Tyrosine nitration site specificity identified by LC/MS innitrite-modified collagen type IV

Zhen Wang,David C. Paik,James P. Dillon,Elizabeth R. Gaillard 생화학분자생물학회 2007 Experimental and molecular medicine Vol.39 No.1

Non-enzymatic nitrite induced collagen cross-link-ing results in changes reminiscent of age-related damage and parallels the well-known model system, non-enzymatic glycation. We have recently ob-served that nitrite modification of basement mem-brane proteins can induce deleterious effects on overlying retinal pigment epithelial cells in studies relevant to age-related macular degeneration. The 3-nitro-tyrosine (3-NT) as a product of the reaction and to identify the site specificity of nitration in collagen IV, a major component of basement mem-branes. Human collagen type IV was modified via incubation with 200 mM NaNO2 (pH = 7.38) for one week at 37oC. The modified protein was prepared in 2 different ways, including acid hydrolysis and trypsin digestion for site specificity determination. The samples were analyzed by LC/MS using a C12 RP column. Site specificity was determined from tan-dem MS/MS data utilizing TurboSEQUEST software and the Swiss-Prot sequence database. 3-NT was detected in protein digests and acid hydrolysates of nitrite modified collagen IV. Positive identification with standard 3-NT was confirmed by identical Rt, λmax= 279 nm and 355 nm, and m/z= 227. Analyses of tryptic digests identified four sites of tyrosine ni-tration, α1(IV)Y348, α1(IV)Y534, α2(IV)Y327, and α2(IV)-Y1081. These sites are located in the triple- helical region of the protein and provide clues regarding potential sites for nitrite modification in collagen type IV.

Tracking heavy water (D₂O) incorporation for identifying and sorting active microbial cells

Berry, David,Mader, Esther,Lee, Tae Kwon,Woebken, Dagmar,Wang, Yun,Zhu, Di,Palatinszky, Marton,Schintlmeister, Arno,Schmid, Markus C.,Hanson, Buck T.,Shterzer, Naama,Mizrahi, Itzhak,Rauch, Isabella,De National Academy of Sciences 2015 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.112 No.2

<P><B>Significance</B></P><P>Measuring activity patterns of microbes in their natural environment is essential for understanding ecosystems and the multifaceted interactions of microorganisms with eukaryotes. In this study, we developed a technique that allows fast and nondestructive activity measurements of microbial communities on a single-cell level. Microbial communities were amended with heavy water (D<SUB>2</SUB>O), a treatment that does not change the available substrate pool. After incubation, physiologically active cells are rapidly identified with Raman microspectroscopy by measuring cellular D incorporation. Using this approach, we characterized the activity patterns of two dominant microbes in mouse cecum samples amended with different carbohydrates and discovered previously unidentified bacteria stimulated by mucin and/or glucosamine by combining Raman microspectroscopy and optical tweezer-based sorting.</P><P>Microbial communities are essential to the function of virtually all ecosystems and eukaryotes, including humans. However, it is still a major challenge to identify microbial cells active under natural conditions in complex systems. In this study, we developed a new method to identify and sort active microbes on the single-cell level in complex samples using stable isotope probing with heavy water (D<SUB>2</SUB>O) combined with Raman microspectroscopy. Incorporation of D<SUB>2</SUB>O-derived D into the biomass of autotrophic and heterotrophic bacteria and archaea could be unambiguously detected via C-D signature peaks in single-cell Raman spectra, and the obtained labeling pattern was confirmed by nanoscale-resolution secondary ion MS. In fast-growing <I>Escherichia coli</I> cells, label detection was already possible after 20 min. For functional analyses of microbial communities, the detection of D incorporation from D<SUB>2</SUB>O in individual microbial cells via Raman microspectroscopy can be directly combined with FISH for the identification of active microbes. Applying this approach to mouse cecal microbiota revealed that the host-compound foragers <I>Akkermansia muciniphila</I> and <I>Bacteroides acidifaciens</I> exhibited distinctive response patterns to amendments of mucin and sugars. By Raman-based cell sorting of active (deuterated) cells with optical tweezers and subsequent multiple displacement amplification and DNA sequencing, novel cecal microbes stimulated by mucin and/or glucosamine were identified, demonstrating the potential of the nondestructive D<SUB>2</SUB>O-Raman approach for targeted sorting of microbial cells with defined functional properties for single-cell genomics.</P>

Development and validation of a numerical model for steel roof cladding subject to static uplift loads

Amy C. Lovisa,Vincent Z. Wang,David J. Henderson,John D. Ginger 한국풍공학회 2013 Wind and Structures, An International Journal (WAS Vol.17 No.5

Thin, high-strength steel roof cladding is widely used in residential and industrial low-rise buildings and is susceptible to failure during severe wind storms such as cyclones. Current cladding design is heavily reliant on experimental testing for the determination of roof cladding performance. Further study is necessary to evolve current design standards, and numerical modelling of roof cladding can provide an efficient and cost effective means of studying the response of cladding in great detail. This paper details the development of a numerical model that can simulate the static response of corrugated roof cladding. Finite element analysis (FEA) was utilised to determine the response of corrugated cladding subject to a static wind pressure, which included the anisotropic material properties and strain-hardening characteristics of the thin steel roof cladding. The model was then validated by comparing the numerical data with corresponding experimental test results. Based on this comparison, the model was found to successfully predict the fastener reaction, deflection and the characteristics in deformed shape of the cladding. The validated numerical model was then used to predict the response of the cladding subject to a design cyclone pressure trace, excluding fatigue effects, to demonstrate the potential of the model to investigate more complicated loading circumstances.

Optimisation of Readout Performance of Phase-Change Probe Memory in Terms of Capping Layer and Probe Tip

Lei Wang,C. David Wright,Mustafa. M. Aziz,Ci Hui Yang,Guo Wei Yang 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.6

The capping layer and the probe tip that serve as the protective layer and the recording tool, respectively, for phase-change probe memory play an important role on the writing performance of phase-change probe memory, thus receiving considerable attention. On the other hand, their influence on the readout performance of phasechange probe memory has rarely been reported before. A three-dimensional parametric study based on the Laplace equation was therefore conducted to investigate the effect of the capping layer and the probe tip on the resulting reading contrast for the two cases of reading a crystalline bit from an amorphous matrix and reading an amorphous bit from a crystalline matrix. The results indicated that a capping layer with a thickness of 2 nm and an electrical conductivity of 50 Ω−1m−1 is able to provide an appropriate reading contrast for both the cases, while satisfying the previous writing requirement, particularly with the assistance of a platinum silicide probe tip.

Development and validation of a numerical model for steel roof cladding subject to static uplift loads

Lovisa, Amy C.,Wang, Vincent Z.,Henderson, David J.,Ginger, John D. Techno-Press 2013 Wind and Structures, An International Journal (WAS Vol.17 No.5

Thin, high-strength steel roof cladding is widely used in residential and industrial low-rise buildings and is susceptible to failure during severe wind storms such as cyclones. Current cladding design is heavily reliant on experimental testing for the determination of roof cladding performance. Further study is necessary to evolve current design standards, and numerical modelling of roof cladding can provide an efficient and cost effective means of studying the response of cladding in great detail. This paper details the development of a numerical model that can simulate the static response of corrugated roof cladding. Finite element analysis (FEA) was utilised to determine the response of corrugated cladding subject to a static wind pressure, which included the anisotropic material properties and strain-hardening characteristics of the thin steel roof cladding. The model was then validated by comparing the numerical data with corresponding experimental test results. Based on this comparison, the model was found to successfully predict the fastener reaction, deflection and the characteristics in deformed shape of the cladding. The validated numerical model was then used to predict the response of the cladding subject to a design cyclone pressure trace, excluding fatigue effects, to demonstrate the potential of the model to investigate more complicated loading circumstances.

Low Molecular Weight Protamine/ Insulin Formulation with Potential to Attenuate Protamine-Masqueraded Insulin Allergy

Huining He,Victor C. Yang,Allan E. David,Jian Zhang,박윤신,Jianxin Wang,Yongzhuo Huang,Jingkang Wang 한국고분자학회 2011 Macromolecular Research Vol.19 No.12

<i>In operando</i> X-ray diffraction strain measurement in Ni₃Sn₂ – Coated inverse opal nanoscaffold anodes for Li-ion batteries

Glazer, Matthew P.B.,Wang, Junjie,Cho, Jiung,Almer, Jonathan D.,Okasinski, John S.,Braun, Paul V.,Dunand, David C. Elsevier 2017 Journal of Power Sources Vol.367 No.-

<P><B>Abstract</B></P> <P>Volume changes associated with the (de)lithiation of a nanostructured Ni<SUB>3</SUB>Sn<SUB>2</SUB> coated nickel inverse opal scaffold anode create mismatch stresses and strains between the Ni<SUB>3</SUB>Sn<SUB>2</SUB> anode material and its mechanically supporting Ni scaffold. Using <I>in operando</I> synchrotron x-ray diffraction measurements, elastic strains in the Ni scaffold are determined during cyclic (dis)charging of the Ni<SUB>3</SUB>Sn<SUB>2</SUB> anode. These strains are characterized using both the center position of the Ni diffraction peaks, to quantify the average strain, and the peak breadth, which describes the distribution of strain in the measured volume. Upon lithiation (half-cell discharging) or delithiation (half-cell charging), compressive strains and peak breadth linearly increase or decrease, respectively, with charge. The evolution of the average strains and peak breadths suggests that some irreversible plastic deformation and/or delamination occurs during cycling, which can result in capacity fade in the anode. The strain behavior associated with cycling of the Ni<SUB>3</SUB>Sn<SUB>2</SUB> anode is similar to that observed in recent studies on a Ni inverse-opal supported amorphous Si anode and demonstrates that the (de)lithiation-induced deformation and damage mechanisms are likely equivalent in both anodes, even though the magnitude of mismatch strain in the Ni<SUB>3</SUB>Sn<SUB>2</SUB> is lower due to the lower (de)lithiation-induced contraction/expansion.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Lithiation-induced strains quantified in a Ni<SUB>3</SUB>Sn<SUB>2</SUB> inverse opal anode <I>in operando</I>. </LI> <LI> Lithiation induces compressive average strains in Ni inverse opal scaffold. </LI> <LI> Ni inverse opal scaffold strain distribution reversibly broadens upon lithiation. </LI> <LI> Three measured volumes show similar cyclic strain averages and distributions. </LI> <LI> Ni<SUB>3</SUB>Sn<SUB>2</SUB> measured cyclic strains are similar to prior Si inverse opal anode studies. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Comparison of sequential versus concurrent chemoradiation regimens in non-metastatic muscle-invasive bladder cancer

Heidi M. Vieira,David P. Kasper,Runqiu Wang,Lynette M. Smith,Charles A. Enke,Raymond C. Bergan,Benjamin A. Teply,Michael J. Baine 대한방사선종양학회 2023 Radiation Oncology Journal Vol.41 No.3

Purpose: The treatment approach for non-metastatic bladder cancer is guided by an invasion of the muscular layer of the bladder wall. Radical cystectomy is the recommended treatment for muscle-invasive disease. However, it has considerable morbidity and mortality and is not suited for many patients. Trimodality therapy consisting of chemoradiation after transurethral resection of bladder tumor offers a definitive approach with bladder-sparing potential. However, there is a lack of research defining the optimal combination of chemotherapy and radiation in this setting. Materials and Methods: We extracted patient data from the National Cancer Database to compare survival outcomes and demographic factors in 2,227 non-metastatic bladder cancer patients who were treated with chemotherapy sequential to or concurrently with radiation. Sequential treatment was defined as chemotherapy beginning >14 days before radiation, and concurrent was defined as beginning within 14 days of the first radiation. Results: The sequential treatment group patients were younger (mean age, 74 vs. 78 years; p < 0.001) with more advanced disease. We found no difference in overall survival between patients who received chemotherapy sequential to radiation and those who received concurrent chemoradiation only (p = 0.533). Conclusion: Our data are concordant with a previous prospective study, and support that chemotherapy prior to radiation does not decrease survival outcomes relative to patients receiving only concurrent chemoradiation. Given that the sequential group had an overall higher stage but no difference in survival, downstaging chemotherapy prior to radiation may be helpful in these patients. Further studies including a larger, multi-institutional clinical trial are indicated to support clinical decision-making.

Does Acupuncture Therapy Alter Activation of Neural Pathway for Pain Perception in Irritable Bowel Syndrome?: A Comparative Study of True and Sham Acupuncture Using Functional Magnetic Resonance Imaging

( Winnie Cw Chu ),( Justin Cy Wu ),( David Tw Yew ),( Liang Zhang ),( Lin Shi ),( David Kw Yeung ),( De Feng Wang ),( Raymond Ky Tong ),( Ya Wen Chan ),( Li Xing Lao ),( Ping C Leung ),( Brian M Berma 대한소화기기능성질환·운동학회 2012 Journal of Neurogastroenterology and Motility (JNM Vol.18 No.3

Background/Aims Patients with irritable bowel syndrome (IBS) are characterized by abnormal central processing with altered brain activation in response to visceral nociceptive signals. The effect of electroacupuncture (EA) on IBS patients is unclear. The study is set to study the effect of EA on brain activation during noxious rectal distension in IBS patients using a randomized sham-controlled model. Methods Thirty IBS-diarrhea patients were randomized to true electroacupuncture or sham acupuncture. Functional MRI was performed to evaluate cerebral activation at the following time points: (1) baseline when there was rectal distension only, (2) rectal distension during application of EA, (3) rectal distension after cessation of EA and (4) EA alone with no rectal distension. Group comparison was made under each condition using SPM5 program. Results Rectal distension induced significant activation of the anterior cingulated cortex, prefrontal cortex, thalamus, temporal regions and cerebellum at baseline. During and immediately after EA, increased cerebral activation from baseline was observed in the anterior cingulated cortex, bilateral prefrontal cortex, thalamus, temporal regions and right insula in both groups. However, true electroacupuncture led to significantly higher activation at right insula, as well as pulvinar and medial nucleus of the thalamus when compared to sham acupuncture. Conclusions We postulate that acupuncture might have the potential effect of pain modulation in IBS by 2 actions: (1) modulation of serotonin pathway at insula and (2) modulation of mood and affection in higher cortical center via ascending pathway at the pulvinar and medial nucleus of the thalamus. (J Neurogastroenterol Motil 2012;18:305-316)

Strawberry Consumption Is Associated with Increased Antioxidant Capacity in Serum

Susanne M. Henning,Navindra P. Seeram,Yanjun Zhang,,Kun Gao,Ru-Po Lee,David C. Wang,Alona Zerlin,Hannah Karp,Gail Thames,Jenny Kotlerman,Zhaoping Li,David Heber 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.1

Strawberries are known to contain antioxidants, but the significance of ingesting antioxidant-rich fruits remains to be established. In order to determine whether the consumption of strawberries impacted measures of in vivo antioxidant capacity, frozen strawberries (250g) were administered daily for 3 weeks to 21 healthy female volunteers. Compliance was confirmed by quantitating pelargonidin-glucuronide, urolithin A-glucuronide, and 2,5-dimethyl-4-hydroxy-3-[2H]furanone-glucuronide in plasma and urine by liquid chromatography–mass spectrometry and antioxidant capacity in serum measured by the increase in lag phase of low-density lipoprotein after copper sulfate exposure, DNA strand breaks in lymphocytes, and activity of phase II enzymes. Among these measures lipid peroxidation lag time increased by 20% (P<.01), whereas other measures did not change significantly. The potent antioxidant defenses in humans make determination of changes due to dietary ingestion in healthy individuals difficult. In summary, daily consumption of strawberries resulted in a modest but significant increase in antioxidant capacity in a healthy population.