Search

SUMMARYLongan County is considered a highly endemic area for hepatitis B virus (HBV). The plasma-derived vaccine has been used in newborns in this area since 1987. A cross-sectional survey was conducted to evaluate the long-term effectiveness of this vaccine. In total, 1634 participants born during 1987–1993 and who had received a series of plasma-derived HB vaccinations at ages 0, 1, and 6 months were enrolled. Serological HBV markers were detected and compared with previous survey data. Overall the prevalence of hepatitis B surface antigen (HBsAg) in all participants was 3·79%; 3·47% of subjects who had received the first dose within 24 h were HBsAg positive, and 8·41% of subjects who had received a delayed first dose were also HBsAg positive. There were 1527 subjects identified who had received the first dose within 24 h and whose HBsAg and anti-HBc prevalence increased yearly after immunization, while the anti-HBs-positive rate and vaccine effectiveness declined. The geometric mean concentration of antibody in the anti-HB-positive participants was 55·13 mIU/ml and this declined after immunization. Fewer than 2·0% of participants had anti-HB levels ⩾1000 mIU/ml. The data show that the protective efficacy of the plasma-derived vaccinations declined and administration of HB vaccine within 24 h of birth was very important. To reduce the risk of HBV infection in this highly endemic area, a booster dose might be necessary if anti-HBs levels fall below 10 mIU/ml after age 18 years. Furthermore, studies on the immune memory induced by plasma-derived HB vaccine are needed.

To evaluate the hepatitis A vaccine coverage among 2-29 year olds and the reported incidence rates of hepatitis A, in China.Based on data from the national sero-survey on hepatitis B in 2014, information on hepatitis A vaccine immunization was collected and the coverage of hepatitis A vaccine was analyzed with SAS software (Version 9.4). Incidence data on hepatitis A was also collected from the National Notifiable Disease Reporting System between 2004 and 2014, and analyzed using the micro-software Excel 2007.Totally, data involving 29 058 people aged 2-29 years were available for analysis and the overall hepatitis A vaccine coverage was 44.6%. The younger the age, the higher the coverage appeared. Among the 2-6 year and the 7-14 year olds, rates of hepatitis A vaccine coverage were 91.2% and 76.0% respectively. From 2004 to 2014, the incidence rates of hepatitis A in the whole population were declining, annually. The incidence rates showed continuously declining as 82.5%, 90.6%, 72.1% among children at the age groups of 2-6 years, 7-14 years and in the whole population, from 2007 to 2013.After the inclusion of hepatitis A vaccine into the Expanded Programe on Immunization (EPI), the coverage of hepatitis A vaccine among the 2-6 year olds increased to over 90%, with no obvious difference between the urban and rural areas. Incidence of hepatitis A in the 2-6 year olds showed a more rapid decline than that in the whole population.

A sensitive air-flow sensor element was constructed, using an arched CoSiB magnetostrictive amorphous wire connected to a straight hair-type amorphous wire. A sharp pulse current is applied through the arched wire to generate the stress-impedance (SI) effect with a strong skin effect. The resolution for air flow detection is about 0.16 m/s, which is almost the same as that of conventional heated resistance wire-type air-flow sensors. The amorphous wire air-flow sensor element is suitable for adding an air-flow-sensing ability to intelligent robots.

A time series reflecting human brain activities was detected by using a sensitive micro-acceleration · inclined-angle sensor composed of a CoSiB magnetostrictive amorphous wire connected to a CMOS IC circuit with a resolution of about 0.1 Gal and 0.2°. A small sensor head using a glass specimen of 0.16 mm thick, 3 mm wide, and 15 mm long to which were attached a CoSiB amorphous wire of 20 μm diameter and 5 mm length and an inertia mass of 0.1 g was fixed to the center of a subject’s forehead.The detected waveforms of the sensor output for subjects with both eyelids closed differ from the microvibration would be classified into the following four kinds of states:(1) An almost flat waveform indicates that the subject is in a resting state or a sleeping state.(2) Passively stressful states such as recalling sad memories, being obliged to perform an unpleasant task, or performing a mental calculation generate a large stepwise wave with some irregular pulsing waves.(3) Actively stressful states such as finding a good idea and focusing on inventing something are indicated by high-frequency pulsing waves.(4) Pleasant states such as recalling happy memories of childhood or thinking about a favorite hobby are indicated by rhythmical waves without pulses.These signals reflecting a subject’s mental and emotional states (which we call a mechano-encephalogram) are considered to be due to micro-deformation and acceleration of the measurement position with some movement of eyeball muscles, arrector pili muscles and muscles corrugator supercilii. Microvibrations of small amplitude were also detected.

A sensitive twisting stress-impedance effect in a CoSiB amorphous wire (λ= -3 × 10-6, 20 μm diameter, 10 mm length) is presented. The impedance in the wire changes by more than 50% for a twisting angle of ± 180°(1/2 turn). The impedance change occurs with the skin effect in the wire, and its twisting characteristic depends on the wire current frequency. The mechanisms of the twisting stress-impedance effect is analyzed, taking account of BH hysteresis loops in the wire’s circumferential flux path and a magnetization rotation model.

A highly sensitive linear strain gauge using a pair of amorphous CoSiB wires fixed to a plastic cantilever beam combined with a CMOS IC multivibrator circuit is presented. The wires are magnetized with a sharp pulse current to generate the stress impedance (SI) effect, showing a gauge factor of about 2000 in the CMOS IC circuit The linear strain gauge shows a resolution of about 2.5 mg for weight detection with high linearity in the range of −0.75∼1.25 g. The mechanism of the SI characteristics in the CoSiB wire is analyzed using a magnetization rotation model. Pulsation of fingertip blood vessels was stably detected by using the SI gauge stress sensor.

Quantification of cytomegalovirus (CMV) DNA in blood may aid in the identification of patients at highest risk for developing CMV disease, the evaluation of new therapeutics, and the prompt recognition of drug-resistant CMV strains. A branched-DNA (bDNA) assay was developed for the reliable quantification of CMV DNA in peripheral blood leukocytes. The bDNA assay allowed for the highly specific and reproducible quantification of CMV DNA in clinical specimens. Furthermore, the bDNA assay was at least as sensitive as culture techniques and displayed a nearly 3 log10 dynamic range in quantification. Changes in CMV DNA levels measured by the bDNA assay in a human immunodeficiency virus-positive patient undergoing therapy were consistent with CMV culture, antigen, and genotype results and correlated with disease progression and resistance markers. The bDNA assay for the quantification of CMV DNA may provide a useful tool that can be used to aid physicians in monitoring disease progression, evaluating therapeutic regimens, and recognizing viral resistance and drug failure.

Two cDNAs were cloned that encode proteins (Pan-1 and Pan-2, with predicted molecular masses of 67.4 and 67.7 kD, respectively) that bind to a conserved transcriptional regulatory element present in pancreatic exocrine genes. The cDNAs are virtually identical in the region that encodes the amino-terminal 525 amino acids; they differ only by a 3-nucleotide insertion that results in the addition of a single amino acid. The cDNAs, however, code for related, but divergent, carboxy-terminal regions. Expression of the cloned cDNAs in HeLa cells activates expression of a cotransfected chimeric gene containing multimers of the pancreatic conserved element linked to a minimal promoter. Pan-1 and Pan-2 bind to the consensus sequence CAC/GCTGT/C, the CACCTGTC motif, which is present in transcriptional control elements of several genes. Both Pan-1 and Pan-2 bind to related motifs present in the rat insulin enhancer as well as a DNA segment containing the SV40 AP-4 element. The Pan-1 and Pan-2 cDNAs display extensive sequence identity with partial cDNA clones encoding E12 and E47, which bind to the immunoglobulin kappa E2 cis-active element, and may be derived from the same gene. These factors belong to a set of genetically distinct molecules, including AP-4 and MLTF, that bind to the CACCTGTC motif or related sequences. The Pan/E12,E47 proteins also show structural similarity with the Drosophila daughterless protein, MyoD, Myogenin, and Myf-5.

Sensitive, quick response and low power consumption micro-magnetic sensors have been developed utilizing the magneto-impedance (MI) and stress-impedance (SI) effects in zero-magnetostrictive (zero-/spl lambda/) and negative-magnetostrictive amorphous wires connected with CMOSFET IC sensor circuits. The MI magnetic field sensor using zero-/spl lambda/ amorphous wires of 30 /spl mu/m diameter and 2 mm length represents the resolution of about 1 /spl mu/G for AC fields and about 100 /spl mu/G for the DC field with /spl plusmn/3 G in the full scale, the cut-off frequency of about 1 MHz, and low power consumption of about 10 mW for the CMOS MI sensor. The SI sensor using a 20 /spl mu/m diameter negative-/spl lambda/ amorphous wire shows the gauge factor of about 4000 for stress (strain) sensors and the resolution of 0.1 Gal for acceleration sensors. The principles, basic features, and applications of MI and SI sensors are summarized.

Objective. To investigate the development method of porous plate, the key part of water sublimator, and its main physical characteristics. Method. Technical parameters of porous plates used in water sublimator were analyzed. On the basis of this, porous plates made of different materials were developed by making use of sintered powder technology. A tester for testing the physical characteristics of porous plate was designed. All around physical characteristic tests for porous plates were conducted. Result. Main factors affecting performance of porous plates were tested. These provided basis for performance test of sublimator, established porous plate criterion and optimized porous plate. Conclusion. Porous plates developed by making use of sintered powder technology could meet requirements of performance of water sublimator.

New research progress of thermal control system for oversea Extravehicular Activity (EVA) space suit is presented. Characteristics of several thermal control systems are analyzed in detail. Some research tendencies and problems are discussed, which are worthwhile to be specially noted. Finally, author's opinion about thermal control system in the future is put forward.

Mouse-Chinese hamster hybrids segregating mouse chromosomes were analyzed by Southern hybridization techniques to map the genes for somatostatin (Smst), glucagon (Gcg), calcitonin (Calc) and parathyroid hormone (Pth). The mouse gene for somatostatin, detected on a 20-kb EcoRl fragment, is located on mouse chromosome 16. Glucagon cDNA hybridized to a 14-kb EcoRl fragment residing on chromosome 2. Calcitonin and parathyroid hormone genes, detected on 7.8-kb HindIII and 6.0-kb BamHI fragments, respectively, were on mouse chromosome 7. The calcitonin and parathyroid hormone genes appear to be part of a larger linkage group which has been conserved in mouse and man.

The surface antigen gene of HBV (adr subtype) is inserted into the YEP 1 which is replicated and selected in E. coli and baker yeast Saccharomyces cerevisiae. The HBsAg gene can be expressed in yeast under GAL-10 promoter control. The protein synthesized in yeast is assembled into particles that have the same size and shape as particles isolated from plasma. One microgram surface antigen can be yielded in 100 ml culture.

Hepatitis B surface antigen (HBsAg, an exogenous protein) was produced by fermenting recombinant Saccharomyces cerevisiae containing the HBsAg gene. The relative HBsAg concentrations increased from 3.89 to 8.12 when glucose content was reduced and the culture medium was supplemented with glycerol and sucrose; specific activity also increased by a factor of 2.69. The temperature variation sequence for fermentation processes was established from experimental results. The amount of HBsAg gene expressed reached 13.51 in relative concentration terms. The stability of the recombinant plasmid containing the HBsAg gene was studied by the varying fermentation temperatures in a fed-batch process. There was a conversion activity distribution for the yeast containing the exogenous DNA, which affected HBsAg production by the genetically engineered yeast in fermentation processes.

The nucleotide sequence of the XhoI-BamHI fragment (1279bp), which contains the surface antigen gene (S gene) of HBVadr, was determined by Maxam and Gilbert's method. By comparing the differences both of the nucleotide sequence in the S gene and its coded amino acid sequence between adr and those reported for adw, ayw and adyw, some new variation sites were discovered. The differences were mainly distributed in the two hydrophilic regions. However, at those sites which might show biological function, there were no variations among different subtypes, they are relatively conservative in heredity and evolution. Comparing the variation of the nucleotide sequence in the S gene region with that in the non-S gene region, it is shown that the frequency of variation in the non-S gene region doubled that in the S gene region. The S gene region is more conservative.

The complete nucleotide sequence of the cloned hepatitis B virus DNA subtype adr in pADR-1 was determined by Maxam and Gilbert's method. It is 3215 base pairs in size, which is 27 bp longer than the sequence of the adr pHBr330, as reported by Ono et al. The nucleotide difference between pADR-1 and adr pHBr330 is about 2% while those between pADR-1 and adw as well as ayw are 9.3% and 9.7% respectively. In this paper, the heterogeneity and homogeneity of the S gene, the C gene and the other coding regions in pADR-1 and in the other subtypes are compared and discussed.

Both cell growth and expression of hepatitis B surface antigen (HBsAg) interact with each other in fermentation to produce exogenous protein HBsAg by genetically engineered yeast, S. cerevisiae, which contains the HBsAg gene. Since both processes required proper pH values in order to improve the overall yield, a suitable pH value sequence was determined. It is important that dissolved oxygen concentration in fermentation should be controlled to maintain the stability of recombinant plasmids and to obtain the high HBsAg expression. When the concentration of dissolved oxygen was controlled at 70% saturation, the stability of recombinant plasmid was maintained at 73%, and the relative concentration of HBsAg expression was found to be 98.6.