The biomineralization of silica induced stress tolerance in plants: a case study for aluminum toxicity.

Biomineralization in plant roots refers to the process of cell-induced self-assembly to form nanostructures on the root surface. Silicon (Si) is the second most abundant element in soils, and beneficial to plant growth. Meanwhile, silicon is shown to participate in the process of biomineralization, which is useful for improving mechanical strength and alleviating biotic and abiotic stress, for example silicic acid polymerizes to form amorphous silica (SiO2-nH2O) in the process of growing to resist fungi and environmental stress. This process alters physical and chemical properties of cell wall. However, the mechanistic basis of this process remains unclear. Aluminum toxicity is a major constraint affecting plant performance in acid soil. This paper summarizes recent research advances in the field of plant biomineralization and describes the effects of silicon biomineralization on plant aluminum tolerance and its adaptive significance, using aluminum toxicity as a case study.

The Function of BBX Gene Family under Multiple Stresses in Nicotiana tabacum.

B-box (BBX) is a zinc finger transcription factor, which is involved in regulating the growth and development of plants and resisting various stresses. In this study, 43 NtBBX genes were identified and divided into five subgroups in tobacco. The members in each subgroup had similar characteristics. The promoter region of NtBBX genes had cis-acting elements related to light response, hormone regulation and stress response. Transcriptome analysis showed that NtBBX30 was significantly up-regulated, and NtBBX12, NtBBX13, NtBBX16 and NtBBX17 were significantly down-regulated under abiotic stresses. The NtBBX genes also responded to the infection of Ralstonia solanacearum. NtBBX9, NtBBX1, NtBBX15 and NtBBX17 showed the greatest response under stresses. The NtBBX genes are expressed in various degrees under different tissues. This research will provide a solid foundation for further study of the biological function of NtBBX genes in tobacco.

Effects of Cadmium Stress on Root and Root Border Cells of Some Vegetable Species with Different Types of Root Meristem.

Cadmium is one of the most toxic heavy metals and can be easily absorbed by plants, affecting root growth. Root border cells (RBCs), that are located in the periphery of the root cap and originate from the root cap meristem, represent a convenient tool to study the toxic effects of Cd on root performance. In this work, vegetables with contrasting types of root apical meristem (RAM) organizations were used. The open RAM organizations included pea and cucumber, and the closed RAM organizations included tomato, chili, and eggplant. The number of RBCs were significantly higher in the species possessing open RAM organization: pea (11,330 cells per root) > cucumber (8200) > tomato (2480) > eggplant (1830) > chili (1320). The same trend was observed for cell viability: pea (61%) > cucumber (59%) > tomato (49%) > eggplant (44%) > chili (42%). Pea and cucumber had higher relative radicle elongation rates and a lower increase in stress-induced accumulation of malondialdehyde (MDA), making them more resistant to Cd stress than the vegetables with close RAM organization. Under Cd treatment, the number and viability of RBCs in vegetables with both types of RAM organization were significantly decreased. However, the decreasing ratio of the number and viability of RBCs in pea and cucumber was higher than in tomato, chili, and eggplant. Taken together, the plants with the open-type RAM are more tolerant to Cd, and it can be speculated that the cadmium tolerance of the vegetables may be correlated with the number and viability of RBCs in response to cadmium stress.

Genome-wide identification and expression analyses of late embryogenesis abundant (LEA) gene family in tobacco (Nicotiana tabacum L.) reveal their function in abiotic stress responses.

Late embryogenesis abundant (LEA) proteins play an important role in plant growth and response to abiotic stresses. However the late embryogenesis abundant (LEA) gene family in Nicotiana tabacum has not been systematically studied. In this study, 123 NtLEA genes were identified in Nicotiana tabacum, and divided into 8 groups, including LEA_1, LEA_2, LEA_3, LEA_4, LEA_5, LEA_6, DHN (dehydratin) and SMP (Seed Maturation Protein). The LEA_2 group is the most abundant of the NtLEA family. The gene structure, conserved motifs, subcellular localization and physicochemical properties of the NtLEA genes were analyzed. RNA-seq and qPCR analyses showed that the NtLEA genes were significantly induced under two different abiotic stresses and showed different expression patterns. The expression patterns of 35 NtLEA genes responding to ABA and 3 NtLEA genes responding to NaCl abiotic stress, respectively, were characterized. The protein-protein interaction network revealed that most NtLEA proteins (>78%) had the potential function to enhance tobacco resistance to abiotic stress. The transcriptional regulatory network showed that 21 transcription factor families were involved in regulating the expression of the NtLEA genes. These results are beneficial for future studies of the function of the NtLEA genes.

Human umbilical cord mesenchymal stem cells-derived exosomes for treating traumatic pancreatitis in rats.

BACKGROUND: The therapeutic and protective effects of human umbilical cord mesenchymal stem cells-exosomes (hucMSC-Exs) on traumatic pancreatitis (TP) remain unknown. Here, we established a rat model of TP and evaluated and compared the therapeutic effects of hUC-MSCs and hucMSC-Exs. METHODS: HucMSC-Exs were obtained by ultracentrifugation and identified using transmission electron microscopy and western blot analysis. TP rats were treated by tail vein injection of hUC-MSCs and hucMSC-Exs. Their homing in rats was observed by performing fluorescence microscopy. The degree of pancreatic tissue damage was assessed by HE staining, the expression levels of amylase, lipase, and inflammatory cytokines were detected by ELISA, apoptosis was detected by TUNEL assay, and the expression levels of various apoptosis-related proteins were detected by western-blot. The expression levels of apoptosis-related molecular markers were detected by RT-qPCR. RESULTS: The colonization of exosomes was observed in pancreatic tissue. Compared to TP group, the histopathological score of pancreas was significantly decreased in the TP + hUC-MSCs group and TP + hucMSC-Exs group (P < 0.05). Compared to TP group, the activity of serum amylase and lipase was significantly decreased (P < 0.05). The expression levels of IL-6 and TNF-α were significantly decreased, while those of IL-10 and TGF-ß were significantly increased (P < 0.05). The apoptosis index of the TP group was significantly increased (P < 0.05), whereas that of the TP + hUC-MSCs and TP + hucMSC-Exs groups was significantly decreased (P < 0.05). Compared to TP group, the expression levels of Bax, Bcl-2, and Caspase-3 were significantly decreased in the TP + hUC-MSCs group and TP + hucMSC-Exs group (P < 0.05). CONCLUSION: HucMSC-Exs can colonize injured pancreatic tissue, inhibit the apoptosis of acinar cells, and control the systemic inflammatory response to facilitate the repair of pancreatic tissue.

Monosialotetrahexosylganglioside in the treatment of chronic oxaliplatin-induced peripheral neurotoxicity: TJMUCH-GI-001, a randomised controlled trial.

BACKGROUND: Chronic oxaliplatin-induced peripheral neurotoxicity (OIPN) is the most troublesome and dose-limiting side effect of oxaliplatin. There is no effective treatment for chronic OIPN. We conducted a randomised controlled trial to investigate the efficacy of monosialotetrahexosylganglioside (GM1) in treating chronic OIPN. METHODS: In this single-centre, double-blind, phase Ⅲ trial, gastrointestinal cancer patients with persistent chronic OIPN were randomised in 1:1 ratio to receive either GM1 or placebo at Tianjin Medical University Cancer Institute and Hospital, China. GM1 was dosed at 60 mg daily for every 3 weeks or 40 mg daily for every 2 weeks. Seven- and fourteen- day infusions were administered to concurrent oxaliplatin users and oxaliplatin discontinuation patients, respectively. The primary endpoint was the relief of neurotoxicity (≥30% improvement), measured by a newly developed patient reported outcome measure (MCIPN) based on prior questionnaires including the European Organization for Research and Treatment of Cancer Quality of Life Chemotherapy Induced Peripheral Neuropathy Questionnaire twenty-item scale. Visual analogue score (VAS) was used as another instrument for patients to evaluate the total Chronic OIPN treatment effect. VAS responders (≥30% improvement), double responders (≥30% improvement in both MCIPN and VAS), and high responders (≥50% improvement in the MCIPN total score) were also calculated. The secondary endpoints were safety and quality of life. The additional endpoints are progression-free survival (PFS), disease-free survival (DFS), overall survival (OS), and tumour response. (Trial registration number: NCT02486198 at ClinicalTrials.gov). FINDINGS: Between May 2015 to December 2017, 145 patients were randomly assigned to receive either GM1 (n=73) and placebo (n=72). Majority of the patients in both arms (90% in GM1 and 83% in placebo) continued receiving oxaliplatin on the trial. More patients responded in the GM1 group than in the placebo group (MCIPN responders: 53% vs 14%, VAS responders: 49% vs 22%, double responders: 41% vs 7%, and high responders: 32% vs 13%, all P < ·01). Analyses were also performed in concurrent oxaliplatin users. The results were consistent with those of the whole group. No deleterious effects of GM1 on survival or tumour response were found. There were no ≥G3 GM1-related adverse events. INTERPRETATION: In patients with chronic OIPN, the use of GM1 reduces the severity of chronic OIPN compared with placebo. FUNDING: This work was supported by clinical trial development fund of Tianjin Medical University Cancer Institute and Hospital (No.C1706).

Extracellular silica nanocoat formed by layer-by-layer (LBL) self-assembly confers aluminum resistance in root border cells of pea (Pisum sativum).

BACKGROUND: Soil acidity (and associated Al toxicity) is a major factor limiting crop production worldwide and threatening global food security. Electrostatic layer-by-layer (LBL) self-assembly provides a convenient and versatile method to form an extracellular silica nanocoat, which possess the ability to protect cell from the damage of physical stress or toxic substances. In this work, we have tested a hypothesis that extracellular silica nanocoat formed by LBL self-assembly will protect root border cells (RBCs) and enhance their resistance to Al toxicity. RESULTS: Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were used to compare the properties of RBCs surface coated with nanoshells with those that were exposed to Al without coating. The accumulation of Al, reactive oxygen species (ROS) levels, and the activity of mitochondria were detected by a laser-scanning confocal microscopy. We found that a crystal-like layer of silica nanoparticles on the surface of RBCs functions as an extracellular Al-proof coat by immobilizing Al in the apoplast and preventing its accumulation in the cytosol. The silica nanoshells on the RBCs had a positive impact on maintaining the integrity of the plasma and mitochondrial membranes, preventing ROS burst and ensuring higher mitochondria activity and cell viability under Al toxicity. CONCLUSIONS: The study provides evidence that silica nanoshells confers RBCs Al resistance by restraining of Al in the silica-coat, suggesting that this method can be used an efficient tool to prevent multibillion-dollar losses caused by Al toxicity to agricultural crop production.

Somatostatin Reduces the Acute Lung Injury of Mice via Increasing the Affinity of Glucocorticoid Receptor.

BACKGROUND/AIMS: Although it has been reported that somatostatin (SOM) upregulated the level of 90-kD heat shock protein (Hsp90), which participates in the inflammatory regulation by its client proteins, such as glucocorticoid receptor (GR), it remains unclear if it has a protective role against acute lung injury (ALI). METHODS: ALI model was established by the injection of oleic acid (OA) into the tail vein of mice. Lung injury was assessed by histological analysis, lung water content and arterial blood gases. The levels of Hsp90 and GR, the binding capacity and the affinity of GR were examined. RESULTS: It was showed that pretreatment with SOM significantly increased Hsp90 levels and alleviated lung injuries in OA-injected mice. Furthermore, SOM increased the GR expression and improved the affinity of the GR in animals with lung injury. However, little alteration was found in the maximum binding capacity of the GR in mice with or without SOM. CONCLUSION: The data indicate SOM exerts a protective effect by increasing Hsp90 abundant and further enhancing the affinity of the GR. The beneficial effects of SOM treatment provide a new strategy for modulation of GR efficiency and alleviation of acute lung injury.

Chronic caffeine exposure attenuates blast-induced memory deficit in mice.

OBJECTIVE: To investigate the effects of three different ways of chronic caffeine administration on blast- induced memory dysfunction and to explore the underlying mechanisms. METHODS: Adult male C57BL/6 mice were used and randomly divided into five groups: control: without blast exposure, con-water: administrated with water continuously before and after blast-induced traumatic brain injury (bTBI), con-caffeine: administrated with caffeine continuously for 1 month before and after bTBI, pre-caffeine: chronically administrated with caffeine for 1 month before bTBI and withdrawal after bTBI, post-caffeine: chronically administrated with caffeine after bTBI. After being subjected to moderate intensity of blast injury, mice were recorded for learning and memory performance using Morris water maze (MWM) paradigms at 1, 4, and 8 weeks post-blast injury. Neurological deficit scoring, glutamate concentration, proinflammatory cytokines production, and neuropathological changes at 24 h, 1, 4, and 8 weeks post-bTBI were examined to evaluate the brain injury in early and prolonged stages. Adenosine A1 receptor expression was detected using qPCR. RESULTS: All of the three ways of chronic caffeine exposure ameliorated blast-induced memory deficit, which is correlated with the neuroprotective effects against excitotoxicity, inflammation, astrogliosis and neuronal loss at different stages of injury. Continuous caffeine treatment played positive roles in both early and prolonged stages of bTBI; pre-bTBI and post-bTBI treatment of caffeine tended to exert neuroprotective effects at early and prolonged stages of bTBI respectively. Up-regulation of adenosine A1 receptor expression might contribute to the favorable effects of chronic caffeine consumption. CONCLUSION: Since caffeinated beverages are widely consumed in both civilian and military personnel and are convenient to get, the results may provide a promising prophylactic strategy for blast-induced neurotrauma and the consequent cognitive impairment.

The glucocorticoid dexamethasone inhibits U937 cell adhesion and neutrophil release via RhoA/ROCK1-dependent and independent pathways.

AIMS: The aim of the present study was to investigate the role of the Ras homolog family member A (RhoA)/Rho-associated coiled-coil-containing protein kinase 1 (ROCK1) signaling pathway in the inhibition of inflammatory responses by the glucocorticoid dexamethasone (Dex). METHODS: The inhibitory effects of Dex and Rho-kinase inhibitor fasudil (Fas) on phorbol ester-induced release of O2(-) and MPO from neutrophils and on U937 mononuclear cell adhesion were examined along with the expression and activity levels of RhoA and ROCK1. RESULTS: High doses of Dex rapidly inhibited the release of O2(-) and myeloperoxidase (MPO) from neutrophils and the adhesion of U937 cells, while Fas was only found to inhibit U937 cell adhesion. Additionally, Dex suppressed ROCK1 activity. However, Dex had no effects on ROCK1 or RhoA expression levels or on RhoA activity. Neither the glucocorticoid receptor antagonist mifepristone (RU-486) nor the protein synthesis inhibitor cycloheximide (CHX) was able to suppress the effects of Dex (p>0.05). CONCLUSIONS: The present findings indicate that Dex suppressed neutrophil release through ROCK1-independent mechanisms and inhibited the adhesion of U937 mononuclear cells through ROCK1-dependent non-genomic mechanisms that did not involve RhoA.

EF1α is a suitable housekeeping gene for RT-qPCR analysis during osteogenic differentiation of mouse bone marrow-derived mesenchymal stem cells.

The expression of predominant housekeeping genes used in RT-qPCR can vary during development and differentiation. The frequently used housekeeping genes (ACTB, GAPDH, 18S rRNA, EF1α and RPL 13a) were evaluated during an early stage of the osteogenic differentiation of mouse bone marrow-derived mesenchymal stem cells (mMSCs) (under normal conditions or treated with CCG-4986) to identify housekeeping genes whose expression remained constant during osteogenic differentiation. When we used RGS4 mRNA, which was determined as copy number per µg of total RNA, to normalize gene expression, we observed that the relative EF1α expression profile was consistent with RGS4 expression after treatment with CCG-4986. All the relative expression profiles of the EF1α, 18S rRNA, and RPL13a housekeeping genes were consistent with RGS4 profiles determined by measuring mRNA copies under normal osteogenic differentiation conditions. The expression profiles calibrated by ACTB and GAPDH were not consistent with those determined using mRNA copy number in untreated cells or cells treated with CCG-4986 under osteogenic differentiation conditions. Under normal osteogenic differentiation conditions, EF1α, 18S rRNA, and RPL 13a are suitable housekeeping genes for RT-qPCR analysis. However, EF1α is the only suitable gene upon CCG-4986 treatment.

Adenosine A2A receptor deficiency alleviates blast-induced cognitive dysfunction.

Traumatic brain injury (TBI), particularly explosive blast-induced TBI (bTBI), has become the most prevalent injury among military personnel. The disruption of cognitive function is one of the most serious consequences of bTBI because its long-lasting effects prevent survivors fulfilling their active duty and resuming normal civilian life. However, the mechanisms are poorly understood and there is no treatment available. This study investigated the effects of adenosine A2A receptor (A2AR) on bTBI-induced cognitive deficit, and explored the underlying mechanisms. After being subjected to moderate whole-body blast injury, mice lacking the A2AR (A2AR knockout (KO)) showed less severity and shorter duration of impaired spatial reference memory and working memory than wild-type mice did. In addition, bTBI-induced cortical and hippocampal lesions, as well as proinflammatory cytokine expression, glutamate release, edema, cell loss, and gliosis in both early and prolonged phases of the injury, were significantly attenuated in A2AR KO mice. The results suggest that early injury and chronic neuropathological damages are important mechanisms of bTBI-induced cognitive impairment, and that the impairment can be attenuated by preventing A2AR activation. These findings suggest that A2AR antagonism is a potential therapeutic strategy for mild-to-moderate bTBI and consequent cognitive impairment.

Oat ß-glucan inhibits lipopolysaccharide-induced nonalcoholic steatohepatitis in mice.

Nonalcoholic steatohepatitis (NASH) is part of the spectrum of nonalcoholic fatty liver disease. However, there are few suitable animal models to study the pathogenesis of NASH or very limited advances in the prevention. Our aims were to establish a mouse model of NASH by intraperitoneally injecting lipopolysaccharide (LPS) at a dose of 1.5 mg per kg body weight per day for 6 weeks and to investigate the potential inhibitory effects of oat ß-glucan (1%, 5%, or 10%) added to a specific pathogen-free diet. Intraperitoneal injection of LPS for 6 weeks increased serum LPS levels; decreased serum glucagon-like peptide-2 levels; triggered abnormal aminotransferase activity, glucose intolerance, and insulin resistance; and increased hepatic proinflammatory cytokines (tumor necrosis factor-α, interleukin-6, interleukin-1ß), triglyceride, and malonyl dialdehyde levels; but reduced hepatic superoxide dismutase activity. Histologic evaluation revealed evidence of hepatic steatosis, inflammation, and mild necrosis in LPS-treated mice. Dietary supplementation of oat ß-glucan prevented most of the LPS-induced metabolic disorders, and improved hepatic steatosis and inflammation, although a dose-dependent effect was not observed. In conclusion, oat ß-glucan could inhibit LPS-induced NASH in mice.

The -144C/A polymorphism in the promoter of HSP90beta is associated with multiple organ dysfunction scores.

INTRODUCTION: Variations in genetic background are the leading cause of differential susceptibility to traumatic infection. Heat shock protein 90 (HSP90), a broadly distributed and conserved molecule, regulates inflammation under stressful and traumatic conditions. However, the relationships between HSP90 genetic polymorphisms, post-traumatic inflammatory responses and organ function remain unknown. METHODS: A total of 286 healthy volunteers and patients with severe trauma took part in a single nucleotide polymorphism (SNP)-based analysis of the HSP90beta gene and a clinical association analysis. HSP90beta and TNF-alpha levels were determined using quantitative PCR and western blot. The transcriptional activity of the HSP90beta promoter was assayed using the Dual-Luciferase Reporter Assay System. RESULTS: The minor allele frequencies for the SNP located at -144 bp relative to the HSP90beta transcriptional start site were 28.47% and 28.52% in the normal and trauma populations, respectively; no significant differences were found between these two distributions. However, the results showed that a promoter containing the -144A allele had a higher transcriptional activity than did a promoter containing the wild-type -144C allele. Furthermore, the -144A promoter induced high expression of HSP90beta and low expression of the inflammatory factor TNF-alpha in a lipopolysaccharide-induced inflammatory model. A clinical association analysis showed that the multiple organ dysfunction scores for -144AA genotype carriers were significantly lower than those of -144CC carriers following trauma. No significant correlations were found between the presence of the two alleles and the incidence of sepsis. CONCLUSIONS: These results indicate that differences in expression caused by the -144 polymorphism in the HSP90beta promoter are associated with cellular inflammatory responses and the severity of organ injury. These findings will aid in risk assessment and early prevention of complications for patients with severe trauma.

Supplementation with oat protein ameliorates exercise-induced fatigue in mice.

Oat protein was purified from oat meal and its effects on swimming performance and related biochemical parameters were investigated. Thirty male Kun-ming mice were divided into the normal control, the oat meal and the oat protein group (n = 10). They were fed with a laboratory food for 30 days, then were subjected to swim to exhaustion. Their swimming endurance and the major metabolic substrates were measured from serum, liver and muscle. The results showed that no significant differences were observed in swimming endurance test between the normal control group and the oat protein group (P > 0.05). Mice in the oat meal group had significantly longer swimming endurance compared to the normal control group (P < 0.05). Furthermore, dietary oat protein increased the levels of liver glycogen, enhanced the activities of lactic dehydrogenase and superoxide dismutase, and decreased the levels of blood urea nitrogen and malondialdehyde in serum. These results suggested that oat protein was effective in improving the physiological condition of the mice.

Dexamethasone inhibits U937 cell adhesion via the down-regulation of ROCK1 activity.

OBJECTIVE: To explore the effect of dexamethasone (DEX) on monocyte adhesion function and its underlying mechanism. METHODS: The effects of DEX and fasudil on adhesion of cultured U937 monocytes to human umbilical vein endothelial cells (HUVEC) following stimulation with phorbol myristate acetate (PMA) were studied; Changes in the Rho-associated coiled-coil protein kinase 1 (ROCK1) protein content and activity were evaluated. RESULTS: DEX and fasudil significantly inhibited U937 cell adhesion rates under PMA stimulation and inhibited ROCK1 activity. Mifepristone (RU-486) and cycloheximide (CHX) did not alter these effects of DEX. CONCLUSIONS: DEX interferes with the adhesion function of U937 cells through the inhibition of ROCK1 activity.

Roles of Rho-associated coiled-coil protein kinase in multiple cell behaviors.

Rho-associated coiled-coil protein kinase (ROCK) is a serine/threonine kinase that belongs to AGC family of kinases. By inducing the formation of stress fibers and reorganizing the cytoskeleton, it is involved in many biological behaviors of cells including cell contraction, cell migration, cell division, and morphological changes, and thus exerts important roles in regulating the multiple functions of cells.

Ski, a modulator of wound healing and scar formation in the rat skin and rabbit ear.

We recently demonstrated that Ski is a novel wound healing-related factor that promotes fibroblast proliferation and inhibits collagen secretion. Here, we show that increasing local Ski expression by gene transfer not only significantly accelerated wound healing by relieving inflammation, accelerating re-epithelialization and increasing formation of granulation tissue, but also reduced scar formation by decreasing collagen production in rat dermal wounds. Similarly, ski gene transfer accelerated wound healing, reduced the protuberant height and volume of scars and increased collagen maturity in a hypertrophic scar model in the rabbit ear. Conversely, reducing Ski expression in the wound by RNA interference resulted in significantly slower wound healing and increased scar area in rat dermal wounds. We demonstrated that these effects of Ski are associated with transforming growth factor-ß-mediated signalling pathways through both Smad2/3-dependent and Smad-independent pathways. Together, our results define a dual role for Ski in promoting wound healing and alleviating scar formation, identifying a new target for therapeutic approaches to preventing scar hyperplasia and accelerating wound healing.

[Effect of (S)-4C3HPG on brain damage in the acute stage of moderate traumatic brain injury model of mice and underlying mechanism].

The aim of this study is to investigate the effect of (S)-4-carboxy-3-hydroxy-phenylglycine [(S)-4C3HPG], a mixed group I glutamate metabotropic receptor antagonist and a group II agonist, on impairment in a cortical impact model of traumatic brain injury (TBI) in mice and to elucidate the possible mechanisms. Mice were injected (i.p.) with saline, 1 mg/kg (S)-4C3HPG, 5 mg/kg (S)-4C3HPG and 10 mg/kg (S)-4C3HPG (n=10 per group), respectively, at 30 min before moderate TBI. Neurological deficit scores, water content in injured brain and glutamate concentration in cerebral spinal fluid (CSF) were detected at 24 h after TBI. The expressions of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) mRNA in injured cortex were also detected by real-time RT-PCR. The results showed that the neurological deficits and cerebral edema were significantly attenuated in mice pretreated with (S)-4C3HPG (5 and 10 mg/kg respectively) compared with those in mice pretreated with saline. Furthermore, (S)-4C3HPG treatment also decreased the glutamate concentration in CSF and the expressions of TNF-α and IL-1ß mRNA remarkably in a dose-dependent manner. These results suggest that (S)-4C3HPG treatment attenuates cortical impact-induced brain injury possibly via suppression of glutamate release and inhibition of excessive inflammatory cytokine production. These findings highlight the potential benefit of glutamate metabotropic receptor ligand for preventing TBI.

Application of an oligonucleotide microarray-based nano-amplification technique for the detection of fungal pathogens.

BACKGROUND: The traditional techniques for diagnosis of invasive fungal infections in the clinical microbiology laboratory need improvement. These techniques are prone to delay results due to their time-consuming process, or result in misidentification of the fungus due to low sensitivity or low specificity. The aim of this study was to develop a method for the rapid detection and identification of fungal pathogens. METHODS: The internal transcribed spacer two fragments of fungal ribosomal DNA were amplified using a polymerase chain reaction for all samples. Next, the products were hybridized with the probes immobilized on the surface of a microarray. These species-specific probes were designed to detect nine different clinical pathogenic fungi including Candida albicans, Candida tropocalis, Candida glabrata, Candida parapsilosis, Candida krusei, Candida lusitaniae, Candida guilliermondii, Candida keyfr, and Cryptococcus neoformans. The hybridizing signals were enhanced with gold nanoparticles and silver deposition, and detected using a flatbed scanner or visually. RESULTS: Fifty-nine strains of fungal pathogens, including standard and clinically isolated strains, were correctly identified by this method. The sensitivity of the assay for Candida albicans was 10 cells/mL. Ten cultures from clinical specimens and 12 clinical samples spiked with fungi were also identified correctly. CONCLUSIONS: This technique offers a reliable alternative to conventional methods for the detection and identification of fungal pathogens. It has higher efficiency, specificity and sensitivity compared with other methods commonly used in the clinical laboratory.