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1.
Proc Natl Acad Sci U S A ; 118(12)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33731479

RESUMO

The negatively charged silicon monovacancy [Formula: see text] in 4H silicon carbide (SiC) is a spin-active point defect that has the potential to act as a qubit in solid-state quantum information applications. Photonic crystal cavities (PCCs) can augment the optical emission of the [Formula: see text], yet fine-tuning the defect-cavity interaction remains challenging. We report on two postfabrication processes that result in enhancement of the [Formula: see text] optical emission from our PCCs, an indication of improved coupling between the cavity and ensemble of silicon vacancies. Below-bandgap irradiation at 785-nm and 532-nm wavelengths carried out at times ranging from a few minutes to several hours results in stable enhancement of emission, believed to result from changing the relative ratio of [Formula: see text] ("dark state") to [Formula: see text] ("bright state"). The much faster change effected by 532-nm irradiation may result from cooperative charge-state conversion due to proximal defects. Thermal annealing at 100 °C, carried out over 20 min, also results in emission enhancements and may be explained by the relatively low-activation energy diffusion of carbon interstitials [Formula: see text], subsequently recombining with other defects to create additional [Formula: see text]s. These PCC-enabled experiments reveal insights into defect modifications and interactions within a controlled, designated volume and indicate pathways to improved defect-cavity interactions.

2.
Neuromodulation ; 26(5): 1030-1038, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36437161

RESUMO

OBJECTIVE: Spinal cord stimulation (SCS) is considered an effective interventional nonpharmacologic treatment option for several chronic pain conditions. Here we present the effects of the novel evoked compound action potential (ECAP) controlled closed-loop (ECAP-CL) SCS system on long-term sleep quality outcomes from the EVOKE study. MATERIALS AND METHODS: The EVOKE study is a double-blind, randomized, controlled clinical trial conducted at 13 sites in the United States (N = 134 patients). The clinical trial utilized SCS to manage chronic pain and compared novel ECAP-CL technology to open-loop SCS. Additionally, sleep quality data was collected using the Pittsburgh Sleep Quality Index (PSQI) at baseline and all study visits. RESULTS: The mean PSQI global score for ECAP-CL patients at baseline was 14.0 (n = 62; ± 0.5, SD 3.8), indicating poor sleep quality. Clinically meaningful and statistically significant reductions (p < 0.001) in the global PSQI scores were noted at 12 months (n = 55; 5.7 ± 0.6, SD 4.2). A total of 76.4% of ECAP-CL patients met or exceeded Minimal Clinically Important Difference from baseline in PSQI at 12 months. Additionally, 30.9% of ECAP-CL patients achieved "good sleep quality" scores (PSQI ≤ 5), and 29.1% achieved sleep quality remission. "Normative" sleep scores were observed in 29.6% of ECAP-CL patients at 12 months, and these scores were better than the US general population. Additionally, ECAP-CL patients achieved statistically significant changes from baseline (p < 0.01) across all seven subcomponent scores of PSQI at 12 months. CONCLUSIONS: ECAP-CL SCS elicits consistent neural activation of the target leading to less variability in long-term therapy delivery. In the EVOKE study, this resulted in ECAP-CL patients demonstrating clinically superior and sustained pain relief. Results from this study provide new evidence of long-term improvement in sleep quality and quantity in patients with chronic pain resulting from the use of this novel ECAP-CL SCS technology. CLINICAL TRAIL REGISTRATION: The Clinicaltrials.gov registration number for the study is NCT02924129.


Assuntos
Dor Crônica , Estimulação da Medula Espinal , Humanos , Dor Crônica/terapia , Dor Crônica/etiologia , Potenciais de Ação/fisiologia , Qualidade do Sono , Estimulação da Medula Espinal/métodos , Potenciais Evocados/fisiologia , Resultado do Tratamento , Medula Espinal/fisiologia
3.
Opt Express ; 28(10): 14536-14546, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403492

RESUMO

Titanium nitride (TiN) has been identified as a promising refractory material for high temperature plasmonic applications such as surface plasmon polaritons (SPPs) waveguides, lasers and light sources, and near field optics. Such SPPs are sensitive not only to the highly metallic nature of the TiN, but also to its low loss. We have formed highly metallic, low-loss TiN thin films on MgO substrates to create SPPs with resonances between 775-825 nm. Scanning near-field optical microscopy (SNOM) allowed imaging of the SPP fringes, the accurate determination of the effective wavelength of the SPP modes, and propagation lengths greater than 10 microns. Further, we show the engineering of the band structure of the plasmonic modes in TiN in the mid-IR regime and experimentally demonstrate, for the first time, the ability of TiN to support Spoof Surface Plasmon Polaritons in the mid-IR (6 microns wavelength).

4.
Tumour Biol ; 37(1): 437-46, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26224476

RESUMO

Human tissue kallikrein-related peptidases (KLK) are a group of 15 serine proteases which have been investigated as potential cancer biomarkers. This study determined the prognostic significance of KLK 11 and 15 expression levels in gastric carcinoma specimens. Expression of KLK11 and KLK15 was assessed by immunohistochemistry staining on a tissue microarray constructed from 113 gastrectomy specimens from patients with gastric carcinoma. To minimize inter-observer variability, expression levels were quantified using an automated algorithm. Epithelial and stromal staining were assessed separately. Both KLK11 and KLK15 were expressed in gastric carcinoma. There was no significant correlation between either KLK11 or KLK15 expression and the presence of lymph node metastases or Lauren classification (intestinal vs. diffuse). Higher levels of KLK11 expression in gastric carcinoma were associated with significantly worse overall survival (p = 0.008), and a multivariate analysis showed that it had prognostic value independent of tumor stage and differentiation (p = 0.004). Variations in KLK15 expression were not significantly associated with prognosis. KLK11 shows promise as a potential independent prognostic marker for gastric carcinoma.


Assuntos
Adenocarcinoma/metabolismo , Carcinoma/metabolismo , Calicreínas/química , Serina Endopeptidases/metabolismo , Neoplasias Gástricas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Calicreínas/genética , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Medicina de Precisão , Prognóstico , Modelos de Riscos Proporcionais , Serina Endopeptidases/genética , Análise Serial de Tecidos , Adulto Jovem
5.
Rev Chil Pediatr ; 87(6): 500-503, 2016.
Artigo em Espanhol | MEDLINE | ID: mdl-26921150

RESUMO

INTRODUCTION: Congenital surfactant deficiency is a condition infrequently diagnosed in newborns. A clinical case is presented of surfactant protein B deficiency. A review is performed on the study, treatment and differential diagnosis of surfactant protein deficiencies and infant chronic interstitial lung disease. CASE REPORT: The case is presented of a term newborn that developed respiratory distress, recurrent pulmonary opacification, and a transient response to the administration of surfactant. Immunohistochemical and genetic studies confirmed the diagnosis of surfactant protein B deficiency. CONCLUSIONS: Pulmonary congenital anomalies require a high index of suspicion. Surfactant protein B deficiency is clinically progressive and fatal in the majority of the cases, similar to that of ATP binding cassette subfamily A member 3 (ABCA3) deficiency. Protein C deficiency is insidious and may present with a radiological pulmonary interstitial pattern. Due to the similarity in the histological pattern, genetic studies help to achieve greater certainty in the prognosis and the possibility of providing adequate genetic counselling.


Assuntos
Proteinose Alveolar Pulmonar/congênito , Proteína B Associada a Surfactante Pulmonar/deficiência , Surfactantes Pulmonares/administração & dosagem , Síndrome do Desconforto Respiratório do Recém-Nascido/etiologia , Diagnóstico Diferencial , Humanos , Recém-Nascido , Masculino , Proteinose Alveolar Pulmonar/complicações , Proteinose Alveolar Pulmonar/diagnóstico , Proteinose Alveolar Pulmonar/tratamento farmacológico , Síndrome do Desconforto Respiratório do Recém-Nascido/genética
6.
Biol Chem ; 395(9): 1087-93, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25153389

RESUMO

The prognosis of patients following surgery for gastric cancer is often poor and is estimated using traditional clinicopathological parameters, which can be inaccurate predictors of future survival. Kallikreins are a group of serine proteases, which are differentially expressed in many human tumors and are being investigated as potential cancer biomarkers. This study assessed the prognostic utility of human tissue kallikrein-like peptidases 6 and 10 (KLK6 and KLK10) and correlated their expression with histopathological and clinical parameters in gastric cancer. We constructed a gastric tumor tissue microarray from 113 gastrectomy specimens and quantified KLK6 and KLK10 expression using immunohistochemistry. To overcome the problem of inter-observer variability and subjectivity in immunohistochemistry interpretation, a whole-slide scanned image of the tissue microarray was analyzed using an automated algorithm to quantify staining intensity. KLK6 expression was positively correlated with nodal involvement (p=0.002) and was predictive of advanced-stage disease (p<0.05). Kaplan-Meier survival curves revealed that tumors expressing high levels of KLK6 were significantly associated with significantly lower overall survival (p=0.04). KLK10 overexpression was also a predictor of advanced-stage disease (p<0.01), but was not significantly correlated with lymph node involvement or survival period. Our results show the potential ability of KLK6 as a prognostic marker for gastric cancer.


Assuntos
Calicreínas/metabolismo , Neoplasias Gástricas/metabolismo , Calicreínas Teciduais/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/patologia , Adulto Jovem
7.
Rev Chil Pediatr ; 85(3): 304-11, 2014 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-25697247

RESUMO

INTRODUCTION: It has been reported that feeding tolerance in preterm infants is associated with an early passage of meconium. Prospective, randomized or historical control studies that stimulate meconium evacuation have reported varied results. This study was intented to evaluate the use of enemas to speed up meconium evacuation, facilitating feeding tolerance. PATIENTS AND METHOD: A controlled multicenter randomized trial that evaluated the use of physiological saline enemas with glycerol (0.8 ml glycerol + 3 ml saline or 1 ml glycerol + 5 ml saline depending on babies weighing less or more than 800 g at birth, respectively) versus simulation. This procedure was performed in the first 96 hours of life in infants with birth weight between 500 and 1,250 g. Maternal (preterm delivery, clinical chorioamnionitis, gestational hypertension, administration of magnesium sulfate and prenatal corticosteroids, fetal Doppler altered, type of delivery, gender, weight and gestational age, assessment of Apgar and need for assisted ventilation and oxygenotherapy) and nutritional history (age when feeding volumes of 100 ml/kg/day and full enteral feeding were reached, age to remove meconium, number of days on parenteral nutrition, weight at 28 days, weekly volumes of breast milk and preterm formula) were described. RESULTS: No significant differences were obtained regarding the age to reach full enteral intake or 100 ml/kg/day were found among the 101 patients in the study. Also, no differences in the following secondary variables are observed: number of episodes of late sepsis with or without positive blood culture, hyperbilirubinemia, necrotizing enterocolitis and intraventricular hemorrhage. CONCLUSIONS: The routine use of saline enemas and glycerin in this study does not alter the enteral feeding tolerance in very low birth weight preterm infants.


Assuntos
Enema/métodos , Nutrição Enteral/métodos , Mecônio/metabolismo , Glicerol/administração & dosagem , Humanos , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Estudos Prospectivos , Cloreto de Sódio/administração & dosagem , Resultado do Tratamento
8.
Mol Vis ; 19: 1413-21, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23825921

RESUMO

PURPOSE: The purpose of this study was to investigate (i) the effect of diabetes on retinal ganglion cell death in diabetic dogs and mice, (ii) the effect of prolonged glycemic control on diabetes-induced death of retinal ganglion cells, (iii) whether retinal ganglion cell death in diabetes is associated with degeneration of retinal capillaries, and (iv) the effect of diet on diabetes-induced degeneration of retinal ganglion cells in mice. METHODS: Diabetes was induced in dogs using streptozotocin, and levels of glycemic control (good, moderate, and poor) were maintained for 5 years. Diabetes was studied in two mouse models (diabetes induced in C57Bl/6J mice using streptozotocin and spontaneously diabetic Ins2Akita mice). Retinal ganglion cell death was investigated by counting the number of axons from the ganglion cells in the optic nerve and with terminal transferase deoxyuridine triphosphate nick-end labeling and annexin V staining in mice. RESULTS: As reported previously, the development and severity of vascular lesions of diabetic retinopathy in diabetic dogs were strongly associated with glycemic control. Loss of retinal ganglion cells was extensive in dogs kept in poor glycemic control, and was essentially prevented in diabetic dogs kept in good glycemic control for the 5 years of study. In contrast, "moderate" glycemic control (intermediate between poor and good glycemic control) caused a significant increase in vascular pathology, but did not cause loss of retinal axons in the optic nerve. Using this validated optic nerve axon counting method, the two mouse models of diabetic retinopathy were studied to assess ganglion cell death. Despite 10 months of diabetes (a duration that has been shown to cause retinal capillary degeneration in both models), neither mouse model showed loss of optic nerve axons (thus suggesting no loss of retinal ganglion cells). Likewise, other parameters of cell death (terminal transferase deoxyuridine triphosphate nick-end labeling and annexin V labeling) did not suggest ganglion cell death in diabetic C57Bl/6J mice, and ganglion cell death was not increased by a different commercial diet. CONCLUSIONS: Retinal ganglion cell death in diabetic dogs is significantly inhibited by good or even moderate glycemic control. The finding that diabetic dogs in moderate glycemic control had appreciable vascular disease without apparent retinal ganglion cell degeneration does not support the postulate that neural degeneration causes the vascular pathology. Studies of diabetic mice in our colony again fail to find evidence of ganglion cell death due to prolonged diabetes in this species.


Assuntos
Capilares/patologia , Diabetes Mellitus Experimental/patologia , Hiperglicemia/complicações , Degeneração Retiniana/complicações , Degeneração Retiniana/patologia , Células Ganglionares da Retina/patologia , Vasos Retinianos/patologia , Animais , Axônios/patologia , Axônios/ultraestrutura , Capilares/metabolismo , Diabetes Mellitus Experimental/complicações , Cães , Hiperglicemia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nervo Óptico/patologia , Nervo Óptico/ultraestrutura , Células Ganglionares da Retina/metabolismo , Vasos Retinianos/metabolismo
9.
Heliyon ; 7(12): e08507, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34917803

RESUMO

Increase in the auditory abilities of children with cochlear implants (CIs) has led to an improvement in naming tasks, although divergent results are still being reported; this strongly suggests that further studies are needed. The study aims to compare the responses in a picture-naming activity between the complete population of children aged 5 to 7 with cochlear implants in Catalonia -Spain- (N = 31), without developmental problems, and a matched sample of 31 children with typical hearing. A picture-naming task was used to assess their lexical naming abilities. The results show that children with CIs provide more non-responses, they produce fewer words correctly, they require a longer reaction time and they commit more picture-naming errors than children with typical hearing. The auditory age does significantly affect the results, but not the type of implant. In spite of the hearing gain achieved with the cochlear implant and the listening experience progressively achieved in distinct contexts, further explicit work on lexical naming in speech-therapy intervention is clearly required.

10.
Mol Ecol ; 18(16): 3458-70, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19627490

RESUMO

Biological invasions usually start with a small number of founder individuals. These founders are likely to represent a small fraction of the total genetic diversity found in the source population. Our study set out to trace genetically the geographical origin of the horse-chestnut leafminer, Cameraria ohridella, an invasive microlepidopteran whose area of origin is still unkown. Since its discovery in Macedonia 25 years ago, this insect has experienced an explosive westward range expansion, progressively colonizing all of Central and Western Europe. We used cytochrome oxidase I sequences (DNA barcode fragment) and a set of six polymorphic microsatellites to assess the genetic variability of C. ohridella populations, and to test the hypothesis that C. ohridella derives from the southern Balkans (Albania, Macedonia and Greece). Analysis of mtDNA of 486 individuals from 88 localities allowed us to identify 25 geographically structured haplotypes. In addition, 480 individuals from 16 populations from Europe and the southern Balkans were genotyped for 6 polymorphic microsatellite loci. High haplotype diversity and low measures of nucleotide diversities including a significantly negative Tajima's D indicate that C. ohridella has experienced rapid population expansion during its dispersal across Europe. Both mtDNA and microsatellites show a reduction in genetic diversity of C. ohridella populations sampled from artificial habitats (e.g. planted trees in public parks, gardens, along roads in urban or sub-urban areas) across Europe compared with C. ohridella sampled in natural stands of horse-chestnuts in the southern Balkans. These findings suggest that European populations of C. ohridella may indeed derive from the southern Balkans.


Assuntos
Variação Genética , Genética Populacional , Lepidópteros/genética , Aesculus , Animais , DNA Mitocondrial/genética , Ecossistema , Europa (Continente) , Marcadores Genéticos , Haplótipos , Repetições de Microssatélites , Análise de Sequência de DNA
13.
Virchows Arch ; 449(6): 730-3, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17106708

RESUMO

Ciliated hepatic foregut cysts (CHFC) are rare cystic lesions of the liver composed of a ciliated pseudostratified columnar epithelium with mucous cells, connective tissue, and smooth muscles bundles. We report the first case of CHFC with extensive squamous metaplasia without dysplasia or carcinoma. A unilocular, avascular, hypoechoic 60-mm liver lesion located in segment IV was detected by ultrasonography in a 31-year-old woman. The cyst was surgically removed and was lined mainly by a regular squamous epithelium without keratin formation. After extensive sampling, a ciliated pseudostratified columnar epithelium with some alcian blue-positive goblet cells was identified. The lesion was totally examined and there was no epithelial dysplasia or carcinoma. Squamous epithelium is very rare in hepatic foregut cysts and may degenerate into squamous carcinoma. Squamous epithelium is also described in biliary cysts. When squamous epithelium is identified in a liver cyst, an extensive sampling is recommended to identify possible foci of squamous carcinoma and to classify more precisely the histological type of the lesion. Because some cases of squamous carcinoma have been described in CHFC, surgical removal of the lesion may be more appropriate than close follow-up or sclerosing therapy.


Assuntos
Cistos/patologia , Hepatopatias/patologia , Adulto , Cílios/patologia , Feminino , Humanos , Metaplasia , Receptores de Progesterona/análise
14.
J Neural Transm Suppl ; (71): 205-13, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17447431

RESUMO

Owing to its ability to undergo one-electron reactions, iron transforms the mild oxidant hydrogen peroxide into hydroxyl radical, one of the most reactive species in nature. Deleterious effects of iron accumulation are dramatically evidenced in several neurodegenerative diseases. The work of Youdim and collaborators has been fundamental in describing the accumulation of iron confined to the substantia nigra (SN) in Parkinson's disease (PD) and to clarify iron toxicity pathways and oxidative damage in dopaminergic neurons. Nevertheless, how the mechanisms involved in normal neuronal iron homeostasis are surpassed, remain largely undetermined. How nigral neurons survive or succumb to iron-induced oxidative stress are relevant questions both to know about the etiology of the disease and to design neuroprotective strategies. In this work, we review the components of neural iron homeostasis and we summarize evidence from recent studies aimed to unravel the molecular basis of iron accumulation and dyshomeostasis in PD.


Assuntos
Ferro/metabolismo , Doença de Parkinson/metabolismo , Animais , Homeostase/fisiologia , Humanos
15.
Rev. chil. reumatol ; 37(1): 23-33, 2021. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1400380

RESUMO

Introducción: El dolor musculoesquelético (ME) es un motivo de consulta común en la infancia originado en su mayoría por causas banales. Entre las causas menos frecuentes encontramos las patologías reumatológicas y neoplásicas. Se presentan tres casos clínicos que debutaron con artritis o artralgia en los cuales el diagnóstico final fue neoplásico. Casos clínicos: el primer caso fue una Leucemia Linfoblástica Aguda (LLA) de alto riesgo, el segundo caso fue un sarcoma de Ewing y el tercer caso fue una LLA común. Dos de los casos tuvieron evolución desfavorable con fallecimiento. Revisión de la literatura: Se describen hallazgos que deben hacer sospechar una causa neoplásica tales como el dolor ME desproporcionado, alteraciones en el hemograma, velocidad de eritrosedimentación globular y lactato deshidrogenasa elevados, y radiografía con alteraciones sugerentes. Conclusiones: Frente a un dolor ME en el niño se debe tener presente las causas neoplásicas a pesar de su baja frecuencia dado su mal pronóstico.


Introduction: Musculoskeletal (MS) pain is a common complaint in childhood, usually caused by trivial ailments. Among less frequent causes we may find rheumatological and neoplastic pathologies. We present 3 clinical cases in which a rheumatological cause was initially suspected, as they started out with arthritis or arthralgia, but where the diagnosis was finally a neoplasm. Clinical cases: the first case was a high-risk Acute Lymphoblastic Leukemia (ALL), the second case was a Ewing's sarcoma, and the third case was a common ALL. Two of the cases had unfavourable outcomes and passed away. Literature review: Findings that should make us suspect neoplastic causes are disproportionate MS pain, altered hemogram, elevated erythrocyte sedimentation rate and lactate dehydrogenase, and an x ray with suggestive alterations. Conclusions: When faced with MS pain in children, neoplastic causes must be taken into account despite their low frequency given the poor prognosis associated with the diagnosis.


Assuntos
Humanos , Masculino , Criança , Doenças Musculoesqueléticas/etiologia , Doenças Musculoesqueléticas/diagnóstico por imagem , Neoplasias Hematológicas/complicações , Radiografia , Cintilografia , Técnicas de Laboratório Clínico , Diagnóstico Diferencial , Dor Musculoesquelética/etiologia
18.
Hum Pathol ; 46(4): 541-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25649006

RESUMO

Kallikreins are a family of serine proteases that are linked to malignancy of different body organs with potential clinical utility as tumor markers. In this study, we investigated kallikrein-related peptidase 6 (KLK6) and KLK10 expression in early gastroesophageal junction adenocarcinoma and Barrett esophagus (BE) with and without dysplasia. Immunohistochemistry revealed significantly increased KLK6 expression in early invasive cancer compared with dysplastic (P = .009) and nondysplastic BE (P = .0002). There was a stepwise expression increase from metaplasia to dysplasia and invasive tumors. Significantly higher KLK10 was seen in dysplastic lesions compared with metaplasia but not between dysplastic lesions and invasive cancers. KLK6 staining intensity was increased at the invasive front (P = .006), suggesting its role in tumor invasiveness. Neither KLK6 nor KLK10 was significantly associated with other prognostic markers, including depth of invasion, indicating their potential as independent biomarkers. Our results should be interpreted with caution due to limited sample size. There was a significant correlation between KLK6 and KLK10 expression both at the invasive front and within the main tumor, indicating a collaborative effect. We then compared KLK6 and KLK10 messenger RNA expression between metaplastic and cancerous tissues in an independent data set of esophageal carcinoma from The Cancer Genome Atlas. KLK6 and KLK10 may be useful markers and potential therapeutic targets in gastroesophageal junction tumors.


Assuntos
Adenocarcinoma/diagnóstico , Biomarcadores Tumorais/metabolismo , Neoplasias Esofágicas/diagnóstico , Junção Esofagogástrica/metabolismo , Calicreínas/metabolismo , Peptídeo Hidrolases/metabolismo , Adenocarcinoma/metabolismo , Adulto , Idoso , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Esofágicas/metabolismo , Feminino , Humanos , Imuno-Histoquímica/métodos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico
19.
Neuroscience ; 107(2): 293-300, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11731103

RESUMO

Effects of ATP on substance P immunoreactivity were examined in cultured dorsal root ganglion neurons. We found that treatment of dorsal root ganglion neurons with ATP significantly depleted substance P immunoreactivity on the neurites and somata of the neurons. The effects of ATP were significantly inhibited by the purinergic P2 receptor antagonists suramin (30 microM) and pyridoxal-phosphate-6-azophenyl-2',4'-disulfonic acid (10 microM). We also showed that ATP-induced depletion of substance P immunoreactivity from dorsal root ganglion neurons depended on the entry of Ca(2+). In a spinal cord slice preparation, we also found the internalization of neurokinin-1/substance P receptors in many dorsal horn neurons following the application of ATP or alpha,beta-methylene-ATP. Together these results indicate that activation of P2X receptors may result in release of substance P from primary afferent neurons.


Assuntos
Trifosfato de Adenosina/fisiologia , Neurônios Aferentes/metabolismo , Receptores Purinérgicos P2/fisiologia , Substância P/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Células Cultivadas , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Imuno-Histoquímica , Microscopia Confocal , Microscopia de Fluorescência , Células do Corno Posterior/metabolismo , Agonistas do Receptor Purinérgico P2 , Antagonistas do Receptor Purinérgico P2 , Ratos , Ratos Sprague-Dawley , Receptores da Neurocinina-1/metabolismo
20.
Neuroreport ; 11(16): 3589-92, 2000 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-11095524

RESUMO

Triple fluorescent staining for P2X1 and P2X3 subunits and isolectin I-B4 (IB4) were performed on acutely dissociated rat DRG neurons. Immunoreactivity for P2X1 and P2X3 subunits was present separately or together in DRG neurons. P2X1 immunoreactivity was present in both IB4-positive and IB4-negative cells. When combining patch-clamp recordings with immunostaining for the P2X1 and P2X3 subunits on single recorded cells, ATP-evoked fast currents were shown to be present on DRG neurons that have immunoreactivity for the P2X3 subunit only, the P2X1 subunit only, or both P2X1 and P2X3 subunits. These results raised a possibility that, in addition to the P2X3 receptor subunit, the P2X1 subunit may also contribute to functional P2X receptors with fast kinetics in DRG neurons.


Assuntos
Trifosfato de Adenosina/farmacologia , Potenciais Evocados/fisiologia , Gânglios Espinais/fisiologia , Neurônios/fisiologia , Receptores Purinérgicos P2/fisiologia , Animais , Potenciais Evocados/efeitos dos fármacos , Gânglios Espinais/citologia , Imuno-Histoquímica , Cinética , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp , Ratos , Receptores Purinérgicos P2/análise , Receptores Purinérgicos P2X , Receptores Purinérgicos P2X3
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