The infant kidney is more vulnerable to infections than the adult kidney. It is common that acute pyelonephritis (APN) during infancy and early childhood manifests growth retardation of kidney, ultimately leading to chronic renal failure. However, little is known about the pathogenesis of renal growth retardation in APN in youth. To understand the mechanism underlying the cortical lesions, urinary tract infection was induced in infant rats. To induce ascending APN, saline solution containing Escherichia coli (ATCC No. 25922) 107 bacteria/ml was infused into the bladder through the 16 gage silicone cannula in three-week-old weaning Sprague Dawley rats (weight 50~60 g, n=66). In the normal control group (n=20), saline was infused. Experimental groups were divided according to the treatment into the APN group (APN without any treatment, n=23) and TRX group (APN with ceftriaxone treatment, n=23). After performing the histopathologic examination, including inflammatory score, fibrosis score, and tubular atrophy score, we measured the apoptosis index in the tubular cells of noninflammatory cortical area at post-infection week 1 and 3 by the in situ TUNEL method. Kidney weight was significantly decreased in the APN group compared with the normal group at postinfection week 1 and 3. In the APN group, tubulointerstitial inflammation with heavy neutrophilic infiltration was found mainly in the upper and lower poles of the kidney in both the first and third week groups. Fibrosis was dominant in the third week of the APN group. However, inflammation and fibrosis were not significantly improved by TRX treatment. The apoptotic index of tubular cells was significantly increased in noninflammatory cortical area in the first week of both APN and TRX groups. It decreased near the normal control value in the third week. TGF-beta1 protein expression was localized in the inflammatory area. There was no TGF-beta1 expression in the tubules of the noninflammatory area. These findings suggest that renal growth retardation in experimentally induced APN in infant rats is related not only with the inflammatory reaction itself but also with the increased apoptosis of tubular cells in noninflammatory area. Ceftriaxone alone does not eliminate the inflammation nor prevent growth retardation effectively.
Adolescent ; Adult ; Animals ; Apoptosis* ; Atrophy ; Catheters ; Ceftriaxone ; Escherichia coli ; Fibrosis ; Humans ; In Situ Nick-End Labeling ; Infant* ; Inflammation ; Kidney ; Kidney Failure, Chronic ; Neutrophils ; Pyelonephritis* ; Rats* ; Rats, Sprague-Dawley ; Silicones ; Sodium Chloride ; Transforming Growth Factor beta1 ; Urinary Bladder ; Urinary Tract Infections ; Weaning

Hypercholesterolemia has been regarded as a major risk factor of coronary heart disease(CHD). CHD is increasing in recent years among Koreans due to westernization of lifestyle and dietary behaviors. In the United States, implementation of the National Cholesterol Education Program(NCEP) had resulted 40% decline in mortality from CHD. This study was designed to evaluate the effect of medical nutrition therapy on serum lipid levels and discuss the effective nutrition education contents. Thirty outpatients(Male 40%, female 60%) with hypercholesterolemia were educated by medical nutrition therapy(MNT) protocol. At first visit and after three months of MNT, we assessed serum lipid profile, body weight and surveyed general characteristics, lifestyle and food habits through questionnaire. After 12 weeks of MNT, there were significant reductions in serum cholesterol and low-density lipoprotein cholesterol(LDL-C). Foods habits and lifestyle were changed to the desirable patterns. These results indicate that lipid profile is improved by changes of dietary behaviors and lifestyle. Especially in case of obesity, cholesterol lowering effect of MNT was more powerful. Consequently, MNT is effective on reduction of serum lipids by behavior change in hypercholesterolemic patients.
Body Weight ; Cholesterol ; Education ; Female ; Food Habits* ; Heart ; Humans ; Hypercholesterolemia ; Life Style ; Lipoproteins ; Mortality ; Nutrition Therapy* ; Obesity ; Surveys and Questionnaires ; Risk Factors ; United States

OBJECTIVES: This study aims to evaluate the size-dependent toxicity of spherical silver nanoparticles (Ag NPs) to an endemic benthic organism, Glyptotendipes tokunagai. METHODS: Ag nanoparticles of three nominal sizes (50, 100, and 150 nm) capped with polyvinyl pyrrolidone (PVP-Ag NPs) were used. Their physicochemical properties, acute toxicity (48 hours), and bioaccumulation were measured using third instar larvae of G. tokunagai. RESULTS: The aggregation and dissolution of PVP-Ag NPs increased with exposure time and concentration, respectively, particularly for 50 nm PVP-Ag NPs. However, the dissolved concentration of Ag ions was not significant compared with the median lethal concentration value for AgNO3 (3.51 mg/L). The acute toxicity of PVP-Ag NPs was highest for the smallest particles (50 nm), whereas bioaccumulation was greatest for the largest particles (150 nm). However, larger PVP-Ag NPs were absorbed and excreted rapidly, resulting in shorter stays in G. tokunagai than the smaller ones. CONCLUSIONS: The size of PVP-Ag NPs significantly affects their acute toxicity to G. tokunagai. In particular, smaller PVP-Ag NPs have a higher solubility and stay longer in the body of G. tokunagai, resulting in higher toxicity than larger PVP-Ag NPs.
Chironomidae ; Ions ; Larva ; Nanoparticles* ; Polyvinyls ; Silver* ; Solubility

OBJECTIVES: This study aims to evaluate the size-dependent toxicity of spherical silver nanoparticles (Ag NPs) to an endemic benthic organism, Glyptotendipes tokunagai. METHODS: Ag nanoparticles of three nominal sizes (50, 100, and 150 nm) capped with polyvinyl pyrrolidone (PVP-Ag NPs) were used. Their physicochemical properties, acute toxicity (48 hours), and bioaccumulation were measured using third instar larvae of G. tokunagai. RESULTS: The aggregation and dissolution of PVP-Ag NPs increased with exposure time and concentration, respectively, particularly for 50 nm PVP-Ag NPs. However, the dissolved concentration of Ag ions was not significant compared with the median lethal concentration value for AgNO3 (3.51 mg/L). The acute toxicity of PVP-Ag NPs was highest for the smallest particles (50 nm), whereas bioaccumulation was greatest for the largest particles (150 nm). However, larger PVP-Ag NPs were absorbed and excreted rapidly, resulting in shorter stays in G. tokunagai than the smaller ones. CONCLUSIONS: The size of PVP-Ag NPs significantly affects their acute toxicity to G. tokunagai. In particular, smaller PVP-Ag NPs have a higher solubility and stay longer in the body of G. tokunagai, resulting in higher toxicity than larger PVP-Ag NPs.
Chironomidae ; Ions ; Larva ; Nanoparticles* ; Polyvinyls ; Silver* ; Solubility