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Two new indole alkaloids, colletotryptins G (1) and H (2), along with four known alkaloids (3 – 6), were isolated from an endophytic fungus Colletotrichum sp. HD-1 (Melanconiaceae) derived from the mangrove plant Acrostichum aureum (Pteridaceae). The structures of new compounds were elucidated by comprehensive analysis of their UV, HRESIMS, and NMR data. All the isolates were evaluated for their α -glucosidase and acetylcholinesterase inhibitory, antibacterial, and antifungal activities. Only compound 2 showed stronger inhibitory activity against α -glucosidase with IC 50 value of 133.4 μM than that of the positive control acarbose (319.8 μM). [Display omitted] • Indole alkaloids are the main metabolites of endophytic fungus Colletotrichum sp. • Two new indole alkaloids (1 and 2) were isolated and identified from this fungus. • Compound 2 showed better α -glucosidase inhibitory activity than acarbose. [ABSTRACT FROM AUTHOR]

This study investigated the outcome after neonatal arch repair, and the usefulness of computed tomography (CT) in predicting the development of left ventricular outflow tract (LVOT) obstruction (LVOTO). A total of 150 neonates who underwent arch repair between 2008 and 2019 were included. The diameters of the aortic valve annulus (AVA) and LVOT in millimeters were measured with transthoracic echocardiography (TTE) or CT and indexed by subtracting body weight in kilograms. The outcomes of interest were the development of LVOTO (peak flow velocity > 3 m/s on TTE) and reintervention or reoperation for LVOTO. The median follow-up duration was 3.6 years. The rates of overall survival, freedom from reintervention for LVOTO, and freedom from the LVOTO development at 7 years were 93.7%, 88.2%, and 81.0%, respectively. In univariable Cox regression analysis, weight-indexed CT-measured LVOT diameter (concordance index [C-index] = 0.73, P = 0.002) and weight-indexed TTE-measured AVA diameter (C-index = 0.69, P = 0.001) were significant predictors of LVOTO. The maximal chi-square test identified the following cutoff values for predicting LVOTO: 1.4 for weight-indexed CT-measured LVOT diameter and 1.6 for weight-indexed TTE-measured AVA diameter. The high-risk group (both measures lower than the cutoff values) had a significantly lower rate of freedom from LVOTO development than the low-risk group (both measures higher than the cutoff values) (P < 0.001). The weight-indexed CT-measured LVOT diameter could be used to predict LVOTO development after neonatal arch repair, as an independent measure or complementary to traditional measures. [Display omitted] [ABSTRACT FROM AUTHOR]

Considerable attention has been paid to interindividual differences in the cardiorespiratory fitness (CRF) response to exercise. However, the complex multifactorial nature of CRF response variability poses a significant challenge to our understanding of this issue. We aimed to explore whether unsupervised clustering can take advantage of large amounts of clinical data and identify latent subgroups with different CRF exercise responses within a healthy population. 252 healthy participants (99 men, 153 women; 36.8 ± 13.4 yr) completed moderate endurance training on 3 days/week for 4 months, with exercise intensity prescribed based on anaerobic threshold (AT). Detailed clinical measures, including resting vital signs, ECG, cardiorespiratory parameters, echocardiography, heart rate variability, spirometry and laboratory data, were obtained before and after the exercise intervention. Baseline phenotypic variables that were significantly correlated with CRF exercise response were identified and subjected to selection steps, leaving 10 minimally redundant variables, including age, BMI, maximal oxygen uptake (VO 2max), maximal heart rate, VO 2 at AT as a percentage of VO 2max , minute ventilation at AT, interventricular septal thickness of end-systole, E velocity, root mean square of heart rate variability, and hematocrit. Agglomerative hierarchical clustering was performed on these variables to detect latent subgroups that may be associated with different CRF exercise responses. Unsupervised clustering revealed two mutually exclusive groups with distinct baseline phenotypes and CRF exercise responses. The two groups differed markedly in baseline characteristics, initial fitness, echocardiographic measurements, laboratory values, and heart rate variability parameters. A significant improvement in CRF following the 16-week endurance training, expressed by the absolute change in VO 2max , was observed only in one of the two groups (3.42 ± 0.4 vs 0.58 ± 0.65 ml⋅kg−1⋅min−1, P = 0.002). Assuming a minimal clinically important difference of 3.5 ml⋅kg−1⋅min−1 in VO 2max , the proportion of population response was 56.1% and 13.9% for group 1 and group 2, respectively (P< 0.001). Although group 1 exhibited no significant improvement in CRF at group level, a significant decrease in diastolic blood pressure (70.4 ± 7.8 vs 68.7 ± 7.2 mm Hg, P = 0.027) was observed. Unsupervised learning based on dense phenotypic characteristics identified meaningful subgroups within a healthy population with different CRF responses following standardized aerobic training. Our model could serve as a useful tool for clinicians to develop personalized exercise prescriptions and optimize training effects. [ABSTRACT FROM AUTHOR]

Spiders spin a great diversity of silk types for daily survival and reproduction. Of the six orb-weaver silk types, the dragline silk forming orb web frame attracts the most attention because of its extremely high tensile strength and toughness. So far, four types of major ampullate silk proteins (MaSp1-4) that make up dragline silk have been identified. These MaSp types have diversified amino acid motifs that underlie the impressive mechanical property of dragline silk by forming particular structures. Existing knowledge of MaSp4 proteins is fragmented, making it difficult to illuminate the structure and function of MaSp4. Here, we report the full-length MaSp4 gene with 11,334 bp from the orb-weaving spider Araneus ventricosus. Removing the only intron, the spliced complete transcript of MaSp4 gene is 6897 bp and encodes 2298 amino acids. Analysis of the primary structure of A. ventricosus MaSp4 protein reveals the repetitive region lacks poly-A and GGX motifs but has the unique GPGPQ motifs. Quantitative real-time PCR analyses show high levels of MaSp4 mRNA were detected in major ampullate gland. Structural characterization using CD- and FTIR sepctroscopy reveals a mainly α-helical solution conformation and a very high β-turn content within fibers. Collectively, our new findings provide complete template for recombinant silk protein with specific properties and support that the GPGPQ motif found in MaSp4 could increase flexibility in dragline silk by packing in more β-turns, expanding the repertoire of sequences known to form β-turn that is available for artificial chimeric silk fibers. Dragline silk forming orb web frame attracts the most attention because of its extremely high tensile strength and toughness. So far, four types of major ampullate silk proteins (MaSp1-4) that make up dragline silk have been identified. Existing knowledge of MaSp4 proteins is fragmented, making it difficult to illuminate the structure and function of MaSp4. Here, we report the full-length MaSp4 gene from the orb-weaving spider Araneus ventricosus. We further identify the sequence, structure, and mechanical property of MaSp4 protein, providing a new insight into the structure-funtion relationships associated with MaSp4. Collectively, our new findings provide complete template for recombinant silk protein with specific properties and support that the GPGPQ motif found in MaSp4 could increase flexibility in dragline silk by packing in more β-turns, expanding the repertoire of sequences known to form β-turn that is available for artificial chimeric silk fibers. [Display omitted] [ABSTRACT FROM AUTHOR]

Despite existing debates on the maritime cluster's institutional composition, geographical boundary, or evolutionary patterns, few studies have empirically scrutinized the relatedness of industrial sectors inside a maritime cluster. This study aims to develop an industry-relatedness model to quantitatively measure the paired industry relatedness among three maritime sectors: port-related, shipping-related, and maritime business services. Maritime sectors can be labour-intensive or capital-intensive, and thereby we constructed a compound ratio of capital per capita to address the heterogeneity issue in evaluating the industry relatedness. Instead of focusing on a specific maritime cluster, we applied the model to three representative maritime clusters, namely Western Europe, Guangdong-Hong Kong-Macao Greater Bay Area (GBA), and the Yangtze River Delta (YRD), to enhance the generalizability of our findings and implications. Findings suggest that the maritime cluster in Western Europe is characterized by more inter-sector connections. In Western Europe, Ship owning and operating , and Ship management and agency are found to operate with the highest relatedness; GBA has a polarized maritime industry structure with Hong Kong specializing in Ship finance and Shipbroking ; cities in YRD operate with a speciality in Shipbuilding and repairing. This study found that differences in industry relatedness are mainly attributable to the focal region's evolutionary history and governance structure. We also provided a valuable reference for policymakers to plan and improve local and regional maritime cluster development. • Modify the co-occurrence model by considering the heterogeneity of different maritime sectors. • Quantify the industry relatedness between different maritime sectors. • Compare three typical maritime clusters in terms of maritime industry-relatedness. [ABSTRACT FROM AUTHOR]