Objective:Analysis of clustering characteristics of coronavirus disease 2019 (COVID-19) in Guangdong Province.Methods:The COVID-19 cases in Guangdong Province onset from January 1 to February 29, 2020 were collected from Chinese information system for disease control and prevention and Emergency Public Reporting System. Obtain the epidemiological survey data of the cluster epidemic situation, and clarify the scale of cluster epidemic situation, the characteristics of the index cases, family and non-family subsequent cases. Calculate serial interval according to the onset time of the index cases and subsequent cases, secondary attack rate based on the close contacts tracking results, the characteristics of different cases in the clustered epidemic were compared.Results:A total of 283 cluster were collected, including 633 index cases, 239 subsequent cases. Families are mainly clustered, the total number involved in each cluster is in the range of 2-27, M( P25, P75) are 2.0 (2.0, 4.0). During January 15 to February 29, the secondary attack rate is 2.86% (239/8 363) in Guangdong Province, the family secondary attack rate was 4.84% (276/3 697), and the non-family secondary attack rate was 1.32% (61/4 632). According to the reporting trend of the number of cases in Guangdong Province, it can be divided into four stages, the rising stage, the high platform stage, the descending stage and the low level fluctuation period. The secondary attack rate of the four stages were 3.5% (140/3 987), 2.3% (55/2 399), 2.6% (37/1 435), 1.3% (7/542), respectively. The difference was statistically significant ( P=0.003). Conclusion:COVID-19 cluster mainly occurs in families in Guangdong Province. The scale of the clustered epidemic was small; the serial interval was short; and the overall secondary attack rate was low.

Objective:Analysis of clustering characteristics of coronavirus disease 2019 (COVID-19) in Guangdong Province.Methods:The COVID-19 cases in Guangdong Province onset from January 1 to February 29, 2020 were collected from Chinese information system for disease control and prevention and Emergency Public Reporting System. Obtain the epidemiological survey data of the cluster epidemic situation, and clarify the scale of cluster epidemic situation, the characteristics of the index cases, family and non-family subsequent cases. Calculate serial interval according to the onset time of the index cases and subsequent cases, secondary attack rate based on the close contacts tracking results, the characteristics of different cases in the clustered epidemic were compared.Results:A total of 283 cluster were collected, including 633 index cases, 239 subsequent cases. Families are mainly clustered, the total number involved in each cluster is in the range of 2-27, M( P25, P75) are 2.0 (2.0, 4.0). During January 15 to February 29, the secondary attack rate is 2.86% (239/8 363) in Guangdong Province, the family secondary attack rate was 4.84% (276/3 697), and the non-family secondary attack rate was 1.32% (61/4 632). According to the reporting trend of the number of cases in Guangdong Province, it can be divided into four stages, the rising stage, the high platform stage, the descending stage and the low level fluctuation period. The secondary attack rate of the four stages were 3.5% (140/3 987), 2.3% (55/2 399), 2.6% (37/1 435), 1.3% (7/542), respectively. The difference was statistically significant ( P=0.003). Conclusion:COVID-19 cluster mainly occurs in families in Guangdong Province. The scale of the clustered epidemic was small; the serial interval was short; and the overall secondary attack rate was low.

Objective To investigate the spectrum of CYP21A2 gene mutation and the correlation between genotype and phenotype in patients with 21-hydroxylase deficiency in Tianjin and surrounding areas.Methods Genomic DNA was extracted from the peripheral blood samples of the proband.Locus-specific PCR,direct sequencing of PCR amplification products,and multiplex ligation-dependent probe amplification were applied to detect pathogenic gene CYP21A2 and the relationship between genotypes and phenotypes was analyzed.Results (1) Of 35 patients with 21-hydroxylase deficiency,25 were classified as salt-wasting phenotype and 10 were simple virilizing phenotype.(2) 69 mutant alleles were detected in a total of 70 alleles in 35 patients.Only one mutant allele was detected in one patient.Two mutant alleles were detected in all other patients,with the mutation detection rate 98.6％.(3) A total of 6 types of mutations were detected,of which c.293-13C/A＞G (I2G) was the most common,accounting for 57.1％ (40/70),followed by 18.6％ (13/70) for large gene deletion or conversion,and 14.3％ (10/70) for p.I173N.In addition,a novel mutation,c.949C＞T (p.R317X),which has not been reported previously,was detected as a pathogenic mutation.(4) Correlation analysis of genotype and phenotype in 35 children showed that the phenotype predicted by genotype was consistent with the actual salt-wasting phenotype in 31 children,and those in three children were inconsistent with the actual clinical phenotype.Conclusion The mutation characteristics of CYP21A2 gene in patients with 21-hydroxylase deficiency in Tianjin and surrounding areas are slightly different from those reported in other regions in China.A mutation c.949C＞T has not been reported,which enriches the mutation spectrum of CYP21A2 gene and provide the foundation for genetic counseling and prenatal diagnosis.

Objective: To evaluated the unplanned coverage dose to the internal mammary chain (IMC) in patient treated with postmastectomy radiotherapy (PMRT). Methods: One hundred and thirty eight patients with breast cancer receiving radiotherapy (RT) in our hospital were retrospectively analyzed. Patients were divided into three groups: three-dimensional conformal radiotherapy (3D-CRT) group, forward intensity-modulated radiotherapy (F-IMRT) group and inverse IMRT (I-IMRT) group. The IMC were contoured according to Radiation Therapy Oncology Group (RTOG) consensus, and were not include into the planning target volume (PTV). The incidental irradiation dose to IMC among the three groups and the first three intercostal spaces IMC (ICS-IMC 1-3) were all compared, and explored the relationship between the mean doses (Dmean) of IMC and the OARs (ipsilateral lung and heart). Results: The dose delivered to IMC showed no difference in CRT, F-IMRT and I-IMRT(33.80 Gy, 29.65 Gy and 32.95 Gy). And 10.42%, 2.04%, and 9.76% patients achieved ≥45 Gy when treated with CRT, F-IMRT and I-IMRT. For the IMC dose in the first three intercostal spaces (ICS1-3), there was no difference to the three treatment plannings. The Dmean, V₂₀, V₃₀, V₄₀ and V₅₀ of the ICS-IMC2 and ICS-IMC3 were all obviously superior than ICS-IMC1 for all these three plannings. Moderate positive correlation was founded between Dmean for IMC and Dmean for heart for left breast cancer patients underwent CRT (r=0.338, P=0.01). Whereas for F-IMRT and I-IMRT groups, positive correlation were founded between Dmean for IMC and Dmean and V₂₀ for ipsilateral lung for all patients (F-IMRT: r=0.366, P=0.010; r=0.318, P=0.026; I-IMRT: r=0.427, P=0.005; r=0.411, P=0.008). Conclusions In 3D-CRT, F-IMRT and I-IMRT planning methods, partial patients get IMC irradiated doses that could achieve therapeutic doses. Compared with 3D-CRT, F-IMRT and I-IMRT further reduced the dose of irradiated organs. However, there is no difference in the dose coverage of IMC for the three planned approaches when the IMC made an unplanned target.

Objective: To investigate the influencing factors of the dose coverage of unplanned internal mammary lymph node (IMN) irradiation in patients receiving chemotherapy after mastectomy. Methods: Clinical data of 138 patients receiving radiotherapy in the upper and lower lymph node drainage area of the thoracic wall and clavicle [three-dimensional conformal radiotherapy (3DCRT), field-in-field forward intensity-modulated radiotherapy (F-IMRT) or inverse IMRT (I-IMRT)] were retrospectively analyzed. The IMN was delineated according to the Radiation Therapy Oncology Group (RTOG) criteria. The unplanned irradiation dose of the IMN was obtained. The correlation between the IMN irradiation dose, clinical characteristics and specific parameters of radiotherapy during the unplanned irradiation was statistically analysed. Results: The mean dose of unplanned IMN irradiation was 32.85 Gy (range: 2.76-50.93 Gy). In total, 7.3% of breast cancer patients obtained the therapeutic dose of≥ 45 Gy. Body weight, body mass index (BMI), body surface area (BSA) and thoracic transverse diameter (D_T) were lower, whereas the planning target volume of IMN (VIMN) included in the chest wall PTV (IMNin) and the ratio of IMNin to V_IMN were higher compared with those of their counterparts with insufficient therapeutic dose. Multivariate regression analysis demonstrated that body weight, thoracic anteroposterior diameter (D_AP), D_T, R_IMNin and PTV volume were the influencing factors of the dose coverage of unplanned IMN irradiation (P=0.000, 0.000, 0.001, 0.000 and 0.034). Conclusions For patients receiving chemotherapy after mastectomy, the dose coverage significantly varies when the IMN is the unplanned target. Partial patients achieve the therapeutic dose. The dose coverage of unplanned IMN irradiation is influenced by physical characteristics, anatomical features and technical parameters of radiotherapy, which should be emphasized during the study design and result analysis.

OBJECTIVE: To explore the molecular etiology for a Chinese family affected with beta-ureidopropinoase deficiency. METHODS: Genomic DNA was extracted from the peripheral blood samples of family members. All exons and flanking intron regions of the UPB1 gene were amplified by PCR and detected by direct sequencing. The pathogenicity of identified mutation was analyzed using Polyphen2 and SIFT software. RESULTS: Compound heterozygous mutations of the UPB1 gene, including c.853G>A (p.A285T) and c.917-1G>A, were discovered in the proband, which were inherited respectively from his mother and father. Bioinformatics analysis suggested that this novel mutation was damaging. CONCLUSION The compound heterozygous mutations of the UPB1 gene probably underlie the beta-ureidopropinoase deficiency in the infant. Discovery of c.853G>A also enriched the mutation spectrum of the UPB1 gene.
Abnormalities, Multiple ; genetics ; Amidohydrolases ; deficiency ; genetics ; Asian Continental Ancestry Group ; Brain Diseases ; genetics ; China ; Exons ; Humans ; Infant ; Introns ; Movement Disorders ; genetics ; Mutation ; Pedigree ; Purine-Pyrimidine Metabolism, Inborn Errors ; genetics

OBJECTIVETo detect potential mutation in a Chinese family affected with succinic semialdehyde dehydrogenase deficiency.

METHODSGenomic DNA was extracted from the peripheral blood samples of the proband, her family members and 100 healthy controls. All exons and flanking intronic regions of the ALDH5A1 gene were amplified by PCR and subjected to direct sequencing.

RESULTSThe proband was found to have compound heterozygous mutations of the ALDH5A1 gene, namely c.398_399delAA (p.N134X) and c.638G>T (p.R213L), for which her parents were both heterozygous carriers. The same mutations were not found among the 100 healthy controls.

CONCLUSIONThe novel mutations of the ALDH5A1 gene probably underlie the pathogenesis of the disease in the infant, which also enriched the mutation spectrum of the ALDH5A1 gene.

Amino Acid Metabolism, Inborn Errors ; ethnology ; genetics ; Amino Acid Sequence ; Asian Continental Ancestry Group ; genetics ; Base Sequence ; China ; DNA Mutational Analysis ; methods ; Developmental Disabilities ; ethnology ; genetics ; Exons ; genetics ; Family Health ; Female ; Heterozygote ; Humans ; Infant ; Introns ; genetics ; Male ; Mutation ; Sequence Homology, Amino Acid ; Succinate-Semialdehyde Dehydrogenase ; deficiency ; genetics

Objective To explore pathogenic composition of hand,foot and mouth disease(HFMD),and the molecular typing of enterovirus in Tianjin Children′s Hospital in 2016.Methods Single center study.A total of 327 samples of HFMD cases which collected from Tianjin Children′s Hospital from March to November in 2016 were tested for nucleotide acid of enterovirus(EV),human enterovirus 71(EV71),Coxsackievirus A 16(CA16)by real-time reverse transcription polymerase chain reaction(RT-PCR),among which 104 sample of other EV positive were selected to amplify and sequence the whole VP1 region by using RT-PCR.Homology was analyzed and phylogenetic tree were constructed by comparison of the sequence with all subgenotype of EV by Chromas1.62 and MEGA6.06.EV positive rate in different age groups were compared by SPSS20.0.Results Of all the 327 HFMD cases tested,there were 272 EV positive cases,the constituent ratio of EV71,CA16 and other EV were 55.1％(150/272),6.6％(18/272)and 38.2％(104/272)respectively.The EV positive rates of different age groups(69.0％-90.9％)were different significantly(x2=15.897,P=0.044),the 3 years-old-group had the highest EV positive rate than that of the other age groups(90.9％,40/44).Of all 104 samples of other EV tested,34 were CA10(12.5％)and 14 were CA6(5.1％).Phylogenetic analysis of 11 EV71 VP1 and 20 CA10 VP1 showed that the EV71 and CA10 strains belonged to genotype C4a and genotype G,respectively.ConclusionsEV71 was still the predominant pathogen in spite of the constituent ratio of other EVs increased markedly in 2016 in Tianjin.It is important to enhance etiological monitoring for control and prevention of HFMD.

OBJECTIVE To detect potential mutation in a Chinese family affected with beta-ureidopropinoase deficiency. METHODS Genomic DNA was extracted from peripheral blood samples. All exons and flanking intron regions of the UPB1 gene were amplified by PCR and detected by direct sequencing. RESULTS A homozygous mutation c.977G>A was identified in exon 9 of the UPB1 gene in the proband. Both parents of the proband had heterozygous change of the same site. CONCLUSION The c.977G>A mutation of the UPB1 gene is responsible for the pathogenesis of the disease in the infant.
Abnormalities, Multiple ; genetics ; Amidohydrolases ; deficiency ; genetics ; Brain Diseases ; genetics ; Exons ; Humans ; Infant ; Male ; Movement Disorders ; genetics ; Mutation ; Purine-Pyrimidine Metabolism, Inborn Errors ; genetics

Objective To investigate the feasibility of DNA sequencing analysis in molecular diagnosis for spinal muscular atrophy (SMA). Methods Two pairs of primers were utilized to amplify the region including 5 different bases in SMA-causative gene SMN1 and its homologue copy SMN2 by polymerase chain reaction (PCR). The first primer amplified a fragment 501 bp long spanning from SMN intron 6 to intron 7 targeting four different bases (g.31957, 32006, 32154 and 32269). The second primer reversely amplified a 189 bp long fragment within SMN exon 8 including one base-pair differ-ence (g.32734). PCR procedure was followed by Sanger sequencing technique to identify the 5 different bases. SMA patients caused by SMN1 homozygous deletion were distinguished from carriers or normal controls by absence of SMN1 specific bas-es in sequence chromatograms. This assay was performed in 7 SMA suspected patients and their parents. The specimens were also detected by PCR- restriction fragment length polymorphism (RFLP) method. Results It was found that 6 of 7 SMA suspected patients showed only SMN2 specific bases at the 5 different base positions among the region from intron 6 to exon 8, which meant the patient displaying only SMN2-specific nucleotide a, T, g, g and A at g.31957, 32006, 32154, 32269 and 32734, while their parents (carriers) showed a/g, T/C, g/a, g/a and A/G at the same sites. SMN1 gene was deleted in the patient, and the deletion region was inferred from intron 6 to exon 8. Because carriers had both SMN1 and SMN2 genes, they can be discriminated from the SMN1 deleted patient. One of 7 patients yield an unique sequence chromatogram of a, T, g, g and A/G, indicating that exon 8 of SMN1 was not deleted in this patient. Conclusion DNA sequencing analysis is an alter-native simple method for detecting SMA caused by homozygous deletion of SMN1. We recommend to replace the widely used PCR-RFLP method with DNA sequencing assay.