The effect of sevoflurane exposure on cell-type-specific changes in the prefrontal cortex in young mice.

Sevoflurane, the predominant pediatric anesthetic, has been linked to neurotoxicity in young mice, although the underlying mechanisms remain unclear. This study focuses on investigating the impact of neonatal sevoflurane exposure on cell-type-specific alterations in the prefrontal cortex (PFC) of young mice. Neonatal mice were subjected to either control treatment (60% oxygen balanced with nitrogen) or sevoflurane anesthesia (3% sevoflurane in 60% oxygen balanced with nitrogen) for 2 hours on postnatal days (PNDs) 6, 8, and 10. Behavioral tests and single-nucleus RNA sequencing (snRNA-seq) of the PFC were conducted from PNDs 31 to 37. Mechanistic exploration included clustering analysis, identification of differentially expressed genes (DEGs), enrichment analyses, single-cell trajectory analysis, and genome-wide association studies (GWAS). Sevoflurane anesthesia resulted in sociability and cognition impairments in mice. Novel specific marker genes identified 8 distinct cell types in the PFC. Most DEGs between the control and sevoflurane groups were unique to specific cell types. Re-defining 15 glutamatergic neuron subclusters based on layer identity revealed their altered expression profiles. Notably, sevoflurane disrupted the trajectory from oligodendrocyte precursor cells (OPCs) to oligodendrocytes (OLs). Validation of disease-relevant candidate genes across the main cell types demonstrated their association with social dysfunction and working memory impairment. Behavioral results and snRNA-seq collectively elucidated the cellular atlas in the PFC of young male mice, providing a foundation for further mechanistic studies on developmental neurotoxicity induced by anesthesia.

Dexmedetomidine Infusion Versus Placebo During Light or Deep Anesthesia on Postoperative Delirium in Older Patients Undergoing Major Noncardiac Surgery: A Pilot Randomized Factorial Trial.

BACKGROUND: Postoperative delirium (POD) is common among older surgical patients and may be affected by dexmedetomidine and depth of anesthesia. We designed this pilot study to assess the feasibility of comparing dexmedetomidine with normal saline during light versus deep anesthesia on POD in older patients undergoing major noncardiac surgery. METHODS: In this pilot randomized factorial study, 80 patients aged 60 years or older undergoing major noncardiac surgery were randomized (1:1:1:1) to receive dexmedetomidine infusion 0.5 µg/kg/h or normal saline placebo during light (bispectral index [BIS] target 55) or deep (BIS target 40) anesthesia. Feasibility end points included consent rate and dropout rate, timely enrollment, blinded study drug administration throughout surgery, no inadvertent unmasking, achieving BIS target throughout >70% of surgery duration, and the process of twice-daily POD screening. In addition, we estimated the POD incidences in the 2 control groups (placebo and deep anesthesia) and treatment effects of dexmedetomidine and light anesthesia. RESULTS: Between November 1, 2021, and June 30, 2022, 78 patients completed the trial (mean [standard deviation, SD] age, 69.6 [4.6] years; 48 male patients [62%]; dexmedetomidine-deep, n = 19; dexmedetomidine-light, n = 20; placebo-deep, n = 19; placebo-light, n = 20). This study had a high consent rate (86%) and a low dropout rate (2.5%). Average recruitment was 5 patients at each center per month. Dexmedetomidine and normal saline were administered in a blinded fashion in all patients. Unmasking did not occur in either group. Approximately 99% of patients received the scheduled study drug infusion throughout the surgery. Approximately 81% of patients achieved the BIS targets throughout >70% of the surgery duration. The scheduled twice-daily POD screening was completed without exception. Overall, 10 of the 78 patients (13%; 95% confidence interval [CI], 7%-22%) developed POD. For the 2 reference groups, POD was observed in 7 of the 39 patients (17.9%; 95% CI, 9%-32.7%) in the placebo group and 7 of the 38 patients (18.4%; 95% CI, 9.2%-33.4%) in the deep anesthesia group. Regarding the treatment effects on POD, the estimated between-group difference was -10% (95% CI, -28% to 7%) for dexmedetomidine versus placebo, and -11% (95% CI, -28% to 6%) for light versus deep anesthesia. CONCLUSIONS: The findings of this pilot study demonstrate the feasibility of assessing dexmedetomidine versus placebo during light versus deep anesthesia on POD among older patients undergoing major noncardiac surgery, and justify a multicenter randomized factorial trial.

Single-nucleus Atlas of Sevoflurane-induced Hippocampal Cell Type- and Sex-specific Effects during Development in Mice.

BACKGROUND: Multiple neonatal exposures to sevoflurane induce neurocognitive dysfunctions in rodents. The lack of cell type-specific information after sevoflurane exposure limits the mechanistic understanding of these effects. In this study, the authors tested the hypothesis that sevoflurane exposures alter the atlas of hippocampal cell clusters and have neuronal and nonneuronal cell type-specific effects in mice of both sexes. METHODS: Neonatal mice were exposed to 3% sevoflurane for 2 h at postnatal days 6, 8, and 10 and analyzed for the exposure effects at postnatal day 37. Single-nucleus RNA sequencing was performed in the hippocampus followed by in situ hybridization to validate the results of RNA sequencing. The Morris Water Maze test was performed to test neurocognitive function. RESULTS: The authors found sex-specific distribution of hippocampal cell types in control mice alongside cell type- and sex-specific effects of sevoflurane exposure on distinct hippocampal cell populations. There were important changes in male but not in female mice after sevoflurane exposure regarding the proportions of cornu ammonis 1 neurons (control vs. sevoflurane, males: 79.9% vs. 32.3%; females: 27.3% vs. 24.3%), dentate gyrus (males: 4.2% vs. 23.4%; females: 36.2% vs. 35.8%), and oligodendrocytes (males: 0.6% vs. 6.9%; females: 5.9% vs. 7.8%). In male but not in female mice, sevoflurane altered the number of significantly enriched ligand-receptor pairs in the cornu ammonis 1, cornu ammonis 3, and dente gyrus trisynaptic circuit (control vs. sevoflurane, cornu ammonis 1-cornu ammonis 3: 18 vs. 42 in males and 15 vs. 21 in females; cornu ammonis 1-dentate gyrus: 21 vs. 35 in males and 12 vs. 20 in females; cornu ammonis 3-dentate gyrus: 25 vs. 45 in males and 17 vs. 20 in females), interfered with dentate gyrus granule cell neurogenesis, hampered microglia differentiation, and decreased cornu ammonis 1 pyramidal cell diversity. Oligodendrocyte differentiation was specifically altered in females with increased expressions of Mbp and Mag. In situ hybridization validated the increased expression of common differentially expressed genes. CONCLUSIONS: This single-nucleus RNA sequencing study reveals the hippocampal atlas of mice, providing a comprehensive resource for the neuronal and nonneuronal cell type- and sex-specific effects of sevoflurane during development.

Complement C1q-mediated microglial synaptic elimination by enhancing desialylation underlies sevoflurane-induced developmental neurotoxicity.

BACKGROUND: Repeated neonatal sevoflurane exposures led to neurocognitive disorders in young mice. We aimed to assess the role of microglia and complement C1q in sevoflurane-induced neurotoxicity and explore the underlying mechanisms. METHODS: Neonatal mice were treated with sevoflurane on postnatal days 6, 8, and 10, and the Morris water maze was performed to assess cognitive functions. For mechanistic explorations, mice were treated with minocycline, C1q-antibody ANX005, and sialidase-inhibitor N-acetyl-2,3-dehydro-2-deoxyneuraminic acid (NADNA) before sevoflurane exposures. Western blotting, RT-qPCR, Golgi staining, 3D reconstruction and engulfment analysis, immunofluorescence, and microglial morphology analysis were performed. In vitro experiments were conducted in microglial cell line BV2 cells. RESULTS: Repeated neonatal sevoflurane exposures resulted in deficiencies in learning and cognition of young mice, accompanied by microglial activation and synapse loss. Sevoflurane enhanced microglia-mediated synapse elimination through C1q binding to synapses. Inhibition of microglial activation and phagocytosis with minocycline significantly reduced the loss of synapses. We further revealed the involvement of neuronal sialic acids in this process. The enhanced activity of sialidase by sevoflurane led to the loss of sialic acids, which facilitated C1q binding to synapses. Inhibition of C1q with ANX005 or inhibition of sialidase with NADNA significantly rescued microglia-mediated synapse loss and improved neurocognitive function. Sevoflurane enhanced the engulfment of BV2 cells, which was reversed by ANX005. CONCLUSIONS: Our findings demonstrated that C1q-mediated microglial synaptic elimination by enhancing desialylation contributed to sevoflurane-induced developmental neurotoxicity. Inhibition of C1q or sialidase may be a potential therapeutic strategy for this neurotoxicity.

Triggering Receptor Expressed on Myeloid Cells 2 Alleviated Sevoflurane-Induced Developmental Neurotoxicity via Microglial Pruning of Dendritic Spines in the CA1 Region of the Hippocampus.

Sevoflurane induces developmental neurotoxicity in mice; however, the underlying mechanisms remain unclear. Triggering receptor expressed on myeloid cells 2 (TREM2) is essential for microglia-mediated synaptic refinement during the early stages of brain development. We explored the effects of TREM2 on dendritic spine pruning during sevoflurane-induced developmental neurotoxicity in mice. Mice were anaesthetized with sevoflurane on postnatal days 6, 8, and 10. Behavioral performance was assessed using the open field test and Morris water maze test. Genetic knockdown of TREM2 and overexpression of TREM2 by stereotaxic injection were used for mechanistic experiments. Western blotting, immunofluorescence, electron microscopy, three-dimensional reconstruction, Golgi staining, and whole-cell patch-clamp recordings were performed. Sevoflurane exposures upregulated the protein expression of TREM2, increased microglia-mediated pruning of dendritic spines, and reduced synaptic multiplicity and excitability of CA1 neurons. TREM2 genetic knockdown significantly decreased dendritic spine pruning, and partially aggravated neuronal morphological abnormalities and cognitive impairments in sevoflurane-treated mice. In contrast, TREM2 overexpression enhanced microglia-mediated pruning of dendritic spines and rescued neuronal morphological abnormalities and cognitive dysfunction. TREM2 exerts a protective role against neurocognitive impairments in mice after neonatal exposures to sevoflurane by enhancing microglia-mediated pruning of dendritic spines in CA1 neurons. This provides a potential therapeutic target in the prevention of sevoflurane-induced developmental neurotoxicity.

Novel cathode interlayers based on neutral alcohol-soluble small molecules with a triphenylamine core featuring polar phosphonate side chains for high-performance polymer light-emitting and photovoltaic devices.

A new family of neutral alcohol-soluble small molecular materials comprised of electron-rich triphenylamine (TPA) and fluorene featuring phosphonate side chains (FEP) is reported, namely 3TPA-FEP, 2TPA-2FEP and TPA-3FEP, which have different TPA and FEP contents. Due to their good solubility in polar solvents like alcohol, multilayer devices can be fabricated by a wet process from orthogonal solvents. Polymer light-emitting devices with these materials as a cathode interlayer and Al as the cathode show greatly enhanced efficiencies in contrast to control devices without such a cathode interlayer, and their efficiencies are comparable with or even higher than devices with the low work-function metal Ba/Al as the cathode. In addition, high-performance polymer solar cells based on the poly[N-9''-hepta-decanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT):[6,6]-phenyl C71 -butyric acid methyl ester (PC71 BM) system are also achieved with power conversion efficiencies of 7.21%, 6.90% and 6.89%, by utilizing 3TPA-FEP, 2TPA-2FEP and TPA-3FEP as the cathode interlayer, respectively. These efficiencies are also much higher than those for control devices without the cathode interlayer. Although TPA is well-known as a hole-transport unit, the current findings indicate that alcohol-soluble TPA-based small molecules are also a promising cathode interlayer for both electron injection and extraction.

Novel bipolar host materials based on 1,3,5-triazine derivatives for highly efficient phosphorescent OLEDs with extremely low efficiency roll-off.

Recently, bipolar host materials have attracted considerable attention because they can achieve balanced charge injection/transport in phosphorescent organic light emitting diodes (PhOLEDs) and consequently obtain excellent device performance. In this work, two bipolar host materials, namely, 3-(4,6-diphenyl-1,3,5-triazin-2-yl)-9-phenyl-9H-carbazole (DPTPCz) and 3-(4,6-diphenoxy-1,3,5-triazin-2-yl)-9-phenyl-9H-carbazole (DPOTPCz), have been designed, synthesized and characterized. With high triplet energy levels of 2.78 and 2.86 eV for DPTPCz and DPOTPCz, respectively, two compounds are considered promising bipolar host materials for PhOLEDs. Blue and green PhOLEDs based on these two new compounds show excellent performances. The phosphorescent devices based on DPTPCz exhibit maximum external quantum efficiencies of 14.4% (for blue device) and 21.2% (for green device), and maintain high efficiencies of 11.9% and 20.0% even at a high luminance of 10,000 cd m(-2).

Organocatalytic cycloaddition-elimination cascade for atroposelective construction of heterobiaryls.

The first chiral phosphoric acid (CPA) catalyzed cycloaddition-elimination cascade reaction of 2-naphthol- and phenol-derived enecarbamates with azonaphthalenes has been established, providing a highly atroposelective route to an array of axially chiral aryl-C3-benzoindoles in excellent yields with excellent enantioselectivities. The success of this strategy derives from the stepwise process involving CPA-catalyzed asymmetric formal [3 + 2] cycloaddition and subsequent central-to-axial chirality conversion by elimination of a carbamate. In addition, the practicality of this reaction had been verified by varieties of transformations towards functionalized atropisomers.

Dendritic cells (DCs) transfected with a recombinant adenovirus carrying chlamydial major outer membrane protein antigen elicit protective immune responses against genital tract challenge infection.

Chlamydia trachomatis, an obligate intracellular bacterial pathogen, is the major cause of sexually transmitted diseases worldwide. Although a variety of strategies have been taken to promote the development of a protective vaccine, no ideal vaccine has been generated so far. In this study, we transfected dendritic cells (DCs) with recombinant adenovirus carrying C. trachomatis serovar E major outer membrane protein gene (Ad-MOMP), and investigated their ability to induce specific protection against genital tract chlamydial challenge infection. The results showed that when DCs were transfected with Ad-MOMP in vitro, the DCs exhibited increased expression of CD80 and MHC-II molecules as well as enhanced IL-12 secretion and were able to stimulate T-cell proliferation. The level of IFN-gamma secreted by stimulated T cells was also up-regulated significantly. When the Ad-MOMP transfected DCs were adoptively transferred intravenously to naive mice, they generated Th1-biased cytokine production and mucosal IgA responses specific for C. trachomatis. More importantly, the mice immunized with Ad-MOMP-DC mounted protection against genital tract challenge infection, shown by lower body mass loss, lower chlamydial loads, and less severe pathological changes. In conclusion, Ad-MOMP transfected DCs are capable of inducing effective protective immune responses against C. trachomatis genital infection.

Replication and transcription of human papillomavirus type 58 genome in Saccharomyces cerevisiae.

BACKGROUND: To establish a convenient system for the study of human papillomavirus (HPV), we inserted a Saccharomyces cerevisiae selectable marker, Ura, into HPV58 genome and transformed it into yeast. RESULTS: HPV58 genome could replicate extrachromosomally in yeast, with transcription of its early and late genes. However, with mutation of the viral E2 gene, HPV58 genome lost its mitotic stability, and the transcription levels of E6 and E7 genes were upregulated. CONCLUSIONS: E2 protein could participate in viral genome maintenance, replication and transcription regulation. This yeast model could be used for the study of certain aspects of HPV life cycle.

Copper(I)/DDQ-Mediated Double-Dehydrogenative Diels-Alder Reaction of Aryl Butenes with 1,4-Diketones and Indolones.

A copper(I)/DDQ-mediated double-dehydrogenative Diels-Alder (DDDA) reaction of simple butenes with 1,4-diketones and indolones has been established for the first time. This strategy is based on a tandem double-dehydrogenation/Diels-Alder reaction from nonprefunctionalized starting materials, in which both a diene and dienophile were in situ generated via activation of fourfold inert C(sp3)-H bonds in one catalytic system.

Mutational analysis of proto-oncogene Dbl on Xq27 in testicular germ cell tumors reveals a rare SNP in a patient with bilateral undescended testis.

OBJECTIVES: An abundance of X chromosomes in testicular germ cell tumors (TGCTs), and a candidate TGCTs susceptibility gene (TGCT1) on Xq27 highlight the potential involvement of X chromosomes in TGCT pathogenesis. However, the TGCT1 on Xq27 has so far not been identified. We hypothesized that a somatic mutation of dbl oncogene on Xq27 may play a role for the development of TGCTs. METHODS: We have screened 41 TGCT tissues for dbl mutations using single-strand conformation polymorphism (SSCP) analysis. These tissues are composed of 25 seminomatous TGCTs tissues and 16 non-seminomatous TGCTs tissues, including two cases with a rhabdomyosarcoma component. RESULTS: Somatic mutations were not detected in the 25 exons of dbl in these TGCTs. However, we found a rare single nucleotide polymorphism (SNP) (T to C nucleotide change) within intron 22 in one out of the 41 TGCTs cases (2%). Furthermore, the sample with the rare SNP was identified as the sole TGCTs case associated with bilateral undescended testis in our series. CONCLUSIONS: Our results indicate that proto-oncogene dbl is not a major target for sporadic TGCTs. However, the rare SNP in dbl may affect the susceptibility to undescended testis. Determining the frequency of this SNP in patients with various types of undescended testis in different ethnic groups is a warranted study.

Expression of HPV 58 long and short L1 capsid proteins in primary mouse keratinocyte cultures.

We studied expression of HPV 58 long and short L1 proteins in primary mouse keratinocyte (KC) cultures by transient transfection of the L1 expression constructs. Following transient transfection, long and short L1 open reading frames (ORFs) were transcribed continuously for 9 days; however, no significant difference was detected between the long and short L1 mRNA levels measured by quantitative RT-PCR. Western blot analysis showed that both long and short L1 proteins were continuously detected in L1-transfected KCs for 9 days post-transfection and the significantly increased signals of the L1 proteins over time were associated with KC differentiation. Moreover, L1 protein was more abundant in KCs transfected with the short L1 ORF than the long L1 ORF. In vitro translation of the L1 mRNAs indicated further that the short L1 mRNA had significantly higher translation efficiency than the long L1 mRNA in cell-free lysate system. The L1 proteins expressed from the two L1 mRNAs in KCs were similarly stable. Thus, approximate 40% lower level of expression of the L1 protein in KCs transfected with the long L1 ORF was probably due to a stem-loop structure with high DeltaG value downstream the first AUG codon in its mRNA secondary structure. This stem-loop structure might prevent efficient binding of the ribosome to mRNA and therefore reduced translation.

The antiarrhythmic effect and possible ionic mechanisms of pilocarpine on animal models.

This study was designed to evaluate the effects of pilocarpine and explore the underlying ionic mechanism, using both aconitine-induced rat and ouabain-induced guinea pig arrhythmia models. Confocal microscopy was used to measure intracellular free-calcium concentrations ([Ca(2+)](i)) in isolated myocytes. The current data showed that pilocarpine significantly delayed onset of arrhythmias, decreased the time course of ventricular tachycardia and fibrillation, reduced arrhythmia score, and increased the survival time of arrhythmic rats and guinea pigs. [Ca(2+)](i) overload induced by aconitine or ouabain was reduced in isolated myocytes pretreated with pilocarpine. Moreover, M(3)-muscarinic acetylcholine receptor (mAChR) antagonist 4-DAMP (4-diphenylacetoxy-N-methylpiperidine-methiodide) partially abolished the beneficial effects of pilocarpine. These data suggest that pilocarpine produced antiarrhythmic actions on arrhythmic rat and guinea pig models induced by aconitine or ouabain via stimulating the cardiac M(3)-mAChR. The mechanism may be related to the improvement of Ca(2+) handling.

Periplocoside A, a pregnane glycoside from Periploca sepium Bge, prevents concanavalin A-induced mice hepatitis through inhibiting NKT-derived inflammatory cytokine productions.

Periploca sepium Bge, a traditional Chinese herb medicine, is widely used for treating rheumatoid arthritis in china. Periplocoside A (PSA), a pregnane glycoside, is a new nature product compound isolated from P. sepium Bge. We examined the protective effects of PSA, on concanavaline A (ConA)-induced hepatitis. Pretreatment with PSA dramatically ameliorated ConA-induced liver injury, which was characterized by reducing serum alanine transaminase (ALT), pathogenic cytokines of interleukin (IL)-4 and interferon (IFN)-gamma levels, impeding the liver necrosis, and thus elevating the survival rate. In vitro, PSA inhibited IL-4 and IFN-gamma productions of alpha-galactosylceramide (alpha-GalCer) or anti-CD3-activated Natural killer T (NKT) cells. Enzyme Linked Immunosorbent Assay (ELISA) and Reverse Transcription Polymerase Chain Reaction (RT-PCR) assays revealed PSA suppressed IL-4 transcription and IFN-gamma translation. In conclusion, PSA had significantly preventative effect on ConA-induced hepatitis, which was closely associated with inhibition of NKT-derived inflammatory cytokine productions. These findings suggested that PSA has the therapeutic potential for treatment of human autoimmune-related hepatitis.

Expression of nucleostemin in prostate cancer and its effect on the proliferation of PC-3 cells.

BACKGROUND: Nucleostemin is essential for the proliferation and survival of stem and cancer cells, but it is unknown whether this newly identified molecule is involved in prostate cancer pathogenesis. METHODS: Total RNA and protein were extracted from prostate cancer tissues and PC-3, LNCap and DU145 cell lines. The nucleostemin mRNA and protein expression were measured by RT-PCR and Western blot. Immunohistochemistry was also used to detect the nucleostemin protein expression in prostate cancer tissues and PC-3 cells. A nucleostemin specific, short hairpin RNA, expression plasmid was used to transfect PC-3 cells. The changes of nucleostemin gene were detected and the proliferative capacity of the cells was determined. RESULTS: Nucleostemin was highly expressed in prostate cancer tissues and cell lines. Nucleostemin expression level in the silencer group PC-3 cells remarkably reduced. The proliferation rate of silencer group PC-3 cells decreased and the percentage of G1 stage cells increased. The neoplasm forming capacity in nude mice of the silencer group PC-3 cells decreased significantly. CONCLUSIONS: Nucleostemin is highly expressed in prostate cancer tissues and cell lines. The proliferative capacity of PC-3 cells is remarkably reduced after silencing nucleostemin gene expression.

[Spatial Variation of Heavy Metals in Soils and Its Ecological Risk Evaluation in a Typical Carya cathayensis Production Area].

In recent years, the problem of soil pollution has become more and more serious. The problem of soil heavy metal pollution and its related human health risks has become a hot spot at home and abroad. Carya cathayensis is a unique high-grade woody nut and oil tree from China, and there are few reports on heavy metal pollution in Carya cathayensis plantation soils. Therefore, in order to study the spatial variability of heavy metals and the risk of pollution in Carya cathayensis soil and to promote the sustainable development of the Carya cathayensis industry, Lin'an, a typical Carya cathayensis plantation area, was selected for this study. A total of 188 soil samples were collected from the study area. We systematically studied the spatial heterogeneity of soil heavy metal content in the study area based on GIS technology, geostatistics, Moran's I, and other spatial analysis methods. The single factor pollution index method, the Nemerow comprehensive pollution index method, and the potential ecological risk assessment method were used to evaluate the heavy metal pollution in the study area. The results indicated that the mean content of soil cadmium (Cd), copper (Cu), zinc (Zn), lead (Pb), nickel (Ni), and chromium (Cr) were 0.37, 40.76, 87.61, 30.10, 28.33, 56.57 mg·kg-1, respectively. The average values of Cd and Cu were 1.33 and 2.87 times of the background values, respectively, and the average content of other heavy metals did not exceed the background values. The results of the single factor Nemerow pollution index and potential ecological risk assessment methods showed that heavy metals in the study area exceeded the soil background values in some samples, and the second grade standard of soil environmental quality was exceed for Cd, Cu, Zn, Pb, and Ni in 31.38%, 31.38%, 2.65%, 0.53%, and 17.02% of the samples, respectively. This indicated that the soils in the study area had different accumulation characteristics for Cd, Cu, Zn, Pb, Ni, and Cr, and the local soil had reached pollution levels for Cd, Cu, Zn, Pb, and Ni. Among them, Cd was the most serious, reaching the degree of strong ecological damage, followed by Cu. In general, the heavy metal contents indicated a moderate degree of ecological damage. Based on the analysis of the semi-variance function, the Cd, Cu, and Ni in the soil were best fit with exponential models, the Zn and Pb were better fit with the Gaussian model, and Cr was consistent with the spherical model. Cd, Cu, Pb, Ni, and Cr had the strong spatial autocorrelation, with Nugget/Sill ratios of 12.1%, 4.6%, 14.9%, 2.6%, and 11.2%, respectively, while the Nugget/Sill ratio of Zn was 48.8%, indicating a medium spatial autocorrelation. Moran's I and Kriging interpolation results found that the heavy metals Cd, Cu, Zn, Pb, Ni, and Cr all had obvious spatial distribution patterns and local spatial aggregation phenomena. The high values of heavy metals in soils were mainly found in Taiyang, Daoshi, Qingliangfeng, Heqiao, and Tuankou, and the probability of the risk for contamination by Cd and Cu was higher in the study area. The high values of Cd, Cu, Zn, Ni, and Cr were mainly related to mining, while Pb was closely related to the application of potassium.

[Inhibitory effect of silencing STAT3 gene with short hairpin RNA mediated by polyamidoamine dendrimers on growth of prostate cancer].

OBJECTIVE: To investigate the possibility of using generation 5 polyamidoamine dendrimers (G5-PAMAM-D) as gene vector for eukaryotic expression plasmid of siRNA in prostate carcinoma in vitro and vivo. METHODS: Firstly, eukaryotic expression vector of siRNA pSilencing 4.1-EGFP-shRNA, specific for enhanced green fluorescent protein (EGFP), pSilencing 4.1-STAT3-shRNA for signal transducers and activators of transcription 3 (STAT3) was constructed. pEGFP-C1 and pSilencing 4.1-EGFP-shRNA were cotransfected into prostate cancer cells PC-3 and 22Rv1 with G5-PAPAM-D as vector, and to observe silencing of EGFP. Next, pSilencing 4.1-STAT3-shRNA was transfected into PC-3 and 22Rv1 cells by G5-PAPAM-D, Western blotting and apoptosis staining was used to detect silencing of STAT3 and growth inhibition. Thirdly, BALB/C mice subcutaneous tumor model was made with PC-3 cells. Polyplex of G5-PAMAM-D and pSilencing 4.1-STAT3-shRNA was injected intratumorally. The tumor volume was measured and recorded. RESULTS: Fluorescence detection and Western blotting analysis demonstrated that G5-PAMAM-D was able to deliver Silencing 4.1-EGFP-shRNA and pSilencing 4.1-STAT3-shRNA into the two prostate cancer cell lines, and shRNA was expressed to induce silence of EGFP and STAT3. MTT results showed that proliferation of prostate cancer cells was suppressed by G5-PAMAM-D/pSilencing 4.1-STAT3-shRNA and induced apoptosis of PC-3 cells in vitro. Human prostate cancer in mice was successfully formed by inoculation of PC-3 cells into male BABL/C mice. In G5-PAMAM-D/pSilencing 4.1-STAT3-shRNA treated group, the tumor volume was shrank remarkably at 9 days after treatment and tumor growth was retarded compared with control groups. CONCLUSION: GS-PAMAM-D nanoparticles can be used to deliver plasmid vector expressing shRNA into prostate cancer cells effectively in vitro and vivo. It appears to be a promising gene vector for RNA interference therapy in prostate cancer.

Ganoderic acid T from Ganoderma lucidum mycelia induces mitochondria mediated apoptosis in lung cancer cells.

Ganoderma lucidum is a well-known traditional Chinese medicinal herb containing many bioactive compounds. Ganoderic acid T (GA-T), which is a lanostane triterpenoid purified from methanol extract of G. lucidum mycelia, was found to exert cytotoxicity on various human carcinoma cell lines in a dose-dependent manner, while it was less toxic to normal human cell lines. Animal experiments in vivo also showed that GA-T suppressed the growth of human solid tumor in athymic mice. It markedly inhibited the proliferation of a highly metastatic lung cancer cell line (95-D) by apoptosis induction and cell cycle arrest at G(1) phase. Moreover, reduction of mitochondria membrane potential (Delta psi(m)) and release of cytochrome c were observed during the induced apoptosis. Our data further indicate that the expression of proteins p53 and Bax in 95-D cells was increased in a time-dependent manner, whereas the expression of Bcl-2 was not significantly changed; thus the ratio of Bcl-2/Bax was decreased. The results show that the apoptosis induction of GA-T was mediated by mitochondrial dysfunctions. Furthermore, stimulation of the activity of caspase-3 but not caspase-8 was observed during apoptosis. The experiments using inhibitors of caspases (Z-VAD-FMK, Z-DEVD-FMK and Z-IETD-FMK) confirmed that caspase-3 was involved in the apoptosis. All our findings demonstrate that GA-T induced apoptosis of metastatic lung tumor cells through intrinsic pathway related to mitochondrial dysfunction and p53 expression, and it may be a potentially useful chemotherapeutic agent.

tRNASer(CGA) differentially regulates expression of wild-type and codon-modified papillomavirus L1 genes.

Exogenous transfer RNAs (tRNAs) favor translation of bovine papillomavirus 1 wild-type (wt) L1 mRNA in in vitro translation systems (Zhou et al. 1999, J. Virol., 73, 4972-4982). We, therefore, investigated whether papillomavirus (PV) wt L1 protein expression could be enhanced in eukaryotic cells following exogenous tRNA supplementation. Both Chinese hamster ovary (CHO) and Cos1 cells, transfected with PV1 wt L1 genes, effectively transcribed the genes but did not translate them. However, L1 protein translation was demonstrated following co-transfection with the L1 gene and a gene expressing tRNA(Ser)(CGA). Cell lines, stably transfected with a bovine papillomavirus 1 (BPV1) wt L1 expression construct, produced L1 protein after the transfection of the tRNA(Ser)(CGA) gene, but not following the transfection with basal vectors, suggesting that tRNA(Ser)(CGA) gene enhanced wt L1 translation as a result of endogenous tRNA alterations and phosphorylation of translation initiation factors elF4E and elF2alpha in the tRNA(Ser)(CGA) transfected L1 cell lines. The tRNA(Ser)(CGA) gene expression significantly reduced translation of L1 proteins expressed from codon-modified (HB) PV L1 genes utilizing mammalian preferred codons, but had variable effects on translation of green fluorescent proteins (GFPs) expressed from six serine GFP variants. The changes of tRNA pools appear to match the codon composition of PV wt and HB L1 genes and serine GFP variants to regulate translation of their mRNAs. These findings demonstrate for the first time in eukaryotic cells that translation of the target genes can be differentially influenced by the provision of a single tRNA expression construct.