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1.
Proc Biol Sci ; 285(1870)2018 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-29321292

RESUMEN

Life-history traits such as spawning migrations and timing of reproduction are adaptations to specific environmental constraints and seasonal cycles in many organisms' annual routines. In this study we analyse how offspring fitness constrains spawning phenology in a large migratory apex predator, the Atlantic bluefin tuna. The reproductive schedule of Atlantic bluefin tuna varies between spawning sites, suggesting plasticity to local environmental conditions. Generally, temperature is considered to be the main constraint on tuna spawning phenology. We combine evidence from long-term field data, temperature-controlled rearing experiments on eggs and larvae, and a model of egg fitness, and show that Atlantic bluefin tuna do not spawn to optimize egg and larval temperature exposure. The timing of spawning leads to temperature exposure considerably lower than optimal at all spawning grounds across the Atlantic Ocean. The early spawning is constrained by thermal inhibition of egg hatching and larval growth rates, but some other factors must prevent later spawning. Matching offspring with ocean productivity and the prey peak might be an important driver for bluefin tuna spawning phenology. This finding is important for predictions of reproductive timing in future climate warming scenarios for bluefin tuna.


Asunto(s)
Migración Animal/fisiología , Calentamiento Global , Reproducción/fisiología , Temperatura , Atún/fisiología , Animales , Océano Atlántico , Clorofila , Femenino , Larva/crecimiento & desarrollo , Óvulo/crecimiento & desarrollo , Estaciones del Año , Factores de Tiempo , Zooplancton
2.
Gen Comp Endocrinol ; 175(1): 55-64, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22015989

RESUMEN

A controlled-release implant loaded with GnRH agonist (GnRHa) was used to induce spawning in Atlantic bluefin tuna (Thunnus thynnus) during two consecutive reproductive seasons. The fish were implanted underwater and sampled between days 2 and 8 after treatment. At the time of GnRHa treatment, females were in full vitellogenesis and males in spermiation. There was a rapid burst of pituitary luteinizing hormone (LH) release at day 2 after treatment in GnRHa-treated fish, and circulating LH remained elevated up to day 8 after treatment. In contrast, control fish had significantly lower levels in the plasma, but higher LH content in the pituitary, as observed in many other cultured fishes that fail to undergo oocyte maturation, ovulation and spawning unless induced by an exogenous GnRHa. Plasma testosterone (T) and 17ß-estradiol (E(2)) were elevated in response to the GnRHa treatment in females, while 11-ketotestosterone (11-KT) but not T was elevated in males. Even though oocyte maturation and ovulation did occur in GnRHa-induced fish, no significant elevations in 17,20ß-dihydroxy-4-pregnen-3-one (17,20ß-P) or 17,20ß,21-trihydroxy-4-pregnen-3-one (20ß-S), in either the free, conjugated or 5ß-reduced,3α-hydroxylated forms was observed in fish sampled within 6 days after treatment. Interestingly, a significant peak in plasma free 17,20ß-P levels occurred in both males and females at day 8 after treatment. Histological sections of the ovaries in these females contained oocytes at the migrating germinal vesicle stage, suggesting the role of this hormone as a maturation-inducing steroid in Atlantic bluefin tuna. In conclusion, the GnRHa implants activated effectively the reproductive endocrine axis in captive Atlantic bluefin tuna broodstocks, through stimulation of sustained elevations in plasma LH, which in turn evoked the synthesis and secretion of the relevant sex steroids leading to gamete maturation and release.


Asunto(s)
Sistema Endocrino/fisiología , Hormona Liberadora de Gonadotropina/agonistas , Reproducción/fisiología , Maduración Sexual/fisiología , Atún/fisiología , Animales , Sistema Endocrino/efectos de los fármacos , Femenino , Hormona Liberadora de Gonadotropina/farmacología , Hormona Luteinizante/metabolismo , Masculino , Ovulación/efectos de los fármacos , Ovulación/fisiología , Reproducción/efectos de los fármacos , Estaciones del Año , Testosterona/metabolismo
4.
Dalton Trans ; 45(10): 4327-37, 2016 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-26674593

RESUMEN

Herein we report a synthetic study focused on the preparation of solid-solution metal-organic frameworks, MOFs, with the use of two kinds of linkers. In particular, we have explored the system composed by zinc, cobalt, 1,2,4-triazole and 4,4'-hexafluoroisopropylidenebisbenzoic acid (H2hfipbb). During this study, four new MOFs have been isolated, denoted TMPF-88 [M3(hfipbb)2(triazole)2(H2O)], TMPF-90 [M2(triazole)3(OCH2CH3)], TMPF-91 [M2(hfipbb)(triazole)2(H2O)] and TMPF-95 [M5(hfipbb)4(triazole)2(H2O)] (TMPF = transition metal polymeric framework, M = Zn, Co, or mixture of them). The study demonstrates that the addition of a second metal element during the MOF synthesis has a major effect in the formation of new phases, even at very high Zn/Co metal ratios. Furthermore, we show that during the MOF formation reaction, there is a competition among different crystal phases, where kinetically favoured phases of various compositions crystallize in short reaction times, precluding the formation of the pure solid-solution phases of other energetically more stable MOFs.

5.
Methods Find Exp Clin Pharmacol ; 11(10): 635-9, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2586196

RESUMEN

The purpose of the present report is to study the effects of antidepressants such as trimipramine, amitriptyline, maprotiline and mianserin on severe gastric mucosal lesions produced by ethanol in comparison with cimetidine (H2-antihistamine) and dexchlorepheniramine (H2-antihistamine). The percentage of macroscopic mucosal lesions caused by alcohol affects 15% of the mucosal area. But pretreated with cimetidine the affected area was 9.18%, with dexchlorepheniramine 5.01%, with trimipramine 14.46%, with amitripytline 7.94%, with maprotiline 3.8%, and with mianserin 4.07%. Microscopic evaluation reveals that ethanol produces destruction of glandular cells and injures medial and basal layers. All drugs used previously to ethanol produce a decrease of microscopical lesions. A direct relation was found between micro and macroscopical lesions in rats treated with maprotiline, mianserin and dexchlorepheniramine.


Asunto(s)
Antidepresivos/farmacología , Etanol/toxicidad , Úlcera Gástrica/inducido químicamente , Amitriptilina/farmacología , Animales , Clorfeniramina/farmacología , Cimetidina/farmacología , Femenino , Mucosa Gástrica/patología , Maprotilina/farmacología , Mianserina/farmacología , Ratas , Ratas Endogámicas , Úlcera Gástrica/patología , Úlcera Gástrica/fisiopatología , Trimipramina/farmacología
6.
J Mal Vasc ; 18(1): 13-7, 1993.
Artículo en Francés | MEDLINE | ID: mdl-8473807

RESUMEN

77 pure iliac aneurysms where detected in a group of 48 patients along a period of 21 years, and represented 12.3% of all patients having aortic, iliac, or aorto-iliac aneurysms. The study group comprised 42 men and 6 women, 48-86 years old (mean 67.8 years). The aneurysm was located on the right side in 51.9%, on left side in 48.1%. The affection of the common iliac arteries (70.1%) was more frequent than it was on the internal iliac arteries (18.2%), or in the external iliac arteries (11.7%). The diameter was from 2 to 10 cms. 44 patients out of 48 (91.6%) where symptomatic, and 15 presented a rupture syndrome (31.3%). 10 patients (20.8%) had a pulsating mass. The etiology was unknown in 8 cases (16.7%); 2 patients had a mycotic aneurysm (4.2%). The remaining 38 patients (79.1%) had an aneurysm of atheromatous origin. 5 arteritic patients (10.4%) did not have any cure for their aneurysm, because it was considered threatening for 4 of them. The fifth patient was not treated because the artery was so calcified that it could not be clamped. A lumbar sympathectomy on the same side of the lesion was realised, in addition to the peripheral surgical act for arteritis. One patient had an endoaneurysmorrhaphy, another had an exclusion by ligature section of the aneurysm. For the remaining 41 patients (83.1%) the aneurysms where flattened, and vascular continuity was re-established by a prosthesis. 7 patients (12%) decreased post-operatively.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Aneurisma de la Aorta/diagnóstico , Aneurisma Ilíaco/diagnóstico , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta/etiología , Aneurisma de la Aorta/cirugía , Femenino , Humanos , Aneurisma Ilíaco/etiología , Aneurisma Ilíaco/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Rotura Espontánea
7.
Ann Chir ; 46(2): 157-9, 1992.
Artículo en Francés | MEDLINE | ID: mdl-1605538

RESUMEN

Chondroid hamartomas disseminated in both lung fields were discovered in a 76 year old man presenting with recurrent haemoptysis. In view of this metastatic cannonball appearance and the negative investigations, exploratory thoracotomy was performed, revealing the correct diagnosis. Although classical, this form of hamartoma is rare and warrants a case report.


Asunto(s)
Hamartoma/cirugía , Neoplasias Pulmonares/cirugía , Anciano , Hamartoma/patología , Humanos , Neoplasias Pulmonares/patología , Masculino , Toracotomía
8.
Presse Med ; 17(43): 2299-301, 1988 Dec 03.
Artículo en Francés | MEDLINE | ID: mdl-2974960

RESUMEN

A technique for the surgical treatment of bronchial fistulae developed after pneumonectomy is presented. This technique, which resembles that of Abruzzini, consists of resection of the carina followed by tracheo-bronchial suture in a healthy area away from any purulent focus of infection. It is easy to perform and facilitates the treatment of thoracic empyema which is no longer maintained by the fistula.


Asunto(s)
Fístula Bronquial/cirugía , Neumonectomía/efectos adversos , Técnicas de Sutura , Tráquea/cirugía , Bronquios/cirugía , Fístula Bronquial/etiología , Empiema/terapia , Humanos , Toracoplastia , Toracostomía
9.
Actas Urol Esp ; 27(8): 640-4, 2003 Sep.
Artículo en Español | MEDLINE | ID: mdl-14587241

RESUMEN

Liposarcoma is a malignant tumor that has an embryologic origin from mesodermal tissue depending on fatty tissue. Although liposarcoma is only 0.1% of all human neoplasms, it is the most common histology subtype of retroperitoneal soft tissue sarcomas. This tumor grows slowly. Diffuse abdominal pain is its most frequent symptom and abdominal mass is the most common sign. Aggressive surgical treatment is basic to get a complete resection and a local disease control. This objective is difficult because of the large tumor size it gets in the retroperitoneal location and the multiorgan involvement that require the resection of a high percentage of contiguous organs. We report a case of a giant retroperitoneal liposarcoma presenting like continuous left hemiabdominal pain because of the visceral compression. The right kidney was involved and suffering from renal vessel enlargement without renal function. There is a high probability of microscopic residual disease and a good follow-up of the patients is necessary as well as an adjuvant radiation therapy in some cases.


Asunto(s)
Liposarcoma/patología , Neoplasias Retroperitoneales/patología , Dolor Abdominal/etiología , Calcinosis/diagnóstico , Calcinosis/patología , Femenino , Humanos , Infarto/etiología , Riñón/irrigación sanguínea , Liposarcoma/diagnóstico , Liposarcoma/cirugía , Imagen por Resonancia Magnética , Persona de Mediana Edad , Examen Físico , Neoplasias Retroperitoneales/diagnóstico , Neoplasias Retroperitoneales/cirugía , Tomografía Computarizada por Rayos X
10.
J Chir (Paris) ; 129(3): 155-9, 1992 Mar.
Artículo en Francés | MEDLINE | ID: mdl-1639887

RESUMEN

The authors report about one case of bacterial endocarditis complicated by fungal aneurysms in a superior mesenteric and a popliteal site. While the diagnosis was easy for the popliteal aneurysm, it was not so for the mesenteric aneurysm. Arteriography must have wide indications. The treatment of such aneurysms must always be medical, but surgical as well. The surgical tactics must be carefully discussed, and the restoration of vascular continuity with autologous venous material through an extra-anatomic course should be preferred.


Asunto(s)
Aneurisma Infectado/etiología , Endocarditis Bacteriana/complicaciones , Arterias Mesentéricas/fisiopatología , Arteria Poplítea/fisiopatología , Infecciones Estreptocócicas/complicaciones , Adulto , Aneurisma Infectado/diagnóstico por imagen , Aneurisma Infectado/cirugía , Angiografía , Endocarditis Bacteriana/microbiología , Endocarditis Bacteriana/cirugía , Humanos , Masculino , Arterias Mesentéricas/diagnóstico por imagen , Arterias Mesentéricas/cirugía , Arteria Poplítea/diagnóstico por imagen , Arteria Poplítea/cirugía , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/cirugía
11.
Anim Reprod Sci ; 132(1-2): 101-10, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22541277

RESUMEN

The cDNA sequences of vitellogenin receptor proteins (VgR(+) and VgR(-)), containing or lacking the O-linked sugar domain, were determined in Atlantic bluefin tuna (Thunnus thynnus L.). VgR(-) gene expression in the ovary was compared in captive-reared and wild Atlantic bluefin tuna during the reproductive cycle. Gonad samples from adult fish were sampled from 2008 to 2010 from stocks reared in captivity at different commercial fattening operations in the Mediterranean Sea and from wild individuals caught either by traditional tuna traps during their migration towards the spawning grounds in the Mediterranean Sea or by the long-line artisanal fishery. In addition, juvenile male and female Atlantic bluefin tuna were sampled from a farming facility, to obtain baseline information and pre-adulthood amounts of VgR(-). The total length of VgR(+) cDNA was 4006 nucleotides (nt) and that of VgR(-) was 3946 nt. Relative amounts of VgR(-) were greater in juvenile females and in those adults having only previtellogenic oocytes (119 ± 55 and 146 ± 26 folds more than juvenile males, respectively). Amounts of VgR(-) were less in individuals with yolked oocytes (ripening stage, May-June) and increased after spawning in July (92 ± 20 and 113 ± 13 folds more than juvenile males in ripening and post-spawning fish, respectively). These data suggest that regulation of VgR(-) is not under oestrogen control. During the ripening period, greater VgR(-) gene expression was observed in wild fish than in fish reared in captivity, possibly because of (a) differences in water temperature exposure and/or energy storage, and/or (b) an inadequate diet in reared Atlantic bluefin tuna.


Asunto(s)
Proteínas del Huevo/biosíntesis , Ovario/fisiología , Receptores de Superficie Celular/biosíntesis , Atún/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas del Huevo/genética , Femenino , Regulación de la Expresión Génica , Histocitoquímica/veterinaria , Masculino , Mar Mediterráneo , Datos de Secuencia Molecular , Oocitos/fisiología , Ovario/metabolismo , ARN/química , ARN/genética , Receptores de Superficie Celular/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Estaciones del Año , Alineación de Secuencia , Análisis de Secuencia de ADN , Atún/genética
12.
Anim Reprod Sci ; 123(1-2): 98-105, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21093994

RESUMEN

The sequence of vitellogenin A (VgA) and vitellogenin B (VgB) cDNAs in Atlantic bluefin tuna (Thunnus thynnus L.) were determined, and vitellogenin expression levels in the liver and oocyte yolk accumulation were compared in wild and captive-reared individuals. Liver and ovary samples were taken from 31 individuals reared experimentally in three commercial Atlantic bluefin tuna fattening sites in the Mediterranean Sea and from 33 wild individuals caught by commercial traps during the fish's migration towards their Mediterranean spawning grounds. The total length of VgA cDNA was 5585 nucleotides and that of VgB was 5267 nucleotides. The identity and similarity between deduced amino acid sequences of VgA and VgB were 60% and 78%, respectively. The Atlantic bluefin tuna VgA and VgB amino acid sequences have high similarities with those of other teleost fishes. Relative levels of VgA and VgB mRNAs were low in April, increased significantly during the reproductive period in May and June, and declined in July. There was a trend towards higher relative levels of VgA and VgB mRNAs in captive fish compared to wild individuals during the reproductive period. The surface occupied by eosinophilic yolk granules in fully vitellogenic oocytes, as well as the frequency of oocytes in late vitellogenesis, was significantly higher in captive compared to wild individuals. The study suggests that the experimental conditions under which Atlantic bluefin tuna individuals were reared allowed the occurrence of normal vitellogenesis, based on gene expression of VgA and VgB in the liver and yolk accumulation in the oocytes. The higher yolk accumulation and frequency of vitellogenic oocytes observed in the ovaries of captive fish suggest that improvements in feeding practices may result in an improved vitellogenic process.


Asunto(s)
Yema de Huevo/metabolismo , Hígado/metabolismo , Oocitos/metabolismo , Atún/genética , Vitelogeninas/genética , Animales , Animales Salvajes/genética , Animales Salvajes/metabolismo , Acuicultura , Clonación Molecular , Femenino , Expresión Génica , Atún/metabolismo , Vitelogeninas/biosíntesis , Vitelogeninas/metabolismo
14.
Anim Reprod Sci ; 116(3-4): 346-57, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19304415

RESUMEN

The effects of administration of gonadotropin-releasing hormone agonist (GnRHa) on proliferation and apoptosis of male germ cells were evaluated on Atlantic bluefin tuna (Thunnus thynnus L.) reared in captivity. Fish (n=19) were treated with a sustained-release delivery system loaded with GnRHa during the natural spawning season of 2004 and 2005 (June-July). Untreated Control fish (n=17) and adult wild spawners were used for comparison. Fish were sacrificed 2-8 d after GnRHa implantation and body weight and gonad weight were recorded, and gonads and blood were taken. Germ cell proliferation and apoptosis were evaluated through the immunohistochemical detection of proliferating cell nuclear antigen (PCNA) and the terminal deoxynucleotidyl transferase-mediated d'UTP nick end labelling (TUNEL) method, respectively. Plasma 11 ketotestosterone (11-KT) levels were measured using an ELISA method. Mean gonado-somatic index and seminiferous lobule diameter did not differ between GnRHa-treated and Control fish, and were significantly lower in captive-reared individuals than in wild spawners. Significant increases in 11-KT plasma levels and spermatogonial mitosis, along with a reduction of germ cell apoptosis were demonstrated in GnRHa-treated fish compared to Controls. The results suggest that GnRHa administration was effective in enhancing germ cell proliferation and reducing apoptosis in captive males through the stimulation of luteinizing hormone (LH) release and testicular 11-KT production.


Asunto(s)
Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Hormona Liberadora de Gonadotropina/agonistas , Espermatozoides/efectos de los fármacos , Atún/fisiología , Animales , Animales Salvajes , Implantes de Medicamentos , Explotaciones Pesqueras , Células Germinativas/efectos de los fármacos , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/farmacología , Masculino , Espermatozoides/fisiología , Testosterona/análogos & derivados , Testosterona/sangre , Atún/sangre
15.
Artículo en Inglés | MEDLINE | ID: mdl-7903607

RESUMEN

1. Adrenergic and cholinergic mechanisms seem to be involved in the pathogenesis of stress ulcers. 2. In this study, gastric ulcers were induced in rats by immobilization and cold. Prior intraperitoneal administration of both anticholinergic (atropine) as well as alpha-blocking medication (phenoxybenzamine) produced a very significant decrease in stress ulcers. 3. Additionally, using the technique of continuous intravenous perfusion in rats, acetylcholine was shown to have a gastric ulcerogenic effect, in contrast to noradrenaline. 4. It is concluded that acetylcholine is the peripheral mediator in stress ulcers, while noradrenaline intervenes at the encephalic level in stress ulcer pathogenesis.


Asunto(s)
Acetilcolina/metabolismo , Norepinefrina/metabolismo , Úlcera Gástrica/etiología , Estrés Fisiológico/complicaciones , Animales , Femenino , Ratas , Ratas Wistar , Úlcera Gástrica/metabolismo
16.
Chirurgie ; 115(3): 238-43; discussion 244, 1989.
Artículo en Francés | MEDLINE | ID: mdl-2805933

RESUMEN

The authors report the results of a latero-lateral colorectal anastomotic technique which includes a wide rectoplasty. Analysis is based on 46 patients with a post-operative follow-up of between 2 and 8 years. 1 patient suffered from congenital mega-colon and 45 from adenocarcinoma of the upper half of the rectum. 4 of the anastomoses followed colostomy for obstruction and 4 others were followed by a protective colostomy. Two post-operative deaths occurred and there were 3 anastomotic fistulae, one of which was asymptomatic. Hepatic metastases occurred in 10 cases and were associated with loco-regional recurrence in 5 cases. The functional results were excellent. In survivors with no evidence of local recurrence there were no cases of stenosis of the anastomosis.


Asunto(s)
Colon/cirugía , Megacolon/cirugía , Neoplasias del Recto/cirugía , Recto/cirugía , Adenocarcinoma/cirugía , Adulto , Anciano , Anastomosis Quirúrgica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
17.
J Auton Pharmacol ; 17(1): 53-7, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9201560

RESUMEN

1. 4-Aminopyridine and 3,4-diaminopyridine produced concentration-dependent contraction on guinea-pig isolated ileum incubated in Tyrode solution. The EC30 values were 1.14 x 10(-4) and 1.39 x 10(-4) M, respectively. 2. Calcium channel blockers such as verapamil, diltiazem, nifedipine, flunarizine, and lanthanum chloride antagonized the contracting effect induced by 4-aminopyridine and 3,4-diaminopyridine in guinea-pig isolated ileum. 3. Diazoxide and atropine sulphate behaved similarly as antagonists of the contracting effect induced by 4-aminopyridine and 3,4-diaminopyridine in guinea-pig isolated ileum. 4. It is concluded that the aminopyridines exert their effects through the release of acetylcholine from parasympathetic nerve terminals.


Asunto(s)
4-Aminopiridina/análogos & derivados , 4-Aminopiridina/farmacología , Íleon/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Canales de Potasio/efectos de los fármacos , 4-Aminopiridina/antagonistas & inhibidores , Acetilcolina/metabolismo , Amifampridina , Animales , Atropina/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Diazóxido/farmacología , Diltiazem/farmacología , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Femenino , Flunarizina/farmacología , Cobayas , Íleon/metabolismo , Técnicas In Vitro , Lantano/farmacología , Masculino , Contracción Muscular/efectos de los fármacos , Nifedipino/farmacología , Sistema Nervioso Parasimpático/efectos de los fármacos , Sistema Nervioso Parasimpático/metabolismo , Parasimpatolíticos/farmacología , Vasodilatadores/farmacología , Verapamilo/farmacología
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