A critical role of thrombin/PAR-1 in ADP-induced platelet secretion and the second wave of aggregation

BACKGROUND

The stable or second wave of platelet aggregation often observed in ADP-stimulated platelet-rich plasma (PRP) with an artificially lowered extracellular calcium level has been attributed to enhanced thromboxane A2 (TXA2 ) generation and inhibition of ectonucleotidase activity. However, the role of thrombin in ADP-induced platelet secretion and the second wave of aggregation is unknown.

OBJECTIVES AND METHODS

We employed aggregometry, flow cytometry, immunoblotting and ELISA to determine whether and how thrombin participates in ADP-induced platelet secretion and the second wave of aggregation.

RESULTS

ADP induces a phosphoinositide 3-kinase (PI3K) pathway-dependent thrombin generation, presumably resulting from the cleavage of αII b β3 -associated prothrombin. Generated thrombin subsequently activates protease-activated receptor-1 (PAR-1) and mediates dense granule secretion and the second wave of platelet aggregation in ADP-stimulated citrated PRP. Thus, ADP-induced dense granule secretion and the second wave of platelet aggregation in PRP were similarly and non-additively blocked by thrombin inhibitor hirudin, PAR-1 antagonist SCH-79797 or PI3K inhibitor wortmannin. Moreover, ADP stimulation caused the dissociation of prothrombin from αII b β3 and an increased plasma thrombin level; both were prevented by wortmannin. Furthermore, the wortmannin-inhibited second wave of platelet aggregation by ADP was restored by a subaggregation concentration of PAR-1 activating peptide SFLLRN. Blocking TXA2 production with indomethacin or restoring extracellular calcium to physiological concentration did not influence this thrombin/PAR-1 dependence.

CONCLUSIONS

A PI3K-dependent thrombin generation and the resultant PAR-1 activation serve as an indispensable mechanism to relay the platelet activation process induced by ADP.

Pharmacokinetics of a new immediate-release compound omeprazole capsule and its comparison with the enteric-coated formulation under fasting and fed conditions

The present study was conducted to describe the pharmacokinetic profile of immediate-release compound omeprazole capsule and compare it with the enteric-coated formulation under fasting and fed condition.This study was designed to phase I, open-label, randomized, 3-part clinical trial. 12 subjects in part one received single doses (20 mg and 40 mg) and repeated doses (20 mg). Different 30 subjects in part 2 (fasting condition) and part 3 (fed condition) received either compound omeprazole capsule (40 mg) or delayed-release omeprazole (40 mg) separated by 7 days.Compound omeprazole capsule showed dose non-proportionality in the range from 20 mg to 40 mg. The AUC0-t of 20 mg omeprazole is 78% higher after repeated doses. The C max was higher and T max was lower for compound omeprazole capsule than delayed-release omeprazole. 90% CIs for AUC0-t of the 2 periods (test/reference) under fasting and fed conditions were 106.3% (102.2%~109.2%) and 104.1% (93.4%~109.6%), respectively. Presence of food reduced the rate (C max) and extent (AUC0-t) of systemic exposure of the test and reference formulations from 1 462 to 777 ng · mL-1, 1 055 to 602 ng · mL-1, 2 597 to 1 852 ng · h · mL-1 and 2 454 to 1 873 ng · h · mL-1, respectively.Exposed dose of omeprazole in subjects with compound omeprazole capsule was time- and dose-dependent. Compared with delayed-release omeprazole, compound omeprazole capsule had rapid but similar degree of absorption of omeprazole.

Aberrant intrinsic brain activity and cognitive deficit in first-episode treatment-naive patients with schizophrenia

BACKGROUND

Given the important role of the default mode network (DMN) in cognitive function and the well-known neurocognitive deficit in schizophrenia, it is intriguing to examine systematically the relationship between neurocognitive dysfunction and aberrant intrinsic activities, and also functional connectivity, of the DMN in patients with schizophrenia. Method First-episode, treatment-naive patients with schizophrenia (FES) (n = 115) and healthy controls (n = 113) underwent resting-state functional magnetic resonance imaging (fMRI) scans and neurocognitive tests. Intrinsic neural activities evaluated by using the fragment amplitude of low-frequency fluctuations (fALFF) and the resting-state functional connectivity assessed by seed-based correlational analysis were compared between patients and controls. Aberrant intrinsic activities and DMN connectivity in patients were then correlated to neurocognitive performance and clinical symptoms.

RESULTS

Compared to controls, patients with FES showed decreased fALFF in the bilateral medial prefrontal cortex (MPFC) and the orbitofrontal cortex (OFC), and increased fALFF in the bilateral putamen. Increased functional connectivity with the DMN was observed in the left insula and bilateral dorsolateral PFC (DLPFC) in patients with FES. In patients, aberrant fALFF in the bilateral OFC were correlated with cognitive processing speed; fALFF in the left OFC and right putamen were correlated with the clinical factors excited/activation and disorganization; and increased DMN functional connectivity in the left insula was correlated with the clinical factors positive, excited/activation, disorganization and neurocognitive deficit in the domain of sustained attention.

CONCLUSIONS

These associations between neurocognitive dysfunction and aberrant intrinsic activities, and also functional connectivity, of the DMN in patients with schizophrenia may provide important insights into the neural mechanism of the disease.

Etiology of Moldy Core, Core Browning, and Core Rot of Fuji Apple in China

'Fuji' apple fruit were collected in Shaanxi Province, China, and 186 fungal isolates were obtained from the fruit core region. Fungi were isolated from fruit with symptomless core regions, as well as from the core regions of fruit showing browning, typical moldy core, or core rot. Based on phylogenetic and morphological analysis, all fungi were identified to species. Pathogenicity was determined by cutting apple fruit into halves and daubing spore suspensions containing 1 × 10⁴ up to 1 × 10⁸ spores/ml on the carpel in the core region. Pathogenicity varied significantly among genera, with Alternaria and Cladosporium spp. causing core browning at lower spore concentrations and moldy core at higher spore concentrations. Combinations of pathogens initiated more browning and moldy core than the pathogens applied alone. Epicoccum and Phoma spp. predominated in dry core rot, whereas primarily Trichothecium but also Fusarium and Penicillium spp. caused wet core rot. Core browning was introduced as a new type of core symptom, along with moldy core, dry core rot, and wet core rot. Alternaria alternata, A. tenuissima, A. arborescens, Cladosporium cladosporioides, and C. tenuissimum were the main pathogens causing core browning and moldy core.

Focal dermal hypoplasia: updates

Focal dermal hypoplasia (FDH), or Goltz-Gorlin syndrome, is a rare syndrome and may result in multisystem disorders. Several reviews of FDH have been published. However, the last comprehensive review of this disorder appeared more than 20 years ago. To date, a number of new clinical manifestations have been reported and considerable knowledge has accumulated regarding etiology and pathogenetic mechanisms. The purpose of this review is to gather these more recent data and to provide organized and reliable information. So we reviewed 159 cases of FDH that had been reported from 1990 to 2012, summarized the new discoveries, and suggested a potential standard for the diagnosis of FDH. We also reported on a Chinese girl with FDH, who was clinically and histologically in accord with FDH, as an example.

Choice of microsatellite markers for identifying homozygosity of mitotic gynogenetic diploids in Japanese flounder Paralichthys olivaceus

A set of 72 microsatellite markers distributed evenly among 24 linkage groups were selected from the published genetic linkage maps of Japanese flounder Paralichthys olivaceus. In two normal diploid full-sib families, the test for Mendelian inheritance showed that genotypic segregation deviations were not significant at all analysed loci. To estimate microsatellite-centromere map distances, four meiotic gynogenetic diploid lines were produced by the activation of eggs using UV irradiated sperm of red seabream Pagrus major and cold-shock treatment to block the extrusion of the second polar body. Under the assumption of complete interference, 21 markers were located in the centromeric region, 39 in the telomeric region and the rest in the intermediate region of linkage groups. A total of 192 mitotic gynogenetic diploids from one spawn were identified by these markers. Genotype analysis showed that the number of homozygous individuals decreased as microsatellite-centromere map distance increased on each linkage group.

Establishment of Eimeria tenella (local isolate) in chicken embryos

Development of an in vitro Eimeria (E.) tenella model could be valuable as a tool for vaccine, coccidiostats or molecular biology research. 1.0 × 10,000 sporozoites per 0.1 mL were inoculated into the allantoic cavity of ten-day-old chicken embryos. The complete life-cycle of E. tenella was accomplished in eight-nine days at 37 °C and 70% humidity. The addition of 100 U insulin to the embryos could remarkably improve the output of oocysts. The development of the parasite within the embryos was systematically observed, allowing guidelines to be set regarding the appropriate times at which different developmental stages of the parasite may be sampled.

Association between lysyl oxidase G473A polymorphism and ovarian cancer in the Han Chinese population

OBJECTIVE

Lysyl oxidase (LOX) is an extracellular enzyme critical for the cross-linking of collagens and elastin. A single-nucleotide polymorphism of LOX G473A is associated with various diseases. This retrospective study investigated the association between LOX G473A polymorphism and susceptibility to ovarian cancer in the Han Chinese population.

METHODS

The LOX variant G473A was detected by polymerase chain reaction-restriction fragment length polymorphism in patients with ovarian cancer and healthy control subjects.

RESULTS

The frequencies of the LOX 473AA genotype and the A allele were significantly higher in patients with ovarian cancer (n = 318) than in control subjects (n = 406) (odds ratio [OR] 2.30, 95% confidence interval [CI] 1.36, 3.87; OR 1.57, 95% CI 1.23, 2.00; respectively). The prevalence of the GA genotype, AA genotype and A allele were significantly higher in patients with more advanced stages of ovarian cancer compared with those with primary stage disease.

CONCLUSIONS

This study suggests that LOX G473A polymorphism is a new risk factor for ovarian cancer and that LOX protein might be a possible therapeutic target in ovarian cancer.

Primary genome scan for complex body shape-related traits in the common carp Cyprinus carpio

To identify quantitative trait loci (QTL) that affect body shape in common carp Cyprinus carpio, a linkage map, 2159·23 cM long, was constructed with a total of 307 markers covering 51 linkage groups (LG). The map included 167 new single nucleotide polymorphism (SNP) markers derived from expressed sequence tags (EST) together with 140 microsatellite markers reported earlier. A primary genome scan was conducted for QTL for standard length (L(S)), head length (L(H)), body height (H(B)), body width (W(B)) and tail length (L(TAIL)) in an F1 line containing 92 offspring. A total of 15 suggestive QTL on six LGs were found to associate with L(S), L(H), H(B), W(B) and L(TAIL) which explained 10·7-17·4% of the variance. Five significant QTL were detected for body-shape related traits and located for LGs (lg1, 12 and 20). These QTL included: one associated with L(S) (21·1% variance explained), three for H(B) (almost 20% variance explained) and one for W(B) (20·7% variance explained).

Coherent anti-Stokes Raman scattering and spontaneous Raman spectroscopy and microscopy of microalgae with nitrogen depletion

Microalgae are extensively researched as potential feedstocks for biofuel production. Energy-rich compounds in microalgae, such as lipids, require efficient characterization techniques to investigate the metabolic pathways and the environmental factors influencing their accumulation. The model green alga Coccomyxa accumulates significant amounts of triacylglycerols (TAGs) under nitrogen depletion (N-depletion). To monitor the growth of TAGs (lipid) in microalgal cells, a study of microalgal cells (Coccomyxa sp. C169) using both spontaneous Raman and coherent anti-Stokes Raman scattering (CARS) spectroscopy and microscopy were carried out. Spontaneous Raman spectroscopy was conducted to analyze the components in the algal cells, while CARS was carried out to monitor the distribution of lipid droplets in the cells. Raman signals of carotenoid are greater in control microalgae compared to N-depleted cells. Raman signals of lipid droplets appear after N-depletion and its distribution can be clearly observed in the CARS microscopy. Both spontaneous Raman spectroscopy and CARS microscopy were found to be suitable analysis tools for microalgae.

β-Cell preservation and regeneration in diabetes by modulation of β-cell Ca²⁺ homeostasis

Ca(2+) extrusion from the β-cell is mediated by two processes the Na/Ca exchanger (NCX) and the plasma membrane Ca(2+) -ATPase (PMCA). Gain of function studies show that overexpression of NCX or PMCA leads to endoplasmic reticulum (ER) Ca(2+) depletion with subsequent ER stress, decrease in β-cell proliferation and β-cell death by apoptosis. Interestingly, chronic exposure to cytokines or high free fatty acid concentrations also induce ER Ca(2+) depletion and β-cell death in diabetes. Loss of function studies show, on the contrary, that heterozygous inactivation of NCX1 (Ncx1(+/-)) leads to an increase in β-cell function (insulin production and release), and a fivefold increase in both β-cell mass and proliferation. The mutation also increases β-cell resistance to hypoxia, and Ncx1(+/-) islets show a two to four times higher rate of diabetes cure than Ncx1(+/+) islets when transplanted in diabetic animals. Thus, down-regulation of the Na/Ca exchanger leads to various changes in β-cell function that are opposite to the major abnormalities seen in diabetes. This provides a unique model for the prevention and treatment of β-cell dysfunction in diabetes and following islet transplantation.

The association between RhEPO and FN expression in glomerular mesangial cells

AIM

Erythropoietin (rhEPO) is increasingly being used in the treatment of anemia caused by miscellaneous reasons. The aim of our research is to investigate the effects of recombinant human erythropoietin (rhEPO) on cellular growth and fibronectin (FN) expression in glomerular mesangial cells.

METHODS

Western blot was used to detect the expression of FN induced by rhEPO (1, 10, 100 and 1000U/mL). In vivo studies, male CD-1 mice were administered rhEPO subcutaneously at a single dose of 1000U/Kg. The cellular hypertrophy was quantified by counting cell number and calculating the ratio of cell protein to cell number.

RESULTS

1) Compared with the control group, the results of mesangial cells' growth stimulated by rhEPO were not significantly different; 2) RhEPO lead to hypertrophy of mesangial cells; 3) rhEPO induced FN expression of mesangial cell in a dose-dependent way. Compared to control, 100U/mL rhEPO enhanced the expression of FN significantly; 4) indirect immunofluorescence showed that rhEPO induced large amount deposition of FN in the intercellular space of mesangial cells; 5) in vivo studies, there were markedly increase of FN expression in mice received the injection of rhEPO.

CONCLUSION

RhEPO could up-regulated the expression of FN and induced glomerular mesangial cells hypertrophy. These results suggested rhEPO could induce dysfunction of renal glomerulus through its influence on the function of mesangial cells.

Combined use of etanercept and MTX restores CD4⁺/CD8⁺ ratio and Tregs in spleen and thymus in collagen-induced arthritis

OBJECTIVE

To further explore the mechanism of etanercept (ENT, rhTNFR:Fc) and methotrexate (MTX) in the combined treatment of rheumatoid arthritis (RA), we investigated whether thymic and splenic T-cell subsets and their related cytokines imbalance could be restored by ETN/MTX treatment.

METHODS

The effect of ETN/MTX on collagen-induced arthritis (CIA) was evaluated by arthritis scores, joint and spleen histopathology, as well as indices of thymus and spleen. T lymphocytes proliferation was determined by [(3)H]-TdR incorporation. Levels of TNF-α, LT-α, IL-1β, RANKL, IL-10, IL-17, IFN-γ and IL-6 were detected by enzyme linked immunosorbent assay. The subsets of T lymphocytes including CD4(+), CD8(+), CD3(+)CD4(+), CD4(+)CD25(+), CD4(+)CD62L(+) and CD4(+)CD25(+)Foxp3(+) cells were quantified using flow cytometry.

RESULTS

Combined administration of ETN/MTX significantly inhibited the proliferation of T lymphocytes, decreased serum IL-6, TNF-α, IL-1β, RANKL and macrophage supernatant IL-17, LT-α, increased serum IFN-γ and macrophage supernatant IL-10. Moreover, the combined administration could restore CD4(+)/CD8(+) ratio and Treg cells of CIA thymus and spleen.

CONCLUSION

Taken together, our findings suggest that ENT/MTX may modify the abnormal T lymphocytes balance from central to peripheral lymphoid organs, which may partially, explained the mechanism of the combined administration.

Volume increases in putamen associated with positive symptom reduction in previously drug-naive schizophrenia after 6 weeks antipsychotic treatment

BACKGROUND

Brain structure appears to alter after antipsychotic administration, but it is unknown whether these alterations are associated with improvement of psychopathology in patients with schizophrenia. In this study, the authors explore this relationship.

METHOD

Altogether, 66 first-episode, drug-naive patients with schizophrenia and 23 well-matched healthy controls underwent brain magnetic resonance imaging scans at baseline. All 23 healthy controls and 42 of the patients were rescanned after 6 weeks follow-up. The patients received regular antipsychotic treatment during the 6-week period and their psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS) at baseline and 6 weeks. The difference in PANSS scores between baseline and 6 weeks was expressed as a ratio of the scores at baseline - 'PANSS reduction ratio'. A modified tensor-based morphometry procedure was applied to analyse longitudinal images. Correlations between regional volume changes, PANSS reduction ratio and antipsychotic drug dosages were explored.

RESULTS

Compared with healthy controls, there was a significant increase in grey-matter volume of the right putamen in patients after 6 weeks treatment. This volume change was positively correlated with a positive PANSS reduction score but not related to drug dosages.

CONCLUSIONS

Putaminal volume increased after 6 weeks antipsychotic treatment in first-episode schizophrenia. The increased volume was closely correlated with improved psychopathology, suggesting the putamen might be a biomarker to predict the treatment response in schizophrenia.

SU-E-J-127: An Initial Application of Evaluating Lung Tumor Motion Throughout Radiotherapy

PURPOSE

We present a novel method for evaluating lung tumor motion incorporating planning CT scan, imaging for patient localization, and during treatment delivery.

METHODS

Tumor motion is evaluated at three stages of the treatment process. Following the acquisition of 4D CT scans for treatment planning, tumors are contoured at one phase and registered to other phases to obtain tumor motion patterns. Tumor motion prior to each treatment is evaluated by identifying tumors directly on every raw projection of the daily localization CBCT scans. Finally, tumor motion during treatment is evaluated by analyzing MV treatment beam images. Every frame of image is evaluated as three components, each with separate DRRs: all non-moving structures, the tumor, and other moving structures. The locations of three components are determined though a registration process. In order to quantify tumor motion, the cumulated probability, the percentage of time when the tumor motion is equal to or smaller than a given range, is evaluated at every stage.

RESULTS

This methodology has been applied to five lung cancer patients undergoing radiotherapy. More than 5400 frames from MV treatment beam images and 24 CBCT scans were acquired from 12 fractions. Both the average tumor position and the cumulated probability with the range were evaluated. The tumor motion ranges are generally larger than those obtained from 4D CT. Significant variation in motion patterns was observed as well.

CONCLUSIONS

Information obtained from 4DCT is insufficient for motion assessment. In contrast, our novel methodology is capable of accurately characterizing lung tumor motion on a daily basis, without the need for implanted fiducial markers and without additional imaging dose. It provides daily verification that the tumor range is within prior estimates and covered by the treatment planning volume. This research is supported by CPRIT Individual Investigator Award RP110329.