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Background: Radiation therapy (RT) plays an important role in management of pediatric central nervous system (CNS) malignancies. Centers are increasingly utilizing pencil beam scanning proton therapy (PBS-PT). However, the risk of brainstem necrosis has not yet been reported. In this study, we evaluate the rate of brainstem necrosis in pediatric patients with CNS malignancies treated with PBS-PT.Material and methods: Pediatric patients with non-hematologic CNS malignancies treated with PBS-PT who received dose to the brainstem were included. All procedures were approved by the institutional review board. Brainstem necrosis was defined as symptomatic toxicity. The actuarial rate was analyzed by the Kaplan Meier method.Results: One hundred and sixty-six consecutive patients were reviewed. Median age was 10 years (range 0.5-21 years). Four patients (2.4%) had prior radiation. Median maximum brainstem dose in the treated course was 55.4 Gy[RBE] (range 0.15-61.4 Gy[RBE]). In patients with prior RT, cumulative median maximum brainstem dose was 98.0 Gy [RBE] (range 17.0-111.0 Gy [RBE]). Median follow up was 19.6 months (range, 2.0-63.0). One patient who had previously been treated with twice-daily radiation therapy and intrathecal (IT) methotrexate experienced brainstem necrosis. The actuarial incidence of brainstem necrosis was 0.7% at 24 months (95% CI 0.1-5.1%).Conclusion: The rate of symptomatic brainstem necrosis was extremely low after treatment with PBS-PT in this study. Further work to clarify clinical and dosimetric parameters associated with risk of brainstem necrosis after PBS-PT is needed.
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Tronco Encefálico/efectos de la radiación , Neoplasias del Sistema Nervioso Central/radioterapia , Terapia de Protones/efectos adversos , Adolescente , Astrocitoma/radioterapia , Tronco Encefálico/patología , Niño , Preescolar , Ependimoma/radioterapia , Femenino , Humanos , Lactante , Estimación de Kaplan-Meier , Masculino , Meduloblastoma/radioterapia , Necrosis/epidemiología , Necrosis/etiología , Terapia de Protones/métodos , Dosis de Radiación , Traumatismos por Radiación/complicaciones , Reirradiación/efectos adversos , Adulto JovenRESUMEN
In India, cross-breeding of indigenous cattle with exotic cattle such as Holstein Friesian and Jersey has been going on since last four decades to improve milk production. Although it has led to increased milk yield, the subfertility in male cross-bred progeny has remained a significant problem. Epigenetic modifications (DNA methylation, histone modifications and chromatin remodelling) are regarded as key players influencing gene expression. DAZL gene plays an important role in germline development and gametogenesis. The methylation and mRNA expression level of this gene have been significantly negatively correlated in the testes of cattle-yak hybrids and their parents. This study analysed the methylation profile of DAZL gene promoter in bull spermatozoa in an attempt to speculate its role in cross-bred cattle subfertility. Semen samples from Sahiwal, Holstein Friesian and Frieswal bulls (Sahiwal X Holstein Friesian) with varying semen motility parameters were collected, and DNA was isolated. Methylation-specific primers were used to amplify part of promoter and exon 1 of DAZL gene using bisulphite-converted DNA. The amplified products were sequenced after cloning in pTZ57R/T vector. Sequence analysis revealed significantly higher DNA methylation of DAZL gene in Frieswal bulls with poor motility (28.26%) as compared to medium (15.21%) and high motility phenotype (6.52%). In pure-bred counterparts, Sahiwal and Holstein Friesian, epigenetic marks were more in the former (15.21%) than the latter (4.34%), but in both cases, the values were lower as compared to the poor motility Frieswal bulls. This suggests that differential hypermethylation of the CpG islands could possibly influence reproductive parameters in bovines.
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Bovinos/fisiología , Metilación de ADN , Regiones Promotoras Genéticas , Proteínas de Unión al ARN/metabolismo , Análisis de Semen/veterinaria , Semen/fisiología , Animales , Predisposición Genética a la Enfermedad , Infertilidad Masculina/genética , Masculino , Proteínas de Unión al ARN/genética , Motilidad Espermática , EspermatozoidesRESUMEN
Obstetric anaesthesiologists play a pivotal role as peripartum physicians steering the team of obstetric healthcare providers towards a continuum of medical education, enhanced training and safer patient care. However, in resource-limited countries, deficiency of human resources and hence services available poses challenges to those attempting to reduce maternal mortality rates. Measures to fill the gap include creating a cadre of uniformly well-trained and certified non-physician anaesthesia providers (NPAPs) supervised by a physician obstetric anaesthesiologist and well-equipped rural and urban health care facilities. The Association of Obstetric Anaesthesiologists of India needs to upscale their outreach programs with regular knowledge updates and practical skill training to the NPAPs, medical graduates and postgraduate doctors in these regions. A combination of strong local administrative will, legislation for the provision of essential supplies and a global collaborative effort using checklists and protocols may help to stem gaps in the provision of safe maternal care.
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Anestesiología , Servicios de Salud Materna , Embarazo , Femenino , Humanos , Recursos Humanos , Mortalidad Materna , IndiaRESUMEN
Regional anesthesia is the preferred technique for Cesarean delivery. Strict aseptic precautions should be taken; otherwise, infectious complications including abscess formation, meningitis and necrotizing fasciitis may result. We report a case of a 26-year-old post-partum female who presented with necrosis of the skin of back following spinal anesthesia, which was administered for Cesarean delivery 5 days prior at a private nursing home. On presentation, she was drowsy, appeared dehydrated and febrile. Examination of her back revealed necrosis of skin extending from just below the scapula to the gluteal region. Debridement of skin over the back was performed, and intravenous antibiotics started. After three debridements following which skin grafting was performed, she made complete recovery. Infectious complications following regional anesthesia are rare, and most of the literature focuses on colonization of epidural catheters or epidural abscess. There is no report of necrotizing fasciitis following spinal anesthesia so far. Sources of infection that are suspected in our case include: local anesthetic solution used for subcutaneous infiltration, nonadherence to aseptic precautions, skin flora of patient, endogenous source and nasopharyngeal flora of anesthesiologist. We considered each possibility, and the most likely cause in our case appears to be infection from an already-used vial of a local anesthetic agent. Local anesthetics have bacteriostatic properties, but infection may still be transmitted through contaminated solutions. The present case highlights the importance of maintaining strict aseptic precautions, avoiding reusing multidose vials and early recognition of this complication as timely intervention can be lifesaving.
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Anestesia Obstétrica/efectos adversos , Anestesia Raquidea/efectos adversos , Fascitis Necrotizante/etiología , Adulto , Antibacterianos/uso terapéutico , Cesárea , Desbridamiento , Contaminación de Medicamentos , Fascitis Necrotizante/tratamiento farmacológico , Femenino , Humanos , Embarazo , Choque/complicaciones , Infecciones Estreptocócicas/etiologíaRESUMEN
Cardiorespiratory arrest due to severe hypothermia may require prolonged cardiopulmonary resuscitation whilst the patient is rewarmed. There are reported cases of successful resuscitation with good neurological outcomes after prolonged arrests and resuscitation up to 9 h. However, in the majority of these cases, extracorporeal life support was used to maintain perfusion and rewarm the patient. Here, we report a case of successful cardiopulmonary resuscitation lasting 6.5 h, following cardiac arrest secondary to severe hypothermia, with rewarming using an Arctic Sun™ 5000. The Arctic Sun 5000 is a targeted temperature management device which is conventionally used to prevent hyperthermia post-cardiac arrest. In this report, we discuss the reasons why the device was used in this case and the effects of severe hypothermia on cardiac arrest management. We believe that this is the longest reported successful cardiopulmonary resuscitation in a severely hypothermic patient without the use of extracorporeal life support.
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The hexagonal close packed surface of gold shows a 22 × 3 "herringbone" surface reconstruction which makes it unique among the (111) surfaces of all metals. This long-range energetically favored dislocation pattern appears in response to the strong tensile stress that would be present on the unreconstructed surface. Adsorption of molecular and atomic species can be used to tune this surface stress and lift the herringbone reconstruction. Here we show that herringbone reconstruction can be controllably lifted in ultrahigh vacuum at cryogenic temperatures by precise hot electron injection in the presence of hydrogen molecules. We use the sharp tip of a scanning tunneling microscope (STM) for charge carrier injection and characterization of the resulting chain nanostructures. By comparing STM images, rotational spectromicroscopy and ab initio calculations, we show that formation of gold atomic chains is associated with release of gold atoms from the surface, lifting of the reconstruction, dissociation of H2 molecules, and formation of surface hydrides. Gold hydrides grow in a zipper-like mechanism forming chains along the [11Ì 0] directions of the Au(111) surface and can be manipulated by further electron injection. Finally, we demonstrate that Au(111) terraces can be transformed with nearly perfect terrace selectivity over distances of hundreds of nanometers.
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BACKGROUND: Phosphoinositide (PI) 3-kinase and its second messenger products, phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P(3)) and phosphatidylinositol 3,4-bisphosphate (PtdIns(3,4)P(2)), play important roles in signalling processes crucial for cell movement, differentiation and survival. Previously, we isolated a 32kDa PtdIns(3,4,5)P(3)-binding protein from porcine leukocytes. This protein contains an amino-terminal Src homology 2 (SH2) domain and a carboxy-terminal pleckstrin homology (PH) domain, and is identical to the recently described DAPP1 (also known as PHISH or Bam32) protein. Here, we characterised the subcellular distribution of DAPP1 in response to cell stimulation. RESULTS: When expressed transiently in porcine aortic endothelial (PAE) cells, DAPP1 translocated from the cytosol to the plasma membrane in response to platelet-derived growth factor (PDGF). This translocation was dependent on both PI 3-kinase activity and an intact DAPP1 PH domain. Following recruitment to the plasma membrane, DAPP1 entered the cell in vesicles. Similar responses were seen in DT40 chicken B cells following antibody treatment, and Rat-1 fibroblasts following epidermal growth factor (EGF) or PDGF treatment. Colocalisation studies in PAE cells suggested entry of DAPP1 by endocytosis in a population of early endosomes containing internalised PDGF-beta receptors. DAPP1 also underwent PI 3-kinase-dependent phosphorylation on Tyr139 in response to PDGF stimulation, and this event was involved in the vesicular response. CONCLUSIONS: This is the first report of plasma-membrane recruitment and endocytosis of a PI 3-kinase effector protein in response to cell stimulation. The results suggest a novel role for DAPP1 in endosomal trafficking or sorting.
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Proteínas Sanguíneas/metabolismo , Proteínas Portadoras/metabolismo , Endocitosis/fisiología , Ácidos Grasos/metabolismo , Lipoproteínas/metabolismo , Proteínas de la Membrana/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Animales , Linfocitos B/citología , Linfocitos B/efectos de los fármacos , Linfocitos B/metabolismo , Sitios de Unión , Transporte Biológico , Proteínas Sanguíneas/genética , Proteínas Portadoras/genética , Línea Celular , Membrana Celular/metabolismo , Pollos , Activación Enzimática , Ácidos Grasos/genética , Lipoproteínas/genética , Proteínas de la Membrana/genética , Fosfoproteínas/metabolismo , Fosforilación , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Factor de Crecimiento Derivado de Plaquetas/farmacología , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Transducción de Señal , Porcinos , Vesículas Transportadoras/metabolismo , Tirosina/metabolismoRESUMEN
OBJECTIVE: Assess suitability of remote self-monitoring of blood pressure with an innovative use of technology in detecting raised blood pressure in pregnancy. STUDY DESIGN: Assess ease of use and safety of the newly developed kit which included a Bluetooth enabled blood pressure machine and an android based mobile phone. The phone was modified to have only one application in it which showed the blood pressure readings with a traffic light system. The study was a proof of concept for wider use of the kit. We provided 50 women who were admitted with the kit. We assessed ease of use of the blood pressure machine and accuracy of readings including remote transfer to a computer. MAIN OUTCOME MEASURE: Technological feasibility and acceptance by women. RESULTS: The technology provides accurate data and visual cues including safe remote transfer instantaneously. 90% of the women agreed that the Kit was simple to use and 78% would prefer this model of testing at home. CONCLUSION: In a relatively resource rich setting the machine can reduce the number of patient visits for women who are at risk for preeclampsia. In resource poor settings it helps to triage resources to women who need it the most. It also is a valuable tool for research. Studies of the Kit in both developed and developing world will be needed to show reduction in perinatal and maternal morbidity or mortality secondary to preeclampsia.
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Determinación de la Presión Sanguínea/métodos , Aplicaciones Móviles , Preeclampsia/diagnóstico , Autocuidado/métodos , Telemedicina/métodos , Determinación de la Presión Sanguínea/instrumentación , Estudios de Factibilidad , Femenino , Humanos , Aceptación de la Atención de Salud , Embarazo , Embarazo de Alto Riesgo/fisiología , Autocuidado/instrumentación , Teléfono Inteligente , Telemedicina/instrumentaciónRESUMEN
BACKGROUND: Previous studies show that rapid tryptophan depletion reverses the effects of therapy with serotonergic, but not noradrenergic, antidepressant drugs in patients with remitted nonseasonal depression. The objective of this study was to investigate the effects of rapid tryptophan depletion in patients with seasonal affective disorder (SAD) that was in clinical remission after light therapy. METHODS: Patients who met DSM-III-R criteria for recurrent major depressive episodes, seasonal (winter) pattern (equivalent to SAD), were treated with a standard course of light therapy. Ten patients with SAD in clinical remission after light therapy underwent rapid tryptophan depletion in a placebo-controlled, double-blind crossover study. Behavioral ratings and plasma tryptophan levels were obtained before and after rapid tryptophan depletion. RESULTS: Plasma total and free tryptophan levels were significantly reduced to 20% of normal levels by the rapid tryptophan depletion. The depletion session resulted in significant increases in depression scores compared with the sham control session. Six of 10 patients had a clinically significant relapse of their depression following the tryptophan depletion session. CONCLUSIONS: Rapid tryptophan depletion appears to reverse the antidepressant effect of bright light therapy in patients with SAD. This suggests that the therapeutic effects of bright light in SAD may involve a serotonergic mechanism.
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Fototerapia , Trastorno Afectivo Estacional/psicología , Triptófano/sangre , Adulto , Aminoácidos/administración & dosificación , Aminoácidos/metabolismo , Método Doble Ciego , Femenino , Alimentos Formulados , Humanos , Masculino , Persona de Mediana Edad , Placebos , Escalas de Valoración Psiquiátrica , Trastorno Afectivo Estacional/sangre , Trastorno Afectivo Estacional/fisiopatología , Serotonina/metabolismo , Serotonina/fisiologíaRESUMEN
Noradrenergic and dopaminergic mechanisms have been proposed for the pathophysiology of seasonal affective disorder (SAD). We investigated the effects of catecholamine depletion using alpha-methyl-para-tyrosine (AMPT), an inhibitor of tyrosine hydroxylase, in patients with SAD in natural summer remission. Nine drug-free patients with SAD by DSM-IV criteria, in summer remission for at least eight weeks, completed a double-blind, crossover study. Behavioral ratings and serum HVA and MHPG levels were obtained for 3-day sessions during which patients took AMPT or an active control drug, diphenhydramine. The active AMPT session significantly reduced serum levels of HVA and MHPG compared with the control diphenhydramine session. The AMPT session resulted in higher depression ratings with all nine patients having significant clinical relapse, compared with two patients during the diphenhydramine session. All patients returned to baseline scores after drug discontinuation. Catecholamine depletion results in significant clinical relapse in patients with SAD in the untreated, summer-remitted state. AMPT-induced depressive relapse may be a trait marker for SAD, and/or brain catecholamines may play a direct role in the pathogenesis of SAD.
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Catecolaminas/deficiencia , Inhibidores Enzimáticos/farmacología , Trastorno Afectivo Estacional/fisiopatología , alfa-Metiltirosina/farmacología , Afecto/efectos de los fármacos , Estudios Cruzados , Dopamina/sangre , Dopamina/metabolismo , Método Doble Ciego , Femenino , Humanos , Masculino , Norepinefrina/sangre , Norepinefrina/metabolismo , Remisión Espontánea , Trastorno Afectivo Estacional/inducido químicamente , Trastorno Afectivo Estacional/psicología , Estaciones del Año , Tirosina 3-Monooxigenasa/antagonistas & inhibidoresRESUMEN
A crude extract from Ascaris suum was infused into the teat canal of heifers to serve as an irritant or an antigens. The cells present in the mammary gland following such stimulation were assessed over a period of 2 weeks. Prior to stimulation there were few cells, predominantly macrophages, however, by 12 h post-stimulation a larger number of eosinophils and neutrophils were present. The eosinophils, which represented approximately 50% of the total population, could be purified by Ficoll-Hypaque flotation and nylon or glass wool column filtration to yield a population consisting of over 90% eosinophils. Surface marker studies on the purified eosinophils revealed that they contained both Fc and complement receptors.
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Eosinófilos/inmunología , Animales , Sitios de Unión , Mama/citología , Bovinos , Separación Celular , Proteínas del Sistema Complemento , Femenino , Fragmentos Fc de Inmunoglobulinas , Formación de RosetaRESUMEN
OBJECTIVE: Many patients with seasonal affective disorder (SAD) have dysfunctional eating behaviors. Conversely, many women with bulimia nervosa have marked winter worsening of mood and bulimic symptoms. Controlled studies of light therapy in SAD and in bulimia nervosa have shown beneficial effects on mood and binge/purge symptoms. We explored the clinical use of light therapy in women with SAD who also had comorbid bulimia nervosa. METHOD: Twenty-two female patients diagnosed using DSM-IV criteria with both bulimia nervosa and major depressive disorder with a seasonal (winter) pattern were treated with an open design, 4-week trial of light therapy (10,000 lux fluorescent light box with an ultraviolet filter, 30 to 60 minutes per day in the early morning). Patients were assessed before and after treatment with depression scales and with binge/purge diaries. RESULTS: Light therapy resulted in significant improvement in mood, with a mean 56% reduction in 29-item Hamilton Rating Scale for Depression scores following treatment (p < .001). The frequency of binges and purges per week also significantly decreased (p < .001) from baseline by a mean of 46% and 36%, respectively. Two (9%) of 22 patients became abstinent of binge/ purge episodes, compared with 10 (45%) of 22 patients who met criteria for remission of depressive symptoms. The light therapy was well tolerated by patients. CONCLUSION: These results suggest that therapeutic effects of light therapy on mood and bulimic symptoms in patients with SAD and comorbid bulimia nervosa are sustained over at least 4 weeks. However, the low abstinence rate in bulimic symptoms indicates that light therapy may be most effectively used as an adjunctive treatment to medications and/or psychotherapy for bulimia nervosa.
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Bulimia/terapia , Fototerapia , Trastorno Afectivo Estacional/terapia , Adolescente , Adulto , Bulimia/diagnóstico , Bulimia/epidemiología , Comorbilidad , Femenino , Fluoxetina/uso terapéutico , Fluvoxamina/uso terapéutico , Humanos , Sistemas Multiinstitucionales , Inventario de Personalidad/estadística & datos numéricos , Placebos , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Estudios Retrospectivos , Trastorno Afectivo Estacional/diagnóstico , Trastorno Afectivo Estacional/epidemiología , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
A rosette inhibition test was developed using pig lymphocytes and sheep red blood cells. Antilymphocyte serum (ALS) in the presence of complement inhibited rosette formation by greater than 95% at 1/250 declining to no inhibition at 1/8000. Sera obtained from a total of 14 pregnant sows before and 1, 2, 3 and 4 wk after mating were tested for their ability to augment the rosette depression caused by ALS. In one experiment in which the responses of 4 pregnant sows were compared to 4 non-pregnant sows by discriminant analysis, sera were classified correctly in 83% of the samples taken from either pregnant or non-pregnant sows. When the more usual method of calculating the rosette inhibition titre was used, the responses of sera from pregnant pigs were classified with 31% accuracy and those from non-pregnant pigs with 80% accuracy. In a second experiment, sera from 10 pregnant sows were classified with 25% accuracy using the rosette inhibition titre. Thus 4 of these pigs were classified as non-pregnant by this method. Data from the second experiment were not suitable for discriminant analysis. It was concluded that there was some factor present in the sera of pregnant pigs, particularly by 3 or 4 wk post-mating, which could be detected by the rosette inhibition test. However, the test is not sensitive enough to allow specific diagnosis of early pregnancy in pigs.
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Pruebas Inmunológicas de Embarazo/veterinaria , Porcinos , Animales , Eritrocitos/inmunología , Estudios de Evaluación como Asunto , Femenino , Embarazo , Pruebas Inmunológicas de Embarazo/métodos , Formación de Roseta , Factores de TiempoRESUMEN
The insulin-like growth factor binding proteins (IGFBPs) are polypeptides which are thought to modulate the bioactivity of IGF-I and IGF-II, and may also have activities independent of the IGFs. The expression patterns of IGFBPs-1, -3, -4, and -6 in midgestational rodents were analyzed using in situ hybridization to begin to characterize the role of these IGFBPs during development. All IGFBPs are expressed at least as early as rat embryonic day 14 (e14), and each has a unique pattern of expression. IGFBP-1 mRNA is expressed by the liver throughout mid and late gestation. IGFBP-3 mRNA is expressed at high levels in the urogenital tract, several muscle groups, and the nasal epithelia. IGFBP-3 transcripts are also expressed at lower levels by many non-neural tissue types, including the liver, stomach, and heart. IGFBP-4 is abundantly expressed by many tissues in the developing embryo, with the notable exceptions of the spinal cord, specific cartilage groups, and the thymic cortex. IGFBP-6 is expressed in the liver by e14, and also by a previously unrecognized cell population surrounding developing cartilage. Taken together these observations suggest distinct roles in development for each of the IGFBPs.
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Proteínas Portadoras/biosíntesis , Desarrollo Embrionario y Fetal , Expresión Génica , ARN Mensajero/biosíntesis , Animales , Northern Blotting , Embrión de Mamíferos , Edad Gestacional , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina , Proteína 4 de Unión a Factor de Crecimiento Similar a la Insulina , Proteína 6 de Unión a Factor de Crecimiento Similar a la Insulina , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor II del Crecimiento Similar a la Insulina/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Especificidad de Órganos , RatasRESUMEN
Three micro-enzyme-linked immunosorbent assay (micro-ELISA) systems were developed and evaluated for detection of specific free circulating antigen and circulating immune-complexes (CICs) of 8 kDa antigen in the sera of patients with hydatidosis. All (100%) the sera of 30 confirmed positive cases of hydatidosis had detectable levels of antigen in the acid-treated sera. However, 23 (77%) and 26 (87%) sera of 30 confirmed cases had free as well as CICs of 8 kDa antigen in the untreated and in the polyethylene glycol (PEG) precipitated sera, respectively. None of the sera from other patients with parasitic infections or viral hepatitis had any detectable levels of 8 kDa antigen in the untreated, acid-treated or PEG-precipitated serum samples. The investigations, therefore, suggested that the demonstration of circulating antigen employing monospecific antibodies to affinity purified 8 kDa antigen in acid-treated sera is more efficient as compared to detection of free circulating antigen or CICs in the untreated or in the PEG-precipitated sera which could provide a specific immunodiagnostic tool for ongoing hydatid infection.
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Anticuerpos Antihelmínticos/inmunología , Complejo Antígeno-Anticuerpo/sangre , Antígenos Helmínticos/inmunología , Equinococosis/diagnóstico , Echinococcus/inmunología , Animales , Antígenos Helmínticos/aislamiento & purificación , Cromatografía de Afinidad , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Valor Predictivo de las PruebasRESUMEN
beta-Alanine (beta-ALa) is a structural analog of the putative inhibitory transmitters gamma-aminobutyric acid (GABA) and glycine. beta-ALa itself depresses firing in cultured mouse spinal cord (SC) neurons, by selectively increasing membrane conductance to chloride ions. Patch clamp recordings now reveal that beta-ALa-sensitive chloride channels in SC cells can open to at least 5 conductance states, 4 of which are very similar to states seen when GABA or glycine is applied to these cells. However, a large, 80 pS conductance state is activated at detectable frequency only in the presence of beta-ALa itself.
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Alanina/farmacología , Cloruros/fisiología , Proteínas de la Membrana/fisiología , Médula Espinal/fisiología , Animales , Canales de Cloruro , Embrión de Mamíferos , Técnicas In Vitro , Potenciales de la Membrana/efectos de los fármacos , Ratones , Médula Espinal/citologíaRESUMEN
Patch-clamp methods were used to compare biophysical properties of anion channels activated by taurine and gamma-aminobutyric acid in the membrane of cultured mouse spinal neurons. Outside-out patches were voltage clamped at -80 mV at a temperature of 21-23 degrees C. Bath application of GABA (1.5-2 microM) or taurine (5-40 microM) induced chloride-dependent single-channel currents in 14/20 patches tested. Amplitude distributions of these currents showed peaks corresponding to conductance levels of 8, 16, 27 and 46 pS. Only a few percent of GABA-induced events reached the 46 pS level, while 30% of taurine-induced currents were of this size. The average lifetime of taurine-activated channels in the open state was 1.0 +/- 0.07 ms, significantly shorter than the corresponding value for GABA (1.6 +/- 0.08 ms). Taurine-induced currents were abolished by 10 microM strychnine, but persisted in the presence of 50 microM bicuculline.
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Canales Iónicos/fisiología , Médula Espinal/fisiología , Taurina/farmacología , Animales , Células Cultivadas , Cloruros/fisiología , Canales Iónicos/efectos de los fármacos , Potenciales de la Membrana/efectos de los fármacos , Ratones , Médula Espinal/efectos de los fármacos , Ácido gamma-Aminobutírico/farmacologíaRESUMEN
Mass spectrometry occupies a central position in most current protein identification schemes. So-called 'mass fingerprinting' techniques rely on composite mass patterns of proteolytic fragments, or dissociation products thereof, to query databases. Keys to successful analysis of ever smaller amounts are sensitivity and complete spectral information, both of which depend for a large part on proper sample preparation. Clean-up and concentration of peptide mixtures over eppendorf gel loading tips filled with chromatographic media (i.e. 'micro-tips') are believed to be quite useful in this regard. We have studied quantitative and qualitative aspects of polypeptide extraction using these small manual devices. Optimization of sample volume and additives, micro-tip bed volume, and eluent composition and volume, all contribute to effective recovery (approximately 65-70%, on average). Improper digest conditions can, in fact, lead to far bigger losses, suggesting the need for at least trace amounts of Zwittergent 3-16. Of particular interest is our finding that partial fractionation, obtained by two-step micro-tip elution, generally results in more and better signals during subsequent mass analysis. Thus, by using optimized micro-tips, in combination with adequate sample handling and instrumentation, direct mass spectrometric identification can be routinely and successfully done in any resource facility type setting.
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Cromatografía Líquida de Alta Presión/métodos , Péptidos/aislamiento & purificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Secuencia de Aminoácidos , Cromatografía Líquida de Alta Presión/instrumentación , Endopeptidasas/metabolismo , Formiatos , Glucosafosfato Deshidrogenasa/análisis , Glucosafosfato Deshidrogenasa/metabolismo , Datos de Secuencia Molecular , Fragmentos de Péptidos/análisis , Fragmentos de Péptidos/química , Saccharomyces cerevisiae/enzimología , Solventes , Tripsina/metabolismoRESUMEN
Immunological cross-reactivity was established between salivary gland extract antigens of Hyalomma anatolicum anatolicum (H.a.a) and Boophilus microplus (B.m.), using native-polyacrylamide gel electrophoresis (native-PAGE), immunoblotting, DOT-enzyme immunoassay (DOT-EIA) and in vivo intra-dermal skin test revealing immediate type hypersensitivity swelling reaction. Native-PAGE revealed six proteins in common of molecular weights of 60, 66, 148, 264, 300 and > 300 kDa in the salivary gland extract (SGE) of both the ticks. Four additional bands of molecular weights of 56, 64, 120 and 220 kDa were present in H.a.a. but absent in B.m. Immunoblot assay of native-PAGE transblotted proteins of H.a.a., using mice anti-H.a.a. SGE and anti-B.m. SGE immune serum revealed a common protein of 66 kDa. In DOT-EIA, anti-H.a.a. or anti-B.m. SGE immune serum gave similar antibody titres against the SGE antigens of either tick species. Intradermal inoculation of the SGE antigens of either species on cross-bred calves (Bos indicus x Bos taurus) immunized to H.a.a. or B.m. ticks produced a strong, immediately hypersensitivity skin swelling reaction.
Asunto(s)
Proteínas y Péptidos Salivales/inmunología , Garrapatas/inmunología , Animales , Antígenos/administración & dosificación , Antígenos/inmunología , Antígenos/aislamiento & purificación , Bovinos , Reacciones Cruzadas , Electroforesis en Gel de Poliacrilamida , Femenino , Técnicas para Inmunoenzimas , Ratones , Ratones Endogámicos BALB C , Peso Molecular , Conejos , Proteínas y Péptidos Salivales/administración & dosificación , Proteínas y Péptidos Salivales/aislamiento & purificaciónRESUMEN
Development of acquired immunity in cross-bred (Bos indicus x Bos taurus) calves against Hyalomma anatolicum anatolicum, a tick vector of bovine tropical theileriosis was studied using ascaris extract (AE), an immunomodulator of IgE responses, along with the tick salivary gland extract (SGE) antigens in Freund's incomplete adjuvant (FIA) emulsion. Calves immunised with SGE + FIA showed significant rejection (47.4 +/- 2.8%) of larvae, whereas only marginal rejection (12.47 +/- 1.5%) of nymphs was observed. In contrast, calves immunised with the immunomodulator AE in addition to SGE + FIA showed significant enhanced rejection of nymphs (50.25 +/- 5.2%), while the rejection of larvae was only slightly higher (55.8 +/- 11.4%), and not statistically different. In addition, incorporation of the immunomodulator AE also resulted in significant enhancement in the percentage recovery of abnormally fed larvae and nymphs. This abnormal feeding was characterised by their white to pale-yellow colour instead of the dark-grey colour of normally fed ticks. It may possibly be attributed to their inability to gain access to the blood vessels owing to the host immunological reaction at the bite sites. Consequently, the ticks fed on extravascular fluid devoid of red blood cells resulting in their white to pale-yellow colour. Difference in the disease transmission potential of normally and abnormally fed ticks is of future interest. Sera from all the immunised calves after 2 weeks of immunisation were positive for anti-tick SGE antibodies in the dot enzyme immunoassay (DOT-EIA). The immunised calves were positive for immediate type hypersensitivity (ITH) skin reaction on intradermal inoculation of the tick SGE antigens. There was no apparent difference in the DOT-EIA antibody titres between the two immunised groups. However, ITH skin swelling was significantly higher in AE + SGE + FIA immunised calves. The study indicates that use of the AE as an immunomodulator along with the tick SGE antigens enhanced anti-tick immunity.