes were compared between women exposed to restriction measures and unexposed controls using the χ-square test and modified Poisson regression models, and duration of pregnancy was compared between the groups using survival analysis. RESULTS: In total, 3150 women who were exposed to restriction measures during pregnancy and 3175 unexposed controls were included. Preterm birth before 34 weeks or stillbirth occurred in 95 (3.0%) exposed pregnancies and in 130 (4.1%) controls (risk ratio (RR), 0.74 (95% CI, 0.57-0.96); P = 0.021). Preterm birth before 34 weeks occurred in 2.4% of women in the exposed group and in 3.4% of women in the control group (RR, 0.71 (95% CI, 0.53-0.95); P = 0.022), without evidence of an increase in the rate of stillbirth in the exposed group (0.7% vs 0.9%; RR, 0.83 (95% CI, 0.48-1.44); P = 0.515). Competing-risks regression analysis showed that the effect of the restriction measures on spontaneous preterm birth was stronger and started earlier (subdistribution hazard ratio (HR), 0.81 (95% CI, 0.64-1.03); P = 0.087) than the effect on medically indicated preterm birth (subdistribution HR, 0.89 (95% CI, 0.70-1.12); P = 0.305). The effect was stronger in women with a previous preterm birth (RR, 0.42 (95% CI, 0.21-0.82); P = 0.008) than in parous women without a previous preterm birth (RR, 0.93 (95% CI, 0.63-1.38); P = 0.714) (P for interaction = 0.044). Composite adverse perinatal outcome was less frequent in the exposed group than in controls (all women: 2.1% vs 2.9%; RR, 0.73 (95% CI, 0.54-0.99); P = 0.042); women with a previous preterm birth: 4.5% vs 8.4%; RR, 0.54 (95% CI, 0.25-1.18); P = 0.116). CONCLUSIONS: Restriction measures implemented to mitigate SARS-CoV-2 transmission during the COVID-19 pandemic were associated with a reduced rate of preterm birth before 34 weeks. This reduction was mainly due to a lower rate of spontaneous prematurity. The effect was more substantial in women with a previous preterm birth and was not associated with an increased stillbirth rate. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
COVID-19/prevenção & controle , Controle de Infecções/métodos , Pandemias/prevenção & controle , Resultado da Gravidez/epidemiologia , Adulto , Austrália/epidemiologia , COVID-19/epidemiologia , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Distanciamento Físico , Gravidez , Nascimento Prematuro/epidemiologia , SARS-CoV-2 , Natimorto/epidemiologia , Adulto Jovem
9.
J Acoust Soc Am ; 150(5): 3445, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34852584

RESUMO

The sound propagation across a sound leaking section along an infinite rectangular duct-like structure near to the lower order duct eigenfrequencies is investigated numerically in the present study. The sound leakage is achieved by finite length rectangular slots located at a corner of the duct-like structure cross section. The finite-element simulations are performed, in the first place, to gain insights into the modal development inside the structure. A semi-analytical model, which considers the wavy air motions along the slots with oblique sound radiation patterns, is developed. An empirical framework is also proposed to estimate the complex longitudinal wavenumber along the slot using the numerical results and dimensional analysis. The performance of the proposed semi-analytical model, together with the complex wavenumber prediction framework, is tested using two duct-like structures with different cross section aspect ratios. The results show that the present proposed approach gives predictions close to the finite-element simulations. The deviations are well within engineering tolerance.

10.
Hong Kong Med J ; 27(6): 405-412, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34924363

RESUMO

INTRODUCTION: The effect of massage for pain relief during labour has been controversial. This study investigated the efficacy of a programme combining intrapartum massage, controlled breathing, and visualisation for non-pharmacological pain relief during labour. METHODS: This randomised controlled trial was conducted in two public hospitals in Hong Kong. Participants were healthy low-risk nulliparous Chinese women ≥18 years old whose partners were available to learn massage technique. Recruitment was performed at 32 to 36 weeks of gestation; women were randomised to attend a 2-hour childbirth massage class at 36 weeks of gestation or to receive usual care. The primary outcome variable was the intrapartum use of epidural analgesia or intramuscular pethidine injection. RESULTS: In total, 233 and 246 women were randomised to the massage and control groups, respectively. The use of epidural analgesia or pethidine did not differ between the massage and control groups (12.0% vs 15.9%; P=0.226). Linear-by-linear analysis demonstrated a trend whereby fewer women used strong pharmacological pain relief in the massage group, and a greater proportion of women had analgesic-free labour (29.2% vs 21.5%; P=0.041). Cervical dilatation at the time of pethidine/epidural analgesia request was significantly greater in the massage group (3.8 ± 1.7 cm vs 2.3 ± 1.0 cm; P<0.001). CONCLUSION: The use of a massage programme appeared to modulate pain perception in labouring women, such that fewer women requested epidural analgesia and a shift was observed towards the use of weaker pain relief modalities; in particular, more women in the massage group were analgesic-free during labour.


Assuntos
Analgesia Obstétrica , Dor do Parto , Adolescente , Feminino , Humanos , Dor do Parto/terapia , Massagem , Parto , Satisfação do Paciente , Gravidez , Gestantes
11.
Zhonghua Yi Xue Za Zhi ; 100(24): 1895-1900, 2020 Jun 23.
Artigo em Zh | MEDLINE | ID: mdl-32575935

RESUMO

Objective: To analyze the level and trend of respiratory disease mortality in China from 2002 to 2016. Methods: The standardized mortality rates were calculated based on the China health statistics yearbook (2003-2012) and China statistical yearbook of health and family planning (2013-2017) data released by the statistical information center of National health Commission of the People's Republic of China. Joinpoint model was used to calculate the standardized mortality rates (SMR), Annual percentage change (APC) and the average annual percentage change (AAPC) for standardized mortality rates. Results: The SMR of respiratory diseases and chronic lower respiratory diseases were decreased significantly in 2002 to 2016 (AAPC=-3.6%, AAPC=-6.4%, P<0.001, respectively). The SMR of lung cancer showed a significant increase trend (AAPC=1.6%, P=0.001). There were no significant differences in the SMR of pneumonia and pneumonoconiosis (APCC=1.0%, P=0.242; APCC=-0.2%, P=0.905). Both urban and rural SMR of respiratory diseases were declining significantly (AAPC=-2.9%, P=0.001; AAPC=-4.2%, P<0.001). Both urban and rural SMR of lung cancer showed an increasing trend (AAPC=0.6%, P=0.022; AAPC=2.1%, P=0.003, respectively). The SMR of pneumonia in urban areas showed an upward trend (AAPC=2.7%, P=0.017). The SMR of respiratory disease of all age groups (<35 years old, 35-65 years old and ≥65 years old) showed a downward trend (AAPC=-3.8%, P=0.001; AAPC=-2.6%, P<0.001; AAPC=-3.9%, P<0.001). The SMR of pneumonia between 35 and 65 years old and SMR of lung cancer over 65 years old showed an increasing trend (AAPC=2.8%, P=0.001; AAPC=2.4%, P<0.001). The SMR of respiratory diseases among males and females showed a downtrend (AAPC=-3.1%, P<0.001; AAPC=-4.3%, P<0.001). However, the SMR of lung cancer in males and females increased significantly (AAPC=1.2%, P<0.001; AAPC=2.5%, P<0.001, respectively). There were no significant trends in the SMR of pneumonia and pneumoconiosis in males (AAPC=1.5%, P=0.096; AAPC=-1.6%, P=0.218). There was no obvious trend in the SMR of pneumonia in females (AAPC=-0.1%, P=0.872). Conclusions: The SMR of respiratory diseases in China generally shows a downward trend. The overall SMR and SMR of major respiratory diseases varies among different regions, genders and age groups.


Assuntos
Neoplasias Pulmonares , Pneumonia , Adulto , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , População Rural
12.
Plant J ; 96(6): 1148-1159, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30238531

RESUMO

The reference genome sequence of wheat 'Chinese Spring' (CS) is now available (IWGSC RefSeq v1.0), but the core sequences defining the nucleolar organizer regions (NORs) have not been characterized. We estimated that the total copy number of the rDNA units in the wheat genome is 11 160, of which 30.5%, 60.9% and 8.6% are located on Nor-B1 (1B), Nor-B2 (6B) and other NORs, respectively. The total length of the NORs is estimated to be 100 Mb, corresponding to approximately 10% of the unassembled portion of the genome not represented in RefSeq v1.0. Four subtypes (S1-S4) of the rDNA units were identified based on differences within the 3' external transcribed spacer regions in Nor-B1 and Nor-B2, and quantitative PCR indicated locus-specific variation in rDNA subtype contents. Expression analyses of rDNA subtypes revealed that S1 was predominantly expressed and S2 weakly expressed, in contrast to the relative abundance of rDNA subtypes in the wheat genome. These results suggest a regulation mechanism of differential rDNA expression based on sequence differences. S3 expression increased in the ditelosomic lines Dt1BL and Dt6BL, suggesting that S3 is subjected to chromosome-mediated silencing. Structural differences were detected in the regions surrounding the NOR among homoeologous chromosomes of groups 1 and 6. The adjacent regions distal to the major NORs were expanded compared with their homoeologous counterparts, and the gene density of these expanded regions was relatively low. We provide evidence that these regions are likely to be important for autoregulation of the associated major NORs as well as silencing of minor NORs.


Assuntos
Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Região Organizadora do Nucléolo/genética , RNA de Plantas/genética , RNA Ribossômico/genética , Triticum/genética , Cromossomos de Plantas/genética , Variações do Número de Cópias de DNA/genética , Loci Gênicos/genética , Genoma de Planta/genética , Hibridização in Situ Fluorescente , Região Organizadora do Nucléolo/metabolismo , Reação em Cadeia da Polimerase , RNA de Plantas/metabolismo , RNA Ribossômico/metabolismo , Triticum/metabolismo
13.
Blood ; 130(24): 2631-2641, 2017 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-29018079

RESUMO

Mutations in SETD2, encoding the histone 3 lysine 36 trimethyltransferase, are enriched in relapsed acute lymphoblastic leukemia and MLL-rearranged acute leukemia. We investigated the impact of SETD2 mutations on chemotherapy sensitivity in isogenic leukemia cell lines and in murine leukemia generated from a conditional knockout of Setd2. SETD2 mutations led to resistance to DNA-damaging agents, cytarabine, 6-thioguanine, doxorubicin, and etoposide, but not to a non-DNA damaging agent, l-asparaginase. H3K36me3 localizes components of the DNA damage response (DDR) pathway and SETD2 mutation impaired DDR, blunting apoptosis induced by cytotoxic chemotherapy. Consistent with local recruitment of DDR, genomic regions with higher H3K36me3 had a lower mutation rate, which was increased with SETD2 mutation. Heterozygous conditional inactivation of Setd2 in a murine model decreased the latency of MLL-AF9-induced leukemia and caused resistance to cytarabine treatment in vivo, whereas homozygous loss delayed leukemia formation. Treatment with JIB-04, an inhibitor of the H3K9/36me3 demethylase KDM4A, restored H3K36me3 levels and sensitivity to cytarabine. These findings establish SETD2 alteration as a mechanism of resistance to DNA-damaging chemotherapy, consistent with a local loss of DDR, and identify a potential therapeutic strategy to target SETD2-mutant leukemias.


Assuntos
Dano ao DNA , Resistencia a Medicamentos Antineoplásicos/genética , Histona-Lisina N-Metiltransferase/genética , Leucemia Experimental/genética , Aminopiridinas/farmacologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Citarabina/farmacologia , Células HEK293 , Histona-Lisina N-Metiltransferase/deficiência , Histonas/metabolismo , Humanos , Hidrazonas/farmacologia , Leucemia Experimental/tratamento farmacológico , Lisina/metabolismo , Metilação/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Análise de Sobrevida
14.
J Dairy Sci ; 102(4): 3469-3473, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30712932

RESUMO

Bovine leukemia virus (BLV) causes enzootic leucosis in cattle and is classified into 10 genotypes with a worldwide distribution, except for several European countries, Australia, and New Zealand. Although BLV is widespread in Chinese cows with the positive rate of 49.1% at the individual level, very little is known about the BLV genotype in dairy cattle in China. To determine BLV genetic variability in cows in China, 112 BLV-positive samples from 5 cities in China were used for BLV molecular characterization in this study. Phylogenetic analysis using the neighbor-joining method on partial env sequence encoding gp51 obtained from 5 Chinese cities and those available in GenBank (n = 53, representing BLV genotype 1-10) revealed the Chinese strains belonged to genotype 6. Seven unique SNP were identified among Yancheng, Shanghai, and Bengbu strains out of the total 12 SNP identified in Chinese strains. The genotyping coupled with SNP analysis of BLV can serve as a useful molecular epidemiological tool for tracing the source of pathogens. This study highlights the importance of genetic analysis of geographically diverse BLV strains to understand BLV global genetic diversity.


Assuntos
Leucose Enzoótica Bovina/virologia , Genótipo , Vírus da Leucemia Bovina/genética , Epidemiologia Molecular , Polimorfismo de Nucleotídeo Único , Animais , Bovinos , China/epidemiologia , Leucose Enzoótica Bovina/epidemiologia , Feminino
15.
Zhonghua Xin Xue Guan Bing Za Zhi ; 46(5): 376-381, 2018 May 24.
Artigo em Zh | MEDLINE | ID: mdl-29804440

RESUMO

Objective: To explore the impact of PI3K-Akt-eNOS signaling on atrial fibrillation inducibility in diabetic rats. Method: Eight-week-old male diabetic rats were randomized assigned into GK group, IGF group and L-NAME group (n=8 each) which respectively received normal saline (NS), insulin like growth factor (IGF-1) or L-NAME+IGF-1 through tail vein daily for 4 weeks. Eight 8-week-old male homologous Wister-Kyoto(WKY) rats treated with intravenous NS served as control group (WKY group). Blood glucose was measured once per week. The left atrial diameter (LAD) was measured by echocardiography, the atrial electrical parameters, including the P-wave duration, the atrial effective refractory period (AERP) and its dispersion (AERP-d), the incidence and the duration of atrial fibrillation induced by atrial burst pacing, were evaluated by electro-physiological instrument at 4 weeks post various treatments. Rats were then sacrificed, left atrial (LA) cell morphology was determined on HE stained sections, LA interstitial collagen was determined on Masson stained sections. The protein expression of phosphatidylinositol 3-kinase (PI3K) and phosphate endothelial nitric oxide synthase (p-eNOS) were detected by Western blot. Results: (1) At the beginning of the study, the random blood glucose (GLU) level was significantly higher and LAD was large in GK, IGF and L-NAME groups than in WKY group;after 4 weeks, GLU level and LAD dimension of IGF group were lower than GK and L-NAME groups (P<0.01 or 0.05). (2) One rat in L-NAME group died during operation. Four weeks later, the incidence of atrial fibrillation in GK group, IGF group, L-NAME group and WKY group was 7/8, 2/8, 6/7 and 3/8. The median duration of atrial fibrillation in GK group, IGF group, L-NAME group and WKY group was 11.9(9.3, 13.1), 0(0, 1.8), 11.5(4.4, 12.0), and 0(0, 3.0) s. Compare with WKY group, the P-wave duration and PR interval were significantly longer, AERP-d, incidence, and duration of atrial fibrillation were significantly higher in GK group (P<0.01), these changed were significantly reversed in IGF group compared to GK and L-NAME groups (all P<0.01). Heart rate and AERP were similar among the 4 groups on (P>0.05). (3) Four weeks later, the CSA and CVF of LA were significantly larger in GK group than in WKY group (P<0.01), which were significantly reversed in IGF group (P<0.01 vs. GK group), and the beneficial effects of IGF disappeared by co-treatment with L-NAME (P<0.01 vs. IGF group). (4) Four weeks later, compare with WKY group, the protein expression of PI3K (P<0.01) and p-eNOS (P<0.05) of LA were significantly downregulated in GK group, which could be significantly upregulated by IGF (P<0.01 and 0.05 vs. GK group), these effects diminished by co-treatment with L-NAME (P<0.01 or 0.05 vs. IGF group). Conclusion: Increased atrial fibrillation susceptibility in diabetic rat is linked with structural and electrical remodeling in LA, possibly mediated through downregulated PI3K-Akt-eNOS signaling.


Assuntos
Fibrilação Atrial , Diabetes Mellitus Experimental , Óxido Nítrico Sintase Tipo III , Fosfatidilinositol 3-Quinase , Animais , Fibrilação Atrial/etiologia , Diabetes Mellitus Experimental/metabolismo , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Distribuição Aleatória , Ratos , Ratos Endogâmicos WKY
16.
Clin Genet ; 91(2): 285-291, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27813081

RESUMO

Ovarian sex cord-stromal tumors (SCST) represent approximately 8% of malignant ovarian tumors. The most common are granulosa cell tumors (GCT) which account for approximately 90% of malignant SCST. Recent studies have unraveled the key genomic and genetic events contributing to their pathogenesis. SCST are found in the hereditary syndromes: Peutz-Jeghers syndrome, Ollier disease and Maffucci syndrome, and DICER1 syndrome. Genomic studies have largely been limited to GCT where a number of recurring chromosomal abnormalities (monsomy and trisomy) have been identified although their contribution to pathogenesis remains unclear. In addition to the recurrent DICER1 mutations reported in non-hereditary cases of Sertoli cell and Sertoli-Leydig cell tumors, recurrent somatic mutations in both the juvenile (j) and adult (a) forms of GCT have been reported. Approximately 30% of jGCT contain a somatic mutation, the gsp oncogene, while a further 60% have an activating mutation in the AKT gene. In the case of aGCT, a well characterized mutation in the FOXL2 transcription factor (FOXL2 C134W) is found in almost all cases, which arguably defines the disease, although the molecular events that determine the stage, behavior and prognosis of aGCT remain to be determined.


Assuntos
Fatores de Transcrição Forkhead/genética , Tumor de Células da Granulosa/genética , Neoplasias Ovarianas/genética , Tumor de Células de Sertoli-Leydig/genética , Tumores do Estroma Gonadal e dos Cordões Sexuais/genética , Adulto , RNA Helicases DEAD-box/genética , Feminino , Proteína Forkhead Box L2 , Genômica , Tumor de Células da Granulosa/patologia , Humanos , Masculino , Mutação , Neoplasias Ovarianas/patologia , Síndrome de Peutz-Jeghers/genética , Síndrome de Peutz-Jeghers/patologia , Ribonuclease III/genética , Tumor de Células de Sertoli-Leydig/patologia , Tumores do Estroma Gonadal e dos Cordões Sexuais/patologia
17.
Gynecol Oncol ; 145(3): 453-461, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28236454

RESUMO

OBJECTIVE: Natural killer (NK) cells represent a powerful immunotherapeutic target as they lyse tumors directly, do not require differentiation, and can elicit potent inflammatory responses. The objective of these studies was to use an IL-15 super-agonist complex, ALT-803 (Altor BioScience Corporation), to enhance the function of both normal and ovarian cancer patient derived NK cells by increasing cytotoxicity and cytokine production. METHODS: NK cell function from normal donor peripheral blood mononuclear cells (PBMCs) and ovarian cancer patient ascites was assessed using flow cytometry and chromium release assays ±ALT-803 stimulation. To evaluate the ability of ALT-803 to enhance NK cell function in vivo against ovarian cancer, we used a MA148-luc ovarian cancer NOD scid gamma (NSG) xenogeneic mouse model with transferred human NK cells. RESULTS: ALT-803 potently enhanced functionality of NK cells against all ovarian cancer cell lines with significant increases seen in CD107a, IFNγ and TNFα expression depending on target cell line. Function was also rescued in NK cells derived from ovarian cancer patient ascites. Finally, only animals treated with intraperitoneal ALT-803 displayed an NK dependent significant decrease in tumor. CONCLUSIONS: ALT-803 enhances NK cell cytotoxicity against ovarian cancer in vitro and in vivo and is able to rescue functionality of NK cells derived from ovarian cancer patient ascites. These findings suggest that ALT-803 has the potential to enhance NK cell-based immunotherapeutic approaches for the treatment of ovarian cancer.


Assuntos
Interleucina-15/agonistas , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/imunologia , Proteínas/farmacologia , Animais , Ascite/imunologia , Ascite/patologia , Feminino , Humanos , Células K562 , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas Recombinantes de Fusão , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Zhonghua Yi Xue Za Zhi ; 97(44): 3488-3491, 2017 Nov 28.
Artigo em Zh | MEDLINE | ID: mdl-29275585

RESUMO

Objective: To investigate the impact of the implementation of Beijing Tobacco Control Regulation on outpatient visits for smoking cessation in Beijing Chaoyang Hospital. Methods: The outpatient visits and the proportion of returned cases to the total outpatient visits for smoking cessation in Beijing Chaoyang Hospital in past five years (2012-2016) that was before and after the implementation of Beijing Tobacco Control Regulation (June 1(st,) 2015) were analyzed. Time series seasonal index method was used to analyze seasonal variations in the outpatient visits. Results: From the implementation of Beijing Tobacco Control Regulation to December 31(th,) 2016, the average monthly outpatient visits for smoking cessation was significantly increased compared to that before the implementation [(101±37) vs (48±17), t=-7.486, P<0.001]. Meanwhile, the proportion of returned cases to the total outpatient visits was also significantly increased compared to that before the implementation [30.4% (582/1 912) vs 8.2% (161/1 966); χ(2)=309.8, P<0.001]. In addition, there were seasonal fluctuations in the number of outpatients from 2012 to 2016 , during which the outpatient visits started to increase in the second and third quarter (summer and fall) and peaked in June, but became less in the first and fourth quarter (spring and winter), and reached its nadir in January. Conclusions: With the implementation of Beijing Tobacco Control Regulation, the outpatient visits for smoking cessation have increased. Moreover, there is seasonal fluctuation in the outpatient visits for smoking cessation.


Assuntos
Pacientes Ambulatoriais , Abandono do Hábito de Fumar , Controle Social Formal , Pequim , Hospitais , Humanos , Nicotiana
20.
Clin Radiol ; 71(6): 507-12, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27040800

RESUMO

AIM: To compare the safety and efficacy of percutaneous computed tomography (CT)-guided core-needle biopsy (CNB) of pancreatic masses traversing the gastrointestinal tract or solid viscera versus trans-mesenteric and retroperitoneal approaches. MATERIALS AND METHODS: CT-guided CNB of pancreatic lesions performed between May 2004 and December 2014 were retrospectively analysed at a single centre. Biopsies were performed using 18- or 20-G needles with a coaxial system. CT images, histopathology reports, medical records, and procedural details for all patients were reviewed to evaluate the biopsy route, complications, and diagnostic accuracy. According to the routes, biopsies were divided into trans-mesenteric, retroperitoneal and trans-organ approaches for comparison. RESULTS: A total of 85 patients, who had undergone 89 CNBs for pancreatic masses were reviewed. The overall sensitivity, specificity, and accuracy of CNB for detecting malignancy via various routes were 88.8%, 100%, and 89.9%, respectively, with a complication rate of 20.2%. Trans-organ biopsies of pancreatic masses (n=22) were performed safely via a direct pathway traversing the stomach (n=14), colon (n=3), small bowel (n=2), liver (n=2), and spleen (n=1). The sensitivity, specificity, and accuracy were 90.5%, 100%, and 90.9%, respectively. In the trans-organ biopsy group, three biopsies (13.6%) resulted in minor haematomas, but no major complications occurred. There were no statistically significant differences in the diagnostic efficacy or complication rate among the different biopsy routes. CONCLUSION: Percutaneous CT-guided CNB using a trans-organ approach is a feasible technique for diagnosing pancreatic malignancy; however, as this series was small, more data is required.


Assuntos
Biópsia com Agulha de Grande Calibre/métodos , Biópsia Guiada por Imagem/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Radiografia Intervencionista/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia com Agulha de Grande Calibre/efeitos adversos , Humanos , Biópsia Guiada por Imagem/efeitos adversos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
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