Construction and alidation of a severity prediction model for acute pancreatitis based on CT severity index: A retrospective case-control study.

To construct and internally and externally validate a nomogram model for predicting the severity of acute pancreatitis (AP) based on the CT severity index (CTSI).A retrospective analysis of clinical data from 200 AP patients diagnosed at the Hefei Third Clinical College of Anhui Medical University from June 2019 to June 2022 was conducted. Patients were classified into non-severe acute pancreatitis (NSAP, n = 135) and severe acute pancreatitis (SAP, n = 65) based on final clinical diagnosis. Differences in CTSI, general clinical features, and laboratory indicators between the two groups were compared. The LASSO regression model was used to select variables that might affect the severity of AP, and these variables were analyzed using multivariate logistic regression. A nomogram model was constructed using R software, and its AUC value was calculated. The accuracy and practicality of the model were evaluated using calibration curves, Hosmer-Lemeshow test, and decision curve analysis (DCA), with internal validation performed using the bootstrap method. Finally, 60 AP patients treated in the same hospital from July 2022 to December 2023 were selected for external validation.LASSO regression identified CTSI, BUN, D-D, NLR, and Ascites as five predictive factors. Unconditional binary logistic regression analysis showed that CTSI (OR = 2.141, 95%CI:1.369-3.504), BUN (OR = 1.378, 95%CI:1.026-1.959), NLR (OR = 1.370, 95%CI:1.016-1.906), D-D (OR = 1.500, 95%CI:1.112-2.110), and Ascites (OR = 5.517, 95%CI:1.217-2.993) were independent factors influencing SAP. The established prediction model had a C-index of 0.962, indicating high accuracy. Calibration curves demonstrated good consistency between predicted survival rates and actual survival rates. The C-indexes for internal and external validation were 0.935 and 0.901, respectively, with calibration curves close to the ideal line.The model based on CTSI and clinical indicators can effectively predict the severity of AP, providing a scientific basis for clinical decision-making by physicians.

Gradient gyroid Ti6Al4V scaffolds with TiO2 surface modification: Promising approach for large bone defect repair.

Large bone defects, particularly those exceeding the critical size, present a clinical challenge due to the limited regenerative capacity of bone tissue. Traditional treatments like autografts and allografts are constrained by donor availability, immune rejection, and mechanical performance. This study aimed to develop an effective solution by designing gradient gyroid scaffolds with titania (TiO2) surface modification for the repair of large segmental bone defects. The scaffolds were engineered to balance mechanical strength with the necessary internal space to promote new bone formation and nutrient exchange. A gradient design of the scaffold was optimized through Finite Element Analysis (FEA) and Computational Fluid Dynamics (CFD) simulations to enhance fluid flow and cell adhesion. In vivo studies in rabbits demonstrated that the G@TiO2 scaffold, featuring a gradient structure and TiO2 surface modification, exhibited superior healing capabilities compared to the homogeneous structure and TiO2 surface modification (H@TiO2) and gradient structure (G) scaffolds. At 12 weeks post-operation, in a bone defect representing nearly 30 % of the total length of the radius, the implantation of the G@TiO2 scaffold achieved a 27 % bone volume to tissue volume (BV/TV) ratio, demonstrating excellent osseointegration. The TiO2 surface modification provided photothermal antibacterial effects, enhancing the scaffold's biocompatibility and potential for infection prevention. These findings suggest that the gradient gyroid scaffold with TiO2 surface modification is a promising candidate for treating large segmental bone defects, offering a combination of mechanical strength, bioactivity, and infection resistance.

Novel anti-inflammatory diketopiperazine alkaloids from the marine-derived fungus Penicillium brasilianum.

Diketopiperazine alkaloids have proven the most abundant heterocyclic alkaloids up to now, which usually process diverse scaffolds and rich biological activities. In our search for bioactive diketopiperazine alkaloids from marine-derived fungi, two novel diketopiperazine alkaloids, penipiperazine A (1) and its biogenetically related new metabolite (2), together with a known analogue neofipiperzine C (3), were obtained from the strain Penicillium brasilianum. Their planar structures and absolute configurations were elucidated by extensive spectroscopic analyses, 13C NMR calculation, Marfey's, ECD, and ORD methods. Compound 1 featured a unique 6/5/6/6/5 indole-pyrazino-pyrazino-pyrrolo system, and its plausible biogenetic pathway was also proposed. Additionally, compounds 1-3 have been tested for their inflammatory activities. 1 and 2 significantly inhibited the release of NO and the expression of related pro-inflammatory cytokines on LPS-stimulated RAW264.7 cells, suggesting they could be attracting candidate for further development as anti-inflammatory agent. KEY POINTS: • A novel diketopiperazine alkaloid featuring a unique 6/5/6/6/5 indole-pyrazino-pyrazino-pyrrolo system was isolated from the marine fungus Penicillium brasilianum. • The structure of 1 was elucidated by detailed analysis of 2D NMR data, 13C NMR calculation, Marfey's, ECD, and ORD methods. • Compounds 1 and 2 significantly inhibited the release of NO and the expression of related pro-inflammatory cytokines on LPS-stimulated RAW264.7 cells.

[Research progress on brain functional near-infrared spectroscopy technology in the field of neonates]. / è„‘åŠŸèƒ½æ€§è¿‘çº¢å¤–å ‰è°±æŠ€æœ¯åœ¨æ–°ç”Ÿå„¿é¢†åŸŸä¸­çš„ç ”ç©¶è¿›å±•.

Functional near infrared spectroscopy (fNIRS) is an emerging neuroimaging tool that reflects the activity and function of brain neurons by monitoring changes in brain oxygen metabolism based on the neurovascular coupling mechanism. It is non-invasive and convenient, especially suitable for monitoring neonatal brain function. This article provides a comprehensive review of research related to the developmental patterns of brain networks concerning language, music, and emotions in neonates using fNIRS. It also covers brain network imaging in neonatal care, resting-state brain network connectivity patterns, and characteristics of brain functional imaging in disease states of neonates using fNIRS.

Arsenic exposure and lung function decline in chronic obstructive pulmonary disease patients: The mediating influence of systematic inflammation and oxidative stress.

Lung tissue is one of the target sites of arsenic (As). The goal of this investigation was to assess the associations of blood As concentration with pulmonary function indicators in patients with chronic obstructive pulmonary disease (COPD), as well as the roles of systemic inflammation and oxidative stress in this relationship. All 791 COPD patients were selected. Blood As concentration, and tumour necrosis factor-α (TNF-α) and 8-iso-prostaglandin-F2α (8-iso-PGF2α) were detected in the serum of COPD cases. Blood As was robustly related to pulmonary function parameters in an inverse dose-dependent manner. Multivariate linear regression analyses verified that a 1-unit increase of blood As was linked to declines of 0.263 L in FVC, 0.288 L in FEV1, 3.454 in FEV1/FVC%, and 0.538 in predicted FEV1%, respectively. The potential for pulmonary function decline gradually increased across the elevated tertiles of blood As. Nonsmokers were susceptible to As-induced pulmonary function reduction. Blood As was positively linked to the levels of TNF-α and 8-iso-PGF2α. Increased TNF-α and 8-iso-PGF2α partially mediated As-induced the reductions in FEV1 and FVC among COPD patients. As exposure is intensely linked to pulmonary function reduction. Systematic inflammation and oxidative stress partially mediate such associations in COPD patients.

( ±)-Dibrevianamides Q1 and Q2, the key precursors of asperginulin A from a marine-derived fungus.

Two pairs of new dimeric diketopiperazine alkaloids, ( ±)-dibrevianamides Q1 and Q2 (( ±)-1 and ( ±)-2), together with seven previously reported analogues (( ±)-3, 4-6, and ( ±)-7) were obtained from a marine-derived fungus Aspergillus sp. The structures of ( ±)-1 and ( ±)-2 were clarified using comprehensive spectroscopic analyses, the calculated ECD, and DP4 + probability methods. Speculated from the biogenesis, ( ±)-dibrevianamides Q1 and Q2 (( ±)-1 and ( ±)-2) might be the key precursor of [2 + 2] diketopiperazine dimers (( ±)-3). Compounds ( +)-1 and ( -)-2 displayed anti-H1N1 virus activity with IC50 values of 12.6 and 19.5 µM. Compound ( +)-1 showed significant activity against Mycobacterium tuberculosis (MIC, 10.2 µg/mL). KEY POINTS: • Two pairs of new dimeric diketopiperazine alkaloids were obtained from the marine-derived fungus Aspergillus sp. • The structures of the new compounds were clarified using comprehensive spectroscopic analyses, the calculated ECD, and DP4 + probability methods. • ( ±)-Dibrevianamides Q1 and Q2 were speculated to be the key precursor of [2 + 2] diketopiperazine dimers ( ±)-asperginulin A.

Structural diversity and biological activities of indole-diterpenoids from Penicillium janthinellum by co-culture with Paecilomyces formosus.

Co-culturing the marine-derived fungi Penicillium janthinellium with Paecilomyces formosus led to the isolation of nine new indole-diterpenes, janthinellumines A-I (1-9), along with twelve known analogues (10-21). The chemical structures including their absolute configurations of them were assigned by the analysis of extensive spectroscopic data and calculated ECD and VCD methods. These indole-diterpenoids displayed extensive biological activities, including anti-influenza A virus, protein tyrosine phosphatase (PTP) inhibitory, and anti-Vibrio activities. Among them, the anti-influenza mechanism of compounds 1, 2, and 7 was further investigated using neuraminidase inhibitory assay, molecular docking, and reverse genetics methods, suggesting that 1, 2, and 7 could interact with Arg371 of the viral neuraminidase. The structure-activity relationship (SAR) of PTPs inhibitory activity for indole-diterpene derivatives (1, 2, 4, 5, 9-16, and 19-21) was also summarized.

Glucose metabolism profile recorded by flash glucose monitoring system in patients with hypopituitarism during prednisone replacement.

BACKGROUND: Commonly used glucocorticoids replacement regimens in patients with hypopituitarism have difficulty mimicking physiological cortisol rhythms and are usually accompanied by risks of over-treatment, with adverse effects on glucose metabolism. Disorders associated with glucose metabolism are established risk factors of cardiovascular events, one of the life-threatening ramifications. AIM: To investigate the glycometabolism profile in patients with hypopituitarism receiving prednisone (Pred) replacement, and to clarify the impacts of different Pred doses on glycometabolism and consequent adverse cardiovascular outcomes. METHODS: Twenty patients with hypopituitarism receiving Pred replacement [patient group (PG)] and 20 normal controls (NCs) were recruited. A flash glucose monitoring system was used to record continuous glucose levels during the day, which provided information on glucose-target-rate, glucose variability (GV), period glucose level, and hypoglycemia occurrence at certain periods. Islet ß-cell function was also assessed. Based on the administered Pred dose per day, the PG was then regrouped into Pred > 5 mg/d and Pred ≤ 5 mg/d subgroups. Comparative analysis was carried out between the PG and NCs. RESULTS: Significantly altered glucose metabolism profiles were identified in the PG. This includes significant reductions in glucose-target-rate and nocturnal glucose level, along with elevations in GV, hypoglycemia occurrence and postprandial glucose level, when compared with those in NCs. Subgroup analysis indicated more significant glucose metabolism impairment in the Pred > 5 mg/d group, including significantly decreased glucose-target-rate and nocturnal glucose level, along with increased GV, hypoglycemia occurrence, and postprandial glucose level. With regard to islet ß-cell function, PG showed significant difference in homeostasis model assessment (HOMA)-ß compared with that of NCs; a notable difference in HOMA-ß was identified in Pred > 5 mg/d group when compared with those of NCs; as for Pred ≤ 5 mg/d group, significant differences were found in HOMA-ß, and fasting glucose/insulin ratio when compared with NCs. CONCLUSION: Our results demonstrated that Pred replacement disrupted glycometabolic homeostasis in patients with hypopituitarism. A Pred dose of > 5 mg/d seemed to cause more adverse effects on glycometabolism than a dose of ≤ 5 mg/d. Comprehensive and accurate evaluation is necessary to consider a suitable Pred replacement regimen, wherein, flash glucose monitoring system is a kind of promising and reliable assessment device. The present data allows us to thoroughly examine our modern treatment standards, especially in difficult cases such as hormonal replacement mimicking delicate natural cycles, in conditions such as diabetes mellitus that are rapidly growing in worldwide prevalence.

A Case of Sotos Syndrome in a Preterm Infant with Severe Bronchopulmonary Dysplasia and Congenital Heart Disease.

Sotos syndrome is an autosomal dominant genetic disorder caused by mutations in the NSD1 gene. In this study, we report a case of Sotos syndrome in a preterm infant. The main clinical manifestations were severe bronchopulmonary dysplasia, congenital heart disease, difficulty feeding, and characteristic facial appearance. The gene mutation was located at 177251854 on chromosome 5, and identified as a shear mutation, c.4765+1 G > A, which is a new mutation. The patient recovered well after symptomatic treatment. To the best of our knowledge, this is the first case of a preterm infant in whom a novel c.4765+1 G > A mutation in the NSD1 gene was identified. When premature infants present with abnormally severe bronchopulmonary dysplasia, feeding difficulties, and other congenital anomalies, Sotos syndrome should be considered.

Natural products from marine fungi as a source against agricultural pathogenic fungi.

There are many kinds of agricultural pathogenic fungi, which may belong to pathogenic fungi in different species, such as Fusarium, Alternaria, Colletotrichum, Phytophthora, and other agricultural pathogens. Pathogenic fungi from different sources are widely distributed in agriculture, which threaten the lives of crops around the world and caused great damage to agricultural production and economic benefits. Due to the particularity of the marine environment, marine-derived fungi could produce natural compounds with unique structures, rich diversities, and significant bioactivities. Since marine natural products with different structural characteristics could inhibit different kinds of agricultural pathogenic fungi, secondary metabolites with antifungal activity could be used as lead compounds against agricultural pathogenic fungi. In order to summarize the structural characteristics of marine natural products against agricultural pathogenic fungi, this review systematically overview the activities against agricultural pathogenic fungi of 198 secondary metabolites from different marine fungal sources. A total of 92 references published from 1998 to 2022 were cited. KEY POINTS: • Pathogenic fungi, which could cause damage to agriculture, were classified. • Structurally diverse antifungal compounds from marine-derived fungi were summarized. • The sources and distributions of these bioactive metabolites were analyzed.

Lever arm on bracket vs. lever arm on archwire: A 3D finite element method study of mechanics of miniscrew-supported lingual en-masse retraction of maxillary anterior teeth.

OBJECTIVE: To compare the deformation of the main archwire and 3D movements of maxillary anterior teeth during miniscrew-supported en-masse retraction with the lever arm on the archwire and on the brackets in lingual orthodontic treatment in finite element analysis (FEM) simulation. MATERIAL AND METHODS: A 3D dental-alveolar model with bonded 0.018×0.025-inch slot lingual brackets and a 0.017×0.025-inch dimension stainless-steel archwire was created. Four FEM models were created based on a 3D dental-alveolar model: in Models A and C, the lever arms were attached to the lingual bracket, while in Models B and D, the lever arms were attached to the archwire. Meanwhile, in Models A and B, the miniscrews were placed in between the molars, while in Models C and D, the miniscrews were positioned on the palatal roof. After a 1.5N retraction force was applied from the miniscrew to the end of the lever arm, the initial movements in the sagittal, transversal, and vertical planes were recorded and analysed for maxillary anterior teeth. RESULTS: In Models B and D, smaller deformation of the main archwire and less prominent bowing effect were noticed in both sagittal and vertical directions compared to their counter groups. In Models C and D, the central incisors showed less torque loss in the sagittal direction and more canine intrusion vertically. CONCLUSIONS: For the same lever arm-miniscrew retraction configuration, the lever arm on the bracket showed less deformation of the main archwire and more body movement of the teeth than the lever arm on the archwire group. With the same level arm height, the transverse and vertical bowing effect is reduced when the lever arm was placed distal to the central incisor and the miniscrews placed next to the palatal suture.

Cinchonine, a Potential Oral Small-Molecule Glucagon-Like Peptide-1 Receptor Agonist, Lowers Blood Glucose and Ameliorates Non-Alcoholic Steatohepatitis.

Purpose: The glucagon-like peptide-1 receptor (GLP-1R) is an effective therapeutic target for type 2 diabetes mellitus (T2DM) and non-alcoholic steatohepatitis (NASH). Research has focused on small-molecule GLP-1R agonists because of their ease of use in oral formulations and improved patient compliance. However, no small-molecule GLP-1R agonists are currently available in the market. We aimed to screen for a potential oral small-molecule GLP-1R agonist and evaluated its effect on blood glucose and NASH. Methods: The Connectivity map database was used to screen for candidate small-molecule compounds. Molecular docking was performed using SYBYL software. Rat pancreatic islets were incubated in different concentrations glucose solutions, with cinchonine or Exendin (9-39) added to determine insulin secretion levels. C57BL/6 mice, GLP-1R-/- mice and hGLP-1R mice were used to conduct oral glucose tolerance test. In addition, we fed ob/ob mice with the GAN diet to induce the NASH model. Cinchonine (50 mg/kg or 100 mg/kg) was administered orally twice daily to the mice. Serum liver enzymes were measured using biochemical analysis. Liver tissues were examined using Hematoxylin-eosin staining, Oil Red O staining and Sirius Red staining. Results: Based on the small intestinal transcriptome of geniposide, a recognized small-molecule GLP-1R agonist, we identified that cinchonine exerted GLP-1R agonist-like effects. Cinchonine had a good binding affinity for GLP-1R. Cinchonine promoted glucose-dependent insulin secretion, which could be attenuated significantly by Exendin (9-39), a specific GLP-1R antagonist. Moreover, cinchonine could reduce blood glucose in C57BL/6 and hGLP-1R mice, an effect that could be inhibited with GLP-1R knockout. In addition, cinchonine reduced body weight gain and food intake in ob/ob-GAN NASH mice dose-dependently. 100 mg/kg cinchonine significantly improved liver function by reducing the ALT, ALP and LDH levels. Importantly, 100 mg/kg cinchonine ameliorated hepatic steatosis and fibrosis in NASH mice. Conclusion: Cinchonine, a potential oral small-molecule GLP-1R agonist, could reduce blood glucose and ameliorate NASH, providing a strategy for developing small-molecule GLP-1R agonists.

3D printed PEKK bone analogs with internal porosity and surface modification for mandibular reconstruction: An in vivo rabbit model study.

Polyetheretherketone (PEEK) and its derivative polyetherketoneketone (PEKK) have been used as implant materials for spinal fusing and enjoyed their success for many years because of their mechanical properties similar to bone and their chemical inertness. The osseointegration of PEEKs is datable. Our strategy was to use custom-designed and 3D printed bone analogs with an optimized structure design and a modified PEKK surface to augment bone regeneration for mandibular reconstruction. Those bone analogs had internal porosities and a bioactive titanium oxide surface coating to promote osseointegration between native bone and PEKK analogs. Our workflow was 3D modeling, bone analog designing, structural optimization, mechanical analysis via finite element modeling, 3D printing of bone analogs and subsequently, an in vivo rabbit model study on mandibular reconstruction and histology evaluation. Our results showed the finite element analysis validated that the porous PEKK analogs provided a mechanical-sound structure for functional loadings. The bone analogs offered a perfect replacement for segmented bones in the terms of shape, form and volume for surgical reconstruction. The in vivo results showed that bioactive titanium oxide coating enhanced new bone in-growth into the porous PEKK analogs. We have validated our new approach in surgical mandibular reconstruction and we believe our strategy has a significant potential to improve mechanical and biological outcomes for patients who require mandibular reconstruction procedures.

Experimental validation of a new model for mandibular motions.

Long-term excessive forces loading from muscles of mastication during mandibular motions may result in disorders of temporomandibular joint (TMJ), myofascial pain, and restriction of jaw opening and closing. Current analysis of mandibular movements is generally conducted with a single opening, protrusive and lateral movements rather than composite motions that the three can be combined arbitrarily. The objective of this study was to construct theoretical equations reflecting the correlation between composite motions and muscle forces, and consequently to analyze the mandibular composite motions and the tensions of muscles of mastication in multiple dimensions. The muscle performances such as strength, power, and endurance of mandibular motions were analyzed and the effective motion range of each muscle was derived. The mandibular composite motion model was simplified by calculating muscle forces. An orthogonal rotation matrix based on muscle forces was established. A 3D printed mandible was used for in vitro simulation of mandibular motions on a robot and measurements of force were conducted. The theoretical model and forces were verified through a trajectory tracing experiment of mandibular motions driven by a 6-axis robot with force/torque sensors. Through the analysis of the mandibular composite motion model, the motion form was obtained and transferred to guide the motions of the robot. The error between the experimental data obtained by the 6-axis force/torque sensors and the theoretical data was within 0.6 N. Our system provides excellent visualization for analyzing the changes of muscle forces and locations during various mandibular movements. It is useful for clinicians to diagnose and formulate treatment for patients who suffer from (temporomandibular joint disorders) TMDs and restrict jaw movements. The system can potentially offer the comparison before and after treatment of TMDs or jaw surgery.

Short-term acute bright light exposure induces a prolonged anxiogenic effect in mice via a retinal ipRGC-CeA circuit.

Light modulates mood through various retina-brain pathways. We showed that mice treated with short-term acute bright light exposure displayed anxiety-related phenotypes in a prolonged manner even after the termination of the exposure. Such a postexposure anxiogenic effect depended upon melanopsin-based intrinsically photosensitive retinal ganglion cell (ipRGC) activities rather than rod/cone photoreceptor inputs. Chemogenetic manipulation of specific central nuclei demonstrated that the ipRGC-central amygdala (CeA) visual circuit played a key role in this effect. The corticosterone system was likely to be involved in this effect, as evidenced by enhanced expression of the glucocorticoid receptor (GR) protein in the CeA and the bed nucleus of the stria terminalis and by the absence of this effect in animals treated with the GR antagonist. Together, our findings reveal a non-image forming visual circuit specifically designed for "the delayed" extinction of anxiety against potential threats, thus conferring a survival advantage.

[Effects of Continuous Straw Returning with Chemical Fertilizer on the Carbon Pool and Crop Yield of Rice-Rape Rotation Soils].

According to the positioning experiment of straw returning in the continuous field 7a, the effects of straw returning combined with chemical fertilizer on soil total organic carbon (TOC), dissolved organic carbon (DOC), particulate organic carbon (POC), labile organic carbon (LOC), carbon pool management index (CPMI), and crop yield in farmland soil profiles (0-20, 20-50, and 50-80 cm) in the Chaohu Lake area were studied. There were four treatments:no straw returning+no fertilization (CK), conventional fertilization (F), straw returning+conventional fertilization (SF1), and straw returning+80% conventional fertilization (SF2). The changes in soil total organic carbon and component content, CPMI, and rape rice yield in different soil layers were analyzed. Taking CK as a reference, conventional fertilization and straw returning combined with chemical fertilizer increased the content of total organic carbon and components in the soil vertical profile, and the content of total organic carbon and components in different soil layers decreased gradually with the increase in soil depth. In the 0-20 cm soil layer, compared with that in the F treatment, the SF1 and SF2 treatments significantly increased the contents of TOC, DOC, POC, and LOC by 14.23%-28.97%, 7.86%-27.01%, 16.46%-24.24%, and 5.89%-6.64%, respectively (P<0.05). In the 20-50 cm soil layer, the contents of TOC and LOC in SF1 were significantly increased by 9.43% and 8.34%, respectively, compared with those in the F treatment (P<0.05), and the contents of DOC and POC in SF2 were significantly increased by 17.51% and 65.83% compared with those in the F treatment (P<0.05). In the 50-80 cm soil layer, there was no significant difference in the contents of total organic carbon and components among the treatments. The effect of straw returning and chemical fertilizer on the soil carbon pool management index was significant. SF1 significantly improved the CPMI of the 0-50 cm soil layer compared with that in the F treatment, whereas the CPMI of the F treatment was the largest in the 50-80 cm soil layer; however, there was no significant difference among all treatments. Straw returning combined with chemical fertilizer had a significant effect on crop yield, and the yield of the SF1 treatment was the highest; compared with that of the F treatment, the rice, rape, and annual yields were significantly increased by 6.19%, 7.67%, and 6.54%, respectively (P<0.05). In general, straw returning combined with chemical fertilizer was of great significance to improve the soil carbon pool, soil fertility, and crop yield in the Chaohu Lake area.

Effect of the prosthetic index on stress distribution in Morse taper connection implant system and peri-implant bone: a 3D finite element analysis.

BACKGROUND: The combination of a prosthetic index with Morse taper connection was developed, with the purpose of making prosthetic procedures more precise. However, the presence of the index may compromise the mechanical performance of the abutment. The aim of this study is to evaluate the effect of prosthetic index on stress distribution in implant-abutment-screw system and peri-implant bone by using the 3D finite element methodology. METHODS: Two commercial dental implant systems with different implant-abutment connections were used: the Morse taper connection with platform switching (MT-PS) implant system and the internal hex connection with platform matching (IH-PM) implant system. Meanwhile, there are two different designs of Morse taper connection abutment, namely, abutments with or without index. Consequently, three different models were developed and evaluated: (1) MT-PS indexed, (2) MT-PS non-indexed, and (3) IH-PM. These models were inserted into a bone block. Vertical and oblique forces of 100 N were applied to each abutment to simulate occlusal loadings. RESULTS: For the MT-PS implant system, the maximum stress was always concentrated in the abutment neck under both vertical and oblique loading. Moreover, the maximum von Mises stress in the neck of the MT-PS abutment with index even exceed the yield strength of titanium alloy under the oblique loading. For the IH-PM implant system, however, the maximum stress was always located at the implant. Additionally, the MT-PS implant system has a significantly higher stress level in the abutment neck and a lower stress level around the peri-implant bone compared to the IH-PM implant system. The combined average maximum stress from vertical and oblique loads is 2.04 times higher in the MT-PS indexed model, and 1.82 times for the MT-PS non-indexed model than that of the IH-PM model. CONCLUSIONS: MT-PS with index will cause higher stress concentration on the abutment neck than that of without index, which is more prone to mechanical complications. Nevertheless, MT-PS decreases stress within cancellous bone and may contribute to limiting crestal bone resorption.

Reference Values for Point-of-Care Echocardiographic Measurements of Preterm Infants in China.

Background: Few studies have examined the reference value of the left ventricular structure and function in preterm infants. This study was designed to establish a point-of-care echocardiographic reference range of left ventricular structure and function based on different gestational age, weight, and body surface area (BSA) for preterm infants within 7 days after birth. Methods: We retrospectively studied 489 patients with traditional echocardiographic data of left ventricular (LV) M-mode: LV end diastolic dimensions (LVED), LV end systolic dimension (LVES), end-diastolic interventricular septal thickness (IVSd), end diastolic LV posterior wall thickness (LVPWd), left atrial (LA) and aortic root (AO) diameters, and index of LA/AO, LV ejection fraction (LVEF), LV fractional shortening (LVFS), and pulsed wave Doppler: aortic valve flow rate (AV), peak mitral valve flow rate E(MV-E), peak mitral valve flow rate A(MV-A), and MV-E/A. The LV dimensions and the maximum blood flow velocities of the aortic valves and mitral valves according to gestational age, birth weight, and body surface area (BSA) are presented in percentiles tables. Percentile curves of aforesaid four cardiac measurements (LVED, LA diameter (LAD), MV-E, MV-E/A) using the R language Generalized Additive Models for Location, Scale and Shape (GAMLSS) method were developed according to different gestational ages and weights. Results: Measurements of all cardiac dimensions and Doppler maximum velocities of AV, MV-E, and MV-E/A showed a correlation with gestational age, weight, and BSA. LVED, LAD, MV-E, and MV-E/A showed a trend of increasing values with gestational age and weight on the percentile curves. Conclusion: The percentile tables and graphs of these point-of-care echocardiographic data can provide reliable reference data for Chinese neonates. Normative values are recommended as a source of reference data for the identification of potentially abnormal echocardiography.

The role of ipRGCs in ocular growth and myopia development.

The increasing global prevalence of myopia calls for elaboration of the pathogenesis of this disease. Here, we show that selective ablation and activation of intrinsically photosensitive retinal ganglion cells (ipRGCs) in developing mice induced myopic and hyperopic refractive shifts by modulating the corneal radius of curvature (CRC) and axial length (AL) in an opposite way. Melanopsin- and rod/cone-driven signals of ipRGCs were found to influence refractive development by affecting the AL and CRC, respectively. The role of ipRGCs in myopia progression is evidenced by attenuated form-deprivation myopia magnitudes in ipRGC-ablated and melanopsin-deficient animals and by enhanced melanopsin expression/photoresponses in form-deprived eyes. Cell subtype-specific ablation showed that M1 subtype cells, and probably M2/M3 subtype cells, are involved in ocular development. Thus, ipRGCs contribute substantially to mouse eye growth and myopia development, which may inspire novel strategies for myopia intervention.

3D-printed porous condylar prosthesis for temporomandibular joint replacement: Design and biomechanical analysis.

BACKGROUND: Customized prosthetic joint replacements have crucial applications in severe temporomandibular joint problems, and the combined use of porous titanium scaffold is a potential method to rehabilitate the patients. OBJECTIVE: The objective of the study was to develop a design method to obtain a titanium alloy porous condylar prosthesis with good function and esthetic outcomes for mandibular reconstruction. METHODS: A 3D virtual mandibular model was created from CBCT data. A condylar defect model was subsequently created by virtual condylectomy on the initial mandibular model. The segmented condylar defect model was reconstructed by either solid or porous condyle with a fixation plate. The porous condyle was created by a density-driven modeling scheme with an inhomogeneous tetrahedral lattice structure. The porous condyle, supporting fixation plate, and screw locations were topologically optimized. Biomechanical behaviors of porous and solid condylar prostheses made of Ti-6Al-4V alloy were compared. Finite element analysis (FEA) was used to evaluate maximum stress distribution on both prostheses and the remaining mandibular ramus. RESULTS: The FEA results showed levels of maximum stresses were 6.6%, 36.4% and 47.8% less for the porous model compared to the solid model for LCI, LRM, and LBM loading conditions. Compared to the solid prosthesis, the porous prosthesis had a weight reduction of 57.7% and the volume of porosity of the porous condyle was 65% after the topological optimization process. CONCLUSIONS: A custom-made porous condylar prosthesis with fixation plate was designed in this study. The 3D printed Ti-6Al-4V porous condylar prosthesis had reduced weight and effective modulus of elasticity close to that of cortical bone. The.