Estresse osmótico na germinação de sementes de Petiveria alliacea L / Osmotic stress on seed germination of Petiveria alliacea L

RESUMOO trabalho teve como objetivo verificar os efeitos dos estresses hídrico e salino na germinação de sementes de Petiveria alliacea , bem como definir os limites máximos de tolerância da espécie a esses estresses. As sementes foram submetidas aos agentes osmóticos NaCl, CaCl2 e PEG nos potenciais à 0; -0,1; -0,2; -0,3; -0,4; -0,5; -0,6; -0,7; -0,8; -0,9 e -1,0 MPa sob temperatura constante de 25˚C e fotoperíodo de 12 horas, com avaliações diárias durante 30 dias. As variáveis analisadas foram porcentagem de germinação, índice de velocidade de germinação, tempo médio de germinação, índice de sincronização e frequência relativa da germinação. As sementes de P. alliacea sob estresse osmótico apresentam menor porcentagem e velocidade de germinação com a redução dos potencias osmóticos, principalmente com CaCl2. Em potenciais osmóticos mais negativos que -0,4; -0,5 e -0,7 MPa, respectivamente nos agentes CaCl2, NaCl, e PEG, não ocorre germinação. O padrão de distribuição da frequência relativa aumentou a polimodalidade, o tempo médio de germinação e o índice de sincronização da germinação com a redução dos potencias osmóticos.

ABSTRACTThe study aimed to investigate the effects of water and salt stress on seed germination of Petiveria alliacea, as well as to define the limits of tolerance of the species to these stresses. The seeds were subjected to osmotic agents NaCl, CaCl2 and PEG in the potential 0; -0.1; -0.2; -0.3; -0.4; -0.5; -0.6; -0.7; -0.8; -0.9 and -1.0 MPa at a constant temperature of 25˚C and a photoperiod of 12 hours, with daily assessments for 30 days. The variables studied were germination percentage, germination velocity index, middle fear germination, synchronization index and relative frequency of germination. The seeds of P. alliacea under osmotic stress had lower percentage and speed of germination with the reduction of the the osmotic potential, especially with CaCl2. At more negative osmotic potentials than -0.4; -0.5 and -0.7 MPa, respectively in the CaCl2, NaCl, and PEG agents, the germination does not occur. The distribution pattern of the relative frequency increased the several modalities, , the average time of germination and the germination index of synchronization with the reduction of osmotic potential.

Use of antivenoms for the treatment of envenomation by Elapidae snakes in Guinea, Sub-Saharan Africa

Background In Guinea Elapids are responsible for 20% of envenomations. The associated case fatality rate (CFR) ranged 15-27%, irrespective of treatment. Results We studied 77 neurotoxic envenomations divided in 3 groups: a set of patients that received only traditional or symptomatic treatments, and two other groups that received either 2 or 4 initial vials of Antivipmyn® Africa renewed as necessary. CFR was 27.3%, 15.4% and 17.6%, respectively. Although antivenom treatment was likely to reduce CFR, it didn’t seem to have an obvious clinical benefit for the patients, suggesting a low treatment efficacy. Mean delay to treatment or clinical stages were not significantly different between the patients who recovered and the patients who died, or between groups. Interpretation of these results is complicated by the lack of systematic studies under comparable conditions. Of particular importance is the absence of assisted ventilation, available to patients in all the other clinical studies of neurotoxic envenomation. Conclusion The apparent lack of clinical benefit may have several causes. The hypothesis of a limited therapeutic window, i.e. an insufficient formation of antigen-antibody complexes once toxins are bound to their targets and/or distributed beyond the reach of antivenom, should be explored. .

Lagoftalmos bilateral en paciente con lepra lepromatosa. Caso clínico / Bilateral lagophthalmos inlepromatous leprosy. Case report

CASE REPORT: A case of bilateral facial palsy with paralytic ectropion, lagophthalmos and corneal damage secondary to corneal exposure in a long-standing patient with lepromatous leprosy is presented. Correction of paralytic ectropion was performed by medial cantoplasty, tarsal strip and Medpor lower eyelid spacer implantation. Lagophthalmos was corrected by gold weight implant in the upper tarsus. DISCUSSION: Ocular findings in leprosy appear in 72 per cent of patients. Facial nerve palsy occurs in 3-19.8 per cent, being bilateral in 5 per cent. In long standing cases with corneal complications secondary to exposure, surgical treatment is required.