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1.
Support Care Cancer ; 29(7): 3643-3648, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33179136

RESUMEN

INTRODUCTION: Pain is a serious adverse event which frequently accompanies hematopoietic stem cell transplantation (HSCT). The safety and efficacy of NSAIDS during HSCT is currently unknown. Salsalate is a platelet-sparing NSAID with a favorable toxicity profile compared with other NSAIDS. We report the safety and efficacy of salsalate for different types of pain during SCT. METHODS: We conducted a retrospective study of SCT recipients empirically treated with salsalate for > 48 h. Pain scores were assessed using the verbal rating scale for pain. A subset analysis of patients who received > 7 days of salsalate during periods of pancytopenia, mucositis, and other end-organ toxicities is included. RESULTS: Sixty-four patients, 42 auto- and 22 allografts, were identified. Reason for use: vertebral-related pain (30%), musculoskeletal (30%), and cytokine inflammatory pain syndromes (24%). Median dose 1500 mg/day, number of treatment days = 5, started on day+5 post-HSCT. Pain resolved/improved to pain score < 4 in 76% and stable in 15%. Forty-four patients (28-auto and 16 allografts) received > 7-day salsalate. Median WBC and platelet nadir were < 0.1 and 10,000 cells/ml respectively. EFFICACY: pain was improved or eradicated in 64% and stable in 32%. TOXICITY: LFT elevation (n = 2), elevated serum creatinine (n = 2), and minor bleed (n = 5-nose, gums, and urine). Salsalate discontinuation (n = 6): ineffective (n = 1), the liver (n = 1), the kidney (n = 1), > 5 platelet transfusions (n = 1), and vomiting (n = 2). There was no treatment related mortality. Salsalate was well tolerated, safe, and beneficial for several different types of pain during HSCT.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Mucositis/tratamiento farmacológico , Salicilatos/uso terapéutico , Acondicionamiento Pretrasplante/efectos adversos , Trasplante Homólogo/efectos adversos , Adulto , Anciano , Antiinflamatorios no Esteroideos/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor , Estudios Retrospectivos , Salicilatos/farmacología , Adulto Joven
2.
Gene Ther ; 16(1): 10-6, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18633446

RESUMEN

Vascular endothelial growth factor (VEGF) is important in pathological neovascularization, which is a key component of diseases such as the wet form of age-related macular degeneration, proliferative diabetic retinopathy and cancer. One of the most potent naturally occurring VEGF binders is VEGF receptor Flt-1. We have generated two novel chimeric VEGF-binding molecules, sFLT01 and sFLT02, which consist of the second immunoglobulin (IgG)-like domain of Flt-1 fused either to a human IgG1 Fc or solely to the CH3 domain of IgG1 Fc through a polyglycine linker 9Gly. In vitro analysis showed that these novel molecules are high-affinity VEGF binders. We have demonstrated that adeno-associated virus serotype 2 (AAV2)-mediated intravitreal gene delivery of sFLT01 efficiently inhibits angiogenesis in the mouse oxygen-induced retinopathy model. There were no histological observations of toxicity upon persistent ocular expression of sFLT01 for up to 12 months following intravitreal AAV2-based delivery in the rodent eye. Our data suggest that AAV2-mediated intravitreal gene delivery of our novel molecules may be a safe and effective treatment for retinal neovascularization.


Asunto(s)
Terapia Genética/métodos , Proteínas Recombinantes de Fusión/genética , Retina/metabolismo , Neovascularización Retiniana/terapia , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Dependovirus/genética , Técnica del Anticuerpo Fluorescente , Expresión Génica , Ingeniería Genética , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Humanos , Fragmentos Fc de Inmunoglobulinas/genética , Ratones , Ratones Endogámicos C57BL , Unión Proteica , Estructura Terciaria de Proteína , ARN Mensajero/análisis , Proteínas Recombinantes de Fusión/metabolismo , Neovascularización Retiniana/metabolismo , Transducción Genética/métodos , Transgenes , Receptor 1 de Factores de Crecimiento Endotelial Vascular/genética
3.
Infect Disord Drug Targets ; 7(2): 169-81, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17970227

RESUMEN

Mycobacterium tuberculosis (Mtb) remains the deadliest bacterial pathogen worldwide, causing an estimated 1.7 million deaths in 2004 among an infected population of approximately 2 billion people, according to the World Health Organization (WHO). Therapeutic options are limited to a few drugs that are becoming increasingly ineffective. Multidrug-resistant (MDR) Mtb strains are prevalent globally, fueled by inadequate patient compliance of drug intake. Recently, a high incidence of extensively drug-resistant (XDR) strains resistant to all currently used drugs was reported among patients with the human immunodeficiency virus (HIV) in KwaZulu Natal, South Africa [1]. The high mortality rate and short survival time of patients with XDR Mtb was especially alarming. The emergence of XDR mycobacteria emphasizes the urgent need for the identification of novel targets and development of new drugs. New potential drug targets exist in the Mtb respiratory chain. Certain classes of drugs have long been shown to exert significant tuberculocidal activity, such as the phenothiazines [2, 3]. Phenothiazines inhibit one of the key enzymes of the respiratory chain; type II NADH:menaquinone oxidoreductase or NDH-2 [4]. The effectiveness of this class of drugs against Mtb justifies further research into the respiratory chain, with the aim of elucidating its physiologic roles in in vitro and in vivo survival, and discovering new (sub)classes of drugs that can safely serve as inhibitors for clinical use. In this chapter, we critically review the recent advances in this field, with particular emphasis on NDH-2, and underscore the kinds of research further needed for drug development.


Asunto(s)
Antituberculosos/farmacología , Inhibidores Enzimáticos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/enzimología , Quinona Reductasas/antagonistas & inhibidores , Farmacorresistencia Bacteriana , Transporte de Electrón/efectos de los fármacos , Etionamida/farmacología , Isoniazida/farmacología , Mycobacterium tuberculosis/genética , Fenotiazinas/farmacología
4.
IET Syst Biol ; 1(2): 130-48, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17441554

RESUMEN

We propose an abstraction method for medium-scale biomolecular networks, based on hybrid dynamical systems with continuous multi-affine dynamics. This abstraction method follows naturally from the notion of approximating nonlinear rate laws with continuous piecewise linear functions and can be easily automated. An efficient reachability algorithm is possible for the resulting class of hybrid systems. An efficient reachability algorithm is possible for the resulting class of hybrid systems. An approximation for an ordinary differential equation model of the lac operon is constructed, and it is shown that the abstraction passes the same experimental tests as were used to validate the original model. The well studied biological system exhibits bistability and switching behaviour, arising from positive feedback in the expression mechanism of the lac operon. The switching property of the lac system is an example of the major qualitative features that are the building blocks of higher level, more coarse-grained descriptions. The present approach is useful in helping to correctly identify such properties and in connecting them to the underlying molecular dynamical details. Reachability analysis together with the knowledge of the steady-state structure are used to identify ranges of parameter values for which the system maintains the bistable switching property.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Regulación de la Expresión Génica/genética , Operón Lac/genética , Lactosa/metabolismo , Modelos Biológicos , Transducción de Señal/genética , Algoritmos , Simulación por Computador , Proteínas de Escherichia coli/genética , Lactosa/genética
5.
Phys Rev Lett ; 96(24): 242001, 2006 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-16907231

RESUMEN

The asymmetry in the rho angular distribution in the sequential decay Omega+-->LamdaKappa+-->rhopi+Kappa+. has been measured to be alphaOmegaalphaLamda=[+1.16+/-0.18(stat)+/-0.17(syst)]x10(-2) using 1.89x10(6) unpolarized Omega+ decays recorded by the HyperCP (E871) experiment at Fermilab. Using the known value of alphaLamda, and assuming that alphaLamda=-alphaLamda, alphaOmega=[-1.81+/-0.28(stat)+/-0.26(syst)]x10(-2). A comparison between this measurement of alphaOmegaalphaLamda and recent measurements of alphaOmegaalphaLamda made by HyperCP shows no evidence of a violation of CP symmetry.

6.
Cell Mol Biol (Noisy-le-grand) ; 51(7): 599-606, 2005 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-16359610

RESUMEN

Walter Elsasser was an eminent theoretical physicist who devoted much of his spare time for over half a century (approximately 1935-1987) to the development of a holistic theory of organisms. The three basic principles of his biological theory are a) order in the large which dominates heterogeneity in the small; b) creative selection of the relatively small number of cells and organisms in nature as compared with the immense number of potential molecular states allowed by quantum mechanics, based on the number of atoms, molecules and chemical bonds in a cell, and c) holistic memory in reproduction of cells and organisms, a process which is supplementary to, and fundamentally different in type from the information stored in DNA. His ideas have either been coolly received or ignored by biologists, at least partly because of their purely formal character, although that is considered the sine qua non for theories in physical science. I cite a variety of experiments at the cellular level that illustrate his principles. Those experiments add a concrete dimension to his abstractions that hopefully will promote a dialog between theory and practice to facilitate development of a non-reductionist biology.


Asunto(s)
Biología/historia , Modelos Biológicos , Animales , Procesos de Crecimiento Celular , Crecimiento y Desarrollo , Historia del Siglo XX , Humanos , Teoría Cuántica , Estados Unidos
7.
Phys Rev Lett ; 94(18): 181801, 2005 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-15904358

RESUMEN

A sensitive search for the lepton-number-violating decay Xi(-)-->pmu(-)mu(-) has been performed using a sample of approximately 10(9) Xi(-) hyperons produced in 800 GeV/c p-Cu collisions. We obtain B(Xi(-)-->pmu(-)mu(-))<4.0x10(-8) at 90% confidence, improving on the best previous limit by 4 orders of magnitude.

8.
Phys Rev Lett ; 94(10): 101804, 2005 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-15783474

RESUMEN

A sensitive search for the rare decays Omega(-)--> Lambdapi(-) and Xi(0)--> ppi(-) has been performed using data from the 1997 run of the HyperCP (Fermilab E871) experiment. Limits on other such processes do not exclude the possibility of observable rates for |DeltaS| = 2 nonleptonic hyperon decays, provided the decays occur through parity-odd operators. We obtain the branching-fraction limits B(Omega(-)-->Lambdapi(-)) < 2.9 x 10(-6) and B(Xi(0)--> ppi(-)) < 8.2 x 10(-6), both at 90% confidence level.

9.
Phys Rev Lett ; 94(2): 021801, 2005 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-15698162

RESUMEN

We report the first evidence for the decay Sigma(+)-->pmu(+)mu(-) from data taken by the HyperCP (E871) experiment at Fermilab. Based on three observed events, the branching ratio is B(Sigma(+)-->pmu(+)mu(-))=[8.6(+6.6)(-5.4)(stat)+/-5.5(syst)]x10(-8). The narrow range of dimuon masses may indicate that the decay proceeds via a neutral intermediate state, Sigma(+)-->pP(0),P0-->mu(+)mu(-) with a P0 mass of 214.3+/-0.5 MeV/c(2) and branching ratio B(Sigma(+)-->pP(0),P0-->mu(+)mu(-))=[3.1(+2.4)(-1.9)(stat)+/-1.5(syst)]x10(-8).

10.
Magnes Res ; 18(4): 268-74, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16548142

RESUMEN

The proliferation of cells in culture requires the presence of growth factors in the medium, provided either by serum or purified proteins. Cells are made quiescent by contact inhibition and sharply diminishing the concentration of growth factors overnight; they are then stimulated by restoring the original high concentration of the growth factors. The addition activates a coordinated group of biochemical responses within minutes, that is followed in 5-12 hr by the onset of DNA synthesis and then mitosis. The most critical of the early responses for the later onset of DNA synthesis is an increase in the rate of protein synthesis, which must be maintained by the continued presence of the growth factors throughout the G1 period. Lowering the Mg2+ concentration of the medium and therefore within the cells, reduces all the early reactions of the coordinate response including protein synthesis, which is followed by a disproportionately large reduction in the rate of DNA synthesis. Stimulation in the presence of physiological concentration of Mg2+ raises the total Mg and the free Mg2+ of the cells for extended periods. Mg2+ in the form of MgATP2- is required for all the phosphorylation reactions of the cell. These and related observations are imaged in the membrane, magnesium, mitosis (MMM) model of cell proliferation control, which postulates that growth factors act by combining with membrane receptors to increase intracellular free Mg2+ levels and generate the coordinate response that leads ultimately to mitosis. The MMM model also proposes that the increased Mg2+ activates phosphorylation of two proteins by mTOR, a key reaction of the PI-3K pathway. Those two proteins directly regulate the initiation of protein synthesis, the driving force of the process.


Asunto(s)
Membrana Celular/metabolismo , Proliferación Celular , Magnesio/metabolismo , Mitosis/fisiología , Células Cultivadas , Sustancias de Crecimiento/metabolismo , Modelos Biológicos
11.
Neurology ; 62(12): 2283-6, 2004 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-15210895

RESUMEN

OBJECTIVE: To characterize cognitive status in a sample of individuals with late-onset GM2 gangliosidosis (commonly referred to as late-onset Tay-Sachs disease). METHODS: Seventeen subjects (13 men, 4 women) diagnosed with GM2 gangliosidosis were evaluated. Subjects ranged in age from 18 to 56 years and were in various stages of disease progression. Subjects underwent comprehensive neuropsychological assessment. Impairment was defined as performance more than 1.6 SD below the normative mean. RESULTS: Group mean performance was within the denoted normal range on all measures except on a task assessing visual sequencing and set shifting. Approximately one-half of the sample scored in the impaired range on measures of processing speed, visual sequencing, and set shifting. One-third of the sample also scored in the impaired range on measures of delayed verbal recall. Impairment tended to be restricted to a subset of the sample, as 5 of the 14 subjects able to undergo formal testing accounted for 70% of the total number of impaired scores. If the three subjects unable to participate in formal testing are also considered impaired, 47% of the current sample exhibited significant cognitive impairment in at least one cognitive domain. CONCLUSION: In late-onset GM2 gangliosidosis, there is a risk of impairment in executive functioning and memory as well as cerebellar dysfunction. Dementia was not present in any subjects in the current sample.


Asunto(s)
Cognición , Gangliosidosis GM2/fisiopatología , Adolescente , Adulto , Edad de Inicio , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
12.
Phys Rev Lett ; 93(26 Pt 1): 262001, 2004 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-15697968

RESUMEN

We have compared the p and p angular distributions in 117 x 10(6) Xi- -->Lambdapi- -->ppi-pi- and 41 x 10(6) Xi+ -->Lambda pi+ -->p pi+pi+ decays using a subset of the data from the HyperCP experiment (E871) at Fermilab. We find no evidence of CP violation, with the direct-CP-violating parameter AXiLambda identical with (alphaXialphaLambda-alpha Xialpha Lambda)/(alphaXialphaLambda+alphaXialphaLambda)=[0.0+/-5.1(stat)+/-4.4(syst)] x 10(-4).

13.
Qual Saf Health Care ; 12(6): 405-10, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14645754

RESUMEN

BACKGROUND: Despite the emphasis on patient safety in health care, few organizations have evaluated the extent to which safety is a strategic priority or their culture supports patient safety. In response to the Institute of Medicine's report and to an organizational commitment to patient safety, we conducted a systematic assessment of safety at the Johns Hopkins Hospital (JHH) and, from this, developed a strategic plan to improve safety. The specific aims of this study were to evaluate the extent to which the culture supports patient safety at JHH and the extent to which safety is a strategic priority. METHODS: During July and August 2001 we implemented two surveys in disparate populations to assess patient safety. The Safety Climate Scale (SCS) was administered to a sample of physicians, nurses, pharmacists, and other ICU staff. SCS assesses perceptions of a strong and proactive organizational commitment to patient safety. The second survey instrument, called Strategies for Leadership (SLS), evaluated the extent to which safety was a strategic priority for the organization. This survey was administered to clinical and administrative leaders. RESULTS: We received 395 completed SCS surveys from 82% of the departments and 86% of the nursing units. Staff perceived that supervisors had a greater commitment to safety than senior leaders. Nurses had higher scores than physicians for perceptions of safety. Twenty three completed SLS surveys were received from 77% of the JHH Patient Safety Committee members and 50% of the JHH Management Committee members. Management Committee responses were more positive than Patient Safety Committee, indicating that management perceived safety efforts to be further developed. Strategic planning received the lowest scores from both committees. CONCLUSIONS: We believe this is one of the first large scale efforts to measure institutional culture of safety and then design improvements in health care. The survey results suggest that strategic planning of patient safety needs enhancement. Several efforts to improve our culture of safety were initiated based on these results, which should lead to measurable improvements in patient safety.


Asunto(s)
Centros Médicos Académicos/organización & administración , Actitud del Personal de Salud , Errores Médicos/prevención & control , Cultura Organizacional , Administración de la Seguridad/organización & administración , Centros Médicos Académicos/normas , Baltimore , Prioridades en Salud , Humanos , Liderazgo , Personal de Hospital/psicología , Análisis de Sistemas
14.
Phys Rev Lett ; 91(3): 031601, 2003 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-12906410

RESUMEN

Based on 1.35 x 10(6) polarized Xi(-) events, we measure the parameter phi(Xi) to be -1.61 degrees +/-2.66 degrees +/-0.37 degrees for the Xi(-)-->Lambda pi(-) decay. New results for the parameters beta(Xi) and gamma(Xi) are also presented. Assuming that the CP-violating phase difference is negligible, we deduce the strong phase difference between the P-wave and S-wave amplitudes of the Lambda pi final state to be 3.17 degrees +/-5.28 degrees +/-0.73 degrees, reducing the uncertainty in estimating the level of CP violation in Xi-hyperon decay.

15.
Phys Rev Lett ; 88(11): 111801, 2002 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-11909394

RESUMEN

Using data collected with the HyperCP (E871) spectrometer during the 1997 fixed-target run at Fermilab, we report the first observation of the decay K--->pi(-)mu(+)mu(-) and new measurements of the branching ratios for K+/--->pi(+/-)mu(+)mu(-). By combining the branching ratios for the decays K+-->pi(+)mu(+)mu(-) and K--->pi(-)mu(+)mu(-), we measure Gamma(K+/--->pi(+/-)mu(+)mu(-))/Gamma(K+/--->all) = (9.8+/-1.0+/-0.5)x10(-8). The CP asymmetry between the rates of the two decay modes is [Gamma(K+-->pi(+)mu(+)mu(-))-Gamma(K--->pi(-)mu(+)mu(-))]/[Gamma(K+-->pi(+)mu(+)mu(-))+Gamma(K--->pi(-)mu(+)mu(-))] = -0.02+/-0.11+/-0.04.

16.
Carcinogenesis ; 22(12): 1903-30, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11751421

RESUMEN

B[a]P (benzo[a]pyrene) has been used as a prototype carcinogenic PAH since its isolation from coal tar in the 1930's. One of its diol epoxides, BPDE-2, is considered its ultimate carcinogen on the basis of its binding to DNA, mutagenicity and extreme pulmonary carcinogenicity in newborn mice. However, BPDE-1 has a similar binding to DNA and mutagenicity but it is not carcinogenic. In addition, BPDE-2 is a weak carcinogen relative to B[a]P when repeatedly applied to mouse skin, the conventional assay site. Its carcinogenicity is increased when applied once as an initiator followed repeatedly by a promoter. This indicates a major role for promotion in carcinogenesis by PAHs. Promotion itself is a 2-stage process, the second of which is selective propagation of the initiated cells. Persistent hyperplasia underlies selection by promoters. The non-carcinogenicity of BPDE-1 has yet to be resolved. PAHs have long been considered the main carcinogens of cigarette smoke but their concentration in the condensate is far too low to account by themselves for the production of skin tumors. The phenolic fraction does however have strong promotional activity when repeatedly applied to initiated mouse skin. Several constituents of cigarette smoke are co-carcinogenic when applied simultaneously with repeated applications of PAHs. Catechol is co-carcinogenic at concentrations found in the condensate. Since cigarette smoking involves protracted exposure to all the smoke constituents, co-carcinogenesis simulates its effects. Both procedures, however, indicate a major role for selection in carcinogenesis by cigarette smoke. That selection may operate on endogenous mutations as well as those induced by PAHs. There are indications that the nicotine-derived NNK which is a specific pulmonary carcinogen in animals contributes to smoking-induced lung cancer in man. Lung adenoma development by inhalation has been induced in mice by the gas phase of cigarette smoke. The role of selection has not been evaluated in either of these cases.


Asunto(s)
Carcinógenos/toxicidad , Nicotiana/efectos adversos , Hidrocarburos Policíclicos Aromáticos/toxicidad , Humo/efectos adversos , Animales , Benzo(a)pireno/metabolismo , Benzo(a)pireno/toxicidad , Carcinógenos/química , Carcinógenos/metabolismo , Transformación Celular Neoplásica/efectos de los fármacos , ADN/química , ADN/efectos de los fármacos , ADN/genética , ADN/metabolismo , Daño del ADN/efectos de los fármacos , Sinergismo Farmacológico , Humanos , Mutágenos/química , Mutágenos/metabolismo , Mutágenos/toxicidad , Neoplasias/inducido químicamente , Neoplasias/etiología , Neoplasias/genética , Neoplasias/patología , Hidrocarburos Policíclicos Aromáticos/química , Hidrocarburos Policíclicos Aromáticos/metabolismo
17.
J Bacteriol ; 183(24): 7076-86, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11717265

RESUMEN

The cydAB genes from Mycobacterium smegmatis have been cloned and characterized. The cydA and cydB genes encode the two subunits of a cytochrome bd oxidase belonging to the widely distributed family of quinol oxidases found in prokaryotes. The cydD and cydC genes located immediately downstream of cydB encode a putative ATP-binding cassette-type transporter. At room temperature, reduced minus oxidized difference spectra of membranes purified from wild-type M. smegmatis displayed spectral features that are characteristic of the gamma-proteobacterial type cytochrome bd oxidase. Inactivation of cydA or cydB by insertion of a kanamycin resistance marker resulted in loss of d-heme absorbance at 631 nm. The d-heme could be restored by transformation of the M. smegmatis cyd mutants with a replicating plasmid carrying the highly homologous cydABDC gene cluster from Mycobacterium tuberculosis. Inactivation of cydA had no effect on the ability of M. smegmatis to exit from stationary phase at 37 or 42 degrees C. The growth rate of the cydA mutant was tested under oxystatic conditions. Although no discernible growth defect was observed under moderately aerobic conditions (9.2 to 37.5 x 10(2) Pa of pO(2) or 5 to 21% air saturation), the mutant displayed a significant growth disadvantage when cocultured with the wild type under extreme microaerophilia (0.8 to 1.7 x 10(2) Pa of pO(2) or 0.5 to 1% air saturation). These observations were in accordance with the two- to threefold increase in cydAB gene expression observed upon reduction of the pO(2) of the growth medium from 21 to 0.5% air saturation and with the concomitant increase in d-heme absorbance in spectra of membranes isolated from wild-type M. smegmatis cultured at 1% air saturation. Finally, the cydA mutant displayed a competitive growth disadvantage in the presence of the terminal oxidase inhibitor, cyanide, when cocultured with wild type at 21% air saturation in an oxystat. In conjunction with these findings, our results suggest that cytochrome bd is an important terminal oxidase in M. smegmatis.


Asunto(s)
Citocromos/metabolismo , Proteínas del Complejo de Cadena de Transporte de Electrón , Proteínas de Escherichia coli , Genes Bacterianos , Mycobacterium smegmatis/metabolismo , Oxidorreductasas/metabolismo , Presión Atmosférica , Cianuros/farmacología , Grupo Citocromo b , Citocromos/análisis , Citocromos/genética , Transporte de Electrón , Regulación Bacteriana de la Expresión Génica , Pruebas de Sensibilidad Microbiana , Modelos Biológicos , Mutación , Mycobacterium smegmatis/genética , Oxidorreductasas/genética , Oxígeno/farmacología , Consumo de Oxígeno , Espectrofotometría
18.
Artículo en Inglés | MEDLINE | ID: mdl-11597107

RESUMEN

Entrapped non-aqueous liquid phase (NAPL) pollutants (e.g., fuels) constitute one of the biggest current problems in the bioremediation efforts of contaminated soil and aquifers worldwide. On site, in situ surfactant-enhanced bioremediation, in the presence of sufficient nutrients and dissolved oxygen, has the potential of becoming the remediation method of choice in terms of both technological and economical feasibility. This approach was applied in our lab-scale column-based flow system with the aid of which an optimized, below CMC, of biodegradable surfactant-nutrient surfactant mix has been established for the best solubilization/ mobilization of NAPL (hexane, toluene, kerosene and their mixtures as "representatives") in sandy matrix. For kerosene, the highest f values (the enhancement factors) were obtained for the systems containing either the amphoteric cocoamphodiacetate or the anionic linear dodecylbenzene sulfonate (0.1-0.3 g/L) with one or both the nutrient-surfactants L and B (0.05 g/L).


Asunto(s)
Contaminación Ambiental/prevención & control , Hidrocarburos/análisis , Contaminantes del Suelo/análisis , Tensoactivos/química , Contaminantes Químicos del Agua/análisis , Biodegradación Ambiental , Estudios de Factibilidad , Israel , Modelos Químicos , Solubilidad
19.
Artículo en Inglés | MEDLINE | ID: mdl-11597113

RESUMEN

This study originated from an accidental event of diesel oil contamination in a loam soil area of 7,000 m2. Approximately a volume of 1,300 m3 of diesel oil was released into the environment. Reclamation of the contaminated soil by on-site bioremediation was selected as the most appropriate treatment method. A major concern was associated with the nature of the local loam soil. Loam has a very low hydraulic conductivity and very quickly becomes impermeable after its contact with water. The bioremediation approach incorporated excavation of the contaminated soil, mixing it with an agent, which increased its permeability. Following this preliminary treatment came the construction of bioreactors as a suitable environment of nutrients, moisture, dissolved oxygen, and enriched culture of microorganisms, which enabled breakdown of the diesel oil. This case study indicated that the target of 99% of diesel oil clean up could be achieved by using the technology of on-site bioremediation. The selected treatment method was found to be technologically and economically feasible. However, some improvement in the application of the basic treatment approach might increase the bioremediation efficiency.


Asunto(s)
Biodegradación Ambiental , Contaminación Ambiental/prevención & control , Aceites Combustibles/análisis , Contaminantes del Suelo/análisis , Suelo/análisis , Reactores Biológicos , Cromatografía de Gases , Israel , Permeabilidad
20.
J Clin Gastroenterol ; 33(5): 393-6, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11606856

RESUMEN

The administration of multivitamins to patients receiving home parenteral nutrition (HPN) was decreased from once daily to three times weekly during the parenteral multivitamin shortage in 1997. Blood vitamin levels were measured to examine whether the decrement in the infused vitamins affected the levels. Six patients with normal renal and liver function, receiving HPN for 6 months to 10 years, were studied 6 months after the institution of 10 mL of multivitamins thrice weekly. Two patients with renal insufficiency who required hemodialysis and HPN were also studied. Multivitamin administration was eliminated in one patient and was reduced to once weekly when elevated pyridoxine levels were found in association with possible neurotoxicity. Five of the six patients with normal renal function had low serum ascorbic acid levels. Serum riboflavin levels were found to be low in one patient, serum pyridoxine was low in one, serum retinoids were low in three, and serum niacin was low in one. There were no clinically obvious untoward effects caused by the vitamin deficiencies. Each of the dialysis patients had elevated serum pyridoxine levels and had some neurologic disturbance (peripheral neuropathy, involuntary movements). The serum pyridoxine levels fell to normal in each after the cessation or decrease of the multivitamin preparation. Ascorbic acid levels were low in one patient and fell into abnormally low levels in the other when the parenteral multivitamins were reduced, but they corrected with the separate administration of intravenous vitamin C. In conclusion, the reduced administration of multivitamins in 1997 resulted in diminished ascorbic acid levels in seven of eight patients receiving total parenteral nutrition. Less often, low levels of retinoids, niacin, pyridoxine, and riboflavin were seen. Patients with chronic renal failure receiving HPN with multivitamins may develop elevated pyridoxine levels, which might result in neurologic sequelae.


Asunto(s)
Suplementos Dietéticos , Nutrición Parenteral Total en el Domicilio , Vitaminas/sangre , Adulto , Anciano , Ácido Ascórbico/sangre , Esquema de Medicación , Femenino , Humanos , Fallo Renal Crónico/sangre , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Política Nutricional , Piridoxina/sangre , Vitaminas/administración & dosificación
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