Search PubMed⌕ Search

Biomedical subjects

Hong Xiao

Publications and source records attributed to Hong Xiao.

At least 37 records · Page 2Linked to original sources
PubMed2005

[Influence of hyperoxic fluid on the down-regulated proteins of intestinal mucosa in scalded rats].

OBJECTIVE: To investigate the influence of hyperoxic fluid on the down-regulated proteins of intestinal mucosa in scalded rats, so as to provide a theoretical basis for the clinical use of hyperoxic fluid. METHODS: Sprague-Dawley (SD) rats with 35% TBSA full-thickness scald were randomly divided into scald control (S, n = 6,with intraperitoneal fluid infusion after scalding), hyperoxic (H, n = 6, with hyperoxic fluid infusion after scalding) groups. Six rats without scald injury served as normal group. The proteins in the intestinal mucosa were separated with the two-dimensional electrophoresis (2-DE), and were analyzed with ImageMaster 2D Elite. The influence of hyperoxic fluid on the down-regulated proteins of intestinal mucosa in scalded rats was studied with bio-spectrum, protein bank and document analysis. RESULTS: (1) Among the 34 down-regulated protein spots in S group, 9 of them definitely exhibited up-regulation compared with those in H group. (2) The expression of mitochondrial aconitase, alpha-propionyl-CoA carboxylase, short chain of hydroxyacyl-Coenzyme A dehydrogenase, transcription factor EB (estradiol benzoate), triosephosphate isomerase 1, T cell receptor V delta 6, and dynein-like protein-5 in H group were significantly up-regulated. CONCLUSION: The hyperoxic fluid could up-regulate the down-regulated proteins in rat intestinal mucosa at early postburn stage, so that the barrier function of intestinal mucosa of rats with severe burns could be partially recovered.

Animals↗
PubMed2005

[The research on the quenching of fluorescence spectra of TOP I by iodine anion].

Comparing the fluorescence spectra of tobacco peroxidase I (TOP I) solution and the solutions titrated by iodine anions, the number of binding locus and the binding constant of iodine anion to TOP I were calculated by using the modified Stern-Volmer equation. The mechanism of the quenching of fluorescence spectra and the distribution of tryptophane residues in the TOP I molecule were discussed.

Algorithms↗
PubMed2005

[Serum leptin level in patients with obstructive sleep apnea-hypopnea syndrome].

OBJECTIVE: To investigate the effect of uvulopalatopharyngoplasty on changes of serum leptin levels in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). METHODS: Sixty-one patients with OSAHS diagnosed by polysomnography were treated with uvulopalatopharyngoplasty. Pretreatment and post-uppp serum leptin concentrations in patients with OSAHS and in BMI-matched controls were measured by radioimmunoassay. Correlations between leptin concentrations and AHI, BMI were analyzed. RESULTS: The concentrations of leptin in patients with OSAHS were higher than that in controls (P < 0.05). Mean levels (x+/-s) of leptin were (9.8+/-2.1) microg/L, (14.2+/-6.7) microg/L, and (19.3+/-7.9) microg/L in patients with severe, mediate and mild obstructive sleep apnea, respectively. Serum leptin levels correlated positively with the degree of OSAHS as reflected by AHI (r = 0. 68, P < 0.01). The leptin concentration of 51 responders after 6 months were significantly decreased (P < 0.01) than that of pre-operation. However, the difference of leptin concentration between pre-operation and post operation was not significant in 9 nonresponders (P > 0.05). CONCLUSIONS: There are higher leptin concentrations in patients with OSAHS, which are significantly correlated to the severity of disease. Serum leptin levels in responders decreased significantly after uvulopalatopharyngoplasty. OSAHS may influence the leptin system, resulting in increased serum leptin level.

Adult↗
PubMed2005

Effect of protein kinase C on proliferation and apoptosis of T lymphocytes in idiopathic thrombocytopenic purpura children.

It is well-documented that T lymphocyte proliferation and apoptosis are abnormal in idiopathic thrombocytopenic purpura (ITP) children. However, the underlying regulation mechanisms especially in terms of signal transduction remain unknown. In this paper, we reported the changes of protein kinase C (PKC) activity in peripheral blood T lymphocytes and the effect of PKC on T lymphocyte proliferation and apoptosis. We demonstrated that in ITP children, the activator (PMA) and inhibitor (H-7) of PKC affected on T lymphocyte proliferation and apoptosis dramatically, but they altered little in healthy children. PKC activity was significantly enhanced in ITP children together with an increased expression of FasL on CD3+T, CD4+T and CD8+T cells, resulting in a positive correlation between PKC activity and the expression of FasL on T cells. While the PKC activity and the platelet count were negatively correlated. Taken together, our findings suggest that the PKC activation may enhance T lymphocytes activity, suppress T cell apoptosis and be involve in thrombocytes damage as a mechanism related to immune pathogenesis of ITP.

Adolescent↗
PubMed2005

Polarization and apoptosis of T cell subsets in idiopathic thrombocytopenic purpura.

It is well-known that idiopathic thrombocytopenic purpura (ITP) is an acquired organ-specific autoimmune hemorrhagic disease and dysfunctional cellular immunity is considered important in the pathophysiology of ITP. However, polarization patterns and apoptosis profiles of T lymphocytes remain unclear. In this study, we investigated the polarization of T cell subsets, the expressions of apoptotic proteins Fas/FasL on the subsets and the level of anti-apoptotic gene bcl-2 and bax mRNA. It was demonstrated that the ratios of Th1/Th2 and Tc1/Tc2 in ITP children were increased obviously and that the average percentages were increased clearly for Th1 and Th2, but not for Tc1 and Tc2. In ITP children, the enhancing expressions were detected for FasL on Th1 and Tc1 and for Fas on Th2 and Tc2. With increasing level of bcl-2 mRNA and decreasing expression of bax mRNA in ITP children, the ratio of bcl-2/bax mRNA was improved obviously, which was positive correlated with the ratio of Th1/Th2. Taken together, our findings indicate that ITP is a Th1 predominant disease. This polarization pattern of T cell subsets might be related to the high ratio of bcl-2/bax mRNA and the abnormal expressions of Fas and FasL on T cell subsets.

Apoptosis↗
PubMed2004

Economic burden of dehydration among hospitalized elderly patients.

PURPOSE: The cost of unnecessary hospitalizations associated with dehydration in elderly patients was studied. METHODS: The study involved a retrospective examination of 1999 data on hospital discharges from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample. The procedure code for volume depletion was used to extract hospitalization episodes for patients > or = 65 years of age who had a principal diagnosis of dehydration and were discharged alive. Hospitalizations with procedure codes unrelated to dehydration were omitted. RESULTS: The descriptive findings indicated that hospitalized older patients with a principal diagnosis of dehydration averaged 80.4 years of age, were primarily white (82.5%), and were more likely to live in the community than in a nursing home. Hospitalizations for dehydration were more common in the South and less common in the West. The average length of stay (LOS) was 4.6 days. The average total hospital charge was dollars 7,442, and the average per diem charge was dollars 1,628. Regression analysis explained nearly half of the variation in charges for dehydration (R2 = 0.457). Average LOS and number of diagnoses were directly related to hospital charges, and age was inversely related. Higher charges were associated with being nonwhite, entering the hospital via the emergency room, having private insurance, having no insurance, having comorbidities, and being hospitalized in the West or in teaching or urban hospitals. In 1999, the potential national saving from avoidable hospitalizations in these patients could have been as much as dollars 1.14 billion. CONCLUSION: The economic burden associated with avoidable hospitalizations due to dehydration in elderly patients was substantial.

Aged↗
PubMed2004

Alanine-scanning mutagenesis of the beta-sheet region of phage T4 lysozyme suggests that tertiary context has a dominant effect on beta-sheet formation.

In general, alpha-helical conformations in proteins depend in large part on the amino acid residues within the helix and their proximal interactions. For example, an alanine residue has a high propensity to adopt an alpha-helical conformation, whereas that of a glycine residue is low. The sequence preferences for beta-sheet formation are less obvious. To identify the factors that influence beta-sheet conformation, a series of scanning polyalanine mutations were made within the strands and associated turns of the beta-sheet region in T4 lysozyme. For each construct the stability of the folded protein was reduced substantially, consistent with removal of native packing interactions. However, the crystal structures showed that each of the mutants retained the beta-sheet conformation. These results suggest that the structure of the beta-sheet region of T4 lysozyme is maintained to a substantial extent by tertiary interactions with the surrounding parts of the protein. Such tertiary interactions may be important in determining the structures of beta-sheets in general.

Alanine↗
PubMed2004

The Chinese Visible Human (CVH) datasets incorporate technical and imaging advances on earlier digital humans.

We report the availability of a digitized Chinese male and a digitzed Chinese female typical of the population and with no obvious abnormalities. The embalming and milling procedures incorporate three technical improvements over earlier digitized cadavers. Vascular perfusion with coloured gelatin was performed to facilitate blood vessel identification. Embalmed cadavers were embedded in gelatin and cryosectioned whole so as to avoid section loss resulting from cutting the body into smaller pieces. Milling performed at -25 degrees C prevented small structures (e.g. teeth, concha nasalis and articular cartilage) from falling off from the milling surface. The male image set (.tiff images each of 36 Mb) has a section resolution of 3072 x 2048 pixels ( approximately 170 micro m, the accompanying magnetic resonance imaging and computer tomography data have a resolution of 512 x 512, i.e. approximately 440 micro m). The Chinese Visible Human male and female datasets are available at http://www.chinesevisiblehuman.com. (The male is 90.65 Gb and female 131.04 Gb). MPEG videos of direct records of real-time volume rendering are at: http://www.cse.cuhk.edu.hk/~crc

Adult↗
PubMed2004

Tyramine receptor (SER-2) isoforms are involved in the regulation of pharyngeal pumping and foraging behavior in Caenorhabditis elegans.

Octopamine regulates essential processes in nematodes; however, little is known about the physiological role of its precursor, tyramine. In the present study, we have characterized alternatively spliced Caenorhabditis elegans tyramine receptor isoforms (SER-2 and SER-2A) that differ by 23 amino acids within the mid-region of the third intracellular loop. Membranes prepared from cells expressing either SER-2 or SER-2A bind [3H]lysergic acid diethylamide (LSD) in the low nanomolar range and exhibit highest affinity for tyramine. Similarly, both isoforms exhibit nearly identical Ki values for a number of antagonists. In contrast, SER-2A exhibits a significantly lower affinity than SER-2 for other physiologically relevant biogenic amines, including octopamine. Pertussis toxin treatment reduces affinity for both tyramine and octopamine, especially for octopamine in membranes from cells expressing SER-2, suggesting that the conformation of the mid-region of the third intracellular loop is dictated by G-protein interactions and is responsible for the differential tyramine/octopamine affinities of the two isoforms. Tyramine reduces forskolin-stimulated cAMP levels in HEK293 cells expressing either isoform with nearly identical IC50 values. Tyramine, but not octopamine, also elevates Ca2+ levels in cells expressing SER-2 and to a lesser extent SER-2A. Most importantly, ser-2 null mutants (pk1357) fail to suppress head movements while reversing in response to nose-touch, suggesting a role for SER-2 in the regulation of foraging behavior, and fail to respond to tyramine in assays measuring serotonin-dependent pharyngeal pumping. These are the first reported functions for SER-2. These results suggest that C. elegans contains tyramine receptors, that individual SER-2 isoforms may differ significantly in their sensitivity to other physiologically relevant biogenic amines, such as octopamine (OA), and that tyraminergic signaling may be important in the regulation of key processes in nematodes.

Adrenergic Uptake Inhibitors↗
PubMed2004

Expression of lung uncoupling protein-2 mRNA is modulated developmentally and by caloric intake.

Lung expresses a high concentration of uncoupling protein-2 (UCP-2) mRNA, but neither its pulmonary regulation nor function is known. We measured lung UCP-2 mRNA expression in two animal models: in neonatal rats when both the metabolic rate, as measured by oxygen consumption, and levels of serum free fatty acids (FFAs) increase and in adult mice during decreased food intake, when levels of serum FFAs increase but the metabolic rate decreases. In rat lung, the concentration of UCP-2 mRNA was low and unchanged during late gestation, increased approximately twofold within 6 hrs after birth, and, compared with late gestation, remained approximately threefold higher from day 1 to adulthood. The early postnatal rise in the lung UCP-2 mRNA concentration was partially blocked by an antithyroid drug and was increased by treatment with triiodothyronine. Unlike lung, heart UCP-2 mRNA levels were lower during adulthood than at day 15. In adult mice, lung UCP-2 mRNA concentrations increased approximately fivefold within 12 hrs of 67% calorie restriction (CR), remained elevated during 2 weeks of CR, fell to control levels within 24 hrs of refeeding (CR-RF), and positively correlated with serum FFA concentrations. Heart UCP-2 expression during CR and CR-RF was similar to that of lung; liver UCP-2 mRNA levels were slightly lower during CR and returned to control levels during CR-RF. These data suggest that the regulation of UCP-2 is at least partly tissue-specific and that, in the adult mouse, lung UCP-2 is regulated not by oxygen consumption but by FFAs. Moreover, lung UCP-2 mRNA levels in mice fed ad libitum was increased by the intraperitoneal administration of Intralipid, a 20% fat emulsion. On the basis of these data in adult mice, together with the findings of others that levels of FFAs increase by 2 hrs after birth, we propose lung UCP-2 is regulated by FFA.

Animals↗
PubMed2004

Flocculation performance of a novel synthesized flocculant with low ecological risk.

Combined flocculants with low ecological risk are urgently required in water supply and wastewater treatment in China. A novel flocculant was thus developed under the condition of low ecological risk (noted as CAS). The experiments to examine wastewater treatment performance of the new product showed that there was favourable performance in the flocculation process in contrast to commercial flocculants in treating kaolin suspensions, municipal effluent and domestic wastewater. Flocculation performance included the turbidity removal rate, sediment character and a decrease in COD (chemical oxygen demand). The sediment time of flocculation is short and the removal rate of turbidity treated by CAS is high compared with PAC (polyaluminum-chloride), PAM (polyacrylamide) and the combined addition of PAC and PAM. The optimal concentration required to affect flocculation processes is dependent on kaolin concentration and the character of the wastewater within the range examined. It also showed that CAS is effective to treat wastewater with high turbidity.

China↗
PubMed2004

[Expression of HSP70 induced by ketamine in the hippocampus of rat at different ages].

OBJECTIVE: This experiment was designed to explore the possible mechanism of the brain injury caused by ketamine. METHODS: Thirty-five adult SD rats randomly divided into a control group and 6 experiment groups were given intrapertioneal injections of normal saline, 20.0, 40.0, 60.0, 80.0, 100.0, 120.0 mg/kg of ketamine respectively. Another 35 SD rats at 0-10, 11-20, 21-30, 31-45, 46-60, 61-90, 91-120 days old were allocated to 7 corresponding age groups and were given intrapertioneal injection of ketamine 80.0 mg/kg. Immunocytochemistry was used to detect HSP70 expression in rat hippocampus, and MIAS-2000 photography analytic software was chosen to analyze HSP70 expression. RESULTS: Ketamine induced HSP70 expression in adult rat hippocampus. Below the dose of 80.0 mg/kg, ketamine induced higher level of HSP70 expression as the dose increased; however, above the dose of 80.0 mg/kg, ketamine induced lower level of HSP70 expression as the dose increased. Ketamine did not induce HSP70 expression in the rats under 20 days of age; it induced the same HSP70 expression in rats of 90 days and over; and analyses of the rats of 20-90 days revealed that the elder the rat is, the higher the HSP70 expression will be. CONCLUSION: Ketamine injures the neurons of rat hippocampus and induces the expression of HSP70, and the higher the dose is given, the more serious the injury is seen; and ketamine induces higher level of HSP70 expression in adult rats than in infant rats.

Age Factors↗
PubMed2004

[Improved laparoscopic Vechitti procedure for constructing a functioning vagina].

OBJECTIVE: To investigate the clinical effect of improved laparoscopic Vechitti procedure for constructing a functioning vagina. METHODS: By using the method of raising vestibular mucosa, 18 patients with congenital absence of vagina and uterus underwent surgery in our hospital. No cave was made between bladder and rectum. The procedure involved puncturing the vulvar vestibulum pit with an epidural paracentetic needle or specially-made needle into abdominal cavity through rectovesical interspace, two drag-lines was introduced through anterior abdominal wall, using the line to tie a clothes button of 2.0-2.5 cm diameter to the vulva, rasing the lines day by day, the vestibule go upward along with the button, then the vagina was formed. RESULTS: After the procedures, the artificial vagina of all 18 patients could hold a speculum and the mucosa appeared soft and smooth with normal lubrication. The vulvar tissues appeared uninjured and normal in all cases. The married patients were satisfactory to the intercourse. One case of vagino-rectal fistula was observed in a patient after she rode a bicycle with the vaginal mould. CONCLUSION: The improved laparoscopic Vechitti procedure for constructing a functioning vagina has less trauma than conventional operation and is easy to operate. Therefore, the new improved procedure is a preferred way in constructing vagina for treating those patients.

Adult↗
PubMed2003

U1A RNA-binding domain at 1.8 A resolution.

The human U1A RNA-binding domain (RBD1) adopts one of the most common protein folds, the RNA-recognition motif, and is a paradigm for understanding RNA-protein interactions. A 2.8 A resolution structure of the unbound RBD1 has previously been determined [Nagai et al. (1990). Nature (London), 348, 515-520] and revealed a well defined alpha/beta core with disordered termini. Using a longer construct, a 1.8 A resolution structure of the unbound domain was determined that reveals an ordered C-terminal helix. The presence of this helix is consistent with a solution structure of the free domain [Avis et al. (1996). J. Mol. Biol. 257, 398-411]; however, in the solution structure the helix occludes the RNA-binding surface. In the present structure, the helix occupies a position similar to that seen in a 1.9 A resolution RNA-RBD1 complex structure [Oubridge et al. (1994). Nature (London), 372, 432-438]. The crystals in this study were grown from 2.2 M sodium malonate. It is possible that the high salt concentration helps to orient the C-terminal helix in the RNA-bound conformation by strengthening hydrophobic interactions between the buried face of the helix and the alpha/beta core of the protein. Alternatively, the malonate (several molecules of which are bound in the vicinity of the RNA-binding surface) may mimic RNA.

Amino Acid Motifs↗
PubMed2003

A novel estrogen receptor ligand template.

Three synthetic routes towards a novel estrogen receptor ligand template based on a rigid bicyclo-[3.3.1]-nonene core have been investigated. The prototype compound exhibits potent binding at the ERbeta receptor and promising estrogen receptor subtype selectivity.

Alkenes↗
PubMed2003

[The analysis of S gene phylogenetic tree of HBV in transmission from father to infant].

OBJECTIVE: To study HBV transmission from father to infants, the study was carried out. METHODS: The study contained 16 pairs of fathers who was HBV carriers, and infants whose mothers wasn't HBV carriers. The infants infected HBV in womb. The homogenous of HBV S gene were compared between fathers and infants, meanwhile HBV gene phylogenetic tree were analyzed. RESULTS: The genotype of 16 pairs fathers and infants were HBV adw. The homogenous of HBV S gene were 98% approximately 100%. The mutation of 488, 491, 494, 530, 531, 546, 581, 621 nucleotide of HBV S gene caused in 112, 113, 114, 126, 131, 143, 156 amino acid substitution. The mutation of 126 amino acid from Threonine to Alanine didn't existed in the gene bank. The sequence was difference from gene classification. CONCLUSION: The homogenous of HBV S gene of fathers and infants was very high. The HBV gene characteristic in China was difference from gene bank.

Adult↗
PubMed2003

Creation of the Chinese visible human data set.

The United States Visible Human Project (VHP) created a digital image data set of complete human male (data acquisition finished in November 1994) and female (data acquisition finished in December 1995) cadavers in magnetic resonance imaging (MRI), computed tomography (CT), and anatomical (anatomic serial section) modes. VHP aroused worldwide enthusiasm for Visible Human Research (VHR), and the data set is being used in a variety of research and educational domains. The Visible Korean Human (VKH) male was produced in March 2001. To accelerate worldwide VHR and to promote virtual anatomy as a revolutionary break with conventional anatomy, more visible human data sets representative of different populations of the world are in demand. The Chinese Visible Human (CVH) male (created in October 2002) and female (created in February 2003) project achieved greater integrity of images, easier blood vessel identification, and were free of organic lesion (unlike the other visible human projects). We performed data acquisition, three-dimensional (3D) reconstruction, and visualization with improved technology to create CVH male and female. CVH is the first volumetric data representing a complete normal adult human male and female of an Asian population. This article presents the history of Chinese Visible Human cadavers and the methods and technology used to produce the data set.

Anatomy, Cross-Sectional↗