Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 23
Filter
1.
Oecologia ; 185(2): 281-291, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28840340

ABSTRACT

Over the past 10 million years, tropical savanna environments have selected for small growth forms within woody plant lineages. The result has been the evolution of subshrubs (geoxyles), presumably as an adaptation to frequent fire. To evaluate the traits associated with the shift from tree to subshrub growth forms, we compared seed biomass, germination, survival, resprouting, biomass allocation, and photosynthesis between congeneric trees and subshrubs, and quantified phylogenetic conservatism. Despite large differences in adult morphology between trees and subshrub species, the differences are modest in seedlings, and most of the variation in traits was explained by genus, indicating considerable phylogenic conservatism. Regardless, tree seedlings invested more heavily in aboveground growth, compared to subshrubs, which is consistent with the adult strategy of savanna trees, which depend on a large resistant-fire stem. Subshrub seedlings also invest in greater non-structural carbohydrate reserves, likely as an adaptation to the high fire frequencies typical of tropical savannas. The modest differences as seedlings suggest that selective pressures during early development may not have contributed substantially to the evolution of the subshrub growth form and that the distinct allocation and life history must arise later in life. This is consistent with the interpretation that the subshrub growth form arose as a life-history strategy in which maturity is reached at a small stem size, allowing them to reproduce despite repeated fire-induced topkill. The convergent evolution of subshrubs within multiple tree lineages reaffirms the importance of fire in the origin and diversification of the flora of mesic savannas.


Subject(s)
Grassland , Life History Traits , Plant Physiological Phenomena , Tropical Climate , Adaptation, Physiological , Fires , Phenotype , Phylogeny , Plant Stems/physiology , Plants/classification , Plants/genetics , Seedlings/growth & development
2.
Andrologia ; 45(1): 18-25, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22571794

ABSTRACT

The aim of this study was to investigate the prevalence of hyperinsulinaemia in a group of normozoospermic donors and the influence of insulin levels on in vitro fertilisation (IVF) outcome. Fasting insulin and 2 h post-eating insulin levels were determined for a group of thirty-four sperm donors. They were divided into three groups according to their insulin profiles. The association between insulin levels and embryo quality was determined in a clinical study for the different groups. The prevalence of raised insulin in the donor group was 44% with a 95% confidence interval of 27.2% and 62.1%. Donors with normal insulin levels produced more good quality blastocysts in the IVF programme than those with abnormal insulin levels. These differences were not statistically significant (P=0.8638). Embryo quality in an IVF programme may be influenced by male insulin levels. The role of insulin in male fertility needs to be investigated.


Subject(s)
Hyperinsulinism/epidemiology , Tissue Donors , Adult , Blastocyst/physiology , Body Mass Index , Fasting , Fertility/physiology , Fertilization in Vitro , Humans , Insulin/blood , Insulin/physiology , Life Style , Male , Postprandial Period , Semen Analysis , South America/epidemiology , Surveys and Questionnaires , Treatment Outcome
3.
Parasitol Res ; 93(3): 230-4, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15138807

ABSTRACT

BALB/c and C57BL/6 mice were experimentally infected with Angiostrongylus costaricensis and the parasitic parameters and antibody response during the acute and chronic phases of infection were analyzed. Following administration of six third-stage larvae (L3), there was no significant difference in the mean worm recovery or mean larval output. Coinciding with the maturation of worms in infected animals and with the egg output in mesenteric arteries, a strong increase in the humoral immune response was observed in both mouse strains. This response was characterized by a hypergammaglobulinemia, with a predominance of IgA and IgG1 during the acute phase of infection, and IgG1 and total IgE during the patent and post-patent periods. Significantly higher levels of IgM, IgG and IgG1 were found in BALB/c mice compared with C57BL/6 mice. On the other hand, a significantly higher concentration of IgA was detected at 6 and 7 weeks post-infection in C57BL/6 mice compared with BALB/c mice. Specific IgE could not be detected in any of the mouse strains. Our results suggest that immunoglobulins, mainly IgG1, contribute to the outcome of a primary A. costaricensis infection with respect to the period of patency and to mortality during the chronic phase.


Subject(s)
Angiostrongylus , Strongylida Infections/immunology , Strongylida Infections/parasitology , Angiostrongylus/immunology , Angiostrongylus/isolation & purification , Animals , Antibodies, Helminth/blood , Aorta/parasitology , Disease Models, Animal , Feces/parasitology , Heart/parasitology , Immunoglobulin A/blood , Immunoglobulin E/blood , Immunoglobulin G/blood , Immunoglobulin M/blood , Liver/parasitology , Mesenteric Arteries/parasitology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Survival Analysis , Time Factors
4.
J Parasitol ; 85(6): 1170-1, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10647052

ABSTRACT

Several density gradients were tested for the isolation of parasitic nematode, Angiostrongylus costaricensis, first-stage larvae from rodent feces. With a 45/72% Percoll gradient, 83-99% (89.56+/-6.57%) of the larvae were recovered in a clean preparation.


Subject(s)
Angiostrongylus/isolation & purification , Feces/parasitology , Rodent Diseases/parasitology , Strongylida Infections/veterinary , Animals , Centrifugation, Density Gradient , Colloids , Larva , Mice , Mice, Inbred C3H , Povidone , Silicon Dioxide , Strongylida Infections/parasitology
5.
s.l; s.n; 1935. 5 p.
Non-conventional in German | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1232965

Subject(s)
Leprosy
6.
s.l; s.n; 1935. 14 p.
Non-conventional in Spanish | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1233572

Subject(s)
Leprosy
7.
s.l; s.n; 1934. 6 p.
Non-conventional in Portuguese | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1237737
8.
s.l; s.n; 1934. 9 p.
Non-conventional in Spanish | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1233354

Subject(s)
Leprosy
9.
Int. j. lepr ; 1(2): 149-158, Apr. 1933. ilus
Article in English | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1227220

ABSTRACT

The leprosy bacillus, like other acid-fast bacilli, produces in its evolutionary cycle great numbers of granular forms which are found both within the bacilli and as free-lying bodies. These granules constitute an essential phase in its evolution. Among the free-lying forms are those of all sizes down to the limits of visibility, so that it is probable that still smaller, perhaps invisible and filterable forms exist, which may be of special though as yet unknown importance in the pathology and epidemiology of the disease. The supposition is feasible that many of these granular forms are phenomena of degeneration and disintegration, which are determined in part by the defensive substances of the organism and in part by the action of our medicinal products, and especially by the chaulmoogra oil; therefore, their presence can be considered a favorable sign. Howevwe, a careful study of the granular forms suggests that they should not be considered solely as degenerative forms. Evidence is given that in other cases they seem to be especially resistant or young forms, essential for the preservation and perhaps propagation of the microorganism of leprosy. Obviously, the importance of these forms for scientific study and practical work in leprosy cannot be overestimated...


Subject(s)
Leprosy , Leprosy/immunology , Leprosy/microbiology , Leprosy/transmission , Mycobacterium leprae/immunology , Mycobacterium leprae/metabolism , Mycobacterium leprae/pathogenicity
10.
s.l; s.n; 1933. 5 p.
Non-conventional in Spanish | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1233732

Subject(s)
Leprosy
11.
Würzburg; s.n; s.ed; 1932. 9p
Non-conventional in German | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1241537

Subject(s)
Chaulmoogra , Leprosy
12.
s.l; s.n; 1932. 9 p.
Non-conventional in English | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1232671

Subject(s)
Leprosy
13.
s.l; s.n; 1932. 4 p.
Non-conventional in Portuguese | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1232967

Subject(s)
Leprosy
14.
São Paulo; s.n; 1931. 9 p.
Non-conventional in Portuguese | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1239413
15.
s.l; s.n; 1930. 9 p. ilus.
Non-conventional in Spanish | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1238098

Subject(s)
Leprosy/diagnosis
16.
s.l; s.n; 1930. 3 p.
Non-conventional in Portuguese | LILACS-Express | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1235682
17.
s.l; s.n; 1929. 7 p.
Non-conventional in French | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1232483

Subject(s)
Leprosy
18.
s.l; s.n; 1927. 1 p.
Non-conventional in German | LILACS-Express | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1235698
19.
s.l; s.n; 1926. 2 p.
Non-conventional in German | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1231578

Subject(s)
Leprosy
20.
s.l; s.n; 1926. 2 p.
Non-conventional in Spanish | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1233304

Subject(s)
Leprosy
SELECTION OF CITATIONS
SEARCH DETAIL