Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
1.
J Endocrinol Invest ; 47(7): 1733-1741, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38244140

RESUMEN

OBJECTIVE: Pasireotide LAR (PAS-LAR) was released in Italy in 2017 to treat acromegaly patients resistant to SRLs (Somatostatin Receptors Ligands). The long-term follow-up data of PAS-LAR therapy in Italy are limited. This study aimed to evaluate the efficacy and safety of PAS-LAR in acromegaly. DESIGN: Patients with acromegaly in PAS-LAR treatment were enrolled in three tertiary Italian endocrinological centers and evaluated by a retrospective observational real-life multicentre study. METHODS: Patients have been studied before (baseline) and 1, 6, 12, 24 and > 36 months after PAS-LAR start. Clinical, biochemical, and pituitary magnetic resonance data were collected, along with information on adverse events. Acromegaly disease activity was classified according to the IGF-1 index (normal value < 1.0). RESULTS: Fifty patients (female 23) were enrolled. PAS-LAR treatment (mean follow-up 24 ± 16 months) significantly decreased IGF-1 levels (IGF-1 index baseline vs last visit: 1.9 ± 0.6 vs 1.2 ± 0.6, p < 0.0001). At the last visit, 67% of patients had controlled disease, and 44% showed a decrease in tumor volume. Clinical and biochemical efficacy was observed as early as after 1-month of PAS-LAR treatment (IGF-1 index baseline vs 1-month: 1.9 ± 0.6 vs 1.4 ± 0.7, p < 0.0001). Also, 50% of patients referred headache improvement or disappearance. Fifteen patients discontinued PAS-LAR due to failure of treatment and poor glycaemic control. The prevalence of diabetes increased from 33% at the baseline to 54% at the last visit (p = 0.0072). CONCLUSION: In real-life settings, PAS-LAR significantly decreases symptoms, IGF-1 levels, and the size of adenoma in patients with acromegaly resistant to SRLs. Beneficial effects may occur early after the first injection.


Asunto(s)
Acromegalia , Somatostatina , Humanos , Femenino , Acromegalia/tratamiento farmacológico , Masculino , Somatostatina/análogos & derivados , Somatostatina/uso terapéutico , Somatostatina/administración & dosificación , Persona de Mediana Edad , Estudios de Seguimiento , Estudios Retrospectivos , Adulto , Resultado del Tratamiento , Factor I del Crecimiento Similar a la Insulina/análisis , Factor I del Crecimiento Similar a la Insulina/metabolismo , Italia/epidemiología , Adenoma Hipofisario Secretor de Hormona del Crecimiento/tratamiento farmacológico , Adenoma Hipofisario Secretor de Hormona del Crecimiento/complicaciones , Anciano , Hormona de Crecimiento Humana/sangre
2.
Biol Open ; 6(7): 956-966, 2017 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-28522431

RESUMEN

Ionocytes of euryhaline teleost fish secrete NaCl, under regulation by serine and threonine kinases, including with-no-lysine kinase (WNK1) and p38 mitogen-activated protein kinase (MAPK). Mummichogs (Fundulus heteroclitus L.) were acclimated to freshwater (FW), full strength seawater (SW) and hypersaline conditions (2SW). Immunocytochemistry of ionocytes in opercular epithelia of fish acclimated to SW and 2SW revealed that WNK1-anti-pT58 phosphoantibody localized strongly to accessory cells and was present in the cytosol of ionocytes, close to cystic fibrosis transmembrane conductance regulator (CFTR) in the apical membrane and the sodium potassium 2 chloride cotransporter (NKCC) in the basolateral membrane. In FW acclimated fish, WNK1 localized to a sub-apical zone, did not colocalize with apical membrane-located sodium chloride cotransporter (NCC), and typically was present in one cell of paired ionocytes and in some single ionocytes. Forskolin treatment (10 µM, 30 min) increased WNK1 immunofluorescence in SW ionocytes only, while hypertonicity had little effect, compared to controls. Anti-p38-MAPK antibody localized to the cytosolic compartment. The distribution of WNK1 and p38MAPK is consistent with a proximal position in regulatory cascades, rather than directly affecting transporters. The strong staining of accessory cells by WNK1 phosphoantibody infers an osmoregulatory function for WNK.

3.
J Endocrinol Invest ; 32(3): 202-9, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19542735

RESUMEN

OBJECTIVE: To evaluate efficacy and safety of lanreotide autogel (ATG) 120 mg injections every 4-8 weeks in somatostatin analogue-naïve patients with acromegaly. DESIGN: Open, non-comparative, phase III, multicenter clinical study. METHODS: Fifty-one patients (28 women, aged 19-78 yr): 39 newly diagnosed (de novo) and 12 who had previously undergone unsuccessful surgery (post-op, 11 macro and 1 micro) were studied. ATG 120 mg was initially given every 8 weeks for 24 weeks and subsequently changed according to GH levels: if 5 microg/l every 4 weeks (group C, 19 patients). Treatment duration was 48-52 weeks. The primary objective was to control GH and IGF-I levels (GH

Asunto(s)
Acromegalia/tratamiento farmacológico , Péptidos Cíclicos/administración & dosificación , Somatostatina/análogos & derivados , Acromegalia/etiología , Adenoma/tratamiento farmacológico , Adulto , Anciano , Algoritmos , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/efectos adversos , Femenino , Geles/administración & dosificación , Geles/efectos adversos , Adenoma Hipofisario Secretor de Hormona del Crecimiento/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Péptidos Cíclicos/efectos adversos , Somatostatina/administración & dosificación , Somatostatina/efectos adversos , Resultado del Tratamiento , Adulto Joven
4.
J Endocrinol Invest ; 32(5): 460-4, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19494715

RESUMEN

BACKGROUND: Peri-operative steroids are administered routinely to patients with pituitary adenoma undergoing transsphenoidal adenomectomy (TSA). AIM: To evaluate hypothalamic-pituitary-adrenal (HPA) axis before and after programmed endoscopic TSA (E-TSA) in patients with clinically non-functioning pituitary macroadenoma (NFPA). DESIGN: Open prospective. SETTING: Tertiary referral hospitals. PATIENTS: Seventy-two consecutive patients (20-87 yr, 37 males). INTERVENTIONS: Adrenal steroid replacement therapy (ASRT) was given only in patients with hypocortisolism [08:00 h cortisol (F) <8 microg/dl]. MAIN OUTCOME MEASUREMENTS: After ETSA, achieving wide (>90%) selective resection of the adenoma in all, F and clinical picture were checked at day 2. The low-dose (1 microg) ACTH test (LDACTH) was performed at 6 weeks and repeated at 12 months. RESULTS: Hypocortisolism was present pre-operatively in 14 patients (19.4%), persisted post-operatively in all but one, and was detected de novo at the post-operative day 2 control in 6 (10.3%). In all but one the post-operative day 2 basal F and peak F during LDACTH test were concordant. No patient whose F was > 8 microg/dl was treated with ASRT or developed symptoms of adrenal failure during the follow-up (1-11 yr, median 5). CONCLUSIONS: HPA function is usually preserved in NFPA and is infrequently impaired after complete tumor removal by E-TSA. The 08:00 h. plasma cortisol evaluation before and 2 days after surgery, using as cut-off the value of 8 microg/dl, allows full evaluation of HPA status. Peri-operative steroid treatment should be given only in patients with hypocortisolism.


Asunto(s)
Adenoma/diagnóstico , Hidrocortisona/sangre , Sistema Hipotálamo-Hipofisario/fisiopatología , Neoplasias Hipofisarias/diagnóstico , Sistema Hipófiso-Suprarrenal/fisiopatología , Adenoma/sangre , Adenoma/fisiopatología , Adenoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Hipofisarias/sangre , Neoplasias Hipofisarias/fisiopatología , Neoplasias Hipofisarias/cirugía , Complicaciones Posoperatorias/diagnóstico , Periodo Posoperatorio , Periodo Preoperatorio , Pronóstico , Adulto Joven
5.
J Endocrinol Invest ; 31(8): 704-10, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18852531

RESUMEN

CONTEXT: Development of gallstones (GS) is reported during the use of somatostatin analogs (SA) that are at present the mainstay for the medical treatment of acromegaly. OBJECTIVE: To review the prevalence and clinical and biochemical correlates of GS in acromegalic patients. DESIGN AND SETTING: Retrospective survey on hospital records in acromegalic patients followed up in the last 20 yr in tertiary referral centers. PATIENTS: Four hundred and fifty-nine patients (272 females). MAIN OUTCOME MEASURES: According to SA use and GS occurrence, patients were divided in 4 groups: 1) treated with SA without GS (SA+GS-), 2) GS developed while on SA (SA+GS+), 3) GS without SA use (SA-GS+), 4) neither GS nor SA (SA-GS-). RESULTS: Patients were unevenly distributed in the 4 groups: 232, 125, 38, 64, respectively, pointing to a prevalence of GS in acromegaly of 8.3% at diagnosis with an additional 35% developing GS during SA. GS occurred after 3 months-18 yr (median 3 yr) of SA treatment, were diagnosed after symptoms in 17.6%, were associated to steatosis, ultrasound biliary dilation, and biochemical cholestasis, in 25.6%, 12.8%, and 4% of patients, respectively. Ursodehoxicolic acid was administered after GS occurrence, causing their dissolution in 39% of patients after 3-48 months (median 12). Cholecystectomy was performed in 16.8%of patients in group 2. At multivariate analysis obesity, dyslipidemia, and SA treatment were independent predictors of GS onset, whereas gender and age were not. CONCLUSIONS: GS are a frequent occurrence in acromegalic patients treated with SA, may occur at any time, but are seldom symptomatic or prompt acute surgery. Obesity and dyslipidemia appear to play a major role in the occurrence of GS in acromegalic patients on SA treatment.


Asunto(s)
Acromegalia/tratamiento farmacológico , Cálculos Biliares/inducido químicamente , Somatostatina/análogos & derivados , Somatostatina/uso terapéutico , Acromegalia/complicaciones , Adulto , Estudios de Cohortes , Dislipidemias/complicaciones , Dislipidemias/epidemiología , Femenino , Estudios de Seguimiento , Cálculos Biliares/epidemiología , Hormona de Crecimiento Humana/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/epidemiología , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Somatostatina/efectos adversos
7.
Environ Mol Mutagen ; 46(3): 182-8, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16206220

RESUMEN

The genotoxic effects associated with automobile painting were analyzed using a panel of biomarkers. Chromosomal aberrations (CAs), sister chromatid exchange (SCE), and micronuclei were evaluated in 25 car painters (12 smokers, 13 nonsmokers) working in different automobile paint-shops in Italy and in 37 control subjects. The controls were healthy blood donors (14 smokers, 23 non-smokers) that were matched with the experimental population for gender and age. Air samples were analyzed regularly at the work places, and elevated concentrations of benzene and toluene were detected consistently. The exposed group had higher frequencies of CAs (both chromosome- and chromatid-type), micronuclei, and SCE (P < 0.5 - P < 0.001). Furthermore, exposed and control subjects were also genotyped for GSTM1 and GSTT1 polymorphism. No significant associations were detected between the biomarker responses and either the GSTM1 or GSTT1 genotype of the subjects, but the small sample size does not allow definite conclusions on the relationship between the genetic polymorphism and the biomarkers. The results indicate that automobile painters have increased levels of clastogenic and possible aneugenic damage and that smoking may be a confounding factor for the responses.


Asunto(s)
Biomarcadores , Aberraciones Cromosómicas , Cromosomas/efectos de los fármacos , Daño del ADN , Adulto , Automóviles , Benceno/química , Estudios de Casos y Controles , ADN/efectos de los fármacos , Genotipo , Glutatión Transferasa/genética , Homocigoto , Humanos , Industrias , Italia , Linfocitos/citología , Linfocitos/efectos de los fármacos , Masculino , Pruebas de Micronúcleos , Persona de Mediana Edad , Mutágenos/química , Exposición Profesional , Polimorfismo Genético , Intercambio de Cromátides Hermanas , Fumar , Tolueno/química
8.
J Exp Zool A Comp Exp Biol ; 303(2): 132-42, 2005 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-15662660

RESUMEN

To examine the role of cortisol in seawater osmoregulation in a euryhaline teleost, adult killifish were acclimated to brackish water (10 per thousand) and RU486 or vehicle was administered orally in peanut oil daily for five days at low (40 mg.kg(-1)) or high dose (200 mg.kg(-1)). Fish were transferred to 1.5 x seawater (45 per thousand) or to brackish water (control) and sampled at 24 h and 48 h after transfer, when Cl- secretion is upregulated. At 24 h, opercular membrane Cl- secretion rate, as Isc, was increased only in the high dose RU486 group. Stimulation of membranes by 3-isobutyl-1-methylxanthine and cAMP increased Isc in vehicle treated controls but those from RU486-treated animals were unchanged and membranes from brackish water animals showed a decrease in Isc. At 48 h, Isc increased and transepithelial resistance decreased in vehicle and RU486 groups, compared to brackish water controls. Plasma cortisol increased in all groups transferred to high salinity, compared to brackish water controls. RU486 treated animals had higher cortisol levels compared to vehicle controls. Vehicle treated controls had lower cortisol levels than untreated or RU486 treated animals, higher stimulation of Isc, and lower hematocrit at 24 h, beneficial effects attributed to increased caloric intake from the peanut oil vehicle. Chloride cell density was significantly increased in the high dose RU486 group at 48 hours, yet Isc was unchanged, suggesting a decrease in Cl- secretion per cell. Thus cortisol enhances NaCl secretion capacity in chloride cells, likely via glucocorticoid type receptors.


Asunto(s)
Fundulidae/fisiología , Receptores de Glucocorticoides/fisiología , Agua de Mar , Adaptación Fisiológica , Animales , Regulador de Conductancia de Transmembrana de Fibrosis Quística/fisiología , Relación Dosis-Respuesta a Droga , Fundulidae/metabolismo , Branquias/enzimología , Transporte Iónico/fisiología , Mifepristona/farmacología , Músculo Esquelético/metabolismo , Receptores de Glucocorticoides/antagonistas & inhibidores , Cloruro de Sodio , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Equilibrio Hidroelectrolítico/efectos de los fármacos , Equilibrio Hidroelectrolítico/fisiología
9.
Metabolism ; 53(5): 563-70, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15131758

RESUMEN

Sex steroids play an important role in modulating pulsatile growth hormone (GH) release, acting at both hypothalamic and pituitary level in both humans and experimental animals. Selective estrogen receptor modulators (SERMs) act as either estrogen receptor agonists or antagonists in a tissue-selective manner. In postmenopausal women, serum GH levels correlate positively with endogenous estradiol levels and insulin-like grwoth factor-I (IGF-I) is positively related to bone mineral density (BMD) at the spine and hip. The aim of the present study was to evaluate, for the first time, the direct effect of LY117018, an analog of raloxifene, on GH secretion from both human and rodent pituitary cells in vitro. Our results demonstrated that pharmacological concentrations of the raloxifene analog LY117018 can stimulate GH secretion through a direct action on the pituitary. LY117018 also showed an estrogen-like activity, inducing the proliferation of rat pituitary GH-secreting adenomatous cells (GH1).


Asunto(s)
Hormona del Crecimiento/metabolismo , Pirrolidinas/farmacología , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Tiofenos/farmacología , Adenoma/metabolismo , Adulto , Anciano , Animales , División Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Estradiol/farmacología , Femenino , Hormona Liberadora de Hormona del Crecimiento/farmacología , Humanos , Masculino , Persona de Mediana Edad , Hipófisis/citología , Pirrolidinas/química , Clorhidrato de Raloxifeno/química , Ratas , Ratas Sprague-Dawley , Tasa de Secreción/efectos de los fármacos , Tamoxifeno/farmacología , Tiofenos/química
10.
J Endocrinol Invest ; 26(4): 347-52, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12841543

RESUMEN

In some acromegalic patients medical treatment does not succeed in normalizing GH/IGF-I values. Data showing IGF-I suppression in acromegaly by estrogen and by tamoxifen use prompted us to reevaluate the effects of estroprogestins (EP) supplementation on GH/IGF-I levels in acromegalic women resistant or only partially sensitive to medical treatment. Eight active acromegalic women (30-52 yr, 4 with regular menses) entered a prospective open pilot study. Three of them, resistant to medical treatment, were off therapy; the remaining five, partially sensitive, maintained it at the maximally effective dosages throughout the study. Patients were treated with a triphasic pill (ethynil-estradiol 30-40-30 microg/day and desogestrel 50-70-100 mg/day) for 13 +/- 7 months. IGF-I levels fell from 512 (median, interquartile 436-657) microg/l to 282 (244-526) microg/l (p=0.0414); the decrease was observed in 6 patients (75%), and normal values were reached in 4 (50%). GH levels did not change [basal 7.6 (6.2-8.6) microg/l, final 7.6 (6.5-8.3) microg/l]. Effectiveness of treatment was not dependent on concomitant anti-GH treatment or gonadal status. In all patients IGF-I levels re-increased after EP withdrawal. This pilot study shows a marked IGF-I lowering effect of pill in acromegalic women, and warrants a prospective randomized study in patients resistant or partially sensitive to other medical treatments.


Asunto(s)
Acromegalia/sangre , Acromegalia/tratamiento farmacológico , Anticonceptivos Sintéticos Orales/farmacología , Desogestrel/farmacología , Etinilestradiol/farmacología , Factor I del Crecimiento Similar a la Insulina/efectos de los fármacos , Adulto , Anticonceptivos Sintéticos Orales/uso terapéutico , Desogestrel/uso terapéutico , Estrógenos/farmacología , Estrógenos/uso terapéutico , Etinilestradiol/uso terapéutico , Femenino , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Persona de Mediana Edad , Proyectos Piloto , Progestinas/farmacología , Progestinas/uso terapéutico , Estudios Prospectivos
11.
J Exp Biol ; 205(Pt 9): 1265-73, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11948203

RESUMEN

Cellular distribution of cystic fibrosis transmembrane conductance regulator (CFTR) immunofluorescence was detected by monoclonal antibody directed to the C terminus of killifish CFTR (kfCFTR) in chloride cells of fresh water (FW) adapted fish and animals transferred to sea water (SW) for 24h, 48h and 14+ days. Confocal microscopy allowed localization within mitochondria-rich (MR) cells to be determined as superficial (i.e. in the apical membrane) or deeper within the cytoplasm of the cells. In FW, 90 % of MR cells had diffuse kfCFTR immunofluorescence in the central part of the cytosol, with only 8.1 % having apical kfCFTR, which was 6.6+/-0.54 microm below the microridges of surrounding pavement cells. Curiously, FW but not SW pavement cells also had positive immunofluorescence to kfCFTR. After 24h in SW, a time when kfCFTR expression is elevated, a condensed punctate immunofluorescence appeared among 18.8 % of MR cells, 13.4+/-0.66 microm (mean +/- S.E.M.) below the surface of the cells. By 48h, a majority (76.3 %) of MR cells had punctate kfCFTR distribution and the distance from the surface was less (7.8+/-0.2 microm), a distribution approaching the SW-acclimated condition (i.e. all MR cells showing kfCFTR immunofluorescence, 6.1+/-0.04 microm below the surface). In contrast, NKCC immunofluorescence was condensed and localized in lateral parts of MR cell complexes in FW animals and then redistributed to the whole basal cytoplasm after acclimation to SW. CFTR, the anion channel responsible for Cl(-) secretion in marine teleosts, redistributes in MR cells during SW acclimation by condensation of a diffuse distribution below the apical crypt, followed by translocation and insertion in the apical membrane. NKCC, the cotransporter that translocates Cl(-) across the basolateral membrane, moves from an eccentric cytosolic location in FW to a diffuse basolateral localization in SW chloride cells.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Fundulidae/metabolismo , Simportadores de Cloruro de Sodio-Potasio/metabolismo , Adaptación Fisiológica , Animales , Cloruros/metabolismo , Fundulidae/anatomía & histología , Inmunohistoquímica , Mitocondrias/metabolismo , Agua de Mar , Fracciones Subcelulares/metabolismo
12.
J Exp Biol ; 205(Pt 6): 745-58, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11914383

RESUMEN

Sections of posterior intestine of the euryhaline killifish Fundulus heteroclitus adapted to sea water were stimulated by the calcium ionophore ionomycin (1 micromol l(-1)) in combination with agents to elevate intracellular cyclic AMP levels, 0.5 mmol l(-1) dibutyryl-cyclic AMP (db-cAMP) with 0.1 mmol l(-1) 3-isobutyl-1-methylxanthine (IBMX). Intestinal bag preparations from recently fed animals (but not from overnight unfed animals) changed from fluid absorption (+18.9+/-8.30 microl cm(-2) h(-1), N=8) in the untreated control period to net fluid secretion after stimulation (-7.43+/-1.30 microl cm(-2) h(-1), N=8, P<0.01; means +/- S.E.M.), indicative of the capacity of teleost intestine to undergo secretion. Posterior intestinal pieces mounted in vitro in Ussing-style membrane chambers showed net Cl(-) uptake (+2.245+/-0.633 microequiv cm(-2) h(-1), N=7) that turned to net secretion following stimulation by ionomycin + db-cAMP + IBMX (-3.809+/-1.22 microequiv cm(-2) h(-1), N=7, P<0.01). Mucosal application of the anion channel blocker 1 mmol l(-1) diphenylamine-2-carboxylate (DPC) after ionomycin + db-cAMP + IBMX treatment significantly reduced serosal-to-mucosal unidirectional Cl(-) flux (P<0.001), net Cl(-) flux (P<0.05), short-circuit current (I(sc), P<0.001) and tissue conductance (G(t), P<0.001), while 0.1 mmol l(-1) 4,4'-diisothiocyano-2,2'-stilbene-disulphonic acid (DIDS, a blocker of anion exchange) was without effect. Stimulation by db-cAMP + IBMX (no ionomycin) significantly increased unidirectional fluxes, I(sc) and G(t) but did not produce net Cl(-) secretion. Ionomycin alone produced a transient increase in I(sc) but had no effect on G(t) and caused no significant changes in unidirectional or net Cl(-) fluxes. Addition of db-cAMP + IBMX after ionomycin treatment produced net secretion of Cl(-) and large increases in unidirectional fluxes and G(t). Cystic fibrosis transmembrane conductance regulator (CFTR) was immunocytochemically localized with a monoclonal mouse antibody to the carboxy terminus and found to be present in the cytoplasm and basolateral membranes of all enterocytes and in the brush-border membrane of some cells, whereas NKCC immunofluorescence, demonstrating the presence of the Na(+)/K(+)/2Cl(-) cotransporter, was present in the cytoplasm and brush-border membrane. We conclude that the teleost intestine is capable of salt and fluid secretion only if intracellular Ca(2+) and cyclic AMP pathways are stimulated together and that this secretion appears to involve activation of CFTR ion channels in the apical membrane of a subpopulation of enterocytes.


Asunto(s)
Líquidos Corporales/metabolismo , Regulador de Conductancia de Transmembrana de Fibrosis Quística/fisiología , Fundulidae/fisiología , Intestinos/fisiología , Cloruro de Sodio/metabolismo , 1-Metil-3-Isobutilxantina/farmacología , Animales , Bucladesina/farmacología , Calcio , Bloqueadores de los Canales de Calcio/farmacología , Cloruros/metabolismo , AMP Cíclico/metabolismo , Regulador de Conductancia de Transmembrana de Fibrosis Quística/análisis , Conductividad Eléctrica , Femenino , Técnica del Anticuerpo Fluorescente , Inmunohistoquímica , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Intestinos/efectos de los fármacos , Ionomicina/farmacología , Masculino , Simportadores de Cloruro de Sodio-Potasio/análisis , ortoaminobenzoatos/farmacología
13.
Eur J Endocrinol ; 145(6): 717-26, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11720896

RESUMEN

BACKGROUND: Recent data has raised skepticism regarding the long-term effectiveness of radiotherapy (RxT) in acromegaly and its role as an ancillary tool to neurosurgery (Tx). PATIENTS: We evaluated 72 acromegalic patients previously submitted to RxT. Data were discarded in 23 patients, who were lost to follow-up, operated on after RxT or irradiated with techniques different from external conventional fractionated RxT. Among the remaining 49 (five with mixed GH-prolactin adenoma), 34 were irradiated after surgical failure and 15 as primary treatment. A second cycle of RxT was administered in two. RESULTS: (i) GH/IGF-I. After a median follow-up of 14 years (range 3-41), normal age-matched IGF-I levels were reached in eight patients (16%) after 10 years, and GH levels <2.5 microg/l in six (12%) after 9 years. The rate of persistently pathological hormonal levels was still 90% at 25 years. All patients with GH/IGF-I normalization had undergone irradiation without any antisecretory drug. Neither basal GH nor tumor size affected the outcome of RxT. In three patients (6%) a relapse/worsening occurred. (ii) Tumor size. Tumor shrank after 8.5 years in 24 patients (49%), in nine of whom during GH-suppressive treatment. Tumor shrinkage was not predictive of hormonal normalization. (iii) Side-effects. Hypopituitarism was diagnosed in four patients (selective in three and global in one) and GH deficiency in one. Three patients had neurological side-effects and meningioma was shown in two patients. CONCLUSION: RxT is unable to cure acromegaly, because it seldom achieves hormonal normalization even after a very prolonged follow-up. Concomitant antisecretory treatment seems to counteract its effects. RxT can still play a role in those patients with large tumor remnants, because of its capacity to shrink tumor size.


Asunto(s)
Acromegalia/radioterapia , Insuficiencia del Tratamiento , Adenoma/patología , Adenoma/radioterapia , Adolescente , Adulto , Anciano , Fraccionamiento de la Dosis de Radiación , Femenino , Hormona de Crecimiento Humana/análisis , Hormona de Crecimiento Humana/sangre , Hormona de Crecimiento Humana/metabolismo , Humanos , Factor I del Crecimiento Similar a la Insulina/análisis , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/patología , Neoplasias Hipofisarias/radioterapia , Prolactinoma/patología , Prolactinoma/radioterapia , Radioterapia/efectos adversos , Estudios Retrospectivos
14.
J Exp Biol ; 204(Pt 11): 1889-99, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11441031

RESUMEN

Freshwater-adapted killifish (Fundulus heteroclitus) opercular epithelia were dissected and subjected to blood-side hypertonic bathing solution in Ussing-style chambers to simulate the increase in blood osmolality during migration to sea water. Conversely, seawater-acclimated killifish opercular epithelia were subjected to hypotonic bathing solutions to simulate the initial stages of migration to fresh water. Freshwater-acclimation (hypertonic stress) induced a rapid (approximately 30 min) increase in membrane conductance (G(t)) from 3.10+/-0.56 to 7.52+/-1.15 mS x cm(-2) (P<0.01, N=27), whereas seawater-acclimation (hypotonic stress) induced a rapid decrease in G(t) from 8.22+/-1.15 to 4.41+/-1.00 mS x cm(-2) (P<0.01, N=27; means +/- S.E.M.). Control seawater-acclimated membranes had a density of apical crypts (where chloride cells are exposed to the environment; detected by scanning electron microscopy) of 1133+/-96.4 crypts x mm(-2) (N=12), whereas the hypotonically shocked specimens had a lower crypt density of 870+/-36.7 crypts x mm(-2) (P<0.01 N=10; means +/- S.E.M.). Hypertonic shock of freshwater membranes increased crypt density from 383.3+/-73.9 (N=12) to 630+/-102. 9 crypts x mm(-2) (P<0.05; N=11; means +/- S.E.M.). There was no change in density of chloride cells, as detected by fluorescence microscopy; hence, osmotic stress changes the degree of exposure, not the number of chloride cells. Cytochalasin D (5.0 micromol x l(-1)) completely blocked the conductance response to hypotonic shock and the reduction in apical crypt density measured by scanning electron microscopy, while phalloidin (33 micromol x l(-1)), colchicine (3x10(-4)mol x l(-1)) and griseofulvin (1.0 micromol x l(-1)) were ineffective. Actin imaging by phalloidin staining and confocal microscopy revealed extensive actin cords in pavement cell microridges and a ring of actin at the apex of chloride cells. We conclude that the actin cytoskeleton of chloride cells is required to maintain crypt opening and that osmotic shock causes chloride cells to adjust their apical crypt size.


Asunto(s)
Cloruros/metabolismo , Peces Killi/metabolismo , Aclimatación , Actinas/metabolismo , Animales , Citocalasina D/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/ultraestructura , Agua Dulce , Técnicas In Vitro , Peces Killi/anatomía & histología , Microscopía Confocal , Microscopía Electrónica , Concentración Osmolar , Presión Osmótica , Agua de Mar , Cloruro de Sodio
15.
J Endocrinol Invest ; 24(4): 209-16, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11383906

RESUMEN

New depot somatostatin analogs such as lanreotide-slow release (LAN) represent a significant improvement in the medical treatment of acromegaly. Seventy-three consecutive acromegalic patients, treated by LAN, were evaluated in a retrospective monocentric study. Sixteen were excluded from further evaluation due to combined treatment with dopamine agonist drugs, early LAN withdrawal for persistence of headache, or gastrointestinal side-effects. Fifty-seven patients (aged 20-82 years, 16 males) were thus evaluated. Thirty-two patients had been previously treated by neurosurgery (Tx) and/or radiotherapy (Rx). After washout, LAN (30 mg) was administered im at 10-14-day intervals. Time intervals between injections were then individually tailored to normalize IGF-I levels. LAN was administered for 12 (6-36) [median (range)] months. GH and IGF-I levels decreased from 13 (7-20) [median (interquartile)] microg/l to 3.2 (1.7-6.2) microg/l (p<0.0001) and from 780 (596-1000) microg/l to 264 (180-530) microg/l (p<0.000001), respectively. Seven patients were resistant to treatment. Among the 50 sensitive patients, GH levels fell below 2.5 microg/l in 52% (and below 1 microg/l in 18%), IGF-I levels normalized in 72% and both results were obtained in 46%. IGF-I values normalized in 87% of patients treated every 14 days, in 100% every 21-28 days, in 69% every 10 days and in 22% every 7 days. No different control of GH/IGF-I hypersecretion was evidenced between patients previously treated or not by Tx and/or Rx. Patients with the lowest basal hormonal levels and those over 55 years showed greater responsiveness (both p<0.05). The maintenance of LAN schedule up to 18 months determined a further suppression (p=0.04 for IGF-I). A reduction of tumor size was shown in 60% of evaluated patients (6/10). HbA1c slightly increased in 42% of patients and gallstones were observed in 16%. LAN is a very effective tool in the treatment of acromegaly: its chronic administration normalizes GH/IGF-I levels in most patients, shrinks the tumor in a high percentage of patients and seems to control hormonal hypersecretion as primary treatment as well as neurosurgery.


Asunto(s)
Acromegalia/tratamiento farmacológico , Antineoplásicos Hormonales/uso terapéutico , Hormona de Crecimiento Humana/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Péptidos Cíclicos/uso terapéutico , Neoplasias Hipofisarias/tratamiento farmacológico , Somatostatina/uso terapéutico , Acromegalia/etiología , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Hormonales/efectos adversos , Glucemia/metabolismo , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Péptidos Cíclicos/efectos adversos , Neoplasias Hipofisarias/complicaciones , Neoplasias Hipofisarias/patología , Estudios Retrospectivos , Somatostatina/efectos adversos , Somatostatina/análogos & derivados
16.
Neuroendocrinology ; 73(5): 344-51, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11399907

RESUMEN

Somatostatin (SRIH), a cyclic tetradecapeptide hormone originally isolated from mammalian hypothalamus, is a potent suppressor of pituitary growth hormone (GH) secretion. SRIH acts through a family of G-protein-coupled membrane receptors containing seven transmembrane domains. Five genes encoding distinct SRIH receptor (SSTR) subtypes have so far been cloned in human and other species and termed SSTR1-5. In human somatotrophe pituitary adenomas GH secretion is controlled by both SSTR2 and SSTR5. However, in clinical practice only somatostatin analogs selective for SSTR2 (octreotide and lanreotide) are available. This may explain why clinical and in vitro responses to these analogs in acromegaly are only partial. In this study, we investigated the inhibitory effect of two new SRIH analogs with high selectivity for SSTR2 (NC-4-28B) and SSTR5 (BIM-23268) and compared it to that of native somatostatin (SRIH-14) on a large number of GH-secreting adenomas obtained by transphenoidal neurosurgery. Tissues from 16 adenomas were enzymatically dispersed and plated in 24-well dishes at 50,000 cells/well. After 3 days, groups of three wells were incubated for 4 h with medium alone, SRIH-14 or analogs NC-4-28B or BIM-23268, at the concentrations of 0.01, 0.1 and 1 microM. Our results show that 9 out of 16 adenomas were responsive (GH suppression: 20-40% vs. control, p < 0.05) to SRIH. In this group only 4 adenomas showed similar responses to both selective analogs, with 2 nonresponders (expression of other SRIH receptor subtypes) and 2 responders (concomitant expression of SSTR2 and SSTR5) to both analogs. GH release was selectively inhibited by NC-4-28B in 3 adenomas and by BIM-23268 in the remaining 2 adenomas, suggesting predominant expression of SSTR2 and SSTR5, respectively. SRIH failed to inhibit GH release in 7 adenomas (43%). Interestingly, in that group a better inhibitory effect was obtained with BIM-23268 (5 out of 7 adenomas) than with NC-4-28B, suggesting expression of a few SSTR5 receptors only, or of both SSTR2 and SSTR5, respectively. We conclude that the availability of somatostatin analogs selective for SSTR5 will enhance the treatment potency and spectrum in acromegaly.


Asunto(s)
Adenoma/metabolismo , Hormona de Crecimiento Humana/metabolismo , Neoplasias Hipofisarias/metabolismo , Receptores de Somatostatina/fisiología , Somatostatina/análogos & derivados , Somatostatina/farmacología , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Femenino , Hormona de Crecimiento Humana/antagonistas & inhibidores , Humanos , Masculino , Persona de Mediana Edad , Receptores de Somatostatina/efectos de los fármacos
18.
Anticancer Res ; 21(6A): 3903-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11911267

RESUMEN

Oxidative stress due to oxygen and various radical species is associated with the induction of DNA single- and double-strand breaks and is considered to be a first step in several human degenerative diseases, cancer and ageing. Naturally occurring antioxidants are being extensively analysed for their ability to protect DNA against such injury. We studied three naturally occuring compounds, Ascorbic Acid, Melatonin and Ellagic acid, for their ability to modulate DNA damage produced by two strong radical oxygen inducers (H2O2 and Bleomycin) in cultured CHO cells. The alkaline Comet assay was used to measure DNA damage and a cytofluorimetric analysis was performed to reveal the intracellular oxidative species. The data showed a marked reduction of H2O2- and Bleomycin-induced DNA damage exerted by Ellagic Acid. On the contrary Ascorbic acid and Melatonin appeared to induce a slight increase in DNA damage per se. In combined treatments, they caused a slight reduction of H2O2-induced damage, but they did not efficiently modulate the Bleomycin-induced one. The Dichlorofluorescein diacetate (DCFH-DA) cytofluorimetric test confirmed the strong scavenging action exerted by Ellagic Acid.


Asunto(s)
Antioxidantes/farmacología , Ácido Elágico/farmacología , Animales , Ácido Ascórbico/farmacología , Bleomicina/metabolismo , Bleomicina/toxicidad , Células CHO/efectos de los fármacos , Células CHO/metabolismo , Ensayo Cometa , Cricetinae , Daño del ADN , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/toxicidad , Melatonina/farmacología , Oxidantes/metabolismo , Oxidantes/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Especies Reactivas de Oxígeno/toxicidad
19.
Environ Res ; 83(3): 311-21, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10944075

RESUMEN

In a program coordinated by the Italian Ministry of Works, we tested in vitro four pesticides widely employed in a developed agricultural region of central Italy. The four commercial agents were chosen on the basis of their diffusion in agricultural practice, knowledge of their active principle(s), and scant availability of data concerning their toxic and genotoxic activity. The agents were Cirtoxin, Decis, Tramat Combi (TC), and Lasso Micromix (LM). All substances were tested in three in vitro systems: Chinese hamster ovary (CHO) cells, a metabolically competent hamster cell line (Chinese hamster epithelial liver; CHEL), and root tips of Vicia faba (VF). The cytotoxic and genotoxic end points challenged were micronuclei and root tip length (RTL) in VF and mitotic index (MI), proliferation index (PI), cell survival (CS), cell growth (CG), cell cycle length (CCL), sister chromatid exchanges, chromosomal aberrations, and single-cell gel electrophoresis, or comet assay, in CHEL and CHO cells. Tested doses ranged from the field dose up to 200x the field dose to take into account accumulation effects. On the whole, tested agents appear to induce genotoxic damage only at subtoxic or toxic doses, indicating a low clastogenic risk. MI, PI, CS, CG, RTL, and CCL appear to be the less sensitive end points, showing no effects in the presence of a clear positive response in some or all of the other tests. Using cytogenetic tests, we obtained positive results for TC and LM treatments in CHO but not in CHEL cells. These data could be accounted for by postulating a detoxifying activity exerted by this cell line. However, cytogenetic end points appear to be more sensitive than those referring to cytotoxicity.


Asunto(s)
Ciclo Celular/efectos de los fármacos , Plaguicidas/toxicidad , Agricultura , Animales , Células CHO , Línea Celular , Supervivencia Celular , Ensayo Cometa , Cricetinae , Daño del ADN , Relación Dosis-Respuesta a Droga , Hígado/citología , Hígado/efectos de los fármacos , Micronúcleos con Defecto Cromosómico , Índice Mitótico , Pruebas de Mutagenicidad , Raíces de Plantas/efectos de los fármacos , Intercambio de Cromátides Hermanas
20.
J Endocrinol Invest ; 23(2): 107-11, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10800764

RESUMEN

Multiple pituitary hormone hypersecretions have been already described, but the combination of PRL and ACTH excess is rare. This report deals with a 42-yr-old woman affected by macroprolactinoma (PRL 12,720 microg/l, huge tumor with extrasellar extension at imaging). After one year on dopaminergic treatment causing PRL normalization and tumor shrinkage, she developed hypercortisolism (UFC 1,000 microg/24 h, ACTH 200 ng/l). Cushing's disease was diagnosed. After neurosurgery (at immunocytochemistry mixed ACTH-PRL adenoma was shown) hypercortisolism remitted, whereas pathological hyperprolactinemia with tumor remnant in cavernous sinus persisted and hypopituitarism developed. The patient reported seems atypical for the following reasons: 1) the concomitant PRL and ACTH hypersecretions; 2) the clinical presentation with hypercortisolism following hyperprolactinemia; 3) the surgical cure of hypercortisolism with persisting hyperprolactinemia.


Asunto(s)
Hormona Adrenocorticotrópica/metabolismo , Síndrome de Cushing/metabolismo , Neoplasias Hipofisarias/metabolismo , Prolactina/metabolismo , Prolactinoma/metabolismo , Hormona Adrenocorticotrópica/sangre , Adulto , Síndrome de Cushing/diagnóstico por imagen , Síndrome de Cushing/cirugía , Diabetes Insípida/etiología , Femenino , Humanos , Neoplasias Hipofisarias/diagnóstico por imagen , Neoplasias Hipofisarias/cirugía , Complicaciones Posoperatorias , Prolactina/sangre , Prolactinoma/diagnóstico por imagen , Prolactinoma/cirugía , Radiografía
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA