[A multicenter, retrospective study of pathogenic bacteria distribution and drug resistance in febrile neutropenic patients with hematological diseases in Shanghai]

目的

了解上海地区中性粒细胞缺乏（粒缺）伴发热血液病患者致病细菌的分布及耐药情况。

方法

回顾性分析2012年1月至2014年12月上海市12家医院血液科粒缺伴发热住院患者的临床分离菌株，用纸片扩散法进行药敏试验，WHONET 5.6软件分析病原菌分布及药敏数据。

结果

从上海地区粒缺伴发热患者中共分离出1 260株细菌，其中革兰阳性菌420株（33.3%），革兰阴性菌840株（66.7%）。排在前七位的分别是肺炎克雷伯菌158株（12.5%）、嗜麦芽窄食单胞菌120株（9.5%）、大肠埃希菌115株（9.1%）、铜绿假单胞菌109株（8.7%）、鲍曼不动杆菌83株（6.6%）、金黄色葡萄球菌70株（5.6%）和屎肠球菌63株（5.0%）。呼吸道分泌物标本中，非发酵菌占56.2%（350/623）。其中嗜麦芽窄食单胞菌占15.3%（95/623）。血液标本中，肠杆菌科细菌占42.3%（104/246），凝固酶阴性葡萄球菌占34.6%（85/246）。脓液标本中肠杆菌科细菌占39.4%（76/193），肠球菌属细菌占28.5%（55/193）。耐甲氧西林金黄色葡萄球菌葡萄球菌（MRSA）和耐甲氧西林凝固酶阴性葡萄球菌（MRCNS）的检出率分别为54.3%和82.5%，未发现耐利奈唑胺、万古霉素、替考拉宁葡萄球菌属菌株，耐万古霉素屎肠球菌的检出率为8.9%，肠球菌属未检出耐利奈唑胺的菌株。肠杆菌科细菌对碳青霉烯类药物高度敏感。铜绿假单胞菌对亚胺培南和美罗培南的耐药率已分别达34.1%和15.8%。嗜麦芽窄食单胞菌对米诺环素、左氧氟沙星、复方磺胺甲恶唑等药物敏感。鲍曼不动杆菌仅对头孢哌酮/舒巴坦的耐药率低于10.0%。肺炎克雷伯菌、嗜麦芽窄食单胞菌、铜绿假单胞菌、鲍曼不动杆菌等革兰阴性菌对大多常用抗菌药物的耐药率低于CHINET监测的数据。

结论

粒缺伴感染患者常见感染部位致病菌株分布有其特点，细菌耐药率整体低于CHINET全国医院大样本监测。

Study of the D^{0}→K^{-}μ^{+}ν_{μ} Dynamics and Test of Lepton Flavor Universality with D^{0}→K^{-}ℓ^{+}ν_{ℓ} Decays

Using e^{+}e^{-} annihilation data of 2.93  fb^{-1} collected at center-of-mass energy sqrt[s]=3.773  GeV with the BESIII detector, we measure the absolute branching fraction of D^{0}→K^{-}μ^{+}ν_{μ} with significantly improved precision: B_{D^{0}→K^{-}μ^{+}ν_{μ}}=(3.413±0.019_{stat}±0.035_{syst})%. Combining with our previous measurement of B_{D^{0}→K^{-}e^{+}ν_{e}}, the ratio of the two branching fractions is determined to be B_{D^{0}→K^{-}μ^{+}ν_{μ}}/B_{D^{0}→K^{-}e^{+}ν_{e}}=0.974±0.007_{stat}±0.012_{syst}, which agrees with the theoretical expectation of lepton flavor universality within the uncertainty. A study of the ratio of the two branching fractions in different four-momentum transfer regions is also performed, and no evidence for lepton flavor universality violation is found with current statistics. Taking inputs from global fit in the standard model and lattice quantum chromodynamics separately, we determine f_{+}^{K}(0)=0.7327±0.0039_{stat}±0.0030_{syst} and |V_{cs}|=0.955±0.005_{stat}±0.004_{syst}±0.024_{LQCD}.

Measurement of the Absolute Branching Fraction of the Inclusive Semileptonic Λ_{c}^{+} Decay

Using a data sample of e^{+}e^{-} collisions corresponding to an integrated luminosity of 567  pb^{-1} collected at a center-of-mass energy of sqrt[s]=4.6  GeV with the BESIII detector, we measure the absolute branching fraction of the inclusive semileptonic Λ_{c}^{+} decay with a double-tag method. We obtain B(Λ_{c}^{+}→Xe^{+}ν_{e})=(3.95±0.34±0.09)%, where the first uncertainty is statistical and the second systematic. Using the known Λ_{c}^{+} lifetime and the charge-averaged semileptonic decay width of nonstrange charmed mesons (D^{0} and D^{+}), we obtain the ratio of the inclusive semileptonic decay widths Γ(Λ_{c}^{+}→Xe^{+}ν_{e})/Γ[over ¯](D→Xe^{+}ν_{e})=1.26±0.12.

Measurement of the Branching Fraction For the Semileptonic Decay D^{0(+)}→π^{-(0)}μ^{+}ν_{μ} and Test of Lepton Flavor Universality

Using a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} taken at a center-of-mass energy of 3.773 GeV with the BESIII detector operated at the BEPCII collider, we perform an analysis of the semileptonic decays D^{0(+)}→π^{-(0)}μ^{+}ν_{μ}. The branching fractions of D^{0}→π^{-}μ^{+}ν_{μ} and D^{+}→π^{0}μ^{+}ν_{μ} are measured to be (0.272±0.008_{stat}±0.006_{syst})% and (0.350±0.011_{stat}±0.010_{syst})%, respectively, where the former is of much improved precision compared to previous results and the latter is determined for the first time. Using these results along with previous BESIII measurements of D^{0(+)}→π^{-(0)}e^{+}ν_{e}, we calculate the branching fraction ratios to be R^{0}≡B_{D^{0}→π^{-}μ^{+}ν_{μ}}/B_{D^{0}→π^{-}e^{+}ν_{e}}=0.922±0.030_{stat}±0.022_{syst} and R^{+}≡B_{D^{+}→π^{0}μ^{+}ν_{μ}}/B_{D^{+}→π^{0}e^{+}ν_{e}}=0.964±0.037_{stat}±0.026_{syst}, which are compatible with the theoretical expectation of lepton flavor universality within 1.7σ and 0.5σ, respectively. We also examine the branching fraction ratios in different four-momentum transfer square regions, and find no significant deviations from the standard model predictions.

Observation of the Semileptonic Decay D^{0}→a_{0}(980)^{-}e^{+}ν_{e} and Evidence for D^{+}→a_{0}(980)^{0}e^{+}ν_{e}

Using an e^{+}e^{-} collision data sample of 2.93  fb^{-1} collected at a center-of-mass energy of 3.773 GeV by the BESIII detector at BEPCII, we report the observation of D^{0}→a_{0}(980)^{-}e^{+}ν_{e} and evidence for D^{+}→a_{0}(980)^{0}e^{+}ν_{e} with significances of 6.4σ and 2.9σ, respectively. The absolute branching fractions are determined to be B(D^{0}→a_{0}(980)^{-}e^{+}ν_{e})×B(a_{0}(980)^{-}→ηπ^{-})=[1.33_{-0.29}^{+0.33}(stat)±0.09(syst)]×10^{-4} and B(D^{+}→a_{0}(980)^{0}e^{+}ν_{e})×B(a_{0}(980)^{0}→ηπ^{0})=[1.66_{-0.66}^{+0.81}(stat)±0.11(syst)]×10^{-4}. This is the first time the a_{0}(980) meson has been measured in a D^{0} semileptonic decay, which would open one more interesting page in the investigation of the nature of the puzzling a_{0}(980) states.

Measurement of the Absolute Branching Fraction of the Inclusive Decay Λ_{c}^{+}→Λ+X

Based on an e^{+}e^{-} collision data sample corresponding to an integrated luminosity of 567  pb^{-1} taken at the center-of-mass energy of sqrt[s]=4.6  GeV with the BESIII detector, we measure the absolute branching fraction of the inclusive decay Λ_{c}^{+}→Λ+X to be B(Λ_{c}^{+}→Λ+X)=(38.2_{-2.2}^{+2.8}±0.9)% using the double-tag method, where X refers to any possible final state particles. In addition, we search for direct CP violation in the charge asymmetry of this inclusive decay for the first time, and obtain A_{CP}≡[B(Λ_{c}^{+}→Λ+X)-B(Λ[over ¯]_{c}^{-}→Λ[over ¯]+X)]/[B(Λ_{c}^{+}→Λ+X)+B(Λ[over ¯]_{c}^{-}→Λ[over ¯]+X)]=(2.1_{-6.6}^{+7.0}±1.6)%, a statistically limited result with no evidence of CP violation.

Observation of a_{0}^{0}(980)-f_{0}(980) Mixing

We report the first observation of a_{0}^{0}(980)-f_{0}(980) mixing in the decays of J/ψ→ϕf_{0}(980)→ϕa_{0}^{0}(980)→ϕηπ^{0} and χ_{c1}→a_{0}^{0}(980)π^{0}→f_{0}(980)π^{0}→π^{+}π^{-}π^{0}, using data samples of 1.31×10^{9}  J/ψ events and 4.48×10^{8}  ψ(3686) events accumulated with the BESIII detector. The signals of f_{0}(980)→a_{0}^{0}(980) and a_{0}^{0}(980)→f_{0}(980) mixing are observed at levels of statistical significance of 7.4σ and 5.5σ, respectively. The corresponding branching fractions and mixing intensities are measured and the constraint regions on the coupling constants, g_{a_{0}K^{+}K^{-}} and g_{f_{0}K^{+}K^{-}}, are estimated. The results improve the understanding of the nature of a_{0}^{0}(980) and f_{0}(980).

Precision Measurement of the e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} Cross Section Near Threshold

The cross section of the e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} process is measured with unprecedented precision using data collected with the BESIII detector at sqrt[s]=4574.5, 4580.0, 4590.0 and 4599.5 MeV. The nonzero cross section near the Λ_{c}^{+}Λ[over ¯]_{c}^{-} production threshold is cleared. At center-of-mass energies sqrt[s]=4574.5 and 4599.5 MeV, the higher statistics data enable us to measure the Λ_{c} polar angle distributions. From these, the Λ_{c} electric over magnetic form-factor ratios (|G_{E}/G_{M}|) are measured for the first time. They are found to be 1.14±0.14±0.07 and 1.23±0.05±0.03, respectively, where the first uncertainties are statistical and the second are systematic.

[Role of bone marrow mesenchymal stem cells with CTLA4Ig and CD40LIg gene modification in rejection reaction after liver transplantation]

Objective: To investigate the role of bone marrow mesenchymal stem cells (BMSCs) with CTLA4Ig and CD40LIg gene modification in rejection reaction after liver transplantation in rats and possible mechanisms. Methods: The modified Kamada's two-cuff technique was used to establish a Lewis-BN rat model of orthotopic liver transplantation, and a total of 75 rats were randomly divided into groups A, B, C, D, and E, with 15 rats in each group. The rats in group A (control group) were given infusion of isotonic saline via the portal vein during liver transplantation, those in group B (BMSC group) were given infusion of BMSCs via the portal vein during liver transplantation, those in group C (BMSCs with CTLA4Ig gene modification) were given infusion of BMSCs carrying the CTLA4Ig gene via the portal vein during liver transplantation, those in group D (BMSCs with CD40LIg gene modification) were given infusion of BMSCs carrying the CD40LIg gene via the portal vein during liver transplantation, and those in group E (BMSCs with CTLA4Ig and CD40LIg gene modification) were given infusion of BMSCs carrying CTLA4Ig and CD40LIg gene modification via the portal vein during liver transplantation. Postoperative survival and change in liver function were observed. HE staining was used to observe the pathomorphological changes of the graft liver, and ELISA was used to measure the levels of interleukin-2 (IL-2), interleukin-4 (IL-4), interleukin-10 (IL-10), and interferon-γ (IFN-γ) in peripheral blood. A one-way analysis of variance was used for comparison of means of multiple samples, and the Kaplan-Meier survival curve analysis was used for comparison of survival rates between multiple groups. Results: Group E had a significantly longer survival time after surgery than groups A, B, C, and D (P < 0.05), groups C and D had a significantly longer survival time than groups A and B (P < 0.05), and there was no significant difference between groups C and D (P > 0.05). On day 10 after surgery, group A had significantly higher levels of alanine aminotransferase and total bilirubin than the other four groups (P < 0.05). HE staining showed severe rejection reaction in group A, moderate rejection reaction in group B, and mild rejection reaction in groups C and D; pathological examination showed no marked rejection reaction in group E. Group A had significant increases in the levels of IL-2 and IFN-γ and significant reductions in the levels of IL-4 and IL-10 after surgery compared with the other four groups (all P < 0.05). Conclusion: Infusion of BMSCs with modification of both CTLA4Ig and CD40LIg genes can significantly inhibit acute rejection reaction after liver transplantation in rats and effectively prolong the survival time of the graft liver, with a better effect than infusion of BMSCs alone or BMSCs with modification of CTLA4Ig or CD40LIg gene.

Osteoblast differentiation of rabbit adipose-derived stem cells by polyethylenimine-mediated BMP-2 gene transfection in vitro

The aim of this study was to examine the efficiency of polyethylenimine-mediated transfection of the human bone morphogenetic protein-2 (BMP-2) gene into rabbit adipose-derived stem cells (ADSCs), and its effect on osteoblast differentiation. Adipose tissue was isolated from the necks of adult Japanese white rabbits and cultured in vitro to obtain ADSCs. Gene delivery of BMP-2 was mediated by polyethylenimine and stable transformants were selected by G-418. The expression of BMP-2 mRNA was confirmed by reverse transcription-polymerase chain reaction, and of the BMP-2 protein by ELISA. Osteocalcin and collagen type I were detected by western blot and by an alkaline phosphatase kit. Alizarin red S stain was also utilized to examine osteogenesis. The non-transfected group was considered as a control. In this study, we successfully derived ADSCs from rabbit adipose tissue. Through passages 3-6, the expression of CD29 and CD44 gradually increased, whereas the expression of CD34 and CD45 gradually decreased. Both mRNA and protein expression of BMP-2 were confirmed following polyethylenimine-mediated BMP-2 gene delivery. In addition, the expression of alkaline phosphatase, osteocalcin, and collagen type I was found to be upregulated and alizarin red S staining was positive in transfected ADSCs, indicating BMP-2-induced osteogenesis. Therefore, this study determined that polyethylenimine was able to mediate BMP-2 gene delivery and induce osteogenic differentiation of ADSCs.

Effect of compound Maqin decoction on TGF-β1/Smad proteins and IL-10 and IL-17 content in lung tissue of asthmatic rats

In this research, compound Maqin decoction (CMD) has been shown to positively affect in airway inflammation of asthma models. We evaluated the effects of CMD on the expression of transforming growth factor (TGF)-β1/Smad proteins, interleukin (IL)-17, and IL-10 in lung tissue of asthmatic rats. Asthma was induced in a rat model using ovalbumin. After a 4-week treatment with CMD, rats were killed to evaluate the expression of TGF-β1 and Smad proteins in lung tissue. IL-10 and IL-17 levels in lung tissue homogenates were determined by ELISA. The expression of TGF-β1 and Smad3 protein increased, whereas expression of Smad7 protein decreased upon high-dose or low-dose treatment with CMD or by intervention with dexamethasone, compared to the control. There was a significant difference between treatment with a high dose CMD and the control treatment, but no significant difference was found between high-dose CMD treatment and dexamethasone intervention. The expression of TGF-β1 and Smad7 protein increased, whereas the expression of Smad3 protein decreased in the model group compared to other groups. In the CMD high-dose group, low-dose group, and dexamethasone intervention group, the IL-17 concentrations in lung tissue homogenates were decreased, while IL-10 levels were increased. Again, there was a significant difference between CMD high-dose and control treatment, but not between CMD high-dose treatment and dexamethasone intervention. Thus, positive effects of CMD against asthmatic airway remodeling may be due to its regulatory effect on TGF-β1, Smad3, and Smad7 protein levels and on cytokines such as IL-10 and IL-17.

Identification of a novel LEMD3 Y871X mutation in a three-generation family with osteopoikilosis and review of the literature

INTRODUCTION

Osteopoikilosis is a rare and benign autosomal dominant genetic disorder, characterized by a symmetric but unequal distribution of multiple hyperostotic areas in different parts of the skeleton. Recent studies have reported loss-of-function mutations in the LEM domain containing 3 (LEMD3) gene, encoding an inner nuclear membrane protein, as a cause of osteopoikilosis.

METHODS

We investigated LEMD3 gene in a three-generation family from China, with six patients affected with osteopoikilosis. Peripheral blood samples were collected from family members and 100 healthy controls. All exons of the LEMD3 gene and adjacent exon-intron sequences were amplified by PCR and subsequently sequenced.

RESULTS

A novel heterozygous c.2612_2613insA (p.Y871X) mutation in exon 13 of LEMD3 was identified, which resulted in a frame shift predicted to generate a premature stop codon at amino acid position 871. The mutation co-segregates with the osteopoikilosis phenotype and was not found in 100 ethnically matched controls.

CONCLUSION

We identified a new mutation in LEMD3 gene, accounting for the familial case of osteopoikilosis. In addition we also review the clinical manifestation, diagnosis and treatment of osteopoikilosis.

Effects of washed platelets vs platelet-rich plasma on the proliferation and mineralization of rat dental pulp cells

We examined the effects of washed platelets (WPLTs) and platelet-rich plasma (PRP) on the proliferation and mineralization of rat dental pulp cells. Rat dental pulp cells were separated, cultured, and identified. Medium containing 1, 10, 100, or 500 mL/L PRP or WPLTs was added to 4th generation cells. The MTS method was used to determine cell proliferation. Alizarin red staining was used to observe the formation of mineralized nodules after cell mineralization and induction for 10 and 20 days under different culture conditions, and the areas of the mineralized nodules formed 20 days after induction were computed. The addition of 1, 10, and 100 mL/L WPLTs or PRP significantly promoted rat dental pulp cell proliferation (P < 0.05) whereas 500 mL/L WPLTs or PRP had no significant effect (P > 0.05). Under the same concentrations, no significant differences on cell proliferation were observed between WPLT and PRP treatments (P > 0.05 in all groups). After 10 days mineralization and culture, the 100 and 500 mL/L WPLT and PRP group positive nodule rates were significantly higher than those of the low concentration and the control groups (P < 0.05). After 20 days, the areas of the mineralized nodules formed in the 100 and 500 mL/L WPLT and PRP groups were significantly larger than those in the control group (P < 0.05). These results demonstrate that both WPLTs and PRP are equally able to significantly promote the proliferation and calcification of rat dental pulp cells under a certain range of concentrations.

Differential gene expression in pre-laying and laying period ovaries of Sichuan White geese (Anser cygnoides)

Geese are an economically important poultry species worldwide. Their superior meat production performance and meat qual-ity make them a popular food. However, they are not bred worldwide because their poor laying capacity increases farming costs. To gain a global view of the genes that are differentially expressed between pre-laying (P) and laying (L) periods and to develop a database for further studies, we performed large-scale transcriptome sequencing of ovarian tissue collected from Anser cygnoides. In total, 30,151,422 raw reads, with an average length of 151 bp and a total length of 4,552,864,722 bp, were obtained. After primers and adaptors were removed, 19,167,132 clean reads, with an average length of 134.5 bp and a total length of 2,577,297,281 bp, were obtained, among which 1,268,906,694 bp and 1,308,390,587 bp were from L and P ovarian tissue, respectively. The 16,605 assembled sequences were further functionally annotated by comparing their sequences to different protein and functional domain databases and assigning gene ontology (GO) terms. Of these, 511 as-sembled sequences were considered differentially expressed based on the 2-fold method, among which 396 were assigned at least one GO term. Digital expression analysis using the Kyoto encyclopedia of genes and genomes annotation identified 121 genes that were differ-entially expressed in the P vs L periods. Five of these are of special interest for further investigation of their roles in determining high re-productive performance. This study provides valuable information and sequence resources for uncovering genes determining high egg-laying performance and for future functional genomics analysis of geese.

Note: A new regulation method of stable operation of high power cathode ion source

The hot cathode ion source will tend to be unstable when operated with high power and long pulse. In order to achieve stable operation, a new regulation method based on the arc power (discharge power) feedback control was designed and tested on the hot cathode ion source test bed with arc discharge and beam extraction. The results show that the new regulation method can achieve stable arc discharge and beam extraction. It verifies the success of feedback control of arc source with arc power.

Treatment of domestic sewage by a metal membrane bioreactor

A submerged flat metal MBR (membrane bioreactor) was used to treat synthetic domestic sewage in this study. The experiment was continued for 270 days and ran under two modes as AMBR (aerobic membrane bioreactor) and A/O-MBR (anoxic/aerobic membrane bioreactor) at a permeate flux of 0.4-1 m³/(m² d). PVA (polyvinyl alcohol) gel beads were added to the aeration tank with a volume ratio of 10% at the end of the A/O-MBR mode. The mean COD and TN removal efficiencies achieved 96.69 and 32.12% under the AMBR mode, and those were 92.17 and 72.44% under the A/O-MBR mode, respectively. SND (simultaneous nitrification and denitrification) occurred at high MLSS (mixed liquor suspended solids) concentration. The metal membranes reduced effluent COD during filtration. The system ran stably for 115 days at a permeate flux of 0.8-1 m³/(m² d) without changing membranes under the AMBR mode, but the membrane filterability decreased gradually under high MLSS or A/O-MBR mode, and the addition of PVA worsened the membrane filterability on the contrary. PSD (particle size distribution) and sludge fractions had evident influence on membrane fouling. The main fouling mechanism was cake formation under the AMBR mode, and that was pore blocking under the A/O-MBR mode.

Termination of two-dimensional metallic conduction near the metal-insulator transition in a Si/SiGe quantum well

We report in this Letter our recent low-temperature transport results in a Si/SiGe quantum well with moderate peak mobility. An apparent metal-insulating transition is observed. Within a small range of densities near the transition, the conductivity σ displays a nonmonotonic temperature dependence. After an initial decrease at high temperatures, σ first increases with decreasing temperature T, showing a metallic behavior. As T continues decreasing, a downturn in σ is observed. This downturn shifts to a lower T at higher densities. More interestingly, the downturn temperature shows a power-law dependence on the mobility at the downturn position, suggesting that a similar downturn is also expected to occur deep in the apparent metallic regime at albeit experimentally inaccessible temperatures. This thus hints that the observed metallic phase in 2D systems might be a finite temperature effect.

Comparative study of polyvinylidene fluoride and PES flat membranes in submerged MBRs to treat domestic wastewater

Two kinds of membranes, polyvinylidene fluoride (PVDF) and polyethersulfone (PES), were used in submerged flat membrane bioreactors (MBRs) to treat domestic wastewater in this study. The MBRs ran under the same reactor structure, the same membrane pore size of 0.45 mICROm and the same anoxic/ oxic (A/O) process. The experimental results showed that: (1) With the influent of BOD(5) 200-500 mg/L and COD(Cr) 400-1,000 mg/L, PVDF MBR achieved the removal efficiencies of BOD(5) 96-98% and COD(Cr) 89-98%, and those were 97-99% and 93-97% in PES MBR. The interceptive efficiency of PES membrane to BOD(5) and COD(Cr) was superior to PVDF membrane. (2) The removal efficiencies of TN and NH(3)-N in two MBRs exhibited good results which were greater than 85%. The removal efficiencies of TP were greater than 80% in both MBRs. (3) MLSS concentration changed from 2,000 mg/L to 7,000 mg/L during the experiment. PES membrane was not washed and the membrane flux was steady. However, the flux of PVDF one decreased quickly and was washed for twice. It meant that PES membrane had fine capability than PVDF one.

Pharmacological studies of the large-scaled purified genistein from Huaijiao (Sophora japonica-Leguminosae) on anti-osteoporosis

In this report, we used genistein that was extracted from a Chinese herbal medicine Huaijiao (Sophora japonica-Leguminosae) to evaluate its pharmacological function on anti-osteoporosis. This genistein is purified in a large-scale production from Huaijiao by a state-of-art method as described by Tian et al. [2004. The preparation of genistein and LC-MS/MS on-line analysis. Drug Devel. Res. 61, 6-12]. Chemical structure of the isolated genistein was examined by using various techniques including nuclear magnetic resonant spectrum, infrared absorption spectrum, ultraviolet absorption spectrum and mass spectrum, and was proved to be identical to those purified from soybean in a small scale as previously reported. We randomly divided female SD rats into 6 groups, including control, ovariectomized model, Nilestriol-treated, and three level of dosages of genistein-treated. We evaluated the pharmacological effects of genistein against osteoporosis by measuring the bone density of femur and bone mineral group including calcium, phosphorous, and magnesium. The consequences of genistein treatment on bone histology and morphology were also determined by measuring the trabcular area, thickness and number. Our results indicated that treatment with a 4.5 or 9 mg/kg dosage of genistein could also prevent osteoporosis significantly at the 4th week after treatment. In comparison with the anti-osteoporosis effects of soybean genistein, the genistein extracted from Huaijiao has the same beneficial effect on anti-osteoporosis.

A comparative approach to somatic cell nuclear transfer in the rhesus monkey

BACKGROUND

Despite the potential utility of primate somatic cell nuclear transfer (SCNT) to biomedical research and to the production of autologous embryonic stem (ES) cells for cell- or tissue-based therapy, a reliable method for SCNT is not yet available. Employing the rhesus monkey as a clinically relevant animal model, we have compared a conventional electrofusion method for SCNT with a one-step micromanipulation (OSM) method.

METHODS

A prospective, randomized trial was conducted using only oocytes that were mature [metaphase II (MII)] at collection and a fibroblast-like cell line as nuclear donor cells (fetal fibroblasts). The embryos produced were characterized for in vitro developmental potential, cell number, karyotype and expression of nuclear mitotic apparatus (NuMA) and OCT-4.

RESULTS

An in vitro blastocyst development rate of 24.4% was achieved with the OSM method, significantly higher than the 12.2% obtained following electrofusion. SCNT-produced embryos expressed normal karyotypes, cell numbers and NuMA and OCT-4 proteins in most cases. SCNT with male nuclear donor cells resulted in the production of male, SCNT blastocysts, eliminating the possibility of a parthenogenetic origin. Of the four fibroblast cell lines tested as nuclear donor cells, two supported the routine production of blastocysts following SCNT.

CONCLUSIONS

The application of a modified SCNT technique (OSM) followed by embryo culture in hamster embryo culture medium-10 (HECM-10) allows, for the first time, the routine production of SCNT blastocysts, most of which appear normal by immunochemical, cytochemical and in vitro developmental criteria. These embryos will provide a resource for isolating ES cells and for studies of nuclear reprogramming by monkey cytoplasts.

Characterization of the genomic structure and tissue-specific promoter of the human nuclear receptor NR5A2 (hB1F) gene

The human homologue of the Drosophila melanogaster orphan nuclear receptor fushi tarazu factor 1 (Ftz-F1), NR5A2 (hB1F), was initially identified as a regulatory factor that binds and activates enhancer II of hepatitis B virus. NR5A2 (hB1F) is expressed specifically in pancreas and liver, playing important roles in the regulation of several liver-specific genes. A detailed analysis on the genomic structure and promoter activity will greatly promote future studies on the function of the NR5A2 (hB1F) gene. In this report, a bacterial artificial chromosome clone and several phage clones covering the NR5A2 (hB1F) gene were isolated and the complete genomic sequence was obtained. Alignment of different cDNAs of the NR5A2 (hB1F) gene with the genomic sequence facilitated the delineation of its structural organization, which spans over 150 kb and consists of eight exons interrupted by seven introns. RT-PCR and 3'-RACE revealed that utilization of two polyadenylation signals results in the 3.8 and 5.2 kb transcripts that were observed previously. The transcription start site of the NR5A2 (hB1F) gene was mapped downstream of a canonical TATA box. An upstream fragment containing binding sites for several liver-specific and ubiquitous transcription factors exhibits hepatocyte-specific promoter activity. Transient transfections indicated that hepatocyte nuclear factors HNF1 and HNF3beta could activate NR5A2 (hB1F) promoter.

Subcellular localization of the Agrobacterium tumefaciens T-DNA transport pore proteins: VirB8 is essential for the assembly of the transport pore

Agrobacterium tumefaciens transforms plants by transferring DNA to the plant cell nucleus. The VirB membrane proteins are postulated to form a pore for the transport of the DNA across the bacterial membranes. Immunofluorescence and immunoelectron microscopy were used to study the transport pore complex. Three likely components of the transport pore, VirB8, VirB9 and VirB10, localized primarily to the inner membrane, outer membrane and periplasm respectively. A significant amount of VirB10 was also found associated with the outer membrane. When expressed alone VirB9 and VirB10 were randomly distributed along the cell membrane. Subcellular location of both proteins changed dramatically in the presence of the other VirB proteins. Both proteins localized to fewer sites and most of the gold particles representing protein molecules were found in clusters suggesting that the two proteins are in a protein complex. VirB8, on the other hand, localized to clusters even in the absence of the other VirB proteins. To investigate the role of VirB8 in the formation of VirB9 and VirB10 protein complexes, we studied the effect of deletion of virB8 on the subcellular location of VirB9 and VirB10. In a virB8 deletion mutant both proteins were distributed randomly on the cell membrane indicating that VirB8 is essential for complex assembly.

The Agrobacterium T-DNA transport pore proteins VirB8, VirB9, and VirB10 interact with one another

The VirB proteins of Agrobacterium tumefaciens form a transport pore to transfer DNA from bacteria to plants. The assembly of the transport pore will require interaction among the constituent proteins. The identification of proteins that interact with one another can provide clues to the assembly of the transport pore. We studied interaction among four putative transport pore proteins, VirB7, VirB8, VirB9 and VirB10. Using the yeast two-hybrid assay, we observed that VirB8, VirB9, and VirB10 interact with one another. In vitro studies using protein fusions demonstrated that VirB10 interacts with VirB9 and itself. These results suggest that the outer membrane VirB7-VirB9 complex interacts with the inner membrane proteins VirB8 and VirB10 for the assembly of the transport pore. Fusions that contain small, defined segments of the proteins were used to define the interaction domains of VirB8 and VirB9. All interaction domains of both proteins mapped to the N-terminal half of the proteins. Two separate domains at the N- and C-terminal ends of VirB9 are involved in its homotypic interaction, suggesting that VirB9 forms a higher oligomer. We observed that the alteration of serine at position 87 of VirB8 to leucine abolished its DNA transfer function. Studies on the interaction of the mutant protein with the other VirB proteins showed that the VirB8S87L mutant is defective in interaction with VirB9. The mutant, however, interacted efficiently with VirB8 and VirB10, suggesting that the VirB8-VirB9 interaction is essential for DNA transfer.

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.

Cloning and characterization of a novel human hepatocyte transcription factor, hB1F, which binds and activates enhancer II of hepatitis B virus

Enhancer II (ENII) of hepatitis B virus (HBV) is one of the essential cis-elements for the transcriptional regulation of HBV gene expression. Its function is highly liver-specific, suggesting that liver-enriched transcriptional factors play critical roles in regulating the activity of ENII. In this report, a novel hepatocyte transcription factor, which binds specifically to the B1 region (AACGACCGACCTTGAG) within the major functional unit (B unit) of ENII, has been cloned from a human liver cDNA library by yeast one-hybrid screening, and demonstrated to trans-activate ENII via the B1 region. We named this factor hB1F, for human B1-binding factor. Amino acid analysis revealed this factor structurally belongs to nuclear receptor superfamily. Based on the sequence similarities, hB1F is characterized to be a novel human homolog of the orphan receptor fushi tarazu factor I (FTZ-F1). Using reverse transcription-polymerase chain reaction, a splicing isoform of hB1F (hB1F-2) was identified, which has an extra 46 amino acid residues in the A/B region. Examination of the tissue distribution has revealed an abundant 5.2-kilobase transcript of hB1F is present specifically in human pancreas and liver. Interestingly, an additional transcript of 3.8 kilobases was found to be present in hepatoma cells HepG2. Fluorescent in situ hybridization has mapped the gene locus of hB1F to the region q31-32.1 of human chromosome 1. Altogether, this study provides the first report that a novel human homolog of FTZ-F1 binds and regulates ENII of HBV. The potential roles of this FTZ-F1 homolog in tissue-specific gene regulation, in embryonic development, as well as in liver carcinogenesis are discussed.