Resumo em Inglês:

Integrins encompass a family of transmembrane heterodimeric proteins of adhesion that maintain cells attached to other cells and to the extracellular matrix (ECM). Integrins work as bi-directional mechanotransducers, conveying mechanical signal from outside to inside the cell through a cascade of phosphorylation signals. On the other hand, the signal from inside to outside controls the strength and affinity of integrin adhesion. As proteins of focal contact, integrins are involved in diverse cell functions, such as cell activation, migration, growth, and survival. In the development of neoplastic disease and metastatic tumor, integrins can influence cancer invasiveness and progression, as well as mediate the formation of new blood vessels (angiogenesis). Diverse snake venom toxins have the ability to interact with multiple integrins, what results in inhibition of cell attachment, inhibition of angiogenesis, and induction of apoptotic death of tumor and vascular endothelial cells. The aim of this review is to present data about snake venom toxins that bind to integrins and evoke antiangiogenesis and antitumoral effects.

Resumo em Inglês:

The epidemiological data on snakebites in the state of Paraíba, Brazil, is scarce. This accounts for the difficulties in helping the victims. Hence, to obtain the clinical and epidemic profile of the snakebite accidents in Paraíba, we studied the number of cases recorded in this state between January 1995 and December 2000. The data was collected from these sources: Center for Toxicological Assistance (Centro de Assistência Toxicológica - CEATOX) and State Secretariat of Health (Secretaria Estadual de Saude), João Pessoa; 3rd Regional Health Center (3º Núcleo Regional de Saúde - NRS) and the Division of Epidemiological Vigilance of the Municipal Secretariat of Health (Divisão de Vigilância Epidemiológica da Secretaria Municipal de Saúde - DVE/SMS), Campina Grande. The annual distribution of the snakebite incidence showed an irregularity and an increase in March, May and August; followed by a large reduction in November and December. It was also observed that snakebites occurred more frequently in the rural area, mainly among the male laborers between 10-49 years. In most cases, the bite occurred on the leg or foot. The interval between the snakebite and the medical assistance was less than six hours. The most common symptoms were pain, edema, erythema, and bleeding. The low lethality index and the high frequency of healing, without sequels, suggest that the treatment with serum neutralized the poison, indicating the efficacy of this treatment against snakebites by the specific species found in this region.

Resumo em Inglês:

Enterococcus faecalis is considered a pathogen responsible for hospital infections and, due to its frequent multi-resistant profile, has caused preoccupations among many medical authorities. The objective of this study was to determine the antimicrobial susceptibility of 74 strains isolated from blood cultures and purulent secretions to vancomycin and ciprofloxacin through the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) by using the Microdilution test. The results showed a greater efficacy of vancomycin compared to ciprofloxacin (98.6% of the strains were inhibited by vancomycin at lower concentrations: 0.06 - 1 µg/ml). However, in the MBC analysis 73% of the strains showed a MBC of vancomycin only at high concentrations (equal to or higher than 64 µg/ml). For ciprofloxacin, the strains showed a broad sensitivity with MICs and MBCs distributed along all the MIC classes. Results also revealed a probability that some strains are tolerant to vancomycin, which indicates the need of other tests to confirm this characteristic.

Resumo em Inglês:

The aim of this study was to evaluate the effect of snake venom derived fibrin glue on the strength oftendon healing in dogs. The deep digital flexor tendon of the 5th digit of 24 thoracic limbs was partially sectioned for adhesive application. On the 7th, 15th, and 30th postoperative day tendons segments were removed for the clinical and biomechanical study. Results indicated that 62.5% of the tendons showed stump retraction and 20.8% moderate to excessive adherence, which affected gliding. The biomechanical evaluation showed that, over time, tendon healing gained progressive resistance for maximum traction and permanent deformations with satisfactory results on the 15th day for rigidity and resilience compared to the other two studied periods. Snake venom derived fibrin glue promotes healing in dog flexor tendon.

Resumo em Inglês:

Snakebite is an important medical emergency. Anti-snake venom along with supportive care is the only specific treatment. However, many people put their faith in non-registered medical practitioners. Where medical aid is available, lack of trained health personnel jeopardizes the situation. This retrospective study, the first of its kind, was aimed at studying the pre-hospital treatment as well as the behavior of patients bitten by snakes and referred to the Postgraduate Institute of Medical Education and Research, Chandigarh, India. A total of 88 cases that occurred between January 1997 and December 2001 were studied. Seventy patients received treatment prior to admission (the majority was treated by non-registered medical practitioners, registered medical practitioners, and MBBS doctors). The various treatment modalities used were: anti-snake venom (ASV), tourniquet, incision and drainage (I&D), tetanus toxoid, injections, and tablets. Non-registered medical practitioners still preferred tourniquet and I&D. The patients who were referred within 24 hours stayed less time in the hospital and spent less money on the treatment compared to those who were referred after 24 hours. Non-registered medical practitioners and inadequately trained health staff are often the first contact of snakebite victims. Their traditional and unscientific methods of treatment lead to unnecessary morbidity and increased treatment cost. It is therefore necessary to train these people adequately so that proper treatment can be instituted at the earliest.

Resumo em Inglês:

Large scale mass rearing of natural enemies has been a mean of improving biological control in the sugarcane intensive agriculture. Among them, Cotesia flavipes, a gregarious koinobiont endoparasitoid, was imported by Brasil to control caterpillars of the sugarcane borer Diatraea saccharalis. The C. flavipes larval development depends on its association with polydnavirus, which blocks the host defense reaction. To verify if the oviposition sequence (1st, 2nd or 3rd) and the female condition (mated or virgin) interfere in the number of C. flavipes descendents, 4th instar caterpillars of D. saccharalis were parasitized. Analysis of the data showed that: a) there is an inverse correlation between the parasitism efficiency and the host reaction (encapsulation); b) the number of caterpillars parasitized by virgin females that released parasitoid larvae in the period from 12 to 15 days was higher than that of caterpillars parasitized by mated females; c) a slight difference between mated and virgin females in relation to the parasitim success was observed; and d) the number of encapsulated parasitoid larvae was higher than that of eggs, suggesting that eggs have a better capacity to overcome the host reaction. In this study, the viability of C. flavipes eggs and larvae in the non-specific host D. saccharalis could be correlated with the oviposition sequence and the female condition.

Resumo em Inglês:

ELISA was used to evaluate, follow, and compare the humoral immune response of Swiss mice during hyperimmunization with natural and Cobalt 60-irradiated (60Co) Crotalus durissus terrificus venom. Potency and neutralization were evaluated by in vitro challenges. After hyperimmunization, immunity was observed by "in vivo" challenge and the side effects were assessed. The animals immunization with one LD50 of the venom was on days one, 15, 21, 30, and 45, when blood samples were collected; the challenges occurred on the 60th day. Results showed that ELISA was efficient in evaluating, following, and comparing mouse immune response during hyperimmunization. Serum titers produced with natural venom were similar to those produced with irradiated venom. Immunogenic capacity was maintained after 60Co irradiation. Serum produced from Crotalus durissus terrificus irradiated venom showed higher potency and neutralization capacity than that from natural venom. All antibodies were able to neutralize five LD50 from these venoms. Clinical alterations were minimum during hyperimmunization with irradiated venom.

Resumo em Inglês:

A peptide toxin was isolated from the venom of Palamneus gravimanus, the Indian black scorpion, to block human Kv1.1 channels expressed in Xenopus laevis oocytes. A 4.5 kD peptide (toxin), as confirmed by SDS-PAGE, was purified to homogeneity by ion exchange chromatography using CM-Sephadex C-25 followed by Sephadex G-50 gel filtration. Palamneus gravimanus toxin (PGT) selectively blocks the human cloned voltage-gated potassium channel hKv1.1 in a two-electrode voltage-clamp (TEVC) technique. The results obtained indicate that the toxin blocks the hKv1.1 channel at a nanomolar concentration range (Ki value of 10 nM) of the peptide to the external side of the cell. The blockage seems to be voltage-dependent. Comparative structure of PGT (a 4.5 kD peptide) with BTK-2 suggests a close relationship; therefore this toxin can be employed to investigate the hKv1.1 channel structure.

Resumo em Inglês:

Alternative sources of anti-ophidic serum are being investigated due to the secondary effects associated with types I and II hypersensitivity reactions. In the present study we raised and evaluated the protective effect of an ovine antibothropic serum in a Swiss mice envenoming model. Ovine antiserum was obtained by immunization with seven increasing doses of bothropic venom associated with adjuvants. The neutralizing ability was tested by the lethal activity (2 LD50) neutralization and serum and splenic venom levels after antivenom administration to experimentally envenomed mice. The antiserum effect on local edema was also tested by injection of venom/antivenom mixtures into the mice footpads. Ovine antiserum neutralized lethal activity and also significantly decreased serum and splenic venom levels. However, this antiserum was not able to mediate any protective effect on edema triggered by bothropic venom.

Resumo em Inglês:

Gas chromatographic procedure with mass spectrometric detection was applied to quantitatively determine the enzymatic specificity and activity of vipoxin (a neurotoxin from the Vipera ammodytes meridionalis venom) as well as the influence of Ca2+, Mg2+ and Sr2+ on these properties.

Resumo em Inglês:

Visceral leishmaniasis is a zoonotic disease caused by parasites of the Leishmania genus. Dog is the major source of infection to man, especially in urban areas. The authors report a case of visceral leishmaniasis in a pit bull female dog from Bocaina, São Paulo, Brazil. The animal presented clinical signs compatible with leishmaniasis, including skin lesions in the body and partial damage of the external ears. The indirect fluorescent antibody test (IFAT) demonstrated a titer of 1280, and promastigote forms of Leishmania sp were isolated by the culture of bone marrow puncture. Cytological analysis of the lymph node and smear of the bone marrow puncture revealed macrophages containing amastigote forms of Leishmania sp in their inner region. The test of Polymerase Chain Reaction (PCR) utilized the primers LINR4 and LIN19, which amplify 720 base pairs, specific for Leishmania sp. The authors discuss the importance of techniques for a quick and precise diagnosis to this serious zoonosis with great impact in animal and public health.

Resumo em Inglês:

Haplometroides buccicola (Trematoda, Digenea, Plagiorchiidae) was reported in the mouth and oesophagus of Phalotris lativittatus (Serpentes, Colubridae) from Botucatu, São Paulo State, Brazil. This is the first report on the occurrence of H. buccicola parasitizing P. lativittatus. The Haplometroides genus was also discussed and the most important morphological characters for the identification of the species H. buccicola and H. odhneri are presented.