Clostridium tanneri sp. nov., isolated from the faecal material of an alpaca.

A strictly anaerobic, Gram-stain-negative rod-shaped bacterium, designated A1-XYC3T, was isolated from the faeces of an alpaca (Lama pacos). On the basis of the results of a comparative 16S rRNA gene sequence analysis, the isolate was assigned to the genus Clostridium with the highest sequence similarities to Clostridium magnum DSM 2767T (96.8 %), Clostridium carboxidivorans P7T (96.3 %) and Clostridium aciditolerans JW/YJL-B3T (96.1 %). The average nucleotide identity between A1-XYC3T, C. magnum, C. carboxidivorans and C. aciditolerans was 77.4, 76.1 and 76.6  %, respectively. The predominant components of the cellular fatty acids of A1-XYC3T were C14 : 0, C16 : 0 and summed feature 10, containing C18:0/C17:0 cyclo. The DNA G+C content was 32.4 mol%. On the basis of biochemical, phylogenetic, genotypic and chemotaxonomic criteria, this isolate represents a novel species within Clostridium sensu stricto for which the name Clostridium tanneri sp. nov. is proposed. The type strain of this species is strain A1-XYC3T (=CCM 9376T=NRRL B-65691T).

The Impact of Steroid Responder Status on Long-Term Outcomes in Critically Ill Patients With Acute Respiratory Distress Syndrome Receiving High-Dose Glucocorticoids.

Background and objective High-dose intravenous pulsed glucocorticosteroids (GCS) are not part of the standard treatment in acute respiratory distress syndrome (ARDS), and the evidence supporting their use is conflicting. In clinical practice, however, they are used in specialist settings when clinico-patho-radiological features suggest a potentially steroid-responsive pattern, or as a last resort in cases where patients are unable to be weaned off mechanical ventilation. This study aimed to investigate if an early objective response to high-dose GCS treatment in selected critically ill patients is predictive of survival in ARDS. Methods This study involved a case series of 63 patients treated at a tertiary specialist respiratory ICU between 2009 and 2017 who received high-dose GCS for ARDS following a multidisciplinary board agreement. Patients were stratified according to the change in their modified lung injury score (mLIS) between days 0 and 10 following GCS initiation. Changes in mLIS (range: 0-4) were grouped as follows - full responders: ≥2, partial responders: ≥1 and <2, and non-responders: <1. Mortality on discharge and at 6, 12, 18, and 24 months post-ICU discharge was assessed for each group. Data were analysed using logistic regression and a receiver operating curve (ROC) to determine a statistically significant association between the change in mLIS and survival. Results Of the 63 patients, there were seven full responders, 12 partial responders, and 44 non-responders to high-dose GCS. Overall mortality at ICU discharge and 6, 12, 18 and 24 months post-discharge was 29/63 (46.0%), 33/63 (52.4%), 34/63 (54.0%), 34/63 (54.0%), and 35/63 (55.6%) respectively. Mortality was significantly lower in the partial and full-response groups than in the non-response group at all time frames. Logistic regression showed a significant association between the change in mLIS and survival (p<0.001), and a ROC demonstrated that categorising the change in mLIS was a good predictive model for survival (c-statistic 0.86). Conclusions Measuring the change in mLIS by day 10 following high-dose GCS administration for ARDS may be clinically useful in prognosticating such patients. Further research using mLIS as a measure of response to GCS, and larger datasets to enable the evaluation of prognostic factors, may assist clinicians in predicting which patients with persistent ARDS are likely to respond to GCS therapy.

Bacteroides vicugnae sp. nov. isolated from the fecal material of an alpaca.

Two strictly anaerobic, Gram-stain-negative rod-shaped bacterial isolates, A2-P53T and A1-P5, were isolated from an enrichment of fecal material from two alpacas (Vicugna pacos). Based on a comparative 16S rRNA gene sequence analysis, the isolates were assigned to the genus Bacteroides with the highest sequence similarities to Bacteroides koreensis YS-aM39T (A2- P53T 97.7% and A1-P5 97.9%). Additionally, the average nucleotide identity and digital DNA-DNA hybridization values between these isolates and their closest relatives within Bacteroides were less than 92.1% and 49.1%, respectively. The average nucleotide identity between isolates A2-P53T and A1-P5 was 99.9%. The predominant cellular fatty acid for isolates A2-P53T and A1-P5 was C15:0 antesio. The G+C % content of the isolates was 41.7%. Based on biochemical, phylogenetic, genotypic, and chemotaxonomic criteria, these isolates A2-P53T and A1-P5 represent two individual strains of a novel species within the genus Bacteroides for which the name Bacteroides vicugnae sp. nov. is proposed. The type strain of this species is strain A2-P53T (CCUG 77273T=CCM 9377T=NRRL B-65693T).

Therapeutic drug monitoring of osimertinib in EGFR mutant non-small cell lung cancer by dried blood spot and plasma collection: A pilot study.

AIMS: Therapeutic drug monitoring (TDM) has led to significant improvements in individualized medical care, although its implementation in oncology has been limited to date. Tyrosine kinase inhibitors (TKIs) are a group of therapies for which TDM has been suggested. Osimertinib is one such therapy used in the treatment of epidermal growth factor receptor (EGFR) mutation-driven lung cancer. Herein, we describe a prospective pilot study involving 21 patients on osimertinib primarily as a preliminary evaluation of drug levels in a real-world setting. METHODS: Concentrations of the drug and its primary metabolites were measured with a validated liquid chromatography-mass spectrometry (LC-MS) assay across serial timepoints. As part of this study, inter-individual variability by dose and ethnicity as well as intra-individual variability across timepoints are explored. Furthermore, we attempted to validate dried blood spot (DBS)-based quantitation as an accurate alternative to plasma quantitation. RESULTS: Successful quantitation of osimertinib and primary metabolites was achieved for our subjects. Compound plasma levels were highly correlated to DBS levels. There was no significant difference in concentrations with ethnicity or dosing or intra-individual variability across timepoints. CONCLUSIONS: As such, we demonstrate that TDM for osimertinib is practical for future trials. We also validated the use of DBS as an alternative to conventional quantitation for exploration of TDM for osimertinib in larger trials and for other targeted therapies.

Scanning the aged to minimize missed injury: An EAST multicenter study.

BACKGROUND: Despite the high incidence of blunt trauma in older adults, there is a lack of evidence-based guidance for computed tomography (CT) imaging in this population. We aimed to identify an algorithm to guide use of a Pan-Scan (Head/C-spine/Torso) or a Selective Scan (Head/C-spine ± Torso). We hypothesized that a patient's initial history and exam could be used to guide imaging. METHODS: We prospectively studied blunt trauma patients aged 65+ at 18 Level I/II trauma centers. Patients presenting >24 h after injury or who died upon arrival were excluded. We collected history and physical elements and final injury diagnoses. Injury diagnoses were categorized into CT body regions of Head/C-spine or Torso (chest, abdomen/pelvis, and T/L spine). Using machine learning and regression modeling as well as a priori clinical algorithms based, we tested various decision rules against our dataset. Our priority was to identify a simple rule which could be applied at the bedside, maximizing sensitivity (Sens) and negative predictive value (NPV) to minimize missed injuries. RESULTS: We enrolled 5,498 patients with 3,082 injuries. Nearly half (47.1%, n = 2,587) had an injury within the defined CT body regions. No rule to guide a Pan-Scan could be identified with suitable Sens/NPV for clinical use. A clinical algorithm to identify patients for Pan-Scan, using a combination of physical exam findings and specific high-risk criteria, was identified and had a Sens of 0.94 and NPV of 0.86 This rule would have identified injuries in all but 90 patients (1.6%) and would theoretically spare 11.9% (655) of blunt trauma patients a torso CT. CONCLUSIONS: Our findings advocate for Head/Cspine CT in all geriatric patients with the addition of torso CT in the setting of positive clinical findings and high-risk criteria. Prospective validation of this rule could lead to streamlined diagnostic care of this growing trauma population. LEVEL OF EVIDENCE: Level 2, Diagnostic Tests or Criteria.

A Retrospective Comparison of Medication Recommendations Between a Cardiologist and ChatGPT-4 for Hypertension Patients in a Rural Clinic.

Background With ChatGPT demonstrating impressive abilities in solving clinical vignettes and medical questions, there is still a lack of studies assessing ChatGPT using real patient data. With real-world cases offering added complexity, ChatGPT's utility in treatment using such data must be tested to better assess its accuracy and dependability. In this study, we compared a rural cardiologist's medication recommendations to that of GPT-4 for patients with lab review appointments. Methodology We reviewed the lab review appointments of 40 hypertension patients, noting their age, sex, medical conditions, medications and dosage, and current and past lab values. The cardiologist's medication recommendations (decreasing dose, increasing dose, stopping, or adding medications) from the most recent lab visit, if any, were recorded for each patient. Data collected from each patient was inputted into GPT-4 using a set prompt and the resulting medication recommendations from the model were recorded. Results Out of the 40 patients, 95% had conflicting overall recommendations between the physician and GPT-4, with only 10.2% of the specific medication recommendations matching between the two. Cohen's kappa coefficient was -0.0127, indicating no agreement between the cardiologist and GPT-4 for providing medication changes overall for a patient. Possible reasons for this discrepancy can be differing optimal lab value ranges, lack of holistic analysis by GPT-4, and a need for providing further supplementary information to the model. Conclusions The study findings showed a significant difference between the cardiologist's medication recommendations and that of ChatGPT-4. Future research should continue to test GPT-4 in clinical settings to validate its abilities in the real world where more intricacies and challenges exist.

Trade-offs, trade-ups, and high mutational parallelism underlie microbial adaptation during extreme cycles of feast and famine.

Microbes are evolutionarily robust organisms capable of rapid adaptation to complex stress, which enables them to colonize harsh environments. In nature, microbes are regularly challenged by starvation, which is a particularly complex stress because resource limitation often co-occurs with changes in pH, osmolarity, and toxin accumulation created by metabolic waste. Often overlooked are the additional complications introduced by eventual resource replenishment, as successful microbes must withstand rapid environmental shifts before swiftly capitalizing on replenished resources to avoid invasion by competing species. To understand how microbes navigate trade-offs between growth and survival, ultimately adapting to thrive in environments with extreme fluctuations, we experimentally evolved 16 Escherichia coli populations for 900 days in repeated feast/famine conditions with cycles of 100-day starvation before resource replenishment. Using longitudinal population-genomic analysis, we found that evolution in response to extreme feast/famine is characterized by narrow adaptive trajectories with high mutational parallelism and notable mutational order. Genetic reconstructions reveal that early mutations result in trade-offs for biofilm and motility but trade-ups for growth and survival, as these mutations conferred positively correlated advantages during both short-term and long-term culture. Our results demonstrate how microbes can navigate the adaptive landscapes of regularly fluctuating conditions and ultimately follow mutational trajectories that confer benefits across diverse environments.

Single-cell multi-omics reveals insights into differentiation of rare cell types in mucinous colorectal cancer.

Neuroendocrine cells have been implicated in therapeutic resistance and worse overall survival in many cancer types. Mucinous colorectal cancer (mCRC) is uniquely enriched for enteroendocrine cells (EECs), the neuroendocrine cell of the normal colon epithelium, as compared to non-mucinous CRC. Therefore, targeting EEC differentiation may have clinical value in mCRC. Here, single cell multi-omics was used to uncover epigenetic alterations that accompany EEC differentiation, identify STAT3 as a novel regulator of EEC specification, and discover a rare cancer-specific cell type with enteric neuron-like characteristics. Further experiments demonstrated that lysine-specific demethylase 1 (LSD1) and CoREST2 mediate STAT3 demethylation and regulate STAT3 chromatin binding. Knockdown of CoREST2 in an orthotopic xenograft mouse model resulted in decreased primary tumor growth and lung metastases. In culmination, these results provide rationale for new LSD1 inhibitors that target the interaction between LSD1 with STAT3 or CoREST2, which may improve clinical outcomes for patients with mCRC.

Top/Middle-Down Characterization of α-Synuclein Glycoforms.

α-Synuclein is an intrinsically disordered protein that plays a critical role in the pathogenesis of neurodegenerative disorders, such as Parkinson's disease. Proteomics studies of human brain samples have associated the modification of the O-linked N-acetyl-glucosamine (O-GlcNAc) to several synucleinopathies; in particular, the position of the O-GlcNAc can regulate protein aggregation and subsequent cell toxicity. There is a need for site specific O-GlcNAc α-synuclein screening tools to direct better therapeutic strategies. In the present work, for the first time, the potential of fast, high-resolution trapped ion mobility spectrometry (TIMS) preseparation in tandem with mass spectrometry assisted by an electromagnetostatic (EMS) cell, capable of electron capture dissociation (ECD), and ultraviolet photodissociation (213 nm UVPD) is illustrated for the characterization of α-synuclein positional glycoforms: T72, T75, T81, and S87 modified with a single O-GlcNAc. Top-down 213 nm UVPD and ECD MS/MS experiments of the intact proteoforms showed specific product ions for each α-synuclein glycoforms associated with the O-GlcNAc position with a sequence coverage of ∼68 and ∼82%, respectively. TIMS-MS profiles of α-synuclein and the four glycoforms exhibited large structural heterogeneity and signature patterns across the 8+-15+ charge state distribution; however, while the α-synuclein positional glycoforms showed signature mobility profiles, they were only partially separated in the mobility domain. Moreover, a middle-down approach based on the Val40-Phe94 (55 residues) chymotrypsin proteolytic product using tandem TIMS-q-ECD-TOF MS/MS permitted the separation of the parent positional isomeric glycoforms. The ECD fragmentation of the ion mobility and m/z separated isomeric Val40-Phe94 proteolytic peptides with single O-GlcNAc in the T72, T75, T81, and S87 positions provided the O-GlcNAc confirmation and positional assignment with a sequence coverage of ∼80%. This method enables the high-throughput screening of positional glycoforms and further enhances the structural mass spectrometry toolbox with fast, high-resolution mobility separations and 213 nm UVPD and ECD fragmentation capabilities.

Disparities in Rates of Multitarget Stool DNA Test Completion for Colorectal Cancer Screening.

GOALS: The aim was to assess patient adherence to multitarget stool DNA testing as well as factors associated with adherence. BACKGROUND: In the United States, disparities in colorectal cancer screening exist along racial and socioeconomic lines. While some studies suggest that stool-based screening tests may help reduce the screening gap, the data for multitarget stool DNA testing is unclear. STUDY: We conducted a single-center retrospective cohort study on multitarget stool DNA testing ordered between April 2020 and July 2021. We calculated the proportion of patients who completed testing and used multivariate logistic regression to identify covariates associated with test adherence. RESULTS: Among 797 patients ordered for multitarget stool DNA testing, 481 patients (60.4%) completed testing. Adherence rates by patient subgroups ranged from 35.8% to 78.1%. Higher test adherence was found in Asian patients (odds ratio 2.65, 95% CI 1.36-5.18) and those who previously completed colorectal cancer screening (OR 1.45, 95% CI 1.01-2.09), while Black patients (OR 0.58, 95% CI 0.39-0.87), patients with resident primary care physicians (OR 0.34, 95% CI 0.21-0.56), and patients contacted through an outreach program (OR 0.47, 95% CI 0.25-0.87) had lower adherence. CONCLUSIONS: A significant proportion of patients ordered for multitarget stool DNA testing did not complete testing. Differences in adherence rates among patient subgroups may be reflective of underlying disparities in health care access.

Using high-frequency monitoring data to quantify city-wide suspended-sediment load and evaluate TMDL goals.

Excess sediment is a common reason water bodies in the USA become listed as impaired resulting in total maximum daily loads (TMDL) that require municipalities to invest millions of dollars annually on management practices aimed at reducing suspended-sediment loads (SSLs), yet monitoring data are rarely used to quantify SSLs and track TMDL progress. A monitoring network was created to quantify the SSL from the City of Roanoke, Virginia, USA (CoR), to the Roanoke River and Tinker Creek and help guide TMDL assessment and implementation. Suspended-sediment concentrations were estimated between 2020 and 2022 from high-frequency turbidity data using surrogate linear-regression models. Sixty-one percent of the total three-year SSL resulted from five large storm events. The average suspended-sediment yield from the CoR (58.1 metric tons/km2/year) was similar to other urban watersheds in the Eastern United States; however, the yield was nearly five times larger than the TMDL allocation (12.2 metric tons/km2/year). The TMDL allocated load was modeled based on a predominantly forested reference watershed and may not be a practical target for highly impervious watersheds within the CoR. The TMDL model used daily input data which likely does not capture the full range of SSLs during storm events, particularly from flashy urban streams. The average SSL following the five large storm events doubled that of the CoR's annual allocated load from the TMDL. The results of this study highlight the importance of using high-frequency monitoring data to accurately estimate SSLs and evaluate TMDLs in urban areas.

Current use of the National Surgical Quality Improvement Program surgical risk calculator in academic surgery: a mixed-methods study.

Background: This study aims to quantitatively assess use of the NSQIP surgical risk calculator (NSRC) in contemporary surgical practice and to identify barriers to use and potential interventions that might increase use. Materials and methods: We performed a cross-sectional study of surgeons at seven institutions. The primary outcomes were self-reported application of the calculator in general clinical practice and specific clinical scenarios as well as reported barriers to use. Results: In our sample of 99 surgeons (49.7% response rate), 73.7% reported use of the NSRC in the past month. Approximately half (51.9%) of respondents reported infrequent NSRC use (<20% of preoperative discussions), while 14.3% used it in ≥40% of preoperative assessments. Reported use was higher in nonelective cases (30.2% vs 11.1%) and in patients who were ≥65 years old (37.1% vs 13.0%), functionally dependent (41.2% vs 6.6%), or with surrogate consent (39.9% vs 20.4%). NSRC use was not associated with training status or years in practice. Respondents identified a lack of influence on the decision to pursue surgery as well as concerns regarding the calculator's accuracy as barriers to use. Surgeons suggested improving integration to workflow and better education as strategies to increase NSRC use. Conclusions: Many surgeons reported use of the NSRC, but few used it frequently. Surgeons reported more frequent use in nonelective cases and frail patients, suggesting the calculator is of greater utility for high-risk patients. Surgeons raised concerns about perceived accuracy and suggested additional education as well as integration of the calculator into the electronic health record.

Metaproteomics reveals functional partitioning and vegetational variation among permafrost-affected Arctic soil bacterial communities.

Microbial activity in Arctic soils controls the cycling of significant stores of organic carbon and nutrients. We studied in situ processes in Alaskan soils using original metaproteomic methods in order to relate important heterotrophic functions to microbial taxa and to understand the microbial response to Arctic greening. Major bacterial groups show strong metabolic specialization in organic topsoils. α-/ß-/γ-Proteobacteria specialized in the acquisition of small, soluble compounds, whereas Acidobacteria, Actinobacteria, and other detritosphere groups specialized in the degradation of plant-derived polymers. α-/ß-/γ-Proteobacteria dominated the expression of transporters for common root exudates and limiting nitrogenous compounds, supporting an ecological model of dependence upon plants for carbon and competition with plants for nitrogen. Detritosphere groups specialized in distinct substrates, with Acidobacteria producing the most enzymes for hemicellulose depolymerization. Acidobacteria was the most active group across the three plant ecotypes sampled-the largely nonvascular, lower biomass intertussock and the largely vascular, higher biomass tussock and shrub. Functional partitioning among bacterial groups was stable between plant ecotypes, but certain functions associated with α-/ß-/γ-Proteobacteria were more strongly expressed in higher biomass ecotypes. We show that refined metaproteomic approaches can elucidate soil microbial ecology as well as biogeochemical trajectories of major carbon stocks. IMPORTANCE The Arctic is warming twice as fast as the rest of the planet, and Arctic soils currently store twice as much carbon as the entire atmosphere-two facts that make understanding how Arctic soil microbial communities are responding to climate change particularly urgent. Greening of vegetation cover across the Arctic landscape is one of the most prominent climate-driven shifts in Arctic terrestrial ecology, with potentially profound effects on biogeochemical cycling by the soil microbiome. Here we use metaproteomics to document microbial metabolic functions that drive soil carbon and nutrient cycling processes in an Arctic tundra landscape. We identify functional roles among bacterial taxonomic groups that are largely stable across vegetation types, with certain functions strongly expressed by rhizosphere groups reflecting a community metabolic response to greening.

PSMA Expression Correlates with Improved Overall Survival and VEGF Expression in Glioblastoma.

BACKGROUND: Glioblastomas are the most common and fatal primary brain malignancy in adults. There is a growing interest in identifying the molecular mechanisms of these tumors to develop novel treatments. Glioblastoma neo-angiogenesis is driven by VEGF, and another potential molecule linked to angiogenesis is PSMA. Our study suggests the potential for an association between PSMA and VEGF expression in glioblastoma neo-vasculature. METHODS: Archived IDH1/2 wild-type glioblastomas were accessed; demographic and clinical outcomes were recorded. PSMA and VEGF expression by IHC were examined. Patients were dichotomized into PSMA expression high (3+) and low (0-2+) groups. The association between PSMA and VEGF expression was evaluated using Chi2 analysis. OS in PSMA high and low expression groups were compared using multi-linear regression. RESULTS: In total, 247 patients with IDH1/2 wild-type glioblastoma with archival tumor samples (between 2009-2014) were examined. PSMA expression correlated positively with VEGF expression (p = 0.01). We detected a significant difference in median OS between PSMA vascular endothelial expression high and low groups-16.1 and 10.8 months, respectively (p = 0.02). CONCLUSION: We found a potential positive correlation between PSMA and VEGF expression. Secondly, we showed a potential positive correlation between PSMA expression and overall survival.

Improving Post-procedure Outcomes With Clinical Care Pathway for Enteral Access.

Our health system introduced an enteral access clinical pathway (EACP) hoping to increase nutritionist consults and decrease presentation to the Emergency Department, readmission to the hospital, and overall hospital length of stay. We followed patients with short-term access (STA), longterm access (LTA), and short-long-term conversions (SLT) seen in the six months prior to the EACP launch (baseline group) and the six months after (performance group). The baseline cohort consisted of 2,553 patients and the performance cohort of 2,419 patients. Those in the performance group were more likely to receive a nutrition consult (52.4% vs 48.0%, P < .01), less likely to re-present to the ED (31.9% vs 42.6%, P < .001), and less likely to be readmitted to the hospital (31.0% vs 41.6%, P < .001. These findings suggest that the EACP may increase the likelihood of both expert-driven nutritional support and effective discharge planning for hospitalized patients.

An Evaluation of Sex-Based Differences in Surrogate Consent for Older Adults Undergoing Surgical Intervention.

INTRODUCTION: Differences between female and male patients have been identified in many facets of medicine. We sought to understand whether differences in frequency of surrogate consent for operation exist between older female and male patients. MATERIALS AND METHODS: A descriptive study was designed using data from the hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program. Patients age 65 y and older who underwent operation between 2014 and 2018 were included. RESULTS: Of 51,618 patients identified, 3405 (6.6%) had surrogate consent for surgery. Overall, 7.7% of females had surrogate consent compared to 5.3% of males (P < 0.001). Stratified analysis based on age categories showed no difference in surrogate consent between female and male patients aged 65-74 yy (2.3% versus 2.6%, P = 0.16), but higher rates of surrogate consent in females than males among patients aged 75-84 y old (7.3% versus 5.6%, P < 0.001) and age ≥85 y (29.7% versus 20.8%, P < 0.001). A similar relationship was seen between sex and preoperative cognitive status. There was no difference in preoperative cognitive impairment in female and male patients age 65-74 y (4.4% versus 4.6%, P = 0.58), but higher rates of preoperative cognitive impairment were seen in females than males for those age 75-84 (9.5% versus 7.4%, P < 0.001) and aged ≥85 y (29.4% versus 21.3%, P < 0.001). Matching for age and cognitive impairment, there was no significant difference between rate of surrogate consent in males and females. CONCLUSIONS: Female patients are more likely than males to undergo surgery with surrogate consent. This difference is not based on patient sex alone - females undergoing operation are older than their male counterparts and more likely to be cognitively impaired.

Structure-informed microbial population genetics elucidate selective pressures that shape protein evolution.

Comprehensive sampling of natural genetic diversity with metagenomics enables highly resolved insights into the interplay between ecology and evolution. However, resolving adaptive, neutral, or purifying processes of evolution from intrapopulation genomic variation remains a challenge, partly due to the sole reliance on gene sequences to interpret variants. Here, we describe an approach to analyze genetic variation in the context of predicted protein structures and apply it to a marine microbial population within the SAR11 subclade 1a.3.V, which dominates low-latitude surface oceans. Our analyses reveal a tight association between genetic variation and protein structure. In a central gene in nitrogen metabolism, we observe decreased occurrence of nonsynonymous variants from ligand-binding sites as a function of nitrate concentrations, revealing genetic targets of distinct evolutionary pressures maintained by nutrient availability. Our work yields insights into the governing principles of evolution and enables structure-aware investigations of microbial population genetics.

Palliative Care in a Pandemic: A Multicenter Cohort of Critically Ill Patients with Coronavirus Disease 2019.

Background: Trends in mortality, palliative care, and end-of-life care among critically ill patients with coronavirus disease 2019 (COVID-19) remain underreported. We hypothesized that use of palliative care and end-of-life care would increase over time, because improved understanding of the disease course and prognosis would potentially lead to more frequent use of these services. Patients and Methods: Adult patients with severe acute respiratory syndrome coronavirus 2 infection (SARS-CoV-2) during pandemic wave one (W1: March 2020 to September 2020) or wave two (W2: October 2020 to June 2021) admitted to an intensive care unit (ICU) in one of six northeastern U.S. hospitals were identified and clinical characteristics obtained. Vaccination data were unavailable. Outcomes of interest included mortality, palliative care consultation, and any end-of-life care (including hospice and comfort care). Results: There were 1,904 critically ill patients with COVID-19: 817 (42.9%) in W1 and 1,087 (57.1%) in W2. Patients received mechanical ventilation more often during W1 than W2 (52.9% vs. 46.3%; p = 0.004), with no difference in ICU or hospital length of stay between waves. Mortality between W1 and W2 was similar (31.2% vs. 30.9%; p = 0.888). There was no difference in use of palliative care or any end-of-life care between waves. Patients who died during W2 versus W1 were more likely to have received both mechanical ventilation (77.1% vs. 67.1%; p = 0.007) and palliative care services (52.1% vs. 41.2%; p = 0.009). However, logistic regression adjusted for demographics, baseline comorbid disease, and clinical characteristics showed no difference in mortality (odds ratio [OR], 1.15; 95% confidence interval [CI], 0.89-1.48), palliative care (OR, 1.08; 95% CI, 0.84-1.40), or any end-of-life care (OR, 1.05; 95% CI, 0.82-1.34) in W2 versus W1. Conclusions: Mortality among critically ill patients with COVID-19 has remained constant across two pandemic waves with no change in use of palliative or end-of-life care.

Hypercalcaemia secondary to hypophysitis and cortisol deficiency: another immunotherapy-related adverse event.

Summary: Hypercalcaemia is a common complication seen in malignancy, frequently due to paraneoplastic parathyroid hormone-related peptide production or osteolytic bony metastases. We present a 58-year-old female with immunotherapy-mediated hypophysitis causing secondary cortisol deficiency resulting in severe glucocorticoid-responsive hypercalcaemia. Whilst hypophysitis is a well recognised adverse event in those receiving immunotherapy for advanced malignancy, it does not typically present with hypercalcaemia. The mechanism responsible for hypercalcaemia due to hypocortisolaemia has not been fully elucidated although hypotheses include the effects of volume depletion and thyroxine's action on bone. Prompt treatment with glucocorticoids caused an improvement in the patient's symptoms and corrected her hypercalcaemia which later returned after an attempted glucocorticoid wean. With the increasing uptake of immunotherapy, clinicians should be aware of this unusual presentation of immunotherapy-related hypophysitis and secondary hypocortisolaemia which can be life-threatening if the diagnosis is delayed. Learning points: Immunotherapy can cause inflammation of the pituitary gland resulting in secondary hypocortisolaemia, which can, though rarely, present as hypercalcaemia. Secondary hypocortisolaemia requires prompt recognition and treatment with glucocorticoids. Glucocorticoid replacement leads to rapid clinical and biochemical improvement in these patients. The differential diagnosis for glucocorticoid-responsive hypercalcaemia extends beyond granulomatous disorders (e.g. sarcoidosis, tuberculosis) to adrenocorticotrophic hormone and cortisol deficiency, particularly in patients receiving immunotherapy. Hypocortisolaemia can lead to hypercalcaemia through various proposed mechanisms. Low serum glucocorticoids are associated with reduced blood volume, thus reducing renal calcium excretion. In addition, without glucocorticoid's inhibitory action, thyroxine appears to drive calcium mobilisation from bone.