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Biomedical subjects

W Wang

Publications and source records attributed to W Wang.

At least 37 records · Page 2Linked to original sources
PubMed2006

Dose-related antiallodynic effects of cyclic AMP response element-binding protein-antisense oligonucleotide in the spared nerve injury model of neuropathic pain.

A transcription factor known as cyclic AMP response element-binding protein has been shown to be involved in the central sensitization in neuropathic pain and inflammation pain. The present study examined the roles of cyclic AMP response element-binding protein and of the phosphorylated cyclic AMP response element-binding protein in the maintenance of mechanical and cold allodynia induced by a neuropathic pain model, "spared nerve injury," in rats. First, the results of immunohistochemical study showed that phosphorylated cyclic AMP response element-binding protein, but not cyclic AMP response element-binding protein, increased bilaterally in the spinal dorsal horn 14 days following spared nerve injury, indicating a possible contribution of phosphorylated cyclic AMP response element-binding protein in spared nerve injury. Second, chronic intrathecal application of cyclic AMP response element-binding protein antisense oligodeoxynucleotide with three doses (10 microg/day, 20 microg/day and 40 microg/day) for 5 days demonstrated that the higher doses (20 and 40 microg) significantly attenuated both mechanical (bilaterally) and cold (ipsilaterally) allodynia, compared with sense oligodeoxynucleotide and the lower dose (10 microg). Western blot results showed that the alleviation in intensity of behavioral performance was accompanied by a significant reduction of total cyclic AMP response element-binding protein and phosphorylated cyclic AMP response element-binding protein in the spinal dorsal horn. Moreover, there were no differences in cyclic AMP response element-binding protein and phosphorylated cyclic AMP response element-binding protein between ipsilateral and contralateral dorsal horns. Our data demonstrate a close association between the expression of behavioral hypersensitivity and cyclic AMP response element-binding protein activation in the spinal dorsal horn following spared nerve injury, supporting the notion that phosphorylated cyclic AMP response element-binding protein may play an important role in the maintenance of chronic neuropathic pain.

Animals↗
PubMed2006

Dynamics of the O(3P) + H2 reaction at low temperatures: comparison of quasiclassical trajectory with quantum scattering calculations.

Quasiclassical trajectory and quantum-mechanical scattering calculations are reported for the O((3)P) + H(2)(X (1)Sigma(g) (+);upsilon = 1-3,j = 0)-->OH(X (2)Pi) + H((2)S) reaction at energies close to the reaction threshold. The dynamics of the reaction have been investigated for zero total angular momentum using the lowest (3)A" potential-energy surface developed by Rogers et al. [J. Phys. Chem. A 104, 2308 (2000)] and its recent extensions by Brandao et al. [J. Chem. Phys. 121, 8861 (2004)] which provide an improved description of the van der Waals interaction. Good agreement is observed for this system between quasiclassical and quantal results for incident kinetic energies above the tunneling regime. Quantum-mechanical calculations also confirm recent theoretical predictions of a strong collision-energy dependence of the OH(v(') = 0)OH(v' = 1) product branching ratio in the O((3)P) + H(2)(v = 1) reaction, which explains the differences observed in OH vibrational populations between experiments using different O((3)P) sources.

Journal Article↗
PubMed2006

Use of body mass index to identify obesity-related metabolic disorders in the Chinese population.

OBJECTIVE: To identify the body mass index (BMI; in kg/m2) cutoff that predicts the risk for obesity-related metabolic disorders for the Chinese population. DESIGN: Community-based cross-sectional survey. SETTING: Rural regions of Jiangxi and Anhui provinces and an urban community of Jing'an District of Shanghai, China. SUBJECTS: Five hundred and twenty-nine non-pregnant, non-lactating urban and rural adults, aged 20-64 years without diagnosed diabetes. RESULTS: Subjects were divided into two groups: with or without obesity-related metabolic disorders, which was defined as having at least one of the following: hypertension, insulin resistance, high plasma triacylglycerol, low-density lipoprotein-cholesterol or glucose. Gender-specific multiple logistic regression analysis demonstrated a significant dose-response relationship between BMI and obesity-related metabolic disorders, after adjusting for potential confounders. The lowest BMI interval associated with significant risk for both men and women (odds ratios of 2.67 and 3.46, respectively) was that of 22.5-24.4. Receiver-operating characteristic (ROC) curve analysis indicated that a BMI cutoff of 23 had the best combination of sensitivity and specificity and the shortest distance in the ROC curve, with positive and negative predictive values of 0.6-0.7 in both genders. CONCLUSIONS: A BMI cutoff of 23 might be appropriate for use in identification of high risk of obesity-related metabolic disorders and serve as a public health action threshold in the Chinese population. SPONSORSHIP: Center of a Livable Future, John Hopkins Bloomberg School of Public Health.

Adult↗
PubMed2006

Anti-inflammatory effects of inhaled nitric oxide are optimized at lower oxygen concentration in experimental Klebsiella pneumoniae pneumonia.

OBJECTIVE AND DESIGN: To evaluate whether antiinflammatory effects of inhaled nitric oxide (NO) in experimental Klebsiella pneumoniae pneumonia may be affected by oxygen levels in association with cytokine response and NO synthase (NOS) activity. SUBJECTS AND TREATMENT: Healthy adult rats were intratracheally instilled with live Klebsiella pneumoniae to induce pneumonia (P) or with sterile saline as a control (C) group. Group C was allocated to room air (CA) and inhaled NO (CNO, NO = 20 parts per million) groups. Group P was divided into 6 groups (n = 8 - 10) exposed to room air (PA), inhaled NO (PNO), low oxygen (40%, PLO), inhaled NO and low oxygen (PLONO), high oxygen (100%, PHO), and inhaled NO and high oxygen (98%, PHONO). After 24 h exposure, intraalveolar cells, expression of proinflammatory cytokines, nuclear transcription factor (NF-kappaB), myeloperoxidase (MPO) and NOS activities, characteristic of lung inflammatory mechanisms, were measured. RESULTS: All the pneumonia groups had pneumonia whereas CA and CNO had no or mild lung inflammation. Compared to the PA, significantly decreased recruitment of alveolar neutrophils was found in the PNO, along with lower NF-kappaB and MPO activity, tumor necrosis factor-alpha (TNF-alpha) and intercellular adhesion molecule-1 (ICAM-1). Similar trends were found between the PLONO and PLO in alleviation of lung inflammation. However, PHONO significantly enhanced recruitment of alveolar neutrophils and pulmonary MPO activity associated with increased TNF-alpha. Inhaled NO improved bacterial clearance, reduced total proteins in alveoli, and ICAM-1 expression irrespective of oxygen levels. Inhaled NO and/or low and high oxygen partially restored constitutive NOS activity whereas high oxygen or together with inhaled NO depressed inducible NOS activity. CONCLUSIONS: The overall beneficial effects of inhaled NO in anti-inflammation in the mature lungs with K. pneumoniae pneumonia are in favor of a combination with lower level of oxygen, which warrants clinical verification in the treatment of lung inflammatory injury.

Animals↗
PubMed2006

Interference of cyclosporine on glucose metabolism: potential role in chronic transplantation kidney fibrosis.

OBJECTIVES: To explore the fibrosis induction effects of cyclosporine (CsA) on renal tubular epithelial cells, as well as the potential mechanisms of CsA-mediated alterations of glucose metabolism in chronic allograft nephropathy (CAN). METHODS: The rat renal tubular epithelial cell line NRK-52E cells were cultured in medium with 50 mmol/L of D-glucose for 7, 14, or 28 days. The expression of TGF-beta1, CTGF, Smad3, and Smad7, which are involved in the fibrosis signal pathway, was detected by immunofluorescence and reverse-transcriptase polymerase chain reaction. Meanwhile, cells were cultured in various concentration of CsA in glucose-free medium for 24 hours followed by the addition of D-[3-(3)H]-glucose for 30 minutes; glucose uptake was detected by examining the radiation intensity. RESULTS: The expression of TGF-beta1, Smad3, Smad7, and CTGF of NRK-52E cells were up-regulated significantly (P < .05) after culture with 50 mmol/L glucose for 7 days compared with those in 25 mmol/L glucose. At 14 and 28 days, TGF-beta1 was slightly decreased compared with 7 days, but CTGF, Smad3, and Smad7 increased robustly (P < .05). CsA significantly stimulated glucose uptake at various concentrations, with an absorption peak at 60 minutes that decreased at 75 minutes. Furthermore, CsA may have dose-dependent effects on glucose uptake. CONCLUSION: High glucose concentrations may play an important role in the NRK-52E cell fibrosis during the CAN process due to an interference of CsA on glucose metabolism.

Animals↗
PubMed2006

Nuclear translocation of SMAD3 may enhance the TGF-beta/SMADS pathway in high glucose circumstances.

OBJECTIVES: Posttransplant diabetes mellitus is one of the most frequent complications after kidney transplantation. It is considered to be one cause of chronic allograft nephropathy. This study sought to investigate the effects of high glucose on the expression and nuclear translocation of Smad3, which is an important signal mediator involved in the fibrotic signal pathway. METHODS: The established rat renal mesangial cell line HBZY-1 was cultured in medium with various concentrations of glucose (4.5 mg/mL, 9.0 mg/mL, or 13.5 mg/mL), which was collected at 7, 14, or 21 days. The total expression of Smad3, including both inner and outer nucleus proteins was examined by Western blot analysis. The nuclear translocated Smad3, representing only the inner nucleus protein, was detected by immunofluorescence staining observed under a laser confocal scanning microscope. RESULTS: No significant difference in the total Smad3 expression was demonstrated by Western blot analysis among the three groups of HBZY-1 cells at various concentration of glucose after 7, 14, or 21 days. There was no fluorescence detected in the nucleus at day 7 by immunofluorescence staining; however, robust positive expression of Smad3 was detected at days 14 and 21. CONCLUSION: As a restricted Smads member, Smad3 protein might not be upregulated in the presence of high glucose. However, with prolonged culture time, Smad3 translocates from cytoplasm to nucleus, which may be a pivotal step in the fibrotic signal pathway.

Animals↗
PubMed2006

The C-terminal peptide of connective tissue growth factor blocks the full molecule binding to tubular epithelial cell.

OBJECTIVES: Interstitial fibrosis is a critical pathologic change in chronic allograft nephropathy. The cytokine connective tissue growth factor (CTGF, also CCN2) plays an important role in epithelial-mesenchymal transformation (EMT) of tubular epithelial cells to renal interstitial fibrosis. The hexadeca-peptide within the C-terminal of CTGF (named P2) contains the unique binding domain of CTGF to its potential receptor, integrin alphavbeta3. This study examined whether P2 bound preferentially to the receptor and served as an inhibitor of CTGF. METHODS: All studies used an established rat kidney tubular epithelial cell line NRK-52E. Chemically synthesized P2 was purified, and some of it labeled with FITC. The affinity of CTGF or P2 to NRK-52E cells was examined by a solid-phase cell adhesion assay. Competitive binding between P2 and CTGF to NRK-52E cells was examined with flow cytometric analysis. RESULTS: Both P2 and CTGF bound to the NRK-52E cells, mediating cell adhesion. When the cells were incubated in the mixture of P2 and CTGF, P2 bound to the cells preferentially. Furthermore, when cells were preincubated with excessive CTGF, it became difficult for subsequent P2 binding to occur. CONCLUSIONS: P2 and CTGF seemed to bind to cell membranes at the same binding domain. P2 competitively blocked CTGF binding, acting as a CTGF inhibitor.

Animals↗
PubMed2006

Long-term outcome of combined penetrating keratoplasty and vitreoretinal surgery using temporary keratoprosthesis.

PURPOSE: To evaluate the long-term outcome of combined penetrating keratoplasty (PKP) and vitreoretinal surgery using temporary keratoprosthesis (TKP). METHODS: A retrospective study of 107 eyes with coexisting corneal and vitreoretinal diseases that underwent combined PKP and vitreoretinal surgery using TKP. Corneal graft clarity, intraocular pressure, and anatomical reattachment of retina were followed. RESULTS: The mean follow-up time was 25 months, the longest being 8 years. Successful surgical outcome was defined as maintenance of clear graft, anatomic reattachment of retina, and controlled intraocular pressure. A total of 78 eyes (72.9%) fulfilled these criteria. Surgical intervention within 1 month of ocular injury was associated with higher success rate (81.9%) than intervention at 1 month or more after injury (54.3%). Success rate for reattachment of retina was 95.8% when preoperative proliferative vitreoretinal retinopathy (PVR) was absent compared with 83.1% when preoperative PVR was present. Unsatisfactory postoperative visual acuity was due to graft failure, recurrent PVR, or secondary glaucoma. CONCLUSION: Combined PKP and vitreoretinal surgery is best performed within 1 month of ocular injury for best surgical outcome. Careful selection of cases plays an important role in reducing the risks of complications. TKP is a useful adjunct in the surgery.

Adolescent↗
PubMed2006

Biphasic changes of epithelial sodium channel abundance and trafficking in common bile duct ligation-induced liver cirrhosis.

We hypothesize that dysregulation of the epithelial sodium channel (ENaC) may be responsible for the increased sodium retention in liver cirrhosis. Liver cirrhosis was induced by common bile duct ligation (CBDL). We examined the abundance of ENaC subunits and type 2 isoform of 11beta-hydroxysteroid dehydrogenase (11betaHSD2) in the kidney by immunoblotting and immunohistochemistry at 6 or 8 weeks after operation. At 6 weeks, cirrhotic rats had developed ascites and displayed a positive sodium balance. The urinary sodium excretion and fractional excretion of sodium were decreased, while plasma aldosterone was unchanged. The abundance of ENaC subunits was not changed in the cortex and outer stripe of the outer medulla (OSOM). In contrast, immunoperoxidase microscopy revealed an increased apical targeting of alpha-, beta- and gammaENaC in late distal convoluted tubule, connecting tubule and collecting duct. Moreover, 11betaHSD2 abundance was decreased in the cortex/OSOM and inner stripe of the outer medulla. At 8 weeks, urinary sodium excretion and fractional excretion of sodium were not changed, while the plasma aldosterone level was decreased. The expression of ENaC subunits was decreased in the cortex/OSOM. Immunoperoxidase microscopy confirmed decreased expression of ENaC subunits, whereas subcellular localization was not changed. These results suggest that increased apical targeting of ENaC subunits and diminished abundance of 11betaHSD2 may contribute to promote sodium retention in the sodium-retaining stage of liver cirrhosis (at 6 weeks). The subsequent decreased expression and reduced targeting of ENaC subunits may play a role in promoting sodium excretion in the later stage of liver cirrhosis (at 8 weeks).

11-beta-Hydroxysteroid Dehydrogenase Type 2↗
PubMed2006

Combining genetics and population history in the study of ethnic diversity in the People's Republic of China.

Genomic data have increasingly been used to complement linguistic, archeological, and anthropological evidence in reconstructing the origins and migratory patterns of modern humans. East Asia is a particular hotspot of human migration, especially mainland China, where a large number of human fossils have been unearthed and more than 20% of the world's population now resides. There are 56 officially recognized ethnic populations (minzu) in China. In the present study we investigated the ancestry and genetic diversity of nine populations: the majority Han of Liaoning Province; the Miao, Yao, Kucong, and Tibetan communities of Yunnan Province in southwest China; and four Muslim populations, the Hui, Bonan, Dongxiang, and Sala from central and northern China. We used both biparental and uniparental markers to determine patterns of diversity at autosomal, mitochondrial, and Y-chromosome loci. The study populations displayed several paternal origins but restricted maternal ancestries. From the Y-chromosome data in particular, major demographic changes, such as the Neolithic population expansion and more recent historical events including migration along the Silk Road, could be inferred. Specific aspects of the internal structure and organization of the study populations, including endogamy and consanguinity, were uncovered using autosomal markers. However, we encountered interpretive problems in terms of the definition of the present-day ethnic study populations in China, which appear to reflect past and present political as well as genetic influences.

China↗
PubMed2006

Angiographic follow-up of cerebral aneurysms treated with Guglielmi detachable coils: an analysis of 162 cases with 173 aneurysms.

BACKGROUND AND PURPOSE: The endovascular approach, with the use of Guglielmi detachable coils (GDC), has been increasingly used to treat ruptured and unruptured cerebral aneurysms in recent years. Our objective was to assess the mid- to long-term radiologic outcome of cerebral aneurysms treated with GDC embolization. METHODS: One hundred and sixty-two patients with a total of 173 aneurysms embolized with GDCs underwent angiographic follow-up 1 to 54 months after the procedure and were reviewed retrospectively. Each angiogram was reviewed by 2 neuroradiologists and 1 neurosurgeon, each of whom made a comparison between the initial and follow-up angiograms. Morphologic outcomes were scored as follows: unchanged, progressive thrombosis, and reopening or regrowth. RESULTS: Of the 173 aneurysms with GDC embolization, 142 had total or nearly total occlusion, 23 subtotal occlusion, and 8 partial occlusion on the initial angiograms. The incidence of reopening was 17.1% (13/76) in less than 3 months and 6.2% (6/97) between 3 and 6 months after the procedure. Four aneurysms (2.3%) were found to be recurrent in the second follow-up angiography within 1 year after the procedure. The 1-year cumulative recurrent rate was 13.3%. Among 56 aneurysms with a third follow-up angiography in the period of 12 to 54 months after the procedure, 4 (7.1%) displayed a slight enlargement; the long-term cumulative recurrent rate was 20.4%. CONCLUSION: The direct and primary causes for aneurysmal recurrence are incomplete and loose packing. The first angiographic follow-up is recommended to be performed at 3 months or earlier for incompletely occluded aneurysms and at 6 months for totally or nearly totally occluded aneurysms. In case of total or nearly total occlusion that remains stable at follow-up, the interval for monitoring should be prolonged appropriately. Retreatment with balloon- or stent-assisted coil embolization is recommended for reopened aneurysms.

Adolescent↗
PubMed2006

Spectral karyotyping and fluorescence in situ hybridization analysis of de novo partial trisomy 7p (7p21.2-->pter) and partial monosomy 12q (12q24.33-->qter).

An 8-year-old boy presenting with hypotonia, moderate mental retardation, developmental delay, and psychomotor retardation is reported. Magnetic resonance imaging of the brain at age 3 years revealed a Dandy-Walker variant. Cytogenetic analysis of the peripheral blood revealed a derivative chromosome 12 with unknown additional material attached to the distal region of the long arm of chromosome 12. The parental karyotypes were normal. Spectral karyotyping (SKY) using the 24-color SKY probes and fluorescence in situ hybridization (FISH) using the specific 7p, 7q, 12p, and 12q telomeric probes confirmed a duplication of distal 7p and a deletion of terminal 12q. The karyotype of the proband was designated as 46,XY.ish der(12)t(7;12) (p21.2;q24. 33)(SKY+, 7pTEL+, 12qTEL-). The present case provides evidence for the association of partial trisomy 7p (7p21.2-->pter) and partial monosomy 12q (12q24.33-->qter) with a cerebellar malformation and the usefulness of SKY and FISH in the identification of a de novo aberrant chromosome resulting from an unbalanced translocation.

Child↗