Solvent-modulated luminescence of carbon dots for ion sensing and fingerprint detection.

Since carbon dots (CDs) with good water solubility are preferred by researchers and biological applications, a hydrothermal method was used to synthesize green fluorescent CDs with an excitation-independent peak at 526 nm using deionized water as the solvent and neutral red as the carbon source. To achieve spectral modulation, the pH of the solvent was adjusted with KOH to obtain orange CDs (O-CDs) in an alkaline environment, with the emission peak red-shifted to 630 nm. The water-soluble CDs were prepared for multidimension sensing as Fe3+ sensing (on/off). Carbon dots dispersed into a silica gel matrix can be used for fingerprint detection of various materials.

Tailored apoptotic vesicles promote bone regeneration by releasing the osteoinductive brake.

Accumulating evidence has demonstrated that apoptotic vesicles (apoVs) derived from mesenchymal stem cells (MSCs; MSC-apoVs) are vital for bone regeneration, and possess superior capabilities compared to MSCs and other extracellular vesicles derived from MSCs (such as exosomes). The osteoinductive effect of MSC-apoVs is attributed to their diverse contents, especially enriched proteins or microRNAs (miRNAs). To optimize their osteoinduction activity, it is necessary to determine the unique cargo profiles of MSC-apoVs. We previously established the protein landscape and identified proteins specific to MSC-apoVs. However, the features and functions of miRNAs enriched in MSC-apoVs are unclear. In this study, we compared MSCs, MSC-apoVs, and MSC-exosomes from two types of MSC. We generated a map of miRNAs specific to MSC-apoVs and identified seven miRNAs specifically enriched in MSC-apoVs compared to MSCs and MSC-exosomes, which we classified as apoV-specific miRNAs. Among these seven specific miRNAs, hsa-miR-4485-3p was the most abundant and stable. Next, we explored its function in apoV-mediated osteoinduction. Unexpectedly, hsa-miR-4485-3p enriched in MSC-apoVs inhibited osteogenesis and promoted adipogenesis by targeting the AKT pathway. Tailored apoVs with downregulated hsa-miR-4485-3p exhibited a greater effect on bone regeneration than control apoVs. Like releasing the brake, we acquired more powerful osteoinductive apoVs. In summary, we identified the miRNA cargos, including miRNAs specific to MSC-apoVs, and generated tailored apoVs with high osteoinduction activity, which is promising in apoV-based therapies for bone regeneration.

Stereoselective assembly of C-oligosaccharides via modular difunctionalization of glycals.

C-oligosaccharides are found in natural products and drug molecules. Despite the considerable progress made during the last decades, modular and stereoselective synthesis of C-oligosaccharides continues to be challenging and underdeveloped compared to the synthesis technology of O-oligosaccharides. Herein, we design a distinct strategy for the stereoselective and efficient synthesis of C-oligosaccharides via palladium-catalyzed nondirected C1-H glycosylation/C2-alkenylation, cyanation, and alkynylation of 2-iodoglycals with glycosyl chloride donors while realizing the difunctionalization of 2-iodoglycals. The catalysis approach tolerates various functional groups, including derivatives of marketed drugs and natural products. Notably, the obtained C-oligosaccharides can be further transformed into various C-glycosides while fully conserving the stereochemistry. The results of density functional theory (DFT) calculations support oxidative addition mechanism of alkenyl-norbornyl-palladacycle (ANP) intermediate with α-mannofuranose chloride and the high stereoselectivity of glycosylation is due to steric hindrance.

Fabrication and characterization of curcumin-loaded nanoparticles using licorice protein isolate from Radix Glycyrrhizae.

Licorice was widely used in food and herbal medicine. In its extract industry, a substantial amount of licorice protein was produced and discarded as waste. Herein, we extracted Licorice Protein Isolate (LPI) and explored its potential as a curcumin nanocarrier. Using a pH-driven method, we fabricated LPI-curcumin nanoparticles with diameters ranging from 129.30 ± 3.21 nm to 75.03 ± 1.19 nm, depending on the LPI/curcumin molar ratio. The formation of LPI-curcumin nanoparticles was primarily driven by hydrophobic interactions, with curcumin entrapped in LPI being in an amorphous form. These nanoparticles significantly enhanced curcumin properties in terms of solubility, photochemical stability, and stability under varying pH, storage, and physiological conditions. Moreover, the loaded curcumin exhibited a 2.58-fold increase in cellular antioxidant activity on RAW 264.7 cells and a 1.86-fold increase in antitumor activity against HepG2 cells compared to its free form. These findings suggested that LPI could potentially serve as a promising novel delivery material.

Evaluation and comparison of efficacy and safety of tirzepatide and semaglutide in patients with type 2 diabetes mellitus: A Bayesian network meta-analysis.

BACKGROUND: As new antidiabetic drugs, tirzepatide (Tir) and semaglutide (Sem) are progressively applied in clinical practice. However, their efficacy and safety profiles have not been comprehensively assessed. Therefore, a Bayesian network meta-analysis was used to evaluate and compare the efficacy and safety of Tir and Sem in treating type 2 diabetes mellitus (T2DM). METHODS: PubMed, EMBASE, Web of Science, Cochrane Library and ClinicalTrials.gov were systematically searched from inception to April 3rd, 2023. Randomized clinical trials (RCTs) comparing the efficacy and safety of Tir and Sem with placebo or the other antidiabetic drugs in treating T2DM were included. The efficacy outcomes included changes in glycated hemoglobin (HbA1c), body weight (BW), body mass index (BMI), and the proportion of participants with HbA1c< 7 %. The safety outcome was the proportion of participants experiencing gastrointestinal adverse events (GIAEs). RESULTS: A total of 38 studies involving 34,166 participants were included. Compared to 1 mg of subcutaneous Sem (Sem SC), 5 mg, 10 mg and 15 mg of Tir demonstrated superior efficacy in reducing HbA1c (mean difference (MD), [95 % CI], -0.22 [-0.40, -0.03] %, -0.42 [-0.60, -0.24] % and -0.53 [-0.71, -0.35] %, respectively) and BW (MD [95 % CI], -1.48 [-2.53, -0.43] kg, -4.00 [-5.05, -2.95] kg and -5.71 [-6.73, -4.68] kg, respectively). Conversely, 7 mg and 14 mg of oral Sem (Sem PO) displayed inferior efficacy in reducing HbA1c (MD [95 % CI], 0.47 [0.26, 0.68] % and 0.35 [0.16, 0.54] %, respectively) and BW (MD [95 % CI], 2.36 [1.24, 3.48] kg and 1.11 [0.10, 2.13] kg). However, 20 mg and 40 mg of Sem PO were non-inferior in reducing HbA1c (MD [95 % CI], 0.13 [-0.29, 0.55] % and 0.01 [-0.38, 0.40] %, respectively) and BW (MD [95 % CI], -0.41 [-2.71, 1.90] kg and -1.32 [-3.58, 0.92] kg). In terms of safety, compared to 1 mg of Sem SC, 5 mg, 10 mg and 15 mg of Tir did not significantly increase the incidence of GIAEs (odd ratio (OR) [95 % CI], 0.70 [0.42, 1.10], 0.87 [0.52, 1.36] and 0.99 [0.60, 1.54], respectively), while 7 mg of Sem PO showed a lower incidence of GIAEs (OR [95 % CI], 0.48 [0.25, 0.83]). Compared to insulin, 0.5 mg of Sem SC, 1 mg of Sem SC, 5 mg of Tir, 10 mg of Tir and 15 mg of Tir displayed better efficacy in lowering HbA1c (MD [95 % CI], -0.40 [-0.63, -0.18] %, -0.69 [-0.90, -0.48] %, -0.91 [-1.10, -0.72] %, -1.11 [-1.30, -0.92] % and -1.22 [-1.41, -1.03] %, respectively) and BW (MD [95 % CI], -5.34[-6.60, -4.09] kg, -6.70 [-7.90,-5.51] kg, -8.18 [-9.27, -7.10] kg, -10.70 [-11.79, -9.61] kg and -12.41 [-13.49,-11.33] kg, respectively). According to the surface under the cumulative ranking curve (SUCRA) value, among all the included interventions, 15 mg of Tir exhibited the most potent effect in reducing HbA1c (99.81 %) and BW (99.98 %), followed by 10 mg of Tir (96.83 % and 95.72 %), 5 mg of Tir (92.88 % and 86.04 %), 1 mg of Sem SC (85.85 % and 74.97 %), 40 mg of Sem PO (83.66 % and 84.31 %), 20 mg of Sem PO (76.98 % and 77.12 %), 300 mg of Can (49.93 % and 60.89 %), insulin (36.38 % and 0.22 %) and 100 mg of Sit (12.28 % and 18.51 %) respectively. Meanwhile, 5 mg, 10 mg, and 15 mg of Tir (48.32 %, 30.96 %, and 21.07 %, respectively), 0.5 mg and 1 mg of Sem SC (33.54 % and 24.77 %, respectively) significantly increased the incidence of GIAEs. CONCLUSION: Both Tir and Sem demonstrated favorable antidiabetic effects and were particularly suitable for T2DM patients who were obese or overweight. Despite a high incidence of GIAEs, their safety profile was deemed acceptable. Tir was the best option among all the included interventions.

Type 1 diabetes and the risk of epilepsy: A meta-analysis.

AIMS/INTRODUCTION: An overrepresentation of epilepsy has been suggested in patients with type 1 diabetes (T1D). This meta-analysis was conducted to evaluate if type 1 diabetes is associated with a higher incidence of epilepsy. MATERIALS AND METHODS: Longitudinal observational studies which are relevant to the purpose of the meta-analysis were screened and obtained by searching PubMed, Embase, and Web of Science databases. Random-effects models were used when significant heterogeneity was observed; otherwise, fixed-effects models were used. RESULTS: Six observational studies involving 10 datasets of 8,001,899 participants were included, with six datasets including children and only one dataset including older people. Among them, 100,414 (1.25%) had type 1 diabetes. During the follow-up duration of 5.4-15.2 years (mean: 9.5 years), 98,644 cases (1.23%) of epilepsy were observed. Compared with participants with normoglycemia, those with type 1 diabetes were shown to have a higher incidence of epilepsy (risk ratio [RR]: 2.41, 95% confidence interval 1.69-3.44, P < 0.001; I2 = 95%) after adjustment of potential confounding variables including age and sex. Subgroup analysis showed consistent results in nested case-control and retrospective cohort studies, and in studies of children, non-elderly adult, and older participants (P for subgroup difference = 0.42 and 0.07). In addition, a stronger association of type 1 diabetes and epilepsy was suggested in studies with follow-up duration <10 years compared with those ≥10 years (RR: 3.34 vs 1.61, P for subgroup difference < 0.001). CONCLUSION: Patients with type 1 diabetes may have a higher risk of epilepsy, which was mainly driven by datasets including children.

The Impact of Evidence-Based Care on Glycemic Control and Pregnancy Outcomes in Diabetic Pregnancies.

Objective: This study investigates the impact of evidence-based care on glucose levels and pregnancy outcomes in patients with gestational diabetes mellitus. Methods: We employed a prospective cohort study design. We selected 120 patients with gestational diabetes admitted to our institution from May 2019 to May 2021. Using a computerized blind selection method, we divided these patients into two groups, each consisting of 60 patients. The control group received conventional care, while the observation group underwent evidence-based care in addition to conventional care. We compared changes in various glucose-related indices, pregnancy outcomes, and patient satisfaction before and after implementing evidence-based care in both groups. Results: Before care, no statistically significant differences were observed in fasting C-peptide levels, HOMA-IR, and HbA1c between the two groups (P > .05). However, after care, the observation group exhibited significantly lower levels of HOMA-IR and HbA1c compared to the control group, with significantly higher fasting C-peptide levels (P < .05). Furthermore, the observation group experienced a lower incidence of various adverse pregnancy outcomes for both mothers and infants when compared to the control group. Patient satisfaction with care was notably higher in the observation group (88.33%) compared to the control group (55.0%), and this difference was statistically significant (P < .05). Conclusions: Evidence-based nursing interventions can effectively enhance daily care for patients with gestational diabetes. These interventions lead to improved blood glucose control, increased patient compliance, reduced incidence of adverse pregnancy outcomes, and ensured the safety of pregnant women and newborns. These outcomes are achieved through disseminating knowledge, structured dietary and exercise plans, and psychological guidance.

Visible-Light-Mediated Synthesis of C-Alkyl Glycosides via Glycosyl Radical Addition and Aryl Migration.

A visible-light-induced glycoarylation of activated olefins has been accomplished. Glycosyl radicals are generated via radical transfer strategies between (TMS)3SiOH and glycosyl bromides. Subsequent radical translocation and rapid 1,4-aryl migration form ß-sugar amide derivatives, and eight types of sugars are compatible with this reaction. Further, the cascade reaction produced a quaternary carbon center with good functional group adaptability and high regioselectivity in mild conditions.

Lack of IFN-γ Receptor Signaling Inhibits Graft-versus-Host Disease by Potentiating Regulatory T Cell Expansion and Conversion.

IFN-γ is a pleiotropic cytokine that plays a controversial role in regulatory T cell (Treg) activity. In this study, we sought to understand how IFN-γ receptor (IFN-γR) signaling affects donor Tregs following allogeneic hematopoietic cell transplant (allo-HCT), a potentially curative therapy for leukemia. We show that IFN-γR signaling inhibits Treg expansion and conversion of conventional T cells (Tcons) to peripheral Tregs in both mice and humans. Mice receiving IFN-γR-deficient allo-HCT showed markedly reduced graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effects, a trend associated with increased frequencies of Tregs, compared with recipients of wild-type allo-HCT. In mice receiving Treg-depleted allo-HCT, IFN-γR deficiency-induced peripheral Treg conversion was effective in preventing persistent GVHD while minimally affecting GVL effects. Thus, impairing IFN-γR signaling in Tcons may offer a promising strategy for achieving GVL effects without refractory GVHD. Similarly, in a human PBMC-induced xenogeneic GVHD model, significant inhibition of GVHD and an increase in donor Tregs were observed in mice cotransferred with human CD4 T cells that were deleted of IFN-γR1 by CRISPR/Cas9 technology, providing proof-of-concept support for using IFN-γR-deficient T cells in clinical allo-HCT.

Learning and Investigation of the Role of Angiotensin-Converting Enzyme in Radiotherapy for Nasopharyngeal Carcinoma.

Ionizing radiation (IR) is an important treatment for nasopharyngeal carcinoma (NPC) that mainly kills tumor cells by producing large amounts of reactive oxygen species (ROS). Intracellular ROS levels affect the sensitivity of tumor cells to IR. Recently, angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin-converting enzyme (ACE) have been found to affect the intracellular levels of ROS. Therefore, we performed a health informatics assessment of ACE in the TCGA database. We explored the effect of ACE in NPC cells. We found that either knockdown of ACE or inhibition of ACE by enalaprilat could decrease ROS levels in NPC cells. Furthermore, knockdown of ACE or inhibition of ACE by enalaprilat could reduce IR-induced ROS levels. ACE knockdown or inhibition reduced IR-induced DNA damage and apoptosis. ACE overexpression increased the level of ROS in NPC cells and further increased sensitivity to IR. These findings indicate that ACE influences the effect of IR by regulating the level of ROS in NPC cells.

Photoredox-Catalyzed N-Directed Regioselective Difluoroalkylation of Unactivated C(sp3)-H Bonds.

We report a redox-neutral, visible-light-mediated difluoroalkylation of unactivated C(sp3)-H bonds in amides via nitrogen-centered radicals triggered intramolecular hydrogen atom transfer. Notably, all types (tertiary, secondary, and primary) of γ-C(sp3)-H bonds displayed excellent reactivity. This methodology presents a facile route for the regioselective introduction of α,α-difluoroketone fragments into organic molecules. Moreover, the resulting gem-difluoroketones can be readily converted to structurally diverse difluoro-containing molecules, offering broad potential applications in medicinal chemistry and chemical biology.

Prevalence of impaired awareness of hypoglycaemia in people with diabetes mellitus: A systematic review and meta-analysis from 21 countries and regions.

AIMS: Impaired awareness of hypoglycaemia (IAH) is a complication of glucose-lowering therapies for diabetes. The purpose of this review was to estimate the pooled prevalence of IAH and unawareness of hypoglycaemia (UAH). METHODS: We searched the major databases from inception to 8 August 2022 and included all cross-sectional and cohort studies reporting IAH prevalence in people with diabetes. A random-effects model was used to pool effect values. Subgroup analysis and meta-regression were used to identify study-level characteristics affecting prevalence. RESULTS: Sixty-two studies from 21 countries published between 2000 and 2022 were included, with 39,180 participants (type 1 diabetes: 19,304 vs. Type 2 diabetes: 14,650). The pooled prevalence was 23.2% (95% CI: 18.4%-29.3%) via the Clarke questionnaire, 26.2% (95% CI: 22.9%-29.9%) via the Gold score, and 58.5% (95% CI: 53.0%-64.6%) via the Pedersen-Bjergaard method, all from studies classified as presenting a moderate and low risk of bias. The prevalence of IAH was generally higher in people with type 1 diabetes than in those with type 2 diabetes and lowest in Europe. Meta-regression results show that the duration of diabetes was a factor influencing the prevalence of IAH. The prevalence of UAH by the Pedersen-Bjergaard method was 17.6 (95% CI: 14.9%-20.3%). CONCLUSIONS: IAH is a prevalent risk event among people with type 1 and type 2 diabetes, showing clinical heterogeneity and regional variability. UAH, an adverse progression of IAH, is also a serious burden. More primary research on the prevalence of IAH is needed in areas with a high diabetes burden.

Aryl-to-Vinyl 1,4-Nickel Migration/Reductive Cross-Coupling Reaction for the Stereoselective Synthesis of Multisubstituted Olefins.

The aryl-to-vinyl nickel 1,4-migration (1,4-Ni migration) reaction has been reported for the first time. The generated alkenyl Ni species undergo a reductive coupling reaction with unactivated brominated alkanes affording a series of trisubstituted olefins. This tandem reaction exhibits mild conditions, a broad substrate scope, high regioselectivity, and excellent Z/E stereoselectivity. A series of controlled experiments have shown that the critical 1,4-Ni migration process is reversible. In addition, the alkenyl nickel intermediates obtained after migration are highly Z/E stereoselective and do not undergo Z/E isomerization. The obtained trace isomerization products are caused by the instability of the product.

Diabetes with kidney injury may change the abundance and cargo of urinary extracellular vesicles.

Background: Urinary extracellular vesicles (uEVs) are derived from epithelia facing the renal tubule lumen in the kidney and urogenital tract; they may carry protein biomarkers of renal dysfunction and structural injury. However, there are scarce studies focusing on uEVs in diabetes with kidney injury. Materials and methods: A community-based epidemiological survey was performed, and the participants were randomly selected for our study. uEVs were enriched by dehydrated dialysis method, quantified by Coomassie Bradford protein assay, and adjusted by urinary creatinine (UCr). Then, they identified by transmission electron microscopy (TEM), nanoparticle track analysis (NTA), and western blot of tumor susceptibility gene 101. Results: Decent uEVs with a homogeneous distribution were finally obtained, presenting a membrane-encapsulated structure like cup-shaped or roundish under TEM, having active Brownian motion, and presenting the main peak between 55 and 110 nm under NTA. The Bradford protein assay showed that the protein concentrations of uEVs were 0.02 ± 0.02, 0.04 ± 0.05, 0.05 ± 0.04, 0.07 ± 0.08, and 0.11 ± 0.15 µg/mg UCr, respectively, in normal controls and in prediabetes, diabetes with normal proteinuria, diabetes with microalbuminuria, and diabetes with macroproteinuria groups after adjusting the protein concentration with UCr by calculating the vesicles-to-creatinine ratio. Conclusion: The protein concentration of uEVs in diabetes with kidney injury increased significantly than the normal controls before and after adjusting the UCr. Therefore, diabetes with kidney injury may change the abundance and cargo of uEVs, which may be involved in the physiological and pathological changes of diabetes.

Maternal antibiotic treatment during pregnancy attenuates the transport and absorption of maternal antibody IgG through TLR4 and TLR2 receptor.

Maternal antibody IgG, the main antibody in colostrum, plays an important role in neonates protection. Commensal microbiota is closely related to host antibody repertoire. However, there are few reports on how maternal gut microbiota affects maternal antibody IgG transfer. In the present study, we investigated the effects of altering the gut microbiota (treated with antibiotics during pregnancy) on maternal IgG transportation and offspring absorption and explored its underlying mechanisms. Results showed that antibiotic treatment during pregnancy significantly decreased maternal cecal microbial richness (Chao1 and Obesrved species) and diversity (Shannon and Simpson). Plasma metabolome enriched significant changes in the process of bile acid secretion pathway, and the concentration of deoxycholic acid, a secondary metabolite of microorganisms was lowered. Flow cytometry analysis indicated that antibiotic treatment promoted the number of B cells and abated the number of T, DC and M1 cells in intestinal lamina propria of dams. Surprisingly, the serum IgG level in antibiotic treated dams was significantly increased, while IgG contents in colostrum was decreased. Moreover, pregnancy antibiotic treatment in dams was reduced the expression of FcRn, TLR4 and TLR2 in breast of dams and in duodenum and jejunum of neonates. Furthermore, TLR4-/- and TLR2-/- knock-out mice showed a lower FcRn expression in breast of dams and in duodenum and jejunum of neonates. These findings suggest that maternal intestine bacteria may affect the maternal IgG transfer through regulating the breast TLR4 and TLR2 of dams.

Fish oil nano-emulsion kills macrophage: Ferroptosis triggered by catalase-catalysed superoxide eruption.

Fish oil is increasingly utilised in the form of nano-emulsion as a nutrient and function fortifier. The nano-emulsions exceptionally high content of polyunsaturated fatty acids and electron donors at the oil/water interface provide an ideal site of the redox reaction. Here we report that a vigorous superoxide production in the fish oil nano-emulsion was catalysed by mammalian catalase in acellular and cellular systems. The resulting superoxide increased cytosolic reactive oxygen species (ROS) and membrane lipid peroxidation of murine macrophage, which eventually causes fatal oxidative damages. Cell death, was significantly inhibited by a catalase-specific inhibitor 3-Amino-1,2,4-triazole (3-AT), was via ferroptosis and not apoptosis. The ferroptosis was independent of free iron or glutathione peroxidase suppression. Our findings discovered a hidden health risk of the widely acclaimed fish oil emulsion, suggesting a novel cellular damage mechanism caused by dietary unsaturated fats on the alimentary tract mucosa.

Enantioselective Synthesis of Both Axially and Planar Chiral Ferrocenes via Axial-to-Planar Diastereoinduction.

Ferrocenes with planar chirality have emerged as an important class of scaffolds for ligands in asymmetric catalysis; however, ferrocene molecules with polychiral structures have not been well explored. Herein, both axially and planar chiral ferrocenes were synthesized via palladium/chiral norbornene cooperative catalysis and axial-to-planar diastereoinduction. In this work, chiral norbornene was used to stereoselectively control the aromatic axial chirality, and further selectivity induced C(sp2)-H activation for ferrocene planar chirality. Based on density functional theory calculations, the catalytic model of chiral norbornene with the substrate and the axial-to-planar diastereoinduction process were confirmed.

Dietary essential oils improves the growth performance, antioxidant properties and intestinal permeability by inhibiting bacterial proliferation, and altering the gut microbiota of yellow-feather broilers.

This experiment was conducted to investigate the antibacterial effects of essential oils (EO) in vitro and the influence of EO on growth performance, intestinal morphology and oxidation resistance and cecal microflora of yellow-feathered broilers. A total of 720 one-day-old male yellow feather broilers were randomly assigned into 4 treatments with 6 replicate cages of 30 broilers each. The groups were as follows: CON group (basal diet), EO200 group (basal diet + 200 mg/kg EO), EO400 group (basal diet + 400 mg/kg EO), and EO600 group (basal diet + 600 mg/kg EO). The experiment lasted for 48 d. Results showed that the growth and biofilm formation of avian pathogenic E. coli O78 and Salmonella pullorum were limited by adding EO to the diet (P < 0.05). Besides, birds fed with EO had greater (P < 0.05) average daily feed intake (ADFI), average daily gain (ADG), and body weight (BW) during d 1 to 21, 22 to 42, and 1 to 48 and lower (P < 0.05) feed: gain (F:G) than those fed with basal diet during d 22 to 42 and 1 to 48. Moreover, the activity of antioxidant enzyme and the intestinal permeability were improved in the EO400 and EO600 groups rather than the CON group on d 21 (P < 0.05). There were significant differences in cecal microbial composition and enrichment of metabolic pathways of birds among all groups by 16S-based sequencing. In summary, some dose of EO improved bacteriostatic ability, antioxidant ability, and intestinal health of broilers which contributed to the growth performance improvement of yellow-feathered broilers, which can be a promising antibiotic alternative for improving poultry production.

Ruthenium-Catalyzed Stereo- and Site-Selective ortho- and meta-C-H Glycosylation and Mechanistic Studies.

C-aryl glycosides are popular basic skeletons in biochemistry and pharmaceutical chemistry. Herein, ruthenium-catalyzed highly stereo- and site-selective ortho- and meta-CAr -H glycosylation is described. A series of C-aryl pyranosides and furanosides were synthesized by this method. The strategy showed good substrate scope, and various N-heterocyclic directing groups were compatible with the reaction system. A mechanistic study suggested that the key pathway of ortho-CAr -H glycosylation might involve oxidative addition/reduction elimination, whereas aryl meta-C-H glycosylation was mediated by σ-activation. Density functional theory calculations also showed that the high stereoselectivity of meta-CAr -H glycosylation was due to steric hindrance.