Disturbance of cellular functions results in the activation of stress-signaling pathways that aim at restoring homeostasis. We performed a genome-wide screen to identify components of the signal transduction of the mitochondrial unfolded protein response (UPRmt) to a nuclear chaperone promoter. We used the ROS generating complex I inhibitor paraquat to induce the UPRmt, and we employed RNAi exposure post-embryonically to allow testing genes whose knockdown results in embryonic lethality. We identified 54 novel regulators of the ROS–induced UPRmt. Activation of the UPRmt, but not of other stress-signaling pathways, failed when homeostasis of basic cellular mechanisms such as translation and protein transport were impaired. These mechanisms are monitored by a recently discovered surveillance system that interprets interruption of these processes as pathogen attack and depends on signaling through the JNK-like MAP-kinase KGB-1. Mutation of kgb-1 abrogated the inhibition of ROS–induced UPRmt, suggesting that surveillance-activated defenses specifically inhibit the UPRmt but do not compromise activation of the heat shock response, the UPR of the endoplasmic reticulum, or the SKN-1/Nrf2 mediated response to cytosolic stress. In addition, we identified PIFK-1, the orthologue of the Drosophila PI 4-kinase four wheel drive (FWD), and found that it is the only known factor so far that is essential for the unfolded protein responses of both mitochondria and endoplasmic reticulum. This suggests that both UPRs may share a common membrane associated mechanism.
Cellular respiration takes place in the mitochondria. Reactive oxygen species (ROS) are a damaging byproduct of cellular respiration. In adverse conditions, when the load of ROS becomes critical for mitochondrial function, a stress-response pathway, the unfolded protein response of the mitochondria (UPRmt), is triggered. This can be monitored by the activation of the hsp-6 gene. We used the model organism Caenorhabditis elegans to screen for genes required for the activation of hsp-6 and found 54 novel candidates. Surprisingly, most of the genes we identified serve basic cellular functions and are not plausible candidates for regulatory functions. However, this group of genes was recently shown to trigger a cellular surveillance–mediated stress response, sensing pathogen invasion and toxin attack, and forcing the animals to escape from environmental hazards. This mechanism partially requires signaling through the kinase KGB-1. In worms in which KGB-1 was inactivated, UPRmt was not longer interrupted by downregulation of the cellular surveillance activating genes. We suggest this surveillance system as a regulator of the UPRmt that prevents its activation when pathogen attack is sensed.
We report the draft genome sequence of the Rickettsia sp. strain MEAM1, which is a facultative symbiont from an invasive species of the whitefly Bemisia tabaci. The total length of the assembled genome is approximately 1.24 Mb, with 335 scaffolds and 1,247 coding sequences predicted within the genome.
Salmonella are important human and animal pathogens. Though highly related, the Salmonella lineages may be strictly adapted to different hosts or cause different diseases, from mild local illness like gastroenteritis to fatal systemic infections like typhoid. Therefore, rapid and accurate identification of Salmonella is essential for timely and correct diagnosis of Salmonella infections. The current identification methods such as 16S rRNA sequencing and multilocus sequence typing are expensive and time consuming. Additionally, these methods often do not have sufficient distinguishing resolution among the Salmonella lineages.
We compared 27 completely sequenced Salmonella genomes to identify possible genomic features that could be used for differentiation of individual lineages. We concatenated 2372 core genes in each of the 27 genomes and constructed a neighbor-joining tree. On the tree, strains of each serotype were clustered tightly together and different serotypes were unambiguously separated with clear genetic distances, demonstrating systematic genomic divergence among the Salmonella lineages. We made detailed comparisons among the 27 genomes and identified distinct sets of genomic differences, including nucleotide variations and genomic islands (GIs), among the Salmonella lineages. Two core genes STM4261 and entF together could unambiguously distinguish all Salmonella lineages compared in this study. Additionally, strains of a lineage have a common set of GIs and closely related lineages have similar sets of GIs.
Salmonella lineages have accumulated distinct sets of mutations and laterally acquired DNA (e.g., GIs) in evolution. Two genes entF and STM4261 have diverged sufficiently among the Salmonella lineages to be used for their differentiation. Further investigation of the distinct sets of mutations and GIs will lead to novel insights into genomic evolution of Salmonella and greatly facilitate the elucidation of pathogeneses of Salmonella infections.
p27kip1 (p27) is a cdk-inhibitory protein with an important role in the proliferation of many cell types. SCFSkp2 is the best studied regulator of p27 levels, but Skp2-mediated p27 degradation is not essential in vivo or in vitro. The molecular pathway that compensates for loss of Skp2-mediated p27 degradation has remained elusive. Here, we combine vascular injury in the mouse with genome-wide profiling to search for regulators of p27 during cell cycling in vivo. This approach, confirmed by RT-qPCR and mechanistic analysis in primary cells, identified miR-221/222 as a compensatory regulator of p27. The expression of miR221/222 is sensitive to proteasome inhibition with MG132 suggesting a link between p27 regulation by miRs and the proteasome. We then examined the roles of miR-221/222 and Skp2 in cell cycle inhibition by prostacyclin (PGI2), a potent cell cycle inhibitor acting through p27. PGI2 inhibited both Skp2 and miR221/222 expression, but epistasis, ectopic expression, and time course experiments showed that miR-221/222, rather than Skp2, was the primary target of PGI2. PGI2 activates Gs to increase cAMP, and increasing intracellular cAMP phenocopies the effect of PGI2 on p27, miR-221/222, and mitogenesis. We conclude that miR-221/222 compensates for loss of Skp2-mediated p27 degradation during cell cycling, contributes to proteasome-dependent G1 phase regulation of p27, and accounts for the anti-mitogenic effect of cAMP during growth inhibition.
Dengue virus (DV) infections cause mild dengue fever (DF) or severe life-threatening dengue hemorrhagic fever (DHF). The mechanisms that cause hemorrhage in DV infections remain poorly understood. Thrombomodulin (TM) is a glycoprotein expressed on the surface of vascular endothelial cells that plays an important role in the thrombin-mediated activation of protein C. Prior studies have shown that the serum levels of soluble TM (sTM) and macrophage migration inhibitory factor (MIF) are significantly increased in DHF patients compared to levels in DF patients or normal controls. In this study, we investigated how MIF and sTM concentrations are enhanced in the plasma of DHF patients and the potential effect of MIF on coagulation through its influence on two factors: thrombomodulin (TM) and intercellular adhesion molecule-1 (ICAM-1) in endothelial cells and monocytes. Recombinant human macrophage migration inhibitory factor (rMIF) was used to treat monocytic THP-1 cells and endothelial HMEC-1 cells or primary HUVEC cells. The subsequent expression of TM and ICAM-1 was assessed by immunofluorescent staining and flow cytometry analysis. Additionally, the co-incubation of THP-1 cells with various cell signaling pathway inhibitors was used to determine the pathways through which MIF mediated its effect. The data provided evidence that severe DV infections induce MIF expression, which in turn stimulates monocytes or endothelial cells to express TM and ICAM-1 via the Erk, JNK MAPK and the PI3K signaling pathways, supporting the idea that MIF may play an important role as a regulator of coagulation.
Arterial stiffening is a risk factor for cardiovascular disease, but how arteries stay supple is unknown. Here, we show that apolipoprotein E (apoE) and apoE-containing HDL maintain arterial elasticity by suppressing the expression of extracellular matrix genes. ApoE interrupts a mechanically driven feed-forward loop which increases the expression of collagen-I, fibronectin, and lysyl oxidase in response to substratum stiffening. These effects are independent of the apoE lipid-binding domain and transduced by Cox2 and miR-145. Arterial stiffness is increased in apoE-null mice, this stiffening can be reduced by administration of the lysyl oxidase inhibitor, BAPN, and BAPN treatment attenuates atherosclerosis despite highly elevated cholesterol. Macrophage abundance in lesions is reduced by BAPN in vivo, and monocyte/macrophage adhesion is reduced by substratum softening in vitro. We conclude that apoE and apoE-containing HDL promote healthy arterial biomechanics, and this confers protection from cardiovascular disease independent of the established apoE-HDL effect on cholesterol.
“Candidatus Hamiltonella defensa” is a facultative endosymbiont of the whitefly Bemisia tabaci. Herein, we report the first draft genome sequence of “Candidatus Hamiltonella defensa” from the invasive Mediterranean cryptic species of the B. tabaci complex. The 1.84-Mbp genome sequence comprises 404 contigs and contains 1,806 predicted protein-coding genes.
A mitochondrial manganese superoxide dismutase from an invasive species of the whitefly Bemisia tabaci complex (Bt-mMnSOD) was cloned and analyzed. The full length cDNA of Bt-mMnSOD is 1210 bp with a 675 bp open reading frame, corresponding to 224 amino acids, which include 25 residues of the mitochondrial targeting sequence. Compared with various vertebrate and invertebrate animals, the MnSOD signature (DVWEHAYY) and four conserved amino acids for manganese binding (H54, H102, D186 and H190) were observed in Bt-mMnSOD. Recombinant Bt-mMnSOD was overexpressed in Escherichia coli, and the enzymatic activity of purified mMnSOD was assayed under various temperatures. Quantitative real-time PCR analysis with whiteflies of different development stages showed that the mRNA levels of Bt-mMnSOD were significantly higher in the 4th instar than in other stages. In addition, the in vivo activities of MnSOD in the whitefly were measured under various conditions, including exposure to low (4 °C) and high (40 °C) temperatures, transfer from a favorable to an unfavorable host plant (from cotton to tobacco) and treatment with pesticides. Our results indicate that the whitefly MnSOD plays an important role in cellular stress responses and anti-oxidative processes and that it might contribute to the successful worldwide distribution of the invasive whitefly.
mitochondrial manganese superoxide dismutase; oxidative stress; whitefly; Bemisia tabaci
This study aimed to explore the mechanism of membranous ventricular septal defect complicated with tricuspid regurgitation and the significance of ventricular septal defect occlusion by echocardiography. A total of 43 patients with membranous ventricular septal defect complicated with tricuspid regurgitation were observed by echocardiography and the changes in length, area and volume of tricuspid regurgitation prior to and following ventricular septal defect occlusion were measured. There were four different mechanisms of membranous ventricular septal defect complicated with tricuspid regurgitation. The various indices of tricuspid regurgitation volume were significantly reduced following occlusion. Ventricular septal defect occlusion significantly reduces tricuspid regurgitation volume complicated with membranous ventricular septal defect and echocardiography is an ideal method to detect these changes.
tricuspid regurgitation; membranous ventricular septal defect; echocardiography; occlusion; interventional therapy
Gait deficits are important clinical symptoms of Parkinson’s disease (PD). However, existing behavioral tests for the detection of motor impairments in rodents with systemic dopamine depletion only measure akinesia and dyskinesia, and data focusing on gait are scarce. We evaluated gait changes in the methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced C57BL/6 murine model of PD by using a computer-assisted CatWalk system. Correlations of gait parameters with tyrosine hydroxylase (TH) protein levels in the substantia nigra (SN) were also investigated.
The gait readouts, including the walking duration, variation of walking speed, step cycle, duty cycle, stance, initial dual stance, terminal dual stance, three- and four-point supports, and the base of support between hind limbs was noted to increase significantly one week after MPTP injection. In contrast, values of the stride length, cadence, swing speed, and diagonal dual support decreased substantially following MPTP treatment (p < 0.05). All of these changes lasted for three weeks after the last MPTP administration. Except for the stance in the fore limbs and the swing speed in the hind limbs, the gait variability in the PD mice showed a closer correlation with the protein levels of TH in the SN than the walking distances in the conventional open field test. Coordination parameters of the regularity index and step pattern were not affected in mice treated with MPTP.
Data of the study suggest that the computer-assisted CatWalk system can provide reliable and objective criteria to stratify gait changes arising from MPTP-induced bilateral lesions in C57/BL6 mice. The extent of gait changes was noted to correlate with the expression of the biomarker for dopaminergic neurons. This novel analytical method may hold promise in the study of disease progression and new drug screening in a murine PD model.
Parkinson’s disease; Gait; MPTP; Tyrosine hydroxylase; Neurochemical correlation
Renal interstitial fibrosis is characterized by increased extracellular matrix (ECM) synthesis. Epithelial-mesenchymal transition (EMT) in kidneys is driven by regulated expression of fibrogenic cytokines such as transforming growth factor-beta (TGF-β). Yam, or Dioscorea alata (DA) is an important herb in Chinese medicine widely used for the treatment of clinical diabetes mellitus. However, the fibrosis regulatory effect of DA is unclear. Thus, we examined TGF-β signaling mechanisms against EMT in rat fibroblast cells (NRK-49F). The characterization of DA water-extracts used various methods; after inducing cellular fibrosis in NRK-49F cells by treatment with β-hydroxybutyrate (β-HB) (10 mM), we used Western blotting to examine the protein expression in the TGF-β-related signal protein type I and type II TGF-β receptors, Smads2 and Smad3 (Smad2/3), pSmad2 and Smad3 (pSmad2/3), Smads4, Smads7, and EMT markers. These markers included E-cadherin, alpha-smooth muscle actin (α-SMA), and matrix metalloproteinase-2 (MMP-2). Bioactive TGF-β and fibronectin levels in the culture media were determined using ELISA. Expressions of fibronectin and Snail transcription factor, an EMT-regulatory transcription factor, were assessed by immunofluorescence staining. DA extract dose-dependently (50–200 µg/mL) suppressed β-HB-induced expression of fibronectin in NRK-49F cells concomitantly with the inhibition of Smad2/3, pSmad2/3, and Smad4. By contrast, Smad7 expression was significantly increased. DA extract caused a decrease in α-SMA (α-smooth muscle actin) and MMP-2 levels, and an increase in E-cadherin expression. We propose that DA extract might act as a novel fibrosis antagonist, which acts partly by down regulating the TGF-β/smad signaling pathway and modulating EMT expression.
Internal medicine includes several subspecialties. This study aimed to describe change trend of impact factors in different subspecialties of internal medicine during the past 12 years, as well as the developmental differences among each subspecialty, and the possible influencing factors behind these changes and differences.
Nine subspecialties of internal medicine were chosen for comparison. All data were collected from the Science Citation Index Expanded and Journal Citation Reports database.
(1) Journal numbers in nine subspecialties increased significantly from 1998 to 2010, with an average increment of 80.23%, in which cardiac and cardiovascular system diseases increased 131.2% rank the first; hematology increased 45% rank the least. (2) Impact Factor in subspecialties of infectious disease, cardiac and cardiovascular system diseases, gastroenterology and hepatology, hematology, endocrinology and metabolism increased significantly (p<0.05), in which gastroenterology and hepatology had the largest increase of 65.4%. (3) Journal impact factor of 0–2 had the largest proportion in all subspecialties. Among the journals with high impact factor (IF>6), hematology had the maximum proportion of 10%, nephrology and respiratory system disease had the minimum of 4%. Among the journal with low impact factor (IF<2), journal in nephrology and allergy had the most (60%), while endocrinology and metabolism had the least (40%). There were differences in median number of IF among the different subspecialties (p<0.05), in which endocrinology and metabolism had the highest, nephrology had the lowest. (4) The highest IF had a correlation with journal numbers and total paper numbers in each field.
The IF of internal medicine journals showed an increasingly positive trend, in which gastroenterology and hepatology increase the most. Hematology had more high IF journals. Endocrinology and metabolism had higher average IF. Nephrology remained the lowest position. Numbers of journals and total papers were associated with the highest IF.
Genomic divergence between invasive and native species may provide insight into the molecular basis underlying specific characteristics that drive the invasion and displacement of closely related species. In this study, we sequenced the transcriptome of an indigenous species, Asia II 3, of the Bemisia tabaci complex and compared its genetic divergence with the transcriptomes of two invasive whiteflies species, Middle East Asia Minor 1 (MEAM1) and Mediterranean (MED), respectively.
More than 16 million reads of 74 base pairs in length were obtained for the Asia II 3 species using the Illumina sequencing platform. These reads were assembled into 52,535 distinct sequences (mean size: 466 bp) and 16,596 sequences were annotated with an E-value above 10-5. Protein family comparisons revealed obvious diversification among the transcriptomes of these species suggesting species-specific adaptations during whitefly evolution. On the contrary, substantial conservation of the whitefly transcriptomes was also evident, despite their differences. The overall divergence of coding sequences between the orthologous gene pairs of Asia II 3 and MEAM1 is 1.73%, which is comparable to the average divergence of Asia II 3 and MED transcriptomes (1.84%) and much higher than that of MEAM1 and MED (0.83%). This is consistent with the previous phylogenetic analyses and crossing experiments suggesting these are distinct species. We also identified hundreds of highly diverged genes and compiled sequence identify data into gene functional groups and found the most divergent gene classes are Cytochrome P450, Glutathione metabolism and Oxidative phosphorylation. These results strongly suggest that the divergence of genes related to metabolism might be the driving force of the MEAM1 and Asia II 3 differentiation. We also analyzed single nucleotide polymorphisms within the orthologous gene pairs of indigenous and invasive whiteflies which are helpful for the investigation of association between allelic and phenotypes.
Our data present the most comprehensive sequences for the indigenous whitefly species Asia II 3. The extensive comparisons of Asia II 3, MEAM1 and MED transcriptomes will serve as an invaluable resource for revealing the genetic basis of whitefly invasion and the molecular mechanisms underlying their biological differences.
Bemisia tabaci; Biological invasion; Genetic divergence; Indigenous species; Next generation sequencing; Transcriptome; Whitefly
Cardiac resynchronization therapy (CRT), in which both ventricles are paced to recoordinate contraction in hearts that are dyssynchronous from conduction delay, is the only heart failure (HF) therapy to date to clinically improve acute and chronic function while also lowering mortality. CRT acutely enhances chamber mechanical efficiency but chronically alters myocyte signaling, including improving β-adrenergic receptor reserve. We speculated that the latter would identify unique CRT effects that might themselves be effective for HF more generally. HF was induced in dogs by 6 weeks of atrial rapid pacing with (HFdys, left bundle ablated) or without (HFsyn) dyssynchrony. We used dyssynchronous followed by resynchronized tachypacing (each 3 weeks) for CRT. Both HFdys and HFsyn myocytes had similarly depressed rest and β-adrenergic receptor sarcomere and calcium responses, particularly the β2-adrenergic response, whereas cells subjected to CRT behaved similarly to those from healthy controls. CRT myocytes exhibited suppressed Gαi signaling linked to increased regulator of G protein (heterotrimeric guanine nucleotide–binding protein) signaling (RGS2, RGS3), yielding Gαs-biased β2-adrenergic responses. This included increased adenosine cyclic AMP responsiveness and activation of sarcoplasmic reticulum–localized protein kinase A. Human CRT responders also showed up-regulated myo-cardial RGS2 and RGS3. Inhibition of Gαi (with pertussis toxin, RGS3, or RGS2 transfection), stimulation with a Gαs-biased β2 agonist (fenoterol), or transient (2-week) exposure to dyssynchrony restored β-adrenergic receptor responses in HFsyn to the values obtained after CRT. These results identify a key pathway that is triggered by restoring contractile synchrony and that may represent a new therapeutic approach for a broad population of HF patients.
Bacterial pathogens display a variety of protection mechanisms against the inhibitory and lethal effects of host cationic antimicrobial peptides (CAMPs). To identify Yersinia pestis genes involved in CAMP-resistance, libraries of DSY101 (KIM6 caf1 pla psa) minitransposon Tn5AraOut mutants were selected at 37°C for resistance to the model CAMPs polymyxin B or protamine. This approach targeted genes that needed to be repressed (null mutations) or induced (upstream PBAD insertions) for the detection of CAMP resistance, and predictably for improved pathogen fitness in mammalian hosts. Ten mutants demonstrated increased resistance to polymyxin B or protamine, with the mapped mutations pointing towards genes suspected to participate in modifying membrane components, genes encoding transport proteins or enzymes, or the regulator of a ferrous iron uptake system (feoC). Not all the mutants were resistant to both CAMPs used for selection. None of the polymyxin B- and only some protamine-resistant mutants, including the feoC mutant, showed increased resistance to rat bonchoalveolar lavage fluid (rBALF) known to contain cathelicidin and β-defensin 1. Thus, findings on bacterial resistance to polymyxin B or protamine don’t always apply to CAMPs of the mammalian innate immune system, such as the ones in rBALF.
Yersinia pestis; minitransposon; polymyxin B; protamine; LL-37
The inhibition of the activity of β-secretase (BACE-1) is a potentially important approach for the treatment of Alzheimer disease. To explore the mechanism of inhibition, we describe the use of 46 X-ray crystallographic BACE-1/inhibitor complexes to derive quantitative structure-activity relationship (QSAR) models. The inhibitors were aligned by superimposing 46 X-ray crystallographic BACE-1/inhibitor complexes, and gCOMBINE software was used to perform COMparative BINding Energy (COMBINE) analysis on these 46 minimized BACE-1/inhibitor complexes. The major advantage of the COMBINE analysis is that it can quantitatively extract key residues involved in binding the ligand and identify the nature of the interactions between the ligand and receptor.
By considering the contributions of the protein residues to the electrostatic and van der Waals intermolecular interaction energies, two predictive and robust COMBINE models were developed: (i) the 3-PC distance-dependent dielectric constant model (built from a single X-ray crystal structure) with a q2 value of 0.74 and an SDEC value of 0.521; and (ii) the 5-PC sigmoidal electrostatic model (built from the actual complexes present in the Brookhaven Protein Data Bank) with a q2 value of 0.79 and an SDEC value of 0.41.
These QSAR models and the information describing the inhibition provide useful insights into the design of novel inhibitors via the optimization of the interactions between ligands and those key residues of BACE-1.
BACE-1 Inhibitors; Superimposition; 3D-QSAR; COMBINE
The MEAM1 (B biotype) Bemisia tabaci (Gennadius) is one of the most widespread and damaging whitefly cryptic species. Our previous studies discovered that the MEAM1 whitefly indirectly benefits from interactions with the tomato yellow leaf curl China virus (TYLCCNV) via accelerated ovarian development and increased fecundity. However, the physiological mechanism of begomoviruse-infected plants acting on the reproduction of the insect vector was unknown.
Biochemical and molecular properties of vitellogenin (Vg) and vitellin (Vt) were characterized in the MEAM1 whitefly. In addition, kinetics of Vt levels in ovary and Vg levels in hemolymph in different stages were detected using a sandwich ELISA. The level of hemolymph Vg increased rapidly after eclosion. A significantly higher level of hemolymph Vg and ovary Vt were observed in whiteflies feeding on virus-infected tobacco plants than those feeding on uninfected plants. In order to detect the levels of Vg mRNA transcription, complete vitellogenin (Vg) mRNA transcripts of 6474 bp were sequenced. Vg mRNA level in whiteflies feeding on virus-infected plants was higher than those feeding on uninfected plants. However, virus-infection of the whiteflies per se, as demonstrated using an artificial diet system, did not produce significant changes in Vg mRNA level.
In MEAM1 whitefly, increased levels of both vitellin and vitellogenin as well as increased transcription of Vg mRNA are associated with feeding on begomovirus-infected plants, thus providing a mechanism for accelerated vitellogenesis. We conclude that MEAM1 whitefly profits from feeding on begomovirus-infected plants for yolk protein synthesis and uptake, and thereby increases its fecundity. These results not only provide insights into the molecular and physiological mechanisms underlying the elevated reproduction of a whitefly species through its association with a begomovirus-infected plant, but also provide a better understanding of the molecular mechanisms related to whitefly reproduction.
An alternative strategy for inhibition of the cyclin dependent kinases in anti-tumor drug discovery is afforded through the substrate recruitment site on the cyclin positive regulatory subunit. Critical CDK substrates such as the Rb and E2F families must undergo cyclin groove binding before phosphorylation and hence inhibitors of this interaction also block substrate specific kinase activity. This approach offers the potential of generating highly selective and cell cycle specific CDK inhibitors and to reduce the inhibition of transcription mediated through CDK7 and 9, commonly observed with ATP competitive compounds. While highly potent peptide and small molecule inhibitors of CDK2/cyclin A, E substrate recruitment have been reported, little information has been generated on the determinants of inhibitor binding to the cyclin groove of the CDK4/cyclin D1 complex. CDK4/cyclin D is a validated anti-cancer drug target and continues to be widely pursued in the development of new therapeutics based on cell cycle blockade. We have therefore investigated the structural basis for peptide binding to its cyclin groove and have examined the features contributing to potency and selectivity of inhibitors. Peptidic inhibitors of CDK4/cyclin D of pRb phosphorylation have been synthesized, and their complexes with CDK4/cyclin D1 crystal structures have been generated. Based on available structural information, comparisons of the cyclin grooves of cyclin A2 and D1 are presented and provide insights into the determinants for peptide binding and the basis for differential binding and inhibition. In addition, a complex structure has been generated in order to model the interactions of the CDKI, p27KIP1, with cyclin D1. This information has been used shed light onto the endogenous inhibition of CDK4 and also to identify unique aspects of cyclin D1 and which can be exploited in the design of cyclin groove based CDK inhibitors. Peptidic and non-peptidic compounds have been synthesized in order to explore structure-activity relationship for binding to the cyclin D1 groove which to date has not been carried out in a systematic fashion. Collectively, the data presented provides new insights into how compounds can be developed that function as chemical biology probes to determine the cellular and anti-tumor effects of CDK inhibition. Furthermore, such compounds will serve as templates for structure-guided efforts to develop potential therapeutics based on selective inhibition of CDK4/cyclin D activity.
Salmonella enterica serovar Pullorum is a chicken-adapted pathogen, causing pullorum disease. Its strict host adaptation has been suspected to result in gene decay. To validate this hypothesis and identify the decayed genes, we sequenced the complete genome of S. Pullorum RKS5078. We found 263 pseudogenes in this strain and conducted functional analyses of the decayed genes.
To enhance the accuracy of radioactive seed implants in the head and neck, a digital model individual template, containing information simultaneously on needle pathway and facial features, was designed to guide implantation with CT imaging. Thirty-one patients with recurrent and local advanced malignant tumors of head and neck after prior surgery and radiotherapy were involved in this study. Before 125I implants, patients received CT scans based on 0.75mm thickness. And the brachytherapy treatment planning system (BTPS) software was used to make the implantation plan based on the CT images. Mimics software and Geomagic software were used to read the data containing CT images and implantation plan, and to design the individual template. Then the individual template containing the information of needle pathway and face features simultaneously was made through rapid prototyping (RP) technique. All patients received 125I seeds interstitial implantation under the guide of the individual template and CT. The individual templates were positioned easily and accurately, and were stable. After implants, treatment quality evaluation was made by CT and TPS. The seeds and dosages distribution (D90,V100,V150) were well meet the treatment requirement. Clinical practice confirms that this approach can facilitate easier and more accurate implantation.
Digital model; individual template; radioactive seeds; head and neck
Functional gastrointestinal disorders (FGIDs) are a group of conditions characterized by the dysfunction of the gastrointestinal (GI) tract. Although the specific pathogenesis of FGIDs is unclear, several theories have been proposed to explain the symptoms. Abnormal GI motility and visceral hypersensitivity have always been considered to be the main physiopathologic basis of FGIDs, and FGIDs related to psychomental disorders have also caused a major social concern. In recent years, a growing number of researches have proved that cytokines have a significant influence on GI motility, and the role of cytokines in FGIDs has aroused more and more attention. In this article, we discuss the interaction between immunoinflammation and FGIDs, and make an overview of current studies.
Cytokine; depression; functional gastrointestinal disorders; psychomental disorders
Anti-inflammatory effects of the aqueous extract of Hibiscus taiwanensis (AHT) were used in lipopolysaccharide (LPS-)stimulated mouse macrophage RAW264.7 cells and carrageenan (Carr-)induced mouse paw edema model. When RAW264.7 macrophages were treated with AHT together with LPS, a concentration-dependent inhibition of nitric oxide (NO), tumor necrosis factor (TNF-α), and prostaglandin E2 (PGE2) levels productions were detected. Western blotting revealed that AHT blocked protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and elevated heme oxygenase-1 (HO-1), significantly. In the animal test, AHT decreased the paw edema at the 4th and the 5th h after Carr administration, and it increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the paw tissue. We also demonstrated AHT decreased the NO, TNF-α, and PGE2 levels on the serum level at the 5th h after the Carr injection. Western blotting revealed that AHT decreased Carr-induced iNOS, and COX-2, and increased HO-1 expressions at the 5th h in the edema paw. These findings demonstrated that AHT has excellent anti-inflammatory activities in vitro and in vivo and thus it has great potential to be used as a source for natural health products.
Some species of the whitefly Bemisia tabaci complex cause tremendous losses to crops worldwide through feeding directly and virus transmission indirectly. The primary salivary glands of whiteflies are critical for their feeding and virus transmission. However, partly due to their tiny size, research on whitefly salivary glands is limited and our knowledge on these glands is scarce.
We sequenced the transcriptome of the primary salivary glands of the Mediterranean species of B. tabaci complex using an effective cDNA amplification method in combination with short read sequencing (Illumina). In a single run, we obtained 13,615 unigenes. The quantity of the unigenes obtained from the salivary glands of the whitefly is at least four folds of the salivary gland genes from other plant-sucking insects. To reveal the functions of the primary glands, sequence similarity search and comparisons with the whole transcriptome of the whitefly were performed. The results demonstrated that the genes related to metabolism and transport were significantly enriched in the primary salivary glands. Furthermore, we found that a number of highly expressed genes in the salivary glands might be involved in secretory protein processing, secretion and virus transmission. To identify potential proteins of whitefly saliva, the translated unigenes were put into secretory protein prediction. Finally, 295 genes were predicted to encode secretory proteins and some of them might play important roles in whitefly feeding.
The combined method of cDNA amplification, Illumina sequencing and de novo assembly is suitable for transcriptomic analysis of tiny organs in insects. Through analysis of the transcriptome, genomic features of the primary salivary glands were dissected and biologically important proteins, especially secreted proteins, were predicted. Our findings provide substantial sequence information for the primary salivary glands of whiteflies and will be the basis for future studies on whitefly-plant interactions and virus transmission.
In order to identify novel chemical classes of β-secretase (BACE-1) inhibitors, an alternative scoring protocol, Principal Component Analysis (PCA), was proposed to summarize most of the information from the original scoring functions and re-rank the results from the virtual screening against BACE-1.
Given a training set (50 BACE-1 inhibitors and 9950 inactive diverse compounds), three rank-based virtual screening methods, individual scoring, conventional consensus scoring and PCA, were judged by the hit number in the top 1% of the ranked list. The docking poses were generated by Surflex, five scoring functions (Surflex_Score, D_Score, G_Score, ChemScore, and PMF_Score) were used for pose extraction. For each pose group, twelve scoring functions (Surflex_Score, D_Score, G_Score, ChemScore, PMF_Score, LigScore1, LigScore2, PLP1, PLP2, jain, Ludi_1, and Ludi_2) were used for the pose rank. For a test set, 113,228 chemical compounds (Sigma-Aldrich® corporate chemical directory) were docked by Surflex, then ranked by the same three ranking methods motioned above to select the potential active compounds for experimental test.
For the training set, the PCA approach yielded consistently superior rankings compared to conventional consensus scoring and single scoring. For the test set, the top 20 compounds according to conventional consensus scoring were experimentally tested, no inhibitor was found. Then, we relied on PCA scoring protocol to test another different top 20 compounds and two low micromolar inhibitors (S450588 and 276065) were emerged through the BACE-1 fluorescence resonance energy transfer (FRET) assay.
The PCA method extends the conventional consensus scoring in a quantitative statistical manner and would appear to have considerable potential for chemical screening applications.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited disease leading to recurrent ischemic stroke and vascular dementia. Numerous mutations in the 23 exons of the NOTCH3 gene have been reported to cause CADASIL in Caucasian populations, but the full spectrum of genetic changes leading to this disease is yet to be known and, especially, very few reports are available on CADASIL in Asian populations.
Methods and Results
We genotyped members of a 5-generational Han Chinese family with CADASIL patients and identified an R133C mutation in the NOTCH3 gene. Clinical analysis demonstrated that the penetrance of the mutation was not complete. Five of the mutation carriers, not exposed to the known vascular risk factors, did not show any clinical feature of CADASIL, suggesting the importance of environmental factors to the development of this disease.
Members of a 5-generational Han Chinese family with CADASIL patients had an R133C mutation in the NOTCH3 gene but only individuals exposed to known vascular risk factors developed CADASIL.