Altitudinal patterns of plant species richness on the Baekdudaegan Mountains, South Korea: mid-domain effect, area, climate, and Rapoport’s rule

We studied the altitudinal patterns of plant species richness and examined the effects of geometric constraints, area, and climatic factors on the observed richness patterns along the ridge of the Baekdudaegan Mountains, South Korea. Rapoport’s altitudinal rule was evaluated by examining the relationship between altitudinal range size and midpoint. We also examined the latitudinal effect on species richness. Plant data were collected from 1,100 plots along a 200–1,900 m altitudinal gradient along the ridge of the Baekdudaegan. A total of 802 plant species from 97 families and 342 genera were found. The altitudinal patterns of plant species richness along the ridge of the Baekdudaegan depicted distinctly hump-shaped patterns, although the absolute altitudes of the richness peaks vary somewhat among plant groups. While the mid-domain effect (MDE) was the most powerful explanatory variable in simple regression models, species richness was also associated with climatic factors, especially mean annual precipitation (MAP) and temperature (MAT) in multiple regression models. The relative importance of the MDE and climatic factors were different among plant groups. The MDE was more important for woody plants and for large-ranged species, whereas climatic factors were better predictors for total and herbaceous plants and for small-ranged species. Rapoport’s altitudinal rule and a latitudinal effect on species richness were not supported. Our study suggests that a combined interaction of the MDE and climatic factors influences species richness patterns along the altitudinal gradient of the Baekdudaegan Mountains, South Korea.     

Development of rRNA-targeted probes for detection of Prorocentrum micans (Dinophyceae) using whole cell in situ hybridization

Prorocentrum is a common dinoflagellate genus along the Chinese seacoast, which frequently causes harmful algal blooms. Efforts to understand and prevent blooms caused by these harmful species require the development of methods for rapid and precise identification and quantification so that an adequate early warning of harmful algal blooms may be given. Here, we report the development and application of rRNA-targeted oligonucleotide probes for fluorescence in situ hybridization (FISH) to aid in the detection of Prorocentrum micans. The hypervariable D1–D2 regions of a large subunit rDNA of a strain isolated from East China Sea identified as P. micans were first sequenced to design species-specific probes. Analysis of sequences identified as P. micans and deposited in GenBank revealed significant base differences among them and phylogenetic analyses revealed multiple clades within the taxon P. micans. Thus, it is likely that more than one taxonomic and genetically distinct entity has been identified as P. micans, if not misidentified. A series of probes were identified to one of these clades and tested for their specificity. Second, whole cell in situ hybridization procedures were established and the optimal probes were screened among the candidate probes. Next, cross-reactivity was performed to test the specificity of the probes and the detection reliability under various culture conditions, including different nutrient levels, temperatures, and light intensities. Finally, an improved protocol for natural samples was applied to the field material. The designed rRNA-targeted probe was specific, showing no cross-reactivity with other microalgae. The optimized detection protocol could be completed within 1.5 h. All target cells were speculated to be identified during all stages of their whole growth cycle under different culture conditions because the difference in fluorescence intensities throughout the experiment was not significant (p?>?0.05). The cell densities determined by FISH and light microscopy (LM) were comparable, without any significant difference (p?>?0.05) between them. In general, the established FISH probe was promising for specific, rapid, precise detection of a selected set of P. micans in natural samples and served as a good detection model for other Prorocentrum in the future.     

Human extracellular superoxide dismutase (EC-SOD) expression in transgenic chicken

Extracellular superoxide dismutase (EC-SOD) is a metalloprotein and functions as an antioxidant enzyme. In this study, we used lentiviral vectors to generate transgenic chickens that express the human EC-SOD gene. The recombinant lentiviruses were injected into the subgerminal cavity of freshly laid eggs. Subsequently, the embryos were incubated to hatch using phases II and III of the surrogate shell ex vivo culture system. Of 158 injected embryos, 16 chicks (G0) hatched and were screened for the hEC-SOD by PCR. Only 1 chick was identified as a transgenic bird containing the transgene in its germline. This founder (G0) bird was mated with wild-type hens to produce transgenic progeny, and 2 transgenic chicks (G1) were produced. In the generated transgenic hens (G2), the hEC-SOD protein was expressed in the egg white and showed antioxidant activity. These results highlight the potential of the chicken for production of biologically active proteins in egg white. [BMB Reports 2013; 46(8): 404-409]     

Association of human leukocyte antigen E polymorphism with human cytomegalovirus reactivation in Chinese burn patients

The seroprevalence of human cytomegalovirus （HCMV） in adults increased steadily from 55% in developed countries to over 90% in developing countries like China [1]. As all her- pesviruses, HCMV establishes lifelong latency after primary infection. In immunocompetent individuals, host immune responses prevent the development of overt HCMV diseases. However, in immunoeompromised people who suffer from burn injuries, HCMV reactivation has been shown to lead to significant diseases with considerable morbidity and mortal- ity [2-4]. Recently, increasing evidence has suggested that HCMV reactivation might have been considerably underesti- mated in burn patients [5,6]. Review of the available litera- ture identifies 〉50% of HCMV antibody-positive burn patients may reactivate this virus [5,6]. Although the exact mechanisms of HCMV reactivation are still not clearly under- stood, the immune system and host genetics are thought to be the non-behavioral factors determining the acquisition of a reactivation.     

Quantitative analysis of site-specific N-glycans on sera haptoglobin βchain in liver diseases

The site-specific characterization of N-glycans in glycopro- teins with the potential of clinical application is important. In our previous report, the overall N-glycans of sera haptoglobin （Hp） β chain were found to be different in liver diseases. Hp β chain contains four potential sites of N-glycosylation. In this study, we investigated the potential change of N-glycans on Hp β chain in a site-specific fashion. Sera Hp β chain in healthy individuals as well as patients with hepatitis B virus （HBV）, liver cirrhosis （LC） and hepatocellular carcinoma （HCC） were purified, digested and subjected to liquid chromatography-electro- spray ionization-higher energy collision dissociation mass spectrometry, which allowed identification and structure determination of the glycopeptide, as well as the relative quantification of glycans present on each glycopeptide. The quantitative results revealed that the sialylation of NLFLN207HSEN211 ATAK and the fucosylated structure at all glycopeptides increased significantly in LC and HCC patients compared with those in HBV patients and healthy individuals. A set of different N-glycan patterns of Hp β chain in various liver diseases has been determined. Thus, the sialylated and fucosylated glycoforms of Hp β chain might be related to early hepatocarcinogenesis and also might be useful as novel differential markers for LC and HCC patients.     

Dynamic Changes in Endothelial Cell Adhesion Molecule Nepmucin/CD300LG Expression under Physiological and Pathological Conditions

Vascular endothelial cells often change their phenotype to adapt to their local microenvironment. Here we report that the vascular endothelial adhesion molecule nepmucin/CD300LG, which is implicated in lymphocyte binding and transmigration, shows unique expression patterns in the microvascular endothelial cells of different tissues. Under physiological conditions, nepmucin/CD300LG was constitutively and selectively expressed at the luminal surface of the small arterioles, venules, and capillaries of most tissues, but it was only weakly expressed in the microvessels of the splenic red pulp and thymic medulla. Furthermore, it was barely detectable in immunologically privileged sites such as the brain, testis, and uterus. The nepmucin/CD300LG expression rapidly decreased in lymph nodes receiving acute inflammatory signals, and this loss was mediated at least in part by TNF-α. It was also down-regulated in tumors and tumor-draining lymph nodes, indicating that nepmucin/CD300LG expression is negatively regulated by locally produced signals under these circumstances. In contrast, nepmucin/CD300LG was induced in the high endothelial venule-like blood vessels of chronically inflamed pancreatic islets in an animal model of non-obese diabetes. Interestingly, the activated CD4⁺ T cells infiltrating the inflamed pancreas expressed high levels of the nepmucin/CD300LG ligand(s), supporting the idea that nepmucin/CD300LG and its ligand interactions are locally involved in pathological T cell trafficking. Taken together, these observations indicate that the nepmucin/CD300LG expression in microvascular endothelial cells is influenced by factor(s) that are locally produced in tissues, and that its expression is closely correlated with the level of leukocyte infiltration in certain tissues.     

Differential Beta-Band Event-Related Desynchronization during Categorical Action Sequence Planning

A primate study reported the existence of neurons from the dorso-lateral prefrontal cortex which fired prior to executing categorical action sequences. The authors suggested these activities may represent abstract level information. Here, we aimed to find the neurophysiological representation of planning categorical action sequences at the population level in healthy humans. Previous human studies have shown beta-band event-related desynchronization (ERD) during action planning in humans. Some of these studies showed different levels of ERD according to different types of action preparation. Especially, the literature suggests that variations in cognitive factors rather than physical factors (force, direction, etc) modulate the level of beta-ERD. We hypothesized that the level of beta-band power will differ according to planning of different categorical sequences. We measured magnetoencephalography (MEG) from 22 subjects performing 11 four-sequence actions - each consisting of one or two of three simple actions - in 3 categories; ‘Paired (ooxx)’, ‘Alternative (oxox)’ and ‘Repetitive (oooo)’ (‘o’ and ‘x’ each denoting one of three simple actions). Time-frequency representations were calculated for each category during the planning period, and the corresponding beta-power time-courses were compared. We found beta-ERD during the planning period for all subjects, mostly in the contralateral fronto-parietal areas shortly after visual cue onset. Power increase (transient rebound) followed ERD in 20 out of 22 subjects. Amplitudes differed among categories in 20 subjects for both ERD and transient rebound. In 18 out of 20 subjects ‘Repetitive’ category showed the largest ERD and rebound. The current result suggests that beta-ERD in the contralateral frontal/motor/parietal areas during planning is differentiated by the category of action sequences.     

Identification of HSP90 as Potential Biomarker of Biliary Atresia Using Two-Dimensional Electrophoresis and Mass Spectrometry

Biliary atresia (BA) is a devastating cholestatic liver disease targeting infants. Current diagnosis depends on surgical exploration of the biliary tree. The aim of the present study was to identify potential biomarkers for the diagnosis of biliary atresia (BA). Two-dimensional electrophoresis was utilized for the identification of proteins that were differentially expressed in liver biopsies of 20 BA patients and 12 infants with non-BA neonatal cholestasis (NC) as controls. Using mass spectrometry, we identified 15 proteins with expressions significantly altered. Out of the 15 proteins identified, heat shock protein (HSP) 90 was the most significantly altered and was down-regulated in BA samples compared to NC samples using immunoblotting analysis. Our findings suggest that HSP90 might be a potential biomarker for the diagnosis of BA and may be used for monitoring further development and therapy for BA. This study demonstrated that a comprehensive strategy of proteomic identification combined with further validation should be adopted in biomarker discovery.