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1.
Fish Physiol Biochem ; 49(4): 613-626, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37311916

RESUMEN

The effect of ß-glucans 1,3/1,6 from Saccharomyces cerevisiae yeast at different inclusion percentages (0.0, 0.2, 0.4, 0.6, and 0.8%) in the diet for tropical gar (Atractosteus tropicus) larvae was evaluated on growth, digestive enzyme activity and, relative expression of the immune system genes. The bioassay started on the third day after hatching (DAH) and lasted 21 days, using a total of 1500 larvae of 0.055 ± 0.008 g and, a total length of 2.46 ± 0.26 cm. Larviculture was carried out in a recirculation system with 15 tanks of 70 L using a density of 100 organisms per experimental unit. No significant differences in larval growth were observed by the inclusion of ß-glucans (p > 0.05). Digestive enzymes showed changes in lipase and trypsin activities, presenting higher values in fish fed 0.6% and 0.8% ß-glucans diets compared to the other treatments (p < 0.05). Leucine-aminopeptidase, chymotrypsin, acid phosphatase, and alkaline phosphatase activity showed higher activities in larvae fed with a 0.4% ß-glucan diet compared to the control group. The relative expression of intestinal membrane integrity (mucin 2) muc-2, (occludins) occ, (nucleotide-binding oligomerization domain) nod-2, and immune system lys (lysosome) genes showed over-expression in larvae fed the 0.4% ß-glucan diet to the rest of the treatments (p < 0.05). The inclusion of ß-glucans at 0.4-0.6% in diets for A. tropicus larvae could improve larviculture, as effects on the increase in the activity of several digestive enzymes and the expression of genes of the immune system.


Asunto(s)
Peces , beta-Glucanos , Animales , Larva , Peces/metabolismo , Intestinos , Dieta/veterinaria , Expresión Génica , beta-Glucanos/metabolismo
2.
Fish Physiol Biochem ; 46(1): 23-37, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31401709

RESUMEN

Determination of the main nutritional requirements at different developmental stages is a prerequisite in the formulation of feeds for newly cultured fish species. In the present study, the lipid and protein requirements of larvae of a native Mexican fish, the three-spot cichlid Cichlasoma trimaculatum, were assessed using a two-factor experimental design that considered four protein (35, 40, 45, and 50%) and two lipid levels (16 and 22%) on growth, survival, and digestive enzyme activities. The best growth and feed efficiency results were obtained when larvae were fed diets including 45% protein and 22% lipids. Comprehensive evaluation of the profile of digestive enzymes using multivariate analysis also demonstrated significant differences in nutritional condition generated by varying inclusion of nutrients. Thus, an increase in protein led to an increase in alkaline protease activity and a reduction in leucine aminopeptidase activity, and the reduction of dietary lipid content led to a significant increase in lipase and trypsin enzymatic activities. Based on our results, C. trimaculatum larvae have a high capacity to hydrolyze both nutrients (protein and lipids) for the high digestive enzyme activities and increase their growth, particularly with a diet containing 45% protein and 22% lipids.


Asunto(s)
Cíclidos/fisiología , Dieta , Grasas de la Dieta , Proteínas en la Dieta , Animales , Cíclidos/metabolismo , Lipasa , Lípidos , Proteínas , Tripsina
4.
Actas Urol Esp (Engl Ed) ; 42(10): 625-631, 2018 Dec.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29907261

RESUMEN

The standardisation working group of the International Continence Society has updated the Good Urodynamic Practice directives. This evidence-based ICS-GUP2016 has defined the terminology and standards of Urodynamic practice, for the laboratory and for individual practice, in quality control during cystometry and pressure-flow analysis. In addition, the working group included recommendations prior to the test and information about how to prepare the patient, as well as recommendations for the reporting of urodynamics. Based on earlier International Continence Society standardisations and current evidence, the practice of uroflowmetry, cystometry and pressure-flow study have been detailed with a view to ensuring that this Good Urodynamic Practice update contributes towards improving clinical and research quality in urodynamics.


Asunto(s)
Técnicas de Diagnóstico Urológico/normas , Urodinámica , Humanos , Traducciones
6.
Radiologia (Engl Ed) ; 60(3): 237-249, 2018.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29110903

RESUMEN

Spinal dural arteriovenous fistulas are produced by direct communication between the arterial and venous systems of the spinal cord, causing hypertension in the latter with spinal cord dysfunction. It is a rare pathology with unknown etiology and non-specific clinical symptoms that usually results in a delayed diagnosis. Often radiologists are the first to guide the disease towards an adequate diagnosis. Characteristic findings can be seen through MR or MR angiography, and may even locate the fistula in a high percentage of cases, although the pathology must be confirmed by spinal angiography. There are two treatment modalities: endovascular and surgical therapy. Endovascular treatment has improved in recent years with the advantages of a less invasive approach and is therefore usually chosen as primary therapy. In this article we review the main clinical manifestations, imaging findings and treatment of this pathology.


Asunto(s)
Malformaciones Vasculares del Sistema Nervioso Central , Médula Espinal/irrigación sanguínea , Adulto , Anciano , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Malformaciones Vasculares del Sistema Nervioso Central/cirugía , Humanos , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Vasculares
7.
Actas Urol Esp ; 41(5): 324-332, 2017 Jun.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28202287

RESUMEN

OBJECTIVE: The OAB-FIM was developed as a measure of the impact of an overactive bladder (OAB) on relatives who live with the patient. The objective of this study was conduct a cultural adaptation to Spanish (Spain) of the OAB-FIM questionnaire. METHODS: The adaptation included a conceptual and linguistic validation phase, as well as a phase for measuring the psychometric properties in 25 relatives [mean age, 63.0 years (SD, 14.3); 44% women] who regularly live with patients with OAB, who are of either sex and 18 years of age or older. We measured conceptual and linguistic equivalence, internal reliability, construct validity and content validity. We assessed the applicability and administration load. RESULTS: The OAB-FIM was conceptually and linguistically equivalent to the original, maintaining its 6 domains: social, travel, worry, irritability, sleep and sex. The interagreement correctly placed all items in their domain, except for number 10, which was placed more in worry than in irritability, motivates its reformulation. Some 2.95% of the items were missing. The floor and ceiling effects of the items varied, respectively, between 20-28%, and 0-16%. The mean time for completing the questionnaire was 5.2minutes (SD, 2.8), and 24% of the participants required some type of assistance. The α-Cronbach coefficient varied between 0.948-0.839. The correlations with similar scales in the family were moderate-high (0.407-0.753) or small-moderate with those administered to the patient (0.004-0.423). CONCLUSION: We obtained a Spanish (Spain) version of the OAB-FIM that was conceptually and linguistically equivalent to the original. The questionnaire showed good internal consistency, content and construct validity and applicability.


Asunto(s)
Salud de la Familia , Autoinforme , Vejiga Urinaria Hiperactiva , Costo de Enfermedad , Estudios Transversales , Características Culturales , Femenino , Humanos , Lenguaje , Masculino , Persona de Mediana Edad , España
8.
J Endocrinol Invest ; 39(3): 273-6, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26202044

RESUMEN

INTRODUCTION: Cushing's syndrome (CS) is a rare disease in pregnancy and its differential diagnosis is complicated. It is usually confused with complicated pregnancy cases, such us preeclampsia and gestational diabetes. This usually leads to a delayed diagnosis and is also associated with severe materno-foetal complications. PURPOSE: We present a case of a pregnant woman in her third trimester of pregnancy with CS secondary to an adrenal adenoma without response to medical treatment who underwent laparoscopic adrenalectomy without complications. DISCUSSION: Most authors consider adrenalectomy as the first-choice treatment, since it presents higher rate of successful pregnancies. However, previously published cases did not reflect this stance. These publications prefer to maintain medical treatment, allowing pregnancy to go to term and delaying adrenalectomy after childbirth. We consider that experience in laparoscopic surgery, obstetric knowledge and resources now available, all offer sufficient guarantees to carry out the laparoscopic procedure to treat CS in pregnancy even in the third trimester. Laparoscopic adrenalectomy for CS in pregnancy is a safe and efficacious procedure allowing stopping the disease and curbing the dreadful consequences it may have for both mother and foetus.


Asunto(s)
Adrenalectomía , Síndrome de Cushing/cirugía , Laparoscopía , Complicaciones del Embarazo/cirugía , Adulto , Síndrome de Cushing/patología , Femenino , Humanos , Embarazo , Complicaciones del Embarazo/patología , Tercer Trimestre del Embarazo , Pronóstico , Adulto Joven
9.
Fish Physiol Biochem ; 42(2): 517-28, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26573856

RESUMEN

Aquaculture in Mexico has been developed by the cultivation of commercial species. In Tabasco, the cultivation of native species is mainly limited by the lack of nutrition studies to support its crop profitability. Among these species is the tropical gar (Atractosteus tropicus), which has great potential for cultivation. However, the nutritional value of carbohydrates in diets for this species which contribute to improved growth and survival, have not been evalulated,. Thus, in the present investigation, isoprotein and isolipid diets have been designed based on the substitution of cellulose by corn starch (D1: 0% starch-15% cellulose, D2: 7.5% starch-7.5% cellulose and D3: 15% starch-0% cellulose) and compared with a commercial trout diet (45% protein and 16% lipids). A total of 1800 larvae (0.008 ± 0.002 g and 10.5 ± LT 0.126 mm) were used, distributed in a recirculation system in order to evaluate growth and survival for 30 days. The results show higher growth and survival of 97% of larvae fed the D3 diet, while cannibalism in the species was mitigated. Major digestive enzyme activities occurred (acid protease, alkaline protease, trypsin, chymotrypsin, leucine aminopeptidase, carboxypeptidase A, lipase, α-glucosidase and amylase) for larvae fed D3. It is concluded that the contribution of corn starch (15%) replacing cellulose in the diet improves growth and survival of this species.


Asunto(s)
Acuicultura , Dieta/métodos , Peces/fisiología , Almidón , Amilasas/metabolismo , Animales , Leucil Aminopeptidasa/metabolismo , México , Péptido Hidrolasas/metabolismo , Tripsina/metabolismo
10.
Carbohydr Polym ; 137: 726-731, 2016 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-26686185

RESUMEN

A facile method for the preparation of cobalt ferrite nanotubes by use of bacterial cellulose nanoribbons as a template is described. The proposed method relays on a simple coprecipitation operation, which is a technique extensively used for the synthesis of nanoparticles (either isolated or as aggregates) but not for the synthesis of nanotubes. The precursors employed in the synthesis are chlorides, and the procedure is carried out at low temperature (90 °C). By the method proposed a homogeneous distribution of cobalt ferrite nanotubes with an average diameter of 217 nm in the bacterial nanocellulose (BC) aerogel (3%) was obtained. The obtained nanotubes are formed by 26-102 nm cobalt ferrite clusters of cobalt ferrite nanoparticles with diameters in the 9-13 nm interval. The nanoparticles that form the nanotubes showed to have a certain crystalline disorder, which could be attributed in a greater extent to the small crystallite size, and, in a lesser extent, to microstrains existing in the crystalline lattice. The BC-templated-CoFe2O4 nanotubes exhibited magnetic behavior at room temperature. The magnetic properties showed to be influenced by a fraction of nanoparticles in superparamagnetic state.


Asunto(s)
Celulosa/química , Cobalto/química , Compuestos Férricos/química , Nanopartículas/química , Bacterias/química , Técnicas Químicas Combinatorias/métodos , Microscopía Electrónica de Rastreo , Difracción de Rayos X
11.
Fish Physiol Biochem ; 41(5): 1075-91, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25987007

RESUMEN

Changes in digestive enzyme activity and histology were studied in Atractosteus tropicus embryos, larvae and juvenile periods. Alkaline protease, chymotrypsin, carboxypeptidase A, lipase and α-amylase were detected in all periods and gradually increased until reaching the maximum peak in juveniles; meanwhile, acid protease was first detected at 5 days after hatching (dah) when first feeding started and trypsin and leucine aminopeptidase activities were detected from 19 dah, their values being increased gradually until reaching a maximum value at 31 dah. Acid and alkaline phosphatase activities increased from yolk-sac absorption (3 dah) until day 31 after hatching. Zymogram for acid protease showed two bands in active forms (0.4 and 0.5 Rfs) from day 5 after hatching and a third protease form (0.3 Rf) that appears at 31 dah. Two active forms (26.3 and 24.9 kDa) were detected using SDS-PAGE alkaline proteases zymogram at 5 dah, and an additional active form (44.1 kDa) was detected at 7 dah. Regarding the histological development of the digestive system, the exocrine pancreas containing zymogen granules was already visible at 3 dah, whereas at 5 dah first gastric glands were already detected in the stomach. Between 7 and 9 dah, the digestive tract of A. tropicus resembled that of a juvenile specimen with a well-developed and short oesophagus, stomach divided into a glandular and non-glandular (pyloric) stomach, folded intestine with pyloric caeca and a well-developed spiral valve (posterior intestine). Considering this, larvae of A. tropicus are capable of digesting several foods from yolk absorption (3 dah), maximizing its activities at 15 dah, age at which the organisms maximize its capability to absorb nutrients from diets provided.


Asunto(s)
Peces/embriología , Tracto Gastrointestinal/embriología , Tracto Gastrointestinal/metabolismo , Animales , Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/fisiología , Larva/metabolismo
12.
Fish Physiol Biochem ; 41(1): 267-79, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25547606

RESUMEN

A study was performed in order to understand the development of digestive enzymes during initial ontogeny of Cichlasoma trimaculatum, for which the activity of acidic and alkaline proteases, lipases, amylases and phosphatases was determined by means of biochemical and electrophoretic analysis. Our results showed that the activity of alkaline proteases, trypsin and chymotrypsin is present from day 6 after hatching (dah) during exogenous feeding with Artemia nauplii. The activities of carboxypeptidase A and leucine aminopeptidase are present from the first days, increasing at 6 dah and reaching their maximum activity at 9 dah while acid protease activity started at 9 dah. Furthermore, the lipase activity is detected on 6 dah and keeps increasing and decreasing on 17 dah. Amylase activity is detected on 3 dah, presenting fluctuations until 45 dah, where it reaches its maximum activity. Acid and alkaline phosphatases are detected from 3 dah and reach a maximum activity between 13 and 19 dah. The SDS-PAGE electrophoresis revealed six types of bands in the alkaline proteases, with molecular weight between 113.4 and 20.4 kDa. First three bands appear on 6 dah, but it is until 11 dah when all isoforms appear. Based on these results, it is considered that this species completes its digestive enzymatic machinery from day 9 after hatching, therefore is recommended to perform the transition from live feed to inert feed at 15 dah.


Asunto(s)
Acuicultura/métodos , Cíclidos/crecimiento & desarrollo , Sistema Digestivo/enzimología , Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/fisiología , Factores de Edad , Amilasas/metabolismo , Animales , Carboxipeptidasas A/metabolismo , Quimotripsina/metabolismo , Cíclidos/metabolismo , Sistema Digestivo/crecimiento & desarrollo , Electroforesis en Gel de Poliacrilamida , Leucil Aminopeptidasa/metabolismo , Lipasa/metabolismo , Péptido Hidrolasas/metabolismo , Tripsina/metabolismo
13.
Fish Physiol Biochem ; 40(4): 1021-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24379163

RESUMEN

Tropical gar (Atractosteus tropicus) is an economically and socially important freshwater species from Southeastern Mexico, with a high aquaculture potential. With this in mind, the purpose of this study was to characterize the digestive proteases of tropical gar juveniles through biochemical and electrophoretic analyses. Twenty specimens with an average weight of 73.6 ± 12.7 g were used to obtain stomach and intestinal tissue from which multienzymatic extracts were prepared. The general activities of the acid and alkaline proteases were evaluated, as well as the specific activities of trypsin, chymotrypsin, leucine aminopeptidase and carboxypeptidase A. The effect of the pH and temperature on the proteases was also analyzed, together with the composition of the multienzymatic extracts using protease inhibitors and electrophoretic tests. Results showed that A. tropicus have a functional stomach in which protein hydrolysis starts with pepsin and which contains endo- and exopeptidases (trypsin, chymotrypsin, leucine aminopeptidase and carboxypeptidase A) and proteases that are resistant to high temperatures (45 and 55 °C for alkaline and acid proteases, respectively) and pH values. Using zymogram technique, we found two acid protease isoforms (0.35 and 0.71 rf) and five alkaline protease isoforms (83.7, 43.7, 27.5, 24.0 and 19.4 kDa), which decrease or disappear with the different inhibitors. Thus, this species is considered to be a carnivore capable of adapting to its environment by consuming different types of proteins from preys and also could adapt rapidly to consume a compound diet with different animal protein sources.


Asunto(s)
Digestión/fisiología , Peces/metabolismo , Tracto Gastrointestinal/enzimología , Péptido Hidrolasas/metabolismo , Animales , Acuicultura/métodos , Carboxipeptidasas A/metabolismo , Quimotripsina/metabolismo , Electroforesis/veterinaria , Peces/fisiología , Concentración de Iones de Hidrógeno , Isoenzimas/metabolismo , Leucil Aminopeptidasa/metabolismo , México , Estadísticas no Paramétricas , Temperatura , Tripsina/metabolismo
14.
Actas Urol Esp ; 35(8): 448-53, 2011 Sep.
Artículo en Español | MEDLINE | ID: mdl-21550143

RESUMEN

INTRODUCTION: Pelvic organ prolapse (POP) surgery has variable results of recurrence and complications. We have aimed to analyze our outcomes in order to know the factors associated with anatomical and functional failure in POP surgery. MATERIAL AND METHODS: A retrospective study of 69 patients who underwent POP surgery at our hospital was performed. Registered variables were: Age, BMI, number of deliveries, previous pelvic surgery, menopause, quality of life, urinary incontinence, associated frequency-urgency symptoms, high POP stage, vaginal compartments repaired, type of mesh, urethro-suspension and vaginal hysterectomy during POP surgery and its complications. Patients were evaluated at 1, 6 and 12 months post-surgery. The technique was considered as failed when relapse or mesh erosion occurred and when the patient is not satisfied or there was relapse. The sample is described, analyzing the relationship of the variables studied by univariate analysis (Chi square and Mann-Whitney U test) and a study was made of which variables may have predictive value in the failure of the repair (multiple logistic regression). RESULTS: Surgery failed in 17 patients during the follow-up at one year. BMI (29.6±2.03 vs 27.1±3.32), delivery number (3.4±0.71 vs. 2.8±1.88), menopause, frequency- urgency symptoms and number of vaginal compartments repaired were associated with treatment failure although only BMI, delivery number and frequency-urgency symptoms were defined as independent predictive variables when the logistic regression was carried out. CONCLUSIONS: Overweightness-obesity, previous delivery number and frequency-urgency symptoms before surgery are factors associated to anatomical and functional failure after POP repair.


Asunto(s)
Prolapso de Órgano Pélvico/cirugía , Anciano , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Insuficiencia del Tratamiento
15.
Actas Urol Esp ; 34(5): 460-6, 2010 May.
Artículo en Español | MEDLINE | ID: mdl-20470719

RESUMEN

INTRODUCTION: Nocturnal enuresis is a disorder with a maintained historical interest. Not only the multifactorial etiopathology, also its prevalence. OBJECTIVE: We consider reviewing the literature for knowing the problematic in the calculation of the prevalence of this disease. MATERIAL AND METHOD: We searched in Pubmed database with Mesh terms: "Enuresis", "Nocturnal Enuresis", we added in the search box terms bedwetting and epidemiology or prevalence. We included manuscripts in English and Spanish with more than 1000 patients as sample, we also included review papers. We analyzed the methodology and the prevalence, when it was possible, we stratified results in age, sex and the frequency of wet nights. RESULTS: The analyzed study's methodology is heterogeneous. Therefore comparisons are difficult. Due to the difficulty within the interpretation of the overall frequency, the results are not interesting unless methodology, age range of the sample and diagnosis criteria are previously detailed. CONCLUSIONS: An own epidemiology study is necessary in order to solve our problematic.


Asunto(s)
Enuresis Nocturna/epidemiología , Humanos , Prevalencia
18.
Radiologia ; 51(4): 424-7, 2009.
Artículo en Español | MEDLINE | ID: mdl-19406440

RESUMEN

POEMS syndrome is a rare multisystemic disorder characterized by polyneuropathy (P), organomegaly (O), endocrinopathy (E), blood dyscrasia with M-protein band (M), and skin changes (S). The pathogenesis of POEMS syndrome is not completely understood. This paraneoplastic syndrome may be associated to bone lesions that are characteristically sclerotic or lytic with sclerotic halo and negative at bone scintigraphy. We report a case of a 37-year-old man with several manifestations of POEMS syndrome who presented bone lesions characteristic of osteosclerotic myeloma confirmed by bone biopsy.


Asunto(s)
Síndrome POEMS , Adulto , Humanos , Masculino , Síndrome POEMS/diagnóstico
19.
Physiol Behav ; 96(2): 333-42, 2009 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-19027764

RESUMEN

Chronic physical or psychological stress disrupts male reproductive function. Studies in our laboratory have shown that stress by immersion in cold water (ICW) and by electrical foot shocks (EFS) has inhibitory effects on male sexual behavior; these effects do not seem to be mediated by an increase in corticosterone, nor by a decrease in testosterone. On the other hand, it is known that endogenous opioids are released in the brain in response to these same stressors; consequently, they could be participating in the impairment of sexual behavior, as well as in the changes in corticosterone and testosterone caused by stress. The aim of this study was to analyze the effects of the opioid antagonist naltrexone (NTX) on male sexual behavior, corticosterone, and testosterone in both stressed sexually experienced and naive male rats. Sexually experienced adult male rats were assigned to one of the following groups (n=10 each): 1) control group, males without sexual evaluation; 2) control group, rats injected ip with saline, non-stressed; 3) control group, rats injected with NTX (3 mg/kg) non-stressed; 4) rats injected ip with saline, and stressed by EFS; 5) rats injected ip with NTX (1.5 mg/kg) and stressed by EFS; 6) rats injected ip with saline and stressed by ICW; 7) rats injected ip with NTX (1.5 mg/kg) and stressed by ICW; 8) rats injected ip with NTX (3 mg/kg) and stressed by ICW. Naive males were assigned to the same control groups but only stressed by ICW and the NTX dose used was 3 mg/kg. Injections were given 30 min before stress sessions. Stress was applied on 20 consecutive days. Male sexual behavior was assessed 15 min after EFS or 30 min after ICW, on days 1, 4, 8, 12, 15, and 20. Trunk blood was collected at the end of the experiments on day 20 of stress. Corticosterone and testosterone were evaluated by HPLC. Mount, intromission and ejaculation latencies were longer in control saline naive males compared to control saline sexually experienced males on the first day. NTX administration to control naive males caused a decrease in mount, intromission, and ejaculation latencies, as well as an increase in ejaculatory frequency/30 min, compared to control-saline only on day 1. Stressed naive males showed higher mount, intromission and ejaculation latencies, compared to control and stressed sexually experienced males, as well as comparable increase in corticosterone and decrease in testosterone plasma levels. NTX administration before exposure to stress prevented the modifications caused by stress in sexual parameters. Sexual behavior in control sexually-active males injected with saline or NTX was not modified. Saline stressed males showed the previously reported alterations in sexual behavior, as well as an increase in corticosterone and a decrease in testosterone plasma levels. Stressed males injected with NTX before exposure to stress showed no alterations in male sexual behavior. NTX in control non-stressed males did not modify corticosterone plasma levels, but did cause a significant increase in plasma testosterone. The increase in corticosterone and the decrease in testosterone due to stress, were attenuated with the opioid antagonist, both in naive and sexually experienced males. Prevention of ICW stress effects was more effective with higher doses of NTX (3 mg/kg). These data suggest that endogenous opioids could be participating in the effects caused by stress on male sexual behavior, corticosterone, and testosterone.


Asunto(s)
Corticosterona/sangre , Naltrexona/farmacología , Antagonistas de Narcóticos/farmacología , Conducta Sexual Animal/efectos de los fármacos , Estrés Psicológico/sangre , Testosterona/sangre , Análisis de Varianza , Animales , Cromatografía Líquida de Alta Presión/métodos , Frío/efectos adversos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Electrochoque/efectos adversos , Masculino , Distribución Aleatoria , Ratas , Ratas Wistar , Tiempo de Reacción/efectos de los fármacos , Estrés Psicológico/tratamiento farmacológico , Estrés Psicológico/etiología , Factores de Tiempo
20.
J Phys Chem B ; 110(14): 7296-303, 2006 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-16599501

RESUMEN

The thermal-induced changes in molecular magnets based on Prussian blue analogues, M(3)[Fe(CN)(6)](2).xH(2)O (M = Mn, Co, Ni, Cu, Zn, and Cd), were studied from infrared, X-ray diffraction, thermo-gravimetric, Mössbauer, and magnetic data. Upon being heated, these materials loose the crystalline water that enhances the interaction between the metal centers, as has been detected from Mössbauer spectroscopy data. At higher temperatures, a progressive decomposition process takes place, liberating CN(-) groups, which reduces the iron atom from Fe(III) to Fe(II) to form hexacyanoferrates(II). The exception corresponds to the cobalt compound that undergoes an inner charge transfer to form Co(III) hexacyanoferrate(II). In the case of zinc ferricyanide, the thermal decomposition is preceded by a structural transformation, from cubic to hexagonal. For M = Co, Ni, Cu, and Zn the intermediate reaction product corresponds to a solid solution of M(II) ferricyanide and ferrocyanide. For M = Mn and Cd the formation of a solid solution on heating was not detected. The crystal frameworks of the initial M(II) ferricyanide and of the formed M(II) ferrocyanide are quite different. In annealed Mn(II) ferricyanide samples, an increasing anti-ferromagnetic contribution on heating, which dominates on the initial ferrimagnetic order, was observed. Such a contribution was attributed to neighboring Mn(II) ions linked by aquo bridges. In the anhydrous annealed sample such interaction disappears. This effect was also studied in pure Mn(II) ferrocyanide. The occurrence of linkage isomerism and also the formation of Ni(III), Cu(III), and Zn(III) hexacyanoferrates(II) were discarded from the obtained experimental evidence.

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