Chlamydia trachomatis is responsible for both trachoma and sexually transmitted infections, causing substantial morbidity and economic cost globally. Despite this, our knowledge of its population and ...evolutionary genetics is limited. Here we present a detailed phylogeny based on whole-genome sequencing of representative strains of C. trachomatis from both trachoma and lymphogranuloma venereum (LGV) biovars from temporally and geographically diverse sources. Our analysis shows that predicting phylogenetic structure using ompA, which is traditionally used to classify Chlamydia, is misleading because extensive recombination in this region masks any true relationships present. We show that in many instances, ompA is a chimera that can be exchanged in part or as a whole both within and between biovars. We also provide evidence for exchange of, and recombination within, the cryptic plasmid, which is another key diagnostic target. We used our phylogenetic framework to show how genetic exchange has manifested itself in ocular, urogenital and LGV C. trachomatis strains, including the epidemic LGV serotype L2b.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
We report on simultaneous radio and X-ray observations of the repeating fast radio burst source FRB 180916.J0158+65 using the Canadian Hydrogen Intensity Mapping Experiment (CHIME), Effelsberg, and ...Deep Space Network (DSS-14 and DSS-63) radio telescopes and the Chandra X-ray Observatory. During 33 ks of Chandra observations, we detect no radio bursts in overlapping Effelsberg or Deep Space Network observations and a single burst during CHIME/FRB source transits. We detect no X-ray events in excess of the background during the Chandra observations. These non-detections imply a 5 limit of <5 × 10−10 erg cm−2 for the 0.5-10 keV fluence of prompt emission at the time of the radio burst and 1.3 × 10−9 erg cm−2 at any time during the Chandra observations. Given the host-galaxy redshift of FRB 180916.J0158+65 (z ∼ 0.034), these correspond to energy limits of <1.6 × 1045 erg and <4 × 1045 erg, respectively. We also place a 5 limit of <8 × 10−15 erg s−1 cm−2 on the 0.5-10 keV absorbed flux of a persistent source at the location of FRB 180916.J0158+65. This corresponds to a luminosity limit of <2 × 1040 erg s−1. Using an archival set of radio bursts from FRB 180916.J0158+65, we search for prompt gamma-ray emission in Fermi/GBM data but find no significant gamma-ray bursts, thereby placing a limit of 9 × 10−9 erg cm−2 on the 10-100 keV fluence. We also search Fermi/LAT data for periodic modulation of the gamma-ray brightness at the 16.35 days period of radio burst activity and detect no significant modulation. We compare these deep limits to the predictions of various fast radio burst models, but conclude that similar X-ray constraints on a closer fast radio burst source would be needed to strongly constrain theory.
We report the detection of a single burst from the first-discovered repeating fast radio burst (FRB) source, FRB 121102, with the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope, ...which operates in the frequency band 400-800 MHz. The detected burst occurred on 2018 November 19 and its emission extends down to at least 600 MHz, the lowest frequency detection of this source yet. The burst, detected with a significance of 23.7 , has fluence 12 3 Jy ms and shows complex time and frequency morphology. The 34 ms width of the burst is the largest seen for this object at any frequency. We find evidence of subburst structure that drifts downward in frequency at a rate of −3.9 0.2 MHz ms−1. Our best fit tentatively suggests a dispersion measure of 563.6 0.5 pc cm−3, which is 1% higher than previously measured values. We set an upper limit on the scattering time at 500 MHz of 9.6 ms, which is consistent with expectations from the extrapolation from higher-frequency data. We have exposure to the position of FRB 121102 for a total of 11.3 hr within the FWHM of the synthesized beams at 600 MHz from 2018 July 25 to 2019 February 25. We estimate on the basis of this single event an average burst rate for FRB 121102 of 0.1-10 per day in the 400-800 MHz band for a median fluence threshold of 7 Jy ms in the stated time interval.
In pigs, Chlamydia suis has been associated with respiratory disease, diarrhea and conjunctivitis, but there is a high rate of inapparent C. suis infection found in the gastrointestinal tract of ...pigs. Tetracycline resistance in C. suis has been described in the USA, Italy, Switzerland, Belgium, Cyprus and Israel. Tetracyclines are commonly used in pig production due to their broad-spectrum activity and relatively low cost. The aim of this study was to isolate clinical C. suis samples in cell culture and to evaluate their antibiotic susceptibility in vitro under consideration of antibiotic treatment on herd level. Swab samples (n = 158) identified as C. suis originating from 24 farms were further processed for isolation, which was successful in 71% of attempts with a significantly higher success rate from fecal swabs compared to conjunctival swabs. The farms were divided into three treatment groups: A) farms without antibiotic treatment, B) farms with prophylactic oral antibiotic treatment of the whole herd consisting of trimethoprime, sulfadimidin and sulfathiazole (TSS), or C) farms giving herd treatment with chlortetracycline with or without tylosin and sulfadimidin (CTS). 59 isolates and their corresponding clinical samples were selected and tested for the presence or absence of the tetracycline resistance class C gene tet(C) by conventional PCR and isolates were further investigated for their antibiotic susceptibility in vitro. The phenotype of the investigated isolates was either classified as tetracycline sensitive (Minimum inhibitory concentration MIC < 2 μg/ml), intermediate (2 μg/ml ≤ MIC < 4 μg/ml) or resistant (MIC ≥ 4 μg/ml). Results of groups and individual pigs were correlated with antibiotic treatment and time of sampling (beginning/end of the fattening period). We found clear evidence for selective pressure as absence of antibiotics led to isolation of only tetracycline sensitive or intermediate strains whereas tetracycline treatment resulted in a greater number of tetracycline resistant isolates.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Assessment of Neuropathic Pain in Primary Care Haanpää, Maija L., MD, PhD; Backonja, Misha-Miroslav, MD, PhD; Bennett, Michael I., MB, ChB ...
The American journal of medicine,
10/2009, Letnik:
122, Številka:
10
Journal Article
Recenzirano
Abstract Management of patients presenting with chronic pain is a common problem in primary care. Essentially, the classification of chronic pain falls into 3 broad categories: (1) pain owing to ...tissue disease or damage (nociceptive pain), (2) pain caused by somatosensory system disease or damage (neuropathic pain), and (3) pain without a known somatic background. Key challenges in developing a targeted holistic approach to treatment include appropriate diagnosis of the cause or causes of pain; identifying the type of pain and assessing the relative importance of its various components; and determining appropriate treatment. In clinical examination, sensory abnormalities are the crucial findings leading to a diagnosis of neuropathic pain, for which pharmacotherapy with antidepressants and anticonvulsants represents the cornerstone of medical treatment. Chronic neuropathic pain is underrecognized and undertreated, yet primary care physicians are uniquely placed on the frontlines of patient management, where they can play a pivotal role in treatment and prevention through diagnosis, therapy, follow-up, and referral. This review provides guidance in understanding and identifying the neuropathic contribution to pain presenting in primary care; assessing its severity through patient history, physical examination, and appropriate diagnostic tests; and establishing a rational treatment plan.
Neutron scattering measurements on the pyrochlore magnet Ce2Zr2O7 reveal an unusual crystal field splitting of its lowest J=5/2 multiplet, such that its ground-state doublet is composed of mJ=±3/2, ...giving these doublets a dipole-octupole (DO) character with local Ising anisotropy. Its magnetic susceptibility shows weak antiferromagnetic correlations with θCW=−0.4(2) K, leading to a naive expectation of an all-in, all-out ordered state at low temperatures. Instead, our low-energy inelastic neutron scattering measurements show a dynamic quantum spin ice state, with suppressed scattering near |Q|=0, and no long-range order at low temperatures. This is consistent with recent theory predicting symmetry-enriched U(1) quantum spin liquids for such DO doublets decorating the pyrochlore lattice. Finally, we show that disorder, especially oxidation of powder samples, is important in Ce2Zr2O7 and could play an important role in the low-temperature behavior of this material.
Abstract
We present new radio and optical images of the nearest radio galaxy Centaurus A and its host galaxy NGC 5128. We focus our investigation on the northern transition region, where energy is ...transported from the ∼5 kpc (∼5 arcmin) scales of the northern inner lobe (NIL) to the ∼30 kpc (∼30 arcmin) scales of the northern middle lobe (NML). Our Murchison Widefield Array observations at 154 MHz and our Parkes radio telescope observations at 2.3 GHz show diffuse radio emission connecting the NIL to the NML, in agreement with previous Australia Telescope Compact Array observations at 1.4 GHz. Comparison of these radio data with our wide-field optical emission-line images show the relationship between the NML radio emission and the ionized filaments that extend north from the NIL, and reveal a new ionized filament to the east, possibly associated with a galactic wind. Our deep optical images show clear evidence for a bipolar outflow from the central galaxy extending to intermediate scales, despite the non-detection of a southern radio counterpart to the NML. Thus, our observational overview of Centaurus A reveals a number of features proposed to be associated with active galactic nucleus feedback mechanisms, often cited as likely to have significant effects in galaxy evolution models. As one of the closest galaxies to us, Centaurus A therefore provides a unique laboratory to examine feedback mechanisms in detail.
General cognitive function is substantially heritable across the human life course from adolescence to old age. We investigated the genetic contribution to variation in this important, health- and ...well-being-related trait in middle-aged and older adults. We conducted a meta-analysis of genome-wide association studies of 31 cohorts (N=53,949) in which the participants had undertaken multiple, diverse cognitive tests. A general cognitive function phenotype was tested for, and created in each cohort by principal component analysis. We report 13 genome-wide significant single-nucleotide polymorphism (SNP) associations in three genomic regions, 6q16.1, 14q12 and 19q13.32 (best SNP and closest gene, respectively: rs10457441, P=3.93 × 10(-9), MIR2113; rs17522122, P=2.55 × 10(-8), AKAP6; rs10119, P=5.67 × 10(-9), APOE/TOMM40). We report one gene-based significant association with the HMGN1 gene located on chromosome 21 (P=1 × 10(-6)). These genes have previously been associated with neuropsychiatric phenotypes. Meta-analysis results are consistent with a polygenic model of inheritance. To estimate SNP-based heritability, the genome-wide complex trait analysis procedure was applied to two large cohorts, the Atherosclerosis Risk in Communities Study (N=6617) and the Health and Retirement Study (N=5976). The proportion of phenotypic variation accounted for by all genotyped common SNPs was 29% (s.e.=5%) and 28% (s.e.=7%), respectively. Using polygenic prediction analysis, ~1.2% of the variance in general cognitive function was predicted in the Generation Scotland cohort (N=5487; P=1.5 × 10(-17)). In hypothesis-driven tests, there was significant association between general cognitive function and four genes previously associated with Alzheimer's disease: TOMM40, APOE, ABCG1 and MEF2C.
We report on the detection of seven bursts from the periodically active, repeating fast radio burst (FRB) source FRB 180916.J0158+65 in the 300-400 MHz frequency range with the Green Bank Telescope ...(GBT). Emission in multiple bursts is visible down to the bottom of the GBT band, suggesting that the cutoff frequency (if it exists) for FRB emission is lower than 300 MHz. Observations were conducted during predicted periods of activity of the source, and had simultaneous coverage with the Low Frequency Array (LOFAR) and the FRB backend on the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope. We find that one of the GBT-detected bursts has potentially associated emission in the CHIME band (400-800 MHz) but we detect no bursts in the LOFAR band (110-190 MHz), placing a limit of on the spectral index of broadband emission from the source. We also find that emission from the source is severely band-limited with burst bandwidths as low as ∼40 MHz. In addition, we place the strictest constraint on observable scattering of the source, <1.7 ms at 350 MHz, suggesting that the circumburst environment does not have strong scattering properties. Additionally, knowing that the circumburst environment is optically thin to free-free absorption at 300 MHz, we find evidence against the association of a hyper-compact H ii region or a young supernova remnant (age <50 yr) with the source.
Pandemics and subsequent lifestyle restrictions such as ‘lockdowns’ may have unintended consequences, including alterations in body weight. This systematic review assesses the impact of pandemic ...confinement on body weight and identifies contributory factors. A comprehensive literature search was performed in seven electronic databases and in grey sources from their inception until 1 July 2020 with an update in PubMed and Scopus on 1 February 2021. In total, 2361 unique records were retrieved, of which forty-one studies were identified eligible: one case–control study, fourteen cohort and twenty-six cross-sectional studies (469, 362 total participants). The participants ranged in age from 6 to 86 years. The proportion of female participants ranged from 37 % to 100 %. Pandemic confinements were associated with weight gain in 7·2–72·4 % of participants and weight loss in 11·1–32·0 % of participants. Weight gain ranged from 0·6 (sd 1·3) to 3·0 (sd 2·4) kg, and weight loss ranged from 2·0 (sd 1·4) to 2·9 (sd 1·5) kg. Weight gain occurred predominantly in participants who were already overweight or obese. Associated factors included increased consumption of unhealthy food with changes in physical activity and altered sleep patterns. Weight loss during the pandemic was observed in individuals with previous low weight, and those who ate less and were more physically active before lockdown. Maintaining a stable weight was more difficult in populations with reduced income, particularly in individuals with lower educational attainment. The findings of this systematic review highlight the short-term effects of pandemic confinements.
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