PAC1 is the neuropeptide pituitary adenylate cyclase activating polypeptide (PACAP) preferring receptor, which belongs to class B G protein-coupled receptors (GPCR) family. PAC1 mediates the most effects of PACAP as neurotransmitter, neuroregulator and neuroprotectant, while its high expression has close relationship with some physiological and pathological processes such as nerve-injury and tumor. To further understand the function of PAC1, a cell line that expressed inducible PAC1 was constructed to achieve Doxycycline (Dox) dependent expression of PAC1 in CHO (Chinese hamster ovary) cell using the improved Tet (tetracycline)-on Advanced System. First, the PAC1-EYFP fusion gene composed of PAC1 gene and gene encoding EYFP (enhanced yellow fluorescent protein) was sub-cloned to the tetracycline response element pTRE-Tight vector to construct the recombinant vector pEYFP-PAC1-EYFP by double enzyme digestion. Second, the tetracycline regulation components pTet-On advanced vector and the response element pTRE-PAC1-EYFP vector were both introduced into CHO cells successively and the positive clones were screened with G418 and hygromycin respectively. Third, the controlled expression of PAC1-EYFP in CHO was induced by tetracycline analogues Dox in different concentrations and the different levels of receptor PAC1-EYFP were detected. The results of fluorescence analysis and western blotting show that the cell strain with Dox dependent expression of PAC1-EYFP named PAC1-Tet-CHO was obtained. Moreover, in PAC1-Tet-CHO cells the expression of PAC1-EYFP was induced by Dox in a dose-dependent manner. The inducible expression of PAC1 still was stable after sub-culturing for more than 10 passages. It was also found by MTT assay that the higher expression level of PAC1 endowed the cells with higher proliferative viabilities. The construction of controlled expression system of PAC1 will lay a foundation for the further research on PAC1 profiles.
Animals ; Blotting, Western ; CHO Cells ; Cloning, Molecular ; Cricetinae ; Cricetulus ; Genetic Vectors ; Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I ; biosynthesis

Objective:To investigate the clinical and genetic characteristics of Simpson-Golabi-Behmel syndrome (SGBS) type Ⅰ caused by glypican-3 ( GPC3) gene mutations. Methods:Data of one neonate with SGBS type Ⅰ from Shenzhen Maternity and Child Healthcare Hospital Affiliated to Southern Medical University was reviewed retrospectively. Literature was retrieved to summarize the clinical and genetic characteristics of SGBS type Ⅰ caused by GPC3 mutations, using terms of "Simpson-Golabi-Behmel type Ⅰ", "GPC3" and "glypican-3" from China National Knowledge Infrastructure, VIP database, Wanfang database, and PubMed from January 2010 till April 2021. Results:The male infant was admitted to the hospital at 4 h after birth due to "abdominal distension for 1 h", presenting with dysmorphic facial features, including macrocephaly, coarse face, broad nasal bridge, macrostomia, tongue with a groove in the middle, as well as macrosomatia, supernumerary nipples, and hypospadias. Whole exome sequencing revealed a novel frameshift mutation (c.720delC) in GPC3 gene of the patient and his mother for hemizygous and heterozygous variation, respectively, based on which SGBS type Ⅰwas confirmed. During the follow-up, overgrowth, neuroblastoma, and motor development retardation were found in the boy. In addition to the index patient, 92 cases of SGBS type Ⅰ reported in 31 articles were analyzed, including 89(95.7%) males and 4(4.3%) females. The main clinical features were craniofacial dysmorphism, pre/postnatal overgrowth with multiple congenital anomalies. Most patients were combined with language disorders, motor retardation, and various degrees of dysnoesia, and were more likely to develop embryonic tumors. Among the 93 cases, 11(11.8%) suffered from tumors. Apart from 21 cases of termination, 63 cases were born alive and nine cases died after birth. Pathogenic variants in GPC3 gene were reported in 80 cases, which were nonsense mutation in 25 cases (31.2%), DNA fragment deletion in 21 cases (26.2%), frameshift mutation in 16 cases (20.0%), large duplications in eight cases (10.0%), missense mutation in five cases(6.2%), and splice site mutation in five cases(6.2%). Conclusions:SGBS type Ⅰ is an X-linked recessive genetic disease with various phenotypes. Patients with postnatal craniofacial dysmorphism, overgrowth, and multiple congenital anomalies should be highly suspected of SGBS type Ⅰ. Genetic testing is conducive to its early diagnosis. Treatment requires multidisciplinary cooperation and long-term follow-up, especially for those with tumors.

Objective:To evaluate the efficacy and safety of hypomethylating agents (HMA) in patients with myelodysplastic syndromes (MDS) .Methods:A total of 409 MDS patients from 45 hospitals in Zhejiang province who received at least four consecutive cycles of HMA monotherapy as initial therapy were enrolled to evaluate the efficacy and safety of HMA. Mann-Whitney U or Chi-square tests were used to compare the differences in the clinical data. Logistic regression and Cox regression were used to analyze the factors affecting efficacy and survival. Kaplan-Meier was used for survival analysis. Results:Patients received HMA treatment for a median of 6 cycles (range, 4-25 cycles) . The complete remission (CR) rate was 33.98% and the overall response rate (ORR) was 77.02%. Multivariate analysis revealed that complex karyotype ( P=0.02, OR=0.39, 95% CI 0.18-0.84) was an independent favorable factor for CR rate. TP53 mutation ( P=0.02, OR=0.22, 95% CI 0.06-0.77) was a predictive factor for a higher ORR. The median OS for the HMA-treated patients was 25.67 (95% CI 21.14-30.19) months. HMA response ( P=0.036, HR=0.47, 95% CI 0.23-0.95) was an independent favorable prognostic factor, whereas complex karyotype ( P=0.024, HR=2.14, 95% CI 1.10-4.15) , leukemia transformation ( P<0.001, HR=2.839, 95% CI 1.64-4.92) , and TP53 mutation ( P=0.012, HR=2.19, 95% CI 1.19-4.07) were independent adverse prognostic factors. There was no significant difference in efficacy and survival between the reduced and standard doses of HMA. The CR rate and ORR of MDS patients treated with decitabine and azacitidine were not significantly different. The median OS of patients treated with decitabine was longer compared with that of patients treated with azacitidine (29.53 months vs 20.17 months, P=0.007) . The incidence of bone marrow suppression and pneumonia in the decitabine group was higher compared with that in the azacitidine group. Conclusion:Continuous and regular use of appropriate doses of hypomethylating agents may benefit MDS patients to the greatest extent if it is tolerated.

Objective To compare the detection results of three kinds of automated nucleic acid purifiers, and to evaluate the detection performance of the domestic 2019-nCoV RNA purifier. Methods Three automated nucleic acid purifiers, namely A (imported), B (domestic), and C (domestic) automated nucleic acid extraction instruments, were used to purify nucleic acid. The Conchestan 2019-nCoV RNA (Liquid) quality control product S5 (batch number 202007002, reference level 1000cp/ml) was chosen as the experimental object. The quality control product was diluted in a series of 10 to 1000 times to prepare experimental samples of different concentrations. Among them, the A nucleic acid purifier used its own matching reagents, and the B and C purifiers belonged to a same manufacturer with different models and used their own supporting reagents as well as third-party reagents, to evaluate the anti-pollution ability, precision, accuracy, repeatability, detection limit and linear correlation. Results Using the imported brand A as a reference standard for comparison, when using reagents from B, the linear correlation between the two domestic nucleic acid purifiers and the imported equipment were 0.999, 0.915 (N-terminal), and 0.997, 0.825 (ORF1ab-terminal), respectively; when using the third-patty reagents, the linear correlation between the two domestic nucleic acid purifiers and the imported equipment were 0.999, 0.915 (N-terminal) and 0.997, 0.825 (ORF1ab-terminal), respectively. Conclusion The extraction of 2019-NCOV RNA by domestic nucleic acid purifiers can be fully automated with good correlation. The system performance is comparable to international standards. Moreover, the extraction time of the domestic nucleic acid purifiers is shorter than the imported one, which offers obvious advantages when the number of samples is large.