Hepatic stellate cells (HSCs) are the primary fibrogenic cells in the liver, and their activation plays a crucial role in the development and progression of hepatic fibrosis. Here, we report that retinoid X receptor-alpha (RXRα), a unique member of the nuclear receptor superfamily, is a key modulator of HSC activation and liver fibrosis. RXRα exerts its effects by modulating calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ)-mediated activation of AMP-activated protein kinase-alpha (AMPKα). In addition, we demonstrate that K-80003, which binds RXRα by a unique mechanism, effectively suppresses HSC activation, proliferation, and migration, thereby inhibiting liver fibrosis in the CCl₄ and amylin liver NASH (AMLN) diet animal models. The effect is mediated by AMPKα activation, promoting mitophagy in HSCs. Mechanistically, K-80003 activates AMPKα by inducing RXRα to form condensates with CaMKKβ and AMPKα via a two-phase process. The formation of RXRα condensates is driven by its N-terminal intrinsic disorder region and requires phosphorylation by CaMKKβ. Our results reveal a crucial role of RXRα in liver fibrosis regulation through modulating mitochondrial activities in HSCs. Furthermore, they suggest that K-80003 and related RXRα modulators hold promise as therapeutic agents for fibrosis-related diseases.

Objective To investigate the clinical manifestations,molecular genetics and gonadal pathol-ogy characteristics of patients with disorders of sex development(DSD),and to summarize the clinical experi-ence of identifying rare diseases from common symptoms.Methods The clinical data of 416 patients with DSD diagnosed and treated in the multidisciplinary center of DSD of Guangzhou Women and Children's Medical Cen-ter from May 2018 to August 2023 were retrospectively analyzed,summarized and discussed.Results Accord-ing to chromosome karyotype,416 cases of DSD were classified into three types:92 cases(22.1％)of abnormal sex chromosome karyotype,285 cases(68.5％)of 46,XY karyotype and 39 cases(9.4％)of 46,XX karyotype.Among the 92 patients with abnormal sex chromosome karyotype,59 cases were raised as males,18 cases(30.5％)complained of short penis with hypospadias and cryptorchidism.The most common karyotype was 45,X/46,XY(58 cases,63.0％).Among the 285 patients with 46,XY karyotype,238 cases were raised as males,and 63 cases(26.5％)complained of short penis and hypospadias;47 cases were raised as females,and 13 ca-ses(27.7％)complained of inguinal mass.A total of 216 patients with 46,XY karyotype were subjected to whole exome gene detection,and 155 cases(71.8％)were found to have molecular pathogenesis with the clinical phe-notype.Among the 39 patients with 46,XX karyotype,19 cases were raised as males,and 8 cases(42.1％)com-plained of short penis and hypospadias.In the 18 cases of gonad biopsy,17 cases showed testicular tissue in go-nads.Whole exome sequencing was performed in 14 cases.NR5A1 gene heterozygous mutation,SRY gene muta-tion and SOX3 gene mutation were found in 2 cases,respectively(14.3％).Twenty cases were raised as females,and 14 cases(70.0％)complained of clitoral hypertrophy.Gonad biopsy was performed in 8 cases,with 7 cases of ovotestis(87.5％)and 1 case of NR5A1 gene heterozygous mutation(14.3％).Conclusions The etiologies of DSD are complex and diverse,and the clinical manifestations are various,which can be manifested as hypospa-dias,micropenis,cryptorchidism and other common symptoms of the urinary system.Different etiologies have dif-ferent treatment options.Therefore,chromosome karyotype,molecular genetic testing and gonadal pathology can be used to clarify the cause of disease,especially for rare diseases,improve the detection rate,reduce the rate of missed diagnosis,and ensure reasonable treatment,especially sex selection.

Objective:To evaluate the activity of iduronate-2-sulfatase (IDS) in fetal villi and peripheral blood plasma of pregnant women at high risk of mucopolysaccharidosis type Ⅱ (MPS Ⅱ), and to discuss the application of gene analysis in prenatal diagnosis of MPS Ⅱ.Methods:The enzymatic testing and gene analysis results of 23 pregnant women at high risk of MPS Ⅱ, who underwent prenatal diagnosis in Guangzhou Women and Children′s Medical Center from February 2013 to December 2020, were analyzed retrospectively.The IDS activity in fetal villi (30 cases) and plasma (28 cases) was detected by artificial substrate fluorescence.The IDS activity in fetal villi (28 cases) and plasma (34 cases) of normal pregnant women was taken as control.Meanwhile, the fetal villi of both pregnant women at high risk of MPS Ⅱ and normal pregnant women were also analyzed by gene testing and for fetal sex identification.Data were compared between groups by the independent samples t test. Results:The normal reference values of the IDS activity in fetal villi and plasma of normal pregnant women were(71.2±23.4) nmol/(mg·4 h) and (611.1±114.5) nmol/(mL·4 h), respectively.Among the 30 cases of high-risk fetal villi, the IDS activity in fetal villi of 8 affected male fetuses was (1.7±0.3) nmol/(mg·4 h), which was significantly lower than that of 11 unaffected male fetuses (83.2±6.3) nmol/(mg·4 h) and that of 9 non-carrier female fetuses (80.0±7.5) nmol/(mg·4 h) ( t=10.8, 8.8; all P<0.01). Meanwhile, the IDS activity was measured in the maternal peripheral plasma of 28 pregnant women at high risk of MPS Ⅱ.Among them, the IDS activity in 8 affected male fetuses was(225.4±20.5) nmol/(mL·4 h), which was significantly lower than that in non-affected male fetuses[(451.0±15.1) nmol/(mL·4 h)] and that in non-carrier female fetuses[(467.7±45.3)nmol/(mL·4 h)]. Eight known pathogenic mutations were found in 30 cases at high risk of MPS Ⅱ of fetal villi, and the mutation types were c. 1048A>C, c.212G>A, c.514C>T, c.257C>T, c.425C>T, and c. 998C>T.Of the 8 cases, 6 affected male fetuses had significantly reduced IDS activities, and the other 2 female carriers had normal IDS enzyme activities. Conclusions:The IDS activity in fetal villi and peripheral plasma of pregnant woman is consistent with the gene analysis results.The IDS activity has an important reference value for the prenatal diagnosis of MPS Ⅱ in the first trimester.When no genetic mutations are found in the probands or the pathogenicity of the new mutation remains unclear, the IDS activity in fetal villi can be detected separately for the prenatal diagnosis of MPS Ⅱ.

Objective:To observe the efficacy of anti-sensitive moisturizing tolerance-extreme cream combined with isotretinoin in the treatment of severe acne.Methods:Fifty patients with severe acne were selected in the Dermatology Clinic of the Third People＇s Hospital of Hangzhou from November 2018 to July 2019. They were randomly divided into the experimental group of 25 cases and the control group of 25 cases. The experimental group was treated with anti-sensitive moisturizing tolerance-extreme cream combined with isotretinoin orally. The control group was treated with isotretinoin orally alone. Before and after treatment for 56 days, lactate score, skin cuticle hydration (SCH), transepidermal water loss (TEWL) and skin physiological indexes were measured.Results:After 56 days of treatment, the TEWL and SCH of the control group were 15.75±3.31 and 10.13±3.62, the TEWL and SCH of the experimental group were 12.17±3.61 and 28.07±3.17, respectively; the difference was statistically significant ( T was 3.610 and 12.398, P was 0.002 and 0.000, respectively). The volume and depth of cyst nodule, scar depression, skin roughness, absolute value and area of erythema in the experimental group were significantly lower than those in the control group ( T was 2.280, 1.676, 2.332, 1.508, 4.813 and 3.637; P was 0.031, 0.011, 0.027, 0.040, 0.000 and 0.001, respectively). Conclusions:Anti-sensitive moisturizing tolerance-extreme cream combined with isotretinoin has a good effect on severe acne and it can reduce the barrier damage and other adverse reactions.

Objectives:To explore the GAA varient spectrum and the genotype-phenotype correlations in patients with glycogen storage disease type Ⅱ (Pompe disease, PD), as well as to estimate the disease incidence based on carrier rate of GAA varients in Guangzhou population.Methods:A total of 57 PD cases were retrospectively enrolled at Guangzhou Women and Children′s Medical Center from January 1, 2010 to May 31, 2020. All patients presented symptoms before the age of 18 years. Each diagnosis was further confirmed by GAA enzyme activity and GAA variants. The carrier rate of GAA varients was calculated based on variants detected by whole exon sequencing among 2 395 healthy children in Guangzhou.Results:Among the 57 PD patients (including male 26, female 31),twenty-eight patients with infantile onset PD (IOPD) presented with progressive general muscle weakness and cardiomyopathy. The mean ages of symptom onset and diagnosis were (2.5±1.4) and (5.0±3.0) months, respectively. Twenty-six cases died in the first year after birth.Twenty-three patients with late onset PD (LOPD) presented with progressive muscle weakness. Seven of them had respiratory failure at diagnosis. The mean ages of symptom onset and diagnosis were (12.0±5.0) and (17.0±7.5) years, respectively. Six children with atypical IOPD showed motor delay, muscle weakness and cardiomyopathy. Their diagnosis was confirmed at 2.5-7.0 years of age. Among the 57 patients, 47 different variants were identified in the GAA gene. Three variants: c.797C>T, c.1109G>A and c.1757C>T were novel. c.1935C>A (25/114, 21.9%) and c.2238G>C (15/114, 13.2%) were the most common variants, detected in 57.1% of IOPD and 65.2% (15/23) of LOPD patients, respectively. Among the 28 IOPD patients, 26 cases (92.9%) carried at least one missense variant which indicated positive cross-reactive immunologic material (CRIM). The carrier rate of pathogenic variants in GAA gene among healthy children was 24/2 395. The estimated incidence of PD in this population is about 1/40 000. The frequencies of pseudodeficiency variants c.1726G>A and c.2065G>A homozygotes were 26.3% (15/57) and 35.1% (20/57) in PD patients, which were significantly higher than those (1.7% (40/2 395) and 3.9% (94/2 395)) in healthy children (χ2=151.2, 121.9; both P<0.01). Conclusions:PD presents as a spectrum, some as atypical IOPD. The c.1935C>A and c.2238G>C are common variants, correlated with IOPD and LOPD respectively. The c.796C>T and c.1082C>T are usually found in atypical IOPD. The majority of IOPD patients is predicted to be CRIM positive. The estimated incidence of PD is about 1/40 000.

Pectin methylesterase (PME) is an important pectinase that hydrolyzes methyl esters in pectin to release methanol and reduce the degree of methylation of pectin. At present, it has broad application prospects in food processing, tea beverage, paper making and other production processes. With the in-depth study of PME, the crystal structures with different sources have been reported. Analysis of these resolved crystal structures reveals that PME belongs to the right-hand parallel β-helix structure, and its catalytic residues are two aspartic acids and a glutamine, which play the role of general acid-base, nucleophile and stable intermediate, in the catalytic process. At the same time, the substrate specificity is analyzed to understand the recognition mechanism of the substrate and active sites. This paper systematically reviews these related aspects.
Carboxylic Ester Hydrolases ; chemistry ; metabolism ; Catalytic Domain ; Crystallography ; Pectins ; metabolism ; Protein Structure, Tertiary ; Substrate Specificity

Purpose: Progressive familial intrahepatic cholestasis (PFIC) is a rare genetic autosomal recessive disease caused by mutations in ATP8B1, ABCB11 or ABCB4. Mutational analysis of these genes is a reliable approach to identify the disorder. Methods: We collected and analyzed relevant data related to clinical diagnosis, biological investigation, and molecular determination in nine children carrying these gene mutations, who were from unrelated families in South China. Results: Of the nine patients (five males, four females) with PFIC, one case of PFIC1, four cases of PFIC2, and four cases of PFIC3 were diagnosed. Except in patient no. 8, jaundice and severe pruritus were the major clinical signs in all forms. γ-glutamyl transpeptidase was low in patients with PFIC1/PFIC2, and remained mildly elevated in patients with PFIC3. We identified 15 different mutations, including nine novel mutations (p.R470HfsX8, p.Q794X and p.I1170T of ABCB11 gene mutations, p.G319R, p.A1047P, p.G1074R, p.T830NfsX11, p.A1047PfsX8 and p.N1048TfsX of ABCB4 gene mutations) and six known mutations (p.G446R and p.F529del of ATP8B1 gene mutations, p.A588V, p.G1004D and p.R1057X of ABCB11 gene mutations, p.P479L of ABCB4 gene mutations). The results showed that compared with other regions, these three types of PFIC genes had different mutational spectrum in China. Conclusion The study expands the genotypic spectrum of PFIC. We identified nine novel mutations of PFIC and our findings could help in the diagnosis and treatment of this disease.

Objective:To evaluate and improve the performance of the newborn screening program for primary carnitine deficiency (PCD) based on tandem mass spectrometry and to investigate the incidence of PCD and molecular characteristics of SLC22A5 gene in Guangzhou.Methods:A total of 200 180 neonates born in Guangzhou from 2015 to 2019 were enrolled into the newborn screening program for PCD by tandem mass spectrometry at Guangzhou Newborn Screening Center. The positive results of screening for PCD was defined as free carnitine (C0) less than 10 μmol/L with decreased acylcarnitine species in dried blood spots of three to seven days after birth. Screen-positive newborns and their mothers were recalled for another blood spot sample. The diagnosis was confirmed based on decreased levels of C0 and acylcarnitine species in recalled blood spots and genetic analysis in SLC22A5 gene sequencing. The utility of using the sum of propionylcarnitine and palmitoylcarnitine (C3+C16) as a biomarker for acylcarnitine species in newborn screening was retrospectively evaluated. The levels of C0 and (C3+C16) at first screening were compared between newborns with PCD and newborns born to mothers with PCD by independent t test. The variant spectrum and known pathogenic variants carrier rate of SLC22A5 in 2 395 healthy children in Guangzhou Women and Children′s Medical Center through whole exon sequencing were analyzed. Results:Among 200 180 neonates, 239 (0.12%) cases were screen-positive for PCD. A total of 37 patients including 15 newborns and 22 mothers had confirmed PCD. The incidence of PCD was 1/13 345 in newborns and 1/9 099 in mothers, respectively. The positive predictive value of this program was 15.5%. Taking cutoff values of C0<8.5 μmol/L or C0 8.5~9.9 μmol/L with (C3+C16)<2 μmol/L, the number of screen-positive cases would be reduced from 810 to 224 without additional false negative case, when compared with cutoff value C0<10 μmol/L only. Both levels of C0 and (C3+C16) at first screening were not significant difference between newborns with PCD and newborns born to mothers with PCD ((6.2±2.4) vs. (5.0±1.8) μmol/L, (1.4±0.4) vs. (1.2±0.5) μmol/L, t=3.826, 0.326; P=0.058, 0.572). Seven PCD mothers experienced moderate fatigue and dizziness in the morning. One of them presented with cardiomyopathy in pregnancy. Genetic analysis of the SLC22A5 gene showed that p.S467C, p.F17L, p.R254X were the three most common variants in newborns with PCD. In PCD mothers and healthy children, the p.S467C, p.F17L and R399W were the three most common whereas the severe variant p.R254X was rare. The population carrier rate for pathogenic variants was 1 in 65 and the estimated incidence of PCD was about 1/16 500. Conclusions:Newborn screening can detect PCD both in newborns and mothers. Adding a quantitative biomarker (C3+C16) <2 μmol/L into the newborn screening program can improve the PCD screen performance. The severe variant p.R253X was common in PCD newborns but rare in PCD mothers and healthy children, indicating that the current screening program maybe failed to detect all PCD newborns and under-estimated the incidence rate of PCD in Guangzhou.

Objective To explore the characterization of thyroid stimulating hormone receptor(TSHR) gene mutational spectrum in children with hyperthyroidism from Guangzhou. Methods Ninety children were diagnosed with hyperthyroidism from July 2009 to July 2014 in our institute. Their median age at diagnosis was(7.5± 3.4) years, and there were 28 males and 62 females. Mutational analysis were performed by performing polymerase chain reaction (PCR) and DNA direct sequencing of exon 10 of TSHR gene. TSHR gene mutations from 50 unrelated healthy children were served as controls. The correlation between TSHR gene and hyperthyroidism in children was explored. Results A total of 3 mutations were identified in ninety children who were diagnosed with hyperthyroidism, one synonymous mutations(p.V614V), and two missense mutations( p. R707W and p. D727E). Mutation of p. V614V do not change amino acid and do not influence the structure and function of TSHR, no pathogenicity. p.R707W is a SNP associated with human cancers. The frequency of C allele of the D727E in children with hyperthyroidism was 86.7%, while 55.0% in the controls, significant different between the children with hyperthyroidism and the controls( P＜0. 01). In this study, a very high association between the D727E SNP and hyperthyroidism ( OR=18. 86, P＜0. 01) was found. Conclusion Three different mutations of TSHR gene exon 10 were identified in 90 children with hyperthyroidism, (c.1842A＞G,p.V614V、c.2119C＞T,p.R707W、c.2181G＞C,p.D727E), there were association between p.D727E and hyperthyroidism, nor p. V614V and p. R707W. Finally, p. D727E may be correlated with hyperthyroidism in children.