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1.
Soft Matter ; 10(26): 4711-6, 2014 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-24854899

RESUMEN

The present study is based on the idea of understanding the rupture of films in metal foams by studying free standing metallic films as a model system. Liquid dynamics, the velocity of the rupturing material as well as the behaviour of ceramic particles inside the melt were analysed optically ex situ and by synchrotron X-ray radiography in situ. It was found that the resistance of films to rupture is mainly based on the interaction between solid particles and an immobile oxide skin, the formation of which depends on the oxygen content of the surrounding atmosphere and the presence of magnesium.

2.
Microbiology (Reading) ; 158(Pt 12): 2903-2916, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23082034

RESUMEN

Dental caries is a common infectious disease associated with acidogenic and aciduric bacteria, including Streptococcus mutans. Organisms that cause cavities form recalcitrant biofilms, generate acids from dietary sugars and tolerate acid end products. It has recently been recognized that micro-organisms can produce functional amyloids that are integral to biofilm development. We now show that the S. mutans cell-surface-localized adhesin P1 (antigen I/II, PAc) is an amyloid-forming protein. This conclusion is based on the defining properties of amyloids, including binding by the amyloidophilic dyes Congo red (CR) and Thioflavin T (ThT), visualization of amyloid fibres by transmission electron microscopy and the green birefringent properties of CR-stained protein aggregates when viewed under cross-polarized light. We provide evidence that amyloid is present in human dental plaque and is produced by both laboratory strains and clinical isolates of S. mutans. We provide further evidence that amyloid formation is not limited to P1, since bacterial colonies without this adhesin demonstrate residual green birefringence. However, S. mutans lacking sortase, the transpeptidase enzyme that mediates the covalent linkage of its substrates to the cell-wall peptidoglycan, including P1 and five other proteins, is not birefringent when stained with CR and does not form biofilms. Biofilm formation is inhibited when S. mutans is cultured in the presence of known inhibitors of amyloid fibrillization, including CR, Thioflavin S and epigallocatechin-3-gallate, which also inhibited ThT uptake by S. mutans extracellular proteins. Taken together, these results indicate that S. mutans is an amyloid-forming organism and suggest that amyloidogenesis contributes to biofilm formation by this oral microbe.


Asunto(s)
Adhesinas Bacterianas/metabolismo , Amiloide/metabolismo , Streptococcus mutans/metabolismo , Amiloide/ultraestructura , Benzotiazoles , Biopelículas/crecimiento & desarrollo , Rojo Congo/metabolismo , Microscopía Electrónica de Transmisión , Coloración y Etiquetado , Streptococcus mutans/fisiología , Tiazoles/metabolismo
3.
Transfusion ; 51(6): 1154-62, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21175646

RESUMEN

BACKGROUND: The efficacy of granulocyte transfusions in patients with HLA alloimmunization is uncertain. A flow cytometric assay using dihydrorhodamine 123 (DHR), a marker for cellular NADPH oxidase activity, was used to monitor the differential survival of transfused oxidase-positive granulocytes in alloimmunized patients with chronic granulomatous disease (CGD). STUDY DESIGN AND METHODS: Ten patients with CGD and serious infections were treated with daily granulocyte transfusions derived from steroid and granulocyte-colony-stimulating factor-stimulated donors. The proportion of neutrophils with intact oxidase activity was quantitated by DHR fluorescence on samples drawn before and 1 hour after transfusion. The incidence of acute transfusion reactions was correlated with the results of DHR fluorescence and biweekly HLA serologic screening assays. RESULTS: Eight of 10 patients experienced acute adverse reactions in association with granulocyte transfusions. Four had only chills and/or fever, and four experienced respiratory compromise; all eight exhibited HLA alloimmunization. Mean (± SD) oxidase-positive cell recovery was 19.7 ± 17.4% (n = 15 transfusions) versus 0.95 ± 1.59% (n = 16) in the absence and presence of HLA allosensitization, respectively (p < 0.01). Greater than 1% in vivo recovery of DHR-enhancing donor granulocytes was strongly correlated with lack of HLA alloimmunization. CONCLUSION: The ability to detect DHR-positive donor granulocytes by flow cytometry is strongly correlated with absence of HLA alloimmunization and lack of acute reactions to granulocyte transfusions in patients with CGD. If HLA antibodies are present and the survival of donor granulocytes is low by DHR analysis, transfusions should be discontinued, avoiding a therapy associated with high risk and unclear benefit.


Asunto(s)
Granulocitos/trasplante , Enfermedad Granulomatosa Crónica/terapia , Transfusión de Leucocitos/métodos , Adolescente , Niño , Preescolar , Femenino , Citometría de Flujo , Humanos , Masculino , Neutrófilos/citología , Adulto Joven
4.
J Lipid Res ; 51(1): 182-91, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19546342

RESUMEN

Fatty acid desaturases (FADS) play an important role in the formation of omega-6 and omega-3 highly unsaturated fatty acids (HUFAs). The composition of HUFAs in the human metabolome is important for membrane fluidity and for the modulation of essential physiological functions such as inflammation processes and brain development. Several recent studies reported significant associations of single nucleotide polymorphisms (SNPs) in the human FADS gene cluster with HUFA levels and composition. The presence of the minor allele correlated with a decrease of desaturase reaction products and an accumulation of substrates. We performed functional studies with two of the associated polymorphisms (rs3834458 and rs968567) and showed an influence of polymorphism rs968567 on FADS2 promoter activity by luciferase reporter gene assays. Electrophoretic mobility shift assays proved allele-dependent DNA-binding ability of at least two protein complexes to the region containing SNP rs968567. One of the proteins binding to this region in an allele-specific manner was shown to be the transcription factor ELK1 (a member of ETS domain transcription factor family). These results indicate that rs968567 influences FADS2 transcription and offer first insights into the modulation of complex regulation mechanisms of FADS2 gene transcription by SNPs.


Asunto(s)
Ácido Graso Desaturasas/genética , Polimorfismo de Nucleótido Simple , Proteína Elk-1 con Dominio ets/metabolismo , Alelos , Células HeLa , Humanos , PPAR alfa/metabolismo , Regiones Promotoras Genéticas , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT3/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Proteína Elk-1 con Dominio ets/genética
5.
Ann Occup Hyg ; 54(1): 8-22, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19759172

RESUMEN

The aim of this study was to measure the levels of nickel in the skin contaminant layer of workers involved in specific processes and tasks within the primary nickel production and primary nickel user industries. Dermal exposure samples were collected using moist wipes to recover surface contamination from defined areas of skin. These were analysed for soluble and insoluble nickel species. Personal samples of inhalable dust were also collected to determine the corresponding inhalable nickel exposures. The air samples were analysed for total inhalable dust and then for soluble, sulfidic, metallic, and oxidic nickel species. The workplace surveys were carried out in five different workplaces, including three nickel refineries, a stainless steel plant, and a powder metallurgy plant, all of which were located in Europe. Nickel refinery workers involved with electrolytic nickel recovery processes had soluble dermal nickel exposure of 0.34 microg cm(-2) [geometric mean (GM)] to the hands and forearms. The GM of soluble dermal nickel exposure for workers involved in packing nickel salts (nickel chloride hexahydrate, nickel sulphate hexahydrate, and nickel hydroxycarbonate) was 0.61 microg cm(-2). Refinery workers involved in packing nickel metal powders and end-user powder operatives in magnet production had the highest dermal exposure (GM = 2.59 microg cm(-2) soluble nickel). The hands, forearms, face, and neck of these workers all received greater dermal nickel exposure compared with the other jobs included in this study. The soluble nickel dermal exposures for stainless steel production workers were at or slightly above the limit of detection (0.02 microg cm(-2) soluble nickel). The highest inhalable nickel concentrations were observed for the workers involved in nickel powder packing (GM = 0.77 mg m(-3)), although the soluble component comprised only 2% of the total nickel content. The highest airborne soluble nickel exposures were associated with refineries using electrolytic processes for nickel recovery (GM = 0.04 mg m(-3) total nickel, containing 82% soluble nickel) and those jobs involving contact with soluble nickel compounds (GM = 0.02 mg m(-3) total nickel content, containing 76% soluble nickel). The stainless steel workers were exposed to low concentrations of relatively insoluble airborne nickel species (GM = 0.03 mg m(-3) total nickel, containing 1% soluble nickel). A statistically significant correlation was observed between dermal exposures for all anatomical areas across all tasks. In addition, the dermal and inhalable (total) nickel exposures were similarly associated. Overall, dermal exposures to nickel, nickel compounds, and nickel alloys were relatively low. However, exposures were highly variable, which can be explained by the inconsistent use of personal protective equipment, varying working practices, and different standards of automation and engineering controls within each exposure category.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Metalurgia , Níquel/análisis , Exposición Profesional/análisis , Absorción Cutánea , Contaminantes Ocupacionales del Aire/normas , Contaminación del Aire Interior/estadística & datos numéricos , Aleaciones/análisis , Polvo/análisis , Monitoreo del Ambiente , Europa (Continente) , Humanos , Exposición por Inhalación/análisis , Exposición por Inhalación/normas , Exposición por Inhalación/estadística & datos numéricos , Límite de Detección , Níquel/normas , Exposición Profesional/estadística & datos numéricos , Equipos de Seguridad/estadística & datos numéricos , Medición de Riesgo , Solubilidad , Oligoelementos/análisis , Lugar de Trabajo/estadística & datos numéricos
6.
Dalton Trans ; 44(22): 10508-15, 2015 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-25986391

RESUMEN

The aqueous speciation of selenium(iv) was elucidated by a combined approach applying quantum chemical calculations, infrared (IR), Raman, and (77)Se NMR spectroscopy. The dimerization of hydrogen selenite (HSeO3(-)) was confirmed at concentrations above 10 mmol L(-1) by both IR and NMR spectroscopy. Quantum chemical calculations provided the assignment of vibrational bands observed to specific molecular modes of the (HSeO3)2(2-) ion. The results presented will provide a better understanding of the chemistry of aqueous Se(iv) which is of particular interest for processes occurring at mineral/water interfaces.


Asunto(s)
Selenio/química , Dimerización , Espectroscopía de Resonancia Magnética , Soluciones , Espectrofotometría Infrarroja , Espectrometría Raman
7.
Anticancer Res ; 17(4B): 3129-31, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9329618

RESUMEN

In the present study the modulatory effects of inflammatory cytokines, interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma), on CA-125 release in established ovarian cancer cell lines and in human peritoneal mesothelial cells (HPMC) both grown as monolayers, were investigated. The purity of mesothelial cell cultures were confirmed by the positivity of the cells for vimentin and cytokeratins 8 and 18, and their negativity for markers CD34 and CD68, thus excluding contamination by endothelial cells and macrophages. The preliminary results of CA-125 measurements in the culture medium clearly indicated differences in the pattern of CA-125 expression and release between normal and malignant cells under the influence of inflammatory cytokines. Furthermore, it seems that normal mesothelial cells play a crucial role as a source of CA-125 found in ascitic fluid or in pleural effusions and possibly even in the serum since secretion of this tumor marker into the culture medium was found to be significantly higher in HPMC than in ovarian cancer cells.


Asunto(s)
Antígeno Ca-125/metabolismo , Citocinas/farmacología , Neoplasias Ováricas/metabolismo , Células Cultivadas , Epitelio/metabolismo , Femenino , Humanos , Interferón gamma/farmacología , Interleucina-1/farmacología , Cavidad Peritoneal/citología , Factor de Necrosis Tumoral alfa/farmacología
8.
Arch Dermatol Res ; 289(5): 243-50, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9164632

RESUMEN

The purpose of the study was to investigate the cytokine gene expression patterns and immunohistochemical characteristics of genitoanal warts in order to obtain a clue as to the immunological mechanisms possibly relevant for wart regression or persistence. We analysed surgically removed warts from 11 patients, 2 of whom were immunosuppressed. Lesions of five of the nine otherwise healthy individuals were additionally treated with intralesional interferon-gamma (IFN gamma) prior to surgery. Invasion of CD4+ T cells into the papillomas and HLA-DR and ICAM-1 expression on keratinocytes were found in two otherwise healthy patients and were intensified by intralesional IFN gamma in four of five patients. The mRNA expression patterns in seven of eight non-recurrent warts were compatible with a predominant TH1 or mixed TH1/TH2 cytokine profile. In contrast, in recalcitrant warts of three patients (one healthy, two immunocompromised) histological signs of immunore-activity and TH1-like cytokine mRNA expression were not detected. In recurrent warts of a renal transplant patient, IL-4 and IL-5 mRNA expression was repeatedly found suggesting a predominant TH2 response. In conclusion, immunoreactivity to genitoanal warts such as T-cell infiltration, HLA-DR and ICAM-1 expression was associated with a predominant TH1 or mixed TH1/ TH2 cytokine mRNA expression profile.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Condiloma Acuminado/inmunología , Citocinas/biosíntesis , Antígenos HLA-DR/biosíntesis , Molécula 1 de Adhesión Intercelular/biosíntesis , Interferón gamma/farmacología , Adulto , Linfocitos T CD8-positivos/inmunología , Condiloma Acuminado/genética , Condiloma Acuminado/terapia , Citocinas/genética , Regulación de la Expresión Génica , Humanos , Interferón gamma/uso terapéutico , Interferones/biosíntesis , Interferones/genética , Interleucinas/biosíntesis , Interleucinas/genética , Queratinocitos/metabolismo , Masculino , Persona de Mediana Edad , ARN Mensajero/genética , ARN Mensajero/metabolismo , Células TH1/inmunología , Células Th2/inmunología , Factores de Crecimiento Transformadores/biosíntesis , Factores de Crecimiento Transformadores/genética , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/genética
9.
J Psychosom Res ; 46(4): 391-4, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10340239

RESUMEN

The central purpose of this investigation was to detect incidence and influencing factors on early postnatal depressive mood in a large hospital sample. By means of an interview we acquired information on sociodemographic data, physical and psychiatric anamnesis, and obstetric and psychologic variables. The Edinburgh Postnatal Depression Scale (EPDS) served to determine the depressive mood of our patients. The interview was carried out on 1250 women at two postnatal wards 5 days after delivery. According to the results of the German validation of the EPDS, where a cutoff of 9/10 indicates at least mild depressive disorder, the whole sample was divided into group A (EPDS score < or = 9; n = 996, 79.7%) and group B (EPDS score > or = 10; n = 254, 20.3%). Early postnatal depressive mood, as assessed by the EPDS, appeared with 20% of all women taking part in our investigation on the fifth postnatal day. Subjective measurements such as high childbirth burden, elevated trait anxiety, low life satisfaction and lower social class, and low birth weight of the infant seem to be of predominant relevance for early postnatal depressive mood.


Asunto(s)
Depresión Posparto/epidemiología , Escalas de Valoración Psiquiátrica/normas , Adulto , Ansiedad/diagnóstico , Ansiedad/epidemiología , Ansiedad/psicología , Austria/epidemiología , Depresión Posparto/diagnóstico , Depresión Posparto/psicología , Femenino , Humanos , Incidencia , Recién Nacido de Bajo Peso/psicología , Recién Nacido , Paridad , Embarazo , Calidad de Vida , Análisis de Regresión , Factores de Riesgo , Muestreo , Factores Socioeconómicos , Estadísticas no Paramétricas
10.
Environ Pollut ; 92(2): 193-201, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-15091399

RESUMEN

Total mercury (HgT), methylmercury (MeHg), and other operationally defined Hg species were determined on water samples collected from a river-reservoir system impacted by historic mine wastes. Simultaneously, a comprehensive study was undertaken to determine the influence of some major physico-chemical parameters on the fate of Hg within the system. Total Hg levels showed an increase from background concentrations of 4 ng liter(-1) upstream of mining activity, to peak values of 1500-2100 ng liter(-1) downstream of Hg contaminated mine tailings piles. MeHg concentrations varied from 0.1 to 7 ng liter(-1) in surface waters. In both cases, peak values were associated with the highest concentrations of total suspended solids (TSS). Particulate Hg (HgP) was typically >50% of HgT and increased downstream. The dissolved fraction of MeHg (MeHgD) always constituted a large portion of total methylmercury (MeHgT). The [MeHgT]/[HgT] ratio decreased downstream suggesting either a high percentage of inorganic Hg input from point sources, or low specific rates of MeHg production within the aquatic system. The latter could be due to the combined effects on microbial populations of both high levels of Hg concentrations found in water and sediments, and other factors related to the aqueous geochemistry of the system. Concentrations of HgT in the water column appeared to be enhanced by inputs of contaminated particles from the watershed during spring snow melt. In the reservoir, significant losses of Hg from the water column were observed. In addition to losses of Hg bound to particles by sedimentation, the removal through volatilization of dissolved gaseous Hg could be an important pathway.

11.
J Reprod Med ; 45(1): 42-4, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10664947

RESUMEN

BACKGROUND: Melanotic lesions of the vagina are very rare; clinically, most are suspected to be malignant melanomas. Occasional benign cases, however, require differential diagnostic consideration. We report a case of multiple (benign) blue nevi of the vagina. CASE: A 51-year-old woman presented with bluish black macules irregularly distributed throughout the vagina. Biopsies revealed pigmented cells in the dermis that proved to be melanocytes. The patient received no therapy. The lesions remained unchanged in the follow-up period. CONCLUSION: Multiple blue nevi could be a differential diagnosis for malignant melanoma of the vagina. Our patient showed no malignant transformation over a 29-year period. Therapy for blue nevi in the vagina does not require complete excision.


Asunto(s)
Nevo Azul/diagnóstico , Neoplasias Cutáneas/diagnóstico , Vagina , Diagnóstico Diferencial , Femenino , Humanos , Melanocitos/patología , Melanoma , Persona de Mediana Edad , Nevo Azul/patología , Neoplasias Cutáneas/patología
12.
Wien Klin Wochenschr ; 110(10): 370-5, 1998 May 22.
Artículo en Alemán | MEDLINE | ID: mdl-9654692

RESUMEN

OBJECTIVE: Investigations in recent years confirm the importance of "anger coping-behaviour" for women suffering from different diseases such as migraine, high blood pressure and coronary heart disease. The hypothesis for this investigation was that "anger-in" coping (anger-suppression) is a possible causal factor in the premenstrual syndrome. METHODS: Data analysis was undertaken on 38 patients (average age 32 years) fulfilling the inclusion criteria. The Menstrual Distress Questionnaire (MDQ) was used for measuring the intensity of premenstrual symptoms. As a result of a cluster analysis of MDQ scores, the 38 patients were divided into 3 subgroups (group 1: mild symptoms, n = 16; group 2: moderate symptoms, n = 10; groups 3: severe symptoms, n = 12). The 3 groups were compared by using different questionnaires regarding the variables anger, attitudes to menarche and menstrual bleeding, anxiety and depression. Additionally, sociodemographic data were obtained and a daily record taken for 2 days premenstrually and 5 day postmenstrually of subjective replies to a standardized protocol. RESULTS: Contrary to our expectations the results showed no significant differences for "anger coping" between the 3 subgroups. Increased daily stress (professional and familial double load) statistically significantly influenced the intensity of premenstrual symptoms. Additional significant factors were a general tendency towards somatization disorder, a negative attitude toward menarche and menstrual bleeding, as well as a tendency to depressive mood in patients with severe premenstrual symptoms. CONCLUSION: Emotional disorders (anger, anxiety) showed less influence on the premenstrual syndrome in the investigated women than daily stress and medical anamnesis.


Asunto(s)
Adaptación Psicológica , Ira , Síndrome Premenstrual/psicología , Adulto , Femenino , Identidad de Género , Humanos , Inventario de Personalidad , Síndrome Premenstrual/diagnóstico , Trastornos Somatomorfos/diagnóstico , Trastornos Somatomorfos/psicología , Estrés Psicológico/complicaciones
13.
Gynakol Geburtshilfliche Rundsch ; 35 Suppl 1: 25-31, 1995.
Artículo en Alemán | MEDLINE | ID: mdl-8672922

RESUMEN

OBJECTIVE: A serological assay for genital HPV infection would provide important additional information to HPV DNA diagnostic methods, since it would evaluate prior exposure to the viruses, detect significant systemic immunologic response to virus infection, and could be performed in most clinical laboratories. METHODS: Serum samples from three groups of patients attending a gynecology clinic were analysed by direct ELISA for specific IgG antibodies to baculovirus-expressed HPV-6 and BPV-1-L1-VLPs. RESULTS: Positive IgG reactivity to HPV-6-L1-VLPs were 4/72 (6%) in a control group, 28/73 (38%) in a condyloma group and 17/62 (17%) in cervical intraepithelial neoplasia patients. Individual IgG ELISA values of condyloma and CIN patients for HPV-6-L1-VLPs demonstrated no correlation to results with BPV-1-L1-VLPs. CONCLUSIONS: These data show that HPV-6-L1-VLPs are effective antigens for serological studies and can detect species specific antibodies with important implications for diagnosis, epidemiology, insights to natural course of disease, prognosis and evaluation of vaccination.


Asunto(s)
Anticuerpos Antivirales/sangre , Proteínas de la Cápside , Ensayo de Inmunoadsorción Enzimática , Neoplasias de los Genitales Femeninos/diagnóstico , Proteínas Oncogénicas Virales/inmunología , Papillomaviridae/inmunología , Infecciones por Papillomavirus/diagnóstico , Infecciones Tumorales por Virus/diagnóstico , Adolescente , Adulto , Especificidad de Anticuerpos/inmunología , Cápside/inmunología , Condiloma Acuminado/diagnóstico , Condiloma Acuminado/inmunología , Femenino , Neoplasias de los Genitales Femeninos/inmunología , Humanos , Inmunoglobulina G/sangre , Persona de Mediana Edad , Infecciones por Papillomavirus/inmunología , Infecciones Tumorales por Virus/inmunología , Proteínas Virales
14.
J Colloid Interface Sci ; 416: 133-8, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-24370412

RESUMEN

The surface speciation of uranium(VI) on maghemite (γ-Fe2O3) was elucidated at the spectroscopic level for the first time. By means of in situ ATR FT-IR measurements, the formation of uranium(VI) outer-sphere complexes was revealed under anoxic conditions and in ambient atmosphere at mildly acid conditions. This type of complexation was verified by the frequency of the ν3(UO2) mode observed for the surface species, the impact of the ionic strength of the background electrolyte on U(VI) sorption and by the high reversibility of the sorption process monitored by on line spectroscopy. The impact of carbonate ions from atmospherically derived CO2 on U(VI) sorption on maghemite was investigated. Although the surface speciation of the carbonate ions presumably change from a monodentate coordination on maghemite to a bidentate coordination in the ternary sorption system, the U(VI) speciation is not changed. A contrasting juxtaposition of comparable results obtained from maghemite and ferrihydrite reveals a basically different type of U(VI) complexation, namely outer and inner spheric coordination.

15.
J Gerontol Nurs ; 12(11): 4-7, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3640788
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