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1.
Clin Obstet Gynecol ; 59(3): 487-97, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27427827

RESUMO

The challenging nature of recurrent pregnancy loss (RPL) is multifactorial, but largely begins with determining who meets diagnostic criteria for RPL as definitions vary and frequently change. Many patients seek obstetrical intervention after losses, even if they do not meet the criteria for RPL, and even those strictly meeting criteria often present a conundrum as to the etiology of their condition. The contribution of hereditary thrombophilia to RPL, the impact of each disorder on the clotting cascade, available evidence regarding pregnancy outcomes, and current recommendations for evaluation and treatment is presented.


Assuntos
Aborto Habitual/genética , Trombofilia/genética , Fator V/genética , Feminino , Humanos , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Mutação , Gravidez , Primeiro Trimestre da Gravidez , Deficiência de Proteína C/complicações , Deficiência de Proteína C/genética , Deficiência de Proteína S/complicações , Deficiência de Proteína S/genética , Protrombina/genética , Trombofilia/complicações
2.
Ecology ; 91(7): 2070-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20715629

RESUMO

On a local scale, invasiveness of introduced species and invasibility of habitats together determine invasion success. A key issue in invasion ecology has been how to quantify the contribution of species invasiveness and habitat invasibility separately. Conventional approaches, such as comparing the differences in traits and/or impacts of species between native and/or invaded ranges, do not determine the extent to which the performance of invaders is due to either the effects of species traits or habitat characteristics. Here we explore the interaction between two of the most widespread earthworm invaders in the world (Asian Amynthas agrestis and European Lumbricus rubellus) and study the effects of species invasiveness and habitat invasibility separately through an alternative approach of "third habitat" in Tennessee, USA. We propose that feeding behaviors of earthworms will be critical to invasion success because trophic ecology of invasive animals plays a key role in the invasion process. We found that (1) the biomass and isotopic abundances (delta13C and delta15N) of A. agrestis were not impacted by either direct effects of L. rubellus competition or indirect effects of L. rubellus-preconditioned habitat; (2) A. agrestis disrupted the relationship between L. rubellus and soil microorganisms and consequently hindered litter consumption by L. rubellus; and (3) compared to L. rubellus, A. agrestis shifted its diet more readily to consume more litter, more soil gram-positive (G+) bacteria (which may be important for litter digestion), and more non-microbial soil fauna when soil microorganisms were depleted. In conclusion, A. agrestis showed strong invasiveness through its dietary flexibility through diet shifting and superior feeding behavior and its indirectly negative effect of habitat invasibility on L. rubellus via changes in the soil microorganism community. In such context, our results expand on the resource fluctuation hypothesis and support the superior competitor hypothesis. This work presents additional approaches in invasion ecology, provides some new dimensions for further research, and contributes to a greater understanding of the importance of interactions between multiple invading species.


Assuntos
Comportamento Alimentar/fisiologia , Oligoquetos/classificação , Oligoquetos/fisiologia , Árvores/fisiologia , Animais , Conservação de Recursos Energéticos , Demografia , Ecossistema , América do Norte
3.
Placenta ; 91: 59-65, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32174308

RESUMO

INTRODUCTION: Placental viral infections are associated with fetal inflammation and adverse pregnancy outcomes. However, there have been limited studies on how placental macrophages in the villous and adjacent fetal umbilical endothelial cells respond to a viral insult. This study aimed to evaluate the communication between Hofbauer cells (HBCs) and human umbilical vein endothelial cells (HUVECs) during a viral infection. METHODS: HBCs were either uninfected or infected with the γ-herpesvirus, MHV-68, and the conditioned medium (CM) collected. HUVECs were exposed to HBC CM and the levels of the pro-neutrophilic response markers: IL-8; E-selectin; intercellular adhesion molecule 1 (ICAM-1); and vascular adhesion molecule 1 (VCAM-1) measured by ELISA and qPCR. The role of HBC-derived IL-1ß was investigated using an IL-1ß blocking antibody (Ab) or IL-1 receptor antagonist (IL-1Ra). RESULTS: MHV-68 infection of HBCs induced a significant increase in IL-1ß secretion. CM from infected HBCs induced HUVEC expression of IL-8, E-selectin, VCAM-1, ICAM-1 mRNA, and secretion of IL-8. The HUVEC response to the CM of MHV-infected HBCs was inhibited by a neutralizing IL-1ß Ab and by IL-1Ra. DISCUSSION: Virally-induced HBC IL-1ß activates HUVECs to generate a pro-neutrophilic response. This novel cell-cell communication pathway may play an important role in the genesis of fetal inflammation associated with placental viral infection.


Assuntos
Células Endoteliais da Veia Umbilical Humana/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Placenta/metabolismo , Feminino , Herpesviridae , Células Endoteliais da Veia Umbilical Humana/virologia , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Macrófagos/virologia , Placenta/virologia , Gravidez , Molécula 1 de Adesão de Célula Vascular/metabolismo
4.
PLoS One ; 9(1): e84988, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24465460

RESUMO

Impacts of land use on soil organic C (SOC) are of interest relative to SOC sequestration and soil sustainability. The role of aggregate stability in SOC storage under contrasting land uses has been of particular interest relative to conventional tillage (CT) and no-till (NT) agriculture. This study compares soil structure and SOC fractions at the 30-yr-old Horseshoe Bend Agroecosystem Experiment (HSB). This research is unique in comparing NT and CT with adjacent land concurrently undergoing forest succession (FS) and in sampling to depths (15-28 cm) previously not studied at HSB. A soil moving experiment (SME) was also undertaken to monitor 1-yr changes in SOC and aggregation. After 30 years, enhanced aggregate stability under NT compared to CT was limited to a depth of 5 cm, while enhanced aggregate stability under FS compared to CT occurred to a depth of 28 cm and FS exceeded NT from 5-28 cm. Increases in SOC concentrations generally followed the increases in stability, except that no differences in SOC concentration were observed from 15-28 cm despite greater aggregate stability. Land use differences in SOC were explained equally by differences in particulate organic carbon (POC) and in silt-clay associated fine C. Enhanced structural stability of the SME soil was observed under FS and was linked to an increase of 1 Mg SOC ha(-1) in 0-5 cm, of which 90% could be attributed to a POC increase. The crushing of macroaggregates in the SME soil also induced a 10% reduction in SOC over 1 yr that occurred under all three land uses from 5-15 cm. The majority of this loss was in the fine C fraction. NT and FS ecosystems had greater aggregation and carbon storage at the soil surface but only FS increased aggregation below the surface, although in the absence of increased carbon storage.


Assuntos
Solo/química , Carbono , Conservação dos Recursos Naturais , Monitoramento Ambiental/métodos
5.
Nat Commun ; 4: 2576, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24129390

RESUMO

A recent review concluded that earthworm presence increases CO2 emissions by 33% but does not affect soil organic carbon stocks. However, the findings are controversial and raise new questions. Here we hypothesize that neither an increase in CO2 emission nor in stabilized carbon would entirely reflect the earthworms' contribution to net carbon sequestration. We show how two widespread earthworm invaders affect net carbon sequestration through impacts on the balance of carbon mineralization and carbon stabilization. Earthworms accelerate carbon activation and induce unequal amplification of carbon stabilization compared with carbon mineralization, which generates an earthworm-mediated 'carbon trap'. We introduce the new concept of sequestration quotient to quantify the unequal processes. The patterns of CO2 emission and net carbon sequestration are predictable by comparing sequestration quotient values between treatments with and without earthworms. This study clarifies an ecological mechanism by which earthworms may regulate the terrestrial carbon sink.


Assuntos
Dióxido de Carbono/metabolismo , Sequestro de Carbono/fisiologia , Carbono/metabolismo , Oligoquetos/metabolismo , Agricultura , Animais , Ecossistema , Solo/química
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