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101.

Background

Liver dysfunction in children dependent on parenteral nutrition (PN) is well established, and the extent of hyperbilirubinemia has been shown to correlate with morbidity and mortality. The aim of this study was to assess whether increasing provisions of enteral nutrition can improve PN-associated hyperbilirubinemia over time.

Methods

A retrospective review was conducted on infants in our institution's Short Bowel Syndrome Clinic from 1999 to 2004. Inclusion criteria included PN duration more than 1 month, serum direct bilirubin more than 3 mg/dL while on PN, and tolerance of full enteral nutrition with eventual discontinuation of PN. Paired t tests were used for statistical analyses.

Results

Twelve infants were identified with a PN duration of 5 ± 1 months. Five patients underwent liver biopsy while on PN, and histological evidence of cholestasis was found on all specimens. Peak total and direct bilirubin levels were 10.5 ± 1.9 and 7.0 ± 1.6 mg/dL, respectively, and occurred at time of PN discontinuation. Only 2 patients had improvement in serum bilirubin levels before initiation of full enteral nutrition. After initiation of full enteral nutrition and discontinuation of PN, all patients achieved permanent normalization of bilirubin levels by 4 months (P < .05) after a 1-month plateau phase. Alkaline phosphatase levels approached reference range within this time but were not significant.

Conclusion

These data demonstrate for the first time that although PN-dependent infants can achieve normalization of marked hyperbilirubinemia with enteral nutrition, the improvement in liver function usually begins only after full enteral nutrition is tolerated and PN is withdrawn. These findings support the aggressive weaning of PN to enteral nutrition in infants with short bowel syndrome.  相似文献   
102.
Vitamin D (25(OH)D) increases the efficiency of intestinal calcium absorption. Low levels of serum calcium stimulate the secretion of parathyroid hormone (PTH), which maintains serum calcium levels at the expense of increased bone turnover, bone loss and increased risk of fractures. We studied the association between 25(OH)D and PTH levels, and their associations with bone mineral density (BMD), bone loss, and prevalence of hip fractures in 615 community-dwelling postmenopausal aged 50–97 years. Mean level of 25(OH)D and PTH were 102.0 nmol/l±35.0 nmol/l and 49.4 ng/l±23.2 nmol/l, respectively; 49% of women were current hormone therapy users. The overall prevalence of vitamin D insufficiency (25(OH)D<50 nmol/l) was 2%, and prevalence of high PTH levels (>65 ng/l) was 17.4%. In multiple linear regression analyses hip BMD was negatively and independently associated with PTH levels ( p =0.04), and positively and independently associated with 25(OH)D levels ( p =0.03). There were only 23 women (3.7%) who experienced a hip fracture. In age-adjusted analyses there were no significant differences of 25(OH)D and PTH levels by hip fracture status. Across the entire range of values, the overall correlation between 25(OH)D and PTH was moderate ( r =–0.20). However, after the threshold vitamin D level of 120 nmol/l, all PTH values were below 65 ng/l. Further studies are necessary to identify the optimal vitamin D levels necessary to prevent secondary hyperparathyroidism.  相似文献   
103.
Diffusion tensor magnetic resonance imaging (DTI) provides data concerning water diffusion in the spinal cord, from which white matter tracts may be inferred, and connectivity between spinal cord segments may be determined. We evaluated this potential application by imaging spinal cords from normal adult rats and rats that received cervical lateral funiculotomies, disrupting the rubrospinal tract (RST). Vitrogen and fibroblasts were transplanted into the surgical lesion at time of injury in order to fill the cavity. At 10 weeks, animals were sacrificed; the spinal cords were dissected out and then imaged in a 9.4-Tesla magnet. DTI tractography demonstrated the disruption of the rubrospinal tract axons while indicating which axon tracts were preserved. Additionally, DTI imaging could identify the orientation of glial processes in the gray matter adjacent to the site of injury. In the injured animals, reactive astrocytes in adjacent gray matter appeared to orient themselves perpendicular to white matter tracts. In summary, DTI identified not only white matter disruption following injury, but could distinguish the orientation of the accompanying glial scar.  相似文献   
104.
Background  A premise of this study was that different psychological processes would predict the initiation and maintenance of weight loss after surgery for morbid obesity. Our aim was to examine whether more favorable preoperative expectations of psychosocial outcomes predict weight loss in the first year after laparoscopic adjustable gastric banding (LAGB) and whether postoperative satisfaction with these outcomes predicts weight maintenance in the second year after the operation. Methods  Six months before and 1 year after surgery, the “Obesity Psychosocial State Questionnaire” was filled out by 91 patients (77 female, 14 male, mean age 45 ± 9 years, mean preoperative body mass index 47 ± 6 kg/m2). We evaluated the preoperative outcome expectations and the postoperative satisfaction for the seven domains of psychosocial and physical functioning of this questionnaire, as well as the correlations between these scores and both weight loss and weight maintenance. Results  Patients showed high satisfaction with psychosocial outcomes after LAGB in all seven domains (p < 0.001), even though the improvement was less than expected in five of the domains (p ≤ 0.01). While weight loss 1 year after the operation was related to satisfaction with psychosocial outcomes (p ≤ 0.05), preoperative expectations were not related to weight loss in the first year after surgery, and satisfaction with the outcomes was not related to weight maintenance in the second year after surgery. Conclusion  Our study suggests that surgically induced effects of weight loss and weight maintenance are achieved independently of the patient’s preoperative expectations of and postoperative satisfaction with the psychosocial outcomes.  相似文献   
105.
Orchiectomized (ORX) rats were used to examine the extent to which their increased bone resorption and decreased bone density might relate to increases in RANKL, an essential cytokine for bone resorption.Serum testosterone declined by > 95% in ORX rats 1 and 2 weeks after surgery (p < 0.05 versus sham controls), with no observed changes in serum RANKL. In contrast, RANKL in bone marrow plasma and bone marrow cell extracts was significantly increased (by  100%) 1 and 2 weeks after ORX. Regression analyses of ORX and sham controls revealed a significant inverse correlation between testosterone and RANKL levels measured in marrow cell extracts (R = − 0.58), while marrow plasma RANKL correlated positively with marrow plasma TRACP-5b, an osteoclast marker (R = 0.63). The effects of RANKL inhibition were then studied by treating ORX rats for 6 weeks with OPG-Fc (10 mg/kg, twice/week SC) or with PBS, beginning immediately after surgery. Sham controls were treated with PBS. Vehicle-treated ORX rats showed significant deficits in BMD of the femur/tibia and lower trabecular bone volume in the distal femur (p < 0.05 versus sham). OPG-Fc treatment of ORX rats increased femur/tibia BMD and trabecular bone volume to levels that significantly exceeded values for ORX or sham controls. OPG-Fc reduced trabecular osteoclast surfaces in ORX rats by 99%, and OPG-Fc also prevented ORX-related increases in endocortical eroded surface and ORX-related reductions in periosteal bone formation rate. Micro-CT of lumbar vertebrae from OPG-Fc-treated ORX rats demonstrated significantly greater cortical and trabecular bone volume and density versus ORX-vehicle controls. In summary, ORX rats exhibited increased RANKL protein in bone marrow plasma and in bone marrow cells, with no changes in serum RANKL. Data from regression analyses were consistent with a potential role for testosterone in suppressing RANKL production in bone marrow, and also suggested that soluble RANKL in bone marrow might promote bone resorption. RANKL inhibition prevented ORX-related deficits in trabecular BMD, trabecular architecture, and periosteal bone formation while increasing cortical and trabecular bone volume and density. These results support the investigation of RANKL inhibition as a strategy for preventing bone loss associated with androgen ablation or deficiency.  相似文献   
106.
Roh HG  Kim SS  Han H  Kang HS  Moon WJ  Byun HS 《Neuroradiology》2008,50(3):237-242
Introduction Aneurysms of the posterior cerebral artery (PCA) are rare, and most of the studies reported in the literature in which the endovascular approach was applied were carried out on a limited number of patients with PCA aneurysms. We retrospectively reviewed our cases of PCA aneurysms – at various locations and of differing shapes – that received endovascular treatment and evaluated the treatment outcome. Methods From January 1996 to December 2006, 13 patients (eight females and five males) with 17 PCA aneurysms (nine fusiform and eight saccular) were treated using the endovascular approach. The age of the patients ranged from 20 to 67 years, with a mean age of 44 years. Of the 13 patients, ten presented with intracranial hemorrhage, and one patient, with a large P2 aneurysm, presented with trigeminal neuralgia; the aneurysms were asymptomatic in the remaining two patients. Results All 13 patients were successfully treated, with only one procedure-related symptomatic complication. Seven patients were treated by occlusion of the aneurysm and parent artery together; five patients, by selective embolization of the aneurysm; one patient, by partial coiling. Although infarctions were found in two patients treated with selective embolization and in three patients treated with parent artery occlusion, only one patient with a ruptured P2 aneurysm treated with parent artery occlusion developed transient amnesia as an ischemic symptom. Conclusion Posterior cerebral artery aneurysms can be treated safely with either occlusion of the aneurysm together with the PCA or with a selective coil embolization. Infarctions may occur after endovascular treatment, but they are rarely the cause of a disabling symptom.  相似文献   
107.
Fetal MRI is used with increasing frequency as an adjunct to ultrasound (US) in prenatal diagnosis. In this review, we discuss the relative value of both prenatal US and MRI in evaluating fetal and extra-fetal structures for a variety of clinical indications. Advantages and disadvantages of each imaging modality are addressed. In summary, MRI has advantages in demonstrating pathology of the brain, lungs, complex syndromes, and conditions associated with reduction of amniotic fluid. At present, US is the imaging method of choice during the first trimester, and in the diagnosis of cardiovascular abnormalities, as well as for screening. In some conditions, such as late gestational age, increased maternal body mass index, skeletal dysplasia, and metabolic disease, neither imaging method may provide sufficient diagnostic information.  相似文献   
108.
The Nd:YAG laser efficacy associated with conventional treatment for bacterial reduction has been investigated throughout literature. The purpose of this study was to evaluate the bacterial reduction after Nd:YAG laser irradiation associated with scaling and root planning in class II furcation defects in patients with chronic periodontitis. Thirty-four furcation lesions were selected from 17 subjects. The control group received conventional treatment, and the experimental group received the same treatment followed by Nd:YAG laser irradiation (100 mJ/pulse; 15 Hz; 1.5 W, 60 s, 141.5 J/cm2). Both treatments resulted in improvements of most clinical parameters. A significant reduction of colony forming unit (CFU) of total bacteria number was observed in both groups. The highest reduction was noted in the experimental group immediately after the treatment. The number of dark pigmented bacteria and the percentage of patients with Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans reduced immediately after the treatment and returned to values close to the initial ones 6 weeks after the baseline for both groups. The Nd:YAG laser associated with conventional treatment promoted significant bacterial reduction in class II furcation immediately after irradiation, although this reduction was not observed 6 weeks after the baseline.  相似文献   
109.
STUDY DESIGN: Observational, repeated measures design. OBJECTIVES: To determine the reliability of the apparent diffusion coefficient (ADC) calculated from diffusion-weighted magnetic resonance images (MRI) of the nuclear region of lumbar intervertebral discs (IVDs), to investigate the differences in the ADC based upon T2-signal intensity, and to examine the test-retest variation in these measures obtained from subjects undergoing serial, diffusion-weighted MRI scans. BACKGROUND: Impaired diffusion of water within the lumbar IVD is a central characteristic of degenerative disc disease. Diffusion-weighted MRI scans can provide quantitative estimates of water diffusion and may be useful to evaluate the physiologic effects of healing or the change in hydration related to interventions such as traction, manual therapy, or exercise on normal and degenerative lumbar IVDs. METHODS AND MEASURES: Thirty subjects underwent T2 -weighted and diffusion-weighted lumbar MRI scans. Twenty-one of these subjects underwent a second diffusion-weighted MRI scan 4 to 7 weeks after the initial scan. The ADC was calculated from midsagittal diffusion-weighted images for the IVDs of L1-2 to L5-S1. To assess reliability, repeated measures of the ADC were performed on the first 16 scans. The T2-signal of the nuclear region of each disc was classified as hyperintense, intermediate, or hypointense, and its relationship to the mean ADC of the nuclear region was determined. Test-retest variation in the ADC was described using the coefficient of variation (CV), plus or minus the width of the 95% confidence interval of the standard error of measurement (SEM). RESULTS: Intraclass correlation coefficients for estimates of intrarater and interrater reliability ranged from 0.95 to 0.99 and the SEM ranged from 0.006 to 0.026 X 10-3 mm2/s. The mean ADC was significantly greater for hyperintense IVDs compared to intermediate and hypointense IVDs. The CV plus or minus the 95% CI of the SEM between scans ranged from 9.0% to 13.6% for all discs, 6.1% to 10.1% for hyperintense discs, and 13.1% to 23.7% for intermediate discs. The prevalence of hypointense discs was too low to make meaningful judgments about their normal degree of variation over time. CONCLUSION: The ADC of the nuclear region of the lumbar IVDs may be reliably measured from diffusion-weighted images. Degenerative discs had lower mean ADC values than normal discs but demonstrated greater variation between scans. Diffusion-weighted imaging may be a useful procedure to assess change in diffusion of water in lumbar discs that occurs over time.  相似文献   
110.
Aggressive treatment of hypertension is effective in reducing both microvascular and macrovascular complications in type 2 diabetes, and target BP less than 130/85 or 130/80 mmHg are now recommended. Inhibition of renin angiotensin aldosterone system (RAAS) plays an essential role in the treatment of hypertension and diabetes-related complications. Studies focusing on renal end-points suggest that angiotensin-converting enzyme inhibitors (ACE-I) are more effective than other traditional agents in reducing the onset of clinical proteinuria in both type 1 and type 2 diabetic patients with incipient nephropathy, mainly in normotensive ones (secondary prevention). However, several small trials in type 2 diabetic patients with overt nephropathy (tertiary prevention) failed to demonstrate a specific renoprotective role for ACE-I, at variance with type 1 diabetes. Three recent large trials address the question of whether angiotensin II receptor blockers (ARB) prevent the development of clinical proteinuria or delay the progression of nephropathy in type 2 diabetes. The IRMA study showed that irbesartan is more effective than conventional therapy in preventing the development of clinical proteinuria and in favoring the regression to normoalbuminuria for comparable BP control in patients with incipient nephropathy. The IDNT and RENAAL trials showed that ARB are more effective than traditional antihypertensive therapies in reducing progression toward end-stage renal failure (ESRF) in type 2 diabetic patients with overt nephropathy independently of changes in BP. Moreover, a reduction in hospitalizations for heart failure was demonstrated for ARB-treated patients compared with placebo. Furthermore, the LIFE study showed that losartan is more effective than conventional therapy in reducing cardiovascular morbidity and mortality in a cohort of diabetic patients with hypertension and left ventricular hypertrophy. In conclusion, ARB seem to be effective in both preventing renal damage and reducing progression toward ESRF in type 2 diabetic patients. Thus, the guidelines for the prevention and treatment of diabetic nephropathy are now changed. In type 1 diabetes ACE-I are the first-choice drug; in type 2 diabetes, ARB are considered first-choice drugs in secondary prevention as well as ACE-I and have been now elected the unique first-choice drug in tertiary prevention of ESRF. Finally, ARB should be considered as the first-choice drug in cardiovascular prevention too, as well as ACE-I.  相似文献   
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