Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 196
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Nature ; 532(7597): 73-6, 2016 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-27078566

RESUMEN

The signature of (60)Fe in deep-sea crusts indicates that one or more supernovae exploded in the solar neighbourhood about 2.2 million years ago. Recent isotopic analysis is consistent with a core-collapse or electron-capture supernova that occurred 60 to 130 parsecs from the Sun. Moreover, peculiarities in the cosmic ray spectrum point to a nearby supernova about two million years ago. The Local Bubble of hot, diffuse plasma, in which the Solar System is embedded, originated from 14 to 20 supernovae within a moving group, whose surviving members are now in the Scorpius-Centaurus stellar association. Here we report calculations of the most probable trajectories and masses of the supernova progenitors, and hence their explosion times and sites. The (60)Fe signal arises from two supernovae at distances between 90 and 100 parsecs. The closest occurred 2.3 million years ago at present-day galactic coordinates l = 327°, b = 11°, and the second-closest exploded about 1.5 million years ago at l = 343°, b = 25°, with masses of 9.2 and 8.8 times the solar mass, respectively. The remaining supernovae, which formed the Local Bubble, contribute to a smaller extent because they happened at larger distances and longer ago ((60)Fe has a half-life of 2.6 million years). There are uncertainties relating to the nucleosynthesis yields and the loss of (60)Fe during transport, but they do not influence the relative distribution of (60)Fe in the crust layers, and therefore our model reproduces the measured relative abundances very well.

2.
Lett Appl Microbiol ; 75(2): 401-409, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35587396

RESUMEN

Dermal replacement materials bioactivated with cyanobacteria have shown promising potential for wound regeneration. To date, extraction of cyanobacteria RNA from seeded scaffolds has not been described. The aim of this study was to develop a method to isolate total RNA from bioactivated scaffolds and to propose a new approach in determining living bacteria based on real-time PCR. Transgenic Synechococcus sp. PCC 7002 (tSyn7002) were seeded in liquid cultures or scaffolds for dermal regeneration in vitro and in vivo for 7 days. RNA was extracted with a 260/280 ratio of ≥2. The small subunit of the 30S ribosome in prokaryotes (16S) and RNAse P protein (rnpA) were validated as reference transcripts for PCR analysis. Gene expression patterns differed in vitro and in vivo. Expression of 16S was significantly upregulated in scaffolds in vitro, as compared to liquid cultures, whilst rnpA expression was comparable. In vivo, both 16S and rnpA showed reduced expression compared to in vitro (16S: in vivo Ct value 13.21 ± 0.32, in vitro 12.44 ± 0.42; rnpA in vivo Ct value 19.87 ± 0.41, in vitro 17.75 ± 1.41). Overall, the results demonstrate rnpA and 16S expression after 7 days of implantation in vitro and in vivo, proving the presence of living bacteria embedded in scaffolds using qPCR.


Asunto(s)
Ribonucleasa P , Synechococcus , Andamios del Tejido , Expresión Génica , ARN , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Ribonucleasa P/genética , Synechococcus/genética
3.
Lett Appl Microbiol ; 71(5): 490-497, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32777092

RESUMEN

The aim of this study was to synthesize and investigate the in vitro antifungal properties of 23 cinnamyl Schiff bases. In addition, cytotoxic effects of such cinnamyl Schiff bases against human lung, kidney or red blood cells were also checked. The compounds were synthesized in a single-step, 2 min of reaction under microwave irradiation produced up to 97% yield. Six of the 23 cinnamyl Schiff bases possessed antifungal activities against strains of Candida, Aspergillus, Fonsecaea and, particularly, Cryptococcus species. Indeed, cinnamyl Schiff bases 1 and 23 exhibited minimum inhibitory concentration (MIC) values more than twofold lower than fluconazole (FCZ) against all the Cryptococcus neoformans strains (MIC = 1·33, 1·4 and 5·2 µg ml-1 , respectively) and Cryptococcus gattii strains (MIC = 5·3, 2·8 and 9·2 µg ml-1 , respectively) (12 strains of each species) while cinnamyl Schiff base 11 was as potent as FCZ against all strains from both Cryptococcus species. No significant cytotoxic effects were observed for Schiff bases against human lung, kidney or red blood cells, all presenting selective indexes higher than 10. In conclusion, this study revealed cinnamyl Schiff bases, especially 1 and 23, as new lead anticryptococcal agents for the discovery of novel antifungal drugs. SIGNIFICANCE AND IMPACT OF THE STUDY: The occurrence and severity of fungal infections have increased in recent decades due to resistance to available antifungal drugs and the appearance of new emerging pathogens. Thus, the search for new antifungal agents is mandatory. From a series of 23 cinnamyl Schiff bases, two compounds (1 and 23) were interrogated as new anticryptococcal agents without significant cytotoxicity against human lung, kidney or red blood cells. In turns, these new Schiff bases are lead compounds for the discovery of novel antifungal drugs.


Asunto(s)
Antifúngicos/farmacología , Micosis/tratamiento farmacológico , Bases de Schiff/farmacología , Antifúngicos/síntesis química , Antineoplásicos/farmacología , Aspergillus/efectos de los fármacos , Candida/efectos de los fármacos , Cryptococcus gattii/efectos de los fármacos , Cryptococcus neoformans/efectos de los fármacos , Fluconazol/farmacología , Fonsecaea/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Bases de Schiff/síntesis química
4.
Clin Exp Allergy ; 46(3): 479-90, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26609909

RESUMEN

BACKGROUND: Several clinical and experimental studies have implicated IL-33 and its receptor ST2 in the development of asthma. However, the effect of IL-33/ST2 signalling on airway responses and inflammation in allergic asthma is not well established. OBJECTIVE: To investigate the role of IL-33/ST2 signalling in promoting allergen-induced airway hyperresponsiveness (AHR), airway inflammation, antigen-specific IgE production and mast cell activity in a mouse model of asthma. METHODS: ST2-deficient (ST2(-/-)) mice and control BALB/c mice were given house dust mite (HDM) extract over a 6-week period. Forty-eight hours after the final HDM administration, lung function and airway inflammation were evaluated. Airway responsiveness was determined in the central airways and peripheral lung. Cellular infiltration and mast cell protease mMCP-1 levels were quantified in bronchoalveolar lavage fluid (BALF). Recruitment of inflammatory cells and inflammatory cytokine profiles were assessed in pulmonary tissue, and HDM-specific IgE was measured in serum. RESULTS: ST2 deficiency diminished HDM-induced AHR in the peripheral lung, while AHR in the central airways was unaffected. Inflammatory responses to HDM were also reduced in ST2(-/-) mice as reflected by the lower induction of HDM-specific serum IgE, inhibition of HDM-induced eosinophilia and reduced macrophage count in BALF, and a diminished influx of inflammatory cells and reduced goblet cell hyperplasia around the peripheral airways. Furthermore, the levels of the inflammatory cytokines IL-1ß, IL-5, IL-13, IL-33, GM-CSF, thymic stromal lymphopoietin and mast cell protease mMCP-1 were reduced in HDM-treated ST2(-/-) mice compared with wild-type controls. CONCLUSIONS: In addition to promoting Th2 inflammation, we now suggest a role for the IL-33/ST2 pathway for the induction of peripheral inflammation and mucus production that causes AHR in the peripheral lung. This mechanism for inducing AHR at distal parts of the lung may be of specific importance as asthma is considered as a small airway disease.


Asunto(s)
Alérgenos/inmunología , Asma/inmunología , Asma/metabolismo , Proteína 1 Similar al Receptor de Interleucina-1/metabolismo , Pyroglyphidae/inmunología , Remodelación de las Vías Aéreas (Respiratorias) , Animales , Asma/genética , Asma/patología , Líquido del Lavado Bronquioalveolar/inmunología , Quimiocina CCL2/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Inmunización , Inmunoglobulina E/inmunología , Mediadores de Inflamación , Proteína 1 Similar al Receptor de Interleucina-1/genética , Interleucina-33/genética , Interleucina-33/metabolismo , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/patología , Mastocitos/inmunología , Mastocitos/metabolismo , Ratones , Ratones Noqueados , Transducción de Señal
5.
Klin Padiatr ; 228(3): 157-63, 2016 May.
Artículo en Alemán | MEDLINE | ID: mdl-27096304

RESUMEN

Cancer Related Fatigue (CRF) is known as one of the strongest and incriminating side effects of cancer for adults and children. By now there is a lack of valid assessments and sufficient therapy in pediatric oncology. For children it is a tough challenge to accept this overwhelming tiredness and lower activity level in their daily life routines. First positive effects in CFR therapy were found by adults, but this specific scientific field is very young and therefore mostly unexplored. 4 databases for medical and therapeutic journals were systematically searched for RCTs, CCTs and CTs. Systematic reviews were analyzed as well. All studies were carried out in pediatric oncology and deal with exercise therapy. The enclosed studies were valued by PEDro-Scale. Only a handful papers about a potential reduction of CRF in pediatrics could be found, one RCT, 2 CCTs and one CT. No additional results could be found. To summarize the 4 papers, it can be stated that the duration of intervention depends between 2 days and 12 weeks. Also there are differences between the option inpatient and outpatient programs, as well as with or without supervising. The exercise therapy mostly consists of strength and endurance training in combination with warm-up and cool-down programs. This review underlines the importance of developing new assessments. Especially bigger groups of participants should be analyzed with the scope on individualized, supervised program. So far, CRF is underestimated in pediatric oncology and it is very crucial to identify the symptoms. This could lead to an improvement in quality of life.


Asunto(s)
Terapia por Ejercicio , Fatiga/rehabilitación , Neoplasias/complicaciones , Neoplasias/rehabilitación , Niño , Alemania , Humanos , Evaluación de Procesos y Resultados en Atención de Salud
6.
Klin Padiatr ; 228(6-07): 313-318, 2016 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-27846661

RESUMEN

Background: Chemotherapy-induced peripheral neuropathy is a frequent side-effect of drugs that are used in the treatment of cancer. Affected individuals can suffer from motor, sensory or autonomy nerve damage. Further medication is used for the treatment of CIPN which can cause further side-effects. Patients should be offered physical therapy treatment to relieve the symptoms. Objective: The aim of this article is to give an overview of available literature investigating physical therapy in CIPN in pediatric oncology. Methods: To determine relevant literature, a systematic review was conducted in the databases CINAHL, The Cochrane Library, ERIC, MEDPILOT, PEDro, PsycARTICLES, PsycINFO, PubMed and DIMDI. Besides the methodological quality of the identified literature is supposed to be reviewed. Results: There is no current literature regarding the subject of this article, so no evaluation of the quality could be carried out. Although several publications concerning adults could be identified and transfer could be established for pediatrics. Conclusion: Acupuncture appeared to be effective in the treatment of CIPN in adults. Good results appeared especially regarding pain. Sensorimotor training, balance training, electrotherapy and alternative methods like Reiki and Yoga showed good results for patients symptoms. These treatment methods give a future prospect how CIPN in children can be treated successfully - but further pediatric research is necessary.


Asunto(s)
Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Enfermedades del Sistema Nervioso Periférico/rehabilitación , Modalidades de Fisioterapia , Terapia por Acupuntura , Niño , Humanos , Resultado del Tratamiento
7.
Phys Rev Lett ; 113(22): 221101, 2014 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-25494064

RESUMEN

We report the first direct measurement of the overall characteristics of microwave radio emission from extensive air showers. Using a trigger provided by the KASCADE-Grande air shower array, the signals of the microwave antennas of the Cosmic-Ray Observation via Microwave Emission experiment have been read out and searched for signatures of radio emission by high-energy air showers in the GHz frequency range. Microwave signals have been detected for more than 30 showers with energies above 3×10^{16} eV. The observations presented in this Letter are consistent with a mainly forward-directed and polarized emission process in the GHz frequency range. The measurements show that microwave radiation offers a new means of studying air showers at E≥10^{17} eV.

8.
Ann Surg Oncol ; 20 Suppl 3: S625-35, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23864307

RESUMEN

BACKGROUND: Alpha-fetoprotein (AFP)-secreting hepatocellular carcinomas (HCC) represent a genetically distinct subset of tumors often associated with a worse prognosis. However, the molecular mechanisms that underlie these phenotypic differences remain poorly understood. METHODS: HCC tumor samples from 27 patients were profiled using the Affymetrix 133 Plus 2.0 GeneChips. GeneGO Metacore software was used to identify altered biologic pathways. Expression validation was confirmed by RT-PCR. Manipulation of miR-675 by overexpression and antagomir-mediated knockdown was carried out with subsequent evaluation of effects on cell behavior by cell cycle, proliferation, invasion, and growth in soft agar assays. RESULTS: We identified a strong relationship between primary tumor H19 gene expression and elevated serum AFP. H19 has recently been identified to encode microRNA-675 (miR-675), and we confirmed the relationship in an independent sample of patients. Pathway analyses of the effect of miR-675 overexpression in hepatoma cells revealed a predominant upregulation of cell adhesion and cell cycle initiation pathways. We have demonstrated that miR-675 mediates increases in proliferation and an accumulation of cells with tetraploid DNA content associated with a repression of Rb. We also demonstrated that overexpression of miR-675 alters cellular morphology, reduces invasive potential, and increases anchorage-independent growth capacity. These findings are consistent with a mesenchymal-to-epithelial transition, associated with a reduction in the expression of the key EMT mediator, Twist1. CONCLUSIONS: Expression of the miR-675 in hepatocellular carcinoma links a dramatic upregulation of proliferative and growth capacity with inhibition of motility in HCC cells.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroARNs/genética , Proteínas Nucleares/metabolismo , Proteína de Retinoblastoma/metabolismo , Proteína 1 Relacionada con Twist/metabolismo , alfa-Fetoproteínas/metabolismo , Anciano , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Western Blotting , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Adhesión Celular , Movimiento Celular , Proliferación Celular , Transición Epitelial-Mesenquimal , Femenino , Perfilación de la Expresión Génica , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Luciferasas/metabolismo , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tasa de Supervivencia , Células Tumorales Cultivadas
9.
Haemophilia ; 19 Suppl 3: 1-18, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23383607

RESUMEN

The first meeting of international specialists in the field of von Willebrand disease (VWD) was held in the Åland islands in 1998 where Erik von Willebrand had first observed a bleeding disorder in some members of a family from Föglö and a summary of the meeting was published in 1999. The second meeting was held in 2010 and a report of the meeting was published in 2012. Topics covered included progress in understanding of VWD over the last 50 years; multimers; classification of VWD; pharmacokinetics and laboratory assays; genetics; treating the paediatric patient; prophylaxis; geriatrics; gene therapy and treatment guidelines. This third meeting held over 3 days covered the structure and function of von Willebrand factor (VWF); type 1 VWD, the most common form of the disease; a lifespan of pharmacokinetics in VWD; detecting inhibitors in VWD patients; and special challenges in understanding and treating the female VWD patient.


Asunto(s)
Enfermedades de von Willebrand/diagnóstico , Enfermedades de von Willebrand/terapia , Animales , Factor VIII/metabolismo , Femenino , Humanos , Enfermedades de von Willebrand/genética , Enfermedades de von Willebrand/metabolismo , Factor de von Willebrand/metabolismo
10.
Plant Biol (Stuttg) ; 25(4): 571-578, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36920172

RESUMEN

The residues of glyphosate are found to remain in soils longer than previously reported, affecting rhizosphere microbes. This may adversely affect crop and other non-target plants because the plant's resilience and resistance largely rely on plant-associated microbes. Ubiquitous glyphosate residues in soil and how they impact mutualistic microbes inhabiting the aboveground plant parts are largely unexplored. We studied the effects of herbicide residues in soil on Epichloë sp., which are common endophytic symbionts inhabiting aerial parts of cool-season grasses. In this symbiosis, the obligate symbiont subsists entirely on its host plant, and in exchange, it provides alkaloids conferring resistance to herbivores for the host grass that invests little in its own chemical defence. We first show decreased growth of Epichloë endophytes in vitro when directly exposed to two concentrations of glyphosate or glyphosate-based herbicides. Second, we provide evidence for a reduction of Epichloë-derived, insect-toxic loline alkaloids in endophyte-symbiotic meadow fescue (F. pratensis) plants growing in soil with a glyphosate history. Plants were grown for 2 years in an open field site, and natural herbivore infestation was correlated with the glyphosate-mediated reduction of loline alkaloid concentrations. Our findings indicate that herbicides residing in soil not only affect rhizosphere microbiota but also aerial plant endophyte functionality, which emphasizes the destructive effects of glyphosate on plant symbiotic microbes, here with cascading effects on plant-pest insect interactions.


Asunto(s)
Alcaloides , Epichloe , Herbicidas , Herbicidas/farmacología , Suelo , Poaceae , Simbiosis , Endófitos , Plantas , Epichloe/química
11.
Ann Oncol ; 22(2): 458-67, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20716627

RESUMEN

BACKGROUND: Synovial sarcoma (SS) is a malignant soft tissue sarcoma with a poor prognosis because of late local recurrence and distant metastases. To our knowledge, no studies have minimum follow-up of 10 years that evaluate long-term outcomes for survivors. PATIENTS AND METHODS: Data on 62 patients who had been treated for SS from 1968 to 1999 were studied retrospectively in a multicenter study. Mean follow-up of living patients was 17.2 years and of dead patients 7.7 years. RESULTS: Mean age at diagnosis was 35.4 years (range 6-82 years). Overall survival was 38.7%. The 5-year survival was 74.2%; 10-year survival was 61.2%; and 15-year survival was 46.5%. Fifteen patients (24%) died of disease after 10 years of follow-up. Local recurrence occurred after a mean of 3.6 years (range 0.5-14.9 years) and metastases at a mean of 5.7 years (range 0.5-16.3 years). Only four patients were treated technically correctly with a planned biopsy followed by a wide resection or amputation. Factors associated with significantly worse prognosis included larger tumor size, metastases at the time of diagnosis, high-grade histology, trunk-related disease, and lack of wide resection as primary surgical treatment. CONCLUSIONS: In SS, metastases develop late with high mortality. Patients with SS should be followed for >10 years.


Asunto(s)
Metástasis de la Neoplasia , Sarcoma Sinovial/patología , Sobrevivientes , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Adulto Joven
12.
Clin Orthop Relat Res ; 469(8): 2377-84, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21318628

RESUMEN

BACKGROUND: The risk of noncontact ACL injury reportedly is increased in patients with a greater posterior tibial slope (PTS), but clinical data are inconsistent. It is unclear whether the medial and lateral PTSs have a different impact on this connection. It also is unknown whether the meniscal slope (MS) is associated with ACL injury. PATIENTS/METHODS: Using MRI, we compared the medial and lateral PTSs and MSs separately in 55 matched pairs of patients with isolated noncontact ACL injuries and a control group. RESULTS: Neither the PTS nor the relative difference between the medial and lateral PTSs differed between groups. In contrast, the lateral MS was greater with ACL injuries: 2.0° versus -2.7° in males with and without ACL injury and 1.7° versus -0.9 in females. Uninjured females had a greater PTS than males: 4.9° versus 3.0° in females and males medially, respectively; 5.7° versus 4.0° lateral. CONCLUSIONS: There is no obvious link between the medial or lateral PTSs and ACL injury, and there is no obvious link between the relative difference in the medial and lateral PTSs and noncontact ACL injury. However, a greater lateral MS may indicate a greater risk of injury. The PTS can differ between the genders but the average difference is small. LEVEL OF EVIDENCE: Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Traumatismos de la Rodilla/fisiopatología , Meniscos Tibiales/fisiopatología , Tibia/fisiopatología , Femenino , Humanos , Modelos Logísticos , Imagen por Resonancia Magnética , Masculino , Pronóstico , Rango del Movimiento Articular/fisiología
13.
Pathol Biol (Paris) ; 59(1): 19-25, 2011 Feb.
Artículo en Francés | MEDLINE | ID: mdl-20889269

RESUMEN

OBJECTIVES: Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has recently been introduced in diagnostic microbiology laboratories for the identification of microorganisms. The mass fingerprint obtained by analyzing the ribosomal proteins and proteins associated with membranes is compared to spectra and superspectra of database. Microbiological Laboratory of Mulhouse acquired this system 1 year ago. METHOD: The MALDI-TOF MS analyses of all strains were performed on Axima(®) (Shimadzu), data analysis with Saramis(®) software (Anagnostec) and integration with SirWeb(®) software (I2A society). RESULTS: Rapidly, laboratory technicians and biologists are able to turn the system after a few days of training. The data prospectively gathered in the present study demonstrated that MALDI-TOF mass spectrometry identification is an efficient method included fastidious bacteria. Exactly 98.8 % of 10,000 isolates were identified in genus and species levels. Use of identification techniques was seldom necessary for a few clinical relevant isolates. The database is in constant evolution. The superspectra contain characteristic signals of genus, species allowing reliable microorganism identifications with high confidence. CONCLUSION: In conclusion, our results show that MALDI-TOF MS is a fast and reliable technique for identification of most bacterial strains routinely isolated in a clinical microbiology. Identification and susceptibility testing with a single cell colony are more often possible. The simple tests, such as Gram staining and oxidase and catalase tests are usually performed in our laboratory.


Asunto(s)
Infecciones Bacterianas/microbiología , Proteínas Bacterianas/análisis , Técnicas de Tipificación Bacteriana/métodos , Laboratorios de Hospital , Proteínas de la Membrana/análisis , Proteínas Ribosómicas/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Bacterias/química , Bacterias/aislamiento & purificación , Proteínas Fúngicas/análisis , Hongos/química , Hongos/aislamiento & purificación , Humanos , Técnicas In Vitro , Micosis/microbiología , Programas Informáticos , Especificidad de la Especie
14.
Transl Psychiatry ; 11(1): 544, 2021 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-34675189

RESUMEN

While a large body of literature documents the impairing effect of anxiety on cognition, performing a demanding task was shown to be effective in reducing anxiety. Here we explored the mechanisms of this anxiolytic effect by examining how a pharmacological challenge designed to improve attentional processes influences the interplay between the neural networks engaged during anxiety and cognition. Using a double-blind between-subject design, we pharmacologically manipulated working memory (WM) using a single oral dose of 20 mg methylphenidate (MPH, cognitive enhancer) or placebo. Fifty healthy adults (25/drug group) performed two runs of a WM N-back task in a 3 T magnetic resonance imaging scanner. This task comprised a low (1-Back) and high (3-Back) WM load, which were performed in two contexts, safety or threat of shocks (induced-anxiety). Analyses revealed that (1) WM accuracy was overall improved by MPH and (2) MPH (vs. placebo) strengthened the engagement of regions within the fronto-parietal control network (FPCN) and reduced the default mode network (DMN) deactivation. These MPH effects predominated in the most difficult context, i.e., threat condition, first run (novelty of the task), and 3-Back task. The facilitation of neural activation can be interpreted as an expansion of cognitive resources, which could foster both the representation and integration of anxiety-provoking stimuli as well as the top-down regulatory processes to protect against the detrimental effect of anxiety. This mechanism might establish an optimal balance between FPCN (cognitive processing) and DMN (emotion regulation) recruitment.


Asunto(s)
Metilfenidato , Adulto , Ansiedad/tratamiento farmacológico , Trastornos de Ansiedad , Cognición , Humanos , Memoria a Corto Plazo
15.
Hand Surg Rehabil ; 40(1): 32-39, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32987168

RESUMEN

Chronic exertional compartment syndrome (CECS) of the upper limbs is less well known than its equivalent in the lower limbs, thus its diagnosis is often delayed. Our goals were to evaluate the impact of CECS on activities of daily living and work-related activities and to report the functional outcomes after minimally invasive fasciotomy. This was a retrospective study of patients with CECS of the upper limb who were operated at two hospitals between 2008 and 2019. Thirty patients were reviewed an average of 5 years after minimally invasive fasciotomy: 26 had CECS of the forearm, 3 of the thenar compartment and 1 of the first interosseous compartment. For the evaluation, patients were asked to assess their pain on a visual analog scale (VAS), complete the QuickDASH questionnaire and rate their satisfaction with the outcome. Preoperative pain on the VAS was 7.45/10 with a negative impact on activities of daily living in 97% of patients, and on work-related activities in 77% of patients with 17% requiring a career change. The mean time to surgical treatment was 5 years. The mean QuickDASH at the final assessment was 6.0 (0-31.8) with a significant decrease in pain on VAS of 1.9/10 (p < 0.01). Seventy-seven percent of patients had very good results while 13% had good results. Full healing was achieved in 63% of patients and physical performance improved in 50%. Seventy-seven percent of patients were either satisfied or very satisfied with the outcome. One patient had a recurrence requiring surgical revision. CECS affects athletes of all levels and impacts both activities of daily living and work-related activities. We need to greatly expand our education and prevention efforts for CECS. Mini-open fasciotomy yields good results.


Asunto(s)
Síndrome Compartimental Crónico de Esfuerzo , Actividades Cotidianas , Descompresión Quirúrgica , Antebrazo , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
16.
Adv Exp Med Biol ; 661: 187-200, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20204731

RESUMEN

Hypoxic pulmonary vasoconstriction (HPV) is an essential mechanism of the lung matching blood perfusion to ventilation during local alveolar hypoxia. HPV thus optimizes pulmonary gas exchange. In contrast chronic and generalized hypoxia leads to pulmonary vascular remodeling with subsequent pulmonary hypertension and right heart hypertrophy. Among other non-selective cation channels, the family of classical transient receptor potential channels (TRPC) has been shown to be expressed in pulmonary arterial smooth muscle cells. Among this family, TRPC6 is essential for the regulation of acute HPV in mice. Against this background, in this chapter we give an overview about the TRPC family and their role in HPV.


Asunto(s)
Hipoxia/metabolismo , Pulmón , Isoformas de Proteínas/metabolismo , Arteria Pulmonar/fisiología , Canales de Potencial de Receptor Transitorio/metabolismo , Vasoconstricción/fisiología , Animales , Calcio/metabolismo , Humanos , Pulmón/irrigación sanguínea , Pulmón/metabolismo , Filogenia , Isoformas de Proteínas/química , Isoformas de Proteínas/clasificación , Isoformas de Proteínas/genética , Estructura Secundaria de Proteína , Transducción de Señal/fisiología , Canales de Potencial de Receptor Transitorio/química , Canales de Potencial de Receptor Transitorio/clasificación , Canales de Potencial de Receptor Transitorio/genética
17.
Curr Med Chem ; 16(16): 2021-41, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19519379

RESUMEN

Plasmalogens are a specific glycerophospholipid class containing a vinyl ether moiety at the sn-1-position of the glycerol backbone. The high susceptibility of this vinyl ether bond to oxidative damage and traces of acids may indicate the possible function of plasmalogens in biological systems: The regarded cell-internal antioxidative defense of membranes by protecting other phospholipids or lipoprotein particles against oxidative stress is controversial. Reactive oxygen species preferably affect the vinyl ether function as well as the olefinic acyl residues at the sn-2-position of plasmalogens. This review is dedicated to the role of plasmalogens in different cells and tissues as spermatozoal cells or brain tissue. The first chapter of this review will discuss the molecular structure and chemistry of plasmalogen molecules, their distributions in cells and tissues and the species-specificity. In the second chapter their functions as lipid mediators will be considered and the controversial antioxidative function will be discussed. The supposed function of plasmalogens as "scavengers" for reactive oxygen species (ROS) in biological membranes is challenged by the finding that plasmalogen oxidation products as alpha-hydroxyaldehydes and plasmalogen epoxides accumulate in all chronic diseases as atherosclerosis and myocardial infarction, upon aging as well as in Alzheimers disease and other neuropathological conditions. All these conditions, characterized by increased membrane instability and oxidative damage, will be reviewed in chapter three. Chronically proceeding processes can be described by permanently invading polymorphonuclear neutrophils into inflammatory loci. The degranulation of the azurophilic granula in polymorphonuclear leukocytes causes the release of highly reactive substances, for instance the myeloperoxidase-generated hypochlorous acid (HOCl) acting as effective oxidant. Therefore, special attention will be paid to neutrophil-derived HOCl. The last chapter deals with currently used methods of detecting plasmalogens and their degradation products. Although chromatographic methods will be also discussed, special attention will be given to (31)P NMR spectroscopy and soft ionization techniques of mass spectrometry as electrospray ionization or matrix-assisted laser desorption and ionization time-of-flight mass spectrometry.


Asunto(s)
Envejecimiento/metabolismo , Membrana Celular/metabolismo , Enfermedad , Plasmalógenos/análisis , Plasmalógenos/metabolismo , Animales , Humanos , Inflamación/metabolismo , Oxidación-Reducción , Plasmalógenos/química
18.
Theriogenology ; 71(4): 568-75, 2009 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-18950847

RESUMEN

The detailed comparative analysis of sperm lipids could essentially contribute to a better understanding of membrane function in the context of fertilization and, moreover, of sperm preservation. The application of sensitive analytical methods is particularly necessary for endangered species as the available amount of spermatozoa (and, accordingly, extractable lipids) is strongly limited. It will be shown that matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) is a fast, simple and sensitive method for the determination of the phospholipid composition of spermatozoa from several ruminantia (cattle, roe deer, Klipspringer) and feloideae species (domestic cat, Siberian tiger, fosa). Characteristic "fingerprints" are obtained from the positive ion spectra that allow the differentiation between both animal groups. In contrast to the lipid extracts of ruminantia spermatozoa which predominantly contain ether lipids including essential amounts of plasmalogens, the more complex phospholipid composition of feloideae spermatozoa is clearly dominated by diacyl phospholipids and contains only marginal amounts of plasmalogens. It will also be shown that the lipid compositions of ejaculated, electroejaculated and cauda epididymal spermatozoa of the same species are very similar and give comparable data. Therefore, the analysis of ejaculated spermatozoa is not an absolute must.


Asunto(s)
Felidae/fisiología , Fosfolípidos/química , Rumiantes/fisiología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/veterinaria , Espermatozoides/citología , Animales , Masculino , Fosfolípidos/metabolismo , Especificidad de la Especie , Espermatozoides/fisiología
19.
J Anim Physiol Anim Nutr (Berl) ; 93(4): 410-22, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18484967

RESUMEN

Alterations of the phospholipid (PL) compositions of body fluids are assumed to be indicative of inflammatory diseases, e.g. rheumatoid arthritis (RA). Recently, we have shown that particularly the phosphatidylcholine/lysophosphatidylcholine (PC/LPC) ratio determined in human synovial fluids (SF) and sera represents a reliable measure of the inflammatory state in RA patients. However, it is not yet clear to what extent the PC/LPC ratio is also affected by nutrition habits. In the present study, the PL and the corresponding acyl chain compositions of human body fluids (SF and serum of RA patients as well as serum from healthy volunteers) are compared with those of two other mammalian species (horses and dogs suffering from degenerative joint diseases as well as healthy controls) by high-resolution 31P-nuclear magnetic resonance (NMR) spectroscopy and matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS). The most important result of this study is that the PL compositions of SF and serum of horse and dog are comparable with those of human body fluids. Compared with humans, however, the horse body fluid contains less PCs with highly unsaturated arachidonoyl residues, while that of dogs possesses the highest content of arachidonoyl-containing PC. These species-related differences stem primarily from different nutrition habits (meat vs. plants).


Asunto(s)
Caballos/sangre , Espectroscopía de Resonancia Magnética/métodos , Fosfolípidos/sangre , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Líquido Sinovial/química , Adulto , Animales , Perros , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fosfolípidos/análisis , Especificidad de la Especie
20.
ISME J ; 13(5): 1119-1132, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30531893

RESUMEN

Identifying the roles played by individual heterotrophic bacteria in the degradation of high molecular weight (HMW) substrates is critical to understanding the constraints on carbon cycling in the ocean. At five sites in the Atlantic Ocean, we investigated the processing of organic matter by tracking changes in microbial community composition as HMW polysaccharides were enzymatically hydrolysed over time. During this investigation, we discovered that a considerable fraction of heterotrophic bacteria uses a newly-identified 'selfish' mode of substrate processing. We therefore additionally examined the balance of individual substrate utilisation mechanisms at different locations by linking individual microorganisms to distinct substrate utilisation mechanisms. Through FISH and uptake of fluorescently-labelled polysaccharides, 'selfish' organisms were identified as belonging to the Bacteroidetes, Planctomycetes and Gammaproteobacteria. 'Sharing' (extracellular enzyme producing) and 'scavenging' (non-enzyme producing) organisms predominantly belonged to the Alteromonadaceae and SAR11 clades, respectively. The extent to which individual mechanisms prevail depended on the initial population structure of the bacterial community at a given location and time, as well as the growth rate of specific bacteria. Furthermore, the same substrate was processed in different ways by different members of a pelagic microbial community, pointing to significant follow-on effects for carbon cycling.


Asunto(s)
Bacterias/metabolismo , Agua de Mar/microbiología , Alteromonadaceae/enzimología , Alteromonadaceae/metabolismo , Océano Atlántico , Bacterias/aislamiento & purificación , Bacteroidetes/metabolismo , Ciclo del Carbono , Gammaproteobacteria/metabolismo , Procesos Heterotróficos , Polisacáridos/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA