High-Efficiency Blue-Emitting Mn-Ligand passivated CsPbBr3 nanoplatelets

Perovskite nanoplatelets (NPLs), as a promising material to achieve pure blue emission, have attracted significant attention in high gamut displays. However, the high surface-to-volume ratio and the loosely connected ligands of NPLs make them susceptible to degradation from light, air and heat. As a result, NPLs often exhibit low photoluminescence (PL) intensity and instability. Here, an Mn-ligand passivation strategy is proposed, in which Mn-doped DMAPbBr3 is used as a precursor. During the perovskite transformation, Mn2+ ions migrate from the lattice of DMAPbBr3 to the surface of CsPbBr3 NPLs, which have strong binding forces with ligands. The final products Mn-CsPbBr3 (M-CPB) NPLs are then acquired by the ligand-induced ripening growth process, which not only exhibit pure blue emission with narrow full width at half maximum (FWHM), but also possess near-unity PL quantum yields (QYs). Besides, M-CPB NPLs show excellent stability due to the strong Mn-ligand passivation layer. Based on the new growth mechanism discovery, the reaction time can be shortened to several minutes by heating. The innovative growth model proposed in this work will provide a paradigm for designing and optimizing future synthesis schemes.

Development and validation of a pyroptosis-related prognostic signature associated with osteosarcoma metastasis and immune infiltration

Pyroptosis is a programmed cell death, which has garnered increasing attention because it relates to the immune and therapy response. However, few studies focus on the application of pyroptosis-related genes (PRGs) in predicting osteosarcoma (OS) patients' prognoses. In this study, the gene expression and clinical information of OS patients were downloaded from the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database. Based on these PRGs and unsupervised clustering analysis, all OS samples can be classified into 2 clusters. The 8 key differential expressions for PRGs (LAG3, ITGAM, CCL2, TLR4, IL2RA, PTPRC, FCGR2B, and CD5) were established through the univariate Cox regression and utilized to calculate the risk score of all samples. According to the 8-gene signature, OS samples can be divided into high and low-risk groups and correlation analysis can be performed using immune cell infiltration and immune checkpoints. Finally, we developed a nomogram to improve the PRG-predictive model in clinical application. We verified the predictive performance using receiver operating characteristic (ROC) and calibration curves. There were significant differences in survival, immune cell infiltration and immune checkpoints between the low and high-risk groups. A nomogram was developed with clinical indicators and the risk scores were effective in predicting the prognosis of patients with OS. In this study, a prognostic model was constructed based on 8 PRGs were proved to be independent prognostic factors of OS and associated with tumor immune microenvironment. These 8 prognostic genes were involved in OS development and may serve as new targets for developing therapeutic drugs.

CAR-NK cells in combination therapy against cancer: A potential paradigm

Various preclinical and a limited number of clinical studies of CAR-NK cells have shown promising results: efficient elimination of target cells without side effects similar to CAR-T therapy. However, the homing and infiltration abilities of CAR-NK cells are poor due to the inhibitory tumor microenvironment. From the perspective of clinical treatment strategies, combined with the biological and tumor microenvironment characteristics of NK cells, CAR-NK combination therapy strategies with anti-PD-1/PD-L1, radiotherapy and chemotherapy, kinase inhibitors, proteasome inhibitors, STING agonist, oncolytic virus, photothermal therapy, can greatly promote the proliferation, migration and cytotoxicity of the NK cells. In this review, we will summarize the targets selection, structure constructions and combinational therapies of CAR-NK cells for tumors to provide feasible combination strategies for overcoming the inhibitory tumor microenvironment and improving the efficacy of CAR-NK cells.

Highly efficient and stable Cs3Mn0.93Zn0.07Br5@SiO2 for wide color gamut backlight displays

Mn-based perovskites have become a new candidate material for backlight display applications. However, low efficiency and poor stability are the key problems limiting the application of Mn-based perovskites. In this work, Zn-doped and SiO2-encapsulated Cs3MnBr5, denoted as Cs3Mn0.93Zn0.07Br5@SiO2 (CMZBS), was successfully synthesized to improve the photoluminescence quantum yield (PLQY) and stability. After Zn doping, the PLQY increased from 51% to 72% due to the reduction in the energy transfer between [MnBr4]2-. The PLQY can be further improved to 80% after coating SiO2. Compared with Cs3MnBr5 (CMB), CMZBS showed better stability against thermal, air, light, and polar solvents (ethanol and isopropanol). In addition, a white LED (WLED) device with a CIE of (0.323, 0.325) was fabricated by integrating CMZBS and the red phosphor K2SiF6:Mn4+ on a 465 nm blue GaN chip, which exhibited a high luminous efficiency of 92 lm W-1 and excellent stability, demonstrating its great potential application in wide color gamut displays.

Highly efficient and robust multi-color afterglow of ZnO nanoparticles

Room temperature phosphorescence (RTP) materials are widely used in various fields. However, the realization of multicolor RTP via facile approaches still remains a great challenge. In this study, we propose an in situ hydrolysis method using different solvents to synthesize blue, green, and yellow phosphorescence ZnO/SiO2 composites. By investigating the photoluminescence (PL) and phosphorescence mechanisms of ZnO/SiO2 composites, it is discovered that the solvents not only introduce impurities to ZnO but also affect the position of defect energy levels, leading to the variation in luminescent performance. Meanwhile, the as-synthesized ZnO/SiO2 composites exhibit stable PL and phosphorescence under extreme conditions. Specifically, the PL and phosphorescence properties of the composites are well maintained at high temperature (523 K) or underwater. Owing to the multicolor phosphorescence properties of these ZnO/SiO2 products, herein, we demonstrate that ZnO/SiO2 composites can act as new smart materials for information encryption, fingerprint identification, and white light-emitting diodes (WLEDs).

Energetic Electron Precipitation Driven by Electromagnetic Ion Cyclotron Waves from ELFIN's Low Altitude Perspective

We review comprehensive observations of electromagnetic ion cyclotron (EMIC) wave-driven energetic electron precipitation using data collected by the energetic electron detector on the Electron Losses and Fields InvestigatioN (ELFIN) mission, two polar-orbiting low-altitude spinning CubeSats, measuring 50-5000 keV electrons with good pitch-angle and energy resolution. EMIC wave-driven precipitation exhibits a distinct signature in energy-spectrograms of the precipitating-to-trapped flux ratio: peaks at >0.5 MeV which are abrupt (bursty) (lasting ∼17 s, or Δ L ∼ 0.56 ) with significant substructure (occasionally down to sub-second timescale). We attribute the bursty nature of the precipitation to the spatial extent and structuredness of the wave field at the equator. Multiple ELFIN passes over the same MLT sector allow us to study the spatial and temporal evolution of the EMIC wave - electron interaction region. Case studies employing conjugate ground-based or equatorial observations of the EMIC waves reveal that the energy of moderate and strong precipitation at ELFIN approximately agrees with theoretical expectations for cyclotron resonant interactions in a cold plasma. Using multiple years of ELFIN data uniformly distributed in local time, we assemble a statistical database of ∼50 events of strong EMIC wave-driven precipitation. Most reside at L ∼ 5 - 7 at dusk, while a smaller subset exists at L ∼ 8 - 12 at post-midnight. The energies of the peak-precipitation ratio and of the half-peak precipitation ratio (our proxy for the minimum resonance energy) exhibit an L -shell dependence in good agreement with theoretical estimates based on prior statistical observations of EMIC wave power spectra. The precipitation ratio's spectral shape for the most intense events has an exponential falloff away from the peak (i.e., on either side of ∼ 1.45 MeV). It too agrees well with quasi-linear diffusion theory based on prior statistics of wave spectra. It should be noted though that this diffusive treatment likely includes effects from nonlinear resonant interactions (especially at high energies) and nonresonant effects from sharp wave packet edges (at low energies). Sub-MeV electron precipitation observed concurrently with strong EMIC wave-driven >1 MeV precipitation has a spectral shape that is consistent with efficient pitch-angle scattering down to ∼ 200-300 keV by much less intense higher frequency EMIC waves at dusk (where such waves are most frequent). At ∼100 keV, whistler-mode chorus may be implicated in concurrent precipitation. These results confirm the critical role of EMIC waves in driving relativistic electron losses. Nonlinear effects may abound and require further investigation.

Metal-Ion-Doped Manganese Halide Hybrids with Tunable Emission for Advanced Anti-Counterfeiting

Stimuli-responsive luminescent materials have received great attention for their potential application in anti-counterfeiting and information encryption. Manganese halide hybrids have been considered an efficient stimuli-responsive luminescent material due to their low price and adjustable photoluminescence (PL). However, the photoluminescence quantum yield (PLQY) of PEA₂MnBr₄ is relatively low. Herein, Zn²⁺- and Pb²⁺-doped PEA₂MnBr₄ samples are synthesized, and show an intense green emission and orange emission, respectively. After doping with Zn²⁺, the PLQY of PEA₂MnBr₄ is elevated from 9% to 40%. We have found that green emitting Zn²⁺-doped PEA₂MnBr₄ could transform to a pink color after being exposed to air for several seconds and the reversible transformation from pink to green was achieved by using heating treatment. Benefiting from this property, an anti-counterfeiting label is fabricated, which exhibits excellent "pink-green-pink" cycle capability. Pb²⁺-doped PEA₂Mn_0.88Zn_0.12Br₄ is acquired by cation exchange reaction, which shows intense orange emission with a high QY of 85%. The PL of Pb²⁺-doped PEA₂Mn_0.88Zn_0.12Br₄ decreases with increasing temperature. Hence, the encrypted multilayer composite film is fabricated relying on the different thermal responses of Zn²⁺- and Pb²⁺-doped PEA₂MnBr₄, whereby the encrypted information can be read out by thermal treatment.

Intergenerational effects of parental [Cnmim]BF4 (n = 4, 6, 8) ionic liquids exposure on zebrafish development based on transcriptomic analysis

Ionic liquids (ILs) have been developed as alternatives to traditional solvents, and their toxicity may be affected by alkyl chain length. Currently, there is limited evidence for whether parental exposure to different alkyl chain length ILs will induce intergenerational toxicity in zebrafish offspring. To address this knowledge gap, the parental zebrafish (F0) were exposed to 25 mg/L [C_nmim]BF₄ (n = 4, 6, 8) for 7 days. Following this, fertilized F1 embryos from the exposed parents were reared in clean water for 120 h. Increased mortality, higher deformity rate, increased pericardial edema rate, and a shorter swimming distance and average speed were detected in the unexposed F1 embryonic larvae from the exposed F0 compared to the F1 generation from the unexposed F0. Parental exposure to [C_nmim]BF₄ (n = 4, 6, 8) resulted in cardiac malformations and dysfunction in F1 larvae, including increased pericardial areas, increased yolk sac areas and decreased heart rate. Moreover, the intergenerational toxicity of [C_nmim]BF₄ (n = 4, 6, 8) in F1 offspring appeared to be alkyl chain length-dependent. Parental [C_nmim]BF₄ (n = 4, 6, 8) exposure led to global transcriptomic changes involved in developmental processes, nervous system process, cardiomyopathy, cardiac muscle contraction, and metabolic signalling pathways such as PI3K-Akt, PPAR and cAMP pathways in unexposed F1 offspring. Overall, the present study provides evidence that the neurotoxicity and cardiotoxicity of ILs in zebrafish can be markedly transmitted to offspring, and the intergenerational developmental toxicity is probably linked to transcriptomic alterations, highlighting the necessity of assessing ILs' environmental safety and human health risks.

Fluorescent detection of brown spot of tobacco caused by Alternaria alternata based on lambda exonuclease-induced DNAzyme amplification

A rapid, simple, and sensitive fluorescent detection method for brown spot of tobacco is established by lambda exonuclease-induced Mg²⁺-dependent DNAzyme amplification. It contains hybridization of the Alternaria alternata genome and HP1, digestion of the 5'-phosphorylated strand of the hybrid dsDNA by lambda exonuclease, acquisition of complete Mg²⁺-dependent DNAzyme, cleavage of the substrate modified with FAM and BHQ-1, and fluorescent detection. The proposed assay exhibits good sensitivity (10 pg L^-1), selectivity and reproducibility. The method does not require pure DNA and expensive instruments, and can be performed within 2.5 hours. To the best of our knowledge, this is the first report of fluorescent detection of Alternaria alternata and its tobacco field samples. This method can be applied to the rapid and sensitive detection of Alternaria alternata in tobacco and its seedlings, and is particularly important for the green prevention and control of tobacco brown spot disease.

Multidisciplinary management of pediatric malignant rhabdoid tumor based on 5 years of experience at a tertiary care center

OBJECTIVE

Malignant rhabdoid tumor (MRT) is a highly aggressive tumor that occurs mostly in young children with extremely poor prognosis. Standardized and effective treatment strategies for MRT have yet to be established because of its rarity. Here, we report our single-institutional experience involving MRT treatment.

METHODS

Patients with newly diagnosed MRT between March 2016 and October 2021 were included. The clinical characteristic, treatment-related toxicities, clinical outcomes, and prognostic factor were retrospectively analyzed.

RESULTS

A total of 18 patients with MRT were enrolled during the 5 years. The median age was 42.8 months (range 10 to 82 years). Among the 18 patients, 9 patients died after a median of follow-up 26 months (range 3 to 42 months). The 1-year event-free survival (EFS) and 3-year overall survival (OS) rates of the entire cohort were 63% (95% CI 46% to 74%) and 67% (95% CI 49% to 82%), respectively. Univariate analysis of patients who underwent gross or total resection followed by adjuvant chemotherapy and radiotherapy demonstrated an improvement in 1-year EFS. However, only gross resection and total resection predicted a better 3-year OS.

CONCLUSIONS

Surgical excision is still the mainstream treatment for MRT. Postoperative adjuvant treatments including chemotherapy and radiotherapy contribute to improved disease control rate. Our single-institute experience may provide insights into the multimodal treatment of MRT.

Mn-Doped Multiple Quantum Well Perovskites for Efficient Large-Area Luminescent Solar Concentrators

Luminescent solar concentrators (LSCs) can be used as large-area sunlight collectors, which show great potential in the application of building-integrated photovoltaic areas. Achieving highly efficient LSCs requires the suppression of reabsorption losses while maintaining a high photoluminescence quantum yield (PLQY) and broad absorption. Perovskites as the superstar fluorophores have recently emerged as candidates for large-area LSCs. However, highly emissive perovskites with a large Stokes shift and broad absorption have not been obtained up to now. Here, we devised a facile synthetic route to obtain Mn-doped multiple quantum well (MQW) Br-based perovskites. The Br-based perovskite host ensures broad absorption. Efficient energy transfer from the exciton to the Mn dopant produces a large Stokes shift and high PLQY simultaneously. By further coating the perovskites with Al₂O₃, the stability and PLQY are greatly elevated. A large area of liquid LSC (40 cm × 40 cm × 0.5 cm) is fabricated, which possesses an internal quantum efficiency (η_int) of 47% and an optical conversion efficiency (η_opt) reaching 11 ± 1%, which shows the highest value for large-area LSCs.

Digital Quantification Method for Sensitive Point-of-Care Detection of Salivary Uric Acid Using Smartphone-Assisted μPADs

Uric acid (UA) is an important biomarker for many diseases. A sensitive point-of-care (POC) testing platform is designed for the digital quantification of salivary UA based on a colorimetric reaction on an easy-to-build smartphone-assisted microfluidic paper-based analytical device (SμPAD). UA levels are quantified according to the color intensity of Prussian blue on the SμPAD with the aid of a MATLAB code or a smartphone APP. A color correction method is specifically applied to exclude the light effect. Together with the engineering design of SμPADs, the background calibration function with the APP increases the UA sensitivity by 100-fold to reach 0.1 ppm with a linear range of 0.1-200 ppm. The assay time is less than 10 min. SμPADs demonstrate a correlation of 0.97 with a commercial UA kit for the detection of salivary UA in clinical samples. SμPADs provide a sensitive, fast, affordable, and reliable tool for the noninvasive POC quantification of salivary UA for early diagnosis of abnormal UA level-associated health conditions.

SERS-based CRISPR/Cas assay on microfluidic paper analytical devices for supersensitive detection of pathogenic bacteria in foods

Rapid and point-of-need (PON) detection of bacteria is crucial to directly provide rapid and reliable diagnostics information during on-site tests, allowing more room for taking proactive measures. By taking the multifaceted advantages of CRISPR/Cas12a and surface-enhanced Raman scattering (SERS), for the first time, we designed a recombinase polymerase amplification (RPA)-integrated microfluidic paper-based analytical device (μPAD), coined RPA-Cas12a-μPAD for supersensitive SERS detection. Single-stranded DNAs were designed to "pull down" SERS nanoprobes. The amplicons of the invA gene triggered the trans-cleavage of Cas12a, resulting in the indiscriminate shredding of linker ssDNA. Thus, the degree of aggregation of SERS nanoprobes was dependent on the concentration of Salmonella typhimurium (S. typhi), which was determined on a μPAD and monitored by a Raman spectrometer. The limit of detection for S. typhi was approximately 3-4 CFU/mL for spiked milk and meat samples with a dynamic detection range from 1 to 10⁸ CFU/mL. The RPA-Cas12a-μPAD secured accurate tests for food samples in 45 min. This work expands the reach of CRISPR-based diagnostics (CRISPR-Dx) and provides a novel and robust bacterial PON detection platform.

Meniscus Regeneration With Multipotent Stromal Cell Therapies

Meniscus is a semilunar wedge-shaped structure with fibrocartilaginous tissue, which plays an essential role in preventing the deterioration and degeneration of articular cartilage. Lesions or degenerations of it can lead to the change of biomechanical properties in the joints, which ultimately accelerate the degeneration of articular cartilage. Even with the manual intervention, lesions in the avascular region are difficult to be healed. Recent development in regenerative medicine of multipotent stromal cells (MSCs) has been investigated for the significant therapeutic potential in the repair of meniscal injuries. In this review, we provide a summary of the sources of MSCs involved in repairing and regenerative techniques, as well as the discussion of the avenues to utilizing these cells in MSC therapies. Finally, current progress on biomaterial implants was reviewed.

Treatment of infantile fibrosarcoma: A tertiary care center experience

OBJECTIVE

Infantile fibrosarcoma (IFS) is a highly locally aggressive nonrhabdomyosarcomatous soft tissue sarcoma that most commonly occurs in young infants. There exists no standard treatment this lesion due to its rarity. We shared our treatment experience for IFS in this study.

METHODS

Patients' record between January 2013 and December 2018 were reviewed and patients with newly diagnosed IFS were included. The clinical characteristics, treatment strategy, treatment-related toxicities and clinical outcome were retrospectively analyzed.

RESULTS

Eleven patients were admitted in our center, including 4 girls and 7 boys, and the median age at diagnosis was 5 months (range 1-23 months). Ten patients achieved complete remission (CR) after the completion of initial treatment. The main short-term adverse effects was myelosuppression. Three patients experienced relapse, including two patients with local progression and one patient with distant metastasis. After a median follow-up of 3.5 years (range 1.5-7 years), 9 patients were alive and 2 patients died. The 3-year overall survival (OS) rate was 93.5% (95% CI 83.7-98.2).

CONCLUSION

We formulated the treatment strategy according to group grade and the experience from previous studies, which may be effective and feasible for the treatment of IFS.

The ELFIN Mission

The Electron Loss and Fields Investigation with a Spatio-Temporal Ambiguity-Resolving option (ELFIN-STAR, or heretoforth simply: ELFIN) mission comprises two identical 3-Unit (3U) CubeSats on a polar (∼93^∘ inclination), nearly circular, low-Earth (∼450 km altitude) orbit. Launched on September 15, 2018, ELFIN is expected to have a >2.5 year lifetime. Its primary science objective is to resolve the mechanism of storm-time relativistic electron precipitation, for which electromagnetic ion cyclotron (EMIC) waves are a prime candidate. From its ionospheric vantage point, ELFIN uses its unique pitch-angle-resolving capability to determine whether measured relativistic electron pitch-angle and energy spectra within the loss cone bear the characteristic signatures of scattering by EMIC waves or whether such scattering may be due to other processes. Pairing identical ELFIN satellites with slowly-variable along-track separation allows disambiguation of spatial and temporal evolution of the precipitation over minutes-to-tens-of-minutes timescales, faster than the orbit period of a single low-altitude satellite (T_orbit ∼ 90 min). Each satellite carries an energetic particle detector for electrons (EPDE) that measures 50 keV to 5 MeV electrons with Δ E/E < 40% and a fluxgate magnetometer (FGM) on a ∼72 cm boom that measures magnetic field waves (e.g., EMIC waves) in the range from DC to 5 Hz Nyquist (nominally) with <0.3 nT/sqrt(Hz) noise at 1 Hz. The spinning satellites (T_spin ∼ 3 s) are equipped with magnetorquers (air coils) that permit spin-up or -down and reorientation maneuvers. Using those, the spin axis is placed normal to the orbit plane (nominally), allowing full pitch-angle resolution twice per spin. An energetic particle detector for ions (EPDI) measures 250 keV - 5 MeV ions, addressing secondary science. Funded initially by CalSpace and the University Nanosat Program, ELFIN was selected for flight with joint support from NSF and NASA between 2014 and 2018 and launched by the ELaNa XVIII program on a Delta II rocket (with IceSatII as the primary). Mission operations are currently funded by NASA. Working under experienced UCLA mentors, with advice from The Aerospace Corporation and NASA personnel, more than 250 undergraduates have matured the ELFIN implementation strategy; developed the instruments, satellite, and ground systems and operate the two satellites. ELFIN's already high potential for cutting-edge science return is compounded by concurrent equatorial Heliophysics missions (THEMIS, Arase, Van Allen Probes, MMS) and ground stations. ELFIN's integrated data analysis approach, rapid dissemination strategies via the SPace Environment Data Analysis System (SPEDAS), and data coordination with the Heliophysics/Geospace System Observatory (H/GSO) optimize science yield, enabling the widest community benefits. Several storm-time events have already been captured and are presented herein to demonstrate ELFIN's data analysis methods and potential. These form the basis of on-going studies to resolve the primary mission science objective. Broad energy precipitation events, precipitation bands, and microbursts, clearly seen both at dawn and dusk, extend from tens of keV to >1 MeV. This broad energy range of precipitation indicates that multiple waves are providing scattering concurrently. Many observed events show significant backscattered fluxes, which in the past were hard to resolve by equatorial spacecraft or non-pitch-angle-resolving ionospheric missions. These observations suggest that the ionosphere plays a significant role in modifying magnetospheric electron fluxes and wave-particle interactions. Routine data captures starting in February 2020 and lasting for at least another year, approximately the remainder of the mission lifetime, are expected to provide a very rich dataset to address questions even beyond the primary mission science objective.

[Clinical outcomes of opening coronary chronic total occlusion lesions with the assistance of BridgePoint devices]

Objective: To investigate the safety, efficacy and prognosis of antegrade dissection re-entry (ADR) with the assistance of BridgePoint devices in opening coronary chronic total occlusion (CTO). Methods: A total of 87 consecutive patients, who underwent percutaneous coronary intervention using BridgePoint devices from April 2016 to December 2018 in Xijing Hospital, were included in this study. General information of the selected patients, features of CTO lesions and intraoperative parameters were recorded. Short-term outcomes including technical success rate (defined as achieving TIMI 3 blood flow with residual stenosis<30%), surgical success rate (defined as no major adverse cardiovascular events (MACE) occured while hospitalized), complications, and MACE during hospitalization were observed. MACE included death, recurrent myocardial infarction, target vascular reconstruction (TVR) and cardiac tamponade. Patients were followed up by outpatient or telephone visits at 30 days and 6, 12, 24 and 36 months after discharge. Results: Eighty-seven patients, aged (61±10) years with J-CTO scores (2.49±0.52) were included, and 75(86%) were male. Six patients underwent direct ADR with BridgePoint system, and all were successful. Eighty-one patients underwent rescue ADR using BridgePoint devices, and 62 of them were successful. The success rate of ADR with BridgePoint devices was 78.2% (68/87). Nine out of the 19 failed cases succeeded after the application of rescue antegrade/retrograde technique. The technical success rate was 88.5% (77/87). Coronary perforation occurred in 2 cases (2.3%), one case was treated with covered stent and the other case with tamponade was treated with pericardiocentesis. One patient developed periprocedural myocardial infarction, and one patient suffered from sudden death, and one patient had cardiac tamponade. In-hospital MACE occurred in 3 (3.4%) patients. The surgical success rate was 85.1% (74/87).The procedure time was (175±72)minutes and the amount of contrast used was (449±155)ml. During a follow-up of 17(11, 26) months, the incidence of MACE within 30 days was 4.7% (4/86), while 10.5% (9/86) within 6 months, 17.4% (15/86) within 17 months. Conclusion: Opening CTO with the assistance of BridgePoint devices is feasible and safe, with high success rate and satisfactory outcome.

CT Manifestations of Novel Coronavirus Pneumonia: A Case Report

Background

Since December 2019, the outbreak of the novel coronavirus has impacted nearly >90,000 people in more than 75 countries. In this case report, we aim to define the chest computed tomography findings of 2019-novel coronavirus associated with pneumonia and its successful resolution after treatment.

Case Report

A fifty-year-old female patient, who is a businesswoman, presented with chief complaints of “fever for one week, diarrhea, anorexia, and asthenia.” Initially, she was given Tamiflu. The influenza A virus serology was negative. Three days later, levofloxacin was started because the patient’s symptoms did not improve. The novel coronavirus nucleic acid test was negative. It was noted that before the onset of the disease, the patient went to Wuhan on a business trip. Despite the given treatment, her body temperature rose to 39.2°C and she was referred to our clinic for further evaluation. Then, chest computed tomography was performed and showed bilateral multifocal ground glass opacities with consolidation which suggested viral pneumonia as a differential diagnosis, and the subsequent 2019-novel coronavirus pneumonia nucleic acid test was positive.

Conclusion

Chest computed tomography offers fast and convenient evaluation of patients with suspected 2019-novel coronavirus pneumonia.

Analysis of the Relationship Between Modic Change and Spinopelvic Parameters in the Sagittal Plane

Background

This study explored relationship between Modic change and spinopelvic parameters in the sagittal plane.

Material/Methods

We divided 80 patients into 4 groups: 60 subjects diagnosed with Modic changes (MC) were enrolled in the MC groups (MC1, MC2, and MC3) with each MC type consisting of 20 subjects, and 60 healthy subjects were enrolled in the control group. Spinopelvic parameters in the sagittal plane were calculated to assess their associations with MC. Multivariate logistic regression was used to explore possible risk factors for MC.

Results

PI and LL in the MC groups were significant smaller than in the control group (p<0.05). PI, SS, and PT were significantly correlated with LL with a correlation coefficient of 0.75_PI, 0.71_SS and 0.69_PT (p<0.05). Multivariate logistic regression of the significant variables showed that PI (less than 43.2°) is an independent significant risk factor for MC. ROC analysis showed that moderate diagnostic value was obtained for the significant variable, with an area under the curve (AUC) of 0.80 (p>0.05).

Conclusions

We concluded that PI is risk factor for MC, and smaller PI is associated with higher incidence of MC.

Genetic Diversity of Listeria monocytogenes Isolates from Invasive Listeriosis in China

Listeria monocytogenes is a deadly foodborne pathogen, and infections can result in meningoencephalitis and sepsis with mortality rates of up to 30%. In this study, we performed comparative whole-genome analysis of 30 clinical isolates sequenced together with 32 previously sequenced clinical and food isolates from China. The data indicate that L. monocytogenes isolates belonging to the clonal complexes (CC) -1, -8, -9, -87, -121, and -155 are present in human clinical cases. The majority of isolates are from CC-87, 9, and 8 and overlap with those CCs previously reported on the basis of multilocus sequence typing for isolates from Chinese food products. Detailed genome analysis of isolates, representative of CCs in clinical and food products, revealed strong similarities both in their core- and accessory genomes indicating that they are highly related. When compared to genome sequences of isolates of a given CC worldwide, clinical isolates of China were distinct and clustered in unified clades. Our data indicate that epidemic clones of L. monocytogenes (CC-87, 9, and 8) with unusually high occurrence of plasmids are unique to China and suggest that common populations of L. monocytogenes clones are present in both clinical and food products in China.

The relationship between magnesium and osteoarthritis of knee: A MOOSE guided systematic review and meta-analysis

The impact of magnesium on risk of knee osteoarthritis (KOE) is still under investigation. This meta-analysis evaluated the relationship between magnesium and risk of KOE.A comprehensive search was performed to identify retrospective cohort study or cross-sectional study of the association between magnesium and KOE from the Cochrane library, PubMed, and Embase. The search time limit was from the establishment of the database to December 2018. Two evaluators selected the literature, extracted the data, and evaluated the quality of the literature according to the inclusion and exclusion criteria, independently. Meta-analysis was performed using RevMan 5.3 software and publication bias was assessed using Begg and Egger test and funnel plot.Finally, 6 studies were included with a total of 15,715 participants. Although higher daily intake of magnesium was associated with a significantly reduced risk of fracture in patients with KOE (OR = 0.66, 95%CI: 0.56, 0.78; P < .00001), it was not significant for lowering the risk of KOE (OR = 0.80; 95% CI: 0.61, 1.04; P = .1). Meta-analysis also showed that population with higher serum magnesium levels had significantly lower risk of KOE (odds ratio (OR) = 0.84; 95% confidence interval (CI): 0.72, 0.98; P = .03). Further subgroup analysis showed that the relationship between serum magnesium level and KOE risk was significantly affected by serum magnesium level (P = .006 for quartiles 4 vs 1).Higher level of magnesium intake was not associated with lower risk of KOE. However, higher daily intake of magnesium may be inversely associated with risk of fracture in KOE patients.

A hybrid sub-lineage of Listeria monocytogenes comprising hypervirulent isolates

The foodborne pathogen Listeria monocytogenes (Lm) is a highly heterogeneous species and currently comprises of 4 evolutionarily distinct lineages. Here, we characterize isolates from severe ovine listeriosis outbreaks that represent a hybrid sub-lineage of the major lineage II (HSL-II) and serotype 4h. HSL-II isolates are highly virulent and exhibit higher organ colonization capacities than well-characterized hypervirulent strains of Lm in an orogastric mouse infection model. The isolates harbour both the Lm Pathogenicity Island (LIPI)-1 and a truncated LIPI-2 locus, encoding sphingomyelinase (SmcL), a virulence factor required for invasion and bacterial translocation from the gut, and other non-contiguous chromosomal segments from another pathogenic species, L. ivanovii. HSL-II isolates exhibit a unique wall teichoic acid (WTA) structure essential for resistance to antimicrobial peptides, bacterial invasion and virulence. The discovery of isolates harbouring pan-species virulence genes of the genus Listeria warrants global efforts to identify further hypervirulent lineages of Lm.

Restoration of osteogenic differentiation by overexpression of cannabinoid receptor 2 in bone marrow mesenchymal stem cells isolated from osteoporotic patients

Cannabinoid receptor 2 (CNR2) has a critical role in osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). CNR2 expression was found to be downregulated in osteoporotic patients. The present study aimed to investigate the functionality of CNR2 in restoring osteogenic differentiation and mineralization of BMSCs isolated from osteoporotic patients. CNR2 was overexpressed in osteoporotic BMSCs by a lentivirus. Alkaline phosphatase (ALP) activity staining and alizarin red S staining were performed to examine the osteogenic differentiation of osteoporotic BMSCs. Reverse-transcription quantitative polymerase chain reaction analysis was performed to examine the expression of osteogenic genes in BMSCs. Western blot analysis was used to study the activation of p38 mitogen-activated protein kinase (MAPK) during osteogenic differentiation of osteoporotic BMSCs after lentivirus-mediated overexpression of CNR2. The results demonstrated that overexpression of CNR2 in osteoporotic BMSCs increased ALP activity, promoted expression of osteogenic genes and enhanced deposition of mineralized extracellular matrix. In addition, phosphorylation of p38 MAPK was found to be increased by overexpression of CNR2. In conclusion, the present study indicated that restoration of CNR2 recovered the osteogenic differentiation of BMSCs isolated from osteoporotic patients. This finding may provide a novel strategy for a treatment approach for osteoporosis.

A Promising Listeria-Vectored Vaccine Induces Th1-Type Immune Responses and Confers Protection Against Tuberculosis

Deaths associated with tuberculosis (TB) is rising and accounted for 1.4 million deaths in 2015 many of which were due to drug-resistant bacteria. Vaccines represent an important medical intervention, but the current Bacilli Calmette-Guerin (BCG) vaccine is not ideal for the protection of teenagers and adults. Therefore, a safe and effective vaccine is urgently needed. In this study, we designed a novel vaccine using an attenuated Listeria monocytogenes strain carrying fusion antigen FbpB-ESAT-6 (rLM) and characterized its safety and protective efficacy against Mycobacterium tuberculosis (M.tb) infection in mice. Compared to the wild type strain yzuLM4 and parental strain LMΔactA/plcB (LM1-2), the virulence of rLM was significantly reduced as judged by its infectious kinetics and LD₅₀ dose. Further characterization of intravenous immunization showed that prime-boost vaccination significantly increased the levels of Th1 cytokines (IFN-γ, IL-17, and IL-6), and enhanced cytotoxic T lymphocyte (CTL) CTLs activity, suggesting that rLM could elicit potent Th1/Th17 responses. More importantly, rLM significantly conferred the protection against M.tb H37Rv challenge. Collectively, our findings indicated that rLM is a novel and useful tool to prevent M.tb infection, and can be potentially be used to boost BCG-primed immunity.

Reduction Levels and the Effects of High-Molecular-Weight Adiponectin via AMPK/eNOS in Chinese Type 2 Diabetes

Aim: This study was to investigate the change of high-molecula-weight (HMW) adiponectin (APN) isoform, the association between type 2 diabetes mellitus (T2DM) and HMW APN isoform, the variation of Disulfide-bond A oxidoreductase-like protein (DsbA-L), the effect of HMW APN isoform on AMP-dependent protein kinase (AMPK) and endothelial nitric oxide synthase (eNOS) in Chinese T2DM. Method: 169 patients aged at (48.7±9.4) years and 107 healthy control subjects aged at (42.6±7.8) years took part in this study. Anthropometric measures of the characters were assayed and different APN isoforms, DsbA-L, AMPK and eNOS levels were determined. Results: Ln(sRAGE) and Ln(Adiponectin) were significantly lower and significantly higher for the other characteristics in T2DM. Ln(Adiponectin) was negatively and significantly correlated with WHR, Ln(triglycerides), fasting plasma glucose, HbA1c (%) in control subjects and T2DM patients. Plasma and adipose tissue total APN and HMW APN were significantly reduced in newly diagnosed T2DM patients. DsbA-L was markedly down-regulated in diabetic adipose tissue. HMW APN caused significant decreases in AMPK and eNOS phosphorylation levels of human umbilical vein endothelial cells (HUVECs). Conclusions: Our results demonstrated that total APN levels was closely related to the risk of T2DM and HMW APN reduction was involved in the diabetic vascular AMPK/eNOS signal pathway. The findings will provide insight into novel therapeutic approaches for reducing the elevated cardiovascular risk associated with T2DM.

Rapamycin reduces severity of senile osteoporosis by activating osteocyte autophagy

SUMMARY

Osteocyte is the orchestrator of bone remolding and decline in osteocyte autophagy is involved in senile osteoporosis. Our results suggested that rapamycin, at least in part by activating osteocyte autophagy, reduced the severity of age-related bone changes in trabecular bone of old male rats.

INTRODUCTION

Previous literatures have showed that osteocyte is the orchestrator of bone remolding and age-related decline in osteocyte number is associated with senile osteoporosis. Autophagy is an important cellular protective mechanism which can preserve osteocyte viability and failure of autophagy in osteocyte with age has been linked to senile osteoporosis. The purpose of this study was to explore whether rapamycin, one activator of autophagy, has protective effects on senile osteoporosis through inducing osteocyte autophagy.

METHODS

Fifty-two 24-month-old male Sprague-Dawley (SD) rats were randomly divided into two groups. Rapamycin (1 mg/kg weight/day) or DMSO vehicle control was administered intraperitoneally for 12 weeks. BMD and bone microstructure were determined by Micro-CT. Fluorochrome labeling of the bones was performed to measure the mineral apposition rate (MAR). TRAP staining was performed to evaluate osteoclast number. The plasma levels of bone turnover markers were also analyzed. The effects of rapamycin on osteocyte autophagy were determined by immunohistochemistry, Western blot, and q-PCR. TUNEL was used to determine the prevalence of osteocyte apoptosis.

RESULTS

Micro-CT evaluation demonstrated that rapamycin had a protective effect on age-related bone loss in trabecular bone. Besides, rapamycin resulted in an obvious increase of MAR and a decrease of osteoclast number in contrast to the control group. Furthermore, rapamycin also induced autophagy in osteocyte demonstrated by increased LC3-positive osteocyte and increased LC3 turnover. In addition, rats treated with rapamycin exhibited decreased apoptosis of osteocyte determined by TUNEL.

CONCLUSIONS

These results suggested that rapamycin, at least in part by activating osteocyte autophagy, reduced the severity of age-related bone changes in trabecular bone of old male rats. Therefore, rapamycin might be a feasible therapeutic approach for senile osteoporosis.

[Prokaryotic expression and immunological characteristics of Mycobacterium tuberculosis Rv1886c]

OBJECTIVE

Ag85B (Rv1886c) is secreted during the early stages of infection by Mycobacterium tuberculosis. The purpose of this study was probed into the immune response against Ag85B in vivo.

METHODS

Ag85B was prokaryotic expressed and identified, its immunological characteristics were evaluated with indirect-ELSIA, Sandwich-ELISA and

RESULTS

Ag85B was mainly expressed in form of inclusion body enzyme-linked immunospot assay (ELISPOT). confirmed by SDS-PAGE. Western blot analysis shows that the fusion protein had good specific reaction with serum of tuberculosis patient and serum of mice immunized with LM-Ag85B. C57BL/6 mice were subcutaneously immunized with Ag85B, the production of IFN-gamma and IL-4 in the spleen cells was determined by Sandwich ELISA, the level of IFN-gamma was significantly higher than that of IL-4 (P < 0.001) in the Ag85B immunization group, it indicated the protein induced Th1-tendency immune responses. Furthermore, purified protein derivative (PPD) used as coating antigen, antibody titer against Ag85B in murine serum reached 1:6400, it was demonstrated that Ag85B could also induce humoral immune responses. Additionally, C57BL/6 mice were intravenously immunized with M. tb H37Rv and bacillus Calmette-Guérin (BCG) respectively for 42 days, M. tb H37Rv group intended to induce Ag85B specific Th1 type immune response, and its ability of eliciting cellular immunity was significantly stronger than BCG group (P < 0.001).

CONCLUSION

Ag85B can affectively induce strongly Th1-tendency immune response and humoral response. Whereas, BCG prime vaccination only can elicit low levels of Ag85B(240-259) specific immune response. The study laid foundation for probing the pathogenic mechanism, the development of novel vaccine and the establishment of clinical diagnostic method.

[Immunological characteristics of Mycobacterium tuberculosis antigen Rv2628]

Antigen Rv2628 of Mycobacterium tuberculosis is associated with latent tuberculosis infection. In this study, Rv2628 was prokaryotic expressed and purified, its immunological characteristics was evaluated with macrophage cell line RAW264.7 and BALB/c mice. The results show that Rv2628 was mainly expressed in form of inclusion body confirmed by SDS-PAGE, and could react with rabbit anti-H37Rv polyclonal antibody detected by Western blotting assay, indicating that the protein had an effective immunoreactivity. The interactions between Rv2628 and macrophage cell line RAW264.7 confirmed that it could effectively induce cells to produce pro-inflammatory cytokines, the relative expression level of IL-6 mRNA was higher than the control group in 1-12 h. BALB/c mice were subcutaneously immunized with Rv2628 protein, the production of IFN-gamma and IL-4 in the spleen cells was determined by Sandwich ELISA, in the Rv2628 immunized group, the level of IFN-gamma was significantly higher than that of IL-4 (P < 0.000 1). It indicated the protein induced Th1-tendency immune responses. At the same time, Rv2628(11-30) peptide used as coating antigen, the murine serum antibody titer detected by indirect-ELISA was 1:1 600, which demonstrated that Rv2628 could also induce humoral immune responses. In summary, Rv2628 could induce specific pro-inflammatory cytokines, affectively induce strongly Th1-tendency immune response and humoral response, it could be a potential target for developing subunit vaccine against TB. In addition, it laid foundation for probing the cross-talk between M. tb and host.

[Immunobiologic characteristics of a recombinant Listeria monocytogenes expressing Mycobacterium tuberculosis antigens]

OBJECTIVE

Tuberculosis is a chronic infectious disease caused by Mycobacterium tuberculosis complex. Hence, novel vaccines against TB are urgently needed and important to the public health.

METHODS

Immunobiologic characteristics of a recombinant attenuated Listeria monocytogenes strain LMdeltahly: :Ag85b-esat-6 was evaluated.

RESULTS

LMdeltahly: :Ag85b-esat-6 had lost the hemolytic activity. It was completely cleared from the livers and spleens of mice 5 days after inoculation via intravenous route. Furthermore, the LD50 of the recombinant strain increased by 4 Logs comparing to that of the parent strain. Histopathology reveals no obvious pathological changes following administration of the recombinant strain to mice, indicating its safety. In addition, the potential protective immune response was evaluated on C57BL/6 mice via intravenous immunization route. The results indicate that the antigen delivered by the recombination LM could induce Th1 type immune response and elicit strong cytotoxic lymphocyte effect against Ag85B-ESAT-6.

CONCLUSION

Thus, LMdeltahly::Ag85b-esat-6 had high safety to mice, and could be used as a novel vaccines candidate for preventing tuberculosis.

The mineralized collagen for the reconstruction of intra-articular calcaneal fractures with trabecular defects

BACKGROUND

In cases of severe subversion of the morphology of calcaneal fractures with trabecular defects, bone graft is often necessary to provide a mechanical buttress. The mineralized collagen (MC) is a novel bone substitute that is developed by biomimetic synthesis strategy that mimics the extracellular matrix (ECM) of natural bone in structure and chemical composition. It can avoid donor site morbidity and complications associated with harvesting autologous bone graft.

OBJECTIVE

In this study, we conducted a retrospective matched-pair analysis to assess the clinical and radiological performances of MC as a bone graft substitute in intra-articular calcaneal fractures with trabecular defects.

METHODS

24 pairs of intra-articular calcaneal fractures with trabecular defects were treated with open reduction, internal fixation, and grafting either with MC or autograft. Patient demographics, medical history, and CT fracture classification were matched. Fractures were monitored 6 weeks, 12 weeks, 6 months, and 1 year postoperatively for healing and postoperative complications and results were analyzed.

RESULTS

All patients had follow-up at a minimum of 12 months after surgery with a mean follow-up time of 17 months. All fractures were healed; there were no significant differences in the meantime to union and clinical between the two groups. The radiographic evaluation confirmed that a significant improvement in the mean Böhler's angle, Gissane's angle and the calcaneus height was observed in all patients in both treatment groups. A total of 29% (7/24) of patients suffered from harvest-site morbidity at 12 months in the autograft group. In contrast, all patients were free from postoperative local complications in the iliac region and no patient developed adverse reactions attributable to MC in the MC group.

CONCLUSION

These results justify and favor the use of MC as a good autograft alternative in displaced intra-articular calcaneal fractures with trabecular defects.

Overexpression of potassium channel ether à go-go in human osteosarcoma

Human ether à go-go (hEAG) potassium channels are primarily expressed in brain but also frequently overexpressed in solid tumors, which could indicate their potential value for cancer diagnosis and therapy. hEAG1, one member of the hEAG subfamily, has been shown to play a role in neoplastic process. Here we report the expression of hEAG1 in human osteosarcoma detected by a new polyclonal antibody. The full-length hEAG1 cDNA was cloned from human osteosarcoma cell line MG63 by RT-PCR and expressed in Escherichia coli as His tagged protein. The 6His-hEAG1F protein was purified by nickel agarose and used as the antigen to immunize rabbits following standard protocols. The obtained antiserum could detect hEAG1 exogenously expressed in HEK 293 cells. Furthermore, the polyclonal antibody was used to evaluate hEAG1 expression in 42 human osteosarcoma specimens and 19 osteochondromas specimens by immunohistochemistry. hEAG1 was expressed in 71.4% (30/42) osteosarcoma, and 15.8% (3/19) osteochondromas. Moreover, statistical analysis revealed that hEAG1 expression was not dependent on age, sex, site, histology, grade and type in the osteosarcoma specimens. Our data provide evidence that hEAG1 is overexpressed in human osteosarcoma and the hEAG1 polyclonal antibody offers a good tool for further characterization of the oncogenic function of hEAG1 in osteosarcoma.

Interpretation errors in CT angiography of the head and neck and the benefit of double reading

BACKGROUND AND PURPOSE

CTA provides high-resolution imaging of the head and neck vasculature but also of the soft tissues and bones. This results in a large volume of information to be interpreted. This study examines interpretation errors with head and neck CTAs and assesses whether double reading reduces miss rates.

MATERIALS AND METHODS

Consecutive CTAs of the neck and intracranial circulation were retrospectively identified and reviewed for vascular and nonvascular findings by a consensus of 2 neuroradiologists. The results were compared with the official report. Significant discrepancies were considered those that would have influenced follow-up or management.

RESULTS

We reviewed 503 studies; 144 were originally reported by a staff neuroradiologist alone, 209 by staff and diagnostic radiology resident, and 150 by staff and neuroradiology fellow. Twenty-six significant discrepancies were discovered in 20 studies, corresponding to 4.0% of studies with at least 1 miss, and an overall miss rate per study of 5.2%. There was at least 1 miss in 6.3% of studies interpreted by a staff neuroradiologist alone, 3.3% by staff and resident, and 2.7% by staff and fellow. The miss rate differences were not statistically significant. The most common misses were small aneurysms (50% of misses).

CONCLUSIONS

CTA neck and head datasets are now large, and there is a potential for missed findings. Significant discrepancies can occur with a low but not insignificant rate. Arterial pathology accounted for most discrepancies. This study emphasizes the need for careful systematic scrutiny for both vascular and nonvascular pathology regardless of indication. Double reading reduces error rates.

Tribological behavior of nanocrystalline nickel

During the last decade, an intensive investigative effort around the globe has been devoted to the understanding of scale effects on materials properties. In spite of their importance, nanoscale effects on tribological properties have attracted little attention. Such effects are of utmost importance to small scale devices such as nano and micro electromechanical systems that contain nanostructured dynamic components that would be difficult to replace or repair. The significant increase in strength arising from the grain size reduction in the nano domain is expected to impact on mechanical processes at asperity contacts that are dominating wear behavior. In the present work, nanocrystalline Ni produced by electroplating was used as a model system to study scale effects on tribological behavior. It was found that compared to bulk (microcrystalline), nanocrystalline Ni can cause a significant reduction in both, the coefficient of friction and wear rate. A consistent relationship was found between grain size, hardness and tribological behavior. It is suggested that the improved tribological behavior of the nanocrystalline Ni is due to the refinement of mechanical processes inhibiting plastic deformation by extensive dislocation motion leading to fracture events.

Estrogen receptor alpha genotype is associated with a reduced prevalence of radiographic hip osteoarthritis in elderly Caucasian women

PURPOSE

This study evaluated the association between polymorphisms in the estrogen receptor (ER) alpha gene (ESR1) and prevalent and incident radiographic hip osteoarthritis (RHOA) in a large, well-defined prospective cohort of elderly Caucasian women.

METHODS

Prevalent and incident RHOA was evaluated from all available pelvis X-rays obtained from the Study of Osteoporotic Fractures at baseline and after a mean of 8.3 years. Evaluable DNA samples were available from 4746 of these subjects. RHOA cases were defined by published methods. The ESR1 polymorphisms at intron I (Pvu II for a T/C substitution and Xba I for an A/G substitution) were genotyped in the context of a multiplex polymerase chain reaction (PCR) amplification followed by allele-specific single nucleotide polymorphism (SNP) detection with immobilized oligonucleotide probes in linear arrays. Multiple logistic regression was performed to estimate odds ratios (ORs) and 95% confidence intervals (95% CI) associated with the T/C and A/G polymorphisms.

RESULTS

RHOA was present in 12.1% of subjects, of whom 325 had joint space narrowing (JSN) score > or =3 and 130 had an osteophyte score > or =2 and JSN score > or =2. There was a significant reduction in the odds of prevalent RHOA for individuals with the C/C compared to T/T genotype at the Pvu II site with an OR of 0.71 (95% CI: 0.55-0.92) (P=0.01). Adjustments for age, weight, height, hip Bone mineral density (BMD) and estrogen use did not alter the relationship between the C/C genotype and reduced risk of RHOA, with an OR of 0.71 (95% CI: 0.54-0.94) (P=0.01). The risk of incident RHOA was reduced for the Pvu II C/C compared to the T/T genotype (P=0.11). Also, the reduced risk of incident RHOA in C/C subjects varied by estrogen use. There was no association between the Xba I G/G or G/A genotypes and RHOA with OR of 0.82 (95% CI: 0.61-1.10) (P=0.19) compared to women with A/A genotype.

CONCLUSIONS

We conclude that the C/C genotype of the ER alpha Pvu II polymorphism was associated with a modestly reduced risk of prevalent and incident RHOA in elderly Caucasian women. Additional work is required to understand how the intron I ESR1 polymorphism may alter joint degeneration.

Frizzled-related protein variants are risk factors for hip osteoarthritis

OBJECTIVE

To examine the association of the Arg200Trp and Arg324Gly variants of FRZB with the risk and phenotype of radiographic osteoarthritis (OA) of the hip and serum levels of Frizzled-related protein (FRP) in a prospective cohort of elderly Caucasian women.

METHODS

Radiographic hip OA status of patients was defined by the presence of severe joint space narrowing (JSN) (feature grade>or=3), a summary grade>or=3, or definite osteophytes (grade>or=2) and JSN (grade>or=2) in the same hip. Genotypes were obtained in 569 patients with radiographic OA of the hip and in 1,317 and 4,136 controls for the Arg200Trp and Arg324Gly variants, respectively. Serum FRP levels were measured by enzyme-linked immunosorbent assay. Multivariate logistic regression was performed.

RESULTS

The minor allele frequency for the Arg200Trp polymorphism was 0.12 in the control group compared with 0.14 in the group with radiographic OA of the hip (P=0.12), and the minor allele frequency for the Arg324Gly variant was 0.083 in the control group compared with 0.088 in the group with radiographic OA of the hip (P=0.63). The multilocus genotypes available in 1,886 subjects suggested that inheritance of both minor alleles was a risk factor for developing OA characterized by JSN (P<0.01). Patients with radiographic OA of the hip who were homozygous for the Arg200Trp minor allele had higher serum FRP levels than controls who were homozygous for the major allele.

CONCLUSION

Our data confirm findings of another study, that a rare haplotype with both Arg200Trp and Arg324Gly FRZB variants contributes to the genetic susceptibility to hip OA among Caucasian women, and that these polymorphisms may contribute to increased serum levels of proteins as biomarkers of OA.

Type I collagen α1 Sp1 transcription factor binding site polymorphism is associated with reduced risk of hip osteoarthritis defined by severe joint space narrowing in elderly women

OBJECTIVE

A common G/T substitution at an Sp1 binding site in intron 1 of the COL1A1 gene has been reported to be associated with reduced bone mineral density and increased risk of osteoporotic fracture. The purpose of this study was to examine whether there is an association between COL1A1 Sp1 polymorphism and radiographic osteoarthritis (OA) of the hip in elderly women in the Study of Osteoporotic Fractures.

METHODS

Radiographic hip OA status of subjects was defined by the presence of 1 of the following criteria in either hip: a joint space narrowing (JSN) score of >/=3, a Croft summary grade of >/=3, or both definite (score >/=2) osteophytes and JSN in the same hip. Cases of radiographic OA of the hip were further subdivided into those with JSN score >/=3 and those with a femoral osteophyte score >/=2 and JSN score </=2. The COL1A1 Sp1 polymorphism was genotyped using allele-specific kinetic polymerase chain reaction in 4,746 women. Multivariate logistic regression was performed to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

Radiographic OA of the hip was present in 571 women (12%). Of these patients, 325 (57%) had severe JSN (score >/=3), and 131 (23%) had moderate or moderate-to-severe femoral osteophytosis (score >/=2). There was no association of the T/T genotype with either radiographic hip OA or radiographic hip OA characterized by osteophytosis. For radiographic OA of the hip characterized by moderate-to-severe JSN, the odds of disease were significantly reduced among subjects with the T/T compared with the G/G genotype (OR 0.30, 95% CI 0.11-0.81, P = 0.02) and did not change after adjustment for potential confounders (OR 0.36, 95% CI 0.13-0.99, P = 0.048).

CONCLUSION

The T/T genotype of the COL1A1 Sp1 polymorphism was associated with a reduced risk of radiographic OA of the hip characterized by JSN. This association should be confirmed in other populations to determine if mechanistic studies are warranted.

Anti-infective reconstituted bone xenograft used for primary bone grafting to repair contaminated defect in the radius in dogs

OBJECTIVE

To investigate the effect of anti-infective reconstituted bone xenograft as a primary graft to repair a segmental with severe contamination.

METHODS

A canine model of contaminated defect of 1.5 cm in size in the radius was used, in which anti-infective reconstituted bone xenograft or reconstituted bone xenograft was implanted as a primary graft followed by internal fixation. The effectiveness of the two grafting materials in repairing a contaminated segmental defect was compared.

RESULTS

The animals which had received implant of anti-infective reconstituted bone xenograft should largely healed defects 6 months after operation while the defects implanted with reconstituted bone xenograft remained unrepaired with bone infection.

CONCLUSIONS

Besides its strong osteoinductive and osteoconductive activity, anti-infective reconstituted bone xenograft is highly antibacterial and can be used as a primary graft to repair the severely contaminated segmental defect.

The experimental study on the effect calcitonin gene-related peptide on bone resorption mediated by interleukin-1

To investigate the effect of calcitonin gene-related peptide (CGRP) on bone resorption mediated by interleukin-1 beta(IL-1 beta) in vitro, the osteoclasts isolated from the long bones of newborn SD rats were co-cultured with osteoblasts on ivory slices placed in 24-well plates. 24 h later, conditioned media containing CGRP and/or IL-1 beta were added to the wells respectively, and continued culturing for 48 h. After the cells were stripped off by ultrasonication, the ivory slices were stained in toludine blue. The number and the total area of resorption lacunae on each slice were measured by computer imaging analysis system. Our results showed that IL-1 beta significantly stimulated bone resorption, but CGRP inhibited the effect mediated by IL-1 beta in a dose-dependent manner. It is suggested that CGRP may inhibit osteoclastic bone resorption through two ways: One is that CGRP functions directly on osteoclasts to block their activation; the other is that CGRP regulates the release of cytokines by osteoblasts and indirectly affects the function of osteoclasts.