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Chronic kidney disease (CKD) is a major public health problem worldwide. When CKD patients progress to the stage of kidney failure, kidney replacement therapy (KRT) or conservative treatment (palliative or non-dialysis treatment) will be needed. The risk prediction models of chronic kidney failure have been developed in recent years. These models, focusing on demographic indicators, clinical indicators, and laboratory data, are used to predict the likelihood of progression to kidney failure and requiring KRT. This article will retrieve prediction models for chronic kidney failure as an outcome, demonstrate the current research progress, and hope that it may be helpful for the strategies of preventing chronic kidney failure.
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Fallo Renal Crónico , Humanos , Fallo Renal Crónico/terapia , Factores de Riesgo , Medición de Riesgo , Progresión de la EnfermedadRESUMEN
Objective: To explore the application value of personalized three-dimensional (3D) printed protective cap in brain protection after decompressive craniectomy (DC). Methods: Fourty-five patients who underwent DC from January 2021 to October 2021 were selected, including 26 males and 19 females, aged 5-73 (50±13) years old. The brain CT data were imported into 3D Slicer software to rebuild the protective cap through 3D printing. The cap was worn on the head of the patient, thereby preventing secondary braindamage. The follow-up results were compared with 53 patients without protective capduring the same period. Results: There were no statistically significant differences in age, skull defect location and follow-up time between the two groups (all P>0.05).Among 45 patients, 47 brain protective caps (2 cases with bilateral skull defects) were successfully designed. The time for image post-processingand 3D printing was (21.2±6.0) min and (62.4±8.3) min, respectively. There were 6 cases of low compliance, 9 cases of moderate compliance, 32 cases of high compliance, respectively. Six cases with low conformity were redesigned and printed, 2 of 9 cases with moderate conformity were redesigned and printed, and the remaining 7 cases reached high compliance after grinding and packaging. In the current study, 45 patients with brain protective caps were followed up for 3 months, and no secondary brain injury occurred. However, among 53 patients without brain protective caps during the same period, 4 patients had secondary accidental brain compression. The incidence of injury was 7.5 %, and the difference was statistically significant (P<0.001). Conclusion: Brain protective cap designed based on cranial CT and 3D printing can be used in patients with skull defects to protect the brain tissue from secondary crush damage and has certain clinical value.
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Lesiones Encefálicas , Neoplasias Encefálicas , Craniectomía Descompresiva , Adulto , Encéfalo , Craniectomía Descompresiva/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Impresión Tridimensional , Cráneo/cirugíaRESUMEN
Objective: To explore the feasibility of a method based on neuroimaging and surface markers for locating scalp projection of intracranial lesions. Methods: The clinical data of 46 patients who were used 'double-circle method' for locating scalp projection of intracranial lesions at Department of Neurosurgery,the First Affiliated Hospital of Xiamen University from January to June 2021 were retrospective analyzed. All patients with 2 electrodes(artificial fiducials) randomly attached to scalp had been examed thin-layer brain CT. The distances from the center of each fiducial to the root of the nose and tragus were measured through the images. A compass was used to draw two arcs with the root of nose and the tragus as the center and the pre-measured distance as the radius on patient's scalp. Then two arcs' intersection on the scalp was the fiducial. The method was named 'double-circle method'. Two neurosurgeons were arranged to perform fiducial identification with double-circle method, and record the error between the result and the actual fiducial point.Independent sample t test was used for data comparison, and Kappa test was used to analysis the inter-group consistency. Results: Ninety-two fiducial points of 46 patients were collected. Time consuming of doctor A was (8.1±2.3) minutes(range:5 to 15 minutes)and doctor B was (8.9±3.5) minutes(range:4 to 17 minutes).The positioning error from the doctor A was (4.4±2.4)mm(range:0 to 12 mm) and doctor B was(4.2±2.6) mm(range:0 to 14 mm)(t=-0.575,P=0.567),the difference was not statistically significant. The Kappa value of the consistency test of error between two doctors was 0.517(P=0.001).The consistency was moderate.Eight patients used 'double-circle method' and neuronavigation for locating scalp projection of intracranial lesions at the same time. The diameter of the lesions was (3.8±0.9)cm (range: 2.6 to 5.1 cm), and the positioning error of the 'double-circle method' and navigation was (4.0±1.9) mm(range: 1 to 6 mm), and all patients were confirmed to be accurately located during surgery. Conclusion: 'Double-circle method' is a simple,convenient and accurate way in locating intracranial lesions and has certain clinical significance.
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Neuronavegación , Cuero Cabelludo , Humanos , Neuroimagen , Neuronavegación/métodos , Estudios Retrospectivos , Cuero Cabelludo/diagnóstico por imagenRESUMEN
Objective: To observe the effects of recombinant adenovirus with human thioredoxin (hTRX) on the inflammatory response in mice with viral myocarditis and explore the related mechanism. Methods: Sixty Balb/c male mice were randomly divided into control group, myocarditis group, and hTRX group according to the random number table (n=20 each group). The myocarditis group and hTRX group were injected with 100 TCID(50) Coxackie virus B3 (0.1 ml) in the abdomen and control group were injected with saline. Two days before the viral injection, the hTRX group were injected with recombinant adenovirus vector coding the human thioredoxin gene by pericardial puncture and the control group and myocarditis group were injected with recombinant adenovirus vector without coding gene by pericardial puncture, all these mice were killed and hearts were removed 7 days later. The morphology of myocardial tissue in each group was detected by HE staining and the ultrastructure changes by electron microscope. The protein expressions of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and NF-κB were detected by ELISA and Western blot. Immunohistochemical staining was performed to observe the protein expression levels of thioredoxin. Results: Necrosis of myocardial cells and a small amount of cell infiltration were found in the myocarditis group and necrosis and cell infiltration were significantly reduced in the hTRX group and no myocardial lesion was found in control group on HE stained sections. Electron microscope examination evidenced cell swelling and dissolved myofilament, vacuoles degeneration in mitochondria in the myocarditis group. These changes were significantly reduced in the hTRX group. There was no myocardial lesion in control group. The protein expression of TNF-α, IL-1ß and NF-κB were significantly upregulated in myocarditis group than in control group (all P<0.01). The protein expression of TNF-α, IL-1ß and NF-κB were significantly downregulated in hTRX group than in myocarditis group (all P<0.01). Immunohistochemical staining showed that protein expression of hTRX was higher in hTRX group than in myocarditis group (P<0.01). Conclusion: Recombinant adenovirus hTRX can attenuate cardiac injury in mice with acute myocarditis via inhibiting the inflammatory response and downregulating the expression of TNF-α, IL-1ß and NF-κB.
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Inflamación , Miocarditis , Tiorredoxinas , Adenoviridae , Animales , Humanos , Inflamación/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Miocarditis/tratamiento farmacológico , Miocarditis/inmunología , Miocardio , Distribución Aleatoria , Tiorredoxinas/genética , Tiorredoxinas/fisiología , Factor de Necrosis Tumoral alfaRESUMEN
Keshan disease (KD) is an endemic cardiomyopathy associated with selenium deficiency. Recent studies indicate that glutathione peroxidase 1 (GPx1) mutation decreases GPx activity in myocardial cells and increases the risk of KD. To further clarify the correlation between GPx1 polymorphism and KD, we analyzed GPx1 polymorphism, blood selenium levels and GPx activity in KD patients and healthy controls in Heilongjiang Province. Four and 24 new mutation loci in the promoter and the exon region, respectively, of the GPx1 gene were found in the subjects, in contrast with the previously reported loci. There were no significant differences in the mutation frequency of these loci between the KD group and controls (chi-square test; P > 0.05). However, the mutation frequency of exon 474 was higher in the KD group (7/36) than in controls (2/41), and GPx activity was lower in the mutation group (90.475 ± 23.757 U/L) than in the non-mutation group (93.947 ± 17.463 U/L). Further investigation is necessary to clarify a possible causality between GPx1 exon 474 mutation and KD.
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Cardiomiopatías/genética , Infecciones por Enterovirus/genética , Glutatión Peroxidasa/genética , Miocitos Cardíacos/enzimología , Polimorfismo Genético , Selenio/deficiencia , Cardiomiopatías/sangre , Cardiomiopatías/enzimología , Estudios de Casos y Controles , China , Infecciones por Enterovirus/sangre , Infecciones por Enterovirus/enzimología , Exones , Femenino , Estudios de Asociación Genética , Genotipo , Glutatión Peroxidasa/metabolismo , Humanos , Masculino , Tasa de Mutación , Miocitos Cardíacos/patología , Regiones Promotoras Genéticas , Selenio/sangre , Glutatión Peroxidasa GPX1RESUMEN
Two-photon fluorescence microscopy and confocal reflectance microscopy were compared to detect intracellular gold nanorods in rat basophilic leukaemia cells. The two-photon photoluminescence images of gold nanorods were acquired by an 800 nm fs laser with the power of milliwatts. The advantages of the obtained two-photon photoluminescence images are high spatial resolution and reduced background. However, a remarkable photothermal effect on cells was seen after 30 times continuous scanning of the femto-second laser, potentially affecting the subcellular localization pattern of the nanorods. In the case of confocal reflectance microscopy the images of gold nanorods can be obtained with the power of light source as low as microwatts, thus avoiding the photothermal effect, but the resolution of such images is reduced. We have noted that confocal reflectance images of cellular gold nanorods achieved with 50 microW 800 nm fs have a relatively poor resolution, whereas the 50 microW 488 nm CW laser can acquire reasonably satisfactory 3D reflectance images with improved resolution because of its shorter wavelength. Therefore, confocal reflectance microscopy may also be a suitable means to image intracellular gold nanorods with the advantage of reduced photothermal effect.
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Basófilos/química , Citosol/química , Oro/análisis , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos , Nanotubos/análisis , Animales , Línea Celular Tumoral , RatasRESUMEN
In electric-field-responsive soft-matter systems, the suspended particles respond to the Lorentz local field (LLF), yielding abundant important phenomena. Even though the particles can easily rotate, the LLF was conventionally adopted as a quantity that is independent of rotations in the literature. In contrast, here we design an experiment to measure the LLF between two metallic spheres, one of which is rotating, and report a rotation-driven reduction. Excellent agreement between our experiment and theory reveals the role of the relaxation of dipole moments. Its relevance to biophysics, colloidal physics, and nonlinear physics is also discussed.
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Campos Electromagnéticos , Electrodos , Modelos Químicos , Niobio/química , Óxidos/química , Rotación , Aceites de Silicona/químicaRESUMEN
Many researches on polar-molecular electrorheological (PMER) fluids with giant electrorheological effects were reported in recent years. The particles of PMER fluids (PMER particles) are known to have a dielectric core with high dielectric constant and a shell of polar molecules. Our calculation of local electric fields using the finite element approach shows that the local electric field can cause an orientational polarization of the polar molecules. The saturation of the orientational polarization occurs on the outer shells of two nearby PMER particles. Then, it causes the strong outer shell-outer shell interaction between the two particles, and this kind of interaction is just responsible for the giant electrorheological effect. It is further realized that the PMER effect is mainly due to the interaction of the tail-head connected polar molecules within the two outer shells between the two PMER particles. Our theoretical results of static yield stresses are shown to be in excellent agreement with the reported experimental data by several groups. For general PMER fluids, the calculated static yield stress is nearly proportional to R(x-1). When h/R, the ratio between the thickness of shells and radius of PMER particles, changes from 0.05 to 0.5, the index x changes accordingly from 0.64 to 0.51. It is also found that particles with thinner thickness h and smaller radius R have larger electrorheological effects until the static yield stress shows a peak when R reaches about 10 nm.
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Objective:The aim of this study is to observe the effects of asthma and aspirin asthma on chronic rhinosinusitis and to explore the corresponding clinical value. Method: Eighty-six patients with CRS and asthma who were treated in the outpatient clinic during March 2015 to January 2018 were divided into asthma group(52 cases) and aspirin asthma group(34 cases) according to asthma and aspirin asthma. The clinical symptoms of the two groups were analyzed by symptomatic VAS score, Lund-Mackay score of sinus CT, and Lund-Kennedy score by nasal endoscopy.The scores of the two groups were compared under different lung function. Enzyme-linked immunosorbent assay the levels of inflammatory markers IL-5,IL-17,IFN-γ and TNF-α in the sinus secretions of the two groups were detected.Result:There were no significant differences in age, gender, smoking history, allergy history, surgical history and course of disease between the two groups(P<0.05), suggesting that the data were comparable. The sinus CT results showed that compared with the aspirin asthma group, the asthmatic group had irregular turbinates and a large turbinate,as shown in Figure 1. There were significant differences between the two groups in VAS score,Lund-Mackay score of sinus CT and Lund-Kennedy score by nasal endoscopy.The difference was statistically significant(P<0.05). And the forehead and/or facial pain or pain in the symptomatic VAS score(P<0.05), the Lund-Mackay score of the sinus CT(P<0.05),and intranasal.The difference in the Lund-Kennedy score(P<0.05) was statistically significant.There were significant differences in the distribution of lung function levels between the two groups of patients with mild airway obstructive respiratory dysfunction and pulmonary ventilation obstructive disorder(P<0.05).The average levels of IL-5,IL-17,IFN-γ and TNF-α in the aspirin asthma group were significantly lower than those in the asthma group(P<0.05).Conclusion:Aspirin-induced CRS produces asthma symptoms more severely than traditional asthma symptoms, but the induced local inflammatory response is relatively weak, and the mechanism may be closely related to IL-5,IL-17,IFN-γ and TNF-α levels.
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Aspirina/efectos adversos , Asma/inducido químicamente , Rinitis/fisiopatología , Sinusitis/fisiopatología , Enfermedad Crónica , Citocinas/análisis , Endoscopía , Humanos , InflamaciónRESUMEN
OBJECTIVE: The aim of this study was to examine the role of lncRNA-differentiation antagonizing non-protein coding RNA (DANCR) and its underlying mechanisms in chondrogenesis, more specifically in synovial fluid-derived mesenchymal stem cell (SFMSCs). MATERIALS AND METHODS: The expression levels of DANCR in SFMSCs were measured by qRT-PCR. Luciferase reporter assay and RIP assay were used to investigate the direct target of DANCR and miR-1275 in SFMSCs. The expression of matrix metallopeptidase 13 (MMP13, also known as chondrogenic marker) protein was examined by Western blot. Cell proliferation was analyzed by Cell Counting Kit-8 (CCK-8) assay, while chondrogenic differentiation was explored by sGAG assay. RESULTS: Our data indicated that DANCR can promote SFMSCs proliferation and chondrogenesis. In addition, miR-1275 was indicated as a direct target of DANCR. MiR-1275 was negatively regulated by DANCR via competing endogenous RNA (ceRNA) mechanism. Moreover, our data revealed that miR-1275 could bind to MMP13 and regulate its expression. CONCLUSIONS: Our findings suggested that DANCR was involved in SFMSCs proliferation and chondrogenesis. Mechanistically, DANCR functions as a sponge RNA for miR-1275 that regulates the expression of target gene MMP13. These data provide a therapeutic option for Osteoarthritis (OA).
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Condrogénesis/genética , Metaloproteinasa 13 de la Matriz/genética , MicroARNs/genética , Osteoartritis/genética , ARN Largo no Codificante/metabolismo , Diferenciación Celular/genética , Proliferación Celular/genética , Células Cultivadas , Femenino , Humanos , Masculino , Células Madre Mesenquimatosas/patología , MicroARNs/metabolismo , Osteoartritis/patología , Cultivo Primario de Células , Líquido Sinovial/citología , TransfecciónRESUMEN
Objective: To analyze clonal evolution and clinical significance of trisomy 8 in patients with acquired bone marrow failure. Methods: The clinical data of 63 patients with acquired bone marrow failure accompanied with isolated trisomy 8 (+8) from June 2011 to September 2018 were analyzed retrospectively, the clonal evolution patterns and relationship with immmunosuppressive therapy were summarized. Results: Totally 24 male and 39 female patients were enrolled, including 39 patients with aplastic anemia (AA) and 24 patients with relatively low-risk myelodysplastic syndrome (MDS) . Mean size of+8 clone in MDS patients[65% (15%-100%) ]was higher than that of AA patients[25% (4.8%-100%) , z=3.48, P=0.001]. The patients were was divided into three groups (<30%, 30%-<50%,and ≥50%) according to the proportion of+8 clone. There was significant difference among the three groups between AA[<30%:55.6% (20/36) ; 30-50%: 22.2% (8/36) ; ≥50%22.2% (8/36) ]and MDS patients[<30%:19.0% (4/21) ; 30%-<50%:19.0% (4/21) ; ≥50%61.9% (13/21) ] (P=0.007) . The proportion of AA patients with+8 clone <30% was significantly higher than that of MDS patients (P=0.002) ; and the proportion of AA patients with+8 clone ≥50%was significantly lower than that of MDS patients (P=0.002) . The median age of AA and MDS patients was respectively 28 (7-61) years old and 48.5 (16-72) years old. Moreover, there was no correlation between age and+8 clone size in AA or MDS (r(s)=0.109, P=0.125; r(s)=-0.022, P=0.924, respectively) . There was statistical difference in total iron binding capacity, transferrin and erythropoietin between high and low clone group of AA patients (P=0.016, P=0.046, P=0.012, respectively) , but no significant difference in MDS patients. The immunosuppressive therapy (IST) efficacy of AA and MDS patients was respectively 66.7% and 43.8% (P=0.125) . Comparing with initial clone size (27.3%) , the +8 clone size (45%) of AA patients was increased 1-2 year after IST, but no statistical difference (z=0.83, P=0.272) . Consistently, there was no significant change between initial clone size (72.5%) and 1-2 year clone size (70.5%) after IST in MDS patients. There was no significant difference in IST efficient rate between +8 clone size expansion and decline group of in AA patients at 0.5-<1, 1-2 and>2 years after IST. We found four dynamic evolution patterns of +8 clone, which were clone persistence (45%) , clone disappearance (30%) , clone emergence (10%) and clone recurrence (15%) . Conclusions: AA patients had a low clone burden, while MDS patients had a high burden of +8 clone. The +8 clone of AA patients didn't significantly expanded after IST, and the changes of +8 clone also had no effect on IST response.
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Anemia Aplásica , Evolución Clonal , Adolescente , Adulto , Anciano , Médula Ósea , Niño , Cromosomas Humanos Par 8 , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Trisomía , Adulto JovenRESUMEN
It is known that macroscopic properties of colloidal suspensions are often determined by the microstructure of the particles in the suspensions, depending on the interparticle, Brownian, and hydrodynamic (if any) forces. We take electrorheological (ER) fluids as an example. By using a computer simulation and an experimental approach, we investigate the structure of ER fluids subjected to both an electric field and a shear flow. The microstructure evolution from random structure, to chains, and then to stable lamellar patterns, observed in the experiments, agrees very well with that obtained in the simulations. It is shown that the formation of such lamellar patterns originates from the difference between the dipole moment induced in the particles suspended in the ER fluids without shear and the one with shear. The results on the relaxation process of structural formation and the internal structure of layers are also presented. Thus, it seems possible to achieve various structures and hence desired macroscopic properties of colloidal suspensions by adjusting external fields and, simultaneously, a shear flow.
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Simulación por Computador , Electricidad , Estructura Molecular , ReologíaRESUMEN
In our previous study we found that low power laser irradiation improved the erythrocyte deformability, but the mechanism is unclear. The membrane-attached hemoglobin (Hbm) may be one of the determining factors for the erythrocyte deformability. We report here for the first time, that laser irradiation can reduce the Hbm contents in pig's erythrocytes, providing the explanation for the improvement of erythrocyte deformability. The decrease of the Hbm was proportional to the irradiation dose, but the relative change of Hbm was saturated around 35%. The 532 nm laser was more efficient at lowering Hbm than the 632.8 nm laser, consistent with the absorption spectrum of Hbm.
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Membrana Eritrocítica/química , Membrana Eritrocítica/efectos de la radiación , Hemoglobinas/química , Hemoglobinas/efectos de la radiación , Terapia por Luz de Baja Intensidad , Animales , Deformación Eritrocítica/efectos de la radiación , Técnicas In Vitro , Fotobiología , Sus scrofaRESUMEN
The biochemical mechanisms involved in the actions of the atypical antipsychotic clozapine are still unclear. Because elevated levels of enkephalin in certain areas of the central nervous system may be necessary for antipsychotic activity, we have examined the effect of clozapine on certain receptors and mRNA transcripts involved in the opioid peptidergic system. Clozapine was infused continuously into mice for 21 days and the density of mu and delta opioid receptors was measured in the brains by quantitative receptor autoradiography, and the level of proenkephalin mRNA and dopamine D1 and D2 receptor mRNA were measured by in situ hybridization histochemistry. The results showed that continuous infusion of clozapine increased the density of D1 but not D2 receptors. However, it failed to alter the levels of either D1 or D2 dopamine receptor mRNA. By contrast, clozapine increased the density of mu and delta opioid receptors and increased the levels of proenkephalin mRNA. These results indicate that continuous treatment with clozapine increases opioid peptidergic activity in mouse brain and suggest that alteration of peptidergic activity as well as alteration of dopaminergic activity may be involved in its antipsychotic action.
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Encéfalo/efectos de los fármacos , Clozapina/farmacología , Encefalinas/genética , Precursores de Proteínas/genética , ARN Mensajero/genética , Receptores Opioides delta/genética , Receptores Opioides mu/genética , Animales , Autorradiografía , Expresión Génica/efectos de los fármacos , Bombas de Infusión Implantables , Masculino , Ratones , Receptores de Dopamina D1/genética , Receptores de Dopamina D2/genética , Transcripción Genética/efectos de los fármacosRESUMEN
D1 and D2 dopamine receptors mediate different behavioral effects in animals. We have attempted to selectively modulate dopamine-mediated behaviors by continuously administering D2 agonists to mice. Acute administration of the D2 agonist quinpirole caused dose-related stereotyped effects; no locomotor or grooming behavior was apparent. Continuously infusing quinpirole with implanted Alzet minipumps initially produced stereotyped behavior, but this stereotypy decreased by 2 hours, and was completely absent from 3 hours to 6 days of infusion. Within 1 day after implanting quinpirole, there appeared a significant locomotor behavior that continued for the 6 days of infusion. Acute challenge doses of quinpirole given either 6 days after infusing quinpirole or 12 hours after removing the quinpirole implant failed to elicit any stereotyped behavior and did not alter the locomotor behavior. By contrast, acute challenge injections with the D1 agonist SKF 38393 administered 12 hours after removing the quinpirole implant produced a characteristic grooming response. In an attempt to learn the mechanism of the behavioral effects induced by the continuous administration of quinpirole, the actions of relatively selective D1 and D2 antagonists were examined. The D2 antagonist sulpiride inhibited the stereotypy but not the locomotion induced by quinpirole. By contrast, the D1 antagonist Sch 23390 blocked the locomotion but not the stereotypy induced by quinpirole. These results indicate that chronic administration of quinpirole causes two separate behavioral effects: (1) a downregulation of stereotypy, perhaps by downregulating D2 receptors; and (2) the development of locomotion, which appears to involve both the downregulation of D2 receptors and an activation of D1 dopaminergic mechanisms.
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Ergolinas/farmacología , Actividad Motora/efectos de los fármacos , Conducta Estereotipada/efectos de los fármacos , 2,3,4,5-Tetrahidro-7,8-dihidroxi-1-fenil-1H-3-benzazepina/farmacología , Animales , Benzazepinas/farmacología , Dopaminérgicos/farmacología , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Implantes de Medicamentos , Ergolinas/administración & dosificación , Masculino , Ratones , Quinpirol , Receptores Dopaminérgicos/efectos de los fármacos , Receptores Dopaminérgicos/fisiología , Receptores de Dopamina D1 , Receptores de Dopamina D2 , Valores de ReferenciaRESUMEN
The effect of continuously infusing the selective D1 and D2 dopamine receptor agonists, SKF 38393 and quinpirole, on the release of [3H]acetylcholine from prelabeled striatal slices was investigated. These biochemical parameters were correlated with the behavioral effects of these agonists. Acute injections of SKF 38393 or quinpirole did not affect either K(+)-stimulated or spontaneous release of [3H]acetylcholine. Chronic exposure to quinpirole reduced the K(+)-evoked release of [3H]acetylcholine by 25.7%; long-term treatment with SKF 38393 did not alter the release of [3H]acetylcholine, induced by K+ stimulation. Added in vitro, SKF 38393 increased the release of [3H]acetylcholine from striatal slices. The effect of the D1 dopamine receptor agonist, SKF 38393 was reduced after 7-days of infusion of SKF 38393 but was enhanced by 7-days of infusion of quinpirole. Activation of D2 dopamine receptors with quinpirole or of muscarinic receptors with carbachol induced an inhibition of release of [3H]acetylcholine. Chronic treatment with quinpirole diminished the response to the in vitro addition of quinpirole. The ability of carbachol to inhibit release of acetylcholine was not altered by continuous treatment with either SKF 38393 or quinpirole. Continuous infusion of SKF 38393 produced an initial grooming behavior; this behavior disappeared by 2 hr and remained absent during the 7 days of infusion of SKF 38393. Similarly, continuous administration of quinpirole produced stereotyped behavior, which peaked at 1 hr and disappeared by 4 hr and remained absent for the duration of the infusion. These findings demonstrate that continuous exposure to D1 or D2 agonists caused receptor-selective functional desensitization of D1 or D2 dopamine receptors.(ABSTRACT TRUNCATED AT 250 WORDS)
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Acetilcolina/metabolismo , Cuerpo Estriado/metabolismo , Dopaminérgicos/farmacología , Receptores de Dopamina D1/efectos de los fármacos , Receptores de Dopamina D2/efectos de los fármacos , 2,3,4,5-Tetrahidro-7,8-dihidroxi-1-fenil-1H-3-benzazepina/farmacología , Animales , Carbacol/farmacología , Cuerpo Estriado/efectos de los fármacos , Ergolinas/farmacología , Aseo Animal/efectos de los fármacos , Técnicas In Vitro , Masculino , Ratones , Quinpirol , Receptores Muscarínicos/efectos de los fármacos , Conducta Estereotipada/efectos de los fármacosRESUMEN
To study further the molecular mechanisms by which glutamate and dopamine interact to regulate the functions of the basal ganglia, the effects of persistently inhibiting dopamine receptors and glutamate N-methyl-D-aspartate receptors on the density of D1 and D2 dopamine receptors and on the level of their transcripts were examined in mouse brain. To block dopamine receptors, mice were treated with N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline once daily for two and six days, or were treated with fluphenazine-N-mustard once daily for five days. To block N-methyl-D-aspartate receptors, mice were treated with dizocilpine by continuous infusion with osmotic mini-pumps for two and six days. The density of D1 and D2 dopamine receptors was measured by receptor autoradiography, and the level of D1 and D2 dopamine receptor messenger RNA was measured by in situ hybridization histochemistry. The results showed that N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline blocked about 90% of both D1 and D2 dopamine receptors, but had no significant effect on the level of either D1 or D2 dopamine receptor messenger RNA. Fluphenazine-N-mustard, which was as effective as N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline in blocking D2 dopamine receptors but had little effect on D1 dopamine receptors, also had no significant effect on the level of D1 and D2 dopamine receptor messenger RNAs. By contrast, continuously infusing dizocilpine significantly decreased the levels of D2 dopamine receptor messenger RNA in striatum, nucleus accumbens and olfactory tubercle. Dizocilpine also caused small decreases in the density of D2 dopamine receptors, but only in posterior striatum was this decrease statistically significant. Dizocilpine slightly and transiently decreased the levels of D1 dopamine receptor messenger RNA in striatum but had no significant effect on the density of D1 dopamine receptors in any region examined. This study demonstrates that persistent blockade of D1 and D2 dopamine receptors has relatively little effect on the levels of D1 and D2 dopamine receptor messenger RNA, but that blockade of N-methyl-D-aspartate receptors produces a rapid and profound decrease in the levels of D2 dopamine receptor messenger RNA and a smaller decrease in the density of D2 dopamine receptors. These results suggest that N-methyl-D-aspartate receptors play an important role in the expression of D2 dopamine receptors in basal ganglia.
Asunto(s)
Antagonistas de los Receptores de Dopamina D2 , Antagonistas de Aminoácidos Excitadores , ARN Mensajero/biosíntesis , Receptores de Dopamina D1/antagonistas & inhibidores , Receptores de Dopamina D2/biosíntesis , Animales , Autorradiografía , Ganglios Basales/efectos de los fármacos , Ganglios Basales/metabolismo , Química Encefálica/efectos de los fármacos , Maleato de Dizocilpina/farmacología , Flufenazina/análogos & derivados , Flufenazina/farmacología , Hibridación in Situ , Masculino , Ratones , Quinolinas/farmacologíaRESUMEN
There are several subtypes of dopamine receptors in the central nervous system which mediate the actions of dopamine in producing its diverse motor and behavioral effects. In this study we determined whether an antisense oligodeoxynucleotide directed to the mRNA encoding one of the subtypes of the dopamine receptor can inhibit a specific dopamine-mediated behavior. Accordingly, the effects of a phosphorothioate-modified antisense oligodeoxynucleotide targeted toward the D2 dopamine receptor mRNA (D2 antisense) was studied in mice with unilateral 6-hydroxydopamine-induced lesions of the corpus striatum. Rotational behavior in response to different agents, and the levels of D2 and D1 dopamine receptors and D2 and D1 dopamine receptor mRNAs in corpus striatum were then measured. In control mice, lesioning resulted in a contralateral rotational behavior in response to the D1 dopamine receptor agonist SKF 38393, the D2 dopamine agonist quinpirole, and the muscarinic cholinergic agonist oxotremorine. Lesioning also caused an increase in D2 dopamine receptor mRNA levels in the dorsolateral striatum. Intraventricular injections of the D2 antisense inhibited rotational behavior induced by quinpirole but not that induced by SKF 38393 or that induced by oxotremorine. Repeated administration of the D2 antisense significantly reduced the levels of the D2 dopamine receptor and D2 dopamine receptor mRNA in the dorsolateral but not the dorsomedial striatum. Similar treatment failed to significantly alter the levels of the D1 dopamine receptor or D1 receptor mRNA in dorsolateral or dorsomedial striatum.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
ADN sin Sentido/farmacología , Antagonistas de Dopamina , Actividad Motora/efectos de los fármacos , Oligodesoxirribonucleótidos/farmacología , ARN Mensajero/genética , 2,3,4,5-Tetrahidro-7,8-dihidroxi-1-fenil-1H-3-benzazepina/farmacología , Animales , Secuencia de Bases , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Ergolinas/antagonistas & inhibidores , Ergolinas/farmacología , Inyecciones Intraventriculares , Masculino , Ratones , Datos de Secuencia Molecular , Actividad Motora/genética , Oxidopamina/toxicidad , Oxotremorina/farmacología , Quinpirol , ARN Mensajero/antagonistas & inhibidores , ARN Mensajero/biosíntesis , Receptores Dopaminérgicos/genética , RotaciónRESUMEN
To determine the uptake and distribution of oligodeoxynucleotides in brain, a 20-mer phosphorothioated oligodeoxynucleotide complementary to a portion of the D2 dopamine receptor mRNA was fluorescently labeled with fluorescein isothiocyanate (FITC) and injected into the lateral cerebral ventricles of mice. At various survival times after the injection, the brains were removed, fixed, sectioned, and viewed under a fluorescent microscope. The results showed that the oligodeoxynucleotide was rapidly taken up into the brain. Initially the label was relatively diffusely spread throughout the interstitial spaces of the brain, then became redistributed to the cellular compartments. The signal extended from those forebrain nuclei located immediately in contact with the ventricles, such as the corpus striatum, septum, and hippocampus, to areas further removed from the ventricles, such as the cerebral cortex, nucleus accumbens, and substantia nigra. When the FITC-labeled D2 antisense oligodeoxynucleotide was given once daily for 4 d, the signal intensity seen 24 h after the last injection appeared to be of greater intensity overall compared to that seen after a single injection. At early time-points the oligodeoxynucleotide signals appeared to be punctuated and were found in cell bodies as well as in proximal dendritic processes. However, not all cells were equally labeled, suggesting an uneven uptake and accumulation of the D2 antisense into the various cell types. At later time-points the fluorescent signal appeared granular; at these times the injected material was largely degraded. These studies show that a D2 dopamine receptor antisense oligodeoxynucleotide is rapidly taken up from cerebral ventricles into brain, becomes widely distributed throughout the brain tissue to areas far removed from direct contact with the ventricles, and appears to accumulate to a different extent in the various brain areas and cell types.
Asunto(s)
Elementos sin Sentido (Genética)/farmacocinética , Encéfalo/metabolismo , Oligodesoxirribonucleótidos/farmacocinética , Receptores de Dopamina D2/genética , Tionucleótidos/farmacocinética , Animales , Encéfalo/citología , Química Encefálica , Ventrículos Cerebrales/metabolismo , Espacio Extracelular/metabolismo , Fluoresceína , Fluoresceínas , Inyecciones Intraventriculares , Masculino , Ratones , Fibras Nerviosas/metabolismo , Neuronas/metabolismoRESUMEN
Previous studies have shown that the intracerebroventricular injection of antisense oligodeoxynucleotides targeted to the mRNAs encoding the different subtypes of dopamine receptors inhibited behaviors mediated by these receptors. The present studies were designed to determine whether such antisense oligodeoxynucleotides could produce similar effects when injected into a discrete brain area. A D2 dopamine receptor antisense oligodeoxynucleotide (D2 antisense) was repeatedly injected into one corpus striatum of either normal mice or mice with unilateral lesions of the striatum induced by 6-hydroxydopamine. In the latter, intrastriatal injection of D2 antisense blocked the contralateral rotational behavior induced by the parenteral administration of the D2 dopamine receptor agonist quinpirole. The inhibitory effect of D2 antisense was dose- and time-related and was reversed upon cessation of D2 antisense treatment. This inhibitory effect was also selective in that D2 antisense treatment inhibited the rotational behavior induced by quinpirole but not that induced by the D1 dopamine receptor agonist SKF 38393 or by the muscarinic cholinergic agonist oxotremorine. Following repeated intrastriatal injections of D2 antisense into normal mice, parenteral administration of quinpirole caused rotational behavior ipsilateral to the side in which the D2 antisense was injected. No such rotational behavior was seen when similarly treated mice were challenged with SKF 38393 or oxotremorine. The quinpirole-induced rotational behavior in mice given intrastriatal injections of D2 antisense disappeared upon cessation of D2 antisense treatment. Repeated intrastriatal administration of D2 antisense also caused a significant reduction in the levels of D2, but not D1, dopamine receptors in striatum, as determined by receptor autoradiography. The levels of D2 dopamine receptors returned to normal upon cessation of D2 antisense treatment. Intrastriatal administration of an oligodeoxynucleotide with randomly placed nucleotides failed to alter the rotational response to quinpirole in either 6-hydroxydopamine-lesioned or normal mice and failed to alter the levels of D2 dopamine receptors in striatum. These results show that selective inhibition of behavioral responses mediated by D2 dopamine receptors can be achieved by the direct injection of a D2 antisense oligodeoxynucleotide into a discrete brain area.