bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exploration of the functional hierarchy of the basal layer of human epidermis at the single‐cell level using parallel clonal microcultures of keratinocytes
Authors: Fortunel Nicolas O. , Cadio Emmanuelle , Vaigot Pierre , Chadli Loubna , Moratille Sandra , Bouet Stéphan , Roméo Paul‐Henri , Martin Michèle T. 
Published: February 2010

Please cite this paper as: Exploration of the functional hierarchy of the basal layer of human epidermis at the single‐cell level using parallel clonal microcultures of keratinocytes. Experimental Dermatology 2010.Abstract:  The basal layer of human epidermis contains both stem cells and keratinocyte progenitors. Because of this cellular heterogeneity, the development of methods suitable for investigations at a clonal level is dramatically needed. Here, we describe a new method that allows multi‐parallel clonal cultures of basal keratinocytes. Immediately after extraction from tissue samples, cells are sorted by flow cytometry based on their high integrin‐α6 expression and plated individually in microculture wells. This automated cell deposition process enables large‐scale characterization of primary clonogenic capacities. The resulting clonal growth profile provided a precise assessment of basal keratinocyte hierarchy, as the size distribution of 14‐day‐old clones ranged from abortive to highly proliferative clones containing 1.7 × 105 keratinocytes (17.4 cell doublings). Importantly, these 14‐day‐old primary clones could be used to generate three‐dimensional reconstructed epidermis with the progeny of a single cell. In long‐term cultures, a fraction of highly proliferative clones could sustain extensive expansion of >100 population doublings over 14 weeks and exhibited long‐term epidermis reconstruction potency, thus fulfilling candidate stem cell functional criteria. In summary, parallel clonal microcultures provide a relevant model for single‐cell studies on interfollicular keratinocytes, which could be also used in other epithelial models, including hair follicle and cornea. The data obtained using this system support the hierarchical model of basal keratinocyte organization in human interfollicular epidermis.
The mouse frizzy (fr) and rat ‘hairless’ (frCR) mutations are natural variants of protease serine S1 family member 8 (Prss8)
Authors: Spacek Damek V. , Perez Amarilis F. , Ferranti Katelynn M. , Wu Lillya K.‐L. , Moy Daniel M. , Magnan David R. , King Thomas R. 
Published: February 2010

Please cite this paper as: The mouse frizzy (fr) and rat ‘hairless’ (frCR) mutations are natural variants of protease serine S1 family member 8 (Prss8). Experimental Dermatology 2010; 19: 527–532.Abstract:  We have previously suggested (based on genetic mapping analysis) that the allelic ‘fuzzy’ and ‘hairless’ mutations in the rat are likely orthologues of the mouse frizzy mutation (fr). Here, we analysed three large intraspecific backcross panels that segregated for mouse fr to restrict this locus to a 0.6‐Mb region that includes fewer than 30 genes. DNA sequencing of one of these candidates known to be expressed in skin, protease serine S1 family member 8 (Prss8), revealed a T to A transversion associated with the fr allele that would result in a valine to aspartate substitution at residue 170 in the gene product. To test whether this missense mutation might be the molecular basis of this frizzy variant, we crossed fr/fr mice with mice that carried a recessive perinatal lethal mutation in Prss8. Hybrid offspring that inherited both fr and the Prss8 null allele displayed abnormal hair and skin, showing that these two mutations are allelic, and suggesting strongly that the T to A mutation in Prss8 is responsible for the mutant frizzy phenotype. Sequence analysis of all Prss8 coding regions in the ‘hairless’ rat identified a 12‐bp deletion in the third exon, indicating that mouse fr and the rat ‘hairless’ mutations are indeed orthologues. However, this analysis failed to detect any alterations to Prss8 coding sequences in the allelic ‘fuzzy’ rat variant.
Analysis of DEFB1 regulatory SNPs in cystic fibrosis patients from North‐Eastern Italy
Authors: Segat L. , Morgutti M. , Athanasakis E. , Trevisiol C. , Amaddeo A. , Poli F. , Crovella S. 
Published: February 2010

SummaryCystic fibrosis (CF) transmembrane regulator protein (CFTR) gene is undoubtedly the main genetic factor involved in the modulation of CF phenotype. However, other factors such as human defensins and the genes encoding for these antimicrobial peptides have been hypothesized as possible modifiers influencing airways infection in CF patients, but their role in the pathogenesis of lung disease is still debated. Since DEFB1 gene encoding for human beta‐defensin 1 displays features such as antimicrobial or chemotactic activity playing a role in inflammation, it has been considered as a possible candidate CF modifier gene. We analysed three single nucleotide polymorphisms (SNPs) in the 5′‐untranslated region of the DEFB1 gene (namely g‐52G>A, g‐44C>G and g‐20G>A) in a group of 62 CF patients from North Eastern Italy, and in 130 healthy controls, with the aim of verifying the possible association of these functional SNPs with the pulmonary phenotype of CF patients. DEFB1 SNPs have been genotyped by using Taqman allele‐specific fluorescent probes and a real‐time PCR platform. No significant differences were found for allele, genotype and haplotype frequencies of DEFB1 g‐52G>A, g‐44C>G and g‐20G>A SNPs in CF patients stratified for Pseudomonas aeruginosa infection, as well as in patients with a severe and mild clinical phenotype or in patients stratified for CFTR genotypes. DEFB1 allele, genotype and haplotype frequencies of CF patients globally considered were similar to those of healthy controls. Our findings are discordant with respect to another recent study performed on CF patients coming from Southern Italy, probably due to different ethnicity of the patients.
Association of mannose‐binding lectin polymorphisms and HBV outcome in a South Indian population
Authors: Fletcher G. J. , Gnanamony M. , Samuel P. , Ismail A. M. , Kannangai R. , Daniel D. , Eapen C. E. , Abraham P. 
Published: February 2010

SummaryMannose binding lectin (MBL) is an important innate immune system pattern recognition molecule. The MBL gene polymorphisms are reported to play a crucial role in outcome of hepatitis B virus (HBV) infection. In this study, we ascertained the association of MBL genotypes with HBV outcome in a South Indian population. The MBL gene polymorphisms at codons 52, 54 and 57 of exon I, and promoter polymorphisms at −221 were typed by polymerase chain reaction‐sequence specific primer in spontaneously recovered and in chronic HBV group. The allele frequency of codon 52 ‘C’ was significantly higher in chronic HBV group than in the recovered group (98.5% vs. 93.6%; P = 0.003) and codon 52 ‘T’ was significantly higher in recovered group than in the chronic group (6.4% vs. 1.5%; P = 0.003). In multivariate analysis, after adjusting for age, sex and state of origin, codon 52 ‘CC’ and ‘CT’ genotypes were significantly associated with chronicity and recovery respectively [odds ratio (OR), 0.25; 95% confidence interval (CI), 0.08–0.80, P = 0.02] in co‐dominant analyzing models. This was re‐affirmed in analysis performed exclusively on Tamil Nadu subjects (OR, 0.23; 95% CI, 0.06–0.93, P = 0.039). The frequency of low/none haplotype (XY/O) was significantly higher in recovered group than in chronic group (15.6% vs 7.5%) and associated with spontaneous recovery (OR, 2.28; 95% CI, 1.04–4.99, P = 0.035). Our results provide preliminary evidence that inheritance of codon 52 genotypes and XY/O haplotype associated with low MBL level substantially determine the outcome of HBV infection in a sympatrically isolated South Indian population.
Male-specific induction of CYP3A2 in rats by zolmitriptan
Authors: Yu Lushan , Lu Sijie , Zhao Naping , Ni Shaoqing , Yao Tongwei , Zeng Su 
Published: February 2010

AbstractWe report here a novel observation that zolmitriptan induced CYP3A2 in male but not female rats. As part of our research programme to evaluate sex differences in the response to zolmitriptan, we studied the effects of zolmitriptan on CYP3A activity, protein and gene expression in male and female rats. Zolmitriptan was found to induce CYP3A activity, measured as testosterone and diazepam metabolism in-vitro, as well as midazolam pharmacokinetics in-vivo, in male but not female rats. The sex difference in response to zolmitriptan was further evaluated by analysis of CYP3A1/2 mRNA levels using real-time PCR, and CYP3A1/2 protein levels using immunoblotting. Zolmitriptan preferentially induced CYP3A2 in male but not female rats. No obvious effects on CYP3A1 were observed at any dose in either sex. Thus, we concluded that the observed sex-dependent induction of CYP3A by zolmitriptan was largely due to induction of CYP3A2 in male rats.
Fatal
Citrobacter farmeri
Meningitis in a Patient with Nasopharyngeal Cancer
Authors: Tan Che-Kim , Lai Chih-Cheng , Lin Sheng-Hsiang , Liao Chun-Hsing , Huang Yu-Tsung , Hsueh Po-Ren 
Published: February 2010

ABSTRACT

We describe the case of an adult male with nasopharyngeal carcinoma who had meningitis caused by
Citrobacter farmeri
. The isolate was confirmed as
C. farmeri
by two commercial identification systems and 16S rRNA gene analysis. The patient developed multiorgan failure and died despite antibiotic treatment with
in vitro
active agents (ceftriaxone and meropenem).
Staphylococcus aureus
Antimicrobial Susceptibility of Abscess Samples from Adults and Children from the Kaleida Health System in Western New York State, 2003 to 2006
Authors: Hsiao Chiu-Bin , Dryja Diane , Abbatessa Laurie , Patel Pravin H. 
Published: February 2010

ABSTRACT

Staphylococcus aureus
is the most common etiologic agent of skin abscesses. The regional rate of methicillin-resistant
S. aureus
(MRSA) abscesses may reflect the prevalence of local community-acquired MRSA (CAMRSA). A retrospective study was conducted to compare the antimicrobial susceptibility patterns of
S. aureus
isolates recovered from abscesses from 2003 to 2006 from patients at hospitals of the Kaleida Health System in western New York.
S. aureus
susceptibility information was obtained from a Vitek Legacy system, and the location and source of each isolate were identified. EpiInfo software was used to analyze the antimicrobial susceptibilities of all isolates and the trends in the rates of MRSA. A total of 2,848
S. aureus
abscesses were identified by the Kaleida Health Clinical Microbiology Laboratory. Of those, 978
S. aureus
abscess events occurred in four hospitals, including three adult facilities (547 episodes with 62 cases of bacteremia) and one children's facility (431 episodes with 2 cases of bacteremia). The MRSA rates in adults increased from 56% (2003) to 71% (2006), and that in children increased from 26% (2003) to 64% (2006). Of the MRSA isolates in the children's samples, more than 92% were susceptible to clindamycin. Of the MRSA isolates in the adult samples, 50% were susceptible to clindamycin in 2003 and 2004, whereas greater than 75% were susceptible in 2005 and 2006. The increased rates of MRSA abscesses with susceptibility to clindamycin may reflect the high prevalence level of CAMRSA in the western New York community. The variations in
S. aureus
susceptibilities could serve as an indicator of the changing resistance patterns within a broad urban community.
Comparison of the BD GeneOhm Methicillin-Resistant
Staphylococcus aureus
(MRSA) PCR Assay to Culture by Use of BBL CHROMagar MRSA for Detection of MRSA in Nasal Surveillance Cultures from Intensive Care Unit Patients
Authors: Snyder James W. , Munier Gina K. , Johnson Charles L. 
Published: February 2010

ABSTRACT

This study compared the BD GeneOhm methicillin-resistant
Staphylococcus aureus
(MRSA) real-time PCR assay to culture by the use of BBL CHROMagar MRSA for the detection of MRSA in 627 nasal surveillance specimens collected from intensive care unit (ICU) patients. The PCR assay had a sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 96.7%, 70.3%, and 100%, respectively. Nine of 19 false-positive PCR specimens grew methicillin-susceptible
S. aureus
(MSSA) from broth enrichment culture, of which two demonstrated evidence of
mec
A
gene dropout. Compared to culture by the use of BBL CHROMagar MRSA, the BD GeneOhm MRSA PCR assay demonstrated sensitivity and specificity above 95% for the detection of MRSA nasal colonization and provided shorter turnaround time in generating positive and negative final results.
Controlling False-Positive Results Obtained with the Hodge and Masuda Assays for Detection of Class A Carbapenemase in Species of
Enterobacteriaceae
by Incorporating Boronic Acid
Authors: Pasteran Fernando , Mendez Tania , Rapoport Melina , Guerriero Leonor , Corso Alejandra 
Published: February 2010

ABSTRACT

The modified Hodge method (MHT) has been recommended by the CLSI for confirmation of suspected class A carbapenemase production in species of
Enterobacteriaceae
. This test and the Masuda method (MAS) have advantages over traditional phenotypic methods in that they directly analyze carbapenemase activity. In order to identify the potential interferences of these tests, we designed a panel composed of diverse bacterial genera with distinct carbapenem susceptibility patterns (42 carbapenemase producers and 48 nonproducers). About 25% of results among carbapenemase nonproducers, mainly strains harboring CTX-M and AmpC hyperproducers, were observed to be false positive. Subsequently, we developed an optimized approach for more-accurate detection of suspicious isolates of carbapenemase by addition of boronic acid (BA) derivatives (reversible inhibitor of class A carbapenemases and AmpC cephalosporinases) and oxacillin (inhibitor of AmpCs enzymes). The use of the modified BA- and oxacillin-based MHT and MAS resulted in high sensitivity (>90%) and specificity (100%) for class A carbapenemase detection. By use of these methodologies, isolates producing KPCs and GES, Sme, IMI, and NMC-A carbapenemases were successfully distinguished from those producing other classes of ß-lactamases (extended-spectrum β-lactamases [ESBLs], AmpC β-lactamases, metallo-β-lactamases [MBLs], etc.). These methods will provide the fast and useful information needed for targeting of antimicrobial therapy and appropriate infection control.
Prevalence and Characteristics of the O122 Pathogenicity Island in Typical and Atypical Enteropathogenic
Escherichia coli
Strains
Authors: Vieira Mônica A. M. , Salvador Fábia A. , Silva Rosa M. , Irino Kinue , Vaz Tânia M. I. , Rockstroh Anna C. , Guth Beatriz E. C. , Gomes Tânia A. T. 
Published: February 2010

ABSTRACT

The presence of the pathogenicity island (PAI) O122 genes,
efa1
(
lifA
),
sen
,
pagC
,
nleB
, and
nleE
, in typical and atypical enteropathogenic
Escherichia coli
(EPEC) strains was investigated. The simultaneous occurrence of all genes was statistically associated with diarrhea due to atypical EPEC. Detection of the complete PAI O122 could aid in the identification of potential pathogenic strains of atypical EPEC.
Identification of
Francisella tularensis
by Whole-Cell Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry: Fast, Reliable, Robust, and Cost-Effective Differentiation on Species and Subspecies Levels
Authors: Seibold E. , Maier T. , Kostrzewa M. , Zeman E. , Splettstoesser W. 
Published: February 2010

ABSTRACT

Francisella tularensis
, the causative agent of tularemia, is a potential agent of bioterrorism. The phenotypic discrimination of closely related, but differently virulent,
Francisella tularensis
subspecies with phenotyping methods is difficult and time-consuming, often producing ambiguous results. As a fast and simple alternative, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) was applied to 50 different strains of the genus
Francisella
to assess its ability to identify and discriminate between strains according to their designated species and subspecies. Reference spectra from five representative strains of
Francisella philomiragia
,
Francisella tularensis
subsp.
tularensis
,
Francisella tularensis
subsp.
holarctica
,
Francisella tularensis
subsp.
mediasiatica
, and
Francisella tularensis
subsp.
novicida
were established and evaluated for their capability to correctly identify
Francisella
species and subspecies by matching a collection of spectra from 45 blind-coded
Francisella
strains against a database containing the five reference spectra and 3,287 spectra from other microorganisms. As a reference method for identification of strains from the genus
Francisella
, 23S rRNA gene sequencing was used. All strains were correctly identified, with both methods showing perfect agreement at the species level as well as at the subspecies level. The identification of
Francisella
strains by MALDI-TOF MS and subsequent database matching was reproducible using biological replicates, different culture media, different cultivation times, different serial
in vitro
passages of the same strain, different preparation protocols, and different mass spectrometers.
Performance of a New Chromogenic Medium, BBL CHROMagar MRSA II (BD), for Detection of Methicillin-Resistant
Staphylococcus aureus
in Screening Samples
Authors: Van Vaerenbergh Kristien , Cartuyvels Reinoud , Coppens Guy , Frans Johan , Van den Abeele Anne-Marie , De Beenhouwer Hans 
Published: February 2010

ABSTRACT
Two chromogenic media for the detection of MRSA were compared: BBL CHROMagar MRSA II (BD) and MRSA ID agar (bioMérieux). Following overnight nonselective enrichment, 1,919 screening samples were inoculated on both chromogenic agars. After 24 h, the sensitivities of both media were high and comparable. Both media showed an important decrease in specificity after 48 h of incubation (decreases of 8% for MRSA II and 10% for MRSA ID), but MRSA II was significantly more specific at both time points.
Association of Schistosomiasis with False-Positive HIV Test Results in an African Adolescent Population
Authors: Everett Dean B. , Baisely Kathy J. , McNerney Ruth , Hambleton Ian , Chirwa Tobias , Ross David A. , Changalucha John , Watson-Jones Deborah , Helmby Helena , Dunne David W. , Mabey David , Hayes Richard J. 
Published: February 2010

ABSTRACT

This study was designed to investigate the factors associated with the high rate of false-positive test results observed with the 4th-generation Murex HIV Ag/Ab Combination EIA (enzyme immunoassay) within an adolescent and young-adult cohort in northwest Tanzania. (4th-generation assays by definition detect both HIV antigen and antibody.) The clinical and sociodemographic factors associated with false-positive HIV results were analyzed for 6,940 Tanzanian adolescents and young adults. A subsample of 284 Murex assay-negative and 240 false-positive serum samples were analyzed for immunological factors, including IgG antibodies to malaria and schistosoma parasites, heterophile antibodies, and rheumatoid factor (RF) titers. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). False-positive HIV test results were associated with evidence of other infections. False positivity was strongly associated with increasing levels of
Schistosoma haematobium
worm IgG1, with adolescents with optical densities in the top quartile being at the highest risk (adjusted OR = 40.7, 95% CI = 8.5 to 194.2 compared with the risk for those in the bottom quartile). False positivity was also significantly associated with increasing
S. mansoni
egg IgG1 titers and RF titers of ≥80 (adjusted OR = 8.2, 95% CI = 2.8 to 24.3). There was a significant negative association between Murex assay false positivity and the levels of
S. mansoni
worm IgG1 and IgG2 and
Plasmodium falciparum
IgG1 and IgG4. In Africa, endemic infections may affect the specificities of immunoassays for HIV infection. Caution should be used when the results of 4th-generation HIV test results are interpreted for African adolescent populations.
Alternative Live-Attenuated Influenza Vaccines Based on Modifications in the Polymerase Genes Protect against Epidemic and Pandemic Flu
Authors: Solórzano Alicia , Ye Jianqiang , Pérez Daniel R. 
Published: February 2010

ABSTRACTHuman influenza is a seasonal disease associated with significant morbidity and mortality. Influenza vaccination is the most effective means for disease prevention. We have previously shown that mutations in the PB1 and PB2 genes of the live-attenuated influenza vaccine (LAIV) from the cold-adapted (ca) influenza virus A/Ann Arbor/6/60 (H2N2) could be transferred to avian influenza viruses and produce partially attenuated viruses. We also demonstrated that avian influenza viruses carrying the PB1 and PB2 mutations could be further attenuated by stably introducing a hemagglutinin (HA) epitope tag in the PB1 gene. In this work, we wanted to determine whether these modifications would also result in attenuation of a so-called triple reassortant (TR) swine influenza virus (SIV). Thus, the TR influenza A/swine/Wisconsin/14094/99 (H3N2) virus was generated by reverse genetics and subsequently mutated in the PB1 and PB2 genes. Here we show that a combination of mutations in this TR backbone results in an attenuated virusin vitroandin vivo. Furthermore, we show the potential of our TR backbone as a vaccine that provides protection against the 2009 swine-origin pandemic influenza H1N1 virus (S-OIV) when carrying the surface of a classical swine strain. We propose that the availability of alternative backbones to the conventionalcaA/Ann Arbor/6/60 LAIV strain could also be useful in epidemic and pandemic influenza and should be considered for influenza vaccine development. In addition, our data provide evidence that the use of these alternative backbones could potentially circumvent the effects of original antigenic sin (OAS) in certain circumstances.
Initiation of Duck Hepatitis B Virus Infection Requires Cleavage by a Furin-Like Protease
Authors: Tong Yupin , Tong Shuping , Zhao Xiaoai , Wang Jianguo , Jun Jenny , Park Joseph , Wands Jack , Li Jisu 
Published: February 2010

ABSTRACT

The entry mechanism of hepatitis B virus (HBV) has not been defined, and this impedes development of antiviral therapies aimed at an early step in the viral life cycle. HBV infection has both host and tissue specificities. For the related duck hepatitis B virus (DHBV), duck carboxypeptidase D (DCPD) has been proposed as the species-specific docking receptor, while glycine decarboxylase (DGD) may serve as a tissue-specific cofactor or secondary receptor. DGD binds to several truncated versions of the viral large envelope protein but not to the full-length protein, suggesting a need for proteolytic cleavage of the envelope protein by a furin-like proprotein convertase. In the present study, we found that transfected DCPD could confer DHBV binding to non-duck cell lines but that this was followed by rapid virus release from cells. Coexpression of furin led to DCPD cleavage and increased virus retention. Treatment of DHBV particles with endosome prepared from duck liver led to cleavage of the large envelope protein, and such viral preparation could generate a small amount of covalently closed circular DNA in LMH cells, a chicken hepatoma cell line resistant to DHBV infection. A furin inhibitor composed of decanoyl-RVKR-chloromethylketone blocked endosomal cleavage of the large envelope protein
in vitro
and suppressed DHBV infection of primary duck hepatocytes
in vivo
. These findings suggest that furin or a furin-like proprotein convertase facilitates DHBV infection by cleaving both the docking receptor and the viral large envelope protein.