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1.
J Phys Condens Matter ; 36(23)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38417174

RESUMEN

Two-dimensional transition metal dichalcogenides (TMDs) and alloys based on them, is a promising platform for creating opto- and nanoelectronic devices. For layered alloys, there is a strong need to theoretically determine the frequencies of vibrational modes and dependences of their energies on the stoichiometric composition. By comparing experimentally measured Raman modes with theoretical predictions, it becomes possible to determine the stoichiometric composition of the manufactured alloys. In this work, we investigated the vibrational properties of monolayer MoS2xSe2(1-x)alloys utilizing density functional theory method and confirmed them experimentally by Raman spectroscopy. The dependence of A1' and E12g'dactylographic' modes on the stoichiometric composition of alloys has been calculated. When in pure MoSe2structure Se atoms are substituted by S atoms, the in-plane E12g(S-Mo), E12g(Se-Mo) and out-plane A1' (S-Mo) modes shifted linearly inxto higher frequencies, while the out-plane A1' (Se-Mo) mode did the same in nonlinear way. We also identified the E12g(Se-Mo-S) mode, which specific for the MoS2xSe2(1-x)alloys and does not appear in pure two-component TMDs.

2.
Surg Endosc ; 34(7): 3002-3010, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31485928

RESUMEN

SETTING: The physiological and anatomical changes that occur as a consequence of bariatric surgery result in macro- and micro-nutritional deficiencies, especially iron deficiency. The reported incidence of iron deficiency and associated anemia after bariatric surgery varies widely across studies. OBJECTIVES: The aim of this systematic review is to quantify the impact of Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) on the incidence of iron deficiency. METHODS: Databases including Ovid Medline, Ovid Embase, Helthstar, Scopus, Cochrane (CDSR), LILACS, and ClinicalKey were searched for original articles with additional snowballing search. Search terms included Obesity, nutrient deficiency, iron deficiency, iron deficiency anemia, bariatric surgery, Roux-en-Y gastric bypass, and sleeve gastrectomy. Original articles reporting the incidence of iron deficiency and anemia pre- and post-RYGB and SG from January 2000 to January 2015 with minimum 1-year follow-up were selected. Data extraction from selected studies was based on protocol-defined criteria. RESULTS: There were 1133 articles screened and 20 studies were included in the final analysis. The overall incidence of iron deficiency was 15.2% pre-operatively and 16.6% post-operatively. When analyzed by procedure, the incidence of iron deficiency was 12.9% pre-RYGB versus 24.5% post-RYGB and 36.6% pre-SG versus 12.4% post-SG. The incidence of iron deficiency-related anemia was 16.7% post-RYGB and 1.6% post-SG. Risk factors for iron deficiency were premenopausal females, duration of follow-up, and pre-operative iron deficiency. Prophylactic iron supplementation was reported in 16 studies and 2 studies provided therapeutic iron supplementation only for iron-deficient patients. Iron dosage varied from 7 to 80 mg daily across studies. CONCLUSION: Iron deficiency is frequent in people with obesity and may be exacerbated by bariatric surgery, especially RYGB. Further investigation is warranted to determine appropriate iron supplementation dosages following bariatric surgery. Careful nutritional surveillance is important, especially for premenopausal females and those with pre-existing iron deficiency.


Asunto(s)
Anemia Ferropénica/epidemiología , Anemia Ferropénica/etiología , Gastrectomía/efectos adversos , Derivación Gástrica/efectos adversos , Complicaciones Posoperatorias/etiología , Adulto , Cirugía Bariátrica/métodos , Femenino , Gastrectomía/métodos , Derivación Gástrica/métodos , Humanos , Incidencia , Hierro/uso terapéutico , Masculino , Persona de Mediana Edad , Obesidad/cirugía , Obesidad Mórbida/cirugía , Complicaciones Posoperatorias/epidemiología , Premenopausia , Factores de Riesgo
3.
Sci Rep ; 9(1): 4563, 2019 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-30872589

RESUMEN

Signaling via Toll-like receptor 4 (TLR4) in macrophages constitutes an essential part of the innate immune response to bacterial infections. Detailed and quantified descriptions of TLR4 signal transduction would help to understand and exploit the first-line response of innate immune defense. To date, most mathematical modelling studies were performed on transformed cell lines. However, properties of primary macrophages differ significantly. We therefore studied TLR4-dependent activation of NF-κB transcription factor in bone marrow-derived and peritoneal primary macrophages. We demonstrate that the kinetics of NF-κB phosphorylation and nuclear translocation induced by a wide range of bacterial lipopolysaccharide (LPS) concentrations in primary macrophages is much faster than previously reported for macrophage cell lines. We used a comprehensive combination of experiments and mathematical modeling to understand the mechanisms of this rapid response. We found that elevated basal NF-κB in the nuclei of primary macrophages is a mechanism increasing native macrophage sensitivity and response speed to the infection. Such pre-activated state of macrophages accelerates the NF-κB translocation kinetics in response to low agonist concentrations. These findings enabled us to refine and construct a new model combining both NF-κB phosphorylation and translocation processes and predict the existence of a negative feedback loop inactivating phosphorylated NF-κB.


Asunto(s)
Núcleo Celular/metabolismo , Lipopolisacáridos/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , FN-kappa B/metabolismo , Línea Celular , Citosol/metabolismo , Activación de Macrófagos/inmunología , Modelos Biológicos , Fosforilación , Transporte de Proteínas , Transducción de Señal , Receptor Toll-Like 4/agonistas , Receptor Toll-Like 4/metabolismo , Ubiquitinación
4.
Wiad Lek ; 71(6): 1219-1223, 2018.
Artículo en Ruso | MEDLINE | ID: mdl-30267503

RESUMEN

OBJECTIVE: Introduction: Somatic illness, objectively and subjectively, can become a difficult life situation for a person. The adolescent's experience of illness is determined by the specifics of a particular age period. To develop an effective rehabilitation program, it is necessary to study the personal characteristics of the adolescent and his social environment, which may be resourceful. The aim: To conduct a theoretical analysis of publications about psychological resources coping with somatic illness in adolescents. PATIENTS AND METHODS: Materials and methods: The analysis of scientific publications on this topic. RESULTS: Review and conclusions: In the process of overcoming the illness, the adolescent accumulates his internal and external resources. External resources are mostly described as support from the family. Personal resources are described by a wide range of personal qualities. It is necessary to develop a system of psychological resources for coping with somatic illness in adolescents.


Asunto(s)
Adaptación Psicológica , Síntomas sin Explicación Médica , Medio Social , Adolescente , Humanos
5.
BMC Immunol ; 19(1): 26, 2018 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-30055563

RESUMEN

BACKGROUND: Agonists of TLR3 and TLR4 are effective immunoadjuvants for different types of vaccines. The mechanisms of their immunostimulatory action differ significantly; these differences are particularly critical for immunization with non-replicating adenovirus vectors (rAds) based vaccines. Unlike traditional vaccines, rAd based vaccines are not designed to capture vaccine antigens from the external environment by antigen presenting cells (APCs), but rather they are targeted to the de novo synthesis of vaccine antigens in APCs transfected with rAd. To date, there is no clear understanding about approaches to improve the efficacy of rAd vaccinations with immunoadjuvants. In this study, we investigated the immunoadjuvant effect of TLR3 and TLR4 agonists on the level of activation of APCs during vaccination with rAds. RESULTS: We demonstrated that TLR3 and TLR4 agonists confer different effects on the molecular processes in APCs that determine the efficacy of antigen delivery and activation of antigen-specific CD4+ and CD8+ T cells. APCs activated with agonists of TLR4 were characterized by up-regulated production of target antigen mRNA and protein encoded in rAd, as well as enhanced expression of the co-activation receptors CD80, CD86 and CD40, and pro-inflammatory cytokines TNF-α, IL6 and IL12. These effects of TLR4 agonists have provided a significant increase in the number of antigen-specific CD4+ and CD8+ T cells. TLR3 agonist, on the contrary, inhibited transcription and synthesis of rAd-encoded antigens, but improved expression of CD40 and IFN-ß in APCs. The cumulative effect of TLR3 agonist have resulted in only a slight improvement in the activation of antigen-specific T cells. Also, we demonstrated that IFN-ß and TNF-α, secreted by APCs in response to TLR3 and TLR4 agonists, respectively, have an opposite effect on the transcription of the targeted gene encoded in rAd. Specifically, IFN-ß inhibited, and TNF-α stimulated the expression of target vaccine antigens in APCs. CONCLUSIONS: Our data demonstrate that agonists of TLR4 but not TLR3 merit further study as adjuvants for development of vaccines based on recombinant adenoviral vectors.


Asunto(s)
Vacunas contra el Adenovirus/inmunología , Adyuvantes Inmunológicos/farmacología , Presentación de Antígeno , Células Dendríticas/efectos de los fármacos , Receptor Toll-Like 3/agonistas , Receptor Toll-Like 4/agonistas , Animales , Antígeno B7-1/inmunología , Antígeno B7-2/inmunología , Linfocitos T CD4-Positivos/inmunología , Antígenos CD40/inmunología , Linfocitos T CD8-positivos/inmunología , Células Dendríticas/inmunología , Vectores Genéticos/inmunología , Inmunización , Interferón beta/inmunología , Interleucina-12/inmunología , Interleucina-6/inmunología , Ratones , Ratones Endogámicos BALB C , Células TH1/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Vacunas Sintéticas/inmunología
6.
Surg Endosc ; 32(7): 3009-3023, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29721749

RESUMEN

BACKGROUND: A needs assessment identified a gap in teaching and assessment of laparoscopic suturing (LS) skills. The purpose of this review is to identify assessment tools that were used to assess LS skills, to evaluate validity evidence available, and to provide guidance for selecting the right assessment tool for specific assessment conditions. METHODS: Bibliographic databases were searched till April 2017. Full-text articles were included if they reported on assessment tools used in the operating room/simulation to (1) assess procedures that require LS or (2) specifically assess LS skills. RESULTS: Forty-two tools were identified, of which 26 were used for assessing LS skills specifically and 26 for procedures that require LS. Tools had the most evidence in internal structure and relationship to other variables, and least in consequences. CONCLUSION: Through identification and evaluation of assessment tools, the results of this review could be used as a guideline when implementing assessment tools into training programs.


Asunto(s)
Competencia Clínica/normas , Educación de Postgrado en Medicina/métodos , Gastroenterología/educación , Laparoscopía/educación , Técnicas de Sutura/educación , Suturas , Humanos
7.
Eur J Pharmacol ; 811: 249-259, 2017 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-28668507

RESUMEN

Synthetic 14 AA peptide (Gepon) derived from the hinge region of ezrin, a protein that links cell surface molecules to intracellular actin filaments, accelerates and facilitates wound and ulcer healing in clinical applications. However, the molecular mechanisms underlying this phenomenon and involved in enhanced healing of wounds with Gepon are not yet understood. The purpose of current study was to investigate intracellular signaling pathways involved in the effect of this peptide on wild type and genetically modified (CD44 KO) NIH/3T3 embryonic mouse fibroblasts. Gepon treatment of NIH/3T3 cells resulted in morphological and biochemical changes, characteristic of differentiated fibroblasts. While treatment of NIH/3T3 cells with TGF-ß1 triggered the activation of both canonical and non-canonical signaling pathways, exposure of fibroblasts to Gepon activated only the ERK1/2 dependent pathway without modulating SMAD dependent signaling pathway. Knocking out hyaluronic acid CD44 receptor did not change Gepon or TGF-ß1 dependent activation of intracellular signaling pathways and assembling of α-SMA-positive filaments. Gepon dependent differentiation of NIH/3T3 fibroblasts is based on activation of ERK1/2 kinase, non-canonical intracellular signaling pathway. Our data suggest that the treatment of fibroblasts with Gepon triggers activation of the non-canonical (SMAD independent) intracellular signaling pathway that involves ERK1/2kinase phosphorylation. Activation of the MAPK signaling pathway and the increase in formation of α-SMA containing stress filaments induced by Gepon were independent on presence of CD44 receptor in NIH/3T3 fibroblasts. Thus, our observation designates the significance and sufficiency of MAPK pathway mediated activation of fibroblasts with Gepon for healing of erosion, ulcers and wounds.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Proteínas del Citoesqueleto/química , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fragmentos de Péptidos/química , Fragmentos de Péptidos/farmacología , Secuencia de Aminoácidos , Animales , Movimiento Celular/efectos de los fármacos , Colágeno Tipo I/genética , Fibroblastos/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Técnicas de Inactivación de Genes , Receptores de Hialuranos/deficiencia , Receptores de Hialuranos/genética , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Ratones , Células 3T3 NIH , Proteínas Proto-Oncogénicas c-fos/metabolismo , Transducción de Señal/efectos de los fármacos , Factor de Crecimiento Transformador alfa/metabolismo
8.
Genome Announc ; 5(10)2017 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-28280035

RESUMEN

Serratia marcescens is a frequent cause of health care-associated infections and has led to multiple outbreaks. Here, we report the draft genome of a multidrug-resistant S. marcescens strain 189 which was isolated in 2012 as a predominant clone in a neonatal hospital in Kemerovo.

9.
Surg Endosc ; 30(3): 832-44, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26092014

RESUMEN

BACKGROUND: Multiple tools are available to assess clinical performance of laparoscopic cholecystectomy (LC), but there are no guidelines on how best to implement and interpret them in educational settings. The purpose of this systematic review was to identify and critically appraise LC assessment tools and their measurement properties, in order to make recommendations for their implementation in surgical training. METHODS: A systematic search (1989-2013) was conducted in MEDLINE, Embase, Scopus, Cochrane, and grey literature sources. Evidence for validity (content, response process, internal structure, relations to other variables, and consequences) and the conditions in which the evidence was obtained were evaluated. RESULTS: A total of 54 articles were included for qualitative synthesis. Fifteen technical skills and two non-technical skills assessment tools were identified. The 17 tools were used for either: recorded procedures (nine tools, 60%), direct observation (five tools, 30%), or both (three tools, 18%). Fourteen (82%) tools reported inter-rater reliability and one reported a Generalizability Theory coefficient. Nine (53%) had evidence for validity based on clinical experience and 11 (65%) compared scores to other assessments. Consequences of scores, educational impact, applications to residency training, and how raters were trained were not clearly reported. No studies mentioned cost. CONCLUSIONS: The most commonly reported validity evidence was inter-rater reliability and relationships to other known variables. Consequences of assessments and rater training were not clearly reported. These data and the evidence for validity should be taken into consideration when deciding how to select and implement a tool to assess performance of LC, and especially how to interpret the results.


Asunto(s)
Colecistectomía Laparoscópica/normas , Competencia Clínica , Garantía de la Calidad de Atención de Salud , Humanos , Reproducibilidad de los Resultados
10.
J Surg Educ ; 72(3): 542-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25496795

RESUMEN

OBJECTIVES: Despite evidence supporting the value of the Fundamentals of Laparoscopic Surgery (FLS) curriculum, surgical educators still find it challenging to motivate residents to practice. Wiggio is an online networking and collaboration tool that allows learners to track performance, see what their peers are doing, and send and receive updates. The purpose of this study was to assess whether using Wiggio increases practice and improves performance of the FLS manual skills. DESIGN: After baseline FLS testing, residents were randomized into control (C) and Wiggio (W) groups. The practice events, time spent practicing, and best scores were recorded. Residents in the W group interacted with each other via the Wiggio website. The website moderator sent motivational messages, calendar reminders, and FLS-related articles. The best times and progress graphs for each resident were also posted online. After 4 weeks, all residents underwent final FLS testing and filled out a questionnaire. SETTING: The study was performed in a tertiary care center, at the Steinberg-Bernstein Centre for Minimally Invasive Surgery at the Montreal General Hospital. PARTICIPANTS: Postgraduate year-1 and postgraduate year-2 general surgery residents with no or minimal FLS simulator experience were included. RESULTS: Of the 15 eligible residents, 14 participated, with 7 residents in each group. The FLS scores were similar at baseline (C = 56.9 [±14.2], W = 57. 6 [±14.7]; p = 0.93). During the study period, twice as many residents in the W group practiced compared with those in the C group (4 vs 2); W-group residents reported more practice events than the C-group residents did (14 vs 4) and spent more time practicing in the laboratory (1035 vs 480 minutes). These results did not reach statistical significance. During practice sessions, proficiency scores were achieved for 40% of the tasks in the W group compared with 8.6% in the C group; however, this difference was also not significant. There was no difference in the FLS scores in both groups at the end of the study. The moderator spent an average of 6.5 minutes per day sending messages and managing the Wiggio website. CONCLUSIONS: Participation in Wiggio seems to increase practice events and time spent training on FLS. Social networking may play a role in surgical education and learner motivation; however, the optimal use of Web 2.0 tools in resident education is not yet fully understood.


Asunto(s)
Educación de Postgrado en Medicina , Laparoscopía/educación , Motivación , Red Social , Adulto , Competencia Clínica , Curriculum , Femenino , Humanos , Internado y Residencia , Masculino , Encuestas y Cuestionarios , Grabación en Video
11.
Pharmacol Biochem Behav ; 82(3): 506-14, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16325897

RESUMEN

Thyroid hormones (TH) were hypothesized to affect behavior via neurotransmission alterations. The present study was aimed to reveal effects of chronic TH deficit and excess on some types of adaptive behavior (catalepsy, acoustic startle reflex, open-field performance), sexual arousal and cerebral 5-HT2A serotonin receptors of adult Wistar rats. Administration of thyroxine synthesis inhibitor, propylthiouracil (PTU, 50 mg/l, 28 days), in drinking water produced substantial decrease in plasma thyroxine level and body weight gain, attenuated significantly acoustic startle reflex amplitude, sexual motivation and plasma testosterone surge in response to receptive female introduction, increased predisposition to catalepsy without considerable effects on open-field performance. L-thyroxine treatment (T4, 0.5 mg/l, 28 days) caused significant plasma thyroxine augmentation, somatic growth retardation and disturbances in sexual but not in other types of behavior studied. TH dysfunctions markedly increased number of DOI-induced wet dog shakes reflecting high functional activity of 5-HT2A receptors without any effect on cortical 5-HT2A receptor mRNA level. The involvement of cerebral 5-HT2A receptors alterations at posttranslational level in mechanisms of TH effects on sexual arousal was suggested. The data attract particular attention to undesirable effects of PTU and L-thyroxine treatment on behavior.


Asunto(s)
Corteza Cerebral/metabolismo , Receptor de Serotonina 5-HT2A/metabolismo , Conducta Sexual Animal , Enfermedades de la Tiroides/fisiopatología , Animales , Secuencia de Bases , Catalepsia , Cartilla de ADN , Femenino , Masculino , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Receptor de Serotonina 5-HT2A/genética , Reflejo de Sobresalto , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Enfermedades de la Tiroides/metabolismo , Tiroxina/sangre
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