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1.
J Endocrinol Invest ; 43(6): 779-786, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31845191

RESUMEN

PURPOSE: Fasting blood homocysteine is increased in PCOS women and is involved in several of its co-morbidities including cardiovascular disease and infertility. Corrective interventions based on the administration of supra-physiologic doses of folic acid work to a low extent. We aimed to test an alternative approach. METHODS: This was a prospective, randomized, parallel group, open label, controlled versus no treatment clinical study. PCOS women aged > 18, free from systemic diseases and from pharmacological treatments were randomized with a 2:1 ratio for treatment with activated micronutrients in support to the carbon cycle (Impryl, Parthenogen, Switzerland-n = 22) or no treatment (n = 10) and followed-up for 3 months. Fasting blood homocysteine, AMH, testosterone, SHBGs, and the resulting FTI were tested before and at the end of the follow-up. RESULTS: The mean baseline fasting blood homocysteine was above the normal limit of 12 µMol/L and inversely correlated with SHBG. AMH was also increased, whereas testosterone, SHBG, and FTI were within the normal limit. The treatment achieved a significant reduction of homocysteine, that did not change in the control group, independently of the starting value. The treatment also caused an increase of AMH and a decrease of SHBGs only in the subgroup with a normal homocysteine at baseline. CONCLUSIONS: In PCOS ladies, blood homocysteine is increased and inversely correlated with the SHBGs. Physiologic amounts of activated micronutrients in support to the carbon cycle achieve a reduction virtually in all exposed patients. Whether this is of clinical benefit remains to be established.


Asunto(s)
Ciclo del Carbono/fisiología , Ayuno/sangre , Homocisteína/sangre , Micronutrientes/administración & dosificación , Síndrome del Ovario Poliquístico/sangre , Síndrome del Ovario Poliquístico/dietoterapia , Adulto , Biomarcadores/sangre , Femenino , Estudios de Seguimiento , Humanos , Síndrome del Ovario Poliquístico/diagnóstico , Estudios Prospectivos , Adulto Joven
2.
Sci Rep ; 8(1): 11769, 2018 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-30082742

RESUMEN

The sperm plasma membrane is a sensitive target to oxidative stress. The most representative reactive oxygen species (ROS) scavengers in the genital tract, hypotaurine and glutathione, require, for their synthesis, cysteine whose availability is associated with the 1-carbon cycle (1-CC). Human, bovine and ascidian spermatozoa were incubated with compounds supporting the 1-CC (Vitamin B6, Methylcobalamin, 5 Methyl Tetrahydrofolate, Zinc Bisglycinate and N-acetyl-cysteine) (TRT) and compared to the effects induced solely by N-acetyl-cysteine (NAC). In control groups (CNTRL), spermatozoa were incubated with medium alone. After 90 and 180 minutes of incubation, the mitochondrial membrane potential (ΔΨM) in TRT and NAC was significantly (P < 0.01) higher than in CNTRL. At H2DCFDA evaluation, ROS production differed between species whereas, at 2-OH Ethidium, it significantly decreased in bovine TRT group. Intracellular pH (pHi) did not significantly vary in relation to treatment. In ascidian spermatozoa, the NAC supplementation decreased external pH, which in turn brought to a pHi lowering. Buffering seawater with NaHCO3 reversed the beneficial effects of N-acetyl-cysteine supplementation. In conclusion, both fully supporting the 1-CC and treatment with N-acetyl-cysteine alone improved kinetics, ΔΨM and ROS production in mammalian sperm demonstrating for the first time the direct in vitro effects of these compounds on sperm functionality.


Asunto(s)
Carbono/metabolismo , Motilidad Espermática/fisiología , Espermatozoides/metabolismo , Espermatozoides/fisiología , Animales , Bovinos , Humanos , Concentración de Iones de Hidrógeno , Peroxidación de Lípido/fisiología , Masculino , Potencial de la Membrana Mitocondrial/fisiología , Estrés Oxidativo/fisiología , Especies Reactivas de Oxígeno/metabolismo , Urocordados
3.
Handb Clin Neurol ; 139: 329-341, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27719853

RESUMEN

Nonorganic visual loss (NOVL) is the cause of a large number of referrals to neurologists and ophthalmologists and is a frequent area of overlap between neurologists, ophthalmologists, and psychiatrists. NOVL is the presence of visual impairment without an organic cause for disease despite a thorough and comprehensive investigation. A diagnosis of NOVL requires both the absence of any findings on examination and proof of the integrity and functioning of the visual system. Although sometimes a challenging diagnosis to make, there are a number of techniques and maneuvers which can be utilized fairly easily, either at the bedside or in the clinic, to help determine if a patient has NOVL. In some instances specialized testing, such as formal visual field testing, optical coherence tomography, visual evoked responses, electroretinogram, and various imaging modalities (magnetic resonance imaging) are performed to help determine if the cause of visual loss is organic or nonorganic. Once a diagnosis of NOVL is made, treatment centers around reassurance of the patient, close follow-up, and, if necessary, referral to a psychiatrist, as these patients may have underlying psychiatric disorders and a preceding strong emotional event leading to the current symptoms, and may be more likely to develop depression and anxiety.


Asunto(s)
Trastornos Somatomorfos , Trastornos de la Visión/psicología , Humanos
4.
Med Hypotheses ; 80(6): 701-5, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23490203

RESUMEN

Sleep is important for maintenance of skeletal muscle health. Sleep debt can induce muscle atrophy by increasing glucocorticoids and decreasing testosterone, growth hormone and insulin-like growth factor-I. These hormonal alterations result in a highly proteolytic environment characterized by decreased protein synthesis and increased degradation. Given that sleep deprivation is increasingly prevalent in modern society, strategies to minimize or reverse its adverse effects need to be investigated. Resistance exercise has been suggested as an intervention that would benefit the muscle health. The practice of this type of exercise can increase the concentration of testosterone, growth hormone and insulin-like growth factor I and stimulate the protein synthesis through a key signaling molecule, mammalian target of rapamycin. Thus, we hypothesized that resistance exercise is an important non-pharmacological strategy to counteract deleterious effects of sleep debt on skeletal muscle.


Asunto(s)
Atrofia Muscular/etiología , Atrofia Muscular/prevención & control , Entrenamiento de Fuerza/métodos , Privación de Sueño/complicaciones , Humanos , Modelos Biológicos , Biosíntesis de Proteínas/fisiología , Proteolisis
5.
Med Hypotheses ; 77(2): 220-2, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21550729

RESUMEN

Sleep is essential for the cellular, organic and systemic functions of an organism, with its absence being potentially harmful to health and changing feeding behavior, glucose regulation, blood pressure, cognitive processes and some hormonal axes. Among the hormonal changes, there is an increase in cortisol (humans) and corticosterone (rats) secretion, and a reduction in testosterone and Insulin-like Growth Factor 1, favoring the establishment of a highly proteolytic environment. Consequently, we hypothesized that sleep debt decreases the activity of protein synthesis pathways and increases the activity of degradation pathways, favoring the loss of muscle mass and thus hindering muscle recovery after damage induced by exercise, injuries and certain conditions associated with muscle atrophy, such as sarcopenia and cachexia.


Asunto(s)
Trastornos Musculares Atróficos/etiología , Biosíntesis de Proteínas/fisiología , Proteolisis , Recuperación de la Función/fisiología , Privación de Sueño/complicaciones , Privación de Sueño/metabolismo , Animales , Humanos , Hidrocortisona/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Ratas , Testosterona/metabolismo
6.
J Surg Res ; 77(1): 35-9, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9698529

RESUMEN

Ultrastructural studies of stunned myocardium have shown disorganization and loss of extracellular collagen and increased collagenase activity early after ischemia and reperfusion. The interplay between matrix metalloproteinase 1 (MMP-1) and tissue inhibitor of metalloproteinase 1 (TIMP-1) regulates the turnover of cardiac extracellular matrix fibrillar collagens. However, the gene expression of MMP-1 and TIMP-1 in stunned myocardium is not known. Here, we determined whether altered expression of MMP-1 and TIMP-1 occurs in globally stunned hearts. An isolated nonworking rabbit heart preparation, perfused with a bovine erythrocyte suspension in modified Krebs solution, was used. Two groups were studied: the stunned group was subjected to 20 min of normothermic global ischemia followed by 120 min of normal reperfusion (n = 8), and the control group underwent 140 min of uninterrupted perfusion (n = 7). The developed pressures at the end of reperfusion for ischemic and control hearts were 67.0 +/- 2.73 and 83.1 +/- 1.52 mm Hg (P < 0. 006) respectively. Ribonuclease protection assays of total left ventricular RNA using riboprobes for MMP-1, TIMP-1, and 18S rRNA were performed. A significant decrease (twofold, P < 0.03) in TIMP-1 gene expression was found in the stunned hearts, while MMP-1 mRNA expression was unchanged. Thus, in early stunning, the decrease in TIMP-1 expression could tip the balance favoring enhanced metalloproteinase activity, promoting collagen turnover, and initiating extracellular matrix remodeling. This may contribute to delayed recovery from myocardial stunning.


Asunto(s)
Aturdimiento Miocárdico/metabolismo , Miocardio/metabolismo , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Animales , Presión Sanguínea/fisiología , Bovinos , Colagenasas/genética , Colagenasas/metabolismo , Diástole , Expresión Génica/fisiología , Técnicas In Vitro , Metaloproteinasa 1 de la Matriz , Hibridación de Ácido Nucleico , ARN Mensajero/metabolismo , ARN Ribosómico 18S/metabolismo , Conejos , Ribonucleasas , Inhibidor Tisular de Metaloproteinasa-1/genética
7.
J Surg Res ; 74(1): 39-42, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9536971

RESUMEN

BACKGROUND: The success of vascular bypass procedures is limited by the development of intimal hyperplasia (IH). The nitric oxide (NO) precursor, L-arginine (L-ARG) significantly reduces IH in both arteries and experimental vein grafts; however, the precise mechanism has yet to be elucidated. Hyaluronan synthase-1 (HAS-1) is one of the two enzymes believed to be responsible for making hyaluronan, a key component extracellular matrix composition. PURPOSE: To determine how L-ARG supplementation affects the gene expression of HAS-1 in experimental vein grafts. METHODS: Thirty-four male New Zealand white rabbits were divided into three groups: control (no operation, regular chow and water, n = 4); L-ARG supplemented (n = 15); and no L-ARG (n = 15). The latter two groups underwent a right interposition carotid bypass using jugular vein. Vein grafts were harvested at 7, 14, and 21 days after surgery. Ribonuclease protection assays were performed using 32P-labeled riboprobes for HAS-1 and 18S rRNA as an internal control and expressed as a ratio (HAS-1/rRNA). RESULTS: There was a significant rise in HAS-1 expression in the vein grafts 7 (1.57 +/- 0.5), 14 (0.7 +/- 0.2), and 21 days (2.82 +/- 0.7) after grafting compared to control (0.14 +/- 0.08) (P < 0.05). L-ARG-supplemented animals had a significant decrease in HAS-1 expression at 21 days (0.65 +/- 0.1) compared to nonsupplemented vein grafts (2.82 +/- 0.7) (P < 0.02). CONCLUSIONS: These results demonstrate for the first time a significant rise in HAS expression in the early experimental vein grafts. Furthermore, L-ARG supplementation significantly diminishes the expression of HAS at 21 days. These results may represent a potential mechanism by which augmentation of the L-ARG/NO pathway inhibits IH in experimental vein grafts and may ultimately provide for improved therapeutic interventions in alleviating IH.


Asunto(s)
Arginina/farmacología , Glucuronosiltransferasa/genética , Glicosiltransferasas , Isoenzimas/genética , Venas Yugulares/efectos de los fármacos , Venas Yugulares/cirugía , Proteínas de la Membrana , Óxido Nítrico/metabolismo , Transferasas , Proteínas de Xenopus , Animales , Arginina/metabolismo , Arterias Carótidas/cirugía , Expresión Génica/efectos de los fármacos , Hialuronano Sintasas , Hiperplasia/etiología , Hiperplasia/patología , Hiperplasia/prevención & control , Venas Yugulares/metabolismo , Masculino , ARN Mensajero/genética , ARN Mensajero/metabolismo , Conejos , Procedimientos Quirúrgicos Vasculares
8.
Ann Vasc Surg ; 12(2): 168-73, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9514237

RESUMEN

The success rate of vascular bypass procedures is limited by the development of intimal hyperplasia (IH). Hypercholesterolemia has been shown to accelerate IH in both arteries and experimental vein grafts; however the mechanism remains uncertain. Hyaluronic acid synthase (HAS-1) is a transmembrane enzyme responsible for the formation of hyaluronan; an important constituent of extracellular matrix (ECM). The integrin receptor for hyaluronan is CD-44. Both CD-44 and HAS-1 have been studied in the development of ECM of wounds but have yet to be examined in the ECM of IH within vein grafts. The purpose of this study was to determine if the expression of CD-44 and HAS-1 is increased during the early stages of IH and how cholesterol supplementation affects these genes. Forty white male New Zealand rabbits were divided into two groups: cholesterol supplemented (1% cholesterol chow) and noncholesterol supplemented. Each set of 20 rabbits was then divided into four additional groups (n = 5); a nonoperative group (control) and three operative groups that underwent a right interposition carotid bypass using jugular vein. Grafts were harvested at 3, 7, and 21 days after surgery for molecular studies and histology. Ribonuclease protection assays were performed using 32P-labeled riboprobes for HAS-1, CD-44, and 18s rRNA. Densitometric analysis is expressed as a ratio (riboprobe/rRNA). Cholesterol levels differed significantly between cholesterol supplemented and nonsupplemented groups (1419 +/- 130 mg/dl and 48 +/- 12 mg/dl) (p < 0.01). There was a significant increase in the expression of HAS-1 and CD-44 in the vein grafts compared to normal jugular vein. Cholesterol supplementation caused a further increase in CD-44 gene expression versus nonsupplemented vein grafts. These data demonstrate a role for CD-44 and HAS-1 transcription in vein graft intimal hyperplasia, which is further altered by cholesterol supplementation. Lastly, these results could explain differences seen in the development of IH with hypercholesterolemia and ultimately provide for improved therapies in alleviating this process.


Asunto(s)
Matriz Extracelular/genética , Glucuronosiltransferasa/genética , Glicosiltransferasas , Receptores de Hialuranos/genética , Hipercolesterolemia/genética , Proteínas de la Membrana , Transferasas , Venas/trasplante , Proteínas de Xenopus , Animales , Colesterol en la Dieta/farmacología , Matriz Extracelular/química , Expresión Génica , Glucuronosiltransferasa/análisis , Hialuronano Sintasas , Hiperplasia , Masculino , Conejos , Túnica Íntima/patología , Venas/patología
9.
J Clin Gastroenterol ; 27 Suppl 1: S163-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9872516

RESUMEN

The proton pump inhibitors (PPIs) omeprazole, lansoprazole, and pantoprazole are widely used as antisecretory drugs and, in association with antibiotics, for the treatment of Helicobacter pylori infections. PPIs possess antibacterial activity against H. pylori in vitro, and may also exert an anti-inflammatory effect by interfering with the cellular immune response to infection. Their antimicrobial activity is selective for H. pylori. Lansoprazole is the most effective, although its bactericidal activity is similar to that of omeprazole. Pantoprazole is the least effective. The mechanisms that account for the antibacterial effects of PPIs may depend on a structural similarity of PPIs to antibiotics which are active against H. pylori, on the inhibition of bacterial urease exerted by PPIs, or on the possible interaction of PPIs with bacterial ATPases that regulate the transmembrane ion flux. Recent studies have shown that PPIs have anti-inflammatory actions and can interfere with the host-bacteria interactions. Lansoprazole can bind to polymorphonuclear leukocytes that infiltrate the gastric mucosa colonized by H. pylori and can thus inhibit the oxidative burst of activated inflammatory cells. In an in vivo study, lansoprazole reduced the degree of activity of histologic gastritis independently of the presence of H. pylori. In another study, omeprazole was capable of inhibiting the cytotoxic activity of NK T cells. Investigation of PPI interactions with H. pylori activities and the cellular immune response to the infection may help us to understand the pathogenic mechanisms of H. pylori-associated diseases and enable clinicians to better treat them.


Asunto(s)
Antibacterianos/uso terapéutico , Antiulcerosos/uso terapéutico , Gastritis/tratamiento farmacológico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Inhibidores de la Bomba de Protones , 2-Piridinilmetilsulfinilbencimidazoles , Bencimidazoles/uso terapéutico , Enfermedad Crónica , Humanos , Lansoprazol , Omeprazol/análogos & derivados , Omeprazol/uso terapéutico , Pantoprazol , Sulfóxidos/uso terapéutico
10.
Am J Surg ; 174(2): 177-80, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9293839

RESUMEN

BACKGROUND: The patency of vascular reconstructive procedures is limited by the development of intimal hyperplasia (IH). Nitric oxide (NO) seems to be beneficial in abrogating this process. Currently, there is little information concerning inducible nitric oxide synthase (iNOS), the enzyme responsible for NO synthesis, and human vein grafts. The purpose of this study was to examine iNOS gene expression in human aortocoronary vein grafts (ACVG) and infrainguinal vein bypass grafts (IVG). METHODS: Nonthrombosed sections from ACVG (n = 5), IVG (n = 5), and control saphenous vein (SV; n = 4) were harvested and processed for RNA isolation. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) was performed on samples using 32P radioactively end labeled primers. Glyceraldehyde-3-phosphate-dehydrogenase (GAPDH) was the internal control, and results were expressed as iNOS pmol/GAPDH pmol. RESULTS: There was a significant increase in the iNOS gene expression in the ACVG (0.049 +/- 0.01) when compared with IVG (0.019 +/- 0.001) or normal SV (0.011 +/- 0.002; P < or = 0.05). There was no significant difference between normal vein and the infrainguinal grafts. Sequencing of a fragment of the amplified 428 bp gene product confirmed 84% homology with the available gene bank human sequence. CONCLUSIONS: This study proves that iNOS is expressed in human vein bypass grafts. Additionally, there is a significant elevation of iNOS message in human ACVGs compared with IVG or normal SV. This difference may be the result of the unique vascular beds supplied by these grafts. Ultimately, manipulation of iNOS expression may lead to therapies to alleviate IH in these grafts.


Asunto(s)
Puente de Arteria Coronaria , Regulación Enzimológica de la Expresión Génica , Pierna/irrigación sanguínea , Óxido Nítrico Sintasa/biosíntesis , Homología de Secuencia , Venas/enzimología , Venas/trasplante , Arteriopatías Oclusivas/cirugía , Secuencia de Bases , Enfermedad Coronaria/cirugía , Activación Enzimática , Humanos , Datos de Secuencia Molecular , Óxido Nítrico Sintasa/química , Reacción en Cadena de la Polimerasa/métodos , Transcripción Genética
11.
Ital J Gastroenterol Hepatol ; 29(4): 312-9, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9476183

RESUMEN

BACKGROUND/AIMS: The efficacy of proton pump inhibitors is considered linked to morning, fasting administration. The aim of the present study was to assess efficacy and tolerability of the proton pump inhibitors lansoprazole given at bedtime as compared to ranitidine, both in acute and maintenance treatment of duodenal ulcer. METHODS: This was a randomised double blind study. The patients were divided into 4 treatment groups as follows (healing/maintenance): 1) lansoprazole 30 mg/lansoprazole 15 mg; 2) lansoprazole 30 mg/placebo; 3) ranitidine 300 mg/ranitidine 150 mg; 4) ranitidine 300 mg/placebo. Healing and relapse of ulcers were assessed by endoscopy at 2, 4 and 8 weeks and then at 3, 6, 9 and 12 months during follow-up. RESULTS: A total of 132 patients were enrolled in 9 study centres. The cumulative healing rates (per-protocol analysis) at 2, 4 and 8 weeks were 57.4%, 83.9% and 89.2% in the lansoprazole group and 30%, 70.2% and 78.7% in the ranitidine group (p = 0.01 at 2 weeks). The 12-month cumulative relapse rate (intent-to-treat analysis) was lower in the lansoprazole/lansoprazole group (23.3%), than those reported by the other groups of patients lansoprazole/placebo (39.3%); ranitidine/ranitidine (45.8%); ranitidine/placebo (50%). The disease-free time from healing was significantly longer for lansoprazole treated patients (p < 0.05). All treatments were very well tolerated, only few minor adverse events being reported. CONCLUSIONS: Lansoprazole maintains its greater efficacy vs ranitidine even when administered at bedtime, both for the healing and for the maintenance treatment of duodenal ulcer. Lansoprazole (half dose formulation) may be useful for the treatment of patients requiring long-term acid suppression.


Asunto(s)
Antiulcerosos/administración & dosificación , Úlcera Duodenal/tratamiento farmacológico , Omeprazol/análogos & derivados , Inhibidores de la Bomba de Protones , Ranitidina/administración & dosificación , 2-Piridinilmetilsulfinilbencimidazoles , Adolescente , Adulto , Anciano , Antiulcerosos/uso terapéutico , Reposo en Cama , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Úlcera Duodenal/metabolismo , Úlcera Duodenal/patología , Endoscopía del Sistema Digestivo , Femenino , Estudios de Seguimiento , Humanos , Lansoprazol , Masculino , Persona de Mediana Edad , Omeprazol/administración & dosificación , Omeprazol/uso terapéutico , Ranitidina/uso terapéutico , Recurrencia , Resultado del Tratamiento
12.
J Fla Med Assoc ; 84(5): 316-9, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9260436

RESUMEN

OBJECTIVE: To determine the efficacy and cost of a simplified superovulation regimen compared with traditional control ovarian hyperstimulation with gonadotropins (HMG). STUDY DESIGN: This was a retrospective study in a university referral center with 99 infertile couples undergoing 225 treatment cycles. The outcome was compared to outcomes of previously published studies. The simplified superovulation regimen included clomiphene citrate 100 mg on cycle days 5 through 9 and HMG 75 IU on cycle days 5, 7, 9, and 11, with estradiol and ultrasound monitoring on day 13. If adequate follicular maturity was documented, HCG 10,000 IU was administered, followed by intrauterine insemination 40 hours later. RESULTS: Fecundity rates were assessed by life table analysis. Average cycle fecundity was 8%, with a cumulative rate of 29% over 4 cycles, compared to 10% monthly fecundity with HMG/IUI and background rates of 1 to 3%. Costs averaged $662 per cycle compared to $1,854 with HMG/IUI. CONCLUSION: A simplified protocol of CC/HMG/ IUI is almost as effective as HMG/IUI and costs only one-third as much.


Asunto(s)
Infertilidad/tratamiento farmacológico , Inseminación Artificial/economía , Superovulación , Adulto , Protocolos Clínicos , Clomifeno/uso terapéutico , Análisis Costo-Beneficio , Femenino , Fertilidad , Fármacos para la Fertilidad Femenina/uso terapéutico , Humanos , Infertilidad/etiología , Inseminación Artificial/métodos , Masculino , Menotropinas/uso terapéutico , Embarazo , Índice de Embarazo , Estudios Retrospectivos
13.
J Antimicrob Chemother ; 39(5): 585-90, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9184356

RESUMEN

Lansoprazole is a gastric parietal cell proton pump inhibitor that is also active against Helicobacter pylori in vitro. We aimed to investigate further the mechanism of its antimicrobial effect. The antimicrobial activity of lansoprazole and of its sulfenamide, a rearrangement product occurring spontaneously in acid environments, was studied by determining the MICs and MBCs for 11 cytotoxic and eight non-cytotoxic H. pylori strains and by measuring the rapidity of bacterial killing. The MIC90 and MBC90 were 2.5 mg/L and 10 mg/L, respectively, both for lansoprazole and for its sulfenamide. Cytotoxic strains were as susceptible as non-cytotoxic strains. The sulfenamide exhibited faster bactericidal activity. Lansoprazole did not inhibit the toxin-induced vacuolization of HeLa cells by a cytotoxic strain, hence its anti-H. pylori activity does not depend on inhibition of a v-ATPase-mediated, toxin-induced activity. Sulfenamide formation is likely to occur in vivo in the gastric environment, thus enhancing the bactericidal activity of the drug. Lansoprazole is likely to be useful, in association with antibiotics, in the treatment of H. pylori infection regardless of the cytotoxicity of the infecting strain.


Asunto(s)
Antibacterianos/farmacología , Helicobacter pylori/efectos de los fármacos , Omeprazol/análogos & derivados , Inhibidores de la Bomba de Protones , 2-Piridinilmetilsulfinilbencimidazoles , Lansoprazol , Pruebas de Sensibilidad Microbiana , Omeprazol/farmacología , Vacuolas/efectos de los fármacos
14.
J Surg Res ; 69(2): 349-53, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9224405

RESUMEN

The success of coronary reconstructive procedures is limited by the high incidence of restenosis secondary to intimal hyperplasia (IH). Transforming growth factor-beta 1 (TGF-beta 1) is a growth factor which has been shown to be important in the early development of IH in arteries and peripheral vein grafts. To date, there is little information concerning the early remodeling in aortocoronary vein grafts (ACVG). The purpose of this study was to characterize the expression of TGF-beta 1 expression in early aortocoronary vein grafts. Eighteen mongrel dogs underwent aortocoronary vein bypass grafting. Vein grafts were excised at 2 hr, 4 hr, and 7 days after implantation, snap frozen, and processed for ribonuclease protection assays (RPA) using 32P-labeled riboprobes for TGF-beta 1 and 18 S rRNA. TGF-beta 1 expression was quantified by densitometric analysis of autoradiographs which were expressed as a ratio TGF-beta 1/rRNA. Representative vessel rings were also collected for histology. There was a significant rise in TGF-beta 1 expression in the 2-hr vein grafts (0.42 +/- 0.04 compared to control saphenous vein (0.21 +/- 0.05, P < 0.02). In addition, there was significant downregulation of TGF-beta 1 at 4 hr (0.28 +/- 0.05) and at 7 days (0.18 +/- 0.01) when compared to 2 hr (P < 0.05). Histological specimens showed minimal intimal hyperplasia at 7 days. These results show for the first time an acute rise in TGF-beta 1 expression in ACVG. This upregulation quickly subsides by 4 hr and gene expression approaches control values by 7 days. By understanding this temporal relationship of expression one could better target potential therapeutic modalities to attenuate IH.


Asunto(s)
Puente de Arteria Coronaria , Factor de Crecimiento Transformador beta/metabolismo , Venas/metabolismo , Animales , Circulación Coronaria , Perros , Hiperplasia , Vena Safena , Factores de Tiempo , Túnica Íntima/patología
15.
Transplantation ; 63(2): 310-4, 1997 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-9020336

RESUMEN

The induction of transplantation tolerance is one of the primary goals following solid organ transplantation. The combination of a single dose of rapamycin (RAPA) with a short course of cyclosporine (CsA) has been shown to induce transplantation tolerance in the nonfunctional rat heterotopic cardiac transplant model. The purpose of this study was to assess this effective induction protocol in a functional renal transplant model. Male ACI (RTl(a)) and Lewis (RT1(1)) rats were used as donor and recipients respectively. Allografts received a single RAPA dose of (1.5 mg/kg) combined with CsA (10 mg/kg) 12-14 hr prior to transplantation. CsA (5 mg/kg) was given daily on days +1 - +7. Untreated Lewis to Lewis isografts served as histological controls. Chimerism, assessed in recipient skin, and intragraft interleukin (IL) 10 expression was determined utilizing PCR and RT-PCR techniques respectively. Treated animals and isografts were sacrificed 120-130 days posttransplant for functional and histological evaluation. Allografts (n=9) were functionally tolerant with serum creatinine (0.77+/-0.1 vs. 0.88+/-0.1; P=0.275), blood urea nitrogen (37.6+/-4.6 vs. 23.3+/-1.9; P=0.123), and 24 hr protein excretion (27.0+/-4.4 vs. 17.9+/-5.2; P=0.131) similar to single kidney ACI controls. Histologically, 45% (4/9) allografts were indistinguishable from isografts with no evidence of rejection, and were considered immunologically tolerant. Donor/recipient chimerism was not detected. All immunologically tolerant allografts had evidence of intragraft IL-10 expression. Rejecting allografts and isografts did not express intragraft IL-10. This study confirms the efficacy of pre-engraftment single-dose RAPA combined with CsA in inducing true immunologic tolerance in this stringent functional renal transplant model. The expression of intragraft IL-10 in tolerant recipients suggests a Th-2 shift as the mechanism of tolerance in this model.


Asunto(s)
Inmunosupresores/uso terapéutico , Trasplante de Riñón/inmunología , Polienos/uso terapéutico , Actinas/biosíntesis , Animales , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Ciclosporina/uso terapéutico , Cartilla de ADN , Quimioterapia Combinada , Rechazo de Injerto/inmunología , Rechazo de Injerto/patología , Tolerancia Inmunológica , Terapia de Inmunosupresión/métodos , Interleucina-10/biosíntesis , Trasplante de Riñón/patología , Trasplante de Riñón/fisiología , Masculino , Reacción en Cadena de la Polimerasa , Proteinuria , Ratas , Ratas Endogámicas ACI , Ratas Endogámicas Lew , Sirolimus , Quimera por Trasplante , Trasplante Homólogo , Trasplante Isogénico
16.
J Hepatol ; 20(1): 138-42, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8201215

RESUMEN

Methylation reactions play an important role in the transformation of endogenous and exogenous substances. Up to 85% of all transmethylation reactions occur in the liver. Several studies have shown that these metabolic processes are greatly influenced by the presence of hepatic diseases. We investigated the methylation of nicotinamide in 16 control subjects and in 29 patients with cirrhosis (19 Child A, 10 Child B). The basal serum value of N-methyl-nicotinamide was measured in all subjects. In seven controls and in nine patients with cirrhosis (5 Child A and 4 Child B), the serum levels and urinary excretion (5 and 24 h) of N-methyl-nicotinamide were also evaluated after oral administration of nicotinamide (1.5 mg/kg body weight). The basal serum levels of N-methyl-nicotinamide were significantly (p < 0.05) higher in patients with cirrhosis (Child A: median 34 ng/ml, 16th percentile 24, 84th percentile 61; Child B median 45, 16th percentile 34, 84th percentile 81) than in controls (median 22, 16th percentile 13, 85th percentile 28). After the nicotinamide load the urinary excretion and the time course of serum N-methyl-nicotinamide in cirrhosis were also higher (p < 0.05) than in controls (24 h urinary excretion = 66.2 mg +/- 5 S.D. in cirrhosis; 47.2 +/- 10.3 in controls) (area under the serum concentration versus time curve = 68 micrograms.ml-1.min-1 +/- 22 S.D. in cirrhosis; 32 +/- 15 in controls). In conclusion, our results show that cirrhosis does not impair the efficiency of nicotinamide methylation.


Asunto(s)
Cirrosis Hepática/metabolismo , Hígado/metabolismo , Metiltransferasas/metabolismo , Niacinamida/metabolismo , Femenino , Humanos , Masculino , Metilación , Persona de Mediana Edad , Niacinamida/análogos & derivados , Nicotinamida N-Metiltransferasa
17.
J Reprod Med ; 38(9): 711-5, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8254594

RESUMEN

Testyolk Buffer has been shown to enhance sperm penetration in hamster penetration assays and increase fertilization of oocytes in in vitro fertilization. Based on these findings, we compared pregnancy rates and sperm motility in intrauterine inseminations done with sperm samples washed and resuspended in Ham's F10 as compared with Testyolk buffer. Charts were reviewed retrospectively from 1,098 husband and donor intrauterine inseminations performed at the University of Florida. Data were analyzed using life table analysis and the curves compared with the Mantel-Haenszel statistical test. In addition, sperm motility in fresh sperm was observed in samples incubated in Testyolk or Ham's F10, with motility counts performed at 0, 6 and 24 hours. Four hundred ninety-two Testyolk cycles and 579 Ham's F10 cycles were compared, with cumulative pregnancy rates at one year of 53% and 44%, respectively (P = .58). With donor sperm, 229 cycles with Testyolk and 314 cycles with Ham's F10 had cumulative pregnancy rates of 68% and 48%, respectively (P = .52). With husband insemination, 264 Testyolk and 253 Ham's F10 cycles had pregnancy rates of 37% and 35%, respectively (P = .23). Fresh sperm motility in 22 samples compared at 0, 6 and 24 hours in Ham's F10 (76%, 67.8%, 56.6%) versus Testyolk (76%, 67.7%, 58.8%) revealed no significant differences. There was also no difference in total motile sperm inseminated and postwash motility in 1,098 samples with Testyolk versus Ham's F10. This study demonstrates that there is no enhanced pregnancy rate or increased sperm motility when sperm are treated with Testyolk Buffer instead of Ham's F10.


Asunto(s)
Infertilidad/terapia , Inseminación Artificial/métodos , Tablas de Vida , Motilidad Espermática , Conservación de Tejido/métodos , Adulto , Tampones (Química) , Criopreservación , Femenino , Humanos , Incubadoras , Infertilidad/etiología , Masculino , Persona de Mediana Edad , Embarazo , Estudios Retrospectivos , Soluciones , Interacciones Espermatozoide-Óvulo , Análisis de Supervivencia
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