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1.
Am J Dermatopathol ; 45(8): e61-e63, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-37378474

ABSTRACT

ABSTRACT: Self-healing juvenile cutaneous mucinosis is a rare entity, characterized by the presence of subcutaneous nodules together with frequent nonspecific systemic symptoms, which occurs in the pediatric age and characteristically resolves spontaneously. Although the diagnostic criteria do not require a biopsy to be performed, it is frequently performed, and an abundant dermal mucin deposition will be observed together with other features such as fibroblastic proliferation. Although the prognosis is benign, follow-up is required for the eventual development of a rheumatologic disease.We present 2 clinical cases, describing the clinical findings and their histopathologic correlation. Comparatively, the outcome in both cases was different: in one case, the mucinosis resolved without any related event in the follow-up, and in the other case, the resolution was accompanied by the subsequent development of idiopathic juvenile arthritis.


Subject(s)
Arthritis, Juvenile , Mucinoses , Skin Diseases , Humans , Child , Mucinoses/pathology , Biopsy , Mucins
2.
Mol Ecol ; 27(8): 1952-1965, 2018 04.
Article in English | MEDLINE | ID: mdl-29420863

ABSTRACT

Bacterial communities play an essential role for the function of marine macroalgae. Recent work has shown that bacterial communities associated with individual macroalgae possess on a local scale a functional core that is likely derived from diverse members of functional guilds. It is not known whether such functional cores also exist across large spatial scales or between closely related host species. To address this, we studied here the bacterial communities on three species of the green macroalgal genus Ulva from different geographic locations. While the taxonomic composition was too variable to describe a community core, we identified genes that were enriched across all Ulva samples as compared to the communities of the surrounding seawater. Of these core functions, 70% were consistently found and independent of the Ulva species and biogeography, while the remaining functions (~30%) are possibly involved in local or host-specific adaptations. For each host individual, the core functions are provided by bacteria with distinct phylogenetic origin and these bacteria could constitute a global guild of Ulva-associated bacteria. Together, our results demonstrate the presence of a stable core set of functional genes in the bacterial communities associated with closely related host species and across large biogeographies.


Subject(s)
Bacteria/genetics , Host Specificity/genetics , Phylogeography , Ulva/microbiology , Bacteria/classification , RNA, Ribosomal, 16S/genetics , Seawater , Ulva/genetics
3.
J Invertebr Pathol ; 133: 50-8, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26628210

ABSTRACT

A survey on perkinsosis was performed involving 15 locations scattered along the Galician coast (NW Spain) and four clam species with high market value (Ruditapes decussatus, Ruditapes philippinarum, Venerupis corrugata and Polititapes rhomboides). The prevalence of Perkinsus parasites was estimated by PCR using genus-specific primers. The highest percentage of PCR-positive cases for perkinsosis corresponded to clams R. decussatus and V. corrugata, while lower values were detected in R. philippinarum and no case was found in P. rhomboides. The discrimination of Perkinsus species was performed by PCR-RFLP and by a new PCR-DGGE method developed in this study. Perkinsus olseni was identified in every clam species, except in P. rhomboides, using both PCR-DGGE and PCR-RFLP. Additionally, Perkinsus chesapeaki was only detected by PCR-DGGE infecting two Manila clams R. philippinarum from the same location, reporting the first case in Galicia. P. chesapeaki identification was further confirmed by in situ hybridisation assay and phylogenetic analysis of ITS region and LSU rDNA.


Subject(s)
Alveolata/genetics , Bivalvia/parasitology , Alveolata/classification , Alveolata/isolation & purification , Animals , In Situ Hybridization , Likelihood Functions , Phylogeny , Polymerase Chain Reaction/methods , Sequence Analysis, DNA , Spain , Species Specificity
4.
Curr Microbiol ; 69(3): 329-33, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24801334

ABSTRACT

A Gram-positive, aerobic, non-motile, non-sporulating, acid-fast, and rod-shaped bacterium (BFLP-6(T)), previously isolated from a seahorse (Hippocampus guttulatus) with tail rot, was studied using a polyphasic taxonomic approach. Growth occurred at 15-35 °C (optimum 25 °C), at pH 5.0-10.0 (optimum pH 7.0) and at NaCl concentrations between 0 and 6 % (w/v). The G+C content of DNA was 66.7 mol%. The predominant fatty acids were C(18:1) ω9c, C(16:0) and C(16:1) ω6c. A mycolic acid pattern of alpha-mycolates and keto-mycolates was detected. Analysis of concatenated sequences (16S rRNA, rpoB, ssrA and tuf genes), and chemotaxonomic and phenotypic features indicated that strain BFLP-6(T) represents a novel species within the genus Mycobacterium, for which the name Mycobacterium hippocampi sp. nov. is proposed. The type strain is BFLP-6(T) (=DSM 45391(T) =LMG 25372(T)).


Subject(s)
Nontuberculous Mycobacteria/classification , Nontuberculous Mycobacteria/isolation & purification , Smegmamorpha/microbiology , Animals , Bacterial Proteins/genetics , Bacterial Typing Techniques , Base Composition , Cluster Analysis , Cytosol/chemistry , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA-Directed RNA Polymerases , Fatty Acids/analysis , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Molecular Sequence Data , Mycobacterium Infections/microbiology , Mycolic Acids/analysis , Nontuberculous Mycobacteria/genetics , Nontuberculous Mycobacteria/physiology , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sodium Chloride/metabolism , Tail/microbiology , Temperature
5.
Medicine (Baltimore) ; 103(9): e37328, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38428901

ABSTRACT

Obesity is an ignored health problem in all countries; there are a lot of health problems related directly or indirectly to overweight and obesity. The incidence of COVID-19 with social isolation and technological development in recent years strongly contributed to a progressive increase in obesity. . Assess the pattern of the 3 divisions of physical activity and sedentary behaviors in obese patients. Physical inactivity is a significant concern, especially among individuals with obesity and certain demographic characteristics. Addressing these factors and promoting physical activity interventions tailored to specific populations is essential in combating sedentary behavior and its associated health implications.This case-control study included 350 adult obese patients (BMI ≥ 30) and 75 people with normal BMI (18.5-24.9). Their sociodemographic data were analyzed and their pattern of physical activity related to work, movement to and from places for 10 minutes, and pattern of recreational activity were assessed, in addition to the assessment of the sedentary behaviors. The mean age of the study group was 34 years, the majority were females, educated, and working. Forty five percent of the total sample were physically inactive; the pattern of activity during travel to and from places (10 min) was lower in obese patients. Recreational activities were low in the studied population, in the present study the time spent sitting or reclining (except sleeping) was significantly higher among obese participants than controls (P ≤ .001). Obesity, urban residence, unemployment and illiteracy were independent risk factors for physical inactivity.


Subject(s)
Exercise , Obesity , Adult , Female , Humans , Male , Case-Control Studies , Egypt/epidemiology , Obesity/epidemiology , Obesity/etiology , Overweight/epidemiology , Primary Health Care
6.
Maxillofac Plast Reconstr Surg ; 46(1): 11, 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38538984

ABSTRACT

BACKGROUND: Early oral feeding has been previously postulated to contribute to developing postoperative complications following head and neck reconstructive surgeries using free flaps. This study assessed the association between the timing of oral feeding (early vs. late) and postoperative complications and length of hospital stay among these patients. METHOD: PubMed, Scopus, Cochrane, and Web of Science were searched using terms such as "oral feeding" and "head or neck cancer." We utilized RevMan software version 5.4 for the analysis. The study defined early oral feeding as feeding within 5-day post-operation, while late oral feeding was defined as feeding after the fifth postoperative day. Five papers that met the inclusion criteria were included in the analysis, with 1097 patients. RESULTS: The results showed that early feeding was not significantly associated with postoperative fistulas (RR 0.49, 95% CI 0.23 to 1.05, p-value = 0.07), hematoma/seroma (RR 0.71, 95% CI 0.33 to 1.51, p-value = 0.38), or flap failure (RR 0.84, 95% CI = 0.38 to 1.87, p-value = 0.67). However, early oral feeding was significantly associated with shorter hospital stays than late oral feeding (MD -3.18, 95% CI -4.90 to -1.46, p-value = 0.0003). CONCLUSION: No significant difference exists between early and late oral feeding regarding the risk of postoperative complications in head and neck cancer (HNC) patients who underwent free flap reconstruction surgery. However, early oral feeding is significantly associated with a shorter hospital stay than late oral feeding. Thus, surgeons should consider implementing early oral feeding after free flap reconstruction in HNC patients.

7.
Ann Med Surg (Lond) ; 86(10): 6105-6120, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39359774

ABSTRACT

Background: The intestinal microbiome has been recently linked to several metabolic and chronic disorders, one of which is coronary artery disease (CAD). Our study aimed to analyze the intestinal microbiome of CAD patients and assess the eligibility of dysbiosis as a diagnostic marker of CAD. Methods: PubMed, Scopus, Embase, and Web of Science were searched using terms, such as 'CAD' and 'microbiome'. Only observational controlled studies were included. R version 4.2.2 was used for the analysis. Results: A significant association was found between the CAD group and increased Simpson and Shannon Indices compared with the control group (MD=0.04, 95% CI=0.03-0.05, and MD=0.11, 95% CI=0.01-0.22, respectively). Our analysis yielded a statistically significant association between the CAD group and increased Prevotella genus (MD=13.27, 95% CI=4.12-22.42, P-value=0.004), Catenibacterium genus (MD=0.09, 95% CI=0.09-0.10), Pseudomonas genus (MD=0.54, 95% CI=0.29-0.78, P-value), and Subdoligranulum (MD=-0.06, 95% CI=-0.06 to -0.06) compared with the control group. Another significant association was detected between the CAD group and decreased Bacteroides vulgatus and Bacteroides dorei (MD=-10.31, 95% CI=-14.78 to -5.84, P-value <0.00001). Conclusion: Dysbiosis is an acceptable diagnostic marker of CAD. Decreased B. dorei and B. vulgatus among CAD patients suggests a protective role of these bacteria. Future clinical trials are necessary to investigate the potential benefit of supplementation of these bacteria in treating or preventing CAD.

8.
Endocrinol Diabetes Metab ; 7(3): e473, 2024 May.
Article in English | MEDLINE | ID: mdl-38597269

ABSTRACT

BACKGROUND: Previous meta-analyses have shown mixed results regarding the association between eating disorders (EDs) and type 1 diabetes mellitus (T1DM). Our paper aimed to analyse different EDs and disordered eating behaviours that may be practiced by patients with T1DM. METHODS: A literature search of PubMed, Scopus and Web of Science was conducted on 17 January 2023, using the key terms "T1DM," "Eating Disorders" and "Bulimia." Only observational controlled studies were included. The Revman software (version 5.4) was used for the analysis. RESULTS: T1DM was associated with increased risk of ED compared with nondiabetic individuals (RR = 2.47, 95% CI = 1.84-3.32, p-value < 0.00001), especially bulimia nervosa (RR = 2.80, 95% CI = 1.18-6.65, p-value = 0.02) and binge eating (RR = 1.53, 95% CI = 1.18-1.98, p-value = 0.001). Our analysis has shown that increased risk of ED among T1DM persisted regardless of the questionnaire used to diagnose ED; DM-validated questionnaires (RR = 2.80, 95% CI = 1.91-4.12, p-value < 0.00001) and generic questionnaires (RR = 2.03, 95% CI = 1.27-3.23, p-value = 0.003). Prevalence of insulin omission/misuse was 10.3%; diabetic females demonstrated a significantly higher risk of insulin omission and insulin misuse than diabetic males. CONCLUSION: Our study establishes a significant and clear connection between EDs and T1DM, particularly bulimia and binge eating, with T1DM. Moreover, female diabetics are at higher risk of insulin misuse/omission. Early proactive screening is essential and tailored; comprehensive interventions combining diabetes and ED components are recommended for this population, with referral to a specialised psychiatrist.


Subject(s)
Bulimia , Diabetes Mellitus, Type 1 , Feeding and Eating Disorders , Male , Humans , Female , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/epidemiology , Bulimia/complications , Feeding and Eating Disorders/complications , Feeding and Eating Disorders/epidemiology , Insulin , Insulin, Regular, Human
9.
Microorganisms ; 11(11)2023 Nov 06.
Article in English | MEDLINE | ID: mdl-38004727

ABSTRACT

Bacterial communities associated with fish larvae are highly influenced by the microbiota of live prey used as feed (rotifers or Artemia), generally dominated by bacterial strains with a low degree of specialization and high growth rates, (e.g., Vibrionaceae), which can be detrimental to larvae. Co-cultivation of microalgae used in the enrichment of Artemia (e.g., Phaeodactylum tricornutum, or Chlorella minutissima) with Vibrio-antagonistic probiotics belonging to the Roseobacter clade bacteria (e.g., Phaeobacter spp. or Ruegeria spp.) was studied. The introduction of the probiotics did not affect microalgae growth or significantly modify the composition of bacterial communities associated with both microalgae, as revealed by DGGE analysis. The inoculation of P. tricornutum with Ruegeria ALR6 allowed the maintenance of the probiotic in the scale-up of the microalgae cultures, both in axenic and non-axenic conditions. Using Ruegeria-inoculated P. tricornutum cultures in the enrichment of Artemia reduced the total Vibrionaceae count in Artemia by 2 Log units, therefore preventing the introduction of opportunistic or pathogenic bacteria to fish larvae fed with them.

10.
Sports (Basel) ; 11(1)2023 Jan 09.
Article in English | MEDLINE | ID: mdl-36668719

ABSTRACT

Incremental tests to exhaustion have been usually employed as the "gold standard" to establish the fitness level of athletes. However, during real competition in many sport disciplines, exertion is not characterized by an increasing effort until failure. The purpose of this preliminary study was to add new evidence regarding the usability of parameters obtained from an on-field testing in 800 m running athletes. V˙O2 kinetics (mean, amplitude, phase time, and phase start time) and biomechanical parameters (velocity, stride frequency, and stride length) were analyzed in eight athletes during a maximal 800 m running race test. Our results showed that only the peak of blood lactate concentration after the 800 m test was correlated with the race time (p = 0.047). The race time was positively associated with both the phase duration and phase start time (all p-values < 0.05). Conversely, race time was negatively correlated with velocity, stride frequency, and amplitude (p-values < 0.05). Our results reveal that jointly studying the V˙O2 kinetics and biomechanical parameters during a maximal 800 m running race test is a useful tool to predict the athlete's upcoming performance and improve the planning and control of the training process of 800 m running athletes.

11.
Photodiagnosis Photodyn Ther ; 44: 103820, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37788795

ABSTRACT

INTRODUCTION: Non-melanoma skin cancer within previously irradiated areas presents a common challenge, requiring innovative therapies. Complex scenarios, like XRT-induced basal cell carcinoma (BCC) or Gorlin's syndrome, often involve multiple synchronous tumor lesions where photodynamic therapy (PDT) offers a viable therapeutic alternative. CLINICAL CASE: We present the case of a 49-year-old male with a history of XRT for brain tumors. The patient was undergoing treatment for recurrent basal cell carcinomas (BCCs) in the right temporal irradiated area, unresponsive to conventional treatments. In the latest evaluation, the patient presented a nodular tumor and several peripheral superficial foci. Photodynamic therapy (PDT) was administered using methyl aminolevulinate 160 mg/g in cream (Metvix®) in two sessions spaced 7 days apart before surgery. The photosensitizer was applied 3 h before initiating PDT, and red light exposure was performed with the Aktilite© lamp (wavelength 630 nm, 100 mm distance, voltage 100 to 240 V, frequency 50 Hz, power 180 W) for 7 min. CONCLUSIóN: PDT with methyl aminolevulinate demonstrated efficacy as a neoadjuvant treatment in a case of multiple XRT-induced BCCs before surgery. PDT emerges as a valuable therapeutic alternative for multiple BCCs, particularly in non-responsive cases.


Subject(s)
Basal Cell Nevus Syndrome , Carcinoma, Basal Cell , Photochemotherapy , Skin Neoplasms , Male , Humans , Middle Aged , Photosensitizing Agents/therapeutic use , Neoadjuvant Therapy , Skin Neoplasms/pathology , Photochemotherapy/methods , Carcinoma, Basal Cell/drug therapy , Carcinoma, Basal Cell/radiotherapy , Carcinoma, Basal Cell/pathology , Aminolevulinic Acid/therapeutic use , Basal Cell Nevus Syndrome/drug therapy , Treatment Outcome
12.
Ann Med Surg (Lond) ; 85(12): 6123-6133, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38098555

ABSTRACT

Background and Aim: Recent studies have linked trimethylamine N-oxide (TMAO) to cardiovascular diseases; our study aimed to analyze the association between coronary artery disease (CAD), acute coronary syndrome (ACS), and TMAO. Methods: PubMed, Scopus, Embase, and Web of Science were searched using terms such as 'CAD' and 'TMAO'. Only observational controlled studies were included. RevMan software version 5.4 was used for the analysis. Results: A significant association was found between the CAD group and increased serum TMAO levels compared with the control group (MD=1.16, 95% CI=0.54-1.78, P=0.0003). This association remained significant among acute coronary syndrome patients (MD=0.98, 95% CI=0.73-1.23, P<0.00001) and was also detected among young and old CAD patients (MD=0.35, 95% CI=0.06-0.64, P=0.02 and MD=1.36, 95% CI=0.71-2.01, P<0.0001, respectively). On further analysis of intestinal metabolites, the authors detected an insignificant association between choline, betaine, carnitine, and CAD. According to our sensitivity analysis, TMAO is an acceptable diagnostic marker for CAD (0.721, SE was 0.0816, 95% CI: 0.561-0.881). Conclusion: TMAO is an acceptable diagnostic marker for CAD, with significantly higher levels among these patients regardless of their age. Other metabolites did not show such an association. The role of serum level TMAO in the early diagnosis of CAD should be further explored.

13.
Antonie Van Leeuwenhoek ; 102(1): 187-91, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22453519

ABSTRACT

A Gram-negative, aerobic, motile and slightly curved rod-shaped bacterium (BFLP-8(T)) was isolated from cutaneous mucus of wild long-snouted seahorses (Hippocampus guttulatus) captured in northwest Spain (Toralla, Galicia). Strain BFLP-8(T) grew at 10-35 °C and pH 5-9 (optimally at 25 °C and pH 7.0) and with 1-6 % (w/v) NaCl (optimally with 2 % NaCl). The predominant respiratory quinone (90 %) was ubiquinone with ten isoprene units (Q-10) and the major fatty acids identified were C(18:1) ω7c (54.8 % of the total), C(19:0) cyclo ω8c (11.6 %), C(16:0) (9.5 %), C(18:1) 2-OH (7.1 %) and C(16:1) ω11c (6.7 %). The G+C content of the DNA was 57.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain BFLP-8(T) formed a distinct clade within the family Sneathiellaceae but is not specifically associated with any species in the family. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain BFLP-8(T) represents a novel species within a new genus, for which the name Oceanibacterium hippocampi gen. nov., sp. nov. is proposed. The type strain is BFLP-8(T) (=CECT 7691(T) = DSM 23444(T)).


Subject(s)
Alphaproteobacteria/classification , Alphaproteobacteria/isolation & purification , Smegmamorpha/microbiology , Alphaproteobacteria/genetics , Alphaproteobacteria/physiology , Animals , Base Composition , Cluster Analysis , Cytosol/chemistry , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Fatty Acids/analysis , Hydrogen-Ion Concentration , Molecular Sequence Data , Mucus/microbiology , Phylogeny , Quinones/analysis , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sodium Chloride/metabolism , Spain , Temperature
14.
Rev Biol Trop ; 60(2): 567-76, 2012 Jun.
Article in English | MEDLINE | ID: mdl-23894929

ABSTRACT

Infectious diseases especially those caused by bacterial and viral pathogens are serious loss factors in shrimp farming. In this study, bacteria were isolated from the gut and hepatopancreas of stressed shrimps obtained from a commercial farm. The isolates were screened on Thiosulfate citrate bile salt sucrose (TCBS) agar plates for the selection of Vibrio species. Presumptive vibrios were characterized through tests for hemolytic and enzymatic activity, hydrophobicity, growth and molecular identification. Three experimental infections were conducted in order to confirm the pathogenicity of selected bacterial strains VHPC18, VHPC23, VHPC24 and VIC30. In the third experimental challenge the LD50 was obtained, it lasted 10 days with 10 shrimp, weighing 6.9+1. Ig, per tank. The treatments in triplicate were: (1) saline solution (control group); (2) 2xl0(5)CFU/shrimp; (3) 4xl05CFU/shrimp; (4) 2x10(6)CFU/shrimp; (5) 4x10(6)CFU/shrimp, and (6) 8x10(6)CFU/shrimp. In all challenges, water parameters measured during the experimental period remained within optimum ranges. Pathogenicity tests confirmed that the mixture of four vibrio isolates, identified as Vibrio sinaloensis, was virulent for L. vannamei. The LD50 value was 1.178x10(5)CFU/g body weight. V sinaloensis may act as opportunistic pathogens for cultured L. vannamei.


Subject(s)
Penaeidae/microbiology , Vibrio/classification , Animals , Aquaculture , Hepatopancreas/microbiology , Intestines/microbiology , Vibrio/isolation & purification , Vibrio/pathogenicity
15.
Polymers (Basel) ; 13(11)2021 Jun 03.
Article in English | MEDLINE | ID: mdl-34204916

ABSTRACT

Many design scenarios of components made of polymer materials are concerned with notches as representative constructive details. The failure hazard assessment of these components using models based on the assumption of cracked components leads to over-conservative failure estimations. Among the different alternative approaches proposed that are based on the apparent fracture toughness, KcN is considered. In so doing, the current deterministic underlying concept must be replaced by a probabilistic one to take into account the variability observed in the failure results in order to ensure a reliable design. In this paper, an approach based on the critical distance principle is proposed for the failure assessment of notched EPOLAM 2025 CT samples with each different notch radii (ρ) including a probabilistic assessment of the failure prediction. First, each apparent fracture toughness is transformed into the equivalent fracture toughness for ρ=0 based on the critical distances theory. Then, once all results are normalized to the same basic conditions, a Weibull cumulative distribution function is fitted, allowing the probability of failure to be predicted for different notch radii. In this way, the total number of the specimens tested in the experimental campaign is reduced, whereas the reliability of the material characterization improves. Finally, the applicability of the proposed methodology is illustrated by an example using the own experimental campaign performed on EPOLAM 2025 CT specimens with different notch radii (ρ).

16.
Materials (Basel) ; 14(4)2021 Feb 03.
Article in English | MEDLINE | ID: mdl-33546339

ABSTRACT

Despite the increasing economic incentives and environmental advantages associated to their substitution, carbon-rich fossil fuels are expected to remain as the dominant worldwide source of energy through at least the next two decades and perhaps later. Therefore, both the control and reduction of CO2 emissions have become environmental issues of major concern and big challenges for the international scientific community. Among the proposed strategies to achieve these goals, conversion of CO2 by its reduction into high added value products, such as methane or syngas, has been widely agreed to be the most attractive from the environmental and economic points of view. In the present work, thermocatalytic reduction of CO2 with H2 was studied over a nanostructured ceria-supported nickel catalyst. Ceria nanocubes were employed as support, while the nickel phase was supported by means a surfactant-free controlled chemical precipitation method. The resulting nanocatalyst was characterized in terms of its physicochemical properties, with special attention paid to both surface basicity and reducibility. The nanocatalyst was studied during CO2 reduction by means of Near Ambient Pressure X-ray Photoelectron Spectroscopy (NAP-XPS). Two different catalytic behaviors were observed depending on the reaction temperature. At low temperature, with both Ce and Ni in an oxidized state, CH4 formation was observed, whereas at high temperature above 500 °C, the reverse water gas shift reaction became dominant, with CO and H2O being the main products. NAP-XPS was revealed as a powerful tool to study the behavior of this nanostructured catalyst under reaction conditions.

17.
PeerJ ; 9: e10911, 2021.
Article in English | MEDLINE | ID: mdl-33665032

ABSTRACT

Host-microbe interactions play crucial roles in marine ecosystems. However, we still have very little understanding of the mechanisms that govern these relationships, the evolutionary processes that shape them, and their ecological consequences. The holobiont concept is a renewed paradigm in biology that can help to describe and understand these complex systems. It posits that a host and its associated microbiota with which it interacts, form a holobiont, and have to be studied together as a coherent biological and functional unit to understand its biology, ecology, and evolution. Here we discuss critical concepts and opportunities in marine holobiont research and identify key challenges in the field. We highlight the potential economic, sociological, and environmental impacts of the holobiont concept in marine biological, evolutionary, and environmental sciences. Given the connectivity and the unexplored biodiversity specific to marine ecosystems, a deeper understanding of such complex systems requires further technological and conceptual advances, e.g., the development of controlled experimental model systems for holobionts from all major lineages and the modeling of (info)chemical-mediated interactions between organisms. Here we propose that one significant challenge is to bridge cross-disciplinary research on tractable model systems in order to address key ecological and evolutionary questions. This first step is crucial to decipher the main drivers of the dynamics and evolution of holobionts and to account for the holobiont concept in applied areas, such as the conservation, management, and exploitation of marine ecosystems and resources, where practical solutions to predict and mitigate the impact of human activities are more important than ever.

18.
Antonie Van Leeuwenhoek ; 97(2): 207-10, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19921544

ABSTRACT

Vibrio species isolated from diseased seahorses were characterized by PCR amplification of repetitive bacterial DNA elements (rep-PCR) and identified by 16S ribosomal RNA gene sequence analysis. The results demonstrated that Vibrio alginolyticus and Vibrio splendidus were predominant in the lesions of these seahorses. To our knowledge, this is the first time that these bacterial species have been associated with disease symptoms in captive-bred seahorses.


Subject(s)
Smegmamorpha/microbiology , Vibrio Infections/veterinary , Vibrio/classification , Vibrio/isolation & purification , Animals , Cluster Analysis , DNA Fingerprinting , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Interspersed Repetitive Sequences , Molecular Sequence Data , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Vibrio Infections/microbiology
19.
Materials (Basel) ; 13(12)2020 Jun 23.
Article in English | MEDLINE | ID: mdl-32585877

ABSTRACT

Three nanostructured catalysts with low total rare earth elements (REEs) content (i.e., 15 mol.%) were prepared by depositing CeO2 or Ln3+-doped CeO2 (Ln3+ = Y3+ or La3+; Ln/Ce = 0.15) on the surface of ZrO2 nanoparticles, as nanometre-thick, fluorite-type clusters. These samples were subjected to successive reduction treatments at increasing temperatures, from 500 to 900 °C. A characterisation study by XPS was performed to clarify the diffusion process of cerium into the bulk of ZrO2 crystallites upon reduction to yield CexZr1-xO2-δ surface phases, and the influence of the incorporation of non-reducible trivalent REE cations, with sizes smaller (Y3+) and larger (La3+) than Ce4+ and Ce3+. For all nanocatalysts, a reduction treatment at a minimum temperature of 900 °C was required to accomplish a significant cerium diffusion. Notwithstanding, the size of the dopant noticeably affected the extent of this diffusion process. As compared to the undoped ZrO2-CeO2 sample, Y3+ incorporation slightly hindered the cerium diffusion, while the opposite effect was found for the La3+-doped nanocatalyst. Furthermore, such differences in cerium diffusion led to changes in the surface and nanostructural features of the oxides, which were tentatively correlated with the redox response of the thermally aged samples.

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