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1.
Arch Microbiol ; 203(4): 1439-1450, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33392625

RESUMO

Chlamydomonas reinhardtii is one of the most characterized green algae. The open-pond cultivation can be challenging due to sensitivity of strain to fluctuating environmental conditions and unavailability of low-cost photoautotrophic media. In this study, the photoautotrophic growth of C. reinhardtii was evaluated in 1-m2 open ponds placed in greenhouse. Sodium bicarbonate (NaHCO3) was evaluated as an alternative buffering agent to tris. The effect of buffer and pH was tested. The growth was studied in the presence of various nitrogen [urea and ammonium bicarbonate (NH4HCO3)] sources. In the study, it was found that 125-ppm NaHCO3 as an optimum concentration. The buffering agent in the media was found to have major impact on growth. Without buffering agent, culture did not grow, and pH drop was observed. The sodium bicarbonate-buffered media reported to have the lowest bacterial contamination (18.3%), highest AFDW per OD (0.39 ± 0.027 g/L) and higher Fv/Fm (0.714 ± 0.016), whereas these values were found to be 62%, 0.19 ± 0.02 g/L and 0.537 ± 0.053 for tris-grown culture, respectively. The pH 7.0-7.5 was determined as an optimum, whereas pH 6.5-7.0 and 8.0-8.5 were found to affect the growth and induce palmelloidy. The OD and AFDW of culture grown in NH4HCO3 were found equivalent to a standard nitrogen source (NH4Cl), whereas culture shown poor growth in urea. Based on these data, NH4HCO3 media recipe and the optimized cultivation parameters were selected for photoautotrophic cultivation of Chlamydomonas in greenhouse open ponds.


Assuntos
Processos Autotróficos , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Processos Fototróficos , Lagoas/química , Chlamydomonas reinhardtii/metabolismo , Meios de Cultura/química , Concentração de Íons de Hidrogênio , Nitrogênio/análise , Bicarbonato de Sódio/análise
2.
Artif Organs ; 45(7): 779-783, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33534933

RESUMO

We propose a new 45X, four-stream, triple-concentrate, bicarbonate-based dialysis fluid delivery system, allowing a wide range of dialysis fluid sodium concentrations\\ (DFNa ) without affecting the concentrations of other crucial solutes. The four streams consist of product water (W), and concentrates with sodium chloride (S), acid (A), and sodium bicarbonate (B). An adjustment in the DFNa in this new system requires changes only in the W and S concentrate streams. The ingredients in A and B concentrates do not change.


Assuntos
Soluções para Diálise/química , Bicarbonato de Sódio/análise , Cloreto de Sódio/análise , Humanos , Diálise Renal
3.
Artif Organs ; 45(12): 1576-1581, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34637152

RESUMO

BACKGROUND: Hemodialysis corrects metabolic acidosis by transferring bicarbonate or bicarbonate equivalents across the dialysis membrane from the dialysis fluid to the plasma. With the conventional three-stream bicarbonate-based dialysis fluid delivery system, a change in the bicarbonate concentration results in changes in the other electrolytes. In practice, the dialysis machine draws either a little less or more from the bicarbonate concentrate and a little more or less from the acid concentrate, respectively in a three-stream delivery system. The result not only changes the bicarbonate concentration of the final dialysis fluid but also causes a minor change in the other ingredients. METHODS: We propose a four-stream bicarbonate-based dialysis fluid delivery system consisting of an acid concentrate, a base concentrate, a product water, and a new sodium chloride concentrate. RESULTS: By adjusting the flow rate ratio between the sodium chloride and sodium bicarbonate concentrates, one can achieve the desired bicarbonate concentration in the dialysis fluid without changing the concentration of sodium or ingredients in the acid concentrate. The chloride concentration mirrors the change in bicarbonate but in the opposite direction. CONCLUSION: A four-stream, bicarbonate-based dialysis fluid delivery system allows the bicarbonate concentration to be changed without changing the other constituents of the final dialysis fluid.


Assuntos
Soluções para Diálise/química , Bicarbonato de Sódio/análise , Cloreto de Sódio/análise , Humanos , Diálise Renal/métodos
4.
Int J Biometeorol ; 62(5): 897-905, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29322254

RESUMO

The aim of this study was to investigate the effects of balneotherapy on chronic low back pain. This is a minimized, follow-up study evaluated according to the analysis of intention to treat. The subjects included in the study were 105 patients suffering from chronic low back pain. The control group (n = 53) received the traditional musculoskeletal pain killer treatment, while the target group (n = 52) attended thermal mineral water treatment for 3 weeks for 15 occasions on top of the usual musculoskeletal pain killer treatment. The following parameters were measured before, right after, and 9 weeks after the 3-week therapy: the level of low back pain in rest and the level during activity are tested using the Visual Analog Scale (VAS); specific questionnaire on the back pain (Oswestry); and a questionnaire on quality of life (EuroQual-5D). All of the investigated parameters improved significantly (p < 0.001) in the target group by the end of the treatment compared to the base period, and this improvement was persistent during the follow-up period. There were no significant changes in the measured parameters in the control group. Based on our results, balneotherapy might have favorable impact on the clinical parameters and quality of life of patients suffering from chronic low back pain.


Assuntos
Balneologia , Bicarbonatos/uso terapêutico , Dor Lombar/terapia , Magnésio/uso terapêutico , Águas Minerais/uso terapêutico , Bicarbonato de Sódio/uso terapêutico , Idoso , Bicarbonatos/análise , Doença Crônica , Feminino , Humanos , Magnésio/análise , Masculino , Pessoa de Meia-Idade , Águas Minerais/análise , Medição da Dor , Qualidade de Vida , Método Simples-Cego , Bicarbonato de Sódio/análise
5.
Food Microbiol ; 50: 102-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25998822

RESUMO

In the present study, we evaluated the antimicrobial activity of neutral electrolyzed water (NEW) against 14 strains of spoilage Pseudomonas of fresh cut vegetables under cold storage. The NEW, produced from solutions of potassium and sodium chloride, and sodium bicarbonate developed up to 4000 mg/L of free chlorine, depending on the salt and relative concentration used. The antimicrobial effect of the NEW was evaluated against different bacterial strains at 10(5) cells/ml, with different combinations of free chlorine concentration/contact time; all concentrations above 100 mg/L, regardless of the salt used, were found to be bactericidal already after 2 min. When catalogna chicory and lettuce leaves were dipped for 5 min in diluted NEW, microbial loads of mesophilic bacteria and Enterobacteriaceae were reduced on average of 1.7 log cfu/g. In addition, when lettuce leaves were dipped in a cellular suspension of the spoiler Pseudomonas chicorii I3C strain, diluted NEW was able to reduce Pseudomonas population of about 1.0 log cfu/g. Thanks to its high antimicrobial activity against spoilage microorganisms, and low cost of operation, the application of cycles of electrolysis to the washing water looks as an effective tool in controlling fresh cut vegetable microbial spoilage contamination occurring during washing steps.


Assuntos
Cloro/análise , Enterobacteriaceae/fisiologia , Contaminação de Alimentos/prevenção & controle , Pseudomonas/fisiologia , Verduras/microbiologia , Água/química , Carga Bacteriana , Cichorium intybus/microbiologia , Contagem de Colônia Microbiana , Desinfetantes/análise , Eletrólise/economia , Eletrólise/métodos , Enterobacteriaceae/efeitos dos fármacos , Microbiologia de Alimentos/métodos , Lactuca/microbiologia , Cloreto de Potássio/análise , Bicarbonato de Sódio/análise , Cloreto de Sódio/análise
6.
Nature ; 448(7157): 1054-7, 2007 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-17728758

RESUMO

There are five known taste modalities in humans: sweet, bitter, sour, salty and umami (the taste of monosodium glutamate). Although the fruitfly Drosophila melanogaster tastes sugars, salts and noxious chemicals, the nature and number of taste modalities in this organism is not clear. Previous studies have identified one taste cell population marked by the gustatory receptor gene Gr5a that detects sugars, and a second population marked by Gr66a that detects bitter compounds. Here we identify a novel taste modality in this insect: the taste of carbonated water. We use a combination of anatomical, calcium imaging and behavioural approaches to identify a population of taste neurons that detects CO2 and mediates taste acceptance behaviour. The taste of carbonation may allow Drosophila to detect and obtain nutrients from growing microorganisms. Whereas CO2 detection by the olfactory system mediates avoidance, CO2 detection by the gustatory system mediates acceptance behaviour, demonstrating that the context of CO2 determines appropriate behaviour. This work opens up the possibility that the taste of carbonation may also exist in other organisms.


Assuntos
Dióxido de Carbono/análise , Drosophila melanogaster/fisiologia , Paladar/fisiologia , Animais , Comportamento Animal , Encéfalo/citologia , Encéfalo/metabolismo , Dióxido de Carbono/química , Gelo-Seco , Preferências Alimentares , Gases/química , Concentração de Íons de Hidrogênio , Ligantes , Neurônios/metabolismo , Olfato/fisiologia , Bicarbonato de Sódio/análise , Soluções/química , Água/química
7.
Commun Agric Appl Biol Sci ; 78(2): 139-49, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25145234

RESUMO

Green and blue molds, respectively caused by Penicillium digitatum Sacc., and P. italicum Wehmer, are the most important postharvest diseases of citrus fruit Postharvest management of these pathogens is mainly based on the application of thiabendazole (TBZ) or imazalil (IMZ) fungicides. However, their intensive and prolonged use has led to the selection of TBZ- IMZ-resistant strains of these pathogens and to a reduction of TBZ and IMZ effectiveness to control postharvest decay. However, while TBZ may become completely ineffective against TBZ-resistant strains of P. digitatum, reduction of IMZ efficacy is only partial, and an effective control of decay can still be achieved by increasing its concentration, heating the treatment-solution and/or combining IMZ with sodium bicarbonate (SBC) or other food additives or natural salts. In this study, 'Desiderio' and 'Nova' mandarins were inoculated with spores of a sensitive strain of P. digitatum to IMZ and TBZ (PDs) or with a strain of P. digitatum with double resistance to both fungicides (PDr) and immersed in IMZ or TBZ emulsions at increasing concentrations up to 1000 mg/L or in IMZ (25, 200 or 400 mg/L), SBC (0.5, 1 or 2%) or IMZ + SBC emulsions either at 20 or 40 degrees C. IMZ was superior to TBZ to control decay of 'Desiderio' mandarins incited by PDs and was also effective to control decay in fruit inoculated with PDr, while TBZ even at the highest rate was completely ineffective. In 'Desiderio' mandarins inoculated with PDs, a complete control of decay was achieved with 25 mg/L IMZ but in fruit inoculated with PDr, 25 mg/L IMZ were ineffective to control decay despite in combination with SBC at 2% a synergistic effect was detected. In contrast, a good control of decay was achieved with 400 mg/L IMZ. In 'Nova' mandarins after 1 week of incubation at 20 degrees C decay incidence in fruit dipped in 400 mg/L at 20 degrees C or 200 mg/L IMZ at 40 degrees C was almost completely inhibited, while the addition of SBC at 0.5, 1 or 2% did not improve treatments performance in fruit inoculated with PDs. However, when 'Nova' mandarins were inoculated with PDr, SBC showed a modest but significant control of decay and in combination with IMZ either at 400 mg/L and 20 degrees C or 200 mg/L and 40 degrees C, significantly improved decay control. SBC did not affect IMZ residue load in 'Valencia' oranges, whereas dipping the fruit in 400 mg/L IMZ at 20 degrees C produced similar IMZ residue load as dips at 200 mg/L IMZ at 40 degrees C. In all cases, residue levels of IMZ never exceeded 2 mg/kg, which is about 40% of the maximum residue limits (MRLs) allowed in European countries. Thus, despite the selection of IMZ-resistant strains of P. digitatum, IMZ continues to be highly effective to control green mold of citrus fruit at concentrations leaving on fruit surface residue levels below the MRLs.


Assuntos
Resíduos de Drogas/análise , Conservação de Alimentos/métodos , Fungicidas Industriais/análise , Fungicidas Industriais/farmacologia , Imidazóis/farmacologia , Penicillium/efeitos dos fármacos , Bicarbonato de Sódio/análise , Bicarbonato de Sódio/farmacologia , Citrus/química , Citrus/microbiologia , Farmacorresistência Fúngica , Frutas/química , Frutas/microbiologia , Temperatura Alta , Imidazóis/análise , Penicillium/crescimento & desenvolvimento
8.
Science ; 379(6638): eade8416, 2023 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-36952416

RESUMO

The use of alkaline salt lands for crop production is hindered by a scarcity of knowledge and breeding efforts for plant alkaline tolerance. Through genome association analysis of sorghum, a naturally high-alkaline-tolerant crop, we detected a major locus, Alkaline Tolerance 1 (AT1), specifically related to alkaline-salinity sensitivity. An at1 allele with a carboxyl-terminal truncation increased sensitivity, whereas knockout of AT1 increased tolerance to alkalinity in sorghum, millet, rice, and maize. AT1 encodes an atypical G protein γ subunit that affects the phosphorylation of aquaporins to modulate the distribution of hydrogen peroxide (H2O2). These processes appear to protect plants against oxidative stress by alkali. Designing knockouts of AT1 homologs or selecting its natural nonfunctional alleles could improve crop productivity in sodic lands.


Assuntos
Álcalis , Produtos Agrícolas , Subunidades gama da Proteína de Ligação ao GTP , Proteínas de Plantas , Tolerância ao Sal , Sorghum , Produtos Agrícolas/genética , Produtos Agrícolas/fisiologia , Peróxido de Hidrogênio/metabolismo , Oryza/genética , Oryza/fisiologia , Estresse Oxidativo/genética , Melhoramento Vegetal , Salinidade , Álcalis/análise , Álcalis/toxicidade , Bicarbonato de Sódio/análise , Bicarbonato de Sódio/toxicidade , Carbonatos/análise , Carbonatos/toxicidade , Tolerância ao Sal/genética , Sorghum/genética , Sorghum/fisiologia , Subunidades gama da Proteína de Ligação ao GTP/genética , Subunidades gama da Proteína de Ligação ao GTP/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Aquaporinas/metabolismo , Produção Agrícola , Loci Gênicos , Solo/química
9.
Environ Geochem Health ; 32(3): 243-57, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19894127

RESUMO

Several coastal plains of the Elba Island (Marina di Campo, Portoferraio, Schiopparello, Mola, Porto Azzurro and Barbarossa plains) in Tuscany (Italy) were studied to determine the causes of decline in groundwater quality, using major ion chemistry to establish the causes of groundwater salinization. The study demonstrates that salinization of coastal plain alluvial aquifers is not simply linked to seawater intrusion but is also intimately related to inflows from adjacent aquifers. Ionic ratios, correlation graphs and distribution value maps were employed as the means to understand the hydrochemistry of the study areas. The Mg/Cl ratio in particular can be considered a good tracer to distinguish the main salinization processes that control groundwater chemistry. Seawater intrusion only partly determines the chemistry of some groundwaters, which generally belong to a chloride facies where the salinity is derived principally from freshwater-seawater mixing and the participation of cation exchange. Proceeding inland groundwater quality seems to be principally determined by the inflow of Mg, Ca-HCO(3) or Ca, Na-HCO(3) waters formed from the weathering of silicate minerals in adjoining aquifers. Hydrolysis of these minerals is of prime importance in controlling groundwater chemistry in adjacent alluvial plains. The lateral recharge flows introduce water with a different chemical composition and this variable of freshwater recharge changes the hydrochemistry as a result of mixing between two or more waters types. This situation is further complicated when seawater and base exchange reactions participate, due to seawater intrusion.


Assuntos
Monitoramento Ambiental , Água Doce/química , Geografia , Água do Mar/química , Cloreto de Sódio/análise , Poluentes Químicos da Água/análise , Cálcio/análise , Carbonato de Cálcio/análise , Cidades , Condutividade Elétrica , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Íons/análise , Íons/química , Itália , Magnésio/análise , Bicarbonato de Sódio/análise , Cloreto de Sódio/química , Movimentos da Água
10.
Chemosphere ; 236: 124358, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31330435

RESUMO

In the present study, the mineralization performance and pathway of uric acid (UA) on boron-doped diamond (BDD) anodes were investigated. The oxidation behavior of UA on BDD surface was firstly tested through cyclic voltammetry measurements. The individual and joint effects of four quantitative parameters (applied current density, NaHCO3 concentration, NaCl concentration and flow rate) on UA mineralization were then examined with Doehlert experimental design. The results acquired by statistical analysis revealed that NaCl concentration and applied current density displayed the most dominant roles on UA degradation, while the influences of NaHCO3 concentration and flow rate were statistically insignificant. As a result, the following optimal conditions were reached: applied current density of 7.80 mA cm-2, NaHCO3 concentration of 6.0 mM, NaCl concentration of 9.0 mM and flow rate of 600 mL min-1, which gave a TOC decay of 89.4%, a specific energy consumption of 125.36 KWh kg-1 TOC, a combustion current efficiency of 15.0% and an electrical energy per order of 35.79 KWh m-3 order-1 within 30 min of electrolysis. Further results from LC/MS analysis confirmed the ring rupture of UA during the electrolysis, due to the attack of hydroxyl radicals and active chlorine species. Accordingly, two plausible degradation pathways of UA in bicarbonate and chloride media on BDD anode were proposed respectively.


Assuntos
Boro/química , Técnicas Eletroquímicas/métodos , Ácido Úrico/química , Poluentes Químicos da Água/química , Diamante , Eletricidade , Eletrodos , Eletrólise , Análise Fatorial , Radical Hidroxila , Oxirredução , Bicarbonato de Sódio/análise , Cloreto de Sódio/análise
11.
Med Oral Patol Oral Cir Bucal ; 13(7): E456-9, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18587311

RESUMO

OBJECTIVE: To determine the correlation between pH and bicarbonate of soda in blood and saliva in child and adolescent patients during the administration of 3 g/m2 of methotrexate. METHOD: A controlled clinical test was performed on 23 patients diagnosed with Acute Lymphoblastic Leukemia. Ages ranged from 4 to 18. The Spearman Correlation Coefficient was used to interpret the data. RESULTS: No significant correlation was found between pH levels and seric and salivary sodium bicarbonate. However, there was a significant correlation between the levels of sodium bicarbonate in the body fluids evaluated (rs 0.2576, p=0.0354). CONCLUSIONS: Changes modifying the microenvironment of the oral cavity probably do not allow saliva to be used to determine blood pH and seric bicarbonate.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Saliva/química , Bicarbonato de Sódio/análise , Adolescente , Criança , Pré-Escolar , Humanos , Concentração de Íons de Hidrogênio , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Bicarbonato de Sódio/sangue
12.
PLoS One ; 13(8): e0202205, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30125301

RESUMO

The aim of this study is to evaluate the definition of water chemical type, with particular attention to soda brine characteristics by assessing ionic composition and pH values on a large geographic scale and broad salinity (TDS) range of Eurasian inland saline surface waters, in order to rectify the considerable confusion about the exact chemical classification of soda lakes and pans. Data on pH and on the concentration of eight major ions were compiled into a database drawn from Austria, China, Hungary, Kazakhstan, Mongolia, Russia, Serbia, and Turkey. The classification was primarily based on dominant ions exceeding an equivalent percentage of 25 (> 25e%) of the total cations or anions, and the e% rank of dominant ions was also identified. We identified four major types: waters dominated by (1) Na-HCO3 (10.0%), (2) Na-HCO3 + CO3 (31.4%), (3) Na-Cl (45.9%), and (4) Na-SO4 (12.7%), considering only the first ion by e% rank. These major types can be divided into 30 subtypes in the dataset, taking into account the e% rank of all dominant ions. The major and subtypes of soda brine can be divided into "Soda" and "Soda-Saline" types. "Soda type" when Na+ and HCO3- + CO3(2-) are the first in the rank of dominant ions (> 25e%), and "Soda-Saline type" when Na+ is the first in the rank of dominant cations and the sum of HCO3- + CO3(2-) concentration exceeds 25e%, but it is not the first in the rank of dominant anions. Soda-saline type can be considered as a separate evolutionary stage between Soda and Saline types respect to the geochemical interpretation by saturation indexes of brines. The obtained overlapping ranges in distribution demonstrate that a pH measurement alone is not a reliable indicator to classify the permanent alkaline "soda type" and various other types of temporary alkaline waters.


Assuntos
Lagos/química , Ásia , Carbonatos/análise , Europa (Continente) , Concentração de Íons de Hidrogênio , Salinidade , Bicarbonato de Sódio/análise , Cloreto de Sódio/análise , Sulfatos/análise
13.
Anal Bioanal Chem ; 388(3): 683-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17404715

RESUMO

The mummification ritual in ancient Egypt involved the evisceration of the corpse and its desiccation using natron, a naturally occurring evaporitic mineral deposit from the Wadi Natrun, Egypt. The deposit typically contains sodium carbonate, sodium bicarbonate and impurities of chloride and sulfate as its major elemental components. It is believed that the function of the natron was to rapidly remove the water from the cadaver to prevent microbial attack associated with subsequent biological tissue degradation and putrefaction. Several specimens of natron that were recently collected from the Wadi Natrun contained coloured zones interspersed with the mineral matrix that are superficially reminiscent of extremophilic cyanobacterial colonisation found elsewhere in hot and cold deserts. Raman spectroscopy of these specimens using visible and near-infrared laser excitation has revealed not only the mineral composition of the natron, but also evidence for the presence of cyanobacterial colonies in several coloured zones observed in the mineral matrix. Key Raman biosignatures of carotenoids, scytonemin and chlorophyll have been identified.


Assuntos
Embalsamamento , Sedimentos Geológicos/análise , Múmias , Bicarbonatos/análise , Carbonatos/análise , Cianobactérias/isolamento & purificação , Egito , Embalsamamento/métodos , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Bicarbonato de Sódio/análise , Análise Espectral Raman , Sulfatos/análise
14.
Isotopes Environ Health Stud ; 43(1): 23-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17454270

RESUMO

Arterial partial pressure of carbon dioxide (paCO(2)) is commonly evaluated by an invasive test, the arterial blood gas analysis (ABG). The sodium [(13)C]bicarbonate breath test (SBT) can potentially estimate arterial paCO(2). We studied 55 subjects with respiratory disorders and performed the ABG and the SBT to determine if the SBT can predict hypercapnia. The percentage of (13)CO(2) recovered in exhaled breath at 30 minutes (PDR(30)) alone was able to discriminate clinically significant hypercapnia (>53 mmHg) with a sensitivity of 82 % and specificity of 93 % (p<0.001). To evaluate the clinical utility of the SBT as a non-invasive substitute to repeated ABG, we monitored the progress of seven chronic obstructive pulmonary disease (COPD) patients on therapy with both the ABG and the SBT. The PDR(30) values from the SBT were able to correctly predict improvement or worsening of paCO(2) with 100 % accuracy. In conclusion, the SBT is a simple test that can be used in clinical practice to detect clinically significant hypercapnia and monitor COPD patients before and after therapy.


Assuntos
Testes Respiratórios/métodos , Hipercapnia/diagnóstico , Bicarbonato de Sódio/análise , Idoso , Pressão Sanguínea , Dióxido de Carbono/sangue , Isótopos de Carbono , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão Parcial , Sensibilidade e Especificidade
15.
Med Oral Patol Oral Cir Bucal ; 12(6): E435-9, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17909509

RESUMO

OBJECTIVE: To analyze the behavior of pH and sodium bicarbonate (NAHCO3) in the saliva of patients with leukemia during the administration protocol for Methotrexate (Mtx). MATERIALS AND METHODS: A controlled clinical essay was carried out on 23 patients between 4 and 18 years of age with high-risk Acute Lymphoblastic Leukemia. Sampling was carried out at To: basal condition; T1: 12 hours after intravenous administration of sodium bicarbonate, before administering Mtx and T2: 3 hours after administering Mtx, the time of maximum concentration. Chiron-Diagnostic 378 equipment was used to determine pH and sodium bicarbonate. The data was interpreted using Analysis of Variance at the 5% significance level. RESULTS: The highest values of sodium bicarbonate were observed at T2, with salivary pH levels remaining within neutrality ranges, diminishing slightly in T1. CONCLUSION. In this study, the dose of sodium bicarbonate considered in the administration protocol of 3 g /m2 Mtx, kept sodium bicarbonate levels in saliva at normal levels and pH neutral.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Metotrexato/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Saliva/química , Saliva/metabolismo , Bicarbonato de Sódio/análise , Adolescente , Criança , Pré-Escolar , Protocolos Clínicos , Humanos , Concentração de Íons de Hidrogênio
16.
Int. j. high dilution res ; 21(2): 2-3, May 6, 2022.
Artigo em Inglês | LILACS, HomeoIndex (homeopatia) | ID: biblio-1396754

RESUMO

Homeopathy is controversial because using highly dilute medicines (high homeopathic potencies, HHP) beyond the Avogadro/Loschmidt limit. Previous publications [1,2] using NMR relaxation revealed the involvement of nanobubbles and/or nanoparticles and/or nanometric superstructures in high potentizations. Nano Tracking Analyse (NTA) demonstrated the presence of particles in HHPs [3,4]. WithSEM-EDX [5] we observed an ionic diversity common to all preparations including HHPs and significant differences in the relative quantity of each ion between different homeopathic manufacturing lines and controls. FTIR spectroscopy [6] shows that the molecular composition is that of carbonates, primarily sodium bicarbonate.Methods:To observe the materiality of homeopathic medicines a multidisciplinary approach is necessary. In collaboration with several universities,we canobserve these medications with NMR, NTA, SEM-EDX, FTIR, pH,and EPA. Results:The essential component of all already studied homeopathic medicines is sodium hydrogen carbonate modulated by some other elements in a specific quantity, size,and shape. The probability that the observed results could have occurred just by random chance can be rejected(significantlyabove the Avogadro limit) p < 0,001.Conclusions:The homeopathic medicines do contain material with a specific ionic composition even in HHPs diluted beyond the Avogadro/Loschmidt limit. This specificity can be attributed to the manufacturing process. These results demonstrate that the step-by-step process (dynamized or not) does not match the theoretical expectations in a dilution process. The starting material and dilution/dynamization method influencethe nature of these NPs. The role of carbonates and sodium bicarbonate must be carefully studied in the future. Its aqueous solution is alkaline in nature but itis an amphoteric compound, which means that the compound has both acidic as well as alkaline character. The reaction with acids results in sodium salts and carbonic acid and the reaction with the basic solution producescarbonates and water. Specific electric fields are indeed detectable.


Assuntos
Materia Medica , Dinamização , Nanopartículas , Microscopia Eletrônica de Varredura , Bicarbonato de Sódio/análise
17.
Talanta ; 150: 622-8, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26838451

RESUMO

This article demonstrates an example of a wearable chemical sensor based on a fingernail platform. Fingernails represent an attractive wearable platform, merging beauty products with chemical sensing, to enable monitoring of our surrounding environment. The new colorimetric pH fingernail sensor relies on coating artificial nails with a recognition layer consisted of pH indicators entrapped in a polyvinyl chloride (PVC) matrix. Such color changing fingernails offer fast and reversible response to pH changes, repeated use, and intense color change detected easily with naked eye. The PVC matrix prevents leaching out of the indicator molecules from the fingernail sensor toward such repeated use. The limited narrow working pH range of a single pH indicator has been addressed by multiplexing three different pH indicators: bromothymol blue (pH 6.0-7.6), bromocresol green (pH 3.8-5.4), and cresol red (pH 7.2-8.8), as demonstrated for analyses of real-life samples of acidic, neutral, and basic character. The new concept of an optical wearable chemical sensor on fingernail platforms can be expanded towards diverse analytes for various applications in connection to the judicious design of the recognition layer.


Assuntos
Técnicas Biossensoriais/métodos , Citrus/química , Água Potável/análise , Sucos de Frutas e Vegetais/análise , Unhas/química , Bicarbonato de Sódio/análise , Colorimetria , Humanos , Concentração de Íons de Hidrogênio
18.
J AOAC Int ; 88(4): 1118-25, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16152930

RESUMO

A method using liquid chromatography with tandem mass spectrometry was developed for the determination of 11 commonly used aminoglycoside antibiotics in meat. The proposed method is sufficiently sensitive (detection limits of 15 to 40 ppb for the various antibiotics) and highly selective. It is suitable for the quantitation and confirmation of aminoglycosides in a variety of matrixes (pork muscle, fish, and veal liver). Any multiresidue method for aminoglycosides must take into account their high affinity toward sample proteins and the significantly different pK values of the various analytes. The developed method uses a low-pH extraction with trichloracetic acid to ensure complete extraction of the analytes from the matrix. An anion-exchange step is used to remove the acid from the centrifuged extract. Aminoglycosides in this solution of low ionic strength can be quantitatively retained and afterwards eluted from a weak cation-exchanger solid-phase extraction (SPE) cartridge. The highly selective SPE steps produce clean extracts, which minimize possible suppression of the mass spectrometer signal.


Assuntos
Aminoglicosídeos/análise , Cromatografia Líquida/métodos , Fígado/metabolismo , Espectrometria de Massas/métodos , Ânions , Cátions , Cromatografia , Cromatografia por Troca Iônica , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Íons , Carne , Análise de Regressão , Reprodutibilidade dos Testes , Bicarbonato de Sódio/análise , Espectrometria de Massas por Ionização por Electrospray , Ácido Tricloroacético/análise , Água
19.
J Am Dent Assoc ; 136(7): 877-82, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16060468

RESUMO

BACKGROUND: Up-to-date studies are needed on the protection provided by face masks used by dentists. We assessed the relative filtering efficacy of two currently used surgical face masks (one a molded mask, the other a tie-on mask) and a certified personal particulate respirator, all made by a single manufacturer. METHODS: The authors sprayed bicarbonate particulate against a porcelain surface (representing the patient's mouth) and collected it via a mannequin head (representing the dentist's head) placed 40 centimeters away and a tube with two airflow rates (0.5 cubic meters per hour and 9 m3/hour). They calculated the dry residue weight. They performed three separate runs for each mask and three runs with no mask at the two airflow rates with and without aerosol. RESULTS: With no mask (control), the authors recorded significant weight gains at both airflow rates with and without vaporization. With vaporization, the three masks were associated with different dry residue weights (P < .03 with the Kruskal-Wallis test at both flow rates), the respirator propviding the lowest amount. The respirator provided an efficiency of 94 to 96 percent, compared with 90 to 92 percent and 85 to 86 percent for the molded and tie-on surgical masks, respectively. CONCLUSIONS: These data provide independent evidencependent evidence that a certified personalthat a certified personal respirator can be more effective than high quality surgical masks in dental settings. CLINICAL IMPLICATIONS: Dentists should be aware that a certified particulate respirator can provide them with superior filtering protection.


Assuntos
Poluentes Ocupacionais do Ar , Poluição do Ar em Ambientes Fechados , Consultórios Odontológicos , Inalação/fisiologia , Máscaras/normas , Aerossóis , Poluentes Ocupacionais do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Desenho de Equipamento , Filtração/instrumentação , Filtração/normas , Humanos , Manequins , Exposição Ocupacional , Dispositivos de Proteção Respiratória/normas , Bicarbonato de Sódio/análise , Ventilação , Volatilização
20.
Isotopes Environ Health Stud ; 41(4): 391-404, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16543194

RESUMO

The Lamas Basin is an area covering approximately 4,400 km(2) situated on the eastern Mediterranean coast of Turkey covered with highly karstified limestone and dolomitic limestone from the Miocene and Mesozoic age, respectively. Owing to the area's low karstification basement, groundwater in the karst aquifer circulates deep from the surface towards the springs along the coast as well as to the submarine springs. This study aims working out the salinization level and recharge characteristics of the Lamas Basin using environmental isotopes techniques. In the study, the data collected previously to discover, in general terms, the groundwater characteristics within the area are reanalyzed to fulfil the purpose of the study. In conclusion, it is found that the down gradient karst springs discharging along the Mediterranean coast mostly contain groundwater contributions from higher altitudes with depleted delta(18)O and delta(2)H compositions. The delta(18)O-altitude effect was determined as approximately-0.12 per thousand/100 m which may indicate sea-spray intrusion towards inland. As a result, the salinization level of coastal springs changes ranging between 1.2 % and 17.0 %. Owing to the seawater encroachment, Ca-HCO(3) water type changes to Na-HCO(3) or Na-Cl water by the cation exchange during the dry period. As the unique freshwater potential extends along the coastal area, the groundwater production should be exploited in a way that seawater encroachment is kept at minimum.


Assuntos
Água Doce/análise , Cloreto de Sódio/análise , Abastecimento de Água/análise , Bicarbonatos/análise , Deutério/análise , Fenômenos Geológicos , Geologia , Isótopos de Oxigênio/análise , Água do Mar , Bicarbonato de Sódio/análise , Trítio/análise , Turquia , Movimentos da Água
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