bluuebunny/crossref_metadata_2025_split huggingface dataset:
Escherichia coli phage‐shock protein A (PspA) binds to membrane phospholipids and repairs proton leakage of the damaged membranes
Authors: Kobayashi Ryuji , Suzuki Toshiharu , Yoshida Masasuke 
Published: September 2007

Summary Escherichia coli phage‐shock protein A (PspA), a 25.3 kDa peripheral membrane protein, is induced under the membrane stress conditions and is assumed to help maintain membrane potential. Here, we report that purified PspA, existing as a large oligomer, is really able to suppress proton leakage of the membranes. This was demonstrated for membrane vesicles prepared from the PspA‐lacking E. coli mutants, and for membrane vesicles damaged by ethanol and Triton X‐100 prepared from the mutant and the wild‐type cells. PspA also suppressed proton leakage of damaged liposomes made from E. coli total lipids. Furthermore, we found that PspA bound preferentially to liposomes containing phosphatidylserine and phosphatidylglycerol. All these effects were not observed for monomer PspA that was prepared by refolding of urea‐denatured PspA. These results indicate that oligomers of PspA bind to membrane phospholipids and suppress proton leakage.
Transcriptional control of nmrA by the bZIP transcription factor MeaB reveals a new level of nitrogen regulation in Aspergillus nidulans
Authors: Wong Koon Ho , Hynes Michael J. , Todd Richard B. , Davis Meryl A. 
Published: September 2007

SummaryFungi can use a diverse range of nitrogen sources. Some nitrogen sources sustain a rapid growth rate and are used in preference to less readily metabolized nitrogen sources. The mechanisms involved in this control of nitrogen utilization have been studied in the model filamentous ascomycete, Aspergillus nidulans. The GATA transcription factor AreA is necessary for the expression of nitrogen‐catabolic permeases and enzymes. AreA activity is controlled by multiple mechanisms including regulated areA transcript levels and regulated AreA nuclear export. During nitrogen sufficiency, AreA activation is also prevented by the co‐repressor NmrA. We have investigated nitrogen signalling to NmrA. NmrA overexpression prevents AreA function irrespective of the nitrogen status. The mRNA levels of areA and nmrA are inversely regulated, suggesting that the relative levels of AreA and NmrA are critical in determining AreA activation. The bZIP transcription factor MeaB was found to activate nmrA expression and a conserved element, TTGCACCAT, bound by MeaB in vitro is present in the promoters of NmrA homologues in other filamentous ascomycetes. Expression of meaB was not strongly regulated suggesting that transcriptional activation by MeaB is modulated by the nitrogen status. This work highlights a new level of complexity in the regulation of nitrogen catabolism.
Factors shaping genetic variation in the MHC of natural non‐human primate populations
Authors: Bonhomme M. , Blancher A. , Jalil M. F. , Crouau‐Roy B. 
Published: September 2007

AbstractAcross a large distribution range, population‐specific factors as well as pathogen‐mediated selection may shape species genetic diversity in the major histocompatibility complex (MHC). We have studied genetic diversity and population differentiation in the MHC region of the Southeast Asian cynomolgus macaque (Macaca fascicularis fascicularis), a species with large and discontinuous range, in order to investigate the role of demography vs selection. Genetic variation was assessed at seven MHC microsatellites on 272 individuals from five populations (Indochina, Java, Borneo, Philippines, and Mauritius). A high genetic diversity was observed in all populations and the Philippines but also the Mauritius populations were the most genetically differentiated. The strength and extent of linkage disequilibrium (LD) (up to 4 Mb) varies across populations mainly because of demographic factors. In Indochina, the complete lack of LD could be the signature of ancient hybridization between cynomolgus and rhesus macaques in the Indochinese peninsula. With the additional support of seven autosomal microsatellites, tests for outlier loci based on intrapopulation diversity and interpopulation differentiation (using F‐statistic) allowed to dissociate demographic from selective histories: (i) demographic history may itself explain levels of MHC variability in the Mauritius populations and (ii) positive selection could be responsible for the Philippines population differentiation, especially in the MHC class II region. Among various pathogens, Plasmodium knowlesi and Plasmodium coatneyi are two likely candidates to explain the higher frequency of some MHC haplotypes. Indeed, literature describes low parasitemia in the Philippines individuals, contrasting with fatal infections provoked by these parasites in other cynomolgus macaque populations.
Dissociation of sad facial expressions and autonomic nervous system responding in boys with disruptive behavior disorders
Authors: Marsh Penny , Beauchaine Theodore P. , Williams Bailey 
Published: September 2007

AbstractAlthough deficiencies in emotional responding have been linked to externalizing behaviors in children, little is known about how discrete response systems (e.g., expressive, physiological) are coordinated during emotional challenge among these youth. We examined time‐linked correspondence of sad facial expressions and autonomic reactivity during an empathy‐eliciting task among boys with disruptive behavior disorders (n=31) and controls (n=23). For controls, sad facial expressions were associated with reduced sympathetic (lower skin conductance level, lengthened cardiac preejection period [PEP]) and increased parasympathetic (higher respiratory sinus arrhythmia [RSA]) activity. In contrast, no correspondence between facial expressions and autonomic reactivity was observed among boys with conduct problems. Furthermore, low correspondence between facial expressions and PEP predicted externalizing symptom severity, whereas low correspondence between facial expressions and RSA predicted internalizing symptom severity.
The burden of caesarean section refusal in a developing country setting
Authors: Chigbu CO , Iloabachie GC 
Published: September 2007

Objective  To investigate the prevalence, aetiology and outcomes of caesarean section refusal in pregnant women.Design  A prospective controlled study.Setting  University of Nigeria Teaching Hospital and Aghaeze Hospital, Enugu, Nigeria.Population  A total of 62 Nigerian women who declined elective caesarean section.Method  Interviewer‐administered questionnaires at the time of caesarean section refusal and postdelivery. The delivery outcomes of the subjects were compared with that of a matched control group of women who accepted caesarean section.Main outcome measures  Prevalence, maternal reasons for caesarean section refusal and the resultant maternal and perinatal mortality.Results  The prevalence of caesarean section refusal was 11.6% of all caesarean deliveries. Maternal reasons for refusing caesarean section include fear of death, economic reasons, desire to experience vaginal delivery and inadequate counselling. Outcomes were significantly worse among women who refused elective caesarean section than in the controls with a maternal mortality of 15% (versus 2%, P = 0.008) and a perinatal mortality of 34% (versus 5%, P < 0.001).Conclusion  There is a high prevalence of caesarean section refusal in south‐eastern Nigeria. Women declining caesareans have very poor maternal and perinatal outcomes and need extra support.
Urological and colorectal complications following surgery for rectovaginal endometriosis
Authors: Slack A , Child T , Lindsey I , Kennedy S , Cunningham C , Mortensen N , Koninckx P , McVeigh E 
Published: September 2007

Objectives  To report the short‐ and medium‐term complications of laparoscopic laser excisional surgery for rectovaginal endometriosis.Design  Retrospective cohort study.Setting  University teaching hospital, UK.Population  A total of 128 women with histologically confirmed rectovaginal endometriosis who underwent laparoscopic laser surgery between May 1999 and September 2006.Methods  Women were identified from operative database, and a case note review was performed. Data for surgical outcome and surgical complications were collected.Main outcome measures  Rates of urinary tract and colorectal complications.Results  A total of 128 women underwent surgery. Of these, 32 required intraoperative closure of a rectal wall defect, including 3 segmental rectosigmoid resections. There were three rectovaginal fistulae and one ureterovaginal fistula. Ureteric damage occurred in two women, and five women suffered postoperative urinary retention. The risk of intraoperative bowel intervention was increased in women who complained of cyclical rectal bleeding.Conclusion  Laparoscopic laser excision of rectovaginal endometriosis is a safe procedure with similar, if not lower, complication rates to other published surgical series.
Squamous cell carcinoma arising in a dermoid cyst of the ovary: a case series
Authors: Hurwitz JL , Fenton A , McCluggage WG , McKenna S 
Published: September 2007

Objective  Malignant transformation in a dermoid cyst of the ovary is a rare complication, occurring in only 1–2% of cases, with squamous cell carcinoma being the most common type. Preoperative diagnosis is difficult because of the lack of specific symptoms and signs to suggest malignancy. Because of the small numbers of women involved, our knowledge of this rare tumour type is limited. This study aims to further characterise the population of women affected, the disease itself and the most appropriate management strategy.Design  We identified 14 women with this diagnosis between 1989 and 2006. This is a descriptive study, looking at the patient characteristics, mode of presentation and the role of tumour markers and radiological imaging in diagnosis. We also examined the stage and pathological features of the tumour at presentation and the subsequent course of the disease. We have also described our experiences using surgery, chemotherapy and radiotherapy in the management of these women.Results  We found that these tumours present at an age older than that of mature teratomas and that there are no reliable diagnostic tools or prognostic indicators. The behaviour of these tumours is unpredictable, and the role of chemotherapy and radiotherapy remains unclear. We suggest that repeated surgical resection of disease at the time of relapse could give a very durable response in selected women.
Larvicidal efficacy of Aloe barbadensis and Cannabis sativa against the malaria vector Anopheles stephensi (Diptera: Culicidae)
Authors: MAURYA Prejwltta , MOHAN Lalit , SHARMA Preeti , BATABYAL Lata , SRIVASTAVA C. N. 
Published: September 2007

Abstract Anopheles stephensi is the primary vector of malaria, an endemic disease in India. An effort to control An. stephensi larvae by leaf extracts of Aloe barbadensis (Liliaceae) and Cannabis sativa (Moraceae) was made under laboratory conditions. A carbon tetrachloride extract of A. barbadensis was the most effective of all the extracts tested for larvicidal activity against the anopheline larvae, with LC50 15.58 and 8.04 p.p.m. after 24 and 48 h of exposure, respectively. Thus, the leaf extract of A. barbadensis has active components that could be useful as a larvicide of ecocongenial nature against malaria vectors.
Clinical, laboratory and therapeutic aspects of platelet‐type von Willebrand disease
Authors: FRANCHINI M. , MONTAGNANA M. , LIPPI G. 
Published: September 2007

SummaryPlatelet‐type von Willebrand disease (PT‐VWD), or pseudo‐VWD, is a rare inherited platelet disorder characterized by an increased affinity of the platelet membrane glycoprotein Ibα receptor for normal von Willebrand factor leading to characteristic platelet hyperaggregability. As PT‐VWD shares most of the clinical and laboratory features of subtype 2B VWD, the differential diagnosis between these two inherited bleeding disorders requires either platelet‐mixing or molecular genetic studies. In this review, the main clinical, laboratory and therapeutic characteristics of PT‐VWD are concisely reported.
The Flagellar Muramidase from the Photosynthetic Bacterium
Rhodobacter sphaeroides
Authors: de la Mora Javier , Ballado Teresa , González-Pedrajo Bertha , Camarena Laura , Dreyfus Georges 
Published: September 2007

ABSTRACT

We have characterized open reading frame RSP0072, which is located within the
flgG
operon in
Rhodobacter sphaeroides
. The amino acid sequence analysis of this gene product showed the presence of a soluble lytic transglycosylase domain. The deletion of the N-terminal region (90 amino acids) of the product of RSP0072 yields a leaky nonmotile phenotype, as determined by swarm assays in soft agar. Electron micrographs revealed the lack of flagella in mutant cells. The purified wild-type protein showed lytic activity on extracts of
Micrococcus luteus
. In contrast, no lytic activity was observed when the residues E57 or E83 were replaced by alanine. Affinity blotting suggests that the protein encoded by RSP0072 interacts with the flagellar rod-scaffolding protein FlgJ, which lacks the muramidase domain present in FlgJ of many bacteria. We propose that the product of RSP0072 is a flagellar muramidase that is exported to the periplasm via the Sec pathway, where it interacts with FlgJ to open a gap in the peptidoglycan layer for the subsequent penetration of the nascent flagellar structure.
Effect of Viral Load on the Outcome of Herpes Zoster
Authors: Quinlivan M. L. , Ayres K. , Ran H. , McElwaine S. , Leedham-Green M. , Scott F. T. , Johnson R. W. , Breuer J. 
Published: September 2007

ABSTRACT

Varicella-zoster virus (VZV) is a member of the
Herpesviridae
family, primary infection with which causes varicella, more commonly known as chicken pox. Characteristic of members of the alphaherpesvirus subfamily, VZV is neurotropic and establishes latency in sensory neurons. Reactivation of VZV causes herpes zoster, also known as shingles. The most frequent complication following zoster is chronic and often debilitating pain called postherpetic neuralgia (PHN), which can last for months after the disappearance of a rash. During episodes of acute zoster, VZV viremia occurs in some, but not all, patients; however, the effect of the viral load on the disease outcome is not known. Here we describe the development of a highly specific, sensitive, and reproducible real-time PCR assay to investigate the factors that may contribute to the presence and levels of baseline viremia in patients with zoster and to determine the relationship between viremia and the development and persistence of PHN. VZV DNA was detected in the peripheral blood mononuclear cells (PBMCs) of 78% of patients with acute zoster and in 9% of healthy asymptomatic blood donors. The presence of VZV in the PBMCs of patients with acute zoster was independently associated with age and being on antivirals but not with gender, immune status, extent of rash, the age of the rash at the time of blood sampling, having a history of prodromal pain, or the extent of acute pain. Prodromal pain was significantly associated with higher baseline viral loads. Viral load levels were not associated with the development or persistence of PHN at 6, 12, or 26 weeks.
Influenza Virus-Induced Type I Interferon Leads to Polyclonal B-Cell Activation but Does Not Break Down B-Cell Tolerance
Authors: Woods Anne , Monneaux Fanny , Soulas-Sprauel Pauline , Muller Sylviane , Martin Thierry , Korganow Anne-Sophie , Pasquali Jean-Louis 
Published: September 2007

ABSTRACTThe link between infection and autoimmunity is not yet well understood. This study was designed to evaluate if an acute viral infection known to induce type I interferon production, like influenza, can by itself be responsible for the breakdown of immune tolerance and for autoimmunity. We first tested the effects of influenza virus on B cells in vitro. We then infected different transgenic mice expressing human rheumatoid factors (RF) in the absence or in the constitutive presence of the autoantigen (human immunoglobulin G [IgG]) and young lupus-prone mice [(NZB × NZW)F1] with influenza virus and looked for B-cell activation. In vitro, the virus induces B-cell activation through type I interferon production by non-B cells but does not directly stimulate purified B cells. In vivo, both RF and non-RF B cells were activated in an autoantigen-independent manner. This activation was abortive since IgM and IgM-RF production levels were not increased in infected mice compared to uninfected controls, whether or not anti-influenza virus human IgG was detected and even after viral rechallenge. As in RF transgenic mice, acute viral infection of (NZB × NZW)F1mice induced only an abortive activation of B cells and no increase in autoantibody production compared to uninfected animals. Taken together, these experiments show that virus-induced acute type I interferon production is not able by itself to break down B-cell tolerance in both normal and autoimmune genetic backgrounds.
Occurrence of the European Subgroup of Subtype I BK Polyomavirus in Japanese-Americans Suggests Transmission outside the Family
Authors: Yogo Yoshiaki , Zhong Shan , Suzuki Makoto , Shibuya Ayako , Kitamura Tadaichi 
Published: September 2007

ABSTRACT
To examine the mode of transmission of BK polyomavirus (BKV), urine samples were collected from Japanese-Americans in Los Angeles and from other southern Californians. Subtype I was the main subtype found in samples from both groups. The subtype I subgroup Ib-2, which is predominant in Europe, was the primary subgroup detected in second-generation Japanese-Americans and in southern Californians; however, the Ic subgroup prevalent in native Japanese was rare in these populations. Since the European subgroup (Ib-2) predominated in the studied geographic area, the findings demonstrate that transmission outside the family is common in the spread of BKV, unlike previous findings for JC polyomavirus.
Mutations in Envelope gp120 Can Impact Proteolytic Processing of the gp160 Precursor and Thereby Affect Neutralization Sensitivity of Human Immunodeficiency Virus Type 1 Pseudoviruses
Authors: Blay Wendy M. , Kasprzyk Theresa , Misher Lynda , Richardson Barbra A. , Haigwood Nancy L. 
Published: September 2007

ABSTRACT

The design of an efficient human immunodeficiency virus (HIV) immunogen able to generate broad neutralizing antibodies (NAbs) remains an elusive goal. As more data emerge, it is becoming apparent that one important aspect of such an immunogen will be the proper representation of the envelope protein (Env) as it exists on native virions. Important questions that are yet to be fully addressed include what factors dictate Env processing, how different Env forms are represented on the virion, and ultimately how these issues influence the development and efficacy of NAbs. Recent data have begun to illuminate the extent to which changes in gp41 can impact the overall structure and neutralizing sensitivity of Env. Here, we present evidence to suggest that minor mutations in gp120 can significantly impact Env processing. We analyzed the gp120 sequences of 20
env
variants that evolved in multiple macaques over 8 months of infection with simian/human immunodeficiency virus 89.6P. Variant gp120 sequences were subcloned into gp160 expression plasmids with identical cleavage motifs and gp41 sequences. Cells cotransfected with these plasmids and Δ
env
genomes were able to produce competent virus. The resulting pseudoviruses incorporated high levels of Env onto virions that exhibited a range of degrees of virion-associated Env cleavage (15 to 40%). Higher levels of cleavage correlated with increased infectivity and increased resistance to macaque plasma, HIV immunoglobulin, soluble CD4, and human monoclonal antibodies 4E10, 2F5, and b12. Based on these data, we discuss a model whereby changes in gp120 of 89.6P impact Env processing and thereby mediate escape from a range of neutralizing agents.
Suppression of Viremia and Evolution of Human Immunodeficiency Virus Type 1 Drug Resistance in a Macaque Model for Antiretroviral Therapy
Authors: Ambrose Zandrea , Palmer Sarah , Boltz Valerie F. , Kearney Mary , Larsen Kay , Polacino Patricia , Flanary Leon , Oswald Kelli , Piatak Michael , Smedley Jeremy , Shao Wei , Bischofberger Norbert , Maldarelli Frank , Kimata Jason T. , Mellors John W. , Hu Shiu-Lok , Coffin John M. , Lifson Jeffrey D. , KewalRamani Vineet N. 
Published: September 2007

ABSTRACT
Antiretroviral therapy (ART) in human immunodeficiency virus type 1 (HIV-1)-infected patients does not clear the infection and can select for drug resistance over time. Not only is drug-resistant HIV-1 a concern for infected individuals on continual therapy, but it is an emerging problem in resource-limited settings where, in efforts to stem mother-to-child-transmission of HIV-1, transient nonnucleoside reverse transcriptase inhibitor (NNRTI) therapy given during labor can select for NNRTI resistance in both mother and child. Questions of HIV-1 persistence and drug resistance are highly amenable to exploration within animals models, where therapy manipulation is less constrained. We examined a pigtail macaque infection model responsive to anti-HIV-1 therapy to study the development of resistance. Pigtail macaques were infected with a pathogenic simian immunodeficiency virus encoding HIV-1 reverse transcriptase (RT-SHIV) to examine the impact of prior exposure to a NNRTI on subsequent ART comprised of a NNRTI and two nucleoside RT inhibitors. K103N resistance-conferring mutations in RT rapidly accumulated in 2/3 infected animals after NNRTI monotherapy and contributed to virologic failure during ART in 1/3 animals. By contrast, ART effectively suppressed RT-SHIV in 5/6 animals. These data indicate that suboptimal therapy facilitates HIV-1 drug resistance and suggest that this model can be used to investigate persisting viral reservoirs.
Isolation of Avian Paramyxovirus 1 from a Patient with a Lethal Case of Pneumonia
Authors: Goebel Scott J. , Taylor Jill , Barr Bradd C. , Kiehn Timothy E. , Castro-Malaspina Hugo R. , Hedvat Cyrus V. , Rush-Wilson Kim A. , Kelly Cassandra D. , Davis Stephen W. , Samsonoff William A. , Hurst Kelley R. , Behr Melissa J. , Masters Paul S. 
Published: September 2007

ABSTRACT
An unknown virus was isolated from a lung biopsy sample and multiple other samples from a patient who developed a lethal case of pneumonia following a peripheral blood stem cell transplant. A random PCR-based molecular screening method was used to identify the infectious agent as avian paramyxovirus 1 (APMV-1; a group encompassing Newcastle disease virus), which is a highly contagious poultry pathogen that has only rarely been found in human infections. Immunohistochemical analysis confirmed the presence of APMV-1 antigen in sloughed alveolar cells in lung tissue from autopsy. Sequence from the human isolate showed that it was most closely related to virulent pigeon strains of APMV-1. This is the most completely documented case of a systemic human infection caused by APMV-1 and is the first report of an association between this virus and a fatal disease in a human.
DDX3 DEAD-Box RNA Helicase Is Required for Hepatitis C Virus RNA Replication
Authors: Ariumi Yasuo , Kuroki Misao , Abe Ken-ichi , Dansako Hiromichi , Ikeda Masanori , Wakita Takaji , Kato Nobuyuki 
Published: September 2007

ABSTRACT
DDX3, a DEAD-box RNA helicase, binds to the hepatitis C virus (HCV) core protein. However, the role(s) of DDX3 in HCV replication is still not understood. Here we demonstrate that the accumulation of both genome-length HCV RNA (HCV-O, genotype 1b) and its replicon RNA were significantly suppressed in HuH-7-derived cells expressing short hairpin RNA targeted to DDX3 by lentivirus vector transduction. As well, RNA replication of JFH1 (genotype 2a) and release of the core into the culture supernatants were suppressed in DDX3 knockdown cells after inoculation of the cell culture-generated HCVcc. Thus, DDX3 is required for HCV RNA replication.