Pulsus paradoxus is an exaggeration of the normal inspiratory decrease in systolic blood pressure. Despite a century of attempts to explain this sign consensus is still lacking. To solve the controversy and reveal the exact mechanism, we reexamined the characteristic anatomic arrangement of the circulation system in the chest and designed these mechanical models based on related hydromechanic principles. Model 1 was designed to observe the primary influence of respiratory intrathoracic pressure change (RIPC) on systemic and pulmonary venous return systems (SVR and PVR) respectively. Model 2, as an equivalent mechanical model of septal swing, was to study the secondary influence of RIPC on the motion of the interventriclar septum (IVS), which might be the direct cause for pulsus paradoxus. Model 1 demonstrated that the simulated RIPC had different influence on the simulated SVR and PVR. It increased the volume of the simulated right ventricle (SRV) when the internal pressure was kept constant (8.16 cmH2O), while it had the opposite effect on PVR. Model 2 revealed the three major factors determining the respiratory displacement of IVS in normal and different pathophysiological conditions: the magnitude of RIPC, the pressure difference between the two ventricles and the intrapericardial pressure. Our models demonstrate that the different anatomical arrangement of the two venous return systems leads to a different effect of RIPC on right and left ventricles, and thus a pressure gradient across IVS that tends to shift IVS left- and rightwards. When the leftward displacement of IVS reaches a considerable amplitude in some pathologic condition such as cardiac tamponade, the pulsus paradoxus occurs.
doi:10.1371/journal.pone.0057512
PMCID: PMC3585346
PMID: 23469010
MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression by targeting the mRNAs of hundreds of human genes. Variations in miRNA expression levels were shown to be associated with glioma. We have previously found miR-30a-5p overexpression in glioma cell lines and specimens. Bioinformatics analyses predict that several miRNAs, including miR-30a-5p, are involved in the post-transcriptional regulation of SEPT7. SEPT7 is a member of the septin family, which is a highly conserved subfamily of GTPases implicated in exocytosis, apoptosis, synaptogenesis, neurodegeneration and tumorigenesis. Our previous study has also demonstrated that SEPT7 expression is decreased in astrocytic gliomas with different grades and plays a tumor suppressor role. In the present study, we knocked down miR-30a-5p with antisense oligonucleotide (miR-30a-5p AS) in LN229 and SNB19 glioblastoma(GBM) cells, and found that cell growth and invasion were inhibited, while apoptosis was induced. miR-30a-5p AS treated cells showed upregulation of SEPT7 and downregulation of PCNA, cyclin D1, Bcl2, MMP2 and MMP9. In contrast, when miR-30a-5p mimics were transfected into LN229 and SNB19 GBM cells, cell growth and invasion were promoted and the expression of relevant proteins increased. Meanwhile, the effect of miR-30a-5p mimics on glioma cells can be reversed by transfection of SEPT7 construct. Additionaly, miR-30a-5p directly targeting SEPT7 was identified by the reporter gene assay. Our study demonstrates,for the first time, that miR-30a-5p is a bona fide negative regulator of SEPT7 and the oncogenic activity of miR-30a-5p in human gliomas is at least in part through the repression of SEPT7.
doi:10.1371/journal.pone.0055008
PMCID: PMC3557229
PMID: 23383034
Iterative image reconstruction algorithms for optoacoustic tomography (OAT), also known as photoacoustic tomography, have the ability to improve image quality over analytic algorithms due to their ability to incorporate accurate models of the imaging physics, instrument response, and measurement noise. However, to date, there have been few reported attempts to employ advanced iterative image reconstruction algorithms for improving image quality in three-dimensional (3D) OAT. In this work, we implement and investigate two iterative image reconstruction methods for use with a 3D OAT small animal imager: namely, a penalized least-squares (PLS) method employing a quadratic smoothness penalty and a PLS method employing a total variation norm penalty. The reconstruction algorithms employ accurate models of the ultrasonic transducer impulse responses. Experimental data sets are employed to compare the performances of the iterative reconstruction algorithms to that of a 3D filtered backprojection (FBP) algorithm. By use of quantitative measures of image quality, we demonstrate that the iterative reconstruction algorithms can mitigate image artifacts and preserve spatial resolution more effectively than FBP algorithms. These features suggest that the use of advanced image reconstruction algorithms can improve the effectiveness of 3D OAT while reducing the amount of data required for biomedical applications.
doi:10.1088/0031-9155/57/17/5399
PMCID: PMC3532927
PMID: 22864062
Background
Although the clinical outcome of acute myocardial infarction (AMI) in patients with type 2 diabetes mellitus (T2DM) is well established to be worse than for non-diabetic patients, the reasons for this remain unclear. We hypothesized that this may be related to impairment of bone marrow-derived endothelial progenitor cells (EPCs) mobilization.
Methodology/Principal Findings
We observed short term bone marrow EPCs mobilization and long term clinical outcomes in 62 AMI patients with or without T2DM and investigated EPCs levels as well as bone marrow pathway changes in a rat model of diabetes after AMI. Patients with T2DM exhibited a delay (peak time diabetics vs. non-diabetics: day 7 vs. day 5) and a decrease in EPCs mobilization (diabetics vs. non-diabetics: 285±56/106 mononuclear cells (MNCs) vs. 431±88/106 MNCs, p<0.05) within one month after AMI. Plasma levels of VEGF and SDF-1α as well as of hsCRP were higher in T2DM patients. Over a mean of 2.26 years follow-up, T2DM patients exhibited a pronounced decrease in LVEF as well as an increase in clinical events. Glucose (HR 2.01, 95% CI 1.42–2.85, p = 0.008), first day EPC (HR 0.974, 95% CI 0.952–0.997, p = 0.02) and seven day EPCs (HR 0.966, 95% CI 0.945–0.988, p = 0.003) were independent prognostic variables for cardiovascular mortality. In a diabetic rat model of AMI, decreased circulating EPCs was accompanied by lower expression of phospho-Akt, phospho-eNOS, HIF, MMP-9 and MMP-9 activity in the bone marrow as well as impaired cardiac function, angiogenesis and increased left ventricle remodeling.
Conclusions/Significance
Bone marrow EPCs mobilization is delayed and reduced in diabetes, with impaired HIF/p-Akt/p-eNOS/MMP-9 signaling. This is likely to contribute to the deterioration in cardiac function and worsened clinical outcome seen in patients with T2DM.
doi:10.1371/journal.pone.0050739
PMCID: PMC3511359
PMID: 23226370
Sovari, Ali A. | Iravanian, Shahriar | Dolmatova, Elena | Jiao, Zhe | Liu, Hong | Zandieh, Shadi | Kumar, Vibhash | Wang, Kun | Bernstein, Kenneth E. | Bonini, Marcelo G. | Duffy, Heather | Dudley, Samuel C.
Objectives
We sought to test whether c-Src tyrosine kinase mediates connexin 43 (Cx43) reduction and sudden cardiac death in a transgenic mouse model of cardiac-restricted overexpression of angiotensin-converting enzyme (ACE8/8).
Background
Renin-angiotensin system (RAS) activation is associated with an increased risk of arrhythmia and sudden cardiac death; however, that mechanism is not well understood. The upregulation of c-Src by angiotensin II may result in the reduction of Cx43, which impairs gap junction function and provides a substrate for arrhythmia.
Method
Wild-type and ACE8/8 mice with and without treatment with the c-Src inhibitor PP1 were studied. Telemetry monitoring, in vivo electrophysiology studies, Western blot analyses for total and phosphorylated c-Src and Cx43, immunohistochemistry staining for Cx43, and functional assessment of Cx43 with fluorescent dye diffusion were performed.
Results
The majority of the arrhythmic deaths resulted from ventricular tachycardia denegerating to ventricular fibrillation (83%). Levels of total and phosphorylated c-Src were increased and Cx43 reduced in ACE8/8 mice. PP1 reduced total and phospho c-Src levels, increased the Cx43 level by 2.1-fold (P < 0.005), increased Cx43 at the gap junctions (immunostaining), improved gap junctional communication (dye spread), and reduced ventricular tachycardia inducibility and sudden cardiac death. The survival rate increased from 11% to 86% with four weeks of PP1 treatment (P < 0.005). Treatment with an inactive analog did not change survival or Cx43 levels.
Conclusion
RAS activation is associated with c-Src upregulation, Cx43 loss, reduced myocyte coupling, and arrhythmic sudden death, which can be prevented by c-Src inhibition. This suggests that an increase in c-Src activity may help mediate RAS-induced arrhythmias and that c-Src inhibitors might exert antiarrhythmic activity.
doi:10.1016/j.jacc.2011.07.048
PMCID: PMC3226807
PMID: 22093512
Angiotensin II; c-Src tyrosine kinase; connexin43; sudden cardiac death
Background
To compare the characteristics between 22-channel water-perfusion manometry (WPM) and solid-state manometry (SSM) with 36 sensors of the pressure measurements, as well as patients’ discomfort indices in nose and pharynx, the preparation and operation time of the manometry.
Methods
12 volunteers were included in the study. Each of the volunteers underwent esophageal manometry by both 22-channel water-perfusion catheter (WPC) and solid-state catheter (SSC) with 36 sensors in random order, and separated by 30 min. The subjects gave a VAS score soon after each test. Non-parametric tests were used to analyze the differences and Bland-Altman plots were used to assess the consistency of the two systems.
Results
During the wet swallows, there were significant differences between the two systems in three measurements of location of lower esophageal sphincter (LES) upper margin (Z = -2.11, P = 0.035), LES relax ratio (Z = -2.20, P = 0.028) and IRP4s (Z = -2.05, P = 0.041). During the jelly pocket swallows, LES relax ratio measurements of the two systems showed significant differences (Z = -2.805, P = 0.005). Further Bland–Altman plots analysis presented good agreement between the two systems measurements of location of LES upper margin, LES relax ratio and IRP4s. The discomfort indices of subjects’ nasal sensation were higher when inserting the solid-state catheter [5(3.75-5)] than water-perfusion one (2.5(2-4)) (Z = -2.471, P = 0.013), as well as the discomfort indices of pharyngeal sensation (7.5(4.75-9) vs. 4.5(3.75-6.5)), (Z = -2.354, P = 0.019). The preparation time for WPC was 40(39-41) minutes, which was much longer than that for SSC 32.5(31.75-33) minutes, (Z = -3.087, P = 0.002). And the nurses reported it’s much easier to insert WPC (Z = -3.126, P = 0.002).
Conclusions
In conclusion, most pressure measurements were consistent between WPM and SSM. Patients tolerated better with WPC, while for operators, the SSC presented more convenient.
doi:10.1186/1471-230X-12-157
PMCID: PMC3503791
PMID: 23134719
22-channel water-perfusion manometry; Solid-state manometry (SSM) with 36 sensors; Pressure measurements; Patients’ tolerance; Operators’ convenience; Comparative study
Background
The yak (Bos grunniens) is a long-haired bovine that lives at high altitudes and is an important source of milk, meat, fiber and fuel. The recent sequencing, assembly and annotation of its genome are expected to further our understanding of the means by which it has adapted to life at high altitudes and its ecologically important traits.
Description
The Yak Genome Database (YGD) is an internet-based resource that provides access to genomic sequence data and predicted functional information concerning the genes and proteins of Bos grunniens. The curated data stored in the YGD includes genome sequences, predicted genes and associated annotations, non-coding RNA sequences, transposable elements, single nucleotide variants, and three-way whole-genome alignments between human, cattle and yak. YGD offers useful searching and data mining tools, including the ability to search for genes by name or using function keywords as well as GBrowse genome browsers and/or BLAST servers, which can be used to visualize genome regions and identify similar sequences. Sequence data from the YGD can also be downloaded to perform local searches.
Conclusions
A new yak genome database (YGD) has been developed to facilitate studies on high-altitude adaption and bovine genomics. The database will be continuously updated to incorporate new information such as transcriptome data and population resequencing data. The YGD can be accessed at http://me.lzu.edu.cn/yak.
doi:10.1186/1471-2164-13-600
PMCID: PMC3507758
PMID: 23134687
Yak genome; Genome database; High-altitude adaption; Bovine genomics
Background
Liriodendron chinense (L. chinense) is an endangered basal angiosperm plant in China because of its low reproductive efficiency. Recently, miRNAs have obtained great attention because they can play important roles. Through high throughput sequencing technique, large amount of miRNAs were identified from different plant species. But there were few studies about the miRNAs in the basal angiosperms especially in the sexual reproduction process.
Results
Deep sequencing technology was applied to discover miRNAs in L. chinense flowers at different stages. After bioinformatic analysis, 496 putative conserved miRNAs representing 97 families and 2 novel miRNAs were found. Among them, one is previously regarded as gymnosperm specific. Their expressions were further validated by Real-time PCR for 13 selected miRNAs. Putative targeting genes were predicted and categorized with gene ontology (GO) analysis. About ten percents of the targets are involved in the reproduction process. Further expressional analysis showed that many of these miRNAs were highly related to the reproductive growth.
Conclusions
This is the first comprehensive identification of conserved and novel miRNAs in L. chinense. The data presented here might not only help to fill the gap of miRNA registered about basal angiosperm plants but also contribute to understanding the evolution of miRNAs. The differential expression of some of the miRNAs and the prediction of their target genes are also helpful in understanding the regulation of L. chinense sexual reproduction.
doi:10.1371/journal.pone.0044696
PMCID: PMC3445533
PMID: 23028583
Background
Vertebral artery dissection (VAD) is often associated with trauma or occurs spontaneously, inevitably causing some neurological deficits. Even though acute infection can be related to the development of spontaneous VAD (sVAD), VAD associated with viral meningitis has never been reported in the literature.
Case presentation
A 42-year-old man with fever, sore throat, and runny nose developed sudden onset of occipital headache, vertigo, transient confusion, diplopia, and ataxia. Brain stem encephalitis was diagnosed initially because the cerebrospinal fluid (CSF) study showed inflammatory changes. However, subsequent diffusion-weighted (DWI) magnetic resonance imaging of his brain demonstrated left lateral medullary infarction, and the digital subtraction angiography (DSA) confirmed VAD involving left V4 segment of the artery. Consequently, the patient was diagnosed as VAD accompanied by viral meningitis.
Conclusion
This case suggests that viral meningitis might lead to inflammatory injury of the vertebral arterial wall, even sVAD with multiple neurological symptoms.
doi:10.1186/1471-2377-12-79
PMCID: PMC3466159
PMID: 22909191
Vertebral artery dissection; Cerebral ischemia; Viral meningitis; Infection
In traditional Chinese medicine (TCM), diagnosis of pathology and choice of treatment prescriptions are based on a method of differentiation of signs and symptoms known as syndrome differentiation or ZHENG. The cornerstone of TCM, ZHENG, relies on the gathering of clinical information through inspection, auscultation and olfaction, inquiry, and palpation. However, the biomolecular basis of the ZHENG remains unclear. In this study, we established mouse xenograft pancreatic cancer models with Shi-Re (Dampness-Heat), Pi-Xu (Spleen-Deficiency), or Xue-Yu (Blood-Stasis) ZHENG, which are regarded as the three major ZHENGs in pancreatic cancer. We found that tumors of the different ZHENG models exhibited significantly altered cancer-associated fibroblast (CAF) proliferative activity and tumor-associated macrophage (TAM) infiltration, which led to altered levels of CAF- and TAM-derived secreted cytokines such as SDF-1 and CCL5. The ZHENG model type also significantly influenced tumor growth, and administration of herbal medicine to the ZHENG model modified the tumor microenvironment. Therefore, this study partially unveiled the molecular basis of TCM ZHENG in pancreatic cancer.
doi:10.1155/2012/635702
PMCID: PMC3368347
PMID: 22690248
Zheng, Jing-Quan | Wang, Kun | Pei, Dee | Chen, Yen-Lin | Chang, Yen-Lin | Hsu, Chun-Hsien | Huang, Tsan-Ming | Lin, Mei-Yu | Lin, Pao-Ying | Lin, Jiunn-Diann
Objectives:
Insulin resistance is one of the important underlying abnormalities of type 2 diabetes. The effect of thiazolidinedione on liver functions has been controversial in different studies. In this study, we evaluated the effect of rosiglitazone on liver enzymes in subjects with type 2 diabetes with and without abnormal liver function.
Materials and Methods:
Seventy-three patients with type 2 diabetes taking rosiglitazone 4 mg daily were enrolled in this 3-month study. Forty-two of them had normal liver function (NLF), and 31 had abnormal liver function (ABLF). Blood biochemistries were collected monthly during the treatment period.
Results:
At baseline, other than age and liver enzymes, there were no differences in body mass index, fasting plasma glucose, hemoglobin A1c (HbA1c), and lipid profiles between the NLF and ABLF groups. At the end of the treatment, HbA1c was lowered in both groups, but only significantly in the ABLF group (P = 0.027). More importantly, serum concentrations of both aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the ABLF group decreased significantly (AST: 57.8 ± 26.5 to 47.5 ± 20.2 U/L, P = 0.006; ALT 66.6 ± 35.0 to 51.9 ± 23.5 UL, P = 0.004), while in the NLF group, a similar change was not found.
Conclusion:
After 3-month rosiglitazone treatment in subjects with type 2 diabetes with mildly elevated liver enzymes, significant improvement in AST and ALT were observed. Our study provides some hints that rosiglitazone might not be contraindicated in subjects with diabetes with abnormal liver function as previously thought, but further well-designed studies are necessary to clarify this issue.
doi:10.4103/0253-7613.96340
PMCID: PMC3371462
PMID: 22701249
Rosiglitazone; type 2 diabetes; liver function
Wang, Kun | Bodempudi, Vidya | Liu, Zhengian | Borrego-Diaz, Emma | Yamoutpoor, Farnaz | Meyer, Anna | Woo, Richard A. | Pan, Weihong | Dudek, Arkadiusz Z. | Olyaee, Mojtaba S. | Esfandyari, Tuba | Farassati, Faris | Zhang, Lin
Mesothelin, a differentiation antigen present in a series of malignancies such as mesothelioma, ovarian, lung and pancreatic cancer, has been studied as a marker for diagnosis and a target for immunotherapy. We, however, were interested in evaluating the effects of direct targeting of Mesothelin on the viability of cancer cells as the first step towards developing a novel therapeutic strategy. We report here that gene specific silencing for Mesothelin by distinct methods (siRNA and microRNA) decreased viability of cancer cells from different origins such as mesothelioma (H2373), ovarian cancer (Skov3 and Ovcar-5) and pancreatic cancer (Miapaca2 and Panc-1). Additionally, the invasiveness of cancer cells was also significantly decreased upon such treatment. We then investigated pro-oncogenic signaling characteristics of cells upon mesothelin-silencing which revealed a significant decrease in phospho-ERK1 and PI3K/AKT activity. The molecular mechanism of reduced invasiveness was connected to the reduced expression of β-Catenin, an important marker of EMT (epithelial-mesenchymal transition). Ero1, a protein involved in clearing unfolded proteins and a member of the ER-Stress (endoplasmic reticulum-stress) pathway was also markedly reduced. Furthermore, Mesothelin silencing caused a significant increase in fraction of cancer cells in S-phase. In next step, treatment of ovarian cancer cells (OVca429) with a lentivirus expressing anti-mesothelin microRNA resulted in significant loss of viability, invasiveness, and morphological alterations. Therefore, we propose the inhibition of Mesothelin as a potential novel strategy for targeting human malignancies.
doi:10.1371/journal.pone.0033214
PMCID: PMC3317639
PMID: 22485139
The title compound, [Co(C7H5O2)2(C12H16N3O2)2(H2O)2], was obtained from a conventional solvent evaporation method. The complex molecule is centrosymmetric, so pairs of equivalent ligands lie trans to each other in a slightly distorted octahedral CoN2O4 geometry. The CoII ion is coordinated by the pyridine N atoms from NITpPy ligands [NITpPy is 4,4,5,5-tetramethyl-2-(pyridin-4-yl)imidazoline-1-oxyl 3-oxide), water O atoms and two monodentate benzoate O atoms. The complex molecules are connected by O—H⋯O hydrogen bonds between water molecules and benzoate ligands, forming chains parallel to [100]. π–π stacking interactions between the benzoate ligands with centroid–centroid distances of 3.752 (2) Å connect the chains into layers parallel to (10-1).
doi:10.1107/S1600536812012251
PMCID: PMC3343890
PMID: 22589858
In the title complex, [Mn(N3)2(C8H8N6)2], the complete molecule is generated by the application of twofold symmetry, and is in a distorted octahedral environment, coordinated by four N atoms of two bidentate 6-(pyridin-2-yl)-1,3,5-triazine-2,4-diamine ligands and two N atoms from two azide anions. The two chelated 6-(pyridin-2-yl)-1,3,5-triazine-2,4-diamine ligands form a dihedral angle 74.75 (5)°. The mononuclear molecules are alternatively linked into layers parallel to the ac plane via N—H⋯N hydrogen bonds. Adjacent layers are connected into a three-dimensional supramolecular framework by futher N—H⋯N hydrogen-bonding interactions.
doi:10.1107/S160053681201046X
PMCID: PMC3343829
PMID: 22589803
In this paper, a sensitive chronocoulometric deoxyribonucleic acid (DNA) biosensor based on a nanostructure gold electrode was fabricated for detection of the femtomolar level survivin gene which was correlated with osteosarcoma by using hexaamine-ruthenium III complexes, [Ru(NH3)6]3+, as the electrochemical indicator. The effect of different frequencies on the real surface area of the nanostructure gold electrode obtained by repetitive square-wave oxidation reduction cycle was investigated. At the optimal frequency of 8000 Hz, the real surface of the developed nanostructure gold electrode was about 42.5 times compared with that of the bare planar gold electrode. The capture probe DNA was immobilized on the nanostructure gold electrode and hybridized with target DNA. Electrochemical signals of hexaamine-ruthenium III bound to the anionic phosphate of DNA strands via electrostatic interactions were measured by chronocoulometry before and after hybridization. The increase of the charges of hexaamine-ruthenium III was observed upon hybridization of the probe with target DNA. Results indicate that this DNA biosensor could detect the femtomole (fM) concentration of the DNA target quantitatively in the range of 50 fM to 250 fM; the detection limit of this DNA biosensor was 5.6 fM (signal to noise = 3). This new biosensor exhibits excellent sensitivity and selectivity and has been used for an assay of polymerase chain reaction (PCR) with a satisfactory result.
doi:10.2147/IJN.S27794
PMCID: PMC3273984
PMID: 22334782
chronocoulometric DNA biosensor; survivin gene; hexaamine-ruthenium III complexes; nanostructure gold electrode; femtomolar level
Silicalite-poly(furfuryl alcohol) [PFA] composite membranes were prepared by solution casting of silicalite-furfuryl alcohol [FA] suspension on a porous polysulfone substrate and subsequent in situ polymerization of FA. X-ray diffraction, nitrogen sorption, thermogravimetric analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy were used to characterize silicalite nanocrystals and silicalite-PFA composite membranes. The silicalite-PFA composite membrane with 20 wt.% silicalite loading exhibits good oxygen/nitrogen selectivity (4.15) and high oxygen permeability (1,132.6 Barrers) at 50°C. Silicalite-PFA composite membranes are promising for the production of oxygen-enriched air for various applications.
doi:10.1186/1556-276X-6-637
PMCID: PMC3261223
PMID: 22209012
poly(furfuryl alcohol); silicalite; composite membrane; air separation
As functional magnetic resonance imaging (fMRI) studies have yielded increasing amounts of information about the brain’s spontaneous activity, they have revealed fMRI’s potential to locate changes in brain hemodynamics that are associated with neuropsychiatric disorders. In this paper, we review studies that support the notion that changes in brain spontaneous activity observed by fMRI can be used as potential biomarkers for diagnosis and treatment evaluation in neuropsychiatric disorders. We first review the methods used to study spontaneous activity from the perspectives of (1) the properties of local spontaneous activity, (2) the spatial pattern of spontaneous activity, and (3) the topological properties of brain networks. We also summarize the major findings associated with major neuropsychiatric disorders obtained using these methods. Then we review the pilot studies that have used spontaneous activity to discriminate patients from normal controls. Finally, we discuss current challenges and potential research directions to further elucidate the clinical use of spontaneous brain activity in neuropsychiatric disorders.
doi:10.1007/s11571-010-9126-9
PMCID: PMC2974101
PMID: 22132039
Resting-state fMRI; Low frequency fluctuation; Functional connectivity; Alzheimer’s disease; Schizophrenia
Ma, Ning | Huang, Zhibin | Chen, Xiaohui | He, Fei | Wang, Kun | Liu, Wei | Zhao, Linfeng | Xu, Xiangmin | Liao, Wangjun | Ruan, Hua | Luo, Shenqiu | Zhang, Wenqing | Wen, Zilong
Hematopoiesis is a complicated and dynamic process about which the molecular mechanisms remain poorly understood. Danio rerio (zebrafish) is an excellent vertebrate system for studying hematopoiesis and developmental mechanisms. In the previous study, we isolated and identified a cloche172 (clo172) mutant, a novel allele compared to the original cloche (clo) mutant, through using complementation test and initial mapping. Here, according to whole mount in-situ hybridization, we report that the endothelial cells in clo172 mutant embryos, although initially developed, failed to form the functional vascular system eventually. In addition, further characterization indicates that the clo172 mutant exhibited weaker defects instead of completely lost in primitive erythroid cells and definitive hematopoietic cells compared with the clos5 mutant. In contrast, primitive myeloid cells were totally lost in clo172 mutant. Furthermore, these reappeared definitive myeloid cells were demonstrated to initiate from the remaining hematopoietic stem cells (HSCs) in clo172 mutant, confirmed by the dramatic decrease of lyc in clo172runx1w84x double mutant. Collectively, the clo172 mutant is a weak allele compared to the clos5 mutant, therefore providing a model for studying the early development of hematopoietic and vascular system, as well as an opportunity to further understand the function of the cloche gene.
doi:10.1371/journal.pone.0027540
PMCID: PMC3223178
PMID: 22132109
Introduction
Contractures, ectropion and scarring, the most common sequelae of skin grafts after eyelid burn injuries, can result in corneal exposure, corneal ulceration and even blindness. Split-thickness or full-thickness skin grafts are commonly used for the treatment of acute eyelid burns. Plasma exudation and infection are common early complications of eyelid burns, which decrease the success rate of grafts.
Case presentation
We present the cases of eight patients, two Chinese women and six Chinese men. The first Chinese woman was 36 years old, with 70% body surface area second or third degree flame burn injuries involving her eyelids on both sides. The other Chinese woman was 28 years old, with sulfuric acid burns on her face and third degree burn on her eyelids. The six Chinese men were aged 21, 31, 38, 42, 44, and 55 years, respectively. The 38-year-old patient was transferred from the ER with 80% body surface area second or third degree flame burn injuries and third degree burn injuries to his eyelids. The other five men were all patients with flame burn injuries, with 7% to 10% body surface area third degree burns and eyelids involved. All patients were treated with a modified surgical procedure consisting of separation and loosening of the musculus orbicularis oculi between tarsal plate and septum orbital, followed by grafting a large full-thickness skin graft in three days after burn injury. The use of our modified surgical procedure resulted in 100% successful eyelid grafting on first attempt, and all our patients were in good condition at six-month follow-up.
Conclusions
This new surgical technique is highly successful in treating eyelid burn injuries, especially flame burn injuries of the eyelid.
doi:10.1186/1752-1947-5-373
PMCID: PMC3212825
PMID: 21843322
The rhizome of Atractylodes ovata De Candolle is rich in essential oils, which are usually removed by processing. In this study, anti-oxidative abilities of essential oils and aqueous extracts of A. ovata rhizome were explored, and the influence of processing on the anti-oxidative abilities was examined. Essential oils and aqueous extracts of A. ovata were extracted by boiling water and steam distillation, respectively. Quality of these two A. ovata samples was controlled by HPLC and GC-MS system, and anti-oxidative abilities were then evaluated. Results showed that surface color of A. ovata turned to brown and chemical components were changed by processing. Contents of both atractylon and atractylenolide II decreased in the essential oils, but only the contents of atractylon decreased by processing. Atractylenolide III increased in both A. ovata samples. However, A. ovata essential oils displayed stronger anti-oxidative abilities than aqueous extracts in DPPH-scavenging, TBH-induced lipid peroxidation and catalase activity assays. Moreover, the bioactivity of essential oils from raw A. ovata was stronger than oils from processed A. ovata. On the other hand, cytotoxicity of A. ovata essential oils was stronger than that of aqueous extracts, and was more sensitive on H9C2 cell than NIH-3T3 and WI-38 cells. In contrast, stir-frying processing method increased cytotoxicity of essential oils, but the cytotoxicity was ameliorated when processed with assistant substances. The results suggested that phytochemical components and bioactivity of A. ovata were changed after processing and the essential oils from raw A. ovata showed better anti-oxidative and fewer cytotoxicity effects.
doi:10.1093/ecam/neq006
PMCID: PMC3135905
PMID: 21799672
Background
To evaluate whether there are differences in the cerebral response to intraesophageal acid and psychological anticipation stimuli among subtypes of gastroesophageal reflux disease (GERD).
Methods
Thirty nine patients with GERD and 11 healthy controls were enrolled in this study after gastroscopy and 24 hr pH monitoring. GERD subjects were divided into four subgroups: RE (reflux esophagitis), NERD+ (non-erosive reflux disease with excessive acid reflux), NERD-SI+ (normal acid exposure and positive symptom index) and NERD-SI+ (normal acid exposure and negative symptom index, but responded to proton pump inhibitor trial). Cerebral responses to intraesophageal acid and psychological anticipation were evaluated with fMRI.
Results
During intraesophageal acid stimulation, the prefrontal cortex (PFC) region was significantly activated in all subgroups of GERD; the insular cortex (IC) region was also activated in RE, NERD+ and NERD-SI- groups; the anterior cingulated cortex (ACC) region was activated only in RE and NERD-SI- groups. The RE subgroup had the shortest peak time in the PFC region after acid was infused, and presented the greatest change in fMRI signals in the PFC and ACC region (P = 0.008 and P = 0.001, respectively). During psychological anticipation, the PFC was significantly activated in both the control and GERD groups. Activation of the IC region was found in the RE, NERD-SI+ and NERD-SI- subgroups. The ACC was activated only in the NERD-SI+ and NERD-SI- subgroups. In the PFC region, the NERD-SI- subgroup had the shortest onset time (P = 0.008) and peak time (P < 0.001). Compared with actual acid infusion, ACC in RE and IC in NERD+ were deactivated while additional areas including the IC and ACC were activated in the NERD-SI+ group; and in NERD-SI- group, onset-time and peak time in the PFC and IC areas were obviously shorter in induced anticipation than in actual acid infusion.
Conclusions
The four subgroups of GERD patients and controls showed distinctly different activation patterns and we therefore conclude GERD patients have different patterns of visceral perception and psychological anticipation. Psychological factors play a more important role in NERD-SI+ and NERD-SI- groups than in RE and NERD+ groups.
doi:10.1186/1471-230X-11-28
PMCID: PMC3073936
PMID: 21439078
The asymmetric unit of the title compound, C34H28S8, contains two crystallographically independent half-molecules. The molecules lie on centers of inversion. The four benzene rings of each molecule are substantially twisted from the planes of the 1,3-dithiole rings, forming dihedral angles of 43.6 (2) and 61.4 (1)° in one molecule and 54.2 (1) and 65.2 (1)° in the other.
doi:10.1107/S1600536811007823
PMCID: PMC3099894
PMID: 21754105
Optoacoustic Tomography (OAT) is a hybrid imaging modality that combines the advantages of optical and ultrasound imaging. Most existing reconstruction algorithms for OAT assume that the ultrasound transducers employed to record the measurement data are point-like. When transducers with large detecting areas and/or compact measurement geometries are utilized, this assumption can result in conspicuous image blurring and distortions in the reconstructed images. In this work, a new OAT imaging model that incorporates the spatial and temporal responses of an ultrasound transducer is introduced. A discrete form of the imaging model is implemented and its numerical properties are investigated. We demonstrate that use of the imaging model in an iterative reconstruction method can improve the spatial resolution of the optoacoustic images as compared to those reconstructed assuming point-like ultrasound transducers.
doi:10.1109/TMI.2010.2072514
PMCID: PMC3033994
PMID: 20813634
Optoacoustic tomography; photoacoustic tomography; thermoacoustic tomography
Retinoids and carotenoids are frequently used as antioxidants to prevent cancer. In this study, a panel of retinoids and carotenoids was examined to determine their effects on activation of RXR/CAR-mediated pathway and regulation of CYP3A gene expression. Transient transfection assays of HepG2 cells revealed that five out of thirteen studied retinoids significantly induced RXRα/CAR-mediated activation of luciferase activity that is driven by the thymidine kinase promoter-linked with a PXR binding site in the CYP3A4 gene [tk-(3A4)3-Luc reporter]. All-trans retinoic acid (RA) and 9-cis RA were more effective than CAR agonist TCBOPOP in induction of the tk-(3A4)3-Luc reporter. Addition of retinoid and TCBOPOP further enhanced the inducibility and the induction was preferentially mediated by RXRα/CAR and RXRγ/CAR heterodimer. Chromatin immunoprecipitation assay showed that retinoids recruit RXRα and CAR to the proximal ER6 and distal XREM nuclear receptor response elements of the CYP3A4 gene promoter. The experimental data demonstrates that retinoids can effectively regulate CYP3A gene expression through the RXR/CAR-mediated pathway.
doi:10.1016/j.bcp.2009.08.012
PMCID: PMC2784018
PMID: 19686701
RXR; CAR; Retinoid; CYP3A; Nuclear receptor
The pregnane x receptor (PXR) is a nuclear receptor transcription factor regulating drug-metabolizing enzymes and transporters that facilitate xenobiotic and endobiotic detoxification. Recent studies demonstrate that PXR is important in abrogating intestinal tissue damage. This study examines the role of PXR in lipopolysaccharide (LPS)/D-galactosamine (GalN)-induced acute liver injury using wild type and PXR-null mice. LPS/GalN-treated PXR-null mice had greater increases of alanine aminotransferase (ALT), hepatocyte apoptosis, necrosis, and hemorrhagic liver injury than wild type mice. LPS/GalN-mediated phosphorylation of JNK1/2 and ERK1/2 was differentially regulated in wild type and PXR-null mice. Importantly, LPS/GalN-induced hepatic Stat3 survival signaling was impaired and early activation of Jak2 was delayed in PXR-null mice. Expression levels of pro-survival proteins Bcl-xL and heme oxygenase-1 (HO-1), which are downstream of Stat3, were substantially lower in PXR-null than wild type mouse livers after LPS/GalN treatment. Autophagy is also involved in LPS/GalN-induced liver injury. Lack of PXR resulted in a significant reduction of LC3B-I, -II as well as Beclin-1 protein levels after LPS/GalN treatment. Taken together, PXR is a critical hepatoprotective factor. Increases of LPS/GalN-induced hepatocyte apoptosis and liver injury in PXR-null mice are due to deregulated MAP kinase activation as well as delayed Jak2/Stat3 activation, which lead to a compromise in defense mechanisms that involve Bcl-xL-, HO-1, and autophagy-mediated pathways.
doi:10.1038/labinvest.2009.129
PMCID: PMC2814901
PMID: 19997066
Apoptosis; Jak2/Stat3; Liver Injury; MAP kinases; PXR; nuclear receptor