bluuebunny/crossref_metadata_2025 huggingface dataset:
Financial Conflicts of Interest in Propensity Score-Matched Studies Evaluating Biologics and Biosimilars for Inflammatory Bowel Disease
Authors: Elsolh Karam , Tham Daniel , Scaffidi Michael A , Gimpaya Nikko , Bansal Rishi , Torabi Nazi , Li Juana , Verma Yash , Khan Rishad , Grover Samir C
Published: May 2022

Background

Propensity score matching (PSM), a statistical technique that estimates a treatment effect by accounting for predictor covariates, has been used to evaluate biologics for inflammatory bowel disease (IBD). Financial conflicts of interest are prevalent in the marketing of biologic medications. It is unclear whether this burden of conflicts is present among authors of PSM studies comparing IBD biologics and biosimilars.

Objective

This study was aimed to determine the prevalence of financial conflicts of interest among authors of PSM studies evaluating IBD biologics and biosimilars.

Methods

We conducted a systematic search for PSM studies comparing biologics and biosimilars in IBD treatment. We identified 21 eligible studies. Two independent authors extracted self-declared conflicts from the disclosures section. Each participating author was searched on the Centers for Medicare & Medicaid Services Open Payments to identify payment amounts and undisclosed conflicts. Primary outcome was the prevalence of author conflicts. Secondary analyses assessed for an association between conflict prevalence and reporting of positive outcomes.

Results

Among 283 authors, conflicts were present among 41.0% (116 of 283). Twenty-three per cent (27 of 116) of author conflicts involved undisclosed payments. Studies with positive outcomes were significantly more likely to include conflicted authors than neutral studies (relative risk = 2.34, 95% confidence interval: 1.71 to 3.21, P < 0.001).

Conclusions

Overall, we found a high burden of undisclosed conflicts among authors of PSM studies comparing IBD biologics and biosimilars. Given the importance of PSM studies as a means for biologic comparison and the potential for undue industry influence from these payments, authors should ensure greater transparency with reporting of industry relationships.
Structural insights reveal the specific recognition of meiRNA by the Mei2 protein
Authors: Shen Siyuan , Jian Yanze , Cai Zhaokui , Li Fudong , Lv Mengqi , Liu Yongrui , Wu Jihui , Fu Chuanhai , Shi Yunyu
Published: May 2022

In the fission yeast Schizosaccharomyces pombe, Mei2, an RNA-binding protein essential for entry into meiosis, regulates meiosis initiation. Mei2 binds to a specific non-coding RNA species, meiRNA, and accumulates at the sme2 gene locus, which encodes meiRNA. Previous research has shown that the Mei2 C-terminal RNA recognition motif (RRM3) physically interacts with the meiRNA 5′ region in vitro and stimulates meiosis in vivo. However, the underlying mechanisms still remain elusive. We first employed an in vitro crosslinking and immunoprecipitation sequencing (CLIP–seq) assay and demonstrated a preference for U-rich motifs of meiRNA by Mei2 RRM3. We then solved the crystal structures of Mei2 RRM3 in the apo form and complex with an 8mer RNA fragment, derived from meiRNA, as detected by in vitro CLIP–seq. These results provide structural insights into the Mei2 RRM3–meiRNA complex and reveal that Mei2 RRM3 binds specifically to the UUC(U) sequence. Furthermore, a structure-based Mei2 mutation, Mei2F644A causes defective karyogamy, suggesting an essential role of the RNA-binding ability of Mei2 in regulating meiosis.
Public service motivation, role stress, and job burnout of police post-COVID-19: A study of the police in Taipei City in Taiwan
Authors: Chiu Jeng-Tzu , Chou Po-Pin , Wang Chun-Yuan
Published: May 2022

As the outbreak of COVID-19 has spread rapidly in Taiwan in 2021, police have more arduous tasks to fulfil. High-stress police workloads and long working times cause high job stresses that make them physically and mentally tired, eventually leading to job burnout (JB). Previous research refers that JB is caused by role stress (RS). Yet public service motivation (PSM) focuses on an individual’s service motivation to work in public organizations regarded as an inherent value of civil servants. This leads to our research questions as follows: Will police role stressors affect job burnout? How does public service motivation affect police stress and job burnout? This study conducted a questionnaire survey of frontline police in Taipei City, confirmed that job burnout is generally an extension of pressure caused by role stress. In addition, this study has shown public service motivation has a moderating effect on job burnout. Therefore, the government can provide more resources and benefits for the police to increase their motivation for public services, and indeed alleviate job burnout.
Intraspecific Growth and Aflatoxin Inhibition Responses to Atoxigenic Aspergillus flavus: Evidence of Secreted, Inhibitory Substances in Biocontrol
Authors: Sweany Rebecca R. , DeRobertis Catherine D. , Kaller Michael D. , Damann Kenneth E.
Published: May 2022

The fungus Aspergillus flavus infects corn, peanut, and cottonseed, and contaminates seeds with acutely poisonous and carcinogenic aflatoxin. Aflatoxin contamination is a perennial threat in tropical and subtropical climates. Nonaflatoxin-producing isolates (atoxigenic) are deployed in fields to mitigate aflatoxin contamination. The biocontrol competitively excludes toxigenic A. flavus via direct replacement and thigmoregulated (touch) toxin inhibition mechanisms. To understand the broad-spectrum toxin inhibition, toxigenic isolates representing different mating types and sclerotia sizes were individually cocultured with different atoxigenic biocontrol isolates. To determine whether more inhibitory isolates had a competitive advantage to displace or touch inhibit toxigenic isolates, biomass accumulation rates were determined for each isolate. Finally, to determine whether atoxigenic isolates could inhibit aflatoxin production without touch, atoxigenic isolates were grown separated from a single toxigenic isolate by a membrane. Atoxigenic isolates 17, Af36, and K49 had superior abilities to inhibit toxin production. Small (<400 µm) sclerotial, Mat1-1 isolates were not as completely inhibited as others by most atoxigenic isolates. As expected for both direct replacement and touch inhibition, the fastest-growing atoxigenic isolates inhibited aflatoxin production the most, except for atoxigenic Af36 and K49. Aflatoxin production was inhibited when toxigenic and atoxigenic isolates were grown separately, especially by slow-growing atoxigenic Af36 and K49. Additionally, fungus-free filtrates from atoxigenic cultures inhibited aflatoxin production. Toxin production inhibition without direct contact revealed secretion of diffusible chemicals as an additional biocontrol mechanism. Biocontrol formulations should be improved by identifying isolates with broad-spectrum, high-inhibition capabilities and production of secreted inhibitory chemicals.
Roles for CCN proteins in Lysophosphatidic Acid and Sphingosine 1‐Phosphate Signaling in Prostate Cancer Cells
Authors: Balijepalli Pravita , Knode Brianna K. , Nahulu Samuel A. , Meier Kathryn E.
Published: May 2022

Introduction

Cysteine rich angiogenic factor (CCN1/Cyr61) and connective tissue growth factor (CCN2/CTGF) are members of the CCN family of matricellular proteins. These secreted proteins interact with extracellular matrix proteins and integrins to modulate cell signaling. CCN proteins have been implicated in survival and other mitogenic responses in various cancers. CCN1 and CCN2 are the two early inducible genes in this family. Lysophosphatidic acid (LPA) and sphingosine‐1‐phosphate (S1P) are lipid growth factors known to contribute to tumor progression in prostate cancer. In previous work, our group showed that LPA stimulates proliferation and migration in prostate cancer cells via the G protein‐coupled receptor LPAR1. Free fatty acid receptor 4 (FFAR4) agonists, inhibit LPA‐induced responses in prostate cancer cells. We also demonstrated that CCN1 expression is induced by LPA in human prostate cancer cells. However, the roles of CCN1 and CCN2 in cancer cell signaling have not been fully elucidated.

Hypothesis

We hypothesize that CCN proteins contribute to LPA‐ and S1P‐induced adhesion and mitogenic signaling in prostate cancer cells.

Methods and Results

PC‐3 human prostate cancer cells were used in the current study. For all experiments, cells were serum starved for 24 hours and then treated with and without 10 µM LPA or S1P. Immunoblotting showed that CCN1 and CCN2 were induced by LPA after 2‐5 hours in PC‐3 cells. The response was inhibited by the LPA receptor antagonist Ki1625. TUG‐891, an FFAR4 agonist, inhibited LPA‐induced CCN1 expression in PC‐3 cells. S1P also induced CCN1 expression in PC‐3 cells. In related experiments, whole cell extracts, and extracellular matrix were subjected to immunoblotting for CCN1, and immunofluorescence microscopy was used to localize the induced CCN1. CCN1 protein levels in extracellular matrix were increased 2‐5 hours after LPA treatment, as compared to untreated controls, and CCN1 was detected outside the cells by confocal microscopy. In cell adhesion assays, LPA‐treated PC‐3 cells exhibited an increase in adhesion to fibronectin‐coated 96‐well plates that was detected by 2 hours. Erk MAPK activation in response to LPA was biphasic, with the later phase occurring after CCN1/2 induction.

Conclusion

The results of this study suggest that CCN proteins may play roles in LPA‐ and S1P‐induced signaling in prostate cancer cells and are thus potential therapeutic targets.
Post‐Pubertal Testosterone Implants Induce Hypertension in Female‐to‐Male Trans‐Sex Rat Model
Authors: Shawky Noha M. , Yanes Cardozo Licy , Reckelhoff Jane F.
Published: May 2022

Introduction

Androgens induce increases in blood pressure (BP) and risk of cardiovascular diseases (CVDs) in females, as seen in polycystic ovary syndrome females. However, it is not clear whether treatment with gender‐affirming hormone therapy in trans‐men have an impact on their BP or risk of CVD. Therefore, the present study was undertaken to test the hypothesis that chronic androgen supplements (starting post pubertal) in a rodent model of transgender men, will increase BP and promote metabolic dysfunction.

Methods

Female SD rats were implanted with testosterone propionate (TP, 7.5 mg in 5 mm silastic tubes, replaced every 3 wks, n = 10) starting at 7 wks of age (post‐puberty) and compared to controls (empty silastic implants, n = 10). Rats were weighed weekly. Radiotelemetry transmitters were implanted at 13 wks of age (n = 5‐6/group) and mean arterial pressure (MAP) was measured at 15, 21 and 25 wks of age. Body composition was determined at 15, 21 and 23 wks of age and proteinuria was determined at 15 and 21 wks of age (n = 4/group). Serum testosterone was measured by LC/MS at 15 wks of age (n = 4/group). Oral glucose tolerance test was performed at 11 and 22 wks of age (n = 4/group).

Results

TP supplements increased serum testosterone at 15 wks of age by 30‐fold compared to female controls (6.4 ± 1.5 vs 0.2 ± 0.05 ng/ml, respectively; p<0.005). Body weight (BW) increased significantly in TP group compared to controls by 10 wks of age (241 ± 4 g vs 220 ± 2 g, respectively; p<0.05) and was sustained through 26 wks of age (311 ± 7 g vs 276 ± 5 g, respectively; p<0.05). Fat mass and fat mass/BW were similar between TP and controls. Lean mass was significantly higher in TP group compared to controls at 15, 21 and 23 wks of age (254 ± 7, 268 ± 12 and 273 ± 12 g vs 218 ± 6, 227 ± 5 and 229 ± 5 g, respectively; p<0.01); however, when factored for BW, there were no differences between TP and controls. Proteinuria was significantly higher in TP group compared to controls at 15 wks of age (4.9 ± 1.2 vs 2.1 ± 0.3 mg/24 h, respectively, p<0.05) and 21 wks of age (7.6 ± 1.1 vs 2.4 ± 0.5 mg/24 h, respectively, p<0.005). Importantly, MAP was increased significantly in TP group at 15 wks of age (112 ± 3 vs 106 ± 4 mmHg, p<0.05), 21 wks of age (114 ± 3 vs 105 ± 2 mmHg; p<0.05) and 24 wks of age (115 ± 3 vs 104 ± 2 mmHg, p<0.05), compared to controls, respectively. Oral glucose tolerance test at 11 and 22 wks of age was similar between groups.

Conclusion

Testosterone used in a form of sex‐affirming therapy in female rats induced increases in BP that are independent of adiposity or Insulin resistance and maybe associated to renal injury. Future studies should determine whether these changes are sustained with aging, and the mechanisms responsible for the increase in BP in the female‐to‐male trans‐sex model.
Angiotensin‐(1‐7) Mas Receptors Localized to Proopiomelanocortin Neurons Tonically Regulate Insulin Sensitivity
Authors: Mehay Darren , Bingaman Sarah , Silberman Yuval , Arnold Amy C.
Published: May 2022

Angiotensin (Ang)‐(1‐7), a protective hormone of the renin‐angiotensin system, has emerged as a novel target to improve cardiovascular and metabolic functions in animal models. In addition to blood pressure lowering effects, recent studies from our laboratory and others have shown that Ang‐(1‐7) can promote insulin sensitization and weight loss in obese rodents. Our recent preliminary findings suggest these effects are centrally‐mediated, with Ang‐(1‐7) mas receptors (MasR) widely distributed to the arcuate nucleus of the hypothalamus. In particular, we found that MasR are highly colocalized with proopiomelanocortin (POMC)‐containing neurons in this brain region, neurons which when activated reduce food intake and increase energy expenditure to promote weight loss as well as improve insulin sensitivity. The importance of MasR localized to POMC neurons in metabolic functions, however, is currently unknown. In this study, we tested the hypothesis MasR expressed in POMC neurons are important for normal control of energy balance and glucose homeostasis. To test this, mice containing conditional knockout alleles of the Ang‐(1‐7) MasR were crossed with POMC‐Cre mice to specifically delete MasR from POMC neurons (POMCMasR‐KO). Body mass and composition, insulin sensitivity, and glucose tolerance were measured in male and female POMCMasR‐KO mice and wild‐type littermates (n=6‐11/group) at 8 weeks of age on a standard chow diet. Despite similar fasting glucose and insulin levels, male POMCMasR‐KO mice had worsened insulin sensitivity compared with wild‐type littermates (area under the curve for decrease in glucose from baseline in response to intraperitoneal insulin: ‐2134±1071 vs. ‐6531±1507, respectively; p=0.029), with no differences in body mass, adiposity, lean mass, or glucose tolerance. In female mice, there was no effect of POMC MasR deletion on any of the metabolic outcomes tested. These findings suggest that MasR localized to POMC neurons provide tonic and sex‐specific modulation of insulin sensitivity in mice. Additional studies are needed to determine if altered MasR signaling in POMC neurons could contribute to insulin resistance in disease states such as obesity and type II diabetes.
Inhibition of human ERα‐positive breast carcinoma cell by baicalein via cell cycle arrest and apoptosis
Authors: Epelle Lovelyn , Woerner Benjamin , Strawn Miguel T. G. , Monear Nicodemus C. , Nelson Tristan H. , Xhabija Besa
Published: May 2022

Baicalein is a naturally occurring flavone found in the four herbaceous plants: Scutellaria baicalensis, Scutellaria lateriflora, Oroxylum indicum, and the well‐known species Thymus vulgaris (thyme). Recently recognized as a potential anticancer therapeutic agent, baicalein is gaining popularity in cancer research laboratories. However, it is unclear whether baicalein can inhibit cancerous properties of the human ERα‐positive breast carcinoma cell line T47D. Here we demonstrate that baicalein can significantly inhibit cell growth and proliferation. Additionally, cell cycle analysis reveals that baicalein inhibits T47D breast cancer cell growth by inducing cell cycle arrest, suppressing colony formation and cell migration. Additionally, baicalein was shown to induce cell death by regulating genes and interacting with signaling pathways involved in apoptosis. These studies clearly suggest that baicalein has potent anti‐cancer properties and has great potential for cancer therapy.
Antimicrobial and cytotoxicity effect of gum Arabic‐silver nanoparticles
Authors: Ahmed Omnia A. K. , Ahmed Omnia A. K.
Published: May 2022

Objective

The objective of this study was to test the antimicrobial and cytotoxicity effect of silver nanoparticles (AgNPs) manufactured by means of green synthesis using gum Arabic against microorganisms associated with oral biofilm.

Methods

Two types of AgNPs (4g/1g) were synthesized from gum Arabic powder (GA). These GA‐AgNPs were characterized via UV‐Vis spectral analysis, DLS, FTIR, and TEM. Additionally, the stability of both GA‐AgNPs was tested in artificial media representing the condition on the oral cavity. Subsequently, their antimicrobial activity was tested against S.sanguinis, S.mutans, L.acidophilus,and C.albicansusing disc diffusion method. Their minimum inhibitory concentrations (MICs) were established. Finally, cytotoxicity was tested on the buccal mucosa fibroblast cells (BMF) using MTT assay.

Results

Both GA‐AgNPs were spherical, ranging between 10‐20nm in diameter and were more stable in Mullier Hinton Broth compared to the other media tested. 4gGA‐AgNPs had relatively comparable zones of inhibition to chlorohexidine, whereas those for 1gAgNPs were negligible. The average MIC90 & MIC50 for 4gAgNPs range between 3.125‐12.5µg/ml, with 25‐100µg/ml for 1gGA‐AgNPs. The 1gGA‐AgNPs had more than 60% survival below 25µg/ml, while 4gGA‐AgNPs was below 3.125µg/ml.

Conclusion

4gGA‐AgNPs showed the highest antimicrobial activity against the tested oral microbes, however with higher cytotoxicity that needs to be reduced for further dental application.
Inhalation Exposure to Airborne PM2.5Induces Integrated Organelle Stress Response in the Liver
Authors: Zhang Kezhong , Grossman Lawrence I. , Stemmer Paul M. , Kim Hyunbae , Carruthers Nicholas
Published: May 2022

Air pollution is a sustained problem of public health for the general population. Accumulating evidence has confirmed a significant association between exposure to fine ambient particulate matter with aerodynamic diameters < 2.5 μm (PM2.5) and the increase of morbidity and mortality associated with cardiovascular and metabolic diseases. Chronic inflammation and dysregulated energy metabolism have been identified as the driving force of the PM2.5‐caused pathogenesis. However, a precise understanding of the molecular and cellular mechanisms by which PM2.5induces inflammatory stress responses and impairs energy homeostasis remains elusive. Research in our laboratory has addressed the mechanistic basis underlying the pathophysiologic effects of PM2.5exposure on liver and adipose tissues with mouse models under inhalation exposure to environmentally relevant PM2.5. Proteomics analysis with PM2.5‐exposed mouse liver tissues indicated that mitochondria and endoplasmic reticulum (ER) are the most sensitive organelles in transducing signaling cascades upon PM2.5stimulation. Further investigation revealed that inhalation exposure to PM2.5induces an integrated ER stress and mitochondrial stress response in mouse livers. Under PM2.5exposure, the ER and mitochondria interact and build up a platform through Mitochondria‐Associated Membranes (MAMs) to augment an integrated inflammatory stress response, mediated through the primary ER stress sensor IRE1α and Toll‐like receptor (TLR) 2 and 4. This integrated organelle stress response pathway promoted non‐alcoholic steatohepatitis (NASH), characterized by hepatic inflammation, steatosis and fibrogenesis, hepatic glycogen depletion, and insulin resistance in PM2.5‐exposed mice. Disruption of MAMs by knockdown of the MAM‐residing ER chaperone Sigma‐1 Receptor (Sig‐1R) or mitofusin (MNF2) in Kupffer cells or hepatocytes suppressed PM2.5‐induced NASH and insulin resistance in mice. Together, our studies suggested that exposure to airborne PM2.5pollution activates an integrated ER and mitochondrial stress response in the liver, which promotes NASH, disrupts energy homeostasis, and impairs insulin signaling associated with the development of metabolic syndrome. These findings provide significant insights into the hepatic pathways underlying PM2.5‐triggered liver pathology, and have important implications in the understanding, prevention, and treatment of air pollution‐associated metabolic disease.
Citronellol exerts lung protective and anti‐inflammatory effects through hampering NF‐κB in lipopolysaccharide‐induced acute lung injury in mice
Authors: Redha Samah M. , Kathem Sarmed H.
Published: May 2022

Background

Acute lung injury (ALI) is one of the most serious conditions characterized by an exacerbation of inflammatory response in the lungs that can result from lung infection. Citronellol, a natural monoterpenoid found in citronella oil and other natural sources. In this study, the lung protective and anti‐inflammatory effects of citronellol were investigated in ALI induced by Lipopolysaccharide (LPS) in mice.

Method

adult mice were allocated into groups, control mice received normal saline. Mice in the induction group received LPS 10mg/kg/day intraperitoneally and euthanized 2 hours later. Mice in the treatment groups received either 50mg or 100mg/kg/day of oral citronellol for 5 consecutive days prior to LPS injection.

Results

Pretreatment with citronellol (50mg/kg/day) attenuated lung inflammatory events as observed from the significant reduction of TNF‐α (6.02±1.039 vs 29.20±4.77) and COX2 (4.12±0.23 vs 10.58±0.77) mRNA expressions in lung tissue compared to non‐treated mice. Interestingly, increasing the dose of citronellol to 100mg/kg/day also resulted in a significant reduction in both TNF‐α (3.30±0.745 vs 29.20±4.77) and COX2 (4.62±0.58 vs 10.58±0.77) mRNA expression compared to non‐treated mice.

Looking for the upstream events revealed that NF‐κB gene expression was significantly hampered by citronellol 50mg/kg/day (5.11 ± 1.096 vs 11.88±1.57) and 100mg/kg/day (3.22± 0.253 vs 11.88±1.57) compared to non‐treated mice. Analysis of the data revealed that the effect of citronellol were dose dependent in terms of TNF‐α and NF‐κB gene expression.

Conclusion

This study clearly revealed that citronellol exerted anti‐inflammatory and lung‐protective effects in LPS‐induced acute lung injury. The observed effects were dose‐independent and resulted through hampering of NF‐κB pathway.
OmpF porins of Enterobacteriaceae possess amyloidogenic properties
Authors: Belousov Mikhail V. , Kosolapova Anastasiia O. , Sulatskaya Anna I. , Sulatsky Maksim I. , Antonets Kirill S. , Nizhnikov Anton A.
Published: May 2022

Outer membrane porins represent an important group of bacterial virulence associated proteins, whose amyloidogenic properties are actively investigated. Amyloids are protein fibrils with highly ordered beta‐sheet‐rich spatial structure and unique physicochemical properties including unusual resistance to treatment with different detergents and proteases. In prokaryotes, at least ten different functional groups of functional amyloids have been identified. Several outer membrane porins of gram‐negative bacteria were shown to adopt amyloid state. In this study, we analyzed amyloid properties of the OmpF porins of Escherichia coli and Salmonella enteritidis species which are known to be associated with the virulence and pathogenic properties of these bacteria in humans and animals. Our data show that recombinant OmpF proteins form fibrils with morphology typical for amyloids. The in vitro obtained aggregates of OmpF demonstrate resistance to treatment with cold ionic detergents and proteases. Moreover, these aggregates bind amyloid‐specific dye thioflavin T and exhibit apple‐green birefringence in polarized light upon staining with Congo Red dye. Overall, these data confirm the amyloidogenic properties of the OmpF porins of E. coli and S. enteritidis in vitro and suggest that these proteins could represent novel functional bacterial amyloids probably associated with pathogen‐host interactions.
A novel histogram based on the SEER database predicts overall survival in patients with high‐grade cerebellar glioma
Authors: Duan Hubin , Hao Chunyan , Zhang Yu , Qiao Binjun , Jing Zhijie , Chen Xianghui , Zheng Juan , Qiao Xiaohong
Published: May 2022

Objective

High‐grade cerebellar gliomas are clinically challenging to treat, and there is a relative lack of large sample statistics as a prognostic criterion. In order to compare changes in patient survival under different conditions, we screened the risk factors that affecting survival in patients with high‐grade cerebellar gliomas, developed Nomograms and verified their accuracy.

Methods

Patients with high‐grade cerebellar glioma from 1975 to 2016 were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database, excluding patients with no biopsy or surgery, unknown tissue type, grade, or survival data, then coded patient data for classification and processed, and a prediction group and a validation group were randomly assigned using the CARET procedure in R (4.0.2). We use univariate and multivariate Cox regression models to screen variables that were significantly related to the prognosis of patients with high‐grade cerebellar glioma, and these variables were then used to construct Nomogram. Secondly, we use the consistency index (C‐index), receiver operating characteristic curve (ROC), calibration chart and decision curve analysis (DCA) to analytically validate the accuracy of the Nomogram model. Finally, Kaplan‐Meier survival analysis was used to test the prognostic indicators of Nomogram.

Results

A total of 197 patients with high‐grade cerebellar glioma were selected from the SEER database, and the patient data were categorized and coded into a prediction group (n = 100) and a validation group (n = 97). Univariate and multivariate Cox regression models were used to obtain four statistically significant indices of age, tumor type, type of surgery, and radiation therapy, which were then used to construct Nomogram with a C‐index of 0.830 (95% CI: 0.765‐0.895) for the prediction group and 0.789 (95% CI: 0.715‐0.863) for the validation group.

Conclusion

Nomograms have promising clinical applicability and more accurate predictive outcome. For patients with cerebellar glioma, radiotherapy and surgical resection are definitive in improving prognosis. Older patients tend to die earlier, and the pathological type is also a key factor in prognosis.
GAL3 Excretion Regulates Smooth Muscle Cell Survival and Proliferation
Authors: Haigh Stephen , Li Xi , Bordan Zsuzsanna , Sellers Hunter , Meadows Mary Louise , Barman Scott , Fulton David
Published: May 2022

Pulmonary arterial hypertension (PAH) is a complex and fatal disorder characterized by an unrelenting increase in pulmonary arterial pressure. Excessive proliferation of pulmonary artery smooth muscle cells (PASMC) leads to increased vascular resistance and eventually right ventricular failure and death. Our laboratory has identified a key role for Galectin‐3 (GAL‐3) in PAH. However, the mechanisms by which GAL‐3 alters PASMC behavior remains poorly understood. GAL‐3 contains a functional BH1 like domain that has an NWGR sequence with high homology to the anti‐apoptotic protein, BCL2, and this domain has previously been shown to be functional in cancer cell lines. Our hypothesis is GAL‐3 upregulation plays an important role in driving PASMC proliferation through repression of apoptosis via this NWGR domain. Using adenoviral vector encoding the GAL‐3 G182A mutation and isolated GAL‐3 PASMCs from a GAL3 KO rat (RPASMC). Our in vitro studies show that overexpression of GAL‐3 G182A causes a decrease in viability upon treatment overnight with 0.5% serum containing media(p<.001) compared to normal media (p=.840). When exposed to apoptotic stimuli (TNFα, Cycloheximide) GAL‐3 G182A overexpressing GAL‐3 KO RPASMCs had significantly (p<.001) decreased vitality. Interestingly however, this domain also seems to regulate non‐apoptotic related events such as cell attachment. Our previous work had shown that GAL‐3 is readily excreted protein, and co‐culture experiments as well as recombinant protein supplementation show that soluble GAL‐3 is biologically active and induces SMC growth and proliferation(P<.05). Further experimentation also shows that inhibition of GAL‐3 using blocking antibodies prevents SMC proliferation. (p<.05) To test this hypothesis in‐vivo we injected GAL‐3 KO mice with a liver specific AAV overexpressing GAL‐3, or GFP (control) and exposed them to sugen/hypoxia to induce PAH. Surprisingly our initial findings indicate a slight protection with liver GAL‐3 overexpression when compared to wt mice.(p<.05) Also very interestingly, while liver overexpression of GAL‐3 was very high there was no evidence of GAL3 in the lungs or plasma of GAL3KO mice indicating it may not be secreted from the liver in sufficient amounts unlike what was observed in other cell types. Overall our data suggests that the NWGR domain of GAL‐3 is an important regulator of PASMC survivability and the blocking antibody suggests that secreted GAL‐3 is capable of regulating SMC proliferation, however it does not appear that hepatocytes secrete sufficient GAL‐3 for it to circulate and play a role in the lung vasculature.
Selection and development of aptamers for pyoverdine
Authors: Anisuzzaman Sharif , Banerjee Soma , Jiang Nianyu , Shrotriya Pranav , Nilsen‐Hamilton Marit
Published: May 2022

The rhizosphere is a small region surrounding plant roots that is enriched in biochemicals from root exudates and populated with fungi, nematode, and bacteria. Interaction of rhizosphere organisms with plants is mainly promoted by exudates from the roots. Root exudates contain biochemicals that come from primary and secondary metabolisms of plants. These biochemicals attract microbes, which influence plant nutrition. The rhizosphere bacteria (microbiome) are vital to plant nutrient uptake and influence biotic and abiotic stress and pathogenesis. Pseudomonas is a genus of gammaproteobacteria known for its ubiquitous presence in natural habitats and its striking ecological, metabolic, and biochemical diversity. Within the genus, members of the Pseudomonas fluorescens group are common inhabitants of soil and plant surfaces, and certain strains function in the biological control of plant disease, protecting plants from infection by soilborne and aerial plant pathogens. The soil bacterium Pseudomonas protegens Pf‐5 (also known as Pseudomonas fluorescensPf‐5) is a well‐characterized biological strain, which is distinguished by its prolific production of the secondary metabolite, pyoverdine. Knowledge of the distribution of P. fluorescens secretory activity around plant roots is very important for understanding the interaction between P. fluorescens and plants and can be achieved by real time tracking of pyoverdine. To achieve the capability of real‐time tracking in soil, we have used a structure‐switching SELEX strategy to select high affinity ssDNA and 2’ F‐Y‐RNA aptamers with specificity for pyoverdine over other siderophores. Pyoverdines from various strains possess a conserved chromophore along with strain‐specific peptide chain. Some of the isolated aptamers bind to chromophore of pyoverdine. These will identify pyoverdines from a variety of pseudomonads. Identification of aptamers that selectively bind the peptide portion of pyoverdine Pf‐5 is underway. The identified aptamers that are broadly and narrowly specific for pyoverdines or Pf‐5 will be optimized for integration into an electrochemical biosensor to track, in real time, P fluorescens activity and other pseudomonads in and around the rhizosphere.
Regulation of the Age‐Dependent Activity of the FOXO Transcription Factor DAF‐16 in Adult Caenorhabditis elegans Roundworms
Authors: Graczyk Nicole , Youngman Matthew
Published: May 2022

The insulin and insulin‐like growth factor signaling (IIS) pathway regulates stress resistance and contributes to longevity in evolutionarily diverse species. In the roundworm Caenorhabditis elegans the lifespan of daf‐2 mutants, which lack functional insulin receptors, is twice that of wildtype animals. This phenotype is entirely dependent upon the FOXO transcription factor DAF‐16. In the absence of negative regulation through the IIS pathway, DAF‐16 upregulates genes important for stress resistance, defense, and repair. While it can be activated in response to environmental insults, in young animals DAF‐16 is normally inhibited. However, we and others have demonstrated that the activity of DAF‐16 increases in an age‐dependent manner. The mechanism by which DAF‐16 is regulated during aging has not yet been defined. Here we used a reverse genetic approach in C. elegans to investigate the function of genes that act upstream in the insulin signaling pathway to ask about their potential roles in modulating DAF‐16 activity in post‐reproductive adult animals. We tested the hypothesis that activation of DAF‐2 and the ensuing activation of the PDK‐1 kinase must be blocked in order to permit DAF‐16 to regulate its transcriptional targets. By analyzing the expression of a GFP‐labeled transcriptional reporter and by measuring gene expression levels by qRT‐PCR, we found that in an age‐dependent manner DAF‐18, an ortholog of mammalian PTEN that prevents PDK‐1 from being activated, is necessary for the increased expression of DAF‐16 targets over time. Further, we found that RNAi targeting daf‐18 reduced the ability of adult but not larval stage animals to resist infection by the bacterial pathogen Pseudomonas aeruginosa. This indicates that DAF‐18 is required for DAF‐16‐mediated innate immunity later in life. Our observations raise the intriguing possibility that an agonist engages DAF‐2 to initiate signaling through the IIS pathway at the same time that DAF‐16 is activated during adulthood. Previous studies established a role for micro RNAs (miRNAs) in regulating DAF‐2 activity, and we asked whether this could be true in the context of aging by knocking down the expression of alg‐2, an argonaute protein involved in miRNA biogenesis. We reasoned that expression of a DAF‐2 ligand might be controlled post‐transcriptionally by miRNA. Our functional analysis implies a possible genetic interaction between alg‐2 and daf‐18 that is most evident in adult C. elegans, suggesting that their gene products may act in the same pathway that ultimately governs DAF‐16 function. Together, our results reveal elements of a transcriptional regulatory mechanism that is specific to adult animals and that involves evolutionarily conserved components, suggesting its general relevance to the aging process in diverse organisms.
Characterizing the Correlation Between Angiogenesis and Osteogenesis In Vivo Using Multicontrast Functional Imaging in a Calvarial Defect Model
Authors: Ren Yunke , Bhargava Akanksha , Senarathna Janaka , Chu Xinying , Grayson Warren , Pathak Arvind
Published: May 2022

Angiogenesis is a key factor in bone healing that allows the delivery of oxygen, nutrients, inflammatory and bone precursor cells to the defect site. It induces dramatic structural and functional remodeling of the vasculature during the first 4 weeks of bone healing. Although recent advances in optical imaging have elucidated the in vivo relationship between angiogenesis and osteogenesis in a calvarial defect model, these efforts were mostly limited to structural imaging of the vasculature and bone. Therefore, to better characterize changes in vascular function (i.e. blood flow, oxygenation, etc.) during the bone healing cascade we developed a multicontrast optical imaging framework to assess in vivo changes in microvascular architecture using intrinsic optical signal (IOS) imaging; changes in blood flow with laser speckle contrast (LSC) imaging; and bone formation with bright‐field imaging at high spatial (5 µm) and temporal (200 ms) resolutions. With this system we acquired multicontrast images from 10 animals with calvarial defects every 2 days, over 4 weeks (Fig. 1a, d). The bone and vasculature were then digitally segmented from the bright‐field and IOS images for quantitative analysis (Fig. 1b, c). We also euthanized an animal each week for assessing 3D changes in bone volume and vascular architecture using an ex vivo, high‐resolution (10 µm) CT imaging workflow we recently developed called VascuViz (Fig. 2a, b, d). Using this framework, we demonstrated that angiogenic remodeling within the bone defect microenvironment was most robust from post injury day (D) 4 to D10, during which blood vessel length, volume and density all showed significant increase (Fig. 2c). The blood flow exhibited a sudden increase at D6 when angiogenesis started, and the angiogenic vessels were most perfused at D12 (Fig. 1d). These vascular changes peaked by the end of week 2 and plateaued during the next 2 weeks which were correlated with a large increase in bone volume during the first 2 weeks and smaller increase during the last 2 weeks (Fig. 2e). These results indicate that both structural and functional changes of the microvascular system strongly correlate with bone growth during the early stages of bone healing.

Next, we plan to include additional indices of vascular function such as vessel maturity and intravascular oxygenation, as well as image‐based hemodynamic models to further characterize the role of the vascular microenvironment during osteogenesis. We believe that this novel imaging framework for characterizing the defect microenvironment can be utilized to inform the design of novel tissue engineering (TE) constructs for craniofacial bone regeneration. Collectively, these advances herald a new era of “image‐based TE”.
Elucidating the cellular mechanism of methionine toxicity
Authors: Pitsch Emily , Hughes Adam
Published: May 2022

Cells possess several mechanisms to maintain amino acid homeostasis including regulation of amino acid permease trafficking, protein synthesis, metabolic reactions, and storage within the lysosome or vacuole. With aging and in certain diseases these processes are impaired, leading to a toxic accumulation of amino acids. While it is well‐established that excess amino acids are problematic for cells, it is poorly understood how individual amino acids drive cellular dysfunction and how cells combat toxic levels of these metabolites. To begin to elucidate cellular mechanisms of amino acid toxicity, we focused our analysis on methionine, because of its unique role in translation, metabolism, and as a precursor for the methyl donor, s‐adenosylmethionine. Additionally, methionine restriction has been shown to extend lifespan and delay progression or improve disease phenotypes, suggesting that methionine itself can be problematic to organisms.

To study methionine toxicity, we first identified yeast strains that were sensitive to the amino acid. We genetically modulated pathways cells use to traffic two amino acid permeases – the high‐affinity methionine permease (Mup1) and the general amino acid permease (Gap1). These permeases are targeted for removal from the plasma membrane by ubiquitination of N‐terminal lysine residues, which is facilitated by an α‐arrestin protein. Mup1 internalization was inhibited by knocking out the α‐arrestin, LDB19, and Gap1 internalization was blocked usingGAP1K9R,K16R. Compared to wildtype, these mutants were greatly sensitized to exogenous methionine, measured by growth inhibition, highlighting the importance of modulating methionine levels to maintain cellular health. To explore mechanisms of methionine toxicity, we conducted RNA‐sequencing and found that excess methionine leads to an upregulation of genes under transcriptional regulation of Hsf1 and Gcn4. These transcription factors are activated in response to disruptions in protein homeostasis and tRNA charging, respectively. In addition to Hsf1 activation, we observed aggregation of heat shock proteins, Hsp104 and Hsp42, via fluorescent microscopy. Genetic depletion of Hsf1 using a tet‐repressible allele led to diminished growth on methionine compared to control cells, suggesting there is an increased requirement for Hsf1 when cells are exposed to excess methionine. Finally, we found a decrease in total protein when cells are exposed to excess methionine. This could be explained by the activation of Gcn4 which is activated in response to alternations in tRNA homeostasis and would reduce translation rates.

The reasons for methionine toxicity are currently unknown, but our data suggests that excess methionine drives proteotoxicity and may perturb tRNA charging homeostasis. This work provides us with preliminary evidence for the mechanisms through which methionine imparts toxicity and how cells respond to excess levels of this amino acid.
Interleukin‐8 (IL‐8) as a Potential Mediator of an Association Between Trimethylamine N‐Oxide (TMAO) and Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) among African‐Americans at Risk for Cardiovascular Disease
Authors: Baginski Alyssa , Farmer Nicole , Baumer Yvonne , Wallen Gwenyth R. , Powell‐Wiley Tiffany
Published: May 2022

Trimethylamine N‐Oxide (TMAO) is a microbial metabolite derived from the hepatic‐gut axis and linked to inflammation and cardiovascular disease (CVD). Studies have shown that TMAO is linked to CVD and its risk factor hyperlipidemia by enhanced macrophage foam cell formation or alterations in reverse cholesterol transport. Other mechanisms have not been reported to date. Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) is a largely hepatic expressed protein that blocks Low Density Lipoprotein (LDL) receptor recycling, leading to hyperlipidemia. The primary objective of this study was to investigate a potential relationship between TMAO and PCSK9 in order to explore a novel mechanism linking TMAO and CVD risk. We hypothesized that TMAO and PCSK9 would have a direct association among a sample of African American adults, a population at increased risk for CVD, and that this relationship would be mediated by inflammatory cytokines.

African‐American adults at risk for CVD living in the Washington, DC area were recruited to participate in a cross‐sectional community‐based study that involved clinical examination and collection of fasting blood samples. Serum samples were analyzed for clinical CVD risk factors. Fasting levels of inflammatory cytokines (interleukin (IL)‐1 beta, tumor necrosis factor‐alpha, and interleukin‐8), TMAO, and PCSK9 were measured using Luminex and ELISA, respectively. Univariate and multivariate linear regression analyses and structural equation mediation analyses were conducted using STATA. All models were adjusted for body mass index (BMI) and atherosclerotic CVD risk score (ASCVD).

The participant sample (n = 60) included a majority of self‐identified African‐American women (93.33%), who presented as obese (Mean BMI = 33). A significant association between TMAO and PCSK9 was identified in both unadjusted (β = 0.30, p = 0.02) and adjusted (β = 0.31, p =0.02) models. Both TMAO and PCSK9 were significantly associated with IL‐8 (TMAO: β = 0.45, p = 0.00; PCSK9: β = 0.23, p = 0.05) in adjusted models. Mediation analysis indicated that 34.77% of the relationship between TMAO and PCSK9 was explained by IL‐8 (Figure 1).

Our findings indicate a potential PCSK9 involved pathway for TMAO and CVD risk. Furthermore, our results suggest this pathway is mediated by the inflammatory cytokine, IL‐8. Future studies may identify the role of dietary or stress‐related factors that could increase IL‐8 and potentially influence the TMAO‐PCKSK9 relationship.
The Influence of Covid‐19‐Based mRNA Vaccines on Measures of Conduit Artery and Microvascular Endothelial Function
Authors: Serviente Corinna , Matias Alexs , Erol Muhammet E. , Calderone Mia , Layec Gwenael
Published: May 2022

With the emergence of severe acute respiratory syndrome 2 (SARS‐CoV‐2), leading to coronavirus disease 19 (COVID‐19), a new class of messenger RNA (mRNA) vaccines have been broadly used. These vaccines have been associated with inflammatory sides effects such as myo‐ and peri‐carditis. Despite the well‐known link between inflammation and endothelial dysfunction, it is unknown whether these vaccines may transiently impair endothelial function, and therefore increase cardiovascular risk. Aim: To evaluate the influence of COVID‐19‐based mRNA vaccines on macro‐ and micro‐vascular endothelial function in healthy adults. We hypothesized that macro‐ and micro‐vascular endothelial function would be reduced following vaccination.

Methods

Prior to, and ~48 hrs following the second dose of COVID‐19‐based mRNA vaccines, brachial artery flow‐mediated dilation (FMD, macrovascular function), reactive hyperemia (microvascular function), and cutaneous intradermal microdialysis coupled with laser Doppler flowmetry (microvascular function) were measured in healthy young adults. For microdialysis, a standard local heating protocol (42⁰C) was utilized, followed by infusion of the Nitric Oxide Synthase inhibitor Nω‐Nitro‐L‐arginine methyl ester hydrochloride (L‐NAME, 15mM), and induction of maximum vasodilation (43⁰C+28mM Sodium Nitroprusside). Sites included: control (lactated Ringer’s), ascorbic acid (10 mM), l‐arginine (10 mM), and tetrahydrobiopterin (BH4,10 mM). C‐reactive protein (CRP), a marker of systemic inflammation, was measured from fasting serum samples at both time points.

Results

Vaccination (mRNA‐1273, n=3 and BNT162b2, n=6, 5men/4women, 34±2yrs) induced an increase in CRP (pre: 0.2±0.1mg/dL vs. post: 2.1±0.5mg/dL, p=0.008, r‐statistic=‐0.89), but had no effect on FMD (pre: 3.6±0.9% vs. post: 4.6±1.1%, p=0.43, Cohen’s d=0.28) or reactive hyperemia (pre: 20178±3236 AU vs. post: 28426±4573 AU, p=0.14, Cohen’s d=0.55). There was no association between the change in FMD (r=‐0.07, p=0.87) or reactive hyperemia (r=‐0.48, p=0.19) and the change in CRP. Vaccination also had no effect on microvascular nitric oxide (NO)‐dependent dilation (pre: 77.0±2.5% vs post: 77.3±2.4%, p=0.91, ηp2=0.002), nor was there an effect of microdialysis treatment on NO‐dependent dilation (p=0.74, ηp2=0.05). Following vaccination, the difference in NO‐dependent dilation relative to control was unaffected by treatment (p=0.25, η2=0.11) with no difference in the effects of BH4 (6.3±4.9%), l‐arginine (8.3±5.2%), or ascorbic acid (‐2.6±4.2%, all p>0.05). The change in NO‐dependent dilation at the control site was not related to the change in CRP (r=0.32, p=0.40).

Conclusions

There was a significant inflammatory response to COVID‐19‐based mRNA vaccines ~48 hrs following the second vaccine dose. Despite this, macro‐ and micro‐vascular endothelial function and NO‐dependent dilation were preserved in healthy adults.