Biomedical subjects

J Ni

Publications and source records attributed to J Ni.

At least 19 recordsLinked to original sources

PubMed2006

Direct electrochemistry of glucose oxidase immobilized on a hexagonal mesoporous silica-MCM-41 matrix.

The direct electrochemistry of glucose oxidase (GOD) immobilized on a hexagonal mesoporous silica modified glassy carbon electrode was investigated. The adsorbed GOD displayed a pair of redox peaks with a formal potential of -417 mV in 0.1 M pH 6.1 phosphate buffer solution (PBS). The response showed a diffusion-controlled electrode process with a two-electron transfer coupled with a two-proton transfer reaction process. GOD immobilized on a hexagonal mesoporous silica retained its bioactivity and stability. In addition, the immobilized GOD could electrocatalyze the oxidation of glucose to gluconlactone by taking ferrocene monocarboxylic acid (FMCA) as a mediator in N(2) saturated solutions, indicating that the electrode may have the potential application in biosensors to analyze glucose. The sensor could exclude the interference of commonly coexisted uric acid, p-acetaminophenol and ascorbic acid and diagnose diabetes very fast and sensitively. This work demonstrated that the mesoporous silica provided a novel matrix for protein immobilization and the construction of biosensors.

Biosensing Techniques↗

PubMed2006

Puerarin injection for unstable angina pectoris.

BACKGROUND: Puerarin is extracted from the Chinese herb puerariae lobata. Many users of Chinese herbal medicine believe that puerarin has positive effects in the treatment of coronary heart disease (CHD). In recent years puerarin injection has been widely used to treat CHD and angina pectoris. OBJECTIVES: To assess the benefits and harms of puerarin injection for unstable angina. SEARCH STRATEGY: The following electronic databases were searched: The Cochrane Controlled Trials Register on The Cochrane Library (Issue 3, 2004), MEDLINE (1995 to 2004), EMBASE (1995 to 2004), CBM (1995 to 2004), Chinese Cochrane Centre Controlled Trials Register (to 2004), Current Controlled Trials (www.controlled-trials.com) and The National Research Register. We also hand searched 60 Chinese traditional medicine journals. SELECTION CRITERIA: Randomised controlled trials undertaken on adults with unstable angina evaluating the following types of interventions: Puerarin injection compared to western drugs or placebo, or puerarin injection used with western drugs compared to western drugs alone. DATA COLLECTION AND ANALYSIS: Data were extracted and analysed independently by two reviewers. Differences in data extraction and analysis were resolved by consensus, referring back to the original article. Study authors were contacted for additional information. Adverse effects information was collected from the trials. MAIN RESULTS: 20 trials involving 1240 people were included. All trials identified were classified as having a high risk of bias because of poor reported methodology. The duration of treatment was 7-20 days and no information supplied suggested longer follow-ups were conducted for any trials. This limited the observation to participants who were not undertaking normal activities of daily living. The primary outcome (death) was not report in any trial. For all the secondary outcome measures, frequency of acute angina attacks, improvements in ECG, doses and incidence of nitroglycerine needed and levels of plasma endothelin, there was no evidence that puerarin had better or worse effects to other conventional treatments. There was strong evidence to suggest that puerarin injection plus western drugs was a better treatment option than western drugs alone. AUTHORS' CONCLUSIONS: Puerarin injection may be effective in unstable angina when used in addition to conventional treatments. However, these finding should be interpreted with care because of the very low methodological quality of studies and potential publication bias. In the light of the findings, a more rigorously designed, randomised double-blind placebo-controlled trial is needed.

Adult↗

PubMed2006

LIGHT induces differentiation of mouse embryonic stem cells associated with activation of ERK5.

LT-related inducible ligand that competes for glycoprotein D binding to herpesvirus entry mediator on T cells (LIGHT) is a recently cloned type II transmembrane protein belonging to the TNF family that was originally identified as a weak inducer of apoptosis. This cytokine has been extensively defined in its role on T-cell regulation and dendritic cell maturation. However, whether this cytokine regulates stem cell proliferation and/or differentiation remains unknown. In this study, we transduced exogenous LIGHT into embryonic stem cells (ES cells) and found it induced their differentiation. The expression of phospho-STAT3, Nanog and Oct-4 was reduced in LIGHT-transduced ES cells compared with wild-type ES cells. LIGHT-transduced ES cells exhibit a low level of SSEA-1 surface antigen and alkaline phosphatase staining compared with wild-type cells. Introduction of LIGHT into ES cells results in the dephosphorylation of MKP-3 and activation of extracellular signal-regulated kinase (ERK)5. When ERK5 was inhibited by the specific inhibitor PD184352 or knocked down by ERK5 siRNA, reduction of Oct-4 and SSEA-1 expression was rescued. We conclude that LIGHT overrides Leukemia inhibitory factor to induce ES cell differentiation associated with activation of ERK5.

Animals↗

PubMed2006

Aquaporin-1 plays an essential role in water permeability and ultrafiltration during peritoneal dialysis.

The water channel aquaporin-1 (AQP1) is considered as the molecular counterpart of the ultrasmall pore predicted by the three-pore model of fluid transport across the peritoneal membrane. However, the definitive proof of the implication of AQP1 in solute-free water transport, sodium sieving, and ultrafiltration (UF) during peritoneal dialysis (PD) is lacking, and the effects of its deletion on the structure of the membrane are unknown. Using real-time reverse transcriptase-polymerase chain reaction and immunogold electron microscopy, we showed that AQP1 is the most abundant member of the AQP gene family expressed in the mouse peritoneum, and the only one located in the capillary endothelium. Transport studies during a 2-h dwell demonstrated that, in comparison with Aqp1(+/+) littermates, Aqp1(-/-) mice had no sodium sieving; an approximately 70% decrease in the initial, solute-free UF; and an approximately 50% decrease in cumulative UF. These modifications occurred despite unchanged osmotic gradient and transport of small solutes in the Aqp1(-/-) mice. Heterozygous Aqp1(+/-) mice showed intermediate values in sodium sieving and initial UF, whereas cumulative UF was similar to Aqp1(+/+) mice. The deletion of AQP1 had no effect on the expression of other AQPs and on the density, structure, or diameter of peritoneal capillaries. These data provide direct evidence for the role of AQP1 during PD. They validate essential predictions of the three-pore model: (i) the ultrasmall pores account for the sodium sieving, and (ii) they mediate 50% of UF during a hypertonic dwell.

Animals↗

PubMed2005

Vitamin A for non-measles pneumonia in children.

BACKGROUND: Acute respiratory infections, mostly in the form of pneumonia, are the leading causes of death in children under five years of age in developing countries. Some clinical trials have demonstrated that vitamin A supplementation reduces the severity of respiratory infection and mortality in children with measles. OBJECTIVES: To determine whether adjunctive vitamin A is effective in infants and children diagnosed with non-measles pneumonia. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2004); MEDLINE (1996 to November Week 3, 2004); EMBASE (1990 to September 2004); LILACS (9 January 2004); CINAHL (1990 to November 2004); Biological Abstracts (1990 to November 2004) and Current Contents (1990 to September 2004); and the Chinese Biomedicine Database (CBM) (1994 to November 2004). SELECTION CRITERIA: Only parallel-arm, randomised and quasi-randomised controlled trials in which children (younger than 15 years old) with non-measles pneumonia were treated with adjunctive vitamin A were included. DATA COLLECTION AND ANALYSIS: Two authors independently extracted data and assessed trial quality. Study authors were contacted for additional information. MAIN RESULTS: Five trials involving 1453 infants and children were included. There was no significant reduction in the mortality associated with pneumonia in children treated with vitamin A compared to those who were not (pooled odds ratio (OR) 1.49; 95% confidence interval (CI) 0.66 to 3.35). In addition, there was a lack of a statistically significant effect on duration of stay in hospital (weighted mean difference (WMD) 0.08; 95% CI -0.43 to 0.59). Vitamin A was associated with a 39% reduction in antibiotic firstline failure (OR 0.65; 95% CI 0.42 to 1.01). Children receiving vitamin A were no more likely to experience vomiting (OR 0.77; 95% CI 0.45 to 1.33), diarrhoea (OR 0.57; 95% CI 0.31 to 1.05), bulging of the fontanelles (OR 8.25; 95% CI 0.44 to 155.37) or irritability (OR 0.93, 95% CI 0.56 to 1.57) than those not receiving vitamin A. There was no statistical significance between vitamin A and placebo groups (OR 0.90; 95% CI -1.10 to 2.90) in chest x-ray results. Disease severity after supplementary high-dose vitamin A was significantly worse in children who received vitamin A compared with placebo. Low-dose vitamin A was associated with a significant reduction in the recurrent rate of bronchopneumonia (OR 0.12; 95% CI 0.03 to 0.46). AUTHORS' CONCLUSIONS: The evidence did not suggest a significant reduction with vitamin A adjunctive treatment in mortality, measures of morbidity, nor an effect on the clinical course of pneumonia in children with non-measles pneumonia. However, not all studies measured all outcomes, limiting the number of studies that could be incorporated into the meta-analyses, so that there may have been a lack of statistical power to detect statistically significant differences.

Child↗

PubMed2005

Chinese medicinal herbs for influenza.

BACKGROUND: Influenza is an acute respiratory communicable disease which can cause high morbidity and mortality in an epidemic. Traditional Chinese medicinal herbs following a particular theory may be a potential medicine of choice. OBJECTIVES: The objective of this review was to assess the therapeutic effect and adverse reaction of Traditional Chinese medicinal herbs in treating uncomplicated influenza. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2004); MEDLINE (January 1966 to October 2004); EMBASE (January 1988 to October 2004); CBM (Chinese Biomedical Database) (January 1980 to December 2003); and the Chinese Cochrane Center's Controlled Trials Register (up to December 2003). We also searched Current Controlled Trials (www.controlled-trials.com) and the National Research Register (http://www.update-software.com/National/) for ongoing trials and reference lists of articles. We wrote to researchers in the field, or authors of studies evaluated in the review for more information. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing traditional Chinese medicinal herbs with placebo, or various other Chinese medicinal herbs, or with other current regimes normally used in care or comparing drugs with herbal preparations to simple drugs in treating defined uncomplicated influenza patients. DATA COLLECTION AND ANALYSIS: At least two reviewers extracted data and assessed trial quality. MAIN RESULTS: Eleven studies with the number of participants ranged from 52 to 479. In total 2,088 participants were included in the review. As the interventions of the included studies were different from each other and most of the studies were of low quality, we did not perform a summary meta-analysis. Some of the studies showed positive results favouring Traditional Chinese medicinal herb treatment compared to antiviral or antipyretic-analgesic drugs or the combination of them. Only three studies mentioned adverse reactions but no detailed data were acquired in the included studies. Eleven studies with the number of participants ranged from 52 to 479, 2,088 in total were included. As the interventions of the included studies were different from each other and most of the studies were of low quality, we failed to perform a summary meta-analysis. Some of the studies showed positive results favouring Traditional Chinese medicinal herb treatment compared to antiviral or antipyretic-analgesic drugs or the combination of them. Only three studies mentioned adverse reactions but no detailed data was acquired in the included studies. AUTHORS' CONCLUSIONS: The small number of included studies and participants, as well as the low quality of most studies, made the evidence far from conclusive for clinical decision making, although traditional Chinese medicinal herbs as a whole seem to be comparatively or more effective compared to different chemical drugs. A certain herbal preparation could not be recommended for there was not enough evidence. More high quality randomised controlled trials (RCTs) with similar interventions are required to strengthen the evidence for the efficacy and safety of certain herbal preparation.

Drugs, Chinese Herbal↗

PubMed2004

Expression of Smad2 and Smad4 in mouse uterus during the oestrous cycle and early pregnancy.

SMAD2 and SMAD4 are intracellular transducers of TGF-beta superfamily. In situ hybridization and semi-quantitative RT-PCR were employed to determine the temporal and spatial expression of Smad2 and Smad4 mRNA in mouse uterus during the oestrous cycle and early pregnancy. Smad2 mRNA was predominantly present in the luminal and glandular epithelium at dioestrus and prooestrus, while Smad4 expression was at a steady level in the luminal and glandular epithelium throughout the oestrous cycle. During pre-implantation period, Smad2 hybridization signals were accumulated in the luminal and glandular epithelium at a basal level; Smad4 mRNA appeared in the epithelium with a little variation in hybridization signal intensity. After implantation, on day 5 of pregnancy, Smad2 signals were localized to the subluminal stroma surrounding the implanting blastocyst, and Smad4 mRNA were accumulated in the decidua near the luminal epithelium. Both Smads were present in the decidua on days 6-7 with a switch from the mesometrial pole to the antimesometrial pole. RT-PCR results showed that both Smad2 and Smad4 mRNA levels were rising during peri-implantatation. The results suggest that Smad2 and Smad4 might be involved in the cycling changes of mouse uterus during the oestrous cycle and embryo implantation.

Animals↗

PubMed2002

Seismic images of crust and upper mantle beneath Tibet: evidence for Eurasian plate subduction.

Seismic data from central Tibet have been combined to image the subsurface structure and understand the evolution of the collision of India and Eurasia. The 410- and 660-kilometer mantle discontinuities are sharply defined, implying a lack of a subducting slab beneath the plateau. The discontinuities appear slightly deeper beneath northern Tibet, implying that the average temperature of the mantle above the transition zone is about 300 degrees C hotter in the north than in the south. There is a prominent south-dipping converter in the uppermost mantle beneath northern Tibet that might represent the top of the Eurasian mantle lithosphere underthrusting the northern margin of the plateau.

Journal Article↗

PubMed2001

Analysis of terpene compounds in Cimicifuga foetida L. by reversed-phase high-performance liquid chromatography with evaporative light scattering detection.

An RP-HPLC method with evaporative light scattering detection (ELSD) was developed for the analysis of terpene compounds in traditional Chinese medicine. Actein, 27-deoxyactein and cimicifugoside in a typical Chinese medicine of Cimicifuga foetida L. were quantitatively analyzed. Comparing ELSD with UV detection under the same eluent conditions, the former showed better sensitivity and a more stable baseline. The ELSD responses versus sample size of three terpenes and those in double logarithmic were investigated. The good calibration curves in double logarithmic coordinator for actein, 27-deoxyactein and cimicifugoside were obtained. Three solutions for the extraction of the terpene compounds were also compared, the results indicated that methanol-water (80:20) is the best among them. The method was applied to quantify actein, 27-deoxyactein and cimicifugoside in Cimicifuga foetida L. from Hunan, China. It was shown that ELSD is an effective detection method for the analysis of the non-volatile terpenes in traditional Chinese medicine.

Calibration↗

PubMed2001

Capillary electrochromatography for separation of peptides driven with electrophoretic mobility on monolithic column.

A mode of capillary electrochromatography for separation of ionic compounds driven by electrophoretic mobility on a neutrally hydrophobic monolithic column was developed. The monolithic column was prepared from the in situ copolymerization of lauryl methacrylate and ethylene dimethacrylate to form a C12 hydrophobic stationary phase. It was found that EOF in this hydrophobic monolithic column was very poor, even the pH value of mobile phase at 8.0. The peptides at acidic buffer were separated on the basis of their differences in electrophoretic mobility and hydrophobic interaction with the stationary phase; therefore, different separation selectivity can be obtained in CEC from that in capillary zone electrophoresis (CZE). Separation of peptides has been realized with high column efficiency (up to 150,000 plates/meter) and good reproducibility (migration time with RSD <0.5%), and all of the peptides, including some basic peptides, showed good peak symmetry. Effects of the mobile phase compositions on the retention of peptides at low pH have been investigated in a hydrophobic capillary monolithic column. The significant difference in selectivity of peptides in CZE and CEC has been observed. Some peptide isomers that cannot be separated by CZE have been successfully separated on the capillary monolithic column in this mode with the same buffer used.

Chromatography, Micellar Electrokinetic Capillary↗

PubMed2001

Exposure-response relationship between paternal smoking and children's pulmonary function.

We conducted a cross-sectional study to investigate paternal smoking and children's pulmonary function in rural communities of Anqing, China. Our analysis included 1,718 children 8 to 15 yr of age whose mothers were never-smokers. Multiple linear regression models were used to estimate the effect of paternal smoking on children's pulmonary function, with adjustment for children's age, sex, weight, height, square of height, asthma, and father's education. When compared with children of never-smoking fathers, children of smoking fathers had small, but detectable deficits in FEV(1) (-36 ml, SE = 20) and FVC (-37 ml, SE = 22). When children of smoking fathers were subdivided into two subgroups, father smoked < 30 cigarettes/day and >/= 30 cigarettes/day, we found that children whose fathers smoked >/= 30 cigarettes/day had the largest deficits in both FEV(1) (-79 ml, SE = 30) and FVC (-71 ml, SE = 34). This monotonic exposure-response relationship remained in all strata when we further stratified our analysis by children's sex and asthma status. Our data also suggested that the relationship was greatest among nonasthmatic girls, although neither sex nor asthma interaction terms were statistically significant. We conclude that there is a monotonic exposure-response relationship between paternal smoking and decline of pulmonary function in children in this rural Chinese population.

Adolescent↗

PubMed2001

A selenium-containing catalytic antibody with Type I deiodinase activity.

Acting as a mimic of type I deiodinase (DI), a selenium-containing catalytic antibody (Se-4C5) prepared by converting the serine residues of monoclonal antibody 4C5 raised against thyroxine (T4) into selenocysteines, can catalyze the deiodination of T(4) to 3,5,3'-triiodothyronine (T(3)) with dithiothreitol (DTT) as cosubstrate. Investigations into the deiodinative reaction by Se-4C5 revealed the relationship between the initial velocity and substrate concentration was subjected to Michaelis-Menten equation and the reaction mechanism was ping-pong one. The kinetic properties of the catalytic antibody were a little similar to those of DI, with Km values for T(4) and DTT of approximately 0.8 microM and 1.8 mM, respectively, and V(m) value of 270 pmol per mg protein per min. The activity could be sensitively inhibited by PTU with a Ki value of approximately 120 microM at 2.0 microM of T(4) concentration, revealing that PTU was a competitive inhibitor for DTT.

Amino Acid Substitution↗

PubMed2001

Association of viral genome with graft loss in children after cardiac transplantation.

BACKGROUND: The survival of recipients of cardiac allografts is limited by rejection, lymphoproliferative disease, and coronary vasculopathy. The purpose of this study in children who had received heart transplants was to evaluate the cardiac allografts for myocardial viral infections and to determine whether the presence of viral genome in the myocardium correlates with rejection, coronary vasculopathy, or graft loss. METHODS: We enrolled heart-transplant recipients 1 day to 18 years old who were undergoing evaluation for possible rejection and coronary vasculopathy. Endomyocardial-biopsy specimens were evaluated for evidence of rejection with the use of standard criteria and were analyzed for the presence of virus by the polymerase chain reaction (PCR). RESULTS: PCR analyses were performed on 553 consecutive biopsy samples from 149 transplant recipients. Viral genome was amplified from 48 samples (8.7 percent) from 34 patients (23 percent); adenovirus was found in 30 samples, enterovirus in 9 samples, parvovirus in 5 samples, cytomegalovirus in 2 samples, herpes simplex virus in 1 sample, and Epstein-Barr virus in 1 sample. In 29 of the 34 patients with positive results on PCR (85 percent), an adverse cardiac event occurred within three months after the positive biopsy, and 9 of the 34 patients had graft loss due to coronary vasculopathy, chronic graft failure, or acute rejection. In 39 of the 115 patients with negative results on PCR (34 percent), an adverse cardiac event occurred within three months of the negative PCR finding; graft loss did not occur in any of the patients in this group. The odds of graft loss were 6.5 times as great among those with positive results on PCR (P=0.006). The detection of adenovirus was associated with considerably reduced graft survival (P=0.002). CONCLUSIONS: Identification of viral genome, particularly adenovirus, in the myocardium of pediatric transplant recipients is predictive of adverse clinical events, including coronary vasculopathy and graft loss.

Adenoviridae↗

PubMed2001

Preparation and properties of a selenium-containing catalytic antibody as type I deiodinase mimic.

Conversion of thyroxine (T4) to 3,5,3'-triiodothyronine is an essential first step in controlling thyroid hormone action. Type I deiodinase (DI) can catalyze the conversion to produce the bulk of serum 3,5,3'-triiodothyronine. Acting as a mimic of DI, a selenium-containing catalytic antibody (Se-4C5) prepared by converting the serine residues of monoclonal antibody 4C5 raised against T4 into selenocysteines, can catalyze the deiodination of T4 with dithiothreitol (DTT) as cosubstrate. The mimic enzyme Se-4C5 exhibited a much greater deiodinase activity than model compound ebselen and another selenium-containing antibody Se-Hp4 against GSH. The coupling of selenocysteine with the combining pocket of antibody 4C5 endowed Se-4C5 with enzymatic activity. To probe the catalytic mechanism of the catalytic antibody, detailed kinetic studies were carried out in this paper. Investigations into the deiodinative reaction revealed the relationship between the initial velocity and substrate concentration. The characteristic parallel Dalziel plots demonstrated that Se-4C5-catalyzed reaction mechanism was ping-pong one, involving at least one covalent enzyme intermediate. The kinetic properties of the catalytic antibody were similar to those of DI, with Km values for T4 and DTT of approximately 0.8 microm and 1.8 mm, respectively, and a Vm value of 270 pmol per mg of protein per min. The activity could be sensitively inhibited by 6-propyl-2-thiouracil (PTU) with a K(i) value of approximately 120 microm at 2.0 microm T4 concentration. The PTU inhibition was progressively alleviated with the increasing concentration of added DTT, revealing that PTU was a competitive inhibitor for DTT.

Animals↗

PubMed2001

RELT, a new member of the tumor necrosis factor receptor superfamily, is selectively expressed in hematopoietic tissues and activates transcription factor NF-kappaB.

The members of tumor necrosis factor receptor (TNFR) superfamily have been designated as the "guardians of the immune system" due to their roles in immune cell proliferation, differentiation, activation, and death (apoptosis). This study reports the cloning of a new member of the TNFR superfamily, RELT (Receptor Expressed in Lymphoid Tissues). RELT is a type I transmembrane glycoprotein with a cysteine-rich extracellular domain, possessing significant homology to other members of the TNFR superfamily, especially TNFRSF19, DR3, OX40, and LTbeta receptor. The messenger RNA of RELT is especially abundant in hematologic tissues such as spleen, lymph node, and peripheral blood leukocytes as well as in leukemias and lymphomas. RELT is able to activate the NF-kappaB pathway and selectively binds tumor necrosis factor receptor-associated factor 1. Although the soluble form of RELT fusion protein does not inhibit the one-way mixed lymphocyte reaction, immobilized RELT is capable of costimulating T-cell proliferation in the presence of CD3 signaling. These results define a new member of the TNFR superfamily that may be a potential regulator of immune responses.

Amino Acid Sequence↗

PubMed2001

Identification, characterization and leucocyte expression of Siglec-10, a novel human sialic acid-binding receptor.

Here we characterize Siglec-10 as a new member of the Siglec family of sialic acid-binding Ig-like lectins. A full-length cDNA was isolated from a human spleen library and the corresponding gene identified. Siglec-10 is predicted to contain five extracellular Ig-like domains and a cytoplasmic tail containing three putative tyrosine-based signalling motifs. Siglec-10 exhibited a high degree of sequence similarity to CD33-related Siglecs and mapped to the same region, on chromosome 19q13.3. The expressed protein was able to mediate sialic acid-dependent binding to human erythrocytes and soluble sialoglycoconjugates. Using specific antibodies, Siglec-10 was detected on subsets of human leucocytes including eosinophils, monocytes and a minor population of natural killer-like cells. The molecular properties and expression pattern suggest that Siglec-10 may function as an inhibitory receptor within the innate immune system.

Amino Acid Sequence↗

PubMed2001

Cell cycle regulation by galectin-12, a new member of the galectin superfamily.

Galectins are a family of beta-galactoside-binding animal lectins with conserved carbohydrate recognition domains (CRDs). Here we report the identification and characterization of a new galectin, galectin-12, which contains two domains that are homologous to the galectin CRD. The N-terminal domain contains all of the sequence elements predicted to form the two beta-sheets found in other galectins, as well as conserved carbohydrate-interacting residues. The C-terminal domain shows considerable divergence from the consensus sequence, and many of these conserved residues are not present. Nevertheless, the protein has lactose binding activity, most likely due to the contribution of the N-terminal domain. The mRNA for galectin-12 contains features coding for proteins with growth-regulatory functions. These include start codons in a context that are suboptimal for translation initiation and AU-rich motifs in the 3'-untranslated region, which are known to confer instability to mRNA. Galectin-12 mRNA is sparingly expressed or undetectable in many tissues and cell lines tested, but it is up-regulated in cells synchronized at the G(1) phase or the G(1)/S boundary of the cell cycle. Ectopic expression of galectin-12 in cancer cells causes cell cycle arrest at the G(1) phase and cell growth suppression. We conclude that galectin-12 is a novel regulator of cellular homeostasis.

Amino Acid Sequence↗

PubMed2001

Electrochemically actuated mercury pump for fluid flow and delivery.

This paper describes the development of a prototype pumping system with the potential for incorporation into miniaturized, fluid-based analytical instruments. The approach exploits the well-established electrocapillarity phenomena at a mercury/electrolyte interface as the mechanism for pump actuation. That is, electrochemically induced changes in the surface tension of mercury result in the pistonlike movement of a mercury column confined within a capillary. We present herein theoretical and experimental assessments of pump performance. The design and construction of the pump are detailed, and the potential attributes of this design, including the generated pumping pressure, flow rate, and power consumption, are discussed. The possible miniaturization of the pump for use as a field-deployable, fluid-delivery device is also briefly examined.

Electrochemistry↗