[Identification of Q-markers for Cistanches Herba based on HPLC-Q-TOF-MS/MS and network pharmacology]

This study aims to establish a method for analyzing the chemical constituents in Cistanches Herba by high performance liquid chromatography(HPLC) and quadrupole-time-of-flight tandem mass spectrometry(HPLC-Q-TOF-MS/MS), and to reveal the pharmacological mechanism based on network pharmacology for mining the quality markers(Q-markers) of Cistanches Herba. The chemical constituents of Cistanche deserticola and C. tubulosa were analyzed via HPLC-Q-TOF-MS/MS. The potential targets and pathways of Cistanches Herba were predicted via SwissTargetPrediction and DAVID. The compound-target-pathway-pharmacological action-efficacy network was constructed via Cytoscape. A total of 47 chemical constituents were identified, involving 95 targets and 56 signaling pathways. We preliminarily elucidated the pharmacological mechanisms of echinacoside, acteoside, isoacteoside, cistanoside F, 2'-acetylacteoside, cistanoside A, campneoside Ⅱ, salidroside, tubuloside B, 6-deoxycatalpol, 8-epi-loganic acid, ajugol, bartsioside, geniposidic acid, and pinoresinol 4-O-β-D-glucopyranoside, and predicted them to be the Q-markers of Cistanches Herba. This study identified the chemical constituents of Cistanches Herba, explained the pharmacological mechanism of the traditional efficacy of Cistanches Herba based on network pharmacology, and introduced the core concept of Q-markers to improve the quality evaluation of Cistanches Herba.

[The influence of chemotherapy-induced leucopenia on the disease-free survival of gastric cancer patients after radical gastrectomy]

Objective: To investigate the association between chemotherapy-induced leucopenia and patients' disease-free survival in gastric cancer patients who received radical gastrectomy. Methods: The clinical data of 273 gastric cancer patients who received radical gastrectomy and postoperative adjuvant chemotherapy between January, 2010 and December, 2015 in PLA 309(th) hospital was reviewed retrospectively. Results: A total of 195 (71.4%) patients experienced at least one time of leucopenia, while it was absent in the other 78 (28.6%) patients. The median disease-free survival of patients with or without leucopenia was 49.7 and 44.0 months respectively (P=0.009), leucopenia was an independent factor influencing patients' disease-free survival (HR=2.758, P=0.022), but there was no statistical difference between the disease-free survival of patients with different degrees and frequency of leucopenia (P=0.446, 0.123). Conclusion: Chemotherapy-induced leucopenia is a predictor of good prognosis for gastric cancer patients who receive radical gastrectomy.

Impact of human activities on subaqueous topographic change in Lingding Bay of the Pearl River estuary, China, during 1955-2013

Estuaries have been sites of intensive human activities during the past century. Tracing the evolution of subaqueous topography in estuaries on a decadal timescale enables us to understand the effects of human activities on estuaries. Bathymetric data from 1955 to 2010 show that land reclamation decreased the subaqueous area of Lingding Bay, in the Pearl River estuary, by ~170 km² and decreased its water volume by 615 × 10⁶ m³, representing a net decrease of 11.2 × 10⁶m³ per year and indicating the deposition of approximately 14.5 Mt/yr of sediment in Lingding Bay during that period. Whereas Lingding Bay was mainly governed by natural processes with slight net deposition before 1980, subsequent dredging and large port engineering projects changed the subaqueous topography of the bay by shallowing its shoals and deepening its troughs. Between 2012 and 2013, continuous dredging and a surge of sand excavation resulted in local changes in water depth of ± 5 m/yr, far exceeding the magnitude of natural topographic evolution in Lingding Bay. Reclamation, dredging, and navigation-channel projects removed 8.4 Mt/yr of sediment from Lingding Bay, representing 29% of the sediment input to the bay, and these activities have increased recently.

Security assessment of magnesium alloys used as biodegradable implant material

The security risk of magnesium alloys used as biodegradable implant material was evaluated in this study. Dose-response assessment was conducted by using toxicological data from authoritative public health agencies (World Health Organization) and assuming 1~3 years of uniform corrosion. Through modification calculation, the tolerable corrosion rate of biodegradable magnesium alloys in vivo was proposed, which theoretically ensured the bio-safety of the degradation products. The tolerable limits corresponding to various component elements in magnesium alloys were considered separately, although there are deficits in the toxicological data of some component elements. The influence of corrosion on the strength of magnesium alloys was evaluated, which would contribute to the rationally utilization of magnesium alloys as degradable implant materials. This study illustrates that not only toxicological calculations but also mechanical performance should be taken into consideration when developing novel degradable metallic implant.

Alteration of coenzyme specificity of malate dehydrogenase from Streptomyces coelicolor A3(2) by site-directed mutagenesis

We describe here for the first time the alteration of coenzyme specificity of malate dehydrogenase (MDH) from Streptomyces coelicolor A3(2) (ScMDH). In the present study, we replaced four amino acid residues in the Rossmann fold (βB-αC) region of NADH-dependent ScMDH by site-directed mutagenesis with those of NADPH-dependent MDH (Glu42Gly, Ile43Ser, Pro45Arg, and Ala46Ser). The coenzyme specificity of the mutant enzyme (ScMDH-T4) was examined. Coenzyme specificity of ScMDH-T4 was shifted 2231.3-fold toward NADPH using kcat/Km(coenzyme) as the measurement of coenzyme specificity. Accordingly, the effect of the replacements on coenzyme specificity is discussed. Our work provides further insight into the coenzyme specificity of ScMDH.

First Report of Fusarium equiseti Causing a Sheath Rot of Corn in China

Corn is the most important cereal crop in China. Over 34.94 million ha of corn is cultivated in the country annually. However, fungal diseases are a major limiting factor in corn production. In August 2008, 50 ha in several corn fields in Liaoning, Jilin, and Heilongjiang provinces were observed to be severely affected by a disease causing a yield loss of 30%. Results from field surveys suggested an epidemic during late corn growth stages that affected corn sheaths, causing irregularly circular spots with grayish brown to dark brown lesions. Lesions ranged from 2.5 to 3 × 3 to 5 cm. To isolate the causal agent, tissue was removed from the border of lesions and surface sterilized in 75% ethanol for 30 sec and 0.1% HgCl₂ for 1 min. The sample was then triple rinsed in sterile distilled water. The isolate was purified and subcultured on potato dextrose agar (PDA) at 25 ± 2°C. The initial color of the mycelium was white, turning brown after being cultured for 7 days. A pale brown to dark brown pigment developed in the agar beneath the colony. Chlamydospores, solitary but also in short chains, measuring 7.2 to 15.3 μm, were produced on carnation leaf agar (CLA) after 10 days and became verrucose 20 days later. Macroconidia were produced on CLA in orange sporodochia from monophialides on branched conidiophores, usually 5- to 7-septate, and apical cells were tapered and elongate. Basal cells were prominent, foot-shaped, and elongated in appearance. Microconidia were not observed (1). These morphological characteristics matched the description of Fusarium equiseti reported by Leslie and Summerell (1). A pathogenicity test was conducted with an isolate from each of the 36 corn plants by spraying 2 ml of spore suspension (10⁶ conidia/ml) on 45-day-old corn sheaths (cv. Huang Zao). For the control treatment, 36 corn plants were sprayed with an equal volume of sterilized water. Inoculated plants were placed in a greenhouse at 32 to 34°C and 95% relative humidity. Typical irregularly circular lesions were observed 7 days after inoculation, except in the control samples. Each treatment was replicated three times. The suspected pathogen was consistently re-isolated from diseased tissue according to Koch's postulates, and was found to be morphologically similar to F. equiseti. Preliminary morphological identification of the fungus was confirmed by a PCR assay using genomic DNA extracted from the mycelia of a 7-day-old culture on PDA at 25 ± 2°C. A 750-bp amplified region of the transcription elongation factor (TEF) of rDNA was generated using TEF1 (5'-ATGGGTAAGGAGGACAAGAC-3') and TEF2 (5'-GGAAGTACCAGTGATCATGTT-3') primers. The TEF region (GenBank Accession No. KF754798) was sequenced by Sangon Biotech Co., Ltd. (Shanghai, China) and displayed 99% nucleotide similarity with the rDNA-TEF of F. equiseti (JN127347.1) separately after a BLASTn search in GenBank. Based on the symptoms, fungal morphology, TEF sequence, and pathogenicity testing, this fungus was identified as F. equiseti. To our knowledge, this is the first report of F. equiseti on corn sheaths in China. This report will establish a foundation for further study of F. equiseti to address the disease effectively and to determine the severity of damage caused by F. equiseti. Reference: (1) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell, Ames, IA, 2006.

First Report of Elm Yellows Subgroup 16SrV-B Phytoplasma as the Cause of Rose Balsam Phyllody in China

Rose balsam (Impatiens balsamina L.) is an ornamental species frequently cultivated in China and the red flower is often used as nail polish in rural regions. The phytoplasmas previously reported with rose balsam phyllody in China have been classified as aster yellows group (16SrI) (1). In August 2012, some rose balsams were observed with typical phytoplasma symptoms in Handan City, Hebei Province, China, with an incidence of about 70% in the fields. The flowers turned green and petals fascicled. The new leaves wrinkled and deformed and internodes shortened. Infected plants were stunted, matured prematurely, and failed to produce seeds. To confirm phytoplasma infection, 100 mg of plant tissue (leaves, petals) was collected from five symptomatic and four asymptomatic plants and total DNA was extracted using a modified cetyltrimethylammonium bromide (CTAB) method (2). The 16S rDNA gene was amplified by nested PCR using primer pair P1/P7 followed by R16F2n/R16R2 (3). No amplicons were generated with DNA from asymptomatic samples, but amplicons of approximately 1.2 kb were obtained with DNA from five symptomatic samples. The amplified products were purified with aTIANgel midi purification kit (Tiangen, Beijing) and sequenced at the Sangon Biotech facility (Shanghai, China). The sequences of the amplicons were 100% identical and deposited in NCBI GenBank (Accession No. KC993832). The 16S rDNA gene sequence from this phytoplasma was 99% similar to Jujube witches broom phytoplasma (JQ675716), Puna chicory flat stem phytoplasma (JN582266), Plum yellows phytoplasma (FJ459914), and other elm yellows group phytoplasmas by BLAST search of the NCBI database. Restriction fragment length polymorphism (RFLP) analyses were carried out by digesting the 1.2-kb R16F2n/R16R2 nested PCR product with restriction enzymes AluI, RsaI, HhaI, HpaI, Eco RI, TaqI, HaeIII, HinfI, and KpnI (Takara, Dalian). The 16S rDNA RFLP patterns matched that of Jujube witches broom phytoplasma (JWB, subgroup 16SrV-B) (4). Nucleotide sequences of rose balsam phyllody were analyzed by iPhyClassifier software, which revealed that it had maximum similarity to the reference pattern of 16Sr group V, subgroup B (AB052876). All samples were detected with transmission electron microscopy. The results showed phytoplasma-like cells in phloem sieve element of symptomatic plants, while no phytoplasma-like cells were observed in healthy phloem tissues. The phytoplasma cells ranged from 230 to 470 nm in diameter and were ellipsoidal or orbicular with visible membranes. Combining the RFLP pattern and sequence analysis by iPhyClassifier, we classified the phytoplasma causing rose balsam phyllody into subgroup 16SrV-B. To our knowledge, this is the first report of 16SrV-B group phytoplasmas infecting rose balsam in China. References: (1) Z. N. Li et al. J. Phytopathol. 159:799, 2011. (2) M. A. Saghai-Maroof et al. Proc. Natl. Acad. Sci. 81:8014, 1984. (3) I. M. Lee et al. Phytopathology 83:834, 1993. (4) I. M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998.

First Report of Bipolaris papendorfii Causing Corn Leaf Spot in China

Corn is the most important cereal crop in China, with over 34.94 million ha being cultivated in the country annually. However, fungal diseases are a major limiting factor in corn production. In August 2012, 20 ha of corn fields in Anhui Province were found to be heavily infected by fungi. The margin of the lesion was achlorotic, and the middle was yellowish white or off-white, which was similar to the corn Curvalaria leaf spot. The oval lesions were approximately 5 to 7 mm. Lesion tissue was removed from the border between symptomatic and healthy tissue. The surface was sterilized in 75% ethanol for 30 s and 0.1% HgCl₂ for 1 min, after which the sample was washed three times in sterile distilled water. The isolate was purified and subcultured on potato dextrose agar (PDA) at 25 ± 2°C. The initial color of the colony was light brown, turning dark brown after being cultured for 7 days. The conidia were boat-shaped or inverted pear-shaped and were clearly bent to one side. The cells of both ends were slightly lighter and respectively ranged from 34.5 to 44.0 μm and 12.0 to 21.0 μm away from the base, with the second cell as the widest. The majority conidia had three or four false septates; isolates produced light brown to medium brown conidiophore, scattered or clustered, often branching, and exhibited bending. These morphological characteristics matched with the description of Bipolaris papendorfii reported by Zhang (3). A pathogenicity test was conducted with the two isolates on each of the 36 corns by spraying 2 ml spore suspension (10⁶ conidia/ml). For the control treatment, 36 corns were inoculated with an equal volume of sterilized water. Inoculated plants were placed in a greenhouse from 29 to 33°C and 95% relative humidity. The typical 5 to 7 mm oval lesions were observed 7 days after inoculation, except on the control samples. Three replications of 36 corns were used for each treatment. The isolate was consistently 100% reisolated from the diseased tissue according to Koch's postulate. The isolate was found to be morphologically similar to B. papendorfii. Preliminary morphological identification of the fungus was confirmed by PCR assay using genomic DNA extracted from the mycelium of a 7-day-old culture on PDA at 25 ± 2°C. A 550-bp amplified region of the internal transcribed spacer (ITS) of rDNA was generated using ITS1 (5'-TCCGTAGGTGAACCTGCGG-3') and ITS4 (5'-TCCTCCGCTTATTGATATGC-3') universal primers (1). The ITS region (GenBank Accession No. KC592365) was then sequenced by Sangon Biotech (Shanghai, China), and displayed 99% nucleotide similarity with the rDNA-ITS of B. papendorfii (JQ753972.1) separately after BLASTn research in GenBank. Based on the symptoms, fungal morphology, ITS sequence, and pathogenicity testing, this fungus was identified as B. papendorfii. The pathogen could reportedly infect tobacco and cotton (2). To our knowledge, this is the first study to report that B. papendorfii can infect corn in China. This report will establish a foundation for the further study of B. papendorfii to address the disease effectively. Further studies will be conducted to determine the incidence of the disease and the severity of damage caused by B. papendorfii as well as determine a possible mode for controlling the spread of the disease. References: (1) Y. J. Cao et al. Chin. J. Trop. Crops 31:1098, 2010. (2) H. Deng et al. Mycosystema 21:327, 2002. (3) T. Y. Zhang. Chin. Fungi Chi. 30:21, 2010.

Purification, characterization of two peptides from Buthus martensi Karch

A new peptide named Martentoxin I and an analogue Martentoxin were purified and characterized from the venom of Buthus martensi Karch. Martentoxin I consisted of 36 amino acid residues with molecular mass as 3908.0 Da determined by matrix-assisted laser desorption ionization time-of-flight-MS. The amino acid sequence was determined as GLIDVKCFASSECWTACKKVTGSGQGKCQNNQCRCY by Edman degradation. Martentoxin consisted of 37 amino acid residues with a molecular mass as 4055.3 Da and it showed highly sequence identity to Martentoxin I as FGLIDVKCFASSECWTACKKVTGSGQGKCQNNQCRCY. Estimation from circular dichroism spectra indicated Martentoxin I owned 18.0% alpha-helix, 53.0% beta-sheet structure and 3.9% turn while Martentoxin contained 13.3% alpha-helix, 64.3% beta-sheet structure and 1.1% turn. The toxicity assay showed both peptides had no toxic effects on mice up to the dose of 10 mg/kg. Electrophysiological studies showed that Martentoxin I and Martentoxin at the concentration of 1 microm significantly inhibited voltage-dependent Na+ current (INa) and voltage-dependent delayed rectifier K+ current (IK) but had no effects on transient K+ current (IA). Both interactions with Na+ and K+ channels were irreversible.

[The values of urine cysteine protein activity in the diagnosis of ovarian cancer]

The levels of urine cysteine protease (UCP) were detected in the urines of 70 gynecological cancers, 50 gynecological benign tumors and 50 normal women. The values of UCP assay of gynecological cancers were much higher than those of benign and normal samples (P < 0.01). Best cut off point for diagnosis of gynecological cancers was P95 and UCP cut off value was 0.24 pmol.min-1/L by using percentile and ROC curve. The sensitivity of UCP assay was 90%, specificity 80% and accuracy 86%. The sensitivity for ovarian cancers was 95%, but 77% and 85% for corpus and cervical cancers respectively. There were no differences between UCP and CA125 (sensitivity 85%, specificity 87%, accuracy 84%) in the diagnosis of ovarian cancers. In 7 cases of 8 cases of stage I ovarian cancers, UCP were abnormal. In 6 cases of the same group, CA125 were normal (< 35,000 U/L). So UCP may be better than CA125 in the diagnosis of early ovarian cancer. The sensitivity of lactate dehydrogenase (LDH) isoenzyme was 75% in ovarian cancer which was lower than UCP and CA125, but the specificity 85%. LDH isoenzyme still was one of important tumor markers for diagnosis. Combined assays with UCP, CA125 and LDH isoenzyme may reach the sensitivity 96% and specificity 100% evidently. These data implied that UCP may be a good tumor marker in gynecological cancers especially for ovarian cancers in future.

Isolation of a Degeneration-Resistant Mutant of Clostridium acetobutylicum NCIMB 8052

Unless periodically grown from germinated spores, Clostridium acetobutylicum tends to degenerate (that is, to spontaneously lose the capacity both to produce solvents and to develop into spores). To obtain mutants that are deficient in degeneration, C. acetobutylicum NCIMB 8052 was mated with Enterococcus faecalis BM4110 harboring transposon Tn 1545 . We developed a degeneration resistance assay based on a secondary effect of degeneration, the production of toxic levels of acetic and butyric acids. Erythromycin-resistant transconjugant clones were tested individually for longevity by repeated and timely subculturing. One long-lived mutant, A10, survived 18 ± 3 transfers (mean ± standard deviation; n = 20) before extinction, while the wild type (parental cells) survived 6.6 ± 1.5 transfers ( n = 11). The three-fold difference in longevity is statistically significant. In a batch culture in a rich medium, the wild-type cells degenerated within 24 h after inoculation with 1% of an overnight culture derived from germinated spores. In contrast, A10 cells were able to switch to solventogenesis and to sporulate. In a minimal medium with greater buffering capacity, both cell types produced solvents and spores. Southern blots of Eco RI and Hin dIII restriction digests of A10 chromosomal DNA (but not parental DNA) showed that only one copy of Tn 1545 was inserted into the clostridial chromosome. Our findings are consistent with the hypothesis that there was an alteration at a regulatory locus that was effected by the insertion of the transposon.

[Endometrial carcinoma in young women]

Two hundred and fifty-four patients with endometrial carcinoma were diagnosed and treated from Feb. 1956 to Apr. 1987. Of these, 35 patients were below the age of 40 years at the time of diagnosis. These patients were analyzed and compared with those aged above 40. The main clinical manifestations were primary sterility and irregular menstruation. An endometrial carcinoma should be suspected in young women with menstruation disorder, sterility and follicular cyst of ovary refractory to treatment. The highly differentiated endometrial carcinoma in young women was easily confused with adenomatous hyperplasia and should be diagnosed with caution. In young patients with stage I well-differentiated disease desirous of childbirth, treatment by large dose of progestogens without hysterectomy may be the method of choice. Estimation of estrogen and progesterone receptors was very helpful in selecting therapeutic modalities and predicting prognosis. The difference of 5-year survival rates between these two groups of patients were not statistically significant.

[Comparative study on human chorionic gonadotropin receptor in normal human ovary with ovarian tumors]

Human Chorionic Gonadotropin (HCG) is major physiological luteotropic factors for the human corpus luteum. The observations strongly suggest that the human ovary possesses a gonadotropin receptor in the cell membrane. We studied the HCG receptor in normal human ovary and ovarian tumors. Twenty-three human ovarian specimens and 16 ovarian tumor specimens were obtained from women patients having gynecological surgery. Ovaries were homogenized and sonicated. The homogenates were centrifuged at 2000 g for 15 min. After sucrose density gradient ultracentrifugation (78,000 g, 4 h), two fractions were collected from layer of 33% and interface between 33% and 37%. Thirty micrograms of ovarian protein, 8 ng 125I-HCG and unlabeled HCG in a final volume of 0.5 ml of 0.05 mol/L Tris buffer were incubated at 30 degrees C for 2 h. The results were shown in the table.

[Estrogen and progesterone receptors in human ovary and ovarian tumors]

Ovarian specimens from 159 different patients were analyzed for estrogen and progesterone receptor (ER and PR) content with the Dextran-coated Charcoal method. The results indicated that the contents of ER and PR in malignant ovarian tumors were not correlated with the menstrual cycle of the patient, clinical stage and differentiation of the tumor. Among malignant ovarian tumors, the mean ER and PR concentrations in sex-cord stromal tumors and endometrioid carcinomas were higher than those in other malignant ovarian tumors (P less than 0.05, P less than 0.025). This suggests the possibility of endocrine therapy for these patients with the hope for a better prognosis.

Cytosol estrogen and progesterone receptor levels measured in normal and pathological tissue of endometrium, endocervical mucosa and cervical vaginal portion

The aim of this study was to compare cytosol estrogen (ER) and progesterone (PgR) receptor levels measured in normal and pathological tissue specimens (n = 395) of endometrium (ED), endocervical mucosa (EM) and cervical vaginal portion (VP) from 108 patients (age 27-79). The highest ER levels were found in ED which decreased to 25% in VP. The PgR decline was more pronounced in VP since the majority of samples were PgR-negative. In addition pathological tissue from ED exhibited marked differences in steroid receptor levels: The highest ER and PgR concentrations were detected in the proliferative phase, whereas the secretory phase exhibited significantly reduced ER and PgR levels. The lowest ER and PgR amounts were measured in atrophic and quiescent tissues; in proliferative tissue ER and PgR levels were comparable to hyperplastic tissue. Cervical ER and PgR concentrations were significantly lower as compared with ED (25-30%), and no cyclic variations were detectable. Also ER and PgR levels were different between EM and VP. 96% of ER were positive in the cervix, whereas 73% were PgR-negative in VP. Furthermore an inverse correlation between ER and progesterone was found in ED and a positive correlation between estradiol and PgR. These results suggest that the cytosol ER and PgR levels vary markedly in the uterine corpus and may explain in part the different response to endocrine therapy.