bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent Trends in Clinicians Providing Care to Pregnant Women in the United States
Authors: Kozhimannil Katy Backes , Avery Melissa D. , Terrell Carrie Ann 
Published: September 2012

Introduction: Health care needs of pregnant women are met by a variety of clinicians in a changing policy and practice environment. This study documents recent trends in types of clinicians providing care to pregnant women in the United States.Methods: We used a repeat cross‐sectional design and data from the Integrated Health Interview Series (2000‐2009), a nationally representative data set, for respondents who reported being pregnant at the time of the survey (N = 3204). Using longitudinal logistic regression models, we analyzed changes over time in pregnant women's reported use of care from 1) obstetrician‐gynecologists; 2) midwives, nurse practitioners (NPs), or physician assistants (PAs); or 3) both an obstetrician‐gynecologist and a midwife, NP, or PA.Results: The percentage of pregnant women who reported seeing an obstetrician‐gynecologist (87%) remained steady from 2000 through 2009. After controlling for demographic and clinical variables, the percentage who reported receiving care from a midwife, NP, or PA increased 4% annually (yearly adjusted odds ratio [AOR] 1.04; P < .001), indicating a cumulative increase of 48% over the decade. The percentage of pregnant women who received care from both an obstetrician‐gynecologist and a midwife, NP, or PA also increased (AOR 1.027; P < .001), for a cumulative increase of 30%.Discussion: The increasing role of midwives, NPs, and PAs in the provision of maternity care suggests changes in the perinatal workforce and practice models that may promote collaborative care and quality improvement. However, better data collection is required to gather detailed information on specific provider types, these trends, and their implications.
Effect of ZrO2 (YPSZ) on Microstructure Characteristic and Wear Resistance of the Ti3Al/TiC Laser‐Cladded Ceramic Layer on Titanium Alloy
Authors: Li Jianing , Chen Chuanzhong 
Published: September 2012

Laser cladding of the A3Ti + TiC preplaced powders on the Ti–6Al–4V alloy can form the Ti3Al/TiC ceramic layer, which improved the wear resistance of the substrate. In this study, the influence of 7 wt% yttria partially stabilized zirconia (YPSZ) on the surface performance of the Ti3Al/TiC ceramic layer was researched, and the Al3Ti + TiC/YPSZ laser‐cladded coating has been researched by means of X‐ray diffraction, scanning electron microscope, and energy dispersive spectrometer. It was found that laser cladding of YPSZ can control the cracks in the Ti3Al/TiC ceramic layer. Furthermore, due to the action of YPSZ, stratification was observed in this ceramic layer. The upper layer in this coating consisted of Al2O3, Ti3Al, t‐ZrO2, TiC, TiO2 and ZrSiO4, and Ti3Al/Al2O3 were the matrix of this region. This upper layer exhibited an excellent wear resistance due to its phase constituent. During the cladding process, YPSZ had a very marked trend to float on the surface of the coating. Therefore, the upper layer showed better wear resistance than that of the bottom layer due to the action of the high YPSZ content.
Exploitation and conservation of fish genetic resources in Africa: issues and priorities for aquaculture development and research
Authors: Lind Curtis E. , Brummett Randall E. , Ponzoni Raul W. 
Published: September 2012

AbstractAfrica harbours a rich biological diversity of native fish resources. Recognition of the potential to use these resources to make significant contributions towards improving African food security through aquaculture has existed for some time. A key challenge, however, is achieving compatibility between the two urgent, but sometimes conflicting, goals of reducing poverty and food insecurity in Africa through aquaculture development while paying due attention to the conservation of natural biodiversity and fish genetic resources (FiGR). In this paper we highlight the overarching challenges concerning the conservation and exploitation of FiGR for the long‐term development of aquaculture for food production in Africa. We address the major issues requiring attention in genetic improvement programs in order to take full advantage of the highly diverse wild FiGR in Africa, and we expand on strategies such as zoning, environmental risk analysis and molecular characterization approaches that can be used to minimize the potential harm to wild FiGR arising from aquaculture activities and future development. Finally, we discuss the challenge of strengthening local capacity. The enhancement of local capacity is essential because it will enable the fundamental link required to achieve the desired outcome of increasing the productivity of aquatic animals for food in Africa in a sustainable manner. We trust that this paper will provide a good basis for an in‐depth discussion of the subject, as well as guidance on future research and development priorities for the compatible exploitation and conservation of FiGR in Africa.
Canine Trypanosoma evansi infection introduced into Germany
Authors: Defontis Myriam , Richartz Janina , Engelmann Nina , Bauer Christian , Schwierk Viktoria Maria , Büscher Philippe , Moritz Andreas 
Published: September 2012

AbstractA 9‐year‐old male Jack Russell Terrier with a history of travel to Thailand was presented with chronic lethargy, weight loss, unilateral anterior uveitis, pancytopenia, hyperglobulinemia, and proteinuria. Numerous trypomastigotes were found on a blood smear, and using molecular methods the parasite was identified as Trypanosoma evansi. After initial response to treatment, the dog experienced a relapse with central neurologic signs 88 days after initial presentation and died. Antibodies to T evansi were detected in both serum and cerebrospinal fluid (CSF) using a card agglutination test (CATT/T evansi), and PCR analysis of CSF for T evansi was positive. Findings at necropsy included marked non‐purulent meningoencephalitis. Chronic infection with T evansi in a dog that returned to Germany following international travel highlights the risk associated with introduction of foreign animal diseases to Europe and the possibility of these infections becoming endemic. Detection of chronic infection and curative therapy of trypanosomiasis are challenging, and infection is usually fatal in the dog.
Development of an Inhalational Bacillus anthracis Exposure Therapeutic Model in Cynomolgus Macaques
Authors: Henning Lisa N. , Comer Jason E. , Stark Gregory V. , Ray Bryan D. , Tordoff Kevin P. , Knostman Katherine A. B. , Meister Gabriel T. 
Published: September 2012

ABSTRACTAppropriate animal models are required to test medical countermeasures to bioterrorist threats. To that end, we characterized a nonhuman primate (NHP) inhalational anthrax therapeutic model for use in testing anthrax therapeutic medical countermeasures according to the U.S. Food and Drug Administration Animal Rule. A clinical profile was recorded for each NHP exposed to a lethal dose ofBacillus anthracisAmes spores. Specific diagnostic parameters were detected relatively early in disease progression, i.e., by blood culture (∼37 h postchallenge) and the presence of circulating protective antigen (PA) detected by electrochemiluminescence (ECL) ∼38 h postchallenge, whereas nonspecific clinical signs of disease, i.e., changes in body temperature, hematologic parameters (ca. 52 to 66 h), and clinical observations, were delayed. To determine whether the presentation of antigenemia (PA in the blood) was an appropriate trigger for therapeutic intervention, a monoclonal antibody specific for PA was administered to 12 additional animals after the circulating levels of PA were detected by ECL. Seventy-five percent of the monoclonal antibody-treated animals survived compared to 17% of the untreated controls, suggesting that intervention at the onset of antigenemia is an appropriate treatment trigger for this model. Moreover, the onset of antigenemia correlated with bacteremia, and NHPs were treated in a therapeutic manner. Interestingly, brain lesions were observed by histopathology in the treated nonsurviving animals, whereas this observation was absent from 90% of the nonsurviving untreated animals. Our results support the use of the cynomolgus macaque as an appropriate therapeutic animal model for assessing the efficacy of medical countermeasures developed against anthrax when administered after a confirmation of infection.
Antibody Responses to Individual Bordetella pertussis Fimbrial Antigen Fim2 or Fim3 following Immunization with the Five-Component Acellular Pertussis Vaccine or to Pertussis Disease
Authors: Alexander Frances , Matheson Mary , Fry Norman K. , Labram Briony , Gorringe Andrew R. 
Published: September 2012

ABSTRACTBordetella pertussisexpresses two serologically distinct fimbriae (Fim2 and Fim3) which are included in the Sanofi Pasteur 5-component acellular pertussis vaccine, and antibody responses to these antigens have been shown to be associated with protection. Studies to date have assessed the IgG response to this vaccine using a copurified mixture of Fim2 and Fim3, and the response to the individual antigens has not been characterized. We have purified separate Fim2 and Fim3 from strains that express either Fim2 or Fim3 and have used these antigens in an enzyme-linked immunosorbent assay (ELISA) to quantify IgG responses following immunization with 5-component acellular pertussis vaccine in 15-month-old, 4- to 6-year-old, and 11- to 18-year-old subjects. All individuals showed increases in Fim2 and Fim3 IgG concentrations following immunization, with 3-fold-greater Fim2 than Fim3 IgG concentrations seen in the younger two age groups. Fim2 IgG concentrations were 1.5-fold greater than Fim3 IgG concentrations in the 11- to 18-year-olds. We have also compared Fim2 and Fim3 IgG concentrations in individuals with prolonged cough who were diagnosed as having recent pertussis using a pertussis toxin (Ptx) IgG ELISA with individuals with prolonged cough but without elevated Ptx IgG concentrations. Individuals with evidence of recent pertussis had greater Fim3 IgG concentrations, consistent with the predominant serotype of isolates obtained in the United Kingdom. However, a surprising number of individuals had moderate Fim2 IgG concentrations despite very few isolates of that serotype obtained in the sampling period.
Ten Years of External Quality Assessment of Human Immunodeficiency Virus Type 1 RNA Quantification
Authors: Senechal Brigitte , James Vivienne L. A. 
Published: September 2012

ABSTRACT

Viral load testing is an essential parameter in guiding antiretroviral therapy for individuals infected with human immunodeficiency virus type 1 (HIV-1). An external quality assessment scheme for the molecular quantification of HIV-1 RNA was introduced by the United Kingdom National External Quality Assessment Service for Microbiology in 2000. Specimen pairs of freeze-dried plasma were distributed to a median of 141 participants three times a year. The aim of this study was to analyze the quantification of HIV-1 RNA results between 2000 and 2010. Overall variability, measured by the standard deviations of all viral load results for each specimen, was below 0.5 log copy/ml (
n
= 48). When we compared assay results, the medians of the viral load by assay were within a range of 0.25 to 1.08 log copies/ml, with the lowest median values being consistently reported with the Siemens branched-chain DNA assay. The spread of participant results and, hence, differences between assay medians were greater when quantifying non-B subtypes. Laboratories were scored on the proximity of their reported log difference for the specimen pair to the median log difference reported by all laboratories. The overall level of performance with the HIV-1 RNA specimens over the past 10 years has been consistently good, with more than 90% of the participants reporting in the accepted range (median difference, ±0.5 log unit). Future distributions may result in tightening the acceptance levels of quantification and the use of more challenging specimens, including a variety of subtypes, with developments focusing on maintaining the clinical relevance and educational value of the scheme.
Distribution and Phosphorylation of the Basic Protein P6.9 of Autographa californica Nucleopolyhedrovirus
Authors: Liu XiaoXiao , Zhao Haizhou , Fang Zhixin , Yuan Meijin , Yang Kai , Pang Yi 
Published: September 2012

ABSTRACT

A protamine-like protein named P6.9 is thought to play a role in the condensation of genomes of the baculovirus
Autographa californica
multiple nucleopolyhedrovirus (AcMNPV) during an infection. Previous studies have shown that P6.9 is phosphorylated immediately upon synthesis and dephosphorylated upon the entry of the P6.9-DNA complex into the capsid. Here, we investigate the dynamic distribution of P6.9 in AcMNPV-infected
Spodoptera frugiperda
cells using an influenza virus hemagglutinin (HA)-tagged P6.9. Although a portion of P6.9-HA localized to the virogenic stroma, which is the center of viral DNA replication, transcription, and nucleocapsid assembly, the majority of P6.9-HA was distributed near the inner nuclear membrane throughout the course of infection. Antiserum against P6.9 detected specific phosphorylated forms of P6.9 at the edge of, but not within, the electron-dense matte regions of the virogenic stroma. Further analysis using immunoblotting revealed that at least 11 different phosphorylated forms of P6.9, as well as dephosphorylated P6.9, were present in association with occlusion-derived virions, although only dephosphorylated P6.9 was associated with budded virions.
Zinc Finger Antiviral Protein Inhibits Murine Gammaherpesvirus 68 M2 Expression and Regulates Viral Latency in Cultured Cells
Authors: Xuan Yifang , Liu Ling , Shen Sheng , Deng Hongyu , Gao Guangxia 
Published: September 2012

ABSTRACT
Zinc finger antiviral protein (ZAP) is a host factor that specifically inhibits the replication of certain viruses by binding to specific viral mRNAs and repressing mRNA expression. Here we report that ZAP inhibits expression of murine gammaherpesvirus 68 (MHV-68) M2, which plays important roles in establishment and maintenance of viral latency. Downregulation of endogenous ZAP in cells harboring latent MHV-68 promoted lytic replication of the virus. These results suggest that ZAP inhibits M2 expression and regulates the maintenance of MHV-68 latency.
Structure of Crimean-Congo Hemorrhagic Fever Virus Nucleoprotein: Superhelical Homo-Oligomers and the Role of Caspase-3 Cleavage
Authors: Wang Yi , Dutta Sujit , Karlberg Helen , Devignot Stéphanie , Weber Friedemann , Hao Quan , Tan Yee Joo , Mirazimi Ali , Kotaka Masayo 
Published: September 2012

ABSTRACTCrimean-Congo hemorrhagic fever, a severe hemorrhagic disease found throughout Africa, Europe, and Asia, is caused by the tick-borne Crimean-Congo hemorrhagic fever virus (CCHFV). CCHFV is a negative-sense single-stranded RNA (ssRNA) virus belonging to theNairovirusgenus of theBunyaviridaefamily. Its genome of three single-stranded RNA segments is encapsidated by the nucleocapsid protein (CCHFV N) to form the ribonucleoprotein complex. This ribonucleoprotein complex is required during replication and transcription of the viral genomic RNA. Here, we present the crystal structures of the CCHFV N in two distinct forms, an oligomeric form comprised of double antiparallel superhelices and a monomeric form. The head-to-tail interaction of the stalk region of one CCHFV N subunit with the base of the globular body of the adjacent subunit stabilizes the helical organization of the oligomeric form of CCHFV N. It also masks the conserved caspase-3 cleavage site present at the tip of the stalk region from host cell caspase-3 interaction and cleavage. By incubation with primer-length ssRNAs, we also obtained the crystal structure of CCHFV N in its monomeric form, which is similar to a recently published structure. The conformational change of CCHFV N upon deoligomerization results in the exposure of the caspase-3 cleavage site and subjects CCHFV N to caspase-3 cleavage. Mutations of this cleavage site inhibit cleavage by caspase-3 and result in enhanced viral polymerase activity. Thus, cleavage of CCHFV N by host cell caspase-3 appears to be crucial for controlling viral RNA synthesis and represents an important host defense mechanism against CCHFV infection.
In Vitro
Quantification of the Relative Packaging Efficiencies of Single-Stranded RNA Molecules by Viral Capsid Protein
Authors: Comas-Garcia Mauricio , Cadena-Nava Ruben D. , Rao A. L. N. , Knobler Charles M. , Gelbart William M. 
Published: September 2012

ABSTRACT

While most T=3 single-stranded RNA (ssRNA) viruses package
in vivo
about 3,000 nucleotides (nt),
in vitro
experiments have demonstrated that a broad range of RNA lengths can be packaged. Under the right solution conditions, for example, cowpea chlorotic mottle viru
s
(CCMV) capsid protein (CP) has been shown to package RNA molecules whose lengths range from 100 to 10,000 nt. Furthermore, in each case it can package the RNA completely, as long as the mass ratio of CP to nucleic acid in the assembly mixture is 6:1 or higher. Yet the packaging efficiencies of the RNAs can differ widely, as we demonstrate by measurements in which two RNAs compete head-to-head for a limited amount of CP. We show that the relative efficiency depends nonmonotonically on the RNA length, with 3,200 nt being optimum for packaging by the T=3 capsids preferred by CCMV CP. When two RNAs of the same length—and hence the same charge—compete for CP, differences in packaging efficiency are necessarily due to differences in their secondary structures and/or three-dimensional (3D) sizes. For example, the heterologous RNA1 of brome mosaic virus (BMV) is packaged three times more efficiently by CCMV CP than is RNA1 of CCMV, even though the two RNAs have virtually identical lengths. Finally, we show that in an assembly mixture at neutral pH, CP binds reversibly to the RNA and there is a reversible equilibrium between all the various RNA/CP complexes. At acidic pH, excess protein unbinds from RNA/CP complexes and nucleocapsids form irreversibly.
Persistence of Epstein-Barr Virus in Self-Reactive Memory B Cells
Authors: Tracy Sean I. , Kakalacheva Kristina , Lünemann Jan D. , Luzuriaga Katherine , Middeldorp Jaap , Thorley-Lawson David A. 
Published: September 2012

ABSTRACT

Epstein-Barr virus infection has been epidemiologically associated with the development of multiple autoimmune diseases, particularly systemic lupus erythematosus and multiple sclerosis. Currently, there is no known mechanism that can account for these associations. The germinal-center (GC) model of EBV infection and persistence proposes that EBV gains access to the memory B cell compartment via GC reactions by driving infected cells to differentiate using the virus-encoded LMP1 and LMP2a proteins, which act as functional homologues of CD40 and the B cell receptor, respectively. The ability of LMP2a, when expressed in mice, to allow escape of autoreactive B cells suggests that it could perform a similar role in infected GC B cells, permitting the survival of potentially pathogenic autoreactive B cells. To test this hypothesis, we cloned and expressed antibodies from EBV
+
and EBV
−
memory B cells present during acute infection and profiled their self- and polyreactivity. We find that EBV does persist within self- and polyreactive B cells but find no evidence that it favors the survival of pathogenic autoreactive B cells. On the contrary, EBV
+
memory B cells express lower levels of self-reactive and especially polyreactive antibodies than their uninfected counterparts do. Our work suggests that EBV has only a modest effect on the GC process, which allows it to access and persist within a subtly unique niche of the memory compartment characterized by relatively low levels of self- and polyreactivity. We suggest that this might reflect an active process where EBV and its human host have coevolved so as to minimize the virus's potential to contribute to autoimmune disease.
Deletion of the Herpes Simplex Virus 1 U
L
49 Gene Results in mRNA and Protein Translation Defects That Are Complemented by Secondary Mutations in U
L
41
Authors: Mbong Ekaette F. , Woodley Lucille , Dunkerley Eric , Schrimpf Jane E. , Morrison Lynda A. , Duffy Carol 
Published: September 2012

ABSTRACT

Herpes simplex virus 1 (HSV-1) virions, like those of all herpesviruses, contain a protein layer termed the tegument localized between the capsid and the envelope. VP22, encoded by the U
L
49 gene, is one of the most abundant tegument proteins in HSV-1 virions. Studies with a U
L
49-null mutant showed that the absence of VP22 resulted in decreased protein synthesis at late times in infection. VP22 is known to form a tripartite complex with VP16 and vhs through direct interactions with VP16. Given that U
L
49-null mutants have been shown to acquire spontaneous secondary mutations in the U
L
41 gene, which encodes vhs, we hypothesized that VP22 and vhs may play antagonistic roles during HSV-1 infections. In the present study, we show that the protein synthesis defect observed in U
L
49-null virus infections was rescued by a secondary, compensatory frameshift mutation in U
L
41. A double mutant bearing a deletion of U
L
49 and a point mutation in vhs previously shown to specifically abrogate vhs's RNase activity also resulted in a rescue of protein synthesis. To determine whether the U
L
49
−
protein synthesis defect, and the rescue by secondary mutations in vhs, occurred at the mRNA and/or translational levels, quantitative reverse transcriptase PCR (qRT-PCR) and polysome analyses were performed. We found that the absence of VP22 caused a small decrease in mRNA levels as well as a defect in polysome assembly that was independent of mRNA abundance. Both defects were complemented by the secondary mutations in vhs, indicating functional interplay between VP22 and vhs in both accumulation and translation of viral mRNAs.
Pathways to a rising caesarean section rate: a population-based cohort study
Authors: Roberts Christine L , Algert Charles S , Ford Jane B , Todd Angela L , Morris Jonathan M 
Published: September 2012

ObjectivesTo determine whether the obstetric pathways leading to caesarean section changed from one decade to another. We also aimed to explore how much of the increase in caesarean rate could be attributed to maternal and pregnancy factors including a shift towards delivery in private hospitals.DesignPopulation-based record linkage cohort study.SettingNew South Wales, Australia.ParticipantsFor annual rates, all women giving birth in NSW during 1994 to 2009 were included. To examine changes in obstetric pathways two cohorts were compared: all women with a first-birth during either 1994–1997 (82 988 women) or 2001–2004 (85 859 women) and who had a second (sequential) birth within 5 years of their first-birth.Primary outcome measuresCaesarean section rates, by parity and onset of labour.ResultsFor first-births, prelabour and intrapartum caesarean rates increased from 1994 to 2009, with intrapartum rates rising from 6.5% to 11.7%. This fed into repeat caesarean rates; from 2003, over 18% of all multiparous births were prelabour repeat caesareans. In the 1994–1997 cohort, 17.7% of women had a caesarean delivery for their first-birth. For their second birth, the vaginal birth after caesarean (VBAC) rate was 28%. In the 2001–2004 cohort, 26.1% of women had a caesarean delivery for their first-birth and the VBAC rate was 16%. Among women with a first-birth, maternal and pregnancy factors and increasing deliveries in private hospitals, only explained 24% of the rise in caesarean rates from 1994 to 2009.ConclusionsRising first-birth caesarean rates drove the overall increase. Maternal factors and changes in public/private care could explain only a quarter of the increase. Changes in the perceived risks of vaginal birth versus caesarean delivery may be influencing the pregnancy management decisions of clinicians and/or mothers.