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1.
J Endocrinol Invest ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858278

RESUMEN

PURPOSE: To assess the occurrence and severity of SARS-CoV-2 infection/COVID-19, frequency of symptoms, clinical manifestations and behaviours in a sample of patients undergoing bariatric surgery (BS). METHODS: The EPICOVID19-BS is an observational cross-sectional study conducted in Italy during the second wave of the COVID-19 pandemic (September 2021-February 2022). Patients with severe/extreme obesity undergoing BS were asked to complete an online multiple-choice questionnaire and to provide additional clinical information and blood biochemistry. Positive COVID-19 cases were defined by the combination of positive nasopharyngeal swab test results and/or positive serological test results. Sociodemographic, clinical and behavioural characteristics were compared between positive and negative COVID-19 cases. RESULTS: A total of 745 participants were enrolled (mean age 44.5 ± 10.5 years SD, 78% female). The proportion of positive COVID-19 cases was 20.4%. They were more likely to be health care workers, to have close contacts with confirmed cases, to use anti-inflammatory drugs, to have immune system disorders, to have previous CMV infection, to have lower cholesterol levels and to have less metabolic syndrome than negative cases. Infected participants significantly increased their use of national health resources for minor health problems. The majority of participants experienced flu-like symptoms and taste and smell disturbances. Only 9.6% were hospitalised and none required intubation. CONCLUSIONS: Our results seem to support the evidence that patients undergoing BS have a low rate of severe SARS-CoV2. Further longitudinal studies in multiple obesity treatment centres are needed to more effectively monitor and control obesity in this specific population.

2.
Br J Surg ; 106(9): 1147-1155, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31233220

RESUMEN

BACKGROUND: Colonic J pouch reconstruction has been found to be associated with a lower incidence of anastomotic leakage than straight anastomosis. However, studies on this topic are underpowered and retrospective. This randomized trial evaluated whether the incidence of anastomotic leakage was reduced after colonic J pouch reconstruction compared with straight colorectal anastomosis following anterior resection for rectal cancer. METHODS: This multicentre RCT included patients with rectal carcinoma who underwent low anterior resection followed by colorectal anastomosis. Patients were assigned randomly to receive a colonic J pouch or straight colorectal anastomosis. The main outcome measure was the occurrence of major anastomotic leakage. The incidence of global (major plus minor) anastomotic leakage and general complications were secondary outcomes. Risk factors for anastomotic leakage were identified by regression analysis. RESULTS: Of 457 patients enrolled, 379 were evaluable (colonic J pouch arm 190, straight colorectal arm 189). The incidence of major and global anastomotic leakage, and general complications was 14·2, 19·5 and 34·2 per cent respectively in the colonic J pouch group, and 12·2, 19·0 and 27·0 per cent in the straight colorectal anastomosis group. No statistically significant differences were observed between the two arms. In multivariable logistic regression analysis, male sex (odds ratio 1·79, 95 per cent c.i. 1·02 to 3·15; P = 0·042) and high ASA fitness grade (odds ratio 2·06, 1·15 to 3·71; P = 0·015) were independently associated with the occurrence of anastomotic leakage. CONCLUSION: Colonic J pouch reconstruction does not reduce the incidence of anastomotic leakage and postoperative complications compared with conventional straight colorectal anastomosis. Registration number NCT01110798 (http://www.clinicaltrials.gov).


Asunto(s)
Colon/cirugía , Reservorios Cólicos , Procedimientos de Cirugía Plástica , Neoplasias del Recto/cirugía , Recto/cirugía , Grapado Quirúrgico , Anciano , Anastomosis Quirúrgica/efectos adversos , Anastomosis Quirúrgica/métodos , Fuga Anastomótica/epidemiología , Fuga Anastomótica/etiología , Reservorios Cólicos/efectos adversos , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/efectos adversos , Procedimientos de Cirugía Plástica/métodos , Grapado Quirúrgico/métodos
3.
Tech Coloproctol ; 21(8): 633-640, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28755256

RESUMEN

BACKGROUND: Rectum-sparing approaches appear to be appropriate in rectal cancer patients with a major (mCR) or complete clinical response (cCR) after neoadjuvant therapy. The aim of the present study is to evaluate the effectiveness of rectum-sparing approaches at 2 years after the completion of neoadjuvant treatment. STUDY DESIGN: Patients with rectal adenocarcinoma eligible to receive neoadjuvant therapy will be prospectively enrolled. Patients will be restaged 7-8 weeks after the completion of neoadjuvant therapy and those with mCR (defined as absence of mass, small mucosal irregularity no more than 2 cm in diameter at endoscopy and no metastatic nodes at MRI) or cCR will be enrolled in the trial. Patients with mCR will undergo local excision, while patients with cCR will either undergo local excision or watch and wait policy. The main end point of the study is to determine the percentage of rectum preservation at 2 years in the enrolled patients. CONCLUSION: This protocol is the first prospective trial that investigates the role of both local excision and watch and wait approaches in patients treated with neoadjuvant therapy for rectal cancer. The trial is registered at clinicaltrials.gov (NCT02710812).


Asunto(s)
Adenocarcinoma/terapia , Neoplasias del Recto/terapia , Espera Vigilante , Adenocarcinoma/cirugía , Quimioradioterapia Adyuvante , Quimioterapia Adyuvante , Humanos , Terapia Neoadyuvante , Tratamientos Conservadores del Órgano , Periodo Preoperatorio , Radioterapia Adyuvante , Neoplasias del Recto/cirugía , Recto , Proyectos de Investigación
4.
Tech Coloproctol ; 21(2): 139-147, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28194568

RESUMEN

BACKGROUND: The aim of this study was to identify risk factors for lymph node positivity in T1 colon cancer and to carry out a surgical quality assurance audit. METHODS: The sample consisted of consecutive patients treated for early-stage colon lesions in 15 colorectal referral centres between 2011 and 2014. The study investigated 38 factors grouped into four categories: demographic information, preoperative data, indications for surgery and post-operative data. A univariate and multivariate logistic regression analysis was performed to analyze the significance of each factor both in terms of lymph node (LN) harvesting and LN metastases. RESULTS: Out of 507 patients enrolled, 394 patients were considered for analysis. Thirty-five (8.91%) patients had positive LN. Statistically significant differences related to total LN harvesting were found in relation to central vessel ligation and segmental resections. Cumulative distribution demonstrated that the rate of positive LN increased starting at 12 LN harvested and reached a plateau at 25 LN. CONCLUSIONS: Some factors associated with an increase in detection of positive LN were identified. However, further studies are needed to identify more sensitive markers and avoid surgical overtreatment. There is a need to raise the minimum LN count and to use the LN count as an indicator of surgical quality.


Asunto(s)
Neoplasias del Colon/patología , Detección Precoz del Cáncer/estadística & datos numéricos , Escisión del Ganglio Linfático/estadística & datos numéricos , Ganglios Linfáticos/patología , Metástasis Linfática/diagnóstico , Adulto , Anciano , Neoplasias del Colon/etiología , Neoplasias del Colon/cirugía , Detección Precoz del Cáncer/métodos , Femenino , Humanos , Modelos Logísticos , Ganglios Linfáticos/cirugía , Masculino , Auditoría Médica , Uso Excesivo de los Servicios de Salud/estadística & datos numéricos , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Estudios Retrospectivos , Factores de Riesgo
5.
Tech Coloproctol ; 20(7): 455-9, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27164931

RESUMEN

BACKGROUND: The aim of our study was to assess the outcome of hemorrhoidal dearterialization, achieved by a dedicated laser energy device. METHODS: From November 2012 to December 2014, 51 patients with second- or third-degree hemorrhoids were studied. The primary end point was a reduction in the bleeding rate; secondary end points were: postoperative complications, reduction in pain and prolapse, resolution of symptoms, and degree of patient's perception of improvement. The procedure was carried out as 1-day surgery. A diode laser device was employed to seal the terminal branches of the hemorrhoidal arteries, detected by a Doppler-equipped proctoscope. Follow-up was scheduled at 1 and 4 weeks, 3, 12, and 24 months. The rate and degree of symptoms was assessed with a four-point verbal rating scale. The rate of subjective symptomatic improvement was also evaluated with the Patient Global Improvement (PGI) Scale. RESULTS: Mean bleeding and pain scores at baseline were 2 and 0.57. All the patients were discharged on the day of surgery. Postoperative complications were bleeding (n = 4) and external hemorrhoidal thrombosis (n = 4). Mean bleeding and pain scores at 3, 12, and 24 months were significatively reduced. After 24 months, complete resolution of bleeding was observed in 28/29 patients (96.7 %), resolution of pain in all patients, and resolution of the mucosal prolapse in 15/18 patients (76.9 %). At 12-month follow-up, 86.3 % of patients reported improvement with the PGI Scale. CONCLUSIONS: The hemorrhoid laser procedure was effective in improving bleeding and pain symptoms in patients with grade II and III hemorrhoids.


Asunto(s)
Hemorragia Gastrointestinal/prevención & control , Hemorreoidectomía/métodos , Hemorroides/cirugía , Láseres de Semiconductores/uso terapéutico , Dolor/prevención & control , Adolescente , Adulto , Anciano , Endosonografía , Femenino , Estudios de Seguimiento , Hemorragia Gastrointestinal/etiología , Hemorroides/complicaciones , Hemorroides/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Dolor/etiología , Proctoscopía , Prolapso , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Ultrasonografía Doppler , Adulto Joven
6.
Tech Coloproctol ; 20(5): 299-307, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27037709

RESUMEN

BACKGROUND: As stapled hemorrhoidopexy (SH) becomes more widely used, we see more patients with chronic postoperative anal pain after this surgery. Its presentation is variable and difficult to treat. The aim of our study was to investigate the impact of chronic anal pain after SH and whether tailored therapy was likely to achieve a favorable outcome. METHODS: We retrospectively analyzed 31 consecutive patients with chronic anal pain who had undergone SH in other hospitals and were referred to our institutions. Depending on the type of pain, unrelated (at rest) or related to defecation, two groups of patients were identified. Moreover, the mean distance of the staple line from the anal verge was calculated in both groups. Treatments included: topical nifedipine, local anesthetic and steroid infiltration, removal of retained staples, anal dilation, and scar excision with mucosal suturing. A visual analog scale (VAS) was used to compare pain at baseline, postoperatively, and in the follow-up. This mean difference of the VAS score between stages was always used as the main outcome measure, depending on the type of presentation, type of pain, and type of treatment. Treatment response was defined as a 50 % decrease of VAS from baseline. RESULTS: There were 22 males and 9 females. The overall median age was 43 years (range 21-62 years). On digital examination and proctoscopy, 15 (48 %) patients had inflammatory changes, 19 (61 %) patients had staple retention, 8 (26 %) patients had anorectal stenosis, and 30 (97 %) patients had scar tissue. All patients had one or more of the following treatments listed from the least to most invasive: topical nifedipine in 12 (39 %) patients, anal dilation in 6 (19 %) patients, anesthetic and steroid infiltration in 18 (58 %) patients, removal of staples in 10 (32 %) patients, and scar excision in 18 (58 %) patients. The mean VAS score at baseline was 6.100, ± 1.953 SD, which dropped significantly after treatment to 1.733, ± 1.658 SD (p < 0.001) and remained low at follow-up (1.741 ± SD 1.251; p < 0.743). In patients with pain at rest (n = 20, 65 %), the symptoms improved in 19 (95 %) patients, while the VAS score decreased from 5.552 ± 2.115 SD to 1.457 ± 1.440 SD (95 % CI 3.217-4.964; p < 0.001). In patients with post-evacuation pain (n = 11, 35 %), the symptoms improved in 11 (100 %) patients, while the VAS score decreased from 6.429 ± 1.835 SD to 1.891 ± 1.792 SD (95 % CI 3.784-5.269; p < 0.001). Rating of response based on presentation was 90.0 % (0.9/10) after treatment of staple retention, which led to a significant decrease in the mean VAS score from 6.304 ± 1.845 SD to 1.782 ± 1.731 SD (95 % CI 3.859-5.185; p < 0.001). Anal stenosis was successfully treated in 100.0 % (n = 8/8) of cases with the mean VAS score dropping from 6.500 ± 1.309 SD to 2.125 ± 1.808 SD (95 % CI 2.831-5.919; p < 0.001). Anal inflammation improved in 60.0 % (n = 9/15) of patients and the mean VAS score dropped from 6.006 ± 2.138 SD to 1.542 ± 1.457 SD (95 % CI 3.217-4.964; p < 0.001). The response after scar tissue treatment was 94 % (n = 17/18) of patients with a mean VAS decreasing from 6.117 ± 2.006 SD to 1.712 ± 1.697 SD (95 % CI 3.812-4.974; p < 0.001). Success for topical nifedipine was between 13 and 25 % of patients depending on the clinical presentation. Anal dilation was successful in 75 % of patients, while Anesthetic and steroid infiltration in 23-54 % of patients depending on the clinical presentation. Staple removal was successful in 77 % of patients, and scar excision with mucosal suturing in 94 % of patients. CONCLUSIONS: Our retrospective study suggests that most patients with chronic anal pain after SH may be cured with treatment by applying a stepwise approach from the least to the most invasive treatment.


Asunto(s)
Dolor Crónico/terapia , Hemorreoidectomía/efectos adversos , Hemorroides/cirugía , Dolor Postoperatorio/terapia , Suturas/efectos adversos , Adulto , Dolor Crónico/etiología , Femenino , Estudios de Seguimiento , Hemorreoidectomía/métodos , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Dolor Postoperatorio/etiología , Estudios Retrospectivos , Resultado del Tratamiento
8.
Tech Coloproctol ; 14(3): 229-35, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20632061

RESUMEN

BACKGROUND: There is good evidence that radiotherapy is beneficial in advanced rectal cancer, but its application in Italy has not been investigated. METHODS: We conducted a nationwide survey among members of the Italian Society of Colo-Rectal Surgery (SICCR) on the use of radiation therapy for rectal cancer in the year 2005. Demographic, clinical and pathologic data were retrospectively collected with an online database. Italy was geographically divided into 3 regions: north, center and south which included the islands. Hospitals performing 30 or more surgeries per year were considered high volume. Factors related to radiotherapy delivery were identified with multivariate analysis. RESULTS: Of 108 centers, 44 (41%) responded to the audit. We collected data on 682 rectal cancer patients corresponding to 58% of rectal cancers operated by SICCR members in 2005. Radiotherapy was used in 307/682 (45.0%) patients. Preoperative radiotherapy was used in 236/682 (34.6%), postoperative radiotherapy in 71/682 (10.4%) cases and no radiotherapy in 375 (55.0%) cases. Of the 236 patients who underwent preoperative radiotherapy, only 24 (10.2%) received short-course radiotherapy, while 212 (89.8%) received long-course radiotherapy. Of the 339 stage II-III patients, 159 (47%) did not receive any radiotherapy. Radiotherapy was more frequently used in younger patients (P < 0.0001), in patients undergoing abdominoperineal resection (APR) (P < 0.01) and in the north and center of Italy (P < 0.001). Preoperative radiotherapy was more frequently used in younger patients (P < 0.001), in large volume centers (P < 0.05), in patients undergoing APR (P < 0.005) and in the north-center of Italy (P < 0.05). CONCLUSION: Our study first identified a treatment disparity among different geographic Italian regions. A more systematic audit is needed to confirm these results and plan adequate interventions.


Asunto(s)
Auditoría Médica/métodos , Terapia Neoadyuvante , Neoplasias del Recto/mortalidad , Neoplasias del Recto/radioterapia , Anciano , Análisis de Varianza , Colectomía/métodos , Femenino , Estudios de Seguimiento , Encuestas de Atención de la Salud , Humanos , Italia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Invasividad Neoplásica/patología , Estadificación de Neoplasias , Oportunidad Relativa , Dosificación Radioterapéutica , Radioterapia Adyuvante , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento
11.
Mol Cell Endocrinol ; 247(1-2): 135-9, 2006 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-16414177

RESUMEN

Hesx1 is a paired-like homeobox gene first expressed during mouse embryogenesis in the anterior midline visceral endoderm. As gastrulation proceeds, Hesx1 is expressed in the ventral prosencephalon and, subsequently, at E9.0 appears in the ventral diencephalon and in the thickened layer of oral ectoderm that give rise to Rathke's pouch, the primordium of the anterior pituitary gland. Hesx1 continues to be expressed in the developing anterior pituitary until E11.5 when its transcripts disappear in a spatiotemporal sequence corresponding to progressive pituitary cell differentiation, becoming undetectable by E15.5. In the present study, we investigated whether HESX1 is expressed during adult life in human normal pituitaries and in different types of human pituitary adenomas. We analysed, using quantitative RT-PCR method, three normal pituitaries, seven GH-, two TSH-, two PRL-, one ACTH-secreting adenomas, and seven nonfunctioning pituitary tumors. HESX1 mRNA was found to be expressed in normal pituitaries and in all the pituitary tumors that we have analysed. These results suggest that in humans HESX1 is not turned-off during the adult life as it occurs in mice. Thus, HESX1 in humans might play a role in the maintenance of the anterior pituitary cell types and function, as well as in the differentiation of pituitary adenomas, whose pathogenetic mechanisms remain to be further investigated. This is the first study on HESX1 expression in humans during adult life.


Asunto(s)
Adenoma/metabolismo , Proteínas de Homeodominio/biosíntesis , Hipófisis/metabolismo , Neoplasias Hipofisarias/metabolismo , Hormona Adrenocorticotrópica/metabolismo , Adulto , Anciano , Femenino , Hormona de Crecimiento Humana/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Hipófisis/patología , Prolactina/metabolismo , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tirotropina/metabolismo
12.
J Clin Endocrinol Metab ; 77(2): 393-8, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8345043

RESUMEN

Carbohydrate structures of intrapituitary and circulating TSH were studied by Concanavalin-A (Con A) and ricin lectin chromatography under different clinical conditions. Con A permits the separation of molecules differing in the extent of their carbohydrate branching, whereas ricin gives an estimation of the degree of their sialylation. Intrapituitary TSH was more retained on Con A and less sialylated than circulating hormone, suggesting that carbohydrate chains of intrapituitary molecules are less mature than those present in the circulation. A greater proportion of TSH firmly bound to Con A, compared to control values, was found in sera from fetuses and patients with uremia, TSH-secreting adenomas, and central hypothyroidism. In primary hypothyroid patients, TSH binding to Con A was similar to that found in controls, but a greater percentage of sialylated forms was seen. In central hypothyroidism patients, TSH released in response to TRH was less sialylated. Interestingly, no sialylated TSH was found in normal fetuses. In conclusion, the present data show that both TSH carbohydrate branching and sialylation may vary in different clinical conditions. As some of the above clinical conditions are known to be accompanied by variations in the bioactivity of circulating TSH, the finding of changes in TSH carbohydrate structures further supports the view that glycosylation modulates the expression of TSH biological activity.


Asunto(s)
Carbohidratos/química , Tirotropina/química , Adenoma/metabolismo , Cromatografía de Afinidad , Concanavalina A , Femenino , Feto/metabolismo , Humanos , Hipotiroidismo/metabolismo , Focalización Isoeléctrica , Masculino , Estructura Molecular , Hipófisis/química , Hipófisis/embriología , Hipófisis/metabolismo , Neoplasias Hipofisarias/metabolismo , Embarazo/metabolismo , Ricina , Tirotropina/biosíntesis , Uremia/metabolismo
13.
J Clin Endocrinol Metab ; 76(4): 1008-13, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8473374

RESUMEN

We have studied the carbohydrate of circulating human gonadotropins (FSH and LH) in different clinical conditions using Concanavalin A (Con A) affinity chromatography. This technique permits separation of molecules differing in the extent of carbohydrate branching. The proportion of molecules that does not bind to Con A was greater in circulating FSH than in LH, reflecting a higher content of multiantennary and/or bisected biantennary complex carbohydrate structures in serum FSH. No significant difference in gonadotropin binding pattern to Con A was found between normal controls and patients with chronic uremia or gonadotropin-secreting pituitary adenomas. On the contrary, sera from postmenopausal women and fetuses contained a greater proportion of FSH and LH that bound to Con A, indicating a shift from multiantennary and/or bisecting structures to hybrid and/or high mannose forms, i.e. to the secretion of less mature forms. International Reference Preparations, derived from pituitary extracts, were more retained on Con A than circulating hormones, suggesting that carbohydrate chains of the intrapituitary hormone stock are less mature than those present in the circulation. Less mature forms were also found in FSH, but not in LH, from normal controls after GnRH injection. Finally, a higher proportion of unbound forms, i.e. complex carbohydrate chains, was found in healthy subjects presenting with an immunologically anomalous variant of LH. In conclusion, the current data show that the hormonal status of the individual may differently affect carbohydrate branching of gonadotropins. Alteration in glycosylation is likely to be involved in masking at least one epitope specific for intact LH dimer, thus indicating that it may modulate the tertiary structure of glycoprotein hormones.


Asunto(s)
Gonadotropinas/sangre , Adulto , Conformación de Carbohidratos , Cromatografía de Afinidad , Concanavalina A , Femenino , Hormona Folículo Estimulante/sangre , Gonadotropinas/química , Gonadotropinas/metabolismo , Humanos , Focalización Isoeléctrica , Hormona Luteinizante/sangre , Masculino , Persona de Mediana Edad , Hipófisis/metabolismo , Valores de Referencia
14.
J Clin Endocrinol Metab ; 80(9): 2722-8, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7673415

RESUMEN

Circadian rhythm of TSH secretion is characterized by a pronounced nocturnal increment that is not followed by the expected rise of circulating thyroid hormone levels. These findings suggest that the nocturnal TSH surge may be constituted by molecules with reduced bioactivity. We, therefore, investigated TSH bioactivity (measured as cAMP accumulation in FRTL-5 cells) and its carbohydrate structure (by Concanavalin A affinity chromatography) in different blood pools taken during the day and night from seven normal subjects and from one patient with mild (mPH) and five with severe primary hypothyroidism (sPH). Patients with sPH were also studied during low dose L-T4 treatment. Cosinor analysis showed a significant TSH circadian rhythm in the control group and in L-T4-treated sPH patients. The nocturnal TSH surge was not followed by any increase in free thyroid hormone levels. In normal subjects, the daytime ratio of TSH bioactivity to immunoreactivity (TSH B/I) was higher than the nocturnal one [1.4 +/- 0.6 (+/- SD) vs. 1.1 +/- 0.6; P < 0.02]. The same pattern was observed in the only mPH patient (1.0 +/- 0.2 vs. 0.7 +/- 0.1; P < 0.01), but not in the sPH patients (0.8 +/- 0.3 vs. 0.7 +/- 0.1; P = 0.3). L-T4 administration to sPH patients caused the daytime TSH B/I to increase and restored the day/night difference in the TSH B/I (1.0 +/- 0.3 vs. 0.8 +/- 0.3; P < 0.02). Concanavalin A chromatography showed that a higher percentage of less mature forms of TSH are secreted during the night. These data indicate that TSH molecules secreted during the night are less bioactive and differently glycosylated than those circulating in the same individual during the day, thus explaining why thyroid hormone levels do not rise after the nocturnal TSH surge. In sPH patients, the TSH circadian rhythm is restored during L-T4 administration, and day/night differences in TSH B/I similar to those recorded in normal subjects are observed.


Asunto(s)
Ritmo Circadiano , Hipotiroidismo/sangre , Tirotropina/sangre , Adulto , Anciano , Bioensayo , Cromatografía de Afinidad , Concanavalina A/metabolismo , Femenino , Humanos , Hipotiroidismo/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Valores de Referencia , Hormonas Tiroideas/sangre , Tirotropina/metabolismo , Tiroxina/uso terapéutico
15.
J Clin Endocrinol Metab ; 83(7): 2486-92, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9661632

RESUMEN

Variation in asparagine-linked carbohydrate chains have a major impact on TSH biological properties. In particular, highly sialylated TSH is characterized by impaired intrinsic bioactivity and prolonged half-life. The aim of the present study was to investigate the changes in the degree of sialylation of circulating TSH isoforms that may occur in several physiological and clinical situations. Bioactivity and terminal sugar residues of immunopurified TSH were studied in 26 normal adults (day- and nighttime serum pools), 2 cord serum pools from normal fetuses during the third trimester, 1 fetus with primary hypothyroidism (PH; 27th week), 1 fetus with resistance to thyroid hormone (RTH; 28th and 33rd weeks), 24 patients with PH (before and during L-T4 treatment), and 5 patients with RTH before and during triiodothyrocetic acid (TRIAC) treatment. Nighttime TSH isoforms have an increased degree of sialylation compared to daytime TSH (35.8 +/- 9.7% vs. 23.8 +/- 5.8%; P < 0.03), thus accounting for the lower bioactivity [biological/immunological TSH ratio (TSH B/I), 1.3 +/- 0.4 vs. 2.0 +/- 0.2; P < 0.0007]. In adult PH, TSH isoforms are highly sialylated (45.4 +/- 7.6%; P < 0.007), showing an impaired bioactivity (0.7 +/- 0.3; P < 0.001). L-T4 therapy was accompanied by a trend toward normalization of TSH biological properties; TSH B/I was higher (1.0 +/- 0.3; P < 0.01), and the degree of sialylation was lower (36.8 +/- 7.0%; P < 0.02). A significant inverse correlation between TSH B/I values and the degree of sialylation was observed (P < 0.001). In normal fetuses, extremely bioactive asialo-TSH isoforms are circulating during the 3rd trimester. The impaired thyroid hormone action, such as that occurring in hypothyroid or RTH fetuses, induces an early expression of alpha-2,6-sialyltransferase activity within thyrotropes and results in the secretion of high amounts of sialylated TSH isoforms (34.6% and 26.3%). A hybrid TSH with peculiar terminal sugar residues and enhanced bioactivity is circulating in patients with RTH (TSH B/I, > or = 2.2). Treatment with low doses of TRIAC can initially reduce thyroid hormone secretion in RTH, mainly through the secretion of TSH isoforms with changed terminal sugar residues and reduced bioactivity (TSH B/I, 0.9-1.7). In conclusion, changes in the terminal sialic acid residues modulate the biological properties of circulating TSH, play a relevant physiopathological role in various situations, and contribute to adjust thyroid-stimulating activity to temporary needs.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Sangre Fetal/metabolismo , Hipotiroidismo/sangre , Ácidos Siálicos/metabolismo , Síndrome de Resistencia a Hormonas Tiroideas/sangre , Tirotropina/sangre , Adolescente , Adulto , Animales , Células CHO , Estudios de Casos y Controles , Línea Celular , Cricetinae , Desarrollo Embrionario y Fetal/fisiología , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Embarazo , Tercer Trimestre del Embarazo , Valores de Referencia
16.
J Clin Endocrinol Metab ; 78(5): 1034-9, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8175956

RESUMEN

Resistance to thyroid hormone (RTH) is a rare genetic disorder associated with diverse mutations in the thyroid hormone receptor beta-gene. TSH-dependent thyroid hyperstimulation, leading to goiter and elevated thyroid hormone levels, is a characteristic feature of RTH. However, about 60% of untreated resistance patients have circulating TSH levels within the normal range, raising the possibility that the biological activity of TSH is altered. We, therefore, assayed the bioactivity of circulating TSH in 11 patients from 8 different kindreds with RTH, measuring cAMP production in Chinese hamster ovary cells transfected with the recombinant human TSH receptor as well as in FRTL-5 cells. The ratio of biologically active vs. immunoreactive TSH (B/I) was significantly higher in RTH patients than in 8 normal controls [TSH B/I, 4.2 +/- 0.9 (range, 2.2-11.9) vs. 1.3 +/- 0.2 (range, 0.6-2.1)]. TSH released in response to TRH had a bioactivity similar to that of circulating TSH under basal conditions. On the contrary, supraphysiological doses of T3 normalized the B/I ratio of circulating TSH. Concanavalin-A chromatography of TSH from RTH patients showed the presence of circulating forms with altered carbohydrate branching. Our data indicate that the bioactivity of circulating TSH in thyroid hormone resistance syndromes is enhanced and can be normalized after T3 administration. These findings may account for the occurrence of goiter and elevated thyroid hormone levels in RTH patients despite normal serum TSH concentrations.


Asunto(s)
Bocio/genética , Receptores de Hormona Tiroidea/genética , Hormonas Tiroideas/sangre , Tirotropina/metabolismo , Adulto , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Síndrome
17.
J Clin Endocrinol Metab ; 82(4): 1094-100, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9100579

RESUMEN

The TSH receptor is a G protein-coupled receptor that mediates the effects of TSH in thyroid development, growth, and synthetic function. We report here that a child with features of TSH resistance, including markedly increased serum TSH concentrations and low normal thyroid hormone levels, is a compound heterozygote for two novel mutations in the TSH receptor gene. One allele has a G to A transition corresponding to an arginine to glutamine change at codon 109 (R109Q) in the extracellular domain of the receptor. The other allele has a G to A transition corresponding to a premature termination codon at tryptophan 546 (W546X) in the fourth transmembrane segment. Each parent is heterozygous for one mutation, and both parents have normal thyroid function. Cells transiently transfected with the R109Q mutant exhibited reduced membrane binding of [125I]TSH and impaired signal transduction in response to TSH. In contrast, the W546X mutant was nonfunctional, with negligible membrane radioligand binding. Our findings indicate that a single normal TSH receptor allele is sufficient for normal thyroid function, but that the compound abnormality in the proband leads to TSH resistance.


Asunto(s)
Mutación , Receptores de Tirotropina/genética , Tirotropina/fisiología , Secuencia de Aminoácidos , Animales , Células CHO/metabolismo , Cricetinae , Resistencia a Medicamentos/genética , Heterocigoto , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Datos de Secuencia Molecular , Hipófisis/patología , Receptores de Tirotropina/metabolismo , Proteínas Recombinantes , Pruebas de Función de la Tiroides , Tirotropina/sangre
18.
J Clin Endocrinol Metab ; 82(12): 3933-40, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9398691

RESUMEN

Resistance to TSH (RTSH) is a recently described syndrome of reduced sensitivity to TSH that manifests as euthyroid hyperthyrotropinemia. It is usually identified at birth during routine neonatal screening for congenital hypothyroidism. In less than 2 yr, 13 subjects with RTSH belonging to 8 families have been reported, and all were shown to harbor mutations in the TSH receptor (TSHR) gene. We now report the occurrence of RTSH in 3 unrelated families. Contrary to previous reports, the inheritance of RTSH in 2 of the families was dominant rather than recessive and was not associated with abnormalities in the TSHR gene. Abnormalities in the TSHR gene were excluded by sequencing all coding sequences, exon/intron junctions, and the promoter region of the gene. Furthermore, the involvement of the TSHR in the manifestation of the RTSH phenotype was excluded in 2 families by linkage analysis using intragenic polymorphic markers. We excluded defects in the TSH beta-subunit by sequencing its gene and by showing that the circulating TSH in affected subjects from all families had normal bioactivity. Also, no abnormalities were found in the Gs alpha gene of one family analyzed by GC-clamped denaturing gradient gel electrophoresis. This study shows that RTSH may be a manifestation of several different genetic defects that requires the exploration of other candidate genes involved in the TSH-TSHR-Gs alpha cascade and genes participating in its regulation.


Asunto(s)
Mutación/fisiología , Receptores de Tirotropina/genética , Tirotropina/genética , Tirotropina/fisiología , Adulto , Secuencia de Bases , Niño , Resistencia a Medicamentos/genética , Glándulas Endocrinas/fisiopatología , Femenino , Proteínas de Unión al GTP/genética , Ligamiento Genético , Haplotipos , Humanos , Recién Nacido , Masculino , Linaje , Fenotipo , Glándula Tiroides/fisiopatología
19.
J Clin Endocrinol Metab ; 84(2): 405-10, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10022392

RESUMEN

A 29-yr-old woman with pituitary resistance to thyroid hormones (PRTH) was found to harbor a novel point mutation (T337A) on exon 9 of the thyroid hormone receptor beta (TRbeta) gene. She presented with symptoms and signs of hyperthyroidism and was successfully treated with 3,5,3'-triiodothyroacetic acid (TRIAC) until the onset of pregnancy. This therapy was then discontinued in order to prevent TRIAC, a compound that crosses the placental barrier, from exerting adverse effects on normal fetal development. However, as the patient showed a recurrence of thyrotoxic features after TRIAC withdrawal, we sought to verify, by means of genetic analysis and hormone measurements, whether the fetus was also affected by RTH, in order to rapidly reinstitute TRIAC therapy, which could potentially be beneficial to both the mother and fetus. At 17 weeks gestation, fetal DNA was extracted from chorionic villi and was used as a template for PCR and restriction analysis together with direct sequencing of the TRbeta gene. The results indicated that the fetus was also heterozygous for the T337A mutation. Accordingly, TRIAC treatment at a dose of 2.1 mg/day was restarted at 20 weeks gestation. The mother rapidly became euthyroid, and the fetus grew normally up to 24 weeks gestation. At 29 weeks gestation mild growth retardation and fetal goiter were observed, prompting cordocentesis. Circulating fetal TSH was very high (287 mU/L) with a markedly reduced TSH bioactivity (B/I: 1.1 +/- 0.4 vs 12.7 +/- 1.2), while fetal FT4 concentrations were normal (8.7 pmol/L; normal values in age-matched fetuses: 5-22 pmol/L). Fetal FT3 levels were raised (7.1 pmol/L; normal values in age-matched fetuses: <4 pmol/L), as a consequence of 100% cross-reactivity of TRIAC in the FT3 assay method. To reduce the extremely high circulating TSH levels and fetal goiter, the dose of TRIAC was increased to 3.5 mg/day. To monitor the possible intrauterine hypothyroidism, another cordocentesis was performed at 33 weeks gestation, showing that TSH levels were reduced by 50% (from 287 to 144 mU/L). Furthermore, a simultaneous ultrasound examination revealed a clear reduction in fetal goiter. After this latter cordocentesis, acute complications occured, prompting delivery by cesarean section. The female neonate was critically ill, with multiple-organ failure and respiratory distress syndrome. In addition, a small goiter and biochemical features ofhypothyroidism were noted transiently and probably related to the prematurity of the infant. At present, the baby is clinically euthyroid, without goiter, and only exhibits biochemical features of RTH. In summary, although further fetal studies in cases of RTH are necessary to determine whether elevated TSH levels with a markedly reduced bioactivity are a common finding, our data suggest transient biochemical hypothyroidism in RTH during fetal development. Furthermore, we advocate prenatal diagnosis of RTH and adequate treatment of the disease in case of maternal hyperthyroidism, to avoid fetal thyrotrope hyperplasia, reduce fetal goiter, and maintain maternal euthyroidism during pregnancy.


Asunto(s)
Enfermedades Fetales/diagnóstico , Complicaciones del Embarazo , Diagnóstico Prenatal , Síndrome de Resistencia a Hormonas Tiroideas/diagnóstico , Adulto , ADN/análisis , Femenino , Sangre Fetal/química , Enfermedades Fetales/tratamiento farmacológico , Edad Gestacional , Heterocigoto , Humanos , Mutación , Embarazo , Síndrome de Resistencia a Hormonas Tiroideas/tratamiento farmacológico , Síndrome de Resistencia a Hormonas Tiroideas/genética , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/análogos & derivados , Triyodotironina/sangre , Triyodotironina/uso terapéutico
20.
Eur J Endocrinol ; 143(3): 347-52, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11022176

RESUMEN

BACKGROUND: One of the causes of combined pituitary hormone deficiency (CPHD) is represented by Prophet of Pit-1 (PROP-1) gene inactivating mutations. This disorder is generally characterized by GH, TSH, prolactin (PRL), and gonadotropin deficiency, but recent papers have described a concomitant alteration of the corticotrope function. OBJECTIVE: To make a detailed investigation of the hypothalamic-pituitary-adrenal axis in two sisters with PROP-1 gene mutations. PATIENTS: Two female siblings (17 and 16 years old) with CPHD, belonging to a Brazilian family of consanguineous parents, presented with growth retardation and central hypothyroidism during childhood, and showed central hypogonadism at the age of puberty. No clear clinical symptoms and signs of hypocortisolism were present. METHODS: GH, TSH, free thyroxine, total tri-iodothyronine, PRL, LH, FSH, ACTH and cortisol were measured in basal condition and after appropriate testing. The molecular study was performed by PCR amplification and sequencing analysis of PROP-1 gene. RESULTS: Both patients showed GH, PRL, LH and FSH deficiencies, associated with absent responses to an insulin tolerance test (ITT), TRH and GnRH injection. Circulating concentrations of TSH were normal in basal conditions, but failed to respond to a TRH test. Plasma ACTH concentrations were normal, but serum cortisol concentrations were below the lower limit of the normal range, showing a trend to decrease during 6 years of follow-up. The serum ACTH response to ITT was impaired, whereas its response to CRH was normal and prolonged. The cortisol response to both tests, and to the ACTH test, was clearly impaired. In both sisters, the genetic analysis showed the presence of a homozygous 2-bp deletion (296delGA) of PROP-1 gene, which results in the synthesis of a protein with no residual functional activity. CONCLUSION: In addition to GH, TSH, PRL and gonadotropin deficiency, patients with PROP-1 gene mutations can present with late-onset central hypocortisolism, possibly beause of the lack of important paracrine factors normally produced by the cells surrounding the corticotropes and absent in the pituitary of these patients, or because of progressive corticotrope apoptosis. This finding indicates the need for life-long endocrine monitoring of PROP-1-deficient patients.


Asunto(s)
Proteínas de Homeodominio/genética , Hidrocortisona/deficiencia , Hipopituitarismo/genética , Hormonas Hipofisarias/deficiencia , Adolescente , Linaje de la Célula , Femenino , Humanos , Hidrocortisona/sangre , Hipopituitarismo/metabolismo , Mutación , Fenotipo , Hormonas Hipofisarias/sangre , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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