[Specific changes in gut microbiota and short-chain fatty acid levels in infants with cow's milk protein allergy]. / ç‰›å¥¶è›‹ç™½è¿‡æ•å©´å„¿è‚ é“èŒç¾¤ç‰¹å¼‚æ€§å˜åŒ–åŠçŸ­é“¾è„‚è‚ªé ¸æ°´å¹³åˆ†æž.

OBJECTIVES: To explore the changes in gut microbiota and levels of short-chain fatty acids (SCFA) in infants with cow's milk protein allergy (CMPA), and to clarify their role in CMPA. METHODS: A total of 25 infants diagnosed with CMPA at Children's Hospital Affiliated to Zhengzhou University from August 2019 to August 2020 were enrolled as the CMPA group, and 25 healthy infants were selected as the control group. Fecal samples (200 mg) were collected from both groups and subjected to 16S rDNA high-throughput sequencing technology and liquid chromatography-mass spectrometry to analyze the changes in gut microbial composition and metabolites. Microbial diversity was analyzed in conjunction with metabolites. RESULTS: Compared to the control group, the CMPA group showed altered gut microbial structure and significantly increased α-diversity (P<0.001). The abundance of Firmicutes, Clostridiales and Bacteroidetes was significantly decreased, while the abundance of Sphingomonadaceae, Clostridiaceae_1 and Mycoplasmataceae was significantly increased in the CMPA group compared to the control group (P<0.001). Metabolomic analysis revealed reduced levels of acetic acid, butyric acid, and isovaleric acid in the CMPA group compared to the control group, and the levels of the metabolites were positively correlated with the abundance of SCFA-producing bacteria such as Faecalibacterium and Roseburia (P<0.05). CONCLUSIONS: CMPA infants have alterations in gut microbial structure, increased microbial diversity, and decreased levels of SCFA, which may contribute to increased intestinal inflammation.

Critical review on the research of chemical structure, bioactivities, and mechanism of actions of Dendrobium officinale polysaccharide.

Dendrobium officinale (Tie-Pi-Shi-Hu) is a precious traditional Chinese medicine (TCM). The principal active components are polysaccharides (DOP), which have a high potency in therapeutic applications. However, limitations in structure analysis and underlying mechanism investigation impede its further research. This review systemically and critically summarises current understanding in both areas, and points out the influence of starch impurities and the role of gut microbiota in DOP research. As challenges faced in studying natural polysaccharide investigations are common, this review contributes to a broader understanding of polysaccharides beyond DOP.

High-grade transformation of head and neck adenoid cystic carcinoma demonstrates distinctive clinicopathological features and an unfavorable prognosis: a matched case-control study of the largest series in China.

PURPOSE: Amidst the rarity of High-grade transformation (HGT) in adenoid cystic carcinoma (ACC), this study offers unprecedented insights into its aggressive nature and clinical implications. METHODS: A 1:1 match comparison between 23 HGT patients and non-HGT counterparts was extracted from 412 ACC cases, focusing on dissecting distinctive clinicopathological features and prognostic outcomes. RESULTS: The predominant sites of HGT were the sinonasal and lacrimal glands (30.4% each). Notably, the solid subtype was the most prevalent pattern within HGT, accounting for 69.6% of cases. Compared to non-HGT, the HGT cohort exhibited significantly higher rates of lymph node metastasis (39.1% vs. 8.7%; P < 0.05), perineural invasion (60.9% vs. 26.1%; P < 0.05), and increased Ki-67 proliferation index (35.0% vs. 10.0%; P < 0.05). Moreover, HGT regions typically showed reduced or absent p63 expression, along with high-grade pathomorphology. HGT was associated with increased recurrence (55.0%) and distant metastasis (78.3%), leading to an average survival of 35.9 months and a 3-years mortality rate of 35.0%. Overall and progression-free survival rates were significantly decreased in the HGT group. CONCLUSION: This study represents the largest single-center cohort of HGT cases to our knowledge, highlighting its frequent occurrence in the sinonasal and lacrimal glands and association with poorer outcomes. The findings support classifying HGT in ACC as Grade 4, reflecting its severity.

An oligosaccharide marker for rapid authentication of edible bird's nest.

Edible bird's nest (EBN) is a popular and expensive food material. The limited supply and great demand result in the use of adulterants. The authenticity concern is raised due to the lack of appropriate quality markers. Herein, this study aims to provide a specific oligosaccharide marker for rapid EBN authentication. Comparing the benzocaine (ABEE)-labeled saccharide profiles of multiple batches of EBN and adulterants indicates seven unique EBN oligosaccharides. The most abundant one, named BNM001, was selected as a marker and characterized to be Neu5Ac (2-3) Gal by MS and NMR spectra. This new oligosaccharide marker enables a rapid authentication of EBN within 10 min. ABEE labelling of this marker further upgraded the accuracy and sensitivity of the LC-qTOF-MS quantitative analysis. The relative marker content was associated with the quality of EBN products. These results suggest a specific and efficient quality marker for rapid authentication of EBN and related products.

Sensory evaluation, chemical structures, and threshold concentrations of bitter-tasting compounds in common foodstuffs derived from plants and maillard reaction: A review.

The bitterness of foodstuffs is often associated with toxicity, which negatively influences product acceptability. However, bitter compounds have many benefits, and a slight bitter taste is sometimes favored. In this review, we summarize the methods used to isolate and evaluate the taste of bitter compounds in different foods. The chemical structures and threshold concentrations of these compounds are also recapped. Although the structures and thresholds of many bitter compounds have been confirmed, further studies are needed to develop detailed bitter-masking strategies and establish the relation between functional groups (hetero-cyclic substituents and bonding types) and taste quality. Furthermore, a comprehensive bitterness database and chemometric data must be provided in order to quickly assess the bitterness of unfamiliar products.

Recent advances in qualitative and quantitative analysis of polysaccharides in natural medicines: A critical review.

Polysaccharides from natural medicines, being safe and effective natural mixtures, show great potential to be developed into botanical drugs. However, there is yet one polysaccharide-based case that has fulfilled the Botanical Guidance definition of a botanical drug product. One of the reasons is the analytical methods commonly used for qualitative and quantitative analysis of polysaccharides fall far behind the quality control criteria of botanical drugs. Here we systemically reviewed the recent advances in analytical methods. A critical evaluation of the strength and weaknesses of these methods was provided, together with possible solutions to the difficulties. Mass spectrometry with or without robust chromatographic separation was increasingly employed. And scientists have made significant progress in simplifying polysaccharide quantification by depolymerizing it into oligosaccharides. This oligosaccharides-based strategy is promising for qualitative and quantitative analysis of polysaccharides. And continuous efforts are still needed to develop a standardized quality control method that is specific, accurate, repeatable, and applicable for analyzing individual components in natural medicine formulas.

Qualitative and Quantitative Analysis of Ejiao-Related Animal Gelatins through Peptide Markers Using LC-QTOF-MS/MS and Scheduled Multiple Reaction Monitoring (MRM) by LC-QQQ-MS/MS.

Donkey-hide gelatin, also called Ejiao (colla corii asini), is commonly used as a food health supplement and valuable Chinese medicine. Its growing popular demand and short supply make it a target for fraud, and many other animal gelatins can be found as adulterants. Authentication remains a quality concern. Peptide markers were developed by searching the protein database. However, donkeys and horses share the same database, and there is no specific marker for donkeys. Here, solutions are sought following a database-independent strategy. The peptide profiles of authentic samples of different animal gelatins were compared using LC-QTOF-MS/MS. Fourteen specific markers, including four donkey-specific, one horse-specific, three cattle-specific, and six pig-specific peptides, were successfully found. As these donkey-specific peptides are not included in the current proteomics database, their sequences were determined by de novo sequencing. A quantitative LC-QQQ multiple reaction monitoring (MRM) method was further developed to achieve highly sensitive and selective analysis. The specificity and applicability of these markers were confirmed by testing multiple authentic samples and 110 batches of commercial Ejiao products, 57 of which were found to be unqualified. These results suggest that these markers are specific and accurate for authentication purposes.

Qualitative and Quantitative Analysis of Edible Bird's Nest Based on Peptide Markers by LC-QTOF-MS/MS.

Edible bird's nest (EBN) is an expensive health food. There are many adulterants in the market. It remains challenging to discriminate EBN from its adulterants due to a lack of high-specificity markers. Besides, the current markers are confined to soluble fraction of EBN. Here, both soluble and insoluble fractions were analyzed by LC-QTOF-MS/MS. A total of 26 high-specificity peptides that were specific to EBN were selected as qualitative authentication markers. Among them, 10 markers can discriminate EBN from common adulterants, 13 markers discriminate white EBN from grass EBN/common adulterants, and 3 markers discriminate grass EBN from white EBN/common adulterants. Three of them, which showed high signal abundance (Peak area ≥ 106) and satisfactory linearity (R2 ≥ 0.995) with EBN references, were selected as the assay marker; and their peptide sequences were confidently identified by searching database/de novo sequencing. Based on these markers, a qualitative and quantitative analytical method was successfully developed and well-validated in terms of linearity, precision, repeatability, and accuracy. The method was subsequently applied to detect EBN products on the market. The results indicated that more than half of EBN products were not consistent with what the merchants claimed.

Transcriptome sequencing and metabolome analysis reveal the mechanism of Shuanghua Baihe Tablet in the treatment of oral mucositis.

Oral mucositis (OM) caused by cancer therapy is the most common adverse reaction in the radiotherapy of head and neck tumors. In severe cases, it can lead to the interruption of treatment, which affects the control of the disease and the quality of life. Shuanghua Baihe Tablet (SBT) is a traditional Chinese medicine (TCM) formula, which is administerd to treat OM in China. It has been clinically effective for more than 30 years, but the underlying mechanism is not completely understood. With the development of multiple omics, it is possible to explore the mechanism of Chinese herbal compound prescriptions. Based on transcriptomics and metabolomics, we explored the underlying mechanism of SBT in the treatment of OM. An OM model of rats was established by 5-FU induction, and SBT was orally administered at dosages of 0.75 and 3 g·kg-1·d-1. In order to search for SBT targets and related metabolites, the dysregulated genes and metabolites were detected by transcriptomics and metabolomics. Immune related indicators such as interleukin-17 (IL-17) and tumor necrosis factor-α (TNF-α) were detected by ELISA. Treg cell disorders was analyzed by flow cytometry. Our results showed that SBT significantly alleviated the symptoms of OM rats and the inflammatory infiltration of ulcer tissues. After SBT administration, inflammatory related metabolic pathways including linoleic acid metabolism, valine, leucine and isoleucine biosynthesis were significantly altered. Furthermore, the production of proinflammatory factors like IL-17 and TNF-α, were also dramatically reduced after SBT administration. Besides, the infiltration degree of Treg cells in the spleen of OM modeling rats was significantly improved by SBT administration, thus maintaining the immune balance of the body. The current study demonstrates that SBT regulates inoleic acid metabolism, glycerophospholipid metabolism and amino acid metabolism, and inhibits IL-17/TNF signal transduction to restore Treg and Th17 cell homeostasis in OM rats, thereby alleviating chemotherapy-induced OM.

Precise medication for tumor patients in the context of mental stress.

Cancer is the leading cause of disease-related death worldwide due to its late diagnosis and poor outcomes. Precision medicine plays an important role in the treatment of tumors. As found for many types of tumors, mental stress plays a vital role in the promotion and progression of tumors. In this paper, we briefly introduce the manifestation and effects of mental symptoms in tumor patients. We next specifically discuss the multiple roles of precision medicine in the tumor therapy. Finally, we also highlight the precision medicine strategy for psychiatric symptoms in tumor patients, which promises to enhance the efficacy of tumor therapy.

A specific and bioactive polysaccharide marker for Cordyceps.

Cordyceps is one of the most expensive and widely used functional foods. But the authenticity is still a concern due to the lack of appropriate markers. By targeting polysaccharides, this study aimed to develop a specific, and bioactive marker for Cordyceps. Firstly, the results of screening tests of 250 samples by examining both genetic markers and polysaccharide profile showed that a unique polysaccharide fraction (named CCP) was particular to the caterpillar parts. Its potential as a marker was further demonstrated by its ability to induce NO and cytokine production in RAW 264.7 cells. CCP was characterized to be an α-1,4-glucan with a branch at C-6 by the conventional structure analyzing and de novo oligosaccharides sequencing. The content of CCP was closely correlated to the traditional classification criteria. Generally, CCP was a marker that simultaneously enables qualitative and quantitative analysis of Cordyceps.

Efficacy and safety of low-dose corticosteroids for acute respiratory distress syndrome: A systematic review and meta-analysis.

BACKGROUND: There are conflicting results regarding whether corticosteroids have better efficacy than placebo in acute respiratory distress syndrome (ARDS) patients. Therefore, we aim to further evaluate the efficacy and safety of corticosteroids in adult ARDS patients. METHODS: The databases, including Medline, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, were searched from their inception to May 2, 2020. Randomized controlled trials (RCTs) and observational cohort studies were selected to assess the use of corticosteroids in adult ARDS patients. The quality of the results was judged by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology. The inverse-variance method with random or fixed effects modeling was used to compute pooled odds ratio (OR), standardized mean difference (SMD), and their 95% confidence interval (CI). RESULTS: Eight eligible RCTs and six cohort studies were included. The use of corticosteroids was associated with reduced mortality (OR 0.57, 95% CI 0.43-0.76, I2=35.1%, P=0.148) in ARDS patients, and the result was confirmed in the included cohort studies (OR 0.51, 95% CI 0.27-0.95, I2=66.7%, P=0.010). The subgroup analysis stratified by the initiation time and duration of corticosteroid use showed that early ARDS and prolonged corticosteroid use had significant survival benefits in the RCTs. The low-dose corticosteroid use was also associated with significantly more ventilator-free days and a reduced rate of new infections in ARDS patients. CONCLUSIONS: The low-dose corticosteroid therapy may be safe and reduce mortality, especially in patients with prolonged treatment and early ARDS.

Over-Expression and Prognostic Significance of FN1, Correlating With Immune Infiltrates in Thyroid Cancer.

BACKGROUND: Thyroid cancer (THCA) is a malignancy affecting the endocrine system, which currently has no effective treatment due to a limited number of suitable drugs and prognostic markers. METHODS: Three Gene Expression Omnibus (GEO) datasets were selected to identify differentially expressed genes (DEGs) between THCA and normal thyroid samples using GEO2R tools of National Center for Biotechnology Information. We identified hub gene FN1 using functional enrichment and protein-protein interaction network analyses. Subsequently, we evaluated the importance of gene expression on clinical prognosis using The Cancer Genome Atlas (TCGA) database and GEO datasets. MEXPRESS was used to investigate the correlation between gene expression and DNA methylation; the correlations between FN1 and cancer immune infiltrates were investigated using CIBERSORT. In addition, we assessed the effect of silencing FN1 expression, using an in vitro cellular model of THCA. Immunohistochemical(IHC) was used to elevate the correlation between CD276 and FN1. RESULTS: FN1 expression was highly correlated with progression-free survival and moderately to strongly correlated with the infiltration levels of M2 macrophages and resting memory CD4+ T cells, as well as with CD276 expression. We suggest promoter hypermethylation as the mechanism underlying the observed changes in FN1 expression, as 20 CpG sites in 507 THCA cases in TCGA database showed a negative correlation with FN1 expression. In addition, silencing FN1 expression suppressed clonogenicity, motility, invasiveness, and the expression of CD276 in vitro. The correlation between FN1 and CD276 was further confirmed by immunohistochemical. CONCLUSION: Our findings show that FN1 expression levels correlate with prognosis and immune infiltration levels in THCA, suggesting that FN1 expression be used as an immunity-related biomarker and therapeutic target in THCA.

Over-Expression and Prognostic Significance of FATP5, as a New Biomarker, in Colorectal Carcinoma.

Background: Fatty acid transporters (FATPs) family play an important role in the uptake and metabolism regulation of long-chain fatty acids, which influence the occurrence and developing of multiple tumors. Fatty acid transporter 5(FATP5), a member of FATPs family, participates in fatty acid transport and lipid metabolism and is related to tumor development, whose mechanism in colorectal cancer (CRC) remains unclear. Methods: In this study, we comprehensively utilized a range of relevant bioinformatic tools along with multiple databases to analyze the expression of FATPs family and investigate the biological function and prognostic value of FATP5 in CRC. Besides, cell proliferation and cell cycle distribution analysis, western blotting and immunohistochemistry (IHC) further validated the conclusion of bioinformatics analysis. Results: FATP5 is the only member of FATPs family which was overexpressed in CRC. In the survival analysis based on the GSE39582 databases, the low expression of FATP5 predicts poor prognosis in CRC. Similar results were also observed in GSE17536, GSE28814 and TCGA colon cohorts. The potential function of DNA methylation regulated the abnormal expression of FATP5 in CRC. In addition, enrichment analysis indicated that FATP5 also participates in the regulation of cell cycle. Furthermore, Gene Set Enrichment Analysis (GSEA) showed a strong negative correlation between FATP5 and cell growth, implying that it may participate in regulating cancer cell proliferation by the regulation of cell cycle G2/M transition. At last, we identified that FATP5 was overexpressed in colorectal carcinoma tissues through immunohistochemistry staining, and played an important role in cell cycle by cell proliferation and cell cycle distribution analysis. Conclusion: This study suggested that FATP5 was overexpression in colorectal carcinoma and predicted favorable prognosis, indicating it as a novel appealing prognostic marker for CRC.

Different iron deposition patterns in akinetic/rigid-dominant and tremor-dominant Parkinson's disease.

OBJECTIVE: The loss of dopaminergic cells and excessive iron deposition in some deep brain nuclei are associated with the pathophysiology of PD, and different clinical subtypes may indicate different pathological processes. This study was designed to investigate the relationships between regional iron in the cardinal subcortical nuclei and different clinical subtypes. PATIENTS AND METHODS: Nine Arkinetic/Rigid-dominant Parkinson's disease (PDAR) patients, eight Tremor-dominant (PDTD)patients and 10 matched healthy controls were recruited for this study. The iron content in 8 cardinal subcortical nuclei was measured through SWI sequence scanning (3.0 T), and different patterns of iron deposition were analyzed not only between the PD patients and HC groups but also between the different clinical subtypes. RESULTS: Compared with the healthy controls, the iron content in the substantia nigra pars compacta(SNc), substantia nigra pars reticulata(SNr) from both the severe and milder side in PD groups were significantly increased (P < 0.01 and P < 0.02 for SNc; both P < 0.01 for SNr), and the iron content in the GP of both the severe and milder side of the PDAR patients was significantly increased compared with the PDTD patients (P < 0.01 and P = 0.02, respectively) CONCLUSION: SWI is a very good technique for the in vivo assessment of subcortical nucleus iron content, and abnormal deposition of iron in the SNc and SNr is an obvious characteristic in PD patients. Furthermore, our data indicates that PDAR patients have higher iron content in the GP than PDTD patients and HCs, indicating that abnormal iron deposition in GP is related to the phenotype of Akinetic/Rigid in PD patients.

Untargeted Metabolomics Analysis of Esophageal Squamous Cell Carcinoma Discovers Dysregulated Metabolic Pathways and Potential Diagnostic Biomarkers.

Background: Esophageal squamous cell carcinoma (ESCC) is one of the most fatal diseases worldwide. Because early diagnosis is difficult, ESCC is mostly diagnosed at an advanced stage, leading to a poor overall prognosis. The purpose of this study was to explore the differences between plasma metabolic profiles in ESCC patients and healthy controls and to establish a diagnostic model of ESCC. Methods: In this study, a cohort of 310 subjects, containing 140 ESCC patients and 170 healthy controls (HC), was recruited. Participants were randomly separated into a training set (80 ESCCs, 80 HCs) and a validation set (60 ESCCs, 90 HCs) and their plasma metabolomics profiles were analyzed by ultra-performance liquid chromatography-tandem quadruple time-of-flight mass spectrometry (UPLC-QTOF/MS) technique. Univariate statistical analysis and multivariate analysis (MVA) methods were used to identify differential metabolites. Finally, the dysregulated pathways associated with ESCC were further explored and the diagnostic performance of the biomarker panel was evaluated. Results: Metabolic analyses identified 34 significant metabolites involved in the metabolism of amino acids, phospholipids, fatty acids, purine, and choline. Farthermore, an effective diagnostic model for ESCC was constructed based on eight metabolites. This panel of biomarkers consisted of hypoxanthine, proline betaine, indoleacrylic acid, inosine, 9-decenoylcarnitine, tetracosahexaenoic acid, LPE (20:4), and LPC (20:5). The model was verified and evaluated in the validation set. The AUC value of the ROC curve was 0.991(95% CI: 0.981-1.000, CI, Confidence interval), with a sensitivity (SE) of 98.8% and a specificity (SP) of 94.9% for the training set and 0.965(95% CI: 0.936-0.993), with a SE of 88.3% and a SP of 88.9% for the validation set. Among them, three biomarkers, indoleacrylic acid, LPC (20:5), and LPE (20:4), exhibited a trend associated with the ESCC progression. Conclusions: Our study identified a novel plasma biomarker panel, which clearly distinguishes ESCC patients and provides insight into the mechanisms of ESCC. This finding may form the basis for the development of a minimally invasive method for ESCC detection.

Case Control Study on Radioactive Stents Versus Conventional Stents for Inoperable Esophageal Squamous Cell Carcinoma.

PURPOSE: The purpose of this study was to compare the relative clinical efficacy of radioactive and normal stent insertion for the treatment of inoperable obstructive esophageal squamous cell carcinoma (OESCC). MATERIALS AND METHODS: Between January 2014 and December 2018, consecutive OESCC patients were treated via either radioactive or normal stent insertion. RESULTS: A total of 42 and 39 OESCC patients were treated via radioactive and normal stent insertion, respectively. These procedures were both technically and clinically successful in all patients. Massive hemorrhage was observed in 7 (16.7%) and 1 (2.6%) patients in radioactive and normal stent groups, respectively (P=0.080). Median stent patency durations were 175 and 136 days in radioactive and normal stent groups, respectively (P=0.004). Median overall survival were 187 and 145 days in the radioactive and normal stent groups, respectively (P=0.011). CONCLUSION: Relative to normal stent, radioactive stents showed a higher patency and overall survival in OESCC patients.

An oligosaccharide-marker approach to quantify specific polysaccharides in herbal formula by LC-qTOF-MS: Danggui Buxue Tang, a case study.

Polysaccharides have broad bioactivities and are major components of water decoction of herb formulae. However, the quality control of polysaccharides remains a challenge. Oligosaccharide-fragment approach has been considered in elucidating chemical structures of polysaccharides, but never been used for quantitation. Using reference chemicals and a real sample Danggui Buxue Tang (DBT) in this study, an oligosaccharide-marker approach was established to quantify specific polysaccharides. Firstly, linear relationships between parent polysaccharides and hydrolysis-produced daughter oligosaccharides were verified using reference polysaccharides. Then in case of DBT, two fluorescence-labeled oligosaccharides with high specificity to individual parent polysaccharides were selected as markers. They were easily isolated and identified. Their potential in quantification of parent polysaccharides were satisfactorily validated in terms of linearity (r≥0.99), repeatability (RSD ≤ 8.4 %), and spike recovery (≥80 %). This method could be a promising approach for quality assessment of polysaccharides in herbal formulae.

Temperature-induced solid-to-solid transformation in helical homochiral coordination polymers.

The reactions of (R)- and (S)-4-(1-carboxyethoxy)benzoic acid (H2CBA) with 1,3-bis(2-methyl-1H-imidazol-1-yl)benzene (1,3-BMIB) ligands afforded a pair of homochiral coordination polymers (CPs), namely, poly[[[µ-1,3-bis(2-methyl-1H-imidazol-1-yl)benzene][µ-(S)-4-(1-carboxylatoethoxy)benzoato]zinc(II)] monohydrate], {[Zn(C10H8O5)(C14H14N4)]·H2O}n or {[Zn{(S)-CBA}(1,3-BMIB)]·H2O}n (1-L), and poly[[[µ-1,3-bis(2-methyl-1H-imidazol-1-yl)benzene][µ-(R)-4-(1-carboxylatoethoxy)benzoato]zinc(II)] monohydrate] (1-D). Three kinds of helical chains exist in compounds 1-D and 1-L, which are constructed from ZnII atoms, 1,3-BMIB ligands and/or CBA2- ligands. When the as-synthesized crystals of 1-L and 1-D were further heated in the mother liquor or air, poly[[µ-1,3-bis(2-methyl-1H-imidazol-1-yl)benzene][µ-(S)-4-(1-carboxylatoethoxy)benzoato]zinc(II)], [Zn(C10H8O5)(C14H14N4)]n or [Zn{(S)-CBA}(1,3-BMIB)]n (2-L), and poly[[µ-1,3-bis(2-methyl-1H-imidazol-1-yl)benzene][µ-(R)-4-(1-carboxylatoethoxy)benzoato]zinc(II)] (2-D) were obtained, respectively. The single-crystal structure analysis revealed that 2-L and 2-D only contained one type of helical chain formed by ZnII atoms and 1,3-BMIB and CBA2- ligands, which indicated that the helical chains were reconstructed though solid-to-solid transformation. This result not only means the realization of helical transformation, but also gives a feasible strategy to build homochiral CPs.

Difficulties in research of Chinese medicine polysaccharides.

Polysaccharides from Chinese medicines are attracting increasing attention to their wide range of valuable biological activities. As these polysaccharides are mostly from edible materials, their safety can be greatly ensured. Therefore, the Chinese medicine polysaccharides have been the focus of research and development of new drugs and health products. However, there are rarely successful cases. Here, based on the authors' own research experience, the difficulties and challenges in chemical analysis and mechanism study of Chinese medicine polysaccharides are discussed, in the hope of eliciting more innovative ideas and solutions.