The influence of repetitive thermal stresses on the dominance of reef-building Acropora spp. (Scleractinia) on coral reefs of the Maldive Islands

The distribution and size-age structure of Acropora corals were studied in two Maldivian atolls that differ in their geographic position and sea surface temperature regimes. The frequency and strength of thermal anomalies for the last 2 decades had a significant influence on the abundance, mortality rates, and age structures of acroporid communities. The long-term temperature amplitude was higher and the maxima were more pronounced in the northernmost Ihavandippolu Atoll than those in the equatorial South Huvadhoo Atoll. These differences resulted in a 10.4% mean cover of Acropora at Ihavandippolu Atoll, whereas the Acropora cover in the South Huvadhoo Atoll reached 59.5%. In the northern atoll, the coral mortality rate after the 2010 thermal anomaly was 3 times higher than that in the southern atoll. Younger acroporid colonies (up to 2 years old) dominated the northern atoll reefs, while the southern atoll showed a high proportion of older mature colonies. In both atolls, healthy table colonies of Acropora cytherea with a disk diameter greater than 2 m were observed that apparently survived three thermal anomalies since 1998. The mechanisms of acclimatization of Acropora and the prospects for its dominance in the Maldives under changing environmental conditions are discussed.     

Transplantation and immunoincompatibility reactions among reef-building corals

Intracolony or syngeneic transplants of pieces of living coral, either occurring naturally on reefs or produced experimentally, were consistently compatible. In contrast, intercolony allografts performed extensively inAcropora formosa and inPorites andrewsii were incompatible, as were allografts occurring naturally in additional species observed in reef communities. Diverse interspecific combinations of coral xenografts generally displayed greater incompatibilities. Four levels of immuno-reactivity, with manifestations ranging from mild to severe, were distinguishable as follows: a) contact avoidance reactions, b) allogeneic contact incompatibility, c) chronic xenogeneic incompatibility, and d) acute interspecific aggression.Allogeneic incompatibility, most studied inA. formosa, was characterized by soft tissue contact avoidance wherever possible; absence of tissue death despite extensive enforced contact (18–20 days); and late interfacial cementation terminating allogeneic soft tissue contact. The properties ofchronic xenogeneic incompatibility as found in diverse species combinations, are slow onset (>7 days), bidirectional or unidirectional killing in contact zones, and short-range or localized effectiveness.Acute interspecific aggression initiated byFungia fungites as a dominant “aggressor ” is distinguished by early occurrence (2–7 days) and unidirectional contact killing. The presence or absence of these acute xenogeneic reactions sharply discriminated between species within each of the generaAcropora, Pocillopora, andPorites. No hierarchy of aggressive interactions was evident at the generic level.     

Apparent Reduction of ADAM10 in Scrapie-Infected Cultured Cells and in the Brains of Scrapie-Infected Rodents

It has been described that A disintegrin and metalloproteinase (ADAM10) may involve in the physiopathology of prion diseases, but the direct molecular basis still remains unsolved. In this study, we confirmed that ADAM10 was able to cleave recombinant human prion protein in vitro. Using immunoprecipitation tests (IP) and immunofluorescent assays (IFA), reliable molecular interaction between the native cellular form of PrP (PrP^C) and ADAM10 was observed not only in various cultured neuronal cell lines but also in brain homogenates of healthy hamsters and mice. Only mature ADAM10 (after removal of its prodomain) molecules showed the binding activity with the native PrP^C. Remarkably more prion protein (PrP)-ADAM10 complexes were detected in the membrane fraction of cultured cells. In the scrapie-infected SMB cell model, the endogenous ADAM10 levels, especially the mature ADAM10, were significantly decreased in the fraction of cell membrane. IP and IFA tests of prion-infected SMB-S15 cells confirmed no detectable PrP-ADAM10 complex in the cellular lysates and PrP-ADAM10 co-localization on the cell surface. Furthermore, we demonstrated that the levels of ADAM10 in the brain homogenates of scrapie agent 263K-infected hamsters and agent ME7-infected mice were also almost diminished at the terminal stage, showing time-dependent decreases during the incubation period. Our data here provide the solid molecular basis for the endoproteolysis of ADAM10 on PrP molecules and interaction between ADAM10 and PrP^C. Obvious loss of ADAM10 during prion infection in vitro and in vivo highlights that ADAM10 may play essential pathophysiological roles in prion replication and accumulation.     

Post Bleaching Assessment of Corals in Andaman and Nicobar Islands

Reefs of Andaman and Nicobar Islands harbour 418 species of scleractinian corals spread over an area of 2,000 km². In April to May, 2010, due to the delayed onset of the southwest monsoon the sea surface temperature of the coastal and oceanic region increased to 31.7 °C in respect to the earlier record of maximum 29.0 °C during the said period. This resulted in mass bleaching of hermatypic corals during May, 2010. Rapid under water surveys have been conducted in reefs of Andaman and Nicobar Islands to assess the health of corals between May 2010 and August 2011. It is estimated that 76.62 ± (SD) 10.83 % of coral species are bleached up to a water depth of 10–15 m. Species from the genus Acropora appeared more susceptible to bleaching than those belong to the genus Porites. During the month of June 2010 the sea surface temperature was reduced to 29 °C perhaps due to the rainfall which stimulated rebuilding of zooxanthellae population in bleached corals. Recovery of 85.54 ± (SD) 6.33 % of bleached corals was seen during the study period of 11 months after the bleaching event. Porites spp. showed a high recovery rate, while Acropora spp. had the highest mortality rate. Coral mortality can have profound ecological and socio-economical implications and highlights the need for sustained monitoring for coral reef conservation in India. Hence, steps must be taken to improve management tools to protect these resources of global significance.     

Effect of habitat characteristics on the distribution and abundance of damselfish within a Red Sea reef

For coral reef fish with an obligate relationship to their habitat, like Pomacentrid damselfish, choosing a suitable home amongst the reef structure is key to survival. A surprisingly small number of studies have examined patterns in adult damselfish distributions compared to other ontogenetic phases. The aim of this study was to determine which reef and coral colony characteristics explained adult damselfish distribution patterns in a Red Sea reef. The characteristics investigated were reef type (continuous or patchy), coral species (seven species of Acropora), and coral morphology (coral size and branching density). The focal damselfish species were Dascyllus aruanus, D. marginatus, Chromis viridis, and C. flavaxilla. Occupancy (presence or absence of resident damselfish), group size and fish species richness were not significantly different between the seven Acropora species. However, within each coral species, damselfish were more likely to occupy larger coral colonies than smaller coral colonies. Occupancy rates were also higher in patchy reef habitats than in continuous sections of the reef, probably because average coral colony size was greater in patchy reef type. Fish group size increased significantly with coral colony volume and with larger branch spacing. Multi-species groups of fish commonly occurred and were increasingly likely with reduced branching density and increased coral size.     

Polymorphism of DNA Repair Gene xrcc1 and Lung Cancer Risk

The current large-scale meta-analysis was performed to reach a reliable conclusion on the association between X-ray repair cross-complementing 1 (xrcc1) rs1799782 and the development of lung cancer. Studies that investigated the association between rs1799782 and lung cancer risk were identified by searching PubMed. We calculated odds ratio (OR) with corresponding 95 % confidence interval (CI) for Trp/Trp vs Arg/Arg, Trp/Trp + Arg/Trp vs Arg/Arg, and Trp/Trp vs Arg/Trp + Arg/Arg contrast models. Combining all 25 studies, we yielded three summary ORs: 1.07 (95 % CI 0.92–1.23) for Trp/Trp vs Arg/Arg, 0.93 (95 % CI 0.87–1.00) for Trp/Trp + Arg/Trp vs Arg/Arg, and 1.08 (95 % CI 0.94–1.25) for Trp/Trp vs Arg/Trp + Arg/Arg, suggesting rs1799782 was not associated with overall risk of lung cancer. Strikingly, a significantly deceased risk was found among Caucasian populations (Trp/Trp + Arg/Trp vs Arg/Arg, OR = 0.86, 95 % CI 0.76–0.97). This study confirms that xrcc1 rs1799782 may lower the risk of lung cancer among Caucasians.     

Mechanism of bFGF-binding Peptide Reversing Adriamycin Resistance in Human Gastric Cancer Cells

Development of drug resistance is a challenging problem in cancer chemotherapy. It has been shown that basic fibroblast growth factor (bFGF) plays an important role in an epigenetic mechanism of drug resistance. We have isolated a bFGF binding peptide P7 with inhibitory activity against bFGF-induced proliferation of human gastric cancer cells by screening a phage display library. In this study, we found that P7 peptide also has efficacy of reversing bFGF-induced resistance to Adriamycin (ADM) in human gastric cancer cells. Further investigations with SGC-7901 cells revealed that inhibition of Akt activation triggered by bFGF, and reversal of bFGF-induced up-regulation of Bcl-2 and XIAP and down-regulation of Bax, contribute to P7 peptide counteracting the anti-apoptotic effect of bFGF, and further reversing bFGF-induced resistance to ADM. The results suggested that the bFGF-binding peptide may have therapeutic potential of drug resistance in gastric cancer.     

Effects of colony size and polyp position on polyp fecundity in the scleractinian coral genus Acropora

This study examined the effects of colony size and polyp position on six variables of polyp fecundity [egg number, egg size, total egg volume, total testis volume, total gonad volume, and gonad ratio (egg volume/testis volume)] in three tabular Acropora corals (Scleractinia), A. hyacinthus, A. japonica, and A. solitaryensis. Samples were collected from various colony sizes (n = 21–30 colonies species^?1), just before the predicted spawning at Kochi, Japan, in 2009. Five replicate polyps were sampled at three positions (center, middle, and outer) from the center to the marginal area in each tabular colony. Results indicated effects of colony size and polyp position on both male and female gonads polyp^?1. A positive effect of colony size was observed on variables of female gonads polyp^?1 (egg number, total egg volume) in A. hyacinthus only, while the positive effect on the variable of male gonads polyp^?1 (total testis volume) was common in all Acropora species, with total testis volume polyp^?1 increasing 2–4-fold from the small (200–400 cm²) to the large size class (5,000–9,000 cm²). Among the polyp positions, lower values were observed mostly in center polyps in A. hyacinthus, while lower values were observed only in outer polyps in the other Acropora species. The distinct patterns between A. hyacinthus and the other two Acropora species suggest different reproductive strategies at the species level. Further studies are needed to confirm the prevalence of these effects in scleractinian corals, which will broaden our understanding of reproductive life history strategies and improve the estimation of reproductive performance.     

On the existence of two GABA pools associated with newly synthesized GABA and with newly taken up GABA in nerve terminals

[¹⁴C]Glutamic acid and [³H]GABA were injected into the lateral ventricle of mouse and then [¹⁴C]GABA and [³H]GABA in synaptosomes isolated from the animals were analysed. The [¹⁴C]GABA was interpreted to be newly synthesized GABA from [¹⁴C]glutamic acid while the [³H]GABA to be newly taken up GABA. We have obtained the following results: (1) when the animals were pretreated with aminooxyacetic acid and thus the GABA content in synaptosomes increased to about 2 times of the control level, only the [³H]GABA was enhanced to 3 times of the control level without any change of [¹⁴C]GABA, (2) the release of [¹⁴C]GABA from synaptosomes by high K⁺ depolarization was 1.5 times greater than that of [³H]GABA, (3) the releases of both [¹⁴C]GABA and [³H]GABA were increased in the presence of cold GABA,l-2,4-diaminobutyric acid or γ-amino-β-hydroxybutyric acid, but only slightly increased in the presence of β-alanine. These results would suggest that newly synthesized GABA and newly taken up GABA localized individually in different pools, which might localize either in different nerve terminals or separately in the same nerve terminal.     

Post-settlement survivorship in two Caribbean broadcasting corals

The post-settlement phase of broadcast-spawned coral life histories is poorly known due to its almost complete undetectability and, hence, presumed low abundance in the field. We used lab-cultured settled polyps of two important Caribbean reef-building species with negligible larval recruitment to quantify early post-settlement survivorship (6–9 weeks) over multiple years/cohorts and differing orientation on a reef in the Florida Keys. Orbicella faveolata showed significantly and consistently better survivorship in vertical rather than horizontal orientation, but no discernable growth overall. Meanwhile, Acropora palmata showed no significant difference in survivorship between orientations, but significantly greater growth in the horizontal orientation. Both species showed significant variation in mean survivorship between cohorts of different years; 0–47 % for O. faveolata and 12–49 % for A. palmata over the observed duration. These results demonstrate wide variation in success of cohorts and important differences in the larval recruitment capacities of these two important but imperiled reef-building species.     

EGFR-AKT-mTOR activation mediates epiregulin-induced pleiotropic functions in cultured osteoblasts

Epidermal growth factor (EGF) receptor (EGFR) emerges as an essential molecule for the regulating of osteoblast cellular functions. In the current study, we explored the effect of epiregulin, a new EGFR ligand, on osteoblast functions in vitro, and studied the underlying mechanisms. We found that epiregulin-induced EGFR activation in both primary osteoblasts and osteoblast-like MC3T3-E1 cells. Meanwhile, epiregulin activated AKT-mammalian target of rapamycin (mTOR) and Erk-mitogen-activated protein kinase (MAPK) signalings in cultured osteoblasts, which were blocked by EGFR inhibitor AG1478 or monoclonal antibody against EGFR (anti-EGFR). Further, in primary and MC3T3-E1 osteoblasts, epiregulin promoted cell proliferation and increased alkaline phosphatase activity, while inhibiting dexamethasone (Dex)-induced cell death. Such effects by epiregulin were largely inhibited by AG1478 or anti-EGFR. Notably, AKT-mTOR inhibitors, but not Erk inhibitors, alleviated epiregulin-induced above pleiotropic functions in osteoblasts. Meanwhile, siRNA depletion of Sin1, a key component of mTOR complex 2 (mTORC2), also suppressed epiregulin-exerted effects in MC3T3-E1 cells. Together, these results suggest that epiregulin-induced pleiotropic functions in cultured osteoblasts are mediated through EGFR-AKT-mTOR signalings.     

Expression of TNF-α, IFN-γ, TGF-β, and IL-4 in the Spinal Tuberculous Focus and Its Impact on the Disease

To investigate the expression of TNF-α, IFN-γ, TGF-β, and IL-4 in the spinal tuberculous focus and its relationship with the lesions type, severity, and bone destruction. The pathological samples of patients with spinal tuberculosis (TB) were divided into hyperplasia group and necrosis group according to their intra-operative and post-operative pathological findings. Normal bone tissues were taken as the control group. Pathology and expression of TNF-α, IFN-γ, TGF-β, and IL-4 in different tissues were compared among these three groups using immunohistochemical staining, quantitative image analysis, and measurement of bone tissue. 286 granulomas observed in the 14 samples in the hyperplasia group, which included 84 necrotizing and 202 non-necrotizing granulomas. As for the 20 samples in the necrosis group, there were 356 necrotizing and 186 non-necrotizing granulomas among all the 542 granulomas. The proportion of necrotizing granulomas in the necrosis group was significantly higher than that of the hyperplasia group. By inter-group comparison, expression of TNF-α, IFN-γ of granulomas in the hyperplasia group was significantly higher than that of the necrosis group, while the expression of TGF-β, IL-4 of granulomas in the necrosis group was significantly higher than that of the hyperplasia group. Also, expression of IFN-γ of non-necrotizing granulomas was significantly higher than that of necrotizing granulomas in the hyperplasia group, and expression of TGF-β in necrotizing granulomas was significantly higher than that of non-necrotizing granulomas in the necrosis group. The lesions were mainly bone resorption in the hyperplasia group, whereas mostly necrotic bones accompanied by local fibrosis in the necrosis group. Expression levels of TNF-α, IFN-γ in the hyperplasia group have a positive correlation to bone loss, whereas expression levels of TGF-β, IL-4 in the necrosis group have a positive correlation to the bone formation. The high expressions of TNF-α, IFN-γ in the spinal tuberculous focus were associated with protective immune cells. TGF-β and IL-4 were related to allergic lesions, fibrosis and osteogenesis. Expression imbalance of TNF-α, IFN-γ, TGF-β, and IL-4 might aggravate the allergy of TB.     

cDNA library construction from meristematic tissue of finger millet panicle

A protocol to obtain full-length cDNA using a SuperScript® Full-Length cDNA Library Construction Kit II (Invitrogen, United States) was developed, and a high quality cDNA library of meristem tissue of finger millet panicle (Eleusine coracana (L.) Gaertn) was constructed. The titer of the constructed cDNA library was 3.01 × 10⁵ CFU/mL, the average length of the insert was approximately 1070 base pairs, and the average efficiency of insertion of cDNA fragments was 99.5%. The sequencing of randomly selected clones created cDNA library was carried out. The cDNA sequences of clones were identified by BLAST search. The cDNA library analysis and selective sequencing indicate good functionality and full size of cDNA inserts of the clones. The constructed cDNA library from meristematic tissue of finger millet panicle is a good and reliable source for isolation and identification of key genes of metabolism and development of meristem as well for creation of new genetic markers for genetic research and molecular selection.     

The evolutionary pattern of aromatic amino acid biosynthesis and the emerging phylogeny of pseudomonad bacteria

Pseudomonad bacterial are a phylogenetically diverse assemblage of species named within contemporary genera that includePseudomonas, Xanthomonas andAlcaligenes. Thus far, five distinct rRNA homology groups (Groups I through V) have been established by oligonucleotide cataloging and by rRNA/DNA hybridization. A pattern of enzymic features of aromatic amino acid biosynthesis (enzymological patterning) is conserved at the level of rRNA homology, five distinct and unambiguous patterns therefore existing in correspondence with the rRNA homology groups. We sorted 87 pseudomonad strains into Groups (and Subgroups) by aromatic pathway patterning. The reliability of this methodology was tested in a blind study using coded cultures of diverse pseudomonad organisms provided by American Type Culture Collection. Fourteen of 14 correct assignments were made at the Group level (the level of rRNA homology), and 12 of 14 correct assignments were made at the finer-tuned Subgroup levels. Many strains of unknown rRNA-homology affiliation had been placed into tentative rRNA groupings based upon enzymological patterning. Positive confirmation of such strains as members of the predicted rRNA homology groups was demonstrated by DNA/rRNA hybridization in nearly every case. It seems clear that the combination of these molecular approaches will make it feasible to deduce the evolution of biochemical-pathway construction and regulation in parallel with the emerging phylogenies of microbes housing these pathways.     

Silica nanoparticles induce oxidative stress and inflammation of human peripheral blood mononuclear cells

In the present study, the effects of 10- or 100-nm silica oxide (SiO₂) NPs on human peripheral blood mononuclear cells (PBMC) were examined. Cytotoxic effects and oxidative stress effects, including glutathione (GSH) depletion, the formation of protein radical species, and pro-inflammatory cytokine responses, were measured. PBMC exposed to 10-nm NP concentrations from 50 to 4,000 ppm showed concentration-response increases in cell death; whereas, for 100-nm NPs, PBMC viability was not lost at <500 ppm. Interestingly, 10-nm NPs were more cytotoxic and induced more oxidative stress than 100-nm NPs. Immunoelectron micrographs show the cellular distribution of GSH and NPs. As expected based on the viability data, the 10-nm NPs disturbed cell morphology to a greater extent than did the 100-nm NPs. Antibody to the radical scavenger, 5,5-dimethyl-1-pyrroline N-oxide (DMPO), was used for Western blot analysis of proteins with radicals; more DMPO proteins were found after exposure to 10-nm NPs than 100-nm NPs. Examination of cytokines (TNF-α, IL-1ra, IL-6, IL-8, IL-1β, and IFN-γ) indicated that different ratios of cytokines were expressed and released after exposure to 10- and 100-nm NPs. IL-1β production was enhanced by 10- and 100-nm NPs;, the cytotoxicity of the NPs was associated with an increase in the IL-1β/IL-6 ratio and 100-nm NPs at concentrations that did not induce loss of cell viability enhanced IL-1β and IL-6 to an extent similar to phytohemagglutinin (PHA), a T cell mitogen. In conclusion, our results indicate that SiO₂ NPs trigger a cytokine inflammatory response and induce oxidative stress in vitro, and NPs of the same chemistry, but of different sizes, demonstrate differences in their intracellular distribution and immunomodulatory properties, especially with regard to IL-1β and IL-6 expression.     

Impregnation of the Bacterial Cellulose Membrane with Biologically Produced Silver Nanoparticles

Different wound dressings with antibacterial property have been surveyed and one among them is bacterial cellulose (BC). Since the BC does not have antibacterial property, the biologically produced silver nanoparticles (SNPs) were impregnated into the BC. For the BC production, Hestrin–Schramm broth was used. Formation of the BC was proven by enzymatic hydrolysis. For SNPs production, the bacterial supernatant was treated with AgNO₃ and formation of SNPs was monitored through spectrophotometer, TEM and XRD. For impregnation of SNPs into the BC, the cleaned membrane was placed in the bacterial supernatant that contained 1 mmol of AgNO₃. The antibacterial assay was done for the BC/SNPs. Enzymatic hydrolysis proved the presence of the BC. Spectrophotometer and XRD results showed the formation of SNPs. TEM analysis revealed the presence of SNPs with sizes around 5–100 nm. SEM micrographs showed the impregnation of SNPs into the BC. Antibacterial test exhibited the antibacterial activity of the BC/SNPs.