Major determinants of photoinduced cell death: Subcellular localization versus photosensitization efficiency

We present a study on whether and to what extent subcellular localization may compete favorably with photosensitization efficiency with respect to the overall efficiency of photoinduced cell death. We have compared the efficiency with which two cationic photosensitizers, namely methylene blue (MB) and crystal violet (CV), induce the photoinduced death of human cervical adenocarcinoma (HeLa) cells. Whereas MB is well known to generate singlet oxygen and related triplet excited species with high quantum yields in a variety of biological and chemical environments (i.e., acting as a typical type II photosensitizer), the highly mitochondria-specific CV produces triplet species and singlet oxygen with low yields, acting mostly via the classical type I mechanism (e.g., via free radicals). The findings described here indicate that the presumably more phototoxic type II photosensitizer (MB) does not lead to higher degrees of cell death compared to the type I (CV) photosensitizer. In fact, CV kills cells with the same efficiency as MB, generating at least 10 times fewer photoinduced reactive species. Therefore, subcellular localization is indeed more important than photochemical reactivity in terms of overall cell killing, with mitochondrial localization representing a highly desirable property for the development of more specific/efficient photosensitizers for photodynamic therapy applications. (C) 2011 Elsevier Inc. All rights reserved.

Estudo clínico de fase II e farmacocinético para o uso de Talidomida em pacientes com câncer colorretal metastático

O objetivo deste estudo foi avaliar a eficácia, a segurança e a farmacocinética da talidomida nos pacientes com câncer colorretal metastático. Dezessete pacientes com adenocarcinoma colorretal metastático, previamente tratados com pelo menos um regime de quimioterapia, foram incluídos no estudo. Os pacientes eram inicialmente tratados com talidomida 200 mg/dia, com um aumento de dose de 200mg a cada duas semanas, até atingir a dose máxima de 800 mg/dia. Os pacientes eram reavaliados a cada duas semanas para toxicidade e a cada 8 semanas para taxa de resposta através de exames de imagem. A farmacocinética foi caracterizada em quatro pacientes no nível de dose de 200 mg/dia.Todos os dezessete pacientes incluídos foram avaliados no perfil de toxicidade e quatorze pacientes nos critérios de taxa de resposta. A talidomida foi bem tolerada, sendo os principais efeitos colaterais a sonolência, a tontura, a xerostomia e a constipação. Não houve nenhuma resposta objetiva ou doença estável após oito semanas de tratamento. A sobrevida global mediana foi de 3,6 meses. A talidomida é bem tolerada como agente único de tratamento, mas não demonstrou nenhuma atividade antitumoral em pacientes com câncer colorretal metastático, já tratados previamente com outro regime de quimioterapia. Apesar disto, futuros estudos com este agente em estágios iniciais desta neoplasia devem ser considerados, quando as propriedades antiangiogênicas desta droga poderão ser mais relevantes para a progressão da doença.

Estudo da farmacocinética da talidomida em pacientes com tumores sólidos refratários

O objetivo deste estudo foi avaliar os parâmetros farmacocinéticos da talidomida em pacientes com tumores sólidos refratários incluídos em estudo de fase II em nossa Instituição. Foram incluídos 14 pacientes, sendo 5 com diagnóstico de adenocarcinoma de reto, 4 com adenocarcinoma de cólon, 4 com melanoma e 1 com adenocarcinoma de pâncreas. Todos os pacientes foram previamente tratados, 14 com cirurgia, 11 com quimioterapia, 5 com radioterapia e 1 com imunoterapia. Os pacientes foram inicialmente tratados com talidomida 200 mg/dia, com um aumento de dose de 200mg a cada duas semanas, até atingir a dose máxima de 800 mg/dia. Treze pacientes atingiram o nível de 400mg/dia, 9 pacientes os níveis de 600mg/dia e apenas 5 pacientes atingiram 800mg/dia. A farmacocinética foi caracterizada em oito pacientes no nível de dose de 200 mg/dia. Todos os 14 pacientes incluídos foram avaliados quanto ao perfil de toxicidade e resposta antitumoral. A talidomida foi bem tolerada, sendo os principais efeitos colaterais a sonolência, a tontura, a xerostomia e a constipação. Não foram observadas respostas tumorais objetivas. Para avaliar os parâmetros farmacocinéticos da talidomida foram coletadas amostras de sangue imediatamente antes da administração da droga, 1h, 2h, 2,5h, 3h, 3,5h, 4h, 5h, 7h e 24h após a administração da primeira dose de talidomida de 200mg. A determinação das concentrações e parâmetros farmacocinéticos da talidomida nestas amostras foi realizada por cromatografia líquida de alta performance. A curva de decaimento das concentrações plasmáticas obedeceu a um modelo farmacocinético monocompartimental. A média dos principais parâmetros farmacocinéticos estudados foi: Cmax 1,48 ± 0,56μg/ml, Tmax 4,4± 0,5h, ASC 17,7±8,4μg x h/mL e t½ 6,5±3,0 hs. O autor pode concluir que os parâmetros farmacocinéticos da talidomida estudados nestes pacientes foram semelhantes àqueles descritos anteriormente em voluntários sadios, pacientes com HIV, hanseníase ou adenocarcinoma de próstata.

O envolvimento do marcador inflamatório Heme Oxigenêse-1 na carciinogênese experimental de esôfago

Sabe-se que o refluxo crônico pode induzir lesão mucosa, estimular a proliferação de células e promover tumorigênese no esôfago distal. Ainda não é sabido por que apenas uma parcela dos pacientes com refluxo esofágico progrediram para uma metaplasia intestinal (Esôfago de Barrett) e adenocarcinoma. O estresse oxidativo parece exercer um papel importante nessa progressão . Assim sendo, examinamos o padrão de expressão da enzima Heme Oxigenase-1 (HO-1), enzima indutora do estresse oxidativo, em peças de esôfago obtidos de um estudo experimental com ratos que avaliou o papel do refluxo gástrico e duodenoesofágico na carcinogênese esofágica. Métodos: Uma amostra de três (3) peças de esôfago de cada grupo de ratos submetidos a tratamentos diferentes tiveram a expressão da enzima Heme Oxigenase-1 avaliada através de imunohistoquímica. Os ratos foram divididos nos seguintes grupos: (1) cardioplastia para induzir refluxo predominantemente gástrico, (2) anastomose esofagoduodenal para induzir refluxo duodenal, (3) sem tratamento, (4) cardioplastia+dietilnitrosamina (DEN), (5) anastomose esofagoduodenal +DEN, (6) DEN. Resultados: Não houve desenvolvimento de câncer ou metaplasia intestinal nos animais que não foram expostos ao refluxo de conteúdo duodenal. A expressão de HO-1 foi observada apenas em ratos submetidos à anastomose esofagoduodenal (Grupos 2 e 5) e a análise da média de intensidade de fluorescência demonstrou uma diferença significante de expressão de HO-1 (4,8 e 4,6 vezes respectivamente) comparando-se ao controle (Grupo 3) (p<0,05). O alvo principal para expressão da HO-1 foram as células inflamatórias dentro do tumor ou em áreas subepiteleiais. Os ratos expostos ao refluxo gástrico não desenvolveram tumores ou expressaram a HO-1. Conclusões: A esofagite de refluxo induzida por refluxo esofágico com conteúdo duodenal provocou estresse oxidativo considerável e pode desempenhar um papel importante na carcinogênese esofágica. O refluxo gástrico não foi suficiente para induzir estresse oxidativo neste modelo experimental.

Associação do papilomavírus humano com o carcinoma colorretal

OBJETIVO: Investigar a presença do papiloma vírus humano no adenocarcinoma de cólon e reto. MÉTODOS: Setenta e dois pacientes com adenocarcinoma de cólon e reto foram analisados. Foram coletadas duas amostras de cada paciente: uma amostra do tumor e outra de mucosa não neoplásica distante 15 cm do tumor. Como grupo de controle, também foram estudadas amostras de mucosa de quinze pacientes sem câncer colorretal. Os tecidos foram analisados por “auto nested” PCR usando o primer consensus GP5+/GP6+. Dois primers específicos para região E6 dos HPV 16 e HPV 18 também foram utilizados. RESULTADOS: O DNA do HPV foi detectado em tecidos de cólon e reto de 60 pacientes com câncer ( 83 por cento), enquanto que este não foi encontrado em nenhum dos pacientes controles sem tumor ( p<0,001). Em vinte e três pacientes, o DNA do HPV estava presente tanto no tecido tumoral como na mucosa não neoplásica adjacente. Em vinte e três pacientes o DNA do HPV foi encontrado apenas no tumor, enquanto que em quatorze, só foram encontrados nos tecidos normais coletados próximos ao tumor de cólon e reto. Em setenta e cinco por cento dos casos positivos foram identificados os HPV tipo 16 ou 18 por PCR com primers E6 específicos. Os achados positivos obtidos por PCR foram confirmados por seqüenciamento viral. CONCLUSÃO: O HPV está presente no cólon e reto da maioria dos pacientes com carcinoma de cólon e reto estudados, sugerindo que este vírus pode estar relacionado à patogênese do câncer colorretal. Serão necessários mais estudos para determinar o papel do HPV na carcinogênese colorretal.

Avaliação dos efeitos do álcool e da cafeína em modelo de carcinogênese pancreática induzida por 7,12 dimetilbenzentraceno (DMBA) em camundongos

Introdução: Modelos experimentais de indução da carcinogênese pancreática são necessários para melhor compreensão da biologia tumoral e para estudar os efeitos de agentes promotores ou protetores. Objetivos: Avaliar os efeitos do álcool e da cafeína na carcinogênese pancreática induzida pelo 7,12- dimetilbenzantraceno (DMBA), aplicando a classificação sistematizada de neoplasias intra-epitelias pancreáticas (PanIN) de Hruban e cols. (2001)(1) em camundongos. Métodos: Cento e vinte camundongos mus musculus, machos, adultos foram divididos em quatro grupos. Em todos os animais foi induzida a carcinogênese pancreática pela implantação de 1mg de DMBA no pâncreas dos animais. Os animais recebiam ou água ou cafeína ou álcool ou álcool+cafeína de acordo com seu grupo. Para a análise histológica do pâncreas, adotou-se a classificação sistematizada das lesões precursoras (PanIN). Resultados: No grupo água + DMBA, 16,6% dos animais desenvolveram adenocarcinoma ductal pancreático (ADP) e 66,6% apresentaram neoplasias intra-epiteliais pancreáticas (PanIN). No grupo álcool + DMBA, 52,9% desenvolveram ADP (p<0,05) e 35,3% PanIN. No grupo cafeína + DMBA, 15% apresentaram ADP e 65% PanIN. No grupo álcool+cafeína + DMBA, 23,8% desenvolveram ADP e 71,4% PanIN. Conclusões: O modelo experimental de carcinogênese pancreática em camundongos utilizando o DMBA, é eficaz na indução de lesões precursoras e de adenocarcinoma pancreático. O álcool está associado ao aumento da freqüência de adenocarcinoma pancreático, enquanto que a cafeína não demonstrou este efeito.

Bioprospecção de extratos metanólicos de macroalgas marinhas do litoral do Rio Grande do Norte: avaliação das atividades anticoagulante, antioxidante e antiproliferativa

Seaweeds are organisms known to exhibit a variety of biomolecules with pharmacological properties. The coast of Rio Grande do Norte has over 100 species of seaweeds, most of them not yet explored for their pharmacological potential. Sugars and phenolic compounds are the most studied of these being assigned a range of biological properties, such as anticoagulant , antiinflammatory, antitumor and antioxidant activities. In this work, we obtained methanolic extracts from thirteen seaweeds of the coast of Rio Grande do Norte (Dictyota cervicornis; Dictiopterys delicatula; Dictyota menstruallis; D. mertensis; Sargassum filipendula; Spatoglossum schröederi; Acanthophora specifera; Botryocladia occidentalis; Caulerpa cupresoides; C. racemosa; C. prolifera; C. sertularioides e Codium isthmocladum). They were evaluated as anticoagulant and antioxidant drugs, as well as antiproliferative drugs against the tumor cell line HeLa. None of the methanolic extracts showed anticoagulant activity, but when they were evaluated as antioxidant drugs all of extracts showed antioxidant activity in all tests performed (total antioxidant capacity, sequestration of superoxide and hydroxyl radicals, ferric chelation and reductase activity), especially the algae D. mentrualis, D. cilliolata and C. prolifera, who had the greatest potential to donate electrons.In addition, the ability of iron ions chelation appears as the main antioxidant mechanism of the methanolic extracts of these seaweeds mainly for the extract of the C. racemosa seaweed, which reached almost 100% activity. In the MTT assay, all extracts showed inhibitory activity at different levels againts HeLa cells. Moreover, D. cilliolata (MEDC) and D. menstrualis (MEDM) extracts showed specific activity to this cell line, not inhibiting the viability of 3T3 normal cell line, so they were chosen for detailing the antiproliferative mechanism of action. Using flow cytometry, fluorescence microscopy and in vitro assays we demonstrated that MEDC and MEDM induced apoptosis in HeLa cells by activation of caspases 3 and 9 and yet, MEDC induces cell cycle arrest in S phase. Together, these results showed that the methanolic extracts of brown seaweed D. menstrualis and D. cilliolata may contain agents with potential use in combatting cells from human uterine adenocarcinoma. This study also points to the need for more in-depth research on phytochemical and biological context to enable the purification of biologically active products of these extracts

Avaliação in vitro da eficácia de produtos homeopáticos contendo momordica charantia através de bioensaios

Homeopathic medicines have been used for over two hundred years without the examination of their effects on in vivo and in vitro assays, due to the peculiarity of homeopathic preparations, the high dilution, which creates a challenge for the use of usual analytical techniques of quality control of medicine.Although there is scarcity of literature and variety of experiments, recently there have been some studies with few in vitro assays which have shown positive responses when evaluating the mechanism of action of homeopathic medicines which are able to act on a specific system.The present study aims to evaluate the efficacy of homeopathic products containing Momordica charantia through bioassays.Homeopathic products were tested by the MTT to assess cytotoxicity in RAW 264.7 (macrophage-like cells) and in tumor cells HeLa (human cervical adenocarcinoma cells), CHO K1 (Chinese hamster ovary cells), PANC-1 (human pancreas cancer cells) and PC-3 (human prostate cancer cells), dosage of inflammatory mediators NO, TNF-α and IL-6 released by RAW 264.7 cells, analysis of the death process and cell cycle changes of PC-3 by flow cytometry. The data demonstrate that homeopathic products of Momordica charantia did not show cytotoxicity to RAW 264.7, increased the production of inflammatory mediators by RAW 264.7 synergistically with LPS, showed cytotoxicity to PC-3 with change in its cell cycle inhibiting its proliferation, being the 30CH the most potent sample. Correlation studies were conducted in order to evaluate the possible in vitro applicable models to the quality control of homeopathic products with Momordica charantia. The data showed that the best applicable models in assessing the quality are the MTT to assess cytotoxicity in RAW 264.7 and PC-3 in 24 hours for Momordica charantia fruit products and dosage of NO production by RAW 264.7 with and without LPS

Surgical treatment of gynaecomastia in a Saanen goat

Background: Gynaecomastia in male goats is characterized by abnormal development of the mammary gland. Enlarged udder may be observed cranially to the scrotum, which can occasionally reach the size of the testicles. The udder may carry functional glands and impair the animal's reproductive performance and welfare. The case of a successful surgical treatment of gynaecomastia in a high reproductive performance Saanen buck-goat is reported in the present study.Material, Methods & Results: The animal was admitted presenting significant augmentation of the mammary glands, which was clinically diagnosed as gynaecomastia. The male goat owned optimal phenotypic characteristics for the Saanen breed, which had been producing high performance descendents. The mammary glands had been impairing the goat's locomotion and sexual performance. Manual milking resulted in great amount of milk secretion. The animal presented anorexia and impaired sexual performance. After clinical and laboratorial evaluation, the animal was submitted to radical mastectomy. An elliptic skin incision was performed around each mammary gland. Subcuticular blunt dissection was accomplished to isolate the mammarian tissue from the abdominal muscular layer and the spermatic chord. The excised mass was sampled for histological assessment. Subcuticular layer and skin closure was carried in a routine fashion. Hygienization of the surgical wound was performed with 2,5% PVP-I solution for ten days. Additionally, an association of penicillin G benzathine and streptomycin, and fluxinin meglumine were also given. The surgical procedure was successfully accomplished without any peroperative complication. The excised mass was sampled for anatomic/histological assessment. Macroscopically, the left mammary gland presented 22 cm in length, 12 cm wide and 26 cm in diameter. The right gland presented 16 cm in length, 7 cm wide and 13,5 cm in diameter. The microscopic assessment revealed hyperplasia of the glandular ducts. No abnormalities resembling malignant mammary neoplasms or degeneration were observed. At the end of the treatment, the animal was completely recovered. The animal convalesced satisfactorily and surgical wound healed completely within the first 10 days post-op. The goat was not culled and returned to normal reproductive activity. Within 12 months of follow-up, the animal was able to produce high milk yield performance progenies.Discussion: This case report presented relevant aspects of the surgical management of gynaecomastia, especially to veterinary practitioners dealing with milk goats. Gynaecomastia is not as common as other reproductive disorders in domestic animals. In opposition to the findings of the present study, other trials revealed that gynaecomastia usually does not affect fertility, libido, ejaculate parameters and sexual performance of goats. However, it is important to consider that neoplasic disorders such as mammary adenocarcinoma may be present, even though these are rare complications. Last but not least, the decision making on mastectomy in the present study was crucial in order to reestablish the animal's welfare and its functionality in the farms reproduction program.

Controle da neoplasia maligna do colo de útero: a resolutividade na atenção básica

A quantitative, descriptive, cross-sectional and retrospective study, using technical procedures of document consultation from secondary sources and health household survey with application form for face to face inter views, with the assent nº.039/2011 from the Ethics Committee of the Federal University of Rio Grande do Norte. The aim of this study was to analyze the cervix cancer control in the area47 of the Health Family Centre Nova Natal II. The cancer cervix is the second most common cancer among women worldwide. In Brazil screening for early detection and treatment of disease has been poorly done and follow-up to reduce mortality has not been executed. From a total of1170women belonging to area 47, who under went screening by the Pap test in the period from 2005 to 2010,was elected a sample of 38 women with positive cervical changes, over 18 years old. The calculation of frequency analysis of socio demographic and clinical and epidemiological selected variables with the results of cervical changes, using the X2 test and taking as significance level of p<0.05 was not statistically significant. The predominant age range was 25 to 64 years (68.9%), most no white women (60.5%), predominantly with primary education (57.9%), most married (68.4%) and housewives (68.4%) with early age of sexual activity (86.8%), the minority smokers (13.2%), with a sexual partner (36.8%). At the time of interview, 42.1% of the women voiced complaint of discharge, while only 2.6% reported bleeding. In relation to the occurrence of STDs (including HPV), 10.5% of women reported being a carrier. The use of oral contraceptives was 32.3% of women, from 2 to 4 years (44.4%). The result of the last screening test performed, showed prevalence of immature squamous metaplasia (55.3%), followed by intraepithelial low- grade lesion (including the cytopathologic HPV effect and cervical intra epithelial neoplasia grade I) (31.6%); intraepithelial high-grade lesion (including cervical intraepithelial neoplasia grade II and III) (7.9%), atypical squamous non neoplastic cells (5.3%). There was no squamous cell carcinoma and adenocarcinoma. Most women received information about the action that should be done after the last screening test result (55.3%), but how to perform follow, most women did not report having done so (55.3%). The follow-up group of women studied, with varying degrees of cervical abnormalities, should only be completed with the discharge by cure, established inconsecutive negative cytology, a goal that is not being achieved in the area 47 of the Health Family Centre of Nova Natal II

New palladium(II) complexes with pyrazole ligands Part II. Synthesis, spectral and thermal studies, and antitumor evaluation

This study describes the synthesis, IR, (1)H, and (13)C{(1)H} NMR spectroscopic as well the thermal characterization of the new palladium(II) pyrazolyl complexes [PdCl(2)(HmPz)(2)] 1, [PdBr(2)(HmPz)(2)] 2, [PdI(2)(HmPz)(2)] 3, [Pd(SCN)(2)(HmPz)(2)] 4 {HmPz = 4-methylpyrazole}. The residues of the thermal decomposition were identified as Pd(0) by X-ray powder diffraction. From the initial decomposition temperatures, the thermal stability of the complexes can be ordered in the sequence: 1 > 2 > 4 a parts per thousand 3. The cytotoxic activities of the complexes and the ligand were investigated against two murine cancer cell lines: mammary adenocarcinoma (LM3) and lung adenocarcinoma (LP07) and compared to cisplatin under the same experimental conditions.

Antitumor and antimycobacterial activities of cyclopalladated complexes: X-ray structure of [Pd(C-2,N-dmba)(Br)(tu)] (dmba = N,N-dimethylbenzylamine, tu = thiourea)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

3,5-Dimethyl-1-thiocarbamoylpyrazole and its Pd(II) complexes: Synthesis, spectral studies and antitumor activity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

New palladium(II) complexes with pyrazole ligands Part I. Synthesis, spectral and thermal studies, and antitumor evaluation

The pyrazole ligand 3,5-dimethyl-4-iodopyrazole (HdmIPz) has been used to obtain a series of palladium(II) complexes (1-4) of the type [PdX(2)(HdmIPz)(2)] {X = Cl(-) (1); Br(-) (2); I(-) (3); SCN(-) (4)}. All compounds have been isolated, purified, and characterized by means of elemental analysis, IR spectroscopy, (1)H and (13)C{(1)H}-NMR experiments, differential thermal analysis (DTA), and thermogravimetry (TG). The TG/DTA curves showed that the compounds released ligands in the temperature range 137-605 A degrees C, yielding metallic palladium as final residue. The complexes and the ligand together with cisplatin have been tested in vitro by MTT assay for their cytotoxicity against two murine cancer cell lines: mammary adenocarcinoma (LM3) and lung adenocarcinoma (LP07).