polymer

POLYMERIZABLE LIQUID CRYSTAL COMPOUND, COMPOSITION FOR OPTICAL FILM, AND OPTICAL FILM, COMPENSATION FILM, ANTIREFLECTIVE FILM, AND DISPLAY DEVICE INCLUDING THE SAME

A polymerizable liquid crystal compound represented by Chemical Formula 1: wherein in Chemical Formula 1, groups and variables are the same as defined in the detailed description.




polymer

CONDUCTING POLYMERS FOR DIRECT SENSING OF METAL IONS

The present invention provides an ion selective electrode comprising an electrode having a coating deposited on the electrode, wherein the coating comprises one or more aroyl-thiourea ionophores incorporated into a polymer matrix to selectively interact with one or more ions. The aroylthiourea ionophores may be poly-5, poly-6, poly-7, poly-7a, poly-7b, poly-8a, poly-8b or a combination thereof, e.g., a bis(furoylthiourea)benzene derivative, a 2,2'-bith-iophenyl derivative that selectively senses Pb2+ ions. The polymer matrix may be a polyaniline, a polythiophene or the polymer matrix may be an aroylthiourea ionophore inserted into polyvinyl-chloride for Pb2+ and Hg2+ ion sensing.




polymer

USE OF FLUORESCENT POLYMERS IN MARKING COMPOSITIONS FOR THE DIAGNOSTIC DETERMINATION OF CLEANING PERFORMANCE

The present invention generally relates to fluorescent marking compositions and their use to determine whether a surface has been cleaned. More particularly, the marking compositions comprise fluorescent polymers.




polymer

METHOD FOR REMOVING GLYPHOSATE FROM A SOLUTION USING FUNCTIONALIZED POLYMERIC NANOPARTICLES

A method for removing glyphosate from a solution by contacting the solution with a polymeric particle including a moiety selected from the group consisting of ammonium, amine and combinations thereof, wherein the moiety is positively charged in the solution.




polymer

MONOFUNCTIONAL AMINES AS ADHESION PRIMERS FOR CONDUCTIVE POLYMERS

The present invention relates to a process for producing an electrolytic capacitor, the process comprising process steps i) ii): i) providing a capacitor body (1) that comprises an electrode body (2) of an electrode material,a dielectric (3) which at least partially covers the surface of this electrode material, anda solid electrolyte (4) at least comprising an electrically conductive material which at least partially covers the dielectric surface; ii) applying a primer solution e) to the capacitor body (1), followed by an application of a solution or dispersion a) comprising a conjugated polymer b) and a solvent or dispersant d), followed by an at least partial removal of the solvent or dispersant d) for the formation of the polymeric outer layer (5) that is formed onto the capacitor body (1); wherein the primer solution e) comprises at least one monofunctional amine and at least one carboxylic acid.




polymer

POLYMER, ORGANIC LIGHT-EMITTING DEVICE MATERIAL INCLUDING THE SAME, AND ORGANIC LIGHT-EMITTING DEVICE INCLUDING THE ORGANIC LIGHT-EMITTING DEVICE MATERIAL

A polymer comprising a first repeating unit represented by Formula 1: wherein, in Formula 1, groups and variables are the same as described in the specification.




polymer

POLYMER COMPOUND AND ORGANIC SEMICONDUCTOR DEVICE USING THE SAME

A polymer compound comprising a structural unit represented by the formula (1): wherein R1, R2, R3 and R4 each independently represent an alkyl group, an aryl group or a monovalent heterocyclic group, and these groups optionally have a substituent, two rings A may be the same or different, and represent a thiophene ring, a benzothiophene ring or a thienothiophene ring, n represents 1 or 2, and X represents a halogen atom, an alkyl group, an alkoxy group, an alkylthio group, an amino group, an aryl group, a monovalent heterocyclic group, an alkenyl group or an alkynyl group, and these groups optionally have a substituent, and when n is 2, two groups X may be the same or different.




polymer

Audi is increasingly using polymer 3D printing in automotive production

German automobile manufacturer Audi AG is expanding the use of 3D printers in production. Custom-designed and locally printed auxiliary tools from the 3D printer help employees on the production lines.



  • 3D Printing Applications

polymer

ClearValue, Inc. v. Pearl River Polymers, Inc.

(United States Federal Circuit) - In a suit involving claims of indirect patent infringement and misappropriation of a trade secret: 1) the district court's denial of the defendant's motions for judgment as a matter of law of invalidity and noninfringement is reversed, where the jury lacked substantial evidence to find that another patent did not anticipate the claim; and 2) the district court's grant of judgment as a matter of law to the defendant on the plaintiff's trade secret claim is affirmed, where another patent publicly disclosed the alleged secret before the plaintiff communicated it to the defendant, and thus the jury's verdict of trade secret misappropriation was not supported by substantial evidence.




polymer

Polymers and People — Summer German Internship

MSE Junior Katie Daehn talks about her summer research internship in Germany. Having lived in Columbus my whole life, living in Germany for 12 weeks with a DAAD RISE scholarship was a hugechance for growth, both technically and personally. I left everything that was comfortable and familiar and headed on my own to Jena, Germany […]




polymer

Three distinct glycosylation pathways are involved in the decoration of Lactococcus lactis cell wall glycopolymers [Microbiology]

Extracytoplasmic sugar decoration of glycopolymer components of the bacterial cell wall contributes to their structural diversity. Typically, the molecular mechanism that underpins such a decoration process involves a three-component glycosylation system (TGS) represented by an undecaprenyl-phosphate (Und-P) sugar-activating glycosyltransferase (Und-P GT), a flippase, and a polytopic glycosyltransferase (PolM GT) dedicated to attaching sugar residues to a specific glycopolymer. Here, using bioinformatic analyses, CRISPR-assisted recombineering, structural analysis of cell wall–associated polysaccharides (CWPS) through MALDI-TOF MS and methylation analysis, we report on three such systems in the bacterium Lactococcus lactis. On the basis of sequence similarities, we first identified three gene pairs, csdAB, csdCD, and csdEF, each encoding an Und-P GT and a PolM GT, as potential TGS component candidates. Our experimental results show that csdAB and csdCD are involved in Glc side-chain addition on the CWPS components rhamnan and polysaccharide pellicle (PSP), respectively, whereas csdEF plays a role in galactosylation of lipoteichoic acid (LTA). We also identified a potential flippase encoded in the L. lactis genome (llnz_02975, cflA) and confirmed that it participates in the glycosylation of the three cell wall glycopolymers rhamnan, PSP, and LTA, thus indicating that its function is shared by the three TGSs. Finally, we observed that glucosylation of both rhamnan and PSP can increase resistance to bacteriophage predation and that LTA galactosylation alters L. lactis resistance to bacteriocin.




polymer

The streptococcal multidomain fibrillar adhesin CshA has an elongated polymeric architecture [Microbiology]

The cell surfaces of many bacteria carry filamentous polypeptides termed adhesins that enable binding to both biotic and abiotic surfaces. Surface adherence is facilitated by the exquisite selectivity of the adhesins for their cognate ligands or receptors and is a key step in niche or host colonization and pathogenicity. Streptococcus gordonii is a primary colonizer of the human oral cavity and an opportunistic pathogen, as well as a leading cause of infective endocarditis in humans. The fibrillar adhesin CshA is an important determinant of S. gordonii adherence, forming peritrichous fibrils on its surface that bind host cells and other microorganisms. CshA possesses a distinctive multidomain architecture comprising an N-terminal target-binding region fused to 17 repeat domains (RDs) that are each ∼100 amino acids long. Here, using structural and biophysical methods, we demonstrate that the intact CshA repeat region (CshA_RD1–17, domains 1–17) forms an extended polymeric monomer in solution. We recombinantly produced a subset of CshA RDs and found that they differ in stability and unfolding behavior. The NMR structure of CshA_RD13 revealed a hitherto unreported all β-fold, flanked by disordered interdomain linkers. These findings, in tandem with complementary hydrodynamic studies of CshA_RD1–17, indicate that this polypeptide possesses a highly unusual dynamic transitory structure characterized by alternating regions of order and disorder. This architecture provides flexibility for the adhesive tip of the CshA fibril to maintain bacterial attachment that withstands shear forces within the human host. It may also help mitigate deleterious folding events between neighboring RDs that share significant structural identity without compromising mechanical stability.




polymer

In Vivo Identification of Human Small Ubiquitin-like Modifier Polymerization Sites by High Accuracy Mass Spectrometry and an in Vitro to in Vivo Strategy

Ivan Matic
Jan 1, 2008; 7:132-144
Research




polymer

Topology and Geometry of Biopolymers

Erica Flapan and Helen Wong, editors. American Mathematical Society, 2020, CONM, volume 746, approx. 248 pp. ISBN: 978-1-4704-4840-0 (print), 978-1-4704-5456-2 (online).

This book contains the proceedings of the AMS Special Session on Topology of Biopolymers, held from April 21–22, 2018, at Northeastern...




polymer

Research found a new way to make functional materials based on polymers of metal clusters

(University of Jyväskylä - Jyväskylän yliopisto) Researchers at the universities of Jyvaskyla and Xiamen discovered a novel way to make functional macroscopic crystalline materials out of nanometer-size 34-atom silver-gold intermetallic clusters. The cluster material has a highly anisotropic electrical conductivity, being a semiconductor in one direction and an electrical insulator in other directions. The research was published in Nature Communications on May 6, 2020.




polymer

Three distinct glycosylation pathways are involved in the decoration of Lactococcus lactis cell wall glycopolymers [Microbiology]

Extracytoplasmic sugar decoration of glycopolymer components of the bacterial cell wall contributes to their structural diversity. Typically, the molecular mechanism that underpins such a decoration process involves a three-component glycosylation system (TGS) represented by an undecaprenyl-phosphate (Und-P) sugar-activating glycosyltransferase (Und-P GT), a flippase, and a polytopic glycosyltransferase (PolM GT) dedicated to attaching sugar residues to a specific glycopolymer. Here, using bioinformatic analyses, CRISPR-assisted recombineering, structural analysis of cell wall–associated polysaccharides (CWPS) through MALDI-TOF MS and methylation analysis, we report on three such systems in the bacterium Lactococcus lactis. On the basis of sequence similarities, we first identified three gene pairs, csdAB, csdCD, and csdEF, each encoding an Und-P GT and a PolM GT, as potential TGS component candidates. Our experimental results show that csdAB and csdCD are involved in Glc side-chain addition on the CWPS components rhamnan and polysaccharide pellicle (PSP), respectively, whereas csdEF plays a role in galactosylation of lipoteichoic acid (LTA). We also identified a potential flippase encoded in the L. lactis genome (llnz_02975, cflA) and confirmed that it participates in the glycosylation of the three cell wall glycopolymers rhamnan, PSP, and LTA, thus indicating that its function is shared by the three TGSs. Finally, we observed that glucosylation of both rhamnan and PSP can increase resistance to bacteriophage predation and that LTA galactosylation alters L. lactis resistance to bacteriocin.




polymer

Genetic evidence for reconfiguration of DNA polymerase {theta} active site for error-free translesion synthesis in human cells [DNA and Chromosomes]

The action mechanisms revealed by the biochemical and structural analyses of replicative and translesion synthesis (TLS) DNA polymerases (Pols) are retained in their cellular roles. In this regard, DNA polymerase θ differs from other Pols in that whereas purified Polθ misincorporates an A opposite 1,N6-ethenodeoxyadenosine (ϵdA) using an abasic-like mode, Polθ performs predominantly error-free TLS in human cells. To test the hypothesis that Polθ adopts a different mechanism for replicating through ϵdA in human cells than in the purified Pol, here we analyze the effects of mutations in the two highly conserved tyrosine residues, Tyr-2387 and Tyr-2391, in the Polθ active site. Our findings that these residues are indispensable for TLS by the purified Pol but are not required in human cells, as well as other findings, provide strong evidence that the Polθ active site is reconfigured in human cells to stabilize ϵdA in the syn conformation for Hoogsteen base pairing with the correct nucleotide. The evidence that a DNA polymerase can configure its active site entirely differently in human cells than in the purified Pol establishes a new paradigm for DNA polymerase function.




polymer

Fluorescent technique brings aging polymers to light

(American Chemical Society) Modern society relies on polymers, such as polypropylene or polyethylene plastic, for a wide range of applications, from food containers to automobile parts to medical devices. However, like people, polymers age, and when they do, the materials become prone to cracking or breaking. Now, researchers reporting in ACS Central Science have developed a method to visualize variations in polymers that arise with age.




polymer

Fly ash geopolymer concrete: Significantly enhanced resistance to extreme alkali attack

(University of Johannesburg) Fly ash generated by coal-fired power stations is a global environmental headache, creating groundwater and air pollution from vast landfills and ash dams. The waste product can be repurposed into geopolymer concrete, such as precast heat-cured structural elements for buildings. However, a critical durability problem has been low resistance to extreme alkali attack. UJ researchers found that high temperature heat-treatment at 200 degrees Celsius can halve this harmful mechanism in fly ash geopolymer concretes.




polymer

The streptococcal multidomain fibrillar adhesin CshA has an elongated polymeric architecture [Microbiology]

The cell surfaces of many bacteria carry filamentous polypeptides termed adhesins that enable binding to both biotic and abiotic surfaces. Surface adherence is facilitated by the exquisite selectivity of the adhesins for their cognate ligands or receptors and is a key step in niche or host colonization and pathogenicity. Streptococcus gordonii is a primary colonizer of the human oral cavity and an opportunistic pathogen, as well as a leading cause of infective endocarditis in humans. The fibrillar adhesin CshA is an important determinant of S. gordonii adherence, forming peritrichous fibrils on its surface that bind host cells and other microorganisms. CshA possesses a distinctive multidomain architecture comprising an N-terminal target-binding region fused to 17 repeat domains (RDs) that are each ∼100 amino acids long. Here, using structural and biophysical methods, we demonstrate that the intact CshA repeat region (CshA_RD1–17, domains 1–17) forms an extended polymeric monomer in solution. We recombinantly produced a subset of CshA RDs and found that they differ in stability and unfolding behavior. The NMR structure of CshA_RD13 revealed a hitherto unreported all β-fold, flanked by disordered interdomain linkers. These findings, in tandem with complementary hydrodynamic studies of CshA_RD1–17, indicate that this polypeptide possesses a highly unusual dynamic transitory structure characterized by alternating regions of order and disorder. This architecture provides flexibility for the adhesive tip of the CshA fibril to maintain bacterial attachment that withstands shear forces within the human host. It may also help mitigate deleterious folding events between neighboring RDs that share significant structural identity without compromising mechanical stability.




polymer

Genetic evidence for reconfiguration of DNA polymerase {theta} active site for error-free translesion synthesis in human cells [DNA and Chromosomes]

The action mechanisms revealed by the biochemical and structural analyses of replicative and translesion synthesis (TLS) DNA polymerases (Pols) are retained in their cellular roles. In this regard, DNA polymerase θ differs from other Pols in that whereas purified Polθ misincorporates an A opposite 1,N6-ethenodeoxyadenosine (ϵdA) using an abasic-like mode, Polθ performs predominantly error-free TLS in human cells. To test the hypothesis that Polθ adopts a different mechanism for replicating through ϵdA in human cells than in the purified Pol, here we analyze the effects of mutations in the two highly conserved tyrosine residues, Tyr-2387 and Tyr-2391, in the Polθ active site. Our findings that these residues are indispensable for TLS by the purified Pol but are not required in human cells, as well as other findings, provide strong evidence that the Polθ active site is reconfigured in human cells to stabilize ϵdA in the syn conformation for Hoogsteen base pairing with the correct nucleotide. The evidence that a DNA polymerase can configure its active site entirely differently in human cells than in the purified Pol establishes a new paradigm for DNA polymerase function.




polymer

Aquatic biopolymers : understanding their industrial significance and environmental implications

Olatunji, Ololade.
9783030347093 (electronic bk.)




polymer

Busemann functions and semi-infinite O’Connell–Yor polymers

Tom Alberts, Firas Rassoul-Agha, Mackenzie Simper.

Source: Bernoulli, Volume 26, Number 3, 1927--1955.

Abstract:
We prove that given any fixed asymptotic velocity, the finite length O’Connell–Yor polymer has an infinite length limit satisfying the law of large numbers with this velocity. By a Markovian property of the quenched polymer this reduces to showing the existence of Busemann functions : almost sure limits of ratios of random point-to-point partition functions. The key ingredients are the Burke property of the O’Connell–Yor polymer and a comparison lemma for the ratios of partition functions. We also show the existence of infinite length limits in the Brownian last passage percolation model.




polymer

Protesters demand closure of LG Polymers plant in India after deadly gas leak

Villagers placed the bodies of three victims of a deadly gas leak from an LG Polymers plant in southern India at the gates of the site on Saturday and demanded the factory be shut down immediately and its top management arrested.




polymer

Vizag Gas Leak: LG Polymers India Fined Rs 50 Crore By Green Court NGT

The National Green Tribunal slapped an interim penalty of Rs 50 crore on LG Polymers India and sought response from the Centre and others on Friday in the gas leak incident in Visakhapatnam, Andhra...




polymer

All you need to know about LG Polymers plant at the centre of Vizag gas leak

LG Polymer plant uses raw material styrene to make its products, which is highly flammable and releases a poisonous gas when burnt.




polymer

Visakhapatnam gas leak: LG Polymers’ Vizag plant produced stuff used to make disposable plastic cutlery

The Vizag plant manufactures polystyrene (PS) that finds wide utility in the food-service industry as rigid trays and containers, disposable utensils, and foamed cups, plates and bowls.




polymer

LG Polymers says vapour leak caused accident at Vizag plant

The firm said a special task force has been set up to help victims and families to resolve any issues and provide every assistance to the bereaved families.




polymer

Global Corrosion Protection Polymer Coating Market 2020 Key Players Analysis, Segmentation, Growth, Future Trend, Gross ...

(MENAFN - CDN Newswire) A report added to the rich database of MarketsandResearch.biz , titled [To enable links in your articles, contact MENAFN Cl... ......




polymer

Global Hermosetting Polymers Market 2020 Key Players Analysis, Segmentation, Growth, Future Trend, Gross Margin, Demand ...

(MENAFN - CDN Newswire) MarketsandResearch.biz has recently published a research report titled, Global Hermosetting Polymers Market 2020 by Manufact... ......




polymer

At least 11 dead, hundreds injured after chemical gas leak at LG Polymers plant in India

A gas leaked from an LG chemical plant in southern India early on Thursday, leaving people struggling to breathe and collapsing in the streets as they tried to flee. At least 11 people died and about 1,000 suffered breathing difficulties and other problems.The synthetic chemical styrene leaked from the LG Polymers plant in a city on India’s eastern coast while workers were preparing to restart the facility after a coronavirus lockdown was eased, state official Vinay Chand said.A fire that broke…




polymer

Gas leak at LG Polymers plant in India kills at least 9

A gas leak at an LG Polymers plant in India has been brought under control, and the company is investigating the cause of the deadly accident and the extent of the damage, South Korea's LG Chem, the owner of the plant, said in a statement.




polymer

Protesters demand closure of LG Polymers plant in India after toxic gas leak

Villagers placed the bodies of three victims of a deadly gas leak from an LG Polymers plant in southern India at the gates of the site on Saturday, and demanded the factory be shut down immediately and its top management arrested.




polymer

Norovirus Replication in Human Intestinal Epithelial Cells Is Restricted by the Interferon-Induced JAK/STAT Signaling Pathway and RNA Polymerase II-Mediated Transcriptional Responses

ABSTRACT

Human noroviruses (HuNoV) are a leading cause of viral gastroenteritis worldwide and a significant cause of morbidity and mortality in all age groups. The recent finding that HuNoV can be propagated in B cells and mucosa-derived intestinal epithelial organoids (IEOs) has transformed our ability to dissect the life cycle of noroviruses. Using transcriptome sequencing (RNA-Seq) of HuNoV-infected intestinal epithelial cells (IECs), we have found that replication of HuNoV in IECs results in interferon (IFN)-induced transcriptional responses and that HuNoV replication in IECs is sensitive to IFN. This contrasts with previous studies that suggested that the innate immune response may play no role in the restriction of HuNoV replication in immortalized cells. We demonstrated that inhibition of Janus kinase 1 (JAK1)/JAK2 enhanced HuNoV replication in IECs. Surprisingly, targeted inhibition of cellular RNA polymerase II-mediated transcription was not detrimental to HuNoV replication but instead enhanced replication to a greater degree than blocking of JAK signaling directly. Furthermore, we demonstrated for the first time that IECs generated from genetically modified intestinal organoids, engineered to be deficient in the interferon response, were more permissive to HuNoV infection. Taking the results together, our work revealed that IFN-induced transcriptional responses restrict HuNoV replication in IECs and demonstrated that inhibition of these responses mediated by modifications of the culture conditions can greatly enhance the robustness of the norovirus culture system.

IMPORTANCE Noroviruses are a major cause of gastroenteritis worldwide, and yet the challenges associated with their growth in culture have greatly hampered the development of therapeutic approaches and have limited our understanding of the cellular pathways that control infection. Here, we show that human intestinal epithelial cells, which represent the first point of entry of human noroviruses into the host, limit virus replication by induction of innate responses. Furthermore, we show that modulating the ability of intestinal epithelial cells to induce transcriptional responses to HuNoV infection can significantly enhance human norovirus replication in culture. Collectively, our findings provide new insights into the biological pathways that control norovirus infection but also identify mechanisms that enhance the robustness of norovirus culture.




polymer

The streptococcal multidomain fibrillar adhesin CshA has an elongated polymeric architecture [Microbiology]

The cell surfaces of many bacteria carry filamentous polypeptides termed adhesins that enable binding to both biotic and abiotic surfaces. Surface adherence is facilitated by the exquisite selectivity of the adhesins for their cognate ligands or receptors and is a key step in niche or host colonization and pathogenicity. Streptococcus gordonii is a primary colonizer of the human oral cavity and an opportunistic pathogen, as well as a leading cause of infective endocarditis in humans. The fibrillar adhesin CshA is an important determinant of S. gordonii adherence, forming peritrichous fibrils on its surface that bind host cells and other microorganisms. CshA possesses a distinctive multidomain architecture comprising an N-terminal target-binding region fused to 17 repeat domains (RDs) that are each ∼100 amino acids long. Here, using structural and biophysical methods, we demonstrate that the intact CshA repeat region (CshA_RD1–17, domains 1–17) forms an extended polymeric monomer in solution. We recombinantly produced a subset of CshA RDs and found that they differ in stability and unfolding behavior. The NMR structure of CshA_RD13 revealed a hitherto unreported all β-fold, flanked by disordered interdomain linkers. These findings, in tandem with complementary hydrodynamic studies of CshA_RD1–17, indicate that this polypeptide possesses a highly unusual dynamic transitory structure characterized by alternating regions of order and disorder. This architecture provides flexibility for the adhesive tip of the CshA fibril to maintain bacterial attachment that withstands shear forces within the human host. It may also help mitigate deleterious folding events between neighboring RDs that share significant structural identity without compromising mechanical stability.




polymer

Recombinase Polymerase Amplification and Lateral Flow Assay for Ultrasensitive Detection of Low-Density Plasmodium falciparum Infection from Controlled Human Malaria Infection Studies and Naturally Acquired Infections [Parasitology]

Microscopy and rapid diagnostic tests (RDTs) are the main diagnostic tools for malaria but fail to detect low-density parasitemias that are important for maintaining malaria transmission. To complement existing diagnostic methods, an isothermal reverse transcription-recombinase polymerase amplification and lateral flow assay (RT-RPA) was developed. We compared the performance with that of ultrasensitive reverse transcription-quantitative PCR (uRT-qPCR) using nucleic acid extracts from blood samples (n = 114) obtained after standardized controlled human malaria infection (CHMI) with Plasmodium falciparum sporozoites. As a preliminary investigation, we also sampled asymptomatic individuals (n = 28) in an area of malaria endemicity (Lambaréné, Gabon) to validate RT-RPA and assess its performance with unprocessed blood samples (dbRT-RPA). In 114 samples analyzed from CHMI trials, the positive percent agreement to uRT-qPCR was 90% (95% confidence interval [CI], 80 to 96). The negative percent agreement was 100% (95% CI, 92 to 100). The lower limit of detection was 64 parasites/ml. In Gabon, RT-RPA was 100% accurate with asymptomatic volunteers (n = 28), while simplified dbRT-RPA showed 89% accuracy. In a subgroup analysis, RT-RPA detected 9/10 RT-qPCR-positive samples, while loop-mediated isothermal amplification (LAMP) detected 2/10. RT-RPA is a reliable diagnostic test for asymptomatic low-density infections. It is particularly useful in settings where uRT-qPCR is difficult to implement.




polymer

Development of a Sensitive and Rapid Recombinase Polymerase Amplification Assay for Detection of Anaplasma phagocytophilum [Chlamydiology and Rickettsiology]

Human granulocytic anaplasmosis (HGA) is a tick-borne disease caused by the obligate intracellular Gram-negative bacterium Anaplasma phagocytophilum. The disease often presents with nonspecific symptoms with negative serology during the acute phase. Direct pathogen detection is the best approach for early confirmatory diagnosis. Over the years, PCR-based molecular detection methods have been developed, but optimal sensitivity is not achieved by conventional PCR while real-time PCR requires expensive and sophisticated instruments. To improve the sensitivity and also develop an assay that can be used in resource-limited areas, an isothermal DNA amplification assay based on recombinase polymerase amplification (RPA) was developed. To do this, we identified a 171-bp DNA sequence within multiple paralogous copies of msp2 within the genome of A. phagocytophilum. Our novel RPA assay targeting this sequence has an analytical limit of detection of one genome equivalent copy of A. phagocytophilum and can reliably detect 125 bacteria/ml in human blood. A high level of specificity was demonstrated by the absence of nonspecific amplification using genomic DNA from human or DNA from other closely-related pathogenic bacteria, such as Anaplasma platys, Ehrlichia chaffeensis, Orientia tsutsugamushi, and Rickettsia rickettsii, etc. When applied to patient DNA extracted from whole blood, this new RPA assay was able to detect 100% of previously diagnosed A. phagocytophilum cases. The sensitivity and rapidness of this assay represents a major improvement for early diagnosis of A. phagocytophilum in human patients and suggest a role for better surveillance in its reservoirs or vectors, especially in remote regions where resources are limited.




polymer

FAK regulates actin polymerization during sperm capacitation via the ERK2/GEF-H1/RhoA signaling pathway [RESEARCH ARTICLE]

Monica L. Salgado-Lucio, Danelia Ramirez-Ramirez, Coral Y. Jorge-Cruz, Ana L. Roa-Espitia, and Enrique O. Hernandez-Gonzalez

Actin polymerization is a crucial process during sperm capacitation. We have recently described the participation of FAK during actin polymerization in guinea pig spermatozoa. However, the mechanism by which FAK mediates these processes is unknown. Our previous data have shown that MAPK1 (hereafter referred to as ERK2) is activated during the first minutes of capacitation, and inhibition of ERK2 blocked actin polymerization and the acrosome reaction. In this current study, we found that FAK is involved in ERK2 activation – as FAK was phosphorylated at tyrosine residue 925 and bound to Grb2 – and that inhibition of FAK results in a significant decrease of ERK2 activation. We also confirmed the presence of Rho guanine nucleotide exchange factor 2 (ARHGEF2, hereafter referred to as GEF-H1), which is able to associate with RhoA during capacitation. RhoA activation and its participation in actin polymerization were also analyzed. Inhibition of FAK or ERK1/2 impeded GEF-H1 phosphorylation, RhoA activation, and the association between GEF-H1 and RhoA. Finally, we observed the presence of fibronectin on the sperm surface, its role in sperm–sperm interaction as well as participation of β-integrin in the activation of ERK2. Our results show that the signaling pathway downstream of fibronectin, via integrin, FAK, Grb2, MEK1/2, ERK2, GEF-H1 and RhoA regulates the actin polymerization associated with spermatozoa capacitation.




polymer

E. coli DNA Polymerase I and the Klenow Fragment

Escherichia coli DNA Pol I can carry out three enzymatic reactions: It possesses 5' -> 3' DNA polymerase activity and 3' -> 5' and 5' -> 3' exonuclease activity. Pol I can be cleaved by mild treatment with subtilisin into two fragments; the larger fragment is known as the Klenow fragment. The Klenow fragment retains the polymerizing activity and the 3' -> 5' exonuclease of the holo-enzyme but lacks its powerful 5' -> 3' exonuclease activity. These enzymes and their applications in molecular cloning are introduced here.




polymer

Labeling 3' Termini of Double-Stranded DNA Using the Klenow Fragment of E. coli DNA Polymerase I

The Klenow fragment, which retains the template-dependent deoxynucleotide polymerizing activity and the 3' -> 5' exonuclease of the holo-enzyme but lacks its powerful 5' -> 3' exonuclease activity, is used to fill recessed 3' termini of dsDNA. In this protocol, fragments suitable as templates for the end-filling reaction are produced by digestion of DNA with an appropriate restriction enzyme. The Klenow enzyme is then used to catalyze the attachment of dNTPs to the recessed 3'-hydroxyl groups.




polymer

Sensitive Determination of Infectious Titer of Recombinant Adeno-Associated Viruses (rAAVs) Using TCID50 End-Point Dilution and Quantitative Polymerase Chain Reaction (qPCR)

Adeno-associated virus (AAV) recombinants are currently the vector of choice for many gene therapy applications. As experimental therapies progress to clinical trials, the need to characterize recombinant adeno-associated viruses (rAAVs) accurately and reproducibly increases. Accurate determination of rAAV infectious titer is important for determining the activity of each vector lot and for ensuring lot-to-lot consistency. The following protocol developed in our laboratory uses a 96-well TCID50 format and quantitative polymerase chain reaction (qPCR) detection for the determination of rAAV infectious titer.




polymer

Titration of Recombinant Adeno-Associated Virus (rAAV) Genome Copy Number Using Real-Time Quantitative Polymerase Chain Reaction (qPCR)

This protocol is used to determine the concentration of DNase-resistant vector genomes (i.e., packaged in the capsid) in purified recombinant adeno-associated virus (rAAV) preparations. The protocol begins with treatment of the vector stock with DNase I to eliminate unencapsidated AAV DNA or contaminating plasmid DNA. This is followed by a heat treatment to heat-inactivate DNase I, to disrupt the viral capsid, and to release the packaged vector genomes for quantification by real-time polymerase chain reaction (PCR) using a set of standards (linearized plasmid used for vector production) containing known copy numbers. To accomplish high-throughput titration, the primer and probe sets used in real-time PCR are usually designed to target common elements present in most rAAV genomes, such as promoters and poly(A) signals. This strategy significantly reduces the number of PCRs, controls, and turnaround time. Several important controls should be included in the assay as follows: The first two controls should have a known copy number of the rAAV genome plasmid treated or not treated with DNase I. This control tests the effectiveness of DNase treatment. To control for potential cross-contamination between samples during the preparation process, a blank control containing nuclease-free water only should be processed and tested in parallel. A validation vector sample with a known titer should be included in every assay to monitor interassay variability. Finally, for the PCR run, a no-template control (NTC) is included to indicate cross-contamination during PCR setup.




polymer

Protesters demand closure of LG Polymers plant in India after toxic gas leak




polymer

Protesters demand closure of LG Polymers plant in India after toxic gas leak

Villagers placed the bodies of three victims of a deadly gas leak from an LG Polymers plant in southern India at the gates of the site on Saturday, and demanded the factory be shut down immediately and its top management arrested.




polymer

Gas leak at LG Polymers plant in India kills 11, hospitalises hundreds

At least 11 people have been killed and hundreds more are in hospital after a chemical gas leak at an LG Polymers plant in southern India.



  • Disasters and Accidents
  • Government and Politics
  • Death
  • Pollution
  • Disasters and Safety
  • Oil and Gas

polymer

India faces dual crises as LG Polymers gas leak kills at least 11




polymer

Yokogawa Takes a Stake in All Polymer Battery Maker APB to Drive Expansion of Energy Management System Business

Yokogawa Electric Corporation (TOKYO: 6841) announces that it has acquired capital in APB Corporation (APB), a pioneer in the development of a next-generation lithium-ion battery called the “All Polymer Battery,” with the aim of growing Yokogawa’s energy management system (EMS) business. The two companies have agreed that Yokogawa will provide energy management technology needed for the efficient operation and optimization of large-scale storage batteries.




polymer

Natural polyphenol assisted delivery of single-strand oligonucleotides by cationic polymers




polymer

Fatal gas leak hits India's LG Polymers plant