[Predictors of rush popper use among 825 men who have sex with men in education in Guangdong Province]

Objective: To explore prevalence and predictors of the use of Rush poppers among men who have sex with men in education in Guangdong Province. Methods: An internet survey was conducted via a gay website from March to August 2014 and a sample of 833 male respondents over 16 years who had ever had anal sex with a male, studied in Guangdong Province and who had completed an online questionnaire was identified- of which 93.4% (n=825) provided valid responses and were included in the study. Respondents provided information on their socio-demographic characteristics, HIV testing history, sexual activity in last 3 months, Rush poppers use and time since first sexual encounter with a male. We used the Chi-squared test and multivariate logistic regression modeling to identify the predictors of Rush poppers use in this population group. Results: Among our sample of 825 MSM, whose ages ranged from 21-27 years, 14.8% (n=122) reported having used Rush poppers in the past 3 months. Rates of use were higher among those who had ever been tested for HIV (16.7% vs. 10.9%, χ²=4.80, P=0.028), had anal intercourse in the last 3 months (16.8% vs. 10.7%, χ²=5.48, P=0.019), had multiple sexual partners in the past 3 months (19.3% vs. 13.1%, χ²=5.14, P=0.023), had a casual partner (18.0% vs. 12.1%, χ²=5.68, P= 0.017) or had a sexually transmitted infection (23.4% vs. 14.0%, χ²=4.85, P=0.028). Those who reported having had their first sexual encounter with another male over 5 years prior had higher rates of use (18.0%) than for those who had been sexually active ≤1 year (10.7%) or 2-4 years (12.5%, χ²=6.41, P=0.041). HIV testing (OR: 1.70, 95% CI: 1.07-2.70), having a casual partner (OR: 1.67, 95% CI: 1.12-2.50) and being sexually active with other males for over 5 years (OR: 1.87, 95%CI: 1.05-3.31) were significantly associated with Rush poppers use. Conclusion: A large proportion of student MSM in Guangdong Province used Rush poppers. Proxy measures of sexual activity such as HIV testing, recent casual sexual encounters and duration of sexual activity were associated with their use.

[The efficacy and safety of insulin degludec versus insulin glargine in insulin-naive subjects with type 2 diabetes: results of a Chinese cohort from a multinational randomized controlled trial]

Objective: To compare the safety and efficacy of insulin degludec (IDeg) with those of insulin glargine (IGlar) in insulin-naive subjects with type 2 diabetes (T2DM). Methods: This was a 26-week, randomized, open-label, parallel-group, treat-to-target trial in 560 Chinese subjects with T2DM (men/women: 274/263, mean age 56 years, mean diabetes duration 7 years) inadequately controlled on oral antidiabetic drugs (OADs). Subjects were randomized 2∶1 to once-daily IDeg (373 subjects) or IGlar(187 subjects), both in combination with metformin. The primary endpoint was changes from baseline in glycosylated hemoglobin(HbA1c) after 26 weeks. Results: Mean HbA1c decreased from 8.2% in both groups to 6.9% in IDeg and 7.0% in IGlar, respectively. Estimated treatment difference (ETD) of IDeg-IGlar in change from baseline was -0.10% points (95%CI-0.25-0.05). The proportion of subjects achieving HbA1c<7.0% was 56.3%and 49.7% with IDeg and IGlar, respectively [estimated odds ratio of IDeg/IGlar: 1.26(95%CI 0.88-1.82)]. Numerically lower rateof overall confirmed hypoglycaemia and statistically significantly lower nocturnal confirmed hypoglycemia were associated with IDeg compared with IGlar, respectively [estimated rateratio of IDeg/IGlar 0.69(95%CI 0.46-1.03), and 0.43(95%CI 0.19-0.97)]. No differences in other safety parameters were found between the two groups. Conclusions: IDeg was non-inferior to IGlar in terms of glycaemic control, and was associated with a statistically significantly lower rate of nocturnal confirmed hypoglycaemia. IDeg is considered to be suitable for initiating insulin therapy in Chinese T2DM patients on OADs requiring intensified treatment. Clinical trail registration: Clinicaltrials.gov, NCT01849289.

[Application of " Internet Plus" AIDS prevention services among men who have sex with men in Guangzhou, China: results from 2010 to 2015]

Objective: To introduce the development strategy of " Internet Plus" AIDS prevention services and its implementation results from 2010 to 2015 in Guangzhou, China. Methods: A gay men's health column was created for an active website aimed at men who have sex with men(MSM), in collaboration with local community organizations and the Guangzhou CDC. We designed intervention tools(including scenario-based applications and HIV risk self-assessment systems)and an online HIV testing service platform, integrated with applied psychology and behavioral theory as well as the " Internet Plus" concept, to intervene in HIV infection risk factors among MSM. Data of clients who accessed the " Internet Plus" AIDS services from 2010 to 2015 were used to evaluate service operation. Six-year consecutive surveys, conducted between April and July of each service year, were collected using a national AIDS sentinel surveillance questionnaire. For each year of surveillance, information on HIV prevalence, HIV interventions received during the past year, unprotected anal intercourse in the past 6 months, and HIV testing in the past year were compared using the chi-squared(χ²)test, to roughly reflect the effect of"Internet Plus" AIDS prevention services. Results: As of 31 December 2015, a total of 34 395 MSM had received " Internet Plus" services and HIV testing. The number of MSM tested increased from 2 338 in 2010 to 8 054 in 2015. From 2010 to 2015, newly identified HIV cases in each year were 59, 166, 312, 283, 291, and 270, which accounted for 25.0%, 32.8%, 38.8%, 35.1%, 30.5%, and 23.2% of MSM HIV cases of Guangzhou, respectively. Sentinel surveillance data showed that during the study period, 3 047 MSM were investigated, with 405, 400, 401, 633, 608, and 600 each year, respectively. The proportion of participants who had received any HIV intervention during the past year was 74.3%(301), 70.8%(283), 83.3%(334), 85.0%(538), 69.1%(420), and 83.8%(503)each year, respectively(trend χ²=6.53, P=0.011). HIV testing done during the past year accounted for 44.0%(178), 44.3%(177), 49.4%(198), 53.4%(338), 56.1%(341), and 60.2%(361)each year, respectively(trend χ²=40.83, P<0.001). Unprotected anal intercourse in the past 6 months accounted for 59.3%(240), 62.0%(248), 56.6%(227), 57.0%(361), 48.4%(294), and 43.7%(262)each year, respectively(trend χ²=42.21, P<0.001). Conclusion: The"Internet Plus"AIDS prevention services in this study represent a manner to enhance traditional HIV prevention strategies. We found these services to be effective in implementation of the national AIDS control and prevention strategy, especially for the expansion of intervention, testing, and case identification among high-risk populations.

Characterization of the liver X receptor-dependent regulatory mechanism of goat stearoyl-coenzyme A desaturase 1 gene by linoleic acid

Stearoyl-coenzyme A desaturase 1 (SCD1) is a key enzyme in the biosynthesis of palmitoleic and oleic acid. Although the transcriptional regulatory mechanism of SCD1 via polyunsaturated fatty acids (PUFA) has been extensively explored in nonruminants, the existence of such mechanism in ruminant mammary gland remains unknown. In this study, we used goat genomic DNA to clone and sequence a 1,713-bp fragment of the SCD1 5' flanking region. Deletion assays revealed a core region of the promoter located between -415 and -109 bp upstream of the transcription start site, and contained the highly conserved PUFA response region. An intact PUFA response region was required for the basal transcriptional activity of SCD1. Linoleic acid reduced endogenous expression of SCD1 and sterol regulatory element binding factor-1 (SREBF1) in goat mammary epithelial cells. Further analysis indicated that both the sterol response element (SRE) and the nuclear factor Y (NF-Y) binding site in the SCD1 promoter were responsible for the inhibition effect by linoleic acid, whereas the effect was abrogated once NF-Y was deleted. In addition, SRE and NF-Y were partly responsible for the transcriptional activation induced via the liver X receptor agonist T 4506585 (Sigma-Aldrich, St. Louis, MO). When goat mammary epithelial cells were cultured with linoleic acid, addition of T 4506585 markedly increased SCD1 transcription in controls, but had no effect on cells with a deleted SRE promoter. These results demonstrated that linoleic acid can regulate SCD1 expression at the transcriptional level through SRE and NF-Y in a liver X receptor-dependent fashion in the goat mammary gland.

Liver X receptor α promotes the synthesis of monounsaturated fatty acids in goat mammary epithelial cells via the control of stearoyl-coenzyme A desaturase 1 in an SREBP-1-dependent manner

Stearoyl-coenzyme A desaturase 1 (SCD1) is a pivotal enzyme in the biosynthesis of monounsaturated fatty acids (MUFA). It is tightly regulated by transcription factors that control lipogenesis. In nonruminants, liver X receptor α (LXRα) is a nuclear receptor and transcription factor that acts as a key sensor of cholesterol and lipid homeostasis. However, the mechanism whereby LXRα regulates the expression and transcriptional activity of SCD1 in ruminant mammary cells remains unknown. In this study with goat mammary epithelial cells (GMEC), the LXRα agonist T 4506585 (T09) markedly enhanced the mRNA expression of SCD1 and sterol regulatory element binding factor 1 (SREBF1). The concentrations of C16:1 and C18:1 and their desaturation indices also were increased by LXRα activation. However, knockdown of LXRα did not alter the mRNA expression of SCD1. Although SCD1 was repressed by SREBF1 knockdown, T09 significantly increased SCD1 expression. Further analysis revealed that the SCD1 promoter activity was activated by LXRα overexpression. The goat SCD1 promoter contains 2 LXR response elements (LXRE), 1 sterol response element (SRE), and 1 nuclear factor Y (NF-Y) binding site. Site-directed mutagenesis of LXRE1, LXRE2, or SRE alone did not eliminate the upregulation of SCD1 when LXRα was overexpressed. In contrast, when NF-Y alone or in combination with SRE was mutated simultaneously, the basal transcriptional activity of the SCD1 promoter was markedly decreased and did not respond to LXRα overexpression. Furthermore, when SREBF1 was knocked down, overexpression of LXRα did not affect the promoter activity of SCD1. Together, these data suggest that LXRα regulates the expression of SCD1 through increasing SREBP-1 abundance to promote interaction with SRE and NF-Y binding sites. The present study provides evidence that LXRα is involved in the synthesis of MUFA in the goat mammary gland through an indirect mechanism.

Short communication: Altered expression of specificity protein 1 impairs milk fat synthesis in goat mammary epithelial cells

Specificity protein 1 (encoded by SP1) is a novel transcription factor important for the regulation of lipid metabolism and the normal function of various hormones in model organisms. Its potential role, if any, on ruminant milk fat is unknown. Despite the lower expression of the lipolysis-related gene ATGL (by 44 and 37% respectively), both the adenoviral overexpression and the silencing of SP1 [via short interfering (si)RNA] markedly reduced cellular triacylglycerol (TAG) content (by 28 and 25%, respectively), at least in part by decreasing the expression of DGAT1 (-36% in adenovirus treatment) and DGAT2 (-81 and -87%, respectively) that are involved in TAG synthesis. Consistent with the markedly lower expression of genes related to lipid droplet formation and secretion (TIP47 by 19 and 32%, and ADFP by 25 and 25%, respectively), cellular lipid droplet content was also decreased sharply, by 9 and 8.5%, respectively, after adenoviral overexpression of SP1 or its silencing via siRNA. Overall, the results underscored a potentially important role of SP1 in maintaining milk-fat droplet synthesis in goat mammary epithelial cells.

Thyroid hormone responsive (THRSP) promotes the synthesis of medium-chain fatty acids in goat mammary epithelial cells

In nonruminants, thyroid hormone responsive (THRSP) is a crucial protein for cellular de novo lipogenesis. However, the role of THRSP in regulating the synthesis of milk fatty acid composition in goat mammary gland remains unknown. In the present study, we compared gene expression of THRSP among different goat tissues. Results revealed that THRSP had the highest expression in subcutaneous fat, and expression was higher during lactation compared with the dry period. Overexpression of THRSP upregulated the expression of fatty acid synthase (FASN), stearoyl-coenzyme A desaturase 1 (SCD1), diacylglycerol acyltransferase 2 (DGAT2), and glycerol-3-phosphate acyltransferase (GPAM) in goat mammary epithelial cells. In contrast, overexpression of THRSP led to downregulation of thrombospondin receptor (CD36) and had no effect on the expression of acetyl-coenzyme A carboxylase α (ACACA) and sterol regulatory element binding transcription factor1 (SREBF1). In addition, overexpressing THRSP in vitro resulted in a significant increase in triacylglycerol (TAG) concentration and the concentrations of C12:0 and C14:0. Taken together, these results highlight an important role of THRSP in regulating lipogenesis in goat mammary epithelial cells.

Calorimetric Studies on Thermal Properties of Nano-Cryoprotectant Solutions during Vitrification

BACKGROUND: Vitrification, the ice-free cryopreservation, develops rapidly and can become an ideal method for long-term preservation of cells and tissues. But up to now it is not practical for samples with large size because of the ultra-rapid cooling rate required. It has been reported that nanoparticles improve heat conductivity of solutions.

MATERIALS AND METHODS

In this study, Hydroxyapatite (HA) nanoparticles（20, 40 or 60nm）at 0.1 %, 0.5 % or 1 % (w/w) were added into glycerol solutions. Glass transition temperature and devitrification temperature of aqueous glycerol solutions with/without HA nanoparticles were measured by a differential scanning calorimeter(DSC) at a cooling rate of 150 degree C/min and a warming rate of 10 degree C/ min.

RESULTS AND CONCLUSION

Glass-transition temperatures and devitrification temperatures of glycerol aqueous solutions increased after the incorporation of HA nanoparticles. In the study using slow cooling rate of 10 degree C/min and warming rate of 5 degree C/min, the fraction of unfrozen water in the 50 % (w/w) glycerol solution increases steadily with the addition of HA nanoparticles. The findings have significant implications for biomaterial cryopreservation.

Prognostic role of microRNA-100 in patients with bladder cancer

We investigated the clinical significance and prognostic value of microRNA-100 (miR-100) in bladder cancer. Quantitative real-time polymerase chain reaction was used to analyze the expression of miR-100 in 92 pairs of human bladder cancer and adjacent normal tissue samples. Overall survival (OS) curves were plotted using the Kaplan-Meier method and were evaluated for statistical significance using a log-rank test. The significance of different variables with respect to survival was analyzed using the multivariate Cox proportional hazard model. The miR-100 expression level was significantly lower in bladder cancer tissues than in normal adjacent tissues (mean ± SD: 1.49 ± 0.52 vs 2.79 ± 0.59, P < 0.05). A low miR-100 expression level was correlated with tumor stage (P = 0.023), tumor grade (P = 0.031), and regional lymph node involvement (P = 0.16). Kaplan-Meier analysis with log-rank test indicated that low miR-100 expression had a significant impact on OS (35.1 vs 75.3%; P = 0.004). Multivariate analysis revealed that the miR-100 expression level was an independent prognostic factor for OS (HR = 2.768, 95%CI = 1.287-8.992; P = 0.009) in bladder cancer patients. The present study demonstrated that the downregulation of miR-100 was associated with advanced clinical features and poor prognosis for bladder cancer patients, suggesting that miR-100 downregulation may be used as an unfavorable prognostic biomarker in bladder cancer.

MicroRNA-24 can control triacylglycerol synthesis in goat mammary epithelial cells by targeting the fatty acid synthase gene

In nonruminants it has been demonstrated that microRNA-24 (miR-24) is involved in preadipocyte differentiation, hepatic lipid, and plasma triacylglycerol synthesis. However, its role in ruminant mammary gland remains unclear. In this study we measured miR-24 expression in goat mammary gland tissue at 4 different stages of lactation and observed that it had highest expression at peak lactation when compared with the dry period. Overexpression or downregulation of miR-24 in goat mammary epithelial cells (GMEC) strongly affected fatty acid profiles; in particular, miR-24 enhanced unsaturated fatty acid concentration. Additional effects of miR-24 included changes in triacylglycerol content and the expression of fatty acid synthase, sterol regulatory element binding transcription protein 1, stearoyl-CoA desaturase, glycerol-3-phosphate acyltransferase mitochondrial, and acetyl-CoA carboxylase. Luciferase reporter assay confirmed that fatty acid synthase is a target of miR-24. Taken together, these results not only highlight the physiological importance of miR-24 in fatty acid metabolism in GMEC, but also laid the foundation for further research on regulatory mechanisms among miR-24 and other microRNA expressed in GMEC.

Adipocyte differentiation-related protein promotes lipid accumulation in goat mammary epithelial cells

Milk fat originates from the secretion of cytosolic lipid droplets (CLD) synthesized within mammary epithelial cells. Adipocyte differentiation-related protein (ADRP; gene symbol PLIN2) is a CLD-binding protein that is crucial for synthesis of mature CLD. Our hypothesis was that ADRP regulates CLD production and metabolism in goat mammary epithelial cells (GMEC) and thus plays a role in determining milk fat content. To understand the role of ADRP in ruminant milk fat metabolism, ADRP (PLIN2) was overexpressed or knocked down in GMEC using an adenovirus system. Immunocytochemical staining revealed that ADRP localized to the surface of CLD. Supplementation with oleic acid (OA) enhanced its colocalization with CLD surface and enhanced lipid accumulation. Overexpression of ADRP increased lipid accumulation and the concentration of triacylglycerol in GMEC. In contrast, morphological examination revealed that knockdown of ADRP decreased lipid accumulation even when OA was supplemented. This response was confirmed by the reduction in mass of cellular TG when ADRP was knocked down. The fact that knockdown of ADRP did not completely eliminate lipid accumulation at a morphological level in GMEC without OA suggests that some other compensatory factors may also aid in the process of CLD formation. The ADRP reversed the decrease of CLD accumulation induced by adipose triglyceride lipase. This is highly suggestive of ADRP promoting triacylglycerol stability within CLD by preventing access to adipose triglyceride lipase. Collectively, these data provide direct in vitro evidence that ADRP plays a key role in CLD formation and stability in GMEC.

Left ventricular posterior wall thickness is an independent risk factor for paroxysmal atrial fibrillation

BACKGROUND

Atrial fibrillation is the most common significant cardiac arrhythmia in clinical practice, but its risk factors remain to be clarified. We have hypothesized that left ventricular posterior wall thickness is an independent risk factor for paroxysmal atrial fibrillation (PAF).

METHODS

A total of 166 consecutive patients with paroxysmal atrial fibrillation were included in this study. Another 166 healthy check-up people, strictly age and sex-matched, were enrolled as controls in the same period. Univariable analysis and multivariable conditional logistic stepwise regression analysis were conducted. Receiver operating characteristic (ROC) curve analysis was performed on those significant indices obtained from the multivariable logistic regression analysis.

RESULTS

The multivariable stepwise analysis identified left ventricular posterior wall thickness, left atrial diameter tricuspid insufficiency and residence (countryside) as independent predictors for paroxysmal atrial fibrillation. Receiver operating characteristic curve analysis demonstrated the cutoff values of those risk factors aforementioned.

CONCLUSIONS

In this strictly age and sex-matched population-based sample, left ventricular posterior wall thickness, left atrial diameter, tricuspid insufficiency and residence were predictive risks for paroxysmal atrial fibrillation. This study offers novel information therapeutically beyond that provided by traditional clinical atrial fibrillation risk factors.

An experimental and quasiclassical trajectory study of the rovibrationally state-selected reactions: HD+(v=0–15,j=1)+He→HeH+(HeD+)+D(H)

The absolute integral cross sections for the formation of HeH+ and HeD+ from the collisions of HD+(v,j=1)+He have been examined over a broad range of vibrational energy levels v=0-13 at the center-of-mass collision energies (ET) of 0.6 and 1.4 eV using the vacuum ultraviolet (VUV) pulsed field ionization photoelectron secondary ion coincidence method. The ET dependencies of the integral cross sections for products HeH+ and HeD+ from HD+(v=0-4)+He collisions in the ET range of 0-3 eV have also been measured using the VUV photoionization guided ion beam mass spectrometric technique, in which vibrationally selected HD+(v) reactant ions were prepared via excitation of selected autoionization resonances of HD. At low total energies, a pronounced isotope effect is observed in absolute integral cross sections for the HeH++D and HeD++H channels with significant favoring of the deuteron transfer channel. As v is increased in the range of v=0-9, the integral cross sections of the HeH++D channel are found to approach those of HeD++H. The observed velocity distributions of products HeD+ and HeH+ are consistent with an impulsive or spectator-stripping mechanism. Detailed quasiclassical trajectory (QCT) calculations are also presented for HD+(v,j=1)+He collisions at the same energies of the experiment. The QCT calculations were performed on the most accurate ab initio potential energy surface available. If the zero-point energy of the reaction products is taken into account, the QCT cross sections for products HeH+ and HeD+ from HD+(v)+He are found to be significantly lower than the experimental results at ET values near the reaction thresholds. The agreement between the experimental and QCT cross sections improves with translational energy. Except for prethreshold reactivity, QCT calculations ignoring the zero-point energy in the products are generally in good agreement with experimental absolute cross sections. The experimental HeH+/HeD+ branching ratios for the HD+(v=0-9)+He collisions are generally consistent with QCT predictions. The observed isotope effects can be rationalized on the basis of differences in thermochemical thresholds and angular momentum conservation constraints.

[Molecular cloning, sequence and function analyses and specific expression of gene BmICAD related to apoptosis in silkworm, Bombyx mori]

The DREP-1 gene plays an important role in the process of apoptosis in Drosophila. The amino acid sequence of Drosophila ICAD was searched against the silkworm EST database. The resulted ESTs were clustered and assembled into a consensus sequence. Primers based on the consensus sequence were designed and the full length cDNA of ICAD gene, designated BmICAD, was cloned firstly from Bombyx mori. This BmICAD cDNA was 844-bp in length, containing a 522-bp open reading frame (ORF), which encoded a protein of 174 amino acids; the molecular weight of this protein was estimated to be 19.6 kDa and the isoelectric point was 4.23. The BmICAD protein shares 36% identity with Drosophila DREP-1. No signal has inspected by Northern blot, but RT-PCR analysis showed that BmICAD was testis-specific expressed at the mRNA level. Structure and clustering analysis indicated that this gene might be involved in the process of apoptosis that regulate the degradation of DNA.

Identification and characterization of piggyBac-like elements in the genome of domesticated silkworm, Bombyx mori

piggyBac is a short inverted terminal repeat (ITR) transposable element originally discovered in Trichoplusia ni. It is currently the preferred vector of choice for enhancer trapping, gene discovery and identifying gene function in insects and mammals. Many piggyBac-like sequences have been found in the genomes of phylogenetically species from fungi to mammals. We have identified 98 piggyBac-like sequences (BmPBLE1-98) from the genome data of domesticated silkworm (Bombyx mori) and 17 fragments from expressed sequence tags (ESTs). Most of the BmPBLE1-98 probably exist as fossils. A total of 21 BmPBLEs are flanked by ITRs and TTAA host dinucleotides, of which 5 contain a single ORF, implying that they may still be active. Interestingly, 16 BmPBLEs have CAC/GTG not CCC/GGG as the characteristic residues of ITRs, which is a surprising phenomenon first observed in the piggyBac families. Phylogenetic analysis indicates that many BmPBLEs have a close relation to mammals, especially to Homo sapiens, only a few being grouped with the T. ni piggyBac element. In addition, horizontal transfer was probably involved in the evolution of the piggyBac-like elements between B. mori and Daphnia pulicaria. The analysis of the BmPBLEs will contribute to our understanding of the characteristic of the piggyBac family and application of piggyBac in a wide range of insect species.

EST-based profiling and comparison of gene expression in the silkworm fat body during metamorphosis

The fat body plays key roles in metabolism and sustenance of growth throughout the life of a silkworm, and thus represents a model tissue for studying development and metamorphosis. Analysis of 18,480 ESTs derived from larval and pupal fat body cDNA libraries allowed characterization of gene expression patterns in the fat body during metamorphosis. By Phrap assembling, 6,814 estimated transcription units (TUs) were generated, 2,673 of which contained 60% of the total ESTs and represented 1,366 distinctive known genes. These genes were classified into 14 categories based on their known or putative functions, and most were found to be involved in metabolism and cell defense. Further comparative analysis of the expression profiles revealed that the gene expression patterns in the larval fat body strikingly differed from those in the pupal fat body. From this, we identified a subset of genes potentially associated with metamorphic events such as the formation or destruction of specific tissues, and simultaneously confirmed the stage-specific expression patterns of several identified genes using RT-PCR examination. This work will provide a valuable resource for studying regulatory mechanisms associated with fat body developmental changes and silkworm metamorphosis.

[Three Bombyx mori genes, chi, gluE and fruA, encode proteins homologous to microorganism and primary analysis of horizontal gene transfer]

According to the analysis of large scale EST sequencing of silkworm, Bombyx mori, we found that chi, glue and fruA of silkworm have very high homology at amino acid level and closely phylogenetic relative with that of microorganism, but lower similarity with genes of eelworm (Caenorhabditis elegans), fruitfly (Drosophila melanogaster), mosquito (Anopheles gambiae) and other relative insects, respectively. It indicates that each of them is likely to have common ancestor with that of microorganism. Namely, microbial genes were likely transferred to silkworm by horizontal gene transfer, instead of the vertical inheritance in evolutionary manner.

[Purification of follicle-stimulating hormone by radial-flow chromatography]

By comparing the purification results of radial-flow chromatography with conventional chromatography, a new purification process of follicle-stimulating hormone (FSH) from crude sample of human menopausal gonadotrophin has been developed. The results showed that the specific activity, activity recovery, and purification factor of FSH purified by radial-flow chromatography were higher than those by conventional chromatography in large scale. The specific activity of FSH purified was 180 IU/mg protein, activity recovery 56%, purification factor 150. The purified product meets the quality requirement of the Standard of Chinese Pharmacopoeia.

Long-term efficacy of active postexposure immunization of infants for prevention of hepatitis B virus infection. United States-People's Republic of China Study Group on Hepatitis B

Perinatal transmission of hepatitis B virus (HBV) contributes to the high prevalence of chronic infection in China and many other countries. In a placebo-controlled trial among 166 infants, the 12-month efficacy of active postexposure prophylaxis to prevent chronic perinatal HBV infection varied by vaccine (range, 45%-89%). In a 5-year follow-up study, 2 additional infants became chronically infected with HBV, and the efficacy of active prophylaxis was estimated to be 38% and 72% for the two vaccines at 5 years. In addition, 80% of immunized infants continued to have protective levels of antibody at the end of 5 years. However, among 27 infants who received passive-active immunoprophylaxis with high-dose hepatitis B immune globulin, only 60% (11/19) had protective antibody levels. These data indicate that active postexposure immunization initiated soon after birth continues to provide protection during early childhood when there is a high risk of chronic HBV infection.

Mechanism of refractive-index change in a Ce:SBN single crystal illuminated by nominal homogeneous light

We report a series of experiments demonstrating that the refractive index n(e) of a single crystal of Ce:SBN increases when the crystal is illuminated by a nominal homogeneous Ar laser beam. The increase is larger than that owing to the pure temperature rise, which is equal to that occurring in a Ce:SBN crystal illuminated by the same laser beam. We discovered that the difference between these Deltan(e)'s owing to the light and to the heat caused by this light is closely related to the crystal's history of illumination; the more it is illuminated, the less the difference is. Also, when the illumination exceeds the threshold volume for the first time, the refractive index will increase to be linear. We believe this to be the first report of these phenomena; we have introduced a theoretical explanation.

Long-term immunogenicity and efficacy of recombinant yeast derived hepatitis B vaccine for interruption of mother-infant transmission of hepatitis B virus

Recombinant DNA Yeast-Derived Hepatitis B Vaccine (RYHB vaccine) is comparable to and can replace Plasma-Derived Hepatitis B Vaccine (PHB vaccine) for the prevention of mother-infant transmission of hepatitis B virus (HBV), but the duration of immune efficacy of RYHB vaccine is not clear. This study indicates the long-term efficacy for the prevention of mother-infant transmission of HBV. One hundred and six neonates born to HBsAg-carrier mothers with HBeAg positive were randomly divided into two groups, one receiving 20 micrograms per dose of RYHB vaccine and the another receiving 20 micrograms per dose of PHB vaccine on the day of birth, at 1 month and at 6 months (three times). Physical examination and blood tests were performed for all infants at 6, 12, 24, 36, 48 and 60 months of age. The results showed that the protective efficacies at 6, 12, 24, 36, 48 and 60 months were 67%, 75%, 63%, 62%, 57% and 56%, respectively for the RYHB vaccine group and 58%, 76%, 51%, 41%, 24% and 18%, respectively for the PHB vaccine group. The protective efficacy was notably significant in the last two years. The study indicates that the duration of protective efficacy is over 5 years with RYHB vaccine, being longer than that of PHB vaccine. These recipients of RYHB vaccine showed no side effects, and the vaccine is regarded as safe and effective.

[Preparation and antigenic characterization of rat monoclonal antibodies against hemorrhagic fever with renal syndrome virus]

11 hybridoma cell lines secreting monoclonal antibodies (McAbs) against hemorrhagic fever with renal syndrome virus (HFRSV) were obtained in our laboratory by immunizing LOU/C rats with HFRSV Chen strain. These rat McAbs were characterized by radio-immunoprecipitation and western blotting methods, 2 directed against glycoprotein G2, 9 against nucleocapsid protein (NP) of HFRSV. The results of neutralization (NT) and hemagglutination inhibition(HI) test showed that most of the McAbs specific for NP had neither NT nor HI activities, but 2 had obvious NT and/or HI activities. It was suggested that there may be some neutralizing and hemagglutinating determinants on NP of HFRSV. Two McAbs to G2 had HI or/and NT activities. These date indicated that distinct neutralizing and hemagglutinating epitopes were located on the G2. Comparative antigenic analysis of 20 strains of HFRSV was carried out by immune horseradish peroxidase technique using 11 anti-HFRSV rat McAbs. It was found that these McAbs can be classified into group, subgroup, apodemus type and subtype specificity to HFRSV.

A six-year survey of immunogenicity and efficacy of hepatitis B vaccine in infants born to HBsAg carriers

Although the efficacy of hepatitis B vaccine is well documented, the duration of immunity of healthy infants after vaccination is unknown. 99 infants born to hepatitis B surface antigen (HBsAg)-carrier mothers were studied and found to have positive anti-HBs (titer: greater than or equal to 10 mIU/mL) after a first injection of vaccine at the ages of 1 to 6 years. The infants were randomly divided into four groups of recipients treated with the vaccine of the National Institute of Allergy and Infectious Diseases (NIAID), U.S.A. or that of the Beijing Biological Products Research Institute (BBPRI), BBPRI vaccine in combination with hepatitis B immune globulin (HBIG) and placebo. The results showed that the protective efficacy dropped considerably after 5 years with NIAID vaccine, after 3 years with BBPRI vaccine and after 4 years with BBPRI vaccine plus HBIG. This suggests that a booster injection is needed 5 years after the first injection of NIAID vaccine, 3 years after BBPRI vaccine, and 4 years after BBPRI vaccine plus HBIG.