Spatial pattern and neighbour effects on Helianthemum squamatum seedlings in a Mediterranean gypsum community

Question: Do, in a semi-arid gypsum environment, neighbours condition the spatial patterns of emergence, survival and height of Helianthemum squamatum seedlings ? Location: Vicinity of Chinchón, province of Madrid, Spain (40°11'N, 3° 35'W, 550 m a.s.l.) Methods: We evaluated the effects of neighbours on the survival and growth of naturally emerging Helianthemum seedlings in a semi-arid area during a two-year period. We followed a two-fold approach based on the use of neighbour models for seedling survival and growth and spatial point pattern analyses for seedling emergence, taking into account the germination date. Results: Seedlings appeared clumped in the vicinity of mature Helianthemum individuals. The neighbour models fitted showed that interactions with neighbours were extremely important for the survival and growth of Helianthemum seedlings. These models also suggest that the effects of neighbours on these variables vary with changes in spatial scale and in the abiotic conditions. Some species exerted negative or positive effects on Helianthemum seedlings only at certain spatial scales, and others exerted negative or positive effects at earlier stages of seedling development, but none later and vice versa. Conclusions: We suggest that the observed patterns are mainly influenced by small-scale modifications in soil conditions and microclimate created by neighbours, which change in time and space

The ion transporter superfamily

AbstractWe define a novel superfamily of secondary carriers specific for cationic and anionic compounds, which we have termed the ion transporter (IT) superfamily. Twelve recognized and functionally defined families constitute this superfamily. We provide statistical sequence analyses demonstrating that these families were in fact derived from a common ancestor. Further, we characterize the 12 families in terms of (1) the known substrates transported, (2) the modes of transport and energy coupling mechanisms used, (3) the family sizes (in numbers of sequenced protein members in the current NCBI database), (4) the organismal distributions of the members of each family, (5) the size ranges of the constituent proteins, (6) the predicted topologies of these proteins, and (7) the occurrence of non-homologous auxiliary proteins that may either facilitate or be required for transport. No member of the superfamily is known to function in a capacity other than transport. Proteins in several of the constituent families are shown to have arisen by tandem intragenic duplication events, but topological variation has resulted from a variety of dissimilar genetic fusion, splicing and insertional events. The evolutionary relationships between the members of each family are defined, leading to predictions of functionally relevant orthologous relationships. Some but not all of the families include functionally dissimilar paralogues that arose by early extragenic duplication events

Autodoação e autotransfusão de sangue pré-doado em cirurgia cardíaca com circulação extracorpórea Autodonation and autotransfusion of pre-donated blood in cardiac surgery with cardiopulmonary bypass

Estudo prospectivo, entre agosto de 1987 e setembro de 1988, em 80 pacientes adultos submetidos a cirurgia cardíaca eletiva com circulação extracorpórea (CEC) aferindo a eficácia da autodoação (AD) e autotransfusão (AT) em reduzir o uso de sangue e hemoderivados homólogos (SDH). O Grupo Controle (GC) não foi submetido a AD (n =38). Coleta pré-operatória de sangue foi realizada em 42 pacientes, constituindo o Grupo Autodoação (GAD), iniciando-se de um a sete dias pré-operatórios (GAD I n=29) e entre oito a 14 dias pré-operatórios (GAD II n = 13). Os Grupos GC e GAD foram bastante semelhantes nos seus parâmetros pré, intra e pós-operatórios. Os resultados demonstraram que a utilização de hemoderivados foi similar, nos diversos grupos. Contudo, o número de pacientes expostos a SDH: GC 27 (71%) x GAS 10 (23,8%), p < (0,001); o volume médio de SHD (GC 1241 ml x GAD 412 ml, p <0,003) e o número médio de unidades homólogas utilizadas (GC 6,31 x GAD 1,95, p < 0,001) demonstraram que AD e AT foram eficazes em reuzir em 64% o volume médio de SDH, diminuindo a exposição a unidades homólogas e minimizando o número de pacientes expostos. O GAD II obteve os melhores índices, mas não atinge significado estatístico quando comparado ao GAD I, talvez devido ao pequeno número de pacientes. Acreditamos que AD e AT devem ser incentivadas em cirurgia cardíaca eletiva.<br>This is a prospective study performed from August 1987 to September 1988, including 80 adult patients who underwent elective cardiac surgery with cardiopulmonary bypass, for the purpose of assessing the efficacy of autodonation (AD) and autotransfusion (AT) in reducing the use of homologous blood and blood products (SDH). The Control Group (GC) did not undergo autodonation (n=38). Pre-operative collection of flood was performed in 42 patients, forming the autodonation Group (GAD), beginning from I to 7 days pre-operatively (GAD I; n=29), and from 8 to 14 days pre-operatively (GAD II; n = 13). Groups GC and GAD had very similiar "pre", "intra" and "post-operative" parameters. The results showed that the use of blood and blood products was similar in the various groups. Nevertheless, the number of patients exposed to SDH (GC 27 (71%) x GAD 10 (23.8%) - p < 0.001), the mean volume of SDH (GC 1241 x GAD 412 ml - p < 0.003) and the mean number of Homologous Units used (GC 6.31 x GAD 1.95 - p < 0.001) demonstrated that AD and AT were efficacious, reducing in 64% the mean volume of SDH, diminishing the exposure to Homologous Units and minimizing the number of patients exposed. The GAD II attained the best indexes, not reaching, however, statistical significance when compared to GAD I, possibility due to the small number of patients. We believe that AT & AD should de encouraged in elective cardiac surgery