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1.
J Eur Acad Dermatol Venereol ; 34(12): 2795-2801, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32401355

RESUMEN

BACKGROUND: Vascular targeted photodynamic therapy (PDT) is a novel and promising therapy for the treatment of port-wine stains (PWS). There has been little prior exploration to our knowledge of how the dermatological vascular pattern may predict the response to PDT. OBJECTIVES: To analyse whether the vascular pattern classifications of PWS by dermoscopy can predict the efficacy of PDT. METHODS: This prospective cohort study included 163 patients with a clinical diagnosis of PWS who were treated twice with hemoporfin-mediated photodynamic therapy (HMME-PDT) at two-month intervals and followed up for 6 months. The vascular manifestations of dermoscopy with PWS were independently classified into 8 categories by 3 dermatologists. Images of the lesions were taken using VISIA, and the vascular patterns were imaged by dermoscopy by the same investigator. Images were captured before and after each treatment. The efficacy was evaluated with pre- and post-treatment VISIA images, and correlations between efficacy and vascular patterns were analysed by four dermatologists in a blinded and independent manner, between 10 January 2019 and 11 December 2019. RESULTS: In the dermoscopy images for the whole cohort, dotted and globular vessels (15.3%), short clubbed vessels (18.4%) and curved vessels (12.9%) were highly associated with cure and beneficial treatment effects. Pale halos surrounding brown dots (8.0%) and arborizing vessels (9.8%) were mainly correlated with skin lesion alleviation. Mixed vessels (12.9%), a grey-whitish veil (11.7%) and reticular patterns (11.0%) were mainly associated with no effect. The differences between each subgroup were statistically significant (P = 0.000). CONCLUSIONS: There is a clear correlation between the efficacy of PDT and the dermoscopy pattern in patients with PWS. Dermoscopy may therefore provide very useful clinical information prior to treatment in these cases. In addition, the vascular manifestations of PWS determined by dermoscopy help to predict response to PDT and manage patient expectations.


Asunto(s)
Fotoquimioterapia , Mancha Vino de Oporto , Dermoscopía , Hematoporfirinas , Humanos , Fármacos Fotosensibilizantes/uso terapéutico , Mancha Vino de Oporto/diagnóstico por imagen , Mancha Vino de Oporto/tratamiento farmacológico , Estudios Prospectivos
2.
Artículo en Chino | MEDLINE | ID: mdl-32306638

RESUMEN

Objective: To compare intact dissection and segmented dissection of cochlear surface preparation in adult mice. Methods: From February to March, 2019, Six adult C57BL/6 mice were randomly divided into 2 groups: one group (3 mice) for the intact dissection while the other group (3 mice) for the segmented dissection. Cochlear hair cells were labeled with phalloidin for evaluation of the integrity of the basilar membrane. Results: The basilar membranes can be completely dissected from the cochlea by two approaches. The average dissection time is (16.33±1.86)min with the intact dissection approach while (23.66±3.88) min with the segmented dissection(t=-4.173, P=0.002). Immunofluorescence analysis showed all cochlear hair cells werevisible and intact in two groups. Conclusion: Cochlear basilar membrane can be dissected intact in a short time through both approaches. The approaches selection is dependent on the purpose of experiment and operators' experience.


Asunto(s)
Membrana Basilar/anatomía & histología , Cóclea/anatomía & histología , Disección/métodos , Animales , Técnica del Anticuerpo Fluorescente , Células Ciliadas Auditivas , Ratones , Ratones Endogámicos C57BL , Distribución Aleatoria
3.
Haematologica ; 105(3): 697-707, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31123034

RESUMEN

The pathogenesis of acute myeloid leukemia (AML) involves serial acquisition of mutations controlling several cellular processes, requiring combination therapies affecting key downstream survival nodes in order to treat the disease effectively. The BCL2 selective inhibitor venetoclax has potent anti-leukemia efficacy; however, resistance can occur due to its inability to inhibit MCL1, which is stabilized by the MAPK pathway. In this study, we aimed to determine the anti-leukemia efficacy of concomitant targeting of the BCL2 and MAPK pathways by venetoclax and the MEK1/2 inhibitor cobimetinib, respectively. The combination demonstrated synergy in seven of 11 AML cell lines, including those resistant to single agents, and showed growth-inhibitory activity in over 60% of primary samples from patients with diverse genetic alterations. The combination markedly impaired leukemia progenitor functions, while maintaining normal progenitors. Mass cytometry data revealed that BCL2 protein is enriched in leukemia stem/progenitor cells, primarily in venetoclax-sensitive samples, and that cobimetinib suppressed cytokine-induced pERK and pS6 signaling pathways. Through proteomic profiling studies, we identified several pathways inhibited downstream of MAPK that contribute to the synergy of the combination. In OCI-AML3 cells, the combination downregulated MCL1 protein levels and disrupted both BCL2:BIM and MCL1:BIM complexes, releasing BIM to induce cell death. RNA sequencing identified several enriched pathways, including MYC, mTORC1, and p53 in cells sensitive to the drug combination. In vivo, the venetoclax-cobimetinib combination reduced leukemia burden in xenograft models using genetically engineered OCI-AML3 and MOLM13 cells. Our data thus provide a rationale for combinatorial blockade of MEK and BCL2 pathways in AML.


Asunto(s)
Leucemia Mieloide Aguda , Proteómica , Apoptosis , Azetidinas , Compuestos Bicíclicos Heterocíclicos con Puentes , Línea Celular Tumoral , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Piperidinas , Proteínas Proto-Oncogénicas c-bcl-2/genética , Sulfonamidas
4.
Malays J Pathol ; 40(2): 111-119, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30173227

RESUMEN

INTRODUCTION: Thyroid cancer is the most common endocrine malignancy with more than 95% originating from follicular epithelial cells. Diagnostic dilemma may arise in occasional cases such as when an encapsulated nodule with a follicular growth pattern exhibits clear nuclei with grooves making it difficult to distinguish a follicular adenoma from encapsulated follicular variant papillary thyroid carcinoma. This study aimed to evaluate the diagnostic utility of an immunohistochemical marker, CD56, to distinguish between benign and malignant thyroid lesions. MATERIALS AND METHODS: We retrospectively studied CD56 expression in 54 benign and 54 malignant thyroid lesions using archival formalin fixed paraffin-embedded tissue blocks for the study period from January 2010 to December 2015, diagnosed in a tertiary hospital. RESULTS: CD56 was expressed in 52/54 (96.3%) of benign specimens and only 24/54 (44.4%) of malignant ones. The malignant specimens comprised 31 (57.4%) papillary thyroid carcinomas (PTC), 11 (20.3%) follicular carcinomas (FC), seven (13%) medullary thyroid carcinomas (MC), one (1.9%) poorly differentiated carcinoma (PC) and four (7.4%) anaplastic carcinomas (AC). CD56 was not expressed in 28/31 (90.3%) of the PTCs, 1/11 (9.1%) FCs, 1/4 (25%) of ACs while all MCs and the PD were positive. The benign group comprised nodular hyperplasias (29/54), lymphocytic thyroiditis (10/54), follicular adenomas (FA) (14/54) and one hyalinising trabecular tumour. CD56 was expressed in all the benign cases except one FA and one nodular hyperplasia. Thirteen of the 14 FAs were CD56 positive. The difference in expression between benign and malignant tumours was statistically significant as the p value was <0.01. CONCLUSION: CD56 is a potentially good immunohistochemical marker for differentiating papillary thyroid carcinoma from other benign follicular lesions of the thyroid especially in differentiating follicular variant PTC from FA in equivocal cases.


Asunto(s)
Adenoma/patología , Biomarcadores de Tumor/análisis , Antígeno CD56/biosíntesis , Neoplasias de la Tiroides/patología , Adenoma/diagnóstico , Adulto , Antígeno CD56/análisis , Diagnóstico Diferencial , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias de la Tiroides/diagnóstico
5.
Malays Orthop J ; 12(1): 42-44, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29725512

RESUMEN

The diagnosis of pathological fractures is on the rise. The morbidity involved does not only burden the patient and their families but it has a great toll on the healthcare system as well. Early identification of the patient at risk is an invaluable tool to cut cost and improve the patient's quality of life. Multiple renal pathologies have been highlighted in relation to the risk of pathological fractures; however, complications in renal tubular acidosis have been rarely documented. Nevertheless, prompt action with adequate and relevant patient education ultimately can reduce the associated morbidity. We present a case of poor control of the disease and its debilitating pathological fracture complications.

6.
Indian J Dent Res ; 28(5): 503-506, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29072211

RESUMEN

INTRODUCTION: Accredited social health activists (ASHAs) are the grassroot level health activists in the community who are involved in health education and community mobilization toward utilizing the health services. MATERIALS AND METHODS: A descriptive cross-sectional study was carried out to assess the oral health knowledge among ASHAs working in Guntur district of Andhra Pradesh, India. Five Primary Health Centers were randomly selected, and the total sample was 275. Categorical data were analyzed using Chi-square test. P ≤ 0.05 was considered to be statistically significant. RESULTS: The mean age was 32 ± 5.11 years and mean education was 9 ± 1.329 years of schooling. ASHAs were categorized into two groups based on their education levels, i.e., Group I whose education qualification is <10th class and Group II whose education qualification is above 10th class to observe any difference in knowledge based on their education. Overall knowledge among ASHAs was poor and also it was observed that both the groups were having poor knowledge regarding dental caries, calculus, dental plaque, oral cancer, and change of tooth brush. About 69.5% of the ASHAs were approached by public with dental problems, but only a few, i.e., 15.8% have referred the patients to the nearby dentist. CONCLUSION: As we know that most of the dental diseases are preventable, there is a dire need that ASHAs should be thoroughly educated in the aspects of oral health and diseases during their training period. This not only helps in creating awareness among them but also serves the ultimate purpose of improving the oral health of rural population.


Asunto(s)
Agentes Comunitarios de Salud , Escolaridad , Conocimientos, Actitudes y Práctica en Salud , Salud Bucal , Servicios de Salud Rural , Acreditación , Adulto , Estudios Transversales , Femenino , Humanos , India , Masculino , Población Rural , Recursos Humanos
7.
Zhonghua Yi Xue Za Zhi ; 97(15): 1140-1144, 2017 Apr 18.
Artículo en Chino | MEDLINE | ID: mdl-28427119

RESUMEN

Objective: To explore genetic characteristic of posterior cranial fossa morphology in families of Chiari malformation type Ⅰ (CMI). Methods: From April 2010 to May 2016, a total of 47 cases of CMI families (CMI group) and their 94 parents (CMI-P group)collected were retrospectively reviewed in Department of Spinal Surgery, Drum Tower Hospital, School of Medicine, Nanjing University.Another cohort of 50 asymptomatic adults was enrolled to serve as the control group.Patients with skull fracture or other diseases which can lead to secondary CMI were excluded.On mid-sagittal T2-weighted magnetic resonance (MR) imaging, four measurements were evaluated and compared between these three groups, including the length of cerebellar tonsillar descent, the area of posterior cranial fossa(PCF area), the area of the brain tissue in posterior cranial fossa (PCF tissue area), and the PCF crowdedness indexes (PCF tissue area/ PCF area×100%). Results: Totally 47 CMI patients (21 males and 26 females; mean age, 16.4 years), 94 parents (47 males and 47 females; mean age, 39.2 years) and 50 controls (23 males and 27 females; mean age, 22.3 years) were recruited in this study.Significant differences in all four indexes were found between CMI group and the control group.The length of cerebellar tonsillar descent were much bigger in CMI-P group than in the control group (1.5±2.2 mm vs -0.9±1.1 mm), with 7 cases reach the diagnostic criteria of Chiari malformation(≥5 mm) and one with syingomyelia.Compared to the control group, CMI-P group had smaller PCF area, and its PCF crowdedness indexes averaged 90.0% as between the control group (85.3%) and the CMI group (93.6%). Conclusions: In CMI families, parents have similar posterior cranial fossa abnormalities with their CMI children, presenting obviously narrow and crowded.Their PCF crowdedness indexes are between normal subjects and CMI patients, and their cerebellar tonsils are lower, even some parents are also CMI patients, suggesting genetic mechanisms involved in the development of CMI.


Asunto(s)
Malformación de Arnold-Chiari/genética , Fosa Craneal Posterior/patología , Pruebas Genéticas , Adolescente , Adulto , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
8.
Aliment Pharmacol Ther ; 39(10): 1003-32, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24641570

RESUMEN

BACKGROUND: There has been growing interest in the use of faecal microbiota transplantation (FMT) for the treatment of gastrointestinal and nongastrointestinal diseases. AIM: To review systematically the reported efficacy and safety of FMT in the management of gastrointestinal and nongastrointestinal disorders in adults and children. METHODS: The systematic review followed Cochrane and PRISMA recommendations. Available articles were identified using three electronic databases in addition to hand searching and contacting experts. Inclusion criteria were any reports of FMT therapy written in English. RESULTS: A total of 844 patients who had undergone FMT were identified from 67 published studies. The most common indications were refractory/relapsing Clostridium difficile infection (CDI) (76.3%) and inflammatory bowel disease (IBD) (13.2%). There has been only one placebo-controlled trial, a successful trial in 43 patients with recurrent CDI. Seven publications report FMT in paediatric patients with a total of 11 treated, 3 with chronic constipation and the remainder with recurrent CDI or ulcerative colitis (UC). 90.7% of patients with refractory/relapsing CDI were cured and 78.4% of patients with IBD were in remission after FMT. FMT therapy could also be effective in treatment of some nongastrointestinal disorders such as chronic fatigue syndrome. The only reported serious adverse event attributed to the therapy was a case of suspected peritonitis. CONCLUSIONS: Although more controlled trials are needed, faecal microbiota transplantation therapy shows promise in both adults and children with gastrointestinal diseases such as CDI and IBD.


Asunto(s)
Heces/microbiología , Enfermedades Gastrointestinales/terapia , Enfermedades Inflamatorias del Intestino/terapia , Adulto , Niño , Infecciones por Clostridium/terapia , Colitis Ulcerosa/terapia , Síndrome de Fatiga Crónica/terapia , Humanos , Microbiota , Recurrencia , Resultado del Tratamiento
9.
Oncogene ; 33(11): 1395-406, 2014 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-23604121

RESUMEN

Tartrate-resistant acid phosphatase 5 (ACP5), which is essential for bone resorption and osteoclast differentiation, promotes cell motility through the modulation of focal adhesion kinase phosphorylation. However, whether ACP5 contributes to the metastasis and progression of hepatocellular carcinoma (HCC) remains unknown. In this paper, a complementary DNA microarray, serial deletion, site-directed mutagenesis and a chromatin immunoprecipitation assays confirmed that ACP5 is a direct transcriptional target of Forkhead box M1 (FoxM1). ACP5 expression was markedly higher in HCC tissues compared with adjacent noncancerous tissues. ACP5 overexpression was correlated with microvascular invasion, poor differentiation and higher tumor-node-metastasis stage. HCC patients with positive ACP5 expression had poorer prognoses than those with negative ACP5 expression. A multivariate analysis revealed that ACP5 expression was an independent and significant risk factor for disease recurrence and reduced-patient survival following curative resection. Transwell assays and an orthotopic metastatic model showed that the upregulation of ACP5 promoted HCC invasion and lung metastasis, whereas ACP5 knockdown inhibited these processes. The knockdown of ACP5 significantly attenuated FoxM1-enhanced invasion and lung metastasis. Immunohistochemistry revealed that ACP5 expression was positively correlated with FoxM1 expression in human HCC tissues, and their coexpression was associated with poor prognoses. In summary, ACP5 is a direct transcriptional and functional target of FoxM1. This novel FoxM1/ACP5 signaling pathway promotes HCC metastasis and may be a candidate biomarker for prognosis and a target for new therapies.


Asunto(s)
Fosfatasa Ácida/fisiología , Carcinoma Hepatocelular/patología , Factores de Transcripción Forkhead/metabolismo , Isoenzimas/fisiología , Neoplasias Hepáticas/patología , Metástasis de la Neoplasia , Fosfatasa Ácida/metabolismo , Adulto , Femenino , Proteína Forkhead Box M1 , Humanos , Isoenzimas/metabolismo , Masculino , Persona de Mediana Edad , Pronóstico , Fosfatasa Ácida Tartratorresistente
10.
J Neurosci Res ; 92(2): 185-94, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24265160

RESUMEN

Transplanting neural stem cells (NSC) to the damaged brain has been regarded as a potential treatment for neurodegenerative diseases such as Alzheimer's disease (AD), a condition characterized by memory loss. We hypothesized that transplantation of NSC into the hippocampal regions of APP + PS1 transgenic (Tg) mice, a well-established model of AD, would enhance the expression of synaptic proteins, which may be helpful for improving cognitive function. Our results showed that NSC transplantation significantly improved spatial learning and memory function in Tg mice. The results obtained by real-time RT-PCR, immunofluorescence, and Western blot analyses demonstrated that the expression of synaptophysin (SYN) and that of growth-associated protein-43 (GAP-43) in Tg-NSC mice, 8 weeks after transplantation, were significantly improved compared with what was observed in Tg-Veh (control) mice. This finding was confirmed by the increase in the number of synapses in Tg-NSC mice as observed via electron microscopy. Our results suggest that NSC-induced changes can recover memory loss in APP + PS1 transgenic mice, possibly by establishing new neural circuits resulting from the engrafted NSC.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Proteína GAP-43/biosíntesis , Memoria , Células-Madre Neurales/trasplante , Sinaptofisina/biosíntesis , Animales , Western Blotting , Diferenciación Celular , Proliferación Celular , Modelos Animales de Enfermedad , Técnica del Anticuerpo Fluorescente , Ratones , Ratones Transgénicos , Células-Madre Neurales/citología , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trasplante de Células Madre
11.
Anaesth Intensive Care ; 33(6): 719-25, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16398375

RESUMEN

Ultrasound guidance allows real-time identification of relevant anatomy and needle position when performing brachial plexus regional anaesthesia. The aim of this investigation was to determine whether the use of surface ultrasound could improve the quality of brachial plexus anaesthesia for upper limb surgery. Forty patients were randomized to either conventional "landmark-based" plexus anaesthesia, or to an ultrasound-guided approach using a 13 mHz linear array transducer Both interscalene and axillary techniques were used. The use of ultrasound significantly improved the onset and completeness of sensory (P=0.011) and motor (P=0.002) block. Ultrasound guidance also significantly reduced (P=0.012) the incidence of paraesthesia during the performance of the blocks. Ultrasound guidance increases the quality of sensory and motor blockade in brachial plexus regional anaesthesia, and by reducing the incidence of paraesthesia during performance of the blocks, may confer greater safety.


Asunto(s)
Plexo Braquial/diagnóstico por imagen , Bloqueo Nervioso/métodos , Extremidad Superior/cirugía , Análisis de Varianza , Anestesia de Conducción/métodos , Anestésicos Locales/administración & dosificación , Plexo Braquial/efectos de los fármacos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Procedimientos Ortopédicos/métodos , Dimensión del Dolor , Probabilidad , Valores de Referencia , Medición de Riesgo , Factores de Tiempo , Ultrasonografía
12.
Hear Res ; 155(1-2): 1-8, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11335071

RESUMEN

The base of the cochlea is more vulnerable to trauma than the apex as seen in the pattern of hair cell damage by cisplatin or aminoglycosides. The differential vulnerability is maintained in organotypic cultures exposed directly to these drugs, suggesting there may be an intrinsic difference in sensitivity to damage along the cochlear spiral. We therefore investigated the survival capacity of isolated outer hair cells and strips dissected from different turns of the guinea pig organ of Corti in short-term culture. Cells were stained with fluorescent indicators of viable or dead cells, calcein-AM and ethidium homodimer. After 5 h at room temperature, up to 90% of outer hair cells from the apex survived, but less than 30% from the base. In contrast, basal inner hair cells remained viable, and supporting cells survived for at least 20 h. The difference in survival capacity between basal and apical outer hair cells coincided with a significantly lower level of the antioxidant glutathione in basal outer hair cells compared with apical outer hair cells. This suggested that basal outer hair cells may be more vulnerable to free-radical damage than apical outer hair cells. The survival of basal outer hair cells was significantly improved by addition of the radical scavengers n-acetyl cysteine, p-phenylenediamine, glutathione, mannitol or salicylate. The protection by antioxidants implies that the accelerated death of basal outer hair cells is due to free-radical damage. The results support an intrinsic susceptibility to free radicals that differs among cochlear cell populations. This differential provides a rational explanation for base-to-apex gradients observed in various forms of cochlear pathology.


Asunto(s)
Células Ciliadas Auditivas Externas/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Radicales Libres/toxicidad , Glutatión/metabolismo , Glutatión/farmacología , Cobayas , Células Ciliadas Auditivas Externas/lesiones , Células Ciliadas Auditivas Externas/patología , Técnicas In Vitro , Manitol/farmacología
13.
J Leukoc Biol ; 68(5): 757-64, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11073117

RESUMEN

We have identified a stimulatory monoclonal antibody (mAb) from autoimmune mice that selectively stimulates granulocyte colony-stimulating factor (G-CSF) gene expression in a mouse macrophage cell line. The induction was observed not only in the cell line, but also in normal peritoneal macrophages. This mAb bound to the monocyte/macrophage cell lines and pre-B leukemia cell lines, but also in normal peritoneal macrophages, whereas it did not bind to normal T and B cells in the spleen or fibroblastic cell lines. It could even bind to a human promyelocytic leukemia cell line, when they were differentiated into monocytic cells. On Western blotting, this mAb mainly recognized an approximately 30-kDa band and it was unique because there have been no reports of membrane-associated proteins with a similar molecular mass found in macrophages. These results suggest that there could be a specific gateway molecule to induce G-CSF in macrophages.


Asunto(s)
Anticuerpos Monoclonales , Regulación de la Expresión Génica , Factor Estimulante de Colonias de Granulocitos/biosíntesis , Factor Estimulante de Colonias de Granulocitos/genética , Macrófagos Peritoneales/fisiología , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/aislamiento & purificación , Antígenos/inmunología , Autoinmunidad/genética , Autoinmunidad/inmunología , Western Blotting , Línea Celular , Femenino , Citometría de Flujo , Regulación de la Expresión Génica/inmunología , Genes Reporteros , Humanos , Inmunización , Luciferasas/genética , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Endogámicos MRL lpr , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Ratas , Ratas Endogámicas WKY
14.
Hear Res ; 128(1-2): 112-8, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10082291

RESUMEN

We have previously shown gentamicin to form a redox-active iron chelate. This study investigates whether other aminoglycosides can likewise stimulate the generation of reactive oxygen species (free radicals). Kanamycin, neomycin and streptomycin were compared to gentamicin in intact cells and in cell-free in vitro assays using luminescence detection with lucigenin or luminol. Neutrophils and Epstein-Barr virus-transformed lymphoblastoid cells served as cell models in which a respiratory burst of superoxide was induced by phorbol ester. The addition of millimolar amounts of any of the aminoglycosides increased the luminescence significantly. The drugs also increased the formation of free radicals in an enzymatic (hypoxanthine-xanthine oxidase) and a non-enzymatic (phenazine methosulfate-NADH) superoxide-generating system. Half-maximal stimulation was reached with (0.4 mM gentamicin, and there was an absolute requirement for an electron donor, arachidonic acid. In both intact cells and cell-free systems, gentamicin-enhanced luminosity was suppressed by iron chelators. These results demonstrate that different aminoglycoside antibiotics can stimulate the formation of free radicals in biological and in cell-free systems. Luminescence detection is a convenient assay method to investigate the redox properties of these drugs.


Asunto(s)
Antibacterianos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Acridinas , Animales , Sistema Libre de Células , Senescencia Celular/fisiología , Gentamicinas/antagonistas & inhibidores , Gentamicinas/farmacología , Cobayas , Herpesvirus Humano 4/fisiología , Indicadores y Reactivos , Quelantes del Hierro/farmacología , Mediciones Luminiscentes , Luminol , Activación de Linfocitos/fisiología , Linfocitos/metabolismo , Linfocitos/virología , Neutrófilos/metabolismo
15.
Free Radic Biol Med ; 25(2): 189-95, 1998 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-9667495

RESUMEN

The attenuation of gentamicin-induced hearing loss by iron chelators and radical scavengers has recently been demonstrated in guinea pig in vivo. The present study investigated whether this protective treatment is effective against hearing loss and vestibular damage caused by other aminoglycosides. In a direct comparison, dihydroxybenzoate was chosen over deferoxamine because of its more effective action against gentamicin-induced hearing loss. Guinea pigs received daily injections of kanamycin (250 mg/kg/d) or streptomycin (300 mg/kg/d) for 23 d to induce severe cochlear or vestibular toxicity, respectively. Kanamycin injections resulted in a progressive threshold shift of 60 to 80 dB at 18 kHz, while streptomycin injections induced only a small threshold shift. In contrast, streptomycin abolished almost all vestibular responses. Coinjection of aminoglycosides with a mixture of dihydroxybenzoate (100 mg/kg/d) and mannitol (30 mg/kg/d) significantly attenuated kanamycin-induced hearing loss and protected against streptomycin-induced vestibulotoxicity. DHB/mannitol did not affect serum levels or the antibacterial efficacy of either aminoglycoside. This study supports the idea that iron and free radicals play a critical role in the toxic side effects of aminoglycoside antibiotics. Furthermore, the previously proposed therapeutic protection is not limited to gentamicin but applicable to other aminoglycosides as well.


Asunto(s)
Aminoglicósidos/antagonistas & inhibidores , Aminoglicósidos/toxicidad , Cóclea/efectos de los fármacos , Quelantes del Hierro/farmacología , Vestíbulo del Laberinto/efectos de los fármacos , Animales , Antibacterianos/antagonistas & inhibidores , Antibacterianos/toxicidad , Nitrógeno de la Urea Sanguínea , Peso Corporal/efectos de los fármacos , Creatinina/sangre , Deferoxamina/administración & dosificación , Deferoxamina/farmacología , Esquema de Medicación , Potenciales Evocados Auditivos del Tronco Encefálico/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Gentamicinas/administración & dosificación , Gentamicinas/toxicidad , Cobayas , Hidroxibenzoatos/administración & dosificación , Hidroxibenzoatos/farmacología , Kanamicina/administración & dosificación , Kanamicina/sangre , Kanamicina/toxicidad , Masculino , Manitol/administración & dosificación , Manitol/farmacología , Pruebas de Sensibilidad Microbiana , Reflejo Vestibuloocular/efectos de los fármacos , Albúmina Sérica/análisis , Estreptomicina/administración & dosificación , Estreptomicina/sangre , Estreptomicina/toxicidad
16.
J Biochem ; 121(5): 842-8, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9192723

RESUMEN

We purified and characterized glutaredoxin (thioltransferase), which catalyzes thiol/disulfide exchange reaction, for the first time in plants. The purification procedure employed an immunoabsorbent, antiglutaredoxin-Sepharose. Glutaredoxin was purified about 2,200-fold from rice bran and it appeared to be homogeneous on SDS-PAGE. MALDI-TOF mass spectrometry revealed that the protein has a molecular mass of 11,097.9 Da. Rice glutaredoxin consists of 105 amino acid residues, containing the tetrapeptide -Cys-Phe-Pro (Tyr)-Cys-, which constitutes the active site of Escherichia coli and mammalian glutaredoxins. Inactivation assay also indicated that cysteine residues are responsible for enzyme activity. Kinetic analyses revealed that the enzyme did not exhibit normal Michaelis-Menten kinetics. The enzyme has an optimum pH of about 8.7 with 2-hydroxyethyl disulfide as a substrate. In addition, rice glutaredoxin has dehydroascorbate reductase activity, like mammalian glutaredoxin.


Asunto(s)
Oryza/enzimología , Oxidorreductasas/análisis , Oxidorreductasas/aislamiento & purificación , Proteína Disulfuro Reductasa (Glutatión) , Secuencia de Aminoácidos , Reacciones Antígeno-Anticuerpo/inmunología , Activación Enzimática/fisiología , Glutarredoxinas , Concentración de Iones de Hidrógeno , Cinética , Datos de Secuencia Molecular , Pruebas de Neutralización , Oxidorreductasas/metabolismo , Proteínas de Plantas/análisis , Proteínas de Plantas/aislamiento & purificación
17.
Biosci Biotechnol Biochem ; 60(2): 335-7, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9063985

RESUMEN

A gene encoding the 13-kDa prolamin polypeptide was isolated from a rice genomic library (lambdaEMBL3) and the nucleotide sequence of an about 3-kbp EcoRI fragment was analyzed. The cloned gene (NRP33) codes for a protein composed of 156 amino acids, including a signal peptide of 19 amino acid residues and no intron is present in the genomic clone. The nucleotide sequence contains consensus TATA and CAAT boxes, and two polyadenylation signals. In addition, there are two conserved sequences named the -- 300 element and 10 consecutive repeats of the trinucleotide ATT in the 5' noncoding sequence.


Asunto(s)
ADN de Plantas/genética , Genes de Plantas , Oryza/genética , Proteínas de Plantas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Genoma de Planta , Intrones , Datos de Secuencia Molecular , Prolaminas , TATA Box
18.
Endocrinology ; 125(6): 3022-8, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2555134

RESUMEN

Associated with the generalized uterine growth stimulated by estradiol in the rat are specific responses including messenger RNA (mRNA) synthesis, protein synthesis, and peroxidase activity. The increase in peroxidase activity, although sensitive to inhibitors of RNA and protein synthesis, results from an estradiol-stimulated influx of eosinophils into the uterus. We postulated the existence of an estradiol-regulated uterine chemotactic factor, testing this by an in vitro chemotactic assay with eosinophils isolated from mature rats. Treatment of immature rats with 1 microgram estradiol for 24 h resulted in a significant increase in eosinophil chemotaxis compared to uterine extracts of vehicle-treated rats. This increase was seen as early as 3 h after estradiol administration and was maximal at 24 h. The magnitude of the chemotactic response was dependent on the dose of estradiol administered (1-100 micrograms). Estrone or estriol treatment resulted in chemotactic activity greater than control but less than estradiol. Direct addition of estradiol to extracts of control animals did not increase chemotaxis. The estradiol-stimulated chemotaxis was blocked by in vivo treatment with the antiestrogen tamoxifen and by inhibitors of RNA and protein synthesis. Analysis of extracts from estradiol-treated uteri shows that the chemotactic factor is heat labile, pronase sensitive, and has a mass of approximately 20 kilodaltons (kDa). These data suggest that the estradiol-stimulated influx of eosinophils into the rat uterus is mediated by the synthesis, modification, or release of a protein whose synthesis is estradiol receptor mediated.


Asunto(s)
Factores Quimiotácticos/biosíntesis , Eosinófilos/fisiología , Estrógenos/farmacología , Útero/metabolismo , Animales , Bioensayo , Factores Quimiotácticos/farmacología , Quimiotaxis de Leucocito/efectos de los fármacos , Estradiol/farmacología , Estriol/farmacología , Estrógenos/administración & dosificación , Estrona/farmacología , Femenino , Peroxidasa/metabolismo , Ratas , Ratas Endogámicas , Tamoxifeno/farmacología , Útero/efectos de los fármacos , Útero/crecimiento & desarrollo
19.
Am J Physiol ; 257(6 Pt 1): E848-54, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2558573

RESUMEN

Cardiovascular and renal actions of human calcitonin gene-related peptide II (or beta) (CGRP) and of human calcitonin (CT) infused intravenously for 1 h each (79 and 263 pmol.kg-1.h-1) have been compared in normal men (n = 10 for CGRP, n = 6 for CT and vehicle alone). CGRP lowered diastolic blood pressure by 26% and increased the heart rate by 35% and raised plasma levels of norepinephrine, epinephrine, and dopamine and renin activity (P less than 0.01). The fractional excretion rates (FE) of sodium and chloride were doubled (P less than 0.05-0.01) in the presence of an unaltered glomerular filtration rate. CT, on the other hand, did not affect the diastolic blood pressure, but the stimulation of diuresis and of the FE of sodium and chloride was more pronounced with CT than with CGRP (P less than 0.01). Moreover, CT lowered serum calcium levels and stimulated urinary adenosine 3',5'-cyclic monophosphate and phosphate excretion (P less than 0.01). In conclusion, the cardiovascular effects of CGRP are contrasted by weaker renal tubular actions of the neuropeptide in relation to CT.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/farmacología , Calcitonina/farmacología , Hemodinámica/efectos de los fármacos , Hormonas/sangre , Riñón/fisiología , Adulto , Aldosterona/sangre , Factor Natriurético Atrial/sangre , Presión Sanguínea/efectos de los fármacos , AMP Cíclico/orina , GMP Cíclico/orina , Diástole/efectos de los fármacos , Dopamina/sangre , Electrólitos/orina , Epinefrina/sangre , Tasa de Filtración Glomerular/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Riñón/efectos de los fármacos , Masculino , Norepinefrina/sangre , Proteínas Recombinantes/farmacología , Valores de Referencia , Renina/sangre , Sístole/efectos de los fármacos
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