Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Más filtros

Bases de datos
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Platelets ; 33(4): 621-631, 2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35042433

RESUMEN

Platelets express P2X1 receptors and our data also show the expression of P2X7 receptors. We studied the role of both receptors in platelet apoptosis by incubation of PRP with P2X agonists, then centrifuged to remove viable platelets, and analyzed the supernatant by flow cytometry to identify a sparse platelet-derived population that stained with MitoTracker dyes and CD41. BzATP, a potent agonist of P2X receptors, and ABT737, an activator of intrinsic apoptosis, produced altered platelets that stained moderately for annexin V and corresponded to an early stage apoptotic platelet (ESAP). Over a range of BzATP concentrations, we observed a dose-dependent formation of ESAPs between 5 and 500 uM BzATP, together with a variable formation of ESAPs at nanomolar ATP or BzATP (50-200 nM). Production of ESAPs occurred with αß-meATP, while responses with either BzATP or αß-meATP showed desensitization at a higher agonist concentration. Formation of ESAPs by either 100 nM or 0.5 mM BzATP was inhibited by preincubation of platelets with latrunculin A, an inhibitor of the actin cytoskeleton that prevents apoptosis. ESAP production was totally inhibited by preincubation of platelets with methyl-beta-cyclodextrin, which removes cholesterol from lipid rafts. Our data show that both P2X1 and P2X7 receptors are localized in platelet lipid rafts where P2X-agonists act to produce early stage apoptotic platelets.


Asunto(s)
Plaquetas , Receptores Purinérgicos P2X7 , Adenosina Trifosfato/metabolismo , Apoptosis , Plaquetas/metabolismo , Calcio/metabolismo , Citometría de Flujo , Humanos , Receptores Purinérgicos P2X7/metabolismo
2.
Lung ; 198(1): 43-52, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31915922

RESUMEN

INTRODUCTION: The mechanism of fast inspiratory flow rate (VI') induced lung injury is unclear. As fast VI' increases hysteresis, a measure of surface tension at the air-liquid interface, surfactant release or function may be important. This experimental study examines the contribution of impaired surfactant release or function to dynamic-VILI. METHODS: Isolated perfused lungs from male Sprague Dawley rats were randomly allocated to four groups: a long or short inspiratory time (Ti = 0.5 s; slow VI' or Ti = 0.1 s; fast VI') at PEEP of 2 or 10 cmH2O. Tidal volume was constant (7 ml/kg), with f = 60 breath/min. Forced impedance mechanics (tissue elastance (Htis), tissue resistance (Gtis) and airway resistance (Raw) were measured at 30, 60 and 90 min following which the lung was lavaged for surfactant phospholipids (PL) and disaturated PL (DSP). RESULTS: Fast VI' resulted in a stiffer lung. Concurrently, PL and DSP were decreased in both tubular myelin rich and poor fractions. Phospholipid decreases were similar with PEEP. In a subsequent cohort, laser confocal microscopy-based assessment demonstrated increased cellular injury with increased VI' at both 30 and 90 min ventilation. CONCLUSION: Rapid VI' may contribute to ventilator induced lung injury (VILI) through reduced surfactant release and/or more rapid reuptake despite unchanged tidal stretch.


Asunto(s)
Pulmón/fisiopatología , Surfactantes Pulmonares/metabolismo , Lesión Pulmonar Inducida por Ventilación Mecánica/fisiopatología , Resistencia de las Vías Respiratorias/fisiología , Animales , Citocinas/metabolismo , Elasticidad , Pulmón/metabolismo , Pulmón/patología , Rendimiento Pulmonar/fisiología , Fosfolípidos/metabolismo , Respiración con Presión Positiva , Distribución Aleatoria , Ratas , Respiración Artificial , Mecánica Respiratoria/fisiología , Volumen de Ventilación Pulmonar , Lesión Pulmonar Inducida por Ventilación Mecánica/metabolismo , Lesión Pulmonar Inducida por Ventilación Mecánica/patología
3.
Molecules ; 22(2)2017 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-28146132

RESUMEN

Tafluprost (AFP-168, 5) is a unique 15-deoxy-15,15-difluoro-16-phenoxy prostaglandin F2α (PGF2α) analog used as an efficacious ocular hypotensive agent in the treatment of glaucoma and ocular hypertension, as monotherapy, or as adjunctive therapy to ß-blockers. A novel convergent synthesis of 5 was developed employing Julia-Lythgoe olefination of the structurally advanced prostaglandin phenylsulfone 16, also successfully applied for manufacturing of pharmaceutical grade latanoprost (2), travoprost (3) and bimatoprost (4), with an aldehyde ω-chain synthon 17. The use of the same prostaglandin phenylsulfone 16, as a starting material in parallel syntheses of all commercially available antiglaucoma PGF2α analogs 2-5, significantly reduces manufacturing costs resulting from its synthesis on an industrial scale and development of technological documentation. Another key aspect of the route developed is deoxydifluorination of a trans-13,14-en-15-one 30 with Deoxo-Fluor. Subsequent hydrolysis of protecting groups and final esterification of acid 6 yielded tafluprost (5). The main advantages are the preparation of high purity tafluprost (5) and the application of comparatively cheap reagents. The preparation and identification of two other tafluprost acid derivatives, tafluprost methyl ester (32) and tafluprost ethyl amide (33), are also described.


Asunto(s)
Antihipertensivos/síntesis química , Técnicas de Química Sintética , Prostaglandinas F/síntesis química , Antihipertensivos/farmacología , Dinoprost/química , Dinoprost/farmacología , Glaucoma/tratamiento farmacológico , Estructura Molecular , Hipertensión Ocular/tratamiento farmacológico , Prostaglandinas F/farmacología
4.
Molecules ; 22(8)2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28809817

RESUMEN

Two unknown impurities were observed during the process development for multigram-scale synthesis of eplerenone (Inspra®). The new process-related impurities were identified and fully characterized as the corresponding (7ß,11α,17α)-11-hydroxy- and (7α,11ß,17α)-9,11-dichloroeplerenone derivatives 12a and 13. Seven other known but poorly described in the literature eplerenone impurities, including four impurities A, B, C and E listed in the European Pharmacopoeia 8.4 were also detected, identified and fully characterized. All these contaminants result from side reactions taking place on the steroid ring C of the starting 11α-hydroxy-7α-(methoxycarbonyl)-3-oxo-17α-pregn-4-ene-21,17-carbolactone (12) and the key intermediate (7α,17α)-9(11)-enester 7, including epimerization of the C-7 asymmetric center, oxidation, dehydration, chlorination and lactonization. The impurities were isolated and/or synthesized and fully characterized by infrared spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR) and high-resolution mass spectrometry/electrospray ionization (HRMS/ESI). Their ¹H- and 13C-NMR signals were fully assigned. The molecular structures of the eight impurities, including the new (7ß,11α,17α)-11-hydroxy- and (7α,11ß,17α)-9,11-dichloroeplerenone related substances 12a and 13, were solved and refined using single-crystal X-ray diffraction (SCXRD). The full identification and characterization of these impurities should be useful for the quality control and the validation of the analytical methods in the manufacture of eplerenone.


Asunto(s)
Antihipertensivos/química , Contaminación de Medicamentos , Espironolactona/análogos & derivados , Cromatografía Líquida de Alta Presión , Eplerenona , Espectroscopía de Resonancia Magnética , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Infrarroja , Espironolactona/química
5.
Clin Immunol ; 151(1): 16-24, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24495857

RESUMEN

We have identified a marked over-representation of transcription factors controlling differentiation of T, B, myeloid and NK cells among the 110 MS genes now known to be associated with multiple sclerosis (MS). To test if the expression of these genes might define molecular subtypes of MS, we interrogated their expression in blood in three independent cohorts of untreated MS (from Sydney and Adelaide) or clinically isolated syndrome (CIS, from San Francisco) patients. Expression of the transcription factors (TF) controlling T and NK cell differentiation, EOMES, TBX21 and other TFs was significantly lower in MS/CIS compared to healthy controls in all three cohorts. Expression was tightly correlated between these TFs, with other T/NK cell TFs, and to another downregulated gene, CCL5. Expression was stable over time, but did not predict disease phenotype. Optimal response to therapy might be indicated by normalization of expression of these genes in blood.


Asunto(s)
Esclerosis Múltiple/genética , Proteínas de Dominio T Box/genética , Adolescente , Adulto , Anciano , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos B/patología , Estudios de Casos y Controles , Diferenciación Celular , Quimiocina CCL5/genética , Quimiocina CCL5/inmunología , Estudios de Cohortes , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Células Asesinas Naturales/patología , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/patología , Transducción de Señal , Proteínas de Dominio T Box/inmunología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Linfocitos T/patología
6.
Mult Scler ; 20(6): 675-85, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24126065

RESUMEN

BACKGROUND: Multiple Sclerosis (MS) is an immune-mediated disease of the central nervous system which responds to therapies targeting circulating immune cells. OBJECTIVE: Our aim was to test if the T-cell activation gene expression pattern (TCAGE) we had previously described from whole blood was replicated in an independent cohort. METHODS: We used RNA-seq to interrogate the whole blood transcriptomes of 72 individuals (40 healthy controls, 32 untreated MS). A cohort of 862 control individuals from the Brisbane Systems Genetics Study (BSGS) was used to assess heritability and seasonal expression. The effect of interferon beta (IFNB) therapy on expression was evaluated. RESULTS: The MS/TCAGE association was replicated and rationalized to a single marker, ribosomal protein S6 (RPS6). Expression of RPS6 was higher in MS than controls (p<0.0004), and lower in winter than summer (p<4.6E-06). The seasonal pattern correlated with monthly UV light index (R=0.82, p<0.002), and was also identified in the BSGS cohort (p<0.0016). Variation in expression of RPS6 was not strongly heritable. RPS6 expression was reduced by IFNB therapy. CONCLUSIONS: These data support investigation of RPS6 as a potential therapeutic target and candidate biomarker for measuring clinical response to IFNB and other MS therapies, and of MS disease heterogeneity.


Asunto(s)
Factores Inmunológicos/uso terapéutico , Interferón beta/uso terapéutico , Esclerosis Múltiple/metabolismo , ARN Mensajero/sangre , Proteína S6 Ribosómica/metabolismo , Estaciones del Año , Adulto , Biomarcadores/análisis , Regulación hacia Abajo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/tratamiento farmacológico , ARN/genética , Adulto Joven
7.
Chirality ; 25(3): 170-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23381781

RESUMEN

The 17-phenyl PGF(2α) analogue bimatoprost (10a) is the most efficacious ocular hypotensive agent currently available for the treatment of glaucoma or ocular hypertension. A novel convergent synthesis of 13,14-en-15-ol prostamideF(2α) analogues was developed employing Julia-Lythgoe olefination of the structurally advanced phenylsulfone (+)-(5Z)-15 with an enantiomerically pure aldehyde ω-chain synthon (-)-(S)-16a. Subsequent hydrolysis of protecting groups and final amidation of the diol 26a yielded bimatoprost (10a). The main advantage of the current strategy is the preparation of high-purity bimatoprost (10a). The novel convergent strategy allows the synthesis of a whole series of 13,14-en-15-ol prostamideF(2α) analogues with the desired C-15 asymmetric center configuration from a common and structurally advanced prostaglandin intermediate (+)-(5Z)-15. The preparation and identification of two synthetic impurities, 15-epi isomer (10b) of bimatoprost and a new prostaglandin related amide (+)-(5Z)-18, are also described.


Asunto(s)
Amidas/síntesis química , Cloprostenol/análogos & derivados , Dinoprost/análogos & derivados , Dinoprost/síntesis química , Amidas/química , Bimatoprost , Cloprostenol/síntesis química , Cloprostenol/química , Glaucoma/tratamiento farmacológico , Estructura Molecular
8.
J Pediatr Hematol Oncol ; 34(4): e142-4, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22258346

RESUMEN

Rhabdomyolysis refers to a number of clinical and biochemical symptoms, which result from the destruction of skeletal muscles. The following triad of symptoms is considered typical: myalgia, muscle weakness, and dark urine. The most common reasons for rhabdomyolysis in children are infections. It has also been reported that rhabdomyolysis may be caused by chemotherapy drugs. The most difficult complication of rhabdomyolysis is renal failure. The authors present a 17-year-old boy diagnosed with Ewing sarcoma and a 16-year-old boy suffering from acute leukemia, both with rhabdomyolysis developed in the course of infection caused by Clostridium difficile, and drug-induced neutropenia.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Clostridioides difficile , Enterocolitis Seudomembranosa , Neutropenia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Rabdomiólisis , Sarcoma de Ewing/tratamiento farmacológico , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Enterocolitis Seudomembranosa/inducido químicamente , Enterocolitis Seudomembranosa/diagnóstico , Enterocolitis Seudomembranosa/patología , Enterocolitis Seudomembranosa/terapia , Humanos , Masculino , Neutropenia/inducido químicamente , Neutropenia/diagnóstico , Neutropenia/microbiología , Neutropenia/patología , Neutropenia/terapia , Rabdomiólisis/inducido químicamente , Rabdomiólisis/diagnóstico , Rabdomiólisis/microbiología , Rabdomiólisis/patología , Rabdomiólisis/terapia
9.
Wiad Lek ; 62(3): 149-52, 2009.
Artículo en Polaco | MEDLINE | ID: mdl-20229709

RESUMEN

INTRODUCTION: Acute lymphoblastic leukemia (ALL) is the most common cancer in childhood. Immunodeficiency occurs very often during ALL treatment. Therefore, patients are susceptible to various infections (including hepatitis B). MATERIAL AND METHODS: The study group consisted of 66 children with ALL treated at the Department of Pediatric, Hematology and Oncology in Zabrze. Patients were divided into two groups with regard to active HBV prophylaxis before diagnosis. Group I included 22 patients who were vaccinated before diagnosis. Group II included 44 patients who were not vaccinated before diagnosis. After diagnosis active, passive and/or active-passive prophylaxis were administered to the patients. RESULTS: In most patients, the anti-HBV titers were protective after ALL treatment completion. In the remaining children, with anti-HBV titers < 100 IU/ml, the HBV prophylaxis was also successful, because none of them experienced de novo HBV infection. CONCLUSIONS: Despite various models of HBV prophylaxis, the protection from new infection was effective in all children treated for ALL.


Asunto(s)
Hepatitis B/prevención & control , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicaciones , Adolescente , Niño , Preescolar , Femenino , Hepatitis B/etiología , Vacunas contra Hepatitis B/administración & dosificación , Humanos , Lactante , Masculino
10.
J Steroid Biochem Mol Biol ; 164: 66-71, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-26429396

RESUMEN

1,25-dihydroxyvitamin D3 (1,25D), a steroid hormone which regulates calcium/phosphate homeostasis, has a broad spectrum of anti-cancer activities, including differentiation of acute myeloid leukemia (AML) cells. In order to avoid undesirable side effects such as hypercalcemia, low-calcemic analogues should be produced for therapeutic purposes. In this paper, we describe biological activities of double-point modified analogues of vitamin D2 and we compare them to 1,25D and to paricalcitol, the drug used to treat secondary hyperparathyroidism. In vivo, our new analogues have lower calcemic effects, and lower toxicity in comparison to 1,25D. They have enhanced pro-differentiating and transcription-inducing activities in AML cells. Interestingly, differentiation effects do not correlate with the affinities of the analogues to the vitamin D receptor (VDR).


Asunto(s)
Ergocalciferoles/química , Ergocalciferoles/síntesis química , Transporte Activo de Núcleo Celular , Animales , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Diferenciación Celular , Evaluación Preclínica de Medicamentos , Ergocalciferoles/genética , Células HL-60 , Homeostasis , Humanos , Hipercalcemia/metabolismo , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Receptores de Lipopolisacáridos/metabolismo , Ratones , Mutación Puntual , Receptores de Calcitriol/metabolismo , Activación Transcripcional/efectos de los fármacos , Regulación hacia Arriba , Vitamina D3 24-Hidroxilasa/metabolismo
11.
Steroids ; 78(10): 1003-14, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23811018

RESUMEN

The hybrid analogs of 1,25-dihydroxyergocalciferol (PRI-5201 and PRI-5202) were synthesized as potential anticancer agents using a convergent strategy. The analogs were designed by combining a 19-nor modification of the A-ring with the homologated and rigidified ergocalciferol-like side-chain of the previously obtained analogs PRI-1906 and PRI-1907. The strategy also allowed the novel efficient synthesis of 19-nor-1,25-dihydroxyergocalciferol (paricalcitol, PRI-5100) and its (24R)-diastereomer (PRI-5101). The single crystal X-ray structures of the 19-nor analogs (PRI-5100 and PRI-5101) were solved and refined. The A-ring of both analogs adopts exclusively chair ß-conformation in the solid state. The side-chain of these analogs is coplanar with the CD-ring plane, while it is perpendicular in 1,25-dihydroxycholecalciferol.


Asunto(s)
Antineoplásicos/síntesis química , Ergocalciferoles/síntesis química , Antineoplásicos/química , Cristalografía por Rayos X , Ergocalciferoles/química , Enlace de Hidrógeno , Modelos Moleculares , Conformación Molecular , Oxidación-Reducción
12.
J Pharm Sci ; 102(11): 3925-31, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23946154

RESUMEN

As predicted by single crystal X-ray crystallography, and contrary to the reported suggestions, the anhydrous form of calcipotriol, a therapeutically important vitamin D analog, was found stable enough to be used as an active pharmaceutical ingredient. The crystal and molecular structure of calcipotriol anhydrate was solved and refined using single crystal X-ray diffraction. The analog was obtained by a novel convergent synthesis from the vitamin D C-22 sulfone, as an advanced intermediate and a side-chain fragment. The homo-chiral side-chain aldehyde was obtained from cyclopropanecarboxyaldehyde by the chromatographic separation of the intermediate diastereomeric salts with (S)-naproxen. Calcipotriol anhydrate showed a single peak in differential scanning calorimetry and the absence of a peak from a water molecule, typical for the monohydrate. Calcipotriol anhydrate, as the only 1,25-dihydroxylated analog of vitamin D3 , exists as a mixture of both α- and ß-forms of the A-ring, present in the asymmetric part of the unit cell of the crystal lattice. The intermolecular hydrogen bonding between both conformers in the crystal lattice indicated that the stability of calcipotriol anhydrate might be at least the same as for the known monohydrate. The usefulness of calcipotriol anhydrate as an active pharmaceutical ingredient was confirmed by the stability study in the standard conditions used for the storage of vitamin D analogs.


Asunto(s)
Calcitriol/análogos & derivados , Vitamina D/análogos & derivados , Vitaminas/química , Agua/química , Calcitriol/síntesis química , Calcitriol/química , Rastreo Diferencial de Calorimetría , Cristalografía por Rayos X , Estabilidad de Medicamentos , Modelos Moleculares , Vitamina D/síntesis química , Vitamina D/química , Vitaminas/síntesis química
13.
Cancers (Basel) ; 5(4): 1355-78, 2013 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-24202449

RESUMEN

Diastereomeric and geometric analogs of calcipotriol, PRI-2202 and PRI-2205, were synthesized as advanced intermediates from vitamin D C-22 benzothiazoyl sulfones and side-chain aldehydes using our convergent strategy. Calcitriol, calcipotriol (PRI-2201) and tacalcitol (PRI-2191) were used as the reference compounds. Among a series of tested analogs the diastereomeric analog PRI-2202 showed the strongest antiproliferative activity on the human breast cancer cell line MCF-7, whereas the geometric analog PRI-2205 was the weakest. Both analogs were less potent in antiproliferative activity against HL-60 cells compared to the reference compounds. The ability to potentiate antiproliferative effect of cisplatin or doxorubicin against HL-60 cells or that of tamoxifen against the MCF-7 cell line was observed at higher doses of PRI-2202 or PRI-2205 than those of the reference compounds. The proapoptotic activity of tamoxifen, expressed as the diminished mitochondrial membrane potential, as well as the increased phosphatidylserine expression, was partially attenuated by calcitriol, PRI-2191, PRI-2201 and PRI-2205. The treatment of the MCF-7 cells with tamoxifen alone resulted in an increase in VDR expression. Moreover, a further increase in VDR expression was observed when the analogs PRI-2201 or PRI-2205, but not PRI-2191, were used in combination with tamoxifen. This observation could partially explain the potentiation of the antiproliferative effect of tamoxifen by vitamin D analogs.

14.
Med J Aust ; 190(6): 334-6, 2009 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-19296818

RESUMEN

A 32-year-old woman with a 4-year history of multiple sclerosis presented with persistent clawing of the right hand. History revealed that she and five family members had lifelong symptoms of paradoxical myotonia (impaired relaxation of muscles following muscle contraction), exacerbated by cold. The family was diagnosed with paramyotonia congenita, based on neurophysiological and genetic studies. To our knowledge, this is the first report of an Australian family with paramyotonia congenita.


Asunto(s)
Trastornos Miotónicos/genética , Linaje , Canales de Sodio/genética , Adulto , Femenino , Humanos , Mutación , Trastornos Miotónicos/diagnóstico , Trastornos Miotónicos/fisiopatología , Canal de Sodio Activado por Voltaje NAV1.4 , Canales de Sodio/fisiología
15.
Biol Reprod ; 69(6): 2022-8, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12930727

RESUMEN

Bovine ovarian antral follicles exhibit either one or the other of two patterns of granulosa cell death in atresia. Death can commence either from the antrum and progress toward the basal lamina (antral atresia) or the converse (basal atresia). In basal atresia, the remaining live antrally situated cells appeared to continue maturing. Beyond that, little is known about these distinct patterns of atresia. Healthy (nonatretic) follicles also exhibit either one or the other of two patterns of granulosa cell shape, follicular basal lamina ultrastructure or location of younger cells within the membrana granulosa. To examine these different phenotypes, the expression of the steroidogenic enzymes cholesterol side-chain cleavage cytochrome P450 (SCC) and 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in granulosa cells and concentrations of steroid hormones in follicular fluid were measured in individual histologically classified bovine antral follicles. Healthy follicles first expressed SCC and 3beta-HSD in granulosa cells only when the follicles reached an approximate threshold of 10 mm in diameter. The pattern of expression in antral atretic follicles was the same as healthy follicles. Basal atretic follicles were all <5 mm. In these, the surviving antral granulosa cells expressed SCC and 3beta-HSD. In examining follicles of 3-5 mm, basal atretic follicles were found to have substantially elevated progesterone (P < 0.001) and decreased androstenedione and testosterone compared to healthy and antral atretic follicles. Estradiol was highest in the large healthy follicles, lower in the small healthy follicles, lower still in the antral atretic follicles, and lowest in the basal atretic follicles. Our findings have two major implications. First, the traditional method of identifying atretic follicles by measurement of steroid hormone concentrations may be less valid with small bovine follicles. Second, features of the two forms of follicular atresia are so different as to imply different mechanisms of initiation and regulation.


Asunto(s)
3-Hidroxiesteroide Deshidrogenasas/metabolismo , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/metabolismo , Líquido Folicular/metabolismo , Folículo Ovárico/metabolismo , Esteroides/metabolismo , Androstenodiona/metabolismo , Animales , Bovinos , Estradiol/metabolismo , Femenino , Atresia Folicular , Folículo Ovárico/patología , Folículo Ovárico/fisiología , Progesterona/metabolismo , Valores de Referencia , Testosterona/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA