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The receptor-like kinases (RLKs) CLAVATA1 (CLV1) and BARELY ANY MERISTEMs (BAM1-BAM3) form the CLV1 family (CLV1f), which perceives peptides of the CLV3/EMBRYO SURROUNDING REGION (ESR)-related (CLE) family within various signaling pathways of Arabidopsis thaliana. CLE peptide signaling, which is required for meristem size control, vascular development, and pathogen responses, involves the formation of receptor complexes at the plasma membrane. These complexes comprise RLKs and co-receptors in varying compositions depending on the signaling context, and regulate expression of target genes, such as WUSCHEL (WUS). How the CLE signal is transmitted intracellularly after perception at the plasma membrane is not known in detail. Here, we found that the membrane-associated receptor-like cytoplasmic kinase (RLCK) MAZZA (MAZ) and additional members of the Pti1-like protein family interact in vivo with CLV1f receptors. MAZ, which is widely expressed throughout the plant, localizes to the plasma membrane via post-translational palmitoylation, potentially enabling stimulus-triggered protein re-localization. We identified a role for a CLV1-MAZ signaling module during stomatal and root development, and redundancy could potentially mask other phenotypes of maz mutants. We propose that MAZ, and related RLCKs, mediate CLV1f signaling in a variety of developmental contexts, paving the way towards understanding the intracellular processes after CLE peptide perception.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Meristema/genética , Meristema/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismoRESUMEN
Abundant studies have been published evaluating different parameters of reverse-phase liquid chromatography (LC) and supercritical fluid chromatography (SFC), both coupled to electrospray (ESI)/mass spectrometry (MS) for pesticide residue analysis. However, there is a lack of a comprehensive comparative study that facilitates deep knowledge about the benefits of using each technique. In the present study, the same mass spectrometer was used coupled to both liquid and supercritical fluid chromatographies with a multiresidue method of 215 compounds, for the analysis of pesticide residues in food samples. Through the injection of the spiked extracts, separate experiments were conducted. A study of the optimum ion source temperature using the different chromatography modes was performed. The results were evaluated in terms of sensitivity with tomato, leek, onion, and orange as representative fruit and vegetable matrices. The compounds which reported the highest area values in each chromatography were evaluated through their substance groups and polarity values. The impact of matrix effects obtained in tomato matrix was similar for both cases; however, SFC clearly showed better results in analyzing matrices with a higher number of natural co-extracted compounds. This can be explained by the combination of two effects: (i) chromatography separation and (ii) ion source efficiency. The chromatographic elution presented different profiles of matrix components, which had diverse impact on the coelution with the analytes, being more beneficial when SFC was used in the matrices studied. The data showed that the best results obtained in SFC are also related to a higher ionization efficiency even when the ESI emitter tip was not optimized for SFC flow. In the present study a comprehensive evaluation of the benefits and drawbacks of these chromatography modes for routine pesticide residue analysis related to target compounds/commodities is provided.
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Cromatografía Liquida/métodos , Cromatografía con Fluido Supercrítico/métodos , Residuos de Plaguicidas/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Residuos de Plaguicidas/normas , Estándares de ReferenciaRESUMEN
XBAT35 belongs to a subfamily of Arabidopsis (Arabidopsis thaliana) RING-type E3s that are similar in domain architecture to the rice (Oryza sativa) XA21 Binding Protein3, a defense protein. The XBAT35 transcript undergoes alternative splicing to produce two protein isoforms, XBAT35.1 and XBAT35.2. Here, we demonstrate that XBAT35.2 localizes predominantly to the Golgi and is involved in cell death induction and pathogen response. XBAT35.2, but not XBAT35.1, was found to trigger cell death when overexpressed in tobacco (Nicotiana benthamiana) leaves and does so in a manner that requires its RING domain. Loss of XBAT35 gene function disrupts the plant's ability to defend against pathogen attack, whereas overexpression of XBAT35.2 enhances resistance to pathogens. XBAT35.2 was found to be unstable and promotes its own degradation, suggesting self-regulation. Inoculation with virulent and avirulent strains of the bacterial pathogen Pseudomonas syringae pv tomato DC3000 results in a drastic reduction in the levels of ubiquitinated XBAT35.2 and an increase in the abundance of the E3. This implies that pathogen infection prohibits XBAT35.2 self-regulation and stabilizes the E3. In agreement with a role in defending against pathogens, XBAT35.2 interacts with defense-related Accelerated Cell Death11 (ACD11) in planta and promotes the proteasome-dependent turnover of ACD11 in cell-free degradation assays. In accordance with regulation by a stabilized XBAT35.2, the levels of ubiquitinated ACD11 increased considerably, and the abundance of ACD11 was reduced following pathogen infection. In addition, treatment of transgenic seedlings with a proteasome inhibitor results in the accumulation of ACD11, confirming proteasome-dependent degradation. Collectively, these results highlight a novel role for XBAT35.2 in cell death induction and defense against pathogens.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/citología , Arabidopsis/microbiología , Pseudomonas syringae/fisiología , Ubiquitina-Proteína Ligasas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Muerte Celular , Resistencia a la Enfermedad , Aparato de Golgi/metabolismo , Células Vegetales/metabolismo , Enfermedades de las Plantas/microbiología , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente , Complejo de la Endopetidasa Proteasomal/metabolismo , Unión Proteica , Proteolisis , Pseudomonas syringae/patogenicidad , Dominios RING Finger , Fracciones Subcelulares/metabolismo , Nicotiana/citología , Nicotiana/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación , VirulenciaRESUMEN
The aim of the study is to evaluate demographics, epidemiology, clinical characteristics, treatment and outcomes of Clostridium difficile infection (CDI) in patients with and without concurrent cancer. This is a prospective cohort study of consecutive primary CDI episodes in adults (January 2006-December 2016). CDI was diagnosed on the presence of diarrhoea and positive stool testing for toxigenic C. difficile. Univariate analysis assessed differences between cancer and non-cancer patients. Risk factors of all-cause 30-day mortality were determinate using the logistic multivariable procedure. In total, 787 CDI episodes were recorded, 191 in cancer patients (median age 64, IQR 50-73). Of these, 120 (63%) had solid and 71 (37%) haematological malignancies (24 received a stem cell transplant). At the CDI diagnosis, 158 (82.7%) cancer patients had prior antibiotics and 150 (78.5%) were receiving proton pump inhibitors. Fifty-seven (80.3%) patients with haematological and 52 (43.3%) with solid malignancies were under chemotherapy at diagnosis; 25 (35.2%) with haematological and 11 (9.2%) with solid malignancies had an absolute neutrophil count < 1000/mm3. Overall, 30-day mortality was higher in cancer patients than in those without (19.2 vs. 8.6% respectively, p < 0.001); recurrence rates did not vary significantly (11.1 vs. 11%, p = 0.936). By type of neoplasm, 30-day mortality was higher in patients with haematological malignancies and solid tumours than in patients without cancer (respectively, 25.4 vs. 8.6%; p < 0.001 and 15 vs. 8.6%; p < 0.001). Our results suggest that the prognosis of CDI (30-day mortality) is poorer in patients with cancer than in those without although percentages of recurrent infection are similar in these two patient populations.
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Clostridioides difficile , Infecciones por Clostridium/epidemiología , Infecciones por Clostridium/etiología , Enfermedades Hematológicas/complicaciones , Enfermedades Hematológicas/epidemiología , Neoplasias/complicaciones , Neoplasias/epidemiología , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Biomarcadores , Infecciones por Clostridium/diagnóstico , Infecciones por Clostridium/mortalidad , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , PronósticoRESUMEN
Thermally labile pesticides (captafol, captan, dicofol, and folpet) are highly prone to suffer thermal degradation during sample introduction into a gas chromatograph (GC) to tetrahydrophthalimide (THPI), 4,4'-dichlorobenzophenone (DCBP), and phthalimide (PI), respectively, mainly produced in the glass liner of the injector. This undesired behavior leads to inaccurate qualitative and quantitative results. Direct on-column injection (OCI) technique is evaluated as an alternative to avoid or minimize compound alteration during the analysis. This configuration was studied and evaluated for the determination of this group of thermally troublesome pesticides. The OCI inlet was operated in "track oven" temperature and connected to a wide-bore deactivated guard column that is itself connected to a capillary GC analytical column. This technique has demonstrated to be useful for avoiding degradation generated in the hot inlet. Limitations observed for OCI in routine analysis were injection volume, guard column length, and maintenance issues. Analytical standards spiked in vegetable solutions were injected in OCI, not observing any thermal degradation rate. On the contrary, classical splitless injection (SLI) produced high degradation rates in all cases. This OCI approach was validated in citrate QuEChERS extracts of tomato, apple, and orange matrices for these four compounds and their corresponding transformation products (THPI, DCBP, and PI), evaluating recoveries, repeatability, linearity, and matrix effect. This set-up enabled the correct identification and quantitation for most compounds at LOQs of 0.010 mg/kg in fruit and vegetable samples. The OCI grants evident differentiation between metabolites naturally occurring in food and thermal degradation products created during the analysis. Graphical abstract á .
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Cromatografía de Gases/métodos , Frutas/química , Plaguicidas/análisis , Verduras/química , Benzofenonas/química , Captano/química , Límite de Detección , Ftalimidas/química , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , TemperaturaRESUMEN
OBJECTIVE: Describe secular trends in the epidemiology and outcome of Clostridium difficile infection (CDI) at a tertiary hospital. METHODS: All consecutive primary CDI episodes in adults (January 2006-December 2015) were included. CDI was diagnosed on the presence of diarrhoea and a positive stool test for C. difficile toxin A and/or B. To define trends, a time-series analysis was performed using yearly data on demographics, clinical characteristics, management, antimicrobial treatment, and outcome of CDI. Patients were followed-up for three months after the diagnosis. RESULTS: There were 724 CDI episodes. Over the period from 2006 to 2015, the incidence rose from 0.18 episodes/1000 admissions to 0.26 episodes (relative rate [RR] 1.43; 95%CI, 1.02-2.00; Pâ¯=â¯0.035). Median Charlson comorbidity index increased from 2 (IQR 1-3) to 4 (IQR 2-4) (RR 1.65; 95%CI, 1.12-2.41; Pâ¯=â¯0.005). Overall, 80.4% of patients received proton pump inhibitors (PPIs) prior to CDI, and the percentage of PPI discontinuations rose from 2.3% to 20.4% (RR 8.80; 95%CI 1.20-64.36; Pâ¯=â¯0.006). Management of non-Clostridium antibiotics also changed: antibiotic withdrawals or switches increased from 4.2% to 29.2% (RR 7.00; 95%CI 1.68-29.15, Pâ¯=â¯0.001). Regarding CDI treatment, the percentage of patients treated with metronidazole decreased (88.9% vs 52.6%) (RR 0.59 (0.48-0.73), Pâ¯<â¯0.001), whereas the percentage receiving vancomycin increased (1.9% vs 32.6%) (RR 17.62 (2.47-125.49), Pâ¯<â¯0.001). The percentages of cures, deaths, and first recurrences did not significantly change over the 10-year period. CONCLUSIONS: Changes in CDI management were associated with a stable prognosis (percentage of cures and first recurrences), even though affected patients had a greater number of comorbidities over time.
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Clostridioides difficile/aislamiento & purificación , Infecciones por Clostridium/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Técnicas Bacteriológicas , Infecciones por Clostridium/tratamiento farmacológico , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , España/epidemiología , Centros de Atención Terciaria , Resultado del Tratamiento , Adulto JovenRESUMEN
Brochothrix thermosphacta is the predominant spoilage microorganism in meat and its control in processing environments is important to maintain meat product quality. Atmospheric cold plasma is of interest for control of pathogenic and spoilage microorganisms in foods. This study ascertained the potential of dielectric barrier discharge atmospheric cold plasma (DBD-ACP) for control of B. thermosphacta, taking microbial and food environment factors into consideration, and investigated the shelf-life of lamb chop after in-package plasma treatment in modified atmosphere. Community profiling was used to assess the treatment effects on the lamb microflora. ACP treatment (80 kV) for 30s inactivated B. thermosphacta populations below detection levels in PBS, while 5 min treatment achieved a 2 Log cycle reduction using a complex meat model medium and attached cells. The antimicrobial efficacy of plasma was reduced but still apparent on lamb chop surface-inoculated with high concentrations of B. thermosphacta. Lamb chop treated under modified atmosphere exhibited reduced microbial growth over the product shelf-life and community profiling showed no evident changes to the microbial populations after the treatment. The overall results indicated potential of ACP to enhance microbial control leading to meat storage life extension through adjusting the modality of treatment.
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Brochothrix/efectos de los fármacos , Embalaje de Alimentos/métodos , Conservación de Alimentos/métodos , Carne/microbiología , Gases em Plasma/farmacología , Animales , Brochothrix/crecimiento & desarrollo , Contaminación de Alimentos/análisis , Contaminación de Alimentos/prevención & control , Embalaje de Alimentos/instrumentación , Conservación de Alimentos/instrumentaciónRESUMEN
Two antimicrobial coatings, namely Sodium octanoate and Auranta FV (a commercial antimicrobial composed of bioflavonoids, citric, malic, lactic, and caprylic acids) were used. These two antimicrobials were surface coated onto the inner polyethylene layer of cold plasma treated polyamide films using beef gelatin as a carrier and coating polymer. This packaging material was then used to vacuum pack beef sub-primal cuts and stored at 4 °C. A control was prepared using the non-coated commercial laminate and the same vacuum packaged sub-primal beef cuts. During storage, microbial and quality assessments were carried out. Sodium octanoate treated packages significantly (p < 0.05) reduced microbial counts for all bacteria tested with an increase of 7 and 14 days, respectively compared to control samples. No significant effect on pH was observed with any treatment. The results suggested that these food grade antimicrobials have the potential to be used in antimicrobial active packaging applications for beef products.
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Antiinfecciosos/química , Embalaje de Alimentos/métodos , Conservación de Alimentos , Plásticos , Animales , Bacterias/crecimiento & desarrollo , Bacterias/aislamiento & purificación , Caprilatos/análisis , Caprilatos/química , Bovinos , Recuento de Colonia Microbiana , Microbiología de Alimentos , Almacenamiento de Alimentos/métodos , Gelatina/análisis , Gelatina/química , Gases em Plasma/química , Carne Roja/microbiología , VacioRESUMEN
Venous catheter-related infections are a problem of particular importance, due to their frequency, morbidity and mortality, and because they are potentially preventable clinical processes. At present, the majority of hospitalized patients and a considerable number of outpatients are carriers of these devices. There has been a remarkable growth of knowledge of the epidemiology of these infections, the most appropriate methodology for diagnosis, the therapeutic and, in particular, the preventive strategies. Multimodal strategies, including educational programs directed at staff and a bundle of simple measures for implementation, applied to high-risk patients have demonstrated great effectiveness for their prevention. In this review the epidemiology, the diagnosis, and the therapeutic and preventive aspects of these infections are updated.
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Infecciones Relacionadas con Catéteres/etiología , Cateterismo Venoso Central/efectos adversos , Cateterismo Periférico/efectos adversos , Flebitis/etiología , Algoritmos , Antiinfecciosos/uso terapéutico , Infecciones Relacionadas con Catéteres/diagnóstico , Infecciones Relacionadas con Catéteres/epidemiología , Infecciones Relacionadas con Catéteres/terapia , Infección Hospitalaria/etiología , Infección Hospitalaria/prevención & control , Infección Hospitalaria/terapia , Remoción de Dispositivos , Farmacorresistencia Microbiana , Contaminación de Equipos , Humanos , Huésped Inmunocomprometido , Flebitis/diagnóstico , Flebitis/terapia , Factores de Riesgo , Piel/microbiología , España/epidemiologíaRESUMEN
The analysis of pesticide residues and mycotoxins in baby food demands exceptionally low limits of quantitation, necessitating the use of highly sensitive instruments capable of conducting trace analyses. High-resolution instruments typically fail to detect such low levels. However, the latest advancements in liquid time-of-flight technology, when coupled with ion trapping, enable ion enrichment, thereby improving detection levels. This allows for the analysis of these substances at low concentration levels, benefiting from enhanced mass accuracy. Additionally, the use of mass accuracy data helped eliminate matrix interferences, thereby enabling high-confidence identification. We developed a multi-residue method to analyse 219 pesticide residues and 9 mycotoxin residues in baby food matrices. Utilizing a QuEChERS-based extraction method, the samples were then analysed using an LC-ZenoTOF 7600 system with mass window screening acquisition. For pesticides, the limit of quantitation was 0.001-0.003 mg/kg for 81 % of the evaluated compounds, 0.005 mg/kg for 13 %, 0.010 mg/kg for 4 % and 0.020-0.030 for 2 %; good linearities were obtained at these levels. Apparent recoveries were evaluated at 0.003, 0.005, and 0.010 mg/kg. At the lowest recovery level, 93 % of compounds showed recoveries between 70 and 120 %. The rest of the compounds were in the range of 63-129 %, with relative standard deviation values below 20 %. For mycotoxins, the limits of quantitation ranged from 0.0001 to 0.100 mg/kg, with matrix-matched concentrations assessed within this range. Recoveries were evaluated at low concentration range (0.001-0.003 mg/kg) and high range (0.020-0.050) with apparent recoveries values between 92 and 140 %. Finally, a total of 31 commercial baby food samples were analysed using this method. The results indicated that 16 samples contained pesticide residues, while two samples were found to have mycotoxins.
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Contaminación de Alimentos , Alimentos Infantiles , Micotoxinas , Residuos de Plaguicidas , Micotoxinas/análisis , Residuos de Plaguicidas/análisis , Alimentos Infantiles/análisis , Contaminación de Alimentos/análisis , Espectrometría de Masas/métodos , Humanos , Límite de Detección , LactanteRESUMEN
In this comprehensive study, we evaluated the feasibility of using hydrogen instead of helium as a carrier gas in a GC-MS/MS system for pesticide residue analysis, spanning three matrices: pepper, tomato, and zucchini. Initial assessments focused on the ion source's chemical inertness, employing nitrobenzene as a benchmark to monitor the hydrogenation process. A method with a duration of less than 12 minutes was developed, achieving good chromatographic peak resolution attributable to the enhanced chromatographic performance of hydrogen as a carrier gas. The study emphasized the optimization of system parameters, testing various ion source temperatures, detector voltages, and injection volumes. Sensitivity assessments, based on the DG-SANTE criteria, indicated that the majority of compounds were identifiable at a concentration of 5 µg kg-1 (81% in tomato, 84% in pepper and 73% in zucchini). Detailed validation for reproducibility, matrix effects, and linearity across 150 pesticides unveiled generally favorable outcomes, with a notable majority of compounds displaying low matrix effects, satisfactory linearity ranges and good reproducibility with most compounds returning a relative standard deviation (RSD) below 10%. When applied to 15 real samples, the hydrogen-based system's performance was juxtaposed against a helium-based counterpart, revealing that results are very comparable between both systems. This comparative approach highlights hydrogen's potential as a reliable and efficient carrier gas in pesticide residue analysis for routine food control laboratories, overcoming difficulties resulting from the lack of helium supplies.
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Residuos de Plaguicidas , Plaguicidas , Espectrometría de Masas en Tándem/métodos , Frutas/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Verduras/química , Plaguicidas/análisis , Helio/análisis , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/química , Reproducibilidad de los Resultados , Hidrógeno/análisisRESUMEN
Renal cell carcinoma (RCC) is a kidney neoplasm that accounts for 85% of cases and has complex genetic pathways that affect its development and progression. RCC metastasis can occur in 20%-50% of patients and usually affects distant organs. Gastric metastases (GM) from RCC are rare and present as polyp-like growths in the submucosal layer, accounting for 0.2%-0.7% of cases. This case report describes an 84-year-old female with Furhman grade II ccRCC who presented with an atherothrombotic ischemic stroke and gastrointestinal bleeding nine years post-radical nephrectomy. Gastroscopy revealed a 12mm pseudopedicled gastric lesion with ulceration and bleeding, diagnosed as metastatic ccRCC. The discussion focuses on the rarity, diagnostic challenges, and prognostic elements of gastric metastasis from RCC. The median survival after detecting digestive metastasis varies widely, and the mechanisms include direct invasion and dissemination through lymphatic, transcelomic, or hematogenous routes. Prognostic markers encompass patient history, symptoms, time since RCC diagnosis, overall health, and genetic factors. Surgical removal of gastric lesions and targeted therapy are treatment options that can improve survival. This case report highlights the need for further research to enhance diagnostic and treatment strategies for this rare aspect of RCC pathophysiology.
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BACKGROUND AND AIMS: Microscopic colitis [MC] is currently regarded as an inflammatory bowel disease that manifests as two subtypes: collagenous colitis [CC] and lymphocytic colitis [LC]. Whether these represent a clinical continuum or distinct entities is, however, an open question. Genetic investigations may contribute important insight into their respective pathophysiologies. METHODS: We conducted a genome-wide association study [GWAS] meta-analysis in 1498 CC, 373 LC patients, and 13 487 controls from Europe and the USA, combined with publicly available MC GWAS data from UK Biobank and FinnGen [2599 MC cases and 552 343 controls in total]. Human leukocyte antigen [HLA] alleles and polymorphic residues were imputed and tested for association, including conditional analyses for the identification of key causative variants and residues. Genetic correlations with other traits and diagnoses were also studied. RESULTS: We detected strong HLA association with CC, and conditional analyses highlighted the DRB1*03:01 allele and its residues Y26, N77, and R74 as key to this association (best pâ =â 1.4â ×â 10-23, odds ratio [OR]â =â 1.96). Nominally significant genetic correlations were detected between CC and pneumonia [rgâ =â 0.77; pâ =â 0.048] and oesophageal diseases [rgâ =â 0.45, pâ =â 0.023]. An additional locus was identified in MC GWAS analyses near the CLEC16A and RMI2 genes on chromosome 16 [rs35099084, pâ =â 2.0â ×â 10-8, ORâ =â 1.31]. No significant association was detected for LC. CONCLUSION: Our results suggest CC and LC have distinct pathophysiological underpinnings, characterised by an HLA predisposing role only in CC. This challenges existing classifications, eventually calling for a re-evaluation of the utility of MC umbrella definitions.
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Colitis Colagenosa , Colitis Linfocítica , Colitis Microscópica , Humanos , Estudio de Asociación del Genoma Completo , Antígenos HLA/genética , Antígenos de Histocompatibilidad Clase II , Colitis Microscópica/genética , Colitis Linfocítica/genéticaRESUMEN
RATIONALE: Dendrimer nanocarriers have become of increasing interest in the field of biomedicine for their drug delivery potential. Surface modifications and optimized nanosize control are the strategies being followed to enhance drug delivery efficacy and renal clearance, especially for dendrimers of a lower generation number. The aim of this study was the development and performance evaluation of an analytical method for the quantitative determination of polyamidoamine (PAMAM) dendrimers in urine. METHODS: PAMAM dendrimers (generations G0 to G3) were analyzed using liquid chromatography/electrospray ionization hybrid quadrupole linear ion trap mass spectrometry (LC/ESI-QqLIT-MS). Quantitative analysis was performed in selected reaction monitoring (SRM) mode. To confer a higher degree of confidence on the identification of PAMAM dendrimers, an SRM scan and collision-induced dissociation (CID), as a dependent scan, were performed in one single run using the information-dependent acquisition (IDA) mode. RESULTS: The LC/ESI-QqLIT-MS method, in SRM mode, allowed quantitative determination in urine matrix with good repeatability and reproducibility (relative standard deviation (R.S.D.) from 2 to 15%), linearity (R >0.99) over the concentration range (6â10-4 to 5â10-2 mmol.L-1 ), and sensitivity within the micromolar range. The detection limit values were above 1â10-4 mmol.L-1 in both solvent and urine, for the generations studied. CONCLUSIONS: The developed method has demonstrated a capability for the identification and quantification of PAMAM dendrimer nanoparticles in a complex liquid matrix. The use of an LC/ESI-QqLIT-MS system, of modest m/z range and unit resolution, offers an alternative in the analysis of lower generation PAMAM dendrimers between mass analyzers of higher resolution and the conventional LC-UV method that is commonly applied for dendrimer quantification, but which lacks sufficient identification capacity. Copyright © 2013 John Wiley & Sons, Ltd.
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Clean-up step is essential during the multiresidue sample preparation process to remove undesired matrix components that may cause analytical interferences or suppression effect. However, its application generally by specific sorbents entails time-consuming work producing low recoveries for some compounds. Moreover, it usually needs to be adapted to the different co-extractives from the matrix present in the samples by using different chemical sorbents increasing the number of validation procedures. Therefore, the development of a more efficient and automated and unified clean-up procedure means a significant time reduction and laboratory work with improved performance. In this study, extracts from different matrices (tomato, orange, rice, avocado and black tea) were purified by manual dispersive clean-up (different procedures according to the matrix group) in parallel with an automated µSPE clean-up workflow, in both cases based on QuEChERS extraction. The latter procedure employed clean-up cartridges containing a mixture of sorbent materials (anhydrous MgSO4/PSA/C18/CarbonX) suitable for multiple matrices. All the samples were analysed by liquid chromatography mass spectrometry and the results obtained from both procedures have been compared in terms of the extract cleanness, performance, interferences, and sample workflow. At the levels studied, similar recoveries were achieved by both techniques (manual and automated) except for reactive compounds when PSA was used as the sorbent material producing low recoveries. However, the µSPE recoveries were between 70-120%. Furthermore, closer calibration line slopes were provided when µSPE was applied to the different matrix groups studied. It is important to note that up to 30% more samples per day can be analysed using an automated µSPE compared to the manual method (which requires shaking, centrifuging, then taking the supernatant and adding formic acid in ACN); it also provides good repeatability - an RSD (%) < 10%. Consequently, this technique is a very useful option for routine analyses, greatly simplifying the work of muti-residue methods.
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Residuos de Plaguicidas , Plaguicidas , Humanos , Masculino , Plaguicidas/análisis , Residuos de Plaguicidas/análisis , Espectrometría de Masas en Tándem/métodos , Antígeno Prostático Específico/análisis , Cromatografía Liquida/métodos , Extracción en Fase Sólida/métodosRESUMEN
Introduction: In recent years, job crafting has greatly interested Work and Organizational Psychology. Different research studies have shown its positive impact on people and organizational performance. However, it knows little about the differential effect of the two dimensions that make up this variable (prevention-focused and promotion-focused) and its role in the health-impairment spiral process of the job demand-resources theory (JD-R). Method: This research aims to analyze the mediating effect of the different dimensions of job crafting on the influence of burnout on performance and self-efficacy in the workplace. The study used a sample of 339 administrative employees of a university. Results: The results indicate that promotion-focused job crafting is a mediating variable in the relationship between the influence of burnout on performance and self-efficacy. Unexpectedly, prevention-focused job crafting does not have this mediating role in the same relationship. Discussion: These findings confirm the adverse impact of burnout on personal and organizational improvement, while showing the absence of prevention/protection responses of employees when they are burned out. The theoretical and practical implications show an advance in knowledge about the process of health deterioration and about the spiral of health deterioration in the JD-R theory.
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Background and objective: The objective was to describe the clinical characteristics and prognosis of patients with nosocomial SARS-CoV-2 infection. Methods: An observational and prospective study was performed in a referral hospital. We included all adult patients diagnosed with nosocomial SARS-CoV-2 infection in October 2020. Nosocomial infection was defined as a negative PCR for SARS-CoV-2 on admission and a positive PCR after 7 days of hospitalization. Results: We included 66 cases of nosocomial SARS-CoV-2 infection: 39 (59%) men, median age at diagnosis was 74.5 years (IQR 56.8-83.1) and median Charlson comorbidity index was 3 points (IQR 1-5). Twenty-seven (41%) developed pneumonia and 13 (20%) died during admission. Mortality at 28 days was 33% (22 patients). Mortality at 28 days in the 242 patients with community-acquired SARS-CoV-2 infection who were hospitalized during the same period was 10%. Conclusions: Preventive measures and early detection of nosocomial outbreaks of COVID-19 should be prioritized to minimize the negative impact of this infection.
Antecedentes y Objetivo: El objetivo fue describir las características clínicas y el pronóstico de los pacientes con infección nosocomial por SARS-CoV-2. Métodos: Se realizó un estudio observacional y prospectivo en un hospital de referencia. Se incluyeron todos los pacientes adultos diagnosticados de infección por SARS-CoV-2 nosocomial en octubre de 2020, definida como una PCR para SARS-CoV-2 negativa al ingreso y positiva a partir de los siete días de hospitalización. Resultados: Se diagnosticaron 66 casos de infección por SARS-CoV-2 nosocomial: 39 (59%) hombres, edad mediana al diagnóstico de 74,5 años (RIC 56,8-83,1) y mediana del índice de comorbilidad de Charlson de 3 puntos (RIC 1−5). Veintisiete (41%) presentaron neumonía y 13 (20%) fallecieron durante el ingreso. La mortalidad a los 28 días fue del 33% (22 pacientes). La mortalidad a los 28 días en los 242 pacientes con infección por SARS-CoV-2 adquirida en la comunidad y hospitalizados durante el mismo periodo fue del 10%. Conclusiones: Se deben extremar las medidas de prevención y detección precoz de brotes nosocomiales de COVID-19 para minimizar el impacto negativo de esta infección.
RESUMEN
BACKGROUND AND OBJECTIVE: The objective was to describe the clinical characteristics and prognosis of patients with nosocomial SARS-CoV-2 infection. METHODS: An observational and prospective study was performed in a referral hospital. We included all adult patients diagnosed with nosocomial SARS-CoV-2 infection in October 2020. Nosocomial infection was defined as a negative PCR for SARS-CoV-2 on admission and a positive PCR after 7 days of hospitalization. RESULTS: We included 66 cases of nosocomial SARS-CoV-2 infection: 39 (59%) men, median age at diagnosis was 74.5 years (IQR 56.8-83.1) and median Charlson comorbidity index was 3 points (IQR 1-5). Twenty-seven (41%) developed pneumonia and 13 (20%) died during admission. Mortality at 28 days was 33% (22 patients). Mortality at 28 days in the 242 patients with community-acquired SARS-CoV-2 infection who were hospitalized during the same period was 10%. CONCLUSIONS: Preventive measures and early detection of nosocomial outbreaks of COVID-19 should be prioritized to minimize the negative impact of this infection.
Asunto(s)
COVID-19 , Infección Hospitalaria , Adulto , COVID-19/epidemiología , Infección Hospitalaria/diagnóstico , Infección Hospitalaria/epidemiología , Femenino , Hospitales , Humanos , Masculino , Estudios Prospectivos , Derivación y Consulta , SARS-CoV-2RESUMEN
The aim of this work was to study the effect of olive powder combined with high hydrostatic pressure (HHP) on the inactivation of Bacillus cereus spores, to use it as an additional control hurdle in beverages pasteurised by this technology. With this purpose, reference medium prepared at different concentrations of olive powder was inoculated with B. cereus spores and subjected to different pressure treatments. The outgrowth capacity of the treated spores was then determined at 20°C and 32°C. The addition of olive powder was found to slightly reduce the effectiveness of HHP, although in post-treatment storage there was an increased bacteriostatic effect in the samples with 2.5% of olive powder at both temperatures in the samples pressurised at 400 and 500 MPa, and only at 20°C in the samples pressurised at 200 MPa. The addition of olive powder therefore had an additive effect with storage temperature and HHP processing and could act as an additional control hurdle during the shelf-life of products pasteurised by HHP technologies or in the case of cold-chain breakage.