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41.
Aging is characterized by progressive loss of cognitive and memory functions as well as decrease in physical activities. In the present study, a human neural stem cell line (F3 NSC) over-expressing choline acetyltransferase (F3.ChAT), an enzyme responsible for acetylcholine synthesis, was generated and transplanted in the brain of 18-month-old male ICR mice. Four weeks post-transplantation, neurobehavioral functions, expression of ChAT enzyme, production of acetylcholine and neurotrophic factors, and expression of cholinergic nervous system markers in transplanted animals were investigated. F3.ChAT NSCs markedly improved both the cognitive function and physical activity of aging animals, in parallel with the elevation of brain acetylcholine level. Transplanted F3 and F3.ChAT cells were found to differentiate into neurons and astrocytes, and to produce ChAT proteins. Transplantation of the stem cells increased brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), enhanced expression of Trk B, and restored host microtubule-associated protein 2 and cholinergic nervous system. The results demonstrate that human NSCs over-expressing ChAT improve cognitive function and physical activity of aging mice, not only by producing ACh directly but also by restoring cholinergic neuronal integrity, which might be mediated by neurotrophins BDNF and NGF.  相似文献   
42.
43.

Purpose

To investigate the effect of pretreatment with intravenous nicorandil on the incidence of contrast-induced nephropathy (CIN) in patients with renal dysfunction undergoing coronary angiography.

Materials and Methods

This randomized controlled multicenter study enrolled a total of 166 patients (nicorandil n=81; control n=85) with an estimated glomerular filtration rate <60 mL/min. Nicorandil 12 mg dissolved in 100 mL of 0.9% saline was administered intravenously for 30 minutes just prior to coronary angiography in the nicorandil group. The same volume of only saline was given to the control group. The primary end-point was the incidence of CIN, defined as >0.5 mg/dL increase or >25% rise in serum creatinine (SCr) concentration within 48 hours of contrast exposure compared to baseline.

Results

The final analysis included 149 patients (nicorandil n=73; control n=76). The baseline characteristics and the total volume of the used contrast (Iodixanol, 125.6±69.1 mL vs. 126.9±74.6 mL, p=0.916) were similar between the two groups. The incidence of CIN also did not differ between the nicorandil and control groups (6.8% vs. 6.6%, p=0.794). There was no difference between the two groups in the relative change in SCr from baseline to peak level within 48 hours after coronary angiography (-1.58±24.07% vs. 0.96±17.49%, p=0.464), although the nicorandil group showed less absolute change in SCr than the control group (-0.01±0.43 mg/mL vs. 0.02±0.31 mg/mL, p=0.005).

Conclusion

Prophylactic intravenous infusion of nicorandil did not decrease the incidence of CIN in patients with renal dysfunction undergoing coronary angiography.  相似文献   
44.

Purpose

After esophagectomy and gastric reconstruction for esophageal cancer, patients suffer from various symptoms that can detract from quality of life. Endoscopy is a useful diagnostic tool for evaluating patients after esophagectomy. This observational study was performed to investigate the correlation between symptoms and endoscopic findings one year after esophageal surgery and to assess the clinical usefulness of one-year endoscopic follow-up.

Materials and Methods

From 2001 to 2008, 162 patients who underwent esophagectomy with gastric reconstruction were endoscopically examined one year after operation.

Results

Patients suffered from the following symptoms: nocturnal cough (n=10), regurgitation (n=7), cervical heartburn (n=3), lump sensation (n=2), dysphagia (n=20) and odynophagia (n=22). Eighty-five (52.5%) patients had abnormal findings on endoscopic examination. Twelve (7.4%) patients had reflux esophagitis, and 37 (22.8%) patients had an anastomotic stricture. Only stricture-related symptoms were correlated with the finding of anastomotic strictures (p<0.001). Two patients had recurrences at the anastomotic sites, and four patients had regional lymph node recurrences with gastric conduit invasion visualized by endoscopy. Newly-developed malignancies in the esophageal remnant or hypopharynx that were not detected by clinical symptoms and imaging studies were reported in two patients.

Conclusion

One year after esophagectomy, endoscopic findings were not correlated with clinical symptoms, except those related to stricture. Routine endoscopic follow-up is a useful tool for identifying latent functional and oncological lesions.  相似文献   
45.
BackgroundChronic hepatitis B is the most common cause of liver cirrhosis in South Korea. However, alcoholic liver disease has shown an increasing trend. Although the clinical implications surrounding liver cirrhosis have been changing over the years, few studies have recently examined cirrhosis epidemiology. Therefore, we aimed to investigate changes in liver cirrhosis etiology and severity in Korea.MethodsWe retrospectively reviewed 16,888 records of cirrhotic patients from six tertiary hospitals in Korea from 2008 to 2017. Continuous and non-continuous variables were processed via linear and Poisson regression, expressed as beta (B) coefficients and as exponentiated values of coefficients (Exp[B]), respectively.ResultsChronic hepatitis B showed a decreasing trend (Exp[B] = 0.975, P < 0.001), whereas alcohol showed an increasing trend (Exp[B] = 1.013, P = 0.003), occupying the most common etiology in 2017. The Child-Turcotte-Pugh (CTP) score and decompensated liver cirrhosis prevalence did not change over the 10-year period. The incidence of variceal bleeding, severe ascites, hepatic encephalopathy, and spontaneous bacterial peritonitis significantly decreased from 12.3% to 7.7%, 7.8% to 4.1%, 1.0% to 0.5%, and 1.9% to 1.1%, respectively (P < 0.05 for all). In the subgroup analysis, the chronic hepatitis B group showed improving CTP scores (B = −0.025, P < 0.001) and decreasing decompensated liver cirrhosis rates (Exp[B] = 0.977, P = 0.016), whereas the alcohol group demonstrated increasing CTP class C (Exp[B] = 1.031, P = 0.005) and model for end-stage liver disease scores (B = 0.081, P = 0.005) over 10 years.ConclusionThe chronic hepatitis B group exhibited improved results, whereas the alcohol group still presented poor liver functions and outcomes. Future national policies and systematic approaches addressing the incidence, prevention, and treatment of alcoholic liver cirrhosis are indispensable.  相似文献   
46.
Background and PurposeReportedly 30–50% of patients being treated for chronic illnesses do not adhere to their medication regimen. We assessed the impact of a nurse-led education program for caregivers of Korean de novo Alzheimer''s disease patients who had newly been prescribed donepezil.MethodsThis multicenter study analyzed 93 participants in a caregiver education group and 92 participants in a caregiver no-education group. At every visit up to the end of the study (1 year), caregivers in the education group were given educational brochures regarding Alzheimer''s disease and the efficacy and adverse events of donepezil treatment. The primary endpoint was the discontinuation rate of donepezil treatment during the 1-year observation period. The secondary endpoints included the effect of education on compliance with donepezil treatment assessed at each visit using a clinician rating scale (CRS) and visual analog scale (VAS), and changes from baseline in cognitive assessment tests.ResultsThe donepezil discontinuation rates at 1 year were 5.38% (5/93) and 6.52% (6/92) in the caregiver education and no-education groups, respectively (p=0.742). No significant between-group differences in donepezil compliance rates on the CRS and VAS were observed, but significant changes were observed in some cognitive tests from baseline to the end of the study.ConclusionsCaregiver education had no significant effect on treatment discontinuation, but this may have been due to the low severity of cognitive impairment among the included population at baseline. In addition, the low discontinuation rates meant that no significant difference in treatment compliance was observed.  相似文献   
47.
Background and PurposeWe investigated 18F-fluorodeoxyglucose (FDG) uptake levels in the lumbar vertebrae, liver, and spleen of stroke patients with carotid atherosclerosis.MethodsThis study analyzed acute ischemic stroke patients with carotid atherosclerosis who underwent whole-body FDG positron-emission tomography between October 2015 and January 2017. FDG uptake in the lumbar vertebrae, liver, and spleen was measured and compared between stroke patients and control subjects without stroke history. Multivariate linear regression analysis was performed to identify independent factors related to FDG uptake in the proximal internal carotid artery (ICA).ResultsTwenty stroke patients aged 75.1±9.0 years (mean±standard deviation; 10 females) and 20 control subjects aged 62.9±10.7 years (6 females) were included. In comparison with the control group, the stroke group showed significantly higher FDG uptake in the proximal ICA (1.16±0.26 vs. 0.87±0.19, p<0.01), but significantly lower FDG uptake in the lumbar vertebrae (1.09±0.26 vs. 1.38±0.38, p=0.007) and liver (1.71±0.30 vs. 2.01±0.34, p=0.005). Multivariate linear regression analysis showed that the lumbar FDG uptake was negatively correlated with FDG uptake in the proximal ICA (standardized coefficient=-0.367, p=0.013) after adjusting for age and hypertension.ConclusionsStroke patients showed decreased FDG uptake in the lumbar vertebrae. Further studies are warranted to evaluate the pathophysiological link between cerebral atherosclerosis and bone.  相似文献   
48.
49.
The association of body mass index, smoking, and blood pressure, which are related to the three well-established risk factors of renal cell carcinoma, and survival in patients with renal cell carcinoma is not much studied. Our objective was to evaluate this association. A cohort of 1,036 patients with low stage (pT1 and pT2) renal cell carcinoma who underwent radical or partial nephrectomy were enrolled. We retrospectively reviewed medical records and collected survival data. The body mass index, smoking status, and blood pressure at the time of surgery were recorded. Patients were grouped according to their obesity grade, smoking status, and hypertension stage. Survival analysis showed a significant decrease in overall (P = 0.001) and cancer-specific survival (P < 0.001) with being underweight, with no differences of smoking status or perioperative blood pressure. On multivariate analysis, perioperative blood pressure ≥ 160/100 mmHg (HR, 2.642; 95% CI, 1.221-5.720) and being underweight (HR, 4.320; 95% CI, 1.557-11.984) were independent predictors of overall and cancer-specific mortality, respectively. Therefore, it is concluded that being underweight and perioperative blood pressure ≥ 160/100 mmHg negatively affect cancer-specific and overall survival, respectively, while smoking status does not influence survivals in patients with renal cell carcinoma.  相似文献   
50.
Type 1 citrullinemia (CTLN1) often presents as a hyperammonemic encephalopathy in the neonatal period, but it can also develop in the late-infantile period and in adults. In addition, some patients can be identified in the presymptomatic period by neonatal or family member screening. In this study, twenty Korean patients with CTLN1 (19 families) were examined; fourteen patients with neonatal-onset, three with late-onset, and three that were identified presymptomatically. The 13 patients with hyperammonemic encephalopathy received continuous venovenous hemofiltration (CVVH) or peritoneal dialysis (PD). Although the hyperammonemia was relieved more effectively in the six patients on CVVH than the seven on PD, most of these patients suffered from severe neurologic deficits. Recurrent hyperammonemic episodes (7 pts, 35%), recurrent and reversible acute hepatic dysfunction (5 pts, 25%), and focal cerebral infarction (2 pts, 10%) were noted. The neonates with hyperammonemic encephalopathy had extensive brain injuries at the onset of hyperammonemia, followed by encephalomalacia and brain atrophy at quite an early age. Genetic testing for the ASS1 gene revealed a different mutation spectrum from those of other ethnicities; Three common mutations, c.421-2A > G (37.8%), c.1128-6_1188dup67 (18.9%), and p.Gly324Ser (16.2%), accounted for 73% of the mutations. The poor outcome was expected in patients with the peak ammonia level at onset over 600 μmol/L, whose proportion was higher in the neonatal presentation group than in the presymptomatic/late presentation group. Our findings add to the current understanding of the ethnic diversity of CTLN1 from both clinical and genetic perspectives.  相似文献   
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