Interactions between sleep disturbances and Alzheimer's disease on brain function: a preliminary study combining the static and dynamic functional MRI

Though sleep disturbance constitutes the risk factor for Alzheimer's disease (AD), the underlying mechanism is still unclear. This study aims to explore the interaction between sleep disturbances and AD on brain function. We included 192 normal controls, 111 mild cognitive impairment (MCI), and 30 AD patients, with either poor or normal sleep (PS, NS, respectively). To explore the strength and stability of brain activity, we used static amplitude of low-frequency fluctuation (sALFF) and dynamic ALFF (dALFF) variance. Further, we examined white matter hyperintensities (WMH) and amyloid PET deposition, representing the vascular risk factor and AD-related hallmark, respectively. We observed that sleep disturbance significantly interacted with disease severity, exposing distinct effects on sALFF and dALFF variance. Interestingly, PS groups showed the dALFF variance trajectory of initially increased, then decreased and finally increased along the AD spectrum, while showing the opposite trajectory of sALFF. Further correlation analysis showed that the WMH burden correlates with dALFF variance in PS groups. Conclusively, our study suggested that sleep disturbance interacts with AD severity, expressing as effects of compensatory in MCI and de-compensatory in AD, respectively. Further, vascular impairment might act as important pathogenesis underlying the interaction effect between sleep and AD.

Observation of the Semileptonic D^{+} Decay into the K[over ¯]_{1}(1270)^{0} Axial-Vector Meson

By analyzing a 2.93  fb^{-1} data sample of e^{+}e^{-} collisions, recorded at a center-of-mass energy of 3.773 GeV with the BESIII detector operated at the BEPCII collider, we report the first observation of the semileptonic D^{+} transition into the axial-vector meson D^{+}→K[over ¯]_{1}(1270)^{0}e^{+}ν_{e} with a statistical significance greater than 10σ. Its decay branching fraction is determined to be B[D^{+}→K[over ¯]_{1}(1270)^{0}e^{+}ν_{e}]=(2.30±0.26_{-0.21}^{+0.18}±0.25)×10^{-3}, where the first and second uncertainties are statistical and systematic, respectively, and the third originates from the input branching fraction of K[over ¯]_{1}(1270)^{0}→K^{-}π^{+}π^{0}.

A Fuzzy-Based Risk Assessment Framework for Autonomous Underwater Vehicle Under-Ice Missions

The use of autonomous underwater vehicles (AUVs) for various scientific, commercial, and military applications has become more common with maturing technology and improved accessibility. One relatively new development lies in the use of AUVs for under-ice marine science research in the Antarctic. The extreme environment, ice cover, and inaccessibility as compared to open-water missions can result in a higher risk of loss. Therefore, having an effective assessment of risks before undertaking any Antarctic under-ice missions is crucial to ensure an AUV's survival. Existing risk assessment approaches predominantly focused on the use of historical fault log data of an AUV and elicitation of experts' opinions for probabilistic quantification. However, an AUV program in its early phases lacks historical data and any assessment of risk may be vague and ambiguous. In this article, a fuzzy-based risk assessment framework is proposed for quantifying the risk of AUV loss under ice. The framework uses the knowledge, prior experience of available subject matter experts, and the widely used semiquantitative risk assessment matrix, albeit in a new form. A well-developed example based on an upcoming mission by an ISE-explorer class AUV is presented to demonstrate the application and effectiveness of the proposed framework. The example demonstrates that the proposed fuzzy-based risk assessment framework is pragmatically useful for future under-ice AUV deployments. Sensitivity analysis demonstrates the validity of the proposed method.

Observation of the Leptonic Decay D^{+}→τ^{+}ν_{τ}

We report the first observation of D^{+}→τ^{+}ν_{τ} with a significance of 5.1σ. We measure B(D^{+}→τ^{+}ν_{τ})=(1.20±0.24_{stat}±0.12_{syst})×10^{-3}. Taking the world average B(D^{+}→μ^{+}ν_{μ})=(3.74±0.17)×10^{-4}, we obtain R_{τ/μ}=Γ(D^{+}→τ^{+}ν_{τ})/Γ(D^{+}→μ^{+}ν_{μ})=3.21±0.64_{stat}±0.43_{syst}., which is consistent with the standard model expectation of lepton flavor universality. Using external inputs, our results give values for the D^{+} decay constant f_{D^{+}} and the Cabibbo-Kobayashi-Maskawa matrix element |V_{cd}| that are consistent with, but less precise than, other determinations.

Doxapram alleviates low SpO2 induced by the combination of propofol and fentanyl during painless gastrointestinal endoscopy

BACKGROUND

Painless gastrointestinal endoscopy under intravenous propofol anesthesia is widely applied in the clinical scenario. Despite the good sedation and elimination of anxiety that propofol provides, low SpO2 may also result. Doxapram is a respiratory stimulant with a short half-life. The primary aim of this study was to investigate the effects of doxapram on alleviating low SpO2 induced by the combination of propofol and fentanyl during painless gastrointestinal endoscopy.

METHODS

In this prospective study, patients scheduled for painless gastrointestinal endoscopy were randomly assigned to group D or S with 55 patients per group. Initially, both groups received a combination of propofol and fentanyl. Patients in group D received 50 mg doxapram after propofol injection, while patients in group S received an equal volume of saline. Vital signs of the patients, propofol dose, examination duration, and incidences of low SpO2 were recorded.

RESULTS

There were no statistical differences in propofol consumption and examination duration between the two groups. Twenty-six patients in group S experienced low SpO2 versus 10 in group D (P = 0.001). Nineteen patients in group S underwent oxygenation with a face mask in contrast to 8 in group D (P = 0.015). Eighteen patients in group S were treated with jaw lifting compared to 5 in group D (P = 0.002). Four patients in group S underwent assisted respiration compared to 2 in group D (without statistical difference). The average oxygen saturation in group S was significantly lower than that in group D at 1, 2 and 3 min after propofol injection (P < 0.001, P = 0.001 and P = 0.020, respectively). There were no statistical differences in oxygen saturation at other time points. There were no statistical differences in MAP and HR (except for the time point of 1 min after the induction) between the two groups.

CONCLUSIONS

Low dose of doxapram can effectively alleviate low SpO2 in painless gastrointestinal endoscopy with intravenous propofol, without affecting propofol consumption, examination duration, MAP, or HR.

TRAIL REGISTRATION

The study was approved by the Institutional Ethics Committee of Clinical and New Technology of Wuxi People's Hospital on 20th July, 2018 (KYLLH2018029) and registered in the Chinese Clinical Trial Register on 16th August, 2018 (ChiCTR1800017832).

Bone marrow mesenchymal stem cells alleviate the daunorubicin-induced subacute myocardial injury in rats through inhibiting infiltration of T lymphocytes and antigen-presenting cells

INTRODUCTION

Bone marrow mesenchymal stem cells (BMSCs) have been extensively investigated from a perspective on cardiac regeneration therapy. The current study aimed to investigate the protective effect conferred by BMSCs in subacute myocardial injury, and to identify an appropriate BMSC reinfusion time.

METHODS

BMSCs were isolated from human bone marrow blood. Daunorubicin (DNR)-induced subacute myocardial models were subsequently established. The rats with DNR-induced subacute myocardial injury were injected with dexrazoxane (DZR) and/or BMSCs at varying time points, after which cardiac function was evaluated by assessing left ventricular ejection fraction (LVEF) and fraction shortening (FS). The myocardial structural changes were analyzed, after which the levels of CD3 and human leukocyte antigen DR (HLA-DR) were examined to further validate the mechanism by which BMSCs could influence subacute myocardial injury.

RESULTS

BMSCs combined with DZR treatment enhanced the cardiac function of rats with DNR-induced myocardial injury, as reflected by increased LVEF and FS. DNR-induced myocardial injuries were mitigated via the application of BMSCs combined with treatment of DZR, accompanied by diminished infiltration or vacuolization. Moreover, BMSCs were observed to alleviate infiltration of T lymphocyte and antigen-presenting cells, as evidenced by reduced expression of CD3 and HLA-DR.

CONCLUSION

Taken together, this study demonstrates that BMSCs could protect against DNR-induced myocardial injury, especially in the first three days of DNR administration. BMSCs combined with DZR exert a better therapeutic effect, but there are individual differences.

Evaluation the binding of chelerythrine, a potentially harmful toxin, with bovine serum albumin

Chelerythrine (CHE), a benzophenanthridine alkaloid, is usually used as a nutritional and functional additive in variety of health foods. However, it should be paid enough attention because of its potential toxicity to human health. In this work, the binding mechanism of CHE with bovine serum albumin (BSA) was systematically investigated with spectroscopic approaches. The results showed that the mixture of BSA with CHE could spontaneously cause the formation of BSA-CHE complex through electrostatic interaction under simulative physiological conditions (0.01 mol L^-1 Tris-HCl, 0.015 mol L^-1 NaCl, pH = 7.4). Site marker competitive displacement experiments exhibited that CHE was primarily bound to the hydrophobic pocket of the site II (subdomain IIIA) of BSA. It has been reported that the binding of small functional molecules to serum albumins remarkably impacts their absorption, distribution, metabolism, conformation, and excretion features. Therefore, this study might be helpful for human to have an in-depth understanding of the biological effect of CHE in vivo and guide human to take it safely and reasonably.

Lactate up-regulates the expression of PD-L1 in kidney and causes immunosuppression in septic Acute Renal Injury

BACKGROUND

This study aims to explore the mechanism of immunosuppression in septic Acute Renal Injury (AKI) and the role of programmed death-1 (PD-1/PD-L1) pathway in septic AKI.

METHODS

This study established a septic AKI model by Cecal ligation and puncture (CLP) in C57/B6 mice, ELISA was used to test the level of lactate and creatinine in serum, blood was collected for flow cytometry and kidney samples for Western blot analyses. This study further analyzed the expression of PD-L1 in kidney and the expression of PD-1 in CD4+, CD8+ T cell, and the number of CD3+ T cells to identify apoptosis in T cells in the blood.

RESULTS

The CLP sepsis model induced AKI in C57/B6 mice; The expression of PD-1 and PD-L1 were increased in septic AKI mice; PD-1/PD-L1 induced apoptosis in T cells: the number of lymphocytes decreased by 64%, while the number of CD3+ T cells decreased by 27% compared with the sham group; Results also indicated that lactate up-regulates expression of PD-L1 in the kidney.

CONCLUSIONS

Lactate activated PD-1/PD-L1 pathway can induce immunosuppression by inducing apoptosis in lymphocytes in septic AKI. Moreover, blocking the receptor of lactate or PD-1/PD-L1 might be a new therapy for septic AKI.

[Clinical characteristics and prognosis between male and female patients with premature coronary artery disease after intervention]

Objective: To compare the clinical characteristics and long-term prognosis between male and female patients with premature coronary artery disease (PCAD) post coronary intervention, and analyse the risk factors of major adverse cardio-cerebrovascular events (MACCE) and bleeding events. Methods: This was a prospective single-center observational study. From January 2013 to December 2013, 4 744 patients diagnosed as PCAD and treated with percutaneous coronary intervention (PCI) in Fuwai Hospital were enrolled. The general clinical data, laboratory results and interventional treatment data of all patients were collected, and patients were followed up for 2 years after PCI and the incidence of events including MACCE and bleeding was analyzed. The baseline data and clinical events of PCAD patients of different genders were compared. Survival curves were estimated by Kaplan-Meier method. Univariate and multivariate Cox regression were used to analyze whether gender was an influencing factor of different clinical events of PCAD patients within 2 years after PCI, and other relevant influencing factors of MACCE and bleeding events. Results: Among the 4 744 PCAD patients included, there were 3 390 (71.5%) male aged (47.0±5.4) years old and 1 354 (28.5%) female aged (57.0±5.8) years old. Compared with female patients, male patients had higher body mass index, higher proportion of hyperlipidemia, smoking, myocardial infarction, previous PCI, preoperative estimated glomerular filtration rate, ST-segment elevation myocardial infarction, radial artery approach, intravenous ultrasound use and chronic occlusive lesions (all P<0.05). Age, left ventricular ejection fraction, prevalence of hypertension, diabetes mellitus, past stroke history, non-ST-segment elevation acute coronary syndrome (NSTE-ACS) and the use of calcium channel blockers were lower in male patients than in female patients (all P<0.05). The 2-year follow-up results showed that the incidence of BARC type 1 hemorrhage was significantly higher in female patients than in male patients (6.9%(92/1 343) vs. 3.7%(126/3 378), P<0.001); however, the incidence of MACCE, all-cause death, cardiac death, recurrent myocardial infarction, revascularization (target vessel revascularization and target lesion revascularization), stent thrombosis, stroke and BARC type 2-5 hemorrhage were similar between the two groups (all P>0.05). Multivariate Cox regression analysis showed that gender was an independent risk factor for BARC type 1 bleeding in PCAD patients (HR=2.180, 95%CI 1.392-3.416, P<0.001), but it was not an independent risk factor for MACCE and BARC type 2-5 bleeding(all P>0.05). Hyperlipidemia, preoperative SYNTAX score, multivessel lesions and NSTE-ACS were the independent risk factors for MACCE in PCAD patients with PCI (the HRs(95%CI) were 1.289(1.052-1.580), 1.030(1.019-1.042), 1.758(1.365-2.264), 1.264(1.040-1.537), respectively); gender (HR=1.579, 95%CI 1.085-2.297, P=0.017), hyperlipidemia (HR=1.305, 95%CI 1.005-1.695, P=0.046), anticoagulant drugs including low molecular weight heparin (HR=1.321, 95%CI 1.002-1.741, P=0.048) or sulfonate(HR=1.659, 95%CI 1.198-2.298, P=0.002) were the independent risk factors for bleeding events. Conclusions: There are differences in clinical and coronary artery lesion characteristics between different genders in patients with PCAD. The incidence of minor bleeding is significantly higher in female PCAD patients than in male PCAD patients. Hyperlipidemia, preoperative SYNTAX score, multivessel lesions and NSTE-ACS are the independent risk factors for MACCE, and gender, hyperlipidemia, anticoagulant drugs including low molecular weight heparin or sulfonate are the independent risk factors for bleeding events in patients with PCAD.

Predictors of episodic migraine transformation to chronic migraine: A systematic review and meta-analysis of observational cohort studies

BACKGROUND AND PURPOSE

An estimated 2.5-3.1% of people with episodic migraine develop chronic migraine in a year. Several risk factors are associated with an increased risk for this transformation. We conducted a systematic review and meta-analysis to provide quantitative and qualitative data on predictors of this transformation.

METHODS

An electronic search was conducted for published, prospective, cohort studies that reported risk factors for chronic migraine among people with episodic migraine. Risk of bias was assessed using the Newcastle-Ottawa Quality Assessment Scale. Quality of evidence was determined according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidelines. Effect estimates were retrieved and summarized using risk ratios.

RESULTS

Of 5695 identified publications, 11 were eligible for inclusion. The pooled analysis (GRADE system) found "high" evidence for monthly headache day frequency ≥ 10 (risk ratio = 5.95), "moderate" evidence for depression (risk ratio = 1.58), monthly headache day frequency ≥ 5 (risk ratio = 3.18), and annual household income ≥ $50,000 (risk ratio = 0.65) and "very low" evidence for allodynia (risk ratio = 1.40) and medication overuse (risk ratio = 8.82) in predicting progression to chronic migraine.

CONCLUSIONS

High frequency episodic migraine and depression have high quality evidence as predictors of the transformation from episodic migraine to chronic migraine, while annual household income over $50,000 may be protective.

Serum Membrane Type 1-Matrix Metalloproteinase (MT1-MMP) mRNA Protected by Exosomes as a Potential Biomarker for Gastric Cancer

Background

Our previous research revealed that membrane type 1-matrix metalloproteinase (MT1-MMP) is overexpressed and plays a crucial role in gastric cancer (GC) progression. Exosomes are important for GC carcinogenesis, and the exosomal contents are ideal biomarkers. However, the expression of exosomal MT1-MMP mRNA in serum and its potential significance in GC remains unclear.

Material/Methods

The expression of exosomal MT1-MMP mRNA in serum of patients with GC, chronic gastritis, or atypical hyperplasia, and healthy controls was detected using real-time quantitative RT-PCR. Serum CEA, CA19-9, and CA72-4 were also measured by electrochemiluminescence assay.

Results

Exosomes were isolated and identified in serum, and serum exosomal MT1-MMP mRNA was found to be higher in patients with GC compared with healthy controls and patients with chronic gastritis or atypical hyperplasia (all P<0.05). Serum exosomal MT1-MMP mRNA was significantly correlated with tumor diameter, differentiation, Borrmann type, invasion depth, lymphatic metastasis, distal metastasis, and TNM stage. The AUC of exosomal MT1-MMP mRNA was 0.788 (95% CI: 0.714–0.850) with 63.9% sensitivity and 87.1% specificity, and was higher than that of CEA (0.655 (95% CI: 0.573–0.730)). The combination of 2 markers gave an AUC of 0.821 (95% CI: 0.750–0.878), which was better than with the individual marker. The sensitivity, specificity, and positive and negative predictive values were 75.6%, 83.9%, 94.7%, and 47.3%, respectively. Moreover, the multiple logistic regression model showed that tumor diameter, differentiation, invasion depth, and exosomal MT1-MMP mRNA were the risk factors for lymphatic metastasis in GC.

Conclusions

Our results characterized serum exosomal MT1-MMP mRNA in GC, providing a foundation for discovering serum exosomes-targeted biomarkers for GC diagnosis.

Characterization of the complete chloroplast genome of Sinosenecio oldhamianus (Compositae)

The complete chloroplast (cp) genome sequence of Sinosenecio oldhamianus, a common medicinal plant is widely distributed in South China. The plastome is 150,926 bp in length, with one large single-copy region of 94,588 bp, one small single-copy region of 18,130 bp, and two inverted repeat (IR) regions of 24,852 bp. It contains 134 genes, including 87 protein-coding genes, 8 ribosomal RNA, and 37 transfer RNA. The phylogenetic tree shows that this species is a sister to the genus Ligularia. The published plastome within Sinosenecio provides significant insight for elucidating the phylogenetic relationship of taxa within tribe Compositae.

In Vitro and In Vivo Study on the Effect of Lysosome-associated Protein Transmembrane 4 Beta on the Progression of Breast Cancer

Purpose

Although the effect of lysosome-associated protein transmembrane 4 beta (LAPTM4B) on the proliferation, migration, and invasion of breast cancer (BC) cells has already been studied, its specific role in BC progression is still elusive. Here, we evaluated the effect of different levels of LAPTM4B expression on the proliferation, invasion, adhesion, and tumor formation abilities of BC cells in vitro, as well as on breast tumor progression in vivo.

Methods

We investigated the influence of LAPTM4B expression on MCF-7 cell proliferation, invasion, adhesion, and tube formation abilities in vitro through its overexpression or knockdown and on breast tumor progression in vivo.

Results

Cell growth curves and colony formation assays showed that LAPTM4B promoted the proliferation of breast tumor cells. Cell cycle analysis results revealed that LAPTM4B promoted the entry of cells from the G1 into the S phase. Transwell invasion and cell extracellular matrix adhesion assays showed that LAPTM4B overexpression increased the invasion and adhesion capabilities of MCF-7 cells. More branches were observed in MCF-7 cells overexpressing LAPTM4B under an electron microscope. In comparison with LAPTM4B overexpression, LAPTM4B knockdown decreased the expression of vascular endothelial growth factor-A and significantly inhibited the vasculogenic tube formation ability of tumors. These results were also verified with western blot analysis.

Conclusion

LAPTM4B promoted the proliferation of MCF-7 cells through the downregulation of p21 (WAF1/CIP1) and caspase-3, and induced cell invasion, adhesion, and angiogenesis through the upregulation of hypoxia-inducible factor 1 alpha, matrix metalloproteinase 2 (MMP2), and MMP9 expression. This specific role deems LAPTM4B as a potential therapeutic target for BC treatment.

Computer-aided diagnosis of laryngeal cancer via deep learning based on laryngoscopic images

OBJECTIVE

To develop a deep convolutional neural network (DCNN) that can automatically detect laryngeal cancer (LCA) in laryngoscopic images.

METHODS

A DCNN-based diagnostic system was constructed and trained using 13,721 laryngoscopic images of LCA, precancerous laryngeal lesions (PRELCA), benign laryngeal tumors (BLT) and normal tissues (NORM) from 2 tertiary hospitals in China, including 2293 from 206 LCA subjects, 1807 from 203 PRELCA subjects, 6448 from 774 BLT subjects and 3191 from 633 NORM subjects. An independent test set of 1176 laryngoscopic images from other 3 tertiary hospitals in China, including 132 from 44 LCA subjects, 129 from 43 PRELCA subjects, 504 from 168 BLT subjects and 411 from 137 NORM subjects, was applied to the constructed DCNN to evaluate its performance against experienced endoscopists.

RESULTS

The DCCN achieved a sensitivity of 0.731, a specificity of 0.922, an AUC of 0.922, and the overall accuracy of 0.867 for detecting LCA and PRELCA among all lesions and normal tissues. When compared to human experts in an independent test set, the DCCN' s performance on detection of LCA and PRELCA achieved a sensitivity of 0.720, a specificity of 0.948, an AUC of 0.953, and the overall accuracy of 0.897, which was comparable to that of an experienced human expert with 10-20 years of work experience. Moreover, the overall accuracy of DCNN for detection of LCA was 0.773, which was also comparable to that of an experienced human expert with 10-20 years of work experience and exceeded the experts with less than 10 years of work experience.

CONCLUSIONS

The DCNN has high sensitivity and specificity for automated detection of LCA and PRELCA from BLT and NORM in laryngoscopic images. This novel and effective approach facilitates earlier diagnosis of early LCA, resulting in improved clinical outcomes and reducing the burden of endoscopists.

TCF-4 Regulated lncRNA-XIST Promotes M2 Polarization Of Macrophages And Is Associated With Lung Cancer

Background

Little is known about the biological function of long non-coding RNA X inactive specific transcript (lncRNA XIST) and its underlying mechanism in tumor-associated macrophage (TAM) polarization of lung cancer.

Materials and methods

The expression of lncRNA XIST in macrophages was detected by RT-qPCR. The function of lncRNA XIST on IL-4-induced M2 polarization was evaluated by transfection of shRNA and RT-qPCR or Western blotting detection of M2 specific markers. Contact between T-cell-specific transcription factor 4 (TCF-4) and lncRNA XIST was verified by bioinformatics and luciferase assay. The relation between lncRNA XIST and lung cancer was determined by bioinformatics.

Results

The expression of lncRNA XIST in THP-1-differentiated macrophages was significantly increased in M2 macrophages than M1 (P < 0.05). lncRNA XIST downregulation suppressed the IL-4-induced M2 polarization, inducing downregulation of M2 specific markers such as IL-10, Arg-1, and CD163. However, the suppression was aborted by overexpression of TCF-4. Mechanistically, lncRNA XIST was regulated by TCF-4 through direct binding. Additionally, lung cancer conditioned macrophages exhibited high expression of lncRNA XIST and lung cancer tissues highly expressed TCF-4, indicating TCF-4 regulated lncRNA XIST closely correlated with macrophage polarization and tumor progression of lung cancer.

Conclusion

Taken together, this study demonstrated the important role of TCF-4 regulated lncRNA XIST in regulating M2 polarization and gave a novel insight into the TAMs regulation and potential therapeutic target of lung cancer.

Injury Severity and Contributing Driver Actions in Passenger Vehicle-Truck Collisions

Large-scale truck-involved crashes attract great attention due to their increasingly severe injuries. The majority of those crashes are passenger vehicle–truck collisions. This study intends to investigate the critical relationship between truck/passenger vehicle driver’s intentional or unintentional actions and the associated injury severity in passenger vehicle–truck crashes. A random-parameter model was developed to estimate the complicated associations between the risk factors and injury severity by using a comprehensive Virginia crash dataset. The model explored the unobserved heterogeneity while controlling for the driver, vehicle, and roadway factors. Compared with truck passengers, occupants in passenger vehicles are six times and ten times more likely to suffer minor injuries and serious/fatal injuries, respectively. Importantly, regardless of whether passenger vehicle drivers undertook intentional or unintentional actions, the crashes are more likely to associate with more severe injury outcomes. In addition, crashes occurring late at night and in early mornings are often correlated with more severe injuries. Such associations between explanatory factors and injury severity are found to vary across the passenger vehicle–truck crashes, and such significant variations of estimated parameters further confirmed the validity of applying the random-parameter model. More implications based on the results and suggestions in terms of safe driving are discussed.

Complete Measurement of the Λ Electromagnetic Form Factors

The exclusive process e^{+}e^{-}→ΛΛ[over ¯], with Λ→pπ^{-} and Λ[over ¯]→p[over ¯]π^{+}, has been studied at sqrt[s]=2.396  GeV for measurement of the timelike Λ electric and magnetic form factors, G_{E} and G_{M}. A data sample, corresponding to an integrated luminosity of 66.9  pb^{-1}, was collected with the BESIII detector for this purpose. A multidimensional analysis with a complete decomposition of the spin structure of the reaction enables a determination of the modulus of the ratio R=|G_{E}/G_{M}| and, for the first time for any baryon, the relative phase ΔΦ=Φ_{E}-Φ_{M}. The resulting values are R=0.96±0.14(stat)±0.02(syst) and ΔΦ=37°±12°(stat)±6°(syst), respectively. These are obtained using the recently established and most precise value of the asymmetry parameter α_{Λ}=0.750±0.010 measured by BESIII. In addition, the cross section is measured with unprecedented precision to be σ=118.7±5.3(stat)±5.1(syst)  pb, which corresponds to an effective form factor of |G|=0.123±0.003(stat)±0.003(syst). The contribution from two-photon exchange is found to be negligible. Our result enables the first complete determination of baryon timelike electromagnetic form factors.

Amplitude Analysis of D_{s}^{+}→π^{+}π^{0}η and First Observation of the W-Annihilation Dominant Decays D_{s}^{+}→a_{0}(980)^{+}π^{0} and D_{s}^{+}→a_{0}(980)^{0}π^{+}

We present the first amplitude analysis of the decay D_{s}^{+}→π^{+}π^{0}η. We use an e^{+}e^{-} collision data sample corresponding to an integrated luminosity of 3.19  fb^{-1} collected with the BESIII detector at a center-of-mass energy of 4.178 GeV. We observe for the first time the W-annihilation dominant decays D_{s}^{+}→a_{0}(980)^{+}π^{0} and D_{s}^{+}→a_{0}(980)^{0}π^{+}. We measure the absolute branching fraction B(D_{s}^{+}→a_{0}(980)^{+(0)}π^{0^{(}+)},a_{0}(980)^{+(0)}→π^{+(0)}η)=(1.46±0.15_{stat}±0.23_{sys})%, which is larger than the branching fractions of other measured pure W-annihilation decays by at least one order of magnitude. In addition, we measure the branching fraction of D_{s}^{+}→π^{+}π^{0}η with significantly improved precision.

Application of T1-/T2-Weighted Ratio Mapping to Elucidate Intracortical Demyelination Process in the Alzheimer's Disease Continuum

Background The biological diagnosis criteria of the Alzheimer’s disease (AD) suggests that previous work may misclassify the cognitive impairment caused by other factors into AD. Consequently, re-assessing the imaging profile of AD continuum is needed. Considering the high vulnerability of cortical association fibers, we aimed to elucidate the cortical demyelination process in the AD continuum biologically defined.

Methods According to the biological diagnosis criteria, we determined the positive amyloid status (A+) as cerebrospinal fluid (CSF) amyloid_1–42 < 192 pg/ml, Florbetapir Positron emission tomography (PET) composite standardized uptake value ratio (SUVR) >1.11. Also, the positive Tau status (T+) was determined as p-Tau₁₈₁ > 23 pg/ml. Based on the cognitive characterization, we further categorized 252 subjects into 27 cognitively unimpaired with normal AD biomarkers (A−T−, controls), 49 preclinical AD (A+T+), 113 AD with mild cognitive impairment (MCI) (A+T+), and 63 AD dementia (A+T+). We estimated the intracortical myelin content used the T1- and T2-weighted (T1W/T2W) ratio mapping. To investigate the sensitivity of the ratio mapping, we also utilized well-validated AD imaging biomarkers as the reference, including gray matter volume and Fludeoxyglucose PET (FDG-PET). Based on the general linear model, we conducted the voxel-wise two-sample T-tests between the controls and each group in the AD continuum.

Results Compared to the controls, the results showed that the preclinical AD patients exhibited decreased T1W/T2W ratio value in the right inferior parietal lobule (IPL); as the disease progresses, the prodromal AD patients demonstrated lower ratio value in bilateral IPL, with hippocampus (HP) atrophy. Lastly, the AD dementia patients exhibited decreased ratio value in bilateral IPL and hippocampus; also, we observed the bilateral temporal cortices atrophy and widespread decreased metabolism in the AD dementia patients. After corrected with gray volume, the results remained mostly unchanged.

Conclusion Our study implied the decreased right IPL T1W/T2W ratio might represent early AD-related demyelination in disease continuum. Additionally, we demonstrated that the T1W/T2W ratio mapping is an easy-to-implement and sensitive metric to assess the intracortical myelin content in AD, particularly in the early stage.