In premenopausal women with idiopathic osteoporosis, lower bone formation rate is associated with higher body fat and higher IGF-1

We examined serum IGF-1 in premenopausal IOP, finding relationships that were opposite to those expected: higher IGF-1 was associated with lower bone formation and higher body fat, and lower BMD response to teriparatide. These paradoxical relationships between serum IGF-1, bone, and fat may contribute to the mechanism of idiopathic osteoporosis in premenopausal women.

INTRODUCTION

Premenopausal women with idiopathic osteoporosis (IOP) have marked deficits in bone microarchitecture but variable bone remodeling. We previously reported that those with low tissue-level bone formation rate (BFR) are less responsive to teriparatide and have higher serum IGF-1, a hormone anabolic for osteoblasts and other tissues. The IGF-1 data were unexpected because IGF-1 is low in other forms of low turnover osteoporosis-leading us to hypothesize that IGF-1 relationships are paradoxical in IOP. This study aimed to determine whether IOP women with low BFR have higher IGF-1 and paradoxical IGF-1 relationships in skeletal and non-skeletal tissues, and whether IGF-1 and the related measures predict teriparatide response.

METHODS

This research is an ancillary study to a 24 month clinical trial of teriparatide for IOP. Baseline assessments were related to trial outcomes: BMD, bone remodeling.

SUBJECTS

 Premenopausal women with IOP(n = 34); bone remodeling status was defined by baseline cancellous BFR/BS on bone biopsy.

MEASURES

 Serum IGF-1 parameters, compartmental adiposity (DXA, CT, MRI), serum hormones, and cardiovascular-risk-markers related to fat distribution.

RESULTS

As seen in other populations, lower BFR was associated with higher body fat and poorer teriparatide response. However, in contrast to observations in other populations, low BFR, higher body fat, and poorer teriparatide response were all related to higher IGF-1: IGF-1 Z-score was inversely related to BFR at all bone surfaces (r =  - 0.39 to - 0.46; p < 0.05), directly related to central fat (p = 0.05) and leptin (p = 0.03). IGF-1 inversely related to 24 month hip BMD %change (r =  - 0.46; p = 0.01).

CONCLUSIONS

Paradoxical IGF-1 relationships suggest that abnormal or atypical regulation of bone and fat may contribute to osteoporosis mechanisms in premenopausal IOP.

Exploring Lorentz Invariance Violation from Ultrahigh-Energy γ Rays Observed by LHAASO

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

Clinical efficacy of autogenous dentin grafts with guided bone regeneration for horizontal ridge augmentation: a prospective observational study

The aim of this study was to evaluate the efficacy of autogenous dentin grafts with guided bone regeneration (GBR) for horizontal ridge augmentation. Nineteen patients with dentition and bone defects in whom tooth/teeth extraction was indicated were recruited. Autogenous teeth were prepared, fixed on the buccal sides of the defects, and covered with bone powder and resorbable membranes before implantation. The horizontal bone mass at 0 mm (W1), 3 mm (W2), and 6 mm (W3) from the alveolar crest was recorded using cone beam computed tomography, before, immediately after, and 6 months after dentin grafting. All adverse effects were recorded. The implant stability quotient (ISQ) was measured 6 months after implantation. Twenty-eight implants were placed 6 months after dentin grafting. At this time point, the bone mass was 4.72 ± 0.72 mm (W1), 7.35 ± 1.57 mm (W2), and 8.96 ± 2.38 mm (W3), which was significantly different from that before the surgery (P < 0.05). The bone gain was 2.50 ± 0.72 mm (W1), 4.10 ± 1.42 mm (W2), and 4.56 ± 2.09 mm (W3). No soft tissue dehiscence or infection was observed. Overall, 26.3% of the patients experienced severe pain after dentin grafting. The ISQ was 78.31 ± 6.64 at 6 months after implantation. Autogenous tooth roots with GBR might be effective for horizontal ridge augmentation. This technique could be an alternative to augmentation using autogenous bone grafts.

[Evaluation of developmental toxicity of ammonium dinitramide by micromass culture and embryonic stem cells models]

Objective: To evaluated the potential developmental toxicity and teratogenicity of ammonium dinitroamide (ADN) by micromass test (MM Test) and embryonic stem cell test models. Methods: In September 2018, rat embryos were isolated and limb bud cells were collected. The limb bud cells were treated with different concentrations of ADN (0, 312.50, 625.00, 1250.00, 2500.00, 5000.00, 10000.00 μg/ml) . Half proliferation inhibitory concentration and half differentiation inhibitory concentration were calculated and the teratogenic effects were evaluated according to the criteria. For the embryonic stem cell test, the effects of different concentrations of ADN (0, 39.06, 78.13, 156.25, 312.50, 625.00, 1250.00, 2500.00 μg/ml) on the differentiation of mouse embryonic stem cells (mESCs) into myocardial cells and the cytotoxicity of mESCs and 3T3 cells were detected. The embryonic toxicity was evaluated according to the criteria. In this study, both 5-fluorouracil (5-FU) , a known strong embryonic toxic drug, and penicillin-G (P-G) , a non-embryonic toxic drug, were used to verify the effectiveness of the model, and the validated test model was applied to evaluate the embryonic toxicity of ADN. Results: In the MM Test, the inhibition rates of proliferation and differentiation of limb bud cells in ADN groups were higher than that in control group (P<0.05) . And the half proliferation inhibitory concentration and half differentiation inhibitory concentration of ADN on limb bud cells were 7480.32 and 4526.09 μg/ml, respectively. ADN was determined to be non-teratogenic by standard. In the embryonic stem cell test, the inhibition rates of mESCs proliferation in ADN groups were higher than that in control group, and the inhibition rates of 3T3 cells in 156.25, 312.50, 625.00, 1250.00, 2500.00 μg/ml ADN groups were higher than that in control group (P<0.05) . The half proliferation inhibitory concentration and half differentiation inhibitory concentration of ADN on mESCs were 1851.73 and 1796.39 μg/ml, respectively, and the half proliferation inhibitory concentration on 3T3 cells was 3334.35 μg/ml. ADN was determined to be non-embryotoxic by standard. Conclusion: After evaluation by MM Test and embryonic stem cell models, ADN has no embryo toxicity and is a non-teratogenic substance.

Relationship between Usher Syndrome and Ciliary Dysfunction in a pregnant woman with Multidrug-resistant Pneumonia: A Case Report and Literature Review

Introduction/Objective

Usher syndrome is a rare genetic disorder that consists of auditory and visual disturbances, affecting approximately 4-17 per 100,000 people. In the airways, cilia function in concert with airway mucus for mucociliary clearance, cleansing the airways of inhaled particles and pathogens. Ciliary dysfunction could lead to recurrent pulmonary infections, including from organisms resistant to more than one antibiotic. Few cases have been reported in the literature suggesting a relationship between usher syndrome and ciliary dysfunction. Hence, we would like to report an autopsy case of multidrug-resistant bacterial pneumonia in a pregnant patient with usher syndrome, discussing the possible relationship between usher syndrome, ciliary dysfunction, and multidrug-resistant pneumonia in pregnancy.

Methods/Case Report

We present a 31-year-old pregnant woman with a history of usher syndrome, hypothyroidism, and hydrocephalus presenting with shortness of breath, cough, and acute respiratory distress syndrome. She further developed refractory hypoxemia and hypercapnia complicated by multidrug-resistant bacteria infection, then intubated. Despite further management of the refractory respiratory failure, she showed no improvement. She was eventually placed on comfort care and died 49 days after she was admitted.

Results (if a Case Study enter NA)

At autopsy, the pleural surface has exudates and fibrotic adhesion. Both lungs are congested and have consolidations with variable severity on all lobes of both lungs. Microscopically, the most striking finding is the mucin accumulation in large and small airways, even in dilated alveolar spaces. There is evidence of chronic lung injury with significant interstitial fibrosis, diffuse peri-bronchial epithelial metaplasia, also with mucin accumulation. The respiratory epithelium has cilia present.

Conclusion

Although cilia were present microscopically, their function was not ascertained. The increase in progesterone during pregnancy inhibits cilia beat frequency. Therefore, the hormonal state of pregnancy and the proposed ciliary dysfunction in usher syndrome may worsen the severity of pulmonary infections seen in this patient and eventually caused her death.

Sex Differences in Proximal Thoracic Aortic Disease Pathology: A Call to Action

Introduction/Objective

Sex disparity is reported across all forms of cardiovascular diseases. Only few studies have focused on sex differences in thoracic aortic disease pathology. We aim to identify and understand sex differences in this patient group to bridge the knowledge gap and improve clinicopathologic outcomes.

Methods/Case Report

This is a retrospective analysis of 83 proximal thoracic aortic aneurysm and dissection (TAAD) cases treated at a single quaternary care center in 2019. Chart review was done for demographics. Consensus criteria (Stone JR et al. Cardiovasc Pathol 2015; 24:267-78; Halushka MK et al. Cardiovasc Pathol 2016; 25:247-57) and a scoring system (Waters KM et al. Cardiovasc Pathol 2017; 30:6-11) were used for pathology reporting. Clinical correlation was also made. Pearson’s chi-square test was used for statistical analysis.

Results (if a Case Study enter NA)

83 patients (61 male and 22 female) were retrieved. Overall thoracic aortopathy was higher among males, accounting for 73.4% of individuals with TAAD. In a subgroup analysis, there was no sex difference in dissection, aortic root involvement, and bicuspid aortic valve (p&gt;0.05). Genetic aortopathy was more prevalent in females than males (27.2% vs 9.8%, p=0.04) alongside early age at first aortic event (median age: 31y vs 52y). Histopathologically, females had frequent translamellar mucoid extracellular matrix accumulation (45.4% vs 22.9%, p=0.04), extensive (54.5% vs 27.8%, p=0.02) and severe (59% vs 34.4%, p=0.04) elastic fiber fragmentation, higher band like (9% vs 6.5%, p&gt;0.05) plus extensive (13.6% vs 4.9%, p&gt;0.05) smooth muscle nuclei loss, and extensive (13.6% vs 1.6%, p=0.01) plus dense (4.5% vs 1.6%, p&gt;0.05) laminar medial collapse than males.

Conclusion

In our patient population, females have a lower prevalence of thoracic aortic disease treated with open repair. However, those who develop TAAD harbor a greater burden of wall pathology and probable worse outcomes. We recommend sex-based analysis of all research on thoracic aortic diseases.

The first case of BRG (SMARCA4)/INI Deficient Tracheal Carcinoma: A Case Report and Review of the Literature

Introduction/Objective

Primary tumors of the trachea are rare, they account for less than 0.1% of tumors in humans. In adults, 90% of primary tracheal tumors are malignant, with squamous cell carcinoma and adenoid cystic carcinoma accounting for two-thirds, with other forms occurring less frequently. The BRG (SMARCA4)/INI deficient tumor is a relatively new defined entity which is recently introduced in the WHO Classification of Tumors, 5th edition, 2021. The gene SMARCA4 is located at 19p13. Loss of SMARCA4 has been reported in several aggressive tumors with high- grade undifferentiated rhabdoid morphology but has not been reported in the trachea. Hence, we report the first case of BRG (SMARCA4)/ INI deficient tracheal carcinoma.

Methods/Case Report

We present a 60-year-old male with a history of tobacco abuse, shortness of breath, and a tracheal mass on chest imaging. Bronchoscopy was performed and showed a fleshy friable lesion at the anterior trachea with evidence of blood dripping into the distal airways.

Results (if a Case Study enter NA)

Microscopic examination showed a high grade, poorly differentiated carcinoma with tumor necrosis, high mitotic counts, and marked nuclear pleomorphism. Immunohistochemical stains were performed. The tumor cells were strongly and diffusely positive for CK-7 and weakly positive for synaptophysin, negative for pan-cytokeratin, TTF-1, CK-20, p40, CK5/6, and chromogranin. Then BRG (SMARCA4) and INI 1 (BAR47) were performed and showed negative staining on BRG expression, while INI 1 is intact (nuclear expression). These features are consistent with BRG (SMARCA4)/ INI deficient carcinoma.

Conclusion

BRG (SMARCA4)/ INI deficient carcinoma is a new entity in the trachea, which is very aggressive with a poor prognosis. Targeted therapy or clinical trials may be available as additional cases are diagnosed in the future.

Expression and clinical significance of MMP-9 and P53 in lung cancer

OBJECTIVE

This study aimed to investigate the expression of MMP-9 (matrix metalloproteinases 9) and P53 (tumor suppressor proteins, tumor protein P53) in serum of patients with lung cancer. The relation between the two factors and their clinical pathological features were also explored.

PATIENTS AND METHODS

150 patients were selected as the experimental group. They were diagnosed with lung cancer in Shandong Province Chest Hospital from January 2014 to January 2017. Meanwhile, 90 healthy subjects were selected as the control group. The expression levels of MMP-9 and P53 in serum were detected by fluorescence quantitative Real-Time Polymerase Chain Reaction (RT-PCR). The diagnostic value of MMP-9 and P53 in patients with lung cancer was analyzed by receiver operating characteristic curve (ROC). Pearson test was used to analyze the correlation between MMP-9 and P53 in the experimental group. The patients were divided into high expression and low expression groups according to the median of MMP-9 and P53 expressions.

RESULTS

The expressions of MMP-9 and P53 in patients with lung cancer were higher than the normal level (p<0.05). MMP-9 and P53 in serum of the experimental group were closely related to patients' TNM-stage, degree of differentiation, lymph node metastases, smoking history and pattern of organization (p<0.05). The expressions of MMP-9 and P53 were positively correlated (p<0.001).

CONCLUSIONS

The expressions of MMP-9 and P53 played important roles in lung cancer and were closely related to clinicopathology and three-year survival rate. They could provide help for the diagnosis and treatment of clinical lung cancer.

LINC00483 is regulated by IGF2BP1 and participates in the progression of breast cancer

OBJECTIVE

To explore the role of long intergenic non-coding ribonucleic acid 483 (LINC00483) in the development of breast cancer (BC) and its possible mechanism of action.

PATIENTS AND METHODS

LINC00483 expression level in BC tissues and cell lines was detected via quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR). The association between LINC00483 expression and survival rate of BC patients was analyzed using Kaplan-Meier survival analysis. The binding relation between LINC00483 and insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) was verified via RNA immunoprecipitation (RIP) and RNA pull-down assays. The expression of IGF2BP1 in BC patients was determined using qRT-PCR. Moreover, the role of LINC00483 on the proliferative ability of BC cells was detected via cell counting kit-8 (CCK8) and 5-Ethynyl-2'-deoxyuridine (EdU) assays. Whether LINC00483 exerts its effects under the regulation of IGF2BP1 was verified via reversal assay.

RESULTS

The results of qRT-PCR showed that LINC00483 had a significantly high expression in BC tissues and corresponding cell lines, and it rose with the increase in tumor stage, which was higher in patients with metastasis. CCK8/EdU assay revealed that the proliferative ability of MDA-MB-231 and MCF-7 cell lines was enhanced by overexpression of LINC00483. It was confirmed by RIP and pull-down assays that IGF2BP1 could bind to LINC00483, and the expression of LINC00483 was significantly promoted after up-regulation of IGF2BP1. It was found via qRT-PCR that the expression of IGF2BP1 evidently rose in BC patients, which was positively related with the expression level of LINC00483. The results of reversal assay manifested that the function of LINC00483 on cell proliferation was regulated by IGF2BP1.

CONCLUSIONS

LINC00483 has a significantly higher expression in BC tissues than that in para-carcinoma tissues, and its effect of promoting proliferation of BC cells may be regulated by IGF2BP1.

The clinical characteristic of biliary-hyperlipidemic etiologically complex type of acute pancreatitis: a retrospective study from a tertiary center in China

OBJECTIVE

Biliary and hyperlipidemic acute pancreatitis (AP) has become the second most common AP in China. Currently, AP is exclusively diagnosed as biliary or hyperlipidemic AP. However, as suggested by some reports, biliary and hyperlipidemic AP might coexist in a single patient. Moreover, acute lipotoxicity was shown to regulate the severity of biliary AP in the mouse model. Thus, whether these two etiologies coexist in AP patients and potentially worsen the clinical course remains unclear. To elucidate the clinical feature of a new complex type of acute pancreatitis with both biliary and hyperlipidemic etiologies.

PATIENTS AND METHODS

This retrospective study included AP patients who were admitted into our department within 7 days after the onset of the disease. 267 AP patients were enrolled in this study and were classified as BAP (biliary acute pancreatitis, n=153), HLAP (hyperlipidemic acute pancreatitis, n=65) and BHAP (biliary-hyperlipidemic acute pancreatitis, n=49). All the enrolled patients met the classification criteria of biliary etiology, hyperlipidemic etiology, and both etiologies, respectively. BHAP was compared with BAP and HLAP in terms of general information, inflammatory biomarkers, organ dysfunction, disease severity and clinical outcomes.

RESULTS

BHAP (41 vs. 53) patients were younger than BAP patients. Serum procalcitonin of BHAP patients was higher than BAP and HLAP patients. Serum CRP of BHAP patients was higher than BAP patients. BHAP patients had the highest diagnosis rate of severe acute pancreatitis (SAP) (46.9% vs. 17.6% or 21.5%) compared to BAP and HLAP. Prevalences of persistent respiratory, acute renal, and circulatory failure were highest in BHAP patients (44.9%, 28.6%, 12.2%, respectively). Requirements for mechanical ventilation, renal replacement therapy and vasoactive agents were also highest in BHAP patients (36.7%, 34.7%, 12.2%, respectively). Hospital stay was longer in BHAP patients (33 days) compared with BAP patients (24 days).

CONCLUSIONS

Patients with both biliary and hyperlipidemic etiologies suffer from more severe clinical course of the disease and have worse prognosis than single-etiology BAP or HLAP patients in the early stage of AP (within 7 days). It should be recognized as a new etiological type named biliary-hyperlipidemic acute pancreatitis (BHAP).

Pathogenic Variants in ACTRT1 Cause Acephalic Spermatozoa Syndrome

Acephalic spermatozoa syndrome is a rare type of teratozoospermia, but its pathogenesis is largely unknown. Here, we performed whole-exome sequencing for 34 patients with acephalic spermatozoa syndrome and identified pathogenic variants in the X-linked gene, ACTRT1, in two patients. Sanger sequencing confirmed the pathogenic variants of ACTRT1 in the patients. Both pathogenic variants of ACTRT1 were highly conserved, and in silico analysis revealed that they were deleterious and rare. Actrt1-knockout mice exhibited a similar acephalic spermatozoa phenotype. Therefore, we speculated that mutations in ACTRT1 account for acephalic spermatozoa syndrome. Moreover, the patients in this study conceived their children through artificial insemination. This study provides further insights for clinicians and researchers regarding the genetic etiology and therapeutic strategies for acephalic spermatozoa patients with pathogenic variants in ACTRT1.

Peta-electron volt gamma-ray emission from the Crab Nebula

The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10^-4 to 1.1 peta-electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta-electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron's size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta-electron volt electrons, 2.5 × 10³⁶ ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta-electron volt protons to the production of the highest-energy gamma rays.

Correlations of Helicobacter pylori with liver function, inflammatory factors and serum levels of FoxP3 and RORγt in patients with hepatitis B cirrhosis

OBJECTIVE

To investigate the correlations of Helicobacter pylori (HP) with liver function, inflammatory factors and serum levels of forkhead box P3 (FoxP3) and retinoic acid receptor-related orphan receptor gamma-t (RORγt) in patients with hepatitis B cirrhosis (HBC).

PATIENTS AND METHODS

A total of 60 HBC patients were divided into HBC group (n=30) and HP-infected HBC group (HP&HBC group, n=30). QRT-PCR was conducted to determine the messenger ribonucleic acid (mRNA) levels of FoxP3 and RORγt in serum samples. ELISA was applied to measure the levels of relevant inflammatory factors. Besides, immunohistochemical staining was conducted to detect positive expressions of FoxP3 and RORγt in liver tissues of patients in the two groups.

RESULTS

No significant differences in gender, drinking, smoking, diabetes and age were found between HBC group and HP&HBC group (p>0.05). Globulin and albumin levels were comparable between the two groups (p>0.05). Liver function indexes, including ALT, AST and TBIL were higher in HP&HBC group than those in HBC group (p<0.05). The HBV-DNA level was lower in HBC group in comparison with that in HP&HBC group. The interferon-gamma (IFN-γ) level was remarkably higher in HBC group than that in HP&HBC group (p<0.01), and the levels of interleukin (IL)-6, IL-10, IL-17 and transforming growth factor (TGF)-β1 were notably lower in HBC group in comparison with those in HP&HBC group (p<0.01). Additionally, the mRNA levels of FoxP3 and RORγt in HBC group were distinctly lower than those in HP&HBC group (p<0.01). The mRNA levels of FoxP3 and RORγt were positively related to those of IL-6, IL-10, IL-17, and TGF-β1, and negatively associated with IFN-γ level. Immunohistochemical results indicated that positive expression rates of FoxP3 and RORγt in the liver tissues were approximately 50% in HP&HBC group and B. Zhao, Q.-J. Sheng, Y. Qin, X.-L. Wang, H. Zhao, N. Zhaowere 15% in HBC group, and the difference was statistically significant (p<0.05).

CONCLUSIONS

Expression levels of FoxP3 and RORγt in serum and liver tissues are elevated in HP-infected HBC patients, and inflammatory factors are correlated with their expressions, suggesting the aggravated liver damage.

Standardization in Quantitative Imaging: A Multicenter Comparison of Radiomic Features from Different Software Packages on Digital Reference Objects and Patient Data Sets

Radiomic features are being increasingly studied for clinical applications. We aimed to assess the agreement among radiomic features when computed by several groups by using different software packages under very tightly controlled conditions, which included standardized feature definitions and common image data sets. Ten sites (9 from the NCI's Quantitative Imaging Network] positron emission tomography–computed tomography working group plus one site from outside that group) participated in this project. Nine common quantitative imaging features were selected for comparison including features that describe morphology, intensity, shape, and texture. The common image data sets were: three 3D digital reference objects (DROs) and 10 patient image scans from the Lung Image Database Consortium data set using a specific lesion in each scan. Each object (DRO or lesion) was accompanied by an already-defined volume of interest, from which the features were calculated. Feature values for each object (DRO or lesion) were reported. The coefficient of variation (CV), expressed as a percentage, was calculated across software packages for each feature on each object. Thirteen sets of results were obtained for the DROs and patient data sets. Five of the 9 features showed excellent agreement with CV < 1%; 1 feature had moderate agreement (CV < 10%), and 3 features had larger variations (CV ≥ 10%) even after attempts at harmonization of feature calculations. This work highlights the value of feature definition standardization as well as the need to further clarify definitions for some features.

Selective optogenetic stimulation of glutamatergic, but not GABAergic, vestibular nuclei neurons induces immediate and reversible postural imbalance in mice

Glutamatergic and GABAergic neurons represent the neural components of the medial vestibular nuclei. We assessed the functional role of glutamatergic and GABAergic neuronal pathways arising from the vestibular nuclei (VN) in the maintenance of gait and balance by optogenetically stimulating the VN in VGluT2-cre and GAD2-cre mice. We demonstrate that glutamatergic, but not GABAergic VN neuronal subpopulation is responsible for immediate and strong posturo-locomotor deficits, comparable to unilateral vestibular deafferentation models. During optogenetic stimulation, the support surface dramatically increased in VN^VGluT2+ mice, and rapidly fell back to baseline after stimulation, whilst it remained unchanged during similar stimulation of VN^GAD2+ mice. This effect persisted when vestibular tactilo kinesthesic plantar inputs were removed. Posturo-locomotor alterations evoked in VN^VGluT2+ animals were still present immediately after stimulation, while they disappeared 1 h later. Overall, these results indicate a fundamental role for VN^VGluT2+ neurons in balance and posturo-locomotor functions, but not for VN^GAD2+ neurons, in this specific context. This new optogenetic approach will be useful to characterize the role of the different VN neuronal populations involved in vestibular physiology and pathophysiology.

Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622+3749 Observed by LHAASO-KM2A

We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E>25  TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17_{stat}±0.02_{sys}. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160  TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.

Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 γ-ray Galactic sources

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 10¹⁵ electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays¹. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. ²). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane^3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

A88 PATIENT AND PHYSICIAN PERSPECTIVE OF TELE-HEALTH IN GASTROENTEROLOGY

Background

Given the social distancing measures employed to reduce the transmission of SARS-CoV-2, tele-health has rapidly expanded and is now routinely used in new patient encounters and in follow up appointments across Canada.

Aims

To determine the patient and physician perspective towards tele-health in a gastroenterology outpatient setting.

Methods

An anonymous voluntary online survey was distributed to patients who had previously undergone at least one tele-health visit in a tertiary care gastroenterology outpatient setting. A separate online survey was distributed to gastroenterologists practising across Canada.

Results

A total of 181 patients from British Columbia (59.8% female) completed the survey. The tele-health appointment was the first visit for 21.8% of patients. Appointments occurred by phone call alone (61.4%) or by video and audio software (38.6%) and started within 5 minutes of the scheduled time in 75% of visits. Patient satisfaction with the tele-health visit was high (8.54 on a scale of 0–10; 0 completely dissatisfied, 10 extremely satisfied; IQR 8–10). Most patients did not perceive a difference in likelihood of compliance compared to a non-tele-health visit (90.6%), were not concerned about the lack of physical exam during a tele-health visit (82.4%) and did not with-hold information they would have revealed in person (88.7%). After the COVID-19 pandemic, some patients would prefer tele-heath visits (39.2%), whereas others would prefer in office visits (28.5%) and the remainder were indifferent (32.3%). Post-pandemic, most patients would prefer tele-health for follow up visits (68.4%), over tele-health for all possible visits (27.9%) or no tele-health visits (3.8%).

A total of 25 Canadian gastroenterologists (28.0% female; 60% academic practice, 40% community practice) completed a separate survey. Regarding the lack of physical exam in tele-health, 44% of physicians believed this did not affect the quality of their assessment, whereas some physicians believed it had either minimally (48%) or greatly (8%) impaired the quality of their assessment. Almost all physicians (96%) perceived that patients either appreciate tele-health as much as or more than in office visits.

Post-pandemic, most physicians (96%) supported a hybrid model of both tele-health and in office visits. Appointments for follow up of benign endoscopic pathology results (96%), follow up visits (92%), consultations prior to endoscopy (76%) were deemed to be most appropriate for tele-health. Follow up of malignant pathology results (24%) and consultations for new patients (32%) were thought to be less appropriate for tele-health visits.

Conclusions

Patient and physician satisfaction with tele-health in a Canadian outpatient gastroenterology setting is high. Most patients and physicians wish for tele-health to remain available in the post-pandemic setting.

Funding Agencies

Gastrointestinal Research Institute, Vancouver, British Columbia

A83 IMPACT OF TELEHEALTH ON MEDICATION ADHERENCE IN GASTROENTEROLOGY CHRONIC DISEASE MANAGEMENT

Background

With the COVID-19 pandemic, the demand and availability of telehealth in outpatient care has increased. Although use of telehealth has been studied and validated for various medical specialties, relatively few studies have looked at its role in gastroenterology despite burden of chronic diseases such as inflammatory bowel disease (IBD).

Aims

To assess effectiveness of telehealth medicine in gastroenterology by comparing medication adherence rate for patients seen with telehealth and traditional in-person appointment for various GI conditions.

Methods

Retrospective chart analysis of patients seen in outpatient gastroenterology clinic was performed to identify patients who were given prescription to fill either through telehealth or in-person appointment. By using provincial pharmacy database, we determined the prescription fill rate.

Results

A total of 241 patients were identified who were provided prescriptions during visit with their gastroenterologists. 128 patients were seen through in-person visit during pre-pandemic period. 113 patients were seen through telehealth appointment during COVID pandemic.

The mean age of patients in telehealth cohort was 42 years (57% male). On average patients had 10 prior visits with their gastroenterologists before index appointment, used for adherence assessment. 92% of patients were seen in follow-up, while 8% were seen in initial consultation. The majority of the patients in the telehealth cohort had IBD (89%), while the remaining 11% had various diagnoses, including functional GI disorder, gastroesophageal reflux disease, viral hepatitis, or hepatobiliary disorders. Biologic therapy was the most commonly prescribed medication (66.4%). 45 patients were provided either new medication or dose change, and 68 patients had prescription refill to continue their current medications. It took a mean of 18 days (SD = 16.2) for patients to fill their prescriptions.

Prescription fill rate for patients seen through telehealth and in-person visit were 98.2% and 89.1% (P = 0.004) respectively. Patients seen through telehealth were 6.8 times more likely to fill their prescriptions compared to the in-person counterparts (OR 6.82, CI 1.51 – 30.68, P = 0.004). When we compared adherence rate while excluding biologic therapies, the prescription fill rate was 94.7% in telehealth group and 81.4% in in-person group (OR 4.11, CI 0.88 – 19.27, P = 0.056). Due to high level of adherence, statistical analysis comparing adherent and non-adherent groups was performed but yielded insignificant results.

Conclusions

Medication adherence rate for patients seen through telehealth was higher compared to patients seen through in-patient visit in this study. Telehealth is a viable alternative for outpatient care especially for patients with chronic GI conditions such as IBD.

Funding Agencies

None

MiR-33a inhibits the adipogenic differentiation of ovine adipose-derived stromal vascular fraction cells by targeting SIRT6

Adipose tissue is important for the regulation of energy balance through its metabolic, cellular, and endocrine functions. Furthermore, the excessive storage of subcutaneous fat can seriously affect the health and carcass traits of domestic animals. Stromal vascular fraction (SVF) cell adipogenic differentiation increases the number of differentiated adipocytes and plays a role in lipid deposition. The adipogenic differentiation of SVF cells is regulated by various factors, including microRNAs and cytokines. Sirt6 and miR-33a are known to be involved in metabolism and adipogenesis, respectively; however, their effects on the adipogenic differentiation of ovine SVF cells were previously unknown. Thus, the aim of this study was to investigate this. The results showed that SIRT6 is a binding target for miR-33a. Moreover, overexpression or inhibition of miR-33a was found to change the expression of SIRT6 messenger RNA and protein. Furthermore, modulating SIRT6 altered the expression of adipogenic marker genes. In addition, miR-33a and SIRT6 were found to play opposing roles in adipogenesis. Specifically, we demonstrated that miR-33a is involved in the negative regulation of ovine SVF cell adipogenic differentiation by inhibiting the expression of SIRT6. These findings reveal a key role for miR-33a and SIRT6 in adipogenesis, which will enrich our understanding of the regulatory factors associated with SVF cell adipogenic differentiation and provide a basis for further study on this process.