27 research outputs found
HDL: the yin-yang of cardiovascular disease
Estudos epidemiológicos mostram relação inversa entre nÃveis plasmáticos de HDL-colesterol (HDL-C) e incidência de doença cardiovascular (DCV). O papel antiaterogênico da HDL é atribuÃdo à s suas atividades anti-inflamatória, antitrombótica e antioxidante, além de sua participação no transporte reverso de colesterol (TRC), processo pelo qual a HDL remove colesterol dos tecidos periféricos, incluindo macrófagos da Ãntima arterial, e o transporta para o fÃgado para ser excretado pela bile. Com base nesses fatos, o HDL-C tornou-se alvo atrativo para a prevenção da DCV. No entanto, o fracasso do torcetrapib, droga que aumenta substancialmente os nÃveis de HDL-C, em prevenir DCV, além do conhecimento gerado por estudos de modelos animais e doenças monogênicas que afetam a concentração de HDL-C, tem suscitado questionamentos sobre o papel antiaterogênico da HDL. Esta revisão tem como objetivo abordar aspectos atuais do conhecimento da HDL, baseando-se nessas recentes controvérsias.Epidemiological studies demonstrate an inverse correlation between plasma HDL-cholesterol (HDL-C) concentration and incidence of cardiovascular disease (CVD). The antiatherogenic role of HDL has been attributed to its anti-inflammatory, antithrombotic and antioxidant properties, besides its participation in the reverse cholesterol transport (RCT), whereby cholesterol from peripheral tissues (including macrophages of the arterial intima) is delivered to the liver for excretion in bile. Due to these actions, HDL-C has evolved as an attractive target for prevention of CVD. However, the failure of torcetrapib, drug that substantially increases HDL-C levels, in preventing CVD and data from studies with animal models and with carriers of monogenic disorders affecting HDL-C levels in humans provide conflicting data about HDL being antiatherogenic. This review addresses the current state of knowledge regarding HDL based on these recent controversies
What Do the First 597 Global Fungal Red List Assessments Tell Us about the Threat Status of Fungi?
Fungal species are not immune to the threats facing animals and plants and are thus also prone to extinction. Yet, until 2015, fungi were nearly absent on the IUCN Red List. Recent efforts to identify fungal species under threat have significantly increased the number of published fungal assessments. The 597 species of fungi published in the 2022-1 IUCN Red List update (21 July 2022) are the basis for the first global review of the extinction risk of fungi and the threats they face. Nearly 50% of the assessed species are threatened, with 10% NT and 9% DD. For regions with a larger number of assessments (i.e., Europe, North America, and South America), subanalyses are provided. Data for lichenized and nonlichenized fungi are also summarized separately. Habitat loss/degradation followed by climate change, invasive species, and pollution are the primary identified threats. Bias in the data is discussed along with knowledge gaps. Suggested actions to address these gaps are provided along with a discussion of the use of assessments to facilitate on-the-ground conservation efforts. A research agenda for conservation mycology to assist in the assessment process and implementation of effective species/habitat management is presented
What Do the First 597 Global Fungal Red List Assessments Tell Us about the Threat Status of Fungi?
Fungal species are not immune to the threats facing animals and plants and are thus also prone to extinction. Yet, until 2015, fungi were nearly absent on the IUCN Red List. Recent efforts to identify fungal species under threat have significantly increased the number of published fungal assessments. The 597 species of fungi published in the 2022-1 IUCN Red List update (21 July 2022) are the basis for the first global review of the extinction risk of fungi and the threats they face. Nearly 50% of the assessed species are threatened, with 10% NT and 9% DD. For regions with a larger number of assessments (i.e., Europe, North America, and South America), subanalyses are provided. Data for lichenized and nonlichenized fungi are also summarized separately. Habitat loss/degradation followed by climate change, invasive species, and pollution are the primary identified threats. Bias in the data is discussed along with knowledge gaps. Suggested actions to address these gaps are provided along with a discussion of the use of assessments to facilitate on-the-ground conservation efforts. A research agenda for conservation mycology to assist in the assessment process and implementation of effective species/habitat management is presented
What Do the First 597 Global Fungal Red List Assessments Tell Us about the Threat Status of Fungi?
Fungal species are not immune to the threats facing animals and plants and are thus also prone to extinction. Yet, until 2015, fungi were nearly absent on the IUCN Red List. Recent efforts to identify fungal species under threat have significantly increased the number of published fungal assessments. The 597 species of fungi published in the 2022-1 IUCN Red List update (21 July 2022) are the basis for the first global review of the extinction risk of fungi and the threats they face. Nearly 50% of the assessed species are threatened, with 10% NT and 9% DD. For regions with a larger number of assessments (i.e., Europe, North America, and South America), subanalyses are provided. Data for lichenized and nonlichenized fungi are also summarized separately. Habitat loss/degradation followed by climate change, invasive species, and pollution are the primary identified threats. Bias in the data is discussed along with knowledge gaps. Suggested actions to address these gaps are provided along with a discussion of the use of assessments to facilitate on-the-ground conservation efforts. A research agenda for conservation mycology to assist in the assessment process and implementation of effective species/habitat management is presented
Conservation of Mediterranean oak woodlands: understorey dynamics under different shrub management
The effect of experimental disturbances
on the dynamics of a shrub community was studied
on a ‘Montado’ ecosystem, in southern Portugal. The
evolution of the community physiognomy, composition
and diversity were monitored after shrub clearing
followed by biomass removal, deposition on soil
surface and incorporation with the soil, over a 9-year
period. Maximum shrub density was recorded in the
first year after the disturbances, excepting in mulched
plots which showed the greatest number of individuals
1 year later. The increment of shrub leaf biomass
was very fast in the first 3 years, whereas wood
production was slower but occurred along the whole
study period. At the end of the study, leaf and wood
biomass was still significantly lower than in the predisturbance
situation. The variation pattern of leaf
area index was similar to that of leaf biomass. The
evolution of total plant cover and diversity was
similar across treatments. The highest species richness
and diversity were recorded 2 years after
cutting, decreasing afterwards with the increasing
dominance of shrubs. Thus it seems likely that,
although a 9 year period is too short for these
communities to reach steady equilibrium, they are
very resistant and resilient to disturbances, as regeneration
was fast and vegetation dynamics was not
influenced by differences among treatments. We can
conclude that shrub clearing promotes biodiversity
and the time of permanence of shrub patches depends
on the particular goal we want to achieve
Conservation of Mediterranean oak woodlands: understorey dynamics under different shrub management
The effect of experimental disturbances
on the dynamics of a shrub community was studied
on a ‘Montado’ ecosystem, in southern Portugal. The
evolution of the community physiognomy, composition
and diversity were monitored after shrub clearing
followed by biomass removal, deposition on soil
surface and incorporation with the soil, over a 9-year
period. Maximum shrub density was recorded in the
first year after the disturbances, excepting in mulched
plots which showed the greatest number of individuals
1 year later. The increment of shrub leaf biomass
was very fast in the first 3 years, whereas wood
production was slower but occurred along the whole
study period. At the end of the study, leaf and wood
biomass was still significantly lower than in the predisturbance
situation. The variation pattern of leaf
area index was similar to that of leaf biomass. The
evolution of total plant cover and diversity was
similar across treatments. The highest species richness
and diversity were recorded 2 years after
cutting, decreasing afterwards with the increasing
dominance of shrubs. Thus it seems likely that,
although a 9 year period is too short for these
communities to reach steady equilibrium, they are
very resistant and resilient to disturbances, as regeneration
was fast and vegetation dynamics was not
influenced by differences among treatments. We can
conclude that shrub clearing promotes biodiversity
and the time of permanence of shrub patches depends
on the particular goal we want to achieve