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Atypical chemokine receptor 3 (ACKR3) has emerged as a key player in various biological processes. Its atypical “intercepting receptor” properties have established ACKR3 as the major regulator in the pathophysiological processes in many diseases. In this study, we investigated the role of ACKR3 activation in promoting colorectal tumorigenesis. We showed that ACKR3 expression levels were significantly increased in human colon cancer tissues, and high levels of ACKR3 predicted the increased severity of cancer. In Villin-ACKR3 transgenic mice with a high expression level of CKR3 in their intestinal epithelial cells, administration of AOM/DSS induced more severe colorectal tumorigenesis than their WT littermates. Cancer cells of Villin-ACKR3 transgenic mice were characterised by the nuclear β-arrestin-1 (β-arr1)-activated perturbation of rRNA biogenesis. In HCT116 cells, cotreatment with CXCL12 and AMD3100 selectively activated ACKR3 and induced nuclear translocation of β-arr1, leading to an interaction of β-arr1 with nucleolar and coiled-body phosphoprotein 1 (NOLC1). NOLC1, as the phosphorylated protein, further interacted with fibrillarin, a conserved nucleolar methyltransferase responsible for ribosomal RNA methylation in the nucleolus, thereby increasing the methylation in histone H2A and promoting rRNA transcription in ribosome biogenesis. In conclusion, ACKR3 promotes colorectal tumorigenesis through the perturbation of rRNA biogenesis by the β-arr1-induced interaction of NOLC1 with fibrillarin.

Structure–property relationship for fluorophores with favorable nonlinear optical (NLO) properties are promising topics in organic chemistry and material science. Herein, a series of terthiophene-o-carborane dyads and triads covalently linked with different end-capping styles were readily synthesized and comprehensively investigated. Quantitative values of the crystal and packing structures, photophysical parameters including aggregation-induced emission (AIE) and two-photon absorption (2PA) were provided. Significant impact of carborane unit for introducing the AIE characteristic has been investigated in contrast to the parent oligothiophene. All the obtained fluorophores exhibit maximum absorption around 370 nm in THF and emit bright reddish photoluminscence with absolute fluorescence quantum yields above 16% in solid states. Intramolecular charge communication between oligothiophene and carborane plays important roles in the related NLO properties. These results are supported well by the time-dependent DFT theoretical calculations. Effective 2PA cross sections (δ2PA= 95–355 GM@650 nm) and transition dipole moments of the derivatives are variable for different end-capping styles. Their potential applications as optical limiting materials based on the 2PA mechanism in solutions and doped PDMS films were further evaluated. Taken together, this work provides an understanding of their structure–property relationship, and flexible PDMS films as outstanding candidates for practical applications in optical limiting.

Although it is widely used in industry and food products, formic acid can be dangerous owing to its corrosive properties. Accurate determination of formic acid would not only benefit its qualified uses but also be an effective way to avoid corrosion or injury from inhalation, swallowing, or touching. Herein, we present a nanofilm-based fluorescent sensor for formic acid vapor detection with a wide response range, fast response speed, and high sensitivity and selectivity. The nanofilm was synthesized at a humid air/dimethyl sulfoxide (DMSO) interface through dynamic covalent condensation between two typically designed building blocks, de-tert-butyl calix[4]arene-tetrahydrazide (CATH) and 4,4′,4″,4‴-(ethene-1,1,2,2-tetrayl)tetra-benzaldehyde (ETBA). The as-prepared nanofilm is uniform, flexible, fluorescent, and photochemically stable. The thickness and fluorescence intensity of the nanofilm can be facilely adjusted by varying the concentration of the building blocks and the sensing performance of the nanofilm can be optimized accordingly. Based on the nanofilm, a fluorescent sensor with a wide response range (4.4 ppt–4400 ppm) for real-time and online detection of formic acid vapor was built. With the sensor, a trace amount (0.01%) of formic acid in petroleum ether (60–90 °C) can be detected within 3 s. Besides, fluorescence quenching of the nanofilm by formic acid vapor can be visualized. It is believed that the sensor based on the nanofilm would find real-life applications in corrosion and injury prevention from formic acid.

Hexamethylenetetramine (HMTA) is extensively used in the defense industry, medicines, food, plastics, rubber, and other applications. Traditional organic synthesis of HMTA relies on ammonia derived from the Haber process at high temperatures and pressures. In contrast, electrochemical methods enable a safe and green one-pot synthesis of HMTA from waste NO3–. However, HMTA synthesis through the electrochemical method is challenging owing to the complex reaction pathways involving C–N bond construction and ring formation. In this study, HMTA was efficiently synthesized over electrochemical oxidation-derived copper (e-OD-Cu), with a yield of 76.8% and a Faradaic efficiency of 74.9% at −0.30 VRHE. The catalytic mechanism and reaction pathway of HMTA synthesis on e-OD-Cu were investigated through a series of in situcharacterization methods and density-functional theory calculations. The results demonstrated that the electrocatalytic synthesis of HMTA involved a tandem electrochemical–chemical reaction. Additionally, the results indicated that the presence of Cu vacancies enhanced substrate adsorption and inhibited the further hydrogenation of C═N. Overall, this study provides an electrocatalytic method for HMTA synthesis and an electrochemical strategy for constructing multiple C–N bonds.

The modular construction of defect-free nanofilms with a large area remains a challenge. Herein, we present a scalable strategy for the preparation of calix[4]pyrrole (C[4]P)-based nanofilms through acryl hydrazone reaction conducted in a tetrahydrazide calix[4]pyrrole (CPTH)-based self-assembled layer at the air/DMSO interface. With this strategy, robust, regenerable, and defect-free nanofilms with an exceptionally large area (∼750 cm2) were constructed. The thickness and permeability of the film systems can be fine-tuned by varying the precursor concentration or by changing another building block. A typical nanofilm (C[4]P-TFB, ∼67 nm) depicted high water flux (39.9 L m–2h–1under 1 M Na2SO4), narrow molecular weight cut-off value (∼200 Da), and promising antifouling properties in the forward osmosis (FO) process. In addition, the nanofilms are stable over a wide pH range and tolerable to different organic solvents. Interestingly, the introduction of C[4]P endowed the nanofilms with both outstanding mechanical properties and unique group-selective separation capability, laying the foundation for wastewater treatment and pharmaceutical concentration.

Photochemical synthesis, in which light is used as an indispensable reagent, is recognized as a green technique for organic synthesis and has been paid extensive attention. In this laboratory experiment for chemistry classes, a photoinduced C–C coupling reaction is introduced, which can be conducted under mild conditions at room temperature. Generally, this reaction requires no photoredox catalyst and only 2 equiv of triethylamine with common LED light (400 nm) as the light source. Here, we report the photochemical synthesis of a favorable fluorophore (4MPB) with high yields (∼80%) using 4-iodobenzoate and N-methylpyrrole as the representative reagents in an undergraduate laboratory experiment. Importantly, all participating students were excited about the fluorophores that they synthesized and gained the basic principles of photoluminescence. This experiment is safe, easy to conduct, and cost-effective, and it received positive feedback from the students. The exercise reinforces their skills in photochemical synthesis and introduces students to the significance and importance of light in chemistry, which is a fascinating field in chemical research.

Aberrant sphingolipid metabolism has been implicated in chemoresistance, but the underlying mechanisms are still poorly understood. Herein we revealed a previously unrecognized mechanism of 5-fluorouracil (5-FU) resistance contributed by high SphK2-upregulated dihydropyrimidine dehydrogenase (DPD) in colorectal cancer (CRC), which is evidenced from human CRC specimens, animal models, and cancer cell lines. TMA samples from randomly selected 60 CRC specimens firstly identified the clinical correlation between high SphK2 and increased DPD (p< 0.001). Then the regulatory mechanism was explored in CRC models of villin-SphK2 Tg mice, SphK2−/−mice, and human CRC cells xenografted nude mice. Assays of ChIP-Seq and luciferase reporter gene demonstrated that high SphK2 upregulated DPD through promoting the HDAC1-mediated H3K56ac, leading to the degradation of intracellular 5-FU into inactive α-fluoro-β-alanine (FBAL). Lastly, inhibition of SphK2 by SLR080811 exhibited excellent inhibition on DPD expression and potently reversed 5-FU resistance in colorectal tumors of villin-SphK2 Tg mice. Overall, this study manifests that SphK2highconferred 5-FU resistance through upregulating tumoral DPD, which highlights the strategies of blocking SphK2 to overcome 5-FU resistance in CRC.

Portable, miniaturized, and inexpensive detectors are in high demand for detecting and discriminating volatile organic compounds (VOCs). Sensor array design and exploitation are two key issues for new detector development. In contrast to the most reported plane-shaped sensor array for gaseous analyte sensing, here we report a column-shaped fluorometric sensor array by using fluorophore-loaded silica particles (∼40 μm) filled capillary. In the design, the capillary serves as test chamber and facilitates visualization. The orifices of the capillary were used as inlet and outlet for gaseous analyte. Sensing modules are installed in series, which lays foundation for their even and effective contact with the gaseous analyte. Meanwhile, further capsulation could be avoided. Silica particles were chosen as carries due to their preferred adsorption behavior to VOCs. By choosing four typical fluorophores (PBI-CB, Py-CB-Ph, Py-At, and NA-Ch) as sensing units, a 4-element fluorometric sensor array was achieved. Fluorescence of the array varied when different alcohol vapors were pumped in. The six tested alcohols could not only be distinguished as primary, secondary, or tertiary, but also be identified individually. The array had good reproducibility in visualization of the six alcohols. In addition, the orders of the fluorophores can be changed as desired. It is believed that the proofed concept provides not only a totally new design of sensor array but also contributes a new strategy for the discrimination of the alcohols as examined.

Film-based fluorescence sensing is recognized as one of the most optimized techniques for trace analysis of chemicals in the air after the invention of ion mobility spectrometry. The performance of the technique is highly dependent on the design of the film. This paper reports a new fluorescent film which shows unprecedented and discriminative sensing performance to the presence of phenol, o-cresol, m-cresol, and p-cresol in the air with an ultralow detection limit as low as 0.4, 0.3, 10, and 0.8 ppt, respectively. The film was designed via combination of the advantages of aggregation-induced emission (AIE) and those of intramolecular charge transfer (ICT), where the former provides the opportunity to avoid the widely encountered aggregation-caused quenching (ACQ) effect and the latter allows sensitive sensing of the microenvironment change of the film. The biggest challenge of the design is to find a fluorophore possessing both AIE and ICT effects. Fortunately, a newly synthesized biphenyl derivative of o-carborane capped with azetidine moiety (BZPCarb) shows the properties as expected. Importantly, the fluorophore is photochemically stable, a prerequirement for multiple uses of a film device. In addition, the nonplanar structure of the fluorophore is also favorable for film sensing as it could form porous films owing to screening of dense stacking of the molecules. It is the merits that make BZPCarb-based film show outstanding sensing and discriminative performances. Based on the fluorophore and the design, a conceptual high-performance fluorescent vapor sensor for phenolic compounds was developed.

New kinds of mechanically robust, porous polymeric materials with varied internal structures were produced using a newly designed water-in-oil (W/O) gel emulsion as a template. The density, internal structure, and mechanical properties of the porous materials can be easily and largely adjusted by varying the water content and the stabilizer (SiO2) amount in the relevant gel emulsions. Specifically, the density and compressive strength could be changed from 0.19 to 0.96 g/cm3and from a few MPa to more than 100 MPa, respectively. Importantly, the materials obtained demonstrated unusual low-frequency sound absorption properties. In addition, the gel emulsions created can be used as a new kind of 3D printable material, which allows polymerization after printing. In this way, complicated architectures can be produced.

In situ, on line, noncontact, and fast monitoring of the compositions of ethanol–water mixtures via vapor-phase sampling has remained a challenge for years. In this work, we report for the first time a film-based fluorescent sensor showing unprecedented ability to discriminate the compositions of ethanol–water mixtures. Importantly, ethanol contents in the mixtures can vary from 0 to 100% (v/v), the response time is less than 2 s, and the sensing is fully reversible. More importantly, the monitoring was performed via vapor-phase sampling, avoiding sample contamination. The principle behind it is ascribed to the big difference in the fluorescent quantum yield of the sensing unit, a newly designed and synthesized monosubstituted fluorescent o-carborane derivative (ZPCarb), in the two solvents. In addition, the sensor as developed was successfully used for the determination of ethanol contents in four commercial liquors, suggesting its potential application in the quality control of beverages, in monitoring fermentation processes, and in other processes.

AbstractIn recent years, how to carry out effective high technology investment risk prediction in the financial market with constraints has attracted the attention of scholars. In this paper, partial linear regression model is used to describe and analyze the stock data with inconsistent length in different markets. And high technology investment risk prediction is carried out on the basis of improved yield and covariance matrix. The results of the numerical example show that the high technology investment risk prediction using partial linear regression analysis under inequality constraints has better performance than the investment model using the ordinary least square regression when the length of stock data is inconsistent.

The supramolecular approach plays a pivotal role in the construction of smart and functional materials due to the reversible nature of noncovalent interactions. In the present work, two compounds, cholesterol-functionalized calix[4]pyrrole (CCP) and perylene bisimide diacid (PDA), were synthesized. Little fluorescence is observed in the ethanol solution of the mixture of CCP and PDA, while the solution turns fluorescent upon introduction of ammonia, which is attributed to the formation of a supramolecular ensemble, PDA/(CCP)2/NH3. The fluorescence emission of the as-formed ensemble is sensitive to the presence of phenol, an electron-rich analyte. Interestingly, the sensing can also be observed in the film state, and the relevant detection limit (DL) is lower than 1 ppb. Moreover, the sensing could also be performed in a visualized manner. Upon the basis of the findings, a sensor device with instant response and good reversibility was developed. Further studies revealed that the as-developed fluorescent ensemble is also sensitive to the presence of TNT, an electron-poor compound. The DL for this sensing is ∼80 nM. To our knowledge, this is the first report that a fluorescent sensor could be used for phenol sensing in the vapor state, and for sensing of both electron-rich and electron-poor analytes in solution state. It is believed that the present study presents a distinctive example that demonstrates how smart sensing is realized via combination of the host–guest chemistry of calix[4]pyrrole and the aggregation and disaggregation property of PBI derivatives.

Aiming at the degradation-resistant characteristic of alkali lignin, gasification of alkali lignin in supercritical water was carried out in a batch reactor with Ru/C nanotubes as catalyst. The effects of temperature, water density, time, reactant concentration, catalyst amount as well as the catalytic efficiency on the gasification of alkali lignin were examined. The optimum conditions obtained with single factor analysis are as follows: reaction temperature 600°C, water density 0.1284 g/cm3, reaction time 60 min, reactant concentration 3.0%, and catalyst amount of 0.5 (g/g alkali lignin). The results show that high temperature, high water density (or pressure), long reaction time, low reactant concentration and moderate amount of catalyst will be in favor of the gasification of alkali lignin in supercritical water. The alkali lignin gasification efficiency and carbon conversion reaches 73.74% and 56.34%, respectively, under the optimal reaction conditions. Hydrogen production capacity is also significantly improved.

Ion chromatography (IC) method was applied to detection of fluorine in the atmosphere calm wind conditions at the area around the yellow phosphorus enterprise. The results indicated that the recovery of standard addition of Fluroide is 96.7%~100.6%. It gives a linear response of chromatographic peak height with respect to the fluoride in the range of 1~25 μg/mL, and the coefficient correlations R value is 0.9994. The concentration of Fluorine in the surrounding of yellow phosphorus enterprise ranging from 100~1500 m varies from 0.641~0.070 mg/m3. The relative standard deviation (RSD) of this method is between 2.10%~0.50%. This method is sensitivity and selectivity, low disturbance, and it is considered as a promising method for the detection of Fluorine surrounded yellow phosphorus enterprise.

The difficulty of the signal processing is not the acquisition of the signals, but how to get the reasonble interpretations from the signals. Since the 1960s, Wavelet Transform, Fast Fourier method and other theoryies have done some works by some innovative processing methods to achieve a breakthrough. But for their limitions, these methods can not achieve a complete separation if the there are two or more signals in one time domain or frequency domain. In this article, a new engineering signal processing method-pattern filter method has is introduced, by which the signal extraction, sepration and noise reduction can be achieved successfully. Experiments show that this method can not only make a reasonable separation of the various vibration signals, but also give the typical signal extractions and model building ways.

A novel, facile, and effective method for modification of SiNWs or SiNW arrays has been developed. In this method, reaction between reductive Si–H bonds on the surface of SiNWs and the aldehyde group containing in organic molecules has been used for immobilization of organic molecules onto the surface of SiNW arrays. The method is time saving and can be operated at room temperature without any other complex reaction requirement. Fluorescence images, XPS, fluorescence spectra, and IR spectra were used for characterization of the modification. Through this method, a SiNW array-based pH sensitive chip was realized by covalently immobilizing 5-aminofluorescein molecules onto the surface of SiNW arrays with glutaraldehyde as linker molecules. Fluorescence intensity of the chip increased with increasing of pH value and a linear relationship between fluorescence intensity and pH values was acquired. In addition, the chip has been successfully used for real-time and in situ monitoring of extracellular pH changes for live HeLa cells and the result exhibited fine resolution of time and space.

The cycle of each vibration component of a mixed signal is a very important parameter for reciprocating mechanical vibration signal processing. The cycle determination also has an important influence to obtain the typical characteristics of every sub-signal, to achieve the fault detection and diagnosis of the equipment. But signals acquired at the scene tend to a mixture of a variety of vibration components that have their own periodic characteristics. This paper mainly proposes a method based on the conception of the basic operation unit(BOU) for mechanical vibration signal processing, and the principles and processes of this method are described in detail. Simulation method is introduced in order to explain this principles. Furthermore, A Delphi programming is developed to realize this simulation implementation, and simulation results are demonstrated to fully verify its correctness. Finally, a method to quickly determine the various vibration component cycles is put forward.

How to realize signal modeling and vibration signal characteristic extraction is a very significant topic. A large amount of drilling pump vibration signals were acquired from the indoor tests. The startup signals with time consistency were segmented from these measurement signals and analyzed in detail. There are mainly such five types of vibrations in the startup signals as the pump body’s vibration, whistle, shocks in moving parts, and impacts of the value lifted off or dropped on the seat, friction or grinding between moving parts. The pump body’s vibration and whistle have good time-frequency characteristics and change very regularity, which are defined as the startup vibration in this paper. The pump body’s vibration signals are modeled by OFMM method. After to exclude the OFMM modeling signal, the remaining signal was separated into different integrated components according to their vibration sources by PFM method, a HMM whistle vibration model based on PFM parameters was achieved. Furthermore, A combination of OFMM and HMM model is used to describe the pump startup vibration. Realistic simulation on the pump’s startup vibration has been achieved. Signal simulation was also carried out by use of this combination model. This approach is expected to become a powerful tool for drilling pump’s startup vibration signal analysis and modeling.

A large amount of drilling pump vibration signals are acquired and decomposed optimally into time-frequency atoms by the Pattern Filter Method. All of these time-frequency atoms are falling into the multidimensional statistical cube which is formed by the time-frequency atomic parameter (α,f,φ,A) space with certain interval length. The atoms in every cube are counted and the results are stored in a database. When keeping any two parameters in a certain range, the quantitative distribution contour maps in the plane of other two parameters are demonstrated by the Graf software tool, then all sub-space results were aggregated to construct the macro-views of the BOU quantity distribution in the four-dimensional space ,meanwhile the quantitative distribution of these atoms are investigated, the distribution characteristics for various vibration signals of drilling pump are obtained and all atoms are classified according to their clustering state in this parametric space. Furthermore, every special signal corresponding to the parametric feature clustering of atoms in this multidimensional space have been identified. The desired results have been achieved in signal identification and drilling pump fault diagnosis by use of these consequences.

Highly oriented arrays of one-dimensional Ge cone-like nanostructures were prepared in the aqueous solution of HF and H2O2by a facile chemical etching method. The morphologies of the cone-like nanostructure arrays can be readily controlled by modulating the compositions, temperature, and concentrations of the etching solution as well as the etching duration. It is suggested that the positive charged holes play a critical role in the formation of the present cone-like nanostructures. By covalently bonding the fluorescein derivatives onto the surfaces of the Ge nanostructures, a fluorescent pH sensor with a good sensitivity and selectivity was achieved.

With the help of digital audio technology, fault diagnosis and quick identification of multi-channel synchronous vibration signals acquired from a triplex pump in well site were achieved. A characteristic model of fluid end’s vibration for this pump was established and further verified by indoor systematic experiments. The source of various vibration components was determined, statistic relationships between these components in different conditions were regressed, and typical sub-signals excited by pump valve movement were also modeled by the use of the basic operation unit segmentation and optimal frequency matching method. These works provide a favorable tool for identifying the pump vibration signals, fault diagnosis, and dynamic modeling of drilling reciprocating pump in future. Such results also have a good contribution to study vibration problems on other types of reciprocating machinery.

Our previous studies demonstrated that manumycin A, a farnesyltransferase inhibitor, induced apoptosis of anaplastic thyroid cancer cells via the intrinsic apoptosis pathway and induced reactive oxygen species (ROS), which mediated DNA damage. In this study, we investigated the hypothesis that the mechanism of apoptosis induced by manumycin in anaplastic thyroid cancer cells fits the general pattern of the “xenobiotic apoptosis pathway,” the hallmarks of which are induction of oxidative stress, mitogen-activated protein kinase (MAPK) signaling, and cytochrome c release, which activates the intrinsic apoptosis pathway. We found that manumycin reduced intracellular glutathione and generated ROS: nitric oxide and superoxide anions. Manumycin-induced apoptosis correlated with increase in ROS. Quenching of ROS with N-acetyl-L-cysteine prevented cytochrome c release by manumycin. Manumycin induced phosphorylation of p38 MAPK, which was blocked by N-acetyl-L-cysteine. p38 MAPK may be an important signaling mediator in the activation of the intrinsic apoptotic pathway by manumycin because the p38 MAPK inhibitor SB203580 inhibited cytochrome c release and activation of caspase-3 by manumycin. In conclusion, manumycin activated the intrinsic apoptosis pathway via activation of p38 MAPK by oxidative stress. The mechanism of apoptosis induced by manumycin fits the emerging general pattern for apoptosis induced by xenobiotics.

The growth behavior and surface morphology of a rough film system, deposited on silicone oil drop surfaces by a r.f. magnetron sputtering method, have been studied. An anomalous film growth relaxation is observed during the deposition process. The relaxation rate is extremely sensitive to the substrate temperature. The surface morphology at the micrometer length scale is very susceptible to the substrate temperature, the incident r.f. capacity, and the nature of the solid substrate on which the oil drop is dripped. A discussion on the physical origins of these phenomena is also presented.

Based on three rationally designed pyrrole-appended o-carborane derivatives, we present that fluorescence properties of crystalline materials are highly dependent on intermolecular interaction and steric hinderance. Though the three molecules are similar in structure, single crystals of the three compounds showed obvious difference in molecular stacking and fluorescence behavior. Systematic studies indicate that fluorescence quantum yields, thermo-response as well as mechano-response are highly dependent on intermolecular interaction and steric hindrance. In the three crystalline materials, the CB-NMe crystals with weaker intermolecular interaction and looser molecular packing showed superior fluorescence quantum yield and temperature sensitivity. Accordingly, surface temperature detection strip with favorable reversibility is prepared by doping CB-NMe into the polymer. In addition, the CB-NMe aggregates can be used for monitoring bovine serum albumin (BSA) denaturation, as temperature response of the aggregates can be reversed when co-assembled with BSA.

We investigate the Casimir effect at a finite temperature in the electromagnetic Rindler space, and we find that the Casimir energy is proportional to T^4d^2 in the high-temperature limit, where T≈27?°C is the temperature and d≈100?nm is a small cutoff. We propose to make metamaterials to mimic the Rindler space and measure the predicted Casimir effect. Because the parameters of metamaterials we proposed are quite simple, this experiment would be easily implemented in the laboratory.

Tungsten oxide thin films were electrochemically deposited onto gallium nitride for the first time and directly used for the fabrication of an acetone sensor. This sensor could operate at room temperature and had high sensitivity, fast response, and long-term stability. Moreover, the detection limit of the sensor could reach 0.1 ppm, implying its potential application in non-invasive detection of diabetes.Amorphous films of WO3are electrodeposited on GaN for the first time and characterized by SEM, TEM, XRD, and EDS. The gas sensor based on WO3films exhibited high sensitivity (6.43), quick response (19 s), fast recovery time (11 s), and good selectivity to acetone gas at room temperature. The as-prepare sensors are promising for non-invasive detection of diabetes.

Objective The myelodysplastic syndromes (MDS) comprise a heterogeneous group of clonal hematopoietic stem cell disorders, while, immunological abnormalities are frequently observed in patients with MDS. Several reports revealed that about 10% of MDS patients have clinical autoimmune disorders like skin vasculitis, rheumatic disease, or autoimmune hemolytic anemia. Furthermore, serological immunological abnormalities like hyper- or hypogammaglobulinemia, positivities of antinuclear antibody, positivities of direct Coombs test, or inverted CD4/8 ratios were found in 18–65% of patients with MDS. Recently immunosuppressive therapies including prednisolone, antithymocyte globulin, and cyclosporin A (CsA) are used to treat cytopenia in some patients with MDS. But it isn’t very clear the immunosuppressive mechanism in MDS and the value of the treatment. To analyze the content of signal joint Tcell receptor excision DNA circles signal joint T cell receptor excision DNA circles(sjTRECs) within peripheral blood mononuclear cells (PBMCs), thereby to infer the level of naive T cells and the recent thymic output function in patients with myelodyspoastic syndrom. Methods Quantitative detection of sjTRECs in DNA of peripheral blood mononuclear cells from 13 normal individuals and 8 patienets were performed by real-time polymerase chain reaction (PCR) and TaqMan technique. Results The median value of sjTRECs copies P1 000 PBMCs was 4.37±3.64 in normal individuals whereas it was1.07 ±1.40 copies P1 000 PBMCs in myelodysplastic syndrom patients (P <0. 05). Conclusions MDS Patients decrease in recent thymic output function.

Objective