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1.
Res Pract Thromb Haemost ; 7(1): 100051, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36873563

RESUMEN

Background: In upper extremity thrombosis research, the occurrence of upper extremity postthrombotic syndrome (UE-PTS) is commonly used as the main outcome parameter. However, there is currently no reporting standard or a validated method to assess UE-PTS presence and severity. In a recent Delphi study, consensus was reached on a preliminary UE-PTS score, combining 5 symptoms, 3 signs, and the inclusion of a functional disability score. However, no consensus was reached on which functional disability score to be included. Objectives: The aim of the current Delphi consensus study was to determine the specific type of functional disability score to finalize UE-PTS score. Methods: This Delphi project was designed as a three-round study using open text questions, statements with 7-point Likert scales, and multiple-choice questions. The CREDES recommendations for Delphi studies were applied. In this context, a systematic review was conducted before the start of the Delphi rounds to identify the available functional disability scores as available in the literature and present these to the expert panel. Results: Thirty-five of 47 initially invited international experts from multiple disciplines completed all the Delphi rounds. In the second round, consensus was reached on the incorporation of the quick disabilities of the arm, shoulder, and hand (QuickDASH) in the UE-PTS score, rendering the third round obsolete. Conclusion: Consensus was reached that the QuickDASH should be incorporated in the UE-PTS score. The UE-PTS score will need to be validated in a large cohort of patients with upper extremity thrombosis before it can be used in clinical practice and future research.

2.
Pharmacol Res ; 65(6): 592-602, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22373658

RESUMEN

Epicatechin is a widely consumed dietary flavonoid and there is substantial evidence that it contributes to the health benefits reported for flavanol-rich cocoa products including dark chocolate. Numerous reports have described the appearance of epicatechin and epicatechin phase-2 conjugates (sulfates and glucuronides of epicatechin and methylepicatechin) in blood and urine samples of subjects following ingestion of epicatechin. The most widely reported method of quantifying total epicatechin in plasma and urine samples involves hydrolysis with a mixture of ß-glucuronidase and sulfatase to convert the conjugates to epicatechin aglycone which is subsequently quantified. We observed a lack of hydrolysis of epicatechin sulfates and methylepicatechin sulfates using commercial sulfatases and investigated this further. Samples of urine or plasma from subjects who had consumed epicatechin were subjected to enzyme hydrolysis and then analysed using LC-MS/MS, or analysed without enzyme hydrolysis. Attempts to increase the extent of hydrolysis of epicatechin conjugates were made by increasing the amount of enzyme, hydrolysis pH and length of incubations, and using alternative sources of enzyme. The standard hydrolysis conditions failed to hydrolyse the majority of epicatechin sulfates and methylepicatechin sulfates. Even when the quantity of enzyme and incubation period was increased, the pH optimised, or alternative sources of sulfatases were used, epicatechin monosulfates and methylepicatechin monosulfates remained as major peaks in the chromatograms of the samples. An assessment of literature data strongly suggested that the majority of reports where enzyme hydrolysis was used had significantly underestimated epicatechin bioavailability in humans. Methods for quantifying epicatechin concentrations in blood and urine need to take account of the lack of hydrolysis of (methyl)epicatechin-sulfates, for example by quantifying these directly using LC-MS/MS.


Asunto(s)
Arilsulfatasas/metabolismo , Catequina/análogos & derivados , Ésteres del Ácido Sulfúrico/metabolismo , Administración Oral , Disponibilidad Biológica , Biotransformación , Catequina/administración & dosificación , Catequina/sangre , Catequina/metabolismo , Catequina/orina , Cromatografía Liquida , Estudios Cruzados , Inglaterra , Femenino , Glucuronidasa/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Hidrólisis , Masculino , Metilación , Reproducibilidad de los Resultados , Especificidad por Sustrato , Ésteres del Ácido Sulfúrico/administración & dosificación , Ésteres del Ácido Sulfúrico/sangre , Ésteres del Ácido Sulfúrico/orina , Espectrometría de Masas en Tándem , Factores de Tiempo
3.
Mol Genet Metab ; 102(2): 216-7, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20965758

RESUMEN

Succinic semialdehyde dehydrogenase deficiency is a slowly progressive to static neurological disorder featuring elevated concentrations of 4-hydroxybutyric acid in body fluids. We present two patients with elevated 4-hydroxybutyric acid in urine which was later shown to be linked to catheter usage.


Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico , Catéteres , Hidroxibutiratos/orina , 4-Butirolactona/orina , Errores Innatos del Metabolismo de los Aminoácidos/enzimología , Catéteres/normas , Discapacidades del Desarrollo , Femenino , Humanos , Hidroxibutiratos/sangre , Lactante , Recién Nacido , Enfermedad de la Orina de Jarabe de Arce/diagnóstico , Enfermedad de la Orina de Jarabe de Arce/enzimología , Succionato-Semialdehído Deshidrogenasa/deficiencia
4.
Clin Exp Dermatol ; 36 Suppl 2: 4-11, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21443598

RESUMEN

BACKGROUND: Alitretinoin (9-cis retinoic acid) is currently registered in many European countries and in Canada as the only licensed treatment for severe chronic hand eczema unresponsive to potent topical corticosteroids. Alitretinoin, like all retinoids, is teratogenic, and women of child-bearing potential must strictly adhere to pregnancy-prevention measures. AIM: To investigate the influence of alitretinoin on the pharmacokinetics (PK) of ethinyl estradiol/norgestimate (Ortho Tri-Cyclen 28(®)), a commonly prescribed combination oral contraceptive. METHODS: In total, 16 healthy premenopausal women received three consecutive cycles of the triphasic contraceptive ethinyl estradiol/norgestimate together with concomitant oral alitretinoin 40 mg once daily during cycle 2. Steady-state PK (noncompartmental analysis) of ethinyl estradiol, 17-deacetyl norgestimate, alitretinoin and its main metabolite 4-oxo-alitretinoin were assessed alone and in combination. RESULTS: The PK profiles of ethinyl estradiol and 17-deacetyl norgestimate were similar when contraceptives were given alone or with alitretinoin, and the area under the plasma concentration vs. time curve and the maximum concentration met the conventional criteria for PK equivalence. Similarly, the influence of ethinyl estradiol/norgestimate on systemic exposure to alitretinoin and 4-oxo-alitretinoin was not clinically relevant. Alitretinoin was well tolerated when given either alone or with ethinyl estradiol/norgestimate. CONCLUSIONS: There was no clinically relevant influence of alitretinoin on the PK of ethinyl estradiol/norgestimate, and no influence of ethinyl estradiol/norgestimate on systemic exposure to alitretinoin and 4-oxo-alitretinoin. Consequently, oral contraception with ethinyl estradiol/norgestimate is an appropriate primary method of birth control during alitretinoin treatment for women of childbearing potential.


Asunto(s)
Anticonceptivos Orales Combinados/sangre , Fármacos Dermatológicos/farmacología , Etinilestradiol/sangre , Norgestrel/análogos & derivados , Tretinoina/farmacología , Administración Oral , Adolescente , Adulto , Alitretinoína , Niño , Anticonceptivos Orales Combinados/administración & dosificación , Anticonceptivos Orales Combinados/efectos adversos , Fármacos Dermatológicos/efectos adversos , Fármacos Dermatológicos/sangre , Esquema de Medicación , Combinación de Medicamentos , Interacciones Farmacológicas , Etinilestradiol/administración & dosificación , Etinilestradiol/efectos adversos , Femenino , Humanos , Persona de Mediana Edad , Norgestrel/administración & dosificación , Norgestrel/efectos adversos , Norgestrel/sangre , Progesterona/sangre , Tretinoina/efectos adversos , Tretinoina/sangre , Adulto Joven
5.
Clin Exp Dermatol ; 36 Suppl 2: 12-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21443599

RESUMEN

BACKGROUND: Alitretinoin, like all retinoids, is teratogenic, and can only be given to women of childbearing potential if pregnancy is excluded and a strict contraceptive programme is followed. AIM: This study was designed to determine whether alitretinoin in the semen of men treated with alitretinoin poses a teratogenic risk to their female partners. METHODS: In total, 24 healthy men aged 18-45 years received alitretinoin 20 mg (n = 12) or 40 mg (n = 12), once daily for 14 days. Subjects in the 40 mg dose group provided ejaculate at baseline, on day 1, before and approximately 4 h after dosing on day 2, and at follow-up on study day 21 (± 2). RESULTS: Alitretinoin and 4-oxo-alitretinoin were detected in 11 of the 12 semen samples. The highest level of alitretinoin in semen was 7.92 ng/mL. Assuming an ejaculate volume of 10 mL, the amount of drug transferred in semen would be about 80 ng, 1/375,000 of a single 30 mg capsule. Complete absorption of 80 ng of alitretinoin from semen, presuming a volume of distribution confined to 5 L of circulating blood in the partner, would lead to an increase in plasma alitretinoin concentration of 0.016 ng/mL, which appears to be negligible compared with measured endogenous plasma levels. Increases in plasma levels of related retinoids are also negligible. CONCLUSIONS: Alitretinoin in the semen of men receiving up to 40 mg of oral alitretinoin per day is unlikely to be associated with teratogenic risk in their female partners. Barrier contraception is therefore not required for men taking alitretinoin.


Asunto(s)
Fármacos Dermatológicos/farmacocinética , Semen/metabolismo , Tretinoina/farmacocinética , Anomalías Inducidas por Medicamentos/etiología , Administración Oral , Adolescente , Adulto , Alitretinoína , Fármacos Dermatológicos/administración & dosificación , Fármacos Dermatológicos/efectos adversos , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo/métodos , Tretinoina/administración & dosificación , Tretinoina/efectos adversos , Adulto Joven
6.
Clin Exp Dermatol ; 36 Suppl 2: 18-23, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21443600

RESUMEN

BACKGROUND: Previous studies have shown that concomitant administration of food may enhance the bioavailability of oral retinoids. AIM: To assess the influence of food on the pharmacokinetics (PK) of alitretinoin after a single oral dose. METHODS: This was a single-dose, open-label, randomized, crossover study, which enrolled 30 healthy men, aged 18-44 years. Subjects received sequential doses of alitretinoin 40 mg either after fasting (treatment A) or 5 min after completion of a standard breakfast (treatment B), with the dosing sequence randomized (A/B or B/A). The washout period between the two doses was 1 week. Plasma concentrations over time were plotted and standard PK variables [area under the curve (AUC) of plasma concentration vs. time, maximum plasma concentration (C(max)), time to maximum plasma concentration (t(max)) and elimination half-life (t(1/2)] were determined. RESULTS: Drug exposure was markedly increased when alitretinoin was taken with food compared with fasting, and there were significant increases in mean C(max) (82.8 vs.25.4 ng/mL, respectively) and AUC (220.2 vs. 55.7 ng · h/mL). The delaying effect of food on t(max) was less marked (median of 3.0 vs. 2.0 h). Administration with food also increased exposure to drug metabolites. Variability in exposure was markedly reduced if alitretinoin was taken with vs. without food (percentage coefficient of variation 40% vs. 74% for AUC; 49% vs. 85% for C(max)). Alitretinoin was generally well tolerated, with typical retinoid adverse reactions, mostly comprising headache. CONCLUSIONS: Intake of alitretinoin with food substantially increased the bioavailability of alitretinoin, but variability in exposure was reduced. Consequently, oral alitretinoin should be taken with food as outlined in the manufacturer's summary of product characteristics.


Asunto(s)
Fármacos Dermatológicos/sangre , Interacciones Alimento-Droga , Tretinoina/sangre , Administración Oral , Adolescente , Adulto , Alitretinoína , Disponibilidad Biológica , Estudios Cruzados , Fármacos Dermatológicos/administración & dosificación , Fármacos Dermatológicos/efectos adversos , Ayuno/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tretinoina/administración & dosificación , Tretinoina/efectos adversos , Adulto Joven
7.
Clin Exp Dermatol ; 36 Suppl 2: 24-8, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21443601

RESUMEN

BACKGROUND: Based on in vitro data with isolated cytochrome P450 (CYP) isoenzymes, alitretinoin interacts only with CYP3A4, and the potential for drug-drug interactions is considered negligible. AIM: To confirm in humans the lack of potential interactions between CYP3A4 and alitretinoin in vivo. METHODS: This was a multiple-dose, open-label, parallel-group, single-centre study, which enrolled 54 healthy male volunteers aged 18-45 years. Subjects were divided into three groups, with 18 in each group: group 1 received either alitretinoin 30 mg and ketoconazole 200 mg, group 2 alitretinoin 30 mg and simvastatin 40 mg, and group 3 alitretinoin 30 mg and ciclosporin A 300-mg. RESULTS: At the highest therapeutic dose of 30 mg, alitretinoin had no significant effect on the pharmacokinetics (PK) of ketoconazole and ciclosporin A. There was a significant but not clinically relevant effect of simvastatin on the area under the curve (AUC) of plasma concentration vs. time and on maximum plasma concentration (C(max)) after repeated administration of alitretinoin. Exposure to simvastatin concomitantly with alitretinoin was decreased by 16% for AUC and 23% for C(max). The CYP3A4 ± PgP substrates of simvastatin and ciclosporin A did not affect the single or repeated dose PK of alitretinoin. The strong CYP3A4/PgP inhibitor ketoconazole led to significant increases in both AUC and C(max) values for alitretinoin. CONCLUSIONS: Single and repeated doses of alitretinoin do not alter the PK of ciclosporin A and ketoconazole. Simvastatin levels were slightly but significantly reduced by co-administration of alitretinoin. Substrates of CYP3A4 did not affect the PK of alitretinoin. However, ketoconazole significantly increased the plasma levels of alitretinoin, therefore, co-administration with CYP3A4 inhibitors such as ketoconazole may require a dose reduction of alitretinoin.


Asunto(s)
Ciclosporina/sangre , Fármacos Dermatológicos/farmacología , Cetoconazol/sangre , Simvastatina/sangre , Tretinoina/farmacología , Adolescente , Adulto , Alitretinoína , Antifúngicos/sangre , Estudios Cruzados , Fármacos Dermatológicos/administración & dosificación , Fármacos Dermatológicos/sangre , Esquema de Medicación , Interacciones Farmacológicas , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/sangre , Inmunosupresores/sangre , Masculino , Persona de Mediana Edad , Tretinoina/administración & dosificación , Tretinoina/sangre , Adulto Joven
8.
Clin Exp Dermatol ; 36 Suppl 2: 29-34, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21443602

RESUMEN

BACKGROUND: Recent studies have found that alitretinoin can induce clinically significant responses in subjects with severe chronic hand eczema (CHE) unresponsive to topical corticosteroids. AIMS: To assess the pharmacokinetics (PK), efficacy and safety of alitretinoin 10 or 30 mg once daily. METHODS: This was a randomized, double-blind study, which enrolled 32 subjects aged 18-75 years with CHE unresponsive to potent topical corticosteroids. Subjects received alitretinoin 10 mg (n = 16) or 30 mg (n = 16) once daily for 12 or 24 weeks. Standard PK variables [area under the curve (AUC) of plasma concentration vs. time, maximum plasma concentration (C(max)), time to maximum plasma concentration (t(max)), elimination half-life (t(1/2)), total systemic clearance (CL/F) and volume of distribution (Vd/F)] were determined for alitretinoin and metabolites. Efficacy was assessed using the Physician's Global Assessment (PGA) scale. RESULTS: Chronic administration of alitretinoin for up to 24 weeks did not result in accumulation or time-dependent changes in the disposition of alitretinoin. Exposure was found to be proportional to dose. Systemic exposure (AUC) to alitretinoin was proportional to dose for 10 and 30 mg alitretinoin; 62.8% of subjects achieved clear/almost clear hands in the 30 mg group and 12.5% in the 10 mg group. Alitretinoin was well tolerated. CONCLUSIONS: Chronic administration of alitretinoin for 12-24 weeks did not lead to accumulation or time-dependent changes in drug exposure. Alitretinoin was effective and well tolerated in the treatment of subjects with moderate or severe CHE unresponsive to potent topical corticosteroids.


Asunto(s)
Fármacos Dermatológicos/sangre , Dermatosis de la Mano/sangre , Tretinoina/sangre , Adolescente , Adulto , Anciano , Alitretinoína , Enfermedad Crónica , Fármacos Dermatológicos/efectos adversos , Fármacos Dermatológicos/uso terapéutico , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Femenino , Dermatosis de la Mano/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Tretinoina/efectos adversos , Tretinoina/uso terapéutico , Adulto Joven
10.
Inorg Chem ; 49(11): 5216-22, 2010 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-20426405

RESUMEN

Since the discovery of a formal quintuple bond in Ar'CrCrAr' (CrCr = 1.835 A) by Power and co-workers in 2005, many efforts have been dedicated to isolating dichromium species featuring quintuple-bond character. In the present study we investigate the electronic configuration of several, recently synthesized dichromium species with ligands using nitrogen to coordinate the metal centers. The bimetallic bond distances of Power's compound and Cr(2)-diazadiene (1) (CrCr = 1.803 A) are compared to those found for Cr(2)(mu-eta(2)-ArNC(R)NAr)(2) (2) (CrCr = 1.746 A; R = H, Ar = 2,6-Et(2)C(6)H(3)), Cr(2)(mu-eta(2)-Ar(Xyl)NC(H)NAr(Xyl))(3) (3) (CrCr = 1.740(reduced)/1.817(neutral) A; Ar(Xyl)= 2,6-C(6)H(3)-(CH(3))(2)), Cr(2)(mu-eta(2)-TippPyNMes)(2) (4) (CrCr = 1.749 A; TippPyNMes = 6-(2,4,6-triisopropylphenyl)pyridin-2-yl (2,4,6-trimethylphenyl)amide), and Cr(2)(mu-eta(2)-DippNC(NMe(2))N-Dipp)(2) (5) (CrCr = 1.729 A, Dipp = 2,6-i-Pr(2)C(6)H(3)). We show that the correlation between the CrCr bond length and the effective bond order (EBO) is strongly affected by the nature of the ligand, as well as by the steric hindrance due to the ligand structure (e.g., the nature of the coordinating nitrogen). A linear correlation between the EBO and CrCr bond distance is established within the same group of ligands. As a result, the CrCr species based on the amidinate, aminopyridinate, and guanidinate ligands have bond patterns similar to the Ar'CrCrAr' compound. Unlike these latter species, the dichromium diazadiene complex is characterized by a different bonding pattern involving Cr-Npi interactions, resulting in a lower bond order associated with the short metal-metal bond distance. In this case the short CrCr distance is most probably the result of the constraints imposed by the diazadiene ligand, implying a Cr(2)N(4) core with a closer CrCr interaction.

11.
Genes (Basel) ; 11(9)2020 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-32887425

RESUMEN

Dogs provide highly valuable models of human disease due to the similarity in phenotype presentation and the ease of genetic analysis. Seven Saluki puppies were investigated for neurological abnormalities including seizures and altered behavior. Magnetic resonance imaging showed a diffuse, marked reduction in cerebral cortical thickness, and symmetrical T2 hyperintensity in specific brain regions. Cerebral cortical atrophy with vacuolation (status spongiosus) was noted on necropsy. Genome-wide association study of 7 affected and 28 normal Salukis revealed a genome-wide significantly associated region on CFA 35. Whole-genome sequencing of three confirmed cases from three different litters revealed a homozygous missense variant within the aldehyde dehydrogenase 5 family member A1 (ALDH5A1) gene (XM_014110599.2: c.866G>A; XP_013966074.2: p.(Gly288Asp). ALDH5A1 encodes a succinic semialdehyde dehydrogenase (SSADH) enzyme critical in the gamma-aminobutyric acid neurotransmitter (GABA) metabolic pathway. Metabolic screening of affected dogs showed markedly elevated gamma-hydroxybutyric acid in serum, cerebrospinal fluid (CSF) and brain, and elevated succinate semialdehyde in urine, CSF and brain. SSADH activity in the brain of affected dogs was low. Affected Saluki dogs had striking similarities to SSADH deficiency in humans although hydroxybutyric aciduria was absent in affected dogs. ALDH5A1-related SSADH deficiency in Salukis provides a unique translational large animal model for the development of novel therapeutic strategies.


Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos/genética , Discapacidades del Desarrollo/genética , Mutación Missense/genética , Succionato-Semialdehído Deshidrogenasa/deficiencia , Succionato-Semialdehído Deshidrogenasa/genética , Secuencia de Aminoácidos , Animales , Encéfalo/metabolismo , Líquido Cefalorraquídeo/metabolismo , Modelos Animales de Enfermedad , Perros , Femenino , Pruebas Genéticas/métodos , Estudio de Asociación del Genoma Completo/métodos , Masculino , Redes y Vías Metabólicas/genética , Fenotipo , Convulsiones/genética , Convulsiones/metabolismo , Ácido gamma-Aminobutírico/genética
12.
Antimicrob Agents Chemother ; 53(11): 4885-90, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19667286

RESUMEN

Isavuconazole is a promising new antifungal drug with favorable pharmacokinetic properties and excellent activity against a number of fungi. It is administered as a water-soluble prodrug (BAL8557) that is cleaved by plasma esterases to isavuconazole, which is eliminated primarily by hepatic metabolism. The objective of this investigation was to assess the effect of alcohol-related liver disease on the pharmacokinetics of isavuconazole. Subjects were 16 healthy individuals, 16 with mild liver impairment, and 16 with moderate liver impairment who were randomized to receive a single oral or intravenous dose of BAL8557 equivalent to 100 mg isavuconazole. Blood samples were collected for 21 days following drug administration, and plasma concentrations of isavuconazole, BAL8557, and the cleavage product BAL8728 were measured using high-pressure liquid chromatography coupled with tandem mass spectrometry. Following intravenous administration, the half-life of isavuconazole increased from 123 h for healthy volunteers to 224 h and 302 h for subjects with mild and moderate liver impairment, respectively. The systemic clearance of isavuconazole following intravenous administration decreased from 2.73 liters/h for healthy subjects to 1.43 liters/h for subjects with moderate liver impairment (47.6% decrease [P < 0.05]). A similar decrease (23.5%) was observed after oral administration. These results suggest that a dose adjustment may be needed when isavuconazole is used to treat fungal infections in patients with liver disease.


Asunto(s)
Antifúngicos/farmacocinética , Hepatopatías/metabolismo , Nitrilos/farmacocinética , Profármacos/farmacocinética , Piridinas/farmacocinética , Triazoles/farmacocinética , Administración Oral , Área Bajo la Curva , Femenino , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Nitrilos/administración & dosificación , Piridinas/administración & dosificación , Triazoles/administración & dosificación
13.
South Afr J HIV Med ; 20(1): 1010, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31616576

RESUMEN

BACKGROUND: Chronic respiratory illnesses and respiratory infections are common in HIV-positive populations. It seems reasonable that HIV-positive people experience more respiratory symptoms, such as coughing and breathlessness, than those who are HIV-negative. OBJECTIVES: This study aims to determine the frequency of respiratory symptoms in an urban African HIV-positive population. METHOD: A cross-sectional study was conducted in Johannesburg, South Africa, in 2016-2017. Four groups of participants were included: HIV-positive participants (1) not yet on antiretroviral therapy (ART), (2) on first-line ART, (3) on second-line ART and (4) age- and sex-matched HIV-negative controls. Data were collected on socio-demographics, respiratory risk factors and respiratory symptoms. A logistic regression analysis was performed to determine if respiratory symptoms differed between groups and to identify determinants associated with symptoms. RESULTS: Overall, 547 participants were included, of whom 62% were women, with a median age of 37 years. Of these patients, 63% (347) were HIV-positive, 26% were ART-naïve, 24% were on first-line ART and 50% were on second-line ART. Cough and/or productive cough was reported by 27 (5%), wheezing by 9 (2%) and breathlessness by 118 (22%) of the participants. The frequency of these symptoms did not differ by HIV status after adjustment for age and sex. Breathlessness was associated with age, female sex, obesity, a history of respiratory infection and a history of airway hyper-reactivity. CONCLUSION: The frequency of respiratory symptoms was low in our study population except for breathlessness. HIV-positive participants, whether or not on ART, did not experience more symptoms than HIV-negative participants.

14.
J Clin Invest ; 83(5): 1580-9, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2565343

RESUMEN

Prosomatostatin (pro-S) and its bioactive posttranslational products, somatostatin-14 (S-14), somatostatin-13 (S-13), and somatostatin-28 (S-28), were measured in human plasma by the use of immunoglobulins to the NH2-terminus of S-28 conjugated with agarose to separate them and, thereafter, by RIA with an antiserum recognizing the COOH-terminus of pro-S, and by specific RIA for the NH2-terminus of S-14 and pro-S. In healthy men, mean basal levels of pro-S were 4 pg equivalent S-14/ml; S-14/S-13 combined were 9 pg equivalent S-14/ml; and S-28 levels were 16 pg/ml. After a 700-kcal meal, pro-S, S-14, and S-14/S-13 did not change, whereas S-28 levels doubled by 120 min and remained elevated for 240 min. To evaluate the origins of these peptides, their levels were compared in peripheral, portal, gastric, and mesenteric veins of anesthetized patients and in patients with total resection of stomach and pancreas before and after nutrient intake. The stomach and small intestine were sources of both peptides; however, most S-28 originated in the small intestine. These findings suggest that, in contrast to S-14, S-28 is a hormone and may modulate postprandial nutrient absorption and use.


Asunto(s)
Alimentos , Fragmentos de Péptidos/sangre , Precursores de Proteínas/sangre , Somatostatina/sangre , Adulto , Anciano , Secuencia de Aminoácidos , Brazo/irrigación sanguínea , Sitios de Unión de Anticuerpos , Femenino , Gastrectomía , Humanos , Sueros Inmunes , Masculino , Venas Mesentéricas , Persona de Mediana Edad , Pancreatectomía , Vena Porta , Precursores de Proteínas/inmunología , Somatostatina/inmunología , Estómago/irrigación sanguínea
15.
FASEB J ; 19(12): 1746-8, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16055499

RESUMEN

Conjugated linoleic acids (CLA) affect atherogenesis, but mechanisms are not well understood. We explored how two isomers of CLA, cis9, trans11-CLA and trans10, cis12-CLA, affected lipid and glucose metabolism, as well as hepatic protein expression, in apolipoprotein E knockout mice. After 12 wk of intervention, plasma triglyceride, NEFA, and glucose concentrations were significantly higher in the trans10, cis12-CLA group, whereas plasma triglyceride, NEFA, glucose, and insulin concentrations were significantly lower in the cis9, trans11-CLA group, compared with control mice consuming linoleic acid. Proteomics identified significant up- or down-regulation of 113 liver cytosolic proteins by either CLA isomer. Principal component analysis revealed that the treatment effect of cis9, trans11-CLA was mainly explained by the up-regulation of different posttranslational forms of heat shock protein 70 kD. In contrast, the treatment effect of trans10, cis12-CLA was mainly explained by up-regulation of key enzymes in the gluconeogenic, beta-oxidation, and ketogenesic pathways. Correlation analysis again emphasized the divergent effects of both CLA isomers on different pathways, but also revealed a linkage between insulin resistance and increased levels of hepatic serotransferrin. Thus, our systems biology approach provided novel insights into the mechanisms by which individual CLA isomers differentially affect pathways related to atherogenesis, such as insulin resistance and inflammation.


Asunto(s)
Apolipoproteínas E/genética , Ácido Linoleico/química , Ácidos Linoleicos Conjugados/metabolismo , Proteómica/métodos , Alimentación Animal , Animales , Aterosclerosis/patología , Glucemia/metabolismo , Western Blotting , Composición Corporal , Peso Corporal , Citosol/metabolismo , Dieta , Ácidos Grasos/metabolismo , Ligamiento Genético , Glucosa/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Inflamación , Insulina/metabolismo , Resistencia a la Insulina , Hígado/metabolismo , Masculino , Ratones , Ratones Noqueados , Oxígeno/metabolismo , Perfusión , Análisis de Componente Principal , Biología de Sistemas , Triglicéridos/metabolismo
16.
Cancer Res ; 40(11): 4192-6, 1980 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6110476

RESUMEN

We have recently reported the establishment of 16 series of calcitonin-producing transplantable rat medullary thyroid carcinoma. In the present study, these tumor series have been evaluated for the presence of somatostatin-like immunoreactivity. Each of the series contained detectable levels of both peptides. Immunoreactive somatostatin varied from less than 1 ng/mg of protein to almost 500 ng/mg of protein. The range of immunoreactive calcitonin was 0.3 to 30 micrograms/mg of protein. Although somatostatin-like immunoreactivity was always less than that of calcitonin, the levels in certain series were as high as those found in neural or endocrine tissues used for in vitro studies of somatostatin elaboration. No significant correlation was found between tissue levels of these two peptides. Two tumor lines were generated by initiation of tumor growth with cells from primary monolayer cultures. Levels of both immunoreactive calcitonin and somatostatin significantly differed from those of the parent lines, which were maintained by serial passage of tissue fragments only. Plasma somatostatin-like immunoreactivity assessed in two tumor series with high (149 ng/mg of protein) and low (1.5 ng/mg of protein) tissue levels was 3100 and 50 pg/ml, respectively. Gel filtration chromatography of tissue and blood extracts showed a predominant peak (greater than 90%) of immunoreactive somatostatin eluting at the position of the native hormone. Three other peaks were resolved in the tissue extract with estimated molecular weights of 14,000, 8,700, and 5,000. The high level of somatostatin-like immunoreactivity and the presence of multiple large forms suggest that certain tumor lines will prove valuable for studies of somatostatin biosynthesis and secretion.


Asunto(s)
Calcitonina/metabolismo , Carcinoma/metabolismo , Somatostatina/metabolismo , Neoplasias de la Tiroides/metabolismo , Animales , Neoplasias Experimentales/metabolismo , Radioinmunoensayo , Ratas , Somatostatina/biosíntesis , Somatostatina/sangre , Somatostatina/inmunología
17.
Cancer Res ; 49(24 Pt 1): 6949-52, 1989 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-2582437

RESUMEN

The ratios of calcitonin (CT) to calcitonin gene-related peptide (CGRP) mRNA, both generated by alternative RNA processing from the same primary RNA transcript, are shown by Northern blotting of cytoplasmic RNA to vary as a function of growth in a human medullary thyroid carcinoma cell line (TT). Upon initial seeding, CT mRNA levels are relatively high, and CGRP mRNA levels are relatively low. During the early logarithmic growth phase, CGRP mRNA levels rise severalfold, while CT mRNA levels change only slightly. As the cells approach confluence, both CT and CGRP mRNA levels rise. Subsequently, CGRP mRNA levels fall substantially in postconfluent cells, while CT mRNA levels remain high. By actinomycin D blocking of nascent transcription, we have shown that these growth-related, reversible changes in the ratio of CT to CGRP mRNA are not due to changes in mRNA stability. Our data rather suggest that TT cells reversibly alter alternative RNA-processing patterns dependent upon growth conditions in vitro, such that CT mRNA is lowest and CGRP mRNA is highest during rapid growth. The mechanisms underlying this RNA-processing alteration may play a role in certain patients with aggressive forms of medullary thyroid carcinoma, in whom a decrease or loss of CT levels heralds a poor prognosis.


Asunto(s)
Calcitonina/genética , Carcinoma/genética , Procesamiento Postranscripcional del ARN , Neoplasias de la Tiroides/genética , Northern Blotting , Péptido Relacionado con Gen de Calcitonina/genética , Carcinoma/patología , Expresión Génica , Semivida , Humanos , Hibridación de Ácido Nucleico , ARN Mensajero/genética , Neoplasias de la Tiroides/patología , Células Tumorales Cultivadas
18.
Cancer Res ; 57(5): 900-6, 1997 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-9041192

RESUMEN

We previously reported that a transgenic mouse line containing the fetal globin promoter linked to the SV40 T antigen (T Ag) viral oncogene (Ggamma/T-15) resulted in prostate tumors. In this study, we further explored tumor origin, frequency, invasiveness, androgen sensitivity, and gene expression pattern. T Ag was detected in adult but not fetal and neonatal prostates, suggesting a role for androgens in tumor progression. However, castration shortly after prostate morphogenesis did not prevent tumor development, suggesting an androgen-independent phenotype. Tumors originated within ventral or dorsal prostate lobes and involved intraepithelial neoplasia, rapid growth in the pelvic region, and metastasis to lymph nodes and distant sites. In addition, the primary cancers could be propagated in nude mice or nontransgenic mice. Seventy-five percent of hemizygous and 100% of homozygous transgenic males developed prostate tumors, suggesting a T Ag dosage effect. Biochemical characterization of advanced tumors revealed markers of both neuroendocrine and epithelial phenotypes; markers of terminal differentiation are lost early in tumorigenesis. Tumor suppressor genes (p53 and Rb), normally bound to T Ag, were up-regulated; bcl-2 proto-oncogene, which prevents apoptosis, was slightly up-regulated. Myc, a stimulus to cell cycle progression, was unchanged. We propose the Ggamma/T-15 transgenic line as a model of highly aggressive androgen-independent metastatic prostate carcinoma with features similar to end-stage prostate cancer in humans.


Asunto(s)
Adenocarcinoma/patología , Neoplasias de la Próstata/patología , Adenocarcinoma/genética , Andrógenos/fisiología , Animales , Antígenos Transformadores de Poliomavirus/genética , Cromogranina A , Cromograninas/metabolismo , Regulación del Desarrollo de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Genes de Retinoblastoma , Genes bcl-2 , Genes myc , Genes p53 , Queratinas/metabolismo , Masculino , Ratones , Ratones Transgénicos , Metástasis de la Neoplasia , Orquiectomía , Lesiones Precancerosas/patología , Neoplasias de la Próstata/genética , Proto-Oncogenes Mas , ARN Mensajero/genética , Factores de Tiempo
19.
J Mol Biol ; 261(4): 586-96, 1996 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-8794878

RESUMEN

The geometry of several realistic models of the metal coordination sphere in the blue copper proteins has been optimised using high-level quantum chemical methods. The results show that the optimal vacuum structure of the Cu(II) models is virtually identical to the crystal structure of oxidised blue copper proteins. For the reduced forms, the optimised structure seems to be more tetrahedral than the one found in the proteins, but the energy difference between the two geometries is less than 5 kJ/mol, i.e. within the error limits of the method. Thus, the results raise strong doubts against hypotheses (entatic state and the induced-rack theory) suggesting that blue copper proteins force the oxidised metal coordination sphere into a structure similar to that preferred by Cu(I) in order to minimise the reorganisation energy of the electron transfer reaction. Instead, a small reorganisation energy seems to be reached by an appropriate choice of metal ligands. In particular, the cysteine thiolate ligand appears to be crucial, changing the preferred geometry of the oxidised complexes from square-planar to a more trigonal geometry.


Asunto(s)
Proteínas Bacterianas/química , Cobre/química , Modelos Moleculares , Ligandos , Oxidación-Reducción , Conformación Proteica , Teoría Cuántica , Vacio
20.
Arch Gen Psychiatry ; 33(4): 501-5, 1976 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-779704

RESUMEN

Four patients with chronic schizophrenia of stationary character were studied in order to titrate the lowest dose of thioridazine necessary for symptomatic control when the drug is given in combination with the inhibitor of catecholamine synthesis, metyrosine. The study showed 15% to 50% of the pretrial dose level of thioridazine hydrochloride was effective. In the present trial, the 779704 combination was maintained without any alterations in dosage for six months, and the therapeutic effect persisted unchanged. This treatment period was terminated by a double-blind crossover design, and the activity of metyrosine was corroborated in all cases. Plasma drug concentrations and cerebrospinal fluid amine metabolites were measured. The data indicate that schizophrenic symptoms can be profoundly influenced by changes in catecholamine synthesis. Catecholamine-carrying neurons thus seem to be fundamentally involved in those brain functions that are disturbed in schizophrenia. The clinical usefulness of metyrosine in combination with neuroleptic agents deserves more extensive investigation.


Asunto(s)
Metiltirosinas/administración & dosificación , Esquizofrenia/tratamiento farmacológico , Tioridazina/administración & dosificación , Anciano , Enfermedad Crónica , Ensayos Clínicos como Asunto , Sinergismo Farmacológico , Quimioterapia Combinada , Femenino , Ácido Homovanílico/líquido cefalorraquídeo , Humanos , Ácido Hidroxiindolacético/líquido cefalorraquídeo , Masculino , Metiltirosinas/uso terapéutico , Persona de Mediana Edad , Esquizofrenia/líquido cefalorraquídeo , Tioridazina/uso terapéutico
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