Inflammation inhibitors were remarkably up-regulated in plasma of severe acute respiratory syndrome patients at progressive phase

Severe acute respiratory syndrome (SARS) is a severe infectious disease that has affected many countries and regions since 2002. A novel member of the coronavirus, SARS-CoV, has been identified as the causative agent. However, the pathogenesis of SARS is still elusive. In this study, we used 2-D DIGE and MS to analyze the protein profiles of plasma from SARS patients, in the search for proteomic alterations associated with the disease progression, which could provide some clues to the pathogenesis. To enrich the low-abundance proteins in human plasma, two highly abundant proteins, albumin and IgG, were first removed. By comparing the plasma proteins of SARS patients with those of a normal control group, several proteins with a significant alteration were found. The up-regulated proteins were identified as alpha-1 acid glycoprotein, haptoglobin, alpha-1 anti-chymotrypsin and fetuin. The down-regulated proteins were apolipoprotein A-I, transferrin and transthyretin. Most of the proteins showed significant changes (up- or down-regulated) in the progressive phase of disease, and there was a trend back to normal level during the convalescent phase. Among these proteins, the alterations of fetuin and anti-chymotrypsin were further confirmed by Western blotting. Since all the up-regulated proteins identified above are well-known inflammation inhibitors, these results strongly suggest that the body starts inflammation inhibition to sustain the inflammatory response balance in the progression of SARS.     

Ectopic expression of an Ammopiptanthus mongolicus H+-pyrophosphatase gene enhances drought and salt tolerance in Arabidopsis

An orthologue of the vacuolar H⁺-pyrophosphatase (H⁺-PPase) gene, AmVP1, was isolated from a desert plant, Ammopiptanthus mongolicus (Leguminosae), by RACE-PCR. AmVP1 has a total length of 2,875?bp, with an open reading frame of 2,316?bp, which encodes a predicted polypeptide of 771 amino acids. Sequence analysis revealed that it has high similarity with the VP1 proteins from other plants. AmVP1 was strongly induced by drought stress, but only responded initially to a salt stress. In addition, a 1.8?kb upstream sequence of AmVP1 was isolated from the genomic DNA of A. mongolicus by TAIL-PCR. Cis-element as well as promoter prediction analysis indicated that it contained three promoter sequences and more than 50 cis-elements. Heterologous expression of AmVP1 in the yeast mutant ena1 could partially suppress its hypersensitivity to NaCl. Over-expressing AmVP1 resulted in enhanced tolerances to both drought and salt stresses in transgenic Arabidopsis plants. The transgenic plants accumulated more sodium and potassium in their leaves after salt stress, and retained more water while producing less malondialdehyde during drought stress. A comparative study of salt tolerance between AtVP1 (an H⁺-PPase from Arabidopsis) and AmVP1 transgenic Arabidopsis suggested that the efficiency of AmVP1 is more than threefold higher than AtVP1. Our work suggested that AmVP1 functioned as a typical VP1 gene, but might be a more efficient orthologue than AtVP1 and therefore a valuable gene for improving plant salt and drought tolerances.     

Metabolic Coupling Determines the Activity: Comparison of 11β-Hydroxysteroid Dehydrogenase 1 and Its Coupling between Liver Parenchymal Cells and Testicular Leydig Cells

Background

11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) interconverts active 11β-hydroxyl glucocorticoids and inactive 11keto forms. However, its directionality is determined by availability of NADP+/NADPH. In liver cells, 11β-HSD1 behaves as a primary reductase, while in Leydig cells it acts as a primary oxidase. However, the exact mechanism is not clear. The direction of 11β-HSD1 has been proposed to be regulated by hexose-6-phosphate dehydrogenase (H6PDH), which catalyzes glucose-6-phosphate (G6P) to generate NADPH that drives 11β-HSD1 towards reduction.

Methodology

To examine the coupling between 11β-HSD1 and H6PDH, we added G6P to rat and human liver and testis or Leydig cell microsomes, and 11β-HSD1 activity was measured by radiometry.

Results and Conclusions

G6P stimulated 11β-HSD1 reductase activity in rat (3 fold) or human liver (1.5 fold), but not at all in testis. S3483, a G6P transporter inhibitor, reversed the G6P-mediated increases of 11β-HSD1 reductase activity. We compared the extent to which 11β-HSD1 in rat Leydig and liver cells might be coupled to H6PDH. In order to clarify the location of H6PDH within the testis, we used the Leydig cell toxicant ethane dimethanesulfonate (EDS) to selectively deplete Leydig cells. The depletion of Leydig cells eliminated Hsd11b1 (encoding 11β-HSD1) expression but did not affect the expression of H6pd (encoding H6PDH) and Slc37a4 (encoding G6P transporter). H6pd mRNA level and H6PDH activity were barely detectable in purified rat Leydig cells. In conclusion, the availability of H6PDH determines the different direction of 11β-HSD1 in liver and Leydig cells.     

Development of a New Risk Score for Incident Type 2 Diabetes Using Updated Diagnostic Criteria in Middle-Aged and Older Chinese

Type 2 diabetes mellitus (T2DM) reaches an epidemic proportion among adults in China. However, no simple score has been created for the prediction of T2DM incidence diagnosed by updated criteria with hemoglobin A1c (HbA1c) ≥6.5% included in Chinese. In a 6-year follow-up cohort in Beijing and Shanghai, China, we recruited a total of 2529 adults aged 50–70 years in 2005 and followed them up in 2011. Fasting plasma glucose (FPG), HbA1c, and C-reactive protein (CRP) were measured and incident diabetes was identified by the recently updated criteria. Of the 1912 participants without T2DM at baseline, 924 were identified as having T2DM at follow-up, and most of them (72.4%) were diagnosed using the HbA1c criterion. Baseline body mass index, FPG, HbA1c, CRP, hypertension, and female gender were all significantly associated with incident T2DM. Based upon these risk factors, a simple score was developed with an estimated area under the receiver operating characteristic curve of 0.714 (95% confidence interval: 0.691, 0.737), which performed better than most of existing risk score models developed for eastern Asian populations. This simple, newly constructed score of six parameters may be useful in predicting T2DM in middle-aged and older Chinese.     

Post-treatment follow-up study of abdominal cystic echinococcosis in tibetan communities of northwest Sichuan Province, China

Background

Human cystic echinococcosis (CE), caused by the larval stage of Echinococcus granulosus, with the liver as the most frequently affected organ, is known to be highly endemic in Tibetan communities of northwest Sichuan Province. Antiparasitic treatment with albendazole remains the primary choice for the great majority of patients in this resource-poor remote area, though surgery is the most common approach for CE therapy that has the potential to remove cysts and lead to complete cure. The current prospective study aimed to assess the effectiveness of community based use of cyclic albendazole treatment in Tibetan CE cases, and concurrently monitor the changes of serum specific antibody levels during treatment.

Methodology/Principal Findings

Ultrasonography was applied for diagnosis and follow-up of CE cases after cyclic albendazole treatment in Tibetan communities of Sichuan Province during 2006 to 2008, and serum specific IgG antibody levels against Echinococcus granulosus recombinant antigen B in ELISA was concurrently monitored in these cases. A total of 196 CE cases were identified by ultrasound, of which 37 (18.9%) showed evidence of spontaneous healing/involution of hepatic cyst(s) with CE4 or CE5 presentations. Of 49 enrolled CE cases for treatment follow-up, 32.7% (16) were considered to be cured based on B-ultrasound after 6 months to 30 months regular albendazole treatment, 49.0% (24) were improved, 14.3% (7) remained unchanged, and 4.1% (2) became aggravated. In general, patients with CE2 type cysts (daughter cysts present) needed a longer treatment course for cure (26.4 months), compared to cases with CE1 (univesicular cysts) (20.4 months) or CE3 type (detached cyst membrane or partial degeneration of daughter cysts) (9 months). In addition, the curative duration was longer in patients with large (>10 cm) cysts (22.3 months), compared to cases with medium (5–10 cm) cysts (17.3 months) or patients with small (<5 cm) cysts (6 months). At diagnosis, seven (53.8%) of 13 cases with CE1 type cysts without any previous intervention showed negative specific IgG antibody response to E. granulosus recombinant antigen B (rAgB). However, following 3 months to 18 months albendazole therapy, six of these 7 initially seronegative CE1 cases sero-converted to be specific IgG antibody positive, and concurrently ultrasound scan showed that cysts changed to CE3a from CE1 type in all the six CE cases. Two major profiles of serum specific IgG antibody dynamics during albendazole treatment were apparent in CE cases: (i) presenting as initial elevation followed by subsequent decline, or (ii) a persistent decline. Despite a decline, however, specific antibody levels remained positive in most improved or cured CE cases.

Conclusions

This was the first attempt to follow up community-screened cystic echinococcosis patients after albendazole therapy using ultrasonography and serology in an endemic Tibetan region. Cyclic albendazole treatment proved to be effective in the great majority of CE cases in this resource-poor area, but periodic abdominal ultrasound examination was necessary to guide appropriate treatment. Oral albendazole for over 18 months was more likely to result in CE cure. Poor drug compliance resulted in less good outcomes. Serology with recombinant antigen B could provide additional limited information about the effectiveness of albendazole in CE cases. Post-treatment positive specific IgG antibody seroconversion, in initially seronegative, CE1 patients was considered a good indication for positive therapeutic efficacy of albendazole.     

Identification of an AtCRN1-like chloroplast protein BeCRN1 and its distinctive role in chlorophyll breakdown during leaf senescence in bamboo (Bambusa emeiensis ‘Viridiflavus’)

CRN1/PPH/NYC3 is one of the key genes responsible for chlorophyll degradation during senescence in both Arabidopsis and rice. In this study, BeCRN1 and its promoter, BeCRN1p, were isolated from, Bambusa emeiensis ‘Viridiflavus’, a bamboo variety, for the first time. BeCRN1 consists of 1,646 bp, with an open reading frame of 1,473 bp, encoding a predicted polypeptide of 490 amino acids. Besides, BeCRN1 contained 5 exons and 4 introns, and harbored a distinctive microsatellite in the fourth intron. Differences in BeCRN1p are observed primarily in the AtCRN1 promoter, while sharing similar cis element composition with the rice CRN1 promoter. BeCRN1 is localized within the chloroplast, and it is strongly induced by senescence signals. Although constitutive overexpression of BeCRN1 in crn1 has reversed the stay-green phenotype of crn1 to the wild type phenotype, its promoter has failed to do so with AtCRN1 following dark treatment. The efficiency of BeCRN1p is only about one-third of that of the AtCRN1 promoter.     

A highly sensitive fluorescence sensor based on lucigenin/chitosan/SiO2 composite nanoparticles for microRNA detection using magnetic separation

In this paper, a convenient reverse‐phase microemulsion method for the synthesis of SiO₂ nanoparticles (NPs) by simply introducing the chitosan and fluorescent dye of lucigenin during the formation reaction of SiO₂ NPs was proposed. Addition of chitosan can make the SiO₂ NPs porous, and increases lucigenin molecule incorporation into chitosan/SiO₂ NPs nanopores based on electrostatic interaction and supermolecular forces. Therefore, fluorescence quantum yield of the lucigenin/chitosan/SiO₂ composite nanoparticles was increased by introduction of chitosan and compared with lucigenin/SiO₂ NPs without chitosan. Because the number of negative charges carried when using single‐stranded DNA (ssDNA) was different from that of double‐stranded DNA (dsDNA), the numbers of lucigenin/chitosan/SiO₂ composite nanoparticles with positive charge adsorbed using ssDNA or dsDNA were different. Consequently, fluorescence intensity caused using ssDNA or dsDNA/miRNA was clearly discriminative. With increase in target DNA/miRNA concentration, the difference in fluorescence intensity also increased, resulting in a good linear relationship between fluorescence intensity sensitizing value and target miRNA concentrations. Therefore, a new fluorescence analysis method for direct detection of let‐7a in human gastric cancer cell samples without enzyme, label free and no immobilization was established using lucigenin/chitosan/SiO₂ composite nanoparticles as a DNA hybrid indicator. The proposed method had high sensitivity and selectivity, low cost and the detection limit was 10 fM (S/N = 3).