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1.
Folia Morphol (Warsz) ; 82(4): 943-947, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36573361

RESUMO

The ability to navigate the complex and often deceptive branching patterns of the internal iliac artery can be decisive in planning and performing surgeries within the lesser pelvis. The following case report presents a peculiar quadruple division of the internal iliac artery, accompanied by a venous anastomotic structure. Apart from the posterior and anterior trunks, the superior vesicle and iliolumbar arteries arose independently from the internal iliac artery. The division was surrounded by a venous oval, compressing certain branches and potentially complicating surgical access. Due to the uncommon course of the internal iliac artery and the presence of the anastomosis, a possible nerve root compression has been identified. Both clinical significance and classification method of the case are discussed. Knowledge of this anatomical variation is valuable for both diagnosis and surgery, especially within the specialties of urology, gynaecology and general surgery.


Assuntos
Artéria Ilíaca , Pelve , Humanos , Artéria Ilíaca/cirurgia , Veias , Anastomose Cirúrgica , Aorta Abdominal
2.
J Photochem Photobiol B ; 167: 290-298, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28113130

RESUMO

A density in algal suspension causes a significant change in the intensity and spectral composition of light reaching individual cells. Measurements of chlorophyll fluorescence allow us to observe any general changes in the bioenergetic status of photosynthesis. The aim of the study was to determine the effect of cultivation density on the PSII photochemical efficiency of three species of algae (Chlorella vulgaris, Botryococcus braunii and Chlorella emersonii), each with a different rate of growth - high, medium and low - respectively. The cell density of algae in suspension differentiated through the cultivation time (2, 4, and 8days) and the spectral composition of light. The results showed that the density of cultivation led to change in the photosynthetic apparatus of algae. The differences described between each day of cultivation (2, 4, and 8) in the kinetics of chlorophyll a fluorescence intensity in cells of the algal strains under study probably resulted from the different phases of growth of these cultures. In addition the results showed the beneficial effect of far red light on the photosynthetic apparatus and the growth of biomass in investigated algal strains.


Assuntos
Luz , Microalgas/efeitos da radiação , Fotossíntese , Biomassa , Clorofila/metabolismo , Clorofila A , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Espectrometria de Fluorescência
3.
Food Funct ; 5(10): 2536-41, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25131001

RESUMO

Raspberries, derived from different cultivar varieties, are a popular ingredient of everyday diet, and their biological activity is a point of interest for researchers. The ethanol-water extracts from four varieties of red (Rubus idaeus'Ljulin', 'Veten', 'Poranna Rosa') and black (Rubus occidentalis'Litacz') raspberries were evaluated in the range of their antimicrobial properties as well as phenolic content - sanguiin H-6, free ellagic acid and anthocyanins. The antimicrobial assay was performed with the use of fifteen strains of bacteria, both Gram-negative and Gram-positive. The antimicrobial activity of the extracts varied and depended on the analysed strain of bacteria and cultivar variety, with the exception of Helicobacter pylori, towards which the extracts displayed the same growth inhibiting activity. Two human pathogens Corynebacterium diphtheriae and Moraxella catarrhalis proved to be the most sensitive to raspberry extracts. Contrary to the extracts, sanguiin H-6 and ellagic acid were only active against eight and nine bacterial strains, respectively. The determined MIC and MBC values of both compounds were several times lower than the tested extracts. The highest sensitivity of Corynebacterium diphtheriae to extracts from both black and red raspberries may be due to its sensitivity to sanguiin H-6 and ellagic acid.


Assuntos
Anti-Infecciosos/farmacologia , Ácido Elágico/farmacologia , Frutas/química , Taninos Hidrolisáveis/farmacologia , Rubus/química , Antocianinas/análise , Antocianinas/farmacologia , Anti-Infecciosos/análise , Cromatografia Líquida de Alta Pressão , Corynebacterium diphtheriae/efeitos dos fármacos , Ácido Elágico/análise , Helicobacter pylori/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Taninos Hidrolisáveis/análise , Moraxella catarrhalis/efeitos dos fármacos , Extratos Vegetais/análise , Extratos Vegetais/farmacologia
4.
Euro Surveill ; 14(33)2009 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-19712639

RESUMO

Antibiotic resistance and nosocomial infections have recently been recognised as a growing threat in Latvian hospitals. We used a modified point prevalence study design to gain accurate information on the antibiotic prescription pattern and the prevalence of nosocomial infections in different hospital departments. A given department was observed on a given day in a given month (May) five years in a row. All antibiotic treatments, dose and route of administration were recorded, in addition to demographic data. The most commonly used antibiotic groups were first generation cephalosporins (35.6-38.9%), broad-spectrum penicillins (17.5-23.0%), fluoroquinolones (8.4-14.5%) and aminoglycosides (7.7-12.6%). Cefazolin was the most commonly used antibiotic. Antibiotics were predominantly used intravenously. The proportion of oral administration varied from 15.1% to 21.8%. A large proportion (13.3%) of the antibiotics was administered without clear reason. The crude prevalence rate of infection treated with antibiotics was 19.3%. The average prevalence of nosocomial infections was found to be 3.6%. These prevalence studies provided an opportunity to compare hospitals and outline variations and problem areas. They indicated the main problems in antibiotic prescription: large interhospital variations in the choice of an antibiotic for the most common infections, frequent antibiotic use without clear reason, and predominant intravenous administration.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia , Surtos de Doenças/prevenção & controle , Surtos de Doenças/estatística & dados numéricos , Revisão de Uso de Medicamentos , Prescrições/estatística & dados numéricos , Uso de Medicamentos/estatística & dados numéricos , Humanos , Letônia/epidemiologia , Prevalência
6.
Exp Clin Endocrinol Diabetes ; 117(2): 64-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19194833

RESUMO

BACKGROUND: The prevalence of goitre and urinary iodine excretion (UIE) indicate endemic iodine deficiency (ID) in a population. Previous studies have shown that Kayseri is one of the most iodine-deficient areas in Turkey. The aim of this study was to determine the prevalence of goitre, evaluate the degree of ID, its effects on thyroid functions and volume of subjects living in wide outer skirts of the old volcano Erciyes, at 1655 m and 1350 m altitudes. METHODS: UIE was determined in 209 school-age children (SAC) aged between 10 and 14 years and in 183 adults. Thyroid volume (TV) of subjects was performed used by both palpation and ultrasonography (USG). In addition, serum free tri-iodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), thyroglobulin (Tg), anti-Tg and anti thyroid peroxidase (TPO) antibody levels were measured. RESULTS: The prevalence of goitre according to palpation and USG among SAC was found as 50.7 and 58.4% respectively, as 65.0 and 57.9% among adults. Although mean UIC of whole subjects was 30+/-34 microg/l indicated moderate iodine (I) deficiency, 55.4% of the subjects' UIE was <20 microg/l. While the serum fT3, TSH, anti-TPO, Tg levels, body mass index (BMI), TV of SAC and adults (except BMI) with goitre were higher than those of without goitre, serum fT4 and UIE were lower than those of without goitre. CONCLUSIONS: The population living in two areas was exposed to consequences of severe and moderate ID and also endemic goitre due to geographical characteristics of the area. A plan of action including sufficient I intake of people should be planned and be implemented effectively.


Assuntos
Anticorpos/imunologia , Iodeto Peroxidase/imunologia , Iodeto Peroxidase/metabolismo , Iodo/deficiência , Tireoglobulina/imunologia , Tireoglobulina/urina , Adolescente , Adulto , Criança , Feminino , Bócio/epidemiologia , Bócio/urina , Humanos , Iodo/urina , Masculino , Prevalência , Turquia/epidemiologia
7.
Growth Horm IGF Res ; 15(3): 231-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15921942

RESUMO

OBJECTIVE: Growth hormone deficiency (GHD) in adults is associated with abnormal body composition, altered lipid profile, reduced quality of life and osteoporosis. Replacement with recombinant GH results in significant improvements in most of these altered parameters. The most common cause of adult GHD in previous studies was due to pituitary tumors or their treatment. Sheehan's syndrome classically refers to postpartum hypopituitarism due to pituitary necrosis occurring secondary to massive bleeding at or just after delivery. While severe GHD is a well-established feature of Sheehan's syndrome, the effects of Growth hormone replacement therapy (GHRT) in these patients has not been extensively investigated. The present study was therefore designed to investigate the effects of GHD and GHRT in patients with Sheehan's syndrome. DESIGN: The study comprised 14 severely GH-deficient patients with Sheehan's syndrome with a mean age of 49.4+/-7.9 yr. Treatment with GH was started at a dose of 0.15 mg per day in month 1, was increased to 0.30 mg per day in month 2, and was maintained at 0.66 mg per day until the end of month 18. With the similar maintenance dose adequate age adjusted IGF-I levels for each patient has been achieved. Blood pressure, lipid profile, biochemical parameters, anthropometric measurements including body mass index (BMI), waist and waist to hip ratio (W/H), and bone mineral density (BMD) were investigated before and at 3, 6, 12 and 18 months of the GHRT. RESULTS: The duration of GHD from the onset of the disease was 19.4+/-1.6 yr. The majority of the patients (78%) had panhypopituitarism. At baseline mean total cholesterol, LDL-cholesterol and triglyceride levels were higher than the normal reference ranges but HDL-cholesterol levels were within the lower normal range. During the treatment period total cholesterol and LDL-cholesterol levels decreased and HDL-cholesterol levels increased significantly (P < 0.05). Waist circumference and waist to hip ratio were decreased significantly during the GHRT when compared to basal measurements (P < 0.05). There was a significant positive correlation between the basal waist circumference and the duration of GHD (P < 0.05). CONCLUSIONS: This study clearly demonstrates that Sheehan's syndrome is characterized by severe and long-standing GHD. GHRT have beneficial effects in several parameters including lipid profile and waist circumference. But we could not observe any improvement in BMD after 18 months of GHRT. However interpretations of the present results need to be made with caution because of the uncontrolled design. Further placebo controlled studies with high number of patients with Sheehan's syndrome are warranted.


Assuntos
Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/uso terapêutico , Hipopituitarismo/tratamento farmacológico , Adulto , Glicemia/análise , Pressão Sanguínea , Densidade Óssea , Feminino , Hormônio do Crescimento Humano/efeitos adversos , Hormônio do Crescimento Humano/deficiência , Humanos , Fator de Crescimento Insulin-Like I/análise , Lipídeos/sangue , Pessoa de Meia-Idade , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento
8.
Images Paediatr Cardiol ; 7(4): 5-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22368656

RESUMO

Cardiac hemangioma is a rare tumor with a reported incidence of 1-2%. We describe the case of a neonate with a right atrial mass that was diagnosed prenatally. The fetus developed a supraventricular tachycardia and was delivered by cesarean section in the 35(th) week of gestation. The infant underwent surgery after 24 hours to remove the mass which was diagnosed as a cardiac capillary-cavernous hemangioma.

9.
Appl Microbiol Biotechnol ; 66(5): 542-50, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15480636

RESUMO

The gene for the newly described D-amidase from Variovorax paradoxus (Krieg et al. 2002) was cloned and functionally expressed in Escherichia coli. Since native enzyme was available in minute amounts only, we determined the N-terminal sequence of the enzyme and utilized the Universal GenomeWalker Approach to make use of the common internal sequence of the amidase signature family. The high GC content of the gene made it necessary to employ an appropriate DNA polymerase in the amplification reactions. Thus, the sequence of the complete gene and the flanking regions was established. In independent experiments, the gene was then amplified from genomic DNA of V. paradoxus, expressed in E. coli, and characterized. The recombinant enzyme has a specific activity of 1.7 units/mg with racemic tert-leucine amide as substrate and is a homodimer of 49.6-kDa monomers.


Assuntos
Amidoidrolases/genética , Betaproteobacteria/enzimologia , Genes Bacterianos , Amidoidrolases/isolamento & purificação , Sequência de Aminoácidos , Betaproteobacteria/genética , Betaproteobacteria/isolamento & purificação , Clonagem Molecular , DNA Bacteriano/genética , Escherichia coli/genética , Expressão Gênica , Dados de Sequência Molecular , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
10.
Nucl Med Commun ; 24(9): 987-94, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12960598

RESUMO

The aim of this study was to assess the influence of incremental nitroglycerin infusion (NTG+Inf) on the myocardial uptake of 99mTc-tetrofosmin (TF) in order to determine whether nitrates enhance the detection of viable myocardium with TF in patients with coronary artery disease (CAD) and left ventricular dysfunction. Fifty patients (39 males, 11 females; 54 +/- 11 years) with previous myocardial infarction and left ventricular dysfunction, who had been referred for coronary revascularization procedures, were studied. Myocardial single-photon emission tomography (SPET) images were obtained 1 h after injection of 750 MBq TF at baseline and after NTG+Inf, using a 2 day protocol. NTG+Inf was performed starting at 0.4 microg x kg(-1) x min(-1), with equal increments every 5 min up to 2 microg x kg(-1) x min(-1). Within 1 week of the TF study, rest-redistribution (R-RD) 201Tl SPET was performed after the injection of 111 MBq 201Tl. For each study, quantitative analysis was performed in 17 segments. Viability was defined as the presence of tracer uptake of > 50% of the peak activity on baseline studies or reversibility. There was significant correlation between quantitative regional RD 201Tl activity and TF activity after NTG+Inf (r = 0.90, P < 0.001). Of the 131 segments with severely reduced tracer uptake on resting TF images, 34 (26%) were reversible, showing increased tracer uptake after NTG+Inf (from 41%+/-7% to 57%+/-12% of peak activity; P < 0.001). All reversible segments after NTG+Inf had viability criteria on 201Tl studies. There was 95% concordance between TF with NTG+Inf and RD 201Tl imaging with regard to the presence of myocardial viability. We conclude that TF imaging with incremental NTG+Inf improves the detection of ischaemic but viable myocardium, correlating with the viability criteria observed on 201Tl studies. When the advantages of TF imaging are considered, rest TF imaging with NTG+Inf may be a practical diagnostic protocol in patients with CAD and left ventricular dysfunction who are being considered for revascularization.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico por imagem , Nitroglicerina , Compostos Organofosforados , Compostos de Organotecnécio , Tálio , Disfunção Ventricular Esquerda/diagnóstico por imagem , Adulto , Idoso , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/etiologia , Nitroglicerina/administração & dosagem , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Estatística como Assunto , Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/etiologia
11.
Protein Eng ; 15(7): 585-93, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12200541

RESUMO

Benzoylformate decarboxylase (BFD) from Pseudomonas putida was subjected to directed molecular evolution to generate mutants with increased carboligase activity which is a side reaction of the enzyme. After a single round of random mutagenesis mutants were isolated which exhibited a 5-fold increased carboligase activity in aqueous buffer compared to the wild-type enzyme with a high enantiomeric excess of the product (S)-2-hydroxy-1-phenyl-propanone. From the same library, mutants with enhanced carboligase activity in water-miscible organic solvents have been isolated. The selected mutants have been characterized by sequencing, revealing that all mutants carry a mutation at Leu476, which is close to the active site but does not directly interact with the active center. BFD-L476Q has a 5-fold higher carboligase activity than the wild-type enzyme. L476 was subjected to saturation mutagenesis yielding eight different mutants with up to 5-fold increased carboligase activity. Surprisingly, all L476 mutants catalyze the formation of 2-hydroxy-1-phenyl-propanone with significantly higher enantioselectivity than the wild-type enzyme although enantioselectivity was not a selection parameter. Leu476 potentially plays the role of a gatekeeper of the active site of BFD, possibly by controlling the release of the product. The biocatalyst could be significantly improved for its side reaction, the C-C bond formation and for application under conditions that are not optimized in nature.


Assuntos
Carboxiliases/genética , Carboxiliases/metabolismo , Pseudomonas putida/enzimologia , Substituição de Aminoácidos , Pareamento de Bases/genética , Gráficos por Computador , Estabilidade Enzimática , Evolução Molecular , Biblioteca Gênica , Cetonas/química , Cinética , Ligases/metabolismo , Modelos Moleculares , Mutagênese Sítio-Dirigida , Plasmídeos , Ligação Proteica , Estereoisomerismo
12.
Appl Microbiol Biotechnol ; 58(6): 772-80, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12021798

RESUMO

The peptide amidase (Pam) from the gram-negative bacterium Stenotrophomonas maltophilia catalyzes predominantly the hydrolysis of the C-terminal amide bond in peptide amides. Its gene ( pam) was isolated by Southern hybridization using a DNA probe derived from the known N-terminal amino acid sequence. Pam is a member of the amidase signature family and was identified as a periplasmic protein by an N-terminal signal peptide found in the gene. The processed protein consists of 503 amino acids with a molecular mass of 53.5 kDa. The recombinant enzyme with a C-terminal His(6) tag has a monomeric structure and its isoelectric point is 6.3. The dipeptide amide L-Ala- L-Phe-NH(2) is hydrolyzed in the absence of cofactors to L-Ala- L-Phe-OH and ammonia with V(max)=194 U/mg and K(m) <0.5 mM. The natural function of Pam remains unclear. Chymostatin ( K(i)<0.3 microM) and Pefabloc SC ( K(i) not determined) were identified as inhibitors. When the gene was expressed in Escherichia coli on a 12-l scale, the specific activity in the crude extract was 60 U/mg, compared to 0.24 U/mg in S. maltophilia. In the expression system, Pam made up about 31% of the total soluble cell protein. From 75 g wet cells, 2.1 g of >95% pure enzyme was obtained, which corresponds to a total activity of 416,000 units.


Assuntos
Amidoidrolases/genética , Stenotrophomonas maltophilia/genética , Amidoidrolases/química , Amidoidrolases/isolamento & purificação , Amidoidrolases/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Cromatografia em Gel , Clonagem Molecular , Sondas de DNA , Eletroforese em Gel de Poliacrilamida , Inibidores Enzimáticos/farmacologia , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Stenotrophomonas maltophilia/enzimologia , Especificidade por Substrato
13.
Nucl Med Commun ; 23(5): 441-6, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11973484

RESUMO

Chronic hepatitis C virus (HCV) infection has been recently identified as an aetiological agent in idiopathic pulmonary fibrosis. The present study was designed to determine the pulmonary clearance rate of 99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA) in asymptomatic HCV antibody positive (HCV Ab+) patients and the role of 99mTc-DTPA aerosol scintigraphy in the early detection of lung involvement. Twenty-six non-smoker HCV Ab+ and HCV-RNA (+) patients (20 female, six male; aged 43+/-11 years), with no clinical pulmonary symptoms, and normal radiological findings, were studied. Thirty-one healthy non-smoker volunteers (24 female, seven male; aged 40+/-10 years) were taken as a control group. 99mTc-DTPA aerosol inhalation scintigraphy and pulmonary function tests were performed in all patients and in controls. On the basis of the scintigrams the percentage decline in activity per minute (Kep) was evaluated, which represented an accurate parameter of lung membrane permeability. The mean Kep values of healthy controls (0.78+/-0.13 for left lung, 0.79+/-0.14 for right lung) were significantly lower than HCV Ab+ patients (1.10+/-0.31 for left lung, 1.11+/-0.34 for right lung, P<0.001). But no significant change was observed in PFT (P>0.05). We conclude that subclinical alveolitis and/or interstitial lung disease may be present in patients with HCV Ab+, since it is known that an increase in the epithelial permeability of the lung is an early manifestation of interstitial disease.


Assuntos
Hepatite C/diagnóstico por imagem , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/fisiopatologia , Mucosa Respiratória/diagnóstico por imagem , Mucosa Respiratória/metabolismo , Pentetato de Tecnécio Tc 99m , Adulto , Aerossóis , Feminino , Hepatite C/complicações , Hepatite C/metabolismo , Hepatite C/fisiopatologia , Anticorpos Anti-Hepatite C/metabolismo , Humanos , Doenças Pulmonares Intersticiais/etiologia , Doenças Pulmonares Intersticiais/metabolismo , Masculino , Pessoa de Meia-Idade , Permeabilidade , Cintilografia , Compostos Radiofarmacêuticos/farmacocinética , Valores de Referência , Reprodução , Testes de Função Respiratória/métodos , Mucosa Respiratória/fisiopatologia , Sensibilidade e Especificidade , Pentetato de Tecnécio Tc 99m/farmacocinética
14.
Biotechnol Prog ; 17(6): 1128-36, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11735451

RESUMO

The suitability of ion-selective electrodes (ISE) for the determination of residence time distribution (RTD) in turbid, cell-containing fluids was examined. The electrodes were found to give reproducible signals in biomass-containing feedstock with up to 20% wet weight of solids. The enhanced feedstock compatibility of IES, when compared to other tracer sensing devices, allows the study of expanded bed system hydrodynamics under relevant operating conditions. Within the linear range of the corresponding ISE-tracer pair, both examined ISE (Li(+)- or Br(-)-selective) showed to be insensitive against the range of flow rate and pH normally employed during expanded bed adsorption (EBA) of proteins. Analyzing the RTD obtained after a perfect ion tracer pulse in terms of the PDE model (PDE, axially dispersed plug-flow exchanging mass with stagnant zones) gave a quantitative description of the underlying hydrodynamic situation during EBA processing. These data provided a powerful tool to make predictions on the adsorptive global process performance with a defined feedstock type and composition. The link between the hydrodynamic events during feedstock application and the actual process performance was shown when applying intact yeast cell suspensions at different biomass content (up to 7.5% wet weight) and buffer conductivity (5-12 mS) onto an EBA column filled with the adsorbent Streamline Q XL as fluidized phase. On the basis of our experimental results, a guideline for the successful application of the ISE/RTD method to EBA process design is presented.


Assuntos
Brometos/análise , Eletrodos Seletivos de Íons , Lítio/análise , Leveduras/química , Adsorção , Algoritmos , Biomassa , Concentração de Íons de Hidrogênio , Temperatura
15.
Biomacromolecules ; 2(2): 511-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11749214

RESUMO

Fungal hydrophobins are a group of surface active, self-assembling proteins. The filamentous fungus Trichoderma reesei produces two (class II) hydrophobins, HFBI and HFBII. We have studied how these water-soluble hydrophobins behave in two-phase systems using a series of nonionic surfactants with different characteristics. It was found that both hydrophobins, but especially HFBI, had a very high affinity for the surfactants. The highest partitioning coefficient, over 2500, was observed for HFBI with C(11)EO(2). Reducing the disulfides in the protein resulted in a complete loss of affinity for the surfactant, which demonstrates that the interaction is dependent on the disulfide-stabilized conformation. The hydrophobins could be efficiently extracted back from the surfactant phase by addition of alcohols such as isobutanol. Effects of the type of surfactant, temperature, pH, and ionic strength were investigated. The use of this method for purifying the proteins from crude fungal culture supernatants is demonstrated and implications of the protein-polymer interaction are discussed.


Assuntos
Proteínas Fúngicas/isolamento & purificação , Tensoativos/química , Trichoderma/química , Cromatografia Líquida de Alta Pressão , Proteínas Fúngicas/biossíntese , Genes Fúngicos/genética , Trichoderma/genética , Trichoderma/metabolismo
16.
Alcohol Alcohol ; 36(6): 572-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11704624

RESUMO

Endogenous opioid peptides are thought to participate in the phenomena of alcohol tolerance and withdrawal. Since in the pituitary gland, beta-endorphin (beta-EP) and adrenocorticotropic hormone (ACTH) are produced from the same precursor molecule, pro-opiomelanocortin, it may be expected that alterations in plasma ACTH and cortisol levels should parallel changes in plasma beta-EP levels during alcohol withdrawal. The aim of the present study was to investigate the alterations of beta-EP, ACTH and cortisol secretion patterns in alcohol-dependent patients with heavy intake in the early withdrawal period and, if any, whether these changes remained stable on long-term withdrawal. Twenty-two hospitalized male patients (mean age +/- SD: 43.45 +/- 9.22 years, mean daily amount of alcohol +/- SD: 421.59 +/- 116.57 g) who were diagnosed to have alcohol withdrawal and 20 age-matched healthy men (mean age +/- SD: 38.35 +/- 7.63 years) were included in the study. Morning and night levels of plasma beta-EP, ACTH and cortisol were measured in the patients during the early (first week) and late (fourth week) withdrawal periods following alcohol cessation, and only once in the control subjects. It was found that both morning beta-EP and morning ACTH levels were reduced during both early and late withdrawals, whereas cortisol levels were increased in early withdrawal and normalized towards the late withdrawal period. The finding that beta-EP deficiency continued despite withdrawal symptoms subsiding in patients suggests that their beta-EP deficiency is independent of the withdrawal syndrome and that reduced beta-EP activity may be a trait contributing to alcohol craving.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Etanol/efeitos adversos , Hidrocortisona/sangue , Síndrome de Abstinência a Substâncias/sangue , Síndrome de Abstinência a Substâncias/etiologia , beta-Endorfina/sangue , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Síndrome de Abstinência a Substâncias/diagnóstico
17.
Acta Obstet Gynecol Scand ; 80(11): 1009-13, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11703197

RESUMO

BACKGROUND: The aim of this study was to measure the circulating levels of androgens in the third trimester of pregnancy and six weeks after delivery and to discuss androgen contribution in the pathogenesis of preeclampsia. METHODS: Twenty-two preeclamptic and 20 normotensive women completed this prospective study. Blood samples were drawn in the third trimester (28-32 gestational weeks) and six weeks after delivery. Serum total testosterone (T), free testosterone (fT) dehydroepiandrosterone sulfate (DHEAS), androstenodione (A), sex hormone binding globulin (SHBG) and estradiol (E2) levels were measured. The statistical analyses of the data were performed by using Wilcoxon Rank test within the groups, Student unpaired t test and Chi-square test between the groups with the SPSS program. RESULTS: T and fT levels were found to be significantly higher (p<0.05) in preeclamptic women in the third trimester compared to the values of normotensive controls. However, there were significant decreases (p<0.05) in T and fT levels six weeks after delivery, reaching values not significantly different from normotensive subjects (p>0.05). Furthermore, SHBG, DHEAS, A and E2 levels were not significantly different (p>0.05) between the groups in the third trimester or six weeks after delivery. CONCLUSION: We conclude that higher blood androgen levels measured in preeclamptic patients may be implicated in the pathogenesis of preeclampsia.


Assuntos
Androgênios/sangue , Pré-Eclâmpsia/sangue , Adulto , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Feminino , Humanos , Gravidez , Terceiro Trimestre da Gravidez , Estudos Prospectivos , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue
18.
J Biochem Biophys Methods ; 49(1-3): 533-52, 2001 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-11694300

RESUMO

Formate dehydrogenase (FDH) is an enzyme of industrial interest, which is recombinantly expressed as an intracellular protein in Escherichia coli. In order to establish an efficient and reliable purification protocol, an expanded bed adsorption (EBA) process was developed, starting from the crude bacterial homogenate. EBA process design was performed with the goal of finding operating conditions which, on one hand, allow efficient adsorption of the target protein and which, on the other hand, support the formation of a perfectly classified fluidised bed (expanded bed) in the crude feed solution. A pseudo-affinity ligand (Procion Red HE3B) was used to bind the FDH with high selectivity and reasonable capacity (maximum equilibrium capacity of 30 U/ml). Additionally, a simplified modelling approach, involving small packed beds for generation of process parameters, was employed for defining the operating conditions during sample application. In combination with extended elution studies, a process was set up, which could be scaled up to 7.5 l of adsorbent volume yielding a total amount of 100,000 U of 94% pure FDH per run. On this scale, 19 l of a benzonase-treated E. coli homogenate of 15% wet-weight (pH 7.5, 9 mS/cm conductivity) were loaded to the pseudo-affinity adsorbent (0.25 m sed. bed height, 5 x 10(-4) m/s fluid velocity). After a series of two wash steps, a particle-free eluate pool was obtained with 85% yield of FDH. This excellently demonstrates the suitability of expanded bed adsorption for efficient isolation of proteins by combining solid-liquid separation with adsorptive purification in a single unit operation.


Assuntos
Formiato Desidrogenases/isolamento & purificação , Adsorção , Cromatografia de Afinidade/métodos , Cromatografia por Troca Iônica , Escherichia coli/enzimologia , Formiato Desidrogenases/metabolismo , Indicadores e Reagentes , Cinética , Ligantes , Ligação Proteica , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
19.
Nucl Med Commun ; 22(12): 1317-24, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11711902

RESUMO

Resting (99m)Tc-tetrofosmin (TF) uptake was compared with thallium ((201)Tl) rest-redistribution (R-RD) uptake in patients with previous myocardial infarction (MI) and significant coronary artery disease (CAD) to assess the ability of TF to detect viable myocardium. We studied 30 patients (21 males and nine females, mean age 53.9+/-12.5 years) with prior MI and left ventricular dysfunction who had been referred for coronary revascularization procedures. Myocardial single photon emission computed tomography (SPECT) images were obtained 1 h after injection of 750 MBq of TF. Within 1 week of the TF study, R-RD (201)Tl SPECT imaging was performed after injection of 111 MBq of (201)Tl . Quantitative analysis was performed in 21 segments. Viability was defined as the presence of tracer uptake greater than 50% of the peak activity on baseline studies or after reversibility. There was significant correlation between the quantitative regional R-RD (201)Tl activity and the resting TF activity (r=0.88, P<0.001). Quantitative analysis showed that the uptake of the two tracers was comparable in normal segments as well as in segments with fixed (201)Tl defects. In contrast, in segments with reversible (201)Tl defects, TF uptake was significantly greater than resting (201)Tl uptake, but lower than R-RD (201)Tl uptake. There were 52 segments (47% of the severely reduced segments on TF images) that showed no viability with TF, but were viable on the redistribution (201)Tl studies. We conclude that quantitative resting TF SPECT underestimates the presence of viable myocardium compared with R-RD (201)Tl imaging on the basis of using 50% of the peak activity as the viability threshold.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico por imagem , Compostos Organofosforados/farmacocinética , Compostos de Organotecnécio/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Radioisótopos de Tálio/farmacocinética , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Transporte Biológico , Doença das Coronárias/metabolismo , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/metabolismo , Revascularização Miocárdica , Distribuição Tecidual , Disfunção Ventricular Esquerda/diagnóstico por imagem , Cicatrização
20.
Biotechnol Prog ; 17(3): 503-12, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11386872

RESUMO

The purification of human chymotrypsinogen B (hCTRB) after expression and secretion by the yeast Pichia pastoris is described based on two different approaches using integrated initial recovery. Extraction employing aqueous two-phase systems (ATPS) from poly(ethylene glycol) and sodium sulfate allows direct processing of cell containing yeast suspensions of 50% wet weight. The target protein is obtained partially purified in the top phase while cells and cell debris are partitioned to the bottom phase of the system. hCTRB is further purified by adsorption from the top phase to the cation exchanger SP Sepharose Big Beads and elution in a salt step. The single step isolation of hCTRB is possible by expanded bed adsorption (EBA) using a fluidized cation exchanger (Streamline SP XL). A design strategy is shown taking both target protein binding and stable fluidization of the stationary phase in cell containing suspensions into consideration. For the example of hCTRB isolation from cell containing P. pastoris suspensions, a successful use of this strategy is demonstrated. Both initial recovery strategies deliver a product that can be further purified and formulated by ultrafiltration/diafiltration followed by lyophilization, resulting in a homogeneous product. Scale-up to 30-90 L of culture suspension was shown for both methods, resulting in a product of similar quality. Comparing both strategies reveals that the two-step ATPS route is better suited for high cell density cultures, while the single step EBA method is preferred for cultures of moderate cell density. This is due to the fact that application of EBA is restricted to suspensions of 10-12.5% wet weight cell concentration, thus necessitating dilution of the original broth prior to sample application. The data presented show that integrated recovery operations are a valuable alternative to traditional processing for systems that are problematic during initial solid-liquid separation.


Assuntos
Quimotripsinogênio/isolamento & purificação , Quimotripsinogênio/metabolismo , Microbiologia Industrial/métodos , Pichia/metabolismo , Quimotripsinogênio/genética , Fermentação , Humanos , Microbiologia Industrial/instrumentação , Pichia/genética , Projetos Piloto , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
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