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1.
Sci Total Environ ; 926: 171858, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38522529

RESUMO

Forest ecosystems worldwide currently face worrying episodes of forest decline, which have boosted weakening and mortality of the trees. In the Mediterranean region, especially in the southeast Iberian Peninsula, Pinus sylvestris forests are severely affected by this phenomenon, and it has been commonly attributed to drought events. Remarkably, the role of root microbiota on pine decline has been overlooked and remains unclear. We therefore used metabarcoding to identify the belowground microbial communities of decline-affected and unaffected pine trees. Taxonomic composition of bacterial and fungal rhizosphere communities, and fungal populations dwelling in root endosphere showed different profiles depending on the health status of the trees. The root endosphere of asymptomatic trees was as strongly dominated by 'Candidatus Phytoplasma pini' as the root of decline-affected pines, accounting for >99 % of the total bacterial sequences in some samples. Notwithstanding, the titer of this phytopathogen was four-fold higher in symptomatic trees than in symptomless ones. Furthermore, the microbiota inhabiting the root endosphere of decline-affected trees assembled into a less complex and more modularized network. Thus, the observed changes in the microbial communities could be a cause or a consequence of forest decline phenomenon. Moreover, 'Ca. Phytoplasma pini' is positively correlated to Pinus sylvestris decline events, either as the primary cause of pine decline or as an opportunistic pathogen exacerbating the process once the tree has been weaken by other factors.


Assuntos
Microbiota , Pinus sylvestris , Pinus , Mudança Climática , Florestas , Árvores
2.
Biodivers Data J ; 12: e113943, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444837

RESUMO

Background: Dataset of annual monitoring of herbivory effects on the conservation status of the endangered species Androcymbiumeuropaeum (Lange) K. Richt and its associated plant communities is presented in this manuscript. This dataset encompasses the annual monitoring of herbivory effects on the conservation status of the endangered species Androcymbiumeuropaeum. Since 2010, the SERPAM Department (Service of Evaluation, Restoration and Protection of Mediterranean Agrosystems) at the Zaidin Experimental Station, belonging to the Spanish National Research Council (CSIC-EEZ), has conducted annual sampling to assess the impact of both domestic and wild livestock, specifically rabbits, on the pastures where A.europaeum lives. The study consisted of a randomised block design, implementing three distinct treatments to evaluate different management strategies: (1) rabbit and domestic herbivory, (2) exclusion of domestic livestock and (3) exclusion of rabbits and domestic livestock. Within each treatment, two types of monitoring were conducted. Firstly, the abundance of A.europaeum was estimated by counting individuals within 50 cm x 50 cm quadrats. Secondly, plant species diversity was assessed along 2-m long transects using the modified Point-Quadrat method. The research was conducted within the Cabo de Gata-Níjar Natural Park in southern Spain, specifically in the Amoladeras Nature Reserve in Almería. New information: The dataset contains information spanning from 2010 to 2023, providing valuable insights into the annual monitoring of herbivory effects on the conservation status of A.europaeum, contributing to our understanding of the species' interaction with domestic and wild animal in the studied area.

4.
Inorg Chem ; 62(45): 18496-18509, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37910080

RESUMO

The useful concepts of reticular chemistry, rigid and predictable metal nodes together with strong and manageable covalent interactions between metal centers and organic linkers, have made the so-called metal-organic frameworks (MOFs) a flourishing area of enormous applicability. In this work, the extension of similar strategies to supramolecularly assembled metal-organic materials has allowed us to obtain a family of isoreticular compounds of the general formula [Cu7(µ-adeninato-κN3:κN9)6(µ3-OH)6(µ-OH2)6](OOC-R-COO)·nH2O (R: ethylene-, acetylene-, naphthalene-, or biphenyl-group) in which the rigid copper-adeninato entities and the organic dicarboxylate anions are held together not by covalent interactions but by a robust and flexible network of synergic hydrogen bonds and π-π stacking interactions based on well-known supramolecular synthons (SMOFs). All compounds are isoreticular, highly insoluble, and water-stable and show a porous crystalline structure with a pcu topology containing a two-dimensional (2D) network of channels, whose dimensions and degree of porosity of the supramolecular network are tailored by the length of the dicarboxylate anion. The partial loss of the crystallization water molecules upon removal from the mother liquor produces a shrinkage of the unit cell and porosity, which leads to a color change of the compounds (from blue to olive green) if complete dehydration is achieved by means of gentle heating or vacuuming. However, the supramolecular network of noncovalent interactions is robust and flexible enough to reverse to the expanded unit cell and color after exposure to a humid atmosphere. This humidity-driven breathing behavior has been used to design a sensor in which the electrical resistance varies reversibly with the degree of humidity, very similar to the water vapor adsorption isotherm of the SMOF. The in-solution adsorption properties were explored for the uptake and release of the widely employed 5-fluorouracil, 4-aminosalycilic acid, 5-aminosalycilic acid, and allopurinol drugs. In addition, cytotoxicity activity assays were completed for the pristine and 5-fluorouracil-loaded samples.

5.
Inorg Chem ; 62(42): 17444-17453, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37811902

RESUMO

A family of unprecedented supramolecularly assembled porous metal-organic compounds (SMOFs), based on [Cu6M(µ-adeninato)6(µ3-OH)6(µ-H2O)6]2+ cations (MII: Cu, Co, Ni, and Zn) and different dicarboxylate anions (fumarate, benzoate, and naphthalene-2,6-dicarboxylate), have been employed as precursors of catalysts for the thermocatalytic reduction of CO2. The selected metal-organic cation allows us to tune the composition of the SMOFs and, therefore, the features and performance of the final homometallic and bimetallic catalysts. These catalysts were obtained by thermolysis at 600 °C under a N2 atmosphere and consist of big metal particles (10-20 µm) placed on the surface of the carbonaceous matrix and very tiny metal aggregates (<10 nm) within this carbonaceous matrix. The latter are the most active catalytic sites for the CO2 thermocatalytic reduction. The amount of this carbonaceous matrix correlates with the organic content present in the metal-organic precursor. In this sense, CO2 thermocatalytic reduction experiments performed over the homometallic, copper only, catalysts with different carbon contents indicate that above a certain value, the increase of the carbonaceous matrix reduces the overall performance by encapsulating the nanoparticles within this matrix and isolating them from interacting with CO2. In fact, the best performing homometallic catalyst is that obtained from the precursor containing a small fumarate counterion. On the other hand, the structural features of these precursors also provide a facile route to work with a solid solution of nanoparticles as many of these metal-organic compounds can replace up to 1/7 of the copper atoms by zinc, cobalt, or nickel. Among these heterometallic catalysts, the best performing one is that of copper and zinc, which provides the higher conversion and selectivity toward CO. XPS spectroscopy and EDX mappings of the latter catalyst clearly indicate the presence of Cu1-xZnx nanoparticles covered by small ZnO aggregates that provide a better CO2 adsorption and easier CO release sites.

6.
Molecules ; 28(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37570613

RESUMO

The present study reports on a 2D lamellar coordination polymer (CP) of {[Zn(µ3-pmdc)(H2O)]·H2O}n formula (pmdc = pyrimidine-4,6-dicarboxylate). This CP is synthesized under an appropriate acid-base reaction between the gently mortared reagents in the solid state through a solvent-free procedure that avoids the presence of concomitant byproducts. The X-ray crystal structure reveals the occurrence of Zn2 entities connected through carboxylate groups of pmdc, which behave as triconnected nodes, giving rise to six-membered ring-based layers that are piled up through hydrogen bonding interactions. In addition to a routine physico-chemical characterization, the thermal evolution of the compound has been studied by combining thermogravimetric and thermodiffractometric data. The photoluminescence properties are characterized in the solid state and the processes governing the spectra are described using time-dependent density-functional theory (TD-DFT) with two different approaches employing different program packages. The emissive capacity of the material is further analyzed according to the dehydration and decreasing temperature of the polycrystalline sample.

7.
Commun Chem ; 6(1): 4, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36697803

RESUMO

Nowadays, there are many reliable characterization techniques for the study of adsorption properties in gas phase. However, the techniques available for the study of adsorption processes in solution, rely on indirect characterization techniques that measure the adsorbate concentration remaining in solution. In this work, we present a sensing method based on the magnetic properties of metal-organic frameworks (MOFs) containing paramagnetic metal centres, which stands out for the rapidity, low cost and in situ direct measurement of the incorporated adsorbate within the porous material. To illustrate this sensing technique, the adsorption in solution of four MOFs have been characterized: MIL-88A(Fe), MOF-74(Cu, Co) and ZIF-67(Co). Our simple and efficient method allows the direct determination of the adsorbed mass, as well as the measurement of adsorption isotherm curves, which we hope will greatly advance the study of adsorption processes in solution, since this method is independent of the chemical nature of the adsorbate that often makes its quantification difficult.

8.
Sci Rep ; 12(1): 8505, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35595765

RESUMO

The doping of zirconium based EHU-30 and EHU-30-NH2 metal-organic frameworks with copper(II) yielded a homogeneous distribution of the dopant with a copper/zirconium ratio of 0.04-0.05. The doping mechanism is analysed by chemical analysis, microstructural analysis and pair distribution function (PDF) analysis of synchrotron total scattering data in order to get deeper insight into the local structure. According to these data, the Cu(II) atoms are assembled within the secondary building unit by a transmetalation reaction, contrarily to UiO-66 series in which the post-synthetic metalation of the MOF takes place through chemical anchorage. The resulting materials doubled the overall performance of the parent compounds for the CO2 electroreduction, while retained stable the performance during continuous transformation reaction.

9.
Inorg Chem ; 61(12): 4842-4851, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35286083

RESUMO

Clustering chemistry is a key point in the design and synthesis of the secondary building units that comprise metal-organic frameworks (MOFs) based on group IV metals. In this work, the first stages of the zirconium-carboxylate clustering process in alcohol/water mixtures are studied in detail using the monocarboxylic benzoic and hydroxybenzoic acids to avoid the polymerization. Mass spectroscopy measurements performed on the reactions revealed the presence of hexa- and pentanuclear species even at low pH values and also evidenced the acid-base nature and pH dependence of the transformation between both species. The control on the chemistry governing the equilibria between these species has allowed us to isolate six new compounds in the solid state. The single-crystal X-ray diffraction analysis revealed that they are closely related to the well-known [Zr6(O)4(OH)4(OOC)12] secondary building unit found in many MOFs by removing carboxylic ligands in the case of the hexameric species ([Zr6(O)4(OH)4(OOC)8(H2O)8]4+) or by additionally removing one of the metal centers in the case of the pentameric entities ([Zr5(O)2(OH)6(OOC)4(H2O)11(alcohol)]6+). Going in detail, the unsaturated hexameric clusters exhibit different dispositions of their eight carboxylate ligands in such a way that the remaining four carboxylate-free positions are arranged according to a square planar or tetrahedral symmetry. It should be highlighted that the pentameric complexes imply an unprecedented core nuclearity in zirconium clusters and thus their isolation provides a novel building block for the design of metal-organic materials.

10.
Biofactors ; 47(4): 551-569, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33878238

RESUMO

Coenzyme Q10 (CoQ10 ) deficiency is a rare disease characterized by a decreased accumulation of CoQ10 in cell membranes. Considering that CoQ10 synthesis and most of its functions are carried out in mitochondria, CoQ10 deficiency cases are usually considered a mitochondrial disease. A relevant feature of CoQ10 deficiency is that it is the only mitochondrial disease with a successful therapy available, the CoQ10 supplementation. Defects in components of the synthesis machinery caused by mutations in COQ genes generate the primary deficiency of CoQ10 . Mutations in genes that are not directly related to the synthesis machinery cause secondary deficiency. Cases of CoQ10 deficiency without genetic origin are also considered a secondary deficiency. Both types of deficiency can lead to similar clinical manifestations, but the knowledge about primary deficiency is deeper than secondary. However, secondary deficiency cases may be underestimated since many of their clinical manifestations are shared with other pathologies. This review shows the current state of secondary CoQ10 deficiency, which could be even more relevant than primary deficiency for clinical activity. The analysis covers the fundamental features of CoQ10 deficiency, which are necessary to understand the biological and clinical differences between primary and secondary CoQ10 deficiencies. Further, a more in-depth analysis of CoQ10 secondary deficiency was undertaken to consider its origins, introduce a new way of classification, and include aging as a form of secondary deficiency.


Assuntos
Envelhecimento/genética , Alquil e Aril Transferases/genética , Ataxia/genética , GTP Fosfo-Hidrolases/genética , Mitocôndrias/genética , Doenças Mitocondriais/genética , Proteínas Mitocondriais/genética , Debilidade Muscular/genética , Doença de Niemann-Pick Tipo C/genética , Ubiquinona/análogos & derivados , Ubiquinona/deficiência , Envelhecimento/metabolismo , Alquil e Aril Transferases/metabolismo , Animais , Ataxia/metabolismo , Ataxia/patologia , Metabolismo Energético/genética , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Doenças Mitocondriais/metabolismo , Doenças Mitocondriais/patologia , Proteínas Mitocondriais/metabolismo , Debilidade Muscular/metabolismo , Debilidade Muscular/patologia , Mutação , Proteína C1 de Niemann-Pick/genética , Proteína C1 de Niemann-Pick/metabolismo , Doença de Niemann-Pick Tipo C/metabolismo , Doença de Niemann-Pick Tipo C/patologia , Transdução de Sinais , Ubiquinona/genética , Ubiquinona/metabolismo
11.
Nat Commun ; 12(1): 1237, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33623012

RESUMO

Immunotherapy has raised high expectations in the treatment of virtually every cancer. Many current efforts are focused on ensuring the efficient delivery of active cytotoxic cells to tumors. It is assumed that, once these active cytotoxic cells are correctly engaged to cancer cells, they will unfailingly eliminate the latter, provided that inhibitory factors are in check. T cell bispecific antibodies (TCBs) and chimeric antigen receptors (CARs) offer an opportunity to test this assumption. Using TCB and CARs directed against HER2, here we show that disruption of interferon-gamma signaling confers resistance to killing by active T lymphocytes. The kinase JAK2, which transduces the signal initiated by interferon-gamma, is a component repeatedly disrupted in several independently generated resistant models. Our results unveil a seemingly widespread strategy used by cancer cells to resist clearance by redirected lymphocytes. In addition, they open the possibility that long-term inhibition of interferon-gamma signaling may impair the elimination phase of immunoediting and, thus, promote tumor progression.


Assuntos
Anticorpos Biespecíficos/imunologia , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/imunologia , Janus Quinase 2/metabolismo , Neoplasias/imunologia , Receptor ErbB-2/metabolismo , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/imunologia , Animais , Linhagem Celular , Citotoxicidade Imunológica , Humanos , Interferon gama/metabolismo , Camundongos , Transdução de Sinais , Transcriptoma/genética
12.
Sci Data ; 7(1): 203, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32587252

RESUMO

This dataset provides long-term information on the presence of the Iberian ibex (Capra pyrenaica hispanica Schimper, 1848) in Sierra Nevada (SE Iberian Peninsula). Data on the abundance and demographic structure of the Iberian ibex population were compiled over the last three decades. Transects were laid out to record different variables such as the number of individuals sighted, the perpendicular distance of each group of Iberian ibex to the transect line and sex as well as age of individuals in the case of males. These data enabled the calculation of population parameters such as density, sex ratio, birth rate, and age structure. These parameters are key for Iberian ibex conservation and management, given that Sierra Nevada harbours the largest population of this species in the Iberian Peninsula. The data set we present is structured using the Darwin Core biological standard, which contains 3,091 events (582 transect walk events and 2,509 group sighting events), 5,396 occurrences, and 2,502 measurements. The occurrences include the sightings of 11,436 individuals (grouped by sex and age) from 1993 to 2018 in a total of 88 transects distributed along Sierra Nevada, of which 33 have been continuously sampled since 2008.


Assuntos
Cabras , Animais , Coeficiente de Natalidade , Densidade Demográfica , Razão de Masculinidade , Espanha
13.
Cancers (Basel) ; 12(3)2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32183023

RESUMO

Trastuzumab-emtansine (T-DM1) is an antibody-drug conjugate (ADC) approved for the treatment of HER2 (human epidermal growth factor receptor 2)-positive breast cancer. T-DM1 consists of trastuzumab covalently linked to the cytotoxic maytansinoid DM1 via a non-cleavable linker. Despite its efficacy, primary or acquired resistance frequently develops, particularly in advanced stages of the disease. Second generation ADCs targeting HER2 are meant to supersede T-DM1 by using a cleavable linker and a more potent payload with a different mechanism of action. To determine the effect of one of these novel ADCs, SYD985, on tumors resistant to T-DM1, we developed several patient-derived models of resistance to T-DM1. Characterization of these models showed that previously described mechanisms-HER2 downmodulation, impairment of lysosomal function and upregulation of drug efflux pumps-account for the resistances observed, arguing that mechanisms of resistance to T-DM1 are limited, and most of them have already been described. Importantly, SYD985 was effective in these models, showing that the resistance to first generation ADCs can be overcome with an improved design.

14.
J Inorg Biochem ; 202: 110865, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669692

RESUMO

Two planar organic anions, benzoate and benzene-1,4-dicarboxylate (terephthalate), have been selected as potential π-stacking intercalators among ferrimagnetic [Cu7(µ-adeninato)6(µ3-OH)6(µ-H2O)6]2+ heptameric discrete entities. The resulting supramolecular architecture is highly dependent on the negative charge density distribution, mainly located in the carboxylate groups of the organic anions. In this sense, the benzoate anion, with just one carboxylate group, does not allow its intercalation between the adeninato ligands as it would imply a high steric hindrance among the heptameric entities. As a consequence, these benzoate anions are located inside the voids of the crystal structure reducing the accessible volume of compound [Cu7(µ-adeninato)6(µ3-OH)6(µ-H2O)6](benzoate)2·~17H2O (1). On the contrary, the terephthalate anion, containing two carboxylate groups at opposite sites, adopts a π-stacking sandwich arrangement between two adeninato ligands that affords the porous open structure of formula [Cu7(µ-adeninato)6(µ3-OH)6(µ-H2O)6](terephthalate)·nH2O (2a, 2b; n: 12 and 24, respectively). In addition to that, the less directional nature of the π-stacking interactions in comparison to the complementary hydrogen bonding based supramolecular metal-organic frameworks (SMOFs), suits them with a flexible architecture able to reversibly adsorb/desorb water (up to a 25-30% at 20 °C) altogether with the expansion/shrinkage of the crystal structure. The bridging adeninato and hydroxido ligands are effective magnetic exchange mediators to provide a ST = 5/2 ferrimagnetic state for the heptanuclear entity.


Assuntos
Adenina/química , Ânions/química , Ácidos Carboxílicos/química , Cobre/química , Compostos Férricos/química , Magnetismo , Estruturas Metalorgânicas/química , Modelos Moleculares , Estrutura Molecular
15.
Zookeys ; 852: 125-136, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31210747

RESUMO

This dataset provides information about infestation caused by the pine processionary moth (Thaumetopoeapityocampa ([Denis & Schiffermüller], 1775)) in pure or mixed pine woodlands and plantations in Andalusia. It represents a long-term series (1993-2015) containing 81,908 records that describe the occurrence and incidence of this species. Data were collected within a monitoring programme known as COPLAS, developed by the Regional Ministry of Environment and Territorial Planning of the Andalusian Regional Government within the frame of the Plan de Lucha Integrada contra la Procesionaria del Pino (Plan for Integrated Control Against the Pine Processionary Moth). In particular, this dataset includes 4,386 monitoring stands which, together with the campaign year, define the dataset events in Darwin Core Archive. Events are related with occurrence data which show if the species is present or absent. In turn, the event data have a measurement associated: degree of infestation.

16.
Chem Commun (Camb) ; 55(42): 5954-5957, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31049494

RESUMO

Since its discovery in 2008, the paradigmatic UiO-66 has behaved as the germ that has prompted the chemistry of group-4 metal based metal-organic frameworks, all of them featuring outstanding thermal and chemical stability. Herein we present the first polymorph of UiO-66 and the key conditions that led to its formation.

17.
Physiol Behav ; 198: 134-139, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30389476

RESUMO

Sleeping problems can affect physiological adaptations and the recovery process. The aim of this study was to analyse the effect of the intensity and the hour of the training session on sleep quality and cardiac autonomic activity in amateur ultra-endurance athletes. We used a comparative, randomized crossover design to test the effect of moderate (M) or vigorous (V) intensity and morning (m) or evening (e) training journey, separated by 72 h of recovery, on actigraphic and subjective sleep quality and nocturnal cardiac autonomic activity in fourteen ultra-endurance male runners. No significant differences among training sessions were found in nocturnal heart rate variability or in subjective sleep quality, but participants experienced significantly higher calm sleep after Mm than Me (p = 0.028; ES = 0.7) and more refreshed after awakening when they performed a Me than Vm (p = 0.04; ES = 0.6). Higher sleep efficiency was found when the training is performed in the morning compared to the evening sessions in both intensities, and it was also observed in Me vs Ve (p = 0.012; ES = 0.8). Significantly lower numbers of awakenings were observed when the training was performed in the morning, and actual sleep time was significantly lower when participants performed a vigorous training session compared to a moderate one (Vm vs Mm: p = 0.035; ES = 0.6; Ve vs Mm: p = 0.036; ES = 0.6). Moderate exercise performed in the morning had a higher sleep efficiency compared to other types of training and intensity training is more important than the time of the day of training on sleep quality.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Frequência Cardíaca/fisiologia , Corrida/fisiologia , Sono/fisiologia , Actigrafia , Adaptação Fisiológica/fisiologia , Adulto , Exercício Físico/fisiologia , Humanos , Masculino , Resistência Física/fisiologia , Adulto Jovem
18.
Sci Transl Med ; 10(461)2018 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-30282693

RESUMO

T cell bispecific antibodies (TCBs) are engineered molecules that include, within a single entity, binding sites to the T cell receptor and to tumor-associated or tumor-specific antigens. The receptor tyrosine kinase HER2 is a tumor-associated antigen in ~25% of breast cancers. TCBs targeting HER2 may result in severe toxicities, likely due to the expression of HER2 in normal epithelia. About 40% of HER2-positive tumors express p95HER2, a carboxyl-terminal fragment of HER2. Using specific antibodies, here, we show that p95HER2 is not expressed in normal tissues. We describe the development of p95HER2-TCB and show that it has a potent antitumor effect on p95HER2-expressing breast primary cancers and brain lesions. In contrast with a TCB targeting HER2, p95HER2-TCB has no effect on nontransformed cells that do not overexpress HER2. These data pave the way for the safe treatment of a subgroup of HER2-positive tumors by targeting a tumor-specific antigen.


Assuntos
Anticorpos Biespecíficos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Receptor ErbB-2/imunologia , Linfócitos T/imunologia , Animais , Neoplasias da Mama/patologia , Complexo CD3/imunologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Clin Transplant ; 32(12): e13433, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30365182

RESUMO

BACKGROUND AND AIMS: Biliary anastomosis is a frequent area of complications after liver transplantation (LT) and a potential area of "microangiopathy". The concept of a "marginal bile duct" is unexplored. The main aim was to make a preliminary evaluation of the utility of an innovative real-time oxygen microtension (pO2mt) testing device for the assessment of bile duct viability during LT and to correlate these pO2mt values with microvascular tissue quality by histopathology and outcomes. PATIENTS AND METHODS: Observational prospective cohort study with 23 patients. Oxygen microtension measurements were made placing a micropO2 probe in different areas of recipient and donor's bile duct intraoperative. RESULTS: Mean pO2mt in the graft bile duct at the level of the anastomosis 103.82 (31-157) mm Hg, being 121.52 (55-174) mm Hg 1.5 cm proximal to the hilar plate (P < 0.001). Mean pO2mt in the recipient's bile duct was 117.87 (62-185) mm Hg, while a value of 137.30 (81-198) mm Hg was observed 1.5 cm distal to the anastomosis (P < 0.001). Cystic duct resection (12 cases) was also related with higher pO2mt values at anastomosis [117.8 (93-157) vs 88.54 (31-124) mm Hg] and distal to anastomosis [135.6 (111-174) vs 106.2 (55-133) mm Hg; P < 0.001]. Patients with 1-, 3-, and 12-month biliary complications had significantly lower pO2mt in the intraoperative measurements. CONCLUSION: Our preliminary results show that distal borders of donor and recipient bile ducts may be low-vascularized areas. Tissue pO2mt is significantly higher in areas close to the hilar plate and to the duodenum in donor and recipient's sides, respectively. Bile duct injury and biliary complications are associated with worse tissue pO2mt.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Doenças Biliares/diagnóstico , Sistema Biliar/metabolismo , Complicações Intraoperatórias/diagnóstico , Transplante de Fígado/efeitos adversos , Doadores Vivos/provisão & distribuição , Oxigênio/metabolismo , Sistema Biliar/patologia , Doenças Biliares/etiologia , Doenças Biliares/metabolismo , Feminino , Seguimentos , Humanos , Complicações Intraoperatórias/etiologia , Complicações Intraoperatórias/metabolismo , Masculino , Pessoa de Meia-Idade , Oxigênio/efeitos adversos , Oxigênio/análise , Prognóstico , Estudos Prospectivos , Fatores de Risco
20.
J Sport Health Sci ; 6(4): 468-473, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30356606

RESUMO

PURPOSE: The aim of this study was to determine if heart rate variability (HRV) during incremental test could be used to estimate ventilatory threshold (VT) in professional basketball players, with sufficient precision to be used in their training. Furthermore, the second aim was to analyse the association between HRV and 3 methods of VT determination by gas analysis. METHODS: Twenty-four professional basketball players (age: 23.4 ± 4.9 years; height: 195.4 ± 9.8 cm; body mass: 92.2 ± 11.9 kg) performed an incremental running test to exhaustion. First ventilatory threshold (VT1) was determined by ventilatory equivalent (VE) and HRV and second ventilatory threshold (VT2) was determined by 3 methods of gases analysis (V-slope, VE and gas exchange ratio (R), and HRV). Pearson's coefficient (r) was used to detect differences between data and the strength of each relationship. The mean of absolute differences and Bland-Altman analysis were used to evaluate whether there was agreement. RESULTS: The results showed no significant differences in HR and oxygen consumption (VO2) at VT1 between the 2 methods. Furthermore, no significant differences among the methods of gases analysis and HRV were observed in speed, HR, and VO2 at VT2. Moreover, VTs estimated using HRV and gas methods were significantly correlated. Correlation in HR values was higher between R and HRV (r = 0.96) and VE and HRV (r = 0.96) than V-slope and HRV (r = 0.90). CONCLUSION: These findings provide a practical, inexpensive approach for evaluating specific training loads when determining VT2 in basketball players. Therefore, HRV is an alternative method to determine VT2 without the application of expensive technology that limits its use to laboratories.

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