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31.
Pyruvate is included in the energy production of the heart muscle and is metabolized into lactate, alanine, and CO(2) in equilibrium with HCO(3) (-). The aim of this study was to evaluate the feasibility of using (13)C hyperpolarization enhanced MRI to monitor pyruvate metabolism in the heart during an ischemic episode. The left circumflex artery of pigs (4 months, male, 29-34 kg) was occluded for 15 or 45 min followed by 2 hr of reperfusion. Pigs were examined by (13)C chemical shift imaging following intravenous injection of 1-(13)C pyruvate. (13)C chemical shift MR imaging was used in order to visualize the local concentrations of the metabolites. After a 15-min occlusion (no infarct) the bicarbonate signal level in the affected area was reduced (25-44%) compared with the normal myocardium. Alanine signal level was normal. After a 45-min occlusion (infarction) the bicarbonate signal was almost absent (0.2-11%) and the alanine signal was reduced (27-51%). Due to image-folding artifacts the data obtained for lactate were inconclusive. These studies demonstrate that cardiac metabolic imaging with hyperpolarized 1-(13)C-pyruvate is feasible. The changes in concentrations of the metabolites within a minute after injection can be detected and metabolic maps constructed.  相似文献   
32.
OBJECTIVE: The purpose of the study was to compare in prospective randomized fashion a manually sutured esophagogastric anastomosis in the neck and a stapled in the chest after esophageal resection and gastric tube reconstruction. SUMMARY BACKGROUND DATA: Despite the fact that all reconstructions after esophagectomy will result in a cervical or a thoracic anastomosis, controversy still exists as to the optimal site for the anastomosis. In uncontrolled studies, both neck and chest anastomoses have been advocated. The only reported randomized study is difficult to evaluate because of varying routes of the substitute and different anastomotic techniques within the groups. The reported high failure rate of stapled anastomoses in the neck and the fact that most surgeons prefer to suture cervical anastomoses made us choose this technique for anastomosis in the neck. Our routine and the preference of most surgeons to staple high thoracic anastomoses became decisive for type of thoracic anastomoses. METHODS: Between May 9, 1990 and February 5, 1996, 83 patients undergoing esophageal resection were prospectively randomized to receive an esophagogastric anastomosis in the neck (41 patients) or an esophagogastric anastomosis in the chest (42 patients). To evaluate selection bias, patients undergoing esophageal resection during the same period but not randomized (n = 29) were also followed and compared with those in the study (n = 83). Objective measurements of anastomotic level and diameter were assessed with an endoscope and balloon catheter 3, 6, and 12 months after surgery. The long-term survival rates were compared with the log-rank test. RESULTS: Two patients (1.8%) died in hospital, and the remaining 110 patients were followed until death or for a minimum of 60 months. The genuine 5-year survival rate was 29% for chest anastomoses and 30% for neck anastomoses. The overall leakage rate was 1.8% (2 cases of 112) with no relation to mortality or anastomotic method. All patients in the randomized group had tumor-free proximal and distal resection lines, but 1 patient in the nonrandomized group had tumor infiltrates in the proximal resection margin. At 3, 6, and 12 months after operation, there was no difference in anastomotic diameter between the esophagogastric anastomosis in the neck and in the thorax (P = 0.771), and both increased with time (P = 0.004, ANOVA repeated measures). Body weight development was the same in the two groups. With similar results in randomized and nonrandomized patients, study bias was eliminated. CONCLUSIONS: When performed in a standardized way, neck and chest anastomoses after esophageal resection are equally safe. The additional esophageal resection of 5 cm in the neck group did not increase tumor removal and survival; on the other hand, it did not adversely influence morbidity, anastomotic diameter, or eating as reflected by body weight development.  相似文献   
33.
Dyslipidaemia exists frequently after renal transplantation (RTx) and promotes atherosclerosis. In this study, we examined the association between daily intake of nutrients and serum lipids after paediatric RTx. We studied 45 children with acceptably functioning kidney grafts and adequately completed food records at a median age of 10.6 years (range 4.3–17.2 years), a median 5.2 years (range 1.0–11.0) after RTx, and 178 healthy controls at a median age of 9.0 years (range 3.2–18.7 years). Serum total cholesterol (TC), triglyceride, and apolipoprotein B concentrations were higher in the RTx patients than in the controls (P < 0.001), despite similar dietary intakes of saturated and polyunsaturated fats, and cholesterol. Both the RTx patients and controls ingested a low amount of polyunsaturated fats [mean (SD) percent of total calories (E%) 4.8 (1.3) and 4.6 (1.5), respectively] and an excessive amount of saturated fats [mean (SD) E% 14.4 (2.4) and 14.1 (2.8), respectively]. In multiple regression analyses, dietary fibre was negatively associated with serum TC concentration. The standard deviation score for body mass index was negatively associated with serum concentration of high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein diameter, and positively with serum triglyceride concentration. In addition, dietary total fat intake was positively associated with serum HDL-C. In conclusion, the higher prevalence of dyslipidaemia in our paediatric RTx patients than in the controls was not explained by the diet. However, the type of fat consumed implicates the counselling for a healthier dietary lifestyle, with an increase in the ingestion of polyunsaturated fats and a decrease in that of saturated fats.  相似文献   
34.
35.
We present a case (41 years old pregnant female) with epithelioid sarcoma arising in the left external auditory canal. On immunohistochemistry, the tumor cell diffusely expressed cytokeratins and showed patchy expression of ERG and CD34. The neoplastic cells demonstrated uniform loss of INI1-expression. Epithelioid sarcoma arising in the external auditory canal is rare. Awareness that ES may rarely arise at unusual sites is of critical importance in order to apply a broad enough panel in the immunohistochemical study, so a misdiagnosis of carcinoma can be avoided.  相似文献   
36.
OBJECTIVE: The aim of the study was to evaluate the change over time of cartilage defects, subchondral lesions and meniscal abnormalities of the knee using magnetic resonance (MR) imaging with a 2-year interval in patients with chronic knee pain. DESIGN: In the format of a prospective study of early osteoarthritis (OA), the signal knee (most painful at the inclusion in the study 1990) in 47 individuals, 25 women and 22 men (aged 41-57 years, median 50), with chronic knee pain, with or without radiographically determined knee OA, were examined using MR imaging on a 1.0 T imager with a 2-year interval (median 25 months, range 21-30). Cartilage defects, subchondral lesions and meniscal abnormalities were recorded and compared in blind between the examinations. RESULTS: Five new cartilage defects and eight subchondral lesions appeared during the 2-year interval. Seven defects and seven subchondral lesions disappeared during the same time. Thirty-two out of 93 cartilage defects (34%) and 19 out of 32 subchondral lesions (59%) displayed an increase or a decrease in size over time. A meniscal abnormality appeared in three locations, and disappeared in none. In 14 out of 54 locations (26%) with a meniscal abnormality an increase or a decrease of the abnormality was recorded over time and no abnormality decreased. CONCLUSIONS: After the 2 years of observation it was possible to register, using MR imaging, the appearance, increase, decrease and disappearance of cartilage defects, subchondral lesions and meniscal abnormalities in middle-aged people with chronic knee pain. This has to be considered in studies of the natural course of knee OA as well as in studies of the intraarticular effect of pharmacological treatment aiming at cartilage repair or protection.  相似文献   
37.
A review of the current literature reveals no systematic analyses of the results of surgical correction of spinal deformity after pediatric organ transplantation. We therefore evaluated clinical and radiographic outcomes of spinal deformity correction after solid organ transplantation in childhood and adolescence. All 211 cases of heart, liver, and kidney transplantations performed in children in our country were reviewed. Six patients had undergone surgical correction of spinal deformity at a mean age 14.6 (range 12–17) years. Clinical data of the patients were evaluated. Radiographs of the whole spine were taken preoperatively, immediately after, at 2-year, and final follow-up visits. The Scoliosis Research Society (SRS) questionnaire was completed and a physical examination was performed at the final follow-up visit. The mean follow-up after spinal surgery was 4.9 years (range 2–7.6 years). Four patients developed scoliosis after organ transplantation without any evidence of scoliosis prior to organ transplantation. One patient with congenital scoliosis was operated on after kidney transplantation. One boy had osteoporosis and severe local kyphosis due to vertebral compression fractures. Four patients underwent anterior and posterior surgery, two posterior only. The mean preoperative Cobb angle of the thoracic curve was 54° (range 42–69°) in the patients with scoliosis. The postoperative values were 30° (26–38°) immediately after instrumentation and 39° (34–42°) at the final follow-up visit. The patient with vertebral compression fractures and progressive kyphosis had 70° curve before surgery, 23° immediately after the operation, and 60° at the final check up. The mean total score on the SRS questionnaire was 95.5 (range 90–101). There is a relatively high incidence (2.8%) of spinal deformities needing operative treatment after solid organ transplantation. Possible etiologies for spinal deformities are growth disturbance and muscle weakness due to the basic disease. The other important factors are related to immunosupressive medication, especially glucocorticoids needed after transplantation. Primary correction of these deformities was satisfactory, but during follow-up, a certain amount of recurrence of the curves was evident. Poor bone quality may explain some of the loss of correction.  相似文献   
38.
The need for maintenance dialysis for infants is rare, but peritoneal dialysis has been the modality of choice in cases of end-stage renal failure, for technical reasons. Problems include higher mortality rates and an inferior long-term outcome compared with that in older children. Also, no internationally accepted guidelines exist for dialysis in infants. Many children on maintenance peritoneal dialysis in Finland have congenital nephrotic syndrome of the Finnish type (NPHS1), and dialysis is started during infancy. In this commentary we discuss our practice of performing peritoneal dialysis in infants and experiences gathered from the literature.  相似文献   
39.
BACKGROUND: Hypercholesterolemia after organ transplantation is common. Previously, we observed higher serum total cholesterol (TC) concentrations in our pediatric kidney than liver or heart transplant recipients. To find an explanation to the observed difference, our kidney recipients' cholesterol synthesis and absorption efficiency was compared to those of liver and heart recipients. METHODS: Serum noncholesterol sterol ratios (10 x mmol to the mol of TC, surrogate estimates of hepatic cholesterol synthesis and intestinal absorption) were studied in 50 pediatric kidney, 25 liver and 12 heart transplant recipients without diabetes or cholestasis, and in 29 controls. RESULTS: The kidney recipients had lower Delta-cholesterol (P=0.031), similar lathosterol and higher desmosterol ratios (markers of cholesterol synthesis) (P=0.020), and similar campesterol and sitosterol ratios (markers of cholesterol absorption) when compared to the controls. The liver recipients had lower campesterol ratios than the kidney recipients and controls (P=0.002). Glomerular filtration rates were not associated with the ratios of noncholesterol sterols. Multivariate analysis showed markers of cholesterol synthesis to be lower and absorption to be higher in the kidney than the liver or the heart transplant recipients. Weight-adjusted dosages of immunosuppressive agents were associated with some ratios of noncholesterol sterols and cholestanol though these varied between the transplant recipient groups. CONCLUSIONS: Serum TC concentration in kidney recipients was not significantly associated with absorption efficiency or synthesis of cholesterol, though kidney transplantation was associated with low synthesis and high absorption efficiency of cholesterol. Immunosuppressive therapy with cyclosporine and methylprednisolone may modulate absorption efficiency and synthesis of cholesterol.  相似文献   
40.
BACKGROUND: It is unclear whether the prevalence of chronic low back pain is higher in chronic whiplash patients than in the general population. In a population-based study, we evaluated the prevalence of chronic low back pain in individuals with chronic neck pain of traumatic and non-traumatic origin, with special emphasis on whiplash injury. SUBJECTS AND METHODS: Additional questions concerning the patient's experience of neck and low back pain were added to the questionnaire of the MONICA health survey. 4,415 subjects aged 25-64 years were randomly selected from a geographically well-defined area in northern Sweden. RESULTS: The prevalences of chronic low back pain and chronic neck pain were 16% and 17%, respectively. 51% of subjects had both back and neck pain. Of the patients with neck pain, one quarter had a history of neck injury, which was related to whiplash injury in almost one-half of the cases. The prevalence of chronic low back pain in individuals with chronic non-traumatic neck pain was 53%, and it was 48% in those with chronic neck pain and a history of neck trauma. There was no difference in the prevalence of chronic low back pain between whiplash injury and other types of neck trauma. Confounding factors such as sex, age, marital status, BMI, smoking status and level of education were not significantly different between traumatic and non-traumatic groups. INTERPRETATION: Independently of traumatic or non-traumatic origin of the symptoms, the prevalence of chronic low back pain is 3 times higher in individuals with chronic neck pain than in the general population. Causes other than a history of neck trauma, such as chronic muskuloskeletal pain syndromes, may be important in evaluation of these cases.  相似文献   
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