Seasonal dynamics of the microbiota and nutritional composition in bee bread from Apis cerana and Apis mellifera colonies.

Bee bread is a product of honeybees, which collect and ferment pollen, that contains highly nutritious and easily digestible active substances. However, its nutritional composition varies significantly with fermentation strains and seasonal changes. To unveil the patterns of microbial community and nutritional component changes in bee bread across seasons, we employed high-throughput techniques to assess the diversity of bacteria and fungi in bee bread. The results indicated that the compositions of bacteria and fungi in bee bread undergo significant seasonal variation, with noticeable changes in the microbial diversity of bee bread from different bee species. Subsequently, metabolomic analysis revealed high activity of glycerophospholipid metabolism in bee bread. Furthermore, our analysis identifaied noteworthy differences in nutritional components, including pH values, sugar content, and free amino acid levels, in bee bread across different seasons.

Lipoxin A4 Ameliorates Lipopolysaccharide-Induced A549 Cell Injury through Upregulation of N-myc Downstream-Regulated Gene-1.

BACKGROUND: Lipoxin A4 (LXA4) can alleviate lipopolysaccharide (LPS)-induced acute lung injury (ALI) and acute respiratory distress syndrome through promoting epithelial sodium channel (ENaC) expression in lung epithelial cells. However, how LXA4 promote ENaC expression is still largely elusive. The present study aimed to explore genes and signaling pathway involved in regulating ENaC expression induced by LXA4. METHODS: A549 cells were incubated with LPS and LXA4, or in combination, and analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) of ENaC-α/γ. Candidate genes affected by LXA4 were explored by transcriptome sequencing of A549 cells. The critical candidate gene was validated by qRT-PCR and Western blot analysis of A549 cells treated with LPS and LXA4 at different concentrations and time intervals. LXA4 receptor (ALX) inhibitor BOC-2 was used to test induction of candidate gene by LXA4. Candidate gene siRNA was adopted to analyze its influence on A549 viability and ENaC-α expression. Phosphoinositide 3-kinase (PI3K) inhibitor LY294002 was utilized to probe whether the PI3K signaling pathway was involved in LXA4 induction of candidate gene expression. RESULTS: The A549 cell models of ALI were constructed and subjected to transcriptome sequencing. Among candidate genes, N-myc downstream-regulated gene-1 (NDRG1) was validated by real-time-PCR and Western blot. NDRG1 mRNA was elevated in a dose-dependent manner of LXA4, whereas BOC-2 antagonized NDRG1 expression induced by LXA4. NDRG1 siRNA suppressed viability of LPS-treated A549 cells (treatment vs. control, 0.605 ± 0.063 vs. 0.878 ± 0.083, P = 0.040) and ENaC-α expression (treatment vs. control, 0.458 ± 0.038 vs. 0.711 ± 0.035, P = 0.008). LY294002 inhibited NDRG1 (treatment vs. control, 0.459 ± 0.023 vs. 0.726 ± 0.020, P = 0.001) and ENaC-α (treatment vs. control, 0.236 ± 0.021 vs. 0.814 ± 0.025, P < 0.001) expressions and serum- and glucocorticoid-inducible kinase 1 phosphorylation (treatment vs. control, 0.442 ± 0.024 vs. 1.046 ± 0.082, P = 0.002), indicating the PI3K signaling pathway was involved in regulating NDRG1 expression induced by LXA4. CONCLUSION: Our research uncovered a critical role of NDRG1 in LXA4 alleviation of LPS-induced A549 cell injury through mediating PI3K signaling to restore ENaC expression.

Cyclic deformation leads to defect healing and strengthening of small-volume metal crystals.

When microscopic and macroscopic specimens of metals are subjected to cyclic loading, the creation, interaction, and accumulation of defects lead to damage, cracking, and failure. Here we demonstrate that when aluminum single crystals of submicrometer dimensions are subjected to low-amplitude cyclic deformation at room temperature, the density of preexisting dislocation lines and loops can be dramatically reduced with virtually no change of the overall sample geometry and essentially no permanent plastic strain. This "cyclic healing" of the metal crystal leads to significant strengthening through dramatic reductions in dislocation density, in distinct contrast to conventional cyclic strain hardening mechanisms arising from increases in dislocation density and interactions among defects in microcrystalline and macrocrystalline metals and alloys. Our real-time, in situ transmission electron microscopy observations of tensile tests reveal that pinned dislocation lines undergo shakedown during cyclic straining, with the extent of dislocation unpinning dependent on the amplitude, sequence, and number of strain cycles. Those unpinned mobile dislocations moving close enough to the free surface of the thin specimens as a result of such repeated straining are then further attracted to the surface by image forces that facilitate their egress from the crystal. These results point to a versatile pathway for controlled mechanical annealing and defect engineering in submicrometer-sized metal crystals, thereby obviating the need for thermal annealing or significant plastic deformation that could cause change in shape and/or dimensions of the specimen.

Early amplitude-integrated EEG monitoring 6 h after birth predicts long-term neurodevelopment of asphyxiated late preterm infants.

UNLABELLED: The present study aimed to assess the prognostic value of early amplitude-integrated electroencephalogram (aEEG) in late preterm infants who were born at a gestational age between 34 0/7 and 36 6/7 weeks for the prediction of neurobehavioral development. Late preterm infants (n = 170) with normal, mild, and severe asphyxia underwent continuous recording of aEEG for 4-6 h starting 6-8 h after delivery. The recordings were analyzed for background pattern, sleep-wake cycle (SWC), and seizures. Survivors were assessed at 18 months by neurological examination and Bayley Scales of Infant Development II. The incidence of adverse neurological outcome in the asphyxia group was significantly higher than in the normal group. For late preterm infants in the asphyxia group, abnormal aEEG pattern had a predictive potential of neurological outcomes with sensitivity of 78.57% (specificity, 87.80%; positive predictive value [PPV], 68.75%; negative predictive value [NPV], 92.31%; power, 85.45%). Non-SWC and intermediate SWC significantly were increased (25.45 and 52.73%, respectively) in the asphyxia group vs. the normal group. SWC pattern had neurological prognosis value in the asphyxia group with sensitivity of 64.29% (specificity, 87.80%; PPV, 64.29%; NPV, 87.80%; power, 81.82%). CONCLUSION: Early aEEG patterns are important determinants of long-term prognosis of neurodevelopmental outcome in asphyxiated late preterm infants.

[Effects of recombinant human erythropoietin on serum levels of neuron-specific enolase, S-100ß protein and myelin basic protein in rats following status epilepticus].

OBJECTIVE: This study examined the effect of recombinant human erythropoietin (r-HuEPO) on the serum levels of neuron-specific enolase (NSE), S-100ß protein and myelin basic protein (MBP) in young rats 24 hrs after lithium-pilocarpine-induced status epilepticus (SE) in order to study the potential role of r-HuEPO in epileptic brain damage. METHODS: Forty 19-21-day-old male Sprague-Dawley (SD) rats were randomly divided into four groups (n=10): normal control group, SE, r-HuEPO pretreated-SE and r-HuEPO. SE was induced by lithium-pilocarpine. R-HuEPO (500 IU/kg) was intraperitoneally injected in the r-HuEPO pretreated-SE and r-HuEPO groups 4 hrs before SE. Serum levels of NSE, S-100ß and MBP were determined 24 hrs after the SE event. RESULTS: Serum levels of NSE, S-100ß and MBP in the SE group increased significantly compared with those in the normal control and the r-HuEPO groups (P＜0.05). The r-HuEPO pretreated-SE group showed significantly decreased serum levels of NSE, S-100ß and MBP compared with the SE group (P＜0.05). CONCLUSIONS: r-HuEPO may reduce the expression of NSE, S-100ß and MBP and thus might provide an early protective effect against epileptic brain injury.

ACTH receptor (MC2R) promoter variants associated with infantile spasms modulate MC2R expression and responsiveness to ACTH.

OBJECTIVE: Adrenocorticotropin hormone (ACTH) has been the standard treatment to infantile spasms (IS). However, the mechanism of ACTH therapy is still unclear. ACTH exerts the function via melanocortin 2 receptor (MC2R). Our previous study showed a common 4-single nucleotide polymorphism (SNP) haplotype TCCT at the MC2R promoter was strongly associated with responsiveness to ACTH therapy, where these 4 SNPs [rs1893219, rs1893220, rs2186944, and a novel SNP (T>C)] were mapped at position -853, -759, -7, and -2 bp based on the transcription start site of the MC2R gene. In this study, we further elucidated functional significances of the TCCT haplotype. METHODS: To evaluate whether the TCCT haplotype influences MC2R transcription levels, the luciferase reporter vector was used by a transient transfection. Expression of rat MC2R cDNA driven by the TCCT-carrying or TCCC-carrying promoter was detected by the real-time quantitative reverse transcription-PCR. These assays were performed on cell lines cultured in absence or presence of ACTH. RESULTS: In the baseline, the light intensity of the luciferase reporter assay driven by the TCCT promoter was four times higher than that by the TCCC promoter. The intensity was dramatically increased in the pGL3-TCCT after ACTH stimulation, compared to that in the pGL3-TCCC. MC2R expression assay showed a 5-fold increase in the TCCT promoter in presence of ACTH, compared with that in absence of ACTH. CONCLUSION: The results showed that the haplotype TCCT in MC2R promoter significantly led to increased MC2R expression and strong responses to ACTH, providing evidence of the molecular mechanism of ACTH therapy in IS.

Genetic polymorphisms of MC2R gene associated with responsiveness to adrenocorticotropic hormone therapy in infantile spasms.

BACKGROUND: Infantile spasms is a severe epileptic encephalopathy, which is refractory to conventional antiepileptic drugs. Adrenocorticotropic hormone (ACTH) has been the major therapy for infantile spasms; however, ACTH therapy is ineffective for some patients. The variations in the receptor genes can contribute to antiepileptic drug resistance. This study was to elucidate the possible associations between the variations of the MC2R gene and ACTH responsiveness in patients with infantile spasms. METHODS: We screened for variations in the promoter and coding region of the MC2R gene in 91 Chinese patients with infantile spasms and 94 controls, using PCR and a direct sequencing method. The frequencies of the genotypes, alleles and reconstructed haplotypes were analyzed in the cases and controls. The association between ACTH responsiveness and genetic variations of the MC2R gene was also assessed. RESULTS: Four single nucleotide polymorphisms (SNPs) were identified in the MC2R promoter, one of which was a novel specimen at position-2 from the transcription start site ATT, -2T > C. Three SNPs (rs1893220, rs2186944 and -2T > C) showed a significant difference between the cases and controls (P < 0.05 for all). The frequency of the common TCCT haplotype carrying four-SNP major alleles was significantly lower in the cases (39%) than in the controls (60%) (P = 0.00003). The homozygous carriers of the TCCT haplotype had a much lower relative risk than the non-carriers (RR = 0.42, 95% CI 0.26-0.70, P = 0.0001). ACTH responsiveness was strongly associated with the TCCT haplotype (P = 0.000082). Compared with non-carriers of the TCCT haplotype, the homozygous and heterozygous carriers were more responsive to ACTH therapy (P = 0.0002; P = 0.0003, respectively). CONCLUSIONS: Our results indicated that the TCCT haplotype in the MC2R promoter is strongly associated with the responsiveness of the ACTH therapy performed on patients with infantile spasms. The polymorphisms of the MC2R promoter might be one important factor that influences the efficacy of ACTH therapy on infantile spasms.