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In this study we used functional magnetic resonance imaging to investigate age-related changes in large-scale brain functional networks during memory encoding and recognition in 12 younger and 16 older adults. For each participant, functional brain networks were constructed by computing temporal correlation matrices of 90 brain regions and analyzed using graph theoretical approaches. We found the age-related changes mainly in the long-range connections with widespread reductions associated with aging in the fronto-temporal and temporo-parietal regions, and a few age-related increases in the posterior parietal regions. Graph theoretical analysis revealed that the older adults had longer path lengths linking different regions in the functional brain networks as compared to the younger adults. Further analysis indicated that the increases in shortest path length in the networks were combined with the loss of long-range connections. Finally, we showed that for older adults, frontal areas played reduced roles in the network (reduced regional centrality), whereas several default-mode regions played increased roles relative to younger subjects (increased regional centrality). Together, our results suggest that normal aging is associated with disruption of large-scale brain systems during the performance of memory tasks, which provides novel insights into the understanding of age-related decline in multiple cognitive functions.

It remains unclear whether airway smooth muscle (ASM) mechanics is altered in asthma. While efforts have originally focussed on contractile force, some evidence points to an increased velocity of shortening. A greater rate of airway renarrowing after a deep inspiration has been reported in asthmatics compared to controls, which could result from a shortening velocity increase. In addition, we have recently shown in rats that increased shortening velocity correlates with increased muscle shortening, without increasing muscle force. Nonetheless, establishing whether or not asthmatic ASM shortens faster than that of normal subjects remains problematic. Endobronchial biopsies provide excellent tissue samples because the patients are well characterized, but the size of the samples allows only cell level experiments. Whole human lungs from transplant programs suffer primarily from poor patient characterization, leading to high variability. ASM from several animal models of asthma has shown increased shortening velocity, but it is unclear whether this is representative of human asthma. Several candidates have been suggested as responsible for increased shortening velocity in asthma, such as alterations in contractile protein expression or changes in the contractile apparatus structure. There is no doubt that more remains to be learned about the role of shortening velocity in asthma.

The inclusion of able-bodied athletes within disability sport, a phenomenon known as reverse integration, has sparked significant debate within adapted physical activity. Although researchers and practitioners have taken up positions for or against reverse integration, there is a lack of supporting research on the experiences of athletes who already play in such settings. In this study, we explore how competitive female athletes who have a disability experience reverse integration in Canadian wheelchair basketball. Athletic identity was used as the initial conceptual framework to guide semistructured interviews with nine participants. The results suggest that participation in this context contributed to positive athletic identities. Interviews also pointed to the unexpected theme of “what’s the difference?” that this sporting context provided a space for the questioning and creative negotiation of the categories of disability and able-bodiedness. Methodologically, this paper also explores the possibilities and challenges of inter- worldview and insider-outsider research collaboration.

Under the trend of antibiotic resistance of H. pylori leading to the decrease of eradication rate, the development of a vaccine is the best choice to fight against H. pylori. In this study, we attempted to reduce the amounts of required antigens by using three different parenteral routes of immunization and an adjuvant cGAMP (cyclic guanosine monophosphate-adenosine monophosphate) to enhance the immunogenicity of the vaccine candidate. The immune protection and post-challenge immune responses were assessed and compared in mice immunized with recombinant Helicobacter pylori urease A, urease B, and neutrophil-activating protein adjuvanted with cGAMP. The gastric mucosal colonization by H. pylori was significantly reduced in mice immunized by intranasal and, to a less degree, subcutaneous route, but not by intramuscular route. All immunized mice, regardless of the route of immunization, displayed significant, but comparable, increases in antigen-specific serum IgG and mucosal IgA responses 5 weeks post-challenge. The magnitude of the vaccine-induced protection appeared to be associated with the level of antigen-specific Th1 and particularly Th17 responses, as IL-17 responses were only detected in intranasally immunized mice. Taken together, we explored and confirmed the possibility of using a novel adjuvant (cGAMP) to induce significant protective immunity with 10% of oral vaccine antigen dosage through parenteral immunization, especially intranasal immunization. This may provide an alternative approach to oral immunization for the development of effective H. pylori vaccines.

ABSTRACT Objective: Stroke guideline compliance of rural Canadian prehospital emergency medical services (EMS) care in acute stroke is unknown. In this quality assurance study, we sought to compare rural and urban care by prehospital EMS evaluation/management indicators from patients assessed at an urban Canadian stroke center.Materials and Methods: One hundred adult patients were randomly selected from the stroke registry. Patients were transported through Rural EMS bypass protocols or urban EMS protocols (both bypass and direct) to our stroke center between January and December 2013. Patients were excluded if they were first evaluated at any other health center. Prehospital care was assessed using ten indicators for EMS evaluation/management, as recommended by acute stroke guidelines. Results: Compliance with acute stroke EMS evaluation/management indicators were statistically similar for both groups, except administrating a prehospital diagnostic tool (rural 31.8 vs. urban 70.3%; P = 0.002). Unlike urban EMS, rural EMS did not routinely document scene time. Conclusion: Rural EMS responders' compliance to prehospital stroke evaluation/management was similar to urban EMS responders. Growth areas for both groups may be with prehospital stroke diagnostic tool utilization, whereas rural EMS responders may also improve with scene time documentation.

The infant brain undergoes a remarkable period of neural development that is crucial for the development of cognitive and behavioral capacities (Hasegawa et al., 2018). Longitudinal magnetic resonance imaging (MRI) is able to characterize the developmental trajectories and is critical in neuroimaging studies of early brain development. However, missing data at different time points is an unavoidable occurrence in longitudinal studies owing to participant attrition and scan failure. Compared to dropping incomplete data, data imputation is considered a better solution to address such missing data in order to preserve all available samples. In this paper, we adapt generative adversarial networks (GAN) to a new application: longitudinal image prediction of structural MRI in the first year of life. In contrast to existing medical image-to-image translation applications of GANs, where inputs and outputs share a very close anatomical structure, our task is more challenging as brain size, shape and tissue contrast vary significantly between the input data and the predicted data. Several improvements over existing GAN approaches are proposed to address these challenges in our task. To enhance the realism, crispness, and accuracy of the predicted images, we incorporate both a traditional voxel-wise reconstruction loss as well as a perceptual loss term into the adversarial learning scheme. As the differing contrast changes in T1w and T2w MR images in the first year of life, we incorporate multi-contrast images leading to our proposed 3D multi-contrast perceptual adversarial network (MPGAN). Extensive evaluations are performed to assess the qualityand fidelity of the predicted images, including qualitative and quantitative assessments of the image appearance, as well as quantitative assessment on two segmentation tasks. Our experimental results show that our MPGAN is an effective solution for longitudinal MR image data imputation in the infant brain. We further apply our predicted/imputed images to two practical tasks, a regression task and a classification task, in order to highlight the enhanced task-related performance following image imputation. The results show that the model performance in both tasks is improved by including the additional imputed data, demonstrating the usability of the predicted images generated from our approach.

Zizyphus mauritiana Lam. is an important tropical fruit tree and has significant economic value. It is widely planted in Hainan, Guangdong, Guangxi and Fujian provinces in China (Yang et al. 2017). In March 2019, leaf spot was observed on leaves of Z. mauritiana at Bagui fields in Nanning, Guangxi, China, with incidence exceeding 50%. Symptomatic leaves developed a yellow to tan-brown sunken lesion and finally abscised. To isolate the pathogen causing the symptoms, small pieces (5 × 5 mm) of infected leaves were surface sterilized by exposure to 75% ethanol for 10 sec, 1% sodium hypochlorite for 1 min and rinsed three times in sterile water. Fifty pieces were isolated, surface sterilized, and pieces were plated onto potato dextrose agar (PDA) and grown at 28°C for 7 days. The isolation rate of Colletotrichum species was 100%. Three representative isolates (DQZ3-1, DQZ3-2 and DQZ3-3) were selected for further study. Mycelia were greyish-white for all three isolates, with isolate DQZ3-1 also appearing dark green in the center of the colony. Conidia were elliptical, aseptate and hyaline, with sizes of 13.4 ± 0.12 µm × 5.7 ± 0.1 µm, 14.8 ± 0.1 µm × 5.8 ± 0.1 µm and 15.1 ± 0.1 µm × 5.5 ± 0.1 µm for DQZ3-1, DQZ3-2 and DQZ3-3, respectively. Genomic DNA was extracted using the DNAsecure Plant Kit [Tiangen Biotech (Beijing) Co., Ltd] and the internal transcribed spacer (ITS), partial actin (ACT), calmodulin (CAL), chitin synthase (CHS-1), beta-tubulin (TUB2), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were sequenced (Weir et al. 2012). Phylogenetic analysis of the three isolates was performed with MEGA-X (Version 10.0) based on sequences of multiple loci (ITS, ACT, CAL, CHS-1, TUB2 and GAPDH) using Maximum Likelihood analysis. Isolate DQZ3-1 was identified as C. fructicola, and the other two isolates, DQZ3-2 and DQZ3-3, were identified as C. siamense (accessions MT039396 to MT039410, for ACT, CAL, CHS-1, GAPDH and TUB2 of DQZ3-1, DQZ3-2 and DQZ3-3; MT041651 to MT041653 for ITS of DQZ3-1, DQZ3-2 and DQZ3-3). Pathogenicity tests were conducted on 1-year-old plants. Young, healthy leaves were artificially wounded by gently scratching with a sterile needle and 10 µl droplets of conidial suspension (106 spores/ml) applied per wound site for each isolate. Some wounded leaves were inoculated with 10 µl droplets of water as controls. Each isolate was inoculated onto three plants, with 15 leaves at least for each plant, same as controls. All inoculated plants were sprayed with water and covered with plastic bags to maintain high humidity. Symptomatic lesions were observed on the inoculated leaves after 7 days at 28°C, whereas no symptoms were observed on the control leaves. To fulfill Koch's postulates, fungi were re-isolated from 50 symptomatic leaf pieces and fungi re-isolated from each leaf piece were morphologically identical to the inoculated isolates, for a 100% isolation frequency. To our knowledge, this is the first report of leaf spot caused by C. fructicola and C. siamense on Z. mauritiana worldwide. This research may accelerate the development of future epidemiological studies and management strategies for anthracnose caused by C. fructicola and C. siamense on Z. mauritiana.