[Early effectiveness of local injection of multimodal drug cocktail during anterior cruciate ligament reconstruction and its influence on cartilage].

Objective: To explore the early effectiveness and influence on cartilage of local injection of multimodal drug cocktail (MDC) during anterior cruciate ligament reconstruction (ACLR). Methods: Between February 2022 and August 2023, patients undergone arthroscopic ACLR using autologous hamstring tendons were selected as the study subjects. Among them, 90 patients met the selection criteria and were randomly divided into 3 groups ( n=30) according to the different injection drugs after ligament reconstruction. There was no significant difference in baseline data such as gender, age, body mass index, surgical side, disease duration, preoperative thigh circumference, and preoperative levels of tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), IL-1, matrix metalloproteinase 3 (MMP-3), MMP-13, and aggrecan (ACAN) in synovial fluid between groups ( P>0.05). After the ligament reconstruction during operation, corresponding MDC (consisting of ropivacaine, tranexamic acid, and betamethasone in group A, and ropivacaine, betamethasone, and saline in group B) or saline (group C) were injected into the joint and tendon site, respectively. The length of hospital stay, postoperative tramadol injection volume, incidence of complications, degree of knee joint swelling and range of motion, visual analogue scale (VAS) score, International Knee Documentation Committee (IKDC) score, Lyshlom score, and Hospital for Special Surgery (HSS) score were recorded and compared between groups. The T2 * values in different cartilage regions were detected by MRI examination and the levels of TNF-α, IL-6, IL-1, MMP-3, MMP-13, and ACAN in synovial fluid were detected by ELISA method. Results: The patients in group A, B, and C were followed up (12.53±3.24), (13.14±2.87), and (12.82±3.32) months, respectively. All incisions healed by first intention. Compared with group C, group A and group B had shorter length of hospital stay, less tramadol injection volume, and lower incidence of complications, showing significant differences ( P<0.05); there was no significant difference between group A and group B ( P>0.05). The degree of knee swelling in group A was significantly less than that in group B and group C ( P<0.05), but there was no significant difference between group B and group C ( P>0.05). At 3, 6, 12, 24, and 48 hours after operation, VAS scores of group A and group B were significantly lower than those of group C ( P<0.05); at 72 hours after operation, there was no significant difference among the three groups ( P>0.05). At 3 days, 14 days, and 1 month after operation, the range of motion of knee joint in group A were significantly better than those in group C ( P<0.05), and there was no significant difference between the other groups ( P>0.05). At 1 month after operation, the IKDC score of group A and group B was significantly higher than that of group C ( P<0.05); there was no significant difference among the three groups at other time points ( P>0.05). There was no significant difference in Lyshlom score and HSS score among the three groups at each time point ( P>0.05). At 14 days after operation, the levels of IL-1 and IL-6 in the synovial fluid in groups A and B were significantly lower than those in group C ( P<0.05). There was no significant difference in the levels of TNF-α, MMP-3, MMP-13, and ACAN between groups A and B ( P>0.05). At 1 month after operation, there was no significant difference in the above indicators among the three groups ( P>0.05). At 3, 6, and 12 months after operation, there was no significant difference in the T2 * values of different cartilage regions among the three groups ( P>0.05). Conclusion: Injecting MDC (ropivacaine, tranexamic acid, betamethasone) into the joint and tendon site during ACLR can achieve good early effectiveness without significant impact on cartilage.

Dietary iron regulates intestinal goblet cell function and alleviates Salmonella typhimurium invasion in mice.

Iron is an important micronutrient that plays a vital role in host defenses and bacterial pathogenicity. As iron treatments increase the risk of infection by stimulating the growth and virulence of bacterial pathogens, their roles in anti-infection immunity have frequently been underestimated. To estimate whether adequate dietary iron intake would help defend against pathogenic bacterial infection, mice were fed iron-deficient (2 mg kg-1 feed), iron-sufficient (35 mg kg-1 feed), or iron-enriched diet (350 mg kg-1 feed) for 12 weeks, followed by oral infection with Salmonella typhimurium. Our results revealed that dietary iron intake improved mucus layer function and decelerated the invasion of the pathogenic bacteria, Salmonella typhimurium. Positive correlations between serum iron and the number of goblet cells and mucin2 were found in response to total iron intake in mice. Unabsorbed iron in the intestinal tract affected the gut microbiota composition, and the abundance of Bacteroidales, family Muribaculaceae, was positively correlated with their mucin2 expression. However, the results from antibiotic-treated mice showed that the dietary iron-regulated mucin layer function was not microbial-dependent. Furthermore, in vitro studies revealed that ferric citrate directly induced mucin2 expression and promoted the proliferation of goblet cells in both ileal and colonic organoids. Thus, dietary iron intake improves serum iron levels, regulates goblet cell regeneration and mucin layer function, and plays a positive role in the prevention of pathogenic bacteria.

Geographical origin traceability of rice using a FTIR-based metabolomics approach.

Infrared spectroscopy is a crucial tool to achieve the origin traceability of rice, but it is constrained by data mining. In this study, a novel infrared spectroscopy-based metabolomics analytical method was proposed to discriminate rice products from 14 Chinese cities by seeking 'wave number markers'. Principal component analysis (PCA), cluster analysis and orthogonal partial least squares discriminant analysis (OPLS-DA) were employed to separate all rice groups. The S-plot, permutation test and variable importance in projection (VIP) are used to screen eligible 'markers', which were further verified by a pairwise t-test. There are 55-265 'markers' picked out from 14 rice groups, with their characteristic wave number bands to be 2935.658-3238.482, 3851.846-4000.364, 3329.136-3518.160, 1062.778-1213.225, 1161.147-1386.819, 3348.425-3560.594, 3115.038-3624.245, 2567.254-2872.007, 3334.923-3560.594, 3282.845-3543.235, 3338.780-3518.160, 3197.977-3560.594, 3163.258-3267.414 and 3292.489-3477.655 cm-1, respectively. All but No. 5 rice groups show significantly low absorbance on their 'marker' bands. A mixed rice containing congenial No. 5 and No. 6 rice (80 : 20, m/m) was employed to test the validity of the method, and found that the 'marker' band of the mixed rice is the range of 1170.791-1338.598 cm-1, implying the existence of considerable discrepancy between the mixed rice and other rice. The results indicate that infrared spectroscopy coupled with metabolomics analysis is competent for origin traceability of rice; thus, it provides a novel and workable approach for the accurate and rapid discrimination of rice from different geographical origins, and a distinctive perspective of metabolomics to explore infrared spectroscopy and beyond, especially not confined in the field of origin traceability.

[Analysis of 29 fentanyl analogs and their fragmentation mechanism by liquid chromatography-quadrupole time-of-flight mass spectrometry].

Given the wide variety of fentanyl analogs, the test for this entire group tends to be crucial and particularly difficult since all fentanyl-like substances are listed as controlled substances in China. This study meticulously analyzed the fragmentation pathways and mechanisms of 29 fentanyl analogs and summarized the fragmentation pathways and features for the entire group of fentanyl analogs, thus providing a reference for related screening tests. Fentanyl, thiofentanyl, and sufentanil were selected as the representative compounds in this study, and the fragmentation mechanism of their fragment ions was interpreted. The general fragmentation rules for fentanyl analogs were summarized as well. The fragment ions of the three compounds formed by induced cleavage (i) came with high abundance ratios, such as fragment ions of m/z 188, 105, 194, 111, and 238, while the induced cleavage was due to the amide and piperidinyl groups. Moreover, the induction ability of amide group was significantly stronger than that of the piperidinyl group, and induced cleavage was the main fragmentation pathway for most of the fentanyl analogs. Furthermore, the fragment ions with m/z 281 and 287 for fentanyl and thiofentanyl were formed by loss of the propionyl group after single H rearrangement (rH). The fragment ions with m/z 216, 146, and 132 for fentanyl and thiofentanyl were formed by double H rearrangement (r2H). Although their abundance ratios were not high, they still had specificity and regularity. Elimination reaction (re) was also a very common fragmentation pathway for these compounds, leading to fragment ions with m/z 134 and 140. Phenylethyl substituents were more prone to the elimination reaction with a higher abundance ratio than thiophenethyl substituents. Compounds such as sufentanil with methoxy substituents at the piperidinyl para-position could produce a large number of fragment ions, which were more susceptible to the rH pathway and loss of methanol neutral molecules, leading to the formation of ions with m/z 355. Similarly, compounds such as remifentanil bearing a methyl formate substituent at the piperidine para-position also produced numerous fragment ions, which were more prone to the rH pathway to lose methyl formate or methanol neutral molecules and furnish fragment ions with m/z 317 or 345. Compounds containing hydroxyl substituents, such as ß-hydroxyfentanyl and ß-hydroxythiofentanyl, produce significant dehydration ions and formed fragment ions with m/z 335 (ß-hydroxyfentanyl) and m/z 341 (ß-hydroxythiofentanyl). A method based on liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) for the qualitative and quantitative determination of the 29 fentanyl analogs was developed. Drugs and white powder samples were extracted by acetonitrile, as well as protein and milk beverage samples. Sugar-containing solids or powders, drinking water, fruit and vegetable drinks, health drinks, tea drinks, and alcohol samples were extracted by 10% acetonitrile aqueous solution. Following vortexing, centrifugation, and membrane separation, the target compounds were separated on a Kinetex C18 column (100 mm×2.1 mm, 2.6 µm) with gradient elution at a flow rate of 0.4 mL/min. The mobile phases were composed of acetonitrile and 0.08% formic acid aqueous solution. The target compounds were quantified by LC-QTOF-MS using an external standard method in positive ion mode. The 29 fentanyl analogs showed good linear relationships in the range of 1-20 µg/L, and the correlation coefficients were greater than 0.995. The limits of detection (LODs) and limits of quantification (LOQs) were 0.01 mg/kg and 0.05, respectively. The average recoveries were 85.2%-112.9% for hypoglycemic drugs, Lulu drinks, glucose powder, Zhenlu health drink and chocolate, with RSDs of 1.9%-19.8% (n=6). This method is rapid, simple, time-saving, highly sensitivity and stable, and it is applicable to a wide variety of samples. Hence, it is suitable for the identification, confirmation, and quantitative detection of the 29 fentanyl analogs in drugs, solids or powders containing sugar, beverages, drinking water, wine samples, etc.

[Simultaneous determination of chromium speciation in cosmetics using reversed-phase ion-pair chromatography-inductively coupled plasma mass spectrometry].

A method was developed to determine chromium speciation simultaneously in cosmetics using reversed-phase ion-pair chromatography (RP-IPC) with inductively coupled plasma mass spectrometry (ICP-MS). After the extraction with disodium ethylenediaminetetraacetate(EDTA) in a water bath, the sample was separated on an XDB C18 column with the mobile phase of 5% (v/v) methanol-2. 0 mmol/L tetrabutylammonium (TBA) (pH 6.0), the flow rate of 1.0 mL/min and the injection volume of 100 microL. The collision cell technology was applied to eliminate the mass interferences of 40Ar12 C+ and 35 C16O1 H+ in the analysis of 52 Cr+. The separation was achieved within 5 min. The recoveries of Cr( III) and Cr( VI) ranged from 82.7% to 107. 2% with the relative standard deviations (RSDs) less than 5. 62% (n = 6) with the spiked amounts of 0.01 -0.50 microg in different kinds of cosmetic samples. The developed method has the advantages of simplicity, sensitivity and good reproducibility, and can be used for the simultaneous determination of Cr(III) and Cr( VI) in cosmetics.

[Determination of bifenthrin residue in plant-based foods using gas chromatography-mass spectrometry].

A method was established for the determination of bifenthrin residue in 8 plant-based foods using gas chromatography-mass spectrometry (GC-MS). The grain was extracted by acetonitrile and cleaned up with gel permeation chromatography (GPC) combined with a Florisil solid-phase extraction (SPE) cartridge, while the vegetables and fruits were extracted by ethyl acetate and cleaned up only with a Florisil SPE cartridge. Most of the lipids in the extract for the grain were eliminated by GPC, prior to SPE cleanup. The cleaned extract was analyzed by GC-MS with electron impact (EI) source in selective ion monitoring (SIM) mode. The detection limit was 5 microg/kg (S/N = 10). There was a good linearity within the range of 0.005 -0.5 mg/L with the correlation coefficient of 0.999 9. The recoveries were between 74% - 99% with the relative standard derivations of less than 13% at the spiking levels of 0.005, 0.04 and 0.1 mg/kg.

[Simultaneous determination of triazine herbicide residues in maize by gas chromatography].

A gas chromatographic method was developed for the determination of simeton, simazine, atrazine, propazine, terbumeton, terbuthylazine, cyprazine, simetryn, prometryn, terbutryn, methoprotryne, hexazinone residues in maize. The triazine herbicide residues were extracted with acetonitrile by blender and then cleaned up on a strong cation-exchange (SCX) solid-phase extraction cartridge. The SCX cartridge was conditioned with acetone, methylene chloride, washed with methylene chloride, acetone and eluted with methanol-water (9: 1, v/v) solution saturated potassium chloride. As a result, most interfering impurities were removed in the SPE cleanup procedure. The gas chromatographic analysis was performed on a capillary column (DB-5, 30 m x 0.25 mm i. d. x 0.25 microm) and determined by nitrogen phosphorus detector (NPD). Twelve triazine herbicides were effectively separated on this column. Diazinon was used as the internal standard for the determination. Linear correlation coefficients of the 12 herbicides were higher than 0.998 in the range of 0.01 to 2.0 mg/L. The limits of quantitation of the method were 0.01 mg/kg for these compounds. Average recoveries of these herbicides from spiked samples ranged from 84.0% to 106.8% at fortification levels of 0.01 - 0.5 mg/kg and the relative standard deviations (RSDs) were between 0.9% and 4.7%. The method is suitable for the simultaneous determination of a wide range of triazine herbicides in maize in commodities inspection.