bluuebunny/crossref_metadata_2025 huggingface dataset:
Bioinformatics Analysis of ABCA4 Variants in Terms of Pathogenicity Prediction
Authors: Cevik Senem , Jones Jazzlyn S. , Alturkestani Albtool A. , Biswas Subhasis B. , Biswas‐Fiss Esther E.
Published: May 2022

ABCA4 is a retina‐specific member of the ATP‐binding cassette transporter protein family. It is responsible for the transport and clearance of retinal derivatives produced in the visual cycle in the photoreceptor cells. More than a thousand mutations in the ABCA4 gene are associated with a series of autosomal recessive inherited retinal diseases, including Stargardt disease, retinitis pigmentosa, and cone‐rod dystrophy, and also linked with susceptibility for age‐related macular degeneration. Determining disease‐causing variants is a crucial part of clinical management, yet, a limited number of the ABCA4 variants have been studied in vitro and relatively few of them have been functionally characterized. Bioinformatics approaches can be highly effective to interpret the consequences of the mutations more rapidly. In this study, we aim to analyze the pathogenicity of ABCA4 clinical and prospective variants utilizing two methods to infer mutation effects: prediction software and computational protein models. We hypothesize that these two approaches in combination will allow us to identify the consequences of the ABCA4 variants and gain insight into the overall structure and function of the protein. We found that the pathogenicity prediction software results align well with the structural analysis results in most instances. The clinical in silico prediction tools were found to predict pathogenicity more frequently than structural analyses, albeit with high sensitivity and low specificity. On the other hand, structure prediction tools are high specificity and thus, predict more accurately. Our results also indicate a correlation between disease severity and structural changes in protein models induced by genetic variations. Our findings suggest that computational analyses are promising tools to predict pathogenicity and can aid in the understanding of disease‐associated ABCA4 genetic variants. These computational approaches have additional applications in protein analysis and provide a strong framework for future in vitro studies.
Identifying Vesicular Localization of the Rho GTPase RhoJ/TCL Through Colocalization with Rab Family GTPases
Authors: Intriago Simone , Hamann Michael
Published: May 2022

TCL belongs to the Rho family of GTPases and contributes to tumor‐associated angiogenesis. Understanding its basic cell biology is essential for establishing its role in this process. Experiments in several labs have shown plasma membrane and vesicular localizations of TCL, but it is less clear as to what subtype of vesicle the GTPase associates with and how it may influence vesicle trafficking. To better understand this aspect of TCL cellular biology, a YFP‐tagged version of TCL was co‐expressed in HeLa cells with sixteen different mCherry‐tagged versions of Rab GTPases. Images were captured using an Olympus Fluoview confocal microscope and colocalization assessed both qualitatively and quantitatively using CellSens software. CL colocalized with Rab5 and 7 as previously published but we also show colocalization with Rab17 and 40. Since Rab5, 7, and 17 Rab GTPases have reported vesicular localizations and functions, we intend to assess whether TCL plays any roles in their established pathways.
Low‐Dose 6β‐Naltrexol Prevents Opioid Dependence Without Affecting Antinociception
Authors: Sadee Wolfgang , Oberdick John
Published: May 2022

We asked whether opioid dependence can be prevented during opioid pain therapy or maintenance therapy of opioid use disorder. We hypothesize that 6β‐naltrexol (6BN) binds to the basally activated μ opioid receptor (MOR) prevalent in dependence and gradually reverts it to its resting state, proposing a novel MOR model (1). Clinical utility of opioid analgesics is compromised by adverse effects and addiction liability, largely mediated by MOR, which displays spontaneous basal activity. It’s upregulation by opioid agonists can contribute to opioid dependence. Acting as inverse MOR antagonists in the dependent state, naltrexone and naloxone cause withdrawal at exceedingly low doses. We had identified 6β‐naltrexol (6BN) as a neutral MOR antagonist, which blocks antinociception and causes withdrawal only at much higher doses, even though its MOR affinity equals that of naltrexone. Weak antagonist potency of 6BN is due to both its neutral antagonism and peripheral selectivity because of slow entry into the brain. Nevertheless, low‐dose 6BN (LD‐6BN; <0.1 mg/kg) potently prevents the development of dependence in adult guinea pigs treated with methadone (6BN IC50=~0.01 mg/kg), presumably a central effect (2). To test whether LD‐6BN establishes meaningful 6BN levels in the brain, we measure blood and brain levels with a highly sensitive mass spectrometry assay. Following an s.c. 6BN dose of 0.02 mg/kg in guinea pigs, blood levels initially exceed brain levels tenfold, consistent with its peripheral selectivity, followed by rapid elimination from blood (t1/2 ~1h). In contrast, 6BN levels increased over 2h and persisted in brain for 8h at 1‐2 nM levels (t1/2 ~5h). Co‐administration of a saturating naloxone dose reduced 6BN brain levels by ~70% at 1‐3h, indicating saturable high affinity binding. The results show that LD‐6BN reaches central opioid receptor sites by slow penetration and long retention in the brain, enabling a possible gradually reversal of upregulated basal MOR activity. LD‐6BN appears to act as a dependence modulator rather than a typical opioid antagonist, accounting for its prevention of opioid dependence during agonist treatment, and possibly other aspects of opioid addiction.

1. W. Sadee, J. Oberdick, Z. Wang. Biased Opioid Antagonists as Modulators of Opioid Dependence: Opportunities to Improve Pain Therapy and Opioid Use Management. Molecules 25, 4163; doi:10.3390/molecules25184163 (2020)

2. A. Safa, A.R. Lau, S., Aten, K. Schilling, K.L. Bales, V. Miller, J. Fitzgerald, M. Chen, K. Hill, K. Dzwigalski, K. Obrietan, M.A. Phelps, W. Sadee, J. Oberdick. Pharmacological prevention of neonatal opioid withdrawal in a pregnant guinea pig model. Front. Pharmacol, DOI: 10.3389/fphar.2020.613328 (2021)
Heat Stress More Negatively Impacts Cardiac Muscle Mitochondria in Female Versus Male Pigs
Authors: Semanchik Pier L. , Wesolowski Lauren T. , Simons Jessica L. , Freestone Alyssa , Rudolph Tori E. , Roths Melissa , Rhoads Robert P. , Baumgard Lance H. , Selsby Joshua T. , White‐Springer Sarah H.
Published: May 2022

With continued trends toward more frequent and more severe heat events there is a greater risk of environment‐induced heat stress (HS). How persistently elevated core temperatures impacts body tissues remains largely unknown. Our preliminary evidence indicates HS may negatively impact cardiac tissue and that biological sex may play a role in HS‐mediated pathology. To further test the hypothesis that cardiac muscle mitochondria are more negatively impacted by HS in females than in males, samples were isolated from the left ventricle (LV) of the heart from 3‐month‐old castrated male and prepubertal female pigs that were exposed to thermoneutral (TN) conditions (n = 4 per sex) or HS conditions for 24 h at 37°C (HS; n = 6 per sex). Samples were analyzed for citrate synthase (CS) and cytochrome c oxidase (COX) activities, and for mitochondrial oxidative phosphorylation (P) and electron transfer (E) capacities via high resolution respirometry. Data were analyzed by mixed linear models in SAS v9.4 with treatment, sex, and treatment × sex as fixed effects. A traditional marker of mitochondrial volume density, CS activity, tended to be greater in TN males compared to HS males (P = 0.08) but was unaffected by HS in female pigs. Conversely, intrinsic (relative to CS activity) mitochondrial function, as measured by COX activity, was greater in TN females than HS females (P = 0.04) and within HS, males maintained greater intrinsic mitochondrial function than females (P = 0.02). Both integrative (relative to tissue wet weight) and intrinsic mitochondrial leak respiration were greater in HS than TN pigs (P = 0.03) but the contribution of leak to total E (flux control ratio; FCRLEAK) tended to be greater in males than females (P = 0.07). Conversely, both integrative and intrinsic maximal E (ECI+II) tended to be greater in female than male pigs (P = 0.08) indicating a greater degree of excess electron transfer capacity in females. The contribution of complex I‐supported P (PCI) to total E (FCRPCI) tended to be greater in TN compared to HS pigs regardless of sex (P = 0.09) and the contribution of maximal P to E (FCRPCI+II) was greater in TN females compared to HS females (P = 0.05). This resulted in the FCRPCI+IIbeing greater in males compared to females in the HS condition (P = 0.01), suggesting greater coupling of oxidative phosphorylation and electron transfer in cardiac mitochondria in males during 24 h of HS. These results suggest that HS may negatively impact cardiac muscle mitochondria in female pigs compared to males. Moreover, these data indicate that persistent HS has deleterious consequences for the myocardium and may represent an additional health concern caused by global climate trends. This project was supported by USDA NIFA Award #2020‐68014‐31954.
Biochemical Characterization of Starch Excess4 from Storage Crops
Authors: Cruz Juan Carlos , Raththagala Madushi
Published: May 2022

Starch is a water‐insoluble branched polymer of glucose. Its degradation requires the concerted action of glucan phosphatases and glucan dikinases. Reversible starch phosphorylation allows for the solubilization of the starch surface, allowing for amylase to degrade starch into maltose units. However, our understanding is limited on how these enzymes contribute to starch degradation in storage crops such as potato and cassava. In this study, we biochemically characterized cassava and potato SEX4 enzymes using enzymatic assays and differential scanning fluorometry. We determined the kinetics of SEX4 using both generic and physiologically relevant substrates. We also explored the utilization of these glucan phosphatase orthologs to enhance starch degradation in‐vitro. Our findings reveal that cassava and potato SEX4 show similar allosteric activation mechanisms but varying abilities to degrade starch under in‐vitro conditions.
Extending the Applications of Telomere‐Anchored PCR for Telomere Length Measurements
Authors: Witte Graeme , Kamau Natalie , Day Jessica , Yimenu Meklit
Published: May 2022

Chromosome ends contain repetitive, protein‐nucleotide sequences called telomeres that protect against DNA loss during replication. These noncoding sequences can vary in nucleotide identity as well as repeat sequence length. Our model system, Aspergillus nidulans, has a telomere sequence of 5’‐TTAGGG‐3’, which is the same as the human repeat sequence. Unlike in humans, who have a somewhat variable telomere length, those of A. nidulans are tightly regulated at roughly 110 bp. Using A. nidulans as a model, we previously designed an inexpensive and effective method termed telomere‐anchored PCR as an alternative for current telomere length methods that can be labor intensive and relatively expensive. However, the adaptability of this method and its efficiency at determining telomere length for organisms that might exhibit less stringent telomere length regulation remains uncharacterized. We initially examined the validity of this method in a similar species, Aspergillus oryzae. A. oryzae has a telomere repeat identity of 5’‐TTAGGGTCAACA‐3’ and has been shown to contain similar telomere lengths to A. nidulans of about 120 bp. Preliminary results suggest that telomere anchored PCR can function as an assay to determine telomere length in A. oryzae. This provides incentive to pursue optimization of the protocol for other Aspergillus species as well as additional organisms like Tetrahymena thermophila to further extend the applications of this quick and easy method.
Postnatal endocranial volume growth in Galago moholi
Authors: King Scot E. , McGovern‐Lind Brenna R. , Proffitt Kathryn A. , Vinyard Christopher J. , DeLeon Valerie B. , Smith Timothy D.
Published: May 2022

Our current knowledge of brain growth in non‐human primates is based on comparisons of brain weights in cadaveric newborns compared to adults. Previous work has revealed most strepsirrhine primates (e.g., lemurs and lorises) defer much of their brain growth to the postnatal timeframe. No studies have examined brain growth across postnatal ages, to determine when adult brain size is achieved relative to life history milestones such as weaning or eruption of adult dentition. Micro‐computed tomography via a Scano vivaCT 75 was utilized to scan six specimens, ranging from newborn (day 0) to adult. Amira software was then used to manually segment endocranial contours and generate endocranial volumes from each of the specimens. Preliminary data indicates that the neonatal Galago possesses roughly 44% of the endocranial volume of its adult counterpart. By the late infant stage (30 days), the Galago possesses roughly 70%, and by 60 days postnatal, 99% of the adult endocranial volume. This timeline precedes the weaning period seen at roughly 90 days. Other milestones are also reached at the same age. Galago is reported to be perfecting its signature leaps at 60 days, and in our sample, more than half of replacement teeth have erupted. Results do suggest that Galago, like other strepsirrhines, defers most brain growth to postnatal ages. But here, for the first time, we demonstrate a rapid increase in endocranial volume, well before complete feeding independence.
Role of the orphan receptors GPR21, GPR39, GPR82 and GPR6 in chronic inflammation in 3T3‐L1 adipose model
Authors: Gutiérrez Rojas Rocío A. , Aguayo‐Cerón Karla A. , De León‐Vargas Cruz , Villafaña Santiago , Romero‐Nava Rodrigo
Published: May 2022

Introduction Chronic or low‐level inflammation is a process where various immune cells are recruited from the periphery into adipose tissue. This event gives rise to localized inflammations, in addition to having a close interaction with cardiometabolic pathologies where the mediation of orphan receptors is observed. Objective To analyse the participation of the orphan receptors GPR21, GPR39, GPR82 and GPR6 in a chronic inflammatory process in 3T3‐L1 cells. Methods the cell culture of 3T3‐L1 was made in 6 wells plate (4 x105 cell per well) in DMEM/F12 medium. The 3T3‐L1 cell were stimulated with TNF‐α (10mM) during 30 minutes as an inflammatory model in the cells. The gene expression was measured by RT‐qPCR. Results our result showed that the inflammatory stimulus with TNF‐α in adipocytes decrease the expression of the orphan receptor GPR21 GPR26, GPR39, GPR82 and GPR6 that are related with low grade inflammation. Conclusion the orphan receptors expressed in adipocytes have a main role in the TNF‐α induces inflammation process, and they could be a therapeutic target to decrease the inflammation in some diseases related to low grade inflammation as diabetes, obesity and metabolic syndrome.
A High “Steaks” Molecular Story: Copper Interactions with Mad Cow Disease Prion Proteins
Authors: Muthukumar Vijay , Muthukumar Mehala , Kysilka Vojtech , Farahnakian Nura , Agha Sophie , Richardet Sonia
Published: May 2022

Transmissible spongiform encephalopathies (TSEs), better known as prion diseases, are a group of progressive neurodegenerative diseases that affect both animals and humans. The most well‐known example, bovine spongiform encephalopathy (BSE), better known as “mad cow disease,” is a progressive neurological disorder of cattle that is created as a result of a mutation in the cellular prion protein (PrPc) into a toxic isoform called PrP scrapie (PrPSc). This disease first gained public attention when a British outbreak affected about 180,000 cattle between 1986 and 2001, devastating numerous agricultural communities. The Independent School BioClub SMART Team used 3‐D modeling and printing technology to examine PrPc and PrPSc molecular structures, focusing specifically on the protein’s metal‐binding properties. Copper (II) ion (Cu2+), PrPc’s highest affinity metal ion, plays a significant role in the interdomain interaction between the globular C‐terminal domain, consisting of three □‐helices and one short □‐sheet, and the flexible N‐terminal domain. Cu2+ ion binds to the PrPc N‐terminal octarepeat domain (OR), which is considered fundamental due to its series of four (or more) tandem repeats. Each tandem repeat can bind one Cu2+ ion, which directly interacts with a specific highly conserved, negatively‐charged region of the globular domain defined by the exposed surface of helices 2 and 3. The N‐terminal domain of PrPc causes severe neurotoxicity unless the globular domain properly regulates it. In humans, this prion protein mutation leads to Creutzfeldt‐Jakob disease (CJD), which has the same neurodegenerative symptoms as BSE. A negatively‐charged region on the surface of helix 3 occupied by the Cu2+ ion also overlaps with the epitopes of many PrPc antibodies associated with prion diseases. A better understanding of these interactions could potentially lead to discovering a cure for neurodegenerative diseases caused by PrPc’s misfolded form, such as CJD and Alzheimer’s.
Coupling Metabolic Source Isotopic Pair Labeling and Genome Wide Association for Metabolite and Gene Annotation in Plants
Authors: Sipes Abigail , Luo Zhiwei , Chapple Clint
Published: May 2022

To deepen our understanding of plant gene function, it is important that we advance our knowledge of plant genomes and metabolic activity. With metabolite synthesis information in hand, we will have the capability to unlock higher plant productivity, develop new strategies to protect plants from stressors, and develop new plant‐based products. This project applies isotopic labeling to characterize amino acid‐derived metabolites in Arabidopsis and then applies Genome‐Wide Association (GWA) to identify the genes responsible for their synthesis. A computational pipeline was utilized to generate metabolic features that are derived from the labeled amino acids and then we applied criterions to determine mass features of interest. This project aims to classify metabolites based on the precursor‐of‐origin and to provide the function of annotated genes that are associated with plant metabolism. Using this method, the methionine‐derived metabolites glucoerucin, propylcysteine sulfoxide, glucoiberin, L‐methionine sulfoxide, and dihomomethionine were identified. It is likely that mass features in our computational pipeline were identified but they have yet to be identified as metabolites in the literature. This information can be referenced for future research in metabolite identification. In combination with GWA, this method can also help to identify metabolites and candidate genes associated with their synthesis. This method allows for users to mass identify and classify metabolites based on the precursor‐of‐origin.
Drug repurposing: A novel therapeutic approach for pancreatic cancer
Authors: Gaikwad Shreyas , Srivastava Sanjay K.
Published: May 2022

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with a survival rate of 10%. It is projected to be the second leading cause of cancer related deaths in USA by 2030. The therapeutic development against PDAC has been slow and chemotherapeutic resistance for available treatment options is a significant problem. Over the past few years, drug repurposing has shown promise as a fast, economic and reliable strategy to develop novel treatment options for most of the diseases. The repurposing of Remdesivir for COVID‐19 is a recent example. Based on literature review, we screened multiple drugs for their anti‐cancer efficacy and discovered potent anti‐cancer activity of an anti‐parasitic drug, MBO. We identified the anti‐cancer effects of MBO in human PDAC cell lines AsPC‐1, MiaPaCa‐2, BXPC3, Panc‐1 and SUIT‐2. We also confirmed the effect of MBO to suppress colony formation in PDAC cell lines AsPC‐1, MiaPaCa‐2 and BXPC3. MBO induced apoptotic cell death in PDAC cell lines which was confirmed by Annexin V/APC analysis using flow cytometry. Importantly, through western blot analysis we identified that MBO inhibits the DARPP‐32/β‐catenin axis, an unexplored cellular signaling axis in PDAC. This identification is crucial since DARPP‐32 is a novel protein which was recently identified to play a role in metastasis of PDAC. Pre‐clinical efficacy of MBO was evaluated in an in vivotumor model by subcutaneously injecting human PDAC cell line MiaPaCa‐2 in the left flank of the mice. MBO significantly suppressed tumor growth by 80% at an oral dose of 5 mg/kg. To summarize, our results show MBO inhibits the growth of PDAC by inhibiting the novel DARPP‐32/ β‐catenin axis.
Estimates of Resolution, Sensitivity, and Parallax Are Insufficient Parameters to Model the Visual Contributions to Animal Locomotor Performance
Authors: Heesy Christopher P.
Published: May 2022

Many animals rely on visual information to navigate natural environments. Comparative studies often cite visual resolution (acuity) and depth perception, either individually or in combination, as key traits required by running, gliding, flying and arboreal leaping animals to navigate environments without colliding into obstructions or misjudging properties of substrates. However, broad comparative analyses of the visual components to locomotor performance rarely include the limits of the resolution of distance or speed. Here, I analyze the relationship between visual resolution, sensitivity, and visual field geometry and locomotor performance. I model the limitations on depth, distance, size and orientation information available to animals using comparative visual and morphometric data from invertebrates and vertebrates. I then compare modeled estimates with data on mean and maximum speed as well as arboreal leaping and gliding distances. Morphometric results do not support the suggestion that visual parallax (a measure of depth information) covaries with locomotor type. Additionally, comparisons of visual resolution estimates at distance and velocities known for taxa within the dataset suggest that many animals cross discontinuous substrates and at speeds beyond the limits suggested by simple comparative measures of visual capabilities.
Thermal Stress and Antioxidant Activity in Sea Anemones, Exaiptasia pallida
Authors: Rideb Jernie Rae , Varghese Anabel , Nguyen Thien , Pham Kim , Nguyen Isabelle , Herrera Nadia , Bagnall Ruth Ann , Rosell Rosemarie
Published: May 2022

When exposed to stress, coral reefs undergo bleaching, a process in which the host‐symbiont relationship is disrupted. Stressors can be environmental including ocean acidification, exposure to ultraviolet radiation, or rising ocean temperatures due to global warming. The sea anemone, Exaiptasia pallida, serves as a model organism of coral reef biology since both species share symbiotic relationships with their algal symbionts and can undergo bleaching resulting in the expulsion of algal symbionts. This is the ultimate phenotypic result of high levels of stress experienced by the coral reef. Stress factors can lead to an increase in free radicals, like reactive oxygen species (ROS), that will adversely alter lipids, proteins, and DNA and trigger bleaching events. Although oxygen free radicals are natural by‐products of metabolic processes in most organisms, they are closely regulated through endogenous systems, such as antioxidants like superoxide dismutase (SOD). We hypothesized that as temperatures increase, the levels of SOD activity in the sea anemone will increase over time. We used commercially available E. pallida to establish a ‘stock’ aquaria to rear anemones under optimal conditions for at least two weeks before use. The stock aquaria were maintained at 28‐30% salinity at 22℃ during a 12‐hour light/dark period, at a pH of approximately 8.4, with low levels nitrate, nitrite, and ammonia (checked weekly). E. pallida were moved from the stock tank and placed into one of three identical tanks, maintained at increasing temperatures of 22℃ (control), 24℃, and 29℃. We sampled 5 anemones from each tank at two‐week intervals for 8 weeks. Seawater was removed by aspiration, anemones were weighed, flash‐frozen in liquid nitrogen, and stored at ‐80℃. We extracted proteins from each sample by homogenization on ice. For each sample, total protein concentrations were established with a Bradford assay and SOD concentration in units of activity was established with a commercially available SOD assay. By observation, the anemones reared at in the higher range of thermal stress appeared smaller and individuals tended to die faster during the trial. E. pallida reared under increased temperatures of 24℃ and 29℃ showed an increase in SOD activity from week 6 to week 8 compared to the control tank at 22℃. These data are based on two replicates and further trials are currently in progress. Our findings describe the outcome of elevated temperature on levels of metabolism and increased levels of superoxide dismutase activity as a byproduct of stress. In addition, disruption of a host‐symbiont relationship was suggested by the decrease in size and death of anemones at higher temperatures. Additional evidence is necessary to support our hypothesis and future experiments will focus on increasing the rearing time, increased temperatures, and other antioxidant defenses like xanthine oxidase or cyclooxygenases
The role of ABCC4 in pigment granule migration in RPE of mice
Authors: Wiebe Diana E.
Published: May 2022

ABCC4 is an ATP‐binding cassette protein that exports many substrates, including cyclic adenosine monophosphate (cAMP). In mammals, cyclic AMP accumulates in retinal photoreceptors in dark conditions. We conjecture that cyclic AMP is exported from the photoreceptors into the sub‐retinal space, where it becomes available for uptake by the retinal pigment epithelium (RPE), activating the process of pigment granule aggregation. We hypothesize that ABCC4 in photoreceptors mediates cAMP‐export and therefore is essential to the process of pigment granule migration in the RPE of mice. To investigate the involvement of ABCC4 in pigment granule movement, pigment granule density was measured along the basal part of the RPE for both wildtype and Abcc4 knockout mice that were light‐ or dark‐adapted (N = 3 for each treatment). Dark‐adapted wildtype mice showed significantly higher pigment granule density compared to light‐adapted wildtype mice, and no significant difference was seen between light‐adapted and dark‐adapted Abcc4knockout mice. A polyclonal antibody to ABCC4 used on zebrafish retinal sections showed the presence of ABCC4 in the outer retina by immunohistochemistry. These results are consistent with the hypothesis that ABCC4 plays a role in the regulating pigment granule position in RPE of mice.
Differential Expression of Adipokines in Mechanically Stretched‐ Endothelial cells
Authors: Al Ashmar Sarah , Kamareddine Layla , Zeidan Asad
Published: May 2022

Introduction

Hypertension is considered as the major risk factor for cardiovascular diseases, which are the leading cause of morbidity and mortality worldwide. This disease can develop mainly due to the mechanical forces exerted by the blood on the vessels wall. The endothelium, lining the blood vessel, responds to these hemodynamic mechanical forces such as mechanical stretch leading to endothelial dysfunction. Leptin and adiponectin (APN) are two adipokines that are known to be associated with the pathogenesis of hypertension. However, how the level of these hormones is elevated in response to mechanical stretch in endothelial cells is yet to be elucidated.

Aim

In the present study, we investigated the expression of leptin and adiponectin in endothelial cells exposed to mechanical stretch.

Methods

Immortalized human umbilical vein endothelial cells (EA. hy926) were subjected to mechanical stretch (15%, 60 cycle/min and 1Hz) using STREX cell stretching system (STREX Inc., California, USA) for 6, 16 and 24 h. Cultured cells not subjected to stretch (static condition) where used as controls. The mRNA expression of leptin and its receptor (OB‐Rb) as well as APN and adiponectin receptor 2 (APN‐R2) were assessed at different time points using real‐time PCR.

Results

Mechanical stretch induced changes in cell morphology in which the cells were elongated and aligned perpendicular to the stretch axis. Stretching of endothelial cells significantly upregulated the expression of leptin after 16 h (0.9515 ± 0.4238‐fold, n=6, p<0.05) and after 24 h (1.577 ± 0.4503‐fold, n=6, p<0.05) of stretching but without affecting the expression of its receptor (OB‐Rb). The mRNA expression of APN also increased significantly in response to 6 h stretching (0.5457 ± 0.1890‐fold, n=6, p<0.05), 16 h stretching (0.9487 ± 0.4058‐fold, n=6, p<0.05) and 24 h stretching (2.664 ± 0.3447, n=6, p<0.0001) compared to unstretched cells, however no change in the expression of APN‐R2 was observed.

Conclusion

Our findings suggesting that the exposure of endothelial cells to mechanical stretch can result in changes in the expression of adipokines, leptin and adiponectin, will result in better understanding of how vascular biology is affected by mechanical forces and how these molecules can modulate endothelial function in cardiovascular diseases.
Chloride Intracellular Channel Protein 1 (CLIC1) Inhibitor (IAA94) Decreases Contractile Force in Rat Uterine Arteries
Authors: Wilczynski Stephanie , Arishe Olufunke , Priviero Fernanda , Webb R. C.
Published: May 2022

Objective

The objective of this study was to determine the effects of the Chloride Intracellular Channel Protein 1 (CLIC1) inhibitor, IAA94, on uterine arteries in rats.

Hypothesis

This study tested the hypothesis that the inhibition of CLIC1 with IAA94 decreases contractility of the uterine artery.

Methods

Uterine arteries were harvested from 12‐week‐old female Wistar Rats. The arterial rings were mounted in a wire myograph and kept at 37ºC in Krebs solution, constantly aerated with a 95% O2+ 5% CO2 gas mix. Concentration‐response curves to Phenylephrine (PE, ‐9M to ‐4.5M). After washout, the arterial rings were incubated with the CLIC1 inhibitor (IAA94, 50 µM) for 30 minutes and then, concentration‐responses curves to PE were repeated. The curves were analyzed using nonlinear regression analysis and pEC50 and Emax were calculated with an N=8 for both groups. Data was analyzed by GraphPad Prism 9.2.0., and is presented as Mean ± SEM (n=8).

Summary of Results

In the Wistar uterine arterial rings, the potency of PE was decreased in the presence of the CLIC1 inhibitor IAA94 (pEC50: 5.64 ± 0.28 vs. 6.59 ± 0.30 for IAA94 vs control, respectively; p <0.0001). Similarly, Emax to PE was decreased after incubation with IAA94 (105 ± 2% vs 128 ± 5%, for IAA94 vs control, respectively; p <0.001). These data show that the inhibition of CLIC1 plays a role in the contraction induced by PE. Further experiments are necessary to understand the mechanisms underlying this effect.

Conclusion

The addition of the CLIC1 inhibitor, IAA94, elicits a decreased contractile response to PE. CLIC1 has been identified to be dysregulated in certain cancer types and aging. There are numerous overlaps between cell senescence/cancer morphology and the pathophysiology of preeclampsia. These preliminary experiments shed light on the uterine artery’s reactivity to a CLIC1 inhibitor and would be an interesting topic to pursue in pregnant rats in both SHR and Wistar strains. With hypertensive patients, we see an increase in peripheral contractility and a decrease in responsiveness to vasodilators. CLIC1 could be a possible target in vasoconstrictive pathways, especially those that occur during pregnancy and in preeclamptic patients.
Population Pharmacokinetics of Intranasal Dexmedetomidine in Infants and Young Children
Authors: Li Bi L. , Guan Yan P. , Yuen Vivian M. , Wei Wei , Huang Min , Zhang Ma Z. , Li Ai W. , Standing Joseph F. , Zhong Guo P. , Song Xing R.
Published: May 2022

Background

Intranasal dexmedetomidine provides noninvasive, effective procedural sedation for pediatric patients, and has been widely used in clinical practice. However, the dosage applied has varied fourfold in pediatric clinical studies. To validate an appropriate dosing regimen, this study investigated the pharmacokinetics of intranasal dexmedetomidine in Chinese children under 3 yr old.

Methods

Intranasal dexmedetomidine 2 µg · kg−1 was administered to children with simple vascular malformations undergoing interventional radiological procedures. A population pharmacokinetic analysis with data from an optimized sparse-sampling design was performed using nonlinear mixed-effects modeling. Clearance was modeled using allometric scaling and a sigmoid postmenstrual age maturation model. Monte Carlo simulations were performed to assess the different dosing regimens.

Results

A total of 586 samples from 137 children aged 3 to 36 months were included in the trial. The data were adequately described by a two-compartment model with first-order elimination. Body weight with allometric scaling and maturation function were significant covariates of dexmedetomidine clearance. The pharmacokinetic parameters for the median subjects (weight 10 kg and postmenstrual age 101 weeks) in the authors’ study were apparent central volume of distribution 7.55 l, apparent clearance of central compartment 9.92 l · h−1, apparent peripheral volume of distribution 7.80 l, and apparent intercompartmental clearance 61.7 l · h−1. The simulation indicated that at the dose of 2 µg · kg−1, 95% of simulated individuals could achieve a target therapeutic concentration of 0.3 ng · ml−1 within 20 min, and the average peak concentration of 0.563 ng · ml−1 could be attained at 61 min.

Conclusions

The pharmacokinetic characteristics of intranasal dexmedetomidine were evaluated in Chinese pediatric patients aged between 3 and 36 months. An evidence-based dosing regimen at 2 µg · kg−1 could achieve a preset therapeutic threshold of mild to moderate sedation that lasted for up to 2 h.

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Specificity of cortical area and thickness as biomarkers for comorbid internalizing and externalizing mental disorders in pre-adolescence
Authors: Kuang Nanyu , Liu Zhaowen , Yu Gechang , Zhang Kai , Wu Xinran , Becker Ben , Fan Huaxin , Zhao Jiajia , Kang Jujiao , Dong Guiying , Zhao Xingming , Feng Jianfeng , Sahakian Barbara J. , Robbins Trevor W. , Schumann Gunter , Palaniyappan Lena , Zhang Jie
Published: May 2022

Background

Comorbidity is the rule rather than the exception for childhood and adolescent onset mental disorders, but we cannot predict its occurrence and do not know the neural mechanisms underlying comorbidity. We investigate if the effects of comorbid internalizing and externalizing disorders on anatomical changes represent a simple aggregate of the effects on each disorder, and if comorbidity-related cortical surface changes relate to a distinct genetic underpinning.

Methods

We studied the cortical surface area (SA) and thickness (CT) of 11,878 preadolescents (9-10 years) from the Adolescent Brain and Cognitive Development Study. Linear mixed models were implemented in comparative and association analyses among internalizing (Dysthymia, Major Depressive Disorder, Disruptive Mood Dysregulation Disorder, Agoraphobia, Panic Disorder, Specific Phobia, Separation Anxiety Disorder, Social Anxiety Disorder, Generalized Anxiety Disorder, Post-Traumatic Stress Disorder), externalizing diagnostic groups (Attention-Deficit/Hyperactivity Disorder, Oppositional Defiant Disorder, Conduct disorder) a group with comorbidity of the two and a healthy control group. Genome-wide association analysis and cell type specificity analysis were performed on 4,716 unrelated European participants from this cohort.

Results

Reduced cortical surface area but increased thickness occurs across patient groups when compared to controls. Children with comorbid internalizing and externalizing disorders had more pronounced areal reduction than those without comorbidity, indicating an additive burden. In contrast, cortical thickness had a non-linear effect with comorbidity: the comorbid group had no significant CT changes, while those patient groups without comorbidity had significant thickness increases. Distinct biological pathways were implicated for regional SA and CT changes. Specifically, CT changes were associated with immune-related processes implicating microglia, while SA-related changes related mainly to excitatory neurons.

Conclusions

The emergence of comorbidity across distinct clusters of psychopathology is unlikely to be a simple additive neurobiological effect. Distinct risk-adaptation processes, with unique genetic and cell-specific factors may underlie SA and CT changes. Children with highest risk but lowest resilience, both captured in their developmental morphometry, develop a comorbid illness pattern.
An intermediate step in bridging the gap between evidence and practice: developing and applying a methodology for “general good practices”
Authors: Safadi Heléna , Lám Judit , Baranyi Ivett , Belicza Éva
Published: May 2022

The gap between evidence and clinical practice has been in the focus of researches for decades. Although successful implementation means the new knowledge must work in particular environments, it doesn’t mean that the entire process should exclusively be executed by the individual institutes. This is the point where we assumed that an intermediate step, the “general good practice”, could help to ensure that translation is done in a more professional way.

The development of the general good practice methodology was based on our infinitE model, which organized the factors of successful translation into an evidence-editing-embedding-effect on practice framework, using tools from the disciplines of Evidence-Based Medicine, Quality Improvement and Change Management.

The methodology organised the editing and embedding part of the development into a process involving three full-day sessions carried out with different health professionals, experts and moderators. After pilot testing, it was finalized and applied to other topics as well.

The methodology presented in detail in this paper, centred on flow chart, process analysis, failure mode identification and Kotter’s 8-step model. Beside the pilot topic of the institutional process of resuscitation, the methodology has also proved applicable to more than ten other topics, meaning that at least all the core elements of the proposed bundle of general good practice have been produced in the development process.

Compared to the guidelines, general good practices demonstrate the evidence in operation, helping to develop workflows, responsibilities, documentation, trainings, etc. and can also be a starting point for the digitalisation of care processes.

The next step is to examine how healthcare institutions can build on these in their own editing and embedding activities, and what the results will be. Further studies could explore the applicability of the development methodology in different healthcare systems or at different levels of maturity in terms of quality.
Evidence for Aerosol Transfer of SARS-CoV2-specific Humoral Immunity
Authors: Kedl Ross M. , Hsieh Elena , Morrison Thomas E. , Samayoa-Reyes Gabriela , Flaherty Siobhan , Jackson Conner L. , Rochford Rosemary
Published: May 2022

Despite the obvious knowledge that infectious particles can be shared through respiration, whether other constituents of the nasal/oral fluids can be passed between hosts has surprisingly never even been postulated, let alone investigated. The circumstances of the present pandemic facilitated a unique opportunity to fully examine this provocative idea. The data we show provides evidence for a new mechanism by which herd immunity may be manifested, the aerosol transfer of antibodies between immune and non-immune hosts.
Association between Intraoperative End-Tidal Carbon Dioxide and Postoperative Organ Dysfunction in Major Abdominal Surgery: A Retrospective Cohort Study
Authors: Dong Li , Takeda Chikashi , Kamitani Tsukasa , Hamada Miho , Hirotsu Akiko , Yamamoto Yosuke , Mizota Toshiyuki
Published: May 2022

Background

Data on the effects of intraoperative end-tidal carbon dioxide (EtCO2) levels on postoperative organ dysfunction are limited. Thus, this study was designed to investigate the relationship between the intraoperative EtCO2level and postoperative organ dysfunction in patients who underwent major abdominal surgery under general anesthesia.

Methods

We conducted a retrospective cohort study involving patients who underwent major abdominal surgery under general anesthesia at Kyoto University Hospital. We classified those with a mean EtCO2of less than 35 mmHg as low EtCO2. The time effect was determined as the minutes when the EtCO2value was below 35 mmHg, whereas the cumulative effect was evaluated by measuring the area below the 35-mmHg threshold. The outcome was postoperative organ dysfunction, defined as a composite of at least one organ dysfunction among acute renal injury, circulatory dysfunction, respiratory dysfunction, coagulation dysfunction, and liver dysfunction within 7 days after surgery.

Results

Of the 4,171 patients, 1,195 (28%) had low EtCO2, and 1,428 (34%) had postoperative organ dysfunction. An association was found between low EtCO2and increased postoperative organ dysfunction (adjusted risk ratio, 1.11; 95% confidence interval [CI], 1.03–1.20;p= 0.006). Additionally, long-term exposure to EtCO2values of less than 35 mmHg (≥224 min) was associated with postoperative organ dysfunction (adjusted risk ratio, 1.18; 95% CI, 1.06–1.32;p= 0.003) and low EtCO2severity (area under the threshold) (adjusted risk ratio, 1.13; 95% CI, 1.02–1.26;p= 0.018).

Conclusions

Intraoperative low EtCO2of below 35 mmHg was associated with increased postoperative organ dysfunction.
Genetic Risk Factors for Postoperative Atrial Fibrillation – a Nationwide Genome-Wide Association Study (GWAS)
Authors: Christensen Mathias A , Bonde Alexander , Sillesen Martin
Published: May 2022

Background

Atrial fibrillation (AF) is a major cause of morbidity with a high prevalence among the elderly and has an established genetic disposition. Surgery is a well-known risk factor for AF; however, it is currently not recognized how much common genetic variants influence the postoperative risk. The purpose of this study was to identify Single Nucleotide Polymorphisms associated with postoperative AF.

Methods

The UK Biobank was utilized to conduct a Genome-Wide Association Study (GWAS) to identify variants associated with AF after surgery. An initial discovery GWAS was performed in patients that had undergone surgery with subsequent replication in a unique non-surgical cohort. In the surgical cohort, cases were defined as newly diagnosed AF within 30 days after surgery. The threshold for significance was set at 5 × 10−8.

Results

After quality control, 144,196 surgical patients with 254,068 SNPs were left for analysis. Two variants (rs17042171 (p = 4.86 × 10−15) and rs17042081 (p = 7.12 × 10−15)) near the PITX2-gene reached statistical significance. These variants were replicated in the non-surgical cohort (1.39 × 10−101 and 1.27 × 10−93, respectively). Several other loci were significantly associated with AF in the non-surgical cohort.

Conclusion

In this GWAS-analysis of a large national biobank, we identified 2 variants that were significantly associated with postoperative AF. These variants were subsequently replicated in a unique non-surgical cohort. These findings bring new insight in the genetics of postoperative AF and may help identify at-risk patients and guide management.
Omicron sub-lineages BA.4/BA.5 escape BA.1 infection elicited neutralizing immunity
Authors: Khan Khadija , Karim Farina , Ganga Yashica , Bernstein Mallory , Jule Zesuliwe , Reedoy Kajal , Cele Sandile , Lustig Gila , Amoako Daniel , Wolter Nicole , Samsunder Natasha , Sivro Aida , San James Emmanuel , Giandhari Jennifer , Tegally Houriiyah , Pillay Sureshnee , Naidoo Yeshnee , Mazibuko Matilda , Miya Yoliswa , Ngcobo Nokuthula , Manickchund Nithendra , Magula Nombulelo , Karim Quarraisha Abdool , von Gottberg Anne , Abdool Karim Salim S. , Hanekom Willem , Gosnell Bernadett I. ,   COMMIT-KZN Team, Lessells Richard J. , de Oliveira Tulio , Moosa Mahomed-Yunus S. , Sigal Alex
Published: May 2022

The SARS-CoV-2 Omicron (B.1.1.529) variant first emerged as the BA.1 sub-lineage, with extensive escape from neutralizing immunity elicited by previous infection with other variants, vaccines, or combinations of both1,2. Two new sub-lineages, BA.4 and BA.5, are now emerging in South Africa with changes relative to BA.1, including L452R and F486V mutations in the spike receptor binding domain. We isolated live BA.4 and BA.5 viruses and tested them against neutralizing immunity elicited to BA.1 infection in participants who were Omicron/BA.1 infected but unvaccinated (n=24) and participants vaccinated with Pfizer BNT162b2 or Johnson and Johnson Ad26.CoV.2S with breakthrough Omicron/BA.1 infection (n=15). In unvaccinated individuals, FRNT50, the inverse of the dilution for 50% neutralization, declined from 275 for BA.1 to 36 for BA.4 and 37 for BA.5, a 7.6 and 7.5-fold drop, respectively. In vaccinated BA.1 breakthroughs, FRNT50 declined from 507 for BA.1 to 158 for BA.4 (3.2-fold) and 198 for BA.5 (2.6-fold). Absolute BA.4 and BA.5 neutralization levels were about 5-fold higher in this group versus unvaccinated BA.1 infected participants. The observed escape of BA.4 and BA.5 from BA.1 elicited immunity is more moderate than of BA.1 against previous immunity1,3. However, the low absolute neutralization levels for BA.4 and BA.5, particularly in the unvaccinated group, are unlikely to protect well against symptomatic infection4.This may indicate that, based on neutralization escape, BA.4 and BA.5 have potential to result in a new infection wave.