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1.
J Nutr Health Aging ; 15(3): 215-20, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21369670

RESUMEN

OBJECTIVE: To determine the impact of probiotics on the prevention of problems with bowel movements malnutrition and infection. DESIGN: A randomized, double-blind, placebo-controlled trial. SETTING: Peripheral Geriatric Hospital. PARTICIPANTS: 243 elderly patients age ≥ 65 y who were hospitalized in a Geriatric Orthopedic Rehabilitation Department. INTERVENTION: Participants were randomized into treatment or control groups (daily probiotics or placebo for 45 consecutive days, respectively). MEASUREMENTS: The main outcomes were: number of days of constipation or diarrhea and the number of days of laxative use. Secondary measures were nutritional status and blood measurements. RESULTS: Of 599 patients admitted to the Geriatric Rehabilitation ward, 345 were eligible and agreed to participate. During a 7-day pre-trial period, 102 patients dropped out (45 and 57 in the probiotic and placebo groups respectively). Out of the 243 patients who entered the study, 28 dropped out during the study (11.5%), leaving 215 patients. Throughout the 45 days of follow-up, the incidence of diarrhea was significantly lower among the study group (HR=0.42, p=0.04) with a more pronounced difference among participants aged ≥ 80 y (HR=0.32, p=0.026). Laxative use (as an indicator of constipation severity) was significantly lower in the study group compared with the control group (HR=0.74, p=0.032). Serum albumin, prealbumin and protein increased significantly more in the treatment group compared with the control group among participants age ≥ 80 y (P=0.047, p=0.07, p=0.03 respectively) but not in the younger age group. CONCLUSION: We showed that probiotic supplements may have a positive effect on bowel movements among orthopedic rehabilitation elderly patients.


Asunto(s)
Defecación/efectos de los fármacos , Control de Infecciones , Desnutrición/prevención & control , Probióticos/administración & dosificación , Factores de Edad , Anciano , Anciano de 80 o más Años , Estreñimiento/epidemiología , Estreñimiento/prevención & control , Diarrea/epidemiología , Diarrea/prevención & control , Método Doble Ciego , Femenino , Motilidad Gastrointestinal , Hospitalización , Humanos , Intestinos/microbiología , Masculino , Albúmina Sérica/metabolismo
2.
Proc Natl Acad Sci U S A ; 103(24): 9274-9, 2006 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-16754859

RESUMEN

Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) is a representative of the group of lactic acid-producing bacteria, mainly known for its worldwide application in yogurt production. The genome sequence of this bacterium has been determined and shows the signs of ongoing specialization, with a substantial number of pseudogenes and incomplete metabolic pathways and relatively few regulatory functions. Several unique features of the L. bulgaricus genome support the hypothesis that the genome is in a phase of rapid evolution. (i) Exceptionally high numbers of rRNA and tRNA genes with regard to genome size may indicate that the L. bulgaricus genome has known a recent phase of important size reduction, in agreement with the observed high frequency of gene inactivation and elimination; (ii) a much higher GC content at codon position 3 than expected on the basis of the overall GC content suggests that the composition of the genome is evolving toward a higher GC content; and (iii) the presence of a 47.5-kbp inverted repeat in the replication termination region, an extremely rare feature in bacterial genomes, may be interpreted as a transient stage in genome evolution. The results indicate the adaptation of L. bulgaricus from a plant-associated habitat to the stable protein and lactose-rich milk environment through the loss of superfluous functions and protocooperation with Streptococcus thermophilus.


Asunto(s)
Secuencia de Bases , Evolución Molecular , Genoma Bacteriano , Lactobacillus delbrueckii/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Metabolismo de los Hidratos de Carbono , Secuencias Repetitivas Esparcidas , Lactobacillus delbrueckii/metabolismo , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Streptococcus thermophilus/metabolismo , Sintenía , Yogur/microbiología
3.
Lupus ; 15(1): 32-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16482743

RESUMEN

The sense of coherence (SOC) construct refers to a global orientation, which significantly determines the link between stressors, coping with disease and health. The aim of this work was to assess possible associations between SOC and quality of life (QOL) scores among women with SLE. Sixty consecutive SLE women and 88 healthy women were included in the study. QOL was assessed using the SF-36 and the WHO QOL-Bref scales. The SOC has three main sub-scales: comprehensibility, manageability and meaningfulness. Regression analyses were used to study associations between various parameters of SF-36, WHO QOL-Bref, SOC, SLEDAI, indices of end organ damage (SDI), and demographic variables. Mean SLEDAI and SDI scores were 4.5 (SD = 5.6) and 1.29 (SD=2). SLE patients had significantly lower scores for all individual and summary sub-scales in the two QOL questionnaires compared with controls. SLE patients had significantly lower scores for the general, comprehensibility and meaningfulness sub-scales of SOC. No significant correlation was seen between SOC scores and measures of disease activity or end-organ damage. A strong linear correlation was seen between the scores of SOC, general WHO QOL-Bref, and the mental and physical component summary (MCS & PCS) scores of SF36. Age, SOC and SDI significantly affected the PCS score. SOC was the only variable independently associated with MCS. Education and SOC were significantly associated with the general WHO QOL-Bref. Age, education, SDI and SOC were independently associated with QOL of women with SLE.


Asunto(s)
Lupus Eritematoso Sistémico/psicología , Calidad de Vida , Adulto , Progresión de la Enfermedad , Femenino , Humanos , Pronóstico , Factores de Riesgo , Índice de Severidad de la Enfermedad , Perfil de Impacto de Enfermedad , Encuestas y Cuestionarios
4.
Public Health ; 119(5): 418-25, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15780332

RESUMEN

Fine particles are thought to pose a risk to health, especially for vulnerable groups such as children with asthma. These children are also known to be affected by meteorological and seasonal changes. We assessed the association between air pollution and lung function via peak expiratory flow (PEF), controlling for seasonal changes, meteorological conditions and personal physiological, clinical and sociodemographic measurements, in a panel of schoolchildren with asthma living near two power plants in Israel. Two hundred and eighty-five children with confirmed asthma performed PEF tests and completed a respiratory symptoms diary twice a day. Particulate matter <10 microm in diameter (PM10), particulate matter <2.5 microm in diameter (PM2.5) and meteorological conditions were measured at six fixed stations. Data were analysed using time series analysis-generalized linear model and generalized estimating equations. The models were built under the assumption that any health outcome belongs to a multivariate hierarchical system and depends on meteorological, geophysical and sociocultural variables and pollution factors. No significant differences were found in the demographic (age, gender, mean parental education level, parental smoking habits, place of birth and housing density), physiological (body mass index) and clinical factors (illness severity) between the communities participating in the study. A significant direct effect of PM2.5 on the PEF was found in Ashdod (P=0.000). In Sderot, this effect was through an interaction between PM10 and the sequential day of the year (P=0.000). The main conclusion of this study is that children with asthma are at risk from air pollution and geophysical conditions. Policy makers should take these results into consideration when setting thresholds for environmental protection.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Asma/fisiopatología , Centrales Eléctricas , Pruebas de Función Respiratoria , Tiempo (Meteorología) , Niño , Estudios de Cohortes , Humanos , Israel , Tamaño de la Partícula , Ápice del Flujo Espiratorio , Factores de Riesgo , Encuestas y Cuestionarios
5.
Appl Environ Microbiol ; 70(3): 1600-7, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15006784

RESUMEN

Lactococcus lactis, a food-grade nonpathogenic lactic acid bacterium, is a good candidate for the production of heterologous proteins of therapeutic interest. We examined host factors that affect secretion of heterologous proteins in L. lactis. Random insertional mutagenesis was performed with L. lactis strain MG1363 carrying a staphylococcal nuclease (Nuc) reporter cassette in its chromosome. This cassette encodes a fusion protein between the signal peptide of the Usp45 lactococcal protein and the mature moiety of a truncated form of Nuc (NucT). The Nuc secretion efficiency (secreted NucT versus total NucT) from this construct is low in L. lactis (approximately 40%). Twenty mutants affected in NucT production and/or in secretion capacity were selected and identified. In these mutants, several independent insertions mapped in the dltA gene (involved in D-alanine transfer in lipoteichoic acids) and resulted in a NucT secretion defect. Characterization of the dltA mutant phenotype with respect to NucT secretion revealed that it is involved in a late secretion stage by causing mature NucT entrapment at the cell surface.


Asunto(s)
Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Lipopolisacáridos/metabolismo , Ácidos Teicoicos/metabolismo , Alanina/metabolismo , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/genética , Genes Bacterianos , Lipopolisacáridos/química , Nucleasa Microcócica/biosíntesis , Nucleasa Microcócica/genética , Mutagénesis Insercional , Peptidoglicano/metabolismo , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Ácidos Teicoicos/química
6.
Am J Epidemiol ; 158(7): 695-704, 2003 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-14507606

RESUMEN

The objective of this study was to characterize longitudinal patterns of drug injection behavior for individuals and to identify their early determinants. Participants were 1,339 injection drug users recruited into the AIDS Link to Intravenous Experience (ALIVE) Study in Baltimore, Maryland, through community outreach efforts. The study was initiated in 1988, and follow-up continued through 2000, with semiannual visits. Patterns of self-reported drug injection (yes/no) were defined for each participant, based on the number of drug-use transitions. The effect of baseline factors was assessed using multinomial logistic regression models. Over the 12-year study period, four patterns were noted: 29% of participants remained persistent drug injectors, 20% ceased injection, 14% relapsed once, and 37% had multiple transitions. Persistent injectors had the shortest follow-up and the highest mortality. For persons who changed their behavior, 3.4 years elapsed before their first cessation attempt, on average. Factors differentiating the groups included history of incarceration, young age, participation in drug treatment programs, recent overdose, and commercial sex. The observed long-term injection patterns are consistent with the view of drug addiction as a chronic disease. This view emphasizes the need for prolonged efforts to sustain cessation and to prevent adverse health and social outcomes among injection drug users.


Asunto(s)
Abuso de Sustancias por Vía Intravenosa/epidemiología , Adulto , Distribución por Edad , Edad de Inicio , Consumo de Bebidas Alcohólicas/epidemiología , Baltimore/epidemiología , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Infecciones por VIH/epidemiología , Humanos , Estudios Longitudinales , Masculino , Oportunidad Relativa , Padres , Prevalencia , Prisioneros/estadística & datos numéricos , Recurrencia , Distribución por Sexo , Conducta Sexual/estadística & datos numéricos , Fumar/epidemiología , Factores Socioeconómicos , Abuso de Sustancias por Vía Intravenosa/psicología
7.
Clin Rheumatol ; 21(4): 280-3, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12189453

RESUMEN

The aim of the study was to assess the quality of life (QOL) and the psychological status of parents of children with juvenile chronic arthritis (JCA). The QOL, anxiety and depression of the parents of 28 children with JCA were evaluated and compared to those of the parents of 28 healthy children. Mothers of JCA children and mothers of healthy children reported similar QOL. The reported anxiety and depression levels were similar for mothers and fathers in both groups. The parents of children with pauciarticular-type JCA reported lower QOL and higher levels of anxiety and depression than the parents of children with other types, namely polyarticular and systemic JCA. These findings may be explained by the fact that the pauciarticular patients had shorter disease duration and were less frequently seen in the outpatient clinic. The QOL of mothers of children with JCA was found to be slightly impaired in the group of children with pauciarticular JCA. Future larger studies are needed to confirm these results, as the number of subjects in the three groups was rather low.


Asunto(s)
Artritis Juvenil/psicología , Salud de la Familia , Padres/psicología , Calidad de Vida/psicología , Perfil de Impacto de Enfermedad , Adulto , Artritis Juvenil/fisiopatología , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad
8.
Arch Environ Health ; 56(4): 320-6, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11572275

RESUMEN

The authors evaluated the possible association between dietary history and plasma clastogenic factors in children who immigrated to Israel between 1989 and 1993 from regions contaminated by the Chernobyl accident. The authors compared questionnaire data about demographic variables, dietary histories before and after immigration occurred, and health status with clastogenic factor scores for 162 immigrants. Logistic regression analysis revealed a negative association between clastogenic factor scores and frequency of consumption of fresh vegetables and fruit among children < or = 7 yr of age during the postimmigration period. Intake of eggs and fish by boys who were < or = 7 yr of age prior to immigration was associated positively with clastogenic factor scores. Consumption of fresh vegetables and fruits afforded protection to the immune systems of children who were < or = 7 yr of age.


Asunto(s)
Antioxidantes/administración & dosificación , Protección a la Infancia/estadística & datos numéricos , Dieta/efectos adversos , Dieta/estadística & datos numéricos , Emigración e Inmigración/estadística & datos numéricos , Exposición a Riesgos Ambientales/efectos adversos , Mutágenos/efectos adversos , Mutágenos/metabolismo , Liberación de Radiactividad Peligrosa/estadística & datos numéricos , Adolescente , Distribución por Edad , Factores de Edad , Análisis de Varianza , Niño , Preescolar , Encuestas sobre Dietas , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente , Femenino , Frutas , Humanos , Lactante , Israel , Modelos Logísticos , Masculino , Características de la Residencia/estadística & datos numéricos , Factores de Riesgo , Distribución por Sexo , Encuestas y Cuestionarios , U.R.S.S./etnología , Verduras
9.
Arch Microbiol ; 175(5): 334-43, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11409543

RESUMEN

The genes encoding a binding-protein-dependent ABC transporter for dipeptides (Dpp) were identified in Lactococcus lactis subsp. cremoris MG1363. Two (dppA and dppP) of the six ORFs (dppAdppPBCDF) encode proteins that are homologous to peptide- and pheromone-binding proteins. The dppP gene contains a chain-terminating nonsense mutation and a frame-shift that may impair its function. The functionality of the dpp genes was proven by the construction of disruption mutants via homologous recombination. The expression of DppA and various other components of the proteolytic system was studied in synthetic and peptide-rich media and by using isogenic peptide-transport mutants that are defective in one or more systems (Opp, DtpT, and/or Dpp). In peptide-rich medium, DppA was maximally expressed in mutants lacking Opp and DtpT. DppA expression also depended on the growth phase and was repressed by tri-leucine and tri-valine. The effect of tri-leucine on DppA expression was abolished when leucine was present in the medium. Importantly, the Dpp system also regulated the expression of other components of the proteolytic system. This regulation was achieved via the internalization of di-valine, which caused a 30-50% inhibition in the expression of the proteinase PrtP and the peptidases PepN and PepC. Similar to the regulation of DppA, the repressing effect was no longer observed when high concentrations of valine were present. The intricate regulation of the components of the proteolytic system by peptides and amino acids is discussed in the light of the new and published data.


Asunto(s)
Proteínas Portadoras/metabolismo , Dipéptidos/metabolismo , Proteínas de Escherichia coli , Genes Bacterianos/genética , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Proteínas de Unión Periplasmáticas , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Portadoras/genética , Endopeptidasas/metabolismo , Expresión Génica , Lactococcus lactis/crecimiento & desarrollo , Datos de Secuencia Molecular , Oligopéptidos/metabolismo , Transporte de Proteínas , Especificidad por Sustrato
10.
Genome Res ; 11(5): 731-53, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11337471

RESUMEN

Lactococcus lactis is a nonpathogenic AT-rich gram-positive bacterium closely related to the genus Streptococcus and is the most commonly used cheese starter. It is also the best-characterized lactic acid bacterium. We sequenced the genome of the laboratory strain IL1403, using a novel two-step strategy that comprises diagnostic sequencing of the entire genome and a shotgun polishing step. The genome contains 2,365,589 base pairs and encodes 2310 proteins, including 293 protein-coding genes belonging to six prophages and 43 insertion sequence (IS) elements. Nonrandom distribution of IS elements indicates that the chromosome of the sequenced strain may be a product of recent recombination between two closely related genomes. A complete set of late competence genes is present, indicating the ability of L. lactis to undergo DNA transformation. Genomic sequence revealed new possibilities for fermentation pathways and for aerobic respiration. It also indicated a horizontal transfer of genetic information from Lactococcus to gram-negative enteric bacteria of Salmonella-Escherichia group.


Asunto(s)
Genoma Bacteriano , Lactococcus lactis/genética , Aminoácidos/biosíntesis , Aminoácidos/genética , Aminoácidos/metabolismo , Proteínas Bacterianas/metabolismo , Bacteriófagos/genética , Transporte Biológico Activo/genética , Pared Celular/genética , Pared Celular/metabolismo , Elementos Transponibles de ADN/genética , Endopeptidasas/genética , Metabolismo Energético/genética , Enterobacteriaceae/genética , Regulación de la Expresión Génica/genética , Transferencia de Gen Horizontal/genética , Ácido Láctico/metabolismo , Lactococcus lactis/aislamiento & purificación , Lactococcus lactis/metabolismo , Lactococcus lactis/virología , Datos de Secuencia Molecular , Familia de Multigenes/genética , Nucleótidos/biosíntesis , Nucleótidos/genética , Sistemas de Lectura Abierta/genética , Provirus/genética , ARN Bacteriano/genética , Análisis de Secuencia de ADN/métodos , Transducción de Señal/genética , Transformación Genética/genética , Vitaminas/biosíntesis , Vitaminas/genética
11.
Clin Rheumatol ; 20(1): 15-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11254234

RESUMEN

Fibromyalgia (FS) is an idiopathic chronic pain syndrome defined by widespread non-articular musculoskeletal pain and generalised tender points. As there is no effective treatment, patients with this condition have impaired quality of life (QoL). The aim of this study was to assess the possible effect of balneotherapy at the Dead Sea area on the QoL of patients with FS. Forty-eight subjects participated in the study; half of them received balneotherapy, and half did not. Their QoL (using SF-36), psychological well-being and FS-related symptoms were assessed prior to arrival at the spa hotel in the Dead Sea area, at the end of the 10-day stay, and 1 and 3 months later. A significant improvement was reported on most subscales of the SF-36 and on most symptoms. The improvement in physical aspects of QoL lasted usually 3 months, but on psychological measures the improvement was shorter. Subjects in the balneotherapy group reported higher and longer-lasting improvement than subjects in the control group. In conclusion, staying at the Dead Sea spa, in addition to balneotherapy, can transiently improve the QoL of patients with FS. Other studies with longer follow-up are needed to support our findings.


Asunto(s)
Balneología , Fibromialgia/psicología , Fibromialgia/terapia , Calidad de Vida/psicología , Femenino , Fibromialgia/epidemiología , Humanos , Israel/epidemiología , Persona de Mediana Edad , Distribución Aleatoria , Factores de Tiempo
12.
Nucleic Acids Res ; 29(3): 644-51, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11160885

RESUMEN

We report the genetic organisation of six prophages present in the genome of Lactococcus lactis IL1403. The three larger prophages (36-42 kb), belong to the already described P335 group of temperate phages, whereas the three smaller ones (13-15 kb) are most probably satellites relying on helper phage(s) for multiplication. These data give a new insight into the genetic structure of lactococcal phage populations. P335 temperate phages have variable genomes, sharing homology over only 10-33% of their length. In contrast, virulent phages have highly similar genomes sharing homology over >90% of their length. Further analysis of genetic structure in all known groups of phages active on other bacterial hosts such as Escherichia coli, Bacillus subtilis, MYCOBACTERIUM: and Streptococcus thermophilus confirmed the existence of two types of genetic structure related to the phage way of life. This might reflect different intensities of horizontal DNA exchange: low among purely virulent phages and high among temperate phages and their lytic homologues. We suggest that the constraints on genetic exchange among purely virulent phages reflect their optimal genetic organisation, adapted to a more specialised and extreme form of parasitism than temperate/lytic phages.


Asunto(s)
Bacteriófagos/genética , Lactococcus lactis/virología , ADN Bacteriano/genética , ADN Viral/química , ADN Viral/genética , Orden Génico , Genes Virales/genética , Genoma Bacteriano , Genoma Viral , Lactococcus lactis/genética , Lisogenia , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Análisis de Secuencia de ADN
13.
Clin Rheumatol ; 19(4): 265-9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10941805

RESUMEN

Assessment of health status in patients with rheumatic disease, including fibromyalgia (FM), using structured questionnaires has become an important approach to evaluate treatment and outcome. The objectives of this study were to validate a translated version of the Clinical Health Assessment Questionnaire (CLINHAQ) to be used by Hebrew-speaking populations, and specifically to evaluate its usefulness in fibromyalgia syndrome (FM). The CLINHAQ was translated into Hebrew and administered to 90 women with FM along with the Hebrew versions of the Fibromyalgia Impact Questionnaire (FIQ) and the Quality of Life (QOL) Scale. The CLINHAQ includes scales of functional disability, helplessness, anxiety and depression, as well as assessment of current health status and satisfaction with this. All subjects were asked about the presence and severity (assessed by visual analogue scale) of current FM symptoms (pain, fatigue, anxiety etc.); a count of 18 tender points was conducted by thumb palpation, and tenderness thresholds were measured by dolorimetry. Test-retest reliability was assessed by Pearson correlation coefficients, and internal consistency was evaluated with Cronbach's alpha coefficient of reliability. Construct validity was tested by correlating the CLINHAQ items with measures of symptom severity, count of tender point, tenderness thresholds, physical functioning measured by FIQ, and with a score of QOL. Test-retest reliability coefficients ranged from 0.82 to 0.99, and Cronbach's alpha coefficients from 0.725 to 0.929. Significant moderate to high correlations were obtained between most subscales of CLINHAQ and measures of physical functioning, quality of life and severity of FM symptoms. In conclusion, the CLINHAQ is a reliable and valid instrument for measuring health status and physical functioning in Israeli women with FM.


Asunto(s)
Fibromialgia , Estado de Salud , Calidad de Vida , Encuestas y Cuestionarios , Adulto , Interpretación Estadística de Datos , Femenino , Fibromialgia/diagnóstico , Fibromialgia/fisiopatología , Humanos , Israel , Persona de Mediana Edad , Dimensión del Dolor
14.
Genes Cells ; 5(6): 453-61, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10886371

RESUMEN

BACKGROUND: In Escherichia coli, the Chi sequence modulates the activity of RecBCD, a powerful double-stranded (ds) DNA exonuclease/helicase. Chi attenuates RecBCD exonuclease activity and stimulates homologous recombination in an orientation-dependent manner. ChiEc is frequent and over-represented on its genome, which is thought to be related to its role in dsDNA break repair. We previously identified a Chi-like sequence (referred to as ChiLl) and an exonuclease/helicase in the Gram-positive bacterium Lactococcus lactis. ChiLl and RexAB are functional analogues of ChiEc and RecBCD. RESULTS: We report that ChiLl attenuates RexAB exonuclease activity and stimulates homologous recombination in an orientation-dependent manner. Analysis of ChiLl distribution on the L. lactis chromosome reveals that ChiLl is frequent, highly over-represented, and oriented with respect to the direction of replication. CONCLUSION: Our results show that a single orientation of ChiLl interacts with RexAB. The active orientation is preferentially found on the replication leading strand of the L. lactis genome, consistent with a primary role of ChiLl in repair of dsDNA breaks at the replication fork. We propose that orientation-dependence of Chi activity and over-representation of Chi sequences on bacterial genomes may be conserved properties of exonuclease/helicase-Chi couples. Other properties of the Chi sequence distribution on the genomes might reflect more specific characteristics of each couple and of the host.


Asunto(s)
Exodesoxirribonucleasas/genética , Exodesoxirribonucleasas/metabolismo , Lactococcus lactis/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Inversión Cromosómica , Cromosomas Bacterianos/genética , Replicación del ADN , Exodesoxirribonucleasa V , Frecuencia de los Genes , Lactococcus lactis/metabolismo , Recombinación Genética
15.
Mol Microbiol ; 35(5): 1042-51, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10712686

RESUMEN

We identified an exported protease in Lactococcus lactis ssp. lactis strain IL1403 belonging to the HtrA/DegP family. Inactivation of the chromosomal gene (htrALl) encoding this protease (HtrALl) results in growth thermo-sensitivity at very high temperatures (above 37 degrees C for L. lactis). The role of htrALl in extracellular proteolysis under normal growth conditions was examined by testing the stability of different exported proteins (i.e. fusions, a heterologous pre-pro-protein or a native protein containing repeats), having different locations. In the wild-type (wt) strain, degradation products, including the C-terminal protein ends, were present in the medium, indicating that proteolysis occurs during or after export to the cell surface; in one case, degradation was nearly total. In contrast, proteolysis was totally abolished in the htrA strain for all five proteins tested, and the yield of full-length products was significantly increased. These results suggest that HtrALl is the sole extracellular protease that degrades abnormal exported proteins. In addition, our results reveal that HtrALl is needed for the pro-peptide processing of a natural pro-protein and for maturation of a native protein. We propose that in lactococci, and possibly in other Gram-positive organisms with small sized-genomes, a single surface protease, HtrA, is totally responsible for the housekeeping of exported proteins.


Asunto(s)
Proteínas Bacterianas/metabolismo , Proteínas de Choque Térmico , Lactococcus lactis/enzimología , Proteínas Periplasmáticas , Procesamiento Proteico-Postraduccional , Serina Endopeptidasas/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Cartilla de ADN , Datos de Secuencia Molecular , Muramidasa/metabolismo , Pliegue de Proteína , Proteínas Recombinantes de Fusión/metabolismo
16.
Clin Exp Rheumatol ; 18(1): 103-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10728454

RESUMEN

OBJECTIVE: The aim of the present study was to assess the quality of life (QOL) and the psychological status of parents of children with familial Mediterranean fever (FMF). METHODS: The QOL, anxiety and depression of the parents of 35 children with FMF were evaluated and compared to the parents of 23 healthy children. RESULTS: Mothers of FMF children had lower QOL scores than mothers of healthy children: 5.5 +/- 1.1 versus 6.0 +/- 0.6 (p = 0.048). They also expressed higher levels of anxiety and depression. Within each group, mothers were more anxious and depressed than fathers. Parents with several FMF children were not significantly different from parents with only one FMF child. CONCLUSION: The QOL and psychological well being of parents with FMF children were found to be slightly impaired, especially that of the mothers.


Asunto(s)
Fiebre Mediterránea Familiar , Padre/psicología , Madres/psicología , Calidad de Vida , Adolescente , Ansiedad/psicología , Niño , Depresión/psicología , Femenino , Humanos , Masculino , Valores de Referencia
17.
Appl Environ Microbiol ; 66(2): 571-7, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10653720

RESUMEN

In Lactococcus lactis, which is widely used as a starter in the cheese industry, the first step of aromatic and branched-chain amino acid degradation is a transamination which is catalyzed by two major aminotransferases. We have previously purified and characterized biochemically and genetically the aromatic aminotransferase, AraT. In the present study, we purified and studied the second enzyme, the branched-chain aminotransferase, BcaT. We cloned and sequenced the corresponding gene and used a mutant, along with the luciferase gene as the reporter, to study the role of the enzyme in amino acid metabolism and to reveal the regulation of gene transcription. BcaT catalyzes transamination of the three branched-chain amino acids and methionine and belongs to class IV of the pyridoxal 5'-phosphate-dependent aminotransferases. In contrast to most of the previously described bacterial BcaTs, which are hexameric, this enzyme is homodimeric. It is responsible for 90% of the total isoleucine and valine aminotransferase activity of the cell and for 50 and 40% of the activity towards leucine and methionine, respectively. The original role of BcaT was probably biosynthetic since expression of its gene was repressed by free amino acids and especially by isoleucine. However, in dairy strains, which are auxotrophic for branched-chain amino acids, BcaT functions only as a catabolic enzyme that initiates the conversion of major aroma precursors. Since this enzyme is still active under cheese-ripening conditions, it certainly plays a major role in cheese flavor development.


Asunto(s)
Aminoácidos de Cadena Ramificada/metabolismo , Lactococcus lactis/enzimología , Transaminasas/metabolismo , Clonación Molecular , Medios de Cultivo , Regulación Bacteriana de la Expresión Génica , Lactococcus lactis/genética , Lactococcus lactis/crecimiento & desarrollo , Datos de Secuencia Molecular , Peso Molecular , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Transaminasas/química , Transaminasas/genética , Transaminasas/aislamiento & purificación , Transcripción Genética
18.
J Bacteriol ; 181(20): 6238-46, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10515910

RESUMEN

The cytoplasmic accumulation of exogenous betaine stimulates the growth of Lactococcus lactis cultivated under hyperosmotic conditions. We report that L. lactis possesses a single betaine transport system that belongs to the ATP-binding cassette (ABC) superfamily of transporters. Through transposon mutagenesis, a mutant deficient in betaine transport was isolated. We identified two genes, busAA and busAB, grouped in an operon, busA (betaine uptake system). The transcription of busA is strongly regulated by the external osmolality of the medium. The busAA gene codes for the ATP-binding protein. busAB encodes a 573-residue polypeptide which presents two striking features: (i) a fusion between the regions encoding the transmembrane domain (TMD) and the substrate-binding domain (SBD) and (ii) a swapping of the SBD subdomains when compared to the Bacillus subtilis betaine-binding protein, OpuAC. BusA of L. lactis displays a high affinity towards betaine (K(m) = 1.7 microM) and is an osmosensor whose activity is tightly regulated by external osmolality, leading the betaine uptake capacity of L. lactis to be under dual control at the biochemical and genetic levels. A protein presenting the characteristics predicted for BusAB was detected in the membrane fraction of L. lactis. The fusion between the TMD and the SBD is the first example of a new organization within prokaryotic ABC transporters.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Adenosina Trifosfatasas , Proteínas Bacterianas/metabolismo , Betaína/metabolismo , Genes Bacterianos , Lactococcus lactis/metabolismo , Transportadoras de Casetes de Unión a ATP/genética , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Transporte Biológico , Fraccionamiento Celular , Regulación Bacteriana de la Expresión Génica , Lactococcus lactis/genética , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Presión Osmótica , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
19.
Antonie Van Leeuwenhoek ; 76(1-4): 27-76, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10532372

RESUMEN

Lactococcus lactis is an AT-rich gram positive bacterium phylogenetically close to the genus Streptococcus. Various strains of L. lactis are used in dairy industry as starters for cheese making. L. lactis is also one of the well characterized laboratory microorganisms, widely used for studies on physiology of lactic acid bacteria. We describe here a low redundancy sequence of the genome of the strain L. lactis IL1403. The strategy which we followed to determine the sequence consists of two main steps. First, a limited number of plasmids and lambda-phages that carry random segments of the genome were sequenced. Second, sequences of the inserts were used for production of novel sequencing templates by applying Multiplex Long Accurate PCR protocols. Using of these PCR products allowed to determine the sequence of the entire 2.35 Mb genome with a very low redundancy, close to 2. The error rate of the sequence is estimated to be below 1%. The correctness of the sequence assembly was confirmed by PCR amplification of the entire L. lactis IL1403 genome, using a set of 266 oligonucleotides. Anotation of the sequence was undertaken by using automatic gene prediction computer tools. This allowed to identify 1495 protein-encoding genes, to locate them on the genome map and to classify their functions on the basis of homology to known proteins. The function of about 700 genes expected to encode proteins that lack homologs in data bases cannot be reliably predicted in this way. The approach which we used eliminates high redundancy sequencing and mapping efforts, needed to obtain detailed and comprehensive genetic and physical maps of a bacterium. Availability of detailed genetic and physical maps of the L. lactis IL1403 genome provides many entries to study metabolism and physiology of bacteria from this group. The presence of 42 copies of five different IS elements in the IL1403 genome confirms the importance of these elements for genetic exchange in Lactococci. These include two previously unknown elements, present at seven and fifteen copies and designated IS1077 and IS983, respectively. Five potential or rudimentary prophages were identified in the genome by detecting clusters of phage-related genes. The metabolic and regulatory potential of L. lactis was evaluated by inspecting gene sets classified into different functional categories. L. lactis has the genetic potential to synthesise 20 standard amino acids, purine and pyrimidine nucleotides and at least four cofactors. Some of these metabolites, which are usually present in chemically defined media, can probably be omitted. About twenty compounds can be used by L. lactis as a sole carbon source. Some 83 regulators were revealed, indicating a regulatory potential close to that of Haemophilus influenzae, a bacterium with a similar genome size. Unexpectedly, L. lactis has a complete set of late competence genes, which may have concerted transcriptional regulation and unleadered polycistronic mRNAs. These findings open new possibilities for developing genetic tools, useful for studies of gene regulation in AT-rich gram positive bacteria and for engineering of new strains for the diary industry.


Asunto(s)
Genoma Bacteriano , Lactobacillus/genética , Proteínas Bacterianas/genética , Bacteriófagos/genética , Secuencia de Bases , Mapeo Cromosómico , Datos de Secuencia Molecular , Plásmidos
20.
J Rheumatol ; 26(8): 1816-21, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10451082

RESUMEN

OBJECTIVE: To validate a translated version of the revised and expanded Arthritis Impact Measurement Scales (AIMS2) to be used by Hebrew speaking populations. METHODS: The AIMS2 was translated into Hebrew and administered to 66 women with fibromyalgia (FM) along with the Hebrew versions of the Fibromyalgia Impact Questionnaire (FIQ) and the Quality of Life (QOL) Scale. All subjects were asked about the presence and severity (assessed by visual analog scale) of FM symptoms (pain, fatigue, anxiety, etc.); a count of 18 tender points was conducted by thumb palpation, and tenderness thresholds were measured by dolorimetry. Test-retest reliability was assessed by Pearson correlation coefficients, and internal consistency was evaluated with Cronbach's alpha coefficient of reliability. Construct validity was tested by correlating the AIMS2 items with measures of symptom severity, count of tender points, tenderness thresholds, physical functioning measured by FIQ, and with a score of QOL. RESULTS: Test-retest reliability coefficients ranged from 0.84 to 0.99, and Cronbach's alpha coefficients from 0.74 to 0.93. Significant moderate to high correlations were obtained between the AIMS2 subscales (except self-care) and measures of physical functioning, quality of life, severity of FM symptoms, and number of tender points. CONCLUSION: The AIMS2 is a reliable and valid instrument for measuring health status and physical functioning in Israeli women with FM.


Asunto(s)
Fibromialgia/fisiopatología , Lenguaje , Perfil de Impacto de Enfermedad , Estudios de Evaluación como Asunto , Femenino , Fibromialgia/etnología , Fibromialgia/psicología , Estado de Salud , Encuestas Epidemiológicas , Humanos , Judíos , Persona de Mediana Edad , Reproducibilidad de los Resultados
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