The Triaging Effect of the Human Papillomavirus 16/18 E7 Oncoprotein Assay in HPV 16/18-Positive Patients for High-Grade Cervical Intraepithelial Neoplasia Screening: A Cross-Sectional Study

Objective: To investigate the triaging efficacy of the human papillomavirus (HPV) 16/18 E7 oncoprotein assay for high-grade cervical intraepithelial neoplasia (CIN2+) screening in HPV 16/18-positive patients in a tertiary hospital in China. Methods: We collected 476 cervical cell samples from women who tested positive for HPV 16/18 in the gynecological clinic of Peking Union Medical College Hospital between September 2018 and September 2022 and analyzed them by the HPV 16/18 E7 oncoprotein assay before colposcopy and biopsy. The study assessed the triaging efficacy of the HPV 16/18 E7 oncoprotein assay in HPV 16/18-positive patients by analyzing its performance against the gold standard of histologically confirmed CIN2+. Results: The positive rate of the HPV 16/18 E7 oncoprotein assay was 41.0% (114/278) in the negative for intraepithelial lesions and malignancy/CIN1 group and 80.3% (159/198) in the CIN2+ group. For triage of women with a positive HPV 16/18 test for CIN2+ detection, the HPV 16/18 E7 oncoprotein assay had a sensitivity, specificity, positive predictive value, and negative predictive value of 80.3%, 59.4%, 58.5%, and 80.9%, respectively. Furthermore, longitudinal follow-up of five patients showed a good correlation between the expression of the HPV 16/18 E7 oncoprotein and cervical lesion grades. Conclusions: As a triage method for HPV 16/18-positive patients, the HPV 16/18 E7 oncoprotein assay improves the specificity, reduces the colposcopy referral rate, and has the potential for long-term monitoring of high-grade CIN.

[A study of LEF1 protein expression in diagnosis and differential diagnosis of lymphoblastic lymphoma/acute lymphoblastic leukemia]

Objective: To evaluate the expression of LEF1 protein in lymphoblastic lymphoma/acute lymphoblastic leukemia (LBL/ALL) and small B-cell lymphomas, and its value in pathologic diagnosis and differential diagnosis of LBL/ALL. Methods: 53 cases of LBL/ALL were collected at shanghai Tongji Hospital from January 2012 to December 2019. The protein expression of LEF1 and TdT was detected by immunohistochemistry in 53 paraffin-embedded tissue samples of LBL/ALL. The specificity and sensitivity of LEF1 and TdT in the diagnosis of LBL/ALL were compared. The expression of LEF1 protein in 77 cases of small B-cell lymphomas including chronic lymphocytic leukemia/small lymphoid lymphoma (CLL/SLL), follicular lymphoma, mantle cell lymphoma, marginal zone lymphoma and Waldenstrom's macroglobulinemia/lymphoplasmacytic lymphoma was studied. The correlation between LEF1 expression and overall survival (OS) and progression-free survival (PFS) was performed by univariate analysis. Results: The expression of LEF1 in LBL/ALL was 100% (53/53), the median value was 90%; the expression of TdT was 84.9% (T-LBL/ALL 78.1%, B-LBL/ALL 95.2%), the median value was 80%; the expression rate and median value of LEF1 and TdT were significantly different (P=0.008 and 0.001 respectively). The expression of LEF1 in CLL/SLL was 14/18, the median value was 45%; LEF1 was not expressed in follicular lymphoma (0/16), mantle cell lymphoma (0/16), marginal zone lymphoma (0/19), and Waldenstrom's macroglobulinemia/lymphoplasmacytic lymphoma (0/8). LEF1 expression was significantly different between B-LBL/ALL and small B-cell lymphomas. The median follow-up time of LBL/ALL cases in this group was 16 months. There was no statistical difference between LEF1 expression and the OS and PFS in LBL/ALL patients. Conclusions: Immunohistochemical staining of LEF1 has high sensitivity and good specificity in the diagnosis of LBL/ALL, and its combination with TdT can improve the diagnostic rate of LBL/ALL.

Effect of experimental infections of various Tembusu virus strains isolated from geese, ducks and chickens on ducklings

In order to compare the pathogenicity of different Tembusu virus (TMUV) strains from geese, ducks and chickens, 56 5-day-old Cherry Valley ducklings which were divided into 7 groups and infected intramuscularly with 7´105 PFU/ml per duck of six challenge virus stocks. The clinical signs, weight gain, mortality, macroscopic and microscopic lesions, virus loads in sera of 1, 3, 5, 7, 11 and 14 dpi and serum antibody titers were examined. The results showed that these viruses could make the young ducks sick, but the clinical signs differed with the different species-original strains. All the experimental groups lose markedly in weight gain compared to the control, but there were no obvious distinctions in weight gains, as well as macroscopic and microscopic lesions of dead ducks between the infected groups. However, the groups of waterfowl-derived strains (from geese and ducks) showed more serious clinical signs and higher relative expressions of virus loads in sera than those from chicken-derived. The mortality of waterfowl groups was 37.5%, and the greatest mortality of chicken groups was 12.5%. The serum antibodies of the geese-species group JS804 appeared earlier and were higher in the titers than others. Taken toghter, the pathogenicity of waterfowl-derived TMUV was more serious than chicken-derived TMUV and JS804 could be chosen as one TMUV vaccine strain to protect from the infection.

Generation and characterization of a monoclonal antibody against duck Tembusu virus envelope protein

Duck Tembusu virus (DTMUV) is a newly emerging pathogenic flavivirus that has caused massive economic losses to the duck industry in China. Envelope (E) protein of DTMUV is an important structural protein, which is able to induce protective immune response in target animals and can be used as specific serological diagnosis tool. In this study, a novel monoclonal antibody, designated mAb 3E9, was generated against DTMUV E protein. It is positive in indirect ELISA against both His-E protein and the purified whole viral antigen. Also, this mAb showed positive reaction with DTMUV in Western blot and indirect immunofluorescence assay, and the isotype was IgG1. End-point neutralizing assay performed in BHK-21 cells revealed that the neutralization titer of 3E9 against DTMUV JS804 strain reached 1:50. Furthermore, functional studies revealed that 3E9 blocks infection of DTMUV at a step on viral attachment. The anti-E mAbs produced in the present work may be valuable in developing an antigen-capture ELISA test for antigen detection or a competitive ELISA test for antibody detection or therapeutic medicine for DTMUV in poultry.

Interface structure, precursor rheology and dielectric properties of BaTiO3/PVDF–hfp nanocomposite films prepared from colloidal perovskite nanoparticles

A novel and greatly simplified strategy was developed to fabricate high-permittivity dielectric nanocomposites. Interface structure, precursor rheology and dielectric properties of the 0–3 BaTiO₃/PVDF–hfp nanocomposite film were investigated.

Correction: Interface structure, precursor rheology and dielectric properties of BaTiO3/PVDF–hfp nanocomposite films prepared from colloidal perovskite nanoparticles

Correction for ‘Interface structure, precursor rheology and dielectric properties of BaTiO₃/PVDF–hfp nanocomposite films prepared from colloidal perovskite nanoparticles’ by Y. N. Hao et al., RSC Adv., 2017, 7, 32886–32892.

Graphite Carbon-Supported Mo2C Nanocomposites by a Single-Step Solid State Reaction for Electrochemical Oxygen Reduction

Novel graphite-molybdenum carbide nanocomposites (G-Mo₂C) are synthesized by a typical solid state reaction with melamine and MoO₃ as precursors under inert atmosphere. The characterization results indicate that G-Mo₂C composites are composed of high crystallization and purity of Mo₂C and few layers of graphite carbon. Mo₂C nanoparticles with sizes ranging from 5 to 50 nm are uniformly supported by surrounding graphite layers. It is believed that Mo atom resulting from the reduction of MoO₃ is beneficial to the immobilization of graphite carbon. Moreover, the electrocatalytic performances of G-Mo₂C for ORR in alkaline medium are investigated by cyclic voltammetry (CV), rotating disk electrode (RDE) and chronoamperometry test with 3M methanol. The results show that G-Mo₂C has a considerable catalytic activity and superior methanol tolerance performance for the oxygen reduction reaction (ORR) benefiting from the chemical interaction between the carbide nanoparticles and graphite carbon.

Novel VN/C nanocomposites as methanol-tolerant oxygen reduction electrocatalyst in alkaline electrolyte

A novel VN/C nanostructure consisting of VN nanoparticles and graphite-dominant carbon layers is synthesized by nitridation of V₂O₅ using melamine as reductant under inert atmosphere. High crystalline VN nanoparticles are observed to be uniformly distributed in carbon layers with an average size of ca13.45 nm. Moreover, the electrocatalytic performance of VN/C towards oxygen reduction reaction (ORR) in alkaline electrolyte is fascinating. The results show that VN/C has a considerable ORR activity, including a 75 percent value of the diffusion-limited current density and a 0.11 V smaller value about the onset potential with respect to Pt/C catalyst. Moreover, the excellent methanol-tolerance performance of VN/C has also been verified with 3 M methanol. Combined with the competitive prices, this VN/C nanocomposite can serve as an appropriate non-precious methanol-tolerant ORR catalyst for alkaline fuel cells.

Tunable dielectric properties of ferrite-dielectric based metamaterial

A ferrite-dielectric metamaterial composed of dielectric and ferrite cuboids has been investigated by experiments and simulations. By interacting with the electromagnetic wave, the Mie resonance can take place in the dielectric cuboids and the ferromagnetic precession will appear in the ferrite cuboids. The magnetic field distributions show the electric Mie resonance of the dielectric cuboids can be influenced by the ferromagnetic precession of ferrite cuboids when a certain magnetic field is applied. The effective permittivity of the metamaterial can be tuned by modifying the applied magnetic field. A good agreement between experimental and simulated results is demonstrated, which confirms that these metamaterials can be used for tunable microwave devices.

Genetic and genomic interactions of animals with different ploidy levels

Polyploid animals have independently evolved from diploids in diverse taxa across the tree of life. We review a few polyploid animal species or biotypes where recently developed molecular and cytogenetic methods have significantly improved our understanding of their genetics, reproduction and evolution. Mitochondrial sequences that target the maternal ancestor of a polyploid show that polyploids may have single (e.g. unisexual salamanders in the genus Ambystoma) or multiple (e.g. parthenogenetic polyploid lizards in the genus Aspidoscelis) origins. Microsatellites are nuclear markers that can be used to analyze genetic recombinations, reproductive modes (e.g. Ambystoma) and recombination events (e.g. polyploid frogs such as Pelophylax esculentus). Hom(e)ologous chromosomes and rare intergenomic exchanges in allopolyploids have been distinguished by applying genome-specific fluorescent probes to chromosome spreads. Polyploids arise, and are maintained, through perturbations of the 'normal' meiotic program that would include pre-meiotic chromosome replication and genomic integrity of homologs. When possible, asexual, unisexual and bisexual polyploid species or biotypes interact with diploid relatives, and genes are passed from diploid to polyploid gene pools, which increase genetic diversity and ultimately evolutionary flexibility in the polyploid. When diploid relatives do not exist, polyploids can interact with another polyploid (e.g. species of African Clawed Frogs in the genus Xenopus). Some polyploid fish (e.g. salmonids) and frogs (Xenopus) represent independent lineages whose ancestors experienced whole genome duplication events. Some tetraploid frogs (P. esculentus) and fish (Squaliusalburnoides) may be in the process of becoming independent species, but diploid and triploid forms of these 'species' continue to genetically interact with the comparatively few tetraploid populations. Genetic and genomic interaction between polyploids and diploids is a complex and dynamic process that likely plays a crucial role for the evolution and persistence of polyploid animals. See also other articles in this themed issue.

Intergenomic translocations in unisexual salamanders of the genus Ambystoma (Amphibia, Caudata)

Intergenomic interactions that include homoeologous recombinations and intergenomic translocations are commonly observed in plant allopolyploids. Homoeologous recombinations have recently been documented in unisexual salamanders in the genus Ambystoma and revealed exchanged chromosomal segments between A. laterale and A.jeffersonianum genomes in individual unisexuals. We discovered intergenomic translocations in two widespread unisexual triploids A.laterale--2 jeffersonianum (or LJJ) and its tetraploid derivative A.laterale--3 jeffersonianum (or LJJJ) by genomic in situ hybridization (GISH). Two different types of intergenomic translocations were observed in two unisexual populations and one contained novel chromosomes generated by an intergenomic reciprocal translocation. We also observed chromosome deletions in several individuals and these chromosome fragmentations were all derived from the A. jeffersonianum genome. These observed intergenomic reciprocal translocations are believed to be caused by non-homologous pairing during meiosis followed by breakage-rejoining events. Genomes of unisexual Ambystoma undergo complicated structural changes that include various intergenomic exchanges that offer unisexuals genetic and phenotypic complexity to escape their evolutionary demise. Unisexual Ambystoma have persisted as natural nuclear genomic hybrids for about four million years. These unisexuals provide a vertebrate model system to examine the interaction of distinct genomes and to evaluate the corresponding genetic, developmental and evolutionary implications of intergenomic exchanges. Intergenomic translocations and homoeologous recombinations appear to be frequent chromosome reconstruction events among unisexual Ambystoma.

Identification of intergenomic recombinations in unisexual salamanders of the genus Ambystoma by genomic in situ hybridization (GISH)

Unisexual salamanders in the genus Ambystoma (Amphibia, Caudata) are endemic to eastern North America and are mostly all-female polyploids. Two to four of the bisexual species, A. laterale, A. jeffersonianum, A. texanum and A. tigrinum, contribute to the nuclear genome of unisexuals and more than 20 combinations that range from diploid to pentaploid have been identified in this complex. Because the karyotypes of the four bisexual species are similar, homologous and homoeologous chromosomes in the unisexuals can not be distinguished by conventional or banded karyotypes. We chose two widespread unisexual genomic combinations (A.laterale-2 jeffersonianum [or LJJ] and A. 2 laterale-jeffersonianum [or LLJ]) and employed genomic in situ hybridization (GISH) to identify the genomes in these unisexuals. Under optimum conditions, GISH reliably distinguishes the respective chromosomes attributed to both A.laterale and A. jeffersonianum. Of four populations examined, two were found to have independently evolved homoeologous recombinants that persist in both LJJ and LLJ individuals. Our results refute the previous hypothesis of clonal integrity and independent evolution of the genome combinations in these unisexuals. Our data provide evidence for intergenomic interactions between maternal chromosomes during meiosis in unisexuals and help to explain previously observed non-homologous bivalents and/or quadrivalents among lampbrush chromosomes that were possibly initiated by partial homosequential pairing among the homo(eo)logues. To explore the utility of GISH in other members of the complex, probes developed from A. laterale were also applied to unisexuals that contained A. tigrinum and A. texanum genomes. GISH is an effective tool that can be used to identify and to quantify genomic constituents and to investigate intergenomic interactions in unisexual salamanders. GISH also has potential application to examine possible genomic evolution in other unisexuals.

Detection of virulence associated genes in clinical strains of vibrio mimicus

A total of 42 clinical strains of Vibrio mimicus were examined for the presence of virulence associated genes toxR, toxS, toxT, tcpP, ctx and tcpA by PCR assay. Almost all strains were shown to have the toxR gene, while the toxS gene was found in 27 strains. On the other hand, five strains possessed both toxT and tcpP genes, but others had neither. Only two strains were positive for amplification of the ctx gene, whereas no PCR product with tcpA primers was detected. The results indicate the incomplete copies of virulence cascade in V mimicus strains. The pathogenesis and epidemic potential of this species is also discussed.

[Pharmacodynamics study of suanzaoren decoction extracted by different technological process]

OBJECTIVE

To select the optimal technological process for Suanzaoren decoction.

METHOD

The effects of extracts from different technological processes on spontaneous motion and sleep time in mice induced by pentobarbital sodium (subthreshold dosage) were studied.

RESULTS

Both the decoction and 95% alcohol extract of Suanzaoren possess sedative and hypnotic effects.

CONCLUSION

Suanzaoren aqueous decoction was selected as the optimal technological process.

Determination of Danshensu, a major active compound of Radix Salvia miltiorrhiza in dog plasma by HPLC with fluorescence detection

A simple and sensitive high performance liquid chromatography method has been developed for the determination of Danshensu (3, 4-dihydroxyphenyllactic acid) in dog plasma. Plasma samples were extracted with ethyl acetate. Analysis of the extracts was performed on a reversed-phase column with an aqueous phosphate buffer-acetonitrile (93:7, v/v) mobile phase, and 4-hydroxybenzoic acid was used as the internal standard. Fluorescence detection at 285 nm (excitation) and 320 nm (emission) was employed. Standard curves were linear in the range from 0.125 to 11.3 microg/mL (regression coefficient r > 0.993) on three different days. Mean recovery was determined as 96.4% by analysis of plasma standard containing 0.63, 5.65 and 11.3 microg/mL of Danshensu. The inter-day precision (RSD) ranged from 3.4 to 8.6% at concentrations of 0.125, 1.88, 6.28 and 11.3 microg/mL, and the intra-day precision was better than 7.2%. The detection and quantitation limits were 0.063 and 0.125 microg/mL, respectively. This validated assay was applied to the determination of Danshensu concentration in dog plasma after oral administration of Radix Salvia miltiorrhiza extracts.

Vav1/Rac-dependent actin cytoskeleton reorganization is required for lipid raft clustering in T cells

Formation of the immunological synapse (IS) in T cells involves large scale molecular movements that are mediated, at least in part, by reorganization of the actin cytoskeleton. Various signaling proteins accumulate at the IS and are localized in specialized membrane microdomains, known as lipid rafts. We have shown previously that lipid rafts cluster and localize at the IS in antigen-stimulated T cells. Here, we provide evidence that lipid raft polarization to the IS depends on an intracellular pathway that involves Vav1, Rac, and actin cytoskeleton reorganization. Thus, lipid rafts did not translocate to the IS in Vav1-deficient (Vav1-/-) T cells upon antigen stimulation. Similarly, T cell receptor transgenic Jurkat T cells also failed to translocate lipid rafts to the IS when transfected with dominant negative Vav1 mutants. Raft polarization induced by membrane-bound cholera toxin cross-linking was also abolished in Jurkat T cells expressing dominant negative Vav1 or Rac mutants and in cells treated with inhibitors of actin polymerization. However, Vav overexpression that induced F-actin polymerization failed to induce lipid rafts clustering. Therefore, Vav is necessary, but not sufficient, to regulate lipid rafts clustering and polarization at the IS, suggesting that additional signals are required.

Immunolocalisation of phospholipase D1 on tubular vesicular membranes of endocytic and secretory origin

We have examined the localisation of overexpressed phospholipase D1 (PLD1) using antibodies against its amino- and carboxyl-terminal domains. PLD1 overexpressed in COS-7 cells showed variable distribution by immunofluorescence but was mainly in punctate structures in the perinuclear region and at the plasma membrane. Downregulation by an anti-sense plasmid resulted in almost exclusively perinuclear distribution in punctate structures that contained immunoreactivity for the endogenous KDEL receptor and the early endosomal antigen EEA1 protein. Influenza haemagglutinin (HA) and HA-derived mutants designed to locate primarily to secretory or endocytic membranes were present in PLD1-positive membranes. Immunofluorescence analysis in permanent CHO cell lines that express PLD1 inducibly confirmed the presence of PLD1 on both endocytic and secretory membranes. Analysis of PLD1 distribution by immunocytochemistry and electron microscopy of intact CHO cells and of isolated membranes revealed that PLD1 was present in tubulovesicular elements and multivesicular bodies. Some of these were close to the Golgi region whereas others stained positive for endocytic cargo proteins. Morphometric analysis assigned the majority of PLD1 immunoreactivity on endosomal membranes and a smaller amount on membranes of secretory origin. PLD1, via signals that are currently not understood, is capable of localising in tubulovesicular membranes of both endocytic and secretory origin.

Antigen-induced translocation of PKC-theta to membrane rafts is required for T cell activation

Protein kinase C-theta (PKC-theta) is essential for mature T cell activation; however, the mechanism by which it is recruited to the TCR signaling machinery is unknown. Here we show that T cell stimulation by antibodies or peptide-major histocompatibility complex (MHC) induces translocation of PKC-theta to membrane lipid rafts, which localize to the immunological synapse. Raft translocation was mediated by the PKC-theta regulatory domain and required Lck but not ZAP-70. In addition, PKC-theta was associated with Lck in the rafts. An isolated PKC-straight theta catalytic fragment did not partition into rafts or activate the transcription factor NF-kappa B, although addition of a Lck-derived raft-localization sequence restored these functions. Thus, physiological T cell activation translocates PKC-theta to rafts, which localize to the T cell synapse; this PKC-theta translocation is important for its function.

[Determination of forsythin, chlorogenic acid and baicalin in jieduxuantou decoction by RP-HPLC]

RP-HPLC was adopted in determination of forsythin, chlorogenic acid and baicate in Jieduxuantou decoction.

Membrane lipid microdomains and the role of PKCtheta in T cell activation

Productive T cell activation depends on the assembly of a highly ordered and compartmentalized immunological synapse or supramolecular activation complex (SMAC). Reorganization of the actin cytoskeleton and clustering of specialized membrane microdomains, or lipid rafts, occur early following TCR/CD3 and costimulatory receptor ligation. Many key signaling molecules localize in lipid raft patches during T cell activation. Lipid raft reorganization is required for T cell activation, where it plays an apparently important role in stabilizing the T cell synapse. Here we review recent evidence supporting the role of lipid rafts in T cell activation. Particular emphasis is placed on the coupling of protein kinase C-theta(PKCtheta), which is selectively expressed in T cells and is known to function as an essential signal for T cell activation, and lipid rafts.

[Quality evaluation of indigowoad root and leaf by chemical pattern recognition]

27 samples of indigowoad root and 5 samples of indigowoad leaf from different species and in different habital were collected. The chemical constituents were analyzed by HPLC, and ten original chemical features as a whole obtained. Meanwhile, extrinsic bacteriostasis experiments were carried out for each of the 32 samples. Canonical correlation analysis was applied to the intercorrelation between the chemical and the pharmacologic data, and five chemical features were found to be the effective constituents. In the end, the 32 samples were divided into five classes by the fuzzy clustering technique ISODATA(interachive self-organizing data analysis technique A).

Analysis of Vibrio mimicus clinical strains by arbitrarily primed polymerase chain reaction

A total of 51 Vibrio mimicus clinical strains from different geographic locations were examined by arbitrarily primed polymerase chain reaction (AP-PCR). The primer VMH-3 divided them into 28 groups, although 18 groups consisted of a single strain at present. All groups had a common 1.0-kb amplification fragment. Most of the groups consisted of strains from same region, although two exceptional groups showed a few amplification fragments including strains from different regions. AP-PCR groups were not consistently associated with serogroups. AP-PCR is thought to be a valuable and easy method for the epidemiological study of V. mimicus.

A precolumn derivatization high-performance liquid chromatographic method with improved sensitivity and specificity for the determination of astragaloside IV in Radix Astragali

A reversed-phase high-performance liquid chromatographic method is developed for the determination of astragaloside (AGS) IV, which is known as the active constituent of Radix Astragali. The method uses precolumn derivatization with benzoyl chloride to form the benzoyl ester of AGS IV quantitatively and is carried out with a wide-ranging concentration (0.004-0.080 mg/mL) of the derivatized AGS IV. The eluent consists of 90% methanol, 4% tetrahydrofuran, 6% water, and 0.2% triethylamine, with vitamin D3 added as the internal standard.

Determination of resibufogenin and cinobufagin in heart-protecting musk pill by HPLC

A high-performance liquid chromatographic (HPLC) method for the simultaneous determination of resibufogenin and cinobufagin in traditional Chinese medicine (heart-protecting musk pill, shexiang baoxin wan in Chinese) was developed. A reversed-phase system with a Hypersil (ODS2) C(18) column and tetrahydrofuran: methanol: water (8:31:61) mobile phase was employed for the separation of resibufogenin and cinobufagin. The detection was set at 299 nm and ethinyl estradiol was chosen as the internal standard. The limit of detection was 1.5 ng for resibufogenin and 2.0 ng for cinobufagin at a signal-to-noise ratio of 4:1. It is a rapid, simple and accurate method for quantitative analysis of resibufogenin and cinobufagin in heart-protecting musk pill.

[Drug resistance of acute promyelocytic leukemia (APL) to all-trans retinoic acid (ATRA) and its reversion]

OBJECTIVE

To study the mechanism of drug resistance of APL to ATRA and the methods of reversion.

METHODS

ATRA-resistant HL60 cell line and bone marrow (BM) leukemia cells from recurrent APL patients who did not respond to ATRA treatment were used in this study. Multiple drug resistance gene (mdr1) expression was determined by RT-PCR and flow cytometry. Cell proliferation and differentiation were assessed by MTT uptake and NBT reduction respectively.

RESULTS

The response of ATRA-resistant HL60 and APL cells from recurrent patients to the differentiation inducing activity of ATRA was significantly reduced, and ATRA had little effect on cell proliferation. Expression of mdr-1 was nagative in ATRA-resistant HL60 cells. It was negative in resistant APL cells even after ATRA treatment. Arsenic trioxide and homoharringtonine (HHT) could inhibit proliferation of HL60 and ATRA-resistant HL60 cells, indicating no cross-resistance with ATRA. Interferon alpha (IFN-alpha) and PGE1 could significantly inhibit proliferation of ATRA-resistant HL60 cells and restore cell differentiation induced by ATRA.

CONCLUSION

Drug resistance of APL to ATRA is not related to mdr-1. It can be reversed by IFN-alpha. There is no cross-resistance between HHT or arsenic trioxide and ATRA.

Inhibition of the c-Jun N-terminal kinase/AP-1 and NF-kappaB pathways by PICOT, a novel protein kinase C-interacting protein with a thioredoxin homology domain

Protein kinase C-theta (PKCtheta) is a Ca(2+)-independent PKC isoform that is selectively expressed in T lymphocytes (and muscle), and is thought to play an important role in T cell receptor-induced activation. To gain a better understanding of the function and regulation of PKCtheta, we have employed the yeast two-hybrid system to identify PKCtheta-interacting proteins. We report the isolation and characterization of a cDNA encoding a novel 335-amino acid (37. 5-kDa) PKCtheta-interacting protein termed PICOT (for PKC-interacting cousin of thioredoxin). PICOT is expressed in various tissues, including in T cells, where it colocalizes with PKCtheta. PICOT displays an N-terminal thioredoxin homology domain, which is required for the interaction with PKC. Comparison of the unique C-terminal region of PICOT with expressed sequence tag data bases revealed two tandem repeats of a novel domain that is highly conserved from plants to mammals. Transient overexpression of full-length PICOT (but not its N- or C-terminal fragments) in T cells inhibited the activation of c-Jun N-terminal kinase (but not extracellular signal-regulated kinase), and the transcription factors AP-1 or NF-kappaB. These findings suggest that PICOT and its evolutionary conserved homologues may interact with PKC-related kinases in multiple organisms and, second, that it plays a role in regulating the function of the thioredoxin system.

Phospholipase D as an effector for ADP-ribosylation factor in the regulation of vesicular traffic

A mammalian phospholipase D (PLD) activity that is stimulated by ADP-ribosylation factor (ARF) has been identified in Golgi-enriched membrane fractions. This activity is due to the PLD1 isoform and evidence from several laboratories indicates that PLD1 is important for the polymerization of vesicle coat proteins on membranes. When expressed in Chinese hamster ovary cells, PLD1 localized to dispersed small vesicles that overlapped with the location of the ERGIC53 protein, a marker for the endoplasmic reticulum (ER)-Golgi intermediate compartment. Cells having increased PLD1 expression had accelerated anterograde and retrograde transport between the ER and Golgi. Membranes from cells having elevated PLD1 activity bound more COPI, ARF, and ARF-GTPase activating protein. These membranes also produced more COPI vesicles than did membranes from control cells. It is likely that PLD1 participates in both positive and negative feedback regulation of the formation of COPI vesicles and is important for controlling the rate of this process.

[Application of statistical simulation spectrophotometry to the determination of four medicaments in feibaosanxiao tablets]

The steps of statistical simulation spectrophotometry are to build a model based on a collection of limited but sufficient data from simulation samples to reveal the real absorbance-concentration relationship of the real sample and provide concentrated data of the individual components of the real sample measured by its absorbance data at several sensitive wavelengths. In this article, the method of stepwise regression has been used for building absorbance-concentration model of Feibaosanxiao tablets, a compound formulation of multimedicaments, and uniform design, for experimental design and recovery test. Recoveries of the four medicaments, acetaminophen, phenytoin sodium, theophylline and caffeine were 99.6%, 97.4%, 100.7% and 100.7% with RSD 0.3%, 1.9%, 1.3% and 1.3% respectively (n = 14).

Phosphatidic acid formation by phospholipase D is required for transport from the endoplasmic reticulum to the Golgi complex

BACKGROUND

Lipid molecules may play a regulatory role in the secretory pathway of mammals and yeast. The lipid hydrolase phospholipase D (PLD) is one candidate for mediating regulation of secretion, based on the location of this enzyme and its requirements for activation.

RESULTS

We found that primary alcohols, which block formation of phosphatidic acid (PA) by PLD, inhibited the transport of two different viral glycoproteins from the endoplasmic reticulum to the Golgi complex in Chinese hamster ovary cells. Corresponding secondary alcohols, which are much less potent in blocking PA formation, were also less effective in blocking transport of the glycoproteins. The block in glycoprotein transport imposed by primary alcohols was reversed when PA, in the form of liposomes, was exogenously supplied to the culture medium.

CONCLUSIONS

We suggest that the earliest site of regulation of membrane transport by PLD is within the intermediate compartment between the endoplasmic reticulum and the Golgi complex.

The effects of simultaneous atropine and labetalol administration on cardiovascular parameters during anticholinesterase poisoning in anaesthetized cat

The effects of atropine administration during anticholinesterase poisoning on heart rate, blood pressure and electrocardiographic changes (ECG) were studied in the cat. Administration of atropine intravenously during anticholinesterase poisoning caused a significant increase in heart rate and blood pressure; ECG changes were also seen. The simultaneous intravenous administration of atropine and labetalol during anticholinesterase poisoning abolished the increase in blood pressure and heart rate; ECG readings remained normal. It is suggested that labetalol may be a useful adjuvant in the treatment of anticholinesterase poisoning especially in patients with compromised heart function.