Detection of human papillomavirus DNA sequences in oral lesions using polymerase chain reaction

The purpose of the present study was to estimate the frequency of HPV DNA in four groups of oral lesions, including oral squamous cell carcinoma. Sixty paraffin-embedded oral tissue samples were examined for the presence of HPV DNAs using the PCR technique. These specimens were obtained from patients with oral squamous cell carcinoma (OSCC), leukoplakia, oral lichen planus (OLP), and pyogenic granuloma (PG). Consensus primers for L1 region (MY09 and MY11) and specific primers were used for detection of HPV DNA sequences in this study. we detected HPV DNA in 60% (9 out of 15) of OSCCs, 26.7% (4 out of 15) of leukoplakia, 13.3% (2 out of 15) of OLPs, and 6.7% (1 out of 15) of PGs. Statistical analysis showed that the prevalence of HPV in OSCC was significantly higher than other groups (P < 0.05). The frequency of HPV-16 and 18 detection in OSCC samples were 40% and 20%, respectively. The prevalence of these high risk HPVs was significantly higher in OSCC group (P < 0.05). The results of the present study show a successive increase of detection rate of HPV-16 and 18 DNAs from low level in samples of pyogenic granuloma and non-premalignant or questionably premalignant lesions of OLP to premalignant leukoplakia and to OSCC. © 2007 Tehran University of Medical Sciences. All rights reserved

The correlation of RNase A enzymatic activity with the changes in the distance between Nepsilon2-His12 and N delta1-His119 upon addition of stabilizing and destabilizing salts.

The effect of stabilizing and destabilizing salts on the catalytic behavior of ribonuclease A (RNase A) was investigated at pH 7.5 and 25 degrees C, using spectrophotometric, viscometric and molecular dynamic methods. The changes in the distance between N(epsilon2) of His(12) and N(delta1) of His(119) at the catalytic center of RNase A upon the addition of sodium sulfate, sodium hydrogen sulfate and sodium thiocyanate were evaluated by molecular dynamic methods. The compactness and expansion in terms of Stokes radius of RNase A upon the addition of sulfate ions as kosmotropic salts, and thiocyanate ion as a chaotropic salt, were estimated by viscometric measurements. Enzyme activity was measured using cytidine 2', 3'-cyclic monophosphate as a substrate. The results from the measurements of distances between N(epsilon2) of His(12) and N(delta1) of His(119) and Stokes radius suggest (i) that the presence of sulfate ions decreases the distance between the catalytic His residues and increases the globular compactness, and (ii) that there is an expansion of the enzyme surface as well as elongation of the catalytic center in the presence of thiocyanate ion. These findings are in agreement with activity measurements

X-Ray, UV, and radio timing observations of the radio galaxy 3C 120

We report the results of monitoring of the radio galaxy 3C 120 with the Neil Gehrels Swift Observatory, Very Long Baseline Array, and Metsähovi Radio Observatory. The UV-optical continuum spectrum and R-band polarization can be explained by a superposition of an inverted-spectrum source with a synchrotron component containing a disordered magnetic field. The UV-optical and X-ray light curves include dips and flares, while several superluminal knots appear in the parsec-scale jet. The recovery time of the second dip was longer at UV-optical wavelengths, in conflict with a model in which the inner accretion disk (AD) is disrupted during a dip and then refilled from outer to inner radii. We favor an alternative scenario in which occasional polar alignments of the magnetic field in the disk and corona cause the flux dips and formation of shocks in the jet. Similar to observations of Seyfert galaxies, intra-band time lags of flux variations are longer than predicted by the standard AD model. This suggests that scattering or some other reprocessing occurs. The 37 GHz light curve is well-correlated with the optical-UV variations, with a ∼20 day delay. A radio flare in the jet occurred in a superluminal knot 0.14 milliarcseconds downstream of the 43 GHz "core," which places the site of the preceding X-ray/UV/optical flare within the core 0.5–1.3 pc from the black hole. The inverted UV-optical flare spectrum can be explained by a nearly monoenergetic electron distribution with energy similar to the minimum energy inferred in the TeV γ-ray emitting regions of some BL Lacertae objects.The authors thank I. McHardy, R. Antonucci, and B. Punsly for informative discussions. This study was supported in part by NASA through Swift Guest Investigator grant NNX16AN69G, Fermi Guest Investigator grants NNX14AQ58G and 80NSSC17K0649, and by National Science Foundation grant AST-1615796. This publication makes use of data obtained at the Metsahovi Radio Observatory, operated by Aalto University in Finland. The VLBA is an instrument of the National Radio Astronomy Observatory. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. (NNX16AN69G - NASA; NNX14AQ58G - NASA; 80NSSC17K0649 - NASA; AST-1615796 - National Science Foundation; National Aeronautics and Space Administration)Accepted manuscrip

The environment of radio galaxies: a signature of AGN feedback at high redshifts

We use the semi-analytical model of galaxy formation GALFORM to characterize an indirect signature of active galactic nucleus (AGN) feedback in the environment of radio galaxies at high redshifts. The predicted environment of radio galaxies is denser than that of radio-quiet galaxies with the same stellar mass. This is consistent with observational results from the CARLA survey. Our model shows that the differences in environment are due to radio galaxies being hosted by dark matter haloes that are ∼1.5 dex more massive than those hosting radio-quiet galaxies with the same stellar mass. By running a control simulation in which AGN feedback is switched off, we identify AGN feedback as the primary mechanism affecting the build up of the stellar component of radio galaxies, thus explaining the different environment in radio galaxies and their radio-quiet counterparts. The difference in host halo mass between radio-loud and radio-quiet galaxies translates into different galaxies populating each environment. We predict a higher fraction of passive galaxies around radio-loud galaxies compared to their radio-quiet counterparts. Furthermore, such a high fraction of passive galaxies shapes the predicted infrared luminosity function in the environment of radio galaxies in a way that is consistent with observational findings. Our results suggest that the impact of AGN feedback at high redshifts and environmental mechanisms affecting galaxies in high halo masses can be revealed by studying the environment of radio galaxies, thus providing new constraints on galaxy formation physics at high redshifts

Multimessenger Characterization of Markarian 501 during Historically Low X-Ray and γ-Ray Activity

We study the broadband emission of Mrk 501 using multiwavelength observations from 2017 to 2020 performed with a multitude of instruments, involving, among others, MAGIC, Fermi's Large Area Telescope (LAT), NuSTAR, Swift, GASP-WEBT, and the Owens Valley Radio Observatory. Mrk 501 showed an extremely low broadband activity, which may help to unravel its baseline emission. Nonetheless, significant flux variations are detected at all wave bands, with the highest occurring at X-rays and very-high-energy (VHE) 3-rays. A significant correlation (&gt;3σ) between X-rays and VHE 3-rays is measured, supporting leptonic scenarios to explain the variable parts of the emission, also during low activity. This is further supported when we extend our data from 2008 to 2020, and identify, for the first time, significant correlations between the Swift X-Ray Telescope and Fermi-LAT. We additionally find correlations between high-energy 3-rays and radio, with the radio lagging by more than 100 days, placing the 3-ray emission zone upstream of the radio-bright regions in the jet. Furthermore, Mrk 501 showed a historically low activity in X-rays and VHE 3-rays from mid-2017 to mid-2019 with a stable VHE flux (&gt;0.2 TeV) of 5% the emission of the Crab Nebula. The broadband spectral energy distribution (SED) of this 2 yr long low state, the potential baseline emission of Mrk 501, can be characterized with one-zone leptonic models, and with (lepto)-hadronic models fulfilling neutrino flux constraints from IceCube. We explore the time evolution of the SED toward the low state, revealing that the stable baseline emission may be ascribed to a standing shock, and the variable emission to an additional expanding or traveling shock. © 2023. The Author(s). Published by the American Astronomical Society

Multi-messenger characterization of Mrk 501 during historically low X-ray and γ\gamma-ray activity

We study the broadband emission of Mrk 501 using multi-wavelength observations from 2017 to 2020 performed with a multitude of instruments, involving, among others, MAGIC, Fermi-LAT, NuSTAR, Swift, GASP-WEBT, and OVRO. Mrk 501 showed an extremely low broadband activity, which may help to unravel its baseline emission. Nonetheless, significant flux variations are detected at all wavebands, with the highest occurring at X-rays and very-high-energy (VHE) $\gamma$-rays. A significant correlation ($>$3$\sigma$) between X-rays and VHE $\gamma$-rays is measured, supporting leptonic scenarios to explain the variable parts of the emission, also during low activity. This is further supported when we extend our data from 2008 to 2020, and identify, for the first time, significant correlations between Swift-XRT and Fermi-LAT. We additionally find correlations between high-energy $\gamma$-rays and radio, with the radio lagging by more than 100 days, placing the $\gamma$-ray emission zone upstream of the radio-bright regions in the jet. Furthermore, Mrk 501 showed a historically low activity in X-rays and VHE $\gamma$-rays from mid-2017 to mid-2019 with a stable VHE flux ($>$0.2 TeV) of 5% the emission of the Crab Nebula. The broadband spectral energy distribution (SED) of this 2-year-long low-state, the potential baseline emission of Mrk 501, can be characterized with one-zone leptonic models, and with (lepto)-hadronic models fulfilling neutrino flux constraints from IceCube. We explore the time evolution of the SED towards the low-state, revealing that the stable baseline emission may be ascribed to a standing shock, and the variable emission to an additional expanding or traveling shock.Comment: 56 pages, 30 figures, 14 tables, submitted. Corresponding authors are L. Heckmann, D. Paneque, S. Gasparyan, M. Cerruti, and N. Sahakya

Multiwavelength Observations of the Blazar BL Lacertae: A New Fast TeV Gamma-Ray Flare

Combined with measurements made by very-long-baseline interferometry, the observations of fast TeV gamma-ray flares probe the structure and emission mechanism of blazar jets. However, only a handful of such flares have been detected to date, and only within the last few years have these flares been observed from lower-frequency-peaked BL. Lac objects and flat-spectrum radio quasars. We report on a fast TeV gamma-ray flare from the blazar BL. Lacertae observed by the Very Energetic Radiation Imaging Telescope Array System (VERITAS). with a rise time of similar to 2.3 hr and a decay time of similar to 36 min. The peak flux above 200 GeV is (4.2 +/- 0.6) x 10(-6) photon m(-2) s(-1) measured with a 4-minute-binned light curve, corresponding to similar to 180% of the flux that is observed from the Crab Nebula above the same energy threshold. Variability contemporaneous with the TeV gamma-ray flare was observed in GeV gamma-ray, X-ray, and optical flux, as well as in optical and radio polarization. Additionally, a possible moving emission feature with superluminal apparent velocity was identified in Very Long Baseline Array observations at 43 GHz, potentially passing the radio core of the jet around the time of the gamma-ray flare. We discuss the constraints on the size, Lorentz factor, and location of the emitting region of the flare, and the interpretations with several theoretical models that invoke relativistic plasma passing stationary shocks

Ten golden rules for optimal antibiotic use in hospital settings: the WARNING call to action

Antibiotics are recognized widely for their benefits when used appropriately. However, they are often used inappropriately despite the importance of responsible use within good clinical practice. Effective antibiotic treatment is an essential component of universal healthcare, and it is a global responsibility to ensure appropriate use. Currently, pharmaceutical companies have little incentive to develop new antibiotics due to scientific, regulatory, and financial barriers, further emphasizing the importance of appropriate antibiotic use. To address this issue, the Global Alliance for Infections in Surgery established an international multidisciplinary task force of 295 experts from 115 countries with different backgrounds. The task force developed a position statement called WARNING (Worldwide Antimicrobial Resistance National/International Network Group) aimed at raising awareness of antimicrobial resistance and improving antibiotic prescribing practices worldwide. The statement outlined is 10 axioms, or “golden rules,” for the appropriate use of antibiotics that all healthcare workers should consistently adhere in clinical practice

ASSESSMENT OF AWARENESS OF RECOMMEN-DATIONS FOR PREVENTION OF BACTERIAL ENDOCARDITIS AMONG A GROUP OF 136 IRANIAN DENTAL AND MEDICAL STUDENTS

Bacterial endocarditis is a serious disease that could occur after invasive dental procedures. Despite a large number of papers written about the knowledge of prevention of bacterial endocarditis among health care workers in western countries, little is known about awareness of this subject among practitioners and students in other countries. The purpose of the present study was to assess the knowledge of recommendations for prevention of bacterial endocarditis among a group of Iranian dental and medical students. A multiple choice test that included 15 questions about bacterial endocarditis and antibiotic prophylaxis was developed. The questionnaires were distributed to 136 dental and medical students who had passed a theoretical course about bacterial endocarditis successfully in the past. Success was defined as correct answers to at least 8 of the 15 questions. Of 136 students participating in this study, 34 (25%) passed the test successfully. The pass-rate of dental students (38%) was significantly higher than that of medical students (13.5%) (P &amp;lt; 0.05). The mean mark of dental and medical students was 6.74 &amp;plusmn; 2.28 and 4.81 &amp;plusmn; 2.1, respectively (P &amp;lt; 0.05). No significant difference in success rates or mean marks found according to sex or age in the present study.&quot;nThe results of the present study demonstrate an important lack of knowledge regarding prevention of bacterial endocarditis among a group of Iranian dental and medical students and the need for improved education in this field