bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cellular distribution of alkaloids and their translocation via phloem and xylem: the importance of compartment pH
Authors: Nowak M. , Selmar D. 
Published: September 2016

AbstractThe physico‐chemical background of alkaloid allocation within plants is outlined and discussed exemplarily for pyrrolizidine alkaloids (PAs) and nicotine. The trigger for this discourse is the finding that, for example, PAs, which are taken up from the soil, are translocated in the xylem, whereas – when genuinely present in plants – they are allocated as N‐oxides via phloem. Special emphasis is put on the impact of different pH values in certain compartments, as this entails significant changes in the relative lipophilic character of alkaloids: tertiary alkaloids diffuse readily through biomembranes, while the corresponding protonated alkaloids are retained in acidic compartments, i.e. vacuoles or xylem. Therefore, this phenomenon, well known as the ‘ion trap mechanism’, is also relevant for long‐distance transport of alkaloids. Any efficient allocation of typical tertiary alkaloids within the phloem can thus be excluded. In contrast, due to their strongly increased hydrophilic properties, alkaloid‐N‐oxides or quarternary alkaloids cannot diffuse through biomembranes and, consequently, would be retained in the acidic xylem during translocation. The major aim of this paper is to sharpen the mind for the chemical peculiarities of alkaloids and to consider them adequately in forthcoming investigations on allocation of alkaloids.
Retailers and Consumers: The Pass‐through of Import Price Changes
Authors: Berner Eike , Birg Laura , Boddin Dominik 
Published: September 2016

AbstractIn this paper, we estimate pass‐through rates of import price changes to retail prices across retailers and consumers for apparel purchases in Germany for the period of 2000–07. We find that high‐price retailers do not pass through changes in the import price. Pass‐through rates for low‐price retailers are 53 per cent within three months. Consequently, pass‐through rates for low‐income households are 58 per cent, significantly larger than those for high‐income households. We then present one possible explanation for these observations in a theoretical model with endogenous vertical product differentiation due to bundling an ex ante homogeneous import goods with services. Following an import price change, retailers who sell a cheaper unbundled product change prices to a greater extent than retailers who sell a higher‐priced bundle of product and service.
Two cases of feline paraneoplastic alopecia associated with a neuroendocrine pancreatic neoplasia and a hepatosplenic plasma cell tumour
Authors: Caporali Chiara , Albanese Francesco , Binanti Diana , Abramo Francesca 
Published: September 2016

BackgroundFeline paraneoplastic alopecia (FPA) is a rare condition listed among the cutaneous paraneoplastic syndromes, which occurs in association with pancreatic carcinoma, cholangiocarcinoma, hepatocellular carcinoma and metastatic intestinal carcinoma.ObjectivesTo describe the clinicopathological findings of paraneoplastic alopecia in two cats each with an uncommon tumour not previously reported in association withFPA.AnimalsParaneoplastic alopecia was associated with neuroendocrine pancreatic neoplasia in a Persian cat and with a hepatosplenic plasma cell tumour in a domestic short hair cat.ResultsFPAwas suspected based on age, rapid onset of clinical signs, ventral distribution of alopecia, shiny appearance of the skin and telogenization/miniaturization of the follicles on histopathology. The nature of the tumours was determined through cytology, postmortem, histopathological and immunohistochemical examination, and capillary immunoelectrophoresis. A causative association between the skin lesions and the tumour was suggested by clinical and histopathological features shared with previously published cases.Conclusions and clinical importancePancreatic neuroendocrine and plasma cell tumour should be considered as differential diagnoses when evaluatingFPA.
Integrative analysis of miRNA and mRNA paired expression profiling of primary fibroblast derived from diabetic foot ulcers reveals multiple impaired cellular functions
Authors: Liang Liang , Stone Rivka C. , Stojadinovic Olivera , Ramirez Horacio , Pastar Irena , Maione Anna G. , Smith Avi , Yanez Vanessa , Veves Aristides , Kirsner Robert S. , Garlick Jonathan A. , Tomic‐Canic Marjana 
Published: September 2016

ABSTRACTDiabetic foot ulcers (DFUs) are one of the major complications of diabetes. Its molecular pathology remains poorly understood, impeding the development of effective treatments. Although it has been established that multiple cell types, including fibroblasts, keratinocytes, macrophages, and endothelial cells, all contribute to inhibition of healing, less is known regarding contributions of individual cell type. Thus, we generated primary fibroblasts from nonhealing DFUs and evaluated their cellular and molecular properties in comparison to nondiabetic foot fibroblasts (NFFs). Specifically, we analyzed both micro‐RNA and mRNA expression profiles of primary DFU fibroblasts. Paired genomic analyses identified a total of 331 reciprocal miRNA–mRNA pairs including 21 miRNAs (FC > 2.0) along with 239 predicted target genes (FC > 1.5) that are significantly and differentially expressed. Of these, we focused on three miRNAs (miR‐21‐5p, miR‐34a‐5p, miR‐145‐5p) that were induced in DFU fibroblasts as most differentially regulated. The involvement of these microRNAs in wound healing was investigated by testing the expression of their downstream targets as well as by quantifying cellular behaviors in prospectively collected and generated cell lines from 15 patients (seven DFUF and eight NFF samples). We found large number of downstream targets of miR‐21‐5p, miR‐34a‐5p, miR‐145‐5p to be coordinately regulated in mRNA profiles, which was confirmed by quantitative real‐time PCR. Pathway analysis on paired miRNA–mRNA profiles predicted inhibition of cell movement and cell proliferation, as well as activation of cell differentiation and senescence in DFU fibroblasts, which was confirmed by cellular assays. We concluded that induction of miR‐21‐5p, miR‐34a‐5p, miR‐145‐5p in DFU dermal fibroblasts plays an important role in impairing multiple cellular functions, thus contributing to overall inhibition of healing in DFUs.
Molecular Epidemiology of Staphylococcus aureus in the General Population in Northeast Germany: Results of the Study of Health in Pomerania (SHIP-TREND-0)
Authors: Holtfreter Silva , Grumann Dorothee , Balau Veronika , Barwich Annette , Kolata Julia , Goehler André , Weiss Stefan , Holtfreter Birte , Bauerfeind Stephanie S. , Döring Paula , Friebe Erika , Haasler Nicole , Henselin Kristin , Kühn Katrin , Nowotny Sophie , Radke Dörte , Schulz Katrin , Schulz Sebastian R. , Trübe Patricia , Vu Chi Hai , Walther Birgit , Westphal Susanne , Cuny Christiane , Witte Wolfgang , Völzke Henry , Grabe Hans Jörgen , Kocher Thomas , Steinmetz Ivo , Bröker Barbara M. 
Published: September 2016

ABSTRACT

Population-based studies on
Staphylococcus aureus
nasal colonization are scarce. We examined the prevalence, resistance, and molecular diversity of
S. aureus
in the general population in Northeast Germany. Nasal swabs were obtained from 3,891 adults in the large-scale population-based Study of Health in Pomerania (SHIP-TREND). Isolates were characterized using
spa
genotyping, as well as antibiotic resistance and virulence gene profiling. We observed an
S. aureus
prevalence of 27.2%. Nasal
S. aureus
carriage was associated with male sex and inversely correlated with age. Methicillin-resistant
S. aureus
(MRSA) accounted for 0.95% of the colonizing
S. aureus
strains. MRSA carriage was associated with frequent visits to hospitals, nursing homes, or retirement homes within the previous 24 months. All MRSA strains were resistant to multiple antibiotics. Most MRSA isolates belonged to the pandemic European hospital-acquired MRSA sequence type 22 (HA-MRSA-ST22) lineage. We also detected one livestock-associated MRSA ST398 (LA-MRSA-ST398) isolate, as well as six livestock-associated methicillin-susceptible
S. aureus
(LA-MSSA) isolates (clonal complex 1 [CC1], CC97, and CC398).
spa
typing revealed a diverse but also highly clonal
S. aureus
population structure. We identified a total of 357
spa
types, which were grouped into 30 CCs or sequence types. The major seven CCs (CC30, CC45, CC15, CC8, CC7, CC22, and CC25) included 75% of all isolates. Virulence gene patterns were strongly linked to the clonal background. In conclusion, MSSA and MRSA prevalences and the molecular diversity of
S. aureus
in Northeast Germany are consistent with those of other European countries. The detection of HA-MRSA and LA-MRSA within the general population indicates possible transmission from hospitals and livestock, respectively, and should be closely monitored.
Discrimination of Aspergillosis, Mucormycosis, Fusariosis, and Scedosporiosis in Formalin-Fixed Paraffin-Embedded Tissue Specimens by Use of Multiple Real-Time Quantitative PCR Assays
Authors: Salehi Elham , Hedayati Mohammad T. , Zoll Jan , Rafati Haleh , Ghasemi Maryam , Doroudinia Atosa , Abastabar Mahdi , Tolooe Ali , Snelders Eveline , van der Lee Henrich A. , Rijs Antonius J. M. M. , Verweij Paul E. , Seyedmousavi Seyedmojtaba , Melchers Willem J. G. 
Published: September 2016

ABSTRACT

In a retrospective multicenter study, 102 formalin-fixed paraffin-embedded (FFPE) tissue specimens with histopathology results were tested. Two 4- to 5-μm FFPE tissue sections from each specimen were digested with proteinase K, followed by automated nucleic acid extraction. Multiple real-time quantitative PCR (qPCR) assays targeting the internal transcribed spacer 2 (ITS2) region of ribosomal DNA, using fluorescently labeled primers, was performed to identify clinically important genera and species of
Aspergillus
,
Fusarium
,
Scedosporium
, and the
Mucormycetes
. The molecular identification was correlated with results from histological examination. One of the main findings of our study was the high sensitivity of the automated DNA extraction method, which was estimated to be 94%. The qPCR procedure that was evaluated identified a range of fungal genera/species, including
Aspergillus fumigatus
,
Aspergillus flavus
,
Aspergillus terreus
,
Aspergillus niger
,
Fusarium oxysporum
,
Fusarium solani
,
Scedosporium apiospermum
,
Rhizopus oryzae
,
Rhizopus microsporus
,
Mucor
spp., and
Syncephalastrum
.
Fusarium oxysporum
and
F. solani
DNA was amplified from five specimens from patients initially diagnosed by histopathology as having aspergillosis.
Aspergillus flavus
,
S. apiospermum
, and
Syncephalastrum
were detected from histopathological mucormycosis samples. In addition, examination of four samples from patients suspected of having concomitant aspergillosis and mucormycosis infections resulted in the identification of two
A. flavus
isolates, one
Mucor
isolate, and only one sample having both
R. oryzae
and
A. flavus
. Our results indicate that histopathological features of molds may be easily confused in tissue sections. The qPCR assay used in this study is a reliable tool for the rapid and accurate identification of fungal pathogens to the genus and species levels directly from FFPE tissues.
Canonical and Variant Forms of Histone H3 Are Deposited onto the Human Cytomegalovirus Genome during Lytic and Latent Infections
Authors: Albright Emily R. , Kalejta Robert F. 
Published: September 2016

ABSTRACT

Chromatin is the nucleoprotein complex that protects and compacts eukaryotic genomes. It is responsible for a large part of the epigenetic control of transcription. The genomes of DNA viruses such as human cytomegalovirus (HCMV) are devoid of histones within virions but are chromatinized and epigenetically regulated following delivery to the host cell nucleus. How chromatin is initially assembled on viral genomes and which variant forms of the core histone proteins are deposited are incompletely understood. We monitored the deposition of both ectopically expressed and endogenous histones H3.1 and H3.2 (collectively, H3.1/2) and H3.3 during lytic and latent HCMV infections. Here, we show that they are deposited on HCMV genomes during lytic and latent infections, suggesting similar mechanisms of viral chromatin assembly during the different infection types and indicating that both canonical and variant core histones may be important modulators of infecting viral genomes. We further show that association of both H3.1/2 and H3.3 occurs independent of viral DNA synthesis or
de novo
viral gene expression, implicating cellular factors and/or virion components in the formation of chromatin on virion-delivered genomes during both lytic and latent infections.

IMPORTANCE
It is well established that infecting herpesvirus genomes are chromatinized upon entry into the host cell nucleus. Why or how this occurs is a mystery. It is important to know why they are chromatinized in order to better understand cellular pathogen recognition (DNA sensing) pathways and viral fate determinations (lytic or latent) and to anticipate how artificially modulating chromatinization may impact viral infections. It is important to know how the genomes are chromatinized in order to potentially modulate the process for therapeutic effect. Our work showing that HCMV genomes are loaded with canonical and variant H3 histones during both lytic and latent infections strengthens the hypothesis that chromatinization pathways are similar between the two infection types, implicates virion or cellular factors in this process, and exposes the possibility that histone variants, in addition to posttranslational modification, may impact viral gene expression. These revelations are important to understanding and intelligently intervening in herpesvirus infections.
Activation of the RLR/MAVS Signaling Pathway by the L Protein of Mopeia Virus
Authors: Zhang Lei-Ke , Xin Qi-Lin , Zhu Sheng-Lin , Wan Wei-Wei , Wang Wei , Xiao Gengfu 
Published: September 2016

ABSTRACT

The family
Arenaviridae
includes several important human pathogens that can cause severe hemorrhagic fever and greatly threaten public health. As a major component of the innate immune system, the RLR/MAVS signaling pathway is involved in recognizing viral components and initiating antiviral activity. It has been reported that arenavirus infection can suppress the innate immune response, and NP and Z proteins of pathogenic arenaviruses can disrupt RLR/MAVS signaling, thus inhibiting production of type I interferon (IFN-I). However, recent studies have shown elevated IFN-I levels in certain arenavirus-infected cells. The mechanism by which arenavirus infection induces IFN-I responses remains unclear. In this study, we determined that the L polymerase (Lp) of Mopeia virus (MOPV), an Old World (OW) arenavirus, can activate the RLR/MAVS pathway and thus induce the production of IFN-I. This activation is associated with the RNA-dependent RNA polymerase activity of Lp. This study provides a foundation for further studies of interactions between arenaviruses and the innate immune system and for the elucidation of arenavirus pathogenesis.

IMPORTANCE
Distinct innate immune responses are observed when hosts are infected with different arenaviruses. It has been widely accepted that NP and certain Z proteins of arenaviruses inhibit the RLR/MAVS signaling pathway. The viral components responsible for the activation of the RLR/MAVS signaling pathway remain to be determined. In the current study, we demonstrate for the first time that the Lp of MOPV, an OW arenavirus, can activate the RLR/MAVS signaling pathway and thus induce the production of IFN-I. Based on our results, we proposed that dynamic interactions exist among Lp-produced RNA, NP, and the RLR/MAVS signaling pathway, and the outcome of these interactions may determine the final IFN-I response pattern: elevated or reduced. Our study provides a possible explanation for how IFN-I can become activated during arenavirus infection and may help us gain insights into the interactions that form between different arenavirus components and the innate immune system.
Mitogen-Activated Protein Kinase Kinase 2, a Novel E2-Interacting Protein, Promotes the Growth of Classical Swine Fever Virus via Attenuation of the JAK-STAT Signaling Pathway
Authors: Wang Jinghan , Chen Shucheng , Liao Yajin , Zhang Enyu , Feng Shuo , Yu Shaoxiong , Li Lian-Feng , He Wen-Rui , Li Yongfeng , Luo Yuzi , Sun Yuan , Zhou Mo , Wang Xiao , Munir Muhammad , Li Su , Qiu Hua-Ji 
Published: September 2016

ABSTRACT

The mitogen-activated protein kinase kinase/extracellular regulated kinase (MEK1/2/ERK1/2) cascade is involved in the replication of several members of the
Flaviviridae
family, including hepatitis C virus and dengue virus. The effects of the cascade on the replication of classical swine fever virus (CSFV), a fatal pestivirus of pigs, remain unknown. In this study, MEK2 was identified as a novel binding partner of the E2 protein of CSFV using yeast two-hybrid screening. The E2-MEK2 interaction was confirmed by glutathione
S
-transferase pulldown, coimmunoprecipitation, and laser confocal microscopy assays. The C termini of E2 (amino acids [aa] 890 to 1053) and MEK2 (aa 266 to 400) were mapped to be crucial for the interaction. Overexpression of MEK2 significantly promoted the replication of CSFV, whereas knockdown of MEK2 by lentivirus-mediated small hairpin RNAs dramatically inhibited CSFV replication. In addition, CSFV infection induced a biphasic activation of ERK1/2, the downstream signaling molecules of MEK2. Furthermore, the replication of CSFV was markedly inhibited in PK-15 cells treated with U0126, a specific inhibitor for MEK1/2/ERK1/2, whereas MEK2 did not affect CSFV replication after blocking the interferon-induced Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway by ruxolitinib, a JAK-STAT-specific inhibitor. Taken together, our results indicate that MEK2 positively regulates the replication of CSFV through inhibiting the JAK-STAT signaling pathway.

IMPORTANCE
Mitogen-activated protein kinase kinase 2 (MEK2) is a kinase that operates immediately upstream of extracellular regulated kinase 1/2 (ERK1/2) and links to Raf and ERK via phosphorylation. Currently, little is known about the role of MEK2 in the replication of classical swine fever virus (CSFV), a devastating porcine pestivirus. Here, we investigated the roles of MEK2 and the MEK2/ERK1/2 cascade in the growth of CSFV for the first time. We show that MEK2 positively regulates CSFV replication. Notably, we demonstrate that MEK2 promotes CSFV replication through inhibiting the interferon-induced JAK-STAT signaling pathway, a key antiviral pathway involved in innate immunity. Our work reveals a novel role of MEK2 in CSFV infection and sheds light on the molecular basis by which pestiviruses interact with the host cell.
Role of LAMP1 Binding and pH Sensing by the Spike Complex of Lassa Virus
Authors: Cohen-Dvashi Hadas , Israeli Hadar , Shani Orly , Katz Aliza , Diskin Ron 
Published: September 2016

ABSTRACT

To effectively infect cells, Lassa virus needs to switch in an endosomal compartment from its primary receptor, α-dystroglycan, to a protein termed LAMP1. A unique histidine triad on the surface of the receptor-binding domain from the glycoprotein spike complex of Lassa virus is important for LAMP1 binding. Here we investigate mutated spikes that have an impaired ability to interact with LAMP1 and show that although LAMP1 is important for efficient infectivity, it is not required for spike-mediated membrane fusion
per se
. Our studies reveal important regulatory roles for histidines from the triad in sensing acidic pH and preventing premature spike triggering. We further show that LAMP1 requires a positively charged His230 residue to engage with the spike complex and that LAMP1 binding promotes membrane fusion. These results elucidate the molecular role of LAMP1 binding during Lassa virus cell entry and provide new insights into how pH is sensed by the spike.

IMPORTANCE
Lassa virus is a devastating disease-causing agent in West Africa, with a significant yearly death toll and severe long-term complications associated with its infection in survivors. In recent years, we learned that Lassa virus needs to switch receptors in a pH-dependent manner to efficiently infect cells, but neither the molecular mechanisms that allow switching nor the actual effects of switching were known. Here we investigate the activity of the viral spike complex after abrogation of its ability to switch receptors. These studies inform us about the role of switching receptors and provide new insights into how the spike senses acidic pH.
Characterization of Vesicular Stomatitis Virus Pseudotypes Bearing Essential Entry Glycoproteins gB, gD, gH, and gL of Herpes Simplex Virus 1
Authors: Rogalin Henry B. , Heldwein Ekaterina E. 
Published: September 2016

ABSTRACT
Herpes simplex viruses (HSVs) are unusual in that unlike most enveloped viruses, they require at least four entry glycoproteins, gB, gD, gH, and gL, for entry into target cells in addition to a cellular receptor for gD. The dissection of the herpes simplex virus 1 (HSV-1) entry mechanism is complicated by the presence of more than a dozen proteins on the viral envelope. To investigate HSV-1 entry requirements in a simplified system, we generated vesicular stomatitis virus (VSV) virions pseudotyped with HSV-1 essential entry glycoproteins gB, gD, gH, and gL but lacking the native VSV fusogen G. These virions, referred to here as VSVΔG-BHLD virions, infected a cell line expressing a gD receptor, demonstrating for the first time that the four essential entry glycoproteins of HSV-1 are not only required but also sufficient for cell entry. To our knowledge, this is the first time the VSV pseudotyping system has been successfully extended beyond two proteins. Entry of pseudotyped virions required a gD receptor and was inhibited by HSV-1 specific anti-gB or anti-gH/gL neutralizing antibodies, which suggests that membrane fusion during the entry of the pseudotyped virions shares common requirements with the membrane fusion involved in HSV-1 entry and HSV-1-mediated syncytium formation. The HSV pseudotyping system established in this study presents a novel tool for systematic exploration of the HSV entry and membrane fusion mechanisms.

IMPORTANCE
Herpes simplex viruses (HSVs) are human pathogens that can cause cold sores, genital herpes, and blindness. No vaccines or preventatives are available. HSV entry into cells—a prerequisite for a successful infection—is a complex process that involves multiple viral and host proteins and occurs by different routes. Detailed mechanistic knowledge of the HSV entry is important for understanding its pathogenesis and would benefit antiviral and vaccine development, yet the presence of more than a dozen proteins on the viral envelope complicates the dissection of the HSV entry mechanisms. In this study, we generated heterologous virions displaying the four essential entry proteins of HSV-1 and showed that they are capable of cell entry and, like HSV-1, require all four entry glycoproteins along with a gD receptor. This HSV pseudotyping system pioneered in this work opens doors for future systematic exploration of the herpesvirus entry mechanisms.