Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
J Environ Radioact ; 277: 107464, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38851006

RESUMEN

Demand for accurate estimation of coastal blue carbon sequestration rates in a regular interval has recently surged due to the increasing awareness of nature-based climate solutions to alleviate adverse impacts stemming from the recent global warming. The robust estimation method is, however, far from well-established. The international community requires, moreover, to quantify its effect of "management." This article tries to provide the environmental isotope community with basic biophysical features of coastal blue carbon ecosystems to identify a suitable set of environmental isotopes for promoting coastal ocean-based climate solutions. This article reviews (i) the primary biophysical characteristics of coastal blue carbon ecosystems and hydrology, (ii) their consequential impact on the accumulation and preservation of organic carbon (OC) in the sediment column, (iii) suitable environmental isotopes to quantifying the sedimentary organic carbon accumulation, outwelling of the carbon-containing byproducts of decomposition of biogenic organic matter and acid neutralizing alkalinity produced in situ sediment to the offshore. Above-ground biomass is not cumulative over the years except for mangrove forests within coastal blue carbon systems. Non-gaseous carbon sequestration and loss occur mainly as a form of sediment organic carbon (SOC) and dissolved carbon in an intertidal and subtidal bottom sediment body in a slow, patchy, and dispersive way, on which this article focuses. Investigating environmental radionuclides is probably the most cost-effective effort to contribute to defining the offshore spatial extent of coastal blue carbon systems except for seagrass beds (e.g., Ra isotopes), to quantify millimeter per year scale carbon accretion and loss within the systems (e.g., 7Be, 210Pb) and a liter per meter of coastline per a day scale water movement from the systems (Ra isotopes). A millimeter-scale spatial and an annual (or less) time-scale resolution offered by the use of environmental isotopes would equip us with a novel tool to enhance the carbon storage capacity of the coastal blue carbon system.


Asunto(s)
Secuestro de Carbono , Humedales , Monitoreo del Ambiente/métodos , Carbono , Ecosistema , Sedimentos Geológicos/química
2.
Artículo en Chino | MEDLINE | ID: mdl-31550760

RESUMEN

Objective: To investigate the value of acoustic parameters in the voice therapy for patients with unilateral vocal cord paralysis (UVCP). Methods: From May 2015 to April 2018, 51 patients with UVCP and 59 healthy controls in Department of Otorhinolaryngology Head and Neck Surgery, Tianjin First Central Hospital, were involved in this research retrospectively. The UVCP patients were diagnosed with stroboscopic laryngoscopy. The minimum glottal area (MGA) was calculated by KIPS software when the people were pronouncing/i:/. The fundamental frequency (F0), Jitter, Shimmer and NHR were detected by CSL4500 multiple acoustic voice analyzer. Results: MGA of UVCP patients was much higher than that of healthy control (male: 433.68±64.52 vs. 294.41±51.82, t=9.23, P=0.000; female: 498.80±73.42 vs. 302.03±76.54, t=13.21, P=0.000), which meaned vocal cord insufficiency.After voice therapy, MGA reduced significantly (male: 288.48±55.09, female: 258.22±57.17, t=24.41 and 31.22, P=0.000 vs. pre-therapy). MGA of untreated patients decreased in varying degrees. Compared with the voice therapy group, the MGA decreased in a significantly lower extent (24.25±22.91 vs. 188.31±54.37, t=8.97, P=0.000). The F0, Jitter, Shimmer and NHR raised significantly in UVCP patients group (P=0.000 vs. healthy control group), and they were reduced by voice therapy (all P<0.05). Each of the four acoustic parameters was relative with MGA, r=0.551, 0.867, 0.853 and 0.875 in turn, P=0.001, 0.000, 0.000, and 0.000. Conclusion: MGA and acoustic parameters can reflect the acoustic features of UVCP patients, which are useful tools in the UVCP assessment and voice therapy.


Asunto(s)
Acústica , Parálisis de los Pliegues Vocales , Femenino , Humanos , Laringoscopía , Masculino , Estudios Retrospectivos , Resultado del Tratamiento , Parálisis de los Pliegues Vocales/diagnóstico , Parálisis de los Pliegues Vocales/terapia , Pliegues Vocales/patología , Calidad de la Voz , Entrenamiento de la Voz
3.
Artículo en Chino | MEDLINE | ID: mdl-29871279

RESUMEN

Objective:To explore the application of narrow band imaging(NBI) technology in laryngeal tumor.Method:From Appril 2014 to Otober 2016, three hundred and twenty-two patients with suspected laryngeal cancer or precancerous lesions were enrolled in the First Central Hospital of Tianjin. Each patient was examined by electronic nasopharyngolaryngoscope under white light and NBI model. The sensitivity, specificity and accuracy of laryngeal tumor diagnosis under white light mode and NBI mode was compared based on pathological results. Result:The sensitivity, specificity and accuracy of white light mode in laryngeal tumor diagnosis were 77.17%,62.07% and 74.36%, respectively whereas the NBI model were 92.91%,77.59% and 90.06%, respectively.The sensitivity and accuracy of NBI model in laryngeal tumor diagnosis were significantly higer than white light model(P<0.05),but not the specificity. Conclusion:The electronic nasopharyngolaryngoscope of NBI technology not only found early lesions of laryngeal cancer, but also can improve the sensitivity and accuracy of laryngeal tumor diagnosis.


Asunto(s)
Neoplasias Laríngeas/diagnóstico por imagen , Imagen de Banda Estrecha , Humanos , Laringoscopía , Laringe , Sensibilidad y Especificidad
5.
Genet Mol Res ; 14(1): 2860-7, 2015 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-25867435

RESUMEN

Numerous studies have evaluated the association between TCF7L2 gene polymorphisms (rs12255372 and rs7903146) and breast cancer risk. However, the results have been inconsistent. Therefore, in the current study, we performed a meta-analysis. A systematically literature search of the PubMed and EMBASE databases was conducted in November 2013, and the reference lists of articles were retrieved. A summary odds ratio (OR) with its 95% confidence interval (CI) were calculated to evaluate the strength of association. Publication bias was investigated using Begg's funnel plot. Meta-analysis was performed using STATA package version 12.0. A total of 4 case-control studies met our inclusion criteria, including 4600 cases and 5289 controls. Overall, TCF7L2 gene polymorphisms were significantly associated with an increased risk of breast cancer in genetic comparison models (rs12255372 for GG vs GT: OR = 0.90, 95%CI = 0.83-0.98; rs7903146 for CC vs TT: OR = 0.75, 95%CI = 0.63-0.90, CC vs CT: OR = 0.88, 95%CI = 0.81-0.97, dominant model: OR = 1.16, 95%CI = 1.06-1.27, recessive model: OR = 0.79, 95%CI = 0.67-0.94). This meta-analysis demonstrated that TCF7L2 gene polymorphisms (rs12255372 and rs7903146) are associated with an increased susceptibility to breast cancer. However, further studies including large sample sizes are needed to validate this association.


Asunto(s)
Neoplasias de la Mama/genética , Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple , Proteína 2 Similar al Factor de Transcripción 7/genética , Estudios de Casos y Controles , Femenino , Humanos , Oportunidad Relativa , Factores de Riesgo
6.
Neuroscience ; 238: 252-7, 2013 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-23485814

RESUMEN

The present study examined the roles of ventrolateral orbital cortex (VLO) 5-HT1, 5-HT2, 5-HT3, 5-HT4, 5-HT5, 5-HT6 and 5-HT7 receptor subtypes in mediating 5-HT-induced antiallodynic actions in the rat spared nerve injury (SNI) pain model. Changes in paw withdrawal threshold (PWT) were measured using von-Frey filaments. Microinjection of 5-HT (2, 5 and 10µg, in 0.5µl) into the VLO depressed allodynia induced by SNI, and the PWT increased in a dose-dependent manner. Microinjection of selective 5-HT1A, 5-HT2, 5-HT3, 5-HT4, 5-HT5A, 5-HT6 and 5-HT7 receptor antagonists, 1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl] piperazine hydrobromide (NAN-190) (10µg), cyproheptadine (50ng), granisetron hydrochloride (granisetron) (10µg), 1-[2-[(methylsulfonyl)-amino]ethyl]-4-piperidinyl]methyl1-methyl-1H-indole-3-carboxylate (GR113808) (5µg), SB699551 dihydrochloride (SB699551) (10µg), SB258585 dihydrochloride (SB258585) (2µg) or SB269970 hydrochloride (SB269970) (10µg) into the VLO 5-min prior to 5-HT (10µg) injection, all antagonized the 5-HT-induced inhibition of allodynia. In addition, these antagonists applied alone to VLO did not influence allodynia. These results suggest that although 5-HT1-7 receptor subtypes in the VLO do not have a tonic modulatory action on the allodynia induced by SNI, they are involved in mediating the depression of the SNI allodynia produced by injection of 5HT into VLO.


Asunto(s)
Lóbulo Frontal/efectos de los fármacos , Hiperalgesia/metabolismo , Umbral del Dolor/efectos de los fármacos , Receptores de Serotonina/metabolismo , Antagonistas de la Serotonina/farmacología , Serotonina/farmacología , Animales , Lóbulo Frontal/metabolismo , Masculino , Neuralgia/metabolismo , Dimensión del Dolor , Ratas , Ratas Sprague-Dawley
7.
Neuroscience ; 220: 322-9, 2012 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-22617702

RESUMEN

Recent study from our laboratory has indicated that microinjection of glutamate into the nucleus tractus solitarius (NTS) facilitates the cardiac-somatic reflex induced by pericardial capsaicin. Further, N-methyl-d-aspartate (NMDA) receptors and metabotropic glutamate receptors (mGluRs) mediate this function. However, the roles of the individual receptor subtypes or subunits in modulating cardiac nociception are unknown. Among the three groups of mGluRs, group III mGluRs are the primary mGluR subtype expressed in visceral afferent neurons in the NTS. The present study examined the roles of group III mGluRs and their subtype 7 and 8 receptors (mGluR7 and mGluR8) in modulating the cardiac-somatic reflex induced by pericardial capsaicin, which was monitored by recording electromyogram (EMG) activity from the spinotrapezius muscle in anesthetized rats. Intra-NTS microinjection of a group III mGluR agonist, l-(+)-2-Amino-4-phosphonobutyric acid (l-AP4, at 1, 10, and 20 nmol) or a selective mGluR7 agonist, N,N'-diphenylmethyl-1,2-ethanediamine dihydrochloride (AMN082, at 1, 2, and 4 nmol) both decreased the EMG response in a dose-dependent manner. This decrease was inhibited by the group III mGluR antagonist (RS)-α-Methylserine-O-phosphate (MSOP, at 20 nmol). In contrast, intra-NTS microinjection of a selective mGluR8 agonist, (S)-3, 4-dicarboxyphenylglycine (DCPG, at 6 and 8 nmol), significantly increased the EMG response above control levels. This effect was eliminated by intra-NTS MSOP and by vagal deafferentation. These data suggest that group III mGluRs and mGluR7 in the NTS display an inhibitory effect, while mGluR8 displays a facilitatory effect in modulating cardiac nociception, and this facilitatory effect is dependent on vagal afferents.


Asunto(s)
Corazón/inervación , Nocicepción/fisiología , Dolor Referido/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Núcleo Solitario/metabolismo , Vías Aferentes/fisiología , Animales , Masculino , Ratas , Ratas Sprague-Dawley , Tórax , Nervio Vago/fisiología
8.
Neuroscience ; 207: 326-32, 2012 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-22326452

RESUMEN

Many patients suffer from secondary muscle hyperalgesia after experiencing angina pectoris. In this study, we examined the role of the nucleus tractus solitarius (NTS) and glutamate receptors in modulating cardiac-evoked muscle hyperalgesia induced by pericardial capsaicin, which was monitored by recording electromyogram (EMG) activity from the spinotrapezius muscle in the anesthetized rat. Unilateral chemical lesioning of the commissural NTS with the neurotoxin ibotenic acid significantly depressed the cardiac-somatic reflex; the EMG responses decreased to 56.4 ± 6.9% of that of the controls (5 of 5). Microinjection of the excitatory amino acid glutamate, at 10, 20, and 50 nmol, into the commissural NTS increased the EMG response, in a dose-dependent manner, to 116.9 ± 4.9%, 143.9 ± 10.2%, and 214.2 ± 15.8% (n=8), respectively, of that of the controls. In contrast, microinjection of the N-methyl-D-aspartate (NMDA) receptor antagonist (+)-5-methyl-10, 11-dihydro-5H-dibenzo [a, d]-cyclohepten-5,10-imine maleate (MK-801) at 4 and 6 nmol, decreased the EMG response to 45.2 ± 10.6% and 36.8 ± 14.3%, respectively, of that of the controls (n=8 for each dose). Similarly, the metabotropic glutamate receptor (mGluR) antagonist (RS)-a-methyl-4-carboxyphenylglycine (MCPG), at 2.5 and 5 nmol, decreased the EMG response to 65.2 ± 16.3% and 57.0 ± 4.2%, respectively, of that of the controls. When a combination of MK-801 and MCPG was administrated, the EMG response further decreased to 22.5 ± 13.2% (n=6) of that of the controls. However, administration of a non-NMDA receptor antagonist 6, 7-dinitroquinoxaline-2, 3-dione (DNQX), at 2 and 5 nmol, had no effect on the EMG response. These results suggest that the NTS is involved in the facilitation of the cardiac-somatic reflex, and that the NMDA receptor and mGluRs play an important role in mediating this effect.


Asunto(s)
Fenómenos Fisiológicos Cardiovasculares , Ácido Glutámico/fisiología , Hiperalgesia/fisiopatología , Receptores de Glutamato/fisiología , Reflejo/fisiología , Núcleo Solitario/fisiología , Animales , Desnervación/métodos , Ácido Glutámico/toxicidad , Hiperalgesia/inducido químicamente , Masculino , Microinyecciones/métodos , Neurotoxinas/toxicidad , Ratas , Ratas Sprague-Dawley , Núcleo Solitario/efectos de los fármacos
9.
Neuroscience ; 185: 174-82, 2011 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-21521650

RESUMEN

The purpose of the present study was to examine whether the rostroventral portion of the medulla oblongata (RVM) exerts descending modulation on the cardiosomatic motor reflex (CMR) in rats. Capsaicin (1 µg/ml, 0.2 ml) was injected into the pericardial sac as an algesic substance to induce the CMR, which was monitored via electromyogram (EMG) responses of dorsal spinotrapezius muscle to the noxious cardiac stimulus. Descending modulation of the CMR was observed by electrical or chemical stimulation of RVM. Specifically, electrical stimulation of RVM produced facilitatory, inhibitory or biphasic effects on the CMR evoked by noxious cardiac stimulation, depending on stimulation intensity. In addition, glutamate receptor activation in RVM replicated the effects of electrical stimulation. Lidocaine interruption of the ventrolateral funiculus/ventral funiculus (VLF/VF) or transection of the dorsolateral funiculus (DLF) revealed that the descending facilitatory and inhibitory influences from RVM were conveyed via the VLF/VF and DLF, respectively. Furthermore, intrathecal administration of naloxone or yohimbine partly reversed the inhibitory effect of RVM electrical stimulation, suggesting that opioid and noradrenergic systems are involved in descending RVM modulation of the CMR.


Asunto(s)
Potenciales Evocados Motores/fisiología , Bulbo Raquídeo/fisiología , Reflejo/fisiología , Antagonistas de Receptores Adrenérgicos alfa 2/farmacología , Anestésicos Locales/farmacología , Animales , Capsaicina/farmacología , Relación Dosis-Respuesta a Droga , Estimulación Eléctrica/métodos , Electromiografía , Potenciales Evocados Motores/efectos de los fármacos , Lateralidad Funcional/efectos de los fármacos , Lidocaína/farmacología , Masculino , Bulbo Raquídeo/efectos de los fármacos , Naloxona/farmacología , Antagonistas de Narcóticos/farmacología , Vías Nerviosas/efectos de los fármacos , Vías Nerviosas/fisiología , Ratas , Ratas Sprague-Dawley , Reflejo/efectos de los fármacos , Fármacos del Sistema Sensorial/farmacología , Traumatismos de la Médula Espinal/patología , Yohimbina/farmacología
10.
Clin Nucl Med ; 23(1): 29-32, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9442962

RESUMEN

PURPOSE: Differentiation of recurrent nasopharyngeal carcinoma (NPC) from radiation fibrosis using conventional diagnostic methods can be difficult. The authors prospectively studied patients with NPC to determine the efficacy of Tc-99m MIBI scintigraphy in detecting the primary, residual, and recurrent tumors. MATERIALS AND METHODS: The authors performed Tc-99m MIBI SPECT studies of the head and neck and whole-body scans on 21 healthy adult volunteers and 43 patients with NPC before (n = 26) or after (n = 17) radiotherapy. The images were qualitatively assessed by comparing the nasopharyngeal uptake to scalp radioactivity. MIBI uptake index was calculated as a ratio of mean counts per pixel in the normal nasopharynx or tumor to mean counts per pixel in the scalp. RESULTS: There was significantly higher uptake of Tc-99m MIBI by NPC than normal nasopharynx and radiation fibrosis (P < .05). The authors determined the optimum cutoff MIBI uptake index value of 1.3 with a sensitivity of 97%, a specificity of 100%, a positive predictive value of 100%, a negative predictive value of 96%, and an accuracy of 98% for diagnosing NPC. CONCLUSION: This study suggests that Tc-99m MIBI SPECT is useful for detecting primary NPC and for differentiating residual or recurrent tumor from radiation fibrosis. The authors propose the cutoff MIBI uptake index value of 1.3 for diagnosing NPC.


Asunto(s)
Carcinoma/diagnóstico por imagen , Neoplasias Nasofaríngeas/diagnóstico por imagen , Radiofármacos , Tecnecio Tc 99m Sestamibi , Tomografía Computarizada de Emisión de Fotón Único , Adulto , Anciano , Carcinoma/radioterapia , Diagnóstico Diferencial , Femenino , Fibrosis , Cabeza/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/radioterapia , Nasofaringe/diagnóstico por imagen , Nasofaringe/patología , Nasofaringe/efectos de la radiación , Cuello/diagnóstico por imagen , Invasividad Neoplásica/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Neoplasia Residual/diagnóstico por imagen , Valor Predictivo de las Pruebas , Estudios Prospectivos , Traumatismos por Radiación/diagnóstico por imagen , Cuero Cabelludo/diagnóstico por imagen , Sensibilidad y Especificidad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...