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1.
AIDS Res Ther ; 21(1): 4, 2024 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-38185696

RESUMEN

BACKGROUND: There is limited data on dolutegravir (DTG)-associated weight gain from settings with a dual burden of HIV and overnutrition. METHODS: In Eswatini (at Matsanjeni), among 156 and 160 adult patients on DTG-based and EFV-based antiretroviral therapy (ART), respectively, we studied excessive weight gain (BMI at 24 months ART greater than baseline and ≥25 kg/m2). RESULTS: The median BMI increase in DTG-based patients was 1.09 (IQR:-0.28,3.28) kg/m2 compared to 0.20 (IQR:-0.85,2.18) kg/m2 in EFV-based patients (p value = 0.001). DTG-based ART predicted excessive weight gain (aOR 2.61;95% CI:1.39-4.93). CONCLUSION: Practitioners should consider DTG-based regimens as one of the risk factors for overweight/obesity.


Asunto(s)
Infecciones por VIH , Adulto , Humanos , Infecciones por VIH/tratamiento farmacológico , Esuatini , Estudios Retrospectivos , Benzoxazinas/uso terapéutico , Aumento de Peso
2.
Int J Tuberc Lung Dis ; 27(11): 803-809, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37880892

RESUMEN

Air pollution is an environmental risk for the general population and for patients with various diseases, particularly respiratory diseases. Little data are available on personal exposure, but the recent emergence of low-cost air quality sensors (LCSs) should enable a better understanding of the health impacts of air pollution at the individual level. However, the reliability and accuracy of most sensors in the market have not been established, and a thorough understanding of their strengths and limitations is needed. We therefore conducted a review to address the following questions: 1) What is an LCS and what is the extent of its possible application? 2) Is the data obtained a reliable indicator of exposure? 3) What are the advantages and disadvantages of LCSs? 4) Could LCSs be useful in investigating the impact of air pollution on respiratory health? Further studies are needed to promote the use of LCS in research settings and among respiratory patients. This will allow us to monitor exposure levels, provide alerts and study the respiratory effects of individual-level air pollution.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Enfermedades Respiratorias , Humanos , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Reproducibilidad de los Resultados , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Enfermedades Respiratorias/diagnóstico , Monitoreo del Ambiente , Material Particulado/efectos adversos , Material Particulado/análisis
3.
Surg Radiol Anat ; 45(12): 1567-1577, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37884742

RESUMEN

BACKGROUND: Clinical exam is the goldstandard for surgical indication. ENMG and conventional MRI are insufficient to understand the highly variable clinical presentation of brachial plexus (BP) lesions. DTI is based on motion of water molecules and can explore nerve function. PURPOSE: This pilot study of healthy subjects aimed to develop RESOLVE sequence for BP exploration using diffusion MRI. The main objective was to provide complete precise information from DTI cartography associated with anatomical data. METHODS: Six healthy volunteers were scanned using 3T PRISMA scanner with anatomic 3D STIR SPACE and RESOLVE diffusion sequences. Diffusion parametric maps of fractional anisotropy (FA) were extracted from RESOLVE acquisitions. A reproducible method for roots volumes and angles measurements was created using 3DSlicer. ROI were segmented on Mean B0 sequences. FA measurements were obtained with ROI on Mean B0 sequences. RESULTS: RESOLVE sequence was adapted to the BP. Mean FA was 0.30. Angles measurements on 3D STIR SPACE sequences showed increasing values from proximal to distal roots with an 0.6 ICC. Volume measurements on anatomic sequences varied widely from one root to another but did not show any significant difference on laterality. CONCLUSIONS: A new and reproducible method for BP exploration was developed, using MRI RESOLVE DTI sequences. Complete mapping was obtained but a low resolution of track density imaging did not allow to exploit distal nerves. Deterministic tractography principal limit was the lack of resolution. Extraction of diffusion, volumetric and angular parameters of the plexus roots, and scripts creation for image processing was adapted to the healthy BP.


Asunto(s)
Plexo Braquial , Imagen de Difusión Tensora , Humanos , Imagen de Difusión Tensora/métodos , Proyectos Piloto , Imagen por Resonancia Magnética , Imagen de Difusión por Resonancia Magnética , Plexo Braquial/diagnóstico por imagen , Anisotropía
4.
Vector Borne Zoonotic Dis ; 21(8): 593-601, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34129392

RESUMEN

Malaria vectors are supposedly uncommon in urban areas owing to the lack of suitable breeding sites for their development. However, the maintenance in urban areas of traditional rural practices along with humanitarian crisis can create favorable conditions for malaria transmission. This study aimed to provide relevant entomological data on the risk of malaria transmission in the city of Bouaké, after the military-political crisis from 2002 to 2011 in Côte d'Ivoire. Adults mosquitoes were collected by human landing catches in Dar Es Salam, Kennedy and N'gattakro neighborhoods. Potential breeding sites were georeferenced and mapped using a GPS. Mosquito species were identified morphologically and by molecular methods. Plasmodium infections were detected by quantitative PCR. Anopheline larvae were found in rice and vegetable crops, puddles, and footprints. A total of 939 Anopheles gambiae s.l. were caught during the surveys. The average human biting rate was 8.8 bites/person/night. The A. gambiae s.l. species were A. gambiae s.s (89.6%) and Anopheles coluzzii (10.4%). The average infectivity rate was 0.74% and the average annual entomological inoculation rate was estimated at 19 infected bites/person/year ranging from 0 in Dar Es Salam and N'gattakro to 58 in Kennedy. The risk of malaria transmission exists in Bouaké city, although Plasmodium infections are low.


Asunto(s)
Anopheles , Malaria , Animales , Côte d'Ivoire/epidemiología , Ecosistema , Larva , Malaria/epidemiología , Malaria/veterinaria , Mosquitos Vectores , Fitomejoramiento
5.
Biol Open ; 10(6)2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-34100899

RESUMEN

Genetic studies have linked FAT1 (FAT atypical cadherin 1) with autism spectrum disorder (ASD); however, the role that FAT1 plays in ASD remains unknown. In mice, the function of Fat1 has been primarily implicated in embryonic nervous system development with less known about its role in postnatal development. We show for the first time that FAT1 protein is expressed in mouse postnatal brains and is enriched in the cerebellum, where it localizes to granule neurons and Golgi cells in the granule layer, as well as inhibitory neurons in the molecular layer. Furthermore, subcellular characterization revealed FAT1 localization in neurites and soma of granule neurons, as well as being present in the synaptic plasma membrane and postsynaptic densities. Interestingly, FAT1 expression was decreased in induced pluripotent stem cell (iPSC)-derived neural precursor cells (NPCs) from individuals with ASD. These findings suggest a novel role for FAT1 in postnatal development and may be particularly important for cerebellum function. As the cerebellum is one of the vulnerable brain regions in ASD, our study warrants further investigation of FAT1 in the disease etiology.


Asunto(s)
Trastorno Autístico/etiología , Cadherinas/genética , Susceptibilidad a Enfermedades , Animales , Trastorno Autístico/metabolismo , Biomarcadores , Cadherinas/metabolismo , Cerebelo/metabolismo , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Hipocampo/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Interneuronas/metabolismo , Ratones , Neuritas/metabolismo , Transporte de Proteínas , Transcriptoma
6.
Transpl Infect Dis ; 23(4): e13658, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34057799

RESUMEN

Herpes Zoster (HZ) is caused by reactivation of latent varicella zoster virus (VZV) in craniospinal sensory neurons and is characterized by a painful erythematous rash in the affected dermatome. Although kidney transplant recipients who are chronically maintained on immunosuppressive regimens are considered at risk, there are only a few cases described. We report a well-documented case of a 50-year-old male kidney transplant recipient who presented Ramsay-Hunt syndrome with atypical neurological finds.


Asunto(s)
Herpes Zóster Ótico , Herpes Zóster , Trasplante de Riñón , Herpes Zóster Ótico/diagnóstico , Herpes Zóster Ótico/tratamiento farmacológico , Herpesvirus Humano 3 , Humanos , Inmunosupresores/efectos adversos , Trasplante de Riñón/efectos adversos , Masculino , Persona de Mediana Edad
7.
Science ; 367(6485): 1485-1489, 2020 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-32217728

RESUMEN

Disrupting North Atlantic Deep Water (NADW) ventilation is a key concern in climate projections. We use (sub)centennially resolved bottom water δ13C records that span the interglacials of the last 0.5 million years to assess the frequency of and the climatic backgrounds capable of triggering large NADW reductions. Episodes of reduced NADW in the deep Atlantic, similar in magnitude to glacial events, have been relatively common and occasionally long-lasting features of interglacials. NADW reductions were triggered across the range of recent interglacial climate backgrounds, which demonstrates that catastrophic freshwater outburst floods were not a prerequisite for large perturbations. Our results argue that large NADW disruptions are more easily achieved than previously appreciated and that they occurred in past climate conditions similar to those we may soon face.

8.
J Med Entomol ; 57(4): 1254-1261, 2020 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-31982912

RESUMEN

Studies done in Bouaké (Côte d'Ivoire) about 20-yr ago reported that Anopheles gambiae s.l. Giles was the major malaria vector. The present study aimed to update these data and to identify the main vectors. Mosquitoes were collected in Allokokro and Petessou villages between June 2014 and December 2015 using the human landing catching method. Potential breeding sites of An. gambiae s.l. were identified in August and October 2014 and mapped using GPS. Anopheles species were morphologically and molecularly [polymerase chain reaction (PCR)] identified. Ovaries of female were dissected to determine the parity and infection with Plasmodium was detected in head and thorax by quantitative PCR. In Allokokro, the biting rate of An. gambiae s.s was significantly greater than Anopheles coluzzii, whereas, in Petessou, biting rates of both species were comparable. Plasmodium falciparum (Haemosporida: Plasmodiidae), Plasmodium malariae (Haemosporida: Plasmodiidae), and Plasmodium ovale (Haemosporida: Plasmodiidae) identified in both villages. The infection rates of An. gambiae s.s. and An. coluzzii were not significantly different. The entomological inoculation rate (EIR) of An. gambiae s.s. for P. falciparum was 9-fold greater than that of An. coluzzii in Allokokro; however, in Petessou, the EIRs of both species were comparable. In both village, An. gambiae s.s was responsible for P. falciparum and P. ovale transmission whereas An. coluzzii transmitted all three Plasmodium species.


Asunto(s)
Anopheles/parasitología , Malaria/transmisión , Mosquitos Vectores/parasitología , Animales , Côte d'Ivoire , Humanos , Malaria Falciparum/transmisión , Plasmodium falciparum/aislamiento & purificación , Plasmodium malariae/aislamiento & purificación , Plasmodium ovale/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Población Rural
9.
Glob Chang Biol ; 25(12): 4092-4104, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31566878

RESUMEN

The capacity of coral reefs to maintain their structurally complex frameworks and to retain the potential for vertical accretion is vitally important to the persistence of their ecological functioning and the ecosystem services they sustain. However, datasets to support detailed along-coast assessments of framework production rates and accretion potential do not presently exist. Here, we estimate, based on gross bioaccretion and bioerosion measures, the carbonate budgets and resultant estimated accretion rates (EAR) of the shallow reef zone of leeward Bonaire - between 5 and 12 m depth - at unique fine spatial resolution along this coast (115 sites). Whilst the fringing reef of Bonaire is often reported to be in a better ecological condition than most sites throughout the wider Caribbean region, our data show that the carbonate budgets of the reefs and derived EAR varied considerably across this ~58 km long fringing reef complex. Some areas, in particular the marine reserves, were indeed still dominated by structurally complex coral communities with high net carbonate production (>10 kg CaCO3  m-2  year-1 ), high live coral cover and complex structural topography. The majority of the studied sites, however, were defined by relatively low budget states (<2 kg CaCO3  m-2  year-1 ) or were in a state of net erosion. These data highlight the marked spatial heterogeneity that can occur in budget states, and thus in reef accretion potential, even between quite closely spaced areas of individual reef complexes. This heterogeneity is linked strongly to the degree of localized land-based impacts along the coast, and resultant differences in the abundance of reef framework building coral species. The major impact of this variability is that those sections of reef defined by low-accretion rates will have limited capacity to maintain their structural integrity and to keep pace with current projections of climate change induced sea-level rise (SLR), thus posing a threat to reef functioning and biodiversity, potentially leading to trophic cascades. Since many Caribbean reefs are more severely degraded than those found around Bonaire, it is to be expected that the findings presented here are rather the rule than the exception, but the study also highlights the need for similar high spatial resolution (along-coast) assessments of budget states and accretion rates to meaningfully explore increasing coastal risk at the country level. The findings also more generally underline the significance of reducing local anthropogenic disturbance and restoring framework building coral assemblages. Appropriately focussed local preservation efforts may aid in averting future large-scale above reef water depth increases on Caribbean coral reefs and will limit the social and economic implications associated with the loss of reef goods and services.


Asunto(s)
Antozoos , Ecosistema , Animales , Carbonatos , Región del Caribe , Arrecifes de Coral , Humanos
10.
Nat Commun ; 10(1): 2549, 2019 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-31186409

RESUMEN

Human adipose tissue (hAT) is constituted of structural units termed lobules, the organization of which remains to be defined. Here we report that lobules are composed of two extracellular matrix compartments, i.e., septa and stroma, delineating niches of CD45-/CD34+/CD31- progenitor subsets characterized by MSCA1 (ALPL) and CD271 (NGFR) expression. MSCA1+ adipogenic subset is enriched in stroma while septa contains mainly MSCA1-/CD271- and MSCA1-/CD271high progenitors. CD271 marks myofibroblast precursors and NGF ligand activation is a molecular relay of TGFß-induced myofibroblast conversion. In human subcutaneous (SC) and visceral (VS) AT, the progenitor subset repartition is different, modulated by obesity and in favor of adipocyte and myofibroblast fate, respectively. Lobules exhibit depot-specific architecture with marked fibrous septa containing mesothelial-like progenitor cells in VSAT. Thus, the human AT lobule organization in specific progenitor subset domains defines the fat depot intrinsic capacity to remodel and may contribute to obesity-associated cardiometabolic risks.


Asunto(s)
Tejido Adiposo/anatomía & histología , Tejido Adiposo/citología , Nicho de Células Madre , Células Madre/citología , Adipocitos/metabolismo , Adipogénesis , Fosfatasa Alcalina , Diferenciación Celular , Matriz Extracelular , Humanos , Grasa Intraabdominal/citología , Miofibroblastos/citología , Miofibroblastos/efectos de los fármacos , Proteínas del Tejido Nervioso/metabolismo , Obesidad , Receptores de Factor de Crecimiento Nervioso/metabolismo , Células Madre/metabolismo , Grasa Subcutánea/citología , Factor de Crecimiento Transformador beta1/farmacología
11.
Sci Rep ; 9(1): 3279, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30824769

RESUMEN

Superantigens (SAgs) play a major role in the pathogenesis of Staphylococcus aureus and are associated with several diseases, including food poisoning, bacterial arthritis, and toxic shock syndrome. Monoclonal antibodies to these SAgs, primarily TSST-1, SEB and SEA have been shown to provide protection in animal studies and to reduce clinical severity in bacteremic patients. Here we quantify the pre-existing antibodies against SAgs in many human plasma and IVIG samples and demonstrate that in a major portion of the population these antibody titers are suboptimal and IVIG therapy only incrementally elevates the anti-SAg titers. Our in vitro neutralization studies show that a combination of antibodies against SEA, SEB,and TSST-1 can provide broad neutralization of staphylococcal SAgs. We report a single fusion protein (TBA225) consisting of the toxoid versions of TSST-1, SEB and SEA and demonstrate its immunogenicity and protective efficacy in a mouse model of toxic shock. Antibodies raised against this fusion vaccine provide broad neutralization of purified SAgs and culture supernatants of multiple clinically relevant S. aureus strains. Our data strongly supports the use of this fusion protein as a component of an anti-virulence based multivalent toxoid vaccine against S. aureus disease.


Asunto(s)
Enterotoxinas/toxicidad , Proteínas Recombinantes de Fusión/farmacología , Toxoide Estafilocócico/farmacología , Staphylococcus aureus , Superantígenos/toxicidad , Animales , Enterotoxinas/química , Enterotoxinas/genética , Enterotoxinas/inmunología , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Toxoide Estafilocócico/química , Toxoide Estafilocócico/genética , Toxoide Estafilocócico/inmunología , Staphylococcus aureus/química , Staphylococcus aureus/genética , Staphylococcus aureus/inmunología , Superantígenos/química , Superantígenos/genética , Superantígenos/inmunología
12.
PeerJ ; 6: e6055, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30631642

RESUMEN

Successful dispersal of freshwater sponges depends on the formation of dormant sponge bodies (gemmules) under adverse conditions. Gemmule formation allows the sponge to overcome critical environmental conditions, for example, desiccation or freezing, and to re-establish as a fully developed sponge when conditions are more favorable. A key process in sponge development from hatched gemmules is the construction of the silica skeleton. Silica spicules form the structural support for the three-dimensional filtration system the sponge uses to filter food particles from ambient water. We studied the effect of different hypergravity forces (1, 2.5, 5, 10, and 20 × g for 48 h)-as measure for environmental stress-on the ability of developing sponges to set-up their spiculous skeleton. Additionally, we assessed whether the addition of nutrients (i.e., dissolved 13C- and 15N-labeled amino acids) compensates for this stress. Our results show that freshwater sponges can withstand prolonged periods of hypergravity exposure and successfully set-up their skeleton, even after 48 h under 20 × g. Developing sponges were found to take up and assimilate dissolved food before forming a functional filtering system. However, fed and non-fed sponges showed no differences in skeleton formation and relative surface area growth, suggesting that the gemmules' intrinsic energy fulfills the processes of skeleton construction. Additionally, non-fed sponges formed oscula significantly more often than fed sponges, especially under higher g-forces. This suggests that the eventual formation of a filtration system might be stimulated by food deprivation and environmentally stressful conditions. These findings indicate that the process of spiculous skeleton formation is energy-efficient and highly resilient. The uptake of dissolved food substances by freshwater sponges may contribute to the cycling of dissolved organic matter in freshwater ecosystems where sponges are abundant.

13.
Rev Mal Respir ; 36(2): 209-213, 2019 Feb.
Artículo en Francés | MEDLINE | ID: mdl-30686563

RESUMEN

Anti-PD1 immunotherapies have become an essential treatment for bronchial cancer. According to published studies, PD1 and PD-L1 inhibitors have a better toxicity profile than chemotherapy. Nevertheless, some immune related toxicities can be potentially severe, such as induced interstitial lung disease (ILD). Currently, ILD patients are excluded from clinical trials using immunotherapy in lung cancer. IPF is the most frequent and severe form of ILD. Lung cancer represents a major complication of this disease and to date few data exist on the safety of immunotherapy in this context. We report 3 cases of IPF with lung cancer treated by nivolumab. All had a clinically mild to moderate IPF. The patients had received at least one line of chemotherapy before nivolumab and had progressive, metastatic lung cancer. Two patients experienced rapid cancer progression without immune toxicities. The third had a partial response but developed grade III immune colitis that led to discontinuation of the treatment. None developed lung toxicity or worsening of IPF on CT during follow-up, and death was always related to progression of the cancer. In our series of three patients with IPF, nivolumab was well tolerated with regard to their pulmonary condition. As inflammation and autoimmunity are probably marginal mechanisms in the pathogenesis of IPF, we do not believe that the presence of IPF should definitely disqualify potential candidates for treatment with nivolumab. Decisions should be taken, case-by-case, in selected patients without severe IPF and with no evidence of autoimmunity. In view of the epidemiology of lung cancer in IPF and the critical role of immunotherapy in the management of lung cancer, studies of prospective cohorts are urgently needed in this population.


Asunto(s)
Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Inmunoterapia/efectos adversos , Nivolumab/uso terapéutico , Adenocarcinoma del Pulmón/complicaciones , Adenocarcinoma del Pulmón/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/complicaciones , Carcinoma de Células Escamosas/tratamiento farmacológico , Colitis/inducido químicamente , Colitis/diagnóstico , Colitis/inmunología , Comorbilidad , Progresión de la Enfermedad , Humanos , Fibrosis Pulmonar Idiopática/complicaciones , Fibrosis Pulmonar Idiopática/patología , Inmunoterapia/métodos , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Masculino , Nivolumab/efectos adversos
15.
Nat Commun ; 9(1): 5287, 2018 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-30538243

RESUMEN

Neurons communicate through electrochemical signaling within a complex network. These signals are composed of changes in membrane potentials and are traditionally measured with the aid of (toxic) fluorescent labels or invasive electrical probes. Here, we demonstrate an improvement in label-free second harmonic neuroimaging sensitivity by ~3 orders of magnitude using a wide-field medium repetition rate illumination. We perform a side-by-side patch-clamp and second harmonic imaging comparison to demonstrate the theoretically predicted linear correlation between whole neuron membrane potential changes and the square root of the second harmonic intensity. We assign the ion induced changes to the second harmonic intensity to changes in the orientation of membrane interfacial water, which is used to image spatiotemporal changes in the membrane potential and K+ ion flux. We observe a non-uniform spatial distribution and temporal activity of ion channels in mouse brain neurons.


Asunto(s)
Membrana Celular/metabolismo , Neuronas/química , Agua/metabolismo , Animales , Membrana Celular/química , Iones/análisis , Iones/metabolismo , Cinética , Potenciales de la Membrana , Ratones , Neuronas/citología , Neuronas/metabolismo , Técnicas de Placa-Clamp , Análisis de la Célula Individual , Agua/química
16.
PeerJ ; 6: e5966, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30533295

RESUMEN

Anthropogenic pressures threaten the health of coral reefs globally. Some of these pressures directly affect coral functioning, while others are indirect, for example by promoting the capacity of bioeroders to dissolve coral aragonite. To assess the coral reef status, it is necessary to validate community-scale measurements of metabolic and geochemical processes in the field, by determining fluxes from enclosed coral reef patches. Here, we investigate diurnal trends of carbonate chemistry, dissolved organic carbon, oxygen, and nutrients on a 20 m deep coral reef patch offshore from the island of Saba, Dutch Caribbean by means of tent incubations. The obtained trends are related to benthic carbon fluxes by quantifying net community calcification (NCC) and net community production (NCP). The relatively strong currents and swell-induced near-bottom surge at this location caused minor seawater exchange between the incubated reef and ambient water. Employing a compensating interpretive model, the exchange is used to our advantage as it maintains reasonably ventilated conditions, which conceivably prevents metabolic arrest during incubation periods of multiple hours. No diurnal trends in carbonate chemistry were detected and all net diurnal rates of production were strongly skewed towards respiration suggesting net heterotrophy in all incubations. The NCC inferred from our incubations ranges from -0.2 to 1.4 mmol CaCO3 m-2 h-1 (-0.2 to 1.2 kg CaCO3 m-2 year-1) and NCP varies from -9 to -21.7 mmol m-2 h-1 (net respiration). When comparing to the consensus-based ReefBudget approach, the estimated NCC rate for the incubated full planar area (0.36 kg CaCO3 m-2 year-1) was lower, but still within range of the different NCC inferred from our incubations. Field trials indicate that the tent-based incubation as presented here, coupled with an appropriate interpretive model, is an effective tool to investigate, in situ, the state of coral reef patches even when located in a relatively hydrodynamic environment.

17.
Rev Mal Respir ; 35(7): 745-748, 2018 Sep.
Artículo en Francés | MEDLINE | ID: mdl-30098879

RESUMEN

INTRODUCTION: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure designed to explore mediastinal lymphadenopathy. Its use and indications have increased recently and severe, though rare, complications have been reported. CASE REPORT: EBUS-TBNA was performed in a 64-year-old patient presenting with mediastinal lymphadenopathy, probably due to sarcoidosis, but without histological proof. Within hours of the aspiration of subcarinal lymph nodes (station 7), the patient developed fever and dry cough associated with progressive dysphagia and dysphonia that persisted for four weeks. Mediastinitis was diagnosed after a CT-scan revealed a collection in the subcarinal space previously tapped using CT guidance. Intravenous antibiotics were started and both symptoms and the mediastinal collection resolved without need of a surgical procedure. The patient recovered fully. CONCLUSION: EBUS-TBNA is associated with a risk of mediastinitis that may manifest as an isolated fever arising within hours of the procedure. The pathogens responsible are usually contaminants from the oropharynx such as Streptococcus sp, probably inoculated directly into the mediastinum during transbronchial needle aspiration. Rapid diagnosis and treatment are necessary in order to reduce morbidity and mortality associated with mediastinitis.


Asunto(s)
Broncoscopía/efectos adversos , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/efectos adversos , Mediastinitis/etiología , Complicaciones Posoperatorias/patología , Broncoscopía/métodos , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/métodos , Humanos , Linfadenopatía , Masculino , Mediastinitis/patología , Persona de Mediana Edad , Sarcoidosis Pulmonar/patología , Sarcoidosis Pulmonar/cirugía
18.
Nature ; 560(7716): 76-79, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29988081

RESUMEN

The past two million years of eastern African climate variability is currently poorly constrained, despite interest in understanding its assumed role in early human evolution1-4. Rare palaeoclimate records from northeastern Africa suggest progressively drier conditions2,5 or a stable hydroclimate6. By contrast, records from Lake Malawi in tropical southeastern Africa reveal a trend of a progressively wetter climate over the past 1.3 million years7,8. The climatic forcings that controlled these past hydrological changes are also a matter of debate. Some studies suggest a dominant local insolation forcing on hydrological changes9-11, whereas others infer a potential influence of sea surface temperature changes in the Indian Ocean8,12,13. Here we show that the hydroclimate in southeastern Africa (20-25° S) is controlled by interplay between low-latitude insolation forcing (precession and eccentricity) and changes in ice volume at high latitudes. Our results are based on a multiple-proxy reconstruction of hydrological changes in the Limpopo River catchment, combined with a reconstruction of sea surface temperature in the southwestern Indian Ocean for the past 2.14 million years. We find a long-term aridification in the Limpopo catchment between around 1 and 0.6 million years ago, opposite to the hydroclimatic evolution suggested by records from Lake Malawi. Our results, together with evidence of wetting at Lake Malawi, imply that the rainbelt contracted toward the Equator in response to increased ice volume at high latitudes. By reducing the extent of woodland or wetlands in terrestrial ecosystems, the observed changes in the hydroclimate of southeastern Africa-both in terms of its long-term state and marked precessional variability-could have had a role in the evolution of early hominins, particularly in the extinction of Paranthropus robustus.


Asunto(s)
Evolución Biológica , Clima , Hominidae , Lluvia , Alcanos/análisis , Alcanos/química , Animales , Extinción Biológica , Foraminíferos/química , Bosques , Historia Antigua , Hidrología , Océano Índico , Lagos , Malaui , Plantas/química , Ríos , Ciclo Hidrológico , Ceras/química , Humedales
19.
PLoS One ; 13(5): e0197824, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29847572

RESUMEN

Excavating sponges are among the most important macro-eroders of carbonate substrates in marine systems. Their capacity to remove substantial amounts of limestone makes these animals significant players that can unbalance the reef carbonate budget of tropical coral reefs. Nevertheless, excavating sponges are currently rarely incorporated in standardized surveys and experimental work is often restricted to a few species. Here were provide chemical and mechanical bioerosion rates for the six excavating sponge species most commonly found on the shallow reef of Curaçao (southern Caribbean): Cliona caribbaea, C. aprica, C. delitrix, C. amplicavata, Siphonodictyon brevitubulatum and Suberea flavolivescens. Chemical, mechanical and total bioerosion rates were estimated based on various experimental approaches applied to sponge infested limestone cores. Conventional standing incubation techniques were shown to strongly influence the chemical dissolution signal. Final rates, based on the change in alkalinity of the incubation water, declined significantly as a function of incubation time. This effect was mitigated by the use of a flow-through incubation system. Additionally, we found that mechanically removed carbonate fragments collected in the flow-through chamber (1 h) as well as a long-term collection method (1 wk) generally yielded comparable estimates for the capacity of these sponges to mechanically remove substratum. Observed interspecific variation could evidently be linked to the adopted boring strategy (i.e. gallery-forming, cavity-forming or network-working) and presence or absence of symbiotic zooxanthellae. Notably, a clear diurnal pattern was found only in species that harbour a dense photosymbiotic community. In these species chemical erosion was substantially higher during the day. Overall, the sum of individually acquired chemical and mechanical erosion using flow-through incubations was comparable to rates obtained gravimetrically. Such consistency is a first in this field of research. These findings support the much needed confirmation that, depending on the scientific demand, the different approaches presented here can be implemented concurrently as standardized methods.


Asunto(s)
Arrecifes de Coral , Fenómenos Mecánicos , Poríferos/química , Animales , Curazao , Simbiosis
20.
Mar Genomics ; 37: 135-147, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29198427

RESUMEN

Regeneration is an essential process for all multicellular organisms, allowing them to recover effectively from internal and external injury. This process has been studied extensively in a medical context in vertebrates, with pathways often investigated mechanistically, both to derive increased understanding and as potential drug targets for therapy. Several species from other parts of the metazoan tree of life, including Hydra, planarians and echinoderms, noted for their regenerative capabilities, have previously been targeted for study. Less well-documented for their regenerative abilities are sponges. This is surprising, as they are both one of the earliest-branching extant metazoan phyla on Earth, and are rapidly able to respond to injury. Their sessile lifestyle, lack of an external protective layer, inability to respond to predation and filter-feeding strategy all mean that regeneration is often required. In particular the demosponge genus Halisarca has been noted for its fast cell turnover and ability to quickly adjust its cell kinetic properties to repair damage through regeneration. However, while the rate and structure of regeneration in sponges has begun to be investigated, the molecular mechanisms behind this ability are yet to be catalogued. Here we describe the assembly of a reference transcriptome for Halisarca caerulea, along with additional transcriptomes noting response to injury before, shortly following (2h post-), and 12h after trauma. RNAseq reads were assembled using Trinity, annotated, and samples compared, to allow initial insight into the transcriptomic basis of sponge regenerative processes. These resources are deep, with our reference assembly containing >92.6% of the BUSCO Metazoa set of genes, and well-assembled (N50s of 836, 957, 1688 and 2032 for untreated, 2h, 12h and reference transcriptomes respectively), and therefore represent excellent qualitative resources as a bedrock for future study. The generation of transcriptomic resources from sponges before and following deliberate damage has allowed us to study particular pathways within this species responsible for repairing damage. We note particularly the involvement of the Wnt cascades in this process in this species, and detail the contents of this cascade, along with cell cycle, extracellular matrix and apoptosis-linked genes in this work. This resource represents an initial starting point for the continued development of this knowledge, given H. caerulea's ability to regenerate and position as an outgroup for comparing the process of regeneration across metazoan lineages. With this resource in place, we can begin to infer the regenerative capacity of the common ancestor of all extant animal life, and unravel the elements of regeneration in an often-overlooked clade.


Asunto(s)
Evolución Molecular , Poríferos/fisiología , Regeneración/genética , Transcriptoma , Animales , Poríferos/genética , Factores de Tiempo
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