Rosy Iara Maciel de Azambuja Ribeiro

Concomitant consumption of marijuana, alcohol and tobacco in oral squamous cell carcinoma development and progression: Recent advances and challenges

Oral squamous cell carcinoma (OSCC) corresponds to 95% of all malignant tumours of the mouth. The association between alcohol and tobacco is the major risk factor for this disease, increasing the chances for the development of OSCC by 35-fold. The plant, Cannabis sativa is smoked as cigarettes or blunts and is commonly used in association with tobacco and alcohol. Any type of smoking habit exposes individuals to a wide range of carcinogens or pro-carcinogens, such as polycyclic aromatic hydrocarbons, as well as some ethanol derived substances such as acetaldehyde (AA), and all are genotoxic in the same way. In addition, ethanol acts in the oral mucosa as a solvent and therefore increases the cellular membrane permeability to carcinogens. Carcinogens found in tobacco are also concentrated in marijuana, but the latter also contains high levels of cannabinoids, bioactive compounds responsible for several effects such as euphoria and analgesia. However, Δ(9)-tetrahydrocannabinol (Δ(9)-THC), the major psychotropic cannabinoid found in plants, causes a reduction of cellular metabolism and induction of apoptosis, both of which are anti-neoplastic properties. Apart from limited epidemiologic and experimental data, the effects of concomitant chronic exposure to marijuana (or Δ(9)-THC), tobacco and alcohol in OSCC development and progression is poorly known. This paper reviews the most recent findings on the effects of marijuana over cellular proliferation, as well as in the risk for OSCC, with emphasis on its interaction with tobacco and ethanol consumption.

Paracoccidioidomycosis: a series of 66 patients with oral lesions from an endemic area

Paracoccidioidomycosis (PCM) is the most important systemic mycosis in Latin America. It has been regarded as a multifocal disease, with oral lesions as the prominent feature. To provide useful information concerning the diagnosis and management of the disease, this study describes demographic and clinical data from the medical records of a consecutive series of 66 Brazilian patients from an endemic area, evaluated in a referral centre for oral diagnosis. In this sample of patients, there was a predominance of middle‐aged male patients, who were primarily rural workers. Chronic multifocal disease was prevalent, with lesions also detected in the lungs, lymph nodes, skin or adrenal glands. Most of the cases presented with lesions at the gingival mucosa followed by the palate and lips; these conditions occurring in the oral cavity were frequently associated with pain. Importantly, most of the patients sought professional care for oral lesions. The diagnosis was obtained through exfoliative cytology and/or biopsy of the oral lesions. Medical treatment was effective, and there were no mortalities in the sample. The present findings not only confirm the importance of oral lesions in the diagnosis and management of PCM but also illustrate that questions still remain unclear, such as the possibility of direct inoculation of the fungus onto oral tissues.

Synthesis and evaluation of sesquiterpene lactone inhibitors of phospholipase A2 from Bothrops jararacussu

Several sesquiterpene lactone were synthesized and their inhibitive activities on phospholipase A(2) (PLA(2)) from Bothrops jararacussu venom were evaluated. Compounds Lac01 and Lac02 were efficient against PLA(2) edema-inducing, enzymatic and myotoxic activities and it reduces around 85% of myotoxicity and around 70% of edema-inducing activity. Lac05-Lac08 presented lower efficiency in inhibiting the biological activities studied and reduce the myotoxic and edema-inducing activities around only 15%. The enzymatic activity was significantly reduced. The values of inhibition constants (K(I)) for Lac01 and Lac02 were approximately 740 μM, and for compounds Lac05-Lac08 the inhibition constants were approximately 7.622-9.240 μM. The enzymatic kinetic studies show that the sesquiterpene lactones inhibit PLA(2) in a non-competitive manner. Some aspects of the structure-activity relationships (topologic, molecular and electronic parameters) were obtained using ab initio quantum calculations and analyzed by chemometric methods (HCA and PCA). The quantum chemistry calculations show that compounds with a higher capacity of inhibiting PLA(2) (Lac01-Lac04) present lower values of highest occupied molecular orbital (HOMO) energy and molecular volume (VOL) and bigger values of hydrophobicity (LogP). These results indicate some topologic aspects of the binding site of sesquiterpene lactone derivatives and PLA(2).

Evaluation of healing wound and genotoxicity potentials from extracts hydroalcoholic of Plantago major and Siparuna guianensis

Despite the large use of the Plantago major and Siparuna guianensis in traditional medicine, there are no studies demonstrating the effectiveness from extracts of these plants in the healing process by the present methodology. This study reported the effects and toxicity of the P. major and S. guianensis extracts in the wound healing compared with a commercial product used in Brazil by macroscopic and microscopic analysis. Following injury in cervical dorsal area of the mice, the extract from P. major and S. guianensis and ointment was applied after an injury in cervical dorsal area of the mice. Wound healing rates were calculated at 4, 9, 15 and 21 d after the wounding, and tissues were obtained on the ninth day for histological analysis. Moreover, mutagenic assay of extracts was performed. Mutagenicity studies carried out with plant extracts showed not mutagenic with or without metabolic activations. Reduction of the wound area occurred earlier in mice treated with P. major and control treatment. On the 15th day, the complete wound closure occurred in P. major-treated wounds. Throughout ointment and S. guianensis treatment it was not observed the wound closured. Microscopic analyses of the wound, on the ninth day, showed the more efficient formation of the neoepithelium and skin appendages in animals treated with S. guianensis and P. major, while ointment treatment presented no re-epithelialization and absent skin appendages in wound. Thus, P. major extract showed good effects on wound healing processes rendering it a promising candidate for the treatment of wounds what also justified its traditional usage in wound treatment.

Comparative histology in the liver and spleen of three species of freshwater teleost

Nos descrevemos e comparamos a histologia do figado e do baco de Geophagus brasiliensis (Perciformes), Hypostomus francisci (Siluriformes) e Hoplias aff. malabaricus (Characiformes), peixes neotropicais de agua doce. Em G. brasiliensis e H. aff. malabaricus os hepatocitos organizaram-se na forma tubular enquanto que em H. francisci eles apresentaram-se como cordoes celulares. Em todas as especies, os hepatocitos apresentaram glicogenio, mas em G. brasiliensis e H. aff. malabaricus, eles mostraram forte marcacao para hemossiderina no citoplasma. Em G. brasiliensis e H. aff. malabaricus, centros melanomacrofagicos (CMMs) foram associados a estruturas hepaticas e somente em G. brasiliensis foi observado pâncreas exocrino intrahepatico. O baco, em todas as especies, foi caracterizado pela polpa vermelha e branca sem limites entre as duas regioes, mas somente em H. francisci foi registrado uma organizacao nodular no parenquima esplenico. G. brasiliensiseH. aff. malabaricusapresentaram na polpa branca CMMs associados principalmente a elipsoides. Alem disso, nos observamos CMMs grandes no baco em relacao ao figado de G. brasiliensis e de H. aff. malabaricus. No figado, valores altos de fibras reticulares e colageno foram observado em G. brasiliensis. No baco, valores altos de fibras reticulares e colageno foram registrados em H. aff. malabaricuseH. francisci, respectivamente. Diferencas histologicas confirmam a hipotese que a distância filogenetica esta refletida no figado e no baco.

Could Na,K-ATPase play a role in potassium leakage from irradiated erythrocytes?

BACKGROUND In developing countries, the access to red blood cell (RBC) irradiators is restricted. Thus, it is a common practice in blood banks to stock irradiated RBC units until they expire. The aim of this work is to elucidate the involvement of Na,K-ATPase in potassium leakage from prophylactically irradiated RBCs. METHODS Whole blood was collected from healthy donors, and blood concentrates were irradiated with 25Gy of γ-radiation within 24h of collection. At days 3, 5, 7, 9, 11, 14 and 28 post-irradiation, fractions were removed and centrifuged and Na,K-ATPase activity from ghost membranes was determined. RESULTS The inhibition of Na,K-ATPase activity in RBCs reached 12.6% by day 7 of storage and up to 50% by day 14 of storage. The addition of vitamin C prevented the irradiation-induced loss of Na,K-ATPase activity. The irradiation of RBCs provoked an increase in potassium plasma levels and a decrease in sodium plasma levels. The incubation of RBCs with ouabain did not change the sodium or potassium levels in the plasma, and the addition of vitamin C only partially prevented a decrease in sodium levels caused by irradiation. CONCLUSION Because the inhibition of Na,K-ATPase by ouabain did not cause potassium accumulation in the plasma, we conclude that the irradiation-induced inhibition of the pump is not a key factor driving this effect.

Immunohistochemical Expression of Collagens in the Skin of Horses Treated with Leukocyte-Poor Platelet-Rich Plasma

This study evaluated the immunohistochemical expression of type I (COL I) and III (COL III) collagens during the healing process of skin treated with leukocyte-poor platelet-rich plasma (LP-PRP). Seven healthy gelding crossbred horses aged 16 to 17 years were used. Two rectangle-shaped wounds were created surgically in the right and left gluteal regions. Twelve hours after wound induction, 0.5 mL of the LP-PRP was administered in each edge of the wounds of one of the gluteal regions. The contralateral region was used as control (CG). Three samples were obtained: after wound induction (T0), 14 days (T1) of healing process, and after complete closure of the skin (T2). The normal skin (T0) showed strong staining for type III and I collagen in papillary and reticular dermis, respectively. In the scar of the treated group, COL III showed important (p < 0.05) increase in immunoreaction in T2 compared with T1. The administration of a single dose of LP-PRP 12 h after induction of wound in horses does not influence formation of collagens I and III. However, the intense labeling for COL III suggests that the tissue was still weak during the macroscopic closure of the wound, demonstrating that healing was not completely finished.

A Novel Phospholipase A2 (D49) from the Venom of the Crotalus oreganus abyssus (North American Grand Canyon Rattlesnake)

Currently, Crotalus viridis was divided into two species: Crotalus viridis and Crotalus oreganus. The current classification divides “the old” Crotalus viridis into two new and independent species: Crotalus viridis (subspecies: viridis and nuntius) and Crotalus oreganus (subspecies: abyssus, lutosus, concolor, oreganus, helleri, cerberus, and caliginis). The analysis of a product from cDNA (E6d), derived from the gland of a specie Crotalus viridis viridis, was found to produce an acid phospholipase A2. In this study we isolated and characterized a PLA2 (D49) from Crotalus oreganus abyssus venom. Our studies show that the PLA2 produced from the cDNA of Crotalus viridis viridis (named E6d) is exactly the same PLA2 primary sequence of amino acids isolated from the venom of Crotalus oreganus abyssus. Thus, the PLA2 from E6d cDNA is actually the same PLA2 presented in the venom of Crotalus oreganus abyssus and does not correspond to the venom from Crotalus viridis viridis. These facts highlight the importance of performing more studies on subspecies of Crotalus oreganus and Crotalus viridis, since the old classification may have led to mixed results or mistaken data.

Assessment of fish assemblage in an urban system, Itapecerica River, upper São Francisco River basin, Divinópolis, Minas Gerais, Brazil

Despite the economic and ecological importance of the Itapecerica River, there is no information about the local fish fauna. The aim of the present study was to provide a list of fish species in Itapecerica River, a tributary of the upper Sao Francisco River basin, inside an urban area. The specimens were collected quarterly from May 2010 to February 2012, using casting nets, trawl net and gillnets. We listed 29 species belonging to 21 genera of 14 families and 4 orders. Characiformes were represented by 16 species, Siluriformes by nine, Gymnotiformes and Perciformes by two each. Three alien species and five migratory fish were recorded. The low number of species found in this study in relation to Sao Francisco basin, could be reflecting the high level of degradation of waters in the Itapecerica River.

Anti-inflammatory effects of the butanolic fraction of Byrsonima verbascifolia leaves: Mechanisms involving inhibition of tumor necrosis factor alpha, prostaglandin E2 production and migration of polymorphonuclear leucocyte in vivo experimentation

The leaves of Byrsonima verbascifolia (Malpighiaceae) are traditionally used to treat various diseases including inflammatory conditions. The main goal of this study was to evaluate the in vivo anti-inflammatory activity of the polar constituents from the butanolic fraction of B. verbascifolia leaves (BvBF), as well as to investigate the mechanisms involved in the anti-inflammatory activity. The polar constituents were identified by liquid chromatography coupled to diode array detector and mass spectrometry (LC-DAD–MS) and matrix-assisted laser desorption/ionization – time-of-flight mass spectrometry (MALDI-TOF MS) to obtain a complete chemical profile of the fraction. Forty-five compounds were detected in the BvBF by LC-DAD–MS/MS, including condensed tannins, phenolic acids, flavonoids (flavones and flavonols) and other compounds. In addition, several condensed tannins were identified by MALDI-MS/MS, which are composed predominantly by procyanidin units (PCY) and up to six flavan-3-ol units. The BvBF exhibited significant antioxidant and anti-inflammatory activities. The BvBF inhibited paw edema and polymorphonuclear (PMN) leukocyte migration to the footpad and pleural cavity induced by carrageenan. Furthermore, a minor dose (12.50 mg/kg) of BvBF effectively decreased tumor necrosis factor alpha (TNF-α) and prostaglandin E2 (PGE2) levels in the footpad. These findings suggest that the mechanism of the anti-inflammatory action in the BvBF is linked to the inhibition of the production of inflammatory mediators such as TNF-α and PGE2 and the PMN cell migration.