Distribution characteristics of TiO2 NPs in Daihai lake and their stability regulated by abiotic factors.

Accurate detection and stability analysis of titanium dioxide (TiO2 NPs) in surface water are critical for ecological risk assessment. Quantitative analysis of TiO2 NPs in water and sediment of Daihai Lake was performed and their occurrence forms was characterized by TEM, XRD and FTIR. Further investigation into the impact of pH, ionic strength (IS) and dissolved organic matter (DOM) on the stability of TiO2 NPs was carried out, along with a correlation analysis between abiotic factors and TiO2 NPs concentration. Results showed that TiO2 NPs in water and sediment are 1.01 × 105 and 5.66 × 105 particles/mL in July 2023, respectively. After transformed in water sample from Daihai Lake, the hydrodynamic particle (HDD) of TiO2 NPs reach 600-700 nm, with reduced crystallinity and observable characteristic peaks of NaCl, which is related to the high concentration of NaCl in Daihai Lake. Structural defects and changes in surface properties of TiO2 NPs are introduced due to the adsorption of organic matter, leading to higher aggregation and sedimentation rates. Specifically, Ca2+ promote the sedimentation of TiO2 NPs more than Na+. Conversely, A/A0 increased to 0.80-0.94 from 0.64 after humic acid (HA) and fulvic acid (FA) added. Hydroxyl and carboxyl groups of FA enhanced steric hindrance and inhibited TiO2 NPs sedimentation. While a strong promotion effect on the sedimentation of TiO2 NPs is detected when 10 mmol/L Ca2+ coexisted with 10 mg/L HA, with 70% of the TiO2 NPs settled within 120 min. Additionally, the concentration of TiO2 NPs in Daihai Lake is significantly positively correlated with dissolved organic carbon (DOC) and humification index, which might be relate to the enhancement of TiO2 NPs stability of aromatic organic matter. And the high concentration of DOC will also lead to the stable existence of TiO2 NPs in water and exacerbate aquatic toxicity.

Comparison of the Diagnostic Performance of MeltPro and Next-Generation Sequencing in Determining Fluoroquinolone Resistance in Multidrug-Resistant Tuberculosis Isolates.

This study systematically investigated the performance of MeltPro and next-generation sequencing in the diagnosis of fluoroquinolone (FQ) resistance among multidrug-resistant tuberculosis patients and explored the relationship between nucleotide alteration and the level of phenotypic susceptibility to FQs. From March 2019 to June 2020, a feasibility and validation study with both MeltPro and next-generation sequencing was performed in 126 patients with multidrug-resistant tuberculosis. Using phenotypic drug susceptibility testing as the gold standard, 95.3% (82 of 86) of ofloxacin-resistant isolates were identified correctly by MeltPro. In addition, whole-genome sequencing was able to detect 83 phenotypically ofloxacin-resistant isolates. The isolates with an individual gyrB mutation outside the quinolone resistance-determining region (QRDR) had minimum inhibitory concentrations (MICs) of ≤2 µg/mL. Despite showing low MICs close to the breakpoint for isolates carrying only gyrA_Ala90Val, the combined mutation gyrB_Asp461Asn caused the ofloxacin MIC to be eight higher than that obtained in Mycobacterium tuberculosis (MTB) isolates with the Ala90Val mutation alone (median, 32 µg/mL; P = 0.038). Heteroresistance was observed in 12 of 88 isolates harboring mutations in the QRDRs. In conclusion, our data show that MeltPro and the whole-genome sequencing assay correctly can identify FQ resistance caused by mutations in the gyrA QRDR. The combined gyrB_Asp461Asn mutation may significantly decrease in vitro FQ susceptibility of MTB isolates with low-level-resistance-associated gyrA mutations.

Exploring profile and potential influencers of vaginal microbiome among asymptomatic pregnant Chinese women.

BACKGROUND: This study was designed to explore the profile and potential influencers of the vaginal microbiome (VMB) among asymptomatic pregnant Chinese women and its possible association with pregnancy outcomes. METHODS: A prospective study was conducted among pregnant Chinese women receiving regular prenatal care at a hospital in Shanghai, China from March 2017 to March 2018. Vaginal swabs were obtained from 113 asymptomatic pregnant women in mid-pregnancy and sequenced by the V3-V4 region of 16S rRNA on an Ion S5™ XL platform. Demographic characteristics and major pregnancy outcomes were collected through questionnaires and electronic medical records. RESULTS: The predominant vaginal community state types (CSTs) were CST I (45.1%) and CST III (31.9%). Participants were divided into a lactobacilli-dominant group (LD, CST I/II/III/I-III/V, n = 100, 88.5%) and a less lactobacilli-dominant group (LLD, CST IV-A/B, n = 13, 11.5%). Women in the LLD group showed an increased alpha diversity [median (interquartile range, IQR): 2.41 (1.67, 2.49) vs. 0.30 (0.17, 0.59), P < 0.001], which was related to a lower pre-pregnancy body mass index (BMI) (P = 0.012), and a greater instance of passive smoking (P = 0.033). The relative abundance of Lactobacillus was correlated positively with the pre-pregnancy BMI (r = 0.177, P = 0.041), but negatively with passive smoking (r =  - 0.204, P = 0.030). CONCLUSION: The vaginal flora of asymptomatic pregnant Chinese women was mostly dominated by Lactobacillus crispatus and L. iners. A lower BMI and greater instance of passive smoking may contribute to a less lactobacilli-dominant VMB. However, a larger sample size is needed.

[Determination of the allergic impurities in the parenteral injection of Chinese traditional medicines containing Salvia miltiorrhiza].

The residual protein mixture (the content is 4%, approximately), called Salvia miltiorrhiza antigen, was extracted from the Salvia miltiorrhiza cruel materials by mimicking the alcohol-deposit extracts process. Both rabbits and guinea pigs sensitized by Salvia miltiorrhiza could produce specified antibodies. Large molecular antigenic impurities were extracted from the Danshen injection and Xiangdan injection using the centrifugal filtering method. The test results of active systemic anaphylaxis (ASA) and passive cutaneous anaphylaxis (PCA) in guinea pigs confirmed that the extracted antigenic impurities could induce the anaphylaxis reaction in the animals which were sensitized by the Salvia miltiorrhiza antigen. Using the specified antibody produced from rabbits which were sensitiyed by Salvia miltiorrhiza, ELISA test method was developed to test the residual Salvia miltiorrhiza antigenic materials contained in the parenteral Chinese traditional medicines. Calculated as residual protein, the linear range was 0.08-5.12 microg x mL(-1) (r2 = 0.9906), the detection limit and quantization limit are 0.08 microg x mL(-1) and 0.4 microg x mL(-1), respectively. 308 batches of parenteral Chinese traditional medicines containing water-soluable components of Salvia miltiorrhiza were tested, and the Salvia miltiorrhiza antigenic impurities were spotted in 35 (11.4%) batches of samples. The test results show that the extracting process currently used can not remove the Salvia miltiorrhiza antigenic impurities completely, and this may be one of the reasons for anaphylactic reaction in clinics. The proposed ELISA method can be used for improving the manufacture process and for routine quality control of drug products.

Dispersity, mesoporous structure and particle size modulation of hollow mesoporous silica nanoparticles with excellent adsorption performance.

Hollow mesoporous silica nanoparticles (HMSNs) with different dispersities, mesoporous structures and particle sizes have been systematically synthesized by simply changing the octadecyltrimethoxysilane (C18TMS, mesopore-forming agent) percentage of the total silica sources over a wide range. The effects of the C18TMS percentage on the dispersity, mesoporous structure and particle size of HMSNs have been discussed in detail based on elaborate structure characterization. In addition, the volume of the core-etching agent and etching time have been adjusted carefully to further modulate the mesoporous structure of HMSNs. Encouragingly, the obtained HMSNs show excellent performance in removing organic pollutants with short equilibrium adsorption time, high adsorption capacity and outstanding recyclability. It is believed that these prepared HMSNs with different dispersities, mesoporous structures and particle sizes possess the potential to be used in many fields.

[Therapeutic effects of cannulated compression screws for treating femoral neck fractures].

OBJECTIVE: To explore the relevant factor of cannulated compression screws in treating femoral neck fractures. METHODS: From January 2004 to January 2011, 190 patients with femoral neck fractures treated by cannulated compression screws were analyzed retrospectively. In all of the 190 cases, there were 104 males and 86 females with an average of 65 years (ranged, 21 to 83 years). According to Garden classification system, 25 cases were type I, 51 cases were type II, 58 cases were type II and 56 cases were type IV. The time from injury to operation was 15 h to 10 d (mean 3.5 d). The gender,age, trauma type, fracture type, osteoporosis, emergency operation, fracture reduction, relation between open reduction and nonunion were observed and analyzed. RESULTS: All patients were followed-up for 12 to 84 months, with a mean of 38 months. All incisions obtained stage I healing. There were 23 patients with bone nonunion. The rate of nonunion was 12.1%. Single factor analysis showed that there were significant differences in age, trauma type, fracture type, fracture reduction and osteoporosis (P<0.05), but no meaning in gender, emergency operation, relation between open reduction and nonunion (P>0.05). CONCLUSION: Cannulated compression screws for femoral neck fractures can obtain good outcomes, and age, trauma type, fracture type, fracture reduction and osteoporosis are main factors.

[Surveillance of schistosomiasis in Hubei section of the Three Gorge Reservoir areas, 2007 - 2009].

The source of infection of schistosomiasis and snail situation in Hubei section of the Three Gorge Reservoir areas from 2007 to 2009 were investigated by combined epidemiological, immunological and field survey. The results showed that there were no local residents and livestock infected with shchistosome, and no Oncomelania snails were found, but 4 cases of imported patients with chronic schistosomiasis were checked out. It is suggested that the surveillance and intervention should be strengthened pointing to the risk of schistosomiasis transmission in the Three Gorge Reservoir areas, so as to prevent schistosomiasis being endemic in these areas.