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1.
J Endocrinol ; 244(2): 415-429, 2020 02 01.
Article in English | MEDLINE | ID: mdl-32395971

ABSTRACT

Among all the hormone-secreting pituitary tumours, prolactinomas are the most frequently found in the clinic. Since dopamine is the primary inhibitor of lactotroph function, dopamine agonists represent the first-line therapy. However, a subset of patients exhibits resistance to these drugs, and therefore, alternative treatments are desired. As activins inhibit prolactin gene expression through the inhibition of Pit-1 involving the p38MAPK pathway, in the present work, we studied the local activin system as an alternative inhibitory system for lactotroph hyperplasia treatment. We used two different mouse models of prolactinoma: transgenic mice with overexpression of the human chorionic gonadotropin ß-subunit (hCGß) and mice lacking dopamine receptor type 2. In both models, females, but not males, develop lactotroph hyperplasia from the fourth month of life. We found reduced expression of pituitary activin subunits and activin receptors in hyperplastic pituitaries from both models compared with wild-type counterparts. Consequently, hyperplastic pituitaries presented a reduced activin-inhibitory action on prolactin secretion. Additionally, while female wild-type lactotrophs presented high levels of phospho-p38MAPK, it was lost in prolactinomas, concomitant with decreased activin expression, increased Pit-1 expression and tumour development. In contrast, male pituitaries express higher mRNA levels of activin subunits ßA and ßB, which would suggest a stronger activin inhibitory function on lactotrophs, protecting this sex from tumour development, despite genotype. The present results highlight the importance of the activin inhibitory action on lactotroph function and place the local activin system as a new target for the treatment of dopamine agonist-resistant prolactinomas.


Subject(s)
Activins/metabolism , Lactotrophs/metabolism , Pituitary Neoplasms/genetics , Prolactinoma/genetics , Animals , Dopamine Agonists/pharmacology , Drug Resistance, Neoplasm/genetics , Female , Genotype , MAP Kinase Signaling System/genetics , Male , Mice , Mice, Transgenic , Pituitary Gland/metabolism , Pituitary Neoplasms/complications , Pituitary Neoplasms/drug therapy , Prolactinoma/complications , Prolactinoma/drug therapy , RNA, Messenger/metabolism , Sex Factors , Transcription Factor Pit-1/metabolism
2.
Int J Phytoremediation ; 22(8): 863-871, 2020.
Article in English | MEDLINE | ID: mdl-32028785

ABSTRACT

The potential of Iris pseudacorus and Typha domingensis to remove the pharmaceutical active compound (PhAC) Furosemide from a nutrient solution was assessed. Both plants were exposed to 2 mg L-1 of furosemide during 21 days and the removal of furosemide was monitored. Vessels without furosemide were also implemented as control systems for plants development. Likewise, unplanted vessels with furosemide were employed to assess abiotic removal mechanisms. All vessels were covered with aluminum foil to avoid photodegradation of the compound. Both plants showed potential to remove Furosemide, attaining, at the end of the experiment, a removal of 42.0-66.9% and 40.5-57.8%, for Typha and Iris, respectively. The plants do not presented a visible negative stress response to the exposure to furosemide, having a positive growth rate at the end of the experiment. Biodegradation seems to play an important role in furosemide removal, being enhanced by the presence of the plants. The two macrophytes presented different removal behaviors, particularly in the first 48 h of contact time. FUR removal by Iris follows a pseudo-first order while by Typha is divide in different phases. These results indicate that different plants species seem to have different mechanisms to remove pollutants from water.HighlightsPhACs removal potential of Iris pseudacorus and Typha domingensis was assessed.Plants were exposed to 2 mg L-1 of furosemide during 21 days.Both macrophytes showed good removal efficiencies.Biodegradation of furosemide seems to be the main removal mechanism.Plants demonstrated different removal behavior along the experiment.Removal mechanisms of plants seem to differ between species.


Subject(s)
Typhaceae , Water Pollutants, Chemical , Biodegradation, Environmental , Furosemide , Hydroponics , Wetlands
3.
Sci Total Environ ; 705: 135843, 2020 Feb 25.
Article in English | MEDLINE | ID: mdl-31822414

ABSTRACT

Wildfires affect vast areas of Mediterranean forests, thereby triggering changes in hydrological and geomorphological processes that can negatively affect both terrestrial and aquatic ecosystems. Although several studies have evaluated the post-fire hydrological and erosive response in burnt forest areas, an important knowledge gap remains with respect to nutrient mobilization by overland flow. To address this gap, a recently burnt area was selected near the Ermida village (north-central Portugal). The study area was instrumented shortly after a wildfire that occurred in July 2010, to evaluate the export of dissolved (nitrate - NO3-N and orthophosphate - PO4-P) and total nitrogen (TN) and phosphorus (TP) forms by overland flow. This was done in two burnt eucalyptus plantations due to their contrasting slope aspects (south-east vs. north-west). Bounded micro-plots were installed in August 2010 and monitored over two years. During this period, overland flow samples were collected on a 1- to 2-weekly basis, depending on the occurrence of rain. Results showed that the north west-facing slope (BE-N) presented higher nutrient losses than the south east-facing slope (BE-S), contradicting the findings of previous studies in the Mediterranean region. A logging operation that had taken place at the BE-N site shortly before the fire might account for these findings, by causing soil compaction and/or reducing the protective vegetation and litter cover. TN and TP exports were particularly pronounced during the first four months following the wildfire. After this initial period, further peaks in TN and TP exports occurred sporadically, mainly associated to intense rainfall events. The observed mid-term post-fire nutrient losses not only suggested a threat to the soil nutrient balance of Mediterranean eucalypt forests but also a potential risk of eutrophication of downstream water bodies.


Subject(s)
Nitrogen/analysis , Phosphorus/analysis , Ecosystem , Mediterranean Region , Portugal
4.
J Environ Manage ; 203(Pt 1): 422-428, 2017 Dec 01.
Article in English | MEDLINE | ID: mdl-28834775

ABSTRACT

The removal efficiency of LECA and cork granulates as support matrix for pharmaceuticals active compounds in a constructed wetland system was investigated using the diuretic drug Furosemide. Kinetics studies were performed testing three different concentrations of Furosemide in an ultrapure water matrix, along seven days. LECA achieved higher removal values compared to cork granulates. However, cork granulates presented a higher removal in the first 24 h of contact time compared to the other adsorbent. The kinetic studies showed that LECA and cork granulates have different adsorption behaviours for Furosemide which is controlled by different adsorption mechanisms. Both materials showed good removal efficiencies and a combination of the two should be further explored in order to applied both materials as support matrix to cope with different furosemide concentrations.


Subject(s)
Furosemide , Water Pollutants, Chemical , Wetlands , Kinetics , Waste Disposal, Fluid , Water Purification
5.
J Environ Manage ; 187: 560-570, 2017 Feb 01.
Article in English | MEDLINE | ID: mdl-27865730

ABSTRACT

Conventional wastewater treatment plants (WWTPs) commonly require large capital investments as well as operation and maintenance costs. Constructed wetlands (CWs) appear as a cost-effective treatment, since they can remove a broad range of contaminants by a combination of physical, chemical and biological processes with a low cost. Therefore, CWs can be successfully applied for decentralized wastewater treatment in regions with low population density and/or with large land availability as Brazil. The present work provides a review of thirty nine studies developed on CWs implemented in Brazil to remove wastewater contaminants. Brazil current sanitation data is also considered to evaluate the potential role of CWs as decentralized wastewater treatment. Performance of CWs was evaluated according to (i) type of wetland system, (ii) different support matrix (iii) vegetation species and (iv) removal efficiency of chemical oxygen demand (COD), biological oxygen demand (BOD5), nitrogen (N), and phosphorus (P). The reviewed CWs in overall presented good efficiencies, whereas H-CWs achieved the highest removals for P, while the higher results for N were attained on VF-CW and for COD and BOD5 on HF-CW. Therefore, was concluded that CWs are an interesting solution for decentralized wastewater treatment in Brazil since it has warm temperatures, extensive radiation hours and available land. Additionally, the low percentage of population with access to the sewage network in the North and Northeast regions makes these systems especially suitable. Hence, the further implementation of CW is encouraged by the authors in regions with similar characteristics as Brazil.


Subject(s)
Waste Disposal, Fluid , Wastewater , Water Purification , Wetlands , Biodegradation, Environmental , Brazil , Humans , Waste Disposal, Fluid/methods , Water Purification/methods
6.
Sci Total Environ ; 573: 1232-1241, 2016 Dec 15.
Article in English | MEDLINE | ID: mdl-27156440

ABSTRACT

Since the mid of the last century, fire recurrence has increased in the Iberian Peninsula and in the overall Mediterranean basin due to changes in land use and climate. The warmer and drier climate projected for this region will further increase the risk of wildfire occurrence and recurrence. Although the impact of wildfires on soil nutrient content in this region has been extensively studied, still few works have assessed this impact on the basis of fire recurrence. This study assesses the changes in soil organic C and nutrient status of mineral soils in two Southern European areas, Várzea (Northern Portugal) and Valencia (Eastern Spain), affected by different levels of fire recurrence and where short fire intervals have promoted a transition from pine woodlands to shrublands. At the short-term (<1year), the amount of soil organic matter was higher in burned than in unburned soils while its quality (represented as labile to total organic matter) was actually lower. In any case, total and labile soil organic matter showed decreasing trends with increasing fire recurrence (one to four fires). At the long-term (>5years), a decline in overall soil fertility with fire recurrence was also observed, with a drop between pine woodlands (one fire) and shrublands (two and three fires), particularly in the soil microsites between shrubs. Our results suggest that the current trend of increasing fire recurrence in Southern Europe may result in losses or alterations of soil organic matter, particularly when fire promotes a transition from pine woodland to shrubland. The results also point to labile organic matter fractions in the intershrub spaces as potential early warning indicators for shifts in soil fertility in response to fire recurrence.

7.
Sci Total Environ ; 572: 1281-1288, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-26765507

ABSTRACT

Over the past decades, wildfires have affected extensive areas of the Mediterranean region with negative impacts on the environment. Most of the studies on fire-affected areas have focused on sediment losses by overland flow, whereas few have addressed post-fire nutrient export. The present study aimed to address this research gap by assessing nitrogen (nitrate and total nitrogen) losses by overland flow in a recently burnt area in north-central Portugal. To this end, three burnt slopes were selected for their contrasting forest types (eucalypt vs. pine) and parent materials (granite vs. schist). The selected study sites were a eucalypt site on granite (BEG), a eucalypt site on schist (BES) and a maritime pine site on schist (BPS). Overland flow samples were collected during the first six months after the wildfire on a 1- to 2-weekly basis, after which this study had to be cancelled due to bench terracing of some of the sites. A peak in total nitrogen concentrations was observed in burnt areas immediately after the first post-fire rainfall event as a response to the erosion of the N-enriched ash layer. After this initial peak, smaller peaks were observed throughout the study period, mainly as a response to overland flow and/or erosion events. Nitrogen export differed strikingly between the two types of forests on schist, being higher at the eucalypt than at the pine site, due to the lack of a protective soil layer. Parent material did not play an important role on nitrogen export by overland flow since no significant differences were found between the eucalypt sites on granite and schist. The present study provides some insight into the differences in post-fire soil fertility losses between forest types and parent materials in the Mediterranean region, which is crucial information for defining post-fire land management measures to reduce soil degradation.

8.
Sci Total Environ ; 524-525: 201-12, 2015 Aug 15.
Article in English | MEDLINE | ID: mdl-25897728

ABSTRACT

The current fire regime in the Mediterranean Basin constitutes a serious threat to natural ecosystems because it drastically enhances surface runoff and soil erosion in the affected areas. Besides soil particles themselves, soil cations can be lost by fire-enhanced overland flow, increasing the risk of fertility loss of the typically shallow and nutrient poor Mediterranean soils. Although the importance of cations for land-use sustainability is widely recognized, cation losses by post-fire runoff have received little research attention. The present study aimed to address this research gap by assessing total exports of Na(+), K(+), Ca(2+) and Mg(2+) in a recently burnt forest area in north-central Portugal. These exports were compared for two types of planted forest (eucalypt vs. maritime pine plantations), two types of parent materials (schist vs. granite) and for two spatial scales (micro-plot vs. hill slope). The study sites were a eucalypt plantation on granite (BEG), a eucalypt plantation on schist (BES) and a maritime pine plantation on schist (BPS). Overland flow samples were collected during the first six months after the wildfire. Cation losses differed strikingly between the two forest types on schist, being higher at the eucalypt than pine site. This difference was evident at both spatial scales, and probably due to the extensive cover of a needle cast from the scorched pine crowns. The role of parent material in cation export was less straightforward as it varied with spatial scale. Cation losses were higher for the eucalypt plantation on schist than for that on granite at the micro-plot scale, whereas the reverse was observed at the hill slope scale. Finally, cation yields were higher at the micro-plot than slope scale, in agreement with the general notion of scaling-effect in runoff generation.


Subject(s)
Cations/analysis , Environmental Monitoring , Fires , Forests , Conservation of Natural Resources , Ecosystem , Portugal
9.
Prog. diagn. trat. prenat. (Ed. impr.) ; 21(1): 44-48, ene.-mar. 2009. ilus
Article in Spanish | IBECS | ID: ibc-76789

ABSTRACT

A existência de uma mola hidatiforme completa coexistentecom feto vivo, numa gravidez gemelar, é uma entidaderara. A atitude clínica constitui um desafio uma vez que amanutenção da gravidez de modo a alcançar a viabilidadefetal pode associar-se a potenciais complicações fetais e/oumaternas graves, tais como hemorragia vaginal, pré-eclâmpsia,morte fetal, prematuridade e risco aumentado de doençatrofoblástica persistente, condicionando um verdadeirodilema clínico, mãe/feto.Os autores descrevem o caso de uma mulher de 35 anos,admitida às 24 semanas de gestação por hemorragia vaginalpersistente numa gravidez gemelar bicoriónica, com umadas placentas com feto normal e outra placenta prévia total,compatível com mola hidatiforme completa. Apresentava,concomitantemente, hipertiroidismo subclínico. A gravidezfoi vigiada com atitude expectante até às 27 semanas degestação, altura em que após episódio grave de hemorragiavaginal, realizou-se cesariana com extracção de nado vivocom 947 g. Os níveis séricos da subunidade β da hormonagonadotrofina coriónica humana (β-hGC) negativaram nadécima quarta semana após o parto.A clínica, os níveis séricos de β-hGC e as imagens ecográficassugeriram o diagnóstico de mola hidatiforme completa,os quais foram corroborados pelos estudos citogenéticos (AU)


A twin pregnancy with a coexisting complete hydatiformmole and a healthy fetus is a rare event. The ma-Casos clínicosMola hidatiforme completa préviacoexistente com feto vivo numagravidez gemelar bicoriónica1 Serviço de Medicina Materno Fetal2 Centro de Diagnóstico Pré-Natal3 Serviço de Anatomia PatológicaMaternidade Dr. Alfredo da CostaLisboa (Portugal)4 Unidade de CitogenéticaDepartamento de Genética HumanaInstituto Nacional de Saúde Dr. Ricardo Jorge, INSA, I.PLisboa (Portugal)T. Sardinha1A. I. Machado1E. Dias1L. Martins2I. Biscaia3H. Correia4F. Serrano1J. Correia2A. Campos1nagement is challenging because although the fetus maybe viable, maintaining the pregnancy is associated withpotentially serious maternal and fetal complications, likevaginal bleeding, pre-eclampsia, preterm delivery, fetaldeath and an increased risk of persistent gestational trophoblasticdisease, which leads us to a clear mother versusfetus clinical dilemma.We describe a case of a 35-year-old woman who wasadmitted for persistent vaginal bleeding in a 24 weeks bichorionictwin pregnancy, one placenta with a normal fetusand the other, a complete placenta praevia,compatible with a complete hydatiform mole. She alsopresented subclinical hyperthyroidism. The pregnancywas managed conservatively until 27 weeks gestationwhen, following an episode of major antepartum haemorrhage,a 947-g live was delivered by Caesarean Section.Serum human chorionic gonadotrophin β-subunit(β-hCG) concentrations returned to baseline fourteen weeksfollowing delivery.The clinical, the serum β-hCG concentrations and theultrasound suggested the diagnosis of a complete hydatiformmole but it was the cytogenetic studies that confirmed it (AU)


Subject(s)
Humans , Female , Pregnancy , Adult , Diseases in Twins/diagnosis , Hydatidiform Mole/diagnosis , Uterine Hemorrhage , Cesarean Section
10.
Arch Gynecol Obstet ; 280(2): 297-300, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19107501

ABSTRACT

SETTING: Burkitt's lymphoma is a rare form of cancer and is an extremely rare diagnosis during pregnancy. This form of lymphoma is a very fast growing B cell neoplasm and chemotherapy is the treatment of choice for the disease in all its stages. CASE REPORT: The authors describe the case of a Caucasian 40-year-old nulliparous woman, with previous known Epstein-Barr virus infection, that presents at 28 weeks gestation with supraclavicular adenopathy and multiple bilateral breast nodules, in which biopsy showed non-Hodgkin lymphoma, Burkitt's type. DISCUSSION: There are few described cases of Burkitt's lymphoma during pregnancy and in general the outcomes have been poor. In most of the cases, the patients were not treated by current standards or instead had a late diagnosis. This neoplasia is the most rapidly progressive human tumor, and any delay in initiating therapy can adversely affect patient's prognosis. The authors discuss treatment options in pregnancy and its perinatal implications.


Subject(s)
Burkitt Lymphoma/virology , Epstein-Barr Virus Infections/complications , Pregnancy Complications, Neoplastic/virology , Adult , Antineoplastic Agents/therapeutic use , Antineoplastic Combined Chemotherapy Protocols , Burkitt Lymphoma/drug therapy , Female , Humans , Pregnancy , Pregnancy Complications, Infectious , Pregnancy Complications, Neoplastic/drug therapy
11.
Prog. diagn. trat. prenat. (Ed. impr.) ; 17(4): 196-198, dic. 2005. ilus
Article in Es | IBECS | ID: ibc-69975

ABSTRACT

Las anomalías conotruncales y del arco aórtico pueden estar asociadas a microdelecciones 22q11, lo cual conlleva un riesgo aumentado de otras anomalías, incluyendo déficit de desarrollo mental. Se presenta un caso de diagnóstico prenatal de microdelección 22q11 en un feto con arco aórtico derecho como único defecto estructural, detectado en la ecografía rutinaria buscando la imagen de los tres vasos y tráquea. Se discute la posterior conducta y el pronóstico basado en casos similares en la literatura médica


Conotruncal and aortic arch anomalies can be associated with a 22q11 microdeletion which accounts an elevated risk of extra cardiac anomalies including mental impairment. The authors present a case of a prenatal diagnosis of a 22q11 deletion in a fetus with right aortic arch as the only structural defect. This cardiac defect was detected in the routine exam on the «three-vessel-trachea» view. They discuss the subsequent management and prognosis based on similar cases in the literature


Subject(s)
Humans , Female , Pregnancy , Adult , Chromosome Deletion , Aortic Arch Syndromes , Prenatal Diagnosis/methods
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