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The environmental fate and biological effects of nanomaterials in marine ecosystems are of increasing concern, yet monitoring techniques remain limited. This study explores alternative methods to evaluate the influence of Gold Nanoparticles (AuNPs) on corals using Gorgonia ventalina as a model organism. Through energy dispersive X-ray spectroscopy (EDAX), we traced AuNP accumulation within coral tissues. Raman spectroscopy revealed an elevation in polyene content, signifying a stress response attributable to nanoparticle exposure. Furthermore, Fourier transform infrared spectroscopy demonstrated a reduction in calcium levels, while the Bradford assay indicated a decrease in protein concentration, suggesting a disruption in the calcification process vital to coral health. These findings highlight the utility of these alternative analytical techniques in providing comprehensive insights into the effects of nanomaterials on corals. The integration of these methods offers a more robust framework for environmental monitoring, with the potential to inform conservation strategies for marine ecosystems amid growing nanoparticle use

Shiga toxin-producing Escherichia coli are zoonotic pathogens that cause food-borne human disease. Among these, the O157:H7 serotype has evolved from an enteropathogenic O55:H7 ancestor through the displacement of the somatic gene cluster and recurrent toxigenic conversion by Shiga toxin-converting bacteriophages. However, atypical strains that lack the Shiga toxin, the characteristic virulence hallmark, are circulating in this lineage. For this study, we analyzed the pathogenome and virulence inventories of the stx+ strain, TT12A, isolated from a patient with hemorrhagic colitis, and its respective co-isolated stx− strain, TT12B. Sequencing the genomes to closure proved critical to the cataloguing of subtle strain differentiating sequence and structural polymorphisms at a high-level of phylogenetic accuracy and resolution. Phylogenomic profiling revealed SNP and MLST profiles similar to the near clonal outbreak isolates. Their prophage inventories, however, were notably different. The attenuated atypical non-shigatoxigenic status of TT12B is explained by the absence of both the ΦStx1a- and ΦStx2a-prophages carried by TT12A, and we also recorded further alterations in the non-Stx prophage complement. Phenotypic characterization indicated that culture growth was directly impacted by the strains’ distinct lytic phage complement. Altogether, our phylogenomic and phenotypic analyses show that these intimately related isogenic strains are on divergent Stx(+/stx−) evolutionary paths.

The toxigenic conversion of Escherichia coli strains by Shiga toxin-converting (Stx) bacteriophages were prominent and recurring events in the stepwise evolution of enterohemorrhagic E. coli (EHEC) O157:H7 from an enteropathogenic (EPEC) O55:H7 ancestor. Atypical, attenuated isolates have been described for both non-sorbitol fermenting (NSF) O157:H7 and SF O157:NM serotypes, which are distinguished by the absence of Stx, the characteristic virulence hallmark of Stx-producing E. coli (STEC). Such atypical isolates either never acquired Stx-phages or may have secondarily lost stx during the course of infection, isolation, or routine subculture; the latter are commonly referred to as LST (Lost Shiga Toxin)-isolates. In this study we analyzed the genomes of 15 NSF O157:H7 and SF O157:NM strains from North America, Europe, and Asia that are characterized by the absence of stx, the virulence hallmark of STEC. The individual genomic basis of the Stx (−) phenotype has remained largely undetermined as the majority of STEC genomes in public genome repositories were generated using short read technology and are in draft stage, posing a major obstacle for the high-resolution whole genome sequence typing (WGST). The application of LRT (long-read technology) sequencing provided us with closed genomes, which proved critical to put the atypical non-shigatoxigenic NSF O157:H7 and SF O157:NM strains into the phylogenomic context of the stepwise evolutionary model. Availability of closed chromosomes for representative Stx (−) NSF O157:H7 and SF O157:NM strains allowed to describe the genomic basis and individual evolutionary trajectories underlying the absence of Stx at high accuracy and resolution. The ability of LRT to recover and accurately assemble plasmids revealed a strong correlation between the strains’ featured plasmid genotype and chromosomally inferred clade, which suggests the coevolution of the chromosome and accessory plasmids. The identified ancestral traits in the pSFO157 plasmid of NSF O157:H7 strain LSU-61 provided additional evidence for its intermediate status. Taken together, these observations highlight the utility of LRTs for advancing our understanding of EHEC O157:H7/NM pathogenome evolution. Insights into the genomic and phenotypic plasticity of STEC on a lineage- and genome-wide scale are foundational to improve and inform risk assessment, biosurveillance, and prevention strategies.

Abstract Background No studies have measured preference-based utility weights for specific toxicities and outcomes associated with approved and investigational adjuvant treatments for patients with resected high-risk melanoma. Methods A cross-sectional study was conducted in the United Kingdom and Australia to obtain utilities for 14 adjuvant melanoma health states. One-on-one interviews were conducted using standard gamble; utility weights range from 0.0, dead, to 1.0, full health. Supplemental risk questions also were asked. Results Among 155 participants (52% male; mean age, 46 years) “adjuvant treatment no toxicities” (0.89) was most preferred, followed by “induction treatment” (0.88), and “no treatment” (0.86). Participants least preferred “cancer recurrence” (0.62); the utility for “cancer recurrence and 10-year survival with treatment” was 0.70. Disutilities for grade 2 toxicities ranged from −0.06 for fatigue to −0.13 for hypophysitis. The mean maximum acceptable risk of a life-threatening event ranged from 30% for a 6% increase in the chance of remaining cancer free over 3 years to 40% for an 18% increase; Australian respondents were willing to take higher risks. Conclusion Reproducible health utilities for adjuvant melanoma health states were obtained from the general population in two countries. These utilities can be incorporated into treatment-specific cost-effectiveness evaluations.

We report studies of the surface fringe structures and tunable bandgap width of atomic-thin boron nitride nanosheets (BNNSs). BNNSs are synthesized by using digitally controlled pulse deposition techniques. The nanoscale morphologies of BNNSs are characterized by using scanning electron microscope (SEM), and transmission electron microscopy (TEM). In general, the BNNSs appear microscopically flat in the case of low temperature synthesis, whereas at high temperature conditions, it yields various curved structures. Experimental data reveal the evolutions of fringe structures. Functionalization of the BNNSs is completed with hydrogen plasma beam source in order to efficiently control bandgap width. The characterizations are based on Raman scattering spectroscopy, X-ray diffraction (XRD), and FTIR transmittance spectra. Red shifts of spectral lines are clearly visible after the functionalization, indicating the bandgap width of the BNNSs has been changed. However, simple treatments with hydrogen gas do not affect the bandgap width of the BNNSs.

Conducting composite films containing carbon nanotubes (CNTs) were prepared by using the biopolymer kappa-carrageenan (KC) as a dispersant. Rheological studies indicated that 0.5% w/v was the appropriate KC concentration for dispersing CNTs. Our results showed that multiwalled nanotubes (MWNTs) required less sonic energy than single-walled nanotubes (SWNTs) for the dispersion process to be complete. Films prepared by vacuum filtration exhibited higher conductivity and improved mechanical characteristics compared to those prepared by evaporative casting. All composite films displayed sensitivity to water vapour, but MWNT films were more sensitive than SWNT films.

High-quality two-dimensional (2D) crystalline boron nitride nanosheets (BNNSs) were grown on silicon wafers by using pulsed plasma beam deposition techniques. Self-powered deep ultraviolet (DUV) photodetectors (PDs) based on BNNSs with Schottky contact structures are designed and fabricated. By connecting the fabricated DUV photodetector to an ammeter, the response strength, response time and recovery time to different DUV wavelengths at different intensities have been characterized using the output short circuit photocurrent without a power supply. Furthermore, effects of temperature and plasma treatment on the induced photocurrent response of detectors have also been investigated. The experimental data clearly indicate that plasma treatment would significantly improve both induced photocurrent and response time. The BNNS-based DUV photodetector is demonstrated to possess excellent performance at a temperature up to 400 °C, including high sensitivity, high signal-to-noise ratio, high spectral selectivity, high speed, and high stability, which is better than almost all reported semiconducting nanomaterial-based self-powered photodetectors.

Escherichia coli serotype O157:H7 was only recognized as a human pathogen a little more than a decade ago, yet it has become a major foodborne pathogen. In the United States, the severity of serotype O157:H7 infections in the young and the elderly has had a tremendous impact on human health, the food industry, and federal regulations regarding food safety. The implication of acidic foods as vehicles of infection has dispelled the concept that low-pH foods are safe. Further, the association of nonbovine products with outbreaks suggests that other vehicles of transmission may exist for this pathogen. In laboratory diagnosis, most microbiologic assays rely on a single phenotype to selectively isolate this pathogen. However, the increasing evidence that phenotypic variations exist among isolates in this serogroup may eventually necessitate modifications in assay procedures to detect them.

We report a case of unilateral serous choroidal effusion in a patient without prior glaucoma surgeries that developed within 1week of starting topical dorzolamide. A Caucasian female in her 60s with a history of severe primary open-angle glaucoma in the left eye without prior glaucoma surgeries developed irritation and subsequently blurry vision in her left eye within 1week of starting topical dorzolamide 2% in the left eye only. Funduscopic exam and B-scan ultrasound demonstrated a serous choroidal effusion in the nasal and temporal periphery. After discontinuing dorzolamide and initiating prednisolone and cycloplegic agents, the choroidal effusions fully resolved after 2 weeks, and vision returned to baseline. Choroidal effusion can occur as a result of an idiosyncratic reaction to topical dorzolamide even in patients without prior glaucoma surgeries. Immediate cessation of dorzolamide and treatment with steroid and cycloplegic agents result in good vision recovery for dorzolamide-induced choroidal effusion. [ABSTRACT FROM AUTHOR]

Patients with relapsed/refractory multiple myeloma (RRMM) resistant to multiple drug classes remain a high unmet need population. This longitudinal retrospective cohort study assessed real-world treatment patterns and outcomes in adults with RRMM. Patients who had three or more prior lines of therapy including a proteasome inhibitor (PI) and an immunomodulatory agent (double-exposed) were further categorized as refractory to a PI and an immunomodulatory agent (double-class refractory, n = 381) or additionally to an anti-CD38 monoclonal antibody (triple-class refractory, n = 173). Treatment options are limited for patients with double-class or triple-class refractory disease. Retreatment is a part of standard of care. Bortezomib and lenalidomide had the highest retreatment rates among double-class and triple-class refractory patients. Survival outcomes remain poor among RRMM patients with median overall survival (OS) of 22.3 and 11.6 months for double-class refractory and triple-class refractory patients, respectively. This study highlights the need for novel efficacious therapies in this heavily pretreated RRMM population. [ABSTRACT FROM AUTHOR]