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1.
PLoS Pathog ; 17(2): e1009304, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33544760

RESUMEN

S. epidermidis is a substantial component of the human skin microbiota, but also one of the major causes of nosocomial infection in the context of implanted medical devices. We here aimed to advance the understanding of S. epidermidis genotypes and phenotypes conducive to infection establishment. Furthermore, we investigate the adaptation of individual clonal lines to the infection lifestyle based on the detailed analysis of individual S. epidermidis populations of 23 patients suffering from prosthetic joint infection. Analysis of invasive and colonizing S. epidermidis provided evidence that invasive S. epidermidis are characterized by infection-supporting phenotypes (e.g. increased biofilm formation, growth in nutrient poor media and antibiotic resistance), as well as specific genetic traits. The discriminating gene loci were almost exclusively assigned to the mobilome. Here, in addition to IS256 and SCCmec, chromosomally integrated phages was identified for the first time. These phenotypic and genotypic features were more likely present in isolates belonging to sequence type (ST) 2. By comparing seven patient-matched nasal and invasive S. epidermidis isolates belonging to identical genetic lineages, infection-associated phenotypic and genotypic changes were documented. Besides increased biofilm production, the invasive isolates were characterized by better growth in nutrient-poor media and reduced hemolysis. By examining several colonies grown in parallel from each infection, evidence for genetic within-host population heterogeneity was obtained. Importantly, subpopulations carrying IS insertions in agrC, mutations in the acetate kinase (AckA) and deletions in the SCCmec element emerged in several infections. In summary, these results shed light on the multifactorial processes of infection adaptation and demonstrate how S. epidermidis is able to flexibly repurpose and edit factors important for colonization to facilitate survival in hostile infection environments.

2.
Front Vet Sci ; 7: 603, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33134336

RESUMEN

Porcine reproductive and respiratory syndrome virus (PRRSV) has had a devastating impact on the pig industry in China, and monitoring its genetic diversity is important for epidemiological surveillance and understanding its evolution. Here, we determine the complete genome sequences of two PRRSV strains, GXYL1403 and GXNN1839. Comparative, phylogenetic, and recombination detection program analyses show that the two isolates are recombinant strains with large-fragment amino acid deletions in nsp2. GXYL1403 possesses a unique deletion region of 124 amino acids in nsp2, and GXNN1839 contains a deletion of 131 amino acids in nsp2 as compared with VR2332. Further analysis of the full-length sequence suggests that GXYL1403 is a natural recombinant between sublineages 8.1 (CH-1a like) and 8.3 (JXA1-like). The recombination site of GXYL1403 is located in nsp9-nsp12 (8961nt-11181nt). GXNN1839 is a natural recombinant between the lineage 5 (VR-2332-like) and lineage 1 (NADC30-like) strains. The recombination events occurred in nsp9 (7872nt-8162nt) and in ORF2 (12587nt-13282nt) in the genome of GXNN1839. These results provide new evidence that PRRSV strains circulating in the environment have undergone recombination among the different lineages or sublineages of field strains, and these add to our understanding of RNA combination events that occur in PRRSV.

3.
Front Neurol ; 11: 532110, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33192967

RESUMEN

Objective: Neuroimaging studies on neuropathic pain have discovered abnormalities in brain structure and function. However, the brain pattern changes from herpes zoster (HZ) to postherpetic neuralgia (PHN) remain unclear. The present study aimed to compare the brain activity between HZ and PHN patients and explore the potential neural mechanisms underlying cognitive impairment in neuropathic pain patients. Methods: Resting-state functional magnetic resonance imaging (MRI) was carried out among 28 right-handed HZ patients, 24 right-handed PHN patients, and 20 healthy controls (HC), using a 3T MRI system. The amplitude of low-frequency fluctuation (ALFF) was analyzed to detect the brain activity of the patients. Correlations between ALFF and clinical pain scales were assessed in two groups of patients. Differences in brain activity between groups were examined and used in a support vector machine (SVM) algorithm for the subjects' classification. Results: Spontaneous brain activity was reduced in both patient groups. Compared with HC, patients from both groups had decreased ALFF in the precuneus, posterior cingulate cortex, and middle temporal gyrus. Meanwhile, the neural activities of angular gyrus and middle frontal gyrus were lowered in HZ and PHN patients, respectively. Reduced ALFF in these regions was associated with clinical pain scales in PHN patients only. Using SVM algorithm, the decreased brain activity in these regions allowed for the classification of neuropathic pain patients (HZ and PHN) and HC. Moreover, HZ and PHN patients are also roughly classified by the same model. Conclusion: Our study indicated that mean ALFF values in these pain-related regions can be used as a functional MRI-based biomarker for the classification of subjects with different pain conditions. Altered brain activity might contribute to PHN-induced pain.

4.
Immun Inflamm Dis ; 8(4): 753-762, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33124193

RESUMEN

BACKGROUND: Severe acute respiratory syndrome coronavirus clade 2 (SARS-CoV-2) is a single-stranded RNA virus responsible for the global pandemic of the coronavirus disease-2019 (COVID-19). To date, there are still no effective approaches for the prevention and treatment of COVID-19. OBJECTIVE: The present study aims to explore the possible mechanisms of SARS-CoV-2 infection in human lung cells. METHODS: Data interpretation was conducted by recruiting bioinformatics analysis, including Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways analysis using downloaded data from the NCBI Gene Expression Omnibus database. RESULTS: The present study demonstrated that SARS-CoV-2 infection induces the upregulation of 14 interferon-stimulated genes, indicative of immune, and interferon responses to the virus. Notably, genes for pyrimidine metabolism and steroid hormone biosynthesis are selectively enriched in human lung cells after SARS-CoV-2 infection, suggesting that altered pyrimidine metabolism and steroid biosynthesis are remarkable, and perhaps druggable features after SARS-CoV-2 infection. Besides, there is a strong positive correlation between viral ORF1ab, ORF6, and angiotensin-converting enzyme 2 (ACE2) expression in human lung cells, implying that ACE2 facilitates SARS-CoV-2 infection and replication in host cells probably through the induction of ORF1ab and ORF6.


Asunto(s)
Betacoronavirus/patogenicidad , Infecciones por Coronavirus/etiología , Interferones/metabolismo , Pulmón/patología , Peptidil-Dipeptidasa A/metabolismo , Neumonía Viral/etiología , Betacoronavirus/metabolismo , Biología Computacional , Infecciones por Coronavirus/patología , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Células Epiteliales/virología , Perfilación de la Expresión Génica , Humanos , Pulmón/citología , Pulmón/inmunología , Pulmón/virología , Pandemias , Neumonía Viral/patología , Poliproteínas , Pirimidinas/metabolismo , Mucosa Respiratoria/citología , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/virología , Transducción de Señal/inmunología , Esteroides/biosíntesis , Regulación hacia Arriba/inmunología , Proteínas Virales/metabolismo
5.
Artículo en Inglés | MEDLINE | ID: mdl-33007476

RESUMEN

OBJECTIVES: Investigation whether in depth characterization of virus variant patterns can be used for epidemiological analysis of the first SARS-CoV-2 infection clusters in Hamburg, Germany. METHODS: Metagenomic RNA- and amplicon-sequencing and subsequent variant calling in 25 respiratory samples from SARS-CoV-2 infected patients involved in the earliest infection clusters in Hamburg. RESULTS: Amplikon sequencing and cluster analyses of these SARS-CoV-2 sequences allowed the identification of the first infection cluster and five non-related infection clusters occurring at the beginning of the viral entry of SARS-CoV-2 in the Hamburg metropolitan region. Viral genomics together with epidemiological analyses revealed that the index patient acquired the infection in Northern Italy and transmitted it to two out of 134 contacts. Single nucleotide polymorphisms clearly distinguished the virus variants of the index and other clusters and allowed to track in which sequences worldwide these mutations were first described. Minor variant analyses identified the transmission of intra-host variants in the index cluster and household clusters. CONCLUSIONS: SARS-CoV-2 variant tracing allows the identification of infection clusters and the follow up of infection chains occurring in the population. Furthermore, the follow up of minor viral variants in infection cluster can provide further resolution on transmission events indistinguishable on consensus sequence level.

6.
J Clin Neurophysiol ; 2020 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-32675727

RESUMEN

BACKGROUND: Medication is the main approach for early treatment of herpes zoster, but it could be ineffective in some patients. It is highly desired to predict the medication responses to control the degree of pain for herpes zoster patients. The present study is aimed to elucidate the relationship between medication outcome and neural activity using EEG and to establish a machine learning model for early prediction of the medication responses from EEG. METHODS: The authors acquired and analyzed eye-closed resting-state EEG data 1 to 2 days after medication from 70 herpes zoster patients with different drug treatment outcomes (measured 5-6 days after medication): 45 medication-sensitive pain patients and 25 medication-resistant pain patients. EEG power spectral entropy of each frequency band was compared at each channel between medication-sensitive pain and medication-resistant pain patients, and those features showing significant difference between two groups were used to predict medication outcome with different machine learning methods. RESULTS: Medication-sensitive pain patients showed significantly weaker beta-band power spectral entropy in the central-parietal regions than medication-resistant pain patients. Based on these EEG power spectral entropy features and a k-nearest neighbors classifier, the medication outcome can be predicted with 80% ± 11.7% accuracy, 82.5% ± 14.7% sensitivity, 77.7% ± 27.3% specificity, and an area under the receiver operating characteristic curve of 0.85. CONCLUSIONS: EEG beta-band power spectral entropy in the central-parietal region is predictive of the effectiveness of drug treatment on herpes zoster patients, and it could potentially be used for early pain management and therapeutic prognosis.

7.
J Am Med Dir Assoc ; 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32682600

RESUMEN

OBJECTIVE: Sex-specific impact of frailty on all-cause mortality in older age population remains controversial. This meta-analysis aimed to evaluate the association between frailty and all-cause mortality in older age women vs men from the general population. DESIGN: Meta-analysis. SETTING AND PARTICIPANTS: PubMed and Embase databases were searched until March 25, 2020 for studies reporting sex-specific association of frailty phenotype or index with all-cause mortality among the older general population (age ≥60 years) in the same study. MEASUREMENTS: All-cause mortality for the frail vs robust individuals. RESULTS: Eight studies enrolling a total of 87, 000 individuals were identified. Using the frailty phenotype, the pooled risk ratio of all-cause mortality was 2.41 [95% confidence interval (CI) 2.07-2.80] for frail women and 2.94 (95% CI 2.12-4.09) for frail men. Using the frailty index, the pooled risk ratio of all-cause mortality was 3.23 (95% CI 2.16-4.83) for frail women and 2.63 (95% CI 2.33-2.98) for frail men. The pooled female-to-male ratio of relative risks was 0.93 (95% CI 0.76-1.13) for the frailty phenotype and 1.22 (95% CI 0.79-1.88) for the frailty index. CONCLUSIONS AND IMPLICATIONS: Older men and women with frailty confer a higher risk of all-cause mortality in the general population from the same source. However, there is no significant sex difference in the association between phenotype or index and all-cause mortality.

8.
Microbiol Resour Announc ; 9(23)2020 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-32499358

RESUMEN

Here, we describe the complete genome sequence of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain isolated from an oropharyngeal swab sample from a female patient with COVID-19 who was infected in Hamburg, northern Germany.

9.
Arch Virol ; 165(8): 1803-1813, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32474688

RESUMEN

In recent years, the availability of reverse genetics systems for porcine reproductive and respiratory syndrome virus (PRRSV) has created new perspectives for the use of recombinant viruses as expression vectors. Most of these recombinant PRRSV vectors express foreign genes through either an independent transcription unit inserted in ORF1b and ORF2, or in ORF7 and the 3' UTR. The aim of this study was to find an alternative site for foreign gene insertion into the PRRSV genome. Here, we constructed an infectious cDNA clone for a cell-adapted PRRSV strain, GXNN1396-P96. This cDNA-clone-derived recombinant virus (rGXAM) was comparable in its growth kinetics in MARC-145 cells to the parental virus, GX1396-P96. Using the infectious cDNA-clone, we inserted an independent transcription unit in ORF4 and ORF5a to generate a novel PRRSV-based recombinant virus expressing the green fluorescent protein (GFP) gene. Biological characterization of the recombinant virus, rGX45BSTRS-GFP, showed that it maintained similar growth characteristics but produced fewer infectious virions than the parental PRRSV. These data demonstrate that the ORF4 and ORF5a site is able to tolerate the insertion of foreign genes.


Asunto(s)
Marcadores Genéticos/genética , Sistemas de Lectura Abierta/genética , Síndrome Respiratorio y de la Reproducción Porcina/virología , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Animales , Línea Celular , Proteínas Fluorescentes Verdes/genética , Porcinos , Replicación Viral/genética
10.
Artículo en Inglés | MEDLINE | ID: mdl-32275584

RESUMEN

We present an approach for jointly matching and segmenting object instances of the same category within a collection of images. In contrast to existing algorithms that tackle the tasks of semantic matching and object co-segmentation in isolation, our method exploits the complementary nature of the two tasks. The key insights of our method are two-fold. First, the estimated dense correspondence fields from semantic matching provide supervision for object co-segmentation by enforcing consistency between the predicted masks from a pair of images. Second, the predicted object masks from object co-segmentation, in turn, allow us to reduce the adverse effects due to background clutters for improving semantic matching. Our model is end-to-end trainable and does not require supervision from manually annotated correspondences and object masks. We validate the efficacy of our approach on five benchmark datasets: TSS, Internet, PF-PASCAL, PF-WILLOW, and SPair-71k, and show that our algorithm performs favorably against the state-of-the-art methods on both semantic matching and object co-segmentation tasks.

11.
Pain Physician ; 23(2): E219-E230, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32214307

RESUMEN

BACKGROUND: Some 7.7% of the Chinese population suffer from herpes zoster each year, with 29.8% proceeding on to develop postherpetic neuralgia (PHN). This amounts to over 32 million people per year. PHN is preceded by 2 phases of pain: acute herpetic neuralgia (AHN), and subacute herpetic neuralgia (SHN). Considering the large individual and economic burden, preventing the transition of AHN/SHN to PHN is crucial. However, to date this has been difficult. OBJECTIVES: To evaluate the efficacy of temporary spinal cord stimulation (tSCS) treatment and prevention of PHN. STUDY DESIGN: A retrospective, observational study. SETTING: Department of Pain Medicine. METHODS: From 2013 to 2017, 99 patients with AHN (n = 42), SHN (n = 34), and PHN (n = 23) underwent tSCS treatment (7-14 days) after failed pharmacologic and interventional therapies. Visual analog scale (VAS), Pittsburgh Sleep Quality Index (PSQI), and analgesic consumption were recorded at baseline, post-tSCS, and 1, 3, 6, and 12 months after tSCS treatment. RESULTS: Pooled results demonstrated statistically significant decreases in VAS scores and PSQI post-tSCS and at 1, 3, 6, and 12 months follow-up (P < 0.001). When compared with the PHN group, both AHN and SHN groups were clinically and statistically improved in VAS scores and PSQI (P < 0.001). Analgesic consumption decreased in all 3 groups after tSCS treatment, and downward linear gradient of medication in the AHN group was more significant than that in the SHN and PHN groups. At 12 months follow-up, 2.5% (1/40) patients in the AHN group, 16.0% (4/25) in the SHN group, and 62.5% (10/16) in the PHN group had ongoing pain >= 3/10 VAS score requiring analgesia. Expressed differently, at 12 months, 97.5% of the AHN group and 84% of the SHN group had pain of 2/10 VAS score or less versus only 37.5% of the PHN group. LIMITATIONS: This was a single-center, retrospective study, which made it difficult to collect complete data for all variables. The therapeutic effect of tSCS could not be studied independently. CONCLUSIONS: This retrospective analyses of 99 patients treated with tSCS (7-14 days) suggests that tSCS may be effective for treating and preventing PHN. Early treatment within 4 to 8 weeks was more likely to result in pain <= 2/10 VAS score, improvement in sleep, and no requirement for analgesia at 12 months. Early tSCS may be a promising prevention strategy against the development of chronic neuropathic pain following herpes zoster infection. Further research is justified. KEY WORDS: Herpes zoster, zoster-related pain, postherpetic neuralgia, temporary spinal cord stimulation.


Asunto(s)
Herpes Zóster/terapia , Neuralgia Posherpética/prevención & control , Manejo del Dolor/métodos , Estimulación de la Médula Espinal/métodos , Anciano , Femenino , Estudios de Seguimiento , Herpes Zóster/diagnóstico por imagen , Herpes Zóster/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Neuralgia Posherpética/diagnóstico por imagen , Neuralgia Posherpética/epidemiología , Dimensión del Dolor/métodos , Estudios Retrospectivos , Resultado del Tratamiento
12.
IEEE Trans Pattern Anal Mach Intell ; 42(6): 1424-1438, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30794167

RESUMEN

We address the problem of weakly supervised object localization where only image-level annotations are available for training object detectors. Numerous methods have been proposed to tackle this problem through mining object proposals. However, a substantial amount of noise in object proposals causes ambiguities for learning discriminative object models. Such approaches are sensitive to model initialization and often converge to undesirable local minimum solutions. In this paper, we propose to overcome these drawbacks by progressive representation adaptation with two main steps: 1) classification adaptation and 2) detection adaptation. In classification adaptation, we transfer a pre-trained network to a multi-label classification task for recognizing the presence of a certain object in an image. Through the classification adaptation step, the network learns discriminative representations that are specific to object categories of interest. In detection adaptation, we mine class-specific object proposals by exploiting two scoring strategies based on the adapted classification network. Class-specific proposal mining helps remove substantial noise from the background clutter and potential confusion from similar objects. We further refine these proposals using multiple instance learning and segmentation cues. Using these refined object bounding boxes, we fine-tune all the layer of the classification network and obtain a fully adapted detection network. We present detailed experimental validation on the PASCAL VOC and ILSVRC datasets. Experimental results demonstrate that our progressive representation adaptation algorithm performs favorably against the state-of-the-art methods.

13.
Mol Genet Genomic Med ; 8(2): e1097, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31876394

RESUMEN

BACKGROUND: Y-chromosomal genetic marker haplotypes of individuals can define the paternal kinship or genealogies to which they belong and further provide clues for forensic individual identifications. Studying the genetic structure of the Mongolian group will help to bring to light the Mongolian ethnic origin, and explicate the genetic affinities among the studied and compared populations. Some forensic scientists have studied the genetic background of the Mongolian group based on different molecular genetic markers. These studies were of very great reference significance for the Mongolian group genetic research, whereas the investigation of Y-STR haplotype data in the Xinjiang Mongolian group is still insufficient. METHODS: Genetic characteristics of 182 unrelated healthy male Mongolian individuals were revealed by 41 Y-chromosomal short tandem repeat and 3 insertion/deletion molecular genetic markers. Furthermore, analyses of molecular variance programs, multi-dimensional scaling plots, and phylogenetic tree reconstructions were operated to explore the genetic relationships of the Xinjiang Mongolian group with comparative 23 populations from China and 33 populations from worldwide nations. RESULTS: The genetic diversity values ranged from 0.0641 (rs771783753) to 0.9502 (DYF387S1). A total of 165 distinct haplotypes were identified, of which 150 (90.91%) were unique. The discrimination capacity, match probability, and haplotype diversity of 44 loci were 0.9066, 0.0067, and 0.9988, respectively. Additionally, the Mongolian group had the most intimate relationship with Gansu Dongxiang (RST  = 0.0165), followed by HulunBuir Mongolian (RST  = 0.0187), Inner Mongolia Daur (RST  = 0.0202) as well as other three minority ethnic groups from the Xinjiang region (RST  < 0.05) in all compared Chinese populations, and clustered together with the majority of Asian populations in a worldwide scale. CONCLUSIONS: Consequently, the 44 loci could be well applied in forensic applications of the Mongolian group. The haplotypes available in here made new contributions to the existing population genetic information and would be of great value in population studies.

14.
Front Neurosci ; 13: 534, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31191228

RESUMEN

Herpes zoster (HZ) can cause a blistering skin rash with severe neuropathic pain. Pharmacotherapy is the most common treatment for HZ patients. However, most patients are usually the elderly or those that are immunocompromised, and thus often suffer from side effects or easily get intractable post-herpetic neuralgia (PHN) if medication fails. It is challenging for clinicians to tailor treatment to patients, due to the lack of prognosis information on the neurological pathogenesis that underlies HZ. In the current study, we aimed at characterizing the brain structural pattern of HZ before treatment with medication that could help predict medication responses. High-resolution structural magnetic resonance imaging (MRI) scans of 14 right-handed HZ patients (aged 61.0 ± 7.0, 8 males) with poor response and 15 (aged 62.6 ± 8.3, 5 males) age- (p = 0.58), gender-matched (p = 0.20) patients responding well, were acquired and analyzed. Multivoxel pattern analysis (MVPA) with a searchlight algorithm and support vector machine (SVM), was applied to identify the spatial pattern of the gray matter (GM) volume, with high predicting accuracy. The predictive regions, with an accuracy higher than 79%, were located within the cerebellum, posterior insular cortex (pIC), middle and orbital frontal lobes (mFC and OFC), anterior and middle cingulum (ACC and MCC), precuneus (PCu) and cuneus. Among these regions, mFC, pIC and MCC displayed significant increases of GM volumes in patients with poor response, compared to those with a good response. The combination of sMRI and MVPA might be a useful tool to explore the neuroanatomical imaging biomarkers of HZ-related pain associated with medication responses.

15.
Int J Eat Disord ; 52(6): 712-720, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30883838

RESUMEN

OBJECTIVE: According to the ICD-10 and DSM-5, eating disorders (EDs) are classified using a categorical model that assumes the subtypes are qualitatively different from one another. However, it is still intensely debated that a dimensional model is more suitable. The aim of this study is to examine whether EDs have a categorical or dimensional latent structure using a sample of Chinese ED patients. METHOD: The sample included 322 patients, diagnosed with an ED from 2010 to 2017 in the Shanghai Mental Health Center, and comparison participants (N = 850), recruited from undergraduate students in one university in Shanghai. Participants were evaluated with the Eating Disorder Inventory-2 (EDI-2) questionnaire and another questionnaire developed by the researchers. Three taxometric procedures (MAXimum EIGenvalue [MAXEIG], latent-mode factor analysis [L-Mode], and Mean Above Minus Below A Cut [MAMBAC]) were applied, respectively, to analyze the patients' clinical symptoms data. RESULTS: Patients were divided into three groups according to their clinical diagnosis. The plots of the three taxometric analysis procedures supported the categorical construct in anorexia nervosa, binge-eating/purging group, and bulimia nervosa group. The Comparison Curve Fit Indices of the MAXEIG, L-Mode, and MAMBAC procedures were 0.694, 0.709, 0.704 in the AN-BP group and 0.727, 0.67, 0.62 in the BN group, respectively, which also support the categorical construct. DISCUSSION: The results support two distinct classes of ED subtypes among Chinese sample. Further work on applying hybrid model in analysis has been discussed.


Asunto(s)
Trastorno por Atracón/clasificación , Adolescente , Adulto , Grupo de Ascendencia Continental Asiática , Trastorno por Atracón/psicología , Niño , China , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Adulto Joven
16.
IEEE Trans Pattern Anal Mach Intell ; 41(8): 1909-1923, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30605094

RESUMEN

Joint image filters leverage the guidance image as a prior and transfer the structural details from the guidance image to the target image for suppressing noise or enhancing spatial resolution. Existing methods either rely on various explicit filter constructions or hand-designed objective functions, thereby making it difficult to understand, improve, and accelerate these filters in a coherent framework. In this paper, we propose a learning-based approach for constructing joint filters based on Convolutional Neural Networks. In contrast to existing methods that consider only the guidance image, the proposed algorithm can selectively transfer salient structures that are consistent with both guidance and target images. We show that the model trained on a certain type of data, e.g., RGB and depth images, generalizes well to other modalities, e.g., flash/non-Flash and RGB/NIR images. We validate the effectiveness of the proposed joint filter through extensive experimental evaluations with state-of-the-art methods.

17.
FASEB J ; 33(2): 2359-2371, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30285578

RESUMEN

Experimental nephrotoxic serum nephritis (NTN) is a model for T-cell-mediated human rapid progressive glomerulonephritis. T-cell receptor stimulation involves intracellular signaling events that ultimately lead to the activation of transcription factors, such as NF-κB. We explored the involvement of the NF-κB components IKK-2 and NEMO in NTN, by using cell-specific knockouts of IKK-2 and NEMO in CD4+ T lymphocytes. Our results demonstrate that although the course of disease was not grossly altered in CD4xIKK2Δ and CD4xNEMOΔ animals, renal regulatory T cells were significantly reduced and T helper (Th)1 and Th17 cells significantly increased in both knockout mouse groups. The expression of the renal cytokines and chemokines IL-1ß, CCL-2, and CCL-20 was also significantly altered in both knockout mice. Lymphocyte transcriptome analysis confirmed the increased expression of Th17-related cytokines in spleen CD4+ T cells. Moreover, our array data demonstrate an interrupted canonical NF-κB pathway and an increased expression of noncanonical NF-κB pathway-related genes in nephritic CD4xNEMOΔ mice, highlighting different downstream effects of deletion of IKK-2 or NEMO in T lymphocytes. We propose that better understanding of the role of IKK-2 and NEMO in nephritis is essential for the clinical application of kinase inhibitors in patients with glomerulonephritis.-Guo, L., Huang, J., Chen, M., Piotrowski, E., Song, N., Zahner, G., Paust, H.-J., Alawi, M., Geffers, R., Thaiss, F. T-lymphocyte-specific knockout of IKK-2 or NEMO induces Th17 cells in an experimental nephrotoxic nephritis mouse model.


Asunto(s)
Modelos Animales de Enfermedad , Quinasa I-kappa B/fisiología , Péptidos y Proteínas de Señalización Intracelular/fisiología , Nefritis/patología , Linfocitos T/metabolismo , Células Th17/inmunología , Animales , Células Cultivadas , Citocinas/metabolismo , Masculino , Ratones , Ratones Noqueados , FN-kappa B/genética , FN-kappa B/metabolismo , Nefritis/inducido químicamente , Nefritis/inmunología , Fosforilación , Transducción de Señal , Células Th17/metabolismo , Células Th17/patología
18.
J Autoimmun ; 97: 29-39, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30420263

RESUMEN

Dysbiosis¸ i.e. changes in microbial composition at a mucosal interface, is implicated in the pathogenesis of many chronic inflammatory and autoimmune diseases. To assess the composition of the microbial upper respiratory tract (URT) community in patients with granulomatosis with polyangiitis (GPA), we used culture-independent high-throughput methods. In this prospective clinical study, nasal swabs were collected from patients with GPA, patients with rheumatoid arthritis (RA, disease control), and healthy controls. Nasal bacterial taxa were assessed using V3-V4 region 16S rRNA amplicon sequencing. Staphylococcus aureus, Haemophilus influenza, and entero- and rhinoviruses were detected using qPCR. Unbiased metagenomic RNA sequencing (UMERS) was performed in a subset of samples to determine the relative abundance of bacterial, fungal, and viral species. A trend toward reduced microbiome diversity was detected in GPA samples compared with healthy controls. The abundance of bacterial taxa and microbial richness were significantly decreased in GPA samples compared with RA samples. The relative abundance of bacterial families shifted, with increased Planococcaceae and decreased Moraxellaceae, Tissierellaceae, Staphylococcaceae, and Propionibacteriaceae in GPA and RA. Further, decreased abundance of Corynebacteriaceae, and Aerococcaceae was observed in GPA samples. Significantly more colonization of S. aureus was seen in the nasal microbiome of GPA compared with RA and healthy control samples. H. influenzae colonization was also observed in GPA samples. UMERS detected the presence of rhinoviral sequences in some GPA samples. Thus, our study uncovered changes in the URT microbial composition in patients with GPA and RA, suggesting that both immunosuppression and disease background affect the URT microbiome. Complex alterations of host-microbiome interactions in the URT could influence chronic endonasal inflammation in GPA.


Asunto(s)
Disbiosis , Granulomatosis con Poliangitis/etiología , Microbiota , Mucosa Respiratoria/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Artritis Reumatoide/inmunología , Biodiversidad , Estudios de Casos y Controles , Biología Computacional/métodos , Susceptibilidad a Enfermedades , Femenino , Humanos , Masculino , Metagenómica/métodos , Persona de Mediana Edad , ARN Ribosómico 16S , Adulto Joven
19.
IEEE Trans Pattern Anal Mach Intell ; 41(11): 2709-2723, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30106709

RESUMEN

Visual tracking is challenging as target objects often undergo significant appearance changes caused by deformation, abrupt motion, background clutter and occlusion. In this paper, we propose to exploit the rich hierarchical features of deep convolutional neural networks to improve the accuracy and robustness of visual tracking. Deep neural networks trained on object recognition datasets consist of multiple convolutional layers. These layers encode target appearance with different levels of abstraction. For example, the outputs of the last convolutional layers encode the semantic information of targets and such representations are invariant to significant appearance variations. However, their spatial resolutions are too coarse to precisely localize the target. In contrast, features from earlier convolutional layers provide more precise localization but are less invariant to appearance changes. We interpret the hierarchical features of convolutional layers as a nonlinear counterpart of an image pyramid representation and explicitly exploit these multiple levels of abstraction to represent target objects. Specifically, we learn adaptive correlation filters on the outputs from each convolutional layer to encode the target appearance. We infer the maximum response of each layer to locate targets in a coarse-to-fine manner. To further handle the issues with scale estimation and re-detecting target objects from tracking failures caused by heavy occlusion or out-of-the-view movement, we conservatively learn another correlation filter, that maintains a long-term memory of target appearance, as a discriminative classifier. We apply the classifier to two types of object proposals: (1) proposals with a small step size and tightly around the estimated location for scale estimation; and (2) proposals with large step size and across the whole image for target re-detection. Extensive experimental results on large-scale benchmark datasets show that the proposed algorithm performs favorably against the state-of-the-art tracking methods.

20.
IEEE Trans Pattern Anal Mach Intell ; 41(11): 2599-2613, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30106708

RESUMEN

Convolutional neural networks have recently demonstrated high-quality reconstruction for single image super-resolution. However, existing methods often require a large number of network parameters and entail heavy computational loads at runtime for generating high-accuracy super-resolution results. In this paper, we propose the deep Laplacian Pyramid Super-Resolution Network for fast and accurate image super-resolution. The proposed network progressively reconstructs the sub-band residuals of high-resolution images at multiple pyramid levels. In contrast to existing methods that involve the bicubic interpolation for pre-processing (which results in large feature maps), the proposed method directly extracts features from the low-resolution input space and thereby entails low computational loads. We train the proposed network with deep supervision using the robust Charbonnier loss functions and achieve high-quality image reconstruction. Furthermore, we utilize the recursive layers to share parameters across as well as within pyramid levels, and thus drastically reduce the number of parameters. Extensive quantitative and qualitative evaluations on benchmark datasets show that the proposed algorithm performs favorably against the state-of-the-art methods in terms of run-time and image quality.

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