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1.
Artigo em Inglês | MEDLINE | ID: mdl-38670121

RESUMO

Congenital nasolacrimal duct obstruction (CNLDO) is the most common cause of epiphora in the first year of life. In addition to conservative therapy, there are several invasive methods available. The aim of this retrospective study was to conduct a long-term follow-up of bicanalicular lacrimal duct intubation as the primary intervention in a large cohort of patients with CNLDO. The electronic medical records of 487 patients with CNLDO who underwent bicanalicular tube intubation were reviewed. To determine the long-term outcomes, a telephone interview was conducted. A total of 328 eyes of 235 patients were included in the study. The median average follow-up period was 6.67 (5.58 - 8.67) years. At the time of the survey, 218 patients (92.8%) were symptom free. Mean patient satisfaction with surgical outcome was 10/10. To our knowledge, this study provides the longest follow-up of the largest patient cohort in the literature consisting of patients who underwent probing with bicanalicular lacrimal silicone tube intubation as a primary intervention for CNLDO. This study showed a high long-term postoperative success rate, with high postoperative satisfaction, few complications, and a low need for reintervention.

2.
BMC Genomics ; 24(1): 237, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37142951

RESUMO

BACKGROUND: Microsporidia are diverse spore forming, fungal-related obligate intracellular pathogens infecting a wide range of hosts. This diversity is reflected at the genome level with sizes varying by an order of magnitude, ranging from less than 3 Mb in Encephalitozoon species (the smallest known in eukaryotes) to more than 50 Mb in Edhazardia spp. As a paradigm of genome reduction in eukaryotes, the small Encephalitozoon genomes have attracted much attention with investigations revealing gene dense, repeat- and intron-poor genomes characterized by a thorough pruning of molecular functions no longer relevant to their obligate intracellular lifestyle. However, because no Encephalitozoon genome has been sequenced from telomere-to-telomere and since no methylation data is available for these species, our understanding of their overall genetic and epigenetic architectures is incomplete. METHODS: In this study, we sequenced the complete genomes from telomere-to-telomere of three human-infecting Encephalitozoon spp. -E. intestinalis ATCC 50506, E. hellem ATCC 50604 and E. cuniculi ATCC 50602- using short and long read platforms and leveraged the data generated as part of the sequencing process to investigate the presence of epigenetic markers in these genomes. We also used a mixture of sequence- and structure-based computational approaches, including protein structure prediction, to help identify which Encephalitozoon proteins are involved in telomere maintenance, epigenetic regulation, and heterochromatin formation. RESULTS: The Encephalitozoon chromosomes were found capped by TTAGG 5-mer telomeric repeats followed by telomere associated repeat elements (TAREs) flanking hypermethylated ribosomal RNA (rRNA) gene loci featuring 5-methylcytosines (5mC) and 5-hemimethylcytosines (5hmC), themselves followed by lesser methylated subtelomeres and hypomethylated chromosome cores. Strong nucleotide biases were identified between the telomeres/subtelomeres and chromosome cores with significant changes in GC/AT, GT/AC and GA/CT contents. The presence of several genes coding for proteins essential to telomere maintenance, epigenetic regulation, and heterochromatin formation was further confirmed in the Encephalitozoon genomes. CONCLUSION: Altogether, our results strongly support the subtelomeres as sites of heterochromatin formation in Encephalitozoon genomes and further suggest that these species might shutdown their energy-consuming ribosomal machinery while dormant as spores by silencing of the rRNA genes using both 5mC/5hmC methylation and facultative heterochromatin formation at these loci.


Assuntos
Encephalitozoon , Microsporídios , Humanos , Encephalitozoon/genética , Epigênese Genética , Heterocromatina/genética , Genoma Fúngico , Telômero/genética
3.
Eur Radiol ; 33(12): 8974-8985, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37368108

RESUMO

OBJECTIVES: Image-based detection of intralesional fat in focal liver lesions has been established in diagnostic guidelines as a feature indicative of hepatocellular carcinoma (HCC) and associated with a favorable prognosis. Given recent advances in MRI-based fat quantification techniques, we investigated a possible relationship between intralesional fat content and histologic tumor grade in steatotic HCCs. METHODS: Patients with histopathologically confirmed HCC and prior MRI with proton density fat fraction (PDFF) mapping were retrospectively identified. Intralesional fat of HCCs was assessed using an ROI-based analysis and the median fat fraction of steatotic HCCs was compared between tumor grades G1-3 with non-parametric testing. ROC analysis was performed in case of statistically significant differences (p < 0.05). Subgroup analyses were conducted for patients with/without liver steatosis and with/without liver cirrhosis. RESULTS: A total of 57 patients with steatotic HCCs (62 lesions) were eligible for analysis. The median fat fraction was significantly higher for G1 lesions (median [interquartile range], 7.9% [6.0─10.7%]) than for G2 (4.4% [3.2─6.6%]; p = .001) and G3 lesions (4.7% [2.8─7.8%]; p = .036). PDFF was a good discriminator between G1 and G2/3 lesions (AUC .81; cut-off 5.8%, sensitivity 83%, specificity 68%) with comparable results in patients with liver cirrhosis. In patients with liver steatosis, intralesional fat content was higher than in the overall sample, with PDFF performing better in distinguishing between G1 and G2/3 lesions (AUC .92; cut-off 8.8%, sensitivity 83%, specificity 91%). CONCLUSIONS: Quantification of intralesional fat using MRI PDFF mapping allows distinction between well- and less-differentiated steatotic HCCs. CLINICAL RELEVANCE: PDFF mapping may help optimize precision medicine as a tool for tumor grade assessment in steatotic HCCs. Further investigation of intratumoral fat content as a potential prognostic indicator of treatment response is encouraged. KEY POINTS: • MRI proton density fat fraction mapping enables distinction between well- (G1) and less- (G2 and G3) differentiated steatotic hepatocellular carcinomas. • In a retrospective single-center study with 62 histologically proven steatotic hepatocellular carcinomas, G1 tumors showed a higher intralesional fat content than G2 and G3 tumors (7.9% vs. 4.4% and 4.7%; p = .004). • In liver steatosis, MRI proton density fat fraction mapping was an even better discriminator between G1 and G2/G3 steatotic hepatocellular carcinomas.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Estudos Retrospectivos , Prótons , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Cirrose Hepática/patologia
4.
Graefes Arch Clin Exp Ophthalmol ; 261(5): 1433-1442, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36580078

RESUMO

PURPOSE: Rheumatoid arthritis (RA) is the most common inflammatory joint disease, and hydroxychloroquine (HCQ) is an established treatment. The extent to which HCQ impacts ocular microvascular vessel density (VD) in patients with RA without evidence of HCQ retinopathy has not yet been conclusively clarified. The main aim of this study was to evaluate VD measured by optical coherence tomography angiography (OCTA) in patients with RA treated with HCQ. METHODS: The VD data of the 3 × 3 mm OCT angiogram (RTVue XR Avanti, Optovue Inc., Fremont, California, USA) as well as the retinal thickness (RT) data of patients with RA (n = 30) and healthy controls (n = 30) were extracted and analyzed. The study group was further divided into patients undergoing HCQ treatment for > 5 years (high-risk-group) and < 5 years (low-risk group). RESULTS: Patients with RA showed no evidence of VD reduction compared to the control group in all obtained regions (p > 0.05). Correlation analysis revealed no dependency between VD, RT, and HCQ therapy duration or cumulative HCQ dose (p > 0.05). High-risk patients showed a decreased VD in the superficial quadrant of the superficial capillary plexus compared to low-risk-patients (p = 0.022). Whole-en-face RT was reduced in the high-risk group compared to the control group (p = 0.019). CONCLUSION: Our study showed no evidence that HCQ diminishes VD in patients with RA without HCQ retinopathy measured by OCTA. However, RA patients with a long duration of therapy showed a significantly reduced RT. Our results suggest that quantitative VD analysis by OCTA may not be suitable for early detection of HCQ retinopathy and that the focus on detecting early HCQ retinopathy should be on intensive and sequential OCT diagnostics.


Assuntos
Artrite Reumatoide , Doenças Retinianas , Humanos , Hidroxicloroquina/efeitos adversos , Vasos Retinianos , Densidade Microvascular , Angiofluoresceinografia/métodos , Doenças Retinianas/induzido quimicamente , Doenças Retinianas/diagnóstico , Doenças Retinianas/tratamento farmacológico , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Tomografia de Coerência Óptica/métodos
5.
Retina ; 43(9): 1525-1533, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37184510

RESUMO

PURPOSE: Recent studies have questioned the traditional view, which regards Coats disease as a strictly unilateral entity. Applying optical coherence tomography angiography, this prospective, monocentric study investigates quantitative capillary changes of the macula associated with Coats disease. METHODS: Twenty-four eyes (4 untreated, 8 pre-treated) of 12 patients with stage 2 Coats disease (age range: 9-61 years) and 15 eyes of healthy, age-matched controls from the University of Muenster Medical Center, Germany received macular optical coherence tomography angiography measurements of the superficial, deep, and choriocapillary capillary plexus. Flow density and parameters related to the foveal avascular zone were compared between Coats eyes and fellow eyes, and between fellow eyes and control eyes. Additional subanalyses investigated changes based on disease stage. RESULTS: Flow density did not differ between fellow eyes of Coats disease patients and control eyes in any of the parameters investigated. Comparison of Coats eyes to their respective fellow eyes revealed Coats disease to be associated with lower flow density in superficial, deep, and choriocapillary capillary plexus regions, irrespective of disease stage (all P < 0.03). There were no noticeable differences regarding the size or symmetry of the foveal avascular zone. CONCLUSION: In light of the recent discussion around the unilateral character of Coats disease, this trial provides evidence against a bilateral presentation of vascular changes in the macula.


Assuntos
Telangiectasia Retiniana , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Telangiectasia Retiniana/diagnóstico , Fóvea Central/irrigação sanguínea , Vasos Retinianos , Angiofluoresceinografia/métodos , Tomografia de Coerência Óptica/métodos , Estudos Prospectivos
6.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-37678401

RESUMO

There are only about 100 case reports on the Acute Idiopathic Blind Spot Enlargement Syndrome (AIBSES). This is characterised by the eponymous visual field loss in the blind spot area, acute onset photopsia, and funduscopically little or no change in the optic disc area, with conspicuous outer retinal bands on optical coherence tomography (OCT). Typical is the unilateral occurrence. Predominantly young women are affected. While previous reviews of AIBSES either predate the introduction of OCT or focus on differentiation from potentially related outer retinal conditions (e.g., multiple evanescent white dot syndrome and acute zonal occult outer retinopathy), the present review will concentrate on the current perspective and treatment strategies that have been developed and will aim to help increase awareness. Since the first description of AIBSES in the late 1980s, the introduction of OCT has simplified the diagnosis and characterisation of AIBSES as a disease of the outer retina. Nevertheless, misdiagnosis remains common in the spectrum of optic neuritis, as AIBSES may be ignored in differential diagnosis.

7.
Chembiochem ; 23(15): e202200006, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35416400

RESUMO

In the past three decades, in vitro systematic evolution of ligands by exponential enrichment (SELEX) has yielded many aptamers for translational applications in both research and clinical settings. Despite their promise as an alternative to antibodies, the low success rate of SELEX (∼30 %) has been a major bottleneck that hampers the further development of aptamers. One hurdle is the lack of chemical diversity in nucleic acids. To address this, the aptamer chemical repertoire has been extended by introducing exotic chemical groups, which provide novel binding functionalities. This review will focus on how modified aptamers can be selected and evolved, with illustration of some successful examples. In particular, unique chemistries are exemplified. Various strategies of incorporating modified building blocks into the standard SELEX protocol are highlighted, with a comparison of the differences between pre-SELEX and post-SELEX modifications. Nucleic acid aptamers with extended functionality evolved from non-natural chemistries will open up new vistas for function and application of nucleic acids.


Assuntos
Aptâmeros de Nucleotídeos , Ácidos Nucleicos , Anticorpos , Aptâmeros de Nucleotídeos/metabolismo , Ligantes , Técnica de Seleção de Aptâmeros/métodos
8.
BMC Pregnancy Childbirth ; 22(1): 132, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35172775

RESUMO

BACKGROUND: The rates of exclusive breastfeeding at 6 months in Spain are far from recommended by the World Health Organization, which is 50% by 2025. Evidence of the effectiveness of group interventions in late postpartum is limited. The objective of this study was to evaluate the effectiveness of the PROLACT group educational intervention for increasing the proportion of mother-child dyads with exclusive breastfeeding at 6 months compared to the usual practice in primary care. METHOD: Multicentre cluster randomized clinical trial. A total of 434 mother-child dyads who breastfed exclusively in the first 4 weeks of the children's life and agreed to participate were included. The main outcome was exclusive breastfeeding at 6 months. Secondary variables were type of breastfeeding, reasons for abandonment, degree of adherence and satisfaction with the intervention. To study the effectiveness, the difference in the proportions of dyads with exclusive breastfeeding at 6 months was calculated, and the relative risk (RR) and number needed to treat (NNT) were calculated with their 95% CIs. To study the factors associated with the maintenance of exclusive breastfeeding at 6 months, a multilevel logistic regression model was fitted. All analyses were performed to intention to treat. RESULTS: The percentage of dyads with exclusive breastfeeding at 6 months was 22.4% in the intervention group and 8.8% in the control group. PROLACT intervention obtained an RR =2.53 (95% CI: 1.54-4.15) and an NNT = 7 (95%CI: 5-14). The factors associated with exclusive breastfeeding at 6 months were the PROLACT intervention, OR = 3.51 (95%CI: 1.55-7.93); age > 39 years, OR = 2.79 (95%CI: 1.02-7.6); previous breastfeeding experience, OR = 2.61 (95%CI: 1.29-5.29); income between 500 and 833.33 €, OR = 3.52 (95%CI 1.47-8.47).); planning to start work before the infant was 6 months old, OR = 0.35 (0.19-0.63) . CONCLUSIONS: The PROLACT intervention in primary care is more effective than the usual practice for maintaining exclusive breastfeeding at 6 months, and can therefore be considered evidence-based practice for implementation in standard practice. TRIAL REGISTRATION: The trial was registered with ClinicalTrials.gov under code number NCT01869920 (03/06/2013).


Assuntos
Aleitamento Materno , Educação em Saúde/métodos , Promoção da Saúde/métodos , Mães/educação , Cooperação do Paciente/estatística & dados numéricos , Avaliação de Programas e Projetos de Saúde , Adulto , Feminino , Guias como Assunto , Humanos , Atenção Primária à Saúde , Espanha
10.
Cell Physiol Biochem ; 54(2): 321-332, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32259418

RESUMO

BACKGROUND/AIMS: The cardiac current IKs is carried by the KCNQ1/KCNE1-channel complex. Genetic aberrations that affect the activity of KCNQ1/KCNE1 can lead to the Long QT Syndrome 1 and 5 and, thereby, to a predisposition to sudden cardiac death. This might be prevented by pharmacological modulation of KCNQ1/KCNE1. The prototypic KCNQ1/KCNE1 activator 4,4'-Diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) represents a candidate drug. Here, we study the mechanism of DIDS action on KCNQ1/KCNE1. METHODS: Channels were expressed in Xenopus oocytes and iPSC cardiomyocytes. The role of the central S6 region was investigated by alanin-screening of KCNQ1 residues 333-338. DIDS effects were measured by TEVC and MEA. RESULTS: DIDS-action is influenced by the presence of KCNE1 but not by KCNQ1/KCNE1 stochiometry. V334A produces a significant higher increase in current amplitude, whereas deactivation (slowdown) DIDS-sensitivity is affected by residues 334-338. CONCLUSION: We show that the central S6 region serves as a hub for allosteric channel activation by the drug and that DIDS shortens the pseudo QT interval in iPSC cardiomyocytes. The elucidation of the structural and mechanistic underpinnings of the DIDS action on KCNQ1/KCNE1 might allow for a targeted design of DIDS derivatives with improved potency and selectivity.


Assuntos
Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Potenciais de Ação/efeitos dos fármacos , Canal de Potássio KCNQ1/metabolismo , Miócitos Cardíacos/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/química , Regulação Alostérica , Animais , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Ativação do Canal Iônico/efeitos dos fármacos , Canal de Potássio KCNQ1/química , Canal de Potássio KCNQ1/genética , Modelos Moleculares , Mutação , Oócitos/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/química , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Domínios Proteicos , Xenopus laevis
11.
J Biol Chem ; 293(15): 5522-5531, 2018 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-29463678

RESUMO

The StARkin superfamily comprises proteins with steroidogenic acute regulatory protein-related lipid transfer (StART) domains that are implicated in intracellular, non-vesicular lipid transport. A new family of membrane-anchored StARkins was recently identified, including six members, Lam1-Lam6, in the yeast Saccharomyces cerevisiae. Lam1-Lam4 are anchored to the endoplasmic reticulum (ER) membrane at sites where the ER is tethered to the plasma membrane and proposed to be involved in sterol homeostasis in yeast. To better understand the biological roles of these proteins, we carried out a structure-function analysis of the second StARkin domain of Lam4, here termed Lam4S2. NMR experiments indicated that Lam4S2 undergoes specific conformational changes upon binding sterol, and fluorescence-based assays revealed that it catalyzes sterol transport between vesicle populations in vitro, exhibiting a preference for vesicles containing anionic lipids. Using such vesicles, we found that sterols are transported at a rate of ∼50 molecules per Lam4S2 per minute. Crystal structures of Lam4S2, with and without bound sterol, revealed a largely hydrophobic but surprisingly accessible sterol-binding pocket with the 3-OH group of the sterol oriented toward its base. Single or multiple alanine or aspartic acid replacements of conserved lysine residues in a basic patch on the surface of Lam4S2 near the likely sterol entry/egress site strongly attenuated sterol transport. Our results suggest that Lam4S2 engages anionic membranes via a basic surface patch, enabling "head-first" entry of sterol into the binding pocket followed by partial closure of the entryway. Reversal of these steps enables sterol egress.


Assuntos
Antiporters/química , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/química , Esteróis/química , Antiporters/genética , Antiporters/metabolismo , Transporte Biológico Ativo/fisiologia , Domínios Proteicos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Esteróis/metabolismo
12.
J Magn Reson Imaging ; 50(6): 1762-1772, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30980694

RESUMO

BACKGROUND: Chemical shift-encoding based water-fat MRI is an emerging method to noninvasively assess proton density fat fraction (PDFF), a promising quantitative imaging biomarker for estimating tissue fat concentration. However, in vivo validation of PDFF is still lacking for bone marrow applications. PURPOSE: To determine the accuracy and precision of MRI-determined vertebral bone marrow PDFF among different readers and across different field strengths and imager manufacturers. STUDY TYPE: Repeatability/reproducibility. SUBJECTS: Twenty-four adult volunteers underwent lumbar spine MRI with one 1.5T and two different 3.0T MR scanners from two vendors on the same day. FIELD STRENGTH/SEQUENCE: 1.5T and 3.0T/3D spoiled-gradient echo multipoint Dixon sequences. ASSESSMENT: Two independent readers measured intravertebral PDFF for the three most central slices of the L1-5 vertebral bodies. Single-voxel MR spectroscopy (MRS)-determined PDFF served as the reference standard for PDFF estimation. STATISTICAL TESTS: Accuracy and bias were assessed by Pearson correlation, linear regression analysis, and Bland-Altman plots. Repeatability and reproducibility were evaluated by Wilcoxon signed rank test, Friedman test, and coefficients of variation. Intraclass correlation coefficients were used to validate intra- and interreader as well as intraimager agreements. RESULTS: MRI-based PDFF estimates of lumbar bone marrow were highly correlated (r2 = 0.899) and accurate (mean bias, -0.6%) against the MRS-determined PDFF reference standard. PDFF showed high linearity (r2 = 0.972-0.978) and small mean bias (0.6-1.5%) with 95% limits of agreement within ±3.4% across field strengths, imaging platforms, and readers. Repeatability and reproducibility of PDFF were high, with the mean overall coefficient of variation being 0.86% and 2.77%, respectively. The overall intraclass correlation coefficient was 0.986 as a measure for an excellent interreader agreement. DATA CONCLUSION: MRI-based quantification of vertebral bone marrow PDFF is highly accurate, repeatable, and reproducible among readers, field strengths, and MRI platforms, indicating its robustness as a quantitative imaging biomarker for multicentric studies. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1762-1772.


Assuntos
Medula Óssea/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Espectroscopia de Prótons por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Vértebras Lombares/anatomia & histologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
14.
Eur Radiol ; 28(12): 5001-5009, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29858641

RESUMO

OBJECTIVES: To evaluate the diagnostic performance of proton density fat fraction (PDFF) magnetic resonance imaging (MRI) to differentiate between acute benign and neoplastic vertebral compression fractures (VCFs). METHODS: Fifty-seven consecutive patients with 46 acute benign and 41 malignant VCFs were prospectively enrolled in this institutional review board approved study and underwent routine clinical MRI with an additional six-echo modified Dixon sequence of the spine at a clinical 3.0-T scanner. All fractures were categorised as benign or malignant according to either direct bone biopsy or 6-month follow-up MRI. Intravertebral PDFF and PDFFratio (fracture PDFF/normal vertebrae PDFF) for benign and malignant VCFs were calculated using region-of-interest analysis and compared between both groups. Additional receiver operating characteristic and binary logistic regression analyses were performed. RESULTS: Both PDFF and PDFFratio of malignant VCFs were significantly lower compared to acute benign VCFs [PDFF, 3.48 ± 3.30% vs 23.99 ± 11.86% (p < 0.001); PDFFratio, 0.09 ± 0.09 vs 0.49 ± 0.24 (p < 0.001)]. The areas under the curve were 0.98 for PDFF and 0.97 for PDFFratio, yielding an accuracy of 96% and 95% for differentiating between acute benign and malignant VCFs. PDFF remained as the only imaging-based variable to independently differentiate between acute benign and malignant VCFs on multivariate analysis (odds ratio, 0.454; p = 0.005). CONCLUSIONS: Quantitative assessment of PDFF derived from modified Dixon water-fat MRI has high diagnostic accuracy for the differentiation of acute benign and malignant vertebral compression fractures. KEY POINTS: • Chemical-shift-encoding based water-fat MRI can reliably assess vertebral bone marrow PDFF • PDFF is significantly higher in acute benign than in malignant VCFs • PDFF provides high accuracy for differentiating acute benign from malignant VCFs.


Assuntos
Fraturas por Compressão/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Tecido Adiposo/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Ósseas Metabólicas/patologia , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Diagnóstico Diferencial , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Prótons , Curva ROC , Adulto Jovem
15.
Eur Radiol ; 28(6): 2397-2405, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29313118

RESUMO

OBJECTIVES: To investigate whether proton density fat fraction (PDFF) measurements using a six-echo modified Dixon sequence can help to differentiate between benign and malignant vertebral bone marrow lesions. METHODS: Sixty-six patients were prospectively enrolled in our study. In addition to conventional MRI at 3.0-Tesla including at least sagittal T2-weighted/spectral attenuated inversion recovery and T1-weighted sequences, all patients underwent a sagittal six-echo modified Dixon sequence of the spine. The mean PDFF was calculated using regions of interest and compared between vertebral lesions. A cut-off value of 6.40% in PDFF was determined by receiver operating characteristic curves and used to differentiate between malignant (< 6.40%) and benign (≥ 6.40%) vertebral lesions. RESULTS: There were 77 benign and 44 malignant lesions. The PDFF of malignant lesions was statistically significant lower in comparison with benign lesions (p < 0.001) and normal vertebral bone marrow (p < 0.001). The areas under the curves (AUC) were 0.97 for differentiating benign from malignant lesions (p < 0.001) and 0.95 for differentiating acute vertebral fractures from malignant lesions (p < 0.001). This yielded a diagnostic accuracy of 96% in the differentiation of both benign lesions and acute vertebral fractures from malignancy. CONCLUSION: PDFF derived from six-echo modified Dixon allows for differentiation between benign and malignant vertebral lesions with a high diagnostic accuracy. KEY POINTS: • Establishing a diagnosis of indeterminate vertebral lesions is a common clinical problem • Benign bone marrow processes may mimic the signal alterations observed in malignancy • PDFF differentiates between benign and malignant lesions with a high diagnostic accuracy • PDFF of non-neoplastic vertebral lesions is significantly higher than that of malignancy • PDFF from six-echo modified Dixon may help avoid potentially harmful bone biopsy.


Assuntos
Vértebras Cervicais/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Sacro/diagnóstico por imagem , Doenças da Coluna Vertebral/diagnóstico , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Tecido Adiposo/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prótons , Curva ROC , Adulto Jovem
16.
Eur Radiol ; 27(3): 966-975, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27271923

RESUMO

OBJECTIVES: To investigate whether quantifications of apparent diffusion coefficient (ADC) on diffusion-weighted imaging (DWI) can predict overall survival (OS) in patients with liver-predominant metastatic colorectal cancer (CRC) following selective internal radiation therapy with 90Yttrium-microspheres (SIRT). METHODS: Forty-four patients underwent DWI 19 ± 16 days before and 36 ± 10 days after SIRT. Tumour-size and intratumoral minimal ADC (minADC) values were measured for 132 liver metastases on baseline and follow-up DWI. Optimal functional imaging response to treatment was determined by receiver operating characteristics and defined as ≥22 % increase in post-therapeutic minADC. Survival analysis was performed with the Kaplan-Meier method and Cox-regression comparing various variables with potential impact on OS. RESULTS: Median OS was 8 months. The following parameters were significantly associated with median OS: optimal functional imaging response (18 vs. 5 months; p < 0.001), hepatic tumour burden <50 % (8 vs. 5 months; p = 0.018), Eastern Cooperative Oncology Group performance scale <1 (10 vs. 4 months; p = 0.012) and progressive disease according to Response and Evaluation Criteria in Solid Tumours (8 vs. 3 months; p = 0.001). On multivariate analysis, optimal functional imaging response and hepatic tumour burden remained independent predictors of OS. CONCLUSION: Functional imaging response assessment using minADC changes on DWI may predict survival in CRC shortly after SIRT. KEY POINTS: • Relative minADC changes may predict survival in liver-predominant metastatic colorectal cancer following SIRT • Intratumoral minADC changes by ≥22 % were best to predict an improved overall survival • Functional imaging response assessment is feasible before anatomic tumour-size changes occur • minADC changes might guide future therapy management in sequential lobar radioembolization approaches.


Assuntos
Braquiterapia/métodos , Neoplasias Colorretais/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Neoplasias Hepáticas/secundário , Masculino , Microesferas , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Radioisótopos de Ítrio/uso terapêutico
17.
BMC Med Educ ; 17(1): 221, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29157232

RESUMO

BACKGROUND: Interprofessional learning is gaining momentum in revolutionizing healthcare education. During the academic year 2015/16, seven undergraduate-entry health and social care programs from two universities in Hong Kong took part in an interprofessional education program. Based on considerations such as the large number of students involved and the need to incorporate adult learning principles, team-based learning was adopted as the pedagogy for the program, which was therefore called the interprofessional team-based learning program (IPTBL). The authors describe the development and implementation of the IPTBL program and evaluate the effectiveness of the program implementation. METHODS: Eight hundred and one students, who are predominantly Chinese, participated in the IPTBL. The quantitative design (a pretest-posttest experimental design) was utilized to examine the students' gains on their readiness to engage in interprofessional education (IPE). RESULTS: Three instructional units (IUs) were implemented, each around a clinical area which could engage students from complementary health and social care disciplines. Each IU followed a team-based learning (TBL) process: pre-class study, individual readiness assurance test, team readiness assurance test, appeal, feedback, and application exercise. An electronic platform was developed and was progressively introduced in the three IUs. The students' self-perceived attainment of the IPE learning outcomes was high. Across all four subscales of RIPLS, there was significant improvement in student's readiness to engage in interprofessional learning after the IPTBL. A number of challenges were identified: significant time involvement of the teachers, difficulty in matching students from different programs, difficulty in making IPTBL count towards a summative assessment score, difficulty in developing the LAMS platform, logistics difficulty in managing paper TBL, and inappropriateness of the venue. CONCLUSIONS: Despite some challenges in developing and implementing the IPTBL program, our experience showed that TBL is a viable pedagogy to be used in interprofessional education involving hundreds of students. The significant improvement in all four subscales of RIPLS showed the effects of the IPTBL program in preparing students for collaborative practice. Factors that contributed to the success of the use of TBL for IPE are discussed.


Assuntos
Ocupações em Saúde/educação , Relações Interprofissionais , Estudantes de Ciências da Saúde , Disciplinas das Ciências Biológicas/educação , Comportamento Cooperativo , Feminino , Hong Kong , Humanos , Masculino , Medicina Tradicional Chinesa , Serviço Social/educação , Universidades , Adulto Jovem
18.
Biochem Biophys Res Commun ; 479(4): 766-771, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27693781

RESUMO

Polyphosphate (polyP) is abundant in bone but its roles in signaling and control of gene expression remain unclear. Here, we investigate the effect of extracellular polyP on proliferation, migration, apoptosis, gene and protein expression in human osteoblast-like SaOS-2 cells. Extracellular polyP promoted SaOS-2 cell proliferation, increased rates of migration, inhibited apoptosis and stimulated the rapid phosphorylation of extracellular-signal-regulated kinase (ERK) directly through basic fibroblast growth factor receptor (bFGFR). cDNA microarray revealed that polyP induced significant upregulation of interleukin 11 (IL-11) at both RNA and protein levels.


Assuntos
Interleucina-11/genética , Interleucina-11/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Polifosfatos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Osteoblastos/citologia , Fosforilação , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Regulação para Cima/efeitos dos fármacos
19.
bioRxiv ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38798446

RESUMO

Investigating collinearity between chromosomes is often used in comparative genomics to help identify gene orthologs, pinpoint genes that might have been overlooked as part of annotation processes and/or perform various evolutionary inferences. Collinear segments, also known as syntenic blocks, can be inferred from sequence alignments and/or from the identification of genes arrayed in the same order and relative orientations between investigated genomes. To help perform these analyses and assess their outcomes, we built a simple pipeline called SYNY (for synteny) that implements the two distinct approaches and produces different visualizations. The SYNY pipeline was built with ease of use in mind and runs on modest hardware. The pipeline is written in Perl and Python and is available on GitHub (https://github.com/PombertLab/SYNY) under the permissive MIT license.

20.
Front Microbiol ; 15: 1347466, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468849

RESUMO

Pseudomonas aeruginosa is a common cause of urinary tract infections by strains that are often multidrug resistant, representing a major challenge to the world's health care system. This microorganism has a highly adaptable metabolism that allows it to colonize many environments, including the urinary tract. In this work, we have characterized the metabolic strategies used by stationary phase P. aeruginosa cells cultivated in urine-like media to understand the adaptations used by this microorganism to survive and produce disease. Our proteomics results show that cells rely on the Entner-Duodoroff pathway, pentose phosphate pathway, the Krebs cycle/ glyoxylate shunt and the aerobic oxidative phosphorylation to survive in urine-like media and other conditions. A deep characterization of the oxidative phosphorylation showed that the respiratory rate of stationary phase cells is increased 3-4 times compared to cells in the logarithmic phase of growth, indicating that the aerobic metabolism plays critical roles in the stationary phase of cells grown in urine like media. Moreover, the data show that respiratory complex III, succinate dehydrogenase and the NADH dehydrogenase NQR have important functions and could be used as targets to develop new antibiotics against this bacterium.

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