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Context Premenopausal women are at a lower risk of type 2 diabetes (T2D) compared to men, but the underlying mechanism(s) remain elusive. The secretion of the incretin hormones, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), from the small intestine is a major determinant of glucose homeostasis and may be influenced by sex. Objectives This study compared blood glucose and plasma insulin and incretin responses to intraduodenal glucose infusions in healthy young males and females. Design In Study 1, 9 women and 20 men received an intraduodenal glucose infusion at 2 kcal/min for 60 minutes. In Study 2, 10 women and 26 men received an intraduodenal glucose at 3 kcal/min for 60 minutes. Venous blood was sampled every 15 minutes for measurements of blood glucose and plasma insulin, GLP-1 and GIP. Results In response to intraduodenal glucose at 2 kcal/min, the incremental area under the curve between t = 0-60 minutes (iAUC0-60min) for blood glucose and plasma GIP did not differ between the 2 groups. However, iAUC0-60min for plasma GLP-1 (P = 0.016) and insulin (P = 0.011) were ∼2-fold higher in women than men. In response to intraduodenal glucose at 3 kcal/min, iAUC0-60min for blood glucose, plasma GIP, and insulin did not differ between women and men, but GLP-1 iAUC0-60min was 2.5-fold higher in women (P = 0.012). Conclusion Healthy young women exhibit comparable GIP but a markedly greater GLP-1 response to intraduodenal glucose than men. This disparity warrants further investigations to delineate the underlying mechanisms and may be of relevance to the reduced risk of diabetes in premenopausal women when compared to men.

Although intestinal microbial dysbiosis was confirmed to be associated with many chronic diseases and health status through complicated interaction with the host, the effect on gastric cancer was less studied. In this study, we sequenced the 16S rRNA and 18S rRNA genes of fecal bacteria and fungi, respectively, in 134 gastric cancer patients and 58 healthy controls matched by age and gender. Propensity score matching (PSM) was adopted for adjusting diet habits and lifestyle, and 44 patients and 44 healthy controls (matching population) were enrolled. Serum antibody to H. pylori and metabolites of the matching population were detected. The positive rates of antibody to H. pylori between the patients and the control group did not reach the statistical difference. LEfSe analysis indicated that bacteria were more stable than fungi when adjusting diet and lifestyle. Veillonella, Megasphaera, and Prevotella 7 genus and Streptococcus salivarius subsp. Salivarius, Bifidobacterium dentium, and Lactobacillus salivarius species in bacteria were related to the risk of gastric cancer and showed a good diagnostic value in distinguishing the patients from healthy controls. Streptococcus mitis showed a risk effect for gastric cancer; however, the effect turned into be protective after PSM. Serum L-alanine, L-threonine, and methionol were positively associated with Veillonella and Streptococcus and several fungi genus. Overall, our findings indicated that fecal microbiome constitution alteration may be associated with gastric cancer through influencing the amino acid metabolism.

Metamaterials possess attractive electromagnetically left-handed properties yet their nature as an artificial structure rather than a material restricts their further applications. In this article we propose to use Co-based ferromagnetic microwires as periodical metamaterial units interweaved into a fabric to realize a “metacomposite” for steering wave propagation. By introducing ferromagnetic microwires in quartz fabric at three curvatures and periodic lengths, the electromagnetic response and microwave behaviors on both horizontally- and vertically-arranged directions were presented and investigated. Tensile behaviors of metacomposites with different ferromagnetic microwire morphologies were monitored by non-contact full field strain measurement system. At X band (8.2–12.4 GHz), metacomposites containing vertically-arranged ferromagnetic microwires show negative permittivity due to the dielectric resonance of microwire arrays. The dielectric response of metacomposites conformed to Lorentz-oscillator mode, behaving similarly to diluted plasma. When ferromagnetic microwires reached the lowest periodic curved length 2.5 mm with the highest curvature was obtained, the metacomposites presented the maximum microwave absorption of 34% and tensile stress of 273 MPa. The incorporation of ferromagnetic microwires exerts trivial influence on the mechanical properties yet homogenizes the strain and reduces the stress concentration on metacomposites. The metacomposite with a periodic curved length of 7.5 mm has less interweaving points and the highest surface float length, therefore achieving the maximum tensile strength of 458 MPa. The single negative metacomposites containing ferromagnetic microwires are featured with excellent structural properties and amenable microwave left-handed properties in controlling wave-propagating behavior, which is of practical engineering significance in structural health monitoring, sensing and stealth applications.

Many kinds of antibiotics in the environments deeply affect the microbial composition, but their effect on the interactions among the host microbiota is still poorly understood. This study used Bombyx mori as the model organism by feeding the antibiotics-treated mulberry leaf, preliminarily explored the effects of antibiotic exposure on the interaction of bacteria and fungi in the worm’s intestine. Our results showed that the elimination of fungi significantly reduced the bacterial richness and diversity in the worm’s intestine after exposure of anti-fungal amphotericin B, while the elimination of bacteria dramatically increased the richness and diversity of fungi after exposure of anti-bacterial ampicillin-streptomycin. The results revealed the intestinal bacteria and fungi of Bombyx mori were markedly shaped by the mulberry leaf flora. Anti-bacterial antibiotics enhanced the correlation between the host gut fungi and the diet-deriving fungi, while anti-fungal antibiotics weakened the correlation between the host gut bacteria and the diet-deriving bacteria. The data preliminarily established a simple model to explore the effect of antibiotics on the host microbiota interactions, and provided a way for further study on the environmental factors of intestinal bacteria-fungi interaction.

Three-dimensional braided composite has a unique spatial network structure that exhibits the characteristics of high delamination resistance, damage tolerance, and shear strength. Considering the characteristics of braided structures, two types of high-performance materials, namely, aramid and carbon fibers, were used as reinforcements to prepare braided composites with different hybrid structures. In this study, the longitudinal and transverse shear properties of 3D braided hybrid composites were tested to investigate the influences of hybrid and structural effects. The damage characteristics of 3D braided hybrid composites under short beam shear loading underwent comprehensive morphological analysis via optical microscopy, water-logging ultrasonic scanning, and X-ray micro-computed tomography methods. It is shown that the shear toughness of hybrid braided composite has been improved at certain degrees compared with the pure carbon fiber composite under both transverse and longitudinal directions. The hybrid braided composites with aramid fiber as axial yarn and carbon fiber as braiding yarn exhibited the best shear toughness under transverse shear loading. Meanwhile, the composites with carbon fiber as axial yarn and aramid fiber as braiding yarn demonstrated the best shear toughness in the longitudinal direction. Due to the different distribution of axial and braiding yarns, the transverse shear property of hybrid braided structure excels over the longitudinal shear property. The failure modes of the hybrid braided composite under the two loading directions are considerably different. Under transverse loading, the primary failure mode of the composites is yarn fracture. Under longitudinal loading, the primary failure modes are resin fracture and fiber slip. The extensive interfacial effects and the good deformation capability of the hybrid braided composites can effectively prevent the longitudinal development of internal cracks in the pattern, improving the shear properties of braided composites.

Purpose The study aims to explore the characteristic microorganisms of the common tongue coatings in patients with gastric cancer (GC). Methods A total of 115 GC patients were assigned to four groups: White-thin coating (W-thin) group, White-thick coating (W-thick) group, Yellow-thin coating (Y-thin) group and Yellow-thick coating (Y-thick) group. Thirty-five healthy volunteers with White-thin coating were recruit as controls. High-throughput sequencing was used to describe the microbial community of the tongue coatings based on 16S rRNA and 18S rRNA genes. Multi-factors statistical analysis was carried out to present the microbial biomarkers of the tongue coating in GC patients. Results At bacterial phylum level, Saccharibacteria had higher relative abundance in W-thick group than W-thin group, Proteobacteria was more abundant in W-thin group than Y-thick group and less abundant in Y-thick group than Y-thin group. At fungal genus level, Guehomyces and Aspergillus presented to be significantly different among the common tongue coatings. Forteen significantly increased taxa were sorted out as the microbial biomarkers of common tongue coatings by LEfSe and ROC analysis. At species level, bacterial Capnocytophaga leadbetteri and fungal Ampelomyces_sp_IRAN_1 may be the potential biomarkers of W-thin coating, four bacterial species (Megasphaera micronuciformis, Selenomonas sputigena ATCC 35185, Acinetobacter ursingii, Prevotella maculosa) may be the potential biomarkers of W-thick coating. In general, the white coatings held more complex commensal relationship than the yellow coatings. Conclusion The common tongue coating owned characteristic microorganisms and special commensal relationship in the GC patients.

Background: Although oral hygiene and health have long been reported to be associated with increased risk of gastric cancer (GC), the direct relationship of oral microbes with the risk of GC have not been evaluated fully. We aimed to test whether tongue coating microbiome was associated with GC risk. Methods: Pyrosequencing of 16S rRNA gene of tongue coating microbiome was used in 57 newly diagnosed gastric adenocarcinomas and 80 healthy controls. Benjamini-Hochberg (BH) was applied for multiple comparison correction. Co-abundance group (CAGs) analysis was adopted. Results: We found that higher relative abundance of Firmicutes, and lower of Bacteroidetes were associated with increased risk of GC. In genus level, Streptococcus trended with a higher risk of GC, the four other genera (Neisseria, Prevotella, Prevotella7, and Porphyromonas) were found to have a decreased risk of GC. Different from overall GC and non-cardia cancer, Alloprevotella and Veillonella trended with the higher risk of cardia cancer. Finally, we analyzed the microbiota by determining CAGs and six clusters were identified. Except the Cluster 2 (mainly Streptococcus and Abiotrophia), the other clusters had an inverse association with GC. Of them, the Cluster 6 (mainly Prevotella and Prevotella7 etc) had a relatively good classification power with 0.76 of AUC. Conclusion: Microbiome in tongue coating may have potential guiding value for early detection and prevention of GC.

The effects of braided architecture and co-braided hybrid structure on low-velocity response of carbon-aramid hybrid three-dimensional five-directional (3D5d) braided composites were experimentally investigated in this study. Low-velocity impact was conducted on two types of hybridization and one pure carbon fiber braided reinforced composites under three velocities. Damage morphologies after low-velocity impact were detected by microscopy and ultrasonic nondestructive testing. Interior damages of composites were highly dependent on yarn type and alignment. Impact damage tolerance was introduced to evaluate the ductility of hybrid composites. Maximum impact load and toughness changed with impact velocity and constituent materials of the composites. The composite with aramid fiber as axial yarn and carbon fiber as braiding yarn showed the best impact resistance due to the synergistic effect of both materials. Wavelet transform was applied in frequency and time domain analyses to reflect the failure mode and mechanism of hybrid 3D5d braided composites. Aramid fibers were used either as axial yarns or braiding yarns, aiding in the effective decrease in the level of initial damage. In particular, when used as axial yarns, aramid fibers effectively mitigate the level of damage during damage evolution.

Background: Our previous study shows that the empirical formula of Chinese medicine Jianpi-yangwei decoction (JYD) can improve the quality of life in patients with gastric cancer undergoing chemotherapy by increasing beneficial gut bacteria and decreasing harmful bacteria. The present study aims to investigate the effect of JYD on gut fungi in patients with gastric cancer undergoing chemotherapy. Methods: A total of 73 patients with gastric cancer undergoing chemotherapy were recruited. Twenty-nine patients in the chemotherapy group were given standard chemotherapy and 44 patients in the observation group were given JYD plus standard chemotherapy. A control group (55 cases) was recruited from the healthy medical examiners. After 3 months of treatment, life-quality score was evaluated and fecal microbiota was tested by high-throughput sequencing based on the 18S rRNA gene. Results: After treatment, life-quality score in the observation group was significantly lower than that in the chemotherapy group (P < 0.05). There was no significant difference between the observation and control groups’ diversity and richness indices of intestinal fungi. The Chao index for intestinal fungi in the chemotherapy group was significantly lower than that in the observation group (P < 0.05). There was a significant difference between the control and chemotherapy groups in the intestinal fungi according to Shannon and Simpson indices (P < 0.05). Linear discriminant analysis effect size analysis showed no significant differences among the three groups, but significant difference in intestinal fungi was observed between the observation group and the chemotherapy group. At the genus level, the relative abundance of the Aspergillus genus in the observation and control groups was significantly lower (P < 0.05), the relative abundance of the Cutaneotrichosporon, Galactomyces, and Ganoderma genus taxa was significantly higher compared with those in the chemotherapy group (P < 0.05), and there was no significant difference between the observation group and control group. Conclusion: JYD can ameliorate chemotherapy-induced fungal dysbacteriosis in patients with gastric cancer undergoing chemotherapy and improve the quality of life of patients.