Angled cavity photonic crystal laser diodes with tilted sidewalls for improving far-field patterns

Angled laser diodes based on the longitudinal photonic band crystal (PBC) waveguide are first proposed and fabricated at a wavelength of 905 nm. Tilted sidewalls are utilized to reflect the light downward, thus enlarging the transverse mode size. In the experiment, continuous wave (CW) output power of 630  mW/facet is achieved, and stable and narrow divergence angles are obtained in the fast and slow axes, simultaneously. The transverse angle is reduced by 44% compared with that of the conventional broad area (BA) laser based on the same wafer, and the lateral angle is only 1.65° with on-axis main-lobe emission. This device shows a promising future for laser emission with ultra-narrow divergence and easy fabrication.

A generic plant RNA isolation method suitable for RNA-Seq and suppression subtractive hybridization

A recently developed revolutionary approach to transcriptomics, RNA-Seq, and suppression subtractive hybridization are powerful tools for gene expression research. However, currently, the difficulty of isolating high-quality RNAs from plant tissues bearing abundant complex polysaccharides, polyphenolics, and secondary metabolites is a serious problem that not only limits the application of these technologies but also hinders studies dealing with RNA in general. We have developed a consistent protocol to prepare highly intact and pure RNAs from tissues of a variety of field-grown plant species, with high yields, in 2 to 3 h. Additionally, this method can be readily applied to mammalian, yeast, and bacterial cells.

Relapse of hyperthyroidism after hemithyroidectomy in concurrent medullary thyroid cancer and Graves' disease

We present a rare case of concurrent medullary thyroid cancer (MTC) and relapse of Graves' disease (GD). A 26-year-old Chinese female suffered from GD for 1 year. Physical examination demonstrated mildly diffuse goiter with a palpable 1.0 cm nodule in the right thyroid lobe and exophthalmos. Before hemithyroidectomy, calcitonin was elevated and thyroglobulin was normal. After surgery, histopathological findings proved coexistence of MTC and GD. 16 months later, GD relapsed and radioactive iodine 131 therapy was given. Meanwhile, postoperative monitoring showed well controlled calcitonin and carcinoembryonic antigen. Our lesson demonstrates although concomitant of MTC and GD is very rare, yet after hemithyroidectomy for the single nodular MTC lesion, remnant thyroid lobe could be the source of GD relapse very soon. More importantly, the relapse of GD and the following radioiodine therapy and radiation exposure could have been prevented if a better therapy plan of total thyroidectomy was adopted in the first place, instead of hemithyroidectomy (Tab. 1, Fig. 2, Ref. 11).

Expression of cytochrome P450 1A1/2 and 3A4 in liver tissues of hepatocellular carcinoma cases and controls from Taiwan and their relationship to hepatitis B virus and aflatoxin B1-and 4-aminobiphenyl-DNA adducts

Cytochrome P450 enzymes play a major role in the metabolism of several of the chemical carcinogens involved in the development of hepatocellular carcinoma (HCC). To investigate by immunohistochemistry interindividual differences in these enzymes, polyclonal antisera and immunoperoxidase staining were used to detect the expression of CYP1A1/2 and 3A4 in 37 surgical control tissues and 105 tumour and adjacent nontumour tissues of HCC cases from Taiwan. There was variability in the expression and staining pattern for both CYP1A1/2 and 3A4 in all tissue types. In tissues from controls, there was no correlation between P450 expression and smoking history or hepatitis B virus antigen status. Since these samples had been previously analysed for the DNA adducts of aflatoxin B1 (AFB1), a dietary mould contaminant, and 4-aminobiphenyl (4-ABP), a component of cigarette smoke, we also investigated the relationship between P450 levels and DNA adducts. 4-ABP-DNA adducts were higher in tissues with elevated levels of CYP1A1/2 (p = 0.02). Overall there was no relationship between CYP1A1/2 or CYP3A4 and AFB1-DNA adducts in control tissues. Staining intensity for CYP1A1/2 and 3A4 followed the order: tumour tissues < control tissues < adjacent non-tumour tissues. CYP1A1/2 levels tended to be lower in tumour and adjacent non-tumour tissues than for CYP3A4. In HCC cases, 4-ABP-DNA adducts were higher in subjects with higher levels of CYP1A1/2, stratified by tissue type, but these differences were not significant. For CYP3A4, in contrast to control tissues, there was a significant association with AFB1-DNA adducts in tumour and adjacent non-tumour tissue of HCC cases. These results suggest that one factor influencing carcinogen-DNA adducts is levels of specific P450 enzymes. However, adduct formation in vivo is a complex processes dependent upon numerous genetic and environmental factors.

Formation of a stable p-n junction in a liquid-gated MoS2 ambipolar transistor

Molybdenum disulfide (MoS2) has gained attention because of its high mobility and circular dichroism. As a crucial step to merge these advantages into a single device, we present a method that electronically controls and locates p-n junctions in liquid-gated ambipolar MoS2 transistors. A bias-independent p-n junction was formed, and it displayed rectifying I-V characteristics. This p-n diode could perform a crucial role in the development of optoelectronic valleytronic devices.

Optimal combination of radiotherapy and endocrine drugs in breast cancer treatment

PURPOSE

Breast cancer is the most common cancer in women. Radiotherapy is considered a standard treatment option after surgery and adjuvant endocrine therapy is also universally used. Tamoxifen and letrozole are the current first-line endocrine therapy drugs. However, information has been scarce about how best to sequence these therapies to maximize their effectiveness and keep toxic effects to a minimum. In this study, we observed the effect of different sequence combination of radiotherapy and endocrine drugs, tamoxifen or letrozole, to get the best treatment sequence.

MATERIALS AND METHODS

The combination effect of radiotherapy and tamoxifen was observed on breast tumour cell line MCF-7, radiotherapy and letrozole on aromatase-expressing breast tumour cell line MCF-7CA. Irradiation was performed with 6Gy, except for doses ranging from 0 to 8Gy for clone formation assay. Tamoxifen or letrozole was added before or after irradiation, respectively. Radiosensitivity was evaluated by clonogenic assay, cell viability by 3-(4,-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay. To explore the potential mechanism, cell apoptosis was determined by DNA-binding dye 4',6-diamidino-2-phenylindole dihydrochloride (DAPI) assay, the change of Bcl-2 and Bax expression was by western blot.

RESULTS

Although no significant statistical difference was observed between different sequence, tamoxifen and letrozole both increased radiosensitivity. Furthermore, the above inhibitory effect was related with apoptosis signaling pathway, especially Bcl-2 and Bax.

CONCLUSION

Taken together, these results suggested that endocrine drugs, such as tamoxifen and letrozole, have potential application with radiotherapy.

First Report on the Occurrence of A2 Mating Type of the Cucurbit Downy Mildew Agent Pseudoperonospora cubensis in China

Pseudoperonospora cubensis is a foliar pathogen of cucurbits. In cucumber, it produces chlorotic, angular lesions with dark sporangia on their under-surface. The distribution of pathotypes and mating types of P. cubensis were investigated in seven provinces in China. Twenty-nine isolates were obtained from Guangdong, Anhui, Hubei, Sichuan, Shandong, Beijing, and Harbin, one to six isolates from each province. They were collected from cucumber during summer 2011, except those from Harbin, which were collected from cucumber in summer 2012. Isolates were tested for pathogenicity and mating type. Pathogenicity was tested by inoculation of detached leaves of: cucumber (Cucumis sativum cvs. Bet-Alpha, SMR18), melon (Cucumis melo reticulatus cv. Ananas-Yokneam), pumpkin (Cucurbita maxima cv. Tripoli), squash (Cucurbita pepo, cv. Beruti), butternut gourd (Cucurbita moschata cv. Waltham), watermelon (Citrullus lanatus, cv. Malali), and sponge gourd (Luffa cylindrica, cultivar unknown). Mating type was determined by oospore production in melon leaf discs inoculated with mixed sporangia of a test isolate and A1 or A2 tester isolates, as recently described (2). The results showed that 22 isolates belonged to pathotype 3, sporulating on cucumber and melon; five isolates belonged to pathotype 6, sporulating on cucumber, melon, pumpkin, squash, and butternut gourd; one isolate belonged to pathotype 5, sporulating on the above five species and watermelon (1), and one isolate was capable of sporulating on the mentioned five species and sponge gourd, herein called pathotype 7. Of the 29 isolates tested, 22 belonged to the A1 mating type, six to the A2 mating type, and one did not produce oospores with either testers. Of the six A2 isolates, two originated from Sichuan, one from Beijing, and three from Harbin. All 22 isolates belonging to pathotype 3 were A1, whereas the other six isolates (four pathotype 6, one pathotype 5, and one pathotype 7) were A2. Crosses made between Chinese isolates belonging to opposite mating types resulted in the formation of abundant oospores in detached melon or cucumber leaves. The results prove that the A2 mating type of P. cubensis occurs in China. This explains the abundant occurrence of oospores of P. cubensis in nature in China (4). The data corroborate with Runge et al. (3), who suggested that the recent changes in the population structure of P. cubensis around the world resulted from the migration of a new genotype of P. cubensis from the Far East to Europe and the U.S.A. In Israel, a new pathotype attacking both Cucumis and Cucurbita appeared in 2002 (1), and A2 mating type first appeared in 2010 (2). References: (1) Y. Cohen et al. Phytoparasitica 31:458, 2003. (2) Y. Cohen and A. E. Rubin. Eur. J. Plant Pathol. 132:577, 2012. (3) F. Runge et al. Eur. J. Plant Pathol. 129:135, 2011. (4) Y. J. Zhang et al. J. Phytopathol. 160:469, 2012.

First Report of Hosta virus X Infecting Hosta Plants in China

Hosta (Hosta spp.) plants showing leaf deformation, puckering, and ink-bleed symptoms were collected in July 2012 from a park at Dongcheng district, Beijing, China. Three out of six samples tested positive for Hosta virus X (HVX) by immunostrip and double-antibody sandwich (DAS)-ELISA with HVX-specific serological reagents from Agdia Inc. (Elkhart, IN, USA). Filamentous viral particles were trapped and observed from the infected hosta leaf sap by immuno-serological electron microscopy (ISEM) (antibodies from Agdia). To confirm HVX infection, three ELISA-positive samples were analyzed by reverse transcription-PCR assay, using virus-specific primers HVXf (5'-ATCCGTTATCTACAGGGGACCAG-3') and HVXr (5'-TAAGTTAGTGGAACGGTTAGCCCGAT-3') that amplified a 1,067-bp fragment including the coat protein (CP) coding region. The CP nucleotide sequence comparisons showed 99% to 100% homology among the three isolates named HVXBJ4, HVXBJ5, and HVXBJ6 (GenBank Accession No. JX535292, JX535293, and JX535294) and with the HVX sequences previously reported in GenBank. HVX has been reported from the United States, Korea, the Netherlands, Poland, France, the Czech Republic, and New Zealand (1,2). To our knowledge, this is the first report of HVX infecting hosta plants in China. As an ornamental and medicinal plant, hosta has been cultivated in China for more than 2,000 years. The presence of HVX in Beijing is a potential threat to the landscape in the city. HVX can be spread by vegetative propagation material or mechanical contact (3). Hence, to cultivate HVX-free hosta and restrict the movement of HVX-infected hosta is vitally important in the future. HVX has become economically important in the world more recently. Globalization of trade in hosta plants has increased the risk of movement of HVX. The national plant protection organization should establish effective quarantine strategy and the growers take proper planting measures to avoid further spreading of this virus. References: (1) S. Currier et al. Plant Dis. 80:1040, 1996. (2) M. H. Park et al. Arch. Virol. 148:2039, 2003. (3) K. H. Ryu et al. Acta Hortic. 722:91, 2006.

Association between CASP-8 gene polymorphisms and cancer risk in some Asian population based on a HuGE review and meta-analysis

Genetic variation in the CASP-8 gene reportedly can increase cancer susceptibility by regulating tumor cell proliferation and apoptosis. Several studies have investigated this possibility; however, the conclusions remain controversial. We made a Human Genome Epidemiology (HuGE) review and did a meta-analysis to explore the association between CASP-8 gene polymorphisms and cancer risk in Asian populations. Based on the inclusion criteria, 12 case-control studies comprising 7720 cancer cases and 9404 healthy controls were retrieved. Meta-analysis results showed that the rs3834129*del allele/carrier were associated with decreased risk of cancer in Asian populations [del allele: odd ratio (OR) = 0.79, 95% confidence interval (95%CI) = 0.75-0.83, P < 0.001; del carrier: OR = 0.77, 95%CI = 0.72-0.82, P < 0.001]. Subgroup analysis showed that the rs3834129*del allele/carrier are protective factors for cancer risk in Chinese populations (del allele: OR = 0.77, 95%CI = 0.73-0.81, P < 0.001; del carrier: OR = 0.75, 95%CI = 0.70-0.80, P < 0.001), but not in Indian and Korean populations. Furthermore, the rs6704688*T allele/carrier, rs3769827*C allele/carrier, rs3769825*C allele/carrier were associated with decreased risk of cancer in Asian populations (all P < 0.05). While the rs7608692*A allele was associated with increased risk of cancer risk in Asian populations (OR = 1.35, 95%CI = 1.02-1.78, P = 0.03). There was also no significant association between rs3769818, rs13030042, rs13030042, rs1045494, rs1045494, rs2823, or rs113686495, and cancer risk in Asian populations (all P > 0.05). This meta-analysis suggests that the rs3834129*del allele/ carrier, rs6704688*T allele/carrier, rs3769827*C allele/carrier, and rs3769825*C allele/carrier might be protective factors for cancer risk in Asian populations, while the rs7608692*A allele might be a risk factor for cancer risk in Asian populations.

Efficient isolation of high-quality RNA from lotus Nelumbo nucifera ssp nucifera tissues

Nelumbo nucifera is widely used as food, as an ornamental, in medicine, and as packing material; it is also reported to have anti-HIV effects and antioxidant capacity. We sought an improved method for extracting high-quality total RNA from different tissues of N. nucifera. Four methods for RNA extraction were assessed for their ability to recover high-quality RNA applicable for evaluation of polyphenol oxidase (PPO) gene expression profiles. The recovery and quality of the RNA obtained from five different tissues by the best CTAB-LiCl method were evaluated through UV light absorbance. Both A(260)/A(280) and A(260)/A(230) absorbance ratios were more than 2.0; the yield ranged from 59.87 to 163.75 μg/g fresh weight. The brightness of the 28S band was approximately twice that of 18S; the latter was also considered as high-quality RNA. The PPO gene fragment (606 bp) was successfully amplified by RT-PCR, demonstrating the integrity of the isolated RNA. The relative expression levels of the PPO gene based on RT-PCR in five tissues of lotus were: rhizome buds (2.66), young leaves (2.42), fresh cut rhizome (2.02), petals (1.80), and petiole (1.65), using housekeeping gene β-actin as an internal control. We concluded that the total RNA isolated by this protocol is of sufficient quality for molecular applications.

The protective effect of curcumin on Aβ induced aberrant cell cycle reentry on primary cultured rat cortical neurons

OBJECTIVES

Alzheimer's disease (AD) is a neurodegenerative disorder marked by progressive loss of memory and impairment of cognitive ability. One current hypothesis for AD pathogenesis is that neuronal death is linked to aberrant cell-cycle re-entry. In AD, neurons have been shown to enter the cell cycle inappropriately without the ability to complete it fully and the aberrant re-entry leads to its death. Curcumin has been reported as having a neural protective effect on the AD model, and could modulate the proliferation of tumor cells through the regulation of cyclin D1 and c-myc cell signaling pathways. In this study, we first observed the protective action of curcumin on Abeta-induced neuron damage, and then investigated whether this protective effect was a result of the inhibition of cell cycle advance.

MATERIALS AND METHODS

We used MTT assay and TUNEL assay to observe the effect of curcumin on Abeta-induced neuron death, and then examined the activated caspase-3 protein level to further confirm the protective effect of curcumin against Abeta-induced neuron toxicity. Next, we further investigate whether the inhibition of cell cycle reentry was mediated by the therapeutic effect of curcumin on Abeta induced primary cultured neuron damage by Brdu label assay and western blot assay.

RESULTS

The results showed that administration of curcumin (1-10 microM) could inhibit Abeta25-35 (40 microg/ml) induced primary cultured rat cortical neuron death, down-regulating activated caspase-3 protein expression. Furthermore, treatment with curcumin could inhibit abnormal activated cyclin D1 protein level, and decrease the Brdu positive cells in proportion to the Abeta25-35 treatment neurons.

CONCLUSIONS

All the results suggest that curcumin has a protective effect against Abeta-induced toxicity in cultured rat cortical neurons, the inhibition of cell cycle re-entry at least partly mediating the therapeutic effect of curcumin in the AD model in vitro.

Contributions of heme oxygenase-1 in postconditioning-protected ischemia-reperfusion injury in rat liver transplantation

BACKGROUND

Heme oxygenase-1 (HO-1), an oxidative stress-response gene up-regulated by various physiological and exogenous stimuli, has cytoprotective activities. Ischemic postconditioning (Postcon) can protect an organ from ischemia-reperfusion (I/R) injury. In the present study, we investigated the potential contributions of HO-1 to Postcon-dependent protection against I/R injury in rat liver transplantation models.

MATERIALS AND METHODS

Adult male Sprague-Dawley rats were randomly divided into four groups: sham group with laparotomy for liver exposure; I/R group with 24-hour cold ischemia of the donor liver; Postcon group with the same treatment as the I/R group plus ischemic Postcon; and zinc protoporphyrin (ZnPP HO-1 inhibitor) + Postcon group treated the same as the Postcon cohort with donors pretreated using ZnPP 24 hours before the I/R injury. We measured liver tissue and peripheral blood samples collected at 6 hours after reperfusion and serum transaminase levels, histopathology, liver tissue malondialdehyde (MDA) content, superoxide dismutase (SOD) activity and HO-1 expression in the liver.

RESULTS

Postcon significantly diminished the elevation of serum transaminases levels after I/R injury when compared with I/R and ZnPP+Postcon groups. Postcon treated rats showed significantly lower MDA production and higher SOD activity. HO-1 was induced in rat livers exposed to Postcon; its levels were obviously overexpressed after 6 hours in Postcon rats. Inhibiting the expression of HO-1, negated the protective effects of Postcon.

CONCLUSIONS

Induction of HO-1 in the Postcon condition played a protective role against hepatic I/R injury and enhanced the early antioxidative activity. The protective effects of Postcon were significantly associated with greater intrahepatic HO-1 expression.

Investigation of the genetic diversity of an invasive whitefly (Bemisia tabaci) in China using both mitochondrial and nuclear DNA markers

It is often considered that reduced genetic variation due to bottlenecks and founder effects limits the capacity for species to establish in new environments and subsequently spread. The recent invasion (during the past five years) of an alien whitefly, one member of Bemisia tabaci cryptic species complex, referred to as Mediterranean (herein referred to as Q-type) in Shandong Province, China, provides an ideal opportunity to study the changes in genetic variation between its home range in the Mediterranean region and its invasion range. Using both the mitochondrial cytochrome oxidase I (mtCOI) and nuclear (microsatellite) DNA, we show that Q in Shandong likely originated in the western Mediterranean. We also found that the haplotype diversity was low compared with its presumed geographic origin, whereas microsatellite allele diversity showed no such decline. A key factor in invasions is the establishment of females and so bottleneck and founder events can lead to a very rapid and considerable loss of mitochondrial diversity. The lack of haplotype diversity in Shandong supports the interpretation that, at one or more points between the western Mediterranean and China, the invading Q lost haplotype diversity, most probably through the serial process of establishment and redistribution through trade in ornamental plants. However, the loss in haplotype diversity does not necessarily mean that nuclear allelic diversity should also decline. Provided females can mate freely with whichever males are available, allelic diversity can be maintained or even increased relative to the origin of the invader. Our findings may offer some explanation to the apparent paradox between the concept of reduced genetic variation limiting adaptation to new environments and the observed low diversity in successful invaders.

Further insights into the strange role of bacterial endosymbionts in whitefly, Bemisia tabaci: comparison of secondary symbionts from biotypes B and Q in China

The percentage infection of secondary symbionts (SS) (Wolbachia, Arsenophonus, Rickettsia, Hamiltonella, Fritschea and Cardinium) in the exotic Bemisia tabaci (Genn.) invaders, commonly known as biotypes B and Q from China, were determined by PCR. In total, 373 biotype B and 1830 biotype Q individuals were screened for the presence of SS. Biotype B was more abundant than biotype Q from 2005 to 2006, and biotype Q was more abundant from 2007 to 2009. Each of the SS, with the exception of Fritschea, was detected in both biotypes B and Q; Fritschea was found in none of the samples examined. For biotype B, the percentage infection of Hamiltonella was the highest (92.0%) followed by Rickettsia (70.2%). For biotype Q, the percentage infection of Hamiltonella was again the highest (73.3%). Arsenophonus was the least common of the SS observed in both biotypes B and Q. The percentage infection of Wolbachia, Rickettsia and Hamiltonella in biotype B was each significantly higher than in biotype Q, whereas the percentage infection of Cardinium in biotype B was significantly lower than in biotype Q. The percentage infection of SS in biotypes B and Q varied from year to year over the period 2005-2009. Furthermore, within biotype Q, two distinct subgroups were identified which differ from each other in terms of their SS complement. We discuss these results in the light of the potentially influential factors and roles of the SS.

Studies on interaction of cucurbit aphid-borne yellow virus proteins using yeast two-hybrid system and bimolecular fluorescence complementation

In this article, yeast two-hybrid system (YTHS) and bimolecular fluorescence complementation (BiFC) were used to analyze the interactions of cucurbit aphid-borne yellows virus (CABYV)-encoded proteins. P0, P1, P1-2, P3, P4, and P5 were tested by YTHS in all possible pairwise combinations, and only P3/P3 interaction was detected. Results obtained by BiFC further confirmed the self-interaction of P3, and the subcellular localization of reconstituted YFP fluorescence was observed mainly in nuclei of Nicotiana benthamiana leaf epidermal cells. Domains involved in P3/P3 self-interaction were analyzed by YTHS and BiFC using deletion mutants. The results showed that R domain (residues 1-61) in the N-terminus could self-interact, and it also interacted with the S domain (residues 62-199) in the C-terminus of P3. The present work would serve as a molecular basis for further characterization of CABYV proteins, and the regions involved in P3/P3 self-interaction could provide the clue for understanding the capsid assembly pathway of CABYV.

A simple method of genomic DNA extraction suitable for analysis of bulk fungal strains

AIMS

A simple and rapid method (designated thermolysis) for extracting genomic DNA from bulk fungal strains was described.

METHODS AND RESULTS

In the thermolysis method, a few mycelia or yeast cells were first rinsed with pure water to remove potential PCR inhibitors and then incubated in a lysis buffer at 85 degrees C to break down cell walls and membranes. This method was used to extract genomic DNA from large numbers of fungal strains (more than 92 species, 35 genera of three phyla) isolated from different sections of natural Ophiocordyceps sinensis specimens. Regions of interest from high as well as single-copy number genes were successfully amplified from the extracted DNA samples. The DNA samples obtained by this method can be stored at -20 degrees C for over 1 year.

CONCLUSIONS

The method was effective, easy and fast and allowed batch DNA extraction from multiple fungal isolates.

SIGNIFICANCE AND IMPACT OF STUDY

Use of the thermolysis method will allow researchers to obtain DNA from fungi quickly for use in molecular assays. This method requires only minute quantities of starting material and is suitable for diverse fungal species.

Performance of PAC/PDM composite coagulants for removal of algae from Lake Taihu waters in summer

The enhanced coagulation of algae-rich raw water from Lake Taihu in summer was studied by use of composite coagulants. The composite coagulants were composed of polyaluminum chloride (PAC) and polydimethyldiallylammonium chloride (PDM) with various intrinsic viscosity values (0.55-3.99 dL/g) and different mass percentages (5-20%) in the formulation. For raw water with temperature of 28-29 degrees C and algae content of 3.60x10(4)-3.70x10(4) cells/ml, the algae-removal rates of 89.0% and 89.3-93.1% could be realized by using PAC and PAC/PDM (0.55/5%-3.99/20%) with dosages of 8.37 mg/L and 5.93-3.58 mg/L, respectively, when 2 NTU residual turbidity of treated water after sedimentation was required. Compared with using PAC only, the removal rate of CODMn using PAC/PDM increased at least 4.4% when the dosage was 8 mg/L, and increased at least 5.0% when the dosage was 10 mg/L. The composite coagulants could still function well when raw water quality deteriorated and algae content reached 8.00x10(4) cells/ml. The enhanced coagulation efficiency of PAC/PDM (0.55/5%) could be better than that of PAC combined with prechlorination process when the same dosages are used.

Association between sexual precocity and alleles of KISS-1 and GPR54 genes in goats

KISS-1 and GPR54 were regarded as key regulators for the puberty onset and fundamental gatekeepers of sexual maturation in mammals. To explore the possible association between variations in KISS-1 and GPR54 with sexual precocity, mutation screening of exon 1 of KISS-1 and exon 1, exon 3, and partial exon 5 of GPR54 was performed in a sexual precocious breed (Jining Grey goats) and sexual late-maturing breeds (Inner Mongolia Cashmere, Angora, and Boer goats) by PCR-SSCP. The results showed that five novel mutations were identified in exon 1 and partial exon 5 of GPR54 including C96 T, T173C, G176A, G825A, and C981 T. The Jining Grey goats with genotype BB or AB had 1.07 (P < 0.05) or 0.40 (P < 0.05) kids more than those with AA. The Jining Grey goats with genotype DD or CD had 1.80 (P < 0.05) or 0.55 (P < 0.05) kids more than CC, respectively. The present study preliminarily showed an association between alleles B and D of GPR54 with high litter size and sexual precocity in Jining Grey goats.

In vitro and in vivo anticancer activity of steroid saponins of Paris polyphylla var. yunnanensis

AIM

To confirm the anticancer activity of steroid saponins isolated from the rhizome of Paris polyphylla var. yunnanensis and evaluate the structure-activity relationships of these steroid saponins in vitro and in vivo .

MATERIALS AND METHODS

Eight known steroid saponins were isolated from the rhizome of Paris polyphylla . The LA795 lung adenocarcinoma cell line from mice was chosen to evaluate cytotoxicity by means of MTT assay, and to study apoptosis by means of AnnexinV-FITC/PI flow cytometry. Diosgenin-3alpha-L-arabinofuranosyl(1-->4)-[alpha-L-rhamnopyranosyl(1-->2)]-beta-D-glycopyranoside (compound 1), the main steroid saponin of Paris polyphylla , and diosgenin (Dio), the aglycone of major steroid saponins, were evaluated for antitumor activity on LA795 lung adenocarcinoma in T739 inbred mice.

RESULTS

The steroid saponins showed remarkable cytotoxicity and caused typical apoptosis in a dose-dependent manner. They were evaluated in vivo by their effect on tumor developed in T739 inbred mice. The oral administration to T739 mice bearing LA795 lung adenocarcinoma of compound 1 and diosgenin significantly inhibited tumor growth, by 29.44% and 33.94%, respectively. HE staining showed that lungs and livers of treated mice underwent various levels of histopathological alterations. It was demonstrated by TUNEL assay that apoptosis rate in tumor cells was increased in comparison to cells in control mice. The 3-O-glycoside moiety and spirostanol structure played an important role in the anticancer activity of steroid saponins, and the number and the variety of glycosides of compounds strongly influenced on their anticancer activity.

CONCLUSION

Rhizoma Paridis saponins showed anticancer activity against lung adenocarcinoma cell line, both in vitro and in vivo, and their effect was dependent on compounds' structure in a certain degree.

Occurrence of Cucumber green mottle mosaic virus on Cucurbitaceous Plants in China

Cucumber green mottle mosaic virus (CGMMV) was first discovered in 2003 in China (2) and developed an epidemic during 2005 (1). To know the occurrence scale and damage level of CGMMV, a survey was carried out in the main areas of cucurbitaceous plant production and seed trading in 2006 and 2007 in Mainland China. Samples of 739 plants of 16 types (seed samples from Cucurbita moschata, Cucumis melo, Lagenaria siceraria, Cucumis sativus, Momordica charantia, L. siceraria var. clavata, and C. pepo, leaf samples from C. moschata, Cucumis melo, L. siceraria, Cucumis sativus, and M. charantia, fruit samples from C. moschata, Citrullus lanatus, and L. siceraria, and seedling samples from Citrullus lanatus) were collected from 13 regions and analyzed by a double antibody sandwich (DAS)-ELISA. CGMMV was detected in Citrullus lanatus, L. siceraria, Cucumis melo, and C. moschata from six regions in 2006. Citrullus vulgaris, Cucumis melo, and C. moschata were infected most frequently; in 76, 60, and 30 of the leaf samples, respectively. CGMMV was tested positive in the samples of 8 seedlings, 23 seeds, and 1 fruit. In contrast, all samples tested negative in 2007. To confirm CGMMV identification, ELISA-positive samples were detected by reverse transcription-PCR assay using virus-specific primers that amplified a 524-bp fragment in the coat protein coding region. The nucleotide sequence of the PCR product (GenBank Accession No. DQ997778) isolated form L. siceraria in Liaoning Province (LHP) showed 100% identity with the Japanese watermelon strain (Japan W) and 91% identity with the Greece GR5 strain. On the basis of the symptoms of indicator plants (chlorotic spot and systemic mosaic were observed in L. siceraria, Chenopodium amaranticolor, and Cucumis sativus; no infection was observed in Datura stramonium, Nicotiana tabacum, and Chenopodium quinoa) and coat protein nucleotide sequence comparisons, the two CGMMV isolates of Wcn (1) and LHP from China should be grouped into the watermelon strain. The results showed that the government should establish effective quarantine strategy and the growers take proper planting measures to avoid further spreading of this virus. References: (1) H. Y. Chen et al. Acta Phytopathol. Sin. 36:306, 2006. (2) B. X. Qin et al. Plant Quarantine. 19:4, 2005.

Quantification of Fusarium graminearum in harvested grain by real-time polymerase chain reaction to assess efficacies of fungicides on fusarium head blight, deoxynivalenol contamination, and yield of winter wheat

We used a real time polymerase chain reaction-based assay and visual disease assessment to evaluate the efficacies of Js399-19, tebuconazole, a mixture of tebuconazole and thiram, azoxystrobin, carbendazim, and thiram on the development of Fusarium head blight (FHB) and deoxynivalenol (DON) contamination and on the yield of winter wheat (cv. Nannong no. 9918) after artificial inoculation under field conditions with Fusarium graminearum. The incidence of infected spikelets (IIS), amount of F. graminearum DNA (Tri5 DNA), total DON (containing DON, 3-acetyl-deoxynivalenol, and 15-acetyl-deoxynivalenol) concentration, and 1,000-grain weight (TGW) were quantified in 2006 and 2007. A strong positive correlation was found between IIS or Log10Tri5 DNA and total DON concentration in the harvested grain. The Js399-19, tebuconazole, and the mixture of tebuconazole and thiram significantly reduced IIS of FHB, amount of Tri5 DNA, and total DON within the grain and increased TGW. Although azoxystrobin, carbendazim, and thiram can increase TGW, they had no effect on the occurrence of F. graminearum compared with those of the untreated controls. Surprisingly, azoxystrobin and carbendazim significantly increased the total DON content in the harvested grain because they might have stimulated the amount of total DON production per Tri5 DNA. The fungicides Js399-19, tebuconazole, and the mixture of tebuconazole and thiram were the most effective in controlling FHB and reducing DON contamination of the wheat.

Syphilis screening and intervention in 500,000 pregnant women in Shenzhen, the People's Republic of China

OBJECTIVES

To understand the disease epidemiology of syphilis in pregnant women, and to evaluate the effectiveness of the screening and intervention programme, for the purpose of controlling mother-to-child syphilis transmission in Shenzhen, in the People's Republic of China (PRC).

METHODS

At the Shenzhen Center for Disease Control and Prevention (SZCDC), we used the toluidine red unheated serum test (TRUST) for the primary screening of pregnant women, and confirmed positive results with the Treponema pallidum particle agglutination (TPPA) test. We informed and treated those with positive results. For the women who chose to proceed with the pregnancy, we clinically screened their babies for congenital syphilis using the 19S-IgM FTA-Abs test.

RESULTS

Between 1 July 2002 and 31 December 2005, we screened 477,656 pregnant women for syphilis, of whom 2208 (0.5%) tested positive. From 2003 to 2005, we collected epidemiological and treatment data from 2019 positive syphilis cases. Of these, 1855 (91.9%) of the pregnant women received treatment. Among the 1020 infants born to these women, 92 (9.0%) were confirmed to have congenital syphilis. If we exclude the mothers who had syphilis positive babies without undergoing prenatal screening, the project's success rate for mother-to-child transmission intervention was 99.1%.

CONCLUSIONS

After four years of implementation, we proved the programme to be successful in preventing mother-to-child syphilis transmission. Further work should be done to ensure the earlier screening and treatment of pregnant women.

Successful application of tissue-engineered skin to refractory ulcers

In this study, the effectiveness of a tissue-engineered skin (Activskin; Aierfu, Xi'an, China) was evaluated for the treatment of various refractory ulcers. These ulcers were treated with Activskin after debridement and irrigation with saline. A second application of Activskin was essential if the first application failed to persist on the wounds. Clinical efficacy and safety were assessed at regular clinic visits during 6 months of follow-up. All 11 treated patients improved with Activskin. The ulcers healed by inward migration from the wound edge. The average healing time was 27.8 days. No recurrent ulceration or other adverse events were observed during follow-up. These results provide preliminary evidence that Activskin is safe and effective in the management of refractory ulcers.