Vaccines are urgently needed to combat the global coronavirus disease 2019 (COVID-19) pandemic, and testing of candidate vaccines in an appropriate non-human primate (NHP) model is a critical step in ...the process. Infection of African green monkeys (AGM) with a low passage human isolate of SARS-CoV-2 by aerosol or mucosal exposure resulted in mild clinical infection with a transient decrease in lung tidal volume. Imaging with human clinical-grade 18F-fluoro-2-deoxy-D-glucose positron emission tomography (18F-FDG PET) co-registered with computed tomography (CT) revealed pulmonary lesions at 4 days post-infection (dpi) that resolved over time. Infectious virus was shed from both respiratory and gastrointestinal (GI) tracts in all animals in a biphasic manner, first between 2-7 dpi followed by a recrudescence at 14-21 dpi. Viral RNA (vRNA) was found throughout both respiratory and gastrointestinal systems at necropsy with higher levels of vRNA found within the GI tract tissues. All animals seroconverted simultaneously for IgM and IgG, which has also been documented in human COVID-19 cases. Young AGM represent an species to study mild/subclinical COVID-19 disease and with possible insights into live virus shedding. Future vaccine evaluation can be performed in AGM with correlates of efficacy being lung lesions by PET/CT, virus shedding, and tissue viral load.
There is an urgent and unmet need for new antifungal therapies. Global fungal infection rates continue to rise and fungal infections pose increasing burdens on global healthcare systems. Exacerbating ...the situation, the available antifungal therapeutic arsenal is limited and development of new antifungals has been slow. Current antifungals are known for unwanted side effects including nephrotoxicity and hepatotoxicity. Thus, the need for new antifungals and new antifungal targets is urgent and growing. A collection of 60 commercially-available essential oils has been screened for antifungal activity against
,
, and
, as well as for cytotoxic activity against MCF-7 and MDA-MB-231 human breast tumor cell lines; the chemical compositions of the essential oils have been determined by gas chromatography-mass spectrometry (GC-MS). Ten essential oils showed remarkable antifungal and cytotoxic activities: Indian, Australian, and Hawaiian sandalwoods; melissa; lemongrass; cilantro; cassia; cinnamon; patchouli; and vetiver.
Since SARS-CoV-2 emerged in late 2019, it spread from China to the rest of the world. An initial concern was the potential for vaccine- or antibody-dependent enhancement (ADE) of disease as had been ...reported with other coronaviruses. To evaluate this, we first developed a ferret model by exposing ferrets to SARS-CoV-2 by either mucosal inoculation (intranasal/oral/ocular) or inhalation using a small particle aerosol. Mucosal inoculation caused a mild fever and weight loss that resolved quickly; inoculation via either route resulted in virus shedding detected in the nares, throat, and rectum for 7–10 days post-infection. To evaluate the potential for ADE, we then inoculated groups of ferrets intravenously with 0.1, 0.5, or 1 mg/kg doses of a human polyclonal anti-SARS-CoV-2 IgG from hyper-immunized transchromosomic bovines (SAB-185). Twelve hours later, ferrets were challenged by mucosal inoculation with SARS-CoV-2. We found no significant differences in fever, weight loss, or viral shedding after infection between the three antibody groups or the controls. Signs of pathology in the lungs were noted in infected ferrets but no differences were found between control and antibody groups. The results of this study indicate that healthy, young adult ferrets of both sexes are a suitable model of mild COVID-19 and that low doses of specific IgG in SAB-185 are unlikely to enhance the disease caused by SARS-CoV-2.
Sepsis is a frequently lethal state, commonly associated with left ventricular (LV) dysfunction. Right ventricular (RV) dysfunction in sepsis is less well understood.
In septic patients, how common ...is RV dysfunction, and is it associated with worse outcomes?
We measured echocardiographic parameters on critically ill patients with severe sepsis or septic shock within the first 24 hours of ICU admission. We defined RV dysfunction as fractional area change (FAC) less than 35% or tricuspid annulus systolic plane excursion (TAPSE) less than 1.6 cm. We defined LV systolic dysfunction as ejection fraction (EF) less than 45% or longitudinal strain greater than -19%. Using logistic regression, we assessed the relationship between 28-day mortality and presence of RV dysfunction and LV systolic dysfunction, controlling for receipt of vasopressors, receipt of fluid, mechanical ventilation, and the acute physiology and chronic health evaluation (APACHE II) score.
We studied 393 patients. RV and LV dysfunction were common (48% and 63%, respectively). Mean echocardiographic values were: RV end-diastolic area, 22.4 ± 7.0 cm2; RV end-systolic area, 14.2 ± 6.0 cm2; RV FAC, 38 ± 11%; TAPSE, 1.8 ± .06 cm; RV longitudinal strain, -15.3 ± 6.5%; LV EF, 60% ± 14%; LV longitudinal strain, -16.5% ± 6.0%. Patients with RV dysfunction had higher 28-day mortality (31% vs 16%, P = .001). In our multivariable regression model, RV dysfunction was associated with increased mortality (OR, 3.4; CI, 1.7-6.8; P = .001), and LV systolic dysfunction was not (OR, 0.63; CI, 0.3 -1.2; P = .32)
Right ventricular dysfunction is present in nearly half of studied septic patients and is associated with over threefold higher 28-day mortality.
The diseases caused by the Bartonella genus of bacteria are clinically diverse, and can be challenging to cure. The study of bartonellosis has been hampered by the lack of a suitable animal model. ...Preclinical studies for novel therapeutics and a competent host for vector transmission studies are needed to fill critical knowledge gaps. The studies included here are a representation of in vivo Bartonella research and the corresponding challenges. This review examines the current state of available animal models by assessing the success of various model species and strains in Bartonella infection. With a focus on the strengths and weaknesses of current animal models, the importance of these models for improvement of human health and veterinary care is emphasized.
Left ventricular diastolic dysfunction is common in patients with severe sepsis or septic shock, but the best approach to categorization is unknown. We assessed the association of common measures of ...diastolic function with clinical outcomes and tested the utility of a simplified definition of diastolic dysfunction against the American Society of Echocardiography (ASE) 2009 definition.
In this prospective observational study, patients with severe sepsis or septic shock underwent transthoracic echocardiography within 24 h of onset of sepsis (median 4.3 h). We measured echocardiographic parameters of diastolic function and used random forest analysis to assess their association with clinical outcomes (28-day mortality and ICU-free days to day 28) and thereby suggest a simplified definition. We then compared patients categorized by the ASE 2009 definition and our simplified definition.
We studied 167 patients. The ASE 2009 definition categorized only 35 % of patients. Random forest analysis demonstrated that the left atrial volume index and deceleration time, central to the ASE 2009 definition, were not associated with clinical outcomes. Our simplified definition used only e' and E/e', omitting the other measurements. The simplified definition categorized 87 % of patients. Patients categorized by either ASE 2009 or our novel definition had similar clinical outcomes. In both definitions, worsened diastolic function was associated with increased prevalence of ischemic heart disease, diabetes, and hypertension.
A novel, simplified definition of diastolic dysfunction categorized more patients with sepsis than ASE 2009 definition. Patients categorized according to the simplified definition did not differ from patients categorized according to the ASE 2009 definition in respect to clinical outcome or comorbidities.
Traumatic brain injury (TBI) is a major cause of disability worldwide, but the heterogeneous nature of TBI with respect to injury severity and health comorbidities make patient outcome difficult to ...predict. Injury severity accounts for only some of this variance, and a wide range of preinjury, injury‐related, and postinjury factors may influence outcome, such as sex, socioeconomic status, injury mechanism, and social support. Neuroimaging research in this area has generally been limited by insufficient sample sizes. Additionally, development of reliable biomarkers of mild TBI or repeated subconcussive impacts has been slow, likely due, in part, to subtle effects of injury and the aforementioned variability. The ENIGMA Consortium has established a framework for global collaboration that has resulted in the largest‐ever neuroimaging studies of multiple psychiatric and neurological disorders. Here we describe the organization, recent progress, and future goals of the Brain Injury working group.
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Traumatic brain injury (TBI) often results in traumatic axonal injury and white matter (WM) damage, particularly to the corpus callosum (CC). Damage to the CC can lead to impaired performance on ...neurocognitive tasks, but there is a high degree of heterogeneity in impairment following TBI. Here we examined the relation between CC microstructure and function in pediatric TBI. We used high angular resolution diffusion-weighted imaging (DWI) to evaluate the structural integrity of the CC in humans following brain injury in a sample of 32 children (23 males and 9 females) with moderate-to-severe TBI (msTBI) at 1-5 months postinjury, compared with well matched healthy control children. We assessed CC function through interhemispheric transfer time (IHTT) as measured using event-related potentials (ERPs), and related this to DWI measures of WM integrity. Finally, the relation between DWI and IHTT results was supported by additional results of neurocognitive performance assessed using a single composite performance scale. Half of the msTBI participants (16 participants) had significantly slower IHTTs than the control group. This slow IHTT group demonstrated lower CC integrity (lower fractional anisotropy and higher mean diffusivity) and poorer neurocognitive functioning than both the control group and the msTBI group with normal IHTTs. Lower fractional anisotropy-a common sign of impaired WM-and slower IHTTs also predicted poor neurocognitive function. This study reveals that there is a subset of pediatric msTBI patients during the post-acute phase of injury who have markedly impaired CC functioning and structural integrity that is associated with poor neurocognitive functioning.
Traumatic brain injury (TBI) is the primary cause of death and disability in children and adolescents. There is considerable heterogeneity in postinjury outcome, which is only partially explained by injury severity. Imaging biomarkers may help explain some of this variance, as diffusion weighted imaging is sensitive to the white matter disruption that is common after injury. The corpus callosum (CC) is one of the most commonly reported areas of disruption. In this multimodal study, we discovered a divergence within our pediatric moderate-to-severe TBI sample 1-5 months postinjury. A subset of the TBI sample showed significant impairment in CC function, which is supported by additional results showing deficits in CC structural integrity. This subset also had poorer neurocognitive functioning. Our research sheds light on postinjury heterogeneity.
We examined the relationship between trimester of SARS-CoV-2 infection, illness severity, and risk for preterm birth.
We analyzed data for 6336 pregnant persons with SARS-CoV-2 infection in 2020 in ...the United States. Risk ratios for preterm birth were calculated for illness severity, trimester of infection, and illness severity stratified by trimester of infection adjusted for age, selected underlying medical conditions, and pregnancy complications.
Pregnant persons with critical COVID-19 or asymptomatic infection, compared to mild COVID-19, in the second or third trimester were at increased risk of preterm birth. Pregnant persons with moderate-to-severe COVID-19 did not show increased risk of preterm birth in any trimester.
Critical COVID-19 in the second or third trimester was associated with increased risk of preterm birth. This finding can be used to guide prevention strategies, including vaccination, and inform clinical practices for pregnant persons.
Abstract
This study investigated how proactive and reactive cognitive control processing in the brain was associated with habitual sleep health. BOLD fMRI data were acquired from 81 healthy adults ...with normal sleep (41 females, age 20.96–39.58 years) during a test of cognitive control (Not-X-CPT). Sleep health was assessed in the week before MRI scanning, using both objective (actigraphy) and self-report measures. Multiple measures indicating poorer sleep health—including later/more variable sleep timing, later chronotype preference, more insomnia symptoms, and lower sleep efficiency—were associated with stronger and more widespread BOLD activations in fronto-parietal and subcortical brain regions during cognitive control processing (adjusted for age, sex, education, and fMRI task performance). Most associations were found for reactive cognitive control activation, indicating that poorer sleep health is linked to a “hyper-reactive” brain state. Analysis of time-on-task effects showed that, with longer time on task, poorer sleep health was predominantly associated with increased proactive cognitive control activation, indicating recruitment of additional neural resources over time. Finally, shorter objective sleep duration was associated with lower BOLD activation with time on task and poorer task performance. In conclusion, even in “normal sleepers,” relatively poorer sleep health is associated with altered cognitive control processing, possibly reflecting compensatory mechanisms and/or inefficient neural processing.
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