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This paper studies the continuous-time dynamics of VIX with stochastic volatility and jumps in VIX and volatility. Built on the general parametric affine model with stochastic volatility and jumps in the logarithm of VIX, we derive a linear relationship between the stochastic volatility factor and the VVIX index. We detect the existence of a co-jump of VIX and VVIX and put forward a double-jump stochastic volatility model for VIX through its joint property with VVIX. Using the VVIX index as a proxy for stochastic volatility, we use the MCMC method to estimate the dynamics of VIX. Comparing nested models of VIX, we show that the jump in VIX and the volatility factor are statistically significant. The jump intensity is also stochastic. We analyse the impact of the jump factor on VIX dynamics. [ABSTRACT FROM PUBLISHER]

ABSTRACT (+)-Catechin, a potential beneficial compound to human health, is widely distributed in plants and foods. A high-performance liquid chromatography with diode array detector and combined with electrospray ionization ion trap time-of-flight multistage mass spectrometry method was applied to profile and identify the metabolites of (+)-catechin in rats and to study the distribution of these metabolites in rat organs for the first time. In total, 51 phase II metabolites (44 new) and three phase I metabolites were tentatively identified, comprising 16 (+)-catechin conjugates, 14 diarylpropan-2-ol metabolites, 6 phenyl valerolactone metabolites and 18 aromatic acid metabolites. Further, 19 phase II metabolites were new compounds. The in vivo metabolic reactions of (+)-catechin in rats were found to be ring-cleavage, sulfation, glucuronidation, methylation, dehydroxylation and dehydrogenation. The numbers of detected metabolites in urine, plasma, small intestine, kidney, liver, lung, heart, brain and spleen were 53, 23, 27, 9, 7, 5, 3, 2 and 1, respectively. This indicated that small intestine, kidney and liver were the major organs for the distribution of (+)-catechin metabolites. In addition, eight metabolites were found to possess bioactivities according to literature. These results are very helpful for better comprehension of the in vivo metabolism of (+)-catechin and its pharmacological actions, and also can give strong indications on the effective forms of (+)-catechin in vivo. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Based on the slab continuous casting under hydraulic oscillation, the measurement method of mould friction -- friction work measurement method is studied. The extraction and the realization of friction work measurement method are discussed and the error of friction is also analyzed and verified through the casting tests. Finally, according to the monitored data in slab continuous casting, the effects of casting speed on friction are discussed, and the comparative analysis is carried out to the friction results under the sinusoidal mode and the non-sinusoidal mode. The results show that the friction monitored by the friction work method can well reflect the lubrication situation between the mould and slab. This research provides the theoretical and experimental bases for the mould friction monitored online with the friction work method under the hydraulic oscillation. [ABSTRACT FROM AUTHOR]

Highlights: [•] A novel strategy to find absorbed constituents and metabolites of TCMs was proposed. [•] Absorption and metabolism of Paeoniae Radix Rubra were studied for the first time. [•] 13 new absorbed constituents of Paeoniae Radix Rubra were reported for the first time. [•] 90 new metabolites of PRR decoction were tentatively identified by LC–MS technique. [•] 22 new metabolites of paeoniflorin were reported for the first time. [Copyright &y& Elsevier]

This study aimed to prepare Gardenia fructus carbon dots (GF-CDs) and examine their efficacy in mitigating oxidative stress and apoptosis in intestinal porcine epithelial cells from the jejunum (IPEC-J2 cells) induced by lipopolysaccharide (LPS). The GF-CDs were synthesized using a one-step hydrothermal method. The oxidative damage model of IPEC-J2 cells was induced through LPS treatment. The potential mechanism by which GF-CDs affect cellular oxidative damage was examined through the perspectives of apoptosis, reactive oxygen species level, antioxidant-related enzyme index, mRNA transcription of antioxidant-related genes, and the expression of antioxidant proteins. The results revealed that GF-CDs, characterized by particle sizes<7 nm, abundant functional groups, and good water solubility, were synthesized using a one-step hydrothermal method. The carbon spots of Gardenia fructus at concentrations of 50, 100, and 200 μg/mL exhibited protective effects, as evidenced by their ability to enhance viability ( P <0.01) and restore cellular morphology after oxidative damage. The GF-CDs decreased oxidative damage and reduced the apoptosis rate of cells by upregulating AKT1 expression and downregulating the expression of Caspase 3, STAT3, TNF-α, and JNK. These results indicate that GF-CDs have the characteristic physicochemical properties of CDs, exhibit biological activities related to antioxidation and cellular damage mitigation, and may serve as a potential healthcare product in swine raising., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Chen, Zang, Mo, Zhang, Wang, Wang and Li.)

Dihydroxy acid dehydratase (DHAD) is the third enzyme in the plant branched-chain amino acid biosynthetic pathway and the target for commercial herbicide development. We have previously reported the discovery of fungal natural product aspterric acid (AA) as a submicromolar inhibitor of DHAD through self-resistance gene directed genome mining. Here, we reveal the mechanism of AA inhibition on DHAD and the self-resistance mechanism of AstD, which is encoded by the self-resistance gene ast D. As a competitive inhibitor, the hydroxycarboxylic acid group of AA mimics the binding of the natural substrate of DHAD, while the hydrophobic moiety of AA occupies the substrate entrance cavity. Compared to DHAD, AstD has a relatively narrow substrate channel to prevent AA from binding. Several mutants of DHAD were generated and assayed to validate the self-resistance mechanism and to confer Arabidopsis thaliana DHAD with AA resistance. These results will lead to the engineering of new type of herbicides targeting DHAD and provide direction for the ecological construction of herbicide-resistant crops., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2024 Xin Zang et al.)

Vaccines represent a significant milestone in the history of human medical science and serve as the primary means for controlling infectious diseases. In recent years, the geographical distribution of Japanese encephalitis viruses (JEV) of various genotypes has become increasingly complex, which provides a rationale for the development of safer and more effective vaccines. The advent of subunit and nucleic acid vaccines, especially propelled by advancements in genetic engineering since the 1980s, has accelerated the application of novel adjuvants. These novel vaccine adjuvants have diversified into toll-like receptor (TLR) agonists, complex adjuvants, nanoparticles and so on. However, the efficacy of adjuvant combinations can vary depending on the host system, disease model, or vaccine formulation, sometimes resulting in competitive or counteractive effects. In our previous study, we constructed a pJME-LC3 chimeric DNA vaccine aimed at inducing an immune response through autophagy induction. Building on this, we investigated the impact of the TLR7/8 agonist imiquimod (IMQ) and the TLR9 agonist CpG ODN 1826 as adjuvants on the immunogenicity of the Japanese encephalitis chimeric DNA vaccine. Our findings indicate that the combination of the pJME-LC3 vaccine with IMQ and CpG ODN 1826 adjuvants enhanced the innate immune response, promoting the maturation and activation of antigen-presenting cells in the early immune response. Furthermore, it played a regulatory and optimizing role in subsequent antigen-specific immune responses, resulting in effective cellular and humoral immunity and providing prolonged immune protection. The synergistic effect of IMQ and CpG ODN 1826 as adjuvants offers a novel approach for the development of Japanese encephalitis nucleic acid vaccines., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Background: The clinical response rate to immune checkpoint blockade (ICB) therapy in melanoma remains low, despite its widespread use. Circular non-coding RNAs (circRNAs) are known to play a crucial role in cancer progression and may be a key factor limiting the effectiveness of ICB treatment., Methods: The circRNAs that were downregulated after coadministration compared with single administration of PD-1 inhibitor administration were identified through RNA-seq and Ribo-seq, and thus the circPIAS1 (mmu&#95;circ&#95;0015773 in mouse, has&#95;circ&#95;0008378 in human) with high protein coding potential was revealed. Fluorescence in situ hybridization (FISH) assays were conducted to determine the localization of circPIAS1 in human and mouse melanoma cells, as well as its presence in tumor and adjacent tissues of patients. Validation through dual-luciferase reporter assay and LC-MS/MS confirmed the ability of circPIAS1 to encode a novel 108 amino acid polypeptide (circPIAS1-108aa). Specific antisense oligonucleotides (ASOs) targeting the junction site of circPIAS1 were developed to reduce its intracellular levels. Proliferation changes in melanoma cells were assessed using CCK8, EdU, and colony formation assays. The impact of circPIAS1-108aa on the ferroptosis process of melanoma cells was studied through GSH, MDA, and C11-BODIPY staining assays. Western Blot, Immunoprecipitation (IP), and Immunoprecipitation-Mass Spectrometry (IP-MS) techniques were employed to investigate the impact of circPIAS1-108aa on the P-STAT1/SLC7A11/GPX4 signaling pathway, as well as its influence on the balance between STAT1 SUMOylation and phosphorylation. Additionally, a melanoma subcutaneous transplanted tumor mouse model was utilized to examine the combined effect of reducing circPIAS1 levels alongside PD-1 inhibitor., Results: Compared with the group treated with PD-1 inhibitor alone, circPIAS1 was significantly down-regulated in the coadministration group and demonstrated higher protein coding potential. CircPIAS1, primarily localized in the nucleus, was notably upregulated in tumor tissues compared to adjacent tissues, where it plays a crucial role in promoting cancer cell proliferation. This circRNA can encode a unique polypeptide consisting of 108 amino acids, through which it exerts its cancer-promoting function and impedes the effectiveness of ICB therapy. Mechanistically, circPIAS1-108aa hinders STAT1 phosphorylation by recruiting SUMO E3 ligase Ranbp2 to enhance STAT1 SUMOylation, thereby reactivating the transduction of the SLC7A11/GPX4 signaling pathway and restricting the immunogenic ferroptosis induced by IFNγ. Furthermore, the combination of ASO-circPIAS1 with PD-1 inhibitor effectively inhibits melanoma growth and significantly enhances the efficacy of immune drugs in vivo., Conclusions: Our study uncovers a novel mechanism regarding immune evasion in melanoma driven by a unique 108aa peptide encoded by circPIAS1 in melanoma that dramatically hinders immunogenic ferroptosis triggered by ICB therapy via modulating the balance between SUMOylation and phosphorylation of STAT1. This work reveals circPIAS1-108aa as a critical factor limiting the immunotherapeutic effects in melanoma and propose a promising strategy for improving ICB treatment outcomes., (© 2024. The Author(s).)

Human diseases often correlate with changes in protein glycosylation, which can be observed in serum or plasma samples. N-glycosylation, the most common form, can provide potential biomarkers for disease prognosis and diagnosis. However, glycoproteins constitute a relatively small proportion of the total proteins in human serum and plasma compared to the non-glycosylated protein albumin, which constitutes the majority. The detection of microheterogeneity and low glycan abundance presents a challenge. Mass spectrometry facilitates glycoproteomics research, yet it faces challenges due to interference from abundant plasma proteins. Therefore, methods have emerged to enrich N-glycans and N-linked glycopeptides using glycan affinity, chemical properties, stationary phase chemical coupling, bioorthogonal techniques, and other alternatives. This review focuses on N-glycans and N-glycopeptides enrichment in human serum or plasma, emphasizing methods and applications. Although not exhaustive, it aims to elucidate principles and showcase the utility and limitations of glycoproteome characterization., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objectives: To compare the safety and efficacy of del-Nido cardioplegia (DNC) with traditional 4:1 cold blood cardioplegia (CBC) in coronary artery bypass grafting and/or valve surgeries in elderly patients., Methods: The present study is a retrospective case-series study that included 302 consecutive patients aged 70 years and over who underwent on-pump valve surgery and/or coronary artery bypass graft (CABG). DNC was administered to 90 patients and CBC to 212 patients. After propensity-score matching, 89 pairs were compared. The safety and efficacy were analyzed between the two groups., Results: The DNC group had a similar mortality (3.4% vs. 5.6%, OR = 0.79, P = 0.720) and extracorporeal membrane oxygenation (ECMO) implantation rate (1.1% vs. 2.2%, OR = 0.75, P = 1.000) to the CBC group, a lower incidence of postoperative intra-aortic balloon pump (IABP) implantation (1.1% vs. 9.0%, OR = 0.54, P = 0.034) and a higher left ventricular ejection fraction (LVEF) at discharge (60 (56-64) % vs. 57 (51-62)%, P = 0.007). The estimated glomerular filtration rate (eGFR) in the DNC group was higher when the patient was transferred to the intensive care unit (79.4 (65.0-94.3) ml/min/1.73m 2 vs. 77.2 (59.8-88.7) ml/min/1.73m 2 , P = 0.014), but no significant differences were identified after 24 h. The serum lactate values of the DNC group were significantly lower than those of the CBC group (0 h: 2.7 (2.0-3.2) vs. 3.2 (2.4-4.4), P = 0.001; 3 h: 3.2 (2.0-4.8) vs. 4.8 (2.8-6.6), P < 0.001; 6 h: 3.5 (2.2-5.4) vs. 5.8 (3.4-8.4), P < 0.001; 9 h: 3.4 (2.0-7.0) vs. 5.5 (2.9-8.3), P = 0.005). There were no differences between the two groups in respect of lactate levels at 12 h and thereafter. Postoperative creatinine kinase-MB concentrations were similar between the two groups., Conclusions: Del-Nido cardioplegia is safe and effective in elderly patients undergoing CABG and/or valve surgery., (© 2023. The Author(s).)

Overcoming resistance to bioactive small molecules is a significant challenge for health care and agriculture. As a result, efforts to uncover the mechanisms of resistance are essential to the development of new antibiotics, anticancer drugs and pesticides. To study how nature evolves resistance to highly potent natural products, we examined the biosynthesis and mechanism of self-resistance of the fungal glyceraldehyde-3-phosphate dehydrogenase (GAPDH) inhibitor heptelidic acid (HA). HA is a nanomolar inhibitor of GADPH through the covalent modification of the active site cysteine thiol. The biosynthetic pathway of HA was elucidated, which uncovered the enzymatic basis of formation of the epoxide warhead. Structure-activity relationship study using biosynthetic intermediates established the importance of the fused lactone ring system in HA. The molecular basis of HA inhibiting human GAPDH was illustrated through the crystal structure of Hs -GAPDH covalently bound with HA. A GAPDH isozyme HepG encoded in the HA cluster was characterized to be less sensitive to HA, and therefore contribute to self-resistance for the producing host. Comparison of the crystal structures of human GAPDH and HepG showed mutations both within and remote to the active site can contribute to resistance of inactivation, which was confirmed through mutagenesis. Due to the critical role GAPDH plays in aerobic glycolysis and other cellular functions, knowledge of HA mode of action and self-resistance mechanism could accelerate the development of improved inhibitors., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

This study is to establish the characteristic HPLC chromatogram of phenols in Ephedrae Herba, from which to pick out the marker peaks, followed by the analysis of the regularity of their distribution and content in the herbaceous stems of Ephedra sinica, E. intermedia and E. equisetina. The HPLC-DAD method for the characteristic chromatogram as well as quantitative analysis was established. The separation was carried out on a YMC-Pack ODS-A column (4.6 mm x 250 mm, 5 µm), eluted with the mobile phases as 0.01% formic acid aqueous solution (A) and acetonitrile (B) in a linear gradient (0-10 min, 17% B; 10-25 min, 17%-19% B; 25- 33 min, 19%-48% B; 33-35 min, 48%-51% B; 35-44 min, 51% B). The flow rate was kept at 1.0 mL · min⁻¹. The column tem- perature was 40 °C, and the detection wavelength was set at 350 nm (0-16 min) and 330 nm (16-44 min). Forty-six batches of collected samples from three official origins of Ephedrae Herba were detected, whose liquid chromatograms proven to be helpful to the differentiation of different origins. With principal component analysis and the analysis of distribution of peak area, twelve key peaks from the chromatogram were discussed in details on their contributions to the characteristics and differences of three official origins of the herb: peak area of peak 10, 11, 12 were found out to be significantly higher in E. equisetina than in other two origins, whose sum (higher than 146 mAU in E. equisetina) was useful for the discrimination between E. equisetina and the other two origins; peak area of 1 and 4 were respectively higher in E. sinica and E. intermedia than in other official origins, indicating their important effect on the differen- tiation of corresponding origins; peak 8 and 9 were picked out as two characteristic common peaks in three official origins of the herb, whose peak area showed little difference among different origins; further, peak area of other key peaks in the chromatogram also showed some difference among three origins, which make contributions to the differentiation of origins as well. Then, four phenols as 2"-O-α- L-rhamnosyl-isovitexin (1), vitexin (2), pollenitin B (5) and herbacetin-7-O-β-D-glucoside (6) were quantitative analyzed with the above-mentioned method, with good linear relationship and accuracy (recoveries in a range of 97.8%-102.5%). The content of the four phenols were firstly reported in Ephedrae Herba from official origins, which were respectively trace-1.55 (1), trace-0.160 (2), trace-0.284 (5) and trace-0.620 (6) mg · g⁻¹ in all of the tested samples. In addition, the content of these phenols showed differences in three official origins, especially 1, whose content in E. sinica [(0.670 ± 0.88) mg ± g⁻¹] were significantly higher than in other two origins (lower than 0.16 mg ± g⁻¹ besides sample Ei-060630-2-2), and 6, whose average content in E. equisetina [(0.260 ± 0.039 2) mg · g⁻¹] were twice as high as in E. sinica [(0.120 ± 0.270) mg · g⁻¹] and E. intermedia [(0.136 ± 0.485) mg g⁻¹], indicating the important effects of the two constituents on the differentiation among three official origins of the herb. The method established for the characteristic HPLC chromatogram and quantitative analysis of phenols was simple and accurate, and the marker constituents selected may provide new guides for the discrimination of official origins as well as the improvement of quality criteria of EphedraeHerba.

(+)-Catechin, a potential beneficial compound to human health, is widely distributed in plants and foods. A high-performance liquid chromatography with diode array detector and combined with electrospray ionization ion trap time-of-flight multistage mass spectrometry method was applied to profile and identify the metabolites of (+)-catechin in rats and to study the distribution of these metabolites in rat organs for the first time. In total, 51 phase II metabolites (44 new) and three phase I metabolites were tentatively identified, comprising 16 (+)-catechin conjugates, 14 diarylpropan-2-ol metabolites, 6 phenyl valerolactone metabolites and 18 aromatic acid metabolites. Further, 19 phase II metabolites were new compounds. The in vivo metabolic reactions of (+)-catechin in rats were found to be ring-cleavage, sulfation, glucuronidation, methylation, dehydroxylation and dehydrogenation. The numbers of detected metabolites in urine, plasma, small intestine, kidney, liver, lung, heart, brain and spleen were 53, 23, 27, 9, 7, 5, 3, 2 and 1, respectively. This indicated that small intestine, kidney and liver were the major organs for the distribution of (+)-catechin metabolites. In addition, eight metabolites were found to possess bioactivities according to literature. These results are very helpful for better comprehension of the in vivo metabolism of (+)-catechin and its pharmacological actions, and also can give strong indications on the effective forms of (+)-catechin in vivo., (Copyright © 2013 John Wiley & Sons, Ltd.)

Aim: To determine the proliferative potential and the maintenance of stem cell activity in stored human limbal tissues, and correlate this with the preservation time, cell viability and the expression of stem cell markers., Methods: Thirty limbal rims were split into 4 parts and stored in corneal preservation medium at 4°C for 0, 1, 4, or 7 days. The limbal stem cell and mitotic markers P63, CK19, proliferating cell nuclear antigen (PCNA), and Ki67 were determined by immunohistochemical staining. The proliferative potential of limbal epithelial cells was assessed by cell viability, the ability of generating stratified epithelium, and colony forming assay., Results: The stored tissues maintained limbal stratified structure to 7 days and exhibited comparable expression level of stem cell and mitotic markers. The proportion of viable cells decreased with the prolonged preservation time, while colony forming efficiency decreased from the 1(st) day and disappeared at the 4(th) day. When inoculated on amniotic membrane, the cells preserved for 1 day formed a stratified epithelium, while the cells from 4 days' preservation formed a discontinuous layer., Conclusion: The colony forming efficiency of limbal epithelial stem/progenitor cells decreased rapidly with the increasing preservation time, while the expression level of markers and capacity of forming epithelial monolayer on amniotic membrane decreased gradually. The limbal epithelial stem cells lost their function earlier than the lost expression level of stem cell markers. This may help us to better choose the appropriate preservation grafts for future limbal stem cell transplantation.

Aim: To investigate the infiltration and activation of lymphocyte in iris-ciliary body and anterior chamber after allogenic penetrating keratoplasty (PK), for further revealing the role of iris-ciliary body in corneal allograft immune rejection., Methods: In the mice models of PK, BALB/C mice received orthotopic isografts (n =35) or C57BL/6 donor allografts (n =25). Grafts were examined daily for 3 weeks by slit-lamp microscopy and scored for opacity. The infiltration of CD4(+) T lymphocyte in iris-ciliary body and anterior chamber was examined by immunohistology and the mRNA of CD80 and CD86 in both cornea graft and iris-ciliary body by RT-PCR was analyzed in allograft recipient at days 3, 6, 10 and the day when graft rejection occurred. Isograft recipients were examined as control at the corresponding time points. Transmission electron microscope was used to study the ultrastructure, especially cell infiltration, of iris-cilary body and corneal graft at day 3, 7 and the day when rejection occurred after allogenic PK., Results: Rejection was observed in all the allograft recipients followed more than 10 days, at a median time of 15 days (range 12-18 days), but not in any of isografts. CD4(+) T cells were first detected at day 6 after transplantation in limbus and Ciliary body, and then in the stroma of recipient, iris, anterior chamber and corneal allograft with an increased number until graft rejection occurred. CD80 and CD86 mRNA were detected under RT-PCR examination in both graft and iris-ciliary body of allograft recipient, but not in any of isograft recipient. Three days after operation, lymphocytes and monocytes macrophages were visible in iris blood vessels and the anterior chamber, and vascular endothelial cell proliferation and activation were significant under transmission electron microscopy examination. At day 7, corneal endothelial cells became thinner. Lymphocytes and mononuclear macrophages were found with great number in the anterior chamber and adhered to the corneal endothelium. Blood vessels in iris increased and were filled with lymphocytes. And lymphocytes were detected to migrate through endothelial cell gap out of vessels. When allograft rejection occurred, macrophages attached to endothelial cells with large number of lymphocytes and macrophages infiltrating in iris., Conclusion: Lymphocyte infiltration and activation occurred in iris-ciliary body after allogenic PK, and the lymphocytes could migrate from iris blood vessel to the anterior chamber, which might play an important role in corneal allograft immune rejection.

Objective: To study telomere length, senescence-associated-beta-galactosidase (SA-beta-galactosidase) and senescence marker protein-30 (SMP-30) in the stromal cells of keratoconus or normal corneas respectively, aiming finding the association of these indexes with the phenotype of keratoconus., Methods: Experiment research. 37 keratoconus lesions corneas were removed from 32 keratoconus patients who were operated in Shangdong Eye Institute between January 2006 and December 2006, and 20 normal corneas were collected from eye bank. The keratoconus corneas ages were from 13 to 34 years [mean ages (19 + or - 5) years] and the control group consists of 20 normal corneas donor ages from 9 to 30 years [mean ages (19 + or - 4) years]. And there was no statistical difference of ages between keratoconus and normal corneas. Southern blot method was utilized to detect telomere length of genomic DNA. SA-beta-galactosidase was detected by 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-Gal) staining method respectively in keratoconus and normal corneas. Isolated mRNA from keratoconus and normal corneas were reverse-transcribed to cDNA and SMP-30 was detected using PCR with specific primers (sense: 5' ccg tgg atg cct ttg act at 3'; anti-sense: 5' caa ctt cat gc tgct ttg ga 3'). To compare normal corneas and keratoconus corneas by histopathological study. Statistical analysis by t test., Results: The telomere length in stromal cells in keratoconus corneas were from 10.29 to 14.12 kb, mean (11.54 + or - 1.41) kb, while that of normal corneas were from 12.64 to 15.32 kb, mean (13.45 + or - 0.99) kb. The difference of telomere length in stromal cells of keratoconus and normal corneas reached a statistical significant level (t = 4.753, P < 0.05). That means the telomere length of keratoconus stroma was shorter than that of normal corneal stroma. Light microscopy revealed that collagen fibers in keratoconus corneal stroma were arranged in an irregular manner. Cells density in keratoconus stroma appeared lower than in normal ones but the decrease was not significant. The staining of SA-beta-galactosidase in the keratoconus section was evident, but there was no staining in the normal corneas. SMP-30 was not detectable with RT-PCR method in either keratoconus or normal corneas., Conclusion: Telomeres in the keratoconus stromas manifest higher SA-beta-galactosidase than control, implying that improper senescence might be involved in pathogenesis of keratoconus.

Objective: To study the chemical constituents from the ethyl acetate portion of an ethanolic extractive of the leaves of Aeschynanthus mengxinensis., Method: The column chromatographic techniques were applied to isolate constituents. A combination of IR, ESI-MS, NMR and 2D-NMR spectroscopy was used to identify structures., Result: Four compounds were isolated from the ethyl acetate fraction of this plant, and the structure of them have identified as 2alpha, 3beta, 19beta-trihydroxyolean-12-ene-23,28-dioic acid (1), 2alpha, 3beta, 21beta-trihydroxyolean-12-ene-28-oic acid (2), 2alpha, 3beta, 23-trihydroxyurs-12-ene-28-oic acid (3) and stigmast-5 (6), 22 (23)-diene-3beta-ol (4)., Conclusion: The NMR data of compound 1 was completely assigned by 2D-NMR techniques, including HMBC and HMQC. Compounds 1-4 were isolated for the first time from Gesneriaceae.

To separate and identify the chemical constituents from the leaves of Broussonetia papyrifera (Linn.) Vent, various columns including Diaion HP-20, Toyopearl HW-40C, Sephadex LH-20, silica gel were employed for the isolation and purification of compounds from the leaves of B. papyrifera. The structures of the compounds were elucidated by their physiochemical characteristics and spectral data. Nineteen compounds were isolated from the leaves of B. papyrifera and their structures were identified as apigenin (1), apigenin-7-O-beta-D-glucopyranoside (2), chrysoerid-7-O-beta-D-glucopyranoside (3), apigenin-7-O-beta-D-glucopyranuronide (4), vitexin-7-O-beta-D-glucopyranoside (5), luteolin (6), 5,7,4'-trihydroxyl-6-C-[a-L-rhamnopyranosyl (1-->2)]-beta-D-glucopyranosyl flavone (7), 5,7,4'-trihydroxyl-8-C-[a-L-rhamnopyranosyl (1-->2)]-beta-D-glucopyranosyl flavone (8), saponaretin (9), vitexin (10), benzyl benzoate-2, 6-di-O-beta-D-glucopyranoside (11), (2R, 3R, 5R, 6S, 9R)-3-hydroxy-5,6-epoxy-beta-ionol-2-O-beta-D-glucopyranoside (12), (2R, 3R, 5R, 6S, 9R)-3-hydroxyl-5,6-epoxy-acetyl-beta-ionol-2-O-beta-D-glucopyranoside (13), ficustriol (14), (6S, 9S)-roseoside (15), 3beta-hydroxy-5alpha,6alpha-epoxy-beta-ionone-2alpha-O-beta-D-glucopyranoside (16), icariside B1 (17), sammangaoside A (18), 3-hydroxy-5alpha,6alpha-epoxy-beta-ionone (19). Compounds 11, 12 and 13 are new compounds, the others are isolated from this genus Broussonetia for the first time.

Objective: To evaluate the effect of liposome mediated plasmids encoding endostatin (ES) injected into the vitreous to inhibit experimental retinal neovascularization., Methods: Cationic liposome mediated ES expression plasmid PCDNA(3)-ES was constructed. One-week-old C57Bl/6N mice were exposed to (75 +/- 2)% oxygen for 5 days, then returned to the room air to induce retinal neovascularization. Cationic liposome mediated ES complex (2 microl) was injected into the vitreous in the treatment group. PBS 2 microl or liposome with carrier DNA complex were injected in the control group. The ES protein expression in the retina was tested with immunohistological methods at 1, 3, 7 and 14 days after injection. Retinal neovascularization was evaluated by angiography with injection of fluorescein dextran and quantification of neovascular proliferative retinopathy after 5 days in room air. To examine the toxicity of the liposome and plasmid PCDNA(3)-ES complex, the histological changes in the retina were examined by light and electron microscopy., Results: ES protein was expressed in the retina 24 hours after injection. Most of them presented in the retinal ganglion layer. This could last for 2 weeks at least. Retina of the PBS-injected eyes of retinal neovascular animal model showed prominent neovascular tuft and fluorescein leakage. Fewer neovascular tufts could be seen after ES injection. Retinal neovascularization in the eyes injected with ES plasmids complex was reduced as compared with the control group. No side effect on the retina was observed by light and electron microscopy., Conclusions: Liposome mediated plasmids encoding ES can be transferred to retinal cells by vitreous injection and can suppress retinal neovascularization, no side or toxic effects are presented in the retina. Further studies should be done to improve the treatment results.

Objective: To evaluate the changes of porcine corneal endothelium, the morphology, histology, ultrastructure, enzymes activity and metabolism of the cornea induced by organ culture with two different media containing fetal bovine serum (FBS) or human umbilical cord serum (HCS)., Methods: Fifty pairs of porcine corneas were preserved at 31 degrees C for 7, 14, 21, 28 days. One cornea of each pair was cultivated in medium I containing 10% FBS (group 1); the other one was stored in medium II containing 10% HCS (group 2). Thirteen fresh porcine corneas served as controls. All stored corneas were dehydrated for 24 hours. Twelve corneas from each group were evaluated each week, including the morphology, histology and enzyme histochemical staining of the cornea. Scanning electron microscopy was performed on one cornea from each group at 14 and 28 days and compared with the fresh cornea. pH value, glucose and lactate concentration of the culture media before and after culture were examined. Microbiological evaluation was also performed., Results: Endothelium evaluation did not differ statistically between the two groups of porcine corneas. The morphological endothelium study showed some alterations such as pleomorphism. After 28 days of cultivation, the mean cell losses of endothelium were 10.98% and 10.85% in medium I and medium II stored corneas, respectively. There were no statistical differences of the histology, ultrastructure and enzymes activity of corneas between the two groups. The histological study showed corneal swelling and epithelial sloughing after preservation. Scanning electron microscopy showed an intact endothelial layer in all corneas. Enzyme histochemical staining showed vigorous enzyme activity in the corneal epithelium and endothelium. Enzyme activity in stroma decreased with preservation time. Corneas showed good glucose metabolism. Incidence of contamination was 6% for storage medium., Conclusions: The corneal endothelium can maintain a good viability for 4 weeks in these two organ culture media. HCS can replace FBS in the organ culture medium.