Search

Based on the capability of silyl ethers for efficient glycosylation, the new MTEAN glycosylation protocol utilizing 8-methyltosylaminoethynyl-1-naphthyl (MTEAN) glycosides as donors were extended to one-pot synthesis of nucleosides, late-stage modification of bioactive molecules, and stereoselective construction of 1,2-cis-glucosidic linkages using silyl ethers of the acceptors. Moreover, the reaction mechanism was systematically investigated by control reactions and side product characterizations, leading to the determination of a TfOH-catalyzed ynamide functionality-initiated process, which was further corroborated by identifications of the departure form of leaving group and the real catalyst.

Background: The coexistence of thoracic fractures and blunt aortic injury (BAI) is potentially catastrophic and easy to be missed in acute trauma settings. Data regarding patients with thoracic fractures complicated with BAI are limited. Methods: The authors conducted a prospective, observational, single-center study including patients with thoracic burst fractures. A multivariate logistic regression model was developed to determine the risk factors of aortic injury. Results: In total, 124 patients with burst fractures of the thoracic spine were included. The incidence of BAI was 11.3% (14/124) in patients with thoracic burst fractures. Among these patients, 11 patients with BAI were missed diagnoses. The main risk factors of BAI were as follows: Injury severity score (OR 1.184, 95% CI, 1.072–1.308, p = 0.001), mechanism of injury, such as crush (OR 10.474, 95% CI, 1.905–57.579, p = 0.007), flail chest (OR = 4.917, 95% CI, 1.122–21.545, p = 0.035), and neurological deficit (OR = 8.299, 95% CI, 0.999–68.933, p = 0.05). Conclusions: BAI (incidence 11.3%) is common in patients with burst fractures of the thoracic spine and is an easily missed diagnosis. We must maintain a high suspicion of injury for BAI when patients with thoracic burst fractures present with these high-risk factors.

A question that routinely arises in medical device clinical studies is the homogeneity across demographic subgroups, geographical regions, or investigational sites of the enrolled patients in terms of treatment effects or outcome variables. The main objective of this paper is to discuss statistical concepts and methods for the assessment of such homogeneity and to provide the practitioner a statistical framework and points to consider in conducting homogeneity assessment. Demographic subgroups, geographical regions, and investigational sites are discussed separately as each has its unique issues. Specific considerations are also given to randomized controlled trials, non-randomized comparative studies, and single-arm studies. We point out that judicious use of statistical methods, in conjunction with sound clinical judgment, is essential in handling the issue of homogeneity of treatment effect in medical device clinical studies.

Bladder cancer has easy recurrence characteristics, but its occurrence and development mechanism are still unclear. Non-coding RNA is a kind of RNA that exists widely and cannot be translated into proteins, which has played a key role in the regulation of biological functions of tumor cells. However, the regulation mechanism of non-coding RNA on bladder tumors is not fully understood. By microarray analysis and database analysis, we found that LINC00511 was significantly highly expressed in bladder cancer. The expressions of LINC00511, miR-143-3p, and PCMT in bladder cancer tissues and cells were detected by quantitative reverse transcription–polymerase chain reaction. The relationship between the expressions of miR-143-3p and PCMT1 and the clinicopathological parameters of the tumor was analyzed. The proliferation and invasion of bladder cancer cells were detected by MTT assay and Transwell assay. The expression levels of E-cadherin and vimentin in bladder cancer cells were detected by Western blot. Cell apoptosis was detected by flow cytometry. In vivo, TCCSUP or SW780 cells were inoculated into BALB/c nude mice to detect tumor volume and weight. Bioinformatics and dual luciferase reporter gene were used to analyze the relationship between LINC00511 and miR-143-3p and its downstream target gene PCMT1. The results showed that LINC00511 could target miR-143-3p/PCMT1 to regulate the proliferation, migration, and apoptosis of bladder cancer TCCSUP or SW780 cells and promote the occurrence and development of bladder cancer.

A new type of polymer emulsion was prepared by the copolymerization of DAAM and VAc monomer with high solid content and storage stability. By addition of ADH (ketonic hydrazide cross-linking reaction), the polymer emulsion can be cross-linked at room temperature. It was found that the degree of cross-linking of the polymer reaches 71.85%, and the resistance to boiling water reaches 180min at the maximum of DAAM of 2% and DAAM / ADH = 1/1.

Thyroid hormone receptor interactor 13 (TRIP13) has been reported to be overexpressed in serval types of human cancers, and regulate tumor cell proliferation, migration and invasion. However, the role of TRIP13 in prostate cancer was still unclear. In our study, the correlation between TRIP13 expression and clinical parameters including prognosis was evaluated in 160 prostate cancer patients. Moreover, the MTT assay, cell migration and invasion assays were performed to assess the effect of TRIP13 on prostate cancer cell biological behaviour. In our results, the expression status of TRIP13 was observed to be elevated in prostate cancer tissue samples through analyzing microarray (GSE55945). Furthermore, mRNA and protein TRIP13 expression were confirmed to be overexpressed in prostate cancer tissue samples and cell lines. High-expression of TRIP13 was correlated with present lymph node involvement, distant metastasis, high Gleason score, levels of serum PSA and poor prognosis in prostate cancer patients. The gain-of-function and loss-of-function studies suggested that TRIP13 functioned as oncogene to regulate prostate cancer cell proliferation, migration, invasion through controlling YWHAZ and epithelial-mesenchymal transition (EMT)-associated genes. In conclusion, TRIP13 is correlated with clinical progression and poor prognosis, and serves as oncogene in prostate cancer.

Chest trauma was the third most common cause of death in polytrauma patients, accounting for 25% of all deaths from traumatic injury. Chest trauma involves in injury to the bony thorax, intrathoracic organs and thoracic medulla. This study aimed to investigate the incidence, clinical characteristics, and outcome of polytrauma patients with pulmonary contusion, flail chest and upper thoracic spinal injury.Patients who met inclusion criteria were divided into groups: Pulmonary contusion group (PC); Pulmonary contusion and flail chest group (PC + FC); Pulmonary contusion and upper thoracic spinal cord injury group (PC + UTSCI); Thoracic trauma triad group (TTT): included patients with flail chest, pulmonary contusion and the upper thoracic spinal cord injury coexisted. Outcomes were determined, including 30-day mortality and 6-month mortality.A total 84 patients (2.0%) with TTT out of 4176 polytrauma patients presented to Tongji trauma center. There was no difference in mean ISS among PC + FC group, PC + UTSCI group and TTT group. Patients with TTT had a longer ICU stay (21.4 days vs. 7.5 and 6.2; p0.01), relatively higher 30-day mortality (40.5% vs. 6.0% and 4.3%; p0.01), and especially higher 6-month mortality (71.4% vs. 6.5%, 13.0%; p0.01), compared to patients with PC + FC or with PC + UTSCI. The leading causes of death for patients with TTT were ARDS (44.1%) and pulmonary infection (26.5%) during first 30 days after admission. For those patients who died later than 30 days during the 6 months, the predominant underlying cause of death was MOF (53.8%).Lethal triad of thoracic trauma (LTTT) were described in this study, which consisting of pulmonary contusion,flail chest and the upper thoracic spine cord injury. Like the classic "lethal triad", there was a synergy between the factors when they coexist, resulting in especially high mortality rates. Polytrauma patients with LTTT were presented relatively high 30-day mortality and 6 months mortality. We should pay much more attention to the patients with LTTT for further minimizing complications and mortality.

Transcatheter aortic valve replacement (TAVR) is a less invasive alternative approach to surgery. Individual randomized clinical trials evaluating the safety and efficacy of TAVR were mostly underpowered for conducting separate analyses for women and men. We pooled data from premarket TAVR clinical trials comparing short (30 days)- and long-term (∼2 years) outcomes by sex.Patient-level data from the TAVR arms of six clinical trials were pooled (2515 patients). Random-effects models for time-to-event outcomes (odds ratios [ORs] for 30-day outcomes and hazard ratios [HRs] for complete follow-up for mortality, ischemic stroke, kidney injury, major bleeding, myocardial infarction, and device migration) and dichotomous outcomes (ORs for reintervention, rehospitalization, and pacemaker implantation) were then fit to directly compare outcomes between women and men.Overall, the pattern of individual comorbidities was more severe in men. There was no difference in mortality risk at 30 days (female-to-male OR = 1.00 [0.69-1.46]); however, at follow-up completion (∼2 years post-TAVR), women had a 24% lower mortality risk than men (HR = 0.76 [95% CI: 0.65-0.89]). Women also had a 30% lower risk of kidney injury at 30 days (OR = 0.70 [0.49-0.98]), which increased to 33% over the complete follow-up period (HR = 0.67 [0.51-0.87]). Major bleeding was more common in women compared to men at both 30 days (OR = 1.44 [1.19-1.76]) and long-term follow-up (HR = 1.22 [1.04-1.43]). For dichotomous outcomes, women had a 68% lower risk for reinterventions (OR = 0.32 [0.18-0.58]). We did not observe any difference in the risk of ischemic stroke, myocardial infarction, device migration, rehospitalizations, or pacemaker implantations between sexes.This patient-level data meta-analysis of six premarket clinical trials found that women who received TAVR had fewer comorbidities at baseline. Acute outcomes (30 day) with respect to mortality were similar. Women were observed to have a lower risk of kidney injury, but higher risk of major bleeding compared to men receiving TAVR at 30 days. At complete follow-up, statistically significant advantages for women emerged in improved survival and lower reintervention risk. No differences in ischemic stroke, pacemaker implantation, or rehospitalization were observed. That women are healthier at baseline and develop fewer postprocedural complications than men may explain their higher survival.

Secondary Vocational education is responsible for cultivating the talents for the economy, as well as to promote scientific and technological research and innovation of the two key responsibilities. Although secondary vocational schools is based on cultivating the practical ability of students, math and other basic disciplines of teaching status is not optimistic. Math experiments based on information technology can stimulate the enthusiasm of students to learn math, improve the overall quality of vocational students, and provide a solid foundation for vocational students to take the professional operation and secondary vocational education. It in-depth implements the concept of combining course with engineering and engineering of "Learning content is work, through the work to achieve learning" in theoretical practice integration curriculum. In this study, we investigated the status quo of math experiments and students' attitude to math experiments and put forward the corresponding suggestions and strategies.

Nanometer titanium dioxide has not only small size effect, quantum dimension effect, surface and interface effects and macroscopic quantum tunnel effect, but also photocatalytic effect. Vac-acrylate emulsion is one of the important emulsion adhesive. It has good properties for coating, high cohesive strength, no pollution. It has the special functions with few nano-TiO2.In this paper, method of modification about nanometer TiO2was introduced via cellulose sodium. The modified nanometer titanium dioxide was added to the material of the preparation of acrylic emulsion including vinyl acetate, butyl acrylate, acrylic acid and methyl methacrylate to synthesize composite of nano-TiO2/vac-acrylic emulsion. According to the performance analysis of solid content of emulsion and stabilization, we can find that when the use level of dosage, emulsifier, nano-TiO2is 0.5%, 3.2%, 0.7%, and emulsion has the best combination property.

This paper mainly investigate how to use cheaply-priced, safety and sanitate of natural clay or nanosilica as coagulant and adsorbent combined with polyaluminium chloride to treat low temperature and low turbidity water .Wastewater in paper mill was used as the water samples, by measuring the absorbance and the turbidity of the water samples to determine the flocculation effect. The results showed that flocculation effect of water samples with different natural clay and nanoSiO2combined with PAC had the same change tendency. The order of coagulation effects was bentonite > diatomite > kaolin > attapulgite. nano-SiO2as coagulant associated with PAC could attain best coagulation effect with least amount from the analysis of absorbance or turbidity.

Sequential extraction was used to characteristic the heavy metals (Cd, Cr, Zn, Cu, Ni and Pb) and trace element (As) studied in these urban dusts. The ratio of the average total content (F1+F2+F3+F4+R) to the corresponding background value of Beijing soil decreased in the order of Cd>Pb>Cu>Zn>Ni>Cr>As. For fraction distribution, residual form predominated among for Zn, Ni, Cr and Pb. Oxidizable fraction was the leading fraction for Cd and Cu and was the second dominated fraction for Zn and Ni. The results of Risk assessment code (RAC) showed the medium environmental risk of Cd was found in Dongcheng and East 4thRing districts, while a high environmental risk for Cr was present in Xizhimen and Yongdingmen areas.

A phthalazinone monomer with an allyl group, i.e. 4-(3-allyl-4-hydroxyphenyl)phthalazin-1(2H)-one, was synthesized and then copolymerized with 4-(4-hydroxylphenyl)(2H)-phthalazin-1-one and 2,6-diflurobenzonitrile by means of aromatic nucleophilic polycondensation to provide a series of crosslinkable poly(aryl ether nitrile)s. The virgin copolymers exhibited good solubility in polar organic solvents with relative high molecular weights (Mw: 45,130–58,403, inherent viscosities: 0.58–0.75 dL/g). After cross-linking, the thermal stability and solvent resistance of the polymer increased.

Ethnopharmacological relevance Depression induce distressed emotional state and cognitive deficits simultaneously, which both should be improved in the treatment. Hemerocallis citrina Baroni (HC) is a traditional herbal medicine in Eastern-Asia areas and the total phenols extract of HC (HCPE) contains the main active ingredients. It has been reported that HC has the emotional improvement effect. But the cognitive effect of HC was seldom researched. Aim of the study We designed to evaluate the antidepressant and cognitive improvement effect of HCPE using a chronic unpredictable mild stress (CUMS) model, and the potential mechanisms were explored by investigating the corticosterone (CORT), monoamine neurotansmitters, brain-derived neurotropic factor (BDNF) and oxidative stress. Materials and methods The depression rats were induced by CUMS procedures and treated with HCPE (10, 20, 40 mg/kg/day, by gastric gavage). The antidepressant effect was evaluated by sucrose preference test, open field test and body weight, while the cognitive improvement was investigated using morris water maze test. Besides, the levels of monoamine neurotransmitters in the hippocampus and frontal cortex were measured by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The serum CORT and BDNF in hippocampus were test using enzyme-linked immunosorbent assay (ELISA) kits. The oxidative stress indicators in frontal cortex were also analyzed. Results HCPE (40 mg/kg) improved the emotion and cognition related behaviors in depression effectively. Moreover, HCPE increased the neurotransmitters concentration (5-HT, DA and NE) in the hippocampus and frontal cortex compared with CUMS rats. Meanwhile, the CUMS induced changes of serum corticosterone level and the hippocampus BDNF level were reversed. Besides, HCPE reduced malondialdehyde (MDA) in the frontal cortex of model rats. Conclusion It suggested that HCPE could improve the depression-like emotional status and associated cognitive deficits in CUMS rats, which might be mediated by regulation of neurotransmitters and BDNF levels in brain, alleviation of corticosterone level as well as the alleviation of oxidative stress.

Phosphorus (P) is the limiting macronutrient for primary production in most lakes. Sediment characteristics are strongly correlated to the internal P loading in lakes. This study investigated speciation of P, Fe, Al, and Ca in sediments of six sampling sites with varying trophic status in Baiyangdian Lake of North China during the period of July 2008 and March 2009. The results of sequential extraction experiments of the top sediments showed that total extractable P ranged approximately from 13 to 28 μmol g−1 for all sampling sites and the rank order of P-fractions was HCl–P > NaOH85–P > NaOH25–P > BD–P > NH4Cl–P. BD–P and BD–Fe had a consistent change with seasons. Their concentrations were both much higher in early spring and mid-autumn. BD–Fe, Al extracted with NaOH at 25°C and 85°C affected corresponding P concentration in sediments, while high concentration of extractable Ca from sediments showed no direct effects. According to the Kopacek et al. model of the molar ratios of Al:Fe and [NaOH25–Al]:[NH4Cl–P + BD–P], there was potential P release from sediments twice a year for some hypereutrophic sites in early spring and mid-autumn, especially in the former season.

PURPOSE: To investigate myopia progression in Correction of Myopia Evaluation Trial (COMET) participants who switched to soft contact lenses (CLs) vs. remained in spectacles after the clinical trial ended. METHODS: Four hundred sixty-nine ethnically diverse, 6- to 11-year-old myopic children were randomly assigned to wear single vision lenses (SVLs) or progressive addition spectacle lenses (PALs) for 5 years as part of COMET. Afterwards they could choose another lens type, including CLs. Data in this article are from 286 participants who wore their original spectacle lenses for 6 years (n = 199) or wore CLs most or all the time between the 5- and 6-year visits (n = 87). Refractive error and axial length (AL) were measured after cycloplegia with 1% Tropicamide. The primary outcome was myopia progression between the 5- and 6-year visits. Two-year myopia progression was evaluated in a subset of 183 participants who wore the same lens type for an additional year. Myopia progression and AL were compared between the two lens groups using multiple linear regression. RESULTS: Participants in the two groups were similar with respect to age, ethnicity, myopia at 5-years, accommodation and phoria, but more girls switched to CLs than remained in spectacles (p < 0.0001). Mean (+/-SD) myopia progression was higher (p = 0.003) after 1 year in the CL group[-0.28+/- 0.33 diopter (D)] than the spectacle group (-0.14+/- 0.36 D), and remained higher after 2 years in the 2-year subset (-0.52+/- 0.46 D vs.-0.25+/- 0.39 D, p < 0.0001). Results were similar after adjustment for related factors. No significant differences in AL were found between groups after adjustment. Corneal curvature remained unchanged in both groups. CONCLUSIONS: COMET children switching from glasses to CLs experienced a small, statistically significant but clinically inconsequential increase in myopia progression.

Poly(phthalazinone ether nitrile) (PPEN) block copolymers containing polysiloxane were prepared so as to create a strongly hydrophobic polymer surface. The copolymers were synthesized from eugenol end-capped polydimethylsiloxane (PDMS) and fluoro-terminated PPEN oligomers by the aromatic nucleophilic substitution polycondensation in the presence of dimethyl sulfoxide/o-dichlorobenzene and K 2 CO 3 as solvents and catalyst, respectively. The resultant copolymers were characterized by FTIR, 1 H NMR, and gel permeation chromatography. XPS analysis results indicated that the copolymer film had a very rich PDMS segment surface. Atomic force microscopy further showed that there existed a continuous PDMS phase on the copolymer surface and PPEN as the dispersive particles was dispersed at diameters between 0.1 and 0.3 nm. The enrichment of PDMS in the copolymer surface could be responsible for an increase of surface water repellency (113.4°).

Objective: To investigate the protein expression of matrix metalloproteinase 2 (MMP2) and its clinical significance in laryngeal cancer. Methods: A comprehensive search for the related literature published in China and other countries was conducted in a variety of databases, including MEDLINE, Embase, China Academic Journals Full-text Database, Wanfang Data and VIP Database. A total of seven case-control studies were included in the final systematic assessment. A meta-analysis software program was used to statistically analyze the raw data from each study for the calculation of the pooled odds ratio (OR) and 95% confidence interval (95% CI). Results: The meta-analysis indicated that, compared with normal laryngeal tissue, the MMP2 protein was highly expressed in the laryngeal cancer tissue [OR=21.67; 95% CI: 11.61-40.43; P

To examine the relationship of choroidal thickness with axial length (AL) and myopia in young adult eyes in the ethnically diverse Correction of Myopia Evaluation Trial (COMET) cohort.Cross-sectional, multicenter study.In addition to measures of myopia by cycloplegic autorefraction and AL by A-scan ultrasonography, participants underwent optical coherence tomography imaging of the choroid in both eyes at their last visit (14 years after baseline). Using digital calipers, 2 independent readers measured choroidal thickness in the right eye (left eye if poor quality; n = 37) at 7 locations: fovea and 750, 1500, and 2250 μm nasal (N) and temporal (T) to the fovea.Choroidal thickness measurements were available from 294 of 346 (85%) imaged participants (mean age: 24.3 ± 1.4 years; 44.9% male) with mean myopia of -5.3 ± 2.0 diopters and mean AL of 25.5 ± 1.0 mm. Overall, choroidal thickness varied by location (P.0001) and was thickest at the fovea (273.8 ± 70.9 μm) and thinnest nasally (N2250, 191.5 ± 69.3 μm). Multivariable analyses showed significantly thinner choroids in eyes with more myopia and longer AL at all locations except T2250 (P ≤ .001) and presence of peripapillary crescent at all locations except T1500 and T2250 (P ≤ .0001). Choroidal thickness varied by ethnicity at N2250 (P.0001), with Asians having the thinnest and African Americans the thickest choroids.Choroids are thinner in longer, more myopic young adult eyes. The thinning was most prominent nasally and in eyes with a crescent. In the furthest nasal location, ethnicity was associated with choroidal thickness. The findings suggest that choroidal thickness should be evaluated, especially in the nasal regions where myopic degenerations are most commonly seen clinically.

We examined whether the X-ray repair cross-complementing group 1 (XRCC1) Arg399Gln polymorphism is a risk factor for bladder cancer by conducting a meta-analysis. We searched the Pubmed and Embase databases for study retrieval. This meta-analysis examined 16 case-control studies, including 892 prostate cancer cases and 1020 healthy controls. Meta-analysis results based on these studies showed no significant association between the XRCC1 Arg399Gln polymorphism and bladder cancer risk in comparisons of the glutamine (Gln) allele vs arginine (Arg) allele, Arg/Arg vs (Gln/Gln + Gln/Arg), Gln/Gln vs (Gln/Arg + Arg/Arg), Gln/Gln vs Arg/Arg, and Gln/Arg vs Arg/Arg [odds ratio (OR) = 0.96, 95% confidence interval (CI) = 0.80-1.16, P = 0.70; OR = 1.13, 95%CI = 0.70-1.82, P = 0.62; OR = 0.92, 95%CI = 0.79-1.07, P = 0.29; OR = 0.90, 95%CI = 0.69-1.16, P = 0.42; OR = 0.89, 95%CI = 0.75-1.05, P = 0.17, respectively]. In subgroup analysis by ethnicity, no association was observed between the XRCC1 Arg399Gln polymorphism and bladder cancer risk in Caucasian, Mongoloid, or black populations. We identified no association between the XRCC1 Arg399Gln polymorphism and bladder cancer risk.

Apolipoprotein (apo) E4 is a major risk factor for Alzheimer's disease, and many studies have suggested that apoE has isoform-specific effects on the deposition or clearance of amyloid beta (Abeta) peptides. We examined the effects of apoE isoforms on the processing of amyloid precursor protein (APP) and on Abeta production in rat neuroblastoma B103 cells stably transfected with human wild-type APP695 (B103-APP). Lipid-poor apoE4 increased Abeta production in B103-APP cells to a greater extent than lipid-poor apoE3 (60% vs. 30%) due to more pronounced stimulation of APP recycling by apoE4 than apoE3. The difference in Abeta production was abolished by preincubating the cells with the receptor-associated protein (25 nM), which blocks the low-density lipoprotein receptor-related protein (LRP) pathway, or by reducing LRP expression by small interference RNA. The differences were also attenuated by replacing Arg-61 with threonine in apoE4 or pretreating apoE4 with small molecules, both of which abolish apoE4 intramolecular domain interaction. Thus, apoE4 appears to modulate APP processing and Abeta production through both the LRP pathway and domain interaction. These findings provide insights into why apoE4 is associated with increased risk for Alzheimer's disease and may represent a potential target for drug development.

A new flow injection on-line sequential extraction procedure coupled with hydride generation atomic fluorescence spectrometry (HG-AFS) was developed for rapid and automatic fractionation of arsenic in soils. The developed methodology involved a three-step sequential extraction procedure with deionized water, KOH solution, and HCl solution. 25mg of the soil sample packed into a microcolumn (4mm i.d. x 3cm long) was dynamically extracted by continuously pumping each individual extractant through the column. The extracted arsenic solution was merged with 4% (m/v) K(2)S(2)O(8) solution for on-line oxidation of all arsenic species into As(V). The total extracted arsenic was on-line detected by HG-AFS, and quantitated using an on-line standard addition calibration strategy. The total time for the three-step sequential extraction and on-line detection lasted only 10min. The developed methodology offers several advantages over conventional batch sequential extraction protocols, including minimization of readsorption/redistribution problem, improvement of accuracy, high speed, less amounts of sample/reagents required, less risk of contamination and analyte loss. The developed methodology was successfully applied to the fractionation of arsenic in certified soil reference materials.

Background Visual loss from optic neuropathy rarely occurs in the perioperative period in patients who have undergone nonocular surgery. We performed a retrospective, matched, case–control study to determine the incidence of perioperative optic neuropathy (PON) after cardiac surgery with the use of cardiopulmonary bypass (CPB) and to determine risk factors that may lead to this potentially devastating complication. Methods Medical records of all patients undergoing cardiac surgery during a 9-year period were reviewed retrospectively to identify visual loss from acute unilateral and bilateral optic neuropathy during the perioperative period that had developed in patients. Data were collected from these patients and compared with data from control subjects matched for age, gender, risk factors for vascular disease, and type of surgery to determine the incidence of and potential risk factors for PON. Results Of 9701 surgical patients requiring CPB, 11 patients (0.113%) with PON were identified. Although both the absolute and relative drop in hemoglobin during the perioperative period approached statistical significance, no other putative risk factors were identified. Conclusions The risk of PON associated with cardiac surgery in which CPB is used is low but substantial. The factors that lead to the condition remain unknown, although the presence of systemic vascular disease and both the absolute and relative drop in hemoglobin during the perioperative period seem to be important. Because PON often causes profound permanent visual loss, we recommend that patients, particularly those with systemic vascular disease, for whom cardiac surgery with CPB is planned, be made aware of this potential complication.

A simple and cost-effective method for speciation analysis of trace mercury in seafood was developed by on-line coupling flow injection microcolumn displacement sorption preconcentration to high-performance liquid chromatography (HPLC) with UV detection. The methodology involved the presorption of the Cu-PDC (pyrrolidine dithiocarbamate) chelate onto a microcolumn packed with a cigarette filter sorbent, simultaneous preconcentration of Hg(II), methylmercury (MeHg), ethylmercury (EtHg), and phenylmercury (PhHg) onto the microcolumn through a displacement reaction with the presorbed Cu-PDC, and their subsequent elution from the microcolumn for on-line HPLC separation. Interferences from heavy metal ions with lower stability of their PDC chelates relative to Cu-PDC were minimized without the need of any masking agents. With the consumption of 4.0 ml of sample solution, the enrichment factors were about 80. The detection limits were 10-25 ng g(-1) (as Hg) in fresh tissue. Precision (R.S.D. (%), n = 5) ranged from 2 to 3% at the 500 microg l(-1) (as Hg) level. The developed technique was validated by analyzing a certified reference material (DORM-2, dogfish-muscle), and was shown to be useful for mercury speciation in real seafood samples.

To describe visual acuity (VA) testing and scoring methods used in multicenter randomized clinical trials in ophthalmology in the United States (USA) sponsored by the National Eye Institute (NEI).A survey was conducted among multicenter studies in the US that included one or more randomized clinical trials and were sponsored by the NEI, National Institutes of Health. To be included in the survey, a study had to have VA reported in one or more publications or patient eligibility based on VA, a majority of study subjects 13 years of age or older, and a patient population primarily or exclusively from the US. A standard survey form was completed for each study based on information presented in the study manual of procedures and publications. Findings were summarized and displayed with frequency distributions.The survey included 24 studies, each with enrollment initiated in the period 1972 to 1999. VA was one of the study eligibility criteria for 19 (79%) studies, and VA or change in VA was the primary outcome in 12 (50%) studies. ETDRS charts have been employed in 16 of 19 studies initiated after the charts were published in 1982. All studies but one specified in the documents reviewed that VA testing was performed at multiple VA test distances. For studies that used ETDRS charts, methods of converting VA scores obtained at different test distances to a common scale fell into two categories: 11 studies used a method similar in nature to that first reported in the Macular Photocoagulation Study, and 7 studies used a method similar in nature to that first reported in the Krypton-Argon Regression of Neovascularization Study. conclusion The development of the ETDRS charts and a custom light box has led to more uniformity in VA test charts and chart illumination. However, details of VA measurement protocols vary widely from study to study. To assure comparable data across studies and ocular conditions, it would be useful to have a standard VA testing and scoring protocol with provisions for testing different levels of visual acuity that recommends a single method for converting scores from different test distances to a common scale and standard conversion of "off the chart" VA levels for calculation of means and changes in VA.

Human apolipoprotein E4 (apoE4) binds preferentially to lower density lipoproteins, including very low density lipoproteins, and is associated with increased risk of atherosclerosis and neurodegenerative disorders, including Alzheimer's disease. This binding preference is the result of the presence of Arg-112, which causes Arg-61 in the amino-terminal domain to interact with Glu-255 in the carboxyl-terminal domain. ApoE2 and apoE3, which have Cys-112, bind preferentially to high density lipoproteins (HDL) and do not display apoE4 domain interaction. Mouse apoE, like apoE4, contains the equivalent of Arg-112 and Glu-255, but lacks the critical Arg-61 equivalent (it contains Thr-61). Thus, mouse apoE does not display apoE4 domain interaction and, as a result, behaves like human apoE3, including preferential binding to HDL. To assess the potential role of apoE4 domain interaction in atherosclerosis and neurodegeneration, we sought to introduce apoE4 domain interaction into mouse apoE. Replacing Thr-61 in mouse apoE with arginine converted the binding preference from HDL to very low density lipoproteinsin vitro, suggesting that apoE4 domain interaction could be introduced into mouse apoEin vivo. Using gene targeting in embryonic stem cells, we created mice expressing Arg-61 apoE. Heterozygous Arg-61/wild-type apoE mice displayed two phenotypes found in human apoE4/E3 heterozygotes: preferential binding to lower density lipoproteins and reduced abundance of Arg-61 apoE in the plasma, reflecting its more rapid catabolism. These findings demonstrate the successful introduction of apoE4 domain interaction into mouse apoEin vivo. The Arg-61 apoE mouse model will allow the effects of apoE4 domain interaction in lipoprotein metabolism, atherosclerosis, and neurodegeneration to be determined.

To use the Gompertz function to estimate the age and the amount of myopia at stabilization and to evaluate associated factors in the Correction of Myopia Evaluation Trial (COMET) cohort, a large ethnically diverse group of myopic children.The COMET enrolled 469 ethnically diverse children aged 6 to younger than 12 years with spherical equivalent refraction between -1.25 and -4.50 diopters (D). Noncycloplegic refraction was measured semiannually for 4 years and annually thereafter. Right eye data were fit to individual Gompertz functions in participants with at least 6 years of follow-up and at least seven refraction measurements over 11 years. Function parameters were estimated using a nonlinear least squares procedure. Associated factors were evaluated using linear regression.In total, 426 participants (91%) had valid Gompertz curve fits. The mean (SD) age at myopia stabilization was 15.61 (4.17) years, and the mean (SD) amount of myopia at stabilization was -4.87 (2.01) D. Ethnicity (P0.0001) but not sex or the number of myopic parents was associated with the age at stabilization. Ethnicity (P = 0.02) and the number of myopic parents (P = 0.01) but not sex were associated with myopia magnitude at stabilization. At stabilization, African Americans were youngest (mean age, 13.82 years) and had the least myopia (mean, -4.36 D). Participants with two versus no myopic parents had approximately 1.00 D more myopia at stabilization. The age and the amount of myopia at stabilization were correlated (r = -0.60, P0.0001).The Gompertz function provides estimates of the age and the amount of myopia at stabilization in an ethnically diverse cohort. These findings should provide guidance on the time course of myopia and on decisions regarding the type and timing of interventions.