bluuebunny/crossref_metadata_2025_split huggingface dataset:
De Novo
Guanine Biosynthesis but Not the Riboswitch-Regulated Purine Salvage Pathway Is Required for Staphylococcus aureus Infection
In Vivo
Authors: Kofoed Eric M. , Yan Donghong , Katakam Anand K. , Reichelt Mike , Lin Baiwei , Kim Janice , Park Summer , Date Shailesh V. , Monk Ian R. , Xu Min , Austin Cary D. , Maurer Till , Tan Man-Wah 
Published: May 2016

ABSTRACT

De novo
guanine biosynthesis is an evolutionarily conserved pathway that creates sufficient nucleotides to support DNA replication, transcription, and translation. Bacteria can also salvage nutrients from the environment to supplement the
de novo
pathway, but the relative importance of either pathway during
Staphylococcus aureus
infection is not known. In
S. aureus
, genes important for both
de novo
and salvage pathways are regulated by a guanine riboswitch. Bacterial riboswitches have attracted attention as a novel class of antibacterial drug targets because they have high affinity for small molecules, are absent in humans, and regulate the expression of multiple genes, including those essential for cell viability. Genetic and biophysical methods confirm the existence of a bona fide guanine riboswitch upstream of an operon encoding xanthine phosphoribosyltransferase (
xpt
), xanthine permease (
pbuX
), inosine-5′-monophosphate dehydrogenase (
guaB
), and GMP synthetase (
guaA
) that represses the expression of these genes in response to guanine. We found that
S. aureus
guaB
and
guaA
are also transcribed independently of riboswitch control by alternative promoter elements. Deletion of
xpt-pbuX-guaB-guaA
genes resulted in guanine auxotrophy, failure to grow in human serum, profound abnormalities in cell morphology, and avirulence in mouse infection models, whereas deletion of the purine salvage genes
xpt-pbuX
had none of these effects. Disruption of
guaB
or
guaA
recapitulates the
xpt-pbuX-guaB-guaA
deletion
in vivo
. In total, the data demonstrate that targeting the guanine riboswitch alone is insufficient to treat
S. aureus
infections but that inhibition of
guaA
or
guaB
could have therapeutic utility.

IMPORTANCE
De novo
guanine biosynthesis and purine salvage genes were reported to be regulated by a guanine riboswitch in
Staphylococcus aureus
. We demonstrate here that this is not true, because alternative promoter elements that uncouple the
de novo
pathway from riboswitch regulation were identified. We found that in animal models of infection, the purine salvage pathway is insufficient for
S. aureus
survival in the absence of
de novo
guanine biosynthesis. These data suggest targeting the
de novo
guanine biosynthesis pathway may have therapeutic utility in the treatment of
S. aureus
infections.
Nasal and conjunctival screening prior to refractive surgery: an observational and cross-sectional study
Authors: Kitazawa Koji , Sotozono Chie , Sakamoto Masako , Sasaki Miho , Hieda Osamu , Yamasaki Toshihide , Kinoshita Shigeru 
Published: May 2016

ObjectivesTo investigate bacterial flora of clinically healthy conjunctiva and nasal cavity among patients prior to refractive surgery, as well as the characteristics of patients with methicillin-resistantStaphylococcus aureus(MRSA) colonisation.DesignObservational and cross-sectional study.SettingA single-centre study in Japan.Participants120 consecutive patients pre-refractive surgery.Primary and secondary outcome measures methodsSamples were obtained from the right conjunctival sac and the nasal cavity of 120 consecutive patients prior to refractive surgery and were then measured for the levels of the minimum inhibitory concentration (MIC) of antibiotics. Patients were interviewed regarding their occupation, family living situation and any personal history of atopic dermatitis, asthma, smoking or contact lens wear.ResultsPropionibacterium acnes(P. acnes) (32.5%) andStaphylococcus epidermidis(4.2%) were detected from the conjunctival sac.S. epidermidiswas the most commonly isolated (68.3%) in the nasal cavity. Of the 30 patients (25.0%) with colonisation byS. aureus, 2 patients, both of whom were healthcare workers with atopic dermatitis, were found to be positive for MRSA in the nasal cavity. A history of contact lens wear, asthma or smoking, as well as patient gender and age, was not associated with MRSA colonisation.ConclusionsThere were only 2 patients who were colonised with MRSA, both of whom were healthcare workers with atopic dermatitis.P. acneswas predominantly found in the conjunctival sac. Further study is needed to investigate the involvement between nasal and conjunctival flora, and risk factors for infectious complications.
Validity of whole slide images for scoring HER2 chromogenic in situ hybridisation in breast cancer
Authors: Al-Janabi Shaimaa , Horstman Anja , van Slooten Henk-Jan , Kuijpers Chantal , Lai-A-Fat Clifton , van Diest Paul J , Jiwa Mehdi 
Published: May 2016

AimWhole slide images (WSIs) have stimulated a paradigm shift from conventional to digital pathology in several applications within pathology. Due to the fact that WSIs have not yet been approved for primary diagnostics, validating their use for different diagnostic purposes is still mandatory. The aim of this study was to test the validity of WSI in assessing human epidermal growth factor receptor 2 (HER2) status in breast cancer specimens using chromogenic in situ hybridisation (CISH).Materials and methodsNinety-six HER2 CISH slides were scored by two observers on a light microscope (400× viewing magnification) and on WSI (40× scanning magnification, one focus plane) with a minimum of 6 weeks washout period. The concordance between digital and microscopic HER2 scores was assessed.ResultsDigitally, 93/96 cases could be assessed (96.8%). Microscopic and digital evaluation of HER2 amplification status were concordant in 68/93 cases ((73.1%, 95% CI: 0.639 −0.823), κ 0.588). CISH underscoring was most noticeable in the amplified and equivocal categories while the highest level concordance was seen in cases with a normal copy number. Additionally there was a noticeable tendency to underestimate the average HER2 scores on WSI: lower in 59 and higher in 11 cases. There was no major difference in time spent for microscopic scoring (86.9 s) and digital scoring (81.7 s).ConclusionsThere was a reasonable concordance between microscopic scoring and WSI-based scoring of HER2 copy number of CISH slides. Nevertheless, WSIs scanned on a single focal plane are insufficient to assess HER2 gene amplification status by scoring CISH due to the noticeable tendency towards digitally underestimating the number of HER2 spots. Scanning at multiple focus planes may offer better resolution for improved digital CISH spot counting.
Investigational New Drug Applications: A 1-Year Pilot Study on Rates and Reasons for Clinical Hold
Authors: Lapteva Larissa , Pariser Anne R 
Published: May 2016

Background The Food and Drug Administration (FDA)'s Center for Drug Evaluation and Research (CDER) receives about 1500 initial Investigational New Drug applications (INDs) per year. In the first 30 days after initial IND submission, FDA conducts a review to determine whether the proposed investigation is safe to proceed, and if not, the IND may be placed on clinical hold. Methods A retrospective study of rates and reasons for clinical hold for all initial INDs submitted to CDER in fiscal year (FY) 2013 was performed. INDs were assessed for reasons that led to clinical hold, included chemistry, manufacturing and controls (CMC), animal toxicology or clinical issues. INDs were further categorized by commercial versus research sponsorship, and rare versus common disease indications. All INDs placed on hold were reassessed by whether they remained on hold within the first year following hold imposition. Results CDER received 1410 initial INDs in FY 2013, of which 125 (8.9%) were placed on hold during the first 30 days after initial submission. Of the INDs placed on hold, more than half became active within the first year after first imposition of hold. CMC reasons were most commonly cited, followed by clinical, then toxicology reasons. There were no substantive differences in rates and reasons for hold between INDs for rare or common disease indications, or between commercial or research INDs. Conclusions The vast majority of initial INDs moved forward within 30 days after submission, and for those applications placed on hold, most became active within 1 year. The findings also suggest that many holds for new drug product programs can be avoided by following the available guidelines for investigational product development.
Assessment of Right Ventricular Systolic and Diastolic Parameters in Pulmonary Sarcoidosis
Authors: Ipek Emrah , Demirelli Selami , Ermis Emrah , Yıldırım Erkan , Öztürk Mustafa , Yolcu Mustafa , Araz Ömer , Kalkan Kamuran 
Published: May 2016

The clinical manifestations of cardiac involvement are seen in about 5% of patients with sarcoidosis; however, the incidence of cardiac involvement is higher in the autopsy series. About 14% of patients with pulmonary sarcoidosis (PS) without known cardiac involvement had diastolic dysfunction. We aimed to determine the role of parameters of right ventricular (RV) systolic and diastolic function in patients with PS without evidence of cardiac symptoms. Our study population consisted of 28 patients with grades 1–4 PS and 24 healthy subjects. This study was a clinical prospective cohort study. RV end-diastolic area was found to be significantly higher in the PS group (p=0.032). RV fractional area change (RVFAC) and tricuspid annular plane systolic excursion (TAPSE) were shown to be statistically lower in the PS group as compared to the control group (p<0.001). However, pulmonary arterial systolic pressure was significantly higher in the PS group (p=0.003). The tricuspid E velocity and E/A ratio were found to be significantly lower in the PS group (p=0.025 and 0.009, respectively), while the tricuspid A velocity and myocardial performance index (MPI) were found to be significantly lower in the control group (p=0.034 and 0.007, respectively). Early detection of cardiac involvement in PS is crucial because of the increased morbidity and risk of sudden cardiac death. RV diastolic Doppler parameters, tissue Doppler MPI, RVFAC and TAPSE are practical and cheap techniques in the diagnosis of cardiac involvement in patients with PS. A thorough transthorasic echocardiographic examination including RV systolic and diastolic functions and tissue Doppler MPI should constitute the mainstay of initial management and follow-up in PS.
Hydroxychloroquine in Patients with Systemic Lupus Erythematosus with End-Stage Renal Disease
Authors: Bethel Monique , Yang Frances M , Li Shuang , Nahman N Stanley , Oliver Alyce M , Machua Wambui , Carbone Laura D 
Published: May 2016

Objectives To determine dosing patterns and examine predictors of filled hydroxychloroquine (HCQ) prescriptions in patients with systemic lupus erythematosus (SLE) with end-stage renal disease (ESRD). Methods This was a retrospective cohort study of patients with SLE in the US Renal Data System (USRDS) database in fiscal year 2011. All patients were Medicare Part D beneficiaries. Patients with a diagnosis of SLE were identified by the International Classification of Diseases, 9th revision code 710. The prevalence, dosing, and predictors of filled HCQ prescriptions (demographic factors, dialysis type, and provider subspecialty) were determined. Results There were 10,276 patients with SLE identified; 2048 (19.9%) had a prescription for HCQ filled. The mean daily dose of HCQ was 321 mg (range 58–2000 mg). The most common daily doses were 200 (n=768, 37.5%) and 400 mg (n=1161, 56.7%). In multivariable logistic regression analysis, significant predictors of filled HCQ prescriptions included black/African-American race (OR 1.34, 95% CI (1.17 to 1.46)), hemodialysis (1.50, 95% CI (1.29 to 1.74)), and care from a rheumatologist (5.06, 95% CI (4.56 to 5.62)). Negative predictors of filled HCQ prescriptions included male gender (OR 0.72, 95% CI (0.63 to 0.83)) and those aged 45 years or older (compared to 20 years old and younger, aged 45–64 years, OR 0.66, 95% CI (0.54 to 0.79); aged 65–74 years, OR 0.58, 95% CI (0.44 to 0.76); aged 75 years and older, OR 0.56, 95% CI (0.39 to 0.82)). Conclusions In patients with SLE with ESRD, the dosing strategies for HCQ with regard to potential toxicity and disparities in prescribing patterns need further study.
Simvastatin Induces Death of Multiple Myeloma Cell Lines
Authors: Gronich Naomi , Drucker Liat , Shapiro Hava , Radnay Judith , Yarkoni Shai , Lishner Michael 
Published: May 2016

BackgroundAccumulating reports indicate that statins widely prescribed for hypercholesteromia have antineoplastic activity. We hypothesized that because statins inhibit farnesylation of Ras that is often mutated in multiple myeloma (MM), as well as the production of interleukin (IL)-6, a key cytokine in MM, they may have antiproliferative and/or proapoptotic effects in this malignancy.MethodsU266, RPMI 8226, and ARH77 were treated with simvastatin (0-30 μM) for 5 days. The following aspects were evaluated: viability (IC50), cell cycle, cell death, cytoplasmic calcium ion levels, supernatant IL-6 levels, and tyrosine kinase activity.ResultsExposure of all cell lines to simvastatin resulted in reduced viability with IC50s of 4.5 μM for ARH77, 8 μM for RPMI 8226, and 13 μM for U266. The decreased viability is attributed to cell-cycle arrest (U266, G1; RPMI 8226, G2M) and cell death. ARH77 underwent apoptosis, whereas U266 and RPMI 8226 displayed a more necrotic form of death. Cytoplasmic calcium levels decreased significantly in all treated cell lines. IL-6 secretion from U266 cells was abrogated on treatment with simvastatin, whereas total tyrosine phosphorylation was unaffected.ConclusionsSimvastatin displays significant antimyeloma activity in vitro. Further research is warranted for elucidation of the modulated molecular pathways and clinical relevance.
Clinical Experience with Drotrecogin Alfa in Treating Gram-Positive and -Negative Pathogens in Patients with Severe Sepsis
Authors: Cone Lawrence A. , Stone Richard A. , Jesser Kenneth , Nelson Richard 
Published: May 2016

BackgroundNewer concepts in the management of severe sepsis and, in particular, in the understanding of the relationship between proinflammatory and procoagulant activities during severe infection have led to the introduction of activated protein C (drotrecogin) into the therapeutic program. The combination of effective antimicrobial therapy, aggressive supportive care, and efforts to antagonize procoagulants and inhibitors of fibrinolysis was used in this study.MethodsWe treated 12 patients with severe sepsis using this combination of antimicrobial agents and drotrecogin. All patients presented with hypotension and organ failure and some with multiple organ failure. Infected patients were separated into those with gram-positive and those with gram-negative infections.ResultsIn contrast to an expected mortality rate of nearly 40% in this group of patients, only 2 (9%) expired. Both deaths were due to infection by gram-negative organisms in patients with complicated abdominal infections and concurrent cancer. All patients with gram-positive organisms survived.ConclusionThose patients with infections caused by gram-positive organisms seemed to have a better prognosis than those with gram-negative infections, perhaps because their illnesses are less complicated by local disease. Although our study is small, it suggests that activated protein C will have a significant beneficial effect on the future treatment of severe sepsis and can reduce the mortality rate significantly. Further improvement in survival rates will require more effective treatment of local disease and associated noninfectious ailments.
Prevalence and molecular characterisation of Giardia duodenalis in calves with diarrhoea
Authors: Lee S. H. , VanBik D. , Kim H. Y. , Cho A. , Kim J. W. , Byun J. W. , Oem J. K. , Oh S. I. , Kwak D. 
Published: May 2016

The aim of this study was to investigate the prevalence of Giardia duodenalis in diarrhoeal faeces from calves that were reared in Korea using PCR and ELISA. Diarrhoeal faecal samples were collected from 590 calves (<3 months old) throughout the country from November 2013 through March 2015. Data were analysed according to the region of collection, season, and type of diarrhoea. Of the 590 collected faecal samples, 77 (13.1 per cent) and 78 (13.2 per cent; true prevalence 9.1 per cent) tested positive by PCR and ELISA, respectively. The results from both testing methods were in agreement in 501 (84.9 per cent) samples, with a κ value of 0.34, which suggests fair agreement. The PCR results showed a higher prevalence in summer and in cases of haemorrhagic diarrhoea (P<0.05), while the ELISA results showed a lower prevalence in cases of pasty diarrhoea (P<0.05). Phylogenetic analysis of the β‐giardin gene sequences of G duodenalis showed that the sequences detected in this study belonged to assemblage E, which is specific to cattle and livestock. The higher prevalence of giardiasis in calves with haemorrhagic diarrhoea found in this study differed from previous studies. Therefore, researchers and veterinarians should be aware of the possible involvement of giardiasis in haemorrhagic diarrhoea.
The Role of Omalizumab in the Treatment of Severe Allergic Asthma
Authors: Chapman Kenneth R , Cartier Andre , Hébert Jacques , McIvor R Andrew , Schellenberg R Robert 
Published: May 2016

BACKGROUND: A novel anti-immunoglobulin E (anti-IgE) therapy for asthma, omalizumab, has been approved for use in Canada.OBJECTIVE: To review the basic and clinical data for omalizumab, and to examine its possible role for asthma management in Canada.METHODS: A literature search from 1960 to 2006 was conducted in MEDLINE to identify studies of omalizumab. In addition, abstracts from recent respiratory and allergy scientific meetings were sought, and any unpublished data were requested from the manufacturer. A consensus panel of respiratory and allergy specialists reviewed and summarized the data, and derived a set of recommendations for omalizumab use.RESULTS: Omalizumab is a humanized monoclonal antibody designed to bind to the C epsilon 3 domain of the IgE molecule, forming soluble immune complexes that are cleared by the reticuloendothelial system. Subcutaneous injections, given at two- or fourweek intervals at the recommended dose, result in a rapid decrease in free circulating IgE levels. In two phase III clinical trials of 1405 adult and adolescent patients with moderate to severe asthma maintained on moderate doses of inhaled corticosteroids (ICS), omalizumab reduced exacerbation rates compared with placebo, and was associated with improved symptoms and a greater corticosteroid-sparing effect. In a trial of 419 patients with severe disease that was uncontrolled despite the use of high-dose ICS and concurrent long-acting beta2-agonists, severe exacerbations were 50% less frequent in omalizumabtreated patients than in control subjects. Retrospective analyses have identified the characteristics of patients most likely to respond to omalizumab treatment.RECOMMENDATIONS: Omalizumab may be considered as a potential adjunctive therapy in atopic patients with severe asthma uncontrolled by conventional therapy with optimal doses of ICS and appropriate adjunctive therapy (eg, long-acting beta2-agonists). Typically, patients are identified by the need for frequent short course or continuous oral corticosteroids. Therapy should be initiated only after review by a specialist to confirm the diagnosis and that conventional therapy is optimal.
Renalase Expression by Melanoma and Tumor-Associated Macrophages Promotes Tumor Growth through a STAT3-Mediated Mechanism
Authors: Hollander Lindsay , Guo Xiaojia , Velazquez Heino , Chang John , Safirstein Robert , Kluger Harriet , Cha Charles , Desir Gary V. 
Published: May 2016

Abstract
To sustain their proliferation, cancer cells overcome negative-acting signals that restrain their growth and promote senescence and cell death. Renalase (RNLS) is a secreted flavoprotein that functions as a survival factor after ischemic and toxic injury, signaling through the plasma calcium channel PMCA4b to activate the PI3K/AKT and MAPK pathways. We show that RNLS expression is increased markedly in primary melanomas and CD163+ tumor-associated macrophages (TAM). In clinical specimens, RNLS expression in the tumor correlated inversely with disease-specific survival, suggesting a pathogenic role for RNLS. Attenuation of RNLS by RNAi, blocking antibodies, or an RNLS-derived inhibitory peptide decreased melanoma cell survival, and anti-RNLS therapy blocked tumor growth in vivo in murine xenograft assays. Mechanistic investigations showed that increased apoptosis in tumor cells was temporally related to p38 MAPK-mediated Bax activation and that increased cell growth arrest was associated with elevated expression of the cell-cycle inhibitor p21. Overall, our results established a role for the secreted flavoprotein RNLS in promoting melanoma cell growth and CD163+ TAM in the tumor microenvironment, with potential therapeutic implications for the management of melanoma. Cancer Res; 76(13); 3884–94. ©2016 AACR.
Early Life Body Fatness, Serum Anti-Müllerian Hormone, and Breast Density in Young Adult Women
Authors: Bertrand Kimberly A. , Baer Heather J. , Orav E. John , Klifa Catherine , Kumar Ajay , Hylton Nola M. , LeBlanc Erin S. , Snetselaar Linda G. , Van Horn Linda , Dorgan Joanne F. 
Published: May 2016

Abstract
Background: Emerging evidence suggests positive associations between serum anti-Müllerian hormone (AMH), a marker of ovarian function, and breast cancer risk. Body size at young ages may influence AMH levels, but few studies have examined this. Also, no studies have examined the relation of AMH levels with breast density, a strong predictor of breast cancer risk.
Methods: We examined associations of early life body fatness, AMH concentrations, and breast density among 172 women in the Dietary Intervention Study in Children (DISC). Height and weight were measured at baseline (ages 8–10) and throughout adolescence. Serum AMH concentrations and breast density were assessed at ages 25–29 at the DISC 2006 Follow-up visit. We used linear mixed effects models to quantify associations of AMH (dependent variable) with quartiles of age-specific youth body mass index (BMI) Z-scores (independent variable). We assessed cross-sectional associations of breast density (dependent variable) with AMH concentration (independent variable).
Results: Neither early life BMI nor current adult BMI was associated with AMH concentrations. There were no associations between AMH and percent or absolute dense breast volume. In contrast, women with higher AMH concentrations had significantly lower absolute nondense breast volume (Ptrend &lt; 0.01).
Conclusions: We found no evidence that current or early life BMI influences AMH concentrations in later life. Women with higher concentrations of AMH had similar percent and absolute dense breast volume, but lower nondense volume.
Impact: These results suggest that AMH may be associated with lower absolute nondense breast volume; however, future prospective studies are needed to establish temporality. Cancer Epidemiol Biomarkers Prev; 25(7); 1151–7. ©2016 AACR.
БІОФІЗИЧНА ХАРАКТЕРИСТИКА ВОЛОГИ ПОВІТРЯ, ЩО ВИДИХАЄТЬСЯ, У ХВОРИХ НА ТУБЕРКУЛЬОЗ ЛЕГЕНЬ У ДИНАМІЦІ ЛІКУВАННЯ
Authors: Bazhora Yu. I. , Yermuraki P. P. , Chesnokova M. M. , Smetyuk O. O. , Abdulrakhman Ali Sleman Sayeb 
Published: May 2016

<p>Волога повітря, що видихається, привертає увагу як матеріал для вивчення біологічних компонентів. Пов'язано це з тим, що конденсат вологи повітря, що видихається (КВВП), формується в альвеолах легеневої тканини і його складові відображають стан місцевого гомеостазу системи дихання. Крім того, метод отримання КВВП належить до неінвазивних, що також привертає увагу<br />дослідників.<br />У попередніх дослідженнях нами була показана діагностична цінність методу лазерної кореляційної спектроскопії (ЛКС) у дослідженнях біофізичних властивостей КВВП при захворюваннях органів дихання.</p>