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1.
Medicina (B.Aires) ; 83(supl.4): 57-62, oct. 2023.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1521203

ABSTRACT

Resumen Las Epilepsias Focales Autolimitadas de la Infancia (SELFEs - siglas en inglés) son los síndromes electroclíni cos más prevalentes en edad pediátrica, cuya evolución típica, con inicio y remisión dependientes de la edad, ha permitido que el Grupo de Trabajo de Nosología y Definiciones de la ILAE (2022) las defina como "Epilep sias focales autolimitadas de la infancia", estableciendo así, criterios de alerta y exclusión para estandarizar su diagnóstico. Dentro de estos síndromes se incluyen: la Epilepsia Autolimitada con Espigas Centrotemporales (previamente Epilepsia Rolándica), Epilepsia Autolimi tada con Crisis Autonómicas. (previamente Síndrome de Panayiotopoulos), Epilepsia Visual Occipital Infantil (previamente Síndrome de Gastaut), y Epilepsia Fotosen sible del Lóbulo occipital. Ya no se recomienda utilizar el término "benignas" para referirse a ellas, ya que esto haría caso omiso de las comorbilidades que padecen algunos individuos. Asimismo, el término "idiopático" sólo se utiliza ahora para denominar a los síndromes clasificados como Epilepsias Generalizadas Idiopáticas.


Abstract Self-limited Focal Epilepsies of Childhood (SELFEs) are the most prevalent electroclinical syndromes in pe diatric age, whose typical evolution, with age-dependent onset and remission, has allowed the ILAE Nosology and Definitions Working Group (2022) to define them as "Self-limited Focal Epilepsies of Childhood", thus establishing alert and exclusion criteria to standardize their diagno sis. These syndromes include: Self-limited Epilepsy with Centrotemporal Spikes (previously Rolandic Epilepsy), Self-limited Epilepsy with Autonomic Seizures (previ ously Panayiotopoulos Syndrome), Childhood Occipital Visual Epilepsy, (previously Gastaut Syndrome), and Photosensitive Occipital Lobe Epilepsy. Using the term "benign" to refer to them is no longer recommended, as this would ignore the comorbidities some individuals suffer. Also, the term "idiopathic" is now only used to refer to the syndromes classified as Idiopathic General ized Epilepsies.

2.
Medicina (B Aires) ; 83 Suppl 4: 57-62, 2023 Sep.
Article in Spanish | MEDLINE | ID: mdl-37714124

ABSTRACT

Self-limited Focal Epilepsies of Childhood (SELFEs) are the most prevalent electroclinical syndromes in pediatric age, whose typical evolution, with age-dependent onset and remission, has allowed the ILAE Nosology and Definitions Working Group (2022) to define them as "Selflimited Focal Epilepsies of Childhood", thus establishing alert and exclusion criteria to standardize their diagnosis. These syndromes include: Self-limited Epilepsy with Centrotemporal Spikes (previously Rolandic Epilepsy), Self-limited Epilepsy with Autonomic Seizures (previously Panayiotopoulos Syndrome), Childhood Occipital Visual Epilepsy, (previously Gastaut Syndrome), and Photosensitive Occipital Lobe Epilepsy. Using the term "benign" to refer to them is no longer recommended, as this would ignore the comorbidities some individuals suffer. Also, the term "idiopathic" is now only used to refer to the syndromes classified as Idiopathic Generalized Epilepsies.


Las Epilepsias Focales Autolimitadas de la Infancia (SELFEs - siglas en inglés) son los síndromes electroclínicos más prevalentes en edad pediátrica, cuya evolución típica, con inicio y remisión dependientes de la edad, ha permitido que el Grupo de Trabajo de Nosología y Definiciones de la ILAE (2022) las defina como "Epilepsias focales autolimitadas de la infancia", estableciendo así, criterios de alerta y exclusión para estandarizar su diagnóstico. Dentro de estos síndromes se incluyen: la Epilepsia Autolimitada con Espigas Centrotemporales (previamente Epilepsia Rolándica), Epilepsia Autolimitada con Crisis Autonómicas. (previamente Síndrome de Panayiotopoulos), Epilepsia Visual Occipital Infantil (previamente Síndrome de Gastaut), y Epilepsia Fotosensible del Lóbulo occipital. Ya no se recomienda utilizar el término "benignas" para referirse a ellas, ya que esto haría caso omiso de las comorbilidades que padecen algunos individuos. Asimismo, el término "idiopático" sólo se utiliza ahora para denominar a los síndromes clasificados como Epilepsias Generalizadas Idiopáticas.


Subject(s)
Epilepsies, Partial , Epilepsy, Generalized , Lennox Gastaut Syndrome , Humans , Child , Epilepsies, Partial/diagnosis , Seizures/diagnosis
3.
Mater Sci Eng C Mater Biol Appl ; 116: 111268, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32806245

ABSTRACT

Biocompatible and antibacterial multi-layer coatings of hydroxyapatite (HA)-Ag/SiO2/TiN/Ti were obtained on the Ti-6Al-4V alloy, by means of the magnetron sputtering technique. During characterization of the coatings, the chemical composition was evaluated by energy dispersive X-ray spectroscopy and the phase analysis was carried out by X-ray diffraction. The morphology of the coatings was observed by field emission scanning electron microscopy, while transmission electron microscopy was used to appreciate their structure. The adhesion of the coatings to the substrate was evaluated by micro scratch test. The in vitro biological response was evaluated in terms of cytotoxicity, adhesion and differentiation of mouse mesenchymal stem cells, as well as adhesion and bacterial viability of Staphylococcus aureus strain. Through the compositional study carried out, the deposition of the HA phase was verified, with a Ca/P ratio close to 1.67 and the characteristic diffraction peaks of this compound. The structural study of the coatings evidenced the obtention of multi-layer architectures. The use of an intermediate SiO2/TiN/Ti trilayer was found to improve adhesion between HA-Ag and the substrate by 84%. Finally, the in vitro biological tests carried out indicated a potentially non-toxic character in the coatings. Additionally, an antibacterial effect was registered at low concentrations of Ag (<0.25 mg/L).


Subject(s)
Durapatite , Titanium , Animals , Mice , Anti-Bacterial Agents/pharmacology , Coated Materials, Biocompatible/pharmacology , Materials Testing , Microscopy, Electron, Scanning , Silicon Dioxide , Silver/pharmacology , Titanium/pharmacology , X-Ray Diffraction
4.
Semergen ; 41(6): 296-304, 2015 Sep.
Article in Spanish | MEDLINE | ID: mdl-25242238

ABSTRACT

OBJECTIVE: As there are few studies on the smoking habits of specialists training in health sciences (residents), it is of interest to determine the prevalence of smoking, nicotine dependence and motivation for change, and their relationship with other variables (personal, work and consumption of other drugs). MATERIAL AND METHODS: A multicentre, cross-sectional study using a questionnaire was conducted in 2012. All the residents who were studying in Teaching Health Centres in Andalusia (Spain) completed a questionnaire, which was sent by e-mail, collecting: age, sex, specialty, country of origin, qualitative-quantitative consumption of tobacco, age of onset/cessation, Fagerström test and stage of change (Proschaka). RESULTS: A total of 2667 residents (63% of total) completed the questionnaire. The mean age was 29.1 years (± 5.2), 69% female, 89% Spanish, and 86% physicians. Of the 17% who smoked (daily pattern-47%, intermittently-41%, related to leisure-3%), starting at 17.4 years (±3.5) and mean of 7.5 cigarettes per day (±7.1), higher medical specialties (P=.067 ANOVA), and in men (P=.074, Student-t). More than three-quarters (82%) had a low nicotine dependence, being higher in hospital medical specialties (P=.078 χ(2)). Of the total, 7% were former smokers, and 48% wanted to quit smoking (contemplation 38%, preparation 10%). In the multivariate analysis there was a link between smoking and alcohol consumption (OR 2.84) and illegal drugs (OR 3.57). There were no differences by age or country. CONCLUSIONS: The consumption of tobacco in residents is less than the general population, with a low dependence and better willingness to change. The period of specialised training is a good time to offer tobacco interventions.


Subject(s)
Internship and Residency/statistics & numerical data , Motivation , Smoking/epidemiology , Tobacco Use Disorder/epidemiology , Adult , Cross-Sectional Studies , Female , Humans , Male , Smoking/psychology , Smoking Cessation/psychology , Spain , Surveys and Questionnaires , Tobacco Use Disorder/psychology , Young Adult
5.
Semergen ; 41(3): 139-48, 2015 Apr.
Article in Spanish | MEDLINE | ID: mdl-25002349

ABSTRACT

OBJECTIVES: Primary: To determine the differences, by occupational category and province, in the knowledge and attitudes of health professionals on the Living Wills Document (LWD) in 4 Andalusian provinces: Cordoba, Jaen, Cadiz, and Granada. Secondary: To determine the number of documents prepared in these areas and the number consulted in terminal situations. MATERIAL AND METHODS: Descriptive observational multicenter study, with 17 health areas in 4 Andalusian provinces. TARGET POPULATION: Family doctors, nurses and social workers of the areas studied (n=340). Interventions Validated self-administered questionnaire about advance directives. Descriptive and bivariate (×2) analysis of data was performed. RESULTS: Mean age 46±8.8 years, 53.2% women. Physicians 56.1%, nurses 41.1%, social workers 2.6%. The mean score (0-10) of their knowledge was 5.42±2.41, with 78.4% believing that LWD are regulated in Andalusia (provinces differences, P=.001). More than one-third (36.7%) had read the document (differences by occupation, P=.001). The mean score on the advantage of preparing a LWD for the patient was 8.27±2.16 (significant differences between provinces P=.02). Mean score about the practitioner would respect the wishes of a patient in a LWD was 9.14±1.64 (significant difference between provinces P=.03). The mean score of the question about expressing the desires of the professional on preparing their LWD in the following year was 4.85±3.74 (P=.02). CONCLUSIONS: There are different behaviors between professions on reading the LWD. There are differences between provinces in the following aspects: whether the documents are regulated, whether the professionals prepare the LWD, and whether the professionals respects the provisions of the LWD.


Subject(s)
Advance Directives , Attitude of Health Personnel , Health Knowledge, Attitudes, Practice , Living Wills , Adult , Female , Humans , Male , Middle Aged , Nurses/statistics & numerical data , Physicians/statistics & numerical data , Social Workers/statistics & numerical data , Spain , Surveys and Questionnaires
6.
Appl Microbiol Biotechnol ; 96(5): 1291-300, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22669633

ABSTRACT

In this work, Escherichia coli MG1655 was engineered to produce ethanol and evolved in a laboratory process to obtain an acetate tolerant strain called MS04 (E. coli MG1655: ΔpflB, ΔadhE, ΔfrdA, ΔxylFGH, ΔldhA, PpflB::pdc ( Zm ) -adhB ( Zm ), evolved). The growth and ethanol production kinetics of strain MS04 were determined in mineral medium, mainly under non-aerated conditions, supplemented with glucose in the presence of different concentrations of sodium acetate at pH 7.0 and at different values of acid pH and a constant concentration of sodium acetate (2 g/l). Results revealed an increase in the specific growth rate, cell mass formation, and ethanol volumetric productivity at moderate concentrations of sodium acetate (2-10 g/l), in addition to a high tolerance to acetate because it was able to grow and produce a high yield of ethanol in the presence of up to 40 g/l of sodium acetate. Genomic analysis of the ΔpflB evolved strain identified that a chromosomal deletion of 27.3 kb generates the improved growth and acetate tolerance in MG1655 ΔpflB derivative strains. This deletion comprises genes related to the respiration of nitrate, repair of alkylated DNA and synthesis of the ompC gene coding for porin C, cytochromes C, thiamine, and colonic acid. Strain MS04 is advantageous for the production of ethanol from hemicellulosic hydrolysates that contain acetate.


Subject(s)
Acetates/toxicity , Drug Tolerance , Escherichia coli/metabolism , Ethanol/metabolism , Glucose/metabolism , Metabolic Engineering , Minerals/metabolism , Aerobiosis , Biomass , Chromosomes, Bacterial , Culture Media/chemistry , Escherichia coli/drug effects , Escherichia coli/growth & development , Gene Deletion , Genome, Bacterial , Genomics , Hydrogen-Ion Concentration
7.
Curr Med Chem ; 18(1): 79-90, 2011.
Article in English | MEDLINE | ID: mdl-21110813

ABSTRACT

Globally, diabetes and obesity are two of the most common metabolic diseases of the 21(st) century. Increasingly, not only adults but children and adolescents are being affected. New approaches are needed to prevent and treat these disorders and to reduce the impact of associated disease-related complications. Industrial-scale production using plant-root cultures can produce quantities and quality of inexpensive bioactive small molecules with nutraceutical and pharmaceutical properties. Using this approach, and targeting these diseases, a next generation approach to tackling this emerging global health crisis may be developed. Adventitious roots cultured in bioreactors under controlled and reproducible conditions have been shown effective for production of natural products. The liquid-phase airlift bioreactor in particular has been used successfully for culturing roots on an industrial-scale and thus may provide an economical production platform for expressing promising plant-based antidiabetic and antioxidant molecules. This review focuses on a next-generation, scalable, bioprocessing approach for adventitious and hairy root cultures that are a pesticide-free, seasonally-independent, plant-based source of three molecules that have shown promise for the therapeutic management of diabetes and obesity: corosolic acid, resveratrol and ginsenosides.


Subject(s)
Antioxidants/metabolism , Bioreactors , Hypoglycemic Agents/metabolism , Antioxidants/chemistry , Antioxidants/pharmacology , Arachis/cytology , Arachis/metabolism , Biotechnology , Ginsenosides/biosynthesis , Ginsenosides/chemistry , Ginsenosides/pharmacology , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/pharmacology , Plant Roots/cytology , Plant Roots/metabolism , Resveratrol , Stilbenes/chemistry , Stilbenes/pharmacology , Triterpenes/chemistry , Triterpenes/pharmacology
8.
Arq Bras Cardiol ; 94(3): 357-63, 378-84, 2010 Mar.
Article in English, Portuguese | MEDLINE | ID: mdl-20730266

ABSTRACT

BACKGROUND: The presence of anemia and renal dysfunction grants a bad prognosis for patients with heart failure and reduced ejection fraction (HFREF). The impact on patients with heart failure and normal ejection fraction (HFNEF) is not widely studied. OBJECTIVES: To study the prevalence and the prognosis of anemia and renal dysfunction (RD) in patients with heart failure according to the type of ventricular dysfunction. METHODS: A total of 209 patients with chronic and stable heart failure were prospectively studied. Individuals with ejection fraction <50% were considered as HFREF patients. Anemia was defined, based on WHO criteria, as hemoglobin <13 g/dl for men and <12 g/dl for women. Renal function was calculated by means of the Simplified Modified Diet Renal Disease (sMDRD) formula. Hospitalizations, emergency admittances and obit by cardiac causes were considered as cardiac events. RESULTS: Ninety patients had HFREF and 119 had HFNEF. The glomerular filtration rate (GFR) was smaller in HFREF group (57.6 +/- 66.2 versus 94.8 +/- 36.6 ml/min/1.73m(2); p=0.01). There was no difference in the prevalence of anemia between groups (23.3% versus 18.5%; p=0.34). Moderate to severe RD prevalence was higher in HFREF group (32.2% versus 16.8%; p=0.01). RD was the only factor associated with anemia that was independently associated with cardiac events (HR 2.52; 95%CI=1.27-5.2; p=0.01). CONCLUSION: RD was less prevalent in HFNEF, while the prevalence of anemia did not differ between groups. RD was predictor of cardiac events independently on ejection fraction.


Subject(s)
Anemia/epidemiology , Heart Failure/complications , Renal Insufficiency/epidemiology , Stroke Volume/physiology , Aged , Anemia/diagnosis , Anemia/etiology , Brazil/epidemiology , Female , Heart Failure/physiopathology , Humans , Male , Middle Aged , Prevalence , Prognosis , Prospective Studies , Renal Insufficiency/diagnosis , Renal Insufficiency/etiology , Sex Factors
9.
Arq. bras. cardiol ; 94(3): 378-384, mar. 2010. tab, ilus
Article in Portuguese | LILACS | ID: lil-545826

ABSTRACT

FUNDAMENTO: A presença de anemia e de disfunção renal confere mau prognóstico em pacientes com insuficiência cardíaca (IC) e fração de ejeção reduzida (ICFER). O impacto em pacientes com IC e fração de ejeção normal (ICFEN) é pouco estudado. OBJETIVOS: Estudar a prevalência e o prognóstico da anemia e da disfunção renal (DR) em pacientes com IC de acordo com o tipo de disfunção ventricular. MÉTODOS: Foram estudados prospectivamente 209 pacientes com IC crônica estável. Pacientes com fração de ejeção <50 por cento foram considerados como tendo ICFER. Anemia foi definida pelos critérios da OMS como hemoglobina <13 g/dl em homens e <12 g/dl em mulheres. A função renal foi calculada pela fórmula sMDRD (Simplified Modified Diet Renal Disease). Hospitalizações, visitas a emergências e óbitos por causas cardíacas foram considerados como eventos cardíacos. RESULTADOS: Noventa pacientes tinham ICFER e 119, ICFEN. A taxa de filtração glomerular (TFG) foi menor no grupo com ICFER (57,6 ± 66,2 versus 94,8 ± 36,6 ml/min/1,73m²; p=0,01). Não houve diferença na prevalência da anemia nos dois grupos (23,3 por cento versus 18,5 por cento; p=0,34). A prevalência da DR moderada a grave foi maior no grupo com ICFER (32,2 por cento versus 16,8 por cento p=0,01). A DR foi o único fator associado à anemia e associou-se independentemente com eventos cardíacos (HR 2,52; IC 95 por cento = 1,27 - 5,2; p=0,01). CONCLUSÃO: DR foi menos prevalente na ICFEN, enquanto a prevalência de anemia não diferiu entre os dois grupos. A DR foi preditora de eventos cardíacos, independentemente da fração de ejeção.


BACKGROUND: The presence of anemia and renal dysfunction grants a bad prognosis for patients with heart failure and reduced ejection fraction (HFREF). The impact on patients with heart failure and normal ejection fraction (HFNEF) is not widely studied. OBJECTIVES: To study the prevalence and the prognosis of anemia and renal dysfunction (RD) in patients with heart failure according to the type of ventricular dysfunction. METHODS: A total of 209 patients with chronic and stable heart failure were prospectively studied. Individuals with ejection fraction <50 percent were considered as HFREF patients. Anemia was defined, based on WHO criteria, as hemoglobin <13 g/dl for men and <12 g/dl for women. Renal function was calculated by means of the Simplified Modified Diet Renal Disease (sMDRD) formula. Hospitalizations, emergency admittances and obit by cardiac causes were considered as cardiac events. RESULTS: Ninety patients had HFREF and 119 had HFNEF. The glomerular filtration rate (GFR) was smaller in HFREF group (57.6 ± 66.2 versus 94.8 ± 36.6 ml/min/1.73m²; p=0.01). There was no difference in the prevalence of anemia between groups (23.3 percent versus 18.5 percent; p=0.34). Moderate to severe RD prevalence was higher in HFREF group (32.2 percent versus 16.8 percent; p=0.01). RD was the only factor associated with anemia that was independently associated with cardiac events (HR 2.52; 95 percentCI=1.27-5.2; p=0.01). CONCLUSION: RD was less prevalent in HFNEF, while the prevalence of anemia did not differ between groups. RD was predictor of cardiac events independently on ejection fraction.


Subject(s)
Aged , Female , Humans , Male , Middle Aged , Anemia/epidemiology , Heart Failure/complications , Renal Insufficiency/epidemiology , Stroke Volume/physiology , Anemia/diagnosis , Anemia/etiology , Brazil/epidemiology , Heart Failure/physiopathology , Prevalence , Prognosis , Prospective Studies , Renal Insufficiency/diagnosis , Renal Insufficiency/etiology , Sex Factors
10.
J Appl Microbiol ; 101(5): 1002-8, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17040223

ABSTRACT

AIMS: A parametric study was conducted to define optimum conditions to achieve high yields in the conversion of tyrosine to eumelanin (EuMel) using recombinant Escherichia coli. METHODS AND RESULTS: Escherichia coli W3110 (pTrcMutmelA) expressing the tyrosinase coding gene from Rhizobium etli and glucose-mineral media were used to transform tyrosine into EuMel. Batch aerobic fermentor cultures were performed to study the effect of temperature, pH and inducer concentration (isopropyl-D-thio-galactopyranoside) on melanin production. Under optimum conditions, 0.1 mmol l(-1) of isopropyl-D-thio-galactopyranoside, temperature of 30 degrees C, and changing pH from 7.0 to 7.5 during the production phase, a 100% conversion of tyrosine into EuMel is obtained. Furthermore, tyrosine feeding allowed us to obtain the highest level (6 g l(-1)) of EuMel produced by recombinant E. coli reported until now. CONCLUSIONS: The most important factors affecting melanin formation and hence influencing the rate and efficiency in the conversion of tyrosine into EuMel in this system, are the temperature and pH. SIGNIFICANCE AND IMPACT OF THE STUDY: Maximum theoretical yield was obtained using a simple culture process and mineral media to convert tyrosine (a medium value compound) into melanin, a high value compound. The process reported here avoids the use of purified tyrosinase, expensive chemical methods or the cumbersome extraction of this polymer from animal or plant tissues.


Subject(s)
Escherichia coli/metabolism , Melanins/biosynthesis , Recombinant Proteins/biosynthesis , Ampicillin/pharmacology , Ampicillin Resistance , Anti-Bacterial Agents/pharmacology , Bioreactors , Culture Media , Dose-Response Relationship, Drug , Escherichia coli/drug effects , Escherichia coli/genetics , Glucose , Hydrogen-Ion Concentration , Isopropyl Thiogalactoside/pharmacology , Protein Engineering/methods , Rhizobium etli/genetics , Temperature , Tyrosine/genetics , Tyrosine/metabolism
11.
Plant Cell Rep ; 22(6): 437-41, 2004 Jan.
Article in English | MEDLINE | ID: mdl-13680137

ABSTRACT

Camptothecin (CPT) is an anticancer and antiviral alkaloid produced by the Chinese tree Camptotheca acuminata (Nyssaceae) and some other species belonging to the families Apocynaceae, Olacaceae, and Rubiaceae. Bark and seeds are currently used as sources for the drug. Several attempts have been made to produce CPT from cell suspensions; however, the low yields obtained limit this approach. Cultures of differentiated cell types may be an alternative source of alkaloid production. Hairy root cultures of C. acuminata were established from tissue transformed with Agrobacterium rhizogenes strains ATCC 15834 and R-1000. Integration of the genes responsible for the hairy-root phenotype ( rol genes) into the plant genome was verified by DNA gel blot analysis. The hairy roots produce and secrete CPT as well as the more potent and less toxic natural derivative, 10-hydroxycamptothecin (HCPT), into the medium. Remarkably, the cultures were able to synthesize the alkaloids at levels equal to, and sometimes greater than, the roots in planta, i.e., 1.0 and 0.15 mg/g dry weight for CPT and the HCPT, respectively.


Subject(s)
Camptotheca/chemistry , Camptothecin/analogs & derivatives , Camptothecin/analysis , Plant Roots/chemistry , Alkaloids/chemistry , Alkaloids/isolation & purification , Camptotheca/genetics , Camptothecin/metabolism , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , Genome, Plant , Phenotype , Plants, Genetically Modified , Rhizobium/genetics
12.
Metab Eng ; 4(2): 124-37, 2002 Apr.
Article in English | MEDLINE | ID: mdl-12009792

ABSTRACT

We have developed Escherichia coli strains that internalize glucose utilizing the GalP permease instead of the phosphoenolpyruvate:carbohydrate phosphotransferase system. It has been demonstrated that a strain with these modifications (PTS(-)Glc(+)) can direct more carbon flux into the aromatic pathway than the wild-type parental strain (N. Flores et al., 1996, Nat. Biotechnol. 14, 620-623; G. Gosset et al., 1996, J. Ind. Microbiol. 17, 47-52; J. L. Baéz et al., 2001, Biotechnol. Bioeng. 73, 530-535). In this study, we have determined and compared the carbon fluxes of a wild-type strain (JM101), a PTS(-)Glc(-) strain, and two isogenic PTS(-)Glc(+) derivatives named PB12 and PB13 by combining genetic, biochemical, and NMR approaches. It was determined that in these strains a functional glk gene in the chromosome is required for rapid glucose consumption; furthermore, glucokinase-specific activities were higher than in the wild-type strain. (13)C labeling and NMR analysis allowed the determination of differences in vivo which include higher glycolytic fluxes of 93.1 and 89.2% compared with the 76.6% obtained for the wild-type E. coli. In PB12 and PB13 we found a flux through the malic enzymes of 4 and 10%, respectively, compared to zero in the wild-type strain. While flux through the Pck enzyme was absent in PB12 and PB13, in the wild type it was 7.7%. Finally, it was found that in the JM101 and PB12 strains both the oxidative and the nonoxidative branches of the pentose phosphate pathway contributed to ribose 5-phosphate synthesis, whereas in PB13 this pentose was synthesized almost exclusively through the oxidative branch. The determined carbon fluxes correlate with biochemical and genetic characterizations.


Subject(s)
Carbon/metabolism , Escherichia coli/metabolism , Biomedical Engineering , Carbon Isotopes , Escherichia coli/genetics , Glucokinase/metabolism , Glucose/metabolism , Magnetic Resonance Spectroscopy , Membrane Transport Proteins/metabolism , Monosaccharide Transport Proteins , Mutation , Pentose Phosphate Pathway , Phosphoenolpyruvate Sugar Phosphotransferase System/metabolism
13.
Appl Microbiol Biotechnol ; 57(1-2): 186-91, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11693918

ABSTRACT

Due to catabolite repression in microorganisms, sugar mixtures cannot be metabolized in a rapid and efficient manner. Therefore, the development of mutant strains that avoid this regulatory system is of special interest to fermentation processes. In the present study, the utilization of sugar mixtures by an Escherichia coli mutant strain devoid of the phosphotransferase system (PTS) was characterized. This mutant can transport glucose (PTS- Glucose+ phenotype) by a non-PTS mechanism as rapidly as its wild-type parental strain. In cultures grown in minimal medium supplemented with glucose-xylose or glucose-arabinose mixtures, glucose repressed arabinose- or xylose-utilization in the wild-type strain. However, under the same culture conditions with the PTS- Glucose+ mutant, glucose and arabinose were co-metabolized, but glucose still exerted a partial repressive effect on xylose consumption. In cultures growing with a triple mixture of glucose-arabinose-xylose, the wild-type strain sequentially utilized glucose, arabinose and finally, xylose. In contrast, the PTS- Glucose+ strain co-metabolized glucose and arabinose, whereas xylose was utilized after glucose-arabinose depletion. As a result of glucose-arabinose co-metabolism, the PTS- Glucose+ strain consumed the total amount of sugars contained in the culture medium 16% faster than the wild-type strain. [14C]-Xylose uptake experiments showed that in the PTS- Glucose+ strain, galactose permease increases xylose transport capacity and the observed partial repression of xylose utilization depends on the presence of intracellular glucose.


Subject(s)
Carbohydrate Metabolism , Escherichia coli/metabolism , Phosphotransferases/metabolism , Escherichia coli/enzymology , Escherichia coli/genetics , Escherichia coli/growth & development , Phenotype , Phosphotransferases/genetics
14.
Biotechnol Bioeng ; 73(6): 530-5, 2001 Jun 20.
Article in English | MEDLINE | ID: mdl-11344458

ABSTRACT

The effect of inactivation of the glucose phosphotransferase transport system (PTS) on 3-deoxy-D-arabino-heptulosonate 7-phosphate (DAHP) productivity and yield from glucose in Escherichia coli is reported. Strains used in this study were the PTS(+) PB103 and its PTS(-) glucose(+) derivative NF9. Their aroB(-) derivatives PB103B and NF9B were constructed to allow accurate measurement of total carbon flow into the aromatic pathway. The measured specific rates of DAHP synthesis were 0.55 and 0.94 mmol/g-dcw. h and the DAHP molar yields from glucose were 0.43 and 0.71 mol/mol for the PTS(+) aroB(-)and the PTS(-) glucose(+) aroB(-)strains, respectively. For the latter strain, this value represents 83% of the maximum theoretical yield for DAHP synthesis from glucose.


Subject(s)
Escherichia coli/metabolism , Glucose/metabolism , Sugar Phosphates/metabolism , Biological Transport , Escherichia coli/genetics , Mutation , Phosphoenolpyruvate Sugar Phosphotransferase System/genetics , Phosphoenolpyruvate Sugar Phosphotransferase System/metabolism , Phosphorylation
16.
Appl Microbiol Biotechnol ; 55(1): 69-75, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11234961

ABSTRACT

We evaluated the effect of several genetic factors reported as having a role in the induction of the expression of significant levels of recombinant protein in Bacillus subtilis. We utilized the beta-galactosidase reporter protein from Escherichia coli as our model for measuring the overproduction of heterologous proteins in B. subtilis. The lacZ gene was expressed in B. subtilis using the regulatory region of the subtilisin gene aprE. In this study, we considered factors known to modulate the transcription and translation initiation rates and genetic and mRNA stability. We also consider the effects of different genetic backgrounds, such as degU32 and hpr2, that until now have been studied independently. By changing the native -35 promoter box to the consensus TTGACA sequence of the aprE promoter, a significant 100-fold increase in the beta-galactosidase activity was obtained. On the other hand, changes such as the GTG to ATG start codon, the construction of a consensus AAGGAGG ribosome binding site, and the addition of the cryIIIA transcription terminator at the 3' end of the lacZ gene, produced only marginal effects on the final beta-galactosidase activity.


Subject(s)
Bacillus subtilis/genetics , Bacterial Proteins/metabolism , Biotechnology/methods , Gene Expression Regulation, Bacterial , Genetic Engineering , Membrane Transport Proteins , Bacillus subtilis/metabolism , Bacterial Proteins/genetics , Lac Operon/genetics , Lac Operon/physiology , Mutagenesis, Site-Directed , Promoter Regions, Genetic/genetics , Protein Biosynthesis , RNA Stability , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Transcription, Genetic , beta-Galactosidase/genetics , beta-Galactosidase/metabolism
17.
Rev. Hosp. Clin. Univ. Chile ; 12(3): 229-234, 2001.
Article in Spanish | LILACS | ID: lil-302625

ABSTRACT

Se analizan los múltiples factores que afectan la salud mental de las mujeres después de una histerectomía y se describe la experiencia clínica de la Unidad de Sexualidad Humana del Servicio de Ginecología del Hospital Clínico de la Universidad de Chile en talleres psicoeducativos interdisciplinarios


Subject(s)
Humans , Female , Hysterectomy , Self Concept , Comprehensive Health Care/methods , Physician-Patient Relations , Sexuality
18.
Arch. venez. farmacol. ter ; 20(1): 80-83, 2001. graf
Article in Spanish | LILACS | ID: lil-340962

ABSTRACT

Se realizó un estudio abierto, no controlado, multicéntrico, realizado con intención de tratar, en 60 pacientes con dorsolumbalgia mecánica, en el cual evaluó la efectividad y seguridad de nimesulide 100 mg dos veces al día, administrado durante 15 días. El tratamiento produjo un alivio significativo en los escores de dolor entre el día de inicio del tratamiento y los 5 días, con un alivio adicional importante entre los días 5 y 10, sin alivios adicionales para el día 15. El tiempo medio para la desaparición total del dolor fue de 8,5 días. La limitación funcional fue evaluada el día 0 y el día 15, obteniéndose una mejoría significativa desde el punto de vista estadístico. Se reportaron efectos adversos en 4 de los pacientes, de los cuales sólo uno ameritó la suspensión del tratamiento


Subject(s)
Humans , Male , Female , Anti-Inflammatory Agents, Non-Steroidal , Back , Low Back Pain/therapy , Venezuela
19.
Biochimie ; 82(9-10): 861-8, 2000.
Article in English | MEDLINE | ID: mdl-11086216

ABSTRACT

Most scorpion toxins are ligand peptides that recognize and bind to integral membrane proteins known as ion-channels. To date there are at least 202 distinct sequences described, obtained from 30 different species of scorpions, 27 from the family Buthidae and three from the family Scorpionidae. Toxins that recognize potassium and chloride channels are usually from 29 to 41 amino acids long, stabilized by three or four disulfide bridges, whereas those that recognize sodium channels are longer, 60 to 76 amino acid residues, compacted by four disulfide bridges. Toxins specific for calcium channels are scarcely known and have variable amino acid lengths. The entire repertoire of toxins, independently of their specificity, was analyzed together by computational programs and a phylogenetic tree was built showing two separate branches. The K(+) and Cl(-) channel specific toxins are clustered into 14 subfamilies, whereas those of Na(+) and Ca(2+) specific toxins comprise at least 12 subfamilies. There are clear similarities among them, both in terms of primary sequence and the main three-dimensional folding pattern. A dense core formed by a short alpha helix segment and several antiparallel beta-sheet stretches, maintained by disulfide pairing, seems to be a common structural feature present in all toxins. The physiological function of these peptides is manifested by a blockage of ion passage through the channels or by a modification of the gating mechanism that controls opening and closing of the ion pore.


Subject(s)
Ion Channels/drug effects , Peptides/pharmacology , Scorpion Venoms/pharmacology , Amino Acid Sequence , Animals , Molecular Sequence Data , Peptides/chemistry , Peptides/genetics , Phylogeny , Protein Folding , Protein Structure, Secondary , Protein Structure, Tertiary , Scorpion Venoms/chemistry , Scorpion Venoms/genetics , Sequence Homology, Amino Acid
20.
Microb Comp Genomics ; 5(1): 7-15, 2000.
Article in English | MEDLINE | ID: mdl-11011761

ABSTRACT

To study possible relationships between an organism's genomic DNA curvature and the aminoacid composition of its proteome, every peptidic sequence from fully determined genomes was retrotranslated using the E. coli codon preferences, and the curvature profiles of the resulting DNA sequences were calculated and compared. A clear interdependence between these two variables was observed, as each retrotranslated proteome presented a distinctive, statistically significant DNA curvature profile biased toward its natural DNA curvature profile. In addition, by comparing the profiles arising from real and randomly permuted proteomes, we also found a position-dependent contribution of the peptidic sequence to DNA curvature. The implications of these results support the idea of a possible selection toward a specific global curvature of genomes.


Subject(s)
Amino Acids/analysis , DNA/chemistry , Proteome/chemistry , Computational Biology , Genome , Nucleic Acid Conformation , Species Specificity
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