Deep metagenomic characterization of the gut virome in pregnant women with preeclampsia.

Preeclampsia (PE), a pregnancy-specific syndrome, has been associated with the gut bacteriome. Here, to investigate the impact of the gut virome on the development of PE, we identified over 8,000 nonredundant viruses from the fecal metagenomes of 40 early-onset PE and 37 healthy pregnant women and profiled their abundances. Comparison and correlation analysis showed that PE-enriched viruses frequently connected to Blautia species enriched in PE. By contrast, bacteria linked to PE-depleted viruses were often the Bacteroidaceae members such as Bacteroides spp., Phocaeicola spp., Parabacteroides spp., and Alistipes shahii. In terms of viral function, PE-depleted viruses had auxiliary metabolic genes that participated in the metabolism of simple and complex polysaccharides, sulfur metabolism, lipopolysaccharide biosynthesis, and peptidoglycan biosynthesis, while PE-enriched viruses had a gene encoding cyclic pyranopterin monophosphate synthase, which seemed to be special, that participates in the biosynthesis of the molybdenum cofactor. Furthermore, the classification model based on gut viral signatures was developed to discriminate PE patients from healthy controls and showed an area under the receiver operating characteristic curve of 0.922 that was better than that of the bacterium-based model. This study opens up new avenues for further research, providing valuable insights into the PE gut virome and offering potential directions for future mechanistic and therapeutic investigations, with the ultimate goal of improving the diagnosis and management of PE.IMPORTANCEThe importance of this study lies in its exploration of the previously overlooked but potentially critical role of the gut virome in preeclampsia (PE). While the association between PE and the gut bacteriome has been recognized, this research takes a pioneering step into understanding how the gut virome, represented by over 8,000 nonredundant viruses, contributes to this condition. The findings reveal intriguing connections between PE-enriched viruses and specific gut bacteria, such as the prevalence of Blautia species in individuals with PE, contrasting with bacteria linked to PE-depleted viruses, including members of the Bacteroidaceae family. These viral interactions and associations provide a deeper understanding of the complex dynamics at play in PE.

Transcriptome analysis reveals the mechanism of pyroptosis-related genes in septic cardiomyopathy.

Background: Septic cardiomyopathy (SC) is characterized by myocardial dysfunction caused by sepsis and constitutes one of the serious complications of sepsis. Pyroptosis is a unique proinflammatory programmed cell death process. However, the role of pyroptosis in the development of SC remains unclear, and further study is required. The purpose of this study is to identify pyroptosis-related genes (PRGs) in SC and explore the mechanism of pyroptosis involved in the regulation of SC formation and progression. Methods: Differential expression analysis and enrichment analysis were performed on the SC-related dataset GSE79962 to identify differentially expressed genes (DEGs). PRGs were screened by intersecting genes associated with pyroptosis in previous studies with the DEGs obtained from GSE79962. The expression pattern of them was studied based on their raw expression data. Additionally, corresponding online databases were used to predict miRNAs, transcription factors (TFs) and therapeutic agents of PRGs. Lipopolysaccharide (LPS)-induced cell damage models in H9C2 and AC16 cell lines were constructed, cell activity was detected by CCK-8 and cell pyroptosis were detected by Hoechst33342/PI staining. Furthermore, these PRGs were verified in the external datasets (GSE53007 and GSE142615) and LPS-induced cell damage model. Finally, the effect of siRNA-mediated PRGs knockdown on the pyroptosis phenotype was examined. Results: A total of 1,206 DEGs were screened, consisting of 663 high-expressed genes and 543 low-expressed genes. Among them, ten PRGs (SOD2, GJA1, TIMP3, TAP1, TIMP1, NOD1, TP53, CPTP, CASP1 and SAT1) were identified, and they were mainly enriched in "Pyroptosis", "Ferroptosis", "Longevity regulating pathway", and "NOD-like receptor signaling pathway". A total of 147 miRNAs, 31 TFs and 13 therapeutic drugs were predicted targeting the PRGs. The expression trends of SOD2 were confirmed in both the external datasets and LPS-induced cell damage models. Knockdown of SOD2 induced increased pyroptosis in the AC16 LPS-induced cell damage model. Conclusions: In this study, we demonstrated that SOD2 is highly expressed in both the SC and LPS-induced cell damage models. Knockdown of SOD2 led to a significant increase in pyroptosis in the AC16 LPS-induced cell damage model. These findings suggest that SOD2 may serve as a potential target for the diagnosis and treatment of SC.

Immune Cell Infiltration Analysis Based on Bioinformatics Reveals Novel Biomarkers of Coronary Artery Disease.

Background: Coronary artery disease (CAD) is a multifactorial immune disease, but research into the specific immune mechanism is still needed. The present study aimed to identify novel immune-related markers of CAD. Methods: Three CAD-related datasets (GSE12288, GSE98583, GSE113079) were downloaded from the Gene Expression Integrated Database. Gene ontology annotation, Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis and weighted gene co-expression network analysis were performed on the common significantly differentially expressed genes (DEGs) of these three data sets, and the most relevant module genes for CAD obtained. The immune cell infiltration of module genes was evaluated with the CIBERSORT algorithm, and characteristic genes accompanied by their diagnostic effectiveness were screened by the machine-learning algorithm least absolute shrinkage and selection operator (LASSO) regression analysis. The expression levels of characteristic genes were evaluated in the peripheral blood mononuclear cells of CAD patients and healthy controls for verification. Results: A total of 204 upregulated and 339 downregulated DEGs were identified, which were mainly enriched in the following pathways: "Apoptosis", "Th17 cell differentiation", "Th1 and Th2 cell differentiation", "Glycerolipid metabolism", and "Fat digestion and absorption". Five characteristic genes, LMAN1L, DOK4, CHFR, CEL and CCDC28A, were identified by LASSO analysis, and the results of the immune cell infiltration analysis indicated that the proportion of immune infiltrating cells (activated CD8 T cells and CD56 DIM natural killer cells) in the CAD group was lower than that in the control group. The expressions of CHFR, CEL and CCDC28A in the peripheral blood of the healthy controls and CAD patients were significantly different. Conclusion: We identified CHFR, CEL and CCDC28A as potential biomarkers related to immune infiltration in CAD based on public data sets and clinical samples. This finding will contribute to providing a potential target for early noninvasive diagnosis and immunotherapy of CAD.

Cervical HPV infection in Guangzhou, China: an epidemiological study of 198,111 women from 2015 to 2021.

Persistent high-risk human papillomavirus (HPV) infection is the pivotal cause of cervical carcinogenesis. HPV types distribution varies greatly by region, and its long-term changes of prevalence remain to be fully characterized in China. Here, the largest population of 198,111 consecutive women who underwent routine cervical screening were investigated from 2015 to 2021 in Guangzhou, south China. The results showed that the overall HPV prevalence was 21.66% (42,911/198,111), and the annual prevalence increased significantly from 2015 to 2021 (p < 0.001). HPV52, 16, 58, CP8304, 51, 53, 39, and 68 were the most prevalent HPV types. The relative HPV-positive rate correlated positively with the progression of cervical intraepithelial neoplasia (p < 0.001); HPV16 was the predominant carcinogenic type, followed by HPV52 and HPV18. HPV infections were significantly age-specific, and 26.51% (11,375/42,911) of cases were caused by multiple HPV types. In addition, HPV infections typically cleared over a median time of 16 (interquartile range 9-31) months, and the clearance of HPV16 was significantly faster than that of other types (p < 0.001). These findings may serve as a guide for local governments to evaluate HPV vaccination and cervical cancer prevention strategies in south China.

Deep metagenomic characterization of gut microbial community and function in preeclampsia.

Preeclampsia (PE) is a pregnancy complication characterized by severe hypertension and multiple organ damage. Gut microbiota has been linked to PE by previous amplicon sequencing studies. To resolve the PE gut microbiota in a higher taxonomy resolution, we performed shotgun metagenomic sequencing on the fecal samples from 40 early-onset PE and 37 healthy pregnant women. We recovered 1,750 metagenome-assembled genomes (representing 406 species) from the metagenomic dataset and profiled their abundances. We found that PE gut microbiota had enriched in some species belonging to Blautia, Pauljensenia, Ruminococcus, and Collinsella and microbial functions such as the bacitracin/lantibiotics transport system, maltooligosaccharide transport system, multidrug efflux pump, and rhamnose transport system. Conversely, the gut microbiome of healthy pregnant women was enriched in species of Bacteroides and Phocaeicola and microbial functions including the porphyrin and chlorophyll metabolism, pyridoxal-P biosynthesis, riboflavin metabolism, and folate biosynthesis pathway. PE diagnostic potential of gut microbial biomarkers was developed using both species and function profile data. These results will help to explore the relationships between gut bacteria and PE and provide new insights into PE early warning.

[Preimplantation Genetic Diagnosis of α/ß Complex Thalassemia by Next Generation Sequencing].

OBJECTIVE: To explore the application value of next generation sequencing (NGS) in preimplantation genetic diagnosis of α/ß complex thalassemia couple. METHODS: The coding regions of α-globin genes (HBA1, HBA2) and ß-globin gene (HBB) were selected as the target regions. The high-density and closely linked single nucleotide polymorphism (SNP) sites were selected as the genetic linkage markers in the upstream and downstream 2M regions of the gene. After NGS, the effective SNP sites were selected to construct the haplotype of the couple, and the risk chromosome of the mutation carried by the couple was determined. The NGS technology was used to sequence the variations of HBA1, HBA2 and HBB directly and construct haplotype linkage analysis for preimplantation genetic diagnosis. RESULTS: Direct sequencing and haplotype linkage analysis of HBA1, HBA2 and HBB showed that two of the six blastocysts were α/ß complex thalassemia, one was ß-thalassemia heterozygote, two were α-thalassemias heterozygotes, and one was intermediate α-thalassemia. A well-developed embryo underwent preimplantation genetic diagnosis was implanted into the mother's uterus, and a healthy infant was born at term. CONCLUSION: Preimplantation genetic diagnosis can be carried out by NGS technology in α/ß complex thalassemia couples, and abortion caused by aneuploid embryo selection can be avoided.

Successful birth after preimplantation genetic testing for a couple with two different reciprocal translocations and review of the literature.

BACKGROUND: Preimplantation genetic testing for chromosomal structural rearrangements (PGT-SR) is widely applied in couples with single reciprocal translocation to increase the chance for a healthy live birth. However, limited knowledge is known on the data of PGT-SR when both parents have a reciprocal translocation. Here, we for the first time present a rare instance of PGT-SR for a non-consanguineous couple in which both parents carried an independent balanced reciprocal translocation and show how relevant genetic counseling data can be generated. METHODS: The precise translocation breakpoints were identified by whole genome low-coverage sequencing (WGLCS) and Sanger sequencing. Next-generation sequencing (NGS) combining with breakpoint-specific polymerase chain reaction (PCR) was used to define 24-chromosome and the carrier status of the euploid embryos. RESULTS: Surprisingly, 2 out of 3 day-5 blastocysts were found to be balanced for maternal reciprocal translocation while being normal for paternal translocation and thus transferable. The transferable embryo rate was significantly higher than that which would be expected theoretically. Transfer of one balanced embryo resulted in the birth of a healthy boy. CONCLUSION(S): Our data of PGT-SR together with a systematic review of the literature should help in providing couples carrying two different reciprocal translocations undergoing PGT-SR with more appropriate genetic counseling.

Early-Onset Preeclampsia Is Associated With Gut Microbial Alterations in Antepartum and Postpartum Women.

Background: Imbalances in gut microbiota composition are linked to hypertension, host metabolic abnormalities, systemic inflammation, and other conditions. In the present study, we examined the changes of gut microbiota in women with early-onset preeclampsia (PE) and in normotensive, uncomplicated pregnant women during late pregnancy and at 1 and 6 weeks postpartum. Methods: Gut microbiota profiles of women with PE and healthy pregnant women in the third trimester and at 1 and 6 weeks postpartum were assessed by 16S rRNA gene amplicon sequencing. Plasma levels of interleukin-6 (IL-6), intestinal fatty acid-binding protein (I-FABP), zonulin, and lipopolysaccharide (LPS) were measured in the third trimesters. Results: At the genus level, 8 bacterial genera were significantly enriched in the antepartum samples of PE patients compared to healthy controls, of which Blautia, Ruminococcus2, Bilophila, and Fusobacterium represented the major variances in PE microbiomes. Conversely, 5 genera, including Faecalibacterium, Gemmiger, Akkermansia, Dialister, and Methanobrevibacter, were significantly depleted in antepartum PE samples. Maternal blood pressure and liver enzyme levels were positively correlated to the PE-enriched genera such as Anaerococcus, Ruminococcus2, Oribacterium, and Bilophila, while the fetal features (e.g., Apgar score and newborn birth weight) were positively correlated with PE-depleted genera and negatively correlated with PE-enriched genera. Moreover, maternal blood IL-6 level was positively associated with gut Bilophila and Oribacterium, whereas LPS level was negatively associated with Akkermansia. In terms of postpartum women, both the gut microbial composition and the PE-associated microbial alterations were highly consistent with those of the antepartum women. Conclusion: PE diagnosed in the third trimester of pregnancy is associated with a disrupted gut microbiota composition compared with uncomplicated pregnant women, which are associated with maternal clinical features (blood pressure level and liver dysfunction) and newborn birth weight. Moreover, these antepartum alterations in gut microbiota persisted 6 weeks postpartum.

[Application of suspension array technology for the genetic diagnosis of non-syndromic hearing loss].

OBJECTIVE: To assess the value of suspension array technology (SAT) for the genetic diagnosis of non-syndromic hearing loss (NSHL). METHODS: Three hundred and sixteen NSHL patients were simultaneously tested by SAT targeting 20 hotspot mutations within 4 common pathologic genes among the Chinese population as well as 9 deafness gene mutation detection kits. The results of the two approaches were validated by Sanger sequencing. RESULTS: Among the 316 patients, 161 were found to carry a mutation by SAT. Sixty five patients have carried homozygous or compound heterozygous mutations, which yielded a mutation rate of 50.9% and a diagnostic rate of 21.2%. Seventy three patients were found to be carriers by the 9 deafness gene mutation detection kits. These included 34 patients carrying homozygous or compound heterozygous mutations, which yielded a mutation rate of 23.1% and diagnostic rate of 11.4%. Above results were consistent with those of Sanger sequencing. CONCLUSION: SAT is a simple, rapid and accurate method featuring high detection rate for common mutations related to deafness among the Chinese population and has provided an effective means of genetic testing for hereditary deafness.

A novel Y chromosome microdeletion potentially associated with defective spermatogenesis identified by custom array comparative genome hybridization.

Male infertility is a major health problem worldwide. Oligospermia and azoospermia are the most common symptoms of this disorder. Despite recent advances, the aetiopathogenesis of defective spermatogenesis remains largely uncertain. The aim of this study is to discover unknown or novel chromosome aberrations associated with male reproductive failure. We developed a high-resolution custom array comparative genomic hybridization for initial screening of copy number variations in 10 patients with idiopathic oligozoospermia and azoospermia and eight normal fertile men. We found that deletions were mainly located in the deleted-in-azoospermia subregion and were confined to patients. More importantly, an interesting microdeletion of the Y chromosome designated as D01 was detected in four out of 10 patients with oligozoospermia and azoospermia. We validated this recurrent deletion in nine out of 100 additional infertile men using polymerase chain reaction assays, whereas, it was not present in 100 proven fertile controls(P = 0.002). Furthermore, a bioinformatics analysis demonstrated that the 5' terminal of D01 is situated proximal to several conserved transcription factor binding sites within the Y chromosome. Our study indicated that this newly identified Y chromosome deletion might be potentially associated with impaired spermatogenesis and it is worthy of further investigations in larger cohorts.

[Value of Analyzing Hemoglobin A2 by ROC Curve for Screening Thalassemia].

OBJECTIVE: To investigate the value of hemoglobin A2(HbA2) for screening thalassemia. METHODS: A total of 2 000 adults' peripheral blood samples from Guangdong Women and Children Hospital from June 2013 to January 2014 were collected. The hemoglobin A2 (HbA2) level was analyzed by the full automatic capillary electrophoresis technique, and the genotypes of thalassemia were detected. RESULTS: The optimal cutoff values of HbA2 for screening silent α-thalassemia, α-thalassemia trait, intermedia α-thalassemia and ß-thalassemia trait were 2.85%, 2.65%, 2.25% and 3.45%, respectively; the areas under receiver operator characteristic (ROC) curve were 0.709, 0.839, 0.979 and 0.997 respectively; the sensitivities were 0.481, 0.721, 0.953 and 0.994, and the specificities were 0.846, 0.837, 0.929 and 0.969 respectively. CONCLUSION: The optimal cutoff values of HbA2 for screening different type of thalassemia based on our laboratory data are established by using ROC curve. According to the area under ROC curve, a satisfactory accuracy for screening intermedia α-thalassemia and ß-thalassemia trait can be achieved by detecting hemoglobin A2 level.

Molecular characterization and phylogenetic analysis of dengue virus type 1 in Guangdong in 2014.

BACKGROUND: Dengue is one of the most important emerging diseases of humans, with no preventive vaccines or antiviral cures available currently. In 2014, the Southeast Asian region experienced an unprecedented outbreak of dengue, especially in Guangdong, China. RESULTS: The nucleotide sequences of the E gene from 23 patients sera of dengue virus type 1 (DENV-1) from Guangzhou, China, were determined. One isolate that was recovered from a patient with serious liver damage was designated GZ02. The whole genome sequence of GZ02 was amplified, and confocal microscopy and plaque reduction neutralization test were performed to investigate the replication kinetics in liver L02 cells. In the study, assembly and genetic comparisons showed 11 of those E gene nucleotide sequences were absolutely accordant, and the nucleic acid sequence divergence among the other strains had no marked difference. CONCLUSIONS: Phylogenetic analysis based on the E gene indicated that the 23 new strains were closely related to strains from Malaysia or Singapore. Two different genotypes (genotype I and III) of DENV-1 were co-circulating in Guangdong, Malaysia, and Singapore from 2013 to 2014. However, no recombination event was found after 2005 between DENV strains from Guangdong and Malaysia or Singapore. GZ02 had a significant replicative advantage over DG14 and the DV1 standard strain. Importation of DENV-1 from Southeast Asian countries may have been an important contributing factor to the 2014 outbreak in Guangdong.

[Establishment of a screening method for AZF microdeletions by capillary technology and a clinical trial].

OBJECTIVE: To establish an accurate, fast and simple screening method for AZF microdeletions using capillary technology and use it for clinical testing. METHODS: For each pair of primers, the 5' end of either forward or reverse primer was labeled with a FAM, JOE or TAMRA fluorescence dyes to establish multiplex quantitative fluorescence PCR systems for the establishment of a screening method of Y chromosome AZF microdeletions by capillary technology. The detection of Y chromosome AZF microdeletion was carried out on 725 cases of non-obstructive azoospermia, oligospermia or asthenospermia. RESULTS: A screening method for Y chromosome AZF microdeletions using capillary technology was established. Thirty eight cases of AZF microdeletions were found among 725 cases of non-obstructive azoospermia, oligospermia or asthenospermia, which gave a deletion rate of 5.24%. Y chromosomal microdeletions were found in 8.62% of the azoospermia group, 6.75% of the oligozoospermic group, and 2.23% of the asthenospermia group. CONCLUSION: An accurate, fast and simple screening method of Y chromosome AZF microdeletions by capillary technology has been established, which may have an important clinical value.

Screening significantly hypermethylated genes in fetal tissues compared with maternal blood using a methylated-CpG island recovery assay-based microarray.

BACKGROUND: The noninvasive prenatal diagnosis procedures that are currently used to detect genetic diseases do not achieve desirable levels of sensitivity and specificity. Recently, fetal methylated DNA biomarkers in maternal peripheral blood have been explored for the noninvasive prenatal detection of genetic disorders. However, such efforts have covered only chromosomal aneuploidy, and fetal methylated DNA biomarkers in maternal whole blood for detecting single-gene diseases remain to be discovered. METHODS: To address this issue, we systematically screened significantly hypermethylated genes in fetal tissues and compared them with maternal peripheral blood potential in an attempt to detect fetal genes in maternal peripheral blood. First, the methylated-CpG island recovery assay combined with a CpG island array was performed for four fetus-toward placental tissues and the corresponding maternal peripheral bloods. Subsequently, direct bisulfite sequencing and combined bisulfite restriction analysis (COBRA) were carried out to validate the methylation status of the hypermethylated genes that were identified by the microarray analysis. RESULTS: Three hundred and ten significantly hypermethylated genes in the placental tissues were detected by microarray. From the top 15 hypermethylated genes detected by microarray, two were selected for sequencing validation in placental tissue and chorionic villus samples and four were selected for COBRA validation in four placental tissues, ten amniotic fluids and five chorionic villus samples. The six selected genes were confirmed to be hypermethylated in placental tissue and chorionic villus samples, but methylation of the genes could not be detected in the amniotic fluids. CONCLUSIONS: Of the many hypermethylated genes and methylation sites that were found in the fetal tissues, some have great potential to be developed into molecular markers for noninvasive prenatal diagnosis of monogenic disorders. Further clinical studies are warranted to confirm these findings.

[Prokaryotic expression of the extracellular region of human CD1d and preparation of its polyclonal antibody].

AIM: To explore the prokaryotic expression of the extracellular region of human CD1d (hCD1d) and prepare its polyclonal antibody. METHODS: The gene encoding the extracellular region of hCD1d was amplified by PCR and cloned into prokaryotic expression vector pET28, then expressed in E.coli BL21 (DE3) with IPTG induction. The recombinant protein was purified by Ni2+-NTA agarose column and then used as immunogen to immunize the mouse. The generated polyclonal antibody was evaluated by ELISA, Western blot and immunohistochemical staining (IHC), respectively. RESULTS: The recombinant extracellular region of hCD1d was successfully expressed and purified. The polyclonal antibody with high titer and high specificity was obtained, which could recognize the native hCD1d in the human small intestinal tissues. CONCLUSION: The recombinant extracellular region of hCD1d has been obtained. The antibody with high titer and high specificity against the extracellular region of hCD1d from the mouse has been successfully prepared, which lays a foundation for further research into the detection and functional study of CD1d.

[Preparation and characterization of the rabbit polyclonal antibody against the alpha3 domain of human CD1d].

AIM: To prepare the rabbit antibody against the alpha3 domain of the human CD1d (hCD1d-alpha3). METHODS: The gene fragment coding for hCD1d-alpha3 was amplified by PCR and cloned into prokaryotic expression vector pET28, then expressed in E.coli BL21(DE3). The recombinant protein hCD1d-alpha3 was purified with Ni(2+)-NTA agarose column and used as immunogen to immunize the rabbit. The titer and specificity of the anti-hCD1d-alpha3 antibody from the rabbit were analyzed by ELISA, Western blot and immunohistochemistry, respectively. RESULTS: The recombinant hCD1d-alpha3 was successfully expressed and purified, and the polyclonal anit-hCD1d-alpha3 antibody was successfully prepared. The titer of the antiserum was 1:6 400 by ELISA. Western blot analysis showed this antiboday reacted specifically with hCD1d. Immunohistochemistry analysis showed the antibody could recognize the native hCD1d in the human intestinal tissue. CONCLUSION: The anti-CD1d-alpha3 antibody from the rabbit with high titer and specificity has been prepared with purified recombinant hCD1d-alpha3 as immunogen, which lays a foundation for further research into detection and functional study of CD1d.

[Prokaryotic expression of human mast cell chymase gene and preparation of its polyclonal antibody].

AIM: To express the human mast cell chymase cDNA in E.coli and prepare the antibody against human mast cell chymase with recombinant chymase. METHODS: The human mast cell chymase cDNA was cloned by RT-PCR. The recombinant chymase was expressed in E.coli with L-Arabinose induction and purified by Ni-NTA agarose column. Then the purified chymase was used as immunogen to immunize the rabbit. The titer and specificity of the anti-chymase antibody from the rabbit were analyzed by indirect ELISA and Western blot, respectively. RESULTS: The recombinant chymase was successfully expressed in E.coli, and the polyclonal anit-chymase antibody was prepared by immunizing the rabbit with the purified recombinant chymase. The titer of the generated antiserum was detected to be 1:12 800 by ELISA. Western blot analysis showed this antibody bound specifically with chymase. CONCLUSION: The anti-chymase antibody from the rabbit with high titer and specificity has been prepared with purified recombinant chymase as immunogen, which lays a foundation for further research into detection and function of chymase.

[Evaluation on effects of chromogenic medium in rapid detection of Coliform and Escherichia coli].

OBJECTIVE: To evaluate the detective efficacy of Chromogenic Coliform and Escherichia Coli Agar (CCEA). METHODS: A new chromogenic medium CCEA prepared by Huankai laboratory was used to compare with a classical medium of violet red bile agar (VRBA), and other two Chromogenic media Agar I and Agar II by detecting separately 11 reference strains, thirteen sterile samples with Coliform or E.coli and other four samples, and the accordant rates of detection were observed. RESULTS: CCEA had the good selectivity. To seven kinds of quality strains in the resultant analysis, CCEA with VRBA and Agar I had not shown salience difference (P > 0.05), and CCEA with Agar II had significant difference (P < 0.05). CCEA showed more advantages than the Agar II. To thirteen sterile samples with Coliform or E.coli in resultant analysis, CCEA with Agar I and Agar II had shown no significant difference (P > 0.05), while CCEA with VRBA had significant difference (P < 0.05). CCEA might be more advantageous than the VRBA. In analysis of the four actual samples of Coliform, CCEA with VRBA, Agar I and Agar II showed no significant difference (P > 0.05). The accordant rates were 90%, 71.88%, 86.25% and 81.25% respectively, showing CCEA > Agar I > Agar II > VRBA. To two actual samples of E.coli in the resultant analysis, the CCEA with Agar I and Agar II had not shown significant difference (P > 0.05). The accordant rates were 100% respectively. CONCLUSIONS: The CCEA might be more advantageous than the VRBA, having the same efficacy as with Agar I and Agar II.

[Preparation and characterization of rabbit antibody against human mast cell carboxypeptidase].

AIM: To prepare antibody against human mast cell carboxypeptidase (hMC-CP) by using recombinant hMC-CP expressed in E.coli, and to characterize the antibody. METHODS: hMC-CP was expressed in E.coli with L-Arabinose induction and purified through Ni-NTA column. The purified hMC-CP as immunogen was used to immunize rabbit. The titer and the specificity of the rabbit anti-hMC-CP antibody was analyzed by indirect ELISA and Western blot respectively. RESULTS: The hMC-CP was successfully expressed and purified. The polyconal anit-hMC-CP antibody was prepared by immunizing rabbit using the purified recombinant protein, The titer of the generated antiserum was 1:6 400 by ELISA. Western blot analysis showed that this antibody could bind with hMC-CP specifically. CONCLUSION: The rabbit anti-hMC-CP antibody with high titer and high specificity has been prepared by using purified recombinant hMC-CP as immunogen, which lays the foundation for further research on detection and function of hMC-CP.