Investigative biological therapies for primary Sjögren's syndrome.

Primary Sjögren's syndrome (pSS) is a chronic, systemic autoimmune disease characterized by dryness of the eyes and mouth. The histological feature is mononuclear cell infiltration in exocrine glands, primarily salivary and lachrymal glands. As the disease progresses, some other tissues and organs may be involved and extraglandular manifestations ensue. The major current treatments are palliative and empirical, and in most cases the outcomes are not satisfactory. Emerging data indicate a critical role of lymphocytes in its development and progression. While pioneering work targeting B cells has demonstrated some encouraging results, more trials are warranted to validate the safety and efficacy. In addition, modulation of T cell function with abatacept ameliorates the severity of pSS. Furthermore, clinical trials to inhibit important cytokines involved in its formation have been carried out. In this article, we summarize and compare current biological therapies in order to find new and effective treatments for pSS.

Critical review on modified floating photocatalysts for emerging contaminants removal from landscape water: problems, methods and mechanism.

Due to the disorderly discharge in modern production and daily life of people, emerging contaminants(ECs) began to appear in landscape water, and have become a key public concern. Because of the unique characteristics of landscape water, it is difficult to efficiently remove ECs either by natural purification or by traditional large-scale sewage treatment facilities. The ideal purification method is to remove them while maintaining a beautiful environment. Possessing the feature of low-density, floating photocatalysts could harvest sufficient light on the surface of the water for photocatalytic degradation, which may be an important supplement for ECs treatment in landscape water. This paper gave a review related to floating photocatalysts and proposed an idea of combining floating photocatalysts to construct bionic photocatalytic materials for contaminative landscape water treatment. Six types of common floating substrates and corresponding applications for floating photocatalysts were concluded in this paper, and the main problem leading to the low efficiency of photocatalysts and three corresponding three improvement strategies were discussed. Besides, the modification mechanisms of photocatalysts were discussed thoroughly. On this basis, the engineering application prospects of bionic photocatalytic materials were proposed to remove ECs in landscape water.

Progress in semiconductor materials for photocathodic protection: Design strategies and applications in marine corrosion protection.

Metal protection of offshore equipment is very complicated owing to the complex marine environment. Photocathodic protection (PCP) is one of the popular research topics in marine metal protection. The protection efficiency of photoanode depends largely on the photoelectric properties of semiconductor materials, viz. the process of charge separation, charge migration, and light absorption. In this article, the enhancement strategies, photoelectrochemical properties, and electron transfer mechanisms of different composites for PCP were reviewed and highlighted. Some photoanodes with unusual and striking properties were emphasized. In addition, the outlooks and challenges of the application of PCP and the design of photoanodes materials are proposed.

Erythropoietin enhances meniscal regeneration and prevents osteoarthritis formation in mice.

Osteoarthritis (OA) is a leading cause of pain and disability, and knee is the most commonly afflicted joint. Meniscal tear due to injury or degeneration is an established factor for OA pathogenesis. Previous studies have demonstrated that meniscectomy does not reduce the OA incidence. We hypothesized that enhancing meniscal regeneration may prevent OA formation and progression. We first investigated the developmental pattern of mouse meniscus. Knee joint samples were collected at embryonic stages as well as after birth for histological and immunohistochemical studies. The results showed that meniscal cells underwent active proliferation and apoptosis at embryonic day 19.5 and Day 1 after birth. Collagen I (Col-1) is a major type of matrix protein in matured meniscus. Meniscal cells isolated from 3-month-old mice were used to examine the effect of selected factors on the molecules related to cell proliferation, angiogenesis, inflammation, extracellular matrix proteins and matrix degradation enzymes. Overall assessment indicated that EPO had optimal effect on meniscal regeneration. An organ culture system of mouse meniscus was established to test the effect of EPO on in vitro cultured menisci. EPO upregulated the expression of Col-1, Col-2 and VEGF-A, and downregulated the expression of MMP-13. Finally, we established a mouse model of meniscus injury induced OA (MIO), and mice were subjected to PBS or EPO treatments. The results demonstrated that EPO enhanced meniscal repair and prevented OA formation. EPO may become an effective Disease Modifying Osteoarthritis Drug and may be used for early treatment for meniscal injury to prevent OA progression.

Aggregation and Dissociation of Aqueous Al13 Induced by Fluoride Substitution.

The ε-Keggin ion AlO4Al12(OH)24(H2O)127+ (ε-K Al137+) is a double-edged sword, because it commonly acts as a toxic component toward aquatic organisms, but also is considered to be an effective coagulant. Gaining deep insight into the transformation of ε-K Al137+ in the presence of coexisting ligands would have significant implications for water environmental science, as well as for practical water purification. The aggregation and dissociation of aqueous Al137+ induced by fluoride (F-) substitution were herein investigated using nuclear magnetic resonance, electrospray ionization-mass spectrometry, and theoretical calculations. The F- substitution on η-OH2 sites was extremely fast, reducing the charge of ε-K Al137+ so that the repulsive force between fluorinated Al13 species was immediately reduced. Consequently, fluorinated Al13 aggregated, with the formula [Al13F5]2+, which was demonstrated by calculating the Gibbs free energy changes (ΔrG) of the substitution reactions involved. Moreover, the replacement of η-OH2 with F- weakened the strength of Al-OHa/b bonds and thus prompted the replacement of µ-OHa/b with F-. In addition, fluorination prompted [Al13F5]2+ to dissociate to oligomers.

Identification of Al13 on the Colloid Surface Using Surface-Enhanced Raman Spectroscopy.

Al13 is the most active polymeric Al species responsible for coagulation at the solid-liquid interface, whereas the detection techniques for Al13 at the interface are currently limited. In this study, for the first time, the identification of Al13 on the silicon dioxide-based colloid surface was realized by using surface-enhanced Raman scattering (SERS), which is an ideal surface method sensitive for single-molecule detection. The high purity Al13 salts were prepared by an electrolysis procedure followed by precipitation or metathesis. Al13-Cln was determined to be feasible for the Raman detection as it exhibited more noticeable signals in comparison to Al13-(SO4)p and Al13-(NO3)m. The peak of Al13-Cln at 635 cm-1 could be the major characteristic peak of Al13, and the other two peaks at 300 and 987 cm-1 could be accessorial evidence for the identification. Further, the identification of Al13 adsorbed on the surface of Ag and gold-core/silica-shell colloids was confirmed by the SERS response at the above three wavenumbers with a higher signal-to-noise ratio than the normal Raman scattering. According to the least-squares fitting computed Raman spectra, each of the characteristic peaks was associated with specific vibrational modes.

Rh(III)-Catalyzed Cascade Oxidative Annulation of Benzoylacetonitrile with Alkynes: Computational Study of Mechanism, Reactivity, and Regioselectivity.

The mechanism of the rhodium-catalyzed cascade oxidative annulation of benzoylacetonitrile with alkynes is investigated using density functional theory calculations. The result shows that the reaction undergoes a stepwise annulation process, wherein the 1-naphthol acts as an intermediate. The first-step annulation involves the sp(3) C-H bond cleavage, sp(2) C-H bond cleavage, alkyne insertion into the Rh-C(sp(2)) bond, ketone enolization, and reductive elimination to produce the 1-naphthol intermediate. The second-step annulation involves the O-H cleavage, sp(2) C-H bond cleavage, alkyne insertion into the Rh-C(sp(2)) bond, and C-O reductive elimination to generate the final product naphtho[1,8-bc]-pyran. The sp(3) C-H bond cleavage rather than the sp(2) C-H bond cleavage is found to be the rate-determining step of the catalytic cycle. The ketone enolization should occur before the reductive elimination. The substituent effects on the reactivities and regioselectivities of reactions are also analyzed. These calculation results shed light on some ambiguous suggestions from experiments.

Rhodium(I)-Catalyzed Benzannulation of Heteroaryl Propargylic Esters: Synthesis of Indoles and Related Heterocycles.

A de novo synthesis of a benzene ring allows for the preparation of a diverse range of heterocycles including indoles, benzofurans, benzothiophenes, carbazoles, and dibenzofurans from simple heteroaryl propargylic esters using a unified carbonylative benzannulation strategy. Multiple substituents can be easily introduced to the C4-C7 positions of indoles and related heterocycles.

Rigid Organization of Fluorescence-Active Ligands by Artificial Macrocyclic Receptor to Achieve the Thioflavin T-Amyloid Fibril Level Association.

The push-pull molecules with an intramolecular charge transfer from donor to acceptor sides upon excitation exhibit a wide variety of biological and electronic activities, as exemplified by the in vivo fluorescence imaging probes for amyloid fibrils in the diagnosis and treatment of amyloid diseases. Interestingly, the structurally much simpler bis(4,8-disulfonato-1,5-naphtho)-32-crown-8 (DNC), in keen contrast to the conventional macrocyclic receptors, was found to dramatically enhance the fluorescence of twisted intramolecular charge-transfer molecules possessing various benzothiazolium and stilbazolium fluorophores upon complexation. Spectroscopic and microcalorimetric titrations jointly demonstrated the complex structures and the interactions that promote the extremely strong complexation, revealing that the binding affinity in these artificial host-guest pairs could reach up to a nearly 10(7) M(-1) order of magnitude in water, and the sandwich-type complexation is driven by electrostatic, hydrophobic, π-stacking, and hydrogen-bonding interactions. Quantum chemical calculations on free molecules and their DNC-bound species in both the ground and excited states elucidated that the encapsulation by DNC could greatly deter the central single and double chemical bonds from free intramolecular rotation in the singlet excited state, thus leading to the unique and unprecedented fluorescence enhancement upon sandwich-type complexation. This complexation-induced structural reorganization mechanism may also apply to the binding of other small-molecule ligands by functional receptors and contribute to the molecular-level understanding of the receptor-ligand interactions in many biology-related systems.

Nickel-Catalyzed Hydroacylation of Styrenes with Simple Aldehydes: Reaction Development and Mechanistic Insights.

The first nickel-catalyzed intermolecular hydroacylation reaction of alkenes with simple aldehydes has been developed. This reaction offers a new approach to the selective preparation of branched ketones in high yields (up to 99%) and branched selectivities (up to 99:1). Experimental data provide evidence for reversible formation of acyl-nickel-alkyl intermediate, and DFT calculations show that the aldehyde C-H bond transfer to a coordinated alkene without oxidative addition is involved. The origin of the reactivity and regioselectivity of this reaction was also investigated computationally, which are consistent with experimental observations.

[IR spectral-analysis-based range estimation for an object with small temperature difference from background].

It is a typical passive ranging technology that estimation of distance of an object is based on transmission characteristic of infrared radiation, it is also a hotspot in electro-optic countermeasures. Because of avoiding transmitting energy in the detection, this ranging technology will significantly enhance the penetration capability and infrared conceal capability of the missiles or unmanned aerial vehicles. With the current situation in existing passive ranging system, for overcoming the shortage in ranging an oncoming target object with small temperature difference from background, an improved distance estimation scheme was proposed. This article begins with introducing the concept of signal transfer function, makes clear the working curve of current algorithm, and points out that the estimated distance is not unique due to inherent nonlinearity of the working curve. A new distance calculation algorithm was obtained through nonlinear correction technique. It is a ranging formula by using sensing information at 3-5 and 8-12 microm combined with background temperature and field meteorological conditions. The authors' study has shown that the ranging error could be mainly kept around the level of 10% under the condition of the target and background apparent temperature difference equal to +/- 5 K, and the error in estimating background temperature is no more than +/- 15 K.

catena-Poly[[[diaqua-copper(II)]-bis-[µ-1,5-bis-(1H-imidazol-1-yl)pentane-κ(2) N (3):N (3')]] naphthalene-1,5-disulfonate].

In the title complex, {[Cu(C11H16N4)2(H2O)2](C10H6O6S2)} n , the Cu(II) atom, lying on an inversion center, is six-coordinated by two water mol-ecules and four N atoms from four 1,5-bis-(1H-imidazol-1-yl)pentane (biim-5) ligands in a distorted octa-hedral geometry. Adjacent Cu(II) atoms are linked by two biim-5 ligands, forming a chain along [111]. Two atoms of the pentane group are disordered over two sets of sites, with an occupancy ratio of 0.554 (18):0.446 (18). Inter-molecular O-H⋯O hydrogen bonds link the chains and the centrosymmetric naphthalene-1,5-disulfonate anions into a layer structure parallel to (0-11).

Preparation and photocatalytic activity of eccentric Au-titania core-shell nanoparticles by block copolymer templates.

A novel route for a preparation of eccentric Au-titania core-shell nanoparticles using gold nanoparticles (AuNPs) with block copolymer shells as a template is reported. AuNPs with poly(2-vinyl pyridine)-block-poly(ethylene oxide) (PVP-b-PEO) block copolymer shells are first prepared by UV irradiation of the solution of PVP-b-PEO/HAuCl(4) complexes. Then the sol-gel reaction of titanium tetra-isopropoxide (TTIP) selectively on the surfaces of AuNPs leads to Au-titania core-shell composite nanoparticles. The eccentric Au-titania core-shell nanoparticles are obtained from the Au-titania core-shell composite nanoparticles by removal of organic interlayer by UV treatment. Photocatalytic activities of the resulting eccentric core-shell nanoparticles are investigated in terms of the degradation of methylene blue (MB). The results show that the eccentric core-shell structures endow the catalyst with greatly enhanced photocatalytic activity.