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1.
Glob Health Action ; 12(1): 1609313, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31116096

RESUMEN

Background: Community-based approaches have been identified as an effective strategy to address the growing burden of noncommunicable diseases (NCDs) worldwide. However, little is known about community as a concept among people living in socioeconomically disadvantaged settings and stakeholders' interactions and engagement in NCDs prevention and management. Objective: The aim of this study was to understand; (1) the meaning of community among people living in socioeconomically disadvantaged suburbs in Region Stockholm and (2) how communities interact and engage with stakeholders at local and regional levels for the prevention and management of type 2 diabetes (T2D). Methods: This qualitative study was conducted in three municipalities in Region Stockholm with a high proportion of migrants. Multiple data collection methods were used, including observations of community activities; interviews with community members, representatives of public authorities and NGOs; and group interviews with healthcare providers. Data were analyzed using content analysis. Results: Community was perceived as living in close proximity with shared beliefs, values and resources. Although they recognized its social and cultural diversity, community members focused more on the commonalities of living in their neighborhood and less on their differences in country of birth and languages spoken. Several mismatches between awareness of community needs and the available skills and resources among stakeholders for T2D prevention were identified. Stakeholders expressed awareness of T2D risk and interest in addressing it in a culturally appropriate manner. Conclusion: Interaction between the communities and stakeholders was limited, as was engagement in T2D prevention and management. This highlights barriers in the collaboration between community, healthcare institutions and other stakeholders which consequently affect the implementation of preventive interventions. Innovative ways to link the community to the healthcare sector and other local government institutions are needed to build the capacity of health systems for T2D prevention in socioeconomically disadvantaged communities.


Asunto(s)
Servicios de Salud Comunitaria/organización & administración , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/prevención & control , Promoción de la Salud/organización & administración , Colaboración Intersectorial , Poblaciones Vulnerables/psicología , Poblaciones Vulnerables/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Diabetes Mellitus Tipo 2/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Factores Socioeconómicos , Suecia
2.
J Med Chem ; 27(5): 684-91, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6716406

RESUMEN

A series of N-[(dialkylamino)alkyl]-2-oxo-1- pyrrolidineacetamides was synthesized. The title compounds reversed electroconvulsive shock (ECS) induced amnesia in mice when administered subsequent to the ECS treatment and were inactive in a general observational test for central nervous system (CNS) activity. Active compounds exhibited an inverted U-shaped dose-response curve. Among the compounds with the broadest dose-response curve, as well as the most potent, were those with the N-[2-[bis(1-methylethyl)amino] ethyl] or 2,6- dimethylpiperidinoethyl residues as amide substituent. The N-(dialkylamino) substituent markedly enhances amnesia-reversal activity, with ethylene providing the optimal chain length. N-[2-[Bis(1-methylethyl)amino]ethyl] -2-oxo-1- pyrrolidineacetamide N-(dialkylamino) substituent was selected for preclinical toxicological evaluation, assigned the investigational number CI-879 and the U.S. adopted name ( USAN ) pramiracetam . Pramiracetam demonstrated a wide margin of safety in animals and was well tolerated in normal human volunteers. It has shown encouraging activity in an open label trial in patients with primary degenerative dementia (PDD or senile dementia of the Alzheimer's type).


Asunto(s)
Amnesia/tratamiento farmacológico , Pirrolidinas/uso terapéutico , Animales , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Electrochoque , Humanos , Masculino , Ratones , Ratones Endogámicos , Pirrolidinas/síntesis química , Relación Estructura-Actividad
3.
J Med Chem ; 28(5): 606-12, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-2859371

RESUMEN

On the basis of a structural model of the postsynaptic dopaminergic antagonist pharmacophore, a series of 1-[3-(diarylamino)propyl]piperidines and related compounds was synthesized and evaluated for potential antipsychotic activity. For a rapid measure of activity, the target compounds were initially screened in vitro for inhibition of [3H]haloperidol binding and in vivo in a test of locomotor activity. Behavioral efficacy of compounds identified from the initial screens was more accurately measured in rats by using a suppression of high base-line medial forebrain bundle self-stimulation test model. The propensity of these compounds for causing extrapyramidal side effects was evaluated by using a rat catalepsy method. On the basis of these test models, we have shown that the methine carbon of the 1-(4,4-diarylbutyl)piperidines can be advantageously replaced with a nitrogen atom. The 1-[3-(diarylamino)propyl]piperidines were less cataleptic than the corresponding 1-(4,4-diarylbutyl)piperidines. The compounds with the widest separation between efficacious dose and cataleptic dose are 8-[3-[bis(4-fluorophenyl)amino]propyl]-1-phenyl-1,3,8-triazaspiro [4. 5]decan-4-one (6), 1-[1-[3-[bis(4-fluorophenyl)amino]propyl]-4-piperidinyl]-1,3-dihydro- 2H-benzimidazol-2-one (11), 1-[1-[3-[bis(4-fluorophenyl)amino]propyl]-1,2,3,6-tetrahydro-4- pyridinyl]-1,3-dihydro-2H-benzimidazol-2-one (22), and 1-[3-[bis(4-fluorophenyl)amino]propyl]-4-(2-methoxyphenyl)piperazine (26).


Asunto(s)
Antipsicóticos/síntesis química , Catalepsia/inducido químicamente , Piperidinas/síntesis química , Animales , Antipsicóticos/toxicidad , Enfermedades de los Ganglios Basales/inducido químicamente , Unión Competitiva , Cuerpo Estriado/metabolismo , Haloperidol/metabolismo , Humanos , Técnicas In Vitro , Masculino , Ratones , Actividad Motora/efectos de los fármacos , Piperazinas/síntesis química , Piperazinas/farmacología , Piperazinas/toxicidad , Piperidinas/farmacología , Piperidinas/toxicidad , Ratas , Receptores Dopaminérgicos/efectos de los fármacos , Receptores Dopaminérgicos/metabolismo , Autoestimulación/efectos de los fármacos , Relación Estructura-Actividad
4.
J Med Chem ; 29(10): 1953-61, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3020249

RESUMEN

The synthesis and angiotensin converting enzyme (ACE) inhibiting activities of quinapril (CI-906, 22), its active diacid (CI-928, 33), and its dimethoxy analogue (CI-925, 25) are reported. These tetrahydro-3-isoquinolinecarboxylic acid derivatives possess equivalent in vitro potency and in vivo efficacy to enalapril. Sulfhydryl analogues with the same structural variation are also highly potent. In contrast, tetrahydro-1-isoquinolinecarboxylic acid and homologous isoindoline-1-carboxylic acid analogues show a striking divergence in potency between the two types, sulfhydryl analogues being essentially inactive, while non-sulfhydryl analogues are equipotent with the proline prototype. This is the first evidence suggesting that alternate binding modes may exist for the two major structural classes of small molecule ACE inhibitors.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina , Isoquinolinas/síntesis química , Tetrahidroisoquinolinas , Animales , Isoquinolinas/farmacología , Masculino , Conformación Molecular , Quinapril , Ratas , Ratas Endogámicas , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/farmacología
5.
Biosci Rep ; 4(5): 433-40, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6428486

RESUMEN

Replacement of unlabeled gamma-butyrobetaine with gamma-[2,3,4-2H6]butyrobetaine has a profound effect on the stoichiometry between decarboxylation of 2-oxoglutarate and hydroxylation in the reaction catalyzed by human gamma-butyrobetaine hydroxylase. The ratios between decarboxylation and hydroxylation are 1.16 with unlabeled and 7.48 with deuterated gamma-butyrobetaine as substrate. From these ratios an internal isotope effect of 41 has been calculated. DV in the overall reaction measured as 2- oxoglutarate decarboxylation is 2.5 and DV/K is 1.0. For gamma-butyrobetaine hydroxylase from Pseudomonas sp. AK 1, 2-oxoglutarate decarboxylation exceeds hydroxylation with 10% when deuterated gamma-butyrobetaine is used. No excess was found with unlabeled substrate and no internal isotope effect could be calculated. DV for the bacterial enzyme is 6.


Asunto(s)
Betaína/análogos & derivados , Oxigenasas de Función Mixta/metabolismo , Betaína/metabolismo , Dióxido de Carbono/biosíntesis , Carnitina/biosíntesis , Humanos , Riñón/enzimología , Cinética , Especificidad por Sustrato , Tritio , gamma-Butirobetaína Dioxigenasa
9.
Med Health Care Philos ; 3(3): 297-304, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11200030

RESUMEN

One problematic aspect of the rationality of medical practice concerns the relation between expert knowledge and non-expert knowledge. In medical practice it is important to match medical knowledge with the self-knowledge of the individual patient. This paper tries to study the problem of such matching by describing a model for technological paradigms and comparing it with an ideal of technological rationality. The professionalised experts tend to base their decisions and actions mostly on medical knowledge while the rationality of medicine also involves just as important elements of the personal evaluation and knowledge of the patients. Since both types of knowledge are necessary for rational decisions, the gap between the expert and the non-expert has to be bridged in some way. A solution to the problem is suggested in terms of pluralism, with the patient as ultimate decision-maker.


Asunto(s)
Toma de Decisiones , Participación del Paciente , Relaciones Médico-Paciente , Tecnología Biomédica , Competencia Clínica , Ética Médica , Conocimientos, Actitudes y Práctica en Salud , Humanos , Solución de Problemas , Terapéutica/métodos
10.
Theor Med Bioeth ; 20(2): 105-23, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10450662

RESUMEN

Should medicine be defined as the enterprise in charge of the health problems of society? If so, then any problem (individual, public, social or political) that can be reformulated as a "health problem" could serve as a goal of medicine. If, on the other hand, medicine--or medicine proper--is defined in terms of some limited goal and limited means, then some medical professionals would find themselves working in other fields than medicine. It could be of some importance to the patient to know whether the medical professional he meets is engaged in medical practice (aiming at the patient's health), research, public health or some other project which involves medical competence. Obviously, some of these enterprises may have conflicting goals. This paper will analyse various candidates for being a model of medicine, discuss some of the consequences, and argue for a limited view of medical practice.


Asunto(s)
Medicina , Objetivos Organizacionales , Filosofía Médica , Práctica Profesional , Rol Profesional , Humanos , Modelos Organizacionales , Rol de la Enfermera , Salud Pública , Investigación , Asignación de Recursos
11.
Theor Med Bioeth ; 20(3): 229-44, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10474310

RESUMEN

A suitable demarcation between pure science and applied research can be drawn in terms of their goals. This distinction of goals has methodological and cultural consequences. If the demarcation is accepted, what does the connection between the two enterprises look like? What is the role of science in medical practice? The Baconian answer to this question is discussed and criticised as too linear. A second answer may be that pure science has no part at all in medicine. This too can be criticised as too simplistic. A third answer is suggested in which pure science plays the role of being an instrument for interpreting observations and problems, and of being a source of inspiration for technological research programs.


Asunto(s)
Ciencia del Laboratorio Clínico , Medicina , Práctica Profesional , Investigación , Ciencia , Humanos , Modelos Teóricos
12.
Biochem J ; 223(1): 119-27, 1984 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-6497835

RESUMEN

gamma-Butyrobetaine hydroxylase [4-trimethylaminobutyrate, 2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating), EC 1.14.11.1] from human kidney was resolved into three forms by chromatofocusing. After further chromatography on an anion-exchanger, each form appeared as a single band on electrophoresis in polyacrylamide gel containing sodium dodecyl sulphate. The isoelectric points of isoenzymes 1, 2 and 3 were 5.6, 5.7 and 5.8 respectively, as estimated by isoelectric focusing. Their specific activities were 17-29 mu kat/g of protein. The concentrations of the three isoenzymes were about equal, possibly slightly lower for isoenzyme 1. The requirement for Fe2+ and the Km values for gamma-butyrobetaine and 2-oxoglutarate were about the same for the different enzyme forms. L- and D-Carnitine caused decarboxylation of 2-oxoglutarate to the same extent (8 and 29%) with the three forms. The enzyme forms had the same mass, 64 kDa, as determined by gel filtration in nondenaturing media. The same subunit mass, 42 kDa, was obtained for the multiple forms by electrophoresis in polyacrylamide gels containing sodium dodecyl sulphate. Isoenzyme 2 was resolved into two protein bands by isoelectric focusing in polyacrylamide gels containing urea. Isoenzyme 1 contained only one of these bands and isoenzyme 3 the other. The three enzyme forms of gamma-butyrobetaine hydroxylase thus appear to be dimeric combinations of two subunits differing in charge but not in size. gamma-Butyrobetaine hydroxylase from crude extracts of human, rat and calf liver was also separated into multiple forms by a chromatofocusing technique. The isoenzyme pattern was the same in human liver and kidney. The technique used to resolve the mammalian enzymes gave no evidence for the presence of multiple forms of the bacterial enzyme from Pseudomonas sp. AK 1.


Asunto(s)
Isoenzimas , Oxigenasas de Función Mixta , Animales , Bovinos , Cromatografía por Intercambio Iónico , Cromatografía Liquida , Electroforesis en Gel de Poliacrilamida , Humanos , Isoenzimas/aislamiento & purificación , Riñón/enzimología , Cinética , Hígado/enzimología , Oxigenasas de Función Mixta/aislamiento & purificación , Oxigenasas de Función Mixta/metabolismo , Pseudomonas/enzimología , Ratas , Especificidad de la Especie , gamma-Butirobetaína Dioxigenasa
13.
Scand J Clin Lab Invest ; 42(6): 477-85, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7156861

RESUMEN

The activity of gamma-butyrobetaine hydroxylase [4-trimethylaminobutyrate: oxygen oxidoreductase (3-hydroxylating), EC 1.14.11.1] was determined in different parts of a human kidney removed at surgery and in five perfused human cadaver kidneys. The activity in the 100,000 g supernatant fraction of a homogenate of whole kidneys was 48 nkat X g-1 protein (range 32-70 nkat X g-1protein). The cortex and outer medulla had four to six times higher activity than the inner medulla. A 60-fold purification from the soluble fraction of kidney homogenates with a 40% recovery was achieved by ammonium sulphate fractionation followed by DEAE-cellulose and hydroxylapatite chromatography. The enzyme had a specific activity of 2.4 mukat X g-1 protein but was contaminated to a minor degree by other proteins as judged by polyacrylamide gel electrophoresis. The Km values for gamma-butyrobetaine, 2-oxoglutarate and oxygen were 0.2 mmol/l, 0.3 mmol/l and 5.5% (by volume in the gas phase). There was an absolute requirement for ferrous ion. Half-maximal activity was reached with 10 mumol/l of Fe2+ in phosphate buffer (14 mmol/l) at pH 6.5. With a reaction time of 30 min ascorbate and catalase stimulated the reaction seven- and fivefold, respectively. Optimal pH value for the reaction was 6.2-6.5 in phosphate buffer. Decarboxylation of 2-oxoglutarate in the presence of 4-trimethylaminocrotonate or 4-dimethylaminobutyrate was 40 and 20%, respectively, of that with gamma-butyrobetaine as substrate. None of several compounds chemically related to 2-oxoglutarate, including oxaloacetate, stimulated gamma-butyrobetaine hydroxylation when tested in the absence of 2-oxoglutarate. We conclude that the requirements of the human kidney enzyme are similar to those previously reported for this enzyme from other sources.


Asunto(s)
Riñón/enzimología , Oxigenasas de Función Mixta/metabolismo , Cromatografía , Cromatografía DEAE-Celulosa , Descarboxilación , Electroforesis en Gel de Poliacrilamida , Humanos , Concentración de Iones de Hidrógeno , Cinética , gamma-Butirobetaína Dioxigenasa
14.
Biochemistry ; 16(10): 2181-8, 1977 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-861203

RESUMEN

gamma-Butyrobetaine hydroxylase (4-trimethylaminobutyrate, 2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating), EC 1.14.11.1) has been isolated from Pseudomonas sp AK 1 by ion-exchange, adsorption, and molecular-sieving chromatography. The preparation was homogeneous as judged from electrophoresis in agarose and polyacrylamide gels, isoelectric focusing, and equilibrium sedimentation. The molecular mass was 95 kdaltons as determined by sedimentation equilibrium centrifugation. From electrophoresis in polyacrylamide gel the molecular mass was estimated to 92 kdaltons, from gel filtration through columns of Sephadex G-200 to 86 kdaltons, and from gel filtration through thin layers of Sephadex G-150 and G-200 to 82 kdaltons. Calculation of molecular mass from Stokes radius, sedimentation coefficient, and partial specific volume gave a value of 96 kdaltons, and from the sedimentation coefficient, 93 kdaltons. Gel filtration through Sephadex G-200 in 6 M guanidinium chloride and electrophoresis in polyacrylamide gel containing 3.5 mM sodium dodecyl sulfate resulted in single bands with mobilities corresponding to molecular masses of 39 and 37 kdaltons, respectively, indicating that the enzyme is composed of two polypeptides chains with similar size. NH2-terminal amino acid sequencing in three cycles resulted in two amino acids in each cycle (Ala + Asn, Ala + Ile, Ala + Ile). The Stokes radius was 3.8 nm, corresponding to a diffusion coefficient of 5.7 X 10(-7) cm2/s. A sedimentation coefficient of 5.8 X 10(-13) s and a frictional ratio of 1.26 was found. The partial specific volume was 0.729 mL/g at 20 degrees C as calculated from amino acid analysis. The isoelectric point was 5.1, as determined by isoelectric focusing analysis. The light absorption in the ultraviolet and visible regions was that of a protein without light-absorbing prosthetic groups. The absorption coefficient at 280 nm of a 1.0% solution at pH 6.5 was 12.6. Amino acid analysis by ion-exchange chromatography showed a half-cystine content of 19 mol per 95 kg of protein (23 residues/1000). Thirteen sulfhydryl groups were found by colorimetric analysis before as well as after reduction with NaBH4, indicating absence of disulfide bonds. Less than 0.1 mol of iron was found per mol of enzyme.


Asunto(s)
Oxigenasas de Función Mixta , Pseudomonas/enzimología , Aminoácidos/análisis , Betaína/análogos & derivados , Sitios de Unión , Butiratos , Carbohidratos/análisis , Disulfuros/análisis , Hierro/análisis , Oxigenasas de Función Mixta/aislamiento & purificación , Unión Proteica , Conformación Proteica
15.
J Inherit Metab Dis ; 12(2): 108-11, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2502670

RESUMEN

Carnitine uptake has been studied in fibroblasts from a case of hereditary carnitine deficiency and in relatives. There was no evidence for carrier-dependent uptake in cells from the patient. The mother and probably the healthy sister had an impaired uptake. The results show that the defect in this form of carnitine deficiency is an inability to establish a concentration gradient over the cell membrane.


Asunto(s)
Carnitina/deficiencia , Carnitina/metabolismo , Transporte Biológico , Carnitina/genética , Células Cultivadas , Femenino , Fibroblastos/metabolismo , Humanos , Cinética , Mutación
16.
Scand J Clin Lab Invest ; 52(5): 361-72, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1514015

RESUMEN

Treatment of 17 children aged 2-9.5 years with a combination of pivmecillinam and pivampicillin (250-500 mumol 24 h-1) for more than 1 year resulted in a reduction of the free carnitine concentration in serum and muscle to less than 10% of the mean reference value. The decline in serum was slow, with an estimated half-life of about 5 months. Spontaneous replenishment occurred at about the same slow rate. Thus, there is no increase in endogenous carnitine synthesis as a response to increased demand of carnitine for detoxification. Supplementation with carnitine during treatment required at least a four-fold molar excess over pivalic acid to achieve and sustain a normal carnitine concentration. The replenishment of carnitine occurred with a half-life of 1.1-3.0 months. From determination of muscle-carnitine concentration in patients treated with pivaloyl-containing antibiotics and in patients with organic aciduris, we conclude that serum carnitine is a good predictor of carnitine stores in the body. Six non-supplemented patients with a serum free-carnitine concentration of 0.7-2.6 mumol l-1 had an inadequate ketone-body increase during a 24-h fast. Vomiting, nausea and tiredness occurred in three cases following the fasting period. After normalization of the serum-carnitine concentration, a normal response to fasting was observed. Thus, in some organic acidurias, for example medium-chain acyl-CoA dehydrogenase deficiency, a low liver concentration of carnitine may be an important contributing factor to hypoglycaemic and Reye-like attacks. We believe that prodrugs which contain pivalic acid should be avoided if acceptable alternatives exist. If used, supplementation with at least four-fold molar excess of carnitine is advisable.


Asunto(s)
Amdinocilina Pivoxil/efectos adversos , Carnitina/deficiencia , Ayuno/fisiología , Ácidos Pentanoicos/efectos adversos , Pivampicilina/efectos adversos , Profármacos/efectos adversos , Amdinocilina Pivoxil/administración & dosificación , Carnitina/metabolismo , Niño , Preescolar , Femenino , Homeostasis , Humanos , Músculos/metabolismo , Pivampicilina/administración & dosificación , Valores de Referencia
17.
Biochem J ; 205(2): 339-44, 1982 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-6291507

RESUMEN

The possible role of superoxide anion in 2-oxoglutarate-coupled dioxygenase reactions has been investigated. gamma-Butyrobetaine hydroxylase (EC 1.14.11.1) was inhibited by human erythrocyte superoxide dismutase (EC 1.15.1.1), probably due to release of Cu(2+) or Zn(2+), as the inhibition was more pronounced after heat-inactivation of the dismutase and as Cu(2+) was a potent inhibitor. Bovine superoxide dismutase and the Mn(2+)-containing superoxide dismutase from Escherichia coli were not inhibitory. Superoxide anion generated from xanthine/xanthine oxidase was not stimulatory and could not replace ascorbate. Thymine 7-hydroxylase (EC 1.14.11.6) and thymidine 2'-hydroxylase (EC 1.14.11.3) were not inhibited by erythrocyte superoxide dismutase or stimulated by superoxide anion. gamma-Butyrobetaine hydroxylase was inhibited by a number of low-molecular-weight compounds, such as tetranitromethane, Nitro Blue Tetrazolium, adrenaline and Tiron, which may act as scavengers of superoxide anion. Involvement of this radical in other oxygenase reactions has been inferred from the findings that they were inhibitory for the respective enzymes. Several of these compounds also inhibited gamma-butyrobetaine hydroxylase. It could be concluded from these experiments, however, that mechanisms other than disposal of superoxide anion might equally well be operative, such as hydrophobic interaction with the enzyme protein and interaction with compounds required for full enzymic activity, e.g. iron and ascorbate. The results appear to rule out a requirement for superoxide anion generated in free solution, and have not yielded evidence for participation of enzyme-bound superoxide anion in 2-oxoglutarate-dependent hydroxylations.


Asunto(s)
Ácidos Cetoglutáricos/metabolismo , Oxigenasas de Función Mixta/metabolismo , Oxígeno/metabolismo , Superóxidos/metabolismo , Cobre/metabolismo , Hidroquinonas/metabolismo , Hidroxilación , Nitroazul de Tetrazolio/metabolismo , Quinonas/metabolismo , Superóxido Dismutasa/metabolismo , Tetranitrometano/metabolismo , gamma-Butirobetaína Dioxigenasa
18.
Eur J Biochem ; 213(3): 1075-80, 1993 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-8504802

RESUMEN

gamma-Butyrobetaine hydroxylase is a 2-oxoglutarate-dependent dioxygenase that catalyzes the hydroxylation of gamma-butyrobetaine to carnitine, the last step in the biosynthesis of carnitine from lysine. The primary structure of the enzyme from Pseudomonas sp. AK1 has been determined. Sequence analysis of the intact protein and of peptides from essentially three different digests established the presence of a peptide chain containing 383 residues, and an N-terminal truncated form of 382 residues. The two chains have molecular masses of 43,321 Da and 43,207 Da, respectively, and are identical except for the presence or absence of an N-terminal asparagine residue; the shorter form starts with an alanine residue. In preparations of the dimeric protein, the two chains occur in an approximate ratio of 1:1. There are nine cysteine residues and 13 histidine residues, i.e. amino acids which have been postulated as ligands for iron binding. In spite of functional similarities, there appears to be no clear sequence similarities with any of the other mammalian 2-oxoglutarate-dependent dioxygenases so far characterized.


Asunto(s)
Oxigenasas de Función Mixta/química , Pseudomonas/enzimología , Secuencia de Aminoácidos , Aminoácidos/análisis , Humanos , Riñón/enzimología , Datos de Secuencia Molecular , Análisis de Secuencia , gamma-Butirobetaína Dioxigenasa
19.
Biochem Mol Med ; 55(1): 77-9, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7551831

RESUMEN

Treatment with pivalic acid containing prodrugs has been shown to cause carnitine depletion by loss of pivaloyl carnitine in urine. A 7-day standard pivmecillinam treatment of adults lead to a marked decrease of the free serum carnitine concentration (44.6 to 12.9 mumol/liter), whereas no change was seen in those given norfloxacine (40.0 to 40.5 mumol/liter). In some patients irrespective of age the free serum carnitine concentration was decreased to levels (around 10 mumol/liter) at which an impaired ketone-body production may occur. Therefore, there is reason for cautious use of this type of drug irrespective of the age of the patients.


Asunto(s)
Amdinocilina Pivoxil/efectos adversos , Carnitina/sangre , Penicilinas/efectos adversos , Ácidos Pentanoicos/efectos adversos , Adolescente , Adulto , Factores de Edad , Anciano , Amdinocilina Pivoxil/administración & dosificación , Carnitina/deficiencia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Norfloxacino/administración & dosificación , Penicilinas/administración & dosificación , Ácidos Pentanoicos/administración & dosificación , Profármacos/administración & dosificación , Profármacos/efectos adversos , Factores de Riesgo , Factores de Tiempo , Infecciones Urinarias/tratamiento farmacológico
20.
Biochem Med Metab Biol ; 52(1): 18-21, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7917463

RESUMEN

Long-term treatment with pivalic acid prodrug results in impaired ketone-body production. Therefore, it was of interest to investigate whether short-term treatment had any influence on the fatty acid oxidation. In this study six healthy males were given 1200 mg per day of pivmecillinam for 12 days to induce carnitine deficiency. The concentration of free carnitine in serum was reduced from a mean of 42.8 mumol/liter (range, 31-48) to 11.6 mumol/liter (range, 7.0-24), but the muscle carnitine concentration was not reduced. A 36-h fasting test was performed before and after drug administration to study the effect on ketone-body production. After treatment, the two subjects with the lowest level of serum free carnitine at the end of the fasting period had impaired ketogenesis. This indicates a carnitine deficiency in the liver which was reflected in the free carnitine concentration for by mobilization of muscle carnitine. We conclude that there is a substantial risk to develop carnitine deficiency and impaired fatty acid oxidation in the liver during short-term treatment with drugs conjugated with pivalic acid.


Asunto(s)
Carnitina/deficiencia , Cuerpos Cetónicos/biosíntesis , Ácidos Pentanoicos/farmacología , Profármacos/farmacología , Adulto , Amdinocilina Pivoxil/farmacología , Carnitina/sangre , Carnitina/metabolismo , Ácidos Grasos/metabolismo , Ácidos Grasos no Esterificados/sangre , Humanos , Hígado/metabolismo , Masculino , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Oxidación-Reducción
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