Association between Age and Mortality in Pediatric and Adult Acute Respiratory Distress Syndrome.

Rationale: The epidemiology, management, and outcomes of acute respiratory distress syndrome (ARDS) differ between children and adults, with lower mortality rates in children despite comparable severity of hypoxemia. However, the relationship between age and mortality is unclear.Objective: We aimed to define the association between age and mortality in ARDS, hypothesizing that it would be nonlinear.Methods: We performed a retrospective cohort study using data from two pediatric ARDS observational cohorts (n = 1,236), multiple adult ARDS trials (n = 5,547), and an adult observational ARDS cohort (n = 1,079). We aligned all datasets to meet Berlin criteria. We performed unadjusted and adjusted logistic regression using fractional polynomials to assess the potentially nonlinear relationship between age and 90-day mortality, adjusting for sex, PaO2/FiO2, immunosuppressed status, year of study, and observational versus randomized controlled trial, treating each individual study as a fixed effect.Measurements and Main Results: There were 7,862 subjects with median ages of 4 years in the pediatric cohorts, 52 years in the adult trials, and 61 years in the adult observational cohort. Most subjects (43%) had moderate ARDS by Berlin criteria. Ninety-day mortality was 19% in the pediatric cohorts, 33% in the adult trials, and 67% in the adult observational cohort. We found a nonlinear relationship between age and mortality, with mortality risk increasing at an accelerating rate between 11 and 65 years of age, after which mortality risk increased more slowly.Conclusions: There was a nonlinear relationship between age and mortality in pediatric and adult ARDS.

Evolution of distal limb perfusion management in adult peripheral venoarterial extracorporeal membrane oxygenation with femoral artery cannulation.

Limb ischaemia is a clinically relevant complication of venoarterial extracorporeal membrane oxygenation (VA ECMO) with femoral artery cannulation. No selective distal perfusion or other advanced techniques were used in the past to maintain adequate distal limb perfusion. A more recent trend is the shift from the reactive or emergency management to the pro-active or prophylactic placement of a distal perfusion cannula to avoid or reduce limb ischaemia-related complications. Multiple alternative cannulation techniques to the distal perfusion cannula have been developed to maintain distal limb perfusion, including end-to-side grafting, external or endovascular femoro-femoral bypass, retrograde limb perfusion (e.g., via the posterior tibial, dorsalis pedis or anterior tibial artery), and, more recently, use of a bidirectional cannula. Venous congestion has also been recognized as a potential contributing factor to limb ischaemia development and specific techniques have been described with facilitated venous drainage or bilateral cannulation being the most recent, to reduce or avoid venous stasis as a contributor to impaired limb perfusion. Advances in monitoring techniques, such as near-infrared spectroscopy and duplex ultrasound analysis, have been applied to improve decision-making regarding both the monitoring and management of limb ischaemia. This narrative review describes the evolution of techniques used for distal limb perfusion during peripheral VA ECMO.

A Brief Review of Inpatient Palliative Rehabilitation.

Cancer patients face many challenges that can have a significant impact on their quality of life (QOL). When patients experience multiple functional impairments due to disease or treatment, their QOL and the efficient use of healthcare resources can be compromised. This is particularly true for patients who are nearing the end of their lives, as the physical and emotional burden of cancer can have a profound effect on both the individual and their caregivers. One approach to improving QOL in these patients is through palliative rehabilitation. Despite being an underutilized and understudied resource, palliative rehabilitation has shown promise in helping patients with advanced cancer retain their dignity and sense of control. By maximizing functional independence and reducing symptom burdens, palliative rehabilitation can provide a vital source of support for patients and their caregivers during this challenging time. Inpatient rehabilitation is one way that palliative rehabilitation can be applied in a healthcare setting. While further research is needed to fully understand the benefits of this approach, it is clear that palliative rehabilitation has the potential to play a key role in helping patients and their caregivers navigate the challenges of cancer treatment and end-of-life care. This approach is specific to the USA context but can be applied in other settings where cancer patients require such care.

Agreement Between Peak Inspiratory Pressure in Decelerating-Flow Ventilation and Plateau Pressure in Square-Flow Ventilation in Pediatric Acute Respiratory Distress Syndrome.

OBJECTIVES: Acute respiratory distress syndrome guidelines suggest limiting plateau pressures to 28-30 cm H2O. Plateau pressure is most accurately measured in square-flow modes, such as volume control. In children, decelerating-flow modes, such as pressure-regulated volume control and pressure control, are more common. Consequently, plateau pressures are rarely obtained, and pressure limits are instead provided for peak inspiratory pressure. The degree to which peak inspiratory pressure in decelerating-flow overestimates plateau pressure is unknown. Therefore, we assessed the correlation and accuracy of peak inspiratory pressure in decelerating-flow ventilation for approximating plateau pressure during square-flow ventilation. DESIGN: Prospective, observational study. SETTING: Tertiary, academic PICU. PATIENTS: Fifty-two intubated children with acute respiratory distress syndrome enrolled between January 2020 and May 2021. INTERVENTIONS: Measurement of peak inspiratory pressure in decelerating-flow ventilation and plateau pressure after transition to square-flow ventilation. MEASUREMENTS AND MAIN RESULTS: Peak inspiratory pressure in decelerating-flow was highly correlated (r2 = 0.99; p < 0.001) with plateau pressure in square-flow. Peak inspiratory pressure was 1.0 ± 0.6 cm H2O higher than plateau pressure, with 96% of values within 2 cm H2O. The single outlier had coexistent asthma and inspiratory flows that did not reach zero. CONCLUSIONS: Peak inspiratory pressure measured during decelerating-flow ventilation may be an adequate surrogate of plateau pressure in pediatric acute respiratory distress syndrome when inspiratory flow approaches zero. Practitioners should be aware that peak inspiratory pressures in decelerating-flow may not be substantially higher than plateau pressures.

Biomechanical constitutive modeling of the gastrointestinal tissues: a systematic review.

The gastrointestinal (GI) tract is a continuous channel through the body that consists of the esophagus, the stomach, the small intestine, the large intestine, and the rectum. Its primary functions are to move the intake of food for digestion before storing and ultimately expulsion of feces. The mechanical behavior of GI tissues thus plays a crucial role for GI function in health and disease. The mechanical properties are characterized by a biomechanical constitutive model, which is a mathematical representation of the relation between load and deformation in a tissue. Hence, validated biomechanical constitutive models are essential to characterize and simulate the mechanical behavior of the GI tract. Here, a systematic review of these constitutive models is provided. This review is limited to studies where a model of the strain energy function is proposed to characterize the stress-strain relation of a GI tissue. Several needs are identified for more advanced modeling including: 1) Microstructural models that provide actual structure-function relations; 2) Validation of coupled electro-mechanical models accounting for active muscle contractions; 3) Human data to develop and validate models. The findings from this review provide guidelines for using existing constitutive models as well as perspective and directions for future studies.

Total vascular resistance increases during volume-unloading in asymptomatic single ventricle patients.

OBJECTIVE: While the surgical stages of single ventricle (SV) palliation serve to separate pulmonary venous and systemic venous return, and to volume-unload the SV, staged palliation also results in transition from parallel to series circulation, increasing total vascular resistance. How this transition affects pressure loading of the SV is as yet unreported. METHODS: We performed a retrospective chart review of Stage I, II, and III cardiac catheterization (CC) and echocardiographic data from 2001-2017 in all SV pts, with focus on systemic, pulmonary, and total vascular resistance (SVR, PVR, TVR respectively). Longitudinal analyses were performed with log-transformed variables. Effects of SVR-lowering medications were analyzed using Wilcoxon rank-sum testing. RESULTS: There were 372 total patients who underwent CC at a Stage I (median age of 4.4 months, n=310), Stage II (median age 2.7 years, n = 244), and Stage III (median age 7.3 years, n = 113). Total volume loading decreases with progression to Stage III (P< 0.001). While PVR gradually increases from Stage II to Stage III, and SVR increases from Stage I to Stage III, TVR dramatically increases with progress towards series circulation. TVR was not affected by use of systemic vasodilator therapy. TVR, PVR, SVR, and CI did not correlate with indices of SV function at Stage III. CONCLUSIONS: TVR steadily increases with an increasing contribution from SVR over progressive stages. TVR was not affected by systemic vasodilator agents. TVR did not correlate with echo-based indices of SV function. Further studies are needed to see if modulating TVR can improve exercise tolerance and outcomes.

A sensitive HPLC-MS/MS method for the detection, resolution and quantitation of cathinone enantiomers in horse blood plasma and urine.

Resolution of cathinone enantiomers in equine anti-doping analysis is becoming more important to distinguish the inadvertent ingestion of plant-based products from those of deliberate administration of designer synthetic analogs. With this in mind, a rapid and sensitive method was developed and validated for the detection, resolution and quantitative determination of cathinone enantiomers in horse blood plasma and urine. The analytes were recovered from the blood plasma and urine matrices by using a liquid-liquid extraction after adjusting the pH to 9. The recovered analytes were derivatized with Nα-(2,4-dinitro-5-fluorophenyl)-L-valinamide, a chiral derivatizing agent analogous to Marfey's reagent. The resulting diastereoisomers were baseline resolved under a reversed-phase liquid chromatographic condition. Derivatization of the analytes not only allowed the separation of the enantiomers using cost-effective traditional liquid chromatography conditions and reversed-phase columns but also increased the sensitivity, at least to an order of magnitude, when tandem mass spectrometry is used for the detection. A limit of detection of 0.05 ng/mL was achieved for cathinone enantiomers for both matrices. Acceptable intraday and interday precision and accuracy along with satisfactory dilution accuracy and precision were observed during the method validation. The method suitability was tested using the post administration urine samples collected after single doses of cathinone and ephedrine as single-enantiomeric form and methcathinone as racemic form. Finally, a proof of concept of the isomeric ratio in urine samples to distinguish the presence of cathinone as a result of accidental ingestion of plant-based product from that of an illicit use of a designer product is demonstrated. To the best of our knowledge, this is the first such work where cathinone enantiomers were resolved and quantified in horse blood plasma and urine at sub nanogram levels.

Whole Blood for Civilian Urban Trauma Resuscitation: Historical, Present, and Future Considerations.

Whole blood (WB) has been used for more than a century for far-forward combat resuscitation. Following the Iraq/Afghanistan combat, maritime, and austere environment use of WB for the resuscitation of severely hemorrhaging patients, there has been an increasing use of WB for the civilian urban resuscitation environment population. The impetus for this was not just improved outcomes in far-forward hospitals, which had different populations and different needs than the civilian urban population, but also an application of the lessons suggested by recent 1:1:1 plasma:platelets:packed red cells fixed-ratio studies for patients with massive transfusion needs. Mechanistic, logistic, and standardization concerns have been addressed and are evolving as the WB project advances. A small number of studies have been published on WB in the civilian urban trauma population. In addition, European experience with viscoelastic testing and resuscitation with fibrinogen and prothrombin complex concentrate has provided another viewpoint regarding the choice of resuscitation strategies for severely bleeding trauma patients in urban civilian environments. There are randomized controlled trials in process, which are testing the hypothesis that WB may be beneficial for the civilian urban population. Whether WB will improve mortality significantly is now a matter of intense study, and this commentary reviews the history, mechanistic foundations, and logistical aspects for the use of WB in the civilian trauma population.

A toxicogenomic approach for the risk assessment of the food contaminant acetamide.

Acetamide (CAS 60-35-5) is detected in common foods. Chronic rodent bioassays led to its classification as a group 2B possible human carcinogen due to the induction of liver tumors in rats. We used a toxicogenomics approach in Wistar rats gavaged daily for 7 or 28 days at doses of 300 to 1500 mg/kg/day (mkd) to determine a point of departure (POD) and investigate its mode of action (MoA). Ki67 labeling was increased at doses ≥750 mkd up to 3.3-fold representing the most sensitive apical endpoint. Differential gene expression analysis by RNA-Seq identified 1110 and 1814 differentially expressed genes in male and female rats, respectively, following 28 days of treatment. Down-regulated genes were associated with lipid metabolism while up-regulated genes included cell signaling, immune response, and cell cycle functions. Benchmark dose (BMD) modeling of the Ki67 labeling index determined the BMD10 lower confidence limit (BMDL10) as 190 mkd. Transcriptional BMD modeling revealed excellent concordance between transcriptional POD and apical endpoints. Collectively, these results indicate that acetamide is most likely acting through a mitogenic MoA, though specific key initiating molecular events could not be elucidated. A POD value of 190 mkd determined for cell proliferation is suggested for risk assessment purposes.

Managing the Rehabilitation Wave: Rehabilitation Services for COVID-19 Survivors.

The coronavirus disease 2019 (COVID-19) pandemic is having a profound effect on the provision of medical care. As the curve progresses and patients are discharged, the rehabilitation wave brings a high number of postacute COVID-19 patients suffering from physical, mental, and cognitive impairments threatening their return to normal life. The complexity and severity of disease in patients recovering from severe COVID-19 infection require an approach that is implemented as early in the recovery phase as possible, in a concerted and systematic way. To address the rehabilitation wave, we describe a spectrum of interventions that start in the intensive care unit and continue through all the appropriate levels of care. This approach requires organized rehabilitation teams including physical therapists, occupational therapists, speech-language pathologists, rehabilitation psychologists or neuropsychologists, and physiatrists collaborating with acute medical teams. Here, we also discuss administrative factors that influence the provision of care during the COVID-19 pandemic. The services that can be provided are described in detail to allow the reader to understand what services may be appropriate locally. We have been learning and adapting real time during this crisis and hope that sharing our experience facilitates the work of others as the pandemic evolves. It is our goal to help reduce the potentially long-lasting challenges faced by COVID-19 survivors.

Reversible cardiac dysfunction in severe COVID-19 infection, mechanisms and case report.

A previously healthy 49-year-old male patient presented with COVID-19 infection and required mechanical ventilation and extracorporeal membrane oxygenation due to severe hypoxemia. Echocardiography showed cardiac dysfunction with an apical sparing strain pattern, which rapidly normalized within a week. Apical sparing myocardial strain in patients with COVID-19 infection may suggest reverse-type stress cardiomyopathy.

Length-Selective Synthesis of Acylglycerol-Phosphates through Energy-Dissipative Cycling.

The main aim of origins of life research is to find a plausible sequence of transitions from prebiotic chemistry to nascent biology. In this context, understanding how and when phospholipid membranes appeared on early Earth is critical to elucidating the prebiotic pathways that led to the emergence of primitive cells. Here we show that exposing glycerol-2-phosphate to acylating agents leads to the formation of a library of acylglycerol-phosphates. Medium-chain acylglycerol-phosphates were found to self-assemble into vesicles stable across a wide range of conditions and capable of retaining mono- and oligonucleotides. Starting with a mixture of activated carboxylic acids of different lengths, iterative cycling of acylation and hydrolysis steps allowed for the selection of longer-chain acylglycerol-phosphates. Our results suggest that a selection pathway based on energy-dissipative cycling could have driven the selective synthesis of phospholipids on early Earth.

Novel swine model of colonic diverticulosis.

The pathophysiology of colonic diverticulosis has not been completely understood. The development of appropriate animal models is essential to study diverticular disease. To date, no large animal models are available for this disease condition. The objective of this study was to develop a swine model by damaging the colon wall, combined with or without a low-fiber diet to mimic the pathogenesis of diverticulosis. To create a weakness on the colon wall, collagenase was applied in vivo to degrade the collagen in the colon wall. Three groups of Yucatan minipigs were included. Group 1 (n = 12) underwent collagenase injection (CI) with a low-fiber diet for 6 mo, group 2 (n = 8) underwent CI alone with a standard swine diet for 6 mo, and group 3 (n = 12) received a low-fiber diet alone for 6 mo. We found that diverticulosis occurred in 91.7% (11 of 12) of pigs in the CI + diet group and 100% (8 of 8) in CI-alone group. Moreover, around 30-75% of colon CI spots for each pig developed diverticular lesions. Diet alone for 6 mo did not induce diverticulosis. The endoscopic and histological examinations revealed the formation of multiple wide-mouthed diverticular lesions along the descending colon. Our results provide convincing evidence of the high efficacy of the reduced colon wall strength caused by CI in the development of a swine model of diverticulosis. Low-fiber diet consumption for 6 mo had no influence on the generation time or incidence rate of diverticulosis. In this model, digestion of the collagen in the colonic wall is sufficient to cause diverticulosis. NEW & NOTEWORTHY Effective large animal models of diverticulosis are currently lacking for the study of diverticular disease. This study marks the first time that a swine model of diverticulosis was developed by damaging colon wall structure, combined with or without a low-fiber diet. We found that a defect of colon wall could result in colon diverticular lesions within 6 mo in swine. This animal model mimicking the pathological process of diverticulosis is of great clinical value.

Mutations in sorghum SBEIIb and SSIIa affect alkali spreading value, starch composition, thermal properties and flour viscosity.

KEY MESSAGE: Seven novel alleles of SBEIIb and one allele of SSIIa co-segregated with the ASV phenotype and contributed to distinct starch quality traits important for food-processing applications. Sorghum is an important food crop for millions of people in Africa and Asia. Whole-genome re-sequencing of sorghum EMS mutants exhibiting an alkali spreading value (ASV) phenotype revealed candidate SNPs in Sobic.004G163700 and Sobic.010G093400. Comparative genomics identified Sobic.010G093400 as a starch synthase IIa and Sobic.004G163700 as a starch branching enzyme IIb. Segregation analyses showed that mutations in Sobic.010G093400 or Sobic.004G163700 co-segregated with the ASV phenotype. Mutants in SSIIa exhibited no change in amylose content but expressed lower final viscosity and lower starch gelatinization temperature (GT) than starches from non-mutant plants. The sbeIIb mutants exhibited significantly higher amylose levels and starch GT and lower viscosity compared to non-mutant starches and ssIIa mutants. Mutations in SBEIIb had a dosage-dependent effect on amylose content. Double mutants of sbeIIb and ssIIa resembled their sbeIIb parent in amylose content, starch thermal properties and viscosity profiles. These variants will provide opportunities to produce sorghum varieties with modified starch end-use qualities important for the beer brewing and baking industries and specialty foods for humans with diabetes.

Green synthesis, biological evaluation, molecular docking studies and 3D-QSAR analysis of novel phenylalanine linked quinazoline-4(3H)-one-sulphonamide hybrid entities distorting the malarial reductase activity in folate pathway.

A modified Grimmel's method for N-heterocyclization of phenylalanine linked sulphonamide side arm at position-2 was optimized leading to 2,3-disustituted-4-quinazolin-(3H)-ones. Further, [Bmim][BF4]-H2O (IL) was used as green solvent as well as catalyst for the synthesis of twenty two hybrid quinazolinone motifs (4a-4v) by N-heterocyclization reaction using microwave irradiation technique. The in vitro screening of the hybrid entities against the malarial species Plasmodium falciparum yielded five potent molecules 4l, 4n, 4r, 4t & 4u owing comparable antimalarial activity to the reference drugs. In continuation, anin silicostudy was carried out to obtain a pharmacophoric model and quantitative structure activity relationship. We also built a 3D-QSAR model to procure more information that could be applied to design new molecules with more potent Pf-DHFR inhibitory activity. The designed pharmacophore was recognized to be more potent for the selected molecules, exhibiting five pharmacophoric features. The active scaffolds were further evaluated for enzyme inhibition efficacy against alleged receptor Pf-DHFR computationally and in vitro, proving their candidature as lead dihydrofolate reductase inhibitors as well as the selectivity of the test candidates was ascertained by toxicity study against vero cells. The perception of good oral bioavailability was also proved by study of pharmacokinetic properties.

Design and synthesis of leucine-linked quinazoline-4(3H)-one-sulphonamide molecules distorting malarial reductase activity in the folate pathway.

Optimization of a modified Grimmel's method for N-heterocyclization of a leucine-linked sulfonamide side-arm at position 2 leading to 2,3-disustituted-4-quinazolin-(3H)-ones was accomplished. Further, 22 hybrid quinazolinone motifs (4a-v) were synthesized by N-heterocyclization reaction under microwave irradiation using the ionic liquid [Bmim][BF4 ]-H2 O as green solvent as well as the catalyst. The in vitro screening of the hybrid entities against the malarial species Plasmodium falciparum yielded five potent molecules 4l, 4n, 4o, 4t, and 4u owning antimalarial activity comparable to those of the reference drugs. In continuation, an in silico study was carried out to obtain a pharmacophoric model and quantitative structure-activity relationship. We also built a 3D-QSAR model to procure more information that could be applied to design new molecules with more potent Pf-DHFR inhibitory activity. The designed pharmacophore was recognized to be more potent for the selected molecules, exhibiting five pharmacophoric features. The active scaffolds were further evaluated for enzyme inhibition efficacy against alleged receptor Pf-DHFR computationally and in vitro, proving their candidature as lead dihydrofolate reductase inhibitors, and the selectivity of the test candidates was ascertained by toxicity study against Vero cells. Good oral bioavailability was also proved by studying pharmacokinetic properties.

Annular Pancreas in Adults: Case Report and Literature Review.

Annular pancreas is an uncommon congenital cause of gastric outlet obstruction. The incidence is usually referenced at between five and 15 per 100,000 based on autopsy series. When present, this rare condition surfaces with symptoms in the pediatric population during the first few months of life. An adult presenting with symptoms of gastric outlet obstruction due to annular pancreas is an unusual incident. This case describes gastric outlet obstruction due to a partial annular pancreatic band in an otherwise healthy 32-year-old male. Given the scarcity of this pathological process in adults; no specific guidelines exist about the management of this condition. Continued reporting of this pathology is essential for development of such guidelines. Literature review, embryology and treatment options will be discussed.

Animal Models of Diverticulosis: Review and Recommendations.

Diverticulosis is a structural alteration of the colon tissue characterized by the development of pouch-like structures called diverticula. It afflicts a significant portion of the population in Western countries, with a higher prevalence among the elderly. Diverticulosis is believed to be the result of a synergetic interaction between inherent tissue weakness, diet, colonic microstructure, motility, and genetic factors. A validated etiology has, however, not yet been established. Non-surgical treatment is currently lacking due to this poor understanding, and surgical colon resection is the only long-term solution following recurrent complications. With rising prevalence, the burden of diverticulosis on patients and hospital resources has increased over the past several years. More efficient and less invasive treatment approaches are, thus, urgently needed. Animal models of diverticulosis are crucial to enable a preclinical assessment and evaluation of such novel approaches. This review discusses the animal models of diverticulosis that have been proposed to date. The current models require either a significant amount of time to develop diverticulosis, present a relatively low success rate, or seriously deteriorate the animals' systemic health. Recommendations are thus provided to address these pitfalls through the selection of a suitable animal and the combination of multiple risk factors for diverticulosis.

Physician-Assisted Suicide and Euthanasia in the ICU: A Dialogue on Core Ethical Issues.

OBJECTIVE: Many patients are admitted to the ICU at or near the end of their lives. Consequently, the increasingly common debate regarding physician-assisted suicide and euthanasia holds implications for the practice of critical care medicine. The objective of this article is to explore core ethical issues related to physician-assisted suicide and euthanasia from the perspective of healthcare professionals and ethicists on both sides of the debate. SYNTHESIS: We identified four issues highlighting the key areas of ethical tension central to evaluating physician-assisted suicide and euthanasia in medical practice: 1) the benefit or harm of death itself, 2) the relationship between physician-assisted suicide and euthanasia and withholding or withdrawing life support, 3) the morality of a physician deliberately causing death, and 4) the management of conscientious objection related to physician-assisted suicide and euthanasia in the critical care setting. We present areas of common ground and important unresolved differences. CONCLUSIONS: We reached differing positions on the first three core ethical questions and achieved unanimity on how critical care clinicians should manage conscientious objections related to physician-assisted suicide and euthanasia. The alternative positions presented in this article may serve to promote open and informed dialogue within the critical care community.