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1.
Opt Lett ; 43(2): 296-299, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-29328264

RESUMEN

We demonstrate an all-fiber supercontinuum source that generates a continuous spectrum from 1.6 µm to >11 µm with 417 mW on-time average power at 33% duty cycle. By utilizing a master oscillator power amplifier pump with three amplification stages and concatenating solid core ZBLAN, arsenic sulfide, and arsenic selenide fibers, we shift 1550 nm light to ∼4.5 µm, ∼6.5 µm, and >11 µm, respectively. With 69 mW past 7.5 µm, this source provides both high power and broad spectral expansion, while outputting a single fundamental mode.

2.
Appl Opt ; 57(10): 2519-2532, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29714236

RESUMEN

We generate a supercontinuum (SC) spectrum ranging from 1.57 µm to 12 µm (20 dB bandwidth) with a soft glass fiber cascade consisting of ZrF4-BaF2-LaF3-AlF3-NaF fiber, As2S3 fiber, and As2Se3 fiber pumped by a nanosecond thulium master oscillator power amplifier system. The highest on-time average power generated is 417 mW at 33% duty cycle. We observe a near-diffraction-limit beam quality across the wavelength range from 3 µm to 12 µm, even though the As2Se3 fiber is multimode below 12 µm. Our study also shows that parameters of the As2Se3 fiber, such as numerical aperture, core size, and core/cladding composition, have significant effects on the long wavelength edge of the generated SC spectrum. Our results suggest that the high numerical aperture of 0.76 and low-loss As2Se3/GeAs2Se5 core/cladding material all contribute to broad SC generation in the long-wave infrared spectral region. Also, among our results, 10 µm core diameter selenide fiber yields the best spectral expansion, while the 12 µm core diameter selenide fiber yields the highest output power.

3.
BJU Int ; 111(1): 159-70, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22672418

RESUMEN

OBJECTIVE: To determine the gene expression profile of pelvic ganglia neurones after bilateral cavernosal nerve resection (BCNR) and subsequent treatment with sildenafil in relation to neurotrophic-related pathways. MATERIALS AND METHODS: Fisher rats aged 5 months were subjected to BCNR or sham operation and treated with or without sildenafil (20 mg/kg body-weight in drinking water) for 7 days. Total RNA isolated from pelvic ganglia was subjected to reverse transcription and then to quantitative reverse transcriptase-polymerase chain reaction (PCR) with the RAT-neurotrophic array. Results were corroborated by real-time PCR and western blotting. Another set of animals were injected with a fluorescent tracer at the base of the penis, 7 days before BCNR or sham operation, and were sacrificed 7 days after surgery. Sections of pelvic ganglia were used for immunohistochemistry with antibodies against neurturin, neuronal nitric oxide synthase, tyrosine hydroxylase and glial cell line-derived neurotrophic factor receptor α2. RESULTS: A down-regulation of the expression of neuronal nitric oxide synthase accompanied by changes in the level of cholinergic neurotrophic factors, such as neurturin and its receptor glial cell line-derived neurotrophic factor receptor α2, artemin, neurotrophin-4 and cilliary neurotrophic factor, was observed 7 days after BCNR in pelvic ganglia neurones. Treatment with sildenafil, starting immediately after surgery, reversed all these changes at a level similar to that in sham-operated animals. CONCLUSIONS: Sildenafil treatment promotes changes in the neurotrophic phenotype, leading to a regenerative state of pelvic ganglia neurones. The present study provides a justification for the use of phosphodiesterase 5 inhibitors as a neuroprotective agent after BCNR.


Asunto(s)
Ganglios Autónomos/efectos de los fármacos , Receptores del Factor Neurotrófico Derivado de la Línea Celular Glial/genética , Fármacos Neuroprotectores/farmacología , Pene/inervación , Inhibidores de Fosfodiesterasa 5/farmacología , Piperazinas/farmacología , Sulfonas/farmacología , Animales , Ganglios Autónomos/metabolismo , Expresión Génica/efectos de los fármacos , Receptores del Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Masculino , Neuronas/metabolismo , Neurturina/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Tratamientos Conservadores del Órgano/métodos , Pelvis/inervación , Pene/efectos de los fármacos , Pene/cirugía , Purinas/farmacología , Ratas , Ratas Endogámicas F344 , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Citrato de Sildenafil
4.
Environ Sci Pollut Res Int ; 29(17): 25869-25880, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34850349

RESUMEN

The textile industry is an important potential source of environmental pollution due to the use of chemical products. Dyes, hydrolyzed dyes, and surfactants, among others, are chemical compounds present in wastewater of textile plant. Moreover, the anionic surfactants have toxic effects for various aquatic organisms even in low concentrations. The methodologies investigated to quantify surfactants, in general, consume a lot of analysis time and frequently use toxic or environmentally objectionable reagents. For these reasons, the objective of this work was to develop a quick and simple method to quantify surfactants without the use of expensive reagents and equipment, avoiding extraction and preconcentration stages. The proposed method is based on fluorescent spectroscopy measurements for the acquisition of second-order data in excitation-emission matrices and multivariate calibration techniques applied to the data. The unfolded partial least squares combined to residual bilinearization (U-PLS/RBL) algorithm was better than parallel factor analysis (PARAFAC). U-PLS/RBL accurately quantified alkylnonylphenolethoxylated (APEO), dodecylbenzenesulfonic acid (ADBS), and 2-phenoxy-ethoxylated fatty alcohol (AGFE) surfactants. The chemometric model obtained good analytical figures of merit: REP% between 5 and 13 and LOQ between 0.45 and 2.77 µg mL-1. This methodology had no significant difference compared with results obtained by a HPLC-FD reference technique, in addition with a considerable reduction in analysis time, reagent consumption, and therefore lower cost. For environmental applications, APEO, ADBS, and AGFE were quantify in textile wastewater treatment and in the receiving water body. The concentrations varied from 8.73 to 73.94 µg mL-1 in the textile wastewater and were not detected in the receiving water body.


Asunto(s)
Tensoactivos , Aguas Residuales , Algoritmos , Calibración , Colorantes , Análisis de los Mínimos Cuadrados , Espectrometría de Fluorescencia/métodos , Textiles , Agua
5.
J Histochem Cytochem ; 34(7): 913-22, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3519755

RESUMEN

Glutamate dehydrogenase (GDH) was localized in rat liver by indirect electron microscopic immunogold, using different sizes of gold particles and monoclonal and polyclonal antibodies. Using the protein A-gold technique in double immunocytochemical experiments, both antibodies, at their optimal dilutions, gave similar results. A novel assessment of the distribution of GDH was made by measurements of the number of gold particles per square micrometer of cross-sectional images of individual mitochondria. The data indicate intracellular homogeneity among mitochondria in individual parenchymal cells. The enzyme is almost absent in non-parenchymal cells. Finally, GDH was found mainly in association with the mitochondrial inner membrane.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Anticuerpos/inmunología , Glutamato Deshidrogenasa/análisis , Oro , Técnicas Inmunológicas , Mitocondrias Hepáticas/enzimología , Animales , Compartimento Celular , Glutamato Deshidrogenasa/inmunología , Histocitoquímica , Membranas Intracelulares/inmunología , Masculino , Mitocondrias Hepáticas/ultraestructura , Ratas , Ratas Endogámicas , Proteína Estafilocócica A
6.
J Histochem Cytochem ; 35(8): 897-907, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3598170

RESUMEN

Carbamoyl phosphate synthetase I (CPS-I) is the most abundant protein of rat liver mitochondria. Biochemical measurements in liver homogenates have shown that the liver from rats fed a high-protein diet contains more CPS-I per gram tissue protein than controls. However, there is no information on changes in the intact tissue at the cellular and mitochondrial level. Therefore, monoclonal antibodies to beef liver CPS-I were produced by the hybridoma technique. Four clones, C-241/1A, B, C, and D secreted immunogammaglobulin (IgG) IgG1. Using C-241/C, we measured by electron microscopy immunogold procedures the labeling of CPS-I in mitochondria from liver of rats fed high protein (casein, 50 and 80% of total food intake) diets. CPS-I (expressed as gold particles/micron2 of mitochondrial cross-sectional area) was greater than in mitochondria from control rats (20% casein diet), whether the rats were fed for 1, 6, or 14 months on the high-protein diets. The immunocytochemical measurements shown here demonstrate that the increase in the level of CPS-I in high-protein diets is a reflection of both the larger number of CPS-I molecules per mitochondrial area and the larger proportion of the total hepatocyte volume occupied by mitochondria. Similar measurements were carried out with glutamate dehydrogenase (GDH) using previously characterized monoclonal antibodies. No differences in GDH labeling were found with high-protein diets. Interestingly, when mitochondria from hepatocytes of rats fed a high-protein diet were divided into two subpopulations on the basis of mitochondrial cross-sectional size (i.e., greater or less than 0.7 micron2), the large mitochondria had 1.2 times more CPS-I and 0.8 times less GDH than the small mitochondria nearby.


Asunto(s)
Anticuerpos Monoclonales , Carbamoil-Fosfato Sintasa (Amoniaco)/metabolismo , Proteínas en la Dieta/metabolismo , Ligasas/metabolismo , Mitocondrias Hepáticas/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Glutamato Deshidrogenasa/metabolismo , Oro , Microscopía Electrónica , Ratas
7.
J Histochem Cytochem ; 36(11): 1433-40, 1988 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3171166

RESUMEN

Glutamate dehydrogenase and carbamoyl phosphate synthase-I were localized in rat liver by immunogold procedures, using monoclonal and polyclonal antibodies. As expected, there was extensive labeling in mitochondria. Label was also found in lysosomal autophagic vacuoles. When autophagy was stimulated by in vivo administration of the anti-microtubular agent vinblastine we found that: (a) carbamoyl phosphate synthase-I and glutamate dehydrogenase could be found in mitochondria within autophagic vacuoles; (b) the carbamoyl phosphate synthase-I and glutamate dehydrogenase content of the mitochondria sequestered into autophagic vacuoles is the same as that of the nearby "free" mitochondria; and (c) in the whole liver, autophagic vacuoles contain c. 1.5 times more glutamate dehydrogenase than carbamoyl phosphate synthase-I, in contrast to mitochondria which have c. three times more carbamoyl phosphate synthase-I than glutamate dehydrogenase. The latter finding could explain, at least partially, the difference in half-lives of these enzymes.


Asunto(s)
Autofagia , Carbamoil-Fosfato Sintasa (Amoniaco)/metabolismo , Glutamato Deshidrogenasa/metabolismo , Inmunohistoquímica , Mitocondrias Hepáticas/enzimología , Fagocitosis , Animales , Autofagia/efectos de los fármacos , Masculino , Mitocondrias Hepáticas/ultraestructura , Fagocitosis/efectos de los fármacos , Ratas , Ratas Endogámicas , Vacuolas/enzimología , Vacuolas/ultraestructura , Vinblastina/farmacología
8.
J Histochem Cytochem ; 38(3): 371-6, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2303702

RESUMEN

Carbamoyl phosphate synthetase I, the most abundant protein of rat liver mitochondria, plays a key role in synthesis of urea. Because aging affects some liver functions, and because there is no information on the levels of carbamoyl phosphate synthetase I during aging, we assayed the activity of this enzyme and determined immunologically the level of carbamoyl phosphate synthetase I in liver homogenates from young (4 months) and old (18 or 26 months) rats. In addition, we used electron microscopic immunogold procedures to locate and measure the amount of the enzyme in the mitochondrial matrix. There is no significant change in enzyme activity or enzyme protein content with age, although there is a higher concentration of the enzyme in the mitochondria (c. 1.5 times greater) from old rats, which is compensated by a decrease in the fractional volume of the mitochondrial compartment during aging.


Asunto(s)
Envejecimiento/metabolismo , Carbamoil-Fosfato Sintasa (Amoniaco)/análisis , Mitocondrias Hepáticas/enzimología , Factores de Edad , Animales , Anticuerpos Monoclonales , Carbamoil-Fosfato Sintasa (Amoniaco)/inmunología , Inmunoensayo , Immunoblotting , Inmunohistoquímica , Masculino , Mitocondrias Hepáticas/ultraestructura , Ratas , Ratas Endogámicas , Conservación de Tejido
9.
J Histochem Cytochem ; 36(1): 41-7, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3335769

RESUMEN

In adult rat liver, glutamate dehydrogenase is present in high concentrations around the terminal portal (zone 1) and hepatic (zone 3) veins, whereas its concentration is low in the intermediate zone. Although the size and staining intensity of the periportal glutamate dehydrogenase-positive compartment are less than those of the pericentral compartment, it can expand under appropriate endocrine conditions, leading to a homogeneous distribution. At birth, glutamate dehydrogenase is also homogeneously distributed. Glutamate dehydrogenase disappears from the periportal compartment during the first postnatal week and reappears in that compartment after weaning. These observations indicate an independent regulation of glutamate dehydrogenase levels in the periportal and pericentral zone. The size of the periportal glutamate dehydrogenase-containing zone is appreciably smaller than that of carbamoylphosphate synthetase, whereas the pericentral glutamate dehydrogenase-containing zone is appreciably larger than that of glutamine synthetase. The heterogeneous distribution of glutamate dehydrogenase suggests the possibility that, under normal conditions, deamination of glutamate prevails in the periportal compartment and amination of glutamate in the pericentral compartment.


Asunto(s)
Envejecimiento/metabolismo , Glutamato Deshidrogenasa/análisis , Hígado/enzimología , Animales , Carbamoil-Fosfato Sintasa (Amoniaco)/análisis , Diabetes Mellitus Experimental/enzimología , Fijadores , Glucocorticoides/farmacología , Glutamato Deshidrogenasa/metabolismo , Venas Hepáticas , Inmunohistoquímica , Hígado/efectos de los fármacos , Hígado/crecimiento & desarrollo , Vena Porta , Ratas , Ratas Endogámicas , Distribución Tisular
10.
Leuk Res ; 8(3): 491-500, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6431200

RESUMEN

Mononuclear cells from a bone marrow infiltrated by plasmacytoma cells were examined by electron microscopy. An analysis was performed according to different cytoarchitectural forms of the endoplasmic reticulum (ER). Six types of plasma cells could be distinguished. The bone marrow cells were treated with an anti-idiotype antiserum from a guinea pig prepared against the patient's monoclonal serum protein and with a FITC conjugated anti-guinea pig antiserum from the rabbit as second layer. Then the cells were passed through an affinity gel column with anti-FITC antibodies. The original preparation and the cells separated on the affinity gel were analysed by electron microscopy. It was found that an ultrastructurally distinct type of plasma cell was enriched 3.5-fold over the original sample by the separation procedure.


Asunto(s)
Anticuerpos Antiidiotipos , Idiotipos de Inmunoglobulinas/inmunología , Plasmacitoma/ultraestructura , Separación Celular , Cromatografía de Afinidad , Retículo Endoplásmico/ultraestructura , Fluoresceína-5-Isotiocianato , Fluoresceínas , Colorantes Fluorescentes , Humanos , Microscopía Electrónica , Plasmacitoma/inmunología , Plasmacitoma/patología , Tiocianatos
11.
Genet Test Mol Biomarkers ; 16(8): 855-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22524166

RESUMEN

BACKGROUND: The C allele of c.-94C>G polymorphism of the delta-sarcoglycan gene was associated as a risk factor for coronary spasm in Japanese patients with hypertrophic cardiomyopathy (HCM). AIM: We evaluated whether the c.-94C>G polymorphism can be a risk factor for HCM in Mexican patients. METHODS: The polymorphism was genotyped and the risk was estimated in 35 HCM patients and 145 healthy unrelated individuals. Data of this polymorphism reported in Mexican Amerindian populations were included. RESULTS: The C allele frequency in HCM patients was higher with an odds ratio (OR) of 2.37, and the risk for the CC genotype increased to 5.0. The analysis with Mexican Amerindian populations showed that the C allele frequency was significantly higher in HCM patients with an OR of 2.96 and for CC genotype the risk increased to 7.60. CONCLUSIONS: The C allele of the c.-94C>G polymorphism is a risk factor for HCM, which is increased by the Amerindian component and can play an important role in the etiology and progression of disease in Mexican patients.


Asunto(s)
Cardiomiopatía Hipertrófica/genética , Predisposición Genética a la Enfermedad , Sarcoglicanos/genética , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , México , Persona de Mediana Edad , Mutación , Factores de Riesgo
12.
Artículo en Inglés | MEDLINE | ID: mdl-43019

RESUMEN

Incorporation of tritiated amino acids and uridine was studied in untreated and actinomycin D treated HeLa cells by high resolution autoradiography. Results showed a non-selective inhibition of protein synthesis by actinomycin, as measured by the decrease in radioactive amino acid uptake. When cells pretreated with actinomycin D were incubated with radioactive amino acids and uridine, amino acid uptake in the nucleolus still occurred, while uridine uptake was almost completely eliminated. These findings suggest that in the absence of ribosomal RNA precursor synthesis, nucleolar protein synthesis continues to some extent, and that this protein is transported to the nucleolus.


Asunto(s)
Dactinomicina/farmacología , Biosíntesis de Proteínas , ARN Ribosómico/biosíntesis , Ribosomas/efectos de los fármacos , Nucléolo Celular/metabolismo , Células HeLa/efectos de los fármacos , Humanos , Ribosomas/metabolismo
13.
Cell Biol Int Rep ; 8(8): 665-74, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6478517

RESUMEN

This paper describes the isolation and characterization of a monoclonal antibody to bovine liver glutamate dehydrogenase (GDH). Monoclonal antibody is mouse immunoglobulin subclass IgG2a and reacts strongly with the antigen in an enzyme-linked immunosorbent assay (ELISA). Its specificity was determined by an antigen binding assay and by Western blotting. Potential uses and possible applications are discussed.


Asunto(s)
Anticuerpos Monoclonales/aislamiento & purificación , Glutamato Deshidrogenasa/inmunología , Animales , Bovinos , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Ratones , Ratones Endogámicos BALB C , Mitocondrias Hepáticas/enzimología , Peso Molecular
14.
J Gen Microbiol ; 130(5): 1193-9, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6236280

RESUMEN

The localization of chitin synthase in the cells of Mucor rouxii was studied by a method which combined permeabilization of the cells with toluene/ethanol and incubation with the radioactive substrate UDP-[3H]GlcNAc followed by high resolution autoradiography. By this technique it was demonstrated that most of the chitin synthesized by these cells was located within the cytoplasm, and only a small amount of the enzyme product appeared at the cell surface. It was concluded that most of the chitin synthase of M. rouxii is located in the cytoplasm of the cells.


Asunto(s)
Quitina Sintasa/análisis , Glucosiltransferasas/análisis , Mucor/enzimología , Autorradiografía , Quitina Sintasa/antagonistas & inhibidores , Citoplasma/enzimología , Citoplasma/ultraestructura , Microscopía Electrónica , Mucor/ultraestructura , Péptido Hidrolasas/farmacología
15.
J Submicrosc Cytol ; 15(3): 607-18, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6876217

RESUMEN

Stereologic ultrastructural methods were applied to several cell types involved in the production of monoclonal antibodies against the mitochondrial enzyme glutamic dehydrogenase (GDH). These cell types included SP2/O murine cells, in vitro cultured hybrid cells producing monoclonal antibodies, and the same hybrid cells maintained as solid and ascites tumors (TH and ATH cells, respectively). The statistical analysis of quantitative data indicates that the fusion between SP2/O cells and spleen lymphocytes does not induce significant changes in the fine structure of the former cells. Moreover, the transfer of hybrid cells from in vitro to in vivo conditions induces their transformation from an immature state to mature plasma cells. The increase in mitochondria and rough endoplasmic reticulum suggests that the ascites tumor provides cells with an environment more suitable for expressing their activity than does the solid tumor.


Asunto(s)
Hibridomas/ultraestructura , Plasmacitoma/ultraestructura , Animales , Anticuerpos Monoclonales/biosíntesis , Fusión Celular , Nucléolo Celular/ultraestructura , Núcleo Celular/ultraestructura , Ratones , Microscopía Electrónica/métodos , Mitocondrias/ultraestructura , Neoplasias Experimentales/ultraestructura
16.
Physiol Chem Phys ; 14(4): 327-33, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-6310654

RESUMEN

Monolayer cultures of 3T3 and WI-38 fibroblasts were pulse labeled with radioactive leucine in the presence of cycloheximide. The rate of protein degradation was measured and compared with that of SV-40 virus transformed cells. The results clearly show that normal and transformed cells have essentially identical rates of degradation of proteins synthesized in the presence of cycloheximide. These findings indicate that the lower rates of protein degradation observed in some transformed cells is not a general rule.


Asunto(s)
Transformación Celular Neoplásica , Cicloheximida/farmacología , Proteínas de Neoplasias/metabolismo , Biosíntesis de Proteínas/efectos de los fármacos , Proteínas/metabolismo , Animales , Células Cultivadas , Cloranfenicol/farmacología , Cinética , Ratones , Ratones Endogámicos BALB C , Virus 40 de los Simios/genética , Fracciones Subcelulares/metabolismo
17.
Cell Tissue Res ; 205(2): 303-9, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-7357575

RESUMEN

Ferritin was trapped in negatively charged liposomes consisting of phosphatidyl choline and phosphatidyl serine in a molar ratio of 9:1. Unilamellar vesicles were prepared by ultrasonic treatment. HeLa cells were incubated with these liposomes for 2h and chased for 0, 2, 14 and 20 h. The migration pathway of ferritin in the cells was followed by quantitative electron microscopy. Ferritin was detected exclusively in cytosol and lysosomes. Evidence is presented that free ferritin in cytosol enters lysosomes.


Asunto(s)
Autofagia , Citosol/metabolismo , Ferritinas/metabolismo , Lisosomas/metabolismo , Fagocitosis , Células HeLa , Humanos , Liposomas , Lisosomas/ultraestructura
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