bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the Bruker Biotyper and Vitek MS Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry Systems for Identification of Nonfermenting Gram-Negative Bacilli Isolated from Cultures from Cystic Fibrosis Patients
Authors: Marko Daniel C. , Saffert Ryan T. , Cunningham Scott A. , Hyman Jay , Walsh John , Arbefeville Sophie , Howard Wanita , Pruessner Jon , Safwat Nedal , Cockerill Franklin R. , Bossler Aaron D. , Patel Robin , Richter Sandra S.
Published: April 2012

The Bruker Biotyper and Vitek MS matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrometry (MS) instruments were evaluated for the identification of nonfermenting Gram-negative bacilli (NFGNB) by a blinded comparison to conventional biochemical or molecular methods. Two hundred NFGNB that were recovered from cultures from cystic fibrosis patients in the University of Iowa Health Care (UIHC) Microbiology Laboratory between 1 January 2006 and 31 October 2010 were sent to Mayo Clinic for analysis with the Bruker Biotyper (software version 3.0) and to bioMérieux for testing with Vitek MS (SARAMIS database version 3.62). If two attempts at direct colony testing failed to provide an acceptable MALDI-TOF identification, an extraction procedure was performed. The MS identifications from both of these systems were provided to UIHC for comparison to the biochemical or molecular identification that had been reported in the patient record. Isolates with discordant results were analyzed by 16S rRNA gene sequencing at UIHC. After discrepancy testing, the Bruker Biotyper result agreed with the biochemical or molecular method, with 72.5% of isolates to the species level, 5.5% to the complex level, and 19% to the genus level (3% not identified). The level of agreement for Vitek MS was 80% species, 3.5% complex, 6% genus, and 3.5% family (7% not identified). Both MS systems provided rapid (≤3 min per isolate) and reliable identifications. The agreement of combined species/complex/genus-level identification with the reference method was higher for the Bruker Biotyper (97% versus 89.5%,P= 0.004) but required an extraction step more often. Species-level agreement with the reference method was similar for both MS systems (72.5% and 80%,P= 0.099).
Multilocus Variable-Number Tandem-Repeat Analysis Scheme for Chlamydia felis Genotyping: Comparison with Multilocus Sequence Typing
Authors: Laroucau Karine , Di Francesco Antonietta , Vorimore Fabien , Thierry Simon , Pingret Jean Luc , Bertin Claire , Willems Hermann , Bölske Goran , Harley Ross
Published: April 2012

Chlamydia felis
is an important ocular pathogen in cats worldwide. A multilocus variable-number tandem-repeat analysis (MLVA) system for the detection of tandem repeats across the whole genome of
C. felis
strain Fe/C-56 was developed. Nine selected genetic loci were tested by MLVA in 17
C. felis
isolates, including the
C. felis
Baker vaccine strain, and 122 clinical samples from different geographic origins. Analysis of the results identified 25 distinct
C. felis
MLVA patterns. In parallel, a recently described multilocus sequence typing scheme for the typing of
Chlamydia
was applied to 13 clinical samples with 12 different
C. felis
MLVA patterns. Rare sequence differences were observed. Thus, the newly developed MLVA system provides a highly sensitive high-resolution test for the differentiation of
C. felis
isolates from different origins that is suitable for molecular epidemiological studies.
Clinical and Microbiological Characteristics of Bacteremia Caused by Eggerthella, Paraeggerthella, and Eubacterium Species at a University Hospital in Taiwan from 2001 to 2010
Authors: Lee Meng-Rui , Huang Yu-Tsung , Liao Chun-Hsing , Chuang Tzu-Yi , Wang Wei-Jie , Lee Shih-Wei , Lee Li-Na , Hsueh Po-Ren
Published: April 2012

We describe 16 patients with bacteremia caused by
Eggerthella lenta
(
n
= 7),
Paraeggerthella hongkongensis
(
n
= 3),
Eubacterium limosum
(
n
= 4),
Eubacterium callanderi
(
n
= 1), and concomitant
Eubacterium limosum
/
Eggerthella lenta
(
n
= 1). Nine (56%) patients had polymicrobial bacteremia. The overall 60-day mortality rate was 19%, and all deaths occurred in patients with
E. lenta
bacteremia.
Genotyping Reveals the Presence of a Predominant Genotype of Coxiella burnetii in Consumer Milk Products
Authors: Tilburg Jeroen J. H. C. , Roest Hendrik Jan I. J. , Nabuurs-Franssen Marrigje H. , Horrevorts Alphons M. , Klaassen Corné H. W.
Published: April 2012

Real-time PCR shows the widespread presence of
Coxiella burnetii
DNA in a broad range of commercially available milk and milk products. MLVA genotyping shows that this is the result of the presence of a predominant
C. burnetii
genotype in the dairy cattle population.
Genetic Analysis of Cytomegalovirus in Malignant Gliomas
Authors: Bhattacharjee Bornali , Renzette Nicholas , Kowalik Timothy F.
Published: April 2012

Human cytomegalovirus (HCMV) has been found in malignant gliomas at variable frequencies with efforts to date focused on characterizing the role(s) of single gene products in disease. Here, we reexamined the HCMV prevalence in malignant gliomas using different methods and began to dissect the genetics of HCMV in tumors. HCMV DNA was found in 16/17 (94%) tumor specimens. Viral DNA copy numbers were found to be low and variable, ranging from 10
2
to 10
6
copies/500 ng of total DNA. The tumor tissues had incongruences between viral DNA copy numbers and protein levels. However, nonlatent protein expression was detected in many tumors. The viral
UL83
gene, encoding pp65, was found to segregate into five cancer-associated genotypes with a bias for amino acid changes in glioblastoma multiforme (GBM) in comparison to the low-grade tumors. Deep sequencing of a GBM-associated viral population resulted in 81,224 bp of genome coverage. Sequence analysis revealed the presence of intact open reading frames and higher numbers of high-frequency variations within the repeat long region compared to the unique long region, which harbors many core genes, and the unique short region (
P
= 0.001). This observation was in congruence with phylogenetic analyses across replication-competent viral strains in databases. The tumor-associated viral population was less variable (π = 0.1% and π
AA
= 0.08%) than that observed in other clinical infections. Moreover, 42/46 (91.3%) viral genes analyzed had
dN/dS
scores of <1, which is indicative of high amino acid sequence conservation. Taken together, these findings raise the possibility that replication-competent HCMV may exist in malignant gliomas.
Simultaneous Treatment of Human Bronchial Epithelial Cells with Serine and Cysteine Protease Inhibitors Prevents Severe Acute Respiratory Syndrome Coronavirus Entry
Authors: Kawase Miyuki , Shirato Kazuya , van der Hoek Lia , Taguchi Fumihiro , Matsuyama Shutoku
Published: April 2012

The type II transmembrane protease TMPRSS2 activates the spike (S) protein of severe acute respiratory syndrome coronavirus (SARS-CoV) on the cell surface following receptor binding during viral entry into cells. In the absence of TMPRSS2, SARS-CoV achieves cell entry via an endosomal pathway in which cathepsin L may play an important role, i.e., the activation of spike protein fusogenicity. This study shows that a commercial serine protease inhibitor (camostat) partially blocked infection by SARS-CoV and human coronavirus NL63 (HCoV-NL63) in HeLa cells expressing the receptor angiotensin-converting enzyme 2 (ACE2) and TMPRSS2. Simultaneous treatment of the cells with camostat and EST [(23,25)trans-epoxysuccinyl-l-leucylamindo-3-methylbutane ethyl ester], a cathepsin inhibitor, efficiently prevented both cell entry and the multistep growth of SARS-CoV in human Calu-3 airway epithelial cells. This efficient inhibition could be attributed to the dual blockade of entry from the cell surface and through the endosomal pathway. These observations suggest camostat as a candidate antiviral drug to prevent or depress TMPRSS2-dependent infection by SARS-CoV.
Murine Cytomegalovirus Targets Transcription Factor ATF4 To Exploit the Unfolded-Protein Response
Authors: Qian Zhikang , Xuan Baoqin , Chapa Travis J. , Gualberto Nathaniel , Yu Dong
Published: April 2012

The unfolded-protein response (UPR), activated by sensor molecules PERK, ATF6, and IRE1 to resolve endoplasmic reticulum (ER) stress, has emerged as a key target for host cells and viruses to control the infection outcomes. The UPR regulates ER protein folding, controls cell fate upon ER stress, and plays an important role in innate immunity. We and others have shown that human cytomegalovirus (HCMV) modulates the UPR. We show here that murine CMV (MCMV), the widely used CMV model for small animal infection, regulated the UPR in a manner similar to that of HCMV. This modulatory ability was triggered by virion entry and enhanced by viral immediate-early and early gene expression. Thus, while vulnerable at early times, MCMV became resistant to exogenous ER stress at late times of infection. MCMV activated the PERK-ATF4 pathway but only induced a subset of representative ATF4 targets at levels somewhat lower than those by the ER stress inducer tunicamycin. Moreover, MCMV induced ER chaperone Bip but actively blocked IRE1-mediated Xbp1(s) protein accumulation. ATF4 depletion severely attenuated viral growth at a low multiplicity of infection by modestly reducing viral DNA synthesis and more pronouncedly inhibiting late gene transcription. Collectively, we show that the UPR is a conserved target of CMVs and identify ATF4, a key UPR component, as a factor critical for MCMV infection. This work sets the stage for using the MCMV model to explore the role of this stress response in CMV biology, particularly during infection of the host, which is difficult to study in HCMV.
Herpes Simplex Virus Glycoproteins gH/gL and gB Bind Toll-Like Receptor 2, and Soluble gH/gL Is Sufficient To Activate NF-κB
Authors: Leoni Valerio , Gianni Tatiana , Salvioli Stefano , Campadelli-Fiume Gabriella
Published: April 2012

A number of sentinels sense incoming herpes simplex virus (HSV) virions and initiate an immediate innate response. The first line of defense at the cell surface is TLR2 (Toll-like receptor 2), whose signature signaling activity leads to activation of the key transcription factor NF-κB. We report that the HSV pathogen-associated molecular patterns for TLR2 are the virion glycoproteins gH/gL and gB, which constitute the conserved fusion core apparatus across the members of the
Herpesviridae
family. Specifically, virions devoid singly of one of essential fusion glycoproteins (gD, gB, or gH null), able to attach to cells but defective in fusion/entry, were sufficient to elicit the first wave of NF-κB response to HSV. The most effective were the gD-null virions, positive for gH/gL and gB. A soluble form of gB, truncated upstream of the transmembrane sequence (gB
730t-st
), was produced in human cells and purified by means of a
Strep
tag. gH/gL and gB were each able to physically interact with TLR2 in coimmunoprecipitation assays, one independently of the other, yet gH
t-st
/gL, but not gB
730t-st
, elicited an NF-κB response. Thus, whereas both HSV gH/gL and gB are ligands to TLR2, only gH/gL is sufficient to initiate a signaling cascade which leads to NF-κB activation.
Replication-Uncoupled Histone Deposition during Adenovirus DNA Replication
Authors: Komatsu Tetsuro , Nagata Kyosuke
Published: April 2012

In infected cells, the chromatin structure of the adenovirus genome DNA plays critical roles in its genome functions. Previously, we reported that in early phases of infection, incoming viral DNA is associated with both viral core protein VII and cellular histones. Here we show that in late phases of infection, newly synthesized viral DNA is also associated with histones. We also found that the knockdown of CAF-1, a histone chaperone that functions in the replication-coupled deposition of histones, does not affect the level of histone H3 bound on viral chromatin, although CAF-1 is accumulated at viral DNA replication foci together with PCNA. Chromatin immunoprecipitation assays using epitope-tagged histone H3 demonstrated that histone variant H3.3, which is deposited onto the cellular genome in a replication-independent manner, is selectively associated with both incoming and newly synthesized viral DNAs. Microscopic analyses indicated that histones but not USF1, a transcription factor that regulates viral late gene expression, are excluded from viral DNA replication foci and that this is achieved by the oligomerization of the DNA binding protein (DBP). Taken together, these results suggest that histone deposition onto newly synthesized viral DNA is most likely uncoupled with viral DNA replication, and a possible role of DBP oligomerization in this replication-uncoupled histone deposition is discussed.
Structure of Hepatitis C Virus Polymerase in Complex with Primer-Template RNA
Authors: Mosley Ralph T. , Edwards Thomas E. , Murakami Eisuke , Lam Angela M. , Grice Rena L. , Du Jinfa , Sofia Michael J. , Furman Philip A. , Otto Michael J.
Published: April 2012

The replication of the hepatitis C viral (HCV) genome is accomplished by the NS5B RNA-dependent RNA polymerase (RdRp), for which mechanistic understanding and structure-guided drug design efforts have been hampered by its propensity to crystallize in a closed, polymerization-incompetent state. The removal of an autoinhibitory β-hairpin loop from genotype 2a HCV NS5B increases
de novo
RNA synthesis by >100-fold, promotes RNA binding, and facilitated the determination of the first crystallographic structures of HCV polymerase in complex with RNA primer-template pairs. These crystal structures demonstrate the structural realignment required for primer-template recognition and elongation, provide new insights into HCV RNA synthesis at the molecular level, and may prove useful in the structure-based design of novel antiviral compounds. Additionally, our approach for obtaining the RNA primer-template-bound structure of HCV polymerase may be generally applicable to solving RNA-bound complexes for other viral RdRps that contain similar regulatory β-hairpin loops, including bovine viral diarrhea virus, dengue virus, and West Nile virus.
Deletion of U
L
21 Causes a Delay in the Early Stages of the Herpes Simplex Virus 1 Replication Cycle
Authors: Mbong Ekaette F. , Woodley Lucille , Frost Elizabeth , Baines Joel D. , Duffy Carol
Published: April 2012

The herpes simplex virus 1 (HSV-1) U
L
21 gene encodes a 62-kDa tegument protein with homologs in the alpha-, beta-, and gammaherpesvirus subfamilies. In the present study, we characterized a novel U
L
21-null virus and its genetic repair to determine whether this protein plays a role in early stages of the HSV-1 replication cycle. Single-step growth analyses, protein synthesis time courses, and mRNA quantifications indicated that the absence of U
L
21 results in a delay early in the HSV-1 replication cycle.
The N Terminus and C Terminus of Herpes Simplex Virus 1 ICP4 Cooperate To Activate Viral Gene Expression
Authors: Wagner Lauren M. , Lester Jonathan T. , Sivrich Frances L. , DeLuca Neal A.
Published: April 2012

Infected cell polypeptide 4 (ICP4) activates transcription from most viral promoters. Two transactivation domains, one N-terminal and one C terminal, are largely responsible for the activation functions of ICP4. A mutant ICP4 molecule lacking the C-terminal activation domain (n208) efficiently activates many early genes, whereas late genes are poorly activated, and virus growth is severely impaired. The regions within the N terminus of ICP4 (amino acids 1 to 210) that contribute to activation were investigated by analysis of deletion mutants in the presence or absence of the C-terminal activation domain. The mutants were assessed for their abilities to support viral replication and to regulate gene expression. Several deletions in regions conserved in other alphaherpesviruses resulted in impaired activation and viral growth, without affecting DNA binding. The single small deletion that had the greatest effect on activation in the absence of the C terminus corresponded to a highly conserved stretch of amino acids between 81 and 96, rendering the molecule nonfunctional. However, when the C terminus was present, the same deletion had a minimal effect on activity. The amino terminus of ICP4 was predicted to be relatively disordered compared to the DNA-binding domain and the C-terminal 500 amino acids. Moreover, the amino terminus appears to be in a relatively extended conformation as determined by the hydrodynamic properties of several mutants. The data support a model where the amino terminus is an extended and possibly flexible region of the protein, allowing it to efficiently interact with multiple transcription factors at a distance from where it is bound to DNA, thereby enabling ICP4 to function as a general activator of polymerase II transcription. The C terminus of ICP4 can compensate for some of the mutations in the N terminus, suggesting that it either specifies redundant interactions or enables the amino terminus to function more efficiently.
The US16 Gene of Human Cytomegalovirus Is Required for Efficient Viral Infection of Endothelial and Epithelial Cells
Authors: Bronzini Matteo , Luganini Anna , Dell'Oste Valentina , De Andrea Marco , Landolfo Santo , Gribaudo Giorgio
Published: April 2012

The human cytomegalovirus (HCMV) US12 gene family comprises a set of 10 contiguous genes (US12 to US21), each encoding a predicted seven-transmembrane protein and whose specific functions have yet to be ascertained. While inactivation of individual US12 family members in laboratory strains of HCMV has not been found to affect viral replication in fibroblasts, inactivation of US16 was reported to increase replication in microvascular endothelial cells. Here, we investigate the properties of US16 further by ascertaining the expression pattern of its product. A recombinant HCMV encoding a tagged version of the US16 protein expressed a 33-kDa polypeptide that accumulated with late kinetics in the cytoplasmic virion assembly compartment. To elucidate the function(s) of pUS16, we generated US16-deficient mutants in the TR clinical strain of HCMV. According to previous studies, inactivation of US16 had no effect on viral replication in fibroblasts. In contrast, the US16-deficient viruses exhibited a major growth defect in both microvascular endothelial cells and retinal pigment epithelial cells. The expression of representative IE, E, and L viral proteins was impaired in endothelial cells infected with a US16 mutant virus, suggesting a defect in the replication cycle that occurs prior to IE gene expression. This defect must be due to an inefficient entry and/or postentry event, since pp65 and viral DNA did not move to the nucleus in US16 mutant-infected cells. Taken together, these data indicate that the US16 gene encodes a novel virus tropism factor that regulates, in a cell-specific manner, a pre-immediate-early phase of the HCMV replication cycle.
The Epstein-Barr Virus (EBV)-Induced Tumor Suppressor MicroRNA MiR-34a Is Growth Promoting in EBV-Infected B Cells
Authors: Forte Eleonora , Salinas Raul E. , Chang Christina , Zhou Ting , Linnstaedt Sarah D. , Gottwein Eva , Jacobs Cassandra , Jima Dereje , Li Qi-Jing , Dave Sandeep S. , Luftig Micah A.
Published: April 2012

Epstein-Barr virus (EBV) infection of primary human B cells drives their indefinite proliferation into lymphoblastoid cell lines (LCLs). B cell immortalization depends on expression of viral latency genes, as well as the regulation of host genes. Given the important role of microRNAs (miRNAs) in regulating fundamental cellular processes, in this study, we assayed changes in host miRNA expression during primary B cell infection by EBV. We observed and validated dynamic changes in several miRNAs from early proliferation through immortalization; oncogenic miRNAs were induced, and tumor suppressor miRNAs were largely repressed. However, one miRNA described as a p53-targeted tumor suppressor, miR-34a, was strongly induced by EBV infection and expressed in many EBV and Kaposi's sarcoma-associated herpesvirus (KSHV)-infected lymphoma cell lines. EBV latent membrane protein 1 (LMP1) was sufficient to induce miR-34a requiring downstream NF-κB activation but independent of functional p53. Furthermore, overexpression of miR-34a was not toxic in several B lymphoma cell lines, and inhibition of miR-34a impaired the growth of EBV-transformed cells. This study identifies a progrowth role for a tumor-suppressive miRNA in oncogenic-virus-mediated transformation, highlighting the importance of studying miRNA function in different cellular contexts.
Mice Deficient in STAT1 but Not STAT2 or IRF9 Develop a Lethal CD4+T-Cell-Mediated Disease following Infection with Lymphocytic Choriomeningitis Virus
Authors: Hofer Markus J. , Li Wen , Manders Peter , Terry Rachael , Lim Sue Ling , King Nicholas J. C. , Campbell Iain L.
Published: April 2012

Interferon (IFN) signaling is crucial for antiviral immunity. While type I IFN signaling is mediated by STAT1, STAT2, and IRF9, type II IFN signaling requires only STAT1. Here, we studied the roles of these signaling factors in the host response to systemic infection with lymphocytic choriomeningitis virus (LCMV). In wild-type (WT) mice and mice lacking either STAT2 or IRF9, LCMV infection was nonlethal, and the virus either was cleared (WT) or established persistence (STAT2 knockout [KO] and IRF9 KO). However, in the case of STAT1 KO mice, LCMV infection was lethal and accompanied by severe multiorgan immune pathology, elevated expression of various cytokine genes in tissues, and cytokines in the serum. This lethal phenotype was unaltered by the coabsence of the gamma interferon (IFN-γ) receptor and hence was not dependent on IFN-γ. Equally, the disease was not due to a combined defect in type I and type II IFN signaling, as IRF9 KO mice lacking the IFN-γ receptor survived infection with LCMV. Clearance of LCMV is mediated normally by CD8+T cells. However, the depletion of these cells in LCMV-infected STAT1 KO mice was delayed, but did not prevent, lethality. In contrast, depletion of CD4+T cells prevented lethality in LCMV-infected STAT1 KO mice and was associated with a reduction in tissue immune pathology. These studies highlight a fundamental difference in the role of STAT1 versus STAT2 and IRF9. While all three factors are required to limit viral replication and spread, only STAT1 has the unique function of preventing the emergence of a lethal antiviral CD4+T-cell response.
Evaluating bone marrow oedema patterns in musculoskeletal injury
Authors: Kozoriz Michael Gregory , Grebenyuk Julia , Andrews Gordon , Forster Bruce B
Published: April 2012

MRI is a common tool in the evaluation of musculoskeletal injury that allows the clinician to pinpoint specific pathologies. The patient's history and physical exam play a critical role in the diagnosis of sports injuries, however, complementary imaging can play an important role in determining the nature and extent of injury. With the widespread use of MRI, attention has focused on the signals generated following injury. In particular, bone marrow oedema (BME) patterns can be used to aid in the diagnosis of musculoskeletal injury. In this pictorial essay, the authors will demonstrate common patterns of BME that accompany a wide range of musculoskeletal injuries. It is expected that by the end of this article, the reader will be able to (1) recognise BME is a phenomenon observed on MRI following sports injury; (2) recognise typical patterns of BME; (3) understand the relationship of oedema to the type of injury and (4) in the presence of oedema, understand other co-existing injuries that ultimately may have an impact on management.
Cancers related to viral agents that have a direct role in carcinogenesis: pathological and diagnostic techniques
Authors: Carbone Antonino , De Paoli Paolo
Published: April 2012

The International Agency for Research on Cancer has recently reassessed the carcinogenicity of the biological agents classified as ‘carcinogenic to humans’. Among the biological agents having a direct role in carcinogenesis, Epstein-Barr virus, Kaposi's sarcoma-associated herpes virus and human papillomavirus contribute to a variety of malignancies worldwide in humans including nasopharyngeal carcinoma, several types of lymphomas, genital tract carcinomas and Kaposi's sarcoma. The authors review the current knowledge on cancers that have been attributed to Epstein-Barr virus, Kaposi's sarcoma-associated herpes virus and human papillomavirus looking at the pathological classification of these cancers and description of the implicated viruses, highlighting a wide range of pathological and virological diagnostic techniques. This review also focuses on the new oncological scenario ahead, once strategies against carcinogenic infectious agents are found to be effective.
Personal, interpersonal and structural challenges to accessing HIV testing, treatment and care services among female sex workers, men who have sex with men and transgenders in Karnataka state, South India
Authors: Beattie Tara S H , Bhattacharjee Parinita , Suresh M , Isac Shajy , Ramesh B M , Moses Stephen
Published: April 2012

Background

Despite high HIV prevalence rates among most-at-risk groups, utilisation of HIV testing, treatment and care services was relatively low in Karnataka prior to 2008. The authors aimed to understand the barriers to and identify potential solutions for improving HIV service utilisation.

Methods

Focus group discussions were carried out among homogeneous groups of female sex workers, men who have sex with men and transgenders, and programme peer educators in six districts across Karnataka in March and April 2008.

Results

26 focus group discussions were conducted, involving 302 participants. Participants had good knowledge about HIV and HIV voluntary counselling and testing (VCT) services, but awareness of other HIV services was low. The fear of the psychological impact of a positive HIV test result and the perceived repercussions of being seen accessing HIV services were key personal and interpersonal barriers to HIV service utilisation. Previous experiences of discrimination at government healthcare services, coupled with discriminatory attitudes and behaviours by VCT staff, were key structural barriers to VCT service uptake among those who had not been HIV tested. Among those who had used government-managed prevention of parent to child transmission and antiretroviral treatment services, poor physical facilities, long waiting times, lack of available treatment, the need to give bribes to receive care and discriminatory attitudes of healthcare staff presented additional structural barriers.

Conclusions

Embedding some HIV care services within existing programmes for vulnerable populations, as well as improving service quality at government facilities, are suggested to help overcome the multiple barriers to service utilisation. Increasing the uptake of HIV testing, treatment and care services is key to improving the quality and longevity of the lives of HIV-infected individuals.
Community advocacy groups as a means to address the social environment of female sex workers: a case study in Andhra Pradesh, India
Authors: Punyam Swarup , Pullikalu Renuka Somanatha , Mishra Ram Manohar , Sandri Prashanth , Mutupuru Balakrishna Prasad , Kokku Suresh Babu , Parimi Prabhakar
Published: April 2012

Background

To examine the association between the presence of community advocacy groups (CAGs) and female sex workers' (FSWs) access to social entitlements and outcomes of police advocacy.

Methods

Data were used from a cross-sectional survey conducted in 2010–2011 among 1986 FSWs and 104 NGO outreach workers from five districts of Andhra Pradesh. FSWs were recruited using a probability-based sampling from 104 primary sampling units (PSUs). A PSU is a geographical area covered by one outreach worker and is expected to have an active CAG as per community mobilisation efforts. The presence of active CAGs was defined as the presence of an active committee or advocacy group in the area (PSU). Outcome indicators included acquisition of different social entitlements and measures of police response as reported by FSWs. Multivariate linear and logistic regression analyses were used to examine the associations.

Results

Areas with active CAGs compared with their counterparts had a significantly higher mean number of FSWs linked to ration cards (12.8 vs 6.8; p<0.01), bank accounts (9.3 vs 5.9; p=0.05) and health insurance (13.1 vs 7.0; p=0.02). A significantly higher percentage of FSWs from areas with active CAGs as compared with others reported that the police treat them more fairly now than a year before (79.7% vs 70.3%; p<0.05) and the police explained the reasons for arrest when arrested the last time (95.7% vs 87%; p<0.05).

Conclusion

FSWs from areas with active CAGs were more likely to access certain social entitlements and to receive a fair response from the police, highlighting the contributions of CAGs in community mobilisation.
ANTISYMMETRIC TENSOR UNPARTICLE AND THE RADIATIVE LEPTON FLAVOR VIOLATING DECAYS
Authors: ILTAN E. O.
Published: April 2012

We study the contribution of the antisymmetric tensor unparticle mediation to the branching ratios of the radiative lepton flavor violating decays and predict a restriction region for free parameters of the scenario by using experimental upper limits. We observe that the branching ratios of the radiative lepton flavor violating decays are sensitive to the fundamental mass scales of the scenario and to the scale dimension of antisymmetric tensor unparticle. We obtain a more restricted set for the free parameters in the case of the μ→e γ decay.
INFLUENCES OF MAGNETIC FIELD ON MACROSCOPIC PROPERTIES OF WATER
Authors: PANG XIAO-FENG , DENG BO , TANG BO
Published: April 2012

The influences of magnetic field on thermodynamic, mechanical and electromagnetic properties of water including the specific heat, surface tension force, soaking effect or angle of contact, refraction index and electric conductivity are studied. From these investigations we know that the magnetic fields reduce the specific heat of water, increase the soaking degree and hydrophobicity of water to materials, depress its surface tension force and increase refractive index and electric conductivity of water relative to those of pure water. We can predict that these changes are caused by the changes of microscopic structures and distribution of water molecules under the action of a magnetic field. Therefore, our studies have important significations in science and has practical value of application of magnetized water.
NOVEL ACCELERATING EINSTEIN VACUA AND SMOOTH INHOMOGENEOUS RIEMANNIAN MANIFOLDS
Authors: MENG KUN , XU WEI , ZHAO LIU
Published: April 2012

A novel class of Einstein vacua is presented, which possess nonvanishing cosmological constant and accelerating horizon with the topology of SD-3 fibration over S1. After Euclideanization, the solution describes a conformally distorted SD-1 fibration over S1, which is smooth, compact and inhomogeneous and can be regarded as analog of Don Page's gravitational instanton.
HARD GAMMA-RAY SOURCE SPECTRA IN TeV BLAZARS
Authors: LEFA EVA , RIEGER FRANK M. , AHARONIAN FELIX A.
Published: April 2012

The problem of the hard (intrinsic) γ-ray source spectra in TeV blazars is examined. We show that relativistic Maxwell-like particle distributions provide a suitable interpretation for the inferred hard, very high energy (VHE) photon spectra. We discuss the potential of these distributions to produce broader and softer spectra if multiple zones contribute to the observed emission. We show that the dominance of one component could lead to a VHE flaring state with hard spectral features, like the one observed for Mkn 501 in July 2009.
EXPECTED GAMMA-RAY EMISSION FROM X-RAY BINARIES
Authors: BEDNAREK WŁODEK
Published: April 2012

It is at present well known that conditions at some massive binary systems allow acceleration of particles and production of the GeV-TeV γ-rays. However, which particles are responsible for this emission and what radiation processes are engaged is at present not completely clear. We discuss what parameters can determine the acceleration process of particles and high energy radiation produced by them within massive binary systems.
RESULTS FROM THE BINARIES LS I +61°303 and LS 5039 AFTER 2.5 YEARS OF FERMI MONITORING
Authors:   On behalf of the Fermi-LAT collaboration, HADASCH DANIELA
Published: April 2012

The Fermi Large Area Telescope (LAT) made the first definitive GeV detections of the binaries LS I +61°303 and LS 5039 in the first year after its launch in August 2008. These detections were unambiguous because, apart from a reduced positional uncertainty, the γ-ray emission in each case was orbitally modulated with the corresponding orbital period. The LAT results posed new questions about the nature of these objects, after the unexpected observation of an exponential cutoff in the GeV γ-ray spectra of both LS I +61°303 and LS 5039, at least along part of their orbital motion. We present here the analysis of new data from the LAT, comprising 2.5 years of observations through which LS I +61°303 continues to provide some surprises. We find an increase in flux in March 2009 and a steady decrease in the flux fraction modulation. The LAT now detects emission up to 30 GeV, where prior datasets led to upper limits only. At the same time, contemporaneous TeV observations either no longer detected the source, or found it -at least in some orbits- close to periastron, far from the usual phases in which the source usually appeared at TeV energies. The on-source exposure of LS 5039 has also drastically increased along the last years, and whilst our analysis shows no new behavior in comparison with our earlier report, the higher statistics of the current dataset allows for a deeper investigation of its orbital and spectral evolution.
THERMAL BALANCE OF THE JET IN THE MICROQUASAR SS433
Authors: BISNOVATYI-KOGAN G. S. , KRIVOSHEYEV YU. M.
Published: April 2012

Thermal balance of the jet in the source SS433 is considered accounting for radiative and adiabatic cooling, and different heating mechanisms. We consider jet heating by the Compton effect of coronal hard X-ray photons on jet electrons, the influence of shock wave propagation along the jet, and jet kinetic energy transformation into heat via Coulomb collisions of jet and corona protons. The most important heating mechanism for the source SS433 turns out to be Coulomb collisions of jet particles with the surrounding medium.
VLBI STRUCTURE OF PSR B1259-63/LS 2883 DURING THE 2007 AND 2010 PERIASTORN PASSAGES
Authors: MOLDÓN J. , RIBÓ M. , PAREDES J. M. , JOHNSTON S. , DELLER A. T.
Published: April 2012

PSR B1259-63 is a 48 ms pulsar in a highly eccentric 3.4-year orbit around the young massive star LS 2883. During the periastron passage the system displays transient non-thermal unpulsed emission from radio to very high energy gamma rays. We observed PSR B1259-63 with the Australian Long Baseline Array (LBA) at 2.3 GHz to trace the milliarcsecond (mas) structure of the source at three different epochs during the 2007 periastron passage. We have discovered extended and variable radio structure. The peak of the radio emission is detected at distances between 23 and 46 AU from the system assuming a distance to the system of 2.3 kpc, and the total extent of the emission is 120 AU. This is the first observational evidence that non-accreting pulsars orbiting massive stars can produce variable extended radio emission at AU scales. We also present the new LBA campaign covering five different orbital phases during the 2010–2011 periastron passage. These observations will allow us to separate the pulsed radio component from the transient extended emission.
PHYSICAL PROPERTIES OF JETS IN AGN
Authors: HOMAN DANIEL C.
Published: April 2012

I review constraints on the physical properties of AGN jets revealed through Very Long Baseline Interferometry (VLBI) studies of the structure and time-evolution of parsec-scale jets, including recent results from the MOJAVE program. In particular I focus on constraints available from very long time baseline studies which probe a wide range of jet behavior over many outbursts. Kinematic studies of propagating jet features find an apparent speed distribution that peaks around 10c for blazars, with speeds up to 50c observed. These observed speeds require Lorentz factors at least as large, implying that parsec-scale Lorentz factors up to 10-20 are common for blazars with a tail up to ~ 50. Jet flows are still becoming organized on these scales as evidenced by the high incidence of non-radial motions and/or accelerations of jet features (including increases and decreases in apparent speed and direction). Changes in Lorentz factors of propagating jet features appear to play a significant role in the observed accelerations, and while the connection between acceleration of jet features and the underlying flow is not clear, the pattern of observed accelerations suggest the flow may increase in speed near the base of the jet and decrease further out. In some jets, ejections of new features span a range of ejection angles over many epochs, tracing out wider opening angles on parsec-scales than are apparent in single epoch observations.
PHOTOSPHERIC THERMAL RADIATION FROM GRB COLLAPSAR JETS
Authors: MIZUTA AKIRA , NAGATAKI SHIGEHIRO
Published: April 2012

We have performed 2D relativistic hydrodynamic simulations of jets from a collapsar. The light curves and spectrum of the photospheric thermal radiation from ultrarelativistic gamma-ray burst (GRB) jets are calculated by the post process. At the head the jet has a dissipated region in which internal shocks can be seen and a freely expanding region follows. The freely expanding region shows a bullet like shape. The light curves continue about 100 s which corresponds to the jet injection duration. The light curves for θv ≤ 2° show quick rise and time variability for the first phase and low and steady luminosity phase follows. The light curves for θv ≥ 3° show slow rise and low luminosity. The spectrum below the peak energy is a power law and the index is 1 ~ 2.6 which is softer than that of single temperature plank distribution Some of them are close to the observed one, i.e., Band function.
JET STABILITY, DYNAMICS AND ENERGY TRANSPORT
Authors: PERUCHO MANEL
Published: April 2012

Relativistic jets carry energy and particles from compact to very large scales compared with their initial radius. This is possible due to their remarkable collimation despite their intrinsic unstable nature. In this contribution, I review the state-of-the-art of our knowledge on instabilities growing in those jets and several stabilising mechanisms that may give an answer to the question of the stability of jets. In particular, during the last years we have learned that the limit imposed by the speed of light sets a maximum amplitude to the instabilities, contrary to the case of classical jets. On top of this stabilising mechanism, the fast growth of unstable modes with small wavelengths prevents the total disruption and entrainment of jets. I also review several non-linear processes that can have an effect on the collimation of extragalactic and microquasar jets. Within those, I remark possible causes for the decollimation and deceleration of FRI jets, as opposed to the collimated FRII's. Finally, I give a summary of the main reasons why jets can propagate through such long distances.
JETS FROM STELLAR TIDAL DISRUPTIONS BY SUPERMASSIVE BLACK HOLES
Authors: GIANNIOS DIMITRIOS , METZGER BRIAN D.
Published: April 2012

The tidal disruption of a star by a supermassive black hole provides us with unique information for otherwise dormant galactic nuclei. It has long been predicted that the disruption will be accompanied by a thermal 'flare', powered by the accretion of stellar debris. Recently, we proposed that a modest fraction of the accretion power can be channeled into a relativistic jet. We showed that, even if the jet is not pointing at our direction, the interactions of the jet with the interstellar medium can power a bright radio-IR transient. Recent transients discovered by Swift have all the expected characteristics of a new-born jet powered by the tidal disruption of a star. The evidence is strong that we are witnessing a most direct verification of the our proposal with the transient jet pointing directly at us. Upcoming radio transient surveys can independently discover numerous disruptions, complimenting searches at other wavelengths. Tidal disruptions can probe the physics of jet formation under relatively clean conditions, in which the flow parameters are independently constrained.
HELICAL MAGNETIC FIELDS IN RELATIVISTIC JETS THROUGH FARADAY ROTATION AND JET STRATIFICATION STUDIES
Authors: GÓMEZ JOSÉ L. , CASADIO CAROLINA , ROCA-SOGORB MAR , AGUDO IVÁN , MARSCHER ALAN P. , JORSTAD SVETLANA G.
Published: April 2012

Helical magnetic fields may play an important role in the formation, collimation, and acceleration of relativistic jets in active galactic nuclei. These may be searched for by looking for Faraday rotation measure (RM) gradients and emission stratification across the jet width. Multi-epoch polarimetric Very Long Baseline Array (VLBA) observations of the radio galaxy 3C 120 have revealed the existence of such a RM gradient across the jet, but the presence of a localized region of enhanced RM and uncorrelated changes in the polarization of the underlying jet emission and the Faraday rotation screen suggest that a significant fraction of the RM found in 3C 120 originates in foreground clouds. Thanks to the combination of 48 images spanning 14 years of 15 GHz VLBA observations of 3C 273 we have found a stratification in total intensity across the jet that flips sides with distance along the jet, supporting a model in which the jet of 3C 273 accelerates and is threaded by a helical magnetic field.
MAPCAT: MONITORING AGN WITH POLARIMETRY AT THE CALAR ALTO TELESCOPES
Authors: AGUDO IVÁN , MOLINA SOL N. , GÓMEZ JOSÉ L. , MARSCHER ALAN P. , JORSTAD SVETLANA G. , HEIDT JOCHEN
Published: April 2012

We introduce MAPCAT, a long-term observing program for "Monitoring of AGN with Polarimetry at the Calar Alto Telescopes". Multi-spectral-range studies are critical to understand some of the most relevant current problems of high energy astrophysics of blazars such as their high energy emission mechanisms and the location of their γ-ray emission region through event associations across the spectrum. Adding multi-spectral-range polarimetry allows for even more reliable identification of polarized flares across the spectrum in these kind of objects, as well as for more accurate modeling of their magnetic field. As part of a major international effort to study the long term multi-spectral range polarimetric behavior of blazars, MAPCAT uses -since mid 2007- CAFOS on the 2.2m Telescope at the Calar Alto Observatory (Almería, Spain) to obtain monthly optical (R-band) photo-polarimetric measurements of a sample of 34 of the brightest γ-ray, optical, and radio-millimeter blazars accessible from the northern hemisphere.
BL LAC POPULATION STUDY: EARLY RESULTS USING THE Fermi 11-MONTH CATALOG
Authors: GÉRARD LUCIE , PITA SANTIAGO , PUNCH MICHAEL , HENRI GILLES
Published: April 2012

In the framework of AGN unification, BL Lacs and their parent population would share the same intrinsic characteristics, the observational differences being due to the orientation of the jet compared to our line of sight. BL Lacs would be those objects whose jet is oriented towards us, Doppler boosting the emission. The growing number of BL Lacs detected at HE (> 100 MeV) and VHE (> 100 GeV) is a challenge for this scheme, since the high values of Doppler factors needed to explain the emission of these sources imply a large density for the parent population.

We studied the BL Lac source sample detected by Fermi after 11 months of observation. Using the data presented in Fermi's first AGN catalog, we put constraints on the intrinsic characteristics of this BL Lac population, such as the intrinsic luminosity and Lorentz factor distributions. Based on these results, we used Monte Carlo simulations to constrain the space density of the parent population and the jet opening angle.
VLBI OBSERVATIONS OF THE SHORTEST ORBITAL PERIOD BLACK HOLE X-RAY BINARY
Authors: PARAGI ZSOLT , BELLONI TOMASO M. , VAN DER HORST ALEXANDER J. , MILLER-JONES JAMES
Published: April 2012

The X-ray transient MAXI J1659-152 was discovered by Swift/BAT and it was initially identified as a GRB. Soon its Galactic origin and binary nature were established. There exists a wealth of multi-wavelength monitoring data for this source, providing a great coverage of the full X-ray transition in this candidate black hole binary system. We obtained two epochs of EVN/e-VLBI and four epochs of VLBA data of MAXI J1659-152 which show evidence for some extended emission in the early phases but –against expectations– no major collimated ejecta during the accretion disk state transition. This might be related to the fact that, with a red dwarf donor star, MAXI J1659-152 is the shortest orbital period black hole X-ray binary system.
Hsp90 regulates O-linked β-N-acetylglucosamine transferase: a novel mechanism of modulation of protein O-linked β-N-acetylglucosamine modification in endothelial cells
Authors: Zhang Fengxue , Snead Connie M. , Catravas John D.
Published: April 2012

O-linked β- N-acetylglucosamine (O-GlcNAc) modification of proteins is involved in many important cellular processes. Increased O-GlcNAc has been implicated in major diseases, such as diabetes and its complications and cardiovascular and neurodegenerative diseases. Recently, we reported that O-GlcNAc modification occurs in the proteasome and serves to inhibit proteasome function by blocking the ATPase activity in the 19S regulatory cap, explaining, at least in part, the adverse effects of O-GlcNAc modification and suggesting that downregulating O-GlcNAc might be important in the treatment of human diseases. In this study, we report on a novel mechanism to modulate cellular O-GlcNAc modification, namely through heat shock protein 90 (Hsp90) inhibition. We observed that O-linked β- N-acetylglucosamine transferase (OGT) interacts with the tetratricopeptide repeat binding site of Hsp90. Inhibition of Hsp90 by its specific inhibitors, radicicol or 17- N-allylamino-17-demethoxygeldanamycin, destabilized OGT in primary endothelial cell cultures and enhanced its degradation by the proteasome. Furthermore, Hsp90 inhibition downregulated O-GlcNAc protein modifications and attenuated the high glucose-induced increase in O-GlcNAc protein modification, including high glucose-induced increase in endothelial or type 3 isoform of nitric oxide synthase (eNOS) O-GlcNAcylation. These results suggest that Hsp90 is involved in the regulation of OGT and O-GlcNAc modification and that Hsp90 inhibitors might be used to modulate O-GlcNAc modification and reverse its adverse effects in human diseases.