The Toll-like receptor (TLR)-mediated NF-κB pathway is tightly controlled because overactivation may result in severe damage to the host, such as in the case of chronic inflammatory diseases and cancer. In mammals, sterile-alpha and armadillo motif-containing protein (SARM) plays an important role in negatively regulating this pathway. While Caenorhabditis elegans SARM is crucial for an efficient immune response against bacterial and fungal infections, it is still unknown whether Drosophila SARM participates in immune responses. Here, Litopenaeus vannamei SARM (LvSARM) was cloned and functionally characterized. LvSARM shared signature domains with and exhibited significant similarities to mammalian SARM. Real-time quantitative PCR analysis indicated that the expression of LvSARM was responsive to Vibrio alginolyticus and white spot syndrome virus (WSSV) infections in the hemocyte, gill, hepatopancreas and intestine. In Drosophila S2 cells, LvSARM was widely distributed in the cytoplasm and could significantly inhibit the promoters of the NF-κB pathway-controlled antimicrobial peptide genes (AMPs). Silencing of LvSARM using dsRNA-mediated RNA interference increased the expression levels of Penaeidins and antilipopolysaccharide factors, which are L.vannamei AMPs, and increased the mortality rate after V. alginolyticus infection. Taken together, our results reveal that LvSARM may be a novel component of the shrimp Toll pathway that negatively regulates shrimp AMPs, particularly Penaeidins and antilipopolysaccharide factors.
Mdm2 inhibits p53 transactivation by forming a p53-Mdm2 complex on chromatin. Upon DNA damage-induced complex disruption, such latent p53 can be activated, but in cells overexpressing Mdm2 because of a homozygous single nucleotide polymorphism at position 309 (T→G) of mdm2, the complex is highly stable and cannot be disrupted by DNA damage, rendering p53 inactive.
To determine whether the p53 response phenotype is influenced differentially in cells with variable mdm2 genotypes, we compared responses to DNA damage and targeted p53-Mdm2 complex disruption by Nutlin-3 in the following wild-type p53 human cancer cell lines: A875 and CCF-STTG-1 (G/G for mdm2 SNP309), SJSA-1 (mdm2 genomic amplification and T/T for mdm2 SNP309), MCF-7 (estrogen-induced Mdm2 overexpression and T/G for mdm2 SNP309), ML-1 and H460 (T/T for mdm2 SNP309), and K562 (p53-null and T/G for mdm2 SNP309). We also examined mdm2 gene-splicing patterns in these lines by cloning and sequencing analyses.
While Mdm2-overexpressing G/G cells were resistant to p53 activation by DNA damage, they were sensitive to Nutlin-3. Strikingly, the p53 G1 checkpoint in G/G cells was activated by Nutlin-3 but not by etoposide, whereas in other Mdm2-overexpressing cells, both drugs activated p53 and subsequent G1 arrest or apoptosis. cDNA clones lacking exons 5–9 were generated at a high frequency in cells overexpressing Mdm2.
Nutlin-3 and DNA damage distinguish a differential phenotype in human cancer cells with G/G mdm2 SNP309 from other Mdm2 overexpressers. Categorization of the Mdm2 isoforms produced and their influence on p53 activity will help in characterization and treatment development for different cancers.
p53; Mdm2; SNP309; Phenotype; Nutlin-3
Brain-derived neurotrophic factor (BDNF) has been associated with regulation of body weight and appetite. The goal of this study was to examine the interactions of a functional variant (rs6265) in the BDNF gene with dietary intake for obesity traits in the Boston Puerto Rican Health Study. BDNF rs6265 was genotyped in 1147 Puerto Rican adults and examined for association with obesity-related traits. Men (n = 242) with the GG genotype had higher BMI (P = 0.009), waist circumference (P = 0.002), hip (P = 0.002), and weight (P = 0.03) than GA or AA carriers (n = 94). They had twice the risk of being overweight (BMI ≥ 25) relative to GA or AA carriers (OR = 2.08, CI = 1.02–4.23, and P = 0.043). Interactions between rs6265 and polyunsaturated fatty acids (PUFA) intake were associated with BMI, hip, and weight, and n-3 : n-6 PUFA ratio with waist circumference in men. In contrast, women (n = 595) with the GG genotype had significantly lower BMI (P = 0.009), hip (P = 0.029), and weight (P = 0.027) than GA or AA carriers (n = 216). Women with the GG genotype were 50% less likely to be overweight compared to GA or AA carriers (OR = 0.05, CI = 0.27–0.91, and P = 0.024). In summary, BDNF rs6265 is differentially associated with obesity risk by sex and interacts with PUFA intake influencing obesity traits in Boston Puerto Rican men.
The identification of new virus strains is important for the study of infectious disease, but current (or existing) molecular biology methods are limited since the target sequence must be known to design genome-specific PCR primers. Thus, we developed a new method for the discovery of unknown viruses based on the cDNA - random amplified polymorphic DNA (cDNA-RAPD) technique. Getah virus, belonging to the family Togaviridae in the genus Alphavirus, is a mosquito-borne enveloped RNA virus that was identified using the Virus-Discovery-cDNA RAPD (VIDISCR) method.
A novel Getah virus was identified by VIDISCR from suckling mice exposed to mosquitoes (Aedes albopictus) collected in Yunnan Province, China. The non-structural protein gene, nsP3, the structural protein gene, the capsid protein gene, and the 3'-untranslated region (UTR) of the novel Getah virus isolate were cloned and sequenced. Nucleotide sequence identities of each gene were determined to be 97.1–99.3%, 94.9–99.4%, and 93.6–99.9%, respectively, when compared with the genomes of 10 other representative strains of Getah virus.
The VIDISCR method was able to identify known virus isolates and a novel isolate of Getah virus from infected mice. Phylogenetic analysis indicated that the YN08 isolate was more closely related to the Hebei HB0234 strain than the YN0540 strain, and more genetically distinct from the MM2021 Malaysia primitive strain.
Getah virus; Identification; Virus-Discovery; cDNA RAPD
There is a recent emergence of interest in the genes involved in gametic recognition as drivers of reproductive isolation. The recent population genomic sequencing of two species of sexually primitive yeasts (Liti G, Carter DM, Moses AM, Warringer J, Parts L, James SA, Davey RP, Roberts IN, Burt A, Koufopanou V et al. [23 co-authors]. 2009. Population genomics of domestic and wild yeasts. Nature 458:337–341.) has provided data for systematic study of the roles these genes play in the early evolution of sex and speciation. Here, we discovered that among genes encoding cell surface proteins, the sexual adhesin genes have evolved significantly more rapidly than others, both within and between Saccharomyces cerevisiae and its closest relative S. paradoxus. This result was supported by analyses using the PAML pairwise model, a modified McDonald–Kreitman test, and the PAML branch model. Moreover, using a combination of a new statistic of neutrality, an information theory–based measure of evolutionary variability, and functional characterization of amino acid changes, we found that a higher proportion of amino acid changes are fixed in the sexual adhesins than in other proteins and a greater proportion of the fixed amino acid changes either between the two species or the two subgroups of S. paradoxus are functionally dissimilar or radically different. These results suggest that the accelerated evolution of sexual adhesin genes may facilitate speciation, or incipient speciation, and promote sexual selection in general.
sex genes; cell surface proteins; yeast; modified McDonald–Kreitman test; evolutionary variability; adaptive evolution
Myeloid differentiation factor 88 (MyD88) is a universal and essential signaling protein in Toll-like receptor/interleukin-1 receptor-induced activation of nuclear factor-kappa B. In this study, two MyD88 protein variants (LvMyD88 and LvMyD88-1) were identified in Litopenaeus vannamei. The LvMyD88 cDNA is 1,848 bp in length and contains an open reading frame (ORF) of 1,428 bp, whereas the LvMyD88-1 cDNA is 1,719 bp in length and has an ORF of 1,299 bp. Both variants encode proteins with death and Toll/interleukin-1 receptor domains and share 91% sequence identity. In healthy L. vannamei, the LvMyD88 genes were highly expressed in hemocytes but at a low level in the hepatopancreas. The LvMyD88s expression was induced in hemocytes after challenge with lipopolysaccharide, CpG-ODN2006, Vibrio parahaemolyticus, Staphyloccocus aureus, and white spot syndrome virus, but not by poly I∶C. Overexpression of LvMyD88 and LvMyD88-1 in Drosophila Schneider 2 cells led to activation of antimicrobial peptide genes and wsv069 (ie1), wsv303, and wsv371. These results suggested that LvMyD88 may play a role in antibacterial and antiviral response in L. vannamei. To our knowledge, this is the first report on MyD88 in shrimp and a variant of MyD88 gene in invertebrates.
The histone H3K27 demethylases UTX and JMJD3 are important regulatory factors that modulate gene expression by altering the physical state of chromatin. Previous studies have indicated an abnormal H3K27 methylation status in carcinogenesis. We therefore investigated the expression patterns of UTX and JMJD3 in renal cell carcinoma (RCC) and their roles in cancer development.
The mRNA expression levels of the UTX and JMJD3 genes were determined in cancer tissues and adjacent normal tissues in 36 patients with primary RCC, using quantitative real-time-polymerase chain reaction. The UTX and JMJD3 protein contents were measured by western blotting and immunohistochemical analysis.
UTX and JMJD3 transcripts were significantly increased in cancer tissues compared to normal tissues (P < 0.05). mRNA levels of the inhibitor of cyclin-dependent kinases 4 and 6 p16INK4a were also increased in cancer tissues (P < 0.001). Western blotting indicated that levels of both demethylases were increased in cancer tissues. The level of tri-methylated H3K27 (H3K27me3) was lower in cancer tissues compared to normal tissues, but expression of the H3K27 methyltransferase EZH2 was increased (P < 0.05). These results suggest that the two H3K27 demethylases may play critical roles in the regulation of H3K27 methylation status in RCC. Immunohistochemical analysis confirmed that UTX and JMJD3 expression were upregulated in cancer tissues compared to adjacent tissues.
This study demonstrated that UTX and JMJD3 were upregulated in cancer tissues, suggesting that they may be involved in the development of primary RCC. The potential roles of H3K27 demethylases as biomarkers in the early diagnosis of RCC need to be further explored.
Renal cell carcinoma; Histone H3K27 demethylase; UTX; JMJD3; Epigenetics
Hepatocyte death and proliferation contribute to hepatocellular carcinoma development following carcinogen exposure or chronic liver inflammation. However, the role and the molecular targets of hepatocyte death in relation to compensatory proliferation remain to be fully characterized. In this study, we investigated the role of PUMA, a BH3-only protein important for both p53-dependent and -independent apoptosis, in a diethylnitrosamine (DEN)-induced liver carcinogenesis model. PUMA deficiency significantly decreased the multiplicity and size of liver tumors. DEN treatment induced p53-independent PUMA expression, PUMA-dependent hepatocyte death, and compensatory proliferation. Furthermore, inhibition or deletion of JNK1 abrogated PUMA induction, hepatocyte death, and compensatory proliferation. These results provide direct evidence that JNK1/PUMA-dependent apoptosis promotes chemical hepatocarcinogenesis via compensatory proliferation, and suggest apoptotic inducers as potential therapeutic targets in liver injury and cancer.
PUMA; JNK1; liver cancer; apoptosis; proliferation
Background and Purpose
Gait impairment is common in the elderly, especially those with stroke and white matter hyperintensities (WMH) on conventional brain MRI. Diffusion Tensor Imaging (DTI) is more sensitive to white matter damage than conventional MRI. The relationship between DTI measures and gait has not been previously evaluated. Our purpose was to investigate the relationship between the integrity of white matter in the corpus callosum as determined by DTI and quantitative measures of gait in the elderly.
One hundred seventy-three participants of a community-dwelling elderly cohort had neurological and neuropsychological examinations and brain MRI. Gait function was measured by Tinetti gait (0-12), balance (0-16) and total (0-28) scores. DTI assessed Fractional Anisotropy in the genu and splenium of the corpus callosum. Conventional MRI was used to evaluate for brain infarcts and WMH volume.
Participants with abnormal gait had low fractional anisotropy in the genu of the corpus callosum but not the splenium. Multiple regressions analyses showed an independent association between these genu abnormalities and all three Tinetti scores (p <0.001). This association remained significant after adding MRI infarcts and WMH volume to the analysis.
The independent association between quantitative measures of gait function and DTI findings shows that white matter integrity in the genu of corpus callosum is an important marker of gait in the elderly. DTI analyses of white matter tracts in brain and spinal cord may improve knowledge about the pathophysiology of gait impairment and help target clinical interventions.
Gait; Mobility; MRI; Diffusion; Diffusion-Weighted Imaging; Epidemiology; Magnetic Resonance; Neuroradiology; White Matter Disease
A number of studies have reported on the effects of iron supplementation in low birth weight infants; however, no systematic review of the available evidence has been conducted to date. Hence, we performed a systematic review of the literature to examine the effects of iron supplementation on hematologic iron status, growth, neurodevelopment, and adverse effects in low birth weight/premature infants.
We searched the Cochrane Library, Medline, and PubMed for articles reporting on the effects of iron supplementation in low weight infants. The following search terms were used: “preterm born infant(s)/children”; “preterm infants”; “prematurely born children” “weight less than 1500 g at birth”; “born prematurely”; “low birth weight infant(s)”; “infants born preterm”; “prematurity”; “small-for-gestational age”; “very small gestational age infants”; “iron supplementation”; “iron intake”; “iron supplements”; “ferric and/or ferrous compounds”; and “ferrous sulphate/fumarate/sulfate”.
A total of 15 studies were identified and included in the systematic review. Supplemental iron was given orally or as an iron-fortified formula in 14/15 studies. The duration of treatment ranged from 1 week to 18 months. Iron supplementation significantly increased hematologic measures of iron status (including hemoglobin, hematocrit, serum ferritin) relative to placebo or over time in most studies. All controlled studies that examined iron-deficiency anemia (IDA)/ID reported a decreased prevalence of IDA/ID with iron supplementation. Dose dependent decreases in the prevalence of IDA/ID were reported in several studies. Of the 5 studies reporting on growth, none found any significant effect on growth-related parameters (length, height, weight, and head circumference). Only 2 studies reported on neurodevelopment; no marked effects were reported. There were no consistently reported adverse effects, including oxidative stress, inhibited nutrient absorption, morbidity, or the requirement for blood transfusion.
The available data suggest that iron supplementation increases the levels of hematologic indicators of iron status and reduces the prevalence of IDA/ID in low birth weight/premature infants. There is insufficient evidence to make a definitive statement regarding the effects of iron supplementation on growth, neurodevelopment, or the occurrence of adverse effects in low birth weight/premature infants.
Anemia; Infant; Iron deficiency; Iron supplementation; Low birth weight
Depression is associated with an increase in the incidence of type 2 diabetes, but the mechanism is unclear. We aimed to study the relationship between depression and glycemic intake in the elderly, and examine whether antidepressant use modified this relationship.
Design, Setting and Participants
We evaluated 976 homebound elders in a cross-sectional study. Depressed was defined by having a Center for Epidemiological Studies Depression (CES-D) score ≥ 16. Antidepressant use was documented. Glycemic index (GI), Glycemic load (GL), and fasting blood insulin levels were measured.
Depressed elders had slightly higher GI (Mean ± SD: 55.8 ± 3.8 vs. 55.1 ± 3.7, P = 0.003) and higher insulin levels (Median: 84.0 vs. 74.4 pmole/ml, P = 0.05) than non-depressed elders. Depressed elders receiving antidepressants, primarily selective serotonin reuptake inhibitors (SSRI), had lower GI (Mean ± SD: 55.1 ± 4.7 vs. 56.2 ± 3.4, P = 0.002) and GL (Median: 170.3 vs. 6826.3, P = 0.03) than those not taking antidepressants. After adjusting for potential confounding variables, GI remained positively associated with depression (β = + 0.65, SE = 0.28, P = 0.02); logarithm of GL was positively associated with depression (β = + 0.33, SE = 0.17, P = 0.05) and negatively associated with antidepressant use (β = − 0.54, SE = 0.18, P = 0.003).
Prospective studies are needed to examine whether high glycemic intake is a mediating factor between late life depression and the risk of type 2 diabetes.
It has been known for decades that human Lyme disease is caused by the three spirochete species Borrelia burgdorferi, Borrelia afzelii, and Borrelia garinii. Recently, Borrelia valaisiana, Borrelia spielmanii, and Borrelia bissettii have been associated with Lyme disease. We report the complete genome sequences of B. valaisiana VS116, B. spielmanii A14S, and B. bissettii DN127.
Lipin-1 proteins are phosphatidic acid phosphatases catalyzing the conversion from phosphatidic acid to diacylglycerol. Two alternative splicing isoforms, lipin-1α and -1β, are localized at different subcellular compartments. A third splicing isoform, lipin-1γ was recently cloned and its subcellular localization is unknown. Here, we demonstrate that lipin-1γ is localized to lipid droplets, an association mediated by a hydrophobic, lipin-1γ-specific domain. Additional expression of lipin-1γ altered lipid droplet morphology without affecting the triacylglycerol level. In human tissues, lipin-1γ is the main lipin-1 isoform expressed in normal human brain, suggesting a specialized role in regulating brain lipid metabolism.
Lipin; phosphatidic acid phosphatase; lipid droplets; brain
Human Lyme disease is commonly caused by several species of spirochetes in the Borrelia genus. In Eurasia these species are largely Borrelia afzelii, B. garinii, B. burgdorferi, and B. bavariensis sp. nov. Whole-genome sequencing is an excellent tool for investigating and understanding the influence of bacterial diversity on the pathogenesis and etiology of Lyme disease. We report here the whole-genome sequences of four isolates from two of the Borrelia species that cause human Lyme disease, B. afzelii isolates ACA-1 and PKo and B. garinii isolates PBr and Far04.
Characterization of novel proteins in maternal serum derived from mothers carrying Down syndrome (DS) fetuses.
Material and methods
Based on last comparative proteomic analysis, five significant differences of expressed proteins in serum from four groups have been confirmed by ELISA. DAVID and GeneGo MetaCore were used to bioinformatically analyze candidate protein markers.
The serum levels of ceruloplasmin (CP) and complement factor B (CFB) were significantly increased in mother carried DS fetuses (346.5 ng/ml and 466.8 ng/ml vs. 248.6 ng/ml and 293.5 ng/ml, p< 0.05). Twenty-nine proteins were mainly categorized into binding, catalytic activity and enzyme regulator activity proteins, and their biological roles were involved in biological regulation, metabolic processes, cellular processes, and response to stimuli. The immune response alternative complement pathway was the most significant GeneGo Pathway related to DS.
These 29 proteins have relations with the development of Down syndrome, especially CP and CFB play more important roles.
Down syndrome; proteomic; serum; bioinformatics; biomarkers; prenatal diagnosis
The role of p53 in tissue protection is not well understood. Loss of p53 blocks apoptosis in the intestinal crypts following irradiation, but paradoxically accelerates gastrointestinal (GI) damage and death. PUMA and p21 are the major mediators of p53-dependent apoptosis and cell cycle checkpoints, respectively. To better understand these two arms of p53 response in radiation-induced GI damage, we compared animal survival, as well as apoptosis, proliferation, cell cycle progression, DNA damage, and regeneration in the crypts of WT, p53 KO, PUMA KO, p21 KO, and p21/PUMA double KO (DKO) mice in a whole body irradiation model. Deficiency in p53 or p21 led to shortened survival but accelerated crypt regeneration associated with massive non-apoptotic cell death. Non-apoptotic cell death is characterized by aberrant cell cycle progression, persistent DNA damage, rampant replication stress and genome instability. PUMA deficiency alone enhanced survival and crypt regeneration by blocking apoptosis, but failed to rescue delayed non-apoptotic crypt death or shortened survival in p21 KO mice. These studies help better understand p53 functions in tissue injury and regeneration, and potentially improve strategies to protect or mitigate intestinal damage induced by radiation.
p53; p21; PUMA; cell cycle arrest; apoptosis; irradiation; small intestine; stem cells
The mycobactin siderophore system is present in many Mycobacterium species, including M. tuberculosis and other clinically relevant mycobacteria. This siderophore system is believed to be utilized by both pathogenic and nonpathogenic mycobacteria for iron acquisition in both in vivo and ex vivo iron-limiting environments, respectively. Several M. tuberculosis genes located in a so-called mbt gene cluster have been predicted to be required for the biosynthesis of the core scaffold of mycobactin based on sequence analysis. A systematic and controlled mutational analysis probing the hypothesized essential nature of each of these genes for mycobactin production has been lacking. The degree of conservation of mbt gene cluster orthologs remains to be investigated as well. In this study, we sought to conclusively establish whether each of nine mbt genes was required for mycobactin production and to examine the conservation of gene clusters orthologous to the M. tuberculosis mbt gene cluster in other bacteria. We report a systematic mutational analysis of the mbt gene cluster ortholog found in Mycobacterium smegmatis. This mutational analysis demonstrates that eight of the nine mbt genes investigated are essential for mycobactin production. Our genome mining and phylogenetic analyses reveal the presence of orthologous mbt gene clusters in several bacterial species. These gene clusters display significant organizational differences originating from an intricate evolutionary path that might have included horizontal gene transfers. Altogether, the findings reported herein advance our understanding of the genetic requirements for the biosynthesis of an important mycobacterial secondary metabolite with relevance to virulence.
Phosphorylation of the insulin receptor substrates (Irs) on serine residues—typified by Ser307 of rodent Irs1—is thought to mediate insulin resistance. To determine whether Ser307 negatively regulates Irs1 in vivo, we generated knock-in mice in which Ser307 (human Ser312) was replaced with alanine (A/A). Unexpectedly, A/A mice that were fed a high fat diet developed more severe insulin resistance than control mice, accompanied by enhanced pancreatic compensation and impaired muscle insulin signaling. Chow-fed mice whose livers lacked Irs2, but retained a single knock-in allele (A/lox::LKO2) were profoundly insulin resistant (versus +/lox::LKO2 mice), and their hepatocytes showed impaired insulin signaling ex vivo. Similarly, mutant A307 Irs1 adenovirus only partially restored the response to injected insulin in mice lacking hepatic Irs1 and Irs2. Thus, contrary to the results of cell-based experiments, Ser307 in mice is a positive regulatory site that moderates the severity of insulin resistance by maintaining proximal insulin signaling.
Plasmodium falciparum is the protozoan parasite primarily responsible for more than one million malarial deaths, annually, and is developing resistance to current therapies. Throughout its lifespan, the parasite is subjected to oxidative attack, so Plasmodium antioxidant defences are essential for its survival and are targets for disease control.
To further understand the molecular aspects of the Plasmodium redox system, we solved 4 structures of Plasmodium peroxiredoxins (Prx). Our study has confirmed PvTrx-Px1 to be a hydrogen peroxide (H2O2)-sensitive peroxiredoxin. We have identified and characterized the novel toroid octameric oligomer of PyTrx-Px1, which may be attributed to the interplay of several factors including: (1) the orientation of the conserved surface/buried arginine of the NNLA(I/L)GRS-loop; and (2) the C-terminal tail positioning (also associated with the aforementioned conserved loop) which facilitates the intermolecular hydrogen bond between dimers (in an A-C fashion). In addition, a notable feature of the disulfide bonds in some of the Prx crystal structures is discussed. Finally, insight into the latter stages of the peroxiredoxin reaction coordinate is gained. Our structure of PyPrx6 is not only in the sulfinic acid (RSO2H) form, but it is also with glycerol bound in a way (not previously observed) indicative of product binding.
The structural characterization of Plasmodium peroxiredoxins provided herein provides insight into their oligomerization and product binding which may facilitate the targeting of these antioxidant defences. Although the structural basis for the octameric oligomerization is further understood, the results yield more questions about the biological implications of the peroxiredoxin oligomerization, as multiple toroid configurations are now known. The crystal structure depicting the product bound active site gives insight into the overoxidation of the active site and allows further characterization of the leaving group chemistry.
Lyme disease is the most common tick-borne human illness in North America. In order to understand the molecular pathogenesis, natural diversity, population structure and epizootic spread of the North American Lyme agent, Borrelia burgdorferi sensu stricto, a much better understanding of the natural diversity of its genome will be required. Towards this end we present a comparative analysis of the nucleotide sequences of the numerous plasmids of B. burgdorferi isolates B31, N40, JD1 and 297. These strains were chosen because they include the three most commonly studied laboratory strains, and because they represent different major genetic lineages and so are informative regarding the genetic diversity and evolution of this organism. A unique feature of Borrelia genomes is that they carry a large number of linear and circular plasmids, and this work shows that strains N40, JD1, 297 and B31 carry related but non-identical sets of 16, 20, 19 and 21 plasmids, respectively, that comprise 33–40% of their genomes. We deduce that there are at least 28 plasmid compatibility types among the four strains. The B. burgdorferi ∼900 Kbp linear chromosomes are evolutionarily exceptionally stable, except for a short ≤20 Kbp plasmid-like section at the right end. A few of the plasmids, including the linear lp54 and circular cp26, are also very stable. We show here that the other plasmids, especially the linear ones, are considerably more variable. Nearly all of the linear plasmids have undergone one or more substantial inter-plasmid rearrangements since their last common ancestor. In spite of these rearrangements and differences in plasmid contents, the overall gene complement of the different isolates has remained relatively constant.
Macrophages are specialized to detect and destroy intracellular microbes and yet a number of pathogens have evolved to exploit this hostile niche. Here we demonstrate that the obligate intracellular parasite Toxoplasma gondii disarms macrophage innate clearance mechanisms by secreting a serine threonine kinase called ROP18, which binds to and phosphorylates immunity-related GTPases (IRGs). Substrate profiling of ROP18 revealed a preference for a conserved motif within switch region I of the GTPase domain, a modification predicted to disrupt IRG function. Consistent with this, expression of ROP18 was both necessary and sufficient to block recruitment of Irgb6, which was in turn required for parasite destruction. ROP18 phosphorylation of IRGs prevented clearance within inflammatory monocytes and IFN-γ-activated macrophages, conferring parasite survival in vivo and promoting virulence. IRGs are implicated in clearance of a variety of intracellular pathogens, suggesting that other virulence factors may similarly thwart this innate cellular defense mechanism.
There are currently more than 38.9 million people over the age of 65 in the United States. Up to 3.6 million of these people are considered housebound and in need of home-based care. Although homebound status is not defined specifically, with a broad range of disability levels, it is evident that people who are homebound suffer from a multitude of medical and psychiatric illnesses. This review examines the current literature to identify the specific physical and psychiatric factors most responsible for the elderly becoming and remaining housebound. The homebound elderly suffer from metabolic, cardiovascular, cerebrovascular, and musculoskeletal diseases, as well as from cognitive impairment, dementia and depression, at higher rates than the general elderly population. The information in this review will explain the specific types of care the homebound population need, and discuss the care that could help ease their suffering and delay their entry into a nursing home or hospital.
homebound; psychiatric; medically
Background: Misfolded protein aggregates are recruited to the aggresome by a protein complex consisting of histone deacetylase 6 (HDAC6).
Results: The ubiquitin-binding domain (ZnF-UBP) of HDAC6 binds to ubiquitin C termini generated by ataxin-3.
Conclusion: The exposure of ubiquitin C termini within protein aggregates enables HDAC6 recognition.
Significance: This study provides the role of HDAC6 in aggresome formation and suggests a novel ubiquitin-mediated signaling pathway.
The aggresome pathway is activated when proteasomal clearance of misfolded proteins is hindered. Misfolded polyubiquitinated protein aggregates are recruited and transported to the aggresome via the microtubule network by a protein complex consisting of histone deacetylase 6 (HDAC6) and the dynein motor complex. The current model suggests that HDAC6 recognizes protein aggregates by binding directly to polyubiquitinated proteins. Here, we show that there are substantial amounts of unanchored ubiquitin in protein aggregates with solvent-accessible C termini. The ubiquitin-binding domain (ZnF-UBP) of HDAC6 binds exclusively to the unanchored C-terminal diglycine motif of ubiquitin instead of conjugated polyubiquitin. The unanchored ubiquitin C termini in the aggregates are generated in situ by aggregate-associated deubiquitinase ataxin-3. These results provide structural and mechanistic bases for the role of HDAC6 in aggresome formation and further suggest a novel ubiquitin-mediated signaling pathway, where the exposure of ubiquitin C termini within protein aggregates enables HDAC6 recognition and transport to the aggresome.
Deubiquitination; Protein Aggregation; Protein Structure; Protein-Protein Interactions; Ubiquitin; Aggresome; Ataxin-3
The target-controlled infusion-III (SLOG/TCI-III) system was derived from a model set up by the local pediatric population for target control infusion of propofol.
The current study aimed at evaluating the difference between target concentrations of propofol and performance, which was measured using the SLOG/TCI-III system in children. Thirty children fulfilling the I-II criteria according to American Society of Anesthesiology were enrolled in the study. The target plasma concentration of propofol was fed into the SLOG/TCI-III system and compared with the measured concentrations of propofol. Blood samples were collected and analyzed by high performance liquid chromatography with fluorescence detector. The performance error (PE) was determined for each measured blood propofol concentration. The performances of the TCI-III system were determined by the median performance error (MDPE), the median absolute performance error (MDAPE), and Wobble (the median absolute deviation of each PE from the MDPE), respectively.
Concentration against target concentration showed good linear correlation: concentration = 1.3428 target concentration - 0.2633 (r = 0.8667). The MDPE and MDAPE of the pediatric system were 10 and 22%, respectively, and the median value for Wobble was 24%. MDPE and MDAPE were less than 15 and 30%, respectively.
The performance of TCI-III system seems to be in the accepted limits for clinical practice in children.
Propofol; plasma concentration; high performance liquid chromatography; drug delivery system, pediatric, evaluation
To evaluate clinical value of a new self-sequential longitudinal reference intervals of thyroid function during pregnancy.
Material and methods
We established two different series of reference intervals: self-sequential longitudinal reference intervals (SLRI) and general gestation-specific reference intervals (GSRI). For SLRI, the serum of 301 cases were collected five times in every case throughout the gestation. For GSRI, A total of 1455 subjects included in the study. We collected the serum respectively at various trimesters. We used TSH of both reference intervals to screen 1744 pregnant women, and compared the percentage of potential misclassification.
Both SLRI and GSRI differed substantially from that for non-pregnant women (p < 0.05). There are similar fluctuations of serum TSH, FT4 and TPO-Ab during normal pregnancy. Although there were no significant differences in most reference intervals between SLRI and GSRI. But the IQR of SLRI were usually smaller than GSRI , especially in 1st trimester. Two hundred and fifty two women (14.4%) at various trimesters whose serum TSH concentration was within SLRI would be misclassified, while 23 women (1.3%) with a TSH concentration outside limit would not be identified. 0.11-3.84% women would got thyroid diseases during pregnancy. Subclinical hypothyroidism is most common maternal thyroid disorders.
The SLRI can reflected the changes of thyroid function realistically, and can be used to decrease the percentage of potential misclassification of thyroid dysfunction during pregnancy. Screening for thyroid dysfunction of pregnant women is recommended and important.
pregnancy; thyroid hormones; reference intervals; self-sequential; outcome