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1.
J Occup Environ Hyg ; 18(6): 276-287, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34004120

RESUMEN

Home care (HC) aide visits to clients' homes often involve cleaning and disinfecting (C&D) bathrooms. Some ingredients in C&D household products are associated with respiratory illness, including sodium hypochlorite (bleach) and quaternary ammonium compounds (quats). "Green" products may be safer for the environment, however there are limited quantitative evaluations of their respiratory risks. This study assessed airborne concentrations and time profiles of total volatile organic compounds (TVOC) and chlorine generated during typical bathroom cleaning performed by aides using conventional and green products. Aides performed cleaning tasks in a simulated residential bathroom constructed in an environmental air sampling laboratory. A balanced experimental design involved each aide coming to the lab for four visits during which she performed two 20-min cleaning sessions using one of three C&D products (bleach-based, 1-5% sodium hypochlorite by weight; quats-based, 0.1-1% by weight quaternary ammonium compounds; and "green," 0.05% by weight thymol, a component of botanical thyme oil) or distilled water as a control. TVOC and chlorine direct reading instruments were attached to aides with sample inlets located in the breathing zone. Ten-second averages of TVOC and chlorine gas concentrations and instantaneous peak concentrations were recorded for the sessions' duration. TVOC concentrations by methods of C&D application (spraying, streaming, wiping) also were evaluated. The study completed 169 air sampling sessions with 22 aides. The quats-based product generated more than twice the average TVOC concentrations (mean = 1,210 ppb) than the bleach-based (mean = 593 ppb) or green (mean = 498 ppb) products. Each product generated TVOC concentrations that rose rapidly within the first few minutes of application. Spraying produced the highest TVOC exposures, wiping the lowest. Thirteen aides (65%) experienced peak chlorine exposures above the OSHA PEL ceiling limit (1 ppm) when using the bleach-based product. HC aides may experience respiratory hazards from use of conventional or green C&D products formulated with bleach or other respiratory irritants and sprayed in small, poorly ventilated spaces typical of bathrooms. Spraying should be avoided.


Asunto(s)
Auxiliares de Salud a Domicilio , Compuestos Orgánicos Volátiles , Cloro , Femenino , Humanos , Proyectos de Investigación , Cuartos de Baño
2.
Geophys Res Lett ; 47(6): e2019GL085802, 2020 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-32713980

RESUMEN

We use remotely sensed ice velocities in combination with observations of surface elevation and glacier area change to investigate the dynamics of Hagen Bræ, North Greenland in high detail over the last 35 years. From our data, we can establish for the first time that Hagen Bræ is a surge-type glacier with characteristics of both Alaskan- and Svalbard-type surging glaciers. We argue that the observed surge was preconditioned by the glacier geometry and triggered by englacially stored meltwater. At present, the glacier is in a transitional state between active and quiescence phases and is not building up to its pre-surge geometry. We suggest that the glacier is adjusting to the loss of its floating section, general thinning, and changes in fjord conditions that occurred over the study period which are unrelated to the surge behavior. The high temporal resolution of the ice velocity data gives insight to the sub-annual glacier flow.

3.
Osteoarthritis Cartilage ; 25(9): 1496-1504, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28373131

RESUMEN

OBJECTIVE: Understanding the cartilage surface structure, lost in arthritic disease, is essential for developing strategies to effectively restore it. Given that adherence of the lubricating protein, lubricin, to the cartilage surface is critical for boundary lubrication, an interaction with cartilage oligomeric matrix protein (COMP) was investigated. COMP, an abundant cartilage protein, is known to be important for matrix formation. DESIGN: Synovial fluid (SF) from arthritic patients was used to detect possible COMP-lubricin complexes by immunological methods. Recombinant (RC) COMP and lubricin fragments were expressed to characterize this bonding and mass spectrometry employed to specifically identify the cysteines involved in inter-protein disulfide bonds. RESULTS: COMP-lubricin complexes were identified in the SF of arthritic patients by Western blot, co-immunoprecipitation and sandwich ELISA. RC fragment solid-phase binding assays showed that the C-terminal (amino acids (AA) 518-757) of COMP bound non-covalently to the N-terminal of lubricin (AA 105-202). Mass spectrometry determined that although cysteines throughout COMP were involved in binding with lubricin, the cysteines in lubricin were primarily focused to an N-terminal region (AA 64-86). The close proximity of the non-covalent and disulfide binding domains on lubricin suggest a two-step mechanism to strongly bind lubricin to COMP. CONCLUSION: These data demonstrate that lubricin forms a complex network with COMP involving both non-covalent and covalent bonds. This complex between lubricin and the cartilage protein COMP can be identified in the SF of patients with arthritis conditions including osteoarthritis (OA) and rheumatoid arthritis (RA).


Asunto(s)
Artritis/metabolismo , Proteína de la Matriz Oligomérica del Cartílago/metabolismo , Cartílago Articular/metabolismo , Glicoproteínas/metabolismo , Líquido Sinovial/metabolismo , Artritis Reumatoide/metabolismo , Sitios de Unión , Cisteína/metabolismo , Humanos , Osteoartritis/metabolismo , Unión Proteica , Espondiloartritis/metabolismo
4.
Br J Surg ; 102(9): 1133-41, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26042725

RESUMEN

BACKGROUND: Fast-track (FT) programmes are multimodal, evidence-based approaches to optimize patient outcome after surgery. The aim of this study was to evaluate the safety, clinical outcome and patients' experience of a FT programme after pancreaticoduodenectomy (PD) in a high-volume institution in Sweden. METHODS: Consecutive patients undergoing PD were studied before and after implementation of the FT programme. FT changes included earlier mobilization, standardized removal of the nasogastric tube and drain, and earlier start of oral intake. Patient experience was evaluated with European Organization for Research and Treatment of Cancer QLQ-C30 and QLQ-PAN26 questionnaires 2 weeks before and 4 weeks after surgery. RESULTS: Between 2011 and 2014, 100 consecutive patients undergoing PD were studied, of whom 50 received standard care (controls), followed by 50 patients treated after implementation of the FT programme. The nasogastric tube was removed significantly earlier in the FT group, and these patients were able fully to tolerate fluids and solid food sooner after PD. Delayed gastric emptying was significantly reduced in the FT group (26 versus 48 per cent; P = 0.030). Overall morbidity remained unchanged and there were no deaths in either group. Postoperative length of hospital stay was reduced from 14 to 10 days and hospital costs were decreased significantly. Health-related quality-of-life questionnaires showed similar patterns of change, with no significant difference between groups before or after surgery. CONCLUSION: The FT programme after PD was safe. Delayed gastric emptying, hospital stay and hospital costs were all reduced significantly. Although patients were discharged 4 days earlier in the FT group, this did not influence health-related quality of life compared with standard care.


Asunto(s)
Pancreaticoduodenectomía , Cuidados Posoperatorios/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Protocolos Clínicos , Femenino , Costos de Hospital/estadística & datos numéricos , Hospitales de Alto Volumen/estadística & datos numéricos , Humanos , Tiempo de Internación/economía , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud , Pancreaticoduodenectomía/economía , Satisfacción del Paciente/estadística & datos numéricos , Cuidados Posoperatorios/economía , Complicaciones Posoperatorias/economía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Estudios Prospectivos , Calidad de Vida , Encuestas y Cuestionarios , Suecia , Adulto Joven
5.
Biomaterials ; 269: 120641, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33493768

RESUMEN

Critical limb ischemia (CLI) is characterized by the impairment of microcirculation, necrosis and inflammation of the muscular tissue. Although the role of glycans in mediating inflammation has been reported, changes in the glycosylation following muscle ischemia remains poorly understood. Here, a murine CLI model was used to show the increase of high mannose, α-(2, 6)-sialic acid and the decrease of hybrid and bisected N-glycans as glycosylation associated with the ischemic environment. Using this model, the efficacy of an elastin-like recombinamers (ELR) hydrogel was assessed. The hydrogel modulates key angiogenic signaling pathways, resulting in capillary formation, and ECM remodeling. Arterioles formation, reduction of fibrosis and anti-inflammatory macrophage polarization wa also induced by the hydrogel administration. Modulation of glycosylation was observed, suggesting, in particular, a role for mannosylation and sialylation in the mediation of tissue repair. Our study elucidates the angiogenic potential of the ELR hydrogel for CLI applications and identifies glycosylation alterations as potential new therapeutic targets.


Asunto(s)
Elastina , Hidrogeles , Isquemia/terapia , Neovascularización Fisiológica , Animales , Glicosilación , Inflamación , Isquemia/patología , Ratones
6.
Eur Respir J ; 36(1): 96-104, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19897551

RESUMEN

This report concerns the development and validation of two patient-reported outcomes questionnaires developed to assess chronic obstructive pulmonary disease (COPD) patients' ability to perform morning activities and to evaluate their morning symptoms. Based on interviews with COPD patients, the Capacity of Daily Living during the Morning (CDLM) questionnaire and the Global Chest Symptoms Questionnaire (GCSQ) were developed, linguistically validated and incorporated into two multicentre, randomised trials involving a total of 1,100 COPD patients; those trials were registered at ClinicalTrials.gov (NCT00496470 and NCT00542880). Data from these trials were used to determine the reliability, validity and responsiveness of the questionnaires and to derive estimates of minimal important differences (MIDs). Both questionnaires displayed good-to-high reliability (Cronbach's alpha 0.75-0.93). Analysis of convergent validity showed that CDLM and GCSQ scores correlated significantly (p<0.001) with symptoms, health-related quality of life (HRQoL) and use of rescue medication. In both trials, CDLM and GCSQ scores discriminated between patients with different levels of HRQoL, as assessed by the St George's Respiratory Questionnaire for COPD patients (SGRQ-C), but not with disease severity, as assessed by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. A significant improvement in CDLM and GCSQ scores occurred in response to treatment. Estimations of MID scores, corresponding to an SGRQ-C MID of 4, were 0.20 for the CDLM questionnaire and 0.15 for the GCSQ. Both the CDLM questionnaire and the GCSQ are easy-to-use, reliable, responsive, self-administered questionnaires that report on patients' symptoms and ability to perform morning activities.


Asunto(s)
Actividades Cotidianas , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/psicología , Calidad de Vida/psicología , Encuestas y Cuestionarios , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
7.
Bone Marrow Transplant ; 41(4): 399-405, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17982493

RESUMEN

We analysed factors associated with moderate to severe acute GVHD in 111 patients treated with fludarabin-based reduced intensity conditioning (RIC) and allogeneic haematopoietic stem cell transplantation (HSCT). Most patients had a haematological malignancy. Donors were 97 HLA-A, -B and -DRbeta1 identical unrelated and 14 HLA-A, -B or -DRbeta1 allele mismatched unrelated donors. In the univariate analysis, we found ten factors associated with acute GVHD. These were diagnosis (P=0.06), GVHD prophylaxis with combinations other than CsA+MTX (P=0.006), graft nucleated (P<0.001) and CD34 (P<0.001) cell-dose, bidirectional ABO mismatch (P=0.001), conditioning (P=0.002), hospital vs home-care (P=0.06), ATG dose (P<0.001), donor herpes virus serology (P=0.07) and an immunized female donor to male recipient (P=0.05). In the multivariate analysis, three factors remained significant: a high CD34 cell dose (P<0.001), low dose (4 mg/kg) ATG (P<0.001), and an immunized female donor to male recipient (P<0.01). Patients receiving a CD34 cell dose > or =17.0 x 10(6) per kg had a higher incidence of GVHD, 53.7%, compared to 22.3% in patients receiving a lower dose (P=0.002). In patients without any of these risk factors (n=70), the incidence of acute GVHD was 14.1%, while it was 38.0 and 85.0% in patients with one (n=29) or two (n=10) risk factors (P<0.001). We concluded that risk factors for acute GVHD using RIC are similar as using myeloablative conditioning.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Donantes de Tejidos , Acondicionamiento Pretrasplante/efectos adversos , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Acondicionamiento Pretrasplante/métodos , Trasplante Homólogo/efectos adversos
8.
Equine Vet J ; 49(1): 116-123, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26507102

RESUMEN

REASON FOR PERFORMING STUDY: The glycoprotein lubricin contributes to the boundary lubrication of the articular cartilage surface. The early events of osteoarthritis involve the superficial layer where lubricin is synthesised. OBJECTIVES: To characterise the glycosylation profile of lubricin in synovial fluid from horses with osteoarthritis and study secretion and degradation of lubricin in an in vitro inflammation cartilage model. STUDY DESIGN: In vitro study. METHODS: Synovial fluid samples collected from horses with joints with normal articular cartilage and structural osteoarthritic lesions; with and without osteochondral fragments, were analysed for the lubricin glycosylation profiles. Articular cartilage explants were stimulated with or without interleukin-1ß for 25 days. Media samples collected at 3-day intervals were analysed by quantitative proteomics, western blot and enzyme-linked immunosorbent assay. RESULTS: O-glycosylation profiles in synovial fluid revealed both Core 1 and 2 O-glycans, with Core 1 O-glycans predominating. Synovial fluid from normal joints (49.5 ± 1.9%) contained significantly lower amounts of monosialylated Core 1 O-glycans compared with joints with osteoarthritis (53.8 ± 7.8%, P = 0.03) or joints with osteochondral fragments (57.3 ± 8.8%, P = 0.001). Additionally, synovial fluid from normal joints (26.7 ± 6.7%) showed higher amounts of disialylated Core 1 O-glycan than from joints with osteochondral fragments (21.2 ± 4.9%, P = 0.03). A C-terminal proteolytic cleavage site in lubricin was found in synovial fluid from normal and osteochondral fragment joints and in media from interleukin-1ß stimulated and unstimulated articular cartilage explants. CONCLUSIONS: This is the first demonstration of a change in the glycosylation profile of lubricin in synovial fluid from diseased equine joints compared with that from normal joints. We demonstrate an identical proteolytic cleavage site of lubricin both in vitro and in vivo. The reduced sialation of lubricin in synovial fluid from diseased joints may affect the boundary lubricating ability of the superficial layer of articular cartilage and could be one of the early events in the progression of osteoarthritis.


Asunto(s)
Glicoproteínas/metabolismo , Enfermedades de los Caballos/metabolismo , Osteoartritis/veterinaria , Líquido Sinovial/química , Animales , Biomarcadores , Cartílago Articular/patología , Regulación de la Expresión Génica , Glicoproteínas/genética , Enfermedades de los Caballos/genética , Caballos , Osteoartritis/metabolismo
9.
Br J Sports Med ; 39(7): 453-7, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15976170

RESUMEN

OBJECTIVES: As physical activity is promoted as part of a healthy lifestyle, sports injuries are becoming an important public health concern in many countries. The objective of this study is to investigate rates of sports injuries before and after implementation of a WHO Safe Community program. METHODS: Sports injury data were collected pre- and post-implementation from all individuals below 65 years of age during 1 year in the targeted municipality (population 41,000) and in a control municipality (population 26,000). A quasi-experimental design was used and individuals were divided into three categories based on household relationship to the labour market. RESULTS: There were no differences between socio-economic categories regarding pre-intervention injury rates. No statistically significant post-intervention changes in injury rate were observed in the control area or among any females in either area. In the intervention area, a statistically significant (p = 0.011) decrease in injury rate was observed among male members of households in which the vocationally important member was employed. A statistically significant decrease was observed in injuries sustained in team sports among male members of households in which the vocationally important member was employed (p = 0.001) and among members of households in which the vocationally important member was self employed (p<0.05). CONCLUSIONS: The study indicates areas for improvement in the civic network based WHO Safe Community model. The results show that females, participants in individual sports, and members of non-vocationally active households were less affected by the interventions. These facts have to be addressed in planning future community based sports injury prevention programmes and their evaluations.


Asunto(s)
Traumatismos en Atletas/prevención & control , Deportes , Adolescente , Adulto , Anciano , Traumatismos en Atletas/epidemiología , Niño , Preescolar , Recolección de Datos , Promoción de la Salud , Humanos , Persona de Mediana Edad , Seguridad , Factores Socioeconómicos , Suecia/epidemiología , Organización Mundial de la Salud
10.
Int J Epidemiol ; 33(3): 605-11, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15044414

RESUMEN

BACKGROUND: Although social inequality in health has been an argument for community-based injury prevention programmes, intervention outcomes with regard to differences in social standing have not been analysed. The objective of this study was to investigate rates of injuries treated in health-care among members of households at different levels of labour market integration before and after the implementation of a WHO Safe Community programme. METHODS: A quasi-experimental design was used with pre- and post-implementation data collection covering the total populations <65 years of age during one year in the programme implementation municipality (population 41 000) and in a control municipality (population 26 000). Changes in injury rates were studied using prospective registration of all acute care episodes with regard to social standing in both areas during the study periods. RESULTS: Male members of households categorized as not vocationally active displayed the highest pre-intervention injury rates. Also after the intervention, males in households classified as not vocationally active displayed notably elevated injury rates in both the control and study areas. Households in the study area in which the significant member was employed showed a post-intervention decrease in injury rate among both men (P < 0.001) and women (P < 0.01). No statistically significant change was observed in households in which the significant member was self-employed or not vocationally active. In the control area, only an aggregate-level decrease (P < 0.05) among members of households in which the significant member was employed was observed. CONCLUSIONS: The study displayed areas for improvement in the civic network-based WHO Safe Community model. Even though members of non-vocationally active households, in particular men, were at higher pre-intervention injury risk, they were not affected by the interventions. This fact has to be addressed when planning future community-based injury prevention programmes.


Asunto(s)
Servicios de Salud Comunitaria/organización & administración , Empleo , Servicios Preventivos de Salud/organización & administración , Heridas y Lesiones/prevención & control , Adulto , Atención Ambulatoria , Redes Comunitarias , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aceptación de la Atención de Salud , Factores Sexuales , Suecia/epidemiología , Organización Mundial de la Salud , Heridas y Lesiones/epidemiología
11.
J Biochem ; 128(5): 855-67, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11056399

RESUMEN

Glycosphingolipid recognition by two isolectins from Solanum tuberosum was compared by the chromatogram binding assay. One lectin (PL-I) was isolated from potato tubers by affinity chromatography, and identified by MALDI-TOF mass spectrometry as a homodimer with a subunit molecular mass of 63,000. The other (PL-II) was a commercial lectin, characterized as two homodimeric isolectins with subunit molecular masses of 52,000 and 55,000, respectively. Both lectins recognized N-acetyllactosamine-containing glycosphingolipids, but the fine details of their carbohydrate binding specificities differed. PL-II preferentially bound to glycosphingolipids with N-acetyllactosamine branches, as Galbeta4GlcNAcbeta6(Galbeta4GlcNAcbeta3)Galbeta4Glcbeta1C er. PL-I also recognized this glycosphingolipid, but bound equally well to the linear glycosphingolipid Galbeta4GlcNAcbeta3Galbeta4GlcNAcbeta3Galbeta4Glcbeta1Cer. Neolactotetraosylceramide and the B5 pentaglycosylceramide were also bound by PL-I, while other glycosphingolipids with only one N-acetyllactosamine unit were non-binding. Surprisingly, both lectins also bound to lactosylceramide, with an absolute requirement for sphingosine and non-hydroxy fatty acids. The inhibition of binding to both lactosylceramide and N-acetyllactosamine-containing glycosphingolipids by N-acetylchitotetraose suggests that lactosylceramide is also accomodated within the N-acetylchitotetraose/N-acetyllactosamine-binding sites of the lectins. Through docking of glycosphingolipids onto a three-dimensional model of the PL-I hevein binding domain, a Galbeta4GlcNAcbeta3Galbeta4 binding epitope was defined. Furthermore, direct involvement of the ceramide in the binding of lactosylceramide was suggested.


Asunto(s)
Amino Azúcares/metabolismo , Antígenos CD , Péptidos Catiónicos Antimicrobianos , Metabolismo de los Hidratos de Carbono , Lactosilceramidos/metabolismo , Lectinas/aislamiento & purificación , Solanum tuberosum/química , Secuencia de Carbohidratos , Electroforesis en Gel de Poliacrilamida , Lectinas/química , Lectinas/metabolismo , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Datos de Secuencia Molecular , Lectinas de Plantas , Proteínas de Plantas/química , Alineación de Secuencia , Relación Estructura-Actividad
12.
J Mass Spectrom ; 31(5): 560-72, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8799292

RESUMEN

The fraction of sulphated oligosaccharide alditols isolated from mucin glycopeptides of porcine small intestine 'insoluble' mucin complex was analysed by negative-ion fast atom bombardment (FAB) tandem mass spectrometry. Collision-induced dissociation (CID) tandem mass spectra of native and peracetylated species were compared with standards of sulphated monosaccharides. The tandem mass spectra revealed structural information of the carbohydrate sequence and sulphate position. Negative-ion FAB ionization of the peracetylated sulphated oligo-saccharide alditols was at least three times more sensitive than that of the native sulphated oligosaccharide alditols, as revealed by comparing the signal-to-noise ratios, and allowed the detection of eleven compared with six pseudo-molecular ions. Fourteen structures were determined from the CID tandem mass spectra obtained. The main sulphation site was C-6 of an N-acetylglucosamine 6-linked to the N-acetylgalactosaminitol. C-3 of the N-acetylgalactosaminitol could be unsubstituted or extended with a series of up to three monosaccharide residues including blood group H determinants and blood group A determinants. Also, the sulphated N-acetylglucosamine could be further extended. The most abundant structure was a monosulphated trisaccharide with the sequence Gal-->3(SO3-->6GlcNAc-->6)GalNAcol. The sulphation at C-6 of N-acetylglucosamine seems to be a common feature for O-linked oligosaccharides, and has been described both for skeletal keratan sulphates and respiratory mucin oligosaccharides. Low-abundance ions were also detected from oligosaccharides with sulphation at C-3 of an amino sugar residue. This seems to be a novel sulphation site for mucin oligosaccharides.


Asunto(s)
Intestino Delgado/química , Mucinas/química , Oligosacáridos/química , Acetilación , Animales , Secuencia de Carbohidratos , Datos de Secuencia Molecular , Espectrometría de Masa Bombardeada por Átomos Veloces , Sulfatos/química , Porcinos , Terminología como Asunto
13.
Mol Biotechnol ; 1(2): 165-80, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7859159

RESUMEN

High-temperature gas chromatography and gas chromatography-mass spectrometry for the analyses of oligosaccharides derived from glycoproteins or glycosphingolipids has been developed. Permethylated oligosaccharides with up to about 12 sugar residues and masses up to 2500 Daltons can be analyzed. This approach is discussed and exemplified.


Asunto(s)
Cromatografía de Gases/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Glicoconjugados/química , Oligosacáridos/análisis , Animales , Biotecnología , Secuencia de Carbohidratos , Glicopéptidos/química , Glicoproteínas/química , Glicoesfingolípidos/química , Calor , Datos de Secuencia Molecular , Oligosacáridos/química , Polisacáridos/química , Ácidos Siálicos/química
14.
J Chromatogr A ; 854(1-2): 131-9, 1999 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-10497934

RESUMEN

An approach for analyzing sulfated oligosaccharide alditol mixtures by liquid chromatography-electrospray mass spectrometry (LC-ESI-MS) is described. Two columns, an amino-bonded column and a porous graphitized carbon column (PGC) were used. Oligosaccharides were eluted with linear gradients of acetonitrile and water, with 5 mM ammonium hydrogencarbonate or formate buffers at a basic pH. The methods were evaluated on a mixture of sulfated oligosaccharide alditols prepared from mucin glycoproteins from pig stomach. Results from LC-ESI-MS of the mixture were compared with the structural information obtained by high energy collision fragmentation using fast atom bombardment tandem mass spectrometry (FAB-MS-MS). The separation ability of the two columns was also tested using a more complex mixture of sulfated oligosaccharides from pig colon, where several isomers were detected. The potential use of in-source collision-induced dissociation (CID) to gain sequence information of sulfated oligosaccharides was also evaluated. The major fragment ions obtained by in-source CID of the trisaccharide Hex-3HexNAcol6-HexNAc6-SO3 were sufficient for assigning the oligosaccharide sequence and the position of the sulfate group within the monosaccharide moiety. The LC-ESI-MS approach should be a valuable tool for characterization of mucin glycosylation and alterations during pathological conditions.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Glicoproteínas/química , Espectrometría de Masas/métodos , Mucinas/química , Oligosacáridos/análisis , Animales , Secuencia de Carbohidratos , Datos de Secuencia Molecular , Ácidos Sulfúricos/química , Porcinos
15.
Mutat Res ; 260(1): 39-46, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-2027339

RESUMEN

Condensates of smoke from titanium dioxide/hexachloroethane and zinc/hexachloroethane pyrotechnic mixtures were investigated for their potential to produce genetic damage in the tester strains TA98, TA100, TA1535 and TA1537 of Salmonella typhimurium and in the mouse bone marrow micronucleus assay. Both smoke condensates contained several chlorinated hydrocarbons among which tetrachloroethylene, hexachloroethane, hexachlorobutadiene and hexachlorobenzene were identified by GC/MS. Condensate of smoke from titanium dioxide/hexachloroethane showed a dose-related positive response in the Salmonella assay with strains TA98 and TA100 in the absence of metabolic activation from rat liver S9 fraction. Both smoke condensates were negative in the micronucleus assay but produced a small but significant depression of erythropoietic activity. The results indicate that smoke condensate from titanium dioxide/hexachloroethane mixtures contains unidentified compound(s) that may be considered mutagenic in the Salmonella assay.


Asunto(s)
Antihelmínticos/toxicidad , ADN/efectos de los fármacos , Etano/análogos & derivados , Hidrocarburos Clorados/toxicidad , Humo/efectos adversos , Titanio/toxicidad , Zinc/toxicidad , Animales , Médula Ósea/efectos de los fármacos , Etano/toxicidad , Femenino , Cromatografía de Gases y Espectrometría de Masas , Masculino , Ratones , Ratones Endogámicos CBA , Pruebas de Micronúcleos , Pruebas de Mutagenicidad , Salmonella typhimurium
16.
Science ; 334(6052): 69-72, 2011 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-21980105

RESUMEN

We report the detection of pulsed gamma rays from the Crab pulsar at energies above 100 giga-electron volts (GeV) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) array of atmospheric Cherenkov telescopes. The detection cannot be explained on the basis of current pulsar models. The photon spectrum of pulsed emission between 100 mega-electron volts and 400 GeV is described by a broken power law that is statistically preferred over a power law with an exponential cutoff. It is unlikely that the observation can be explained by invoking curvature radiation as the origin of the observed gamma rays above 100 GeV. Our findings require that these gamma rays be produced more than 10 stellar radii from the neutron star.

18.
Science ; 325(5939): 444-8, 2009 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-19574351

RESUMEN

The accretion of matter onto a massive black hole is believed to feed the relativistic plasma jets found in many active galactic nuclei (AGN). Although some AGN accelerate particles to energies exceeding 10(12) electron volts and are bright sources of very-high-energy (VHE) gamma-ray emission, it is not yet known where the VHE emission originates. Here we report on radio and VHE observations of the radio galaxy Messier 87, revealing a period of extremely strong VHE gamma-ray flares accompanied by a strong increase of the radio flux from its nucleus. These results imply that charged particles are accelerated to very high energies in the immediate vicinity of the black hole.

19.
Mucosal Immunol ; 1(3): 183-97, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-19079178

RESUMEN

The mucosal tissues of the gastrointestinal, respiratory, reproductive, and urinary tracts, and the surface of the eye present an enormous surface area to the exterior environment. All of these tissues are covered with resident microbial flora, which vary considerably in composition and complexity. Mucosal tissues represent the site of infection or route of access for the majority of viruses, bacteria, yeast, protozoa, and multicellular parasites that cause human disease. Mucin glycoproteins are secreted in large quantities by mucosal epithelia, and cell surface mucins are a prominent feature of the apical glycocalyx of all mucosal epithelia. In this review, we highlight the central role played by mucins in accommodating the resident commensal flora and limiting infectious disease, interplay between underlying innate and adaptive immunity and mucins, and the strategies used by successful mucosal pathogens to subvert or avoid the mucin barrier, with a particular focus on bacteria.


Asunto(s)
Infecciones/inmunología , Mucinas/metabolismo , Membrana Mucosa/inmunología , Membrana Mucosa/microbiología , Animales , Humanos , Inmunidad Activa , Inmunidad Innata , Inmunidad Mucosa , Infecciones/microbiología , Infecciones/virología , Mucinas/biosíntesis , Mucinas/química , Conformación Proteica
20.
Clin Allergy Immunol ; 19: 305-21, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17153022

RESUMEN

By clinical experience, rhinitis has been suggested as caused by some endocrine disorders, but the evidence for this is vague, and the few descriptions almost anecdotal. Rhinitis of the menstrual cycle has been more described, although a solid picture is still lacking. Pregnancy rhinitis is therefore so far the only clearly defined "hormonal rhinitis." However, the cause of pregnancy rhinitis is not simply estrogen or progesterone, but seems multifactorial, and may possibly be associated with the PGH. Treatment consists mainly of information, physiological measures, and nasal saline washings.


Asunto(s)
Ciclo Menstrual/fisiología , Complicaciones del Embarazo/etiología , Rinitis/etiología , Acromegalia/complicaciones , Diagnóstico Diferencial , Femenino , Humanos , Hipotiroidismo/complicaciones , Embarazo , Rinitis/terapia
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