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1.
Obes Surg ; 34(8): 2766-2777, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39023675

RESUMEN

INTRODUCTION: Intragastric balloon (IGB) is a minimally invasive and reversible option for obesity treatment. There is a worldwide growing number of different IGB models. The efficacy and safety profile for each model must be demonstrated. We aim to evaluate IGB safety profile according to the experience of the Spanish Bariatric Endoscopy Group (GETTEMO). METHODS: A survey of 37 IGBs safety-related questions was sent to all GETTEMO members, to retrospectively collect a multicenter Spanish registry. Incidence, causes, and resolution of both major and minor complications and adverse events (AEs), including legal consequences, differentiated for each balloon model were evaluated. Secondary outcome was weight loss data to confirm efficacy. RESULTS: Twenty-one Spanish hospitals experienced in IGBs responded. The overall data encompassed 20,680 IGBs, including 12 different models. Mean %TBWL of 17.66 ± 2.5% was observed. Early removal rate due to intolerance was 3.62%. Mean major complications rate was 0.70% (> 1% in Spatz2, HB, and Spatz3 models), mainly complicated gastric ulcer. Minor AEs rate was 6.37%, mainly esophagitis. Nine cases (0.04%) required surgery. A single case of mortality (0.0048%) occurred. Seven lawsuits (0.0034%) were received, all with favorable resolution. CONCLUSIONS: In the Spanish experience accumulating 20,680 IGBs and including 12 different balloon models, a low incidence rate of major complications and minor AEs are observed (0.70% and 6.37%, respectively), mostly resolved with medical/endoscopic management. IGB shows good tolerance and efficacy profile. These safety data are within the accepted quality standards.


Asunto(s)
Balón Gástrico , Obesidad Mórbida , Pérdida de Peso , Humanos , España/epidemiología , Estudios Retrospectivos , Femenino , Obesidad Mórbida/cirugía , Masculino , Adulto , Persona de Mediana Edad , Resultado del Tratamiento , Complicaciones Posoperatorias/epidemiología , Sistema de Registros
2.
Sci Adv ; 10(21): eadj1539, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38781331

RESUMEN

Microbial associations and interactions drive and regulate nutrient fluxes in the ocean. However, physical contact between cells of marine cyanobacteria has not been studied thus far. Here, we show a mechanism of direct interaction between the marine cyanobacteria Prochlorococcus and Synechococcus, the intercellular membrane nanotubes. We present evidence of inter- and intra-genus exchange of cytoplasmic material between neighboring and distant cells of cyanobacteria mediated by nanotubes. We visualized and measured these structures in xenic and axenic cultures and in natural samples. We show that nanotubes are produced between living cells, suggesting that this is a relevant system of exchange material in vivo. The discovery of nanotubes acting as exchange bridges in the most abundant photosynthetic organisms in the ocean may have important implications for their interactions with other organisms and their population dynamics.


Asunto(s)
Nanotubos , Prochlorococcus , Synechococcus , Synechococcus/metabolismo , Nanotubos/química , Prochlorococcus/metabolismo , Cianobacterias/metabolismo , Organismos Acuáticos , Agua de Mar/microbiología
3.
Curr Opin Microbiol ; 78: 102432, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38325247

RESUMEN

Cyanobacteria evolved the oxygenic photosynthesis to generate organic matter from CO2 and sunlight, and they were responsible for the production of oxygen in the Earth's atmosphere. This made them a model for photosynthetic organisms, since they are easier to study than higher plants. Early studies suggested that only a minority among cyanobacteria might assimilate organic compounds, being considered mostly autotrophic for decades. However, compelling evidence from marine and freshwater cyanobacteria, including toxic strains, in the laboratory and in the field, has been obtained in the last decades: by using physiological and omics approaches, mixotrophy has been found to be a more widespread feature than initially believed. Furthermore, dominant clades of marine cyanobacteria can take up organic compounds, and mixotrophy is critical for their survival in deep waters with very low light. Hence, mixotrophy seems to be an essential trait in the metabolism of most cyanobacteria, which can be exploited for biotechnological purposes.


Asunto(s)
Cianobacterias , Cianobacterias/genética , Cianobacterias/metabolismo , Fotosíntesis/fisiología , Atmósfera , Oxígeno/metabolismo
4.
Rev Esp Enferm Dig ; 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38205701

RESUMEN

Endoscopic retrograde cholangio-pancreatography (ERCP) is a diagnostic, therapeutic technique for the management of pancreato-biliary conditions. Technical contraindications include the presence of intraluminal foreign bodies precluding endoscope passage. Intragastric balloon (IGB) is a bariatric procedure that provides sensations of early fullness and satiety from intragastric occupation, thus leading to weight loss. While, according to guidelines, choledocholithiasis and cholangitis do not represent an indication for IGB removal in contrast to moderate-severe pancreatitis, where need for an ERCP and the procedure's technical difficulty most commonly require it. We report the case of a female patient with an IGB where ERCP was indicated. CASE REPORT: A 47-year-old woman visited the emergency room for epigastric abdominal pain radiating to her back. She had jaundice without pyrexic symptoms. At the ER an ultrasonogram revealed cholelithiasis and a dilated common bile duct (11 mm in diameter), no cause being then identified. Lab tests rule out pancreatic involvement and associated infection. The patient had an IGB (Photo 1a) implanted 5 months before the present episode. She was admitted to the gastroenterology ward with choledocholithiasis as suspected diagnosis. The study was completed by endoscopic ultrasound (EUS), which confirmed a dilated hepatocholedochal duct at 15.3 mm in diameter (Photo 1b), secondary to multiple choledochal stones. A direct ERCP procedure was initiated where the IGB precluded rectification and proper placement, which forced the use of a double-guidewire technique for cannulation (Photo 1c)5. Sphincterotomy and sphincteroplasty to 10 mm ensued, and 8 stones were removed using a balloon and then a basket catheter (Photo 1d). The patient was discharged at 24 hours after the procedure with no complications. DISCUSSION: No prior studies are available that describe the possibility of therapeutic ERCP for choledocholithiasis in IGB-carrying patients; in most cases IGB removal is taken for granted because of the procedure's technical difficulty. Our case report may well show a safe alternative to IGB removal by using less conventional cannulation techniques without higher complication rates. However, further cases are needed in order to draw significant conclusions regarding their widespread use.

5.
Rev Esp Enferm Dig ; 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38235668

RESUMEN

Dieulafoy's lesion (DL) is an uncommon vascular malformation-an aberrant, dilated submucosal arteriole (1-3 mm thick, 10 x nv). It runs near the mucosal surface and protrudes, and may potentially induce gastrointestinal bleeding (GIB). It usually originates in the stomach (upper lesser curvature), with endoscopy being the diagnostic, therapeutic modality of choice. Jejunal DL (JDL) is a rare cause of obscure GIB (OGIB) that is challenging for endoscopists and threatens patient lives. Other diagnostic techniques such as Tc99m-labeled red blood cell scintigraphy, well established in the classic armamentarium for OGIB diagnosis, cannot overcome endoscopic procedures. We report the case of a patient with OGIB secondary to an exceptionally located Dieulafoy's lesion who underwent combined endoscopic treatment.

6.
J Clin Monit Comput ; 38(1): 37-45, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37540323

RESUMEN

The laryngeal mask airway (LMA) is commonly used for airway management. Cuff hyperinflation has been associated with complications, poor ventilation and increased risk of gastric insufflation. This study was designed to determine the best cuff inflation method of AuraOnce™ LMA during bronchoscopy and EBUS (Endobronquial Ultrasound Bronchoscopy) procedure. We designed a Randomized controlled, doble-blind, clinical trial to compare the efficacy and safety of three cuff inflation methods of AuraOnce™ LMA. 210 consenting patients scheduled for EBUS procedure under general anesthesia, using AuraOnce™ LMA were randomized into three groups depending on cuff insufflation: residual volume (RV), half of the maximum volume (MV), unchanged volume (NV). Parameters regarding intracuff pressure (IP), airway leak pressure (OLP), leakage volume (LV) were assessed, as well as postoperative complications (PC). 201 (95.7%) patients completed the study. Mean IP differed between groups (MV: 59.4 ± 32.4 cm H2O; RV: 75.1 ± 21.1 cm H2O; NV: 83.1 ± 25.5 cmH20; P < 0.01). The incidence of IP > 60 cmH2O was lower in the MV group compared to the other two (MV: 20/65(30.8%); RV:47/69 (68.1%); NV 48/67 (71.6%); p < 0.01). The insertion success rate was 89,6% (180/201) at first attempt, with no difference between groups (p = 0.38). No difference between groups was found either for OLP (p = 0.53), LV (p = 0.26) and PC (p = 0.16). When a cuff manometer is not available, a partial inflation of AuraOnce™ LMA cuff using MV method allows to control intracuff pressure, with no significant changes of OLP and LV compared to RV and NV insufflation method.Registration clinical trial: NCT04769791.


Asunto(s)
Insuflación , Máscaras Laríngeas , Humanos , Máscaras Laríngeas/efectos adversos , Insuflación/efectos adversos , Anestesia General/métodos , Complicaciones Posoperatorias/etiología , Manejo de la Vía Aérea/efectos adversos
7.
Environ Int ; 183: 108252, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38157608

RESUMEN

Understanding the atmospheric processes involving carbonaceous aerosols (CAs) is crucial for assessing air pollution impacts on human health and climate. The sources and formation mechanisms of CAs are not well understood, making it challenging to quantify impacts in models. Studies suggest residential wood combustion (RWC) and traffic significantly contribute to CAs in Europe's urban and rural areas. Here, we used an atmospheric chemistry model (MONARCH) and three different emission inventories (two versions of the European-scale emission inventory CAMS-REG_v4 and the HERMESv3 detailed national inventory for Spain) to assess the uncertainties in CAs simulation and source allocation (from traffic, RWC, shipping, fires and others) in Northeast Spain. For this, black carbon (BC) and organic aerosol (OA) measurements performed at three supersites representing different environments (urban, regional and remote) were used. Our findings show the importance of model resolution and detailed emission input data in accurately reproducing BC/OA observations. Even though emissions of total particulate matter are rather consistent between inventories in Spain, we found discrepancies between them mainly related to the spatiotemporal disaggregation (particularly relevant for traffic and RWC) and the treatment of the condensable fraction of CAs in RWC (changes in the speciation of elemental/organic carbon). The main source contribution to BC concentrations in the urban site is traffic, accounting for 71.1%/65.2% (January/July) in close agreement with the fossil contribution derived from observations (78.8%/84.2%), followed by RWC (12.8%/3%) and shipping emissions (5.4%/13.8%). An over-representation of RWC (winter) and shipping (summer) is obtained with CAMS-REG_v4. Noteworthy uncertainties arise in OA results due to condensables in emissions and a limited secondary aerosol production in the model. These findings offer insights into MONARCH's effectiveness in simulating CAs concentrations and source contribution in Northeast Spain. The study highlights the benefits of combining new datasets and modeling techniques to refine emission inventories and better understand and mitigate air pollution impacts.


Asunto(s)
Contaminantes Atmosféricos , Humanos , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Carbono/análisis , Aerosoles/análisis , Región Mediterránea
8.
Rev Esp Enferm Dig ; 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37882160

RESUMEN

Obesity represents a significant global health problem, and reducing its alarmingly high incidence is an urgent challenge. The intragastric balloon is a safe and effective device for weight loss; therefore, it is widely used. Although the frequency of serious complications resulting from its use is low, it is not exempt from them. We would like to present a case of a severe but infrequent complication secondary to this device, with the aim of highlighting the most appropriate procedure in such cases and emphasizing the importance of awareness regarding it.

9.
Sci Total Environ ; 902: 166440, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37611714

RESUMEN

Organic aerosols (OA) have recently been shown to be the dominant contributor to the oxidative potential of airborne particulate matter in northeastern Spain. We collected PM10 filter samples every fourth day from January 2017 to March 2018 at two sampling stations located in Barcelona city and Montseny Natural Park, representing urban and rural areas, respectively. The chemical composition of PM10 was analyzed offline using a broad set of analytical instruments, including high-resolution time-of-flight mass spectrometry (HR-ToF-AMS), a total organic carbon analyzer (TCA), inductively coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS), ion chromatography (IC), and thermal-optical carbon analyzer. Source apportionment analysis of the water-soluble organic content of the samples measured via HR-ToF-AMS revealed two primary and two secondary sources of OA, which included biomass-burning OA (BBOA), sulfur-containing OA (SCOA), as well as summer- and winter­oxygenated OA (SOOA and WOOA). The presence of hydrocarbon-like water-insoluble OA was also identified based on concentration trends in black carbon and nitrogen oxides. The results from the source apportionment analysis of the inorganic composition were correlated with different OA factors to assess potential source contributors. Barcelona showed significantly higher average water-soluble OA concentrations (5.63 ± 0.56 µg m-3) than Montseny (3.27 ± 0.37 µg m-3) over the sampling period. WOOA accounted for nearly 27 % of the averaged OA in Barcelona compared to only 7 % in Montseny. In contrast, SOOA had a greater contribution to OA in Montseny (47 %) than in Barcelona (24 %). SCOA and BBOA were responsible for 15-28 % of the OA at both sites. There were also seasonal variations in the relative contributions of different OA sources. Our overall results showed that local anthropogenic sources were primarily responsible for up to 70 % of ambient soluble OA in Barcelona, and regulating local-scale emissions could significantly improve air quality in urban Spain.

10.
Environ Int ; 177: 108006, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37285710

RESUMEN

Source apportionment (SA) techniques allocate the measured ambient pollutants with their potential source origin; thus, they are a powerful tool for designing air pollution mitigation strategies. Positive Matrix Factorization (PMF) is one of the most widely used SA approaches, and its multi-time resolution (MTR) methodology, which enables mixing different instrument data in their original time resolution, was the focus of this study. One year of co-located measurements in Barcelona, Spain, of non-refractory submicronic particulate matter (NR-PM1), black carbon (BC) and metals were obtained by a Q-ACSM (Aerodyne Research Inc.), an aethalometer (Aerosol d.o.o.) and fine offline quartz-fibre filters, respectively. These data were combined in a MTR PMF analysis preserving the high time resolution (30 min for the NR-PM1 and BC, and 24 h every 4th day for the offline samples). The MTR-PMF outcomes were assessed varying the time resolution of the high-resolution data subset and exploring the error weightings of both subsets. The time resolution assessment revealed that averaging the high-resolution data was disadvantageous in terms of model residuals and environmental interpretability. The MTR-PMF resolved eight PM1 sources: ammonium sulphate + heavy oil combustion (25%), ammonium nitrate + ammonium chloride (17%), aged secondary organic aerosol (SOA) (16%), traffic (14%), biomass burning (9%), fresh SOA (8%), cooking-like organic aerosol (5%), and industry (4%). The MTR-PMF technique identified two more sources relative to the 24 h base case data subset using the same species and four more with respect to the pseudo-conventional approach mimicking offline PMF, indicating that the combination of both high and low TR data is significantly beneficial for SA. Besides the higher number of sources, the MTR-PMF technique has enabled some sources disentanglement compared to the pseudo-conventional and base case PMF as well as the characterisation of their intra-day patterns.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Contaminación del Aire/análisis , Aerosoles/análisis
11.
Rev Esp Enferm Dig ; 115(6): 347-348, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37204097

RESUMEN

Endoscopic retrograde cholangiopancreatography (ERCP) is one of the most frequently performed procedures in the treatment of biliary-pancreatic diseases. Hematoma after ERCP is an infrequent and highly serious complication. We present three cases with hepatic hematoma after a CPRE.


Asunto(s)
Sistema Biliar , Enfermedades de la Vesícula Biliar , Hepatopatías , Enfermedades Pancreáticas , Humanos , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Hepatopatías/etiología , Enfermedades Pancreáticas/complicaciones , Hematoma/diagnóstico por imagen , Hematoma/etiología
12.
Rev Esp Enferm Dig ; 115(8): 471-472, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36975147

RESUMEN

Colonic lymphoma involving the mucosa-associated lymphoid tissue (MALT) is an uncommon pathology, with an unknown pathogenesis and varied endoscopic appearance. We present the case of a 78-year-old female with challenging endoscopic findings that resulted in the diagnosis of a colonic MALT lymphoma.


Asunto(s)
Neoplasias del Colon , Linfoma de Células B de la Zona Marginal , Femenino , Humanos , Anciano , Linfoma de Células B de la Zona Marginal/diagnóstico por imagen , Linfoma de Células B de la Zona Marginal/cirugía , Endoscopía , Neoplasias del Colon/diagnóstico por imagen , Neoplasias del Colon/cirugía , Neoplasias del Colon/patología
13.
Microbiol Spectr ; : e0327522, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36722960

RESUMEN

We compared changes induced by the addition of 100 nM and 5 mM glucose on the proteome and metabolome complements in Synechococcus sp. strains WH8102, WH7803, and BL107 and Prochlorococcus sp. strains MED4, SS120, and MIT9313, grown either under standard light conditions or in darkness. Our results suggested that glucose is metabolized by these cyanobacteria, using primarily the oxidative pentoses and Calvin pathways, while no proof was found for the involvement of the Entner-Doudoroff pathway in this process. We observed differences in the effects of glucose availability, both between genera and between Prochlorococcus MED4 and SS120 strains, which might be related to their specific adaptations to the environment. We found evidence for fermentation in Prochlorococcus sp. strain SS120 and Synechococcus sp. strain WH8102 after 5 mM glucose addition. Our results additionally suggested that marine cyanobacteria can detect nanomolar glucose concentrations in the environment and that glucose might be used to sustain metabolism under darkness. Furthermore, the KaiB and KaiC proteins were also affected in Synechococcus sp. WH8102, pointing to a direct link between glucose assimilation and circadian rhythms in marine cyanobacteria. In conclusion, our study provides a wide overview on the metabolic effects induced by glucose availability in representative strains of the diverse marine picocyanobacteria, providing further evidence for the importance of mixotrophy in marine picocyanobacteria. IMPORTANCE Glucose uptake by marine picocyanobacteria has been previously described and strongly suggests they are mixotrophic organisms (capable of using energy from the sun to make organic matter, but also to directly use organic matter from the environment when available). However, a detailed analysis of the effects of glucose addition on the proteome and metabolome of these microorganisms had not been carried out. Here, we analyzed three Prochlorococcus sp. and three Synechococcus sp. strains which were representative of several marine picocyanobacterial clades. We observed differential features in the effects of glucose availability, depending on both the genus and strain; our study illuminated the strategies utilized by these organisms to metabolize glucose and showed unexpected links to other pathways, such as circadian regulation. Furthermore, we found glucose addition had profound effects in the microbiome, favoring the growth of coexisting heterotrophic bacteria.

14.
Rev Esp Enferm Dig ; 115(1): 22-34, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36426855

RESUMEN

BACKGROUND: intragastric balloons (IGBs) are a minimally invasive, increasingly popular option for obesity treatment. However, there is only one worldwide guideline standardizing the technical aspects of the procedure (BIBC, SOARD 2018). OBJECTIVES: to construct a practical guideline for IGB usage by reproducing and expanding the BIBC survey among the Spanish Bariatric Endoscopy Group (GETTEMO). METHODS: a 140-question survey was submitted to all GETTEMO members. Twenty-one Spanish experienced endoscopists in IGBs answered back. Eight topics on patient selection, indications/contraindications, technique, multidisciplinary follow-up, results, safety, and financial/legal aspects were discussed. Consensus was defined as consensus ≥ 70 %. RESULTS: overall data included 20 680 IGBs including 12 different models. Mean age was 42.0 years-old, 79.9 % were women, and the mean preoperative body mass index (BMI) was 34.05 kg/m². Indication in BMI > 25 kg/m², 10 absolute contraindications, and nutritional and medication measures at follow-up were settled. A mean %TBWL (total body weight loss) of 17.66 % ± 2.5 % was observed. Early removal rate due to intolerance was 3.62 %. Adverse event rate was 0.70 % and 6.37 % for major and minor complications with consensual management. A single case of mortality occurred. IGBs were placed in private health, prior contract, and with full and single payment at the beginning. Seven lawsuits (0.034 %) were received, all ran through civil proceeding, and with favorable final resolution. CONCLUSIONS: this consensus based on more than 20 000 cases represents practical recommendations to perform IGB procedures. This experience shows that the device leads to satisfactory weight loss with a low rate of adverse events. Most results are reproducible compared to those obtained by the BIBC.


Asunto(s)
Balón Gástrico , Obesidad Mórbida , Humanos , Femenino , Adulto , Masculino , Balón Gástrico/efectos adversos , Endoscopía Gastrointestinal , Consenso , Pérdida de Peso , Índice de Masa Corporal , Obesidad Mórbida/cirugía , Resultado del Tratamiento
15.
Biochim Biophys Acta Bioenerg ; 1864(2): 148954, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36563737

RESUMEN

The marine cyanobacterium Prochlorococcus is one of the main primary producers on Earth, which can take up glucose by using the high affinity, multiphasic transporter GlcH. We report here the overexpression of glcH from Prochlorococcus marinus strain SS120 in Escherichia coli. Modeling studies of GlcH using the homologous MelB melibiose transporter from Salmonella enterica serovar Typhimurium showed high conservation at the overall fold. We observed that an important structural interaction, mediated by a strong hydrogen bond between D8 and R141, is conserved in Prochlorococcus, although the corresponding amino acids in MelB from Salmonella are different. Biased docking studies suggested that when glucose reaches the pocket of the transporter and interacts with D8 and R141, the hydrogen bond network in which these residues are involved could be disrupted, favoring a conformational change with the subsequent translocation of the glucose molecule towards the cytoplasmic region of the pmGlcH structure. Based on these theoretical predictions and on the conservation of N117 and W348 in other MelB structures, D8, N117, R141 and W348 were mutated to glycine residues. Their key role in glucose transport was evaluated by glucose uptake assays. N117G and W348G mutations led to 17 % decrease in glucose uptake, while D8G and R141G decreased the glucose transport by 66 % and 92 % respectively. Overall, our studies provide insights into the Prochlorococcus 3D-structure of GlcH, paving the way for further analysis to understand the features which are involved in the high affinity and multiphasic kinetics of this transporter.


Asunto(s)
Proteínas Facilitadoras del Transporte de la Glucosa , Prochlorococcus , Proteínas Facilitadoras del Transporte de la Glucosa/genética , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Prochlorococcus/genética , Prochlorococcus/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Mutagénesis , Escherichia coli/genética , Glucosa/metabolismo
18.
Rev. esp. enferm. dig ; 114(12): 762-763, diciembre 2022. ilus
Artículo en Español | IBECS | ID: ibc-213548

RESUMEN

La linfangiectasia intestinal primaria es un trastorno raro asociado a una enteropatía pierde-proteínas. Las principales manifestaciones son las derivadas de la hipoalbuminemia. Para lograr el diagnóstico se necesita la imagen endoscópica típica de la linfangiectasia intestinal y el aumento de las cifras de alfa-1-antitripsina en las heces de 24 horas. El tratamiento es básicamente dietético. (AU)


Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Hipoalbuminemia , Edema , Linfangiectasia , Endoscopios en Cápsulas , Intestino Delgado
19.
Microbiol Spectr ; 10(5): e0246622, 2022 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-36098532

RESUMEN

The marine cyanobacterium Prochlorococcus can utilize glucose as a source of carbon. However, the relative importance of inorganic and organic carbon assimilation and the timing of glucose assimilation are still poorly understood in these numerically dominant cyanobacteria. Here, we investigated whole microbial community and group-specific primary production and glucose assimilation using incubations with radioisotopes combined with flow cytometry cell sorting. We also studied changes in the microbial community structure in response to glucose enrichments and analyzed the transcription of Prochlorocccus genes involved in carbon metabolism and photosynthesis. Our results showed a diel variation for glucose assimilation in Prochlorococcus, with maximum assimilation at midday and minimum at midnight (~2-fold change), which was different from that of the total microbial community. This suggests that the timing in glucose assimilation in Prochlorococcus is coupled to photosynthetic light reactions producing energy, it being more convenient for Prochlorococcus to show maximum glucose uptake precisely when the rest of microbial populations have their minimum glucose uptake. Many transcriptional responses to glucose enrichment occurred after 12- and 24-h periods, but community composition did not change. High-light Prochlorococcus strains were the most impacted by glucose addition, with transcript-level increases observed for genes in pathways for glucose metabolism, such as the pentose phosphate pathway, the Entner-Doudoroff pathway, glycolysis, respiration, and glucose transport. While Prochlorococcus C assimilation from glucose represented less than 0.1% of the bacterium's photosynthetic C fixation, increased assimilation during the day and glcH gene upregulation upon glucose enrichment indicate an important role of mixotrophic C assimilation by natural populations of Prochlorococcus. IMPORTANCE Several studies have demonstrated that Prochlorococcus, the most abundant photosynthetic organism on Earth, can assimilate organic molecules, such as amino acids, amino sugars, ATP, phosphonates, and dimethylsulfoniopropionate. This autotroph can also assimilate small amounts of glucose, supporting the hypothesis that Prochlorococcus is mixotrophic. Our results show, for the first time, a diel variability in glucose assimilation by natural populations of Prochlorococcus with maximum assimilation during midday. Based on our previous results, this indicates that Prochlorococcus could maximize glucose uptake by using ATP made during the light reactions of photosynthesis. Furthermore, Prochlorococcus showed a different timing of glucose assimilation from the total population, which may offer considerable fitness advantages over competitors "temporal niches." Finally, we observed transcriptional changes in some of the genes involved in carbon metabolism, suggesting that Prochlorococcus can use both pathways previously proposed in cyanobacteria to metabolize glucose.


Asunto(s)
Organofosfonatos , Prochlorococcus , Prochlorococcus/genética , Prochlorococcus/metabolismo , Glucosa/metabolismo , Agua de Mar , Carbono/metabolismo , Aminoácidos/metabolismo , Adenosina Trifosfato/metabolismo , Amino Azúcares/metabolismo
20.
Microbiol Spectr ; 10(4): e0018722, 2022 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-35852322

RESUMEN

Marine Synechococcus, together with Prochlorococcus, contribute to a significant proportion of the primary production on Earth. The spatial distribution of these two groups of marine picocyanobacteria depends on different factors such as nutrient availability and temperature. Some Synechococcus ecotypes thrive in mesotrophic and moderately oligotrophic waters, where they exploit both oxidized and reduced forms of nitrogen. Here, we present a comprehensive study, which includes transcriptomic and proteomic analyses of the response of Synechococcus sp. strain WH7803 to nanomolar concentrations of nitrate, compared to micromolar ammonium or nitrogen starvation. We found that Synechococcus has a specific response to a nanomolar nitrate concentration that differs from the response shown under nitrogen starvation or the presence of standard concentrations of either ammonium or nitrate. This fact suggests that the particular response to the uptake of nanomolar concentrations of nitrate could be an evolutionary advantage for marine Synechococcus against Prochlorococcus in the natural environment. IMPORTANCE Marine Synechococcus are a very abundant group of photosynthetic organisms on our planet. Previous studies have shown blooms of these organisms when nanomolar concentrations of nitrate become available. We have assessed the effect of nanomolar nitrate concentrations by studying the transcriptome and proteome of Synechococcus sp. WH7803, together with some physiological parameters. We found evidence that Synechococcus sp. strain WH7803 does sense and react to nanomolar concentrations of nitrate, suggesting the occurrence of specific adaptive mechanisms to allow their utilization. Thus, very low concentrations of nitrate in the ocean seem to be a significant nitrogen source for marine picocyanobacteria.


Asunto(s)
Compuestos de Amonio , Prochlorococcus , Synechococcus , Nitratos , Nitrógeno , Proteómica , Agua de Mar
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