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1.
Ergonomics ; 65(11): 1578-1591, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35232328

RESUMEN

This article aims to analyse the integration of sex and gender (s/g) by ergonomics students during their internship at the master's degree level, following training sessions on s/g issues in the workplace. This exploratory research used a descriptive mixed-methods design, encompassing evaluation of students' intention to use the content from the training (n = 13 students), and a multiple case study (n = 5 ergonomics interventions). The results show that while students found the training relevant, they only minimally integrated s/g in their interventions and when they did, it was primarily from an anthropometric and physiological perspective. In addition to discussing the training format limitations, the article discusses barriers to this integration: combining learning about s/g issues with learning about activity analysis is challenging; employers' and workers' organisations may be reluctant to approach s/g issues; and it is difficult for an ergonomist to integrate these issues when the employer's request does not specify it.Practitioner summary: This article aims to analyse the integration of s/g by ergonomics students during their internships. Findings show that they only minimally considered s/g. The discussion examines s/g training, organisational obstacles to inclusion of s/g during interventions, and how ergonomists can consider s/g in their practice.


Asunto(s)
Ergonomía , Lugar de Trabajo , Masculino , Femenino , Humanos , Capacitación en Servicio , Estudiantes
2.
Clin Exp Optom ; 103(4): 501-506, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31773810

RESUMEN

BACKGROUND: Among technologies targeting mobile eye care, EyeNetra is a smartphone-based subjective refraction system. This study compared the results from this system with those of professional subjective refraction. Participant visual comfort and preference of results were also measured. METHODS: Thirty-six optometry-naïve participants (n = 36 eyes, aged 18-35 years), were randomly subjected to three refraction methods: professional subjective refraction, unassisted Netra (participants alone) and refined Netra (sphere results refined by a practitioner). Using a randomised, double-blind design, refraction results were mounted in a trial frame and distance logMAR visual acuities were measured. Subjective appreciation and visual comfort were assessed by questionnaire. Overall preference was ranked. RESULTS: Unassisted Netra yielded a median myopic overcorrection of 0.60 D (interquartile range [IQR] 0.25 to 0.94) compared to professional subjective refraction. Median equivalent sphere with unassisted Netra (-1.40 D, IQR -3.10 to -0.90) was significantly more myopic than refined Netra (-0.70 D, IQR -1.60 to -0.30) and then subjective refraction (-0.80 D, IQR -1.60 to -0.30) (all p-values < 0.01). Median visual acuity with professional subjective refraction (-0.16, IQR -0.22 to -0.09) was superior than unassisted Netra (-0.08, IQR -0.20 to 0.03) (p < 0.01). Subjective refraction was ranked first in preference of trial framed results by 72 per cent of participants; median preference rank favoured professional subjective refraction to both Netra results (all p < 0.01). For all questionnaire items, visual comfort was higher with subjective refraction than with unassisted Netra (all p < 0.04). CONCLUSION: The Netra device - especially when used without professional assistance and compared to subjective refraction - induces significant myopic overcorrection and lower levels of visual acuity, subjective preference and visual comfort.


Asunto(s)
Refracción Ocular/fisiología , Errores de Refracción/diagnóstico , Teléfono Inteligente , Pruebas de Visión/instrumentación , Agudeza Visual , Adolescente , Adulto , Método Doble Ciego , Diseño de Equipo , Femenino , Humanos , Masculino , Errores de Refracción/fisiopatología , Encuestas y Cuestionarios , Adulto Joven
3.
Ergonomics ; 62(10): 1313-1326, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31282825

RESUMEN

The efficiency of training programmes in handling designed to prevent injuries has rarely been demonstrated by studies in the workplace. This study aimed to identify factors that may favour or inhibit the application of safe handling principles by paramedics performing full-body transfers of patients from a stair chair to a stretcher. In an observational field study, handling methods used in 45 patient transfers from a stair chair to stretcher were characterised. Principles concerning the physical environment seem to be applied frequently, but those applicable during the transfer are neglected. Principles taught during training may not be applied due to the physical constraints of the workplace and the underestimation of risk exposure. The results suggest that training should be enhanced, not by focussing on handling techniques but by focussing on compromise and the capacity to adapt work techniques based on the working context and the team-mate.


Asunto(s)
Técnicos Medios en Salud/educación , Educación/métodos , Movimiento y Levantamiento de Pacientes/normas , Enfermedades Musculoesqueléticas/prevención & control , Traumatismos Ocupacionales/prevención & control , Adulto , Humanos , Persona de Mediana Edad , Camillas , Adulto Joven
4.
Appl Ergon ; 74: 177-185, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30487098

RESUMEN

Few studies have quantified the risk of musculoskeletal disorders during patient transfers in total assistance mode in real-life prehospital emergency care situations. An index to assess the overall risk of patient transfers was created; it makes it possible to quantify risk based on the patient's position and the height of the patient's location. An analysis of 71 transfers executed by paramedics in actual work situations showed that moving a patient from the ground was characterized by acute sagittal flexions and axial rotations, respectively, 42% and 12% of the time. When the patient was lying on a raised surface, the lifting index and perceived exertion were the lowest (2.55; easy). According to the overall risk index, patient transfers from the ground are the riskiest. Paramedics execute many risky lifts even in favorable patient handling contexts.


Asunto(s)
Técnicos Medios en Salud/estadística & datos numéricos , Movimiento y Levantamiento de Pacientes/efectos adversos , Enfermedades Musculoesqueléticas/etiología , Enfermedades Profesionales/etiología , Medición de Riesgo/estadística & datos numéricos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Movimiento/fisiología , Movimiento y Levantamiento de Pacientes/métodos , Posicionamiento del Paciente/efectos adversos , Posicionamiento del Paciente/métodos , Transferencia de Pacientes/métodos , Transferencia de Pacientes/estadística & datos numéricos , Postura , Adulto Joven
5.
J Inorg Biochem ; 189: 180-184, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30296621

RESUMEN

The effect of pressure on the Raman and fluorescence spectra of hematin anhydride (ß-hematin) is reported. In a diamond-anvil cell, DAC, with applied pressures up to 41 kbar, the Raman spectrum undergoes a series of intensity enhancements and increases in energy for many of the Raman-active bands up to a pressure of ~27 kbar. At higher pressures, there is either a leveling out or a decrease in the energies of these vibrational modes. The fluorescence bands also undergo a series of pressure- sensitive changes where, up to 10 kbar, there is a marked quenching of the intensity of the emissive bands, which is accompanied by a net increase in energy of the vibrational bands. The results are interpreted in terms of a high-pressure phase change, to account for the Raman shifts, and a separate defect or surface site of the emissive state, which is more efficiently quenched at higher pressure.


Asunto(s)
Anhídridos/química , Hemina/química , Presión , Espectrometría Raman
6.
Curr Gerontol Geriatr Res ; 2014: 949180, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24523731

RESUMEN

Introduction. In long-term care (LTC), person-centred approaches are encouraged. One such approach, relationship-based care (RBC), aims among other things to reduce residents' agitated behaviours. RBC has been used in numerous Quebec LTC facilities over the past decade but it has never been studied. Objective. Explore correlations between use of RBC by trained caregivers and the frequency of agitated and positive behaviours of residents with cognitive impairments. Methods. Two independent raters observed fourteen caregiver/resident dyads in two LTC facilities during assistance with hygiene and dressing. Checklists were used to quantify caregivers' RBC use and residents' agitated and positive behaviours. Results. Scores for RBC use were high, suggesting good application of the approach by caregivers. Correlation analyses showed that offering residents realistic choices and talking to them during care were associated with both positive and agitated behaviours (P from 0.03 to 0.003). However, many other components of RBC were not associated with residents' behaviours during care. Conclusions. There were only a few quantitative links between the RBC checklist items and the frequency of agitated or positive behaviours. Other studies with a more rigorous research design are needed to better understand the impact of relationship-based care on residents' behaviours.

7.
J Infect Dis ; 209(1): 140-9, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23922378

RESUMEN

Low reticulocytosis, indicating reduced red blood cell (RBC) output, is an important feature of severe malarial anemia. Evidence supports a role for Plasmodium products, especially hemozoin (Hz), in suppressed erythropoiesis during malaria, but the mechanism(s) involved remains unclear. Here, we demonstrated that low reticulocytosis and suppressed erythropoietin (Epo)-induced erythropoiesis are features of malarial anemia in Plasmodium yoelii- and Plasmodium berghei ANKA-infected mice, similar to our previous observations in Plasmodium chabaudi AS-infected mice. The magnitude of decreases in RBC was a reflection of parasitemia level, but low reticulocytosis was evident despite differences in parasitemia, clinical manifestation, and infection outcome. Schizont extracts and Hz from P. falciparum and P. yoelii and synthetic Hz suppressed Epo-induced proliferation of erythroid precursors in vitro but did not inhibit RBC maturation. To determine whether Hz contributes to malarial anemia, P. yoelii-derived or synthetic Hz was administered to naive mice, and the development of anemia, reticulocytosis, and RBC turnover was determined. Parasite-derived Hz induced significant decreases in RBC and increased RBC turnover with compensatory reticulocytosis, but anemia was not as severe as that in infected mice. Our findings suggest that parasite factors, including Hz, contribute to severe malarial anemia by suppressing Epo-induced proliferation of erythroid precursors.


Asunto(s)
Anemia/parasitología , Eritropoyesis/fisiología , Hemoproteínas/farmacología , Malaria/sangre , Reticulocitosis/fisiología , Análisis de Varianza , Anemia/sangre , Anemia/metabolismo , Animales , Recuento de Eritrocitos , Eritropoyesis/efectos de los fármacos , Femenino , Macrófagos/química , Macrófagos/parasitología , Malaria/parasitología , Ratones , Ratones Endogámicos C57BL , Monocitos/química , Monocitos/parasitología , Plasmodium , Reticulocitosis/efectos de los fármacos , Esquizontes/fisiología
8.
Anal Bioanal Chem ; 405(16): 5431-40, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23649925

RESUMEN

The pigment hemozoin is a natural by-product of the metabolism of hemoglobin by the parasites which cause malaria. Previously, hemozoin was demonstrated to have a very high nonlinear optical response enabling third harmonic generation (THG) imaging. In this study, we present a complete characterization of the nonlinear THG response of natural hemozoin in malaria-infected red blood cells, as well as in pure isostructural synthesized hematin anhydride, in order to determine optimal imaging parameters for detection. Our study demonstrates the wavelength range for optimal pulsed femtosecond laser excitation of THG from hemozoin crystals. In addition, we show the hemozoin crystal detection as a function of crystal size, incident laser power, and the emission response of the hemozoin crystals to different incident laser polarization states. Our systematic measurements of the nonlinear optical response from hemozoin establish detection limits, which are essential for the optimal design of malaria detection technologies that exploit the THG response of hemozoin.


Asunto(s)
Eritrocitos/parasitología , Hemoproteínas/análisis , Malaria/parasitología , Imagen Molecular/métodos , Cristalización , Hemina/química , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Microscopía Confocal/métodos , Plasmodium falciparum/patogenicidad
9.
Can J Aging ; 32(1): 57-72, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23339880

RESUMEN

The person-centered approach is increasingly recommended in long-term care facilities to increase quality of care. In Quebec, Canada,. caregivers were specifically trained in "relationship-based care. "This study analyzed caregivers' assessment of this approach's usefulness and their capacity, after training, to apply it to care practices. Questionnaires with open-ended questions were administered to caregivers (n= 392) one month after training. Caregivers' answers were categorized using a qualitative approach. Respondents perceive some features of this approach are beyond their reach or in opposition to their beliefs. They reported feeling pressure related to time constraints, their peers and the families of residents. These results indicate that training itself is insufficient to transform practice. Institutions wishing to implement such an approach must also act upon the beliefs of individuals, as well as upon work situations.


Asunto(s)
Envejecimiento , Demencia/enfermería , Personal de Salud/educación , Servicios de Salud para Ancianos , Cuidados a Largo Plazo , Atención Dirigida al Paciente , Adulto , Anciano , Geriatría/educación , Servicios de Salud para Ancianos/normas , Humanos , Atención Dirigida al Paciente/normas , Calidad de la Atención de Salud/normas , Quebec , Encuestas y Cuestionarios , Recursos Humanos
10.
PLoS One ; 6(10): e26495, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22028888

RESUMEN

Malaria is one of the most prevalent infectious diseases worldwide with more than 250 million cases and one million deaths each year. One of the well-characterized malarial-related molecules is hemozoin (HZ), which is a dark-brown crystal formed by the parasite and released into the host during the burst of infected red blood cells. HZ has a stimulatory effect on the host immune system such as its ability to induce pro-inflammatory mediators responsible for some of the malaria related clinical symptoms such as fever. However, the host serum proteins interacting with malarial HZ as well as how this interaction modifies its recognition by phagocytes remained elusive. In the actual study, using proteomic liquid chromatographic mass spectrometry (LC-MS/MS) and immunochemical approaches, we compared the serum protein profiles of malaria patients and healthy individuals. Particularly, we utilized the malarial HZ itself to capture serum proteins capable to bind to HZ, enabling us to identify several proteins such as apolipoprotein E (ApoE), serum amyloid A (SAA), gelsolin, complement factor H and fibrinogen that were found to differ among healthy and malaria individual. Of particular interest is LPS binding protein (LBP), which is reported herein for the first time in the context of malaria. LBP is usually produced during innate inflammatory response to gram-negative bacterial infections. The exact role of these biomarkers and acute phase responses in malaria in general and HZ in particular remains to be investigated. The identification of these inflammation-related biomarkers in malaria paves the way to potentially utilize them as diagnostic and therapeutic targets.


Asunto(s)
Malaria/metabolismo , Proteómica , Biomarcadores/sangre , Biomarcadores/metabolismo , Proteínas Sanguíneas/aislamiento & purificación , Proteínas Sanguíneas/metabolismo , Hemoproteínas/metabolismo , Humanos , Inflamación/metabolismo
11.
J Phys Chem B ; 115(15): 4419-26, 2011 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-21434658

RESUMEN

The local atomic structure around the central iron of the synthetic soluble analog of malarial pigment in acetic acid solution and with addition of chloroquine as found by X-ray absorption spectroscopy is reported. The special interest was drawn to the axial linkage between the central iron atom of the ferriprotoporphyrin IX (FePPIX) coordinated axially to the propionate group of the adjacent FePPIX. This kind of bonding is typical for hematin anhydride. Detailed analysis revealed differences in oxygen coordination sphere (part of dimer linkage bond) between synthetic equivalent of hemozoin in the powder state and dissolved in acetic acid and water at different concentrations mimicking the physiological condition of the parasite's food vacuole. The results of performed studies suggest that the molecular structure of synthetic analogue of hemozoin is no longer dimer-like in acidic solution. Further changes in atomic order around Fe are seen after addition of the antimalarial drug chloroquine.


Asunto(s)
Antimaláricos/química , Cloroquina/química , Hemoproteínas/química , Ácido Acético/química , Humanos , Malaria/tratamiento farmacológico , Modelos Moleculares , Espectroscopía de Absorción de Rayos X
12.
ASN Neuro ; 2(3): e00039, 2010 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-20689858

RESUMEN

The heparan sulfate proteoglycan glypican-1, the chondroitin sulfate proteoglycan phosphacan/RPTP (receptor protein-tyrosine phosphatase)-zeta/beta and the extracellular matrix protein tenascin-C were all found to be expressed by neural stem cells and by neural cells derived from them. Expression of proteoglycans and tenascin-C increased after retinoic acid induction of SSEA1-positive ES (embryonic stem) cells to nestin-positive neural stem cells, and after neural differentiation, proteoglycans and tenascin-C are expressed by both neurons and astrocytes, where they surround cell bodies and processes and in certain cases show distinctive expression patterns. With the exception of tenascin-C (whose expression may decrease somewhat), expression levels do not change noticeably during the following 2 weeks in culture. The significant expression, by neural stem cells and neurons and astrocytes derived from them, of two major heparan sulfate and chondroitin sulfate proteoglycans of nervous tissue and of tenascin-C, a high-affinity ligand of phosphacan/RPTP-zeta/beta, indicates that an understanding of their specific functional roles in stem cell neurobiology will be important for the therapeutic application of this new technology in facilitating nervous tissue repair and regeneration.


Asunto(s)
Células Madre Embrionarias/enzimología , Glipicanos/biosíntesis , Células-Madre Neurales/metabolismo , Neuronas/metabolismo , Proteínas Tirosina Fosfatasas Clase 5 Similares a Receptores/biosíntesis , Tenascina/biosíntesis , Animales , Bovinos , Línea Celular , Células Cultivadas , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Ligandos , Ratones , Ratones de la Cepa 129 , Ratones Noqueados , Células-Madre Neurales/citología , Neuronas/citología , Ratas
13.
Microbes Infect ; 12(12-13): 889-99, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20637890

RESUMEN

Malaria is an infectious disease caused by parasites of the genus Plasmodium. This intraerythrocytic protozoan produces hemozoin (HZ), an insoluble crystalline metabolite resulting from the heme detoxification mechanism. This review will focus on HZ biosynthesis and synthetic preparation, but in particular on its effect on host's innate inflammatory responses.


Asunto(s)
Hemoproteínas/inmunología , Inmunidad Innata , Inflamación/inmunología , Plasmodium/inmunología , Hemoproteínas/biosíntesis , Hemoproteínas/síntesis química , Humanos
14.
Brain Res ; 1327: 6-15, 2010 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-20176001

RESUMEN

We have examined the expression and localization patterns of hyaluronan and hyaluronan-binding chondroitin sulfate proteoglycans in neural stem cells and differentiated neural cells derived from mouse embryonic stem cells. Expression of proteoglycans and hyaluronan was weak in the SSEA1-positive embryonic stem cells but increased noticeably after retinoic acid induction to nestin-positive neural stem cells. After subsequent plating, the hyaluronan-binding chondroitin sulfate proteoglycans aggrecan, neurocan, and versican are expressed by cells in both the astrocytic and neuronal lineages. During the time period that hyaluronan was present, it co-localized with each of the hyaluronan-binding proteoglycans studied and was found to be clearly associated with beta-III tubulin-expressing neurons and oligodendrocytes expressing the O4 sulfatide marker. Although proteoglycan expression levels increased to varying degrees following neural differentiation, they did not change noticably during the following 2 weeks in culture, but there was a significant decrease in hyaluronan expression. Our studies therefore demonstrate the expression by neural stem cells and neural cells derived from them of hyaluronan and its associated proteoglycans, thereby providing a necessary foundation for integrating their specific properties into developing strategies for therapeutic applications.


Asunto(s)
Células Madre Embrionarias/fisiología , Ácido Hialurónico/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Proteoglicanos/metabolismo , Agrecanos , Animales , Antineoplásicos/farmacología , Células Cultivadas , Embrión de Mamíferos , Células Madre Embrionarias/efectos de los fármacos , Proteínas Fluorescentes Verdes/genética , Humanos , Ratones , Neurocano , Transfección/métodos , Tretinoina/farmacología , Versicanos
15.
Work ; 33(3): 355-61, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19759434

RESUMEN

A study was conducted to identify possible solutions for redesigning a subway cab in order to improve the posture of drivers working in a restricted space. The approach used included the participation of a working group comprised of operations, maintenance, and engineering managers as well as several drivers. After 6 meetings in which different simulation techniques were used, the working group proposed changes for increasing the available space inside the cab and three seat designs. The involvement of the actors from the three departments affected by the changes, as well as the operators, throughout the process, was a determining factor in the advancement and acceptance of the projects. The fact that 400 cars are currently in service and must be modified means that it will take several years to implement the modifications in the entire fleet.


Asunto(s)
Toma de Decisiones en la Organización , Ergonomía/métodos , Vías Férreas/instrumentación , Lugar de Trabajo/organización & administración , Diseño de Equipo , Humanos , Quebec
16.
PLoS One ; 4(9): e6957, 2009 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-19742308

RESUMEN

Increasing evidence points to an important role for hemozoin (HZ), the malaria pigment, in the immunopathology related to this infection. However, there is no consensus as to whether HZ exerts its immunostimulatory activity in absence of other parasite or host components. Contamination of native HZ preparations and the lack of a unified protocol to produce crystals that mimic those of Plasmodium HZ (PHZ) are major technical limitants when performing functional studies with HZ. In fact, the most commonly used methods generate a heterogeneous nanocrystalline material. Thus, it is likely that such aggregates do not resemble to PHZ and differ in their inflammatory properties. To address this issue, the present study was designed to establish whether synthetic HZ (sHZ) crystals produced by different methods vary in their morphology and in their ability to activate immune responses. We report a new method of HZ synthesis (the precise aqueous acid-catalyzed method) that yields homogeneous sHZ crystals (Plasmodium-like HZ) which are very similar to PHZ in their size and physicochemical properties. Importantly, these crystals are devoid of protein and DNA contamination. Of interest, structure-function studies revealed that the size and shape of the synthetic crystals influences their ability to activate inflammatory responses (e.g. nitric oxide, chemokine and cytokine mRNA) in vitro and in vivo. In summary, our data confirm that sHZ possesses immunostimulatory properties and underline the importance of verifying by electron microscopy both the morphology and homogeneity of the synthetic crystals to ensure that they closely resemble those of the parasite. Periodic quality control experiments and unification of the method of HZ synthesis are key steps to unravel the role of HZ in malaria immunopathology.


Asunto(s)
Hemoproteínas/metabolismo , Sistema Inmunológico/efectos de los fármacos , Plasmodium chabaudi/metabolismo , Animales , Catálisis , Línea Celular , Cristalización , Hemina/química , Humanos , Ratones , Ratones Transgénicos , Microscopía Electrónica de Rastreo , Modelos Biológicos , Relación Estructura-Actividad , Difracción de Rayos X
17.
PLoS Pathog ; 5(8): e1000559, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19696895

RESUMEN

The intraerythrocytic parasite Plasmodium -- the causative agent of malaria -- produces an inorganic crystal called hemozoin (Hz) during the heme detoxification process, which is released into the circulation during erythrocyte lysis. Hz is rapidly ingested by phagocytes and induces the production of several pro-inflammatory mediators such as interleukin-1beta (IL-1beta). However, the mechanism regulating Hz recognition and IL-1beta maturation has not been identified. Here, we show that Hz induces IL-1beta production. Using knockout mice, we showed that Hz-induced IL-1beta and inflammation are dependent on NOD-like receptor containing pyrin domain 3 (NLRP3), ASC and caspase-1, but not NLRC4 (NLR containing CARD domain). Furthermore, the absence of NLRP3 or IL-1beta augmented survival to malaria caused by P. chabaudi adami DS. Although much has been discovered regarding the NLRP3 inflammasome induction, the mechanism whereby this intracellular multimolecular complex is activated remains unclear. We further demonstrate, using pharmacological and genetic intervention, that the tyrosine kinases Syk and Lyn play a critical role in activation of this inflammasome. These findings not only identify one way by which the immune system is alerted to malarial infection but also are one of the first to suggest a role for tyrosine kinase signaling pathways in regulation of the NLRP3 inflammasome.


Asunto(s)
Proteínas Portadoras/fisiología , Hemoproteínas/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Familia-src Quinasas/metabolismo , Animales , Proteínas Reguladoras de la Apoptosis/inmunología , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas Adaptadoras de Señalización CARD , Proteínas de Unión al Calcio/inmunología , Proteínas de Unión al Calcio/metabolismo , Proteínas Portadoras/inmunología , Proteínas Portadoras/metabolismo , Caspasa 1/inmunología , Caspasa 1/metabolismo , Catepsina B/metabolismo , Proteínas del Citoesqueleto/inmunología , Proteínas del Citoesqueleto/metabolismo , Modelos Animales de Enfermedad , Femenino , Proteínas HSP90 de Choque Térmico/metabolismo , Hemoproteínas/inmunología , Hemoproteínas/metabolismo , Humanos , Inflamación/inmunología , Interleucina-1beta/biosíntesis , Interleucina-1beta/metabolismo , Malaria/inmunología , Malaria/metabolismo , Malaria/parasitología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR , Infiltración Neutrófila/inmunología , Fagocitosis , Fosforilación/inmunología , Plasmodium chabaudi/química , Plasmodium chabaudi/metabolismo , Potasio/metabolismo , Proteómica , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/inmunología , Quinasa Syk
18.
J Phys Chem B ; 113(24): 8391-401, 2009 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-19472980

RESUMEN

The condensed crystalline phase of iron(III) protoporphyrin IX either isolated from parasite culture as malaria pigment (hemozoin) or synthetic equivalent hematin anhydride exhibits a solid-state autofluorescence characterized by an excitation maximum of 555 nm and an emission maximum of 577 nm. The excitation spectrum maximum at 555 nm corresponds to the Q(0,0) band in the absorption spectrum which represents the lowest singlet of the material. This suggests that the fluorescent emission is due to the heme condensed phase. The photoluminescence lifetime of tau(f) = 2.7 +/- 0.8 ns as measured at four wavelengths between 550 and 600 nm is in the range of Frankel exciton in porphyrinic condensed phases. The material is shown to have an optical band gap of 2.04 eV characteristic of a semiconductor. Luminescence is markedly dependent upon the degree of hydration and the emission does not seem to be caused by presence of zinc(II) protoporphyrin IX or free-base protoporphyrin IX in the lattice. The autofluorescence can be used for in vivo tracking of hemozoin, for determination of parasitemia levels, and for infection monitoring and possibly for drug screening studies.


Asunto(s)
Fluorescencia , Hemoproteínas/química , Protoporfirinas/química , Animales , Femenino , Hemoproteínas/síntesis química , Macrófagos/química , Ratones , Ratones Endogámicos BALB C , Plasmodium falciparum/química , Factores de Tiempo
19.
Biophys J ; 94(4): L26-8, 2008 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-18065455

RESUMEN

Malaria remains a major health concern worldwide, with 350-500 million cases reported annually in endemic countries. In this study, we report a novel and highly sensitive optical-based detection of malaria-infected blood cells by third harmonic generation (THG) imaging of hemozoin pigment that is naturally deposited by the parasite during its lifecycle. The THG signal from the hemozoin was greater than we have observed in any cell type with signal/noise ratios that reach 1000:1. This method allows a rapid and robust detection of early stage infections of blood cells. The immense nonlinear response of the intrinsic parasitic by-product pigments suggests that automated optical detection by THG could be used for sensitive and rapid screening of parasite infection in blood samples.


Asunto(s)
Eritrocitos/citología , Eritrocitos/parasitología , Hemoproteínas/análisis , Malaria Falciparum/metabolismo , Malaria Falciparum/patología , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Plasmodium falciparum/metabolismo , Animales , Células Cultivadas , Humanos , Aumento de la Imagen/métodos , Malaria Falciparum/parasitología , Plasmodium falciparum/patogenicidad , Sensibilidad y Especificidad
20.
Int J Occup Saf Ergon ; 12(4): 387-97, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17156614

RESUMEN

Research was conducted to identify an ergonomics-based intervention model designed to factor in musculoskeletal disorder (MSD) prevention when library projects are being designed. The first stage of the research involved an a posteriori analysis of 10 recent redesign projects. The purpose of the analysis was to document perceptions about the attention given to MSD prevention measures over the course of a project on the part of 2 categories of employees: librarians responsible for such projects and personnel working in the libraries before and after changes. Subjects were interviewed in focus groups. Outcomes of the analysis can guide our ergonomic assessment of current situations and contribute to a better understanding of the way inclusion or improvement of prevention measures can support the workplace design process.


Asunto(s)
Ergonomía/métodos , Arquitectura y Construcción de Instituciones de Salud/métodos , Bibliotecas , Enfermedades Musculoesqueléticas/prevención & control , Enfermedades Profesionales/prevención & control , Humanos , Factores de Riesgo
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