3,602 research outputs found
Antimicrobial susceptibility assays for Neisseria gonorrhoeae: a proof-of-principle population-based retrospective analysis
No full textBackground: Neisseria gonorrhoeae treatment guided by molecular antimicrobial susceptibility assays could improve treatment options and antimicrobial stewardship; however, few commercial assays are available. We aimed to investigate antimicrobial susceptibility of N gonorrhoeae isolates in New South Wales, Australia, and estimate the potential usefulness of hypothetical combinations of rapid molecular antimicrobial susceptibility assays. Methods: In this proof-of-principle, population-based, retrospective analysis, we assessed N gonorrhoeae susceptibility data for ceftriaxone, azithromycin, ciprofloxacin, and penicillin. Isolates were previously collected as part of the Australian Gonococcal Surveillance Programme between Jan 1, 2008, and Dec 31, 2019. All cultured N gonorrhoeae isolates with susceptibility data to all four antimicrobials were included. However, only one isolate was included if several isolates originated from the same individual within 13 days of the previous isolate originating from that individual, and there were less than two standard double-dilution minimum inhibitory concentrations between the isolates. We assessed the use of different combinations of hypothetical antimicrobial susceptibility assays and treatment combinations in terms of their ability to minimise overall ceftriaxone use, and use specifically in isolates with decreased susceptibility to ceftriaxone, compared with standard non-assay-guided empirical ceftriaxone treatment. Findings: We included 23 089 N gonorrhoeae isolates. The prevalence of antimicrobial sensitivity fluctuated significantly during the study. Isolates with decreased susceptibility to ceftriaxone were more likely to be resistant to one or more antimicrobials than isolates without decreased susceptibility (782 [98·6%] of 793 vs 10 661 [47·8%] of 22 296), particularly ciprofloxacin (p<0·0001) and penicillin (p<0·0001). Compared with empirical ceftriaxone treatment, we estimated that strategies based on the use of hypothetical antimicrobial susceptibility would reduce ceftriaxone use (p<0·0001). However, because of co-resistance, most assay-directed treatment strategies, including those involving use of assays for two antibiotics, would result in only moderate reductions in ceftriaxone use among isolates with decreased susceptibility to ceftriaxone. Interpretation: Individualised treatment guided by molecular antimicrobial susceptibility diagnostics could help to reduce overall ceftriaxone use in gonorrhoea. However, the use of these assays needs to be informed by the non-random nature of co-resistance among circulating N gonorrhoeae strains. Funding: Australian Government and Queensland Government.Full Tex
Histo-blood group antigens and rotavirus vaccine virus shedding in Australian infants
No full textRotavirus vaccine performance varies between high and low income countries. One possible explanation is inherited histo-blood group antigens (HBGAs) the expression of which differs between populations. HBGAs are polymorphic glycans on mucosal surfaces. Their presence indicates the secretor phenotype, while their absence identifies a non-secretor status. HBGAs can act as rotavirus receptors and might influence live-attenuated rotavirus vaccine virus replication and shedding. Studies in low and middle income countries of the human rotavirus vaccine Rotarix (RV1), suggest HBGA secretor phenotype is important for vaccine immunogenicity. We investigated in a high income country the association between HBGA phenotype (secretor and Lewis) and the bovine-human reassortment vaccine RotaTeq (RV5) vaccine shedding in the stools of infants following each vaccine dose. Eighty-two infants from an Australian birth cohort provided saliva and weekly stool samples after RV5 vaccination doses. Lewis and secretor HBGA phenotyping was identified from saliva samples and confirmed by genotyping. Vaccine virus strains were detected by real-time polymerase chain reaction assays. No significant association between secretor status and vaccine virus shedding was identified. The proportion of infants who shed rotavirus following the first RV5 dose for secretor and non-secretor infants was 57/64 (89%) and 17/18 (94%), respectively, decreasing to 24/64 (33%) and 9/18 (50%) after the second dose and 26/64 (42%) and 8/18 (44%) following the third vaccine dose, respectively. Similarly, no significant differences were observed in vaccine virus shedding by Lewis, or combined Lewis and secretor status, after each vaccine dose. We found HBGAs were not associated with RV5 vaccine virus shedding in Australian infants.Full Tex
Entanglement and quantity in quantum space - About quantum measurement (II)
No full textAs a continuation and extension of "quantity in phase space" "quantity in quantum space" is introduced. With that, the disappearing of quantum interference discussed in a previous paper [S. Durr, et al., Nature 395 (1998) 33] is explained in the same spirit as our recent papers [Ren De-Ming, Commun. Theor. Phys. (Beijing, China) 41 (2004) 685, 833].Physics, MultidisciplinarySCI(E)中国科学引文数据库(CSCD)1ARTICLE133-364
Sneutrino DM in the NMSSM with inverse seesaw mechanism
No full textIn supersymmetric theories like the Next-to-Minimal Supersymmetric Standard Model (NMSSM), the lightest neutralino with bino or singlino as its dominant component is customarily taken as dark matter (DM) candidate. Since light Higgsinos favored by naturalness can strength the couplings of the DM and thus enhance the DM-nucleon scattering rate, the tension between naturalness and DM direct detection results becomes more and more acute with the improved experimental sensitivity. In this work, we extend the NMSSM by inverse seesaw mechanism to generate neutrino mass, and show that in certain parameter space the lightest sneutrino may act as a viable DM candidate, i.e. it can annihilate by multi-channels to get correct relic density and meanwhile satisfy all experimental constraints. The most striking feature of the extension is that the DM-nucleon scattering rate can be naturally below its current experimental bounds regardless of the higgsino mass, and hence it alleviates the tension between naturalness and DM experiments. Other interesting features include that the Higgs phenomenology becomes much richer than that of the original NMSSM due to the relaxed constraints from DM physics and also due to the presence of extra neutrinos, and that the signatures of sparticles at colliders are quite different from those with neutralino as DM candidate.National Natural Science Foundation of China (NNSFC) [11575053]SCI(E)ARTICLE1
Classical mechanics and quantum mechanics
No full textThe Newton equation of motion is derived from quantum mechanics.Physics, MultidisciplinarySCI(E)中国科学引文数据库(CSCD)2ARTICLE5685-6884
False-negative Chlamydia polymerase chain reaction result caused by a cryptic plasmid-deficient Chlamydia trachomatis strain in Australia
No full textBackground: The 7.5-kb chlamydial cryptic plasmid remains a widely used sequence target for Chlamydia trachomatis nucleic acid amplification tests, but sequence variation in this plasmid, particularly a previously reported 377-bp deletion, can cause false-negative results. Here we report the presence in Australia of a C. trachomatis strain lacking the cryptic plasmid. Methods: A rectal swab from a male in his 50s provided a positive result for C. trachomatis using the Roche Cobas 4800 test, but a negative result in our confirmatory in-house polymerase chain reaction (PCR) method targeting the chlamydial cryptic plasmid. This result was unexpected given our in-house PCR assay targeted a region of sequence outside the recognised 377-bp deletion. To further investigate this discrepancy, the sample was retested using a second in-house PCR targeting a chromosomal (ompA) gene as well as six primer sets flanking various regions of the cryptic plasmid. Results: The sample provided positive results in the second in-house method, confirming the presence of C. trachomatis DNA. All other primer sets targeting the cryptic plasmid failed to amplify, indicating a lack of the chlamydial cryptic plasmid in this sample. Conclusions: The recognition of a plasmid-deficient strain of C. trachomatis within Australia highlights further limitations of using the chlamydial cryptic plasmid for C. trachomatis diagnostics and re-emphasises the benefits of using multitarget assays to avoid false-negative results
Policy-driven Data Sharing over Attribute-Based Encryption supporting Dual Membership
No full textAttribute-Based Encryption (ABE) plays an important role in current secure data sharing through fine-grained customizable policies. However, the existing ABE schemes only support simple predicates, = and ≠, but cannot express a more general membership predicates, ∈ and ∉, in policies. The low expressivity of ABE will enlarge the ciphertext storage and reduce the communication efficiency. To overcome this problem, we propose an ABE supporting Dual Membership (DM-ABE). The core problem for implementing this scheme is how to use cryptographic methods to decide the membership between the verified element and the given set. In order to solve this problem, we design a cryptographic algorithm, called Secure Decision of Membership (SDM), based on aggregation functions. In this algorithm, any set can be aggregated into one cryptographic element, and the verified element and the given set can be converted into another cryptographic element in decision process. The membership between them can be decided by the above two cryptographic elements. Furthermore, we construct the DM-ABE by using SDM. Because of the good expressivity of our DM-ABE, we further propose a novel cryptographic data sharing framework by integrating DM-ABE and attribute-based access control to provide fine-grained access control and security protection for private data. In the security proof of DM-ABE, we prove that the DM-ABE satisfies the semantic security against chosen-plaintext attacks under the DBDHE assumption in the standard model through a unified way, considering both two encryption methods for ∈ and ∉ at the same time. Finally, we analyze our scheme in terms of time and space complexity, and compare it with some existing schemes. The results show that our DM-ABE has a better expressive ability on the boolean logic of general membership predicates, ∈ and ∉.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Cyber Securit
Mycoplasma genitalium infections can comprise a mixture of both fluoroquinolone-susceptible and fluoroquinolone-resistant strains
No full textBACKGROUND: Mycoplasma genitalium was recently added to the CDC's antimicrobial resistance threats 'watch list', as it has rapidly become resistant to mainstay treatments. In Australia, treatment failure with fluoroquinolones remain commonplace, even when Sanger sequencing fails to identify evidence of resistance mutations. METHODS: Suspecting that Sanger sequencing may miss low-load mixed infections, we applied three additional PCR-based approaches (allele-specific primer-based PCR, probe-based PCR and amplicon deep sequencing) to detect mutations associated with fluoroquinolone susceptibility/resistance. We focused on resistance mutations at amino acid positions 83 and 87 of parC, as these were previously shown to be common in Australia. RESULTS: Our results showed evidence of mixtures of fluoroquinolone-susceptible and -resistant strains in up to 27/423 samples (6.4%). These included 1 sample that was indicated to be mixed by Sanger sequencing and all three additional PCR methods, 6 samples detected by two or more of the additional PCRs but not by Sanger sequencing and finally 20 samples that were detected by only one of the additional PCR methods. A key question was whether Sanger sequencing failed to detect fluoroquinolone resistance in any samples; overall, we observed that Sanger sequencing failed to detect fluoroquinolone resistance in up to 3.8% (16/423) of samples. CONCLUSIONS: The presence of mixed susceptibility infections may have important implications for clinical patient management and stresses the need for appropriate detection of resistance and selection of antimicrobials to ensure appropriate treatment of M. genitalium infections.No Full Tex
Constraining the Inner Galactic DM Density Profile with H.E.S.S.
No full text© 2024 by the author. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).In this short review, corresponding to a talk given at the conference “Cosmology 2023 in Miramare”, we combine an analysis of five regions observed by H.E.S.S. in the Galactic Center, intending to constrain the Dark Matter (DM) density profile in a WIMP annihilation scenario. For the analysis, we include the state-of-the-art Galactic diffuse emission Gamma-optimized model computed with DRAGON and a wide range of DM density profiles from cored to cuspy profiles, including different kinds of DM spikes. Our results are able to constrain generalized NFW profiles with an inner slope ≳1.3 . When considering DM spikes, the adiabatic spike is completely ruled out. However, smoother spikes given by the interactions with the bulge stars are compatible if ≲0.8 , with an internal slope of sp-stars=1.5.This work has been supported by the grants PID2021-125331NB-I00, PID2022-139841NB-I00, and CEX2020-001007-S, funded by MCIN/AEI/10.13039/501100011033, by “ERDF A way of making Europe”, and the MULTIDARK Project RED2022-134411-T. The author’s contribution to this work has been supported by the FPI Severo Ochoa PRE2021-099137 grant.With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2020-001007-S).Peer reviewe
Diabetes mellitus (DM) related lower extremity amputations (LEA) rate and risk factors.
No full textAuthor: Ieva Vasiliūtė Title: Diabetes mellitus (DM) related lower extremity amputations (LEA) rate and risk factors. Aim: To investigate LEA rate and risk factors in patients with DM. Objectives: To evaluate DM related LEA rate. To determine DM related LEAs levels and patients demographic factors relation. To determine DM related LEAs levels and type of DM relation. To determine DM related LEAs levels and DM duration, body mass index (BMI), glycated hemoglobin (HbA1c) meanings relation. To evaluate expected mathematically based risk factors. Methods: Retrospective medical records study of 153 patients with DM, who underwent LEAs at the Hospital of Lithuanian University of Health Sciences Kaunas clinics was performed during the 2012 01 01 – 2014 12 31 period. Statistical analysis was performed using the standard SPSS 20.0 program. Results: 33,33% of legs amputations occured among people with DM and 66,67% of them were male (p<0,001). Major LEAs were performed mostly in patients with type 2 DM (86,96%) than those with type 1 DM (p<0,001). Male patients LEAs were performed in patients suffering for shorter duration of DM than in women (19,18 m. (±95% PI 16,71-21,65) vs. 23,36 m. (±95% PI 20,07-26,65), p=0,053). Patients with type 2 DM underwent LEAs had DM for shorter durations (16,19 m. (±95% PI 14,32-18,06)) than those with type 1 DM patients (31,43 m. (±95% PI 28,40-34,45)) ( p<0,001). Major LEAs remove patients had BMI (32,86±5,55 kg/m2) than minor LEAs remove patients (29,13±5,91 kg/m2) (p=0,027). No significant relation was found with amputation level and HbA1c average (p=0,246). DM related eye damage increases the risk of minor LEAs 3,10 times (p=0,001). Obesity/overweight the risk of major LEAs increases 5,65 times (p=0,036) and 2,56 times with obliterate atherosclerosis (p=0,006). Patients with type 2 DM have a 3,2 times (p=0,002) higher risk of undergoing major LEA. Conclusions: A third of patients who had undergone LEAs had DM. Amputations were carried out more frequently in men. DKA arose more often in patients with type 2 DM. LEAs were performed a shorter duration male DM patients. Type 2 DM patients suffered LEAs nearly 2 times shorter duration. Major LEAs experienced patients had a higher BMI. The average of HbA1c is not significantly related with amputation levels. DM related eye damage increases the minor LEAs risk by 3,10 times. Obesity/being overweight increases the risk of major LEAs 5,65 times, obliterate atherosclerosis - 2,56 times. Patients with type 2 DM have a 3,2 times higher risk of major LEA
- …
