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This paper presents a nondestructive method for accurately identifying internal flaws in metal plates, which is crucial for ensuring structural integrity in safety-critical applications. The technique relies on analyzing laser-induced ultrasound (LIU) longitudinal wave time-of-flight, as demonstrated through a theoretical five-layer model. Experimental validation was conducted using a piezo-sensor in contact with a slab containing millimetric artificial cavities immersed in air, resulting in a discrepancy of 5.05%. In contrast, experiments performed in a water medium exhibited a lower discrepancy of 2.5%. (Discrepancy refers to differences between measurements obtained through an experimental time-of-flight analysis and caliper measurements.) The results obtained in water-based experiments affirm the accuracy of the proposed model. B-scan measurements and the five-layer model were utilized to generate 2D reconstructed images, enabling precise localization and sizing of cavities and kissing bonds between plates, finding an average size of kissing bond of 30 µm. In conclusion, the proposed five-layer model, based on a longitudinal wave time-of-flight analysis, provides a straightforward framework for an easy cavity and kissing bond measurements in metal plates.
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Citrus leprosis virus C (CiLV-C) is an economically important pathogen and the main causative agent of leprosis disease in citrus orchards. The main vector of this disease, the mite Brevipalpus yothersi, is widely distributed in Mexican orchards on a wide range of citrus species. Despite the importance of both the virus and the mite, field studies recording their occurrence and co-occurrence are practically non-existent. We systematically sampled orange orchards for both CiLV-C and B. yothersi throughout the year. The distribution of the CiLV-C and B. yothersi was evaluated on each sampling occasion and their spatiotemporal associations were determined. Specifically, 100-112 orange trees, distributed in 18 rows (five or six trees per row), were sampled monthly between March 2017 and February 2018 (11 sampling dates). Twenty leaves per tree were sampled on each occasion. The number of mites per tree and the percentage of leaves per tree with disease symptoms were recorded. On each sampling occasion, spatiotemporal associations between mites and disease were determined using the Spatial Analysis by Distance Indices (SADIE) method. CiLV-C and B. yothersi were identified using molecular methods. Throughout the study, the distribution of CiLV-C was aggregated and the distribution of B. yothersi was random. No association was found between the virus and the mite on any of the sampling dates. In total, 173 mites were collected, but only 43 mites were found to be carrying CiLV-C. The reason for this lack of association between the virus and the mite, as well as the impact of our findings on the epidemiology of the disease in orange orchards, are discussed.
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Distribución Animal , Ácaros/fisiología , Virus de Plantas/fisiología , Animales , Citrus sinensis/crecimiento & desarrollo , Citrus sinensis/fisiología , Citrus sinensis/virología , México , Enfermedades de las Plantas/virología , Hojas de la Planta/fisiología , Hojas de la Planta/virología , Dinámica Poblacional , Análisis Espacio-TemporalRESUMEN
Blueberry (Vaccinium corymbosum L.) is becoming an important crop in the states of Jalisco and Michoacan in Mexico. Leaf rust, a disease causing extensive defoliation on plants with severe infections, was observed in the autumn of 2007 and it has become one of the most significant diseases of blueberry in these states. Symptoms on the upper surfaces of leaves appear as small, yellow spots that later turn necrotic as they enlarge and coalesce and eventually cover large areas of individual leaves. On the undersides of leaves, small flecks surrounded by small water-soaked halos appear, turn yellow, and produce powdery sori that are uredinia with urediniospores. Uredinia were hypophyllous, scattered to gregarious and at times superficially appearing confluent, up to about 300 µm in diameter, dome shaped and peridium hemispherical in cross section, orangish, becoming pulverulent, lacking obviously enlarged, well-differentiated ostiolar cells. Urediniospores were subglobose, obovate, oblong or ellipsoid, 17.6 to 27.2 × 12.8 to 17.6 µm, with hyaline, echinulate walls that are 1.2 to 1.8 µm thick, and with yellow-to-hyaline contents. Telia were not observed. On the basis of uredinial morphology (3,4), the rust was identified as Thekopsora minima P. Syd. & Syd. To distinguish this rust from other rust species causing disease on Vaccinium (2,3), a 1,414-bp region consisting of ITS2 and the 5' end of the 28S was amplified with primers Rust2inv/LR6 from uredinial lesions on infected leaves of V. corymbosum 'Biloxi' and sequenced (BPI 880580; GenBank Accession No. HM439777) (1). Results of a BLAST search of GenBank found 100% (1,414 of 1,414) identity to T. minima (GenBank Accession No. GU355675) from South Africa (3). Pathogenicity tests were completed as follows: (i) during the autumn of 2009, rusted leaves of cvs. Biloxi and Sharpblue were collected from the field; (ii) mature leaves from healthy plants of both blueberry cultivars were surface disinfested with 1% sodium hypochlorite for 2 min and rinsed with sterile distilled water; (iii) fresh urediniospores from rusted leaves were brushed directly onto the undersides of disinfested detached leaves; (iv) to avoid drying, wet cotton balls were placed on the petioles of inoculated leaves that were subsequently placed in resealable plastic bags; and (v) leaves were then incubated in a growth chamber at 22°C with a 12-h photoperiod. For each cultivar, 20 leaves were inoculated and five uninoculated leaves were included as controls and the test was repeated once. Yellow uredinia were observed 13 and 10 days after inoculation in cvs. Biloxi and Sharpblue, respectively. Leaf symptoms and uredinial characters were the same as observed previously in the field. To our knowledge, this is the first report of T. minima in Mexico. This report is significant for growers who need a diagnosis to control the disease and for breeders and plant pathologists who should consider developing more resistant cultivars. References: (1) M. C. Aime. Mycoscience 47:112, 2006. (2) F. L. Caruso and D. C. Ramsdell, eds. Compendium of Blueberry and Cranberry Diseases. The American Phytopathological Society, St. Paul, MN, 1995. (3) L. Mostert et al. Plant Dis. 94:478, 2010. (4) P. Sydow and H. Sydow. Monographia Uredinearum. Vol. III. Fratres Borntraeger, Leipzig, Germany, 1915.
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INTRODUCTION: Anticonvulsant drugs have been used in the treatment of alcohol detoxification. The purpose of the present study was to evaluate the efficacy and safety of zonisamide in a sample of patients presenting alcohol withdrawal syndrome. METHOD: In this 3-week, randomized, flexible-dose trial, 40 inpatients with alcohol dependence disorder received zonisamide or diazepam for detoxification. Zonisamide was started at a dose of 400-600 mg/day (week 1), tapering to a minimum dose of 100-300 mg/day (week 3). Diazepam was administered using a similar regimen (from 130-50 mg/day tapering to 5-15 mg/day). Subjects were treated initially (weeks 1 and 2) in an inpatient unit and for the final week in an outpatient facility. During the inpatient period, the Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar) was used to assess the efficacy of each substance. During the outpatient period the Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar), Hamilton Anxiety Rating Scale, Hamilton Depression Rating Scale, and a craving scale were used. RESULTS: All subjects completed the study. During the inpatient period both drugs reduced alcohol withdrawal symptoms, but the decrease was more marked in the zonisamide group. At the end of the study (week 3) participants treated with zonisamide showed lower CIWA-Ar scores than subjects receiving diazepam. Also, individuals in the zonisamide group had less craving for alcohol, less anxiety, and less daytime sedation compared with participants treated with diazepam. CONCLUSION: Zonisamide can be a valuable alternative to benzodiazepines in the prevention of alcohol withdrawal syndrome.
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Anticonvulsivantes/uso terapéutico , Diazepam/uso terapéutico , Etanol/efectos adversos , Isoxazoles/uso terapéutico , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Adulto , Alcoholismo/tratamiento farmacológico , Alcoholismo/terapia , Anticonvulsivantes/efectos adversos , Diazepam/efectos adversos , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Isoxazoles/efectos adversos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Síndrome de Abstinencia a Sustancias/complicaciones , Resultado del Tratamiento , Adulto Joven , ZonisamidaRESUMEN
OBJECTIVE: Plantar fasciitis is a common cause of heel pain. The aetiology of this condition remains unclear. Patients typically have pain upon palpation of the medial plantar calcaneal region. Extracorporeal shockwave therapy has shown favourable outcomes in various studies. The aim of this study was to compare the effect of focused extracorporeal shockwave therapy with radial pressure wave therapy. PATIENTS AND METHODS: Seventy-nine non-randomised patients diagnosed with plantar fasciitis were included between January 2017 and June 2018. Patients from the Arnau de Vilanova Hospital in Valencia were treated with focused extracorporeal shockwave therapy, and patients from Llíria Hospital with radial pressure wave therapy. Measured outcome variables were: visual analog scale; ultrasonographic measurement of plantar fascia thickness; self-reported foot-specific pain and disability using the Foot Function Index; self-reported health-related quality of life using the Euroqol-5D; self-reported pain and limitations of activity using the Roles & Maudsley Scale. RESULTS: At inclusion, the 2groups showed no significant differences in demographic or clinical characteristics. Three months after treatment completion, both groups showed improvement in all outcome variables, without statistically significant differences between the 2groups. No adverse effects or complications were observed. CONCLUSIONS: Both extracorporeal shockwave therapy and radial pressure wave therapy are effective treatments for plantar fasciitis.
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Tratamiento con Ondas de Choque Extracorpóreas/métodos , Fascitis Plantar/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor/métodos , Calidad de VidaRESUMEN
BACKGROUND: Different neuropsychological studies have shown schizophrenic patients to have executive function deficits, as illustrated by their performance in neuropsychological tasks such as the Wisconsin Card Sorting Test (WCST); certain studies have described a relationship between these deficits and negative symptoms. Schizophrenic patients also exhibit a high lifetime prevalence (40-50%) of comorbid substance use disorders (SUDs). However, little attention has been paid to this comorbidity (dual diagnosis) in studies associating executive functions and negative symptoms. SAMPLING AND METHODS: Our objective is to investigate the relationship between performance in the WCST and psychopathology as measured by the Positive and Negative Syndrome Scale (PANSS) in a sample of 65 male schizophrenic patients with a history of SUDs (Sch SUD+) and in a sample of 48 male schizophrenic patients without such history (Sch SUD-). RESULTS: In the Sch SUD- group, patients who completed 4 or more categories in the WCST ('good performers') obtained a mean score of 21.2 +/- 8.8 on the negative subscale of the PANSS, compared with a mean score of 27.8 +/- 8.6 in those who completed 3 or less ('poor performers'); these differences were statistically significant (p = 0.015). In the Sch SUD+ group, however, no association was found between WCST performance and the PANSS negative subscale score. CONCLUSIONS: The presence of a history of comorbid SUDs should be taken into consideration in studies investigating executive functions and negative symptoms in schizophrenia.
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Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/epidemiología , Pruebas Neuropsicológicas , Esquizofrenia/epidemiología , Psicología del Esquizofrénico , Trastornos Relacionados con Sustancias/epidemiología , Adulto , Diagnóstico Dual (Psiquiatría) , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Humanos , Masculino , Esquizofrenia/diagnóstico , Índice de Severidad de la Enfermedad , Trastornos Relacionados con Sustancias/diagnósticoRESUMEN
p53 wild-type is a tumor suppressor gene involved in DNA gene transcription or DNA repair mechanisms. When damage to DNA is unrepairable, p53 induces programmed cell death (apoptosis). The mutant p53 gene is the most frequent molecular alteration in human cancer, including breast cancer. Here, we analyzed the genetic alterations in p53 oncogene expression in 55 patients with breast cancer at different stages and in 8 normal women. We measured by ELISA assay the serum levels of p53 mutant protein and p53 antibodies. Immunohistochemistry and RT-PCR using specific p53 primers as well as mutation detection by DNA sequencing were also evaluated in breast tumor tissue. Serological p53 antibody analysis detected 0/8 (0%), 0/4 (0%) and 9/55 (16.36%) positive cases in normal women, in patients with benign breast disease and in breast carcinoma, respectively. We found positive p53 mutant in the sera of 0/8 (0.0%) normal women, 0/4 (0%) with benign breast disease and 29/55 (52.72%) with breast carcinoma. Immunohistochemistry evaluation was positive in 29/55 (52.73%) with mammary carcinoma and 0/4 (0%) with benign breast disease. A very good correlation between p53 mutant protein detected in serum and p53 accumulation by immunohistochemistry (83.3% positive in both assays) was found in this study. These data suggest that detection of mutated p53 could be a useful serological marker for diagnostic purposes.
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Biomarcadores de Tumor/genética , Neoplasias de la Mama/patología , Mutación , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , Anciano de 80 o más Años , Autoanticuerpos/sangre , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/inmunología , Neoplasias de la Mama/sangre , Neoplasias de la Mama/genética , Carcinoma in Situ/sangre , Carcinoma in Situ/genética , Carcinoma in Situ/patología , Carcinoma Ductal de Mama/sangre , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunohistoquímica/métodos , Persona de Mediana Edad , Estadificación de Neoplasias , Proteína p53 Supresora de Tumor/sangre , Proteína p53 Supresora de Tumor/inmunologíaRESUMEN
The TaqIA polymorphism linked to the DRD2 gene has been associated with alcoholism. The aim of this work is to study attention and inhibitory control as per the continuous performance test and the stop task in a sample of 50 Spanish male alcoholic patients split into two groups according to the presence of the TaqIA1 allele in their genotype. Our results show that alcoholics carrying the TaqIA1 allele present lower sustained attention and less inhibitory control than those patients without such allele.
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Alcoholismo/genética , Atención , Polimorfismo Genético/genética , Receptores de Dopamina D2/genética , Receptores Acoplados a Proteínas G/genética , Adulto , Alelos , Genotipo , Humanos , Masculino , EspañaRESUMEN
Pathological gambling (PG) has been associated to both impulsiveness and attention deficit/hyperactivity disorder (ADHD) in different studies. Our objective was to compare different impulsivity and sustained attention variables, using both behavioural tasks and self-administered questionnaires, in a group of pathological gamblers with a history of childhood ADHD (PG-ADHD; n = 16), a group of pathological gamblers without this history (PG-non-ADHD; n = 39), and a control group (n = 40). As instruments of measure, we used the stop signal task (to evaluate inhibitory control/impulsivity), the differential reinforcement of Low Rate Responding Task (delay of gratification/impulsivity) and the Continuous Performance Test (sustained attention). The Barratt Impulsivity Scale (BIS-11) was used as a self-administered questionnaire to measure impulsiveness. Our results show that patients in the PG-ADHD group exhibit a significantly lower capacity to delay gratification than those in the PG-non-ADHD and control groups, and less inhibitory control than patients in the PG-non-ADHD group. On self-administered questionnaires such as the BIS-11 the PG-ADHD group obtained higher scores than the PG-non-ADHD and control groups. However, no differences were found with respect to sustained attention using the CPT. Our results suggest a possible selective implication of the prefrontal cortex in PG, which would be especially evident in those with a childhood history of ADHD.
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Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Juego de Azar/psicología , Conducta Impulsiva/fisiopatología , Control Interno-Externo , Autoevaluación (Psicología) , Adulto , Análisis de Varianza , Niño , Femenino , Humanos , Persona de Mediana Edad , Determinación de la Personalidad/estadística & datos numéricos , Escalas de Valoración Psiquiátrica , PsicometríaRESUMEN
INTRODUCTION: Several different follow-up studies have shown that attention deficit hyperactivity disorder (ADHD) can persist into adulthood. AIM: To review the findings in adults with ADHD related to alterations in the executive functions. DEVELOPMENT: Research conducted among children with ADHD has revealed the existence of alterations in different tasks that evaluate the executive functions, such as the planning test, sustained attention tasks, cognitive flexibility, verbal fluency and working memory tasks, as well as several inhibition response tasks. In adults with ADHD, despite the lower number of reports in the literature and the methodological shortcomings that exist in some studies, analogous results have also been described with respect to executive functioning, namely, disorders affecting inhibition response, the capacity for planning, difficulties in cognitive flexibility and verbal fluency, and problems with working memory, which include aspects of spatial working memory, logical or visual memory. CONCLUSIONS: The findings we have available at present enable us to confirm the persistence of executive dysfunctions in adult patients with ADHD that are similar to those observed in children with ADHD.
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Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Actividad Nerviosa Superior/fisiología , Adulto , Trastorno por Déficit de Atención con Hiperactividad/psicología , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/fisiopatología , Toma de Decisiones , Trastornos Disruptivos, del Control de Impulso y de la Conducta/etiología , Trastornos Disruptivos, del Control de Impulso y de la Conducta/fisiopatología , Humanos , Inhibición Psicológica , Trastornos de la Memoria/etiología , Trastornos de la Memoria/fisiopatología , Pruebas Neuropsicológicas , Trastornos del Habla/etiología , Trastornos del Habla/fisiopatologíaRESUMEN
OBJECTIVES: The primary purpose of this study was to determine the acute and long-term hemodynamic and clinical effects of irbesartan in patients with heart failure. BACKGROUND: Inhibition of angiotensin II production by angiotensin-converting enzyme (ACE) inhibitors reduces morbidity and mortality in patients with heart failure. Irbesartan is an orally active antagonist of the angiotensin II AT1 receptor subtype with potential efficacy in heart failure. METHODS: Two hundred eighteen patients with symptomatic heart failure (New York Heart Association [NYHA] class II-IV) and left ventricular ejection fraction < or = 40% participated in the study. Serial hemodynamic measurements were made over 24 h following randomization to irbesartan 12.5 mg, 37.5 mg, 75 mg, 150 mg or placebo. After the first dose of study medication, patients receiving placebo were reallocated to one of the four irbesartan doses, treatment was continued for 12 weeks and hemodynamic measurements were repeated. RESULTS: Irbesartan induced significant dose-related decreases in pulmonary capillary wedge pressure (average change -5.9+/-0.9 mm Hg and -5.3+/-0.9 mm Hg for irbesartan 75 mg and 150 mg, respectively) after 12 weeks of therapy without causing reflex tachycardia and without increasing plasma norepinephrine. The neurohormonal effects of irbesartan were highly variable and none of the changes was statistically significant. There was a significant dose-related decrease in the percentage of patients discontinuing study medication because of worsening heart failure. Irbesartan was well tolerated without evidence of dose-related cough or azotemia. CONCLUSIONS: Irbesartan, at once-daily doses of 75 mg and 150 mg, induced sustained hemodynamic improvement and prevented worsening heart failure.
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Antagonistas de Receptores de Angiotensina , Antihipertensivos/uso terapéutico , Compuestos de Bifenilo/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Hemodinámica/efectos de los fármacos , Tetrazoles/uso terapéutico , Adolescente , Adulto , Antihipertensivos/administración & dosificación , Compuestos de Bifenilo/administración & dosificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/fisiopatología , Humanos , Irbesartán , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Receptor de Angiotensina Tipo 1 , Receptor de Angiotensina Tipo 2 , Seguridad , Método Simple Ciego , Tetrazoles/administración & dosificación , Resultado del TratamientoRESUMEN
INTRODUCTION: Alcohol withdrawal syndrome may be accompanied by severe complications, such as epileptic syndromes or delirium tremens. A number of pharmacological strategies, especially benzodiazepines (BZD), have been used in their treatment and prevention, although problems can arise from the use of these drugs due to their addictive properties. The classical anticonvulsive drugs are rarely employed as an alternative because of their side effects, but the latest generation of substances could be especially useful. AIMS. The aim of this study was to examine the safety of oxcarbazepine (OXC) in the prevention of epileptic seizures and complications deriving from the withdrawal syndrome in alcohol detoxification treatment. PATIENTS AND METHODS: The study involved a comparison of two groups of patients with a syndrome of physical dependence on alcohol, 42 of whom were treated with OXC and the remaining 42 received BZD as part of a programmed detoxification therapy. RESULTS: Both OXC and BZD were equally efficient in preventing the appearance of epileptic complications and in reducing withdrawal symptoms. Overall, OXC produced fewer adverse events (p < 0.001) and offered fewer problems when it came to ending administration (p < 0.001). CONCLUSIONS: OXC can be a valuable alternative to BZD and other pharmacological treatments in the prevention of complications in detoxification therapy, especially because of the absence of addictive properties and its having a better safety profile than classical anticonvulsant drugs.
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Delirio por Abstinencia Alcohólica/tratamiento farmacológico , Anticonvulsivantes/uso terapéutico , Carbamazepina/análogos & derivados , Adulto , Alcoholismo/diagnóstico , Alcoholismo/terapia , Anticonvulsivantes/efectos adversos , Carbamazepina/efectos adversos , Carbamazepina/uso terapéutico , Epilepsia/tratamiento farmacológico , Humanos , Persona de Mediana Edad , OxcarbazepinaRESUMEN
Rice is attacked by Steneotarsonemus spinki Smiley, a mite that has dispersed throughout many countries causing important loss on rice production. Rice plants of the variety Morelos A-92 were infested with S. spinki, and its population growth was estimated along plant development. Further, the morphological and histological injuries associated to the mite attack were characterized. The highest infestation level was obtained 13 weeks after plant infestation, with an average of 58.5 mites per plant, predominantly females. Morphological injuries were categorized from level 0 (no injuries from uninfested plants) to level 3, characterized by the highest injuries represented by blotches on the adaxial epidermis of the leaf sheath and on panicles and grains. Plants ranked within levels 0, 1, and 2 for morphological injury did not exhibit clear histological injuries, while those at level 3 exhibited histological injury characterized by destruction of cells of the adaxial epidermis, disorder, color change, and hypertrophy in the mesophyll cells, as well as color change in the abaxial epidermis. Thus, it presented a significant correlation between morphological injuries and mite density level, which can be further adopted to help the control decision-making process for this mite on rice.
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Ácaros/fisiología , Oryza/parasitología , Animales , Femenino , Masculino , México , Crecimiento DemográficoRESUMEN
Omapatrilat, a novel vasopeptidase inhibitor, is a highly potent and selective inhibitor of neutral endopeptidase and angiotensin-converting enzyme; its therapeutic potential is being investigated for treatment of hypertension and heart failure. In the present study, the safety, tolerability, and hemodynamic effects of single oral doses of omapatrilat (1 to 50 mg) are compared with placebo in patients with heart failure. Patients with heart failure (New York Heart Association functional class II to IV) and a resting left ventricular ejection fraction < or = 40% were enrolled in a double-blind, placebo-controlled, sequential-panel study of single doses of omapatrilat of 1, 2.5, 5, 10, 25, or 50 mg, followed by hemodynamic assessment for 24 hours. At 4 to 6 hours after dosing, the 25- and 50-mg doses of omapatrilat, compared with placebo, reduced mean pulmonary capillary wedge pressure by approximately 6 mm Hg from 20 and 23 mm Hg at baseline to 14 and 16 mm Hg. The 50-mg omapatrilat dose maintained this effect compared with placebo with an approximately 2.5-mm Hg reduction in mean pulmonary capillary wedge pressure at 24 hours. Omapatrilat improved additional hemodynamic parameters, including cardiac index, systemic vascular resistance, stroke volume index, and mean arterial pressure. Additionally, by 2 hours after dosing with omapatrilat 25 and 50 mg, a trend in peak increases from baseline in plasma atrial natriuretic peptide (twofold) and cyclic guanosine monophosphate (nearly twofold) was observed. Moreover, omapatrilat was well tolerated. Thus, omapatrilat administered orally to patients with heart failure was safe and well tolerated and resulted in improved hemodynamic performance.
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Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Hemodinámica , Piridinas/uso terapéutico , Tiazepinas/uso terapéutico , Administración Oral , Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , New York , Estudios Prospectivos , Piridinas/administración & dosificación , Tiazepinas/administración & dosificaciónRESUMEN
In vitro and in vivo release of pituitary hormones were studied in the presence of (hydroxyproline9)LHRH ((Hyp)LHRH), a newly characterized endogenous molecular form of LHRH. Results were compared to those obtained with LHRH itself. (Hyp)LHRH, as LHRH, stimulated both luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release in a homothetic manner. The hydroxylated compound was, however, 24 times (in vitro) and 5 times (in vivo) less potent than LHRH. The lower activity of (Hyp)LHRH than of LHRH in the in vitro assay correlated well with a 28-fold lesser potency in a binding test using pituitary membrane preparations. The higher relative potency and the prolonged effect of (Hyp)LHRH in the in vivo test were related to a lesser susceptibility of the hydroxylated form to proteolytic degradation. Effects of LHRH and of (Hyp)LHRH were not additive, both peptides were equally able to desensitize gonadotrophs to a subsequent challenge by the other. Taken together, these observations suggest that both forms of LHRH act at the same receptor site. The lesser affinity of the hydroxylated compound is compensated to a certain extent by its higher resistance to enzymatic degradation. It is concluded that in spite of its lesser potency, (Hyp)LHRH may participate in the regulation of gonadotropins.
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Hormona Folículo Estimulante/metabolismo , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Luteinizante/metabolismo , Adenohipófisis/efectos de los fármacos , Animales , Castración , Células Cultivadas , Ditiotreitol/farmacología , Femenino , Hormona Folículo Estimulante/sangre , Hormona Liberadora de Gonadotropina/farmacología , Hormona Luteinizante/sangre , Masculino , Adenohipófisis/metabolismo , Radioinmunoensayo , Ratas , Ratas EndogámicasRESUMEN
The effect of thyroid hormones (TH) on the metabolism of thyrotropin-releasing hormone (TRH) in the olfactory bulb (OB) was compared with the hypothalamic response to TRH. Two methods were used to induce hypothyroidism: propylthiouracyl-methimazole (PTU-M) or 131I treatment. Hyperthyroidism was produced by 3,3',5-triiodo-L-thyronine (T3) injections to the hypothyroid animals. With PTU-M treatment, paraventricular TRH mRNA levels increased 57% and returned to the euthyroid level with T3 treatment. In OB, TRH mRNA was not altered. The TRH content was unaffected in the mediobasal hypothalamus of PTU-M-treated animals whereas it was reduced in OB (31%) with no further response upon T3 treatment. 131I-induced hypothyroidism did not modify the OB TRH content but it was decreased (31%) in hyperthyroids. In the median eminence, TRH increased 26% in hypothyroids, and the response was reversed with T3. Our results demonstrate that treatments that change thyroid status can alter TRH levels in the OB, probably at a translational or postranslational level, though the effects may be pharmacological.
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Sistema Hipotálamo-Hipofisario/metabolismo , Hipotiroidismo/metabolismo , Bulbo Olfatorio/metabolismo , Núcleo Hipotalámico Paraventricular/metabolismo , Adenohipófisis/metabolismo , Hormona Liberadora de Tirotropina/metabolismo , Animales , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Masculino , Metimazol/farmacología , Bulbo Olfatorio/efectos de los fármacos , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Adenohipófisis/efectos de los fármacos , Propiltiouracilo/farmacología , Biosíntesis de Proteínas , Procesamiento Proteico-Postraduccional , Ratas , Ratas Wistar , Hormonas Tiroideas/farmacologíaRESUMEN
BACKGROUND: Mesothelial integrity is essential for the prevention of pericardial adhesions. This study was performed to determine the effect of physical protection of the pericardium on mesothelial integrity. METHODS: A pericardial biopsy specimen was obtained at the time of pericardiotomy (0 minutes) in 10 patients undergoing a cardiac operation for the first time. The left free edge of the pericardiotomy was plicated inward to protect the mesothelium. Biopsy specimens were obtained from the protected and unprotected pericardium at 45 and 90 minutes after the start of extracorporeal circulation. Mesothelial integrity and the local inflammatory response were then assessed and graded histologically. RESULTS: The mesothelium was found to be present in the protected specimens at 0, 45, and 90 minutes, but it was found to be denuded in the unprotected specimens (p = 0.003 at 45 minutes; p = 0.004 at 90 minutes). Local inflammation was totally established in both the protected and unprotected specimens at 45 minutes. CONCLUSIONS: Physical agents appear to be the main factor that is damaging to the pericardial mesothelium, and this is an important concept to be taken into consideration when designing a method to prevent pericardial adhesions.
Asunto(s)
Pericardio/patología , Adulto , Anciano , Biopsia , Epitelio/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pericarditis/patología , Pericardio/cirugía , Factores de Tiempo , Adherencias Tisulares/patologíaRESUMEN
Thyrotropin releasing hormone (TRH; pglu-his-proNH2) is inactivated, in the extracellular space, by pyroglutamyl aminopeptidase II (PPII), a narrow specificity ectopeptidase. In adenohypophysis, multiple hormones regulate PPII surface activity. The intracellular pathways of regulation are still poorly understood. Since some of the neurohormones which regulate PPII activity, including TRH and dopamine, transduce in part their effect through modulation of arachidonic acid (AA) mobilization, we have tested its role in regulation of PPII activity in primary cultures of rat adenohypophyseal cells. Melittin concentrations from 0.25 to 1 ug/ml induced a rapid decrease of PPII activity; 0.5 ug/ml caused a maximum effect (38-45% inhibition) at 20-30 min. AA (0.5 or 5 uM) also inhibited PPII activity (42-72%, maximum at 20 min); AA effect was reversible, with values approaching control at 1 h. The inhibitory effect of AA was blocked by lipoxygenase (10 uM nordihidroguaiaretic acid) but not ciclooxygenase inhibitors (10 uM indomethacin) suggesting the involvement of the lipoxygenase pathway. These data show that production of arachidonic acid by adenohypophyseal cells can rapidly but transiently down regulate surface PPII activity. This is the first evidence that AA mobilization can regulate the activity of an ectopeptidase.
Asunto(s)
Aminopeptidasas/antagonistas & inhibidores , Ácido Araquidónico/fisiología , Adenohipófisis/enzimología , Aminopeptidasas/metabolismo , Animales , Ácido Araquidónico/metabolismo , Ácido Araquidónico/farmacología , Regulación hacia Abajo/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Femenino , Meliteno/farmacología , Fosfolipasas A/metabolismo , Adenohipófisis/efectos de los fármacos , Adenohipófisis/fisiología , Ácido Pirrolidona Carboxílico/análogos & derivados , Ratas , Ratas Wistar , Receptores de Hormona Liberadora de Tirotropina/fisiología , Sistemas de Mensajero Secundario/efectos de los fármacos , Sistemas de Mensajero Secundario/fisiología , Hormona Liberadora de Tirotropina/fisiologíaRESUMEN
The TaqIA1 allele of the dopamine receptor gene D2 (DRD2) has been associated with alcoholism, as well as with other addictive behaviours. The exact nature of how the presence of this allele can be a vulnerability factor in the development of alcoholism remains unclear. In this study we found that the presence in the DRD2 genotype of the TaqIA1 allele in Spanish alcoholics is associated with higher levels of urine homovanillic acid (HVA) when compared to patients homozygous for the TaqIA2 allele. A sample of 142 Spanish male alcoholic patients was split into 2 groups on the basis of the presence or absence of the A1 allele in their genotype. The urine sample was analyzed by high performance liquid cromatography (HPLC), and the concentration of homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA) and vanilylmandelic acid (VMA) was determined. We found a statistical difference in the concentration of HVA between the groups, that suggests this polymorphism could be related to the variance of urine HVA levels.
Asunto(s)
Alcoholismo/genética , Alcoholismo/orina , Ácido Homovanílico/orina , Polimorfismo Genético/genética , Receptores de Dopamina D2/genética , Adolescente , Adulto , Anciano , Alcoholismo/epidemiología , Alelos , Monoaminas Biogénicas/orina , Cromatografía Líquida de Alta Presión , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , España/epidemiologíaRESUMEN
OBJECTIVE: To evaluate the nutritional status of vitamin D in urban populations of healthy elderly people living at home, in different regions of Argentina. DESIGN: Cross-sectional study. SUBJECTS: In total, 386 ambulatory subjects over 65 y of age from seven cities (between latitude 26 degrees S and 55 degrees S) were asked to participate between the end of winter and the beginning of spring. Of these, 369 accepted, 30 were excluded because of medical history or abnormal biochemical determinations. Finally, 339 subjects (226 women and 113 men) (X+/-s.d.) (71.3+/- 5.2 y) were included. RESULTS: Serum 25OHD levels were lowest in the South (latitude range: 41 degrees S-55 degrees S): 14.2+/-5.6 ng/ml (P<0.0001vs North and Mid regions); highest in the North (26 degrees S-27 degrees S): 20.7+/-7.4 ng/ml (P<0.03 vs Mid, P<0.0001vs South); and intermediate in the Mid region (33 degrees S-34 degrees S) 17.9+/-8.2 ng/ml. Serum mid-molecule PTH (mmPTH) and 25OHD were inversely related: (r=-0.24, P<0.001). A cutoff level of 25OHD at which serum mmPTH levels began to increase was established at 27 ng/ml. A high prevalence (87-52%) of subjects with 25OHD levels in the deficiency-insufficiency range (25OHD levels <20 ng/ml) was detected. CONCLUSION: This study shows that vitamin D deficiency/insufficiency in the elderly is a worldwide problem. Correction of this deficit would have a positive impact on bone health of elderly people.