RESUMEN
As the organ shortage continues to grow, the creation of social media communities by transplant hospitals and the public is rapidly expanding to increase the number of living donors. Social media communities are arranged in myriad ways and without standardization, raising concerns about transplant candidates' and potential donors' autonomy and quality of care. Social media communities magnify and modify extant ethical issues in deceased and living donation related to privacy, confidentiality, professionalism, and informed consent, and increase the potential for undue influence and coercion for potential donors and transplant candidates. Currently, no national ethical guidelines have been developed in the United States regarding the use of social media to foster organ transplantation. We provide an ethical framework to guide transplant stakeholders in using social media for public and patient communication about transplantation and living donation, and offer recommendations for transplant clinical practice and future research.
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Consentimiento Informado/ética , Donadores Vivos , Trasplante de Órganos , Educación del Paciente como Asunto , Guías de Práctica Clínica como Asunto/normas , Medios de Comunicación Sociales , Obtención de Tejidos y Órganos/ética , Humanos , Estados UnidosRESUMEN
New approaches to address the kidney scarcity in the United States are urgently needed. The greatest potential source of kidneys is from living donors. Proposals to offer financial incentives to increase living kidney donation rates remain highly controversial. Despite repeated calls for a pilot study to assess the impact of financial compensation on living kidney donation rates, many fear that financial incentives will exploit vulnerable individuals and cast the field of transplantation in a negative public light, ultimately reducing donation rates. This paper provides an ethical justification for conducting a pilot study of a federally regulated approach to providing financial incentives to living kidney donors, with the goal of assessing donors' perceptions.
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Trasplante de Riñón/métodos , Donadores Vivos/ética , Motivación , Nefrectomía/economía , Insuficiencia Renal/cirugía , Obtención de Tejidos y Órganos/economía , Ética Médica , Humanos , Trasplante de Riñón/economía , Trasplante de Riñón/ética , Relaciones Médico-Paciente , Proyectos Piloto , Proyectos de Investigación , Recolección de Tejidos y Órganos/economía , Recolección de Tejidos y Órganos/ética , Obtención de Tejidos y Órganos/ética , Estados Unidos , Poblaciones VulnerablesRESUMEN
There are no minimally invasive diagnostic metrics for acute kidney transplant rejection (AR), especially in the setting of the common confounding diagnosis, acute dysfunction with no rejection (ADNR). Thus, though kidney transplant biopsies remain the gold standard, they are invasive, have substantial risks, sampling error issues and significant costs and are not suitable for serial monitoring. Global gene expression profiles of 148 peripheral blood samples from transplant patients with excellent function and normal histology (TX; n = 46), AR (n = 63) and ADNR (n = 39), from two independent cohorts were analyzed with DNA microarrays. We applied a new normalization tool, frozen robust multi-array analysis, particularly suitable for clinical diagnostics, multiple prediction tools to discover, refine and validate robust molecular classifiers and we tested a novel one-by-one analysis strategy to model the real clinical application of this test. Multiple three-way classifier tools identified 200 highest value probesets with sensitivity, specificity, positive predictive value, negative predictive value and area under the curve for the validation cohort ranging from 82% to 100%, 76% to 95%, 76% to 95%, 79% to 100%, 84% to 100% and 0.817 to 0.968, respectively. We conclude that peripheral blood gene expression profiling can be used as a minimally invasive tool to accurately reveal TX, AR and ADNR in the setting of acute kidney transplant dysfunction.
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Biomarcadores/sangre , Perfilación de la Expresión Génica , Rechazo de Injerto/sangre , Rechazo de Injerto/clasificación , Fallo Renal Crónico/cirugía , Trasplante de Riñón , Complicaciones Posoperatorias/genética , Adulto , Área Bajo la Curva , Reacciones Falso Negativas , Femenino , Estudios de Seguimiento , Rechazo de Injerto/etiología , Humanos , Fallo Renal Crónico/complicaciones , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Complicaciones Posoperatorias/sangre , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
The objective of this study was to determine whether the inclusion of garlic in a ration would have a negative impact on the flavour of lamb. The study used meat from 31 Merino wether lambs fed diets with varying levels of garlic (0%, 1.8% and 3.6%) for 10 weeks. Cooked samples of meat from the lambs were assessed for flavour and acceptability as lamb by an untrained consumer panel. There was no difference (P>0.05) between the treatments in flavour score, but the 3.6% garlic treatment group scored significantly higher in terms of acceptability as lamb (P<0.05) and was commented on positively by the panellists more frequently than the meat from any other treatment (P<0.05). These results suggest that the inclusion of garlic into the animals' feed did not have a negative impact on the flavour of the lamb and, at the high rate (3.6%), made the meat more acceptable to the panellists.
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Alimentación Animal , Ajo , Carne/análisis , Sensación , Adulto , Animales , Australia , Preferencias Alimentarias , Hemoncosis/prevención & control , Hemoncosis/veterinaria , Humanos , Masculino , Control de Calidad , Ovinos , Enfermedades de las Ovejas/prevención & control , Oveja Doméstica , GustoRESUMEN
AIM: Ataxia telangiectasia mutated (ATM) reportedly plays a role in insulin-stimulated activation of Akt in some cell types but not in others. The role of ATM in insulin signalling has not been firmly resolved for skeletal muscle cells, for which Akt phosphorylation is a pivotal step in stimulation of glucose transport. Accordingly, our aim was to determine the role of ATM in insulin effects for cell lines derived from skeletal muscle and for skeletal muscle. METHODS: We examined insulin effects in L6 myotubes, mouse soleus, C2C12 myotubes and differentiated rhabdomyosarcoma (RD) cells in the presence and absence of a low concentration (1 microm) of the ATM inhibitor KU55933. We also compared insulin signalling in C2C12 cells expressing shRNA against ATM and control cell lines (empty vector; cells expressing non-targeting shRNA). RESULTS: In L6 myotubes and mouse soleus muscle, KU55933 inhibited insulin-stimulated phosphorylation of the 160 kDa substrate of Akt (AS160) despite no effect on Akt. In contrast, KU55933 prevented insulin-stimulated Akt phosphorylation in C2C12 myotubes. Furthermore, C2C12 myotubes expressing shRNA against ATM displayed reduced insulin-stimulated Akt phosphorylation compared to controls. KU55933 also decreased insulin-stimulated Akt phosphorylation in differentiated RD cells. CONCLUSION: These model-dependent differences in the role of ATM in insulin action demonstrate a role of ATM in insulin-stimulated phosphorylation of Akt (in C2C12 and RD cells) but also allow the elucidation of a novel, Akt-independent role of ATM (in L6 myotubes and mouse soleus, at the level of AS160) in insulin signalling.
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Ataxia Telangiectasia/genética , Glucosa/fisiología , Insulina/genética , Contracción Muscular/fisiología , Músculo Esquelético/fisiología , Proteínas Proto-Oncogénicas c-akt/fisiología , Transducción de Señal/fisiología , Animales , Ataxia Telangiectasia/fisiopatología , Transporte Biológico/fisiología , Transportador de Glucosa de Tipo 4 , Insulina/fisiología , Ratones , Células Musculares , Fibras Musculares Esqueléticas , Mutación , Fosforilación/efectos de los fármacos , Fosforilación/fisiología , Transducción de Señal/genéticaRESUMEN
There seems to be an association between increased concentrations of malonyl coenzyme A (malonyl CoA) in skeletal muscle and diabetes and/or insulin resistance. The purpose of the current study was to test the hypothesis that treatments designed to manipulate malonyl CoA concentrations would affect insulin-stimulated glucose transport in cultured C2C12 myotubes. We assessed glucose transport after polyamine-mediated delivery of malonyl CoA to myotubes, after incubation with dichloroacetate (which reportedly increases malonyl CoA levels), or after exposure of myotubes to 2-bromopalmitate, a carnitine palmitoyl transferase I inhibitor. All three of these treatments prevented stimulation of glucose transport by insulin. We also assayed glucose transport after 30 min of inhibition of acetyl coenzyme A carboxylase (ACC), the enzyme which catalyzes the production of malonyl CoA. Three unrelated ACC inhibitors (diclofop, clethodim, and Pfizer CP-640186) all enhanced insulin-stimulated glucose transport. However, none of the treatments designed to manipulate malonyl CoA concentrations altered markers of proximal insulin signaling through Akt. The findings support the hypothesis that acute changes in malonyl CoA concentrations affect insulin action in muscle cells but suggest that the effects do not involve alterations in proximal insulin signaling.
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Glucosa/metabolismo , Insulina/fisiología , Malonil Coenzima A/fisiología , Fibras Musculares Esqueléticas/enzimología , Animales , Transporte Biológico Activo/efectos de los fármacos , Transporte Biológico Activo/fisiología , Bovinos , Línea Celular , Ácido Dicloroacético/farmacología , Ratones , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/metabolismoRESUMEN
The hypothesis of the Testicular Dysgenesis Syndrome (TDS), first suggested in 2001, propose that several disorders of the male reproductive system such as infertility, hypospadias, cryptorchidism and testicular cancer are all symptoms of TDS, which is most likely initiated during early foetal development, and may be provoked by external factors such as endocrine disruptors in addition to genetic predisposition. Testicular germ cell tumours (TGCTs), considered the most severe symptom of TDS, have increased in incidence during the last 60 years, to become the most common malignancy in young Caucasian men aged 17-45 years. TGCTs of young men originate from carcinoma in situ (CIS) cells. In the last few years, progress has been made identifying candidate genes involved in the neoplastic development of CIS, which may elucidate the timing of the initiation of CIS, currently thought to originate in foetal life from primordial germ cells or early gonocytes. Histological dysgenetic features are frequently seen in testes affected with the TDS components testis cancer or cryptorchidism. A TDS-like phenotype can be induced in male rats by in utero exposure to high concentrations of dibutyl phthalate (DBP) suggesting that ubiquitously present environmental endocrine disruptors may play a role in the aetiology of human TDS. So far, no animal model has been able to mimick all the symptoms of TDS including TGCTs although CIS-like cells have been found in a spontaneous testicular neoplasm in a rabbit.
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Carcinoma in Situ/patología , Disgenesia Gonadal/patología , Poliploidía , Enfermedades Testiculares/patología , Neoplasias Testiculares/patología , Adolescente , Adulto , Carcinoma in Situ/etiología , Carcinoma in Situ/genética , Aberraciones Cromosómicas , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Testiculares/etiología , Neoplasias Testiculares/genéticaRESUMEN
In this study we evaluated the effect of manipulating the estrogen and androgen environment of the neonatal male rat on subsequent immunoexpression of sex steroid receptors in the seminal vesicles (SVs) at age 18 days. The aim was to establish to what extent such changes were associated with and predictive of changes in SV structure/composition. Treatments were either diethylstilbestrol (DES; 10, 1, or 0.1 microg/injection), ethinyl estradiol (EE; 10 microg/injection), tamoxifen (2 mg/kg/day), flutamide (50 mg/kg), a gonadotropin-releasing hormone antagonist (GnRHa; 10 mg/kg), genistein (4 mg/kg/day), octylphenol (2 mg/injection), or bisphenol A (0.5 mg/injection). Compared with controls, treatment with DES (10 microg) induced loss of epithelial and stromal androgen receptor (AR) immunoexpression coincident with induction of stromal progesterone receptor (PR) immunoexpression and upregulation of stromal immunoexpression of estrogen receptor-alpha (ERalpha). These changes were associated with gross distortion (increase) of the normal stromal:epithelial tissue proportions in the SVs. DES (1 microg) and EE induced similar but less pronounced changes, and DES (0.1 microg) had no noticeable effect. Tamoxifen and flutamide induced PR and slightly upregulated ERalpha immunoexpression but had only a minor or no effect on AR expression and the stromal:epithelial ratio, though flutamide retarded normal development of the SVs. The latter was also evident in GnRHa-treated males, but otherwise this treatment had no effect on AR and PR immunoexpression. None of the foregoing treatments had any detectable effect on the immunoexpression of ERss in stromal or epithelial cells. The major treatment-induced changes in immunoexpression of AR, PR, and ERalpha and lack of change in ERss were confirmed by Western blots of SV protein extracts. None of the three weak (environmental) estrogens tested caused any detectable change in sex steroid receptor immunoexpression or SV tissue composition. We conclude that treatment-induced loss of AR is a prerequisite for altered stromal:epithelial proportions in the SVs and that such loss is always associated with induction of PR and upregulation of ERalpha; the latter two changes are insufficient on their own to bring about such a change. Nevertheless, induction of PR expression was always associated with altered SV development and is a potentially useful marker because it is not normally expressed in male reproductive tissues.
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Contaminantes Ambientales/efectos adversos , Estrógenos/farmacología , Regulación de la Expresión Génica , Receptores de Esteroides/biosíntesis , Vesículas Seminales/ultraestructura , Animales , Animales Recién Nacidos , Biomarcadores/análisis , Masculino , Ratas , Ratas Wistar , Vesículas Seminales/efectos de los fármacos , Regulación hacia ArribaRESUMEN
Estrogen receptor alpha (ER alpha) is essential for male fertility. Its activity is responsible for maintaining epithelial cytoarchitecture in efferent ductules and the reabsorption of fluid for concentrating sperm in the head of the epididymis. These discoveries and others have helped to establish estrogen's bisexual role in reproductive importance. Reported here is the molecular mechanism to explain estrogen's role in fluid reabsorption in the male reproductive tract. It is shown that estrogen regulates expression of the Na(+)/H(+) exchanger-3 (NHE3) and the rate of (22)Na(+) transport, sensitive to an NHE3 inhibitor. Immunohistochemical staining for NHE3, carbonic anhydrase II (CAII), and aquaporin-I (AQP1) was decreased in ER alpha knockout (alpha ERKO) efferent ductules. Targeted gene-deficient mice were compared with alpha ERKO, and the NHE3 knockout and CAII-deficient mice showed alpha ERKO-like fluid accumulation, but only the NHE3 knockout and alpha ERKO mice were infertile. Northern blot analysis showed decreases in mRNA for NHE3 in alpha ERKO and antiestrogen-treated mice. The changes in AQP1 and CAII in alpha ERKO seemed to be secondary because of the disruption of apical cytoarchitecture. Ductal epithelial ultrastructure was abnormal only in alpha ERKO mice. Thus, in the male, estrogen regulates one of the most important epithelial ion transporters and maintains epithelial morphological differentiation in efferent ductules of the male, independent of its regulation of Na(+) transport. Finally, these data raise the possibility of targeting ER alpha in developing a contraceptive for the male.
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Estradiol/análogos & derivados , Estrógenos/metabolismo , Fertilidad/fisiología , Intercambiadores de Sodio-Hidrógeno/fisiología , Sodio/metabolismo , Conducto Deferente/fisiología , Absorción , Animales , Acuaporina 1 , Acuaporinas/genética , Acuaporinas/metabolismo , Secuencia de Bases , Anhidrasa Carbónica II/metabolismo , ADN Complementario , Estradiol/farmacología , Antagonistas de Estrógenos/farmacología , Receptor alfa de Estrógeno , Fulvestrant , Expresión Génica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Datos de Secuencia Molecular , ARN , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Intercambiador 3 de Sodio-Hidrógeno , Intercambiadores de Sodio-Hidrógeno/genética , Intercambiadores de Sodio-Hidrógeno/metabolismo , Conducto Deferente/metabolismo , Agua/metabolismoRESUMEN
We postulated that high circulating cortisol levels during intense exercise would lead to increased serum leptin concentrations. Young, lean men ate a small meal and then exercised on a cycle ergometer for 41 min or rested on a control day. Serum leptin concentration was 10% greater during exercise than in the control condition (P < 0.05). Directly after exercise, serum leptin dropped to approximately 10% less than the control level (P < 0.05) but had recovered to the nonexercised level after approximately 2 h of recovery. Rapid exercise effects on circulating leptin were related to changes in hemoconcentration rather than changes in leptin mass. When serum leptin was normalized to serum protein, leptin increased by 10% in the exercise condition compared with control by the end of recovery (P < 0.05). Although exercise increased serum cortisol concentration threefold, there was no relation between differences in cortisol and exercise vs. control differences in normalized leptin. The increased leptin mass after exercise may have been related to greater plasma glucose concentration during recovery after exercise compared with the control condition.
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Ejercicio Físico/fisiología , Absorción Intestinal/fisiología , Leptina/sangre , Esfuerzo Físico/fisiología , Periodo Posprandial/fisiología , Adulto , Área Bajo la Curva , Glucemia/metabolismo , Índice de Masa Corporal , Ingestión de Alimentos/fisiología , Ayuno , Ácidos Grasos no Esterificados/sangre , Frecuencia Cardíaca , Humanos , Hidrocortisona/sangre , Insulina/sangre , Masculino , Consumo de Oxígeno , Factores de TiempoRESUMEN
The effects on reproductive tract development in male rats, of neonatal exposure to potent (reference) oestrogens, diethylstilboestrol (DES) and ethinyl oestradiol (EE), with those of two environmental oestrogens, octylphenol and hisphenol A were systematically compared. Other treatments, such as administration of a gonadotrophin-releasing hormone antagonist (GnRHa) or the anti-oestrogen tamoxifen or the anti-androgen flutamide, were used to aid interpretation of the pathways involved. All treatments were administered in the neonatal period before onset of puberty. The cellular sites of expression of androgen receptors (AR) and of oestrogen receptor-alpha (ERalpha) and ERbeta were also established throughout development of the reproductive system. The main findings were as follows: (i) all cell types that express AR also express one or both ERs at all stages of development; (ii) Sertoli cell expression of ERbeta occurs considerably earlier in development than does expression of AR; (iii) most germ cells, including fetal gonocytes, express ERbeta but not AR; (iv) treatment with high, but not low, doses of potent oestrogens such as DES and EE, induces widespread structural and cellular abnormalities of the testis and reproductive tract before puberty; (v) the latter changes are associated with loss of immunoexpression of AR in all affected tissues and a reduction in Leydig cell volume per testis; (vi) none of the effects in (iv) and (v) can be duplicated by treating with high-dose octylphenol or bisphenol A; (vi) none of the reproductive tract changes in (iv) and (v) can be induced by simply suppressing androgen production (GnRHa treatment) or action (flutamide treatment); and (vii) the adverse changes induced by high-dose DES (iv and v) can be largely prevented by co-administration of testosterone. Thus, it is suggested that many of the adverse changes to the testis and reproductive tract induced by exposure to oestrogens result from a combination of high oestrogen and low androgen action. High oestrogen action or low androgen action on their own are unable to induce the same changes.
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Anomalías Inducidas por Medicamentos , Animales Recién Nacidos/crecimiento & desarrollo , Exposición a Riesgos Ambientales , Estrógenos/farmacología , Genitales Masculinos/anomalías , Genitales Masculinos/efectos de los fármacos , Andrógenos/fisiología , Animales , Estrógenos/metabolismo , Masculino , RatasRESUMEN
OBJECTIVES: To examine the effects of testosterone (TST) loss on skeletal muscle contractile function and the potential interactive effects of TST loss and physical inactivity. DESIGN: Randomized control trial. ANIMALS: Forty-eight male rats (age, 6mo) were placed into control (Con) or gonadectomized (Orx) groups. INTERVENTION: Two weeks after Orx or sham surgery, half the Con and Orx rats were hind-limb unloaded (HLU) to reduce muscle activity for 2 weeks. Subsequently, in situ contractile function tests were performed on the soleus (SOL), plantaris (PLAN), peroneus longus (PER), and extensor digitorum longus (EDL). These 4 muscles and gastrocnemius (GAST) then were removed, weighed, sectioned, and stained with adenosine triphosphatase for fiber typing and fiber area measures. MAIN OUTCOME MEASURES: Peak tetanic tension (P(0)), time to peak twitch contraction (TPT), half relaxation time (RT(1/2)), muscle mass, fiber area, and specific tension (ratio of P(0)/muscle mass). RESULTS: Body weight and muscle mass were similar in the Con and Orx groups. The ratio of P(0) to muscle mass was significantly (p <.05) reduced with Orx in SOL (20%), PLAN (18%), PER (28%), and EDL (20%). TPT and RT(1/2) were significantly faster after Orx in PLAN, PER, and EDL. HLU significantly reduced muscle mass in SOL, PLAN, and GAST in Orx and intact groups. HLU also caused a significant decline in SOL and PLAN P(0). The loss in P(0) in the Orx-HLU rats was no greater than the decline in P(0) with HLU alone. CONCLUSIONS: Gonadectomy results in a loss of P(0) regardless of muscle fiber type or function, it is likely to speed up TPT and RT(1/2), and it does not exacerbate HLU-related atrophy and P(0) loss. Findings may have implications for men with reduced TST levels, as in aging, for instance.
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Castración , Contracción Muscular/fisiología , Músculo Esquelético/fisiología , Testosterona/farmacología , Análisis de Varianza , Animales , Atrofia , Inmovilización , Masculino , Ratas , Ratas Sprague-Dawley , Pérdida de PesoRESUMEN
This study evaluated whether androgen action is altered in rats treated neonatally with diethylstilbestrol (DES) at a dose that induced reproductive tract abnormalities. Rats were treated on alternate days 2-12 with 10 microg DES and studied on Day 18. DES-induced abnormalities included a 70% reduction in testis weight, distension and overgrowth of the rete, distension and reduction in epithelial height of the efferent ducts, underdevelopment of the epididymal duct epithelium, reduction in epithelial height in the vas deferens, and convolution of the extra-epididymal vas. In DES-treated rats, androgen receptor (AR) immunoexpression was virtually absent from all affected tissues and the testis, whereas AR expression in controls was intense in epithelial and stromal cells. The DES-induced change in AR immunoexpression was confirmed by Western analysis for the testis. In rats treated neonatally with 1 microg DES, reproductive abnormalities were absent or minor, except for a 38% reduction in testis weight; loss of AR immunoexpression also did not occur in these rats. Treatment-induced changes in AR expression were paralleled by changes in Leydig cell volume per testis (91% reduction in the 10-microg DES group; no change in the 1-microg DES group). To test whether suppression of androgen production or action alone could induce comparable reproductive abnormalities to 10 microg DES, rats were treated neonatally with either a potent gonadotropin-releasing hormone antagonist (GnRHa) or with flutamide (50 mg/kg/day). These treatments reduced testis weight (68% for GnRHa, 40% for flutamide), and generally retarded development of the reproductive tract but failed to induce the abnormalities induced by 10 microg DES. GnRHa and flutamide caused no detectable change in AR immunoexpression in target tissues, with the exception of minor changes in the testes of flutamide-treated males. GnRHa treatment caused a reduction (83%) in Leydig cell volume comparable to that caused by 10 microg DES. Immunoexpression of estrogen receptor alpha (ER alpha) in the efferent ducts and of ER beta in all tissues studied were unaffected by any of the above treatments. Neonatal coadministration of testosterone esters (TE; 200 microg) with 10 microg DES prevented most of the morphological abnormalities induced by 10 microg DES treatment alone, though testis weight was still subnormal (46% reduction in DES + TE vs 72% in DES alone and 49% with TE alone) and some lumenal distension was still evident in the efferent ducts. Coadministration of TE with DES prevented DES-induced loss of AR immunoexpression (confirmed for testis by Western blot analysis). It is concluded that 1) reproductive tract abnormalities induced in the neonatal male rat by a high (10 microg) dose of DES are associated with reduced AR expression and Leydig cell volume; 2) these changes are largely absent with a lower dose of DES (1 microg); 3) treatments that interfere with androgen production (GnRHa) or action (flutamide) alone failed to induce reproductive tract abnormalities or alter AR expression as did 10 microg DES; 4) a grossly altered androgen:estrogen balance (low androgen + high estrogen) may underlie the reproductive tract abnormalities, other than reduced testis weight, induced by high doses of DES.
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Antagonistas de Andrógenos/farmacología , Andrógenos/fisiología , Animales Recién Nacidos , Dietilestilbestrol/efectos adversos , Genitales Masculinos/efectos de los fármacos , Animales , Western Blotting , Relación Dosis-Respuesta a Droga , Genitales Masculinos/anomalías , Inmunohistoquímica , Masculino , Ratas , Ratas WistarRESUMEN
This study in rats sought to 1) characterize immunoexpression of estrogen receptor alpha (ERalpha) and ERss in the efferent ducts, epididymis, and vas deferens during postnatal development; 2) establish whether ER expression changed after neonatal treatment with diethylstilbestrol (DES); and 3) determine whether ER changes coincided with abnormal epididymal/vas development. Rats were administered 10 microg DES or vehicle on days 2, 4, 6, 8, 10, and 12 and were sampled on days 10, 18, 25, 35, and 90+. At all ages, ERalpha was immunoexpressed intensely in the efferent ducts. On day 10, immunoexpression of ERalpha was absent from the epididymis and vas, but was detectable on day 18 in epithelial cells in the caput, corpus, and proximal cauda. Epithelial expression of ERalpha was absent from the distal cauda and in the proximal and distal vas was confined to a band of periductal stromal cells. Thus, on day 18, the site of ERalpha expression delineated the epididymis-vas boundary. On days 25-35, epithelial expression of ERalpha was absent, but stromal expression persisted in the vas and distal cauda. In adults, immunoexpression of ERalpha in the epididymis and vas was absent. In contrast, ERbeta was immunoexpressed in epithelial cells and some stromal cells in the efferent ducts, epididymis, and vas at all ages. In the vas, stromal expression of ERalpha and ERbeta was in different layers. DES treatment caused 1) underdevelopment of the epididymal duct and reduced epithelial height in epididymis and vas; 2) coiling of the extraepididymal vas; 3) thickening of the periductal actin-free stromal layer in the distal cauda and vas; and 4) reduced cell proliferation on day 18 in the epididymis and vas, based on incorporation of bromodeoxyuridine, especially in the epithelium. These changes coincided with abnormalities in cell- and region-specific immunoexpression of ERalpha, but not ERbeta. Thus, in DES-treated rats on day 18, epithelial expression of ERalpha occurred in all regions of the epididymis and vas instead of being confined to the caput, corpus, and proximal cauda as in controls. Similarly, stromal ERalpha expression in the vas of DES-treated rats was not confined to a periductal layer as in controls, but occurred diffusely in the muscle layer. It is suggested that 1) estrogens play a role in peripubertal development of the epididymis and vas; 2) the cellular site of expression of ERalpha either plays a role in or reflects demarcation of the epididymal/vas boundary; and 3) blurring of this boundary in DES-treated rats coincides with altered ERalpha immunoexpression.
Asunto(s)
Envejecimiento/metabolismo , Animales Recién Nacidos/metabolismo , Dietilestilbestrol/farmacología , Epidídimo/metabolismo , Estrógenos no Esteroides/farmacología , Receptores de Estrógenos/metabolismo , Conducto Deferente/metabolismo , Animales , Animales Recién Nacidos/crecimiento & desarrollo , División Celular/efectos de los fármacos , Epidídimo/efectos de los fármacos , Epidídimo/crecimiento & desarrollo , Epidídimo/patología , Receptor alfa de Estrógeno , Receptor beta de Estrógeno , Inmunohistoquímica , Masculino , Ratas , Ratas Wistar , Distribución Tisular , Conducto Deferente/efectos de los fármacos , Conducto Deferente/crecimiento & desarrollo , Conducto Deferente/patologíaRESUMEN
This study investigated whether neonatal exposure of male rats to estrogenic compounds altered pubertal spermatogenesis (days 18 and 25) and whether the changes observed resulted in long-term changes in testis size, mating, or fertility (days 90-100). Rats were treated neonatally with a range of doses (0.01-10 microg) of diethylstilbestrol (DES; administered on alternate days from days 2-12), a high dose of octylphenol (OP; 2 mg administered daily from days 2-12) or bisphenol A (Bis-A; 0.5 mg administered daily from days 2-12), or vehicle, while maintained on a standard soy-containing diet. The effect on the same parameters of rearing control animals on a soy-free diet was also assessed as was the effect of administering such animals genistein (4 mg/kg/day daily from days 2-18). Testis weight, seminiferous tubule lumen formation, the germ cell apoptotic index (apoptotic/viable germ cell nuclear volume), and spermatocyte nuclear volume per unit Sertoli cell nuclear volume were used to characterize pubertal spermatogenesis. Compared with (soy-fed) controls, DES administration caused dose-dependent retardation of pubertal spermatogenesis on day 18, as evidenced by decreases in testis weight, lumen formation, and spermatocyte nuclear volume per unit Sertoli cell and elevation of the germ cell apoptotic index. However, the two lowest doses of DES (0.1 and 0.01 microg) significantly increased spermatocyte nuclear volume per unit Sertoli cell. Similarly, treatment with either OP or Bis-A significantly advanced this and some of the other aspects of pubertal spermatogenesis. Maintenance of control animals on a soy-free diet also significantly advanced lumen formation and spermatocyte nuclear volume per unit Sertoli cell compared with controls fed a soy-containing diet. Administration of genistein reversed the stimulatory effects of a soy-free diet and significantly retarded most measures of pubertal spermatogenesis. In general, plasma FSH levels in the treatment groups changed in parallel to the spermatogenic changes (reduced when pubertal spermatogenesis retarded, increased when pubertal spermatogenesis advanced). By day 25, although the changes in FSH levels largely persisted, all of the stimulatory effects on spermatogenesis seen on day 18 in the various treatment groups were no longer evident. In adulthood, testis weight was decreased dose dependently in rats treated neonatally with DES, but only the lowest dose group (0.01 microg) showed evidence of mating (3 of 6) and normal fertility (3 litters). Animals treated neonatally with OP or Bis-A had normal or increased (Bis-A) testis weights and exhibited reasonably normal mating/fertility. Animals fed a soy-free diet had significantly larger testes than controls fed a soy-containing diet, and this difference was confirmed in a much larger study of more than 24 litters, which also showed a significant decrease in plasma FSH levels and a significant increase in body weight in the males kept on a soy-free diet. Neonatal treatment with genistein did not alter adult testis weight, and although most males exhibited normal mating and fertility, a minority did not mate or were infertile. It is concluded that 1) neonatal exposure of rats to low levels of estrogens can advance the first wave of spermatogenesis at puberty, although it is unclear whether this is due to direct effects of the estrogen or to associated elevation of FSH levels; 2) the effect of high doses of OP and Bis-A on these processes is essentially benign; and 3) the presence or absence of soy or genistein in the diet has significant short-term (pubertal spermatogenesis) and long-term (body weight, testis size, FSH levels, and possibly mating) effects on males.
Asunto(s)
Animales Recién Nacidos/fisiología , Estrógenos/farmacología , Fertilidad/efectos de los fármacos , Espermatogénesis/efectos de los fármacos , Testículo/anatomía & histología , Envejecimiento/fisiología , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Apoptosis/fisiología , Dieta , Exposición a Riesgos Ambientales , Hormona Folículo Estimulante/sangre , Inhibinas/sangre , Masculino , Tamaño de los Órganos , Ratas , Ratas Wistar , Túbulos Seminíferos/efectos de los fármacos , Células de Sertoli/citología , Glycine max , Testículo/citología , Testículo/efectos de los fármacos , Testículo/fisiologíaRESUMEN
Oestrogen exposure of the male during fetal/neonatal life can fundamentally alter the structure and function of the reproductive system, though how is unknown. This study examined whether such treatment was able to induce a 'female' characteristic, namely immunoexpression of progesterone receptor (PR), in the reproductive system of the male. Rats were treated on postnatal days 2, 4, 6, 8, 10 and 12 with either 10, 1 or 0.1 microg diethystilbestrol (DES) or with the vehicle (20 microl corn oil). Groups of control and treated rats were killed on days 18, 25, 35 and 90 (= adults) and tissues fixed in Bouins for immunolocalisation studies using antisera to PR (recognises A and B forms) and oestrogen receptor-beta (ER beta). PR immunoexpression was absent from all tissues studied in control rats at all ages with the exception of the parasympathetic ganglia of the prostate. In rats treated with 10 microg DES, intense immunoexpression of PR was detected in the nuclei of stromal, but not epithelial, cells of the caput and cauda epididymis, the vas deferens, seminal vesicles and at the base of the dorsolateral prostatic complex (DLPC) at day 18, but was absent from the ventral prostate and from the testis. DES induction of PR immunoexpression was evident after a single injection (on day 3) and at 18-35 days the intensity of immunoexpression was DES dose-dependent; rats treated neonatally with 0.1 microg DES showed no detectable PR immunoexpression at any age. These findings were confirmed by Western analysis which indicated that most of the PR induced was probably the B form. Co-localisation studies, using confocal microscopy, demonstrated that PR and ER beta frequently co-localised to the same stromal cells in the DLPC, epididymis and seminal vesicles of DES-treated rats at day 18, whereas epithelial cells, which also expressed ER beta, did not express PR. In the tissues studied, only occasional stromal cells expressed ER alpha in comparison to the more widespread expression of ER beta, although epithelial cell expression of ER alpha was also detected in the epididymis on day 18 (but not on day 10). In DES-treated rats, immunoexpression of PR in the reproductive tract decreased progressively in intensity from days 18-35 and was non-detectable in adulthood. In conclusion, these findings are interpreted as evidence that neonatal oestrogen treatment exerts pervasive 'reprogramming' effects throughout the reproductive system of the developing male as indicated by the induction of PR immunoexpression. This induction was restricted to stromal tissue even though both stromal and epithelial cells at most sites expressed ER beta and/or ER alpha.
Asunto(s)
Dietilestilbestrol/administración & dosificación , Estrógenos no Esteroides/administración & dosificación , Genitales Masculinos/fisiología , Receptores de Progesterona/biosíntesis , Envejecimiento/fisiología , Animales , Inmunohistoquímica , Masculino , Ratas , Células del Estroma/fisiologíaRESUMEN
BACKGROUND: Preexisting renal dysfunction has been reported to significantly increase the morbidity and mortality associated with orthotopic liver transplantation (OLT). OLT alone has been recommended for adults and children with end-stage liver disease and reversible causes of renal failure (i.e., hepatorenal syndrome), whereas combined liver and kidney transplantation (LKT) has been shown to be an effective treatment for adults with combined end-stage liver and kidney disease. The purpose of this study was to examine the role of LKT in children. METHODS: Between October of 1984 and 1997, 385 children less than 18 years of age underwent OLT at the University of Chicago. During this same time period 12 patients underwent LKT. Data were gathered by retrospective review of the patients medical records and by interviews conducted with the patients' families. RESULTS: Actuarial patient survival was comparable for children who underwent OLT alone and LKT (69% versus 67% at 5 years). All allograft losses in the LKT group were the result of patient death and occurred within the first 90 postoperative days. Factors associated with decreased patient survival included severity of illness as reflected by United Network of Organ Sharing status and LKT after failed OLT or cadaveric renal transplant. CONCLUSIONS: In children with concomitant endstage liver and kidney disease, LKT can be considered an effective therapeutic option in selected patients. Long-term patient survival in patients undergoing LKT is comparable to that of patients with normal renal function undergoing OLT alone.
Asunto(s)
Trasplante de Riñón , Trasplante de Hígado , Niño , Preescolar , Rechazo de Injerto , Humanos , Lactante , Trasplante de Riñón/mortalidad , Trasplante de Hígado/mortalidad , Trasplante HomólogoRESUMEN
The aim of this study was to evaluate in premenopausal women (10 sedentary obese women) the effects of 10 days of exercise on the suppression of whole body and regional lipolysis by insulin. Lipolysis was determined using 2H5-glycerol infusion and microdialysis of sc adipose tissue during a two-stage hyperinsulinemic-euglycemic clamp [10 (LO) and 20 (MO) mU/m x min]. Microdialysis probes were positioned in abdominal and femoral sc adipose tissue to monitor interstitial glycerol and blood flow. Basal plasma glycerol was 86.7 +/-17.0 and 100.3 +/- 19.8 micromol/L before and after training, respectively (P < 0.05). Plasma glycerol was suppressed to a greater extent after [to 47 +/- 5% (LO) and 42 +/- 5% (MO) of basal] than before [to 62 +/- 8% (LO) and 55 +/- 8% (MO) of basal] training. The rate of appearance of glycerol was suppressed to 49 +/- 7% and 40 +/- 5% of basal during LO and to 38 +/- 5% and 30 +/- 4% of basal during MO (P < 0.05) before and after training, respectively. There were no differences in the suppression of lipolysis in abdominal as well as femoral sc adipose tissue as evidenced by similar reductions in dialysate glycerol levels before and after training in each of these tissues. The results indicate that the antilipolytic response to insulin can be improved through endurance exercise training. Intraabdominal adipose tissue or skeletal muscle may be the site of improved antilipolytic response to insulin after training, as improvement was not evident in abdominal or femoral sc adipose tissue.