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Arctic and alpine tundra ecosystems are large reservoirs of organic carbon1,2. Climate warming may stimulate ecosystem respiration and release carbon into the atmosphere3,4. The magnitude and persistency of this stimulation and the environmental mechanisms that drive its variation remain uncertain5-7. This hampers the accuracy of global land carbon-climate feedback projections7,8. Here we synthesize 136 datasets from 56 open-top chamber in situ warming experiments located at 28 arctic and alpine tundra sites which have been running for less than 1 year up to 25 years. We show that a mean rise of 1.4 °C [confidence interval (CI) 0.9-2.0 °C] in air and 0.4 °C [CI 0.2-0.7 °C] in soil temperature results in an increase in growing season ecosystem respiration by 30% [CI 22-38%] (n = 136). Our findings indicate that the stimulation of ecosystem respiration was due to increases in both plant-related and microbial respiration (n = 9) and continued for at least 25 years (n = 136). The magnitude of the warming effects on respiration was driven by variation in warming-induced changes in local soil conditions, that is, changes in total nitrogen concentration and pH and by context-dependent spatial variation in these conditions, in particular total nitrogen concentration and the carbon:nitrogen ratio. Tundra sites with stronger nitrogen limitations and sites in which warming had stimulated plant and microbial nutrient turnover seemed particularly sensitive in their respiration response to warming. The results highlight the importance of local soil conditions and warming-induced changes therein for future climatic impacts on respiration.
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Respiração Celular , Ecossistema , Aquecimento Global , Tundra , Regiões Árticas , Carbono/metabolismo , Carbono/análise , Ciclo do Carbono , Conjuntos de Dados como Assunto , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Nitrogênio/análise , Plantas/metabolismo , Estações do Ano , Solo/química , Microbiologia do Solo , Temperatura , Fatores de TempoRESUMO
Nitrogen availability is a growth-limiting factor in many habitats1, and the global nitrogen cycle involves prokaryotes and eukaryotes competing for this precious resource. Only some bacteria and archaea can fix elementary nitrogen; all other organisms depend on the assimilation of mineral or organic nitrogen. The nitrogen-rich compound guanidine occurs widely in nature2-4, but its utilization is impeded by pronounced resonance stabilization5, and enzymes catalysing hydrolysis of free guanidine have not been identified. Here we describe the arginase family protein GdmH (Sll1077) from Synechocystis sp. PCC 6803 as a Ni2+-dependent guanidine hydrolase. GdmH is highly specific for free guanidine. Its activity depends on two accessory proteins that load Ni2+ instead of the typical Mn2+ ions into the active site. Crystal structures of GdmH show coordination of the dinuclear metal cluster in a geometry typical for arginase family enzymes and allow modelling of the bound substrate. A unique amino-terminal extension and a tryptophan residue narrow the substrate-binding pocket and identify homologous proteins in further cyanobacteria, several other bacterial taxa and heterokont algae as probable guanidine hydrolases. This broad distribution suggests notable ecological relevance of guanidine hydrolysis in aquatic habitats.
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Hidrolases , Synechocystis , Arginase/metabolismo , Proteínas de Bactérias/metabolismo , Guanidina/metabolismo , Hidrolases/metabolismo , Nitrogênio/metabolismoRESUMO
BACKGROUND: Several reports have described Takotsubo syndrome (TTS) secondary to thyrotoxicosis. A complex interaction of central and peripheral catecholamines with thyroid homeostasis has been suggested. In this study, we analysed sequential thyroid hormone profiles during the acute phase of TTS. METHODS: Thyrotropin (TSH), free T4 (FT4) and free T3 (FT3) concentrations were analysed at predefined time points in 32 patients presenting with TTS or acute coronary syndrome (ACS, n = 16 in each group) in a 2-year period in two German university hospitals. Data were compared to age- and sex-matched controls (10 samples, each of 16 subjects), and an unsupervised machine learning (ML) algorithm identified patterns in the hormone signature. Subjects with thyroid disease and patients receiving amiodarone were excluded from follow-up. RESULTS: Among patients with TTS, FT4 concentrations were significantly higher when compared to controls or ACS. Four subjects (25%) suffered from subclinical or overt thyrotoxicosis. Two additional patients developed subclinical or overt thyrotoxicosis during stay in hospital. In four subjects (25%), FT4 concentrations were increased, despite nonsuppressed TSH concentration, representing an elevated set point of thyroid homeostasis. The thyroid hormone profile was normal in only six patients (38%) presenting with TTS. CONCLUSION: Abnormal thyroid function is frequent in patients with TTS. Primary hyperthyroidism and an elevated set point of thyroid homeostasis are common in TTS, suggesting a stress-dependent endocrine response or type 2 thyroid allostasis. Thyroid function may be a worthwhile target in treating or preventing TTS.
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Cardiomiopatia de Takotsubo/complicações , Cardiomiopatia de Takotsubo/fisiopatologia , Glândula Tireoide/fisiopatologia , Tireotoxicose/complicações , Idoso , Feminino , Homeostase , Humanos , Masculino , Cardiomiopatia de Takotsubo/sangue , Glândula Tireoide/metabolismo , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangueRESUMO
BACKGROUND: The homeostatic euthyroid set point of the hypothalamus-pituitary-thyroid axis of any given individual is unique and oscillates narrowly within substantially broader normal population ranges of circulating free thyroxine (FT4) and thyroid-stimulating hormone (TSH), otherwise termed 'thyroid function test (TFT)'. We developed a mathematical algorithm codenamed Thyroid-SPOT that effectively reconstructs the personalized set point in open-loop situations and evaluated its performance in a retrospective patient sample. METHODS: We computed the set points of 101 patients who underwent total thyroidectomy for non-functioning thyroid disease using Thyroid-SPOT on each patient's own serial post-thyroidectomy TFT. Every predicted set point was compared against its respective healthy pre-operative euthyroid TFT per individual and their separation (i.e. predicted-observed TFT) quantified. RESULTS: Bland-Altman analysis to measure the agreement between each pair of an individual's predicted and actual set points revealed a mean difference in FT4 and TSH of + 3.03 pmol/L (95% CI 2.64, 3.43) and - 0.03 mIU/L (95% CI - 0.25, 0.19), respectively. These differences are small compared to the width of the reference intervals. Thyroid-SPOT can predict the euthyroid set point remarkably well, especially for TSH with a 10-16-fold spread in magnitude between population normal limits. CONCLUSION: Every individual's equilibrium euthyroid set point is unique. Thyroid-SPOT serves as an accurate, precise and reliable targeting system for optimal personalized restoration of euthyroidism. This algorithm can guide clinicians in L-thyroxine dose titrations to resolve persistent dysthyroid symptoms among challenging cases harbouring "normal TFT" within the laboratory ranges but differing significantly from their actual euthyroid set points.
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Doenças da Glândula Tireoide/cirurgia , Glândula Tireoide , Tireoidectomia , Hormônio Liberador de Tireotropina/sangue , Tireotropina/sangue , Tiroxina , Algoritmos , Cálculos da Dosagem de Medicamento , Feminino , Terapia de Reposição Hormonal/métodos , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Valores de Referência , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/fisiopatologia , Testes de Função Tireóidea/métodos , Glândula Tireoide/metabolismo , Glândula Tireoide/cirurgia , Tireoidectomia/efeitos adversos , Tireoidectomia/métodos , Tiroxina/sangue , Tiroxina/farmacologiaRESUMO
Despite glyphosate's wide use for weed control in agriculture, questions remain about the herbicide's effect on soil microbial communities. The existing scientific literature contains conflicting results, from no observable effect of glyphosate to the enrichment of agricultural pathogens such as Fusarium spp. We conducted a comprehensive field-based study to compare the microbial communities on the roots of plants that received a foliar application of glyphosate to adjacent plants that did not. The 2-year study was conducted in Beltsville, MD, and Stoneville, MS, with corn and soybean crops grown in a variety of organic and conventional farming systems. By sequencing environmental metabarcode amplicons, the prokaryotic and fungal communities were described, along with chemical and physical properties of the soil. Sections of corn and soybean roots were plated to screen for the presence of plant pathogens. Geography, farming system, and season were significant factors determining the composition of fungal and prokaryotic communities. Plots treated with glyphosate did not differ from untreated plots in overall microbial community composition after controlling for other factors. We did not detect an effect of glyphosate treatment on the relative abundance of organisms such as Fusarium spp.IMPORTANCE Increasing the efficiency of food production systems while reducing negative environmental effects remains a key societal challenge to successfully meet the needs of a growing global population. The herbicide glyphosate has become a nearly ubiquitous component of agricultural production across the globe, enabling an increasing adoption of no-till agriculture. Despite this widespread use, there remains considerable debate on the consequences of glyphosate exposure. In this paper, we examine the effect of glyphosate on soil microbial communities associated with the roots of glyphosate-resistant crops. Using metabarcoding techniques, we evaluated prokaryotic and fungal communities from agricultural soil samples (n = 768). No effects of glyphosate were found on soil microbial communities associated with glyphosate-resistant corn and soybean varieties across diverse farming systems.
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Bactérias/isolamento & purificação , Fungos/isolamento & purificação , Glicina/análogos & derivados , Herbicidas/administração & dosagem , Microbiota , Raízes de Plantas/microbiologia , Microbiologia do Solo , Glicina/administração & dosagem , Maryland , Microbiota/efeitos dos fármacos , Mississippi , Micobioma , Glycine max/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , GlifosatoRESUMO
In recent years, many γ-ray sources have been identified, yet the unresolved component hosts valuable information on the faintest emission. In order to extract it, a cross-correlation with gravitational tracers of matter in the Universe has been shown to be a promising tool. We report here the first identification of a cross-correlation signal between γ rays and the distribution of mass in the Universe probed by weak gravitational lensing. We use data from the Dark Energy Survey Y1 weak lensing data and the Fermi Large Area Telescope 9-yr γ-ray data, obtaining a signal-to-noise ratio of 5.3. The signal is mostly localized at small angular scales and high γ-ray energies, with a hint of correlation at extended separation. Blazar emission is likely the origin of the small-scale effect. We investigate implications of the large-scale component in terms of astrophysical sources and particle dark matter emission.
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The combination of multiple observational probes has long been advocated as a powerful technique to constrain cosmological parameters, in particular dark energy. The Dark Energy Survey has measured 207 spectroscopically confirmed type Ia supernova light curves, the baryon acoustic oscillation feature, weak gravitational lensing, and galaxy clustering. Here we present combined results from these probes, deriving constraints on the equation of state, w, of dark energy and its energy density in the Universe. Independently of other experiments, such as those that measure the cosmic microwave background, the probes from this single photometric survey rule out a Universe with no dark energy, finding w=-0.80_{-0.11}^{+0.09}. The geometry is shown to be consistent with a spatially flat Universe, and we obtain a constraint on the baryon density of Ω_{b}=0.069_{-0.012}^{+0.009} that is independent of early Universe measurements. These results demonstrate the potential power of large multiprobe photometric surveys and pave the way for order of magnitude advances in our constraints on properties of dark energy and cosmology over the next decade.
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We report the first detection of gravitational lensing due to galaxy clusters using only the polarization of the cosmic microwave background (CMB). The lensing signal is obtained using a new estimator that extracts the lensing dipole signature from stacked images formed by rotating the cluster-centered Stokes QU map cutouts along the direction of the locally measured background CMB polarization gradient. Using data from the SPTpol 500 deg^{2} survey at the locations of roughly 18 000 clusters with richness λ≥10 from the Dark Energy Survey (DES) Year-3 full galaxy cluster catalog, we detect lensing at 4.8σ. The mean stacked mass of the selected sample is found to be (1.43±0.40)×10^{14}M_{â} which is in good agreement with optical weak lensing based estimates using DES data and CMB-lensing based estimates using SPTpol temperature data. This measurement is a key first step for cluster cosmology with future low-noise CMB surveys, like CMB-S4, for which CMB polarization will be the primary channel for cluster lensing measurements.
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INTRODUCTION: Due to lack of patient/health care provider awareness causing delayed diagnosis, the bleeding phenotype and provider interventions in adolescents with heavy menstrual bleeding (HMB) and bleeding disorders (BD) may be different when compared to adults. AIM: The aim of this study was to compare/characterize bleeding phenotype and provider interventions in postmenarchal adolescents < 18 years and premenopausal adults ≥ 18 years with HMB and BD. METHODS: Patient demographics, BD, and provider interventions/therapy details for HMB were compared between both age groups enrolled in the Centers for Disease Control and Prevention (CDC) Female Universal Data Collection (UDC) surveillance project in United States hemophilia treatment centres. Cross-sectional descriptive analyses including frequency distributions, summary statistics, bivariate and logistic regression analyses were performed. RESULTS: Of 269 females (79 adolescents; median age 16 years, interquartile range (IQR) = 2; 190 adults; median age 27 years, IQR = 13) evaluated, BD distribution was similar in both groups. Compared to adolescents, adults more often had family history of bleeding (Adjusted odds ratios [AOR] = 2.6, 1.3-5.6), delay in diagnosis (AOR = 2.5, 1.2-4.9), bleeding with dental procedures (AOR = 2.0, 1.0-4.0), gastrointestinal bleeding (AOR = 4.6, 1.0-21.9), anaemia (AOR = 2.7, 1.4-5.2), utilized desmopressin less often (AOR = 0.4, 0.2-0.8) and underwent gynaecologic procedure/surgery more frequently (AOR = 5.9, 1.3-27.3). CONCLUSION: Bleeding phenotypes of adolescents and adults with HMB and BD were different with more frequent bleeding complications, anaemia, gynaecologic procedures/surgeries, less desmopressin use and more delay in diagnosing BD in adults. Longitudinal studies are needed to determine whether improved patient/provider awareness and education will translate to early diagnosis and timely management of BD/HMB in adolescents that may prevent/reduce future haematologic/gynaecologic complications.
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Transtornos da Coagulação Sanguínea/diagnóstico , Menorragia/diagnóstico , Adolescente , Adulto , Anemia/etiologia , Antifibrinolíticos/uso terapêutico , Transtornos da Coagulação Sanguínea/complicações , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Estudos Transversais , Desamino Arginina Vasopressina/uso terapêutico , Diagnóstico Tardio , Feminino , Hemorragia Gastrointestinal/etiologia , Hemostáticos/uso terapêutico , Humanos , Modelos Logísticos , Menopausa , Menorragia/complicações , Menorragia/tratamento farmacológico , Menorragia/etnologia , Razão de Chances , Fenótipo , Adulto JovemRESUMO
Loss-of-function variants in the MC1R gene cause recessive red or yellow coat-colour phenotypes in many species. The canine MC1R:c.916C>T (p.Arg306Ter) variant is widespread and found in a homozygous state in many uniformly yellow- or red-coloured dogs. We investigated cream-coloured Australian Cattle Dogs whose coat colour could not be explained by this variant. A genome-wide association study with 10 cream and 123 red Australian Cattle Dogs confirmed that the cream locus indeed maps to MC1R. Whole-genome sequencing of cream dogs revealed a single nucleotide variant within the MITF binding site of the canine MC1R promoter. We propose to designate the mutant alleles at MC1R:c.916C>T as e1 and at the new promoter variant as e2 . Both alleles segregate in the Australian Cattle Dog breed. When we considered both alleles in combination, we observed perfect association between the MC1R genotypes and the cream coat colour phenotype in a cohort of 10 cases and 324 control dogs. Analysis of the MC1R transcript levels in an e1 /e2 compound heterozygous dog confirmed that the transcript levels of the e2 allele were markedly reduced with respect to the e1 allele. We further report another MC1R loss-of-function allele in Alaskan and Siberian Huskies caused by a 2-bp deletion in the coding sequence, MC1R:c.816_817delCT. We propose to term this allele e3 . Huskies that carry two copies of MC1R loss-of-function alleles have a white coat colour.
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Cães/genética , Cor de Cabelo/genética , Receptor Tipo 1 de Melanocortina/genética , Alelos , Animais , Austrália , Cruzamento , Estudos de Associação Genética/veterinária , Genótipo , Fenótipo , Regiões Promotoras Genéticas , Análise de Sequência de DNARESUMO
The treatment of esophageal atresia is not centralized in Germany. Therefore, high numbers of departments are involved. Data on the results of esophageal atresia repair from Germany are lacking. The aim of this study was to evaluate the early postoperative results after repair of esophageal atresia based on unbiased data of a German health insurance. We aimed to determine whether characteristics of the departments had an impact on outcome and compared the results from this study with the literature data from centers with a high caseload. Data of a German health insurance covering â¼10% of the population were analyzed. All patients who had undergone esophageal atresia repair from January 2007 to August 2012 were included. Follow-up data of 1 year postoperatively were analyzed. The potential impact of various characteristics of the treating surgical institutions was assessed. Results were compared with the latest international literature. Seventy-five patients with esophageal atresia underwent reconstructive surgery in 37 departments. The incidences of anastomotic leak (3%) and recurrent tracheoesophageal fistula (7%) were comparable with the literature (both 2-8%). Anastomotic stricture required dilatation in 57% of patients (mean 5.1 ± 5.6 dilatations) comparing unfavorably to most, but not all international reports. During 1-year follow-up, 93% of the patients were readmitted at least once (mean 3.9 ± 3.1 admissions). The incidence of complications did not correlate with any of the characteristics of the treating institutions such as academic affiliation, the number of consultants, beds, and preterm infants treated per year (all P > 0.05). Based on unbiased data, postoperative results after repair of esophageal atresia in Germany are comparable with recently published reports from international single centers. A correlation between the complication rate and characteristics of the treating institutions was not identified.
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Anastomose Cirúrgica/efeitos adversos , Atresia Esofágica/cirurgia , Esofagoplastia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Anastomose Cirúrgica/métodos , Fístula Anastomótica/epidemiologia , Fístula Anastomótica/etiologia , Pré-Escolar , Bases de Dados Factuais , Estenose Esofágica/epidemiologia , Estenose Esofágica/etiologia , Estenose Esofágica/cirurgia , Esofagoplastia/métodos , Esôfago/cirurgia , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Seguro Saúde/estatística & dados numéricos , Masculino , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Fístula Traqueoesofágica/epidemiologia , Fístula Traqueoesofágica/etiologiaRESUMO
We present a mass map reconstructed from weak gravitational lensing shear measurements over 139 deg2 from the Dark Energy Survey science verification data. The mass map probes both luminous and dark matter, thus providing a tool for studying cosmology. We find good agreement between the mass map and the distribution of massive galaxy clusters identified using a red-sequence cluster finder. Potential candidates for superclusters and voids are identified using these maps. We measure the cross-correlation between the mass map and a magnitude-limited foreground galaxy sample and find a detection at the 6.8σ level with 20 arc min smoothing. These measurements are consistent with simulated galaxy catalogs based on N-body simulations from a cold dark matter model with a cosmological constant. This suggests low systematics uncertainties in the map. We summarize our key findings in this Letter; the detailed methodology and tests for systematics are presented in a companion paper.
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The incidence and prevalence of conditions of the reproductive tract varies. This is related to both the complexity and spectrum of underlying and associated conditions. In some cases, only retrospective or case data are available, and likely under-reporting occurs, contributing to a lower than expected prevalence. Given the complex nature in which the reproductive tract develops in the fetus, it is important to understand the embryology, especially in situations of congenital anatomic differences. It is interesting to note not only patterns of conditions, but patterns of concurrent conditions or anomalies such as those occurring with isolated Müllerian anomalies, in conjunction with disorders of sexual differentiation or with cloacal malformations. This review will address typical presentation of these conditions, highlights of management and point to areas of research need, including clinical outcomes and genetic implications.
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Anormalidades Congênitas/patologia , Transtornos do Desenvolvimento Sexual/patologia , Genitália Feminina/anormalidades , Ductos Paramesonéfricos/anormalidades , Feminino , HumanosRESUMO
The objective of the study was to evaluate the roles of central and peripheral T3 regulation. In a prospective study involving 1,796 patients, the equilibria between FT3 and TSH were compared in untreated and L-T4-treated patients with varying functional states, residual thyroid secretory capacities and magnitudes of TSH stimulation. T3 concentrations were stable over wide variations in TSH levels (from 0.2 to 7 mU/l) and endogenous T4 production in untreated patients, but unbalanced in L-T4-treated athyreotic patients where T3 correlated with exogenous T4 supply. T3 stability was related to TSH-stimulated deiodinase activity by clinical observation, as predicted by theoretical modelling. Deiodinase activity in treated patients was reduced due to both diminished responsiveness to TSH and lack of thyroidal capacity. Deiodinase activity was increased in high thyroid volume, compared to lower volumes in euthyroid patients (<5 ml, p<0.001). While deiodinase differed between euthyroid and subclinically hypothyroid patients in high volume, 26.7 nmol/s (23.6, 29.2), n=214 vs. 28.9 nmol/s (26.7, 31.5), n=20, p=0.02, it was equivalent between the 2 functional groups in low volume, 23.3 nmol/s (21.3, 26.1), n=117 vs. 24.6 nmol/s (22.2, 27.5), n=38, p=0.22. These findings suggest that the thyroid gland and peripheral tissues are integrated in the physiological process of T3 homeostasis in humans via a feed-forward TSH motif, which coordinates peripheral and central regulatory mechanisms. Regulatory and capacity deficiencies collectively impair T3 homeostasis in L-T4-treated patients.
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Homeostase/fisiologia , Iodeto Peroxidase/metabolismo , Tireotropina/metabolismo , Tiroxina/efeitos adversos , Tiroxina/metabolismo , Tri-Iodotironina/metabolismo , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
Graves' disease is caused by stimulating autoantibodies against the thyrotropin receptor inducing uncontrolled overproduction of thyroid hormones. A Bridge Assay is presented for direct detection of these thyroid-stimulating immunoglobulins using thyrotropin receptor chimeras. A capture receptor, formed by replacing aa residues 261-370 of the human thyrotropin receptor with residues 261-329 from rat lutropin/choriogonadotropin receptor and fixed to microtiter plates, binds one arm of the autoantibody. The second arm bridges to the signal receptor constructed from thyrotropin receptor (aa 21-261) and secretory alkaline phosphatase (aa 1-519) inducing chemiluminescence. The working range of the assay is from 0.3 IU/l to 50 IU/l with a cutoff of 0.54 IU/l and functional sensitivity of 0.3 IU/l. Sensitivity and specificity are 99.8 and 99.1%, respectively, with a diagnostic accuracy of 0.998. The low grey zone is from 0.3-0.54 IU/l. The stimulatory character of the assayed antibodies is shown through a good correlation (r=0.7079, p<10(-7)) to serum T4 levels of untreated patients. In Graves' disease, titers are increased in associated eye disease. In 3 hypothyroid patients with sera positive in the thyrotropin receptor competition assay and in the blocking bioassay, antibodies are not detected by the Bridge Assay, while the monoclonal blocking antibody K1-70 was detected. In Hashimoto disease thyrotropin receptor autoantibodies are detected in some patients, but not in goiter. This Bridge Assay delivers good diagnostic accuracy for identification of Graves' disease patients. Its high sensitivity may facilitate early detection of onset, remission, or recurrence of Graves' disease enabling timely adaption of the treatment.Human genes: TSHR, Homo sapiens, acc. no. M31774.1.
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Autoanticorpos/análise , Doença de Graves/etiologia , Receptores da Tireotropina/imunologia , Autoanticorpos/imunologia , Quimera , Humanos , Sensibilidade e Especificidade , Tiroxina/sangueRESUMO
Platelet function defects (PFD) are reported to occur frequently in adult women with heavy menstrual bleeding (HMB). Few studies on adolescent HMB report varying incidence rates (2-44%) for PFD. We reviewed our institutional experience in detecting and managing PFD in adolescent HMB. Postmenarchial girls and adolescents with HMB seen at our institution undergo a comprehensive bleeding disorder work-up by paediatric haematology and paediatric gynaecology providers. Whole blood platelet aggregometry (WBPA) is performed as a second tier test after excluding thrombocytopaenia, coagulation factor deficiencies and Von Willebrand disease (VWD). We retrospectively reviewed the medical records of adolescents with HMB seen between June 2009 and November 2010, as approved by the Institutional Review Board. Patient demographics, clinical features, laboratory results, therapy details and patient outcome information were analysed. Overall, 114 postmenarchial girls and adolescents with HMB were evaluated; 68 patients (59%) had WBPA study performed. Nineteen patients (28%) had at least one aggregation or secretion defect; 12 (18%) had two or more such defects. Treatment included hormonal therapy (13/19; 68%), antifibrinolytic agents (8/19; 42%) and intra-nasal DDAVP (3/19; 16%). Thirteen patients (81%) had improved outcome (median follow-up--15.6 months; range of 1-66 months). In this study, PFD were identified in nearly one-third of girls with HMB, with the majority of these having two or more defects as identified by WBPA. Further prospective studies are needed to better define the prevalence and address appropriate management of HMB and other bleeding complications of PFD in adolescents.
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Plaquetas/metabolismo , Menorragia/etiologia , Adolescente , Adulto , Antifibrinolíticos/uso terapêutico , Plaquetas/efeitos dos fármacos , Criança , Desamino Arginina Vasopressina/uso terapêutico , Feminino , Humanos , Menorragia/diagnóstico , Menorragia/tratamento farmacológico , Agregação Plaquetária/efeitos dos fármacos , Testes de Função Plaquetária , Estudos Retrospectivos , Adulto JovemRESUMO
Exon 28 polymorphism p.D1472H is associated with significantly lower von Willebrand Ristocetin cofactor activity (VWF:RCoF) to von Willebrand antigen (VWF:Ag) ratio compared to normal, but has been reported as not conferring haemorrhagic risk. The impact of this polymorphism while assessing symptomatic patients for von Willebrand disease (VWD) has not been previously analysed. We retrospectively reviewed charts of children with clinically significant bleeding and abnormal VW panel who underwent VW exon 28 analysis. Twenty-three of 63 patients studied had p.D1472H. Of these 23 patients, 6 with borderline low VWF:RCo were given provisional diagnosis of VWD type 1 by treating physicians, which could be alternatively explained as due to the effect of p.D1472H. None of the patients with low VWF:RCo, decreased VWF:RCo/VWF:Ag ratio and p.D1472H had VWD type 2M mutations identified. This study illustrates the challenge in diagnosing VWD using ristocetin-based VW assay in symptomatic patients with p.D1472H.
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Éxons , Hemorragia/genética , Doenças de von Willebrand/diagnóstico , Doenças de von Willebrand/genética , Fator de von Willebrand/genética , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Fenótipo , Polimorfismo Genético , Estudos RetrospectivosRESUMO
UNLABELLED: The refeeding syndrome is a dangerous condition, which may even lead to death. The syndrome occurs after re-establishment of adequate nutrition in malnourished and cachectic patients. More specifically its occurrence has been reported during oral, enteral and parenteral feeding. Early diagnosis is crucial for adequate and timely therapy. However, due to a lack of knowledge in the community this is not always achieved. The leading symptom is hypophosphatemia, often accompanied by electrolyte disturbances and vitamin and trace element deficiencies. Due to a concomitant administration of carbohydrates and intravenous fluid volume it may also lead to hypervolemia with cardiac failure. Compromise of other organ functions with a varying degree of severity, even leading to death, have been reported. The most efficient prevention of the refeeding syndrom is recommended by an early identification of patients at risk and the administration of an initially lower caloric nutrition accompanied by a tight and regularly scheduled observation of relevant laboratory parameters. METHODS: This literature research included the following terms: "refeeding syndrome" and "hypophosphataemia" including the 2006 guidelines from the National Institute for Health and Clinical Excellence (UK).
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Deficiência de Vitaminas/prevenção & controle , Insuficiência Cardíaca/prevenção & controle , Hipofosfatemia/prevenção & controle , Insuficiência de Múltiplos Órgãos/prevenção & controle , Síndrome da Realimentação/diagnóstico , Síndrome da Realimentação/prevenção & controle , Desequilíbrio Hidroeletrolítico/prevenção & controle , Deficiência de Vitaminas/diagnóstico , Cuidados Críticos/métodos , Insuficiência Cardíaca/diagnóstico , Humanos , Hipofosfatemia/diagnóstico , Insuficiência de Múltiplos Órgãos/diagnóstico , Desequilíbrio Hidroeletrolítico/diagnósticoRESUMO
We report about a thirty-five-year-old male patient with miliary TB as first manifestation of HIV-infection.