[Evaluation of intervention effect in the occupational protection of glass fiber workers by occupational health education]

Objective: To understand the mastery of occupational hygienic knowledge and the implementing of occupational health protection measures in the group which were exposed to the procedure of manufacture and use in glass fiber company, and to explore the feasibility of the prevention of the skin injury by occupational health education in glass fiber workers. Methods: We selected 257 on-the-job employees as the research object in a ceramic enterprise in Nanjing from June 2018 to August 2019, with the method of cluster random sampling. According to Solomon's design, the intervention group in which we took measures with health education was divided into RG(1) (O(1)XO(2)) and RG(3) (XO(5)) group, and the control group where we didn't take any intervention was divided into RG(2) (O(3)-O(4)) and RG(4) (-O(6)) group. The intervention effect of health education on the occupational protection of glass fiber workers was evaluated by the results of questionnaire. Results: After training, the average score of occupational health knowledge in the intervention group was 27.34 points higher than that before training, the intervention index was 1.42, 23.62-27.73 points higher than the control glass fiber workers and 33.62-35.52 points higher than the control glass non-glass fiber workers; Compared with the control group, the positive attitude rate of fiber glass workers in the intervention group increased by 13.28%, 13.51%, 11.68% and 11.48%, and the intervention indexes were 1.18, 1.17, 1.14 and 1.15, which was corresponding to using protective cream, wearing gloves, wearing working clothes, washing hands and bathing after work, respectively; Compared with the control group, the implementation rate of occupational protection measures which were represented by wearing gloves、washing hands and bathing for glass fiber workers in the intervention group increased by 29.25% and 7.27% respectively, and the intervention indexes were 1.43 and 1.08 respectively; The skin injury rate of fiberglass workers in the intervention group was reduced by 11.43% comparing to the control group, the intervention index was 1.67. Conclusion: According to the occupational health education of fiberglass workers, it improves the mastery of occupational health knowledge, positive atti-tude rate and the implementation rate of occupational protection measures, meanwhile, it reduces the skin injury rate of the intervention objects to a certain extent.

Novel SLC26A6 gene polymorphism rs184187143 is associated with diabetic ketoacidosis of gestational diabetes

OBJECTIVE

Diabetic ketoacidosis is one of the most serious acute complications of the gestational diabetes and is marked by the triad of the uncontrolled hyperglycemia, acidosis, and ketosis. Diabetic ketoacidosis can be a life-threatening emergency for mother and fetus, whose genetic factors resulting in diabetic ketoacidosis remain unclear. This study aimed to explore the correlation between SLC26A6 gene polymorphism rs184187143 and the risk of diabetic ketoacidosis of gestational diabetic mellitus (GDM).

PATIENTS AND METHODS

A total of 98 patients with GDM and 98 patients with diabetic ketoacidosis of GDM were enrolled. The direct sequencing of the products by Polymerase Chain Reactions of the extracted genomic DNA from the involved patients was performed to analyze the SLC26A6 gene polymorphism rs184187143, and the further genotype frequencies were compared to the statistical analysis of the clinical and biochemical data.

RESULTS

A significantly increased prevalence of the G allele (p = 0.032, OR = 2.326, 95% CI = 1.539-3.516), C/G genotype (p = 0.021, OR = 3.582, 95% CI = 1.216-10.558), and a previously uncharacterized rs184187143, was discovered in the diabetic ketoacidosis of the GDM group. The genotype of SLC26A6 rs184187143 was shown to be markedly associated with increased prevalence of the diabetic ketoacidosis of GDM.

CONCLUSIONS

Our study firstly established that the G allele and C/G genotype of rs184187143 single nucleotide polymorphism (SNP) in SLC26A6 gene was closely linked with the increased risk for the development of the diabetic ketoacidosis of GDM.

An improved DNA marker technique for genetic characterization using RAMP-PCR with high-GC primers

Random amplified polymorphic DNA (RAPD) is a widely used molecular marker technique. As traditional RAPD has poor reproducibility and productivity, we previously developed an improved RAPD method (termed RAMP-PCR), which increased the reproducibility, number of bands, and efficiency of studies on polymorphism. To further develop the efficiency of this method, we used high-GC content primers for improved RAMP-PCR with DNA samples from Lonicera japonica. Comparison of amplification profiles obtained by standard RAPD primers with those obtained by regular PCR and RAMP-PCR, and high-GC primers with regular PCR and RAMP-PCR showed that the average number of bands and polymorphisms per primer gradually and significantly increased (from 6.4 to 15.0 and from 4.6 to 10.2, respectively). Cluster dendrograms showed similar results, indicating that this new method is consistent and reproducible. A total of 22 samples from different species, including plants, animals, and humans, were used for RAMP-PCR with high-GC primers. Multiple bands were successfully amplified from all samples, demonstrating that this method is a reliable technique with consistent results and may be of general interest in studies on different genera and species. We developed highly effective DNA markers, which can provide a more effective and potentially valuable approach than traditional RAPD for the genetic identification of various organisms, particularly of medicinal plants.

Development and significance of SCAR marker QG12-5 for Canarium album (Lour.) Raeusch by molecular cloning from improved RAPD amplification

Sequence-characterized amplified region (SCAR) is a valuable molecular marker for the genetic identification of any species. This marker is mainly derived from molecular cloning of random amplified polymorphic DNA (RAPD). We have previously reported the use of an improved RAPD technique for the genetic characterization of different samples of Canarium album (Lour.) Raeusch (C. album). In this study, DNA fragments were amplified using improved RAPD amplified from different samples of C. album. The amplified DNA fragment was excised, purified from an agarose gel and cloned into a pGM-T vector; subsequently, a positive clone, called QG12-5 was identified by PCR amplification and enzymatic digestion and sequenced by Sanger di-deoxy sequencing method. This clone was revealed consisting of 510 nucleotides of C. album. The SCAR marker QG12-5 was developed using specifically designed PCR primers and optimized PCR conditions. This SCAR marker expressed seven continuous "TATG" [(TATG)n] tandem repeats, which was found to characterize C. album. Subsequently, this novel SCAR marker was deposited in GenBank with accession No. KT359568. Therefore, we successfully developed a C. album-specific SCAR marker for the identification and authentication of different C. album species in this study.

Development of two novel specific SCAR markers by cloning improved RAPD fragments from the medicinal mushroom Ganoderma lucidium (Leysser: Fr) Karst

Development of sequence-characterized amplified region (SCAR) markers from random-amplified polymorphic DNA (RAPD) fragments is a valuable molecular approach for the genetic identification of different species. By using SCAR markers, molecular analysis is reduced to a simple polymerase chain reaction (PCR) analysis using primers designed from the amplicon sequence of RAPD. In this study, the DNA fragments from an improved RAPD amplification of Ganoderma species were cloned into a pGM-T vector; positive clones were identified by PCR amplification and enzymatic digestion, and finally, DNA fragments were sequenced using the Sanger sequencing method for developing the SCAR markers. Two SCAR markers, named LZ4-1 with 534 nucleotides, and LZ5-2 with 337 nucleotides were identified, which are specific to Ganoderma lucidium (Leysser: Fr) Karst species. BLAST of these two nucleotide sequences in the GenBank database showed no identity to other species. We deposited these sequences into the GenBank database (LZ4-1 accession No. KM391933, LZ5-2 accession No. KM391934). PCR assays confirmed them as novel molecular markers for G. lucidium (Leysser: Fr) Karst, which might be used for genetic authentication of adulterant samples. Thus, our study developed two specific SCAR markers for identifying and distinguishing the medicinal mushroom G. lucidium (Leysser: Fr) Karst from other Ganoderma species.

[Retrospective cohort study for the impact on readmission of patients with ischemic stroke after treatment of aspirin plus clopidogrel or aspirin mono-therapy]

OBJECTIVE

To see the influence of different antiplatelet therapies on stroke patients' readmission by performing a deep data-mining into Beijing Healthcare Insuring Database, based on a large sample size.

METHODS

Aretrospective cohort study, was adopted to extract patients primarily diagnosed as ischemic stroke from healthcare database. The first hospital records were considered as the patient's baseline in this study, who were divided into MAPT (aspirin) and DAPT (aspirin and clopidogrel) according to the patient's baseline medications. A follow-up was conducted to see whether the patients would have rehospitalization record because of major result events after medication. The major result events, included: (1) recurrence of ischemic stroke; (2) hemorrhagic transformation of ischemic stroke; (3) myocardial infarction; (4) the digestive hemorrhage. The Kaplan-Meier figure was used to compare the survival situations between these two groups, the log-rank test was used to test the difference of the survival curve, and 1:1 propensity score matching was calculated from the patients' baseline data. Cox proportional hazards model was used to calculate the hazard ratio (HR).

RESULTS

A total of 27 695 patients From January 2010 to September 2013 were included, 4 047 with DAPT, and 23 648 with MAPT. Because the baseline characteristics of the patients was disequilibrium, so we used 1:1 propensity score matching, after which, the number of the two groups was 4 046 each. Adjusted for the general demographic characteristics such as age, sex, nationality, complication and drug combination, no statistical significance was observed between the survival curves of the two groups (P=0.06). HR value of major result events between the groups was 0.91 (0.82-1.01, P=0.07), which was not statistically significant. The covariate gender HR=1.36 (1.20-1.55, P<0.05), accompanied by diabetes HR= 1.36 (1.20-1.54, P<0.05), dyslipidemia HR=1.13 (1.00-1.27, P=1.13), heart disease HR=1.39 (1.22-1.58, P<0.05) was statistically significant. Drug combination with other antiplatelet agents HR=1.05 (0.95-1.17, P>1.05) did not increase the risk of readmission.

CONCLUSION

There was no difference in prevention of readmission between patients with DAPT and MAPT. Patients with complications should actively treat the complications at the same time as they prevent recurrence after first attack.

Development of novel SCAR markers for genetic characterization of Lonicera japonica from high GC-RAMP-PCR and DNA cloning

Sequence-characterized amplified region (SCAR) markers were further developed from high-GC primer RAMP-PCR-amplified fragments from Lonicera japonica DNA by molecular cloning. The four DNA fragments from three high-GC primers (FY-27, FY-28, and FY-29) were successfully cloned into a pGM-T vector. The positive clones were sequenced; their names, sizes, and GenBank numbers were JYHGC1-1, 345 bp, KJ620024; YJHGC2-1, 388 bp, KJ620025; JYHGC7-2, 1036 bp, KJ620026; and JYHGC6-2, 715 bp, KJ620027, respectively. Four novel SCAR markers were developed by designing specific primers, optimizing conditions, and PCR validation. The developed SCAR markers were used for the genetic authentication of L. japonica from its substitutes. This technique provides another means of developing DNA markers for the characterization and authentication of various organisms including medicinal plants and their substitutes.

Isolation and analysis of cell-free fetal DNA from maternal peripheral blood in Chinese women

Non-invasive prenatal diagnosis is used to detect the genetic material of the fetus by isolating the cell-free fetal DNA (cffDNA) from maternal peripheral blood. In order to establish an isolation method for cffDNA from maternal peripheral blood in Chinese women, the cffDNA was acquired with a two-step centrifugation using a QlAamp DNA Blood mini kit. The SRY gene of plasma DNA was amplified by polymerase chain reaction (PCR). Real-time quantitative PCR was used to measure the concentration of cffDNA in maternal peripheral blood in different pregnant women. The results of the SRY gene amplification of plasma DNA from pregnant women was the same as that of the amniocyte DNA. The average concentration of cffDNA in maternal peripheral blood of pregnant women in different gestational stages was 0.98 ng/mL (0.26-1.49 ng/mL), 1.43 ng/mL (0.46- 2.34 ng/mL), and 1.95 ng/mL (0.65-6.81 ng/mL) from early, middle, and late gestational stages, respectively. The mean of cffDNA from total DNA in plasma in different stages of gestation was 22.28% (9.86-27.81%). The lowest concentration of DNA amplified by nested-PCR in our research was 10-4-10-3 ng/μL. The isolation method for cffDNA from maternal peripheral blood was successfully established and further research into its applications will be conducted.

Identification of the origin of marker chromosomes by two-color fluorescence in situ hybridization and polymerase chain reaction in azoospermic patients

Y chromosomal microdeletions at the azoospermia factor locus and chromosome abnormalities have been implicated as the major causes of idiopathic male infertility. A marker chromosome is a structurally abnormal chromosome in which no part can be identified by cytogenetics. In this study, to identify the origin of the marker chromosomes and to perform a genetic diagnosis of patients with azoospermia, two-color fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR) techniques were carried out. The marker chromosomes for the two patients with azoospermia originated in the Y chromosome; it was ascertained that the karyotype of both patients was 46,X, ish del(Y)(q11)(DYZ3+, DXZ1-). The combination of two-color FISH and PCR techniques is an important method for the identification of the origin of marker chromosomes. Thus, genetic counseling and a clear genetic diagnosis of patients with azoospermia before intracytoplasmic sperm injection or other clinical managements are important.

Genome-wide mapping of Myc binding and gene regulation in serum-stimulated fibroblasts

The transition from quiescence to proliferation is a key regulatory step that can be induced by serum stimulation in cultured fibroblasts. The transcription factor Myc is directly induced by serum mitogens and drives a secondary gene expression program that remains largely unknown. Using mRNA profiling, we identify close to 300 Myc-dependent serum response (MDSR) genes, which are induced by serum in a Myc-dependent manner in mouse fibroblasts. Mapping of genomic Myc-binding sites by ChIP-seq technology revealed that most MDSR genes were directly targeted by Myc, but represented a minor fraction (5.5%) of all Myc-bound promoters (which were 22.4% of all promoters). Other target loci were either induced by serum in a Myc-independent manner, were not significantly regulated or were negatively regulated. MDSR gene products were involved in a variety of processes, including nucleotide biosynthesis, ribosome biogenesis, DNA replication and RNA control. Of the 29 MDSR genes targeted by RNA interference, three showed a requirement for cell-cycle entry upon serum stimulation and 11 for long-term proliferation and/or survival. Hence, proper coordination of key regulatory and biosynthetic pathways following mitogenic stimulation relies upon the concerted regulation of multiple Myc-dependent genes.

Anomalous line shape of the cross section for e{+}e{-}--> hadrons in the center-of-mass energy region between 3.650 and 3.872 GeV

We observe an obvious anomalous line shape of the e;{+}e;{-}--> hadrons total cross sections in the energy region between 3.700 and 3.872 GeV. It is inconsistent with the explanation for only one simple psi(3770) resonance with a statistical significance of 7sigma. The anomalous line shape may be explained by two possible enhancements of the inclusive hadron production near the center-of-mass energies of 3.764 and 3.779 GeV, indicating that either there is likely a new structure in addition to the psi(3770) resonance around 3.773 GeV, or there are some physics effects reflecting the DD[over ] production dynamics.

Search for the invisible decay of J/psi in psi(2S) --> pi(+)pi(-) J/psi

Using psi(2S) --> pi(+)pi(-) J/psi events in a sample of 14.0 x 10(6) psi(2S) decays collected with the BES-II detector, a search for the decay of the J/psi to invisible final states is performed. No signal is found, and an upper limit at the 90% confidence level is determined to be 1.2 x 10(-2) for the ratio B(J/psi --> invisible)/B(J/psi-->mu(+)mu(-)). This is the first search for J/psi decays to invisible final states.

Observation of Y(2175) in J/psi --> etaphif0 (980)

The decays of J/psi --> etaphif(0)(980)[eta --> gammagamma, phi --> K(+) K(-), f(0)(980) --> pi(+)pi(-)] are analyzed using a sample of 5.8 x 10(7) J/psi events collected with the BESII detector at the Beijing Electron-Positron Collider. A structure at around 2.18 GeV/c(2) with about 5 sigma significance is observed in the phif(0)(980) invariant mass spectrum. A fit with a Breit-Wigner function gives the peak mass and width of m = 2.186+/-0.010(stat)+/-0.006(syst) GeV/c(2) and Gamma = 0.065+/-0.023(stat)+/-0.017(syst) GeV/c(2), respectively, which are consistent with those of Y(2175), observed by the BABAR Collaboration in the initial-state radiation process e(+)e(-) --> gamma(ISR) phif(0)(980). The production branching ratio is determined to be Br(J/psi --> etaY(2175))Br(Y(2175)- -> phif(0)(980))Br(f(0)(980) --> pi(+)pi(-)) = [3.23+/-0.75(stat)+/-0.73(syst)] x 10(-4), assuming that the Y(2175) is a 1(--) state.

Measurement of psi2S radiative decays

Using 14 x 10(6) psi(2S) events accumulated at the BESII detector, we report first measurements of branching fractions or upper limits for psi(2S) decays into gammapp, gamma2(pi+pi-), gammaKS0K+pi-+c.c., gammaK+K-pi+pi-, gammaK*0K-pi++c.c., gammaK*0K*0, gammapi+pi-pp, gamma2(K+K-), gamma3(pi+pi-), and gamma2(pi+pi-)K+K- with the invariant mass of hadrons below 2.9 GeV/c2. We also report branching fractions of psi(2S) decays into 2(pi+pi-)pi0, omegapi+pi-, omegaf2(1270), b1+/-pi-/+, and pi02(pi+pi-)K+K-.

Measurements of the continuum R(uds) and R values in e(+)e(-) annihilation in the energy region between 3.650 and 3.872 GeV

We report measurements of the continuum R(uds) near the center-of-mass energy of 3.70 GeV, the R[uds(c)+psi(3770)](s) and the R(had)(s) values in e(+)e(-) annihilation at 68 energy points in the energy region between 3.650 and 3.872 GeV with the BES-II detector at the BEPC Collider. We obtain the R(uds) for the continuum light hadron (containing u, d, and s quarks) production near the DD threshold to be R(uds)=2.141+/-0.025+/-0.085.

Search for invisible decays of eta and eta' in J/psi --> phi eta and phi eta'

Using a data sample of 58 x 10(6) J/psi decays collected with the Beijing Spectrometer II detector at the Beijing Electron Positron Collider, searches for invisible decays of eta and eta' in J/psi to phi eta and phi eta' are performed. The phi signals, which are reconstructed in K+K- final states, are used to tag the eta and eta' decays. No signals are found for the invisible decays of either eta or eta', and upper limits at the 90% confidence level are determined to be 1.65 x 10(-3) for the ratio B(eta-->invisible)/B(eta --> gamma gamma) and 6.69 x 10(-2) for B(eta' --> invisible)/B(eta' --> gammagamma). These are the first searches for eta and eta' decays into invisible final states.

Observation of a broad 1-- resonant structure around 1.5 GeV/c2 in the K+K- mass spectrum in J/psi-->K+K-pi0

A broad peak is observed at low K+K- invariant mass in J/psi-->K+K-pi(0) decays found in a sample of 5.8x10(7) J/psi events collected with the BESII detector. The statistical significance of the broad resonance is much larger than 5sigma. A partial wave analysis shows that the J;{PC} of this structure is 1--. Its pole position is determined to be [1576(-55)(+49)(stat)-91+98(syst)] MeV/c(2)-i/2[818(-23)(+22)(stat)-133+64(syst)] MeV/c(2). These parameters are not compatible with any known meson resonances.

Measurements of the branching fractions for psi(3770)-->D(0)D[over ](0), D+D-, DD[over ], and the resonance parameters of psi(3770) and psi(2S)

We measure the branching fractions for psi(3770)-->D(0)D[over ](0), D+D-, DD[over ], and non-DD[over ] to be (46.7+/-4.7+/-2.3)%, (36.9+/-3.7+/-2.8)%, (83.6+/-7.3+/-4.2)%, and (16.4+/-7.3+/-4.2)%, respectively. The resonance parameters of psi(3770) and psi(2S) are measured to be M_(psi(3770))=3772.2+/-0.7+/-0.3 MeV, Gamma_(psi(3770))(tot)=26.9+/-2.4+/-0.3 MeV, and Gamma_(psi(3770))(ee)=251+/-26+/-11 eV; M_(psi(2S))=3685.5+/-0.0+/-0.3 MeV, Gamma_(psi(2S))(tot)=331+/-58+/-2 keV, and Gamma_(psi(2S))(ee)=2.330+/-0.036+/-0.110 keV. We also measure the light hadron R value to be R(uds)=2.262+/-0.054+/-0.109 in the energy region from 3.660 to 3.872 GeV.

Observation of two new N* peaks in J/psi-->ppi-n and ppi+n decays

The decay J/psi-->NNpi provides an effective isospin 1/2 filter for the piN system due to isospin conservation. Using 58x10(6) J/psi decays collected with the Beijing Electromagnetic Spectrometer at the Beijing Electron Positron Collider, more than 100 thousand J/psi-->ppi-n+c.c. events are obtained. Besides the two well-known N* peaks at around 1500 MeV/c2 and 1670 MeV/c2, there are two new, clear N* peaks in the ppi invariant mass spectrum around 1360 MeV/c2 and 2030 MeV/c2 with statistical significance of 11sigma and 13sigma, respectively. We identify these as the first direct observation of the N*(1440) peak and a long-sought missing N* peak above 2 GeV/c2 in the piN invariant mass spectrum.

Observation of a near-threshold enhancement in the omega(phi) mass spectrum from the doubly OZI-suppressed decay J/psi-->gamma(omega)phi

An enhancement near threshold is observed in the omega(phi) invariant mass spectrum from the doubly Okubo-Zweig-Iizuka-suppressed decays of J/psi-->gamma(omega)phi, based on a sample of 5.8 x 10(7) J/psi events collected with the BESII detector. A partial wave analysis shows that this enhancement favors JP=0+, and its mass and width are M=1812(+19)(-26)(stat)+/-18(syst) MeV/c2 and Gamma=105+/-20(stat)+/-28(syst) MeV/c2. The product branching fraction is determined to be B(J/psi-->gammaX)B(X-->omega(phi))=[2.61+/-0.27(stat)+/-0.65(syst)]x10(-4).

Observation of a resonance in Chi(1835) in J/psi --> gammapi+ pi- eta-

The decay channel J/psi --> gamma(pi)(+)pi(-)eta is analyzed using a sample of 5.8 x 10(7) J/psi events collected with the BESII detector. A resonance, the Chi(1835), is observed in the pi(+)pi(-)eta invariant-mass spectrum with a statistical significance of 7.7 sigma. A fit with a Breit-Wigner function yields a mass M = 1833.7 +/- 6.1(stat) +/- 2.7(syst) MeV/c(2), a width Tau = 67.7 +/- 20.3(stat) +/- 7.7(syst) MeV/c(2), and a product branching fraction B(J/psi --> gammaChi) . B(Chi --> pi(+)pi(-)eta) = [2.2 +/- 0.4(stat) +/- 0.4(syst)] x 10(-4). The mass and width of the Chi(1835) are not compatible with any known meson resonance. Its properties are consistent with expectations for the state that produces the strong pp mass threshold enhancement observed in the J/psi --> gammapp process at BESII.

The transcriptional landscape of the mammalian genome

This study describes comprehensive polling of transcription start and termination sites and analysis of previously unidentified full-length complementary DNAs derived from the mouse genome. We identify the 5' and 3' boundaries of 181,047 transcripts with extensive variation in transcripts arising from alternative promoter usage, splicing, and polyadenylation. There are 16,247 new mouse protein-coding transcripts, including 5154 encoding previously unidentified proteins. Genomic mapping of the transcriptome reveals transcriptional forests, with overlapping transcription on both strands, separated by deserts in which few transcripts are observed. The data provide a comprehensive platform for the comparative analysis of mammalian transcriptional regulation in differentiation and development.

Observation of a threshold enhancement in the plambda invariant-mass spectrum

An enhancement near the m(p)+M(Lambda) mass threshold is observed in the combined pLambda and pLambda invariant-mass spectrum from J/psi-->pK(-)Lambda;+c.c. decays. It can be fit with an S-wave Breit-Wigner resonance with a mass m=2075+/-12(stat)+/-5(syst) MeV and a width of Gamma=90+/-35(stat)+/-9(syst) MeV; it can also be fit with a P-wave Breit-Wigner resonance. Evidence for a similar enhancement is also observed in psi(')-->pK(-)Lambda;+c.c. decays. The analysis is based on samples of 5.8x10(7)J/psi and 1.4x10(7)psi(') decays accumulated in the BES II detector at the Beijing Electron-Positron Collider.

Observation of the decay psi(2S)-->K0SK0L

The decay psi(2S)-->K(0)(S)K(0)(L) is observed using psi(2S) data collected with the Beijing Spectrometer at the Beijing Electron-Positron Collider; the branching fraction is determined to be B(psi(2S)-->K(0)(S)K(0)(L))=(5.24+/-0.47+/-0.48)x10(-5). Compared with J/psi-->K(0)(S)K(0)(L), the psi(2S) branching fraction is enhanced relative to the prediction of the perturbative QCD "12%" rule. The result, together with the branching fractions of psi(2S) decays to other pseudoscalar meson pairs (pi(+)pi(-) and K+K-), is used to investigate the relative phase between the three-gluon and the one-photon annihilation amplitudes of psi(2S) decays.

Observation of a near-threshold enhancement in the pp mass spectrum from radiative J/psi-->gammapp decays

We observe a narrow enhancement near 2m(p) in the invariant mass spectrum of pp pairs from radiative J/psi-->gammapp decays. No similar structure is seen in J/psi-->pi(0)pp decays. The results are based on an analysis of a 58 x 10(6) event sample of J/psi decays accumulated with the BESII detector at the Beijing electron-positron collider. The enhancement can be fit with either an S- or P-wave Breit-Wigner resonance function. In the case of the S-wave fit, the peak mass is below 2m(p) at M=1859(+3)(-10) (stat)+5-25(syst) MeV/c(2) and the total width is Gamma<30 MeV/c(2) at the 90% confidence level. These mass and width values are not consistent with the properties of any known particle.

Measurements of the cross section for e(+)e(-) --> hadrons at center-of-mass energies from 2 to 5 GeV

We report values of R = sigma(e(+)e(-)-->hadrons)/sigma(e(+)e(-)-->mu(+)mu(-)) for 85 center-of-mass energies between 2 and 5 GeV measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider.

Measurement of the total cross section for hadronic production by e(+)e(-) annihilation at energies between 2.6-5 GeV

Using the upgraded Beijing Spectrometer, we have measured the total cross section for e(+)e(-) annihilation into hadronic final states at center-of-mass energies of 2.6, 3.2, 3.4, 3.55, 4.6, and 5.0 GeV. Values of R, sigma(e(+)e(-)-->hadrons)/sigma(e(+)e(-)-->&mgr;(+)&mgr;(-)), are determined.

RNase E is required for the maturation of ssrA RNA and normal ssrA RNA peptide-tagging activity

During recent studies of ribonucleolytic "degradosome" complexes of Escherichia coli, we found that degradosomes contain certain RNAs as well as RNase E and other protein components. One of these RNAs is ssrA (for small stable RNA) RNA (also known as tm RNA or 10Sa RNA), which functions as both a tRNA and mRNA to tag the C-terminal ends of truncated proteins with a short peptide and target them for degradation. Here, we show that mature 363-nt ssrA RNA is generated by RNase E cleavage at the CCA-3' terminus of a 457-nt ssrA RNA precursor and that interference with this cleavage in vivo leads to accumulation of the precursor and blockage of SsrA-mediated proteolysis. These results demonstrate that RNase E is required to produce mature ssrA RNA and for normal ssrA RNA peptide-tagging activity. Our findings indicate that RNase E, an enzyme already known to have a central role in RNA processing and decay in E. coli, also has the previously unsuspected ability to affect protein degradation through its role in maturation of the 3' end of ssrA RNA.

Corticotropin-releasing factor enhances brain-derived neurotrophic factor gene expression to facilitate memory retention in rats

In the present study, we investigated the effects of corticotropin-releasing factor (CRF) injected into the dentate gyrus (DG) of the hippocampus on brain-derived neurotrophic factor (BDNF) mRNA expression and studied whether N-methyl-D-aspartate (NMDA) receptor mediates the effects of CRF on BDNF mRNA expression in the DG. Since both CRF and BDNF gene expressions are involved in memory processing in rats, we further investigated whether CRF facilitates memory retention through enhanced BDNF mRNA expression in the hippocampus. Effect of direct BDNF injection to the DG on retention performance in rats was also assessed. Results indicated that intra-DG CRF injection produced a dose-dependent (0.1 microg, 1.0 microg and 10 microg) increase in BDNF mRNA level, while intra-DG MK801 injection produced a dose-dependent (0.08 microg, 0.2 microg and 2.0 microg) decrease in BDNF mRNA expression in the DG. MK801, at a dose having no significant effect alone (0.08 microg), significantly antagonized the effect of CRF on BDNF mRNA expression. On the other hand, CRF (1.0 microg) consistently and markedly improved retention performance in rats in an inhibitory avoidance learning task. BDNF antisense oligonucleotide treatment, at a concentration which did not affect retention performance alone (0.5 mM), blocked the memory-enhancing effect of CRF. However, direct and chronic BDNF injection to the DG did not improve memory performance in rats. These results together suggest that at least one of the mechanisms responsible for the memory-facilitating effect of CRF is mediated through enhanced BDNF mRNA expression in the hippocampus. The lack of an effect of intra-DG BDNF injection on memory retention is also discussed.

The proapoptotic function of Drosophila Hid is conserved in mammalian cells

Three genes-reaper, grim, and hid-are crucial to the regulation of programmed cell death in Drosophila melanogaster. Mutations involving all three genes virtually abolish apoptosis during development, and homozygous hid mutants die as embryos with extensive defects in apoptosis. Although Hid is central to apoptosis in Drosophila, it has no mammalian homologue identified to date. We present evidence that expression of Drosophila Hid in mammalian cells induces apoptosis. This activity is subject to regulation by inhibitors of mammalian cell death. We show that the N terminus of Hid, which is a region of homology with Reaper and Grim, is essential for Hid's function in mammalian cells. We demonstrate that Hid is localized to the mitochondria via a hydrophobic region at its C terminus and functionally interacts with BclXL. This study shows that the function of Hid as a death inducer in Drosophila is conserved in mammalian cells and argues for the existence of a mammalian homologue of this critical regulator of apoptosis.

RNA components of Escherichia coli degradosome: evidence for rRNA decay

Recently, we found that a multicomponent ribonucleolytic degradosome complex formed around RNase E, a key mRNA-degrading and 9S RNA-processing enzyme, contains RNA in addition to its protein components. Herein we show that the RNA found in the degradosome consists primarily of rRNA fragments that have a range of distinctive sizes. We further show that rRNA degradation is carried out in the degradosome by RNase E cleavage of A+U-rich single-stranded regions of mature 16S and 23S rRNAs. The 5S rRNA, which is known to be generated by RNase E processing of the 9S precursor, was also identified in the degradosome, but tRNAs, which are not cleaved by RNase E in vitro, were absent. Our results, which provide evidence that decay of mature rRNAs occurs in growing Escherichia coli cells in the RNA degradosome, implicate RNase E in degradosome-mediated decay.

Brain-derived neurotrophic factor antisense oligonucleotide impairs memory retention and inhibits long-term potentiation in rats

We have examined the relationship between brain-derived neurotrophic factor gene expression in the hippocampus and memory retention as well as long-term potentiation of rats. One-way inhibitory avoidance learning was adopted as the behavioural paradigm. Results revealed that brain-derived neurotrophic factor messenger RNA levels in the dentate gyrus of the hippocampus were markedly increased at 1 h, 3 h and 6 h post-training in rats showing good retention performance when compared with the poor retention controls. Direct injection of brain-derived neurotrophic factor antisense oligonucleotide into the dentate gyrus of the hippocampus before memory consolidation takes place markedly impaired retention performance in rats. It also significantly decreased brain-derived neurotrophic factor messenger RNA level in the dentate gyrus. The same antisense treatment also markedly reduced the amplitude and slope of excitatory postsynaptic potential as well as the brain-derived neurotrophic factor messenger RNA level in the dentate gyrus. These results suggest that hippocampal brain-derived neurotrophic factor gene expression plays an important role in the memory consolidation process and in the expression of long-term potentiation in rats. These results provide the first evidence to relate brain-derived neurotrophic factor gene expression and memory function in vertebrates. It further suggests that brain-derived neurotrophic factor gene expression is involved in behavioural plasticity.

The gene encoding UDP-glucose pyrophosphorylase is required for the synthesis of xanthan gum in Xanthomonas campestris

Xanthomonas campestris pv. campestris produces a large quantity of exopolysaccharide, xanthan gum, rendering the colonies mucoid. G76E was a non-mucoid mutant isolated from Xc17 by Tn5 mutagenesis. A 3.0-kb KpnI-EcoRI fragment from the Xc17 chromosome was able to restore mucoid phenotype to G76E. Sequence analysis of the region responsible for the restoration revealed an open reading frame, ORF324, able to encode a polypeptide of 35,232 Da which shows striking similarity to the UDP-glucose pyrophosphorylases from bacteria. The activity of UDP-glucose pyrophosphorylase reduced drastically in G76E was found to be regained in the presence of the cloned 3.0-kb KpnI-EcoRI fragment. In vitro expression of the gene in the S30 transcription/translation system produced a protein of ca. 35 kDa.

Proteins associated with RNase E in a multicomponent ribonucleolytic complex

The Escherichia coli endoribonuclease RNase E is essential for RNA processing and degradation. Earlier work provided evidence that RNase E exists intracellularly as part of a multicomponent complex and that one of the components of this complex is a 3'-to-5' exoribonuclease, polynucleotide phosphorylase (EC 2.7.7.8). To isolate and identify other components of the RNase E complex, FLAG-epitope-tagged RNase E (FLAG-Rne) fusion protein was purified on a monoclonal antibody-conjugated agarose column. The FLAG-Rne fusion protein, eluted by competition with the synthetic FLAG peptide, was found to be associated with other proteins. N-terminal sequencing of these proteins revealed the presence in the RNase E complex not only of polynucleotide phosphorylase but also of DnaK, RNA helicase, and enolase (EC 4.2.1.11). Another protein associated only with epitope-tagged temperature-sensitive (Rne-3071) mutant RNase E but not with the wild-type enzyme is GroEL. The FLAG-Rne complex has RNase E activity in vivo and in vitro. The relative amount of proteins associated with wild-type and Rne-3071 expressed at an elevated temperature differed.

Characterization of yeast translation initiation factor 1A and cloning of its essential gene

Translation initiation factor eIF1A is required in vitro for maximal rates of protein synthesis in mammalian systems. It functions primarily by dissociating ribosomes and stabilizing 40 S preinitiation complexes. To better elucidate its precise role in promoting the translation initiation process, the yeast form of eIF1A has been identified in Saccharomyces cerevisiae and purified to homogeneity on the basis of its cross-reaction with antibodies prepared against mammalian eIF1A. The apparent mass of yeast eIF1A (22 kDa) resembles that of the mammalian homolog (20 kDa), and the yeast factor is active in stimulating methionyl-puromycin synthesis in an assay composed of mammalian components. The gene encoding yeast eIF1A, named TIF11, was cloned and shown to be single copy. TIF11 encodes a protein comprising 153 amino acids (17.4 kDa); the deduced amino acid sequence exhibits 65% identity with the sequence of human eIF1A. Both human and yeast eIF1A contain clusters of positive residues at the N terminus and negative residues at the C terminus. Deletion/disruption of TIF11 demonstrates that eIF1A is essential for cell growth. Expression of human eIF1A cDNA rescues the growth defect of TIF11-disrupted cells, indicating that the structure/function of yeast and mammalian eIF1A is highly conserved.

Protein synthesis initiation factor eIF-1A is a moderately abundant RNA-binding protein

Eukaryotic initiation factor (eIF) 1A (formerly called eIF-4C) is a small protein that promotes dissociation of 80 S ribosomes into subunits, stabilizes methionyl-tRNA binding to 40 S ribosomal subunits, and is required for the binding of mRNA to ribosomes. The sequence of eIF-1A derived from its cloned cDNA possesses a high frequency of basic residues and acidic residues at its N and C termini, respectively. Northwestern blotting with a fragment of mRNA indicates that eIF-1A binds RNA. Overexpression of the human eIF-1A cDNA in Escherichia coli and subsequent purification enabled us to prepare large quantities of active factor. The level of eIF-1A in HeLa cells determined by Western immunoblotting is 0.01% of total protein, which corresponds to 0.2 molecules of eIF-1A/ribosome. The moderate abundance means that eIF-1A is equal to or in excess of native 40 S subunits and suggests that the factor may not be limiting for protein synthesis, a conclusion reinforced by the failure of overproduced eIF-1A to stimulate translation rates in transiently transfected COS-1 cells. S1 nuclease protection and primer extension analyses show that eIF-1A mRNA possesses an unusually long 5'-untranslated leader that is very G/C-rich (72%). Unexpectedly, the mRNA is efficiently translated in HeLa cells as judged by polysome profile analyses.

The major protein of messenger ribonucleoprotein particles in somatic cells is a member of the Y-box binding transcription factor family

A cDNA encoding the major core protein, p50, of cytoplasmic messenger ribonucleoprotein particles (mRNPs) of somatic cells was cloned from a rabbit reticulocyte cDNA library. From the derived 324-amino acid sequence, p50 is identified as a member of the Y-box binding transcription factor family. The protein was earlier described as a repressor of globin mRNA translation. These findings suggest that p50 may affect protein biosynthesis at two levels: mRNA transcription in the nucleus and mRNA translation in the cytoplasm. Together with recently published results showing that masked mRNA in germ cells also is associated with proteins of the Y-box binding protein family, the present finding indicates that these proteins are universal core proteins responsible for the formation of cytoplasmic mRNPs in eukaryotes. Highly purified p50 forms large 18 S homomultimeric complexes with a molecular mass of about 800 kilodaltons and melts RNA secondary structure. This suggests that p50 may affect translation by changing the overall structure of the mRNA.

Determination of the amino acid sequence of rabbit, human, and wheat germ protein synthesis factor eIF-4C by cloning and chemical sequencing

The small eukaryotic initiation factor (eIF)-4C is implicated in the initiation pathway, where it enhances ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA(i) to 40 S ribosomal subunits. In order to elucidate the function of eIF-4C, its structure has been further characterized. The amino acid sequence of many peptides from rabbit reticulocyte and wheat germ eIF-4C have been determined chemically. From the chemical sequencing of the rabbit protein, it was noted that at least two different eIF-4C molecules were present which differed by conservative substitutions at three positions (2 aspartic acid for glutamic acid switches and 1 valine for isoleucine switch). By the use of unique sequences with low codon degeneracy, primers were used to obtain a polymerase chain reaction product of appropriate size and sequence. This product was then used to isolate full-length coding sequence cDNA clones for human eIF-4C. A similar strategy was used to design PCR primers and then isolate a wheat cDNA clone which lacked the coding region for the first 23 amino acids, but contained a complete 3'-untranslated region. The protein amino acid sequence of wheat germ eIF-4C is 68% identical with the mammalian protein, and, allowing for the most conservative substitutions, the proteins are 76% similar. Both the mammalian and wheat germ proteins are 143 amino acids in length and have molecular weights of about 16,400. A unique feature of eIF-4C is its apparent "polarity" as 9 of the first 15 amino acids are basic while 13 of the last 20 amino acids are acidic. This dipole nature may enable the protein to interact with both the ribosome (perhaps via the rRNA) and other translation initiation factors.

A liver-specific nuclear factor interacts with the promoter region of the large surface protein gene of human hepatitis B virus

The outer envelope of the 42-nm virion of the human hepatitis B virus (HBV) is composed of the large, the middle, and the major surface proteins. Whereas the middle and the major surface proteins are transcribed from the SPII promoter of the pre-S/S gene, the large surface protein is transcribed from the SPI promoter located upstream of SPII. We have previously shown that transcription of SPI (comprising nucleotides [nt] -380 to +17) occurs preferentially in differentiated hepatoma cell lines (H.K. Chang and L.P. Ting, Virology 170:176-183, 1989). In this report, we further demonstrated that a sequence of 95 base pairs in the upstream region of SPI (nt -95 to +17) was necessary and sufficient for such preferential expression in differentiated hepatoma cells. By analysis of the expression of the chloramphenicol acetyltransferase gene in a series of mutants with deletions at the 5' end of SPI, we identified a positive transcriptional cis-acting element mapping at nt -95 to -72 which appears to play a key role in the regulation of the expression of the large surface protein. This region shared a high degree of sequence homology with regulatory sequences of several liver-specific genes from human, mouse, and rat, with a consensus sequence (G/A)GTTA(A/C)TNNT(C/T)NNC(A/C). We further identified a nuclear factor present in the nuclear extracts of differentiated human hepatoma cell lines which interacted specifically with this element of the SPI promoter. This nuclear factor was similar to the rat liver-specific factor HNF-1, since an oligonucleotide containing the recognition sequence of HNF-1 could efficiently compete for the human factor in a footprinting assay. The sequence at nt -93 to -68 which was bound by this factor in SPI was termed the HNF-1-binding element. Activation of the SPI promoter by human differentiated hepatocyte nuclear factor 1, described in this report, probably explains, first, the formation of the 42-nm virion specifically in liver but not in several other tissues despite the synthesis of the middle and the major surface proteins in those tissues, and second, why only differentiated hepatoma cell lines are able to produce 42-nm-like virion particles on transfection by HBV DNA.

[Level of cyclic AMP-dependent protein kinase isozyme in normal liver and hepatoma tissue and the effect of sodium selenite]

Sodium selenite in normal saline was administered intraperitoneally (1 mg/kg) into mice bearing ascitic hepatocarcinoma for 4 days. The cyclic AMP-dependent protein kinase isozymes (type I and type II) in normal liver and hepatocarcinoma cells were separated and assayed. The results show that the level of type I/II is markedly higher in hepatocarcinoma than in the normal liver cells. Sodium selenite is able to reduce it towards the normal level. Further analysis shows that the chief function of sodium selenite is to reduce the raised level of type I/II in hepatocarcinoma cells which, in fact, is due to the increase of total amount of type I cyclic AMP-dependent protein kinase. This paper presents the speculation that one of the mechanisms of the inhibitory effect of sodium selenite on carcinogenesis may be due to the selective action of this compound on the cyclic AMP-dependent protein kinase isozymes in tumor cells, thus inhibiting cancer cell division and facilitating differentiation and reversion.

In vivo and in vitro release of macromolecules from polymeric drug delivery systems

In vivo release rates of a macromolecule from an ethylene-vinyl acetate copolymer have been shown to be indistinguishable from those of identical implants tested in vitro. The studies were conducted for approximately 2 months, and two different techniques were used to assess release rates. One of these techniques, using [3H]inulin as a marker, may be particularly useful in future studies assessing in vivo release rates from drug delivery systems. The appearance of [3H]inulin in the urine of rats bearing implants allowed continuous monitoring of release. A histological evaluation of tissue sections surrounding polymer implanted for 7 months showed no inflammatory cell reaction.