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1.
Eur Rev Med Pharmacol Sci ; 24(12): 6551-6560, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32633342

RESUMO

OBJECTIVE: As a new LncRNA, anti-differentiated non-coding RNA (DANCR) plays an important role in tumorigenesis and development, and its molecular mechanism in osteosarcoma is unclear. In this study, by investigating osteosarcoma tissue and cells, we explored the molecular mechanism by which lncRNA DANCR regulates the occurrence and development of osteosarcoma by targeting the miR-149 / MSI2 axis. PATIENTS AND METHODS: In this study, osteosarcoma tissues and adjacent tissues in 109 patients were collected, and the relative expression of DANCR was detected by qPCR. The correlation between DANCR expression and clinical classification was statistically analyzed. In order to explore the potential molecular mechanism of DANCR related to tumor migration and invasion, an overexpression and silencing test was performed on the osteosarcoma cell line Saos-2, and then qPCR method was used to test the expression of miR149, and cell scratch test was used to detect invasion after DANCR silencing and miR149 overexpression. Transwell assay was used to detect the invasion after DANCR silencing and miR149 overexpression. Finally, Western blot was used to verify the expression of MSI2 protein after overexpression and silencing of miR-149. RESULTS: DANCR was significantly up-regulated in both osteosarcoma tissue and cells. The high expression of DANCR was significantly positively correlated with tissue typing and advanced TNM stage. DANCR can significantly reduce the migration and invasion of osteosarcoma cells. miRNA overexpression significantly reduced osteosarcoma cell migration and invasion. When miR-149 was overexpressed, MSI2 protein expression was significantly down-regulated. When miR-149 was silenced, MSI2 protein was significantly up-regulated. CONCLUSIONS: LncRNA DANCR plays an important regulatory role in the occurrence and development of osteosarcoma. It may be used as a potential target in the treatment of osteosarcoma in the future, by targeting the miR-149/MSI2 axis to regulate the occurrence and development of osteosarcoma.


Assuntos
Neoplasias Ósseas/metabolismo , Movimento Celular/fisiologia , MicroRNAs/biossíntese , Osteossarcoma/metabolismo , RNA Longo não Codificante/biossíntese , Proteínas de Ligação a RNA/biossíntese , Adulto , Neoplasias Ósseas/patologia , Feminino , Humanos , Masculino , MicroRNAs/antagonistas & inibidores , Invasividade Neoplásica/patologia , Osteossarcoma/patologia , Proteínas de Ligação a RNA/antagonistas & inibidores , Adulto Jovem
2.
Zhonghua Wai Ke Za Zhi ; 57(7): 523-526, 2019 Jul 01.
Artigo em Chinês | MEDLINE | ID: mdl-31269615

RESUMO

Objective: To explore the clinical effect and safety of minor liver resection for hilar cholangiocarcinoma (HC) of Bismuth-Corlette type Ⅲ and Ⅳ. Methods: From May 2007 to May 2017, the clinical data of 108 patients with Bismuth-Corlette type Ⅲ and Ⅳ HC underwent hepatectomy were collected and analyzed retrospectively.There were 56 males and 52 females, aged (57.2±5.3) years (ranged 48-76 years) .Among the 108 cases, there were 51 cases of type Ⅲa, 40 cases of type Ⅲb and 17 cases of type Ⅳ. Small-scale hepatectomy (≤3 hepatectomy) was performed in 70 cases, including 8 cases of 4b segment resection, 28 cases of 4b segment+5 segment resection, and 34 cases of partial 4 segment+partial 7 segment+partial 1 segment resection. Large-scale hepatectomy was performed in 38 cases (>3 segments) , of which 30 cases were treated with 2 segments+3 segments+4 segments+1 segment, and 8 cases were treated with 5 segments+7 segments+8 segments+1 segment. t' test was used to analyze the data which did not conform to the normal distribution, and χ(2) test was used to calculate the incidence of postoperative complications and the 1, 3, and 5-year cumulative overall survival rate. Results: (1) The operation time of minor liver resection group ((180±25)minutes) was shorter than that of major liver resection group ((210±35)minutes) (t'=4.676, P<0.05) , the amount of blooding operation time of minor liver resection group ((310±80)ml) was less than that of major liver resection group ((500±110)ml)in the operation (t'=9.385, P<0.05) , and the difference was statistically significant. (2) The incidence of complications was lower in minor liver resection group and major liver resection group, and the difference was statistically significant (χ(2)=5.230, P<0.05) . (3) The actual 1-, 3- and 5-year survival rates were 87.1%, 58.4%, 30.0% and 84.2%, 57.9%,31.6%, respectively. There were no significant differences in survival rates in two groups in 1-, 3- and 5-year survival rates (χ(2)=0.177, P=0.674; χ(2)=0.005, P=0.946; χ(2)=0.029, P=0.865) . Conclusions: Compared to patients with major liver resection, Minor liver resection for selected patients with HC of Bismuth-Corlette Ⅲ and Ⅳaccording to our criteria achieved better long-term outcomes. Chen's biliojejunostomy is a simple, effective and safe method, which can be widely used when there are multiple biliary intestinal anastomosese.


Assuntos
Neoplasias dos Ductos Biliares/cirurgia , Hepatectomia/métodos , Tumor de Klatskin/cirurgia , Idoso , Neoplasias dos Ductos Biliares/classificação , Feminino , Humanos , Tumor de Klatskin/classificação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
3.
Transplant Proc ; 50(1): 79-84, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29407336

RESUMO

BACKGROUND: Donation after cardiac death is the only source of the deceased donor in China at present. Hypothermic machine perfusion has been used increasingly over the years. We determined the hypothermic machine perfusion parameters associated with early transplant outcomes based on the expanded criteria donor (ECD) designation. METHODS: There were 446 consecutive kidneys donated after cardiac death and preserved by hypothermic machine perfusion (LifePort) in our center that were included in this study. The database was divided into 2 groups: ECD and non-ECD groups. LifePort parameters and other pretransplant factors were analyzed. Logistic regression analysis was used to determine the significant factors for delayed graft function (DGF). Recovery time for renal function and 6-months serum creatinine were investigated. RESULTS: The DGF rates were 20.25% and 11.72% in ECD and non-ECD group by our definition, respectively (P = .042). Higher pressures allowed comparable increases of flow in ECD kidneys despite still greater resistance. For non-ECD kidneys with an initial flow of ≤80 mL/min, the DGF rate of the subgroup with a terminal flow of ≥100 mL/min was significantly lower compared with that of other terminal flow subgroups (≤80 and 90-100 mL/min; P < .05), and showed a trend toward significance when compared with the terminal flow subgroup of 80 to 90 mL/min (P = .098). Terminal resistance was the most significant parameter predicting DGF (odds ratio 2.44; P < .001), and remained significant after adjusted for other relevant pretransplant variables. Logistic model for DGF (model: terminal resistance, hypotension in agonal phase, terminal serum creatinine, and cause of death) had good predictive ability (c-statistic 0.851; 95% confidence interval, 0.799-0.903). CONCLUSIONS: LifePort parameters provided a granular measurement easily accessible in evaluating the quality of kidneys donated after cardiac death that added information to ECD criterion.


Assuntos
Morte , Função Retardada do Enxerto/etiologia , Transplante de Rim/efeitos adversos , Preservação de Órgãos/efeitos adversos , Perfusão/efeitos adversos , China , Bases de Dados Factuais , Feminino , Humanos , Rim/fisiopatologia , Transplante de Rim/métodos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Preservação de Órgãos/métodos , Perfusão/métodos , Fatores de Tempo , Doadores de Tecidos/provisão & distribuição , Transplantes/fisiopatologia , Resultado do Tratamento
4.
Am J Transplant ; 16(2): 615-24, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26460900

RESUMO

The role of autotransplantation in end-stage hepatic alveolar echinococcosis (AE) is unclear. We aimed to present our 15-case experience and propose selection criteria for autotransplantation. All patients were considered to have unresectable hepatic AE by conventional resection due to critical invasion to retrohepatic vena cava, hepatocaval region along with three hepatic veins, and the tertiary portal and arterial branches. All patients successfully underwent ex vivo extended right hepatectomy and autotransplantation without intraoperative mortality. The median autograft weight was 706 g (380-1000 g); operative time was 15.5 hours (11.5-20.5 hours); and anhepatic time was 283.8 minutes (180-435 min). Postoperative hospital stay was 32.3 days (12-60 days). Postoperative complication Clavien-Dindo grade IIIa or higher occurred in three patients including one death that occurred 12 days after the surgery due to acute liver failure. One patient was lost to follow-up after the sixth month. Thirteen patients were followed for a median of 21.6 months with no relapse. This is the largest reported series of patients with end-stage hepatic AE treated with liver autotransplantation. The technique requires neither organ donor nor postoperative immunosuppressant. The early postoperative mortality was low with acceptable morbidity. Preoperative precise assessment and strict patient selection are of utmost importance.


Assuntos
Equinococose Hepática/cirurgia , Hepatectomia , Veias Hepáticas/cirurgia , Transplante de Fígado , Veia Cava Inferior/cirurgia , Adolescente , Adulto , Feminino , Seguimentos , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Transplante Autólogo , Adulto Jovem
5.
Opt Lett ; 38(11): 1942-4, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23722797

RESUMO

Theoretical and experimental investigations of the behavior of normal-dispersion fiber lasers with nonlinear optical loop mirrors are presented. The use of a loop mirror causes the laser to generate relatively long, flat-topped pulses. The pulse energy can be high, but the pulse duration is limited to greater than 300 fs. Experimentally, 8 nJ pulses that can be dechirped to 340 fs duration are obtained. The laser is a step toward an all-fiber, environmentally stable design.


Assuntos
Lasers , Dinâmica não Linear , Fenômenos Ópticos
6.
Parasite Immunol ; 34(11): 520-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22803774

RESUMO

Echinococcosis is a chronic parasitic infectious disease regulated by T-cell subsets. CD4(+) CD25(+) FoxP3 (+) regulatory T (Treg) cells and Th17 cells have been described as two distinct subsets and have the opposite effect on inflammation. Th17/Treg balance controls inflammation and may play an important role in the pathogenesis of immune evasion. To assess whether this balance was broken, we detected Th17/Treg functions in different levels including cell frequencies, related cytokines secretion and key transcription factors in patients with cystic echincoccosis and healthy controls. The results demonstrated that patients with cystic echinococcosis revealed significant increase in peripheral Treg number, related cytokines (IL-10 and TGF-ß1) and transcription factor (Foxp3) levels and moderate decrease in Th17 number, related cytokines (IL-17 and IL-23) and transcription factor (RORγt) levels as compared with controls. Results indicated that Th17/Treg functional imbalance exists in patients with chronic cystic echinococcosis, suggesting a potential role for Th17/Treg imbalance in the pathogenesis of immune evasion in echinococcosis.


Assuntos
Equinococose Hepática/imunologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Adulto , Doença Crônica , Citocinas/metabolismo , Feminino , Fatores de Transcrição Forkhead/biossíntese , Perfilação da Expressão Gênica , Humanos , Masculino , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/biossíntese
7.
J Trauma ; 63(6): 1308-13, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18212654

RESUMO

INTRODUCTION: The ideal timing of spinal fixation is controversial. A recent study showed that early spine fixation reduced morbidity and resource utilization. We previously noted a trend toward higher mortality in patients undergoing early spinal fixation. This study was done to analyze whether the timing of spinal fixation had a significant effect on mortality. METHODS: The registry of our Level I trauma program was queried for all patients with at least one spinal vertebral injury. Anatomic and physiologic variables included age, initial Glasgow Coma Scale score, systolic blood pressure, heart rate, and Injury Severity Score. Outcome was evaluated in terms of ventilator days, intensive care unit length of stay, hospital length of stay (HLOS), and mortality. Patients were stratified by day of spinal operative fixation as early when done within 48 hours and late when done after 48 hours. Data were analyzed using chi and an unpaired t test, accepting p < 0.05 as significant. RESULTS: Three hundred sixty-one patients between January 1988 and February 2003 required operative spinal fixation (158 early, within 48 hours vs. 203 late, beyond 48 hours). There was no significant difference between the two groups except mortality, which was significantly higher in the early group (7.6 vs. 2.5%; p = 0.0257), and HLOS, which was significantly shorter in the early group (14.42 vs. 17.64 days; p = 0.025). CONCLUSION: Spinal fixation within 48 hours after vertebral fractures and dislocations appears to increase mortality despite similar anatomic and physiologic parameters in the later operative group. Incomplete resuscitation of patients before surgery may have contributed to this result. The shorter HLOS may have been because of the higher number of early deaths. Prospective studies to identify the optimal timing of spinal fixation and the reason for these outcome differences are warranted.


Assuntos
Vértebras Cervicais/lesões , Fixação Interna de Fraturas/estatística & dados numéricos , Vértebras Lombares/lesões , Fraturas da Coluna Vertebral/cirurgia , Vértebras Torácicas/lesões , Centros de Traumatologia/estatística & dados numéricos , Ferimentos não Penetrantes/cirurgia , Adulto , Feminino , Fixação Interna de Fraturas/efeitos adversos , Humanos , Escala de Gravidade do Ferimento , Masculino , Pneumonia/etiologia , Complicações Pós-Operatórias , Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/mortalidade , Fatores de Tempo , Ferimentos não Penetrantes/etiologia , Ferimentos não Penetrantes/mortalidade
8.
J Hand Surg Am ; 27(3): 402-8, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12015713

RESUMO

The cause and importance of increased density of the proximal pole of the scaphoid seen in radiographs after an acute fracture were investigated. Blood flow to the proximal poles of 32 nonsurgically treated scaphoid fractures were assessed 1 to 2 weeks after injury by measuring their uptake of gadopentetate dimeglumine with dynamic magnetic resonance imaging and calculating its steepest slope and percentage of enhancement values. Initial (week 0) and week 8 scaphoid series radiographs were independently assessed by 2 observers for increased proximal pole density; both agreed that the density had increased during treatment in 9 fractures. All 9 fractures united, suggesting that increased proximal pole density is not a major determinant of fracture outcome. Increased density of the proximal pole was associated with low proximal pole blood flow, but this relationship was not absolute, suggesting that other factors contribute to the appearance of increased density.


Assuntos
Fraturas Ósseas/terapia , Angiografia por Ressonância Magnética/métodos , Osteosclerose/diagnóstico , Osso Escafoide/lesões , Osso Escafoide/fisiopatologia , Adolescente , Adulto , Idoso , Velocidade do Fluxo Sanguíneo , Feminino , Fixação de Fratura/instrumentação , Consolidação da Fratura/fisiologia , Fraturas Ósseas/diagnóstico , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/métodos , Variações Dependentes do Observador , Aparelhos Ortopédicos , Probabilidade , Estudos Prospectivos , Sensibilidade e Especificidade , Estatísticas não Paramétricas , Fatores de Tempo
9.
Brain Res ; 808(2): 141-54, 1998 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-9767152

RESUMO

Immunocytochemical studies were performed to determine the distribution and cellular localization of the NMDA-R2A receptor subunit (R2A) in the cat retina. R2A-immunoreactivity (R2A-IR) was noted in all layers of the retina, with specific localizations in the outer segments of red/green and blue cone photoreceptors, B-type horizontal cells, several types of amacrine cells, Müller cells and the majority of cells in the ganglion cell layer. In the inner nuclear layer, 48% of all cells residing in the amacrine cell layer were R2A-IR including a cell resembling the GABAergic A17 amacrine cell. Interestingly, the AII rod amacrine cell was devoid of R2A-IR. Although the localization of the R2A subunit was anticipated in ganglion cells, amacrines and Müller cells, the presence of this receptor subunit to the cells in the outer retina was not expected. Here, both the R2A and the R2B subunits were found to be present in the outer segments of cone photoreceptors and to the tips of rod outer segments. Although the function of these receptor subunits in rod and cone photoreceptors remains to be determined, the fact that both R2A and R2B receptor subunits are localized to cone outer segments suggests a possible alternative pathway for calcium entry into a region where this cation plays such a crucial role in the process of phototransduction. To further classify the cells that display NR2A-IR, we performed dual labeling experiments showing the relationship between R2A-labeled cells with GABA. Results showed that all GABAergic-amacrines and displaced amacrines express the R2A-subunit protein. In addition, approximately 11% of the NR2A-labeled amacrines, did not stain for GABA. These findings support pharmacological data showing that NMDA directly facilitates GABA release in retina and retinal cultures [I.L. Ferreira, C.B. Duarte, P.F. Santos, C.M. Carvalho, A.P. Carvalho, Release of [3H]GABA evoked by glutamate receptor agonist in cultured chick retinal cells: effect of Ca2+, Brain Res. 664 (1994) 252-256; G.D. Zeevalk, W.J. Nicklas, Action of the anti-ischemic agent ifenprodil on N-methyl-d-aspartate and kainate-mediated excitotoxicity, Brain Res. 522 (1990) 135-139; R. Huba, H.D. Hofmann, Transmitter-gated currents of GABAergic amacrine-like cells in chick retinal cultures, Vis. Neurosci. 6 (1991) 303-314; M. Yamashita, R. Huba, H.D. Hofmann, Early in vitro development of voltage- and transmitter-gated currents in GABAergic amacrine cells, Dev. Brain Res. 82 (1994) 95-102; R. Ientile, S. Pedale, V. Picciurro, V. Macaione, C. Fabiano, S. Macaione, Nitric oxide mediates NMDA-evoked [3H]GABA release from chick retina cells, FEBS Lett. 417 (1997) 345-348; R.C. Kubrusly, M.C. deMello, F.G. deMello, Aspartate as a selective NMDA agonist in cultured cells from the avian retina, Neurochem. Intl. 32 (1998) 47-52] or reduction of GABA in vivo [N.N. Osborn, A.J. Herrera, The effect of experimental ischaemia and excitatory amino acid agonist on the GABA and serotonin immunoreactivities in the rabbit retina, Neurosci. 59 (1994) 1071-1081]. Since the majority of GABAergic synapses in the inner retina are onto both rod and cone bipolar axon terminals [R.G. Pourcho, M.T. Owzcarzak, Distribution of GABA immunoreactivity in the cat retina: A light and electron-microscopic study, Vis. Neurosci. 2 (1989) 425-435], we hypothesize that the NMDA-receptor plays a crucial role in providing feedback inhibition onto rod and cone bipolar cells.


Assuntos
Receptores de N-Metil-D-Aspartato/análise , Células Fotorreceptoras Retinianas Cones/química , Células Ganglionares da Retina/química , Animais , Especificidade de Anticorpos , Western Blotting , Calbindinas , Gatos , Proteínas do Olho/análise , Proteínas do Olho/imunologia , Imuno-Histoquímica , Parvalbuminas/análise , Parvalbuminas/imunologia , Ratos , Receptores de N-Metil-D-Aspartato/imunologia , Proteína G de Ligação ao Cálcio S100/análise , Proteína G de Ligação ao Cálcio S100/imunologia , Coloração pela Prata , Ácido gama-Aminobutírico/análise , Ácido gama-Aminobutírico/imunologia
10.
J Comp Neurol ; 386(4): 613-24, 1997 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-9378855

RESUMO

The present study was conducted to examine the plasticity of 5-hydroxytryptamine (5-HT)-immunoreactive terminals in the rat phrenic nucleus following an ipsilateral C2 spinal cord hemisection and 30-day survival period. A retrograde horseradish peroxidase (HRP) labeling technique was used to identify the phrenic motoneurons at the electron microscopic (EM) level. After employing a pre-embedding immunocytochemical technique, the ultrastructural characteristics of 5-HT-immunoreactive terminals were qualitatively and then quantitatively analyzed with a computerized morphometric system before and after injury in separate groups of rats. The results indicated that the majority of the 5-HT-labeled terminals formed axodendritic contacts, but some 5-HT-labeled terminals made axosomatic contacts. 5-HT terminals were associated with either asymmetrical or symmetrical synapses, and some displayed postsynaptic dense bodies. Approximately 2% of the 5-HT terminals had dense-core vesicles. Although the total number of labeled and unlabeled terminals in the phrenic nucleus was reduced after hemisection, the number of 5-HT terminals in the hemisected group was greater than that of the control group. Moreover, the total number and length of asymmetrical and symmetrical synaptic active zones per 5-HT terminal were significantly greater after injury. Finally, the total number of 5-HT terminals with multiple synapses was significantly greater in the hemisected group as compared to controls. It is possible that 5-HT synaptic plasticity may be part of the morphological substrate for the unmasking of the latent crossed phrenic pathway which mediates recovery of the ipsilateral hemidiaphragm paralyzed by C2 spinal cord hemisection.


Assuntos
Plasticidade Neuronal/fisiologia , Nervo Frênico/química , Terminações Pré-Sinápticas/imunologia , Receptores de Serotonina/imunologia , Traumatismos da Medula Espinal/patologia , Animais , Cordotomia , Feminino , Microscopia Eletrônica , Neurônios Motores/química , Neurônios Motores/patologia , Neurônios Motores/ultraestrutura , Nervo Frênico/citologia , Terminações Pré-Sinápticas/química , Terminações Pré-Sinápticas/ultraestrutura , Ratos , Ratos Sprague-Dawley , Receptores de Serotonina/análise , Receptores de Serotonina/ultraestrutura , Traumatismos da Medula Espinal/cirurgia , Sinapses/química
11.
J Spinal Cord Med ; 20(3): 311-8, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9261776

RESUMO

The present study was designed to: 1) morphologically characterize cat glutamate and GABAergic synaptic terminals in lamina IX in the intact spinal cord at the electron microscopic level using postembedding immunochemical techniques and .2), begin an analysis of how the synaptic architecture of glutamate and GABAergic terminals changes after an ipsilateral spinal cord hemisection. The present study shows that glutamate immunoreactive terminals are characterized by a wide synaptic cleft, asymmetric synaptic membrane densities and spherical synaptic vesicles. Most of the glutamatergic terminals are presynaptic to small or medium size dendrites. In contrast, GABAergic terminals display typical pleomorphic synaptic vesicles, a narrow synaptic cleft and a symmetrical membrane density. Qualitative analysis indicated that 13-17 months after hemisection, the length of the synaptic active zones in both glutamatergic and GABAergic terminals ipsilateral to hemisection is longer than those observed in the terminals contralateral to hemisection orfin normal control cats. Furthermore, the perimeters of both dendrites and either glutamate or GABA immunoreactive terminals are longer on the hemisected side compared with those observed in the nonhemisected side of the spinal cord. The results are important for complete understanding of the mechanisms which underlie locomotor recovery in mammals following spinal cord injury.


Assuntos
Glutamina/metabolismo , Terminações Nervosas/metabolismo , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Medula Espinal/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Gatos , Microscopia Eletrônica , Terminações Nervosas/ultraestrutura , Medula Espinal/patologia , Sinapses/metabolismo , Sinapses/ultraestrutura
12.
J Comp Neurol ; 372(3): 343-55, 1996 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-8873865

RESUMO

Quantitative analysis of electron microscopic postembedding immunochemically stained material indicates that 48% of all terminals in the rat phrenic nucleus are glutamatergic and 33% are gamma-aminobutyric acid (GABA)ergic. Three distinct types of glutamatergic terminals were observed in the rat phrenic nucleus: terminals characterized by large, loosely arranged spherical synaptic vesicles (SI) or small, compact spherical synaptic vesicles (Ss) and elongated terminals containing spherical synaptic vesicles with neurofilaments (NFs). All three types of glutamatergic terminals display asymmetrical synaptic membrane densities with postsynaptic dense bodies being present in some of the S-type terminals. The GABAergic immunoreactive terminals in the phrenic nucleus most closely resemble F-type terminals. They are characterized by flattened or pleomorphic synaptic vesicles and symmetric synaptic membrane densities. Among the 48% glutamatergic terminals, 27% are SI, 65% are Ss, and 8% are NFs, respectively. Significantly fewer glutamate, GABA, and unlabeled terminals per unit area are present in the phrenic nucleus 30 days after a C2 spinal cord hemisection as compared to nonhemisected controls. The average number of active zones per terminal, however, is greater in the hemisection group (1.45 +/- 0.03) than in the control group (1.34 +/- 0.03), with the active zones in the glutamate terminals mainly accounting for this difference. Moreover, the length of the active zones in the glutamate terminals was significantly longer in the hemisection group (0.37 +/- 0.013 microns) as compared to the controls (0.24 +/- 0.008 microns). In addition, the mean length of synaptic active zones in GABAergic terminals was also found to be longer in the hemisection group (0.36 +/- 0.022 microns) as compared to controls (0.28 +/- 0.014 microns). Finally, there is also a significantly higher ratio of synaptic active zones to the total number of glutamate-labeled terminals after injury (1.73 +/- 0.08) as compared to controls (1.41 +/- 0.04). The number of double/multiple synapses, the percentages of Sl, Ss, and NFs-type terminals, and the percentages of synaptic active zones contacting either distal dendrites or proximal dendrites/somata do not change significantly 30 days after injury. These results are important for a more complete understanding of the synaptic plasticity that occurs in the phrenic nucleus after spinal cord injury and to show how the plasticity may relate to the unmasking of latent bulbospinal respiratory connections which restore function to the hemidiaphragm paralyzed by an ipsilateral spinal cord hemisection.


Assuntos
Ácido Glutâmico/metabolismo , Neurônios Motores/ultraestrutura , Terminações Pré-Sinápticas/ultraestrutura , Traumatismos da Medula Espinal/patologia , Ácido gama-Aminobutírico/metabolismo , Animais , Feminino , Imuno-Histoquímica , Microscopia Eletrônica , Ratos , Ratos Sprague-Dawley
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