bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Various Body Positions on Arterial Stiffness as Assessed by Pulse Wave Velocity
Authors: Alhalimi Taha A. , Wang Tianyu , Meyer Michelle , Tanaka Hirofumi
Published: May 2022

Background

Standard measurements of arterial stiffness via pulse wave velocity (PWV) are conducted with participants in the supine position. When participants cannot tolerate supine position for prolonged procedure time (e.g., low back pain), accommodations may be made to tilt the bed up or bend the knees (i.e., Fowler’s positions). Moreover, a new testing device (Vicorder) that uses neck oscillometric cuff requires upper body tilt to avoid jugular vein interference on the recorded carotid pulse. Accordingly, this study aimed to investigate the effect of varying body positions on arterial stiffness measured via PWV.

METHODS

A total of 70 adults (43 women) varying widely in age (19‐66 years old), race/ethnicity (41% non‐white), and medical conditions were studied. Both carotid‐femoral PWV (cfPWV) and brachial‐ankle PWV (baPWV) were measured using two different testing devices (Omron vp1000plus and Vicorder) with participants in the reference supine (0º) position, 10º, 20º, 30º, and 40º upper body tilted‐up positions with and without knee flexion. The presence of jugular vein interference was documented visually on the oscillometric arterial waveforms at each body angle.

RESULTS

Both cfPWV and baPWV measured at 10º upper body tilt‐up position were not significantly different from those assessed at the reference supine (0º) position. Upper body angle of 20º or greater produced PWVs that were significantly and gradually elevated (p<0.01). The magnitude of elevations in cfPWV were 7% (95% CI [6‐11%]) at 20º and 15% (95% CI [11‐18%]) at 40º while the elevations in baPWV were 8% (95% CI [6‐10%]) at 10º and 33% (95% CI [30‐36%]) at 40º compared with the supine (0º) position. Knee flexion did not alter cfPWV compared with straight knees whereas knee flexion decreased baPWV at the same upper body angle (p<0.05). Jugular vein interference in the Vicorder device appeared on 78% of participants in the supine (0º) position and gradually decreased as the upper body angle increased, resulting in 7% of the participants at 30º angle. The appearance of Jugular vein contamination was not affected by knee flexion.

CONCLUSION

Arterial stiffness as assessed by cfPWV and baPWV increased gradually and significantly by the use of semi‐Fowler position of ≥20º whereas bending knees at each angle decreased baPWV, but did not appear to influence cfPWV. Our present findings highlight the difficulty in comparing two different devices that are supposed to reflect the same arterial property.
HIF1a and angiogenesis are critical for the regenerative effects of exercise
Authors: Ward Patricia , Wariyar Supriya , Tian Tina , Pottorf Tana , Brown Alden
Published: May 2022

Neurons whose axons reside in the peripheral nervous system (PNS) mount a limited regenerative program after injury that can be further enhanced by activity‐dependent therapies, such as exercise. The mechanism by which neuronal activity enhances axon regeneration is incompletely understood and defining how injured neurons respond to activity‐dependent therapies may reveal new therapeutic targets to improve recovery following both CNS and PNS injuries. We hypothesized that exercise utilizes an oxygen‐sensitive transcription factor, HIF1a, to enhance axon regeneration following injury. We found that running exercise caused nuclear translocation of HIF1a in axotomized sensory and motoneurons leading to enhanced axon regeneration and improved functional recovery following nerve injury. Conditional genetic deletion of HIF1a blocked the effect of exercise and prevented functional recovery. We then identified a pharmacologic inhibitor of prolyl hydroxylases that stabilizes HIF1a. Prolyl hydroxylase inhibition lead to increased DRG neurite outgrowth in vitro and enhanced axon regeneration in vivo. Manipulation of HIF1a via activity‐dependent therapies or pharmacologically enhanced regeneration and improved functional recovery. The quality of the surgical nerve repair also plays a large role in the aggregate success of nerve regeneration. Fibrin glue repaired nerves exhibited greater vasculature within the tissue bridge compared to nerves that were intrinsically repaired. Fibrin glue repaired nerves also exhibited more robust axon regeneration after exercise compared to nerves that were not repaired with fibrin glue. When angiogenesis of the tissue bridge was prevented with a VEGF receptor inhibitor, exercise was unable to enhance regeneration despite the presence of fibrin glue. Thus, HIF1a expression initiates the angiogenic response within the repair site through VEGF, but neuronal HIF1a expression is also required to promote the effects of exercise.
Design of variants of human fibroblast growth factor 1 with enhanced stability and cell proliferation activity
Authors: Sonnaila Shivakumar
Published: May 2022

Human Fibroblast growth factor 1 (hFGF1) is a member of FGF1 subfamily which play significant biological roles, including cell proliferation, cell differentiation, and wound healing. Under physiological temperatures, hFGF1 has low thermodynamic stability and susceptible to the action of proteases. Circular dichroism, fluorescence spectroscopy, and other related studies reveal that reversal of charge on R136 by acidic amino acids (Glu) drastically increases the enzymatic resistance to thrombin, thermal stability, and cell proliferation activity of the growth factor. Interestingly, introduction of R136D mutation shows that the protein stability and cell proliferation activity is similar to the wild‐type protein. Microsecond molecular dynamics studies suggest that length of the side chain of acidic amino acid at position 136 is critical to confer stability to the protein. Detailed analysis of the results will be presented.
Investigating the Role of Base‐Triples in the HTLV‐1 pro‐pol Frameshift Site Pseudoknot
Authors: Maille Madison M. , Mouzakis Kathryn D.
Published: May 2022

The human T‐cell leukemia virus type 1 (HTLV‐1) RNA genome includes two programmed ‐1 ribosomal frameshift sites. Each site includes three RNA elements: a slippery sequence, a spacer, and a structure. We recently determined that the pro‐pol frameshift site contains a pseudoknot structure. Research on other viral frameshift site pseudoknots indicates that contacts between single‐stranded loop nucleotides and base‐pairs in the stems are often critical to pseudoknot function. Although the HTLV‐1 pseudoknot tertiary structure is not determined, base‐triples may form between its two loops and two stems. To test the hypothesis that these tertiary contacts were critical to its function, the frameshift efficiencies were measured for the wild‐type frameshift site and three mutants. Two mutants (A2295U and Loop 2 A to U) were designed to disrupt putative base‐triples forming between loop 2 and stem 1. A third mutant (U2272C) was designed to evaluate the impact of a stem 2 G•U to G‐C substitution. Preliminary data from quadruplicate measurements showed that the frameshift efficiency for all three mutants was moderately increased relative to the wild‐type frameshift site. Whether the changes in the A2295U and Loop 2 A to U mutant frameshift efficiencies were caused by changes to tertiary contacts is hard to determine without complementary methods that establish their presence. Although the increase in the U2272C mutant frameshift efficiency could relate to tertiary contacts, it is more easily explained by a change to the stem 2 thermodynamic stability. Future work will focus on leveraging other methods to evaluate these possibilities.
Fluorescent detection of RNA using a base excision reporter
Authors: Harcourt Emily M. , Jun Yong Woong , Wilson David L. , Ledgerwood Emily D. , Kool Eric T.
Published: May 2022

A fluorescent probe originally designed for the detection of abasic sites and monitoring of DNA repair has been successfully used in the detection of RNA. The strategy employs deoxyuridine in a DNA probe complementary to the target RNA; the RNA/DNA hybrid was found to be a substrate for uracil‐DNA glycosylase. After excision of uracil, rapid oxime formation between the hydroxylamine probe and the abasic site leads to a ~10‐fold increase in fluorescence in the presence of the target RNA. Additional signal can be gained by incorporating multiple deoxyuridine nucleotides through reverse transcription. Reverse transcription, base excision, and probe incorporation can be carried out concurrently in a single vessel.
Host Regulation of Ebola Virus Egress and Spread: Role of Cytoskeletal Filamin Proteins
Authors: Shepley‐McTaggart Ariel , Shtanko Olena , Harty Ron N.
Published: May 2022

Ebola virus (EBOV) causes severe hemorrhagic fever associated with high mortality rates in humans. EBOV and other filoviruses are emerging BSL‐4 pathogens for which the development of novel and effective therapeutics is urgently needed. Egress and spread of EBOV is mediated by the VP40 matrix protein (eVP40), whereby expression of eVP40 alone directs the production and egress of virus‐like particles (VLPs) that accurately mimics the budding process of live infectious virus. We have shown that eVP40 hijacks or recruits select host proteins to facilitate the budding process. On the other hand, we have also identified several host proteins that interact with eVP40 to negatively regulated eVP40‐mediated budding. Thus, a better understanding of the eVP40‐host interactome will provide important insights into the mechanisms of virus egress and spread, as well as inform about potential targets for the development of novel antiviral therapeutics. Here, we investigated the possible role for host filamin A and B proteins (actin crosslinking proteins that function in cell morphology and migration at the plasma membrane) in regulating both entry and egress of EBOV. Toward this end, we employed filamin A (FLNaKD) and filamin B knockdown cells (FLNbKD) to assess EBOV entry by using live EBOV, as well as recombinant viruses and/or pseudotypes expressing the EBOV surface glycoprotein (GP). We also used the KD cells to assess virus egress by using our well‐established eVP40 VLP budding assay. In sum, our results indicate that expression of host filamin proteins appears to be important for EBOV to efficiently complete different stages of its lifecycle.
Silencing of NILCO by Small Interfering RNA Effects MDR1 in Colon Cancer Cells
Authors: Erkasap Nilufer , Gultekin Aysel , Ozyurt Rumeysa , Ozkurt Mete
Published: May 2022

The aim of the study is to investigate the effect of silencing of NILCO by siRNA on the MDR1 gene, which plays a role in chemoresistance. Cells of the human colon cancer lines Caco‐2 and HT‐29 were cultured at 37˚C in DMEM supplemented with 5% FBS in a humid incubator with 5% CO2. Exponentially growing untreated Caco‐2 and HT‐29 cells were collected and plated (4 x 105/ well in 2 mL) 24 hours before transfection. Plated cells were treated with either double‐stranded siRNA targeting Notch1 mRNA, leptin mRNA, IL‐1 β mRNA, control siRNA, or Paclitaxel (PTX) alone, Notch1 siRNA+PTX, Leptin siRNA+PTX, IL‐1β siRNA+PTX. The siRNAs of Notch1, IL‐1β and Leptin, were applied to the cells at a final concentration of 30 nM, and the cells were transfected with siRNA for 48 hours. After transfection, 100 nM Paclitaxel chemotherapeutic agent for HT‐29 and 130 nM for Caco‐2 was applied to the cells. Cells were harvested for PCR analysis after treatment with PTX for 24 hours.

According to our findings, MDR1 gene expression was significantly increased in the paclitaxel group compared to the control group (p<0.05). Silencing of Notch, leptin and IL‐1β decreased MDR1 gene expression compared with the control group, but it was not statistically significant. (p>0.05). However, our results indicated that Notch1 siRNA+PTX, IL‐1β siRNA+PTX and Leptin siRNA+PTX downregulated MDR gene expression in the Caco‐2 cell line compared with PTX alone treated group (p<0.01). In addition, MDR1 gene expression levels were significantly decreased in the Leptin siRNA+PTX and IL‐1β siRNA+PTX groups compared with PTX alone group in the HT‐29 cell line, but the decrease in the Notch1 siRNA+PTX group was not statistically significant. (p<0.01, p<0.05, p>0.05). In conclusion, knockdown of NILCO genes is effective in regulating MDR1 expression, which is a hallmark in chemoresistance.

The present study was supported by Eskisehir Osmangazi University Scientific Research Projects (BAP) Coordination Unit (grant no. 202011D11).
RSK as a Therapeutic Target for ER+ Breast Cancer
Authors: Faltas Christina , Holz Marina K.
Published: May 2022

We focus on identification of kinase signaling pathways, inhibition of which could be used in combination with endocrine therapy for treatment of Estrogen Receptor (ER)‐positive breast cancer. The p90 Ribosomal S6 Kinase (RSK), an effector of the MAPK signaling pathway, plays a key role in cell growth and survival, through the regulation of many downstream targets, and may serve a role in promoting response to endocrine therapy. To further elucidate the role of RSK in crosstalk with estrogen signaling pathways, we first examined the expression of RSK in ER‐positive breast cancer subtype and correlation with phosphopeptide abundance using phosphoproteomics analysis. Our results suggest that RSK is highly expressed in ER‐positive breast cancer and also promotes the phosphorylation of many targets involved in cell growth and survival signaling pathways. Our ongoing investigation characterizes the role of new targets of RSK in ER‐positive breast cancer, with the long‐term goal to develop further targeted therapies that can increase sensitivity to endocrine therapy and prevent the development of therapeutic resistance.
ATP10A has a protective and sex‐specific role in lipid metabolism
Authors: Norris Adriana C. , Yazlovitskaya Eugenia , Zhu Lin , Rose Bailey , Yu Sophia , McLean John A. , Stafford John , Graham Todd R.
Published: May 2022

Genetic predisposition and environment play substantial roles in obesity, type 2 diabetes and cardiovascular disease (CVD). Genetic association studies have linked ATP10A, encoding a type IV P‐type ATPase (P4‐ATPase), to human metabolic disease. ATP10A is a lipid flippase that catalyzes the membrane translocation of phosphatidylcholine and glucosylceramide. These lipids and their respective metabolites have been independently implicated in metabolic dysfunction. To explore the role of this flippase in metabolism, we created a novel Atp10aknockout (KO) mouse model. Atp10a KO mice display a female‐specific weight gain during high‐fat diet feeding and this is attributable to increased adiposity. Female Atp10a KO mice also exhibit elevated plasma free fatty acids, cholesterol, and triglycerides, as well as a depletion in eicosanoid species compared to the wild type (WT) littermates. Additionally, female Atp10a KO mice exhibit elevated fasting blood glucose levels without compensatory elevation of insulin. We also found that the liver of female Atp10aKO mice displays larger lipid droplets, which was associated with increased diacylglycerol acyltransferase‐2 (DGAT2) expression and an attenuation of the insulin signaling pathway compared to the WT littermates. Thus far, our studies have shown that knocking out Atp10a in mice on a high fat diet results in sex‐specific perturbations to body composition, plasma lipid levels, glucose homeostasis, and liver metabolism. We have recently found that ATP10A is specifically expressed in the endothelial cells of multiple tissues. We are now exploring these metabolic phenotypes through the lens of endothelial cell dysfunction. These studies suggest mechanisms by which this flippase contributes to the development of CVD with obesity.
High‐Frequency 4D Ultrasound Evaluation of Temporal Changes in Endocardial Surface Strain after Myocardial Infarction
Authors: Nelson Benjamin , do Carmo Jussara M. , Hall John E. , da Silva Alexandre A. , Omoto Ana Carolina Mieko
Published: May 2022

Myocardial infarction (MI) is a leading cause of death and accurate assessment of cardiac function after MI is critical for understanding mechanisms of post‐MI remodeling, recovery and treatment. Most previous studies assessed cardiac function using echocardiographic images of only one section of the heart. Newly developed high‐frequency 4D ultrasound (4DUS) may provide more accurate evaluation of cardiac function, especially after MI when geometry of the heart is abnormal. We investigated left ventricle (LV) endocardial surface peak systolic strain (SPSS) using 4DUS images (VEVO‐3100) before (baseline) and 24‐hr, 72‐hr and 1‐week post‐MI in male Sprague‐Dawley rats (n=5) subjected to left descending coronary artery ligation. Full‐length LV short‐axis ECG‐gated cine loops were acquired with ~11 µm stepwise increments. Compared to baseline, ejection fraction was significantly reduced 24‐hr, 72‐hr and 1‐week post‐MI (65±1 vs. 35±1, 34±3 and 31±2%, respectively). We also observed that SPSS showed different contractility patterns in the base, mid and apical heart regions. Among 17 myocardial segments analyzed, only septal segments were not affected by MI, with the exception of base anterior septal segment which showed reduced SPSS 72‐hr post‐MI (‐4.3 ± 2%) compared to baseline (‐26.5 ± 3%), indicating that the base is more sensitive to MI injury than mid‐LV. Since cardiac global and regional metrics are usually estimated in the mid‐LV, conventional methods may underestimate cardiac function in MI models. Thus, 4DUS with 3D‐strain analysis appears to be a valuable and sensitive tool for improved detection of cardiac disease progression.
Liraglutide as a Prophylactic Treatment for Sepsis Induced Lung Inflammation and Edema
Authors: Baer Brandon , Putz Nathan D. , Gibson Dustin , Toki Shinji , Peebles Stokes , Cahill Katherine N. , Bastarache Julie A.
Published: May 2022

Background

The severe lung dysfunction that characterizes acute respiratory distress syndrome is associated with excessive inflammation and edema. It occurs after an initiating insult to the lung, the most common of which being sepsis. As such, our research group has been investigating a glucagon‐like peptide‐1 (GLP‐1) receptor agonist, liraglutide, that inactivates NF‐κB, a transcription factor involved in the inflammatory response associated with sepsis.

Hypothesis

prophylactic treatment with liraglutide reduces lung inflammation and edema associated with a septic insult.

Methods

We pretreated C57/Bl6J mice two times a day with liraglutide (0.1mg/kg) or placebo (PBS) seven days prior to a two‐hit model of acute lung injury (cecal slurry induced polymicrobial abdominal sepsis and exposure to hyperoxia). To induce sepsis, an intraperitoneal injection of either 5% dextrose (control) or cecal slurry (2.4mg/g) was administered. Mice were then placed in a hyperoxia chamber (95%). At 6‐hours post cecal slurry injection mice were euthanized, a bronchoalveolar lavage (BAL) was performed, and lung tissue was collected. BAL was analyzed to measure protein content, leukocyte influx, and cell differentials. Wet‐dry ratios of lung tissue were also calculated.

Results

Compared to PBS and liraglutide treated sham mice, cecal slurry+hyperoxia caused an increase in markers of lung inflammation and edema. Septic mice pretreated with liraglutide had significantly decreased lung inflammation as measured the total number of inflammatory cells (2.2 vs 8.75 x 104 cells/ml; p<0.01; Figure 1) and neutrophils (0.33 vs 16.15 x 103 cells/ml; p<0.01) compared to untreated septic mice. Similarly, these septic mice also had significantly decreased lung edema as measured by wet‐dry ratios (4.15 vs 5.49; p<0.01) and protein content (285.52 vs 889.54 pg/ml; p<0.01).

Discussion

These results suggest that GLP‐1 receptor agonism attenuates sepsis and hyperoxia‐induced increases in lung inflammation and edema. Further, this data provides a strong rationale for additional studies, in other pre‐clinical models, to evaluate the potential of this receptor as a therapeutic target.
Biomarkers Indicative of Late Stage Alzheimer’s Disease Found in the Brain and Retina
Authors: Sein Than , Abram David , Bondarenko Vladimir
Published: May 2022

Purpose

Alzheimer’s Disease (AD) is a common neurological disorder affecting millions

of individuals worldwide, and therefore identification of retinal biomarkers

for a noninvasive diagnosis of the disease is critical to confirm the presence of this brain disorder.

Methods

Cryosections of brains and retinas from cadavers were analyzed. The structures of the brain specifically focused on were the prefrontal cortex (PFC), hippocampus, temporal lobe, visual cortex. Each tissue section was immunostained with antibodies against total tau (TT), phospho‐tau 181 (PT181), phospho‐tau 205 (PT205), and beta‐amyloid (BA). Every stained section was then microscopically analyzed to compare and contrast each marker using optical density (OD) measurements.

Results

2 cadavers without a history of neurodegenerative disease (1 male, 1 female) and 4 cadavers affected by AD (2 males, 2 females) were used. Retina samples of AD cadavers expressed a statistical significance increase in OD of the TT marker when compared to normal cadavers (AD = 0.37 OD ± 0.179, Normal = 0.01 OD ± 0.0049). In regards to the brain structures, only the TT markers in PFC were found to have statistical significant increases in OD value (AD = 0.28 OD ± 0.0621, Normal = 0.04 OD ± 0.0423). TT, PT181, PT205, and BA also expressed slight increases in OD in several brain structures of the AD cadavers but were not found to be statistically significant.

Conclusion

There is a significant increase in the TT marker in the retina with similar findings in the PFC. This suggests that using TT as a marker in the PFC and retina has the highest potential to aid in diagnosing AD, with a possibility of studying the progression of AD through TT in different areas of the brain in future research.
Crystal Structures of an E1‐E2‐ubiquitin Thioester Mimetic Reveal Molecular Mechanisms of Transthioesterification
Authors: Olsen Shaun K.
Published: May 2022

E1 enzymes function as gatekeepers of ubiquitin (Ub) signaling by catalyzing activation and transfer of Ub to tens of cognate E2 conjugating enzymes in a process called E1‐E2 transthioesterification. The molecular mechanisms of transthioesterification and the overall architecture of the E1‐E2‐Ub complex during catalysis are unknown. Here, we determined the structure of a covalently trapped E1‐E2‐ubiquitin thioester mimetic. Two distinct architectures of the complex are observed, one in which the Ub thioester (Ub(t)) contacts E1 in an open conformation and another in which Ub(t) instead contacts E2 in a dramatically different closed conformation. Altogether our structural and biochemical data suggest that these two conformational states represent snapshots of the E1‐E2‐Ub complex pre‐ and post‐thioester transfer, and are consistent with a model in which catalysis is enhanced by a Ub(t)‐mediated ‘affinity switch’ that drives the reaction forward by promoting productive complex formation or substrate release depending on the conformational state.
Interspecific Variation in Oxygen‐Binding Properties of Scorpion Hemocyanin
Authors: Spacht Drew E. , Gefen Eran
Published: May 2022

Though they don’t display much structural variation in their respiratory systems, scorpions exhibit variable lifestyles that may necessitate different aerobic capacities. These lifestyles are largely conserved at the family level – typically, members of the family Buthidae do not burrow, unlike most members of Scorpionidae. Among digging scorpions, burrows can be dug overnight and may reach depths of up to 1m. Scorpions, like many other arachnids, utilize hemocyanin as a respiratory pigment in the hemolymph. We therefore hypothesized that the oxygen‐binding affinity of hemocyanin would vary between buthids and scorpionids. To test this hypothesis, we used a Blood Oxygen Binding System (Loligo Systems) to determine the partial pressure of oxygen required to reach 50% oxygen‐saturation of hemocyanin (P50) among three buthids (Leiurus hebraeus, Buthus Israelis, and Hottentotta judaicus) and two scorpionids (Scorpio fuscus and Scorpio palmatus). We predicted that scorpionids would have higher P50 values, as lower O2 affinity would enhance oxygen release at the muscles during intense bouts of exercise. Our preliminary data supports this hypothesis ‐ buthids had lower P50 values than scorpionids. Mean (±SD) P50 values of buthids (12.34±1.83 Torr for L. hebraeus (n=8), 18.86±2.89 Torr for B. Israelis(n=13), and 19.78±6.38 Torr for H. judaicus (n=8)) were significantly lower than that of S. fuscus (46.11±10.57 Torr; n=9). S. palmatus had a lower P50 (25.73±8.64 Torr) than all three buthids, though the differences were not significant – perhaps due to small sample size (n=4). Taken together, these data suggest hemocyanins in scorpions have evolved to address the physiological demands associated with burrowing behavior.
Levator Palpebrae Superioris: Development, Structure, Variation, and Clinical Implications
Authors: Garcia Javier , Cabrera Bryan , Alonso Dailen , Valdes Javier , Eahrhardt John , Gomez Ferdinand
Published: May 2022

The purpose of this review is to present a comprehensive synopsis of the current literature on the development and structure of the levator palpebrae superioris muscle (LPS) with an emphasis on known variations as well as clinical implications of said structures. Furthering an understanding of LPS variations and clinical presentations will afford a more informed approach for surgical reconstruction procedures as well as guide clinical considerations during presentations of lid lag, blepharoptosis, eyelid retractions, etc., that are prevalent with congenital ptosis, age‐related ptosis, and Grave’s disease. Embryologically, the LPS arises from the superior rectus around the 46th day of the prenatal period and remains bound and share a common epimysium that begins dividing by the fifth fetal month. Subsequent anterograde projection of the LPS allows for connections with the skin through the ciliary portion of the orbicularis oculi muscle. Anatomic variations of the LPS have been noted at higher incidences in fetal studies when compared to adult cadaveric dissections. Variations arising from muscular slips which split off the medial or lateral margins have been described unilaterally or bilaterally and can progress to acquire their own muscular identity and can be supplied by branches of the trochlear n.
Efficacy of Extracorporeal Shockwave Therapy on Knee Osteoarthritis Related Pain and Activities of Daily Living: A Systematic Literature Review
Authors: Baloy Rodiel Kirby L. , Campbell Eamon , Duong Allen
Published: May 2022

Purpose

Extracorporeal Shockwave Therapy (ESWT) is currently being marketed and advertised as a safe treatment alternative for various musculoskeletal conditions including osteoarthritis. There has been an increased interest in the use of ESWT as a noninvasive passive modality by physical therapists as an adjunct to holistic care. This literature review aims to look at the state of evidence among previous systematic reviews and randomized controlled trials examining the application of ESWT for pain and activities of daily living (ADL) outcomes for individuals with knee osteoarthritis (OA).

Methodology

Systematic literature searches for randomized controlled trials between 2010‐2021 were performed in the databases of PubMed, PEDro Database, Google Scholar, Cochrane Library, EBSCO between November 18 to December 8, 2021. A total of six randomized controlled trials (full text available, PEDro score > 6, and conducted in the past 11 years) with a total of 459 subjects met quality guidelines using the PEDro scale. There were 5 systematic reviews (full text available, inclusion criteria, pain and ADL outcome measures, and conducted in the past 11 years) with a total of 6922 subjects that met methodological guidelines.

Results

A total of 2682 articles were screened, and 6 studies with a total population of n = 459 were included in this review. With heterogeneity in frequency, dosage, and volume no meta‐analysis was conducted. There were statistically significant improvements reported in the use of ESWT in terms of pain and ADL outcomes associated with knee OA in 5 of the studies (n= 370). No clinically significant differences were found in the use of ESWT for knee OA related pain and ADL outcomes in 1 of the studies (n=89), and no studies found nil effects. The results suggest that in the management of symptoms related to knee OA, the use of ESWT has some effect on pain and activities of daily living outcomes.

Conclusions

A review of current randomized controlled trials and systematic reviews presented some evidence for the use of ESWT in knee OA. While the use of ESWT may improve pain and ADL outcomes, further studies towards dosing and prescription is suggested.
Molecular Mechanism of Vibrio cholerae biofilm adhesion
Authors: Weerasekera Ranjuna , Hinbest Alex , Nero Thomas , Huang Xin , Yan Jing , Olson Rich
Published: May 2022

Biofilms are communities of microorganisms that play a significant role as virulence factors in disease transmission. The ability to attach to surfaces is an important feature which facilitates both host colonization and survival in the environment. To attach to a wide array of biotic and abiotic surfaces, biofilm‐dwelling bacterial cells need to produce specific adhesion molecules. The causative agent of pandemic cholerae, Vibrio cholerae, forms biofilms dependent on Vibrio polysaccharide (VPS), the primary component of the biofilm matrix, which makes a significant contribution to the structural integrity of the biofilm. In addition to VPS, the biofilm matrix contains proteins and nucleic acids; together these components play an important role in maintaining the integrity of the biofilm. The three main proteins of the biofilm matrix are RbmA, RbmC and Bap1. In this study we focus on RbmC and Bap1, which are considered adhesion proteins with overlapping but distinct functions. Both proteins share sequence identity and core structural features: a β‐propeller domain, and a β‐prism domain. RbmC contains two functional β‐prism domains which bind with high affinity to the core of complex N‐glycans, while Bap1 has only one domain which appears to have lost the ability to bind glycans. Our study finds that the two adhesins differ in the adhesive properties of the β‐prism domains that interface with the external environment. The current study combines insights from prior crystallographic work with functional assays in V. cholerae biofilms to demonstrate the modular nature of Bap1 and RbmC and how V. cholerae utilizes these two biofilm‐specific adhesins to achieve robust adhesion to various types of surfaces. We also propose a model for how V. cholerae biofilms recognize host surfaces specifically during infection while retaining adhesion to abiotic surfaces. This emphasizes the critical need to develop new biofilm elimination strategies, both from abiotic surfaces and post‐infection as an alternative to antibiotics due to the development of antibiotic resistance.
Salivary Microbiota is Associated with Cannabis Use in Adolescents
Authors: Browning Brittney D. , Kirkland Anna , Liu Helen , Green ReJoyce , Ticer Taylor , Glover Janiece , Engevik Melinda , Squeglia Lindsay
Published: May 2022

Purpose

Cannabis is now the second most commonly used substance during adolescence, with 35.7% of 18‐year‐olds reporting use in the past year and 6.4% reporting daily use. Accumulating evidence suggests that cannabis use affects the microbiome, however, this is still underexplored. Given that adolescence is a vital period of neural and microbial development, it is essential to investigate if cannabis use is associated with differences in microbiota as perturbations to microbial systems during this period of development may influence brain development.

Methods

Saliva biospecimens were collected from adolescent (15‐19 years old) cannabis users (N=8) and control participants (N=9) in an ongoing clinical trial (K23 AA025399) at the Medical University of South Carolina. Bacterial quantification was performed by real‐time quantitative PCR (qPCR) using primers for representative oral phyla (Bacteroidetes, Firmicutes, Proteobacteria, and Actinobacteria) and related species (Staphylococcus, Clostridium coccoides, Clostridium leptum, Lactobacillus, Escherichia coli, Bacteroides, and Prevotella). Standard t‐test was used to compare the relative abundances between the cannabis using group and control group. Correlations between levels of oral phyla and related species with cannabis use days reported on the Timeline Follow back (TLFB) and Cannabis Use Disorder Identification Test (CUDIT) scores were completed.

Results

All saliva samples contained significant levels of bacterial gDNA (mean concentration: 96.9 ng/μl; ~10 ng/μl is sufficient). We observed significantly lower levels of Proteobacteria (p=0.031) and Bacteroides (p= 0.006) in the cannabis‐using group compared to the non‐cannabis‐using control group. Additionally, the number of cannabis use days reported on the TLFB and CUDIT scores were inversely correlated with Bacteroides levels (p= <0.001, p=0.011 respectively).

Conclusion

These preliminary data suggest that cannabis use during adolescence may be associated with changes in the oral microbiota, specifically in Proteobacteria and Bacteroides. The lower abundance of Bacteroides in the cannabis using group is further strengthened by the inverse correlations between cannabis use days and CUDIT scores. Interestingly, Bacteroidesactively expresses GABA‐producing pathways, a type of inhibitory neurotransmitter pathway that studies have shown is inhibited by THC. In addition, ratios of Bacteroides from stool microbiota analyses have also been reported to be decreased in cannabis users. Therefore, saliva microbiota collection may serve as a favorable alternative to classic stool collection. Inclusion of more participants in future studies will allow for more power to detect microbial differences within adolescents who use cannabis.
Optogenetic Control of Phosphatase and Kinase Function
Authors: Ryan Amy , Zhou Wenyuan , Shoger Karsen E. , Courtney Taylor M. , Gottschalk Rachel A. , Deiters Alexander
Published: May 2022

Signal transduction is an essential mechanism of cellular function. These pathways are responsible for eliciting a physiological response to external stimuli, resulting in biological processes such as cell cycle progression, proliferation, and cell fate determination. However, the complex networks of protein kinases and phosphatases that are responsible for signal regulation are difficult to study through biochemical and genetic methods. These traditional techniques fail to offer the acute spatial and temporal resolution that optical control provides. To that end, the objective of this research is to apply genetic code expansion to install light‐removable caging groups on critical residues for photo‐activation of phosphatase and kinase function. We hypothesized that protein activity can be restricted through the incorporation of a genetically encoded photocaged amino acid in place of 1) a conserved catalytic residue, 2) an active site‐adjacent residue, or 3) a protein docking site essential for enzyme/substrate interaction. The resulting precise temporal control, together with complete genetic specificity, will enable the dissection of intricate cell signaling mechanisms, including crosstalk regulation between signaling cascades. Here we describe the attempted photoregulation of SH2‐containing protein tyrosine phosphatase‐2 (SHP2) through three different sites of installation, using three unique unnatural amino acids. These approaches have been validated in conjunction with a fluorogenic phosphatase substrate and a live cell reporter. Additionally, we have demonstrated light activation of four unique isoforms of the mitogen‐activated protein kinase (MAPK), p38. We have utilized the isoform‐selective perturbation of kinase activity to reveal contradicting functions of p38 variants, resulting in either positive or negative crosstalk with the extracellular signal‐regulated kinase (ERK)/MAPK pathway by the γ/δ and α/β subsets, respectively. We conclude that genetic code expansion can be utilized to engineer photocontrol of enzymes via diverse methods, resulting in the precise examination of protein function within the context of complex cell signaling cascades, thereby delivering an additional understanding of kinase and phosphatase function.
Oxygen Tolerance in the [FeFe] Hydrogenase Cb HydA1
Authors: Corrigan Patrick , Silakov Alexey
Published: May 2022

Hydrogenases are enzymes that catalyze the formation and oxidation of hydrogen. [FeFe] hydrogenases have been shown to exhibit a high efficiency of H2production, which makes these systems attractive catalysts for renewable energy generating devices. Unfortunately, this class is known for its susceptibility to oxidative degradation, thereby limiting its ability to be used in next‐generation fuel source production devices. In this presentation, we describe the first investigations of the first example of an O2‐tolerant [FeFe] hydrogenase from Clostridium beijerinkii (CbHydA1).1–3. Our FTIR measurements and activity assays show that this enzyme is able to enter an inactivate state under oxidative conditions, is stable for long periods of time in this state, and can be reactivated under reducing conditions. Using FTIR spectroelectrochemistry, we showed that this enzyme is capable of inactivating at unusually low potentials and can inactivate in the absence of oxygen or sulfide, unlike other [FeFe] hydrogenases. Using a combination of FTIR measurements and density functional theory, we are able to propose two possible chemical identities of the inactive state. Finally, we utilized advanced EPR methods to investigate the electronic structure of the active center of CbHydA1, which shed light on the electronic‐structure prerequisites of O2‐tolerance in this unusual [FeFe] hydrogenase.

(1) Morra, S.; Arizzi, M.; Valetti, F.; Gilardi, G. Oxygen Stability in the New [FeFe]‐Hydrogenase from Clostridium Beijerinckii SM10 (CbA5H). Biochemistry 2016, 55 (42), 5897–5900. https://doi.org/10.1021/acs.biochem.6b00780.

(2) Corrigan, P. S.; Tirsch, J. L.; Silakov, A. Investigation of the Unusual Ability of the [FeFe] Hydrogenase from Clostridium Beijerinckii to Access an O 2 ‐Protected State. J. Am. Chem. Soc. 2020, 142 (28), 12409–12419. https://doi.org/10.1021/jacs.0c04964.

(3) Winkler, M.; Duan, J.; Rutz, A.; Felbek, C.; Scholtysek, L.; Lampret, O.; Jaenecke, J.; Apfel, U.‐P.; Gilardi, G.; Valetti, F.; Fourmond, V.; Hofmann, E.; Léger, C.; Happe, T. A Safety Cap Protects Hydrogenase from Oxygen Attack. Nat. Commun. 2021, 12 (1), 756. https://doi.org/10.1038/s41467‐020‐20861‐2.
Orexin A enhances neuronal synchronization in adult rat hypothalamic culture: A model to study hypothalamic function
Authors: Mavanji Vijayakumar , Georgopoulos Apostolos P. , Kotz Catherine M.
Published: May 2022

Background

The regulation of sleep/wake behavior and energy homeostasis is maintained in part by the lateral hypothalamic (LH) neuropeptide orexin A (OXA, hypocretin). A reduction in orexin signaling is associated with sleep disorders and obesity, whereas higher LH orexin signaling and sensitivity promotes obesity resistance. Similarly, dysregulation of hypothalamic neural networks is associated with onset of age‐related diseases, including obesity and several neurological diseases. Despite the increase in obesity with aging, and that adult populations are the subjects in the majority of pharmaceutical and obesity studies, conventional models for neuronal networks utilize embryonic neural cultures rather than adult neurons. Synchronous activity, a feature of normal brain function, and a measure of functional connectivity, describes correlated changes in neuronal activity between neurons, Synchronization determines the nature of the final output from a given neural structure. Neural synchrony is altered by behavioral perturbations, in embryonic neurons obtained from obesity‐resistant rats, and following application of OXA onto embryonic hypothalamic cultures. Synchronous network dynamics in adult hypothalamic neurons remain largely undescribed.

Methods

We established an adult rat hypothalamic culture in multi‐electrode‐array (MEA) dishes and recorded the field potentials. Then we studied the effect of exogenous OXA on network synchronization of these adult hypothalamic cultures. In addition, we studied the wake promoting effects of OXA in vivo when directly injected into the rostral lateral hypothalamus (rLH). To study the wake promoting effects of LH OXA, rats were implanted with a radiotelemetric transmitter and EEG/EMG electrodes to record vigilance states (F40‐EET, Data Sciences International [DSI], St. Paul, MN), and a cannula targeting the rLH. Following surgical recovery, either OXA (250 pmol/0.5 μl) or saline was infused into the rLH (single injection) and sleep/wake states were measured for 2h post‐injection.

Results

The results show that adult hypothalamic cultures are viable for nearly 3 months in vitro, good quality MEA recordings can be obtained from these cultures in vitro, and finally, that cultured adult hypothalamus is responsive to OXA. In addition, LH administration of OXA enhanced wakefulness in rats, indicating that OXA enhances wakefulness for up to 2h post‐injection.

Conclusions

These results support that adult rat hypothalamic cultures could be used as a model to study the neural mechanisms underlying obesity, and that obesity resistance is associated with increased hypothalamus synchronization. Increased wake following rLH OXA suggest the possibility that OXA promotes wake partly by promoting neural synchrony in the hypothalamus.
Mitochondrial Uncoupling Decreases Sarcopenic Obesity By Activation of Skeletal Muscle Mitochondrial Quality Control and Attenuated ER Stress
Authors: Dantas Wagner S. , Zunica Elizabeth R. M. , Heintz Elizabeth C. , Hoppel Charles L. , Axelrod Christopher L. , Kirwan John P.
Published: May 2022

Background

Sarcopenic obesity is a highly prevalent disease with poor survival and ineffective medical interventions. Mitochondrial dysfunction is purported to be central in the pathogenesis of sarcopenic obesity by impairing both organelle biogenesis and quality control. We have previously identified an orally available mitochondrial‐targeted furazano[3,4‐b]pyrazine named BAM15 that selectively lowers respiratory coupling efficiency and protects against diet‐induced obesity in mice. Here, we tested the hypothesis that mitochondrial uncoupling simultaneously attenuates loss of muscle function and weight gain in a mouse model of sarcopenic obesity.

Methods

80‐week‐old male C57BL/6J mice with obesity were randomized to 10 weeks of high fat diet (CTRL) or BAM15 (BAM15; 0.1% w/w in high fat diet) treatment. Body composition, muscle function, energy expenditure, and locomotor activity were determined after treatment. Skeletal muscle was harvested and evaluated for histology, gene expression, protein signaling, and mitochondrial structure and function.

Results

BAM15 decreased body weight (~25% reduction, P<0.001) which was attributable to increased energy expenditure (~20% increment, P<0.001). BAM15 increased muscle mass (~13% increment, P<0.001), strength (~37% increment, P<0.0001), and locomotor activity (~25% increment, P<0.001). Improvements in physical function were mediated in part by reductions in skeletal muscle inflammation (IL‐6 and gp130, both P<0.05), enhanced mitochondrial function, and improved endoplasmic reticulum homeostasis and reduced inflammation. Specifically, BAM15 activated mitochondrial quality control through AMPK (PINK1‐ubiquitin binding and LC3II, P<0.01), increased electron transport chain activity (citrate synthase and complex II activity, all P<0.05), restricted endoplasmic reticulum (ER) misfolding (decreased oligomer A11 insoluble/soluble ratio, P<0.0001) while limiting ER stress (decreased PERK signaling, P<0.0001), apoptotic signaling (decreased cytochrome C release and Caspase‐3/9 activation, all P<0.001), and muscle protein degradation (decreased 14‐kDa actin fragment insoluble/soluble ratio, P<0.001).

Conclusions

Mitochondrial uncoupling agents such as BAM15 may mitigate age‐related decline in muscle mass and function by molecular and cellular bioenergetic adaptations that confer protection against sarcopenic obesity through activation of mitochondrial quality control and attenuation of ER stress.
Micro RNA Expression Profile Analysis in A549 Cancer Cells Treated with Methylsulfonylmethane
Authors: Ezenwanne Charles , Bonelli Zachary , DiLorenzo Ann Marie
Published: May 2022

Clinical and Epidemiological studies have shown a correlation between Inflammation and lung cancer. Methylsulfonylmethane (MSM) has been used for years as a dietary supplement and clinical studies have shown MSM benefits for anti‐inflammation and prevention of stress of immune cells. In particular, these studies have shown that MSM potentially induces apoptosis in cancer cell lines, and prevents the spread of cancer cells. (Kang et al. 2017) However, the specific molecular control role that MSM plays has yet to be investigated. Experiments are in progress to determine if specific MicroRNA (miRNA) can be identified and shown to be significantly altered in presence of MSM. Identification and observation of miRNA have been of interest to our lab because of its key role in the regulation of gene expression. These small non‐coding bases are known to post‐transcriptionally fine‐tune up to 30% of genes and are currently implemented in cancer‐based therapy. Specific miRNA segments have been found to be up‐regulated and down‐regulated when cells start metastasis. Our lab is exploring the possible role that MSM plays in viability, cell proliferation, and possible molecular pathways of A549 human lung cancer cells in post MSM treatment. Our preliminary studies show that MSM concentrations from 100mM to 200mM are significantly effective for initiating apoptosis and inhibiting the proliferation of A549 cells without toxicity. The apoptotic pathway seems to be an intrinsic pathway based on the data gathered so far. Further studies will indicate if miRNA is a potential molecular player in the phenotypic changes of A549 exposed to MSM. As miRNA has been a growing therapeutic target for scientists it is hoped that if there is a link between MSM and miRNA down‐regulation, this might further solidify the value of nutraceutical studies in the treatment and control of cancer.