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1.
Sci Rep ; 14(1): 2670, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302500

RESUMEN

A small chlorite vial, discovered among numerous artifacts looted and recovered in the Jiroft region of Kerman province, southeastern Iran, contains a deep red cosmetic preparation that is likely a lip-coloring paint or paste. Through analytical research involving XRD (X-ray diffraction), SEM-EDS (scanning electron microscopy-energy-dispersive spectroscopy), and HPLC-MS (high-performance liquid chromatography-mass spectrometry) analyses, the mineral components of the reddish substance were identified as hematite, darkened with manganite and braunite, and traces of galena and anglesite, mixed with vegetal waxes and other organic substances. The mixture, thus observed, bears a striking resemblance to the recipes of contemporary lipsticks. We also report the first radiocarbon date ever obtained from a Bronze age cosmetic in the ancient Near East: results place the pigment in the early 2nd millennium BCE, a date compatible with several mentions of the powerful eastern-iranian civilization of Marhasi in coeval cuneiform texts of Mesopotamia, as well as with its currently emerging archaeological picture.

2.
Inhal Toxicol ; 21(2): 133-40, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19012058

RESUMEN

For pathologists, pneumologists, and occupational and environmental physicians it is relevant to know silica levels in lung tissue to better define limits of exposure. Environmental Scanning Electron Microscopy (ESEM) has been employed to detect silica particles and to compare silica levels in subjects with and without Lung Cancer (LC). We investigated 25 paraffin-embedded tissue samples of patients with LC adenocarcinoma, and 20 fresh samples of subjects without LC deceased for extra-pulmonary diseases. Silica levels were quantified considering the Number of Spots of silica particles (NS), and the Number of Positive Zones (NPZ) in which there was at least one spot. Levels of NS and NPZ were assessed with Poisson-type regression models, and in two samples of silica-exposed workers with LC the performance of models were evaluated. LC patients displayed higher silica levels, as compared to controls; smoking, age and gender had no significant effects on this relationship. Values of NS and NPZ for the exposed workers were in agreement with model estimates. The fitted model between NS and NPZ might be useful in evaluating new observations and in the development of threshold limit values of silica in biological tissues. ESEM is a rapid, simple and valid tool for the determination of silica levels in lung tissues.


Asunto(s)
Adenocarcinoma/patología , Exposición por Inhalación/análisis , Neoplasias Pulmonares/patología , Pulmón/patología , Dióxido de Silicio/análisis , Adenocarcinoma/etiología , Adulto , Anciano , Anciano de 80 o más Años , Interpretación Estadística de Datos , Femenino , Humanos , Exposición por Inhalación/efectos adversos , Neoplasias Pulmonares/etiología , Masculino , Microscopía Electrónica de Rastreo , Persona de Mediana Edad , Tamaño de la Partícula , Factores de Riesgo , Dióxido de Silicio/toxicidad , Fumar/efectos adversos
3.
Cell Death Discov ; 5: 57, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30701089

RESUMEN

Nephrocalcinosis is a clinicopathological entity characterized by microscopic calcium crystals in the renal parenchyma, within the tubular lumen or in the interstitium. Crystal binding to tubular cells may be the cause underlying nephrocalcinosis and nephrolithiasis. Pathological circumstances, such as acute cortical necrosis, may induce healthy cells to acquire a crystal-binding phenotype. The present study aimed to investigate whether human renal proximal tubular cells (HK-2 cells) can form calcium phosphate deposits under osteogenic conditions, and whether apoptosis and/or osteogenic-like processes are involved in cell calcification. HK-2 cells were cultured in standard or osteogenic medium for 1, 5, and 15 days. Von Kossa staining and ESEM were used to analyze crystal deposition. Apoptosis was investigated, analyzing caspase activation by in-cell Western assay, membrane translocation of phosphotidylserine by annexin V-FITC/propidium iodide staining, and DNA fragmentation by TUNEL assay. qRT/PCR, immunolabeling and cytochemistry were performed to assess osteogenic activation (Runx2, Osteonectin, Osteopontin and ALP), and early genes of apoptosis (BAX, Bcl-2). HK-2 cell mineralization was successfully induced on adding osteogenic medium. Calcium phosphate deposition increased in a time-dependent manner, and calcified cell aggregates exhibited characteristic signs of apoptosis. At 15 days, calcifying HK-2 cells revealed osteogenic markers, such as Runx2, ALP, osteonectin and osteopontin. Monitoring the processes at 1, 5, and 15 days showed apoptosis starting already after 5 days of osteogenic induction, when the first small calcium phosphate crystals began to appear on areas where cell aggregates were in apoptotic conditions. The cell death process proved caspase-dependent. The importance of apoptosis was reinforced by the time-dependent increase in BAX expression, starting from day 1. These findings strongly support the hypothesis that apoptosis triggered HK-2 calcification even before any calcium phosphate crystal deposition or acquisition of an osteogenic phenotype.

4.
Biosci Rep ; 38(1)2018 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-29208768

RESUMEN

Nephrocalcinosis involves the deposition of microscopic crystals in the tubular lumen or interstitium. While the clinical, biochemical, and genetic aspects of the diseases causing nephrocalcinosis have been elucidated, little is known about the cellular events in this calcification process. We previously reported a phenomenon involving the spontaneous formation of Ca2PO4 nodules in primary papillary renal cells from a patient with medullary nephrocalcinosis harboring a rare glial cell-derived neurotrophic factor (GDNF) gene variant. We also demonstrated that cultivating GDNF-silenced human kidney-2 (HK-2) cells in osteogenic conditions for 15 days triggered Ca2PO4 deposits. Given the reportedly close relationship between cell death and pathological calcification, aim of the present study was to investigate whether apoptosis is involved in the calcification of GDNF-silenced HK-2 cells under osteogenic conditions. Silenced and control cells were cultured in standard and osteogenic medium for 1, 5, and 15 days, and any Ca2PO4 deposition was identified by means of von Kossa staining and environmental SEM (ESEM) analyses. Based on the results of annexin V and propidium iodide (PI) analysis, and terminal deoxynucleotidyl transferase dUTP-biotin nick end labeling (TUNEL) assay, the silenced cells in the osteogenic medium showed a significant increase in the percentage of cells in the late phase of apoptosis and an increased Ca2PO4 deposition at 15 days. The results of quantitative real-time PCR (qRT-PCR) of BAX and BCL2, and in-cell Western analysis of caspases indicated that the cell death process was independent of caspase-3, -6, -7, and -9 activation, however. Using this model, we provide evidence of caspase-independent cell death triggering the calcification process in GDNF-silenced HK-2 cells.


Asunto(s)
Fosfatos de Calcio/metabolismo , Muerte Celular/genética , Factor Neurotrófico Derivado de la Línea Celular Glial/genética , Nefrocalcinosis/genética , Apoptosis/genética , Caspasas/genética , Línea Celular , Células Epiteliales/metabolismo , Células Epiteliales/patología , Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Humanos , Etiquetado Corte-Fin in Situ , Nefrocalcinosis/metabolismo , Nefrocalcinosis/patología
5.
J Investig Med ; 51(4): 227-32, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12929739

RESUMEN

BACKGROUND: Hyperbaric oxygen (HBO) therapy is widely used to treat problem wounds associated with pathologic conditions compromising blood supply and tissue oxygenation because increased tissue oxygen levels enhance collagen synthesis, cell proliferation, and angiogenesis. However, little is known about the dose of hyperoxia needed to achieve optimal therapeutic effects. Moreover, HBO, by enhancing the production of reactive oxygen species (ROS), may also exert cytotoxic effects. In vitro models are simplified systems that may aid the development of treatment protocols with HBO. Hence, we have investigated the effects of HBO on the growth and ROS production of the 3T3/J2 fibroblast cell line in relation to the pressure and the duration of exposure. METHODS: 3T3/J2 fibroblasts were plated (5 x 10(3) cells/cm2) on six-well microtiter plates in phosphate buffered saline (PBS), put in a compression chamber, and exposed to 100% oxygen at a pressure of 1.0 or 2.5 atmosphere absolute (ATA) for 15, 30, 60, or 120 minutes. Then the cells were incubated in Dulbecco's modified minimum essential medium (DMEM) for 24, 48, or 72 hours, and at the end of the post-HBO incubation period, their number was determined. In other experiments, cells were detached just after HBO exposure, seeded on 60 mm Petri dishes, and cultured for 10 days in DMEM, and the colony forming units were counted. The effects of HBO exposure (2.5 ATA) on the apoptotic rate of cultured cells were investigated by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and enzyme-linked immunosorbent assays. To measure ROS production, 60 minutes before HBO exposure, 2',7'-dichlorofluorescin (DCF) diacetate (200 nmol/mL) was added to PBS, and after HBO exposure (2.5 ATA), cells were lysated, and fluorescence-emission intensity was measured and converted to micromol DCF/microg protein. RESULTS: At 1.0 ATA, all HBO exposures increased the proliferation rate of cultured fibroblasts and their clonal growth efficiency. At 2.5 ATA, 15-minute exposure to HBO was ineffective, whereas 30- and 60-minute exposures raised the proliferation rate and clonal growth efficiency. Conversely, a 120-minute exposure significantly decreased these parameters compared with control cultures. The exposure of cells to HBO at 2.5 ATA for 120 minutes raised the apoptotic rate of cultured fibroblasts, whereas shorter exposure times were ineffective. All exposure periods to HBO at 2.5 ATA enhanced ROS production from cultured fibroblasts. CONCLUSIONS: Collectively, our findings allow us to conclude that (1) all of the exposure periods to HBO at 1.0 ATA or 30- and 60-minute periods at 2.5 ATA enhance cell growth, (2) 120-minute exposure to HBO at 2.5 ATA exerts a marked proapoptotic effect, and (3) no evident relationships occur between the effects of HBO on cell growth and ROS production.


Asunto(s)
Apoptosis/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Oxigenoterapia Hiperbárica , Oxígeno/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Células 3T3 , Animales , División Celular/efectos de los fármacos , Células Clonales/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/patología , Etiquetado Corte-Fin in Situ , Ratones
6.
ChemSusChem ; 5(9): 1758-66, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22807005

RESUMEN

Two types of new nanocomposite proton-exchange membranes, consisting of functionalized and pristine nanoparticles of silica and silicone rubber (SR) embedded in a polytetrafluoroethylene (PTFE) matrix, were prepared. The membrane precursor was obtained from a mechanical rolling process, and the SiO2 nanoparticles were functionalized by soaking the membranes in a solution of 2-(4-chlorosulfonylphenyl)ethyl trichlorosilane (CSPhEtCS). The membranes exhibit a highly compact morphology and a lack of fibrous PTFE. At 125 °C, the membrane containing the functionalized nanoparticles has an elastic modulus (2.2 MPa) that is higher than that of pristine Nafion (1.28 MPa) and a conductivity of 3.6×10⁻³  S cm⁻¹ despite a low proton-exchange capacity (0.11 meq g⁻¹). The good thermal and mechanical stability and conductivity at T>100 °C make these membranes a promising low-cost material for application in proton-exchange membrane fuel cells operating at temperatures higher than 100 °C.


Asunto(s)
Membranas Artificiales , Nanocompuestos/química , Politetrafluoroetileno/química , Protones , Dióxido de Silicio/química , Fenómenos Mecánicos , Porosidad , Elastómeros de Silicona/química , Temperatura , Agua/química
7.
Hum Pathol ; 43(7): 1028-36, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22079355

RESUMEN

Children with sickle cell anemia may undergo acute splenic sequestration. Splenectomy is performed in an attempt to reduce further events. Histologic studies of spleens have revealed the presence of granuloma-like nodules, known as Gamna-Gandy bodies with amorphous inclusions; however, their significance is unknown. The medical case records and histologic samples of consecutive children with sickle cell anemia treated with splenectomy between 2001 and 2007 at Our Lady's Children's Hospital, Dublin, were reviewed. Seventeen patients were identified. Gamna-Gandy bodies were studied by scanning electron microscopy and x-ray fluorescence spectroscopy. Gamna-Gandy bodies were identified in 7 (41%) patients, and amorphous inclusions were always seen. Patient age correlated significantly with Gamna-Gandy bodies (P = .002). Scanning electron microscopic analysis demonstrated the crystalline nature of Gamna-Gandy bodies and the chemical composition (C 47.1%; O(2) 29.7%; P 9.0%; K(+) 0.4%; Ca(2+) 6.4%; Fe(2+) 7.4%), whereas x-ray diffraction studied the structure (CaPO(4) ∙ FeOH). A crystal-formation gradient was observed, increasing from the red pulp to the white pulp. Our study shows that Gamna-Gandy bodies contain crystals and that their formation is age dependent. We also demonstrated the crystal structure and chemical composition and the relationship between Gamna-Gandy bodies and chest crises presplenectomy or postsplenectomy.


Asunto(s)
Anemia de Células Falciformes/patología , Bazo/patología , Enfermedades del Bazo/patología , Adolescente , Anemia de Células Falciformes/cirugía , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Bazo/cirugía , Esplenectomía , Enfermedades del Bazo/cirugía , Resultado del Tratamiento
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