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BACKGROUND: When the jaw bone is subjected to an external force, the stress is transmitted from the force point along the alveolar bone to the skull and skull base. In the case of a dental implant, the stress distribution is mainly dependent on the implant position, type, and mechanical properties. OBJECTIVE: To investigate the dental implant position influence on the stress distribution and transmission in case of facial frontal trauma. Furthermore, the correlation between facial trauma and skull trauma in the case of a dental implant exists. METHODS: In this study, a Finite Element Method (FEM) model was constructed based on a real skull shape, size, and anatomy. Dental implants were modeled based on imported CAD Data. Five cases were investigated including no dental implant and the replacement of teeth no. 18, 19 20 and 21. Facial trauma was mimicked by applying an external load on the lower frontal jaw. Finally, the stress distribution based on the bone geometry and implant position were evaluated and compared. RESULTS: Results suggested that a dental implant could significantly influence the stress distribution in the skull in case of facial trauma. In addition, the dental position greatly affects stress transmission from the mandible to the skull bones through the zygomatic arch. CONCLUSION: The position of the dental implant could have a significant role in stress transmission and distribution in case of facial or even brain trauma. Thus, increasing the possibility of a correlation between facial and brain trauma.

The habitat occupied by flatfish fry differs considerably in light regime from that of the adult. The diversity of opsins and their expression patterns appear greatest for flatfishes to experience variable light environments. Yet, opsin repertoires and expression patterns in this group of fishes are poorly described. To understand how the visual system has adapted to such changes, we unveil that Japanese flounder (Paralichthys olivaceus) has a visual system adapted to a benthic environment by fine-tuning paralogous opsins (SWS2A and RH2) for wavelength shift and regulated expression. P. olivaceus express five basic opsin genes (M/LWS, SWS1, SWS2, RH1 and RH2) and gene-specific duplications were observed in RH2 and SWS2 paralogues. The expression of the three short-wavelength sensitive genes, SWS2Aα, SWS2Aβ, and SWS2B, is significantly elevated at the benthic stages, especially in SWS2Aβ a striking expression change is observed. The four middle-wavelength sensitive genes exhibit divergent expressions, the expression of RH2A-1 and RH2A-2 increased, while that of RH2B-1 and RH2B-2 decreased significantly from pelagic to benthic stage, especially RH2A-2. At present, changes at a total of 26 sites are known to have modified the λmax of various visual pigments during vertebrate evolution. Thus, these tuning site variations in our P. olivaceus are suspected to cause a green-shift in the λmax of SWS2Aα pigments and blue-shift in that of in RH2A-2. Together, our results suggest that RH2 and SWS2 opsin repertoires serve to optimize visual function under variable light environments by gene family duplications, differential expressions, and maximum absorption wavelength (λmax) variations.

In this study, fluorographene nanosheets (FG nanosheets) were prepared via the solvent-ultrasonic exfoliation method. The fluorographene sheets were observed using field-emission scanning electron microscopy (FE-SEM). The microstructure of the as-prepared FG nanosheets was characterized by X-ray diffraction (XRD) and a thermal analyzer (TG). The tribological properties of FG nanosheets as an additive in ionic liquids in high vacuum were compared to that of ionic liquid (IL) with graphene (IL-G). The wear surfaces and transfer films were analyzed via an optical microscope, Raman spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The results show that FG nanosheets can be obtained from the simple solvent-ultrasonic exfoliation method. The prepared G nanosheets are a sheet, and the longer the ultrasonic time is, the thinner the sheet is. Ionic liquids with FG nanosheets had low friction and a low wear rate under high vacuum conditions. The improved frictional properties were attributed to the transfer film of FG nanosheets and more formation film of Fe-F.

Fibroblast growth factors (FGFs) are short polypeptides that play essential roles in various cellular biological processes, including cell migration, proliferation, and differentiation, as well as tissue regeneration, immune response, and organogenesis. However, studies focusing on the characterization and function of FGF genes in teleost fishes are still limited. In this study, we identified and characterized expression patterns of 24 FGF genes in various tissues of embryonic and adult specimens of the black rockfish (Sebates schlegelii). Nine FGF genes were found to play essential roles in myoblast differentiation, as well as muscle development and recovery in juvelines of S. schlegelii. Moreover, sex-biased expression pattern of multiple FGF genes was recorded in the species’ gonads during its development. Among them, expression of the FGF1 gene was recorded in interstitial and sertoli cells of testes, promoting germ-cell proliferation and differentiation. In sum, the obtained results enabled systematic and functional characterization of FGF genes in S. schlegelii, laying a foundation for further studies on FGF genes in other large teleost fishes.

Fiber-reinforced polymers (FRPs) retrofit reinforced concrete (RC) structures. ABAQUS finite element software was used to perform numerical parametric analysis on a group of RC beams in this research. All specimens were retrofitted by FRP strips as an external retrofitting and experimentally tested up to previous researchers’ failure points. The range of subjects examined in these RC beams included cracking torque, ultimate torque, angle of twist, and the effect of using FRP on these subjects. We applied artificial neural networks (ANNs) to predict the structural behavior of RC beams under combined torsion and bending to develop the research accuracy. After testing, the ANN results were compared with the ABAQUS results. Consequently, a reasonable examination of the determined mathematical and trial results confirmed this study’s logical accuracy in predicting retrofitted RC beams’ structural behavior under combined loading.

In this paper, we investigated the effect of space irradiation on the lubricating properties of IL/(GO-MWCNT) solid–liquid lubricating coatings. The solid–liquid lubricating coatings consist of ionic liquids (IL), graphene oxide (GO), and multi-walled carbon nanotubes (MWCNT). Irradiation experiments were carried out using ground simulation equipment. Atomic oxygen (AO), ultraviolet (UV), proton (Pr), and electron (El) irradiation alter the composition, structure, morphology, and tribological properties of solid–liquid lubricating coatings. The experimental results show the composition changes induced by irradiation, including the decomposition of ILs lubricants. The damage to the lubricating material was the most serious by Pr irradiation and the least by UV irradiation.

Graphics processing units (GPUs) have become extremely important devices for accelerating computing performance in many applications. However, there have been few accurate models to estimate the performance of such applications running on modern GPUs. In this paper, we propose a performance model to estimate the execution times for massively parallel programs running on NVIDIA GPUs, one that takes on-chip resources and cost of data transfer between CPU and GPU into consideration. Four different GPUs with different architectures were used to evaluate our model. We demonstrated the effectiveness of the proposed model by applying it to various tasks in medical image registration. Experiments have demonstrated that by capturing on-chip GPU resources and data transfer time with our model, we were able to obtain a more accurate prediction of the actual running time, compared to the traditional model. Moreover, by using the optimal value of the block size parameter, estimated by our model, to accelerate the landmark tracking task on GPU devices, speedups of approximately 80×, 100×, 200× and 800×, on the C2050, K20c, M5000 and P100 can be achieved, making it possible to track massive numbers of landmarks and thereby improving the registration accuracy.

Quantifying regional myocardial motion and deformation from cardiac magnetic resonance imaging (MRI) plays an important role in clinical applications. In this paper, we present a novel approach for the estimation of left ventricle myocardial motion based on iterative deformable graph matching for cine MRI. Graph matching is a shape matching approach that can be used to determine the correspondence between two objects. However, existing graph matching algorithms are unsuitable for applications with large deformations. In this paper, we propose an iterative deformable graph matching framework for estimating the correspondence between points extracted from left ventricle myocardium at the end-diastolic and end-systolic phases to estimate cardiac motion. A new cost function for graph matching is defined to measure the discrepancy between the nodes and edges of two graphs under a transformation. By introducing a spatial transformation with a sparsity constraint, we can estimate a robust deformation field, alleviating the influence of inevitable graph mismatches. The correspondence between points is then updated by mapping the source graph using the estimated transformation. The cost function is optimized by alternatively optimizing for correspondence and spatial transformation. Furthermore, we propose a multilayer framework to improve correspondence accuracy using a bottom-up matching procedure. This framework estimates the deformation field between an image at the end-systolic phase and an image at the end-diastolic phase in an MRI sequence. Evaluations of two public cardiac datasets indicate that the proposed framework outperforms traditional graph matching algorithms in accuracy and robustness.

This paper studied the anti-seepage ability of the modified loess by using attapulgite, which is abundant in local areas. The possibility of using the modified loess as the sustainable compacted soil liner material in a solid waste landfill was also considered in this research. The materials were then evaluated using Nuclear Magnetic Resonance (NMR), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and an Impermeability Mechanism (IM). The experimental results showed that the permeability coefficient of the attapulgite-modified loess decreases significantly with increasing attapulgite content. However, it becomes less significant when the attapulgite level approaches 10%. Both cases can meet the landfill impermeability requirements, based on the attapulgite content remaining at 10%, adding 15% lime or 5% cement, respectively. The triaxial consolidation and drainage experiment was carried out to investigate the shear strength of the materials under three different working circumstances. The stress–strain curves of each specimen were produced, as were the cohesion and internal friction angle values. This research lays the groundwork for using attapulgite-modified loess as a landfill lining material. It establishes a solid platform for future studies on attapulgite adsorption and purifying performance in landfills.

This research study applied Artificial Neural Networks (ANNs) to predict and evaluate the structural responses of externally bonded FRP (EB-FRP)-strengthened RC T-beams under combined torsion and shear. Previous studies proved that, compared to reinforced concrete (RC) rectangular beams, RC T-beams performance in shear is significantly higher in structural analysis and design. The structural response of RC beams experiences a critical change while torsion moments are applied in load conditions. Fiber Reinforced Polymer (FRP) is used to retrofit the structural elements due to changing structural design codes and loadings, especially in earthquake-prone countries. We applied Finite Element Method (FEM) software, ABAQUS, to provide a precise numerical database of a set of experimentally tested FRP-retrofitted RC T-beams in previous research works. ANN predicted structural analysis results and Mean Square Error (MSE) and Multiple Determination Coefficients (R2) proved the accuracy of this study. The MSE values that were less than 0.0009 and R2 values greater than 0.9960 showed that the ANN precisely fits the data. The consistency between analyzed experimental and numerical results demonstrated the accurate implication of ANN, MSE, and R2 in predicting the structural responses of EB-FRP- strengthened RC T-beams.

The focus of this study was to investigate the effect of loess soil treated with lime on the lateral-seepage response. Three groups of box experiments were carried out to study the lateral-seepage effect under different types of loess-lime structures. Automated testing systems were designed to perform experiments and collect data. Additionally, numerical analysis of lateral-seepage impact and embankment settlement was performed. Finally, moisture content and settlement were monitored to quantify lateral-seepage effect results under corresponding loess-lime treatment. Results showed that loess-lime compaction piles and diaphragm wall structures could effectively prevent lateral seepage, and the latter was better. The simulated results are similar to the measured values of the box experiment, which indicates the accuracy of the simulation analysis and further supports the experimental results of this study.

A pair of 3-arylisoindolinone enantiomers: (+)-asperglactam A (1), (-)-asperglactam A (1) and a pair of nor-bisabolane enantiomers: (+)-1-hydroxyboivinianic acid (2), (-)-1-hydroxyboivinianic acid (2), along with seven known compounds (3-8) were obtained from the mangrove endophytic fungus Aspergillus versicolor SYSU-SKS025. Their structures were determined on the basis of HRESIMS and NMR spectroscopic data, and X-ray diffraction. (+)-Asperglactam A (1) and (-)-asperglactam A (1) are the first optically pure examples in the 3-arylisoindolinone family, which are rarely found in natural sources. All isolated compounds were evaluated for α-glucosidase inhibitory activity. The enantiomers of 1-3 showed moderate inhibitory activity against α-glucosidase with IC50 values ranging from 50 to 190μM. Compound 7 exhibited significant inhibitory activity against α-glucosidase with IC50 value of 7.5μM. In addition, compound 7 was found to inhibit nitric oxide production in RAW 264.7 macrophages with IC50 value of 12.5μM.

Two new compounds, named leptospyranonaphthazarin A ( 1 ) and leptosnaphthoic acid A ( 2 ), together with four known compounds ( 3–6 ) were isolated from an endophytic fungus Leptosphaerulina sp. SKS032. Their structures were assigned using spectroscopic methods, computational methods, and single-crystal X-ray diffraction analysis. In the antibiotic assay, compounds 1 , 2 , and 6 exhibited antibacterial activities against Staphylococcus aureus with minimal inhibitory concentration (MIC) values of 25.0, 50.0, and 50.0 μg/mL, respectively.

Seven new compounds: diaporchromanones A–D (1–4), (−)-phomopsichin A (5a), (+)-phomopsichin B (6a), and (±)-diaporchromone A (7), along with the known (+)-phomopsichin A (5b) and (−)-phomopsichin B (6b) were isolated from an endophytic fungus Diaporthe phaseolorum SKS019. The structures of the new compounds, including their absolute configurations, were determined on the basis of HRESIMS and NMR spectroscopic data, and experimental ECD and Rh2(OCOCF3)4-induced CD spectra analyses. Diaporchromanone A (1)/B (2), and C (3)/D (4) are two pairs of 3-epimers, and their structures possessing 3-substituted-chroman-4-one skeleton are rarely found in natural sources. (−)-Phomopsichin A (5a) and (+)-phomopsichin B (6a) are enantiomers of (+)-phomopsichin A (5b) and (−)-phomopsichin B (6b), respectively. All of the isolates were evaluated for their inhibitory effects against osteoclastogenesis in the RAW 264.7 cell line using luciferase reporter gene assays. Compounds 3–6b exhibited moderate inhibitory effects on osteoclastogenesis by suppressing the receptor activator of NF-κB by ligand-induced NF-κB activation.

Ocean acidification (OA), which is caused by increasing levels of dissolved CO2 in the ocean, is a major threat to marine ecosystems. Multiple lines of scientific evidence show that marine bivalves, including scallops, are vulnerable to OA due to their poor capacities to regulate extracellular ions and acid-based status. However, the physiological mechanisms of scallops responding to OA are not well understood. In this study, we evaluated the effects of 45 days of exposure to OA (pH 7.5) on the energy metabolism and antioxidant capability of Yesso scallops. Some biochemical markers related to energy metabolism (e.g., content of glycogen and ATP, activity of ATPase, lactate dehydrogenase, glutamate oxaloacetate transaminase, and glutamate-pyruvate transaminase), antioxidant capacity (e.g., reactive oxygen species level, activity of superoxide dismutase, and catalase) and cellular damage (e.g., lipid peroxidation level) were measured. Our results demonstrate that the effects of the reduced pH (7.5) on scallops are varied in different tissues. The energy reserves are mainly accumulated in the adductor muscle and hepatopancreas. Yesso scallops exhibit energy modulation by increasing lactate dehydrogenase activities to stimulate anaerobic metabolism. The highly active Na+/K+-ATPase and massive ATP consumption in the mantle and gill indicate that a large amount of energy was allocated for the ion regulation process to maintain the acid-base balance in the reduced-pH environment. Moreover, the increase in the reactive oxygen species level and the superoxide dismutase and catalase activities in the gill and adductor muscle, indicate that oxidative stress was induced after long-term exposure to the reduced-pH environment. Our findings indicate that the effects of OA are tissue-specific, and physiological homeostasis could be modulated through different mechanisms for Yesso scallops.

The innate immune system plays a pivotal role in defending invasion of microorganisms for scallops. Previous studies on immune-related genes in the Yesso scallop, Patinopecten yessoensis (Jay, 1857) have mainly focused on characterization and expression pattern in response to bacterial challenge, no research has been carried out on the cytogenetic level yet. In the present study, eight fosmid clones containing the sequences of key immune-related genes (PyNFkB, PyTRAF2, PyTRAF4, PyTRAF7, PyMyd88-1, PyMyd88-3, PyMKK-7 and PyTNFR) were isolated and seven of them were successfully mapped on chromosomes of Patinopecten yessoensis utilizing fluorescence in situ hybridization. Wherein, PyMyd88-1, PyMyd88-3 and PyMKK-7 located on the same chromosome pair with adjacent positions and the other genes were mapped on four non-homologous chromosome pairs, showing a similar distribution to another five model species. The isolation and mapping of such genes of the Yesso scallop will lay a foundation for studies such as assignment of interested genes to chromosomes, construction cytogenetic maps and so on.

Construction of cytogenetic maps can provide important information for chromosome identification, chromosome evolution and genomic research. However, it hasn't been conducted in many scallop species yet. In the present study, we attempted to map 12 fosmid clones containing tandem repeats by fluorescence in situ hybridization (FISH) in the Yesso scallop Patinopecten yessoensis (Jay, 1857). The results showed 6 fosmid clones were successfully mapped and distributed in 6 different pairs of chromosomes. Three clones were respectively assigned to a pair of metacentric chromosomes, a pair of submetacentric chromosomes and a pair of telocentric chromosomes and the remaining 3 clones showed their loci on three different pairs of subtelocentric chromosomes by co-hybridization. In summary, totally 8 pairs of chromosomes of the Yesso scallop were identified by 6 fosmid clones and two rDNA probes. Furthermore, 6 tandem repeats of 5 clones were sequenced and could be developed as chromosome specific markers for the Yesso scallop. The successful localization of fosmid clones will undoubtedly facilitate the integration of linkage groups with cytogenetic map and genomic research for the Yesso scallop.

A novel 3D metal–organic framework (MOF) {[Co 2.5 (dcpp) ( μ 3 -OH) ( μ -H 2 O)]·H 2 O} n (H 4 dcpp = 4,5-bis(4′-carboxylphenyl)-phthalic acid) with unprecedented ribbon-shaped secondary building units (SBUs), has been synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, and IR. In addition, the thermal stability and magnetic behavior of the complex were also investigated.

Arginine kinase (AK), an important member of the phosphokinase family, is involved in temporal and spatial adenosine triphosphate (ATP) buffering systems. AK plays an important role in physiological function and metabolic regulations, in particular tissues with high and fluctuating energy demands. In present study, four AK genes were firstly identified from Yesso scallop (Patinopecten yessoensis) genome, respectively named PyAK1-4. PyAKs have highly conserved structures with a six-exon/five-exon structure, except for PyAK3. PyAK3 contains an unusual two-domain structure and a "bridge intron" between the two domains, which may originate from gene duplication and subsequent fusion. Phylogenetic analysis showed that all PyAKs belonged to an AK supercluster together with other AK proteins from Mollusca, Platyhelminthes, Arthropoda, and Nematode. A transcriptome database demonstrated that PyAK3 and PyAK4 were the main functional executors with high expression level during larval development and in adult tissues, while PyAK1 and PyAK2 were expressed at a low level. Furthermore, both PyAK2 and PyAK3 showed notably high expression in the male gonad, and PyAK4 was broadly expressed in almost all tissues with the highest level in striated muscle, indicating a tissue-specific expression pattern of PyAKs. In addition, quantitative real-time PCR results demonstrated that the expression of PyAK2, PyAK3 and PyAK4 were significantly upregulated in response to pH stress, especially in an extremely acidifying condition (pH 6.5), revealing the possible involvement of PyAKs in energetic homeostasis during environmental changes. Collectively, a comprehensive analysis of PyAKs was conducted in P. yessoensis. The diversity of PyAKs and their specific expression patterns promote a better understanding of energy metabolism in the growth, development and environmental response of P. yessoensis.

Ocean acidification (OA), which is caused by increasing levels of dissolved CO2 in the ocean, is a major threat to marine ecosystems. Multiple lines of scientific evidence show that marine bivalves, including scallops, are vulnerable to OA due to their poor capacities to regulate extracellular ions and acid-based status. However, the physiological mechanisms of scallops responding to OA are not well understood. In this study, we evaluated the effects of 45 days of exposure to OA (pH 7.5) on the energy metabolism and antioxidant capability of Yesso scallops. Some biochemical markers related to energy metabolism (e.g., content of glycogen and ATP, activity of ATPase, lactate dehydrogenase, glutamate oxaloacetate transaminase, and glutamate-pyruvate transaminase), antioxidant capacity (e.g., reactive oxygen species level, activity of superoxide dismutase, and catalase) and cellular damage (e.g., lipid peroxidation level) were measured. Our results demonstrate that the effects of the reduced pH (7.5) on scallops are varied in different tissues. The energy reserves are mainly accumulated in the adductor muscle and hepatopancreas. Yesso scallops exhibit energy modulation by increasing lactate dehydrogenase activities to stimulate anaerobic metabolism. The highly active Na+/K+-ATPase and massive ATP consumption in the mantle and gill indicate that a large amount of energy was allocated for the ion regulation process to maintain the acid-base balance in the reduced-pH environment. Moreover, the increase in the reactive oxygen species level and the superoxide dismutase and catalase activities in the gill and adductor muscle, indicate that oxidative stress was induced after long-term exposure to the reduced-pH environment. Our findings indicate that the effects of OA are tissue-specific, and physiological homeostasis could be modulated through different mechanisms for Yesso scallops.

Midkine (Mdk) is a cytokine involved in controlling tissue repair and new tissue development, and regulating inflammation involved in several signaling pathway, such as the mitogen-activated protein kinase (MAPK) and phosphatidyl inositol 3-kinase (PI3K)/AKT pathways. But the role of Mdk in the development of Cynoglossus semilaevis is poorly understood. In this study, the Midkine of C. semilaevis (CsMdk) was cloned, and its spatiotemporal expression pattern and structural characteristics were analyzed. Furthermore, the essential genes related to nervous system development and germ layer formation marker gene were identified by qRT-PCR and in situ hybridization after overexpression the CsMdk via zebrafish model. The result showed CsMdk was mainly expressed in the brain of embryo, especially in the diencephalon, mid-hindbrain boundary (MHB) and hindbrain. In adult fish, it could only be detected in brain. Overexpression of CsMdk mRNA in zebrafish embryos suppressed the development of forebrain, midbrain, hindbrain and the notochord in zebrafish and influence the development of the mesoderm. All results showed CsMdk played a significant role on the germ layer and nervous development.

Toll-like receptors (TLRs) play a crucial role in innate immunity by recognizing specific pathogen-associated molecular patterns, including lipoproteins, lipopeptides, lipopolysaccharide, flagellin, dsRNA, ssRNA and CpG DNA motifs. Although significant effects of TLRs on immunity have been reported in most vertebrates and some invertebrates, the complete TLR superfamily has not been systematically characterized in scallops. In this study, 18 TLR genes were identified from Yesso scallop (Patinopecten yessoensis) using whole-genome scanning. Phylogenetic and protein structural analyses were performed to determine the identities and evolutionary relationships of the 18 genes. Extensive expansion of TLR genes from the Yesso scallop genome indicated gene duplication events. In addition, expression profiling of PyTLRs was performed at different acidifying exposure levels (pH = 6.50, 7.50) with different challenge durations (3, 6, 12 and 24 h) via in silico analysis using transcriptome and genome databases. Our results confirmed the inducible expression patterns of PyTLRs under acidifying exposure, and the responses to immune stress may have arisen through adaptive recruitment of tandem duplications of TLR genes. Collectively, this study provides novel insight into PyTLRs as well as the specific role and response of TLR signaling pathways in host immune responses against acidifying exposure in bivalves.

Endothelial dysfunction and hypertension is more common in individuals with diabetes than in the general population. This study was aimed to investigate the underlying mechanisms responsible for endothelial dysfunction of type 1 diabetic rats fed with high-salt diet.Type 1 diabetes (DM) was induced by intraperitoneal injection of streptozotocin (70 mg·kg(-1)). Normal or diabetic rats were randomly fed high-salt food (HS, 8% NaCl) or standard food (CON) for 6 weeks.Both HS (143±10 mmHg) and DM+HS (169±11 mmHg) groups displayed significantly higher systolic blood pressure than those in the CON group (112±12 mmHg, P0.01). DM+HS rats exhibited more pronounced impairment of vasorelaxation to acetylcholine and insulin compared with either DM or HS. Akt/endothelial nitric oxide synthase (eNOS) phosphorylation levels and nitric oxide (NO) concentration in DM+HS were significantly lower than in DM. The levels of caveolin-1 (cav-1) in DM+HS were significantly higher than that in DM and HS. Co-immunoprecipitation results showed increased interaction between cav-1 and eNOS in the DM+HS group. In the presence of cav-1 small interfering RNA (siRNA), eNOS phosphorylations in human umbilical vein endothelial cells (HUVEC) were significantly increased compared with control siRNA. Cav-1 was slightly but not significantly lower in HUVEC cultured with high glucose and high-salt buffer solution and pretreated with wortmannin or l-nitro-arginine methyl ester.Impaired endothelial Akt activation and increased cav-1 expression and resultant decreased eNOS activation contributes to aggravated high-salt diet-induced endothelial dysfunction and hypertension in DM rats.

The NikR protein is an essential DNA regulator of Helicobacter pylori, a human pathogen, which infects almost half of the world's population. Herein, we comprehensively characterized the interaction of a bismuth drug with Helicobacter pylori NikR. We show that Bi(III) can occupy the high-affinity Ni(II) site of NikR. The highly-conserved residue Cys107 at this site is critical for Bi(III) binding. Importantly, such a binding disassembles physiologically functional NikR tetramer into inactive dimer, leading to abrogation of the DNA-binding capability of NikR. Bi(III)-binding also significantly disturbs regulatory function of Helicobacter pylori NikR in vivo. Therefore, NikR might serve as a potential intracellular target of a bismuth drug.

Chromosome constitution was investigated in adult tetraploid Pacific oyster produced by blocking the first polar body of triploid eggs which were fertilized with haploid sperms. A high incidence of aneuploid and heteroploid mosaics were found among the offspring. Of 20 individuals identified, only 9 (45%) were eutetraploid which contained 40 chromosomes; 2 (10%) were aneuploid (hypotetraploid), which contained 39 and 38 chromosomes, respectively; and 9 (45%) were heteroploid mosaics. One mosaic was consisted of cells containing 40 and 39 chromosomes, respectiovely (1:1 in cell number), while the other 8 were consisted of cells containing chromosomes varying between tetraploid and triploid. It was also interesting to note that 3 mosaics even contained some diploid cells with 20 chromosomes. A certain number of cells of 2 tetraploids and 8 mosaics spread with 32–37 well-scattered and some clumped chromosomes at metaphase. The percentage of aneuploid cells with chromosomes varying between triploid and tetraploid correlated significantly with that of heteroploid mosaics cells with clumping chromosomes (P

Artificially induced tetraploid Pacific oyster, Crassostrea gigas Thunberg, produces more aneuploid gametes than normal diploid one, although they showed a comparable fecundity to diploidy. The meiotic chromosome configuration of 3 tetraploid and 1 tetraploid/triploid mosaic males were analyzed through direct chromosome observation. A majority of metaphase I spermatocytes contained both bivalents and quadrivalents. The chromosome configuration of these males was characterized by preferential formation of bivalents to quadrivalents. Bivalents appeared in all spermatocytes and consisted of 86% of all chromosome aggregates. In comparison, quadrivalents occurred in 91% spermatocytes and consisted of only 12.6% of all chromosome aggregates. The mean bivalent frequency per spermatocyte varied between 14.4 and 17.2; while that of quadrivalents varied between 2.2 and 2.7. Most quadrivalents were tandemly chained (58%) or circled (39%). The total number of chromosome aggregates per spermatocyte ranged from 13 to 20 with an average of 17.6; while 18 (16 bivalents and 2 quadrivalents) was the most frequent. Univalents and trivalents appeared in very low frequency. Aneuploid (hypotetraploid) spermatocytes were observed in a low frequency. The chromosome configuration of in the mosaic individual was similar to that of tetraploid individuals. The percentage of triploid spermatocytes (2%) of the mosaic individual was significantly lower (χ2 =30, P < 0.01) than that of triploid cells (46%) in its somatic tissue.

Four new polyketides: nectriacids A–C (1–3) and 12-epicitreoisocoumarinol (4), together with three known compounds: citreoisocoumarinol (5), citreoisocoumarin (6), and macrocarpon C (7) were isolated from the culture of the endophytic fungus Nectria sp. HN001, which was isolated from a fresh branch of the mangrove plant Sonneratia ovata collected from the South China Sea. Their structures were determined by the detailed analysis of NMR and mass spectroscopic data. The absolute configuration of the stereogenic carbons for compound 4 was further assigned by Mosher’s ester method. All of the isolated compounds were tested for their α-glucosidase inhibitory activity by UV absorbance at 405 nm, and new compounds 2 and 3 exhibited potent inhibitory activity with IC50 values of 23.5 and 42.3 μM, respectively, which were more potent than positive control (acarbose, IC50, 815.3 μM).

We demonstrate a bandgap-engineered dynamic monolithic MZI SOA all-optical switch with wide stripe selective area MOVPE. Compared with other simple laser-EAM integration with other bandgap engineering techniques, it is the largest working device ever achieved. All-optical wavelength conversion was achieved with single SOA all-optical modulation. In all-optical switching with differential phase technique, a 28 ps switching window was successfully demonstrated