Biomedical subjects

X Zhang

Publications and source records attributed to X Zhang.

At least 91 records · Page 5Linked to original sources

PubMed2005

Combination of inhaled long-acting beta2-agonists and inhaled steroids versus higher dose of inhaled steroids in children and adults with persistent asthma.

BACKGROUND: In asthmatic patients inadequately controlled on inhaled corticosteroids and/or those with moderate persistent asthma, two main options are recommended: the combination of a long-acting inhaled beta2 agonist (LABA) with inhaled corticosteroids (ICS) or use of a higher dose of inhaled corticosteroids. OBJECTIVES: To determine, in asthmatic patients, the effect of the combination of long-acting beta2 agonists and inhaled corticosteroids compared to a higher dose of inhaled corticosteroids on the incidence of asthma exacerbations, on pulmonary function and on other measures of asthma control and to look for characteristics associated with greater benefit for either treatment option. SEARCH STRATEGY: We identified randomized controlled trials (RCTs) through electronic database searches (MEDLINE, EMBASE and CINAHL), bibliographies of RCTs and correspondence with manufacturers until April 2004. SELECTION CRITERIA: RCTs were included that compared the combination of inhaled LABA and ICS to a higher dose of inhaled corticosteroids, in children aged 2 years and older, and in adults with asthma. DATA COLLECTION AND ANALYSIS: Studies were assessed independently by two authors for methodological quality and data extraction. Confirmation was obtained from the trialists when possible. The primary endpoint was rate of patients experiencing one or more asthma exacerbations requiring oral corticosteroids. Secondary endpoints included pulmonary function tests (PFTs), symptoms, use of rescue beta2 agonists, adverse events and withdrawal rates. The meta-analysis was done with RevMan Analyses and the meta-regression, with Stata. MAIN RESULTS: Of 593 citations identified, 30 (three pediatric; 27 adult) trials were analysed recruiting 9509 participants, including one study providing two control-intervention comparisons. Only one trial included corticosteroid-naive patients. Participants were symptomatic, generally (N=20 trials) presenting with moderate (FEV1 60-79% of predicted) rather than mild airway obstruction. Trials tested the combination of salmeterol (N=22) or formoterol (N=8) with a median of 400 mcg of beclomethasone or equivalent (BDP-eq) compared to a median of 800 to 1000 mcg/day of BDP-eq. Trial duration was 24 weeks or less in all but four trials. There was no significant group difference in the rate of patients with exacerbations requiring systemic corticosteroids [N=15, RR=0.88 (95% CI: 0.77, 1.02)]. The combination of LABA and ICS resulted in greater improvement from baseline in FEV1 [N=7, WMD=0.10 L (95% CI: 0.07, 0.12)], in symptom-free days [N=8 , WMD=11.90% (95% CI:7.37, 16.44), random effects model], and in the daytime use of rescue beta2 agonists than a higher dose of ICS [N=4, WMD= -0.99 puffs/day (95% CI: -1.41, -0.58), random effects model]. There was no significant group difference in the rate of overall adverse events [N=15, RR=0.93 (95% CI: 0.84, 1.03), random effects model], or specific side effects, with the exception of a three-fold increase rate of tremor in the LABA group [N= 10, RR=2.96 (95%CI: 1.60, 5.45)]. The rate of withdrawals due to poor asthma control favoured the combination of LABA and ICS [N=20, RR=0.69 (95%CI: 0.52, 0.93)]. AUTHORS' CONCLUSIONS: In adult asthmatics, there was no significant difference between the combination of LABA and ICS and a higher dose of ICS for the prevention of exacerbations requiring systemic corticosteroids. Overall, the combination therapy led to greater improvement in lung function, symptoms and use of rescue beta2 agonists, (although most of the results are from trials of up to 24 weeks duration). There were less withdrawals due to poor asthma control in this group than when using a higher dose of inhaled corticosteroids. Apart from an increased rate of tremor, the two options appear safe although adverse effects associated with long-term ICS treatment were seldom monitored.

Administration, Inhalation↗

PubMed2005

Long-acting beta2-agonists versus placebo in addition to inhaled corticosteroids in children and adults with chronic asthma.

BACKGROUND: Long-acting inhaled beta2-adrenergic agonists are recommended as 'add-on' medication to inhaled corticosteroids in the maintenance therapy of asthmatic adults and children aged two years and above. OBJECTIVES: To quantify in asthmatic patients the safety and efficacy of the addition of long-acting beta2-agonists to inhaled corticosteroids on the incidence of asthma exacerbations, pulmonary function and other measures of asthma control. SEARCH STRATEGY: We identified randomised controlled trials (RCTs) through electronic database searches (the Cochrane Airways Group Specialised Register, MEDLINE, EMBASE and CINAHL), bibliographies of RCTs and correspondence with manufacturers, until April 2004. SELECTION CRITERIA: RCTs were included that compared the addition of inhaled long-acting beta2-agonists to corticosteroids with inhaled corticosteroids alone for asthma therapy in children aged two years and above and in adults. DATA COLLECTION AND ANALYSIS: Studies were assessed independently by two review authors for methodological quality and data extraction. Confirmation was obtained from the trialists when possible. The primary endpoint was rate of asthma exacerbations requiring systemic corticosteroids. Secondary endpoints included pulmonary function tests (PFTs), symptom scores, adverse events and withdrawal rates. MAIN RESULTS: Of 594 identified citations, 49 trials met the inclusion criteria: 27 full-text publications, one unpublished full-text report and 21 abstracts. Twenty-three citations (21 abstracts and two full-text publications) provided data in insufficient detail, 26 trials contributed to this systematic review. All but three trials were of high methodological quality. Most interventions (N = 26) were of four-month duration or less. Eight trials focused on children and 18 on adults, with participants generally symptomatic with moderate airway obstruction despite their current inhaled steroid regimen. If a trial had more than one intervention or control group, additional control to intervention comparisons were considered separately. Formoterol (N = 17) or salmeterol (N = 14) were most frequently added to low-dose inhaled corticosteroids (200 to 400 microg/day of beclomethasone (BDP) or equivalent). The addition of a daily long-acting beta2-agonist (LABA) reduced the risk of exacerbations requiring systemic steroids by 19% (relative risk (RR) 0.81, 95% CI 0.73 to 0.90). The number needed to treat for one extra patient to be free from exacerbation for one year was 18 (95% CI 13 to 33). The addition of LABA significantly improved FEV1 (weighted mean difference (WMD) 170 mL, 95% CI 110 to 240) using a random-effects model, increased the proportion of symptom-free days (WMD 17%, 95% CI 12 to 22, N = 6 trials) and rescue-free days (WMD 19%, 95% CI 12 to 26, N = 2 trials). The group treated with LABA plus inhaled corticosteroid showed a reduction in the use of rescue short-acting beta2-agonists (WMD -0.7 puffs/day, 95% CI -1.2 to -0.2), experienced less withdrawals due to poor asthma control (RR 0.5, 95% CI 0.4 to 0.7) and less withdrawals due to any reason (RR 0.9, 95% CI 0.8 to 0.98), using a random-effects model. There was no group difference in risk of overall adverse effects (RR 0.98, 95% CI 0.92 to 1.05), withdrawals due to adverse health events (RR 1.29, 95% CI 0.96 to 1.75) or specific adverse health events. AUTHORS' CONCLUSIONS: In patients who are symptomatic on low to high doses of inhaled corticosteroids, the addition of a long-acting beta2-agonist reduces the rate of exacerbations requiring systemic steroids, improves lung function, symptoms and use of rescue short-acting beta2-agonists. The similar number of serious adverse events and withdrawal rates in both groups provides some indirect evidence of the safety of long-acting beta2-agonists as add-on therapy to inhaled corticosteroids.

Administration, Inhalation↗

PubMed2005

Molecular dynamics simulation studies of the conformation and lateral mobility of a charged adsorbate biomolecule: implications for estimating the critical value of the radius of a pore in porous media.

The conformations, the values of the lateral transport coefficient of a charged biomolecule (desmopressin) in the adsorbed layer and in the liquid layers above the adsorbed layer, the potential energies of the interaction between the biomolecules located in different liquid layers with the charged solid surface and with the biomolecules in the adsorbed layer, the potential energies of the interaction between water molecules in the hydration layers surrounding the conformations of the biomolecules in different layers, as well as the structure and number of hydration layers between the different conformations of desmopressin, were determined by molecular dynamics simulation studies. The results show that the lateral mobility of the adsorbed desmopressin is approximately equal to zero and the value of the lateral transport coefficient of the biomolecule in the liquid layers located above the adsorbed layer increases as the distance of the liquid layer from the charged solid surface increases. But the values of the lateral transport coefficient of the biomolecule in the liquid layers above the adsorbed layer are lower in magnitude than the value of the transport coefficient of desmopressin along the direction normal to the charged solid surface in the liquid phase located above the vacant charged sites of the solid surface, and these differences in the values of the transport coefficients have important implications with respect to the replenishment of the biomolecules in the inner parts of a channel (pore), the overall rate of adsorption, and the form of the constitutive equations that would have to be used in macroscopic models to describe the mechanisms of mass transfer and adsorption in the pores of adsorbent media. Furthermore, a novel method is presented in this work that utilizes the information about the sizes of the conformations of the biomolecule in the adsorbed layer and in the liquid layers above the adsorbed layer along the direction that is normal to the charged solid surface, as well as the number and size of the hydration layers along the same direction, and could be used to estimate the value of the lower bound of the linear characteristic dimension of a pore (i.e., pore radius) in porous adsorbent media (e.g., porous adsorbent particles; skeletons of porous monoliths) in order to realize effective transport and overall adsorption rate.

Adsorption↗

PubMed2005

Endoscopic ultrasound for preoperative staging of esophageal carcinoma.

BACKGROUND: Endoscopic ultrasound (EUS) is potentially the best method for pretreatment staging of esophageal carcinoma once distant metastases have been excluded by other methods. However, its apparent accuracy might be influenced by the use of neoadjuvant therapy. To determine the accuracy of EUS in patients undergoing esophageal resection, the authors reviewed their experience with EUS. METHODS: A total of 73 patients with esophageal carcinoma who underwent an esophagectomy between April 2000 and February 2005 were examined using preoperative EUS and computed tomography (CT). Of these patients, 39 also underwent preoperative neoadjuvant chemoradiotherapy. Both EUS and CT scan were used to determine the depth of tumor penetration (T-stage) and the presence of lymph node metastases (N-stage). These results then were compared with staging determined after pathologic examination of the resected surgical specimen. RESULTS: For patients not undergoing neoadjuvant therapy, T-stage was accurately determined by EUS in 79%, N-stage in 74%, and tumor node metastasis (TNM) classification in 65% of the cases. However, when patients who had undergone neoadjuvant chemoradiotherapy were included, the overall accuracy of EUS was 64% for T-stage, 63% for N-stage, and 53% for TNM classification. For the patients who underwent neoadjuvant therapy, EUS indicated a more advanced T-stage in 49%, N-stage in 38%, and TNM classification in 51% of the cases, as compared with pathology. The overall accuracy of EUS for T- and N-stage carcinomas was superior to that of CT scanning. CONCLUSION: For patients who do not undergo preoperative neoadjuvant chemotherapy and radiotherapy, EUS is a more accurate method for determining T- and N-stage resected esophageal carcinomas. Neoadjuvant therapy, however, results in apparent overstaging, predominantly because of tumor downstaging, and this reduces the apparent accuracy of EUS (and CT scanning) in this patient group. Nevertheless, EUS staging before neoadjuvant therapy could be more accurate than pathologic staging after treatment, thereby providing better initial staging information, which can be used to facilitate treatment.

Adult↗

PubMed2005

Application of an effective method in predicting breakthrough curves of fixed-bed adsorption onto resin adsorbent.

Removal of many organic pollutants including phenolic compounds from industrial wastewater can always be achieved by fixed-bed adsorption onto the polymeric resin adsorbent, and the relevant breakthrough curves would provide much valuable information to help to design a fixed-bed adsorption process in field application. In the present study, a model developed based on the constant-pattern wave approach theory and the Freundlich model was adopted to describe the breakthrough curves of phenol and p-nitrophenol adsorption onto a macroreticular resin adsorbent NDA-100 from aqueous solution. Column experiments were performed at different conditions to verify the model and the results proved that the model would describe the breakthrough curves well. Effect of the operation parameters on breakthrough curves was also discussed to get helpful information in choosing the adsorption process.

Adsorption↗

PubMed2005

137Cs budget during the period of 1960s in a small drainage basin on the Loess Plateau of China.

A sediment profile with a thickness of 28.12 m in a failed reservoir in a small catchment of the Yuntaishan Gully in the Loess Plateau of China consisted of 44 flood couplets deposited during the period from 1960 to 1970 with total volume of 2.36 x 10(6)m(3). Specific sediment yields for a flood event varied from 300 t km(-2) to 14,400 t km(-2) and annual sediment yields varied from 2500 t km(-2) in 1966 to 40,000 t km(-2) in 1964 with a mean value of 12,700 t km(-2)a(-1) for the period. Average annual (137)Cs concentrations of the sediments increased from 0.92 Bq kg(-1) in 1960 to 4.82 Bq kg(-1) in 1963, then decreased to 1.53 Bq kg(-1) in 1970. The total (137)Cs activity in the reservoir sediments was 9.22 x 10(9) Bq, which accounted for 31.9% of the total (137)Cs fallout precipitation of 2.89 x 10(10) Bq within the catchment during the period. The proportion of the (137)Cs loss from the catchment to the (137)Cs fallout precipitation within the catchment in a year varied between 8.01% and 66.8%, and it was 20.9% for the peak (137)Cs deposition year of 1963 and 52.0% in 1964. By analysis of the (137)Cs budget in the catchment for the (137)Cs peak precipitation period from 1962 to 1964, the (137)Cs surface enrichment coefficient Gamma should be much less than 0.23. And for calculation of soil losses on the cultivated land in the inter-gully area by using the Mass Balance Model II, the value of Gamma should be 0.05-0.1.

Cesium Radioisotopes↗

PubMed2005

Expressions and regulation of endothelial and inducible nitric oxide synthases in mouse uterus during the estrous cycle and early pregnancy.

Nitric oxide (NO) has been implicated in many cellular processes. We examined the temporal and spatial expressions of endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) in mouse uteri during the estrous cycle and early pregnancy, as well as the regulation of eNOS and iNOS by estradiol (E2) and progesterone (P4) in ovariectomized mouse uteri using in situ hybridization and immunohistochemistry. Our results showed that positive eNOS and iNOS signals were localized in the uterine luminal epithelium and glandular epithelium during the estrous cycle. In ovariectomized mice, both E2 and P4 regulated the expression of eNOS and iNOS. During early pregnancy, eNOS and iNOS were detected not only in epithelium, but also in the primary decidual zone surrounding implanting embryos on day 6 of pregnancy, and in the whole decidualized stroma on day 7 of pregnancy. In conclusion, the results demonstrated that two NOS isoforms were localized in mouse uteri in specific temporal and spatial patterns during the estrous cycle and early pregnancy, and ovarian hormones can regulate their expression. Furthermore, the data suggest that the expression of NOS during the peri-implantation period might lead to enhance NO production, which could promote embryo implantation.

Animals↗

PubMed2005

Projections of diencephalic dopamine neurons into the spinal cord in mice.

The aim of this study is to investigate the pathway of diencephalic dopaminergic (DA) neuronal innervating into the spinal cord in mice, the pathway is postulated relevant to clinical restless legs syndrome (RLS). Tyrosine hydroxylase (TH) immunohistochemistry was used to identify the DA neuron. The fluorescent tracer Fluoro-Gold (FG) was stereotaxically injected into the T10-L5 spinal cord of CBL57 mice (n=20) seven days before the animals were sacrificed. The diencephalic sections were stained with TH antibody and the FG tracer present in the diencephalic DA neurons were examined under fluoresce microscope. The average number of total DA neurons per side in A11, A12, A13 and A14 was 66+/-8, 221+/-12, 350+/-17 and 254+/-21 respectively. After being injected into the spinal cord, FG reached the DA neurons within the A10 and A11 groups, but didn't target to any other DA neuron groups including the A8 and A9 groups in substantia nigra (SN). The diencephalic A11 DA neurons possessed long axons extending over several segments and possibly traversing the entire length of the spinal cord. It is the first time to report A10 and A11 DA neuron projections into the spinal cord in mice.

Animals↗

PubMed2005

Depth profile of uncompensated spins in an exchange bias system.

We have used the unique spatial sensitivity of polarized neutron and soft x-ray beams in reflection geometry to measure the depth dependence of magnetization across the interface between a ferromagnet and an antiferromagnet. The net uncompensated magnetization near the interface responds to applied field, while uncompensated spins in the antiferromagnet bulk are pinned, thus providing a means to establish exchange bias.

Journal Article↗

PubMed2005

Organochlorines and dioxin-like compounds in green-lipped mussels Perna viridis from Hong Kong mariculture zones.

Concentrations of persistent organic pollutants including polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides and dioxin-like compounds were measured in green-lipped mussels, Perna viridis, collected from seven mariculture zones in Hong Kong between September and October in 2002 in order to evaluate the status, spatial distribution and potential sources of pollution in these areas. Concentrations ranged from 300 to 4400 ng/g lipid weight for total OCs and 170-1000 ng/g lipid weight for total PCBs (based on 28 congeners). Relatively smaller DDT concentrations in mussels compared with previous studies suggest reduced discharges of DDTs from nearby regions into Hong Kong waters. Detection of a mixture of HCH isomers in the mussels indicated that Hong Kong waters were predominantly contaminated by technical HCHs rather than lindane. Mussel samples from all sampling locations elicited significant dioxin-like activity in the H4IIE-luc bioassay. The greatest magnitude of dioxin-like response (39 pg TEQ/g wet wt.) was detected in mussels from Ma Wan in the western waters of Hong Kong, which is strongly influenced by the Pearl River discharge. Human health risk assessment was undertaken to evaluate potential risks associated with the consumption of the green-lipped mussels. Risk quotient (RQ) for dioxin-like compounds was greater than unity suggesting that adverse health effects may be associated with high mussel consumption.

Animals↗

PubMed2005

Multifocal visual evoked potentials to cone specific stimuli in patients with retinitis pigmentosa.

Our aim was to determine whether patients with retinitis pigmentosa show differences in L- and M-cone multifocal visual evoked potential (mfVEP) responses that are eccentricity dependent, as has been shown for control subjects. Second, we compared the losses for mfVEPs to losses on achromatic visual field and multifocal electroretinogram (mfERG) measures in the patients. Monocular mfVEPs were recorded to a pattern reversing display that modulated only the L- or M-cones. Also, standard automated achromatic visual fields and mfERGs were obtained. For the control subjects, the ratio of L-cone to M-cone mfVEP amplitudes increased as a function of retinal eccentricity. For the patients, the ratio did not vary with eccentricity. For all measures, responses were least affected for the first ring (central 2.4 degrees ) and most affected for the third ring (11.6 degrees - 44.4 degrees ). For the first ring, mfERG amplitudes were more impaired than were the mfVEPs or the visual field thresholds. For most of the patients, there was local response correspondence among our measures of visual function.

Adult↗

PubMed2005

A remarkable permeability of canalicular tight junctions might facilitate retrograde, non-viral gene delivery to the liver via the bile duct.

AIMS: To establish the extent of retrograde bile duct infusion at an ultrastructural level, as a preliminary step before evaluating the efficacy of gene delivery to the rat liver via a branch of the bile duct. METHODS: The extent of retrograde infusion into the biliary tree was established by light and electron microscopy, following infusion of 10 nm gold particles into the right lateral lobe. Canalicular permeability was further assessed by the infusion of a 67 kDa protein. For gene delivery, both naked DNA and a synthetic peptide vector system were evaluated. Because canalicular tight junction permeability can be compromised in damaged livers, both normal rats and rats recovering from the hepatotoxin D-galactosamine were studied. RESULTS: The gold particles penetrated the peripheral one third of the hepatic lobules and, surprisingly, reached the space of Disse in normal rats. Equally surprisingly, blood levels of a 67 kDa protein were identical after bile duct infusion and portal vein injection. Gene delivery with peptide/DNA complexes was much more effective in rats treated with D-galactosamine. However, gene delivery with naked DNA was equally effective in normal and damaged livers. Localisation of gene expression showed a scattering of positive hepatocytes restricted to the right lateral lobe. CONCLUSIONS: Retrograde infusion into the bile duct advances well into the hepatic lobule and reveals a remarkable permeability of the canalicular or cholangiole tight junctions in normal rats. It is an effective approach for delivering genes to a small population (approximately 1%) of hepatocytes.

Animals↗

PubMed2005

Adsorption of phenolic compounds from aqueous solution onto a macroporous polymer and its aminated derivative: isotherm analysis.

Adsorption of phenolic compounds from aqueous solution to a macroporous polymeric adsorbent (CHA-111), its animated derivative (MCH-111) and a reference weakly anion exchanger (ND-900) was studied. Experimental results indicated that amino functional groups on the polymeric matrix play an important role in phenol adsorption by MCH-111 and ND-900, which was attributed to the formation of hydrogen bonding between the phenol molecule and the amino group on the polymeric matrix. The semi-empirical Freundlich isotherm equation and its reduced form were employed to interpret the adsorption behavior. A site energy distribution model based on the Polanyi adsorption potential theory can elucidate the adsorption mechanism reasonably.

Adsorption↗

PubMed2005

Modification of polysulfone membranes with polyethylene glycol and lignosulfate: electrical characterization by impedance spectroscopy measurements.

Two sets of composite membranes having an asymmetric sulfonated polysulfone membrane as support layer have been obtained and electrically characterized (membranes SPS-PEG and PA-LIGS). The skin layer of the membrane SPS-PEG contains different percentages of polyethylene glycol in the casting solution (5, 25, 40, and 60 wt%), while lignosulfonate was used for manufacturing PA-LIGS membranes (5, 10, 20, and 40 wt%). Membrane electrical characterization was done by means of impedance spectroscopy (IS) measurements, which were carried out with the membranes in contact with NaCl solutions at different concentrations (10(-3) < or = c(M) < or = 5x10(-2)). Electrical resistance and equivalent capacitance of the different membrane samples were determined from IS plots by using equivalent circuits as models. Results show a clear decrease in the membrane electrical resistance as a result of both polysulfone sulfonation and the increase of the concentration of modifying substances, although a kind of limit concentration was obtained for both polyethylene glycol and lignosulfonate (40 and 20%, respectively). Results also show a decrease of around 90% in electrical resistance due to polysulfone sulfonation, while the value of the dielectric constant (hydrated state) clearly increases.

Electric Impedance↗

PubMed2005

Long-term non-pharmacologic weight loss interventions for adults with type 2 diabetes.

BACKGROUND: Most persons with type 2 diabetes are overweight and obesity worsens the metabolic and physiologic abnormalities associated with diabetes. OBJECTIVES: The objective of this review is to assess the effectiveness of lifestyle and behavioral weight loss and weight control interventions for adults with type 2 diabetes. SEARCH STRATEGY: Studies were obtained from computerized searches of multiple electronic bibliographic databases, supplemented with hand searches of selected journals and consultation with experts in obesity research. The last search was conducted May, 2004. SELECTION CRITERIA: Studies were included if they were published or unpublished randomized controlled trials in any language, and examined weight loss or weight control strategies using one or more dietary, physical activity, or behavioral interventions, with a follow-up interval of at least 12 months. DATA COLLECTION AND ANALYSIS: Effects were combined using a random effects model. MAIN RESULTS: The 22 studies of weight loss interventions identified had a 4,659 participants and follow-up of 1 to 5 years. The pooled weight loss for any intervention in comparison to usual care among 585 subjects was 1.7 kg (95 % confidence interval [CI] 0.3 to 3.2), or 3.1% of baseline body weight among 517 subjects. Other main comparisons demonstrated nonsignificant results: among 126 persons receiving a physical activity and behavioral intervention, those who also received a very low calorie diet lost 3.0 kg (95% CI -0.5 to 6.4), or 1.6% of baseline body weight, more than persons receiving a low-calorie diet. Among 53 persons receiving identical dietary and behavioral interventions, those receiving more intense physical activity interventions lost 3.9 kg (95% CI -1.9 to 9.7), or 3.6% of baseline body weight, more than those receiving a less intense or no physical activity intervention. Comparison groups often achieved significant weight loss (up to 10.0 kg), minimizing between-group differences. Changes in glycated hemoglobin generally corresponded to changes in weight and were not significant when between-group differences were examined. No data were identified on quality of life and mortality. AUTHORS' CONCLUSIONS: Weight loss strategies using dietary, physical activity, or behavioral interventions produced small between-group improvements in weight. These results were minimized by weight loss in the comparison group, however, and examination of individual study arms revealed that multicomponent interventions including very low calorie diets or low calorie diets may hold promise for achieving weight loss in adults with type 2 diabetes.

Adult↗

PubMed2005

Long-term non-pharmacological weight loss interventions for adults with prediabetes.

BACKGROUND: Most persons with prediabetes (impaired glucose tolerance or impaired fasting glucose) are overweight, and obesity worsens the metabolic and physiologic abnormalities associated with this condition. Prediabetes is an important risk factor for the development of type 2 diabetes. OBJECTIVES: The objective of this review was to assess the effectiveness of dietary, physical activity, and behavioral weight loss, and weight control interventions for adults with prediabetes. SEARCH STRATEGY: Studies were obtained from computerized searches of multiple electronic bibliographic databases, supplemented by hand searches of selected journals, and consultation with experts in obesity research. The last search was conducted May, 2004. SELECTION CRITERIA: Studies were included if they were published or unpublished randomized controlled trials in any language and examined weight loss or weight control strategies using one or more dietary, physical activity, or behavioral interventions, with a follow-up interval of at least 12 months. DATA COLLECTION AND ANALYSIS: Effects were combined using a random-effects model. MAIN RESULTS: Nine studies were identified, with a total of 5,168 participants. Follow-up ranged from 1 to 10 years. Quantitative synthesis was limited by the heterogeneity of populations, settings, and interventions and by the small number of studies that examined outcomes other than weight. Overall, in comparisons with usual care, four studies with a follow-up of one year reduced weight by 2.8 kg (95 % confidence interval (CI) 1.0 to 4.7) (3.3% of baseline body weight) and decreased body mass index by 1.3 kg/m(2) (95% CI 0.8 to 1.9). Weight loss at two years was 2.6 kg (95% CI 1.9 to 3.3) (three studies). Modest improvements were noted in the few studies that examined glycemic control, blood pressure, or lipid concentrations (P > 0.05). No data on quality of life or mortality were found. The incidence of diabetes was significantly lower in the intervention groups versus the controls in three of five studies examining this outcome at 3 to 6 years follow-up. AUTHORS' CONCLUSIONS: Overall, weight loss strategies using dietary, physical activity, or behavioral interventions produced significant improvements in weight among persons with prediabetes and a significant decrease in diabetes incidence. Further work is needed on the long-term effects of these interventions on morbidity and mortality and on how to implement these interventions in diverse community settings.

Adult↗

PubMed2005

Risks posed by trace organic contaminants in coastal sediments in the Pearl River Delta, China.

Local marine environments in China's Pearl River Delta (PRD), the most rapidly developing region in one of the world's fastest growing economies, have been experiencing significant environmental stress during the past decades. This investigation was conducted to determine the status and trends of persistence organic pollutants (POPs) such as polycyclic aromatic hydrocarbons (PAHs), petroleum hydrocarbons (PHCs), polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides and dioxin-related compounds in marine sediments collected from sixteen coastal stations in the Pearl River Delta (PRD) in March 2003. Elevated concentrations of PAHs (94-4300 ng/g), PCBs (6.0-290 ng/g), PHCs (14-150 microg/g), and DDTs (1.4-600 ng/g) were detected in sediment samples. In addition, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like activities in the sediment samples were estimated to range from 0.3 to 440 pg TCDD-EQ/g. Sediments collected from Xiashan contained the greatest concentrations of trace organic contaminations amongst all the sampling stations in the present study. The degree of trace organic contamination was, in general, more severe at stations situated along the west shores of the PRD than their counterparts in the east. A preliminary assessment was performed to examine the probable risks to the marine ecosystem due to POPs. The results showed that OC pesticide contamination in the PRD was particularly serious and might pose a threat to the health of the marine inhabitants.

China↗

PubMed2005

Development of mild extraction methods for the analysis of natural dyes in textiles of historical interest using LC-diode array detector-MS.

Analysis of dyes extracted from textiles of historical interest can give valuable information as to where, when, and how the textiles were made. The most widely used method for extraction of colorants involves heating with HCl, which frequently decomposes glycosidic dye components to their parent aglycons, with consequent loss of information about the source of the dye. This is particularly true for flavonoid dyes, many of which are glycosides. We have developed or improved upon two mild textile extraction methods that use ethylenediaminetetraacetic acid (EDTA) and formic acid and are efficient in extracting dyes, but preserve glycosidic linkages. The relative efficiencies of the HCl, EDTA, and formic acid extraction methods are compared by analyzing extracts of dyed samples of silk using HPLC coupled with diode array and mass spectrometric detection. HPLC profiles of EDTA or formic acid extracts of silk dyed, for example, with pagoda tree buds and onionskins are clearly distinguishable as to the plant material used, whereas profiles of HCl extracts are not. Thus, extraction of textiles with EDTA or formic acid reagents can yield significantly more information about the original dyestuff than can extraction with a strong acid.

Journal Article↗