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1.
Brief Bioinform ; 25(2)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38436557

RESUMEN

Spatial transcriptomics technologies have shed light on the complexities of tissue structures by accurately mapping spatial microenvironments. Nonetheless, a myriad of methods, especially those utilized in platforms like Visium, often relinquish spatial details owing to intrinsic resolution limitations. In response, we introduce TransformerST, an innovative, unsupervised model anchored in the Transformer architecture, which operates independently of references, thereby ensuring cost-efficiency by circumventing the need for single-cell RNA sequencing. TransformerST not only elevates Visium data from a multicellular level to a single-cell granularity but also showcases adaptability across diverse spatial transcriptomics platforms. By employing a vision transformer-based encoder, it discerns latent image-gene expression co-representations and is further enhanced by spatial correlations, derived from an adaptive graph Transformer module. The sophisticated cross-scale graph network, utilized in super-resolution, significantly boosts the model's accuracy, unveiling complex structure-functional relationships within histology images. Empirical evaluations validate its adeptness in revealing tissue subtleties at the single-cell scale. Crucially, TransformerST adeptly navigates through image-gene co-representation, maximizing the synergistic utility of gene expression and histology images, thereby emerging as a pioneering tool in spatial transcriptomics. It not only enhances resolution to a single-cell level but also introduces a novel approach that optimally utilizes histology images alongside gene expression, providing a refined lens for investigating spatial transcriptomics.


Asunto(s)
Perfilación de la Expresión Génica , Expresión Génica
2.
Lancet Oncol ; 25(1): 99-107, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38043558

RESUMEN

BACKGROUND: The TheraP study reported improved prostate-specific antigen responses with lutetium-177 [177Lu]Lu-PSMA-617 versus cabazitaxel in men with metastatic castration-resistant prostate cancer progressing after docetaxel. In this Article, we report the secondary outcome of overall survival with mature follow-up, and an updated imaging biomarker analysis. We also report the outcomes of participants excluded due to ineligibility on gallium-68 [68Ga]Ga-PSMA-11 and 2-[18F]fluoro-2-deoxy-D-glucose (2-[18F]FDG) PET-CT. METHODS: TheraP was an open-label, randomised phase 2 trial at 11 centres in Australia. Eligible participants had metastatic castration-resistant prostate cancer progressing after docetaxel, and PET imaging with [68Ga]Ga-PSMA-11 and 2-[18F]FDG that showed prostate-specific membrane antigen (PSMA)-positive disease and no sites of metastatic disease with discordant 2-[18F]FDG-positive and PSMA-negative findings. Participants were randomly assigned (1:1) to treatment with [177Lu]Lu-PSMA-617 (every 6 weeks for a maximum of six cycles; starting at 8·5 GBq, decreasing by 0.5 GBq to 6·0 GBq for the sixth cycle) versus cabazitaxel (20 mg/m2 every 3 weeks, maximum of ten cycles). Overall survival was analysed by intention-to-treat and summarised as restricted mean survival time (RMST) to account for non-proportional hazards, with a 36-month restriction time corresponding to median follow-up. This trial is registered with ClinicalTrials.gov, NCT03392428, and is complete. FINDINGS: 291 men were registered from Feb 6, 2018, to Sept 3, 2019; after study imaging, 200 were eligible and randomly assigned to treatment with [177Lu]Lu-PSMA-617 (n=99) or cabazitaxel (n=101). After completing study treatment, 20 (20%) participants assigned to cabazitaxel and 32 (32%) assigned to [177Lu]Lu-PSMA-617 were subsequently treated with the alternative regimen. After a median follow-up of 35·7 months (IQR 31·1 to 39·2), 77 (78%) participants had died in the [177Lu]Lu-PSMA-617 group and 70 (69%) participants had died in the cabazitaxel group. Overall survival was similar among those assigned to [177Lu]Lu-PSMA-617 versus those assigned to cabazitaxel (RMST 19·1 months [95% CI 16·9 to 21·4] vs 19·6 months [17·4 to 21·8]; difference -0·5 months [95% CI -3·7 to 2·7]; p=0·77). No additional safety signals were identified with the longer follow-up in this analysis. 80 (27%) of 291 men who were registered after initial eligibility screening were excluded after [68Ga]Ga-PSMA-11 and 2-[18F]FDG PET. In the 61 of these men with follow-up available, RMST was 11·0 months (95% CI 9·0 to 13·1). INTERPRETATION: These results support the use of [177Lu]Lu-PSMA-617 as an alternative to cabazitaxel for PSMA-positive metastatic castration-resistant prostate cancer progressing after docetaxel. We did not find evidence that overall survival differed between the randomised groups. Median overall survival was shorter for men who were excluded because of low PSMA expression or 2-[18F]FDG-discordant disease. FUNDING: Australian and New Zealand Urogenital and Prostate Cancer Trials Group, Prostate Cancer Foundation of Australia, Endocyte (a Novartis company), Australian Nuclear Science and Technology Organization, Movember, It's a Bloke Thing, CAN4CANCER, and The Distinguished Gentleman's Ride.


Asunto(s)
Radioisótopos de Galio , Neoplasias de la Próstata Resistentes a la Castración , Masculino , Humanos , Resultado del Tratamiento , Docetaxel/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/radioterapia , Tomografía Computarizada por Tomografía de Emisión de Positrones , Fluorodesoxiglucosa F18 , Australia , Antígeno Prostático Específico
3.
Lancet Oncol ; 25(5): 563-571, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38621400

RESUMEN

BACKGROUND: Enzalutamide and lutetium-177 [177Lu]Lu-prostate-specific membrane antigen (PSMA)-617 both improve overall survival in patients with metastatic castration-resistant prostate cancer. Androgen and PSMA receptors have a close intracellular relationship, with data suggesting complementary benefit if targeted concurrently. In this study, we assessed the activity and safety of enzalutamide plus adaptive-dosed [177Lu]Lu-PSMA-617 versus enzalutamide alone as first-line treatment for metastatic castration-resistant prostate cancer. METHODS: ENZA-p was an open-label, randomised, controlled phase 2 trial done at 15 hospitals in Australia. Participants were men aged 18 years or older with metastatic castration-resistant prostate cancer not previously treated with docetaxel or androgen receptor pathway inhibitors for metastatic castration-resistant prostate cancer, gallium-68 [68Ga]Ga-PSMA-PET-CT (PSMA-PET-CT) positive disease, Eastern Cooperative Oncology Group performance status of 0-2, and at least two risk factors for early progression on enzalutamide. Participants were randomly assigned (1:1) by a centralised, web-based system using minimisation with a random component to stratify for study site, disease burden, use of early docetaxel, and previous treatment with abiraterone acetate. Patients were either given oral enzalutamide 160 mg daily alone or with adaptive-dosed (two or four doses) intravenous 7·5 GBq [177Lu]Lu-PSMA-617 every 6-8 weeks dependent on an interim PSMA-PET-CT (week 12). The primary endpoint was prostate-specific antigen (PSA) progression-free survival, defined as the interval from the date of randomisation to the date of first evidence of PSA progression, commencement of non-protocol anticancer therapy, or death. The analysis was done in the intention-to-treat population, using stratified Cox proportional hazards regression. This trial is registered with ClinicalTrials.gov, NCT04419402, and participant follow-up is ongoing. FINDINGS: 162 participants were randomly assigned between Aug 17, 2020, and July 26, 2022. 83 men were assigned to the enzalutamide plus [177Lu]Lu-PSMA-617 group, and 79 were assigned to the enzalutamide group. Median follow-up in this interim analysis was 20 months (IQR 18-21), with 32 (39%) of 83 patients in the enzalutamide plus [177Lu]Lu-PSMA-617 group and 16 (20%) of 79 patients in the enzalutamide group remaining on treatment at the data cutoff date. Median age was 71 years (IQR 64-76). Median PSA progression-free survival was 13·0 months (95% CI 11·0-17·0) in the enzalutamide plus [177Lu]Lu-PSMA-617 group and 7·8 months (95% CI 4·3-11·0) in the enzalutamide group (hazard ratio 0·43, 95% CI 0·29-0·63, p<0·0001). The most common adverse events (all grades) were fatigue (61 [75%] of 81 patients), nausea (38 [47%]), and dry mouth (32 [40%]) in the enzalutamide plus [177Lu]Lu-PSMA-617 group and fatigue (55 [70%] of 79), nausea (21 [27%]), and constipation (18 [23%]) in the enzalutamide group. Grade 3-5 adverse events occurred in 32 (40%) of 81 patients in the enzalutamide plus [177Lu]Lu-PSMA-617 group and 32 (41%) of 79 patients in the enzalutamide group. Grade 3 events that occurred only in the enzalutamide plus [177Lu]Lu-PSMA-617 group included anaemia (three [4%] of 81 participants) and decreased platelet count (one [1%] participant). No grade 4 or 5 events were attributed to treatment on central review in either group. INTERPRETATION: The addition of [177Lu]Lu-PSMA-617 to enzalutamide improved PSA progression-free survival providing evidence of enhanced anticancer activity in patients with metastatic castration-resistant prostate cancer with risk factors for early progression on enzalutamide and warrants further evaluation of the combination more broadly in metastatic prostate cancer. FUNDING: Prostate Cancer Research Alliance (Movember and Australian Federal Government), St Vincent's Clinic Foundation, GenesisCare, Roy Morgan Research, and Endocyte (a Novartis company).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Benzamidas , Dipéptidos , Compuestos Heterocíclicos con 1 Anillo , Lutecio , Nitrilos , Feniltiohidantoína , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/patología , Neoplasias de la Próstata Resistentes a la Castración/mortalidad , Feniltiohidantoína/administración & dosificación , Feniltiohidantoína/uso terapéutico , Feniltiohidantoína/análogos & derivados , Anciano , Dipéptidos/uso terapéutico , Dipéptidos/administración & dosificación , Dipéptidos/efectos adversos , Compuestos Heterocíclicos con 1 Anillo/uso terapéutico , Compuestos Heterocíclicos con 1 Anillo/administración & dosificación , Compuestos Heterocíclicos con 1 Anillo/efectos adversos , Persona de Mediana Edad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Antígeno Prostático Específico/sangre , Supervivencia sin Progresión , Radioisótopos/uso terapéutico , Anciano de 80 o más Años , Radiofármacos
4.
Mol Cell ; 64(6): 1074-1087, 2016 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-27889452

RESUMEN

Repetitive genomic regions include tandem sequence repeats and interspersed repeats, such as endogenous retroviruses and LINE-1 elements. Repressive heterochromatin domains silence expression of these sequences through mechanisms that remain poorly understood. Here, we present evidence that the retinoblastoma protein (pRB) utilizes a cell-cycle-independent interaction with E2F1 to recruit enhancer of zeste homolog 2 (EZH2) to diverse repeat sequences. These include simple repeats, satellites, LINEs, and endogenous retroviruses as well as transposon fragments. We generated a mutant mouse strain carrying an F832A mutation in Rb1 that is defective for recruitment to repetitive sequences. Loss of pRB-EZH2 complexes from repeats disperses H3K27me3 from these genomic locations and permits repeat expression. Consistent with maintenance of H3K27me3 at the Hox clusters, these mice are developmentally normal. However, susceptibility to lymphoma suggests that pRB-EZH2 recruitment to repetitive elements may be cancer relevant.


Asunto(s)
Factor de Transcripción E2F1/genética , Proteína Potenciadora del Homólogo Zeste 2/genética , Silenciador del Gen , Linfoma/genética , Secuencias Repetitivas de Ácidos Nucleicos , Proteína de Retinoblastoma/genética , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Factor de Transcripción E2F1/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Fibroblastos/citología , Fibroblastos/metabolismo , Predisposición Genética a la Enfermedad , Histonas/genética , Histonas/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Linfoma/metabolismo , Linfoma/mortalidad , Linfoma/patología , Mesenterio/metabolismo , Mesenterio/patología , Ratones , Mutación , Cultivo Primario de Células , Unión Proteica , Proteína de Retinoblastoma/metabolismo , Neoplasias del Bazo/genética , Neoplasias del Bazo/metabolismo , Neoplasias del Bazo/mortalidad , Neoplasias del Bazo/patología , Análisis de Supervivencia
5.
Cereb Cortex ; 32(22): 5216-5229, 2022 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-35106549

RESUMEN

Visual spatial working memory (vsWM) is mediated by a distributed cortical network composed of multiple nodes, including primary visual (V1), posterior parietal (PPC), and dorsolateral prefrontal (DLPFC) cortices. Feedforward and feedback information is transferred among these nodes via projections furnished by pyramidal neurons (PNs) located primarily in cortical layer 3. Morphological and electrophysiological differences among layer 3 PNs across these nodes have been reported; however, the transcriptional signatures underlying these differences have not been examined in the human brain. Here we interrogated the transcriptomes of layer 3 PNs from 39 neurotypical human subjects across 3 critical nodes of the vsWM network. Over 8,000 differentially expressed genes were detected, with more than 6,000 transcriptional differences present between layer 3 PNs in V1 and those in PPC and DLPFC. Additionally, over 600 other genes differed in expression along the rostral-to-caudal hierarchy formed by these 3 nodes. Moreover, pathway analysis revealed enrichment of genes in V1 related to circadian rhythms and in DLPFC of genes involved in synaptic plasticity. Overall, these results show robust regional differences in the transcriptome of layer 3 PNs, which likely contribute to regional specialization in their morphological and physiological features and thus in their functional contributions to vsWM.


Asunto(s)
Memoria a Corto Plazo , Corteza Visual , Humanos , Memoria a Corto Plazo/fisiología , Corteza Visual/fisiología , Corteza Prefrontal/fisiología , Células Piramidales/fisiología , Expresión Génica
6.
PLoS Genet ; 16(8): e1008930, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32760061

RESUMEN

Genomic imprinting is a parent-of-origin dependent phenomenon that restricts transcription to predominantly one parental allele. Since the discovery of the first long noncoding RNA (lncRNA), which notably was an imprinted lncRNA, a body of knowledge has demonstrated pivotal roles for imprinted lncRNAs in regulating parental-specific expression of neighboring imprinted genes. In this Review, we will discuss the multiple functionalities attributed to lncRNAs and how they regulate imprinted gene expression. We also raise unresolved questions about imprinted lncRNA function, which may lead to new avenues of investigation. This Review is dedicated to the memory of Denise Barlow, a giant in the field of genomic imprinting and functional lncRNAs. With her passion for understanding the inner workings of science, her indominable spirit and her consummate curiosity, Denise blazed a path of scientific investigation that made many seminal contributions to genomic imprinting and the wider field of epigenetic regulation, in addition to inspiring future generations of scientists.


Asunto(s)
Impresión Genómica , ARN Largo no Codificante/genética , Animales , Humanos , ARN Largo no Codificante/metabolismo
7.
Cancer ; 128(11): 2182-2192, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35363879

RESUMEN

BACKGROUND: Peptide receptor radionuclide therapy (PRRT) has shown favorable results in neuroendocrine tumors (NETs). Long-term safety and efficacy data for 177 Lu-octreotate PRRT, particularly in combination with chemotherapy, is lacking. METHODS: The authors conducted a retrospective review of the long-term toxicity and survival outcomes of 104 patients with advanced NETs treated on 4 phase 2 clinical trials with Lutetium-177-octreotate (177 Lu-octreotate) PRRT, mostly in combination with chemotherapy. Median follow-up was 68 months, which represents the longest follow-up study of 177 Lu-octreotate PRRT for NETs to date. RESULTS: Median progression-free survival (PFS) was 37 months, and median overall survival (OS) was 71 months. Five- and 10-year OS were 62% and 29%, and 5- and 10-year PFS were 36% and 21%, respectively, demonstrating 177 Lu-octreotate can provide durable responses. PRRT was well tolerated with 1.9% of patients developing chronic renal impairment and 1% of patients developing long-term thrombocytopenia. Interestingly, there was a relatively high rate of myelodysplasia (MDS)/leukemia (6.7%), possibly attributable to the longer follow-up (with all except 1 case occurring more than 4 years after PRRT treatment) or to the addition of concurrent chemotherapy. CONCLUSIONS: Lutetium-177-Octreotate PRRT remains an efficacious and well tolerated treatment in long-term follow-up. For clinicians deciding on the timing of PRRT for individual patients, the 6.7% long-term risk of MDS/leukemia needs to be balanced against the 21% PFS at 10 years.


Asunto(s)
Leucemia , Tumores Neuroendocrinos , Compuestos Organometálicos , Estudios de Seguimiento , Humanos , Leucemia/tratamiento farmacológico , Tumores Neuroendocrinos/tratamiento farmacológico , Tumores Neuroendocrinos/radioterapia , Octreótido/efectos adversos , Compuestos Organometálicos/efectos adversos , Radioisótopos/efectos adversos
8.
Lancet ; 397(10276): 797-804, 2021 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-33581798

RESUMEN

BACKGROUND: Lutetium-177 [177Lu]Lu-PSMA-617 is a radiolabelled small molecule that delivers ß radiation to cells expressing prostate-specific membrane antigen (PSMA), with activity and safety in patients with metastatic castration-resistant prostate cancer. We aimed to compare [177Lu]Lu-PSMA-617 with cabazitaxel in patients with metastatic castration-resistant prostate cancer. METHODS: We did this multicentre, unblinded, randomised phase 2 trial at 11 centres in Australia. We recruited men with metastatic castration-resistant prostate cancer for whom cabazitaxel was considered the next appropriate standard treatment. Participants were required to have adequate renal, haematological, and liver function, and an Eastern Cooperative Oncology Group performance status of 0-2. Previous treatment with androgen receptor-directed therapy was allowed. Men underwent gallium-68 [68Ga]Ga-PSMA-11 and 2-flourine-18[18F]fluoro-2-deoxy-D-glucose (FDG) PET-CT scans. PET eligibility criteria for the trial were PSMA-positive disease, and no sites of metastatic disease with discordant FDG-positive and PSMA-negative findings. Men were randomly assigned (1:1) to [177Lu]Lu-PSMA-617 (6·0-8·5 GBq intravenously every 6 weeks for up to six cycles) or cabazitaxel (20 mg/m2 intravenously every 3 weeks for up to ten cycles). The primary endpoint was prostate-specific antigen (PSA) response defined by a reduction of at least 50% from baseline. This trial is registered with ClinicalTrials.gov, NCT03392428. FINDINGS: Between Feb 6, 2018, and Sept 3, 2019, we screened 291 men, of whom 200 were eligible on PET imaging. Study treatment was received by 98 (99%) of 99 men randomly assigned to [177Lu]Lu-PSMA-617 versus 85 (84%) of 101 randomly assigned to cabazitaxel. PSA responses were more frequent among men in the [177Lu]Lu-PSMA-617 group than in the cabazitaxel group (65 vs 37 PSA responses; 66% vs 37% by intention to treat; difference 29% (95% CI 16-42; p<0·0001; and 66% vs 44% by treatment received; difference 23% [9-37]; p=0·0016). Grade 3-4 adverse events occurred in 32 (33%) of 98 men in the [177Lu]Lu-PSMA-617 group versus 45 (53%) of 85 men in the cabazitaxel group. No deaths were attributed to [177Lu]Lu-PSMA-617. INTERPRETATION: [177Lu]Lu-PSMA-617 compared with cabazitaxel in men with metastatic castration-resistant prostate cancer led to a higher PSA response and fewer grade 3 or 4 adverse events. [177Lu]Lu-PSMA-617 is a new effective class of therapy and a potential alternative to cabazitaxel. FUNDING: Prostate Cancer Foundation of Australia, Endocyte (a Novartis company), Australian Nuclear Science and Technology Organization, Movember, The Distinguished Gentleman's Ride, It's a Bloke Thing, and CAN4CANCER.


Asunto(s)
Dipéptidos/uso terapéutico , Compuestos Heterocíclicos con 1 Anillo/uso terapéutico , Lutecio/uso terapéutico , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Radioisótopos/uso terapéutico , Taxoides/uso terapéutico , Administración Intravenosa , Anciano , Antígenos de Superficie/genética , Glutamato Carboxipeptidasa II/genética , Humanos , Masculino , Tomografía Computarizada por Tomografía de Emisión de Positrones , Antígeno Prostático Específico/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/sangre , Neoplasias de la Próstata Resistentes a la Castración/radioterapia , Resultado del Tratamiento
9.
BJU Int ; 130 Suppl 3: 23-31, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35365966

RESUMEN

OBJECTIVES: To determine the effectiveness of technetium-99m (99m Tc)-sestamibi single-photon emission computerised tomography/computerised tomography (SPECT/CT) in distinguishing between malignant and benign renal lesions. PATIENTS AND METHODS: Between June 2018 and October 2020 all patients with new indeterminate small renal masses (SRMs) underwent 99m Tc-sestamibi renal SPECT/CT before biopsy or surgery. The accuracy of 99m Tc-sestamibi imaging diagnoses was assessed against histopathology. Receiver operating characteristic (ROC) analysis was used to determine the optimum cut-off for the tumour:normal uptake ratio. Logistic regression was used to determine if quantitative analysis significantly added to visual interpretation alone. RESULTS: A total of 74 patients with SRMs were investigated with 99m Tc-sestamibi SPECT/CT. The SPECT/CT correctly identified 49 malignant tumours and 11 benign tumours, resulting in a sensitivity of 0.89 (95% confidence interval [CI] 0.77-0.95) and a specificity of 0.73 (95% CI 0.45-0.91). The ROC analysis of uptake ratios demonstrated that a tumour:normal uptake ratio of 0.41 provided optimal diagnostic accuracy (sensitivity 0.81, specificity 0.88, area under the curve 0.883 [95% CI 0.794-0.971]). The uptake ratio was also highly significant in excluding malignancy on univariate logistic regression analysis whereby the higher the uptake ratio, the lower the chances were for malignancy (odds ratio 0.009, 95% CI 0.001-0.118, P < 0.001). However, this did not improve diagnostic accuracy when compared to visual interpretation alone. CONCLUSION: 99m Tc-sestamibi SPECT/CT is a non-invasive technique with good accuracy in determining if a SRM is benign or malignant.


Asunto(s)
Radiofármacos , Tecnecio Tc 99m Sestamibi , Humanos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada por Rayos X , Sensibilidad y Especificidad
10.
J Nucl Cardiol ; 29(4): 1855-1866, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-33825140

RESUMEN

BACKGROUND: There is currently no treatment for attenuating progression of arterial calcification. 18F-sodium fluoride positron emission tomography (18F-NaF PET) locates regions of calcification activity. We tested whether vitamin-K1 or colchicine affected arterial calcification activity. METHODS: 154 patients with diabetes mellitus and coronary calcification, as detected using computed tomography (CT), were randomized to one of four treatment groups (placebo/placebo, vitamin-K1 [10 mg/day]/placebo, colchicine [0.5 mg/day]/placebo, vitamin-K1 [10 mg/day]/ colchicine [0.5 mg/day]) in a double-blind, placebo-controlled 2x2 factorial trial of three months duration. Change in coronary calcification activity was estimated as a change in coronary maximum tissue-to-background ratio (TBRmax) on 18F-NaF PET. RESULTS: 149 subjects completed follow-up (vitamin-K1: placebo = 73:76 and colchicine: placebo = 73:76). Neither vitamin-K1 nor colchicine had a statistically significant effect on the coronary TBRmax compared with placebo (mean difference for treatment groups 0·00 ± 0·16 and 0·01 ± 0·17, respectively, p > 0.05). There were no serious adverse effects reported with colchicine or vitamin-K1. CONCLUSIONS: In patients with type 2 diabetes, neither vitamin-K1 nor colchicine significantly decreases coronary calcification activity, as estimated by 18F-NaF PET, over a period of 3 months. CLINICAL TRIAL REGISTRATION: ACTRN12616000024448.


Asunto(s)
Colchicina , Diabetes Mellitus Tipo 2 , Calcificación Vascular , Vitamina K 1 , Colchicina/uso terapéutico , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Método Doble Ciego , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Fluoruro de Sodio , Calcificación Vascular/diagnóstico por imagen , Calcificación Vascular/tratamiento farmacológico , Vitaminas
11.
Anesth Analg ; 129(1): 294-300, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30855341

RESUMEN

Inadequate access to anesthesia and surgical services is often considered to be a problem of low- and middle-income countries. However, affluent nations, including Canada, Australia, and the United States, also face shortages of anesthesia and surgical care in rural and remote communities. Inadequate services often disproportionately affect indigenous populations. A lack of anesthesia care providers has been identified as a major contributing factor to the shortfall of surgical and obstetrical care in rural and remote areas of these countries. This report summarizes the challenges facing the provision of anesthesia services in rural and remote regions. The current landscape of anesthesia providers and their training is described. We also explore innovative strategies and emerging technologies that could better support physician-led anesthesia care teams working in rural and remote areas. Ultimately, we believe that it is the responsibility of specialist anesthesiologists and academic health sciences centers to facilitate access to high-quality care through partnership with other stakeholders. Professional medical organizations also play an important role in ensuring the quality of care and continuing professional development. Enhanced collaboration between academic anesthesiologists and other stakeholders is required to meet the challenge issued by the World Health Organization to ensure access to essential anesthesia and surgical services for all.


Asunto(s)
Anestesia , Prestación Integrada de Atención de Salud/organización & administración , Países Desarrollados , Accesibilidad a los Servicios de Salud/organización & administración , Disparidades en Atención de Salud/organización & administración , Seguridad del Paciente , Servicios de Salud Rural/organización & administración , Anestesia/efectos adversos , Anestesia/economía , Anestesiólogos/organización & administración , Prestación Integrada de Atención de Salud/economía , Países Desarrollados/economía , Accesibilidad a los Servicios de Salud/economía , Disparidades en Atención de Salud/economía , Humanos , Liderazgo , Grupo de Atención al Paciente/organización & administración , Seguridad del Paciente/economía , Rol del Médico , Factores de Riesgo , Servicios de Salud Rural/economía
12.
Phytopathology ; 108(6): 702-710, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29318913

RESUMEN

Hypovirus-infected Cryphonectria parasitica strains were introduced in a large stand of American chestnut (>4,000 individuals) in western Wisconsin (USA) to evaluate whether hypoviruses can serve as biological control agents. They were deployed by treating cankers from 1992 to 1997 and again from 2004 to 2014. After 17 years of hypovirus introductions within an area of the stand with the longest history of disease, isolation of hypovirus-infected strains increased from 55% in 1994 to 86% in 2014 from cankers that were treated. During the same period, isolation from cankers that arose on trees with treated cankers increased from 29 to 72% and from 15 to 84% for cankers on nearby trees that received no treatment. Tree survivorship over the 23-year study period for trees with treated cankers was 51% compared with 31% for trees that were not treated. Introduction of hypovirus has resulted in the regrowth of the crowns of many large-diameter trees. Putative recovery of American chestnut in this stand provides evidence that prolonged hypovirus treatment can act as a biological control when limited numbers of vegetative compatibility types of C. parasitica exist.


Asunto(s)
Ascomicetos/virología , Fagaceae/microbiología , Virus Fúngicos/fisiología , Antibiosis , Ascomicetos/fisiología , Enfermedades de las Plantas/prevención & control , Factores de Tiempo , Wisconsin
13.
Can Fam Physician ; 64(3): e108-e114, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29540399

RESUMEN

OBJECTIVE: To investigate whether the fetal fibronectin assay would be useful for determining if a woman was close to a term delivery. If effective, this test would allow parturient women to stay in their communities longer. DESIGN: This feasibility study used a prospective cohort design to examine the negative predictive value of the fetal fibronectin test at term. SETTING: Iqaluit, NU. PARTICIPANTS: A total of 30 parturient women from rural and isolated communities in Nunavut. INTERVENTION: Starting at 36 weeks' gestation, women were tested every 2 days, and after 39 weeks this increased to every day until labour. MAIN OUTCOME MEASURES: The negative predictive value of the fetal fibronectin test was assessed. RESULTS: Women were no more likely to give birth at 7 or more days after their last negative fetal fibronectin test result relative to their likelihood of giving birth at 6 or fewer days after their last negative test result. Hence, the presence of fetal fibronectin in cervical secretion did not predict term delivery. CONCLUSION: This project indicated that the fetal fibronectin test did not have adequate sensitivity or specificity as a diagnostic measure to predict a delay of labour at term.


Asunto(s)
Fibronectinas/análisis , Edad Gestacional , Inicio del Trabajo de Parto/etnología , Cuello del Útero/química , Femenino , Humanos , Nunavut , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Población Rural
15.
J Pharmacol Exp Ther ; 362(2): 254-262, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28533287

RESUMEN

Prescription opioids are a mainstay in the treatment of acute moderate to severe pain. However, chronic use leads to a host of adverse consequences including tolerance and opioid-induced hyperalgesia (OIH), leading to more complex treatment regimens and diminished patient compliance. Patients with OIH paradoxically experience exaggerated nociceptive responses instead of pain reduction after chronic opioid usage. The development of OIH and tolerance tend to occur simultaneously and, thus, present a challenge when studying the molecular mechanisms driving each phenomenon. We tested the hypothesis that a G protein-biased µ-opioid peptide receptor (MOPR) agonist would not induce symptoms of OIH, such as mechanical allodynia, following chronic administration. We observed that the development of opioid-induced mechanical allodynia (OIMA), a model of OIH, was absent in ß-arrestin1-/- and ß-arrestin2-/- mice in response to chronic administration of conventional opioids such as morphine, oxycodone and fentanyl, whereas tolerance developed independent of OIMA. In agreement with the ß-arrestin knockout mouse studies, chronic administration of TRV0109101, a G protein-biased MOPR ligand and structural analog of oliceridine, did not promote the development of OIMA but did result in drug tolerance. Interestingly, following induction of OIMA by morphine or fentanyl, TRV0109101 was able to rapidly reverse allodynia. These observations establish a role for ß-arrestins in the development of OIH, independent of tolerance, and suggest that the use of G protein-biased MOPR ligands, such as oliceridine and TRV0109101, may be an effective therapeutic avenue for managing chronic pain with reduced propensity for opioid-induced hyperalgesia.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Proteínas de Unión al GTP/agonistas , Hiperalgesia/tratamiento farmacológico , Dimensión del Dolor/efectos de los fármacos , Receptores Opioides mu/agonistas , Animales , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Proteínas de Unión al GTP/fisiología , Células HEK293 , Humanos , Hiperalgesia/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Dimensión del Dolor/métodos , Receptores Opioides mu/fisiología
16.
J Cell Physiol ; 231(12): 2768-78, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27017909

RESUMEN

Proper regulation of cytosolic Ca(2+) is critical for pancreatic acinar cell function. Disruptions in normal Ca(2+) concentrations affect numerous cellular functions and are associated with pancreatitis. Membrane pumps and channels regulate cytosolic Ca(2+) homeostasis by promoting rapid Ca(2+) movement. Determining how expression of Ca(2+) modulators is regulated and the cellular alterations that occur upon changes in expression can provide insight into initiating events of pancreatitis. The goal of this study was to delineate the gene structure and regulation of a novel pancreas-specific isoform for Secretory Pathway Ca(2+) ATPase 2 (termed SPCA2C), which is encoded from the Atp2c2 gene. Using Next Generation Sequencing of RNA (RNA-seq), chromatin immunoprecipitation for epigenetic modifications and promoter-reporter assays, a novel transcriptional start site was identified that promotes expression of a transcript containing the last four exons of the Atp2c2 gene (Atp2c2c). This region was enriched for epigenetic marks and pancreatic transcription factors that promote gene activation. Promoter activity for regions upstream of the ATG codon in Atp2c2's 24th exon was observed in vitro but not in in vivo. Translation from this ATG encodes a protein aligned with the carboxy terminal of SPCA2. Functional analysis in HEK 293A cells indicates a unique role for SPCA2C in increasing cytosolic Ca(2+) . RNA analysis indicates that the decreased Atp2c2c expression observed early in experimental pancreatitis reflects a global molecular response of acinar cells to reduce cytosolic Ca(2+) levels. Combined, these results suggest SPCA2C affects Ca(2+) homeostasis in pancreatic acinar cells in a unique fashion relative to other Ca(2+) ATPases. J. Cell. Physiol. 231: 2768-2778, 2016. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Células Acinares/metabolismo , ATPasas Transportadoras de Calcio/genética , Páncreas/patología , Sitio de Iniciación de la Transcripción , Transcripción Genética , Células Acinares/patología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Calcio/metabolismo , ATPasas Transportadoras de Calcio/química , ATPasas Transportadoras de Calcio/metabolismo , Ceruletida , Epigénesis Genética , Exones/genética , Femenino , Genoma , Células HEK293 , Histonas/metabolismo , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Transgénicos , Pancreatitis/genética , Pancreatitis/patología , Regiones Promotoras Genéticas , ARN Mensajero/genética , ARN Mensajero/metabolismo
17.
Biochem Cell Biol ; 94(1): 43-55, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26222733

RESUMEN

Recently, many advancements in genome-wide chromatin topology and nuclear architecture have unveiled the complex and hidden world of the nucleus, where chromatin is organized into discrete neighbourhoods with coordinated gene expression. This includes the active and inactive X chromosomes. Using X chromosome inactivation as a working model, we utilized publicly available datasets together with a literature review to gain insight into topologically associated domains, lamin-associated domains, nucleolar-associating domains, scaffold/matrix attachment regions, and nucleoporin-associated chromatin and their role in regulating monoallelic expression. Furthermore, we comprehensively review for the first time the role of chromatin topology and nuclear architecture in the regulation of genomic imprinting. We propose that chromatin topology and nuclear architecture are important regulatory mechanisms for directing gene expression within imprinted domains. Furthermore, we predict that dynamic changes in chromatin topology and nuclear architecture play roles in tissue-specific imprint domain regulation during early development and differentiation.


Asunto(s)
Núcleo Celular/química , Cromatina/química , Impresión Genómica , Inactivación del Cromosoma X , Animales , Diferenciación Celular , Núcleo Celular/metabolismo , Cromatina/metabolismo , Humanos , Ratones , Proteínas de Complejo Poro Nuclear/metabolismo , ARN Largo no Codificante/química , ARN Largo no Codificante/metabolismo
18.
Biol Reprod ; 95(3): 61, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27465133

RESUMEN

In mice, assisted reproductive technologies (ARTs) applied during gametogenesis and preimplantation development can result in disruption of genomic imprinting. In humans, these technologies and/or subfertility have been linked to perturbations in genomic imprinting. To understand how ARTs and infertility affect DNA methylation, it is important to understand DNA methylation dynamics and the role of regulatory factors at these critical stages. Recent genome studies performed using mouse and human gametes and preimplantation embryos have shed light onto these processes. Here, we comprehensively review the current state of knowledge regarding global and imprinted DNA methylation programming in the mouse and human. Available data highlight striking similarities in mouse and human DNA methylation dynamics during gamete and preimplantation development. Just as fascinating, these studies have revealed sex-, gene-, and allele-specific differences in DNA methylation programming, warranting future investigation to untangle the complex regulation of DNA methylation dynamics during gamete and preimplantation development.


Asunto(s)
Blastocisto/metabolismo , Metilación de ADN , Desarrollo Embrionario/fisiología , Impresión Genómica , Animales , Femenino , Humanos , Ratones , Técnicas Reproductivas Asistidas
19.
Appl Environ Microbiol ; 81(17): 5736-42, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-26070681

RESUMEN

Chestnut blight is a devastating disease of Castanea spp. Mycoviruses that reduce virulence (hypovirulence) of the causative agent, Cryphonectria parasitica, can be used to manage chestnut blight. However, vegetative incompatibility (vic) barriers that restrict anastomosis-mediated virus transmission hamper hypovirulence efficacy. In order to effectively determine the vegetative incompatibility genetic structure of C. parasitica field populations, we have designed PCR primer sets that selectively amplify and distinguish alleles for each of the six known diallelic C. parasitica vic genetic loci. PCR assay results were validated using a panel of 64 European tester strains with genetically determined vic genotypes. Analysis of 116 C. parasitica isolates collected from five locations in the eastern United States revealed 39 unique vic genotypes and generally good agreement between PCR and tester strain coculturing assays in terms of vic diversity and genotyping. However, incongruences were observed for isolates from multiple locations and suggested that the coculturing assay can overestimate diversity at the six known vic loci. The availability of molecular tools for rapid and precise vic genotyping significantly improves the ability to predict and evaluate the efficacy of hypovirulence and related management strategies.


Asunto(s)
Ascomicetos/genética , Ascomicetos/aislamiento & purificación , Fagaceae/microbiología , Enfermedades de las Plantas/microbiología , Alelos , Ascomicetos/metabolismo , Ascomicetos/patogenicidad , Cartilla de ADN/genética , Sitios Genéticos , Genotipo , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Reacción en Cadena de la Polimerasa , Virulencia
20.
J Obstet Gynaecol Can ; 37(5): 451-63, 2015 05.
Artículo en Inglés | MEDLINE | ID: mdl-26168107

RESUMEN

This document has been archived because it contains outdated information. It should not be consulted for clinical use, but for historical research only. Please visit the journal website for the most recent guidelines.


Ce document a été archivé, car il contient des informations périmées. Il ne devrait pas être consulté pour un usage clinique, mais uniquement pour des recherches historiques. Veuillez consulter le site web du journal pour les directives les plus récentes.


Asunto(s)
Pruebas Genéticas , Diagnóstico Preimplantación , Biopsia , Canadá , Análisis Citogenético , Embrión de Mamíferos/patología , Femenino , Asesoramiento Genético , Enfermedades Genéticas Congénitas/diagnóstico , Humanos , Embarazo , Diagnóstico Preimplantación/métodos , Técnicas Reproductivas Asistidas , Factores de Riesgo , Translocación Genética
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