[Short-term outcomes of all-inside endoscopic running locked stitch technique for acute achilles tendon ruptures]

Objective: To evaluate the short-term outcomes of all-inside endoscopic running locked stitch technique for acute Achilles tendon ruptures. Methods: This is a retrospective case series study. Forty cases with acute Achilles tendon rupture were treated with the all-inside endoscopic running locked stitch technique from April 2020 to March 2022. There were 44 males and 4 females, aged (34.8±7.4) years (range: 24 to 50 years). Body mass index was (21.2±2.4)kg/m2 (range: 18 to 26 kg/m2); There were 29 cases (60.4%) on the left side and 19 cases (39.6%) on the right side. Under endoscopic control, the proximal tendon stumps were stitched with the running locked method using a semi-automatic flexible suture passer. The threads of the high-strength suture were grasped through the paratenon sub-space and then fixed into calcaneal insertion with a knotless anchor. MRI of Achilles tendon, surgical time and complications were assessed. Achilles tendon total rupture score (ATRS), Achilles tendon resting angle, and heel rise height scale were utilized to evaluate final clinical outcomes. The differences of bilateral limbs were compared using the paired t test. Results: The follow-up time was (24.1±3.5)months (range:18 to 32 months). Appropriate tendon regeneration was observed on MRI at post-operative 12 months. The median ATRS score (M(IQR)) was 95.0 (4.7) points. Furthermore, there was no significant difference between the injured and contralateral side in the Achilles tendon resting angle ((17.1±2.4)° vs. (17.4±2.6)°, t=1.92,P=0.062) and heel rise height ((14.2±1.7)cm vs. (14.4±1.5)cm, t=1.71,P=0.094). No nerve injuries, infection, deep vein thrombosis and re-ruptures were encountered. Sports activity resumed six months postoperative in 46 patients. One patient had a slight anchor cut-out, due to an addition injury, which was removed after 5 months. Conclusions: All-inside endoscopic running locked stitch technique for acute Achilles tendon ruptures shows promising results. It provides stable connection of the tendon stumps with a low risk of complications.

[Research progress on the role of glucose in regulating immune homeostasis]

Glucose is the central nutrient for energy metabolism and life support in the human body. As the main energy substance of the body, glucose is essential for the normal function of immune cells and their proliferation; when glucose homeostasis is disrupted in the body, it may lead to impaired immune system function and pathological conditions. Exploring the relationship between glucose metabolism and immune regulation can help establish the gene regulatory network and figure out potential pathogenic mechanisms under physiological and pathological conditions. This article reviews the current scientific research progress on glucose metabolism and immunity, mainly focusing on the physiological regulatory functions of glucose in maintaining the homeostasis of innate and acquired immunity; and summarizes the research progress on the effects and mechanisms of glucose on tumor immunity and its related therapies under pathological conditions, taking tumors as an example.

Does Dual Anti-HER2 Therapy Increase Early Cardiac Toxicity in Comparison with Trastuzumab Alone in Breast Cancer Patients Receiving Adjuvant Radiotherapy? A Multicenter Retrospective Study

PURPOSE/OBJECTIVE(S)

Adjuvant trastuzumab in combination with RT has proved its safety in terms of cardiac events. Dual anti-HER2 therapy with pertuzumab is currently standard adjuvant therapy in N+ and high-risk N0 early breast cancer (BC) patients. Our study aims to find if it increases early cardiac toxicity compared with trastuzumab alone in BC patients receiving adjuvant radiotherapy.

MATERIALS/METHODS

Operable BC patients who received adjuvant radiotherapy (RT) and trastuzumab with or without pertuzumab between January 2017 and September 2020 in 7 Chinese centers were retrospectively reviewed. The cardiac examination included ultrasonography, electrocardiogram (ECG), NT-proBNP, and cTnI before RT and during follow-up. The cardiac event was any new-onset symptomatic heart disease or abnormality in the cardiac examination after RT.

RESULTS

In total, 711 patients with a median age of 52 years were included, of whom 567 (79.7%) patients were treated with trastuzumab-only and 144 (20.3%) patients received dual anti-HER2 therapy. Adjuvant RT was given concurrently in 140/144 (97.2%) of dual anti-HER2 therapy and 562/567 (99.1%) of trastuzumab alone, respectively. With a median follow-up of 11 months, no patients developed symptomatic heart diseases. Among patients with normal baseline, 17 (2.4%), 86 (12.1%), 18 (2.5%) and 14 (7.3%) developed new-onset diastolic dysfunction, left ventricular ejection fraction (LVEF) decline, abnormal ECG, and abnormal NT-proBNP, respectively. No significant difference was found between the trastuzumab-only and dual anti-HER2 cohort in the incidence of all kinds of new-onset cardiac events (all p > 0.1). Multivariate analysis showed that left-sided (vs right-sided) RT significantly increased the risk of ECG abnormality (HR = 2.32, 95% CI 1.62-3.32, p<0.001). Increased age was an independent risk factor for diastolic dysfunction (HR = 1.1, 95% CI 1.02-1.18, p = 0.0098). Dosimetric analysis showed that patients who developed any cardiac events had increased mean heart dose (397.67±251.08 vs 344.87±236.75 cGy, p = 0.032). A significant increase in risk of cardiac events was found in patients with mean heart dose > 450 cGy (HR = 1.55, 95% CI 1.17-2.05, p = 0.0024), V5 > 26% (HR = 1.51, 95% CI 1.09-2.09, p = 0.013), and V30 > 5.5% (HR = 1.49, 95% CI 1.09-2.04, p = 0.0117), respectively. Further analysis was done in the subgroup of patients treated with left-sided RT, internal mammary nodes RT, or anthracyclines, no difference in risk of cardiac events was found between trastuzumab alone and dual anti-HER2 therapy in concurrent with RT (all p > 0.05).

CONCLUSION

Compared with trastuzumab-only, dual anti-HER2 therapy does not increase early cardiac toxicity in combination with adjuvant RT in BC patients. Cardiac radiation exposure remains the primary risk factor associated with early cardiac toxicity.

[Effect and mechanism of glucocorticoids in preventing stenosis after esophageal endoscopic submucosal dissection]

Objective: To explore the role and specific mechanism of glucocorticoids in preventing stenosis after esophageal endoscopic submucosal dissection (ESD). Methods: Data of 81 patients [51 cases were male and 30 cases were female, aged (62.09±7.95) years] undergoing early esophageal cancer or precancerous lesions with a stripping range ≥3/4 circle hospitalized from January 2019 to February 2021 in Department of Gastroenterology, Zhongda Hospital, Southeast University. They were randomly divided into the control group (n=23), oral prednisone acetate group (n=28) and/or combined with local injection Triamcinolone acetonide group (n=30). Analysis the stenosis rates, endoscopic stent dilatation times, the scores of the Atkinson classification and QLQ-OES18 after 12 weeks. Also the expression of carbohydrate sulfotransferase15 (CHST15) mRNA, TGF-β1 and Collagen-Ⅰ protein were compared by real-time PCR or immunohistochemistry. Results: The stenosis rates of the control group, oral prednisone acetate group and/or combined with local injection Triamcinolone acetonide group were 82.6% (19/23), 46.4% (13/28) and 20.0% (6/30) (P<0.001); endoscopic stent dilatation times [M (Q₁,Q₃)] in these three groups were 2 (1, 3), 0 (0, 0) and 0 (0, 0) (P<0.001). After ESD, the scores of the Atkinson classification and QLQ-OES18 in the three groups were lower than before (P<0.001); and the expression of CHST15 mRNA in the three groups were 4.31±0.13, 3.44±0.07 and 2.84±0.21 respectively (P<0.001). Compared with the control group, the expression of CHST15 mRNA in oral prednisone acetate group was down-regulated (P<0.001), and was the lowest in oral prednisone acetate combined with local injection Triamcinolone acetonide group (P<0.001). As CHST15 mRNA was down-regulated, the expression of TGF-β1 and Collagen-I protein was also down-regulated (P<0.05). Conclusions: Oral prednisone alone or combined with local injection of triamcinolone acetonide both can prevent esophageal stenosis effectively. Oral combined with local injection of glucocorticoid is particularly more effective. Glucocorticoid can reduce the expression of CHST15 mRNA, thereby inhibiting the expression of TGF-β1 and Collagen-I protein.

[Role of lymphocytes in the pathogenesis of autoimmune hepatitis]

In recent years, the number of autoimmune hepatitis cases in the world has shown a significant upward trend, but its etiology and pathogenesis is still unclear. At present, it is generally considered to be caused by abnormal immune regulation mechanism of the body, especially the lymphocytes and their cytokines, which has attracted widespread concern and thus is reviewed here.

Effects of Stephania hainanensis alkaloids on MSU-induced acute gouty arthritis in mice

BACKGROUND

Gout is initiated by the precipitation of monosodium urate (MSU) crystals within the joints and soft tissues, and it can eventually cause acute or chronic arthritis. MSU crystals trigger, amplify, and maintain a strong inflammatory response through promoting proinflammatory activity. In this study, the therapeutic effects of Stephania hainanensis (S. hainanensis) total alkaloid (SHA) were tested and evaluated on MSU-induced acute gouty arthritis in a mouse model.

METHODS

After oral administration of SHA (10 or 20 mg/kg) or the antigout medicine colchicine (0.5 mg/kg) once daily for 3 consecutive days, MSU crystals suspended in saline (2.5 mg/50 μl) were intradermally injected into the right paw of the mice. Then, SHA and colchicine were administered for another 2 days. During this period, swelling of the ankle and clinical scores were measured at 12, 24, and 48 h postinjection. After the mice were euthanized, inflammatory cytokine expression and paw tissue inflammation-related gene and protein expression, and a histopathological analysis was performed.

RESULTS

SHA had obvious therapeutic effects on MSU-induced acute gouty arthritis in mice. SHA alleviated ankle swelling and inhibited the production of cytokines, such as IL-1β and TNF-α. In addition, NLRP3, Caspase-1 and IL-1β, which are activated by MSU were also suppressed by SHA. The histological evaluation showed that SHA relieved the infiltration of inflammation around the ankle.

CONCLUSIONS

These results suggest that SHA is capable of anti-inflammatory activities and may be useful for treating gouty arthritis.

Bioinspired metal complexes for energy-related photocatalytic small molecule transformation

Bioinspired transformation of small-molecules to energy-related feedstocks is an attractive research area to overcome both the environmental issues and the depletion of fossil fuels. The highly effective metalloenzymes in nature provide blueprints for the utilization of bioinspired metal complexes for artificial photosynthesis. Through simpler structural and functional mimics, the representative herein is the pivotal development of several critical small molecule conversions catalyzed by metal complexes, e.g., water oxidation, proton and CO₂ reduction and organic chemical transformation of small molecules. Of great achievement is the establishment of bioinspired metal complexes as catalysts with high stability, specific selectivity and satisfactory efficiency to drive the multiple-electron and multiple-proton processes related to small molecule transformation. Also, potential opportunities and challenges for future development in these appealing areas are highlighted.

[The role of large-scale testing platform in the prevention and control of the COVID-19 pandemic: an empirical study based on a novel numerical model]

Objective: China adopted an unprecedented province-scale quarantine since January 23rd 2020, after the novel coronavirus (COVID-19) broke out in Wuhan in December 2019. Responding to the challenge of limited testing capacity, large-scale (>20 000 tests per day) standardized and fully-automated laboratory (Huo-Yan) was built as an ad-hoc measure. There is so far no empirical data or mathematical model to reveal the impact of the testing capacity improvement since quarantine. Methods: Based on the suspected case data released by the Health Commission of Hubei Province and the daily testing data of Huo-Yan Laboratory, the impact of detection capabilities on the realization of "clearing" and "clearing the day" of supected cases was simulated by establishing a novel non-linear and competitive compartments differential model. Results: Without the establishment of Huo-Yan, the suspected cases would increase by 47% to 33 700, the corresponding cost of quarantine would be doubled, the turning point of the increment of suspected cases and the achievement of "daily settlement" (all newly discovered suspected cases are diagnosed according to the nucleic acid testing result) would be delayed for a whole week and 11 days. If the Huo-Yan Laboratory could ran at its full capacity, the number of suspected cases could start to decrease at least a week earlier, the peak of suspected cases would be reduced by at least 44%, and the quarantine cost could be reduced by more than 72%. Ideally, if a daily testing capacity of 10 500 tests was achieved immediately after the Hubei lockdown, "daily settlement" for all suspected cases could be achieved. Conclusions: Large-scale, standardized clinical testing platform, with nucleic acid testing, high-throughput sequencing, and immunoprotein assessment capabilities, need to be implemented simultaneously in order to maximize the effect of quarantine and minimize the duration and cost of the quarantine. Such infrastructure, for both common times and emergencies, is of great significance for the early prevention and control of infectious diseases.

[Clinical value of intact parathyroid hormone levels on the first day after total thyroidectomy on prediction for permanent hypoparathyroidism]

Objective: To examine the value serum calcium and intact parathyroid hormone (iPTH) levels measured on the first day after total thyroidectomy on prediction for permanent hypoparathyroidism. Methods: Totally 546 patients with thyroid cancer and benign thyroid lesions who underwent total thyroidectomy at Department of General Surgery, Beijing Chaoyang Hospital, Capital Medical University from February 2008 to December 2018 were analyzed retrospectively. There were 158 males and 388 females aging (50.9±13.2) years (range: 19.0 to 79.2 years). Serum calcium and iPTH levels were collected before surgery, on the first day and 6 months after surgery. Logistic regression was used to analyze the correlation between each data and the occurrence of permanent hypoparathyroidism after surgery.The area under the receiver operating characteristic curve was used to evaluate the predictive power of iPTH for postoperative occurrence of permanent hypoparathyroidism. Results: Among the 546 cases of total thyroidectomy, 22 cases of permanent hypoparathyroidism occurred, with an incidence of 4.0% (22/546). Multivariate analysis showed that iPTH levels on the first day after total thyroidectomy (OR=2.932, 95%CI: 1.129 to 7.616, P=0.027) and serum calcium levels (OR=2.584, 95%CI: 1.017 to 6.567, P=0.046) were independent prognosis factors for postoperative permanent hypoparathyroidism. When the threshold value of iPTH at 24 hours after total thyroidectomy was 5.51 ng/L, the AUC was 0.956 (95%CI: 0.936 to 0.972, P=0.000), sensitivity was 100%, specificity was 85.1%, positive predictive value was 22%, negative predictive value was 100%. When the threshold value of serum calcium at 24 hours after total thyroidectomy was 1.93 mmol/L, the AUC was 0.733 (95%CI: 0.694 to 0.770, P=0.000), sensitivity was 63.6%, specificity was 78.1%, positive predictive value of 10.8% and negative predictive value of 98.1%. Conclusions: Serum iPTH and calcium levels on the first day after total thyroidectomy were related to the occurrence of permanent hypoparathyroidism postoperatively. The predictive value of iPTH level is higher than that of serum calcium level.

Thiol Activation toward Selective Thiolation of Aromatic C-H Bond

Direct C-S bond coupling is an attractive way to construct aryl sulfur ether, a building block for a variety of biological active molecules. Herein, we disclose an effective model for regioselective thiolation of the aromatic C-H bond by thiol activation instead of arene activation. Strikingly, this method has been applied into anisole derivatives that are not available in the arene activation approach to forge a single thioether isomer with high reactivity.

3312Thrombomodulin expressed on vascular smooth muscle cell influences arterial injury-induced neointima formation in mouse

Background

Thrombomodulin (TM) is a cell membrane-bound anticoagulant protein that only expresses on endothelial cells in normal artery. Vascular smooth muscle cells (SMCs) start to exhibit TM after arterial injury. Our previous study demonstrated that vascular SMC-bound TM expression was associated with SMC synthetic phenotype. TM knockdown not only attenuated aortic SMCs proliferation but also reduced aortic SMC-mediated inflammation. In this study, we investigated the effect of vascular SMC-bound TM on arterial injury-induced neointima formation in mouse.

Methods and results

Because complete loss of TM in TM knockout transgenic mice causes embryonic lethality, we generated vascular SMC-specific TM-deficient mice (SM22-cretg/TMflox/flox) and their wild-type controls (SM22-cretg/TM+/+) using the Cre-loxP system to explore the role of vascular SMC membrane-bound TM in vivo. The blood pressure and body weight were similar between SM22-cretg/TMflox/flox mice and their wild-type controls. Carotid ligation caused neointima formation in mice. Immunofluorescence staining showed that there was large amount TM expression in the medial and neointimal cells at 4 weeks in SM22-cretg/TM+/+ mice after carotid ligation, but there was no TM staining could be found in SM22-cretg/TMflox/flox mice. There was a progressively increased neointima area from 2 to 4 weeks after carotid ligation both in SM22-cretg/TMflox/flox mice and SM22-cretg/TM+/+ mice, but the neointima area and neointima/media area ratio were significantly smaller in SM22-cretg/TMflox/flox mice than SM22-cretg/TM+/+ mice. Immunofluorescence staining showed that there were less Ki67-positive cells in the media and neointima in SM22-cretg/TMflox/flox mice indicating less proliferating cells in the arterial wall of TM-deficient mice. The α-smooth muscle actin-positive staining area was also larger in the SM22-cretg/TMflox/flox mice, suggesting TM deficiency of SMCs in medial lesion exhibited a more contractile status after carotid ligation.

Conclusions

Our results indicated that vascular SMC-bound TM not only mediated vascular SMC phenotype change and cell behavior but also significantly influenced arterial injury-induced neointima formation.

Acknowledgement/Funding

This study was sponsored by grants 104-2314-B-006-083-MY2 and 106-2314-B-006-045-MY3 from the Ministry of Science and Technology, Taipei, Taiwan.

Semiconductor Quantum Dots: An Emerging Candidate for CO2 Photoreduction

As one of the most critical approaches to resolve the energy crisis and environmental concerns, carbon dioxide (CO₂ ) photoreduction into value-added chemicals and solar fuels (for example, CO, HCOOH, CH₃ OH, CH₄ ) has attracted more and more attention. In nature, photosynthetic organisms effectively convert CO₂ and H₂ O to carbohydrates and oxygen (O₂ ) using sunlight, which has inspired the development of low-cost, stable, and effective artificial photocatalysts for CO₂ photoreduction. Due to their low cost, facile synthesis, excellent light harvesting, multiple exciton generation, feasible charge-carrier regulation, and abundant surface sites, semiconductor quantum dots (QDs) have recently been identified as one of the most promising materials for establishing highly efficient artificial photosystems. Recent advances in CO₂ photoreduction using semiconductor QDs are highlighted. First, the unique photophysical and structural properties of semiconductor QDs, which enable their versatile applications in solar energy conversion, are analyzed. Recent applications of QDs in photocatalytic CO₂ reduction are then introduced in three categories: binary II-VI semiconductor QDs (e.g., CdSe, CdS, and ZnSe), ternary I-III-VI semiconductor QDs (e.g., CuInS₂ and CuAlS₂ ), and perovskite-type QDs (e.g., CsPbBr₃ , CH₃ NH₃ PbBr₃ , and Cs₂ AgBiBr₆ ). Finally, the challenges and prospects in solar CO₂ reduction with QDs in the future are discussed.

[Carcinogenicity study of CD133(+)CD44(+) laryngeal cancer stem cells and identification of related microRNAs]

Objective: To compare the carcinogenic abilities of CD133(+)CD44(+) laryngeal cancer stem cells and general laryngeal cancer stem cells and to identify the mechanism underlying the action of miRNAs. Methods: Solid tumor-derived laryngeal carcinoma stem cells and Hep-2-derived laryngeal carcinoma stem cells were cultured, and CD133(+)CD44(+) laryngeal cancer stem cells were sorted by flow cytometry. Boden chamber invasion assay, cell migration assay and tumor formation assay were then performed to compare the invasion, migration and tumorigenic abilities of CD133(+)CD44(+) laryngeal cancer stem cells and general laryngeal cancer stem cells. And then, miRNAs isolated from two laryngeal cancer stem cells were detected and analysed with miRNA chip. Results: (1)In Boyden chamber invasion assay, the cell invasion rate of CD133(+)CD44(+) laryngeal cancer stem cells was obviously higher (80.2%±2.3% vs. 63.9%±3.2%, t=5.011, P=0.027); (2)CD133(+)CD44(+) laryngeal cancer stem cells also had higher mobility in cell migration assay (82.9%±1.1% vs. 70.9%±0.6%, t=4.514, P=0.031); (3)In tumor formation assay, the tumor formation rate of CD133(+)CD44(+) laryngeal cancer stem cells was also higher (80% vs. 50%). What's more, we identified 15 miRNAs that were significantly upregulated in CD133(+)CD44(+) laryngeal cancer stem cells and 3 miRNAs that were significantly downregulated in CD133(+)CD44(+) laryngeal cancer stem cells, compared with normal laryngeal cancer stem cells. Conclusions: CD133(+)CD44(+) laryngeal cancer stem cells have stronger invasion, migration and tumorigenic abilities compared with normal laryngeal cancer stem cells, and the difference of miRNAs' expression is one of the possible causes.

Photoelectrochemical cell for P–H/C–H cross-coupling with hydrogen evolution

A photoelectrochemical cell is able to save nearly 90% external bias input to realize activation of P–H/C–H bonds for cross-coupling hydrogen evolution as compared with an electrochemical cell.

[Clinical experience and next-generation sequencing analysis of encephalitis caused by pseudorabies virus]

Objective: To detect potential pathogens including pseudorabies virus in patients with encephalitis of unknown etiology in China and describe novel encephalitic entities. Methods: Patients with clinically suspected infectious encephalitis were enrolled in a multicenter study to identify the pathogens in PUMCH Encephalitis Program.Next-generation sequencing(NGS) of cerebrospinal fluid (CSF) was used in patients with encephalitis of unknown etiology enrolled from 2016 to 2017.The patients diagnosed as PRV encephalitis were studied to describe this novel entity. Results: The four patients(3 male, 1 male, 38-54 years old) had occupational exposure to raw park when working in the production or marketing of pork and at least one got injured during pork-cutting.Two of them were confirmed with NGS of CSF, and anti-PRV antibodies were positive in 3 patients whose serum was available for serological analysis.They all presented with an acute onset of fever, convulsion, loss of consciousness and respiratory failure within 1 to 4 days and rapidly deteriorated even on extensive treatment.All the patients needed ICU admission and 3 needed mechanical ventilation.Two patients also had bilateral retinitis.Neuroimaging revealed symmetric gray matter lesions including limbic system, basal ganglia and midbrain without obvious hemorrhage.Lumbar puncture revealed elevated intracranial pressure and lymphocytic pleocytosis [(6-64)×10(6)/L] of CSF.The patients failed to response to the treatment of acyclovir combined with intravenous immunoglobulin and steroids.Modified Rankin Score was 3, 5, 5 and 6 (died) for the 4 patients respectively on last follow-up. Conclusions: PRV could be a cause of severe encephalitis.The patients with suspected pseudorabies encephalitis (PRE) need to be tested for PRV DNA timely.Severe encephalitis with bilateral involvement of limbic system, basal ganglion, thalamus and midbrain in patient with occupational exposure indicate this emerging infectious encephalitis.

Comparative Proteomics Reveal the Association between SPANX Proteins and Clinical Outcomes of Artificial Insemination with Donor Sperm

Semen analysis is used for diagnosing male infertility and evaluating male fertility for more than a century. However, the semen analysis simply represents the population characteristics of sperm. It is not a comprehensive assessment of the male reproductive potential. In this study, 20 semen samples from human sperm bank with distinctive artificial insemination with donor sperm (AID) clinical outcomes were collected and analyzed using a two-dimensional differential in-gel electrophoresis (2D-DIGE); 45 differentially expressed protein spots were obtained, and 26 proteins were identified. Most differentially expressed proteins were related to sperm motility, energy consumption, and structure. These identified proteins included several sperm proteins associated with the nucleus on the X chromosome (SPANX) proteins. This prospective study aimed to investigate the association between the expression levels of SPANX proteins and the AID clinical outcomes. The proteins identified in this study provided a reference for the molecular mechanism of sperm fertility and revealed a predictive value of the SPANX proteins.

Assembling metallic 1T-MoS2 nanosheets with inorganic-ligand stabilized quantum dots for exceptional solar hydrogen evolution

Due to their enhanced light harvesting, favored interfacial charge transfer and excellent proton reduction activity, hybrid photocatalysts of metallic 1T-MoS₂ nanosheets and inorganic-ligand stabilized CdSe/ZnS QDs obtained via a self-assembly approach can produce H₂ gas with a rate of ∼155 ± 3.5 μmol h^-1 mg^-1 under visible-light irradiation (λ = 410 nm), the most exceptional performance of solar H₂ evolution using MoS₂ as a cocatalyst known to date.

Enhanced Charge Separation Efficiency Accelerates Hydrogen Evolution from Water of Carbon Nitride and 3,4,9,10-Perylene-tetracarboxylic Dianhydride Composite Photocatalyst

The catalytic ability of graphitic carbon nitride is greatly affected by its intrinsic electronic properties. Although combination with chromophore has been demonstrated to be one of the promising approaches to improve the catalytic performance of carbon nitride, it is imperative to understand the key factors governing the whole process. Here, we report a composite photocatalyst CN-P by embedding perylene unit into the matrix of carbon nitride. The composite photocatalyst could catalyze hydrogen evolution with a high rate of 17.7 mmol h^-1 g^-1, which is 2.8 times faster than pure carbon nitride. The apparent quantum efficiency is high up to be 5.8% at 450 nm. Detailed studies reveal that the light absorption ability and charge separation efficiency are greatly enhanced in the synthesized catalyst. These are the key factors for the improved hydrogen evolution ability of CN-P than that of pure carbon nitride.

Self-assembled inorganic clusters of semiconducting quantum dots for effective solar hydrogen evolution

The catalytic activity of CdSe QDs could be enhanced more than 150-fold by forming self-assembled clusters with ZnSe QDs madeex situ.

Quantitative Identification of Compound-Dependent On-Modules and Differential Allosteric Modules From Homologous Ischemic Networks

Module‐based methods have made much progress in deconstructing biological networks. However, it is a great challenge to quantitatively compare the topological structural variations of modules (allosteric modules [AMs]) under different situations. A total of 23, 42, and 15 coexpression modules were identified in baicalin (BA), jasminoidin (JA), and ursodeoxycholic acid (UA) in a global anti‐ischemic mice network, respectively. Then, we integrated the methods of module‐based consensus ratio (MCR) and modified Z_summary module statistic to validate 12 BA, 22 JA, and 8 UA on‐modules based on comparing with vehicle. The MCRs for pairwise comparisons were 1.55% (BA vs. JA), 1.45% (BA vs. UA), and 1.27% (JA vs. UA), respectively. Five conserved allosteric modules (CAMs) and 17 unique allosteric modules (UAMs) were identified among these groups. In conclusion, module‐centric analysis may provide us a unique approach to understand multiple pharmacological mechanisms associated with differential phenotypes in the era of modular pharmacology.

Improved Photoelectrocatalytic Performance for Water Oxidation by Earth-Abundant Cobalt Molecular Porphyrin Complex-Integrated BiVO4 Photoanode

An earth-abundant, low-cost cobalt porphyrin complex (CoTCPP) is designed as a molecular catalyst to work on three-dimensional BiVO4 film electrode for water oxidation for the first time. Under illumination of a 100 mW cm(-2) Xe lamp, the CoTCPP-functionalized BiVO4 photoanode exhibits a 2-fold enhancement in photocurrent density at 1.23 V vs RHE and nearly a 450 mV cathodic shift at 0.5 mA cm(-2) photocurrent density relative to bare BiVO4 in 0.1 M Na2SO4 (pH = 6.8). Simultaneously, stoichiometric oxygen and hydrogen are generated with a faradic efficiency of 80% over 4 h. The activity and stability of the BiVO4 photoanode are dramatically increased by molecular CoTCPP, giving rise to higher performance than previously reported noble metal ruthenium complex-modified BiVO4 photoanode. By using hydrogen peroxide as the hole scavenger, we demonstrate that molecular CoTCPP catalyst greatly suppresses the hole-electron recombination on the surface of BiVO4 semiconductor, which offers a promising route toward high efficiency, low cost, practical solar fuel generation device.

Hole-Accepting-Ligand-Modified CdSe QDs for Dramatic Enhancement of Photocatalytic and Photoelectrochemical Hydrogen Evolution by Solar Energy

Solar H2 evolution of CdSe QDs can be significantly enhanced simply by introducing a suitable hole-accepting-ligand for achieving efficient hole extraction and transfer at the nanoscale interfaces, which opens an effective pathway for dissociation of excitons to generate long-lived charge separation, thus improving the solar-to-fuel conversion efficiency.

Relationship between TLR4 and CCL2 expression and recurrent spontaneous abortion

The increasing incidence of recurrent spontaneous abortion (RSA) severely affects women's health. The involvement of the immune system during pregnancy and its contribution to RSA draw researchers' attention. Both Toll-like receptor 4 (TLR4) and chemokine (C-C motif) ligand 2 (CCL2) have been linked to various pregnancy disorders. In this study, we quantified TLR4 and CCL2 levels in a case-control study in order to elucidate the correlation between these factors and RSA, and the potential to use them as disease markers. A total of 36 RSA patients and 36 healthy control individuals were recruited for the donation of decidual and chorionic tissues and venous blood samples. Fluorescent quantitative-polymerase chain reaction was used to measure mRNA levels and enzyme linked immunosorbent assay was used to quantify serum levels of TLR4 and CCL2. RSA patients had higher TLR4 and CCL2 mRNA levels compared to controls (P < 0.05). Serum levels of the two factors were also significantly higher in RSA patients than in the control group (P < 0.05). Positive correlations were found between serum levels and tissue mRNA levels of TLR4 and CCL2. In conclusion, both TLR4 and CCL2 were closely related to the occurrence of RSA, suggesting that serum TLR4 and CCL2 levels could be used as indices for monitoring RSA in pregnant women.

Clinical efficacy of fiberoptic ductoscopy in combination with ultrasound-guided minimally invasive surgery in treatment of plasma cell mastitis

OBJECTIVES

To analyze clinical efficacy between fiberoptic ductoscopy plus ultrasound-guided minimally invasive irrigation and lesion resection in treating plasma cell mastitis (PCM), aiming to provide clinical evidence for treating PCM.

MATERIALS AND METHODS

119 patients undergoing fiberoptic ductoscopy plus ultrasound-guided minimally invasive surgery in Ningxia People's Hospital were allocated into the breast duct irrigation group, and 95 counterparts receiving lesion resection in the Affiliated Hospital of Ningxia Medical University into the control group. Clinico-pathological characteristics and therapeutic effect were compared between two groups.

RESULTS

The cure rate in the breast duct irrigation group was 98.31% (117/119), significantly higher than 90.53% in the control group (p < 0.05). In the breast duct irrigation group, overall treatment time was 20.13 days, significantly longer than 15.15 days in the control group (p < 0.05). During postoperative follow-up, no recurrence was observed, significantly lower compared with 48.8% (42/86) in the control group. The degree of satisfaction in the breast duct irrigation group was 95.79% (114/119), significantly higher compared with 74.74% (71/95) in the control group.

CONCLUSIONS

Fiberoptic ductoscopy plus with ultrasound-guided minimally invasive drainage is a novel and effective treatment of PCM with high cure rate, low recurrence rate, slight pain, and effectively maintains breast integrity.

Cloning and stress response analysis of the PeDREB2A and PeDREB1A genes in moso bamboo (Phyllostachys edulis)

Moso bamboo is a large woody bamboo with the highest ecological, economic, and cultural value among all bamboos in Asia. However, environmental stress influences its growth and development and limits its geographic distribution. Therefore, improving its resistance to environmental stress is extremely important. Dehydration responsive element binding (DREB) transcription factors perform an important role in the regulation of stress-related genes, enhancing the resistance of plants to abiotic stress. In the current study, two novel DREB genes, PeDREB2A and PeDREB1A (Gene ID No. PH01000046G1730 and PH01000668G0350), were isolated from moso bamboo and the sequences were identified and characterized (coding sequence lengths were 795 and 825 bp, respectively). The PeDREB2A and PeDREB1A proteins were estimated to have typical AP2/ERF domains, molecular weights of 28.96 and 28.84 kDa, and isoelectric points of 9.47 and 5.34, respectively. RT-PCR analysis revealed that PeDREB2A and PeDREB1A were tissue-specific genes, expressed in leaves, young stems, and roots, with similar expression levels in leaves and young stems. qRT-PCR analysis of leaves demonstrated that PeDREB2A transcription levels rapidly accumulate following exposure to drought and salt stress, peaking at 12 and 0.5 h, respectively, but only low expression levels were observed under cold stress. PeDREB1A exhibited a strong response to cold stress, reaching a peak in expression 3 h after exposure, but demonstrated only a slight response to drought and salt stress. In roots, PeDREB2A was down-regulated, and PeDREB1A was initially upregulated but then declined, under stress conditions. Two plant expression vectors, pCAMBIA2300- CaMV35S-PeDREB2A and pCAMBIA2300-CaMV35S-PeDREB1A were also successfully constructed.

Molecular cloning, characterisation and tissues expression analysis of the goose (Anser cygnoides) vasoactive intestinal peptide (VIP) gene

1. Vasoactive intestinal peptide (VIP) is involved in the control of prolactin (PRL) release and plays a pivotal role as a regulator of reproductive behaviour and neuroendocrine secretion in birds. 2. In this study, a 941-bp cDNA fragment covering the complete coding region (CDS) of goose VIP gene was identified. The cDNA contains a 32-bp 5'-untranslated region (UTR), a 603-bp CDS and a 306-bp 3'-UTR containing two ATTTA sequence elements, two polyadenylation signals (AATAAA) and a 25-bp poly (A) tail. 3. Seven exons and 6 introns were identified, and both the cDNA and genomic DNA sequences showed high identity with those of other species. 4. The sequence analysis indicated that there were two alternatively spliced transcripts the long transcript (VIP-1) encoded both VIP and peptide histidine isoleucine exons and the short one (VIP-2) only encoded VIP. 5. RT-PCR analysis indicates that the expression level of the VIP-1 is much lower than that of VIP-2, and that VIP-1 is negligible or absent in muscle, abdominal fat, ovary and spleen, whereas VIP-2 is widely distributed in all the examined tissues. 6. A total of 12 single nucleotide polymorphisms (SNPs), including 2 SNPs located in the coding region and 10 variations in intron regions, were identified in goose VIP gene.

The effectiveness of an integrated multicomponent program for adolescent smoking cessation in Taiwan

If adolescents do not receive appropriate assistance in quitting smoking, they are highly likely to become regular smokers when they enter adulthood. Thus, an effective smoking-cessation program is required. A program was designed based on both the smoking-cessation barriers reported by students and effective strategies derived from the literature. We assigned 143 student smokers from 6 vocational high schools to intervention (n=78) and comparison groups (n=65). Data were collected at the baseline, the end of the program, and 1- and 4-month follow-up time points. For the intervention group, the smoking-abstinence rates confirmed using the urine cotinine test were 22.73% at the end of the program and 20.75% at the 4-month follow-up point. Days smoked in the past month, number of cigarettes smoked per day, and the Fagerström Test for Nicotine Dependence score of the intervention group decreased at all of the time points. The group differences in these variables were statistically significant; the magnitude of effect sizes ranged from 0.44 to 0.95. Multicomponent programs addressing smoking-cessation barriers that students encounter can help adolescents quit smoking.

Molecular cloning, expression and polymorphism of goose LRP8 gene

1. The low-density lipoprotein receptor-related protein 8 (LRP8), a member of the low-density lipoprotein receptor (LDLR) gene family, participates in the supplying of lipid during follicular development. The objective of the study was to identify and characterise the LRP8 gene in goose. 2. A 2867 bp fragment that covered the complete coding region (CDS) of goose (Anser cygnoides) LRP8 gene was cloned. It encoded a protein of 917 amino acid residues containing a 24-amino acid signal peptide and 5 functional domains. The goose LRP8 showed high nucleic acid and amino acid identities with those in other species. 3. Similarly to duck LRP8 gene, two splice variants of LRP8, LRP8-1 (containing 8 ligand-binding repeats) and LRP8-2 (containing 7 ligand-binding repeats), were identified in goose. 4. Semi-quantitative RT-PCR analysis indicates that the LRP8-1 transcript is expressed in heart, liver, spleen, lung, kidney, breast muscle, duodenum, hypothalamus, pituitary and ovary, negligible or absent in sebum and oviduct, and the LRP8-2 transcript is widely expressed in all examined tissues. 5. A total of 7 SNPs were identified in the coding region of the goose LRP8 gene.

Coupled vectors resolution method for chemometric calibration with three-way data

A new second-order calibration procedure, the coupled vectors resolution (COVER) method, has been developed. The objective of the method is to seek a couple of vectors that minimize a least-squares criterion. With the knowledge indispensable for quantitation, the method yields direct solutions to various cases of second-order calibration. Moreover, it allows a statistically plausible way to make use of multisample information. In the case of multiple calibration samples, the method uses the calibration samples to resolve the profiles of the analytes in each order, and then calculates the concentrations of the analytes. This offers the advantage that unknown mixtures newly collected can be predicted in a direct manner. In the case of one calibration sample, the method provides an effective way to utilize the information of spectral profiles of the analytes. Results of simulated experiments and a real analytical example show that the proposed method produces acceptable performance in profile resolution and concentration estimation.

Inter-unit variability in two ParvoMedics TrueOne 2400 automated metabolic gas analysis systems

Knowing the inter-unit variability, especially the technological error, is important when using many physiological measurement systems, yet no such inter-unit analysis has been undertaken on duplicate automated gas analysis systems. This study investigated the inter-unit performance of two identical ParvoMedics TrueOne 2400 automated gas analysis systems during a range of submaximal steady-state exercises performed on an electromagnetic cycle ergometer. Fifteen adult males were tested on two separate days a rest, 30, 60, 90, and 120 Watts with the duplicate gas analysis units arranged (1) collaterally (2 min of steady-state expired gas was alternately passed through each system), and (2) simultaneously (identical steady-state expired gas was passed simultaneously through both systems). Total within-subject variation (biological + technological) was determined from the collateral tests, but the unique inter-unit variability (technological error between identical systems) was shown by the simultaneous tests. Absolute percentage errors (APE), coefficient of variations (CV), effect sizes and Bland-Altman analyses were undertaken on the metabolic data, including expired ventilation (V (E)), oxygen consumption (VO(2)) and carbon dioxide production (VCO(2)). The few statistically significant differences detected between the two duplicate systems were determined to have small or trivial effect sizes, and their magnitudes to be of little physiological importance. The total within-subject variations for VO(2), VCO(2) and V (E) each equated to a mean CV and mean APE value of ~4 and ~6 %, whilst the respective inter-unit technological errors equated to ~1.5 and ~2.1 %. The two ParvoMedics TrueOne 2400 systems demonstrated excellent inter-unit agreement.

Isolation and characterization of eight polymorphic microsatellite loci for the coconut pest, Brontispa longissima (Coleoptera: Hispidae)

Brontispa longissima is one of the most serious insect pests of coconut in Southeast Asia; it was first discovered on Hainan Island in June 2002. Despite the economic risk associated with this pest, genetic aspects of the invasion process have remained relatively unexplored. Using microsatellite markers, we investigated the population structure, genetic variability and pattern of invasion in various geographic populations. The methodology was based on a modified biotin-capture method. Eight polymorphic microsatellite loci were isolated and characterized for the pest. The allele number per locus varied from 2 to 3 (N = 30). The expected and observed heterozygosities of the eight loci ranged from 0.042 to 0.509 and from 0.042 to 0.963, respectively. Although the frequency of polymorphisms was not very high in this population, the microsatellite loci that were isolated will be useful for investigating the genetic diversity and migration routes of B. longissima populations.

Generation of a novel factor IX with augmented clotting activities in vitro and in vivo

BACKGROUND

Hemophilia B is an X-linked inherited disorder caused by the lack of functional factor IX (FIX). Currently, treatment of hemophilia B is performed by intravenous infusion of plasma-derived or recombinant FIX.

OBJECTIVE

In an effort to reduce factor usage and cost, we investigated the potential use of FIX variants with enhanced specific clotting activity.

METHODS

Seven recombinant FIX variants using alanine replacement were generated and assayed for their activity in vitro and in vivo.

RESULTS

One variant containing three substitutions (V86A/E277A/R338A, FIX-Triple) exhibited 13-fold higher specific clotting activity and a 10-fold increased affinity for human FVIIIa compared with FIX-wild-type (FIX-WT) and was thus investigated systematically in vivo. Liver-specific FIX-Triple gene expression following hydrodynamic plasmid delivery revealed a 3.5-fold higher specific clotting activity compared with FIX-WT. Human FIX-Triple and FIX-WT knock-in mice were generated and it was confirmed that FIX-Triple has 7-fold higher specific clotting activity than FIX-WT under normal physiological conditions. Protein infusion of FIX-Triple into hemophilia B mice resulted in greater improvement of hemostasis than that achieved with FIX-WT. Moreover, tail-vein administration of a serotype 8 recombinant Adeno-associated vector (AAV8) expressing either FIX-WT or FIX-Triple in hemophilia B mice demonstrated a 7-fold higher specific clotting activity of FIX-Triple than FIX-WT.

CONCLUSIONS

Our results indicate that the FIX-Triple variant exhibits significantly enhanced clotting activity relative to FIX-WT due to tighter binding to FVIIIa, as demonstrated both in vitro and in vivo. Therefore, FIX-Triple is a good candidate for further evaluation in protein replacement therapy as well as gene-based therapeutic strategies.

Ageing of alpha-chymotrypsin: Cannibalistic and hydroxide ion reactions

The loss of catalytic activity (irreversible denaturation) of alpha-chymotrypsin (EC 3.4.21.1) as a function of pH between 6 and 13 is described. Around neutrality the irreversible denaturation is second order with respect to enzyme. At high pH, the irreversible denaturation is first order with respect to enzyme and also with respect to hydroxide ion. The first- or second-order dependency on enzyme concentration has been shown both by the time course of denaturation and by the effect of enzyme concentration on the rate of denaturation. The first-order dependency on hydroxide ion was shown by a plot of the logarithm of the rate constant vs. pH. These enzyme inactivations are peptide bond cleavages at all pH values. From the kinetics, the irreversible denaturation can be described as a cannibalistic reaction of two enzyme molecules around neutrality or as a reaction of one enzyme molecule plus one hydroxide ion at high pH.

Elimination of cannibalistic denaturation by enzyme immobilization or inhibition

The cannibalistic denaturation of alpha-chymotrypsin (EC 3.4.21.1) around neutral pH can be eliminated by immobilization (insolubilization) of the enzyme or by inhibition by specific reversible inhibitors, but the high-pH denaturation cannot be. The denaturation of the immobilized enzyme at high pH follows first-order kinetics, just as the denaturation of the soluble enzyme does. These results lend credence to the description of the denaturation of chymotrypsin as cannibalistic around neutrality and due to a hydroxide ion reaction at high pH; this interpretation followed from kinetic arguments given in the previous article [Wu, H.-L., Wastell, A. & Bender, M. L. (1981) Proc. Natl. Acad. Sci. USA 78, 4116-4117]. Elimination of denaturation around neutrality by immobilization may be the reason why membrane-bound enzymes are so common in vivo.

Human plasminogen kringle 1-5 reduces atherosclerosis and neointima formation in mice by suppressing the inflammatory signaling pathway

BACKGROUND

Activation of vascular endothelial cells plays an important role in atherogenesis and plaque instability. Recent research has demonstrated that late-stage inhibition of plaque angiogenesis by angiostatin (kringle 1-4) reduces macrophage accumulation and slows the progression of advanced atherosclerosis. Kringle 1-5 (K(1-5)) is a variant of angiostatin that contains the first five kringle domains of plasminogen.

OBJECTIVE

To investigate whether K(1-5) has an inhibitory effect on early-stage atherosclerosis, using the apolipoprotein E (ApoE)-deficient mouse model and a carotid artery ligation model.

METHODS

ApoE-deficient mice received K(1-5) treatment for 4 weeks, and the severity of aortic atherosclerosis was measured. In the ligation model, the left common carotid arteries of C57BL/6 mice were ligated near the carotid bifurcation, and the mice received K(1-5) for 4 weeks. Human umbilical vein endothelial cells were pretreated with K(1-5) before tumor necrosis factor-alpha (TNF-alpha) treatment to explore the anti-inflammatory effect of K(1-5).

RESULTS

The areas of the lesion in the aortas of ApoE-deficient mice that received K(1-5) treatment were notably decreased, and the formation of carotid neointima in the C57BL/6 mice was decreased by treatment with K(1-5). Expression of TNF-alpha-induced intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 was inhibited by K(1-5) treatment, possibly via downregulation of translocation of nuclear factor-kappaB and expression of reactive oxygen species.

CONCLUSIONS

K(1-5) reduced atherosclerosis and neointima formation in mice, possibly through inhibition of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 expression in endothelial cells.

A new procedure for correction of severe inverted nipple with two triangular areolar dermofibrous flaps

Severely inverted nipples are invaginated deeply and present many aesthetic, functional, and psychological problems. Many methods have been proposed for correction of this deformity. The authors describe a new simple method using two broad triangular areolar dermofibrous flaps. This method affords sufficient tissue to fill the dead space. Furthermore, it furnishes bulk to drive up the nipple, and because the cross lay of the flap and the epidermis make the areola circular and small, it provides sufficient areolar tissue for reconstruction of the defective nipple. The manipulation of postoperative "donut" traction is simple and useful. This method was used to correct 14 nipples of 9 patients successfully without any postoperative problems and with minimal scars and no recurrence of inversion. It is an ideal surgical procedure for the severely inverted nipple.

Hydroxychavicol, a novel betel leaf component, inhibits platelet aggregation by suppression of cyclooxygenase, thromboxane production and calcium mobilization

BACKGROUND AND PURPOSE

Platelet hyperactivity is important in the pathogenesis of cardiovascular diseases. Betel leaf (PBL) is consumed by 200-600 million betel quid chewers in the world. Hydroxychavicol (HC), a betel leaf component, was tested for its antiplatelet effect.

EXPERIMENTAL APPROACH

We tested the effect of HC on platelet aggregation, thromboxane B(2) (TXB(2)) and reactive oxygen species (ROS) production, cyclooxygenase (COX) activity, ex vivo platelet aggregation and mouse bleeding time and platelet plug formation in vivo. The pharmacokinetics of HC in rats was also assessed.

KEY RESULTS

HC inhibited arachidonic acid (AA) and collagen-induced platelet aggregation and TXB(2) production. HC inhibited the thrombin-induced TXB(2) production, but not platelet aggregation. SQ29548, suppressed collagen- and thrombin-induced TXB(2) production, but not thrombin-induced platelet aggregation. HC also suppressed COX-1/COX-2 enzyme activity and the AA-induced ROS production and Ca(2+) mobilization. HC further inhibited the ex vivo platelet aggregation of platelet-rich plasma (>100 nmole/mouse) and prolonged platelet plug formation (>300 nmole/mouse) in mesenteric microvessels, but showed little effect on bleeding time in mouse tail. Moreover, pharmacokinetics analysis found that more than 99% of HC was metabolized within 3 min of administration in Sprague-Dawley rats in vivo.

CONCLUSIONS AND IMPLICATIONS

HC is a potent COX-1/COX-2 inhibitor, ROS scavenger and inhibits platelet calcium signaling, TXB(2) production and aggregation. HC could be a potential therapeutic agent for prevention and treatment of atherosclerosis and other cardiovascular diseases through its anti-inflammatory and antiplatelet effects, without effects on haemostatic functions.

Post-translational modification of delta antigen of hepatitis D virus

The hepatitis delta virus (HDV) genome has only one open reading frame, which encodes the viral small delta antigen. After RNA editing, the same open reading frame is extended 19 amino acids at the carboxyl terminus and encodes the large delta antigen. These two viral proteins escort the HDV genome through different cellular compartments for the complicated phases of replication, transcription and, eventually, the formation of progeny virions. To orchestrate these events, the delta antigens have to take distinct cues to traffic to the right compartments and make correct molecular contacts. In eukaryotes, post-translational modification (PTM) is a major mechanism of dictating the multiple functions of a single protein. Multiple PTMs, including phosphorylation, isoprenylation, acetylation, and methylation, have been identified on hepatitis delta antigens. In this chapter we review these PTMs and discuss their functions in regulating and coordinating the life cycle of HDV.

Reactive oxygen species are crucial for hydroxychavicol toxicity toward KB epithelial cells

Betel quid (BQ) chewing shows a strong correlation to the incidence of oral submucous fibrosis (OSF), leukoplakia and oral cancer. BQ contains mainly areca nut, lime, Piper betle leaf (PBL) and the inflorescence of P. betle (IPB). Hydroxychavicol (4-allyl-catechol, HC), as a major phenolic compound in PBL and IPB, is shown to induce oxidative stress, glutathione (GSH) depletion and cell cycle deregulation. Using bivariate BrdU/PI flow cytometry, KB cells in DNA synthesis (S phase) are shown to be sensitive to the toxic effect of HC and show cell cycle arrest and apoptosis following exposure to 0.1 and 0.3 mM HC. HC-induced apoptosis and cell cycle arrest are associated with mitochondrial membrane potential (delta Psim) depolarization as revealed by a decrease in rhodamine fluorescence. N-acetyl-L-cysteine (1 mM), superoxide dismutase (100 U/ml) and catalase (1000 U/ml) were effective in prevention of HC-induced GSH depletion (as indicated by chloromethylfluorescein fluorescence), reactive oxygen species (ROS) production (by dichlorofluorescein fluorescence), cell cycle arrest and apoptosis. However, dimethylthiourea (2 mM), neocuproine (1 mM), 1,10-phenanthroline (200 microM) and desferrioxamine (0.5 mM) showed little effect on HC-induced cell changes. HC elevated the cellular and mitochondrial GSH levels at moderate concentrations (0.05-0.1 mM), whereas at a concentration of 0.3 mM, inhibitory effects were noted. These results indicate that HC consumption may be associated with BQ-chewing-related oral mucosal diseases via GSH depletion, ROS production, mitochondrial dysfunction, cell cycle disturbance and the induction of apoptosis. These events are related to the production of superoxide radicals and hydrogen peroxide.

Identification of rice black streaked dwarf virus in different cereal crops with dwarfing symptoms in China

This report describes isolation of virus particles from plants of rice, maize, wheat and sorghum with symptoms of dwarfing collected from two provinces of China, purification of double-stranded RNA (dsRNA) from the virus particles, and synthesis of full-length cDNAs of genome segments 9 (S9) and 10 (S10) by reverse transcription-polymerase chain reaction (RT-PCR). Sequence analysis showed that the S9 sequences of the Chinese isolates and a Japanese rice black-streaked disease virus (RBSDV) isolate were very similar (89.1-89.6% homology at nucleotide level and 92.3-92.9% and 95.8-98.6% homology at amino acid level for ORF1 and ORF2, respectively). Analogical similarity was found also for the S10 sequences of the isolates under comparison: 93.0-95.4% homology at nucleotide level and 96.2-97.0% homology at amino acid level. However, there was a relatively lower similarity for S9 and S10 segments ofthe Chinese isolates and an Italian maize rough dwarf virus (MRDV) isolate. The phylogenetic analysis indicated that the Chinese isolates that infect rice, maize, wheat and sorghum and cause similar symptoms could represent the same virus species, RBSDV.

Studies of a novel human thrombomodulin immobilized substrate: surface characterization and anticoagulation activity evaluation

Immobilization of the anticoagulative or antithrombogenic biomolecule has been considered as one of the important methods to improve the blood compatibility of artificial biomaterials. In this study, a novel immobilization reaction scheme was utilized to incorporate the human thrombomodulin, an endothelial cell associated glycoprotein, onto the cover glass surface with an aim to develop an anticoagulative substrate. Trichlorotriazine and amino-terminated silane were employed as the coupling agents, while the polyethylene glycol with a molecular weight of 1500 was used as the spacer in this reaction scheme. Protein C activation assay indicated the immobilized human thrombomodulin still has this coenzymatic activity but is lower, possibly due to the conformation variation by the coupling agents. In vitro platelet adhesion assay has demonstrated the surface with immobilized human thrombomodulin is much less platelet-activating than others. Therefore, the novel reaction scheme proposed here is very promising for future development of an anticoagulative silicon or cover glass substrate (e.g. implantable sensor or biochip) by the immobilization of antithrombogenic protein, such as the human thrombomodulin in this study.

Inducing the cell cycle arrest and apoptosis of oral KB carcinoma cells by hydroxychavicol: roles of glutathione and reactive oxygen species

Hydroxychavicol (HC; 10 - 50 microM), a betel leaf component, was found to suppress the 2% H(2)O(2)-induced lucigenin chemiluminescence for 53 - 75%. HC (0.02 - 2 microM) was also able to trap superoxide radicals generated by a xanthine/xanthine oxidase system with 38 - 94% of inhibition. Hydroxyl radicals-induced PUC18 plasmid DNA breaks was prevented by HC (1.6 - 16 microM). A 24-h exposure of KB cells to HC (0.5, 1 mM) resulted in 54 - 74% cell death as analysed by a 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. HC (10, 50 microM) further suppressed the growth of KB cells (15 and 76%, respectively). Long-term colony formation of KB cells was inhibited by 51% with 10 microM HC. Pretreatment of KB cells with 100 microM HC inhibited the attachment of KB cells to type I collagen and fibronectin by 59 and 29%, respectively. Exposure of KB cells to 0.1 mM HC for 24 h resulted in cell cycle arrest at late S and G2/M phase. Increasing the HC concentration to 0.25 and 0.5 mM led to apoptosis as revealed by detection of sub-G(0)/G(1) peaks with a concomitant decrease in the number of cells residing in late S and G(2)/M phase. Inducing the apoptosis of KB cells by HC was accompanied by marked depletion in reduced form of GSH (>0.2 mM) and the increasing of reactive oxygen species production (>0.1 mM) as analysed by CMF- and DCF-single cell fluorescence flow cytometry. These results indicate that HC exerts antioxidant property at low concentration. HC also inhibits the growth, adhesion and cell cycle progression of KB cells, whereas its induction of KB cell apoptosis (HC>0.1 mM) was accompanied by cellular redox changes.

Molecular cloning and expression of woodchuck granulocyte-macrophage colony stimulating factor

Granulocyte-macrophage colony stimulating factor (GM-CSF) has immunoregulatory and antiviral effects, and may thus be promising for the treatment of chronic hepatitis B. Using woodchuck hepatitis virus (WHV)-infected woodchuck as an animal model to test the efficacy and safety of GM-CSF on the therapy of chronic hepatitis B, woodchuck GM-CSF will be required due to the apparent species-specific activity of GM-CSF. The cDNA of woodchuck GM-CSF was cloned using reverse transcription-polymerase chain reaction (RT-PCR) with primers deriving from highly conserved regions of GM-CSF genes from other species. The deduced amino acids, including the signal peptide, is 138 in length and its identities to human, murine, canine and bovine GM-CSFs are 63, 49, 63, and 63% respectively. The genomic DNA of woodchuck GM-CSF was also cloned by PCR. Its organization is highly homologous to that of human and murine GM-CSF genes, consisting of four exons and three introns. Cloned woodchuck GM-CSF was expressed transiently in 293T cells. The recombinant protein expressed was found to stimulate the growth and differentiation of woodchuck bone marrow cells, indicating the protein expressed by the cloned gene is functional. These results pave the way for future studies on the potential role of GM-CSF for the treatment of chronic hepatitis B by using this animal model.

Blockade of alpha1-adrenoceptors and cardiac depressant effect by a newly synthetic antihypertensive drug, DL-017 of quinazoline derivative

The electromechanical effects of 3-[[4-(2-methoxy phenyl)piperazin-1-yl]methyl]-5-(methylthio)-2,3-dihydroimidazo[1,2-c]quinazoline (DL-017), a newly synthesized quinazoline-derived antihypertensive agent, on mammalian cardiac tissues were evaluated. In driven canine Purkinje fibers, DL-017 decreased twitch tension, the maximal rate of upstroke of the action potential (Vmax), and intracellular Na+ activity (a(i)Na) in a concentration-dependent manner. The action potential duration was decreased in canine Purkinje fibers but increased in guinea pig papillary muscles. In guinea pig ventricular papillary muscles, phenylephrine in the presence of 1 microM propranolol increased the twitch tension in a concentration-dependent manner. At 10 microM, phenylephrine significantly decreased a(i)Na and shortened the action potential duration. DL-017 at 0.01 microM inhibited these phenylephrine-induced effects and shifted the concentration-dependent curve to the right. In sinoatrial nodes, DL-017 inhibited pacemaker activity, involving decreases in the slope of diastolic depolarization and Vmax and an increase in a delay of repolarization. These results suggest that, in addition to blockade of alpha1-adrenoceptors and Na+ channels, DL-017 reduces cardiac excitability and contractility in association with inhibition of slow inward Ca2+ and outward K+ channels. Since two order higher concentrations are required, the contribution of DL-017 to cardiac depressant from blockade of ionic channels seems to be less important when this compound is clinically used as an antihypertensive drug.

Existence of hepatitis C virus in Culex quinquefasciatus after ingestion of infected blood: experimental approach to evaluating transmission by mosquitoes

We used PCR to detect hepatitis C virus (HCV) RNA among supernatants of ground Culex quinquefasciatus mosquitoes that (i) had been fed HCV-positive blood, (ii) had been intrathoracically inoculated with HCV-positive blood, or (iii) were from homes of hepatitis C patients. HCV RNA was detectable under all three conditions, but it did not replicate in mosquitoes and was not detectably transmitted during feeding.