High-throughput estimation of specific activities of enzyme/mutants in cell lysates through immunoturbidimetric assay of proteins.

High-throughput estimation of specific activities of an enzyme and its mutants in a group (enzyme/mutants) in cell lysates via high-throughput assay of their activities and separate immunoturbidimetric assay (ITA) of their proteins was proposed. Pseudomonas aeruginosa arylsulfatase (PAAS) and Bacillus fastidious uricase (BFU) served as two models. ITA employed 0.75 mg of antisera against PAAS or BFU as the reference in 96-well microplates to measure the difference of extinction at 340 and 700 nm. According to the calibration curve, ITA quantified the reference from 0.40 to about 2.4 µg. The consistency among the abundance of enzyme/mutants through ITA of proteins in cell lysates prepared under the same conditions supported their consistent immunological reactivity to the antisera. Specific activities of PAAS/mutants or BFU/mutants in cell lysates through ITA of proteins showed excellent proportionality to those carefully determined after purification. Receiver-operating-characteristic (ROC) analysis of specific activities through ITA of proteins gave a higher area-under-curve than those for ROC analyses of other activity indices, which allowed the recognition of a PAAS/mutant of 50% higher activity after cell amplification in high-throughput mode. Therefore, ITA of enzyme/mutants as proteins is promising to estimate their specific activities in cell lysates in high-throughput mode for quantitative comparison.

The effects of dual screen layout on neck-shoulder muscle activity and head-neck posture variability during computer tasks.

BACKGROUND: Larger dual screens have been widely used during office work and their biomechanical exposure should be explored. OBJECTIVE: To investigate the biomechanical effect of two dual screen layouts on neck-shoulder muscle activity and the variability of head-neck posture in computer users. METHODS: A preliminary study of the user-preferred dual screen angles was carried out in V-shaped and L-shaped layouts. Twenty healthy participants aged 19 to 26 years were recruited and assigned to perform reading, typing, and searching tasks for 30 minutes in both workstation layouts. Electromyography was measured at bilateral cervical erector spinae (CES), sternocleidomastoid (SCM), and upper trapezius (UT). The head-neck lateral bending, rotation, and flexion angles were recorded. The visual analog scale (VAS) was used to evaluate visual strain. RESULTS: The muscle activity at the left UT and right CES sites when using the V-shaped layout was significantly higher than the L-shaped. There were significant differences in head-neck rotation and flexion angles between the two layouts in reading and typing tasks. In the searching task, there was no significant difference in the head-neck rotation and flexion angles between the two layouts. The visual strain score was significantly higher in the V-shaped layout. CONCLUSION: The CES and UT muscles displayed higher levels of activation while using the V-shaped layout in comparison to the L-shaped layout. The head-neck rotation and flexion angles differed due to varied types of work when using V-shaped and L-shaped layouts.

The relationship between aquaporins and skin diseases.

Aquaporins (AQPs) are a family of transmembrane channel proteins that can rapidly transport water molecules. The main subtype expressed in the epidermis and dermis is AQP3. Studies have confirmed that AQPs exert certain physiological functions in the skin, such as the maintenance of normal shape, the regulation of body temperature, moisturization and hydration, anti-aging, damage repair and antigen presentation. The abnormal expression of AQPs in skin cells can lead to a variety of skin diseases. This review summarizes the relevance of AQPs in dermatophysiological and pathophysiological processes, highlighting their potential as new drug targets for the treatment of skin diseases.

Effects of Surgical Treatment Guided by the Three-Column Classification Method on Knee Joint Function and Postoperative Complications in Patients with Tibial Plateau Fractures.

Many patients with tibial plateau fractures present with various degrees of soft tissue contusion and severely damaged articular surface, ligament, and vascular nerves, and thus how to treat this kind of patient has become one of the great difficulties in clinical practice. Therefore, we aim to investigate the effects of surgical treatment guided by the three-column classification method on knee joint function and postoperative complications in patients with tibial plateau fractures. A total of 120 patients with three-column tibial plateau fractures admitted to our hospital from January 2018 to January 2019 were selected and divided into group A (n = 60) and group B (n = 60). Among them, the group A patients were treated with an anterior lateral approach in floating positions combined with reduction plate internal fixation with an L-shaped approach in the posteromedial joint, while the patients in group B received reduction plate internal fixation with a knee midline incision in supine positions. After that, the perioperative indexes, knee function scores, the MOS item short-from health survey (SF-36) scores, complication rate (CR), and overall treatment efficacy of the patients were compared between the two groups. The perioperative indexes in group A were significantly better than those in group B (P < 0.001); the knee function scores and SF-36 scores in group A were significantly higher than those in group B (P < 0.001); the CR in group A was significantly lower than that in group B (P < 0.001); the treatment efficacy in group A was significantly better than that in group B (P < 0.05). The three-column classification method, with highly instructive significance in tibial plateau fracture surgery, can improve treatment efficacy and reduce the incidence of complications, which is worthy of application and promotion in clinical practice.

In Hamstring Muscles of Patients With Knee Osteoarthritis an Increased Ultrasound Shear Modulus Indicates a Permanently Elevated Muscle Tonus.

BACKGROUND: Some patients with knee osteoarthritis (KOA) show pain, stiffness and limited flexion and extension at the back of the knee, leading to dysfunction and affecting life. This may be related to changes in the biomechanical properties of skeletal muscles. Shear wave elastography (SWE) can detect these changes by measuring muscle shear modulus. AIMS: To investigate hamstring muscle shear modulus of healthy people and patients was studied using SWE method, and the correlation analysis between the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score of patients' subjective feeling and shear modulus of objective quantification was conducted. METHODS: The hamstring shear modulus was measured by SWE in 50 patients and 50 healthy individuals. Pearson correlation coefficient was used to evaluate the correlation between hamstring stiffness and shear modulus in patients. RESULTS: The hamstring shear modulus were significantly higher in the KOA group [the semimembranosus (SM) 15.23 ± 7.23, the semitendinosus (ST) 15.94 ± 5.40, the biceps femoris long tendinitis (BFL) 14.21 ± 6.55] than in the control group (the SM 10.95 ± 2.41, the ST 11.25 ± 2.23, the BFL 9.98 ± 2.81) (p = 0.000, p = 0.000, p = 0.001). The hamstring shear modulus in the KOA group was moderately positively correlated with pain, shear modulus, and physical function score. CONCLUSION: Preliminary results show that the shear modulus of the hamstring of KOA patients is higher than that of healthy people, the WOMAC score and the shear modulus of patients are moderately correlated. These preliminary results show that ultrasonic shear wave elastography measurement of shear modulus may be enough to sensitive, can detect these effects, more targeted in order to assist the doctor's diagnosis and treatment.

Data for high-throughput estimation of specific activities of enzyme/mutants in cell lysates through immunoturbidimetric assay of proteins.

Data in this article are associated with the research article "Highthroughput estimation of specific activities of enzyme/mutants in cell lysates through immunoturbidimetric assay of proteins" (Yang et al., 2017) [1]. This article provided data on how to develop an immunoturbidimetric assay (ITA) of enzyme/mutants as proteins in cell lysates in high-throughput (HTP) mode together with HTP assay of their activities to derive their specific activities in cell lysates for comparison, with Pseudomonas aeruginosa arylsulfatase (PAAS) and Bacillus fastidious uricase (BFU) plus their mutants as models. Data were made publicly available for further analyses.

Polyclonal Antibodies in Microplates to Predict the Maximum Adsorption Activities of Enzyme/Mutants from Cell Lysates.

With microplate-immobilized polyclonal antibodies against a starting enzyme or its active mutant bearing consistent accessible epitopes, the maximum activity of an adsorbed enzyme/mutant (Vs) was predicted for comparison to recognize weakly-positive mutants. Rabbit antisera against Escherichia coli alkaline phosphatase (ECAP) were fractionated with 33% ammonium sulfate to yield crude polyclonal antibodies for conventional immobilization in 96-well microplates. The response curve of the activities of ECAP/mutant adsorbed by the immobilized polyclonal antibodies to protein quantities from a cell lysate was fit to an approximation model to predict Vs. With 0.4 µg crude polyclonal antibody for immobilization, Vs was consistent for ECAP in cell lysates bearing fourfold differences in its apparent specific activities when its abundance was greater than 0.9%. The ratio of Vs of the mutant R168K to that of ECAP was 1.5 ± 0.1 (n = 2), consistent with that of their specific activities after affinity purification. Unfortunately, the prediction of Vs with polyclonal antibodies that saturated microplate wells was ineffective to Pseudomonas aeruginosa arylsulfatase bearing less than 2% specific activity of ECAP. Therefore, with microplate-immobilized polyclonal antibodies to adsorb enzyme/mutants from cell lysates, high-throughput prediction of Vs was practical to recognize weakly-positive mutants of starting enzymes bearing fairly-high activities.

Approximated maximum adsorption of His-tagged enzyme/mutants on Ni2+-NTA for comparison of specific activities.

By approximating maximum activities of six-histidine (6His)-tagged enzyme/mutants adsorbed on Ni2+-NTA-magnetic-submicron-particle (Ni2+-NTA-MSP), a facile approach was tested for comparing enzyme specific activities in cell lysates. On a fixed quantity of Ni2+-NTA-MSP, the activity of an adsorbed 6His-tagged enzyme/mutant was measured via spectrophotometry; the activity after saturation adsorption (Vs) was predicted from response curve with quantities of total proteins from the same lysate as the predictor; Vs was equivalent of specific activity for comparison. This approach required abundance of a 6His-tagged enzyme/mutant over 3% among total proteins in lysate, an accurate series of quantities of total proteins from the same lysate, the largest activity generated by enzyme occupying over 85% binding sites on Ni2+-NTA-MSP and the minimum activity as absorbance change rates of 0.003 min(-1) for analysis. The prediction of Vs tolerated errors in concentrations of total proteins in lysates and was effective to 6His-tagged alkaline phosphatase and its 6His-tagged mutant in lysates. Notably, of those two 6His-tagged enzymes, Vs was effectively approximated with just one optimized quantity of lysates. Hence, this approach with Ni2+-NTA-MSP worked for comparison of specific activities of 6His-tagged enzyme/mutants in lysates when they had sufficient abundance among proteins and activities of adsorbed enzymes were measurable.