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1.
Antib Ther ; 6(4): 277-297, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38075238

RESUMEN

Background: Due to COVID-19, pandemic preparedness emerges as a key imperative, necessitating new approaches to accelerate development of reagents against infectious pathogens. Methods: Here, we developed an integrated approach combining synthetic, computational and structural methods with in vitro antibody selection and in vivo immunization to design, produce and validate nature-inspired nanoparticle-based reagents against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Results: Our approach resulted in two innovations: (i) a thermostable nasal vaccine called ADDoCoV, displaying multiple copies of a SARS-CoV-2 receptor binding motif derived epitope and (ii) a multivalent nanoparticle superbinder, called Gigabody, against SARS-CoV-2 including immune-evasive variants of concern (VOCs). In vitro generated neutralizing nanobodies and electron cryo-microscopy established authenticity and accessibility of epitopes displayed by ADDoCoV. Gigabody comprising multimerized nanobodies prevented SARS-CoV-2 virion attachment with picomolar EC50. Vaccinating mice resulted in antibodies cross-reacting with VOCs including Delta and Omicron. Conclusion: Our study elucidates Adenovirus-derived dodecamer (ADDomer)-based nanoparticles for use in active and passive immunization and provides a blueprint for crafting reagents to combat respiratory viral infections.

2.
J Clin Endocrinol Metab ; 98(7): 2716-24, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23678038

RESUMEN

CONTEXT: The long-term effects of pure 17ß-estradiol (E2) depending on route of administration have not been well characterized. OBJECTIVE: Our objective was to assess metabolic effects of oral vs transdermal (TD) 17ß-E2 replacement using estrogen concentration-based dosing in girls with Turner syndrome (TS). PATIENTS: Forty girls with TS, mean age 16.7 ± 1.7 years, were recruited. DESIGN: Subjects were randomized to 17ß-E2 orally or TD. Doses were titrated using mean E2 concentrations of normally menstruating girls as therapeutic target. E2, estrone (E1), and E1 sulfate (E1S) were measured by liquid chromatography tandem mass spectrometry and a recombinant cell bioassay; metabolites were measured, and dual-energy x-ray absorptiometry scan and indirect calorimetry were performed. MAIN OUTCOME: Changes in body composition and lipid oxidation were evaluated. RESULTS: E2 concentrations were titrated to normal range in both groups; mean oral dose was 2 mg, and TD dose was 0.1 mg. After 6 and 12 months, fat-free mass and percent fat mass, bone mineral density accrual, lipid oxidation, and resting energy expenditure rates were similar between groups. IGF-1 concentrations were lower on oral 17ß-E2, but suppression of gonadotropins was comparable with no significant changes in lipids, glucose, osteocalcin, or highly sensitive C-reactive protein between groups. However, E1, E1S, SHBG, and bioestrogen concentrations were significantly higher in the oral group. CONCLUSIONS: When E2 concentrations are titrated to the normal range, the route of delivery of 17ß-E2 does not affect differentially body composition, lipid oxidation, and lipid concentrations in hypogonadal girls with TS. However, total estrogen exposure (E1, E1S, and total bioestrogen) is significantly higher after oral 17ß-E2. TD 17ß-E2 results in a more physiological estrogen milieu than oral 17ß-E2 administration in girls with TS.


Asunto(s)
Metabolismo Energético/efectos de los fármacos , Estradiol/administración & dosificación , Terapia de Reemplazo de Estrógeno , Síndrome de Turner/tratamiento farmacológico , Administración Oral , Adolescente , Adulto , Metabolismo Basal/efectos de los fármacos , Biotransformación , Composición Corporal/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Monitoreo de Drogas , Estradiol/sangre , Estradiol/farmacocinética , Estradiol/uso terapéutico , Estrona/análogos & derivados , Estrona/sangre , Estudios de Factibilidad , Femenino , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Parche Transdérmico , Síndrome de Turner/sangre , Síndrome de Turner/metabolismo , Adulto Joven
3.
J Clin Endocrinol Metab ; 96(2): E404-12, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21147883

RESUMEN

CONTEXT: Léri-Weill dyschondrosteosis (LWD) is a skeletal dysplasia characterized by disproportionate short stature and the Madelung deformity of the forearm. SHOX mutations and pseudoautosomal region 1 deletions encompassing SHOX or its enhancers have been identified in approximately 60% of LWD and approximately 15% of idiopathic short stature (ISS) individuals. Recently SHOX duplications have been described in LWD/ISS but also in individuals with other clinical manifestations, thus questioning their pathogenicity. OBJECTIVE: The objective of the study was to investigate the pathogenicity of SHOX duplications in LWD and ISS. DESIGN AND METHODS: Multiplex ligation-dependent probe amplification is routinely used in our unit to analyze for SHOX/pseudoautosomal region 1 copy number changes in LWD/ISS referrals. Quantitative PCR, microsatellite marker, and fluorescence in situ hybridization analysis were undertaken to confirm all identified duplications. RESULTS: During the routine analysis of 122 LWD and 613 ISS referrals, a total of four complete and 10 partial SHOX duplications or multiple copy number (n > 3) as well as one duplication of the SHOX 5' flanking region were identified in nine LWD and six ISS cases. Partial SHOX duplications appeared to have a more deleterious effect on skeletal dysplasia and height gain than complete SHOX duplications. Importantly, no increase in SHOX copy number was identified in 340 individuals with normal stature or 104 overgrowth referrals. CONCLUSION: MLPA analysis of SHOX/PAR1 led to the identification of partial and complete SHOX duplications or multiple copies associated with LWD or ISS, suggesting that they may represent an additional class of mutations implicated in the molecular etiology of these clinical entities.


Asunto(s)
Estatura/genética , Proteínas de Homeodominio/genética , Estudios de Cohortes , ADN/genética , Bases de Datos de Ácidos Nucleicos , Enanismo/genética , Femenino , Dosificación de Gen , Duplicación de Gen , Trastornos del Crecimiento/genética , Humanos , Hibridación Fluorescente in Situ , Masculino , Repeticiones de Microsatélite , Técnicas de Amplificación de Ácido Nucleico , Osteocondrodisplasias/genética , Linaje , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína de la Caja Homeótica de Baja Estatura , España
4.
J Clin Endocrinol Metab ; 93(11): 4210-7, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18782877

RESUMEN

OBJECTIVE: Our objective was to summarize important advances in the management of children with idiopathic short stature (ISS). PARTICIPANTS: Participants were 32 invited leaders in the field. EVIDENCE: Evidence was obtained by extensive literature review and from clinical experience. CONSENSUS: Participants reviewed discussion summaries, voted, and reached a majority decision on each document section. CONCLUSIONS: ISS is defined auxologically by a height below -2 sd score (SDS) without findings of disease as evident by a complete evaluation by a pediatric endocrinologist including stimulated GH levels. Magnetic resonance imaging is not necessary in patients with ISS. ISS may be a risk factor for psychosocial problems, but true psychopathology is rare. In the United States and seven other countries, the regulatory authorities approved GH treatment (at doses up to 53 microg/kg.d) for children shorter than -2.25 SDS, whereas in other countries, lower cutoffs are proposed. Aromatase inhibition increases predicted adult height in males with ISS, but adult-height data are not available. Psychological counseling is worthwhile to consider instead of or as an adjunct to hormone treatment. The predicted height may be inaccurate and is not an absolute criterion for GH treatment decisions. The shorter the child, the more consideration should be given to GH. Successful first-year response to GH treatment includes an increase in height SDS of more than 0.3-0.5. The mean increase in adult height in children with ISS attributable to GH therapy (average duration of 4-7 yr) is 3.5-7.5 cm. Responses are highly variable. IGF-I levels may be helpful in assessing compliance and GH sensitivity; levels that are consistently elevated (>2.5 SDS) should prompt consideration of GH dose reduction. GH therapy for children with ISS has a similar safety profile to other GH indications.


Asunto(s)
Trastornos del Crecimiento/diagnóstico , Trastornos del Crecimiento/terapia , Adulto , Estatura , Peso Corporal , Niño , Endocrinología/métodos , Femenino , Hormona Liberadora de Gonadotropina/uso terapéutico , Trastornos del Crecimiento/clasificación , Trastornos del Crecimiento/psicología , Humanos , Factor I del Crecimiento Similar a la Insulina/deficiencia , Masculino , Tamizaje Masivo , Valores de Referencia
5.
J Vasc Access ; 6(2): 64-71, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16552687

RESUMEN

This is a literature review which approaches the problem of successful use of arteriovenous fistulas for dialysis within the construct of Virchow's triad. By organizing the literature with regard to Virchow's concepts of blood flow, vascular injury, and thrombophilia an improved understanding arteriovenous fistula placement, maintenance and repair can be obtained. This process is designed to increase understanding and options for treatment by looking at this problem and using scientific knowledge gained in cardiology, oncology and vascular surgery medicine. Future approaches to fistulas will hopefully be a multifaceted and based in cellular pathophysiology as well as surgical and radiologic interventions and repairs.

6.
Neurology ; 58(2): 218-25, 2002 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-11805247

RESUMEN

BACKGROUND: Turner syndrome (TS) has a characteristic neurocognitive profile. Verbal abilities are, in general, normal; however, women with TS, as a group, have specific deficits in visual-spatial abilities, visual-perceptual abilities, motor function, nonverbal memory, executive function, and attentional abilities. Observed deficits could be caused by genetic or endocrine factors. OBJECTIVE: To evaluate the specific cognitive deficits that appear to persist in adulthood, are not estrogen-responsive, and may be genetically determined. METHODS: The cognitive performance of adult women with TS (n = 71) who were estrogen repleted was compared with verbal IQ- and socioeconomic status-matched female controls (n = 50). Sixty-one women with TS had ovarian failure and received estrogen replacement and 10 had preserved endogenous ovarian function and were not receiving estrogen replacement at the time of evaluation. RESULTS: Similar to children and adolescents with TS, adults with TS have normal verbal IQ but have relative difficulty on measures of spatial/perceptual skills, visual-motor integration, affect recognition, visual memory, attention, and executive function despite estrogen replacement. These deficits are apparent in women with TS despite apparently adequate estrogen effect, either endogenous or by hormone replacement. CONCLUSION: The cognitive phenotypes of adults with TS, with or without ovarian failure, are similar, indicating that estrogen replacement does not have a major impact on the cognitive deficits of adults with TS.


Asunto(s)
Trastornos del Conocimiento/etiología , Síndrome de Turner/fisiopatología , Adolescente , Adulto , Atención/fisiología , Niño , Trastornos del Conocimiento/genética , Trastornos del Conocimiento/fisiopatología , Estrógenos/metabolismo , Femenino , Humanos , Inteligencia , Memoria , Persona de Mediana Edad , Destreza Motora , Pruebas Neuropsicológicas , Síndrome de Turner/psicología
7.
J Clin Endocrinol Metab ; 86(12): 5674-80, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11739418

RESUMEN

Leri-Weill dyschondrosteosis (LWD) (MIM 127300) is a dominantly inherited skeletal dysplasia characterized phenotypically by Madelung wrist deformity, mesomelia, and short stature. LWD can now be defined genetically by haploinsufficiency of the SHOX (short stature homeobox-containing) gene. We have studied 21 LWD families (43 affected LWD subjects, including 32 females and 11 males, ages 3-56 yr) with confirmed SHOX abnormalities. We investigated the relationship between SHOX mutations, height deficit, and Madelung deformity to determine the contribution of SHOX haploinsufficiency to the LWD and Turner syndrome (TS) phenotypes. Also, we examined the effects of age, gender, and female puberty (estrogen) on the LWD phenotype. SHOX deletions were present in affected individuals from 17 families (81%), and point mutations were detected in 4 families (19%). In the LWD subjects, height deficits ranged from -4.6 to +0.6 SD (mean +/- SD = -2.2 +/- 1.0). There were no statistically significant effects of age, gender, pubertal status, or parental origin of SHOX mutations on height z-score. The height deficit in LWD is approximately two thirds that of TS. Madelung deformity was present in 74% of LWD children and adults and was more frequent and severe in females than males. The prevalence of the Madelung deformity was higher in the LWD vs. a TS population. The prevalence of increased carrying angle, high arched palate, and scoliosis was similar in the two populations. In conclusion, SHOX deletions or mutations accounted for all of our LWD cases. SHOX haploinsufficiency accounts for most, but not all, of the TS height deficit. The LWD phenotype shows some gender- and age-related differences.


Asunto(s)
Proteínas de Homeodominio/genética , Osteocondrodisplasias/genética , Adolescente , Adulto , Estatura , Niño , Preescolar , Femenino , Eliminación de Gen , Humanos , Masculino , Persona de Mediana Edad , Osteocondrodisplasias/complicaciones , Osteocondrodisplasias/patología , Hueso Paladar/anomalías , Fenotipo , Mutación Puntual/genética , Escoliosis/etiología , Proteína de la Caja Homeótica de Baja Estatura , Síndrome de Turner/complicaciones , Síndrome de Turner/genética , Síndrome de Turner/patología , Muñeca/anomalías
8.
Am J Med Genet ; 102(4): 353-8, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11503163

RESUMEN

We report on a man with neurofibromatosis type 1 (NF1) and Leri-Weill dyschondrosteosis (LWD). His father had NF1. His mother had LWD plus additional findings of Turner syndrome (TS): high arched palate, bicuspid aortic valve, aortic stenosis, and premature ovarian failure. The proband's karyotype was 46,X,dic(X;Y)(p22.3;p11.32). Despite having almost the same genetic constitution as 47,XXY Klinefelter syndrome, he was normally virilized, although slight elevation of serum gonadotropins indicated gonadal dysfunction. His mother's karyotype was mosaic 45,X[17 cells]/46,X,dic(X;Y)(p22.3;p11.32)[3 cells].ish dic(X;Y)(DXZ1 +,DYZ1 + ). The dic(X;Y) chromosome was also positive for Y markers PABY, SRY, and DYZ5, but negative for SHOX. The dic(X;Y) chromosome was also positive for X markers DXZ1 and a sequence < 300 kb from PABX, suggesting that the deletion encompassed only pseudoautosomal sequences. Replication studies indicated that the normal X and the dic(X;Y) were randomly inactivated in the proband's lymphocytes. LWD in the proband and his mother was explained by SHOX haploinsufficiency. The mother's female phenotype was most likely due to 45,X mosaicism. This family segregating Mendelian and chromosomal disorders illustrates extreme sex chromosome variation compatible with normal male and female sexual differentiation. The case also highlights the importance of karyotyping for differentiating LWD and TS, especially in patients with findings such as premature ovarian failure or aortic abnormalities not associated with isolated SHOX haploinsufficiency.


Asunto(s)
Proteínas de Unión al ADN/genética , Neurofibromatosis 1/genética , Proteínas Nucleares , Osteocondrodisplasias/genética , Factores de Transcripción , Adulto , Bandeo Cromosómico , Femenino , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Neurofibromatosis 1/diagnóstico , Osteocondrodisplasias/diagnóstico , Linaje , Procesos de Determinación del Sexo , Proteína de la Región Y Determinante del Sexo
9.
JAMA ; 281(12): 1112-20, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10188663

RESUMEN

OBJECTIVE: To establish, in a single resource, up-to-date recommendations for primary care physicians regarding prevention strategies for a first stroke. PARTICIPANTS: Members of the National Stroke Association's (NSA's) Stroke Prevention Advisory Board and Cedars-Sinai Health System Department of Health Services Research convened on April 9, 1998, in an open meeting. The conference attendees, selected to participate by the NSA, were recognized experts in neurology (9), cardiology (2), family practice (1), nursing (1), physician assistant practices (1), and health services research (2). EVIDENCE: A literature review was carried out by the Department of Health Services Research, Cedars-Sinai Health System, Los Angeles, Calif, using the MEDLINE database search for 1990 through April 1998 and updated in November 1998. English-language guidelines, statements, meta-analyses, and overviews on prevention of a first stroke were reviewed. CONSENSUS PROCESS: At the meeting, members of the advisory board identified 6 important stroke risk factors (hypertension, myocardial infarction [MI], atrial fibrillation, diabetes mellitus, blood lipids, asymptomatic carotid artery stenosis), and 4 lifestyle factors (cigarette smoking, alcohol use, physical activity, diet). CONCLUSIONS: Several interventions that modify well-documented and treatable cardiovascular and cerebrovascular risk factors can reduce the risk of a first stroke. Good evidence for direct stroke reduction exists for hypertension treatment; using warfarin for patients after MI who have atrial fibrillation, decreased left ventricular ejection fraction, or left ventricular thrombus; using 3-hydroxy-3 methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors for patients after MI; using warfarin for patients with atrial fibrillation and specific risk factors; and performing carotid endarterectomy for patients with stenosis of at least 60%. Observational studies support the role of modifying lifestyle-related risk factors (eg, smoking, alcohol use, physical activity, diet) in stroke prevention. Measures to help patients improve adherence are an important component of a stroke prevention plan.


Asunto(s)
Trastornos Cerebrovasculares/prevención & control , Guías de Práctica Clínica como Asunto , Consumo de Bebidas Alcohólicas , Fibrilación Atrial/prevención & control , Enfermedades de las Arterias Carótidas/prevención & control , Trastornos Cerebrovasculares/epidemiología , Diabetes Mellitus/prevención & control , Ejercicio Físico , Humanos , Hipertensión/prevención & control , Estilo de Vida , Infarto del Miocardio/prevención & control , Factores de Riesgo
10.
J Pediatr ; 131(5): 666-70, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9403643

RESUMEN

OBJECTIVES: The identification of constitutional cytogenetic abnormalities in patients with cancer may indicate loci of genes, abnormalities of which are responsible for tumor development or progression. This study was undertaken to determine whether girls with Turner's syndrome (TS) (partial or complete deletion of an X chromosome, short stature, gonadal dysgenesis) are at increased risk of neural crest-derived tumors. STUDY DESIGN: Medical records of 394 patients with TS who were followed up at Thomas Jefferson Hospital and Children's Hospital of Pittsburgh were reviewed for documentation of TS phenotype, constitutional cytogenetics, and history of neuroblastoma or related tumors. Informative cases were reviewed for tumor pathology, primary site, disease stage, associated symptoms, treatment, and outcome. RESULTS: Three patients were found to have neuroblastoma. A fourth child who died of neurofibrosarcoma was found to have extensive areas of ganglioneuroma, the benign counterpart of neuroblastoma, at autopsy. An additional four girls with TS and neuroblastoma were identified in the literature, as were two more patients with ganglioneuroma. These 10 patients ranged in age from 1 week to 16 10/12 years (median age, 3 years), and all but two of the children had localized lesions. Two of the seven children with neuroblastoma had courses complicated by opsoclonus-myoclonus, a syndrome found in fewer than 5% of all patients with neuroblastoma. CONCLUSIONS: These data strongly suggest that girls with TS are predisposed to the development of neuroblastoma and related tumors. Because these tumors are often of limited stage and may be underdiagnosed, screening of urine of patients with TS for elevated catecholamine metabolite levels may strengthen this association.


Asunto(s)
Neuroblastoma/complicaciones , Síndrome de Turner/complicaciones , Adolescente , Niño , Preescolar , Aberraciones Cromosómicas/genética , Deleción Cromosómica , Trastornos de los Cromosomas , Femenino , Estudios de Seguimiento , Ligamiento Genético/genética , Humanos , Lactante , Recién Nacido , Cariotipificación , Neuroblastoma/genética , Síndrome de Turner/genética , Cromosoma X/genética
11.
J Immunol ; 155(4): 1972-80, 1995 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-7636248

RESUMEN

Expression of the IL-2R alpha gene is regulated by members of the c-Rel/NF-kappa B family of transcription factors binding to the kappa B site in the promoter. Previous work has not defined the role of individual members of the c-Rel family in the activation of the IL-2R alpha gene. Using the COS cell system, we were able to reconstitute the regulation of the IL-2R alpha promoter by expressing cloned Rel family members with serum response factor (SRF). We found that c-rel alone activated the IL-2R alpha promoter only weakly but worked with the p50 subunit of NF-kappa B (NFKB1) to give a higher level of expression. We showed that c-rel heterodimerizes with p50 and the amount of this heterodimer correlated with the level of IL-2R alpha gene expression. Our results provide evidence that c-rel/p50 heterodimers activate gene expression in the context of a cellular promoter. We show that c-rel or p65 can cooperate with SRF in the activation of this promoter and the transactivation by c-rel with SRF was enhanced by p50. Synergistic activation required both kappa B and CArG sites, and binding studies show that these adjacent sites can be occupied simultaneously. The transactivation observed with cloned transcription factors mimics the physiologic induction of the IL-2R alpha gene since multiple sequence elements cooperate to give gene activation. The data support the model that c-rel/p50 or p65 can cooperate with SRF to specifically target the expression of the IL-2R alpha gene in activated T cells.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Regulación de la Expresión Génica , Proteínas Nucleares/fisiología , Receptores de Interleucina-2/genética , Secuencia de Aminoácidos , Secuencia de Bases , Línea Celular , Datos de Secuencia Molecular , FN-kappa B/fisiología , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas/química , Proteínas Proto-Oncogénicas/fisiología , Proteínas Proto-Oncogénicas c-rel , Factor de Respuesta Sérica , Activación Transcripcional
12.
J Clin Endocrinol Metab ; 80(4): 1357-60, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7714111

RESUMEN

GH every 20 min for 24 h, insulin-like growth factor I (IGF-I), IGF-binding protein 3, and estradiol (E2) were measured in a 7.3-yr-old girl with precocious puberty due to McCune-Albright syndrome (MAS) who developed stigmata of early acromegaly and in 9 other MAS patients who had no signs of acromegaly. To determine whether the MAS patients had subtle abnormalities in GH secretion, a computerized pulse analysis program was used to compare the MAS data with those from 27 control girls with central precocious puberty who had a similar rate of bone age advance, E2, and body mass index. We found no differences in mean GH, GH pulse frequency, pulse height, or pulse area between MAS patients and controls except in patient 1, who had an elevated mean +/- SD GH compared with controls (15.4 +/- 2 vs. 4.8 +/- 2.3 micrograms/L; P < 0.01) and an elevated IGF-I (908 micrograms/L) and IGF-binding protein 3 (5.6 mg/L). None of the GH parameters correlated with body mass index, age, bone age, or E2 levels in either group. The serum GH in patient 1 fell to near-undetectable levels from 60-180 min after a 100-micrograms sc dose of long-acting somatostatin, confirming that this form of therapy can be effective in cases of GH hypersecretion due to MAS.


Asunto(s)
Displasia Fibrosa Poliostótica/tratamiento farmacológico , Displasia Fibrosa Poliostótica/metabolismo , Hormona del Crecimiento/metabolismo , Somatostatina/análogos & derivados , Niño , Preescolar , Femenino , Hormona del Crecimiento/sangre , Humanos , Pubertad Precoz/sangre , Valores de Referencia
13.
Acta Paediatr Jpn ; 34(2): 195-202; discussion 202-5, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1621525

RESUMEN

Girls with Turner's syndrome are born short, grow slowly, and usually fail to enter puberty spontaneously and to undergo a pubertal growth spurt. The goal of estrogen therapy is to correct estrogen deficiency in a manner that optimizes height potential, permits attainment of normal bone mass, and provides appropriate feminization with minimal risk of adverse effects. The issues to be resolved include the age at which treatment should be begun, the preparation, route of administration, and dosage to be given, the effect on concurrent growth hormone administration, the rate of dose increase during treatment, the timing and nature of progestin administration, and the total duration of treatment. The available data suggest that treatment should be initiated between the ages of 12 and 14 years. The dose-response relationship between growth rate and estrogen dose is biphasic. Optimal growth stimulation for ethinyl estradiol occurs at approximately 100 ng/kg body weight per day, which is below the dose that produces full feminization. Although suboptimal doses of estrogen and growth hormone appear to have additive effects, estrogen causes only a minor increase in the short-term growth response to an optimal dose of growth hormone. The long-term effects of estrogen combined with growth hormone are unknown. In the absence of data concerning the outcome of different dose schedules, we treated for 2 years at 100 ng/kg/day of ethinyl estradiol, then double the dose annually until menstruation, at which time cyclic monthly progestin therapy is added (medroxyprogesterone acetate 10 mg daily from days 16 to 25). The importance of estrogen in maintaining normal bone mass suggests that treatment should be lifelong. Current research in our clinic is assessing the long-term effect on adult height of ultra-low-dose treatment (25 to 50 ng/kg/day of ethinyl estradiol) during the childhood years (ages 5 to 11), alone or in conjunction with supplemental growth hormone.


Asunto(s)
Hormona Liberadora de Hormona del Crecimiento/uso terapéutico , Síndrome de Turner/tratamiento farmacológico , Adolescente , Estatura , Niño , Estrógenos/administración & dosificación , Estrógenos/uso terapéutico , Etinilestradiol/administración & dosificación , Etinilestradiol/uso terapéutico , Femenino , Trastornos del Crecimiento/tratamiento farmacológico , Trastornos del Crecimiento/genética , Humanos , Masculino , Progestinas/uso terapéutico , Síndrome de Turner/etiología , Síndrome de Turner/fisiopatología
14.
J Clin Endocrinol Metab ; 72(5): 1108-12, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-2022710

RESUMEN

Solitary autonomous thyroid tumors are an unusual cause of hyperthyroidism, particularly in childhood. We describe the youngest individual so far reported with this condition, a 22 month child with a large hyperfunctioning thyroid nodule who became overtly hyperthyroid after iodinated contrast administration. The histology of the nodule was compatible with follicular cell hyperplasia. These tumors are often called toxic adenomas, although there is no solid evidence that they are true neoplasms. We examined the clonal composition of the child's thyroid tumor by X-chromosome inactivation analysis, taking advantage of a polymorphism in the X-chromosome gene phosphoglycerate kinase. The tumor consisted of an even mixture of cells containing activated paternal and maternal PGK alleles, indicating that the tumor was polyclonal. Furthermore, the nodule had no structural rearrangements or activating point mutations of ras oncogenes, which are found in up to 50% of solitary monoclonal follicular adenomas. Solitary hot nodules may at least in some cases be secondary to hyperplasia, and not to clonal expansion of an abnormal, mutated cell. This may also explain the relatively low frequency of malignant transformation observed in hyperfunctioning thyroid tumors.


Asunto(s)
Adenoma/complicaciones , Hipertiroidismo/etiología , Neoplasias de la Tiroides/complicaciones , Adenoma/genética , Adenoma/patología , Transformación Celular Neoplásica/patología , ADN de Neoplasias/análisis , ADN de Neoplasias/genética , Electroforesis en Gel de Poliacrilamida , Femenino , Genes ras/genética , Ligamiento Genético/genética , Humanos , Hiperplasia/patología , Hipertiroidismo/genética , Hipertiroidismo/patología , Lactante , Sondas de Oligonucleótidos , Fosfoglicerato Quinasa/genética , Polimorfismo Genético/genética , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Cromosoma X
15.
Horm Res ; 29(1): 23-6, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3397039

RESUMEN

Growth hormone secretory dynamics and plasma somatomedin C concentrations were assessed in four prepubertal patients with defects in the low-density lipoprotein (LDL) receptor pathway before and after 2 months of treatment with mevinolin, an HMG-CoA reductase inhibitor that reduces intracellular cholesterol. Pre- and posttreatment mean 24-hour growth hormone levels and pulse amplitude were similar and tended to be higher than in age-matched prepubertal controls. Pre- and posttreatment somatomedin C levels were also similar and lower than in age-matched prepubertal controls. All patients responded to growth hormone provocative testing with a peak response of greater than 7 ng/ml, independent of treatment status. Growth velocity was not significantly altered in any patient following 2 months of treatment with mevinolin, and was within the normal range for age. Thus, children with defects in the LDL receptor pathway express abnormalities in growth hormone secretion and somatomedin C generation comparable to those seen in other chronic diseases. Treatment with mevinolin has no apparent effect on these biochemical abnormalities, suggesting that it may not have long-term effects on growth. Regardless of mevinolin therapy, children with defects in the LDL receptor pathway may manifest a degree of growth retardation and, hence, growth rate and skeletal maturation should be closely monitored.


Asunto(s)
Hormona del Crecimiento/metabolismo , Hiperlipoproteinemia Tipo II/metabolismo , Factor I del Crecimiento Similar a la Insulina/análisis , Somatomedinas/análisis , Niño , Preescolar , Femenino , Hormona del Crecimiento/sangre , Humanos , Hiperlipoproteinemia Tipo II/sangre , Lípidos/sangre , Lipoproteínas/sangre , Masculino , Receptores de LDL/fisiología
16.
J Clin Endocrinol Metab ; 63(1): 174-9, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3086356

RESUMEN

The normal ranges for GH responses to GH-releasing hormone (GHRH) have previously been defined for adult men and women. To determine whether the GHRH responses of normal children differ from those of adults and whether children with GH deficiency (GHD) and children who are growing below the first percentile but are otherwise normal (ISS) have GH responses comparable to those of normal children, we studied 90 normal children, 46 girls and 44 boys, with heights between the 10th and 95th percentiles for age, at different pubertal stages. Their responses were compared to those of 24 children with ISS and 32 children with GHD and to values previously measured in young adult men and women. Girls were grouped by Tanner breast stages and boys by testicular volumes. Plasma somatomedin-C, estradiol or testosterone, and bone age were measured in all children. All received a 1 microgram/kg iv bolus dose of GHRH-(1-44)NH2, and GH responses were measured during a 2-h sampling period. Incremental serum GH responses in girls did not change throughout pubertal development and were similar to those of adult women. The responses in boys at midpuberty were somewhat lower (P less than 0.05) than those in either prepubertal boys or adult men. ISS children had mean GH responses [23 +/- 4 (+/- SE) ng/ml] similar to those of normal children. GHD children had significantly lower mean GH responses (11 +/- 3.7 ng/ml) than normal prepubertal children (35 +/- 4.0 ng/ml; P less than 0.01), but the responses of 17 of the 32 GHD children overlapped with the normal range. GH responses to GHRH were not correlated with bone age, weight, height, SmC levels, or estradiol or testosterone concentrations. These results indicate that GH responses to GHRH testing are relatively constant throughout puberty and young adulthood, that ISS children respond normally to GHRH, and that the GHRH test is not a reliable discriminator between individual normal and GHD children.


Asunto(s)
Trastornos del Crecimiento/metabolismo , Hormona Liberadora de Hormona del Crecimiento , Hormona del Crecimiento/metabolismo , Pubertad , Adolescente , Adulto , Niño , Preescolar , Estradiol/sangre , Femenino , Hormona del Crecimiento/sangre , Hormona del Crecimiento/deficiencia , Humanos , Factor I del Crecimiento Similar a la Insulina/sangre , Masculino , Testosterona/sangre
19.
J Clin Endocrinol Metab ; 61(5): 896-8, 1985 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-4044777

RESUMEN

We previously described a biphasic dose-response curve for ethinyl estradiol on short term growth in patients with Turner's syndrome. To investigate whether there is a similar phenomenon in boys, we measured the 3-week ulnar growth velocity (TUG) after administration of different doses of estradiol to five prepubertal or early pubertal boys. Basal TUG was determined initially. Subsequently, the boys received a 4-day iv infusion of estradiol at each of three doses (4, 20, and 90 micrograms/day) given double blind in a randomized sequence. TUG was determined before and after each infusion and was allowed to return to baseline before giving the second and third infusions. Mean TUG increased from 0.45 +/- 0.11 (+/- SEM) to 1.38 +/- 0.51 mm/3 weeks after the 4 micrograms/day infusion (P less than 0.05), from 0.49 +/- 0.11 to 1.0 +/- 0.4 mm/3 weeks after the 20 micrograms/day infusion (P = NS), and from 0.46 +/- 0.1 to 0.84 +/- 0.12 mm/3 weeks after the 90 micrograms/day infusion (P = NS). The mean serum estradiol level was 10 +/- 2.3 pg/ml during the 4 micrograms/day infusion, 16 +/- 2.3 pg/ml during the 20 micrograms/day infusion, and 96 +/- 12 pg/ml during the 90 micrograms/day infusion. Mean serum somatomedin-C levels were significantly higher only after the 20 and 90 micrograms/day estradiol infusions. We conclude that low dose estrogen can stimulate ulnar growth in boys and may play a role in the male pubertal growth spurt.


Asunto(s)
Estradiol/administración & dosificación , Cúbito/crecimiento & desarrollo , Adolescente , Método Doble Ciego , Esquema de Medicación , Estradiol/sangre , Estradiol/farmacología , Humanos , Infusiones Parenterales , Factor I del Crecimiento Similar a la Insulina/sangre , Masculino , Cúbito/efectos de los fármacos
20.
J Clin Endocrinol Metab ; 59(4): 801-5, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6434582

RESUMEN

Six girls with McCune-Albright syndrome were treated for at least 2 months with the long-acting LHRH agonist D-Trp6-Pro9-NEt-LHRH, which previously was found to be an effective treatment for true precocious puberty. Nocturnal and LHRH-stimulated serum gonadotropin levels and plasma estradiol levels were measured before treatment and after 2-3 months of treatment. Five of the six girls had no decrease in serum gonadotropin or plasma estradiol levels during therapy, and their pubertal signs were unaffected by treatment. All five of these girls had serum gonadotropin levels that were within or below the normal prepubertal range. The sixth girl, who had gonadotropin levels in the normal pubertal range before treatment, had decreased serum gonadotropin and plasma estradiol levels during 1 yr of LHRH analog therapy. This was associated with cessation of menses and regression of secondary sexual changes. The failure of LHRH analog to modify the course of precocious puberty in the five patients with prepubertal serum gonadotropin concentrations is further evidence that the mechanism of precocious puberty in most girls with McCune-Albright syndrome differs from that in patients with true precocious puberty.


Asunto(s)
Estradiol/sangre , Displasia Fibrosa Ósea/tratamiento farmacológico , Displasia Fibrosa Poliostótica/tratamiento farmacológico , Hormona Liberadora de Gonadotropina/análogos & derivados , Gonadotropinas/sangre , Pubertad Precoz/tratamiento farmacológico , Pamoato de Triptorelina/análogos & derivados , Niño , Preescolar , Preparaciones de Acción Retardada , Femenino , Displasia Fibrosa Poliostótica/sangre , Displasia Fibrosa Poliostótica/complicaciones , Hormona Folículo Estimulante/sangre , Hormona Liberadora de Gonadotropina/uso terapéutico , Humanos , Lactante , Hormona Luteinizante/sangre , Pubertad Precoz/sangre , Pubertad Precoz/etiología , Caracteres Sexuales
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