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1.
Osteoporos Int ; 26(5): 1515-24, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25600474

RESUMEN

UNLABELLED: Anti-osteoporosis medication (AOM) use in patients exposed to glucocorticoids is thought to reduce fractures. We found post-menopausal women using glucocorticoids for at least 90 days who also used an AOM within 90 days had 48 % fewer fractures by 1 year and 32 % fewer fractures by 3 years compared to non-AOM users. INTRODUCTION: The purpose of this study is to explore the effectiveness of adherence to quality measures by estimating the effect of anti-osteoporosis medication (AOM) initiation within 90 days after chronic (≥90 days) glucocorticoid (GC) therapy on osteoporotic fracture. METHODS: A new-user cohort was assembled using the MarketScan databases between 2000 and 2012. Included patients were female, age ≥50 at GC initiation, had a first GC fill daily dose ≥10 mg and persisted for at least 90 days. During a 365-day baseline period, patients were excluded for prior GC or AOM (bisphosphonate, denosumab, teriparatide) use, fracture, or cancer diagnosis. Initiators of an AOM in the 14 days pre- or 90 days post-GC fill were characterized as AOM users; those without, AOM non-users. Follow-up began 91 days after GC fill with patients followed until fracture, loss of continuous enrollment, initiation of AOM by AOM non-users, or end of study period. A propensity score was estimated for AOM receipt using all measured covariates and converted to a stabilized inverse probability of treatment weights (IPTW). Weighted hazard ratios (HR) and associated 95% confidence intervals (95% CI) were estimated using weighted Cox proportional hazard models. RESULTS: Of the 7885 women eligible for the study, 12.1% were AOM users. AOM use was associated with lower fracture incidence: weighted HR of 0.52 (95% CI 0.29, 0.94) at 1 year and weighted HR of 0.68 (95% CI 0.47, 0.99) at 3 years. CONCLUSIONS: AOM initiation within 90 days of chronic GC use was associated with a fracture reduction of 48% at 1 year and 32% at 3 years.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Glucocorticoides/efectos adversos , Osteoporosis Posmenopáusica/tratamiento farmacológico , Fracturas Osteoporóticas/prevención & control , Administración Oral , Anciano , Anciano de 80 o más Años , Esquema de Medicación , Femenino , Estudios de Seguimiento , Glucocorticoides/administración & dosificación , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/inducido químicamente , Osteoporosis Posmenopáusica/complicaciones , Fracturas Osteoporóticas/etiología , Estudios Retrospectivos
2.
Clin Genet ; 82(6): 505-13, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22288726

RESUMEN

Familial recurrence risks are poorly understood in cases of de novo mutations. In the event of parental germ line mosaicism, recurrence risks can be higher than generally appreciated, with implications for genetic counseling and clinical practice. In the course of treating a female with pubertal delay and hypergonadotropic hypogonadism, we identified a new missense mutation in the SRY gene, leading to somatic feminization of this karyotypically normal XY individual. We tested a younger sister despite a normal onset of puberty, who also possessed an XY karyotype and the same SRY mutation. Imaging studies in the sister revealed an ovarian tumor, which was removed. DNA from the father's blood possessed the wild type SRY sequence, and paternity testing was consistent with the given family structure. A brother was 46, XY with a wild type SRY sequence strongly suggesting paternal Y-chromosome germline mosaicism for the mutation. In disorders of sexual development (DSDs), early diagnosis is critical for optimal psychological development of the affected patients. In this case, preventive karyotypic screening allowed early diagnosis of a gonadal tumor in the sibling prior to the age of normal puberty. Our results suggest that cytological or molecular diagnosis should be applied for siblings of an affected DSD individual.


Asunto(s)
Genes sry/genética , Células Germinativas/metabolismo , Disgenesia Gonadal 46 XY/genética , Mosaicismo , Mutación Missense/genética , Adolescente , Secuencia de Aminoácidos , Ensayo de Cambio de Movilidad Electroforética , Femenino , Disgenesia Gonadal 46 XY/patología , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Resonancia Magnética Nuclear Biomolecular , Oligonucleótidos/genética , Linaje , Alineación de Secuencia
3.
Genes Immun ; 11(7): 590-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20535137

RESUMEN

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare autoimmune disease causing a wide spectrum of autoimmune dysfunction potentially including diabetes of an autoimmune etiology. We have previously described a pair of discordant APECED siblings and pointed to a possible role of 5'insulin variable number of tandem repeats (VNTR) locus IDDM2 in the appearance of diabetes within this disease. In vitro studies have previously suggested that class I VNTR alleles were associated with decreased fetal thymic insulin expression. We genotyped the 5'INS VNTR locus and several flanking 11p15.5 markers in 50 Finnish APECED subjects and explored the possible contribution of IDDM2 in the development of diabetes. The shorter 5'INS VNTR class I alleles (<35 repeats) were more prevalent in the diabetic Finnish APECED subjects than in non-diabetic APECED subjects. Logistic regression analysis revealed that having 1 short (<35) VNTR allele did not increase the risk of developing diabetes (95% CI 0.6-27.0), whereas having 2 short alleles conferred a 43.5-fold increased risk (95% CI 3.0-634.6). We conclude that short 5'INS VNTR class I alleles play a role in susceptibility to autoimmune diabetes in the context of APECED.


Asunto(s)
Diabetes Mellitus Tipo 1/genética , Insulina/genética , Repeticiones de Minisatélite/genética , Poliendocrinopatías Autoinmunes/genética , Adulto , Alelos , Estudios de Cohortes , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 2/genética , Susceptibilidad a Enfermedades , Femenino , Genotipo , Humanos , Insulina/biosíntesis , Insulina/inmunología , Masculino , Estudios Retrospectivos , Riesgo , Población Blanca/genética
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.
Med Hypotheses ; 66(1): 38-44, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16198060

RESUMEN

Too small size at birth (due to poor fetal growth and/or preterm delivery) has been associated with substantially elevated risks of the metabolic syndrome (dislipidemia, insulin resistance, hypertension), type 2 diabetes and cardiovascular disease in adulthood. The mechanisms of such "fetal origins" or "programming" of disease phenomenon remain unresolved. Too large size at birth seems also associated with an increased risk. Many known or suspected causes of or conditions associated with adverse (poor or excessive) fetal growth or preterm birth have been associated with oxidative stress. Plausibly, oxidative stress may be a common link underlying the superficial "programming" associations between adverse fetal growth or preterm birth and elevated risks of certain chronic diseases. The mechanisms of oxidative stress programming may be through directly modulating gene expression or indirectly through the effects of certain oxidized molecules. Experimental investigations have well demonstrated the role of redox balance in modulating gene expression, and recent studies indicate that both the insulin functional axis and blood pressure could be sensitive targets to oxidative stress programming. Adverse programming may occur without affecting fetal growth, but more frequently among low birth weight infants merely because they more frequently experienced known or unknown conditions with oxidative insults. As oxidative stress levels are easily modifiable during pregnancy and early postnatal periods (which are plausible critical windows), the hypothesis, if proved valid, will suggest new measures that could be very helpful on fighting the increasing epidemic of the metabolic syndrome, type 2 diabetes and cardiovascular disease. Currently, there are several ongoing large randomized trials of antioxidant supplementation to counter oxidative stress during pregnancy for the prevention of preeclampsia. It would be invaluable if long-term follow-ups of infants born to women in such trials could be realized to test the oxidative stress programming hypothesis in such experimental trial settings.


Asunto(s)
Peso al Nacer/fisiología , Desarrollo Fetal/fisiología , Trastornos Nutricionales en el Feto/fisiopatología , Síndrome Metabólico/etiología , Estrés Oxidativo/fisiología , Efectos Tardíos de la Exposición Prenatal , Femenino , Humanos , Embarazo
6.
Biochim Biophys Acta ; 1439(1): 77-88, 1999 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-10395967

RESUMEN

Phosphatidylcholine (PtdCho) is the most abundant phospholipid in mammalian cell membranes and is essential for cell viability. The levels of this lipid must be tightly controlled to maintain homeostasis. Therefore, changes in the rate of PtdCho synthesis are generally balanced by changes in PtdCho catabolism and vice versa. It is commonly accepted that the rate of PtdCho synthesis is regulated by CTP:phosphocholine cytidylyltransferase (CT). However, it is not certain if PtdCho mass is regulated by specific catabolic enzyme(s). Our goal is to determine if PtdCho homeostasis is regulated by a phospholipase A2 (PLA2). To this end, we have prepared Chinese hamster ovary (CHO) cell lines that overexpress CT. CT activity is 7-10-fold higher in the transfected cells than in parental CHO cells. This increase in CT activity is associated with increases in both PtdCho synthesis and PtdCho catabolism. Glycerophosphocholine is the PtdCho catabolite that accumulates in the transfected cells, which suggests that PtdCho turnover is mediated by a phospholipase A2 (PLA2). Indeed, higher levels of calcium-independent PLA2 activity are measured in the cytosols of the CHO cells that overexpress CT, compared to parental CHO cells. The elevated calcium-independent PLA2 activity is associated with increases in the expression of the 80-kDa calcium-independent PLA2 (iPLA2). Together, these data suggest that the 80-kDa iPLA2 may be modulated in response to changes in PtdCho levels and therefore is involved in the regulation of PtdCho homeostasis in CHO cells.


Asunto(s)
Citidililtransferasa de Colina-Fosfato/metabolismo , Fosfatidilcolinas/metabolismo , Fosfolipasas A/metabolismo , Animales , Células CHO , Supervivencia Celular , Citidililtransferasa de Colina-Fosfato/biosíntesis , Citidililtransferasa de Colina-Fosfato/genética , Cricetinae , Expresión Génica , Glicerilfosforilcolina/metabolismo , Fosfolipasas A2 Grupo VI , Homeostasis , Immunoblotting , Fosfatidilcolinas/biosíntesis , Fosfolipasas A2 , Transfección
7.
Endocrinology ; 134(3): 1382-8, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7509740

RESUMEN

The genetically obese Zucker rat is a widely used model of early-onset obesity. Like obese children, these obese rats are hyperinsulinemic and have low GH secretion. However, data on linear growth and insulin-like growth factor-I (IGF-I) levels in this model are scanty and contradictory. In the present study, we investigated linear growth and its hormonal control in Zucker rats (male and female) from 4-20 weeks of age. In the obese animals, compared to their lean littermates, the naso-anal length was normal or slightly greater, whereas the tails and femurs were shorter. The plasma concentration of IGF-I increased between 4-20 weeks of age, and IGF-I levels were normal or slightly higher in the obese animals. The serum level of IGF-binding protein-3 (IGFBP-3) measured by Western ligand blotting was not significantly different in lean vs. obese rats. To assess the IGF-I response to GH, bovine GH was administered (250 micrograms/100 g BW, ip, daily for 3 days) to 16- to 20-week-old female Zucker rats; plasma IGF-I concentrations increased more in the obese (percent increase over baseline, 347 +/- 44% vs. 194 +/- 31%; P < 0.01). These results show that despite low GH secretion, genetically obese Zucker rats have 1) normal linear (nasoanal) growth, 2) normal or increased circulating levels of IGF-I and IGFBP-3, and 3) increased plasma IGF-I responses to exogenous GH. These results suggest that the GH-independent growth in this model could result from direct effects of hyperinsulinism on circulating IGF-I and IGFBP-3 levels and/or indirect effects through increased GH receptor function.


Asunto(s)
Proteínas Portadoras/sangre , Hormona del Crecimiento/farmacología , Factor I del Crecimiento Similar a la Insulina/análisis , Obesidad/fisiopatología , Ratas Zucker/crecimiento & desarrollo , Animales , Femenino , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina , Masculino , Obesidad/sangre , Ratas , Receptores de Somatotropina/fisiología
8.
Endocrinology ; 141(2): 666-74, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10650948

RESUMEN

During the course of human pregnancy, there is a marked increase in insulin-like growth factor (IGF) binding protein (IGFBP)-3 protease activity in maternal serum that is first evident at 6 weeks of gestation, persists through term, and returns to nonpregnancy levels by day 5 postpartum. This protease activity cleaves IGFBP-3 into smaller fragments that have markedly reduced affinity for the IGFs. To date, the precise identity and cellular origin of the pregnancy-associated serum IGFBP-3 protease have not been established. To investigate whether placental and/or decidual tissues, which uniquely develop during pregnancy, may be sources of the pregnancy-associated serum IGFBP protease, we examined the secretion of IGFBP-3 protease in vitro by isolated human cytotrophoblasts or fibroblasts from second trimester placentae and by in vitro decidualized human endometrial stromal cells. Cytotrophoblasts were either cultured alone, which favors aggregation and fusion, or cocultured with decidualized endometrial stromal cells, which favors differentiation to an invasive phenotype. IGFBP-3 protease activity was detected in trophoblast, but not in placental fibroblast or decidualized endometrial cultures, and was also present in trophoblast-endometrial cocultures. Western ligand blot and Western immunoblot analyses showed that most of the endogenous IGFBP-3 in trophoblast cultures was in the form of low molecular weight fragments with reduced IGF binding affinity. The substrate specificity of the trophoblast-derived protease was identical to that in pregnancy serum, showing activity against IGFBP-2, -3, and -4, but being inactive against IGFBP-1. IGFBP-3 proteolysis by both pregnancy serum and trophoblast conditioned medium showed a major peak of activity at neutral pH. The trophoblast-derived activity caused time-and temperature-dependent proteolysis of IGFBP-3 into fragments of identical size as those produced by pregnancy serum, and also shared its sensitivity to protease inhibitors: highly sensitive to EDTA and o-phenanthroline, partially sensitive to the serine protease inhibitors AEBSF and aprotinin, and insensitive to alpha2-antiplasmin, and to aspartic and cysteine protease inhibitors. IGFBP-3 proteolysis by both pregnancy serum and trophoblast conditioned medium was also insensitive to tissue inhibitor of metalloproteinase-1, precluding the involvement of the matrix metalloproteinases. In contrast, both the pregnancy serum- and trophoblast-derived proteases were preferentially inhibited by a hydroxamic acid derivative with selective activity against the disintegrin-metalloproteinase tumor necrosis factor-alpha converting enzyme. This study shows that placental trophoblasts produce an IGFBP-3 protease with characteristics very similar to the activity found in pregnancy serum and indicates these cells at the maternal-fetal interface are a potential source of the pregnancy-associated serum IGFBP-3 protease. The findings further suggest that the main IGFBP-3 protease activity in both pregnancy serum and trophoblast conditioned medium may correspond to a disintegrin-metalloproteinase type enzyme.


Asunto(s)
Endopeptidasas/biosíntesis , Endopeptidasas/sangre , Embarazo/sangre , Trofoblastos/enzimología , Células Cultivadas , Medios de Cultivo Condicionados , Endopeptidasas/metabolismo , Femenino , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Cinética , Metaloendopeptidasas/biosíntesis , Metaloendopeptidasas/metabolismo , Placenta/citología , Inhibidores de Proteasas/farmacología , Proteínas Recombinantes/metabolismo , Especificidad por Sustrato , Trofoblastos/citología
9.
J Clin Endocrinol Metab ; 81(1): 222-7, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8550756

RESUMEN

We have previously reported that despite neonatal screening, children with severe congenital hypothyroidism treated at 5 weeks of age with 6 micrograms/kg.day levothyroxine have clinically significant intellectual impairment, whereas those with the moderate form of the disease are indistinguishable from controls. The developmental outcome of children with severe congenital hypothyroidism treated earlier with higher initial doses of levothyroxine remained to be determined. In the present study, 45 infants with permanent congenital hypothyroidism detected by neonatal screening are described. For the group, the median age at starting treatment was 14 days, and the median initial dose of levothyroxine was 11.6 micrograms/kg.day. Based on the area of their knee epiphyses at diagnosis, the patients were divided into 2 subgroups: severe (< 0.05 cm2; n = 10) and moderate (> or = 0.05 cm2; n = 35). The psychomotor development of 8 patients in each subgroup, matched for the socioeducational level of their families, was assessed at 18 months. Mean plasma free T4 levels were supraphysiological during the first few months of life, but mean plasma T3 levels remained within the normal range, and there were no signs or symptoms of hyperthyroidism. The mean plasma TSH concentration was less than 4.5 mIU/L 4 weeks after starting treatment. Bone maturation remained delayed at 12 months in the severe cases and was not unduly advanced in the moderate cases. The mean (+/- SD) developmental quotients at 18 months were similar in severe and moderate cases (107 +/- 10 and 110 +/- 5, respectively). We conclude that with earlier treatment and a higher initial dose of levothyroxine, the early developmental outcome of infants with severe congenital hypothyroidism is now indistinguishable from that of infants with the moderate form of the disease who were used as controls.


Asunto(s)
Hipotiroidismo Congénito , Tiroxina/uso terapéutico , Desarrollo Infantil , Humanos , Hipotiroidismo/tratamiento farmacológico , Hipotiroidismo/fisiopatología , Lactante , Recién Nacido , Desempeño Psicomotor , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangre
10.
J Clin Endocrinol Metab ; 79(6): 1747-51, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7527410

RESUMEN

Insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3) is the principal carrier protein of IGF-I in the circulation. IGF-I has been postulated to play a role in the genesis and maintenance of the polycystic ovary syndrome. Regardless of the exact mechanism of action of IGF-I on ovarian steroidogenesis, alterations in the level of IGFBP-3 may play a significant role in regulating the concentration of IGF-I in hyperandrogenism. We have postulated that androgens reduce the circulating IGFBP-3 concentration through a mechanism similar to its suppression of the hepatic production of sex hormone-binding globulin (SHBG), thereby increasing bioavailable IGF-I and amplifying its impact on ovarian steroidogenesis. To test this hypothesis, we studied seven oophorectomized women (aged 39-51 yr; body mass, 20.9-35.8 kg/m2) during 3 weeks of testosterone (T) propionate administration (20 mg, three times weekly). All subjects were receiving 0.625 or 1.25 mg conjugated estrogens/day. Blood was sampled before (week 0), during (weeks 1-3), and after (week 4) T administration. Serum was assayed for total T, GH, and SHBG, and plasma was assessed for IGF-I, insulin (INS), and IGFBP-3. IGFBP-3 was measured by both RIA and Western ligand blotting; (expressed as a percentage of the control value). Circulating T increased from 1.51 +/- 1.06 to 30.8 +/- 13.8 mmol/L by week 2 (P < 0.001). During T administration, IGF-I increased (from 55 +/- 23 ng/mL at week 0 to 124 +/- 37 ng/mL at week 4; P < 0.05); INS did not change, with the exception of a higher fasting level 1 week after discontinuing therapy, and GH decreased (from 1.7 +/- 2.3 micrograms/L at week 0 to 0.4 +/- 0.4 microgram/L at week 4; P < 0.03), as did the circulating SHBG concentration (397 +/- 205 to 273 +/- 93 nmol/L by week 2; P < 0.01). IGFBP-3 levels determined by Western ligand blot were higher during the second and third weeks of T administration (265 +/- 28% and 218 +/- 43% of control values, respectively; P < 0.05) compared to that at week 0 (165 +/- 44% of control values). However, there was no difference in the circulating concentration of IGFBP-3, determined by RIA, at weeks 0, 1, 3, and 4 (3.59 +/- 0.35, 4.00 +/- 0.79, 3.48 +/- 0.56, and 3.65 +/- 0.52 microgram/mL, respectively).(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Proteínas Portadoras/sangre , Ovariectomía , Testosterona/farmacología , Adulto , Western Blotting , Femenino , Hormona del Crecimiento/sangre , Humanos , Insulina/sangre , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina , Factor I del Crecimiento Similar a la Insulina/metabolismo , Persona de Mediana Edad , Radioinmunoensayo , Globulina de Unión a Hormona Sexual/metabolismo , Testosterona/administración & dosificación , Testosterona/sangre
11.
Am J Med ; 102(1A): 35S-39S, 1997 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-9217558

RESUMEN

Osteoporosis is a public health scourge that is usually eminently preventable. Some risk factors, such as low calcium intake, vitamin D deficiency, and physical inactivity, are amenable to early interventions that will help maximize peak bone density. Other risk factors subject to modification are cigarette smoking and excessive consumption of protein, caffeine, and alcohol. Hip fractures are the most serious outcome of osteoporosis, with enormous personal and public health consequences. The ongoing Study of Osteoporotic Fractures has identified additional independent predictors of hip fracture risk, including maternal hip fracture, absence of significant weight gain since age 25, height, hyperthyroidism, use of long-acting benzodiazepines or anticonvulsants, spending < 4 hours a day on one's feet, inability to rise from a chair without using one's arms, poor visual depth perception and contrast sensitivity, and tachycardia. In an individual perimenopausal woman, the risk of osteoporotic fracture and the urgency of estrogen replacement therapy can be best estimated on the basis of bone mineral density, as measured by dual-energy x-ray absorptiometry, coupled with the presence or absence of existing fractures and clinical risk factors evident from the history and physical examination. Estrogen, calcitonin, and bisphosphonates have all been proved effective in retarding postmenopausal bone loss and therefore reducing the risk of fracture. The use of sodium fluoride is more controversial, although a recent study has suggested a possible role for slow-release fluoride combined with high-dose calcium supplementation.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Osteoporosis/diagnóstico , Osteoporosis/terapia , Calcitonina/uso terapéutico , Difosfonatos/uso terapéutico , Quimioterapia Combinada , Terapia de Reemplazo de Estrógeno , Femenino , Fracturas Óseas/etiología , Humanos , Masculino , Osteoporosis/complicaciones , Osteoporosis/fisiopatología , Osteoporosis/prevención & control , Osteoporosis Posmenopáusica , Factores de Riesgo , Fluoruro de Sodio/uso terapéutico
12.
Transplantation ; 58(11): 1186-9, 1994 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-7992360

RESUMEN

In an effort to determine the influence of immunosuppressive therapy and other clinical variables on posttransplant osteopenia, vertebral bone density was measured at least 6 months after transplantation in 65 adult primary renal transplant recipients receiving a variety of immunosuppressive regimens. Fifteen of the 65 patients (23%) had vertebral bone densities below a fracture threshold of 1.0 g hydroxyapatite/cm2. Multivariate analyses indicated that cumulative steroid dose and female gender were the major independent predictors of low vertebral bone density. In women, postmenopausal status also was associated with osteopenia. There was no correlation between cumulative cyclosporine dose and bone density. Results of this study indicate that posttransplant osteopenia is common in renal transplant recipients, including those treated with CsA. Although CsA has allowed the use of lower cumulative doses of steroids, concomitant steroid therapy remains the preeminent factor accounting for loss of bone density.


Asunto(s)
Densidad Ósea , Trasplante de Riñón , Adulto , Anciano , Enfermedades Óseas Metabólicas/etiología , Ciclosporina/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Posmenopausia/fisiología , Análisis de Regresión , Esteroides/uso terapéutico
13.
Mol Cell Endocrinol ; 113(2): 215-23, 1995 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-8674829

RESUMEN

Obese Zucker rats maintain normal rates of linear growth and circulating concentrations of insulin-like growth factor-I (IGF-I) and of IGF-binding protein-3 (IGFBP-3) in spite of low GH secretion. The mechanisms underlying this GH-independent growth in obesity are unknown. To assess whether the liver expression of the GH receptor (GHR) messenger RNA (mRNA) is increased and/or if the liver expression of IGFBP-3 mRNA is maintained in the obese, Zucker rats of both genders and phenotypes (four groups, n = 6/group) were studied at 12 weeks of age. By Northern analysis, mRNA levels for GHR and GHBP were not increased in obese rats compared to their sex-matched lean littermates; the expression of these two transcripts was sexually dimorphic and the changes in GHBP mRNA/GHR mRNA ratios associated with obesity were sex-specific. In both genders, IGFBP-1 and IGFBP-3 mRNAs were decreased in the obese. We concluded that the GH-independent growth of obese Zucker rats is not due to increased GHR mRNA or to maintained IGFBP-3 mRNA levels in the liver.


Asunto(s)
Hormona del Crecimiento/farmacología , Crecimiento , Hígado/metabolismo , Obesidad/fisiopatología , ARN Mensajero/metabolismo , Receptores de Somatotropina/genética , Animales , Secuencia de Bases , Northern Blotting , Femenino , Hormona del Crecimiento/metabolismo , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Proteína 4 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Datos de Secuencia Molecular , Ratas , Ratas Zucker
14.
Rheum Dis Clin North Am ; 25(2): 379-95, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10356424

RESUMEN

There are a sufficient number of short-term studies with these agents suggesting efficacy equal to that seen in the symptomatic treatment of OA using NSAIDs. Two recent meta-analyses by McAlindon and colleagues and Towheed et al reviewed clinical trials of glucosamine and chondroitin in the treatment of osteoarthritis. The study by McAlindon and co-workers included all double-blind placebo-controlled trials of greater than 4 weeks' duration, testing oral or parenteral glucosamine or chondroitin for treatment of hip or knee osteoarthritis. Thirteen trials (six with glucosamine, seven with chondroitin) met eligibility criteria. The authors used global pain score or the Lequesne index in the index joint as the primary outcome measure and considered the trial positive if improvement in the treatment group was equal to or greater than 25% compared with the placebo group, and was significant (P < or = .05). All 13 studies reviewed were classified as positive, demonstrating large effects, compared with placebo (39.5% [S.D. 21.9] for glucosamine, 40.2% [S.D. 6.4] for chondroitin). The authors concluded that clinical trials of these two agents showed substantial benefit in the treatment of osteoarthritis but provided insufficient information about study design and conduct to allow definitive evaluation. Towheed and colleagues reviewed nine randomized, controlled trials of glucosamine sulfate in osteoarthritis. In seven of the randomized controlled trials, in which they compared glucosamine with placebo, glucosamine was always superior. In two randomized controlled trials comparing glucosamine to ibuprofen, glucosamine was superior in one and equivalent in one. Methodologic problems, including lack of standardized case definition of osteoarthritis and lack of standardized outcome assessment led the authors to conclude that further studies are needed to determine if route of administration is important and whether the therapeutic effect is site specific. A meta-analysis of chondroitin sulfate trials has also been published. Of the 12 published trials, 4 randomized double-blind placebo or NSAID-controlled trials with 227 patients on chondroitin sulfate were entered into the analysis. All four studies showed chondroitin sulfate to be superior to placebo, with respect to Lequesne index, visual analog scale for pain and medication consumption. Significant changes (P < or = .05) were seen in those treated from day 60 to the study endpoints (150 to 180 days). Pooled data demonstrated at least 50% improvement in the study variables in the chondroitin treated group. Discrepancies in some of the study findings reported in the literature may relate to the composition of the nutritional supplements used. Studies in the United States have revealed that a number of preparations claiming to contain certain doses of glucosamine or chondroitin sulfate have significantly less (or none) of the dosages described. Accordingly, it is essential that studies performed with these agents use preparations that are carefully defined in manufacture. The amounts generally administered are glucosamine, 1500 mg, and chondroitin sulfate, 1200 mg, daily. Although glucosamine has been described as effective when used alone, it is probably reasonable to use the combination pending further studies. The average cost is approximately $30 to $45 per month. In the interim, what should physicians tell their patients when they ask whether these agents are effective, or whether they should or should not take them? The authors emphasize that these agents are not FDA-evaluated or recommended for the treatment of OA. They are available as health food supplements, and the number of studies of toxicity, particularly with respect to long-term evaluations, is limited. The pros and cons of these agents and the published data are described so that patients can make a reasonably informed decision as to whether they wish to proceed with use of these agents in therapy. (ABSTRACT TRUNCATED)


Asunto(s)
Sulfatos de Condroitina/uso terapéutico , Colágeno/uso terapéutico , Glucosamina/uso terapéutico , Medicamentos sin Prescripción/uso terapéutico , Osteoartritis/tratamiento farmacológico , Animales , Ensayos Clínicos como Asunto , Humanos
15.
Clin Ther ; 9 Suppl C: 1-14, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3548982

RESUMEN

Thirty-one patients with osteoarthritis of the knee were treated with either diflunisal (n = 17) or naproxen (n = 14) in a 12-week open-label study. Treatment was begun with 500 mg BID of diflunisal or 375 mg BID of naproxen. Patients not showing an adequate response to these dosages were given increases to 750 mg BID of diflunisal (n = 7) or 500 mg BID of naproxen (n = 8). Both drugs achieved statistically significant improvements in pain indices, tenderness, swelling, morning stiffness, functional capacity, knee flexion, and 50-foot walking time, and no significant difference was found between the two drugs. At the end of the study, all patients taking diflunisal and 11/14 patients taking naproxen felt that they had improved with treatment. Drug safety and tolerability were assessed in 21 patients given diflunisal and 16 given naproxen (including patients not part of the efficacy evaluation). Six (29%) patients in the diflunisal group and four (25%) in the naproxen group experienced side effects; three were withdrawn from the diflunisal group and one from the naproxen group because of adverse effects. In general, both drugs were well tolerated.


Asunto(s)
Diflunisal/uso terapéutico , Articulación de la Rodilla , Naproxeno/uso terapéutico , Osteoartritis/tratamiento farmacológico , Salicilatos/uso terapéutico , Adulto , Anciano , Ensayos Clínicos como Asunto , Diflunisal/toxicidad , Tolerancia a Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Naproxeno/toxicidad
16.
Clin Ther ; 13(3): 383-95, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1954640

RESUMEN

The neuropeptide substance P has been implicated in the pathogenesis of inflammation and pain in arthritis. In this double-blind randomized study, 70 patients with osteoarthritis (OA) and 31 with rheumatoid arthritis (RA) received capsaicin (a substance P depletor) or placebo for four weeks. The patients were instructed to apply 0.025% capsaicin cream or its vehicle (placebo) to painful knees four times daily. Pain relief was assessed using visual analog scales for pain and relief, a categorical pain scale, and physicians' global evaluations. Most of the patients continued to receive concomitant arthritis medications. Significantly more relief of pain was reported by the capsaicin-treated patients than the placebo patients throughout the study; after four weeks of capsaicin treatment, RA and OA patients demonstrated mean reductions in pain of 57% and 33%, respectively. These reductions in pain were statistically significant compared with those reported with placebo (P = 0.003 and P = 0.033, respectively). According to the global evaluations, 80% of the capsaicin-treated patients experienced a reduction in pain after two weeks of treatment. Transient burning was felt at the sites of drug application by 23 of the 52 capsaicin-treated patients; two patients withdrew from treatment because of this side effect. It is concluded that capsaicin cream is a safe and effective treatment for arthritis.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Capsaicina/uso terapéutico , Osteoartritis/tratamiento farmacológico , Dolor/tratamiento farmacológico , Administración Tópica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Artritis Reumatoide/fisiopatología , Capsaicina/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Articulación de la Rodilla , Masculino , Persona de Mediana Edad , Osteoartritis/fisiopatología , Dimensión del Dolor
17.
Endocr Rev ; 32(2): 159-224, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20971919

RESUMEN

Plasticity in developmental programming has evolved in order to provide the best chances of survival and reproductive success to the organism under changing environments. Environmental conditions that are experienced in early life can profoundly influence human biology and long-term health. Developmental origins of health and disease and life-history transitions are purported to use placental, nutritional, and endocrine cues for setting long-term biological, mental, and behavioral strategies in response to local ecological and/or social conditions. The window of developmental plasticity extends from preconception to early childhood and involves epigenetic responses to environmental changes, which exert their effects during life-history phase transitions. These epigenetic responses influence development, cell- and tissue-specific gene expression, and sexual dimorphism, and, in exceptional cases, could be transmitted transgenerationally. Translational epigenetic research in child health is a reiterative process that ranges from research in the basic sciences, preclinical research, and pediatric clinical research. Identifying the epigenetic consequences of fetal programming creates potential applications in clinical practice: the development of epigenetic biomarkers for early diagnosis of disease, the ability to identify susceptible individuals at risk for adult diseases, and the development of novel preventive and curative measures that are based on diet and/or novel epigenetic drugs.


Asunto(s)
Desarrollo Infantil/fisiología , Protección a la Infancia , Epigénesis Genética/fisiología , Adolescente , Envejecimiento/fisiología , Niño , Preescolar , Ambiente , Femenino , Impresión Genómica/fisiología , Humanos , Lactante , Recién Nacido , Masculino , Diferenciación Sexual/fisiología
19.
Growth Horm IGF Res ; 19(3): 198-205, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18929499

RESUMEN

CONTEXT: IGF-I and IGFBP-3 play a central role in fetal and postnatal growth and levels are low in short SGA children. The -202 A/C and -185 C/T SNPs are located near elements involved in directing IGFBP3 promoter activity and expression. Changes in promoter CpG methylation status affect transcription factor binding and transcriptional activation of IGFBP3 in vitro. OBJECTIVE: To assess the relationship between IGFBP3 promoter SNPs, IGFBP-3 levels, spontaneous growth and growth response to GH treatment in short prepubertal SGA children. To assess promoter methylation status in a subgroup of short SGA subjects and controls. PATIENTS: 292 Short prepubertal SGA children, 39 short young SGA adults and 85 young adults with normal stature. INTERVENTION: Short prepubertal SGA children received GH 1mg/m(2)/day. OUTCOME MEASURES: Fasting levels of IGF-I and IGFBP-3, baseline and delta height SDS. RESULTS: At baseline, IGFBP-3 levels were highest in SGA children with -202 AA genotype and lower in children with 1 or 2 copies of the C-allele (P<0.001). Children with C(-202)/C(-185) haplotype, compared to children with A(-202)/C(-185) haplotype, had lower IGFBP-3 levels (P=0.003) and were shorter (P=0.03). During GH treatment, children with C(-202)/C(-185) haplotype showed a significantly greater increase in IGFBP-3 SDS and in height SDS than children with A(-202)/C(-185) haplotype, resulting in similar IGFBP-3 levels and similar height SDS after 12 months of GH treatment. CpG methylation patterns showed a trend towards more methylation of CpGs involved in transcription factor binding in short young SGA adults compared to controls. CONCLUSION: Polymorphic variation in the IGFBP3 promoter region is correlated with IGFBP-3 levels, spontaneous growth and response to GH treatment in short SGA children.


Asunto(s)
Metilación de ADN , Epigénesis Genética , Haplotipos/genética , Recién Nacido Pequeño para la Edad Gestacional/sangre , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/genética , Polimorfismo de Nucleótido Simple/genética , Adulto , Estudios de Casos y Controles , Niño , Femenino , Edad Gestacional , Trastornos del Crecimiento/sangre , Trastornos del Crecimiento/genética , Hormona de Crecimiento Humana/farmacología , Humanos , Recién Nacido , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Regiones Promotoras Genéticas
20.
Curr Opin Pediatr ; 7(4): 445-58, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7581651

RESUMEN

Parental, or genomic, imprinting is a newly described form of genetic regulation, leading to the differential behavior of each parental copy of a gene. The precise mechanism responsible for the imprint, or allele-specific behavior of gene transcription, is still unclear; it is thought that modifications not involving the DNA base sequence (therefore, epigenetic as opposed to genetic) have occurred during the production of egg and sperm that mark genes according to parental origin. Several imprinted genes have been identified that also show allelic differences in cytosine methylation and in the timing of their replication during cell division; the relevance of this finding to imprinting mechanisms awaits further clarification. Despite our incomplete knowledge, the importance of the field of imprinting to the pediatrician is in its contribution to our understanding of the transmission behavior of many human diseases and syndromes, particularly those involving abnormal growth and development. Recent advances in the field will no doubt lead to more widely available diagnostic tools with potential applications as far-reaching as the investigation of unexplained fetal loss, prenatal diagnosis, and disease risk counseling.


Asunto(s)
Impresión Genómica/fisiología , ARN no Traducido , Síndrome de Angelman/genética , Animales , Síndrome de Beckwith-Wiedemann/genética , Diabetes Mellitus Tipo 1/genética , Humanos , Factor II del Crecimiento Similar a la Insulina/genética , Neoplasias Renales/genética , Metilación , Ratones , Proteínas Musculares/genética , Neoplasias/genética , Síndrome de Prader-Willi/genética , ARN Largo no Codificante , Transcripción Genética/fisiología , Tumor de Wilms/genética
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