Targeted long-read sequencing for comprehensive detection of CYP21A2 mutations in patients with 21-hydroxylase deficiency.

BACKGROUND: 21-Hydroxylase deficiency (21-OHD) is caused by pathogenic CYP21A2 variations. CYP21A2 is arranged in tandem with its highly homologous pseudogene CYP21A1P; therefore, it is prone to mismatch and rearrangement, producing different types of complex variations. There were few reports on using only one method to detect different CYP21A2 variants simultaneously. AIMS: Targeted long-read sequencing method was used to detect all types of CYP21A2 variants in a series of patients with 21-OHD. METHODS: A total of 59 patients with 21-OHD were enrolled from Peking Union Medical College Hospital. Long-range locus-specific PCR and long-read sequencing (LRS) were performed to detect the pathogenic variants in CYP21A2. RESULTS: Copy-number variants of CYP21A2 were found in 25.4% of patients, including 5.1% with 3 copies of CYP21A2, 16.9% with 1 copy of CYP21A2, and 3.4% with 0 copy of CYP21A2. The remaining 74.6% of patients had 2 copies of CYP21A2. Pathogenic variants were identified in all 121 alleles of 59 patients. Specifically, single-nucleotide variants and small insertions/deletions (< 50 bp) were detected in 79 alleles, of which conversed from CYP21A1P were detected in 63 alleles, and rare variants were found in the other 16 alleles. Large gene conversions (> 50 bp) from pseudogene were detected in 10 alleles, and different chimeric genes (CYP21A1P/CYP21A2 or TNXA/TNXB) formed by large deletions were detected in 32 alleles. Of all variants, p.I173N was the most common variant (19.0%). CONCLUSIONS: Our study demonstrated that targeted long-read sequencing is a comprehensive method for detecting CYP21A2 variations, which is helpful for genetic diagnosis in 21-OHD patients.

[Effect of growth hormone supplementation on liver and lung function in patients with hypopituitarism].

To analyze the clinical features of patients with anterior hypopituitarism (HP) complicated with cirrhosis, and to explore the effects of growth hormone supplementation on liver and lung function. A total of 11 patients with HP complicated with cirrhosis admitted to Peking Union Medical College Hospital from January 2016 to December 2022 were included in the study, including 8 males and 3 females, aged [M(Q1, Q3)]31 (20, 37) years. There were 6 patients with pituitary stalk interruption syndrome, 4 patients after craniopharyngioma resection, and 1 patient after germinal cell tumor chemoradiotherapy. Cirrhosis appeared at [M(Q1, Q3)]7 (1, 16) years after the diagnosis of HP. There were 7 cases complicated with hepatopulmonary syndrome (HPS). The liver and lung function of 5 patients were improved significantly after the addition of growth hormone, and the arterial partial pressure of oxygen increased from (47±11) mmHg(1 mmHg=0.133 kPa) to (84±12) mmHg. Timely supplementation of growth hormone can improve the symptoms of fatty liver, cirrhosis and HPS, and postpone or even avoid the transplantation of liver and other organs.

Comparing the efficacy of endovascular treatment for iliac vein compression syndrome with or without acute deep venous thrombosis: A single-center retrospective study.

BACKGROUND: To compare the efficacy of endovascular treatment for iliac vein compression syndrome (IVCS) with or without acute deep venous thrombosis of lower extremity. METHODS: This study retrospectively analyzed the clinical data of 300 IVCS patients, who received endovascular treatment between January 2013 and December 2017. According to whether IVCS was complicated by deep venous thrombosis or not, these patients were divided into non-thrombotic iliac vein lesion group (NIVL group, n = 127) and post-thrombotic iliac vein lesion group (PIVL group, n = 173). After endovascular treatment, all patients were followed up to assess the symptoms improvement and to evaluate the patency of iliac vein. RESULTS: The technical success rate was 98% (294/300), and percutaneous transluminal angioplasty with stenting was adopted in 294 cases. The incidence of perioperative complications was 36.33% (109/300), but no severe complications occurred. During a mean follow-up of 22.3 months (range 6-30 months), 9(6.82%, 9/132) patients in PIVL group had recurrence of deep venous thrombosis, but nobody had deep venous thrombosis and varicose veins recurrence in NIVL group. The effective rate of endovascular treatment in NIVL group and PIVL group was 96.88% and 90.15% (P = 0.050), while the cumulative primary patency of iliac vein in NIVL group was significantly higher than that in PIVL group (P = 0.008). CONCLUSIONS: The endovascular treatment is an effective, feasible, safe method for treating IVCS. There is no difference in the efficacy of IVCS patients with or without deep venous thrombosis, but the medium and long-term patency of patients with deep venous thrombosis is lower than that in patients without deep venous thrombosis.

[Clinical characteristics and molecular mechanisms of hypoparathyroidism related to GATA3 gene mutation].

Objective: To analyze the clinical characteristics and molecular mechanisms of 5 cases of hypoparathyroidism caused by GATA3 gene mutation. Methods: A total of 5 childhood-onset hypoparathyroidism patients with GATA3 mutation were identified from 198 hypoparathyroidism (aged ≤18 years) from 1975 to 2021 in Peking Union Medical College Hospital. Clinical data and biochemical indices of the 5 patients were collected and analyzed retrospectively. Genetic screening was conducted by targeted next-generation sequencing (T-NGS), and bioinformatics analysis was performed to analyze the underline mechanisms. Results: The medium onset age of hypoparathyroidism of the 5 patients was 0.5 (0.1, 1.3) years old, and the time duration from onset to confirmed diagnosis of hypoparathyroidism and hypoparathyroidism- deafness-renal dysplasia syndrome was (7.0±5.2) years and (15.0±5.4) years, respectively. The clinical manifestations included carpopedal spasm accompanied by seizures (5 cases), basal ganglia calcification (5 cases), cataract (1 case), deafness (4 cases), and renal malformations or absence (2 cases). The blood calcium and blood parathormone(PTH) before treatment was (1.65±0.31) mmol/L and (4.64±2.63) ng/L, respectively. The 5 patients carried different heterozygous mutations in GATA3 gene, which caused nonsense mutations, frameshift mutations and splice site mutations, respectively. All the GATA3 gene mutations of the 5 patients are classified as pathogenic or likely pathogenic by the Clin Var database and American College of Medical Genetics and Genomics(ACMG). Conclusions: Attention should be paid to genetic diseases in patients with childhood-onset hypoparathyroidism. The possibility of hypoparathyroidism-deafness-renal dysplasia syndrome should be considered in hypoparathyroidism patients with hearing loss or renal dysplasia. GATA3 gene screening is highly recommended for the confirmation of the diagnosis.

Safety and efficacy of common vitamin D supplementation in primary hyperparathyroidism and coexistent vitamin D deficiency and insufficiency: a systematic review and meta-analysis.

PURPOSE: Primary hyperparathyroidism (PHPT) is characterized by excessive secretion of parathyroid hormone (PTH). Vitamin D deficiency can stimulate parathyroid secretion. However, whether to correct vitamin D deficiency in patients with PHPT is controversial. We aimed to evaluate the safety and efficacy of vitamin D replacement in patients with PHPT. METHODS: We searched PubMed, Cochrane Library, and Embase. The relevant data were extracted from the included documents. The methodological items for non-randomized studies score entries were used for evaluation of quality. Review Manager 5.3 and Stata 12.0 were used for statistical analysis. RESULTS: A total of 11 articles were included with a total of 388 patients. The serum calcium mean difference (MD) was - 0.06 mg/dL [95% confidence interval (95% CI) - 0.16, 0.04]. Subgroup analysis showed that serum calcium levels did not change if the intervention time exceeded 1 month. The 24-h urinary calcium MD was 36.78 mg/day (95% CI - 37.15, 110.71), which indicated that there was no significant effect of vitamin D supplementation on 24-h urinary calcium levels. The MD of PTH was - 16.01 pg/mL (95% CI - 28.79, - 3.24). Subgroup analysis according to the intervention time showed that vitamin D intervention for more than 1 month significantly reduced PTH levels. The ALP MD was - 10.81 U/L (95% CI - 13.98, - 7.63), which indicated Vitamin D supplementation reduced its level. The MD of 25-hydroxyvitamin D was 22.09 µg/L (95% CI 15.01, 29.17), and no source of heterogeneity was found. CONCLUSION: Vitamin D supplementation in patients with PHPT and vitamin D deficiency significantly reduces PTH and ALP levels without causing hypercalcemia and hypercalciuria.

[Analysis of differences in clinical and biochemical characteristics and treatment effects in patients with different genotypes of Prader-Willi syndrome].

Objective: To analyze the differences in clinical and biochemical characteristics and treatment effects in patients with different genotypes of Prader-Willi syndrome (PWS). Methods: A total of 35 patients with PWS, 20 males and 15 females aged from 0.8 to 10.0 years with an average age of 3.0 years, were retrospectively included in this study. All of them were treated in the Department of Endocrinology of Peking Union Medical College Hospital from May 2017 to December 2018. The clinical material, biochemical data, and peripheral blood samples of the patients were collected. Genomic DNA was extracted from peripheral blood leukocytes of patients, and methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) was used to detect gene deletion or abnormal methylation. According to the results of detection, 35 patients were divided into two groups: paternal deletion group(n=27) and methylation abnormal group(n=8). The biochemical test results and the effect of growth hormone (GH) treatment of the two groups were analyzed. Results: MS-MLPA showed that 77% (27/35) of the patients were confirmed paternal deletion and 23% (8/35) were abnormal methylation. In terms of biochemical test results, the plasma concentrations of uric acid(UA) in the paternal deletion group were higher than that in the abnormal methylation group [(363±101) µmol/L vs (259±74) µ mol/L, P=0.019 ]. There is a linear relationship between body weight and uric acid level. After adjustment for weight., there was no significant difference in UA level between the two groups (P=0.101). Patients in both groups were treated with GH ((0.14±0.03) U/kg, QD). In paternal deletion group, patients were followed up for (26.0±13.6) months, and their height increased from (99.0±31.5) cm [(-0.3±1.1) SDS] to (107.5±27.0) cm [(0.7±0.9) SDS] (P=0.037). In the abnormal methylation group, patients were followed up for (25.8±11.6) months, and their height increased from (86.4±31.2) cm [(-0.7±1.8) SDS] to (95.6±26.5) cm [(0.0±1.6) SDS] (P=0.557). There was no significant difference in body mass index (BMI) between paternal deletion group and abnormal methylation group before and after treatment [(22.0±7.1) vs (22.4±6.8)] kg/m2, P=0.890;(17.0±3.1) vs (16.4±2.7) kg/m2, P=0.754]. Conclusions: There were no significant differences in biochemical test results between patients with paternal deletion and those with abnormal methylation. Early treatment with GH in PWS patients can effectively improve the increasing height and reduce excessive weight gain.

[Prevalence and related factors of dyslipidemia in patients with 21-hydroxylase deficiency].

Objective: To analyze the prevalence and the related factors of dyslipidemia in 21-hydroxylase deficiency (21-OHD) patients. Methods: A total of 205 patients with 21-OHD were recruited in Peking Union Medical College Hospital from January 2016 to January 2018. The basic information, glucocorticoid replacement therapy, and laboratory examination results of patients were obtained from medical records. The genotypes of CYP21A2 were identified by Sanger sequencing and multiplex ligation dependent probe amplification. The prevalence of dyslipidemia among 21-OHD patients, basic information and related hormone levels of 21-OHD patients with different status of blood lipid were described. Logistic regression model was used to analyze the related factors of dyslipidemia in 21-OHD patients. Results: The age of subjects was 17.0 (8.3, 25.0) years old, including 51 males (24.9%). According to CYP21A2 genotypes, there were 16 cases in Null group, 26 cases in Group A, 105 cases in group B, 27 cases in group C, and 31 cases in group D. The incidence of dyslipidemia was 29.3% (60/205), among which 37.3% (19/51) in male and 26.6% (41/154) in female patients, respectively. The M (Q1, Q3) of total cortisol level (nmol/L) and body mass index (kg/m2) of male 21-OHD patients with dyslipidemia were 0.17 (0.06, 0.35) and 25.76 (17.01, 30.45), respectively, which were higher than those with ortholiposis [0.04 (0.02, 0.21) and 18.83 (16.53, 23.88)] (all P<0.05). The M (Q1, Q3) of progesterone level (nmol/L), body mass index (kg/m2) and age (years) of female 21-OHD patients with dyslipidemia were 74.40 (50.97, 98.52), 23.09 (21.78, 27.78) and 23.00 (16.50, 28.00), respectively, which were higher than those with ortholiposis [52.81 (33.41, 68.85), 21.55 (18.63, 25.71) and 18.00 (9.50, 25.00)] (all P<0.05). The risk of dyslipidemia increased by 5.0% [OR (95%CI): 1.05 (1.01, 1.09)] for every 1 nmol/L increase of progesterone. Conclusion: The incidence of dyslipidemia is high in 21-OHD patients, and progesterone level is positively correlated with dyslipidemia.

Impaired geometry, volumetric density, and microstructure of cortical and trabecular bone assessed by HR-pQCT in both sporadic and MEN1-related primary hyperparathyroidism.

This study evaluated bone features of PHPT using HR-pQCT. The results showed both cortical and trabecular bones were significantly impaired in PHPT patients. Male and female PHPT patients suffered similar damages in bone. HR-pQCT indices were not observed to differ in MEN1 and sporadic PHPT patients. INTRODUCTION: High-resolution peripheral quantitative CT is a novel imaging technique used to separately assess trabecular and cortical bone status of the radius and tibia in vivo. Using HR-pQCT, we aimed to evaluate bone features of primary hyperparathyroidism patients in a Chinese population and reveal similarities and differences in bone features in multiple endocrine neoplasia type 1-related PHPT and sporadic PHPT patients in the Chinese population. METHODS: A case-control study was designed. In 58 PHPT patients and 58 sex- and age-matched healthy controls, the distal radius and tibia were scanned using HR-pQCT. Areal bone mineral density (aBMD) was also determined in PHPT patients using dual-energy X-ray absorptiometry (DXA). RESULTS: In comparison with controls, PHPT patients were observed to exhibit reduced volumetric BMD at the cortical and trabecular compartments, thinner cortices, and more widely spaced trabeculae. Significant differences were still observed when comparing data of female and male patients with age-matched controls separately. MHPT patients (n = 11) were found to have lower aBMD Z-scores in the lumbar spine, trochanteric region, and total hip compared with sporadic PHPT patients (n = 47), while no differences were observed in HR-pQCT indices between the two groups. In multiple linear regression models, no significant correlations were identified between PTH and HR-pQCT indices. However, height was found to positively correlate with HR-pQCT-derived trabecular indices at both the radius and tibia. CONCLUSIONS: PHPT affects geometry, volumetric density, and microstructure in both the cortical and trabecular bones in both male and female Chinese patients. MHPT patients were observed to have reduced aBMD as determined by DXA in the lumbar spine and hip in comparison with sporadic PHPT patients. However, HR-pQCT indices were not observed to differ.

Bone microstructure of adult patients with non-surgical hypoparathyroidism assessed by high-resolution peripheral quantitative computed tomography.

There is limited evidence regarding changes in bone microstructure in patients with hypoparathyroidism. In the current study, we used a non-invasive technique to assess bone structure in hypoparathyroidism patients and discovered site-specific changes which were mainly influenced by age and menstrual status. Such changes were more prominent in the trabeculae as well as in non-surgical as opposed to post-surgical patients. INTRODUCTION: Hypoparathyroidism (hypoPT) is a rare disease characterized by the lack of parathyroid hormone. There is limited evidence regarding changes in bone microstructure in patients with non-surgical hypoPT. We investigated bone microstructure of patients with non-surgical hypoPT using a non-invasive technique. METHODS: Patients with hypoPT were assessed using high-resolution peripheral quantitative computed tomography (HR-pQCT) and compared to age- and sex-matched healthy controls randomly selected from a pre-existing HR-pQCT database in a cross-sectional study. Preliminary comparison between patients with different etiologies of hypoPT was performed. Associations between bone microstructure and clinical parameters were investigated using correlation and regression analyses. RESULTS: A total of 94 patients with non-surgical hypoPT were recruited. Patients displayed an increase in trabecular volumetric BMD of the tibia (170.57 ± 34.32 vs. 156.48 ± 40.55 mg HA/cm3, p = 0.011) and increase in trabecular number of both the radius (1.48 ± 0.29 vs. 1.36 ± 0.22 mm-1, p = 0.003) and tibia (1.42 ± 0.23 vs. 1.24 ± 0.22 mm-1, p < 0.001) compared to healthy controls. Trabecular number was higher for non-surgical hypoPT compared to post-surgical hypoPT (1.37 ± 0.25 and 1.17 ± 0.13 mm-1, p = 0.022). Trends towards increase in cortical volumetric BMD were only present for post-menopausal female and male patients above the age of 50. For female patients, cortical volumetric BMD and area increased with age and decreased after menopause. For males, age had little influence on bone microstructure, but cortical porosity increased with longer treatment durations. CONCLUSIONS: Results from this pilot study suggested that both cortical and trabecular bone were altered in this group of patients with hypoPT. Etiology for hypoPT might influence bone microstructure, mainly on trabeculae. Age, menstrual status, and treatment duration were likely to influence bone microstructure in hypoPT.

Large Isospin Asymmetry in

ß-delayed one-proton emissions of ^{22}Si, the lightest nucleus with an isospin projection T_{z}=-3, are studied with a silicon array surrounded by high-purity germanium detectors. Properties of ß-decay branches and the reduced transition probabilities for the transitions to the low-lying states of ^{22}Al are determined. Compared to the mirror ß decay of ^{22}O, the largest value of mirror asymmetry in low-lying states by far, with δ=209(96), is found in the transition to the first 1^{+} excited state. Shell-model calculation with isospin-nonconserving forces, including the T=1, J=2, 3 interaction related to the s_{1/2} orbit that introduces explicitly the isospin-symmetry breaking force and describes the loosely bound nature of the wave functions of the s_{1/2} orbit, can reproduce the observed data well and consistently explain the observation that a large δ value occurs for the first but not for the second 1^{+} excited state of ^{22}Al. Our results, while supporting the proton-halo structure in ^{22}Al, might provide another means to identify halo nuclei.

[GNA11 gene rs11084997 polymorphisms might be associated with risk of adult-onset non-surgical hypoparathyroidism].

Objective: To investigate the association of GNA11 gene polymorphisms with the risk of adult-onset non-surgical hypoparathyroidism (Ns-HypoPT). Methods: Genotyping of GNA11 single nucleotide polymorphisms (SNPs) (rs28685098, rs4806907, rs11084997 and rs78003011) was carried out in 203 patients and 209 healthy participants by sequenom MassArray iPLEX System. These SNPs are located in promoter and 3'untranslated region (3'UTR) of GNA11 gene, respectively. Results: Allele and genotype frequencies of rs11084997 in patients were significantly different from those of controls (genotype GG:60.5% vs. 49.8%, GC: 35.5% vs. 41.6%, CC: 4.0% vs. 8.6%, P=0.038; G allele 78.3% vs. 70.6%, C allele 21.7% vs. 29.4%, P=0.012), and the C allele of rs11084997 carriers had a lower risk to develops Ns-HypoPT in additive and dominant genetic models [OR=0.382 (0.160-0.915), 0.647 (0.437-0.957)]. CC-Haplotype formed by the minor alleles of rs4806907 and rs11084997 was associated with a decreased risk of Ns-HypoPT in additive, dominant and recessive genetic model [OR=0.317 (0.126-0.801), 0.640 (0.430-0.952), 0.367 (0.148-0.912)]. Conclusion: The minor allele C of rs11084997 in GNA11 gene promoter was associated with decreased risk of Ns-HypoPT in Chinese population.

[Detection of CYP21A2 gene mutations and the differences in the levels of hormones in patients with 21-hydroxylase deficiency].

Objective: To analyze the detection of CYP21A2 gene mutations in 21-hydroxylase deficiency (21-OHD) patients, so as to determine the accuracy of clinical diagnosis. Methods: Totally, 514 patients with 21-OHD who visited Peking Union Medical College Hospital from January 2015 to January 2018 were enrolled and their clinical and biochemical data were collected. DNAs were extracted from peripheral blood leukocytes and CYP21A2 mutations were detected by Sanger sequencing and multiple ligation probe amplification (MLPA) technique. We divided 514 patients into three groups: two mutations of CYP21A2 alleles (group A), one mutation of CYP21A2 (group B), and no mutation of CYP21A2 (group C). Results: Mutation was detected in each allele of CYP21A2 gene in 401 (78.0%) patients, ninety (17.5%) had only one mutant allele and 23 (4.5%) had no mutation. There was no significant difference between the patients with different clinical phenotypes and the number of CYP21A2 gene mutations detected. In male, the cortisol of the patients with simple virilizing 21-OHD in group A [0.04 (0.02, 0.20) nmol/L] was lower than that of group B [0.24 (0.17, 0.28) nmol/L] and the difference was statistically significant (P=0.014). In female, 17-hydroxyprogesterone (17-OHP) of patients with salt wasting 21-OHD in group A [153.7 (90.1, 204.5) nmol/L] was higher than that of group B [38.2 (31.0, 183.3) nmol/L] and C [42.6 (27.8, 48.1) nmol/L] and the differences were statistically significant (both P<0.05). The progesterone of patients with simple virilizing 21-OHD in group C [23.0 (8.6, 33.2) nmol/L] was lower than that of gourp A [57.8 (34.4, 110.2) nmol/L] and B [63.6 (31.4, 110.8) nmol/L] and the difference were statistically significant (both P<0.05). The 17-OHP of patients with non-classical 21-OHD in group C [24.5 (20.4, 54.2) nmol/L] was lower than that of group A [158.7 (59.1, 187.6) nmol/L] and B [147.8 (131.9, 179.3) nmol/L]. The difference were statistically significant (both P<0.05). Conclusions: Mutations of two alleles have not been found in all patients with clinically diagnosed 21-OHD. Other congenital adrenal hyperplasia (CAH) types which can cause similar changes in 17-OHP and other hormones may be misdiagnosed as 21-OHD. Therefore, 21-OHD cannot be diagnosed with help of 17-OHP level only, and gene detection plays a vital role in the differential diagnosis of different CAH types.

[Clinical characteristics of testicular adrenal rest tumor and factors associated with its occurrence in 21-hydroxylase deficiency patients].

Objective: To analyze the occurrence and clinical characteristics of testicular adrenal rest tumor (TART) in 21-hydroxylase deficiency (21-OHD) patients, and further explore the possible factors related to the occurrence of TART. Methods: Twenty-seven male 21-OHD patients who visited Peking Union Medical College Hospital from January to December 2018 were enrolled and their clinical and biochemical data were collected. The CYP21A2 mutations were identified by Sanger sequencing and multiple ligation probe amplification (MLPA). Patients were divided into different subgroups according to the residual activity of 21-hydroxylase: Null (residual enzymatic activity 0, 3 cases), group A (0-<1%, 9 cases), group B (1%-5%, 7 cases), group C (20%-50%, 2 cases) and group D (6 cases). The ultrasound of testis was used to detect whether there was TART and its morphological characteristics. Results: Among 27 patients with 21-OHD [average age (17.4±9.3) years], 55.6% (15/27) had TART lesions, most of them were adolescents, and the youngest was only 4 years old. The lesions were mostly bilateral and hypoechoic. The levels of 17α-hydroxyprogesterone (17-OHP) and progesterone in patients with TART were higher than those in patients without TART [17-OHP: 199.6 (62.1, 232.7) nmol/L vs 7.4 (3.2, 105.0) nmol/L, P=0.003; progesterone: 97.1 (42.0, 126.8) nmol/L vs 5.4 (0.7, 20.0) nmol/L, P=0.004]. There was a correlation between the occurrence of TART and genotype of CYP21A2. Patients with Null and A genotypes were more likely to have TART than those with B and C genotypes (8/12 vs 4/9, P=0.021). Conclusions: TART is common in 21-OHD male patients, which is related to 17-OHP and CYP21A2 genotype. It is of great significance for the early screening of TART in 21-OHD patients.

[Determination of 1-methoxy-2-propanol in urine by headspace solid-phase microextraction coupled with gas chromatography].

Objective: To establish a method for the determination of 1-methoxy-2-propanol in urine using headspace solid phase micro-extraction coupled with gas chromatography. Methods: The 1-methoxy-2-propanol was enriched by headspace solid phase micro-extraction fiber coated with carbene/polydimethylsiloxane (CAR/PDMS) . Single factor rotation method was used to optimize the conditions of extraction temperature, salt amount, and extraction time. The separation was performed on DB-5 (30 m×0.32 mm×0.25 µm) capillary column and detected with flame ionization detector. The quantification was based on the standard curve. Results: The concentration of 1-methoxy-2-propanol in urine was linear in the range of 0.50-10.0 mg/L, and the linear correlation coefficient was 0.9993. The detection limit of the method was 0.14 mg/L, and the limit of quantification was 0.45 mg/L. The recovery was 85.8% to 104.7%, and the RSD of intra- and inter-batch precision were 3.25%-6.65% and 0.81%-3.96%, respectively. Conclusion: The method is high sensitivity and simple operation, and is suitable for the determination of 1-methoxy-2-propanol in urine of occupational exposure population.

[Determination of metabolites of styrene in urine by dispersive liquid-liquid microextraction coupled with high performance liquid chromatography].

Objective: To establish a method for the determination of mandelic acid and phenylglyoxylic acid in the urine of styrene by dispersive liquid-liquid microextraction-high coupled with high performance liquid chromatography. Methods: N-octanol was used as an extractant and ethanol was used as a dispersing agent. The phenylglycolic acid and phenylglyoxylic acid in the urine were extracted, and the upper liquid was taken after vortexing and centrifuged, and then was injected into HPLC for analysis. Results: The linear correlation coefficient of the concentration of phenylglycolic acid in the range of 0~10.0 mg/L was greater than 0.999. The detection limit of the method was 9.9 µg/L, the recovery rates were 86.1%~101.6%. The intraday RSDs of the method were 1.07%~3.76%, and the interday RSDs were 1.24%~3.33%. The linear correlation coefficient of phenylglyoxylic acid in the range of 0.0~2.0 mg/L is greater than 0.999. The detection limit of the method was 2.6 µg/L, the recovery rates were 88.8%~100.3%. The intraday RSDs of the method were 1.02%~ 3.17%, and the interday RSDs were 1.59%~2.41%. Conclusion: The method has low detection limit, high enrichment ratio and good sensitivity, and is suitable for determination of phenylglycolic acid and phenylglyoxylic acid in urine of occupational exposure to styrene.

Characterization of trehalose lipids produced by a unique environmental isolate bacterium Rhodococcus qingshengii strain FF.

AIMS: The aim of this study was to elucidate the chemical properties and applications of trehalose lipids produced by Rhodococcus qingshengii strain FF and optimize its production yield. METHODS AND RESULTS: Strain FF was identified as R. qingshengii. It was observed to produce biosurfactants in the presence of n-hexadecane. The biosurfactants were identified as the mixture of trehalose triesters and trehalose tetraesters, mainly consisting of TrehC12 C3 C6 C12 :10, TrehC11 C8 C6 :6, TrehC11 C6 C4 :5 and TrehC6 C4 C6 :5 based on the analysis of thin layer chromatography, Fourier transform infrared and flight tandem mass spectrometry. The best carbon source and nitrogen source for producing trehalose lipids was the mixture of n-hexadecane and oleic acid (m : m = 1 : 1) and the organic nitrogen, urea. Under this condition, the production of trehalose lipids could reach 7·97 g l-1 . The crude trehalose lipids showed extremely high surface-active properties and were proven to promote the degradation of naphthalene. CONCLUSIONS: The trehalose lipids produced by R. qingshengii strain FF exhibited high surfactant activity under various conditions and were proven to promote the degradation of naphthalene. SIGNIFICANCE AND IMPACT OF THE STUDY: Rhodococcus qingshengii strain FF is a potential candidate for bioremediation. The trehalose lipids might be used as unique biosurfactants in cosmetic industries, biological formulations and other applications.

[The value of (18)F-fluorodeoxyglucose positron emission tomography-computed tomography ((18)F-FDG PET-CT) in evaluating the stability of atherosclerotic plaques].

Objective: Positron emission tomography-computed tomography (PET-CT) has been used to quantify inflammatory response in the body. The aim of the present study was to explore the possibility of using this method to evaluate the stability of atherosclerotic plaques and the efficacy of atorvastatin in stabilizing atherosclerotic plaques. Methods: Twenty New Zealand male white rabbits were included and divided into the atorvastatin intervention group and the control group, with 10 rabbits in each group. Rabbits in both groups were fed with a high fat diet for 20 weeks, and treated with thoracoabdominal aortic balloon-pulling to establish atherosclerosis model at the end of the 2nd week. Rabbits in atorvastatin intervention group was given atorvastatin intragastrically once a day. At the 8th week, thoracoabdominal aortic ultrasound was used to detect plaques in all rabbits. Blood was drawn at the 3rd and the 20th week, respectively, to measure blood lipids, high-sensitive C-reactive protein (hs-CRP) and matrix metalloproteinase-9 (MMP-9). At the end of experiment, survival animals were scanned by (18)F-FDG PET-CT, and the average and maximum standard uptake values (SUVmean, SUVmax) of aortic segments were measured. Thereafter, the animals were sacrificed and aortic specimens of rabbits were taken and examined by immunohistochemistry. The pathological indexes were measured and compared. Results: At the end of experiment, the total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), hs-CRP [ (4.58±0.51) ng/ml vs.(5.87±0.66) ng/ml, P<0.01], MMP-9[ (43.93±2.16) ng/ml vs. (50.77±2.32) ng/ml, P<0.01], SUVmean (0.59±0.15 vs. 0.68±0.20, P<0.05) , SUVmax (0.68±0.20 vs. 0.81±0.27, P<0.05) , plaque area [ (0.36±0.24) mm(2) vs. (0.50±0.34) mm(2), P<0.05) ] and density of macrophage[ (4.34±1.54) % vs. (5.65±1.89) %, P<0.01] in the atorvastatin intervention group were significantly lower than those in the control group. In contrast, fiber cap thickness of the plaque[ (4.12±0.66) µm vs. (2.96±0.37) µm, P<0.01] in the atorvastatin intervention group was higher than that of the control group, and the difference was statistically significant. The arterial plaque areas were positively correlated with SUVmean (r=0.27, P<0.05) and SUVmax (r=0.43, P<0.01) . Fiber cap thickness was negatively correlated with SUVmean (r=-0.38, P<0.05) and SUVmax (r=-0.47, P<0.01) . The density of macrophage were positively correlated with SUVmean (r=0.52, P<0.01) and SUVmax (r=0.51, P<0.01) . Conclusion: (18)F-FDG PET/CT can be used to evaluate the efficacy of atorvastatin by the stability of atherosclerotic plaques.

[Molecular and clinical study on homozygous or heterozygous large deletion of CYP21A2 gene in 21-OHD patients].

Objective: To explore the relationship between homozygous or heterozygous large deletion of CYP21A2 gene and clinical manifestation in 21-hydroxylase deficiency (21-OHD) patients. Methods: The records of 100 patients with 21-OHD were collected between June 2016 and December 2017 in Peking Union Medical College Hospital. Large deletion of CYP21A2 gene was detected by multiplex ligation probe amplification (MLPA). The biochemical results and clinical symptoms of patients with homozygous or heterozygous large deletion were analyzed in order to investigate the influence of complete or single allele deletion of CYP21A2 gene on 21-OHD patients. Results: Large deletion of CYP21A2 gene was detected in 33 patients by MLPA, including 13 males and 20 females, with an median age of 10 (6,16) years. Two of them had simultaneous deletions of two alleles. Among 31 patients with heterozygous deletion, 16 were combined with gene mutations that severely affected 21-hydroxylase enzyme activity (I2G and Q318X), 15 with mutations that retained part enzyme activity (I172N and P30L). Two patients with complete deletion of CYP21A2 gene had no significant difference in biochemical and clinical manifestations compared with those with single allele deletion combined with another gene mutation that severely affected enzyme activity. Both kinds of patients above were manifested as severe salt-wasting type. Patients with a single allele deletion and a mutation retaining part enzyme activity were manifested as mild simple-viralizing type. Conclusion: Large deletion of CYP21A2 gene could appear in 21-OHD patients and the phenotype is similar to that of salt-wasting patients with heterozygous large deletion.

[Diagnostic value of multiplex ligation dependent probe amplification combined with Sanger sequencing in 21-hydroxylase deficiency].

Objective: To study the procedure of CYP21A2 gene mutation detection in 21-hydroxylase deficiency (21-OHD) patients. Methods: The detail clinical and biochemical data of 51 patients with 21-OHD [18 males and 33 females, with an average age of (16.4±9.9) years] were collected between December 2016 and December 2017 at Department of Endocrinology, Peking Union Medical College Hospital. Multiplex ligation dependent probe amplification (MLPA) and Sanger sequencing of the CYP21A2 gene were used to clarify the cause of 21-OHD. The genotype-phenotype correlation was also analyzed. Results: The incidences of large deletion, 8 bp deletion, I2G, I172N and F306+T were 19.6% (20/102), 1.0% (1/102), 30.4% (31/102), 25.5% (26/102) and 1.0%(1/102), respectively, and the detection rate of gene mutation in 51 21-OHD patients was 77.5% (79/102) by MLPA test. Except large and 8 bp deletion, all above mutations contained in MLPA and other 8 mutations, including P31L, Q319X, R361L, R357W, V282L, R484Q, G425S and R342W were detected, and the detection rate was 79.4% (81/102) by Sanger sequencing of CYP21A2. MLPA combined with direct sequencing identified mutations in all patients. Genotype correlated well with clinical phenotype in 21-OHD patients. Conclusions: When MLPA or CYP21A2 gene sequencing were used alone to diagnose the cause of 21-OHD, gene mutations in all patients could not be detected. The combination of the two methods can complement each other and fully clarify the underlying causes of 21-OHD.