[A review on the effect of Claudin-18 on bronchopulmonary dysplasia in preterm infants].

Bronchopulmonary dysplasia (BPD) has the main manifestations of pulmonary edema in the early stage and characteristic alveolar obstruction and microvascular dysplasia in the late stage, which may be caused by structural and functional destruction of the lung epithelial barrier. The Claudin family is the main component of tight junction and plays an important role in regulating the permeability of paracellular ions and solutes. Claudin-18 is the only known tight junction protein solely expressed in the lung. The lack of Claudin-18 can lead to barrier dysfunction and impaired alveolar development, and the knockout of Claudin-18 can cause characteristic histopathological changes of BPD. This article elaborates on the important role of Claudin-18 in the development and progression of BPD from the aspects of lung epithelial permeability, alveolar development, and progenitor cell homeostasis, so as to provide new ideas for the pathogenesis and clinical treatment of BPD.

Proteomic analysis of Fasciola gigantica excretory and secretory products (FgESPs) interacting with buffalo serum of different infection periods by shotgun LC-MS/MS.

Fasciolosis, caused by Fasciola hepatica and Fasciola gigantica, is an important zoonotic disease in the world. It affects livestock, especially for sheep and cattle, causing major economic loss due to morbidity and mortality. Although the excretory and secretory products (ESPs) of F. hepatica have been relatively well studied, little is known about the interaction between the ESP and host, and the mechanism of the key proteins involved in interaction. In this study, buffaloes were infected by Fasciola gigantica, and infection serum was collected at three different periods (42dpi, 70dpi, and 98dpi). The interaction proteins were pulled down with three different period serum by Co-IP assay, respectively, and then identified by LC-MS/MS analysis. A number of proteins were identified; some of them related to the biological function of the parasite, while most of them the functions were unknown. For the annotated proteins, 13, 5, and 7 proteins were pulled down by the infected serum in 42dpi, 70dpi, and 98dpi, respectively, and 18 proteins could be detected in all three periods. Among them, 13 belong to the cathepsin family, 4 proteins related to glutathione S-transferase, and 3 proteins are calcium-binding protein; other proteins related to catalytic activity and cellular process. This study could provide new insights into the central role played by ESPs in the protection of F. gigantica from the host immune response. At the same time, our research provided material for further studies about the interaction between F. gigantica and host.

Complete mitochondrial genome of parasitic nematode Cylicocyclus nassatus and comparative analyses with Cylicocyclus insigne.

Cylicocyclus nassatus is a common and important parasite in the large intestine of equine. In this study, the complete mitochondrial (mt) genome sequence of C. nassatus was determined and comparatively analyzed with Cylicocyclus insigne. The mt genome size of C. nassatus was 13,846 bp, 18 bp longer than that of C. insigne. The circular mt genome includes 12 protein-coding genes, two rRNA genes, 22 tRNA genes and two non-coding regions. All the genes are transcribed in the same direction and gene arrangement is consistent with that of gene arrangement 3 (GA3). The overall sequence difference between the two complete mt genomes was 10.7%. For the 12 protein-coding genes, the comparison between C. nassatus and C. insigne revealed sequence divergence at both the nucleotide (6.3-13.0%) and amino acid (0.8-6.6%) levels. The nucleotide lengths of the 12 protein-coding genes were the same, except for cox3 which was longer in C. insigne. Phylogenetic analysis based on the concatenated amino acid sequence of the 12 protein-coding genes was performed using all the Strongylidae nematodes of the horse available in the GenBank. Phylogenetic analysis showed that C. nassatus and C. insigne clustered together with very high nodal support and the genus Cylicocyclus was closer to the genus Triodontophorus than to genus Strongylus. The mtDNA data determined in this study provides novel genetic markers for further studies on the identification, population genetics and molecular epidemiology of the genus Cylicocyclus.

Evaluation of protective immunity induced by DNA vaccination with genes encoding Toxoplasma gondii GRA17 and GRA23 against acute toxoplasmosis in mice.

Toxoplasma gondii, an obligatory intracellular protozoan, can cause serious public health problems and economic losses worldwide. Two novel dense granule proteins (GRA17 and GRA23) were recently identified as T. gondii-secreted proteins which are localized to the parasitophorous vacuole membrane (PVM) and can mediate the movement of small molecules between the host cell and parasitophorous vacuole (PV). In the present study, we evaluated the protective immunity induced by DNA vaccination with genes encoding GRA17 and GRA23 against acute toxoplasmosis in mice. Eukaryotic expressing plasmids pVAX-TgGRA17 and pVAX-TgGRA23 were constructed. Then, BALB/c mice were intramuscularly immunized with pVAX-TgGRA17, pVAX-TgGRA23, or pVAX-TgGRA17 + pVAX-TgGRA23 followed by challenge infection with the highly virulent RH strain of T. gondii. The specific immune responses and protective efficacy against T. gondii were examined by cytokine and serum antibody measurements, lymphocyte proliferation assays, flow cytometry of lymphocytes and the survival time after challenge. Our results showed that mice immunized with pVAX-TgGRA17, pVAX-TgGRA23, or pVAX-TgGRA17 + pVAX-TgGRA23 induced specific humoral and cellular responses, with higher level of IgG antibody, increased levels of Th1-type cytokines IFN-γ and IL-12 (p70), and CD3+CD4+CD8- and CD3+CD8+CD4- T cells, as well as prolonged survival time (9.1 ± 0.32 days for pVAX-TgGRA17, 10.8 ± 0.79 days for pVAX-TgGRA23, and 12.6 ± 2.55 days for pVAX-TgGRA17 + pVAX-TgGRA23) compared to the blank control (7.11 ± 0.33 days), PBS control (7.22 ± 0.44 days), and pVAX I control (7.11 ± 0.33 days). These results demonstrated that both TgGRA17 and TgGRA23 are potential vaccine candidates, TgGRA23 has a better immunogenicity, and co-immunization of pVAX-TgGRA17 and pVAX-TgGRA23 induces better protective efficacy.

Proteomic analysis of Fasciola hepatica excretory and secretory products (FhESPs) involved in interacting with host PBMCs and cytokines by shotgun LC-MS/MS.

Fasciola hepatica is a helminth parasite with a worldwide distribution, which can cause chronic liver disease, fasciolosis, leading to economic losses in the livestock and public health in many countries. Control is mostly reliant on the use of drugs, and as a result, drug resistance has now emerged. The identification of F. hepatica genes involved in interaction between the parasite and host immune system is utmost important to elucidate the evasion mechanisms of the parasite and develop more effective strategies against fasciolosis. In this study, we aimed to identify molecules in F. hepatica excretory and secretory products (FhESPs) interacting with the host peripheral blood mononuclear cells (PBMCs), Th1-like cytokines (IL2 and IFN-γ), and Th17-like cytokines (IL17) by Co-IP combined with tandem mass spectrometry. The results showed that 14, 16, and 9 proteins in FhESPs could bind with IL2, IL17, and IFN-γ, respectively, which indicated that adult F. hepatica may evade the host immune responses through directly interplaying with cytokines. In addition, nine proteins in FhESPs could adhere to PBMCs. Our findings provided potential targets as immuno-regulators, and will be helpful to elucidate the molecular basis of host-parasite interactions and search for new potential proteins as vaccine and drug target candidates.

Prevalence and risk factors of Cryptosporidium infection in farmed pigs in Zhejiang, Guangdong, and Yunnan provinces, China.

Cryptosporidiosis is caused by species of Cryptosporidium protozoa that can infect a wide range of host animals worldwide. However, data regarding Cryptosporidium infection in farmed pigs in subtropical areas in China is limited. Therefore, a total of 396 fecal samples were obtained from farmed pigs from Zhejiang (n = 124), Guangdong (n = 72), and Yunnan (n = 200) provinces, China, and were tested by PCR amplification of the small subunit (SSU) rRNA gene. The overall prevalence of Cryptosporidium in pigs was 17.68% (70/396), with 20.11% (36/179) in male pigs and 15.67% (34/217) in female pigs. Additionally, Cryptosporidium prevalence was 8.33% (6/72) in Guangdong province, 14.52% (18/124) in Zhejiang province, and 23.00% (46/200) in Yunnan province. A DNA sequence analysis of the SSU rRNA gene revealed that all of the isolates represented C. scrofarum. This is the first report of C. scrofarum infection in pigs in Guangdong and Yunnan provinces in subtropical areas of China. The results of the present study provide foundation data for control and prevention of Cryptosporidium infection in pigs in the study areas in China.

Complete Mitochondrial Genome of Echinostoma hortense (Digenea: Echinostomatidae).

Echinostoma hortense (Digenea: Echinostomatidae) is one of the intestinal flukes with medical importance in humans. However, the mitochondrial (mt) genome of this fluke has not been known yet. The present study has determined the complete mt genome sequences of E. hortense and assessed the phylogenetic relationships with other digenean species for which the complete mt genome sequences are available in GenBank using concatenated amino acid sequences inferred from 12 protein-coding genes. The mt genome of E. hortense contained 12 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 non-coding region. The length of the mt genome of E. hortense was 14,994 bp, which was somewhat smaller than those of other trematode species. Phylogenetic analyses based on concatenated nucleotide sequence datasets for all 12 protein-coding genes using maximum parsimony (MP) method showed that E. hortense and Hypoderaeum conoideum gathered together, and they were closer to each other than to Fasciolidae and other echinostomatid trematodes. The availability of the complete mt genome sequences of E. hortense provides important genetic markers for diagnostics, population genetics, and evolutionary studies of digeneans.

The complete mitochondrial genome of Oxyuris equi: Comparison with other closely related species and phylogenetic implications.

The equine pinworm Oxyuris equi (Nematoda: Oxyuridomorpha) is the most common horse nematode, has a worldwide distribution, and causes major economic losses. In the present study, the complete O. equi mitochondrial (mt) genome was sequenced, and the mt genome structure and organization were compared with those of other closely related pinworm species, Enterobius vermicularis and Wellcomia siamensis. The O. equi mt genome is a 13,641-bp circular DNA molecule that encodes 36 genes (12 protein-coding genes, 22 tRNAs, and two rRNAs) and one non-coding region, which is slightly shorter than that of E. vermicularis and W. siamensis. The O. equi mt gene arrangement was consistent with that of GA13-type E. vermicularis but it differs from GA12-type W. siamensis. Phylogenetic analyses using concatenated amino acid sequences of the 12 protein-coding genes with three different computational algorithms (maximum parsimony, maximum likelihood, and Bayesian inference) revealed that there were two distinct clades in Chromadorea nematodes that reflected infraorder. Spiruromorpha formed one clade, whereas Rhabditomorpha, Ascaridomorpha, and Oxyuridomorpha formed another clade. O. equi, E. vermicularis, and W. siamensis represent distinct but closely related species, which indicated that Oxyuridomorpha is paraphyletic. Sequencing the O. equi mt genome provides novel genetic markers for studying the molecular epidemiology and population genetics of pinworms.

The complete mitochondrial genome of Strongylus equinus (Chromadorea: Strongylidae): Comparison with other closely related species and phylogenetic analyses.

The roundworms of genus Strongylus are the common parasitic nematodes in the large intestine of equine, causing significant economic losses to the livestock industries. In spite of its importance, the genetic data and epidemiology of this parasite are not entirely understood. In the present study, the complete S. equinus mitochondrial (mt) genome was determined. The length of S. equinus mt genome DNA sequence is 14,545 bp, containing 36 genes, of which 12 code for protein, 22 for transfer RNA, and two for ribosomal RNA, but lacks atp8 gene. All 36 genes are encoded in the same direction which is consistent with all other Chromadorea nematode mtDNAs published to date. Phylogenetic analysis based on concatenated amino acid sequence data of all 12 protein-coding genes showed that there were two large branches in the Strongyloidea nematodes, and S. equinus is genetically closer to S. vulgaris than to Cylicocyclus insignis in Strongylidae. This new mt genome provides a source of genetic markers for the molecular phylogeny and population genetics of equine strongyles.

Levo-Tetrahydropalmatine Attenuates Bone Cancer Pain by Inhibiting Microglial Cells Activation.

OBJECTIVE: The present study is to investigate the analgesic roles of L-THP in rats with bone cancer pain caused by tumor cell implantation (TCI). METHODS: Thermal hyperalgesia and mechanical allodynia were measured at different time points before and after operation. L-THP (20, 40, and 60 mg/kg) were administrated intragastrically at early phase of postoperation (before pain appearance) and later phase of postoperation (after pain appearance), respectively. The concentrations of TNF-α, IL-1ß, and IL-18 in spinal cord were measured by enzyme-linked immunosorbent assay. Western blot was used to test the activation of astrocytes and microglial cells in spinal cord after TCI treatment. RESULTS: TCI treatment induced significant thermal hyperalgesia and mechanical allodynia. Administration of L-THP at high doses significantly prevented and/or reversed bone cancer-related pain behaviors. Besides, TCI-induced activation of microglial cells and the increased levels of TNF-α and IL-18 were inhibited by L-THP administration. However, L-THP failed to affect TCI-induced astrocytes activation and IL-1ß increase. CONCLUSION: This study suggests the possible clinical utility of L-THP in the treatment of bone cancer pain. The analgesic effects of L-THP on bone cancer pain maybe underlying the inhibition of microglial cells activation and proinflammatory cytokines increase.

Jolkinolide B from Euphorbia fischeriana Steud induces in human leukemic cells apoptosis via JAK2/STAT3 pathways.

Jolkinolide B from the roots of Euphorbia fischeriana Steud exhibits significant antitumor activities against several tumor lines. Previous study has shown that Jolkinolide B could induce apoptosis in human leukemia cells. However, the exact mechanism and signaling pathway involved in Jolkinolide B-induced apoptosis have not been fully elucidated. In the present study, we found that Jolkinolide B reduced cell viability and induced apoptosis in dose- and time-dependent manner in human leukemic HL-60 and THP-1 cells. The induction of apoptosis was accompanied by the downregulation of JAK2/STAT3. Our results also suggest that expression of Bcl-2 and mitochondrial cytochrome c was dosedependently reduced following Jolkinolide B-treated THP-1 and HL-60 cells, whereas Jolkinolide B up-regulated the expression of Bax and cytosolic cytochrome c. Moreover, we observed that Jolkinolide B treatment resulted in activation of caspase-3, -8, and -9. JSI-124, a STAT-3 inhibitor, was able to block the negative effect of Jolkinolide B on cell apoptosis. Taken together, our study for the first time suggests that Jolkinolide B is able to enhance apoptosis of human leukemic HL-60 and THP-1 cells, at least in part, through downregulation of JAK2/STAT3 and bcl-2, and upregulation of Bax and cytosolic cytochrome c. Moreover, the triggering of caspase-3, -8, and -9 activation mediated apoptotic induction.

Maternal exposure to sulfur dioxide before and after conception and the risk of hypospadias in offspring.

As far as we know, there have been no studies exploring the association between maternal sulfur dioxide (SO2 ) exposure and the risk of hypospadias in offspring. We aimed to evaluate this association during the 3 months before conception and the first trimester. A population-based case-control study was conducted in male infants, consisting of 348 cases of hypospadias and 4023 controls. Maternal exposure to SO2 , particulate matter with aerodynamic diameters ≤10 µm (PM10 ), and nitrogen dioxide (NO2 ) was assessed by averaging the concentrations recorded at all stations in the mother's city of residence. Air pollutants were tested for multicollinearity using variance inflation factor analysis. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by multivariable logistic regression models. SO2 exposure during the 3 months before conception was significantly associated with the risk of hypospadias (highest tertile: OR = 7.40, 95% CI: 3.54-15.62). When focusing on shorter exposure windows, similar associations were observed for SO2 exposure in the first and second month before and the first month after conception. In conclusion, maternal exposure to SO2 during the 3 months before and the first and second months after conception may increase the risk of hypospadias in offspring.

IL-18 Contributes to Bone Cancer Pain by Regulating Glia Cells and Neuron Interaction.

Glial cell hyperactivity has been proposed to be responsible for chronic pain, however, the mechanisms remain unclear. Interleukin (IL)-18, released from glial cells, has been reported to be involved in neuropathic pain. In this study, we investigated the role of IL-18 in bone cancer pain. Bone cancer pain was mimicked by injecting Walker-256 mammary gland carcinoma cells into the intramedullary space of the tibia in rats. Expression and location of IL-18 and the IL-18 receptor were tested. To investigate the contribution of IL-18 signaling to bone cancer pain, IL-18 binding protein and recombinant IL-18 were used. To investigate the mechanisms of glial cells effects, MK801, N-methyl-D-aspartate (NMDA) receptor inhibitor, and Src kinase-specific inhibitor PP1 were used. Tumor cell implantation (TCI) treatment increased expression of IL-18 and IL-18 receptor in spinal cord. The time course of IL-18 upregulation was correlated with TCI-induced pain behaviors. Blocking the IL-18 signaling pathway prevented and reversed bone cancer-related pain behaviors. Meanwhile, blocking IL-18 signaling also suppressed TCI-induced glial cell hyperactivity, as well as activation of GluN2B and subsequent Ca2+-dependent signaling. Spinal administration of recombinant IL-18 in naive rat induced significant mechanical allodynia, as well as GluN2B activation. However, intrathecal injection of MK801 failed to suppress recombinant IL-18-induced GluN2B phosphorylation, whereas Src kinase inhibitor PP1 significantly inhibited IL-18-induced GluN2B activation. IL-18-mediated glial-glia and glial-neuron interaction may facilitate bone cancer pain. Blocking IL-18 signaling may effectively prevent and/or suppress bone cancer pain. PERSPECTIVE: IL-18 signaling may be a new target for cancer pain therapy.

Immunization with Toxoplasma gondii GRA17 Deletion Mutant Induces Partial Protection and Survival in Challenged Mice.

Toxoplasmosis remains a world-threatening disease largely because of the lack of a fully effective vaccine. Here, we created a ΔGRA17 mutant by disrupting the virulence factor GRA17 using CRISPR-Cas9 method. Then, we tested whether ΔGRA17 tachyzoites can be used as a live-attenuated vaccine against acute, chronic, and congenital Toxoplasma gondii infection in mice. Immune response evoked by ΔGRA17 immunization suggested a sequential Th1 and Th2 T cell response, indicated by high levels of Th1 and a mixed Th1/Th2 cytokines at 28 and 70 days after immunization, respectively. ΔGRA17-mediated immunity fully protected mice against lethal infection with wild-type (wt) RH strain, heterologous challenge with PYS, and TgC7 strains of the Chinese ToxoDB#9 genotype, and T. gondii Pru strain. Although parasite cysts were detected in 8 out of 10 immunized mice, cyst burden in the brain was significantly reduced (P < 0.05) in immunized mice (53 ± 15 cysts/brain) compared to non-immunized mice (4,296 ± 687 cysts/brain). In respect to congenital infection, the litter size, survival rate, and body weight (BW) of pups born to ΔGRA17-immunized dams were not different compared to pups born to naïve control dams (P = 0.24). However, a marked reduction in the litter size (P < 0.001), survival rate, and BW (P < 0.01) of pups born to non-immunized and infected dams was detected. Also, immunized dams infected with type II Pru strain had significantly (P < 0.001) less cyst burden in the brain compared with non-immunized and infected dams. These findings show that immunization with ΔGRA17 strain evokes cell-mediated and neutralizing antibody responses and confers some degree of protection against challenge with homologous and heterologous virulent T. gondii strains.

Genetic variation between and within Triodontophorus brevicauda and Triodontophorus nipponicus revealed by analyses of mtDNA and rDNA gene sequences.

Triodontophorus spp. parasitizes the large intestine of equine, causing strongylid diseases. The present study assessed genetic variation in five gene regions within and between Triodontophorus brevicauda and Triodontophorus nipponicus from Heilongjiang Province and the Inner Mongolia Autonomous region. The five gene markers were three mitochondrial (mt) genes, cytochrome c oxidase subunit I (cox1), NADH dehydrogenase subunit 5 (nad5), cytochrome b (cytb); and two ribosomal RNA genes, the internal transcribed spacer 1 (ITS1) and the internal transcribed spacer 2 (ITS2). Partial (p) sequences of cox1, nad5, cytb and the complete ITS rDNA region were PCR amplified from individual nematodes, and the amplicons were subjected to sequencing in both directions. The size of the three mt genes is identical in both species: 761 bp (p cox1), 505 bp (pnad5) and 562 bp (pcytb); the length of the two ribosomal genes is different: 376 bp and 370 bp (ITS1), and 333 bp and 322 bp (ITS2), respectively. Intraspecific variation between T. brevicauda and T. nipponicus was 0-1.5% and 0-1.1% for pcox1, 0-2.0% and 0-2.0% for pnad5, 0-1.4% and 0-2.2% for pcytb, 0-0.8% and 0-1.1% for ITS1 and 0-0.9% and 0-2.2% for ITS2. Interspecific variation within the nematodes was 13.5-14.3% for pcox1, 15.5-18.7% for pnad5, 16.7-18.6% for pcytb, 11.5-13.1% for ITS1 and 16.0-18.4% for ITS2. Phylogenetic analyses based on the combined mt gene sequences, as well as with the ITS sequences, show each species forming a monophyletic group of individuals. However, samples of different species from the same geographical origin did not always cluster together. These results provide valuable information for further studies of systematics and population genetics of the genus Triodontophorus.

Occurrence of Enterocytozoon bieneusi in Donkeys (Equus asinus) in China: A Public Health Concern.

Enterocytozoon bieneusi is an important zoonotic parasite. It can infect virtually all animal species and has a global distribution. However, the prevalence of E. bieneusi in donkeys (Equus asinus) has only been reported in Algeria and Spain, and no information is available concerning genotypes of E. bieneusi in donkeys worldwide. In the present study, a total of 301 donkey fecal samples (48 from Jilin Province, 224 from Shandong Province and 29 from Liaoning Province) were collected and examined by PCR amplification of the internal transcribed spacer (ITS) region. The overall E. bieneusi prevalence was 5.3% (16/301), with 6.3% (3/48) in Jilin Province, 4.9% (11/224) in Shandong Province, and 6.9% (2/29) in Liaoning Province. Prevalence in different age groups ranged from 4.2 to 5.5%. E. bieneusi prevalence in donkeys sampled in different seasons varied from 4.2 to 6.5%. Altogether, four E. bieneusi genotypes were identified in this study, with two known genotypes (J and D) and two novel genotypes (NCD-1and NCD-2). Phylogenetic analysis revealed that genotypes D, NCD-1 and NCD-2 belonged to group 1, while the remaining genotype J was clustered into group 2. These findings revealed the occurrence of E. bieneusi in donkeys in China for the first time. Moreover, the present study also firstly genotyped the E. bieneusi in donkeys worldwide. These findings extend the distribution of E. bieneusi genotypes and provide baseline data for controlling E. bieneusi infection in donkeys, other animals and humans.

Functional Characterization of Rhoptry Kinome in the Virulent Toxoplasma gondii RH Strain.

Toxoplasma gondii is an obligatory intracellular apicomplexan protozoan which can infect any warm-blooded animal and causes severe diseases in immunocompromised individuals or infants infected in utero. The survival and success of this parasite require that it colonizes the host cell, avoids host immune defenses, replicates within an appropriate niche, and exits the infected host cell to spread to neighboring non-infected cells. All of these processes depend on the parasite ability to synthesis and export secreted proteins. Amongst the secreted proteins, rhoptry organelle proteins (ROPs) are essential for the parasite invasion and host cell manipulation. Even though the functions of most ROPs have been elucidated in the less virulent T. gondii (type II), the roles of ROPs in the highly virulent type I strain remain largely un-characterized. Herein, we investigated the contributions of 15 ROPs (ROP10, ROP11, ROP15, ROP20, ROP23, ROP31, ROP32, ROP33, ROP34, ROP35, ROP36, ROP40, ROP41, ROP46, and ROP47) to the infectivity of the high virulent type I T. gondii (RH strain). Using CRISPR-Cas9, these 15 ROPs genes were successfully disrupted and the effects of gene knockout on the parasite's ability to infect cells in vitro and BALB/c mice in vivo were investigated. These results showed that deletions of these ROPs did not interfere with the parasite ability to grow in cultured human foreskin fibroblast cells and did not significantly alter parasite pathogenicity for BALB/c mice. Although these ROPs did not seem to be essential for the acute infectious stage of type I T. gondii in the mouse model, they might have different functions in other intermediate hosts or play different roles in other life cycle forms of this parasite due to the different expression patterns; this warrants further investigations.

[Relationship between expression of aquaporin-1, -5 and pulmonary edema in hyperoxia-induced lung injury in newborn rats].

OBJECTIVE: Aquaporin (AQP) is a group of cell membrane transporting proteins. The study was designed to investigate the changes of AQP1 and AQP5 in the lung tissue under hyperoxia and their roles in pulmonary edema. METHODS: Two hundred newborn rats were randomized into different oxygen concentrations exposure: FiO2=0.80 (Experimental group 1), FiO2=0.60 (Experimental group 2), FiO2=0.40 (Experimental group 3) and FiO2=0.21 (Air control group). Rats were sacrificed at 1, 3, 5, 7 and 14 days after the beginning of experiment (10 rats each time point). The expressions of AQP1 and AQP5 were examined by Western Blot. The ratio of lung wet weight to lung dry weight (wet-to-dry weight ratio, W/D), and the protein content in bronchoalveolar lavage fluid (BALF) were measured. RESULTS: Compared with the Air control group, the W/D ratio and the protein content in BALF in the three experiment groups increased significantly and the increased extent was positively related to the duration and the oxygen concentration of hyperoxia-exposure. The expression of AQP1 in the experimental groups began to decrease at the 3rd day and significant differences were found at the 5th and the 7th days after hyperoxia-exposure compared with that in the Air control group (P < 0.05). The AQP1 expression was restored somewhat at the 14th day after hyperoxia-exposure, but it was still lower in the Experimental groups 1 and 2 than that in the Air control group (P < 0.05). The expression of AQP5 in the experimental groups were reduced compared with that in the Air control group 3 days after hyperoxia-exposure and the decrease of AQP5 expression was associated with duration of hyperoxia-exposure. The comparison among three experimental groups showed that the decrease of AQP1 and AQP5 expressions was associated with the concentration of hyperoxia-exposure. CONCLUSIONS: The expressions of AQP1 and AQP5 decreased in hyperoxia-induced lung injury and correlated with the severity of pulmonary edema.

[Nutrients Recovery on the Growth of Nitrogen and Phosphorus Starved Microcystis aeruginosa].

Microcystis in natural water bodies may frequently go through periods of nutrient limitation and then may recover when the limited nutrient becomes available. We investigated changes in cell physiology and expression of photosynthesis-related genes during the recovery of Microcystis aeruginosa from nitrogen starvation and phosphorus starvation with the method of 14C isotope and fluorescent quantitative PCR. Our results suggested that Microcystis cells relieved from N starvation and P starvation resumed growth within 24 h and displayed significantly higher growth rates than not-starved-cells in the first 48 h. Carbon production rates and the expression levels of photosynthesis-related genes all increased rapidly after relieving from N starvation and P starvation in different degrees, enabling the rapid recovery from nutrient starvation. However, N-starved cells can not resume their cellular activity to full capacity when N became available and the damage of N deficiency to M. aeruginosa was unrecoverable, whereas cellular activity of P-starved cells could recover to normal properties.

Sequencing and characterization of the complete mitochondrial genome from the pancreatic fluke Eurytrema pancreaticum (Trematoda: Dicrocoeliidae).

The trematode Eurytrema pancreaticum is a parasite of ruminant pancreatic and bile ducts, and also occasionally infects humans, causing eurytremiasis. In spite of it being a common fluke of cattle and sheep in endemic regions, little is known about the genomic resources of the parasite. We sequenced the complete mitochondrial (mt) genome of E. pancreaticum. It is 15,031 bp in size, and encodes 36 genes: 12 protein-coding genes, two ribosomal RNA genes, and 22 transfer RNA genes. The E. pancreaticum mt gene order is the same as that of Dicrocoelium chinensis and Dicrocoelium dendriticum, and all genes are transcribed in the same direction. Phylogenetic analysis based on the concatenated amino acid sequences of 12 protein-coding genes by Bayesian inference shows that E. pancreaticum is closely related to D. chinensis and other members of the family Dicrocoeliidae with strong posterior probability support. The E. pancreaticum mt genome should prove to be a useful resource for comparative mt genomic studies of digenetic trematodes, and will provide a rich source of DNA markers for studies into the systematics, epidemiology, and population genetics of this parasite and other digenean trematodes.