Colorectal Cancer in Australian Young Adults

Purpose of Review: Although the overall incidence and mortality rates of colorectal cancer (CRC) have been decreasing in Australia over the last 20 years, there has been a significant increase in the incidence of early-onset CRC (EOCRC) without a clear explanation. In this review, we have outlined the epidemiology, suggested risk factors, clinicopathological and molecular features, survival and prognosis, and treatment approach for Australian young adults with CRC. Recent findings: There has been a shift in the epidemiology of bowel cancer incidence and mortality across different age groups, and there are clinicopathological and molecular feature differences between EOCRC and late onset CRC (LOCRC). EOCRC is more common in the distal colon and rectum. Young patients are diagnosed at more advanced stages of the disease with increased prevalence of aggressive pathologic features and tend to receive more aggressive chemotherapies. EOCRC patients present with a predominance of symptoms in the left side of the colon, and importantly, cases do not have clinically known risk factors. The microbiota may play a significant role in the CRC pathogenesis through an impact on host metabolism and through the transmission of metabolic and even CRC risk in non-Mendelian familial aggregation. Summary: The increase in the incidence and mortality rates of young adults with CRC has been significant. Thus, more collaborative research is needed to explain the reasons behind the increase in CRC incidence, and to identify young adults in the population at an increased risk of developing CRC at an early age.Reger R. Mikaeel, Timothy J. Price, Eric Smith, Paul A. Drew, Wendy Uylaki, Mehgan Horsnell, Joanne P. Youn

Redefining Clostridioides difficile infection antibiotic response and clinical outcomes

With the approval and development of narrow-spectrum antibiotics for the treatment of Clostridioides difficile infection (CDI), the primary endpoint for treatment success of CDI antibiotic treatment trials has shifted from treatment response at end of therapy to sustained response 30 days after completed therapy. The current definition of a successful response to treatment (three or fewer unformed bowel movements [UBMs] per day for 1-2 days) has not been validated, does not reflect CDI management, and could impair assessments for successful treatment at 30 days. We propose new definitions to optimise trial design to assess sustained response. Primarily, we suggest that the initial response at the end of treatment be defined as (1) three or fewer UBMs per day, (2) a reduction in UBMs of more than 50% per day, (3) a decrease in stool volume of more than 75% for those with ostomy, or (4) attainment of bowel movements of Bristol Stool Form Scale types 1-4, on average, by day 2 after completion of primary CDI therapy (ie, assessed on day 11 and day 12 of a 10-day treatment course) and following an investigator determination that CDI treatment can be ceased.Molecular basis of bacterial pathogenesis, virulence factors and antibiotic resistanc

Diving into the vertical dimension of elasmobranch movement ecology

Knowledge of the three-dimensional movement patterns of elasmobranchs is vital to understand their ecological roles and exposure to anthropogenic pressures. To date, comparative studies among species at global scales have mostly focused on horizontal movements. Our study addresses the knowledge gap of vertical movements by compiling the first global synthesis of vertical habitat use by elasmobranchs from data obtained by deployment of 989 biotelemetry tags on 38 elasmobranch species. Elasmobranchs displayed high intra- and interspecific variability in vertical movement patterns. Substantial vertical overlap was observed for many epipelagic elasmobranchs, indicating an increased likelihood to display spatial overlap, biologically interact, and share similar risk to anthropogenic threats that vary on a vertical gradient. We highlight the critical next steps toward incorporating vertical movement into global management and monitoring strategies for elasmobranchs, emphasizing the need to address geographic and taxonomic biases in deployments and to concurrently consider both horizontal and vertical movements

Polarimetric line profiles for scattering off rotating disks

Peer reviewe

Linear Line Polarimetry Modelling of Pre-main Sequence Stars

Original paper can be found at: http://www.aspbooks.org/ Copyright ASPWe present emission line polarimetry data and modelling relevant to the circumstellar geometry and kinematics around pre-main sequence stars. For a sample of both Herbig Ae/Be stars and T Tauri stars, we find that most show polarization changes across H®, implying that flattened structures are common on the smallest scales { and over a range of stellar masses. We also present Monte Carlo calculations of spectral line profiles scattered in rotating accretion disks. We consider the case of a central star that emits line photons uniformly, as well as via hot spots. Intriguingly, the switch between a uniform point source and a finite-sized star results in a marked difference in the position angle variation across the line. Our models demonstrate the diagnostic potential of line polarimetry in determining the disk inclination and the size of the inner hole { a spatial scale no other technique currently accesses

Linear Spectropolarimetry of Young and Other Emission Line Stars

Peer reviewe