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Ning Wu

Publications and source records attributed to Ning Wu.

At least 37 records · Page 2Linked to original sources

Impact of cognitive function on assessments of nursing home residents' pain.

OBJECTIVES: We sought to examine the impact of residents' cognitive function on the quality of Minimum Data Set (MDS) pain data using the latent variable approach. RESEARCH DESIGN: Using the Resident Assessment Instrument (RAI) protocol, nursing home (NH) staff and well-trained study nurses independently assessed 3736 NH residents. MEASURES: Inter-rater agreement of pain ratings between NH staff and study nurses was quantified by weighted kappas and polychoric correlations and compared among groups of residents with no/mild, moderate, and severe cognitive impairment. Probit models were built to examine the effect of residents' cognitive function on thresholds raters used to rate pain. RESULTS: Of 3736 residents, 40.4% had no/mild, 35.9% moderate, and 23.7% severe cognitive impairment. Both NH staff and study nurses recorded less frequent and less severe pain for residents with more severe cognitive impairment. The inter-rater agreement on pain ratings between NH staff and study nurses was good-weighted kappas were greater than 0.5 and polychoric correlations greater than 0.7. The thresholds raters used to record pain were similar for NH staff and study nurses and progressively increased when raters recorded pain for residents with more severe cognitive impairment. CONCLUSIONS: Given the RAI protocols, the quality of MDS pain data collected by NH staff was similar to that of well-trained nurses regardless of residents' cognitive function. Our results strongly support the notion that specialized pain assessment instruments are needed to adequately detect pain for the large proportion of cognitive impaired NH residents.

Aged↗

The quality of the quality indicator of pain derived from the minimum data set.

OBJECTIVE: To examine facility variation in data quality of the level of pain documented in the minimum data set (MDS) as a function of level of hospice enrollment in nursing homes (NHs). DATA SOURCE: Clinical assessments on 3,469 nonhospice residents from 178 NHs were merged with On-line Survey Certification and Reporting data of 2000, Medicare Claims data of 2000 and the MDS of 2000-2002. STUDY DESIGN: Using the same assessment protocol, NH staff and study nurses independently assessed 3,469 nonhospice residents. Study nurses' assessments being gold standard, we quantified and compared quality of NH staff's pain rating across NHs with high, medium, or low hospice use. Multilevel models were built to assess the effect of NH hospice use levels on the occurrence of false positive (FP) and false negative (FN) errors in NH-rated "severe pain." PRINCIPAL FINDINGS: Of 178 NHs, 25 had medium and 41 high hospice use. NHs with higher hospice use had lower sensitivities. In multilevel analysis, we found a significant facility-level variation in the probability of FP and FN errors in facility-rated "severe pain." Resident characteristics only explained 4 and 0 percent of the facility variation in FP and FN, respectively; characteristics and locations (state) of NHs further explained 53 and 52 percent of the variance. After controlling for resident and NH characteristics, staff in NHs with medium or high hospice use were less likely to have FP or FN errors in their MDS documentation of pain than were staff in NHs with low or no hospice use. CONCLUSIONS: The examination of data quality of pooled MDS data from multiple NHs is insufficient. Multilevel analysis is needed to elucidate sources of heterogeneity in the quality of MDS data across NHs. Facility characteristics, e.g., hospice use or NH location, are systematically associated with overrated/underrated pain and may bias pain quality indicator (QI) comparisons. To ensure the integrity of QI comparison in the NH setting, the government may need to institute regular audits of MDS data quality.

Aged↗

[Effects of ligustrazine on expression of VCAM-1/VLA-4 in syngenic bone marrow transplantation of mice].

To explore the effect of ligustrazine on the expression of adherent molecule VCAM-1/VLA-4 of bone marrow cells in syngenic bone marrow transplantation (BMT) mice, the mice were divided into 3 groups: normal group (which received no treatment), BMT control group and ligustrazine-treated groups. BMT mouse models were established. The BMT control group and the ligustrazine-treated group were orally administered 0.2 ml saline per mouse and 2 mg ligustrazine per mouse, respectively, twice a day. On the day 7, 14, 21, 28 after BMT, mice were respectively killed. Bone marrow nucleated cells were detected, and then the expression of VCAM-1/VLA-4 was assayed by immunohistochemistry, RT-PCR and flow cytometry analysis, respectively. The results showed that in ligustrazine-treated group, the accounts of bone marrow nucleated cells on the day 7, 14, 21, 28 after BMT were all higher than that in BMT control group. The expression level in the ligustrazine-treated group was significantly higher than that in the BMT control group (P < 0.05 or P < 0.01). It is concluded that ligustrazine can enhance VCAM-1/VLA-4 expression in bone marrow after syngenic bone marrow transplantation in mice, which may be related to the mechanisms underlying the ligustrazine accelerating hematopoietic reconstitution in allogenic bone marrow transplantation.

Animals↗

Inhibitory effect of agmatine on proliferation of tumor cells by modulation of polyamine metabolism.

AIM: To assess the inhibitory effect of agmatine on tumor growth in vivo and tumor cell proliferation in vitro. METHODS: The transplanted animal model, [3H]thymidine incorporation assay,3-[4,5-dimethythiazol-2-yl]-2,5-diphenyltetrazolium assay, and lactate dehydrogenase (LDH) release assay were performed. RESULTS: Agmatine, at doses of 5-40 mg/kg, suppressed the S180 sarcoma tumor growth dose-dependently in mice in vivo and the highest inhibitory ratio reached 31.3% in Kunming mice and 50.0% in Balb/c mice, respectively. Similar results were obtained in the transplanted B16 melanoma tumor model. Agmatine (1-1000 micromol/L) was able to attenuate the proliferation of cultured MCF-7 human breast cancer cells in vitro in a concentration-dependent manner and the highest inhibitory ratio reached 50.3% in the [3H]thymidine incorporation assay. Additionally, in the LDH release assay, spermine (20 micromol/L) and spermidine (20 micromol/L) increased the LDH release significantly, but agmatine (1-1000 micromol/L) did not, indicating that the inhibitory effect of agmatine on the proliferation of MCF was not related to cellular toxicity. In the [3H]thymidine incorporation assay, putrescine (12.5-100.0 micromol/L) could reverse the inhibitory effect of agmatine on the proliferation of MCF concentration-dependently, suggesting that the inhibitory effect of agmatine on the proliferation of MCF might be associated with a decreased level of the intracellular polyamines pool. CONCLUSION: Agmatine had significant inhibitory effect on transplanted tumor growth in vivo and proliferation of tumor cells in vitro, and the mechanism might be a result of inducing decrease of intracellular polyamine contents.

Agmatine↗

[Sabina przewalskii community structure in the upper reaches of Minjiang River].

In this paper, the physiognomy and the structure of Sabina przewalskii community were studied by sample plot method. The results showed that in the life spectrum of the community, hemicryptophyte was dominated, but therophytes also occurred frequently, which presented some features of temperate vegetation. The vertical structure of the community was quite simple, consisting of tree layer, shrub layer and herb layer, and there were no interstratum plants and ground layer. Sabina przewalskii was the only species in the tree layer. In fruticose stratum, the important value of Spiraea alpina was 153.3, ranking the first; while in herb layer, the important value of Carex caespifosa ranked the first, amounting to 36.8. Among the three plot groups on different slopes, spiny-shrubs such as Berberis wilsonae and Caragana erinacea grown on small slope were more than those on bigger slope, so did unpalatable grasses such as Pedicularis axillaries and Artemisia tauguticat, which mainly owed to retrogressive succession caused by frequently grazing. The age and height structures of Sabina przewalskii population indicated a declining trend, and the community would develop retrogressively if disturbances (e.g., grazing) could not be reduced. The disturbance caused by livestock was more obvious in the plot group on small slope than on bigger slope, and livestock mainly destroyed seedlings and small trees, which made tree population be impossible to regenerate. The coverage of upper layers had a notable impact on the lower layers, and there wasn't any correlation between coverage and diversity index (Shannon-Wiener Index) in each layer.

Ecosystem↗

[The diagnostic value of dynamic CT in solitary pulmonary nodules: a prospective study].

OBJECTIVE: To evaluate imaging features of benign and malignant solitary pulmonary nodules (SPN) using dynamic computed tomography (dCT) to improve the accuracy of radiological diagnosis. METHODS: Fifty-one patients with SPN were studied by dCT. In this procedure, a bolus of 100 ml contrast medium was administrated intravenously at a rate of 4 ml/sec. The same-located dynamic scans were carried out from 15 sec to 120 sec following the injection. Time-attenuation curves (TAC) were created according to circular or oval ROI drawn over nodules. Histopathological diagnosis was considered as the golden standard in all patients. Double-blind examination and evaluation were carried out and the data were analyzed statistically with Mann-Whitney U test. RESULTS: Thirty eight cases were diagnosed to be malignant SPN (mSPN) and 13 cases to be benign SPN (bSPN). The benign SPN were further divided into two groups, bSPN(1) consisting 6 cases with chronic pneumonitis, nodular tuberculosis or sclerosing hemangioma and bSPN(2) consisting 7 cases with tuberculoma, pulmonary cyst, pulmonary sequestration or mycosis ball. There were statistically significant differences between mSPN and bSPN(2) in peak heights of enhancement (87.6 HU vs. 57.8 HU, P < 0.01), enhancement values (peak heights- unenhanced CT values, 59.6 HU vs. 11.1 HU, P < 0.01). However, no statistically significant differences of those two values existed between mSPN and bSPN(1). TAC of mSPN reached to peak height more rapidly and remained a plateau. TAC of bSPN(1)s showed similar changes to that of mSPN despite a delayed reach to a peak height or even a descending branch. TAC of the bSPN(2)s was lower and flatter without peak height. If a threshold of 20 HU was taken for dCT, the lesions with < or = 20 HU were diagnosed as benign, and the lesions with > 20 HU were diagnosed as malignant, with a sensitivity of 100%, a specificity of 54.0% and an accuracy of 88.4%. CONCLUSION: (1) Absence of the marked enhancement (< or = 20 HU) in dynamic CT is strongly predictive of benignancy. (2) The peak height and enhancement value of dCT are helpful to differentiate malignant SPNs from benign ones. (3) The TAC configuration is helpful in differentiating malignant SPNs from benign ones. Descending branches could be found in some benign lesions, but not in the malignant ones. The TAC of tuberculoma and mycosis ball is usually relatively low and flat without any peak height.

Adenocarcinoma↗

[The value of erythrocyte sedimentation rate and C-reactive protein in evaluating disease activity in ankylosing spondylitis].

OBJECTIVE: To determine whether erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) is more appropriate in measuring the disease activity in ankylosing spondylitis (AS). METHODS: We studied 126 consecutive patients with AS. The external criteria for disease activity were Cowling clinical assessment of disease activity and the Bath AS disease activity index (BASDAI). In each measure we defined 3 levels of disease activity i.e. no activity, ambiguous activity and definite activity. The patients with AS were divided into 2 groups: those with spinal involvement only and those with peripheral arthritis as well. For each criterion of disease activity, the patients without activity and with definite activity were included in receiver operating characteristic curve, which was used to determine cutoff values with the highest sensitivity and specificity. We also calculated Spearman correlation. RESULTS: The median ESR and CRP were 25.3 mm/1 h and 11.1 mg/L in the spinal group and 30.0 mm/1 h and 15.0 mg/L in the peripheral group. In both groups the Spearman correlation coefficients between ESR and CRP were around 0.30. There was no correlation between ESR, CRP, and the 2 disease activity variables (0.027-0.282). Sensitivity for both ESR and CRP was between 39.4 %and 81.3% for Cowling assessment of disease activity and the BASDAI, while specificity was between 40.0% and 86.7% for all disease activity measures. CONCLUSION: It is concluded that neither ESR nor CRP is superior for assessing disease activity in ankylosing spondylitis.

Adult↗

A genetically encoded photocaged amino acid.

We have developed a second orthogonal tRNA/synthetase pair for use in yeast based on the Escherichia coli tRNALeu/leucyl tRNA-synthetase pair. Using a novel genetic selection, we have identified a series of synthetase mutants that selectively charge the amber suppresor tRNA with the C8 amino acid, alpha-aminocaprylic acid, and the photocaged amino acid, o-nitrobenzyl cysteine, allowing them to be inserted into proteins in yeast in response to the amber nonsense codon, TAG.

Base Sequence↗

Validation and application of an automated 96 -well solid-phase extraction liquid chromatography-tandem mass spectrometry method for the quantitative determination of SCH 201781 in human plasma.

SCH 201781 is a direct thrombin inhibitor recently under study in clinical trials to determine its safety and efficacy for the treatment of venous and arterial thrombosis. In aqueous solution, SCH 201781 exists as three forms, a ring-opened hydrated form and two ring-closed diastereomers. An automated solid-phase extraction LC-MS/MS method that chromatographically separates and measures each form was developed and validated from 1 to 1000 ng/mL in human plasma. For calibration curve standards, within- and between-run precision (%CV) ranged from 0.6 to 13.7%, while accuracy (%bias) ranged from -4.8 to 13.1%. For quality control samples, within- and between-run %CV ranged from 1.5 to 9.9% while %bias ranged from -9.1 to 4.9%. The method requires a sample volume of 0.8 ml and utilizes 2H6-labeled SCH 201781 as the internal standard. For sample processing, an Isolute C-8 96-well solid phase extraction plate and a Tomtec Quadra 96 sample processor is employed. Separation of the three forms of SCH 201781 is achieved using a 5 microm, 2 mm x 100 mm Asahipak C8 HPLC column and gradient elution. A Sciex API 365 equipped with a turbo ionspray source is used in the selected reaction monitoring mode for detection. The validated method was used to support clinical studies.

Antithrombins↗

The site-specific incorporation of p-iodo-L-phenylalanine into proteins for structure determination.

A recently developed method makes it possible to genetically encode unnatural amino acids with diverse physical, chemical or biological properties in Escherichia coli and yeast. We now show that this technology can be used to efficiently and site-specifically incorporate p-iodo-L-phenylalanine (iodoPhe) into proteins in response to an amber TAG codon. The selective introduction of the anomalously scattering iodine atom into proteins should facilitate single-wavelength anomalous dispersion experiments on in-house X-ray sources. To illustrate this, we generated a Phe153 --> iodoPhe mutant of bacteriophage T4 lysozyme and determined its crystal structure using considerably less data than are needed for the equivalent experiment with cysteine and methionine. The iodoPhe residue, although present in the hydrophobic core of the protein, did not perturb the protein structure in any meaningful way. The ability to selectively introduce this and other heavy atom-containing amino acids into proteins should facilitate the structural study of proteins.

Amino Acid Substitution↗

An expanded genetic code with a functional quadruplet codon.

With few exceptions the genetic codes of all known organisms encode the same 20 amino acids, yet all that is required to add a new building block are a unique tRNA/aminoacyl-tRNA synthetase pair, a source of the amino acid, and a unique codon that specifies the amino acid. For example, the amber nonsense codon, TAG, together with orthogonal Methanococcus jannaschii or Escherichia coli tRNA/synthetase pairs have been used to genetically encode a variety of unnatural amino acids in E. coli and yeast, respectively. However, the availability of noncoding triplet codons ultimately limits the number of amino acids encoded by any organism. Here, we report the design and generation of an orthogonal synthetase/tRNA pair derived from archaeal tRNA(Lys) sequences that efficiently and selectively incorporates an unnatural amino acid into proteins in response to the quadruplet codon, AGGA. Frameshift suppression with L-homoglutamine (hGln) does not significantly affect protein yields or cell growth rates and is mutually orthogonal with amber suppression, permitting the simultaneous incorporation of two unnatural amino acids, hGln and O-methyl-L-tyrosine, at distinct positions within myoglobin. This work suggests that neither the number of available triplet codons nor the translational machinery itself represents a significant barrier to further expansion of the genetic code.

Amino Acids↗

Anabaena circadian clock proteins KaiA and KaiB reveal a potential common binding site to their partner KaiC.

The cyanobacterial clock proteins KaiA and KaiB are proposed as regulators of the circadian rhythm in cyanobacteria. Mutations in both proteins have been reported to alter or abolish circadian rhythmicity. Here, we present molecular models of both KaiA and KaiB from the cyanobacteria Anabaena sp PCC7120 deduced by crystal structure analysis, and we discuss how clock-changing or abolishing mutations may cause their resulting circadian phenotype. The overall fold of the KaiA monomer is that of a four-helix bundle. KaiB, on the other hand, adopts an alpha-beta meander motif. Both proteins purify and crystallize as dimers. While the folds of the two proteins are clearly different, their size and some surface features of the physiologically relevant dimers are very similar. Notably, the functionally relevant residues Arg 69 of KaiA and Arg 23 of KaiB align well in space. The apparent structural similarities suggest that KaiA and KaiB may compete for a potential common binding site on KaiC.

Amino Acid Sequence↗

Validation and application of a liquid chromatography-tandem mass spectrometric method for the determination of SCH 211803 in rat and monkey plasma using automated 96-well protein precipitation.

A rapid, sensitive, specific, accurate, and reproducible automated liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for the quantitative determination of 1'-(2-amino-3-methylbenzoyl)-4-[[[(3-chlorophenyl)sulfonyl]phenyl]methyl]-1,4'-bipiperidine hydrochloride (SCH 211803) in plasma has been developed. The method was validated in rat and monkey plasma over the concentration range of 0.5-250 ng/ml using 2H(4)-SCH 211803 as the internal standard (IS). Automated 96-well plate protein precipitation (PP) with acetonitrile (ACN) was used for sample processing. The method employed a Betasil C18 column with a fast gradient for the separation of analyte and internal standard from the plasma matrix and a triple quadrupole mass spectrometer operated in positive ion multiple reaction monitoring (MRM) mode for detection. The method was used for the determination of SCH 211803 plasma concentrations to support pre-clinical studies.

Animals↗

High-throughput gene discovery in the rat.

The rat is an important animal model for human diseases and is widely used in physiology. In this article we present a new strategy for gene discovery based on the production of ESTs from serially subtracted and normalized cDNA libraries, and we describe its application for the development of a comprehensive nonredundant collection of rat ESTs. Our new strategy appears to yield substantially more EST clusters per ESTs sequenced than do previous approaches that did not use serial subtraction. However, multiple rounds of library subtraction resulted in high frequencies of otherwise rare internally primed cDNAs, defining the limits of this powerful approach. To date, we have generated >200,000 3' ESTs from >100 cDNA libraries representing a wide range of tissues and developmental stages of the laboratory rat. Most importantly, we have contributed to approximately 50,000 rat UniGene clusters. We have identified, arrayed, and derived 5' ESTs from >30,000 unique rat cDNA clones. Complete information, including radiation hybrid mapping data, is also maintained locally at http://genome.uiowa.edu/clcg.html. All of the sequences described in this article have been submitted to the dbEST division of the NCBI.

Animals↗

Normal/disease-paired cDNA library subtraction for molecular marker development.

This study consists of a novel strategy for the identification of potential cancer exclusively expressed genes, which might lead to the development of valuable diagnostic molecular markers. Normal- and cancer-paired tissues from the same patient were collected and subjected to the construction of primary complementary deoxyribonucleic acid (cDNA) libraries. The cancer cDNA library was generated by subtracting normal cDNAs from the primary cancer library. The remaining clones in the subtracted cancer library were sequenced and Basic Local Alignment Search Tool (BLAST)-analyzed against current nonredundant and est_human databases in the GenBank. The clones that had no matches with any known gene sequences except the human genomic sequences were identified as ideal candidates for potential molecular marker development. The candidate marker sequence and associated primer sequences were identified on the target clone sequence of the region with the least, or no, matched homologs. The specificity of the markers was measured by a polymerase chain reaction test experiment with the DNA templates from different human normal tissues, genomic DNA, and additional patients' tissues. Results from bioinformatical and experimental approaches used suggest that the methodology has a high potential to identify cancer exclusive transcripts. Thus, it might result in the development of diagnostic markers.

Biotechnology↗

[Effect of forest litter on microenvironment conditions of forestland].

Litter is a very important component in forest ecosystem. This paper made a systematic review on the previous studies about the effects of litter on forestland microsites. Litter significantly reduced the light on the soil surface of forestlands, and the light transmittance was varied with the type, water content and weight of litter. The spectral composition of the light was dramatically shifted to longer wavelengths after transmitted through forest capony, especially through moist litter leaves, intact forest litter, and even the thinner soil layer, which greatly reduced the R/FR ratio and PPFD (photosynthetic photo flux density) beneath litter and surface soil (2 mm depth), and resulted in a stronginhibitory effect on the germination of photoblastic seeds, and on the growth of seedling and sapling. It was the reason why the appearance of massive numbers of pioneer plants and their successful establishment required relatively large gaps of the forest canopy. Many references concerned the effects of litter on soil nutrient cycling and water and soil conservation. The previous studies indicated that litter could create a moist micro-site above soil, and make soil more moist and fertile. Furthermore, litter could also increase the numbers of arthropods such as Carabidae adults and larvae, crickets, millipedes, spiders, ants and others. An increase in the activity of herbivorous arthropods might produce the negative effects on the establishment of individual seedlings. Although the mechanical barrier of litter was neglected in the paper, litter might act as a mechanical impediment to the emergence of the seedlings of pioneer species with small seeds. The effects of litter on micro-sites were of complexity because it varied greatly with the density, age, structure and species composition of the canopy, sunfleck frequency, presence of gaps, as well as litter thickness, moisture, and species composition, and also with climate and topography factors. The effects of litter were comprehensive, including positive and negative effects on seed germination and seedling growth. Each effect of litter on regeneration was dependent on species physiology, litter physical properties and environmental conditions. Therefore, it should be encouraged to integrate the physical properties (such as changing light, temperature and moisture) of litter with the physiological ecology (including seed, germination and growth natures) of species, and with environment (vegeneration, climate and topography propersities) on the basis of combination of regeneration patterns of litter, understory and gap scales.

Animals↗

The effects of interferon-gamma on the expression of the cyclin D isoforms in cord blood hematopoietic stem/progenitor cells.

To explore the hematopoiesis inhibition mechanisms of interferon-gamma (IFN-gamma), the effects of IFN-gamma on the expression of the cyclin D in the umbilical cord blood hematopoietic stem/progenitor cells were observed. In the experiments the CD34(+) cells were isolated from the cord blood with MIDI-MACS system; semi-solid methylcellulose culture technique was used to measure the formation of CFU-GM; the expression levels of cyclin D isoforms were assayed by semi-quantitative RT-PCR, after the hematopoietic stem/progenitor cells were incubated with IFN-gamma. The results indicated that IFN-gamma could inhibit the formation of CFU-GM and down-regulate the expression of cyclin D2 and cyclin D3 at the mRNA level. It is concluded that the IFN-gamma could inhibit the proliferation of hematopoietic stem cells and down-regulate the expression of cyclin D, that may be one mechanism underlying the hematopoietic inhibition of IFN-gamma.

Cyclin D↗

[Effect of ligustrazine on expressions of basic fibroblast growth factor and its receptor in bone marrow of mice with acute radiation injury].

OBJECTIVE: To study the expressions of basic fibroblast growth factor (bFGF) and its receptor (bFGFR) in bone marrow of mice with acute radiation injury, and to evaluate the effect of Ligustrazine (Lt) on them. METHODS: Fifty-six Kunming mice of clean grade were randomly divided into 3 groups, the normal group, the control group and the Lt group. Mice in the latter two groups were once homogeneously systemic irradiated with 6.0 Gy of 60Co, with the absorption dose rate of 0.56 Gy/min, then treated with saline (0.2 ml/mice) or Lt (2 mg/mice) respectively, twice a day through gastrogavage for successive 13 days. Mice were sacrificed in batch on the 3rd, 7th and 14th day by cervical dislocation to collect the bilateral femoral bone marrow for preparing bone marrow mono-nuclear cell (BMMNC) suspension. The bFGFR expression on surface of BMMNC was determined by flow cytometry; and the bFGF expression level in one side of femoral bone marrow tissue was detected by immunohistochemistry with SABC-AP assay. RESULTS: The bFGF expression in bone marrow of mice on the 3rd, 7th and 14th day after acute radiation injury all were significantly lower than that of the normal mice (P < 0.05 or P < 0.01). The expressions of bFGF and bFGFR in the Lt group detected were significantly higher than that in the control group detected at the corresponding time points (P < 0.05 or P < 0.01). CONCLUSION: By way of enhancing bFGF expression in bone marrow and bFGFR expression on surface of BMMNC to accelerate the repairing of homopoietic micro-environment in bone marrow might be one of the mechanisms of Lt in promoting hemopoietic function reconstitution after acute radiation injury.

Animals↗