Neuroprotective Effects of Sinomenine on Experimental Autoimmune Encephalomyelitis via Anti-Inflammatory and Nrf2-Dependent Anti-Oxidative Stress Activity

Multiple sclerosis (MS) is an autoimmune inflammatory disease of the central nervous system (CNS). Sinomenine (SIN), a bioactive alkaloid extracted from the Chinese medicinal plant Sinomenium acutum, has powerful anti-inflammatory and immunosuppressive therapeutic benefits. In our previous research, we found that SIN increased resistance to oxidative stress via the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway in PC12 neuronal cells. However, whether SIN can improve the symptoms and pathological features of experimental autoimmune encephalomyelitis (EAE), a murine model of MS, via the Nrf2 signaling pathway remains unclear. EAE was immunized followed by SIN treatment. Then we evaluated the effects of SIN in EAE. Subsequently, primary microglia were cultured to explore the effect of SIN on microglia activation. Further, the levels of Nrf2 and its downstream molecules were detected to assess the molecular mechanisms of SIN. We demonstrated that SIN effectively ameliorated the severity of EAE, accompanied by a reduction in the demyelination, axonal damage and inhibition of inflammatory cell infiltration. Mechanistically, SIN decreased the inflammatory cytokines expression, and suppressed microglia and astrocytes activation in EAE mice. Furthermore, SIN suppressed lipopolysaccharide (LPS)-induced microglial activation and the production of pro-inflammatory factors in vitro. Moreover, SIN inhibited oxidative stress via the activation of the Nrf2 signaling pathway. Our work proves that SIN exerts its neuroprotective effects by the Nrf2-dependent anti-oxidative stress and diminishing neuroinflammation, suggesting that the "antioxiflammation" effect of SIN is expected to be an ideal treatment strategy for MS/EAE.

The key roles of reactive oxygen species in microglial inflammatory activation: Regulation by endogenous antioxidant system and exogenous sulfur-containing compounds

Aberrant innate immunity in the brain has been implicated in the pathogenesis of several central nervous system (CNS) disorders, including Alzheimer's disease, Huntington's disease, Parkinson's disease, stroke, amyotrophic lateral sclerosis, and depression. Except for extraparenchymal CNS-associated macrophages, which predominantly afford protection against peripheral invading pathogens, it has been reported that microglia, a population of macrophage-like cells governing CNS immune defense in nearly all neurological diseases, are the main CNS resident immune cells. Although microglia have been recognized as the most important source of reactive oxygen species (ROS) in the CNS, ROS also may underlie microglial functions, especially M1 polarization, by modulating redox-sensitive signaling pathways. Recently, endogenous antioxidant systems, including glutathione, hydrogen sulfide, superoxide dismutase, and methionine sulfoxide reductase A, were found to be involved in regulating microglia-mediated neuroinflammation. A series of natural sulfur-containing compounds, including S-adenosyl methionine, S-methyl-L-cysteine, sulforaphane, DMS, and S-alk(enyl)-l-cysteine sulfoxide, modulating endogenous antioxidant systems have been discovered. We have summarized the current knowledge on the involvement of endogenous antioxidant systems in regulating microglial inflammatory activation and the effects of sulfur-containing compounds on endogenous antioxidant systems. Finally, we discuss the possibilities associated with compounds targeting the endogenous antioxidant system to treat neuroinflammation-associated diseases.

CLDN6 Suppresses Migration and Invasion of MCF-7 and SKBR-3 Breast Cancer Cells by Blocking the SMAD/Snail/MMP-2/9 Axis

The study examined the mechanisms of action of signal protein claudin 6 (CLDN6) on migration and invasion of breast cancer cell lines MCF-7 and SKBR-3. To this end, the signal proteins SMAD were blocked with their inhibitor SB431542, the genes CLDN6 and SNAIL were knocked down with short hairpin RNAs, and MMP2 and MMP9 were inhibited with TIMP-1. Expressions of MMP2 and MMP9 mRNAs were evaluated by reverse transcription PCR, Expressions of MMP-2, MMP-9, E-cadherin, N-cadherin, and vimentin were examined by Western blotting. Migration and invasion were analyzed by scratch test and Matrigel invasion assay. SB431542 inhibited expression of MMP2 and MMP9 in both cell lines. Single use of SB431542 inhibited expression of MMP-2/MMP-9 and corresponding mRNAs, but subsequent silencing of CLDN6 gene reversed this effect. TIMP-1 reversed down-regulation of E-cadherin, upregulation of N-cadherin and vimentin, facilitation of migration and invasion evoked by CLDN6 knocking down. Silencing of SNAIL gene inhibited migration and invasion, upregulated the expression of E-cadherin, and down-regulated expression of MMP2, MMP 9, N-cadherin, and vimentin. Thus, CLDN6 suppresses the epithelial-mesenchymal transition, migration, and invasion via blocking SMAD/Snail/MMP-2/9 signaling pathway in MCF-7 and SKBR-3 cancer cell lines.

[Factors analysis of worsening renal function in patients with acute right ventricular myocardial infarction during hospitalization]

Objective: To analyze the related factors of worsening renal function (WRF) in patients with acute right ventricular myocardial infarction (RVMI) during hospitalization. Methods: A total of 98 patients with acute RVMI admitted to the emergency comprehensive ward of Beijing Anzhen Hospital from August 2011 to January 2020 were enrolled in this cross-sectional study. According to the situation of WRF, the patients were divided into non-WRF group (76 cases) and WRF group (22 cases). WRF was defined as ≥0.3 mg/dL increase in serum creatinine level from baseline on day 6 of hospitalization (if hospital stay<6 days, it was at discharge). Baseline data, intravenous fluid infusion, diuretic and significant positive balance of patients' intake and output volume [any 24 h intakes and outputs ≥1 000 ml or any consecutive 72 h intakes and outputs ≥2 000 ml within 6 d of hospitalization (if hospitalization<6 d, it was from admission to discharge)] were obtained, and the differences of above indicators between the two groups were analyzed. Multiple logistic regression model was used to analyze the related factors of WRF. Results: The ages of patients in WRF group and non-WRF group were 60 (50, 68) and 63 (52, 72) years, and the male proportions were 63.6% (14 cases) and 76.3% (58 cases), respectively, and there was no significant difference (all P>0.05). The proportion of positive balance was 31.8% (7 cases) in WRF group, which was higher than 14.5% (11 cases) in non-WRF group (P=0.034). The rate of loop diuretic use in WRF group was 4.5% (1 case), lower than that in non-WRF group 10.5% (8 cases) (P=0.027). After adjusting for age, sex, baseline estimated glomerular filtration rate (eGFR), preoperative isoproterenol/temporary pacemaker/atropine use, significant positive balance of intake and output volume, and loop diuretic use, it was found that eGFR≥60 ml·min^-1·1.73 m^-2 and significant positive balance were associated with WRF, the OR (95%CI) were 0.71 (0.62-0.86) and 1.21 (1.02-1.43) (both P<0.05); After eliminating the variable of significant positive balance in the above model, loop diuretic use was found to be a correlation factor for WRF, with an OR (95%CI) of 0.89 (0.72-0.97) (P<0.05). Conclusions: Significant positive balance of intake and output volume during hospitalization in patients with acute RVMI is a risk factor for WRF on day 6 or at discharge. In the presence of a significant positive balance, loop diuretic use is a protective factor for WRF.

Alkyl-Terminated Gold Nanoparticles as a Self-Therapeutic Treatment for Psoriasis

We present a self-therapeutic nanoparticle for topical delivery to epidermal keratinocytes to prevent and treat psoriasis. Devoid of known chemical or biological antipsoriatic drugs, this sub-15 nm nanoparticle contains a 3 nm gold core and a shell of 1000 Da polyethylene glycol strands modified with 30% octadecyl chains. When it is applied to imiquimod-induced psoriasis mice without an excipient, the nanoparticle can cross the stratum corneum and preferentially enter keratinocytes. Applying the nanoparticles concurrently with imiquimod prevents psoriasis and downregulates genes that are enriched in the downstream of the interleukin-17 signaling pathway and linked to epidermis hyperproliferation and inflammation. Applying the nanoparticles after psoriasis is established treats the psoriatic skin as effectively as standard steroid and vitamin D analog-based therapy but without hair loss and skin wrinkling. The nanoparticles do not accumulate in major organs or induce long-term toxicity. Our nanoparticle offers a simple, safe, and effective alternative for treating psoriasis.

Immobilising hairpin DNA-conjugated distyryl boron dipyrromethene on gold@polydopamine core-shell nanorods for microRNA detection and microRNA-mediated photodynamic therapy

A novel nanosystem of polydopamine-coated gold nanorods (AuNR@PDA) immobilised with molecules of hairpin DNA-conjugated distyryl boron dipyrromethene (DSBDP) was designed and fabricated for detection of microRNA-21 (miR-21). By using this oncogenic stimulus, the photodynamic effect of the DSBDP-based photosensitiser was also activated. In the presence of miR-21, the fluorescence intensity of the nanosystem was increased due to the dissociation of the conjugate from AuNR@PDA upon hybridisation. The intracellular fluorescence intensity triggered by intracellular miR-21 was in the order: MCF-7 > HeLa > HEK-293, which was in accordance with their miR-21 expression levels. The specificity was demonstrated by comparing the results with those of an analogue with a scrambled DNA sequence. The nanosystem could also result in miR-21-mediated photodynamic eradication of miR-21-overexpressed MCF-7 cells. After intravenous injection of the nanosystem into HeLa tumour-bearing nude mice, the fluorescence intensity of the tumour was increased over 24 h and was about 3-fold stronger than that of the scrambled analogue. Upon irradiation, the nanosystem could also greatly reduce the size of the tumour without causing significant tissue damage in the major organs. The overall results showed that this nanoplatform can serve as a specific and potent theranostic agent for simultaneous miR-21 detection and miR-21-mediated photodynamic therapy.

PM2.5 exposure induces alveolar epithelial cell apoptosis and causes emphysema through p53/Siva-1

OBJECTIVE

This study aims to investigate whether PM2.5 exposure is involved in the induction of alveolar epithelial cell apoptosis and the progression of emphysema in mice, and to further explore its specific molecular mechanism.

MATERIALS AND METHODS

A certain number of PM2.5 exposed mice and normal control mice were selected, and a lung resection operation was performed to collect the pulmonary tissue samples, which were then analyzed by hematoxylin and eosin (H&E) staining assay. Subsequently, the total protein in the pulmonary tissues of mice in PM2.5 exposure group and control group was extracted, and the p53 protein level was detected by Western blot. Meanwhile, in A549 cells, after treatment of different doses of PM2.5, the protein levels of p53, caspase3, and clv-caspase3 were examined by Western blot while the mRNA levels of p53, Siva-1, and clv-caspase3 were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR), respectively. In addition, flow cytometry was carried out to measure the incidence of cell apoptosis, while chromatin immunoprecipitation (ChIP) assay was performed to verify whether p53 binds to the Siva-1 promoter region and thus regulates its transcription process.

RESULTS

H&E staining revealed that PM2.5 exposure caused pathological damage in the pulmonary tissues and the expansion of the spatial structure of alveoli, which led to emphysema in mice. Moreover, p53 protein expression in pulmonary tissue of mice in PM2.5 exposure group was remarkably higher than that in the control group. Subsequently, A549 cells were treated with 0, 25, 50, 100 μg/ml PM2.5 for 48 h, and it was found that, with the increase of PM2.5 exposure dose, the p53 protein level, Siva-1 mRNA level and cell apoptosis rate were all found increased in a dose-dependent manner, which could be partially reversed by transfection of si-p53 in A549 cells. In addition, CHIP experiments confirmed that p53 can bind to the Siva-1 promoter region and directly regulate Siva-1 transcription. In A549 cells, PM2.5 exposure increased the expression of the clv-caspase3 protein, which was reversed by the knockdown of p53; however, simultaneous overexpression of Siva-1 could further increase the clv-caspase3 protein level. Additionally, flow cytometry also revealed that PM2.5 exposure induced apoptosis of alveolar epithelial cells, while the knockdown of p53 reduced that, which could be promoted by the overexpression of Siva-1.

CONCLUSIONS

PM2.5 exposure can promote the transcription of Siva-1 to induce apoptosis of alveolar epithelial cells and accelerate the progression of emphysema in mice by enhancing p53 protein expression.

Oscillating Magnetic Field Regulates Cell Adherence and Endothelialization Based on Magnetic Nanoparticle-Modified Bacterial Cellulose

Despite the widely explored biomaterial scaffolds in vascular tissue engineering applications lately, no ideal platform has been provided for small diameter synthetic vascular grafts mainly due to the thrombosis issue. Endothelium is the only known completely non-thrombogenic material; so, functional endothelialization onto vascular biomaterials is critical in maintaining the patency of vascular networks. Bacterial cellulose (BC) is a natural biomaterial with superior biocompatibility and appropriate hydrophilicity as potential vascular grafts. In previous studies, surface modification of active peptides such as Arg-Gly-Asp (RGD) sequences onto biomaterials has been proven to achieve accelerated and selective endothelial cell (EC) adhesion. In our study, we demonstrated a new strategy to remotely regulate the adhesion of endothelial cells based on an oscillating magnetic field and achieve successful endothelialization on the modified BC membranes. In details, we synthesized bacterial cellulose (BC), magnetic BC (MBC), and RGD peptide-grafted magnetic BC (RMBC), modified with the HOOC-PEG-COOH-coated iron oxide nanoparticles (PEG-IONs). The endothelial cells were cultured on the three materials under different frequencies of an oscillating magnetic field, including "stationary" (0 Hz), "slow" (0.1 Hz), and "fast" (2 Hz) groups. Compared to BC and MBC membranes, the cells on RMBC membranes generally show better adhesion and proliferation. Meanwhile, the "slow" frequency of a magnetic field promotes this phenomenon on RMBC and achieves endothelialization after culture for 4 days, whereas "fast" inhibits the cellular attachment. Overall, we demonstrate a non-invasive and convenient method to regulate the endothelialization process, with promising applications in vascular tissue engineering.

[Influenza virus activates toll-like receptor 7/nuclear factor-κB signaling pathway to regulate airway inflammatory response in patients with acute exacerbation of chronic obstructive pulmonary diseases]

Objective: To explore how influenza A virus (IAV) regulates airway inflammation via activating Toll-like receptor 7(TLR7)/nuclear factor of κB (NF-κB) signaling pathway in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD). Methods: Primary bronchial epithelial cells were isolated and cultured from normal controls and COPD patients. Samples were divided into 6 groups according to different in vitro treatment, including normal epithelial cell group (A), normal cells+IAV group (B), COPD epithelial cell group (C), COPD cells+IAV group (D), normal cells+TLR7 small interference RNA (si-RNA) group (E), COPD cells+TLR7 siRNA group (F). Protein expressions of TLR7 and NF-κB were detected by Western blot after 24h co-culture with IAV and TLR7 siRNA. Interleukin-6 (IL-6) and tumor necrosis factor α (TNF α) were detected by enzyme-linked immunosorbent assay (ELISA). Results: (1) Compared with group A [0.350±0.075 and 0.470±0.034, (53.000±6.532)pg/ml and (17.000±1.625)pg/ml],TLR7, NF-κB protein expression and IL-6, TNF α levels were significantly increased in group B[0.950±0.075 and 1.090±0.078,(185.000±7.874)pg/ml and (32.000±0.838)pg/ml], group C[0.780±0.056 and 0.910±0.045,(138.000±5.100)pg/ml and 29.000±1.323)pg/ml) and group D[1.280±0.031 and 1.540±0.051,(432.000±5.734)pg/ml and (52.000±3.453)pg/ml] (all P<0.01). Compared with group C TLR7, NF-κB protein expression and IL-6, TNF α levels were significantly increased in group D (P<0.01). (2) Compared with the group A[0.530±0.023 and 0.800±0.046,(51.000±0.327)pg/ml and (14.000±0.314)pg/ml], TLR7, NF-κB protein expression and IL-6, TNF α levels were significantly decreased in the group E[0.350±0.047 and 0.510±0.067,(26.000±1.081)pg/ml and(8.000±0.526)pg/ml] (P<0.05). Compared with group C[1.080±0.078 and 1.280±0.034,(125.000±2.249)pg/ml and (28.000±1.010)pg/ml], TLR7, NF-κB protein expression and IL-6, TNF α levels decreased in the group F[0.880±0.056 and 1.040±0.029,(83.000±1.125)pg/ml and (21.000±0.429)pg/ml] (P<0.05). Conclusion: Influenza viruses activate TLR7/NF-κB signaling pathway to regulate airway inflammation storms in patients with acute exacerbation of COPD. New therapeutic targets of acute exacerbation COPD may be studied based on these inflammation responses to influenza viruses.

Nano-Cell Interactions of Non-Cationic Bionanomaterials

Advances in nanotechnology have empowered the design of bionanomaterials by assembling different types of natural biomolecules (e.g., nucleic acids, proteins, and lipids) as building blocks into nanoparticles (NPs) of 1-100 nm in diameter. Such bionanomaterials form the basis of useful nanomedicine applications, such as targeted delivery, gene regulation, molecular diagnostics, and immunomodulation. To achieve optimal performance in these applications, it is imperative that the NPs be delivered effectively to the organs, tissues, and cells of interest. A rational approach to facilitating the delivery of NPs is to develop a detailed and comprehensive understanding in their fundamental interactions with the biological system (or nano-bio interactions). Rigorous nano-bio research can provide mechanistic insights for circumventing the bottlenecks associated with inefficient and nonspecific delivery of NPs, catalyzing the clinical translation of nanomedicines. Cationic liposomes and lipid NPs are conventional carriers of therapeutic cargoes into cells due to their high ability to penetrate the cell membrane, a barrier comprised by an anionic phospholipid bilayer. Yet, cationic NPs tend to cause cytotoxicity and immune responses that may hamper their clinical translation. Contrary to cationic NPs, non-cationic NPs (be they near-neutral or anionic in surface charge) generally exhibit higher biocompatibility but enter mammalian cells in much less pronounced amounts. Intriguingly, some types of non-cationic NPs exhibit high biocompatibility and cellular uptake properties, all attractive features for intracellular delivery. In this Account, we present our studies of the interactions of non-cationic bionanomaterials with cells (or nano-cell interactions). To start with, we introduce the use of near-neutral poly(ethylene glycol)-coated NPs for probing the roles of two rarely explored physicochemical parameters on cellular uptake, namely, extracellular compression and alkylation. We next present the nano-cell interactions of two representative types of anionic bionanomaterials that effectively enter mammalian cells and have found widespread applications in the past decade, including DNA-coated NPs and polydopamine (PDA)-coated NPs. In our cell-based studies, we dissect the route of intracellular trafficking, pathway proteins that dictate cellular uptake, and trafficking of NPs. We further touch on our recent quantitative analysis of the cellular-level distribution of NPs in various organs and tissues of diseased animal models. Our results offer important design rules of NPs for achieving effective intracellular delivery and may even guide us to explore nanomedicine applications that we did not conceive before, such as using DNA-coated NPs for targeting atherosclerotic plaques and PDA-coated plasmonic nanoworms for photothermal killing of cancer cells. We conclude with our perspectives in elucidating nano-bio interactions via a reductionist approach, calling for closer attention to the role of functional groups and more refined studies on the organelle-level distribution of NPs and the genetic basis of in vivo distribution of NPs.

Promoting the Delivery of Nanoparticles to Atherosclerotic Plaques by DNA Coating

Many nanoparticle-based carriers to atherosclerotic plaques contain peptides, lipoproteins, and sugars, yet the application of DNA-based nanostructures for targeting plaques remains infrequent. In this work, we demonstrate that DNA-coated superparamagnetic iron oxide nanoparticles (DNA-SPIONs), prepared by attaching DNA oligonucleotides to poly(ethylene glycol)-coated SPIONs (PEG-SPIONs), effectively accumulate in the macrophages of atherosclerotic plaques following an intravenous injection into apolipoprotein E knockout (ApoE^-/-) mice. DNA-SPIONs enter RAW 264.7 macrophages faster and more abundantly than PEG-SPIONs. DNA-SPIONs mostly enter RAW 264.7 cells by engaging Class A scavenger receptors (SR-A) and lipid rafts and traffic inside the cell along the endolysosomal pathway. ABS-SPIONs, nanoparticles with a similarly polyanionic surface charge as DNA-SPIONs but bearing abasic oligonucleotides also effectively bind to SR-A and enter RAW 264.7 cells. Near-infrared fluorescence imaging reveals evident localization of DNA-SPIONs in the heart and aorta 30 min post-injection. Aortic iron content for DNA-SPIONs climbs to the peak (∼60% ID/g) 2 h post-injection (accompanied by profuse accumulation in the aortic root), but it takes 8 h for PEG-SPIONs to reach the peak aortic amount (∼44% ID/g). ABS-SPIONs do not appreciably accumulate in the aorta or aortic root, suggesting that the DNA coating (not the surface charge) dictates in vivo plaque accumulation. Flow cytometry analysis reveals more pronounced uptake of DNA-SPIONs by hepatic endothelial cells, splenic macrophages and dendritic cells, and aortic M2 macrophages (the cell type with the highest uptake in the aorta) than PEG-SPIONs. In summary, coating nanoparticles with DNA is an effective strategy of promoting their systemic delivery to atherosclerotic plaques.

Nitrogenous compounds produced by catalytic pyrolysis of cyanobacteria over metal loaded MCM-41 with vaporized methanol

The synergistic effect of methanol and an acidic catalyst promotes the production of nitriles and the enrichment of pentadecanenitrile.

TaMIR1139: a wheat miRNA responsive to Pi-starvation, acts a critical mediator in modulating plant tolerance to Pi deprivation

Wheat miRNA member TaMIR1139 targets genes functional in various families and plays crucial roles in regulating plant Pi starvation tolerance. Through regulating target genes at posttranscriptional or translational level, plant miRNAs are involved in mediating diverse biological processes associated with growth, development, and responses to adverse stresses. In this study, we characterized the expression pattern and function of TaMIR1139, a miRNA member of wheat (T. aestivum) under Pi deprivation. TaMIR1139 precursor is also present in N. tabucum, suggesting the conserved nature of miR1139 across monocots and eudicots. TaMIR1139 targets seven genes within different families. The transcripts abundance of TaMIR1139 was induced upon Pi deprivation and the upregulated expression under Pi starvation was downregulated by the Pi recovery treatment, In contrast, the genes targeted by TaMIR1139 exhibited reduced transcripts upon Pi starvation and their downregulated expression was recovered by Pi-recovery condition, suggesting the regulation of them under TaMIR1139 through a cleavage mechanism. TaMIR1139 overexpression conferred the Pi-deprived plants improved phenotype, biomass, photosynthesis, and Pi acquisition. Transcriptome analysis identified numerous genes involving biological process, cellular components, and molecular function were differentially expressed in the TaMIR1139 overexpression lines, which suggests the TaMIR1139-mediated plant Pi starvation tolerance to be associated with the role of miRNA in extensively modulating the transcript profiling. A phosphate transporter (PT) gene NtPT showed significantly upregulated expression in TaMIR1139 overexpression lines; overexpression of it conferred plants improved Pi acquisition upon Pi starvation, suggesting its contribution to the TaMIR1139-mediated plant low-Pi stress resistance. Our investigation indicates that TaMIR1139 is critical in plant Pi starvation tolerance through transcriptionally regulating the target genes and modulating the Pi stress-defensiveness processes.

Wheat miRNA TaemiR408 Acts as an Essential Mediator in Plant Tolerance to Pi Deprivation and Salt Stress via Modulating Stress-Associated Physiological Processes

MicroRNAs (miRNA) families act as critical regulators for plant growth, development, and responses to abiotic stresses. In this study, we characterized TaemiR408, a miRNA family member of wheat (Triticum aestivum), for the role in mediating plant responses to Pi starvation and salt stress. TaemiR408 targets six genes that encode proteins involving biochemical metabolism, microtubule organization, and signaling transduction. 5'- and 3'-RACE analyses confirmed the mRNA cleavage of target genes mediated by this wheat miRNA. TaemiR408 showed induced expression patterns upon Pi starvation and salt stress and whose upregulated expression was gradually repressed by the normal recovery treatments. The target genes of TaemiR408 exhibited reverse expression patterns to this miRNA, whose transcripts were downregulated under Pi starvation and salt stress and the reduced expression was recovered by the followed normal condition. These results suggest the regulation of the target genes under TaemiR408 through a cleavage mechanism. Tobacco lines with TaemiR408 overexpression exhibited enhanced stress tolerance, showing improved phenotype, biomass, and photosynthesis behavior compared with wild type under both Pi starvation and salt treatments, which closely associate increased P accumulation upon Pi deprivation and elevated osmolytes under salt stress, respectively. Phosphate transporter (PT) gene NtPT2 displays upregulated transcripts in the Pi-deprived TaemiR408 overexpressors; knockdown of this PT gene reduces Pi acquisition under low-Pi stress, confirming its role in improving plant Pi taken up. Likewise, NtPYL2 and NtSAPK3, genes encoding abscisic acid (ABA) receptor and SnRK2 protein, respectively, exhibited upregulated transcripts in salt-challenged TaemiR408 overexpressors; knockdown of them caused deteriorated growth and lowered osmolytes amounts of plants upon salt treatment. Thus, TaemiR408 is crucial for plant adaptations to Pi starvation and salt stress through regulating Pi acquisition under low-Pi stress and remodel ABA signaling pathway and osmoprotects biosynthesis under salt stress.

Effect of dexmedetomidine on immune function of patients undergoing radical mastectomy: a double blind and placebo control study

OBJECTIVE

To observe and evaluate the effect of dexmedetomidine on the perioperative immune function of patients undergoing a radical mastectomy.

PATIENTS AND METHODS

124 patients undergoing radical mastectomy were divided into the observation group (treated with dexmedetomidine) and the control group (treated with saline) by randomized digital table and double blinded and randomized design. 10 min before anesthesia induction, the patients in the observation group were injected with dexmedetomidine 0.1 ug.kg-1.min-1. The injection of 0.9% sodium chloride solution was given to the control group at the same rate. In the experiment, the medications of anesthesia induction and anesthesia maintain were identical. Venous blood at five times: T0 (before anesthesia), T1 (6 h after surgery), T2 (24 h after surgery), T3 (48 h after surgery), T4 (72 h after surgery) were collected. ELISA (Enzyme Linked Immunosorbent Assay) was used to detect concentrations of IL-2, IFN-γ, IL-4, IL-6 and IL-10; FACS flow cytometry was used to determine the level of T-lymphocyte subsets (CD3+, CD4+, CD8+) and NK cells.

RESULTS

Compared with the control group, the cell levels of CD3+ and CD4+ in the observation group rose remarkably at T3 and T2 (p<0.05). The cell level of CD8+ fell at T2 with significant difference; NK cell level increased noticeably at T1 and T2, and CD4+/CD8+ rose dramatically at all postoperative time points. Obviously, the patients' immune function, to some extent, has been affected; in addition, the concentration of INF-γ in observation group increased prominently at T1, T2 and T3 (p<0.05), and the concentration of IL-2 at T2, IL-10 at T1 and T2, and IL-6 at T2 and T3 in the observation group all rose significantly (p<0.05), and less cytokine Th1 drifted to Th2.

CONCLUSIONS

The dexmedetomidine can effectively maintain the homeostasis of cell immune function of patients undergoing a radical mastectomy.

What determines the interfacial configuration of Nb/Al2O3 and Nb/MgO interface

Nb films are deposited on single crystal Al₂O₃ (110) and MgO(111) substrates by e-beam evaporation technique. Structure of Nb films and orientation relationships (ORs) of Nb/Al₂O₃ and Nb/MgO interface are studied and compared by the combination of experiments and simulations. The experiments show that the Nb films obtain strong (110) texture, and the Nb film on Al₂O₃(110) substrate shows a higher crystalline quality than that on MgO(111) substrate. First principle calculations show that both the lattice mismatch and the strength of interface bonding play major roles in determining the crystalline perfection of Nb films and ORs between Nb films and single crystal ceramic substrates. The fundamental mechanisms for forming the interfacial configuration in terms of the lattice mismatch and the strength of interface bonding are discussed.

Resveratrol improves delayed r-tPA treatment outcome by reducing MMPs

OBJECTIVES

Although recombinant tissue plasminogen activator (r-tPA) is currently the most effective treatment for brain ischemic stroke, the 3-h narrow therapeutic windows severely limits its clinical efficacy. We aim to investigate the effect of resveratrol on improving treatment outcomes of delayed r-tPA administration.

MATERIALS & METHODS

Patients were randomly divided according to their onset-to-treatment time (OTT), as early OTT or delayed OTT. Then, they were either treated with r-tPA + placebo or with r-tPA + resveratrol. Twenty-four hours after the treatment, outcomes were assessed with NIH stroke scale (NIHSS), and plasma levels of MMP-2 and MMP-9 were also examined with ELISA.

RESULTS

In patients receiving delayed r-tPA treatment, co-administration of resveratrol significantly improves their treatment outcomes compared with those receiving placebo, as indicated by improved NIHSS scores. This improved outcome was be caused by resveratrol-induced reduction in plasma levels of both matrix metalloproteinase (MMP)-2 and MMP-9, as a positive correlation was observed between reductions in both MMPs and patient NIHSS scores.

CONCLUSIONS

Resveratrol could be potentially administered as an adjuvant with r-tPA treatment, which extends the clinical therapeutic window of r-tPA, therefore improving the outcome of patients receiving late stroke treatment.

Efficient and intuitive method for the analysis of light scattering by a resonant nanostructure

We present a semi-analytical formalism capable of handling the coupling of electromagnetic sources, such as point dipoles or free-propagating fields, with various kinds of dissipative resonances with radiation leakage, Ohmic losses or both. Due to its analyticity, the approach is very intuitive and physically-sound. It is also very economic in computational resources, since once the resonances of a plasmonic or photonic resonator are known, their excitation coefficients are obtained analytically, independently of the polarization, frequency or location of the excitation source. To evidence that the present formalism is very general and versatile, we implement it with the commercial software COMSOL, rather than with our in-house numerical tools.

First Report of Volutella Blight on Pachysandra Caused by Volutella pachysandricola in China

Pachysandra (Pachysandra terminalis, Buxaceae) and Japanese Pachysandra, also called Japanese Spurge, is a woody ornamental groundcover plant distributed mostly in Zhejiang, Guizhou, Henan, Hubei, Sichuan, Shanxi, and Gansu provinces in China. In April 2010, P. terminalis asymptomatic plants were shipped from Beijing Botanical Garden Institute of Botany Chinese Academy of Science to the garden nursery of Jilin Agricultural University (43°48'N, 125°23'E), Jilin Province. In June 2011, Volutella blight (sometimes called leaf blight and stem canker) of P. terminalis was observed on these plants. Infected leaves showed circular or irregular, tan-to-brown spots often with concentric rings and dark margins. The spots eventually grew and coalesced until the entire leaf died. Cankers appeared as greenish brown and water-soaked diseased areas, subsequently turning brown or black, and shriveled and often girdled the stems and stolons. During wet, humid weather in autumn, reddish orange, cushion-like fruiting structures of the fungus appeared on the stem cankers and undersides of leaf spots. Symptoms of the disease were consistent with previous descriptions (2-4). Five isolates were obtained from necrotic tissue of leaf spots and cankers of stems and stolons and cultured on potato dextrose agar. The colony surface was salmon colored and slimy. Conidia were hyaline, one celled, spindle shaped, and 12.57 to 22.23 × 3.33 to 4.15 μm with rounded ends. Morphological characteristics of the fungus were consistent with the description by Dodge (2), and the fungus was identified as Volutella pachysandricola (telemorph Pseudonectria pachysandricola). The internal transcribed spacer (ITS) regions of the nuclear rDNA were amplified using primers ITS4/ITS5 (1). The ITS sequences were 553 bp long and identical among these five isolates (GenBank Accession No. HE612114). They were 100% identical to Pseudonectria pachysandricola voucher KUS-F25663 (Accession No. JN797821) and 99% identical to P. pachysandricola culture-collection DAOM (Accession No. HQ897807). Pathogenicity was confirmed by spraying leaves of clonally propagated cuttings of P. terminalis with a conidial suspension (1 × 10⁶ conidia/ml) of the isolated V. pachysandricola. Control leaves were sprayed with sterile water. Plants were covered with plastic bags and kept in a greenhouse at 20 to 25°C for 72 h. After 5 to 8 days, typical disease symptoms appeared on leaves, while the control plants remained healthy. V. pachysandricola was reisolated from the leaf spots of inoculated plants. Pachysandra leaf blight and stem canker also called Volutella blight, is the most destructive disease of P. terminalis and previously reported in the northern humid areas of the United States (Illinois, Connecticut, Ohio, Indiana, Iowa, Massachusetts, Missouri, Kentucky, and Wisconsin), northern Europe (Britain, Germany, and Poland), and the Czech Republic. To our knowledge, this is the first report of the disease caused by V. pachysandricola in China. The disease may become a more significant problem in P. terminalis cultivation areas if the disease spreads on P. terminalis in nursery beds. References: (1) D. E. L. Cooke et al. Mycol. Res. 101:667, 1997. (2) B. O. Dodge. Mycologia 36:532, 1944. (3) S. M. Douglas. Online publication. Volutella Blight of Pachysandra. The Connecticut Agricultural Experiment Station, 2008. (4) I. Safrankova. Plant Protect. Sci.43:10, 2007.

First Report of Damping-Off of Rhodiola sachalinensis Caused by Rhizoctonia solani AG-4 HG-II in China

Rhodiola sachalinensis A. Bor (family Crassulaceae), a perennial herbaceous plant, is distributed mainly in the mountainous areas of China, Japan, Korea, and Russia. It is widely used as a traditional Chinese medicine with adaptogenic properties, cardiopulmonary protective effects, and central nervous system activities (3). Currently, it is extensively cultivated in northeastern China. In August 2010, widespread (>60% of plants were symptomatic) damping-off was observed in a seedling field in Linjiang, China. Leaves and stems near the ground were affected first, with dark lesions forming on the stem and the lowest leaves exhibiting wilt. The wilt spread rapidly over the entire plant with leaves becoming grayish brown and water soaked and then turned black and died. Root rot, defoliation, and damping-off were also observed. Six isolates with morphological characteristics of Rhizoctonia solani Kühn were isolated from symptomatic stems when plated on potato dextrose agar (PDA). Mycelium was branched at right angles with a septum near the branch and a slight constriction at the branch base. Fungal colonies were initially white, turned brown with age, and produced irregularly shaped, brown sclerotia after 8 days on PDA. Hyphal cells removed from cultures grown at 25°C on 2% water agar were determined to be multinucleate when stained with 1% safranin O and 3% KOH solution (1) and examined at ×400 magnification. The internal transcribed spacer (ITS) region of the nuclear rDNA was amplified by using the primers ITS4/ITS5 (2). The ITS sequences (715 bp) were identical in these six isolates (GenBank Accession No. FR878087) and had 100% sequence identity with R. solani AG-4 HG-II (GenBank Accession No. HQ629873) along with numerous other accessions from this AG subgroup. Pathogenicity tests were performed on healthy, potted seedlings of R. sachalinensis. Twenty plants were inoculated near the base of the stem with a 0.6-cm-diameter mycelial plug from 3-day-old PDA cultures for each isolate. Twenty plants inoculated with only PDA plugs served as controls. The plants were covered with plastic bags and kept in a greenhouse at 20 to 25°C for 72 h. All inoculated plants showed characteristic symptoms as previously observed in the seedling field 13 days after inoculation, while control plants remained healthy. R. solani AG-4 HG-II was reisolated from symptomatic tissues on inoculated plants. To our knowledge, this is the first report of R. solani AG-4 HG-II causing damping-off on R. sachalinensis in China. References: (1) R. J. Bandoni. Mycologia 71:873, 1979. (2) D. E. L. Cooke et al. Mycol. Res. 101:667, 1997. (3) T. F. Yan et al. Conserv. Genet. 4:213, 2003.

First Report of Leaf Spot Disease on Dictamnus dasycarpus Caused by Phoma dictamnicola in China

Fraxinella, Dictamnus dasycarpus Turcz (Rutaceae), is a perennial herbal plant and mainly distributed in Eurasia and North America. It is often used to treat jaundice, cough, rheumatism, and other diseases and is extensively cultivated in the northeast and northwest of China (3). In June 2009, a severe foliar disease was observed on D. dasycarpus in medicinal plantations in Antu, China. The disease occurred on 100% of the plants and at least 25% of the surface was affected. In the early stages of disease development, symptoms were visible on the top and bottom of infected leaves as small brown spots. Subsequently, these spots became elliptical to irregularly shaped, with beige or grayish white centers and dark brown margins. Within the spots, numerous, dark brown or black, subglobose or ostiolate pycnidia measuring 152 to 367 μm in diameter were observed. Fungal isolates were obtained from the infected leaves on potato dextrose agar (PDA) medium, with conidia that were aseptate or one-septate and ellipsoidal or reniform, measuring approximately 4.7 to 12.6 × 2.1 to 4.5 μm. On the basis of these characteristics, the fungus was identified as a Phoma sp. Four well-sporulating isolates, designated as DdPh-1, DdPh-2, DdPh-3, and DdPh-4, were selected for further studies. The morphological and cultural characteristics of these four isolates were studied as described by Boerema et al. and the fungus was identified as Phoma dictamnicola Boerema et al. (1). The internal transcribed spacer (ITS) region of the nuclear rDNA was amplified and sequenced using primers ITS4/ITS5 (2). All four of the ITS sequences were identical (GenBank Accession No. FR681861) and were 99% identical to P. dictamnicola strains CBS507.91 (Accession No. GU237877) and KACC42445 (Accession No. EF600960). Pathogenicity tests were performed by spraying the leaves of healthy D. dasycarpus plants with a conidial suspension (1 × 10⁶ conidia/ml). Five plants were inoculated with each isolate (DdPh-1, DdPh-2, DdPh-3, and DdPh-4) and five plants were mock inoculated with sterile water. The plants were covered with plastic bags and kept in a greenhouse at 20 to 25° for 72 h. After 9 to 13 days, all inoculated plants showed characteristic symptoms as previously described, while the control plants remained healthy. The fungus was reisolated from the leaf spots of inoculated plants. Currently, the economic importance of this disease is limited, but it may become a more significant problem in production of D. dasycarpus with the cultivation area increasing. The fungus was found in the Netherlands and Korea, but to our knowledge, this is the first report of P. dictamnicola on D. dasycarpus in China. References: (1) G. H. Boerema et al. Phoma Identificatión Manual: Differentiation of Specific and Infra-Specific Taxa in Culture. CABI Publishing. Wallingford, U.K., 2004. (2) D. E. L. Cooke et al. Mycol. Res. 101:667, 1997. (3) S. S. Jiang et al. Biosci. Biotechnol. Biochem. 72:660, 2008.

First Report of Seedling Blight Caused by Rhizoctonia solani on Dioscorea nipponica in China

Throughhill yam (Dioscorea nipponica Makino), a perennial winding herb and a member of the Discoreaceae, is distributed principally in northeast Asia. It is used to produce medicine for treating coronary heart disease, diabetes mellitus, and inflammation. In China, this species is cultivated in many provinces such as Liaoning, Jilin, Heilongjiang, Hebei, Inner Mongolia, and Shanxi. In July 2006, seedling blight was observed on D. nipponica with disease incidence ranging from 37 to 75% in commercial fields in Antu County, China. In the early stages of disease development, water-soaked lesions appeared at the stem base and on leaves near the ground. Lesions later turned dark brown and necrotic. Leaves eventually became chlorotic, stem and petioles collapsed gradually, and plants died. Mycelium was observed to be growing on the surface of infected tissues and adjacent plants, and brown, hard sclerotia were produced on stem or petiole surfaces. A fungus with morphological characteristics of Rhizoctonia solani Kühn was consistently isolated from diseased tissues that were plated on potato dextrose agar (PDA). Mycelium was branched at right angles with a septum near the branch and a slight constriction at the branch base. Cells from hyphae grown on 2% water agar at 25°C were determined to be multinucleate when stained with 1% safranin O and 3% KOH solution (1) and examined at ×400. Anastomosis groups were determined by pairing isolates with 12 tester strains representing all subgroups of AG1 to AG5 on 2% water agar in petri plates (2). The anastomosis grouping of isolates Rs1, Rs2, and Rs5 was determined to be AG1-IB and that of isolates Rs3 and Rs6 was determined to be AG2-1. The rDNA internal transcribed spacer (ITS) gene sequence of isolates Rs1, Rs2, and Rs5 (GenBank Accession Nos. GU585667, GU596490, and GU594691) had 100, 99, and 100% nucleotide identity, respectively, with AG1-IB (GenBank Accession No. FG440191). The rDNA-ITS of isolates Rs3 and Rs6 (GenBank Accession Nos. GU596493 and GU594692) exhibited 99% homology with AG2-1 (GenBank Accession No. EU513135). Pathogenicity tests were performed on healthy, potted 2-year-old plants of D. nipponica. Twenty plants were wound inoculated by placing 0.6-cm mycelial plugs from 3-day-old PDA cultures on leaves and stems. Twenty plants were treated with PDA plugs as controls. Plants were maintained at 25°C and 95% relative humidity on a 12-h light/dark regimen. Typical symptoms of leaf and stem rotting identical to those observed in the commercial field appeared 4 days after inoculation and all inoculated plants died within 10 days. No disease symptoms were observed on control plants. Rhizoctonia solani was consistently reisolated from symptomatic tissues. To our knowledge, this is the first report of R. solani causing seedling blight on D. nipponica in the world. References: (1) R. J. Bandoni. Mycologia 71:873, 1979. (2) C. C. Tu and J. W. Kimbrough. Mycologia 65:941, 1973.

Cis-acting elements responsible for dopaminergic neuron-specific expression of zebrafish slc6a3 (dopamine transporter) in vivo are located remote from the transcriptional start site

The purpose of this study was to analyze the transcriptional regulation of the zebrafish solute carrier family 6 member 3 gene (slc6a3, dopamine transporter, dat), as a first step towards isolating regulatory sequences useful for driving transgene expression within dopaminergic neurons of the zebrafish CNS in vivo. We found that the 3.0 kb slc6a3 mRNA is expressed in each of the major groups of dopaminergic neurons previously identified in the zebrafish CNS. The slc6a3 gene spans >20 kb of genomic DNA and contains 15 exons. The genomic organization of slc6a3 is highly conserved with respect to its human orthologue, including the presence of an untranslated first exon. The promoter lacks a canonical TATA box and there are multiple transcriptional start sites. Functional analysis of cis-acting elements responsible for the expression pattern of slc6a3 was carried out by generating stable transgenic zebrafish lines expressing fluorescent reporters under transcriptional control of fragments of slc6a3 genomic sequence. The region between -2 kb and +5 kb with respect to the transcriptional start site contains the core slc6a3 promoter, in addition to neuronal enhancers and/or non-neuronal repressors that restrict expression to the CNS, but this region lacks cis-acting elements responsible for slc6a3 expression in dopaminergic neurons. The upstream sequence between -6 kb and -2 kb contains an enhancer element that drives slc6a3 expression in dopaminergic neurons of the pretectal region, and additional sequences that partially repress expression in non-dopaminergic neurons. However, expression of slc6a3 in dopaminergic neurons of the ventral diencephalon and telencephalon is dependent on elements that lie outside the region -6 kb to +5 kb. These data provide a detailed analysis of the slc6a3 gene and show that its expression in different populations of dopamine neurons is driven by discrete enhancers, rather than a single target sequence for a terminal factor involved in specifying neurochemical phenotype.

At least two genetically distinct large Babesia species infective to sheep and goats in China

A fatal disease of sheep and goats in the northern part of China has been reported to be due to Babesia ovis. However, some characteristics of the causative agent in recent reports are not in accordance with the original attributes ascribed to this parasite. Therefore, the 18S small subunit ribosomal RNA (18S rRNA) genes of a number of Babesia isolates in China were sequenced and compared with that of other Babesia and Theileria species in an attempt to clarify their taxonomic position. In the present study, seven Babesia isolates were collected from distinct areas of northern China, and the 18S rRNA genes were amplified and sequenced. The phylogenetic trees were inferred based on 18S rRNA gene sequences of the Chinese ovine Babesia isolates and some of ovine Babesia and Theileria species available in GenBank. In the phylogenetic tree, Babesia sp. isolates from Madang, Tianzhu, Lintan, Ningxian, Hebei and Liaoning all grouped with B. motasi with 88.2-99.9% identity, while Babesia sp. Xinjiang grouped in a separate clade between B. ovis and B. crassa with 79.7-81.2% identity. The results indicated that there are at least two distinct Babesia species groups-B. motasi and Babesia sp. Xinjiang, the latter was distinctly different from other ovine Babesia isolates from China with less than 86.6% identity.

Surgical treatment of intractable epilepsy combined with bipolar electrocoagulation on functional cortex

OBJECTIVE

Resecting epileptogenic foci combined with bipolar electrocoagulation of functional cortex has been successfully used to treat intractable epilepsy.

METHOD

124 cases with intractable epilepsy have been treated from 1996 to 1999, 75 cases with temporal lobe epilepsy and 48 cases with extra-temporal lobe epilepsy, and one case with infantile hemiplegia. Electrocorticography (ECoG) was used pre- and postoperatively. 108 cases were followed-up from one to three years.

RESULTS

The general efficiency of bipolar electrocoagulation on functional cortex (BCFC) for epilepsy is 91.7%. The pathological features indicate that the damage by coagulation of the cortex is only in the supra- and infra-granular layers, similar to multiple subpial transection (MST).

CONCLUSION

When the epileptogenic foci are located in functional cortex, the method of resecting the foci combined with BCFC has been effective and improves the results greatly. BCFC is safe and easy to use.

Influence of acetazolamide on AQP1 gene expression in testis and on sperm count/motility in epididymis of rats

Acetazolamide (Ace) is a putative inhibitor of carbonic anhydrase (CA), an enzyme that catalyzes the equilibration of carbon dioxide and carbonic acid and plays a key role in HCO(3)(-) and water reabsorption and acid secretion. Aquaporins (AQPs) are channel-forming membrane glycoproteins that mediate water reabsorption by the renal tubules and other organs of mammals. AQP1 and CAII or CAIV share many common biological properties. Previous studies have shown that AQP1 and CA are located at the same sites in cells of the male reproductive tract. In the present study, Ace at a dose of 40 mg/kg/d x 14, administered per os, suppressed AQP1 gene expression and inhibited CA activity in rat testis. On day 7 of treatment the epididymal sperm motility was significantly reduced, while on day 14 a decrease in sperm count occurred. Ace caused a marked downregulation of AQP1 gene expression; significant suppression occurred on days 7 and 14. Moreover, CA activity was totally blocked throughout the treatment period. The present findings suggest that the reduction of rat sperm motility and count by Ace can be attributed to its capacity to downregulate AQP1 water channel gene expression.

Targeting gene expression using HSV vectors

Herpes simplex virus (HSV) is an encapsulated DNA virus, with many favourable properties for use as a gene transfer vector. For gene therapy applications, it may be desirable to restrict transgene expression to pre-defined subsets of cells. One potential method for achieving targeted transgene expression using the HSV vector system might involve dictating the cell types to which the vector will transfer the therapeutic transgene of interest. HSV delivers its genetic payload to cells directly through the plasmalemma; the mechanisms are complex and involve multiple viral and cell surface determinants. We have investigated several ways in which each component of the cell entry cascade may be manipulated in order to restrict viral DNA and transgene delivery to particular cellular populations. Our results indicate that targeted transduction may be a viable approach to achieving our goal of targeted HSV-mediated transgene expression.

Single-unit neural recording with active microelectrode arrays

This paper discusses the single-unit recording characteristics of microelectrode arrays containing on-chip signal processing circuitry. Probes buffered using on-chip unity-gain operational amplifiers provide an output resistance of 200 ohm with an input-referred noise of 11-muV root-mean-square (rms) (100 Hz-10 kHz). Simultaneous in vivo recordings from single neurons using buffered and unbuffered (passive) iridium recording sites separated by less than 20 microm have shown that the use of on-chip circuitry does not significantly degrade system noise. Single-unit neural activity has also been studied using probes containing closed-loop preamplifiers having a voltage gain of 40 dB and a bandwidth of 13 kHz, and several input dc-baseline stabilization techniques have been evaluated. Low-noise in vivo recordings with a multiplexed probe have been demonstrated for the first time using an external asymmetrical clock running at 200 kHz. The multiplexed system adds less than 8-muV rms of noise to the recorded signals, suppressing the 5-V clock transitions to less than 2 ppm.

[Expression of human papillomavirus DNA in cholesteatoma of the middle ear]

OBJECTIVE

To reveal the role of HPV in the occurrence and development of cholesteatoma of the middle ear.

METHOD

PCR and nuclear acid hybridization were applied in screening 44 cases of middle ear cholesteatoma for detection of HPV DNA, and a comparison analysis with the pathological results of 35 cases of middle ear cholesteatoma was made.

RESULTS

Pathologically, the characteristics of HPV induced-lesions was found in 12 of 35 specimens (34.3%). 44 cases of middle ear cholesteatoma were examined with consensus primers PCR and digoxigenin labeled HPV general probes. HPV DNA positive rates were 29.5% (13/44) and 25.0% (11/44) respectively. HPV DNA positive rate was 58.3% (7/12) and 13.0% (3/23) respectively in 12 cases with pathological characteristics of HPV induced-lesions and in 23 cases without those characteristics. There was significant difference(chi 2 = 7.926, P < 0.005).

CONCLUSIONS

HPV infection can arouse the cleavage and proliferation of cholesteatoma epithelium and may play certain role in the occurrence and development of middle ear cholesteatoma. Aggressive, papillomatous growth and koilocytes can be served as the initial proof of HPV infection in cholesteatoma of the middle ear.

[Thermodynamic characteristics of stoichiometric displacement linear parameter log I in reversed-phase liquid chromatography]

Based on the physical meaning of each term in the linear parameter log I (a constant correlating the affinity of solute to stationary phase) of stoichiometric displacement model for retention(SDM-R) of solute, the thermodynamic characteristics of log I of solute in reversed-phase liquid chromatography (RPLC) were investigated theoretically. This point was tested by experimental data with two linear relationships: (1) plot of log I vs 1/T (T is absolute temperature) with apolar, polar small solutes and proteins; (2) plot of log I vs log Po/w (partition coefficient of solute between n-octanol and water) with apolar and polar small solutes. From the comparison of the magnitude of partition coefficient between small solute and proteins, a phenomenon that the resolution of small solutes depends on column length but that of proteins almost to be independent of column length is quantitatively explained.

Characterization of Microbial Consortia in Paddy Rice Soil by Phospholipid Analysis

Microbial biomass and community structure in paddy rice soil during the vegetation period of rice were estimated by analysis of their phospholipid fatty acids (PLFA), hydroxy fatty acids of lipopolysaccharides (LPS-HYFA), and phospholipid ether lipids (PLEL) directly extracted from the soil. A clear change in the composition of the community structure at different sampling periods was observed, indicated by the principal component analysis of the PLFA. A dramatic decline of ester-linked PLFA was observed in the soil samples taken at the second sampling time. In contrast to the ester-linked PLFA, the non-ester-linked PLFA composition did not change. The hydroxy fatty acids of lipopolysaccharides as well as ether lipids decreased consecutively during the observation period. Total microbial abundance was estimated to be (4.1-7.3) x 10(9) cells g(-1) soil (dry weight). About 44% account for aerobic and 32% for facultative anaerobic bacteria, and 24% for archaea, on average. According to the profile and patterns of PLFA in the soil sample, it may be suggested that the paddy soil at the August sampling period contained more abundant facultative anaerobic bacteria (ca. 36%) and archaea (ca. 37%), but the total microbial biomass was significantly lower than in the remaining sampling periods. As the plant approached maturity, the microbial community structure in the soil changed to contain more abundant Gram-negative bacteria and methanotrophs.

A high-yield microassembly structure for three-dimensional microelectrode arrays

This paper presents a practical microassembly process for three-dimensional (3-D) microelectrode arrays for recording and stimulation in the central nervous system (CNS). Orthogonal lead transfers between the micromachined two-dimensional probes and a cortical surface platform are formed by attaching gold beams on the probes to pads on the platform using wire-free ultrasonic bonding. The low-profile (150 microns) outrigger design of the probes allows the bonding of fully assembled high-density arrays. Micromachined assembly tools allow the formation of a full 3-D probe array within 30 min. Arrays having up to 8 x 16 shanks on 200-micron centers have been realized and used to record cortical single units successfully. Active 3-D probe arrays containing on-chip CMOS signal processing circuitry have also been created using the microassembly approach. In addition, a dynamic insertion technique has been explored to allow the implantation of high-density probe arrays into feline cortex at high-speed and with minimal traumatic injury.

[Studies on the antitumour effect of Alocasia macrorrhiza]

Models of transplanted tumour in mice and human cancer enograft in nude mice were used to evaluate the antitumour effect of water extract of Alocasia macrorrhiza. Results showed that the inhibitory rate against S180 in mice was 29.38%, and the inhibitory rate against transplantable humman gastroadenitis in nude mice was 51.72%. No antitumour effect was shown against ECA in mice.

Integration host factor and cyclic AMP receptor protein are required for TyrR-mediated activation of tpl in Citrobacter freundii

The tpl gene of Citrobacter freundii encodes an enzyme that catalyzes the conversion of L-tyrosine to phenol, pyruvate, and ammonia. This gene is known to be positively regulated by TyrR. The amplitude of regulation attributable to this transcription factor is at least 20-fold. Three TyrR binding sites, designated boxes A, B, and C, centered at coordinates -272.5, -158.5, and -49.5, respectively, were identified in the upstream region of the tpl promoter. The results of mutational experiments suggest that TyrR binds in cooperative fashion to these sites. The nonavailability of any TyrR site impairs transcription. Full TyrR-mediated activation of tpl required integration host factor (IHF) and the cAMP receptor protein (CRP). By DNase I footprinting, it was shown that the IHF binding site is centered at coordinate -85 and that there are CRP binding sites centered at coordinates -220 and -250. Mutational alteration of the IHF binding site reduced the efficiency of the tpl promoter by at least eightfold. The proposed roles of CRP and IHF are to introduce bends into tpl promoter DNA between boxes A and B or B and C. Multimeric TyrR dimers were demonstrated by a chemical cross-linking method. The formation of hexameric TyrR increased when tpl DNA was present. The participation of both IHF and CRP in the activation of the tpl promoter suggests that molecular mechanisms quite different from those that affect other TyrR-activated promoters apply to this system. A model wherein TyrR, IHF, and CRP collaborate to regulate the expression of the tpl promoter is presented.

[Gene diagnosis of 10 Chinese families with adult polycystic kidney disease from Guangxi region]

OBJECTIVE

To study presymptomatic gene diagnosis in adult polycystic kidney disease (APKD).

METHODS

Linkage analysis and haplotype characterization were carried out in 10 unrelated Chinese APKD families from Guangxi region, including 97 individuals and 29 affected members. Members of these families were ultrasonographically examined. Linkage to PKD1 was investigated in all families with four microsatellite markers(SM7, CW2, AC2.5, and KG8). These flanking markers were amplified by PCR.

RESULTS

The families were fully informative for gene diagnosis and no evidence of genetic heterogeneity was found. DNA analysis predicted 7 asymptomatic individuals(by 28 years old) as being affected, although they all presented negative ultrasonographs.

CONCLUSION

Linkage analysis is still an important way in APKD presymptomatic gene diagnosis.

An unidentified species of Theileria infective for cattle discovered in China

Infection experiments, morphological observations and transmission experiments were conducted with an unidentified Theileria sp. isolated from a naturally infected ox. The results showed that the protozoa could multiply extensively in a splenectomized ox and the parasitaemia could reach 52.69%. The Theileria sp. was polymorphic: being pear-shaped, circular, elliptical, rod-like, comma-shaped, three-leafed- or cross-shaped and having many other irregular-shapes which were seldom detected. In erythrocytes, the anaplasma-like protozoa grew, producing protoplasm which could extend and clump together, and developed into many polymorphic protozoa. Some of the protozoa propagated themselves by budding. The protozoa could not be transmitted by Haemaphysalis longicornis or Hyalomma detritum. The pathogenicity, vector ticks and life cycle of this protozoan are unknown.

Effect of sedative and hypnotic doses of propofol on the EEG activity of patients with or without a history of seizure disorders

Propofol is alleged to possess both pro- and anticonvulsant properties, leading to controversy regarding its use in patients with a history of seizures. Since propofol is administered for both sedation and hypnosis, it is important to understand the effects of low (0.5-1.0 mg/kg) and high (2-2.5 mg/kg) doses of propofol on the electroencephalogram (EEG). In this study, the hemodynamic and EEG effects of cumulative doses of propofol from 0.5 to 2.5 mg/kg i.v. were studied in 30 neurosurgical patients with or without a history of seizure disorders. While continuously recording from scalp EEG electrodes (F3, F4, C3, C4, P3, P4, O1, and O2), propofol 0.5 mg/kg was infused intravenously over 20 s. The same dose of propofol was reinjected four times at 2-min intervals, until a total dose of 2.5 mg/kg had been administered. The number and average amplitude of the EEG waves were counted and measured manually, respectively, from 80 to 90 s after beginning the injection of each dose of propofol. After lower propofol doses (0.5-1 mg/kg), the number of beta-waves increased, while alpha- and theta-waves decreased significantly in all patients. However, with larger doses of propofol (total dose of 2-2.5 mg/kg), the number of beta-waves decreased and delta-waves appeared. The amplitudes of all EEG waves increased and were maintained at a higher level after administration of propofol. Spike (or sharp) waves appeared in 33% of the control patients and in 40% of the epileptic group after propofol 0.5 mg/kg and in 73% of the control and 67% of the epileptic patients after the 1.5-mg/kg dose. In the majority of patients, the spike waves disappeared when additional doses of propofol were administered. One patient in the epileptic group had an EEG-recorded and clinical grand mal seizure after propofol 1 mg/kg, but the seizure disappeared after an additional 0.5-mg/kg bolus dose was administered. The propofol-induced EEG changes appeared initially at the frontal and central EEG electrodes and subsequently at the other EEG electrodes. Overall, there were no significant differences in the spectrum of EEG changes between the two patient populations. It is concluded that propofol produces similar dose-dependent effects on EEG activity in patients with or without a history of seizure disorders. While induction of anesthesia with higher doses of propofol (> 1.5 mg/kg) in neurosurgical patients with well controlled seizure disorder is safe, smaller sedative doses should be administered with caution to epileptic patients.