Growth, nutrient removal, and lipid productivity promotion of Chlorella sorokiniana by phosphate solubilizing bacteria Bacillus megatherium in swine wastewater: Performances and mechanisms

Effects of a phosphorus-solubilizing bacteria (PSB) Bacillus megatherium on growth and lipid production of Chlorella sorokiniana were investigated in synthesized swine wastewater with dissolved inorganic phosphorus (DIP), insoluble inorganic phosphorus (IIP), and organic phosphorus (OP). The results showed that the PSB significantly promoted the algal growth in OP and IIP, by 1.10 and 1.78-fold, respectively. The algal lipid accumulation was also greatly triggered, respectively by 4.39, 1.68, and 1.38-fold in DIP, IIP, and OP. Moreover, compared with DIP, OP improved the oxidation stability of algal lipid by increasing the proportion of saturated fatty acids (43.8 % vs 27.9 %), while the PSB tended to adjust it to moderate ranges (30.2-41.6 %). Further, the transcriptome analysis verified the OP and/or PSB-induced up-regulated genes involving photosynthesis, lipid metabolism, signal transduction, etc. This study provided novel insights to enhance microalgae-based nutrient removal combined with biofuel production in practical wastewater, especially with complex forms of phosphorus.

Two new cytochalasins from the endophytic fungus Xylaria sp. GDGJ-77B

Two new open-chain cytochalasins, xylarchalasins A and B (1 and 2), together with six known analogues (3-8), were isolated from the endophytic fungus Xylaria sp. GDGJ-77B from the Chinese medicinal plant Sophora tonkinensis. Their structures were elucidated on the basis of comprehensive spectroscopic analysis. Compound 2 displayed moderate antibacterial activities against Bacillus subtilis and Escherichia coli with MIC values of 25 and 12.5 μg/mL, respectively.

Cycloaspeptide H, a cyclopentapeptide from the endophytic fungus Penicillium virgatum

One new cyclopentapeptide, cycloaspeptide H (1), featuring a serine residue, along with seven known compounds (2-8), was isolated from the endophytic fungus Penicillium virgatum GDGJ-227. The planar structure of 1 was elucidated by a comprehensive analysis of NMR and MS spectroscopic spectra, and the absolute configuration was determined by single-crystal X-ray diffraction (Cu Kα) analysis. Compounds 7 and 8 displayed antibacterial activities against Bacillus subtilis and Enterobacter aerogenes with MIC values ranging from 12.5 to 50 μg/mL.

Role of MEG3 in Cellular Physiology of Atherosclerosis

OBJECTIVE

To investigate the role of the lncRNA MEG3 (MEG3) in opposing the biochemical processes thought to be involved in the development of atherosclerosis (AS).

METHODS

Thirty patients with AS and thirty healthy control subjects were enrolled in this study. The expression of MEG3, miR-200b-3p and ABCA1 was analyzed by RT-qPCR in the individuals and the macrophages-derived foam cells. Lipid accumulation was detected by oil red O staining. Cholesterol efflux was measured by ELISA assay in the foam cells. Expression of miR-200b-3p was identified by sequencing. Targeting relationships were determined by dual luciferase assay between MEG3 and miR-200b-3p, miR-200b-3p and ABCA1.

RESULTS

In the patients with AS, MEG3 and ABCA1 expression were decreased and miR-200b-3p expression was upregulated. Foam cells transfected with an expression vector (pcDNA3.1) containing MEG3 (pcDNA3.1-MEG3) induced decrease of lipid accumulation and increase of cholesterol efflux compared to cells transfected with control plasmid alone. Foam cells transfected by pcDNA3.1-MEG3 also showed decreased miR-200b-3p and increased ABCA1 expression. Interestingly, co-expression of miR-200b-3p partially prevented these effects of MEG3 expression.

CONCLUSION

Expression of MEG3 is downregulated in the patients with AS and foam cells. Overexpressed MEG3 may act as an anti-atherosclerotic factor by reducing lipid accumulation and accelerating cholesterol efflux through the miR-200b-3p/ABCA1 axis.

Identification and Characterization of a New Regulator, TagR, for Environmental Stress Resistance Based on the DNA Methylome of Streptomyces roseosporus

DNA methylation is a defense that microorganisms use against extreme environmental stress, and improving resistance against environmental stress is essential for industrial actinomycetes. However, research on strain optimization utilizing DNA methylation for breakthroughs is rare. Based on DNA methylome analysis and KEGG pathway assignment in Streptomyces roseosporus, we discovered an environmental stress resistance regulator, TagR. A series of in vivo and in vitro experiments identified TagR as a negative regulator, and it is the first reported regulator of the wall teichoic acid (WTA) ABC transport system. Further study showed that TagR had a positive self-regulatory loop and m4C methylation in the promoter improved its expression. The ΔtagR mutant exhibited better hyperosmotic resistance and higher decanoic acid tolerance than the wild type, which led to a 100% increase in the yield of daptomycin. Moreover, enhancing the expression of the WTA transporter resulted in better osmotic stress resistance in Streptomyces lividans TK24, indicating the potential for wide application of the TagR-WTA transporter regulatory pathway. This research confirmed the feasibility and effectiveness of mining regulators of environmental stress resistance based on the DNA methylome, characterized the mechanism of TagR, and improved the resistance and daptomycin yield of strains. Furthermore, this research provides a new perspective on the optimization of industrial actinomycetes. IMPORTANCE This study established a novel strategy for screening regulators of environmental stress resistance based on the DNA methylome and discovered a new regulator, TagR. The TagR-WTA transporter regulatory pathway improved the resistance and antibiotic yield of strains and has the potential for wide application. Our research provides a new perspective on the optimization and reconstruction of industrial actinomycetes.

Inhibition of influenza A virus replication by a marine derived quinolone alkaloid targeting virus nucleoprotein

Owing to the emergence of drug resistance and high morbidity and mortality, the need for novel anti-influenza A virus (IAV) drugs with divergent targets is highly sought after. Herein, a novel quinolone alkaloid (QLA) derived from marine fungus was discovered with broad-spectrum anti-IAV activities with low toxicity. Distinct from current anti-IAV drugs, QLA may block virus replication and viral RNA (vRNA) export from the nucleus by targeting virus nucleoprotein (NP). QLA can block the binding of chromosome region maintenance 1 to nuclear export signal 3 of NP to inhibit the nuclear export of NP and vRNP. QLA may also affect vRNP assembly by interfering with the binding of NP to RNA rather than NP oligomerization. Arg305 and Phe488-Gly490 may be required for the interaction between QLA and NP, and the binding pocket around these amino acids may be a promising target for anti-IAV drugs. Importantly, oral administration of QLA can protect the mice against IAV-induced death and weight loss, superior to the effects of the clinical drug oseltamivir. In summary, the marine derived compound QLA has the potential to be developed into a novel anti-IAV agent targeting virus NP protein in the future.

Targeted isolation of antitubercular cycloheptapeptides and an unusual pyrroloindoline-containing new analog, asperpyrroindotide A, using LC-MS/MS-based molecular networking

Further insights on the secondary metabolites of a soft coral-derived fungus Aspergillus versicolor under the guidance of MS/MS-based molecular networking led to the isolation of seven known cycloheptapeptides, namely, asperversiamides A-C (1-3) and asperheptatides A-D (4-7) and an unusual pyrroloindoline-containing new cycloheptapeptide, asperpyrroindotide A (8). The structure of 8 was elucidated by comprehensive spectroscopic data analysis, and its absolute configuration was determined by advanced Marfey's method. The semisynthetic transformation of 1 into 8 was successfully achieved and the reaction conditions were optimized. Additionally, a series of new derivatives (10-19) of asperversiamide A (1) was semi-synthesized and their anti-tubercular activities were evaluated against Mycobacterium tuberculosis H37Ra. The preliminary structure-activity relationships revealed that the serine hydroxy groups and the tryptophan residue are important to the activity.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s42995-022-00157-8.

Improving the Yield and Quality of Daptomycin in Streptomyces roseosporus by Multilevel Metabolic Engineering

Daptomycin is a cyclic lipopeptide antibiotic with a significant antibacterial action against antibiotic-resistant Gram-positive bacteria. Despite numerous attempts to enhance daptomycin yield throughout the years, the production remains unsatisfactory. This study reports the application of multilevel metabolic engineering strategies in Streptomyces roseosporus to reconstruct high-quality daptomycin overproducing strain L2797-VHb, including precursor engineering (i.e., refactoring kynurenine pathway), regulatory pathway reconstruction (i.e., knocking out negative regulatory genes arpA and phaR), byproduct engineering (i.e., removing pigment), multicopy biosynthetic gene cluster (BGC), and fermentation process engineering (i.e., enhancing O₂ supply). The daptomycin titer of L2797-VHb arrived at 113 mg/l with 565% higher comparing the starting strain L2790 (17 mg/l) in shake flasks and was further increased to 786 mg/l in 15 L fermenter. This multilevel metabolic engineering method not only effectively increases daptomycin production, but can also be applied to enhance antibiotic production in other industrial strains.

Pneumothorax during retroperitoneal laparoscopic partial nephrectomy in a lupus nephritis patient: A case report

BACKGROUND

Downgrading target treatment and laparoscopic partial nephrectomy have become increasingly popular in patients with renal cell carcinomas. Rare as it is, pneumothorax is one of the most severe intraoperative complications which needs immediate recognition. On the other hand, as a rheumatological disease, lupus nephritis requires a long period of hormone therapy. Cases of pneumothorax in hormone-consuming renal cancer patients are even fewer.

CASE SUMMARY

A 39-year-old woman was admitted to our department to take a laparoscopic partial nephrectomy. The patient had a medical history of lupus nephritis and renal clear cell carcinoma with hormone and target treatment. Her blood oxygen saturation dropped to 92% during the operation, and pneumothorax was detected by ultrasound. O₂ inhalation and lung dilation were performed. Her vital signs were monitored closely throughout the operation. The operation was accomplished, and she regained consciousness smoothly. A postoperative bedside chest X-ray was conducted after she was transferred to the urosurgery ward, while no evidence of further pneumothorax or lib injury was observed.

CONCLUSION

Pneumothorax is a severe complication in laparoscopic or robotic-assisted laparoscopic operations, especially in retroperitoneal ones. It is easily neglected unless the injury of the diaphragm is found. Low insufflation pressure and shorter operation time are necessary for patients with a history of long-term hormone consumption or chronic immune system disease.

Serum Inflammatory Biomarkers Contribute to the Prognosis Prediction in High-Grade Glioma

Background

To evaluate the prognostic value of serum inflammatory biomarkers and develop a risk stratification model for high-grade glioma (HGG) patients based on clinical, laboratory, radiological, and pathological factors.

Materials and Methods

A retrospective study of 199 patients with HGG was conducted. Patients were divided into a training cohort (n = 120) and a validation cohort (n = 79). The effects of potential associated factors on the overall survival (OS) time were investigated and the benefits of serum inflammatory biomarkers in improving predictive performance was assessed. Univariable and multivariable Cox regression analyses, the least absolute shrinkage and selection operator (LASSO) regression analysis, and support vector machines (SVM) were used to select variables for the final nomogram model.

Results

After multivariable Cox, LASSO, and SVM analysis, in addition to 3 other clinico-pathologic factors, platelet-to-lymphocyte ratio (PLR) >144.4 (hazard ratio [HR], 2.05; 95% confidence interval [CI], 1.25–3.38; P = 0.005) were left for constructing the predictive model. The model with PLR exhibited a better predictive performance than that without them in both cohorts. The nomogram based on the model showed an excellent ability of discrimination in the entire cohort (C-index, 0.747; 95%CI, 0.706–0.788). The calibration curves showed good consistency between the predicted and observed survival probability.

Conclusion

Our study confirmed the prognostic value of serum inflammatory biomarkers including PLR and established a comprehensive scoring system for the OS prediction in HGG patients.

Structure modification, antialgal, antiplasmodial, and toxic evaluations of a series of new marine-derived 14-membered resorcylic acid lactone derivatives

Marine natural products play critical roles in the chemical defense of many marine organisms and are essential, reputable sources of successful drug leads. Sixty-seven 14-membered resorcylic acid lactone derivatives 3-27 and 30-71 of the natural product zeaenol (1) isolated from the marine-derived fungus Cochliobolus lunatus were semisynthesized by chlorination, acylation, esterification, and acetalization in one to three steps. The structures of these new derivatives were established by HRESIMS and NMR techniques. All the compounds (1-71) were evaluated for their antialgal and antiplasmodial activities. Among them, 14 compounds displayed antifouling activities against adhesion of the fouling diatoms. In particular, 9 and 34 exhibited strong and selective inhibitory effects against the diatoms Navicula laevissima and Navicula exigua (EC₅₀ = 6.67 and 8.55 μmol/L), respectively, which were similar in efficacy to those of the positive control SeaNine 211 (EC₅₀ = 2.90 and 9.74 μmol/L). More importantly, 38, 39, and 69-71 showed potent antiplasmodial activities against Plasmodium falciparum with IC₅₀ values ranging from 3.54 to 9.72 μmol/L. Very interestingly, the five antiplasmodial derivatives displayed non-toxicity in the cytotoxicity assays and the zebrafish embryos model, thus, representing potential promising antiplasmodial drug agents. The preliminary structure-activity relationships indicated that biphenyl substituent at C-2, acetonide at positions C-5' and C-6', and tri- or tetra-substituted of acyl groups increased the antiplasmodial activity. Therefore, combining evaluation of chemical ecology with pharmacological models will be implemented as a systematic strategy, not only for environmentally friendly antifoulants but also for structurally novel drugs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42995-021-00103-0.

[Comparison of early postoperative effects between anterior bladder and posterior bladder approaches in robotic assisted laparoscopic radical prostatectomy]

Objective: To examine the effect of robotic assisted laparoscopic radical prostatectomy with different approaches on early postoperative effects. Methods: Totally 44 patients (average age of 65.9 years, range: 46 to 81 years) underwent robotic assisted laparoscopic radical prostatectomy by a single operator at Department of Urology, Peking Union Medical Collage Hospital from March 2018 to March 2020 were retrospectively analyzed. The mean age was 65.9 years (range: 46 to 81 years), including 24 cases in the anterior bladder approach group (anterior approach group) and 20 cases in the posterior bladder approach group (posterior approach group). The preoperative clinical data, perioperative related data and postoperative urinary control recovery were compared between the two groups by t test, χ² test or Fisher exact test. Results: In terms of clinical data, there was no difference in age, prostate volume, preoperative prostate specific antigen and Gleason score(all P>0.05). There was no significant difference in operation time ((184±43) minutes vs. (193±42) minutes, t=-0.599, P=0.55), bleeding volume ((218±88) ml vs. (225±115) ml, t=-0.244, P=0.81), postoperative stage (T2/T3: 15/9 vs. 12/8, χ²=0.029, P=0.87) and positive rate of cutting edge (29.2% (7/24) vs. 30.0% (6/20), χ²=0.004, P=0.95). In terms of postoperative urinary control, patient rates who achieved urinary control immediately after extubation was significantly higher for the posterior approach group than the anterior approach group (30.0% (6/20) vs. 4.2% (1/24), P=0.04). There was no significant difference between two groups for those who achieved urinary control 3 months after operation (6 cases vs. 11 cases, P=0.06), 6 months after operation (20 cases vs. 19 cases, P=0.36) and those who achieved urinary control 12 months after operation (23 cases vs. 19 cases, P=1). Conclusion: For robotic assisted laparoscopic radical prostatectomy, the posterior approach does not prolong the operation time, does not increase the amount of bleeding, and improves the short-term postoperative urinary control.

17-Hydroxybrevianamide N and Its N1-Methyl Derivative, Quinazolinones from a Soft-Coral-Derived Aspergillus sp. Fungus: 13S Enantiomers as the True Natural Products

Under the guidance of MS/MS-based molecular networking and HPLC-UV, two new alkaloid racemates, (±)-17-hydroxybrevianamide N (1) and (±)-N1-methyl-17-hydroxybrevianamide N (2), featuring a rare o-hydroxyphenylalanine residue and an imide subunit, were isolated from a soft-coral-derived Aspergillus sp. fungus. The true natural products (+)-1 and (+)-2 were further monitored and obtained from the freshly prepared EtOAc extracts, while (-)-1 and (-)-2 are artifacts generated during extraction and purification processes. Simultaneously, the structures including absolute configurations of (+)-13S-1, (-)-13R-1, (+)-13S-2, and (-)-13R-2 were elucidated on the basis of comprehensive spectroscopic analysis, ECD calculations, and X-ray diffraction data. Interestingly, basic solution promotes the racemization of (+)-1 and (-)-1, whereas acidic solution suppresses the transformation. The current research was concerned with the true natural products and their artifacts, providing critical insight into the isolation and identification of natural products.

Targeted Isolation of Asperheptatides from a Coral-Derived Fungus Using LC-MS/MS-Based Molecular Networking and Antitubercular Activities of Modified Cinnamate Derivatives

Under the guidance of MS/MS-based molecular networking, four new cycloheptapeptides, namely, asperheptatides A-D (1-4), were isolated together with three known analogues, asperversiamide A-C (5-7), from the coral-derived fungus Aspergillus versicolor. The planar structures of the two major compounds, asperheptatides A and B (1 and 2), were determined by comprehensive spectroscopic data analysis. The absolute configurations of the amino acid residues were determined by advanced Marfey's method. The two structurally related trace metabolites, asperheptatides C and D (3 and 4), were characterized by ESI-MS/MS fragmentation methods. A series of new derivatives (8-26) of asperversiamide A (5) were semisynthesized. The antitubercular activities of 1, 2, and 5-26 against Mycobacterium tuberculosis H37Ra were also evaluated. Compounds 9, 13, 23, and 24 showed moderate activities with MIC values of 12.5 μM, representing a potential new class of antitubercular agents.

Structure-Activity Relationships and Potent Cytotoxic Activities of Terphenyllin Derivatives from a Small Compound Library

A small library of 120 compounds was established with seventy new alkylated derivatives of the natural product terphenyllin, together with 45 previous reported derivatives and four natural p-terphenyl analogs. The 70 new derivatives were semi-synthesized and evaluated for cytotoxic activities against four cancer cell lines. Interestingly, 2',4''-diethoxyterphenyllin, 2',4,4''-triisopropoxyterphenyllin, and 2',4''-bis(cyclopentyloxy)terphenyllin showed potent activities with IC₅₀ values in a range from 0.13 to 5.51 μM, which were similar to those of the positive control, adriamycin. The preliminary structure-activity relationships indicated that the introduction of alkyl substituents including ethyl, allyl, propargyl, isopropyl, bromopropyl, isopentenyl, cyclopropylmethyl, and cyclopentylmethyl are important for improving the cytotoxicity.

Cochliomycin G, a 14-membered resorcylic acid lactone from a marine-derived fungus Cochliobolus lunatus

Cochliomycin G (1), a new 14-membered resorcylic acid lactone, together with six known analogues (2-7), was isolated from the culture broth of a marine-derived fungus Cochliobolus lunatus. The planar structure of 1 was established by extensive NMR spectroscopy, and the absolute configuration was elucidated by the combination of empirical rules, CD data, and ¹³C chemical shift calculations. Compound 1 exhibited potent antifouling activity against Chlorella vulgaris, Chaetoceros socialis, and Navicula exigua, with EC₅₀ values of 1.09, 0.92, and 0.61 μg/mL, respectively.

Growth promotion and disease resistance induced in Anthurium colonized by the beneficial root endophyte Piriformospora indica

BACKGROUND

Anthurium andraeanum, an important ornamental flower, has to go through a growth-delaying period after transfer from tissue culture to soil, which requires time and extra costs. Furthermore, during this period, the plantlets are highly susceptible to bacterial infections, which results in impaired development and severe losses. Here, we aimed to address whether application of the endophytic fungus, Piriformospora indica protects the A. andraeanum root system during the critical propagation period, and whether P. indica reduce the mortality rate by stimulating the host's resistance against diseases.

RESULTS

We demonstrate that P. indica shortens the recovery period of Anthurium, promotes growth and confers disease resistance. The beneficial effect of P. indica results in faster elongation of Anthurium roots early in the interaction. P. indica-colonized plants absorb more phosphorus and exhibit higher photosynthesis rates than uncolonized control plants. Moreover, higher activities of stress-related enzymes, of jasmonic acid levels and mRNA levels of jasmonic acid-responsive genes suggest that the fungus prepares the plant to respond more efficiently to potentially upcoming threats, including bacterial wilt.

CONCLUSION

These results suggest that P. indica is a helpful symbiont for promoting Anthurium rooting and development. All our evidences are sufficient to support the disease resistance conferred by P. indica through the plant-fungal symbiosis. Furthermore, it implicates that P. indica has strong potential as bio-fertilizer for utilization in ornamental plant cultivation.

[Surgery treatment of ectopic adrenocorticotrophic hormone syndrome]

OBJECTIVE

To investigation the diagnosis and treatment of ectopic adrenocorticotrophic hormone (ACTH) syndrome.

METHODS

The clinical characters of 57 cases of ecotopic ACTH syndrome from Jan. 1996 to Dec. 2016 were collected and analyzed. The 57 cases included 32 males and 25 females. The age ranged from 11 to 68 years (average 32 years). ACTH levels significantly increased from 16.5 to 365.6 pmol/L, with average 77.6 pmol/L (normal range <10.1 pmol/L). The pituitary MRI did not found lesions. The CT showed that their bilateral adrenal glands diffused small nodular changes or nodular hyperplasia. The 57 cases were divided into 3 groups according to different treatment options. In the study, 25 ectopic ACTH syndrome cases (44%) were group A, without identified source of ectopic hormone, were treated with bilateral or unilateral adrenalectomy due to the severity of the disease and difficulty of operation. Group B was composed of 16 cases (28%) diagnosed as ectopic ACTH syndrome by finding ectopic ACTH tumors and surgical resection. Group C included 16 cases (28%) with nonsurgical therapy. Different treatment results and prognosis were analyzed.

RESULTS

In the study, 40 cases of the 57 had been followed up for 6 months to 10 years. In group A, of the 25 cases with bilateral or unilateral adrenalectomy, 4 died of diabetes and severe pulmonary infection, 18 survived, and 3 were lost to the follow-up, and the survival rate was 81% (18/22). In group B, of the 16 cases with radical tumor resection, 5 died of tumor recurrence 0.5-6.0 years after operation, 3 survived, and 8 were lost to the follow-up, and the survival rate was 37.5% (3/8). In group C, of the 16 non-operation patients, 4 with radiotherapy and chemotherapy died of metastases, diabetes or pulmonary infection, 6 with chemotherapy died of pulmonary infection within 1 year and the others were lost to the follow-up, and the survival rate was 0.

CONCLUSION

Ectopic ACTH syndrome is difficult to treat. Adrenalectomy is effective for the management of ectopic ACTH syndrome, especially for those patients with severe Cushing's syndrome, but the primary tumor can not be located.

Xylapeptide A, an Antibacterial Cyclopentapeptide with an Uncommon L-Pipecolinic Acid Moiety from the Associated Fungus Xylaria sp. (GDG-102)

Two new cyclopentapeptides, xylapeptide A (1) with an uncommon L-pipecolinic acid moiety, and xylapeptide B (2) having a common L-proline residue were identified from an associated fungus Xylaria sp. isolated from the Chinese medicinal plant Sophora tonkinensis. Their planar structures were elucidated by a comprehensive analysis of NMR and MS spectroscopic spectra. The absolute configurations were determined by Marfey's method and single-crystal X-ray diffraction (Cu Kα) analysis. Xylapeptide A (1) is the first example of cyclopentapeptide with L-Pip of terrestrial origin and showed strong antibacterial activity against Bacillus subtilis and B. cereus with MIC value of 12.5 μg/mL.

Nigrodiquinone A, a Hydroanthraquinone Dimer Containing a Rare C-9-C-7' Linkage from a Zoanthid-Derived Nigrospora sp. Fungus

One new hydroanthraquinone dimer with a rare C-9–C-7′ linkage, nigrodiquinone A (1), and four known anthraquinone monomers 2–5, were isolated from a fungus Nigrospora sp. obtained from the zoanthid Palythoa haddoni collected in the South China Sea. The structure of 1 was established through extensive NMR spectroscopy, and the absolute configuration was elucidated by comparing computed electronic circular dichroism (ECD) and optical rotations (OR) with experimental results. All the compounds were evaluated for antiviral activity, and 1 was also evaluated for antibacterial activity. Compound 4 displayed mild antiviral activity against coxsackie virus (Cox-B3) with the IC₅₀ value of 93.7 μM, and 5 showed an IC₅₀ value of 74.0 μM against respiratory syncytial virus (RSV).

Rice G-protein subunits qPE9-1 and RGB1 play distinct roles in abscisic acid responses and drought adaptation

Heterotrimeric GTP-binding protein (G-protein)-mediated abscisic acid (ABA) and drought-stress responses have been documented in numerous plant species. However, our understanding of the function of rice G-protein subunits in ABA signalling and drought tolerance is limited. In this study, the function of G-protein subunits in ABA response and drought resistance in rice plants was explored. It was found that the transcription level of qPE9-1 (rice Gγ subunit) gradually decreased with increasing ABA concentration and the lack of qPE9-1 showed an enhanced drought tolerance in rice plants. In contrast, mRNA levels of RGB1 (rice Gβ subunit) were significantly upregulated by ABA treatment and the lack of RGB1 led to reduced drought tolerance. Furthermore, the results suggested that qPE9-1 negatively regulates the ABA response by suppressing the expression of key transcription factors involved in ABA and stress responses, while RGB1 positively regulates ABA biosynthesis by upregulating NCED gene expression under both normal and drought stress conditions. Taken together, it is proposed that RGB1 is a positive regulator of the ABA response and drought adaption in rice plants, whereas qPE9-1 is modulated by RGB1 and functions as a negative regulator in the ABA-dependent drought-stress responses.

Efficiency enhancement of organic solar cells using peroxo-polytitanic acid coated silver nanowires as transparent electrodes

Silver nanowires and peroxo-polytitanic acid gel combined with TiO_x used as conducting electrodes for organic solar cell application.

Effects of azithromycin on Pseudomonas aeruginosa isolates from catheter-associated urinary tract infection

Pseudomonas aeruginosa is a common pathogenic bacterium in urinary tract infections (UTIs), particularly catheter-associated UTIs. The aim of this study was to investigate the effect of azithromycin (AZM) on P. aeruginosa isolated from UTIs. Isolates were identified by biochemical assays and the Vitek system. Antimicrobial susceptibility was determined using the disk diffusion assay. Biofilm formation and adhesion were assayed using a crystal violet staining method. The swimming motility was assayed on agar plates. The elastase activity and rhamnolipid production were determined by the elastin-Congo red method and orcinol reaction, respectively. A total of 32 bacterial isolates were collected from 159 urinary catheters and eight of them were P. aeruginosa isolates. The results showed that the P. aeruginosa isolates had stronger biofilm formation capability and the biofilms were thicker than those of P. aeruginosa PAO1. AZM inhibited biofilm formation and adhesion on urinary catheters, and also decreased swimming motility and the production of virulence factors. The results of this study indicated that AZM is potentially a good choice for use in the treatment of UTIs.

HDAC6: physiological function and its selective inhibitors for cancer treatment

Acetylation and deacetylation of histones are important in regulating gene expression and play a key role in modification of gene transcription. Specific HDACs isoforms can be regarded as a target for cancer therapy avoiding side-effects, HDAC6 with a unique physiological function and structure has become a hot issue recently. The unique isoform HDAC6 is involved in tumorigenesis, development and metastasis through tubulin, HSP90, invasin and ubiquitin-protein. Here we review the structure elements, biological function, and recent selective inhibitors of HDAC6, and study the structure-activity and structure-selectivity relationship.

In vitro estimation of exposure of Hong Kong residents to mercury and methylmercury via consumption of market fishes

In order to evaluate effects of exposure to mercury (tHg) and methylmercury (MeHg) of Hong Kong residents via consumption of fish, total and bioaccessible concentrations of tHg and MeHg were measured in 10 freshwater and 10 marine fishes collected from markets in Hong Kong. Concentrations of tHg and MeHg in fishes ranged from 27.2 to 311ngg(-1) (median 88.9ngg(-1)) and ND to 116ngg(-1) (median 45.0ngg(-1)), respectively. Concentrations of MeHg in marine fishes (64.4±28.5ngg(-1)) were significantly greater than those in freshwater fishes (40.3±26.0ngg(-1)). Bioaccessibility tHg and MeHg was predicted for edible flesh of twenty fishes by use of an in vitro gastrointestinal assay. Bioaccessibilities of tHg and MeHg ranged from 21.4 to 51.7% (mean 37.4%) and 19.5 to 59.2% (mean 43.7%), respectively. Based on total concentrations, diets of 36% of adults and 51% of children exceeded the reference dose (RfD, 100ngkg(-1)bodymass(bm)d(-1)) for MeHg, but when bioaccessibility was considered, consumption of local market fish would not result in an EDIbio exceeded the RfD of MeHg for Hong Kong adults. These contradictory results suggested that risk assessments based on total concentrations would overestimate exposure because not all of contaminants consumed are bioaccessible. Furthermore, 9% of children had EDIbio for MeHg that exceeded the RfD, which suggests that more attention should be paid to consumption of local fish on health and development of children in Hong Kong.

[Investigation of subjective well-being and influence factors among residents living in old districts in Wuhan, China]

OBJECTIVE

To investigate the subjective well-being and its influence factors among residents living in old districts in Wuhan.

METHODS

In June, 2011, a total of 500 residents living in Shanghai Street in Wuhan were recruited as subjects for this study by two-stage stratified random sampling method. The information of demographic features, health status, spare time, family status, interpersonal relationship and social environment were collected by self-made questionnaires naming "survey of satisfaction of residents living in old districts". The results were analyzed by single-factor and multi-factors analysis method.

RESULTS

In this study, 448 samples of questionnaire were answered qualified (89.6%, 448/500). The subjects aged (51.3 ± 16.1) years old. The single-factor analysis showed that male and female influence the subjective happiness got 5.43 ± 1.66, 5.77 ± 1.65 (U = -2.32, P < 0.05);the age of 0 - 45, 46 - 59, 60 and above group got 5.12 ± 1.68, 5.47 ± 1.81, 6.29 ± 1.23, respectively (H = 43.07, P < 0.01); the unmarried, married, divorced, loss of spouse and remarriage groups got 5.18 ± 1.94, 5.74 ± 1.54, 4.00 ± 2.04, 5.68 ± 1.91, 6.63 ± 0.92, respectively (H = 17.41, P < 0.01); education background were primary school and blow, junior middle school, senior high school, bachelor degree, master degree and above got 6.30 ± 1.42, 5.55 ± 1.82, 5.90 ± 1.46, 5.07 ± 1.74, 4.75 ± 2.22 (H = 26.99, P < 0.01); monthly household income was ¥0 - 2000, ¥2001 - 4000, ¥4001 - 8000, ¥8001 - 10 000, ¥10 000 and above got 5.34 ± 1.87, 5.68 ± 1.53, 6.20 ± 1.07, 7.33 ± 0.58, 6.00 ± 0.00, respectively (H = 13.85, P < 0.01). The subjective satisfaction of social environment ranked from high to low were: city public security (56.0%, 248/448), traffic environment (44.9%, 199/448), community environment (14.9%, 66/448), housing conditions (13.8%, 61/448) and medical environment (8.2%, 36/448). Multiple regression model suggested that the determinant coefficient was 0.53(P < 0.01), with a good degree of fitting. The model showed that the factors influencing the residents' happiness were ranked: social environment (β' = 0.34), family status (β' = 0.32), health status (β' = 0.21), education background (β'(0-6) school year = 0.00, β'(7-9) school year = -0.12, β'(9-12) school year = 0.04, β'(>12) school year = -0.14), monthly household income (β' = 0.07) and marital status (β'(unmarried) = 0.00, β'(married) = 0.03, β'(divorced) = -0.03, β'(widowed) = 0.01, β'(remarried) = 0.02).

CONCLUSION

The factors that social environment, family status, health status, education background, monthly household income and marital status could influence the subjective happiness of residents living in old districts in Wuhan. A perfect social security system could improve the subjective happiness of residents in old districts in Wuhan.

A new boronic acid-based fluorescent sensor for L-dihydroxyphenylalanine

Catecholamines, such as dopamine and L-dihydroxyphenylalanine (L-DOPA), are associated with different physiological functions and diseases. In our recent studies, a novel water-soluble boronic acid compound 3c was identified as a selective fluorescent sensor for L-DOPA. This compound not only has the ability to interact with dopamine and catechol, but also has no fluorescence intensity change for L-DOPA precursors in vivo, such as L-tyrosine.

Modulation of anti-oxidation ability by proanthocyanidins during germination of Arabidopsis thaliana seeds

Proanthocyanidins (PAs) as the end products of flavonoid biosynthetic pathway mainly accumulate in seed coat but their biological function is largely unknown. We studied the anti-oxidation ability in seed coat and germination changes under externally applied oxidative stresses in PAs-deficient mutants of Arabidopsis. Germination of PAs-deficient mutant seeds was faster than that of wild-type under low or no oxidative stress, suggesting a PAs-induced inhibition of germination. When the applied oxidative stress was high, germination of PAs-deficient mutants was lower than that of wild-type, suggesting a loss of PAs-related anti-oxidation ability in the mutants. Using ABA signaling mutants, our studies demonstrated that both ABA signaling pathway and PAs were important for the response to serve oxidative stress during seed germination. However, the discrepancy of the response between abi mutants and PAs mutants to oxidative stress suggests that ABA signaling pathway may not play a major role in PAs' action in alleviating oxidative stress. Under low or no oxidative stress, germination was mainly determined by the ABA content in seed and the PAs-deficient mutant seeds germinated faster due to their lower ABA content than wild-type. However, oxidative injury inhibited germination when PAs-deficient seeds germinated under high oxidative stress. Wild-type exhibited higher germination under the high oxidative stress due to the PAs' anti-oxidation ability. Oxidative stress applied externally led to changes in endogenous PAs contents that coincided with the expression changes of PAs biogenesis genes. PAs modulated the activities of some key enzymes that controlled the levels of reactive oxygen species and the anti-oxidation capacity during the seed germination. This work suggests that PAs contribute to the adaptive mechanism that helps germination under environmental stresses by playing dual roles in both germination control and anti-oxidation reaction.

Expression, purification, and S-nitrosylation of recombinant histone deacetylase 8 in Escherichia coli

Histone deacetylase (HDAC) 8 is a zinc ion dependent enzyme involved in removing the acetyl group from the core histones and other proteins which belong to Class I HDACs. It was reported that nitric oxide (NO) is a key regulator of HDAC function and S-nitrosylation of HDAC2 induces chromatin remodelling in neurons. This work reports the successful recombinant expression of human HDAC8 in Escherichia coli with two plasmids and the purification and S-nitrosylation in vitro. It was found that HDAC8 can be S-nitrosylated by the NO donor S-nitrosoglutathione (GSNO) in vitro, and the activity of HDAC8 was significantly inhibited when incubated with GSNO and S-nitrosocysteine in a time- and dosage-dependent manner, but sodium nitroprusside (SNP), and dithiothreitol cannot reverse this inhibition. These observations support and extend the concept that NO may regulate HDAC8 function by S-nitrosylation.

[Clinical features of urological malignancies with paraneoplastic syndromes]

OBJECTIVE

To investigate the clinical features of paraneoplastic syndromes (PNS) in patients with renal, prostate and bladder cancer and conduct a brief prognostic analysis.

METHODS

From 2008 to 2010, 464 patients of renal cell carcinoma (RCC) confirmed by operation and pathology were reviewed retrospectively. And 562 cases of patients with prostate cancer and 647 with bladder cancer from 2005 to 2010 were also analyzed respectively.

RESULTS

Among all cases, 156(33.6%)patients were diagnosed with PNS manifesting with anemia, hypertension, fever, polycythemia, Stauffer's syndrome, fatigue, weight loss, anorexia, leukocytosis and hypercalcemia, etc. Two prostate cancer patients had the elevated levels of calcemia and blood glucose respectively. However, no specific clinical presentation in bladder cancer was found to be associated with PNS in this study.

CONCLUSION

RCC is the most frequent urological malignancy with PNS. But prostate cancer with PNS is very uncommon and bladder cancer is extremely rare. Most paraneoplastic signs predicate a poor prognosis for the patients.

Lambda-carrageenan oligosaccharides elicit reactive oxygen species production resulting in mitochondrial-dependent apoptosis in human umbilical vein endothelial cells

Previous studies have shown that highly sulfated lambda-carrageenan oligosaccharides (lambda-CO) possess an anti-angiogenetic effect, while high concentrations of lambda-CO present a cytotoxic effect towards human umbilical vein endothelial cells (HUVECs). The aim of this study was to explore the underlying mechanism of lambda-CO on inhibiting cell proliferation. lambda-CO elicited reactive oxygen species (ROS) production with concentrations at 0.8 and 1 mg/ml, and this event was accompanied by the increase of early apoptotic cells, nuclear morphology changes and cell cycle arrest at the S and G2/M phases. However, prevention of oxidative stress by N-acetyl-L-cysteine (NAC) could abolish the effect of lambda-CO on these events. Yet, lambda-CO induced a depolarization of mitochondrial transmembrane potential. At 0.8 mg/ml, lambda-CO induced up-regulation of p53 and Bax, down-regulation of Bcl-2 and activation of caspase-9 and -3. These results suggest that exposure to a high concentration of lambda-CO activates the mitochondrial-mediated apoptotic pathway and cell cycle arrest by generation of ROS.

Design, synthesis, and primary activity evaluation of pyrrolidine derivatives as matrix metalloproteinase inhibitors

A series of novel pyrrolidine derivatives was designed, synthesized, and assayed to determine the derivatives' activity against matrix metalloproteinase-2 (MMP-2) and aminopeptidase N (APN)/CD13. Preliminary biological tests showed that most compounds inhibit MMP-2 in a highly selective manner compared to APN. Compounds 9d, 9e, and 9g had better inhibitory activity than LY52 and could be used as lead compounds in the future.

A microplate-based screening assay for neuraminidase inhibitors

Neuraminidase (NA) represents a highly promising new target for drug development in influenza virus genes. Rapid screening of enzyme inhibitors is a key method for the identification of leading compounds. In order to speed up the screening for enzyme inhibitors of natural and synthetic origin, effective and fast assays are needed. 2'-(4-Methylumbelliferyl)-α-D-N-acetylneuraminic acid (4-MUNANA) was selected as substrate for development of a microplate-based assay. The enzymatic reaction conditions were optimized as follows: in a 100 μL reaction mixture, the final concentrations were 32.5 mM sodium acetate (pH 3.5), 20 μM 4-MUNANA, 0.005% (w/v) bovine serum albumin, and 0.42 μg/mL NA. In the study, the doseresponse relationship of oseltamivir carboxylate to NA activity was observed. In addition, an overall Z' value of 0.8 proved the systems robustness and potential for screening. The assay system developed will be a valuable tool to discover new structures for the therapeutic inhibition of NA used to treat Influenza.

Direct effects of fascaplysin on human umbilical vein endothelial cells attributing the anti-angiogenesis activity

Novel anti-angiogenesis activity of fascaplysin via VEGF blockage was recently revealed by our previous study in addition to the reported cyclin-dependent kinase 4 (CDK4) selective inhibition. To uncover more details of this pharmacologically prospective property, this study further investigated whether fascaplysin had direct anti-proliferation effects on human umbilical vein endothelial cells (HUVEC), which might be contributing to anti-angiogenesis. The results showed that G1 cell cycle arrest was induced by 2.6 μM fascaplysin in a time-dependent manner, and exhibited more sensitive than hepatocarcinoma cells BeL-7402 and Hela cells. Approximately 56.09 ± 2.63% of the cells were arrested at the G1 phase after 24h, and 64.94 ± 2.07% after 36 h, comparing to the 22.82 ± 1.2% in methanol treated cells. Apoptosis of HUVEC cells was induced by 1.3 μM fascaplysin and indicated by the sub-G1, Hoechst staining, terminal deoxynucleotidyl transferase dUTP-mediated nicked end labeling (TUNEL) assay, and annexin-V and propidium (PI) label. This apoptosis response was further confirmed by the detection of active caspase-3 and by western blotting using antibodies against Bax, Bcl-2, procaspase-8, and Bid, indicating that apoptosis in HUVEC cells may involve a mitochondria pathway, by the demonstration of an increase in the Bax/Bcl-2 ratio. Together, our results suggest that the anti-angiogenesis activity of fascaplysin is through the direct effects of cell cycle arrest and apoptosis on HUVEC.

[Anti-proliferation of human cervical cancer HeLa cell line by fascaplysin through apoptosis induction]

This study is to investigate the effect of fascaplysin on human cervical cancer cells (HeLa) in order to provide insights into the mechanisms of growth suppression involved in fascaplysin-mediated apoptosis. Cytotoxic activity of fascaplysin on HeLa cells was determined using MTT assay, cell cycle analysis, and apoptosis (Annexin V-FITC and PI double staining) studies. The role of the molecules in cell cycle regulation and apoptosis was analyzed by Western blotting and flow cytometry. Fascaplysin markedly inhibited HeLa cells proliferation in a dose-dependent manner, however, did not provoke G1 phase arrest in HeLa cells with downregulation of CDK4, cyclin D1 and CDK4-specific Ser795 pRb phosphorylation. Furthermore, fascaplysin induced significantly apoptosis evidenced by sub-G1 peak and Annexin V-FITC and PI double staining. The molecular mechanism of fascaplysin-induced apoptosis was characterized with the activation of caspase-3, -8, and -9, truncation of Bid, release of cytochrome c into cytosol, and down-regulation of Bcl-2 level. Fascaplysin exhibits anti-proliferation effect towards human cervical cancer HeLa cells through induction of apoptosis via extrinsic death pathway and mitochondrial pathway, but not arresting cell cycle progression at G1 phase. All together, these data sustain our contention that fascaplysin has anticancer properties and merits further investigation as a potential therapeutic agent.

QSAR studies of histone deacetylase (HDAC) inhibitors by CoMFA, CoMSIA, and molecular docking

In order to develop highly potent antitumor agents, three-dimensional quantitative structure-activity relationship (3-D QSAR) studies were conducted using a series of thienyl-based hydroxamic acids. Comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methods were applied to provide the structural information for further chemical modification and optimization. ClogP was applied as an additional descriptor in the CoMFA analysis to study the effects of lipophilic parameters on the activity of these compounds, and it did improve the statistical significance of the model. Two molecules were designed based on the 3-D QSAR analysis, their activity values were predicted by the generated model, and their binding mode was elucidated by a docking approach compared to molecules in the dataset.

The main functions and structural modifications of tripeptide N-formyl-methionyl-leucyl-phenylalanine (fMLP) as a chemotactic factor

Gram negative bacteria-derived and synthetic N-formyl peptides play a key role in host defense as chemotactic factors for phagocytic leukocytes. The first compound to be identified was N-formylmethionyl-leucyl-phenylalanine (fMLP) which contains highly potent leukocyte chemoattractant. Natural fMLP was subsequently purified and identified in supernatants of gram negative bacteria. Recently, much more attention has been focused on the human formyl peptide receptor (FPR) and its variant formyl peptide receptor-like 1 (FPRL1) and formyl peptide receptor-like 2 (FPRL2). Chemotactic factors such as fMLP interact with their specific cell surface receptors, which results in multiple biological responses through a G protein-coupled signal pathway. In this review, the functions and structural modifications of fMLP are discussed in view of future drug development.

Novel N-hydroxybenzamide histone deacetylase inhibitors as potential anti-cancer agents

Histone deacetylases (HDACs) are a class of Zn(2+) dependent metalloproteases that play an important role in tumorigenesis. Inhibition of HDACs may be a potential strategy for cancer therapy. This study designed and synthesized a series of novel N-hydroxybenzamide histone deacetylase inhibitors based on the structural features of suberoylanilide hydroxamic acid (SAHA), the first HDAC inhibitor that came to market. Preliminary biological evaluation in vitro found that most of the inhibitors had satisfactory inhibitory activity (IC(50) =1-17 μM) against HDACs and HCT116 tumor cells.

[Proliferation inhibition of lambda-carrageenan oligosaccharides on HUVEC and expression of apoptotic relevant genes]

To study the anti-proliferation effect of lambda-carrageenan oligosaccharides (lambda-CO) on human umbilical vein endothelial cells (HUVECs) and expression of apoptotic relevant genes, the influence of lambda-CO on HUVECs proliferation was measured by MTT assay; apoptotic rate, cell cycle distribution and the level of active caspase-3 of HUVECs were analyzed using flow cytometry; the mRNA level of apoptosis related genes was determined by RT-PCR. At a high concentration of 1 mg x mL(-1), lambda-CO significantly inhibited the endothelial cell proliferation. Annexin-V FITC/PI double stain assay showed that when treated with 0, 0.8, 1 mg x mL(-1) of lambda-CO for 24 h, cell apoptotic rates were (1.67 +/- 1.6)%, (11.48 +/- 2.4)% and (13.81 +/- 2.2)%, respectively, when treated for 48 h, cell apoptotic rates were (2.02 +/- 2.3)%, (13.84 +/- 1.9)% and (38.72 +/- 2.5)%, respectively, cell cycle assay showed the decrease of cells in G0/G1 phase, and increase in S phase. Furthermore, we observed the level of active caspase-3 increased in a dose-dependent manner at 24 th and 48 th. RT-PCR results indicated that mRNA of TNFalpha, p53, caspase-8 and caspase-3 in cells increased after treated with lambda-CO. lambda-CO induce apoptosis of HUVECs in a dose-dependent way and arrests cells at S phase, which mainly due to the up-regulation of apoptotic genes such as TNFalpha, p53, caspase-8, caspase-3 and increase the level of active caspase-3.

3D-QSAR study with pharmacophore-based molecular alignment of hydroxamic acid-related phosphinates that are aminopeptidase N inhibitors

3D-QSAR models for a series of aminopeptidase N inhibitors were developed based on comparative molecular field analysis (CoMFA) and comparative molecular similarity analysis (CoMSIA).GALAHAD, a pharmacophore generation module involving a genetic algorithm, was used to generate the pharmacophore model of the series of inhibitors. Molecules both in the training set and test set were aligned to the pharmacophore model. Values for the CoMFA model were r(2) = 0.992, q(2) = 0.586, SEE = 0.111, and F (8, 10) = 191.263. Values for the CoMSIA model were r(2) = 0.990, q(2) = 0.776, SEE = 0.123, and F (7, 11) = 156.68. This model can help not only in improving current understanding of enzyme-ligand interactions but also in predicting the activity of derivatives and designing new compounds with better potency.

[Subclinical Cushing's syndrome:analysis of diagnosis and surgical effect]

OBJECTIVE

To improve the diagnostic and therapeutic ability on subclinical Cushing's syndrome.

METHODS

Retrospective analysis for the clinical data of 24 cases of subclinical Cushing's syndrome, the clinical and biological characters pre and post operation were compared.

RESULTS

None of the 24 cases of subclinical Cushing's syndrome had the classic symptoms and signs of Cushing's syndrome. The common symptoms of these patients were hypertension in 17 cases, diabetes mellitus in 11 cases, hyperlipidemia in 9 cases, high plasma cortisol value in 13 cases and high 24 h UFC value in 9 cases. None of patients did respond to low dose dexamethasone suppression test, but 16 cases of them did not respond to high dose dexamethasone suppression test. All the cases were found adrenal tumors by CT scan, 10 cases in left adrenal and 14 cases in right adrenal. All the patients underwent retroperitoneal laparoscopic operation and were pathologic diagnosed to adrenal adenomas. During follow-up, the symptoms of 20 cases (83.3%) were cured after surgery, and hormone supplement was required in 8 cases.

CONCLUSIONS

Subclinical Cushing's syndrome may be incidentally detected on clinical manifestations, laboratory findings and imaging examinations. CT scan, assays of plasma cortisol, urinary free cortisol and dexamethasone suppression test are most useful in the diagnosis. The potential benefit of surgery should be considered in those who have a definite diagnosis of subclinical Cushing's syndrome. Hormone supplement is required in some patients. It is safe and practical to perform retroperitoneal laparoscopic surgery on the patients with subclinical Cushing's syndrome.

[The significance of Ki-67 antigen expression in the distinction between benign and malignant pheochromocytomas]

OBJECTIVES

To investigate the expression of Ki-67 antigen in benign and malignant pheochromocytomas, and to evaluate whether the expression of Ki-67 antigen could serve as a diagnostic marker for predicting the biological behaviour of these tumors.

METHODS

Ki-67 antigen were detected by immunohistochemical technique and image analysis in 57 cases of clinically documented benign and malignant pheochromocytomas were analyzed. Aside from histological study, Ki-67 immunohistochemistry studies were performed to get the Ki-67 index. Statistical analysis was performed between these groups.

RESULTS

Ki-67 index was low in benign pheochromocytomas (average 0.98%), and high in malignant pheochromocytomas (average 3.78%). There was statistically significant difference in expressions of Ki-67 antigen between benign and malignant pheochromocytomas. The Ki-67 index of 2 cases in benign pheochromocytomas (5.1%, 2/39) and 10 cases in malignant pheochromocytomas (55.6%, 10/18) was higher than 3%. The accuracy, sensitivity, specificity, positive predictive value and negative predictive value of Ki-67 index higher than 3% to diagnosis malignant pheochromocytomas was 82.5%, 55.6%, 94.9%, 83.3% and 82.2%. The follow-ups indicated the survival rate of patients with higher Ki-67 index was lower than those with lower Ki-67 index.

CONCLUSIONS

Ki-67 may serve as a useful marker of the biological behavior of tumors, and can provide useful information for prognosis of tumor patients. Immunohistochemical assessment of Ki-67 antigen can be useful in the differential diagnosis of malignant from benign pheochromocytomas. Ki-67 index (> 3%) is a useful marker for distinguishing benign from malignant tumors or for predicting the malignant potential of pheochromocytomas.

China's efforts to shed its title of "Leader in liver disease"

According to Xinhua News, Chen Zhu, China's Minister of Health, mentioned at the 2007 Annual Conference of the China Association for Science and Technology (CAST) that an action plan for the diagnosis and treatment of hepatitis B could control hepatitis B virus (HBV) infection to below 1% by 2050. This plan is one of the Health Ministry's goals for middle-long-term development planning in medical science and technology that China is endeavoring to reach (http://hbv.39.net/079/18/127612.html, available as of September 18, 2007). The Ministry's strategy involves a series of action plans for other areas like HIV, tuberculosis, malignant tumor control, and mental health, but chronic HBV therapy is more important and more urgent. HBV infection is a leading cause of illness and death in China. Approximately 60% of the population has a history of HBV infection, and 9.8% of persons in China are chronically infected with HBV and at risk for premature death from liver disease. Each year, an estimated 263,000 persons in China die from HBV-related liver cancer or cirrhosis, accounting for 37%~50% of HBV-related deaths worldwide (Available as a report from the Centers for Disease Control and Prevention (CDC), 2007;56:441-445. http://www.cdc.gov/mmwr/previe / mmwrhtml/mm5618a2.htm, May 11, 2007). Besides China, HBV is highly prevalent in approximately 45% of the global population and is found in the Far East, parts of the Middle East, sub-Saharan Africa, parts of South America, and the Amazon basin, where at least 8% of the population are HBV chronic carriers (hepatitis B surface antigen [HBsAg] positivity rates > 8%) (Figure 1) (Int J Med Sci 2005;2:50-57). China seems to have become a "Leader in liver disease." Annually, more than 1,000 billion RMB is spent on HBV therapy and prevention, while the resulting indirect economic losses are inestimable. The reasons for the high rates of chronic HBV infection in China are complex. First, HBV infection has broad clinical manifestations, including asymptomatic carriers, acute hepatitis, and chronic (lifelong) hepatitis, due to different immune reactions by the host. However, little is currently known about the mechanisms for HBV's unremitting infection and long-term nonprogressive HBV infection of asymptomatic HBV carriers. Although a safe and effective vaccine against HBV has been available since 1982, there are still approximately 5~10% nonresponders to the hepatitis B vaccine. Moreover, little is known about the possible immunogenetic mechanisms of HBV-infected individuals developing cirrhosis and hepatocellular carcinoma, which are considered to be the biggest bottleneck for HBV therapy. Second, some social factors may explain the high rates of HBV infection. The public often pales at the mention of HBV infection, but they have incorrect perceptions or little knowledge about how hepatitis B is transmitted, resulting in inadequate self-prevention, unfounded prejudices, or unfair treatment of the chronically infected. Worse, even many physicians are not aware of the risk, the association between hepatitis B and liver cancer, the importance of HBV vaccination to prevent infection, and the need for carriers to have regular liver cancer screening. The latter is important because a carrier is an infected individual who does not develop the disease but can transmit the virus to others. Research has proven that the hepatitis B virus is mainly transmitted through body fluids like blood, semen, vaginal or menstrual secretions, serum, and wound exudates, and the virus has also been found in saliva, amniotic fl uid, tears, urine, feces, sweat, and mother's milk (Int J Med Sci 2005;2:50-57). Thus, people should actively acquire HBV-related knowledge, perform good hygiene, and heighten individual awareness of prevention to contain the transmission of HBV, which is of great importance to everyone. Finally, poor living habits are another important factor. In most rural areas in China, and especially in the poverty-stricken areas inhabited by smaller ethnic groups, people still lead poor lifestyles and have poor health habits, leading to their decreased immunity to HBV. This, to a certain extent, may be attributed to the inadequate public health advertising and financial input of the Government. Except in some large general hospitals, the sanitary conditions of most hospitals and rural health clinics still need to be improved, including a system of social relief and assistance. Another important aspect is attributed to people's lack of awareness concerning regular physical examinations. Many chronically infected individuals may not know that they have been infected because they feel perfectly healthy. By the time symptoms develop, however, action will be too late. The public is glad to see that a series of measures have been taken by Chinese authorities to provide effective HBV treatment and prevention. For instance, the "Wang Bao-En hepatic fibrosis research fund" was established by the China Foundation for Hepatitis Prevention and Control (CFHPC) on January 30, 2007 for the financial support of HBV research (Xinhua News, http://news.xinhuanet.com/health/2007-02/02/content 5687887.htm, available as of February 2, 2007). Similarly, the " Vaccination against Hepatitis B & Health Education Program," supported by the CFHPC, the Asian Liver Center at Stanford University, and several philanthropic foundations in Hong Kong, was formally inaugurated on August 31, 2007 to provide students of Qinghai Province with free and fullrange protection with hepatitis B vaccination (CFHPC News, http://www.cfhpc.net/CN/News/Detail.asp?gCatalogID=3&SystemID=79, available as of August 31,2007). The PRC is currently forming exceptional scientific teams, both from clinical and research institutes, to study the integrity, development, and natural history of HBV as well as mechanisms for unremitting HBV infection in terms of aspects such as the virus, host, and environment. In the meantime, researchers are endeavoring to develop novel anti-hepatitis virus drugs pursuant to the "Guideline for Prevention and Treatment of Chronic Hepatitis B" enacted at the end of 2004. As Health Minister Chen Zhu said, "China must cast its title of 'Leader in liver disease' into the Pacific Ocean because," he added, "we already have an extremely effective vaccine against HBV."

China's new drug R&D is steadily advancing

China appears to consistently lag behind developed countries like the US, Japan, and the nations of Europe in the development of pharmaceuticals, putting China in an embarrassing situation. In fact, China is still dependent on foreign imports for most highly effective cures to major diseases such as cancer, diabetes, hepatitis, and neurodegenerative disease. There is no denying the fact that governmental support, and especially a signifi cant amount of fi nancial support and political assistance to include government restructuring, is needed for the establishment of new drug Research and Development (R&D). Fortunately, China's authorities have recently recognized the importance of new drug development and have committed to implementing strong measures to help establish new drug R&D. This improvement in the government's status is showing immediate and substantial promise in the field of pharmaceuticals. On January 4, 2007, a research group directed by Wang Ming-Wei, Head of the National Center for Drug Screening, Shanghai Institute of Materia Medica (SIMM), made a breakthrough in the development of novel category I anti-diabetes drugs with the support of the Ministry of Science & Technology of China, the National Natural Science Foundation (NSFC) of China, and the Shanghai municipal government. Taking almost four years, the group finally developed a nonpeptide agonist of small molecule glucagon-like peptide 1 receptors with effi cacy in diabetic db/db mice (Proc Natl Acad Sci U S A 2007;104:943-948). As an antidiabetes drug, a peptide hormone traditionally had to be taken as an injection, which greatly limited its clinical application. In contrast, the new compound can be taken orally. This offers hope for the development of a new field of peptidomimetics for orally-available nonpeptide small molecules. Today, the ever-growing prevalence of major diseases worldwide is driving growth in new drug spending, encouraging the marketing of newly developed and effi cacious therapies. This achievement appears to have significantly boosted the field of new drug research in China. While "China's pharmaceutical firms lag far behind [their Western counterparts] in terms of biological preparations" "today's achievement, with the attention it has garnered, has important scientific signifi cance and potential social and economic value," said Chen Zhu, the minister of health PRC and also the former associate dean of the China Academy of Sciences (http://www.simm.ac.cn/News/20071417649.htm , available as of January 4, 2007). Other encouraging news came from the Shanghai Life Sciences Institute. A novel anti-HIV compound named Nifeviroc was developed with the support of the municipal government and licensed for clinical trials on April 17, 2007 (Shanghai Daily, April 17, 2007). This is expected to become the world's first oral HIV entryinhibitor. Thus far, applications to patent Nifeviroc have been submitted in 14 countries and regions, including the United States, Japan, and the European Union. Recently, Shanghai Targetdrug Pharmaceutical Company and Avexa, a Melbourne-based drug-research company in Australian, announced that they will jointly develop Nifeviroc for global distribution. Avexa will handle post-research expenses, develop the drug in the international marketplace, and share global profits with Targetdrug. Thus, China may have justified rationale and confidence to believe that the day will come when China's pharmaceutical products will boast a strong presence in the global market.