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1.
AJNR Am J Neuroradiol ; 38(11): 2119-2125, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28882863

RESUMEN

BACKGROUND AND PURPOSE: Anterior communicating artery aneurysm rupture and treatment is associated with high rates of dependency, which are more severe after clipping compared with coiling. To determine whether ischemic injury might account for these differences, we characterized cerebral infarction burden, infarction patterns, and patient outcomes after surgical or endovascular treatment of ruptured anterior communicating artery aneurysms. MATERIALS AND METHODS: We performed a retrospective cohort study of consecutive patients with ruptured anterior communicating artery aneurysms. Patient data and neuroimaging studies were reviewed. A propensity score for outcome measures was calculated to account for the nonrandom assignment to treatment. Primary outcome was the frequency of frontal lobe and striatum ischemic injury. Secondary outcomes were patient mortality and clinical outcome at discharge and at 3 months. RESULTS: Coiled patients were older (median, 55 versus 50 years; P = .03), presented with a worse clinical status (60% with Hunt and Hess Score >2 versus 34% in clipped patients; P = .02), had a higher modified Fisher grade (P = .01), and were more likely to present with intraventricular hemorrhage (78% versus 56%; P = .03). Ischemic frontal lobe infarction (OR, 2.9; 95% CI, 1.1-8.4; P = .03) and recurrent artery of Heubner infarction (OR, 20.9; 95% CI, 3.5-403.7; P < .001) were more common in clipped patients. Clipped patients were more likely to be functionally dependent at discharge (OR, 3.2; P = .05) compared with coiled patients. Mortality and clinical outcome at 3 months were similar between coiled and clipped patients. CONCLUSIONS: Frontal lobe and recurrent artery of Heubner infarctions are more common after surgical clipping of ruptured anterior communicating artery aneurysms, and are associated with poorer clinical outcomes at discharge.


Asunto(s)
Aneurisma Roto/cirugía , Infarto Cerebral/etiología , Embolización Terapéutica/efectos adversos , Embolización Terapéutica/instrumentación , Aneurisma Intracraneal/cirugía , Adulto , Anciano , Aneurisma Roto/complicaciones , Infarto Cerebral/epidemiología , Estudios de Cohortes , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Femenino , Humanos , Aneurisma Intracraneal/complicaciones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Instrumentos Quirúrgicos , Resultado del Tratamiento
2.
Anim Reprod Sci ; 152: 137-53, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25497423

RESUMEN

White rhinoceros ejaculates (n=9) collected by electroejaculation from four males were shipped (10°C, 12h) to develop procedures for the production of chilled and frozen-thawed sex-sorted spermatozoa of adequate quality for artificial insemination (AI). Of all electroejaculate fractions, 39.7% (31/78) exhibited high quality post-collection (≥70% total motility and membrane integrity) and of those, 54.8% (17/31) presented reduced in vitro quality after transport and were retrospectively determined to exhibit urine-contamination (≥21.0µg creatinine/ml). Of fractions analyzed for creatinine concentration, 69% (44/64) were classified as urine-contaminated. For high quality non-contaminated fractions, in vitro parameters (motility, velocity, membrane, acrosome and DNA integrity) of chilled non-sorted and sorted spermatozoa were well-maintained at 5°C up to 54h post-collection, whereby >70% of post-transport (non-sorted) or post-sort (sorted) values were retained. By 54h post-collection, some motility parameters were higher (P<0.05) for non-sorted spermatozoa (total motility, rapid velocity, average path velocity) whereas all remaining motion parameters as well as membrane, acrosome and DNA integrity were similar between sperm types. In comparison with a straw method, directional freezing resulted in enhanced (P<0.05) motility and velocity of non-sorted and sorted spermatozoa, with comparable overall post-thaw quality between sperm types. High purity enrichment of X-bearing (89±6%) or Y-bearing (86±3%) spermatozoa was achieved using moderate sorting rates (2540±498X-spermatozoa/s; 1800±557Y-spermatozoa/s). Collective in vitro characteristics of sorted-chilled or sorted-frozen-thawed spermatozoa derived from high quality electroejaculates indicate acceptable fertility potential for use in AI.


Asunto(s)
Variación Genética , Perisodáctilos/genética , Perisodáctilos/fisiología , Preservación de Semen/veterinaria , Preselección del Sexo/veterinaria , Razón de Masculinidad , Animales , Femenino , Masculino
3.
Theriogenology ; 74(9): 1701-6, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20615535

RESUMEN

The objective was to determine if seminal alkaline phosphatase (ALP) can serve as an indicator of true ejaculation in the rhinoceros. Concentrations of ALP activity were determined in seminal fractions collected from African black rhinos (Diceros bicornis), an African white rhino (Ceratotherium simum), and an Indian rhino (Rhinoceros unicornis) during electroejaculation. In addition, seminal fractions collected during penile massage of a Sumatran rhino (Dicerorhinus sumatrensis) were assessed. Correlations between ALP activity and sperm concentration, fraction pH, and fraction osmolality were evaluated in the Indian rhino and black rhino. Concentrations of ALP activity in rhino ejaculate fractions ranged from < 5 to 11,780 U/L and were positively correlated (P < 0.05) with sperm concentration for both Indian rhino (r = 0.995) and black rhino (r = 0.697), but did not exhibit a strong correlation with either pH or osmolality (P > 0.05). Data were insufficient for establishing meaningful correlation coefficients in the Sumatran rhino and white rhino, but preliminary results were in accordance with findings in the Indian rhino and black rhino. We concluded that ALP was present in rhinoceros semen, likely originated from the epididymides and/or testes, and could serve as a useful tool for assessing the production of ejaculatory versus pre-ejaculatory fluid in the rhinoceros.


Asunto(s)
Fosfatasa Alcalina/análisis , Eyaculación , Perisodáctilos/metabolismo , Semen/enzimología , Animales , Concentración de Iones de Hidrógeno , Masculino , Concentración Osmolar , Recuento de Espermatozoides/veterinaria
4.
J Dent Res ; 85(10): 894-9, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16998127

RESUMEN

Amelogenin RNA transcripts undergo extensive alternative splicing, and MMP-20 processes the isoforms following their secretion. Since amelogenins have been ascribed cell-signaling activities, we asked if a lack of proteolytic processing by MMP-20 affects amelogenin signaling and consequently alters amelogenin splice site selection. RT-PCR analyses of amelogenin mRNA between control and Mmp20(-/-)mice revealed no differences in the splicing pattern. We characterized 3 previously unidentified amelogenin alternatively spliced transcripts and demonstrated that exon-8-encoded amelogenin isoforms are processed by MMP-20. Transcripts with exon 8 were expressed approximately five-fold less than those with exon 7. Analyses of the mouse and rat amelogenin gene structures confirmed that exon 8 arose in a duplication of exons 4 through 5, with translocation of the copy downstream of exon 7. No downstream genomic sequences homologous to exons 4-5 were present in the bovine or human amelogenin genes, suggesting that this translocation occurred only in rodents.


Asunto(s)
Empalme Alternativo/fisiología , Amelogenina/metabolismo , Regulación del Desarrollo de la Expresión Génica/fisiología , Metaloproteinasa 20 de la Matriz/metabolismo , ARN Mensajero/metabolismo , Empalme Alternativo/genética , Amelogenina/genética , Animales , Secuencia de Bases , Esmalte Dental/enzimología , Esmalte Dental/metabolismo , Exones/fisiología , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Metaloproteinasa 20 de la Matriz/genética , Ratones , Ratones Noqueados , Diente Molar/enzimología , Diente Molar/metabolismo , Datos de Secuencia Molecular , Isoformas de Proteínas , Transducción de Señal/genética
5.
Toxicol Lett ; 134(1-3): 301-4, 2002 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-12191892

RESUMEN

Biological monitoring of occupational exposure to benzene has been conducted in the petroleum, steel and chemical industries. The urinary benzene-specific biomarker, S-phenylmercapturic acid (PMA), was quantified in post-shift samples using a sensitive enzyme-linked immunosorbent assay (ELISA) and expressed as a function of urinary creatinine concentration. The assay, based on a PMA-specific antiserum, is sufficiently sensitive to measure PMA levels in non-occupationally exposed control subjects. The assay delivers batch results in a timely manner which may be as short as 3 h. Samples were analysed from groups of workers engaged in coke oven combustion processes, petroleum refining and decontamination of a benzene land spill. The construction of a database of results provides an index of benzene uptake as a consequence of the respective work processes and tasks and readily enables benchmarking exercises aimed at comparing degrees of exposure across segments of industry.


Asunto(s)
Acetilcisteína/análogos & derivados , Benceno/farmacocinética , Industria Química , Bases de Datos Factuales , Monitoreo del Ambiente/métodos , Exposición Profesional/análisis , Acetilcisteína/orina , Biomarcadores/orina , Ensayo de Inmunoadsorción Enzimática , Humanos , Petróleo , Acero
6.
Biomarkers ; 7(2): 103-12, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12101630

RESUMEN

An immunoassay that quantifies urinary S-phenylmercapturic acid (PMA), a benzenespecific biomarker, has been developed and its potential usefulness as a screening tool for monitoring occupational exposure to benzene has been demonstrated. Analytical reliability has been confirmed by correlation of results with gas chromatography-mass spectrometry (GC/MS) data (R = 0.92). The assay has been configured as a competitive enzyme-linked immunosorbent assay (ELISA) to facilitate rapid throughput of samples. The ELISA has a working range of 40-1200 nmoll-1 urinary PMA and appears to be unaffected by the presence of structurally related urinary metabolites. Background levels of 0-1.9 mumol PMA/mol creatinine (mean 0.9 mumol mol-1, n = 32) were measured in nonsmoking control subjects. Recent exposures to benzene (8 h time-weighted averages-TWA), during diverse industrial processes, over the range 0-4.8 ppm were identified by application of the assay in biological monitoring programmes.


Asunto(s)
Acetilcisteína/análogos & derivados , Acetilcisteína/orina , Benceno/metabolismo , Monitoreo del Ambiente/métodos , Exposición Profesional , Biomarcadores , Ensayo de Inmunoadsorción Enzimática , Cromatografía de Gases y Espectrometría de Masas , Humanos
7.
J Zoo Wildl Med ; 32(2): 242-4, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12790428

RESUMEN

Mycobacterium avium subsp. paratuberculosis was cultured from a single fecal sample collected from a 10-yr-old, captive-bred male addax (Addax nasomaculatus). Attempts to confirm infection with additional fecal cultures, serology, semen culture, and tissue biopsy were unsuccessful. There were no gross lesions on necropsy. On histopathology there were neither acid-fast organisms nor microscopic changes suggestive of active or clinical Johne's disease. Mycobacterium avium subsp. paratuberculosis was isolated from four organ tissues: ileum, jejunum, colon, and mesenteric lymph node.


Asunto(s)
Antílopes , Paratuberculosis/diagnóstico , Animales , Animales de Zoológico , Eutanasia Animal , Heces/microbiología , Masculino , Mycobacterium avium subsp. paratuberculosis/aislamiento & purificación , Paratuberculosis/patología , Semen/microbiología
8.
J Zoo Wildl Med ; 29(2): 221-4, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9732041

RESUMEN

An adult white-handed gibbon (Hylobates lar) at a zoo in eastern Kansas was euthanized after developing a head tremor, generalized motor incoordination, and partial paresis of the right arm that persisted over 2 yr. Magnetic resonance imaging early in the course of the disease demonstrated a localized left frontal lobe cerebritis. Larvae morphologically consistent with a Baylisascaris species were seen in tissue sections of the cerebrum and cerebellum. Epizootiologic investigation, which included qualitative fecal flotations, evaluation of soil samples for nematode eggs, and necropsy examination of livetrapped raccoons (Procyon lotor), indicated that Baylisascaris procyonis was most likely to have caused the cerebrospinal nematodiasis in this gibbon.


Asunto(s)
Infecciones por Ascaridida/veterinaria , Ascaridoidea/aislamiento & purificación , Enfermedades del Sistema Nervioso Central/veterinaria , Hylobates/parasitología , Enfermedades de los Primates/parasitología , Animales , Animales de Zoológico , Infecciones por Ascaridida/parasitología , Infecciones por Ascaridida/patología , Encéfalo/parasitología , Encéfalo/patología , Enfermedades del Sistema Nervioso Central/parasitología , Enfermedades del Sistema Nervioso Central/patología , Cerebelo/parasitología , Cerebelo/patología , Femenino , Imagen por Resonancia Magnética/veterinaria , Examen Neurológico/veterinaria , Enfermedades de los Primates/patología , Mapaches
9.
J Immunoassay ; 18(3): 235-46, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9257263

RESUMEN

A competitive monoclonal antibody-based immunoassay which quantifies a hydrophobic hapten (Rx) in water immiscible solvents, obviating the need of a pre-extraction step, has been developed. Approximately linear dose response profiles of analyte, over the range 1-20 ugml-1 in the hydrophobic solvents, hexane, toluene and xylene were obtained. UV spectrophotometric analyses of Rx dosed hexane confirm the phenomenon of antibody-mediated transfer of analyte from the organic to the aqueous milieu. Preliminary data on the effect of water immiscible solvents on the immunoreactivity of a monoclonal antibody in free solution are presented. The potential industrial applications of water immiscible solvent based immunoassays are discussed.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Solventes , Agua , Anticuerpos Monoclonales/química , Relación Dosis-Respuesta Inmunológica , Haptenos/inmunología , Humanos , Albúmina Sérica/química , Solubilidad , Rayos Ultravioleta
10.
Cell Motil Cytoskeleton ; 23(4): 265-78, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1477889

RESUMEN

Previous studies suggest that alterations in the microtubule (MT)-tubulin equilibrium during G0/G1 affect mitogenesis. To determine the effect of growth factors on the MT-tubulin equilibrium, we developed a radioactive monoclonal antibody binding assay (Ball et al.: J. Cell. Biol. 103:1033-1041, 1986). With this assay, 3H-Ab 1-1.1 binding to cytoskeletons in confluent populations of cultured cells is proportional to the number of tubulin subunits polymerized into MTs. We now show that purified alpha-thrombin increases 3H-Ab 1-1.1 binding to cytoskeletons of serum-arrested mouse embryo (ME) fibroblasts from 1.5- to 3-fold. This stimulation is dose-dependent and correlates with concentrations of thrombin required for initiation of DNA synthesis. Other mitogenic factors, epidermal growth factor (EGF) and phorbol 12-myristate 13-acetate (PMA), also stimulate MT polymerization. Addition of colchicine (0.3 microM) eight hours after growth factor addition, blocks stimulation of 3H-thymidine incorporation by thrombin, EGF, or PMA, suggesting that tubulin polymerization or subsequent events triggered by MT polymerization are required for cells to enter a proliferative cycle. Consistent with models for autoregulation of tubulin synthesis, thrombin, EGF, and PMA all increase tubulin synthesis 9 to 15 hr after growth factor addition, raising the possibility that the decrease in free tubulin and subsequent stimulation of tubulin synthesis is linked to progression of cells into a proliferative cycle. Colchicine addition to these cells also stimulates DNA synthesis, but colchicine-stimulated cells enter S phase 6 to 8 hr later than those stimulated by growth factors. This delayed stimulation may be related to the time required for degradation of tubulin-colchicine complexes below a critical level. These data suggest that regulation of cell proliferation may be linked to increased MT polymerization and the resulting decrease in free tubulin pools.


Asunto(s)
Factor de Crecimiento Epidérmico/farmacología , Acetato de Tetradecanoilforbol/farmacología , Trombina/farmacología , Tubulina (Proteína)/metabolismo , Animales , Sitios de Unión de Anticuerpos/efectos de los fármacos , Células Cultivadas/metabolismo , Fibroblastos/metabolismo , Ratones , Microtúbulos/metabolismo , Mitosis/efectos de los fármacos
11.
Exp Cell Res ; 191(1): 37-44, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1977604

RESUMEN

The microtubule (MT)-stabilizing drug, taxol, inhibited human cytomegalovirus (CMV)-initiated cell DNA synthesis by up to 100% in serum-arrested mouse embryo (ME) fibroblasts that were abortively infected by CMV. Taxol concentrations known to increase MT polymerization and to stabilize existing MTs (10 to 20 micrograms/ml) blocked CMV-stimulated cell DNA synthesis, while taxol concentrations of 2.5 micrograms/ml, or less, did not. Taxol maximally inhibited CMV initiation of cell DNA synthesis when added 3 h after virus infection and inhibited this initiation by greater than 50% when added up to 12 h after CMV infection. Control experiments suggest that taxol specifically inhibited CMV-stimulated cell DNA synthesis. Pretreatment of CMV stock with taxol did not reduce the stimulatory effect of CMV on cell DNA synthesis and taxol had no detectable effect on CMV-specific early protein synthesis. Moreover, taxol did not appear to alter thymidine pool sizes, affect cell viability, or compromise the DNA synthetic machinery in CMV-infected cells. Since taxol increases tubulin polymerization and inhibits MT disassembly, these results suggest that dynamic changes in MTs or in the pool of free tubulin subunits are necessary for CMV to stimulate cell entry into a proliferative cycle.


Asunto(s)
Alcaloides/farmacología , Citomegalovirus/efectos de los fármacos , ADN/efectos de los fármacos , Animales , División Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Transformación Celular Viral/efectos de los fármacos , Transformación Celular Viral/genética , Células Cultivadas , Citomegalovirus/genética , ADN/biosíntesis , ADN Viral/biosíntesis , Embrión de Mamíferos , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Ratones , Microtúbulos/metabolismo , Paclitaxel , Transducción de Señal/efectos de los fármacos , Transfección/genética , Tubulina (Proteína)/metabolismo
12.
J Biol Chem ; 265(22): 12836-45, 1990 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-1695898

RESUMEN

Epidermal growth factor (EGF) treatment of A-431 cells potentiates up to 5-fold the intracellular cyclic AMP (cAMP) accumulation induced by isoproterenol, cholera toxin, forskolin, or 3-isobutyl-1-methylxanthine (IBMX). EGF potentiates cAMP accumulation in several epithelial cell lines which overexpress the EGF receptor including A-431 cells, HSC-1 cells, and MDA-468 cells, and in the A-431-29S clone which expresses a normal complement of EGF receptors. Although EGF potentiates cAMP accumulation, EGF by itself does not measurably alter the basal level of cAMP. EGF rapidly enhances cAMP accumulation (within 1 to 3 min) in A-431 cells treated with these cAMP-elevating agents. EGF potentiation of cAMP accumulation does not reflect enhancement of beta-adrenergic receptor activation and is not a consequence of intracellular cAMP elevation or the concomitant activation of cAMP-dependent protein kinase. Since EGF potentiates accumulation of both intracellular and extracellular cAMP in isoproterenol-treated A-431 cells, EGF does not potentiate intracellular cAMP accumulation by inhibition of cAMP export. EGF potentiation of cAMP accumulation is pertussis toxin-insensitive and does not result from EGF inhibition of cAMP degradation in A-431 cells. These results demonstrate that EGF transmembrane signaling includes an interaction with a component of the adenylate cyclase system and that this interaction stimulates cAMP synthesis resulting in enhancement of cAMP accumulation.


Asunto(s)
AMP Cíclico/metabolismo , Factor de Crecimiento Epidérmico/farmacología , Células Tumorales Cultivadas/metabolismo , 1-Metil-3-Isobutilxantina/farmacología , Bucladesina/farmacología , Carcinoma de Células Escamosas , Línea Celular , Toxina del Cólera/farmacología , Colforsina/farmacología , Sinergismo Farmacológico , Humanos , Isoproterenol/farmacología , Cinética , Células Tumorales Cultivadas/efectos de los fármacos
13.
J Cell Biol ; 103(3): 1033-41, 1986 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3528166

RESUMEN

To detect changes in the extent of tubulin polymerization in cultured cells, we have developed a radioactive antibody binding assay that can be used to quantitate total cytoskeletal tubulin or specific antigenic subsets of polymerized tubulin. Fibroblastic cells, grown to confluence in multiwell plates, were permeabilized and extracted with 0.5% Triton X-100 in a microtubule-stabilizing buffer. These extracted cytoskeletons were then fixed and incubated with translationally radiolabeled monoclonal antitubulin antibody (Ab 1-1.1), an IgM antibody specific for the beta subunit of tubulin. Specific binding of Ab 1-1.1 to the cytoskeletons was saturable and of a single apparent affinity. All specific binding was blocked by preincubation of the radiolabeled antibody with excess purified brain tubulin. Specific Ab 1-1.1 binding appeared to represent binding to cytoskeletal tubulin inasmuch as: pretreatment of cells with colchicine decreased Ab 1-1.1 binding in a dose-dependent manner which correlated with the amount of polymerized tubulin visualized in parallel cultures by indirect immunofluorescence, taxol pretreatment alone caused an increase in Ab 1-1.1 binding and prevented in a dose-dependent manner the colchicine-induced decrease in antibody binding, in cells pretreated with colcemid and returned to fresh medium, Ab 1-1.1 binding decreased and recovered in parallel with the depolymerization and regrowth of microtubules in these cells, and comparison of maximal antibody binding per cell between primary mouse embryo, 3T3, and human foreskin fibroblasts correlated with immunofluorescence visualization of microtubules in these cells. Thus, this assay can be used to measure relative changes in the level of polymerized cytoskeletal tubulin. Moreover, by Scatchard-type analysis of the binding data it is possible to estimate the total number of antibody binding sites per cell. Therefore, depending on the stoichiometry of antibody binding, this type of assay may be used for quantitating total cytoskeletal tubulin, specific antigenic subsets of cytoskeletal tubulin, or other cytoskeletal proteins.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Citoesqueleto/análisis , Microtúbulos/análisis , Radioinmunoensayo/métodos , Tubulina (Proteína)/análisis , Animales , Especificidad de Anticuerpos , Células Cultivadas , Citoesqueleto/ultraestructura , Fibroblastos/análisis , Fibroblastos/ultraestructura , Técnica del Anticuerpo Fluorescente , Ratones , Microtúbulos/ultraestructura , Tubulina (Proteína)/inmunología
14.
Am J Phys Med ; 48(3): 116-8, 1969 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-5788465
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