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2.
BMJ Open ; 11(6): e048856, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130964

RESUMO

OBJECTIVE: A key challenge towards a successful COVID-19 vaccine uptake is vaccine hesitancy. We examine and provide novel insights on the key drivers and barriers towards COVID-19 vaccine uptake. DESIGN: This study involved an anonymous cross-sectional online survey circulated across the UK in September 2020. The survey was designed to include several sections to collect demographic data and responses on (1) extent of agreement regarding various statements about COVID-19 and vaccinations, (2) previous vaccination habits (eg, if they had previously declined vaccination) and (3) interest in participation in vaccine trials. Multinominal logistic models examined demographic factors that may impact vaccine uptake. We used principle component analysis and text mining to explore perception related to vaccine uptake. SETTING: The survey was circulated through various media, including posts on social media networks (Facebook, Twitter, LinkedIn and Instagram), national radio, news articles, Clinical Research Network website and newsletter, and through 150 West Midlands general practices via a text messaging service. PARTICIPANTS: There were a total of 4884 respondents of which 9.44% were black, Asian and minority ethnic (BAME) group. The majority were women (n=3416, 69.9%) and of white ethnicity (n=4127, 84.5%). RESULTS: Regarding respondents, overall, 3873 (79.3%) were interested in taking approved COVID-19 vaccines, while 677 (13.9%) were unsure, and 334 (6.8%) would not take a vaccine. Participants aged over 70 years old (OR=4.63) and the BAME community (OR=5.48) were more likely to take an approved vaccine. Smokers (OR=0.45) and respondents with no known illness (OR=0.70) were less likely to accept approved vaccines. The study identified 16 key reasons for not accepting approved vaccines, the most common (60%) being the possibility of the COVID-19 vaccine having side effects. CONCLUSIONS: This study provides an insight into focusing on specific populations to reduce vaccine hesitancy. This proves crucial in managing the COVID-19 pandemic.


Assuntos
COVID-19 , Vacinas , Idoso , Vacinas contra COVID-19 , Estudos Transversais , Feminino , Humanos , Masculino , Pandemias , SARS-CoV-2 , Reino Unido , Vacinação
3.
Trials ; 22(1): 296, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879208

RESUMO

BACKGROUND: Developing a safe and effective vaccine will be the principal way of controlling the COVID-19 pandemic. However, current COVID-19 vaccination trials are not adequately representing a diverse participant population in terms of age, ethnicity and comorbidities. Achieving the representative recruitment targets that are adequately powered to the study remains one of the greatest challenges in clinical trial management. To ensure accuracy and generalisability of the safety and efficacy conclusions generated by clinical trials, it is crucial to recruit patient cohorts as representative as possible of the future target population. Missing these targets can lead to reduced validity of the study results and can often slow down drug development leading to costly delays. OBJECTIVE: This study explores the key factors related to perceptions and participation in vaccination trials. METHODS: This study involved an anonymous cross-sectional online survey circulated across the UK. Statistical analysis was done in six phases. Multi-nominal logistic models examined demographic and geographic factors that may impact vaccine uptake. RESULTS: The survey had 4884 participants of which 9.44% were Black Asian Minority Ethnic (BAME). Overall, 2020 (41.4%) respondents were interested in participating in vaccine trials; 27.6% of the respondents were not interested and 31.1% were unsure. The most interested groups were male (OR = 1.29), graduates (OR = 1.28), the 40-49 and 50-59 age groups (OR = 1.88 and OR = 1.46 respectively) and those with no health issues (OR = 1.06). The least interested groups were BAME (OR = 0.43), those from villages and small towns (OR = 0.66 and 0.54 respectively) and those aged 70 and above (OR = 1.11). CONCLUSIONS: In order to have a vaccination that is generalisable to the entire population, greater work needs to be done in engaging a diverse cohort of participants. Public health campaigns need to be targeted in improving trial recruitment rates for the elderly, BAME community and the less educated rural population.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , Ensaios Clínicos como Assunto , Seleção de Pacientes , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Inquéritos e Questionários , Reino Unido , Vacinação , Adulto Jovem
4.
J Clin Endocrinol Metab ; 101(6): 2545-53, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27003302

RESUMO

CONTEXT: Steroid sulfatase (STS) cleaves the sulfate moiety off steroid sulfates, including dehydroepiandrosterone (DHEA) sulfate (DHEAS), the inactive sulfate ester of the adrenal androgen precursor DHEA. Deficient DHEA sulfation, the opposite enzymatic reaction to that catalyzed by STS, results in androgen excess by increased conversion of DHEA to active androgens. STS deficiency (STSD) due to deletions or inactivating mutations in the X-linked STS gene manifests with ichthyosis, but androgen synthesis and metabolism in STSD have not been studied in detail yet. PATIENTS AND METHODS: We carried out a cross-sectional study in 30 males with STSD (age 6-27 y; 13 prepubertal, 5 peripubertal, and 12 postpubertal) and 38 age-, sex-, and Tanner stage-matched healthy controls. Serum and 24-hour urine steroid metabolome analysis was performed by mass spectrometry and genetic analysis of the STS gene by multiplex ligation-dependent probe amplification and Sanger sequencing. RESULTS: Genetic analysis showed STS mutations in all patients, comprising 27 complete gene deletions, 1 intragenic deletion and 2 missense mutations. STSD patients had apparently normal pubertal development. Serum and 24-hour urinary DHEAS were increased in STSD, whereas serum DHEA and testosterone were decreased. However, total 24-hour urinary androgen excretion was similar to controls, with evidence of increased 5α-reductase activity in STSD. Prepubertal healthy controls showed a marked increase in the serum DHEA to DHEAS ratio that was absent in postpubertal controls and in STSD patients of any pubertal stage. CONCLUSIONS: In STSD patients, an increased 5α-reductase activity appears to compensate for a reduced rate of androgen generation by enhancing peripheral androgen activation in affected patients. In healthy controls, we discovered a prepubertal surge in the serum DHEA to DHEAS ratio that was absent in STSD, indicative of physiologically up-regulated STS activity before puberty. This may represent a fine tuning mechanism for tissue-specific androgen activation preparing for the major changes in androgen production during puberty.


Assuntos
Sulfato de Desidroepiandrosterona/metabolismo , Desidroepiandrosterona/metabolismo , Ictiose Ligada ao Cromossomo X/metabolismo , Puberdade/metabolismo , Esteril-Sulfatase/genética , Testosterona/metabolismo , Adolescente , Adulto , Criança , Colestenona 5 alfa-Redutase/genética , Colestenona 5 alfa-Redutase/metabolismo , Estudos Transversais , Desidroepiandrosterona/sangue , Desidroepiandrosterona/urina , Sulfato de Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/urina , Humanos , Ictiose Ligada ao Cromossomo X/genética , Masculino , Metaboloma , Metabolômica , Reação em Cadeia da Polimerase Multiplex , Mutação , Testosterona/sangue , Testosterona/urina , Adulto Jovem
5.
Artigo em Inglês | MEDLINE | ID: mdl-26843960

RESUMO

UNLABELLED: Estrogen is used to induce puberty in peripubertal girls with hypogonadism. Although both synthetic and natural forms are available, along with different routes of administration, in the UK oral ethinyl estradiol and the low-dose oral contraceptive pill are commonly used as hormone replacement therapy for practical reasons. We present five peripubertal girls (aged 12.5-14.9 years) with hypogonadism (two with primary hypogonadism due to Turner syndrome and three with central (secondary) hypogonadism as part of multiple pituitary hormone deficiency) who for a variety of reasons have received milligram doses of estradiol (E2) in error for between 6 weeks and 6 months, instead of the expected microgram doses of ethinyl estradiol. Although there are no direct comparisons in peripubertal girls between synthetic and natural estrogens, all girls had vaginal bleeding whilst receiving the milligram doses and have ended up with reduced final heights, below the 9th centile in 1 and below the 2nd centile in 4. Whilst reduction in final height may be part of the underlying condition (especially in Turner syndrome) the two girls with height predictions performed prior to receiving the estrogen overdose have not achieved their predicted height. Estrogen is one of the few drugs which is available in both milligram and microgram formulations. Clinicians need to be alert to the possibility of patients receiving the wrong formulation and dosage in error. LEARNING POINTS: Girls with primary and secondary gonadal failure require assistance with pubertal induction.Although several different formulations and route of administration are available, for practical reasons, the majority of girls in the UK receive oral ethinyl estradiol.Estrogen preparations are available in both milligram and microgram formulations, with potential for receiving the wrong dose.Girls receiving milligram rather than microgram preparations all had vaginal bleeding and a short final height.

6.
Clin Endocrinol (Oxf) ; 80(1): 85-91, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23745601

RESUMO

INTRODUCTION: Obesity has been associated with a positive influence on bone mass. This is thought to be due to a mechanical load exerted on the skeleton, together with various hormones and adipocytokines that control appetite and weight, such as leptin, some of which directly affect bone mass. However, there are conflicting reports of the association between fat mass and bone mass in children. Animal studies demonstrate increased bone mass where there is impaired central leptin signalling. Hypothalamic damage can cause abnormal central leptin action, which contributes to the development of obesity. OBJECTIVE: The objective of this study was to investigate the relationship between body composition and bone mass in hypothalamic and simple childhood obesity, in conjunction with the effect of the adipocytokines, leptin and adiponectin. DESIGN: This was a cross-sectional study of three groups of children, those with hypothalamic obesity (HO), those with congenital hypopituitarism (CH) and those with simple obesity (SO). RESULTS: A total of 65 children (HO = 26 [11 males], CH = 17 [eight males] and SO = 22 [15 males]) had body composition assessed using dual-energy X-ray absorptiometry together with measurement of serum leptin and adiponectin. No significant differences were seen in bone mass once bone density (BMD) was adjusted for differences in body size between groups. Significantly elevated levels of leptin and adiponectin were seen in the HO group compared with the SO group (P < 0·01, P < 0·05, respectively). CONCLUSION: Adiposity is associated with increased bone mass; however, this relationship is complex. Despite the presence of hyperleptinaemia, increased bone mass in the HO group was not seen. This may be due to the effects of other factors such as adiponectin, abnormal hypothalamic signalling, pituitary hormone deficiencies and disruption of normal homoeostatic mechanisms within the hypothalamus.


Assuntos
Composição Corporal/fisiologia , Leptina/metabolismo , Obesidade/metabolismo , Absorciometria de Fóton , Adiposidade/fisiologia , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Hipopituitarismo/metabolismo , Masculino
7.
J Pediatr Endocrinol Metab ; 26(11-12): 1041-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23751384

RESUMO

AIM: Cranial diabetes insipidus (CDI) is rare in infants with no guidelines on its management. We describe the first case series, characterizing the clinical features and treatment challenges. METHOD: Retrospective case note review of infants diagnosed with CDI between April 1992 and February 2011. RESULTS: Nineteen infants (52% male) were identified. Eight were born preterm. Median (range) age at diagnosis was 24 days (5-300); preterm babies were younger at diagnosis (21 vs. 46 days). In 58% (11/19) of infants, hypernatraemia was discovered incidentally. In 37% of cases there was associated midline anomalies, however, only four patients (21%) had absent posterior pituitary signal on a magnetic resonance imaging brain scan. The most frequent (5/19) underlying diagnosis was septo-optic dysplasia. Eight patients had isolated CDI and 11 had multiple pituitary hormone deficiencies. Isolated CDI tended to be more common in preterm, compared to term babies (p=0.11). Des-amino arginine vasopressin (DDAVP) was administered intranasally in eight and orally in 11 infants. Plasma sodium nadir following DDAVP administration was lower following intranasal compared to an oral route of administration (median: 128 vs. 133 mmol/L, p=0.022). No cases resolved on follow-up. CONCLUSIONS: CDI in infants is often diagnosed incidentally. Aetiology, clinical, and imaging features are very variable, with some differences between preterm and term infants. Oral DDAVP appears to be superior to intranasal with less pronounced serum sodium fluctuations.


Assuntos
Diabetes Insípido/terapia , Crânio/patologia , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Imageamento por Ressonância Magnética , Estudos Retrospectivos
8.
Pediatr Blood Cancer ; 60(6): E7-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23255311

RESUMO

Turner syndrome (TS) (approximately 1:5,000 births) and craniopharyngioma (CP) (1:50,000 children) are both rare conditions. We present three cases of TS with CP, an association not previously described. Visual failure, poor growth or headache led to MRI diagnosis of CP. Whilst two had evidence of hypopituitarism at diagnosis of CP, they all developed hypopituitarism following surgical debulking. Two required radiotherapy due to regrowth. Whether CP and TS share a similar aetiology is unknown. Clinicians need to be aware of this association, and should perform urgent MRI scanning in TS patients with headache, visual impairment or clinical/biochemical evidence of hypopituitarism.


Assuntos
Craniofaringioma/complicações , Neoplasias Hipofisárias/complicações , Síndrome de Turner/complicações , Adolescente , Pré-Escolar , Craniofaringioma/patologia , Craniofaringioma/cirurgia , Feminino , Humanos , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia
9.
Horm Res Paediatr ; 78(2): 81-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22907285

RESUMO

BACKGROUND: Septo-optic dysplasia (SOD) is a disorder with postulated environmental and genetic aetiology. This study delineates clinical features and potential perinatal environmental factors along with epidemiology in SOD children. METHODS: Assessment of patients with SOD triad features in the UK West Midlands region. RESULTS: Of 227 patients identified between 1998 and 2009 with 1 or more feature of the triad, 55 had midline defects, 149 had optic nerve hypoplasia and 132 had hypopituitarism. Eighty-eight children (52% males; incidence 8.3/100,000 live births) had SOD defined as 2 out of 3 features and 21 (24%) had all 3. Sixty-one percent had anterior pituitary deficiency and 21.5% had diabetes insipidus. Median maternal/paternal ages in SOD were 21 and 23.5 years, compared to UK means of 29.3 and 32.4 years (p < 0.001). First trimester bleeding was markedly increased at 12/48 (25%) compared to 0.07% in the UK (p < 0.001). Ethnicity showed a non-significant higher prevalence in Afro-Caribbean and mixed race groups, and significantly lower prevalence (p = 0.004) in South Asian groups compared to West Midland and Birmingham city data: 8% versus 2.5 and 6.7%, 9% versus 1.8 and 3.2% and 3% versus 8.4 and 21%, respectively. CONCLUSIONS: SOD is associated with younger maternal and paternal age, primigravida births and ethnic differences. Increased first trimester bleeding may indicate that SOD is a vascular disruption sequence.


Assuntos
Idade Materna , Idade Paterna , Displasia Septo-Óptica/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Diabetes Insípido/complicações , Diabetes Insípido/epidemiologia , Feminino , Hemorragia/complicações , Hemorragia/epidemiologia , Humanos , Lactente , Masculino , Doenças da Hipófise/complicações , Doenças da Hipófise/epidemiologia , Gravidez , Complicações Hematológicas na Gravidez/epidemiologia , Primeiro Trimestre da Gravidez , Fatores de Risco , Displasia Septo-Óptica/etiologia , Reino Unido
10.
Pediatr Dermatol ; 27(2): 178-81, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20537071

RESUMO

Diabetes mellitus is associated with a range of dermatologic presentations, including granuloma annulare and necrobiosis lipoidica diabeticorum. Granuloma annulare occurs earlier than necrobiosis lipoidica diabeticorum and the association with diabetes mellitus is much weaker. We describe two children with diabetes who both developed granuloma annulare and later, necrobiosis lipoidica diabeticorum. We postulate that the early onset and transient nature of granuloma annulare, compared with the later onset and persistence of necrobiosis lipoidica diabeticorum, might account for the different apparent rates of association with diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Granuloma Anular/etiologia , Necrobiose Lipoídica/etiologia , Adolescente , Criança , Doença Crônica , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Granuloma Anular/tratamento farmacológico , Granuloma Anular/patologia , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Metformina/uso terapêutico , Necrobiose Lipoídica/tratamento farmacológico , Necrobiose Lipoídica/patologia
11.
Pediatr Endocrinol Rev ; 6 Suppl 4: 523-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19550387

RESUMO

Noonan syndrome (NS) is a phenotypically heterogeneous condition frequently associated with short stature. Genetic investigations have identified mutations in several genes, e.g. PTPN11, KRAS, RAF and SOS1 in patients with the NS phenotype and related disorders such as LEOPARD, Costello and Cardiofacio- cutaneous syndromes. In NS, PTPN11 mutations are present in 29-60% of cases. The degree of short stature does not associate closely with the presence of a mutation; however, some PTPN11-positive patients have decreased growth hormone (GH)-dependent growth factors consistent with mild GH insensitivity. GH therapy induces short-term increases in height velocity over 1-3 years, and is likely to improve adult height.


Assuntos
Transtornos do Crescimento/tratamento farmacológico , Transtornos do Crescimento/etiologia , Hormônio do Crescimento Humano/uso terapêutico , Síndrome de Noonan/complicações , Síndrome de Noonan/tratamento farmacológico , Adulto , Estatura , Criança , Feminino , Genótipo , Cardiopatias Congênitas/complicações , Humanos , Masculino , Proteínas Quinases Ativadas por Mitógeno/genética , Mutação , Síndrome de Noonan/genética , Fenótipo , Proteínas ras/genética
12.
Eur J Endocrinol ; 159(6): 791-7, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18819946

RESUMO

BACKGROUND: Obesity following hypothalamic damage is often severe and resistant to lifestyle changes. Disruption of hypothalamic feedback mechanisms that maintain energy homeostasis may be responsible for this intractable obesity. Adipocytokines including insulin and leptin are also known to be important regulators of appetite and weight. OBJECTIVE: To investigate the role of insulin, leptin, adiponectin and resistin in the aetiology of hypothalamic obesity (HO). DESIGN: This was a cross-sectional study of three groups of children, those with HO, congenital hypopituitarism (CH) and simple obesity (SO). RESULTS: A total of 69 children (HO=28, CH=18, SO=23) had leptin, resistin, adiponectin and insulin measured. Although fasting hyperinsulinaemia and insulin resistance were demonstrated, no differences in insulin or insulin resistance were seen between the groups. The HO group, however, had higher levels of leptin, adiponectin and resistin, which persisted even after adjusting for fat mass, compared with the other groups (P<0.05). CONCLUSION: No differences in fasting hyperinsulinaemia or insulin resistance were seen between the groups; however, leptin levels are elevated, even after adjusting for fat mass, suggesting that an element of leptin resistance is associated with HO. This is consistent with the inability of leptin to act on the hypothalamus, either due to transport across the blood-brain barrier or dysfunctional receptors. The lack of response to leptin may be more important in the development of obesity in these individuals, and the fasting hyperinsulinaemia is a result of the increased adipose tissue rather than the cause of the weight gain.


Assuntos
Jejum/sangue , Hiperinsulinismo/sangue , Doenças Hipotalâmicas/sangue , Leptina/sangue , Obesidade/sangue , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Hiperinsulinismo/complicações , Hipopituitarismo/sangue , Hipopituitarismo/complicações , Doenças Hipotalâmicas/complicações , Hipotálamo/metabolismo , Hipotálamo/patologia , Masculino , Obesidade/complicações
13.
J Clin Endocrinol Metab ; 93(7): 2588-93, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18413428

RESUMO

CONTEXT: Obesity after hypothalamic damage is often severe and resistant to lifestyle changes. It is postulated that differences in basal metabolic rate (BMR) and physical activity may contribute to hypothalamic obesity (HO). OBJECTIVE: Our objective was to investigate the role of energy expenditure, BMR, and physical activity in the etiology of hypothalamic obesity. DESIGN: This was a cross-sectional study of three groups of children: those with HO, congenital hypopituitarism (CH), and simple obesity (SO). RESULTS: A total of 47 children (HO = 18, CH = 13, and SO = 16) had BMR measured, using indirect calorimetry (Deltatrac II). A lower BMR was seen in the HO group, which remained even after adjusting for lean mass. Physical activity, assessed using triaxial accelerometry, demonstrated longer activity periods in the HO group, although the degree of activity was reduced. No significant differences were seen in calorie intake. CONCLUSION: Energy expenditure, rather than energy intake, has a greater role in the development of obesity after cranial tumor therapy. Reductions in BMR and physical activity, leading to a positive energy balance and weight gain despite an age-appropriate calorie intake, may contribute to hypothalamic obesity.


Assuntos
Metabolismo Basal , Exercício Físico , Hipotálamo/fisiologia , Obesidade/etiologia , Adolescente , Criança , Estudos Transversais , Carboidratos da Dieta/administração & dosagem , Ingestão de Energia , Metabolismo Energético , Feminino , Humanos , Masculino , Hormônios Tireóideos/sangue
14.
Clin Endocrinol (Oxf) ; 67(1): 20-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17466011

RESUMO

OBJECTIVE: 17beta-hydroxysteroid dehydrogenase type 3 isoenzyme (17beta-HSD3) is required to produce testosterone for male sex differentiation. Mutations in the HSD17B3 gene cause 17betaHSD3 deficiency and result in XY sex reversal of varying degree. We report the phenotypes of 14 subjects with 17betaHSD3 deficiency in relation to sex of rearing, androgen production, and HSD17B3 mutations. DESIGN: Cases were identified through the Cambridge Disorders of Sex Development Database where detailed clinical information was recorded, results of hCG stimulation tests were available, and HSD17B3 mutation was identified. RESULTS: Fourteen subjects from seven pedigrees (four consanguineous) had the following seven mutations: A56T, N130S, E215D, S232L, C268Y, V205E, and a novel mutation M197K. XY sex reversal was classified as complete in 10 infants at birth. Inguinal masses suggestive of androgen insensitivity syndrome (AIS) occurred in five infants. Contrasexual virilization reminiscent of 5alpha-reductase deficiency occurred in four subjects at puberty. The median (range) testosterone : androstenedione (T/A) ratio after a short hCG stimulation test was 0.32 (0.12-3.4). The S232L mutation identified in three affected family members caused isolated, severe hypospadias in one member who was raised male; virilization occurred despite in vitro studies showing an inactive mutant enzyme. Ratios of T/A in this pedigree were more than 0.8. CONCLUSION: XY sex reversal is sufficiently variable in 17betaHSD3 deficiency to cause problems in accurate diagnosis, particularly in distinguishing it from AIS. It should be considered in undervirilized male infants with normal Wolffian duct structures, absent Müllerian ducts, and normal adrenal steroid biosynthesis; or when an assigned female subject virilizes at puberty. Elevated hCG-stimulated T/A ratio may occur, and sex of rearing may not be concordant within affected families with the same HSD17B3 mutation. The T/A ratio, mutation analysis and functional analysis of the mutant enzyme taken in isolation, respectively, may not conclusively establish a diagnosis of 17betaHSD3 deficiency in undervirilized male subjects; the reasons for these discrepancies remain unknown.


Assuntos
17-Hidroxiesteroide Desidrogenases/deficiência , Transtornos do Desenvolvimento Sexual/patologia , Genitália/patologia , 17-Hidroxiesteroide Desidrogenases/genética , Adolescente , Transtornos do Desenvolvimento Sexual/genética , Feminino , Humanos , Lactente , Masculino , Mutação de Sentido Incorreto , Linhagem , Fenótipo , Virilismo/genética , Virilismo/patologia
15.
J Clin Invest ; 116(9): 2442-55, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16932809

RESUMO

The transcription factor SOX2 is expressed most notably in the developing CNS and placodes, where it plays critical roles in embryogenesis. Heterozygous de novo mutations in SOX2 have previously been associated with bilateral anophthalmia/microphthalmia, developmental delay, short stature, and male genital tract abnormalities. Here we investigated the role of Sox2 in murine pituitary development. Mice heterozygous for a targeted disruption of Sox2 did not manifest eye defects, but showed abnormal anterior pituitary development with reduced levels of growth hormone, luteinizing hormone, and thyroid-stimulating hormone. Consequently, we identified 8 individuals (from a cohort of 235 patients) with heterozygous sequence variations in SOX2. Six of these were de novo mutations, predicted to result in truncated protein products, that exhibited partial or complete loss of function (DNA binding, nuclear translocation, or transactivation). Clinical evaluation revealed that, in addition to bilateral eye defects, SOX2 mutations were associated with anterior pituitary hypoplasia and hypogonadotropic hypogonadism, variable defects affecting the corpus callosum and mesial temporal structures, hypothalamic hamartoma, sensorineural hearing loss, and esophageal atresia. Our data show that SOX2 is necessary for the normal development and function of the hypothalamo-pituitary and reproductive axes in both humans and mice.


Assuntos
Proteínas de Ligação a DNA/genética , Anormalidades do Olho/genética , Proteínas HMGB/genética , Hipotálamo/anormalidades , Mutação , Hipófise/anormalidades , Transativadores/genética , Fatores de Transcrição/genética , Anormalidades Múltiplas/genética , Adulto , Animais , Criança , Feminino , Humanos , Lactente , Masculino , Camundongos , Fatores de Transcrição SOXB1
18.
Br J Haematol ; 120(2): 353-8, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12542498

RESUMO

Reduction of bone density and its associated morbidity is recognized in young adults with beta-thalassaemia major, but the aetiology is not clear. This study used dual X-ray absorptiometry (DXA) to look at bone mineral apparent density (BMAD) in children and young adults with thalassaemia in a predominantly Asian population, in the context of sexual maturation. Fifty-five patients were scanned (mean age 13.8 years, range 5.9-37.5) and BMAD z-scores were calculated using normal data from locally recruited control subjects. Eighteen patients had undergone bone marrow transplantation (BMT) and the remainder were on a transfusion/chelation regimen. BMAD z-scores ranged from -3.3-1.6 with a mean of -0.92. No difference in BMAD was found between those patients treated conventionally and those who had undergone BMT. When comparing mean BMAD z-score according to sexual maturation, there was a highly significant difference (P < 0.0001) between those whose pubertal maturation was age appropriate (mean z-score -0.22), when compared with those who had disordered puberty (mean z-score -1.82). We have shown that failure to progress normally through puberty is highly significant in the failure of adequate bone mineralization and achievement of peak bone mass in thalassaemic patients. The management of these patients should therefore be pro-active to anticipate problems and facilitate normal sexual maturation.


Assuntos
Densidade Óssea , Puberdade Tardia/fisiopatologia , Talassemia beta/fisiopatologia , Absorciometria de Fóton , Adolescente , Adulto , Ásia/etnologia , Transplante de Medula Óssea , Estudos de Casos e Controles , Quelantes/uso terapêutico , Criança , Pré-Escolar , Inglaterra , Feminino , Humanos , Masculino , Talassemia beta/terapia
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