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1.
Phys Rev Lett ; 131(20): 202301, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38039468

RESUMO

The polarization of Λ and Λ[over ¯] hyperons along the beam direction has been measured relative to the second and third harmonic event planes in isobar Ru+Ru and Zr+Zr collisions at sqrt[s_{NN}]=200 GeV. This is the first experimental evidence of the hyperon polarization by the triangular flow originating from the initial density fluctuations. The amplitudes of the sine modulation for the second and third harmonic results are comparable in magnitude, increase from central to peripheral collisions, and show a mild p_{T} dependence. The azimuthal angle dependence of the polarization follows the vorticity pattern expected due to elliptic and triangular anisotropic flow, and qualitatively disagrees with most hydrodynamic model calculations based on thermal vorticity and shear induced contributions. The model results based on one of existing implementations of the shear contribution lead to a correct azimuthal angle dependence, but predict centrality and p_{T} dependence that still disagree with experimental measurements. Thus, our results provide stringent constraints on the thermal vorticity and shear-induced contributions to hyperon polarization. Comparison to previous measurements at RHIC and the LHC for the second-order harmonic results shows little dependence on the collision system size and collision energy.

2.
Phys Rev Lett ; 130(24): 242301, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37390421

RESUMO

The elliptic (v_{2}) and triangular (v_{3}) azimuthal anisotropy coefficients in central ^{3}He+Au, d+Au, and p+Au collisions at sqrt[s_{NN}]=200 GeV are measured as a function of transverse momentum (p_{T}) at midrapidity (|η|<0.9), via the azimuthal angular correlation between two particles both at |η|<0.9. While the v_{2}(p_{T}) values depend on the colliding systems, the v_{3}(p_{T}) values are system independent within the uncertainties, suggesting an influence on eccentricity from subnucleonic fluctuations in these small-sized systems. These results also provide stringent constraints for the hydrodynamic modeling of these systems.


Assuntos
Hidrodinâmica , Masculino , Humanos , Anisotropia , Movimento (Física)
3.
Phys Rev Lett ; 130(21): 212301, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37295104

RESUMO

We report here the first observation of directed flow (v_{1}) of the hypernuclei _{Λ}^{3}H and _{Λ}^{4}H in mid-central Au+Au collisions at sqrt[s_{NN}]=3 GeV at RHIC. These data are taken as part of the beam energy scan program carried out by the STAR experiment. From 165×10^{6} events in 5%-40% centrality, about 8400 _{Λ}^{3}H and 5200 _{Λ}^{4}H candidates are reconstructed through two- and three-body decay channels. We observe that these hypernuclei exhibit significant directed flow. Comparing to that of light nuclei, it is found that the midrapidity v_{1} slopes of _{Λ}^{3}H and _{Λ}^{4}H follow baryon number scaling, implying that the coalescence is the dominant mechanism for these hypernuclei production in the 3 GeV Au+Au collisions.

4.
Phys Rev Lett ; 130(20): 202301, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37267557

RESUMO

We report the triton (t) production in midrapidity (|y|<0.5) Au+Au collisions at sqrt[s_{NN}]=7.7-200 GeV measured by the STAR experiment from the first phase of the beam energy scan at the Relativistic Heavy Ion Collider. The nuclear compound yield ratio (N_{t}×N_{p}/N_{d}^{2}), which is predicted to be sensitive to the fluctuation of local neutron density, is observed to decrease monotonically with increasing charged-particle multiplicity (dN_{ch}/dη) and follows a scaling behavior. The dN_{ch}/dη dependence of the yield ratio is compared to calculations from coalescence and thermal models. Enhancements in the yield ratios relative to the coalescence baseline are observed in the 0%-10% most central collisions at 19.6 and 27 GeV, with a significance of 2.3σ and 3.4σ, respectively, giving a combined significance of 4.1σ. The enhancements are not observed in peripheral collisions or model calculations without critical fluctuation, and decreases with a smaller p_{T} acceptance. The physics implications of these results on the QCD phase structure and the production mechanism of light nuclei in heavy-ion collisions are discussed.

5.
Phys Rev Lett ; 130(11): 112301, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-37001106

RESUMO

We report on measurements of sequential ϒ suppression in Au+Au collisions at sqrt[s_{NN}]=200 GeV with the STAR detector at the Relativistic Heavy Ion Collider (RHIC) through both the dielectron and dimuon decay channels. In the 0%-60% centrality class, the nuclear modification factors (R_{AA}), which quantify the level of yield suppression in heavy-ion collisions compared to p+p collisions, for ϒ(1S) and ϒ(2S) are 0.40±0.03(stat)±0.03(sys)±0.09(norm) and 0.26±0.08(stat)±0.02(sys)±0.06(norm), respectively, while the upper limit of the ϒ(3S) R_{AA} is 0.17 at a 95% confidence level. This provides experimental evidence that the ϒ(3S) is significantly more suppressed than the ϒ(1S) at RHIC. The level of suppression for ϒ(1S) is comparable to that observed at the much higher collision energy at the Large Hadron Collider. These results point to the creation of a medium at RHIC whose temperature is sufficiently high to strongly suppress excited ϒ states.

6.
Phys Rev Lett ; 130(8): 082301, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36898098

RESUMO

We report the beam energy and collision centrality dependence of fifth and sixth order cumulants (C_{5}, C_{6}) and factorial cumulants (κ_{5}, κ_{6}) of net-proton and proton number distributions, from center-of-mass energy (sqrt[s_{NN}]) 3 GeV to 200 GeV Au+Au collisions at RHIC. Cumulant ratios of net-proton (taken as proxy for net-baryon) distributions generally follow the hierarchy expected from QCD thermodynamics, except for the case of collisions at 3 GeV. The measured values of C_{6}/C_{2} for 0%-40% centrality collisions show progressively negative trend with decreasing energy, while it is positive for the lowest energy studied. These observed negative signs are consistent with QCD calculations (for baryon chemical potential, µ_{B}≤110 MeV) which contains the crossover transition range. In addition, for energies above 7.7 GeV, the measured proton κ_{n}, within uncertainties, does not support the two-component (Poisson+binomial) shape of proton number distributions that would be expected from a first-order phase transition. Taken in combination, the hyperorder proton number fluctuations suggest that the structure of QCD matter at high baryon density, µ_{B}∼750 MeV at sqrt[s_{NN}]=3 GeV is starkly different from those at vanishing µ_{B}∼24 MeV at sqrt[s_{NN}]=200 GeV and higher collision energies.

7.
Phys Rev Lett ; 129(9): 092501, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36083674

RESUMO

The STAR Collaboration reports measurements of back-to-back azimuthal correlations of di-π^{0}s produced at forward pseudorapidities (2.6<η<4.0) in p+p, p+Al, and p+Au collisions at a center-of-mass energy of 200 GeV. We observe a clear suppression of the correlated yields of back-to-back π^{0} pairs in p+Al and p+Au collisions compared to the p+p data. The observed suppression of back-to-back pairs as a function of transverse momentum suggests nonlinear gluon dynamics arising at high parton densities. The larger suppression found in p+Au relative to p+Al collisions exhibits a dependence of the saturation scale Q_{s}^{2} on the mass number A. A linear scaling of the suppression with A^{1/3} is observed with a slope of -0.09±0.01.

9.
Phys Rev Lett ; 128(20): 202301, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35657899

RESUMO

We report precision measurements of hypernuclei _{Λ}^{3}H and _{Λ}^{4}H lifetimes obtained from Au+Au collisions at sqrt[s_{NN}]=3.0 GeV and 7.2 GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider, and the first measurement of _{Λ}^{3}H and _{Λ}^{4}H midrapidity yields in Au+Au collisions at sqrt[s_{NN}]=3.0 GeV. _{Λ}^{3}H and _{Λ}^{4}H, being the two simplest bound states composed of hyperons and nucleons, are cornerstones in the field of hypernuclear physics. Their lifetimes are measured to be 221±15(stat)±19(syst) ps for _{Λ}^{3}H and 218±6(stat)±13(syst) ps for _{Λ}^{4}H. The p_{T}-integrated yields of _{Λ}^{3}H and _{Λ}^{4}H are presented in different centrality and rapidity intervals. It is observed that the shape of the rapidity distribution of _{Λ}^{4}H is different for 0%-10% and 10%-50% centrality collisions. Thermal model calculations, using the canonical ensemble for strangeness, describes the _{Λ}^{3}H yield well, while underestimating the _{Λ}^{4}H yield. Transport models, combining baryonic mean-field and coalescence (jam) or utilizing dynamical cluster formation via baryonic interactions (phqmd) for light nuclei and hypernuclei production, approximately describe the measured _{Λ}^{3}H and _{Λ}^{4}H yields. Our measurements provide means to precisely assess our understanding of the fundamental baryonic interactions with strange quarks, which can impact our understanding of more complicated systems involving hyperons, such as the interior of neutron stars or exotic hypernuclei.

10.
Phys Rev Lett ; 128(12): 122303, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35394314

RESUMO

Understanding gluon density distributions and how they are modified in nuclei are among the most important goals in nuclear physics. In recent years, diffractive vector meson production measured in ultraperipheral collisions (UPCs) at heavy-ion colliders has provided a new tool for probing the gluon density. In this Letter, we report the first measurement of J/ψ photoproduction off the deuteron in UPCs at the center-of-mass energy sqrt[s_{NN}]=200 GeV in d+Au collisions. The differential cross section as a function of momentum transfer -t is measured. In addition, data with a neutron tagged in the deuteron-going zero-degree calorimeter is investigated for the first time, which is found to be consistent with the expectation of incoherent diffractive scattering at low momentum transfer. Theoretical predictions based on the color glass condensate saturation model and the leading twist approximation nuclear shadowing model are compared with the data quantitatively. A better agreement with the saturation model has been observed. With the current measurement, the results are found to be directly sensitive to the gluon density distribution of the deuteron and the deuteron breakup process, which provides insights into the nuclear gluonic structure.

11.
Phys Rev Lett ; 128(9): 092301, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35302834

RESUMO

The chiral magnetic effect (CME) refers to charge separation along a strong magnetic field due to imbalanced chirality of quarks in local parity and charge-parity violating domains in quantum chromodynamics. The experimental measurement of the charge separation is made difficult by the presence of a major background from elliptic azimuthal anisotropy. This background and the CME signal have different sensitivities to the spectator and participant planes, and could thus be determined by measurements with respect to these planes. We report such measurements in Au+Au collisions at a nucleon-nucleon center-of-mass energy of 200 GeV at the Relativistic Heavy-Ion Collider. It is found that the charge separation, with the flow background removed, is consistent with zero in peripheral (large impact parameter) collisions. Some indication of finite CME signals is seen in midcentral (intermediate impact parameter) collisions. Significant residual background effects may, however, still be present.

12.
Phys Rev Lett ; 129(25): 252301, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36608250

RESUMO

Elliptic flow measurements from two-, four-, and six-particle correlations are used to investigate flow fluctuations in collisions of U+U at sqrt[s_{NN}]=193 GeV, Cu+Au at sqrt[s_{NN}]=200 GeV and Au+Au spanning the range sqrt[s_{NN}]=11.5-200 GeV. The measurements show a strong dependence of the flow fluctuations on collision centrality, a modest dependence on system size, and very little if any, dependence on particle species and beam energy. The results, when compared to similar LHC measurements, viscous hydrodynamic calculations, and trento model eccentricities, indicate that initial-state-driven fluctuations predominate the flow fluctuations generated in the collisions studied.

13.
Phys Rev Lett ; 127(26): 262301, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35029466

RESUMO

According to first-principle lattice QCD calculations, the transition from quark-gluon plasma to hadronic matter is a smooth crossover in the region µ_{B}≤T_{c}. In this range the ratio, C_{6}/C_{2}, of net-baryon distributions are predicted to be negative. In this Letter, we report the first measurement of the midrapidity net-proton C_{6}/C_{2} from 27, 54.4, and 200 GeV Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). The dependence on collision centrality and kinematic acceptance in (p_{T}, y) are analyzed. While for 27 and 54.4 GeV collisions the C_{6}/C_{2} values are close to zero within uncertainties, it is observed that for 200 GeV collisions, the C_{6}/C_{2} ratio becomes progressively negative from peripheral to central collisions. Transport model calculations without critical dynamics predict mostly positive values except for the most central collisions within uncertainties. These observations seem to favor a smooth crossover in the high-energy nuclear collisions at top RHIC energy.

14.
Physiol Res ; 64(3): 369-77, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25536318

RESUMO

This study investigated quantitated expression of dopamine 2 receptor (D2R) and somatostatin receptors of the five types (SSTR1-SSTR5) in a large series of clinically non-functioning pituitary adenomas (CNFAs). Co-expression of these receptors in individual adenomas was studied as well as correlation between receptor types. Adenoma tissue from 198 patients who underwent surgery for CNFAs was analyzed by immunohistochemistry and quantitative real-time PCR. D2R and SSTR1-3 mRNA was expressed in all 198 adenomas. SSTR4 and SSTR5 were detectable in 85 % and 61 % of adenomas, respectively. Expression of D2R was significantly higher than that of the somatostatin receptors. The median relative expressions were as follows from highest D2R >> SSTR3 > SSTR2 > SSTR1 > SSTR5 > SSTR4. High relative expression (ratio to beta-glucuronidase mRNA > 1) of D2R was found in 60 % of tumors, high expression of SSTR1 in 7.5 %, SSTR2 in 7 %, SSTR3 in 4 % and SSTR5 in 0.5 %. The quantity of D2R correlated positively with expression of SSTR2 and SSTR3, and negatively with SSTR1 and SSTR5. Among histological adenoma types, SSTR1 was significantly higher in null-cell adenomas and SSTR3 was lower in silent corticotroph adenomas. In conclusions, in CNFAs, high expression of somatostatin receptors is much less common than that of D2R, and co-expression of both these receptors is exceptional. D2R and SSTR3 seem to be the most promising targets for pharmacological treatment.


Assuntos
Adenoma/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Hipofisárias/metabolismo , Receptores de Dopamina D2/metabolismo , Receptores de Somatostatina/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade
15.
Cytopathology ; 26(4): 231-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25077794

RESUMO

OBJECTIVES: To retrospectively reclassify the results of fine needle aspiration (FNA) cytology at our institution according to the Bethesda system for reporting thyroid cytopathology (TBSRTC), and to determine whether the introduction of the new classification system would have influenced the diagnostic accuracy compared with our existing system in which suspicious/indeterminate categories (categories III-IV) are managed according to clinical findings and cytopathologists' recommendations. METHODS: FNAs performed under ultrasound guidance between 2001 and 2012, and subsequently verified by histology or repeat FNA and follow-up, were reviewed and retrospectively reclassified according to TBSRTC. RESULTS: Among a total of 1310 histologically verified FNAs, the positive predictive values (%) for malignancy and neoplasia (carcinoma + follicular adenomas) for category I-VI according to the TBSRTC were 5.7/11.3, 2.6/5.5, 14.4/34.2, 23.6/55.0, 57.0/64.5 and 92.2/94.2, respectively. Although all the categories predict malignancy closely, the difference in malignancy rate between categories III and IV was not statistically significant; however, the difference in total neoplasia rate reached statistical significance. When patients with cytological and clinical follow-up were included, the malignancy rated dropped in category I to 2.4%, whereas, in category III, it remained at 13%. Repeat FNA instead of direct surgery spared half of the patients from surgery. The cytopathologists' recommendations for histological verification in category III were associated with an insignificant increase in malignancy rate, but the total neoplasia rate reached 57.5%. CONCLUSIONS: At our institution, the application of the TBSRTC did not improve the diagnostic accuracy for the detection of malignancy compared with current practice. In selected cases with cytological results falling into category III (according to clinical data and cytopathologists' opinions), direct lobectomy seems to be justified.


Assuntos
Glândula Tireoide/patologia , Biópsia por Agulha Fina/métodos , Citodiagnóstico/métodos , Humanos , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/patologia
16.
Eur J Endocrinol ; 171(6): 727-35, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25240499

RESUMO

OBJECTIVE: Medical management of primary hyperparathyroidism (PHPT) is important in patients for whom surgery is inappropriate. We aimed to describe clinical profiles of adults with PHPT receiving cinacalcet. DESIGN: A descriptive, prospective, observational study in hospital and specialist care centres. METHODS: For patients with PHPT, aged 23-92 years, starting cinacalcet treatment for the first time, information was collected on dosing pattern, biochemistry and adverse drug reactions (ADRs). Initial cinacalcet dosage and subsequent dose changes were at the investigator's discretion. RESULTS: Of 303 evaluable patients with PHPT, 134 (44%) had symptoms at diagnosis (mostly bone pain (58) or renal stones (50)). Mean albumin-corrected serum calcium (ACSC) at baseline was 11.4 mg/dl (2.9 mmol/l). The reasons for prescribing cinacalcet included: surgery deemed inappropriate (35%), patient declined surgery (28%) and surgery failed or contraindicated (22%). Mean cinacalcet dose was 43.9 mg/day (s.d., 15.8) at treatment start and 51.3 mg/day (31.8) at month 12; 219 (72%) patients completed 12 months treatment. The main reason for cinacalcet discontinuation was parathyroidectomy (40; 13%). At 3, 6 and 12 months from the start of treatment, 63, 69 and 71% of patients, respectively, had an ACSC of ≤10.3 mg/dl vs 9.9% at baseline. Reductions from baseline in ACSC of ≥1 mg/dl were seen in 56, 63 and 60% of patients respectively. ADRs were reported in 81 patients (27%), most commonly nausea. A total of 7.6% of patients discontinued cinacalcet due to ADRs. CONCLUSIONS: Reductions in calcium levels of ≥1 mg/dl was observed in 60% of patients 12 months after initiation of cinacalcet, without notable safety concerns.


Assuntos
Hiperparatireoidismo Primário/tratamento farmacológico , Hiperparatireoidismo Primário/epidemiologia , Naftalenos/uso terapêutico , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Cinacalcete , Relação Dose-Resposta a Droga , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
17.
Vnitr Lek ; 59(9): 819-27, 2013 Sep.
Artigo em Tcheco | MEDLINE | ID: mdl-24073954

RESUMO

Cushing's syndrome is a rare disorder with variable aetiology which is connected with significantly increased morbidity and mortality. Therefore, early determination of correct aetiology and early treatment are essential for a decrease of morbidity and mortality of patients. Present article introduces review and current recommendation of Czech Society of Endocrinology for the treatment of Cushings syndrome.


Assuntos
Síndrome de Cushing/tratamento farmacológico , Endocrinologia , Sociedades Médicas , Adulto , Síndrome de Cushing/etiologia , República Tcheca , Humanos
18.
Transplant Proc ; 45(2): 770-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23498819

RESUMO

OBJECTIVE: The diagnosis of sepsis is difficult in immunocompromised patients owing to their modified response to infection. Our experiment in minipigs was designed to compare responses to sepsis between experimental groups of septic minipigs with and without immunosuppression. METHODS: Minipigs with identical baseline parameters were randomized into 3 groups: Sepsis (n = 10); immunosuppression (n = 11), including cyclosporine, methylprednisolone, and mycophenolate mofetil treatment before surgery, and a sham group (n = 6). Sepsis was induced by cecal ligation and puncture (CLP). We recorded selected clinical and laboratory parameters up to 24 hours postoperatively. RESULTS: All CLP animals developed septic shock with a febrile response, tachycardia, and hypotension requiring noradrenaline administration. The hemodynamic responses to sepsis in septic groups with and without immunosuppression were similar. Noradrenaline infusion was started on average later in the immunosuppression than in the group without immunosuppression; however, the difference was not significant. The kinetics of the plasma levels of most selected cytokines and C-reactive protein were similar in both septic groups. At 10 hours after surgery, the immunosuppression group showed significantly lower interleukin (IL)-6 levels compared with the sepsis group. At 19, 22, and 25 hours after surgery immunosuppressed animals displayed significantly greater increases in IL-10 levels compared with the cohort without immunosuppression. CONCLUSIONS: CLP is a simple, reproducible model of sepsis in minipigs. All CLP animals developed sepsis within 24 hours on average. Significant differences in IL-6 and IL-10 plasma levels were recorded between septic animals with versus without immunosuppression.


Assuntos
Ceco/cirurgia , Hospedeiro Imunocomprometido , Imunossupressores/farmacologia , Sepse/imunologia , Animais , Biomarcadores/sangue , Cardiotônicos/farmacologia , Ceco/microbiologia , Ciclosporina/farmacologia , Modelos Animais de Doenças , Hemodinâmica , Mediadores da Inflamação/sangue , Ligadura , Metilprednisolona/farmacologia , Ácido Micofenólico/análogos & derivados , Norepinefrina/farmacologia , Punções , Sepse/sangue , Sepse/tratamento farmacológico , Sepse/microbiologia , Sepse/fisiopatologia , Suínos , Porco Miniatura , Fatores de Tempo
19.
Vnitr Lek ; 58(3): 228-31, 2012 Mar.
Artigo em Tcheco | MEDLINE | ID: mdl-22486290

RESUMO

Low testosterone level is common in obese men and even more frequent in the presence of type 2 diabetes mellitus. Low testosterone level is probably not caused by increased aromatization of testosterone to estradiol in fat tissue. Increase of inflammation mediators, insulin and leptin resistance and low SHBG level may play more important role. Low testosterone level may manifest with low libido, erectile dysfunction, fatigue and depressive mood; it has a role in development of anaemia, osteoporosis, worsening of insulin resistance and it is probably marker of increased all-case and cardiovascular mortality. Routine investigation of testosterone level is indicated in every man with type 2 diabetes mellitus. As in non-diabetic men of middle and higher age substitution is indicated only in presence of clinical symptoms of hypogonadism. The substitution improves mainly libido, erectile dysfunction is influenced less. However, the phosphodiasterase-5 inhibitors efficiency is markedly improved. Metabolic changes during testosterone substitution are small.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Testosterona/deficiência , Diabetes Mellitus Tipo 2/complicações , Terapia de Reposição Hormonal , Humanos , Hipogonadismo/complicações , Hipogonadismo/terapia , Resistência à Insulina , Masculino , Obesidade/metabolismo
20.
Cytopathology ; 23(1): 39-44, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21198996

RESUMO

INTRODUCTION: The aim of our study was to search for new, readily available and statistically reliable cytological markers for differentiating benign and malignant follicular thyroid neoplasms pre-operatively. METHODS: Cohesiveness of tumour cells in cytology slides from a series of 58 follicular tumours diagnosed between 1998 and 2004 inclusive was studied, including 48 follicular adenomas, and eight minimally invasive and two widely invasive follicular carcinomas. Photomicrographs of the cytology slides were taken and the digital images were analysed using computer image analysis software. We evaluated the relative proportions of cells arranged in groups of various sizes. The cohesiveness of the cells in cytological smears was then correlated with the immunohistochemical expression of E-cadherin in corresponding histological slides. RESULTS: Cases from 15 men (26%) and 43 women (74%) with a mean age of 50 years (range, 19-79) were analysed. In follicular adenomas and carcinomas, respectively, isolated cells were seen in 16.8% and 24.7% (P = 0.028), groups of two to five cells in 9.7% and 11.5% (P = 0.145) and groups of more than five cells in 73.5% and 63.8% (P = 0.041). The mean cell count in groups with more than five cells was 46.5 and 27.0 in adenomas and carcinomas, respectively (P < 0.001). Cell cohesiveness, either as percentage of cells in groups of more than five (R(2) = 0.026) or as mean cell count per group of more than five (R(2) = 0.005), was not found to be dependent on the expression of E-cadherin. Using a threshold of 13% isolated tumour cells in cytological smears, follicular adenomas and carcinomas could be distinguished with 90% sensitivity and 41% specificity. CONCLUSIONS: Although we demonstrated a statistically significant difference in cell cohesion between follicular adenomas and carcinomas, these could not be distinguished in the clinical setting by evaluation of the percentage of isolated cells in cytological smears because the specificity was too low. The absence of correlation of cellular cohesiveness with E-cadherin expression indicates that other factors are probably responsible for the loss of cohesiveness observed in follicular thyroid malignancy.


Assuntos
Adenocarcinoma Folicular/patologia , Adenoma/patologia , Biomarcadores Tumorais/análise , Nódulo da Glândula Tireoide/patologia , Adenocarcinoma Folicular/química , Adenoma/química , Adulto , Idoso , Biópsia por Agulha Fina , Caderinas/análise , Adesão Celular , Diagnóstico Diferencial , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Nódulo da Glândula Tireoide/química
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