Testosterone promotes the migration, invasion and EMT process of papillary thyroid carcinoma by up-regulating Tnnt1

PURPOSE

To explore the key genes and molecular pathways in the progression of thyroid papillary carcinoma (PTC) promoted by testosterone using RNA-sequencing technology, and to provide new drug targets for improving the therapeutic effect of PTC.

METHODS

Orchiectomy (ORX) was carried out to construct ORX mouse models. TPC-1 cells were subcutaneously injected for PTC formation in mice, and the tumor tissues were collected for RNA-seq. The key genes were screened by bioinformatics technology. Tnnt1 expression in PTC cells was knocked down or overexpressed by transfection. Cell counting kit-8 (CCK-8), colony formation assay, scratch assay and transwell assay were adopted, respectively, for the detection of cell proliferation, colony formation, migration and invasion. Besides, quantification real-time polymerase chain reaction (qRT-PCR) and western blot were utilized to determine the mRNA and protein expression levels of genes in tissues or cells.

RESULTS

Both estradiol and testosterone promoted the growth of PTC xenografts. The key gene Tnnt1 was screened and obtained by bioinformatics technology. Functional analysis revealed that overexpression of Tnnt1 could markedly promote the proliferation, colony formation, migration, invasion, and epithelial-to-mesenchymal transition (EMT) process of PTC cells, as well as could activate p38/JNK pathway. In addition, si-Tnt1 was able to inhibit the cancer-promoting effect of testosterone.

CONCLUSION

Based on the outcomes of bioinformatics and basic experiments, it is found that testosterone can promote malignant behaviors such as growth, migration, invasion and EMT process of PTC by up-regulating Tnnt1 expression. In addition, the function of testosterone may be achieved by activating p38/JNK signaling pathway.

POS0966 DEVELOPMENT AND VALIDATION OF AN ANKYLOSING SPONDYLITIS RISK PREDICTION MODEL USING LONGITUDINAL REAL-WORLD DATA FROM A LARGE INTEGRATED HEALTHCARE DELIVERY SYSTEM

Background

Early detection and diagnosis of Ankylosing spondylitis (AS) is challenging due to heterogeneity in disease presentation, lack of specific biomarkers and high prevalence of mechanical back-pain that is difficult to distinguish from inflammatory back-pain. However, if diagnosed and treated early, the risk of AS complications and disease progression can be slowed.

Objectives

To develop and validate a risk prediction model for early identification of patients at high risk of AS, using a large longitudinal real-world clinical data in the US.

Methods

This retrospective study included all members aged ≥ 21 years with back pain symptoms who were enrolled in the Kaiser Permanente Southern California health plan between 01/2009-12/2013. Patients who presented with back pain symptoms at a physician visit were followed until 12/2020 to see if they subsequently developed AS. The cohort was randomly divided into a training (60%) and a validation (40%) sample. A proportional odds model was specified to create a risk score for AS in the training sample. Best fit model was determined based on Area Under the Curve (AUC) and Akaike Information Criterion (AIC). The cut off threshold of “high-risk” was based on Youden’s (1950) index.1 We assessed the model performance for internal validity using split-samples. The model was further validated using manual chart review of 900 patient records. These 900 records were selected such that 70% (N=630) met the high-risk cut-off and the remainder had scores below the cut-off. We also derived the probability of AS in each chart reviewed case using the method proposed by Feldtkeller et al. (2013) and Rudwaleit et al. (2006).2,3

Results

The cohort comprised 527,509 members with mean age 54 years and majority female (58%). Sixty-six percent were White race and 33% were Hispanic ethnicity. The crude incidence of AS was 1% and increased steadily during the follow-up period (Figure 1). The final risk prediction model included 15 risk factors and had an AUC of 0.72 (Table 1). Using Youden’s index, a cut-off value of 11 or higher was identified as the threshold to define high-risk. No evidence of overfitting to our training sample was observed based on the split-sample analysis. The model validation based on manual chart review of 900 records showed sufficient ability to discriminate between those at high-risk vs those not identified to be high-risk. When a concrete rule out or rule in determination could be made using Feldtkeller et al. approach, our model correctly classified 75% of such records.

Table 1.

Final Model Coefficients and Derived Risk Score

Model CoefficientPr(>|z|)Risk ScoreAge above 45 years0.1460.0111.46Male Sex-0.292<0.001-2.92White Race0.259<0.0012.59Non-Hispanic Ethnicity0.177<0.0011.77Corticosteroid Use (Yes/No)0.235<0.0012.35*NSAID User (Yes/No)0.202<0.0012.02Opioid Analgesic User (Yes/No)0.416<0.0014.16Had Enthesitis (Yes/No)0.298<0.0012.98Had Disorders of the Back (Yes/No)0.973<0.0019.73Had Fatigue and/or Malaise (Yes/No)0.1550.0561.55Had Psoriasis (Yes/No)0.2880.0082.88Had Spondylosis (Yes/No)0.838<0.0018.38Had Synovitis (Yes/No)0.1430.0661.43Had Uveitis (Yes/No)0.6210.0076.21Depression Diagnosis (Yes/No)0.0990.0170.99

* NSAID: Non-steroidal anti-inflammatory drugs

Figure 1.

Cumulative Incidence Over Time (in Days)

Conclusion

To aid early detection, we have developed and validated an AS risk prediction model with an easy to implement scoring system using demographics, medication use and diagnosis data that is routinely collected in clinical practice.

References:

[1]Youden WJ. Index for rating diagnostic tests. Cancer. 1950;3(1):32-35.

[2]Feldtkeller E, Rudwaleit M, Zeidler H. Easy probability estimation of the diagnosis of early axial spondyloarthritis by summing up scores. Rheumatology (Oxford, England). 2013;52(9):1648-1650

[3]Rudwaleit M, Feldtkeller E, Sieper J. Easy assessment of axial spondyloarthritis (early ankylosing spondylitis) at the bedside. Ann Rheum Dis 2006;65:1251-2.

Disclosure of Interests

Aniket Kawatkar Grant/research support from: Novartis, Medac, Esther Yi Employee of: Novartis, Erika Estrada Grant/research support from: Novartis, Jose Pio Grant/research support from: Novartis, Cecilia Portugal Grant/research support from: Novartis, David Yi Grant/research support from: Novartis, Talar Habeshian Grant/research support from: Novartis, David Wei Employee of: Novartis, Steven Lee Grant/research support from: Novartis

[Efficacy of high-voltage long-duration pulsed radiofrequency treatment in patients with neuralgia resulting from failed back surgery syndrome]

Objective: To explore the efficacy and safety of high-voltage long-duration pulsed radiofrequency (PRF) treatment in patients with neuralgia resulting from failed back surgery syndrome (FBSS). Methods: The clinical data of 58 patients diagnosed with neuralgia resulting from FBSS in the Department of Pain Medicine, Peking University Third Hospital from January 2017 to January 2020 were retrospectively analyzed. The patients were divided into two groups according to the treatment method. Experimental group (n=28) underwent high-voltage long-duration PRF therapy, using ultrasound and X-ray guidance to target the spinal nerve of the affected side, while control group (n=30) was applied with the standard pulsed radiofrequency therapy. Visual analogue scale (VAS), Oswestry disability index (ODI), 36-item short form health survey (SF-36), patient health questionnaire (PHQ-9) before treatment and at 1 week, 1 month, and 6 months after treatment were recorded. Meanwhile, postprocedural complications and adverse reactions were also collected. Results: VAS, ODI, SF-36 and PHQ-9 scores at 1 week, 1 month, and 6 months after treatment were significantly improved in both groups compared with their respective pre-treatment baseline scores (all P<0.01). The differences of VAS, ODI, and PHQ-9 scores between the two groups were not statistically significant at 1 month after treatment (all P>0.05). However, VAS, ODI, and PHQ-9 scores were lower in experiment group than those in control group at 6 months after treatment (all P<0.05). The marked improvement rate and total effective rate at 6 months after treatment in experiment group was 78.6% (22/28) and 92.9% (26/28), respectively, which were higher than that of control group [60.0% (18/30) and 83.3% (25/30), respectively], but the differences were not statistically significant (both P>0.05). No serious complications occurred during the whole period of treatment. Conclusions: Both treatments can effectively relieve the lower limb neuralgia. High-voltage long-term PRF has better efficacy and longer duration than standard PRF.

A setup to measure the temperature-dependent heating power of magnetically heated nanoparticles up to high temperature

Magnetic heating, namely, the use of heat released by magnetic nanoparticles (MNPs) excited with a high-frequency magnetic field, has so far been mainly used for biological applications. More recently, it has been shown that this heat can be used to catalyze chemical reactions, some of them occurring at temperatures up to 700 °C. The full exploitation of MNP heating properties requires the knowledge of the temperature dependence of their heating power up to high temperatures. Here, a setup to perform such measurements is described based on the use of a pyrometer for high-temperature measurements and on a protocol based on the acquisition of cooling curves, which allows us to take into account calorimeter losses. We demonstrate that the setup permits to perform measurements under a controlled atmosphere on solid state samples up to 550 °C. It should in principle be able to perform measurements up to 900 °C. The method, uncertainties, and possible artifacts are described and analyzed in detail. The influence on losses of putting under vacuum different parts of the calorimeter is measured. To illustrate the setup possibilities, the temperature dependence of heating power is measured on four samples displaying very different behaviors. Their heating power increases or decreases with temperature, displaying temperature sensibilities ranging from -2.5 to +4.4% K^-1. This setup is useful to characterize the MNPs for magnetically heated catalysis applications and to produce data that will be used to test models permitting to predict the temperature dependence of MNP heating power.

[Analysis of anxiety, depression and related factors in patients with chronic lumbocrural pain before minimally invasive surgery]

OBJECTIVE

To investigate anxiety and/or depression status of patients with chronic lumbocrural pain, and to further analyze related risk factors of anxiety and/or depression .

METHODS

Retrospective analysis of the medical data of patients who suffered from chronic lumbocrural pain caused by lumbar disc herniation and/or lumbar spinal stenosis and received minimally invasive surgery from March 2018 to April 2018. General data (including age, gender, education levels, past history, sleep order and medical insurance), numeric rating scale(NRS), Japanese Orthopedic Association(JOA) back pain scale and hospital anxiety and depression scale(HADS) were collected for analysis. The basic demographic data and clinic data were analyzed, possible related risk factors associated were analyzed by univariate analysis, and multivariate Logistic regression analysis was further used to find the relative independent risk factors and included all the predictive variables with P values less than 0.05 as covariates.

RESULTS

A total of 91 patients met the inclusion criteria and finished this study, the mean HADS score for anxiety was 8.1±4.2, 48(52.7%) respondents were screened positive for anxiety, while the rest 43(47.3%) patients had negative anxiety state, the mean HDDS score for depression was 6.9±4.9, 38(41.8%) respondents were screened positive for depression, and the rest 53(58.2%) patients were not depressed, and 56(61.5%) patients experienced anxiety or depression. There were significant difference in sleep disorder, JOA score and leg NRS score between the patients with and without anxiety(P<0.05), and the significant differences were also found in age, sleep disorder and JOA score between the patients with and without depression(P<0.05), Logistic regression analysis further showed that the JOA score and sleep disorder were risk factors for anxiety, and the JOA score was risk factor for depression.

CONCLUSION

Patients with chronic lumbocrural pain are often accompanied by anxiety and/or depression before minimally surgery, the low JOA score and sleep disturbance increased the risk of presenting anxiety, and the low JOA score increased the risk of developing depression. It is necessary to evaluate mental status and related risk factors before surgery.

De novo transcriptome characterisation of two auxin-related genes associated with plant growth habit in Astragalus adsurgens Pall

Astragalus adsurgens Pall., a perennial legume native to China, is commonly used as a forage crop. And it has great value for sustainable development of grasslands in arid and semi arid regions. However, to date, little is known regarding the A. adsurgens genome, and no studies have determined whether it would be possible to improve the germplasm of A. adsurgens through genetic modification. In this study, we used an RNA-seq protocol to generate a de novo transcriptome including 151,516 unigenes of A. adsurgens. We compared the transcriptomes of A. adsurgens having different growth habits (prostrate/erect) and identified 14,133 single nucleotide polymorphism sites (SNP) in 8,139 unigenes. Differential expression gene (DEG) analysis suggested that 10,982 unigenes were up-regulated in the prostrate plant relative to the erect plant, while 10,607 unigenes were down-regulated. Of the 21,589 DEG, Unigene72782_All (LAX4) and CL12494.Contig3_All (TIR1), an auxin transporter gene and an auxin transport inhibitor gene, respectively, were predicted to influence the growth habit of A. adsurgens, which were verified by qRT-PCR in these phenotypes. These results suggest that auxin transport was more active in the prostrate plant than in the erect plant, resulting in asymmetric distribution of auxin that affects the growth habit of A. adsurgens. Overall, this study may provide a basis for future research on key genes in A. adsurgens and may deepen our understanding of the molecular mechanisms regulating plant growth habit.

Genomic and epidemiological monitoring of yellow fever virus transmission potential

The yellow fever virus (YFV) epidemic in Brazil is the largest in decades. The recent discovery of YFV in Brazilian Aedes species mosquitos highlights a need to monitor the risk of reestablishment of urban YFV transmission in the Americas. We use a suite of epidemiological, spatial, and genomic approaches to characterize YFV transmission. We show that the age and sex distribution of human cases is characteristic of sylvatic transmission. Analysis of YFV cases combined with genomes generated locally reveals an early phase of sylvatic YFV transmission and spatial expansion toward previously YFV-free areas, followed by a rise in viral spillover to humans in late 2016. Our results establish a framework for monitoring YFV transmission in real time that will contribute to a global strategy to eliminate future YFV epidemics.

Ambipolar transport and magneto-resistance crossover in a Mott insulator, Sr2IrO4

Electric field effect (EFE) controlled magnetoelectric transport in thin films of undoped and La-doped Sr₂IrO₄ (SIO) is investigated using ionic liquid gating. The temperature dependent resistance measurements exhibit insulating behavior in chemically and EFE doped samples with the band filling up to 10%. The ambipolar transport across the Mott gap is demonstrated by EFE tuning of the channel resistance and chemical doping. We observe a crossover from high temperature negative to low temperature positive magnetoresistance around  ∼80-90 K, irrespective of the filling. This temperature and magnetic field dependent crossover is discussed in the light of conduction mechanisms of SIO, especially variable range hopping (VRH), and its relevance to the insulating ground state of SIO.

Effects of Rhodium Doping on the Microstructures and Photocatalytic Performances of TiO2 Powders

Rh-doped TiO2 powder was synthesised by the sol-gel method, and its structure and performance were characterised using a variety of techniques. When calcined between 673 K and 873 K, the TiO2 in the 1 at% Rh/TiO2 powders was mainly present as the anatase form. In contrast, at calcination temperatures of 973 K, most of the TiO2 existed in the rutile structure. At a given calcination temperature, increasing the doping amounts of Rh decreases the anatase content and cell volume but increases the crystal size. Compared with pure TiO2 powders synthesised under the same conditions, the temperature for the phase transition of TiO2 from the anatase structure to the rutile structure was lower by 146.8 K in the Rh/TiO2 powders; however, the excitation wavelength of the Rh/TiO2 powders was broadened to the visible light region. Unfortunately, the particles of the Rh/TiO2 powders aggregated resulting in reduced Brunauer–Emmett–Teller surface area, and a decrease in the photocatalytic activity.

[Management strategy and technology of medical assistance to advanced schistosomiasis patients in Hunan Province]

The medical assistance to advanced schistosomiasis patients established by the Chinese government is a major public facility for patients with advanced schistosomiasis. Since the medical assistance to advance schistosomiasis patients in Hunan Province started ten years ago, a set of mature and operable programs with whole program management and related technologies has been developed. The author investigated the data on medical assistance to advanced schistosomiasis patients in Hunan Province during the last 10 years (from 2006 to 2015) retrospectively, and found that the program had high therapeutic effect and high satisfaction degree of both patients and the society. In order to improve the management of the medical assistance to advanced schistosomiasis patients and share our experiences of the whole program management and related technologies with the colleagues of other provinces, this paper mainly illustrates the experiences of the program, as well as the existing problems and related strategies.

[Diagnosis and treatment of imported African schistosomiasis]

This paper summarizes the clinical diagnosis and treatment of imported African schistosomiasis, in order to make the therapeutic standards. Imported African schistosomiasis includes mainly schistosomiasis haematobia and schistosomiasis mansoni in China. In order to set up the operational standards, enhance diagnostic and cure rates, and reduce the complications, we review the related literature combined with our experience over years, and summarize, in this paper, the pathogenic mechanism, and key points of clinical diagnosis and treatment of schistosomiasis haematobia and schistosomiasis mansoni, so as to provide the reference for clinical doctors.

Anisotropic magnetoresistance in an antiferromagnetic semiconductor

Recent studies in devices comprising metal antiferromagnets have demonstrated the feasibility of a novel spintronic concept in which spin-dependent phenomena are governed by an antiferromagnet instead of a ferromagnet. Here we report experimental observation of the anisotropic magnetoresistance in an antiferromagnetic semiconductor Sr2IrO4. Based on ab initio calculations, we associate the origin of the phenomenon with large anisotropies in the relativistic electronic structure. The antiferromagnet film is exchange coupled to a ferromagnet, which allows us to reorient the antiferromagnet spin-axis in applied magnetic fields via the exchange spring effect. We demonstrate that the semiconducting nature of our AFM electrode allows us to perform anisotropic magnetoresistance measurements in the current-perpendicular-to-plane geometry without introducing a tunnel barrier into the stack. Temperature-dependent measurements of the resistance and anisotropic magnetoresistance highlight the large, entangled tunabilities of the ordinary charge and spin-dependent transport in a spintronic device utilizing the antiferromagnet semiconductor.

Induced magnetization in La0.7Sr0.3MnO3/BiFeO3 superlattices

Using polarized neutron reflectometry, we observe an induced magnetization of 75 ± 25 kA/m at 10 K in a La(0.7)Sr(0.3)MnO(3) (LSMO)/BiFeO(3) superlattice extending from the interface through several atomic layers of the BiFeO(3) (BFO). The induced magnetization in BFO is explained by density functional theory, where the size of band gap of BFO plays an important role. Considering a classical exchange field between the LSMO and BFO layers, we further show that magnetization is expected to extend throughout the BFO, which provides a theoretical explanation for the results of the neutron scattering experiment.

Room-temperature antiferromagnetic memory resistor

The bistability of ordered spin states in ferromagnets provides the basis for magnetic memory functionality. The latest generation of magnetic random access memories rely on an efficient approach in which magnetic fields are replaced by electrical means for writing and reading the information in ferromagnets. This concept may eventually reduce the sensitivity of ferromagnets to magnetic field perturbations to being a weakness for data retention and the ferromagnetic stray fields to an obstacle for high-density memory integration. Here we report a room-temperature bistable antiferromagnetic (AFM) memory that produces negligible stray fields and is insensitive to strong magnetic fields. We use a resistor made of a FeRh AFM, which orders ferromagnetically roughly 100 K above room temperature, and therefore allows us to set different collective directions for the Fe moments by applied magnetic field. On cooling to room temperature, AFM order sets in with the direction of the AFM moments predetermined by the field and moment direction in the high-temperature ferromagnetic state. For electrical reading, we use an AFM analogue of the anisotropic magnetoresistance. Our microscopic theory modelling confirms that this archetypical spintronic effect, discovered more than 150 years ago in ferromagnets, is also present in AFMs. Our work demonstrates the feasibility of fabricating room-temperature spintronic memories with AFMs, which in turn expands the base of available magnetic materials for devices with properties that cannot be achieved with ferromagnets.

Full electric control of exchange bias

We report the creation of a multiferroic field effect device with a BiFeO(3) (BFO) (antiferromagnetic-ferroelectric) gate dielectric and a La(0.7)Sr(0.3)MnO(3) (LSMO) (ferromagnetic) conducting channel that exhibits direct, bipolar electrical control of exchange bias. We show that exchange bias is reversibly switched between two stable states with opposite exchange bias polarities upon ferroelectric poling of the BFO. No field cooling, temperature cycling, or additional applied magnetic or electric field beyond the initial BFO polarization is needed for this bipolar modulation effect. Based on these results and the current understanding of exchange bias, we propose a model to explain the control of exchange bias. In this model the coupled antiferromagnetic-ferroelectric order in BFO along with the modulation of interfacial exchange interactions due to ionic displacement of Fe(3+) in BFO relative to Mn(3+/4+) in LSMO cause bipolar modulation.

Interface control of bulk ferroelectric polarization

The control of material interfaces at the atomic level has led to novel interfacial properties and functionalities. In particular, the study of polar discontinuities at interfaces between complex oxides lies at the frontier of modern condensed matter research. Here we employ a combination of experimental measurements and theoretical calculations to demonstrate the control of a bulk property, namely ferroelectric polarization, of a heteroepitaxial bilayer by precise atomic-scale interface engineering. More specifically, the control is achieved by exploiting the interfacial valence mismatch to influence the electrostatic potential step across the interface, which manifests itself as the biased-voltage in ferroelectric hysteresis loops and determines the ferroelectric state. A broad study of diverse systems comprising different ferroelectrics and conducting perovskite underlayers extends the generality of this phenomenon.

Microscopic origin of the giant ferroelectric polarization in tetragonal-like BiFeO(3)

We report direct experimental evidence for a room-temperature, ∼130  μC/cm(2) ferroelectric polarization from the tetragonal-like BiFeO(3) phase. The physical origin of this remarkable enhancement of ferroelectric polarization has been investigated by a combination of x-ray absorption spectroscopy, scanning transmission electron microscopy, and first principles calculations. A large strain-induced Fe-ion displacement relative to the oxygen octahedra, combined with the contribution of Bi 6s lone pair electrons, is the mechanism driving the large ferroelectric polarization in this tetragonal-like phase.

Looking beyond the obvious: IgA nephropathy in a liver transplant recipient

Seventeen years after a liver transplant for biliary atresia, an adolescent presented with renal failure. The serum level of cyclosporine was sub-therapeutic; and, in spite of dosage adjustments, the patient’s status did not improve. Given the patient’s age, future renal transplant was a feasible consideration. However, this warranted investigation in the form of a renal biopsy in an attempt to confirm the underlying cause(s) of her renal failure. The renal biopsy revealed marked alteration in the renal anatomy due to IgA deposition, interstitial fibrosis, and hyaline arteriopathy.

The Effects of Open Lung Ventilation on Respiratory Mechanics and Haemodynamics in Atelectatic Infants after Cardiopulmonary Bypass

Acute lung injury (ALI) frequently occurs in infants after cardiopulmonary bypass (CPB) surgery and it sometimes develops into acute respiratory distress syndrome in critically ill infants, which can be life threatening. This study investigated the effects of open lung ventilation on the haemodynamics and respiratory mechanics of 64 infants (34 males; 30 females) with a mean ± SD age of 8.3 ± 0.3 months who developed ALI following CPB surgery. Open lung ventilation significantly improved the respiratory mechanics and oxygenation parameters of the infants, including the partial pressure of oxygen in arterial blood (PaO2), the ratio of PaO2/FiO2 (fraction of inspired oxygen), peak inspiratory pressure, static compliance and airway resistance. It is concluded that open lung ventilation can greatly improve oxygenation and respiratory mechanics in infants with ALI following CPB surgery.

An experimental investigation of analog delay generation for dynamic control of microsensors and atomic force microscopy

We present an implementation of pure-time-delay generation in analog signals located in the kilo-Hertz frequency band. The controlled constant delays that are produced engage in a feedback system to investigate the dynamic response of microcantilevers. Delayed systems offer a vast richness of eigenvalues resulting in the possibility of excitations at frequencies other than that of the fundamental mode. Different cantilever actuation and delay generation approaches are investigated and compared, and detailed experimental observation of the dynamic response of the system is presented. Based on our results, an acoustic excitation is devised that may be used as an efficient sensor.

Skin colonization by Staphylococcus aureus in patients with eczema and atopic dermatitis and relevant combined topical therapy: a double-blind multicentre randomized controlled trial

BACKGROUND

Staphylococcus aureus has a peculiar ability to colonize the skin of patients with eczema and atopic dermatitis (AD), and is consistently found in eczematous skin lesions in these patients. A correlation between the severity of the eczema and colonization with S. aureus has been demonstrated, and it has been determined that bacterial colonization is an important factor aggravating skin lesions. Patients colonized with S. aureus have been treated with antibiotics in several open and double-blind placebo-controlled studies, with conflicting results.

OBJECTIVES

To investigate the colonizing features of S. aureus in the lesional and nonlesional skin of patients with eczema and AD in China and to compare the therapeutic effect of mupirocin plus hydrocortisone butyrate with vehicle ointment plus hydrocortisone butyrate.

METHODS

A multicentre, double-blind randomized trial was conducted. Eczema Area and Severity Index (EASI) scores were evaluated before the start of the trial and on the 7th, 14th and 28th day of treatment. Swabs for bacterial isolation were taken from lesional skin before the start of the trial and on the 7th, 14th and 28th day of treatment, and from nonlesional skin only before the start of the trial. A combination topical therapy with mupirocin plus hydrocortisone butyrate ointment was used in the experimental group, with vehicle ointment plus hydrocortisone butyrate ointment as a control.

RESULTS

Of 327 patients enrolled in the study, 208 had eczema and 119 had AD. Bacteria were isolated from 70.2% of lesional and 32.7% of nonlesional skin samples from patients with eczema, of which S. aureus accounted for 47.3% and 27.9%, respectively. Bacteria were isolated from 74.8% of lesional and 34.5% of nonlesional skin samples from patients with AD, of which S. aureus accounted for 79.8% and 80.5%, respectively. The colonization density of S. aureus was markedly higher in lesional than in nonlesional skin, both in patients with eczema and with AD (P < 0.01, P < 0.05), and was positively correlated with lesion severity. Considering the EASI scores before and after treatment and the final effective rate, good therapeutic effects were obtained in both the combination experimental groups and the control groups (P < 0.01), and there were no differences in the global therapeutic effect between the two groups in patients with eczema and with AD (P > 0.05). However, in patients with eczema with a clinical score of > 8 or in patients with AD with a clinical score of > 7, the therapeutic effect in the experimental groups was superior to that in the control groups (P < 0.05) on the 7th day of treatment. There were no differences between the two groups on the 14th and 28th days of treatment (P > 0.05). Following the improvement of symptoms and signs of eczema and AD, the positive rates of bacteria and S. aureus were reduced on the 7th day of treatment.

CONCLUSIONS

This study confirmed that lesional skin of patients with eczema and AD was more frequently colonized with S. aureus than was nonlesional skin. The more severe the eczema, the higher the colonization rate of S. aureus, and S. aureus was also more often present in lesional and nonlesional skin in patients with AD than in those with eczema. Staphylococcus aureus infection is related to the pathogenesis of eczema and AD. An antibiotic-corticosteroid combination and corticosteroid alone both gave good therapeutic effect in eczema and in AD, and both reduced colonization by S. aureus. Early combined topical therapy is beneficial to patients with moderate to severe eczema and AD, and it is unnecessary to use antibiotics at later stages of disease or in mild eczema or AD.

Adsorption of trinitrotoluene on uncoated silicon microcantilever surfaces

We measured the adsorption characteristics of trinitrotoluene (TNT) on piezoresistive silicon microcantilever surfaces under ambient air using a well-characterized TNT vapor generator. This allowed us to quantify the adsorption parameters and to estimate the sticking coefficient. The sticking coefficient initially increases with TNT exposure time and then levels off around 0.3. Atomic force microscopy images of silicon surfaces exposed to TNT revealed "island" formation of the adsorbate on the silicon surface. At low exposure times, mainly the number density of islands increased with exposure time; at longer exposure times, the size (in particular, height) of the islands grew, corresponding to the higher sticking coefficients. These observations can be qualitatively explained via the difference between TNT-surface and TNT-TNT interactions mediated by water molecules.

Dalitz plot analysis of the decay D(+)-->K(-)pi(+)pi(+) and indication of a low-mass scalar Kpi resonance

We study the Dalitz plot of the decay D(+)-->K(-)pi(+)pi(+) with a sample of 15090 events from Fermilab experiment E791. Modeling the decay amplitude as the coherent sum of known Kpi resonances and a uniform nonresonant term, we do not obtain an acceptable fit. If we allow the mass and width of the K(*)(0)(1430) to float, we obtain values consistent with those from PDG but the chi(2) per degree of freedom of the fit is still unsatisfactory. A good fit is found when we allow for the presence of an additional scalar resonance, with mass 797+/-19+/-43 MeV/c(2) and width 410+/-43+/-87 MeV/c(2). The mass and width of the K(*)(0)(1430) become 1459+/-7+/-5 MeV/c(2) and 175+/-12+/-12 MeV/c(2), respectively. Our results provide new information on the scalar sector in hadron spectroscopy.

Observation of color-transparency in diffractive dissociation of pions

We have studied the diffractive dissociation into dijets of 500 GeV/c pions scattering coherently from carbon and platinum targets. Extrapolating to asymptotically high energies (where t(min)-->0), we find that when the per-nucleus cross section for this process is parametrized as sigma = sigma0Aalpha, alpha has values near 1.6, the exact result depending on jet transverse momentum. These values are in agreement with those predicted by theoretical calculations of color-transparency.

Direct measurement of the pion valence-quark momentum distribution, the pion light-cone wave function squared

We present the first direct measurements of the pion valence-quark momentum distribution which is related to the square of the pion light-cone wave function. The measurements were carried out using data on diffractive dissociation of 500 GeV/c pi(-) into dijets from a platinum target at Fermilab experiment E791. The results show that the /q&q> light-cone asymptotic wave function describes the data well for Q2 approximately 10 (GeV/c)(2) or more. We also measured the transverse momentum distribution of the diffractive dijets.

Search for rare and forbidden Charm Meson decays D0 --> Vl+l- and hhll

We report results of a search for flavor-changing neutral current (FCNC), lepton flavor, and lepton-number violating decays of the D0 (and its antiparticle) into three and four bodies. Using data from Fermilab charm hadroproduction experiment E791, we examine modes with two leptons (muons or electrons) and a rho(0), K( *0), or straight phi vector meson or a nonresonant pi(pi), Kpi, or KK pair of pseudoscalar mesons. No evidence for any of these decays is found. Therefore, we present branching-fraction upper limits at 90% confidence level for the 27 decay modes examined (18 new).

Study of the D(+)(s)-->pi(-)pi(+)pi(+) decay and measurement of f(0) masses and widths

From a sample of 848+/-44 D(+)(s)-->pi(-)pi(+)pi(+) decays, we find gamma(D(+)(s)-->pi(-)pi(+)pi(+))/gamma(D(+)(s)-->straight phipi(+)) = 0.245+/-0.028(+0.019)(-0.012). Using a Dalitz plot analysis of this three body decay, we find significant contributions from the channels rho(0)(770)pi(+), rho(0)(1450)pi(+), f(0)(980)pi(+), f(2)(1270)pi(+), and f(0)(1370)pi(+). We also present the values obtained for masses and widths of the resonances f(0)(980) and f(0)(1370).

Experimental evidence for a light and broad scalar resonance in D(+) --> pi(-)pi(+)pi(+) decay

From a sample of 1172 +/- 61 D(+)-->pi(-)pi(+)pi(+) decays, we find gamma(D(+)-->pi(-)pi(+)pi(+))/gamma(D(+)-->K-pi(+)pi(+)) = 0.0311 +/- 0.0018(+0.0016)(-0.0026). Using a coherent amplitude analysis to fit the Dalitz plot of these decays, we find strong evidence that a scalar resonance of mass 478(+24)(-23) +/- 17 MeV/c(2) and width 324(+42)(-40) +/- 21 MeV/c(2) accounts for approximately half of all decays.

Quantification of 3-nitrotyrosine in biological tissues and fluids: generating valid results by eliminating artifactual formation

Reactive nitrogen species such as peroxynitrite can nitrate specific amino acids, whether free or protein bound, and 3-nitrotyrosine is believed to be one marker of this reaction. To examine the significance of this pathway in biological systems we have developed an accurate, sensitive, and specific assay for 3-nitrotyrosine based on combined liquid chromatography tandem mass spectrometry. Our approach allowed simultaneous analysis of both tyrosine and 3-nitrotyrosine and employs isotopomer standards (i.e., [15N1, 13C9]-tyrosine and [13C6]-3nitrotyrosine). Calibration curves were linear (r2 = 0.999) across the range 0.5-100 pg/microL (i.e., 2.2-442 fmol/microL), and the detection limit for standard samples was 0.5 pg/microL (2.2 fmol/microL, or 10 fmol on column; S/N = 5) or 1 pg/microL (4.4 fmol/microL) for extracted (biological) samples. As a component of this study we have undertaken an extensive investigation of artifactual formation of 3-nitrotyrosine under conditions that exist during sample extraction and derivatization. Our studies show that under appropriate conditions (low pH, elevated temperatures, and in the presence of a vast excess of the two substrates, tyrosine and the nitrate anion), 3-nitrotyrosine can readily be formed as an artifact.

Trifluoroacetic anhydride-catalyzed nitration of toluene as an approach to the specific analysis of nitrate by gas chromatography-mass spectrometry

The nitration of aromatic compounds by electrophilic substitution is often utilized in analyses of nitrate concentrations in physiological samples by gas chromatographic methods. Problems associated with the use of concentrated sulfuric acid, which is normally used to catalyze this reaction, led us to investigate an alternative method. We describe here a facile GC/MS assay for nitrate in plasma or urine samples which takes advantage of the ability of trifluoroacetic anhydride (TFAA) to catalyze the nitration of aromatics. Toluene, utilized as both reaction solvent and electrophile, was shown to react with nitrate in the presence of TFAA to quantitatively produce the three nitrotoluene isomers (ratio o-:m:p-, approx 57:3:40). Following the incorporation of 15N-labeled nitrate as internal standard, nitrotoluene was quantified using GC/MS by analysis of the selected the ion pairs m/z 120 and 121 (M+ -OH) for the o-isomer or m/z 137 and 138 (molecular ion, M+) for the p-isomer. The limit of detection for nitrate after TFAA-catalyzed conversion to nitrotoluene was less than 100 fmol on column (s/n; 40:1). The TFAA-based GC/MS assay was compared with that utilizing the usual catalyst, concentrated sulfuric acid. With the exception of samples containing nitroarginine analogues, good correlation was found for urine or plasma samples analyzed using either a standard sulfuric acid-catalyzed method or the TFAA-catalyzed procedure. Nitroarginine analogues, which can be present in samples following their use as nitric oxide synthase inhibitors, did not decompose under the conditions of the TFAA-catalyzed assay and, hence, do not give rise to significant interference with nitrate analysis in this procedure. In contrast, catalytic sulfuric acid caused nitroarginine analogues to decompose (essentially quantitatively) and cause spuriously high nitrate levels in samples. The use of TFAA as a catalyst for the nitration of toluene enables a facile and sensitive GC/MS analysis for nitrate which offers improved safety and sample integrity.