Objective To investigate the prevalence of Schistosoma japonicum infections in wild rodents in schistosomiasis-endemic areas of China, so as to provide insights into formulation of technical guidelines for monitoring of and the precise control strategy for S. japonicum infections in wild rodents during the elimination phase. Methods Two administrative villages where schistosomiasis was historically highly prevalent were selected each from Dongzhi County, Anhui Province, and Duchang County, Jiangxi Province as study villages. Wild rodents were captured from study villages with baited traps or cages at night in June and September, 2021. The number of rodents captured was recorded, and the rodent species was characterized based on morphologi-cal characteristics. Liver tissues were sampled from captured rodents for macroscopical observation of the presence of egg granu- lomas, and S. japonicum infection was detected simultaneously using liver tissue homogenate microscopy, examinations of mesenteric tissues for parasites, and modified Kato-Katz thick smear technique (Kato-Katz technique). A positive S. japonicum infection was defined as detection of S. japonicum eggs or adult worms by any of these methods. The rate of wild rodent capture and prevalence of S. japonicum infections in wild rodents were compared in different study villages and at different time periods, and the detection of S. japonicum infections in wild rodents was compared by different assays. Results The overall rate of wild ro- dent capture was 8.28% (237/2 861) in Dongzhi County, and the wild rodent capture rates were 9.24% (133/1 439) and 7.31% (104/1 422) in two study villages (χ² = 3.503, P = 0.061), and were 8.59% (121/1 409) and 7.99% (116/1 452) in June and September, 2021, respectively (χ² = 0.337, P = 0.561). The overall rate of wild rodent capture was 3.72% (77/2 072) in Duchang County, and the wild rodent capture rates were 6.91% (67/970) and 0.91% (10/1 102) in two study villages (χ² = 51.901, P < 0.001), and were 4.13% (39/945) and 3.37% (38/1 127) in June and September, 2021, respectively (χ² = 0.815, P = 0.365). Rattus norvegicus was the predominant rodent species captured in both counties, accounting for 70.04% (166/237) of all captured wild rodents in Dongzhi County and 88.31% (68/77) in Duchang County. No S. japonicum infection was detected in wild rodents captured in Duchang County. Nevertheless, the overall prevalence of S. japonicum infections was 51.05% (121/237) in wild rodents captured in Dongzhi County, with prevalence rates of 50.38% (67/133) and 51.92% (54/104) in two study villages (χ² = 0.098, P = 0.755), and 54.31% (63/116) and 47.93% (58/121) in September and June, 2021, respectively (χ² = 0.964, P = 0.326). Of 237 wild rodents captured in Dongzhi County, there were 140 (59.07%) rodents with visible hepatic egg granulomas, 117 (49.47%) tested positive for S. japonicum eggs by liver tissue homogenate microscopy, 34 (14.35%) tested positive for S. japonicum eggs with Kato-Katz technique; however, no adult S. japonicum worms were detected in mesenteric tissues. In addition, hepatic egg granulomas were found in all wild rodents tested positive for S. japonicum eggs with liver tissue homogenate microscopy. Conclusions The rate of wild rodent capture and prevalence of S. japonicum infection in wild rodents vary greatly in schistosomiasis-endemic areas of China, and the prevalence of S. japonicum infection is slightly higher in wild rodents captured in autumn than in summer. Liver tissue is recommended as the preferred sample for surveillance of S. japonicum infection in wild rodents, and a combination of macroscopical observation of hepatic egg granulomas and liver tissue homogenate microscopy may be a standard method for surveillance of S. japonicum infection in wild rodents.

As the most common type of protein glycosylation, N-glycosylation begins with the synthesis of the dolichol-linked oligosaccharide (DLO) precursor in the endoplasmic reticulum. The mannosyltransferase Alg1 catalyzes the addition of the first mannose molecule to DLO, serving as a key enzyme in this biochemical pathway. The defect of human ALG1 gene can lead to the congenital disorders of glycosylation (CDG), i.e., ALG1-CDG. Therefore, it is of great significance to establish the expression and activity assay system of Homo sapiens Alg1 (HsAlg1) in vitro. In this study, full-length plasmid pET28a-His6-HsAlg1 and transmembrane domain-lacking plasmid pET28a-His6-HsAlg1_23-464 were constructed and expressed in Escherichia coli, and the activity of recombinant HsAlg1 and HsAlg1_23-464 was measured by liquid chromatography tandem mass spectrometry (LC-MS) with dolichyl-pyrophosphate GlcNAc2 (DPGn2) as the substrate. The results showed that HsAlg1 had transglycosylation activity, while the activity decreased after protein purification, which was partially restored upon re-addition of membrane components. However, HsAlg1_23-464 was unable to catalyze glycosylation. The results indicate that the N-terminal transmembrane domain (TMD) of HsAlg1 plays an important role in the catalytic reaction. This study lays a foundation for further expression and activity analysis of ALG1-CDG-related mutants.
Humans ; Escherichia coli/metabolism* ; Mannosyltransferases/biosynthesis* ; Glycosylation ; Recombinant Proteins/metabolism* ; Protein Domains

Objective:To summarize the clinical features and genetic effects of cases of fetal chromosomal structural abnormalities caused by maternal complex chromosomal rearrangements (CCR).Methods:Three female CCR carriers referred to the Prenatal Diagnostic Center at Guangzhou Women and Children's Medical Center, Guangzhou Medical University between October 2023 and June 2024 were retrospectively enrolled. Genetic analyses included chromosomal karyotyping, chromosomal microarray analysis (CMA), and low-coverage whole-genome copy number variation (CNV) sequencing. Clinical features of the three cases with fetal chromosomal structural abnormalities caused by maternal CCR were systematically reviewed using descriptive statistics.Results:(1) Case 1: CNV sequencing identified an 11.95 Mb duplication at 1q43q44 region of chromosome (CNV of uncertain significance) and a 36.09 Mb deletion at 5p15.33p13.2 region of chromosome (pathogenic CNV) in the fetus (maternally inherited). Maternal karyotype was 46,XX,t(1;8;3;5)(q43;q22.1;q26.2;p13.2). The pregnancy was terminated after genetic counseling. (2) Case 2: Maternal karyotype 46,XX,t(3;20)(p25;q13.1),t(6;12)(q25.2;q21.2),ins(11;14)(q23;q24q13) was transmitted to the fetus [46,XX,ins(11;14)(q23;q24q13)mat]. CMA of the fetus showed no abnormalities and the pregnancy was continued after genetic counseling. (3) Case 3: CMA of the products of conception revealed a 71.59 Mb duplication at 2p24.3p11.2 (pathogenic CNV). Maternal karyotype was 46,XX,der(2)t(2;3)(q21;q23)ins(11;2)(p13;p24p11.2),der(3)t(2;3),der(11)ins(11;2). The abnormal chromosome 2 segment in products of conception was maternally inherited.Conclusions:All three cases of fetal/abortus chromosomal abnormalities originated from maternal CCR. Early combined cytogenetic and molecular prenatal diagnosis is critical for CCR carriers during pregnancy.

Objective:To investigate genetic findings and pregnancy outcomes in fetuses with omphalocele.Methods:This retrospective study analyzed data from 502 fetuses with prenatally diagnosed omphalocele who underwent genetic testing at Guangzhou Women and Children's Medical Center and Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region between January 2014 and March 2024. Testing methods included karyotyping, chromosomal microarray analysis (CMA), methylation-specific multiplex ligation-dependent probe amplification, and whole-exome sequencing (WES). Cases were categorized as non-isolated ( n=340) or isolated ( n=162) based on ultrasound findings. Differences in genetic abnormality detection rates and pregnancy outcomes were analyzed using Mann-Whitney U test, independent samples t-test, and Chi-square test (or Fisher's exact test). Results:Among 502 fetuses, karyotyping plus CMA detected chromosomal abnormalities in 223 cases (44.4%, 223/502), including trisomy 18 (57.0%, 127/223) and trisomy 13 (23.3%, 52/223). CMA additionally identified nine pathogenic copy number variations (1.8%, 9/502) and five uniparental disomies (1.0%, 5/502), increasing the total diagnostic yield from 44.4% to 47.2%. The genetic abnormality rate was significantly lower in isolated (14.8%, 24/162) versus non-isolated omphalocele (64.7%, 220/340) ( χ2=109.34, P<0.001). WES detected variants in nine of 16 karyotype/CMA-negative cases, including five pathogenic variants involving PIK3CA and CDKN1C. Eight imprinting disorders (1.6%, 8/502) were identified, including five Beckwith-Wiedemann syndrome cases. Among 499 cases with follow-up, 401 (80.4%, 401/499) underwent pregnancy termination. Live birth rate was higher in isolated versus non-isolated groups [42.5% (69/162) vs. 8.5% (29/340), χ2=77.67, P<0.001]. Three cases were lost to follow-up. The one-year survival rate was 93.9% (92/98) in live-born infants. Conclusion:Aneuploidy (particularly trisomy 18) is the primary genetic etiology of omphalocele. CMA and WES significantly improve diagnostic yield. Isolated omphalocele has a more favorable prognosis, while non-isolated cases show significantly higher genetic abnormality rates. A stratified testing strategy is recommended: karyotyping plus CMA for isolated cases and prioritization of WES for multiple anomalies.

Objective:To summarize the clinical features and genetic effects of cases of fetal chromosomal structural abnormalities caused by maternal complex chromosomal rearrangements (CCR).Methods:Three female CCR carriers referred to the Prenatal Diagnostic Center at Guangzhou Women and Children's Medical Center, Guangzhou Medical University between October 2023 and June 2024 were retrospectively enrolled. Genetic analyses included chromosomal karyotyping, chromosomal microarray analysis (CMA), and low-coverage whole-genome copy number variation (CNV) sequencing. Clinical features of the three cases with fetal chromosomal structural abnormalities caused by maternal CCR were systematically reviewed using descriptive statistics.Results:(1) Case 1: CNV sequencing identified an 11.95 Mb duplication at 1q43q44 region of chromosome (CNV of uncertain significance) and a 36.09 Mb deletion at 5p15.33p13.2 region of chromosome (pathogenic CNV) in the fetus (maternally inherited). Maternal karyotype was 46,XX,t(1;8;3;5)(q43;q22.1;q26.2;p13.2). The pregnancy was terminated after genetic counseling. (2) Case 2: Maternal karyotype 46,XX,t(3;20)(p25;q13.1),t(6;12)(q25.2;q21.2),ins(11;14)(q23;q24q13) was transmitted to the fetus [46,XX,ins(11;14)(q23;q24q13)mat]. CMA of the fetus showed no abnormalities and the pregnancy was continued after genetic counseling. (3) Case 3: CMA of the products of conception revealed a 71.59 Mb duplication at 2p24.3p11.2 (pathogenic CNV). Maternal karyotype was 46,XX,der(2)t(2;3)(q21;q23)ins(11;2)(p13;p24p11.2),der(3)t(2;3),der(11)ins(11;2). The abnormal chromosome 2 segment in products of conception was maternally inherited.Conclusions:All three cases of fetal/abortus chromosomal abnormalities originated from maternal CCR. Early combined cytogenetic and molecular prenatal diagnosis is critical for CCR carriers during pregnancy.

Objective:To investigate genetic findings and pregnancy outcomes in fetuses with omphalocele.Methods:This retrospective study analyzed data from 502 fetuses with prenatally diagnosed omphalocele who underwent genetic testing at Guangzhou Women and Children's Medical Center and Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region between January 2014 and March 2024. Testing methods included karyotyping, chromosomal microarray analysis (CMA), methylation-specific multiplex ligation-dependent probe amplification, and whole-exome sequencing (WES). Cases were categorized as non-isolated ( n=340) or isolated ( n=162) based on ultrasound findings. Differences in genetic abnormality detection rates and pregnancy outcomes were analyzed using Mann-Whitney U test, independent samples t-test, and Chi-square test (or Fisher's exact test). Results:Among 502 fetuses, karyotyping plus CMA detected chromosomal abnormalities in 223 cases (44.4%, 223/502), including trisomy 18 (57.0%, 127/223) and trisomy 13 (23.3%, 52/223). CMA additionally identified nine pathogenic copy number variations (1.8%, 9/502) and five uniparental disomies (1.0%, 5/502), increasing the total diagnostic yield from 44.4% to 47.2%. The genetic abnormality rate was significantly lower in isolated (14.8%, 24/162) versus non-isolated omphalocele (64.7%, 220/340) ( χ2=109.34, P<0.001). WES detected variants in nine of 16 karyotype/CMA-negative cases, including five pathogenic variants involving PIK3CA and CDKN1C. Eight imprinting disorders (1.6%, 8/502) were identified, including five Beckwith-Wiedemann syndrome cases. Among 499 cases with follow-up, 401 (80.4%, 401/499) underwent pregnancy termination. Live birth rate was higher in isolated versus non-isolated groups [42.5% (69/162) vs. 8.5% (29/340), χ2=77.67, P<0.001]. Three cases were lost to follow-up. The one-year survival rate was 93.9% (92/98) in live-born infants. Conclusion:Aneuploidy (particularly trisomy 18) is the primary genetic etiology of omphalocele. CMA and WES significantly improve diagnostic yield. Isolated omphalocele has a more favorable prognosis, while non-isolated cases show significantly higher genetic abnormality rates. A stratified testing strategy is recommended: karyotyping plus CMA for isolated cases and prioritization of WES for multiple anomalies.

Objective:To investigate the correlation between clinical outcomes of congenital diaphragmatic hernia (CDH) and chromosomal abnormalities.Methods:This was a retrospective study involving 101 fetuses who underwent invasive prenatal diagnosis and chromosomal analysis for CDH at the Prenatal Diagnosis Center of Guangzhou Medical University Affiliated Women and Children's Medical Center from January 1, 2010, to December 31, 2021. According to ultrasound results, they were divided into the isolated CDH group and the complex CDH group. The results of chromosomal karyotype analysis or chromosomal microarray analysis (CMA) and birth outcomes were analyzed. For live-born children, follow-up results were analyzed. Statistical analysis was performed using t-test or Chi-square (or Fisher's exact) test. Results:(1) The mean age of the mothers of the 101 fetuses was (29.6±5.3) years, ranging from 20 to 47 years, and 16 mothers (15.8%) were over 35 years old. The mean gestational age at invasive prenatal diagnosis was (27.1±5.0) weeks, ranging from 13 weeks and 3 days to 38 weeks and 3 days; the mean gestational age at first diagnosis of CDH was (26.6±4.8) weeks, ranging from 13 weeks and 3 days to 38 weeks and 3 days. (2) The 101 fetuses were divided into isolated CDH group (81 cases, 80.2%) and complex CDH group (20 cases, 19.8%) based on whether they had other ultrasound abnormalities. Among the 20 complex cases, 13 had more than two types of malformations, with cardiovascular system malformations being the most common (11 cases, including seven chromosomal abnormalities). The highest proportion of chromosomal abnormalities was found in fetuses with central nervous system malformations (3/4). (3) Among the 101 CDH fetuses, 31 (30.7%) underwent chromosomal karyotype analysis alone, 39 (38.6%) underwent CMA alone, and 31 (30.7%) underwent both tests. The rate of chromosomal abnormalities was 13.9% (14/101). The detection rates of abnormalities by chromosomal karyotype analysis and CMA were 16.1% (10/62) and 14.3% (10/70), respectively. The additional detection rate by CMA was 2.8% (2/70). (4) The gestational age at diagnosis in the complex CDH group was earlier than that in the isolated CDH group [(22.7±4.2) weeks vs. (27.7±4.6) weeks, t=4.47, P<0.001]. The total detection rate, as well as the detection rates by chromosomal karyotype analysis and CMA, were higher in the complex CDH group than those in the isolated CDH group [45.0% (9/20) vs. 6.2% (5/81), χ2=17.13; 7/15 vs. 6.4% (3/47), χ2=10.82; 5/11 vs. 8.8% (5/57), χ2=7.55; all P<0.01]. (5) Among the 101 CDH fetuses, two were lost to follow-up, and 99 (98.0%) were successfully followed up. Among these 99 cases, 48 were terminated, and 51 were live births. The chromosomal abnormality rate in the 48 terminated fetuses was 25.0% (12/48), including 28 isolated cases and 20 complex cases. All 51 live births were isolated cases, with 45 (88.2%) cured by postnatal surgery and six (11.8%) having adverse clinical outcomes (including two preoperative deaths, three postoperative deaths, and one postoperative recurrence). Conclusions:The rate of chromosomal abnormalities in CDH is high, and it is higher in complex CDH than in isolated CDH. When prenatal diagnosis reveals fetal CDH, invasive prenatal diagnosis is recommended to exclude chromosomal karyotype abnormalities, with CMA recommended as the preferred chromosomal testing method.

Objective:To investigate the correlation between clinical outcomes of congenital diaphragmatic hernia (CDH) and chromosomal abnormalities.Methods:This was a retrospective study involving 101 fetuses who underwent invasive prenatal diagnosis and chromosomal analysis for CDH at the Prenatal Diagnosis Center of Guangzhou Medical University Affiliated Women and Children's Medical Center from January 1, 2010, to December 31, 2021. According to ultrasound results, they were divided into the isolated CDH group and the complex CDH group. The results of chromosomal karyotype analysis or chromosomal microarray analysis (CMA) and birth outcomes were analyzed. For live-born children, follow-up results were analyzed. Statistical analysis was performed using t-test or Chi-square (or Fisher's exact) test. Results:(1) The mean age of the mothers of the 101 fetuses was (29.6±5.3) years, ranging from 20 to 47 years, and 16 mothers (15.8%) were over 35 years old. The mean gestational age at invasive prenatal diagnosis was (27.1±5.0) weeks, ranging from 13 weeks and 3 days to 38 weeks and 3 days; the mean gestational age at first diagnosis of CDH was (26.6±4.8) weeks, ranging from 13 weeks and 3 days to 38 weeks and 3 days. (2) The 101 fetuses were divided into isolated CDH group (81 cases, 80.2%) and complex CDH group (20 cases, 19.8%) based on whether they had other ultrasound abnormalities. Among the 20 complex cases, 13 had more than two types of malformations, with cardiovascular system malformations being the most common (11 cases, including seven chromosomal abnormalities). The highest proportion of chromosomal abnormalities was found in fetuses with central nervous system malformations (3/4). (3) Among the 101 CDH fetuses, 31 (30.7%) underwent chromosomal karyotype analysis alone, 39 (38.6%) underwent CMA alone, and 31 (30.7%) underwent both tests. The rate of chromosomal abnormalities was 13.9% (14/101). The detection rates of abnormalities by chromosomal karyotype analysis and CMA were 16.1% (10/62) and 14.3% (10/70), respectively. The additional detection rate by CMA was 2.8% (2/70). (4) The gestational age at diagnosis in the complex CDH group was earlier than that in the isolated CDH group [(22.7±4.2) weeks vs. (27.7±4.6) weeks, t=4.47, P<0.001]. The total detection rate, as well as the detection rates by chromosomal karyotype analysis and CMA, were higher in the complex CDH group than those in the isolated CDH group [45.0% (9/20) vs. 6.2% (5/81), χ2=17.13; 7/15 vs. 6.4% (3/47), χ2=10.82; 5/11 vs. 8.8% (5/57), χ2=7.55; all P<0.01]. (5) Among the 101 CDH fetuses, two were lost to follow-up, and 99 (98.0%) were successfully followed up. Among these 99 cases, 48 were terminated, and 51 were live births. The chromosomal abnormality rate in the 48 terminated fetuses was 25.0% (12/48), including 28 isolated cases and 20 complex cases. All 51 live births were isolated cases, with 45 (88.2%) cured by postnatal surgery and six (11.8%) having adverse clinical outcomes (including two preoperative deaths, three postoperative deaths, and one postoperative recurrence). Conclusions:The rate of chromosomal abnormalities in CDH is high, and it is higher in complex CDH than in isolated CDH. When prenatal diagnosis reveals fetal CDH, invasive prenatal diagnosis is recommended to exclude chromosomal karyotype abnormalities, with CMA recommended as the preferred chromosomal testing method.

As a class of multifunctional biocatalysts, halohydrin dehalogenases are of great interest for the synthesis of chiral β-substituted alcohols and epoxides. There are less than 40 halohydrin dehalogenases with relatively clear catalytic functions, and most of them do not meet the requirements of scientific research and practical applications. Therefore, it is of great significance to excavate and identify more halohydrin dehalogenases. In the present study, a putative halohydrin dehalogenase (HHDH-Ra) from Rhodospirillaceae bacterium was expressed and its enzymatic properties were investigated. The HHDH-Ra gene was cloned into the expression host Escherichia coli BL21(DE3) and the target protein was shown to be soluble. Substrate specificity studies showed that HHDH-Ra possesses excellent specificity for 1,3-dichloro-2-propanol (1,3-DCP) and ethyl-4-chloro-3-hydroxybutyrate (CHBE). The optimum pH and temperature for HHDH-Ra with 1,3-DCP as the reaction substrate were 8.0 and 30 °C, respectively. HHDH-Ra was stable at pH 6.0-8.0 and maintained about 70% of its original activity after 100 h of treatment. The thermal stability results revealed that HHDH-Ra has a half-life of 60 h at 30 °C and 40 °C. When the temperature is increased to 50 °C, the enzyme still has a half-life of 20 h, which is much higher than that of the reported enzymes. To sum up, the novel halohydrin dehalogenase from Rhodospirillaceae bacterium possesses good temperature and pH stability as well as catalytic activity, and shows the potential to be used in the synthesis of chemical and pharmaceutical intermediates.
Escherichia coli/metabolism* ; Hydrolases/metabolism* ; Rhodospirillaceae ; Substrate Specificity

The development and application of industrial enzymes have penetrated major industrial fields. China faces a major challenge as a large country in applying enzyme but a small one in producing enzyme. Biocatalysis has become an important technology and strategy of industrial development in the world since chemical catalysis encounters the crises from resource, energy and environment. The application of efficient and clean biocatalysis is one of the important ways to realize the sustainable development of chemical industry and to modernize the fermentation industry. From perspective of the industry-university-research cooperation, we reviewed the current status and the future development of enzyme engineering from the aspects of enzyme resources, customization of enzyme molecular machine and cell factory.