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Osteomyelitis is an acute or chronic inflammatory bone disease with a high disability rate. As an anti-inflammatory factor, peroxisome proliferator activated receptor-γ (PPAR-γ) is not only implicated in a variety of inflammatory responses but also regulates osteoblast differentiation and bone mass. However, the role of PPAR-γ in osteomyelitis is not fully understood. In the present study, we demonstrated that PPAR-γ showed a lower expression level in infected bone tissue of osteomyelitis patients as compared with uninfected bone tissue from nonosteomyelitis patients with fracture of the hip. We applied lipopolysaccharides (LPSs) in MC3T3-E1 osteoblast precursor cell line as an in vitro model for osteomyelitis. LPS treatment increased osteomyelitis-associated inflammatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), whereas PPAR-γ levels and cell viability in MC3T3-E1 cells were suppressed. PPAR-γ antagonist GW9662 further enhanced IL-6 and TNF-α levels, and decreased cell viability in the presence of LPS treatment. In contrast, PPAR-γ agonist pioglitazone antagonized the effect of LPS treatment in MC3T3-E1 cells. These findings suggest that PPAR-γ downregulation is associated with the inflammation and progression of osteomyelitis, and PPAR-γ agonist could serve as a therapeutic strategy to attenuate inflammatory responses. This study provides novel insights into the physiopathogenesis of osteomyelitis and future study is required to validate the findings in animal model and uncover the molecular mechanism of PPAR-γ-dependent anti-inflammation in osteoblasts.

Background Thalassemia is one of the most common monogenic hemolytic disorders in the world. Hong Kongαα (HKαα) thalassemia was initially found among the people of southern China. Because of the complexity of genetic changes in HKαα thalassemia, we lack a precise sequence analysis of the HKαα allele. Here we aim to detect the specific genotype and trace the law of inheritance of this rare genotype. Methods We recruited an unprecedented huge pedigree containing 11 individuals carrying the HKαα thalassemia gene and 4 nongenetic‐related patients suffering from HKαα from south China. Regular hematological analysis and routine genetic screening were performed on the pedigree and two‐round nested PCR (polymerase chain reaction) for HKαα thalassemia were performed on each individual. The first‐generation gene sequencing was performed on six individuals, including four nongenetic‐related patients. Result We found that five family members were positive for the HKαα allele. Patients Ⅱ‐2, Ⅲ‐1, and Ⅱ‐3 with only HKαα/‐‐SEA or HKαα/‐α4.2 presented with α‐thalassemia minor trait. Ⅰ‐1, the carrier of both HKαα/‐α3.7 and β41‐42/βN, showed a typical β‐thalassemia trait. Fetus with genotype HKαα/‐α4.2 alone was not likely to suffer from any deleterious effects after birth. The whole sequence of HKαα allele revealed that HKαα alleles in the six patients shared a high similarity, implying that all HKαα alleles are likely from the same ancestor. Moreover, pedigree and sequencing analyses demonstrated that the HKαα allele contained αααanti4.2 mutation, ‐α3.7 mutation, and a fragment from α‐hemoglobin gene; thus, the composition and formation of HKαα allele was revealed. Finally, the high similarity and composition of HKαα alleles implies that once HKαα formed, αααanti4.2 and ‐α3.7 mutations tended to be a fusion gene and quite impossible to be inherited separately. Conclusion The two‐round nested PCR is an effective method to detect HKαα allele. Besides, our study for the first time revealed the sequence of the HKαα allele, the evidence of the same ancestor with HKαα thalassemia and enriched the composition as well as the formation mechanism of HKαα allele, and immediately opened up novel potential diagnosis and prenatal counseling for HKαα thalassemia., A rarely huge pedigree of HKαα thalassemia is reported and an effective prenatal counseling is offered to this family. Furthermore, αααanti4.2 detection assay is once again proposed to screen for HKαα allele in the patients positive for –α3.7mutation by our current studies. The relationship between genotypes and phenotypes of HKαα thalassemia was also analyzed here for clinicians to avoid the possible misdiagnosis. More importantly, our study for the first time reported the sequence of the HKααallele, the evidence of the same ancestor with HKαα thalassemia and enriched the composition as well as the formation mechanism of HKαα allele，and immediately opened up novel potential diagnosis and prenatal counseling for HKαα thalassemia.

Nuclear actin assembly in somatic cells has been an enigma for a long time. Recently, with the advancement of novel F-actin probes, researchers have started to uncover this mystery. In this study, we investigated the actin dynamics in somatic cell nuclei using two probes: Lifeact and Utr230. Surprisingly, we observed that both Lifeact and Utr230 significantly interfered with actin dynamics in cell nuclei. Moreover, these two probes induced distinct patterns of nuclear actin assembly. While Lifeact induced filamentous actin assembly in cell nuclei, Utr230 led to various patterns of actin aggregates, including fibers, small puncta, and large patches. Moreover, the interference of actin dynamics by Lifeact was limited to nuclear actin, while Utr230 induced actin aggregation in both the nucleus and cytoplasm. Using time-lapse microscopy, we found that Lifeact-induced actin fibers remained steady over hours of observation, indicating a deficiency of nuclear F-actin reorganization. These results suggest that Lifeact and Utr230 both interfere with nuclear actin dynamics but with distinct mechanisms. This is an important finding for research on nuclear actin assembly and highlights the potential value of these two probes for exploring the native mechanisms underlying nuclear actin dynamics, which appear to be altered in the presence of these probes.

Rapid and controllable formation of fluorescent carbon quantum dots (CQDs) is highly desirable in the fields of nanophotonics and biophotonics. Here, a novel strategy for creating CQDs, which emit white light efficiently under the excitation of either laser light or a mercury lamp, is proposed and demonstrated. The luminescent CQDs are generated by irradiating a poly(vinyl alcohol) (PVA) film doped with dense gold nanoparticles (AuNPs) with femtosecond laser pulses. The creation of CQDs from PVA is a two-step dehydration process mediated by AuNPs which act not only as heat sources but also as catalytic agents. The formation of CC, CC, and CO bonds is confirmed by infrared Fourier transformation spectroscopy and X-ray photoelectron spectroscopy. It is revealed both numerically and experimentally that a spatially localized temperature distribution at the deep subwavelength scale can be achieved in oligomers of AuNPs by resonantly exciting the Fano resonances formed in the oligomers of AuNPs, enabling the generation of CQDs with small diameters. As one of the potential applications, it is demonstrated that optical display and optical data storage with ultralow energy can be realized by selectively introducing luminescent CQDs in the AuNP/PVA film.

High symmetric porous Co3O4 hollow dodecahedra constructed by nanometer-sized building blocks are rationally synthesized by templating against Co-containing zeolitic imidazolate framework-67. The well-defined hollow structure and highly porous framework render these hollow dodecahedra exhibit high specific capacity, excellent cycling stability and superior rate capability when evaluated as an anode material for lithium-ion batteries.

On the basis of geological data and well log interpretation, the characteristics of the high-gamma-ray reservoirs for Yanchang Formation are analyzed. The results show that the high-gamma-ray reservoirs have the typical logging response characteristics, such as significant spontaneous potential (SP) negative anomalies, high gamma ray, high sonic wave slowness and low resistivity. And these reservoirs also have higher contents of feldspar, thorium (Th), uranium (U) and stable content of potassium (K). The characteristics of Th and U contents are similar to those of the tuffs. The development degree of the high-gamma-ray reservoirs increase from Chang 6 oil-bearing Member to Chang 4+5 oil-bearing Member, while that of tuffs becomes weaker in this order. The well log curve features of the higher gamma ray, higher acoustic transit time and lower resistivity of the high-gamma-ray reservoirs are similar to that of the tuffs. The three characteristics above indicate the sandstone might be produced by deposition of homochronous sedimentary volcano tuff ash or previous tuffs. The research results about the four-property relationships of the high-gamma-ray reservoirs show that: (1) high-gamma-ray reservoirs can be identified by the overlap of gamma ray and spontaneous potential curves and overlap of acoustic curve and spontaneous potential curves; (2) high-gamma-ray reservoirs have relatively well developed secondary pores with the strong heterogeneity, generally with better physical properties, the differences of amplitude between overlapped acoustic and spontaneous potential curves become greater; (3) the differential amplitude of overlapped calculated spontaneous potential curve and spontaneous potential curve can be used to evaluate the oil-bearing quality of reservoirs. Bigger amplitude differences of overlapped potential curves imply better oil-bearing property of the reservoirs.

have discovered that the legsof water striders have superhydrophobic coatings that bearhierarchical structures of many oriented tiny hairs with finenanogrooves. The superhydrophobic coatings were believedto be responsible for the water striders’ floating. However,since many other kinds of insects, such as mosquitoes, canfloat on the water surface with only normal hydrophobic coat-ings, it is not clear why superhydrophobic coatings are re-quired for the water strider’s legs. In the work reported here,using gold threads that are modified with normal hydrophobicor superhydrophobic coatings as model systems, we studied towhat extent the hydrophobicity contributes to the goldthread’s floating and movement on the water surface. In addi-tion, combining experimental results and theoretical forceanalysis, we report, for the first time, that deformation of thegold thread contributes to the total supporting force of thewater on the floating gold thread. For easily deformedfloatingobjects, such as very thin gold threads or legs of water striders,the contribution of deformation is significant compared to theother components of the supporting force. Our results suggestthat the superhydrophobiccoating of a water strider’s legs cannot only provide a larger supporting force, but also help to de-crease the insect’s total density beneath the water surface andallow it to move faster on the water surface. Therefore thesuperhydrophobic coating is indispensable, although the nor-mal hydrophobic coating provides enough supporting forcefor the water strider merely to float. We anticipate that ourresults provide a deeper understanding of the mechanism ofaquatic insects’ floating, and hope that it may lead to furtherresearch on drag-reducing materials and rapid underwatermotion.In an attempt to understand why a surperhydrophobic sur-face is needed by water striders, we modified gold threadswith superhydrophobic coatings (contact angle >150°) ornormally hydrophobic coatings (contact angle ≈110°).

The microstructure of electronically conducting polythiophene (Pth) films synthesized electrochemically was studied using a scanning electron microscope. A self-organization phenomenon was observed in the films, which grew on a substrate with periodically arrayed holes of diameter less than 100 nm. Owing to the low bending stiffness and the high cohesive energy of nanowires, they combined in a self-assembling manner into an interesting array of bundle shapes, each bundle having about 20-100 bonded nanowires. The physical mechanism of this phenomenon is elucidated using the theory of elastic buckling.

Conventional metamaterials are usually confined to planar settings due to the fabrication challenges at the nanoscale. Here, we explore the shape transformation of metasurfaces into three-dimensional metamaterials to generate some on-demand plasmon modes which would be otherwise unachievable in two dimensions. This method is inspired by the buckling-induced folding of a layer of metal sheet bonded to a stretchable compliant substrate in some specified regions. Two prototypes of three-dimensional metamaterials are obtained, demonstrating the enhancement of quality factors as well as the tunability. We find the occurrence of sharp Fano resonance and the resonance mode with toroidal dipole attributed to the structural asymmetry in depth. This work provides an effective approach to practical fabrication of nanoscale metamaterials in an extra dimension that would enable a wide range of applications in the optical spectrum.

Pre-treatment of citrus leaves and leaf explants (Citrus sinensis [L.] Osbeck cv. Shamouti), with 1-methylcyclopropene (1-MCP), induced endogenous ethylene production when leaves were further incubated in air. The induction of ethylene production was 1-MCP concentration-dependent. Abscission was concomitantly delayed. In leaves pre-treated with 1-MCP followed by exposure to ethylene, abscission was significantly delayed in comparison with those without 1-MCP pre-treatment. When leaf explants were co-treated for 24 h with ethylene and 1-MCP, abscission was delayed quite efficiently. The Lineweaver-Burke plot yielded a half-maximal value of 0.234 μl l -1 for the effect of ethylene on abscission. 1-MCP -1 competed kinetically with ethylene with a K i value of approximately 1.4-5.5 nl l -1 1-MCP. Under these experimental conditions there was some competition between 1-MCP and ethylene. However, ethylene was not able to completely counteract the inhibitory effect of 1-MCP. Pre-treatment with 1-MCP, followed by exogenous ethylene treatment, suppressed the induction of endo-β-glucanase (EG) activity at the laminar abscission zone. The ethylene-dependent accumulation of the hydrolyse gene was demonstrated by blocking the accumulation of CsCel al mRNA by 1-MCP. Six hours of exposure of leaves to 1-MCP at various times during a total of 24 h ethylene treatment efficiently reversed ethylene induction of CsCel al gene at mRNA level up to 18 h. The results demonstrate that the induction of abscission by ethylene is controlled at mRNA level at the abscission zone.

A cohesive damage zone model is presented for a circular crack in a quasi-brittle material. Analytical expressions are derived for the size of the coheswe zone, the opening displacement under loading and the residual displacement after unloading.

Lead-free (Na0.5Bi0.5)0.94TiO3–Ba0.06TiO3 (NBT-BT6) nanofibers were synthesized by the sol–gel process and electrospinning, and a butterfly-shaped piezoelectric response was measured by scanning force microscopy. NBT-BT6 nanofibers with perovskite phase were formed, after being cleaned at 700 °C for 1 hour, and the diameters are in the range of 150 nm to 300 nm. The average value of the effective piezoelectric coefficient d33 is 102 pm/V. The high piezoelectricity may be attributed to the easiness for the electric field to tilt the polar vector of the domain and to the increase of the possible spontaneous polarization direction. There is a potential for the application of NBT-BT6 nanofibers in nanoscale piezoelectric devices. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Flexible and stretchable optoelectronics, built-in inorganic semiconductor materials, offer a wide range of unprecedented opportunities and will redefine the conventional rigid optoelectronics in biological application and medical measurement. However, a significant bottleneck lies in the brittleness nature of rigid semiconductor materials and the performance's extreme sensitivity to the light intensity variation due to human skin deformation while measuring physical parameters. In this study, the authors demonstrate a systematic strategy to design an epidermal inorganic optoelectronic device by using specific strain-isolation design, nanodiamond thinning, and hybrid transfer printing. The authors propose all-in-one suspension structure to achieve the stretchability and conformability for surrounding environment, and they propose a two-step transfer printing method for hybrid integrating III-V group emitting elements, Si-based photodetector, and interconnects. Owing to the excellent flexibility and stretchability, such device is totally conformal to skin and keeps the constant light transmission between emitting element and photodetector as well as the signal stability due to skin deformation. This method opens a route for traditional inorganic optoelectronics to achieve flexibility and stretchability and improve the performance of optoelectronics for biomedical application.

A range of new cinchona alkaloid ester derivatives having a phthaloyl or pyridyl spacer group are synthesized and successfully applied as chiral ligands in the title asymmetric hydroxylation reactions.

The efficient synthesis of N -(diphenylmethylene) glycine alkyl esters was achieved for the first microwave irradiation under solvent-free condition, using PEG or quaternary ammonium salts as phase transfer catalysts (PTCs). Under the optimum conditions, N -(diphenylmethylene) glycine alkyl esters were obtained in excellent yields in most cases.

A free bis-cinchona alkaloid derivative ligand was prepared by a simple synthetic manipulation. With ligand/olefin mole ratio of 1%, the asymmetric dihydroxylation reactions of six olefins proceeded smoothly to give the chiral vicinal diols in high chemical yields and optical yields. The ligand itself could be recovered quantitatively by a simple operation and reused five times without loss of enantioselectivity.

Gold threads modified with superhydrophobic or normal hydrophobic coatings are used as model system in the study of the contribution of a superhydrophobic coating of water striders to their floating and movement on water surfaces. After depositing Pt aggregates on one of its ends, the gold threads are able to move in the H2O2 aqueous solution. The superhydrophobic coating is proven to be able to decrease fluidic drag during motion, as described by Xi Zhang and co-workers on p. 2257.