In search for better pharmacological prophylaxis for acute mountain sickness: looking in other directions

Despite decades of research, the exact pathogenic mechanisms underlying acute mountain sickness (AMS) are still poorly understood. This fact frustrates the search for novel pharmacological prophylaxis for AMS. The prevailing view is that AMS results from an insufficient physiological response to hypoxia and that prophylaxis should aim at stimulating the response. Starting off from the opposite hypothesis that AMS may be caused by an initial excessive response to hypoxia, we suggest that directly or indirectly blunting-specific parts of the response might provide promising research alternatives. This reasoning is based on the observations that (i) humans, once acclimatized, can climb Mt Everest experiencing arterial partial oxygen pressures (PaO2) as low as 25 mmHg without AMS symptoms; (ii) paradoxically, AMS usually develops at much higher PaO2 levels; and (iii) several biomarkers, suggesting initial activation of specific pathways at such PaO2, are correlated with AMS. Apart from looking for substances that stimulate certain hypoxia triggered effects, such as the ventilatory response to hypoxia, we suggest to also investigate pharmacological means aiming at blunting certain other specific hypoxia-activated pathways, or stimulating their agonists, in the quest for better pharmacological prophylaxis for AMS.

Role of mitochondrial ATP-sensitive potassium channel-mediated PKC-ε in delayed protection against myocardial ischemia/reperfusion injury in isolated hearts of sevoflurane-preconditioned rats

This study aimed to determine the role of mitochondrial adenosine triphosphate-sensitive potassium (mitoK_ATP) channels and protein kinase C (PKC)-ε in the delayed protective effects of sevoflurane preconditioning using Langendorff isolated heart perfusion models. Fifty-four isolated perfused rat hearts were randomly divided into 6 groups (n=9). The rats were exposed for 60 min to 2.5% sevoflurane (the second window of protection group, SWOP group) or 33% oxygen inhalation (I/R group) 24 h before coronary occlusion. The control group (CON) and the sevoflurane group (SEVO) group were exposed to 33% oxygen and 2.5% sevoflurane for 60 min, respectively, without coronary occlusion. The mitoK_ATP channel inhibitor 5-hydroxydecanoate (5-HD) was given 30 min before sevoflurane preconditioning (5-HD+SWOP group). Cardiac function indices, infarct sizes, serum cardiac troponin I (cTnI) concentrations, and the expression levels of phosphorylated PKC-ε (p-PKC-ε) and caspase-8 were measured. Cardiac function was unchanged, p-PKC-ε expression was upregulated, caspase-8 expression was downregulated, cTnI concentrations were decreased, and the infarcts were significantly smaller (P<0.05) in the SWOP group compared with the I/R group. Cardiac function was worse, p-PKC-ε expression was downregulated, caspase-8 expression was upregulated, cTnI concentration was increased and infarcts were larger in the 5-HD+SWOP group (P<0.05) compared with the SWOP group. The results suggest that mitoK_ATP channels are involved in the myocardial protective effects of sevoflurane in preconditioning against I/R injury, by regulating PKC-ε phosphorylation before ischemia, and by downregulating caspase-8 during reperfusion.

Using fast moving electrode to achieve overvoltage breakdown of gas switch stressed with high direct voltages

A small-scale fast risetime gas switch attached to a 50 Ω pulse forming line is tested. It includes a fast moving electrode and a fixed electrode. For the applied direct voltages, such as 2.8 kV, 2.0 kV, and 1.0 kV, the risetimes of this switch are tested to be ∼3.8 ns, ∼2.3 ns, and ∼1.1 ns, respectively, while the risetimes of a switch with two fixed electrodes are about ∼10.1 ns, ∼9.0 ns, and ∼3.6 ns. The results of high-speed photography and laser interferometry reveal that the moving electrode will obviously shorten discharge spark length but almost will not change the inter-electrodes gas pressure. The reason of shortening spark length is the existence of the discharge time delay of gas switch. After moving to the static breakdown spacing, the fast moving electrode will move on for an additional distance within the discharge time delay, which makes gas switch achieve overvoltage breakdown under high direct voltages and therefore leads to shorter spark length and faster switch risetime.

The gender difference in effect of sevoflurane exposure on cognitive function and hippocampus neuronal apoptosis in rats

OBJECTIVE

Anesthesia and surgery can induce postoperative cognitive dysfunction. Ser-133 phosphorylation sites of cAMP-response element binding protein (CREB) is a key gene that mediate a variety of downstream transcription initiation factors, regulate neuronal survival and promote the expression of a large number of genes. Thus, CREB may play a role in this impairment. We hypothesize that and sevoflurane-induced cognitive impairment possibly via inhibiting the expression of CREB downstream genes and proteins.

MATERIALS AND METHODS

To test this hypothesis, adult Sprague-Dawley rats were subjected to sevoflurane exposure and were tested with a series of behavioral experiments (open field, passive avoidance test and Morris water maze test) at different time (1 d to 95 d). Besides, blood gas changes and expiratory sevoflurane concentrations were examined at 2 h; the levels of phosphorylated CREB 1, the protein Bcl-2, Caspase-8 and Caspase-3 were assessed at 1 week and 3 months after anesthesia. We also conducted a comparison in sevoflurane-induced cognitive impairment between male and female rats.

RESULTS AND CONCLUSIONS

Here, we found that sevoflurane anesthesia can impair short-term cognitive function, which may be via down-regulating p-CREB1 and Bcl-2 expression and up-regulating Caspase-8 expression to reduce hippocampus neuronal apoptosis, and male rats suffered a more severe cognitive dysfunction than female rats. In addition, sevoflurane can produce a reversible long-term cognitive dysfunction in rats.

A flowing liquid lithium limiter for the Experimental Advanced Superconducting Tokamak

A program involving the extensive and systematic use of lithium (Li) as a "first," or plasma-facing, surface in Tokamak fusion research devices located at Institute of Plasma Physics, Chinese Academy of Sciences, was started in 2009. Many remarkable results have been obtained by the application of Li coatings in Experimental Advanced Superconducting Tokamak (EAST) and liquid Li limiters in the HT-7 Tokamak-both located at the institute. In furtherance of the lithium program, a flowing liquid lithium (FLiLi) limiter system has been designed and manufactured for EAST. The design of the FLiLi limiter is based on the concept of a thin flowing film which was previously tested in HT-7. Exploiting the capabilities of the existing material and plasma evaluation system on EAST, the limiter will be pre-wetted with Li and mechanically translated to the edge of EAST during plasma discharges. The limiter will employ a novel electro-magnetic pump which is designed to drive liquid Li flow from a collector at the bottom of limiter into a distributor at its top, and thus supply a continuously flowing liquid Li film to the wetted plasma-facing surface. This paper focuses on the major design elements of the FLiLi limiter. In addition, a simulation of incoming heat flux has shown that the distribution of heat flux on the limiter surface is acceptable for a future test of power extraction on EAST.

Immune response of γδT cells in Schistosome japonicum-infected C57BL/6 mouse liver

Systematic evaluation of the role of γδT cells during the Schistosoma japonicum infection has not been reported, despite the fact that γδT cells contribute to many infectious diseases in innate immunity. Therefore, the aim of this study was to observe the properties of γδT cells in the liver of C57BL/6 mice infected by S. japonicum. In this report, using immuno-fluorescent histological analysis, γδT cells were found around hepatic granulomatous. Moreover, the flow cytometry results revealed that the percentage of hepatic γδT cells increased significantly after S. japonicum infection. More interestingly, a subset of CD3(-)γδTCR(+) cells were found and markedly increased after infection. Furthermore, expression of activation markers (CD25 and CD69) and cytokine profiles were detected in these hepatic CD3(+)γδTCR(+) and CD3(-)γδTCR(+) cells. The significantly higher level of CD69, IL-4 and IL-17 were observed in CD3(+)γδTCR(+) cells after infection, suggesting that CD3(+)γδTCR(+) cells instead of CD3(-)γδTCR(+) cells might play a predominant role during the infection. Finally, our results indicated that the expression of NKG2D on CD3(+)γδTCR(+) cells was higher than that on CD3(-)γδTCR(+) cells. Collectively, γδT cells could play an important role in the liver of C57BL/6 mouse during japonicum infection.

TBX6 null variants and a common hypomorphic allele in congenital scoliosis

BACKGROUND

Congenital scoliosis is a common type of vertebral malformation. Genetic susceptibility has been implicated in congenital scoliosis.

METHODS

We evaluated 161 Han Chinese persons with sporadic congenital scoliosis, 166 Han Chinese controls, and 2 pedigrees, family members of which had a 16p11.2 deletion, using comparative genomic hybridization, quantitative polymerase-chain-reaction analysis, and DNA sequencing. We carried out tests of replication using an additional series of 76 Han Chinese persons with congenital scoliosis and a multicenter series of 42 persons with 16p11.2 deletions.

RESULTS

We identified a total of 17 heterozygous TBX6 null mutations in the 161 persons with sporadic congenital scoliosis (11%); we did not observe any null mutations in TBX6 in 166 controls (P<3.8×10(-6)). These null alleles include copy-number variants (12 instances of a 16p11.2 deletion affecting TBX6) and single-nucleotide variants (1 nonsense and 4 frame-shift mutations). However, the discordant intrafamilial phenotypes of 16p11.2 deletion carriers suggest that heterozygous TBX6 null mutation is insufficient to cause congenital scoliosis. We went on to identify a common TBX6 haplotype as the second risk allele in all 17 carriers of TBX6 null mutations (P<1.1×10(-6)). Replication studies involving additional persons with congenital scoliosis who carried a deletion affecting TBX6 confirmed this compound inheritance model. In vitro functional assays suggested that the risk haplotype is a hypomorphic allele. Hemivertebrae are characteristic of TBX6-associated congenital scoliosis.

CONCLUSIONS

Compound inheritance of a rare null mutation and a hypomorphic allele of TBX6 accounted for up to 11% of congenital scoliosis cases in the series that we analyzed. (Funded by the National Basic Research Program of China and others.).

A bio-process inspired synthesis of vaterite (CaCO3), directed by a rationally designed multifunctional protein, ChiCaSifi

A bio-process inspired synthesis of vaterite (CaCO₃) is achieved under the functions of a rationally designed multifunctional protein, ChiCaSifi.

Preparation and analysis of a new bioorganic metallic material

In this study, a synthetic peptide has been utilized to react with 304 stainless steel aiming to generate a bioorganic stainless steel using a facile technique.

Protein engineering of a new recombinant peptide to increase the surface contact angle of stainless steel

Biofouling seriously affects the properties and service life of metal materials.

Systemic lupus erythematosus patients in the low-latitude plateau of China: altitudinal influences

The current study was to investigate the features of hospitalized patients with systemic lupus erythematosus (SLE) at different altitudes. The correlation between SLE activity and altitudinal variations was also explored. Medical records of 1029 patients were retrospectively reviewed. Activity of SLE in each organ system was recorded using the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). There was no significant correlation between SLE activity and altitudes (r = 0.003, p = 0.159). Age at onset for SLE patients at high altitudes was significantly younger than that at low and moderate altitudes (p = 0.022 and p = 0.004, respectively). Age at SLE admission at low altitudes was significant older than those at moderate and high altitudes (p = 0.011 and p < 0.001, respectively). Patients at high altitudes had shorter duration from disease onset to admission than those at moderate altitudes (p = 0.009). Incidence of Sm antibodies-positive for resident patients at high altitudes was 36.4%, which were higher than that at moderate altitudes (p = 0.003). We found increasing trends of CNS activity in active patients; immunological and renal activities in inactive patients were correlated with elevated altitudes (p = 0.024, p = 0.004, p = 0.005), while arthritis scores in active patients showed the tendency of decreasing with the rise of elevation (p = 0.002). Hemoglobin level, red blood cell and platelet counts at high altitudes were significantly lower than those at low altitudes (p < 0.05, respectively). There was no significant difference in hemoglobin level between moderate- and low-altitude groups (p > 0.05). No significant difference in platelet counts between moderate- and high-altitude groups was observed (p > 0.05). Our findings suggest that some clinical features, laboratory tests and activity of main organs in SLE are influenced by altitudes. Furthermore, organ activities of active and inactive SLE patients have different patterns of altitudinal variations. These distinctive variations likely reveal that peculiar environmental factors at high altitudes can affect the development of SLE.

Bile deficiency induces changes in intestinal Cl(-) and HCO3 (-) secretions in mice

AIMS

Biliary tract obstruction is a common clinical lesion. However, the effect of biliary tract obstruction on intestinal secretion is poorly understood. In this study, we made an investigation on intestinal HCO3 (-) and Cl(-) secretions in an experimental model of murine biliary duct ligation.

METHODS

Murine intestinal mucosal HCO3 (-) and Cl(-) secretions were examined in vitro in Ussing chambers by pH-stat and short-circuit current (Isc ) techniques. The mRNA and protein expressions of the cystic fibrosis transmembrane conductance regulator (CFTR) and the Na(+) -K(+) -2Cl(-) cotransporter (NKCC1) were analysed by real-time PCR, western blot and immunohistochemistry.

RESULTS

Basal Cl(-) secretion and forskolin-stimulated duodenal and jejunal mucosal HCO3 (-) and Cl(-) secretions in mice with common biliary duct ligation were markedly elevated, compared with controls (P < 0.05 and P < 0.01). Further experiments showed that basal Cl(-) secretion and forskolin-stimulated duodenal and jejunal mucosal HCO3 (-) and Cl(-) secretions in mice with external bile drainage were also markedly elevated. CFTRinh -172 inhibited forskolin-stimulated HCO3 (-) and Cl(-) secretions. The mRNA and protein expression levels of CFTR and NKCC1 in the intestinal mucosa with both biliary duct ligation and external bile drainage were markedly higher than those in controls (P < 0.001). Bile acid administration restored the changes in function and expression of CFTR and NKCC1 in the intestinal mucosa.

CONCLUSION

Bile deficiency in the intestine up-regulates the expressions of intestinal mucosal CFTR and NKCC1 and enhances intestinal mucosal HCO3 (-) and Cl(-) secretion capacity, which contributes to the understanding of intestinal physiological function for patients with biliary duct obstruction.

Porphyromonas gingivalis-mediated Epithelial Cell Entry of HIV-1

HIV-1 relies on the host's cell machinery to establish a successful infection. Surface receptors, such as CD4, CCR5, and CXCR4 of T cells and macrophages, are essential for membrane fusion of HIV-1, an initiate step in viral entry. However, it is not well defined how HIV-1 infects CD4-negative mucosal epithelial cells. Here we show that there is a specific interaction between HIV-1 and an invasive oral bacterium, Porphyromonas gingivalis. We found that HIV-1 was trapped on the bacterial surface, which led to internalization of HIV-1 virions as the bacteria invaded CD4-negative epithelial cells. Both bacterial and viral DNA was detected in HeLa and TERT-2 cells exposed to the HIV-1-P. gingivalis complexes 2 hr after the initial infection but not in cells exposed to HIV-1 alone. Moreover, epithelial cell entry of HIV-1 was positively correlated with invasive activity of the P. gingivalis strains tested, even when the binding affinities of HIV-1 to these strains were similar. Finally, it was demonstrated that the viral DNA was integrated into the genome of the host epithelial cells. These results reveal a receptor-independent HIV-1 entry into epithelial cells, which may be relevant in HIV transmission in other mucosal epithelia where complex microbial communities can be found.

Neutralizing antibodies against AAV2, AAV5 and AAV8 in healthy and HIV-1-infected subjects in China: implications for gene therapy using AAV vectors

Adeno-associated viruses (AAV) have attracted attention as potential vectors for gene therapy and vaccines against several diseases, including HIV-1 infection. However, the presence of neutralizing antibodies (NAbs) after natural AAV infections inhibits their transfection in re-exposed subjects. To identify candidate AAV vectors for therapeutic or prophylactic HIV vaccines, NAbs against AAV2, AAV5 and AAV8 were screened in the sera of healthy individuals in China and 10 developed countries and an HIV-1-infected Chinese population. Seroprevalence was higher for AAV2 (96.6%) and AAV8 (82.0%) than for AAV5 (40.2%) in normal Chinese subjects. Among individuals seropositive for AAV5, >80% had low NAb titers (<1:90). The prevalence and titers of NAbs against the three AAVs were significantly higher in China than in developed countries (P<0.01). The prevalence of NAbs against AAV5 did not differ significantly between healthy and HIV-1-infected Chinese subjects (P=0.39). Co-occurrence of NAbs against AAV2, AAV5, and AAV8 was observed in the healthy population, and 15, 41, and 41% of individuals were AAV2(+), AAV2(+)/AAV8(+), and AAV2(+)/AAV5(+)/AAV8(+), respectively. Therefore, AAV5 exposure is low in healthy and HIV-1-infected populations Chinese individuals, and vectors based on AAV5 may be appropriate for human gene therapy or vaccines.

Chronic urticaria in Chinese population: a hospital-based multicenter epidemiological study

BACKGROUND

The epidemiologic profiles of chronic urticaria (CU) vary considerably among regions, and few such data are available from China.

METHODS

We performed a multicenter open questionnaire investigation about the clinical and laboratory features of CU, defined as recurrent wheals with/without angioedema lasting for ≥6 weeks, among 3027 patients.

RESULTS

Female preponderance was observed (female/male ratio, 1.46 : 1). The mean age at diagnosis was 34.7 ± 13.8 years, and the mean disease duration was 18.5 ± 46.1 months (range, 1.5-127 months). Patients were classified as having chronic spontaneous urticaria (CSU, 61.0% of patients), physical urticaria (PU, 26.2%), or other urticaria types (OU, 2.3%). Nocturnal attacks were reported by 60% of cases. The Urticaria Activity Score (UAS) in patients with CSU was 3.8 ± 1.4. The mean Dermatology Life Quality Index was 7.3 ± 3.4 (range 0-30). Induction or exacerbation of wheals with alcohol drinking was reported by 55.7% of patients. Chronic hepatitis B was less prevalent in our CU patients compared with the general Chinese population (2.7% vs 7%). Positive autologous serum skin tests (ASSTs) were observed in 66.9% of patients. Patients with positive ASST had higher UAS, greater angioedema frequencies, longer disease durations, and poorer QoL compared with patients with negative ASST (P < 0.05).

CONCLUSION

In this Chinese population, CU usually affected youth, and CSU was the most common subtype. Autoreactivity and alcohol consumption were the top two triggers for CU, whereas latent infectious and chronic inflammatory diseases were not as common as in previous reports.

Reference intervals of bone turnover markers determined by using their curve-fitting valley for adult females in China

SUMMARY

The reference values for bone turnover markers (BTMs) have a significant role in the diagnosis, monitoring, and treatment of metabolic bone disease. This study proposes that the peak value of bone mineral density and the trough value for the BTM curve can be used to determine the reference range of BTM.

INTRODUCTION

The aim of this study is to determine the reference intervals of BTMs for adult females in China with an attempt to reference the peak bone mineral density (BMD) with the corresponding BTM valley.

METHODS

This study included 546 premenopausal and 394 postmenopausal women. The levels of several BTMs were determined, and the BMD was measured using a dual-energy X-ray absorptiometry.

RESULTS

The BTMs of postmenopausal women were 17-96 % higher than premenopausal women. The change of BTM with age presented an optimal goodness-of-fit according to the cubic regression model (R (2) = 0.074-0.346, all P = 0.000). All kinds of BTM levels were positively correlated with age in premenopausal women aged 27-56 years old (r = 0.167-0.502, P = 0.023-0.000). Except for uCTX, the BTM reference value determined using a curve-fitting valley was significantly lower than the reference values for premenopausal women. The BTM reference values determined in this study were also significantly different from the reference values given by the manufacturers of the reagents used.

CONCLUSIONS

This study found that the changes of level with age of BTMs in Chinese women present an optimal goodness-of-fit according to the cubic regression model. The fitting valley corresponds to the BMD fitting peak and may possibly be an effective means of determining the BTM reference intervals.

The LIM protein fhlA is essential for heart chamber development in zebrafish embryos

Four-and-a-half LIM proteins FHL1-3 play important roles in cardiovascular pathophysiology. However, their roles in heart development remain unclear. Here, we report that fhlA, the zebrafish homolog of human FHL1, was found to be expressed around the 22-somite stage. After 24 hpf, expression was restricted to the heart. fhlA knockdown caused an enlarged cardiac chamber phenotype with up-regulated expression of the cardiac markers, but fhlA overexpression reduced the sizes of the cardiac chambers and down-regulated expression of the markers. The morphology associated with the cmlc2, amhc, and vmhc expression patterns at the 22 somite and 24 hpf stages included a broadened domain in embryos lacking fhlA and a smaller domain in embryos overexpressing fhlA. The changes in the sizes of the chambers were attributed to the changes in the number of ventricular and atrial cells. Loss of fhlA caused a longer heart period and pause between heartbeats in M-modes than in controls, but fhlA overexpression caused shorter systolic and diastolic intervals. Abnormal cardiac chambers and physiological function were found to be largely rescued. We also showed the expression of fhlA in the heart to be increased by retinoic acid (RA) and decreased by the RA synthase inhibitor DEAB. Both fhlA and RA signaling caused a phenotype characterized by the morphological alterations in the chamber sizes, suggesting that the role of fhlA in heart development is probably regulated by RA signaling. Taken together, these results showed that fhlA regulates the size of the heart chamber by reducing the number of cardiac cells.

Computational identification of miRNAs and their targets in Phaseolus vulgaris

MicroRNAs (miRNAs) are a class of non-coding small RNAs that negatively regulate gene expression at the post-transcriptional level. Although thousands of miRNAs have been identified in plants, limited information is available about miRNAs in Phaseolus vulgaris, despite it being an important food legume worldwide. The high conservation of plant miRNAs enables the identification of new miRNAs in P. vulgaris by homology analysis. Here, 1804 known and unique plant miRNAs from 37 plant species were blast-searched against expressed sequence tag and genomic survey sequence databases to identify novel miRNAs in P. vulgaris. All candidate sequences were screened by a series of miRNA filtering criteria. Finally, we identified 27 conserved miRNAs, belonging to 24 miRNA families. When compared against known miRNAs in P. vulgaris, we found that 24 of the 27 miRNAs were newly discovered. Further, we identified 92 potential target genes with known functions for these novel miRNAs. Most of these target genes were predicted to be involved in plant development, signal transduction, metabolic pathways, disease resistance, and environmental stress response. The identification of the novel miRNAs in P. vulgaris is anticipated to provide baseline information for further research about the biological functions and evolution of miRNAs in P. vulgaris.

MicroRNA-30a-3p inhibits tumor proliferation, invasiveness and metastasis and is downregulated in hepatocellular carcinoma

BACKGROUND

MicroRNAs (miRNAs) are small non-coding RNAs that regulate physiological and pathological processes by suppressing target gene expression. Altered expression of miR-30a-3p has been demonstrated in several cancers. However, little about how miR-30a-3p functions in these cancers has been reported, and the role of miR-30a-3p in hepatocellular carcinoma (HCC) is unknown. The purpose of this study was to identify the role and underlying molecular mechanism of action of miR-30a-3p in HCC.

METHODS

A total of 110 HCC patients, primarily treated by surgical removal of tumors, were involved in the study. HCC cell line Bel-7402 was selected to characterize the function of miR-30a-3p in vitro.

RESULTS

Our results showed that in 83.6% of the 110 HCC patients, expression of miR-30a-3p was significantly downregulated (P < 0.0001) in tumors compared to adjacent normal tissues. In a clinicopathological correlation analysis, downregulation of miR-30a-3p correlated with a significantly higher incidence of portal vein tumor thrombus (PVTT, P = 0.009). Moreover, miR-30a-3p markedly inhibited the invasion and migration of Bel-7402 HCC cells in vitro. Furthermore, miR-30a-3p overexpression had an inhibitory effect on cell proliferation, induced apoptosis and increased arrest of cells in the S phase. We further demonstrated that miR-30a-3p regulates HCC cell function by a mechanism involving reduced vimentin and MMP3 expression and restoration of E-cadherin expression.

CONCLUSIONS

our data suggest that miR-30a-3p is downregulated in HCC and acts as a tumor suppressor in vitro. Regulation of vimentin, E-cadherin and MMP3 by miR-30a-3p suggests a useful therapeutic strategy for tumors with reduced miR-30a-3p expression.

Peripheral immunomodulation with ginsenoside Rg1 ameliorates neuroinflammation-induced behavioral deficits in rats

Neuroinflammatory disturbances have been closely associated with depression and many other neuropsychiatric diseases. Although targeting neuroinflammatory mediators with centrally acting drugs has shown certain promise, its translation is faced with several challenges especially drug delivery and safety concerns. Here, we report that neuroinflammation-induced behavioral abnormality could be effectively attenuated with immunomodulatory agents that need not to gain brain penetration. In a rat model with intracerebral lipopolysaccharide (LPS) challenge, we validated that ginsenoside Rg1 (Rg1), a well-established anti-inflammatory agent, was unable to produce a direct action in the brain. Interestingly, peripherally restricted Rg1 could effectively attenuate the weight loss, anorexic- and depressive-like behavior as well as neurochemical disturbances associated with central LPS challenge. Biochemical assay of neuroimmune mediators in the periphery revealed that Rg1 could mitigate the deregulation of the hypothalamic-pituitary-adrenal axis and selectively blunt the increase in circulating interleukin-6 levels. Furthermore, these peripheral regulatory effects were accompanied by dampened microglial activation, mitigated expression of pro-inflammatory mediators and neurotoxic species in the central compartment. Taken together, our work suggested that targeting the peripheral immune system may serve as a novel therapeutic approach to neuroinflammation-induced neuropsychiatric disorders. Moreover, our findings provided the rationale for employing peripherally active agents like Rg1 to combat mental disturbances.

Identification of miRNAs and their targets in wheat (Triticum aestivum L.) by EST analysis

MicroRNAs (miRNAs) are a newly discovered class of noncoding small RNAs that regulate gene expression by directing target mRNA cleavage or translational inhibition. A large number of miRNAs have been identified in plants. Increasing evidence has shown that miRNAs play multiple roles in plant biological processes. So far, identification of miRNAs has been limited to a few model plant species, whose genomes have been sequenced. Wheat (Triticum aestivum L.) is one of the most important cereal crops worldwide. To date, only a few conserved miRNAs have been predicted in wheat. Here, we showed the conserved miRNAs identified in wheat by expressed sequence tag (EST) analysis. All previously known miRNAs from Arabidopsis, rice, and other plant species were used in a BLAST search against the wheat EST database to identify novel wheat miRNAs by a series of filtering criteria. By this strategy, we identified 62 conserved miRNAs, belonging to 30 miRNA families, 48 of which were newly discovered in wheat. These newly identified wheat miRNAs may regulate 287 potential targets, which are involved in development, signal transduction, metabolic pathways, disease resistance, ion transportation, and environmental stress response.

Propranolol induces apoptosis of human umbilical vein endothelial cells through downregulation of CD147

BACKGROUND

Infantile haemangiomas (IHs) are benign tumours in infancy. Most patients suffering from IHs do not require treatment. However, if there is a dramatic aesthetic or functional impairment, treatment is needed. Currently the most promising therapy for complicated IHs is the oral administration of propranolol, but its mechanism is unclear.

OBJECTIVES

To investigate the role of CD147 in propranolol-induced apoptosis in human umbilical vein endothelial cells (HUVECs).

METHODS

Human umbilical vein endothelial cells were treated with propranolol, and the treatment effects were investigated through the following methodology. (i) Cell proliferation and apoptosis were detected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometric analysis. (ii) The expression level of CD147 was measured by reverse-transcription polymerase chain reaction and Western blotting. (iii) HUVECs were transfected with lentivirus encoding CD147 short hairpin (sh)RNA or CD147 cDNA. Ensuing changes in cell proliferation and apoptosis after transfection were measured using the MTT assay and flow cytometry. (iv) The level of phosphorylation of Bcl-2-associated death promoter (BAD) at Ser112 in HUVECs after propranolol treatment and/or CD147 shRNA transfection was detected by Western blotting.

RESULTS

Propranolol inhibited cell proliferation and induced apoptosis in HUVECs. It decreased CD147 protein expression in a concentration-dependent manner. Knocking down CD147 not only induced apoptosis but also exacerbated the apoptosis triggered by propranolol in HUVECs. Overexpression of CD147 can protect HUVECs from apoptosis and propranolol-induced apoptosis. Furthermore, knockdown of both propranolol and CD147 can downregulate Ser112 phosphorylation of BAD, indicating that propranolol and CD147 induce apoptosis in HUVECs through the same signalling transduction pathway.

CONCLUSIONS

Our studies demonstrate that propranolol-induced apoptosis may be mediated through the downregulation of CD147 in HUVECs. This study highlights a novel step in propranolol action and suggests a potential new target for the treatment of IHs.

Guided bone regeneration using acellular bovine pericardium in a rabbit mandibular model: in-vitro and in-vivo studies

BACKGROUND AND OBJECTIVE

To investigate the feasibility of acellular bovine pericardium (BP) for guided bone regeneration (GBR) in vitro and in vivo. The success of GBR relies on the fact that various cellular components possess different migration rates into the defect site and that a barrier membrane plays a significant role in these processes.

MATERIAL AND METHODS

BP membrane was isolated and decellularized using an enzymatic method. The microarchitecture, mechanical properties, cytotoxicity and cell chemotaxis properties of the acellular BP were evaluated in vitro, and the in-vivo efficacy of the acellular BP was also investigated in a rabbit mandibular model.

RESULTS

The acellular BP membrane possessed an interconnected fibrous structure. Glutaraldehyde (GA) treatment was efficient for enhancement of the mechanical properties of the acellular BP bur and resulted in negligible cytotoxicity. After 16 wk, standardized osseous defects created in the rabbit mandible, and covered with acellular BP, were associated with an enhanced deposition of mineralized tissue when compared with defects left to spontaneous healing.

CONCLUSION

GA-treated acellular BP is promising as a barrier membrane for GBR for further in-vivo and clinical studies.

Early epigenetic downregulation of WNK2 kinase during pancreatic ductal adenocarcinoma development

Pancreatic ductal adenocarcinoma (PDAC) is usually incurable. Contrary to genetic mechanisms involved in PDAC pathogenesis, epigenetic alterations are ill defined. Here, we determine the contribution of epigenetically silenced genes to the development of PDAC. We analyzed enriched, highly methylated DNAs from PDACs, chronic pancreatitis (CP) and normal tissues using CpG island microarrays and identified WNK2 as a prominent candidate tumor suppressor gene being downregulated early in PDAC development. WNK2 was further investigated in tissue microarrays, methylation analysis of early pancreatic intraepithelial neoplasia (PanIN), mouse models for PDAC and pancreatitis, re-expression studies after demethylation, and cell growth assays using WNK2 overexpression. Demethylation assays confirmed the link between methylation and expression. WNK2 hypermethylation was higher in tumor than in surrounding inflamed tissues and was observed in PanIN lesions as well as in a PDAC mouse model. WNK2 mRNA and protein expressions were lower in PDAC and CP compared with normal tissues both in patients and mouse models. Overexpression of WNK2 led to reduced cell growth, and WNK2 expression in tissues correlated negatively with pERK1/2 expression, a downstream target of WNK2 responsible for cell proliferation. Downregulation of WNK2 by promoter hypermethylation occurs early in PDAC pathogenesis and may support tumor cell growth via the ERK-MAPK pathway.

Preparation and Characterization of a Phosphorous Free and Non-Nitrogen Antiscalant in Industrial Cooling Systems

A novel nonpolluting type of calcium phosphate and iron(III) antiscalant MCn was synthesized. The observation shows that MCn causes a disordered calcium phosphate. Furthermore, both calcium phosphate and iron(III) inhibition increase with increasing degree of polymerization of MCn from 5 to 13, and the dosage of MCn plays an important role on calcium phosphate and iron(III) inhibition. Inhibition mechanism is proposed the interactions between calcium or iron ions and polyethylene glycol (PEG) are the fundamental impetus to restrain the formation of the scale in cooling water systems.

Galectin-1 prolongs survival of mouse liver allografts from Flt3L-pretreated donors

Liver allografts are spontaneously accepted across MHC barriers in mice. The mechanisms underlying this phenomenon remain poorly understood. Galectin-1, an endogenous lectin expressed in lymphoid organs, plays a vital role in maintaining central and peripheral tolerance. This study was to investigate the role of galectin-1 in spontaneous tolerance of liver allografts in mice, and to evaluate the therapeutic effects of galectin-1 on liver allograft rejection induced by donor Flt3L pretreatment. Blockade of the galectin-1 pathway via neutralizing antigalectin-1 mAb did not affect survival of the liver allografts from B6 donors into C3H recipients. Administration of rGal-1 significantly prolonged survival of liver allografts from Flt3L-pretreated donors and ameliorated Flt3L-triggered liver allograft rejection. This effect was associated with increased apoptosis of T cells in both allografts and spleens, decreased frequencies of Th1 and Th17 cells, decreased expression of Th1-associated cytokines (IL-12, IL-2 and IFN-γ), Th17-associated cytokines (IL-23 and IL-17) and granzyme B, in parallel with selectively increased IL-10 expression in liver allografts. In vitro, galectin-1 inhibited Flt3L-differentiated DC-mediated proliferation of allo-CD4(+) T cells and production of IFN-γ and IL-17. These data provide new evidence of the potential regulatory effects of galectin-1 in alloimmune responses in a murine model of liver transplantation.

The role of intestinal mucosa oxidative stress in gut barrier dysfunction of severe acute pancreatitis

BACKGROUND

Severe acute pancreatitis (SAP) is a serious systemic disease with a sustained high mortality rate. Extensive evidence has shown that gut barrier dysfunction plays a critical role in the pathophysiology of SAP.

AIM

Investigating the role of intestinal mucosa oxidative stress in gut barrier dysfunction of SAP.

MATERIALS AND METHODS

Twenty-four BALB/c mice were randomly divided into two groups with twelve mice each group. The SAP group mice received six intraperitoneal injections of cerulein (50 µg/kg) at 1-hour intervals, then given one intraperitoneal injection of 10 mg/kg lipopolysaccharide (LPS from E. coli) for inducing SAP. Normal saline was given to the mice of control group. The animals of each group were averaged to two batches. Four and eight hours after the final injection, respectively, mice were anesthetized and blood and tissue samples were harvested for examination. The pathological changes of pancreas and gut were observed and scored. The serum levels of diamine oxidase (DAO), amylase and tumor necrosis factor-alpha (TNF-α) were measured. The contents of malondialdehyde (MDA) and reduced glutathione (GSH) and activity of superoxide dismutase (SOD) and xanthine oxidase (XO) in gut mucosa were detected. In gut mucosa, the caspase-3 activity was measured and the cell apoptosis and apoptosis index (AI) were determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The data were analyzed by ANOVA and t-test.

RESULTS

At four and eight hours after SAP induction, the SAP group mice had significantly higher pancreatic and gut pathological scores (p < 0.01) and increased serum levels of amylase (p < 0.05), DAO and TNF-α (p < 0.01) and increased MDA contents and XO activity of gut mucosa (p < 0.01) compared with those of control mice. There were significantly lower GSH contents (p < 0.05) and SOD activity (p < 0.01) of gut mucosa in the SAP mice. It was also observed that the gut mucosa cells of SAP mice had significantly higher caspase-3 activity and apoptosis index (p < 0.01).

CONCLUSIONS

In SAP, waterfall-style release of inflammatory factors such as TNF-α led to ischemia-reperfusion injury of gut mucosa which resulted in serious oxidative stress and activation of caspase-3 pathway and severe apoptosis of gut mucosa. Therefore, intestinal mucosal oxidative stress may play an important role in the mechanism of gut barrier dysfunction.

Syntaxin-3 regulates newcomer insulin granule exocytosis and compound fusion in pancreatic beta cells

AIMS/HYPOTHESIS

The molecular basis of the exocytosis of secretory insulin-containing granules (SGs) during biphasic glucose-stimulated insulin secretion (GSIS) from pancreatic beta cells remains unclear. Syntaxin (SYN)-1A and SYN-4 have been shown to mediate insulin exocytosis. The insulin-secretory function of SYN-3, which is particularly abundant in SGs, is unclear.

METHODS

Mouse pancreatic islets and INS-1 cells were treated with adenovirus carrying Syn-3 (also known as Stx3) or small interfering RNA targeting Syn-3 in order to examine insulin secretion by radioimmunoassay. The localisation and distribution of insulin granules were examined by confocal and electron microscopy. Dynamic single-granule fusion events were assessed using total internal reflection fluorescence microscopy (TIRFM).

RESULTS

Depletion of endogenous SYN-3 inhibited insulin release. TIRFM showed no change in the number or fusion competence of previously docked SGs but, instead, a marked reduction in the recruitment of newcomer SGs and their subsequent exocytotic fusion during biphasic GSIS. Conversely, overexpression of Syn-3 enhanced both phases of GSIS, owing to the increase in newcomer SGs and, remarkably, to increased SG-SG fusion, which was confirmed by electron microscopy.

CONCLUSIONS/INTERPRETATION

In insulin secretion, SYN-3 plays a role in the mediation of newcomer SG exocytosis and SG-SG fusion that contributes to biphasic GSIS.

Abstract PD10-09: CYP2D6 and adjuvant tamoxifen: Impact on outcome in pre- but not postmenopausal breast cancer patients

Background: The therapeutic effect of tamoxifen in adjuvant treatment of hormone receptor positive breast cancer might be impaired in patients with cytochrome P450 2D6 (CYP2D6) genotypes that predispose to decreased formation of potent anti-estrogenic tamoxifen metabolites. However, previous studies have shown inconsistent findings in this regard. In light of two recent studies failing to show an impact of CYP2D6 genotype on outcome in postmenopausal patients, we hypothesized that deficient CYP2D6 might be of greater importance in premenopausal patients with high levels of circulating estrogen. We therefore aimed to study the effect of CYP2D6 activity in both pre- and postmenopausal patients who were adherent to tamoxifen treatment for at least one year.

Methods: 382 patients, from a population-based cohort of unselected breast cancer patients that were prescribed adjuvant tamoxifen for five years, constituted the base of the study. Information on menopausal status, tumor characteristics, treatment data including compliance and outcome was retrieved from medical records. Comprehensive CYP2D6 genotyping was performed and functionally translated into constitutive, metabolic activity.

Results: In patients adherent to tamoxifen for at least one year (n = 313) there was an association of reduced CYP2D6 activity (≤50% of normal) to both recurrence (p = 0.02) and breast cancer-specific mortality (p = 0.03). In a multivariable analysis including CYP2D6 activity, age at diagnosis, tumor size, lymph node status, grade, adjuvant chemotherapy and concomitant use of CYP2D6 inhibitors, CYP2D6 remained an independent predictor of recurrence (HR = 0.39, 95% CI: 0.18–0.85, p = 0.02) and breast cancer specific survival (HR = 0.33, 95% CI 0.12–0.90, p = 0.03). Gradually decreasing CYP2D6 activity paralleled increasing risk of recurrence and breast cancer related mortality. The effect of CYP2D6 derived mainly from premenopausal patients with an association to both recurrence (p = 0.01) and breast cancer specific survival (p = 0.04). There was no such association in the postmenopausal group.

Conclusion: In a prospectively collected cohort of tamoxifen-treated breast cancer patients, an association between CYP2D6 genotype and outcome was evident in patients that were adherent to tamoxifen treatment for at least a year. Importantly, this effect derived from premenopausal patients only.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD10-09.

First Report of Root-Knot Nematode Meloidogyne arenaria Infesting Roots of Anubias barteri in Guangdong, China

Anubias spp. are very popular aquatic plants that are native to Africa. Anubias barteri is a broadleaf Anubias and is a popular choice for aquariums because of its robust size. In China, broadleaf Anubias is usually planted in sand, with sponges around the rhizome, in small plastic baskets in aquatic plant nurseries. In December 2010, a survey of phytoparasitic nematodes was conducted in the nurseries in Guangzhou, Guangdong Province. Many second-stage juveniles of a Meloidogyne sp. were detected from the roots of A. barteri, but no root galls were found. To identify these juveniles, molecular identification was performed with PCR. The DNA sequence between CO II and l-rRNA of the mitochondrial gene of single juveniles was amplified with universal primers of Meloidogyne, #C2F3 (5'-GGTCAATGTTCAGAAATTTGTGG-3') and #1108 (5'-TACCTTTGACCAATCACGCT-3') (3). The amplified fragments were approximately 1.1 kb long and could not be digested with restrictive enzyme HinfI. The specific fragments were then sequenced. The blast search result revealed that the DNA sequence (GenBank Accession No. JQ446377) had 99 to 100% identity with submitted sequences of Meloidogyne arenaria (GenBank Accession Nos. EU364879, GQ266686, and AY635610). The other extracted juveniles were inoculated into sterile, potted, water spinach (Ipomoea aquatica) in the greenhouse to obtain more nematodes. After 40 days, root galls and female egg masses were clearly observed, and biochemical, molecular, and morphological identifications were conducted. Isoenzyme phenotype (esterase and malate dehydrogenase (MDH) patterns) and the perineal pattern of several gravid females were the same as M. arenaria (1,2), and PCR amplification of single juveniles produced identical fragments as previously found. Single egg masses were collected and juveniles were hatched out and inoculated onto 10 nematode-free plants of A. barteri in a greenhouse. After 40 days, roots of A. barteri exhibited inconspicuous small galls, and the same identification procedures were conducted as mentioned previously. Isoenzyme phenotypes, perineal patterns of adult females, and amplified fragments of single juveniles were identical to those of M. arenaria. M. arenaria is one of the most important root-knot nematodes and causes great losses in many crops around the world (2). To our knowledge, this is the first record of M. arenaria parasitizing aquatic plants of broadleaf Anubias in China and elsewhere, and A. barteri is a new host of M. arenaria. The economic importance of this nematode to A. barteri production is currently unknown. However, because A. barteri is a commercial aquatic plant, more attention should be given by producers to prevent this nematode from becoming an important pathogen. In addition, this finding is very helpful for relevant plant nematode quarantine work. References: (1) P. R. Esbenshade and A. C. Triantaphyllou. J. Nematol. 17:1, 1985. (2) R. N. Perry et al. Root-Knot Nematodes. CABI. Wallingford, UK, 2009. (3) T. O. Powers and T. S. Harris. J. Nematol. 25:1, 1993.

Omentin-1 exerts bone-sparing effect in ovariectomized mice

Omentin-1 inhibited osteoblast differentiation in vitro. In co-culture systems of osteoblasts and osteoclast precursors, omentin-1 reduced osteoclast formation by stimulating osteoprotegerin (OPG) and inhibiting receptor activator for nuclear factor κB ligand (RANKL) production in osteoblasts. In vivo, adenovirus-mediated overexpression of omentin-1 suppressed bone turnover and restored bone mineral density (BMD) and bone strength in ovariectomized mice.

INTRODUCTION

Omentin-1 (also intelectin-1) is a recently identified visceral adipose tissue-derived cytokine that is highly abundant in plasma. This study was undertaken to investigate the effects of omentin-1 on bone metabolism.

METHODS

Osteoblast differentiation was assessed by measuring alkaline phosphatase activity, osteocalcin production and matrix mineralization. OPG and RANKL protein expression and secretion in osteoblasts were detected by Western blot and ELISA, respectively. The effect of recombinant omentin-1 on osteoclast formation was examined in co-culture systems of osteoblasts and osteoclast precursors. The effects of intravenous administration of adenoviral-delivered omentin-1 on bone mass, bone strength, and bone turnover were also examined in ovariectomized mice.

RESULTS

In vitro, omentin-1 inhibited osteoblast differentiation, while it had no direct effect on osteoclast differentiation; it also reduced osteoclast formation in the co-culture systems through stimulating OPG and inhibiting RANKL production in osteoblasts. In vivo, adenovirus-mediated overexpression of omentin-1 partially restored BMD and bone strength in ovariectomized mice, accompanied by decreased levels of plasma osteocalcin and tartrate-resistant acid phosphatase-5b and lower serum RANKL/OPG ratios.

CONCLUSION

The present study suggests that omentin-1 ameliorates bone loss induced by estrogen deficiency via downregulating the RANKL/OPG ratio.

Streptococcus cristatus ArcA interferes with Porphyromonas gingivalis pathogenicity in mice

BACKGROUND AND OBJECTIVE

Porphyromonas gingivalis has been implicated as one of the major pathogens in chronic periodontitis, an infectious disease affecting the majority of the adult population. We have previously demonstrated that a surface protein, arginine deiminase (ArcA), of Streptococcus cristatus represses production of P. gingivalis long fimbriae and interrupts the formation of P. gingivalis biofilms in vitro. Our in vivo studies have also shown that the distribution of P. gingivalis and S. cristatus in human subgingival plaque is negatively correlated. The objective of this study was to determine if S. cristatus ArcA inhibits P. gingivalis colonization and attenuates its subsequent pathogenesis in alveolar bone loss in the murine oral cavity.

MATERIAL AND METHODS

A wild-type strain of S. cristatus (CC5A) and its arcA knockout mutant (ArcAE) were used as initial colonizers in the oral cavity of BALB/cByJ mice. Colonization of P. gingivalis on the existing S. cristatus biofilms was assessed by quantitative PCR, and P. gingivalis-induced alveolar bone loss was measured 6 wk after P. gingivalis infection.

RESULTS

The presence of S. cristatus CC5A, but not its arcA mutant, attenuated P. gingivalis colonization in the murine oral cavity. In addition, P. gingivalis-induced alveolar bone loss was significantly lower in mice initially infected with S. cristatus CC5A than in those infected with the arcA mutant.

CONCLUSION

This study provides direct evidence that S. cristatus ArcA has an inhibitory effect on P. gingivalis colonization, which may in turn attenuate the pathogenicity of P. gingivalis.

Differential response of normal human epidermal keratinocytes and HaCaT cells to hydrogen peroxide-induced oxidative stress

BACKGROUND

  Normal human epidermal keratinocytes (NHEKs) and HaCaT cells are the most common models used to study the effects of various factors on skin cells. These cell lines share some common characteristics, but little is known about their differences in handling hydrogen peroxide (H(2) O(2) )-induced oxidative stress.

AIM

To investigate the differential response of NHEKs and HaCaT cells to H(2) O(2) -induced oxidative stress.

METHODS

We examined differences in NHEKs and HaCaT cells after H(2) O(2) treatment, assessing changes in cell viability; levels of intracellular reactive oxygen species (ROS), superoxide dismutase (SOD) and caspase-3/7; percentage of cells arrested in G1 phase; number of senescence-associated β-galactosidase (SA-β-Gal)-positive cells and; expression of senescence-related protein Klotho.

RESULTS

The viability of NHEKs and HaCaT cells decreased in a concentration-dependent and time-dependent manner after exposure to H(2) O(2) . The inhibitory effect of 150 μmol/L H(2) O(2) on cell viability was greater in HaCaT cells than in NHEKs (P<0.05). Levels of ROS and caspase-3/7, and the percentage of cells arrested in G1 phase, were higher in HaCaT cells than in NHEKs, whereas intracellular SOD was higher in NHEKs than in HaCaT cells after exposure to 150 μmol/L H(2) O(2) (P < 0.05). SA-β-Gal positive cells increased significantly in NHEKs after treatment with H(2) O(2) (P < 0.05). Klotho was significantly downregulated in both NHEKs and HaCaT cells after H(2) O(2) treatment, but no SA-β-Gal-positive HaCaT cells were seen, even after treatment with H(2) O(2) .

CONCLUSIONS

Normal human epidermal keratinocytes are more resistant than HaCaT cells to H(2) O(2) -induced oxidative stress. HaCaT cells have senescence phenotypes, but do not express β-Gal.