Pollen tube reorientation is a dynamic cellular event that is crucial for successful fertilization. We have shown previously that pollen tube orientation is regulated by cytosolic free calcium ([Ca 2 ؉ ] c ). In this paper, we studied the activity of a Ca 2 ؉ -dependent protein kinase during reorientation. The kinase activity was assayed in living cells by using confocal ratio imaging of BODIPY FL bisindolylmaleimide. We found that growing pollen tubes exhibited higher protein kinase activity in the apical region, whereas nongrowing cells showed uniform distribution. Modification of growth direction by diffusion of inhibitors/activators from a micropipette showed the spatial redistribution of kinase activity to predict the new growth orientation. Localized increases in [Ca 2 ؉ ] c induced by photolysis of caged Ca 2 ؉ that led to reorientation also increased kinase activity. Molecular and immunological assays suggest that this kinase may show some functional homology with protein kinase C. We suggest that the tip-localized gradient of kinase activity promotes Ca 2 ؉ -mediated exocytosis and may act to regulate Ca 2 ؉ channel activity. INTRODUCTIONSuccessful fertilization in the angiosperms depends on pollen tubes finding their way to the ovule. Pollen tubes frequently change their direction of growth until they finally reach the micropyle. Previously (Malhó et al., 1994Malhó and Trewavas, 1996), we have shown that the distribution of cytosolic free calcium ([Ca 2 ϩ ] c ) in the apical region and Ca 2 ϩ influx by asymmetric activity of Ca 2 ϩ channels play crucial roles in this process. However, the downstream processes involved in signal transduction are not known (Feijó et al., 1995;Trewavas and Malhó, 1997).Phosphorylation cascades are known to be a major part of signaling pathways in plant cells, particularly those involving Ca 2 ϩ (Trewavas and Malhó, 1997). However, methods for imaging protein kinase in living cells are limited. Olds et al. (1995) used the fluorescent dye NBD-phorbol acetate to visualize the activation of protein kinase C (PKC) in living cells. This dye interacts directly with the protein, and the authors showed that when the cells were incubated in a solution of low-dye concentration, they remained viable and performed their physiological functions; continued protein synthesis and turnover might prevent the inactivation of significant amounts of the protein kinase by interaction with the dye. However, NBD-phorbol acetate is a single-wavelength dye, which makes quantitation difficult because it was designed primarily to label PKC. Despite the importance of this enzyme in the regulation of animal cell metabolism, direct sequence equivalents in plant cells have yet to be identified. Nevertheless, there is evidence for lipid-activated kinases that might represent functional equivalents (Nanmori et al., 1994; AboEl-Saad and Wu, 1995;Sokolova et al., 1997;Subramaniam et al., 1997). The loading of fluorescently labeled peptides (syntide-2) recently has been used to map the distribution of a membe...

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A maioria foi efetuada a mulheres (62%), idade média 52 anos, 4 anos de escolaridade (33%) e para situações agudas (53%). Foram substituídas 31% das prescrições, sem relação com idade, sexo ou escolaridade, nem com o médico prescritor ou farmácia. Os medicamentos prescritos para situações crónicas foram menos substituídos (p < 0,001), assim como as prescrições de marca (p < 0,001). Os anti-infeciosos e anti-alérgicos foram os grupos com mais substituições (p = 0,009). Os utentes não se aperceberam da substituição em 72% dos casos. Nos casos de substituição, o utente pagou, em média, mais 79% que o prescrito e o Serviço Nacional de Saúde 5%. Discussão/Conclusão: Verificou-se substituição de 31% das prescrições, com mais custos para utente e Serviço Nacional de Saúde. Consideramos possível viés de seleção, informação e registo. Sendo agora obrigatória a prescrição por DCI, sugerimos a análise regular, a nível nacional, com base nas aplicações informáticas em uso, da prescrição e respetiva dispensa. Palavras-chave: Cuidados de Saúde Primários; Custos e Análise de Custo; Prescrições de Medicamentos; Portugal; Substituição de Medicamentos. AbStRACtIntroduction: In order to cut spending, compulsory INN prescription was suggested in Portugal during 2012. This instigated discussion among stakeholders in the matter. The authors studied prescription-dispensing dynamics in a real population. Objectives: To determine the percentage of swapped prescriptions; to assess factors associated with the swap; to analyse justifications for doing so; to quantify the cost difference for patients and the National Health Service. Material and Methods: Analytic study. Convenience sample consisting of all prescriptions from a Primary Health Care unit, from the 19th to the 23rd December 2011. Third day follow-up, using phone call interviews. Software: Excel and SPSS. Tests: Chi-square and Mann-Whitney, SL = 0.05. Results: Total of 255 prescriptions. Majority prescribed to women (62%), mean age of 52, four years of school education and for acute situations. A percentage of 31% of prescribed drugs were swapped. The swaps had no statistical relation with age, sex or literacy of the patient, nor with the prescriber or pharmacy. Swapping of prescribed drugs for chronic situations was lower (p < 0.001), as well as for original brand prescriptions (p < 0.001). Anti-infectious and anti-allergic were the most swapped groups (p = 0.009). Seventy-two percent of users were not aware of the swap. Regarding the swapped drugs, users paid on average 79% more than what was originally prescribed, and the National Health Service 5% more. Discussion/Conclusion: The authors found changes in 31% of the prescriptions, with higher costs for both users and National Health Service. Selection, information and registration bias were considered. With compulsory INN prescriptions, we suggest regular analysis of prescription-dispensing dynamics, based on the available national data.

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