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91.
92.

Background and Purpose

The anti‐inflammatory and immunomodulatory effects of macrolides include the ability to decrease mucus secretion and inhibit inflammatory mediators in chronic rhinosinusitis. Nevertheless, their mechanisms of action remain to be determined. Here we have investigated the effects of macrolide antibiotics (clarithromycin, azithromycin and josamycin; representating the 14‐, 15‐ and 16‐membered macrolides) on endogenous steroids in human sinonasal epithelial cells and mouse nasal mucosa.

Experimental Approach

The effects of macrolides on the expression of steroid‐converting enzymes [11β‐hydroxysteroid dehydrogenase (11β‐HSD1 and 11β‐HSD2)], steroid‐synthesizing enzymes (3β‐HSD, CYP21, CYP11B1 and CYP11A1) and cortisol levels were assessed in cultured human epithelial cells. In control and adrenalectomized mice , these enzymes and corticosterone levels were evaluated in nasal mucosa and serum after administration of macrolides.

Key Results

The expression levels of 3β‐HSD, CYP21, 11β‐HSD1 and CYP11B1 increased in human epithelial cells treated with clarithromycin and azithromycin, whereas the expression levels of 11β‐HSD2 and CYP11A1 were not affected. Josamycin had no effects on the expression of these enzymes. Cortisol levels increased in epithelial cells treated with clarithromycin or azithromycin. The expression of 3β‐HSD, CYP11A1, CYP21, CYP11B1 and 11β‐HSD1 was upregulated in nasal mucosa of mice treated with clarithromycin or azithromycin, but not in adrenalectomized mice.

Conclusions and Implications

This study provides evidence that 14‐ and 15‐membered macrolide antibiotics may affect the expression of steroid‐synthesizing and steroid‐converting enzymes in human sinonasal epithelial cells and mouse nasal mucosa, increasing the endogenous cortisol levels in sinonasal mucosa.

Abbreviations

11β‐HSD1
11β‐hydroxysteroid dehydrogenase 1
11β‐HSD2
11β‐hydroxysteroid dehydrogenase 2
3β‐HSD
3β‐hydroxysteroid dehydrogenase
CYP21A1
cytochrome P450, family 21, subfamily A, polypeptide 1
CYP11B1
cytochrome P450, family 11, subfamily B, polypeptide 1
CYP11A1
cytochrome P450, family 11, subfamily A, polypeptide 1
CRS
chronic rhinosinusitis
PBS‐T
phosphate‐buffered saline‐Tween 20
PF
915275, N‐(6‐amino‐2‐pyridinyl)‐4''‐cyano‐[1,1''‐biphenyl]‐4‐sulfonamide
siRNA
small interfering RNA
  相似文献   
93.
In January 2014, an outbreak of infection with highly pathogenic avian influenza (HPAI) A(H5N8) virus began on a duck farm in South Korea and spread to other poultry farms nearby. During this outbreak, many sick or dead wild birds were found around habitats frequented by migratory birds. To determine the causes of death, we examined 771 wild bird carcasses and identified HPAI A(H5N8) virus in 167. Gross and histologic lesions were observed in pancreas, lung, brain, and kidney of Baikal teals, bean geese, and whooper swans but not mallard ducks. Such lesions are consistent with lethal HPAI A(H5N8) virus infection. However, some HPAI-positive birds had died of gunshot wounds, peritonitis, or agrochemical poisoning rather than virus infection. These findings suggest that susceptibility to HPAI A(H5N8) virus varies among species of migratory birds and that asymptomatic migratory birds could be carriers of this virus.  相似文献   
94.
Medication use trends among patients with type 2 diabetes from 2015 to 2019 were investigated in relation to the clinical group-specific recommendations from the 2018 American Diabetes Association (ADA)/European Association for the Study of Diabetes (EASD) consensus report. Data were drawn from a large health insurance claims database representing Commercial (total patient-year count: 2,379,704) and Medicare (total patient-year count: 845,823) insurance programmes (IBM® MarketScan®). The utilization of sodium-glucose co-transporter-2 inhibitors or glucagon-like peptide-1 receptor agonists increased over time but was lower in the Medicare cohort in every year evaluated. Patients diagnosed with obesity received recommended therapies at higher rates than those without obesity. Differences were more modest between those with versus without atherosclerotic cardiovascular disease (ASCVD) or chronic kidney disease, with greater treatment adoption in those without ASCVD in the Medicare cohort. Utilization of recommended treatments was paradoxically lower in those with versus without heart failure, and worse in the Medicare than in the Commercial cohort. Utilization of sulphonylureas was not different in those with versus without severe hypoglycaemia history. In conclusion, utilization of therapies recommended in the guidelines is increasing overall, which is not preferentially guided by ADA/EASD-defined clinical groups, and there exists a persistent gap in utilization between Commercial and Medicare populations.  相似文献   
95.
In the Far East, hepatic resection is the definitive treatment for complicated intrahepatic stones (IHS). However, many investigators have reported that the associated intrahepatic biliary stricture is the main cause of treatment failure. A retrospective comparative study was undertaken to clarify the long-term efficacy of hepatic resection for treatment of IHS and to investigate the clinical significance of intrahepatic biliary stricture in treatment failure after hepatic resection performed in 44 patients with symptomatic IHS. The patients were divided into two study groups: group A, with intrahepatic biliary stricture (n = 28) and group B, without stricture (n = 16). Residual or recurrent stones, recurrence of intrahepatic biliary stricture, late cholangitis, and final outcomes were analyzed and compared statistically between the two groups. The patients were followed up for a median duration of 65 months after hepatectomy. The overall incidence of residual or recurrent stones was 36% and 11%, respectively, in groups A and B. The initial treatment failure rate was 50% in group A and 31% in group B. Intrahepatic biliary stricture recurred in 46% of patients in group A, while none of the group B patients had biliary stricture recurrence (P = 0.001). More than two-thirds of the restrictures in group A were identified at the primary site. The incidence of late cholangitis was higher in group A (54%) than in group B (6%) (P = 0.002). Three-quarters of the patients with cholangitis in group A had severe cholangitis, that was recurrent, and related to stones and strictures (n = 11). They and 2 asymptomatic patients in group B required secondary procedures done at a median of 12 months after hepatectomy. Final outcomes after hepatectomy with or without secondary management were good in 80%, fair in 16%, and poor in 4% of our 44 patients. Most recurrent cholangitis after hepatectomy in patients with IHS was related to recurrent intrahepatic ductal strictures. Therefore, to be effective, hepatic resection should include the strictured duct. However, with hepatectomy alone it is difficult to clear the IHS or relieve the ductal strictures completely, particularly in patients with bilateral IHS, so perioperative team approaches that include both radiologic and cholangioscopic interventions should be combined for the effective management of IHS.  相似文献   
96.
Chun BC  Bae SC 《Lupus》2005,14(8):635-638
The rates of mortality and cancer have not been compared between Korean systemic lupus erythematosus (SLE) patients and the general population. The objective of this study was to compare the observed mortality and cancer incidence rates of SLE patients with the expected age-, sex- and calendar-matched incidence rates of a comparable general control population. This study included 466 SLE patients who were in the Hanyang Lupus Cohort, Seoul and we excluded the males from the analyses because the number of males was too small to expect any incidence of cancer or death. We used the national female mortality rates from 1992 to 2001 as recorded by the Korean National Statistical Office as the standard mortality rates, and the Seoul Cancer Registry data as the standard cancer incidence rate. Ten of the females in our study died, giving a crude mortality rate of 596.0/100 000 person-years (PY) and a standardized mortality ratio (SMR) of 3.02. The crude cancer incidence was 179.3/100 000 PYand the standard incidence ratio was 1.04. These results demonstrate that the SMR is significantly higher in SLE patients than in the general population, whereas the incidence of cancer is the same in these two groups.  相似文献   
97.
Background/aims The possibility of proximal lesion without distal polyps is a weak point of sigmoidoscopic colon cancer screening, but the clinical significance of distal findings for advanced proximal neoplasm (APN) is uncertain. The aim of this study was to assess the significance of a distal finding as a predictor of APN. Materials and methods Asymptomatic patients ≥50 years old were enrolled from among patients who underwent polypectomy at 11 tertiary medical centers during the Korean Association for the Study of Intestinal Disease prospective study conducted between July 2003 and March 2004. Polyps located distal to the splenic flexure were defined as distal polyps. An advanced neoplasm was defined as a polyp of ≥10 mm in size, and/or with villous features, and/or with high-grade dysplasia, or invasive cancer. Age, gender, and distal polyp size, appearance, and histology were analyzed as risk factors of APN. The sensitivity and positive predictive value of distal polyps for APN were calculated. Results Data from 826 patients were analyzed. Mean patient age was 60.1 years (range 50–86), and 71.3% were men. APN was found in 98 patients, and 45 (45.9%) patients had no distal polyps. Risk factors of APN were a male gender, distal polyp size, and an advanced distal neoplasm. Sensitivities of a distal polyp of ≥10 mm and of an advanced distal neoplasm for APN were both 38.8% with positive predictive values of 13.3 and 14.4%, respectively. Conclusions Although distal colon findings were found to be helpful for predicting APN in asymptomatic patients aged ≥50 years, APN without distal polyps requires careful consideration.  相似文献   
98.
BACKGROUND AND AIM: Although insulin resistance is often considered the link between obesity and non-alcoholic fatty liver disease (NAFLD), the role of insulin resistance, independent of obesity, as a NAFLD risk factor in non-obese men has been less well established. Systemic inflammation may be accompanied by insulin resistance in healthy subjects. The goal of the present study was to examine if insulin resistance and systemic inflammatory markers are independent predictors of NAFLD in non-obese men. METHODS: The authors conducted a cross-sectional survey of 120 patients with NAFLD and 240 controls matched by age and body mass index. Controls had no evidence of alcohol abuse, hepatitis B or C, obesity, or previous history of diabetes, fasting hyperglycemia or hypertension. Diagnosis of NAFLD was based on an elevated alanine aminotransferase level and sonographic evidence of a fatty liver. Insulin resistance was determined using a homeostasis model assessment (HOMA-IR). RESULTS: The age-adjusted risk of developing NAFLD was strongly associated with the elevated levels in measurements of uric acid, fasting blood sugar, triglycerides, apolipoprotein B, C-reactive protein (CRP) and HOMA-IR, and decreased levels of high density lipoprotein cholesterol and apolipoprotein A-I. Multivariate analysis based on univariate analysis indicated that an increase in CRP (odds ratio [OR] = 1.37; 95% confidence interval [CI]: 1.06-1.77) per 1 SD (1.48 mg/L) and HOMA-IR (OR = 2.28; 95% CI: 1.67-3.11) per 1 SD (0.63) were independent risk factors for NAFLD. CONCLUSION: Insulin resistance and systemic inflammatory response are of key importance for inducing NAFLD, particularly in apparently healthy non-obese men.  相似文献   
99.
Leiomyosarcoma is an uncommon tumor which arises from various sites including uterus, stomach, retroperitoneum, superficial soft tissues, bladder, kidney, and lung. Primary hepatic leiomyosarcoma is a very rare tumor and fewer than 70 cases of primary hepatic leiomyosarcoma have been reported since the first publication in Japan. And there was only one case report of cutaneous metastasis from hepatic leiomyosarcoma. We recently experienced a case of primary hepatic leiomyosarcoma presenting as subcutaneous palpable mass. Herein we report this case with a review of literatures.  相似文献   
100.

Background

The changes in insulin resistance and insulin secretion and their association with changes in glucose regulation status in Asians with prediabetes remain uncertain.

Materials and Methods

We included Korean adults (aged 20-79 years) with prediabetes who underwent routine medical check-ups at a mean interval of 5 years. Prediabetes was defined as fasting plasma glucose (FPG) 5.6-6.9 mmol/l or HbA1c 5.7-6.4% (39-46 mmol/mol). Insulin resistance (HOMA-IR) and beta-cell function (HOMA-%B) indices were assessed by homeostasis model assessment. Incident diabetes was defined as FPG ≥ 7.0 mmol/l, HbA1c ≥ 6.5% (48 mmol/mol), or initiation of antidiabetic medications.

Results

Among the 7,208 participants with prediabetes, 4,410 (61.2%) remained as prediabetes (control group), 2,123 (29.5%) reverted to normal glucose regulation (regressors), and 675 (9.4%) progressed to type 2 diabetes (progressors) after 5 years. Compared with the control group, the progressors had higher baseline HOMA-IR (2.48 ± 1.45 versus 2.06 ± 1.20, P < 0.001), but similar baseline HOMA-%B (74.6 ± 47.6 versus 73.1 ± 41.4, P=0.68). By contrast, the regressors had lower baseline HOMA-IR (1.98 ± 1.14 versus 2.06 ± 1.20, P = 0.035) but higher baseline HOMA-%B (77.4 ± 43.1 versus 73.1 ± 41.4, P = 0.001). After 5 years, the progressors showed a 31% increase in HOMA-IR (2.48 ± 1.45 versus 3.24 ± 2.10, P < 0.001) and 15% decrease in HOMA-%B (74.6 ± 47.6 versus 63.8 ± 40.4, P < 0.001), whereas the regressors showed 29% decrease in HOMA-IR (1.98 ± 1.14 versus 1.41 ± 0.78, P < 0.001) and 4% increase in HOMA-%B (77.4 ± 43.1 versus 80.2 ± 47.9, P = 0.010).

Conclusions

Although increase in insulin resistance and decrease in beta-cell function both contributed to the progression to type 2 diabetes from prediabetes, longitudinal change in insulin resistance was the predominant factor in Koreans.  相似文献   
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