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Upside Down Jumping Spider

This jumping spider was personable and very easy to photograph as it was willing to sit still, facing me.




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Histologic Chorioamnionitis Is Associated With Reduced Risk of Late-Onset Sepsis in Preterm Infants

Chorioamnionitis is associated with preterm birth and an increased risk of common adverse outcomes of prematurity, including early-onset sepsis and neurodevelopmental impairment. The effect of chorioamnionitis on postnatal immune function and risk of late-onset infection is unknown.

Chorioamnionitis, which complicates many preterm births, is independently associated with a significantly reduced risk of late-onset sepsis in preterm infants. The findings suggest that chorioamnionitis may modulate the development of postnatal immunity in a clinically significant manner. (Read the full article)




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Preeclampsia and Retinopathy of Prematurity in Preterm Births

Preterm infants are at a high risk for retinopathy of prematurity (ROP). Several postnatal factors are well known to be associated with ROP. However, the relationships between antenatal or maternal risk factors and ROP are poorly understood.

This study used a large cohort database to study the influence of maternal gestational hypertension and preeclampsia on ROP in preterm infants. The results showed that preeclampsia, but not gestational hypertension, was associated with a reduced risk of ROP in preterm births. (Read the full article)




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Adherence to PALS Sepsis Guidelines and Hospital Length of Stay

Adherence to Pediatric Advanced Life Support resuscitation guidelines for children with sepsis is low; however, few studies have been conducted in the tertiary care emergency department setting.

Adherence to septic shock guidelines in a tertiary care pediatric emergency department is low. Adherence to fluid guidelines and the entire PALS algorithm was associated with a shorter hospital length of stay. (Read the full article)




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Probiotic Effects on Late-onset Sepsis in Very Preterm Infants: A Randomized Controlled Trial

Late-onset sepsis is a frequent complication of prematurity, contributing to morbidity and mortality. Although evidence is accumulating that administration of probiotics to very preterm infants reduces necrotizing enterocolitis (NEC) and all-cause mortality, the effect on late-onset sepsis is less clear.

The probiotic combination Bifidobacterium infantis, Streptococcus thermophilus, and Bifidobacterium lactis reduced NEC in very preterm infants, but not mortality or late-onset sepsis. Probiotics may be of greatest global value in neonatal settings with high rates of NEC. (Read the full article)




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Stratification of Risk of Early-Onset Sepsis in Newborns >=34 Weeks' Gestation

The management of term and near-term newborns suspected of early-onset sepsis, particularly when they are not clearly symptomatic, remains controversial. Methods for quantifying risk that combine maternal factors with a newborn's evolving clinical examination have been lacking.

This study provides a method for predicting risk of early-onset sepsis. It combines maternal risk factors with objective measures of a newborn's clinical examination and places newborns into 3 risk groups (treat empirically, observe and evaluate, and continued observation). (Read the full article)




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Genome-Wide Expression Profiles in Very Low Birth Weight Infants With Neonatal Sepsis

Rapid and reliable tools for the diagnosis of neonatal sepsis are still unavailable. No single biomarker studied has yielded conclusive results. Genome-wide expression profiles (GWEPs) have been successfully determined for the diagnosis of sepsis in pediatric and adult populations.

GWEPs are described for the first time in very low birth weight infants with proven bacterial sepsis. Our results suggest that GWEPs could be used for early discrimination of septic newborn versus nonseptic infants. (Read the full article)




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Role of Guidelines on Length of Therapy in Chorioamnionitis and Neonatal Sepsis

Chorioamnionitis (CAM) is a major risk factor for early-onset neonatal sepsis. The Committee on the Fetus and Newborn recommends extending the duration of antimicrobial therapy in neonates exposed to CAM and intrapartum antibiotics if laboratory data are abnormal, even if culture results are sterile.

When managed by using a strategy similar to recent Committee on the Fetus and Newborn guidelines, a large number of term and late-preterm infants exposed to CAM who had sterile blood culture findings were treated with prolonged antibiotic therapy, subjected to additional invasive procedures, and had prolonged hospitalization. (Read the full article)




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Presepsin for the Detection of Late-Onset Sepsis in Preterm Newborns

Early diagnosis of LOS in preterm infants may be challenging because of the questionable accuracy of blood culture and the common markers of infections, such as C-reactive protein and procalcitonin.

Our study demonstrated for the first time that P-SEP is an accurate biomarker for the diagnosis of LOS in preterm infants and might contribute to the monitoring of infant response to therapeutic interventions. (Read the full article)




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Early Onset Neonatal Sepsis: The Burden of Group B Streptococcal and E. coli Disease Continues

Barbara J. Stoll
May 1, 2011; 127:817-826
ARTICLES




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Late-Onset Sepsis in Very Low Birth Weight Neonates: The Experience of the NICHD Neonatal Research Network

Barbara J. Stoll
Aug 1, 2002; 110:285-291
ARTICLES




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Redden Lodge and Forest Campsites Closed

To limit the potential spread of the Coronavirus, the Delaware Forest Service is announcing the following actions, effective immediately: The Lodge at Redden State Forest will be closed to the public until further notice. All campsites at Redden and Blackbird State Forests will be closed to the public until further notice. All large gatherings (>25 people) scheduled for any of the State Forests will be cancelled. State Forests will remain open to the general public for the time being for outdoor activities such as hiking, bird watching, horseback riding, etc.



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  • state forest camping

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Coronavirus pandemic turns travel plans upside down! Check how cruises, hotels, flights are impacted

However, the FICCI report indicates that cruise bookings for countries like Thailand, Singapore and Malaysia have registered considerable cancellations already.




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Partly Cloudy and Breezy and 42 F at Poughkeepsie, Dutchess County Airport, NY


Winds are from the West at 20.7 gusting to 34.5 MPH (18 gusting to 30 KT). The pressure is 1009.0 mb and the humidity is 41%. The wind chill is 33. Last Updated on May 9 2020, 11:53 am EDT.




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Leipsic, Rodewald draw NHL's ire over comments

Capitals forward Brendan Leipsic and Panthers prospect Jack Rodewald were both condemned by the NHL over "misogynistic and reprehensible" comments made on social media.




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Caps place Leipsic on waivers after comments

The Washington Capitals placed forward Brendan Leipsic on waivers for the purpose of terminating his contract.




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બુટલેગરને છાવરતા PSIને સસ્પેન્ડ નહીં કરાય તો બુધવારે બનાસકાંઠા બંધની ચિંમકી

પાલનપુરઃ ગુજરાત ભરમાં ક્ષત્રિય ઠાકોર સેના દ્વારા વ્યસનમુક્તિ અભિયાન ચલાવવામાં આવી રહ્યુ છે.થોડાક દિવસ અગાઉ બનાસકાંઠાના ક્ષત્રીય ઠાકોર સેના દ્વારા વડગામ તાલુકાના સમશેરપુરા ગામમાં જનતા રેડ કરવામાં આવી હતી. જે દરમિયાન પોલીસે ક્ષત્રીય ઠાકોર સેનાના 12 જેટલા કાર્યકરોની અટકાયત કરી હતી.જેને લઈને આજે અલ્પેશ ઠાકોરે પાલનપુર સર્કિટ હાઉસ પહોંચ્યા હતા અને પત્રકારોને સંબોધ્યા હતા.




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Paddelberg Topsite Script Insecure Cookie

Paddelberg Topsite Script version 1.2.3 suffers from an authentication bypass vulnerability due to insecure cookie handling.




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psibrute.com.txt

This DCL script abuses the old psi_mail trick on VAX/VMS systems to remotely find valid users.




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Upside-Down Apple-Pecan-Raisin Pie

From Nov 2009 Southern Living magazine. -- posted by Bren in LR




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Corona: What Autopsies Can Reveal about COVID-19

Pathologists are eager to quickly conduct autopsies on as many COVID-19 victims as possible. They aim to determine who is at greatest risk from the virus and what damage it causes inside the body. Initial results are already available.




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Don’t Miss: US on coronavirus, quake escape and the upside of slowdown

This week, listen as the US debates covid-19, play a struggling survivor of an earthquake-torn city and discover how the planet gains from human progress slowing down




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Health Tip: Be Alert for Signs of Preeclampsia

Title: Health Tip: Be Alert for Signs of Preeclampsia
Category: Health News
Created: 5/3/2012 8:05:00 AM
Last Editorial Review: 5/3/2012 12:00:00 AM




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Health Tip: Protect Yourself From Sepsis

Title: Health Tip: Protect Yourself From Sepsis
Category: Health News
Created: 4/30/2019 12:00:00 AM
Last Editorial Review: 4/30/2019 12:00:00 AM




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Romo1-Derived Antimicrobial Peptide Is a New Antimicrobial Agent against Multidrug-Resistant Bacteria in a Murine Model of Sepsis

ABSTRACT

To overcome increasing bacterial resistance to conventional antibiotics, many antimicrobial peptides (AMPs) derived from host defense proteins have been developed. However, there are considerable obstacles to their application to systemic infections because of their low bioavailability. In the present study, we developed an AMP derived from Romo1 (AMPR-11) that exhibits a broad spectrum of antimicrobial activity. AMPR-11 showed remarkable efficacy against sepsis-causing bacteria, including multidrug-resistant strains, with low toxicity in a murine model of sepsis after intravenous administration. It seems that AMPR-11 disrupts bacterial membranes by interacting with cardiolipin and lipid A. From the results of this study, we suggest that AMPR-11 is a new class of agent for overcoming low efficacy in the intravenous application of AMPs and is a promising candidate to overcome multidrug resistance.

IMPORTANCE Abuse of antibiotics often leads to increase of multidrug-resistant (MDR) bacteria, which threatens the life of human beings. To overcome threat of antibiotic resistance, scientists are developing a novel class of antibiotics, antimicrobial peptides, that can eradicate MDR bacteria. Unfortunately, these antibiotics have mainly been developed to cure bacterial skin infections rather than others, such as life-threatening sepsis. Major pharmaceutical companies have tried to develop antiseptic drugs; however, they have not been successful. Here, we report that AMPR-11, the antimicrobial peptide (AMP) derived from mitochondrial nonselective channel Romo1, has antimicrobial activity against Gram-positive and Gram-negative bacteria comprising many clinically isolated MDR strains. Moreover, AMPR-11 increased the survival rate in a murine model of sepsis caused by MDR bacteria. We propose that AMPR-11 could be a novel antiseptic drug candidate with a broad antimicrobial spectrum to overcome MDR bacterial infection.




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Conductance Mechanisms of Rapidly Desensitizing Cation Channelrhodopsins from Cryptophyte Algae

ABSTRACT

Channelrhodopsins guide algal phototaxis and are widely used as optogenetic probes for control of membrane potential with light. "Bacteriorhodopsin-like" cation channelrhodopsins (BCCRs) from cryptophytes differ in primary structure from other CCRs, lacking usual residues important for their cation conductance. Instead, the sequences of BCCR match more closely those of rhodopsin proton pumps, containing residues responsible for critical proton transfer reactions. We report 19 new BCCRs which, together with the earlier 6 known members of this family, form three branches (subfamilies) of a phylogenetic tree. Here, we show that the conductance mechanisms in two subfamilies differ with respect to involvement of the homolog of the proton donor in rhodopsin pumps. Two BCCRs from the genus Rhodomonas generate photocurrents that rapidly desensitize under continuous illumination. Using a combination of patch clamp electrophysiology, absorption, Raman spectroscopy, and flash photolysis, we found that the desensitization is due to rapid accumulation of a long-lived nonconducting intermediate of the photocycle with unusually blue-shifted absorption with a maximum at 330 nm. These observations reveal diversity within the BCCR family and contribute to deeper understanding of their independently evolved cation channel function.

IMPORTANCE Cation channelrhodopsins, light-gated channels from flagellate green algae, are extensively used as optogenetic photoactivators of neurons in research and recently have progressed to clinical trials for vision restoration. However, the molecular mechanisms of their photoactivation remain poorly understood. We recently identified cryptophyte cation channelrhodopsins, structurally different from those of green algae, which have separately evolved to converge on light-gated cation conductance. This study reveals diversity within this new protein family and describes a subclade with unusually rapid desensitization that results in short transient photocurrents in continuous light. Such transient currents have not been observed in the green algae channelrhodopsins and are potentially useful in optogenetic protocols. Kinetic UV-visible (UV-vis) spectroscopy and photoelectrophysiology reveal that the desensitization is caused by rapid accumulation of a nonconductive photointermediate in the photochemical reaction cycle. The absorption maximum of the intermediate is 330 nm, the shortest wavelength reported in any rhodopsin, indicating a novel chromophore structure.




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Polygenic risk scores of several subtypes of epilepsies in a founder population

Objective

Polygenic risk scores (PRSs) are used to quantify the cumulative effects of a number of genetic variants, which may individually have a very small effect on susceptibility to a disease; we used PRSs to better understand the genetic contribution to common epilepsy and its subtypes.

Methods

We first replicated previous single associations using 373 unrelated patients. We then calculated PRSs in the same French Canadian patients with epilepsy divided into 7 epilepsy subtypes and population-based controls. We fitted a logistic mixed model to calculate the variance explained by the PRS using pseudo-R2 statistics.

Results

We show that the PRS explains more of the variance in idiopathic generalized epilepsy than in patients with nonacquired focal epilepsy. We also demonstrate that the variance explained is different within each epilepsy subtype.

Conclusions

Globally, we support the notion that PRSs provide a reliable measure to rightfully estimate the contribution of genetic factors to the pathophysiologic mechanism of epilepsies, but further studies are needed on PRSs before they can be used clinically.




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The Circadian Clock Influences the Long-Term Water Use Efficiency of Arabidopsis

In plants, water use efficiency (WUE) is a complex trait arising from numerous physiological and developmental characteristics. Here, we investigated the involvement of circadian regulation in long-term WUE in Arabidopsis (Arabidopsis thaliana) under light and dark conditions. Circadian rhythms are generated by the circadian oscillator, which provides a cellular measure of the time of day. In plants, the circadian oscillator contributes to the regulation of many aspects of physiology, including stomatal opening, rate of photosynthesis, carbohydrate metabolism, and developmental processes such as the initiation of flowering. We investigated the impact of the misregulation of numerous genes encoding various components of the circadian oscillator on whole plant, long-term WUE. From this analysis, we identified a role for the circadian oscillator in WUE. It appears that the circadian clock contributes to the control of transpiration and biomass accumulation. We also established that the circadian oscillator within guard cells can contribute to long-term WUE. Our experiments indicate that knowledge of circadian regulation will be important for developing crops with improved WUE.




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Arabidopsis DNA Replication Initiates in Intergenic, AT-Rich Open Chromatin

The selection and firing of DNA replication origins play key roles in ensuring that eukaryotes accurately replicate their genomes. This process is not well documented in plants due in large measure to difficulties in working with plant systems. We developed a new functional assay to label and map very early replicating loci that must, by definition, include at least a subset of replication origins. Arabidopsis (Arabidopsis thaliana) cells were briefly labeled with 5-ethynyl-2'-deoxy-uridine, and nuclei were subjected to two-parameter flow sorting. We identified more than 5500 loci as initiation regions (IRs), the first regions to replicate in very early S phase. These were classified as strong or weak IRs based on the strength of their replication signals. Strong initiation regions were evenly spaced along chromosomal arms and depleted in centromeres, while weak initiation regions were enriched in centromeric regions. IRs are AT-rich sequences flanked by more GC-rich regions and located predominantly in intergenic regions. Nuclease sensitivity assays indicated that IRs are associated with accessible chromatin. Based on these observations, initiation of plant DNA replication shows some similarity to, but is also distinct from, initiation in other well-studied eukaryotic systems.




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Phosphomimetic T335D Mutation of Hydroxypyruvate Reductase 1 Modifies Cofactor Specificity and Impacts Arabidopsis Growth in Air

Photorespiration is an essential process in oxygenic photosynthetic organisms triggered by the oxygenase activity of Rubisco. In peroxisomes, photorespiratory HYDROXYPYRUVATE REDUCTASE1 (HPR1) catalyzes the conversion of hydroxypyruvate to glycerate together with the oxidation of a pyridine nucleotide cofactor. HPR1 regulation remains poorly understood; however, HPR1 phosphorylation at T335 has been reported. By comparing the kinetic properties of phosphomimetic (T335D), nonphosphorylatable (T335A), and wild-type recombinant Arabidopsis (Arabidopsis thaliana) HPR1, it was found that HPR1-T335D exhibits reduced NADH-dependent hydroxypyruvate reductase activity while showing improved NADPH-dependent activity. Complementation of the Arabidopsis hpr1-1 mutant by either wild-type HPR1 or HPR1-T335A fully complemented the photorespiratory growth phenotype of hpr1-1 in ambient air, whereas HPR1-T335D-containing hpr1-1 plants remained smaller and had lower photosynthetic CO2 assimilation rates. Metabolite analyses indicated that these phenotypes were associated with subtle perturbations in the photorespiratory cycle of HPR1-T335D-complemented hpr1-1 rosettes compared to all other HPR1-containing lines. Therefore, T335 phosphorylation may play a role in the regulation of HPR1 activity in planta, although it was not required for growth under ambient air controlled conditions. Furthermore, improved NADP-dependent HPR1 activities in peroxisomes could not compensate for the reduced NADH-dependent HPR1 activity.




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The Four Arabidopsis Choline/Ethanolamine Kinase Isozymes Play Distinct Roles in Metabolism and Development

Phosphatidylcholine and phosphatidylethanolamine are two major phospholipid classes in eukaryotes. Each biosynthesis pathway starts with the phosphorylation of choline (Cho) or ethanolamine (Etn) catalyzed by either choline or ethanolamine kinase (CEK). Arabidopsis contains four CEK isoforms, but their isozyme-specific roles in metabolism and development are poorly described. Here, we showed that these four CEKs have distinct substrate specificities in vitro. While CEK1 and CEK2 showed substrate preference for Cho over Etn, CEK3 and CEK4 had clear substrate specificity for Cho and Etn, respectively. In vivo, CEK1, CEK2, and CEK3 exhibited kinase activity for Cho but not Etn, although the latter two isoforms showed rather minor contributions to total Cho kinase activity in both shoots and roots. The knockout mutants of CEK2 and CEK3 both affected root growth, and these isoforms had nonoverlapping cell-type-specific expression patterns in the root meristematic zone. In-depth phenotype analysis, as well as chemical and genetic complementation, revealed that CEK3, a Cho-specific kinase, is involved in cell elongation during root development. Phylogenetic analysis of CEK orthologs in Brassicaceae species showed evolutionary divergence between Etn kinases and Cho kinases. Collectively, our results demonstrate the distinct roles of the four CEK isoforms in Cho/Etn metabolism and plant development.




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Specific Lhc Proteins Are Bound to PSI or PSII Supercomplexes in the Diatom Thalassiosira pseudonana

Despite the ecological relevance of diatoms, many aspects of their photosynthetic machinery remain poorly understood. Diatoms differ from the green lineage of oxygenic organisms by their photosynthetic pigments and light-harvesting complex (Lhc) proteins, the latter of which are also called fucoxanthin-chlorophyll proteins (FCP). These are composed of three groups of proteins: Lhcf as the main group, Lhcr that are PSI associated, and Lhcx that are involved in photoprotection. The FCP complexes are assembled in trimers and higher oligomers. Several studies have investigated the biochemical properties of purified FCP complexes, but limited knowledge is available about their interaction with the photosystem cores. In this study, isolation of stable supercomplexes from the centric diatom Thalassiosira pseudonana was achieved. To preserve in vivo structure, the separation of thylakoid complexes was performed by native PAGE and sucrose density centrifugation. Different subpopulations of PSI and PSII supercomplexes were isolated and their subunits identified. Analysis of Lhc antenna composition identified Lhc(s) specific for either PSI (Lhcr 1, 3, 4, 7, 10–14, and Lhcf10) or PSII (Lhcf 1–7, 11, and Lhcr2). Lhcx6_1 was reproducibly found in PSII supercomplexes, whereas its association with PSI was unclear. No evidence was found for the interaction between photosystems and higher oligomeric FCPs, comprising Lhcf8 as the main component. Although the subunit composition of the PSII supercomplexes in comparison with that of the trimeric FCP complexes indicated a close mutual association, the higher oligomeric pool is only weakly associated with the photosystems, albeit its abundance in the thylakoid membrane.




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AT the Onset of DNA Replication in Arabidopsis




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EPSIN1 Contributes to Plant Immunity by Modulating the Abundance of Pattern Recognition Receptors at the Plasma Membrane




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Surviving Sepsis Campaign International Guidelines




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Pathogen Genetic Control of Transcriptome Variation in the Arabidopsis thaliana - Botrytis cinerea Pathosystem [Genetics of Complex Traits]

In plant–pathogen relations, disease symptoms arise from the interaction of the host and pathogen genomes. Host–pathogen functional gene interactions are well described, whereas little is known about how the pathogen genetic variation modulates both organisms’ transcriptomes. To model and generate hypotheses on a generalist pathogen control of gene expression regulation, we used the Arabidopsis thalianaBotrytis cinerea pathosystem and the genetic diversity of a collection of 96 B. cinerea isolates. We performed expression-based genome-wide association (eGWA) for each of 23,947 measurable transcripts in Arabidopsis (host), and 9267 measurable transcripts in B. cinerea (pathogen). Unlike other eGWA studies, we detected a relative absence of locally acting expression quantitative trait loci (cis-eQTL), partly caused by structural variants and allelic heterogeneity hindering their identification. This study identified several distantly acting trans-eQTL linked to eQTL hotspots dispersed across Botrytis genome that altered only Botrytis transcripts, only Arabidopsis transcripts, or transcripts from both species. Gene membership in the trans-eQTL hotspots suggests links between gene expression regulation and both known and novel virulence mechanisms in this pathosystem. Genes annotated to these hotspots provide potential targets for blocking manipulation of the host response by this ubiquitous generalist necrotrophic pathogen.




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Complexes between C-Reactive Protein and Very Low Density Lipoprotein Delay Bacterial Clearance in Sepsis [INFECTIOUS DISEASE AND HOST RESPONSE]

Key Points

  • Kupffer cells phagocytose both bacteria and CRP–VLDL complexes.

  • High levels of CRP–VLDL complexes delay bacterial clearance.

  • Pch disrupts CRP–VLDL complexes to improve bacterial clearance.




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    A New Gorilla Adenoviral Vector with Natural Lung Tropism Avoids Liver Toxicity and Is Amenable to Capsid Engineering and Vector Retargeting [Gene Delivery]

    Human adenoviruses have many attractive features for gene therapy applications. However, the high prevalence of preexisting immunity against these viruses in general populations worldwide has greatly limited their clinical utility. In addition, the most commonly used human adenovirus, human adenovirus subgroup C serotype 5 (HAd5), when systemically administered, triggers systemic inflammation and toxicity, with the liver being the most severely affected organ. Here, we evaluated the utility and safety of a new low-seroprevalence gorilla adenovirus (GAd; GC46) as a gene transfer vector in mice. Biodistribution studies revealed that systemically administered GAd had a selective and robust lung endothelial cell (EC) tropism with minimal vector expression throughout many other organs and tissues. Administration of a high dose of GAd accomplished extensive transgene expression in the lung yet elicited no detectable inflammatory histopathology in this organ. Furthermore, GAd, unlike HAd5, did not exhibit hepatotropism or induce liver inflammatory toxicity in mice, demonstrating the exceptional safety profile of the vector vis-à-vis systemic utility. We further demonstrated that the GAd capsid fiber shared the flexibility of the HAd5 equivalent for permitting genetic modification; GAd with the pan-EC-targeting ligand myeloid cell-binding peptide (MBP) incorporated in the capsid displayed a reduced lung tropism and efficiently retargeted gene expression to vascular beds in other organs.

    IMPORTANCE In the aggregate, our mouse studies suggest that GAd is a promising gene therapy vector that utilizes lung ECs as a source of therapeutic payload production and a highly desirable toxicity profile. Further genetic engineering of the GAd capsid holds the promise of in vivo vector tropism modification and targeting.




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    Glycoprotein 5 Is Cleaved by Cathepsin E during Porcine Reproductive and Respiratory Syndrome Virus Membrane Fusion [Virus-Cell Interactions]

    Porcine reproductive and respiratory syndrome (PRRS) is a serious viral disease affecting the global swine industry. Its causative agent, PRRS virus (PRRSV), is an enveloped virus, and therefore membrane fusion between its envelope and host cell target membrane is critical for viral infection. Though much research has focused on PRRSV infection, the detailed mechanisms involved in its membrane fusion remain to be elucidated. In the present study, we performed confocal microscopy in combination with a constitutively active (CA) or dominant negative (DN) mutant, specific inhibitors, and small interfering RNAs (siRNAs), as well as multiple other approaches, to explore PRRSV membrane fusion. We first observed that PRRSV membrane fusion occurred in Rab11-recycling endosomes during early infection using labeled virions and subcellular markers. We further demonstrated that low pH and cathepsin E in Rab11-recycling endosomes are critical for PRRSV membrane fusion. Moreover, PRRSV glycoprotein 5 (GP5) is identified as being cleaved by cathepsin E during this process. Taken together, our findings provide in-depth information regarding PRRSV pathogenesis, which support a novel basis for the development of antiviral drugs and vaccines.

    IMPORTANCE PRRS, caused by PRRSV, is an economically critical factor in pig farming worldwide. As PRRSV is a lipid membrane-wrapped virus, merging of the PRRSV envelope with the host cell membrane is indispensable for viral infection. However, there is a lack of knowledge on its membrane fusion. Here, we first explored when and where PRRSV membrane fusion occurs. Furthermore, we determined which host cell factors were involved in the process. Importantly, PRRSV GP5 is shown to be cleaved by cathepsin E during membrane fusion. Our work not only provides information on PRRSV membrane fusion for the first time but also deepens our understanding of the molecular mechanisms of PRRSV infection, which provides a foundation for future applications in the prevention and control of PRRS.




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    Seasonal timing adaptation across the geographic range of Arabidopsis thaliana [Evolution]

    The most fundamental genetic program of an annual plant defines when to grow and reproduce and when to remain dormant in the soil as a seed. With the right timing, plants can even live in hostile regions with only a few months of growth-favorable abundant rains and mild temperatures. To...




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    An arrestin-1 surface opposite of its interface with photoactivated rhodopsin engages with enolase-1 [Protein Structure and Folding]

    Arrestin-1 is the arrestin family member responsible for inactivation of the G protein–coupled receptor rhodopsin in photoreceptors. Arrestin-1 is also well-known to interact with additional protein partners and to affect other signaling cascades beyond phototransduction. In this study, we investigated one of these alternative arrestin-1 binding partners, the glycolysis enzyme enolase-1, to map the molecular contact sites between these two proteins and investigate how the binding of arrestin-1 affects the catalytic activity of enolase-1. Using fluorescence quench protection of strategically placed fluorophores on the arrestin-1 surface, we observed that arrestin-1 primarily engages enolase-1 along a surface that is opposite of the side of arrestin-1 that binds photoactivated rhodopsin. Using this information, we developed a molecular model of the arrestin-1–enolase-1 complex, which was validated by targeted substitutions of charge-pair interactions. Finally, we identified the likely source of arrestin's modulation of enolase-1 catalysis, showing that selective substitution of two amino acids in arrestin-1 can completely remove its effect on enolase-1 activity while still remaining bound to enolase-1. These findings open up opportunities for examining the functional effects of arrestin-1 on enolase-1 activity in photoreceptors and their surrounding cells.




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    Pro-515 of the dynamin-like GTPase MxB contributes to HIV-1 inhibition by regulating MxB oligomerization and binding to HIV-1 capsid [Microbiology]

    Interferon-regulated myxovirus resistance protein B (MxB) is an interferon-induced GTPase belonging to the dynamin superfamily. It inhibits infection with a wide range of different viruses, including HIV-1, by impairing viral DNA entry into the nucleus. Unlike the related antiviral GTPase MxA, MxB possesses an N-terminal region that contains a nuclear localization signal and is crucial for inhibiting HIV-1. Because MxB previously has been shown to reside in both the nuclear envelope and the cytoplasm, here we used bioinformatics and biochemical approaches to identify a nuclear export signal (NES) responsible for MxB's cytoplasmic location. Using the online computational tool LocNES (Locating Nuclear Export Signals or NESs), we identified five putative NES candidates in MxB and investigated whether their deletion caused nuclear localization of MxB. Our results revealed that none of the five deletion variants relocates to the nucleus, suggesting that these five predicted NES sequences do not confer NES activity. Interestingly, deletion of one sequence, encompassing amino acids 505–527, abrogated the anti-HIV-1 activity of MxB. Further mutation experiments disclosed that amino acids 515–519, and Pro-515 in particular, regulate MxB oligomerization and its binding to HIV-1 capsid, thereby playing an important role in MxB-mediated restriction of HIV-1 infection. In summary, our results indicate that none of the five predicted NES sequences in MxB appears to be required for its nuclear export. Our findings also reveal several residues in MxB, including Pro-515, critical for its oligomerization and anti-HIV-1 function.




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    Is APOE {varepsilon}4 associated with cognitive performance in early MS?

    Objective

    To assess the impact of APOE polymorphisms on cognitive performance in patients newly diagnosed with clinically isolated syndrome (CIS) or relapsing-remitting MS (RRMS).

    Methods

    This multicenter cohort study included 552 untreated patients recently diagnosed with CIS or RRMS according to the 2005 revised McDonald criteria. The single nucleotide polymorphisms rs429358 (4) and rs7412 (2) of the APOE haplotype were assessed by allelic discrimination assays. Cognitive performance was evaluated using the 3-second paced auditory serial addition test and the Multiple Sclerosis Inventory Cognition (MUSIC). Sum scores were calculated to approximate the overall cognitive performance and memory-centered cognitive functions. The impact of the APOE carrier status on cognitive performance was assessed using multiple linear regression models, also including demographic, clinical, MRI, and lifestyle factors.

    Results

    APOE 4 homozygosity was associated with lower overall cognitive performance, whereas no relevant association was observed for APOE 4 heterozygosity or APOE 2 carrier status. Furthermore, higher disability levels, MRI lesion load, and depressive symptoms were associated with lower cognitive performance. Patients consuming alcohol had higher test scores than patients not consuming alcohol. Female sex, lower disability, and alcohol consumption were associated with better performance in the memory-centered subtests of MUSIC, whereas no relevant association was observed for APOE carrier status.

    Conclusion

    Along with parameters of a higher disease burden, APOE 4 homozygosity was identified as a potential predictor of cognitive performance in this large cohort of patients with CIS and early RRMS.




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    Effect of depositional water content on the collapsibility of a reconstituted loess

    Loess, a wind-blown silty soil, can be deposited under a variety of moisture conditions, including dry deposition, wet deposition and gravitational settling of aggregations formed in moist air by capillary forces at grain contacts. This experimental study uses single and double oedometer tests to assess the effect of depositional water content on the collapse potential of reconstituted samples of the Langley Silt Member, known as Brickearth, a natural loessic soil. A freefall sample preparation technique was used to mimic loess formation and environmental scanning electron microscopy was used to relate the observed behaviour to sample fabric. The results show that loess deposited at higher water contents has a greater collapse potential, which is shown to be related to its looser, more granular fabric.




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    Arabidopsis retrotransposon virus-like particles and their regulation by epigenetically activated small RNA [RESEARCH]

    In Arabidopsis, LTR retrotransposons are activated by mutations in the chromatin gene DECREASE in DNA METHYLATION 1 (DDM1), giving rise to 21- to 22-nt epigenetically activated siRNA (easiRNA) that depend on RNA DEPENDENT RNA POLYMERASE 6 (RDR6). We purified virus-like particles (VLPs) from ddm1 and ddm1rdr6 mutants in which genomic RNA is reverse transcribed into complementary DNA. High-throughput short-read and long-read sequencing of VLP DNA (VLP DNA-seq) revealed a comprehensive catalog of active LTR retrotransposons without the need for mapping transposition, as well as independent of genomic copy number. Linear replication intermediates of the functionally intact COPIA element EVADE revealed multiple central polypurine tracts (cPPTs), a feature shared with HIV in which cPPTs promote nuclear localization. For one member of the ATCOPIA52 subfamily (SISYPHUS), cPPT intermediates were not observed, but abundant circular DNA indicated transposon "suicide" by auto-integration within the VLP. easiRNA targeted EVADE genomic RNA, polysome association of GYPSY (ATHILA) subgenomic RNA, and transcription via histone H3 lysine-9 dimethylation. VLP DNA-seq provides a comprehensive landscape of LTR retrotransposons and their control at transcriptional, post-transcriptional, and reverse transcriptional levels.




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    The Transcriptional Aftermath in Two Independently Formed Hybrids of the Opportunistic Pathogen Candida orthopsilosis

    ABSTRACT

    Interspecific hybridization can drive evolutionary adaptation to novel environments. The Saccharomycotina clade of budding yeasts includes many hybrid lineages, and hybridization has been proposed as a source for new pathogenic species. Candida orthopsilosis is an emerging opportunistic pathogen for which most clinical isolates are hybrids, each derived from one of at least four independent crosses between the same two parental lineages. To gain insight into the transcriptomic aftermath of hybridization in these pathogens, we analyzed allele-specific gene expression in two independently formed hybrid strains and in a homozygous strain representative of one parental lineage. Our results show that the effect of hybridization on overall gene expression is rather limited, affecting ~4% of the genes studied. However, we identified a larger effect in terms of imbalanced allelic expression, affecting ~9.5% of the heterozygous genes in the hybrids. This effect was larger in the hybrid with more extensive loss of heterozygosity, which may indicate a tendency to avoid loss of heterozygosity in these genes. Consistently, the number of shared genes with allele-specific expression in the two independently formed hybrids was higher than random expectation, suggesting selective retention. Some of the imbalanced genes have functions related to pathogenicity, including zinc transport and superoxide dismutase activities. While it remains unclear whether the observed imbalanced genes play a role in virulence, our results suggest that differences in allele-specific expression may add an additional layer of phenotypic plasticity to traits related to virulence in C. orthopsilosis hybrids.

    IMPORTANCE How new pathogens emerge is an important question that remains largely unanswered. Some emerging yeast pathogens are hybrids originated through the crossing of two different species, but how hybridization contributes to higher virulence is unclear. Here, we show that hybrids selectively retain gene regulation plasticity inherited from the two parents and that this plasticity affects genes involved in virulence.




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    Case 3: Polyuria and Polydipsia in an 11-year-old Boy




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    Risk of Ipsilateral Reamputation Following an Incident Toe Amputation Among U.S. Military Veterans With Diabetes, 2005-2016

    OBJECTIVE

    To assess whether the risk of subsequent lower-limb amputations and death following an initial toe amputation among individuals with diabetes has changed over time and varies by demographic characteristics and geographic region.

    RESEARCH DESIGN AND METHODS

    Using Veterans Health Administration (VHA) electronic medical records from 1 October 2004 to 30 September 2016, we determined risk of subsequent ipsilateral minor and major amputation within 1 year after an initial toe/ray amputation among veterans with diabetes. To assess changes in the annual rate of subsequent amputation over time, we estimated age-adjusted incidence of minor and major subsequent ipsilateral amputation for each year, separately for African Americans (AAs) and whites. Geographic variation was assessed across VHA markets (n = 89) using log-linear Poisson regression models adjusting for age and ethnoracial category.

    RESULTS

    Among 17,786 individuals who had an initial toe amputation, 34% had another amputation on the same limb within 1 year, including 10% who had a major ipsilateral amputation. Median time to subsequent ipsilateral amputation (minor or major) was 36 days. One-year risk of subsequent major amputation decreased over time, but risk of subsequent minor amputation did not. Risk of subsequent major ipsilateral amputation was higher in AAs than whites. After adjusting for age and ethnoracial category, 1-year risk of major subsequent amputation varied fivefold across VHA markets.

    CONCLUSIONS

    Nearly one-third of individuals require reamputation following an initial toe amputation, although risks of subsequent major ipsilateral amputation have decreased over time. Nevertheless, risks remain particularly high for AAs and vary substantially geographically.




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    The contact system proteases play disparate roles in streptococcal sepsis

    Sepsis causes an activation of the human contact system, an inflammatory response mechanism against foreign surfaces, proteins and pathogens. The serine proteases of the contact system, factor XII and plasma kallikrein, are decreased in plasma of septic patients, which was previously associated with an unfavorable outcome. However, the precise mechanisms and roles of contact system factors in bacterial sepsis are poorly understood. We, therefore, studied the physiological relevance of factor XII and plasma kallikrein in a mouse model of experimental sepsis. We show that decreased plasma kallikrein concentration in septic mice is a result of reduced mRNA expression plasma prekallikrein gene, indicating that plasma kallikrein belong to negative acute phase proteins. Investigations regarding the pathophysiological function of contact system proteases during sepsis revealed different roles for factor XII and plasma kallikrein. In vitro, factor XII decelerated bacteria induced fibrinolysis, whereas plasma kallikrein supported it. Remarkably, depletion of plasma kallikrein (but not factor XII) by treatment with antisense-oligonucleotides, dampens bacterial dissemination and growth in multiple organs in the mouse sepsis model. These findings identify plasma kallikrein as a novel host pathogenicity factor in Streptococcus pyogenes sepsis.




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    In Situ Immune Profiling of Heart Transplant Biopsies Improves Diagnostic Accuracy and Rejection Risk Stratification

    Recognizing that guideline-directed histologic grading of endomyocardial biopsy tissue samples for rejection surveillance has limited diagnostic accuracy, quantitative, in situ characterization was performed of several important immune cell types in a retrospective cohort of clinical endomyocardial tissue samples. Differences between cases were identified and were grouped by histologic grade versus clinical rejection trajectory, with significantly increased programmed death ligand 1+, forkhead box P3+, and cluster of differentiation 68+ cells suppressed in clinically evident rejections, especially cases with marked clinical-histologic discordance. Programmed death ligand 1+, forkhead box P3+, and cluster of differentiation 68+ cell proportions are also significantly higher in "never-rejection" when compared with "future-rejection." These findings suggest that in situ immune modulators regulate the severity of cardiac allograft rejection.