Humans ; Gastrointestinal Microbiome ; Constipation/therapy* ; Probiotics/therapeutic use* ; Patients

OBJECTIVE To develop a high-throughput screening assay for the discovery of Omicron variant main protease(OM-Mpro) inhibitors based on the principle of fluorescence resonance energy transfer(FRET). METHODS The recombinant OM-Mpro enzyme was expressed in Escherichia coli Rosetta(DE3) cells, and further purified by a HisTrapTM chelating column. Subsequently, the enzymatic activity of OM-Mpro and wild type main protease(WT-Mpro) enzymes and inhibition of nirmatrelvir against both proteases were measured using FERT assay. With the FRET assay, OM-Mpro inhibitors were identified via high-throughput screening of an approved drug library. RESULTS The active OM-Mpro enzyme was successfully prepared from E. coli cells. OM-Mpro and WT-Mpro enzymes possessed the same enzymatic activity, and OM-Mpro remained susceptible to nirmatrelvir in vitro. Through high-throughput screening of the marketed drug library, it was found that cetylpyridinium chloride(CPC) is a mixed-type OM-Mpro inhibitor in vitro with an IC50 value of 8.76 μmol·L−1. CONCLUSION A robust FRET assay has been successfully developed based on the production of active OM-Mpro enzyme for screening of its inhibitors, and CPC is identified as a potential lead compound against OM-Mpro in vitro. This study provides a promising avenue for rapid discovery of broad-spectrum antivirals against coronavirus protease.

Objective:To explore the optimal index of rotational displacement of femoral neck fractures by modeling the axial rotational displacement of femoral neck fractures after reduction and based on X-ray projections.Methods:Six dry human femur specimens, comprising 2 males and 4 females, were utilized in the study. Design and manufacture a proximal femur ortholateral and oblique X-ray casting jigs and mounts. The femoral neck fracture was modeled on the femoral specimen, with Pauwells 30°, 50°, and 70° models (2 each) made according to Pauwells typing. The fractures were manually repositioned with residual anterior 20°, 40° and 60° axial rotational displacements. Each fracture model was projected at different angles (pedicled 40°, pedicled 20°, vertical 0°, cephalad 20°, and cephalad 40°), and the trabecular angle and Garden's alignment index of the model were measured to observe the imaging characteristics of the fracture line on the medial oblique and lateral oblique radiographs.Results:In the presence of a 20° and 40° anterior rotational displacement following reduction of a femoral neck fracture, the trabecular angle in the rotationally displaced group was not significantly different from that of the anatomically repositioned group in various projection positions. However, when a residual rotational displacement of 60° was present, the trabeculae appeared blurred at most projection angles in the Pauwells 30° and 50° models, failing to measure trabecular angles. In the Pauwells 70° fracture model, the trabecular angle in the rotational displacement group was significantly different from that in the anatomical reduction group. In anteroposterior radiographs, when the anterior rotation displacement was 60° in the Pauwells 70° group, Garden's contralateral index showed an unsatisfactory restoration (150°, 142°), whereas all rotationally displaced models in the Pauwells 30° and Pauwells 50° groups had a Garden's contralateral index of >155°, which achieved an acceptable restoration. In lateral radiographs, all rotational displacement models with Garden's alignment index>180° failed to achieve acceptable repositioning, and the larger the Pauwells angle the greater the Garden's alignment index at the same rotational displacement. In the internal oblique position with a bias towards the foot side, the image showed partial overlap between the femoral head and the shaft, making it difficult to assess the quality of the reduction. Conversely, when projected cephalad, the femoral neck appeared longer, particularly at a projection angle of 40° cephalad, allowing for clear observation of the fracture line and the anatomy of the proximal femur. The trabeculae were not well visualized in the external oblique position.Conclusion:There are limitations in applying the trabecular angle to assess the axial rotational displacement of the femoral head after reduction of femoral neck fractures. The Pauwells 70° with residual rotational anterior displacement of 60° was the only way to detect axial rotational displacement of the femoral head on anteroposterior radiographs Garden's alignment index. For the determination of axial rotational displacement of the femoral head, the Garden's alignment index on lateral radiographs provides higher reliability.

Examining mechanisms involved in the mutual regulation between the muscular system and the skeletal system, elucidating the key issues responsible for loss of muscle and bone mass and strength, and thus halting the progression of these conditions are critical measures for reducing fractures caused by falls and subsequent disability and mortality.At present, most studies have treated the muscular system and the skeletal system separately, often ignoring the mutual regulation and connections between them.This article reviews the current research progress on the mechanisms of interaction between the two systems, aiming to provide a basis for the prevention, diagnosis and treatment of disuse-related diseases in the elderly population.

Objective　To evaluate the sensitivity and specificity of the GenoType MTBDRplus V2.0 (Mycobacterium tuberculosis and resistance gene detection assay kit using PCR-linear probe hybridization with enzyme chromogenic method, referred to as MTBDRplus 2.0) kit for detection of rifampin and isoniazid resistance, providing the basis for improving the detection of drug-resistant Mycobacterium tuberculosis. Methods From January to December 2022, positive strains of Mycobacterium tuberculosis isolated and cultured from designated tuberculosis treatment hospitals in 32 counties (cities, districts) of Yunnan Province were collected. Resistance in 880 strains of Mycobacterium tuberculosis was detected by MTBDRplus 2.0, and the minimum inhibitory concentration (MIC) method was used for the drug sensitivity test. 　　　Results Using the MIC method as the gold standard, the sensitivity, specificity, positive predictive value, and negative predictive value of MTBDRplus 2.0 in detecting isoniazid resistance were 67.69%, 98.40%, 77.19%, and 97.45%, respectively. The consistency of the linear probe method and MIC method in detecting isoniazid resistance was moderate, with a Kappa value of 0.701 (P<0.001); the sensitivity, specificity, positive predictive value, and negative predictive values of MTBDRplus 2.0 in detecting rifampicin resistance were 87.80%, 99.40%, 87.80%, and 99.40%, respectively. The consistency of rifampicin resistance detection between MTBDRplus 2.0 and MIC method was relatively good, with a Kappa value of 0.872 (P<0.001). Among the 13 strains showing resistance to isoniazid with MTBDRplus 2.0, but sensitivity according to the MIC method, 11 strains (84.62%) had mutations in the inhA gene (C15T). Out of the 5 strains showing resistance to rifampicin with MTBDRplus 2.0, but sensitivity according to the MIC method, 4 strains (80.00%) had other mutations in the rpoB gene. Conclusions MTBDRplus 2.0 shows high sensitivity and specificity in detecting rifampicin resistance, but slightly low sensitivity in detecting isoniazid resistance. The low sensitivity in detecting isoniazid resistance may be due to insufficient target coverage of the detection kit. inhA gene mutations are poorly correlated with isoniazid resistance, and other mutations in the rpoB gene are poorly correlated with rifampicin resistance.

Sarcopenia, referred to as myopenia, is a systemic syndrome characterized by decreased muscle mass and muscle strength, and decline of motor function.The elderly are a high incidence group of myopenia.With the aging of the world's population becoming increasingly severe, the incidence rate of sarcopenia has also increased, which has brought a heavy burden to the elderly family and society, and has become an important social health problem for the elderly.At present, there are more and more researches on sarcopenia, but the pathogenic factors of sarcopenia are complex and diverse.The prevention and treatment of sarcopenia still need to be further explored and studied.The establishment of an ideal animal model is the key premise and basis for the related research of sarcopenia.In this paper, the different modeling methods, advantages and disadvantages as well as the scope of application of sarcopenia animal models are described, which can provide reference and help for the subsequent animal experimental research of sarcopenia.

Objective To investigate biomechanical characteristics of femoral neck fracture with different reduction qualities. Methods Three cases of Sawbones artificial femoral models were selected, and two cases of Pauwel III femoral neck fracture were modeled. Three cannulated screws were inserted into the models in the form of inverted triangle to fix the fracture. Two cases maintained different reduction qualities (defined as Model 1 and Model 2). In the 3 third case, no modeling operation was performed (defined as intact model). Then the strain gauges were respectively pasted on regions of interest of the 3 femoral models. Finally, the femur model was applied with the vertical load on mechanical testing machine. Results When the displacement of femoral head reached 4 mm, the average load of intact model, Model 1 and Model 2 was (236.30±5.35), (196.57±3.56), (69.50±2.95) N, showing significant differences. When the displacement of femoral head reached 5 mm, the average load of intact model, Model 1 and Model 2 was (276.7±3.40)，(232.93±2.64)，(80.83±4.54) N, showing significant differences. Conclusions The lower the reduction quality of the femoral neck fracture, the weaker the ability of the femur to bear stress, the higher the probability of nonunion, re-fracture and femoral head necrosis in the process of postoperative rehabilitation.

Post-stroke cognitive impairment (PSCI) is one of the common complications of stroke,which has a significant impact on the life of patients.Studies have shown that the incidence of PSCI varies from region to region,and is correlated with demographic and vascular risk factors,or is significantly different due to stroke types and characteristics.The specific mechanism of PSCI remains unclear,but early identification of its risk factors is helpful for early intervention.This article reviews the risk factors of PSCI.

Hypertension is one of the most important diseases that threaten human health, and has become a global problem. In recent years, the prevalence of hypertension in children has increased significantly year by year, and hypertension in children has a trajectory phenomenon, which is easy to cause cognitive damage and other target organ damage. Therefore, it is necessary to be alert and attached to the relationship between hypertension and cognitive impairment in children. This article reviews the epidemiological characteristics, etiology, diagnostic criteria of hypertension and pathophysiological mechanisms of cognitive impairment caused by hypertension in children.

Objective To study the association between impaired fasting glucose (IFG) and cognitive impairment in community elderly residents.Methods A total of ≥60 years old 1223 people were divided into normal fasting glucose (NFG) group (n=981) and IFG group (n=242).Their baseline data were recorded,their cognitive function was assessed according to the MMSE score.Results The education level,BMI,serum FBG,TG,LDL-C levels,incidence of hypertension and hyperlipidemia were significantly higher while the serum HDL-C level was significantly lower in IFG group than in NFG group (P＜0.05,P＜0.01).The incidence of cognitive impairment was significantly higher while the score of MMSE,orientation,attention and calculation,immediate recall and language was significantly lower in IFG group than in NFG group (40.50％ vs 21.51％,24.76±5.38 vs 26.60±4.26,9.07±1.81 vs 9.48±1.15,3.39±2.00 vs 3.88±1.81,2.93±0.41 vs 2.98±0.24,6.74±1.51 vs 7.18±1.15,P＜0.01).Age,female sex,LDL-C and IFG were risk factors for cognitive impairment in the elderly (P＜0.01,P＜0.05) while the education level was a protective factor for cognitive impairment in the elderly (P=0.000).Conclusion IFG is an independent risk factor for cognitive impairment in the elderly.Early diagnosis and intervention can improve cognitive function in the elderly.