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3.
Dalton Trans ; 40(36): 9136-44, 2011 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-21818485

RESUMO

The solvothermal reactions (at 180 °C for 48 h) of a mixture of lanthanide chlorides (Nd, Eu) with the tridendate heterocyclic nitrogen ligand, 2,2':6',2''-terpyridine (terpy), in ethanol medium give rise to the formation of crystalline mixed chloro-hydroxo-aquo complex Ln(2)Cl(5)(OH)(H(2)O)(terpy). Its crystal structure consists of the connection of eight- and nine-fold coordinated lanthanide centers linked to each other via µ(2,3)-chloro and µ(3)-hydroxo species to form a tetranuclear unit, which are then further connected through chloro edges to generate infinite ribbons. Only one lanthanide cation in every two is chelated by terpy. Similar molar composition of the starting reactants led to the crystallization at room temperature of a second type of complex LnCl(3)(H(2)O)(terpy) (Ln = Nd, Eu). It is built up from the molecular assembly of dinuclear species containing two eight-fold coordinated lanthanide centers chelated by terpy and linked through a µ(2)-Cl edge. Luminescence spectra have been collected for the europium-based compound and indicates a strong red signal with the expected bands from the F-D transitions. The magnetic properties of the four compounds were investigated. Their behaviors correspond to that of the rare-earth ions present in the structure. The magnetic susceptibility of the neodymium-based compounds agrees with that of the Nd(III) ion with an (4)I(9/2) ground state split by crystal field. Concerning the Eu(III) derivatives, the term (7)F is split by spin-orbit coupling, the first excited states being thermally populated. Accordingly, the thermal dependence of the magnetic susceptibility was nicely reproduced by using appropriate analytical relations. The refined values of the spin-orbit coupling are consistent with the energies of the electronic levels deduced from the photoluminescence spectra. Unexpectedly, the magnetic susceptibility exhibits a hysteretic behavior in the range 45-75 K.


Assuntos
Cloretos/química , Európio/química , Neodímio/química , Compostos Organometálicos/química , Piridinas/química , Cloretos/síntese química , Cristalografia por Raios X , Luminescência , Modelos Moleculares , Compostos Organometálicos/síntese química , Piridinas/síntese química
5.
Acta Cytol ; 50(4): 372-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16900997

RESUMO

OBJECTIVE: To review the cytologic features and potential pitfalls of pheochromocytoma and retroperitoneal paraganglioma and to evaluate complications of the aspiration procedure and the diagnostic utility of immunocytochemistry. STUDY DESIGN: We reviewed 15 cytologic specimens from 12 patients with 13 tumors (1 bilateral case). Ten were adrenal (pheochromocytomas) and 3 extraadrenal paragangliomas. Eleven specimens were from fine needle aspiration (FNA) procedures that were performed in collaboration with radiologists using 23-25-gauge needles. In 3 patients the cytologic material was obtained during intraoperative diagnosis. Immunocytochemistry was performed on alcohol-fixed smears. RESULTS: Two aspirates were hypocellular, while the remainder were cellular. Cells were distributed singly or formed discohesive groups. When present, cytoplasm was abundant and ill defined. Most cells had an eccentric nucleus and plasmacytoid morphology. Nuclear pleomorphism, binucleation and multinucletaion, naked nuclei and intranuclear preudoinclusions were common findings. In 2 cases a lipid background was seen focally. Evident cytoplasmic immunoexpression of synaptophysin or chromogranin was detected in the 10 cases analyzed. One patient developed a hypertensive episode during the FNA procedure. It was controlled medically without complications. CONCLUSION: When adequate cytologic material is present, the recognition of pheochromocytoma and extraadrenal paraganglioma is possible. Together with morphology, immunocytochemical studies allow a specific preoperative diagnosis. Scarce material can be a source of diagnostic errors. FNA of pheochromocytomas is not necessarily contraindicated. When analytic data are not diagnostic, FNA may follow. Aspiration must be performed in an area equipped with the therapeutic tools necessary to control a pheochromocytoma crisis.


Assuntos
Feocromocitoma/patologia , Neoplasias Retroperitoneais/patologia , Adolescente , Adulto , Idoso , Biópsia por Agulha Fina , Citoplasma/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Sinaptofisina/metabolismo
7.
Acta Cytol ; 48(3): 295-301, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15192942

RESUMO

OBJECTIVE: To analyze the role of fine needle aspiration (FNA) cytology in the preoperative diagnosis of pancreatic endocrine neoplasms. METHODS: Cytologic and histologic diagnoses of pancreatic endocrine tumors were reviewed. A total of 20 FNA cytologic procedures from 20 patients were selected. A false positive case, a retroperitoneal paraganglioma, was also reviewed. Two groups of patients were established: (1) those in whom a surgical biopsy with an immunohistochemical study was available (n = 13), and (2) those with a pancreatic tumor in which the diagnosis was confirmed by immunocytochemical studies (n = 7). In 13 cases the pancreatic tumor was aspirated, while in 7, liver metastases were studied. The immunoexpression of chromogranin and synaptophysin was evaluated in alcohol-fixed smears from 12 and 11 cases, respectively. RESULTS: One false negative and 1 false positive diagnosis were present. In the remaining 19 cases a cytologic diagnosis of pancreatic endocrine tumor was given. Main cytologic features were: (1) a prominent cellular dissociation with many single cells and small, poorly cohesive groups; (2) intermediate to large size cells with ill-defined cytoplasm, naked or eccentric nuclei, and frequent binucleation; and (3) variable nuclear pleomorphism with the characteristic finely granular distribution of the chromatin. Immunocytochemical evidence of endocrine differentiation (chromogranin or synaptophysin) was present in the 12 cases analyzed. CONCLUSION: FNA cytology offers the possibility of a precise preoperative, noninvasive diagnosis of pancreatic endocrine tumors. Cytologic features differ considerably from those of pancreatic adenocarcinoma, allowing differentiation from nonfunctioning endocrine neoplasms. In difficult cases immunocytologic studies are very helpful.


Assuntos
Neoplasias das Glândulas Endócrinas/diagnóstico , Neoplasias das Glândulas Endócrinas/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Adulto , Idoso , Biópsia por Agulha Fina , Cromograninas/análise , Citodiagnóstico , Diagnóstico Diferencial , Neoplasias das Glândulas Endócrinas/imunologia , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Imuno-Histoquímica , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/imunologia , Sinaptofisina/análise
9.
Acta Cytol ; 48(1): 47-51, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14969180

RESUMO

OBJECTIVE: To evaluate the presence of basement membrane stromal material in fine needle aspiration (FNA) and scrape cytologic specimens from patients with clear cell carcinoma (CCC) of the female genital tract. STUDY DESIGN: The study group consisted of 6 patients with CCC (5 ovarian and 1 cervical). Four samples corresponded to FNA specimens and 3 to scrape material obtained during intraoperative consultation for ovarian tumors. FNA was performed on a pelvic recurrence and on liver, pulmonary and lymph node metastases. The 6 cases had a complete histopathologic study. RESULTS: In addition to large, clear cells, all cases showed basement membrane stromal material that assumed several forms. The most common was globular, hyaline structures, either naked or surrounded by neoplastic epithelial cells ("raspberry bodies"). Other fragments were larger, with several spherules and elongated prolongations. Scrape material showed stromal material resembling reduplicated basement membrane material. In Diff-Quik-stained smears (QCA, Tarragana, Spain) it showed metachromatic staining with a pink to purple color. Its recognition on Papanicolaou-stained smears was more difficult since it did not stain or was gray. CONCLUSION: Basement membrane stromal material and, more precisely, "raspberry bodies," are a characteristic cytologic feature of CCC of the female genital tract. The combination of clear, atypical cells and basement membrane stroma is highly specific to this neoplasm and can be observed not only in exfoliative specimens but also in FNA and scrape samples.


Assuntos
Adenocarcinoma de Células Claras/patologia , Neoplasias dos Genitais Femininos/patologia , Células Estromais/patologia , Membrana Basal/patologia , Biópsia por Agulha Fina , Feminino , Humanos , Hialina/metabolismo , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
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