Sulfide Toxicity as Key Control on Anaerobic Oxidation of Methane in Eutrophic Coastal Sediments.

Coastal zones account for 75% of marine methane emissions, despite covering only 15% of the ocean surface area. In these ecosystems, the tight balance between methane production and oxidation in sediments prevents most methane from escaping into seawater. However, anthropogenic activities could disrupt this balance, leading to an increased methane escape from coastal sediments. To quantify and unravel potential mechanisms underlying this disruption, we used a suite of biogeochemical and microbiological analyses to investigate the impact of anthropogenically induced redox shifts on methane cycling in sediments from three sites with contrasting bottom water redox conditions (oxic-hypoxic-euxinic) in the eutrophic Stockholm Archipelago. Our results indicate that the methane production potential increased under hypoxia and euxinia, while anaerobic oxidation of methane was disrupted under euxinia. Experimental, genomic, and biogeochemical data suggest that the virtual disappearance of methane-oxidizing archaea at the euxinic site occurred due to sulfide toxicity. This could explain a near 7-fold increase in the extent of escape of benthic methane at the euxinic site relative to the hypoxic one. In conclusion, these insights reveal how the development of euxinia could disrupt the coastal methane biofilter, potentially leading to increased methane emissions from coastal zones.

Equine Endothelial Cells Show Pro-Angiogenic Behaviours in Response to Fibroblast Growth Factor 2 but Not Vascular Endothelial Growth Factor A.

Understanding the factors which control endothelial cell (EC) function and angiogenesis is crucial for developing the horse as a disease model, but equine ECs remain poorly studied. In this study, we have optimised methods for the isolation and culture of equine aortic endothelial cells (EAoECs) and characterised their angiogenic functions in vitro. Mechanical dissociation, followed by magnetic purification using an anti-VE-cadherin antibody, resulted in EC-enriched cultures suitable for further study. Fibroblast growth factor 2 (FGF2) increased the EAoEC proliferation rate and stimulated scratch wound closure and tube formation by EAoECs on the extracellular matrix. Pharmacological inhibitors of FGF receptor 1 (FGFR1) (SU5402) or mitogen-activated protein kinase (MEK) (PD184352) blocked FGF2-induced extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and functional responses, suggesting that these are dependent on FGFR1/MEK-ERK signalling. In marked contrast, vascular endothelial growth factor-A (VEGF-A) had no effect on EAoEC proliferation, migration, or tubulogenesis and did not promote ERK1/2 phosphorylation, indicating a lack of sensitivity to this classical pro-angiogenic growth factor. Gene expression analysis showed that unlike human ECs, FGFR1 is expressed by EAoECs at a much higher level than both VEGF receptor (VEGFR)1 and VEGFR2. These results suggest a predominant role for FGF2 versus VEGF-A in controlling the angiogenic functions of equine ECs. Collectively, our novel data provide a sound basis for studying angiogenic processes in horses and lay the foundations for comparative studies of EC biology in horses versus humans.

Sirtuin E deacetylase is required for full virulence of Aspergillus fumigatus.

Aspergillus fumigatus represents a public health problem due to the high mortality rate in immunosuppressed patients and the emergence of antifungal-resistant isolates. Protein acetylation is a crucial post-translational modification that controls gene expression and biological processes. The strategic manipulation of enzymes involved in protein acetylation has emerged as a promising therapeutic approach for addressing fungal infections. Sirtuins, NAD+-dependent lysine deacetylases, regulate protein acetylation and gene expression in eukaryotes. However, their role in the human pathogenic fungus A. fumigatus remains unclear. This study constructs six single knockout strains of A. fumigatus and a strain lacking all predicted sirtuins (SIRTKO). The mutant strains are viable under laboratory conditions, indicating that sirtuins are not essential genes. Phenotypic assays suggest sirtuins' involvement in cell wall integrity, secondary metabolite production, thermotolerance, and virulence. Deletion of sirE attenuates virulence in murine and Galleria mellonella infection models. The absence of SirE alters the acetylation status of proteins, including histones and non-histones, and triggers significant changes in the expression of genes associated with secondary metabolism, cell wall biosynthesis, and virulence factors. These findings encourage testing sirtuin inhibitors as potential therapeutic strategies to combat A. fumigatus infections or in combination therapy with available antifungals.

Eutrophication and Deoxygenation Drive High Methane Emissions from a Brackish Coastal System.

Coastal environments are a major source of marine methane in the atmosphere. Eutrophication and deoxygenation have the potential to amplify the coastal methane emissions. Here, we investigate methane dynamics in the eutrophic Stockholm Archipelago. We cover a range of sites with contrasting water column redox conditions and rates of organic matter degradation, with the latter reflected by the depth of the sulfate-methane transition zone (SMTZ) in the sediment. We find the highest benthic release of methane (2.2-8.6 mmol m-2 d-1) at sites where the SMTZ is located close to the sediment-water interface (2-10 cm). A large proportion of methane is removed in the water column via aerobic or anaerobic microbial pathways. At many locations, water column methane is highly depleted in 13C, pointing toward substantial bubble dissolution. Calculated and measured rates of methane release to the atmosphere range from 0.03 to 0.4 mmol m-2 d-1 and from 0.1 to 1.7 mmol m-2 d-1, respectively, with the highest fluxes at locations with a shallow SMTZ and anoxic and sulfidic bottom waters. Taken together, our results show that sites suffering most from both eutrophication and deoxygenation are hotspots of coastal marine methane emissions.

Endothelial dysfunction in neurodegenerative disease: Is endothelial inflammation an overlooked druggable target?

Neurological diseases with a neurodegenerative component have been associated with alterations in the cerebrovasculature. At the anatomical level, these are centred around changes in cerebral blood flow and vessel organisation. At the molecular level, there is extensive expression of cellular adhesion molecules and increased release of pro-inflammatory mediators. Together, these has been found to negatively impact blood-brain barrier integrity. Systemic inflammation has been found to accelerate and exacerbate endothelial dysfunction, neuroinflammation and degeneration. Here, we review the role of cerebrovasculature dysfunction in neurodegenerative disease and discuss the potential contribution of intermittent pro-inflammatory systemic disease in causing endothelial pathology, highlighting a possible mechanism that may allow broad-spectrum therapeutic targeting in the future.

Solid phase speciation controls copper mobilisation from marine sediments by methanobactin.

Although marine environments represent huge reservoirs of the potent greenhouse gas methane, they currently contribute little to global net methane emissions. Most of the methane is oxidized by methanotrophs, minimizing escape to the atmosphere. Aerobic methanotrophs oxidize methane mostly via the copper (Cu)-bearing enzyme particulate methane monooxygenase (pMMO). Therefore, aerobic methane oxidation depends on sufficient Cu acquisition by methanotrophs. Because they require both oxygen and methane, aerobic methanotrophs reside at oxic-anoxic interfaces, often close to sulphidic zones where Cu bioavailability can be limited by poorly soluble Cu sulphide mineral phases. Under Cu-limiting conditions, certain aerobic methanotrophs exude Cu-binding ligands termed chalkophores, such as methanobactin (mb) exuded by Methylosinus trichosporium OB3b. Our main objective was to establish whether chalkophores can mobilise Cu from Cu sulphide-bearing marine sediments to enhance Cu bioavailability. Through a series of kinetic batch experiments, we investigated Cu mobilisation by mb from a set of well-characterized sulphidic marine sediments differing in sediment properties, including Cu content and phase distribution. Characterization of solid-phase Cu speciation included X-ray absorption spectroscopy and a targeted sequential extraction. Furthermore, in batch experiments, we investigated to what extent adsorption of metal-free mb and Cu-mb complexes to marine sediments constrains Cu mobilisation. Our results are the first to show that both solid phase Cu speciation and chalkophore adsorption can constrain methanotrophic Cu acquisition from marine sediments. Only for certain sediments did mb addition enhance dissolved Cu concentrations. Cu mobilisation by mb was not correlated to the total Cu content of the sediment, but was controlled by solid-phase Cu speciation. Cu was only mobilised from sediments containing a mono-Cu-sulphide (CuSx) phase. We also show that mb adsorption to sediments limits Cu acquisition by mb to less compact (surface) sediments. Therefore, in sulphidic sediments, mb-mediated Cu acquisition is presumably constrained to surface-sediment interfaces containing mono-Cu-sulphide phases.

Factors Associated With Early Palliative Care Among Patients With Heart Failure.

Background: Heart failure (HF) is a progressive, life-limiting illness for which palliative care (PC) is considered standard of care. Among patients that do receive PC, consultation tends to occur late in the illness course. Objective: Our primary aim was to examine patient factors associated with receiving PC in HF. Secondarily, we sought to determine factors associated with early PC encounters. Design: This was a retrospective cohort study of U.S. Veterans with prior hospitalization who died between January 1, 2011 and December 31, 2020. Setting/Subjects: Subjects were Veterans with HF who died with a prior admission to a Veterans Affairs hospital in the United States. Measurements: We calculated the time from PC encounter to death. We characterized HF patients who died without PC, with late PC (≤90 days before death), and with early PC (>90 days before death). Results: We identified 232,079 Veterans with a mean age of (76.5 ± 10.7) years. Within the cohort, 56.5% (n = 131,122) of Veterans died with no PC, 22.5% (n = 52,114) had PC <90 days before death, and 21.0% (n = 48,843) had PC >90 days before death. Veterans who died without PC tended to be younger with fewer comorbidities. Conclusions: While more than 20% of HF patients in our cohort had PC well in advance of death, more than half died without PC. PC involvement seemed to be driven by comorbidities rather than HF. Effective collaboration with Cardiology is needed to identify patients who would benefit from earlier PC involvement.

Preadolescent Suicidal Thoughts and Behaviors: An Intensive Longitudinal Study of Risk Factors.

OBJECTIVE: Dramatic increases in rates of suicidal thoughts and behaviors (STBs) among youth highlight the need to pinpoint early risk factors. This study used intensive longitudinal sampling to assess what the concurrent associations were between risk factors and STB status, how proximal changes in risk factors were related to STB status, and how risk factors prospectively predicted changes in STB status in a preadolescent sample enriched for early childhood psychopathology. METHOD: A total of 192 participants were included from the Parent-Child Interaction Therapy-Emotional Development (PCIT-ED) Study, a longitudinal study of children with and without preschool depression. Participants 7 to 12 years of age completed a diagnostic interview, followed by 12 months of intensive longitudinal sampling, assessing experiences of suicidal ideation and 11 psychosocial variables with known links to STBs in adolescents and adults. Preadolescents with STB history (high-risk) received surveys weekly, and those without STB history (lower-risk) received surveys monthly. RESULTS: Female sex, elevated depressive symptoms, greater use of expressive suppression and rumination, emotional clarity, and perceived burdensomeness were uniquely concurrently associated with the likelihood of STB endorsement. Within the high-risk group, (1) increases in depression, expressive suppression, rumination, and perceived burdensomeness, and decreases in positive affect from weekt to weekt+1 were associated with a higher likelihood of a positive STB status at weekt+1; and (2) higher expressive suppression, perceived burdensomeness, and caregiver criticism and conflict at weekt compared to participants' mean levels prospectively predicted increases in the likelihood of a positive STB report from weekt to weekt+1. CONCLUSION: Psychosocial factors influencing STBs in adolescents and adults also affect preadolescents in day-to-day life. Expressive suppression and perceived burdensomeness consistently emerged as novel risk indicators and potential targets for treatment. In addition, increases in depression, rumination, and caregiver criticism and conflict, as well as decreases in positive affect, might prompt heightened STB screening and assessments for preadolescents with a history of STBs.

Are Quality Scores in the Centers for Medicaid and Medicare Services Merit-based Incentive Payment System Associated With Outcomes After Outpatient Orthopaedic Surgery?

BACKGROUND: The Medicare Merit-based Incentive Payment System (MIPS) ties reimbursement incentives to clinician performance to improve healthcare quality. It is unclear whether the MIPS quality score can accurately distinguish between high-performing and low-performing clinicians. QUESTIONS/PURPOSES: (1) What were the rates of unplanned hospital visits (emergency department visits, observation stays, or unplanned admissions) within 7, 30, and 90 days of outpatient orthopaedic surgery among Medicare beneficiaries? (2) Was there any association of MIPS quality scores with the risk of an unplanned hospital visit (emergency department visits, observation stays, or unplanned admissions)? METHODS: Between January 2018 and December 2019, a total of 605,946 outpatient orthopaedic surgeries were performed in New York State according to the New York Statewide Planning and Research Cooperative System database. Of those, 56,772 patients were identified as Medicare beneficiaries and were therefore potentially eligible. A further 34% (19,037) were excluded because of missing surgeon identifier, age younger than 65 years, residency outside New York State, emergency department visit on the same day as outpatient surgery, observation stay on the same claim as outpatient surgery, and concomitant high-risk or eye procedures, leaving 37,735 patients for analysis. The database does not include a list of all state residents and thus does not allow for censoring of patients who move out of state. We chose this dataset because it includes nearly all hospitals and ambulatory surgery centers in a large geographic area (New York State) and hence is not limited by sampling bias. We included 37,735 outpatient orthopaedic surgical encounters among Medicare beneficiaries in New York State from 2018 to 2019. For the 37,735 outpatient orthopaedic surgical procedures included in our study, the mean ± standard deviation age of patients was 73 ± 7 years, 84% (31,550) were White, and 59% (22,071) were women. Our key independent variable was the MIPS quality score percentile (0 to 19th, 20th to 39th, 40th to 59th, or 60th to 100th) for orthopaedic surgeons. Clinicians in the MIPS program may receive a bonus or penalty based on the overall MIPS score, which ranges from 0 to 100 and is a weighted score based on four subscores: quality, promoting interoperability, improvement activities, and cost. The MIPS quality score, which attempts to reward clinicians providing superior quality of care, accounted for 50% and 45% of the overall MIPS score in 2018 and 2019, respectively. Our main outcome measures were 7-day, 30-day, and 90-day unplanned hospital visits after outpatient orthopaedic surgery. To determine the association between MIPS quality scores and unplanned hospital visits, we estimated multivariable hierarchical logistic regression models controlling for MIPS quality scores; patient-level (age, race and ethnicity, gender, and comorbidities), facility-level (such as bed size and teaching status), surgery and surgeon-level (such as surgical procedure and surgeon volume) covariates; and facility-level random effects. We then used these models to estimate the adjusted rates of unplanned hospital visits across MIPS quality score percentiles after adjusting for covariates in the multivariable models. RESULTS: In total, 2% (606 of 37,735), 2% (783 of 37,735), and 3% (1013 of 37,735) of encounters had an unplanned hospital visit within 7, 30, or 90 days of outpatient orthopaedic surgery, respectively. Most hospital visits within 7 days (95% [576 of 606]), 30 days (94% [733 of 783]), or 90 days (91% [924 of 1013]) were because of emergency department visits. We found very small differences in unplanned hospital visits by MIPS quality scores, with the 20th to 39th percentile of MIPS quality scores having 0.71% points (95% CI -1.19% to -0.22%; p = 0.004), 0.68% points (95% CI -1.26% to -0.11%; p = 0.02), and 0.75% points (95% CI -1.42% to -0.08%; p = 0.03) lower than the 0 to 19th percentile at 7, 30, and 90 days, respectively. There was no difference in adjusted rates of unplanned hospital visits between patients undergoing surgery with a surgeon in the 0 to 19th, 40th to 59th, or 60th to 100th percentiles at 7, 30, or 90 days. CONCLUSION: We found that the rates of unplanned hospital visits after outpatient orthopaedic surgery among Medicare beneficiaries were low and primarily driven by emergency department visits. We additionally found only a small association between MIPS quality scores for individual physicians and the risk of an unplanned hospital visit after outpatient orthopaedic surgery. These findings suggest that policies aimed at reducing postoperative emergency department visits may be the best target to reduce overall postoperative unplanned hospital visits and that the MIPS program should be eliminated or modified to more strongly link reimbursement to risk-adjusted patient outcomes, thereby better aligning incentives among patients, surgeons, and the Centers for Medicare ad Medicaid Services. Future work could seek to evaluate the association between MIPS scores and other surgical outcomes and evaluate whether annual changes in MIPS score weighting are independently associated with clinician performance in the MIPS and regarding clinical outcomes. LEVEL OF EVIDENCE: Level III, therapeutic study.

Evaluation and post-transplant management of children after multi-organ-with-kidney transplantation.

Multi-organ transplantation involves the transplant of two or more organs from a single donor into a single recipient; in most cases, one of these organs is a kidney. Multi-organ transplantation is uncommon in pediatric transplantation but can be life-saving or significantly life-improving for children with rare diseases, including primary heart, liver, pancreas, or intestinal failure with secondary kidney failure, metabolic disorders, and genetic conditions causing multi-organ dysfunction. This manuscript reviews the current state of pediatric multi-organ transplantation that includes a kidney, with a focus on indications, evaluation, and key differences in management compared to kidney-alone transplantation. Guidelines and consensus statements for pediatric multi-organ transplantation are nonexistent; this review condenses reported statistics and peer-reviewed expert opinion while highlighting areas in need of further research.

Mapping the Discharge Process After Surgery.

Importance: Care transition models are structured approaches used to ensure the smooth transfer of patients between health care settings or levels of care, but none currently are tailored to the surgical patient. Tailoring care transition models to the unique needs of surgical patients may lead to significant improvements in surgical outcomes and reduced care fragmentation. The first step to developing surgical care transition models is to understand the surgical discharge process. Objective: To map the surgical discharge process in a sample of US hospitals and identify key components and potential challenges specific to a patient's discharge after surgery. Design, Setting, and Participants: This qualitative study followed a cognitive task analysis framework conducted between January 1, 2022, and April 1, 2023, in Veterans Health Administration (VHA) hospitals. Observations (n = 16) of discharge from inpatient care after a surgical procedure were conducted in 2 separate VHA surgical units. Interviews (n = 13) were conducted among VHA health care professionals nationwide. Exposure: Postoperative hospital discharge. Main Outcomes and Measures: Data were coded according to the principles of thematic analysis, and a swim lane process map was developed to represent the study findings. Results: At the hospitals in this study, the discharge process observed for a surgical patient involved multidisciplinary coordination across the surgery team, nursing team, case managers, dieticians, social services, occupational and physical therapy, and pharmacy. Important components for a surgical discharge that were not incorporated in the current care transition models included wound care education and supplies; pain control; approvals for nonhome postdischarge locations; and follow-up plans for wounds, ostomies, tubes, and drains at discharge. Potential challenges to the surgical discharge process included social situations (eg, home environment and caregiver availability), team communication issues, and postdischarge care coordination. Conclusions and Relevance: These findings suggest that current and ongoing studies of discharge care transitions for a patient after surgery should consider pain control; wounds, ostomies, tubes, and drains; and the impact of challenging social situations and interdisciplinary team coordination on discharge success.

Day-to-day bidirectional associations between sleep and emotion states in early childhood: Importance of end-of-day mood for sleep quality.

OBJECTIVES: Poor quality sleep can impact emotions and emotion regulation, resulting in a "sleep-mood" cycle where poor sleep affects mood and vice-versa. This relationship is poorly understood during early childhood, when sleep patterns and emotion displays are rapidly changing. This study aimed to understand the day-to-day effects of poor sleep on emotions in preschoolers by using objective (actigraphy) and subjective (ecological momentary assessment) measures to assess both between- and within-child effects. We hypothesized that disrupted sleep would lead to affect disruptions and vice versa. METHODS: This study included 133 preschoolers and their caregivers recruited from the community. Children's sleep was measured via actigraphy (ActiGraph GT3X+) across 1week. Affect was collected concurrently via caregiver report during an ecological momentary assessment protocol. Caregivers reported on their child's affect four times per day: morning, afternoon, early evening, and before bed. RESULTS: Multilevel modeling analyses revealed that children with sleep disturbances displayed less positive affect overall, more negative affect in the evenings, and alterations in positive affect lability, and that daytime affect was associated with subsequent nighttime sleep. Within-child associations also showed fluctuations in positive affect correlated with shorter sleep durations and later bedtimes. CONCLUSIONS: This study identified both between- and within-child associations between sleep and affect in early childhood, revealing a dynamic and reciprocal relationship between the two. These findings highlight the importance of considering both sleep and affect in early childhood interventions, as promoting positive affect may enhance sleep quality and vice versa.

Short-Term (6 Months or Less) Pain in Cemented versus Cementless Total Knee Arthroplasty: A Systematic Review and Meta-Analysis.

BACKGROUND: Cementless total knee arthroplasty (TKA) has increased in popularity to potentially improve survivorship. Radiostereometric studies demonstrate increased component migration during the first 3 to 6 months in cementless constructs, generating concern for increased postoperative pain during early osseointegration. The purpose of this study was to evaluate short-term (≤ 6 months) pain and function in cemented versus cementless TKA. We hypothesized that cementless TKA patients report increased pain during the short-term (≤ 6 months) postoperative period. METHODS: The MEDLINE, EMBASE, CINAHL, and Cochrane Libraries were searched for studies evaluating short-term (≤ 6 months) outcomes of cemented versus cementless primary TKA. Studies involving hybrid fixation were excluded. A meta-analysis was performed using standardized mean difference for primary outcomes (early postoperative pain) and weighted mean difference (WMD) for secondary outcomes (early postoperative function). RESULTS: There were eleven studies included. There was no significant difference in acute postoperative pain between cemented and cementless TKA within 6 months of index TKA (standardized mean difference 0.08 in favor of cemented TKA; P = .10). Early postoperative forgotten joint scores (WMD 0.81; P = .81) and knee injury and osteoarthritis outcome scores for joint replacement (WMD 0.80 in favor of cemented TKA; P = .14) were also similar between groups. CONCLUSIONS: There is no difference in short-term (≤ 6 months) pain or early function between patients receiving cemented and cementless TKA. This suggests that surgeons may utilize cementless TKA without fear of increased pain due to micromotion within 6 months of index arthroplasty. However, additional studies with uniform assessment methods are needed to further inform differences in short-term pain and early functional outcomes between cemented and cementless TKA.

Comparing the effects of decreasing prescription opioid shipments and the release of an abuse deterrent OxyContin formulation on opioid overdose fatalities in WV: an interrupted time series study.

INTRODUCTION: The 2010 release of an abuse deterrent formulation (ADF) of OxyContin, a brand name prescription opioid, has been cited as a major driver for the reduction in prescription drug misuse and the associated increasing illicit opioid use and overdose rates. However, studies of this topic often do not account for changes in supplies of other prescription opioids that were widely prescribed before and after the ADF OxyContin release, including generic oxycodone formulations and hydrocodone. We therefore sought to compare the impact of the ADF OxyContin release to that of decreasing prescription opioid supplies in West Virginia (WV). METHODS: Opioid tablet shipment and overdose data were extracted from The Washington Post ARCOS (2006-2014) and the WV Forensic Drug Database (2005-2020), respectively. Locally estimated scatterplot smoothing (LOESS) was used to estimate the point when shipments of prescription opioids to WV began decreasing, measured via dosage units and morphine milligram equivalents (MMEs). Interrupted time series analysis (ITSA) was used to compare the impact LOESS-identified prescription supply changes and the ADF OxyContin release had on prescription (oxycodone and hydrocodone) and illicit (heroin, fentanyl, and fentanyl analogues) opioid overdose deaths in WV. Model fit was compared using Akaike Information Criteria (AIC). RESULTS: The majority of opioid tablets shipped to WV from 2006 to 2014 were generic oxycodone or hydrocodone, not OxyContin. After accounting for a 6-month lag from ITSA models using the LOESS-identified change in prescription opioid shipments measured via dosage units (2011 Q3) resulted in the lowest AIC for both prescription (AIC = -188.6) and illicit opioid-involved overdoses (AIC = -189.4), indicating this intervention start date resulted in the preferred model. The second lowest AIC was for models using the ADF OxyContin release as an intervention start date. DISCUSSION: We found that illicit opioid overdoses in WV began increasing closer to when prescription opioid shipments to the state began decreasing, not when the ADF OxyContin release occurred. Similarly, the majority of opioid tablets shipped to the state for 2006-2014 were generic oxycodone or hydrocodone. This may indicate that diminishing prescription supplies had a larger impact on opioid overdose patterns than the ADF OxyContin release in WV.

Ribonucleotides differentially modulate oral glutamate detection thresholds.

The savory or umami taste of the amino acid glutamate is synergistically enhanced by the addition of the purines inosine 5'-monophosphate (IMP) and guanosine 5'-monophosphate (GMP) disodium salt. We hypothesized that the addition of purinergic ribonucleotides, along with the pyrimidine ribonucleotides, would decrease the absolute detection threshold of (increase sensitivity to) l-glutamic acid potassium salt (MPG). To test this, we measured both the absolute detection threshold of MPG alone and with a background level (3 mM) of 5 different 5'-ribonucleotides. The addition of the 3 purines IMP, GMP, and adenosine 5'-monophosphate (AMP) lowered the MPG threshold in all participants (P < 0.001), indicating they are positive modulators or enhancers of glutamate taste. The average detection threshold of MPG was 2.08 mM, and with the addition of IMP, the threshold was decreased by approximately 1.5 orders of magnitude to 0.046 mM. In contrast to the purines, the pyrimidines uridine 5'-monophosphate (UMP) and cytidine 5'-monophosphate (CMP) yielded different results. CMP reliably raised glutamate thresholds in 10 of 17 subjects, suggesting it is a negative modulator or diminisher of glutamate taste for them. The rank order of effects on increasing sensitivity to glutamate was IMP > GMP> AMP >> UMP// CMP. These data confirm that ribonucleotides are modulators of glutamate taste, with purines enhancing sensitivity and pyrimidines displaying variable and even negative modulatory effects. Our ability to detect the co-occurrence of glutamate and purines is meaningful as both are relatively high in evolutionarily important sources of nutrition, such as insects and fermented foods.

Seasonal dynamics of the microbial methane filter in the water column of a eutrophic coastal basin.

In coastal waters, methane-oxidizing bacteria (MOB) can form a methane biofilter and mitigate methane emissions. The metabolism of these MOBs is versatile, and the resilience to changing oxygen concentrations is potentially high. It is still unclear how seasonal changes in oxygen availability and water column chemistry affect the functioning of the methane biofilter and MOB community composition. Here, we determined water column methane and oxygen depth profiles, the methanotrophic community structure, methane oxidation potential, and water-air methane fluxes of a eutrophic marine basin during summer stratification and in the mixed water in spring and autumn. In spring, the MOB diversity and relative abundance were low. Yet, MOB formed a methane biofilter with up to 9% relative abundance and vertical niche partitioning during summer stratification. The vertical distribution and potential methane oxidation of MOB did not follow the upward shift of the oxycline during summer, and water-air fluxes remained below 0.6 mmol m-2 d-1. Together, this suggests active methane removal by MOB in the anoxic water. Surprisingly, with a weaker stratification, and therefore potentially increased oxygen supply, methane oxidation rates decreased, and water-air methane fluxes increased. Thus, despite the potential resilience of the MOB community, seasonal water column dynamics significantly influence methane removal.

Measured versus estimated energy requirement in hospitalized patients.

BACKGROUND & AIM: Failure to identify a patient's energy requirement has a variety of consequences both physiological and economical. Previous studies have shown that predictive formulas, including the Harris Benedict equation (HB), both over- and underestimates energy requirement in severely ill patients and healthy younger adults, compared to the golden standard, indirect calorimetry (IC). The comparison between measured and estimated energy requirements in hospitalized patients in regular wards is underreported. The aim of this study was to assess the agreement between measured energy requirements and requirements estimated by HB in the individual hospitalized patients, and to investigate whether those findings were associated with other specific patient characteristics. METHODS: IC (n = 86) was used to measure resting energy expenditure (REE) and bioimpedance analysis (BIA) (n = 67) was used for body composition in patients admitted to Aalborg University Hospital. Furthermore, height, weight, body mass index, calf circumference, while information regarding hospital ward, vital values, dieticians estimated energy requirements and blood samples were collected in the patients' electronic medical records. Bland-Altman plots, multiple linear regression analysis, and Chi2 tests were performed. RESULTS: On average a difference between IC compared with the HB (6.2%), dietitians' estimation (7.8%) and BIA (4.50%) was observed (p < 0.05). Association between REE and skeletal muscle mass (SMM) (R2 = 0.58, ß = 149.0 kJ), body fat mass (BFM) (R2 = 0.51, ß = 59.1 kJ), and weight (R2 = 0.62, ß = 45.6 kJ) were found (p < 0.05). A positive association between measured REE and HB were found in the following variables (p < 0.05): CRP, age, surgical patients, and respiratory rate. CONCLUSION: This study found a general underestimation of estimated energy expenditure compared to measured REE. A positive correlation between measured REE and SMM, BRM and weight was found. Lastly, the study found a greater association between CRP, age, surgical patients, and respiratory rate and a general greater than ±10% difference between measured and estimation of energy requirements.