Clinical efficacy and immune response of neoadjuvant camrelizumab plus chemotherapy in resectable locally advanced oesophageal squamous cell carcinoma: a phase 2 trial.

BACKGROUND: Neoadjuvant immunotherapy is under intensive investigation for esophageal squamous cell carcinoma (ESCC). This study assesses the efficacy and immune response of neoadjuvant immunochemotherapy (nICT) in ESCC. METHODS: In this phase II trial (ChiCTR2100045722), locally advanced ESCC patients receiving nICT were enrolled. The primary endpoint was the pathological complete response (pCR) rate. Multiplexed immunofluorescence, RNA-seq and TCR-seq were conducted to explore the immune response underlying nICT. RESULTS: Totally 42 patients were enrolled, achieving a 27.0% pCR rate. The 1-year, 2-year DFS and OS rates were 89.2%, 64.4% and 97.3%, 89.2%, respectively. RNA-seq analysis highlighted T-cell activation as the most significantly enriched pathway. The tumour immune microenvironment (TIME) was characterised by high CD4, CD8, Foxp3, and PD-L1 levels, associating with better pathological regression (TRS0/1). TIME was categorised into immune-infiltrating, immune-tolerant, and immune-desert types. Notably, the immune-infiltrating type and tertiary lymphoid structures correlated with improved outcomes. In the context of nICT, TIM-3 negatively influenced treatment efficacy, while elevated TIGIT/PD-1 expression post-nICT correlated positively with CD8+ T cell levels. TCR-seq identified three TCR rearrangements, underscoring the specificity of T-cell responses. CONCLUSIONS: Neoadjuvant camrelizumab plus chemotherapy is effective for locally advanced, resectable ESCC, eliciting profound immune response that closely associated with clinical outcomes.

Ripretinib inhibits HIV-1 transcription through modulation of PI3K-AKT-mTOR.

Despite the effectiveness of antiretroviral therapy (ART) in prolonging the lifespan of individuals infected with HIV-1, it does not offer a cure for acquired immunodeficiency syndrome (AIDS). The "block and lock" approach aims to maintain the provirus in a state of extended transcriptional arrest. By employing the "block and lock" strategy, researchers endeavor to impede disease progression by preventing viral rebound for an extended duration following patient stops receiving ART. The crux of this strategy lies in the utilization of latency-promoting agents (LPAs) that are suitable for impeding HIV-1 provirus transcription. However, previously documented LPAs exhibited limited efficacy in primary cells or samples obtained from patients, underscoring the significance of identifying novel LPAs that yield substantial outcomes. In this study, we performed high-throughput screening of FDA-approved compound library in the J-Lat A2 cell line to discover more efficacious LPAs. We discovered ripretinib being an LPA candidate, which was validated and observed to hinder proviral activation in cell models harboring latent infections, as well as CD4+ T cells derived from infected patients. We demonstrated that ripretinib effectively impeded proviral activation through inhibition of the PI3K-AKT-mTOR signaling pathway in the HIV-1 latent cells, thereby suppressing the opening states of cellular chromatin. The results of this research offer a promising drug candidate for the implementation of the "block and lock" strategy in the pursuit of an HIV-1 cure.

Luteolin-7-diglucuronide, a novel PTP1B inhibitor, ameliorates hepatic stellate cell activation and liver fibrosis in mice.

Liver fibrosis, one of the leading causes of morbidity and mortality worldwide, lacks effective therapy. The activation of hepatic stellate cells (HSCs) is the dominant event in hepatic fibrogenesis. Luteolin-7-diglucuronide (L7DG) is the major flavonoid extracted from Perilla frutescens and Verbena officinalis. Their beneficial effects in the treatment of liver diseases were well documented. In this study we investigated the anti-fibrotic activities of L7DG and the potential mechanisms. We established TGF-ß1-activated mouse primary hepatic stellate cells (pHSCs) and human HSC line LX-2 as in vitro liver fibrosis models. Co-treatment with L7DG (5, 20, 50 µM) dose-dependently decreased TGF-ß1-induced expression of fibrotic markers collagen 1, α-SMA and fibronectin. In liver fibrosis mouse models induced by CCl4 challenge alone or in combination with HFHC diet, administration of L7DG (40, 150 mg·kg-1·d-1, i.g., for 4 or 8 weeks) dose-dependently attenuated hepatic histopathological injury and collagen accumulation, decreased expression of fibrogenic genes. By conducting target prediction, molecular docking and enzyme activity detection, we identified L7DG as a potent inhibitor of protein tyrosine phosphatase 1B (PTP1B) with an IC50 value of 2.10 µM. Further studies revealed that L7DG inhibited PTP1B activity, up-regulated AMPK phosphorylation and subsequently inhibited HSC activation. This study demonstrates that the phytochemical L7DG may be a potential therapeutic candidate for the treatment of liver fibrosis.

Discovery of a selective TRF2 inhibitor FKB04 induced telomere shortening and senescence in liver cancer cells.

Telomere repeat binding factor 2 (TRF2), a critical element of the shelterin complex, plays a vital role in the maintenance of genome integrity. TRF2 overexpression is found in a wide range of malignant cancers, whereas its down-regulation could cause cell death. Despite its potential role, the selectively small-molecule inhibitors of TRF2 and its therapeutic effects on liver cancer remain largely unknown. Our clinical data combined with bioinformatic analysis demonstrated that TRF2 is overexpressed in liver cancer and that high expression is associated with poor prognosis. Flavokavain B derivative FKB04 potently inhibited TRF2 expression in liver cancer cells while having limited effects on the other five shelterin subunits. Moreover, FKB04 treatment induced telomere shortening and increased the amounts of telomere-free ends, leading to the destruction of T-loop structure. Consequently, FKB04 promoted liver cancer cell senescence without modulating apoptosis levels. In corroboration with these findings, FKB04 inhibited tumor cell growth by promoting telomeric TRF2 deficiency-induced telomere shortening in a mouse xenograft tumor model, with no obvious side effects. These results demonstrate that TRF2 is a potential therapeutic target for liver cancer and suggest that FKB04 may be a selective small-molecule inhibitor of TRF2, showing promise in the treatment of liver cancer.

Inhibiting the CB1 receptor in CIH-induced animal model alleviates colon injury.

Obstructive sleep apnea (OSA) can lead to intestinal injury, endotoxemia, and disturbance of intestinal flora. Additionally, as a crucial component of the endocannabinoid system, some studies have demonstrated that cannabinoid 1 (CB1) receptors are closely linked to the multiple organ dysfunction triggered by OSA. However, the role of the CB1 receptor in alleviating OSA-induced colon injury remains unclear. Here, through the construction of the OSA classic model, we found that the colon tissue of chronic intermittent hypoxia (CIH)-induced mice exhibited an overexpression of the CB1 receptor. The results of hematoxylin-eosin staining and transmission electron microscopy revealed that inhibition of the CB1 receptor could decrease the gap between the mucosa and muscularis mucosae, alleviate mitochondrial swelling, reduce microvilli shedding, and promote the recovery of tight junctions of CIH-induced mice. Furthermore, CB1 receptor inhibition reduced the levels of metabolic endotoxemia and inflammatory responses, exhibiting significant protective effects on the colon injury caused by CIH. At the molecular level, through western blotting and real-time polymerase chain reaction techniques, we found that inhibiting the CB1 receptor can significantly increase the expression of ZO-1 and Occludin proteins, which are closely related to the maintenance of intestinal mucosal barrier function. Through 16S rRNA high-throughput sequencing and short-chain fatty acid (SCFA) determination, we found that inhibition of the CB1 receptor increased the diversity of the microbial flora and controlled the makeup of intestinal flora. Moreover, butyric acid concentration and the amount of SCFA-producing bacteria, such as Ruminococcaceae and Lachnospiraceae, were both markedly elevated by CB1 receptor inhibition. The results of the spearman correlation study indicated that Lachnospiraceae showed a positive association with both ZO-1 and Occludin but was negatively correlated with the colon CB1 receptor, IL-1ß, and TNF-α. According to this study, we found that inhibiting CB1 receptor can improve CIH-induced colon injury by regulating gut microbiota, reducing mucosal damage and promoting tight junction recovery. KEY POINTS: •CIH leads to overexpression of CB1 receptor in colon tissue. •CIH causes intestinal flora disorder, intestinal mucosal damage, and disruption of tight junctions. •Inhibition of CB1 receptor can alleviate the colon injury caused by CIH through regulating the gut microbiota, reducing mucosal injury, and promoting tight junction recovery.

Physiological and Biochemical Properties of Cotton Seedlings in Response to Cu2+ Stress.

Copper(II) (Cu2+) is essential for plant growth and development. However, high concentrations are extremely toxic to plants. We investigated the tolerance mechanism of cotton under Cu2+ stress in a hybrid cotton variety (Zhongmian 63) and two parent lines with different Cu2+ concentrations (0, 0.2, 50, and 100 µM). The stem height, root length, and leaf area of cotton seedlings had decreased growth rates in response to increasing Cu2+ concentrations. Increasing Cu2+ concentration promoted Cu2+ accumulation in all three cotton genotypes' roots, stems, and leaves. However, compared with the parent lines, the roots of Zhongmian 63 were richer in Cu2+ and had the least amount of Cu2+ transported to the shoots. Moreover, excess Cu2+ also induced changes in cellular redox homeostasis, causing accumulation of hydrogen peroxide (H2O2) and malondialdehyde (MDA). Conversely, antioxidant enzyme activity increased, while photosynthetic pigment content decreased. Our findings indicated that the hybrid cotton variety fared well under Cu2+ stress. This creates a theoretical foundation for the further analysis of the molecular mechanism of cotton resistance to copper and suggests the potential of the large-scale planting of Zhongmian 63 in copper-contaminated soils.

Prognostic value of circulating tumor cells and its association with the expression of cancer stem cells in nasopharyngeal carcinoma patients.

The release of circulating tumor cells (CTCs) into vasculature is an early event in the metastatic process and the detection of CTCs has been widely used clinically. In addition, cancer stem cells (CSCs) are the source of distant metastasis. However, the relationship between CTCs and CSCs in nasopharyngeal carcinoma (NPC) patients was largely unknown. A total of 93 NPC patients were enrolled in this study. The CTCs in the peripheral blood were detected. The expression of ALDH1A1 in the tumor tissues of the corresponding patients was detected using immunohistochemistry (IHC). The prognostic value of CTCs level and the correlation with the expression of ALDH1A1 was evaluated. Data showed that the detection of CTCs was positively correlated with metastasis (p<0.001). The positive detection of CTCs was also associated with poor overall survival (p=0.025). CTCs ≥2 demonstrated good specificity and sensitivity in predicting distant metastasis, while CTCs ≥8 demonstrated better specificity and sensitivity in predicting prognosis than CTCs ≥2. Furthermore, we found that there was a positive relationship between the detection of CTCs and the expression of ALDH1A1 (p=0.001). The prognosis analysis also demonstrated that high ALDH1A1 expression was correlated with poor overall survival (p=0.006). Our study demonstrated a positive correlation between the CTCs and the expression of CSCs, both were positively correlated with metastasis and poor prognosis. These results indicated that the CTCs might indirectly reflect the expression of CSCs.

[Mechanism of oxymatrine in treatment of collagen-induced arthritis in mice].

Sophorae Flavescentis Radix, the root of Sophora flavescens Ait., has been widely applied in the medical field due to its anti-inflammatory, analgesic, bacteriostatic, antiviral, antitumor, and other pharmacological effects. The present study investigated the anti-rheumatoid arthritis effect of oxymatrine(OMT), the active component of Sophorae Flavescentis Radix by observing its effect on the function of B lymphocytes in collagen-induced arthritis(CIA) mice through the Toll-like receptor 9(TLR9)/myeloid differentiation factor 88(MyD88)/signal transducer and activator of transcription 3(STAT3) pathway. The CIA model in DBA/1 J mice was induced by bovine type Ⅱ collagen and complete Freund's adjuvant(CFA). Fifteen days after the primary immunization, mice were treated with OMT for 30 days by intraperitoneal injection. Paw swelling and arthritis index(AI) score were evaluated every 3 days. Joint histopathologic changes were observed by HE staining. Magnetic-activated cell sorting(MACS) was used to isolate B lymphocytes from the spleen of CIA mice spleen. The serum expression level of interleukin(IL)-21 was examined by the enzyme-linked immunosorbent assay(ELISA). The expression of TLR9, STAT3, p-STAT3, and IL-21 in B lymphocytes was detected by Western blot. The mRNA expression of TLR9, STAT3, and IL-21 in B lymphocytes was detected by real-time fluorescence-based quantitative PCR(qRT-PCR). The results showed that OMT could significantly alleviate the paw swelling, decrease the AI score, relieve synovial inflammatory cell infiltration and hyperplasia, reduce the level of inflammatory cytokines, and inhibit the expression of TLR9, STAT3, p-STAT3, and IL-21 of B lymphocytes in CIA mice. Therefore, OMT may alleviate rheumatoid arthritis by regulating TLR9/MyD88/STAT3 pathway in B lymphocytes, providing a valuable reference for the application of OMT in the clinical treatment of rheumatoid arthritis.

Spirobiflavonoid stereoisomers from the endangered conifer Glyptostrobus pensilis and their protein tyrosine phosphatase 1B inhibitory activity.

Six spirobiflavonoid stereoisomers including two new ones, spiropensilisols A (1) and B (2), were isolated from a mass-limited trunk barks of Glyptostrobus pensilis, an endangered conifer endemic to China. The new structures featuring a benzofuran-containing spirolactone and their absolute configurations were determined by extensive spectroscopic methods. All the isolates showed significant inhibitory activities against the human protein tyrosine phosphatase 1B (PTP1B) enzyme, a potential therapeutic target for diabetes and obesity, with IC50 values ranging from 3.3 to 17.1 µM. A preliminary SAR analysis with assistance of the molecular modeling approach was performed for the most potent compound (i.e., 1), to understand the nature of interactions governing the binding mode of spirobiflavonids within the active site of the PTP1B enzyme.

[Anti-tumor effect and its related mechanisms of cinobufotalin combined with cisplatin on H22 liver cancer mice].

In order to observe the anti-tumor effect of cinobufotalin on H22 liver cancer mice and to explore its regulatory mechanism, 50 Kunming mice were subcutaneously inoculated with H22 intraperitoneal passage cells under the armpit to establish H22 hepatocellular carcinoma model. They were then randomly divided into model group, cinobufotalin low dose group, cinobufotalin high dose group, cisplatin group and cisplatin+cinobufotalin group, which received 0.01% ethanol solution, 1 mg·kg~(-1) cinobufotalin, 5 mg·kg~(-1) cinobufotalin, 5 mg·kg~(-1) cisplatin, 5 mg·kg~(-1)cisplatin + 5 mg·kg~(-1) cinobufotalin respectively for 10 days. The general condition of mice during the intervention was observed, and the inhibition rate, tumor mass, thymus index, histopathological changes of the tumors, apoptotic rate of the tumors, the expressions of phosphatidylinositol 3-kinase(PI3 K), protein kinase B(Akt), apoptosis related gene(Fas), Fas ligand(FasL) mRNA and protein phosphorylated Akt(pAkt) protein in the tumors of each group were compared. The results showed that during the modeling period, the mice showed a decline in food intake, dark fur, poor mental status, and gradually worsened over time. The mental status of mice in each intervention group was improved gradually, especially in the cisplatin+cinobufotalin group. As compared with the model group, the tumor mass of each intervention group was lower(P<0.05). As compared with the cinobufotalin low dose group, the tumor mass was lower and inhibition rate was higher in the cinobufotalin high dose group, cisplatin group and cisplatin+cinobufotalin group(P<0.05). As compared with the cinobufotalin high dose group and the cisplatin group, the tumor mass was lower and the inhibition rate was higher in cisplatin+cinobufotalin group(P<0.05). As compared with the model group, the thymus index was higher in cinobufotalin high dose group and cisplatin + cinobufotalin group, while was lower in cisplatin group(P<0.05). As compared with the cinobufotalin low dose group, the thymus index was higher in the cinobufotalin high dose group and lower in the cisplatin group(P<0.05). As compared with the cinobufotalin high dose group, the thymus index was lower in cisplatin group(P<0.05). As compared with cisplatin group, the thymus index was higher in cisplatin+cinobufotalin group(P<0.05). Pathological staining showed that a large number of heterogeneous cells and mitotic phenomena were observed in the model group. Cell fragments and neutrophils were observed in the tumor tissues of the intervention groups, showing diffuse necrosis, and the diffuse necrosis was more obvious in the cisplatin+cinobufotalin group. As compared with the model group, the apoptotic rate of the tumors and the relative expressions of Fas mRNA and protein were higher in the intervention groups, while the relative expressions of PI3 K, FasL mRNA and protein and the relative expression of pAkt protein were lower in the intervention groups(P<0.05). As compared with the cinobufotalin low dose group, the apoptotic rate of the tumors and relative expression of Fas and protein were higher in the cinobufotalin high dose group, cisplatin group and cisplatin+cinobufotalin group, while the relative expressions of PI3 K, FasL mRNA and protein and pAkt protein were lower(P<0.05). As compared with the cinobufotalin high dose group and the cisplatin group, apoptotic rate of the tumors and the relative expression of Fas mRNA and protein were higher in the cisplatin+cinobufotalin group, while the relative expressions of PI3 K, FasL mRNA and protein and pAkt protein were lower in the cisplatin+cinobufotalin group(P<0.05). In summary, cinobufotalin has significant anti-tumor effect on H22 liver cancer mice, and can enhance the immune function of mice and synergistically enhance the effect of chemotherapy. Its mechanism may be associated with regulating PI3 K/Akt/Fas/FasL signaling pathway related genes and protein expression.

MiR-19a enhances cell proliferation, migration, and invasiveness through enhancing lymphangiogenesis by targeting thrombospondin-1 in colorectal cancer.

Colorectal cancer (CRC) is a devastating disease with high mortality and morbidity, and the underlying mechanisms of miR-19a in CRC are poorly understood. In our study, dual-luciferase reporter assays were used to evaluate the binding of miR-19a with thrombospondin-1 (THBS1). Cell viability, migration, and invasiveness were assessed using MTT, wound healing, and Transwell assays, respectively. Tube-formation assays with human lymphatic endothelial cells (HLECs) were used to evaluate lymphangiogenesis, and tumor xenograft assays were used to measure tumor growth. The results showed that miR-19a was up-regulated and THBS1 was down-regulated in CRC tissues and cells. Applying an inhibitor of miR-19a suppressed survival, migration, and invasiveness, and inhibited the expression of matrix metallopeptidase 9 (MMP-9) and vascular endothelial growth factor C (VEGFC). Further mechanistic study identified that THBS1 is a direct target of miR-19a. THBS1 silencing attenuated the above-mentioned suppressive effects induced with the miR-19a inhibitor. Furthermore, the miR-19a inhibitor suppressed the migration and tube-formation abilities of HLECs via targeting the THBS1-MMP-9/VEGFC signaling pathway. And the inhibition of miR-19a also suppressed tumor growth and lymphatic tube formation in vivo. In conclusion, miR-19a inhibition suppresses the viability, migration, and invasiveness of CRC cells, and suppresses the migration and tube-formation abilities of HLECs, and further, inhibits tumor growth and lymphatic tube formation in vivo via targeting THBS1.

Rice vegetative organs alleviate cadmium toxicity by altering the chemical forms of cadmium and increasing the ratio of calcium to manganese.

Altering Cd chemical form is one of the mechanisms to alleviate Cd toxicity in rice plant. Field experiments were carried out in this study to investigate the potential of rice vegetative organs in altering Cd into insoluble chemical forms in the natural environment. Experimental results showed that more than 80% of Cd in rice roots existed in the insoluble forms. Uppermost nodes altered Cd into insoluble form preferentially and generally had higher content of insoluble Cd than other organs. Rachises displayed a slow increasing trend in soluble Cd when total Cd in roots was less than 1.8 mg kg-1. However, when Cd content in roots exceeded 2.8 mg kg-1, the ratio of insoluble to soluble Cd remained stable at 85:15 in rachises and roots, and at 75:25 in uppermost nodes and flag leaves. Cd concentration in grains was greatly lower than that in vegetative organs, and closely correlated with the content of soluble Cd in rachises (r = 0.991**) as well as in uppermost nodes. Soluble Cd in the uppermost nodes displayed a much lower mobility than that in other organs. Accumulation of soluble Cd was always companied by decrease of Ca and increase of Mn in roots, uppermost nodes and rachises. A small increase of soluble Cd from 0.05 to 0.1 mg kg-1 caused a sharp decline of Ca:Mn ratio in roots and rachises. Roots and nodes had much higher Ca:Mn ratio than rachises when soluble Cd was less than 0.5 mg kg-1 in them. These results indicate that vegetative organs have a great potential to alter more than 75% Cd into insoluble forms and increasing Ca:Mn ratio may be another way to alleviate Cd toxicity by establishing new ionic homeostasis in rice plants.

[The Effects of PKCι on Anti-tumor Activity of Cytokine-induced Killer Cells Against Pancreatic Cancer Cells and the Possible Underlying Mechanisms].

OBJECTIVE: To study the impact of atypical protein kinase Cι (PKCι) isoform PKC on the pancreatic cancer cells towards the tumoricidal effect of cytokine-induced killer (CIK) cells and explore its mechanisms. METHODS: CIK cells were prepared by inducing mononuclear cells isolated from the peripheral blood of healthy people with interleukin-2 (IL-2), interferon (IFN) and CD3 mAb and subsequently co-cultured with pancreatic epithelial cell HPDE6-C7, pancreatic cancer cells MiaPaCa and PANC-1 with or without PKC inhibitor named sodium thiomalate (ATM). All cells were divided into control group, ATM group, co-culture group with CIK and co-culture group with CIK+ATM. Cell count was used to detect the growth of each group from 1 to 8 d. Flow cytometry was used to detect the death rate of the cell lines after 48 h cell culture in each group. The small hairpin RNA (shRNA) was used for PKCι knockdown and the recombinant plasmid transfection was for PKCι overexpression in pancreatic cancer cells. Western blot and real-time fluorescent quantitative PCR (qRT-PCR) were utilized to determine the expression of PKCι protein and the impact on gene expression of transforming growth factor-ß (TGF-ß), a downstream effector modulated by PKC. Different mass concentrations of TGF-ß (1, 10, 20 ng/mL) were added into the co-culture of MiaPaCa and PANC-1 with CIK. The cell death rate was detected by flow cytometry 48 h later, so as to explore the possible mechanisms of the impact of PKCι on the tumoricidal effects of CIK cells. RESULTS: ATM and CIK were shown to suppress the growth and induce apoptosis or death of pancreatic cancer cells, meanwhile, ATM can enhance the tumoricidal effect of CIK on pancreatic cancer cells. Moreover, we found that PKCι knockdown in pancreatic cancer cells can down-regulate the gene expression of TGF-ß. In return, PKCι overexpression in pancreatic cancer cells can increase the gene expression of TGF-ß. The death rate of cancer cells with 10, 20 ng/mL TGF-ß was lower compared with the control group (P < 0.05). CONCLUSIONS: PKCι knockdown in pancreatic cancer cells can not only inhibit the growth of pancreatic cancer cells, but also enhance the tumoricidal effects of CIK on cancer cells. The possible mechanism of PKCι is to affect the immune escape of tumor cells by regulating the expression of TGF-ß.

Enantiomeric Pairs of Meroterpenoids with Diverse Heterocyclic Systems from Rhododendron nyingchiense.

Eight enantiomeric pairs of new meromonoterpenoids (1a/1b-8a/8b) and four known compounds (9-12) were isolated from Rhododendron nyingchiense. Their structures were established by spectroscopic methods, quantum chemical calculations, and X-ray crystallography. The enantiomeric pairs were acquired from scalemic mixtures by chiral-phase HPLC and showed diverse heterocyclic frameworks. Compounds 1a/1b possess a rare 6/7/5/5 heterocyclic system, and 2a/2b incorporate a new 6/6/3/5 heterocyclic system featuring a quinone motif. Compounds 3a/3b represent the first meroterpenoids with a 6/6/5 ring system from the Rhododendron genus. Putative biosynthetic pathways of these compounds are proposed. Compounds 1b, 2a-4a, 8a, 8b, and 11 exhibited weak inhibitory effects on PTP1B, with IC50 values ranging from 5.7 ± 0.5 to 61.0 ± 4.8 µM.

Structurally Diverse Sesquiterpenoids from the Endangered Ornamental Plant Michelia shiluensis.

A preliminary phytochemical investigation on the MeOH extract of the leaves and twigs of the endangered ornamental plant Michelia shiluensis led to the isolation of 16 sesquiterpenoids. The isolated compounds comprised germacrane- (1-4, 13, 14), guaiane- (5-9, 15), amorphane- (10), and eudesmane-type (11, 12, 16) sesquiterpenoids. The new structures (1-12) were elucidated by spectroscopic and computational methods, and their absolute configurations (except for 9) were assigned by single-crystal X-ray diffraction crystallographic data and/or electronic circular dichroism spectra. Shiluolides (A-D, 1-4) are unprecedented C16 or C17 homogermacranolides, and their putative biosynthetic pathways are briefly discussed. Shiluone D (8) is a rare 1,10- seco-guaiane sesquiterpenoid featuring a new ether-containing spirocyclic ring, whereas shiluone E (9) represents the first example of a 1,5-4,5-di- seco-guaiane with a rare 5,11 -lactone moiety. Shiluone F (10) is the first amorphane-type sesquiterpenoid possessing an oxetane ring bridging C-1 and C-7. Bioassay evaluations indicated that lipiferolide (13) showed noteworthy cytotoxicities toward human cancer cell lines MCF-7 and A-549, with IC50 values of 1.5 and 7.3 µM, respectively. Shiluone D (8) exerted inhibition against protein tyrosine phosphatase 1B (IC50: 46.3 µM).

[The Influence of New Medium with RGD on Cell Growth,Cell Fusion and Expression of Exogenous Gene].

OBJECTIVE: To investigate the influence of a new culture medium added with RGD on cell growth,cell fusion and expression of exogenous gene. METHODS: A new medium was prepared by adding different concentrations of RGD to ordinary culture medium. The optimum concentration of RGD was determined by observation of the growth of human pancreatic epithelial cell line HPDE6-C7. After determining the optimum concentration of RGD,different concentrations of cells HPDE6-C7 (5×104,105,5×105 mL－1) were inoculated in the two mediums. The morphology,adherence,growth and density of the cells were observed by inverted microscope; The ratio of clone formation and the positive rate of cloning were compared between the two cultures after fusion; The fluorescence intensity after the transfection of plasmid with green fluorescent protein (GFP) and the protein expression after transfection of plasmid with KRAS were observed to campare the expression of exogenous genes between the new medium with ordinary medium. RESULTS: Firstly,the optimal concentration of RGD was 10 ng/mL. Compared with the normal medium,the cultured cells with RGD had better morphology,adhesion and faster proliferation. In addition,both of the number and positive rate of clones formed in the new medium were significantly higher than that in the ordinary medium (P<0.05);The fluorescence intensity after transfection of exogenous gene GFP in the new medium was significantly higher than that in normal medium (P<0.05); Expression level of exogenous gene KRAS of the new medium was also significantly higher than that in normal medium. CONCLUSION: The new culture medium has highlighted advantages in cell growth,cell fusion and expression of exogenous genes. RGD peptide has widely prospect and potential value in the cell culture.

Camellianols A-G, Barrigenol-like Triterpenoids with PTP1B Inhibitory Effects from the Endangered Ornamental Plant Camellia crapnelliana.

Seven new naturally occurring barrigenol-like compounds, camellianols A-G (1-7), and 10 known triterpenoids were isolated from the twigs and leaves of the cultivated endangered ornamental plant Camellia crapnelliana. According to the ECD octant rule for saturated cyclohexanones, the absolute configurations of camellianols D (4) and E (5) were defined. The backbones of the remaining new isolates are assumed to have the same absolute configuration as compounds 4, 5, and harpullone (12). Compounds 2, 3, 9, 10, 13, and 16 exhibited inhibitory effects on the protein tyrosine phosphatase 1B (PTP1B) enzyme, with IC50 values less than 10 µM.

[Vasectomy has no obvious longterm influence on the levels of serum androgens in aging males].

OBJECTIVE: To explore the longterm influence of vasectomy on the levels of serum androgens in aging males. METHODS: Using stratified random sampling, we conducted a questionnaire survey and physical examinations among 437 adult males aged ≥40 years, 232 with and 205 without the history of vasectomy. In addition, we measured the levels of serum total testosterone (TT), sexhormone binding globulin (SHBG), calculated free testosterone (cFT), testosterone secreting index (TSI), free testosterone index (FTI), and luteinizing hormone (LH). RESULTS: Compared with the nonvasectomy group, the vasectomy group showed significantly increased levels of serum TT (ï¼»16.01±5.41ï¼½ vs ï¼»17.39±6.57ï¼½ nmol/L), SHBG (ï¼»58.91±36.89ï¼½ vs ï¼»70.28±40.90ï¼½ nmol/L), and LH (ï¼»8.86±6.49ï¼½ vs ï¼»10.85±11.73ï¼½ IU/L) (all P< 0.05) and a decreased level of FTI (0.33±0.15 vs 0.30±0.12, P< 0.05). There were no statistically significant differences between the nonvasectomy and vasectomy groups in cFT (ï¼»0.24±0.07ï¼½ vs ï¼»0.23±0.09ï¼½ nmol/L) or TSI (ï¼»2.42±1.34ï¼½ vs ï¼»2.46±1.51ï¼½ nmol/IU) (both P>0.05), nor after adjustment for relevant factors in TT (ß: 1.015, 95% CI: －0.180－2.210), SHBG (ß: 5.118, 95% CI: －2.069－12.305), cFT (ß: 0.003, 95% CI: －0.011－0.018), FTI (ß: －0.012, 95% CI: －0.035－0.011), TSI (ß: 0.138, 95% CI: －0.131－0.407), and LH (ß: 1.011, 95% CI: －0.811－2.834) (all P>0.05). CONCLUSIONS: Vasectomy has no obvious longterm influence on the levels of serum androgens in aging males.

Mitochondrial introgression and complex biogeographic history of the genus Picea.

Biogeographic history of plants is much more complex in the Northern Hemisphere than in the Southern Hemisphere due to that both the Bering and the North Atlantic land bridges contributed to floristic exchanges in the Cenozoic, which led to hybridization between congeneric species from different continents. It would be interesting to know how intercontinental gene flow and introgression have affected plant phylogenetic reconstruction and biogeographic inference. In this study, we reinvestigated the phylogenetic and biogeographic history of Picea, a main component of the Northern Hemisphere forest with many species that originated from recent radiation, using two chloroplast (cp), one mitochondrial (mt) and three single-copy nuclear gene markers. The generated gene trees are topologically highly discordant and the geographically closely related species generally show a close affinity of mtDNA rather than cp- or nuclear DNA, suggesting that inter- and intra-continental gene flow and mtDNA introgression might have occurred commonly. However, all gene trees resolved Picea breweriana as the basal-most lineage, which, together with fossil evidence, supports the North American origin hypothesis for the genus. Both dispersal and vicariance have played important roles in the evolution of Picea, and the Bering Land Bridge could have mediated the "North America to Eurasia" dispersal at least two times during the Miocene and Pliocene. Our study again demonstrates the importance of applying data from three genomes for a clear understanding of evolutionary histories in the pine family. Any markers from a single genome alone will not reveal a clear picture of the phylogenetic relationships among closely related congeneric species. In particular, mtDNA markers should be cautiously used, considering that introgression of the maternally inherited mtDNA with a lower rate of gene flow (by seeds) could have occurred much more frequently than that of the paternally inherited cpDNA with a higher rate of gene flow (by pollen) in Pinaceae.