Aptamer-Based Multiparameter Analysis for Molecular Profiling of Hematological Malignancies

The subtypes of hematological malignancies (HM) with minimal molecular profile differences display an extremely heterogeneous clinical course and a discrepant response to certain treatment regimens. Profiling the surface protein markers offers a potent solution for precision diagnosis of HM by differentiating among the subtypes of cancer cells. Herein, we report the use of Cell-SELEX technology to generate a panel of high-affinity aptamer probes that are able to discriminate subtle differences among surface protein profiles between different HM cells. Experimental results show that these aptamers with apparent dissociation constants (Kd) below 10 nM display a unique recognition pattern on different HM subtypes. By combining a machine learning model on the basis of partial least-squares discriminant analysis, 100% accuracy was achieved for the classification of different HM cells. Furthermore, we preliminarily validated the effectiveness of the aptamer-based multiparameter analysis strategy from a clinical perspective by accurately classifying complex clinical samples, thus providing a promising molecular tool for precise HM phenotyping.

Dietary supplementation of proteases on growth performance, nutrient digestibility, blood characteristics and gut microbiota of growing pigs fed sorghum-based diets

Low-tannin sorghum is an excellent energy source in pig diets. However, sorghum contains several anti-nutritional factors that may have negative effects on nutrient digestibility. The impacts of proteases on growth performance, nutrient digestibility, blood parameters, and gut microbiota of growing pigs fed sorghum-based diets were studied in this study. Ninety-six pigs (20.66 ± 0.65 kg BW) were allocated into three groups (eight pens/group, four pigs/pen): (1) CON (control diet, sorghum-based diet included 66.98% sorghum), (2) PRO1 (CON + 200 mg/kg proteases), (3) PRO2 (CON + 400 mg/kg proteases) for 28 d. No differences were observed in growth performance and apparent total tract digestibility (ATTD) of nutrients between CON and PRO1 groups. Pigs fed PRO2 diet had increased (P < 0.05) BW on d 21 and 28, and increased (P < 0.05) average daily gain during d 14-21 and the overall period compared with pigs fed CON diet. In addition, pigs fed PRO2 diet had improved (P < 0.05) ATTD of gross energy, CP, and DM compared with pigs fed CON and PRO1 diets. Pigs fed PRO2 diet had lower (P < 0.05) plasma globulin (GLB) level and higher (P < 0.05) plasma glucose, albumin (ALB) and immunoglobulin G levels, and ALB/GLB ratio than pigs fed CON and PRO1 diets. Furthermore, pigs fed PRO2 diet had decreased (P < 0.05) the relative abundance of Acidobacteriota at the phylum level and increased (P < 0.05) the relative abundance of Prevotella_9 at the genus level. The linear discriminant analysis effect size analysis also showed that pigs fed PRO2 diet had significantly enriched short-chain fatty acid-producing bacteria, such as Subdoligranulum and Parabacteroides. In conclusion, protease supplementation at 400 mg/kg improved the growth performance of growing pigs fed sorghum-based diets, which may be attributed to the improvement of nutrient digestibility, host metabolism, immune status and associated with the altered gut microbiota profiles.

Effects of dietary methionine supplementation from different sources on growth performance and meat quality of barrows and gilts

Methionine is indispensable for growth and meat formation in pigs. However, it is still unclear that increasing dietary sulphur-containing amino acid (SAA) levels using different methionine sources affects the growth performance and meat quality of barrows and gilts. To investigate this, 144 pigs (half barrows and half gilts) were fed the control (100% SAA, CON), DL-Methionine (125% SAA, DL-Met)-supplemented, or OH-Methionine (125% SAA, OH-Met)-supplemented diets during the 11-110 kg period. The results showed that plasma methionine levels varied among treatments during the experimental phase, with increased plasma methionine levels observed following increased SAA consumption during the 25-45 kg period. In contrast, pigs fed the DL-Met diet had lower plasma methionine levels than those fed the CON diet (95-110 kg). Additionally, gilts fed the DL-Met or OH-Met diets showed decreased drip loss in longissimus lumborum muscle (LM) compared to CON-fed gilts. OH-Met-fed gilts had higher pH45min values than those fed the CON or DL-Met diets, whereas OH-Met-fed barrows had higher L45min values than those fed the CON or DL-Met diets. Moreover, increased consumption of SAA, regardless of the methionine source, tended to decrease the shear force of the LM in pigs. In conclusion, this study indicates that increasing dietary levels of SAA (+25%) appeared to improve the meat quality of gilts by decreasing drip loss and increasing meat tenderness.

An Aptamer-Functionalized DNA Circuit to Establish an Artificial Interaction between T Cells and Cancer Cells

Nongenetic strategies that enable control over the cell-cell interaction network would be highly desired, particularly in T cell-based cancer immunotherapy. In this work, we developed an aptamer-functionalized DNA circuit to modulate the interaction between T cells and cancer cells. This DNA circuit was composed of recognition-then-triggering and aggregation-then-activation modules. Upon recognizing target cancer cells, the triggering strand was released to induce aggregation of immune receptors on the T cell surface, leading to an enhancement of T cell activity for effective cancer eradication. Our results demonstrated the feasibility of this DNA circuit for promoting target cancer cell-directed stimulation of T cells, which, consequently, enhanced their killing effect on cancer cells. This DNA circuit, as a modular strategy to modulate intercellular interactions, could lead to a new paradigm for the development of nongenetic T cell-based immunotherapy.

Aptamer-based expansion microscopy platform enables signal-amplified imaging of dendritic spines

Super-resolution imaging of dendritic spines (DS) can provide valuable information for mechanistic studies related to synaptic physiology and neural plasticity, but challenged by their small dimension (50-200 nm) below the spatial resolution of conventional optical microscopes. In this work, by combining the molecular recognition specificity of aptamer with high programmability of DNA nanotechnology, we developed an expansion microscopy (ExM) platform for imaging DS with enhanced spatial resolution and amplified signal output. Our results demonstrated that the aptamer probe could specifically bind to DS of primary hippocampal neurons. With physical expansion, the DS structure could be effectively enlarged by 4-5 folds, leading to the generation of more structural information. Meantime, the aptamer binding signal could be readily amplified by the introduction of DNA signal amplification strategy, overcoming the drawback of fluorescence dilution during the ExM treatment. This platform enabled evaluation of ischemia-induced early stroke based on the morphological change of DS, highlighting a promising avenue for studying nanoscale structures in biological systems.

Sodium MRI at 7T for Early Response Evaluation of Intracranial Tumors following Stereotactic Radiotherapy Using the CyberKnife

BACKGROUND AND PURPOSE

Conventionally, early treatment response to stereotactic radiotherapy in intracranial tumors is often determined by structural MR imaging. Tissue sodium concentration is altered by cellular integrity and energy status in cells. In this study, we aimed to investigate the feasibility of sodium MR imaging at 7T for the preliminary evaluation of radiotherapeutic efficacy for intracranial tumors.

MATERIALS AND METHODS

Data were collected from 16 patients (12 men and 4 women, 24-75 years of age) with 22 intracranial tumors who were treated with stereotactic radiation therapy using CyberKnife at our institution between December 1, 2016, and August 15, 2019. Sodium MR imaging was performed at 7T before and 48 hours, 1 week, and 1 month after CyberKnife radiation therapy. Tissue sodium concentration (TSC) was calculated and analyzed based on manually labeled regions of tumors.

RESULTS

Ultra-high-field sodium MR imaging clearly showed the intratumoral signal, which is significantly higher than that of normal tissue (t = 5.250, P <.001)., but the edema zone has some influence. The average TSC ratios of tumor to CSF in the 22 tumors, contralateral normal tissues, edema zones, frontal cortex, and frontal white matter were 0.66 (range, 0.23-1.5), 0.30 (range, 0.15-0.43), 0.58 (range, 0.25-1.21), 0.25 (range, 0.17-0.42), and 0.30 (range, 0.19-0.49), respectively. A total of 12 tumors in 8 patients were scanned at 48 hours, 1 week, and 1 month after treatment. The average TSC at 48 hours after treatment was 0.06 higher than that before treatment and began to decrease at 1 week. The TSC ratios of 10 continued to decline and 2 tumors increased at 1 month, respectively. Tumor volume decreased by 2.4%-99% after 3 months.

CONCLUSIONS

Changes in the TSC can be quantified by sodium MR imaging at 7T and used to detect radiobiologic alterations in intracranial tumors at early time points after CyberKnife radiation therapy.

Rubidium chloride modulated the fecal microbiota community in mice

Background

The microbiota plays an important role in host health. Although rubidium (Rb) has been used to study its effects on depression and cancers, the interaction between microbial commensals and Rb is still unexplored. To gain the knowledge of the relationship between Rb and microbes, 51 mice receiving RbCl-based treatment and 13 untreated mice were evaluated for their characteristics and bacterial microbiome changes.

Results

The 16S ribosomal RNA gene sequencing of fecal microbiota showed that RbCl generally maintained fecal microbial community diversity, while the shifts in fecal microbial composition were apparent after RbCl exposure. RbCl significantly enhanced the abundances of Rikenellaceae, Alistipes, Clostridium XlVa and sulfate-reducing bacteria including Deltaproteobacteria, Desulfovibrionales, Desulfovibrionaceae and Desulfovibrio, but significantly inhibited the abundances of Tenericutes, Mollicutes, Anaeroplasmatales, Anaeroplasmataceae and Anaeroplasma lineages. With regarding to the archaea, we only observed two less richness archaea Sulfolobus and Acidiplasma at the genus level.

Conclusions

Changes of fecal microbes may in part contribute to the anticancer or anti-depressant effects of RbCl. These findings further validate that the microbiome could be a target for therapeutic intervention.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-021-02095-4.

Functional Nucleic Acid-Based Live-Cell Fluorescence Imaging

Cell is the structural and functional unit of organism. It serves as a key research object in various biological processes, such as growth, ontogeny, metabolism and stress. Studying the spatiotemporal distribution and functional activity of specific biological molecules in living cells is crucial for exploring the mechanism governing life. It also facilitates the elucidation of pathogenesis, clinical prevention and disease theranostics. In recent years, the fluorescence imaging technique has been greatly exploited for live-cell imaging. However, the development of molecular probes has lagged far behind. Functional nucleic acids (FNAs), for example, aptamer and DNAzyme, possess special chemical and/or biological functions, hence severing as promising molecular tools for cellular imaging. The current mini review focuses on the applications of FNAs in live-cell fluorescence imaging.

Nanoscale diffusive memristor crossbars as physical unclonable functions

Physical unclonable functions have emerged as promising hardware security primitives for device authentication and key generation in the era of the Internet of Things. Herein, we report novel physical unclonable functions built upon the crossbars of nanoscale diffusive memristors that translate the stochastic distribution of Ag clusters in a SiO₂ matrix into a random binary bitmap that serves as a device fingerprint. The random dispersion of Ag led to an uneven number of clusters at each cross-point, which in turn resulted in a stochastic ability to switch in the Ag:SiO₂ diffusive memristors in an array. The randomness of the dispersion was a barrier to fingerprint cloning and the unique fingerprints of each device were persistent after fabrication. Using an optimized fabrication procedure, we maximized the randomness and achieved an inter-class Hamming distance of 50.68%. We also discovered that the bits were not flipping after over 10⁴ s at 400 K, suggesting superior reliability of our physical unclonable functions. In addition, our diffusive memristor-based physical unclonable functions were easy to fabricate and did not require complicated post-processing for digitization and thus, provide new opportunities in hardware security applications.

Decreased Expression of MYPT1 Contributes to Tumor Angiogenesis and Poor Patient Prognosis in Human Prostate Cancer

BACKGROUND

Our previous study demonstrated that Myosin Phosphatase Targeting subunit 1 (MYPT1) may function as a direct target of microRNA-30d, which promotes tumor angiogenesis and tumor growth of prostate cancer (PCa). Here, we aimed to investigate the clinical significance of MYPT1 expression and its functions in PCa.

METHODS

Roles of MYPT1 deregulation in tumor angiogenesis of PCa was determined in vitro and in vivo experiments. Expression patterns of MYPT1 and CD31 proteins were examined by immunohistochemistry and immunofluorescence, respectively. Associations of MYPT1/CD31 combination with various clinicopathological features and patients' prognosis of PCa were also statistically evaluated.

RESULTS

Through gain- and loss-of-function experiments, MYPT1 inhibited capillary tube formation of endothelial cells and in vivo tumor angiogenesis in a mouse model with the downregulation of VEGF and CD31 expression. In addition, MYPT1 expression was significantly decreased, while CD31 expression was dramatically increased in PCa tissues compared to benign prostate tissues. Notably, MYPT1 expression levels in PCa tissues were negatively correlated with that of CD31. Statistically, MYPT1-low/CD31- high expression was distinctly associated with high Gleason score, positive biochemical recurrence, and reduced overall survival of PCa patients. Moreover, PCa patients with MYPT1-low/CD31-high expression more frequently had shorter overall, biochemical recurrence-free and metastasis-free survivals. MYPT1/CD31 combination was identified as an independent factor to predict biochemical recurrence-free and metastasis-free survivals of PCa patients.

CONCLUSIONS

Our findings indicate that MYPT1 may inhibit angiogenesis and contribute favorable prognosis in PCa patients, implying that MYPT1 might be a potential drug candidate in anticancer therapy.

Perdeuterated and 13C-enriched myo-inositol for DNP assisted monitoring of enzymatic phosphorylation by inositol-3-kinase

The synthesis of perdeuterated and 13C enriched myo-inositol is presented. Myo-inositol and its derivatives are of interest as substrates for enzymes producing phosphorylated species with regulatory functions in many organisms. Its utility in monitoring real-time phosphorylation by myo-inositol-3-kinase is illustrated using dynamic nuclear polarization (DNP) to enhance NMR observation.

Mechanism of pingyangmycin-induced apoptosis of cultured human umbilical vein endothelial cells

In this study, we investigated the effects of pingyangmycin (PYM) on the growth inhibition and apoptosis of human umbilical vein endothelial cells (HUVEC). In this study, we aimed to explore the optimal concentration of PYM to induce the apoptosis of HUVEC and to determine its mechanism of action. After treatment of HUVEC with different concentrations of PYM for 24 h, cell counting kit-8 (CCK-8) was used to detect growth inhibiting effects. Annexin V-FITC/propidium iodide stain was used to detect apoptosis, and western blot was used to detect the expression of glucose-related protein 78 (GPR78) and C/EBP homologous protein (CHOP) endoplasmic reticulum stress proteins. With increasing PYM concentration, the growth inhibition of HUVEC increased (P < 0.05), the apoptotic numbers of HUVEC increased (P < 0.05), with higher PYM concentrations inducing necrosis, and the protein expression of GRP78 and CHOP increased (P < 0.05). PYM could obviously inhibit the proliferation and promote the apoptosis of HUVEC. Necrotic cells were more prevalent than apoptotic cells at high PYM concentrations. This study helped to determine the proper concentration of PYM to induce more apoptosis than necrosis, which is critical to minimize inflammation, enhance the healing of the skin, and maintain safety for the patient. PYM might induce HUVEC apoptosis through the endoplasmic reticulum stress pathway.

Identification and pathogenicity of Vibrio parahaemolyticus isolates and immune responses of Penaeus (Litopenaeus) vannamei (Boone)

Five different Vibrio parahaemolyticus strains (SH8, SH108, SH58, AH5 and GD10) isolated from the hepatopancreas of moribund shrimp in farms of mainland China were identified and capable of inducing massive mortality of Penaeus (Litopenaeus) vannamei. The immersion challenge results with five isolates indicated variance of virulence, while only GD10 caused massive sloughing of tubule epithelial cells which was recognized as the most significant symptom of AHPND. Differences in immune responses were detected of P. vannamei during 48 h post-infection (p.i.) by injection or immersion challenge with V. parahaemolyticus (SH8, SH108 and GD10) isolates. When injected SH8 and SH108 isolates, the expression of lysozyme (LSZ) showing statistically significant upregulation at 16 and 48 h p.i. and that of Toll-like receptors (TLR) showed statistically significant upregulation at 48 h p.i. When immersion challenge with the GD10 isolate, TLR were upregulated after 8 h p.i. challenge with 10(4)  cfu mL(-1) ; however, LSZ was downregulated when challenged with 10(3)  cfu mL(-1) . The results suggested that LSZ and TLR serve as crucial molecular markers of innate immunity in shrimp against V. parahaemolyticus infection. LSZ is a vital marker for acute bacterial infection, while TLR serves as a crucial marker for chronic infection.

A novel aptasensor for thrombin detection based on alkaline phosphatase decorated ZnO/Pt nanoflowers as signal amplifiers

To remedy the problems caused by the introduction of an additional electron mediator and realize signal amplification, a new strategy has been presented to construct an electrochemical aptasensor for thrombin detection based on the cascade electrocatalysis of alkaline phosphatase (ALP) and Pt nanoparticle (PtNP)-functionalized ZnO nanoflowers.

Effects of long term treatment with high doses of odanacatib on bone mass, bone strength, and remodeling/modeling in newly ovariectomized monkeys

The objectives here were to evaluate the effects of odanacatib (ODN) at doses exceeding the clinical exposure on biomechanical properties of lumbar vertebrae (LV), hip and central femur (CF), and compare ODN to alendronate (ALN) on bone remodeling/modeling in ovariectomized (OVX) monkeys. Ten days post-surgery, animals were treated with vehicle (VEH), ODN-L (2mg/kg/day, p.o.), ODN-H (8/4mg/kg/day), or ALN (30μg/kg/week, s.c.) for 20months. An intact group was also included. ODN-L provided systemic exposures of 1.8-fold of clinical exposure. ODN-H started at 20-fold for 5.5months, and then reduced to 7.8-fold of clinical exposure, compared to ALN at approximated clinical exposure. From cross sectional analyses, LV density and peak load in ODN at both doses or ALN were not different from VEH or Intact. However, cortical thickness of femoral neck (FN) and CF in ODN were higher (21-34%, p<0.05) than VEH, due to smaller endocortical (Ec) perimeter of FN (10-11%; p<0.05) and CF (9-12%; ODN-L, p<0.05), and larger CF periosteal (Ps) perimeter (2-12%; ODN-H, p<0.001) versus VEH. ODN groups also showed slightly higher cortical porosity and Ps non-lamellar bone in CF. ODN-H treatment resulted in higher CF peak load (p<0.05) versus VEH. For all bone sites analyzed, a positive, linear relationship (r(2)=0.46-0.69, p<0.0001) of peak load to density or structural parameters was demonstrated. No treatment-related differences in the derived intrinsic strength properties were evidenced as compared between groups. ALN reduced all remodeling surfaces without affecting Ps modeling. Trabecular and intracortical remodeling were reduced in ODN groups, similar to ALN. Ec mineralizing surface in ODN-H trended to be lower than VEH by month 20, but Ec bone formation indices in ODN groups generally were not different from VEH. Ps modeling in ODN groups was significantly higher than other treatment groups. This study overall demonstrated the bone safety profile of ODN and its unique mechanism on cortical bone supporting the clinical application for osteoporosis treatment.

Recent advances in engineering nonribosomal peptide assembly lines

Nonribosomal peptides are amongst the most widespread and structurally diverse secondary metabolites in nature with many possessing bioactivity that can be exploited for therapeutic applications. Due to the major challenges associated with total- and semi-synthesis, bioengineering approaches have been developed to increase yields and generate modified peptides with improved physicochemical properties or altered bioactivity. Here we review the major advances that have been made over the last decade in engineering the biosynthesis of nonribosomal peptides. Structural diversity has been introduced by the modification of enzymes required for the supply of precursors or by heterologous expression of tailoring enzymes. The modularity of nonribosomal peptide synthetase (NRPS) assembly lines further supports module or domain swapping methodologies to achieve changes in the amino acid sequence of nonribosomal peptides. We also review the new synthetic biology technologies promising to speed up the process, enabling the creation and optimisation of many more assembly lines for heterologous expression, offering new opportunities for engineering the biosynthesis of novel nonribosomal peptides.

Recent Advances in Biosensing With Photonic Crystal Surfaces: A Review

Photonic crystal surfaces that are designed to function as wavelength-selective optical resonators have become a widely adopted platform for label-free biosensing, and for enhancement of the output of photon-emitting tags used throughout life science research and in vitro diagnostics. While some applications, such as analysis of drug-protein interactions, require extremely high resolution and the ability to accurately correct for measurement artifacts, others require sensitivity that is high enough for detection of disease biomarkers in serum with concentrations less than 1 pg/ml. As the analysis of cells becomes increasingly important for studying the behavior of stem cells, cancer cells, and biofilms under a variety of conditions, approaches that enable high resolution imaging of live cells without cytotoxic stains or photobleachable fluorescent dyes are providing new tools to biologists who seek to observe individual cells over extended time periods. This paper will review several recent advances in photonic crystal biosensor detection instrumentation and device structures that are being applied towards direct detection of small molecules in the context of high throughput drug screening, photonic crystal fluorescence enhancement as utilized for high sensitivity multiplexed cancer biomarker detection, and label-free high resolution imaging of cells and individual nanoparticles as a new tool for life science research and single-molecule diagnostics.

Conservation and population genetic diversity of Curcuma wenyujin (Zingiberaceae), a multifunctional medicinal herb

Curcuma wenyujin is an important multifunctional medicinal herb in China. Currently, populations of C. wenyujin are decreasing, and wild individuals have almost disappeared from their natural habitats. Moreover, little is known regarding the molecular characteristics of this plant. In this study, we investigated the genetic diversity and variation of five populations of C. wenyujin, using ran-dom amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers. We found that the percentages of polymorphic loci (PPL) at the species level (98.25% by RAPD and 100% by ISSR) were significantly higher than those at the population level (66.32% by RAPD and 67.14% by ISSR). The highest values of PPL, expected heterozygosity, and Shannon's information index were in Pop1, while the lowest values were in Pop2. Both DNA markers revealed a short genetic distance between Pop1 and Pop2 (0.1424 by RAPD and 0.1904 by ISSR). Phylogenetic trees produced similar results, with Pop1, Pop2, and Pop5 in one group and Pop3 and Pop4 in another. There were no significant correlations between their genetic distances and their geographical distances. The highest genetic diversity was in Pop1 and the lowest was in Pop2, and genetic diversity at the species level was relatively low, but much higher than that at the population level. We recommended the establishment of a germplasm bank, in situ con-servation, and propagation of wild individuals. The present study will improve the evaluation, protection, and utilization of the population resources of C. wenyujin.

Immune memory responses to HBV vaccine 13-18 years after primary vaccination

The aim of this study was to evaluate the immune memory response 13-18 years after an hepatitis B virus (HBV) vaccine by performing a specific in vitro stimulation experiment. Thirty healthy volunteers who had been inoculated 13-18 years ago with the HBV vaccine were collected from the physical examination center. Peripheral blood mononuclear cells were stimulated with 50 ng/mL recombinant HBsAg. An ELISA kit was used for the detection of antibodies that were produced by these cells in vitro. It was found that even 13-18 years after inoculation with the HBV vaccine, an anamnestic antibody response still existed, and was not correlated with the serum antibody levels (r = -0.177, P = 0.377). In conclusion, our data showed that the individuals after inoculation, including those with anti-HBs <10 IU/L as well as those individuals in whom the antibody was not detected, retained immune memory, which may be the main role of memory B cells.

Inhibition of bone resorption by the cathepsin K inhibitor odanacatib is fully reversible

The cathepsin K (CatK) inhibitor odanacatib (ODN) is currently being developed for the treatment of osteoporosis. In clinical trials, efficacy and resolution of effect of ODN treatment on bone turnover biomarkers and accrued bone mass have been demonstrated. Here, we examine the effects of continuing treatment and discontinuation of ODN versus alendronate (ALN) on osteoclast (OC) function. First, accessibility and reversible engagement of active CatK in intracellular vesicles and resorption lacunae of actively resorbing OCs were demonstrated by the selective and reversible CatK inhibitors, BODIPY-L-226 (IC50=39nM) and L-873,724 (IC50=0.5nM). Next, mature human OCs on bone slices were treated with vehicle, ODN, or ALN for 2days, followed by either continuing with the same treatment, or replacement of the inhibitors by vehicle for additional times as specified per experimental conditions. Maintaining OCs on ODN or ALN significantly reduced CTx-I release compared to vehicle controls. However, only the treatment of OCs with ODN resulted in the formation of small shallow discrete resorption pits, retention of intracellular vesicles enriched with CatK and other lysosomal enzymes, increase in 1-CTP release and number of TRAP(+) OCs. Upon discontinuation of ODN treatment, OCs rapidly resumed bone resorption activity, as demonstrated by a return of OC functional markers (CTx-I, 1-CTP), cell number and size, morphology and number of resorption pits, and vesicular secretion of CatK toward the respective vehicle levels. As expected, discontinuation of ALN did not reverse the treatment-related inhibition of OC activity in the time frame of the experiment. In summary, this study demonstrated rapid kinetics of inhibition and reversibility of the effects of ODN on OC bone resorption, that differentiated the cellular mechanism of CatK inhibition from that of the bisphosphate antiresorptive ALN.

Nuclear factor erythroid 2-related factor 2 rescues the oxidative stress induced by di-N-butylphthalate in testicular Leydig cells

Aim:

This study aimed to determine whether nuclear factor erythroid 2-related factor 2 antagonized the oxidative stress induced by di- N-butylphthalate (DBP) in testicular Leydig cells.

Methods:

Mouse TM3 testicular Leydig cells were treated with Nrf2 knockdown (KD) or overexpression in the presence and absence of DBP. Oxidative profiles were examined. Nrf2 target antioxidant genes were studied, and the effects of Nrf2 inducer sulphoraphane (SFN) were tested.

Results:

DBP induced intracellular oxidative stress to a similar extent with Nrf2 KD. Expression and protein levels of Nrf2 were increased together with its target genes, namely heme oxygenase 1, nicotinamide adenine dinucleotide phosphate quinone oxidoreductase 1 and peroxiredoxin 6, following DBP stimulation. Use of SFN not only restored the intracellular oxidative toxicity but also cell proliferation and testosterone secretion in response to DBP.

Conclusion:

Increased Nrf2 activity, for example, by SFN can effectively antagonize the oxidative stress in testicular Leydig cells caused by DBP.

The effects of the cathepsin K inhibitor odanacatib on osteoclastic bone resorption and vesicular trafficking

Odanacatib (ODN) is a selective, potent and reversible inhibitor of cathepsin K (CatK) that inhibits bone loss in postmenopausal osteoporosis. Evidence from osteoclast (OC) formation from bone marrow of CatK(-/-) mice or human OC progenitors treated with ODN, demonstrated that CatK inhibition has no effect on osteoclastogenesis or survival of OCs. Although having no impact on OC activation, ODN reduces resorption activity as measured by CTx release (IC(50)=9.4 nM) or resorption area (IC(50)=6.5 nM). While untreated cells generate deep trail-like resorption lacunae, treated OCs form small discrete shallow pits. ODN leads to significant accumulation of intracellular vesicles intensely stained for CatK and TRAP. CatK (+) vesicles localize toward the basolateral and functional secretory membranes of the polarized OC and TRAP(+) vesicles evenly distribute in the cytoplasm, suggesting that ODN disrupts multiple vesicular trafficking pathways. Intracellular levels of both precursor and mature TRAP were increased by 2-fold and the pre-pro and mature CatK by 6- and 2-fold in ODN-treated OCs compared to untreated controls. ODN treated OC accumulates labeled degraded bone matrix proteins in CatK containing vesicles. In summary, ODN treatment inhibits bone resorption by blocking degradation of demineralized collagen in the resorption lacunae, and retarding transcytosis for further processing of degraded proteins.

Construction of the enhanced yellow fluorescent protein expression vector carrying IFN-gamma gene

PURPOSE

To construct the enhanced yellow fluorescent protein (EYFP) vector carrying interferon-gamma gene (ifn-gamma) in order to provide an ideal reporter in the expression of ifn-gamma and location of protein in vitro and in vivo.

METHOD

According to the nucleotide sequence of ifn-gamma gene, a pair of oligonucleotides was designed as primer whose two end contained nucleotide sequence of EcoR V and Not I restriction endonuclease respectively. The gene encoding for inf-gamma was amplified using PCR technqiue. After the PCR product was retrieved and purified, it was digested with EcoR V and Not I restriction endonuclease, and then cloned into the plasmid pIRES-EYFP. The recombinant plasmid pIRES-EYFPIFN-gamma was identified by restriction endonuclease enzyme analysis and DNA sequence analysis.

RESULTS

The ifn-gamma was successfully amplified and verified by partial DNA sequence analysis. The recombinant plasmid was correctly screened.

CONCLUSION

The EYFP expression vector carrying ifn-gamma gene was successfully established. This research work has formed a base for monitoring the ifn-gamma gene expression and protein position in living cells.

Identified circadian rhythm genes of ciliary epithelium with differential display

PURPOSE

To identify differential genes expressed in the rabbit ciliary epithelium during the circadian cycle of aqueous flow.

METHODS

Total RNA from ciliary epithelium of rabbits at 8 AM (light on 1 hour) and 8 PM (light off 1 hour) were compared by differential display reverse transcription-polymerase chain reaction (DD RT-PCR), using 6% denaturing polyacrylamide electrophoresis, choose differential display bands, cut and reamplify with the same primer, clone and sequence. Search the database of Genbank, prolong them with 5' RACE and 3' RACE technique then clone, sequence and search database of Genbank.

RESULTS

93 Significant differences gene expression were detected between light on and light off in the rabbit ciliary epithelium.

CONCLUSION

Differential display is a powerful tool to screen differentially expressed genes in circadian rhythm of ciliary epithelium.

[Phacoemulsification in patients with cataract and overfiltering bleb after antiglaucoma surgery]

PURPOSE

To evaluate the effect of phacoemulsification in patients with cataract, overfiltering bleb, and low-tension after antiglaucoma surgery.

METHODS

Phacoemulsification and implantation of a foldable intraocular len was performed in six patients(7 eyes) with overfiltering bleb, low-tension, and cataract. The complications, blebs, intraocular pressures(IOP), and visual acuity were observed postoperatively.

RESULTS

No severe complication was found. The overfiltering blebs constricted and their walls became thicker three months after the operation. The visual acuity and IOP were improved (P < 0.05).

CONCLUSION

Phacoemulsification may be another way to treat the patients with cataract and overfiltering bleb, low-tension after antiglaucoma surgery.

The attentional effects of peripheral cueing as revealed by two event-related potential studies

OBJECTIVE

The mechanism of visual spatial attention elicited by peripheral cueing was investigated in two studies.

METHOD

Event-related potentials (ERPs) were recorded when the subjects were performing a spatial frequency discrimination task and a location discrimination task. Stimuli were randomly flashed in the left or right visual field. Prior to each stimulus a peripheral cue was presented with a validity of 75%.

RESULTS

The subjects responded faster to valid trials than to invalid trials. The earliest visual ERP component, C1, was not modulated by the cue validity, suggesting that visual spatial attention elicited by peripheral cueing does not involve striate cortex. Valid trials elicited larger contralateral P1 but a smaller contralateral N1 than invalid trials. The early onsets of these attentional effects show that spatial attention affects stimulus processing at early sensory/perceptual stages. The latencies of contralateral P1 and contralateral N1 were shorter for invalid trials, however. The ipsilateral N1 was enhanced by valid trials in the spatial frequency discrimination task but was not in the location discrimination task, whereas the contralateral N1 was larger for invalid trials than for valid trials in both tasks.

CONCLUSION

The results indicate that involuntary allocation of attention involves different mechanisms from voluntary allocation of attention.

[The cultivation, freezing-state preservation and resuscitation of human iris pigment epithelial cells in vitro]

PURPOSE

To establish the culture of human iris pigment epithelial cells in vitro and study the freezing-state preservation and resusciation.

METHODS

The iris pigment epithelial specimens from human eyes were cultured in vitro. Based on the cell-frozen principle, the cultured cells were collected, then frozen in liquid nitrogen and resuscitation.

RESULTS

Cultured iris pigment epithelial cells were obtained. Under the inverted light microscope, primary cells appeared multigonal and arranged in monolayer, there were abundant pigment granules in the cytoplasm and the nuclei each of which contained 1 or 2 nuceoli wre relatively transparent. Under the transmission electron microscope, there were plenty of microvilli at the cell membrane and desmosomes present in the intercellular space. 6 groups of cells were frozen. The resuscitation exeriment was carried out for 4 times, every times being successful. All of the resuscitated rates were more than 90%.

CONCLUSION

The human iris pigment epithelial cells were cultured in vitro successfully, they can also be frozen and resuscitated, which will be useful in studies of pathogenesis for some eye disease.

[To screen, clone and sequence TIGR gene mutation in Chinese patients with primary open- angle glaucoma]

OBJECTIVE

To study trabecular meshwork induced glucocorticoid response protein (TIGR) gene mutation in Chinese patients with primary open-angle glaucoma (POAG).

METHODS

(1) From 70 patients with POAG and 20 normal controls, TIGR gene which consists of three exons (7 pairs of primer) was amplified by polymerase chain reaction (PCR). The mutation of PCR amplification products was evaluated by single-stranded conformation polymorphism (SSCP). (2) After the above PCR products were cloned into the PT-Adv vectors, the construction plasmids were evaluated by Ecor I endonuclease and direct sequence was performed.

RESULTS

(1) With SSCP screening, the single strand band abnormality was found in the middle fragments of the third exon (the sixth pair of primer) of TIGR gene in two patients with POAG, but the control group appeared normal. (2) The two samples using clone and sequence showed that one had a 'GAT'- to- 'AAT' transition at amino acid Asp 338 Asn mutation; the base sequence of another one had no change. These results suggested that mutation rate of TIGR gene in Chinese patients with POAG be only 1.4% (1/70), being lower than that of foreigners.

CONCLUSION

The pathogenesis of Chinese patients with POAG may be related with TIGR gene mutation, but the mutation rate is lower than that in foreigners, indicating that the mechanism of POAG in China and aboard is different and the pathogenesis of POAG has difference in regions and races.

Reporter LacZ gene transfer into cultured ocular cells of human eyes in vitro

OBJECTIVE

To investigate whether a reporter LacZ gene could be transferred into cultured ocular cells of human eyes in vitro.

METHODS

Fibroblast cells of Tenon's capsule, trabecular meshwork cells, and muscle cells in the ciliary body of human eyes were cultured and the pcDNA3-LacZ gene was transferred into these cells using a cationic liposome delivery system. The cells were subsequently fixed with 4% paraformaldehyde, mixed with X-gal, then observed under a microscope.

RESULTS

Blue stain was seen in the cytoplasm of the cultured cells under the microscope, demonstrating the successful transfer of the LacZ gene into these cells.

CONCLUSION

Reporter LacZ gene was easily transferred into the cultured ocular cells in vitro. This provides insights into the transfer of the genes into these cells to study the pathogenesis and therapy of glaucoma.