Gentianine alleviates dextran sulfate sodium-induced ulcerative colitis via inhibition of TLR4/NLRP3-mediated pyroptosis.

OBJECTIVES: Ulcerative colitis (UC) is a common inflammatory bowel disorder. Gentiana scabra Bunge is a traditional medicinal plant that is used to treat a variety of diseases. Studies have shown that gentianine (GTN) from Gentiana scabra inhibits the development of inflammatory diseases. The purpose of this study was to investigate the effect and possible mechanism of action of GTN on UC in mice. METHODS: An animal model of UC was established using dextran sulfate sodium (DSS). Mice were administered intraperitoneally with GTN (12.5, 25, or 50 mg/kg/day) for seven days. Body weight and disease activity index (DAI) were monitored daily during GTN administration. Colon length, pathological changes, and myeloperoxidase (MPO) activity were measured following GTN administration. The signalling pathways regulated by GTN were analysed using machine learning. HT-29 cells were used to verify the effect and mechanism of action of GTN on UC in vitro. RESULTS: GTN suppressed weight loss, shortened colon length, alleviated colon injury, and reduced the DAI score and MPO activity of mice with UC in a dose-dependent manner. Further analysis showed that GTN inhibited the NOD-like receptor (NLR) signalling pathway. GTN markedly decreased the levels of NLR signalling pathway-related proteins. Moreover, GTN decreased the levels of pyroptosis-related proteins, IL-1ß and IL-18. The in vitro data were consistent with those of animal experiments. Furthermore, TLR4 and NLRP3 overexpression eliminated the protective effects of GTN in HT-29 cells. CONCLUSION: Gentianine alleviated DSS-induced UC by inhibiting TLR4/NLRP3-mediated pyroptosis.

Rim plate in the treatment of hyperextension tibial plateau fracture: surgical technique and a series of cases.

BACKGROUND: The existence of a "bare area" at the anterior plateau has been observed in cases where anteromedial and/or anterolateral proximal tibial locking plates are used for fixation in the treatment of hyperextension tibial plateau fractures (HTPF). The objective of this study is to introduce the rim plate fixation technique and evaluate its clinical efficacy. METHODS: A retrospective analysis was conducted on HTPF patients who underwent treatment with a combination of rim plate and proximal tibial locking plate at our hospital between April 2015 and December 2019. All patients were followed up for a minimum of one year. Open reduction and internal fixation were performed using anteromedial/posteromedial and/or anterolateral approaches for all cases. The surgical strategies employed for rim plate fixation were introduced, and both radiographic and clinical outcomes were assessed. RESULTS: Thirteen patients were enrolled in the study, with an average follow-up time of 4.3 years. Satisfactory reduction was achieved and radiographically maintained in all cases. Additionally, all patients exhibited satisfactory clinical functions, as evidenced by a mean hospital for special surgery (HSS) knee score of 96.2 ± 2.0 (range: 90-98). Furthermore, no wound complications or implant breakage were observed in this series. CONCLUSION: The combination of the rim plate and proximal tibial plate proved to be an effective fixation configuration, resulting in satisfactory clinical outcomes.

Areal measurement of vibration modes of a hemispherical shell resonator by deflectometry.

The hemispherical shell resonator (HSR) is the core and sensitive part of a hemispherical resonator gyro. The geometrical accuracy and vibration properties of HSR determine the navigation performance of the system. A lack of areal measurement methods of vibration modes limits investigation of the kinetic mechanism and improvement in navigation performance. Consequently, an areal measurement method is developed based on deflectometry. The blurry spots on the image plane reflected from the vibrating HSR are extracted, and the blurring trajectories are obtained by the Wiener deconvolution method. The vibrating amplitude distribution of a standing wave mode is transformed into the swing angle distribution of normal vectors. The parameters of the vibration mode are fitted by the Levenberg-Marquardt method. This method can find widespread applications in the areal inspection of vibration modes.

The Effects of COVID-19 on Geriatric Hip Fracture Management and 1-Year Mortality in Beijing.

OBJECTIVES: Concerns about the coronavirus disease 2019 (COVID-19) pandemic resulted in unprecedented challenges to the management of geriatric hip fractures. We aimed to evaluate the effects of the COVID-19 surge on the time to surgery and 1 year mortality in geriatric patients with hip fracture at a large, urban Level 1 trauma center in Beijing, and to guide the management of geriatric hip fracture patients throughout the COVID-19 pandemic. METHODS: This single-center retrospective study included consecutive patients aged ≥65 years and injured 3 weeks prior to admission. Demographic and surgical data were collected between January 20 and May 31, 2020, and from the same period in 2019. Mortality data and functional status were collected at follow-up of 1-year after surgery. The primary outcomes were time to surgery and 1 year mortality. RESULTS: There were no significant differences in sex, fracture type, and surgical pattern between the 2020 (n = 261) and 2019 time-matched (n = 307) cohorts. The time from admission to surgery was significantly delayed in the 2020 cohort compared with that in the 2019 cohort (48.9 h vs 20.5 h, p < 0.001). Fewer patients underwent surgery within 48 h in the 2020 cohort (65.5% vs 87.6%, p < 0.001). Surgical delay was also associated with an increased risk of inpatient complications (30.2% vs 20.8%, p = 0.010), however there was no significant difference in the 1-year mortality rate, nor between pre-injury and 1 year follow-up mobility as assessed by Parker score. Only approximately half of the patients in both groups completely returned to their pre-injury mobility levels. CONCLUSIONS: The COVID-19 pandemic has significantly increased the surgery waiting time for geriatric patients with hip fractures, which resulted in increased inpatient complications without a higher mortality rate within 1 year. This reinforces the importance of maintaining timely and protocolized care for geriatric hip fractures throughout any subsequent waves of the pandemic.

Perioperative Protocol of Ankle Fracture and Distal Radius Fracture Based on Enhanced Recovery after Surgery Program: A Multicenter Prospective Clinical Controlled study.

Background: The enhanced recovery after surgery (ERAS) program is aimed to shorten patients' recovery process and improve clinical outcomes. This study aimed to compare the outcomes between the ERAS program and the traditional pathway among patients with ankle fracture and distal radius fracture. Methods: This is a multicenter prospective clinical controlled study consisting of 323 consecutive adults with ankle fracture from 12 centers and 323 consecutive adults with distal radial fracture from 13 centers scheduled for open reduction and internal fixation between January 2017 and December 2018. According to the perioperative protocol, patients were divided into two groups: the ERAS group and the traditional group. The primary outcome was the patients' satisfaction of the whole treatment on discharge and at 6 months postoperatively. The secondary outcomes include delapsed time between admission and surgery, length of hospital stay, postoperative complications, functional score, and the MOS item short form health survey-36. Results: Data describing 772 patients with ankle fracture and 658 patients with distal radius fracture were collected, of which 323 patients with ankle fracture and 323 patients with distal radial fracture were included for analysis. The patients in the ERAS group showed higher satisfaction levels on discharge and at 6 months postoperatively than in the traditional group (P < 0.001). In the subgroup analysis, patients with distal radial fracture in the ERAS group were more satisfied with the treatment (P=0.001). Furthermore, patients with ankle fracture had less time in bed (P < 0.001) and shorter hospital stay (P < 0.001) and patients with distal radial fracture received surgery quickly after being admitted into the ward in the ERAS group than in the traditional group (P=0.001). Conclusions: Perioperative protocol based on the ERAS program was associated with high satisfaction levels, less time in bed, and short hospital stay without increased complication rate and decreased functional outcomes.

Research on the Error of Global Positioning System Based on Time Series Analysis.

Due to the poor dynamic positioning precision of the Global Positioning System (GPS), Time Series Analysis (TSA) and Kalman filter technology are used to construct the positioning error of GPS. According to the statistical characteristics of the autocorrelation function and partial autocorrelation function of sample data, the Autoregressive (AR) model which is based on a Kalman filter is determined, and the error model of GPS is combined with a Kalman filter to eliminate the random error in GPS dynamic positioning data. The least square method is used for model parameter estimation and adaptability tests, and the experimental results show that the absolute value of the maximum error of longitude and latitude, the mean square error of longitude and latitude and average absolute error of longitude and latitude are all reduced, and the dynamic positioning precision after correction has been significantly improved.

The prokaryotic community, physicochemical properties and flavors dynamics and their correlations in fermented grains for Chinese strong-flavor Baijiu production.

Fermented grain (FG), a complex and unique ecosystem, is the main microbial habitats, biochemical reaction system and direct source of flavor compounds for the Chinese strong-flavor Baijiu (CSFB) production. However, the dynamics of physicochemical properties, prokaryotic community and flavor compounds of FGs during the long-term fermentation process are still not completely clear. Here, the above topics on FGs in the actual production process were comprehensively studied by using a combination of physicochemical analysis, GC-MS detection and Illumina HiSeq sequencing methods. The whole fermentation process could be divided into two stages including early (0-25d) and the later stage (25-60d) based on the dynamics of FG physicochemical properties and the changes of prokaryotic community diversity. A total of 41phyla and 364 genera were detected, and 9 of them were dominant genera in FG complex ecosystem, including Lactobacillus, Pediococcus, Ochrobactrum, Bacillus etc. Among them, the dynamics of 29 top10 genera in FGs were mainly influenced by the starch and total acid, followed by NH4+ and ethanol, and 7 genera (hubs, e.g., Clostridium, Methanosaeta, Bacillus, etc.) of them may play important roles in FG ecosystem stability. A total of 71 volatiles including 33 esters, 14 alcohols, 9 fatty acids, 5 phenols, and 10 other compounds were detected in the FGs, and most of them formed in the early stage. Some important flavor substances (e.g., ethyl octanoate, 3-methylbutanol, hexanoate, etc.) increased in the later stage. Moreover, the formation of some flavor compound might require multiple microbes involved. For instance, ten of the top10 genera, including Lactobacillus, Clostridium, Methanosarcina, Sedimentibacter, Bacillus, etc., were significantly and positively correlated with four important esters. This study may help to clarify the complex correlations among prokaryotic community, physicochemical properties and flavors, allow the improvement of CSFB quality by using bioaugmentation and/or controlling environmental factors, and shed more light on the ecological rules guiding community assembly in FGs.

Isolated Shear Fracture of the Metatarsal Head in Lesser Toes Treated With ORIF: Case Series.

BACKGROUND: Isolated shear fractures of a metatarsal head in the lesser toes are rare in clinical practice. We report the clinical and imaging characteristics, and treatment results, of these fractures. METHODS: A retrospective consecutive case-series study was performed on 7 patients with symptomatic isolated shear fracture of a metatarsal head in the lesser toes who were operatively treated using open reduction and internal fixation (ORIF). Radiographs and computed tomographic (CT) scans of the patients were analyzed. The American Orthopaedic Foot & Ankle Society-lesser metatarsophalangeal-interphalangeal (AOFAS-LMI) score, visual analog scale (VAS) score, and passive dorsiflexion range of motion (ROM) of the metatarsophalangeal (MTP) joint were determined preoperatively and at final follow-up. Postoperative complications were also recorded. RESULTS: There were 5 males and 2 females, with a mean age of 21 years (range, 16-36) at the time of surgery. Four fractures occurred at the fourth metatarsal. There were 3 chronic cases, 1 was not diagnosed initially; the other 2 failed conservative treatment. The main symptom of the chronic fractures was limited dorsiflexion at the MTP joint. Preoperative radiographs and CT scans revealed dorsal displacement of the fragment without dislocation of the MTP joint. At the final follow-up (mean, 17.4 months; range 9-27), the AOFAS-LMI scores had improved from 70.6 (range, 59-79) preoperatively to 93.3 (range, 92-100) (P = .001). VAS scores showed a decrease in pain from 4.0 to 0.0 (P = .016). Mean passive dorsiflexion ROM of the MTP joint improved significantly from 8.6 degrees preoperatively to 35.7 degrees at final follow-up (P < .001). All patients returned to their respective preinjury activity levels. CONCLUSION: Patients with an acute or chronic isolated shear fracture of a metatarsal head in the lesser toes treated by ORIF achieved good short-term clinical and radiologic outcomes. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Clinical Study of Ankle Fracture Combined With Deltoid Ligament Injury: Repair or Not? A Retrospective, Comparative Study.

This study retrospectively evaluated patients with ankle fracture to compare the prognosis between patients who had primary repair of the superficial deltoid ligament and those who did not. A total of 71 patients with ankle fracture and fracture-dislocation combined with deltoid ligament injury were divided into 2 groups: repair of superficial layer group (33 cases) and nonrepair group (38 cases). For the repair group, patients first underwent open reduction and internal fixation of the lateral malleolus and received a stress test. If the syndesmosis was widened, it would undergo fixation of the syndesmosis with screws. If instability of the ankle joint was observed, patients might further undergo repair of the superficial deltoid ligament. Ultimately, postoperative functions were evaluated using the Philips and Schwartz scale. All patients achieved bony union without significant pain. In the repair group, plantar and dorsi flexions were 2.5 ± 4.2° (range 0 to 10) and 7 ± 7.1° (range 0 to 20) less than the normal side, respectively. In the nonrepair group, the plantar and dorsi flexions were 2.8 ± 4.6° (range 0 to 10) and 6.6 ± 5.9° (range 0 to 20) less than the normal side. Meanwhile, the Philips and Schwartz scores of the repair and nonrepair groups were 92.5 ± 4.4 (range 80 to 100) and 93.4 ± 3.8 (range 85 to 100), respectively. But the difference of prognosis between the 2 groups was not statistically significant. In conclusion, for ankle joint fracture combined with deltoid ligament injury, routinely exploring or repairing the deltoid ligament was not recommended, but repair of the deltoid ligament increased stability of the ankle joint in the early postoperative stage.

Influence of Electrostatic Forces on the Vibrational Characteristics of Resonators for Coriolis Vibratory Gyroscopes.

The Coriolis Vibratory Gyroscopes are a type of sensors that measure angular velocities through the Coriolis effect. The resonator is the critical component of the CVGs, the vibrational characteristics of which, including the resonant frequency, frequency mismatch, Q factor, and Q factor asymmetry, have a great influence on the performance of CVG. The frequency mismatch and Q factor of the resonator, in particular, directly determine the precision and drift characteristics of the gyroscope. Although the frequency mismatch and Q factor are natural properties of the resonator, they can change with external conditions, such as temperature, pressure, and external forces. In this paper, the influence of electrostatic forces on the vibrational characteristics of the fused silica cylindrical resonator is investigated. Experiments were performed on a fused silica cylindrical resonator coated with Cr/Au films. It was shown that the resonant frequency, frequency mismatch, and the decay time slightly decreased with electrostatic forces, while the decay time split increased. Lower capacitive gaps and larger applied voltages resulted in lower frequency mismatch and lower decay time. This phenomenon was theoretically analyzed, and the variation trends of results were consistent with the theoretical analysis. This study indicates that, for fused silica cylindrical resonator with electrostatic transduction, the electrostatic influence on the Q factor and frequency, although small, should be considered when designing the capacitive gap and choosing bias voltages.

Bipartite mechanism for laminin-integrin interactions: Identification of the integrin-binding site in LG domains of the laminin α chain.

Laminins are major cell-adhesive proteins consisting of α, ß, and γ chains, in which the three C-terminal globular domains of the α chain (LMα/LG1-3) and the C-terminal tail region of the γ1 chain (LMγ1-tail) are required for binding to integrin. Despite the recent progress on the role of LMγ1-tail in coordinating the metal ion-dependent adhesion site of the integrin ß subunit, the mechanism by which LMα/LG1-3 interacts with integrin remains to be elucidated. We found that basic residues on the bottom face of LMα5/LG2 are required for binding laminin-511 to α6ß1 integrin. Intermolecular cysteine scanning assays demonstrated that the basic residues in LMα5/LG2 were in contact with the acidic residues within the laminin-binding X1 region of the integrin α subunit in the laminin-integrin complex. These results indicate that LMα5/LG2 interacts directly with the integrin α subunit and comprises a bipartite integrin binding site of laminin-511 with the LMγ1-tail.

Analysis of radial head and coronoid process fractures in terrible triad of elbow.

PURPOSE: To describe the morphological characteristics of radial head and coronoid fractures and evaluate the relationship of two fracture patterns in terrible triad. METHODS: Distributions of all types of radial head and coronoid fractures according to the Mason, Regan-Morrey, and O'Driscoll classifications were firstly described by reviewing radiographs and computed tomography scans in 92 consecutive terrible triads. Then, distributions of all combinations of radial head and coronoid fractures were reported. Correlation analysis between severity of radial head and coronoid fractures was finally performed. RESULTS: In radial head fractures, Mason 2 accounted for 68%, Mason 3 accounted for 32%, and no Mason 1 was found. In coronoid fractures, there were 29 type 1, 44 type 2, and 19 type 3 in Regan-Morrey classification and 72 type 1, one type 2, and 19 type 3 in O'Driscoll classification. There were 28 M2R2, 23 M2R1, 16 M3R2, 12 M2R3, seven M3R3, and six M3R1 in combined Mason and Regan-Morrey type. There were 53 M2O1, 19 M3O1, 10 M3O3, nine M2O3, and one M2O2 in combined Mason and O'Driscoll type. A weak correlation was found between radial head and coronoid fractures. CONCLUSIONS: In terrible triad injuries, the most common type of radial head fracture is Mason 2, while the most common type of coronoid fracture is Regan-Morrey type 2 or O'Driscoll type 1. In combinations of two fracture patterns, M2R2 or M2O1 is the most common. Severity of radial head fractures is weakly correlated with coronoid fractures.

Does routinely repairing deltoid ligament injuries in type B ankle joint fractures influence long term outcomes?

Deltoid ligament reconstruction following type B ankle fractures continues to generate a vivid discussion amongst trauma surgeons. There is a difference of opinion as to whether operative or non operative treatment should prevail. We therefore conducted a prospective comparative cohort study to determine whether it is necessary to routinely repair the injured deltoid ligaments. 41 Type B ankle joint fracture patients were enrolled, all the patients were associated with deltoid ligament ruptures and lateral/posterior-lateral dislocation of talus. After fixation of the lateral malleolus fracture, 12 patients were treated by superficial deltoid ligaments repairing, 16 patients with deep components augmentation, 13 patients had no direct surgical intervention. In the deep components group, the planter and the dorsi flexion was 3.2° (0-10°) and 8.8° (0-15°) less than the normal side. In the superficial components group, plantar and dorsi flexion was 0.8° (0-5°) and 4.2° (0-15°) less than the normal side. In the non-repairing group, the plantar and dorsi flexion was 2.4° (0-10°) and 5.6° (0-20°) less than the normal side. Overall, no significant statistical difference was observed comparing the 3 groups. In addition, no statistically significant inter-group differences were evident in terms of measurement of the ankle medial clear space and the clinical and functional outcomes recorded. In conclusion, the results of this study do not support routine exposure and repairing of the injured deltoid ligaments.

Wound and Sural Nerve Complications of the Sinus Tarsi Approach for Calcaneus Fractures.

Background The purpose of this study was to evaluate the optimal timing and measures of the sinus tarsi approach for calcaneus fractures to avoid iatrogenic injury of the sural nerve and to assess for wound complications. METHODS: A case series of 53 patients with calcaneus fractures treated by a single surgeon with the sinus tarsi approach was retrospectively analyzed. On the basis of the delay time from injury to surgery, patients were classified into 4 groups: immediate (0-3 days), early (4-6 days), intermediate (7-14 days), and late (14-18 days). All patients were followed for at least 1 year to observe wound conditions. The rate of wound complications and iatrogenic sural nerve injury was described. Incisions were classified into 2 groups: group A included patients with incisions extending posterior to the lateral malleolus, and group B included patients with incisions confined anterior to the lateral malleolus. The rates of nerve injury were compared between both groups. Forty-three patients with 52 Sanders type II fractures were included. RESULTS: The average time to surgery from injury was 8.8 days (range, 0-18 days). The overall postoperative rate of wound complications was 5.8% (3 of 52). In the immediate group, deep infections and wound necrosis were found in 2 of 8 fractures (25%). In the early group, 1 of 15 fractures developed superficial infection (6.7%). In the intermediate and late groups, no wound complication was identified. Iatrogenic sural nerve injury was recorded in 5 of 52 patients (9.6%). Group A had 33% (4 of 12) nerve injuries and group B had 2.5% (1 of 40) ( P = .009). In 70% of cases, a main branch of the sural nerve was directly under the incision. CONCLUSIONS: The sinus tarsi approach was generally effective and safe for calcaneus fractures. However, it was relatively risky to perform open reduction and internal fixation by the sinus tarsi approach within 6 days of injury. Because the sural nerve is in the vicinity of the approach, iatrogenic injury should be avoided by the use of careful planning and meticulous manipulations. Level of Evidence Therapeutic; Level III, comparative study.

Anterior Subcutaneous Transposition of the Ulnar Nerve Affects Elbow Range of Motion: A Mean 13.5 Years of Follow-up.

BACKGROUND: Surgical decompression of the ulnar nerve is effective for cubital tunnel syndrome. However, deep approaches may result in iatrogenic elbow stiffness. This long-term study was to evaluate the range of motion (ROM) of the elbow and functional outcomes after anterior subcutaneous transposition. METHODS: A total of 115 patients (78 male and 37 female; mean age: 46.6 years) who underwent anterior subcutaneous transposition of the ulnar nerve between 2001 and 2005 were evaluated retrospectively; mean follow-up was 13.5 years. Elbow ROM was measured as flexion arc, flexion, and extension preoperatively and at the final follow-up, and compared via a mixed analysis of variance adjusting for age. Neuropathy was assessed preoperatively using a modified McGowan neuropathy grade and postoperatively using modified Wilson-Krout criteria. An ordinal logistic regression analysis used postoperative modified Wilson-Krout criteria as the outcome and preoperative factors as predictors. RESULTS: Preoperative McGowan grades were Grade 1 in 14 patients (12.2%), Grade 2A in 28 (24.3%), Grade 2B in 53 (46.1%), and Grade 3 in 20 (17.4%) patients. Postoperatively, 66 patients (57.4%) had excellent results, 26 (22.6%) had good results, 16 (13.9%) had fair results, and 7 (6.1%) had poor results at the final follow-up, as per the Wilson-Krout criteria. There were no complications. Pre- and postoperative elbow ROM was significantly decreased in patients with previous trauma or surgery of the elbow compared with those without (P < 0.05). Anterior subcutaneous transposition of the ulnar nerve did not significantly affect elbow ROM regardless of previous trauma or surgical history nor preoperative ROM (P > 0.05), after adjusting for age. Patients with prolonged symptoms prior to surgery and worse neuropathy tended to have less satisfactory functional outcomes (P < 0.05), after adjusting for covariates. CONCLUSIONS: Anterior subcutaneous transposition of the ulnar nerve is an effective and reliable treatment of cubital tunnel syndrome with satisfactory outcomes and minimal effect on elbow ROM.

Recombinant laminin fragments endowed with collagen-binding activity: A tool for conferring laminin-like cell-adhesive activity to collagen matrices.

Laminins are major components of basement membranes that sustain a wide variety of stem cells. Among 15 laminin isoforms, laminin-511 and its E8 fragment (LM511E8) have been shown to strongly promote the adhesion and proliferation of human pluripotent stem cells. The aim of this study was to endow the cell-adhesive activity of laminin-511 on collagen matrices, thereby fabricating collagen-based culture scaffolds for stem cells with defined composition. To achieve this goal, we utilized the collagen-binding domain (CBD) of fibronectin to immobilize LM511E8 on collagen matrices. CBD was attached to the N-termini of individual laminin chains (α5E8, ß1E8, γ1E8), producing LM511E8s having one, two, or three CBDs. While LM511E8 did not bind to collagen, CBD-attached LM511E8s (CBD-LM511E8s) exhibited significant collagen-binding activity, dependent on the number of attached CBDs. Human iPS cells were cultured on collagen-coated plates preloaded with CBD-LM511E8s. Although iPS cells did not attach or grow on collagen, they robustly proliferated on CBD-LM511E8-loaded collagen matrices, similar to the case with LM511E8-coated plates. Importantly, iPS cells proliferated and yielded round-shaped colonies even on collagen gels preloaded with CBD-LM511E8s. These results demonstrate that CBD-attached laminin E8 fragments are promising tools for fabrication of collagen-based matrices having the cell-adhesive activity of laminins.

Probing the acidic residue within the integrin binding site of laminin-511 that interacts with the metal ion-dependent adhesion site of α6ß1 integrin.

Laminins are major cell-adhesive proteins of basement membranes that interact with integrins in a divalent cation-dependent manner. Laminin-511 consists of α5, ß1, and γ1 chains, of which three laminin globular domains of the α5 chain (α5/LG1-3) and a Glu residue in the C-terminal tail of chain γ1 (γ1-Glu1607) are required for binding to integrins. However, it remains unsettled whether the Glu residue in the γ1 tail is involved in integrin binding by coordinating the metal ion in the metal ion-dependent adhesion site of ß1 integrin (ß1-MIDAS), or by stabilizing the conformation of α5/LG1-3. To address this issue, we examined whether α5/LG1-3 contain an acidic residue required for integrin binding that is as critical as the Glu residue in the γ1 tail; to achieve this, we undertook exhaustive alanine substitutions of the 54 acidic residues present in α5/LG1-3 of the E8 fragment of laminin-511 (LM511E8). Most of the alanine mutants possessed α6ß1 integrin binding activities comparable with wild-type LM511E8. Alanine substitution for α5-Asp3198 and Asp3219 caused mild reduction in integrin binding activity, and that for α5-Asp3218 caused severe reduction, possibly resulting from conformational perturbation of α5/LG1-3. When α5-Asp3218 was substituted with asparagine, the resulting mutant possessed significant binding activity to α6ß1 integrin, indicating that α5-Asp3218 is not directly involved in integrin binding through coordination with the metal ion in ß1-MIDAS. Given that substitution of γ1-Glu1607 with glutamine nullified the binding activity to α6ß1 integrin, these results, taken together, support the possibility that the critical acidic residue coordinating the metal ion in ß1-MIDAS is Glu1607 in the γ1 tail, but no such residue is present in α5/LG1-3.

A classification and grading system for Barton fractures.

PURPOSE: We described a morphological classification and grading system for volar Barton fractures. METHODS: We divided these fractures into four types: typical Barton, ulna Barton, radial Barton, comminuted Barton. Moreover, we graded the fractures into two degrees: simple split and split-depression. We retrospectively reviewed all wrist radiographs showing Barton fractures in our hospital between January 2013 and January 2015. We identified 100 cases whose records and radiographs were reviewed and included 36 men and 64 women with a mean age of 50 years (15-78). The morphological classification was applied to the 100 cases by three reviewers on two occasions using the Kappa statistic. RESULTS: The inter- and intra-observer reliability of the morphological classification was 0.71-0.80 and 0.68-0.88, respectively. The distribution of typical, ulna, radial and comminuted Barton type fractures was 69 %, 7 %, 5 % and 19 %, respectively. Grade 2 fractures accounted for 49 % in our series. CONCLUSIONS: This classification and grading system of Barton fractures is likely to have implications in terms of pathophysiology and surgical technique.

Demonstration of a fully integrated superconducting receiver with a 2.7 THz quantum cascade laser.

We demonstrate for the first time the integration of a superconducting hot electron bolometer (HEB) mixer and a quantum cascade laser (QCL) on the same 4-K stage of a single cryostat, which is of particular interest for terahertz (THz) HEB/QCL integrated heterodyne receivers for practical applications. Two key issues are addressed. Firstly, a low power consumption QCL is adopted for preventing its heat dissipation from destroying the HEB's superconductivity. Secondly, a simple spherical lens located on the same 4-K stage is introduced to optimize the coupling between the HEB and the QCL, which has relatively limited output power owing to low input direct current (DC) power. Note that simulation techniques are used to design the HEB/QCL integrated heterodyne receiver to avoid the need for mechanical tuning. The integrated HEB/QCL receiver shows an uncorrected noise temperature of 1500 K at 2.7 THz, which is better than the performance of the same receiver with all the components not integrated.

Nephronectin binds to heparan sulfate proteoglycans via its MAM domain.

Nephronectin is a basement membrane protein comprising five N-terminal epidermal growth factor (EGF)-like repeats, a central linker segment containing an Arg-Gly-Asp (RGD) motif and a C-terminal meprin-A5 protein-receptor protein tyrosine phosphatase µ (MAM) domain. Nephronectin has been shown to interact with α8ß1 integrin through the central linker segment, but its interactions with other molecules remain to be elucidated. Here, we examined the binding of nephronectin to a panel of glycosaminoglycan (GAG) chains. Nephronectin bound strongly to heparin and chondroitin sulfate (CS)-E and moderately to heparan sulfate (HS), but failed to bind to CS-A, CS-C, CS-D, dermatan sulfate and hyaluronic acid. Deletion of the MAM domain severely impaired the binding of nephronectin to heparin but not CS-E, whereas deletion of the EGF-like repeats reduced its binding to CS-E but not heparin, suggesting that nephronectin interacts with CS-E and heparin through the EGF-like repeats and MAM domain, respectively. Consistent with these results, nephronectin bound to agrin and perlecan, which are heparan sulfate proteoglycans (HSPGs) in basement membranes, in HS-dependent manners. Site-directed mutagenesis of the MAM domain revealed that multiple basic amino acid residues in the putative loop regions were involved in the binding of the MAM domain to agrin. The binding of nephronectin to basement membrane HSPGs was further confirmed by in situ nephronectin overlay assays using mouse frozen tissue sections. Taken together, these findings indicate that nephronectin is capable of binding to HSPGs in basement membranes via the MAM domain, and thereby raise the possibility that interactions with basement membrane HSPGs may be involved in the deposition of nephronectin onto basement membranes.