Application of magnetic carbon nanotube composite nanospheres in magnetic solid-phase extraction of trace perfluoroalkyl substances from environmental water samples.

The layer-by-layer assembly technique was used to synthesize novel multiwalled carbon nanotubes (MWCNTs) on magnetic carbon (Fe3O4@C) nanospheres, which were then used to extract six perfluoroalkyl substances (PFAS) in environmental real water samples using ultra high-performance liquid chromatography coupled to tandem mass spectrometry. The as-synthesized sorbent MWCNTs@Fe3O4@C was employed for magnetic solid-phase extraction (MSPE). The as-prepared MWCNTs@Fe3O4@C was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and vibrating sample magnetometer (VSM). The main extraction parameters were systematically optimized by Box-Behnken design. Under optimal conditions, excellent results were achieved. The synthesized sorbent showed wide linear ranges (0.1-1000 ng L-1), low detection limits (0.03-0.09 ng L-1) and good repeatability (3.80%-9.52%) for extracting and detecting six PFAS. The developed method was also applied to analyze six PFAS from environmental water samples. This study indicated that MWCNTs@Fe3O4@C composites are promising materials for the extraction and determination of PFAS from water samples.

Incidence tendency, etiological classification and outcome of congenital hypothyroidism in Guangzhou, China: an 11-year retrospective population-based study.

OBJECTIVES: An increased incidence of congenital hypothyroidism (CH) has been described worldwide over the years. In this study, we aimed to investigate the epidemiologic characteristics of CH, the iodine status in Guangzhou, China and to investigate which factors might influence the CH incidence during the period 2010-2020. METHODS: We retrospectively reviewed all cases of CH detected by newborn screening during the period 2010-2020. CH was classified as either suspected thyroid dyshormonogenesis (SDH) or thyroid dysgenesis (TD) based on thyroid ultrasound at first diagnosis. Patients were re-evaluated after 4 weeks of L-thyroxine withdrawal at age of 2-3 years to confirm the diagnosis of permanent CH (PCH) or transient CH (TCH). RESULTS: From 2010 to 2020, 1,655 patients with CH were confirmed from 2,400,383 newborns (1:1,450). The CH incidence increased from 1:2,584 in period [2010-2014] to 1:1,086 in period [2015-2020]. Among the 1,337 patients with thyroid ultrasound, 84.29% were SDH whereas 15.71% had TD. Further analysis revealed that more SDH (78.32%) were TCH whereas more TD (87.12%) turned to be PCH. The proportion of blood spot thyrotropin values >5 mIU/L ranged from 8.03 to 20.46%, indicating iodine deficiency. The prevalence of preterm infants increased from 5.50% in period [2010-2014] to 7.06% in period [2015-2020] (p<0.001). CONCLUSIONS: In the past decade, the CH incidence has increased progressively. SDH was the majority of CH, most of which were TCH, while most patients with TD were PCH. The increased incidence might be mainly due to iodine deficiency and increased rates of preterm infants in our study.

Same-sex twins have a high incidence of congenital hypothyroidism and a high probability to be missed at newborn screening.

BACKGROUND: We estimated the incidence of CH in twins, analyse the clinical features of CH cases in twins and further evaluate the CH screening strategy and recall procedures for twins. METHODS: A retrospective investigation of the screening results and confirmed cases in 724,791 newborns was conducted from 2015 to 2017 in Guangzhou. Clinical features were compared between twins with CH and singletons with CH. In addition, the twins were further divided into same-sex twins and different-sex twins to analyse the characteristics and incidence of CH and to compare differences in the confirmed cases in the 2 groups. RESULTS: The incidence of CH in same-sex twins was 1/593, which was much higher than the incidence of CH in singletons (1/1323) and different-sex twins (1/3060). Of the 20 twins diagnosed with CH, 17 were same-sex twins and 3 were different-sex twins. Among the six pairs of same-sex twins with CH, four had TSH inconsistency, which reached 67%. Eight of the 17 cases of same-sex twins diagnosed with CH had negative results at the first screening. CONCLUSIONS: Distinguishing same-sex twins from different-sex twins during newborn screening is more feasible. The incidence of CH in same-sex twins is much higher than that in the general population and the risk of transient CH is relatively high. In positive cases in same-sex twins, the simultaneous recall of the twin can effectively avoid a missed diagnosis. The screening center should properly evaluate the recall strategy and screening procedure for twins, especially twins of the same-sex.

Differences in anti-inflammatory effects between two specifications of Scutellariae Radix in LPS-induced macrophages in vitro.

Scutellariae Radix (SR), the root of Scutellaria baicalensis Georgi, is used as an antipyretic drug and has been demonstrated to have anti-inflammatory activity. SR is divided into two specifications, "Ku Qin" (KQ) and "Zi Qin" (ZQ), for use against different symptoms (upper energizer heat or lower portion of the triple energizer), according to the theory of traditional Chinese medicine (TCM). However, differences in the efficacies of these two specifications have not been determined. In the present study, we aimed to characterize the differences in the anti-inflammatory activities between KQ and ZQ and to explore how their differences are manifested in lipopolysaccharide (LPS)-induced macrophages. Our results showed that, in RAW264.7 cells (a mouse macrophage cell line derived from ascites), KQ and ZQ displayed anti-inflammatory effects by inhibiting the release of nitric oxide (NO), inducible NOS (iNOS), and nuclear factor-κB (NF-κB) in a dose-dependent manner without distinction. In NR8383 cells (a rat alveolar macrophage cell line), KQ and ZQ displayed similar effects on NO, iNOS, and NF-κB as seen in RAW264.7 cells, but KQ showed a higher inhibition rate for NO and iNOS than that shown by ZQ at the same concentration. These results indicated that there were differences in efficacy between KQ and ZQ in treating lung inflammation. Our findings provided an experimental evidence supporting the different uses of KQ and ZQ in clinic, as noted in ancient herbal records.

[Characteristics of DUOXA2 gene mutation in children with congenital hypothyroidism].

OBJECTIVE: To investigate the characteristics of DUOXA2 gene mutation and the genotype-phenotype relationship in children with congenital hypothyroidism (CH) in Guangzhou, China. METHODS: A total of 20 CH patients with suspected thyroid dyshormonogenesis who had no DUOX2 gene mutation were enrolled. These patients who were born between 2011 and 2012 were screened and diagnosed with CH in the Guangzhou Newborn Screening Center. PCR and direct sequencing were used to analyze DUOXA2 gene mutation. RESULTS: Among the 20 patients, 2 had p.Y246X/p.Y246X homozygous mutation; 4 had monoallelic heterozygous mutation, among whom 2 carried the known pathogenic mutation c.413-414insA, 1 carried p.Y246X, and 1 carried a novel mutation, p.G79R. Reevaluation was performed at the age of 2-3 years, and the results showed that the two patients with p.Y246X/p.Y246X homozygous mutation were manifested as transient and mild permanent CH, respectively. Among the four patients with monoallelic heterozygous mutation, the one who carried p.Y246X mutation was manifested as typical permanent CH, and the other three were manifested as transient CH. CONCLUSIONS: DUOXA2 gene mutation is a common molecular pathogenic basis for CH children with suspected thyroid dyshormonogenesis in Guangzhou, and most of them are manifested as transient CH. There is no association between DUOXA2 genotypes and phenotypes. The novel mutation p.G79R is probably a pathogenic mutation.

A modified acid-fast staining method for rapid detection of Mycobacterium tuberculosis.

A modified acid-fast staining method was developed for rapid detection of Mycobacterium tuberculosis and its L forms, wherein carbol fuchsin and dioxogen were mixed into the sputum smear. With this method, the dyeing time is shortened and heating is not required. The sensitivity, specificity, positive predictive value, negative predictive value, positive rate, and diagnostic efficiency of the new method were compared to those obtained by PCR using 50 clinical samples. Further, 468 clinical samples were analyzed using the new method, the modified intensified Kinyoun (IK) acid-fast staining method, and the traditional Ziehl-Neelsen acid-fast staining method. Differences among the positive detection rates of the three methods were analyzed using Student's t-test, and no significant differences were found between the new method and the modified IK acid-fast staining method, while the rates of both these methods were higher than that of the traditional acid-fast staining method. Additionally, the dyeing time in the new method was markedly less than that in the modified IK acid-fast staining method (5 min and 24 h, respectively).