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As part of its pathogenesis, Salmonella enterica serovar Typhimurium delivers effector proteins into host cells. One effector is SspH2, a member of the so-called novel E3 ubiquitin ligase family, that interacts with and enhances, NOD1 pro-inflammatory signaling, though the underlying mechanisms are unclear. Here, we report that SspH2 interacts with multiple members of the NLRC family to enhance pro-inflammatory signaling by targeted ubiquitination. We show that SspH2 modulates host innate immunity by interacting with both NOD1 and NOD2 in mammalian epithelial cell culture via the NF-κB pathway. Moreover, purified SspH2 and NOD1 directly interact, where NOD1 potentiates SspH2 E3 ubiquitin ligase activity. Mass spectrometry and mutational analyses identified four key lysine residues in NOD1 that are required for its enhanced activation by SspH2, but not its basal activity. These critical lysine residues are positioned in the same region of NOD1 and define a surface on the receptor that appears to be targeted by SspH2. Overall, this work provides evidence for post-translational modification of NOD1 by ubiquitin and uncovers a unique mechanism of spatially selective ubiquitination to enhance the activation of an archetypal NLR.

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Radiation therapy (RT) is a critical component of multidisciplinary cancer care, but has inconsistent curricular exposure. We characterize the radiation oncology (RO) content on the standardized undergraduate medical examinations by comparing its context and prevalence with other domains in oncology. National Board of Medical Examiners (NBME) self-assessments and sample questions for the United States Medical Licensing Exam (USMLE) Steps 1-3 and NBME clinical science shelf examinations were accessed (n = 3878). Questions were inductively analyzed for content pertaining to oncology and treatment modalities of RT, systemic therapy (ST), and surgical intervention (SI). Questions were coded using USMLE Physician Tasks/Competencies and thematic analysis. Descriptive statistics and analyses using the Kruskal-Wallis test are reported. A total of 337 questions (8.6%) within the USMLE and shelf exams included oncology content, with 101 questions (2.6%) referencing at least one cancer treatment modality (n = 35 RT, 45 ST, 57 SI). Treatment questions were more common on USMLE Step 2 CK (n = 35/101, 32%) compared to Step 1 (n = 23/101, 23%) and Step 3 (n = 8/101, 8%) (p < 0.001). RT was significantly less likely to be the correct answer (2/35, 6%) compared to ST (4/45, 9%) and SI (18/57, 32%) (p = 0.003). Therapeutic oncology questions are uncommon on the examination material, with an under-representation of radiation-related content, and contextual bias favoring surgical approaches. We advocate for greater RO involvement in the content creation of such examinations to help trainees better understand multidisciplinary cancer care.

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PURPOSE OF REVIEW: The goal is to describe the evolution of radiation therapy (RT) utilization in the management of localized and metastatic prostate cancer. RECENT FINDINGS: Long term data for a variety of hypofractionated definitive RT dose-fractionation schemes has matured, allowing patients and providers many standard-of-care options to choose from. Post-prostatectomy, adjuvant RT has largely been replaced by an early salvage approach. Multiparametric MRI and PSMA PET have enabled increasingly targeted RT delivery to the prostate and oligometastatic tumors. Areas of active investigation include determining the value of proton beam therapy and perirectal spacers, and optimally incorporate genomic tumor profiling and next generation hormonal therapies with RT in the curative setting. The use of radiation therapy to treat prostate cancer is rapidly evolving. In the coming years, there will be continued improvements in a variety of areas to enhance the value of RT in multidisciplinary prostate cancer management.

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The mono(2-hydroxyethyl) terephthalate hydrolase (MHETase) from Ideonella sakaiensis carries out the second step in the enzymatic depolymerization of poly(ethylene terephthalate) (PET) plastic into the monomers terephthalic acid (TPA) and ethylene glycol (EG). Despite its potential industrial and environmental applications, poor recombinant expression of MHETase has been an obstacle to its industrial application. To overcome this barrier, we developed an assay allowing for the medium-throughput quantification of MHETase activity in cell lysates and whole-cell suspensions, which allowed us to screen a library of engineered variants. Using consensus design, we generated several improved variants that exhibit over 10-fold greater whole-cell activity than wild-type (WT) MHETase. This is revealed to be largely due to increased soluble expression, which biochemical and structural analysis indicates is due to improved protein folding.

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Parasites, such as the malaria parasite P. falciparum, are critically dependent on host nutrients. Interference with nutrient uptake can lead to parasite death and, therefore, serve as a successful treatment strategy. P. falciparum parasites cannot synthesise cholesterol, and instead source this lipid from the host. Here, we tested whether cholesterol uptake pathways could be 'hijacked' for optimal drug delivery to the intracellular parasite. We found that fluorescent cholesterol analogues were delivered from the extracellular environment to the intracellular parasite. We investigated the uptake and inhibitory effects of conjugate compounds, where proven antimalarial drugs (primaquine and artesunate) were attached to steroids that mimic the structure of cholesterol. These conjugated antimalarial drugs improved the inhibitory effects against multiple parasite lifecycle stages, multiple parasite species, and drug-resistant parasites, whilst also lowering the toxicity to human host cells. Steroids with introduced peroxides also displayed antimalarial activity. These results provide a proof-of-concept that cholesterol mimics can be developed as a drug delivery system against apicomplexan parasites with the potential to improve drug efficacy, increase therapeutic index, and defeat drug resistance.

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Large ensembles of global temperature are provided for three climate scenarios: historical (2006-16), 1.5 °C and 2.0 °C above pre-industrial levels. Each scenario has 700 members (70 simulations per year for ten years) of 6-hourly mean temperatures at a resolution of 0.833° ´ 0.556° (longitude ´ latitude) over the land surface. The data was generated using the climateprediction.net (CPDN) climate simulation environment, to run HadAM4 Atmosphere-only General Circulation Model (AGCM) from the UK Met Office Hadley Centre. Biases in simulated temperature were identified and corrected using quantile mapping with reference temperature data from ERA5. The data is stored within the UK Natural and Environmental Research Council Centre for Environmental Data Analysis repository as NetCDF V4 files.

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Cardiopulmonary bypass (CPB) can alter pharmacokinetic (PK) parameters and the drug may adsorb to the CPB device, altering exposure. Cefazolin is a beta-lactam antibiotic used for antimicrobial prophylaxis during cardiac surgery supported by CPB. Adsorption of cefazolin could result in therapeutic failure. An ex vivo study was undertaken using CPB devices primed and then dosed with cefazolin and samples were obtained over 1 hour of recirculation. Twelve experimental runs were conducted using different CPB device sizes (neonate, infant, child, and adult), device coatings (Xcoating™, Rheoparin®, PH.I.S.I.O), and priming solutions. The time course of saturable binding, using Bmax (binding capacity), Kd (dissociation constant), and T2off (half-time of dissociation), described cefazolin adsorption. Bmax estimates for the device sizes were neonate 40.0 mg (95% CI 24.3, 67.4), infant 48.6 mg (95% CI 5.97, 80.2), child 77.8 mg (95% CI 54.9, 103), and adult 196 mg (95% CI 191, 199). The Xcoating™ Kd estimate was 139 mg/L (95% CI 27.0, 283) and the T2off estimate was 98.4 min (95% CI 66.8, 129). The Rheoparin® and PH.I.S.I.O coatings had similar binding parameters with Kd and T2off estimates of 0.169 mg/L (95% CI 0.01, 1.99) and 4.94 min (95% CI 0.17, 59.4). The Bmax was small (< 10%) relative to a typical total patient dose during cardiac surgery supported by CPB. A dose adjustment for cefazolin based solely on drug adsorption is not required. This framework could be extended to other PK studies involving CPB.

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Importance: The Cluster Randomized Trial of PSA Testing for Prostate Cancer (CAP) reported no effect of prostate-specific antigen (PSA) screening on prostate cancer mortality at a median 10-year follow-up (primary outcome), but the long-term effects of PSA screening on prostate cancer mortality remain unclear. Objective: To evaluate the effect of a single invitation for PSA screening on prostate cancer-specific mortality at a median 15-year follow-up compared with no invitation for screening. Design, Setting, and Participants: This secondary analysis of the CAP randomized clinical trial included men aged 50 to 69 years identified at 573 primary care practices in England and Wales. Primary care practices were randomized between September 25, 2001, and August 24, 2007, and men were enrolled between January 8, 2002, and January 20, 2009. Follow-up was completed on March 31, 2021. Intervention: Men received a single invitation for a PSA screening test with subsequent diagnostic tests if the PSA level was 3.0 ng/mL or higher. The control group received standard practice (no invitation). Main Outcomes and Measures: The primary outcome was reported previously. Of 8 prespecified secondary outcomes, results of 4 were reported previously. The 4 remaining prespecified secondary outcomes at 15-year follow-up were prostate cancer-specific mortality, all-cause mortality, and prostate cancer stage and Gleason grade at diagnosis. Results: Of 415 357 eligible men (mean [SD] age, 59.0 [5.6] years), 98% were included in these analyses. Overall, 12 013 and 12 958 men with a prostate cancer diagnosis were in the intervention and control groups, respectively (15-year cumulative risk, 7.08% [95% CI, 6.95%-7.21%] and 6.94% [95% CI, 6.82%-7.06%], respectively). At a median 15-year follow-up, 1199 men in the intervention group (0.69% [95% CI, 0.65%-0.73%]) and 1451 men in the control group (0.78% [95% CI, 0.73%-0.82%]) died of prostate cancer (rate ratio [RR], 0.92 [95% CI, 0.85-0.99]; P = .03). Compared with the control, the PSA screening intervention increased detection of low-grade (Gleason score [GS] ≤6: 2.2% vs 1.6%; P < .001) and localized (T1/T2: 3.6% vs 3.1%; P < .001) disease but not intermediate (GS of 7), high-grade (GS ≥8), locally advanced (T3), or distally advanced (T4/N1/M1) tumors. There were 45 084 all-cause deaths in the intervention group (23.2% [95% CI, 23.0%-23.4%]) and 50 336 deaths in the control group (23.3% [95% CI, 23.1%-23.5%]) (RR, 0.97 [95% CI, 0.94-1.01]; P = .11). Eight of the prostate cancer deaths in the intervention group (0.7%) and 7 deaths in the control group (0.5%) were related to a diagnostic biopsy or prostate cancer treatment. Conclusions and Relevance: In this secondary analysis of a randomized clinical trial, a single invitation for PSA screening compared with standard practice without routine screening reduced prostate cancer deaths at a median follow-up of 15 years. However, the absolute reduction in deaths was small. Trial Registration: isrctn.org Identifier: ISRCTN92187251.

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Methionine is an essential amino acid critical for cell growth and survival. Preclinical evidence suggests a methionine restricted diet (MRD) sensitizes cancer to radiation therapy (RT), without significant adverse effects. However, this has never been evaluated in humans. The purpose of this pilot study was to evaluate the safety and feasibility of concurrent MRD with standard-of-care definitive RT in adults with any non-skin cancer malignancy. The MRD extended from 2 wk before RT initiation, through 2 wk beyond RT completion. The primary endpoint of safety was assessed as rate of grade 3 or higher acute and late toxicities. Feasibility was assessed with quantitative plasma amino acid panel every 2 wk during the MRD (target plasma methionine 13 µM). Nine patients were accrued over a two-year period, with five able to complete the treatment course. The trial was closed due to slow accrual and subjects' difficulty maintaining the diet. No grade 3 or higher adverse events were observed. Subjects' average methionine level was 18.8 µM during treatment, with average nadir 16.8 µM. These findings suggest the safety of concurrent MRD with RT, with toxicities comparable to those expected with RT alone. However, the diet was challenging, and unacceptable to most patients.

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Purpose: Medical student access to radiation oncology (RO) research opportunities is important for stimulating interest in the specialty. The purpose of this study was to assess the publication record during medical school of students who ultimately matched in RO, to characterize the source(s) of their RO mentorship relative to other specialties. Methods and Materials: We performed web-based searches to identify manuscripts published during medical school (defined as being published from January 2016 to December 2019) for all RO residents with postgraduate year 2 status in 2020 to 2021. Students with a PhD degree and international graduates were excluded. Characteristics of these publications, the student, and the primary mentor, were assessed. Results: A total of 435 publications were authored by the 148 included residents. In total, 115 (78%) attended a medical school with an affiliated RO residency program. The median number of publications per student was 2 (interquartile range, 1-4), and students' median byline author position was 2 (interquartile range, 1-4). In total, 351 publications (80.7%) were on a cancer-related topic, with 234 (53.8%) published in oncology-oriented journal, and 96 (22.0%) published in RO-oriented journals. There were 294 unique mentors, with 70 mentors (24%) on 2 or more student publications. Most mentors (n = 187, 64%) shared the same institution as the student. Mentors were most commonly radiation oncologists/radiation biologists/medical physicists (n = 153, 52.6%), surgical subspecialists (n = 53, 21%), and medical oncologists (n = 18, 6.2%). Students working with primary RO mentors were more likely to publish in an oncology-oriented journal (79.1% vs 18.2%, P < .01) or RO-oriented journal (36.2% vs 2.2%, P < .01), compared with students working with non-RO mentors, respectively. A higher percentage of publications with RO mentors occurred in the last 2 years of medical school compared with the first 2 years (64.0% vs 40.9%, respectively, P < .01). Conclusions: Approximately one-half of student publications among future RO residents are published in nononcology journals, and result from mentoring relationships with non-RO physicians.

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Purpose: Most medical students have limited exposure to radiation oncology (RO) before deciding which specialty to choose for residency. This may limit the number and diversity of RO applicants. The purpose of this study was to determine students' views on a combined pathway program of RO with internal medicine (IM), as well as other related medical specialties, as a potential means of overcoming barriers to interest in RO and the early decision point to solo training in a highly specialized field. Methods and Materials: In July to August 2022, all 299 United States student and postgraduate year 1 members of the American Society for Radiation Oncology were sent an electronic survey assessing their views on advantages and disadvantages of a combined IM/RO training pathway, and interest in several options of combined pathway programs. Results: Eighty participants completed the survey (response rate 27%). Thirty-four (43%) were very or extremely interested in IM/RO residency (median Likert-type rating 3, IQR 2-4). The most important potential advantages of an IM/RO pathway included greater flexibility in employment options (n = 51, 64%), enhanced general medical knowledge to facilitate ambitions in other career pathways (n = 46, 58%), improved patient care (n = 43, 54%), and having a pathway for combined hematologic/oncology and RO board certification (n = 46, 58%). In comparison to IM/RO, participants were significantly more interested in a combined RO and hematology/oncology program (median Likert-type rating 5, IQR 5-5, P = .005). Among the subgroup of 26 survey participants who believed it less likely they would apply for RO residency, 18 (69%) thought an IM/RO pathway would increase their interest in RO (median Likert-type rating 4, IQR 3-5). Interest in IM/RO did not differ by gender, race, or ethnicity. Conclusions: Combined training pathways involving RO were viewed positively by survey respondents, and may be particularly appealing to those less committed to a career in RO. Further research will help guide recommendations for the creation of these programs.

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Lactate dehydrogenase (LDH) from Schistosoma mansoni has peculiar properties for a eukaryotic LDH. Schistosomal LDH (SmLDH) isolated from schistosomes, and the recombinantly expressed protein, are strongly inhibited by ATP, which is neutralized by fructose-1,6-bisphosphate (FBP). In the conserved FBP/anion binding site we identified two residues in SmLDH (Val187 and Tyr190) that differ from the conserved residues in LDHs of other eukaryotes, but are identical to conserved residues in FBP-sensitive prokaryotic LDHs. Three-dimensional (3D) models were generated to compare the structure of SmLDH with other LDHs. These models indicated that residues Val187, and especially Tyr190, play a crucial role in the interaction of FBP with the anion pocket of SmLDH. These 3D models of SmLDH are also consistent with a competitive model of SmLDH inhibition in which ATP (inhibitor) and FBP (activator) compete for binding in a well-defined anion pocket. The model of bound ATP predicts a distortion of the nearby key catalytic residue His195, resulting in enzyme inhibition. To investigate a possible physiological role of this allosteric regulation of LDH in schistosomes we made a kinetic model in which the allosteric regulation of the glycolytic enzymes can be varied. The model showed that inhibition of LDH by ATP prevents fermentation to lactate in the free-living stages in water and ensures complete oxidation via the Krebs cycle of the endogenous glycogen reserves. This mechanism of allosteric inhibition by ATP prevents the untimely depletion of these glycogen reserves, the only fuel of the free-living cercariae. Neutralization by FBP of this ATP inhibition of LDH prevents accumulation of glycolytic intermediates when S. mansoni schistosomula are confronted with the sudden large increase in glucose availability upon penetration of the final host. It appears that the LDH of S. mansoni is special and well suited to deal with the variations in glucose availability the parasite encounters during its life cycle.

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PURPOSE: To determine medical students' views of various aspects of a career in radiation oncology (RO) to identify areas that may benefit from reform and to guide initiatives to stimulate broader and more diverse student interest in the specialty. METHODS AND MATERIALS: An electronic survey was sent to student oncology interest group members at seven US medical schools. The survey asked students to rate 19 aspects of RO on a 5-point bipolar Likert-type scale. Descriptive statistics are reported, along with subgroup analyses based on participants' demographics. RESULTS: The response rate was 51.1% (n = 275 of 538). The most favorably rated aspects of RO were outpatient working hours (mean ± SD Likert-type rating of 4.51 ± 0.82), routinely working with other physicians (4.45 ± 0.76), and use of advanced technology to treat patients. The most unfavorably rated aspects of RO were less geographic flexibility for residency or employment (1.98 ± 1.04), spending a lot of time on a computer doing treatment planning (2.80 ± 1.21), and having a job that is not well understood by most doctors and the general public (2.89 ± 1.02). Gender was associated with significant differences in 8 of 19 questions in how each aspect of RO was viewed. Few differences were observed based on race or ethnicity, though Asian participants had a significantly more favorable view of RO being a more science-oriented specialty compared with White or underrepresented students, respectively (3.50 versus 3.21 versus 2.84, P = .01). CONCLUSIONS: These findings inform the RO community in the development of more effective initiatives to encourage students to fully explore the specialty.

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Insects are key components of food chains, and monitoring data provides new opportunities to identify trophic relationships at broad spatial and temporal scales. Here, combining two monitoring datasets from Great Britain, we reveal how the population dynamics of the blue tit Cyanistes caeruleus are influenced by the abundance of moths - a core component of their breeding diet. We find that years with increased population growth for blue tits correlate strongly with high moth abundance, but population growth in moths and birds is less well correlated; suggesting moth abundance directly affects bird population change. Next, we identify moths that are important components of blue tit diet, recovering associations to species previously identified as key food sources such as the winter moth Operoptera brumata. Our work provides new evidence that insect abundance impacts bird population dynamics in natural communities and provides insight into spatial diet turnover at a national-scale.

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Drug checking is a harm reduction measure that provides people with the opportunity to confirm the identity and purity of substances before consumption. The CanTEST Health and Drug Checking Service is Australia's first fixed-site drug checking service, where clients can learn about the contents of the samples they provide while receiving tailored harm reduction and health advice. Three samples were recently presented to the service with the expectation of 4-fluoromethylphenidate (4F-MPH) 1, methoxetamine (MXE) 2 and 3-methylmethcathinone (3-MMC) 3. The identity of all three samples did not meet these expectations and remained unknown on-site, as no high confidence identifications were obtained. However, further analysis by nuclear magnetic resonance spectroscopy, high resolution gas chromatography-electron ionisation-mass spectrometry and liquid chromatography-electrospray ionisation-mass spectrometry at the nearby Australian National University allowed for the structure elucidation of the three samples as 4-fluoro-α-pyrrolidinoisohexanophenone (4F-α-PiHP) 4, 1-(4-fluorobenzyl)-4-methylpiperazine (4F-MBZP) 5 and N-propyl-1,2-diphenylethylamine (propylphenidine) 6, respectively. Given all three samples were not of the expected identity and have not yet been described as new psychoactive substances in the literature, this study presents a full characterisation of each compound. As exemplified by this rapid identification of three unexpected new psychoactive substances, drug checking can be used as an effective method to monitor the unregulated drug market.

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Purpose: Mentored medical student (MS) research opportunities in radiation oncology (RO) provide in-depth exposure to the specialty and may promote greater interest in a career in RO. Many radiation oncologists conduct research; however, the extent to which they directly engage MSs in their research is unknown. The purpose of this study was to characterize MS authorship in American Society for Radiation Oncology (ASTRO) journals. Methods and Materials: The byline and abstract of all scientific articles (ie, clinical, basic science, training/education) and case reports published from 2019 to 2021 in the International Journal of Radiation Oncology, Biology, and Physics; Practical Radiation Oncology; and Advances in Radiation Oncology were reviewed. Characteristics of MSs and senior authors are reported. Results: A total of 105 of 1785 articles (5.8%) included an MS author, among which 72 (68.6%) were clinical, 13 training/education (12.4%), 12 case reports (11.4%), and 8 basic science (7.6%). MS authors were more common for publications in Advances in Radiation Oncology (9.0%) than Practical Radiation Oncology (6.4%) or the International Journal of Radiation Oncology, Biology, and Physics (4.2%; P = .002). There were 125 unique MS authors from 72 institutions, among which 40 were first author (32.0%), 28 second author (22.4%), and 57 third (or higher) author (45.6%). There were 88 unique senior authors from 55 institutions, among which 10 (11.3%) were on 2 or more MS publications, and 57 (64.7%) shared the same institution as the MS. The median number of articles per mentor institution was 1 (interquartile range, 1-2), and the mentor institutions in the upper quartile in terms of number of MS publications accounted for 53 (50.5%) of all MS publications. Conclusions: Few publications in American Society for Radiation Oncology journals include MS authors with mentorship disproportionately from a small number of academic faculty at select institutions. These findings suggest that there is great potential for radiation oncologists to proactively engage more students in their work.

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Aryl-maleimides undergo a novel [2+4]-photodimerization instead of the expected [2+2]-photodimerization under both direct irradiation with visible light and under sensitized energy transfer conditions. This new excited state reactivity in aryl-maleimides is deciphered through photochemical, photophysical, and spectroscopic studies. The stereochemistry of the photodimer depends on the type of non-bonding interactions prevalent during photodimerization which is in turn dictated by the substituents on the maleimide ring. More importantly, the stereochemistry of the photodimer formed is complementary to the product observed under thermal conditions.