A machine learning approach to investigate the materials science of enamel aging

Understanding aging of tooth tissues is critical to the development of patient-centric oral healthcare. Yet, the traditional methods for analyzing the composition-structure-property relationships of hard tissues have limitations when considering aging and other factors.

OBJECTIVE

To apply unsupervised machine learning tools to pursue an understanding of relationships between the composition and mechanical behavior of aging enamel.

METHODS

Molar teeth were collected from primary (age ≤ 8), young adult (24 ≤ age ≤ 46) and old adult (55 ≤ age) donors. The hardness and elastic modulus were quantified using nanoindentation as a function of distance from the Dentin Enamel Junction (DEJ) within the cervical, cuspal and inter-cuspal regions of the enamel crown. Similarly, a co-located analysis of the chemical composition and structure was performed using Raman spectroscopy. A Self-Organizing Maps (SOMs) algorithm was implemented to identify multi-dimensional composition-property relationships.

RESULTS

The hardness and elastic modulus are positively correlated to crystallinity and negatively correlated with carbonate substitution. Furthermore, the effects from fluoridation on the age-dependent properties of enamel is non-linear and depends on its location. The contributions of fluoridation to the enamel properties are different in the cervical and non-cervical regions and appear to be unique within primary and senior adult teeth.

SIGNIFICANCE

Based on the findings, unsupervised learning methods can reveal complicated non-linear structure-property relationships in tooth tissues and help to understand the materials science of aging and its consequences.

Measurements of the Branching Fractions of the Semileptonic Decays Ξ_{c}^{0}→Ξ^{-}ℓ^{+}ν_{ℓ} and the Asymmetry Parameter of Ξ_{c}^{0}→Ξ^{-}π^{+}

Using data samples of 89.5 and 711  fb^{-1} recorded at energies of sqrt[s]=10.52 and 10.58 GeV, respectively, with the Belle detector at the KEKB e^{+}e^{-} collider, we report measurements of branching fractions of semileptonic decays Ξ_{c}^{0}→Ξ^{-}ℓ^{+}ν_{ℓ} (ℓ=e or μ) and the CP-asymmetry parameter of Ξ_{c}^{0}→Ξ^{-}π^{+} decay. The branching fractions are measured to be B(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})=(1.31±0.04±0.07±0.38)% and B(Ξ_{c}^{0}→Ξ^{-}μ^{+}ν_{μ})=(1.27±0.06±0.10±0.37)%, and the decay parameter α_{Ξπ} is measured to be 0.63±0.03±0.01 with much improved precision compared with the current world average. The corresponding ratio B(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})/B(Ξ_{c}^{0}→Ξ^{-}μ^{+}ν_{μ}) is 1.03±0.05±0.07, which is consistent with the expectation of lepton flavor universality. The first measured asymmetry parameter A_{CP}=(α_{Ξ^{-}π^{+}}+α_{Ξ[over ¯]^{+}π^{-}})/(α_{Ξ^{-}π^{+}}-α_{Ξ[over ¯]^{+}π^{-}})=0.024±0.052±0.014 is found to be consistent with zero. The first and the second uncertainties above are statistical and systematic, respectively, while the third ones arise due to the uncertainty of the Ξ_{c}^{0}→Ξ^{-}π^{+} branching fraction.

[Endoscopic lateral neck dissection via the breast and transoral approaches for papillary thyroid carcinoma: a report of 10 cases]

Objective: To investigate the feasibility of endoscopic lateral neck dissection via the breast and transoral approaches (ELNDBTOA) for papillary thyroid carcinoma (PTC). Methods: From February 2015 to April 2019, 10 patients with PTC (cN1b) including 1 male and 9 females aged from 22 to 53 years old received ELNDBTOA in the General Surgery Department of Zhongshan Hospital, Xiamen University. Total thyroidectomy, the central lymph node dissection and the selective neck dissection (levels Ⅱ, Ⅲ and Ⅳ) were performed endoscopically via the breast approach, and then the residual lymph nodes were dissected via transoral approach. The medical records, operation time, blood loss, complications and postoperative follow-up outcomes were analyzed retrospectively. SPSS 22.0 software package was used for statistical processing of clinical data of patients. Results: All cases were successfully treated with ELNDBTOA without transfer to open surgery. The average operative time was (362.5±79.7) min, the blood loss was (23.0±14.9) ml, and the postoperative hospital stay was (5.1±1.3) days. The mean number of harvested cervical lymph nodes were (34.2±25.8), and the mean number of positive lymph nodes were (6.5±4.9). Lymph nodes were dissected by the further dissection via oral approach in 6 patients and a total of 9 lateral lymph nodes were havested from 2 of the 6 patients, with 3 positive lymph nodes. Two patients had transient skin numbness in the mandibular area and recovered within two weeks. One patient developed transient hypoparathyroidism and recovered within two months. No secondary bleeding, recurrent laryngeal nerve paralysis, chylous leakage, neck infection, permanent hypoparathyroidism or other complications were observed. The follow-up time was from 16 to 66 months with a median of 42.5 months, no tumor recurrence or metastasis occurred, and also no obvious deformity, abnormal sensation or movement in the chest, neck and mouth was observed. Conclusions: ELNBTOA is safe and feasible, with good cosmetic outcome.

Efficient hybrid method for the modal analysis of optical microcavities and nanoresonators

We propose a novel hybrid method for accurately and efficiently analyzing microcavities and nanoresonators. The method combines the marked spirit of quasinormal mode expansion approaches, e.g., analyticity and physical insight, with the renowned strengths of real-frequency simulations, e.g., accuracy and flexibility. Real- and complex-frequency simulations offer a complementarity between accuracy and computation speed, opening new perspectives for challenging inverse design of nanoresonators.

TDP-43 maintains chondrocyte homeostasis and alleviates cartilage degradation in osteoarthritis

OBJECTIVE

Osteoarthritis (OA) is the most prevalent age-related disorder due to cartilage degradation. Previous studies have identified aberrant chondrocyte homeostasis under extracellular stress as a key pathological mechanism behind cartilage degradation in OA. TDP-43, a DNA/RNA-binding protein has been demonstrated to participate in processing many extracellular stress responses; however, understanding of the role of TDP-43 in OA is limited. This study aims to investigate the role of TDP-43 in chondrocyte homeostasis and cartilage degradation in OA.

METHODS

The role of TDP-43 during degradation of cartilage is examined by experimental posttraumatic OA animal models and human cartilage specimens. Cartilage degradation is assessed by histological analysis, qPCR, and Western blot. The molecular mechanisms are investigated in vitro using human primary chondrocytes.

RESULTS

TDP-43 decreases significantly in degenerated cartilage. TDP-43 concentration is positively correlated with IL-1β concentration in synovial fluid derived from OA patients (Pearson r = 0.95, CI (95%) [0.80, 0.99], P < 0.0001). Intra-articular injection of recombinant TDP-43 significantly alleviates cartilage degradation and subchondral bone remodeling in vivo. In vitro mechanistic analyses show that TDP-43 maintains chondrocyte homeostasis under oxidative stress through regulating stress granule dynamics via G3BP1.

CONCLUSION

The present study indicates that TDP-43 maintains chondrocyte homeostasis under oxidative stress and alleviates cartilage degeneration in osteoarthritis, identifying TDP-43 as a potential target for the diagnosis and treatment of knee OA.

Publication trends and hotspots in enhanced recovery after surgery: 20-year bibliometric analysis

We evaluated enhanced recovery after surgery (ERAS) research and used bibliometric analysis to quantitatively and qualitatively predict research hotspots through extracting relevant publications from the core collection of the Web of Science database.

A233 AGING AND ESOPHAGEAL MOTILITY: A HIGH-RESOLUTION MANOMETRY STUDY

Background

Studies have found possible physiologic changes to esophageal motility with aging that are not currently taken into account in routine high-definition esophageal manometry (HDEM) interpretation.

Aims

We aimed to quantify the relationship between these physiologic changes and aging to improve HDEM interpretation.

Methods

We conducted a retrospective analysis of medical records for all patients who underwent HDEM at a tertiary hospital center between January 2015 and December 2019. Inclusion criteria were patients ≥18 years with normal HDEM. Exclusion criteria were abnormal HDEM; abnormal upper digestive endoscopy or imagery. Outcomes were median integrated relaxation pressure (IRP); mean lower esophageal sphincter (LES) pressure; mean distal contractal integral (DCI); mean distal latency (DL); mean peristaltic break (PB) according to the v3.0 Chicago classification criteria. Data was extracted from electronic patient medical records into a database for analysis. Effect of age on outcomes was examined through univariate and multivariate linear regression analysis.

Results

We identified 1917 patients with HDEM and included 790 patients with normal exams [mean age 55.8 yrs (IQR 46 – 66), 64% female]. Indications for HDEM included dysphagia (41.3%); gastroesophageal reflux disease (29.2%); chest pain (11.0%); other (13.3%). There was a statistically significant relationship between age and IRP [Coef=0.08 (95%CI 0.05 – 0.1), p&lt;0.001, R^2=0.04] as well as DCI [Coef=10.9 (95%CI 4.1 – 17.8), p=0.002, R^2=0.01] and DL [Coef=-0.01 (95%CI -0.02 – -0.002), p=0.01, R^2=0.008]. No statistically significant relationship was found between age and LES pressure [Coef=0.03 (95%CI -0.01 – 0.08), p=0.16] or PB [Coef=0.007 (95%CI -0.002 – 0.016), p=0.14]. Multivariate analysis showed statistically significant relationships between IRP and age (p&lt;0.001), BMI (p=0.001), NSAID use (p=0.034), and female sex (p=0.048).

Conclusions

We found that IRP, DCI, and DL are significantly correlated with the normal aging process. Modifications could therefore be considered for normal diagnostic cutoffs for both age extremes to prevent over or under-diagnosis of motility disorders.

Funding Agencies

None

[Analysis of the diagnotic results and complications of pneumoconiosis patients with different insurance types]

Objective: By comparing the diagnotic results and complications of pneumoconiosis patients with work-related injury insurance and non-work-related injury insurance, to provide reference for improving the medical insurance of pneumoconiosis patients. Methods: In May 2019, the diagnotic results and complications of 3204 patients with pneumoconiosis who were hospitalized in the second department of Hunan Prevention and Treatment Institute for Occupational Diseases from January 2017 to March 2019 were retrospectively analyzed. Results: Among the 3204 patients, 896 cases (28.0%) were in stage I, 790 cases (24.6%) were in stage II, and 1518 cases (47.4%) were in stage III. 1490 cases (46.5%) of pneumoconiosis patients have complications, mainly chronic obstructive pulmonary disease (COPD) (42.3%, 1354/3204) and lung infection (23.6%, 755/3204) . 584 cases (18.2%) were covered by work-related injury insurance, and the diagnosis of pneumoconiosis patients was mainly in the stage I (61.0%, 356/584) . 2620 cases (81.8%) were covered by non-work-related injury insurance, and the diagnosis of pneumoconiosis patients was mainly in the stage III (56.0%, 1466/2620) . The complication rate of non-work-related injury insurance patients (50.1%, 1312/2620) was higher than that of work-related injury insurance patients (30.5%, 178/584) (χ(2)=73.72, P<0.01) . Conclusion: The inpatients with pneumoconiosis in Hunan Province are still mainly covered by non-work-related injury insurance, and the diagnotic period and complication rate are significantly higher than those of work-related injury insurance patients. Therefore, pneumoconiosis patients should be provided with medical security, early diagnosis and early intervention, to prevent and delay the occurrence of complications.

Search for Axionlike Particles Produced in e^{+}e^{-} Collisions at Belle II

We present a search for the direct production of a light pseudoscalar a decaying into two photons with the Belle II detector at the SuperKEKB collider. We search for the process e^{+}e^{-}→γa, a→γγ in the mass range 0.2<m_{a}<9.7  GeV/c^{2} using data corresponding to an integrated luminosity of (445±3)  pb^{-1}. Light pseudoscalars interacting predominantly with standard model gauge bosons (so-called axionlike particles or ALPs) are frequently postulated in extensions of the standard model. We find no evidence for ALPs and set 95% confidence level upper limits on the coupling strength g_{aγγ} of ALPs to photons at the level of 10^{-3}  GeV^{-1}. The limits are the most restrictive to date for 0.2<m_{a}<1  GeV/c^{2}.

Search for an Invisibly Decaying Z^{'} Boson at Belle II in e^{+}e^{-}→μ^{+}μ^{-}(e^{±}μ^{∓}) Plus Missing Energy Final States

Theories beyond the standard model often predict the existence of an additional neutral boson, the Z^{'}. Using data collected by the Belle II experiment during 2018 at the SuperKEKB collider, we perform the first searches for the invisible decay of a Z^{'} in the process e^{+}e^{-}→μ^{+}μ^{-}Z^{'} and of a lepton-flavor-violating Z^{'} in e^{+}e^{-}→e^{±}μ^{∓}Z^{'}. We do not find any excess of events and set 90% credibility level upper limits on the cross sections of these processes. We translate the former, in the framework of an L_{μ}-L_{τ} theory, into upper limits on the Z^{'} coupling constant at the level of 5×10^{-2}-1 for M_{Z^{'}}≤6  GeV/c^{2}.

Long noncoding RNA LINC01510 is highly expressed in colorectal cancer and predicts favorable prognosis

OBJECTIVE

Long noncoding RNAs (lncRNAs) have recently emerged as important regulators in governing fundamental biological processes, as well as in tumorigenesis. LncRNA LINC01510 (LINC01510) was recently shown to be involved in colorectal cancer (CRC); however, its role in CRC remains unknown. The objective of this study was to evaluate LINC01510 expression and its relevance to the prognosis of CRC.

PATIENTS AND METHODS

LINC01510 expression was detected in CRC tissues and cell lines by using quantitative real-time PCR (qRT-PCR). The correction between LINC01510 expression and clinical characteristics was evaluated with x2-test. Survival curves and log-rank test were used to analyze patients' survival. A Cox proportional hazard model was constructed to evaluate the association of LINC01510 expression with overall survival and disease-free survival, respectively.

RESULTS

Here, we found that the levels of LINC01510 in CRC tissues were significantly higher than those in matched tumor-adjacent tissues. Moreover, high LINC01510 expression was observed to be closely correlated with histology/differentiation (p = 0.001), depth of invasion (p = 0.004) and TNM stage (p = 0.003). From the Kaplan-Meier survival curves, it was observed that patients with high expression of LINC01510 had shorter overall survival (p = 0.004) and disease-free survival (p = 0.000) as compared with the LINC01510-low group. In the multivariate analysis, high LINC01510 expression was an independent prognostic factor for both overall survival (p = 0.001) and disease-free survival (p = 0.001).

CONCLUSIONS

We demonstrated that low LINC01510 expression was associated with the progression of CRC and could serve as a potential independent prognostic biomarker for patients with CRC.

Grey matter changes in patients with vestibular migraine

AIM

To identify structural changes in the brain regions of patients with vestibular migraine (VM) so as to better understand its pathophysiology.

MATERIAL AND METHODS

The differences in grey matter (GM) in patients with VM, patients with migraine without aura (MWoA), and healthy controls (HC) were investigated. Using a GE Signa 3 T magnetic resonance imaging (MRI) system, 3D structural images were acquired from 18 VM, 21 MWoA, and 21 age-, gender-, and education level-matched HC using a T1-weighted magnetization-prepared rapid acquisition gradient-echo (MPRAGE) sequence. The volumetric abnormalities of GM were estimated by voxel-based morphometry. Analysis of variance and Bonferroni multiple comparisons were applied.

RESULTS

Compared with HC, patients with VM had significantly increased GM volume of the right medial superior frontal gyrus (p=0.008) and the right angular gyrus (p=0.009). Compared to patients with MWoA, patients with VM also had significantly increased volume of the right medial superior frontal gyrus (p=0.001), the right angular gyrus (p=0.008), and the left middle frontal gyrus (p=0.001).

CONCLUSIONS

The GM volume of some brain regions of patients with VM is significantly larger than the other two groups. The increased GM volume in these brain regions in patients with VM may be related to self-adaptation of the nervous system, leading to an abnormal brain sensitization. Some of the brain regions with increased GM volume identified in this study were involved in assessment, integration, and expectations of pain and were strongly related to mood and anxiety.

Diagnostic value of fecal B cell activating factor in patients with abdominal discomfort

Fecal calprotectin has successfully been widely recommended as a sensitive biomarker of inflammatory bowel diseases (IBD). Recently, we have identified an excellent new fecal biomarker, B cell activating factor (BAFF), as being as effective as fecal calprotectin for diagnosing intestinal inflammation. In this study, a total of 230 patients with abdominal discomfort were prospectively enrolled and fecal samples were collected within 24 h before the endoscopic examinations. We show that fecal BAFF levels were significantly higher in patients with ulcerative colitis (median = 1549 pg/g, P < 0·0001), Crohn's disease (median = 735 pg/g, P < 0·0001), gastric cancer (median = 267 pg/g, P < 0·0001) and colorectal cancer (median = 533 pg/g, P < 0·0001) than those in healthy groups (median = 61 pg/g), while the values of which in patients with gastric polyps, colorectal polyps, esophagitis/gastritis/duodenitis and peptic ulcer were in the range of healthy individuals (P > 0·05). An optimal cut-off value at 219·5 pg/g of fecal BAFF produced sensitivity, specificity, positive predictive and negative predictive values of 85, 91, 84 and 92%, respectively, for IBD or carcinoma. Our results therefore indicate a potential role for fecal BAFF as a sensitive screening parameter for IBD and gastrointestinal carcinoma, as well a useful tool to select patients with abdominal discomfort for further endoscopic examinations.

Shear-strain-mediated magnetoelectric effects revealed by imaging

Large changes in the magnetization of ferromagnetic films can be electrically driven by non-180° ferroelectric domain switching in underlying substrates, but the shear components of the strains that mediate these magnetoelectric effects have not been considered so far. Here we reveal the presence of these shear strains in a polycrystalline film of Ni on a 0.68Pb(Mg_1/3Nb_2/3)O₃-0.32PbTiO₃ substrate in the pseudo-cubic (011)_pc orientation. Although vibrating sample magnetometry records giant magnetoelectric effects that are consistent with the hitherto expected 90° rotations of a global magnetic easy axis, high-resolution vector maps of magnetization (constructed from photoemission electron microscopy data, with contrast from X-ray magnetic circular dichroism) reveal that the local magnetization typically rotates through smaller angles of 62-84°. This shortfall with respect to 90° is a consequence of the shear strain associated with ferroelectric domain switching. The non-orthogonality represents both a challenge and an opportunity for the development and miniaturization of magnetoelectric devices.