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Goodman KJ, Wu JS, Frerichs RR. Compliance with childhood immunizations in Kern County, California. ACTA ACUST UNITED AC 2006; 2:213-22. [PMID: 16228742 DOI: 10.1023/a:1009592329980] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A rapid survey was conducted to describe the immunization status of the 0- to 2-year-old population in selected communities of Kern County, California, and identify reasons for noncompliance with immunization recommendations. Households were selected by two-stage cluster sampling. Among 860 children, 38% had received immunizations on schedule, while 44% had not received the recommended doses for their age. Compliance with the immunization schedule worsened dramatically after the first year of life. Among 2 year olds, the proportion that had the recommended number of vaccine doses was 81% for MMR, 82% for polio, 65% for DTP, and 47% for Hib. Parents' main reasons for noncompliance included child's illness, procrastination, and limited access to information and services. The low levels of compliance reflect lack of active follow-up in preventive health care across socioeconomic levels. The results show the importance of aiming immunization messages at parents and physicians of 12- to 18-month-old children. The rapid survey approach offers public health agencies an efficient means of assessing community health problems and targeting programs according to need.
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Starodub D, Doak RB, Schmidt K, Weierstall U, Wu JS, Spence JCH, Howells M, Marcus M, Shapiro D, Barty A, Chapman HN. Damped and thermal motion of laser-aligned hydrated macromolecule beams for diffraction. J Chem Phys 2005; 123:244304. [PMID: 16396534 DOI: 10.1063/1.2137313] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We consider a monodispersed Rayleigh droplet beam of water droplets doped with proteins. An intense infrared laser is used to align these droplets. The arrangement has been proposed for electron- and x-ray-diffraction studies of proteins which are difficult to crystallize. This paper considers the effect of thermal fluctuations on the angular spread of alignment in thermal equilibrium, and relaxation phenomena, particularly the damping of oscillations excited as the molecules enter the field. The possibility of adiabatic alignment is also considered. We find that damping times in a high-pressure gas cell as used in x-ray-diffraction experiments are short compared with the time taken for molecules to traverse the beam and that a suitably shaped field might be used for electron-diffraction experiments in vacuum to provide adiabatic alignment, thus obviating the need for a damping gas cell.
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Remzi FH, Oncel M, Wu JS. Meshless repair of perineal hernia after abdominoperineal resection: case report. Tech Coloproctol 2005; 9:142-4. [PMID: 16007359 DOI: 10.1007/s10151-005-0213-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2003] [Accepted: 02/21/2004] [Indexed: 11/29/2022]
Abstract
Perineal hernia is a rare complication after major pelvic surgery. Placing non-biodegradable mesh across the pelvic inlet is the best method of repair. A 72-year-old man presented with a perineal hernia 8 years after undergoing an abdominoperineal resection because of rectal cancer. During the repair operation, intestinal spillage occurred, making it impossible to place permanent mesh as planned. Instead, we used the bladder to cover the pelvic inlet. The patient recovered well and after 35 months of follow-up, there was no evidence of hernia recurrence. When mesh placement is not feasible, this bladder mobilization technique can replace it.
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Xu YY, Wang XM, Li J, Li JH, Wu JS, Walker JC, Xu ZH, Chong K. Activation of the WUS gene induces ectopic initiation of floral meristems on mature stem surface in Arabidopsis thaliana. PLANT MOLECULAR BIOLOGY 2005; 57:773-84. [PMID: 15952065 DOI: 10.1007/s11103-005-0952-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2004] [Accepted: 01/19/2005] [Indexed: 05/02/2023]
Abstract
A gain-of-function Arabidopsis mutant was identified via activation tagging genetic screening. The mutant exhibited clustered ectopic floral buds on the surface of inflorescence stems. The mutant was designated as sef for stem ectopic flowers. Our detailed studies indicate that the ectopic flower meristems are initiated from the differentiated cortex cells. Inverse PCR and sequence analysis indicated that the enhancer-containing T-DNA from the activation tagging construct, SKI015, was inserted upstream of the previously cloned WUS gene encoding a homeodomain protein. Studies from RT-PCR, RNA in situ hybridization and transgenic plant analysis further confirmed that the phenotypes of sef are caused by the overexpression of WUS. Our results suggest that overexpression of WUS could trigger the cell pluripotence and reestablish a new meristem in cortex. The type of new meristems caused by WUS overexpression was dependent upon the developmental and physiological stages of a plant. With the help of some undefined factors in the reproductive organs the new meristems differentiated into floral buds. In a vegetative growth plant, however, only the new vegetative buds can be initiated upon the overexpression of WUS. These studies provide new insights of WUS on flower development.
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Wu JS, Spence JCH. Reconstruction of complex single-particle images using charge-flipping algorithm. Acta Crystallogr A 2005; 61:194-200. [PMID: 15724069 DOI: 10.1107/s0108767304033525] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2004] [Accepted: 12/16/2004] [Indexed: 11/10/2022] Open
Abstract
An iterative algorithm is developed to retrieve the complex exit-face wavefunction for a two-dimensional projection of a nanoparticle from a measurement of the oversampled modulus of its Fourier transform in reciprocal space. The algorithm does not require the support (boundary) of the object to be known. A loose support for the complex object is gradually found using the Oszlanyi-Suto charge-flipping algorithm, and a compact support is then iteratively developed using a dynamic Gerchberg-Saxton-Fienup algorithm. At the same time, the complex object is reconstructed using this compact support. The algorithm applies to the reconstruction of complex images with any distribution of phase values from 0 to 2pi. Modification of the algorithm by using real-value constraints for a complex object in the charge-flipping algorithm leads to faster reconstruction of the object whose phase value is smaller than pi/2.
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Spence JCH, Schmidt K, Wu JS, Hembree G, Weierstall U, Doak B, Fromme P. Diffraction and imaging from a beam of laser-aligned proteins: resolution limits. Acta Crystallogr A 2005; 61:237-45. [PMID: 15724074 DOI: 10.1107/s0108767305002710] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2004] [Accepted: 01/24/2005] [Indexed: 11/10/2022] Open
Abstract
The effect of the limited alignment of hydrated molecules is considered in a laser-aligned molecular beam, on diffraction patterns taken from the beam. Simulated patterns for a protein beam are inverted using the Fienup-Gerchberg-Saxton phasing algorithm, and the effect of limited alignment on the resolution of the resulting potential maps is studied. For a typical protein molecule (lysozyme) with anisotropic polarizability, it is found that up to 1 kW of continuous-wave near-infrared laser power (depending on dielectric constant), together with cooling to liquid-nitrogen temperatures, may be needed to produce sufficiently accurate alignment for direct observation of the secondary structure of proteins in the reconstructed potential or charge-density map. For a typical virus (TMV), a 50 W continuous-wave laser is adequate for subnanometre resolution at room temperature. The dependence of resolution on laser power, temperature, molecular size, shape and dielectric constant is analyzed.
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Wu JS, Weierstall U, Spence JCH, Koch CT. Iterative phase retrieval without support. OPTICS LETTERS 2004; 29:2737-2739. [PMID: 15605489 DOI: 10.1364/ol.29.002737] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
An iterative phase retrieval method for nonperiodic objects has been developed from the charge-flipping algorithm proposed in crystallography. A combination of the hybrid input-output (HIO) algorithm and the flipping algorithm has greatly improved performance. In this combined algorithm the flipping algorithm serves to find the support (object boundary) dynamically, and the HIO part improves convergence and moves the algorithm out of local minima. It starts with a single intensity measurement in the Fourier domain and does not require a priori knowledge of the support in the image domain. This method is suitable for general image recovery from oversampled diffuse elastic x-ray and electron-diffraction intensities. The relationship between this algorithm and the output-output algorithm is elucidated.
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Pogrebnyakov AV, Redwing JM, Raghavan S, Vaithyanathan V, Schlom DG, Xu SY, Li Q, Tenne DA, Soukiassian A, Xi XX, Johannes MD, Kasinathan D, Pickett WE, Wu JS, Spence JCH. Enhancement of the superconducting transition temperature of MgB2 by a strain-induced bond-stretching mode softening. PHYSICAL REVIEW LETTERS 2004; 93:147006. [PMID: 15524834 DOI: 10.1103/physrevlett.93.147006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2004] [Indexed: 05/24/2023]
Abstract
We report a systematic increase of the superconducting transition temperature T(c) with a biaxial tensile strain in MgB2 films to well beyond the bulk value. The tensile strain increases with the MgB2 film thickness, caused primarily by the coalescence of initially nucleated discrete islands (the Volmer-Weber growth mode.) The T(c) increase was observed in epitaxial films on SiC and sapphire substrates, although the T(c) values were different for the two substrates due to different lattice parameters and thermal expansion coefficients. We identified, by first-principles calculations, the underlying mechanism for the T(c) increase to be the softening of the bond-stretching E(2g) phonon mode, and we confirmed this conclusion by Raman scattering measurements. The result suggests that the E(2g) phonon softening is a possible avenue to achieve even higher T(c) in MgB2-related material systems.
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Wu JS, Chong K, Xu YY, Tan KH. Cloning and characteristics of an allene oxide synthase gene (TaAOS) of winter wheat. ZHI WU SHENG LI YU FEN ZI SHENG WU XUE XUE BAO = JOURNAL OF PLANT PHYSIOLOGY AND MOLECULAR BIOLOGY 2004; 30:413-20. [PMID: 15627690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
Allene oxide synthase (AOS) is the first enzyme in the lipoxygenase pathway which leads to the formation of jasmonic acid (JA). A full length cDNA of TaAOS was cloned in winter wheat (Triticum aestivum L. cv. Jinghua No.3) seedlings. The open reading frame encompassed 1410 bp encoding a polypeptide of 470 amino acids with calculated molecular mass of 51.9 kD. Southern blot analysis suggested there are three copies of the gene in wheat genome. The TaAOS mRNA could be strongly induced by exogenous JA, and the highest level JA was observed after a 10 h induction. In situ RNA hybridization of seedling indicated preferential gene expression in young leaves, especially in the parenchyma cells around the vascular bundles, and the hybridization also showed that exogenous La(3+) could not suppress the expression of TaAOS induced by JA.
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Nessar G, Remzi FH, Wu JS. Evolving technique for continent ileostomy: valveless pouch design. Tech Coloproctol 2004; 8:49-52; discussion 52. [PMID: 15057592 DOI: 10.1007/s10151-004-0053-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2003] [Accepted: 01/25/2004] [Indexed: 12/31/2022]
Abstract
A continent ileostomy, or Kock pouch, is a useful option for patients with inflammatory bowel disease whose only alternative is an end ileostomy. This technique has a high morbidity rate. Nipple valve slippage is the most common complication, causing incontinence or intubation problems. A novel, valveless continent ileostomy technique is described here. A porcine model was used to create the continent ileostomy. Two pouches were created and tested for integrity and continence using lactated Ringer's solution. Pouch pressure and volume were recorded in one pouch. The valveless continent ileostomy was successfully created twice, and both pouches were continent. An intraluminal pressure of 30 mmHg and a volume of 225 ml were measured in one pouch. In this preliminary report of a valveless continent ileostomy, we had promising results. The future of this technique in clinical practice needs to be addressed with further studies.
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Carrozzini B, Cascarano GL, De Caro L, Giacovazzo C, Marchesini S, Chapman H, He H, Howells M, Wu JS, Weierstall U, Spence JCH. Phasing diffuse scattering. Application of the SIR2002 algorithm to the non-crystallographic phase problem. Acta Crystallogr A 2004; 60:331-8. [PMID: 15218213 DOI: 10.1107/s0108767304012395] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2004] [Accepted: 05/20/2004] [Indexed: 11/10/2022] Open
Abstract
A new phasing algorithm has been used to determine the phases of diffuse elastic X-ray scattering from a non-periodic array of gold balls of 50 nm diameter. Two-dimensional real-space images, showing the charge-density distribution of the balls, have been reconstructed at 50 nm resolution from transmission diffraction patterns recorded at 550 eV energy. The reconstructed image fits well with a scanning-electron-microscope (SEM) image of the same sample. The algorithm, which uses only the density modification portion of the SIR2002 program, is compared with the results obtained via the Gerchberg-Saxton-Fienup HiO algorithm. The new algorithm requires no knowledge of the object's boundary and proceeds from low to high resolution. In this way, the relationship between density modification in crystallography and the HiO algorithm used in signal and image processing is elucidated.
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Wu JS, Spence JCH, O'Keeffe M, Groy TL. Application of a modified Oszlányi and Sütoab initiocharge-flipping algorithm to experimental data. Acta Crystallogr A 2004; 60:326-30. [PMID: 15218212 DOI: 10.1107/s0108767304012231] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2004] [Accepted: 05/19/2004] [Indexed: 11/10/2022] Open
Abstract
The structures of two crystals have been solved using a new iterative phasing method. The iterative phasing algorithm is developed from the 'charge-flipping' method proposed by Oszlányi & Süto [Acta Cryst. (2004), A60, 134-141]. Positivity and point-atom constraints are incorporated within this extremely simple and effective algorithm by flipping (sign reversal) of less-positive density values during the iterations. Convergence is reliably achieved and the two structures were solved. This structure solution method does not require information on atomic scattering factors or symmetry. Heavy atoms can be distinguished from light ones by their charge-density values.
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Wu JS, Zhou LF, Gao GJ, Mao Y, Du GH. [Integrating functional magnetic resonance imaging in neuronavigation surgery of brain tumors involving motor cortex]. ZHONGHUA YI XUE ZA ZHI 2004; 84:632-6. [PMID: 15130301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
OBJECTIVE To assess the value of integrating blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) in neuronavigation surgery of brain tumors involving motor cortex. METHODS A total of 58 patients with brain tumors in or directly adjacent to the motor cortex, with 18 lesions located in primary motor area, 18 lesions located in premotor area, 11 lesions located in primary motor sensory area, 9 lesions located in primary sensory area, and 2 lesions located in supplementary motor area respectively, were randomly divided into 2 groups: trial group including 30 cases undergoing BOLD navigation and control group with 28 cases undergoing routine navigation. A prospective random and matched controlled study was carried out to compare the clinical outcome between the two groups. For the patients in the trial group, the motor tasks consisted of simple flexion-extension finger movements and finger-to-thumb touching in a repeating, pre-planned sequence of either hand. A standard 1.5 T MR system had been utilized to localize the cortical motor hand area, using the BOLD contrast technique. The BOLD images were integrated with the routine navigational MR images (T1-weighted three-dimensional fast spoiled gradient recalled sequence), and then co-registered to the neuronavigation system. For the patients in the control group, the navigational MR imaging examinations were carried out only. RESULTS The statistics analysis confirmed a good balance of main variations between the trial and control groups. The percentage of completely resection of tumors was 86.7% in trial group and 60.7% in control group (P < 0.05). The postoperative contralateral extremities muscle strength were 4.3 +/- 1.1 degree for trial group and 2.5 +/- 1.9 degree for the control group (P < 0.01). The motor functional deficit was observed in 23.3% of the cases of trial group and 71.4% of the cases in trial group (P < 0.05). The mean Karnofsky prognosis scale of the trial group was 88 +/- 27, significantly higher than that of the control group (65 +/- 32, P < 0.01). CONCLUSION BOLD functional MR imaging is of great value in surgical planning and intraoperative functional brain mapping of motor cortex individually. To integrate BOLD data with the routine navigational MR images can supply more precise and real-time information about the relationship between lesions and neighboring cortical motor area. It should be used in neuronavigation surgery to increase the ratio of total resection of brain tumors and decrease the risk of postoperative hemiplegia.
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Shen YJ, Pan W, Xu R, Pan X, Wang LC, Wang Z, Cao F, Tan JW, Wu JS, Wu F, Liu YJ. [Construction of combined site-directed random mutation libraries of recombinant human lymphotoxin]. SHENG WU GONG CHENG XUE BAO = CHINESE JOURNAL OF BIOTECHNOLOGY 2004; 20:43-8. [PMID: 16108488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
To construct the combined site-directed random mutation library of recombinant human Lymphotoxin (rhLT) for in vitro molecular evolution study, and to study the structure and function relationship. The random point mutations at the sites of 46,106 and 130 were individually generated by overlap PCR amplification with the random nucleotide primers. The three point mutations were combined and cloned into pMD-18T vector to construct the combined mutation library. DNA sequencing was used to evaluate the diversity and randomness of the mutation sites. The combined mutation library was re-engineered, inserted in prokaryotic expression vector pBV220, transformed and expressed in Escherichia coli strain DH5alpha. The biological activity of some of the mutants was tested in 1929 mouse fibroblast cells. As much as 1.5 x 10(5) clones were obtained, which represents 4.5 times of the complete mutation libraries at 99% confidence. Sequencing 50 clones revealed no obvious bias in the nucleotide and amino acid mutations at the sites. Among the 30 expressed samples underwent for the bioassay, 70% (21 samples) were inactive, 23.3% (7 samples) had lower activity than rhLT, the remaining 6.7% (2 samples) had higher activity than rhLT. The combined site-directed random mutation library of rhLT has been constructed successfully. In combination with phase display, the library is ready for in vitro molecular evolution study.
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Wu JS, Melcer N, Sharp WP, O'Keeffe M, Spence JCH, Yaghi OM. Structural study of new hydrocarbon nano-crystals by energy-filtered electron diffraction. Ultramicroscopy 2004; 98:145-50. [PMID: 15046793 DOI: 10.1016/j.ultramic.2003.08.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2002] [Revised: 04/16/2003] [Indexed: 11/16/2022]
Abstract
A new brittle hydrocarbon has been successfully synthesized in polycrystalline form, and its crystal structure solved by quantitative electron diffraction. By 3D tilting of the nano-crystals, the lattice type and unit cell parameters were determined. (Triclinic, [Formula: see text] A, [Formula: see text] A, [Formula: see text] A, [Formula: see text] degrees, [Formula: see text] degrees, and [Formula: see text] degrees.) Spot diffraction patterns were obtained at -165 degrees C using the Koehler selected-area mode on a LEO 912 TEM fitted with an omega in-column elastic energy filter. The direct methods algorithm was then applied to merged intensities and a trial structure obtained assuming single scattering. This was further refined to obtain good agreement with a small residual of about 10% using multiple scattering calculations. A diagram of the proposed structure is given.
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Wu JS, Spence JCH. Phase extension in crystallography using the iterative Fienup–Gerchberg–Saxton algorithm and Hilbert transforms. Acta Crystallogr A 2003; 59:577-83. [PMID: 14581757 DOI: 10.1107/s0108767303021123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2003] [Accepted: 09/24/2003] [Indexed: 11/11/2022] Open
Abstract
A procedure for phase extension in electron crystallography is proposed based on the iterative Fienup-Gerchberg-Saxton algorithm in combination with the use of discrete Hilbert transforms. This transform is used to provide oversampling in reciprocal space, thus satisfying the Shannon sampling requirement and introducing reflections with fractional indices. When the procedure is combined with the knowledge of a small set of strong phased Bragg reflections from electron-microscope images (or direct methods), the magnitudes of many non-Bragg reflections can be calculated with useful accuracy, thus enhancing the performance of the iterative algorithm for phase extension. The effects of various constraints used in the iterative algorithm are discussed. In this way, it is shown that the iterative algorithm conventionally used for phasing diffuse scattering from non-periodic objects can also be applied to problems in conventional crystallography to find the phases of high-order (resolution) beams from a known set of low-order (resolution) phases.
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Wu JS, Spence JCH. Structure and bonding in alpha-copper phthalocyanine by electron diffraction. Acta Crystallogr A 2003; 59:495-505. [PMID: 12944614 DOI: 10.1107/s0108767303016866] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2003] [Accepted: 07/30/2003] [Indexed: 11/11/2022] Open
Abstract
Energy-filtered quantitative electron diffraction at liquid nitrogen temperature has been used to examine the atomic structure and bonding of metastable alpha-Cu phthalocyanine crystals. Three theoretical methods (kinematic, kinematic with excitation errors and Bloch wave) were employed for the intensity calculations. The Bloch-wave method was found to account for dynamical effects by greatly reducing the residual factor between experimental and simulated results. A new method for calculating electron scattering factors for partially charged ions is proposed and the sensitivity of electron diffraction to charge transfer is discussed. The atomic charge states were analyzed for alpha-Cu phthalocyanine using a charge cloud model in which the Gaussian bond charge is positioned along the bonds. Spot patterns were collected in the Kohler mode at two beam energies to reduce error. Using the best-fitting model, a deformation charge-density map is produced and compared to the neutral-atom model. From this, the main features of atomic charge transfer in the alpha-Cu phthalocyanine structure can be seen in the (010) plane.
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Spence JCH, Wu JS, Giacovazzo C, Carrozzini B, Cascarano GL, Padmore HA. Solving non-periodic structures using direct methods: phasing diffuse scattering. Acta Crystallogr A 2003; 59:255-61. [PMID: 12714777 DOI: 10.1107/s0108767303005233] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2002] [Accepted: 03/04/2003] [Indexed: 11/10/2022] Open
Abstract
The problem of reconstructing the charge density of a non-periodic sample from its diffuse X-ray scattering is considered. For a sample known to be isolated, an artificial superlattice may be assumed and the numerical direct methods of crystallography applied to the continuous distribution of diffuse scattering in order to solve the phase problem. This method is applied to simulated soft-X-ray transmission speckle patterns from a two-dimensional array of gold balls of 50 nm diameter. The results are relevant to efforts to phase the scattering from many individual macromolecules that cannot be crystallized, and to the scattering from individual inorganic nanoparticles.
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Aires de Sousa M, Crisóstomo MI, Sanches IS, Wu JS, Fuzhong J, Tomasz A, de Lencastre H. Frequent recovery of a single clonal type of multidrug-resistant Staphylococcus aureus from patients in two hospitals in Taiwan and China. J Clin Microbiol 2003; 41:159-63. [PMID: 12517842 PMCID: PMC149637 DOI: 10.1128/jcm.41.1.159-163.2003] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
One hundred thirty-two methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered from patients with S. aureus infections between January 1998 and February 1999 in two hospitals, one located in Taipei, Taiwan, and another in Nanjing, People's Republic of China, were examined for antibiotic susceptibility and for clonal type by a combination of three methods: hybridization of ClaI restriction digests with mecA- and Tn554-specific DNA probes and pulsed-field gel electrophoresis of chromosomal SmaI digests. Selected isolates representing each clonal type were also analyzed by spaA typing, multilocus sequence typing, and a multiplex PCR method capable of identifying the structural type of the staphylococcal cassette chromosome mec (SCCmec) carried by the bacteria. The overwhelming majority of isolates (126 of 132 or 95%) belonged to minor variants of a single clonal type resembling the Brazilian and Hungarian epidemic MRSA clones, which showed a common spaA type and which were either sequence type 239 (ST239) or ST241 (a single-locus variant of ST239) in association with SCCmec type III or IIIA.
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Wu JS, Spence JCH. Kinematic and dynamical CBED for solving thin organic films at low temperature; experimental tests with anthracene. Acta Crystallogr A 2002; 58:580-9. [PMID: 12388877 DOI: 10.1107/s0108767302015830] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2002] [Accepted: 09/03/2002] [Indexed: 11/11/2022] Open
Abstract
Low-dose, low-temperature kinematic and dynamical convergent-beam electron diffraction (CBED) patterns from thin organic crystalline films have been used for the measurement of structure-factor amplitudes and phases. Kinematic conditions are identified by the observation of uniform intensity within the CBED discs and used to determine structure-factor magnitudes. CBED patterns from thicker regions affected by multiple scattering give structure-factor signs, which are varied for best fit. The use of a small probe (and the Kohler SAD mode) minimizes bending artifacts. A new method of thickness determination is evaluated. The approach is tested using experimental data from the centrosymmetric anthracene structure, the results compared with direct methods, and a potential map derived from experimental data. The faint peaks due to H-atom positions may be distinguished. Key issues influencing the validity of the method such as the appropriate dimension of the structure-factor matrix, sample thickness and crystal orientation are discussed.
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Wu JS, Soper NJ. Comparison of laparoscopic choledochotomy closure techniques. Surg Endosc 2002; 16:1309-13. [PMID: 12235508 DOI: 10.1007/s004640080016] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2002] [Accepted: 03/26/2002] [Indexed: 12/26/2022]
Abstract
BACKGROUND Laparoscopic common bile duct exploration (CBDE) has traditionally been accompanied by T-tube drainage. However, other methods of choledochotomy closures have been reported. This study compared three laparoscopic methods of choledochotomy closure in a prospective, randomized fashion to determine which method should be the preferred technique. METHODS In this porcine model, 24 animals initially underwent laparoscopic common bile duct (CBD) clipping to simulate an obstruction. Two days later, the animals underwent laparoscopic clip removal and simulated CBDE through a 1.5-cm choledochotomy. The animals were then randomized to one of three groups: primary choledochotomy closure (group I), antegrade CBD stenting with primary closure (group II), or T-tube placement (group III). To assess for CBD stenoses and leaks, the animals were killed 2 months postoperatively, at which time a cholangiogram was performed and the bile duct harvested. The ratio of proximal CBD to choledochotomy site was assessed radiographically and histologically. RESULTS The operative time was significantly longer in group III (200 +/- 13 min, p < 0.05) than in group I (141 +/- 17 min) and group II (154 +/- 16 min). The ratio of the proximal CBD diameter to the choledochotomy site diameter by cholangiogram was 2.1:1.0 in group I, to 1.2:1.0 in group II, and 1.1:1.0 in group III (p < 0.01). The ratio of the proximal CBD intraluminal area to the choledochotomy site intraluminal area was 2.1:1.0 in group I compared to 1.1:1.0 in groups II and III (p < 0.01). None of the animals developed jaundice or sepsis. CONCLUSION Significant stenoses were present at the choledochotomy site in the primary closure group, and T-tube placement resulted in prolonged operative times. We conclude that laparoscopic antegrade CBD stenting with primary closure of the choledochotomy site is the preferred technique after choledochotomy in an animal model. Further assessment in a clinical trial is warranted.
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Jia SQ, Yong WD, Xu WZ, Xu YY, Wu JS, Chong K, Tan KH, Xu ZH. Existence of homologous sequences corresponding to cDNA of the ver gene in diverse higher plant species. Cell Res 2001; 11:265-71. [PMID: 11787771 DOI: 10.1038/sj.cr.7290095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The presence of DNA homologues corresponding to verc203 (vernalization-related cDNA clone) was investigated by molecular hybridization techniques. The genes were detected in 16 plant species that cover 12 subclasses of the Takhtajan system of angiosperms classification including diverse model species. The results of Southern blot analysis showed a low copy number of this gene existed in rice, wheat, barley and Arabidopsis. The hybridization result of PCR products demonstrated the conservation of the gene corresponding to ver203 in diverse plants. The phylogenetic tree of the ver203 gene in tested plants was supported by evolution relationship of species. The ver203 gene expressed in a vernalized plumule winter wheat, instead of the root. And the endosperm before the treatment was essential for the ver203 expression during vernalization in wheat. In Arabidopsis thaliana, the pattern of expression showed that the gene corresponding to ver203 was expressed at low temperature for 14 days. Gibberellin (GA3) may accelerate the expression of ver203 gene in Arabidopsis exposed to low temperature. However, it could not replace vernalization treatment to initiate the gene expression.
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Wu CH, Yao WJ, Lu FH, Yang YC, Wu JS, Chang CJ. Sex differences of body fat distribution and cardiovascular dysmetabolic factors in old age. Age Ageing 2001; 30:331-6. [PMID: 11509312 DOI: 10.1093/ageing/30.4.331] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The relationship between sexual differences of body fat distribution and cardiovascular dysmetabolic factors in old people is controversial. OBJECTIVES To use centrality index-derived body fat distribution to clarify its relationship with glucose tolerance status, blood pressure and lipid profile. DESIGN Cross-sectional survey in a tertiary-care medical centre in Tainan, Taiwan. SUBJECTS 114 men and 101 women, aged > or = 60 years. METHODS We measured total % body fat and body fat distribution (reflected as centrality index) by dual energy x-ray absorptiometry, and plasma glucose, glycosylated haemoglobin, blood pressure, total cholesterol, triglyceride, high-density lipoprotein (HDL) cholesterol and atherogenic index (total cholesterol/HDL cholesterol). RESULTS Centrality index showed better linear correlation with cardiovascular dysmetabolic factors than body mass index, total % body fat and waist-to-hip ratio, except in systolic blood pressure. Women had higher total % body fat, but the % abdominal fat and centrality index were both higher in men. Subjects with diabetes mellitus had the highest centrality index compared with those with impaired or normal glucose tolerance. After adjustment for age and total % body fat, men still had higher diastolic blood pressure, triglyceride levels and atherogenic indices, but lower HDL cholesterol levels than women. However, when further adjusted for centrality index, the sex differences in cardiovascular dysmetabolic factors were statistically insignificant. CONCLUSIONS Centrality index is a useful method for assessing body fat distribution in older people. Body fat distribution is an important factor in sex differences of cardiovascular dysmetabolic factors in old people.
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Chang CK, Wu JS, Mao DL, Ding CX. Mechanical and histological evaluations of hydroxyapatite-coated and noncoated Ti6Al4V implants in tibia bone. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 2001; 56:17-23. [PMID: 11309786 DOI: 10.1002/1097-4636(200107)56:1<17::aid-jbm1063>3.0.co;2-t] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This paper evaluates the behavior of hydroxyapatite (HAP) coated and noncoated Ti6Al4V implants in dog tibia after 3 and 5 months implantation. HPA-coated implants were obtained by plasma spraying. XRD, SEM, and EPMA were employed to estimate the coating characteristics and their behavior in vivo. Investigation of material characteristics showed that the as-received coatings consisted mainly of amorphism and HAP phase. Other phases such as TCP and CaO were identified due to thermal changes of HAP particles in plasma flame. SEM micrographs showed a typical microstructure of plasma-sprayed coating. The as-received coating was formed by well-melted pancake-like splats that lead to a dense coating with a rough surface. Lamellar structure, micropores, and microcracks, observed inside the coating, are characteristic of plasma spraying. Push-out tests revealed that HAP coating had a significant promotion of interfacial shear strength. The shear strength between bone and HAP-coated implants was much higher than that between bone and noncoated implants due to the different bone-implant interfaces formed after implantation. SEM observation revealed a direct attachment between HAP coating and newly formed bone. However, noncoated implants were separated from newly formed bone by fibrous tissues. Ti ions were found to be released into the surrounding environment after long time immersion in body fluid, and thus caused low shear strength. Prolongation of implantation time had different effects on shear strength. It improved the shear strength between HAP-coated implant and newly formed bone. However, it had little effect on that between noncoated implant and surrounding tissues.
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Khan S, Pawlak SE, Eggenberger JC, Lee CS, Szilagy EJ, Wu JS, Margolin M D DA. Surgical treatment of hemorrhoids: prospective, randomized trial comparing closed excisional hemorrhoidectomy and the Harmonic Scalpel technique of excisional hemorrhoidectomy. Dis Colon Rectum 2001; 44:845-9. [PMID: 11391146 DOI: 10.1007/bf02234706] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
PURPOSE The object of this study was to evaluate technique using the ultrasonically activated scalpel as an alternative to closed hemorrhoidectomy in an unbiased evaluation of this new technology. METHODS Thirty patients with Grade 2 or 3 symptomatic hemorrhoids were prospectively randomized to undergo closed hemorrhoidectomy assisted by electrocautery or hemorrhoidectomy with the ultrasonically activated scalpel, i.e., the Harmonic Scalpel. We evaluated the difference between techniques in operative time, postoperative pain, incontinence, and quality of life (using the Short Form-36 survey), as well as complications. RESULTS Mean operative time for closed hemorrhoidectomy with electrocautery was 35.7 +/- 3 minutes; for Harmonic Scalpel patients, it was 31.7 +/- 2 minutes (P < 0.37). There was no statistical difference in operative time for two- or three-column hemorrhoidectomy. There was no significant difference in pain measurements reported on Day 1 (5.8 +/- 0.4 for electrocautery and 5.6 +/- 0.6 for Harmonic Scalpel, P < 0.82). On postoperative Day 7, the difference in pain between groups approached significance, with pain reported as 3.7 +/- 0.3 for electrocautery and 5.1 +/- 0.7 for Harmonic Scalpel(R) (P < 0.06). At six weeks, both groups were pain free. There was a significant decrease in pain between postoperative Days 1 and 7 in the electrocautery patients that was not seen in the Harmonic Scalpel patients. Incontinence measured preoperatively, at postoperative Day 7, and at postoperative Week 6 was similar for both groups and reflected occasional incontinence of gas. When the various items of the Short Form-36 survey were compared, there was no significant difference between posttreatment and preoperative values. There was no difference in the number of complications between patient groups. CONCLUSION Although the Harmonic Scalpel is an effective tool in the treatment of hemorrhoidal disease, we found no specific advantage in postoperative pain, fecal incontinence, operative time, quality of life, or complications compared with traditional closed hemorrhoidectomy.
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