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61.
Angiotensin II (AngII) participates in the pathogenesis of kidney damage. Parathyroid hormone (PTH)-related protein (PTHrP), a vasodilator and mitogenic agent, is upregulated during renal injury. The aim of this study was to investigate the potential relation between AngII and PTHrP system in the kidney. Different methods were used to find that both rat mesangial and mouse tubuloepithelial cells express PTHrP and the type 1 PTH/PTHrP receptor (PTH1R). In these cells, AngII increased PTHrP mRNA and protein production. In contrast, PTH1R mRNA was increased in mesangial cells and downregulated in tubular cells, but its protein levels were unmodified in both cells. AT(1) antagonist, but not AT(2), abolished AngII effects on PTHrP/PTH1R. The in vivo effect of AngII was further investigated by systemic infusion (a low dose of 50 ng/kg per min) into normal rats. In controls, PTHrP immunostaining was mainly detected in renal tubules. In AngII-infused rats, PTHrP staining increased in renal tubules and appeared in the glomerulus and the renal vessels. After AngII infusion, PTHR1 staining was markedly increased in all these renal structures at day 3 but remained elevated only in tubules at day 7. The AT(1) antagonist, but not the AT(2), significantly diminished AngII-induced PTHrP and PTHR1 overexpression in the renal tissue, associated with a decrease in tubular damage and fibrosis. The results indicate that AngII regulates renal PTHrP/PTH1R system via AT(1) receptors. These findings demonstrate that PTHrP upregulation occurs in association with the mechanisms of AngII-induced kidney injury.  相似文献   
62.
BACKGROUND: Increased abdominal pressure is associated with elevations in the intracranial pressure (ICP) and impaired renal function. These adverse effects are potentially important in clinical situations such as severe abdominal trauma and laparoscopic donor nephrectomy. It was hypothesized that the secondary elevation of ICP leads to release of vasoconstrictors, which may affect renal function by decreasing the renal blood flow (RBF). We investigated the effect of laparoscopy on ICP and renal blood flow in a porcine model. MATERIALS AND METHODS: The abdominal pressure of swine (N = 5; 20-25 kg) was gradually increased from baseline to 5, 15, and 25 mm Hg by insufflation of nitrogen into the abdominal cavity. The ICP was measured using a Camino monitor, and RBF was simultaneously measured using a Transonic Doppler probe placed on the renal artery. Results were analyzed using repeated measures ANOVA and the paired t-test. RESULTS: No significant change from baseline was observed in ICP and RBF when the abdominal pressure was 5 mm Hg. However, both ICP and RBF were affected by increasing the abdominal pressure to 15 and 25 mm Hg (P = 0.035 and 0.04 for ICP and P = 0.074 and 0.034 for RBF, respectively). CONCLUSIONS: Low-pressure laparoscopy may reduce the adverse effects of pneumoperitoneum on ICP and RBF. It may be advisable to use low pressures in laparoscopic surgery, especially when changes in ICP or renal perfusion may have significant clinical implications.  相似文献   
63.
The extended brow lift: the toucan technique   总被引:1,自引:0,他引:1  
Brow ptosis is the main consequence of aging in the upper third of the face. Many methods have been described to correct it: skin excisions of the brow hairline, skin excisions of the forehead natural creases, skin trimmings of the temporal, coronal, or forehead hairline flaps, and endoscopic methods [1,15,17,18,24,26,27]. The authors created a procedure which is based on a forehead-temporal subcutaneous flap and a muscular relocation. It treats the brow ptosis and its surrounding area—temporal ptosis, upper and lower lateral eyelid ptosis, crow's feet—and at the same time improves the sclera show or ectropion. The method preserves the sideburn and the temporal hairline and can reduce the width between the temporal hairline and the lateral end of the eyebrow. The method produces maximum improvement, with high-quality scars and minimal evidence of surgery. The procedure is called "The Toucan Technique," due to the shape of the skin resection which looks like a toucan bird [11,13,14].  相似文献   
64.
BACKGROUND: We have reported that feeding type V collagen (col(V)) to lung allograft recipients induces immune tolerance that prevents acute lung allograft rejection. Repeated acute rejection is a risk factor for or associated with chronic rejection, known as bronchiolitis obliterans (BO), the leading cause of death in lung allograft recipients. The current study examines if col(V)-induced oral tolerance prevents BO. METHODS: WKY rats (RT1l) were fed either col(V) or diluent before orthotopic transplantation of F344 (RT1lvl) lung allografts. No rats received any immunosuppression. At 10 weeks posttransplantation the time to onset of BO, delayed type hypersensitivity (DTH) responses to donor antigens, and col(V) were examined. In addition, proliferative responses of recipient T lymphocytes to donor antigens, and ability of recipient antigen presenting cells to present alloantigens in lung allografts were evaluated. RESULTS: The data show that recipient rats have sustained DTH responses to donor antigens and col(V). T lymphocytes from col(V)-fed lung allograft recipients were unable to proliferate in response to donor antigens, but feeding col(V) had no effect on the presentation of donor alloantigens by recipient antigen presenting cells. All diluent fed rats developed BO, but only mild acute rejection (grade 2) was present in all rats fed col(V). Transforming growth factor (TGF)-beta production was up-regulated systemically in col(V)-fed, but not diluent fed, lung allograft recipients, and neutralizing TGF-beta [corrected] recovered the DTH response to donor antigens in col(V)-fed rats. CONCLUSIONS: Collectively these data show that col(V)-induces oral tolerance that prevents BO, and that tolerance may be mediated by systemic production of TGF-beta [corrected].  相似文献   
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67.
Treating intra-articular fractures about the osteoporotic distal humerus poses a significant challenge. The purpose of this retrospective study was to evaluate functional outcomes for distal humeral fractures treated with total elbow arthroplasty (TEA) or open reduction and internal fixation (ORIF) in a nonarthritic elderly population with osteoporosis. We reviewed the records of all women older than age 60 who had undergone surgical treatment for intraarticular distal humerus fractures (Orthopaedic Trauma Association types 13B and 13C) by 1 of 2 surgeons. Demographic and operative data were obtained, charts were reviewed, and patients were asked to have their outcomes evaluated with the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire and the Mayo Elbow Performance Index (MEPI). Twenty-two patients (23 elbows) were identified, and 2 of these (3 elbows) were excluded. Of the remaining 20 patients, 9 had undergone cemented, semiconstrained TEA as initial treatment, and 11 had undergone ORIF. These 2 groups were compared. Mean follow-up was 14.8 months (range, 6-38 months). There were no significant differences between the TEA and ORIF groups with respect to demographic factors. Final elbow range of motion was 92° flexion-extension arc (arthroplasty group) and 98° (fixation group). Two patients in the arthroplasty group and 2 in the fixation group died. For the remaining patients, mean DASH scores were 30.2 (arthroplasty) and 32.1 (fixation), and mean MEPI scores were 79 (arthroplasty) and 85 (fixation). These differences were not statistically significant. Four TEAs developed radiographic loosening by a mean of 15 months, and 1 of these underwent revision with good outcome. Ten of the 11 fractures in the fixation group healed radiographically; the 1 nonunion with collapse continued to be asymptomatic. Two patients in the fixation group underwent contracture release after union for limited elbow range of motion. Many factors come into play in the treatment of intra-articular distal humerus fractures in patients with osteoporosis. Implant selection must be based on bone quality, expected outcome, and surgeon experience. For these injuries, good outcomes may be obtained with either TEA or ORIF.  相似文献   
68.
BACKGROUND: Children with obstructive sleep apnea (OSA) have a higher rate of adverse post-extubation respiratory events, such as laryngospasm, upper airway obstruction, apnea, desaturation and/or need for re-intubation. They are overly sensitive to sedatives and narcotics. Although the etiology of OSA is primarily obstruction (mechanical or neuromuscular), a central element may contribute to OSA. Caffeine citrate has been shown to be effective in treating apnea of prematurity. This study evaluated whether the administration of caffeine benzoate to children with OSA decreases the number of children who experience adverse post-extubation respiratory events. METHODS: In a randomized, double-blind and placebo-controlled study, children with OSA scheduled for adenotonsillectomy (T&A) received either caffeine benzoate, 20 mg/kg IV, (caffeine group, n = 36) or saline (placebo group, n = 36). The primary outcome evaluated the number of children who developed adverse post-extubation respiratory events, and the secondary outcome was the incidence of those events. RESULTS: The results demonstrated the two groups differed in the number of children who developed adverse post-extubation respiratory events (p = 0.032). The overall incidence of adverse postoperative respiratory events was less in the caffeine group than the placebo group (p = 0.0196). CONCLUSION: In children with OSA scheduled for T&A, administration of caffeine benzoate, 20 mg/kg IV, decreased the number of children who developed adverse post-extubation respiratory events and decreased the overall incidence of adverse post-extubation respiratory events. PACU duration, hospital discharge time and postoperative delirium did not differ between groups.  相似文献   
69.
The Authors report on a rare case of blunt traumatic injury of the gallbladder. A careful clinical examination, an abdominal ultrasonography and a contrast material-enhanced computed tomography have a primary importance for a correct diagnosis. Laparoscopic surgery has an important diagnostic and, in selected cases, therapeutic role. In all traumatic gallbladder ruptures, after an accurate search of eventual associated injuries of other abdominal organs, cholecystectomy is considered the treatment of choice.  相似文献   
70.
Chemokines and diabetic wound healing   总被引:2,自引:0,他引:2  
Ochoa O  Torres FM  Shireman PK 《Vascular》2007,15(6):350-355
Chemokines are critical for white blood cell recruitment to injured tissues and play an important role in normal wound healing processes. In contrast, impaired wound healing in diabetic patients is accompanied by decreased early inflammatory cell infiltration but persistence of neutrophils and macrophages in the chronic, nonhealing wounds. These changes in inflammatory cell recruitment occur in conjunction with alterations in chemokine and growth factor expression. In addition to leukocyte trafficking, many different cell types, including endothelial cells, fibroblasts, and keratinocytes, produce and respond to chemokines, and these interactions are altered in diabetic wounds. Thus, the chemokine system may have both direct and inflammatory-mediated effects on many different aspects of diabetic wound healing. The potential roles of chemokines and inflammatory or immune cells in nonhealing diabetic wounds, including impairments in growth factor expression, angiogenesis, extracellular matrix formation, and reepithelialization, are examined.  相似文献   
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