34 research outputs found

    Could giardiasis be a risk factor for low zinc status in schoolchildren from northwestern Mexico? A cross-sectional study with longitudinal follow-up

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    <p>Abstract</p> <p>Background</p> <p>Both giardiasis and zinc deficiency are serious health problems worldwide. In Mexico, the prevalence of <it>G. intestinalis </it>was estimated at 32% in 1994. It remains a health problem in northwestern Mexico. Recent surveys (1987, 1995, and 1999) reported zinc deficiency in the Mexican population. The association of giardiasis and malabsorption of micronutrients has been well documented, although the association with zinc remains controversial. This study investigated the association between giardiasis and zinc deficiency in schoolchildren from northwestern Mexico.</p> <p>Methods</p> <p>We combined a cross-sectional design with a longitudinal follow-up six months after parasite treatment. The baseline sample consisted of 114 schoolchildren (mean age 8.8 yr) from seven suburban public schools, grouped as <it>Giardia</it>-free (<it>n </it>= 65, 57%) and <it>Giardia</it>-infected (<it>n </it>= 49, 43%). Three stool analyses per child were done using Faust's method. Children with giardiasis received secnidazole. Serum zinc was determined by atomic absorption spectrophotometry. Height and weight were measured. Socioeconomic information was obtained in an oral questionnaire, and daily zinc intake was assessed using 24 hour-recalls. Pearson's correlation and ANCOVA and paired t-test analyses were used to determine the association between giardiasis and zinc status.</p> <p>Results</p> <p>Longitudinal analysis demonstrated a significant increase of the mean serum zinc levels in the <it>Giardia</it>-infected group six months after treatment (13.78 vs. 19.24 μmol/L μmol/L; p = 0.001), although no difference was found between the <it>Giardia</it>-free and the <it>Giardia</it>-infected groups (p = 0.86) in the baseline analysis. Z scores for W/A and H/A were lower in the <it>Giardia</it>-infected than in the <it>Giardia</it>-free group (p < 0.05). No difference was observed in the socioeconomic characteristics and mean daily intakes of zinc between the groups (p > 0.05).</p> <p>Conclusions</p> <p>Giardiasis may be a risk factor for zinc deficiency in schoolchildren from northwestern Mexico.</p

    The Evolution of Compact Binary Star Systems

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    We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and BHs are thought to be the primary astrophysical sources of gravitational waves (GWs) within the frequency band of ground-based detectors, while compact binaries of WDs are important sources of GWs at lower frequencies to be covered by space interferometers (LISA). Major uncertainties in the current understanding of properties of NSs and BHs most relevant to the GW studies are discussed, including the treatment of the natal kicks which compact stellar remnants acquire during the core collapse of massive stars and the common envelope phase of binary evolution. We discuss the coalescence rates of binary NSs and BHs and prospects for their detections, the formation and evolution of binary WDs and their observational manifestations. Special attention is given to AM CVn-stars -- compact binaries in which the Roche lobe is filled by another WD or a low-mass partially degenerate helium-star, as these stars are thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure

    Polycystic ovary syndrome: a complex condition with psychological, reproductive and metabolic manifestations that impacts on health across the lifespan

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    Polycystic ovary syndrome (PCOS) is of clinical and public health importance as it is very common, affecting up to one in five women of reproductive age. It has significant and diverse clinical implications including reproductive (infertility, hyperandrogenism, hirsutism), metabolic (insulin resistance, impaired glucose tolerance, type 2 diabetes mellitus, adverse cardiovascular risk profiles) and psychological features (increased anxiety, depression and worsened quality of life). Polycystic ovary syndrome is a heterogeneous condition and, as such, clinical and research agendas are broad and involve many disciplines. The phenotype varies widely depending on life stage, genotype, ethnicity and environmental factors including lifestyle and bodyweight. Importantly, PCOS has unique interactions with the ever increasing obesity prevalence worldwide as obesity-induced insulin resistance significantly exacerbates all the features of PCOS. Furthermore, it has clinical implications across the lifespan and is relevant to related family members with an increased risk for metabolic conditions reported in first-degree relatives. Therapy should focus on both the short and long-term reproductive, metabolic and psychological features. Given the aetiological role of insulin resistance and the impact of obesity on both hyperinsulinaemia and hyperandrogenism, multidisciplinary lifestyle improvement aimed at normalising insulin resistance, improving androgen status and aiding weight management is recognised as a crucial initial treatment strategy. Modest weight loss of 5% to 10% of initial body weight has been demonstrated to improve many of the features of PCOS. Management should focus on support, education, addressing psychological factors and strongly emphasising healthy lifestyle with targeted medical therapy as required. Monitoring and management of long-term metabolic complications is also an important part of routine clinical care. Comprehensive evidence-based guidelines are needed to aid early diagnosis, appropriate investigation, regular screening and treatment of this common condition. Whilst reproductive features of PCOS are well recognised and are covered here, this review focuses primarily on the less appreciated cardiometabolic and psychological features of PCOS

    The Biochemistry, Ultrastructure, and Subunit Assembly Mechanism of AMPA Receptors

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    The AMPA-type ionotropic glutamate receptors (AMPA-Rs) are tetrameric ligand-gated ion channels that play crucial roles in synaptic transmission and plasticity. Our knowledge about the ultrastructure and subunit assembly mechanisms of intact AMPA-Rs was very limited. However, the new studies using single particle EM and X-ray crystallography are revealing important insights. For example, the tetrameric crystal structure of the GluA2cryst construct provided the atomic view of the intact receptor. In addition, the single particle EM structures of the subunit assembly intermediates revealed the conformational requirement for the dimer-to-tetramer transition during the maturation of AMPA-Rs. These new data in the field provide new models and interpretations. In the brain, the native AMPA-R complexes contain auxiliary subunits that influence subunit assembly, gating, and trafficking of the AMPA-Rs. Understanding the mechanisms of the auxiliary subunits will become increasingly important to precisely describe the function of AMPA-Rs in the brain. The AMPA-R proteomics studies continuously reveal a previously unexpected degree of molecular heterogeneity of the complex. Because the AMPA-Rs are important drug targets for treating various neurological and psychiatric diseases, it is likely that these new native complexes will require detailed mechanistic analysis in the future. The current ultrastructural data on the receptors and the receptor-expressing stable cell lines that were developed during the course of these studies are useful resources for high throughput drug screening and further drug designing. Moreover, we are getting closer to understanding the precise mechanisms of AMPA-R-mediated synaptic plasticity

    ONE-STAGE TREATMENT OF CONGENITAL DISLOCATION OF THE HIP IN OLDER CHILDREN

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    We reviewed the results of a primary one-stage combined operation in 47 patients (55 hips) who were greater than or equal to 4 years and had congenital dislocation of the hip. At a mean follow-up of 7.5 years (2-16 years), 67% of the whole series had good or excellent clinical results, and 65% were good or excellent radiologically. Avascular necrosis occurred in four patients, and redislocation also occurred in four patients. We concluded that most of the children who are greater than or equal to 4 years and who have congenital dislocation of the hip can successfully be treated with an extensive one-stage operation consisting of open reduction combined with innominate osteotomy and femoral varus, derotation, and shortening osteotomy. We reviewed the results of a primary one-stage combined operation in 47 patients (55 hips) who were greater than or equal to 4 years and had congenital dislocation of the hip. At a mean follow-up of 7.5 years (2-16 years), 67% of the whole series had good or excellent clinical results, and 65% were good or excellent radiologically. Avascular necrosis occurred in four patients, and redislocation also occurred in four patients. We concluded that most of the children who are greater than or equal to 4 years and who have congenital dislocation of the hip can successfully be treated with an extensive one-stage operation consisting of open reduction combined with innominate osteotomy and femoral varus, derotation, and shortening osteotomy.</p

    Traumatic dislocation and fracture-dislocation of the hip: A long-term follow-up study

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    Objective: Traumatic dislocation and fracture-dislocation of the hip is an absolute orthopedic emergency that is steadily increasing in incidence. Early recognition and prompt, stable reduction is the essence of successful management. A delay in recognition and reduction leads to preventable complications and morbidity. The purpose of this retrospective study is to identify prognostic factors that predict long-term outcome after hip dislocation

    Surgical treatment of the congenital dislocation of the hip after walking age: open reduction and Salter's osteotomy Tratamento cirúrgico da luxação congênita do quadril pós marcha: redução aberta e osteotomia de Salter

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    The congenital dislocation of the hip, after the function of weight bearing begins or walking phase requires surgical treatment, and one of the options is the open reduction combined to innominate osteotomy (Salter). In this study, the results of 18 patients, 22 surgically treated hips with congenital dislocation, were evaluated from 1989 and 1995, using innominate osteotomy, by Salter's technique after open reduction. The age of the patients at the time of surgery ranged from 12 to 30 months (age after march), mean age of 19 months. Fifteen were female and 3 were male, 4 patients had bilateral dislocation and in the remaining, 8 had their left hip dislocated and 6 had their right hip dislocated. The results were evaluated according to Dutoit et al.(3) clinical criteria and to Severin(12) radiological criteria, after a mean follow-up of 48 months. Eighteen percent of excellent clinical results (4); 54% of good results (12); 14% of regular results (3) and 14% of bad results(3) were obtained. As to the radiologic criteria, 36% of the hips were classified as excellent (8); 45% as good (10); 5% regular (1) and 14% bad (3). There were 3 cases of re-dislocation which were treated by a different surgical technique. No cases of infection, graft fracture and vascular or nervous injury were reported.<br>A luxação congênita do quadril (LCQ), após a marcha, requer o tratamento cirúrgico, sendo uma das opções a redução aberta associada a osteotomia do osso inominado (tipo Salter). Neste estudo foram avaliados 18 pacientes, 22 quadris, que apresentavam LCQ tratados cirurgicamente, entre 1989 e 1995, utilizando a osteotomia do osso inominado, pela técnica de Salter, pós redução aberta. A idade dos pacientes, na época da cirurgia, variou de 12 a 30 meses, com média de 19 meses, sendo 15 do sexo feminino e 3 do masculino, 4 pacientes tinham acometimento bilateral, sendo que nos demais, 8 tinham o quadril esquerdo acometido e 6 o lado direito. Os resultados foram avaliados segundo critérios clínicos de Dutoit et al.(3) e radiográficos de Severin(12), após um seguimento médio de 48 meses. Clinicamente foram obtidos 18% de resultados excelentes (4); 54% resultados bons (12); 14% regulares (3); e 14% ruins (3). Quanto aos critérios radiográficos, encontramos 36% dos quadris classificados como excelentes (8); 45% bons (10); 5% regulares (1); e 14% ruins(3). Como complicações foram constatados 3 casos de reluxação, tratados com outra técnica cirúrgica. Não foi observado nenhum caso de infecção, fratura do enxerto e lesão vascular ou nervosa
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