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High blood pressure variability (BPV) is a risk factor for cognitive decline and dementia, but its association with cortical thickness is not well understood. Here we use a topographical approach, to assess links between long-term BPV and cortical thickness in 478 (54% men at baseline) community dwelling older adults (70-88 years) from the ASPirin in Reducing Events in the Elderly NEURO sub-study. BPV was measured as average real variability, based on annual visits across three years. Higher diastolic BPV was significantly associated with reduced cortical thickness in multiple areas, including temporal (banks of the superior temporal sulcus), parietal (supramarginal gyrus, post-central gyrus), and posterior frontal areas (pre-central gyrus, caudal middle frontal gyrus), while controlling for mean BP. Higher diastolic BPV was associated with faster progression of cortical thinning across the three years. Diastolic BPV is an important predictor of cortical thickness, and trajectory of cortical thickness, independent of mean blood pressure. This finding suggests an important biological link in the relationship between BPV and cognitive decline in older age., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Zinc oxide nanoparticles (ZnONPs) and melatonin (MT) have been known to regulate heavy metal toxicities in plants in some studies, the effect of their combined use on cadmium (Cd) uptake by wheat (Triticum aestivum L.) and underlying mechanisms is largely unknown. Thus, plant growth, uptake and translocation of Cd mediated by soil applied ZnONPs and foliar applied MT were investigated in wheat grown in Cd polluted soil under ambient conditions. The results depicted that ZnONPs stimulated the growth, chlorophyll contents, and yield of wheat in a dose additive way and this effect was further increased with foliar application of MT. 100 mg/kg of ZnONPs alone enhanced the grain yield by 60.5 % and this increase was about 177.5 % under combined ZnONPs and 100 μM MT treatment. ZnONPs treatments decreased Cd concentration whereas increased zinc (Zn) concentrations in shoots, roots, husks and grains and the effect was further increased with exogenous MT combined with NPs in a dose-additive way. 50 and 100 mg/kg ZnONPs treatments alone decreased grain Cd by 6.5 %, and 20 % and increased the Zn concentration by 20.1 % and 24 % than control. 100 mg/kg ZnONPs +100 μM MT treatment decreased the grain Cd by 63.5 % and increased grain Zn by 51 % than control treatment. Total Cd uptake (tissues biomass × Cd concentration in respective tissues) in shoots, roots, husks and grains increased with ZnONPs alone or combined with MT than control whereas soil post-harvest bioavailable Cd concentration decreased with treatments than control. The Cd reduction in grains was due to increase in biomass and Zn concentration thereby decreasing bioavailable Cd in soil and its accumulation in plants. This study suggested that combined use of ZnONPs and MT may provide new approaches for minimizing Cd and biofortification of Zn in edible parts of plants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Chitosan (CS)/metal oxide (MO) nano-carriers have recently attracted attention due to their great integration into several biomedical applications. Herein, CS and dysprosium oxide based bio-nanocomposites (Dy 2 O 3 /CuFe 3 O 4 /CS) were prepared using a citrate sol-gel route for biomedical settings at large and drug delivery, in particular. The chemical structure, average crystallite size, and surface morphology of Dy 2 O 3 /CuFe 3 O 4 /CS bio-nanocomposites were characterized using spectroscopic techniques, including FT-IR, PXRD, and SEM. The prepared nano composite's drug loading or release kinetics were investigated by FT-IR, zeta potential (ZP), and ultraviolet-visible spectroscopy (UV-Vis). In the FT-IR spectrum, the peaks in the range of 800-400 cm -1 confirmed the formation of meta-oxides, while amide bands at 1661 and 1638 cm -1 revealed the existence of CS in the bio-nanocomposite. The peaks at 2θ = 35.46 and 28.5, 39.4 indicated the presence and chemical interaction of Dy 2 O 3 and CuFe 3 O 4, respectively. The crystallite size was <20 nm. The model drug used in the loading and in vitro release assays was ciprofloxacin hydrochloride. Ciprofloxacin's CF stretch caused a modest peak to be seen at 1082 cm -1 and changed in zeta potential value from 7.90 mV to 8.88 mV endorsing that the drug had been loaded onto the nanomaterial. The loading efficiency (%) of CIP onto the composite was from 25 to 30 %, calculated from optical density measurements. Different kinetic models, such as zero-order, first-order, Higuchi, Hixon-Crowell, and Korsmeyer-Peppas, were determined to confirm the drug release mechanism. The percent (%) of drug release from the surface of Dy 2 O 3 /CuFe 3 O 4 /CS in PBS (pH 7.4), acidic (pH 2.2) and basic (pH 9.4) dissolution media were found to be 70, 28 and 20 %, respectively. Drug kinetics showed that mainly the release is fickian type followed "Fick's law of diffusion", slightly deviated from fickian release (dissolution-dependent system). Korsmeyer-Peppas (R 2 0.9773, n < 0.4) and Higuchi's (R 2 0.9846) models were the best for fitting controlled drug release data. The results revealed that the Dy 2 O 3 /CuFe 3 O 4 /CS bio-nanocomposite has good potential for a controlled drug delivery system., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The present study aims to formulate the characterization and distribution of microplastic in the estuarine surface sediments of Kayamkulam estuary, southwest coast of India. The sediments were dominated by fibre and film shaped microplastic substances. The surface sediments were dominated by <1000 μm microplastics. The composition of microplastics in descending order was as follows: polyester > polypropylene > polyethylene. The distribution of microplastics was significantly higher than that observed in the other study regions, except for Pearl river estuary and Guanabara Bay. The distribution of microplastics was chiefly controlled by estuarine inundating water and the distance of the sampling site from the open sea., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Element concentration (Fe, Mn, Pb, Zn, Cu, Cr, Ni and Co) in the surface sediments of Ashtamudi estuary, Southwest coast of India, has been analyzed to understand the spatial variation and potential ecological risk status. The sediment pollution index and Potential Ecological Risk index suggest that the northeastern part of the estuary exhibits low to moderate polluted sediments with moderate ecological risk. The results of correlation analysis indicate that the natural weathering process and river input play an important role in the distribution of the elements in the surface sediments of the estuary. The extracted factor results indicate that the fine sediment fractions supporting for accumulation of the trace elements, whereas the enriched level of Fe and Mn is chiefly controlled by the riverine process, and other elements are contributed by anthropogenic influences., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Bugs, such as microorganisms and insects, are present in the environment and sometimes can be health-hazardous if the living environment is not maintained following proper hygienic regulations. In the present scenario of increasing public awareness, environmental consciousness, and growing demand for easy-care, and disinfected textiles, the manufacturing of protective and easy-to-care textiles has become a key necessity of the modern world. Comfortable, clean, hygienic, antimicrobial, and insect repelling properties of textile goods are gaining the accelerating research momentum as a basic requirement to produce multifunctional textiles. These functional finishes have numerous applications such as in-home textiles, bed nets, and tenting, camping gear as well as in military uniforms. Synthetic antimicrobial and insect repellents are quite effective against insects and microscopic organisms but are slightly toxic to the human being and the environment. To overcome these problems, researchers are considering natural agents for functional finishes, but their effectiveness is less durable to textile material. Besides needful advantages, the excessive use of dyes in finishing processes heavily required washing cycles and ultimately release various types of hazardous dyes or wasteful effluents in the environment. This review reports the chemical composition and recent developments in textile finishes, particularly antimicrobial and insect repellent textile finishes. A large number of commonly used antimicrobial agents (i.e. chitosan, zwitterionic compounds, silver and silver-based compounds, titanium dioxide nanoparticles, imidazolium salts, triclosan and quaternary ammonium salts) and insect repellent textile finishes (i.e. N‑N‑diethyl‑m‑toluamide, permethrin, cypermethrin, pyrethrum, picaridin, bioallethrin, citriodiol and essential oils) have been presented. Finally, the review is wrapped up with major research gaps/challenges, concluding remarks, and future opportunities in this area of research., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Nanoparticle (NP) effects in a biological system are driven through the formation and structure of the protein corona-NP complex, which is dynamic by nature and dependent upon factors from both the local environment and NP physicochemical parameters. To date, considerable data has been gathered regarding the structure and behavior of the protein corona in blood, plasma, and traditional cell culture medium. However, there exists a knowledge gap pertaining to the protein corona in additional biological fluids and following incubation in a dynamic environment. Using 13nm gold NPs (AuNPs), functionalized with either polyethylene glycol or tannic acid, we demonstrated that both particle characteristics and the associated protein corona were altered when exposed to artificial physiological fluids and under dynamic flow. Furthermore, the magnitude of observed behavioral shifts were dependent upon AuNP surface chemistry. Lastly, we revealed that exposure to interstitial fluid produced protein corona modifications, reshaping of the nano-cellular interface, modified AuNP dosimetry, and induction of previously unseen cytotoxicity. This study highlights the need to elucidate both NP and protein corona behavior in biologically representative environments in an effort to increase accurate interpretation of data and transfer of this knowledge to efficacy, behavior, and safety of nano-based applications., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: The purpose of this study was to determine the diagnostic performance of magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis during pregnancy in a multiinstitutional study., Study Design: In this multicenter retrospective study, the cases of pregnant women who underwent MRI evaluation of abdominal or pelvic pain and who had clinical suspicion of acute appendicitis between June 1, 2009, and July 31, 2014, were reviewed. All MRI examinations with positive findings for acute appendicitis were confirmed with surgical pathologic information. Sensitivity, specificity, negative predictive values, and positive predictive values were calculated. Receiver operating characteristic curves were generated, and area under the curve analysis was performed for each participating institution., Results: Of the cases that were evaluated, 9.3% (66/709) had MRI findings of acute appendicitis. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive values were 96.8%, 99.2%, 99.0%, 92.4%, and 99.7%, respectively. There was no statistically significant difference between centers that were included in the study (pair-wise probability values ranged from 0.12-0.99)., Conclusion: MRI is useful and reproducible in the diagnosis of suspected acute appendicitis during pregnancy., (Published by Elsevier Inc.)

Due to their distinctive physiochemical properties, including a robust antibacterial activity and plasmonic capability, hundreds of consumer and medical products contain colloidal silver nanoparticles (AgNPs). However, even at sub-toxic dosages, AgNPs are able to disrupt cell functionality, through a yet unknown mechanism. Moreover, internalized AgNPs have the potential to prolong this disruption, even after the removal of excess particles. In the present study, we evaluated the impact, mechanism of action, and continual effects of 50 nm AgNP exposure on epidermal growth factor (EGF) signal transduction within a human keratinocyte (HaCaT) cell line. After AgNP expose, EGF signaling was initially obstructed due to the dissolution of particles into silver ions. However, at longer durations, the internalized AgNPs increased EGF signaling activity. This latter behavior correlated to sustained HaCaT stress, believed to be maintained through the continual dissolution of internalized AgNPs. This study raises concerns that even after exposure ceases, the retained nanomaterials are capable of acting as a slow-release mechanism for metallic ions; continually stressing and modifying normal cellular functionality., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Copper (Cu(2+)) containing wastewaters are extensively released from different industries and its excessive entry into food chains results in serious health impairments, carcinogenicity and mutagenesis in various living systems. An array of technologies is in use to remediate Cu(2+) from wastewaters. Adsorption is the most attractive option due to the availability of cost effective, sustainable and eco-friendly bioadsorbents. The current review is dedicated to presenting state of the art knowledge on various bioadsorbents and physico-chemical conditions used to remediate Cu(2+) from waste streams. The advantages and constraints of various adsorbents were also discussed. The literature revealed the maximum Cu adsorption capacities of various bioadsorbents in the order of algae>agricultural and forest>fungal>bacterial>activated carbon>yeast. However, based on the average Cu adsorption capacity, the arrangement can be: activated carbon>algal>bacterial>agriculture and forest-derived>fungal>yeast biomass. The data of Cu removal using these bioadsorbents were found best fit both Freundlich and Langmuir models. Agriculture and forest derived bioadsorbents have greater potential for Cu removal because of higher uptake, cheaper nature, bulk availability and mono to multilayer adsorption behavior. Higher costs at the biomass transformation stage and decreasing efficiency with desorption cycles are the major constraints to implement this technology., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Due to their unique properties, gold nanorods (GNRs) have shown tremendous potential for advancing bio-imaging and sensing applications. As these nanoparticles display size-dependent optical properties, high aspect ratio GNRs are of particular interest for these applications because of their increased scattering contrast. While studies are emerging that demonstrate successful synthesis of high aspect ratio GNRs, their behavior and fate in a physiological environment has yet to be investigated. The goal of this study was to evaluate the rate of cellular internalization and cytotoxicity of long GNRs (aspect ratio 32) in a human keratinocyte cell line. Additionally, the critical role of surface chemistry in extent of cellular interactions and cytotoxicity was evaluated. Through comparison with aspect ratio 3 GNRs, it was identified that high aspect ratio GNRs displayed enhanced cellular internalization. Furthermore, surface functionalization dictated the quantity of GNRs internalized, with tannic acid having a significant increase over polyethylene glycol. However, the augmented intracellular concentration identified with long, tannic acid GNRs resulted in a considerable degree of cytotoxicity, which was not associated with other GNR conditions. Therefore, while the inclusion of high aspect ratio GNRs may increase the capabilities for nano-based applications, there exist some unintentional toxicological consequences that must also be considered., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Background: CYP1A1, CYP2A6 and CHRNA5 are biologically plausible genes as risk factors for lung cancer but no studies have been reported in the Bangladeshi population., Methods: We conducted this study to determine the prevalence and role of CYP1A1, CYP2A6 and CHRNA5 polymorphisms together with tobacco smoking in the development of lung cancer in Bangladesh. A case-control study was carried out on 106 lung cancer patients and 116 controls to investigate three allelic variants of the CYP1A1 gene-rs4646903, rs1048943 and rs1799814; 2 variants of CYP2A6 (CYP2A6*1B1, CYP2A6*4) and 1 variant of CHRNA5 (rs16969968) using Polymerase Chain Reaction Restriction Fragment Length Polymorphism., Results: Lung cancer risk was estimated as odds ratio (OR) and 95% confidence interval (CI) using unconditional logistic regression models adjusting for age, sex and smoking. A significantly elevated lung cancer risk was associated with heterozygous, mutant and combined heterozygous plus mutant variants of CYP1A1 rs4646903. A significant association was also found for heterozygous and heterozygous plus mutant variants of rs1048943 which was in linkage disequilibrium with rs4646903. The risk of lung cancer was decreased significantly in individuals carrying at least one CYP2A6 deletion (CYP2A6*4) allele. No association with lung cancer risk was found for CHRNA5 rs16969968. When stratified by smoking, the effects of CYP1A1 and CYP2A6 polymorphisms on lung cancer susceptibility were found to be significant only in heavy smokers who had smoked 40 pack years or more (54% of all cases) but no associations were seen for lighter smokers. No association was also found with any polymorphism in the non-smokers in this study., Conclusions: Our results indicate that the CYP1A1*2B allele (rs4646903 and rs1048943) is associated with an increased lung cancer risk and CYP2A6*4 is associated with a decreased lung cancer risk in the study population., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The growth of the nanotechnology industry and subsequent proliferation of nanoparticle types present the need to rapidly assess nanoparticle toxicity. We present a novel, simple and cost-effective nebulizer-based method to deliver nanoparticles to the Drosophila melanogaster respiratory system, for the purpose of toxicity testing. FluoSpheres, silver, and CdSe/ZnS nanoparticles of different sizes were effectively aerosolized, showing the system is capable of functioning with a wide range of nanoparticle types and sizes. Red fluorescent CdSe/ZnS nanoparticles were successfully delivered to the fly respiratory system, as visualized by fluorescent microscopy. Silver coated and uncoated nanoparticles were delivered in a toxicity test, and induced Hsp70 expression in flies, confirming the utility of this model in toxicity testing. This is the first method developed capable of such delivery, provides the advantage of the Drosophila health model, and can serve as a link between tissue culture and more expensive mammalian models in a tiered toxicity testing strategy.

This study was undertaken to determine whether silver nanoparticles (Ag-45 nm NPs) induce selective and specific biological effects, such as induction of proliferation and nitric oxide (NO) production, and cytotoxicity in coronary endothelial cells (CECs), and regulation of vascular tone in isolated rat aortic rings. Physical characterization of Ag-45 nm NPs by transmission electron microscopy (TEM) demonstrated that nanoparticles ranging in size from 10 to 90 nm had biological effects on CECs. Increasing concentrations of Ag-45 nm NPs exerted a dual effect on cell proliferation whereby proliferation was inhibited at low concentrations of NPs and stimulated at high concentrations. The effects of high, but not low, concentrations of Ag-45 nm NPs were dependent on NO because the effects were partially blocked by N(G)-nitro-L-arginine methyl ester (L-NAME). We have also shown that high, but not low, concentrations of Ag-45 nm NPs induce NO-dependent proliferation through activation of endothelial nitric oxide synthase (eNOS) by phosphorylation of Serine 1177. Moreover, the antiproliferative and proliferative effects of Ag-45 nm NPs were concentration-dependent and inversely correlated with cellular toxicity. In isolated rat aortic rings, a low concentration of NPs induced vasoconstriction and a high concentration stimulated vasodilation. The physiologic effects induced by a low concentration of Ag-45 nm NPs inhibited acetylcholine- (ACh-) induced NO-mediated relaxation. Vasodilation induced by a high concentration of NPs was partially abolished by L-NAME pretreatment. When the endothelium was removed from the rings, all physiologic responses were blocked. These results clearly demonstrate that the NPs have selective and specific effects on the vascular endothelium in a concentration-dependent manner and suggest that opposite effects could be associated with NPs of different sizes.

Nanomaterials have novel properties and functions because of their small size. The unique nature of nanomaterials may be associated with potentially toxic effects. The aim of this study was to evaluate the in vivo genotoxicity of rats exposed with Aluminum oxide nanomaterials. Hence in the present study, the genotoxicity of Aluminum oxide nanomaterials (30 and 40 nm) and its bulk material was studied in bone marrow of female Wistar rats using chromosomal aberration and micronucleus assays. The rats were administered orally with the doses of 500, 1000 and 2000 mg/kg bw. Statistically significant genotoxicity was observed with Aluminum oxide 30 and 40 nm with micronucleus as well as chromosomal aberration assays. Significantly (p < 0.05 or p < 0.001) increased frequency of MN was observed with 1000 and 2000 mg/kg bw dose levels of Aluminum oxide 30 nm (9.4 +/- 1.87 and 15.2 +/- 2.3, respectively) and Aluminum oxide 40 nm (8.1 +/- 1.8 and 13.9 +/- 2.21, respectively) over control (2.5 +/- 0.7) at 30 h. Likewise, at 48 h sampling time a significant (p < 0.05 or p < 0.001) increase in frequency of MN was evident at 1000 and 2000 mg/kg bw dose levels of Aluminum oxide 30 nm (10.6 +/- 1.68 and 16.6 +/- 2.66, respectively) and Aluminum oxide 40 nm (9.0 +/- 1.38 and 14.7 +/- 1.68, respectively) compared to control (1.8 +/- 0.75). Significantly increased frequencies (p < 0.05 or p < 0.001) of chromosomal aberrations were observed with Aluminum oxide 30 nm (1000 and 2000 mg/kg bw) and Aluminum oxide 40 nm (2000 mg/kg bw) in comparison to control at 18 and 24 h. Further, since there is need for information on the toxicokinetics of nanomaterials, determination of these properties of the nanomaterials was carried out in different tissues, urine and feces using inductively coupled plasma mass spectrometry (ICP-MS). A significant size dependent accumulation of Aluminum oxide nanomaterials occurred in different tissues, urine and feces of rats as shown by ICP-MS data. The results of our study suggest that exposure to Aluminum oxide nanomaterials has the potential to cause genetic damage.

Nanoparticles are small scale substances (<100 nm) used in biomedical applications, electronics, and energy production. Increased exposure to nanoparticles being produced in large-scale industry facilities elicits concerns for the toxicity of certain classes of nanoparticles. This study evaluated the effects of silver-25 nm (Ag-25) nanoparticles on gene expression in different regions of the mouse brain. Adult-male C57BL/6N mice were administered (i.p.) 100mg/kg, 500 mg/kg or 1,000 mg/kg Ag-25 and sacrificed after 24h. Regions from the brain were rapidly removed and dissected into caudate nucleus, frontal cortex and hippocampus. Total RNA was isolated from each of the three brain regions collected and real-time RT-PCR analysis was performed using Mouse Oxidative Stress and Antioxidant Defense Arrays. Array data revealed the expression of genes varied in the caudate nucleus, frontal cortex and hippocampus of mice when treated with Ag-25. The data suggest that Ag-25 nanoparticles may produce neurotoxicity by generating free radical-induced oxidative stress and by altering gene expression, producing apoptosis and neurotoxicity.

Efficacy and safety of antibiotic 'locks', in prevention of thrombotic and infectious complication-related morbidity and mortality, among diabetics dialyzed through tunneled-cuffed catheters (TCCs) has not been effectively investigated. This trial was designed to investigate the outcome of TCCs (n = 109), inserted among 96 diabetic end-stage renal disease patients (March 2002-February 2003), by comparing the catheter thrombosis, catheter-related bloodstream infections (CRBSI), catheter survival, and mortality rates, between the cohorts of 49 patients who had TCCs (n = 51) 'locked' with cefotaxime/heparin (group I) and 47 patients with TCCs (n = 58) filled with standard heparin (group II). Thrombosis was defined as the inability to use catheter at a blood flow of 200 ml/min despite intraluminal thrombolysis. Primary end points were catheter thrombosis and CRBSI; elective catheter removal and CRBSI-related death led to sensor of TCCs follow-up. Patients with intraluminal cefotaxime/heparin lock, on cumulative survival analysis, showed a superior thrombosis-free (86.3 vs 63.8%, P = 0.023, log rank), infection-free (72.9 vs 27.1%, P = 0.004, log rank), and thrombosis- and infection-free TCC survival (78.4 vs 37.9%, P = 0.001, log rank) at 365 days, besides having significantly lower incidence of CRBSI (1.56 vs 3.68 episodes/1000 catheter days, P < 0.0001) and CRBSI-related mortality (9.8 vs 23.4%, P = 0.015), compared with the heparin-alone group. Deployment of cefotaxime-heparin 'lock' enhances catheter survival; reduces thrombotic and infectious complications and ensuing mortality, among diabetics on dialysis. However, further studies are needed to define the long-term implications of antibiotic locks in terms of the risk of emergence of antimicrobial resistance.

Formalin administered (15 and 20 mL) into the crops of White Leghorn cockerels resulted in behavioral alterations, included depression, dullness, staggering, somnolence, anorexia, and decreased frequency of crowing. A significant decrease was observed in red blood cell counts, hemoglobin concentration, packed cell volume, and leukocyte counts in birds fed higher levels of formalin. Decreasing and increasing trends in concentrations of serum proteins and enzymes, respectively, were observed with increases in formalin doses. Significantly lower blood glucose and testosterone levels and significantly (P < 0.05) higher blood urea and creatinine concentrations were observed in birds fed higher formalin levels. No gross or microscopic lesions were observed in the birds fed different levels of formalin mixed in feed. These changes suggested that the formalin mixed in feed might have evaporated, and, hence, the amount ingested might have been too low to induce pathological changes. It was concluded from the present study that formalin mixed up to 5 mL/kg of feed, corresponding to 10 mL/bird of 3% formalin in drinking water by crop tube had no adverse effects on the health of White Leghorn cockerels.

We examined changes in practice patterns after the establishment of a varicose vein center (VVC) within two tertiary university vascular surgery practices and compared differences between urban (U) and rural (R) sites. Practice patterns for the treatment of VVs were compared 3 years before (period 1) and 3 years after (period 2) the formation of a U-VVC and an R-VVC in 2001. Both VVCs were part of similar-sized tertiary vascular surgery practices. Evaluation was specific to VVs, reticular veins, and telangiectasias. Prior to U-VVC, there were 338 office visits, six office procedures, and 114 hospital procedures. After U-VVC, there were 624, 120, and 312, respectively. Prior to R-VVC, there were 85 office visits, five office procedures, and 69 hospital procedures. After R-VVC, there were 528, 163, and 303, respectively. In period 1 for U-VVC and R-VVC, VVC relative value unit (RVU) generation as a percent of total practice RVUs was 1.0% and 0.7%, respectively. In period 2 for U-VVC and R-VVC, VVC RVU generation as a percent of total practice RVUs was 2.6% and 2.5%, respectively. In an effort to provide more coordinated treatment for patients with VVs, establishing a VVC within a tertiary academic vascular surgery practice can lead to rapid expansion of clinical volume by increased office visits, office procedures, and hospital procedures. Clinical demand for evaluation and treatment of VVs showed little variation between R-VVC and U-VVC.

Purpose: To determine intraobserver and interobserver variability of carotid arteriography interpretation as well as the reliability of simple visual interpretation (SVI) or "eyeballing" of arteriography in the measurement of internal carotid artery stenoses., Methods: Intraobserver and interobserver measurements of 200 carotid arteriograms were performed in a blinded fashion by two vascular surgeons (VS1 and VS2) using a digital caliber computer program similar to software available in catheterization laboratories. The distal normal internal carotid artery was used as a frame of reference. These computer-derived measurements were compared with previous SVI measurements, found by retrospective chart review, that were performed at the initial time of arteriography., Results: Intraobserver agreement (VS1a vs VS1b and VS2a vs VS2b) within +/-5% using the computer program was 94% and 92%. Interobserver agreement within +/-5% using the computer program for the four possible combinations ranged from 43% to 48%. Interobserver agreement using the computer program increased to 83% to 88% for correct stenosis interpretation within +/-20%. In the 16% to 49% category (by computer measurement), SVI would have placed the stenosis in a higher category 40% to 56% of the time. Likewise, in the 50% to 79% category, comparing SVI with the four different computer caliber measurements, SVI overestimated the stenosis to the 80% to 99% category by 30% to 44%. In the 80% to 99% category, SVI overestimated lesions in 27% to 51% of the cases. All occlusions seen on SVI correlated with computer program measurements. The computer readings in many cases downgraded the degree of carotid stenosis into a lower category and in some cases, may have led to a different treatment paradigm. SVI never underestimated carotid stenosis compared with all matched computer program measurements., Conclusions: Compared with a method of objective measurement similar to that used in a catheterization laboratory, SVI overestimated most carotid artery stenoses. Given the coming era of carotid stenting and a renewed need for arteriography before carotid intervention, knowledge of variability and correct interpretation of carotid stenosis using available technology remains paramount to warranted treatment.

The solution properties of nickel complex with 4-(2'-benzo-thiazolylazo) salicylic acid (BTAS) have been studied by zero-order absorption spectrophotometry in 40% (v/v) ethanol at 20 degrees C and an ionic strength of 0.1 mol dm(-3) (KNO(3)). The equilibria that exist in solution were established and the basic characteristics of complexes formed were determined. A new direct spectrophotometric method for the determination of trace amounts of the nickel is proposed based on the formation of the Ni (BTAS) complex at pH 7.0. The absorption maximum, molar absorbtivity, and Sandell's sensitivity of 1:1 (M:L) complex are 525 nm, 0.6 x 10(4) l mol(-1) cm(-1) and 2.824 x 10(-9) microg cm(-2), respectively. The use of first-derivative spectrophotometry eliminates the interference of iron and enables the simultaneous determination of nickel and iron using BTAS. Quantitative determination of Ni(II) and Fe(III) is possible in the range (0.59-7.08) and (2.1-8.4) microg ml(-1), respectively with a relative standard deviation of 0.5%. The proposed method has been successfully applied to the simultaneous spectrophotometric determination of nickel and iron in steel alloys and aluminum alloys.

Background: Management of postcardiotomy cardiogenic shock with a ventricular assist device (VAD) is a common and accepted therapeutic option. However, VAD use in patients with mechanical heart valves (MHVs) is thought to carry an increased risk of thromboembolus. We report a series of 7 patients with combined VAD-MHV and review the literature., Methods: A retrospective review was performed on all patients who were supported with a ventricular assist device with a mechanical heart valve in place. A literature review was also performed from 1966 to 2000., Results: Seven patients were identified from April 1988 to June 2000 as having VAD support with a MHV. One thromboembolic event was documented in the 7 patients (14%). Five of the 7 patients (71%) underwent VAD explantation. Overall survival rate was 3 of 7 (43%). Causes of death included heart failure, renal failure, multisystem organ failure, adult respiratory distress syndrome, and cerebral hypoxia. All patients who died had support withdrawn at the request of the family. All patients discharged are currently alive with length of survival of 3, 26, and 84 months., Conclusions: This study suggests that this population's rate of survival to discharge and risk of thromboembolus compare favorably to that of the general VAD population. We believe that anticoagulation can be managed as with any MHV patient and that flow rates can be kept slightly lower, which may encourage valve washing.

Hydrazine is an aircraft fuel and propellant used by the US Air Force. Due to its toxicity the Propulsion Directorate of the Air Force Research Laboratory (AFRL/PR) has investigated alternative chemicals to replace hydrazine. AFRL/PR has synthesized a series of high energy chemicals (HECs), primarily hydrazine derivatives and amino containing compounds such as hydrazinium nitrate (HZN), 2-hydroxyethyl-hydrazine nitrate (HEHN), diethyl hydrazine nitrate (DEHN), ethanolamine nitrate (EAN), histamine dinitrate (HDN) and methoxylamine nitrate (MAN) to study as alternative chemical candidates. Although HECs are reliable constituents of powered propellant systems, they constitute an important class of toxic agents to which military and civilian personnel can be exposed. The current study was undertaken to examine the toxicity of HECs in primary hepatocytes in vitro. The effects of short-term exposure (4 h) of hepatocytes to HECs were investigated with reference to viability, mitochondrial function and oxidative stress markers. The results showed a decrease in mitochondrial activity, increase in lactate dehydrogenase (LDH) leakage and depletion of reduced glutathione (GSH) levels. The levels of reactive oxygen species (ROS) increased dose dependently in HZN, MAN and HDN exposed cells. However, there was no induction of ROS generation in EAN, DEHN and HEHN exposed cells. Depletion of GSH in hepatocytes by buthionine sulfoximine (BSO) prior to exposure to HZN increased its toxicity. The results suggest that at least one mechanism of HEC toxicity is mediated through oxidative stress.

Vasoactive drugs were infused through catheters in the right atrium and then the left atrium of 34 patients who required either vasopressor or vasodilator support following cardiac operation to determine if the route of infusion affected the aortic blood concentration of these agents. Drugs were given through the right atrium for one hour and then the left atrium for an hour. Both central aortic and pulmonary arterial blood were assayed for drug concentrations, and hemodynamic measurements were made. Sixteen patients receiving dopamine hydrochloride through the left atrium had a 36 +/- 12% (+/- standard error of the mean) increase in aortic concentration of the drug (p less than 0.005) and a 37 +/- 14% increase in cardiac index (p less than 0.005) compared with administration through the right atrium. Seven patients receiving epinephrine showed a 59 +/- 21% increase in aortic concentration (p less than 0.05) and a 21 +/- 10% increase in cardiac index (p greater than 0.05, not significant). Eleven patients receiving sodium nitroprusside achieved a 99 +/- 25% increase in aortic concentration (p less than 0.005) and a 20 +/- 7% increase in cardiac index (p less than 0.05). In all instances, significantly higher central aortic blood concentrations were achieved during left atrial (LA) versus right atrial (RA) infusions. Changes in blood concentration of the drug between the pulmonary artery and the aorta during RA infusion suggest removal or inactivation of these drugs in the pulmonary vasculature.(ABSTRACT TRUNCATED AT 250 WORDS)

Subendocardial resection is performed in patients with ventricular tachycardia (VT), but its efficacy as related to the site of origin of VT is problematic. We analyzed the efficacy of subendocardial resection in 24 patients with coronary artery disease and VT. All patients underwent preoperative and intraoperative mapping before subendocardial resection. Postoperative electrophysiologic studies were performed in the drug-free state 7 to 14 days after subendocardial resection. Group 1 (n = 14) had anterior, septal, or lateral sites of origin, and Group 2 (n = 10) had inferior or posterior sites of origin. Localization of presystolic electrical activity during VT by preoperative and intraoperative mapping was comparable in both groups (100%). Resectability of the site of origin was higher in Group 1. Induction of VT during a postoperative electrophysiological study was higher in Group 2. Perioperative mortality was comparable. Postoperative antiarrhythmic therapy was instituted more frequently in Group 2. Actuarial survival analysis showed improved patient survival at one year after subendocardial resection for both groups. The efficacy of subendocardial resection is related to site of origin of VT: Subendocardial resection is less efficacious in VT with inferior or posterior sites of origin because of nonresectability of the arrhythmogenic area.