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1.
Ann Clin Biochem ; 55(1): 172-177, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28388869

RESUMO

Background Thyroid-stimulating hormone (TSH) receptor (TSHR) autoantibodies (TRAbs) are a heterogeneous group of antibodies (Abs) with different functionalities. Among all TRAbs, only the stimulating ones (S-TRAbs) are considered as the pathogenetic marker of Graves' disease (GD). To date, the methods available for TRAbs testing are based on immunoassays (IMAs) which detect total serum TRAbs or bioassays which are not suitable in clinical practice, even though they discern Abs functionality. The aim of our work was to evaluate the analytical and clinical performance of a very recent IMA (Immulite TSI method), supposed to test only the serum concentration of S-TRAbs, in comparison with a current method for total TRAbs (Roche/Elecsys IMA). Methods We evaluated serum samples of 145 subjects: 46 with untreated (GD), 36 with chronic autoimmune thyroiditis, 3 with atrophic thyroiditis, 10 with multinodular non-toxic goiter and 50 healthy subjects. Results The method showed an optimal analytical sensitivity and high precision levels (LoB: 0.04 UI/L, LoD:0.07 UI/L, LoQ:0.14 UI/L, intra-assay CV: 4.2-5.9%, inter-assay: 4.5-7.2%). By receiver operating characteristics curve analysis, we obtained a value of 0.57 (sensitivity: 98.0%, specificity: 99.9%) as the best cut-off to distinguish GD, apart from four cases. Passing Bablok regression and Bland Altman analysis pointed out a good correlation and agreement with Roche method (R2 = 0.98, slope = 1.03, bias = -2.70). Conclusions The new method presents very promising analytical characteristics and could be adopted in clinical practice for GD diagnosis. Moreover, the test allows to accurately detect very low values of analyte with a further clinical utility in detecting earlier possible relapses.


Assuntos
Autoanticorpos/imunologia , Doença de Graves/imunologia , Imunoensaio/métodos , Receptores da Tireotropina/imunologia , Humanos , Sensibilidade e Especificidade
2.
Andrology ; 3(6): 1054-61, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26384478

RESUMO

UNLABELLED: The association between male accessory gland infection/inflammation (MAGI) and infertility is well-known in clinical practice. Standard semen analysis, leukocytospermia, and microbiological tests are often not enough accurate for a diagnosis. A large amount of biochemical parameters in seminal plasma have been suggested as inflammation markers, however, there is not yet a sensitive and specific biomarker that accurately identifies MAGI. We investigated the presence of soluble urokinase-type plasminogen activator receptor (suPAR), known marker of systemic inflammation, in the seminal plasma to evaluate its possible involvement in urogenital tract inflammation. On the basis of andrological evaluation, including spermiogram and ultrasound findings, we selected 76 patients with MAGI and 30 healthy men as control group. Patients were classified according to the results of the semen culture in group A (n = 28) presenting a bacterial MAGI and group B (n = 48) with abacterial MAGI. C-reactive protein (CRP), total protein (TP), procalcitonin (PCT), leukocytes peroxidase (LP), and suPAR concentrations were assayed on seminal plasma. Spermiogram parameters were significantly lower in the patients with MAGI than in controls. CRP, TP, PCT, and LP did not differ in MAGI vs. CONTROLS: suPAR was detectable in all semen samples; it was significantly increased in A and B groups (86.6 ± 30.7 ng/mL vs. 39.7 ± 17.2 ng/mL) with an inverse correlation with sperm parameters. We selected by receiver operating characteristic curve a suPAR cut-off value of 55.3 ng/mL as a diagnostic threshold for the diagnosis of MAGI. We report in this study the first evidence of suPAR presence in seminal plasma, focusing on its interesting role as reliable and sensitive marker of inflammation for the differential diagnosis of MAGI.


Assuntos
Doenças dos Genitais Masculinos/metabolismo , Inflamação/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/análise , Sêmen/química , Adulto , Área Sob a Curva , Biomarcadores/análise , Estudos de Casos e Controles , Diagnóstico Diferencial , Doenças dos Genitais Masculinos/diagnóstico , Doenças dos Genitais Masculinos/microbiologia , Humanos , Inflamação/diagnóstico , Inflamação/microbiologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Sêmen/microbiologia , Análise do Sêmen/métodos
3.
Transpl Infect Dis ; 12(5): 428-31, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20534035

RESUMO

Leishmaniasis is a zoonosis caused by a protozoan of the Leishmania genus. First-line treatment for all forms is currently represented by the use of antimony derivatives, although toxic effects and the number of resistant strains in both immunocompromised and immunocompetent patients is increasing. Liposomal amphotericin B (L-AMB) is less toxic, more effective, and better tolerated, especially in human immunodeficiency virus-negative immunocompromised patients. We present 2 cases of transplanted patients affected by visceral leishmaniasis treated successfully with L-AMB.


Assuntos
Anfotericina B/uso terapêutico , Antiprotozoários/uso terapêutico , Leishmaniose Visceral/tratamento farmacológico , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade
4.
J Phys Chem B ; 112(36): 11264-9, 2008 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-18707084

RESUMO

In this work, polyvinilydene fluoride (PVDF) microcapsules were prepared by using combined emulsion and phase inversion techniques. With this method, microcapsules with different diameters and porosities have been obtained by just controlling the diameter of the membrane used during the preparation. Using a PVDF solution containing the oxidation catalyst ammonium molybdate (20 wt %), catalytic polymeric microcapsules with diameters ranging from 600 to 1,200 microm have been obtained. Characterization of catalytic microcapsules by means of SEM, BSE, and EDX analyses showed a uniform ammonium molybdate dispersion in the polymeric matrix. Catalytic microcapsules have been tested in the oxidation of aromatic primary alcohols to corresponding aldehydes. In the range 600-1,200 microm, the microcapsule diameter influences the formation of oxidation products: in particular, microcapsule diameters >900 microm slightly diminish the formation of aldehyde due to a beginning diffusion limitation. An interesting structure-reactivity behavior, induced by the interaction between the polymeric membrane and the substituted aromatic alcohol, has been observed.

5.
J Agric Food Chem ; 54(18): 6613-22, 2006 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-16939317

RESUMO

Recent studies have documented that grapes and grape juices are equally cardioprotective as red wine. The existing reports implicate that the skin and seeds of the grapes containing polyphenolic antioxidants are instrumental for the cardioprotective properties of grapes. The present study examines if the flesh of grapes also possesses any cardioprotective abilities. Three groups of randomly selected rats were fed, water only (control), flesh of the grapes (2.5 mg/kg b. wt.) or the skins (2.5 mg/kg b. wt.) for 30 days. At the end of the 30 days, isolated perfused hearts were made ischemic for 30 min followed by 2 h of reperfusion in the working mode. The results demonstrated that both flesh and skin of the grapes could protect the hearts from ischemic reperfusion injury as evidenced by improved postischemic ventricular recovery and reduced myocardial infarct size. High performance liquid chromatography (HPLC) revealed that skin and flesh contained comparative amounts of glucose, fructose, tartaric acid, malic acid, shikimic acid, and trans-caftaric acid. In addition, the flesh contained reduced amounts (compared to skin) of cis-coutaric, trans-coutaric, caffeic, p-coumaric, cinnamics, and catechin/epicatechin. Total polyphenolic index was also lower in flesh compared to skin. The anthocyanins were present exclusively in the skin. Electron paramagnetic resonance (EPR) spectrometry of hydroxy radicals indicated that both flesh and skins possessed equal amount of ROS scavenging activities. Total malonaldehyde content in the heart was reduced comparatively with either flesh or skin. The results indicate for the first time that the flesh of grapes are equally cardioprotective as skin, and antioxidant potential of skin and flesh of grapes are comparable with each other despite of the fact that flesh does not possess any anthocyanin activities.


Assuntos
Cardiotônicos/administração & dosagem , Cardiotônicos/análise , Frutas/anatomia & histologia , Frutas/química , Vitis/química , Animais , Antioxidantes/análise , Antioxidantes/farmacologia , Carboidratos/análise , Espectroscopia de Ressonância de Spin Eletrônica , Flavonoides/análise , Masculino , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Fenóis/análise , Polifenóis , Ratos , Ratos Sprague-Dawley
6.
Mol Cell Biochem ; 282(1-2): 65-73, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16317513

RESUMO

Tomato (Lycopersicon esculentum) is a vegetable rich in antioxidants, such as lycopene, lutein, and zeaxanthin. Their presence is responsible for the characteristic ability of this product to inhibit the formation of reactive oxygen species, including singlet oxygen. The grapes and wines derived from grapes also contain powerful antioxidants. The antioxidant effect is derived from the polyphenols such as resveratrol and proanthocyanidin. Resveratrol is phytoalexin that is synthesized via the activation of the gene, stilbene synthase (STS). We decided to determine if the introduction of this gene into Lycopersicon esculentum Mill could modify its antioxidant activity. Using Electronic Paramagnetic Resonance (EPR) spectroscopy, which permits the detection of antiradical activity, especially *OH (hydroxyl radical), we showed that the antioxidant activity of the products, into which the gene STS had been introduced, was almost double than that of natural products and that their activity was especially pronounced due to ripening. Moreover, resveratrol concentrations in modified tomatoes were much higher than that found in the individual fruit. In the isolated hearts subjected to ischemia/reperfusion, the rats fed with modified tomato exhibited better cardiac performance, reduced myocardial infarct size and decreased number of apoptotic cardiomyocytes, and reduced oxidative stress compared to unmodified tomato or resveratrol alone indicating superior cardioprotective abilities of modified tomatoes.


Assuntos
Aciltransferases/genética , Antioxidantes/metabolismo , Miocárdio/patologia , Traumatismo por Reperfusão/patologia , Solanum lycopersicum , Estilbenos/metabolismo , Animais , Apoptose , Dieta , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres/metabolismo , Peroxidação de Lipídeos , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Masculino , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/patologia , Estresse Oxidativo , Plantas Geneticamente Modificadas , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/fisiopatologia , Resveratrol , Estilbenos/uso terapêutico
7.
Drugs Exp Clin Res ; 30(4): 177-81, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15553664

RESUMO

In view of the high concentration of resveratrol found in a new autochthonous wine (Uvalino) and the notable antioxidant activity of this substance, we decided to assess whether this wine could inhibit the production of free radicals. Nowadays, free radicals are considered to be the most noxious factors for tissues, triggering the development of many diseases. The assessments were carried out using a direct and more precise technique, electronic paramagnetic resonance (EPR), which is able to detect the ability of an antioxidant agent to inhibit the formation of hydroxyl radicals (*OH), which are among the most noxious reactive oxygen species (ROS). The results show that Uvalino wine is able to eliminate ROS production almost completely. Consequently, it has beneficial effects on health in all the diseases in which ROS plays an important pathogenetic role.


Assuntos
Radical Hidroxila/antagonistas & inibidores , Radical Hidroxila/metabolismo , Vinho/análise , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/farmacologia , Óxidos N-Cíclicos/química , Óxidos N-Cíclicos/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Radical Hidroxila/química , Ferro/química , Ferro/metabolismo , Ferro/farmacologia , Medicina Tradicional , Resveratrol , Detecção de Spin/métodos , Estilbenos/análise , Estilbenos/química , Estilbenos/farmacologia
8.
Drugs Exp Clin Res ; 30(3): 111-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15366787

RESUMO

The ability of two samples of red wine with different resveratrol concentrations to inhibit hydroxyl radicals (*OH) produced by a Fenton-type reaction was assessed using the method of electronic paramagnetic resonance (EPR). One sample was an autochthonous wine, Uvalino, which has a very high resveratrol concentration; the second was another red wine with a much lower resveratrol concentration. The ability of the sample of Uvalino wine to obstruct hydroxyl radicals was evident, but it wasn't much better than the ability of the sample of wine with a lower resveratrol concentration. The resveratrol concentration of wine is an important factor for the inhibition of the formation of free radicals, especially hydroxyl radicals; however, it is not the only one responsible for this property of wine. Resveratrol concentration can act synergically with other factors, such as polyphenols, which are also contained in wine and have antioxidant properties.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Radicais Livres/antagonistas & inibidores , Estilbenos/análise , Vinho/análise , Sinergismo Farmacológico , Flavonoides/análise , Flavonoides/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Radicais Livres/efeitos adversos , Radicais Livres/análise , Itália , Fenóis/análise , Fenóis/farmacologia , Polifenóis , Resveratrol , Estilbenos/farmacologia , Vitis/química , Vitis/classificação , Vinho/classificação
9.
Drugs Exp Clin Res ; 29(3): 95-100, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14708454

RESUMO

The antioxidant activity of a novel series of derivatives with a carotenoid-like structure was studied. These derivatives have recently been isolated chemically as a result of studies on the pigments present in a particular species of birds, namely parrots. These novel derivatives, which are also called parrodienes, have been proved to possess interesting biological properties that differ from those that carotenoids are known to have. The objective of this study was to demonstrate the ability of these novel compounds to inhibit the formation of reactive oxygen species, especially their ability to block the formation of hydroxyl radicals, which are among the most reactive products of oxygen reactions and which produce the greatest damage to cells and tissues. The technique used to assess this antioxidant capacity of parrodienes was electron paramagnetic resonance, which allows direct assessment of inhibition of hydroxyl radical formation (.OH). The results show that these derivatives, especially octatriene, are able to exert evident antioxidant activity, thus confirming that their antioxidant properties are important for their biological activity.


Assuntos
Antioxidantes/farmacologia , Carotenoides/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Aldeídos/química , Aldeídos/metabolismo , Aldeídos/farmacologia , Animais , Antioxidantes/metabolismo , Carotenoides/metabolismo , Óxidos N-Cíclicos/química , Óxidos N-Cíclicos/metabolismo , Ciclodextrinas/química , Ciclodextrinas/metabolismo , Ciclodextrinas/farmacologia , Avaliação Pré-Clínica de Medicamentos , Sequestradores de Radicais Livres/antagonistas & inibidores , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/metabolismo , Peróxido de Hidrogênio , Radical Hidroxila/antagonistas & inibidores , Radical Hidroxila/química , Radical Hidroxila/metabolismo , Ferro , Papagaios , Polienos/metabolismo , Polienos/farmacologia , Espécies Reativas de Oxigênio/metabolismo
10.
J Eur Acad Dermatol Venereol ; 14(1): 35-45, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10877250

RESUMO

BACKGROUND: The role of elective lymph node dissection in the treatment of patients with primary melanoma is a debated topic in surgical oncology. However, recent data assure a survival improvement with this technique only for patients harbouring nodal metastases. The emergence of a new procedure of lymphatic mapping permits the identification of the sentinel lymph node (SLN), the first draining node from the site of cutaneous melanoma, which has demonstrated to be predictive of staging of the entire regional lymphatic basin and useful in selecting for lymph node dissection only those patients who have early micrometastases. OBJECTIVES: To verify in a large series of cases whether a combination of preoperative lymphoscintigraphy and intraoperative mapping with both vital blue dye and a hand-held gamma probe would permit an increase of the rate of successful SLN localization up to 100%; to check the utility of a wider application of SLN biopsy in patients with thin melanomas owing to a favourable risk-benefit ratio; to determine the predictive value of SLN biopsy by performing regional lymphadenectomy in patients who have pathological evidence of metastases in the SLN; to observe whether the use of SLN technique and selective lymphadenectomy might improve the clinical evolution of patients and favour low rates of recurrence. METHODS: In 425 AJCC stage I or II melanoma patients, preoperative lymphoscintigraphy by intracutaneous injection of Tc99m-labelled albumin nanocolloids around the tumour or the tumour's excision scar was combined with the intraoperative use of a hand-held gamma probe and patent blue V mapping technique, in order to identify and harvest the SLN. In five cases the blue dye was voluntarily not used because of previous allergic reactions. In other 25 preliminary cases the procedure was performed using the blue dye alone (10 cases) or combined with a preoperative lymphoscintigraphy (15 cases). A wide excision of the primary site was then undertaken in all cases. SLNs were sent to the pathologist for serial sectioning and permanent preparations with histological and immunohistochemical examination. Patients with pathological evidence of metastatic disease in SLN returned for regional lymphadenectomy. RESULTS: The combined use of lymphoscintigraphy, blue dye and gamma probe allowed us to identify one or more SLNs in all cases except for two (99.5% rate of success). In 70 melanomas less than 0.76 mm thick, SLNs were negative for metastases, whereas in 380 patients with thicker tumours micrometastases were demonstrated in 75 cases (19.7%). In patients with SLN metastases who underwent regional lymph node dissection, no other metastases were found three times out of four. After a median follow-up period of 18 months the rate of recurrence of the disease in 335 patients with SLN free of metastasis was low (5.4%) with a very low regional nodal recurrence (1.2%). Moreover, the worsening of the disease did not exceed 18.5% of cases with metastasis in SLN. CONCLUSIONS: Our data confirm in a large series of cases that the SLN biopsy is extremely selective and useful to find early micrometastases and to identify patients needing regional lymphadenectomy and adjuvant immunotherapy. Patients with intermediate thickness melanoma (0.76-4.0 mm) should be informed on the availability of such a revolutionary procedure, which represents a new opportunity in primary melanoma surgery.


Assuntos
Melanoma/patologia , Biópsia de Linfonodo Sentinela/métodos , Neoplasias Cutâneas/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Árvores de Decisões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
J Exp Clin Cancer Res ; 18(1): 69-74, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10374681

RESUMO

Sentinel node biopsy allows an accurate selection of melanoma patients to be submitted to therapeutic dissection. From February 1994 to August 1998, at the National Cancer Institute, S. Pio X Hospital in Milan and Bufalini Hospital in Cesena, 580 sentinel node biopsies were performed in 540 stage I melanoma patients (242 males; 298 females; median age 47). Primary melanoma was located in the trunk in 201 patients, in lower limbs in 242 cases, in upper limbs in 80 cases and in head and neck in 17 patients. Injection of blue dye for sentinel node identification was performed in all cases; 372 patients were submitted to preoperative lymphoscintigraphy and in 272 cases an intraoperatory probe for a radioguided biopsy was utilized. Sentinel node identification rate was 91%. Sentinel node positivity rate was 15%. Frozen sections were examined in 199 cases. Distribution of positive cases according to primary thickness is the following: <1 mm: 1%; 1-1.99 mm: 5%; 2-2.99 mm: 18% and > or =3 mm: 27%. Sentinel node appeared to be the only metastatic node in 77% of patients submitted to dissection. The adoption of preoperative lymphoscintigraphy and the intraoperative use of the gamma probe contributed substantially in S.N. identification. No complications caused by the procedure were reported. Eight patients had a regional node relapse after a negative sentinel node biopsy and were submitted to therapeutic distant dissection. Currently 513 patients are alive with no evidence of disease. Present data confirm the feasibility and safety of sentinel node technique for selection of patients to be submitted to radical node dissection and to eventual adjuvant treatments.


Assuntos
Excisão de Linfonodo , Linfonodos/patologia , Melanoma/patologia , Melanoma/cirurgia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/métodos , Criança , Feminino , Humanos , Excisão de Linfonodo/métodos , Linfonodos/diagnóstico por imagem , Masculino , Melanoma/diagnóstico por imagem , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cintilografia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico por imagem
12.
Pathologica ; 91(4): 242-8, 1999 Aug.
Artigo em Italiano | MEDLINE | ID: mdl-10630072

RESUMO

Pathologic evaluation of sentinel lymph node represents a new technique for managing high-risk primary melanoma. We examined the sentinel lymph node biopsies of 200 patients affected by primary melanomas of trunk, limbs, head and neck, who had been operated at "M. Bufalini" Hospital between April 1996 and July 1998. The lymphatic mapping has been performed through the preoperative intradermal injection of vital blue dye and technetium-labelled albumin. 319 sentinel lymph nodes were harvested and the 11.3% (15% of patients) were positive for melanoma metastases. No metastases were found in melanomas < or = 1 mm. The percentage of positive sentinel lymph nodes in patients with melanomas > 1 mm in thickness was 16.3% (22% of patients). In 5 cases (2.5%) nodal nevi were found, 1 of which was associated with micrometastasis. All 30 patients with positive sentinel lymph nodes underwent regional lymph node dissection and 555 lymph nodes were harvested. Melanoma metastases were found in only 7 patients, in 31 lymph nodes. The procedure of SLN detection and biopsy is a feasible surgical approach to melanoma patients. It is extremely useful in finding early metastases and in effective pathologic staging. As a consequence of the very low incidence of metastases in the sentinel lymph nodes of patients with thin melanomas, we suggest the sentinel lymph node mapping should be offered to patients with primary melanomas at least 1 mm in depth.


Assuntos
Linfonodos/patologia , Melanoma/patologia , Melanoma/secundário , Neoplasias Cutâneas/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Excisão de Linfonodo , Metástase Linfática , Masculino , Pessoa de Meia-Idade
13.
Mycopathologia ; 144(1): 1-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10422267

RESUMO

Human serum at 5 to 10% (v/v) in tissue culture medium RPMI-1640, inhibits the growth of Cryptococcus neoformans by 80 to 93%. Serum fractionated on molecular sieve columns (Sephadex G-200) yielded an active protein fraction. This fraction at 100 micrograms protein/ml inhibited the growth of C. neoformans by 54%. When an active G-200 fraction was applied to a dye affinity column (Affi-Gel Blue) the fraction with inhibitory activity was bound by the column and was eluted with 1.4 M NaCl in 0.1 M phosphate buffer (pH 7.4). The bound fraction at 62.5 micrograms protein/ml inhibited C. neoformans growth by 82%. On native polyacrylamide gel electrophoresis (Nu-PAGE) the bound fraction migrated as a major and a minor band. Under the reducing conditions of sodium dodecyl sulfate (SDS)-PAGE the bound fraction yielded 4 prominent bands with MW ranging from 175 kDa to 45 kDa. Purification of the active Sephadex G-200 peak was achieved using an anion exchange column (DEAE-Sephacel). Protein eluted with 0.1 M NaCl had strong anticryptococcal activity (12.5 micrograms/ml, 79% inhibition), which in SDS-PAGE migrated as a single band with an approximate MW of 85 kDA. This protein appears important in natural host resistance to C. neoformans and polymorphisms or deficiencies may have epidemiologic and diagnostic relevance.


Assuntos
Antifúngicos/farmacologia , Proteínas Sanguíneas/isolamento & purificação , Proteínas Sanguíneas/farmacologia , Cryptococcus neoformans/efeitos dos fármacos , Antifúngicos/química , Antifúngicos/isolamento & purificação , Proteínas Sanguíneas/química , Cromatografia em Gel , Cromatografia por Troca Iônica , Cryptococcus neoformans/crescimento & desenvolvimento , Meios de Cultura , Eletroforese em Gel de Poliacrilamida , Humanos
14.
Diagn Cytopathol ; 17(4): 295-7, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9316787

RESUMO

Two cases of an unusual finding of capsular pseudoinvasion in follicular thyroid adenomas after fine-needle aspiration (FNA) procedures are reported. These capsular breaches were noted along the hemorrhagic needle track, which traversed the normal peripheral thyroid parenchyma into the lesions. A reparative reaction was seen at some points along one of the tracks. Histologic examination also showed extrusion of the tumor parenchyma through the capsular interruption in one case. Surgical pathologists should be aware of this rare complication of FNA of thyroid follicular adenomas as a differential diagnosis of minimally invasive (encapsulated) follicular carcinoma.


Assuntos
Adenoma/patologia , Biópsia por Agulha/efeitos adversos , Neoplasias da Glândula Tireoide/patologia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica
17.
Med Microbiol Immunol ; 185(3): 131-7, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9007817

RESUMO

A mixed infection with either rotavirus or poliovirus and Listeria monocytogenes was analysed in Caco-2 cells, a tumour-derived cell line, highly susceptible to these pathogens. The multiplication of these pathogens, whose usual site of entry and/or replication is the intestine, was also followed by electron microscopy. Results obtained showed an increase of L. monocytogenes internalisation in cells infected with rotavirus, whereas the preinfection with poliovirus had only a slight interfering effect on bacterial entry. Analysis of L. monocytogenes multiplication in virus-infected cells revealed that rotavirus also promoted bacterial replication, which poliovirus hampered replication. Concerning the effect of Caco-2 cell invasion by L. monocytogenes on viral replication, we observed an increase in rotavirus antigen synthesis but no significant effect on poliovirus yield under our experimental conditions.


Assuntos
Listeria monocytogenes/fisiologia , Poliovirus/fisiologia , Rotavirus/fisiologia , Células CACO-2 , Humanos , Microscopia Eletrônica , Microscopia de Fluorescência , Replicação Viral
18.
Pediatr Infect Dis J ; 15(10): 876-83, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8895919

RESUMO

BACKGROUND: Infectious diarrheal diseases remain an important cause of childhood morbidity in industrialized countries. The knowledge of the etiology and epidemiology of childhood diarrhea in a given area is needed to plan any measure designed to prevent or ameliorate diarrheal illness and to develop practice guidelines for the most appropriate stool examination procedures. METHODS: We evaluated 618 children with diarrhea and 135 controls prospectively for viral, bacterial and parasitic enteric pathogens. Diarrheagenic Escherichia coli was identified by gene probes specific to different virulence factors. Stool filtrates were examined for the presence of free bacterial toxins by a cell culture cytotoxicity assay. Clinical and epidemiologic data were recorded and analyzed in relation to microbiologic findings. RESULTS: Enteropathogens were identified in 59% of children with diarrhea and in 10.4% of asymptomatic controls. The agents mainly associated with disease were rotavirus (23.6%), Salmonella (19.2%) and Campylobacter (7.9%). Rotavirus was significantly more frequent among children observed as inpatients whereas Campylobacter was significantly more common in outpatients. Infections with diarrheagenic E. coli, Shigella flexneri, yersinia enterocolitica, Cryptosporidium and Giardia were observed in a limited number of patients. The clinical presentation of children was not sufficiently characteristic to permit presumptive diagnosis of a specific pathogen. conversely the presence of blood and/or leukocytes in stools had a high positive predictive value for Salmonella or Campylobacter infection. CONCLUSION: The results of this study will be useful for planning strategies to prevent and control diarrheal diseases in our country.


Assuntos
Doenças Transmissíveis/epidemiologia , Diarreia/microbiologia , Criança , Pré-Escolar , Doenças Transmissíveis/microbiologia , Diarreia/epidemiologia , Fezes/microbiologia , Humanos , Lactente , Itália/epidemiologia , Técnicas Microbiológicas , Estudos Prospectivos
19.
J Med Microbiol ; 44(6): 418-24, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8636958

RESUMO

To evaluate the role of the acidic pH of phagosomes on the invasive ability and fate of Listeria monocytogenes within host cells, entry and replication of this gram-positive bacterium in a human enterocyte-like cell line (Caco-2) were investigated by a combination of biochemical and ultrastructural approaches. The effects of inhibitors of vacuolar acidification--the lipophilic weak base ammonium chloride, the carboxylic ionophore monensin and the vacuolar proton ATPase inhibitor bafilomycin A1--on the bacterial invasion pathway were analysed. These agents, which raise the intracellular vesicle acidic pH of living cells by different mechanisms, affected L. monocytogenes replication in Caco-2 cells. Bacteria internalised by bafilomycin-treated cells were unable to escape from phagosomes, as demonstrated by electronmicroscopy. The results provide evidence that low pH is required for efficient intracellular growth of L. monocytogenes.


Assuntos
Células CACO-2/microbiologia , Listeria monocytogenes/fisiologia , Macrolídeos , Fagossomos/microbiologia , Vacúolos/metabolismo , Cloreto de Amônio/farmacologia , Antibacterianos/farmacologia , Células CACO-2/efeitos dos fármacos , Células CACO-2/ultraestrutura , Inibidores Enzimáticos/farmacologia , Células HeLa/microbiologia , Humanos , Concentração de Íons de Hidrogênio , Ionóforos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Microscopia Eletrônica , Monensin/farmacologia , Fagossomos/efeitos dos fármacos , Fagossomos/ultraestrutura , ATPases Translocadoras de Prótons/antagonistas & inibidores , Vacúolos/efeitos dos fármacos , Vacúolos/ultraestrutura
20.
J Clin Microbiol ; 34(3): 689-94, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8904439

RESUMO

Fifty-five Escherichia coli strains belonging to enteropathogenic E. coli (EPEC) serogroups were examined for phenotypic and genetic factors associated with virulence. The strains were isolated in Italy from children with diarrhea and identified as EPEC by clinical laboratories using commercially available antisera. O:H serotyping showed that 35 strains (27 of O26, O111, and O128 serogroups) belonged to 11 serotypes considered to be classical EPEC O:H serotypes. The other 20 isolates were classified as 15 nonclassical EPEC O:H serotypes. All the potential EPEC virulence factors associated with bacterial adhesion (localized adherence, fluorescentactin staining test positivity, presence of the attaching and effacing [eaeA] gene), the production of verotoxin, and the positivity with the enterohemorrhagic E. coli probe were significantly more frequent among isolates belonging to classical than nonclassical serotypes. Strains displaying an aggregative adhesion and hybridizing with the enteroaggregative DNA probe were found in serogroups O86, O111, and O126. Verotoxin-producing isolates belonged to serogroups O26, O111, and O128. Only one of the isolates hybridized with the EPEC adherence factor (EAF) probe, but 33 strains gave positive results with the eae probe, confirming that the former is more suitable in epidemiological studies in European countries. These results indicate that up to 75% of strains identified as EPEC by commercial antisera may possess potential virulence properties and/or belong to classical EPEC O:H serotypes and suggest that O grouping is still a useful diagnostic tool for presumptive identification of diarrheagenic E. coli in clinical laboratories.


Assuntos
Adesinas Bacterianas , Proteínas de Transporte , Diarreia/microbiologia , Proteínas de Escherichia coli , Escherichia coli/patogenicidade , Proteínas da Membrana Bacteriana Externa/genética , Criança , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Humanos , Plasmídeos , Sorotipagem , Virulência
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