A Comparative Study of Associated Microbiota Between Pig Farm and Pig Slaughterhouse in Guangdong, China.

The goal of this study was to compare the microbiota in different pig-present settings in China. Bioaerosol samples from pig farms and slaughterhouses and nasal samples from pig farmers and slaughterhouse workers were collected in Guangdong, southern China. The bacterial genomic DNA was isolated and subjected to 16S sequencing. The data were analyzed using QIIME2 with the DADA2 pipeline. A total of 14,923,551 clean reads and 2785 operational taxonomic units (OTUs) were obtained, which were mostly grouped into 4 phyla (Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria) and 220 families. The microbiota richness of nasal samples in pig-present workers was higher than that of bioaerosols collected in the vicinity of the pig enclosures. There were 31.7% (620/1954) shared OTUs between pig farm bioaerosols and pig farmers which was higher than that between pig slaughterhouses and slaughterhouse workers (23.4%, 364/1553) (p < 0.001). Acinetobacter and Pseudomonas were the most abundant in pig-present bioaerosols, and Staphylococcus, Pseudomonas, and Corynebacterium were dominant bacterial genus in pig farmers. The bacterial patterns are also specific to the location of sample collected. The results suggest that bioaerosol microbiota interact with human nasal microbes in the vicinity of the pig farm enclosures, providing the basis for further analysis of microbial transmission across hosts in pig-present settings.

A preliminary analysis of microRNA as potential clinical biomarker for schizophrenia.

MicroRNAs (miRNA, miR) have been implicated as promising blood-based biomarkers for schizophrenia patients. This study aimed to clinically validate miRNA as potential schizophrenia biomarkers. Plasma levels of 10 miRNAs were analyzed using qPCR in a cohort of 61 schizophrenia patients and 62 normal controls, as well as 25 patients particularly selected for a six-week antipsychotic treatment course. Positive And Negative Syndrome Scale (PANSS), Global Assessment Scale (GAS) and Clinical Global Impression (CGI) were administered to assess the clinical symptoms. The results demonstrated that a panel of miRNAs consisting of miR-30e, miR-181b, miR-34a, miR-346 and miR-7 had significantly increased expression levels with significant combined diagnostic value (AUC:0.713; sensitivity:35.5%; specificity:90.2%). In response to pharmacological treatment, expression levels of miR-132, miR-181b, miR-432 and miR-30e were significantly decreased. In addition, the improvement of clinical symptomatology was significantly correlated with the changes of miR-132, miR-181b, miR-212 and miR-30e expression levels. Furthermore, the decreases of plasma levels of miR-132 and miR-432 were significantly greater in high-effect subgroup than those in low-effect subgroup after six-week treatment course. We conclude that miR-30e, miR-181b, miR-34a, miR-346 and miR-7 combined as a panel are potentially useful non-invasive biomarkers for schizophrenia diagnosis. Markers miR-132, miR-181b, miR-30e and miR-432 are potential indicators for symptomatology improvements, treatment responses and prognosis for schizophrenia patients.

A meta-transcriptomic study of mosquito virome and blood feeding patterns at the human-animal-environment interface in Guangdong Province, China.

Mosquitoes are a formidable reservoir of viruses and important vectors of zoonotic pathogens. Blood-fed mosquitoes have been utilized to determine host infection status, overcoming the difficulties associated with sampling from human and animal populations. Comprehensive surveillance of potential pathogens at the interface of humans, animals, and the environment is currently an accredited method to provide an early warning of emerging or re-emerging infectious diseases and to proactively respond to them. Herein we performed comprehensive sampling of mosquitoes from seven habitats (residential areas, hospital, airplane, harbor, zoo, domestic sheds, and forest park) across five cities in Guangdong Province, China. Our aim was to characterize the viral communities and blood feeding patterns at the human-animal-environment interface and analyze the potential risk of cross-species transmission using meta-transcriptomic sequencing. 1898 female adult mosquitoes were collected, including 1062 Aedes and 836 Culex mosquitoes, of which approximately 12% (n = 226) were satiated with blood. Consequently, 101 putative viruses were identified, which included DNA and RNA viruses, and positive-stranded RNA viruses (+ssRNA) were the most abundant. According to viral diversity analysis, the composition of the viral structure was highly dependent on host species, and Culex mosquitoes showed richer viral diversity than Aedes mosquitoes. Although the virome of mosquitoes from different sampling habitats showed an overlap of 39.6%, multiple viruses were specific to certain habitats, particularly at the human-animal interface. Blood meal analysis found four mammals and one bird bloodmeal source, including humans, dogs, cats, poultry, and rats. Further, the blood feeding patterns of mosquitoes were found to be habitat dependent, and mosquitoes at the human-animal interface and from forests had a wider choice of hosts, including humans, domesticated animals, and wildlife, which in turn considerably increases the risk of spillover of potential zoonotic pathogens. To summarize, we are the first to investigate the virome of mosquitoes from multiple interfaces based on the One Health concept. The characteristics of viral community and blood feeding patterns of mosquitoes at the human-animal-environment interface were determined. Our findings should support surveillance activities to identify known and potential pathogens that are pathogenic to vertebrates.

An occupational risk of hepatitis E virus infection in the workers along the meat supply chains in Guangzhou, China.

Hepatitis E virus (HEV) causes infections in humans and animals. HEV have been identified in pig farms, markets and swine workers, but studies with parallel observations along the poultry and pork supply chains remains limited. This study aimed to characterize HEV infection risks in workers along the meat supply chain. Two rounds of cross-sectional surveys were performed among swine and poultry workers in pig and poultry farms, slaughterhouses, wholesale and retail live poultry markets, live pig markets and pork markets. Human sera from the workers and the general population were collected and tested for HEV specific IgM/IgG antibodies by commercial indirect-ELISA test kits. Risk factors of HEV seropositivity associated with different occupational settings were identified using logistic regression. 47.0% (156/332) of the swine workers and 40.2% (119/296) of the poultry workers were seropositive, compared to 26.1% (35/134) in the general population. Multivariable analysis showed that human HEV infection risk increased along the pork supply chain, with the highest risk at pig slaughterhouses (adjusted OR = 3.19, 95% CI = 1.49-6.88) and pork markets (adjusted OR = 2.02, 95% CI = 1.04-3.97), but no significant higher risk was observed among poultry workers. Swine occupational exposure is associated with HEV infection, especially in workers in pig slaughterhouses and pork markets. Strengthening control measures in these settings is important for HEV control and long term HEV elimination.

Genomic characterization of Wenzhou mammarenavirus detected in wild rodents in Guangzhou City, China.

Wenzhou mammarenavirus (WENV) is a zoonotic pathogen newly discovered in east and southeast Asia. WENV has been found in wild rodent animals around the world while its standing is barely understood in Guangzhou city, where is known as a region of outbreak hotspot for zoonotic emerging infectious diseases. To investigate the prevalence and genomic characteristics of mammarenavirus in Guangzhou City, lung tissue samples from wild rodent species were collected from five districts of Guangzhou City in the year 2015 and 2016. The viral RNA was extracted and then subjected to mammarenavirus-specific PCR. The result revealed approximately 1.0% (3/306) nucleic acid positivity for lung tissue samples obtained from three rodent species: Mus musculus, Rattus flavipectus, and Rattus norvegicus. Viral metagenomic sequencing of three samples was then carried out and two full segment L and three full segment S sequences were obtained. Phylogenetics analysis indicated the sequences of the new mammarenavirus strain have 76.2% - 94.4% similarity to known WENV encoded genes, with the highest similarity to the WENV 9-24 strain. Population structure analysis grouped all known WENV into seven lineages, and this WENV Guangzhou strain was grouped with WENV 9-24 as well. Though the seroprevalence result was not available, our data provides the first nucleic acid evidence of circulating WENV in Guangzhou city, and it suggested WENV had a broader host tropism than previously known.

Distribution of the COVID-19 epidemic and correlation with population emigration from Wuhan, China.

BACKGROUND: The ongoing new coronavirus pneumonia (Corona Virus Disease 2019, COVID-19) outbreak is spreading in China, but it has not yet reached its peak. Five million people emigrated from Wuhan before lockdown, potentially representing a source of virus infection. Determining case distribution and its correlation with population emigration from Wuhan in the early stage of the epidemic is of great importance for early warning and for the prevention of future outbreaks. METHODS: The official case report on the COVID-19 epidemic was collected as of January 30, 2020. Time and location information on COVID-19 cases was extracted and analyzed using ArcGIS and WinBUGS software. Data on population migration from Wuhan city and Hubei province were extracted from Baidu Qianxi, and their correlation with the number of cases was analyzed. RESULTS: The COVID-19 confirmed and death cases in Hubei province accounted for 59.91% (5806/9692) and 95.77% (204/213) of the total cases in China, respectively. Hot spot provinces included Sichuan and Yunnan, which are adjacent to Hubei. The time risk of Hubei province on the following day was 1.960 times that on the previous day. The number of cases in some cities was relatively low, but the time risk appeared to be continuously rising. The correlation coefficient between the provincial number of cases and emigration from Wuhan was up to 0.943. The lockdown of 17 cities in Hubei province and the implementation of nationwide control measures efficiently prevented an exponential growth in the number of cases. CONCLUSIONS: The population that emigrated from Wuhan was the main infection source in other cities and provinces. Some cities with a low number of cases showed a rapid increase in case load. Owing to the upcoming Spring Festival return wave, understanding the risk trends in different regions is crucial to ensure preparedness at both the individual and organization levels and to prevent new outbreaks.

Rabies trend in China (1990-2007) and post-exposure prophylaxis in the Guangdong province.

BACKGROUND: Rabies is a major public-health problem in developing countries such as China. Although the recent re-emergence of human rabies in China was noted in several epidemiological studies, little attention was paid to the reasons behind this phenomenon paralleling the findings of the previous reports. The purpose of this study is thus first to characterize the current trends of human rabies in China from 1990 to 2007, and then to define better recommendations for improving the post-exposure prophylaxis (PEP) schedules delivered to rabies patients. METHODS: The most updated epidemiological data for 22527 human rabies cases from January 1990 to July 2007, retrieved from the surveillance database of reportable diseases managed by the Ministry of Health of China, were analysed. To investigate the efficiency for the post-exposure treatment of rabies, the details of 244 rabies patients, including their anti-rabies treatment of injuries or related incidents, were ascertained in Guangdong provincial jurisdiction. The risk factors to which the patients were predisposed or the regimens given to 80 patients who received any type of PEP were analysed to identify the reasons for the PEP failures. RESULTS: The results from analysis of the large number of human rabies cases showed that rabies in China was largely under control during the period 1990-1996. However, there has been a large jump in the number of reported rabies cases since 2001 up to a new peak (with an incidence rate of 0.20 per 100000 people) that was reached in 2004, and where the level has remained until present. Then, we analysed the PEP in 244 rabies cases collected in the Guangdong province in 2003 and 2004, and found that 67.2% of the patients did not seek medical services or did not receive any PEP. Further analysis of PEP for the 80 rabies patients who received any type of PEP indicated that almost all of the patients did not receive proper or timely treatment on the wounds or post-exposure vaccination or rabies immunoglobulins. CONCLUSION: While the issue of under-reporting of rabies in previous years may well be a factor in the apparent upwards trend of human rabies in recent years, the analysis of PEP in the Guangdong province provides evidence that suggests that the failure to receive PEP was a major factor in the number of human cases in China. Thus, the data underline the need for greatly improved availability and timely application of high-quality anti-rabies biologicals, both vaccines and immunoglobulins, in the treatment of human bite victims. Controlling dog rabies through pet vaccination schemes may also play a huge role in reducing the rate of human exposure. Education of the public, health care staff and veterinarians will also help to change the current situation.

Alterations of GPI transamidase subunits in head and neck squamous carcinoma.

BACKGROUND: GPI anchor attachment is catalyzed by the GPI transamidase (GPIT) complex. GAA1, PIG-T and PIG-U are the three of five GPIT subunits. Previous studies demonstrated amplification and overexpression of GPIT subunits in bladder and breast cancer with oncogenic function. We performed an analysis of these subunits in head and neck squamous cell carcinoma (HNSCC). RESULTS: To evaluate GAA1, PIG-T and PIG-U in HNSCC, we used quantitative PCR (QPCR) and quantitative RT-PCR (QRT-PCR) to determine the copy number of those genes in primary tumors and the matching lymphocytes in 28 patients with HNSCC and quantified RNA expression of those genes in 16 primary HNSCC patients and 4 normal control tissue samples. GAA1 showed a significant increase in normalized mRNA expression, 2.11 (95% CI: 1.43, 2.79), in comparison to that of normal controls, 0.43 (95% CI: -0.76, 1.61), p = 0.014 (Mann-Whitney test). The mean genomic copy number of GAA1 was significantly increased in HNSCC, 0.59 (95% CI: 0.50, 0.79), in comparison to lymphocyte DNA, 0.35 (95% CI: 0.30, 0.50), p = 0.001 (paired t-test). CONCLUSION: An increased expression level and elevated copy number for GAA1 suggest a role for this GPI anchor subunit in HNSCC.

Rescue of the albino phenotype by introducing a functional tyrosinase minigene into Kunming albino mice.

AIM: To use the tyrosinase minigene as a visual marker to perform microinjection training and improve the techniques related with transgene to greatly elevate the efficiency of gene transfer. METHODS: A mouse tyrosinase minigene, i.e., TyBS, in which the 2.25-kb authentic genomic 5' non-coding flanking sequence of mouse tyrosinase was fused to a mouse tyrosinase cDNA, was introduced into the fertilized eggs of outbred Kunming albino mice. RESULTS: Of the 11 animals that developed from the injected eggs, two mice (P1 and #8) exhibited pigmented hair (P1) and eyes (P1 and #8), as confirmed by PCR analysis for the tyrosinase minigene integrated into the genome. When founder P1 was bred to Kunming male mouse, six progeny out of 11 offspring inherited the transgene and the pigmented-eye phenotype. CONCLUSION: Taken together, these results suggest that this minigene encodes the active tyrosinase protein and that its 5' flanking region contains the sequences regulating the expression of mouse tyrosinase gene as expected. We have rescued the albino phenotype by introduction and expression of a functional tyrosinase minigene in the Kunming albino mouse and the transgene can be passed to subsequent generation. These findings also indicate that TyBS can be a useful visual marker gene in the co-transgenic experiments.

Comparison of effectiveness of whole viral, N and N199 proteins by ELISA for the rapid diagnosis of severe acute respiratory syndrome coronavirus.

BACKGROUND: Although severe acute respiratory syndrome (SARS) has been controlled, the subsequently emerging sporadic cases in 2004 emphasize the necessity of developing a rapid diagnostic method, which would be of great help in clinical diagnosis and also wild host screening. This study aims to establish an effective and rapid serological tool for the diagnosis of SARS-CoV by comparison among whole viral, N and N199 proteins by ELISA. METHODS: SARS-CoV N and N199 (a truncated nucleocapsid gene) genes were cloned, expressed, identified by Western blotting, and applied in screening of human and swine samples. Sera of SARS convalescent-phase patients, normal human sera, sera of patients with other respiratory diseases, and swine sera were screened by ELISA, with whole SARS-CoV F69, N and N199 proteins as antigens. RESULTS: The sensitivity and specificity of N and N199 proteins in human sera diagnosis were approximate (P = 0.743), which was higher than whole viral protein but the difference was not significant (P = 0.234). The N199 protein proved to be more specific in swine sera screening than whole viral and N protein (P < 0.001). CONCLUSION: N199 protein is feasible in both clinical diagnosis and SARS-CoV reservoir screening.

[Making of the animal model with sterilized testes].

OBJECTIVE: To explore the methods of making an animal model with sterilized testes. METHODS: (1) X-ray local irradiation. Seventy 8-10-week-old male mice were equally divided into 6 experiment groups and a control group. The testes of the mice in the 6 experiment groups were irradiated sequentially by 1000, 1200, 1400, 1600, 1800 and 2000 cGy X-ray for 10 minutes, while those in the control group remained untreated. And then the pregnancy test was performed. (2) Cyclophosphamide injection. Forty 4-5-week-old male mice were divided into 3 experiment groups and a control group, the former treated with different doses of Cyclophosphamide via ip and the latter Natiichloridi Saline (N.S.) via i.p., followed by the pregnancy test. (3) Diphereline injection. Twenty 8-10-week-old male mice were equally divided into an experiment group and a control group, the former treated with Diphereline via ip and the latter N.S. via i.p., followed by the pregnancy test. (4) Identification by such pathologic examinations as TUNE1. technology, HE staining and immunohistochemical staining. RESULTS: (1) X-ray local irradiation. The male mice of Group 1 and 2 made their female partners pregnant respectively 10 and 15 days after the X-ray irradiation, but not those of Group 3 and 4 in our 3-month observation, and those of Group 5 and 6 died respectively 2 and 5 days after the X-ray irradiation. By comparison, the controls got their female partners pregnant within 3 days after placed together. (2) Cyclophosphamide injection. The male mice of Group 1 gained weight about 7 g and achieved pregnancy 9-14 days after drug termination, those of Group 2 gained around 4 g but failed to effect pregnancy, and those in Group 3 lost weight and died respective at 3, 4 and 5 weeks during the medication, while the controls all got their female partners pregnant within 3 days after put together. (3) Diphereline injection. The 10 male mice of the experiment group effected pregnancy 3 weeks after drug termination, while the 10 controls achieved the same result with 3 days after placed together. (4) Pathologic identification: TUNEL technology showed that apoptotic cells were occasionally seen (0.71 +/- 0.12)% in the testis tissue of the control group and remarkably increased (10.36 +/- 1.48)% in the model group, with significant difference between the two groups (P < 0.05). HE staining revealed normal testis tissues and convoluted seminiferous tubules with large numbers of germ cells in the control group, but atrophied convoluted seminiferous tubules and estranged cell linkage with only Ledig's cells but no germ cells in the model group. Immunohistochemical staining showed that the positive expression rates of CD29, Hsp90alpha and CD117 were respectively (50.30 +/- 5.2)%, (41.6 +/- 3.5)% and (73.6 +/- 3.7)% in the control group, as compared with (1.3 +/- 0.2)%, 0% and (1.6 +/- 0.3)% in the model group, with significant difference (P < 0.01). The positive expression rate of p53 was (19.7 +/- 0.8)% in the control group, significantly different from that of the model group, which was (39.4 +/- 2.9)% (P < 0.01). CONCLUSION: The animal model with sterilized testes can be made either by X-ray local irradiation of the testis or by Cyclophosphamide injection via i.p..

[Mesenchymal stem cells do not differentiate into "quasi-sperm"].

OBJECTIVE: To determine whether the surviving mesenchymal stem cells (MSCs) in the testis after transplantation can differentiate into quasi-sperm. METHODS: (1) Making an animal model with sterilized testes. Forty 4-week old white male BASB/C mice were used to establish an animal model with sterilized testes and divided randomly into an experimental and a control group. (2) Cell preparation. The MSCs from 10 gray male 129-mice were isolated, cultured and purified by Percoll density gradient centrifugation combined with the adherent method. When the MSCs grew to an adequate number, they were made into a cell suspension with NS at a concentration of 1 million cells/ml. (3) Xenogeneic transplantation of the MSCs into the testis. The MSC suspension was blindly injected into the testes of the mice in the experimental group and NS into the testes of the controls. (4) Post-transplantation observation. Forty white female BASB/C mice were adopted, each put into a box with a male mouse from the experimental group or the control group, and then observed for pregnancy. RESULTS: In the experimental group, 8 cases of pregnancy (40%) were observed at 31-46 d (38.5 d on average), the offspring all white. In the control group, only 1 case of pregnancy (5%) was seen at 45 d, the offspring all white, too. It was suggested that the MSCs of the 129-mice failed to differentiate into functional quasi-sperm and pass their genes to their offspring, as would expectedly have been presented by a mixture of black and white. The pregnancy rates of the two groups were significantly different (P < 0.05), which indicated that MSCs could promote the healing of the testis damage. CONCLUSION: MSCs cannot differentiate into quasi-sperm after heterogeneity transplantation into the testis, but can promote the healing of the testis damage.

Generation of the regulatory protein rtTA transgenic mice.

AIM: To translate Tet-on system into a conditional mouse model, in which hepatitis B or C virus (HBV or HCV) gene could be spatiotemporally expressed to overcome "immune tolerance" formed during the embryonic development and "immune escape" against hepatitis virus antigen(s), an effector mouse, carrying the reverse tetracycline-responsive transcriptional activator (rtTA) gene under the tight control of liver-specific human apoE promoter, is required to be generated. METHODS: To address this end, rtTA fragment amplified by PCR was effectively inserted into the vector of pLiv.7 containing apoE promoter to create the rtTA expressing vector, i.e., pApoE-rtTA. ApoE-rtTA transgenic fragment (-6.9 kb) released from pApoE-rtTA was transferred into mice by pronucleus injection, followed by obtaining one transgene (+) founder animal from microinjection through PCR and Southern blot analysis. RESULTS: rtTA transgene which could be transmitted to subsequent generation (F1) derived from founder was expressed in a liver-specific fashion. CONCLUSION: Taken together, these findings demonstrate that rtTA transgenic mice, in which rtTA expression is appropriately targeted to the murine liver, are successfully produced, which lays a solid foundation to 'off-on-off' regulate expression of target gene (s) (e.g., HBV and/or HCV) in transgenic mice mediated by Tet-on system.

Variation analysis of the severe acute respiratory syndrome coronavirus putative non-structural protein 2 gene and construction of three-dimensional model.

BACKGROUND: The rapid transmission and high mortality rate made severe acute respiratory syndrome (SARS) a global threat for which no efficacious therapy is available now. Without sufficient knowledge about the SARS coronavirus (SARS-CoV), it is impossible to define the candidate for the anti-SARS targets. The putative non-structural protein 2 (nsp2) (3CL(pro), following the nomenclature by Gao et al, also known as nsp5 in Snidjer et al) of SARS-CoV plays an important role in viral transcription and replication, and is an attractive target for anti-SARS drug development, so we carried on this study to have an insight into putative polymerase nsp2 of SARS-CoV Guangdong (GD) strain. METHODS: The SARS-CoV strain was isolated from a SARS patient in Guangdong, China, and cultured in Vero E6 cells. The nsp2 gene was amplified by reverse transcription-polymerase chain reaction (RT-PCR) and cloned into eukaryotic expression vector pCI-neo (pCI-neo/nsp2). Then the recombinant eukaryotic expression vector pCI-neo/nsp2 was transfected into COS-7 cells using lipofectin reagent to express the nsp2 protein. The expressive protein of SARS-CoV nsp2 was analyzed by 7% sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). The nucleotide sequence and protein sequence of GD nsp2 were compared with that of other SARS-CoV strains by nucleotide-nucleotide basic local alignment search tool (BLASTN) and protein-protein basic local alignment search tool (BLASTP) to investigate its variance trend during the transmission. The secondary structure of GD strain and that of other strains were predicted by Garnier-Osguthorpe-Robson (GOR) Secondary Structure Prediction. Three-dimensional-PSSM Protein Fold Recognition (Threading) Server was employed to construct the three-dimensional model of the nsp2 protein. RESULTS: The putative polymerase nsp2 gene of GD strain was amplified by RT-PCR. The eukaryotic expression vector (pCI-neo/nsp2) was constructed and expressed the protein in COS-7 cells successfully. The result of sequencing and sequence comparison with other SARS-CoV strains showed that nsp2 gene was relatively conservative during the transmission and total five base sites mutated in about 100 strains investigated, three of which in the early and middle phases caused synonymous mutation, and another two base sites variation in the late phase resulted in the amino acid substitutions and secondary structure changes. The three-dimensional structure of the nsp2 protein was successfully constructed. CONCLUSIONS: The results suggest that polymerase nsp2 is relatively stable during the phase of epidemic. The amino acid and secondary structure change may be important for viral infection. The fact that majority of single nucleotide variations (SNVs) are predicted to cause synonymous, as well as the result of low mutation rate of nsp2 gene in the epidemic variations, indicates that the nsp2 is conservative and could be a target for anti-SARS drugs. The three-dimensional structure result indicates that the nsp2 protein of GD strain is high homologous with 3CL(pro) of SARS-CoV urbani strain, 3CL(pro) of transmissible gastroenteritis virus and 3CL(pro) of human coronavirus 229E strain, which further suggests that nsp2 protein of GD strain possesses the activity of 3CL(pro).

[Isolation and culture of mouse marrow mesenchymal stem cells (MSCs) and biological characteristics of MSCs cultured in conditions for spermatogonia in vitro].

OBJECTIVE: To isolate, culture and purify mouse bone marrow mesenchymal stem cells (MSCs) and observe the main biological characteristics of MSCs cultured in conditions for spermatogonia in vitro. METHODS: The tibias and femurs were dissected from 5 - 6-week old mice and the marrow in the tibias and femurs was flushed out with medium. MSCs were isolated, cultured, purified in vitro by Percoll density gradient centrifugation combined with adherent method and identified by dynamic observation of stem cell characteristics by transmission electron microscope, HE staining, and immunohistochemical detection of cell markers. The quantities of such cytokines as IL-6, IL-8, G-CSF and SCF in culture liquid with MSCs were measured by ELISA, and compared with those of the control group. MSCs of the third generation were divided into two groups to be induced and cultured. MSCs of the control group were cultured with basal medium, while those of the experimental group with conditional medium. The results were analysed by microscopic observation, HE staining and immunohistochemical methods. RESULTS: Pure MSCs were obtained. The cultured cells, with stem cell characteristics, shuttle-shaped at HE staining, immature under the transmission electron microscope and CD44 and CD90 positive by immunohistochemical detection, could be identified as MSCs. Compared with the control group, the quantities of IL-6, IL-8, G-CSF and SCF in the experimental group increased significantly (P < 0.05). The shapes of MSCs changed and immunohistochemical staining for CD27, CD119 and Oct-4 was positive in the experimental group, but both were just the opposite in the control group. CONCLUSION: Pure MSCs can be obtained by Percoll density gradient centrifugation combined with adherent method and identified by dynamically observing stem cell characteristics, HE staining, observation under the transmission electron microscope and immunohistochemical detection of cell markers. MSCs can secrete cytokines such as IL-6, IL-8, G-CSF, SCF, and so on. MSCs cultured in conditions for spermatogonia may show some biological characteristics of spermatogonia.

[Transplantation of mouse bone marrow mesenchymal stem cells into the xenogeneic testis].

OBJECTIVE: To study transplantation of mouse bone marrow mesenchymal stem cells (MSCs) into the xenogeneic testis. METHODS: (1) The tibias and femurs were dissected from 5-6-week-old mice. The marrow in the tibias and femurs was flushed out with medium. MSCs were isolated, cultured and purified in vitro by Percoll density gradient centrifugation combined with adherent method. (2) MSCs of the third generation were adopted and marked with Hoechest33342 for observation, and then made into cell-suspending fluid. (3) The marked MSCs were transplanted into the testis of the xenogeneic mouse by testis net injection. The biopsies of the testis tissues were carried out at different time and made into frost slices at three sites for observation. RESULTS: (1) A lot of purified MSCs were obtained at the third generation. (2) The nucleoli of the marked MSCs showed light-yellow under the fluoroscope. (3) Xenogeneic transplantation of mouse bone marrow MSCs by testis net injection was successful, without immunoreaction. On the 1 st day after transplantation, MSCs only concentratively distributed in the medial slices, the nucleoli being light-yellow; On the 1 st and 3 rd day, MSCs dispersively distributed in the medial slices; On the 6th, 9th and 12th day, MSCs presented in all the slices of the three sites, some ranging tubally; On the 15th and 18th day, the fluorescence of MSCs weakened; On the 21 st day, the fluorescence of MSCs disappeared. CONCLUSION: Transplantation of mouse bone marrow MSCs into the xenogeneic testis by testis net injection is effective and feasible, without immunoreaction. MSCs can survive after transplantation.

Aberrant microRNA expression in peripheral plasma and mononuclear cells as specific blood-based biomarkers in schizophrenia patients.

Findings from multiple studies on microRNA (miRNA) expression profiling in schizophrenia patients have produced conflicting results. In order to investigate miRNA as specific biomarkers in the peripheral plasma and peripheral blood mononuclear cells (PBMC) of schizophrenia patients, expression levels of the nine most frequently reported schizophrenia-associated miRNA (miR-30e, miR-34a, miR-181b, miR-195, miR-346, miR-432, miR-7, miR-132 and miR-212) were examined in the peripheral plasma and PBMC in 25 schizophrenia patients and 13 healthy controls using quantitative real-time reverse transcription polymerase chain reaction. We observed significantly increased expressions of miR-132, miR-195, miR-30e and miR-7 in plasma samples (p<0.05 to p<0.001), and miR-212, miR-34a and miR-30e in PBMC samples (p<0.05 to p<0.01). Receiver operating characteristic curve analysis revealed that the area under the curve (AUC) of miR-30e in plasma was 0.767 (95% confidence interval [CI] 0.608-0.926) with sensitivity and specificity of 90.90% and 60.00% respectively, and the AUC of miR-30e in PBMC was 0.756 (95% CI 0.584-0.929) with sensitivity and specificity of 81.80% and 68.00%, respectively. Logistic regression analysis demonstrated that miR-30e in plasma was more sensitive to differentiate schizophrenia patients from normal controls than miR-30e in PBMC. Our findings indicate that miRNA expression is more significant in plasma than in PBMC, and suggest that miR-30e in plasma may be a more sensitive biomarker for schizophrenia diagnosis, although its aberrant expression can be detected in both plasma and PBMC.

Humoral immune responses in rabbits induced by an experimental inactivated severe acute respiratory syndrome coronavirus vaccine prepared from F69 strain.

BACKGROUND: The etiologic agent of severe acute respiratory syndrome (SARS) has been confirmed to be a novel coronavirus (CoV), namely SARS-CoV. Developing safe and effective SARS-CoV vaccines is essential for us to prevent the possible reemergence of its epidemic. Previous experiences indicate that inactivated vaccine is conventional and more hopeful to be successfully developed. Immunogenicity evaluation of an experimental inactivated SARS-CoV vaccine in rabbits was conducted and reported in this paper. METHODS: The large-scale cultured SARS-CoV F69 strain was inactivated with 0.4% formaldehyde and purified, then used as the immunogen combined with Freund's adjuvant. Eight adult New Zealand rabbits were immunized four times with this experimental inactivated vaccine. Twelve sets of rabbit serum were sampled from the third day to the seventy-fourth day after the first vaccination. The titers of specific anti-SARS-CoV IgG antibody were determined by indirect enzyme-linked immunosorbent assay, and the neutralizing antibody titers were detected with micro-cytopathic effect neutralization test. RESULTS: Rapid and potent humoral immune responses were induced by the inactivated SARS-CoV vaccine in all the eight test rabbits. Titers of both specific IgG antibody and neutralizing antibody peaked at about six weeks after first vaccination, with the maximum value of 1:81 920 and 1:20 480, respectively. After that, serum antibody levels remained at a plateau or had a slight decrease, though two boosters were given in the succedent 4 to 5 weeks. Cross neutralization response existed between SARS-CoV F69 strain and Z2-Y3 strain. CONCLUSIONS: The inactivated SARS-CoV vaccine made from F69 strain owns strong immunogenicity, and the cross neutralization response between the two different SARS-CoV strains gives a hint of the similar neutralizing epitopes, which provide stable bases for the development of inactivated SARS-CoV vaccines.

[E14 mouse embryonic stem cells differentiate into hepatocyt ESC].

OBJECTIVE: To investigate in vitro methods of inducing mouse embryonic stem cell(s) (ESC) into hepatocytes. METHODS: E14 mouse ESC were cultivated in suspension and plated to form aggregates, the embryoid bodies. They were allowed to outgrow on the plated culture with the stepwise addition of growth factors-- acidic fibroblast growth factor (aFGF), hepatocyte growth factor (HGF) and oncostatin M (OSM) into the culture medium. Morphology was investigated by phase contrast microscopy. Gene expressions of endodermal and liver specific mRNA were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Indocyanine green (ICG) uptake assay and periodic acid-Schiff reaction (PAS) were performed to assess the differentiation and function of the cells. RESULTS: Morphology analysis revealed a difference between ESC-derived hepatic cells and original ESC in that the former showed distinct round or polygonal shapes with clear boundaries, some arranged tightly in cords, while the latter grew in clones without clear boundaries between cells. Those ESC-derived hepatic cells expressed endodermal and liver specific genes mRNA--TTR, AAT, AFP, ALB, G6P and TAT. ICG uptake assay and PAS reaction were positive for those ESC-derived hepatic cells. The ICG positive cells were about 85.1% in number. CONCLUSION: ESC-derived hepatic cells possess characteristics of hepatocytes, which would promise the eventual clinical use of ESC in treating damaged liver tissues.