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1.
Aust Prescr ; 43(5): 152-159, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33093741

RESUMEN

The Australian Federal Government legalised access to medicinal cannabis in 2016 More than 100 different cannabis products are now available to prescribe. Most are oral preparations (oils) or capsules containing delta-9-tetrahydrocannabinol or cannabidiol. Dried-flower products are also available As most products are unregistered drugs, prescribing requires approval under the Therapeutic Goods Administration Special Access Scheme-B or Authorised Prescriber Scheme Special Access Scheme Category B applications can be made online, with approval usually being given within 24­48 hours. However, supply chain problems may delay dispensing by the pharmacy By the end of 2019, over 28,000 prescribing approvals had been issued to patients, involving more than 1400 doctors, mostly GPs. More than 70,000 approvals are projected by the end of 2020 Most prescriptions are for chronic non-cancer pain, anxiety, cancer-related symptoms, epilepsy and other neurological disorders. However, the evidence supporting some indications is limited Many doctors are cautious about prescribing cannabis. While serious adverse events are rare, there are legitimate concerns around driving, cognitive impairment and drug dependence with products containing delta-9-tetrahydrocannabinol. Cannabidiol-only products pose fewer risks

3.
Pediatr Endocrinol Rev ; 7(1): 22-31, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19696713

RESUMEN

The migration of the testes from the abdomen into the scrotum requires both an anatomical change in connecting structures and regulating signals to mediate this process. The gubernaculum is the principle structure in testicular descent. Its development appears to be controlled by insulin-like hormone 3 (INSL3) and androgen. This review article summarises the role of INSL3 and androgen in testicular descent. It also analyses the contribution of other hormones such as Mullerian inhibiting substance (MIS) and oestrogen to testicular descent. Furthermore, it reiterates findings that hormonal activation of the nervous system leads to neuropeptide secretion and further manipulation of this process.


Asunto(s)
Andrógenos/metabolismo , Insulina/metabolismo , Proteínas/metabolismo , Testículo/embriología , Testículo/metabolismo , Animales , Hormona Antimülleriana/metabolismo , Estrógenos/metabolismo , Humanos , Masculino
4.
J Pediatr Surg ; 46(8): 1539-43, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21843721

RESUMEN

AIM: During testicular descent (TD), the genitofemoral nerve (GFN) is masculinized by androgen. This study aimed to test whether androgen receptor (AR), estrogen receptor α (ERA), or estrogen receptor ß (ERB) are expressed during TD in the GFN spinal segments and dorsal root ganglia (DRG) in normal and flutamide-treated rats. METHODS: Time-mated Sprague-Dawley dams were injected with flutamide (75 mg/kg, subcutaneously (S/C) in sunflower oil) on embryonic (E) days 16 to 19. Embryonic and postnatal (P) male L1-2 spinal cord segments were collected (E16, E17, E19, P0, P2, and P4) in control and flutamide-treated groups (n = 5-10). Samples were fixed in 4% paraformaldehyde. Five-micrometer-thick sections were prepared immunohistochemically for AR, ERA, and ERB. RESULTS: During TD, ERB was expressed in L1-2 DRG. Surprisingly, AR was not expressed in prenatal DRG, only after P2. There was no ERA expression. Flutamide had no effect on AR, ERB, or ERA expression in the L1-2 DRG during TD. CONCLUSION: During the E window of androgen sensitivity, the GFN is not directly masculinized, with little AR expression and no change with flutamide over this period. Estrogen receptor ß is expressed in the DRG during TD. However, its relevance is yet to be determined.


Asunto(s)
Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , Receptores Androgénicos/metabolismo , Nervios Espinales/metabolismo , Testículo/embriología , Antagonistas de Andrógenos/farmacología , Animales , Flutamida/farmacología , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Inmunohistoquímica , Masculino , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Método Simple Ciego , Nervios Espinales/efectos de los fármacos
5.
J Pediatr Surg ; 46(12): 2358-62, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22152882

RESUMEN

BACKGROUND/PURPOSE: Inguinoscrotal testicular descent is controlled by androgens between embryonic days E16-19, but androgen receptor (AR) and estrogen receptor (ER) locations are unknown. We aimed to find AR, ERα, and ERß in the gubernaculum and inguinal fat pad (IFP) in normal rats and after flutamide treatment. METHODS: Sprague-Dawley timed-mated rats were injected with flutamide (75 mg/kg body weight/5% ethanol + oil) on E16-19 or vehicle alone. Male fetuses or pups (5-10/group) were collected at E16; E19; and postnatal (P) days 0, 2, 4, 8. Sections were prepared for hematoxylin and eosin or immunohistochemistry for AR, ERα, and ERß. Receptor labeling was quantitated as distinct nuclear labeling/100 µm(2) in gubernaculum and IFP. RESULTS: There was minimal gubernacular AR-labeling until E19, dramatically increasing postnatally. By contrast, at E16-E19 there was significant IFP AR immunoreactivity suppressed by flutamide (P < .05). No ERα expression was observed, but ERß was expressed in both gubernaculum and IFP, maximally at E16, but unchanged by flutamide. CONCLUSIONS: During the androgen sensitivity window (E16-19), the gubernaculum contains ERß but minimal ERα or AR, while the IFP, which is supplied by the genitofemoral nerve, contains abundant AR that are flutamide-sensitive. These results suggest that the IFP could be the site of androgenic action controlling gubernacular development.


Asunto(s)
Antagonistas de Andrógenos/farmacología , Receptor alfa de Estrógeno/efectos de los fármacos , Receptor beta de Estrógeno/efectos de los fármacos , Flutamida/farmacología , Grasa Intraabdominal/efectos de los fármacos , Ligamentos/efectos de los fármacos , Receptores Androgénicos/efectos de los fármacos , Testículo/embriología , Animales , Núcleo Celular/química , Criptorquidismo/fisiopatología , Receptor alfa de Estrógeno/biosíntesis , Receptor alfa de Estrógeno/genética , Receptor beta de Estrógeno/biosíntesis , Receptor beta de Estrógeno/genética , Femenino , Nervio Femoral/fisiología , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Edad Gestacional , Grasa Intraabdominal/embriología , Grasa Intraabdominal/crecimiento & desarrollo , Grasa Intraabdominal/inervación , Grasa Intraabdominal/metabolismo , Ligamentos/embriología , Ligamentos/crecimiento & desarrollo , Ligamentos/metabolismo , Masculino , Glándulas Mamarias Animales/embriología , Glándulas Mamarias Animales/crecimiento & desarrollo , Glándulas Mamarias Animales/metabolismo , Embarazo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Receptores Androgénicos/biosíntesis , Receptores Androgénicos/genética , Escroto/embriología , Escroto/crecimiento & desarrollo , Testículo/crecimiento & desarrollo , Testosterona/fisiología
6.
Semin Pediatr Surg ; 19(3): 215-24, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20610195

RESUMEN

Cryptorchidism is a very common anomaly of the male genitalia, affecting 2%-4% of male infants and is more common in premature infants. There are two separate stages of testicular descent. The first stage occurs at 8-15 weeks' gestation in the human fetus and is characterized by enlargement of the genito-inguinal ligament, or gubernaculum, and regression of the cranial suspensory ligament. The testis remains close to the future inguinal region as the fetal abdomen grows. Leydig cells in the testis produce insulin-like hormone 3, which stimulates the caudal gubernaculum to grow and become thicker. Mullerian inhibiting substance may have a role in the first phase of descent by stimulating the swelling reaction in the gubernaculum. The second phase of testicular descent requires migration of the gubernaculum and testis from the inguinal region to the scrotum, between 25 and 35 weeks' gestation. The genitofemoral nerve releases calcitonin gene-related peptide, a neurotransmitter that provides a chemotactic gradient to guide migration. The exact cause of cyrptorchidism remains elusive. Information is mainly derived from animal studies (especially in rodents), which may not extrapolate to the human setting. These findings, however, do have some similarities among mammalian species. The current recommended timing for orchidopexy is between 6 and 12 months of life in an effort to preserve the spermatogonia--the stem cells for subsequent spermatogenesis. Despite surgical treatment by orchidopexy, the long-term outcome still remains problematic and controversial. Impaired fertility (33% in unilateral cases and 66% in bilateral undescended testes) and a cancer risk 5-10 times greater than normal is observed over time. Further research into the cause and management of undescended testes is necessary.


Asunto(s)
Criptorquidismo/embriología , Criptorquidismo/cirugía , Testículo/embriología , Criptorquidismo/epidemiología , Estudios de Seguimiento , Humanos , Incidencia , Recién Nacido , Masculino , Orquidopexia/métodos , Medición de Riesgo , Neoplasias Testiculares/prevención & control , Testículo/anomalías , Resultado del Tratamiento
7.
J Pediatr Surg ; 45(10): 2074-86, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20920735

RESUMEN

It has been hypothesized that poor semen quality, testis cancer, undescended testis, and hypospadias are symptoms of one underlying entity--the testicular dysgenesis syndrome--leading to increasing male fertility impairment. Though testicular cancer has increased in many Western countries during the past 40 years, hypospadias rates have not changed with certainty over the same period. Also, recent studies demonstrate that sperm output may have declined in certain areas of Europe but is probably not declining across the globe as indicated by American studies. However, at the same time, there is increasing recognition of male infertility related to obesity and smoking. There is no certain evidence that the rates of undescended testes have been increasing with time during the last 50 years. In more than 95% of the cases, hypospadias is not associated with cryptorchidism, suggesting major differences in pathogenesis. Placental abnormality may occasionally cause both cryptorchidism and hypospadias, as it is also the case in many other congenital malformations. The findings of early orchidopexy lowering the risk of both infertility and testicular cancer suggest that the abnormal location exposes the cryptorchid testis to infertility and malignant transformation, rather than there being a primary abnormality. Statistically, 5% of testicular cancers only are caused by cryptorchidism. These data point to the complexity of pathogenic and epidemiologic features of each component and the difficulties in ascribing them to a single unifying process, such as testicular dysgenesis syndrome, particularly when so little is known of the actual mechanisms of disease.


Asunto(s)
Criptorquidismo/etiología , Disgenesia Gonadal/complicaciones , Hipospadias/etiología , Criptorquidismo/epidemiología , Criptorquidismo/genética , Estudios de Seguimiento , Disgenesia Gonadal/epidemiología , Disgenesia Gonadal/etiología , Humanos , Hipospadias/epidemiología , Hipospadias/genética , Lactante , Recién Nacido , Masculino , Modelos Biológicos , Neoplasias Testiculares/etiología
8.
J Pediatr Surg ; 45(2): 414-8; discussion 418, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20152364

RESUMEN

BACKGROUND/PURPOSE: Inguinoscrotal testicular descent is controlled by androgens and the genitofemoral nerve, but the trigger for what makes the gubernaculum become a migratory organ like a limb bud remains unknown. Recent observations in the flutamide-treated rat suggested a link with the mammary line. We aimed, therefore, to reassess histologic anatomy in 2 different rodent models of androgen blockade, the testicular feminisation mouse (TFM) and the flutamide-treated rat. METHODS: Neonatal TFM mice and fetal and neonatal rats after pretreatment of dams with an antiandrogen, flutamide (75 mg/kg; sunflower oil; days 16-19), were prepared for histologic analysis of the inguinal region and compared with fetal and neonatal controls. RESULTS: Fetal control rats (E15.5 days) showed a mammary bud just outside the future inguinal canal adjacent to the gubernaculum. Neonatal TFM mice showed persistence of the inguinal breast bud supplied by the genitofemoral nerve. Flutamide-treated rats (D2) showed the gubernaculum surrounded by a persisting breast bud. CONCLUSIONS: The inguinal mammary line is adjacent to the gubernaculum in fetal rodents, and after androgen blockade, the gubernaculum becomes connected to the breast. The male mammary line, which is hidden in plain sight outside the inguinal canal, is made visible by androgen blockade. It may be the missing link in testicular descent, regulating gubernacular migration.


Asunto(s)
Antagonistas de Andrógenos/farmacología , Andrógenos/fisiología , Desarrollo Embrionario/fisiología , Conducto Inguinal/embriología , Glándulas Mamarias Humanas/embriología , Escroto/embriología , Testículo/embriología , Pared Abdominal/embriología , Síndrome de Resistencia Androgénica/inducido químicamente , Animales , Animales Recién Nacidos , Desarrollo Embrionario/efectos de los fármacos , Femenino , Madurez de los Órganos Fetales/efectos de los fármacos , Madurez de los Órganos Fetales/fisiología , Feto/efectos de los fármacos , Feto/fisiología , Flutamida/farmacología , Humanos , Masculino , Ratones , Modelos Animales , Embarazo , Ratas , Testículo/fisiología
9.
J Pediatr Surg ; 44(12): 2330-4, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20006020

RESUMEN

AIM: Inadequate androgen activity is a likely cause of cryptorchidism in humans, affecting inguinoscrotal testicular descent. Flutamide, a nonsteroidal antiandrogen, produces cryptorchidism in rats. We aimed to determine the anatomical and histologic effects of flutamide. METHODS: Time-mated Sprague-Dawley female rats were injected subcutaneously with flutamide (75 mg/kg in sunflower oil) on days 16 to 19 of pregnancy. Embryonic (E) and postnatal (P) male offspring were collected (E16, E19, P0, P2, P4, P8) in control and flutamide-treated groups (n = 5-10). Samples were fixed in 4% paraformaldehyde. Five-micrometer-thick sections were prepared for hematoxylin and eosin, trichrome and immunohistochemical stains (Desmin, TuJ1, Ki67). This identified muscle and neural cells and areas of cell proliferation. RESULTS: Postnatally, the gubernaculum in flutamide-treated rats had more mesenchyme and muscle than controls. Gubernacular eversion failed, and mammary tissue persisted around the gubernaculum in flutamide-treated rats. Flutamide had no effect on embryonic gubernacular anatomy and histology. CONCLUSIONS: Prenatal androgens altered postnatal gubernacular anatomy and histology in the postnatal period. Our findings indicate that the failure of gubernacular differentiation and migration may be because of the ongoing presence of mammary tissue in the region of the external inguinal ring.


Asunto(s)
Antagonistas de Andrógenos/farmacología , Criptorquidismo/inducido químicamente , Flutamida/farmacología , Glándulas Mamarias Humanas/embriología , Animales , Animales Recién Nacidos , División Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Desarrollo Embrionario , Femenino , Humanos , Conducto Inguinal/embriología , Conducto Inguinal/crecimiento & desarrollo , Masculino , Glándulas Mamarias Humanas/anomalías , Glándulas Mamarias Humanas/efectos de los fármacos , Embarazo , Ratas , Ratas Sprague-Dawley , Escroto/efectos de los fármacos , Escroto/crecimiento & desarrollo , Testículo/efectos de los fármacos , Testículo/embriología , Testículo/fisiología
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