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1.
Zhonghua Yi Xue Za Zhi ; 102(22): 1660-1665, 2022 Jun 14.
Artículo en Chino | MEDLINE | ID: mdl-35692018

RESUMEN

Objectives: To investigate the feasibility of using a porcine fibrin sealant to wrap and remove kidney calculi fragments through an isolated porcine kidney model. Methods: In the isolated porcine kidney stone model (implanted with 100 mg, air dried, ≤1 mm human stone fragments, n=6;implanted with 100 mg, air dried, ≤3 mm human stone fragments, n=6), the ureteral soft mirror combined with the 12/14Fr UAS was used to test the effect of stone extraction using only two stone extraction methods: basket extraction (control group, ≤1 mm stone fragments, n=3; ≤3 mm stone fragments, n=3) and basket-sealant extraction (test group, ≤1 mm stone fragments, n=3; ≤3 mm stone fragments, n=3). Compare the stone removal rate and operation time of the two stone retrieval methods. The sealant was put into urine of normal human and observed. Results: Porcine Fibrin Sealant can form a gel in saline and urine and adhere and wrap stone fragments. The time of procedures of test (basket-sealant) and control (basket) group in kidneys implanted with ≤ 1 mm stone fragments were (14.0±4.2) and (29.0±0.7)min (P<0.05) stone clearance rates were (90.9±1.4)% and (48.4±15.7)% (P<0.05), respectively. In kidneys implanted with ≤ 3 mm fragments, time of procedures were (12.8±4.0) and (30.0±0)min (P<0.05) Stone clearance rates were (91.1±5.0)% and (20.7±8.0)% (P<0.05). The Sealant dissolves by itself in normal human urine and normal saline at 37 ℃ for 24 hours. Conclusion: The appropriate concentration of Porcine Fibrin Sealant assisted stone retrieval may become a new method for removing small stone fragments in retrograde intrarenal surgery.


Asunto(s)
Cálculos Renales , Litotricia , Cálculos Ureterales , Animales , Adhesivo de Tejido de Fibrina , Riñón , Cálculos Renales/cirugía , Porcinos , Cálculos Ureterales/terapia , Ureteroscopía/métodos
2.
Fa Yi Xue Za Zhi ; 37(4): 546-554, 2021 Aug.
Artículo en Chino | MEDLINE | ID: mdl-34726010

RESUMEN

ABSTRACT: In the field of forensic medicine, diagnosis of sudden cardiac death is limited by subjective factors and manual measurement methods, so some parameters may have estimation deviation or measurement deviation. As postmortem CT imaging plays a more and more important role in the appraisal of cause of death and cardiopathology research, the application of deep learning such as artificial intelligence technology to analyze vast amounts of cardiac imaging data has provided a possibility for forensic identification and scientific research workers to conduct precise diagnosis and quantitative analysis of cardiac diseases. This article summarizes the main researches on deep learning in the field of cardiac imaging in recent years, and proposes a feasible development direction for the application of deep learning in the virtual anatomy of sudden cardiac death at present.


Asunto(s)
Inteligencia Artificial , Aprendizaje Profundo , Autopsia , Muerte Súbita Cardíaca/etiología , Medicina Legal , Humanos
4.
Int J Oral Maxillofac Surg ; 45(10): 1293-8, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26972159

RESUMEN

The aim of this study was to investigate the incidence of bleeding after dental extraction without stopping antiplatelet therapy. Postoperative bleeding was assessed in a total of 1271 patients who were divided into two groups: a study group comprising 183 patients on antiplatelet therapy (aspirin 125 patients/185 occasions; clopidogrel 42 patients/65 occasions; dual therapy 16 patients/24 occasions) who underwent 548 dental extractions on 274 occasions, and a control group comprising 1088 patients who were not receiving any antiplatelet or anticoagulant therapy and underwent 2487 dental extractions on 1472 occasions. The incidence of postoperative bleeding was higher in the study group (5/274, 1.8%) than in the control group (10/1472, 0.7%), and also in the dual antiplatelet subgroup (1/24, 4.2%) than in the single antiplatelet subgroups (clopidogrel: 2/65, 3.1%; aspirin: 2/185, 1.1%); however, these differences were not significant. Postoperative bleeding was managed successfully by repacking with Gelfoam impregnated with tranexamic acid powder in 12 patients and by resuturing in three of the control patients undergoing extraction of impacted teeth with flap elevation. These findings indicate that there is no need to interrupt antiplatelet drugs before dental extraction.


Asunto(s)
Aspirina/administración & dosificación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Hemorragia Posoperatoria/epidemiología , Ticlopidina/administración & dosificación , Extracción Dental/métodos , Adulto , Anciano , Anciano de 80 o más Años , Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hemorragia Posoperatoria/terapia , Estudios Retrospectivos , Extracción Dental/efectos adversos , Extracción Dental/estadística & datos numéricos , Adulto Joven
5.
Nanotechnology ; 27(7): 075601, 2016 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-26762929

RESUMEN

Low-temperature scanning gate microscopy (LT-SGM) studies of graphene allow one to obtain important spatial information regarding coherent transport such as weak localization (WL) and universal conductance fluctuations. Although fascinating LT-SGM results on pristine graphene prepared by mechanical exfoliation have been reported in the literature, there appears to be a dearth of LT-SGM results on chemical vapor deposition (CVD)-grown graphene whose large scale and flexible substrate transferability make it an ideal candidate for coherent electronic applications. To this end, we have performed LT-SGM studies on CVD-grown graphene wide constriction (0.8 µm), which can be readily prepared by cost-effective optical lithography fully compatible with those in wafer foundry, in the WL regime. We find that the movable local gate can sensitively modulate the total conductance of the CVD graphene constriction possibly due to the intrinsic grain boundaries and merged domains, a great advantage for applications in coherent electronics. Moreover, such a conductance modulation by LT-SGM provides an additional, approximately magnetic-field-independent probe for studying coherent transport such as WL in graphene and spatial conductance variation.

6.
Transplant Proc ; 46(3): 666-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24767318

RESUMEN

OBJECTIVE: Hepatic steatosis can cause substantial problems for both donors and recipients in living donor liver transplantation (LDLT). The aim of this study is to evaluate the accuracy of the magnetic resonance IDEAL (iterative decomposition of water and fat with echo asymmetry and least squares estimation) sequence in quantifying the liver fat during LDLT. MATERIALS AND METHODS: A total of 63 liver donors (29 men and 34 women ranging from 18 to 47 years old with a mean age of 30) who received both magnetic resonance imaging (MRI) and intraoperative liver biopsy were enrolled in this study. MR IDEAL IQ sequences were performed by 1.5-T MRI (Discovery 450; GE Healthcare, Milwaukee, Wis, United States) to estimate the liver fatty content. Accuracy was assessed through linear regression between fat fraction image and pathology grading. Sensitivity and specificity of MR IDEAL IQ fat fractions were also calculated. RESULTS: A total of 63 LDLTs were performed and with pathology grading. No fatty content was found in 48 donors (76.2%; group 1), 5% to 10% fatty liver in 11 donors (17.4%; group 2), 11% to 15% fatty liver in 2 donors (3.2%; group 3), and >16% fatty change in 2 donors (3.2%; group 4). MR IDEAL fat fraction results were excellent in prediction of the normal and fatty content and with good correlation with the pathology grading (2.9 ± 0.9, 8.3 ± 4.2, P < .0001). Linear regression between IDEAL image and pathology grading indicated a high accuracy rate (R(2) = 0.813, R(2) = 0.9286) for all 4 groups. The sensitivity and specificity for detection of liver steatosis in MRI fat fraction image were 100% and 77.1% (P < .0001, 95% confidence interval 0.000-1.000). CONCLUSION: MR IDEAL IQ sequencing is a highly precise and accurate method in quantifying hepatic steatosis for the living donor.


Asunto(s)
Tejido Adiposo/patología , Trasplante de Hígado , Hígado/patología , Donadores Vivos , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
7.
Genet Mol Res ; 11(4): 4707-10, 2012 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-23096907

RESUMEN

We isolated and characterizated 12 polymorphic microsatellite loci in the rapid racerunner Eremias velox (Squamata: Lacertidae). The loci were screened in 37 E. velox individuals. The number of alleles ranged from 6 to 16. The observed heterozygosity ranged from 0.432 to 0.919, and the expected heterozygosity ranged from 0.685 to 0.902. These microsatellite markers should prove useful for population genetic studies of E. velox and other Eremias species.


Asunto(s)
Repeticiones de Microsatélite , Polimorfismo Genético , Alelos , Animales , Secuencia de Bases , Conservación de los Recursos Naturales , Sitios Genéticos , Heterocigoto , Lagartos/genética , Análisis de Secuencia de ADN
8.
Clin Microbiol Infect ; 17(9): 1421-5, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21175956

RESUMEN

Although routine bacterial culture is the traditional reference standard method for the detection of Salmonella infection in children with diarrhoea, it is a time-consuming procedure that usually only gives results after 3-4 days. Some molecular detection methods can improve the turn-around time to within 24 h, but these methods are not applied directly from stool or rectal swab specimens as routine diagnostic methods for the detection of gastrointestinal pathogens. In this study, we tested the feasibility of a bacterial enrichment culture-based real-time PCR assay method for detecting and screening for diarrhoea in children caused by Salmonella. Our results showed that the minimum real-time PCR assay time required to detect enriched bacterial culture from a swab was 3 h. In all children with suspected Salmonella diarrhoea, the enrichment culture-based real-time PCR achieved 85.4% sensitivity and 98.1% specificity, as compared with the 53.7% sensitivity and 100% specificity of detection with the routine bacterial culture method. We suggest that rectal swab sampling followed by enrichment culture-based real-time PCR is suitable as a rapid method for detecting and screening for Salmonella in paediatric patients.


Asunto(s)
Enterocolitis/microbiología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Recto/microbiología , Intoxicación Alimentaria por Salmonella/microbiología , Salmonella/genética , Salmonella/aislamiento & purificación , Técnicas de Cultivo de Célula , Niño , Estudios de Cohortes , Diarrea/microbiología , Humanos , Intoxicación Alimentaria por Salmonella/diagnóstico , Sensibilidad y Especificidad
9.
Int J Cosmet Sci ; 32(4): 258-65, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20412334

RESUMEN

SYNOPSIS: In this study, we investigated the properties of three different liquid crystal-type humectants prepared through a simple emulsion process. Under a polarized microscope, we observed liquid crystal textures for each of the three moisturizers. When we applied them onto the hands and face, we found that they all provided effective hydration, with pheohydrane/liquid crystal moisturizer exhibiting superior performance. We also investigated the surface properties (contact angle, zeta potential, surface tension, transmission electron microscopy and scanning electron microscopy analyses) after adding pheohydrane to Formula product.


Asunto(s)
Emolientes/síntesis química , Cristales Líquidos/química , Emolientes/química , Humanos , Cristales Líquidos/ultraestructura , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Microscopía de Polarización , Propiedades de Superficie
10.
Cell Mol Neurobiol ; 30(3): 339-46, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19777342

RESUMEN

Gene transfer has been used to examine the role of putative neurotransmitters in the nucleus tractus solitarii (NTS). Most such studies used adenovirus vector-mediated gene transfer although adenovirus vector transfects both neuronal and non-neuronal cells. Successful transfection in the NTS has also been reported with lentivirus as the vector. Feline immunodeficiency virus (FIV), a lentivirus, may preferentially transfect neurons and could be a powerful tool to delineate physiological effects produced by altered synthesis of transmitters in neurons. However, it has not been studied in NTS. Therefore, we sought to determine whether FIV transfects rat NTS cells and to define the type of cell transfected. We found that injection of FIV encoding LacZ gene (FIVLacZ) into the NTS led to transfection of numerous NTS cells. Injection of FIVLacZ did not alter immunoreactivity (IR) for neuronal nitric oxide synthase, which we have shown resides in NTS neurons. A majority (91.7 +/- 3.9%) of transfected cells contained IR for neuronal nuclear antigen, a neuronal marker; 2.1 +/- 3.8% of transfected cells contained IR for glial fibrillary acidic protein, a glial marker. No transfected neurons or fibers were observed in the nodose ganglion, which sends afferents to the NTS. We conclude that FIV almost exclusively transfects neurons in the rat NTS from which it is not retrogradely transported. The cell-type specificity of FIV in the NTS may provide a molecular method to study local physiological functions mediated by potential neurotransmitters in the NTS.


Asunto(s)
Vectores Genéticos/genética , Virus de la Inmunodeficiencia Felina/genética , Neurotransmisores/biosíntesis , Núcleo Solitario/metabolismo , Transfección/métodos , Vías Aferentes/citología , Vías Aferentes/enzimología , Animales , Antígenos Nucleares/genética , Transporte Axonal/fisiología , Mapeo Encefálico/métodos , Genes Reporteros , Proteína Ácida Fibrilar de la Glía/genética , Masculino , Proteínas del Tejido Nervioso/genética , Técnicas de Trazados de Vías Neuroanatómicas/métodos , Neuronas/citología , Neuronas/enzimología , Neuronas/virología , Ganglio Nudoso/citología , Ganglio Nudoso/enzimología , Ratas , Ratas Sprague-Dawley , Núcleo Solitario/citología , Núcleo Solitario/enzimología , Coloración y Etiquetado/métodos , beta-Galactosidasa/genética
11.
Br J Radiol ; 82(984): e253-5, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19934067

RESUMEN

Ectopic pancreas is relatively uncommon and usually occurs in the stomach or duodenum. Retroperitoneal ectopic pancreas has not previously been documented. We report the case of a 48-year-old man with retroperitoneal ectopic pancreas that imitated bilateral adrenal tumours on ultrasound and MRI. Subsequent CT-guided biopsies confirmed an ectopic pancreas. The lesions remained stable during follow-up for 7 years. In retrospect, the similarity in signal intensities and enhancement pattern between the retroperitoneal masses and the pancreas may have been a clue to the diagnosis of this rare entity.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/diagnóstico , Coristoma/diagnóstico , Páncreas , Diagnóstico Diferencial , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Espacio Retroperitoneal , Tomografía Computarizada por Rayos X
12.
Clin Exp Rheumatol ; 27(6): 902-6, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20149303

RESUMEN

OBJECTIVES: To analyse the characteristic features of patients with coexistence of gouty arthritis and pyarthrosis at our university hospital in southern Taiwan, an area with high prevalence of hyperuricemia and gout. METHODS: A retrospective chart review was performed for patients who had concomitant gouty and septic arthritis from July 1998 to June 2008. Clinical and laboratory data of these patients were analysed. Furthermore, a comparison was made with published cases in English literature. RESULTS: Fourteen cases with coexistence of gouty arthritis and pyarthrosis have been identified during the past 10 years. There were 13 male and 1 female, all of Han Chinese in ethnicity, with ages ranging from 45 to 85 and an average of 63.7 years. At disease presentation, there were 11 oligoarticular cases (78.6%), 2 monoarticular cases (14.3%) and 1 polyarticular case (7.1%). Ankle and knee joints were most commonly involved. Bacteriological analyses demonstrated gram-positive cocci in 12 cases, of these 10 were oxacillin-sensitive Staphylococcus aureus (71.4%). Multiple tophi deposition was noted in 13 patients (92.9%) and among them 11 patients (84.6%) had associated chronic kidney disease. CONCLUSION: Different clinical presentations and bacteriological characteristics have been identified in the present series. While the mechanisms responsible for such a coexistence remain to be elucidated, these cases underline the importance of thorough evaluation of the aspirated synovial fluid. Our report adds a novel insight into the understanding of the clinical and microbiological manifestations of such a rare concurrence of gouty and septic arthritis.


Asunto(s)
Artritis Gotosa/complicaciones , Artritis Infecciosa/complicaciones , Anciano , Anciano de 80 o más Años , Artritis Gotosa/microbiología , Artritis Gotosa/cirugía , Artritis Infecciosa/microbiología , Artritis Infecciosa/cirugía , Desbridamiento , Femenino , Humanos , Articulaciones/microbiología , Masculino , Registros Médicos , Persona de Mediana Edad , Estudios Retrospectivos , Infecciones Estafilocócicas/complicaciones , Staphylococcus aureus
13.
Transplant Proc ; 40(8): 2460-2, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18929768

RESUMEN

Accurate pretransplant evaluation of a potential donor in living donor liver transplantation (LDLT) is essential in preventing postoperative liver failure and optimizing safety. The aim of this study was to investigate the reasons for exclusion from donation of potential donors in adult LDLT. From September 2003 to June 2006, 266 potential donors were evaluated for 215 recipients: 220 potential donors for 176 adult recipients; 46 for 39 pediatric recipients. Imaging modalities including Doppler ultrasound, computerized tomography (CT), and magnetic resonance (MR) angiography provided vascular evaluation and MR cholangiopancreatography to evaluate biliary anatomy. Calculation of liver volume and assessment of steatosis were performed by enhanced and nonenhanced CT, respectively. In the adult group, only 83 (37.7%) potential donors were considered suitable for LDLT. Of the 137 unsuitable potential donors, 36 (26.2%) candidates were canceled because of recipient issues that included death of 15 recipients (10.9%), main portal vein thrombosis (8%), recipient condition beyond surgery (5%), and no indication for liver transplantation due to disease improvement (2%). The remaining 101 (73.8%) candidates who were excluded included steatosis (27.7%), an inadequate remnant volume (57.4%), small-for-size graft (8.9%), HLA-homozygous donor leading to one-way donor-recipient HLA match (3%), psychosocial problems (4%), as well as variations of hepatic artery (4%), portal vein (1%), and biliary system anatomy (5%). Anatomic considerations were not the main reason for exclusion of potential donors. An inadequate remnant liver volume (< 30%) is the crucial point for the adult LDLT decision.


Asunto(s)
Trasplante de Hígado/métodos , Donadores Vivos , Cuidados Preoperatorios , Adulto , Arteria Hepática/diagnóstico por imagen , Humanos , Hígado/anatomía & histología , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética , Selección de Paciente , Complicaciones Posoperatorias/prevención & control , Tomografía Computarizada por Rayos X , Ultrasonografía Doppler
15.
Neuroscience ; 154(2): 690-700, 2008 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-18479828

RESUMEN

Substance P (SP) and glutamate are implicated in cardiovascular regulation by the nucleus tractus solitarii (NTS). Our earlier studies suggest that SP, which acts at neurokinin 1 (NK1) receptors, is not a baroreflex transmitter while glutamate is. On the other hand, our recent studies showed that loss of NTS neurons expressing NK1 receptors leads to loss of baroreflex responses and increased blood pressure lability. Furthermore, studies have suggested that SP may interact with glutamate in the NTS. In this study, we sought to test the hypothesis that NK1 receptors colocalize with glutamate receptors, either N-methyl-d-aspartate (NMDA) receptors or AMPA receptors or both in the NTS. We performed double-label immunofluorescent staining for NK1 receptors and either N-methyl-d-aspartate receptor subunit 1 (NMDAR1) or AMPA specific glutamate receptor subunit 2 (GluR2) in the rat NTS. Because vesicular glutamate transporter 2 (VGLUT2) containing fibers are prominent in portions of the NTS where cardiovascular afferent fibers terminate, we also performed double-label immunofluorescent staining for NK1 receptors and VGLUT2. Confocal microscopic images showed that NK1 receptors-immunoreactivity (IR) and NMDAR1-IR colocalized in the same neurons in many NTS subnuclei. Almost all NTS neurons positive for NK1 receptor-IR also contained NMDAR1-IR, but only 53.4% to 74.8% of NMDAR1-IR positive neurons contained NK1 receptors-IR. NK1 receptor-IR and GluR2-IR also colocalized in many neurons in NTS subnuclei. A majority of NK1 receptor-IR positive NTS neurons also contained GluR2-IR, but only 45.8% to 73.9% of GluR2-IR positive NTS neurons contained NK1 receptors-IR. Our results also showed that fibers labeled for VGLUT2-IR were in close apposition to fibers and neurons labeled for NK1 receptor-IR. The data support our hypothesis, provide an anatomical framework for glutamate and SP interactions, and may explain the loss of baroreflexes when NTS neurons, which could respond to glutamate as well as SP, are killed.


Asunto(s)
Neuronas/metabolismo , Receptores AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de Neuroquinina-1/metabolismo , Núcleo Solitario/metabolismo , Animales , Técnica del Anticuerpo Fluorescente Indirecta , Masculino , Microscopía Confocal , Neuronas/ultraestructura , Ratas , Ratas Sprague-Dawley , Receptores AMPA/biosíntesis , Receptores AMPA/genética , Receptores de N-Metil-D-Aspartato/biosíntesis , Receptores de N-Metil-D-Aspartato/genética , Núcleo Solitario/citología , Núcleo Solitario/ultraestructura , Proteína 2 de Transporte Vesicular de Glutamato/biosíntesis , Proteína 2 de Transporte Vesicular de Glutamato/genética
16.
Lupus ; 17(1): 34-9, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18089681

RESUMEN

CD4+CD25+bright T cells played a crucial role in the suppression of immune response. Recently, decreased levels of CD4+CD25+bright T cells in the peripheral blood of patients with systemic lupus erythematosus were reported, suggesting the potential role of CD4+CD25+bright T cells in human autoimmune diseases. Primary Sjögren's syndrome (pSS) is another common human systemic autoimmune disease. The present study aimed to investigate the levels of CD4+CD25+bright T cells in pSS and to correlate their levels with some biomarkers of inflammation and immune activation. Thirty-three patients with pSS and 35 age- and sex-matched normal individuals were enrolled in the study. The flowcytometric method was applied in the measurement of CD4+CD25+bright T cells. The results showed that patients with pSS had statistically lower levels of CD4+CD25+bright T cells than normal controls, expressed either as absolute cell numbers (mean+/-SD: 47.07+/-25.53 cells/mm3 versus 79.55+/-34.56 cells/mm3, P<0.001) or as percentages of peripheral blood mononuclear cells (mean+/-SD: 2.79+/-1.06% versus 3.84+/-1.42%, P<0.001) or as percentages of CD4+ T cells (mean+/-SD: 7.85+/-2.62% versus 11.68+/-3.78%, P<0.005). Moreover, there were statistically significant inverse correlations between the levels of CD4+CD25+bright T cells and some parameters of inflammation or immune activation including erythrocyte sedimentation rate, C-reactive protein, IgG and rheumatoid factors. The result suggested that CD4+CD25+bright T cells were likely to play anti-inflammatory and immunosuppressive roles in the pathogenesis of pSS. However, the exact functions of decreased circulating CD4+CD25+bright T cells in pSS need further elucidated.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Inflamación/inmunología , Subunidad alfa del Receptor de Interleucina-2/análisis , Síndrome de Sjögren/inmunología , Linfocitos T Reguladores/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Sedimentación Sanguínea , Proteína C-Reactiva/metabolismo , Estudios de Casos y Controles , Regulación hacia Abajo , Femenino , Citometría de Flujo , Humanos , Inmunoglobulina G/sangre , Inflamación/sangre , Masculino , Persona de Mediana Edad , Factor Reumatoide/sangre , Síndrome de Sjögren/sangre
17.
Brain Res ; 1171: 42-51, 2007 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-17761150

RESUMEN

Numerous studies have suggested that nitric oxide (NO) in the nucleus tractus solitarii (NTS) participates in modulating cardiovascular function. Nitric oxide synthase (NOS), the enzyme responsible for synthesis of NO, exists in 3 isoforms: endothelial NOS (eNOS), neuronal NOS (nNOS), and inducible NOS (iNOS). Although the distribution of nNOS in the NTS has been well documented, the distribution of eNOS in the NTS has not. Because recent studies have shown that eNOS may contribute to regulation of baroreceptor reflexes and arterial pressure, we examined the distribution of eNOS and the types of cells that express it in rat NTS by using multiple labels for immunofluorescent staining and confocal microscopy. Immunoreactivity (IR) for eNOS and nNOS was found in cells and processes in all NTS subnuclei, but eNOS-IR was more uniformly distributed than was nNOS-IR. Although structures containing either eNOS-IR or nNOS-IR were often present in close proximity, they never contained both isoforms. Almost all eNOS-IR positive structures, but no nNOS-IR positive structures, contained IR for the glial marker glial fibrillary acidic protein. Furthermore, while all nNOS-IR positive cells contained IR for the neuronal marker neuronal nuclear antigen (NeuN), none of the eNOS-IR positive cells contained NeuN-IR. We conclude that eNOS in the NTS is present only in astrocytes and endothelial cells, not in neurons. Our data complement previous physiological studies and suggest that although NO from nNOS may modulate neurotransmission directly in the NTS, NO from eNOS in the NTS may modulate cardiovascular function through an interaction between astrocytes and neurons.


Asunto(s)
Células Endoteliales/enzimología , Neuronas/enzimología , Óxido Nítrico Sintasa de Tipo III/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Núcleo Solitario/citología , Animales , Humanos , Microscopía Confocal , Óxido Nítrico Sintasa de Tipo II/metabolismo , Fosfopiruvato Hidratasa/metabolismo , Ratas , Ratas Sprague-Dawley , Núcleo Solitario/enzimología
18.
J Evol Biol ; 20(3): 1037-45, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17465914

RESUMEN

The maternal manipulation hypothesis for the evolution of reptilian viviparity has been claimed to apply to any situation where gravid females are able to maintain body temperatures different from those available in external nests, but empirical data that support this hypothesis are very limited. Here, we tested this hypothesis using gravid females of a warm-climate lizard, Mabuya multifasciata, by subjecting them to five thermal regimes for the whole gestation period. We found gravid females selected lower body temperatures and thermoregulated more precisely than did nongravid females. Offspring produced in different treatments differed in head size, limb length and sprint speed, but not in overall body size or mass. Variation in morphological traits of offspring was induced primarily by extreme temperatures. Sprint speed of offspring was more likely affected by the mean but not by the variance of gestation temperatures. Gravid females maintained more stable body temperatures than did nongravid females not because these temperatures resulted in the optimization of offspring phenotypes but because the range of temperatures optimal for embryonic development was relatively narrow. Our data conform to the main predictions from the maternal manipulation hypothesis that females should adjust thermoregulation during pregnancy to provide optimal thermal conditions for developing embryos and that phenotypic traits forged by maternal thermoregulation should enhance offspring fitness.


Asunto(s)
Evolución Biológica , Regulación de la Temperatura Corporal , Lagartos/fisiología , Clima Tropical , Viviparidad de Animales no Mamíferos/fisiología , Animales , Femenino , Lagartos/anatomía & histología , Actividad Motora
19.
Astrobiology ; 7(6): 971-86, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18163873

RESUMEN

Dissolved H(2) concentrations up to the mM range and H(2) levels up to 9-58% by volume in the free gas phase are reported for groundwaters at sites in the Precambrian shields of Canada and Finland. Along with previously reported dissolved H(2) concentrations up to 7.4 mM for groundwaters from the Witwatersrand Basin, South Africa, these findings indicate that deep Precambrian Shield fracture waters contain some of the highest levels of dissolved H(2) ever reported and represent a potentially important energy-rich environment for subsurface microbial life. The delta (2)H isotope signatures of H(2) gas from Canada, Finland, and South Africa are consistent with a range of H(2)-producing water-rock reactions, depending on the geologic setting, which include both serpentinization and radiolysis. In Canada and Finland, several of the sites are in Archean greenstone belts characterized by ultramafic rocks that have under-gone serpentinization and may be ancient analogues for serpentinite-hosted gases recently reported at the Lost City Hydrothermal Field and other hydrothermal seafloor deposits. The hydrogeologically isolated nature of these fracture-controlled groundwater systems provides a mechanism whereby the products of water-rock interaction accumulate over geologic timescales, which produces correlations between high H(2) levels, abiogenic hydrocarbon signatures, and the high salinities and highly altered delta (18)O and delta (2)H values of these groundwaters. A conceptual model is presented that demonstrates how periodic opening of fractures and resultant mixing control the distribution and supply of H(2) and support a microbial community of H(2)-utilizing sulfate reducers and methanogens.


Asunto(s)
Planeta Tierra , Fuentes Generadoras de Energía , Exobiología , Geología , Hidrógeno/química , Marte , Origen de la Vida , Agua Dulce , Fenómenos Geológicos , Microbiología del Agua , Movimientos del Agua
20.
Eur J Drug Metab Pharmacokinet ; 31(2): 103-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16898078

RESUMEN

The phase II metabolite of acetaminophen in filamentous fungi and actinomycetes separated from soil was investigated. Fifty-four filamentous fungi and twenty-seven actinomycetes were screened to transform acetaminophen. The metabolites of acetaminophen were assayed using liquid chromatography-tandem mass spectrometry. The only metabolite was subject to enzymatic hydrolysis to confirm its structure. Acetaminophen was converted into glucoside conjugate, by filamentous fungi JX1-60, LN17-2, LN20-1 and the yield of the conjugate was 60.01%, 44.27%, 100%, respectively, and no phase I metabolites were detected. Glucoside conjugation of acetaminophen in filamentous fungi differs from the phase II metabolism of glucuronidation in humans. The fungus LN20-1 could be a suitable model to synthesize glucoside conjugate of acetaminophen.


Asunto(s)
Acetaminofén/metabolismo , Hongos/metabolismo , Glucósidos/metabolismo , Fase II de la Desintoxicación Metabólica , Microbiología del Suelo , Acetaminofén/química , Actinobacteria/metabolismo , Analgésicos no Narcóticos , China , Cromatografía Liquida , Glucósidos/química , Hidrólisis , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray
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