Effects of a PPARG gene variant on obesity characteristics in Brazil

The contribution of genetic factors to the development of obesity has been widely recognized, but the identity of the genes involved has not yet been fully clarified. Variation in genes involved in adipocyte differentiation and energy metabolism is expected to have a role in the etiology of obesity. We assessed the potential association of a polymorphism in one candidate gene, peroxisome proliferator-activated receptor-gamma (PPARGg), involved in these pathways and obesity-related phenotypes in 335 Brazilians of European descent. All individuals included in the sample were adults. Pregnant women, as well as those individuals with secondary hyperlipidemia due to renal, liver or thyroid disease, and diabetes, were not invited to participate in the study; all other individuals were included. The gene variant PPARG Pro12Ala was studied by a PCR-based method and the association between this genetic polymorphism and obesity-related phenotypes was evaluated by analysis of covariance. Variant allele frequency was PPARG Ala12 = 0.09 which is in the same range as described for European and European-derived populations. No statistically significant differences were observed for mean total cholesterol, LDL cholesterol, HDL cholesterol, or triglyceride levels among PPARG genotypes in either gender. In the male sample, an association between the PPARG Pro12Ala variant and body mass index was detected, with male carriers of the Ala variant presenting a higher mean body mass index than wild-type homozygotes (28.3 vs 26.2 kg/m², P = 0.037). No effect of this polymorphism was detected in women. This finding suggests that the PPARG gene has a gender-specific effect and contributes to the susceptibility to obesity in this population.

Possible in vivo mechanisms involved in photodynamic therapy using tetrapyrrolic macrocycles

Photodynamic therapy (PDT) mediated by oxidative stress causes direct tumor cell damage as well as microvascular injury. To improve this treatment new photosensitizers are being synthesized and tested. We evaluated the effects of PDT with 5,10,15,20-tetrakis(4-methoxyphenyl)-porphyrin (TMPP) and its zinc complex (ZnTMPP) on tumor levels of malondialdehyde (MDA), reduced glutathione (GSH) and cytokines, and on the activity of caspase-3 and metalloproteases (MMP-2 and -9) and attempted to correlate them with the histological alterations of tumors in 3-month-old male Wistar rats, 180 ± 20 g, bearing Walker 256 carcinosarcoma. Rats were randomly divided into five groups: group 1, ZnTMPP+irradiation (IR) 10 mg/kg body weight; group 2, TMPP+IR 10 mg/kg body weight; group 3, 5-aminolevulinic acid (5-ALA+IR) 250 mg/kg body weight; group 4, control, no treatment; group 5, only IR. The tumors were irradiated for 15 min with red light (100 J/cm², 10 kHz, 685 nm) 24 h after drug administration. Tumor tissue levels of MDA (1.1 ± 0.7 in ZnTMPP vs 0.1 ± 0.04 nmol/mg protein in control) and TNF-α (43.5 ± 31.2 in ZnTMPP vs 17.3 ± 1.2 pg/mg protein in control) were significantly higher in treated tumors than in controls. Higher caspase-3 activity (1.9 ± 0.9 in TMPP vs 1.1 ± 0.6 OD/mg protein in control) as well as the activation of MMP-2 (P < 0.05) were also observed in tumors. These parameters were correlated (Spearman correlation, P < 0.05) with the histological alterations. These results suggest that PDT activates the innate immune system and that the effects of PDT with TMPP and ZnTMPP are mediated by reactive oxygen species, which induce cell membrane damage and apoptosis.

Aspectos morfológicos da semente e do desenvolvimento da planta jovem de Amburana cearensis (Arr. Cam.) A.C. Smith - Cumaru - Leguminosae Papilionoideae

Os objetivos deste trabalho foram descrever e ilustrar os aspectos morfológicos da semente e do desenvolvimento da planta jovem de Amburana cearensis. Os frutos foram coletados de cinco matrizes distantes no mínimo 100m, levando-se em consideração o aspecto fitossanitário e a intensidade de frutificação. O endocarpo permanece aderido à semente formando uma ala, mesmo após a deiscência; o hilo apresenta fenda longitudinal típica da sub-família; a germinação é do tipo semi-hipógea fanerocotiledonar e, com o desenvolvimento observou-se a presença de uma tuberosidade na raiz primária. Os caracteres descritos e ilustrados mostraram-se bastante homogêneos entre as cinco matrizes, podendo ser empregados para identificação da referida espécie, tanto em trabalhos de laboratório e de produção de mudas quanto em estudos ecológicos.

Morfo-anatomia do fruto e semente de amarelinho (Tecoma stans (L.) Kunth - Bignoniaceae)

O conhecimento restrito sobre a biologia da espécie Tecoma stans (L.) Kunth (Bignoniaceae), conhecida por amarelinho e a importância que a mesma vem adquirindo, principalmente, por sua característica invasora, motivaram o presente trabalho. Aspectos anatômicos do fruto e semente podem ser usados em taxonomia, bem como em estudos relacionados à ecologia da espécie. O objetivo foi descrever e ilustrar a morfo-anatomia do fruto e das sementes de amarelinho. Frutos de diferentes plantas foram coletados, aleatoriamente, nos municípios de Jacarezinho e Maringá, Norte do Estado do Paraná. Foram confeccionadas lâminas permanentes e semipermanentes. A análise morfológica e anatômica permitiu as seguintes observações: fruto seco deiscente do tipo cápsula loculicida; ovário bicarpelar, bilocular com um septo mediano longitudinal e óvulos anátropos unitegumentados; linha de deiscência presente desde o início do desenvolvimento do fruto, quando a camada contínua de fibras é interrompida por uma faixa de células parenquimáticas; semente alada, exalbuminosa, com envoltório coriáceo que reveste o embrião. O embrião é reto, com eixo hipocótilo-radicular curto e plúmula inconspícua. A ala da semente é membranosa e hialina.