Testing the Limitations of MD-Based Local Electric Fields Using the Vibrational Stark Effect in Solution: Penicillin G as a Test Case

Noncovalent interactions underlie nearly all molecular processes in the condensed phase from solvation to catalysis. Their quantification within a physically consistent framework remains challenging. Experimental vibrational Stark effect (VSE)-based solvatochromism can be combined with molecular dynamics (MD) simulations to quantify the electrostatic forces in solute-solvent interactions for small rigid molecules and, by extension, when these solutes bind in enzyme active sites. While generalizing this approach toward more complex (bio)molecules, such as the conformationally flexible and charged penicillin G (PenG), we were surprised to observe inconsistencies in MD-based electric fields. Combining synthesis, VSE spectroscopy, and computational methods, we provide an intimate view on the origins of these discrepancies. We observe that the electric fields are correlated to conformation-dependent effects of the flexible PenG side chain, including both the local solvation structure and solute conformational sampling in MD. Additionally, we identified that MD-based electric fields are consistently overestimated in three-point water models in the vicinity of charged groups; this cannot be entirely ameliorated using polarizable force fields (AMOEBA) or advanced water models. This work demonstrates the value of the VSE as a direct method for experiment-guided refinements of MD force fields and establishes a general reductionist approach to calibrating vibrational probes for complex (bio)molecules.

The relationship between intestinal flora changes and osteoporosis in rats with inflammatory bowel disease and the improvement effect of probiotics

OBJECTIVE

The aim of this study was to investigate the relationship between the changes in intestinal flora and the occurrence of osteoporosis in rats with inflammatory bowel disease and the improvement effect of probiotics.

MATERIALS AND METHODS

A total of 100 Sprague Dawley (SD) model rats with colitis were selected as research objects. All rats were randomly divided into two groups, including: bowel disease group and osteoporosis group, with 50 rats in each group. Stool samples were collected from all rats, and Lactobacillus, Escherichia coli and Bifidobacteria were cultured and counted. The relationship between the occurrence of related osteoporosis and intestinal flora was analyzed as well. Thereafter, the rats in osteoporosis group were randomly divided into two subgroups, namely, control group (n=25) and observation group (n=25). Observation group was treated with probiotics by gastrogavage, while the control group was treated with the same volume of physiological saline. Next, the changes in serum osteoprotegerin (OPG), osteoprotegerin ligand [receptor activator of nuclear factor-kappa B ligand (RANKL)], procollagen type I carboxy-terminal propeptide (PICP), bone mineral density (BMD), bone alkaline phosphatase (BALP), tartrate-resistant acid phosphatase (TRACP), calcium concentration (Ca), and inflammatory cytokine levels were compared between the two groups after intervention.

RESULTS

Osteoporosis group had significantly more Escherichia coli and notably fewer Lactobacillus and Bifidobacteria than bowel disease group (p<0.05). Pearson correlation analysis revealed that the occurrence of osteoporosis in rats with inflammatory bowel disease was negatively correlated with the count of Escherichia coli, whereas was positively related to the counts of Lactobacillus and Bifidobacteria (p<0.05). Moreover, the levels of serum OPG, PICP, TRACP, and Ca in observation group were remarkably higher than those in the control group (p<0.05). However, the levels of serum RANKL, BALP, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and interferon-gamma (INF-γ) were markedly lower than those in the control group (p<0.05).

CONCLUSIONS

Osteoporosis in rats with inflammatory bowel disease has a negative association with the count of Escherichia coli, and a positive correlation with the counts of Lactobacillus and Bifidobacteria. In addition, treatment with probiotics can effectively alleviate osteoporosis symptoms in rats with inflammatory bowel disease by influencing the level of corresponding cytokines.

Accurate diagnosis of colorectal cancer based on histopathology images using artificial intelligence

BACKGROUND

Accurate and robust pathological image analysis for colorectal cancer (CRC) diagnosis is time-consuming and knowledge-intensive, but is essential for CRC patients' treatment. The current heavy workload of pathologists in clinics/hospitals may easily lead to unconscious misdiagnosis of CRC based on daily image analyses.

METHODS

Based on a state-of-the-art transfer-learned deep convolutional neural network in artificial intelligence (AI), we proposed a novel patch aggregation strategy for clinic CRC diagnosis using weakly labeled pathological whole-slide image (WSI) patches. This approach was trained and validated using an unprecedented and enormously large number of 170,099 patches, > 14,680 WSIs, from > 9631 subjects that covered diverse and representative clinical cases from multi-independent-sources across China, the USA, and Germany.

RESULTS

Our innovative AI tool consistently and nearly perfectly agreed with (average Kappa statistic 0.896) and even often better than most of the experienced expert pathologists when tested in diagnosing CRC WSIs from multicenters. The average area under the receiver operating characteristics curve (AUC) of AI was greater than that of the pathologists (0.988 vs 0.970) and achieved the best performance among the application of other AI methods to CRC diagnosis. Our AI-generated heatmap highlights the image regions of cancer tissue/cells.

CONCLUSIONS

This first-ever generalizable AI system can handle large amounts of WSIs consistently and robustly without potential bias due to fatigue commonly experienced by clinical pathologists. It will drastically alleviate the heavy clinical burden of daily pathology diagnosis and improve the treatment for CRC patients. This tool is generalizable to other cancer diagnosis based on image recognition.

Properties of Heavy Secondary Fluorine Cosmic Rays: Results from the Alpha Magnetic Spectrometer

Precise knowledge of the charge and rigidity dependence of the secondary cosmic ray fluxes and the secondary-to-primary flux ratios is essential in the understanding of cosmic ray propagation. We report the properties of heavy secondary cosmic ray fluorine F in the rigidity R range 2.15 GV to 2.9 TV based on 0.29 million events collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. The fluorine spectrum deviates from a single power law above 200 GV. The heavier secondary-to-primary F/Si flux ratio rigidity dependence is distinctly different from the lighter B/O (or B/C) rigidity dependence. In particular, above 10 GV, the F/Si/B/O ratio can be described by a power law R^{δ} with δ=0.052±0.007. This shows that the propagation properties of heavy cosmic rays, from F to Si, are different from those of light cosmic rays, from He to O, and that the secondary cosmic rays have two classes.

Properties of Iron Primary Cosmic Rays: Results from the Alpha Magnetic Spectrometer

We report the observation of new properties of primary iron (Fe) cosmic rays in the rigidity range 2.65 GV to 3.0 TV with 0.62×10^{6} iron nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. Above 80.5 GV the rigidity dependence of the cosmic ray Fe flux is identical to the rigidity dependence of the primary cosmic ray He, C, and O fluxes, with the Fe/O flux ratio being constant at 0.155±0.006. This shows that unexpectedly Fe and He, C, and O belong to the same class of primary cosmic rays which is different from the primary cosmic rays Ne, Mg, and Si class.

COX-2/PGE2 facilitates fracture healing by activating the Wnt/β-catenin signaling pathway

OBJECTIVE

The aim of this study was to explore the influence of cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) on fracture healing by activating the Wnt/β-catenin signaling pathway.

MATERIALS AND METHODS

In this study, 36 adult Sprague-Dawley (SD) rats raised in our laboratory were selected as research objects. The rats were subjected to fracture surgery on the middle part of the right femoral shaft. Subsequently, they were randomly divided into the control group and experimental groups (including experimental group A and experimental group B). Rats in experimental group A were injected with PGE 2 or COX-2 selective inhibitor NS-398, while rats in experimental group B were injected with PGE2 (5 μmol/L). Meanwhile, rats in the control group were injected with the same amount of normal saline. After that, the transcriptional levels of PEG2, COX-2, vascular endothelial growth factor (VEGF) and β-catenin in rats of the experimental group A, experimental group B and control group were detected via fluorescence quantitative Polymerase Chain Reaction (PCR) assay. Enzyme-linked immunosorbent assay (ELISA) and Western blotting were conducted to determine the changes in protein levels of PEG2, COX-2, VEGF and β-catenin in rats of the experimental group A, experimental group B and control group. The expression level of VEGF in bone tissues at fracture ends of rats in the experimental group A, experimental group B and control group was observed through the hematoxylin-eosin (HE) staining. Furthermore, micro-computed tomography (CT) was employed to evaluate callus formation.

RESULTS

The transcriptional and translational levels of COX-2, β-catenin and VEGF in rats of experimental group A treated with COX-2 inhibitors were significantly down-regulated when compared with those of the control group, showing statistically significant differences (p<0.05). However, the levels of these genes were markedly elevated in the experimental group B treated with PGE2 in comparison with those in the control group, and the differences were statistically significant (p<0.05). After 6 weeks, HE staining showed that the expression level of VEGF in rats of the experimental group B was remarkably higher than that of the experimental group A (p<0.05). Micro-CT results revealed that the mean trabecular plate density (MTPD) of rats in the experimental group B (73.29±5.4) was markedly higher than the number of osteoblasts (49.6±3.9) in the experimental group A, showing a statistically significant difference (p<0.05).

CONCLUSIONS

COX-2/PGE2 facilitates fracture healing by activating the Wnt/β-catenin signaling pathway.

Donepezil markedly prevents the progression of chronic heart failure and renal dysfunction in renal artery stenosis-induced hypertensive rats

Introduction

Parasympathetic activation by donepezil has been shown to improve prognosis in chronic heart failure (CHF) rats following myocardial infarction. We examined whether donepezil is effective in the treatment of another CHF model complicated with renal artery stenosis (RAS)-induced hypertension.

Methods

RAS was created by ligating the left renal artery up to 50% in SD rats, at the same time, we implanted a blood pressure (BP) transmitter for confirming RAS-induced hypertension (7-week post-RAS: systolic BP = 154±7 mmHg; diastolic BP = 115±8 mmHg). In the 11th week after induction of RAS, surviving animals were randomly assigned to untreated (UT, n=10) or donepezil treated [DT, n=10, dissolved in drinking water (3mg/kg/day)] group. After a 6-week treatment, the effects of donepezil were evaluated by hemodynamics, blood levels of neurohumoral markers, and morphology.

Results

Compared with UT, DT significantly prevented the progression of the left kidney atrophy (2.38±0.13 vs. 1.51±0.34 g/kg, P&lt;0.05) and kidney fibrosis (left: −64%, P&lt;0.001; right: −55%, P&lt;0.01). DT also significantly prevented the progression of CHF, through suppressing cardiac hypertrophy (2.30±0.06 vs. 2.57±0.08 g/kg, P&lt;0.01), cardiac fibrosis (−70%, P&lt;0.01), and cardiac dysfunction [cardiac index: 102±3 vs. 86±3 ml/min/kg, P&lt;0.05; left ventricular (LV) end-diastolic pressure: 12±2 vs. 20±2 mmHg, P&lt;0.05; LV dp/dtmin: 5856±259 vs. 4924±227 mmHg/sec, P&lt;0.05]. DT not only decreased serum levels of creatinine (0.54±0.02 vs. 0.63±0.03 mg/dl, P&lt;0.05) and uric acid (1.4±0.2 vs. 1.9±0.2 mg/dl, P&lt;0.05); but also decreased plasma levels of norepinephrine (273±38 vs. 846±242, P&lt;0.01), AVP (2729±347 vs. 4783±695 pg/ml, P&lt;0.05), BNP (360±13 vs. 460±39 pg/ml, P&lt;0.05), angiotensin II and aldosteron, and suppressed the systemic inflammation.

Conclusions

Donepezil treatment markedly prevented the progression of CHF and renal dysfunction, and improved the neurohumoral markers in the CHF rat model complicated with RAS-induced hypertension, suggesting that donepezil may be used as a new pharmacotherapy for CHF patients complicated with RAS-induced hypertension.

Funding Acknowledgement

Type of funding source: None

Donepezil as a novel therapy for suppressing the progression of cardiovascular remodeling in obesity-induced hypertensive rats with reperfused myocardial infarction

Introduction

Acetylcholinesterase inhibition by donepezil has been shown to improve long-term survival in permanent myocardial infarction (MI)-induced chronic heart failure rats. This study examined whether donepezil is applicable to the treatment of obesity-induced hypertension with reperfused MI (RMI).

Methods

Four-week-old SD rats were fed a high-fat diet (57% kcal as fat) for 15 weeks. We implanted a blood pressure (BP) telemetry into the animals (8-week-old) for monitoring artery pressure. After a 1-week recovery, RMI was created by occluding the left coronary artery (30min) followed by reperfusion. Surviving animals were randomly assigned to untreated (UT, n=16) or donepezil treated (DT, n=16, 3 mg/kg/day) group. After a 10-week treatment, the effects of donepezil were evaluated by hemodynamics, blood biomarkers, immunohistochemistry, and morphology.

Results

The high-fat diet caused obesity and hypertension (9-week-old: systolic BP = 134±4 mmHg; diastolic BP = 92±2 mmHg) in the normal rats. Compared with UT, DT significantly decreased the heart rate (296±5 vs. 318±8 bpm, P&lt;0.05). DT significantly prevented the progression of cardiac remodeling and dysfunction [cardiac index: 91±4 vs. 73±9 ml/min/kg, P&lt;0.01; left ventricular (LV) end-diastolic pressure: 11±1 vs. 20±2 mmHg, P&lt;0.01; LV dp/dt max: 5347±206 vs. 3637±433 mmHg/sec, P&lt;0.01], through increasing capillary density (+120%/field, P&lt;0.001), reducing cardiac fibrosis (−50%, P&lt;0.01) and myocardial infarcted area (17±2 vs. 24±2%, P&lt;0.05), suppressing cardiac hypertrophy (2.35±0.04 vs. 2.70±0.14 g/kg, P&lt;0.01) and coronary artery remodeling (wall thickness: 30±1 vs. 37±2 mm, P&lt;0.01; media-to-lumen ratio: 2.3±0.2 vs. 6.2±1.6, P&lt;0.001). Additionally, DT not only decreased plasma levels of insulin, norepinephrine, BNP, angiotensin II, but also improved the systemic inflammation.

Conclusions

Donepezil treatment significantly suppressed the progression of cardiovascular remodeling and dysfunction following RMI in obesity-induced hypertensive rats, suggesting that donepezil may be used as a potential candidate for post-RMI therapy in obesity-induced hypertensive patients.

Funding Acknowledgement

Type of funding source: None

TRAF5 promotes the occurrence and development of colon cancer via the activation of PI3K/AKT/NF-κB signaling pathways

This study aimed to investigate the expression and biological functions of TRAF5 in colon cancer at tissue and cellular levels. Forty-two patients with colon cancer were included in the present study. Tumor tissues and tumor-adjacent tissues were collected from all patients. Bioinformatics was used to analyze how TRAF5 was related to metastasis and prognosis of colon cancer. Quantitative real-time polymerase chain reaction was carried out to determine the expression of mRNA. SW620 and SW480 cells were used to study the inhibition and overexpression of TRAF5, respectively. CCK-8 assay was used to examine cell proliferation. Flow cytometry was employed to investigate cell phase and apoptosis. Transwell assay was used to study migration and invasion of cells. Western blotting was utilized to test how TRAF5 expression affected the activities of PI3K/AKT/NF-κB signaling pathways. Bioinformatics showed that the expression of TRAF5 in colon cancer tissues was correlated with metastasis and prognosis of the tumor. TRAF5 mRNA expression was up-regulated in colon cancer tissues, and related to recurrence and metastasis of the cancer. In vitro experiments showed that TRAF5 expression promoted proliferation, migration, and invasion of colon cancer cells, but reduced apoptosis of the cells. Moreover, TRAF5 might exert its biological functions by activating PI3K/AKT/NF-κB signaling pathways in colon cancer cells. In conclusion, TRAF5 expression in colon cancer tissues is up-regulated and correlated with prognosis, lymphatic metastasis and clinical staging. TRAF5 promotes the occurrence and development of colon cancer by activating PI3K/ AKT/NF-κB signaling pathways, and acts as an oncogene.

miR-940 promotes spinal cord injury recovery by inhibiting TLR4/NF-κB pathway-mediated inflammation

OBJECTIVE

The aim of this study was to investigate the effects of miR-940 and Toll-like receptor 4/Nuclear Factor κB (TLR4/NF-κB) pathways on inflammatory responses and spinal cord injury (SCI).

MATERIALS AND METHODS

This study first established a model of spinal cord injury in mice. The grip force measurement was used to detect the recovery of the forelimb, left forelimb and right forelimb of SCI mice. The quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to detect the expression of miR-940 and macrophage receptor TLR4 in SCI mice. In addition, the protein levels of TLR4 and inducible nitric oxide synthase (iNOS) in SCI mice were detected by Western blot. MiR-940 mimic was injected into the injured area of SCI mice to explore the effect of miR-940 overexpression on TLR4 and myeloperoxidase (MPO) expression as well as the protein levels of TLR4, P65 and iNOS. Furthermore, the grip strength of SCI mice with double forelimb, left forelimb and right forelimb was detected by the grip force test after miR-940 overexpression.

RESULTS

Compared with the sham-operated mice, the grip strength of the forelimb, left forelimb, and right forelimb of the SCI group showed significant obstacles. Meanwhile, the expression of miR-940 was remarkably decreased in SCI mice along with significant elevation of the inflammatory response-related factors including TRL4 and iNOS. Then we injected SCI mice with miR-940 mimics into the spinal cord injury area and found that miR-940 overexpression decreased the expression levels of TLR4 and MPO. At the same time, the overexpression of miR-940 markedly decreased the protein levels of TLR4, P65, and iNOS in SCI mice. In addition, miR-940 overexpression improved the grip strength of the left and right forepaws and the simultaneous grip strength of the two claws of the SCI mice than those of the simple injury group.

CONCLUSIONS

High expression of miR-940 can promote the recovery of spinal cord injury by downregulating the TLR4/NF-κB signaling pathway and inhibiting inflammation.

A nomogram based on a patient-reported outcomes measure: predicting the risk of readmission for patients with chronic heart failure

Background

Health-related quality of life, as evaluated by a patient-reported outcomes measure (PROM), is an important prognostic marker in patients with chronic heart failure. This study aimed to use PROM to establish an effective readmission nomogram for chronic heart failure.

Methods

Using a PROM as a measurement tool, we conducted a readmission nomogram for chronic heart failure on a prospective observational study comprising of 454 patients with chronic heart failure hospitalized between May 2017 to January 2020. A Concordance index and calibration curve were used to evaluate the discriminative ability and predictive accuracy of the nomogram. A bootstrap resampling method was used for internal validation of results.

Results

The median follow-up period in the study was 372 days. After a final COX regression analysis, the gender, income, health care, appetite-sleep, anxiety, depression, paranoia, support, and independence were identified and included in the nomogram. The nomogram showed moderate discrimination, with a concordance index of 0.737 (95% CI 0.673–0.800). The calibration curves for the probability of readmission for patients with chronic heart failure showed high consistency between the probability, as predicted, and the actual probability.

Conclusions

This model offers a platform to assess the risk of readmission for different populations with CHF and can assist clinicians with personalized treatment recommendations.

Resveratrol promotes mammary cell proliferation and antioxidation capacity during pregnancy and lactation in mice

AIMS

Reproduction can induce maternal oxidative stress, and resveratrol is able to alleviate oxidative stress. This study aimed to investigate the protective effects of resveratrol supplementation in mice during pregnancy and lactation.

METHODS AND RESULTS

Pregnant mice were randomly divided into three groups: (i) Pure water (Con); (ii) Cellulose sodium dissolves with 20 mg kg^-1 resveratrol (R1) and (iii) Cellulose sodium dissolves with 40 mg kg^-1 resveratrol (R2). The experiment starts at pregnancy and ends at weaning. The results showed that resveratrol increased mammary cell proliferation and the mRNA expressions of UDP glucuronosyltransferase family 1 member A1 (UGT1A1) and cytochrome P450 proteins (CYP1A1), while decreased superoxide dismutase, extracellular (SOD3) in the mammary gland. Further study showed that resveratrol promoted the mRNA expressions of genes involved in mitophagy, such as transcription factor Eβ (Tfeβ), Bcl1lc3β, homosapiens microtubule-associated protein 1 light-chain 3 beta (Map1lc3β), Parkin, sequestosome1 (p62), autophagy-related protein (Atg5) and Beclin-1 (Becn1) in the mammary gland. Moreover, resveratrol increased the abundances of some intestinal microbial species. 40 mg kg^-1 resveratrol significantly increased the contents of Acidobacteri, unidentified acidbacteria, Bacilales, Staphylococcaceae and Staphylococcus at phylum, class, order, family and genus level respectively.

CONCLUSION

Our results indicate that resveratrol supplementation may promote mammary cell proliferation and antioxidant ability through mitophagy and regulating gut microbiota in pregnant mice.

SIGNIFICANCE AND IMPACT OF THE STUDY

Current study proved that resveratrol could affect mammary cell proliferation and antioxidation capacity during pregnancy and lactation in mice for the first time. The underlying mechanisms may be related to mitophagy and gut microbiota.

MicroRNA-23c inhibits articular cartilage damage recovery by regulating MSCs differentiation to chondrocytes via reducing FGF2

OBJECTIVE

The aim of the study was to explore the role of microRNA-23c in the differentiation of marrow stromal cells (MSCs) to chondrocytes and its potential mechanism.

MATERIALS AND METHODS

MSCs were first isolated from rat bone marrow for cell culture. Surface antigens of MSCs (CD29 and CD34) were identified by flow cytometry. MSCs were induced for chondrogenic differentiation in MCDM (Mesenchymal Stem Cell Chondrogenic Differentiation Medium) for 0, 3, and 7 days, respectively, followed by detection of RUNX2, microRNA-23c and FGF2 expressions by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Alcian blue staining was performed to access proteoglycan deposition in MSCs transfected with microRNA-23c mimics or inhibitor. Western blot was conducted to detect the protein expressions of ACAN and COL2A1 in MSCs. The binding condition between microRNA-23c and FGF2 was verified by dual-luciferase reporter gene assay. Finally, MSCs were co-transfected with microRNA-23c mimics and FGF2 overexpression plasmid for rescue experiments.

RESULTS

On the fourth day of MSCs isolation, MSCs were in an elongated shape. Flow cytometry results showed positive expression of CD29 and negative expression of CD34, which were consistent with MSCs phenotype. QRT-PCR data elucidated that the mRNA levels of RUNX2 and FGF2 gradually increased, whereas microRNA-23c expression decreased with the prolongation of chondrogenic differentiation. Transfection of microRNA-23c mimics in MSCs remarkably elevated microRNA-23c expression. Alcian blue staining showed that microRNA-23c overexpression results in less proteoglycan deposition in MSCs than that of controls. Both mRNA and protein expressions of ACAN and COL2A1 decreased after microRNA-23c overexpression. Dual-luciferase reporter gene assay confirmed that FGF2 binds to microRNA-23c. Further Western blot results demonstrated that FGF2 expression is negatively regulated by microRNA-23c. FGF2 overexpression reversed the inhibitory effects of microRNA-23c on proteoglycan deposition, as well as expressions of ACAN and COL2A1.

CONCLUSIONS

MicroRNA-23c expression decreases during chondrogenic differentiation of MSCs, which inhibits MSCs differentiation to chondrocytes by inhibiting FGF2.

[Study on assessing early epidemiological parameters of COVID-19 epidemic in China]

Objective: To study the early dynamics of the epidemic of coronavirus disease (COVID-19) in China from 15 to 31 January, 2020, and estimate the corresponding epidemiological parameters (incubation period, generation interval and basic reproduction number) of the epidemic. Methods: By means of Weibull, Gamma and Lognormal distributions methods, we estimated the probability distribution of the incubation period and generation interval data obtained from the reported COVID-19 cases. Moreover, the AIC criterion was used to determine the optimal distribution. Considering the epidemic is ongoing, the exponential growth model was used to fit the incidence data of COVID-19 from 10 to 31 January, 2020, and exponential growth method, maximum likelihood method and SEIR model were used to estimate the basic reproduction number. Results: Early COVID-19 cases kept an increase in exponential growth manner before 26 January, 2020, then the increase trend became slower. The average incubation period was 5.01 (95%CI: 4.31-5.69) days; the average generation interval was 6.03 (95%CI: 5.20-6.91) days. The basic reproduction number was estimated to be 3.74 (95%CI: 3.63-3.87), 3.16 (95%CI: 2.90-3.43), and 3.91 (95%CI: 3.71-4.11) by three methods, respectively. Conclusions: The Gamma distribution fits both the generation interval and incubation period best, and the mean value of generation interval is 1.02 day longer than that of incubation period. The relatively high basic reproduction number indicates that the epidemic is still serious; Based on our analysis, the turning point of the epidemic would be seen on 26 January, the growth rate would be lower afterwards.

Beyond neurotransmission: acetylcholine in immunity and inflammation

Acetylcholine (ACh) is best known as a neurotransmitter and was the first such molecule identified. ACh signalling in the neuronal cholinergic system has long been known to regulate numerous biological processes (reviewed by Beckmann and Lips). In actuality, ACh is a ubiquitous signalling molecule that is produced by numerous non-neuronal cell types and even by some single-celled organisms. Within multicellular organisms, a non-neuronal cholinergic system that includes the immune system functions in parallel with the neuronal cholinergic system. Several immune cell types both respond to ACh signals and can directly produce ACh. Recent work from our laboratory has demonstrated that the capacity to produce ACh is an intrinsic property of T cells responding to viral infection, and that this ability to produce ACh is dependent upon IL-21 signalling to the T cells. Furthermore, during infection this immune-derived ACh is necessary for the T cells to migrate into infected tissues. In this review, we will discuss the various sources of ACh that are relevant during immune responses and describe how ACh acts on immune cells to influence their functions. We will also address the clinical implications of this fascinating aspect of immunity, focusing on ACh's role in the migration of T cells during infection and cancer.

Two groups of copperII pyridine–triazole complexes with “open or close” pepper rings and their in vitro antitumor activities

Based on 1,2-dimethoxyphenyl (veratrole, open) and 1,2-methylenedioxyphenyl (pepper ring, close)-derived pyridine–triazole analogues, two groups of copper(ii) complexes, namely, Group I(C1–C3) and Group II(C4–C6) were synthesized and fully characterized. All ligands and complexes were tested in vitro by MTT assays on seven tumour cell lines (T24, Hep-G2, Sk-Ov-3, MGC-803, HeLa, A549 and NCI-H460) and one normal liver cell line (HL-7702). Surprisingly, the pepper-ring-derived complexes (C4–C6) showed significantly enhanced cytotoxicity compared with the 1,2-bimethoxyphenyl ring-derived complexes (C1–C3) and the standard anticancer drug cisplatin. Cellular uptake assays indicated that the Cu accumulation was consistent with cytotoxicity. In addition, flow cytometry and western blot analysis showed that the apoptosis of the leading complex C4 may be induced by the Bcl-2 family-mediated proteins through the mitochondrial dysfunction pathway. Furthermore, UV-vis and fluorescence spectroscopy assays revealed that C4 has stronger insertion-binding interactions with CT-DNA than C1 and the fluorescence of C1 and C4 with BSA is mainly quenched by static quenching.

The pepper ring-modified complexes (Group II, C4–C6) exhibited significant antitumor activity than veratrole-modified complexes (Group I, C1–C3) towards several cancer cells with IC₅₀ ranging from 3.45 to 8.59 μM.

P105 Chronic vagal nerve stimulation suppress thirst through decreasing vasopressin secretion in the rats with chronic heart failure

Introduction

Chronic right cervical vagal nerve electric stimulation (VS) exerted prognostic benefits in heart failure rats. Exploring the mechanism is significant for clinical application. This study examined the effect of VS on arginine vasopressin (AVP) secretion and drinking behavior in the rats with chronic heart failure.

Methods

After a week recovery of myocardial infarction (MI), surviving rats after were randomly instrumented to VS group and sham stimulation (SS) group. A drop sensor was used to record real-time fluid consumption. Blood samples were collected weekly from the 3rd week during the 6 weeks treatment.

Results

Vagal stimulation did not change the daily fluid consumption (Mean ± SE, 76.2 ± 1.1 vs. 77.8 ± 2.1 ml/kg/day, n = 6, P &lt; 0.05). Thirst, which is defined as per drinking volume (PDV), significantly increased during the early weeks after MI (Fig A), while VS significantly suppressed PDV (Fig B is the data of 6th week) by increasing the drinking intervals. The level of plasma AVP was increased to about 2 fold during 6 weeks observation in the SS group, however, VS suppressed this upregulation (Fig C).

Conclusion

These results suggest that VS may activate vagal afferent components which related to inhibition of AVP secretion and then suppressed the augmentation of thirst. Frequent drinking small volume may benefit for homeostasis in CHF.

Abstract P105 Figure. Drinking behavior and AVP

Dietary leucine supplementation improves intestinal health of mice through intestinal SIgA secretion

AIMS

Leucine supplementation promotes intestinal health, but the mechanism is largely unknown. This study aimed to elucidate the mechanisms underlying the beneficial effects of leucine on intestinal homeostasis.

METHODS AND RESULTS

Female ICR mice (6-week-old) were randomly assigned into three groups: (i) mice received a basal diet; (ii) mice received a dietary 0·5% crystalline l-leucine supplementation; and (iii) mice received a dietary 1·0% crystalline l-leucine supplementation. Our results showed that leucine supplementation stimulated the secretion of SIgA in mice ileum and expression of cytokines related to SIgA production. Moreover, leucine supplementation improved the expression of mTOR and p70S6K1 expression. Further study showed that leucine supplementation markedly decreased microbiota richness and induced a shift in the Firmicutes : Bacteroidetes ratio in favour of Firmicutes.

CONCLUSIONS

Therefore, our data suggested that leucine supplementation could enhance intestinal health through the regulation of mTOR pathway and promoting SIgA secretion in the mouse intestine, which might be associated with intestinal microbiota.

SIGNIFICANCE AND IMPACT OF THE STUDY

The present study found that dietary leucine supplementation of mice could improve intestinal health by enhancing intestinal SIgA secretion via a nonexclusive mechanism, which might include T cell-dependent pathway, T cell-independent pathway and gut microbiota.

P3501Oral administration of donepezil markedly prevents the progression of chronic heart failure in renal artery stenosis-induced hypertensive rats

Introduction

Parasympathetic activation by donepezil has been shown to improve prognosis in chronic heart failure (CHF) rats following myocardial infarction. We examined whether donepezil is effective in the treatment of another CHF model complicated with renal artery stenosis (RAS)-induced hypertension.

Methods

RAS was created by ligating the left renal artery up to 50% in SD rats, at the same time, we implanted a blood pressure (BP) transmitter for confirming RAS-induced hypertension (7-week post-RAS: systolic BP = 154±7 mmHg; diastolic BP = 115±8 mmHg). At the 11th week after induction of RAS, surviving animals were randomly assigned to untreated (UT, n=10) or donepezil treated [DT, n=10, dissolved in drinking water (3mg/kg/day)] group. After a 6-week treatment, the effects of donepezil were evaluated by hemodynamics, blood levels of neurohumoral markers, and morphology.

Results

Compared with UT, DT significantly prevented the progression of the left kidney atrophy (2.38±0.13 vs. 1.51±0.34 g/kg, P<0.05). DT also significantly improved cardiac remodeling, through suppressing the progression of cardiac hypertrophy (2.30±0.06 vs. 2.57±0.08 g/kg, P<0.01), cardiac dysfunction [cardiac index: 102±3 vs. 86±3ml/min/kg, P<0.05; left ventricular (LV) end-diastolic pressure: 12±2 vs. 20±2 mmHg, P<0.05; LV dp/dtmin: 5856±259 vs. 4924±227 mmHg/sec, P<0.05]. DT not only decreased serum levels of creatinine (0.54±0.02 vs. 0.63±0.03 mg/dl, P<0.05) and uric acid (1.4±0.2 vs. 1.9±0.2 mg/dl, P<0.05); but also decreased plasma levels of norepinephrine (273±38 vs. 846±242, P<0.01), angiotensin II (17±2 vs. 23±2 pg/ml, P<0.05), AVP (2729±347 vs. 4783±695 pg/ml, P<0.05) and BNP (360±13 vs. 460±39 pg/ml, P<0.05), and suppressed the systemic inflammation (CRP: 190±12 vs. 382±58 mg/ml, P<0.01).

Conclusions

Donepezil treatment markedly prevented the progression of cardiac remodeling and renal dysfunction, and improved the neurohumoral markers in the CHF rat model complicated with RAS-induced hypertension, suggesting that donepezil may be used as a new pharmacotherapy for CHF patients complicated with RAS-induced hypertension.

P4605Landiolol, a beta-blocker, optimizes cardiac energetics and peripheral microhemodynamics better than ivabradine while reducing heart rate at hemodynamic resuscitation of experimental septic shock

Background

Septic shock is associated with sympathetic over-activation characterized by tachycardia, which is associated with poor survival. Though several kinds of drugs are available to reduce heart rate (HR), it is not clear which drug should be used to reduce HR effectively in initial hemodynamic resuscitation in septic shock.

Purpose

The aim of this study was to experimentally investigate comparative effects of landiolol (a β-blocker) and ivabradine (an If-channel inhibitor) on initial hemodynamic resuscitation in a canine model of endotoxin shock.

Methods

We used 19 anesthetized dogs. Seven dogs were allocated to control (CT) group, six dogs to landiolol (BB) group, and six dogs to ivabradine (IVA) group. In all the groups, endotoxin shock was induced by intravenous infusion of Escherichia coli lipopolysaccharide (4 mg/kg) over 1 h. After induction of endotoxin shock, we started hemodynamic resuscitation to restore mean arterial pressure (AP) and cardiac output (CO) by infusing noradrenaline (NA) and Ringer acetate solution (RiA). Dose of NA and RiA were automatically titrated with use of a computer-controlled drug infusion system that we developed previously. Hemodynamic resuscitation was continued for 4 h. During resuscitation, the BB group was given landiolol infusion at a low-dose range (1–10 μg/kg/min, manually titrated), while the IVA group was given ivabradine at 0.25 mg/kg bolus-injected every 2 h.

Results

The drug infusion system automatically restored AP to 70 mmHg and CO to greater than 90% of baseline level in all the groups. The restored AP and CO were not significantly different among the three groups (Figure A, B). There were no significant differences in the computer-controlled infusion rate of NA and cumulated volume of RiA infused among the three groups (Figure C). During the first 2 h of resuscitation, HR was significantly reduced in the BB and IVA groups in comparison to the CT group (Figure D). However, only in the BB group, cardiac oxygen consumption was significantly lower than that in the CT group (Figure E). Blood lactate level decreased significantly after hemodynamic resuscitation only within the BB group (Figure F).

Figure 1

Conclusions

In the initial hemodynamic resuscitation of septic shock, both low-dose landiolol infusion and ivabradine injection may be used to reduce HR. However, to optimize cardiac energetics and peripheral microhemodynamics, low-dose landiolol infusion may be preferable to ivabradine injection.

Acknowledgement/Funding

This work was supported by JSPS KAKENHI Grant Number 15K01307, 18K12126.

Billed and Paid Amounts for Preventive Procedures in Dental Medicaid

OBJECTIVE

To examine trends and variations in billed and paid amounts for preventive dental procedures by race/ethnicity, age, and sex in Wisconsin dental Medicaid.

METHODS

We analyzed data from the 2001 to 2013 Wisconsin Medicaid claims database for preventive dental procedures for children and adults. Billed and paid amounts for preventive dental procedures were aggregated over a visit and adjusted for inflation based on the Medical Care Consumer Price Index produced by the Bureau of Labor Statistics for 2013. Quantile regression was used to examine the trends over time and the effect of patient demographics.

RESULT

At the 50th and 75th percentiles, the overall billed amounts for preventive dental procedures were $84.97 and $105.53, and the paid amounts were $35.80 and $41.66, respectively. At the 75th percentile, there was a $2.24 increase per year in the billed amount and a $26.88 overall increase from 2001 to 2013. In the paid amount, there was a $1.34 decrease per year for an overall $16.07 decrease from 2001 to 2013. Billed and paid claims for racial/ethnic minority enrollees were $1 to $3 higher per visit at the 75th percentile when compared with those of Whites. Regarding the billed:paid ratio, White, African American, and Hispanic enrollees had values of 50% to 52%, whereas American Indians had the lowest value at 47.7%. At the 75th percentile, children aged 10 to 19 y had significantly higher billed ($26.73) and paid ($9.92) amounts than did adults aged 20 to 69 y.

CONCLUSION

The billed amount increased over time, and the paid amount decreased after adjustment for inflation. In addition, there was a wide gap between billed and paid amounts over time.

KNOWLEDGE TRANSFER STATEMENT

This study highlights clear differences between paid and billed amounts in Wisconsin dental Medicaid. The financial health of dental practices is dependent on appropriate reimbursement for dental services provided; thus, information of this nature could serve as a proxy performance measure for access to preventive dental care. Findings from this study could be used by policy makers and dental Medicaid program managers to develop outcome metrics to improve access to preventive dental services.

Sociodemographic Characteristics of Mission of Mercy Attendees in Wisconsin

OBJECTIVE

Mission of Mercy (MoM) events are scheduled to provide care to populations suffering from urgent needs and inadequate access to dental care in the United States. This study examined individual and county-level characteristics of MoM attendees and the factors associated with changes in the rate of attendance.

METHODS

Deidentified archival data for MoM events available from the America's Dentists Care Foundation (2013-2016) were analyzed. Summary statistics were calculated separately for each year. Chi-square test was performed to identify changes in attendance distribution over time. Poisson regression analyses were conducted to test changes in the rate of attendance with and without adjustment for county-level characteristics and history of prior MoM events.

RESULTS

Total numbers of attendees at Wisconsin MoM events were 1,560, 1,635, 1,187, and 951 in 2013, 2014, 2015, and 2016, respectively. Attendees were mostly female (>50%) and White (58%-81%), and mean age ranged between 36.5 and 39.2 y. The average travel distance ranged between 27 and 80 miles. Residents of counties where MoM events were held in previous years were more likely to attend another MoM event after adjusting for county distance to current location. After adjusting for dentists-to-population ratio, event history, and county distance to event location, we found that there was no statistically significant change in the rate of attendance from 2013 to 2016.

CONCLUSIONS

Previous attendees with experience of attending a MoM event in their counties of residence were more likely to attend another MoM event. Higher rates of attendance were associated with shorter travel distances to MoM events.

KNOWLEDGE TRANSFER STATEMENT

The Mission of Mercy (MoM) events are promoted by local dental organizations to highlight the issue of access to dental care and bring greater awareness to the problem by providing urgent dental care to populations in need. Through the data-sharing practices and analyses, policy makers, dental health advocates, and program organizers will have a better understanding of the impact and reach of the program. Findings from this study will help to expand program practices, promote efficiency, and aid in the identification of appropriate event locations, innovative strategies, and public policies relevant to addressing access to dental care.

Targeted TNF-α Overexpression Drives Salivary Gland Inflammation

Chronic inflammation of the salivary glands from pathologic conditions such as Sjögren's syndrome can result in glandular destruction and hyposalivation. To understand which molecular factors may play a role in clinical cases of salivary gland hypofunction, we developed an aquaporin 5 (AQP5) Cre mouse line to produce genetic recombination predominantly within the acinar cells of the glands. We then bred these mice with the TNF-αglo transgenic line to develop a mouse model with salivary gland-specific overexpression of TNF-α; which replicates conditions seen in sialadenitis, an inflammation of the salivary glands resulting from infection or autoimmune disorders such as Sjögren's syndrome. The resulting AQP5-Cre/TNF-αglo mice display severe inflammation in the salivary glands with acinar cell atrophy, fibrosis, and dilation of the ducts. AQP5 expression was reduced in the salivary glands, while tight junction integrity appeared to be disrupted. The immune dysregulation in the salivary gland of these mice led to hyposalivation and masticatory dysfunction.

Enhancement of fluorescence emission difference microscopy using conjugated vortex phase modulation

In this paper, we propose and demonstrate an improved fluorescence emission difference microscopy (FED) method, exploiting programmable phase modulation for image enhancement. The main novelty of the proposed approach lies in the matched size and intensity of two excitation spots. The proposed method improves the FED performance on image quality via artefact elimination. We demonstrate the feasibility of this method through theoretical studies and experimental tests. The experimental results of nanobeads and cells validate the practical performance of this method, which can enable reliable observations at superresolution in biomedical studies. LAY DESCRIPTION: In this paper, we propose a method to improve the imaging quality of regular fluorescence emission difference (FED) microscopy. In regular FED imaging, a solid and a doughnut excitation beam are successively used to acquire two images which are then subtracted with each other to improve the resolution of confocal microscopy. The doughnut beam can be generated by modulating the excitation beam with a vortex phase mask. Note that both of the excitation beam and the vortex phase mask must have the same handed direction in regular FED microscopy. However, some negative values may be produced and some information may be lost due to the subtraction process in regular FED imaging, which is mainly caused by the mismatched size and intensity of these two excitation spots. To address this issue, we propose conjugated FED (cFED) microscopy which additionally uses a conjugated vortex phase mask to modulate the solid beam to extend its focal spot size to be matched with the doughnut spot, which means the handed direction of the solid beam and the vortex phase mask is different. Besides, in order not to damage the resolution, the doughnut beam needs to be saturated to some degree. The experiment results show that, at the same resolution level, the negative values and the information loss in cFED image are all less than that of regular FED image.

Bimetallic cooperative effect on O–O bond formation: copper polypyridyl complexes as water oxidation catalyst

Two is better than one. The bimetallic cooperation in a binuclear copper complex, compared with the corresponding mononuclear catalyst, can decrease the catalytic overpotential and improve the catalytic efficiency.

Comparative Study for the Association of Mitochondrial Haplogroup F+ and Metabolic Syndrome between Longevity and Control Population in Guangxi Zhuang Autonomous Region, China

BACKGROUND

Our previous study suggested that mitochondrial haplogroup F (mtDNA F) was a longevity-associated biomarker, but the effect of mitochondrial haplogroup F on longevity individuals with metabolic syndrome (MetS) was not clear. Thus we explored the association between mtDNA F and MetS among longevity and control population in Guangxi Zhuang Autonomous Region, China.

METHOD

A total of 793 individuals consisting of 307 long-lived participants and 486 local healthy controls were involved in this study. Genotypes of mtDNA F were amplified by polymerase chain reaction and Sanger sequenced. MetS was defined according to the revised National Cholesterol Education Program's Adult Treatment Panel III (NCEP ATPIII ) criteria.

RESULTS

The prevalence of MetS in longevity group (28.0%) was higher than that (18.5%) in control group (P=0.002). Through the case-control stratify analysis, the prevalence of MetS in mtDNA F+ longevity individuals (29.8%) was 4.6 fold higher than that (5.3%) in local control group (P<0.001). However, after further longevity-only analysis, no association between MetS and mtDNA F+ in longevity group was observed (P=0.167). Following same analysis of two variables in control group, we found that the prevalence of MetS in mtDNA F- (95.8%) was higher than that in mtDNA F+ (5.3%); conversely, the prevalence of non-metabolic syndrome (NMetS) in mtDNA F+ (94.7%) was markedly higher than that in mtDNA F- (4.2%) (P<0.001).

CONCLUSION

We demonstrated that mtDNA F+ , as a molecuar biomarker, might not only confer beneficial effect to resistance against MetS but also function as a positive factor for long-life span among the population in Guangxi Zhuang Autonomous Region, China.