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To reveal the changes in the life history characteristics of grassland plants due to vegetation restoration, plant species and communities were analyzed for their competitor, stress tolerator, and ruderal (CSR) ecological strategies after the introduction of woody plants in the damaged steppe grassland and were compared with those in reference sites in Hulunbuir, Inner Mongolia. As a result, it was found that the introduction of the woody plants (Corethrodeneron fruticosum, Caragana microphylla, Populus canadensis, and Pinus sylvestris var. mongolica) into the damaged land greatly increased the plant species diversity and CSR eco-functional diversity as the succession progressed. The plant strategies of the temperate typical steppe (TTS) and woodland steppe (WS) in this Asian steppe are CSR and S/SR, respectively, which means that the plants are adapted to disturbances or stress. As the restoration time elapsed in the damaged lands exhibiting (R/CR) (Corispermum hyssopifolium), the ecological strategies were predicted to change in two ways: (1) âR/CSR (Cynanchum thesioides, Astragalus laxmannii, etc.) â CSR in places (TSS) (Galium verum var. asiaticum, Saussurea japonica, etc.) where only shrubs were introduced, and (2) â S/SR (Allium mongolicum, Ulmus pumila, etc.) â S/SR in sites (WS) (Ulmus pumila, Thalictrum squarrosum, etc.) where trees and shrubs were planted simultaneously. The results mean that the driving force that causes succession in the restoration of temperate grasslands is determined by the life-form (trees/shrubs) of the introduced woody plants. This means that for the restoration of these grasslands to be successful, it is necessary to introduce woody tree species at an early stage.
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Although much effort has been directed at dissecting the mechanisms of central tolerance, the role of thymic stromal cells remains elusive. In order to further characterize this event, we developed a mouse model restricting LacZ to thymic stromal cotransporter (TSCOT)-expressing thymic stromal cells (TDLacZ). The thymus of this mouse contains approximately 4,300 TSCOT+ cells, each expressing several thousand molecules of the LacZ antigen. TSCOT+ cells express the cortical marker CDR1, CD40, CD80, CD54, and major histocompatibility complex class II (MHCII). When examining endogenous responses directed against LacZ, we observed significant tolerance. This was evidenced in a diverse T cell repertoire as measured by both a CD4 T cell proliferation assay and an antigen-specific antibody isotype analysis. This tolerance process was at least partially independent of Autoimmune Regulatory Element gene expression. When TDLacZ mice were crossed to a novel CD4 T cell receptor (TCR) transgenic reactive against LacZ (BgII), there was a complete deletion of double-positive thymocytes. Fetal thymic reaggregate culture of CD45- and UEA-depleted thymic stromal cells from TDLacZ and sorted TCR-bearing thymocytes excluded the possibility of cross presentation by thymic dendritic cells and medullary epithelial cells for the deletion. Overall, these results demonstrate that the introduction of a neoantigen into TSCOT-expressing cells can efficiently establish complete tolerance and suggest a possible application for the deletion of antigen-specific T cells by antigen introduction into TSCOT+ cells.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Epiteliais/imunologia , Tolerância Imunológica , Óperon Lac/imunologia , Simportadores/imunologia , Timo/citologia , Animais , Células Apresentadoras de Antígenos/imunologia , Diferenciação Celular , Células Dendríticas/citologia , Células Dendríticas/imunologia , Ativação Linfocitária , Camundongos , Camundongos Transgênicos , Células Estromais/citologia , Células Estromais/imunologia , Simportadores/genética , Timo/imunologiaRESUMO
BACKGROUND: Intravenous oxycodone has been used as an adjunct to anesthetic agents. This study aimed to assess the optimal dose of intravenous oxycodone for the attenuation of the hemodynamic responses to laryngoscopy and endotracheal intubation. METHODS: A prospective, randomized, double-blind study was conducted. Ninety-five patients were randomly divided into 5 groups based on the oxycodone dose: 0, 0.05, 0.1, 0.15, 0.2âmg/kg. After administering the assigned dose of intravenous oxycodone, anesthesia was induced with thiopental. Heart rate (HR) and blood pressure (BP) were measured at baseline, before intubation, and 1, 2, and 3âminutes after intubation. The percentage increase of BP was calculated as (highest BP after intubationâ-âbaseline BP)/baseline BPâ×â100 (%). The percentage increase of HR was calculated in same formula as above. Hypertension was defined as a 15% increase of systolic BP from baseline, and probit analysis was conducted. RESULTS: Hemodynamic data from 86 patients were analyzed. The percentage increase of mean arterial pressure after intubation in groups 0.05, 0.1, 0.15, and 0.2 was significantly different from that in the control (Pâ<â0.001). For HR, the percentage increase was lower than control group when oxycodone was same or more than 0.1âmg/kg (Pâ<â0.05). Using probit analysis, the 95% effective dose (ED95) for preventing hypertension was 0.159âmg/kg (95% confidence interval [CI], 0.122-0.243). In addition, ED50 was 0.020âmg/kg (95% CI, -0.037 to 0.049). However, oxycodone was not effective for maintaining the HR in our study dosage. There were no significant differences in the incidence of hypotension during induction between groups. CONCLUSIONS: Using 0.1âmg/kg of intravenous oxycodone is sufficient to attenuate the increase of BP and HR during induction period in healthy patients. The ED95, which was 0.159âmg/kg, can be useful to adjust the dosage of IV oxycodone for maintain stable BP during induction of general anesthesia.
Assuntos
Hemodinâmica/efeitos dos fármacos , Intubação Intratraqueal , Entorpecentes/administração & dosagem , Oxicodona/administração & dosagem , Administração Intravenosa , Adulto , Anestésicos Intravenosos , Feminino , Humanos , Laringoscopia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tiopental , Adulto JovemRESUMO
PURPOSE: The purpose of this study was to investigate the effect of diabetes mellitus on primary total hip arthroplasty by comparing the clinical outcomes of patients diagnosed to have diabetes mellitus before the operation with those without diabetes. MATERIALS AND METHODS: A total 413 patients who underwent unilateral cementless total hip arthroplasty from June 2006 to May 2009 were recruited and divided into diabetic and non-diabetic groups. The comparative analysis between the two groups was made. We evaluated Harris hip score, postoperative complications such as wound problem, surgical site infection, other medical complication and length of stay in hospital as clinical parameters. Radiographic evaluations were also included to determine loosening, dislocation and osteolysis. RESULTS: Patients with diabetes had an increased incidence of orthopaedic complications including surgical site infection and mortality, but other medical complications were not increased in diabetic patients. All complications after primary total hip arthroplasty were associated with diabetes mellitus, but the degree of diabetes was not associated with complications. CONCLUSION: Diabetes mellitus increases incidence of orthopaedic complications, particularly deep infection, after cementless primary total hip arthroplasty.
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PURPOSE: The purpose of this study was to document results of a less invasive technique of open wedge proximal tibial osteotomy (PTO) for the varus knee in young adults using an intramedullary tibial nail. MATERIALS AND METHODS: We prospectively studied 24 knees in 16 young patients with varus knee deformity. The mean follow-up was 54 months (range, 36 to 107 months) and the mean age of patients at the time of operation was 25.8 years (range, 18 to 40 years). The open wedge PTO was performed below tibial tuberosity using a percutaneous multiple drill-hole technique. Conventional intramedullary tibial nail was used for fixation without bone graft. Radiographic evaluations were made using mechanical alignment (MA), posterior tibial slope angle, and Insall-Salvati ratio. Union time, loss of correction, implant failure, and associated complications were also investigated. RESULTS: The mean MA was significantly changed from -9.7° preoperatively to 1.1° at the final follow-up (p<0.001). There was no significant change in the proximal tibial anatomy and patellar height. All patients achieved radiographic bony union at an average of 3.1 months without loss of correction. The only complication was knee pain due to nail prominence in 3 patients. CONCLUSIONS: Radiographic evaluation indicated that PTO using an intramedullary tibial nail leads to significant improvement in radiographic parameters without changes in posterior tibial slope or patellar height. We found that this technique could be a less invasive and effective alternative for correction of the varus knee in young adults.
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Compartment syndrome after total knee arthroplasty (TKA) is a rare complication. Because of its rarity, it may be overlooked and misdiagnosed as peroneal nerve palsy or deep vein thrombosis. This misdiagnosis could have a profound impact on the patient's outcome. We report a case of a 77-year-old female who developed unilateral compartment syndrome in the calf after staged bilateral TKA at an outside clinic. The patient presented with medical complications related to compartment syndrome: rhabdomyolysis and myoglobinuria, which caused acute renal failure. Thus, we performed late fasciotomy one week after symptom onset to debride necrotic tissue and salvage the compartment. In the discussion section, we will discuss risk factors for compartment syndrome after TKA, results of late fasciotomy and other indications for surgical treatment of compartment syndrome.
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PURPOSE: Because evasion of tumor suppression is a critical step in cancer development, cancer cells have developed a variety of mechanisms to circumvent the influence of tumor suppressive pathways. Thus, genes that negatively regulate tumor suppressors could be considered novel types of oncogenes such as Bmi-1 repressing p16Ink4a and inhibiting p53 and were found to be frequently up-regulated in a variety of cancers. p38 mitogen-activated protein kinase (MAPK), which reportedly plays a crucial role as a tumor suppressor, is activated in number of lung adenocarcinomas, which is seemingly at odds with its role as a tumor suppressor. METHODS: We examined 10 lung adenocarcinomas and corresponding normal tissues and determined the expression levels of a variety of tumor suppressor proteins through real-time polymerase chain reaction and immunohistochemistry and measured p38 MAPK activity by immunoblotting or immunohistochemistry analysis. In the in vitro cellular model, p38 activation by H-Ras and consequent senescence induction was achieved through retro-viral gene transduction. Similarly, the suppression of p16Ink4a by Bmi-1 after the introduction of H-Ras was achieved through transient transfection with cationic liposome. RESULTS: We detected several lung adenocarcinomas that were positive for activated p38 MAPK but evidenced reduced levels of p16Ink4a expression. The suppression of p16Ink4a occurred in parallel with an increase in Bmi-1 and/or p16Ink4a promoter hypermethylation. Consistent with these observations, the H-Ras-stimulated induction of p16Ink4a was suppressed significantly through the coexpression of Bmi-1 in vitro. DISCUSSION: These results demonstrate that the suppression of p16Ink4a by either the induction of Bmi-1 or the hypermethylation of p16Ink4 may be an important step in avoiding tumor surveillance by p38 MAPK during the development of lung cancer.