[Evaluation of the efficacy of medial open wedge high tibial osteotomy combined with anterior cruciate ligament reconstruction in the treatment of varus knee osteoarthritis with anterior cruciate ligament injury]

Objective: To evaluate the efficacy of medial open wedge high tibial osteotomy (MOWHTO) combined with anterior cruciate ligament (ACL) reconstruction in the treatment of varus knee osteoarthritis (OA) with ACL injury. Methods: A follow-up study. The study retrospectively analyzed the patients underwent MOWHTO combined with ACL reconstruction for treatment of varus knee OA with ACL injury in Tianjin Hospital between April 2018 and September 2022. The preoperative and postoperative posterior slope angle (PSA), hip-knee-ankle angle (HKA), visual analog scale (VAS) pain scores, Lysholm score, International Knee Documentation Committee (IKDC) score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and Tegner score were compared. The follow-up indicators were recorded at 6 weeks, 3 months and 1 year after operation, and the complications were recorded. Results: The study included 32 patients (23 males, 9 females) with a mean age of (50.7±8.4) years. The mean follow-up time was (21.2±4.8) months. PSA increased from 9.2°±1.8° preoperatively to 11.1°±2.4° postoperatively, and HKA increased from 168.7°±2.2° to 181.5°±2.2° (both P<0.01). The indicators such as VAS score (6.8±1.1 vs 1.8±0.4), Lysholm score (52.6±7.1 vs 82.0±6.4), IKDC score (64.7±6.2 vs 80.3±10.0), WOMAC score (51.8±6.3 vs 81.8±6.5), and Tegner score (1.9±0.6 vs 5.0±1.0) were all improved after the operation (all P<0.01). Complications occurred in 5 patients (15.6%), including hematomas, sensory abnormalities, intermuscular vein thrombosis and correction angle loss. Conclusion: MOWHTO combined with ACL reconstruction is a safe and effective approach for the treatment of varus knee OA with ACL injury.

Protein Arginine Methyltransferase PRMT1 Is Essential for Palatogenesis

Cleft palate is among the most common birth defects. Currently, only 30% of cases have identified genetic causes, whereas the etiology of the majority remains to be discovered. We identified a new regulator of palate development, protein arginine methyltransferase 1 (PRMT1), and demonstrated that disruption of PRMT1 function in neural crest cells caused complete cleft palate and craniofacial malformations. PRMT1 is the most highly expressed of the protein arginine methyltransferases, enzymes responsible for methylation of arginine motifs on histone and nonhistone proteins. PRMT1 regulates signal transduction and transcriptional activity that affect multiple signal pathways crucial in craniofacial development, such as the BMP, TGFβ, and WNT pathways. We demonstrated that Wnt1-Cre;Prmt1 ^fl/fl mice displayed a decrease in palatal mesenchymal cell proliferation and failure of palatal shelves to reach the midline. Further analysis in signal pathways revealed that loss of Prmt1 in mutant mice decreased BMP signaling activation and reduced the deposition of H4R3me2a mark. Collectively, our study demonstrates that Prmt1 is crucial in palate development. Our study may facilitate the development of a better strategy to interrupt the formation of cleft palate through manipulation of PRMT1 activity.

Smad6 Methylation Represses NFκB Activation and Periodontal Inflammation

The balance between pro- and anti-inflammatory signals maintains tissue homeostasis and defines the outcome of chronic inflammatory diseases such as periodontitis, a condition that afflicts the tooth-supporting tissues and exerts an impact on systemic health. The induction of tissue inflammation relies heavily on Toll-like receptor (TLR) signaling, which drives a proinflammatory pathway through recruiting myeloid differentiation primary response gene 88 (MyD88) and activating nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB). TLR-induced production of proinflammatory cytokines and chemokines is reined in by anti-inflammatory cytokines, including the transforming growth factor β (TGFβ) family of cytokines. Although Smad6 is a key mediator of TGFβ-induced anti-inflammatory signaling, the exact mechanism by which TGFβ regulates TLR proinflammatory signaling in the periodontal tissue has not been addressed to date. In this study, we demonstrate for the first time that the ability of TGFβ to inhibit TLR-NFκB signaling is mediated by protein arginine methyltransferase 1 (PRMT1)-induced Smad6 methylation. Upon methylation, Smad6 recruited MyD88 and promoted MyD88 degradation, thereby inhibiting NFκB activation. Most important, Smad6 is expressed and methylated in the gingival epithelium, and PRMT1-Smad6 signaling promotes tissue homeostasis by limiting inflammation. Consistent with this, disturbance of Smad6 methylation exacerbates inflammation and bone loss in experimental periodontitis. The dissected mechanism is therapeutically important, as it highlights the manipulation of PRMT1-Smad6 signaling as a novel promising strategy to modulate the host immune response in periodontitis.

Osteoimmunology in orthodontic tooth movement

The skeletal and immune systems share a multitude of regulatory molecules, including cytokines, receptors, signaling molecules, and signaling transducers, thereby mutually influencing each other. In recent years, several novel insights have been attained that have enhanced our current understanding of the detailed mechanisms of osteoimmunology. In orthodontic tooth movement, immune responses mediated by periodontal tissue under mechanical force induce the generation of inflammatory responses with consequent alveolar bone resorption, and many regulators are involved in this process. In this review, we take a closer look at the cellular/molecular mechanisms and signaling involved in osteoimmunology and at relevant research progress in the context of the field of orthodontic tooth movement.

[Nondestructive quantitative analysis of Paracetamoli powder pharmaceutical by artificial neural network and near-infrared spectroscopy]

The application of artificial neural network for pharmaceutical nondestructive quantitative analysis were investigated. Real data set from near infrared reflectance spectra of Paracetamoli powder pharmaceutical were used to build up artificial network to predict unknown samples. The parameters affecting network were discussed. A new network evaluation criterion, the degree of approximation, was employed. Owing to good nonlinear multivariate calibration nature of ANN, the predicted results was reliable.

[A strain of influenza A H9N2 virus repeatedly isolated from human population in China]

OBJECTIVE

To understand the subtype of surface proteins (hemagglutinin and neuraminidase) and antigenic character of the isolate of influenza virus, as well as to know its origin.

METHODS

The virus isolation was performed on MDCK cells. The identification and antigenic analysis of the isolate were carried out with HI and NI tests. The serum antibody in population against the isolate was detected with HI and neutralization assays. The individual investigation of the patient from whom the H9N2 virus was isolated was followed.

RESULTS

The isolate was H9N2 subtype of influenza A virus. It was G9 like strain. Its antigenicity was different from that of H9N2 viruses which were previously found in humans, chickens and pigeons. The HI and neutralization titers to H9N2 virus in convalescent serum of the patient reached 1:400 and > or =1: 640, respectively. The HI antibody titer 1:25 to H9N2 virus was also detected in the serum of patient's mother.

CONCLUSIONS

The isolate is H9N2 subtype of influenza A virus and belongs to G9 like strain. The antigenic character of the isolate was different from that of H9N2 viruses found previously in humans, chickens and pigeons. The greatest possibility was that her mother had contacted with birds, especially chickens carrying H9N2 virus, then transmitted to her or she breathed in the air borne with H9N2 virus particles directly.

In-tube solid-phase microextraction coupled to capillary LC for carbamate analysis in water samples

Recently, the on-line sample preparation technique, intube solid-phase microextraction (SPME), was successfully implemented with a Hewlett-Packard 1100 HPLC system for analysis of carbamates in water samples. This paper describes the coupling of in-tube SPME to capillary LC and explores its utility as a sample preparation method in that format, relative to conventional LC. The Hewlett-Packard HPLC system was upgraded to a capillary LC system using commercially available accessories from LC Packings. The combination of in-tube SPME with a capillary LC system was expected to build on the merits of both in-tube SPME and the capillary LC to generate a sensitive method with an easy, effective, and efficient sample preparation. Due to the relatively large effective injection volume of the in-tube SPME technique (30-45 microL), on-column focusing was employed in order to achieve good chromatographic efficiency. Excellent sensitivity was achieved with very good method precision. For all carbamates studied, the RSD of retention time was between 0.5 and 0.8% under 4 microL/min microgradient conditions. The RSD of peak area counts was between 1.5 and 4.6%. The detection limits for all carbamates studied were less than 0.3 microg/L and, for carbaryl, just 0.02 microg/L (20 ppt). Compared with the conventional in-tube SPME/LC method, the LODs were lowered for carbaryl, propham, methiocarb, promecarb, chlorpropham, and barban, by factors of 24, 45, 42, 81, 62, and 56, respectively. The optimized method was successfully applied to the analysis of carbamates in surface water samples.

Automated in-tube solid-phase microextraction-high-performance liquid chromatography for carbamate pesticide analysis

In-tube solid-phase microextraction (SPME) is an automated version of SPME that can be easily coupled to a conventional HPLC autosampler for on-line sample preparation, separation and quantitation. It has been termed "in-tube" SPME because the extraction phase is coated inside a section of fused-silica tubing rather than coated on the surface of a fused-silica rod as in the conventional syringe-like SPME device. The new in-tube SPME technique has been demonstrated as a very efficient extraction method for the analysis of polar and thermally labile analytes. The in-tube SPME-HPLC method used with the FAMOS autosampler from LC Packings was developed for detecting polar carbamate pesticides in clean water samples. The main parameters relating to the extraction and desorption processes of in-tube SPME (selection of coatings, aspirate/dispense steps, selection of the desorption solvents, and the efficiency of desorption solvent, etc.) were investigated. The method was evaluated according to the reproducibility, linear range and limit of detection. This method is simple, effective, reproducible and sensitive. The relative standard deviation for all the carbamates investigated was between 1.7 and 5.3%. The method showed good linearity between 5 and 10000 microg/l with correlation coefficients between 0.9824 and 0.9995. For the carbamates studied, the limits of detection observed are lower than or similar to that of US Environmental Protection Agency or National Pesticide Survey methods. Detection of carbaryl present in clean water samples at 1 microg/l is possible.