The Analysis of Serum Klotho Protein Level and Related Gene Polymorphism in Osteoporotic Fracture of Elderly Patients with Osteoporosis.

Objective: Klotho protein level are reported to play important roles in the osteoporosis. To investigate the correlation between serum Klotho protein level and related gene (Klotho G395-A gene) polymorphism and osteoporotic fracture in elderly patients with osteoporosis. Methods: A total of 62 elderly patients with osteoporosis admitted to the Department of Orthopedics of our hospital from January 2021 to June 2022 were included in the study group. Another 62 elderly patients without osteoporosis who underwent a physical examination at the same time were selected as the control group. Patients in the study group were divided into group A (n = 23, osteoporotic fracture) and group B (n = 39, osteoporotic fracture) according to the occurrence of osteoporotic fracture. Serum Klotho protein level was detected in all patients, and its related gene (Klotho G395-A gene) polymorphism was analyzed. After fasting in the morning (fasting for more than 8 hours), 3-5 ml venous blood was collected and immediately placed in a centrifuge tube. Serum was separated and serum Klotho protein level was measured by enzyme-linked immunosorbent assay kit. Polymorphism typing was performed by Taqman allele-specific hybridization analysis. At the same time, general information (gender, age, body mass index, systolic blood pressure, diastolic blood pressure, glycated glucose protein, low-density lipoprotein cholesterol, bone mineral density) was collected. The differences in general data, serum Klotho protein level and Klotho G395-A gene polymorphism between the study group and the control group were analyzed. Spearman analysis was used to analyze the correlation between general data, serum Klotho protein level and Klotho G395-A gene and osteoporotic fracture. Logistic analysis was used to analyze the independent risk factors of osteoporotic fracture. Results: There was no significant difference of the sex, systolic blood pressure (SBP), diastolic blood pressure (DBP), Klotho G395-A genotype GG and alleles A and G between the study group and the control group. There was significant difference of body mass index (BMI), glycated glucose protein, low-density lipoprotein cholesterol (LDL-C), bone mineral density, serum Klotho protein level and Klotho G395-A genotype AA and AG were between the study group and the control group. Gender, age, glycated glucose protein and Klotho G395-A genotype AA were positively correlated with osteoporotic fracture (P < .05), while bone mineral density was negatively correlated with osteoporotic fracture (P < .05). There was no correlationship between the serum Klotho protein level and the incidence of osteoporotic fracture (P > .05). Logistic analysis showed that age, bone mineral density and Klotho G395-A genotype AA were independent risk factors for osteoporotic fracture. Conclusion: The level of serum Klotho protein and related gene polymorphisms are both related to osteoporotic fracture in elderly patients with osteoporosis. It is significant to reduce the incidence of osteoporotic fractures. In future, more experiments are needed to explore the underlying mechanism.

Enantioselective Fluorescence Recognition of Free α-Amino Acids by Ion-Type Ammonium Salt-Based Sensors.

Optically pure amino acids have extensive applications in pharmaceuticals, pesticides, food, materials, and other fields. Enantiomers recognition of chiral amino acids using optical methods with synthetic chiral sensors has attracted extensive attention. Most reported sensors typically identify guests by covalent or hydrogen bonding or hydrophobic interaction with amino acids and their derivatives. In this paper, a series of ion-type quaternary ammonium salt-based enantioselective fluorescent sensors were synthesized for chiral recognition of free α-amino acids via electrostatic interaction. The fluorescence intensity ratios ID/IL (ID, IL, fluorescence intensity of sensor when treated with D- or L-amino acid) were up to 2.1 and enantioselective fluorescence enhancement ratios ef (ef=[IL-I0]/[ID-I0] or [ID-I0]/[IL-I0]. (I0, fluorescence intensity of the sensor)) were up to 5.0. Among them, sensor 3 showed best enantioselective recognition performance toward tryptophan (Trp), and L-Trp significantly quenched the fluorescence of sensor 3, but D-Trp greatly enhanced the fluorescence of sensor 3, its ID/IL was 2.11 and ef was 1.8. The mechanistic investigation by NMR spectrum revealed that a tight three-point interaction, including electrostatic interaction, hydrogen bond, and π-π stacking, between sensor 3 and D-Trp was formed.

Direct Aerobic α-Hydroxylation of Arylacetates for the Synthesis of Mandelates.

Aerobic α-hydroxylation of α-methylene esters has proven challenging due to overoxidation and hydrolysis of the materials. In this article, KOtBu-promoted TBAB-catalyzed α-hydroxylation of α-methylene aryl esters using O2 as the oxygen source has been developed. Both low reaction temperature and catalyst TBAB are keys to success. This reaction provides an environmentally friendly and low-cost approach to mandelates, which are valuable building blocks and widely present in pharmaceuticals.

Copper(I)-Catalyzed Aerobic Oxidation of α-Diazoesters.

A practical Cu-catalyzed oxidation of α-diazoesters to α-ketoesters using molecular oxygen as an oxidant has been developed. Both electron-poor and electron-rich aryl α-diazoesters are suitable substrates and provide the α-ketoesters in good yields. In this oxidative system, α-diazo-ß-ketoesters are also compatible as substrates but unexpectedly furnish α-ketoesters via C-C bond cleavage, rather than the vicinal tricarbonyl products.

Oxidative α-Trichloromethylation of Tertiary Amines: An Entry to α-Amino Acid Esters.

α-Trichloromethylation of tertiary amines with trimethyl(trichloromethyl)silane by oxidative coupling, using DDQ as an oxidant, has been realized. The reaction is instantaneous, is scalable, and tolerates a broad range of functional groups and heteroarenes. The trichloromethylated products can be easily converted into ß,ß-dichloroamines, enamines, and α-amino acid esters under operationally simple conditions. This methodology provides an efficient alternative to the poisonous cyanation reactions for the synthesis of carboxylic acid and their derivatives.

Quantitative and In-Depth Survey of the Isotopic Abundance Distribution Errors in Shotgun Proteomics.

Accuracy is an important metric when mass spectrometry (MS) is used in large-scale quantitative proteomics research. For MS-based quantification by extracting ion chromatogram (XIC), both the mass and intensity dimensions must be accurate. Although much research has focused on mass accuracy in recent years, less attention has been paid to intensity errors. Here, we investigated signal intensity measurement errors systematically and quantitatively using the natural properties of isotopic distributions. First, we defined a normalized isotopic abundance error model and presented its merits and demerits. Second, a comprehensive survey of the isotopic abundance errors using data sets with increasing sample complexities and concentrations was performed. We examined parameters such as error distribution, relationships between signal intensities within one isotopic cluster, and correlations between different peak errors in isotopic profiles. Our data demonstrated that the high resolution MS platforms might also generate large isotopic intensity measurement errors (approximately 20%). Meanwhile, this error can be reduced to less than 5% using a novel correction algorithm, which is based on the theoretical isotopic abundance distribution. Finally, a nonlinear relationship was observed as the abundance error decreased in isotopic profiles with higher intensity. Our findings are expected to provide insight into isotopic abundance recalibration in quantitative proteomics.

Functional Proteomics Study Reveals SUMOylation of TFII-I is Involved in Liver Cancer Cell Proliferation.

SUMOylation has emerged as a new regulatory mechanism for proteins involved in multiple physiological and pathological processes. However, the detailed function of SUMOylation in liver cancer is still elusive. This study reveals that the SUMOylation-activating enzyme UBA2 is highly expressed in liver cancer cells and clinical samples. Silencing of UBA2 expression could to some extent suppress cell proliferation. To elucidate the function of UBA2, we used a large scale proteomics strategy to identify SUMOylation targets in HepG2 cells. We characterized 827 potential SUMO1-modified proteins that were not present in the control samples. These proteins were enriched in gene expression processes. Twelve candidates were validated as SUMO1-modified proteins by immunoprecipitation-Western blotting. We further characterized SUMOylated protein TFII-I that was identified in this study and determined that TFII-I was modified by SUMO1 at K221 and K240. PIAS4 was an E3 ligase for TFII-I SUMOylation, and SENP2 was responsible for deSUMOylating TFII-I in HepG2 cells. SUMOylation reduced TFII-I binding to its repressor HDAC3 and thus promoted its transcriptional activity. We further show that SUMOylation is critical for TFII-I to promote cell proliferation and colony formation. Our findings contribute to understanding the role of SUMOylation in liver cancer development.

Effects of haze particles and fog droplets on NLOS ultraviolet communication channels.

The performance of non-line-of-sight ultraviolet (UV) scattering communication depends largely on atmospheric parameters. In this paper, we consider haze, fog, two common types of aerosols, and introduce the density and size of aerosols as variables to study the channel path loss for the UV scattering communications. We modify a Monte-Carlo based multiple-scattering model and provide fitting functions to replace the complex calculations of Mie theory, which can be used to obtain the atmospheric coefficients and phase functions for the aerosols. Simulation results reveal that, given fixed elevation angles, the channel path loss is related to both communication range, the aerosol density, and size of aerosols. For a short communication range, an increase of aerosol density can reduce the path loss, which improves the performance of UV scattering communication. However, when the communication range is extended, the path loss will fall first and then rise with density of aerosols. This phenomenon also occurs for an increase of fog drop size. The density or size of aerosols that has the lowest path loss is inversely proportional to the communication range.

Copper-catalyzed aerobic autoxidation of N-hydroxycarbamates probed by mass spectrometry.

We present herein a mechanistic investigation by nanoelectrospray ionization mass spectrometry of copper-catalyzed aerobic oxidative processes involved in the N-nitrosocarbonyl aldol reaction of N-hydroxycarbamates. Protonated amine and copper as charge-tags aided the detection of reaction intermediates, which verified the enamine mechanism together with a competing enol process. Our experimental results reveal that the copper-catalyzed aerobic oxidation of N-hydroxycarbamates may proceed through an autoxidation catalytic mechanism in which a CbzNHO(.) radical abstracts a hydrogen from the bound N-hydroxycarbamate to release the nitroso intermediate through a bimolecular hydrogen-atom transfer. In this process, the chiral diamine also works as a ligand for copper to facilitate the aerobic oxidative step. The dual role of the chiral vicinal diamine as both an aminocatalyst and a bidentate ligand was finally uncovered.

Chiral Primary Amine/Palladium Dual Catalysis for Asymmetric Allylic Alkylation of ß-Ketocarbonyl Compounds with Allylic Alcohols.

An efficient dual catalytic system composed of a chiral primary amine and a palladium complex was developed to promote the direct asymmetric allylic alkylation (AAA) of ß-ketocarbonyl compounds. In particular, the synergistic dual catalytic system enabled the AAA reaction of challenging acyclic aliphatic ketones, such as ß-ketocarbonyl compounds and 1,3-diketones.

A proteomics strategy for the identification of FAT10-modified sites by mass spectrometry.

The ubiquitin-like protein FAT10 (HLA-F adjacent transcript 10) is uniquely expressed in mammals. The fat10 gene is encoded in the MHC class I locus in the human genome and is related to some specific processes, such as apoptosis, immune response, and cancer. However, biological knowledge of FAT10 is limited, owing to the lack of identification of its conjugates. FAT10 covalently modifies proteins in eukaryotes, but only a few substrates of FAT10 have been reported until now, and no FATylated sites have been identified. Here, we report the proteome-scale identification of FATylated proteins by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). We identified 175 proteins with high confidence as FATylated candidates. A total of 13 modified sites were identified for the first time by a modified search of the raw MS data. The modified sites were highly enriched with hydrophilic amino acids. Furthermore, the FATylation processes of hnRNP C2, PCNA, and PDIA3 were verified by a coimmunoprecipitation assay. We confirmed that most of the substrates were covalently attached to a FAT10 monomer. The functional distribution of the FAT10 targets suggests that FAT10 participates in various biological processes, such as translation, protein folding, RNA processing, and macromolecular complex assembly. These results should be very useful for investigating the biological functions of FAT10.

Asymmetric enamine catalysis with ß-ketoesters by chiral primary amine: divergent stereocontrol modes.

α-Branched ketones remain a challenging type of substrates in aminocatalysis due to their congested structures as well as the associated difficulties in controlling chemo- and stereoselectivity. In this work, we have explored asymmetric aminocatalysis with α-substituted ß-ketoesters. A simple chiral primary amine catalyst was identified to enable unprecedentedly effective catalysis of ß-ketoesters in α-hydrazination and Robinson annulation reaction with good yields and high enantioselectivities. Stoichiometric experiments with preformed enamine ester intermediates revealed their enamine-catalytic nature as well as the critical roles of acidic additives in facilitating catalytic turnovers and in tuning the chemo- and stereoselectivity. With the identical catalytic system, the two reactions demonstrated opposite chiral inductions in terms of the absolute configurations of the newly formed stereogenic centers. Investigations into this intriguing issue by DFT have revealed divergent stereocontrol modes. For α-hydrazination, H-bonding-directed facial attack determines the stereoselectivity, whereas a steric model is applied to the Robinson annulation where dual activations of both ß-ketoester and vinyl ketone/aldehyde are involved.

Merging aerobic oxidation and enamine catalysis in the asymmetric α-amination of ß-ketocarbonyls using N-hydroxycarbamates as nitrogen sources.

We describe herein an unprecedented asymmetric α-amination of ß-ketocarbonyls under aerobic conditions. The process is enabled by a simple chiral primary amine through the coupling of a catalytic enamine ester intermediate and a nitrosocarbonyl (generated in situ) derived from N-hydroxycarbamate. The reaction features high chemoselectivity and excellent enantioselectivity for a broad range of substrates.

An improved workflow for identifying ubiquitin/ubiquitin-like protein conjugation sites from tandem mass spectra.

The identification of ubiquitin (Ub) and Ub-like protein (Ubl) conjugation sites is important in understanding their roles in biological pathway regulations. However, unambiguously and sensitively identifying Ub/Ubl conjugation sites through high-throughput MS remains challenging. We introduce an improved workflow for identifying Ub/Ubl conjugation sites based on the ChopNSpice and X!Tandem software. ChopNSpice is modified to generate Ub/Ubl conjugation peptides in the form of a cross-link. A combinatorial FASTA database can be acquired using the modified ChopNSpice (MchopNSpice). The modified X!Tandem (UblSearch) introduces a new fragmentation model for the Ub/Ubl conjugation peptides to match unambiguously the MS/MS spectra with linear peptides or Ub/Ubl conjugation peptides using the combinatorial FASTA database. The novel workflow exhibited better performance in analyzing an Ub and Ubl spectral library and a large-scale Trypanosoma cruzi small Ub-related modifier dataset compared with the original ChopNSpice method. The proposed workflow is more suitable for processing large-scale MS datasets of Ub/Ubl modification. MchopNSpice and UblSearch are freely available under the GNU General Public License v3.0 at http://sourceforge.net/projects/maublsearch.

FTDR 2.0: a tool to achieve sub-ppm level recalibrated accuracy in routine LC-MS analysis.

Advances in proteomics research involve the use of high-precision and high-resolution mass spectrometry instruments. Although hardware improvements are the main impetus for the acquisition of high-quality data, enhancements in software tools are also needed. In this study, recalibration was verified as an important way to improve data accuracy. A new version tool, known as FTDR 2.0, was developed to recalibrate the mass-to-charge ratio error of most observed parent ions to the sub part per million level in routine experiments. First, many new parameters were introduced and screened as features online to reduce systematic error and to adapt to various data sets. Second, a support vector regression model was trained to characterize the complex nonlinear maps from features to mass-to-charge ratio measurement errors. Third, a specific mass-to-charge ratio error tolerance for each parent ion was estimated by considering the impact of signal intensity. FTDR 2.0 is a user-friendly tool that supports most commonly used data standards and formats. A C++ library and the source code are provided to support the redevelopment and integration into other mass spectrometry data processing tools. The performance of FTDR 2.0 was verified using several experimental data sets from different research programs. Recalibration with FTDR 2.0 has been proved to improve the peptide identification in qualitative, quantitative, and post-translational modification analyses.

Modified lateral approach combined with medial percutaneous approach versus triceps tongue-shaped flap approach and bilateral triceps brachii approach for pin fixation in treatment of irreducible displaced pediatric supracondylar humeral fractures.

To evaluate the clinical outcomes of the modified lateral approach combined with the medial percutaneous approach (MLACMPA) versus the triceps tongue-shaped flap approach (TTSFA) and the bilateral triceps brachii approach (BTBA) in the treatment of irreducible displaced supracondylar humeral fractures (SHFs) in children. Between March 2000 and July 2022, a total of 135 children who underwent open reduction and Kirschner wire cross internal fixation for irreducible displaced SHFs caused by trauma were retrospectively analyzed. According to the surgical approach, the patients were assigned to the TTSFA group (n = 36), the BTBA group (n = 40) and the MLACMPA group (n = 59). The duration of surgery, intraoperative blood loss, incision length, and elbow range of motion were compared. The 3 groups were similar in terms of mean age, sex distribution, and time from injury to operation. The duration of surgery, intraoperative blood loss, incision length and postoperative elbow range of motion in the MLACMPA group were significantly superior to those in the TTSFA group and BTBA group (P < .05). Compared the use of the TTSFA or the BTBA, using the MLACMPA for pin fixation in the treatment of irreducible displaced pediatric SHFs could significantly shorten the duration of surgery, reduce the operation trauma, facilitate earlier functional exercise of joints after operation and yield better elbow function.

LFQuant: a label-free fast quantitative analysis tool for high-resolution LC-MS/MS proteomics data.

Database searching based methods for label-free quantification aim to reconstruct the peptide extracted ion chromatogram based on the identification information, which can limit the search space and thus make the data processing much faster. The random effect of the MS/MS sampling can be remedied by cross-assignment among different runs. Here, we present a new label-free fast quantitative analysis tool, LFQuant, for high-resolution LC-MS/MS proteomics data based on database searching. It is designed to accept raw data in two common formats (mzXML and Thermo RAW), and database search results from mainstream tools (MASCOT, SEQUEST, and X!Tandem), as input data. LFQuant can handle large-scale label-free data with fractionation such as SDS-PAGE and 2D LC. It is easy to use and provides handy user interfaces for data loading, parameter setting, quantitative analysis, and quantitative data visualization. LFQuant was compared with two common quantification software packages, MaxQuant and IDEAL-Q, on the replication data set and the UPS1 standard data set. The results show that LFQuant performs better than them in terms of both precision and accuracy, and consumes significantly less processing time. LFQuant is freely available under the GNU General Public License v3.0 at http://sourceforge.net/projects/lfquant/.

(4RS)-Methyl 4-cyano-4-cyclo-hexyl-4-phenyl-butano-ate.

In the crystal structure of the title compound, C(18)H(23)NO(2), there are only van der Waals inter-actions present. The cyclo-hexyl ring has a chair conformation. The longer axes of the displacement parameters of the non-H atoms forming the ethyl-methyl-carboxyl-ate skeleton are perpendicular to the plane through the non-H atoms of this skeleton.

Differences and Correlations of Anxiety, Sleep Quality, and Pressure-Pain Threshold between Patients with Chronic Low Back Pain and Asymptomatic People.

Background: Chronic low back pain (CLBP) is a clinically common and expensive disease. Patients frequently take sick leaves because of pain and dysfunction, and their unpleasant life and work experiences cause psychological depression and anxiety and affect their quality of life. Sleep disturbance is a common problem among patients with low back pain (LBP) with more than 50% complaining about poor sleep quality. This study aimed to explore the correlations between anxiety, sleep quality, and pressure-pain threshold (PPT) and their differences between patients with CLBP and asymptomatic people. Methods: Forty patients with CLBP and 40 asymptomatic people were recruited. Relevant data, including State-Trait Anxiety Inventory, Pittsburgh Sleep Quality Index, and PPT, were individually and independently collected by blinded physiotherapists with a practicing certificate and then statistically analyzed. An independent sample t-test was used to determine the intergroup differences between patients with CLBP and asymptomatic populations. Pearson correlation coefficient was employed for correlation analysis. Results: The CLBP group had significantly higher anxiety scores (41.64 ± 9.88 vs. 36.69 ± 8.31; t = -2.496, p=0.015) than the asymptomatic group. A significant difference was found in the total score of the Pittsburgh Sleep Quality Index (6.41 ± 2.43 vs. 5.09 ± 2.18; t = -2.628, p=0.010) but not in the trait anxiety (44.00 ± 7.83 vs. 42.67 ± 9.51; t = -0.695, p=0.489) of the two groups. State-Trait Anxiety Inventory showed a low to moderate negative correlation with PPT. No remarkable correlation was observed between Pittsburgh Sleep Quality Index and PPT. Conclusions: Patients with CLBP showed considerably worse state anxiety and sleep quality than asymptomatic people; however, no substantial difference in PPT was found between the two groups. The results suggest that in clinical practice, the focus should include pain and related social and psychological factors. CLBP treatment could be considered from multiple perspectives and disciplines.This trial is registered with Chinese Clinical Trial Registry (Trial registration: ChiCTR-TRC-13003701).

Traditional Chinese Acupressure Massage of the Quadriceps Femoris Can Relieve Flexion Pain after Undergoing Total Knee Arthroplasty.

Objective: To reduce the pain of quadriceps during knee flexion after total knee arthroplasty and increase range motion of knee flexion. Design: Three-month prospective before/after quality improvement project. Setting. Department of Bone and Joint Surgery. Participants. A total of 80 patients who met the surgical indications were admitted to the outpatient department for surgery. They were randomly grouped by computer in advance, and the patients were divided into two groups according to the time of admission, each with 40 cases. Intervention. The intervention group performed routine rehabilitation exercises and received quadriceps acupoint massages for 20 minutes twice a day for two consecutive weeks. The control group performed routine rehabilitation exercises, such as gentle quadriceps massage for 20 minutes twice a day for two consecutive weeks. Main Outcome Measures. PPT (pressure pain threshold) of quadriceps femoris/VAS (visual analog scale) of knee flexion and motion of knee flexion. Results: The VAS score, range of motion, and tenderness threshold during flexion were significantly better in the intervention group than in the control group at 1, 2, and 4 weeks after surgery. But the VAS score, range of motion, and tenderness threshold did not significantly differ between groups at 12 weeks after surgery. Conclusion: Acupoint massage of the quadriceps femoris can relieve early flexion pain in patients after total knee arthroplasty. The trial was registered at clinical trials.gov.