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51.
BACKGROUND AND PURPOSE: The relevance of cavernous carotid artery calcification on unenhanced CT scans of the brain has recently been investigated against the backdrop of the widespread implementation of coronary artery calcification scoring. We sought to determine whether the degree of cavernous carotid artery calcification correlated with scores of white matter hyperintensity seen on MR images. In so doing, we sought to establish a relative risk for future stroke on the grade of carotid calcification. METHODS: Neuroradiologic findings in 187 patients who underwent CT and MR imaging examinations within 1 month of each other were retrospectively reviewed. The degree of circumferential calcification and thickness of calcification were graded for the cavernous carotid arteries on the basis of CT findings. Using the scale developed by the Cardiovascular Health Study, the white matter was graded for degree of disease on the basis of MR findings. Correlation tests and regression analyses were performed to determine the impact of age, race, and sex on results. RESULTS: Although the cavernous carotid calcification scores and the MR imaging white matter scores showed good correlation (P <.001), the effect was mediated by age. With age factored in as a covariant, no correlation was shown between CT calcification scores and MR imaging white matter scores. Sex had no effect, but African American study participants had worse MR imaging white matter scores than did white participants. CONCLUSION: After adjusting for age, cavernous carotid calcification grades and MR imaging white matter scores do not show a significant correlation. The relative risk for future stroke cannot be predicted from cavernous carotid calcifications.  相似文献   
52.
Worldwide, there is an epidemic of obesity and overweight, with two-thirds of Americans affected. A strong association exists between excessive body weight and nonalcoholic fatty liver disease (NAFLD), the most common etiology of abnormal liver function tests. Nonalcoholic fatty liver disease is a spectrum of liver disease, from a "bland" fatty infiltration to chronic hepatitis (nonalcoholic steatohepatitis or NASH), that can result in cirrhosis and organ failure. With the increasing prevalence of obesity in the world, the proportion of people affected by NAFLD is only expected to be parallel. Although primarily noted in obese individuals, NAFLD has also been associated with a number of surgical procedures, metabolic conditions, and medications. NASH is commonly underdiagnosed as most affected patients are symptom free, and routine screening is not performed. Noninvasive diagnostic testing is not sensitive in diagnosis or staging the severity of disease. Fatty infiltration and oxidative injury to the hepatocytes are believed to be the major factors behind the progression of disease from simple fatty infiltration of the liver to chronic hepatitis. Understanding the inflammatory pathways involved in NASH is a subject of extensive research. Currently, few proven treatment options exist, and controlled weight reduction is the only safe modality recommended for treatment of NASH.  相似文献   
53.
The syntheses of neocryptolepine derivatives containing an amino acid or a dipeptide at the C-9 position and their evaluation for antitumor activity in vitro and in vivo are reported. To establish the influence of an amino acid or a peptide on the physicochemical properties of 5H-indolo[2,3-b]quinoline (DiMIQ), lipophilic and hemolytic properties were investigated. Most of the compounds displayed a high antiproliferative activity in vitro and strongly inhibited growth of tumor in mice compared to cyclophosphamide. The attachment of the hydrophilic amino acid or the peptide to the hydrophobic DiMIQ increased its hydrophilic properties and decreased its hemolytic activity. The glycylglycine conjugate (7a) was the most promising derivative. It strongly inhibited the growth of the tumor in mice (at dose 50 mg kg(-1) day(-1) it inhibited the tumor growth by 46-63% on days 11-16 and by 29-43% on days 18-23) and significantly decreased hemolytic activity and lowered the in vivo toxicity compared to DiMIQ.  相似文献   
54.
Patients with end-stage kidney disease, treated with renal transplantation, are at increased risk of cardio-vascular disease (CVD) and cardio-vascular mortality. They are also characterized by an atherogenic dyslipidemia. Alterations of the fatty acids (FA) profile contribute to increased cardio-vascular risk in the general population. In the current study we test the hypothesis that kidney transplantation is associated with ab-normalities in FA profile. FA profile was analysed by gas chromatography–mass spectrometry in 198 renal transplant recipients, and 48 control subjects. The most profound differences between renal transplant patients and controls were related to the content of branched chain FA, monounsaturated FA, and n-6 polyunsaturated FA, respectively. The FA profile significantly separated the patients from the controls in the principal component analysis (PCA). The abnormalities of FA profile showed a tendency for normalization in long-term kidney recipients, as compared to patients with recent transplants. The n-3 PUFA content demonstrated a strong inverse association with the presence of inflammation. Most profound alterations of the FA profile were observed in patients with impaired graft function (glomerular filtration rate < 45 mL/min). The study demonstrated significant disorders of the FA profile in kidney transplant recipients, that might contribute to cardio-vascular risk in this vulnerable patient population.  相似文献   
55.

Introduction

Endotracheal intubation (ETI) using a Macintosh laryngoscope (MAC) requires the head to be positioned in a modified Jackson position, slightly reclined and elevated. Intubation of trauma patients with an injured neck or spine is therefore difficult, since the neck usually cannot be turned or is already immobilized in order to prevent further injury. The iGEL supraglottic airway seems optimal for such conditions due to its blind insertion without the need of a modified Jackson position.

Methods

Prospective, randomized, crossover study in 46 paramedics. Participants performing standard intubation and blind intubation via iGEL supraglottic airway device in three airway scenarios: Scenario A – normal airway; Scenario B - manual inline cervical immobilization, performed by an independent instructor; scenario C: cervical immobilization using a standard Patriot cervical extraction collar.

Results

In Scenario A, nearly all participants performed ETI successfully both with MAC and iGEL (100% vs. 95.7%). The time to intubation (TTI) using the MAC and iGEL amounted to 19 [IQR, 18–21]s vs. 12 [IQR, 11–13]s (P < 0.001). Head extension angle as well as tooth compression were significantly better with the iGEL compared to the MAC (P < 0.001). In scenario B and C, the results with the iGEL were significantly better than with MAC for all analyzed variables (TTI, success of first intubation attempt, head extension angle, tooth compression and VAS scores).

Conclusion

We showed that blind intubation with the iGEL supraglottic airway was superior to ETI performed by paramedics in a simulated cervical immobilization scenario in a manikin in terms of success rate, time to definite tube placement, head extension angle, tooth compression, and rating.  相似文献   
56.

Background

The impact of high-quality chest compressions during CPR for the patients' outcome is undisputed, as it is essential for maintaining vital organ perfusion. The aim of our study is to compare the quality of chest compression (CC) and ventilation among the two current standard techniques with our novel “nTTT” technique in infant CPR.

Methods

In this randomized crossover, manikin trial, participants performed CCs using three techniques in a randomized sequence: standard two finger technique (TFT); standard two thumb technique (TTHT), and the ‘new two-thumb technique’ (nTTT). The novel method of CCs in an infant consists in using two thumbs directed at the angle of 90° to the chest while closing the fingers of both hands in a fist.

Results

Median depth compression using the distinct chest compression techniques varied and amounted to 26 [IQR, 25–28] mm for TFT, and 39 [IQR, 39–39] mm for TTHT as well as for nTTT. Best percentage of fully released compressions were received using TFT (100[100 ? 100] %), then in the case of nTTT (99[98–100] %), and the worst in situation where TTHT (18[14–19] %). was used. The fastest chest compression rate was achieved with TFT (134[IQR, 129–135]/min) and the slowest when using nTTT (109 [IQR, 105–111]/min).

Conclusions

We found that our new nTTT technique's performance, in terms of compression depth, hands-off time, and ventilation quality, is comparable to the current standards. Based on our findings of this initial manikin study, the nTTT technique is superior to TFT in many of parameters that are vital to a quality chest compression during pediatric CPR.  相似文献   
57.
BACKGROUND: New tools to identify genotype-phenotype interactions need to be described and implemented. The aim of this study was to identify correlation between the risk originating from gene variation and diet-dependent development of insulin resistance. METHODS: Insulin output in terms of area under the curve after an oral glucose tolerance test (AUC Ins OGTT) and lipid tolerance tests (AUC Ins OLTT) were measured in 167 overweight/obese patients. Estimation of the 18 common gene polymorphisms for obesity risk and standard phenotyping were performed. RESULTS: Insulin output (AUC Ins OGTT) correlated strongly between both insulin treatments across the whole group. However, within the genotype sub-groups, correlation was lower or did not exist. Using a nutrient-induced insulin output ratio (NIOR), calculated as AUC Ins OLTT/AUC Ins OGTT, values ranged from 0.42 to 5.83 and correlated significantly with body mass index (BMI) and leptin, but not with age, gender, waist-to-hip ratio (WHR) and homeostasis model assessment of insulin resistance (HOMA-IR) or plasma adiponectin. High NIOR was found in a subgroup of carriers of rare allelic variants of genes characteristic for poorer tolerance to lipids in the diet. Low NIOR values were found within a sub-group with rare genetic variants regulating carbohydrate metabolism. Thus, the new insulin index NIOR may distinguish gene variant carriers into groups of glucose- or lipid-sensitive phenotypes. CONCLUSIONS: We suggest that the OLTT/OGTT insulin output ratio (NIOR) may be predictive for identifying individuals who are phenotypically susceptible to insulin resistance in response to high fat or carbohydrate in their habitual diet.  相似文献   
58.
59.

Objective

To describe the factors associated with survival 20 years after endovascular treatment of an abdominal aortic aneurysm (AAA) in a single center.

Methods

Prospective cohort of asymptomatic patients with an infrarenal aortic aneurysm treated with a bifurcated endovascular graft (Talent) between June 1997 and August 2008. Cox proportional hazard multivariable regression was used for analysis of independent risk factors for survival. Kaplan-Meier curves were done with the long-rank test. P < .05 was considered significant.

Results

We followed 229 patients, 184 without an endoleak and 45 with an endoleak. Ages ranged between 52 and 89 years, and the mean diameter of the aneurysm was 59.51 ± 14.6 mm. Implantation of the endovascular graft was possible in 99% of the patients. The 30-day mortality rate was 3.4%. In the Cox regression, age <73 years (hazard ratio [HR], 0.42; 95% confidence interval [CI], 0.27-0.64), aneurysm size ≤55 mm (HR, 0.62; 95% CI, 0.40-0.95), male sex (HR, 0.17; 95% CI, 0.05-0.52), American Society of Anesthesiologists surgical risk category I and II vs III and IV (HR, 0.51; 95% CI, 0.34-0.75), and aneurysm size reduction ≤3 mm after treatment (HR, 2.23; 95% CI, 1.11-4.51) were significantly correlated with the survival of the patients followed in this long-term case series.

Conclusions

This 20-year prospective cohort included patients with an AAA treated with a bifurcated endovascular graft (Talent) at a university hospital in Brazil. This study supports that sex, age, aneurysm size, aneurysm size reduction, and American Society of Anesthesiologists surgical risk category are significantly correlated with patient survival after endovascular treatment of the AAA.  相似文献   
60.

Background

Bariatric surgery contributes to the improvement in glucose metabolism that may be related to a postoperative increase in serum bile acids (BAs). Three commonly used types of bariatric procedures, laparoscopic sleeve gastrectomy (LSG) (without creation of a bile loop), Roux-en-Y gastric bypass (RYGB), and omega-loop gastric bypass (OLGB) (with creation of shorter 100–150 cm and longer 200–280 cm bile loops, respectively), differ in their effects on glycemic control. The aim of the study was to compare the effects of various bariatric procedures on serum BA concentration and glucose homeostasis.

Methods

Serum BAs in 26 obese patients were determined by liquid chromatography-mass spectrometry prior to bariatric surgery, as well as 4 days and 3 months thereafter.

Results

Four days after the surgery, serum concentrations of BAs in LSG and OLGB groups were similar as prior to the procedure, and a slight decrease in serum BAs was observed in the RYGB group. Serum BA level in the LSG group remained unchanged also at 3 months after the surgery, whereas a significant 0.5- and 3-fold increase in this parameter was noted in the RYGB and OLGB groups, respectively. Serum concentration of BAs correlated positively with the length of the bile loop (R?=?0.47, p?<?0.05).

Conclusion

The evident improvement of glycemic control observed 3 months after OLGB might be associated with a postoperative increase in serum BAs, resulting from their better absorption from the longer bile loop. However, the changes in serum BAs probably had little or no impact on insulin sensitivity improvement at 4 days post-surgery.
  相似文献   
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