Vacuum ultraviolet laser pulsed field ionization-photoelectron study ofcis-dichloroethene

The vacuum ultraviolet (VUV) laser pulsed field ionization photoelectron (PFI-PE) spectrum of cis-dichloroethene (cis-ClCH[Double Bond]CHCl) has been measured in the energy region of 77 600-79 500 cm(-1). On the basis of the semiempirical simulation of the origin PFI-PE band, we have obtained the IE(cis-ClCH[Double Bond]CHCl) to be 77 899.5+/-2.0 cm(-1) (9.658 39+/-0.000 25 eV). The assignment of the vibrational bands resolved in the VUV-PFI-PE spectrum are guided by high-level ab initio calculations of the vibrational frequencies for cis-ClCH[Double Bond]CHCl(+) and the Franck-Condon factors for the ionization transitions. Combining the results of the present VUV-PFI-PE measurement and the recent VUV-infrared-photoinduced Rydberg ionization study, the vibrational frequencies for eleven of the twelve vibrational modes of cis-ClCH[Double Bond]CHCl(+) have been experimentally determined: nu(1) (+)(a(1))=181 cm(-1), nu(2) (+)(a(2))=277 cm(-1), nu(3) (+)(b(2))=580 cm(-1), nu(4) (+)(b(1))=730 cm(-1), nu(5) (+)(a(1))=810 cm(-1), nu(6) (+)(a(2))=901 cm(-1), nu(8) (+)(a(1))=1196 cm(-1), nu(9) (+)(b(2))=1348 cm(-1), nu(10) (+)(a(1))=1429 cm(-1), nu(11) (+)(b(2))=3067 cm(-1), and nu(12) (+)(a(1))=3090 cm(-1)). These values are compared to theoretical anharmonic vibrational frequencies obtained at the MP2/6-311G(2df,p) and CCSD(T)/6-311G(2df,p) levels. The IE prediction for cis-ClCH[Double Bond]CHCl has also been calculated with the wave function based CCSD(T)/CBS method, which involves the approximation to the complete basis set (CBS) and the high-level correlation corrections. The theoretical IE(cis-ClCH[Double Bond]CHCl)=9.668 eV thus obtained is found to have a deviation of less than 10 meV with respect to the experimental IE value.

Synthesis and electrical properties of ZnO nanowires

Vertically aligned ZnO nanowires were synthesized on the p(+) silicon chip by modifying the CVD process with a vapor trapping design. Scanning electron microscopy was used to investigate the morphology of as-obtained nanowires. X-ray diffraction showed that the obtained nanowires were ZnO crystalline. The rectifying characteristics of the p-n heterojunction composed of ZnO nanowires and a p(+) silicon chip were observed. The positive turn-on voltage was 0.5V and the reverse saturation current was 0.01mA. These vertically aligned ZnO nanowires showed a low field emission threshold of 4V/microm at a current density of 0.1microA/cm(2). The dependence of emission current density on the electric field followed Fowler-Nordheim relationship.

Infrared vibrational spectroscopy of cis-dichloroethene in Rydberg states

We have measured the infrared (IR) vibrational spectrum for cis-dichloroethene (cis-ClCH[Double Bond]CHCl) in excited Rydberg states with the effective principal quantum numbers n(*)=9, 13, 17, 21, 28, and 55 using the vacuum ultraviolet-IR-photoinduced Rydberg ionization (VUV-IR-PIRI) scheme. Although the IR frequencies observed for the vibrational bands nu(11) (*) (asymmetric C-H stretch) and nu(12) (*) (symmetric C-H stretch) are essentially unchanged for different n(*) states, suggesting that the IR absorption predominantly involves the ion core and that the Rydberg electron behaves as a spectator; the intensity ratio for the nu(11) (*) and nu(12) (*) bands [R(nu(11) (*)nu(12) (*))] is found to decrease smoothly as n(*) is increased. This trend is consistent with the results of a model ab initio quantum calculation of R(nu(11) (*)nu(12) (*)) for excited cis-ClCH[Double Bond]CHCl in n(*)=3-18 states and the MP26-311++G(2df,p) calculations of R(nu(11)nu(12)) and R(nu(11) (+)nu(12) (+)), where R(nu(11)nu(12))[R(nu(11) (+)nu(12) (+))] represents the intensity ratio of the nu(11)(nu(11) (+)) asymmetric C-H stretching to the nu(12)(nu(12) (+)) symmetric C-H stretching vibrational bands for cis-ClCH[Double Bond]CHCl (cis-ClCH[Double Bond]CHCl(+)). We have also measured the IR-VUV-photoion (IR-VUV-PI) and IR-VUV-pulsed field ionization-photoelectron depletion (IR-VUV-PFI-PED) spectra for cis-ClCH[Double Bond]CHCl. These spectra are consistent with ab initio calculations, indicating that the IR absorption cross section for the nu(12) band is negligibly small compared to that for the nu(11) band. While the VUV-IR-PIRI measurements have allowed the determination of nu(11) (+)=3067+/-2 cm(-1), nu(12) (+)=3090+/-2 cm(-1), and R(nu(11) (+)nu(12) (+)) approximately 1.3 for cis-ClCH=CHCl(+), the IR-VUV-PI and IR-VUV-PFI-PED measurements have provided the value nu(11)=3088.5+/-0.2 cm(-1) for cis-ClCH=CHCl.

Morphology investigation of Ag(TCNQ) synthesized by the vapor-transport reaction method

Ag(TCNQ) nanostructures with wire-, belt- and flower-like morphologies have been prepared on Si wafers by a vapor-transport reaction between silver and TCNQ without additional catalyst. The morphologies were characterized by SEM and optical microscopy. The composition of nanowires was tested by Raman spectroscopy. The growth mechanism of different morphologies based on the VS mechanism is emphasized.

Microscopy investigation of Ag-TCNQ micro/nanostructures synthesized via two solution routes

The micro/nanostructures of metal-organic complex Ag-TCNQ were successfully synthesized by the reaction between Ag film and TCNQ dissolved in acetonitrile via two solution routes, i.e. immerging and dipping reaction. X-ray diffraction confirmed that the obtained Ag-TCNQ micro/nanostructures were crystalline. The morphology of the as-grown structures varied from straight nanowires and microtubes to complex fractals and dendrites. The growth mechanism of the mainly dendrites may be considered within the framework of DLA model.

Scanning electron microscopy investigation of Cu–TCNQ micro/nanostructures synthesized via vapor-induced reaction method

Micro/nanostructures based on the metal-organic complex Cu-TCNQ were successfully synthesized by a novel method: vapor-induced reaction. Scanning electron microscopy was used to investigate the morphology on the three different parts of the substrate: the hot reaction area, a transitional reaction area and an induced reaction area. The results show that the morphology of the as-grown structures evolves from microstructures to nanostructures. The formation mechanism of these different structures may be understood from electrochemical principles and the decreasing concentration of TCNQ.

Characterization of the promoter of 1A6/DRIM, a novel cancer-related gene and identification of its transcriptional activator

1A6/DRIM (Down-regulated in Metastasis) has been reported to express at a high level in the gastric cancer tissues and the premalignant lesions implicating the involvement of 1A6/DRIM in cell transformation. Although the information regarding the putative functions and distribution of the 1A6/DRIM in different tissues and cell lines has been increasing recently, its promoter and promoter-regulating factors remain unknown. In this study, the transcription initiation site of 1A6/DRIM was confirmed to be located at 147 bp upstream of the ATG codon using the primer extension analysis. The minimal promoter region of the 1A6/DRIM is located between -47 and +42 of the transcription initiation site measured by luciferase reporter assays using a set of deletion constructs. In addition, an E-box is shown to be an essential element for transcriptional regulation of 1A6/DRIM demonstrated by luciferase assay with different deletion and mutation constructs. Finally, a transcription factor, upstream stimulatory factor 2 (USF2) was found to be an activator of the 1A6/DRIM through binding to the E-box demonstrated by luciferase reporter assay, electrophoretic mobility shift assay, and chromatin immunoprecipitation (ChIP) assay. The structural analysis of the 1A6/DRIM promoter and the identification of its potential regulatory effecter may help us to understand its biological functions in regulating cancer development.

Rovibrational-state-selected pulsed field ionization-photoelectron study of methyl iodide using two-color infrared-vacuum ultraviolet lasers

The preparation of methyl iodide (CH(3)I) in selected rovibrational states [nu(7)=1 (C-H stretch); J] by infrared (IR) excitation prior to vacuum ultraviolet (VUV) photoionization has greatly simplified the observed pulsed field ionization-photoelectron (PFI-PE) spectra, allowing the direct determination of the rotational constants B(+)(C(+))=0.254+/-0.003 cm(-1) for CH(3)I(+)(X (2)E(3/2);nu(7) (+)) and the ionization energy (76 896.9+/-0.2 cm(-1)) for CH(3)I(+)(X (2)E(3/2);nu(7) (+)=1,J(+)=3/2)<--CH(3)I(X (1)A(1);nu(7)=1,J=0). The IR-VUV-PFI-PE and IR-VUV-photoion measurements also provide relative state-to-state (nu(7) (+)=1, J(+)<--nu(7)=1, J) cross sections for the photoionization process.

Single-photon vacuum-ultraviolet laser-pulsed-field ionization-photoelectron studies of trans- and cis-1-bromopropenes

The vacuum-ultraviolet (VUV) pulsed-field ionization-photoelectron (VUV-PFI-PE) spectra of trans-1-bromopropene (trans-CH(3)CH[Double Bond]CHBr) and cis-1-bromopropene (cis-CH(3)CH[Double Bond]CHBr) have been measured in the energy region of 74 720-76 840 cm(-1). The simulation of fine structures observed in the origin VUV-PFI-PE vibrational bands of these molecules has provided the ionization energies (IEs) of trans-1-bromopropene and cis-1-bromopropene to be 74 779.3+/-2.0 cm(-1) (9.2715+/-0.0002 eV) and 75 140.2+/-2.0 cm(-1) (9.3162+/-0.0002 eV), respectively. The vibrational bands resolved in these VUV-PFI-PE spectra at energies 0-1700 cm(-1) above the IEs of trans-1-bromopropene and cis-1-bromopropene have been assigned based on theoretical vibrational frequencies and calculated Franck-Condon factors for the ionization transitions.

Vacuum ultraviolet-infrared photo-induced Rydberg ionization spectroscopy: C–H stretching frequencies for trans-2-butene and trichloroethene cations

We have demonstrated the two-color vacuum ultraviolet (VUV)-infrared (IR) photoinduced Rydberg ionization (PIRI) experiment. Trichloroethene (ClCH=CCl2) and trans-2-butene (trans-CH3CH=CHCH3) were prepared in Rydberg states in the range of effective principal quantum number n* approximately 7-93 by VUV excitation prior to IR-induced autoionization. The observed VUV-IR-PIRI spectra are found to be independent of n*, suggesting that the electron Rydberg orbital is conserved, i.e., the Rydberg electron is behaving as a spectator during the excitation process. The observed IR active C-H stretching vibrational frequencies nu12+ = 3072+/-5 cm(-1) for ClCH=CCl2+ and nu23+ =2908+/-3 cm(-1), nu25+ =2990+/-10 cm(-1) and nu30+ =3022+/-10 cm(-1) for trans-CH3CH=CHCH3+ are compared with predictions based on ab initio quantum-chemical procedures and density functional calculations.

[Chromosome localization of the dentinogenesis imperfecta type II locus]

OBJECTIVE

To investigate the linkage between dentinogenesis imperfecta type II and chromosome 4q21 in a Tianjin-Tanggu family of the Hui nationality.

METHODS

Blood samples were collected from 13 family members. DNAs were analyzed with 8 STRP markers (D4S2915, D4S2932, GATA62A11, D4S2409, DSP STRP, SPP1 STRP, D4S1563, D4S1544) using fluorescence-based PCR. The linkage between eight markers on chromosome 4q21 and dentinogenesis imperfecta type II locus was tested respectively by lod score analysis.

RESULTS

Genotype and haplotype were acquired. Genetic linkage analysis demonstrated the maximum lod score of eight STRPs were all larger than zero, in which five of them were larger than 1.

CONCLUSION

The locus of dentinogenesis imperfecta type II in Chinese family is located on human chromosome 4q21, which indicated that the locus of Chinese Hui nationality should be the same as that of other reported European or American family.

Obesity, coronary heart disease risk factors and diabetes in Chinese: an approach to the criteria of obesity in the Chinese population

The aim of this work was to study the relationship between excess body weight and the risks of hypertension and diabetes in the population of northeastern China. Subsections of a cross-sectional survey in Da Qing City were used to assess the relationship of excess weight to risk factors for coronary heart disease (CHD). A 6-year prospective study also assessed the probability of developing Type 2 diabetes. A total of 2856 adults (25-70 years of age) were assessed cross-sectionally and 629 non-diabetic subjects of similar age were followed-up for 6 years. Blood pressure, plasma fasting glucose, triglycerides, high-density lipoporotein (HDL) cholesterol and fibrinogen levels were measured as well as weight, height and waist and hip circumferences. About 45% of adults had a body mass index (BMI) of > or =25.0. Risk factors increased with increasing BMI from a baseline value of 21.0: at a BMI of 23.0-24.9, the risk of hypertension and hypertriglyceridaemia doubled; the risk increased threefold at a BMI of 25.0-26.9. The prevalence of Type 2 diabetes increased progressively in women within the normal BMI range and in men from a BMI of 25.0. Type 2 diabetes was four times as common if the BMI was >27.0. Increasing waist measurements predicted 10-fold increases in hypertension and a three-to-five times increased risk of diabetes. Suitable waist cut-off points were 85cm for men and 80cm for women, with statistical analysis showing waist as the more dominant predictor of risk than age, waist-to-hip ratios or BMIs. Hence, small increases in BMI, and particularly in waist circumference, predict a substantial increase in the risk of diabetes and risk for CHD, especially hypertension, in Chinese adults.

[The efficacy and safety of pioglitazone hydrochloride in combination with sulphonylureas and metfomin in the treatment of type 2 diabetes mellitus a 12-week randomized multi-centres placebo-controlled parallel study]

OBJECTIVE

To evaluate the efficacy and safety of pioglitazone hydrochloride 30 mg/day with sulphonylureas and metfomin in the treatment of patients with type 2 diabetes mellitus.

METHODS

There were 283 patients treated with sulphonylureas and metfomin randomized in this multicenter double-blind placebo-controlled clinical trial. Patients who had 7.0 mmol/L </= fasting plasma glucose(FPG) < 13.0 mmol/L were randomized to receive placebo or pioglitazone 30 mg once daily for 12 weeks.

RESULTS

The patients who had been treated with pioglitazone 30 mg showed significant decrease on average from baseline in FPG(1.1 mmol/L versus 0.4 mmol/L, P < 0.001), postprandial plasma glucose(PPG,1.5 mmol/L versus 0.3 mmol/L, P < 0.001), and glycosylated hemoglobin (HbA1c, 0.7% versus 0.4%, P < 0.01). AS for fasting plasma insulin (FIns) levels decreased, significant difference was also observed in the two groups (P < 0.05). HOMA-IR had significant mean decrease in the pioglitazone group as compared with placebo group (P < 0.01).

CONCLUSION

Pioglitazone 30 mg/day for 12 weeks might improve the metabolic control and the insulin sensitivity in poorly controlled type 2 diabetes with previous administration of sulphonylureas and metfomin. It provides a safety and tolerance profile for type 2 diabetes mellitus in this trial.

Pharmacological differences between immunoisolated native brain and heterologously expressed rat alpha4beta2 nicotinic receptors

Native brain and heterologously expressed rat alpha4beta2 nicotinic receptors (in Xenopus oocytes and CV-1 cells) were immunoisolated with the anti-alpha4 antibody mAb 299 and their pharmacological properties were compared using [3H](+/-)epibatidine, the novel N-alkylnicotinium analog N-n-octylnicotinium iodide (NONI), and the ganglionic antagonist trimethaphan (TRM). The equilibrium dissociation constant (K(d)) for [3H](+/-)epibatidine binding to the native and heterologously expressed receptors ranged from 13 to 21 pM. The Hill coefficients for [3H](+/-)epibatidine binding to the native and expressed receptors ranged from 0.8 to 1.1 and were consistent with a single high-affinity site. NONI inhibited 30 pM [3H](+/-)epibatidine binding to the native and expressed receptors with similar potency (IC(50) values of 6-7 microM). However, [3H](+/-)epibatidine dissociated 2-3 times more slowly from the native, than from the expressed receptors and TRM inhibited 30 pM [3H](+/-)epibatidine binding to the native receptors (IC(50) value of 330 microM) less potently than it did to the receptors expressed in oocytes (IC(50) value of 16 microM) or CV-1 cells (IC(50) value of 55 microM). The differences between the native and expressed [3H](+/-)epibatidine dissociation rate constants and IC(50) values for TRM were significant for both host cell types, although the values for the CV-1-expressed receptors were closer to the native ones than were those for the oocyte-expressed receptors. Thus, the epibatidine and trimethaphan binding sites in native and expressed alpha4beta2 receptors appear to have significantly different structural or chemical properties.

[Effects of estradoil valerate on osteoporosis in ovariectomized rats]

OBJECTIVE

Compared with 17beta-estradiol, to evaluate the effects of estradiol valerate on osteopenia in ovariectomized rats.

METHODS

Forty two six months old female Wistar rats were randomly divided into 5 groups performed ovariectomy (OVX) or sham-operation. (1) 6 weeks after OVX (Ovxb, n = 8): sacrificed at 6 weeks after OVX; (2) Sham ovariectomized (n = 8); (3) 14 weeks after OVX (Ovxe, n = 8); (4) 17beta-estradoil treated group (O + E, n = 9, with 17beta-estradiol 20 microg x kg(-1) x d(-1) Sc.); (5) Estradoil valerate treated group (O + EV, n = 9, with estradiol valerate 800 microg x kg(-1) x d(-1) po). Treatment started 6 weeks after OVX and lasted for 8 weeks. Histomorphometry analysis of tibia, peripheral quantitative computed tomography (pQCT) scanning of femur, bone biomechanical test in femur were performed.

RESULTS

OVX induced osteopenia and increase of bone turnover. Compared with Ovxe, O + E and O + EV caused an evident reduction of urinary deoxypyridinoline/creatinine, a bone resorption marker, by 54.6% and 77.4% respectively (all P < 0.01). Both O + E and O + EV lowered the high level of eroded surface, mineral surface and bone formation rate induced by OVX. An increase of 122.3% and 119.7% in trabecular bone volume respectively in O + E and O + EV group, compared with Ovxe group. Microarchitecture of trabeculea also improved in those two groups. The trabeculae bone mineral density determined by pQCT were significantly increased in O + E and O + EV compared with Ovxe group (99.5% and 128.4% P < 0.01). Similarly, significant increases were found in cancellouse maximal load and canceallous stiffness of distal femur in O + E, but not O + EV. There was no significant difference in these changes between the group O + E and O + EV.

CONCLUSION

Oral estradiol valerate performed effects similar to those of 17beta-estradiol Sc. in inhibiting bone turnover, protecting bone loss and increasing bone mineral density of trabecular bone.

[The application of air-lift loop column filling with porous carrier in wastewater treatment]

An air lift loop reactor filling with porous carrier particles was utilized as aeration column. Experiments were carried out in wide operating conditions. The experimental results showed that in the range of gas flow rate from 0.117 to 0.156 m3/(min.m3), a higher efficiency of removal of ammonium-N was achieved, and when the gas flow rate was above 0.039 m3/(min.m3), the COD was completely degraded in about 1 h. The filling ratio of the porous carriers in the column was an important factor for the removal of C and N compounds, and a filling ratio of 15% was proved to be most suitable in the operation ranges. The experimental results also indicated that the effect of aeration temperature on the removal efficiency was significant and the highest efficiency was obtained at around 25 degrees C.

[Reconstruction of digital avulsion with pre-fabricated subdermal vascular network skin flap by ultrasonic liposuction]

OBJECTIVE

To investigate the clinical application of subdermal vascular network skin flap pre-fabricated by ultrasonic liposuction in reconstruction of digital avulsion.

METHODS

Forty-seven injured fingers of 23 cases were treated from June 1997 to February 2000. Conventional abdominal skin flap was elevated, according to the size of digital avulsion, and subcutaneous fat was removed with scissors. Ultrasonic liposuction technology was adopted, in order to minimize the injury of subdermal vascular vessels, to remove the fat particles close to the vascular network. Finally, the pre-fabricated skin flap was used to repair the digital avulsion. The vascular pedicle was severed in 5 to 7 days after operation. The range of skin flap was 4 cm x 3 cm to 8 cm x 7 cm, and the ratio of length and width was (2 to 3) to 1.

RESULTS

All the skin flaps were survived. Twenty-one patients were available for postoperative follow-up for 6 to 24 months. The motion of interphalangeal joint achieved functional recovery, and the sensation of pain, temperature and taction recovered well.

CONCLUSION

Ultrasonic liposuction does not obviously injure the subdermal vascular network skin flap, it is a simple and safe method for treatment of digital avulsion.

[Effect of grazing rate on biomass and element composition of Xanthoparmelia camtschadalis]

Xanthoparmelia camtschadalis is widely distributed in grassland area of Mongolian Plateau. There are few studies on the relationships between biomass, element composition and stocking rate. The relationships of biomass and element composition of Xanthoparmelia camtschadalis to grazing rates in Leymus chinensis steppe in Inner Mongolia were investigated. The results indicated that the biomass of the lichen was highest under light grazing, while the lowest under extremely overgrazing treatment. The C, N and Ca concentrations were higher than 1%, P, Mg, K and Fe were between 0.1% and 1%, and Na, Mn, Cu, Zn, and B were less than 0.1%. The Ca content in Xanthoparmelia camtschadalis was much higher than that in vascular plant. With an increasing grazing rate, the C concentration decreased, while N increased. The C/N ratio was the lowest under moderate and heavy grazing treatments. Ca, Mg, K, Fe, Mn and Cu contents were higher under grazing treatments. The changes of biomass and element composition of Xanthoparmelia camtschadalis had a good response to grazing rate, and hence, it was a good indicator to indicate the healthy condition and changes of biogeochemistry cycles in grassland ecosystems.

A Novel Synthesis of Enantiomerically Pure 5,5,5,5‘,5‘,5‘-Hexafluoroleucine

[reaction in text] A novel, short, and efficient synthesis of (S)-5,5,5,5',5',5'-hexafluoroleucine (6) in greater than 99% ee starting from the protected oxazolidine aldehyde 1 is described. The enantiomeric excess of the product was calculated from an NMR analysis of a dipeptide formed by reaction with a protected L-serine derivative. Furthermore, a racemic sample of N-acylated hexafluoroleucine was enzymatically resolved by treatment with porcine kidney acylase I and was found to have the same optical rotation as a synthetic sample of 6.

[An experimental study on the construction of composite graft with epithelia and fibroblasts on collagen sponge]

OBJECTIVE

Primarily cultured human epithelia and fibroblasts were inoculated on collagen sponge to construct composite skin substitute.

METHODS

Epithelia and fibroblast asts from human foreskin were primarily cultured. Fibroblasts (1 x 10(5)/cm(2)) were inoculated on collagen sponge after digestion and cultured for 3 days prior to inoculation of epithelial cells (2 x 10(5)/cm(2)) to construct composite skin grafting substitute, and it was then grafted onto full skin loss (FSL) wounds of nude mice. Collagen sponge membrane lacking cell inoculation was used as control. The wound healing was evaluated by measuring the residual wound area. Tissue samples were harvested and examined by means of histology, immunohistochemistry and electron microscopy.

RESULTS

Epithelia and fibroblasts could be cultured in vitro on the carrier collagen sponge. After being grafted onto the wound, the epithelia and fibroblasts wound further proliferated and differentiated. The composite skin could stick to the carrier fairly well. There exhibited less epidermal scar proliferation and satisfactory contour of the neoskin. Integral basal membrane of the skin could be identified by immunohistochemical staining. The quality and speed of wound healing with the composite skin substitute were superior to that with collagen sponge only.

CONCLUSION

The composite grafts constructed by epithelia and fibroblasts on collagen sponge could be a potential neotype composite skin substitute for the repair of FSL.

[Clinical observation of phacoemulsification with foldable intraocular lens implantation through a limbus incision]

OBJECTIVE

To investigate the clinical therapeutic effects of phaco-emulsification with foldable intraocular lens implantation through a limbus tunnel incision.

METHODS

Eighty-six patients (107 eyes) with senile cataract underwent phacoemulsification with acrylic foldable posterior chamber intraocular lens implantation through a 4 mm superior limbus tunnel incision.

RESULTS

The corrected visual acuity of 0.5 or better was 62.6% at the 1st day, and 76.6%, 92.5% and 88.8% respectively at the 1st week, 1st month and 3rd month postoperatively.

CONCLUSION

Phacoemulsification with foldable intraocular lens implantation through a limbus tunnel incision has advantages of both scleral tunnel incision and clear corneal tunnel incision. The postoperative therapeutic effects are satisfactory.

Reactions of first-row transition metal ions with propargyl alcohol in the gas phase

The gas-phase reactions with propargyl alcohol (PPA) of all the singly charged ions of the first-row transition metals, generated by laser ablation in an external ion source, were studied by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICRMS.). The reactivities of the metal ions change irregularly across the periodic table, and the reactivity of each ion is a function of its electronic configuration and corresponding metal-oxygen (M-O) bond energies. The 10 metal ions were classified into three categories according to their reactivities: Sc(+), Ti(+) and V(+) are the most reactive ions which react with PPA to give many kinds of oxygen-rich products due to stronger M-O bonds; Fe(+), Co(+) and Ni(+) are less reactive; Cr(+), Mn(+), Cu(+) and Zn(+) are the most unreactive ions, due to the half and completely occupied valence electronic configurations. The order of reactivity is Ti(+) > V(+) > Sc(+) >> Co(+) > Fe(+) approximately Ni(+) > Zn(+) > Cr(+) approximately Mn(+) approximately Cu(+).

Formation of binary alloy cluster ions from group-14 elements and cobalt and comparison with solid-state alloys

By using laser ablation on mixtures of transition metal cobalt and group-14 elements, binary alloy cluster anions were produced while no binary alloy cluster cations were detected, and the homocluster cations of group-14 elements appeared at very low abundance. The differences between clustering abilities of germanium, tin and lead with cobalt are described, and the chemical bonds in the binary alloy cluster anions appear to indicate a transition from covalent to metal bonds. The cluster anion [CoPb10](-) appears in very high abundance (magic number), and an endohedral structure is proposed for this cluster. The cluster anion [CoPb12](-), also representing a magic number, probably has an icosahedral structure. Compared with solid-state Co/Ge binary alloys, the compositions of most binary alloy cluster anions are germanium-rich, in which the covalent bonds are predominant.

[Effects of 1 alpha(OH)D3 on trabecular and cortical bone in ovariectomized rats]

OBJECTIVE

To study the pharmaceutical effects of 1 alpha(OH)D3 on trabecular and cortical bone in ovariectomized (OVX) rats.

METHODS

41 female Wistar rats of six months old were randomly divided into 5 groups: (1) Baseline control; (2) Sham control; (3) 6 weeks after OVX (OVXb); (4) 14 weeks after OVX (OVXe); (5) OVX + 0.1 microgram/(kg.d) 1 alpha(OH)D3 (O + VD), treatment started 6 weeks after OVX and lasted 8 weeks. Histomorphometry analysis of tibia, peripheral quantitative computed tomography (pQCT) scanning of femur, bone biomechanical test and serum and urinary biochemical parameters were determined.

RESULTS

The levels of bone turnover indexes increased in OVX rats, OVX also resulted in reducing of trabecular, bone mass and biomechanical properties. The ratio of urinary deoxypyridinoline crosslink/creatinine was decreased by 67.0% in O + VD group compared with OVXe group 67.0% [(43.50 +/- 11.20) nmol.L-1/mmol.L-1 vs(131.80 +/- 14.90) nmol.L-1/mmol.L-1, P < 0.01]. Percent trabecular area (Cn-BV/TV) was increased by 89.8% in O + VD group compared with OVXe group (11.03 +/- 0.73 vs 5.81 +/- 1.29, P < 0.05). Trabecular bone mineral content and density were increased by 77.3% and 91.3% compared with OVXe respectively (P < 0.05). Although cancellous maximal load and stiffness increased in O + VD group, but no statistical significance. 1 alpha(OH)D3 also enhanced polar moment of inertia (PMI) and maximal load of cortical bone in femur compared with OVXe (23.70 +/- 1.63 vs 18.23 +/- 1.41, P < 0.01 and 171.69 +/- 9.92 vs 147.58 +/- 11.29, P < 0.05 respectively).

CONCLUSION

1 alpha(OH)D3 inhibited the higher bone turnover induced by OVX, increased trabecular bone in proximal tibia and bone mass in distal femur. 1 alpha(OH)D3 also improved the mechanical properties of cortical bone in femur.

Cell culture of biopsied endometriomas after danazol/hormonal therapy: a study of growth features and fertility effects

The growth features of cells from endometriomas biopsied from patients who had been treated with Danazol or with hormones have not been studied in vitro. Danazol is a versatile drug and despite its recognised efficacy in controlling endometriosis, little is known about is cytotoxicity and mechanism of action. Culture of the biopsied endometriomas permitted qualitative cytotoxic assessments by way of comparison with cultured normal uterine endometrial cells treated in vitro with Danazol. The growth characteristics were studied in monolayer and collagen gel cultures. Cytopathology was characterised by light and electron microscopy. Since endometriosis is associated with infertility in women, data from in vitro fertilisation (IVF) were analysed with respect to treatment modalities as compared with cases suffering fallopian occlusion. Danazol reduced pregnancy chances. Two factors may be responsible: (a) altered follicle development resulting in poor oocyte quality (b) reduced nidation because of long-lasting endometrial cytotoxicity. The experimental findings reported here support the latter explanation. Consequently, Danazol therapy should be conditional; patients wishing to achieve pregnancy should preferably receive hormonal therapy.

[Review on research of plant nutrient use efficiency]

The concept of nutrient use efficiency is the central to the understanding of ecosystem function. We reviewed the concept of nutrient use efficiency and resorption, its expression and calculation, affecting factors and biochemical basis, we also analyzed the current problems in the studies of nutrient use efficiency, and pointed out the directions for future research work of this field.

[Effects of alfacalcidol on osteoporosis in ovariectomized rats]

OBJECTIVE

To investigate the effects of alfacalcidol on osteoporosis in rats induced by ovariectomy (OVX).

METHODS

Fifty-three virgin female Wistar rats of six months old were divided into 6 groups: (1) rats in baseline group (base) were sacrificed what 6 months before OVX, and those in the other 5 groups were either bilaterally OVX or sham-operated (sham) as follows: (2) Sham; (3) OVX baseline (OVXb); (4) OVX end (OVXe); (5) OVX + 17beta-estradiol 20 microgram/kg.(-1) SC. (O + E); and (6) OVX + alfacalcidol 0.1 microgram/kg.(-1) oral (O + VD). Rats in OVXb group were sacrificed 6 weeks after OVX and the others were sacrificed 14 weeks after surgery. Alfacalcidol (TEVA, Israel) was fed orally at 6 weeks after OVX and lasted for 8 weeks. Urine and serum samples were collected before sacrifice to determine the bone turnover markers. The right tibia was processed undecalcified for histomorphometric analysis, and the right femur was prepared for pQCT scanning and bone biomechanical measurement with indentation test.

RESULTS

Treatment of OVX rats with alfacalcidol (O + VD) increased tibial cancellous bone volume in histomorphometric analysis (12.0% +/- 1.1% vs 5.8% +/- 1.3%, P < 0.01). pQCT scanning showed that trabecular BMC and BMD were sharply elevated in O + VD group compared with OVXe group, increased 109.2% and 133.1% respectively (P < 0.01). In consistency with these changes in mechanical competency of cancellous bone in distal femur, maximal load was enhanced in O + VD group compared with OVXe group (21.3% +/- 4.0% N vs 7.9% +/- 1.9% N, P < 0.05). All these changes in O + VD group were similar to those in 17beta-estradiol treatment group (O + E). Serum calcium concentration increased in O + VD group. Histomorphometric and biochemical indices of bone resorption reduced in O + VD group.

CONCLUSION

Alfacalcidol effectively prevent bone loss in OVX rats and restore partly the trabecula, with evidenced increasing density, contents as well as maximal loads of cancellous bone, and reduce bone resorption.

[Tissue engineering of skin]

OBJECTIVE

To review the recent progresses on tissue engineering of skin.

METHODS

Recent original articles about tissue engineering of skin were extensively reviewed, which focused on the progresses and major problems concerning the epidermal substitutes, dermal substitutes, cultured-epidermal composite skin graft.

RESULTS

Most investigators had come to conclusion that the optimal skin substitute should provide for immediate reconstruction of both the lost epidermis and dermis. The research was mainly focused on how to transplant epidermal cells immediately, preserve their activity and function, and develop the extracellular matrix which could effectively accelerate the function of transplanted cells, induce vascular growth from the wound bed, could be biodegradable, no toxicity and no danger of carrying pathogen.

CONCLUSION

The major research trends of tissue engineering of skin should be focused on the study of immediate transplantation of epidermal cells, accelerate wound healing and developing extracellular matrix of dermis.

[Beta-diversity of Stipa communities in Inner Mongolia Plateau]

The beta-diversity characteristics of four Stipa communities (S. baicalensis, S. grandis, S. krylovii and S. klemenzii) were studied using comparable plots methods. As a measurement of species turnover within communities, Whittacker's index(beta ws) was size-dependent, and reduced gradually with the increasing quadrat size. Under the same scale, beta ws indices of the communities were similar. Cody's index (beta c) was also affected by sampling size. beta c increased initially as quadrat size enlarged, then stabilized over the size of 0.5 m2 for S. baicalensis and S. grandis communities, and 2 m2 for S. krylovii and S. klemenzii communities. S. baicalensis community had the highest Cody index, while S. klemenzii community had the lowest one. In most cases, the within-community distance interval had a relatively high effect on Cody index; From S. baicalensis to S. klemenzii community, the functional group diversities of forbs, perennial bunch and rhizome grasses decreased greatly, the diversity of intermediate xerads reduced significantly, and the diversity of xerads increased firstly, and then declined for S. klemenzii community. The changes in species composition of four Stipa communities could give a reflection to the degrees of community replacement along ecological gradients, and Cody indices between the communities reduced gradually. The Morisita-Horn similarity coefficient between S. baicalensis and S. grandis community was significantly higher (0.72) than those between S. grandis and S. krylovii communities (0.55), and between S. krylovii and S. klemenzii communities(0.42).

[Study on risk factors of breast cancer among urban women in China]

OBJECTIVE

Breast cancer is the most common malignant neoplasm in women all over the world. It is necessary to establish monitoring methods and to identify risk factors.

METHODS

Six cities including Beijing, Shanghai, Tianjin, Chongqing, Wuhan and Guangzhou were chosen as the sample areas. 2 100 cases with 1:1 matched controls were interviewed with a uniformed questionnaire. Conditional logistic regression and cluster analysis were used for multivariate analysis.

RESULTS

The common risk factors for the combined data of the six cities were high educational level (OR: 1.17), high body mass index (OR: 1.51), high intake of milk products (OR: 1.49), high intake of eggs (OR: 1.14), psychological depression (OR: 2.78), history of benign breast diseases (OR: 2.24), old age at marriage (OR: 1.42), dysmenorrhea (OR: 1.22), short duration of lactation (OR: 1.17). Among these factors, different cities had different ORs, as high educational level (OR: 1.20 - 1.61), high body mass index (OR: 1.40 - 22.36), high intake of milk products (OR: 1.64 - 3.39), depression (OR: 1.60 - 10.50), history of benign breast diseases (OR: 1.73 - 19.44). Some statistically significant correlations existed in different cities such as early age at menarche, old age at marriage, long menstrual periods, high intake of meat, eggs, sea food and passive smoking were risk factors. Some risk factors varied between premenopausal and postmenopausal women. Beijing, Wuhan and Chongqing were clustered as the same group in cluster analysis, so did Shanghai and Tianjin, but Guangzhou could not be grouped with other cities.

CONCLUSION

Some common risk factors for breast cancer did exist in the six cities, but there were varieties in different areas which showed different places would have their own characteristics. Thus, careful study of risk factors, especially in the selection of variables and data analysis need to be carried on.

[Changes of the responses of arterioles to noradrenaline, acetylcholine and nitroglycerin after limb ischemia-reperfusion]

OBJECTIVE

To explore the mechanism of microvascular spasm after limb ischemia-reperfusion.

METHODS

The rabbit hindlimb normothermic tourniquet ischemia model was employed. The tendon on the dorsum of the foot was exposed for observation of microvessels. The responses of arterioles on tendon surface to topical application of 10(-6) mol/L noradrenaline (NE) (a vasoconstrictor), 10(-6) mol/l acetylcholine(Ach) (an endothelium-dependent vasodilator) and 10(-4) mol/L nitroglycerin(NTG) (an endothelium-independent vasodilator) were observed at the period of ischemia and following 30 minutes of reperfusion after 2 hours and 5 hours of ischemia by use of intravital microscopy.

RESULTS

No significant changes in the responses of arterioles to NE, Ach and NTG were noted following 30 minutes of reperfusion after 2 hours of ischemia compared with pre-ischemia. The constrictor responses of arterioles to NE were still not significantly altered following 30 minutes of reperfusion after 5 hours of ischemia, however, the dilation responses to Ach and NTG were significantly decreased (to Ach P < 0.01; to NTG, P < 0.05).

CONCLUSION

Reperfusion after 5 hours of ischemia significantly impairs both the endothelium-dependent and endothelium-independent vasodilation, meanwhile preserves constrictor responses to NE, these may contribute to the genesis of the vasospasm in ischemia reperfusion.

[Bone marrow transplantation for beta-thalassemia major]

OBJECTIVE

To examine the feasibility of bone marrow hematopoietic stem cell transplantation for thalassemia major.

METHODS

Bone marrow transplantation was performed on a 4-year-old patient with beta-thalassemia major, whose gene mutation was CD41-42/654. The donor was his brother. In the 850ml bone marrow, the nucleated cells were 5.6x10(8)/kg, CD(+)(34) cells 7.8 x 10(6)/kg, and colony-forming-unit-granulocyte-macrophages(CFU-GM) 5.7x10(5)/kg. HLA was one site mismatched, while RBC type matched. Pre-transplant conditions included Busulfan 16mg/kg, cyclophosphamide 200mg/kg and lymphoglobuline 88mg/kg. Cyclosporine and methotrexate were used for prevention of graft-versus-host disease(GVHD).

RESULTS

After transplantation, the patient had grade II acute GVHD and cytomegalovirus(CMV) interstitial pneumonia; he was cured. White blood cells(WBC) and neutrophil granulocytes recovered to 1.1 x 10(9)/L and 0.4 x10(9)/L respectively on day 14 post transplantation. WBC was 4.5 x 10(9)/L on day 18, and descended for a time during treating interstitial pneumonia with Ganciclovir. Platelet(Plt) exceeded 50 x 10(9)/L on day 86 and recovered to normal 5 mothers and a half post transplantation. Hb reached 106g/L on day 128. The patient received the last blood transfusion on day 103. Before transplantation, the patient had to receive 200ml blood infusion per month for maintaining Hb 60-90g/L; after transplantation, his Hb kept up >110g/L for 6 months without blood transfusion. The gene type had changed to donor's CD41-42/N heterozygen.

CONCLUSION

This is the first report on successful transplantation of bone marrow stem cell for thalassemia major in China, suggesting a new way to treat the disease and to expand the use of BMT. For treatment of CMV interstitial pneumonia post-transplantation, Ganciclovir should be dose enough and be used for at least 2 months.

The ets protein PEA3 suppresses HER-2/neu overexpression and inhibits tumorigenesis

Because HER-2/neu overexpression is important in cancer development, we looked for a method of suppressing the cell transformation mediated by HER-2/neu overexpression. We have identified that the DNA-binding protein PEA3, which is encoded by a previously isolated gene of the ets family, specifically targeted a DNA sequence on the HER-2/neu promoter and downregulated the promoter activity. Expression of PEA3 resulted in preferential inhibition of cell growth and tumor development of HER-2/neu-overexpressing cancer cells. This is a new approach to targeting HER-2/neu overexpression and also provides a rationale to the design for repressors of diseases caused by overexpression of pathogenic genes.

[Cytologic and histopathologic examinations of fine-needle aspirates of pancreatic mass]

OBJECTIVE

To evaluate the usefulness in diagnosis of pancreatic mass by histopathologic and cytologic examinations of fine-needle aspirates obtained under ultrasonic guidance.

METHODS

In 83 patients with pancreatic mass, percutaneous fine-needle aspiration was performed under ultrasound guidance. The fluid aspirates were examined cytologically and tissue fragments examined histopathologically. The findings were compared.

RESULTS

The rate of accuracy, sensitivity, and specificity of cytologic examination was 98.8%, 98.3% and 100% respectively, and that of histopathologic diagnosis was 95.1%, 93.2% and 100%, respectively. There was no false positive.

CONCLUSION

Both histopathologic and cytologic examinations of fine-needle aspirates of pancreatic mass are sensitive and accurate enough for the diagnosis of pancreatic diseases. They can be used with complementarity.

[Bone mineral analysis of whole body in 292 normal subjects assessed by dual X-ray absorptiometry]

OBJECTIVE

To understand whole body bone mineral changes in normal subjects.

METHODS

Bone mineral was measured by dual X-ray absorptiometry (DXA) in 292 normal subjects aged 10-79, including 152 females and 140 males. They were divided into age-groups by decade.

RESULTS

In males, peak value ages of total bone mineral content(TBMC), total bone mineral density(TBMD), anteroposterior spine BMD(L2-4 BMD) were in the 30-39, 20-39, 20-29 age-groups respectively. In females, they were all in the 30-39 age-group. Peak values of TBMC, TBMD, L2-4BMD were higher in males than those in females. Loss of bone mineral for females was more pronounced than that for males. There was a tendency of increased BMD among the 70-79 age-group for males. Loss of L2-4 BMD was more pronounced than TBMD.

CONCLUSIONS

This study provides the normal bone mineral data of whole body for males and females, and the characteristic of changes.

[Orbital fat preservation and orbicularis muscle flap suspension for lower eyelid pouches]

OBJECTIVE

This is to introduce the experience in the treatment of lower eyelid pouches by orbital fat preservation and orbicularis oculi muscle flap suspension techniques.

METHODS

From Sept. 1996 to May 1997, thirty patients with lower eyelid pouches were treated using Hamra's procedure. During the operation, the arcus marginalis was incised. The orbital fat was released and advanced beyond the infraorbital rim and sutured. A lateral-based orbicularis oculi muscle flap was created, and its pedicle was repositioned to the periosteum of the upper lateral orbital rim in a superiomedial direction.

RESULTS

A total of 26 patients were available for postoperative follow-up for 3 to 8 months (mean 5.6 months). Of them one patient developed unilateral lower eyelid ectropion due to flabby reposition of the orbicularis oculi muscle flap. The rest obtained excellent cosmetic results without complications.

CONCLUSION

This new method has following advantages: 1. The lower eyelid pouches and the infraorbital rim show that may be corrected simultaneously: 2. Sunken eyelids and scleral show that may follow fat removal in conventional lower blepharoplasty can be effectively avoided. 3. "Cheek lift" and a youthful eyelid-cheek complex contour can be obtained.

[The study of new bio-membrane-bred epidermal cell grafts]

OBJECTIVE

The human epidermal cells were bred on a kind of bio-membrane, the bio-brane, in engineering a kind of new epidermal substitute, the bio-membrane bred cell graft.

METHODS

Fresh and frozen grafts of biomembrane bred epidermal cells were transplanted into the full-thickness wounds of nude mice and those received simple Bio-brane were served as control. The wounds of the two groups were observed daily and biopsy was taken on the 3, 5, 7, 10, 21 and 35 days respectively.

RESULTS

Epidermal cells could be cultured in vitro on the bio-membrane reaching the sub-saturated state of 60 to 70 percents. The bio-membrane after being grafted the epidermal cells continued to proliferate and differentiate to form a layer of new epidermis. There was no difference between the fresh and the frozen bio-membranes.

CONCLUSION

Bio-membrane bred with epidermal cells could be a kind of ideal epidermal substitute.

[Evaluation of the risk of vertebral fracture predictable with quantitative tibial ultrasound velocity test in postmenopausal women]

OBJECTIVE

To investigate predicting value of increased risk of vertebral fracture associated with reduction of tibial ultrasound velocity (SOS) test in postmenopausal women.

METHODS

193 menopausal women aged(54.4 +/- 7.3) years were included in our study. Post menopausal period of these subjects were (16.0 +/- 7.8) years. These participants received tibial ultrasound speed (SOS) test, DEXA for lumbar 2-4, femoral neck wards triangle and trochant, as well as SPA for 1/3 and 1/10 of distal forearm. Vertebral fracture was determined by radiograph of lateral lumbar and thoracic spine.

RESULTS

54 subjects were found at least one vertebral deformation, and no vertebral deformation was found in other 139 subjects. Tibial SOS was significantly lower in subjects with than without vertebral fracture [(3,651.9 +/- 188.3) vs (3,731.3 +/- 140.8), P < 0.01], The similar results were also found in BMD. The analysis of logistic regression showed: odds ratio (OR) of SOS to vertebral fracture was 1.86(P < 0.01) when 1 standard deviation of SOS changed. It was lower than OR of BMD by DEXA(2.25-3.28, all P < 0.001), and similar with OR of BMD by SPA (1.50-1.96).

CONCLUSIONS

Low SOS was associated with presence of vertebral fracture in postmenopausal women. SOS could predict the risk of vertebral fracture, 86% of the risk of vertebral fracture increased when 1 standard deviation of SOS reduced.

Normal changes in spinal bone mineral density in a Chinese population: assessment by quantitative computed tomography and dual-energy X-ray absorptiometry

This study was designed to determine age- and gender-based normative values for spinal bone mineral density (BMD) in a Chinese population. In addition, we compared our data with those of other countries and populations. Four hundred and forty-three healthy Chinese subjects, aged 10-79 years (189 males, mean age 46.9 years; 254 females, mean age 45.7 years) were recruited for BMD assessment. BMD was measured by quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA), including posteroanterior DXA (PA-DXA), lateral DXA (L-DXA) and midlateral DXA (mL-DXA). For both genders, BMD values peaked in the 10-19 year age group when measured by QCT, and in the 30-39 year age group when measured by PA-DXA. BMD values decreased with age after reaching peak bone density in males and females for all measurements, except for PA-DXA in males. Male BMD values by DXA tended to increase beginning with the 60-69 age group through the 70-79 age group whether by PA-DXA, or L-DXA and mL-DXA. However, male QCT data showed stable BMD values among these two older groups. Comparative results showed female QCT data were higher in the 20-39 age group and lower after the 40-49 age group compared with American females. The peak BMD value by PA-DXA in Chinese females was reached in the same age group as American and European females and was similar in magnitude (p > 0.05). However, the peak BMD value for Chinese females was reached earlier and was significantly higher than that observed in Japanese females (p < 0.001). We conclude that the age group in which the peak BMD values are reached is different depending on the technique used, as is the calculated age-related rate of bone loss. It can be speculated that such differences reflect different timing for bone maturation in cancellous and cortical bone.

LDL oxidation by activated monocytes: characterization of the oxidized LDL and requirement for transition metal ions

Monocytes can be activated by incubation with opsonized zymosan (Zop), and under these conditions can oxidize low density lipoprotein (LDL). We have characterized the biochemical changes in the lipoprotein after this oxidation. We found that monocyte-oxidized LDL has increased mobility on agarose gels, increased absorbance at 234 nm, increased content of lysophosphatidylcholine, and fluorescence at 430 nm when excited at 350 nm. All these features were somewhat less pronounced in monocyte-oxidized LDL than in LDL oxidized by 5 micrometer CuSO4. Under appropriate conditions, Zop-stimulated monocytes oxidized LDL to a form recognized by macrophage scavenger receptors. Monocytes stimulated by Zop produced superoxide and also oxidized LDL, whereas monocytes stimulated by phorbol ester produced slightly more superoxide but did not oxidize LDL. We found that the chelators EDTA and diethylenetriaminepentaacetic acid inhibited LDL oxidation by Zop-stimulated monocytes, implying a requirement for transition metal ions. We found that Zop contained approximately 5 nmol iron per mg, probably as Fe3+. Zop stripped of its iron supported superoxide production by monocytes, but did not support LDL oxidation. Furthermore, Fe2+ appeared in the medium when monocytes were incubated with Zop, but not with iron-stripped Zop. Taken together, these results imply that monocytes stimulated by Zop are able to oxidize LDL only because of contaminating iron in the commercial zymosan preparations. and requirement for transition metal ions.

Safety study and characterization of E1A-liposome complex gene-delivery protocol in an ovarian cancer model

A phase I clinical trial of E1A-liposome complex is currently ongoing in patients with HER-2/neu-overexpressing breast or ovarian cancers. To optimize the E1A-liposome complex for a further stage of clinical trial, several aspects of the current protocol have been examined in an animal model. In the orthotopic ovarian cancer model, different doses of lipid in the the E1A-liposome complex, which is currently used in clinical trials, were tested for the in vivo gene-transfer efficacy and tumor-suppression function. A lowered lipid dose--1/13 of the previous amount--produced gene expression level and E1A tumor-suppression efficacy similar to that of the original protocol. Mini-E1A, an E1A construct without its immortalization domain and yet capable of repressing HER-2/neu, was proved to be as potent as E1A in suppressing tumor development in vivo. These changes in the E1A-liposome complex will significantly reduce any potential adverse effects caused by lipid vector and E1A DNA. To examine further whether residual E1A DNA may still exist in normal organs after the E1A-liposome treatment, PCR was used to detect E1A DNA in mice that survived for 1 1/2 years after the last treatment. E1A DNA was detected only in the lungs and kidneys, but not in livers, hearts, spleens, brains, uterus or the ovaries. Furthermore, resistance of the E1A DNA extracted from tissues to the digestion of Dpnl restriction enzyme, which can cleave the methylated E1A plasmid DNA generated by methylation-competent bacteria, suggested integration of E1A DNA into the chromosome of the lungs and kidneys. Experimental results presented here provide important information for safety concerns and for the design of future phase II and phase III trials.

DNA ligase gene disruptions can depress viral growth and replication in poxvirus-infected cells

Poxvirus-encoded DNA ligases are assumed to play a role in viral DNA replication; however mutational inactivation of vaccinia ligase has not been reported to affect viral growth rates in culture. This communication re-examines this surprising aspect of poxviral biology using both Shope fibroma virus (SFV) and vaccinia virus. SFV and vaccinia ligase deficiencies create essentially identical phenotypes. In particular, ligase-deficient SFV strains are mildly UV sensitive and etoposide resistant, phenotypes previously shown to characterize ligase-deficient vaccinia strains. Moreover, we find that ligase mutations can inhibit the growth of both SFV and vaccinia virus in vitro. The poor growth observed in the absence of a viral ligase is correlated with a two- to tenfold reduction in viral and extragenomic DNA synthesis. This phenotype is host dependent. No differences in viral growth or DNA yield were seen when vaccinia strains were cultured on rabbit (SIRC) cells, but ligase deficiencies reduced growth and DNA yields when vaccinia was plated on BSC-40 cells or SFV on SIRC cells. Despite these replicative defects, mutational inactivation of SFV ligase produced no detectable increase in the number of viral DNA breaks and had no effect on virus-catalyzed extragenomic DNA recombination or UV repair. We conclude that poxviral ligases do play a role in viral DNA replication, but the replicative defect is obscured in some cell lines.

[Preserving remnant liver function after major hepatic vein occlusion]

OBJECTIVE

To observe the pathological changes of the remained hepatic lobe after major hepatic vein (MHV) occlusion.

METHOD

Seventy-eight rats were randomly divided into the control group, the ligation group of segmental hepatic vein, the stricture group of left MHV, and the ligation group of left MHV. The pathology, hepatic microcirculation and hemodynamic changes of the involved hepatic lobe of MHV occlusion were dynamically determined.

RESULT

Necrosis occurred in the hepatocytes at the first postoperative day in the ligation group of MHV. Extensive collaterals between the hepatic veins and the portal veins appeared in the periphery of involved liver lobe in the stricture group of MHV. The levels of endotoxin and TXB(2)/6-Keto-PGF1alpha in the blood of portal vein obviously increased in the ligation group of MHV and also increased in the stricture group of MHV. The levels of endotoxin and TXB(2)/6-Keto-PGF1alpha in the blood of portal vein in the ligation and stricture group of MHV were apparently higher than those in the ligation group of segmental hepatic vein and in the control group.

CONCLUSION

The involved liver tissue can not tolerate complete MHV occlusion. The hepatic tissue lacking of MHV drain not only loss its function, but also cause endotoxemia and disorder of hepatic microcirculation. The involved hepatic lobe after the MHV ligation should have been resected at the same time.