[Activation of cannabinoid receptor 2 alleviates acute lung injury in rats with lipopolysaccharide-induced sepsis]

OBJECTIVE

To investigate the protective effect of cannabinoid receptor 2 (CB2) activation against acute lung injury in rats with lipopolysaccharide (LPS)-induced sepsis and explore the underlying mechanism.

METHODS

Forty-eight SD rats were randomly assigned into control group, model group, CB2 agonist group and P38 MAPK inhibitor group (n=12). In the latter 3 groups, the rats received intraperitoneal injection of LPS to induce sepsis, and the control rats were given saline injection. In CB2 agonist group, JWH133 (3 mg/kg) was injected intraperitoneally 30 min before LPS injection; in P38 MAPK inhibitor group, the rats received intraperitoneal injection of SB203580 (5 mg/kg) 30 min prior to JWH133 injection. The changes in lung histopathology, water content, fluid clearance rate, inflammatory factors, pulmonary expressions of CB2 and tight junctionrelated genes, and phosphorylation of P38 MAPK in the lung tissues were examined.

RESULTS

The rat models of sepsis showed severe damage of alveolar structures with significantly decreased fluid clearance rate, lowered pulmonary expressions of CB2, occludin and ZO-1 mRNA and proteins, increased water content in the lung tissue, and increased phosphorylation level of P38 MAPK and TNF-α and IL-1β levels in lung lavage fluid (all P < 0.05). Treatment with JWH133 improved alveolar pathology in the septic rats, but there was still inflammatory infiltration; lung tissue water content, phosphorylation of P38 MAPK, and TNF-α and IL-1β levels in lung lavage fluid were all significantly decreased, and the fluid clearance rate, pulmonary expressions of CB2, occludin and ZO-1 were significantly increased (all P < 0.05). Additional treatment with SB203580 resulted in further improvements of alveolar pathologies, lowered phosphorylation levels of P38 MAPK in the lung tissue and TNF-α and IL-1β levels in lung lavage fluid, and increased the protein expressions of occludin and ZO-1 (P < 0.05) without causing significant changes in mRNA and protein expression of CB2 (P > 0.05).

CONCLUSION

In rats with LPS-induced sepsis, activation of CB2 can inhibit the p38 MAPK signaling pathway, reduce the release of inflammatory factors in the lung tissues, promote tight junction protein expressions, and thus offer protection against acute lung injury.

How well do polygenic risk scores identify men at high risk for prostate cancer? Systematic review and meta-analysis

OBJECTIVES

Genome-wide association studies have revealed over 200 genetic susceptibility loci for prostate cancer (PCa). By combining them, polygenic risk scores (PRS) can be generated to predict risk of PCa. We summarize the published evidence and conduct meta-analyses of PRS as a predictor of PCa risk in Caucasian men.

PATIENTS AND METHODS

Data were extracted from 59 studies, with 16 studies including 17 separate analyses used in the main meta-analysis with a total of 20,786 cases and 69,106 controls identified through a systematic search of ten databases. Random effects meta-analysis was used to obtain pooled estimates of area under the receiver-operating characteristic curve (AUC). Meta-regression was used to assess the impact of number of single-nucleotide polymorphisms (SNPs) incorporated in PRS on AUC. Heterogeneity is expressed as I² scores. Publication bias was evaluated using funnel plots and Egger tests.

RESULTS

The ability of PRS to identify men with PCa was modest (pooled AUC 0.63, 95% CI 0.62-0.64) with moderate consistency (I² 64%). Combining PRS with clinical variables increased the pooled AUC to 0.74 (0.68-0.81). Meta-regression showed only negligible increase in AUC for adding incremental SNPs. Despite moderate heterogeneity, publication bias was not evident.

CONCLUSION

Typically, PRS accuracy is comparable to PSA or family history with a pooled AUC value 0.63 indicating mediocre performance for PRS alone.

[Effects of parity on nutrition and health status of Chinese women of childbearing age]

Objective: To analyze effects of parity on women's nutrition and health status. Methods: This study was based on the data bank of "Chinese Nutrition and Health Surveillance of Children and Adolescents Aged 0-17 years old and Lactating Mothers from 2016 to 2017". Using a multi-stage stratified random sampling method, 17 771 women at 0 to 24 months postpartum from 31 provinces in Mainland China were included in this study. Questionnaires were used to collect data on women's general demographic characteristics, parity, mode of delivery, pre-pregnancy weight, pre-delivery weight, diseases before and during pregnancy, postpartum hemorrhage. Current body height, body weight, waist circumference, and blood pressure were measured. Blood hemoglobin, blood glucose and blood lipids were detected. Pre-pregnancy BMI, gestational weight gain, postpartum weight retention, postpartum BMI, the rates of anemia, hypertension, diabetes, and dyslipidemia were calculated. Survey sample weights were calculated according to the sampling design and number of children under 2 years old from the sixth population census data of China. Effects of parity on the observational indicators after adjusting for confounding factors were analyzed by multivariate linear regression and multivariate logistic regression. Results: The age of 17 771 women was (29.5±5.0) years old, 12.2% (2 172) were over 35 but less than 40 years old, and 3.2% (563) were over 40 years old; the women with one parity, two parities, and three parities accounted for 47.3% (8 413), 48.5% (8 620) and 4.2% (738), respectively; urban women accounted for 49.9% (8 875), and rural women accounted for 50.1% (8 896). The results from multivariate linear regression showed that the pre-pregnancy BMI of women with two and three parities was 0.55 kg/m² and 0.76 kg/m² higher than women with one parity, respectively; the results of multivariate logistic regression showed that the OR(95%CI) of pre-pregnancy anemia was 1.45(1.04-2.02) for women with three parities compared with women with one parity, and the OR(95%CI) of anemia during pregnancy for women with two parities was 1.20(1.06-1.35) compared with women with one parity. Conclusion: Parity is associated with pre-pregnancy BMI and risk of anemia before and during pregnancy in women of reproductive age.

Osteocalcin reduces fat accumulation and inflammatory reaction by inhibiting ROS-JNK signal pathway in chicken embryonic hepatocytes

Osteocalcin (OCN) has a function in preventing fatty liver hemorrhagic syndrome (FLHS) in poultry. The aim of this study was to investigate the effects of OCN on fat emulsion stimulated chicken embryonic hepatocytes and related signaling pathways. The primary chicken embryonic hepatocytes were isolated from the incubated 15-day (E15) pathogen free eggs and cultured with dulbecco's modified eagle medium (DMEM). After the hepatocyte density reached 80%, the cells were divided into 5 groups: control group (CONT), fat emulsion group (FE, 10% FE, v/v), FE with ucOCN at 1 ng/mL (FE-LOCN), 3 ng/mL (FE-MOCN), and 9 ng/mL (FE-HOCN). In addition, 2 mM N-Acetyl-L-cysteine (NAC) a reactive oxygen species (ROS) scavenger, and 5 μM SP600125, a Jun N-terminal kinase (JNK) inhibitor, were added separately in to the DMEM with 10% FE to test effects of FE on the function of ROS-JNK signal pathway. The number of hepatocytes, cell ultra-microstructure, viability, and apoptosis were detected after 48 h treatment, and the protein expressions and enzyme concentrations were detected after 72 h treatment. The results showed that, compared to the control group, FE increased the triglyceride (TG) concentration and lipid droplets (LDs) in chicken embryonic hepatocytes (P < 0.05), and induced hepatocytic edema with obviously mitochondrial swelling, membrane damage, and cristae rupture. FE also decreased ATP concentration, increased ROS concentrations and mitochondrial DNA (mtDNA) copy number, promoted inflammatory interleukin-1 (IL-1), IL-6, tumor necrosis factor-alpha (TNF-α) concentrations and hepatocytic apoptosis rate, and raised phospho-c-Jun N-terminal kinase (p-JNK) protein expressions. Compared to the FE group, ucOCN significantly increased hepatocyte viability, reduced hepatocytic TG concentrations and LDs numbers, and alleviated hepatocytic edema and mitochondrial swelling. Furthermore, ucOCN significantly decreased ROS concentrations, increased ATP concentrations, reduced IL-1, IL-6, TNF-α concentrations and hepatocytic apoptosis rate, and inhibited p-JNK protein expressions (P < 0.05). NAC had the similar functions of ucOCN reduced the ROS concentration and inhibited the TNF-α protein expression and p-JNK/JNK ration. Similarly, SP600125 reduced p-JNK/JNK protein expression, IL-1, IL-6, TNF-α, and TG concentrations without effects on ROS concentration and hepatocytic apoptosis. These results suggest that ucOCN alleviates FE-induced mitochondrial damage, cellular edema, and apoptosis of hepatocytes. These results reveal that the functions of ucOCN in reducing fat accumulation and inflammatory reaction in chicken embryonic hepatocytes are mostly via inhibiting the ROS-JNK signal pathway.

Recent Progress in Fragmentation of Katritzky Salts Enabling Formation of C-C, C-B, and C-S Bonds

Since their discovery in 1970s, Katritzky salts have emerged as one of the most important classes of building blocks for use in organic synthesis and drug discovery. These bulky pyridinium salts derived from alkylamine can readily generate alkyl radical and undergo a variety of organic transformation reactions such as alkylation, arylation, alkenylation, alkynylation, carbonylation, sulfonylation, and borylation. Through these transformations, complexed molecules bearing new C-C, C-B, or C-S bonds can be constructed in easy ways and in simple steps. This review aims to summarize recent advances in these versatile building blocks in well-classified categories. Representative examples and their reaction mechanisms are discussed. The hope is to provide the scientific community with convenient access to collective information and accelerate further research.

[Pathological features related to onco-immunity and their clinical significance of pancreatic ductal adenocarcinoma]

Objective: To investigate the tumor immunity-related pathologic features and clinical significance in pancreatic ductal adenocarcinoma (PDAC). Methods: All pathologic materials and clinical information of 192 PDAC patients from the Cancer Hospital of the University of Chinese Academy of Sciences from January 2010 to December 2020 were collected. The onco-immune microenvironment associated morphologic features were evaluated, and MHC-Ⅰ, PD-L1, CD3, and CD8 expression were detected by immunohistochemistry (IHC). Then the correlation between the factors and their influence on prognosis was analyzed. Results: There were 163 cases of non-specific adenocarcinoma (163/192, 84.90%), 18 cases of adeno-squamous carcinoma (18/192, 9.37%), and 11 cases of other rare subtypes (11/192, 5.73%). Perineural invasion was observed in 110 cases (110/192, 57.29%) and vascular invasion in 86 cases (86/192, 44.79%). There were 84 cases (84/182, 46.15%) with severe chronic inflammation. Tumor infiltrating immune cell numbers (TII-N) were increased in 52 cases (52/192, 27.08%). Lymphocytes and plasma cells were the main infiltrating immune cells in 60 cases (60/192, 31.25%), whereas in 34 cases (34/192, 17.71%) the tumors were mainly infiltrated by granulocytes, and 98 cases (98/192, 51.04%) showed mixed infiltration. CD3+T cells were deficient in 124 cases (124/192, 66.31%). CD8+T cells were deficient in 152 cases (152/192, 79.58%). MHC-Ⅰ expression was down-regulated in 156 cases (156/192, 81.25%), and PD-L1 was positive (CPS≥1) in 46 cases (46/192, 23.96%). Statistical analysis showed that TII-N was negatively correlated with vascular invasion (P=0.035), perineural invasion (P=0.002), stage (P=0.004) and long-term alcohol consumption (P=0.039). The type of immune cells correlated positively with chronic pancreatic inflammation (P=0.002), and negatively with tumor differentiation (P=0.024). CD8+T cells were positively correlated with CD3+T cells (P=0.032), MHC-Ⅰ expression (P<0.001) and PD-L1 expression (P=0.001), and negatively correlated with long-term smoking (P=0.016). Univariate analysis showed that histological nonspecific type (P=0.013) and TII-N (P<0.001) were the factors for good prognosis. Vascular invasion (P=0.032), perineural invasion (P=0.001), high stage (P=0.003) and long-term alcohol consumption (P=0.004) were adverse prognostic factors. COX multivariate risk analysis found that TII-N was an independent favorable factor for PDAC, while perineural invasion was an independent adverse risk factor. Conclusions: TII-N is an independent superior prognostic factor for PDAC, and significantly correlated with many factors; chronic alcohol consumption and smoking may inhibit onco-immunity in PDAC patients.

Recent Advances in Synergistic Antitumor Effects Exploited from the Inhibition of Ataxia Telangiectasia and RAD3-Related Protein Kinase (ATR)

As one of the key phosphatidylinositol 3-kinase-related kinases (PIKKs) family members, ataxia telangiectasia and RAD3-related protein kinase (ATR) is crucial in maintaining mammalian cell genomic integrity in DNA damage response (DDR) and repair pathways. Dysregulation of ATR has been found across different cancer types. In recent years, the inhibition of ATR has been proven to be effective in cancer therapy in preclinical and clinical studies. Importantly, tumor-specific alterations such as ATM loss and Cyclin E1 (CCNE1) amplification are more sensitive to ATR inhibition and are being exploited in synthetic lethality (SL) strategy. Besides SL, synergistic anticancer effects involving ATRi have been reported in an increasing number in recent years. This review focuses on the recent advances in different forms of synergistic antitumor effects, summarizes the pharmacological benefits and ongoing clinical trials behind the biological mechanism, and provides perspectives for future challenges and opportunities. The hope is to draw awareness to the community that targeting ATR should have great potential in developing effective anticancer medicines.

Bacillus subtilis inhibits intestinal inflammation and oxidative stress by regulating gut flora and related metabolites in laying hens

Bacillus subtilis is one of the most popular commercial probiotics used in farm animal production. However, its potential mechanisms are not very clear. The aim of this study was to investigate the effects of dietary Bacillus subtilis on intestinal histomorphology, innate immunity, microbiota composition, transcriptomics, and related metabolomics. Twenty-four 48-week-old Lohman Pink-shell laying hens were randomly divided into two groups: a basic diet and the basic diet supplemented with Bacillus subtilis (0.5 g/kg) for a 9-week experiment. At the end of the experiment, tissues of the duodenum, ileum, and jejunum as well as cecal content of each bird were collected for microstructure, PCR, transcriptome, metabolome, and 16S rRNA analyses. The results showed that dietary Bacillus subtilis supplement had no effect on the intestinal microstructure. However, Bacillus subtilis increased mRNA expression of tight junction protein occludin (P < 0.05), while reduced mRNA expression of lipopolysaccharide-induced TNF factor (P < 0.01) in the duodenum. Moreover, transcriptomic results indicated that most of Bacillus subtilis supplement-induced differential genes were associated with inflammation and immunity, including cytochrome b-245 beta chain, transferrin, and purinergic receptor P2X 7, resulting in a decrease in Malondialdehyde level (P < 0.05) in the duodenum. In addition, at the genus level, Bacillus subtilis supplement enriched the potential beneficial bacteria, Candidatus_Soleaferrea (P = 0.02) but inhibited the harmful bacteria including Lachnospiraceae_FCS020_group, Ruminiclostridium, Lachnospiraceae_UCG-010, and Oxalobacter. Metabolomic results revealed that N-Acetylneuraminic acid and ADP were increased by fed Bacillus subtilis. These results suggest that dietary Bacillus subtilis could inhibit gut inflammation and improve antioxidative status and barrier integrity of the duodenum via regulating gut microbial composition in laying hens.

Response and tolerance mechanism of food crops under high temperature stress: a review

High temperature stress events are critical factors inhibiting crop yield. Meanwhile, world population is growing very rapidly and will be reached up to 9 billion by 2050. To feed increasing world population, it is challenging task to increase about 70% global food productions. Food crops have significant contribution toward global food demand and food security. However, consequences from increasing heat stress events are demolishing their abilities to survive and sustain yield when subjected to extreme high temperature stress. Therefore, there is dire need to better understand response and tolerance mechanism of food crops following exposure to heat stress. Here, we aimed to provide recent update on impact of high temperature stress on crop yield of food crops, pollination, pollinators, and novel strategies for improving tolerance of food crop under high temperature stress. Importantly, development of heat-resistant transgenic food crops can grant food security through transformation of superior genes into current germplasm, which are associated with various signaling pathways as well as epigenetic regulation in response to extreme high temperature stress.

Genetic characterization and clinical characteristics of bovine viral diarrhea viruses in cattle herds of Heilongjiang province, China

BACKGROUND

Heilongjiang province is the main cattle-producing area in China, and molecular epidemiological studies of bovine viral diarrhea viruses (BVDV) in cattle have not been performed in the province.

AIMS

The objective of this research was to determine the genetic and clinical characteristics of BVDV in cattle.

METHODS

Fifty-three BVDV-positive clinical samples were collected from 22 cattle farms in Heilongjiang, and the 5´-untranslated region (5´-UTR) was used to carry out a phylogenetic analysis of the viruses.

RESULTS

The similarity of the 5´-UTR sequences among these BVDVs was 84.2%-100%, and the phylogenetic analysis showed that all viruses belong to the BVDV-1 species, which is classified into five subtypes: BVDV-1b (47.17%, n=25), 1c (15.09%, n=8), 1d (16.98%, n=9), 1 m (3.77%, n=2), and 1o (16.98%, n=9). The statistical results showed that the BVDV-1b subtype had a positive correlation with gastrointestinal disease (P<0.05; 95% CI: 1.19 to 3.34). There were up to three or four BVDV-1 subtypes in some dairy cattle farms, but farms with a single subtype were prevalent (5/10).

CONCLUSION

BVDV-1b is predominant in cattle herds of Heilongjiang province, China, and shows a positive correlation with gastrointestinal disease. BVDV-1o was found for the first time in Chinese cattle, which increased the complex distribution of BVDV-1 subtypes in cattle herds of China.

Races of small molecule clinical trials for the treatment of COVID-19: An up-to-date comprehensive review

The coronavirus disease‐19 (COVID‐19) pandemic has become a global threat since its first outbreak at the end of 2019. Several review articles have been published recently, focusing on the aspects of target biology, drug repurposing, and mechanisms of action (MOAs) for potential treatment. This review gathers all small molecules currently in active clinical trials, categorizes them into six sub‐classes, and summarizes their clinical progress. The aim is to provide the researchers from both pharmaceutical industries and academic institutes with the handful information and dataset to accelerate their research programs in searching effective small molecule therapy for treatment of COVID‐19.

Nickel-catalyzed enantioselective 1,2-vinylboration of styrenes

A novel nickel-catalyzed asymmetric 1,2-vinylboration reaction has been developed to afford benzylic alkenylboration products with high yields and excellent enantioselectivities by using a chiral bisoxazoline ligand. Under optimized conditions, a wide variety of chiral 2-boryl-1,1-arylvinylalkanes are efficiently prepared from readily available olefins and vinyl halides in the presence of bis(pinacolato)diboron as the boron source in a mild and easy-to-operate manner. This three-component cascade protocol furnishes exceptional chemo- and stereoselectivity, and its usefulness is illustrated by its application in asymmetric modifications of several structurally complex natural products and pharmaceuticals.

A novel nickel-catalyzed asymmetric 1,2-vinylboration reaction has been developed to afford benzylic alkenylboration products with high yields and excellent enantioselectivities by using a chiral bisoxazoline ligand.

A survey of a COVID-19 cluster of charter flight importation

OBJECTIVES

Although a number of cases of importation with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been reported, there are still no data available concerning the characteristics in the coronavirus disease 2019 (COVID-19) cluster of charter flight importation. Here, we provide an analysis of COVID-19 cases and their close contacts who worked for the same company on a project in Karbala, Iraq, and returned back to Chengdu, China, by a charter flight.

METHODS

The data of imported COVID-19 cases and their close contacts were obtained from National Notifiable Disease Report System of Chinese Center for Disease Control and Prevention and field epidemiological investigation reports by Centers for Disease Control and Prevention (CDCs) in Chengdu. The information of general characteristics and laboratory findings of this cluster were collected and summarized.

RESULTS

One hundred and six (66.67%) of 159 charter flight passengers tested positive for COVID-19 before entry. Through treatment, all 159 people tested negative and meet the requirements of taking flights bound for China before boarding. However, there has been still 36 (22.64%) of them tested positive after entry. The median time from entry to confirmation was 1.0 day (Interquartile Range (IQR): 0-4.3). The Cycle threshold value (Ct value) of 36 patients' positive samples are all above 30 and most values are above 35.

CONCLUSIONS

In conclusion, there is still a risk that a number of COVID-19 cases can be imported through charter flight. However, the infectivity of confirmed patients of the charter flight was considered to be low.

In Situ Oxygen Generation Enhances the SCAP Survival in Hydrogel Constructs

Prolonged and severe hypoxia is the main cause of death of transplanted cells prior to the establishment of functional circulation. In situ generation of oxygen by oxygen-producing scaffolds-a unique solution that could produce and deliver oxygen to the adjacent cells independently of blood perfusion-has attracted considerable attention to enhance the survivability of the transplanted cells. However, the application of oxygen-generating scaffolds for facilitating cell survival in pulp-like tissue regeneration is yet to be explored. In this study, gelatin methacryloyl (GelMA)-a biocompatible scaffolding material that closely mimics the native extracellular matrix and is conducive to cell proliferation and differentiation-was used to fabricate oxygen-generating scaffolds by loading various concentrations of CaO₂. The CaO₂ distribution, topography, swelling, and pore size of CaO₂-GelMA hydrogels were characterized in detail. The release of O₂ by the scaffold and the viability, spreading, and proliferation of stem cells from apical papilla (SCAPs) encapsulated in the GelMA hydrogels with various concentrations of CaO₂ under hypoxia were evaluated. In addition, cellular constructs were engineered into root canals, and cell viability within the apical, middle, and coronal portions was assessed. Our findings showed that 0.5% CaO₂-GelMA was sufficient to supply in situ oxygen for maintaining the embedded SCAP viability for 1 wk. Furthermore, the 0.5% CaO₂-GelMA hydrogels improved the survivability of SCAPs within the coronal portion of the engineered cellular constructs within the root canals. This work demonstrated that 0.5% CaO₂-GelMA hydrogels offer a potential promising scaffold that enhances survival of the embedded SCAPs in endodontic regeneration.

Nicotinamide improves NAD+ levels to protect against acetaminophen-induced acute liver injury in mice

Acetaminophen (APAP) overdose causes acute liver injury (ALI). Nicotinamide adenine dinucleotide (NAD) is an essential coenzyme, and NAD⁺ is oxidized type which synthesized from nicotinamide (NAM). The present study aimed to investigate the role of NAD⁺ in ALI and protective property of NAM. The mice were subjected to different doses APAP. After 8 hours, the serum activities of alaninetransaminase (ALT) and aspartate aminotransferase (AST), the hepatic NAD⁺ level and nicotinamide phosphoribosyltransferase (NAMPT) expression were determined. Then, the mice were pretreated with NAM (800 mg/kg), the hepatoprotective effects and the key antioxidative molecules were evaluated. Our findings indicated that APAP resulted in remarkable NAD⁺ depletion in a dose-dependent manner accompanied by NAMPT downregulation, and NAM pretreatment significantly elevated the NAD⁺ decline due to upregulation of NAMPT. Moreover, the downregulated Kelch-like ECH-associated protein-1 (Keap1), upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) and its translocation activation after NAM administration were confirmed, which were in accordance with improved superoxide dismutase (SOD) and glutathione (GSH) levels. Finally, NAM dramatically exhibited hepatoprotective effects by reducing the liver index and necrotic area. This study has suggested that APAP impairs liver NAD⁺ level and NAM is able to improve hepatic NAD⁺ to activate antioxidant pathway against APAP-induced ALI.

Breast milk flora plays an important role in infantile eczema: cohort study in Northeast China

AIMS

Infantile eczema, usually coupled with a range of hypersensitive phenotypes, has come into notice with its rising prevalence and unclear pathogenesis. Recent studies show close ties between eczema and an infant's intestinal flora. To gain a further understanding of the interactions between microbiota and eczema, we studied the breast milk flora as a new factor and present the links among breast milk flora, infant intestinal flora and infantile eczema through a cohort study in Northeast China.

METHODS AND RESULTS

Fifty-two families were recruited with either an eczema or healthy infant younger than 6 months. Analysis and predictions using amplicon sequencing of microbiota found that Bifidobacterium and Bacteroidetes were enriched in healthy and eczema infant stools, respectively, consistent with previous reports. For breast milk flora, more 'positive' bacteria such as Akkermansia were enriched in breast milk from healthy infants' mothers. Further, higher bacterial delivery efficiencies were found in pairs of breast milk flora and infants' stool flora of families with eczema infants compared with families with healthy infants. Bacteroidetes, a widely known indicator of eczema, was found delivered more in eczema pairs. Further metagenomic predictions revealed that the breast milk microbiota participated significantly less in metabolism and immune system pathways, particularly in antigen processing and presentation and in Th17 cell-related pathways.

CONCLUSIONS

In conclusion, as with other components of breast milk, the breast milk microbiota closely associates with infants' health via mother-infant bacterial delivery and metabolic functions.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our research aimed to fill the gap between the eczema and breast milk flora and describe the connections among breast milk and intestinal flora and eczema.

2D monochromatic x-ray imaging for beam monitoring of an x-ray free electron laser and a high-power femtosecond laser

In pump-probe experiments with an X-ray Free Electron Laser (XFEL) and a high-power optical laser, spatial overlap of the two beams must be ensured to probe a pumped area with the x-ray beam. A beam monitoring diagnostic is particularly important in short-pulse laser experiments where a tightly focused beam is required to achieve a relativistic laser intensity for generation of energetic particles. Here, we report the demonstration of on-shot beam pointing measurements of an XFEL and a terawatt class femtosecond laser using 2D monochromatic Kα imaging at the Matter in Extreme Conditions end-station of the Linac Coherent Light Source. A thin solid titanium foil was irradiated by a 25-TW laser for fast electron isochoric heating, while a 7.0 keV XFEL beam was used to probe the laser-heated region. Using a spherical crystal imager (SCI), the beam overlap was examined by measuring 4.51 keV Kα x rays produced by laser-accelerated fast electrons and the x-ray beam. Measurements were made for XFEL-only at various focus lens positions, laser-only, and two-beam shots. Successful beam overlapping was observed on ∼58% of all two-beam shots for 10 μm thick samples. It is found that large spatial offsets of laser-induced Kα spots are attributed to imprecise target positioning rather than shot-to-shot laser pointing variations. By applying the Kα measurements to x-ray Thomson scattering measurements, we found an optimum x-ray beam spot size that maximizes scattering signals. Monochromatic x-ray imaging with the SCI could be used as an on-shot beam pointing monitor for XFEL-laser or multiple short-pulse laser experiments.