Exosomes derived from induced cardiopulmonary progenitor cells alleviate acute lung injury in mice

Cardiopulmonary progenitor cells (CPPs) constitute a minor subpopulation of cells that are commonly associated with heart and lung morphogenesis during embryonic development but completely subside after birth. This fact offers the possibility for the treatment of pulmonary heart disease (PHD), in which the lung and heart are both damaged. A reliable source of CPPs is urgently needed. In this study, we reprogrammed human cardiac fibroblasts (HCFs) into CPP-like cells (or induced CPPs, iCPPs) and evaluated the therapeutic potential of iCPP-derived exosomes for acute lung injury (ALI). iCPPs were created in passage 3 primary HCFs by overexpressing GLI1, WNT2, ISL1 and TBX5 (GWIT). Exosomes were isolated from the culture medium of passage 6-8 GWIT-iCPPs. A mouse ALI model was established by intratracheal instillation of LPS. Four hours after LPS instillation, ALI mice were treated with GWIT-iCPP-derived exosomes (5 × 109, 5 × 1010 particles/mL) via intratracheal instillation. We showed that GWIT-iCPPs could differentiate into cell lineages, such as cardiomyocyte-like cells, endothelial cells, smooth muscle cells and alveolar epithelial cells, in vitro. Transcription analysis revealed that GWIT-iCPPs have potential for heart and lung development. Intratracheal instillation of iCPP-derived exosomes dose-dependently alleviated LPS-induced ALI in mice by attenuating lung inflammation, promoting endothelial function and restoring capillary endothelial cells and the epithelial cells barrier. This study provides a potential new method for the prevention and treatment of cardiopulmonary injury, especially lung injury, and provides a new cell model for drug screening.

Mechanism of gel immobilization driving efficient anammox in mainstream partial nitritation/anammox process: Structural characterization and multi-perspective microbial analysis

Here, the mechanism of encapsulated anammox bacteria (AnAOB) driving efficient nitrogen removal in the mainstream partial nitritation/anammox process is revealed. The results show that a high nitrogen removal rate (1.21±0.02 kgN·(m3·d)-1) was achieved due to the abundant micropore structure inside the anammox immobilized filler, ensuring good connectivity, and a stable aggregation capacity, reducing dependence on extracellular polymeric substances. AnAOB were uniformly distributed throughout all regions of the immobilized filler, and their abundance was higher than that of the control anammox granular sludge (AnGS). Conversely, cracks appeared on the surface of the AnGS, and hollows formed inside. The metagenome analysis revealed that the immobilized filler supported the coexistence of multiple AnAOB, and the appropriate niche enhanced coordination between the AnAOB and dominant companion microorganisms. In contrast, AnGS exhibited stronger NH4+-N and NO2--N loops, potentially reducing the total nitrogen removal efficiency. This study promotes the mainstream application of anammox.

LDLR is an entry receptor for Crimean-Congo hemorrhagic fever virus

Crimean-Congo hemorrhagic fever virus (CCHFV) is the most widespread tick-born zoonotic bunyavirus that causes severe hemorrhagic fever and death in humans. CCHFV enters the cell via clathrin-mediated endocytosis which is dependent on its surface glycoproteins. However, the cellular receptors that are required for CCHFV entry are unknown. Here we show that the low density lipoprotein receptor (LDLR) is an entry receptor for CCHFV. Genetic knockout of LDLR impairs viral infection in various CCHFV-susceptible human, monkey and mouse cells, which is restored upon reconstitution with ectopically-expressed LDLR. Mutagenesis studies indicate that the ligand binding domain (LBD) of LDLR is necessary for CCHFV infection. LDLR binds directly to CCHFV glycoprotein Gc with high affinity, which supports virus attachment and internalization into host cells. Consistently, a soluble sLDLR-Fc fusion protein or anti-LDLR blocking antibodies impair CCHFV infection into various susceptible cells. Furthermore, genetic knockout of LDLR or administration of an LDLR blocking antibody significantly reduces viral loads, pathological effects and death following CCHFV infection in mice. Our findings suggest that LDLR is an entry receptor for CCHFV and pharmacological targeting of LDLR may provide a strategy to prevent and treat Crimean-Congo hemorrhagic fever.

Direct Observation of Coherent Longitudinal and Shear Acoustic Phonons in TaAs Using Ultrafast X-Ray Diffraction

Using femtosecond time-resolved x-ray diffraction, we investigated optically excited coherent acoustic phonons in the Weyl semimetal TaAs. The low symmetry of the (112) surface probed in our experiment enables the simultaneous excitation of longitudinal and shear acoustic modes, whose dispersion closely matches our simulations. We observed an asymmetry in the spectral line shape of the longitudinal mode that is notably absent from the shear mode, suggesting a time-dependent frequency chirp that is likely driven by photoinduced carrier diffusion. We argue on the basis of symmetry that these acoustic deformations can transiently alter the electronic structure near the Weyl points and support this with model calculations. Our study underscores the benefit of using off-axis crystal orientations when optically exciting acoustic deformations in topological semimetals, allowing one to transiently change their crystal and electronic structures.

Photocurrent-driven transient symmetry breaking in the Weyl semimetal TaAs

Symmetry plays a central role in conventional and topological phases of matter, making the ability to optically drive symmetry changes a critical step in developing future technologies that rely on such control. Topological materials, like topological semimetals, are particularly sensitive to a breaking or restoring of time-reversal and crystalline symmetries, which affect both bulk and surface electronic states. While previous studies have focused on controlling symmetry via coupling to the crystal lattice, we demonstrate here an all-electronic mechanism based on photocurrent generation. Using second harmonic generation spectroscopy as a sensitive probe of symmetry changes, we observe an ultrafast breaking of time-reversal and spatial symmetries following femtosecond optical excitation in the prototypical type-I Weyl semimetal TaAs. Our results show that optically driven photocurrents can be tailored to explicitly break electronic symmetry in a generic fashion, opening up the possibility of driving phase transitions between symmetry-protected states on ultrafast timescales.

[The application of artificial intelligence on the classification of benign and malignant breast tumors based on dynamic enhanced MR images]

This retrospective analysis was conducted on clinical obtained DCE-MR images of 198 patients, age from 21 to 79 years(45.5±13.7). The CBAM-ResNet model was developed to perform the classification automatically at the image-level based on deep learning method using the pathological examination as the reference standard,then the classification result of each individual patient was obtained by ensemble learning. The proposed method can have an accuracy of 82.69% for correctly distinguishing between benign and malignant breast tumors at the slice-level based on CBAM-ResNet model and with a sensitivity of 85.67%.. After the voting mechanism is applied, the classification accuracy can reach up to 88.24% at the patient-level with a sensitivity of 87.50%. Our experimental results demonstrated the proposed approach have a high classification accuracy.

[Effect of cotton-moxibustion on chronic eczema and quality of life]

OBJECTIVE

To compare the therapeutic effect between cotton-moxibustion and compound flumetasone ointment, and observe the effect on quality of life in patients with chronic eczema.

METHODS

A total of 66 patients with chronic eczema were randomized into an observation group (33 cases, 2 cases dropped off) and a control group (33 cases, 2 cases dropped off). In the observation group, cotton-moxibustion was adopted on target skin lesion, once a day, 3 cones a time. In the control group, external application of compound flumetasone ointment was given twice a day. The treatment for 3 weeks was required in the both groups. Before treatment and 1,2,3 weeks into treatment, scores of visual analogue scale (VAS), eczema area and severity index (EASI) and dermatology life quality index (DLQI) were observed, and the recurrence rate was evaluated in the follow-up one month after treatment.

RESULTS

Compared before treatment, the VAS scores of 1,2,3 weeks into treatment, the EASI and DLQI scores of 2,3 weeks into treatment were decreased in the both groups (P<0.05), and those in the observation group were lower than the control group (P<0.05). The follow-up recurrence rate in the observation group were lower than the control group (P<0.05).

CONCLUSION

Cotton-moxibustion can effectively improve the pruritus symptom, skin lesion and quality of life in the patients with chronic eczema, the therapeutic effect is superior to the external application of compound flumetasone ointment.

Monoterpenoid indole alkaloids from the stems of Kopsia officinalis

Five new indole alkaloids, kopsiofficines H-L (1-5), along with fourteen known alkaloids (6-19) were isolated from the stems of Kopsia officinalis. Their structures were elucidated by extensive NMR, mass spectroscopic analyses and comparison to the reported data. All the isolated compounds were evaluated their anti-inflammatory activities by inhibiting IL-1β, PGE2 and TNF-α secretion in lipopolysaccharide (LPS)-activated RAW264.7 cells. Compounds 2, 3, 6, 7, 11, 12, 15, and 17 show significant anti-inflammatory activities. These results demonstrate pharmacodynamic substance basis of these folkloric claims.

Tracking Ultrafast Photocurrents in the Weyl Semimetal TaAs Using THz Emission Spectroscopy

We investigate polarization-dependent ultrafast photocurrents in the Weyl semimetal TaAs using terahertz (THz) emission spectroscopy. Our results reveal that highly directional, transient photocurrents are generated along the noncentrosymmetric c axis regardless of incident light polarization, while helicity-dependent photocurrents are excited within the ab plane. This is consistent with earlier static photocurrent experiments, and demonstrates on the basis of both the physical constraints imposed by symmetry and the temporal dynamics intrinsic to current generation and decay that optically induced photocurrents in TaAs are inherent to the underlying crystal symmetry of the transition metal monopnictide family of Weyl semimetals.

Temperature-Driven Topological Phase Transition and Intermediate Dirac Semimetal Phase in ZrTe_{5}

We present an infrared spectroscopy study of ZrTe_{5}, which confirms a recent theoretical proposal that this material exhibits a temperature-driven topological quantum phase transition from a weak to a strong topological insulating state with an intermediate Dirac semimetal state around T_{p}≃138  K. Our study details the temperature evolution of the energy gap in the bulk electronic structure. We found that the energy gap closes around T_{p}, where the optical response exhibits characteristic signatures of a Dirac semimetal state, i.e., a linear frequency-dependent optical conductivity extrapolating to the origin (after subtracting a weak Drude response). This finding allows us to reconcile previous diverging reports about the topological nature of ZrTe_{5} in terms of a variation of T_{p} that depends on the crystal growth condition.

Temperature-tunable Fano resonance induced by strong coupling between Weyl fermions and phonons in TaAs

Strong coupling between discrete phonon and continuous electron–hole pair excitations can induce a pronounced asymmetry in the phonon line shape, known as the Fano resonance. This effect has been observed in various systems. Here we reveal explicit evidence for strong coupling between an infrared-active phonon and electronic transitions near the Weyl points through the observation of a Fano resonance in the Weyl semimetal TaAs. The resulting asymmetry in the phonon line shape, conspicuous at low temperatures, diminishes continuously with increasing temperature. This behaviour originates from the suppression of electronic transitions near the Weyl points due to the decreasing occupation of electronic states below the Fermi level (E_F) with increasing temperature, as well as Pauli blocking caused by thermally excited electrons above E_F. Our findings not only elucidate the mechanism governing the tunable Fano resonance but also open a route for exploring exotic physical phenomena through phonon properties in Weyl semimetals.

The study of lattice vibrations coupled to electronic excitations may provide an avenue for exploring exotic physical phenomena. Here, Xu et al. observe a Fano resonance in the Weyl semimetal TaAs, revealing evidence for a strong coupling between phonons and Weyl fermions.

Superconductivity in HfTe5 across weak to strong topological insulator transition induced via pressures

Recently, theoretical studies show that layered HfTe₅ is at the boundary of weak & strong topological insulator (TI) and might crossover to a Dirac semimetal state by changing lattice parameters. The topological properties of 3D stacked HfTe₅ are expected hence to be sensitive to pressures tuning. Here, we report pressure induced phase evolution in both electronic & crystal structures for HfTe₅ with a culmination of pressure induced superconductivity. Our experiments indicated that the temperature for anomaly resistance peak (Tp) due to Lifshitz transition decreases first before climbs up to a maximum with pressure while the Tp minimum corresponds to the transition from a weak TI to strong TI. The HfTe₅ crystal becomes superconductive above ~5.5 GPa where the Tp reaches maximum. The highest superconducting transition temperature (Tc) around 5 K was achieved at 20 GPa. Crystal structure studies indicate that HfTe₅ transforms from a Cmcm phase across a monoclinic C2/m phase then to a P-1 phase with increasing pressure. Based on transport, structure studies a comprehensive phase diagram of HfTe₅ is constructed as function of pressure. The work provides valuable experimental insights into the evolution on how to proceed from a weak TI precursor across a strong TI to superconductors.

[Effect of inserted angle on the stability of loaded microscrews]

Objective: To evaluate the effect of different insertion angles on the osseointegration of loaded microscrews in beagle jaws. Methods: Forty-eight microscrews were inserted at four different angles (30°, 50°, 70° and 90°) into the interradicular zones between the mandibular first molar and third premolar in twelve beagles and the microscrews had been loaded with a force of 2 N immediately for 8 weeks. After microscrew-bone specimens fixed, the maximum output value (F_max) of pull-out test was recorded and the histomorphological changes of hard tissue were observed. The bone-implant contact (BIC%) was quantitatively analyzed and the osseointegration of microscrew-bone interface was comprehensively evaluated. Results: Both F_max and BIC% values of microscrews were influenced by the insertion angles. The maximum value of F_max was (385±23) N in the group with 50° angle, and the minimum value was (198±16) N in the group with 30° angle(P <0.05). The maximum value of BIC% was (59.1±6.0)% in the group with 70° angle, and the minimum value was (30.2±3.2)% in the group with 30° angle (P <0.05). Histomorphology observation revealed that in peri-screws region, the various degree of bone remodeling was found in different angle samples. Conclusions: The insertion angles (50°and 70°) were favorable to the stability of the microscrew.

Comparative Raman study of Weyl semimetals TaAs, NbAs, TaP and NbP

We report a comparative polarized Raman study of Weyl semimetals TaAs, NbAs, TaP and NbP. The evolution of the phonon frequencies with the sample composition allows us to determine experimentally which atoms are mainly involved for each vibration mode. Our results confirm previous first-principles calculations indicating that the A1, B1(2), E(2) and E(3) modes involve mainly the As(P) atoms, the B1(1) mode is mainly related to Ta(Nb) atoms, and the E(1) mode involves both kinds of atoms. By comparing the energy of the different modes, we establish that the B1(1), B1(2), E(2) and E(3) become harder with increasing chemical pressure. This behaviour differs from our observation on the A1 mode, which decreases in energy, in contrast to its behaviour under external pressure.

Polarization-independent plasmonic subtractive color filtering in ultrathin Ag nanodisks with high transmission

We demonstrate a TE/TM polarization-independent plasmonic subtractive color filtering scheme employing ultrathin two-dimensional Ag nanodisks. These TE/TM polarization-independent subtractive color filters exhibit small feature sizes (below 200 nm) and high transmission up to 70% in the visible spectral region, superior to previously reported plasmonic color filters. Simulated optical transmission spectra and colors are in good agreement with experimental results. The color-filtering behaviors strongly depend on thickness and period of nanodisks. Underlying mechanisms are also discussed in detail.

Observation of Fermi-Arc Spin Texture in TaAs

We have investigated the spin texture of surface Fermi arcs in the recently discovered Weyl semimetal TaAs using spin- and angle-resolved photoemission spectroscopy. The experimental results demonstrate that the Fermi arcs are spin polarized. The measured spin texture fulfills the requirement of mirror and time-reversal symmetries and is well reproduced by our first-principles calculations, which gives strong evidence for the topologically nontrivial Weyl semimetal state in TaAs. The consistency between the experimental and calculated results further confirms the distribution of chirality of the Weyl nodes determined by first-principles calculations.

Comparison of primary breast cancer size by mammography and sonography

PURPOSE

To compare tumor size by mammography and sonography and align with pathological results in primary breast cancer cases.

MATERIALS AND METHODS

We retrospectively reviewed 95 primary breast cancer patients who underwent mammography and sonography from January 2011 to June 2012. The largest tumor diameter was chosen as sizing reference for each imaging modality. The measurements of mammography and sonography were considered concordant if they were within the measurement of pathological results±0.5 cm. Pearson's correlation coefficient was calculated for imaging results.

RESULTS

The range of the maximum diameter was 0.6 cm-10.5 cm and mean value was 3.81±2.04 cm by pathological results, 0.7 cm-12.4 cm and 3.99±2.19 cm by mammography, and 0.9 cm-11.0 cm and 3.63±2.01 cm by sonography, respectively. Sonography (R: 0.754), underestimated tumor size, but had a better correlation with pathological tumor size compared to mammography (R: 0.676), which overestimated tumor size.

CONCLUSIONS

Sonography is superior to mammography in assessment of primary breast cancer.

DNA methylation status in tissues of sheep clones

Genomic imprinting and DNA methylation play an important role in mammalian development. Many cloned animals showed heterogeneous DNA methylation profiles. However, there are fewer reports in cloned lambs because of a lack of genomic imprinting information. In this study, we investigated DNA methylation patterns in CpG islands and differentially methylated regions of putative imprinted gene Peg10 and imprinted genes Dlk1, Igf2R and H19 in cloned lambs. Five organs from two cloned lambs died shortly after birth and two normal controls were investigated. We observed normal DNA methylation profiles in cloned lambs. The imprinted genes Dlk1, Igf2R and H19 in livers, kidneys, hearts, muscles and lungs of the two cloned lambs exhibited relatively normal DNA methylation, except for Peg10 showing some differences between controls and cloned lambs. Our results indicate that somatic cell nuclear transfer-produced sheep exhibited relatively normal DNA methylation pattern and experienced normal DNA methylation reprogramming at imprinted loci.

Protective effect of Jinhuangyidan Granules on liver injury in rats with severe acute pancreatitis

AIM: To investigate the protective effect of Jinhuangyidan Granules on liver injury in rats with severe acute pancreatitis (SAP) and to explore the possible mechanisms involved.

METHODS: Fifty-four male Sprague-Dawley (SD) rats were randomly divided into three groups: sham operation group, SAP group and Jinhuangyidan Granules group. Each group was further divided into three subgroups for testing at different time points after treatment (2, 6 and 12 h). SAP was induced by retrograde injection of 5% sodium taurocholate into the biliary pancreatic duct. Serum amylase (AMY), ALT, AST and the liver coefficient were measured. The levels of TNF-α, IL-6 and ET-1 were examined by ELISA, and the expression of NF-κB in the liver was evaluated by immunohistochemistry.

RESULTS: Compared to the sham operation group, the levels of AMY, ALT, AST, TNF-α, IL-6, ET-1 and NF-κB increased significantly in the SAP group. The liver coefficient also differed significantly between the sham operation group and SAP group at 6 and 12 h (both P < 0.05). Compared to the SAP group at 6 and 12 h, the levels of AMY, ALT, AST, TNF-α, IL-6, ET-1 and NF-κB decreased significantly in the Jinhuangyidan Granules group (all P < 0.05). At 6 h, the expression of liver NF-κB was significantly higher in the SAP group than in the sham operation group at 6 and 12 h (6 h: 49.89 ± 3.53 vs 5.32 ± 0.24; 12 h: 54.73 ± 1.68 vs 6.38 ± 0.24, both P < 0.05), but was significantly lower in the Jinhuangyidan Granules group than in the SAP group (6 h: 19.18 ± 1.51 vs 49.89 ± 3.53; 31.15 ± 2.25 vs 54.73 ± 1.68, both P < 0.05). Compared to the SAP group, the levels of edema and inflammatory mediators ameliorated significantly in the Jinhuangyidan Granules group.

CONCLUSION: Jinhuangyidan Granules ameliorates liver injury and improve microcirculation in SAP rats possibly by inhibiting NF-κB activity and down-regulating inflammatory mediators.

[Effects of gonadotropin on the expression of growth differentiation factor 9 and 9B in mouse ovary]

OBJECTIVES

To study the effects of gonadotropin on the expression of growth differentiation factor-9 (GDF-9) and -9B (GDF-9B) in mouse ovary.

METHODS

We chose follicles of mature mice cultured in vitro and mature BALB/c mice as our animal models. (1) In vivo experiment. Twenty mice were divided into two groups (groups A and B) randomly with ten mice in each group. Each mouse was injected with 10 IU pregnant mare's serum gonadotropin in group A and saline of the same volume was given to the other group. Twenty-four hours later we obtained ovarian tissue and immunohistochemistry and in situ hybridization were performed to detect the expression of GDF-9 and GDF-9B. (2) In vitro experiment. Fifty-eight separated follicles were divided into two groups (groups C and D) randomly and cultured in vitro. Thirty-two follicles in group C were cultured in medium with follicular stimulating hormone (FSH) for 72 hours while 26 were cultured without FSH. Immunohistochemistry was performed to detect the expression of GDF-9 in both groups.

RESULTS

We abserved 370 follicles by immunohistochemistry. The weak positive (+ or ++) rate was 22.0% and 46.2% while the strong positive (+++ or ++++) rate was 22.6% and 9.1% in 186 follicles of group A. The weak positive (+ or ++) rate in group B was 42.4% and 42.9% while the strong positive (+++ or ++++) rate was 14.1% and 0.5%. The expression of GDF-9 was higher in group A than that of group B. The weak positive rate, positive rate and strong positive rate in group C was 28.1%, 53.1% and 18.8% while that in group D was 61.5%, 30.8% and 7.7%, respectively. The expression of GDF-9 was higher in group C than that of group D. We observed 362 follicles by in situ hybridization. The weak positive (+ or ++) rate was 31.5% and 46.2% while the strong positive (+++ or ++++) rate was 21.2% and 1.1% in 184 follicles of group A. The weak positive (+ or ++) rate in group B was 39.9% and 41.6% while the strong positive (+++ or ++++) rate was 15.7% and 2.8%. There were no differences in the expression of GDF-9B between groups A and B.

CONCLUSION

Gonadotropin increases the expression of GDF-9 in vivo while FSH increases GDF-9 in vitro. Gonadotropin has no effects on the expression of GDF-9B.

Effects of sucrose concentration on the developmental potential of human frozen–thawed oocytes at different stages of maturity

BACKGROUND

Success of human oocyte cryopreservation depends on multiple cryobiological factors that could influence the developmental potential of the oocytes. The objective of this study was to examine the effects of different sucrose concentrations on the developmental potential of human frozen-thawed oocytes at different maturity stages.

METHODS

A total of 355 oocytes collected from small follicles were randomly divided into three groups and two groups (B and C) were cryopreserved using slow-freezing method. Group A included 131 oocytes at different maturity stages without freezing. Another 119 oocytes in Group B were cryopreserved with 0.1 M sucrose and 105 oocytes in Group C with 0.2 M sucrose concentration.

RESULTS

The post-thaw survival rate of the oocytes and the cleavage rate in Group C were significantly higher than that of Group B (P<0.05). For immature metaphase I (MI) stage oocytes, a significant difference was found in the maturation rate between Group C and Group B (P<0.05). The maturation rate for the GV oocytes in Groups A and C was significantly higher than Group B (P<0.01).

CONCLUSIONS

The results suggested that sucrose concentration of 0.2 M in the cryoprotectant solution is more suitable for human oocyte cryopreservation.

[Clinical analysis of multiple pregnancy reduction]

OBJECTIVE

To analyse the effect of the reduction of multiple pregnancy through transvaginal ultrasonic monitoring on the pregnancy outcome.

METHODS

Eighty-four cases were divided into two groups according to whether they had vaginal hemorrhage before operation. And the pregnancy outcomes were analyzed.

RESULTS

The abortion rate and preterm birth rate of the vaginal hemorrhage group were higher, and the difference was statistically significant.

CONCLUSIONS

The reduction of multiple pregnancy through transvaginal ultrasonic monitoring is a safe operative method. But it is only a remedial treatment for multiple pregnancy, and how to prevent multiple pregnancy is of more practical value.

Effects of lead on 4-aminobiphenyl pharmacokinetics in liver, kidney, spleen, testes, heart, lung and hemoglobin adduct for rat model

Lead affects almost every system in the body and 4-aminobiphenyl increases the incidence of bladder cancer among human exposed to aromatic amines, but little attention has been paid to the effects of lead (heavy metals) on the distribution and metabolic kinetics of 4-ABP (organic pollutants) in the organisms of the terrestrial ecosystems. In this study, male S.D. rats as model animals drinking tap water with and without lead with i.p. injection of 4-aminophenyl were used to study 4-aminobiphenyl pharmacokinetics with statistical analysis in three types of information systems: (1) hemoglobin adduct in the blood; (2) distribution concentrations in liver, kidney, spleen, testes, heart and lung; (3) relative weights of the six organs. Kinetic equations of 4-aminobiphenyl-hemoglobin adduct for two groups of rats drinking water with and without lead were all linear. Principal components were obtained based on three types of variants: (1) variants of distribution concentrations; (2) variants of relative weights; (3) variants of hemoglobin adduct, distribution concentrations and relative weights. Through a comparison of two groups of principal components, the result implied that lead changed 4-aminobiphenyl distribution kinetics in the six organs, had significant effects on the six organ relative weights, and had also significant effects on all thirteen variants as a whole. Correlation analysis of the principal components showed that lead could not significantly change the relation of hemoglobin adduct with time after dosing 4-aminobiphenyl. However, another result indicated that lead considerably improved the correlation between hemoglobin adduct and the thirteen variants as a whole. This implied that hemoglobin adduct could characterize all the thirteen variants as an index of 4-aminobiphenyl pharmacokinetics for the rats drinking water with lead, which conclusion was not suitable for the rats drinking water without lead. The research indicated that heavy metals existing in the organisms play an important role in the studies on pharmacotoxicology of organic pollutants. Frequently, various xenobiotics (heavy metals and organic pollutants) enter organisms simultaneously, therefore heavy metals should be considered comprehensively in the pharmacotoxicology of organic pollutants in animals in the terrestrial ecosystems theoretically and practically.

ABCA3 is a lamellar body membrane protein in human lung alveolar type II cells

The ABCA3 gene, of the ABCA subclass of ATP-binding cassette (ABC) transporters, is expressed exclusively in lung. We report here the cloning, molecular characterization, and distribution of human ABCA3 in the lung. Immunoblot analysis using the specific antibody reveals a 150-kDa protein in the crude membrane fraction of human lung. Immunohistochemical analyses of alveoli show that ABCA3 is expressed only in the type II cells expressing surfactant protein A. At the ultrastructural level, ABCA3 immunoreactivity was detected mostly at the limiting membrane of the lamellar bodies. Since members of the ABCA transporter family are known to be involved in transmembrane transport of endogenous lipids, our findings suggest that ABCA3 plays an important role in the formation of pulmonary surfactant in type II cells.

Synthesis, topoisomerase I inhibition and antitumor cytotoxicity of 2,2':6',2"-, 2,2':6',3"- and 2,2':6',4"-terpyridine derivatives

For the development of new anticancer agents, 2,2':6',2"-, 2,2':6',3"- and 2,2':6',4"-terpyridine derivatives were designed and evaluated for their topoisomerase I inhibitory activity and antitumor cytotoxicity. Structure-activity relationship studies indicated that 2,2':6',2"-terpyridine derivatives were highly cytotoxic toward several human tumor cell lines, whereas 2,2':6',3"- and 2,2':6',4"-terpyridine derivatives were potent topoisomerase I inhibitors.

Cloning, characterization and tissue distribution of the rat ATP-binding cassette (ABC) transporter ABC2/ABCA2

The ABC1 (ABCA) subfamily of the ATP-binding cassette (ABC) transporter superfamily has a structural feature that distinguishes it from other ABC transporters. Here we report the cloning, molecular characterization and tissue distribution of ABC2/ABCA2, which belongs to the ABC1 subfamily. Rat ABC2 is a protein of 2434 amino acids that has 44.5%, 40.0% and 40.8% identity with mouse ABC1/ABCA1, human ABC3/ABCA3 and human ABCR/ABCA4 respectively. Immunoblot analysis showed that proteins of 260 and 250 kDa were detected in COS-1 cells transfected with ABC2 having a haemagglutinin tag, while no band was detected in mock-transfected cells. After incubation with N-glycosidase F, the mobilities of the two proteins increased and a single band was detected, suggesting that ABC2 is a glycoprotein. Photoaffinity labelling with 8-azido-[alpha-(32)P]ATP confirmed that ATP binds to the ABC2 protein in the presence of Mg(2+). RNA blot analysis showed that ABC2 mRNA is most abundant in rat brain. Examination of brain by in situ hybridization determined that ABC2 is expressed at high levels in the white matter, indicating that it is expressed in the oligodendrocytes. ABC2, therefore, is a glycosylated ABC transporter protein, and may play an especially important role in the brain. In addition, the N-terminal 60-amino-acid sequence of the human ABC1, which was missing from previous reports, has been determined.

Design and synthesis of anticonvulsive agents as gamma-vinyl GABA-based potential dual acting prodrugs and their biological activities

For the development of new anticonvulsive agents, gamma-vinyl GABA (vigabatrin) and GABA mimetics derivatives were covalently coupled as potential dual acting prodrugs and evaluated for their anticonvulsive activities. Among the prepared compounds, 11 showed the most potent anticonvulsive activity, a shorter onset time and a broader spectrum compared to vigabatrin.

[Immunohistochemical study on myocardial acute ischemia reperfusion injury in rats with anti-FOS protein antibody]

To investigate law of FOS protein induced by myocardial ischemia reperfusion (MI/R) in acute period, a model in 20 anaethetized SD rats was established. Rats with normal and ischemia were used as control groups. Specimens were studied immunohistochemically with c-fos antibody. After ischemia 20 minutes, followed by 30 minutes reperfusion, the area of MI/R showed nuclei of myocytes positive staining in cryosection slides. In C2 group, the area showed nuclei of myocytes (37.76% +/- 9.66%) positive staining weakly. In C3 group, nuclei of cardiac myocytes(40.34% +/- 3.32%) was significantly positive. In C4 group it began to attenuate(35.36% +/- 4.81%). The myocardium in normal and ischemic control groups showed negative staining. No changes were seen with HE staining. Our data indicated that immunohistochemical method may reveal acute MI/R injury of ischemia 20 min and reperfusion 30 min with anti-FOS protein staining and there is problely a peak between 60-120 min after reperfusion. It is possible that the method be used to diagnose sudden cardiac death in forensic medicine.

Streptomyces thermogriseus, a new species of the genus Streptomyces from soil, lake and hot-spring

Many thermophilic actinomycetes were isolated from samples collected from a hot-spring, lake and soil in Yunnan, China. Chemical and molecular classification of four selected strains of thermophilic Streptomyces with an upper limited growth temperature of 65-68 degrees C and autolytic characteristics was carried out. A new species, Streptomyces thermogriseus sp. nov. is described. The type strain is Y-14046T (= CCTCC AA97014T).