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1.
Carbohydr Polym ; 298: 120122, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36241294

RESUMO

Removal of the premetalized dyes from the effluents of textile and leather industries is still open. The work aims to investigate functional groups taking part in the sorption of premetalized dye Acid Blue 158:Cr on chitin/chitosan and to investigate the mechanism of the sorption. The process was spontaneous (negative value of the Gibbs function), endothermic (ΔH = 0.2679 kJ/mol) with an affinity between the AB 158:Cr and chitin (ΔS = 1.315 J/mol*K). Langmuir, Freundlich, and Dubinin-Radushkevich isotherms were used to approximate experimental data giving a good correlation. Maximal capacity was evaluated as 46.1 mg/g and 370.4 mg/g for chitin and chitosan, respectively. Kinetics was described with a pseudo-second-order model. It was shown that physical sorption and chemisorption can occur parallelly: chemisorption on amine groups via interaction with chromium and physical sorption on amine group or hydroxyl group via interaction with the azo core of the dye.


Assuntos
Quitosana , Poluentes Químicos da Água , Adsorção , Aminas , Quitina , Cromo , Corantes , Concentração de Íons de Hidrogênio , Cinética , Naftalenossulfonatos , Compostos Organometálicos , Termodinâmica
2.
Molecules ; 27(10)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35630833

RESUMO

The method of using high-performance liquid chromatography with a charged aerosol detector method (HPLC-CAD) was developed for the separation and determination of phospholipids isolated from cell membranes. The established cell lines-normal and neoplastic prostate cells and normal skin fibroblasts and melanoma cells-were selected for the study. Chromatographic separation was performed in the diol stationary phase using a gradient elution based on a mixture of n-hexane, isopropanol and water with the addition of triethylamine and acetic acid as buffer additives. Taking the elements of the Folch and Bligh-Dyer methods, an improved procedure for lipid isolation from biological material was devised. Ultrasound-assisted extraction included three extraction steps and changed the composition of the extraction solvent, which led to higher recovery of the tested phospholipids. This method was validated by assessing the analytical range, precision, intermediate precision and accuracy. The analytical range was adjusted to the expected concentrations in cell extracts of various origins (from 40 µg/mL for PS up to 10 mg/mL for PC). Both precision and intermediate precision were at a similar level and ranged from 3.5% to 9.0%. The recovery for all determined phospholipids was found to be between 95% and 110%. The robustness of the method in terms of the use of equivalent columns was also confirmed. Due to the curvilinear response of CAD, the quantification was based on an internal standard method combined with a power function transformation of the normalized peak areas, allowing the linearization of the signal with an R2 greater than 0.996. The developed method was applied for the isolation and determination of glycerophospholipids from cell membranes, showing that the profile of the tested substances was characteristic of various types of cells. This method can be used to assess changes in metabolism between normal cells and neoplastic cells or cells with certain pathologies or genetic changes.


Assuntos
Glicerofosfolipídeos , Fosfolipídeos , Aerossóis/análise , Cromatografia Líquida de Alta Pressão/métodos , Fosfolipídeos/análise , Solventes
3.
Cytokine ; 150: 155780, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34896730

RESUMO

OBJECTIVE: Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal non-malignant disease in which hematopoietic cell apoptosis may play an important pathophysiological role. Previous studies of the content of phosphatidylinositol (3,4,5)-trisphosphate (PI(3,4,5)P3) indicated the possibility of remote transmission of anti-apoptotic signals between pathological and normal hematopoietic progenitors. METHODS: The study determined the plasma levels of beta chemokines and cytokines in N = 19 patients with PNH and 31 healthy controls. The research material was peripheral blood plasma (EDTA) stored at -80 °C until the test. Beta chemokine and cytokine concentrations were tested in duplicate with Bio-Plex Pro Human Cytokine Assay (Bio-Rad, Hercules, CA, USA) using a Luminex 200 flow cytometer and xPONENT software (Luminex Corporation, Austin, TX, USA). In peripheral blood CD34+ cells we tested the proportions of PI(3,4,5)P3+ and Annexin binding apoptotic phenotype using FC and phosflow. RESULTS: Compared to the control group, the PNH group showed a significant increase in the plasma concentration of some beta chemokines and cytokines, including MIP-1alpha/CCL3, eotaxin/CCL11, MCP1/CCL2, IL4 and G-CSF. In the group of PNH patients, a significant decrease in the concentration of some cytokines was also observed: RANTES/CCL5, MIP-1beta/CCL4, PDGF-BB and IL9. At the same time, the plasma concentrations of the chemokine IP-10/CXCL10 and the cytokines IFN-gamma, TNF, IL6 and IL10 showed no significant deviations from the values for the control group. Anti-apoptotic phenotype and phosphatidylinositol (3,4,5)-trisphosphate content in PNH clone of CD34+ cells were associated with the level of CCL3 and negatively associated with CCL5, CCL4, PDGF-BB and IL9. CONCLUSIONS: This data suggest the existence of apoptotic and PI(3,4,5)P3 imbalance in PNH CD34+ cells driven by anti-apoptotic cytokine biosignature in PNH. Plasma cytokines and intracellular enzymes that regulate the phosphoinositide pathways may become a therapeutic target in PNH.


Assuntos
Hemoglobinúria Paroxística , Anti-Inflamatórios , Quimiocinas , Quimiocinas CC , Citocinas , Hemoglobinúria Paroxística/genética , Hemoglobinúria Paroxística/patologia , Humanos
4.
Carbohydr Polym ; 202: 397-403, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30287015

RESUMO

Chitin, poly N-acetylglucosamine, has a great potential for use on an industrial scale as an enzyme carrier but it has an unfavorable particle structure that can be modified using ionic liquids (ILs). Several ionic liquids were investigated that have the same substituents on the ring (methyl- and propyl-) but differed in the type of cationic ring (pyrrolidinium, piperidinium, and piperazinium). Organic acid ions (acetic and lactic) were used as counter ions. 1-ethyl-3-methyl-imidazolium acetate and 1-ethyl-3-methyl-imidazolium lactate were used as a reference. The results confirm that the chitin particle structure or size, or both, simultaneously changes if chitin is dissolved in an IL and then precipitated. Organic acid anions and short substituents on the cationic ring of ILs influenced particle modification substantially, whereas the type of ring played a minor role. Additionally, the ionic liquids [MPpyrr][OAc], [MPpip][OAc] and [DMPpz][OAc] could be reused up to at least 4 times without losing their ability to dissolve chitin.

5.
Adv Clin Exp Med ; 26(5): 751-760, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29068569

RESUMO

BACKGROUND: Oxidative stress accompanies neurodegeneration and also causes abnormalities in thiaminedependent processes. These processes have been reported to be diminished in the brains of patients with several neurodegenerative diseases. OBJECTIVES: The aim of this work was to conduct a comparative analysis of the impact of supplemented thiamine on the viability of human B lymphocytes with CAG abnormal expanded huntingtin gene (mHTT) (GM13509) and control, B lymphocytes without mHTT (GM14467) through the following studies: determination of the supplemented thiamine concentrations, which are effective for cell growth stimulation after incubation in thiamine deficit conditions; determination of cell capability to intake the exogenous thiamine; evaluation of exogenous thiamine influence on the profile of the genes related to thiamine and energy metabolism; determination of ATP synthesis and activities of thiamine-dependent enzymes, KGDHC and BCKDHC in the intact cells and upon the exogenous thiamine. MATERIAL AND METHODS: The following methods were used: EZ4U test for cell growth analysis; HPLC for determination of thiamine intake and ATP synthesis, qRT-PCR for evaluation of the gene profiles and spectrophotometric method for KGDHC and BCKDHC activities determination. RESULTS: Maximal cell growth stimulation was observed at 2.5 mM in GM14467 up to 135% of the control culture and at 5.0 mM in GM13509 cells up to 165% of the control culture. Native levels of total ATP and KGDHC and BCKDHC activities in both cell types were comparable and did not changed upon thiamine deficit or supplementation. GM13509 cells showed more of an increase in growth stimulation upon thiamine supplementation than GM14467 cells and this effect was reflected in the increase of intracellular thiamine concentration. CONCLUSIONS: The above results and reported changes in expression of GAPDH, IDH1 and SLC19A3 genes observed upon thiamine deficit conditions suggest that intracellular thiamine status and energy metabolism can have a role in HD pathogenesis.


Assuntos
Linfócitos B/efeitos dos fármacos , Doença de Huntington/tratamento farmacológico , Tiamina/farmacologia , 3-Metil-2-Oxobutanoato Desidrogenase (Lipoamida)/metabolismo , Trifosfato de Adenosina/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Estudos de Casos e Controles , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Metabolismo Energético/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica , Gliceraldeído-3-Fosfato Desidrogenases/genética , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Humanos , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Doença de Huntington/genética , Doença de Huntington/imunologia , Doença de Huntington/metabolismo , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Complexo Cetoglutarato Desidrogenase/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Tiamina/metabolismo , Fatores de Tempo
6.
J Biotechnol ; 251: 94-98, 2017 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-28435098

RESUMO

Chitin deacetylase is the only known enzyme that can deacetylate the N-acetyl-d-glucosamine units in chitin and chitosan to D-glucosamine. Unfortunately, this enzyme, originally obtained from fungi, usually has low activity. Here, we present that it is possible to enhance the activity of chitin deacetylase using the ionic liquid [Bmim][Br]. An increase in activity of up to 160% from the basal chitin deacetylase activity was observed. Kinetic investigations suggest that [Bmim][Br] is a non-essential activator.


Assuntos
Amidoidrolases/química , Imidazóis/química , Líquidos Iônicos/química , Quitosana/química , Cinética
7.
Acta Biochim Pol ; 62(2): 229-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25856560

RESUMO

Nano- and microemulsions containing as the oil phase caprylic/capric propylene glycol diesters (Crodamol PC) were investigated as potential vehicle for controlled release of geranic acid. The influence of emulsifiers and co-surfactants on stability of the emulsions was investigated. Different kind of polysorbates (ethoxylated esters of sorbitan and fatty acids) were applied as the emulsifiers. The short-chain alcohols (ethanol, 1-propanol, 1-butanol) were used as co-surfactants. The emulsions were prepared at ambient temperature (25°C), by the phase inversion composition method (PIC). The stable O/W high dispersed emulsion systems based on Crodamol PC, of mean droplets size less than 200 nm, were prepared. Microemulsions stabilized by the mixture of Polisorbat 80 and 1-butanol were characterized by the largest degree of dispersion (137 nm) and the lowest PDI value (0.094), at surfactant/co-surfactant: oil weight ratio 90:10. The stable nano-emulsion (mean droplet size of 33 nm) was obtained for surfactant: oil (S:O) weight ratio 90:10, without co-surfactant addition. This nano-emulsion was chosen to release studies. The obtained results showed that the prepared stable nano-emulsion can be used as a carrier for controlled release of geranic acid. The active substance release from the nano-emulsion and the oil solution, after 24 hours was 22%.


Assuntos
Preparações de Ação Retardada/química , Emulsões/química , Propilenoglicol/química , Terpenos/química , 1-Butanol/química , Caprilatos/química , Ácidos Decanoicos/química , Ésteres/química , Nanoestruturas/química , Polietilenoglicóis/química , Polissorbatos/química , Tensoativos/química , Terpenos/farmacocinética
8.
Med Princ Pract ; 24(1): 84-91, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25359228

RESUMO

OBJECTIVE: With a microcomputed tomography (microCT) imaging device, we aimed to quantitatively evaluate root canal fillings after commonly used endodontic procedures and also tested the suitability of microCT for this purpose. MATERIALS AND METHODS: Eighty single roots were instrumented and obturated with gutta-percha and Tubli-Seal. They were divided into 4 groups of 20. The Hand groups were instrumented with hand files and filled with thermoplastic (Th) compaction and cold lateral (CL) condensation, i.e. Hand-Th and Hand-CL, respectively. The Rot groups, i.e. Rot-Th and Rot-CL, were instrumented with a rotary ProFile system and filled as above. The roots were scanned and 3-dimensional (3D) visualization was obtained. The number, size, percentage of volume and distribution of voids at the filling/dentine interface (i-voids) and voids surrounded by filling material (s-voids) were measured. RESULTS: Canal fillings differed significantly with regard to the size of both types of voids and the average number of i-voids. All canals presented a low volume of voids. The highest percentage (0.69%) was found for i-voids in the Hand-CL group, while the lowest volume (0.11% for s-voids and 0.14% for i-voids) was in the Hand-Th canals. Apically, in the last 3 mm, i-voids were observed mainly in the Th groups, and s-voids occurred mostly in the coronal part of the canal filling in all cases. CONCLUSION: MicroCT was a useful tool for 3D quantitative evaluations of these root canal fillings. None of the root canal instrumentation and filling methods ensured void-free obturation. CL condensation produced mainly i-voids. With Th compaction, internal s-voids were particularly common, but there were mainly i-voids in the apical part.


Assuntos
Guta-Percha , Materiais Restauradores do Canal Radicular/normas , Obturação do Canal Radicular/normas , Cimento de Óxido de Zinco e Eugenol , Análise de Variância , Humanos , Obturação do Canal Radicular/métodos , Microtomografia por Raio-X/métodos
9.
Acta Biochim Pol ; 61(4): 615-31, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25473654

RESUMO

Regimen-related mucosal toxicity is extremely common following cytotoxic chemotherapy and radiotherapy. Mucositis is as an important determinant of the inflammatory response and infectious complications in cancer treated patients. Most assessment scales for mucosal damage are focussed on oral mucositis, since it is easy to evaluate. Measuring gastrointestinal musocal damage objectively remains difficult because it cannot be seen directly or readily detected. One of potential non-invasive biomarkers of gastrointestinal mucosal damage is plasma citrulline level. Citrulline is an amino acid produced by small bowel enterocytes. Low concentration of free circulating citrulline signifies severe intestinal mucosal damage in humans with nonmalignant disorders, such as villous atrophy-associated diseases, short bowel syndrome, Crohn's disease, and is used in follow-up after small bowel transplantation. The plasma citrulline level is a reliable and objective biochemical marker of enterocyte mass and function in humans, and therefore can be used to monitor enterocyte toxicity resulting from chemotherapy and radiotherapy during anticancer therapy in patients with severely disturbed gut integrity.


Assuntos
Biomarcadores/sangue , Citrulina/sangue , Mucosa Intestinal/patologia , Intestino Delgado/citologia , Animais , Humanos , Mucosite/sangue
10.
Postepy Hig Med Dosw (Online) ; 68: 310-5, 2014 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-24864081

RESUMO

INTRODUCTION: The aim of the study was to apply microcomputed tomography to quantitative evaluation of voids and to test any specific location of voids in tooth's root canal obturations. MATERIALS AND METHODS: Twenty root canals were prepared and obturated with gutta-percha and Tubli-Seal sealer using the thermoplastic compaction method (System B+Obtura II). Roots were scanned and three-dimensional visualization was obtained. The volume and Feret's diameter of I-voids (at the filling/dentine interface) and S-voids (surrounded by filling material) were measured. RESULTS: The results revealed that none of the scanned root canal fillings were void-free. For I-voids, the volume fraction was significantly larger, but their number was lower (P=0.0007), than for S-voids. Both types of voids occurred in characteristic regions (P<0.001). I-voids occurred mainly in the apical third, while S-voids in the coronal third of the canal filling. CONCLUSIONS: Within the limitations of this study, our results indicate that microtomography, with proposed semi-automatic algorithm, is a useful tools for three-dimensional quantitative evaluation of dental root canal fillings. In canals filled with thermoplastic gutta-percha and Tubli-Seal, voids at the interface between the filling and canal dentine deserve special attention due to of their periapical location, which might promote apical microleakage. Further studies might help to elucidate the clinical relevance of these results.


Assuntos
Algoritmos , Infiltração Dentária/diagnóstico por imagem , Cavidade Pulpar/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Materiais Restauradores do Canal Radicular/análise , Obturação do Canal Radicular , Microtomografia por Raio-X/métodos , Guta-Percha/análise , Humanos , Imageamento Tridimensional , Cimento de Óxido de Zinco e Eugenol/análise
11.
Ann Agric Environ Med ; 20(4): 779-83, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24364452

RESUMO

Determination of the plasma amino acid (AA) levels in Huntington's disease (HD) can make it possible to find the metabolic markers used in early diagnosis. The aim of the presented study was to determine the AA profile in plasma samples from HD patients and presymptomatic carriers, compared to healthy subjects. The AA profile was analyzed with HPLC. The study concerned 59 participants: 30 subjects with abnormal CAG repeats expansion (>36) in the HTT gene, and 29 healthy subjects. Each participant was analyzed with regard to the parameters characterizing the metabolic state and protein metabolism, such as: urea, creatinine, glucose, total protein, TSH (thyroid-stimulating hormone), cortisol, ESR (erythrocyte sedimentation rate), and CRP (C-reactive protein). Simple statistical comparisons showed 5 AA to be significantly lower in the HD group, compared to the control group, i.e.: Asn, His, Leu, Ser, Thr. Creatinine and creatinine clirens were found to be lower in the HD group, compared to controls, while ESR was noticed to be higher. As a result of Canonical Discriminant Analysis, 5 of all AA assayed (Leu, Gln, Asn, Ser and Lys) were selected as variables that allow distinguishing between HD patients and healthy subjects with 75% of correctness. Concerning AA profile and biochemical markers, Canonical Discriminant Analysis detected a panel of variables (Ser, Asn, Gln, Orn, Pro, Arg, Met, Cit, Val, TSH, glucose, urea, creatinine clirens, total protein, cortisol, CRP) distinguishing HD from the control group, with 90% of correctness. Among all the parameters tested, Asn and Ser were revealed in all statistical analyses and could be considered as potential plasma HD biomarkers.


Assuntos
Aminoácidos/sangue , Heterozigoto , Doença de Huntington/metabolismo , Adulto , Aminoácidos/metabolismo , Feminino , Predisposição Genética para Doença , Humanos , Doença de Huntington/genética , Masculino , Pessoa de Meia-Idade , Mutação
12.
Acta Biochim Pol ; 60(4): 779-82, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24432331

RESUMO

The formation of oil/water (O/W) nano-emulsions suitable for cosmeceutical application was studied. Nano-emulsions were prepared by using phase inversion composition (PIC) method, one of the low-energy emulsification methods. The process consist of stepwise water addition to oil/surfactant mixture, at T = 25°C. Caprylic/capric triglycerides (GTCC), propylene glycol dicaprylate/dicaprate (PC) and oleic acid (OA) were applied as an oil phase. Polysorbate 80 was used as the surfactant. Kinetic stability of the nano-emulsions was analyzed by measuring droplet size as a function of time for different oil/surfactant ratio. The particles size distribution was analyzed by means DLS measurement technique (Dynamic Light Scattering), using Zetasizer Nano ZS (Malvern Instruments, UK). One of triterpenoic acid, practically non-water soluble substance was selected as an active and incorporated into the stable formulation. The obtained results proved that the nanoemulsion NE-T80-GTCC-20:80 based on caprylic/capric triglycerides with the oil/surfactant ratio O/S = 2 0:80 and the droplet size r = 25 nm was the most stable one and additionally showed the highest solubilisation capacity for the triterpene.


Assuntos
Química Farmacêutica , Cosméticos , Emulsões/química , Óleos/química , Nanoestruturas/química , Polietilenoglicóis/química , Tensoativos/química , Água/química
13.
Acta Pol Pharm ; 69(5): 799-808, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23061275

RESUMO

High-performance liquid chromatography (HPLC) is a technique most frequently used for the assessment of biologically active peptides. Owing to the ionic character of these compounds, they may also be separated and assayed using capillary electrophoresis (CE), which offers very high efficiency, short analysis time and low consumption of reagents, and is used increasingly more often. The paper describes the combination of HPLC and CE in order to increase the efficiency of the separation of complex mixture of peptides (active substance and its related impurities). The developed two-dimensional HPLC-CE technique was employed for the analysis of the impurities of octreotide, a cyclic octapeptide used in therapy. Because distinct separation mechanisms are used, the two-dimensional technique ensures higher separation efficiency and a more comprehensive impurity profile of the medicinal product than either of the techniques used separately.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Misturas Complexas/química , Eletroforese Capilar/métodos , Octreotida/análogos & derivados , Peptídeos/análise , Produtos Biológicos/análise , Produtos Biológicos/química , Octreotida/análise , Octreotida/química , Peptídeos/química
14.
BMC Cancer ; 12: 349, 2012 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-22876876

RESUMO

BACKGROUND: To evaluate the value of KRAS codon 13 mutations in patients with advanced colorectal cancer (advanced CRC) treated with oxaliplatin and fluoropyrimidines. METHODS: Tumor specimens from 201 patients with advanced CRC from a randomized, phase III trial comparing oxaliplatin/5-FU vs. oxaliplatin/capecitabine were retrospectively analyzed for KRAS mutations. Mutation data were correlated to response data (Overall response rate, ORR), progression-free survival (PFS) and overall survival (OS). RESULTS: 201 patients were analysed for KRAS mutation (61.2% males; mean age 64.2 ± 8.6 years). KRAS mutations were identified in 36.3% of tumors (28.8% in codon 12, 7.4% in codon 13). The ORR in codon 13 patients compared to codon 12 and wild type patients was significantly lower (p = 0.008). There was a tendency for a better overall survival in KRAS wild type patients compared to mutants (p = 0.085). PFS in all patients was not different in the three KRAS genetic groups (p = 0.72). However, we found a marked difference in PFS between patients with codon 12 and 13 mutant tumors treated with infusional 5-FU versus capecitabine based regimens. CONCLUSIONS: Our data suggest that the type of KRAS mutation may be of clinical relevance under oxaliplatin combination chemotherapies without the addition of monoclonal antibodies in particular when overall response rates are important. TRIAL REGISTRATION NUMBER: 2002-04-017.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Códon , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Mutação , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Proteínas Proto-Oncogênicas p21(ras) , Resultado do Tratamento
15.
Amino Acids ; 43(4): 1653-61, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22349763

RESUMO

A new approach for the separation of 6-aminoquinolyl-carbamyl (AQC)-derivatized amino acids has been proposed. The chromatography used ion-pairing mechanism to increase the method selectivity. Mobile phase was based on triethylamine buffer containing N,N-dimethyloctylamine as a modifier. A number of factors, buffer composition and pH, counterion concentration, temperature and acetonitrile gradient profile, were optimized to achieve final chromatographic conditions. With the presented analytical method, the separation and identification of 34 AQC-amino acids and amino compounds present in human plasma is possible. The results of validation proved the applicability of the method for quantification of 27 amino acids in biological samples. The ultrafiltration proposed as deproteinization procedure gave repeatable and reliable results for the amino acids under investigation. This method introduced in routine testing can be a suitable tool for amino acid profiling in plasma including all aspects of clinical application.


Assuntos
Aminoácidos/sangue , Aminoquinolinas/química , Carbamatos/química , Acetonitrilas , Aminoácidos/química , Soluções Tampão , Cromatografia Líquida de Alta Pressão , Etilaminas , Humanos , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Temperatura , Ultrafiltração
16.
Ann Agric Environ Med ; 18(1): 79-84, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21736272

RESUMO

Dentists at work are susceptible to the development of health disorders. Bad working habits, repetitive tasks and uncomfortable posture contribute to musculoskeletal disorders (MSDs), stress and loss of production. The paper deals with the assessment of health status among dentists in Poland regarding the symptoms of musculoskeletal pain. The survey was conducted among 220 dentists. The questionnaire was concerned with demographic details, work duration and acquired specialization, organization and methods of work in the surgery, and also disorders connected with the musculoskeletal system and physical prophylactic activity. It was found that over 92% of the surveyed dentists experienced MSDs, especially in the neck (47%) and lower back (35%). More than 29% of the dentists experienced trouble with fingers, 23% with hip, whereas 20% demonstrated problems in the midback, and also in the shoulders (20%). Pain in the wrists was reported by 18.3%, and pain in the knees, feet or elbows by 15-16% of respondents. Statistical dependence was shown between the years of practice and the period of time when disorders occurred. Moreover, significance relationships were found between MSDs and both standing work position and non-use of rest breaks. It was concluded that limited ergonomics in the work environment of dentists results in MSDs, and its prevalence is very high. The symptoms of MSDs increased with the number of years of practice.


Assuntos
Dor nas Costas/etiologia , Odontólogos , Doenças Musculoesqueléticas/etiologia , Doenças Profissionais/epidemiologia , Dor/etiologia , Dor nas Costas/epidemiologia , Ergonomia , Feminino , Humanos , Masculino , Doenças Musculoesqueléticas/epidemiologia , Dor/epidemiologia , Polônia/epidemiologia , Fatores de Risco
17.
Biotechnol J ; 6(2): 244-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21298809

RESUMO

Chitin deacetylase is the only known enzyme catalyzing the hydrolysis of the acetamino linkage in the N-acetylglucosamine units of chitin and chitosan. This reaction can play an important role in enzymatic production of chitosan from chitin, or in enzymatic modification of chitosan, which has applications in medicine, pharmacy or plant protection. It was previously shown that acetic acid, a product of the deacetylation process, may act as an inhibitor of chitin deacetylase. Here we show the mechanism of inhibition of chitin deacetylase isolated from Absidia orchidis vel coerulea by acetic acid released during the deacetylation process. The process follows competitive inhibition with respect to acetic acid with an inhibition constant of K(i) = 0.286 mmol/L. These results will help to find the optimal system to carry out the enzymatic deacetylation process for industrial applications.


Assuntos
Amidoidrolases/metabolismo , Ácido Acético/metabolismo , Quitosana/metabolismo
18.
Talanta ; 83(2): 513-20, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21111167

RESUMO

The paper proposes a new method for amino acid determination which can be applied for amino acid profiling in solutions for parenteral nutrition. The MEKC method based on a mixed micellar system was developed for the separation of 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) derivatized amino acids. Background electrolyte was based on tris-borate buffer with high alkaline pH. Sodium dodecyl sulfate micelles were modified using 1,2-hexanediol as a co-surfactant. The effect of the modifier on amino acid migration was studied with respect to hydrophobicity of the analytes. The modifier appeared to be suitable to improve the separation of AQC-tagged amino acids without an adverse effect on buffer ionic strength or EOF velocity. The method was successfully validated and applied for amino acid profiling in medicinal preparations for parenteral nutrition. The results obtained were compared with a reference chromatographic method (amino acid analyser).


Assuntos
Aminoácidos/química , Aminoquinolinas/química , Carbamatos/química , Técnicas de Química Analítica , Infusões Parenterais/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Glicóis/química , Hexanos , Concentração de Íons de Hidrogênio , Micelas , Dodecilsulfato de Sódio/química , Succinimidas/química , Fatores de Tempo
19.
J Pharm Biomed Anal ; 50(1): 90-5, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19428212

RESUMO

Sodium caprylate and N-acetyltryptophan are the most frequently used stabilizers that protect the albumin from aggregation or heat induced denaturation. In turn citrates - excipients remaining after fractionation process - can be treated as by-product favoring leaching aluminum out of glass containers whilst albumin solution is stored. With ionic nature these substances have all the markings of a subject for capillary electrophoresis analysis. Thus CE methods were proposed as new approach for quality control of human albumin solution in terms of determination of stabilizers and citrates residue. Human albumin solutions both 5% and 20% from various manufacturers were tested. Indirect detection mode was set to provide sufficient detectability of analytes lacking of chromophores. As being anions analytes were separated with reversed electroosmotic flow. As a result of method optimization two background electrolytes based on p-hydroxybenzoic acid and 2,6-pyridinedicarboxylic acid were selected for stabilizers and citrates separation, respectively. The optimized methods were successfully validated. For citrates that require quantification below 100microM the method demonstrated the precision less than 4% and the limit of detection at 4microM. In order to check the new methods accuracy and applicability the samples were additionally tested with selected reference methods. The proposed methods allow reliable quantification of stabilizers and citrates in human albumin solution that was confirmed by method validation as well as result comparison with reference methods. The CE methods are considered to be suitable for quality control yet simplifying and reducing cost of analysis.


Assuntos
Albuminas/química , Citratos/análise , Eletroforese Capilar/métodos , Espectrofotometria Ultravioleta/métodos , Cromatografia em Gel , Humanos
20.
Virchows Arch ; 449(5): 572-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17016719

RESUMO

Sclerosing (pseudovascular) rhabdomyosarcoma in adults has been described as a rare variant of rhabdomyosarcoma characterized by extensive hyaline fibrosis and pseudovascular growth patterns. We describe another case of this rhabdomyosarcoma subtype including ultrastructural and genetic findings-the lesion presented in a 62-year-old male patient in the left lower leg. The tumor was located within the deep soft tissue with maximum diameter of 11.8 cm and skin ulceration. Ultrastructural analysis revealed irregularly distributed disorganized filaments without clear evidence of Z-bands and a richly collagenized matrix. Using comparative genomic hybridization, a sharply delineated loss of chromosomal region 10q22, loss of chromosome Y, and a gain of chromosome 18 (trisomy) were detected. Reciprocal translocations t(1;13) and t(2;13)(q35;q14) which are characteristic of alveolar rhabdomyosarcoma could be excluded. These findings, while showing a relation to other rhabdomyosarcoma subtypes, represent a relatively circumscribed genetic defect pattern in sclerosing (pseudovascular) rhabdomyosarcoma that is somewhat different from patterns described in most other rhabdomyosarcoma subtypes. Six months after tumor resection, the patient presented with metastatic disease. Further studies should concentrate on the identification of genes especially on chromosomal region 10q22 to elucidate more aspects in the pathogenesis of this rhabdomyosarcoma subtype.


Assuntos
Aberrações Cromossômicas , Rabdomiossarcoma/patologia , Neoplasias de Tecidos Moles/patologia , Cromossomos Humanos Par 10 , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rabdomiossarcoma/química , Rabdomiossarcoma/genética , Rabdomiossarcoma/ultraestrutura , Esclerose , Neoplasias de Tecidos Moles/química , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/ultraestrutura
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