Malnutrition and pectoralis muscle index in medical intensive care unit patients: A matched cohort study.

BACKGROUND: Muscle assessment is an important component of nutrition assessment. The Global Leadership Initiative on Malnutrition (GLIM) consortium recently underscored the need for more objective muscle assessment methods in clinical settings. Various assessment techniques are available; however, many have limitations in clinical populations. Computed tomography (CT) scans, obtained for diagnostic reasons, could serve multiple purposes, including muscle measurement for nutrition assessment. Although CT scans of the chest are commonly performed clinically, there is little research surrounding the utility of pectoralis muscle measurements in nutrition assessment. The primary aim was to determine whether CT-derived measures of pectoralis major cross-sectional area (PMA) and quality (defined as mean pectoralis major Hounsfield units [PMHU]) could be used to identify malnutrition in patients who are mechanically ventilated in an intensive care unit (ICU). A secondary aim was to evaluate the relationship between these measures and clinical outcomes in this population. METHODS: A retrospective analysis was conducted on 33 pairs of age- and sex-matched adult patients who are being mechanically ventilated in the ICU. Patients were grouped by nutrition status. Analyses were performed to determine differences in PMA and mean PMHU between groups. Associations between muscle and clinical outcomes were also investigated. RESULTS: Compared with nonmalnourished controls, malnourished patients had a significantly lower PMA (P = 0.001) and pectoralis major (PM) index (PMA/height in m2; P = 0.001). No associations were drawn between PM measures and clinical outcomes. CONCLUSION: These findings regarding CT PM measures lay the groundwork for actualizing the GLIM call to action to validate quantitative, objective muscle assessment methods in clinical settings.

Integration of quantitative methods and mathematical approaches for the modeling of cancer cell proliferation dynamics.

Physiological processes rely on the control of cell proliferation, and the dysregulation of these processes underlies various pathological conditions, including cancer. Mathematical modeling can provide new insights into the complex regulation of cell proliferation dynamics. In this review, we first examine quantitative experimental approaches for measuring cell proliferation dynamics in vitro and compare the various types of data that can be obtained in these settings. We then explore the toolbox of common mathematical modeling frameworks that can describe cell behavior, dynamics, and interactions of proliferation. We discuss how these wet-laboratory studies may be integrated with different mathematical modeling approaches to aid the interpretation of the results and to enable the prediction of cell behaviors, specifically in the context of cancer.

An Evaluation of Phylogenetic Workflows in Viral Molecular Epidemiology.

The use of viral sequence data to inform public health intervention has become increasingly common in the realm of epidemiology. Such methods typically utilize multiple sequence alignments and phylogenies estimated from the sequence data. Like all estimation techniques, they are error prone, yet the impacts of such imperfections on downstream epidemiological inferences are poorly understood. To address this, we executed multiple commonly used viral phylogenetic analysis workflows on simulated viral sequence data, modeling Human Immunodeficiency Virus (HIV), Hepatitis C Virus (HCV), and Ebolavirus, and we computed multiple methods of accuracy, motivated by transmission-clustering techniques. For multiple sequence alignment, MAFFT consistently outperformed MUSCLE and Clustal Omega, in both accuracy and runtime. For phylogenetic inference, FastTree 2, IQ-TREE, RAxML-NG, and PhyML had similar topological accuracies, but branch lengths and pairwise distances were consistently most accurate in phylogenies inferred by RAxML-NG. However, FastTree 2 was the fastest, by orders of magnitude, and when the other tools were used to optimize branch lengths along a fixed FastTree 2 topology, the resulting phylogenies had accuracies that were indistinguishable from their original counterparts, but with a fraction of the runtime.

Killed whole-genome reduced-bacteria surface-expressed coronavirus fusion peptide vaccines protect against disease in a porcine model.

As the coronavirus disease 2019 (COVID-19) pandemic rages on, it is important to explore new evolution-resistant vaccine antigens and new vaccine platforms that can produce readily scalable, inexpensive vaccines with easier storage and transport. We report here a synthetic biology-based vaccine platform that employs an expression vector with an inducible gram-negative autotransporter to express vaccine antigens on the surface of genome-reduced bacteria to enhance interaction of vaccine antigen with the immune system. As a proof-of-principle, we utilized genome-reduced Escherichia coli to express SARS-CoV-2 and porcine epidemic diarrhea virus (PEDV) fusion peptide (FP) on the cell surface, and evaluated their use as killed whole-cell vaccines. The FP sequence is highly conserved across coronaviruses; the six FP core amino acid residues, along with the four adjacent residues upstream and the three residues downstream from the core, are identical between SARS-CoV-2 and PEDV. We tested the efficacy of PEDV FP and SARS-CoV-2 FP vaccines in a PEDV challenge pig model. We demonstrated that both vaccines induced potent anamnestic responses upon virus challenge, potentiated interferon-γ responses, reduced viral RNA loads in jejunum tissue, and provided significant protection against clinical disease. However, neither vaccines elicited sterilizing immunity. Since SARS-CoV-2 FP and PEDV FP vaccines provided similar clinical protection, the coronavirus FP could be a target for a broadly protective vaccine using any platform. Importantly, the genome-reduced bacterial surface-expressed vaccine platform, when using a vaccine-appropriate bacterial vector, has potential utility as an inexpensive, readily manufactured, and rapid vaccine platform for other pathogens.

Intubation Barotrauma and/or CPR Causing Tension Pneumoperitoneum.

BACKGROUND: Review the radiologic findings and clinical significance of tension pneumoperitoneum. CASE REPORT: Imaging case presented to radiology during patient's prolonged and complicated hospital stay. CONCLUSIONS: Tension pneumoperitoneum associated with barotrauma is a rare, but potentially life threatening complication of mechanical ventilation. The radiologist should be able to recognize the imaging findings associated with tension pneumoperitoneum in order to assist in diagnosis of this potentially reversible entity.

Posttraumatic stress disorder in migraine.

OBJECTIVE: To evaluate the relative frequency of posttraumatic stress disorder (PTSD) in episodic migraine (EM) and chronic daily headache (CDH) sufferers and the impact on headache-related disability. BACKGROUND: Approximately 8% of the population is estimated to have PTSD. Recent studies suggest a higher frequency of PTSD in headache disorders. The association of PTSD and headache-related disability has not been examined. METHODS: A prospective study was conducted at 6 headache centers. PTSD was assessed using the life events checklist and PTSD checklist, civilian version (PCL-C). We compared data from EM to CDH, and migraine with PTSD to migraine without PTSD. The PHQ-9 was used to assess depression, and headache impact test (HIT-6) to assess disability. RESULTS: Of 767 participants, 593 fulfilled criteria for EM or CDH and were used in this analysis. The mean age was 42.2 years and 92% were women. The frequency of PTSD was greater in CDH than in EM (30.3% vs 22.4%, P = .043), but not after adjusting for demographics and depression (P = .87). However, participants with major depression and PTSD were more likely to have CDH than EM (24.6% vs 15.79%, P < .002). Disability was greater in migraineurs with PTSD, even after adjustments (65.2 vs 61.7, P = .002). CONCLUSION: The frequency of PTSD in migraineurs, whether episodic or chronic, is higher than the historically reported prevalence of PTSD in the general population. In addition, in the subset of migraineurs with depression, PTSD frequency is greater in CDH sufferers than in episodic migraineurs. Finally, the presence of PTSD is independently associated with greater headache-related disability in migraineurs.

Post-traumatic stress disorder in episodic and chronic migraine.

OBJECTIVE: To assess and contrast the relative frequency of self-reported post-traumatic stress disorder (PTSD) in patients with episodic migraine and chronic/ transformed migraine. BACKGROUND: Several risk factors have been identified as risk factors for chronification of headache disorders. Childhood abuse has been suggested as a risk factor for chronic pain in adulthood. In addition depression, as well as several other psychiatric disorders, are co-morbid with migraine. Recent data suggest that PTSD may be more common in headache sufferers than in the general population. METHODS: This was a prospective, pilot study conducted at a headache center. Adult subjects with episodic, chronic, or transformed migraine were included. Demographic information, depression history, body mass index (BMI), and headache characteristics were obtained. PTSD was assessed using the life events checklist (LEC) and the PTSD checklist, civilian version (PCL-C). We contrasted the data from episodicmigraineurs and chronic/transformed migraine participants (CM) and conducted multivariate analyses, adjusting for covariates. RESULTS: Of the 60 participants included, 91.7% were female with a mean age of 41.4+/-12.5 years old. EM was diagnosed in 53.3% and CM in 46.7%. The mean BMI was not significantly different between groups. In contrast, the relative frequency of depression was significantly greater in subjects with CM (55.2%) than EM (21.9%, P=.016). There was no significant difference in the percentage of participants reporting at least 1 significant traumatic life event (LE) or in the mean number of traumatic LEs between EM and CM participants. However, the relative frequency of PTSD reported on the PCL in CM (42.9%) was significantly greater as compared to EM (9.4%, P=.0059. After adjusting for depression and other potential confounders, the difference remained significant P=.023). CONCLUSION: PTSD is more common in CM than in episodic migraineurs. This suggests that PTSD may be a risk factor for headache chronification, pending longitudinal studies to test this hypothesis.