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1.
Ecol Evol ; 9(19): 11000-11009, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31641450

RESUMEN

The combination of ocean acidification (OA) and global warming is expected to have a significant effect on the diversity and functioning of marine ecosystems, particularly on calcifying algae such as rhodoliths (maërl) that form extensive beds worldwide, from polar to tropical regions. In addition, the increasing frequency of extreme events, such as heat waves, threatens coastal ecosystems and may affect their capacity to fix blue carbon. The few studies where the simultaneous effects of both temperature and CO2 were investigated have revealed contradictory results. To assess the effect that high temperature spells can have on the maërl beds under OA, we tested the short-time effects of temperature and CO2 on the net photosynthesis, respiration, and calcification of the recently described species Phymatolithon lusitanicum, the most common maërl species of southern Portugal. Photosynthesis, calcification, and respiration increased with temperature, and the differences among treatments were enhanced under high CO2. We found that in the short term, the metabolic rates of Phymatolithon lusitanicum will increase with CO2 and temperature as will the coupling between calcification and photosynthesis. However, under high CO2, this coupling will favor photosynthesis over calcification, which, in the long term, can have a negative effect on the blue carbon fixing capacity of the maërl beds from southern Portugal.

2.
Ecol Evol ; 8(10): 4781-4792, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29876057

RESUMEN

Mäerl/rhodolith beds are protected habitats that may be affected by ocean acidification (OA), but it is still unclear how the availability of CO 2 will affect the metabolism of these organisms. Some of the inconsistencies found among OA experimental studies may be related to experimental exposure time and synergetic effects with other stressors. Here, we investigated the long-term (up to 20 months) effects of OA on the production and calcification of the most common mäerl species of southern Portugal, Phymatolithon lusitanicum. Both the photosynthetic and calcification rates increased with CO 2 after the first 11 months of the experiment, whereas respiration slightly decreased with CO 2. After 20 months, the pattern was reversed. Acidified algae showed lower photosynthetic and calcification rates, as well as lower accumulated growth than control algae, suggesting that a metabolic threshold was exceeded. Our results indicate that long-term exposure to high CO 2 will decrease the resilience of Phymatolithon lusitanicum. Our results also show that shallow communities of these rhodoliths may be particularly at risk, while deeper rhodolith beds may become ocean acidification refuges for this biological community.

3.
PeerJ ; 4: e2503, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27703853

RESUMEN

Most ocean acidification (OA) experimental systems rely on pH as an indirect way to control CO2. However, accurate pH measurements are difficult to obtain and shifts in temperature and/or salinity alter the relationship between pH and pCO2. Here we describe a system in which the target pCO2 is controlled via direct analysis of pCO2 in seawater. This direct type of control accommodates potential temperature and salinity shifts, as the target variable is directly measured instead of being estimated. Water in a header tank is permanently re-circulated through an air-water equilibrator. The equilibrated air is then routed to an infrared gas analyzer (IRGA) that measures pCO2 and conveys this value to a Proportional-Integral-Derivative (PID) controller. The controller commands a solenoid valve that opens and closes the CO2 flush that is bubbled into the header tank. This low-cost control system allows the maintenance of stabilized levels of pCO2 for extended periods of time ensuring accurate experimental conditions. This system was used to study the long term effect of OA on the coralline red algae Phymatolithon lusitanicum. We found that after 11 months of high CO2 exposure, photosynthesis increased with CO2 as opposed to respiration, which was positively affected by temperature. Results showed that this system is adequate to run long-term OA experiments and can be easily adapted to test other relevant variables simultaneously with CO2, such as temperature, irradiance and nutrients.

4.
Environ Manage ; 57(3): 740-52, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26616429

RESUMEN

An international multi-disciplinary group of 24 researchers met to discuss ocean acidification (OA) during the Brazilian OA Network/Surface Ocean-Lower Atmosphere Study (BrOA/SOLAS) Workshop. Fifteen members of the BrOA Network (www.broa.furg.br) authored this review. The group concluded that identifying and evaluating the regional effects of OA is impossible without understanding the natural variability of seawater carbonate systems in marine ecosystems through a series of long-term observations. Here, we show that the western South Atlantic Ocean (WSAO) lacks appropriate observations for determining regional OA effects, including the effects of OA on key sensitive Brazilian ecosystems in this area. The impacts of OA likely affect marine life in coastal and oceanic ecosystems, with further social and economic consequences for Brazil and neighboring countries. Thus, we present (i) the diversity of coastal and open ocean ecosystems in the WSAO and emphasize their roles in the marine carbon cycle and biodiversity and their vulnerabilities to OA effects; (ii) ongoing observational, experimental, and modeling efforts that investigate OA in the WSAO; and (iii) highlights of the knowledge gaps, infrastructure deficiencies, and OA-related issues in the WSAO. Finally, this review outlines long-term actions that should be taken to manage marine ecosystems in this vast and unexplored ocean region.


Asunto(s)
Ciclo del Carbono , Ecosistema , Agua de Mar/química , Océano Atlántico , Atmósfera , Biodiversidad , Brasil , Dióxido de Carbono/análisis , Carbonatos , Humanos , Océanos y Mares
5.
Medicina (B Aires) ; 75(1): 41-3, 2015.
Artículo en Español | MEDLINE | ID: mdl-25637899

RESUMEN

Familial partial lipodystrophy (FPL) type 1 is a syndrome characterized by loss of subcutaneous fat in arms and legs and an excess of body fat in face, neck, and torso. This rare syndrome is usually diagnosed when patients present cardiovascular complications or pancreatitis due to the severe metabolic abnormalities. Here we present the case of a 45 year old diabetic female without any pathological family history, a poor glycemic control (HbA1c 11.7%), hypertriglideridemia (3000 mg/dl), a body mass index (BMI) of 38, thin limbs, subcutaneous fat loss in gluteal area and ledge of fat above them, prominent veins in lower extremities, moon face, and acanthosis nigricans; as well as hypertension (150/100 mmHg) and subcutaneous folds measuring less than average were observed. Hypercortisolism was discarded and leptin levels were measured (16.8 mg/ml, VR: BMI > 30: 50 mg/ml). Due to these clinical and biochemical manifestations, and low leptin levels (16.8 mg/ml), Kobberling syndrome was suspected; however, LMNA mutation analysis was negative. Changes in lifestyle and treatment with fenofibrate, biphasic insulin 50/50, and enalapril were initiated showing a a significant metabolic improvement: HbA1c (7.8%) and TG (243 mg/dl). FPL type 1 is a familial disease, although there are spontaneous cases. No specific mutation is responsible for this syndrome. Due to its clinical manifestations, Cushing syndrome must be discarded.


Asunto(s)
Lipodistrofia Parcial Familiar/diagnóstico , Grasa Subcutánea/patología , Acantosis Nigricans/complicaciones , Brazo , Nalgas , Diagnóstico Diferencial , Femenino , Humanos , Lipodistrofia Parcial Familiar/complicaciones , Persona de Mediana Edad , Enfermedades Raras/complicaciones , Enfermedades Raras/diagnóstico
6.
Medicina (B.Aires) ; 75(1): 41-43, Feb. 2015. ilus
Artículo en Español | LILACS | ID: lil-750510

RESUMEN

La lipodistrofia parcial familiar de tipo1 (LPF 1) es un síndrome caracterizado por la pérdida parcial de grasa subcutánea en extremidades con distribución incrementada de la misma en rostro, cuello y tronco. Es una identidad familiar aunque hay casos espontáneos. Hasta ahora no se conoce mutación responsable. Se debe realizar diagnóstico diferencial con el síndrome de Cushing. Es un síndrome poco frecuente y en oportunidades se llega al diagnóstico cuando los pacientes presentan complicaciones cardiovasculares o afectación pancreática como consecuencia de una grave alteración metabólica. Se presenta el caso de una paciente de 45 años con diabetes mellitus desde los 20 años de edad, mal control glucémico (HbA1c: 11.7%) e hipertrigliceridemia (TG: 3000 mg/dl), índice de masa corporal (IMC): 38, extremidades adelgazadas, pérdida de grasa subcutánea en glúteos, sobreelevación de pliegue por encima de los mismos, venas prominentes en miembros inferiores, cara de luna llena y marcada acantosis nigricans, hipertensión (TA: 150/100 mm Hg) y medidas de pliegues subcutáneos disminuidos. El dosaje de leptina fue 16.8 mg/ml. El estudio genético para gen LMNA fue negativo. Se instauraron medidas de cambio de estilo de vida, tratamiento con fenofibrato, insulina premezcla 50/50 y enalapril, obteniéndose una franca mejoría clínica, de la HbA1c (7.8%) y de los TG (243 mg/dl).


Familial partial lipodystrophy (FPL) type 1 is a syndrome characterized by loss of subcutaneous fat in arms and legs and an excess of body fat in face, neck, and torso. This rare syndrome is usually diagnosed when patients present cardiovascular complications or pancreatitis due to the severe metabolic abnormalities. Here we present the case of a 45 year old diabetic female without any pathological family history, a poor glycemic control (HbA1c 11.7%), hypertriglideridemia (3000 mg/dl), a body mass index (BMI) of 38, thin limbs, subcutaneous fat loss in gluteal area and ledge of fat above them, prominent veins in lower extremities, moon face, and acanthosis nigricans; as well as hypertension (150/100 mmHg) and subcutaneous folds measuring less than average were observed. Hypercortisolism was discarded and leptin levels were measured (16.8 mg/ml, VR: BMI > 30: 50 mg/ml). Due to these clinical and biochemical manifestations, and low leptin levels (16.8 mg/ml), Kobberling syndrome was suspected; however, LMNA mutation analysis was negative. Changes in lifestyle and treatment with fenofibrate, biphasic insulin 50/50, and enalapril were initiated showing a a significant metabolic improvement: HbA1c (7.8%) and TG (243 mg/dl). FPL type 1 is a familial disease, although there are spontaneous cases. No specific mutation is responsible for this syndrome. Due to its clinical manifestations, Cushing syndrome must be discarded.


Asunto(s)
Femenino , Humanos , Persona de Mediana Edad , Lipodistrofia Parcial Familiar/diagnóstico , Grasa Subcutánea/patología , Brazo , Acantosis Nigricans/complicaciones , Nalgas , Diagnóstico Diferencial , Lipodistrofia Parcial Familiar/complicaciones , Enfermedades Raras/complicaciones , Enfermedades Raras/diagnóstico
7.
Medicina (B.Aires) ; 75(1): 41-43, feb. 2015. ilus
Artículo en Español | BINACIS | ID: bin-134107

RESUMEN

La lipodistrofia parcial familiar de tipo1 (LPF 1) es un síndrome caracterizado por la pérdida parcial de grasa subcutánea en extremidades con distribución incrementada de la misma en rostro, cuello y tronco. Es una identidad familiar aunque hay casos espontáneos. Hasta ahora no se conoce mutación responsable. Se debe realizar diagnóstico diferencial con el síndrome de Cushing. Es un síndrome poco frecuente y en oportunidades se llega al diagnóstico cuando los pacientes presentan complicaciones cardiovasculares o afectación pancreática como consecuencia de una grave alteración metabólica. Se presenta el caso de una paciente de 45 años con diabetes mellitus desde los 20 años de edad, mal control glucémico (HbA1c: 11.7%) e hipertrigliceridemia (TG: 3000 mg/dl), índice de masa corporal (IMC): 38, extremidades adelgazadas, pérdida de grasa subcutánea en glúteos, sobreelevación de pliegue por encima de los mismos, venas prominentes en miembros inferiores, cara de luna llena y marcada acantosis nigricans, hipertensión (TA: 150/100 mm Hg) y medidas de pliegues subcutáneos disminuidos. El dosaje de leptina fue 16.8 mg/ml. El estudio genético para gen LMNA fue negativo. Se instauraron medidas de cambio de estilo de vida, tratamiento con fenofibrato, insulina premezcla 50/50 y enalapril, obteniéndose una franca mejoría clínica, de la HbA1c (7.8%) y de los TG (243 mg/dl).(AU)


Familial partial lipodystrophy (FPL) type 1 is a syndrome characterized by loss of subcutaneous fat in arms and legs and an excess of body fat in face, neck, and torso. This rare syndrome is usually diagnosed when patients present cardiovascular complications or pancreatitis due to the severe metabolic abnormalities. Here we present the case of a 45 year old diabetic female without any pathological family history, a poor glycemic control (HbA1c 11.7%), hypertriglideridemia (3000 mg/dl), a body mass index (BMI) of 38, thin limbs, subcutaneous fat loss in gluteal area and ledge of fat above them, prominent veins in lower extremities, moon face, and acanthosis nigricans; as well as hypertension (150/100 mmHg) and subcutaneous folds measuring less than average were observed. Hypercortisolism was discarded and leptin levels were measured (16.8 mg/ml, VR: BMI > 30: 50 mg/ml). Due to these clinical and biochemical manifestations, and low leptin levels (16.8 mg/ml), Kobberling syndrome was suspected; however, LMNA mutation analysis was negative. Changes in lifestyle and treatment with fenofibrate, biphasic insulin 50/50, and enalapril were initiated showing a a significant metabolic improvement: HbA1c (7.8%) and TG (243 mg/dl). FPL type 1 is a familial disease, although there are spontaneous cases. No specific mutation is responsible for this syndrome. Due to its clinical manifestations, Cushing syndrome must be discarded.(AU)

8.
Medicina (B Aires) ; 75(1): 41-3, 2015.
Artículo en Español | BINACIS | ID: bin-133811

RESUMEN

Familial partial lipodystrophy (FPL) type 1 is a syndrome characterized by loss of subcutaneous fat in arms and legs and an excess of body fat in face, neck, and torso. This rare syndrome is usually diagnosed when patients present cardiovascular complications or pancreatitis due to the severe metabolic abnormalities. Here we present the case of a 45 year old diabetic female without any pathological family history, a poor glycemic control (HbA1c 11.7


), hypertriglideridemia (3000 mg/dl), a body mass index (BMI) of 38, thin limbs, subcutaneous fat loss in gluteal area and ledge of fat above them, prominent veins in lower extremities, moon face, and acanthosis nigricans; as well as hypertension (150/100 mmHg) and subcutaneous folds measuring less than average were observed. Hypercortisolism was discarded and leptin levels were measured (16.8 mg/ml, VR: BMI > 30: 50 mg/ml). Due to these clinical and biochemical manifestations, and low leptin levels (16.8 mg/ml), Kobberling syndrome was suspected; however, LMNA mutation analysis was negative. Changes in lifestyle and treatment with fenofibrate, biphasic insulin 50/50, and enalapril were initiated showing a a significant metabolic improvement: HbA1c (7.8


) and TG (243 mg/dl). FPL type 1 is a familial disease, although there are spontaneous cases. No specific mutation is responsible for this syndrome. Due to its clinical manifestations, Cushing syndrome must be discarded.

9.
J Phycol ; 47(1): 118-22, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27021717

RESUMEN

Meadows of Halodule wrightii (Cymodoceaceae) underwent a decline in a tidal flat located at Paranaguá Bay (Parana, SE Brazil). This decline appeared to be related to an overgrowth of the epiphytic macroalga Hincksia mitchelliae (Harv.) P. C. Silva (Phaeophyceae). In order to characterize the type of epiphytism between the alga and its plant host, we compared two samples from the beginning and end of the algal overgrowth via electron and optical microscopes. The investigation revealed that at both sampling periods, there was an epiphytism of type II, which is due to an infection of epiphytes strongly attached to the surface of the host but not associated to any apparent direct host-tissue damage. The presence of plasmodesmata between the cells of Hincksia only in the late stage of the host-epiphyte interaction indicated a change in the vegetative organization of Hincksia in relation to its host to improve nutrient absorption and distribution through the epiphyte cells. This is the first report on plasmodesmata in H. mitchelliae. The proposed mechanisms with which the algal epiphytes lead seagrasses to death are shadowing by adhesion on Halodule surface and disruption of its osmoregulatory system. Our findings have implications for the conservation and management strategies of seagrass ecosystems.

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