Graft-versus-host disease (GVHD) is a common complication of allogeneic bone marrow transplantation (BMT). Upregulation of inflammatory cytokines precedes the clinical presentation of GVHD and predicts its severity. In this report, thiol/redox metabolomics was used to identify metabolic perturbations associated with early preclinical (Day+4) and clinical (Day+10) stages of GVHD by comparing effects in Syngeneic (Syn; major histocompatibility complex- identical) and allogeneic transplant recipients (Allo BMT) in experimental models. While most metabolic changes were similar in both groups, plasma glutathione (GSH) was significantly decreased, and GSH disulfide (GSSG) was increased after allogeneic compared to syngeneic recipient and non-transplant controls. The early oxidation of the plasma GSH/GSSG redox couple was also observed irrespective of radiation conditioning treatment and was accompanied by significant rise in hepatic protein oxidative damage and ROS generation. Despite a significant rise in oxidative stress, compensatory increase in hepatic GSH synthesis was absent following Allo BMT. Early shifts in hepatic oxidative stress and plasma GSH loss preceded a statistically significant rise in TNF-α. To identify metabolomic biomarkers of hepatic GVHD injury, plasma metabolite concentrations analyzed at Day+10 were correlated with hepatic organ injury. GSSG (oxidized GSH) and β-alanine, were positively correlated, and plasma GSH cysteinylglycine, and branched chain amino acids were inversely correlated with hepatic injury. Although changes in plasma concentrations of cysteine, cystathionine (GSH precursors) and cysteinylglycine (a GSH catabolite) were not significant by univariate analysis, principal component analysis (PCA) indicated that accumulation of these metabolites after Allo BMT contributed significantly to early GVHD in contrast to Syn BMT. In conclusion, thiol/redox metabolomic profiling implicates that early dysregulation of host hepatic GSH metabolism and oxidative stress in sub-clinical GVHD before elevated TNF-α levels is associated with GVHD pathogenesis. Future studies will probe the mechanisms for these changes and examine the potential of antioxidant intervention strategies to modulate GVHD.
Here we investigate the role of hypoxia inducible factor (HIF)-2α in coordinating the development of retinal astrocytic and vascular networks. Three Cre mouse lines were used to disrupt floxed Hif-2α, including Rosa26CreERT2, Tie2Cre, and GFAPCre. Global Hif-2α disruption by Rosa26CreERT2 led to reduced astrocytic and vascular development in neonatal retinas, whereas endothelial disruption by Tie2Cre had no apparent effects. Hif-2α deletion in astrocyte progenitors by GFAPCre significantly interfered with the development of astrocytic networks, which failed to reach the retinal periphery and were incapable of supporting vascular development. Perplexingly, the abundance of strongly GFAP+ mature astrocytes transiently increased at P0 before they began to lag behind the normal controls by P3. Pax2+ and PDGFRα+ astrocytic progenitors and immature astrocytes were dramatically diminished at all stages examined. Despite decreased number of astrocyte progenitors, their proliferation index or apoptosis was not altered. The above data can be reconciled by proposing that HIF-2α is required for maintaining the supply of astrocyte progenitors by slowing down their differentiation into non-proliferative mature astrocytes. HIF-2α deficiency in astrocyte progenitors may accelerate their differentiation into astrocytes, a change which greatly interferes with the replenishment of astrocyte progenitors due to insufficient time for proliferation. Rapidly declining progenitor supply may lead to premature cessation of astrocyte development. Given that HIF-2α protein undergoes oxygen dependent degradation, an interesting possibility is that retinal blood vessels may regulate astrocyte differentiation through their oxygen delivery function. While our findings support the consensus that retinal astrocytic template guides vascular development, they also raise the possibility that astrocytic and vascular networks may mutually regulate each other's development, mediated at least in part by HIF-2α.
Myeloid-derived suppressor cells (MDSCs) play an important role in impairing the function of T cells. We characterized MDSCs in two chronic hepatitis C (CHC) cohorts: a cross-sectional group that included 61 treatment-naive patients with CHC, 14 rapid virologic response (RVR) cases and 22 early virologic response (EVR) cases; and a longitudinal group of 13 cases of RVR and 10 cases of EVR after pegylated-interferon-α/ribavirin treatment for genotype 1b HCV infection. Liver samples from 32 CHC patients and six healthy controls were subjected to immunohistochemical analysis. MDSCs frequency in treatment-naive CHC was significantly higher than in RVR, EVR, or healthy subjects and was positively correlated with HCV RNA. Patients infected with HCV genotype 2a had a significantly higher frequency of MDSCs than those infected with genotype 1b. Decreased T cell receptor (TCR) ζ expression on CD8+ T cells was significantly associated with an increased frequency of MDSCs in treatment-naive CHC patients and was restored by L-arginine treatment in vitro. Increased numbers of liver arginase-1+ cells were closely associated with the histological activity index in CHC. The TCR ζ chain was significantly downregulated on hepatic CD8+ T cells in CHC. During antiviral follow up, MDSCs frequency in peripheral blood mononuclear cells was directly correlated with the HCV RNA load in the plasma and inversely correlated with TCR ζ chain expression in CD8+ T cells in both RVR and EVR cases. Notably, the RVR group had a higher frequency of MDSCs at baseline than the EVR group. Collectively, this study provides evidence that MDSCs might be associated with HCV persistence and downregulation of CD8 ζ chain expression.
arginase-1; hepatitis C virus; L-arginine; myeloid-derived suppressor cell; TCR ζ chain
Aptamers are oligonucleic acid or peptide molecules that bind to specific target molecules. As a novel and powerful class of ligands, aptamers are thought to have excellent potential for applications in the fields of biosensing, diagnostics and therapeutics. In this study, a new method for predicting aptamer-target interacting pairs was proposed by integrating features derived from both aptamers and their targets. Features of nucleotide composition and traditional amino acid composition as well as pseudo amino acid were utilized to represent aptamers and targets, respectively. The predictor was constructed based on Random Forest and the optimal features were selected by using the maximum relevance minimum redundancy (mRMR) method and the incremental feature selection (IFS) method. As a result, 81.34% accuracy and 0.4612 MCC were obtained for the training dataset, and 77.41% accuracy and 0.3717 MCC were achieved for the testing dataset. An optimal feature set of 220 features were selected, which were considered as the ones that contributed significantly to the interacting aptamer-target pair predictions. Analysis of the optimal feature set indicated several important factors in determining aptamer-target interactions. It is anticipated that our prediction method may become a useful tool for identifying aptamer-target pairs and the features selected and analyzed in this study may provide useful insights into the mechanism of interactions between aptamers and targets.
Mesenchymal stem cells (MSCs) are multipotent, tissue-resident cells that can facilitate tissue regeneration and thus, show great promise as potential therapeutic agents. Functional MSCs have been isolated and characterized from a wide array of adult tissues and are universally identified by the shared expression of a core panel of MSCs markers. One of these markers is the multifunctional cell surface peptidase CD13 that has been shown to be expressed on human and murine MSCs from many tissues. To investigate whether this universal expression indicates a functional role for CD13 in MSC biology we isolated, expanded and characterized MSCs from bone marrow of wild type (WT) and CD13KO mice. Characterization of these cells demonstrated that both WT and CD13KO MSCs expressed the full complement of MSC markers (CD29, CD44, CD49e, CD105, Sca1), showed comparable proliferation rates and were capable of differentiating toward the adipogenic and osteogenic lineages. However, MSCs lacking CD13 were unable to differentiate into vascular cells, consistent with our previous characterization of CD13 as an angiogenic regulator. Compared to WT MSCs, adhesion and migration on various extracellular matrices of CD13KO MSCs were significantly impaired, which correlated with decreased phospho-FAK levels and cytoskeletal alterations. Crosslinking human MSCs with activating CD13 antibodies increased cell adhesion to endothelial monolayers and induced FAK activation in a time dependent manner. In agreement with these in vitro data, intramuscular injection of CD13KO MSCs in a model of severe ischemic limb injury resulted in significantly poorer perfusion, decreased ambulation, increased necrosis and impaired vascularization compared to those receiving WT MSCs. This study suggests that CD13 regulates FAK activation to promote MSC adhesion and migration, thus, contributing to MSC-mediated tissue repair. CD13 may present a viable target to enhance the efficacy of mesenchymal stem cell therapies.
CD13; mesenchymal stem cells; adhesion; cell transplantation; hindlimb ischemia
Trastuzumab is a successful rationally designed ERBB2-targeted therapy. However, about half of individuals with ERBB2-overexpressing breast cancer do not respond to trastuzumab-based therapies, owing to various resistance mechanisms. Clinically applicable regimens for overcoming trastuzumab resistance of different mechanisms are not yet available. We show that the nonreceptor tyrosine kinase c-SRC (SRC) is a key modulator of trastuzumab response and a common node downstream of multiple trastuzumab resistance pathways. We find that SRC is activated in both acquired and de novo trastuzumab-resistant cells and uncover a novel mechanism of SRC regulation involving dephosphorylation by PTEN. Increased SRC activation conferred considerable trastuzumab resistance in breast cancer cells and correlated with trastuzumab resistance in patients. Targeting SRC in combination with trastuzumab sensitized multiple lines of trastuzumab-resistant cells to trastuzumab and eliminated trastuzumab-resistant tumors in vivo, suggesting the potential clinical application of this strategy to overcome trastuzumab resistance.
Ascoviruses are double-stranded DNA viruses that are pathogenic to lepidopteran hosts, particularly noctuid larvae. Infection of a larva is characterized by retarded growth, reduced feeding and yellowish body color. In this paper, we reported the growth and development of three major agricultural noctuid insect pests, Helicoverpa armigera (Hübner), Spodoptera exigua (Hübner) and Spodoptera litura (Fabricius), infected with Heliothis virescens ascovirus 3h (HvAV-3h). Using 10-fold serial dilutions (0 to 7) of HvAV-3h-containing hemolymph to infect S. litura larvae, we found no significant difference in larval mortalities from 0 to 103-fold dilutions; however, significant differences were observed at 104-fold dilution and above. Using a 10-fold dilution of HvAV-3h-containing hemolymph to infect H. armigera, S. exigua and S. litura larvae, we found that the growth and development were significantly affected. All infected larvae could not pupate; the survival times of treated H. armigera, S. litura and S. exigua larvae were significantly longer than untreated control larvae. Body weight showed significant difference between treated and untreated control group from day 1 after inoculation in H. armigera and S. exigua, but day 2 in S. litura. Additionally, food intake also showed significant difference between treated and untreated control group from day 2 after inoculation in H. armigera and S. litura, but day 3 in S. exigua.
A mathematical model for the relationship between the populations of giant pandas and two kinds of bamboo is established. We use the impulsive perturbations to take into account the effect of a sudden collapse of bamboo as a food source. We show that this system is uniformly bounded. Using the Floquet theory and comparison techniques of impulsive equations, we find conditions for the local and global stabilities of the giant panda-free periodic solution. Moreover, we obtain sufficient conditions for the system to be permanent. The results provide a theoretical basis for giant panda habitat protection.
Most drugs have beneficial as well as adverse effects and exert their biological functions by adjusting and altering the functions of their target proteins. Thus, knowledge of drugs target proteins is essential for the improvement of therapeutic effects and mitigation of undesirable side effects. In the study, we proposed a novel prediction method based on drug/compound ontology information extracted from ChEBI to identify drugs target groups from which the kind of functions of a drug may be deduced. By collecting data in KEGG, a benchmark dataset consisting of 876 drugs, categorized into four target groups, was constructed. To evaluate the method more thoroughly, the benchmark dataset was divided into a training dataset and an independent test dataset. It is observed by jackknife test that the overall prediction accuracy on the training dataset was 83.12%, while it was 87.50% on the test dataset—the predictor exhibited an excellent generalization. The good performance of the method indicates that the ontology information of the drugs contains rich information about their target groups, and the study may become an inspiration to solve the problems of this sort and bridge the gap between ChEBI ontology and drugs target groups.
Icariin has been mostly reported to enhance bone fracture healing and treat postmenopausal osteoporosis in ovariectomized animal model. As another novel animal model of osteoporosis, there is few publication about the effect of Icariin on osteoprotegerin-deficient mice. Therefore, the goal of this study is to find the effect on bone formation and underlying mechanisms of Icariin in osteoprotegerin (OPG) knockout (KO) mice. We found that Icariin significantly stimulated new bone formation after local injection over the surface of calvaria at the dose of 5 mg/kg per day. With this dose, Icariin was also capable of significantly reversing OPG-deficient-induced bone loss and bone strength reduction. Real-time PCR analysis showed that Icariin significantly upregulated the expression of BMP2, BMP4, RUNX2, OC, Wnt1, and Wnt3a in OPG KO mice. Icariin also significantly increased the expression of AXIN2, DKK1, TCF1, and LEF1, which are the direct target genes of β-catenin signaling. The in vitro studies showed that Icariin induced osteoblast differentiation through the activation of Wnt/β-catenin-BMP signaling by in vitro deletion of the β-catenin gene using β-cateninfx/fx mice. Together, our findings demonstrate that Icariin significantly reverses the phenotypes of OPG-deficient mice through the activation of Wnt/β-catenin-BMP signaling.
Objective. To investigate VIP effect on the cytotoxicity of NK cell to gastric cancer cells in vitro and the relation between the effect with the NKG2D signal molecules in NK cells. Material and Methods. NK cells were purified from peripheral blood mononuclear cells (PBMC). Before and after NK cells were incubated with VIP or its antagonist (D-p-Cl-Phe6,Leu17)-VIP, we detected the cytotoxicity of NK cells to MKN45 gastric cancer cells by MTT and detected the expressions of NKG2D, DAP10, and NF-κB proteins and mRNAs in NK cells by immunocytochemistry and RT-PCR in those conditions. Then we analyzed the effect of VIP and its antagonist on the cytotocicity of NK cell to gastric cancer cells and on expressions of NKG2D, DAP10, and NF-κB signal molecules in NK cells. Results. VIP could inhibit the cytotoxicity of NK cells to MKN45 cells and could inhibit the expressions of NKG2D, DAP10, and NF-κB in NK cells. However, (D-p-Cl-Phe6, Leu17)-VIP could reverse those effects. Conclusions. The VIP inhibited the cytotoxicity of NK cell to MKN45 cells which might get through inhibiting the expressions of NKG2D signal molecules in NK cells. This may be one mechanism of gastric cancer cells escaping organism immune clearance.
Over the last few decades intensive studies have been carried out on the molecular targets mediating general anesthesia as well as the effects of general anesthetics. The γ-aminobutyric acid type A receptor (GABAAR) has been indicated as the primary target of general anaesthetics such as propofol, etomidate and isoflurane, and sedating drugs including benzodiazepines and barbiturates. The GABAAR is also involved in drug tolerance and dependence. However, the involvement of other ion channels is possible.
Using reverse transcription and quantitative PCR techniques, we systematically investigated changes in the mRNA levels of ion channel genes in response to exposure to midazolam, pentobarbital and ketamine in a freshwater model animal, Daphnia pulex. To retrieve the sequences of Daphnia ion channel genes, Blast searches were performed based on known human or Drosophila ion channel genes. Retrieved sequences were clustered with the maximum-likelihood method. To quantify changes in gene expression after the drug treatments for 4 hours, total RNA was extracted and reverse transcribed into cDNA and then amplified using quantitative PCR.
A total of 108 ion channel transcripts were examined, and 19, 11 and 11 of them are affected by midazolam (100 μM), pentobarbital (200 μM) and ketamine (100 μM), respectively, covering a wide variety of ion channel types. There is some degree of overlap with midazolam- and pentobarbital-induced changes in the mRNA expression profiles, but ketamine causes distinct changes in gene expression pattern.
In addition, flumazenil (10 μM) eliminates the effect of midazolam on the mRNA expression of the GABAA receptor subunit Rdl, suggesting a direct interaction between midazolam and GABAA receptors.
Recent research using high throughput technology suggests that changes in mRNA expression correlate with delayed protein expression. Therefore, the mRNA profile changes in our study may reflect the molecular targets not only in drug actions, but also in chronic drug addiction. Our data also suggest the possibility that hypnotic/anesthetic drugs are capable of altering the functions of the nervous system, as well as those non-nerve tissues with abundant ion channel expressions.
Midazolam; Pentobarbital; Ketamine; mRNA; Ion channel; Daphnia pulex
Objective. In our previous study, we found that some miRNAs were deregulated in hepatocellular carcinoma (HCC), including miR-183. However, the expression of miR-183 in the progression of benign liver diseases to HCC and its correlation with clinicopathologic factors remain undefined. Methods. MiR-183 expression was measured in normal controls (NC) (n = 21), chronic viral hepatitis B or C (CH) tissues (n = 10), liver cirrhosis (LC) tissues (n = 18), HCC tissues (n = 92), and adjacent nontumor tissues (NT) (n = 92) by quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR). Results. The expression levels of miR-183 were significantly higher in HCC than in NT, LC, CH, and NL (P = 0.001, P < 0.001, P = 0.011, P < 0.001, resp.). The upregulated miR-183 in HCC was correlated with TNM stage (P = 0.042) and cirrhosis (P = 0.025). The Kaplan-Meier survival analysis showed that miR-183 expression was not associated with the survival of HCC patients. However, miR-183 yielded an area under the curve (AUC) of 0.808 with 59.8% sensitivity and 91.8% specificity in discriminating HCC from benign liver diseases (CH and LC) or NC. Conclusions. The upregulated miR-183 may associate with onset and progression of HCC, but not with the patient survival. A further research is needed to determine the potential of miR-183 as biomarker for HCC.
In this study, the two-step PV method of immunohistochemistry was used to determine livin protein expression in HCC tissues, pericarcinoma tissues, hepatitis/hepatic cirrhosis tissues, and normal hepatic tissues, and livin protein expression was detected in the blood plasma of patients with HCC before and after surgery, subjects with hepatic cirrhosis and hepatitis, and healthy blood donors using ELISA. Livin protein expression was significantly higher in HCC tissues than that in normal hepatic tissues and hepatitis/hepatic cirrhosis tissues, with no significant difference between HCC tissues and pericarcinoma tissues. The HCC patients with positive livin protein expression had a significantly higher survival rate than those with negative livin protein expression. Livin protein expression was significantly higher in the blood plasma of patients with HCC before and after surgery and in patients with hepatic cirrhosis and hepatitis than that in healthy blood donors, whereas livin protein expression in the blood plasma of patients with HCC was not significantly different from that of patients with hepatic cirrhosis and hepatitis. Livin protein expression in HCC tissues did not correlate with that in the blood plasma of the same HCC patients. Livin protein expression may be a potential, effective indicator for assessing prognosis in patients with HCC.
This paper presents the microfabrication of an acoustic impedance gradient matching layer on a spherically-shaped piezoelectric ultrasonic transducer. The acoustic matching layer can be designed to achieve higher acoustic energy transmission and operating bandwidth. Also included in this paper are a theoretical analysis of the device design and a micromachining technique to produce the novel transducer. Based on a design of a lead titanium zirconium (PZT) micropillar array, the constructed gradient acoustic matching layer has much better acoustic transmission efficiency within a 20–50 MHz operation range compared to a matching layer with a conventional quarter-wavelength thickness Parylene deposition. To construct the transducer, periodic microcavities are built on a flexible copper sheet, and then the sheet forms a designed curvature with a ball shaping. After PZT slurry deposition, the constructed PZT micropillar array is released onto a curved thin PZT layer. Following Parylene conformal coating on the processed PZT micropillars, the PZT micropillars and the surrounding Parylene comprise a matching layer with gradient acoustic impedance. By using the proposed technique, the fabricated transducer achieves a center frequency of 26 MHz and a −6 dB bandwidth of approximately 65%.
PZT film; ultrasonic transducer; micromachining; acoustic impedance
Understanding what governs community assembly and the maintenance of biodiversity is a central issue in ecology, but has been a continuing debate. A key question is the relative importance of habitat specialization (niche assembly) and dispersal limitation (dispersal assembly). In the middle of the Loess Plateau, northwestern China, we examined how species turnover in Liaodong oak (Quercus wutaishanica) forests differed between observed and randomized assemblies, and how this difference was affected by habitat specialization and dispersal limitation using variation partitioning. Results showed that expected species turnover based on individual randomization was significantly lower than the observed value (P < 0.01). The turnover deviation significantly depended on the environmental and geographical distances (P < 0.05). Environmental and spatial variables significantly explained approximately 40% of the species composition variation at all the three layers (P < 0.05). However, their contributions varied among forest layers; the herb and shrub layers were dominated by environmental factors, whereas the canopy layer was dominated by spatial factors. Our results underscore the importance of synthetic models that integrate effects of both dispersal and niche assembly for understanding the community assembly. However, habitat specialization (niche assembly) may not always be the dominant process in community assembly, even under harsh environments. Community assembly may be in a trait-dependent manner (e.g., forest layers in this study). Thus, taking more species traits into account would strengthen our confidence in the inferred assembly mechanisms.
Loess Plateau; neutral theory; niche assembly; randomization model; variation partitioning
Vascular endothelial growth factor receptor-1 (VEGFR-1/Flt-1) is a potential therapeutic target for cardiovascular diseases, but its role in angiogenesis remains controversial. While germline Vegfr-1−/− embryos die of abnormal vascular development in association with excessive endothelial differentiation, mice lacking only the kinase domain are apparently healthy.
Methods and Results
We carried out Cre-loxP mediated knockout to abrogate the expression of all known VEGFR-1 functional domains in neonatal and adult mice, and analyzed developmental, pathophysiological, and molecular consequences. VEGFR-1 deficiency promoted tip cell formation and endothelial cell (EC) proliferation, and facilitated angiogenesis of blood vessels which matured and perfused properly. Vascular permeability was normal at the basal level, but elevated in response to high doses of exogenous VEGF-A. In the post-infarct ischemic cardiomyopathy model, VEGFR-1 deficiency supported robust angiogenesis and protected against myocardial infarction. VEGFR-1 knockout led to abundant accumulation of VEGFR-2 at the protein level, increased VEGFR-2 tyrosine phosphorylation transiently, and enhanced serine phosphorylation of Akt and ERK. Interestingly, increased angiogenesis, tip cell formation, vascular permeability, VEGFR-2 accumulation, and Akt phosphorylation could be partially rescued or suppressed by one or more of the following manipulations, including injection of VEGFR-2 selective inhibitor SU1498, anti-VEGF-A, or introduction of Vegfr-2+/− heterozygosity into Vegfr-1 somatic knockout mice.
Upregulation of VEGFR-2 abundance at the protein level contributes in part to increased angiogenesis in VEGFR-1 deficient mice.
angiogenesis; vasculature; VEGFR-1; VEGFR-2; retina
Post-transplant malignancy is the major cause of later death of recipients after liver transplantation. Tumor recurrence after liver transplantation for patients with hepatocellular carcinoma in the end stage of cirrhosis has been frequently encountered. However, de novo hepatocellular carcinoma originating from the liver allograft has only rarely been reported. Here we reported a case of de novo hepatocellular carcinoma developed 2 years after living donor liver transplantation for hepatitis B-related liver cirrhosis with viral YMDD mutation. To the best of our knowledge, this is the first report of de novo hepatocellular carcinoma in a liver graft with recurrent hepatitis B virus infection after liver transplantation for hepatitis B-related liver cirrhosis with YMDD mutation. Moreover, the de novo cancer first presented as a lung mass with minimal liver involvement and was obscured by a pulmonary fungal infection.
De novo hepatocellular carcinoma; Liver transplantation; Living donor liver transplantation; Hepatitis B recurrence; YMDD mutation
To investigate the mechanisms underlying the neuroprotective effect of L-serine, permanent focal cerebral ischemia was induced by occlusion of the middle cerebral artery while monitoring cerebral blood flow (CBF). Rats were divided into control and L-serine-treated groups after middle cerebral artery occlusion. The neurological deficit score and brain infarct volume were assessed. Nissl staining was used to quantify the cortical injury. L-serine and D-serine levels in the ischemic cortex were analyzed with high performance liquid chromatography. We found that L-serine treatment: 1) reduced the neurological deficit score, infarct volume and cortical neuron loss in a dose-dependent manner; 2) improved CBF in the cortex, and this effect was inhibited in the presence of apamin plus charybdotoxin while the alleviation of both neurological deficit score and infarct volume was blocked; and 3) increased the amount of L-serine and D-serine in the cortex, and inhibition of the conversion of L-serine into D-serine by aminooxyacetic acid did not affect the reduction of neurological deficit score and infarct volume by L-serine. In conclusion, improvement in regional CBF by L-serine may contribute to its neuroprotective effect on the ischemic brain, potentially through vasodilation which is mediated by the small- and intermediate-conductance Ca2+-activated K+ channels on the cerebral blood vessel endothelium.
Analyses of mitochondrial (mt) genome sequences in recent years challenge the current working hypothesis of Nematoda phylogeny proposed from morphology, ecology and nuclear small subunit rRNA gene sequences, and raise the need to sequence additional mt genomes for a broad range of nematode lineages.
We sequenced the complete mt genomes of three Ascaridia species (family Ascaridiidae) that infest chickens, pigeons and parrots, respectively. These three Ascaridia species have an identical arrangement of mt genes to each other but differ substantially from other nematodes. Phylogenetic analyses of the mt genome sequences of the Ascaridia species, together with 62 other nematode species, support the monophylies of seven high-level taxa of the phylum Nematoda: 1) the subclass Dorylaimia; 2) the orders Rhabditida, Trichinellida and Mermithida; 3) the suborder Rhabditina; and 4) the infraorders Spiruromorpha and Oxyuridomorpha. Analyses of mt genome sequences, however, reject the monophylies of the suborders Spirurina and Tylenchina, and the infraorders Rhabditomorpha, Panagrolaimomorpha and Tylenchomorpha. Monophyly of the infraorder Ascaridomorpha varies depending on the methods of phylogenetic analysis. The Ascaridomorpha was more closely related to the infraorders Rhabditomorpha and Diplogasteromorpha (suborder Rhabditina) than they were to the other two infraorders of the Spirurina: Oxyuridorpha and Spiruromorpha. The closer relationship among Ascaridomorpha, Rhabditomorpha and Diplogasteromorpha was also supported by a shared common pattern of mitochondrial gene arrangement.
Analyses of mitochondrial genome sequences and gene arrangement has provided novel insights into the phylogenetic relationships among several major lineages of nematodes. Many lineages of nematodes, however, are underrepresented or not represented in these analyses. Expanding taxon sampling is necessary for future phylogenetic studies of nematodes with mt genome sequences.
Mitochondrial genome; Ascaridia; Nematode; Gene arrangement; Phylogeny
The whipworm of humans, Trichuris trichiura, is responsible for a neglected tropical disease (NTD) of major importance in tropical and subtropical countries of the world. Whipworms also infect animal hosts, including pigs, dogs and non-human primates, cause clinical disease (trichuriasis) similar to that of humans. Although Trichuris species are usually considered to be host specific, it is not clear whether non-human primates are infected with T. trichiura or other species. In the present study, we sequenced the complete mitochondrial (mt) genome as well as the first and second internal transcribed spacers (ITS-1 and ITS-2) of Trichuris from the François’ leaf-monkey (langur), and compared them with homologous sequences from human- and pig-derived Trichuris. In addition, sequence comparison of a conserved mt ribosomal gene among multiple individual whipworms revealed substantial nucleotide differences among these three host species but limited sequence variation within each of them. The molecular data indicate that the monkey-derived whipworm is a separate species from that of humans. Future work should focus on detailed population genetic and morphological studies (by electron microscopy) of whipworms from various non-humans primates and humans.
Sini decoction is a well-known formula of traditional Chinese medicine, which has been used to treat cardiovascular disease for many years. Previously, we demonstrated that Sini decoction prevented doxorubicin-induced heart failure in vivo. However, its active components are still unclear. Thus, we investigated the active components of Sini decoction and their cardioprotective mechanisms in the in vitro neonatal rat cardiomyocytes and H9c2 cell line models of doxorubicin-induced cytotoxicity. Our results demonstrated that treatment with higenamine or -gingerol increased viability of doxorubicine-injured cardiomyocytes. Moreover, combined use of higenamine and -gingerol exerted more profound protective effects than either drug as a single agent, with effects similar to those of dexrazoxane, a clinically approved cardiac protective agent. In addition, we found that treatment with doxorubicin reduced SOD activity, increased ROS generation, enhanced MDA formation, induced release of LDH, and triggered the intrinsic mitochondria-dependent apoptotic pathway in cardiomyocytes, which was inhibited by cotreatment of higenamine and -gingerol. Most importantly, the cytoprotection of higenamine plus -gingerol could be abrogated by LY294002, a PI3K inhibitor. In conclusion, combination of higenamine and -gingerol exerts cardioprotective effect against doxorubicin-induced cardiotoxicity through activating the PI3K/Akt signaling pathway. Higenamine and -gingerol may be the active components of Sini decoction.
Hypertension induces cardiovascular hypertrophy and fibrosis. Infiltrated macrophages are critically involved in this process. We recently reported that inhibition of prolyl hydroxylase domain protein 2 (PHD2), which hydroxylates the proline residues of hypoxia‐inducible factor‐α (HIF‐α) and thereby induces HIF‐α degradation, suppressed inflammatory responses in macrophages. We examined whether myeloid‐specific Phd2 deletion affects hypertension‐induced cardiovascular remodeling.
Methods and Results
Myeloid‐specific PHD2‐deficient mice (MyPHD2KO) were generated by crossing Phd2‐floxed mice with LysM‐Cre transgenic mice, resulting in the accumulation of HIF‐1α and HIF‐2α in macrophage. Eight‐ to ten‐week‐old mice were given NG‐nitro‐L‐arginine methyl ester (L‐NAME), a nitric oxide synthase inhibitor, and Angiotensin II (Ang II) infusion. L‐NAME/Ang II comparably increased systolic blood pressure in control and MyPHD2KO mice. However, MyPHD2KO mice showed less aortic medial and adventitial thickening, and macrophage infiltration. Cardiac interstitial fibrosis and myocyte hypertrophy were also significantly ameliorated in MyPHD2KO mice. Transforming growth factor‐β and collagen expression were decreased in the aorta and heart from MyPHD2KO mice. Echocardiographic analysis showed that left ventricular hypertrophy and reduced ejection fraction induced by L‐NAME/Ang II treatment in control mice were not observed in MyPHD2KO mice. Administration of digoxin that inhibits HIF‐α synthesis to L‐NAME/Ang II‐treated MyPHD2KO mice reversed these beneficial features.
Phd2 deletion in myeloid lineage attenuates hypertensive cardiovascular hypertrophy and fibrosis, which may be mediated by decreased inflammation‐ and fibrosis‐associated gene expression in macrophages. PHD2 in myeloid lineage plays a critical role in hypertensive cardiovascular remodeling.
fibrosis; hypertrophy; hypoxia; macrophages; migration
The number of patients developing esophageal cancer after gastrectomy has increased. However, gastric remnant is very rarely used for reconstruction in esophageal cancer surgery because of the risk of anastomotic leakage resulting from insufficient blood flow. We present a case of esophageal cancer using gastric remnant for esophageal substitution after distal gastrectomy in a 57-year-old man who presented with a 1-month history of mild dysphagia and a background history of alcohol abuse. Gastroscopy showed a 1.2 cm × 1.0 cm bulge tumor of the lower third esophagus with the upper margin located 39 cm from the dental arcade. Computed tomography of the chest showed lower third esophageal wall thickening. The patient underwent en bloc radical esophagectomy with a two-field lymph node dissection of the upper abdomen and mediastinum via a left-sided posterolateral thoracotomy through the seventh intercostal space. The upper end of the esophagus was resected 5 cm above the tumor. The gastric remnant was used for reconstruction of the esophago-gastrostomy and placed in the left thoracic cavity. The patient started a liquid diet on postoperative day 8 and was discharged on the 10th postoperative day without complications. In this report, we demonstrate that the gastric remnant may be used for reconstruction in patients with esophageal cancer as a substitute organ after distal gastrectomy.
Gastric remnant; Distal; Gastrectomy; Esophageal cancer; Substitution