MOF-Derived Fe7 S8 Nanoparticles/N-Doped Carbon Nanofibers as an Ultra-Stable Anode for Sodium-Ion Batteries.

Sodium-ion batteries (SIBs) have aroused wide concern due to their potential applications in large-scale energy-storage systems. In this work, a hybrid of Fe7 S8 nanoparticles/N-doped carbon nanofibers (Fe7 S8 /N-CNFs) is designed and synthesized via electrospinning. As an anode for SIBs, Fe7 S8 /N-CNFs exhibit a high reversible capacity of 649.9 mAh g-1 at 0.2 A g-1 after 100 cycles, and superior cycling stability for 2000 cycles at 1 A g-1 with only 0.00302% capacity decay per cycle. Such excellent performance originates from: i) Fe7 S8 nanoparticles (average diameter of 17 nm), which shorten the Na+ diffusion distance; ii) the unique 3D N-CNFs, which enhance the conductivity, alleviate the self-agglomeration and large volume change of Fe7 S8 nanoparticles, and offer numerous active sites for Na+ adsorption and paths for electrolyte diffusion. The fascinating structure and superior electrochemical properties of Fe7 S8 /N-CNFs shed light on developing high-performance SIBs anode materials.

Conductive Hydrogel for a Photothermal-Responsive Stretchable Artificial Nerve and Coalescing with a Damaged Peripheral Nerve.

Modern development of flexible electronics has made use of bioelectronic materials as artificial tissue in vivo. As hydrogels are more similar to nerve tissue, functional hydrogels have become a promising candidate for bioelectronics. Meanwhile, interfacing functional hydrogels and living tissues is at the forefront of bioelectronics. The peripheral nerve injury often leads to paralysis, chronic pain, neurologic disorders, and even disability, because it has affected the bioelectrical signal transmission between the brain and the rest of body. Here, a kind of light-stimuli-responsive and stretchable conducting polymer hydrogel (CPH) is developed to explore artificial nerve. The conductivity of CPH can be enhanced when illuminated by near-infrared light, which can promote the conduction of the bioelectrical signal. When CPH is mechanically elongated, it still has high durability of conductivity and, thus, can accommodate unexpected strain of nerve tissues in motion. Thereby, CPH can better serve as an implant of the serious peripheral nerve injury in vivo, especially in the case that the length of the missing nerve exceeds 10 mm.

[Manual Acupuncture Stimulation Regulates Expression of Receptor Activity-modifying Protein 1 and 5-HT 1 D Receptor Proteins and Genes in Migraine Rats].

OBJECTIVE: To observe the effect of liver-soothing and mental-activity-regulating (LSMAR) needling on the expression of receptor activity-modifying protein 1 (RAMP 1, receptor of calcitonin gene-related peptide), 5-hydroxytryptamine 1 D receptor(5-HT 1 DR) in the spinal trigeminal nucleus (STN) and midbrain in migraine rats, so as to explore its underlying mechanism in relieving migraine. METHODS: A total of 40 male Wistar rats were randomly divided into control, model, LSMAR and conventional needling groups (n=10 rats in each). The migraine model was established by subcutaneous injection of nitroglycerin at the posterior neck. LSMAR was applied to "Baihui" (GV 20), bilateral "Fengchi" (GB 20), "Neiguan" (PC 6) and "Taichong" (LR 3) in the LSMAR group and conventional needling was applied to "Baihui" (GV 20) and bilateral "Fengchi" (GB 20) in the conventional acupuncture group for 30 min, once a day for 8 days before modeling. The expression levels of RAMP 1 and 5-HT 1 DR proteins and mRNAs in the STN and mesencephalon were detected by real-time fluorescent quantitative PCR and Western blot, separately. RESULTS: Compared with the control group, the expression levels of RAMP 1 protein and mRNA in STN and mesencephalon were significantly increased (P<0.05) and those of 5-HT 1 DR protein and mRNA considerably decreased (P<0.05) in the model group. After the acupuncture treatment, the increased levels of RAMP 1 protein and mRNA and the decreased levels of 5-HT 1 DR protein and mRNA in the STN and midbrain were obviously reversed in the LSMAR and conventional needling groups relevant to the model group (P<0.05). The effect of LSMAR needling was significantly superior to that of conventional needling in down-regulating the expression levels of RAMP 1 mRNA and protein in the STN and mesencephalon (P<0.05) and in up-regulating the expression levels of 5-HT 1 DR mRNA and protein in the two brain regions (P<0.05). CONCLUSION: Manual acupuncture stimulation of GV 20, GB 20, etc. can inhibit the expression of RAMP 1 protein and mRNA in the STN and midbrain, and up-regulate the expression of 5-HT 1 DR in the two brain regions of migraine rats, which may be related to its effect in relieving migraine.

[Effect of Manual Acupuncture Preconditioning on Behavior and Contents of Serum CGRP, SP, IL-1 ß and TNF-α Levels in Migraine Rats].

OBJECTIVE: To observe the effect of liver-soothing and mental-activity-regulating (LSMAR) needling on behavior reactions and contents of serum calcitonin gene-related peptide (CGRP), substance P (SP), interleukin-1 ß (IL-1 ß) and tumor necrosis factor-α (TNF-α) in migraine rats, so as to explore its mechanism underlying relief of migraine. METHODS: Thirty-two male Wistar rats were randomly divided into control, model, LSMAR needling and conventional needling groups (n=8 rats in each). The migraine model was established by hypodermic injection of glyceryl trinitrate (5 mg/kg) at the napex. Acupuncture preconditioning was conducted once daily for 8 days before modeling. Acupuncture needles were inserted into "Baihui" (GV 20), and bilateral "Fengchi" (GB 20), "Neiguan" (PC 6) and "Taichong" (LR 3), manipulated for a while and retained for 30 min. The rats' behavioral changes (times of head scratching, tail-biting, cage-crawling, and to- and fro-movement in 30 min) were scored (one symptom = one point) before modeling, after modeling, and after intervention. The concentrations of CGRP, SP, IL-1 ß, TNF-α in serum were assayed by enzyme-linked immunosorbent assay (ELISA). RESULTS: After modeling, the behavioral scores were significantly increased in the migraine model rats relevant to the control group (P<0.05). Whereas after the treatment, the behavior scores were considerably decreased during 60-90 min and 120-150 min of the measuring period in both LSMAR and conventional needling groups compared with the model group (P<0.05). The concentrations of CGRP, SP, IL-1 ß and TNF-α were significantly higher in the model group than in the control group (P<0.05), and notably lower in both LSMAR and conventional needling groups than in the model group (P<0.05). The therapeutic effect of LSMAR was markedly superior to that of conventional needling in down-regulating the concentrations of CGRP, SP, IL-1 ß and TNF-α (P<0.05). CONCLUSION: Acupuncture preconditioning can effectively relieve pain in migraine rats possibly by decreasing the concentrations of CGRP, SP, IL-1 ß and TNF-α in the peripheral blood, and the therapeutic effect of LSMAR is evidently superior to that of conventional needling.

Biodegradable Smart Nanogels: A New Platform for Targeting Drug Delivery and Biomedical Diagnostics.

Nanogels (or nanohydrogels) have been extensively investigated as one of the most promising nanoparticulate biomedical platforms owing to their advantageous properties that combine the characteristics of hydrogel systems with nanoparticles. Among them, smart nanogels that have the ability to respond to external stimuli, such as pH, redox, temperature, enzymes, light, magnetic field and so forth, are most attractive in the area of drug delivery. Besides, numerous multifunctionalized nanogels with high sensitivity and specificity were designed for diagnostic applications. In this feature article, we have reviewed and discussed the recent progress of biodegradable nanogels as smart nanocarriers of anticancer drugs and biomedical diagnostic agents for cancer.

Magnetic MSP@ZrO2 microspheres with yolk-shell structure: designed synthesis and application in highly selective enrichment of phosphopeptides.

Magnetic yolk-shell MSP@ZrO2 microspheres consisting of a movable magnetic supraparticle (MSP) core and a crystalline ZrO2 shell were synthesized via a two-step controlled "sol-gel" approach for the first time. First, a large amount of the generated hydrolyzate Zr(OH)4 was firmly fixed onto the surface of the cross-linked polymethylacrylic acid matrix via a strong hydrogen-bonding interaction between Zr(OH)4 and the carboxyl groups. Then a calcination process was adopted to convert the Zr(OH)4 into a continuous ZrO2 shell and simultaneously make the ZrO2 shell crystallized. At the same time, the polymer matrix could be selectively removed to form a yolk-shell structure, which has better dispersibility and higher adsorbing efficiency of phosphopeptides than its solid counterpart. The formation mechanism of such yolk-shell microspheres could be reasonably proved by the results of TEM, TGA, VSM, XRD, and FT-IR characterization. By taking advantage of the unique properties, the yolk-shell MSP@ZrO2 exhibited high specificity and great capability in selective enrichment of phosphopeptides, and a total of 33 unique phosphopeptides mapped to 33 different phosphoproteins had been identified from 1 mL of human saliva. This result clearly demonstrated that the yolk-shell MSP@ZrO2 has great performance in purifying and identifying the low-abundant phosphopeptides from real complex biological samples. Moreover, the synthetic method can be used to produce hybrid yolk-shell MSP@ZrO2-TiO2.

Cancer therapy and fluorescence imaging using the active release of doxorubicin from MSPs/Ni-LDH folate targeting nanoparticles.

Hierarchical structured nanomaterials with diverse functionality, such as magnetic susceptibility, stimuli-responsiveness, environmental sensing and biocompatibility, are highly sought after for biomedicine and biodetection alike. In this study, we designed and fabricated a new kind of multifunctional core/shell nanospheres as biodegradable targeted drug carriers, the controlled drug release progress and therapeutic effect were monitored in-situ by the fluorescent state of the cells. Firstly, the core/shell nanospheres with biodegradability were synthesized using magnetic supraparticles (MSPs) as core and the layered double hydroxide (LDH) as shell via a hydrothermal route, the reaction parameters were well investigated to obtain the desired structure of the LDH shell. The anti-cancer drug doxorubicin was modified with carboxyl group (DOX-COOH) and loaded in the shell of MSPs/LDH nanospheres via an anion-exchange intercalation. To endow the nanospheres with tumor-targeting capability, IDA (iminodiacetic acid)-modified folate was successfully immobilized onto the surface of LDH shell using chelating interaction. These nanospheres behaved as multifunctional carriers for targeted delivery of anti-cancer drug, doxorubicin (DOX), within Hela cells and thus, these nano-drugs exhibited clear cytotoxicity and inhibition toward Hela cells as compared to normal cell-lines of HEK 293T cells. Interestingly, after the internalization of these nano-drugs, there was a sharp contrast in illumination between the tumorous Hela cells and the normal HEK 293T cells, the acidic cytoplasm of Hela cell stimulated DOX-COOH in LDH shell quickly degraded into positive-charged DOX, and then rapidly escaped from the positive-charged intercalation of LDH shell by strong repulsive interaction, the released DOX rapidly lit up the whole tumor cells in a short time, but only very weak light was found in HEK 293T cells.

RACK1 (receptor for activated C-kinase 1) interacts with FBW2 (F-box and WD-repeat domain-containing 2) to up-regulate GCM1 (glial cell missing 1) stability and placental cell migration and invasion.

GCM1 (glial cell missing 1) is a short-lived transcription factor essential for placental development. The F-box protein, FBW2 (F-box and WD-repeat domain-containing 2), which contains five WD (tryptophan-aspartate) repeats, recognizes GCM1 and mediates its ubiquitination via the SCFFBW2 E3 ligase complex. Although the interaction between GCM1 and FBW2 is facilitated by GCM1 phosphorylation, it is possible that this interaction might be regulated by additional cellular factors. In the present study, we perform tandem-affinity purification coupled with MS analysis identifying RACK1 (receptor for activated C-kinase 1) as an FBW2-interacting protein. RACK1 is a multifaceted scaffold protein containing seven WD repeats. We demonstrate that the WD repeats in both RACK1 and FBW2 are required for the interaction of RACK1 and FBW2. Furthermore, RACK1 competes with GCM1 for FBW2 and thereby prevents GCM1 ubiquitination, which is also supported by the observation that GCM1 is destabilized in RACK1-knockdown BeWo placental cells. Importantly, RACK1 knockdown leads to decreased expression of the GCM1 target gene HTRA4 (high-temperature requirement protein A4), which encodes a serine protease crucial for cell migration and invasion. As a result, migration and invasion activities are down-regulated in RACK1-knockdown BeWo cells. The present study reveals a novel function for RACK1 to regulate GCM1 activity and placental cell migration and invasion.

Highly sensitive detection of target ssDNA based on SERS liquid chip using suspended magnetic nanospheres as capturing substrates.

A new approach for sensitive detection of a specific ssDNA (single-stranded DNA) sequence based on the surface enhanced Raman spectroscopy (SERS) liquid chip is demonstrated. In this method, the probe DNA (targeting to one part of target ssDNA) was attached to the nano-SERS-tags (poly(styrene-co-acrylic acid)/(silver nanoparticles)/silica composite nanospheres), and the capture DNA (targeting to the other part of target ssDNA) was attached to the Fe3O4/poly(acrylic acid) core/shell nanospheres. The nano-SERS-tags with probe DNA were first allowed to undergo hybridization with the target ssDNA in solution to achieve the best efficiency. Subsequently, the magnetic composite nanospheres with capture DNA were added as the capturing substrates of the target ssDNA combined with the nano-SERS-tags. Upon attraction with an external magnet, the nanospheres (including the nano-SERS-tags) were deposited together due to the hybridization, and the deposit sediment was then analyzed by SERS. Quantitative detection of target ssDNA was achieved based on the well-defined linear correlation between the SERS signal intensity and the target ssDNA quantity in the range of 10 nM to 10 pM, and the limit of detection was approximately 10 pM. Multiplexed detection of up to three different ssDNA targets in one sample was demonstrated using three different types of nano-SERS-tags under a single excitation laser. The experimental results indicated that the liquid-phase DNA sequencing method, thus named the SERS liquid chip (SLC) method, holds significant promises for specific detection of trace targets of organisms.

Synthesis of mesoporous magnetic Co-NPs/carbon nanocomposites and their adsorption property for methyl orange from aqueous solution.

Mesoporous magnetic Co-NPs(nanoparticles)/carbon nanocomposites were synthesized by carbonization of polyacrylonitrile (PAN) microspheres entrapped with cobalt salt for the first time. The structure and morphology of the porous magnetic nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), and N(2) adsorption-desorption technique. The nanocomposites possess very high saturation magnetization (Ms is up to ~133 emu/g), near-zero remanence, and very low coercivity (Hc is down to ~0.023 KOe). Meanwhile, the nanocomposites have mesoporous structure with average pore size of 4 nm and high specific surface area of 232 m(2)/g, which can be tuned by changing the carbonization conditions. Using methyl orange (MO) as model pollutant in water, the mesoporous magnetic nanocomposites showed good adsorption capacity of 380 mg/g, and the absorbed MO could be easily released in ethanol. The mesoporous nanocomposites were facile separated from solution under external magnetic force, and over 85% adsorption capacity for MO could be retained after five adsorption/desorption cycles.

[Spatial distribution characteristics and correlation analysis of organic matter, total nitrogen and total phosphorus in topsoil around Chaohu Lake].

Sixty topsoil composite samples (0-20 cm) have been collected in 3 258 km2 surrounding area of Chaohu Lake. The concentrations of organic material (OM), total nitrogen (TN) and total phosphorus (TP) were determined, and their spatial distribution characteristics were studied by geo-statistics software named GS 7.0 +, Surfer 8.0 and Mapinfo 8.5. The correlations of these 3 kinds of nutrient were analyzed by SPSS 17.0 at the same time. Results showed that the average omega (OM), omega (TN) and omega (TP) in topsoil around Chaohu Lake were 19 500 mg x kg(-1), 1 027 mg x kg(-1) and 483 mg x kg(-1). The omega (OM) and omega (TN) in topsoil in the east of Chaohu Lake were both higher than those in the west of the lake, while omega (TP) was reverse. The omega (TP) in topsoil around Hangbu-Fengle River and Baishitianhe River which located in the southwest of Chaohu Lake was higher than that in any other rivers and with the serious soil erosion. Hence, to control the TP released by nonpoint pollution, attention should be paid on these two rivers. Furthermore, the semivariogram models of omega (OM), omega (TN) and omega (TP) followed linear model and they all had a strong spatial autocorrelation, the ratios of nugget to sill were 0.015, 0.202 and 0.128, respectively. The characteristics of spatial distribution of omega (OM), omega (TN) and omega (TP) were similar. Moreover, the Pearson correlation analysis showed that omega (OM), omega (TN) and omega (TP) were significantly correlated. The omega (TN) and omega (TP) can be calculated by two recommended formulas, and the results were acceptable in daily non-pint pollution management.

[Discussion on the control of treatment amount of acupuncture and moxibustion for peripheral facial paralysis].

To explore the control principles of treatment amount of acupuncture and moxibustion for peripheral facial paralysis. (1) Early stage: in this period, the selected acupoints should be few, therapy should be easy and simple, and the treatment amount should be small and basically constant, which is called constant acupoints and amount. (2) Middle stage: the treatment of this stage should be given with more acupoints and various therapies, the treatment amount should be gradually increasing and reach the peak within a certain time and keep it for an appropriate time, which is called increasing acuponts and amount. (3) Late stage: the treatment at this stage should be given with more acupoints, lesser therapies, and the treatment amount should be gradually decreasding and get the valley point within a certain time, which is called more acupoints and less amount. (4) Sequelae stage: the selection of acupoints at this stage should be focus on areas which there are the obvious symptoms, and solo type of therapy and little treatment amount is required, which is called changing acupoints and little amount. In a word, the best therapeutic effect could be achieved on condition that the control principles of treatment amount for peripheral facial paralysis are followed during the clinical practice.

[DNA methylation status of RARß2 and p16(INK4α) in peripheral blood and tumor tissue in patients with esophageal squamous cell carcinoma].

OBJECTIVE: To study the methylation status of retinoic acid receptor ß2 (RARß2) and p16(INK4α) genes in peripheral blood and tumor tissues and the perioperative dynamic changes of free RARß2 and p16(INK4α) in the peripheral blood, and to investigate the relationship between RARß2 and p16(INK4α) methylation in peripheral blood and clinicopathological characteristics of esophageal squamous cell carcinoma (ESCC) and their value in evaluating the completeness of surgical resection. METHODS: Real-time methylation specific polymerase chain reaction (real-time MSP) technique was used to detect the methylation status of RARß2 and p16(INK4α) in tumor tissue, adjacent normal tissue and peripheral blood perioperatively in 76 cases of ESCC. Sixty age-matched healthy volunteers were randomly selected as a control. RESULTS: RARß2 and p16(INK4α) hypermethylation presented in both tumor tissue [72.4% (55/76) and 86.8% (66/76)] and peripheral blood [63.2% (48/76) and 71.1% (54/76)] in the ESCC patients, showing a good agreement between them. RARß2 and p16(INK4α) hypermethylation was significantly related with pathological stage, lymph node metastasis, and invasion of nerves and vessels (P < 0.05). The DNA methylation rate in peripheral blood was increasing first and then decreasing in the preoperative, intraoperative and postoperative periods. Moreover, the RARß2 methylation in peripheral blood was shown to be significantly associated with family history of cancer (P = 0.023). CONCLUSION: RARß2 and p16(INK4α) methylation in the peripheral blood in ESCC patients may reflect the tumor-bearing status in the body, and may serve as a valuable marker in assessment of the degree of completeness of surgical resection in ESCC patients.

Silver-coated magnetite-carbon core-shell microspheres as substrate-enhanced SERS probes for detection of trace persistent organic pollutants.

Highly active surface-enhanced Raman scattering (SERS) substrates of Ag nanoparticle (Ag-NP) modified Fe(3)O(4)@carbon core-shell microspheres were synthesized and characterized. The carbon coated Fe(3)O(4) microspheres were prepared via a one-pot solvothermal method and were served as the magnetic supporting substrates. The Ag-NPs were deposited by in situ reduction of AgNO(3) with butylamine and the thickness of the Ag-NP layer was variable by controlling the AgNO(3) concentrations. The structure and integrity of the Fe(3)O(4)@C@Ag composite microspheres were confirmed by TEM, XRD, VSM and UV-visible spectroscopy. In particular, the Ag-NP coated Fe(3)O(4)@carbon core-shell microspheres were shown to be highly active for SERS detections of pentachlorophenol (PCP), diethylhexyl phthalate (DEHP) and trinitrotoluene (TNT). These analytes are representatives of environmentally persistent organic pollutants with typically low SERS activities. The results suggested that the interactions between the carbon on the microsphere substrates and the aromatic cores of the target molecules contributed to the facile pre-concentration of the analytes near the Ag-NP surfaces.

Ultrafast hydrothermal synthesis of high quality magnetic core phenol-formaldehyde shell composite microspheres using the microwave method.

An ultrafast, facile, and efficient microwave hydrothermal approach was designed to fabricate magnetic Fe(3)O(4)/phenol-formaldehyde (PF) core-shell microspheres for the first time. The structure of the Fe(3)O(4)/PF core-shell microspheres could be well controlled by the in situ polycondensation of phenol and formaldehyde with magnetic Fe(3)O(4) clusters as the seeds in an aqueous solution without any surfactants. The effect of synthetic parameters, such as the feeding amounts of phenol, the dosages of formaldehyde, the reaction temperatures, and the microwave heating time, on the morphologies and sizes of the Fe(3)O(4)/PF microspheres were investigated in details. The phenol-formaldehyde shell is found to be evenly coated on Fe(3)O(4) clusters within 10 min of the irradiation. The as-prepared microspheres were highly uniform in morphology, and the method was found to allow the shell thickness to be finely controlled in the range of 10-200 nm. The properties of the composite microspheres were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), thermogravimetic analysis (TGA), Fourier transform infrared (FT-IR) spectra, X-ray diffraction (XRD), and vibrating sample magnetometer (VSM). The as-prepared Fe(3)O(4)/PF microspheres were monodisperse and highly dispersible in water, ethanol, N,N-dimethyformamide, and acetone, a beneficial quality for the further functionalization and applications of the Fe(3)O(4)/PF microspheres.

Redox/pH dual stimuli-responsive biodegradable nanohydrogels with varying responses to dithiothreitol and glutathione for controlled drug release.

A new type of redox/pH dual stimuli-responsive poly(methacrylic acid) (PMAA)-based nanohydrogels was prepared from methacrylic acid and N,N-bis(acryloyl)cystamine crosslinker via distillation-precipitation polymerization. The nanohydrogels could be easily degraded into individual linear short chains (M(n) ≈ 1200, M(w)/M(n) < 1.1) in the presence of 10 mM dithiothreitol (DTT) or glutathione (GSH). Doxorubicin (DOX) as a model anti-cancer drug was high efficiently loaded into the nanohydrogels (up to 42.3 wt%) due to the strong electrostatic interactions between the amine group in doxorubicin (DOX) and the carboxyl groups in the nanohydrogels at a physiological pH. The cumulative release profile of the DOX-loaded nanohydrogels showed a low level of drug release (less than 15 wt% in 24 h) at pH 7.4, and was significantly accelerated at a lower pH (5.0) and reducing environment (over 91 wt% in 5 h), exhibiting an obvious pH/redox dual-responsive controlled drug release capability. The drug release behavior of the DOX-loaded nanohydrogels in the presence of GSH was very different from the DTT as the loaded DOX could be quickly released in the presence of GSH, but not in DTT. The possible reason is the synergic effect of reduction and charge exchange of GSH at a low pH. The dose-dependent cytotoxicity of the DOX-loaded nanohydrogels was studied by the CCK-8 assay; the DOX-loaded nanohydrogels could be taken up quickly by human glioma (U251MG cells) via endocytosis, and then biodegraded to release the loaded drugs, which exhibited a comparably anti-tumor efficacy. These nanohydrogels possess many favorable traits, such as excellent biocompatibility and biodegradability, adequate drug loading capacity, minimal drug release under an extracellular condition (non-reductive), and rapid drug release in response to the intracellular level of pH and reducing potential, which endow them as a promise candidate for delivering anti-cancer drugs.

Tailor-made magnetic Fe3O4@mTiO2 microspheres with a tunable mesoporous anatase shell for highly selective and effective enrichment of phosphopeptides.

Selective enrichment of phosphoproteins or phosphopeptides from complex mixtures is essential for MS-based phosphoproteomics, but still remains a challenge. In this article, we described an unprecedented approach to synthesize magnetic mesoporous Fe(3)O(4)@mTiO(2) microspheres with a well-defined core/shell structure, a pure and highly crystalline TiO(2) layer, high specific surface area (167.1 m(2)/g), large pore volume (0.45 cm(3)/g), appropriate and tunable pore size (8.6-16.4 nm), and high magnetic susceptibility. We investigated the applicability of Fe(3)O(4)@mTiO(2) microspheres in a study of the selective enrichment of phosphopeptides. The experiment results demonstrated that the Fe(3)O(4)@mTiO(2) possessed remarkable selectivity for phosphopeptides even at a very low molar ratio of phosphopeptides/non-phosphopeptides (1:1000), large enrichment capacity (as high as 225 mg/g, over 10 times as that of the Fe(3)O(4)@TiO(2) microspheres), extreme sensitivity (the detection limit was at the fmol level), excellent speed (the enrichment can be completed in less than 5 min), and high recovery of phosphopeptides (as high as 93%). In addition, the high magnetic susceptibility allowed convenient separation of the target peptides by magnetic separation. These outstanding features give the Fe(3)O(4)@mTiO(2) composite microspheres high benefit for mass spectrometric analysis of phosphopeptides.

Toward designer magnetite/polystyrene colloidal composite microspheres with controllable nanostructures and desirable surface functionalities.

An effective method was developed for synthesizing magnetite/polymer colloidal composite microspheres with controllable variations in size and shape of the nanostructures and desirable interfacial chemical functionalities, using surfactant-free seeded emulsion polymerization with magnetite (Fe(3)O(4)) colloidal nanocrystal clusters (CNCs) as the seed, styrene (St) as the monomer, and potassium persulfate (KPS) as the initiator. The sub-micrometer-sized citrate-acid-stabilized Fe(3)O(4) CNCs were first obtained via ethylene glycol (EG)-mediated solvothermal synthesis, followed by 3-(trimethoxysilyl)propyl methacrylate (MPS) modification to immobilize the active vinyl groups onto the surfaces, and then the hydrophobic St monomers were polymerized at the interfaces to form the polymer shells by seeded emulsion radical polymerization. The morphology of the composite microspheres could be controlled from raspberry- and flower-like shapes, to eccentric structures by simply adjusting the feeding weight ratio of the seed to the monomer (Fe(3)O(4)/St) and varying the amount of cross-linker divinyl benzene (DVB). The morphological transition was rationalized by considering the viscosity of monomer-swollen polymer matrix and interfacial tension between the seeds and polymer matrix. Functional groups, such as carboxyl, hydroxyl, and epoxy, can be facilely introduced onto the composite microspheres through copolymerization of St with other functional monomers. The resultant microspheres displayed a high saturation magnetization (46 emu/g), well-defined core-shell nanostructures, and surface chemical functionalities, as well as a sustained colloidal stability, promising for further biomedical applications.

Unfavorable clinical implications of circulating CD44+ lymphocytes in patients with nasopharyngeal carcinoma undergoing radiochemotherapy.

BACKGROUND: To evaluate the use of cellular immunity parameters as predictors of therapy response. METHODS: Circulating lymphocytes were measued by flow cytometry in 94 nasopharyngeal carcinoma (NPC) patients following radiochemotherapy. RESULTS: Significantly decreased percentage of CD3(+), CD4(+), and CD8(+) lymphocytes, significantly increased proportion of CD44(+), CD25(+), NK lymphocytes, and an increased CD4(+)/CD8(+) ratio were indicated in NPC patients as compared with healthy controls. Circulating CD44(+) lymphocytes in both the N2/N3 and III/IV groups were significantly increased as compared to the N0/N1 and I/II groups, respectively (P<0.05). A significant decrease in CD19(+) lymphocytes was observed in the III/IV group as compared with the I/II group (P<0.05). After radiochemotherapy, NPC patients had significantly (P<0.05) decreased percentages of CD4(+), CD44(+), and CD19(+) lymphocytes and a decreased CD4(+)/CD8(+) ratio, whereas the mean percentages of CD8(+) and NK lymphocytes were significantly (P<0.05) increased. However, compared with the pre-radiochemotherapy values, no significant (P>0.05) changes in CD3(+) or CD25(+) lymphocytes were observed in the NPC-treated group. Follow-up analysis indicated significantly lower DFS for patients with high CD44(+) lymphocytes compared to those with low CD44(+) lymphocytes after radiochemotherapy. CONCLUSION: Circulating CD44(+) lymphocytes seems to be a promising criterion to predict survival in NPC patients undergoing radiochemotherapy.

Detecting trace melamine in solution by SERS using Ag nanoparticle coated poly(styrene-co-acrylic acid) nanospheres as novel active substrates.

A systematic study for the preparation of Ag nanoparticle (Ag-NP) coated poly(styrene-co-acrylic acid) (PSA) composite nanospheres by in situ chemical reduction is reported. The experimental results showed that the reaction temperature and the surface coverage of the -COOH determined the surface coverage and grain size of Ag nanoparticles on the PSA nanospheres. The surface enhanced Raman spectroscopy (SERS) sensitivity was investigated using 4-hydroxythiophenol (4-HBT) as the model probe in the solution of composite nanospheres stabilized by polyvinylpyrrolidone (PSA/Ag-NPs/PVP), with the detection limit of about 1 × 10(-6) M. Potential application of the new SERS substrate was demonstrated with the detection of melamine, and the detection limit was about 1 × 10(-3) M. Chemical noises from PVP and other impurities were observed and attributed mainly to the competitive adsorption of PVP on the surfaces of Ag-NPs. After tetrahydrofuran washing of the PSA/Ag-NPs/PVP substrates that removed the PVP and other residuals, the signal/noise levels of SERS were greatly improved and the detection limit of melamine was determined to be 1 × 10(-7) M. This result indicated that the new PSA/Ag-NPs system is highly effective and can be used as the SERS-active substrate for trace analysis of a variety of drugs and food additives.