Highly selective transport of mercury(II) ion through a bulk liquid membrane

In this work carrier-facilitated transport of mercury(II) against its concentration gradient from aqueous 0.04 M hydrochloric acid solution across a liquid membrane containing isopropyl 2-[(isopropoxycarbothiolyl)disulfanyl]ethane thioate (IIDE) as the mobile carrier in chloroform has been investigated. Sodium thiocyanate solution (1.6 M) was the most efficient receiving phase agent among several aqueous reagents tested. Various parameters such as investigated. Under optimum conditions the transport of Hg(II) across the liquid membrane is more than 97% after 2.5 h. The carrier, IIDE, selectively and efficiently could able to transport Hg (II) ions in the presence of other associated metal ions in binary systems.

Dispersive liquid-liquid microextraction based on solidification of floating organic drop for simultaneous separation/preconcentration of nickel, cobalt and copper prior to determination by electrothermal atomic absorption spectrometry

A dispersive liquid-liquid microextraction based on solidification of floating organic drop for simultaneous extraction of trace amounts of nickel, cobalt and copper followed by their determination with electrothermal atomic absorption spectrometry was developed. 300 µL of acetone and 1-undecanol was injected into an aqueous sample containing diethyldithiocarbamate complexes of metal ions. For a sample volume of 10 mL, enrichment factors of 277, 270 and 300 and detection limits of 1.2, 1.1 and 1 ng L-1 for nickel, cobalt and copper were obtained, respectively. The method was applied to the extraction and determination of these metals in different water samples.

Ni(II), Cu(II), AND Zn(II) COMPLEXES DERIVED FROM A NEW SCHIFF BASE 2-((Z)-(3-METHYLPYRIDIN-2- YLEIMINO)METHYL)PHENOL AND SYNTHESIS OF NANO SIZED METAL OXIDE PARTICLES FROM THESE COMPOUNDS

Synthesis, spectral identification, and magnetic properties of three complexes of Ni(II), Cu(II), and Zn(II) are described. All three compounds have the general formula [M(L)2(H2O)2], where L = deprotonated phenol in the Schiff base 2-((z)-(3-methylpyridin-2-yleimino)methyl)phenol. The three complexes were synthesized in a one-step synthesis and characterized by elemental analysis, Fourier transform infrared spectroscopy, electronic spectra, X-ray diffraction (XRD), and room temperature magnetic moments. The Cu(II) and Ni(II) complexes exhibited room temperature magnetic moments of 1.85 B.M. per copper atom and 2.96 B.M. per nickel atom. The X-band electron spin resonance spectra of a Cu(II) sample in dimethylformamide frozen at 77 K (liquid nitrogen temperature) showed a typical ΔMS = ± 1 transition. The complexes ([M(L)2(H2O)2]) were investigated by the cyclic voltammetry technique, which provided information regarding the electrochemical mechanism of redox behavior of the compounds. Thermal decomposition of the complexes at 750 ºC resulted in the formation of metal oxide nanoparticles. XRD analyses indicated that the nanoparticles had a high degree of crystallinity. The average sizes of the nanoparticles were found to be approximately 54.3, 30.1, and 44.4 nm for NiO, CuO, and ZnO, respectively.

Uniformity of liquid distribution in the canopy of the bean plant, using the spectrophotometric analysis

Fungal diseases are important factors limiting common bean yield. White mold is one of the main diseases caused by soil pathogens. The objective of this study was to quantify the distribution of a fungicide solution sprayed into the canopy of bean plants by spectrophotometry, using a boom sprayer with and without air assistance. The experiment was arranged in a 2 x 2 x 2 factorial (two types of nozzles, two application rates, and air assistance on and off) randomized block design with four replications. Air assistance influenced the deposition of solution on the bean plant and yield increased significantly with the increased rate of application and air assistance in the boom sprayer.

Heavy metal toxicity in rice and soybean plants cultivated in contaminated soil

Heavy metals can accumulate in soil and cause phytotoxicity in plants with some specific symptoms. The present study evaluated the specific symptoms on rice and soybeans plants caused by excess of heavy metals in soil. Rice and soybean were grown in pots containing soil with different levels of heavy metals. A completely randomized design was used, with four replications, using two crop species and seven sample soils with different contamination levels. Rice and soybean exhibited different responses to the high concentrations of heavy metals in the soil. Rice plants accumulated higher Cu, Mn, Pb and Zn concentrations and were more sensitive to high concentrations of these elements in the soil, absorbing them more easily compared to the soybean plants. However, high available Zn concentrations in the soil caused phytotoxicity symptoms in rice and soybean, mainly chlorosis and inhibited plant growth. Further, high Zn concentrations in the soil reduced the Fe concentration in the shoots of soybean and rice plants to levels considered deficient.

Sugar content in liquid oral medicines for children

The most sold and/or prescribed liquid oral medicines for children in Tubarão, Southern Brazil, were assessed. Their sugar concentration was tested and compared to those in their directions for use. All pharmacies and pediatricians working in the city were visited by a previously trained interviewer. Pre-tested questionnaires were applied in order to assess the most sold pediatric as well as the most prescribed pediatric liquid oral medicines. Three samples of each medicine were analyzed by Lane-Eynon general volumetric method. Among the 14 most sold/prescribed medicines only four did not have sugar contents (analgesic, cortisone, and syrups). Sugar concentration ranged from 8.59 g/100 g of drug (SD=0.29 g/100 g) to 67.0 g/100 g of drug (SD=6.07 g/100 g). Only 50.0% of the total medicines that presented sugar in their ingredients showed this information in their directions.

Comparative evaluation of adverse effects in the use of powder trivalent antivenom and liquid antivenoms in Bothrops snake bites

INTRODUCTION: Snake bite, a problem in public health, generally occurs where there is no electric power. METHODS: A comparative clinical study was conducted with 102 victims of Bothrops snake bite, from the state of Amazonas, Brazil; 58 victims were treated with liofilizated trivalent antivenom serum (SATL) and 44 victims treated with liquid bivalent and monovalent antivenom serum (SAMBL). RESULTS: 17% (10/58) of patients presented adverse effects with the SATL and 25% (11/44) with the SAMBL. CONCLUSIONS: There was no statistic difference in number of adverse effects between the two types of snake bite antivenom.

Vancomycin monitoring in term newborns: comparison of peak and trough serum concentrations determined by high performance liquid chromatography and fluorescence polarization immunoassay

INTRODUCTION: Peak and trough serum concentrations of vancomycin were determined in term newborn infants with confirmed or suspected Staphylococcus sp sepsis by high performance liquid chromatography and flourescence polarization immunoassay. OBJECTIVE: To statistically compare the results of the high performance liquid chromatography and flourescence polarization immunoassay techniques for measuring serum vancomycin concentrations. METHODS: Eighteen peak and 20 trough serum samples were assayed for vancomycin concentrations using high performance liquid chromatography and flourescence polarization immunoassay from October 1995 to October 1997. RESULTS: The linear correlation coefficients for high performance liquid chromatography and flourescence polarization immunoassay were 0.27 (peak, P = 0.110) and 0.26 (trough, P = 0.1045) respectively, which were not statistically significant. CONCLUSION: There was wide variation in serum vancomycin concentrations determined by high performance liquid chromatography as compared with those determined by flourescence polarization immunoassay. There was no recognizable pattern in the variability; in an apparently random fashion, the high performance liquid chromatography measurement was sometimes substantially higher than the flourescence polarization immunoassay measurement, and at other times it was substantially lower.

Intervenção coronária percutânea utilizando Full Metal Jacket com stents farmacológicos: eventos cardíacos adversos maiores em um ano

FUNDAMENTO: O benefício clínico de intervenção coronária percutânea (ICP) para lesões coronárias longas é incerto; além disso, foram levantadas dúvidas questões sobre a sua segurança. OBJETIVO: Avaliar os preditores de eventos cardíacos adversos maiores (ECAM) associados à ICP utilizando Full Metal Jacket (FMJ), definido como a sobreposição de stents farmacológicos (SF) medindo >60 mm de comprimento, para lesões muito longas. MÉTODOS: Foram incluídos 136 pacientes consecutivos com lesões coronárias longas, requerendo FMJ em nosso cadastro de centro único. O desfecho primário incluiu a ocorrência combinada de todas as causas de morte, infarto do miocárdio (IM) e revascularização do vaso alvo (RVA). Variáveis demográficas, clínicas, angiográficas e de procedimento foram avaliadas por meio de análise de regressão de Cox para determinar os preditores independentes de desfecho. RESULTADOS: O comprimento médio do stent por lesão foi de 73,2 ± 12,3 mm e o diâmetro médio do vaso de referência foi de 2,9 ± 0,6 mm. O sucesso angiográfico foi de 96,3%. A ausência de ECAM foi de 94,9% em 30 dias e 85,3% em um ano. No acompanhamento de um ano, a taxa de mortalidade por todas as causas foi de 3,7% (1,5% por mortes cardíacas), a taxa de IM foi de 3,7%, e a incidência de trombose de stent (TS) definitiva ou provável foi de 2,9%. O gênero feminino [risco relativo (RR), 4,40; intervalo de confiança de 95% (IC), 1,81-10,66, p = 0,001) e ICP de artéria coronária não direita (RR, 3,49; p = 0,006; IC 95%, 1,42-8,59) foram preditores independentes de ECAM em um ano. A ausência de eventos adversos em um ano foi maior em pacientes com angina estável submetidos à ICP (RR, 0,33; IC 95% 0,13-0,80, p = 0,014). CONCLUSÕES: A ICP utilizando FMJ com SF para lesões muito longas foi eficaz, mas associada a uma alta taxa de TS em acompanhamento de um ano. No entanto, a taxa de mortalidade cardíaca, IM não relacionado a procedimento, e ECAM foi relativamente baixa. ICP de vaso coronário alvo, apresentação clínica, e gênero feminino são novos fatores clínicos contemporâneos que parecem apresentar efeitos adversos sobre o resultado da ICP utilizando FMJ para lesões longas.

Long-term Outcomes of Drug-eluting versus Bare-metal stent for ST-elevation Myocardial Infarction

Background:Long-term outcomes of drug-eluting stents (DES) versus bare-metal stents (BMS) in patients with ST-segment elevation myocardial infarction (STEMI) remain uncertain.Objective:To investigate long-term outcomes of drug-eluting stents (DES) versus bare-metal stents (BMS) in patients with ST-segment elevation myocardial infarction (STEMI).Methods:We performed search of MEDLINE, EMBASE, the Cochrane library, and ISI Web of Science (until February 2013) for randomized trials comparing more than 12-month efficacy or safety of DES with BMS in patients with STEMI. Pooled estimate was presented with risk ratio (RR) and its 95% confidence interval (CI) using random-effects model.Results:Ten trials with 7,592 participants with STEMI were included. The overall results showed that there was no significant difference in the incidence of all-cause death and definite/probable stent thrombosis between DES and BMS at long-term follow-up. Patients receiving DES implantation appeared to have a lower 1-year incidence of recurrent myocardial infarction than those receiving BMS (RR = 0.75, 95% CI 0.56 to 1.00, p= 0.05). Moreover, the risk of target vessel revascularization (TVR) after receiving DES was consistently lowered during long-term observation (all p< 0.01). In subgroup analysis, the use of everolimus-eluting stents (EES) was associated with reduced risk of stent thrombosis in STEMI patients (RR = 0.37, p=0.02).Conclusions:DES did not increase the risk of stent thrombosis in patients with STEMI compared with BMS. Moreover, the use of DES did lower long-term risk of repeat revascularization and might decrease the occurrence of reinfarction.

Spectral Analysis Related to Bare-Metal and Drug-Eluting Coronary Stent Implantation

Background: The autonomic nervous system plays a central role in cardiovascular regulation; sympathetic activation occurs during myocardial ischemia. Objective: To assess the spectral analysis of heart rate variability during stent implantation, comparing the types of stent. Methods: This study assessed 61 patients (mean age, 64.0 years; 35 men) with ischemic heart disease and indication for stenting. Stent implantation was performed under Holter monitoring to record the spectral analysis of heart rate variability (Fourier transform), measuring the low-frequency (LF) and high-frequency (HF) components, and the LF/HF ratio before and during the procedure. Results: Bare-metal stent was implanted in 34 patients, while the others received drug-eluting stents. The right coronary artery was approached in 21 patients, the left anterior descending, in 28, and the circumflex, in 9. As compared with the pre-stenting period, all patients showed an increase in LF and HF during stent implantation (658 versus 185 ms2, p = 0.00; 322 versus 121, p = 0.00, respectively), with no change in LF/HF. During stent implantation, LF was 864 ms2 in patients with bare-metal stents, and 398 ms2 in those with drug-eluting stents (p = 0.00). The spectral analysis of heart rate variability showed no association with diabetes mellitus, family history, clinical presentation, beta-blockers, age, and vessel or its segment. Conclusions: Stent implantation resulted in concomitant sympathetic and vagal activations. Diabetes mellitus, use of beta-blockers, and the vessel approached showed no influence on the spectral analysis of heart rate variability. Sympathetic activation was lower during the implantation of drug-eluting stents.

Neural Mechanisms and Delayed Gastric Emptying of Liquid Induced Through Acute Myocardial Infarction in Rats

Background: In pathological situations, such as acute myocardial infarction, disorders of motility of the proximal gut can trigger symptoms like nausea and vomiting. Acute myocardial infarction delays gastric emptying (GE) of liquid in rats. Objective: Investigate the involvement of the vagus nerve, α 1-adrenoceptors, central nervous system GABAB receptors and also participation of paraventricular nucleus (PVN) of the hypothalamus in GE and gastric compliance (GC) in infarcted rats. Methods: Wistar rats, N = 8-15 in each group, were divided as INF group and sham (SH) group and subdivided. The infarction was performed through ligation of the left anterior descending coronary artery. GC was estimated with pressure-volume curves. Vagotomy was performed by sectioning the dorsal and ventral branches. To verify the action of GABAB receptors, baclofen was injected via icv (intracerebroventricular). Intravenous prazosin was used to produce chemical sympathectomy. The lesion in the PVN of the hypothalamus was performed using a 1mA/10s electrical current and GE was determined by measuring the percentage of gastric retention (% GR) of a saline meal. Results: No significant differences were observed regarding GC between groups; vagotomy significantly reduced % GR in INF group; icv treatment with baclofen significantly reduced %GR. GABAB receptors were not conclusively involved in delaying GE; intravenous treatment with prazosin significantly reduced GR% in INF group. PVN lesion abolished the effect of myocardial infarction on GE. Conclusion: Gastric emptying of liquids induced through acute myocardial infarction in rats showed the involvement of the vagus nerve, alpha1- adrenergic receptors and PVN.

Cytochemical characterization of gill and hepatopancreatic cells of the crab Ucides cordatus (Crustacea, Brachyura) validated by cell metal transport

Ucides cordatus (Linnaeus, 1763) is a hypo-hyper-regulating mangrove crab possessing gills for respiratory and osmoregulatory processes, separated in anterior and posterior sections. They also have hepatopancreas, which is responsible for digestion and absorption of nutrients and detoxification of toxic metals. Each of these organs has specific cells that are important for in vitro studies in cell biology, ion and toxic metals transport. In order to study and characterize cells from gills and hepatopancreas, both were separated using a Sucrose Gradient (SG) from 10 to 40% and cells in each gradient were characterized using the vital mitochondrial dye DASPEI (2-(4-dimethylaminostyryl)-N- ethylpyridinium iodide) and Trichrome Mallory's stain. Both in 20 and 40% SG for gill cells and 30% SG for hepatopancreatic cells, a greater number of cells were colored with DASPEI, indicating a larger number of mitochondria in these cells. It is concluded that the gill cells present in 20% and 40% SG are Thin cells, responsible for respiratory processes and Ionocytes responsible for ion transport, respectively. For hepatopancreatic cells, the 30% SG is composed of Fibrillar cells that possess larger number of membrane ion and nutrient transporters. Moreover, the transport of toxic metal cadmium (Cd) by isolated hepatopancreatic cells was performed as a way of following cell physiological integrity after cell separation and to study differences in transport among the cells. All hepatopancreatic cells were able to transport Cd. These findings are the first step for further work on isolated cells of these important exchange epithelia of crabs, using a simple separation method and to further develop successful in vitro cell culture in crabs.