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1.
Int J Immunopathol Pharmacol ; 26(1 Suppl): 33-41, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24046947

RESUMO

Many strategies, including those based on genetically modified Mesenchymal Stromal Cells (MSCs), have been developed in recent years in order to obtain high concentrations of anticancer drugs effective on tumor mass. In previous studies, we showed that human and murine bone marrow-derived MSCs (BM-MSCs) and human skin-derived stromal fibroblasts (hSDFs) acquired strong anti-tumor capacity, both in vitro and in vivo, once primed with Paclitaxel (PTX). In this report we investigate whether adipose tissue-derived MSCs (AT-MSCs) behave similarly to BM-MSCs in their uptake and release of PTX in sufficient amounts to inhibit tumor proliferation in vitro. According to a standardized procedure, PTX primed AT-MSCs (AT-MSCsPTX) were washed and then subcultured to harvest their conditioned medium, which was then tested to evaluate its in vitro anti-tumor potential. We observed that AT-MSCsPTX were able to uptake PTX and release it in a time-dependent manner and that the released drug was active in vitro against proliferation of leukemia, anaplastic osteosarcoma, prostatic carcinoma and neuroblastoma cell lines. These data confirm that AT-MSCs, as well as BM-MSCs, can be loaded in vitro with anti-cancer drugs. While the harvesting of BM-MSCs requires invasive procedures, AT-MSCs can be prepared from fat samples taken with little patient discomfort. For this reason, this source of stromal cells represents an important alternative to BM-MSCs in developing new tools for carrying and delivering anti-cancer drugs into tumor microenvironments.


Assuntos
Tecido Adiposo/citologia , Antineoplásicos Fitogênicos/farmacologia , Células-Tronco Mesenquimais/metabolismo , Paclitaxel/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos
2.
Pathol Biol (Paris) ; 60(5): 287-90, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22867954

RESUMO

Schistosoma haematobium plays a central role in the development of bladder cancer in Burkina Faso. The objective of this study was to determine the presence of S. haematobium in the bladder cancer and in vector snails. For the first time, formalin-fixed tissues embedded in paraffin were analyzed by immunohistochemistry and PCR. Molecular detection has resulted in 7/7 positive bladder cancer. Finally, as the snail vectors were positive. We suggest the use of molecular methods in the snail vectors for the detection of cysts and in cancerous tissues in larger studies.


Assuntos
Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/parasitologia , Oocistos/patologia , Schistosoma haematobium/isolamento & purificação , Esquistossomose Urinária/complicações , Caramujos/parasitologia , Neoplasias da Bexiga Urinária/etiologia , Neoplasias da Bexiga Urinária/parasitologia , Animais , Burkina Faso , Vetores de Doenças , Ovos , Humanos , Schistosoma haematobium/genética , Schistosoma haematobium/metabolismo , Esquistossomose Urinária/parasitologia
3.
Eur J Histochem ; 56(2): e12, 2012 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-22688293

RESUMO

Fixation is a critical step in the preparation of tissues for histopathology. The objective of this study was to investigate the effects of different fixatives vs formalin on proteins and DNA, and to evaluate alternative fixation for morphological diagnosis and nucleic acid preservation for molecular methods. Forty tissues were fixed for 24 h with six different fixatives: the gold standard fixative formalin, the historical fixatives Bouin and Hollande, and the alternative fixatives Greenfix, UPM and CyMol. Tissues were stained (Haematoxylin-Eosin, Periodic Acid Schiff, Trichromic, Alcian-blue, High Iron Diamine), and their antigenicity was determined by immunohistochemistry (performed with PAN-CK, CD31, Ki-67, S100, CD68, AML antibodies). DNA extraction, KRAS sequencing, FISH for CEP-17, and flow cytometry analysis of nuclear DNA content were applied. For cell morphology the alternative fixatives (Greenfix, UPM, CyMol) were equivalent to formalin. As expected, Hollande proved the best fixative for morphology. The morphology obtained with Bouin was comparable to that with formalin. Hollande was the best fixative for histochemistry. Bouin proved equivalent to formalin. The alternative fixatives were equivalent to formalin, although with greater variability in haematoxylin-eosin staining. It proved possible to obtain immunohistochemical staining largely equivalent to that following formalin-fixation with the following fixatives: Greenfix, Hollande, UPM and CyMol. The tissues fixed in Bouin did not provide results comparable to those obtained with formalin. The DNA extracted from samples fixed with alternative fixatives was found to be suitable for molecular analysis.


Assuntos
Alendronato/farmacologia , Conservadores da Densidade Óssea/farmacologia , Fixadores/farmacologia , Histocitoquímica/métodos , Côndilo Mandibular/ultraestrutura , Microscopia Eletrônica de Transmissão/métodos , Animais , Matriz Extracelular , Proteínas da Matriz Extracelular/metabolismo , Feminino , Formaldeído/farmacologia , Masculino , Côndilo Mandibular/metabolismo , Proteoglicanas/metabolismo , Ratos , Ratos Wistar
4.
Int J Clin Pract ; 61(8): 1270-7, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17590218

RESUMO

OBJECTIVE: This study was designed to investigate the analgesic effects of nimesulide and celecoxib in patients with knee osteoarthritis (OA). In patients with joint effusion, the effects of these non-steroidal anti-inflammatory drugs (NSAIDs) on synovial fluid concentrations of substance P (SP), interleukin (IL)-6 and IL-8 also were evaluated. METHODS: Patients were randomly assigned either nimesulide (100 mg twice a day) or celecoxib (200 mg once a day) for 2 weeks. The intensity of joint pain was assessed with a 100-mm visual analogue scale (VAS). Furthermore, patients completed questions about analgesic efficacy and overall tolerability of the treatments on a five-point categorical scale. Synovial fluid samples were drawn at baseline, 30 min after the first drug intake (day 1), and 30 min after the last drug intake (day 14). RESULTS: We enrolled 44 patients, 20 of whom had a joint effusion. In this group, the effects of nimesulide were more marked than for celecoxib, with evidence of a faster onset of the analgesic action. Both after a single or repeated administration, nimesulide significantly reduced the synovial fluid concentrations of SP and IL-6. Celecoxib, on the other hand, did not change the concentrations of SP and significantly reduced the levels of IL-6 only on day 14. None of the drugs affected IL-8. Both drugs were generally well tolerated. CONCLUSIONS: These results provide evidence that nimesulide is an effective agent for the symptomatic treatment of OA. The effect on inflammatory pain mediators is consistent with the fast analgesic action of this NSAID.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Artralgia/tratamento farmacológico , Osteoartrite do Joelho/tratamento farmacológico , Pirazóis/uso terapêutico , Sulfonamidas/uso terapêutico , Idoso , Celecoxib , Método Duplo-Cego , Feminino , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Masculino , Medição da Dor , Substância P/metabolismo , Líquido Sinovial/química , Resultado do Tratamento
5.
J Int Med Res ; 34(4): 348-54, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16989489

RESUMO

The aim of this study was to evaluate plasma and synovial fluid concentrations of the non-steroidal anti-inflammatory drug nimesulide and its major metabolite (hydroxynimesulide, M1), after a single 100 mg dose of nimesulide and a repeated (14 day) administration, 100 mg twice a day, in patients with osteoarthritis of the knee and joint effusion. Nimesulide was rapidly absorbed in plasma and distributed in synovial fluid. On day 1, effective concentrations were present 30 min after the first dose and on day 14, the synovial fluid concentration of nimesulide was significantly higher than that measured on day 1; no accumulation was observed in plasma. After 14 days of treatment, both the plasma and synovial fluid concentrations of M1 were significantly higher than those measured on day 1. These data may help to explain the rapid onset of the analgesic effect of nimesulide demonstrated in several clinical conditions, including painful osteoarthritis.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Osteoartrite do Joelho/metabolismo , Sulfonamidas/metabolismo , Sulfonamidas/farmacocinética , Líquido Sinovial/metabolismo , Administração Oral , Idoso , Anti-Inflamatórios não Esteroides/sangue , Feminino , Humanos , Masculino , Sulfonamidas/análise , Sulfonamidas/sangue , Líquido Sinovial/química
6.
Eur J Histochem ; 49(1): 53-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15823795

RESUMO

A novel application of fluorescence in situ hybridization (FISH) to isolated nuclei is described. The method detects gene amplification and chromosome aneuploidy in extracted nuclei from paraffin-embedded tissue of human cancer with greater sensitivity and specificity than existing FISH methods. In this study, the method is applied to signal detection of the HER-2/neu (c-erbB-2) gene, whose amplification is one of the most common genetic alterations associated with human breast cancer. Nuclei were extracted and isolated from formalin fixed, paraffin embedded tissue of 43 different carcinomas (breast, ovary, endometrium, gastrointestinal stromal tumor and malignant mesothelioma). FISH was performed both on sections and extracted nuclei of each tissue using chromosome enumeration probes (CEP) for the centromeric regions of chromosomes 8 and 17, and a locus specific identifier (LSI) for the HER-2/neu oncogene. Differences between ploidy calculated in sections and extracted nuclei were seen in 3 breast carcinomas and 1 gastrointestinal stromal tumor (GIST). Furthermore, 1 breast cancer, previously considered to be borderline for HER-2/neu gene amplification turned out to be clearly amplified. Nuclei extraction and isolation bypass all the problems related to signal interpretation in tissue sections, and the adoption of this new technique, which improves the signal quality in several neoplastic samples, is suggested.


Assuntos
Aneuploidia , Carcinoma/genética , Núcleo Celular/genética , Amplificação de Genes/genética , Hibridização in Situ Fluorescente/métodos , Neoplasias/genética , Inclusão em Parafina , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma/patologia , Núcleo Celular/patologia , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Feminino , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Genes erbB-2/genética , Humanos , Mesotelioma/genética , Mesotelioma/patologia , Neoplasias/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Fixação de Tecidos/métodos
7.
Int Immunopharmacol ; 3(13-14): 1901-8, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14636839

RESUMO

Both the analgesic drugs tramadol and paracetamol are widely used for the symptomatic therapy of osteoarthritis (OA). The aim of this double-blind, randomised study in patients with knee OA was to compare their effects on synovial fluid concentrations of interleukin (IL)-6 and substance P (SP). Moreover, we evaluated plasma and synovial fluid concentrations of tramadol and its active metabolite (O-desmethyl-tramadol, M1) after oral treatment with this drug. Twenty patients were enrolled. A group of 10 patients received tramadol (50 mg three times a day), and another group of 10 patients were treated with paracetamol (500 mg three times a day) for 7 days. Both drugs significantly reduced the intensity of joint pain. The synovial fluid concentrations of SP were significantly reduced only by the treatment with tramadol. In this group of patients, IL-6 synovial fluid concentrations were slightly, but not significantly, decreased. Paracetamol did not significantly change the synovial fluid concentrations of SP and IL-6. After oral administration, a considerable amount of tramadol was measurable in synovial fluid. Both in plasma and synovial fluid the concentrations of M1 were markedly lower than those of tramadol, with a T/M1 ratio of 14.7+/-4.6 and 9.3+/-3.9, respectively. These data demonstrate that the activity of tramadol may involve the modulation of inflammatory mediators. Moreover, they indicate that after oral treatment with tramadol, both the parent drug and its active metabolite can penetrate into synovial fluid.


Assuntos
Acetaminofen/farmacologia , Interleucina-6/química , Osteoartrite do Joelho/tratamento farmacológico , Substância P/química , Líquido Sinovial/química , Tramadol/análogos & derivados , Tramadol/farmacologia , Acetaminofen/metabolismo , Acetaminofen/uso terapêutico , Administração Oral , Idoso , Método Duplo-Cego , Feminino , Humanos , Interleucina-6/imunologia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/fisiopatologia , Dor/tratamento farmacológico , Dor/etiologia , Medição da Dor , Estudos Prospectivos , Substância P/efeitos dos fármacos , Substância P/fisiologia , Líquido Sinovial/efeitos dos fármacos , Líquido Sinovial/metabolismo , Fatores de Tempo , Tramadol/metabolismo , Tramadol/uso terapêutico
8.
Eur Urol ; 43(6): 680-5, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12767370

RESUMO

OBJECTIVES: The Heidelberg classification of renal tumours identifies five histotypes of renal cancer, underlining for two of them (conventional and papillary renal cancers) a strict relation between the morphological aspect and the complement of alterations evidenced by the cytogenetic analysis of the neoplastic karyotype. Due to its low incidence, the collecting duct carcinoma (CDC) has not yet been characterized from a cytogenetic point of view. This study analyses the clinical, morphologic and cytogenetic features of the CDC observed and treated in our department. METHODS: From January 1995 to December 2002, among the 591 patients who underwent surgery for renal cancer, we observed 11 cases of CDC (prevalence 1.9%) treated either by radical (9 cases) or partial nephrectomy (2 cases). During radical nephrectomy a loco-regional lymphadenectomy was always performed. In the 9 cases observed after 1997, a complete cytogenetic analysis of the neoplastic karyotype was carried out. RESULTS: At pathological examination the disease was found to be confined to the renal capsule (TNM 1997 stage 1) in only 3 patients; venous neoplastic trombosis and nodal metastasis were present in 3 and 6 cases respectively; 2 patients showed distant metastases (lung, bone). Two of the patients affected with stage 1 tumours are still alive with no evidence of the disease at 48 and 88 months after surgery, while the third died following the systemic progression of a concomitant bladder carcinoma. One patient with stage 4 tumour (no. 11) is alive, but the follow up time is still limited (2 months). All the other 7 patients are dead after a mean survival time of 16.3 months (range 0-45). As for cytogenetic analysis, 2 CDCs didn't grow in culture and in one case no karyotype alterations were reported. In the remaining 6 cases hypodiploid stemlines and a homogeneous chromosome alteration pattern were observed, with multiple numerical and structural aberrations (mean 11.1, range 7-15) and the continuous involvement of chromosomes 1 and X or Y, both as traslocation and deletion/monosomy. Additional abnormalities of chromosomes 22 and 13 were found to be common but less frequent. CONCLUSIONS: The clinical behaviour of the CDC is aggressive and its prognosis is surely poor; surgical treatment seems to be curative only for organ-confined cancer, accounting for the minority of cases. This neoplasm is cytogenetically characterized by hypodiploid stemlines with common involvement of chromosome 1 and the autosomes.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Túbulos Renais Coletores , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/epidemiologia , Carcinoma de Células Renais/genética , Análise Citogenética , Feminino , Humanos , Itália/epidemiologia , Cariotipagem , Neoplasias Renais/epidemiologia , Neoplasias Renais/genética , Masculino , Pessoa de Meia-Idade , Prevalência
9.
Reumatismo ; 54(3): 251-6, 2002.
Artigo em Italiano | MEDLINE | ID: mdl-12404034

RESUMO

OBJECTIVE: To evaluate if parenteral gold-therapy with Sodium gold thiosulfate is effective and safe for the treatment of rheumatoid arthritis we began an open, multicenter trial. METHODS: 126 rheumatoid arthritis patients were treated with Sodium gold thiosulfate for two years. Efficacy, quality of life, progression of joint damage, inflammatory parameters and side effects were evaluated. RESULTS: Gold salts reduced joint inflammation and improved subjective and objective symptoms, quality of life and activity of illness within 6 months. Side effects appeared in 13,8% of all cases and regressed, promptly, when gold therapy stopped. The poor efficacy caused the interruption and the change from the gold therapy to others disease-modifying anti-rheumatic drugs (DMRDs) in 17,8 % of the patients. CONCLUSIONS: The follow-up showed Sodium gold thiosulfate was effective in Rheumatoid Arthritis and the survival in therapy was of 77,8% to one year and of 68,4% to two years.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Tiossulfato Sódico de Ouro/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Progressão da Doença , Toxidermias/etiologia , Feminino , Seguimentos , Tiossulfato Sódico de Ouro/administração & dosagem , Tiossulfato Sódico de Ouro/efeitos adversos , Humanos , Nefropatias/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Segurança , Índice de Gravidade de Doença
10.
Minerva Med ; 93(3): 199-202, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12094150

RESUMO

BACKGROUND: In the evaluation of functional status of patients with rheumatoid arthritis (RA) the health related quality of life is currently considered important because of its approach to various components of life, such as social, psychological, and physical aspects. We used the Stanford Health Assessment Questionnaire (HAQ) to assess the improvement of functional status in patients with RA treated with gold salts. METHODS: In a prospective investigation 91 patients with RA in anatomical stage I, II, or III, 66 females and 25 males, with a mean age of 53.17 years, were evaluated during medical treatment in a 1-year follow-up. The treatment consisted in sodium aureothiosulphate, plus corticosteroids and NSAID. The assessments were done during ambulatory visits, at baseline and after 6 and 12 months of treatment, by HAQ as well as by other parameters such as Ritchie Index, visual analog scale (VAS), and morning stiffness. A group of 19 RA patients included by the same criteria and treated only by corticosteroids and NSAID was used as control for the first 6 months of the study. RESULTS: HAQ scores and other parameters were significantly lower (p=0.0001) at the 6th and 12th month measurements when compared with baseline. In the control group only a significant difference in the VAS score was detected. CONCLUSIONS: All the parameters measured in our study were useful in detecting clinical improvement in RA patients treated with sodium aureothiosulphate plus corticosteroids and NSAIDs, but the HAQ provides a more global assessment of the patient's status.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Qualidade de Vida , Corticosteroides/uso terapêutico , Adulto , Idoso , Anti-Inflamatórios não Esteroides/uso terapêutico , Antirreumáticos/uso terapêutico , Feminino , Tiossulfato Sódico de Ouro/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
11.
Cancer Genet Cytogenet ; 116(1): 54-8, 2000 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-10616534

RESUMO

A previously undescribed combination of cytogenetic abnormalities was detected in two renal cell tumors, one eosinophilic variant of the chromophilic type of renal cell carcinoma, and one oncocytoma. Both tumors shared loss of 1p material and monosomy 18. These complex changes, while being unusual, indicate that chromosome 1p rearrangements, rather than associated numerical changes, seem to play a crucial role in the development of renal tumors.


Assuntos
Carcinoma de Células Renais/genética , Cromossomos Humanos Par 1 , Neoplasias Renais/genética , Idoso , Carcinoma de Células Renais/patologia , Cromossomos Humanos Par 18 , Eosinófilos/patologia , Feminino , Deleção de Genes , Humanos , Cariotipagem , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Monossomia
12.
Cancer Genet Cytogenet ; 114(2): 117-20, 1999 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-10549267

RESUMO

Cytogenetic investigation was attempted on 44 tumors from 44 patients with transitional cell carcinoma (TCC) of the upper urinary tract (pelvis and ureter), and karyotypes were obtained in 27 tumors. Numerical changes prevailed, but are not specific for this type of tumor (trisomy 7, -Y, or both). In the light of previously reported data on TCC, the finding of a del(9q) as the only anomaly in one of the cases may be meaningful. Patients showing -Y and/or trisomy 7 had a poor prognosis.


Assuntos
Carcinoma de Células de Transição/genética , Aberrações Cromossômicas/genética , Análise Citogenética , Neoplasias Renais/genética , Pelve Renal , Neoplasias Ureterais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/diagnóstico , Carcinoma de Células de Transição/patologia , Deleção Cromossômica , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 9/genética , Feminino , Humanos , Cariotipagem , Neoplasias Renais/diagnóstico , Neoplasias Renais/patologia , Pelve Renal/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Trissomia/genética , Neoplasias Ureterais/diagnóstico , Neoplasias Ureterais/patologia , Cromossomo Y/genética
14.
Oncol Rep ; 6(2): 295-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10022992

RESUMO

Two new cases of chromophobe renal cell carcinoma were diagnosed on the basis of their morphology and their karyotype complemented by flow cytometry. In one of these cases, however, all these investigations were not sufficient and additional histochemistry investigation had to be used to completely rule out other renal tumors such as oncocytoma, the prognosis of which is totally different.


Assuntos
Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Citometria de Fluxo , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade , Prognóstico
15.
Cancer Genet Cytogenet ; 105(1): 6-10, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9689922

RESUMO

Rearrangements of 3q were found in 10% of a series of 230 cases of renal cell carcinoma (RCC). Together with observations from the literature, these structural changes can be concluded to involve two different regions, 3q21 and 3q11-12, and are usually present as unbalanced translocations. In some of these cases of RCC with the translocation, the normal chromosome 3 may reduplicate, giving rise to a partial trisomy 3q instead of a partial monosomy 3. In those cases, however, histology shows chromophilic-papillary RCC instead of clear cell-nonpapillary. Hence, besides the still unresolved underlying molecular changes causing RCC, histology may in part depend on the presence of partial monosomy or partial trisomy 3.


Assuntos
Adenocarcinoma Papilar/genética , Carcinoma de Células Renais/genética , Deleção Cromossômica , Cromossomos Humanos Par 3/genética , Neoplasias Renais/genética , Monossomia/patologia , Trissomia/patologia , Adenocarcinoma Papilar/diagnóstico , Adulto , Idoso , Carcinoma de Células Renais/diagnóstico , Feminino , Humanos , Cariotipagem , Neoplasias Renais/diagnóstico , Masculino , Pessoa de Meia-Idade
16.
Photochem Photobiol ; 66(3): 374-83, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9297981

RESUMO

Rose bengal, a xanthene derivative among the most efficient producer of singlet oxygen, was submitted to a chemical modification consisting in the introduction of an acetate group into the aromatic ring fluorophore structure. The acetate group acts as a quencher, thus inactivating both fluorescence and photosensitization properties of the molecule. In the modified structure, rose bengal acts as a fluorogenic substrate giving rise to the cellular reaction termed fluorochromasia. The acetate group is recognized by a carboxylic esterase activity that splits it. Removal of the quencher group results in restoring the native structure of photosensitizer inside the cells. The intracellular turnover of rose bengal acetate was studied in rat glioma-derived cultures cells, in terms of the balance of the processes of influx and enzyme hydrolysis of the fluorogenic substrate, and of the efflux of the fluorescent product. A large intracellular accumulation of photosensitizer is obtained when treatments are performed with the fluorogenic substrate, even at the drug concentration at which rose bengal does not enter the cells. The intracellular localization allows rose bengal to exert a more effective photosensitization effect. Provided that the quencher group is selected according to the metabolic properties of the tumor cells, the use of fluorogenic substrates as photosensitizer precursors could improve fluorescence diagnosis and the photodynamic therapy of tumors, exploiting the biological properties that distinguish pathological from normal conditions.


Assuntos
Corantes Fluorescentes/uso terapêutico , Hidrolases/metabolismo , Neoplasias/terapia , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Rosa Bengala/uso terapêutico , Acetilação , Animais , Catálise , Esterases/metabolismo , Corantes Fluorescentes/metabolismo , Hidrólise , Espectroscopia de Ressonância Magnética , Neoplasias/diagnóstico , Ratos , Rosa Bengala/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Células Tumorais Cultivadas
17.
J Photochem Photobiol B ; 30(1): 29-37, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8558361

RESUMO

Autofluorescence has been proved to be an intrinsic parameter of biological substrates that may aid in both the characterization of the physiological state and the discrimination of pathological from normal conditions of cells, tissues and organs. In this work, the fluorescence properties of human white blood cells have been studied in suspension and on single cells at microscopy. The results indicate that suspensions of agranulocytes and granulocytes differ in the amplitude of the fluorescence signal on excitation at wavelengths in the range 250-370 nm. The differences are particularly enhanced when excitation is performed in the 250-265 nm range. Microspectrofluorometric analysis, performed on single cells, allows several leukocyte families to be characterized. Lymphocytes, monocytes, neutrophils and eosinophils can be distinguished according to the intensity and spectral shape of the autofluorescence emission in the visible range from 440 to 580 nm. Both the nature and extent of the differences change when the excitation wavelength is moved from 366 to 436 nm. Differences in the intrinsic metabolic engagement, rather than in the cell dimensions, seem to be responsible for the differences observed between the leukocyte populations. The results identify interesting perspectives for autofluorescence as a discriminating parameter in the differential counting of human white blood cells.


Assuntos
Leucócitos/fisiologia , Fluorescência , Humanos , Processamento de Imagem Assistida por Computador , Microscopia de Fluorescência , Espectrometria de Fluorescência
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