Double layer SiO2-TiO2 sol-gel thin films on glass for antireflection, antifogging, and UV recoverable self-cleaning.

Double layer thin films, mechanically stable and adhering to glass, were produced through the sol-gel process, using tetraethyl orthosilicate and titanium butoxide as precursors. The refractive index of the titania and silica-titania composite layers were typically 2.1 and 1.7, and their physical thicknesses were approximately 65 nm and 81 nm, respectively, as determined by ellipsometry. These optical constants allowed attainment of quarter-wave optical thicknesses at the center of the visible spectrum (550 nm) as designed, with an increase of 3.4% in transmittance. The nanometric surface roughness, measured by optical profilometry, was effective to decrease light scattering and water contact angles to below 10°. As novelty in dip-coated sol-gel films, superhydrophilicity for self-cleaning, antifogging, and antireflection in the mid-visible spectrum were simultaneously attained with durability of 9 weeks in the dark. Further application of UV light allowed regeneration of contact angles for self-cleaning.

Una década del Registro de Artroplastias de Cataluña (RACat): exhaustividad, variabilidad y supervivencia de las prótesis entre 2005 y 2014 / A decade of the Catalonian Arthroplasty Register (RACat): variability, exhaustivity, and survival of prostheses between 2005 and 2014

Antecedentes y objetivo. El Registro de Artroplastias de Cataluña (RACat) es un registro poblacional basado en el sistema sanitario público para analizar y evaluar artroplastias de cadera y rodilla en Cataluña. El objetivo de este estudio es presentar los resultados tras 10 años de funcionamiento (de enero de 2005 a diciembre de 2014). Metodología. A partir de la información del RACat y del conjunto mínimo básico de datos al alta hospitalaria, se analizó la calidad y exhaustividad de los datos y se realizaron análisis descriptivos de pacientes, prótesis y proceso asistencial. Además, se analizó la supervivencia calculando la incidencia acumulada de revisión (según causa de intervención en artroplastias de cadera y preservación o sacrificio del ligamento cruzado posterior en artroplastia de rodilla) y la asociación entre riesgo de revisión y técnica de fijación de las prótesis como modelos de riesgos competitivos ajustados por sexo, edad y comorbilidad. Resultados. El principal motivo de intervención en artroplastias primarias de cadera y rodilla fue la artrosis. La incidencia acumulada de revisión a los 10 años fue del 3,9% en artroplastias de cadera causadas por artrosis y del 2,3% en las causadas por fractura. Las artroplastias de rodilla que conservan el ligamento cruzado posterior son el 4,4% y las que no lo conservan, el 5,1%. Discusión. El RACat se consolida como herramienta para la evaluación de las artroplastias con gran potencial en el análisis de la efectividad a medio y largo plazo, el estudio de la variabilidad de la práctica clínica y la vigilancia poscomercialización (AU)

Background and aim. The Catalonian Arthroplasty Register (RACat) is a public health-based population register used to analyse and evaluate hip and knee replacements in Catalonia. The aim of this study is to present the outcomes after 10 years in operation (January 2005-December 2014). Methodology. Using the information from the RACat and the minimum basic data set at hospital discharge, an analysis was made of the quality and exhaustivity of the data, as well as a descriptive analysis of the patients, prostheses, and care process. Survival was also analysed by calculating the accumulated incidence of revisions (according to the cause of intervention in hip replacements and conservation or sacrifice of the posterior cruciate ligament in knee replacement). The relationship between revision risk and the fixation technique of the prosthesis is also analysed, using competitive risk models adjusted for gender, age, and comorbidities. Results. The main reason for the primary hip and knee replacement surgery was arthrosis. The accumulated incidence of revisions at 10 years was 3.9% in hip replacements caused by arthrosis, and 2.3% in those caused by fracture. Conservation of the posterior cruciate ligament was achieved in 4.4% of knee replacements, with sacrifice in 5.1%. Discussion. The RACat is consolidated as a tool for the evaluation of joint replacements, with great potential in the analysis of medium and long-term efficacy, the study of the variability in clinical practice, and post-marketing surveillance (AU)

A decade of the Catalonian Arthroplasty Register (RACat): Variability, exhaustivity, and survival of prostheses between 2005 and 2014. / Una década del Registro de Artroplastias de Cataluña (RACat): exhaustividad, variabilidad y supervivencia de las prótesis entre 2005 y 2014.

BACKGROUND AND AIM: The Catalonian Arthroplasty Register (RACat) is a public health-based population register used to analyse and evaluate hip and knee replacements in Catalonia. The aim of this study is to present the outcomes after 10 years in operation (January 2005-December 2014). METHODOLOGY: Using the information from the RACat and the minimum basic data set at hospital discharge, an analysis was made of the quality and exhaustivity of the data, as well as a descriptive analysis of the patients, prostheses, and care process. Survival was also analysed by calculating the accumulated incidence of revisions (according to the cause of intervention in hip replacements and conservation or sacrifice of the posterior cruciate ligament in knee replacement). The relationship between revision risk and the fixation technique of the prosthesis is also analysed, using competitive risk models adjusted for gender, age, and comorbidities. RESULTS: The main reason for the primary hip and knee replacement surgery was arthrosis. The accumulated incidence of revisions at 10 years was 3.9% in hip replacements caused by arthrosis, and 2.3% in those caused by fracture. Conservation of the posterior cruciate ligament was achieved in 4.4% of knee replacements, with sacrifice in 5.1%. DISCUSSION: The RACat is consolidated as a tool for the evaluation of joint replacements, with great potential in the analysis of medium and long-term efficacy, the study of the variability in clinical practice, and post-marketing surveillance.

[Systemic lupus erythematosus presenting as severe alveolar hypoventilation and the shrinking lung syndrome]. / Hypoventilation alvéolaire sévère révélant un shrinking lung syndrome lupique.

INTRODUCTION: The shrinking lung syndrome (SLS) is a rare complication of systemic lupus erythematosus. CASE REPORT: A 69-year-old man presented with exertional dyspnoea, muscle weakness, and weight loss of 15kg in 6months. Pulmonary function tests revealed a restrictive lung disorder, with a dramatic decrease in maximal inspiratory pressure (17% of theoretical value), and alveolar hypoventilation (pH 7.43; PaCO2 55mmHg). A thoracic CT-scan showed bilateral diaphragmatic elevation. The creatinine phophokinase level was increased at 280U/L. Progress was marked by a rapidly increasing respiratory acidosis (pH 7.24, PaCO2 109mmHg) requiring invasive ventilation. Auto-immune studies revealed positive anti-nuclear antibodies (1/800) and positive anti-native DNA antibody at 45U/L. Treatment with systemic corticosteroids led to an initial improvement but it was not possible to discontinue mechanical ventilation. The outcome was fatal. Autopsy did not reveal any other cause and a diagnosis of the SLS associated with lupus was confirmed. CONCLUSION: The interesting features of this case report consist of: 1) the presentation of the SLS as an alveolar hypoventilation with a fatal outcome, 2) the presentation of systemic lupus as SLS.

Work-related respiratory symptoms in Champagne vineyard workers.

BACKGROUND: Vineyard workers (VW) are exposed to various respiratory allergens. The aims of the study were to determine the prevalence of work related respiratory symptoms (WRS) in Champagne VW in France and to analyze the relationships between symptoms, occupational exposure and sensitization profile. METHODS: VW of Reims area were prospectively recruited between 2007 and 2010. Demographic and occupational characteristics were recorded. Respiratory symptoms were scored for each month of the past year. Results of respiratory functional tests and skin prick tests for common respiratory allergens, grape moulds and vine pollen were recorded. RESULTS: 307 subjects were included. The prevalence of WRS was 11%. Compared to subjects with symptoms unrelated to work, subjects with WRS were more frequently sensitized to gramineae (34% vs 18%, p = 0.05), described ocular itching (74% vs 37%, p < 0.001) and seasonal symptoms (88% vs 69%, p = 0.03) mainly during lifting and trellising (57% vs 17%, p < 0.001). CONCLUSION: WRS are frequent in Champagne WV and are associated with a sensitization to gramineae and with activities performed close to vine in late spring.

[Eosinophilic pleuritic: An unusual complication of treatment with an angiotensin converting enzyme inhibitor]. / Pleurésie à éosinophiles: une complication rare d'un traitement par inhibiteur de l'enzyme de conversion de l'angiotensine.

BACKGROUND: Eosinophilic pleural effusions are defined by an eosinophil count ≥10% in pleural fluid and represent approximately 10% of exudative pleural effusions. OBSERVATION: We report the first case of eosinophilic pleural effusion occurring due to lisinopril treatment. Improvement after drug discontinuation and recurrence after reintroduction indicated that lisinopril was responsible for the effusion. CONCLUSION: The main causes of eosinophilic pleural effusions are infections including tuberculosis, and malignancies. Drug-induced eosinophilic pleural effusions have only rarely been described, mainly caused by cardiovascular or neuropsychiatric medicines.

Respuesta a la carta «El registro español de artroplastias» de los Dres. M. Fernández Fairén, R. Llopis y A. Rodríguez / Response to the letter «Spanish arthoplasty register» from M. Fernández Fairén, R. Llopis and A. Rodríguez

No disponible

[Post-infectious autobullectomy]. / Autobullectomie post-infectieuse.

INTRODUCTION: Bullous emphysema is defined as an airspace of more than 10mm in diameter. The spontaneous regression or disappearance of a bulla is unusual, described as an "autobullectomy". CASE REPORT: We report the case of a 37-year-old man with a 10-pack/year history of smoking, a history of pneumothorax surgically treated in 2005, and emphysema with a bulla in the right upper lobe. In September 2010, the patient was hospitalized for a community-acquired pneumonia associated with an air-fluid level in the bulla. Clinical symptoms improved with a course of antibiotics (levofloxacin, ceftriaxone) for 3 weeks. Chest X-rays showed a progressive decrease in the size of the bulla. In June 2011, a chest CT scan showed complete regression of the bulla in the right upper lobe. CONCLUSIONS: We report the complete regression of a bulla after infection, leading to an "autobullectomy". It can be hypothesized that the mechanisms might involve fibrosis of the walls and/or the obstruction of the bronchus supplying the bulla.

[The Proteus syndrome: a rare cause of pulmonary emphysema]. / Le syndrome de Protée : une cause exceptionnelle d'emphysème pulmonaire.

INTRODUCTION: The Proteus syndrome is a rare genetic disease which is characterized by the overgrowth of tissues, especially bone, connective and adipose tissue. This condition is related to a somatic mosaic activating mutation in the AKT1 oncogene. CASE REPORT: We report the case of a 25-year-old man, diagnosed with the Proteus syndrome at the age of 6 months. He exhibited an asymmetric overgrowth of the extremities leading to bilateral amputation of the legs at the age of 10 years. He was hospitalized for acute respiratory failure due to a bronchopulmonary infection. Severe bullous pulmonary emphysema, predominantly on the left, with mediastinal deviation, was diagnosed. The patient recovered with antibiotics. An assessment 2 months later revealed mild hypoxaemia (PaO2=75 mmHg) and severe airflow limitation (FEV1=1260 mL [28% th.], FEV1/V C=69%) with hyperinflation (TLC=7840 mL [107% th.], RV=6010 mL [253% th.]). CONCLUSION: The Proteus syndrome is a very rare cause of pulmonary emphysema. The pathophysiology of emphysema in this syndrome is unknown. It can be hypothesized that the development of pulmonary cysts leading to emphysema may share the same AKT1 activation pathway with lymphangioleiomyomatosis.

[Arthroplasty registers as post-marketing surveillance systems: the Catalan Arthroplasty Register]. / Los registros de artroplastias como sistemas de vigilancia poscomercialización: el Registro de Artroplastias de Cataluña.

OBJECTIVE: The aim is to present the functioning and results of the Catalan Arthroplasty Registry (RACat). MATERIAL AND METHOD: The RACat arose by the initiative of the Catalan Society of Orthopaedic Surgery and Traumatology, the Catalan Health Service (CHS) and the Catalan Agency for Health Information Assessment and Quality. Publicly funded hospitals sent information through the Internet (CHS Applications website) on knee and hip arthroplasties: patient identification, hospital, joint (hip/knee), type (primary/revision), side of operation, date of surgery and prosthesis (manufacturer's name and reference number). The quality of the data is analysed regularly. We estimate the risk of replacement by the Kaplan-Meier method. RESULTS: A total of 52 hospitals out of 62 send data to RACat, and information on 36,951 knee and 26,477 hip arthroplasties is available. Data quality improved between 2005 and 2010. In 2010 coverage exceeded 70%, with side of operation 97%, and prostheses identification of 80%. The risk of replacement at three years was 3.3% (95% CI:3.1-3.6) for knee, 2.9% (95% CI:2.5-3.3) for total hip, and 2.5% (95% CI:2.0-3.1) for partial hip. DISCUSSION: Risk of replacement is higher than that observed in other registers, although data quality and its improvement over time should be taken into account. CONCLUSIONS: The information available in the RACat will help to establish a standard that will enable hospitals to compare results.

Los registros de artroplastias como sistemas de vigilancia poscomercialización: el Registro de Artroplastias de Cataluña / Arthroplasty registers as post-marketing surveillance systems: the Catalan Arthroplasty Register

Objetivo. El objetivo de este trabajo es presentar el funcionamiento y los resultados del Registro de Artroplastias de Cataluña (RACat). Material y método. El RACat surgió por iniciativa de la Sociedad Catalana de Cirugía Ortopédica y Traumatología, el Servicio Catalán de la Salud (SCS) y la Agencia de Información, Evaluación y Calidad en Salud. Los hospitales financiados públicamente envían mediante Internet (portal de aplicaciones, SCS) información sobre las artroplastias de rodilla y cadera: identificación del paciente, hospital, articulación (cadera/rodilla), tipo (primaria/recambio), lateralidad, fecha de cirugía y prótesis (fabricante y número de referencia). La calidad de los datos se analiza periódicamente. El riesgo de recambio se estima mediante el método de Kaplan-Meier. Resultados. En total 52 hospitales de 62 envían datos al RACat que dispone de información sobre 36.951 artroplastias de rodilla y 26.477 de cadera. La calidad de los datos mejoró entre 2005 y 2010, superando la cobertura el 70%, la información sobre lateralidad el 97% y la identificación de prótesis el 80%. El riesgo de recambio a los 3 años fue del 3,3% (IC 95%:3,1-3,6) para rodilla, del 2,9% (IC 95%:2,5-3,3) para las totales de cadera, y del 2,5% (IC 95%:2,0-3,1) para las parciales. Discusión. El riesgo de recambio es superior al observado en otros registros, aunque es necesario tener en cuenta la calidad de la información disponible y su mejora en el tiempo. Conclusiones. La información disponible en el RACat permitirá establecer un estándar de referencia que permita a los hospitales evaluar sus resultados (AU)

Objective. The aim is to present the functioning and results of the Catalan Arthroplasty Registry (RACat). Material and method. The RACat arose by the initiative of the Catalan Society of Orthopaedic Surgery and Traumatology, the Catalan Health Service (CHS) and the Catalan Agency for Health Information Assessment and Quality. Publicly funded hospitals sent information through the Internet (CHS Applications website) on knee and hip arthroplasties: patient identification, hospital, joint (hip/knee), type (primary/revision), side of operation, date of surgery and prosthesis (manufacturer's name and reference number). The quality of the data is analysed regularly. We estimate the risk of replacement by the Kaplan-Meier method. Results. A total of 52 hospitals out of 62 send data to RACat, and information on 36,951 knee and 26,477 hip arthroplasties is available. Data quality improved between 2005 and 2010. In 2010 coverage exceeded 70%, with side of operation 97%, and prostheses identification of 80%. The risk of replacement at three years was 3.3% (95% CI:3.1-3.6) for knee, 2.9% (95% CI:2.5-3.3) for total hip, and 2.5% (95% CI:2.0-3.1) for partial hip. Discussion. Risk of replacement is higher than that observed in other registers, although data quality and its improvement over time should be taken into account. Conclusions. The information available in the RACat will help to establish a standard that will enable hospitals to compare results (AU)

Evaluación final voluntaria para médicos residentes de Cirugía Ortopédica y Traumatología: balance de resultados y mirada al futuro / Final voluntary assessment for Traumatology and Orthopaedic Surgery medical residents: a report on the results and a look at the future

Introducción. La conveniencia de establecer una prueba que acredite la formación de los especialistas en Cirugía Ortopédica y Traumatología (COT) al término de su período de formación como médicos internos residentes es objeto de controversia. Con la intención de favorecer y estimular el desarrollo de esta prueba, los actuales vocales de la Comisión Nacional de la Especialidad (CNE) han realizado una revisión de los datos obtenidos en las pasadas ediciones. Material y métodos. Resultados de las pruebas de evaluación voluntaria de final de residencia y de las encuestas de valoración rellenadas por los participantes de la prueba entre los años 2006 y 2011. Resultados. En total han intervenido 231 personas en la evaluación, incrementándose el número de participantes desde 19 en 2005, hasta 71 en 2011. La media de puntuación global a lo largo del período analizado (2006-2011) es de 6,72 puntos. Los no aptos en estos 6 años han sido 9 participantes (4,25%). La media de puntuación en el test es de 7,57 puntos. La puntuación global media de las mesas es de 6,57. Generalidades es la mesa que obtiene peores resultados. La mesa de miembro inferior reconstructivo no ha sido suspendida nunca. La mesa de miembro superior es la que obtiene los mejores resultados medios. Discusión. La prueba está arraigada en la estructura de la formación especializada de la COT en nuestro país. Debemos reconocer favorablemente a aquellos candidatos que optan por presentarse. Este reconocimiento será el mejor estímulo para las futuras promociones (AU)

Introduction. The idea of establishing an examination that accredits the training of the specialists in orthopaedic surgery at the end of their educational period as residents is subject to controversy. With the aim of encouraging the development of this examination, the present members of the National Commission of the Specialty of Orthopaedics (CNE) have reviewed the results obtained in previous examination. Materials and Methods. The results of the voluntary final exam for Orthopaedics residents, and of the surveys of participant opinions for the years 2006 to 2011 are presented. Results. The total number of participants was 231, growing from 19 in 2005, to 71 in 2011. The overall mean score in the period reviewed (2006-2011) was 6.72 out of 10 points. In these 6 years, 9 participants failed (4.25%). The mean score for the test was 7.57. The overall mean score of the oral exam was 6.57. The worst results were obtained in the general knowledge section of the oral examination. Nobody has ever failed the section on reconstruction of the lower extremity. The upper extremity section in the oral examination achieves the best average results. Discussion. The examination has established its place in the structure of orthopaedic resident training in our country, even without making it official by the Administration. We must positively acknowledge those candidates who chose to take the examination and be evaluated by their peers in order to prove their qualification and distinction. This recognition will be the best encouragement for future generations (AU)

[Final voluntary assessment for Traumatology and Orthopaedic Surgery medical residents: a report on the results and a look at the future]. / Evaluación final voluntaria para médicos residentes de Cirugía Ortopédica y Traumatología: balance de resultados y mirada al futuro.

INTRODUCTION: The idea of establishing an examination that accredits the training of the specialists in orthopaedic surgery at the end of their educational period as residents is subject to controversy. With the aim of encouraging the development of this examination, the present members of the National Commission of the Specialty of Orthopaedics (CNE) have reviewed the results obtained in previous examination. MATERIALS AND METHODS: The results of the voluntary final exam for Orthopaedics residents, and of the surveys of participant opinions for the years 2006 to 2011 are presented. RESULTS: The total number of participants was 231, growing from 19 in 2005, to 71 in 2011. The overall mean score in the period reviewed (2006-2011) was 6.72 out of 10 points. In these 6 years, 9 participants failed (4.25%). The mean score for the test was 7.57. The overall mean score of the oral exam was 6.57. The worst results were obtained in the general knowledge section of the oral examination. Nobody has ever failed the section on reconstruction of the lower extremity. The upper extremity section in the oral examination achieves the best average results. DISCUSSION: The examination has established its place in the structure of orthopaedic resident training in our country, even without making it official by the Administration. We must positively acknowledge those candidates who chose to take the examination and be evaluated by their peers in order to prove their qualification and distinction. This recognition will be the best encouragement for future generations.

A prospective randomized study of minimally invasive total knee arthroplasty compared with conventional surgery.

BACKGROUND: Despite intense debate regarding whether minimally invasive techniques for total knee arthroplasty improve clinical outcomes over standard techniques, few prospective randomized trials addressing this debate are available in the literature. We therefore designed this multicenter study to assess the overall safety and effectiveness of a minimally invasive approach without the use of computer navigation in comparison with conventional knee arthroplasty. METHODS: We prospectively randomized 134 patients (101 women and thirty-three men, with an average age of 70.1 years) to undergo surgery for total knee arthroplasty with use of either minimally invasive knee instruments (sixty-six patients) or a standard approach (sixty-eight patients). The follow-up period was one year. RESULTS: On the basis of our sample size, no significant difference was detected between the groups in any of the relevant clinical areas assessed: total range of motion, Knee Society total and function scores, and visual analog scores for pain and activities of daily living. Patients who underwent minimally invasive surgery had a longer mean surgical time (by 5.6 minutes) and had less mean blood loss (by 17 mL). Radiographic measurements demonstrated reliable implant positioning in both groups. Seven patients in each group had an adverse event related to their procedure. CONCLUSIONS: On the basis of the numbers, no significant advantage to minimally invasive total knee arthroplasty over a conventional technique was observed. Greater sample sizes and a longer follow-up period are required to fully determine the long-term safety and efficacy of this minimally invasive surgical technique.

Ética y legislación en la investigación clínica / Ethics and legislation

La investigación desarrolla hipótesis de trabajo que requieren la utilización de pacientes o animales de experimentación. En ocasiones aborda aspectos que pueden tener repercusiones graves para la humanidad. Desde que desarrolló el código de Nurenberg, después de la II guerra mundial, se han establecido controles con leyes, declaraciones, comisiones para reducir los riesgos de todo proyecto científico y de las personas o animales que participan en él (AU)

Research entails working hypotheses requiring the use of test patients or animals. There are times when it broaches aspects that could have serious repercussions for human beings. Since the Nuremberg code was devised after World War II, controls have been put in place by way of laws, declarations, committees to limit the risks of any scientific project and of the people or animals participating in it (AU)

Specialization of midgut cells for synthesis of male isoprenoid pheromone components in two scolytid beetles, Dendroctonus jeffreyi and Ips pini.

Endodermal or midgut cells have only recently been recognized as the site of pheromone synthesis in bark beetles. Midgut cells are not only specialized for digestion, but they have also been recruited to form isoprenoid compounds that function as pheromone components in Ips pini and Dendroctonus jeffreyi. Male bark beetle midgut cells are competent to produce isoprenoid pheromones after feeding or stimulation by juvenile hormone (JH) III. Competent midgut cells share many ultrastructural features with cells that do not secrete isoprenoid pheromone, but they are distinguished from these by abundant and highly ordered arrays of smooth endoplasmic reticula. During secretion, both midgut cells that produce pheromone and cells that do not are characterized by the presence of apical extrusions (apocrine secretion) rather than the presence of vesicles that fuse with the apical membrane and undergo exocytosis (eccrine secretion). Pheromone-producing cells of the midgut do not represent a population of cells that are distinct from cells involved in digestion. All, or most, midgut cells of male I. pini and D. jeffreyi can secrete pheromones as well as digestive enzymes.

Different isoforms of fasciclin II are expressed by a subset of developing olfactory receptor neurons and by olfactory-nerve glial cells during formation of glomeruli in the moth Manduca sexta.

During development of the primary olfactory projection, olfactory receptor axons must sort by odor specificity and seek particular sites in the brain in which to create odor-specific glomeruli. In the moth Manduca sexta, we showed previously that fasciclin II, a cell adhesion molecule in the immunoglobulin superfamily, is expressed by the axons of a subset of olfactory receptor neurons during development and that, in a specialized glia-rich "sorting zone," these axons segregate from nonfasciclin II-expressing axons before entering the neuropil of the glomerular layer. The segregation into fasciclin II-positive fascicles is dependent on the presence of the glial cells in the sorting zone. Here, we explore the expression patterns for different isoforms of Manduca fasciclin II in the developing olfactory system. We find that olfactory receptor axons express transmembrane fasciclin II during the period of axonal ingrowth and glomerulus development. Fascicles of TM-fasciclin II+ axons target certain glomeruli and avoid others, such as the sexually dimorphic glomeruli. These results suggest that TM-fasciclin II may play a role in the sorting and guidance of the axons. GPI-linked forms of fasciclin II are expressed weakly by glial cells associated with the receptor axons before they reach the sorting zone, but not by sorting-zone glia. GPI-fasciclin II may, therefore, be involved in axon-glia interactions related to stabilization of axons in the nerve, but probably not related to sorting.

Premature adrenarche.

Adrenarche is the puberty of the adrenal gland. The descriptive term "pubarche" indicates the appearance of pubic hair, which may be accompanied by axillary hair. This process is considered premature if it occurs before age 8 yr in girls and 9 yr in boys. The chief hormonal products of adrenarche are DHEA and DHEAS. The well-documented evolution of adrenarche in primates and men is incompatible with either a neutral or harmful role for DHEA and implies most likely a positive role for some aspects of young adult pubertal maturation and developmental maturation. Premature adrenarche has no adverse effects on the onset and progression of gonadarche and/or final height. Mechanisms for initiation of adrenal androgen secretion at adrenarche are still not well understood. Maturational increases in 17-hydroxylase and 17,20-lyase are seen together with a lower activity of 3beta-hydroxysteroid dehydrogenase (3beta-HSD). There is good evidence that the zona reticularis is the source of adrenal androgens. Adrenarche and gonadarche are regulated differently. Although premature adrenarche has been thought to be a benign, normal variant of puberty, our findings indicate that, for certain girls, premature adrenarche represents an early clinical feature of syndrome X (obesity, hypertension, dyslipidemia, insulin resistance). Perhaps the early identification of these patients will permit early therapy, such as lifestyle changes, including dietary and activity level intervention. As insulin resistance is an underlying feature of premature adrenarche, it seems rational to assess the efficacy and safety of using insulin-sensitizing agents to treat these individuals. In the absence of controlled longitudinal studies, the cross-sectional data available from our studies suggest that premature pubarche driven by premature adrenarche and hyperinsulinemia may precede the development of ovarian hyperandrogenism, and this sequence may have an early origin with low birth weight serving as a marker. Premature adrenarche may thus be a forerunner of syndrome X in some girls.