Hipotireoidismo na espécie canina: avaliação da ultra-sonografia cervical como metodologia diagnóstica

The aim of this study is to evaluate cervical ultrasonography as methods for diagnosis of hypothyroidism. Twenty dogs were distributed in 2 groups: 10 dogs with hypothyroidism, and 10 healthy dogs as a control group. All dogs were submitted to ultrasonographic examination in the cervical area. To confirm hypothyroidism diagnosis, total T4, free T4 and TSH hormones samples were obtained and, also, cholestherol and triglycerides. Hypothyroid animals submitted to cervical ultrasonography showed marked reduction in the total volume of the thyroid gland, with statistical significance (p<0,05), in comparison to normal dogs. This alteration demonstrated the gland atrophy secondary to hypothyroidism.O objetivo do presente estudo foi avaliar a ultra-sonografia das glândulas tireóides em animais com hipotireoidismo primário. Foram utilizados dez cães hipotireoideos, diagnosticados, através de anamnese, exame físico e exames laboratoriais, tais como dosagens séricas de T4 total, T4 livre, TSH, colesterol e triglicérides; e 10 cães eutireoideos A ultra-sonografia cervical revelou nítida redução do volume total da glândula tireóide em todos os animais hipotireoideos, estatisticamente significante (p<0,05), em comparação aos animais considerados eutireoideos, denotando, assim, a existência de atrofia glandular, secundária ao hipotireoidismo

An activating mutation in the CRHR1 gene is rarely associated with pituitary-dependent hyperadrenocorticism in poodles

OBJECTIVES: Pituitary-dependent hyperadrenocorticism is the most common cause of naturally occurring hypercortisolism in dogs. CRHR1 expression in human and dog corticotrophinomas suggested that this gene affects pituitary tumorigenesis. The present study aimed to investigate mutations in the CRHR1 coding region in poodles with pituitary-dependent hyperadrenocorticism. METHODS: Fifty poodles with pituitary-dependent hyperadrenocorticism and 50 healthy poodles were studied. Genomic DNA was amplified by PCR and analyzed by Sanger sequencing. RESULTS: The novel CRHR1 p.V97M mutation was identified in one dog. This valine residue, located in the amino-terminal extracellular domain, exhibits high affinity for its corticotropin-releasing hormone (CRH) ligand. Bioinformatic analysis revealed structural rearrangements in the mutant protein, with a 17% increase in the surface binding affinity between CRHR1 and CRH. In vitro functional studies showed that mutant CRHR1 induced higher ACTH secretion than the wild type after stimulation with human CRH. CONCLUSION: These results suggest that germline activating mutations in CRHR1 may be a rare cause of pituitary hyperadrenocorticism in poodles

Análise de mutação germinativa do Tpit em cães da raça Poodle com hiperadrenocorticismo ACTH-dependente

There is a high incidence of pituitary-dependent hyperadrenocorticism (PDH) in Poodle dogs, with family members being affected by the disease, suggesting a genetic involvement. Tpit is an obligate transcription factor for the expression of pro-opiomelanocortingene and for corticotroph terminal differentiation. The aim of the present study was to screen the Tpit gene for germline mutations in Poodles with PDH. Fifty Poodle dogs (33 female, 8.71 +/- 2.8 years) with PDH and 50 healthy Poodle dogs (32 females, 9.4241 2.8 years) were studied. Genomic DNA was isolated from peripheral blood, amplified by PCR and submitted to automatic sequence. No mutation in the coding region of Tpit was found, whereas the new single nucleotide polymorphism p.S343G, in heterozygous state, was found in the same frequency in both PDH and control groups. We concluded that Tpit gain-of-function mutations are not involved in the etiology of PDH in Poodle dogs.O hiperadrenocorticismo ACTH-dependente (HACAD) apresenta elevada incidência em cães da raça Poodle, sendo que membros da mesma família têm sido acometidos pela doença, sugerindo envolvimento genético. Tpit é um fator de transcrição obrigatório para a expressão do gene da pro-opiomelanocortina e para a diferenciação terminal dos corticotrofos. O objetivo deste trabalho foi pesquisar mutações germinativas no gene Tpit em Poodles com HACAD. Cinquenta cães da raça Poodle, 33 fêmeas, média de idade de 8,71±2,8 anos, com HACAD, e 50 cães Poodles saudáveis, 32 fêmeas, média de idade de 9,4±2,8 anos, foram estudados. Mutações na região codificadora do gene Tpit não foram identificadas. Foi observado um novo polimorfismo em heterozigose, p.S343G, com a mesma frequência no grupo de cães com HACAD e no grupo-controle. Conclui-se que a mutação ativadora no gene Tpit não está envolvida na patogênese do hiperadrenocorticismo ACTH-dependente em cães da raça Poodle

L-levothyroxine therapeutic dosage evaluation in dogs with primary hypothyroidism

O hipotireoidismo primário adquirido é uma endocrinopatia frequentemente diagnosticada na espécie canina. A terapia consiste na suplementação oral com levotiroxina sódica (L-tiroxina), no entanto vários protocolos terapêuticos têm sido propostos pela literatura, com doses variando 11 a 44µg/kg uma a duas vezes ao dia, visto à grande variabilidade de absorção e meia-vida plasmática do fármaco. Foram estudados 30 cães com hipotiroidismo primário adquirido (13 machos e 17 fêmeas, idade média de 7,9±1,9 anos e peso médio de 19,1±12,6 kg) atendidos no Hospital Veterinário da Universidade Guarulhos (UnG) e no Serviço de Endocrinologia de duas clínicas particulares da cidade de São Paulo (2009-2011), com o objetivo de avaliar a posologia e a frequência de administração da L-tiroxina, mais frequentemente utilizada, capaz de garantir um controle terapêutico satisfatório, avaliado através dos sinais clínicos e do teste pós-tiroxina, além de correlacionar a dose de tiroxina empregada com o peso dos animais. A dose média de tiroxina utilizada em nossa casuística foi de 16,9±3,1µg/kg, sendo a frequência de administração a cada 12 horas em 50% dos casos. Para se investigar uma possível correlação entre o peso e a dosagem de tiroxina utilizada, uma vez que cães de pequeno porte apresentam maior taxa metabólica que cães de grande porte, os animais foram agrupados em grupo A, cães com peso <10 Kg (n=12/30; 7,7±2,1 kg) e grupo B, cães com peso >10 kg (n=18/30, 26,8±10,7 kg). A dose média de tiroxina empregada nos grupos A e B não apresentaram diferença estatística e foram, respectivamente, 16±3µg/kg e 17±3µg/kg. A frequência de administração foi 50% a cada 24 horas e 50% a cada 12 horas para ambos os grupos. Dessa forma, a dose de tiroxina não parece se correlacionar com o peso do animal, sendo imprevisível quem deverá receber dose e frequência máxima da medicação. O protocolo deve ser individualizado e o paciente devidamente monitorado.The acquired primary hypothyroidism is a frequently diagnosed endocrinopathy in dogs. The therapy constitutes in oral supplementation with sodium levothyroxine (L-thyroxine), however various therapeutic protocols have been proposed in the literature, with doses ranging from 11 to 44mg/kg once or twice a day, since L-thyroxine has a great variability of absorption and plasma half life. We studied 30 dogs with primary hypothyroidism (13 males and 17 females, mean age 7.9 +/- 1.9 years and mean weight of 19.1 +/- 12.6 kg), in order to evaluate the dose and frequency of administration of L-thyroxine used more often able to secure a satisfactory therapeutic control as measured by clinical signs and test post-pill, and to correlate the amount of thyroxine employed with the animals' weight. The mean dose of thyroxine used in our study was 16.9 +/- 3.1mg/kg, and the frequency of administration every 12 hours in 50% of cases. To investigate a possible correlation between weight and dose of thyroxine used, since small dogs have a higher metabolic rate than large dogs, the animals were grouped in Group A, dogs weighing &lt;= 10 kg (n=12/30, 7.7 +/- 2.1 kg) and group B, dogs weighing&gt; 10 kg (n=18/30, 26.8 +/- 10.7 kg). The mean dose of thyroxine used in groups A and B did not differ significantly and were respectively 16 +/- 3mg/kg and 17 +/- 3mg/kg. The frequency of administration was 50% every 24 hours and 50% every 12 hours for both groups. Thus, the dose of thyroxine does not seem to correlate with the weight of the animal being unpredictable who should receive the highest dose and frequency of the medication. The protocol should be individualized and the patient adequately monitored

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

X-ray emission from the Sombrero galaxy: discrete sources

We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres

Search for New Physics with Jets and Missing Transverse Momentum in pp collisions at sqrt(s) = 7 TeV

A search for new physics is presented based on an event signature of at least three jets accompanied by large missing transverse momentum, using a data sample corresponding to an integrated luminosity of 36 inverse picobarns collected in proton--proton collisions at sqrt(s)=7 TeV with the CMS detector at the LHC. No excess of events is observed above the expected standard model backgrounds, which are all estimated from the data. Exclusion limits are presented for the constrained minimal supersymmetric extension of the standard model. Cross section limits are also presented using simplified models with new particles decaying to an undetected particle and one or two jets

Measurement of the Z/gamma* + b-jet cross section in pp collisions at 7 TeV

The production of b jets in association with a Z/gamma* boson is studied using proton-proton collisions delivered by the LHC at a centre-of-mass energy of 7 TeV and recorded by the CMS detector. The inclusive cross section for Z/gamma* + b-jet production is measured in a sample corresponding to an integrated luminosity of 2.2 inverse femtobarns. The Z/gamma* + b-jet cross section with Z/gamma* to ll (where ll = ee or mu mu) for events with the invariant mass 60 < M(ll) < 120 GeV, at least one b jet at the hadron level with pT > 25 GeV and abs(eta) < 2.1, and a separation between the leptons and the jets of Delta R > 0.5 is found to be 5.84 +/- 0.08 (stat.) +/- 0.72 (syst.) +(0.25)/-(0.55) (theory) pb. The kinematic properties of the events are also studied and found to be in agreement with the predictions made by the MadGraph event generator with the parton shower and the hadronisation performed by PYTHIA.Comment: Submitted to the Journal of High Energy Physic