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Considerable experimental evidence indicates that hyperlipidemia can induce glomerular injury. The importance of lipids in the progression of established glomerular disease has not been established and is of clinical relevance because of the frequent association of lipid abnormalities with human renal disease. In the present study, 26-week-old hyperlipidemic obese Zucker rats (OZRs) with established nephropathy were treated for a period of 18 weeks with daily injections of the cholesterol synthesis inhibitor lovastatin (4 mg/kg). Compared with control OZRs treated with vehicle, lovastatin-treated OZRs had significantly (P0.05) lower serum cholesterol and triglyceride levels throughout the treatment period. Blood pressure and urine albumin excretion in lovastatin-treated OZRs were reduced over the first 12 weeks of therapy, but increased toward the levels in the control OZRs at the end of the protocol. After 18 weeks of therapy, the incidence of glomerulosclerosis in lovastatin-treated OZRs (23.2% +/- 5.8%) was approximately half of that in vehicle-treated OZRs (44.6% +/- 7.7%) (P0.05). The reduction in glomerular injury in lovastatin-treated OZRs was not associated with changes in either glomerular area or glomerular macrophage content. In separate experiments, mesangial cells were cultured from glomeruli isolated from 26-week-old proteinuric OZRs. Lovastatin (5 to 40 mumol/L) caused a significant dose-dependent inhibition of serum-stimulated mesangial cell DNA synthesis. The inhibitory effects of lovastatin were completely prevented in the presence of exogenous mevalonate (100 mumol/L). Thus, lovastatin retarded the progression of established glomerular disease in OZRs.(ABSTRACT TRUNCATED AT 250 WORDS)

Experimental studies have demonstrated that a number of factors participate in the progression of renal disease. Systemic and glomerular hypertension have been shown to be critical factors in renal injury. Hyperlipidemia that frequently coexists with renal disease also has been suggested as an important participatory factor in nephron damage. Interestingly, both hypertension and hyperlipidemia seem to evoke glomerular growth, a factor that has also been postulated to be involved in glomerular and tubular destruction. Recently, experimental and clinical data suggest that an important interaction occurs between hyperlipidemia and hypertension. Not only do they frequently coexist, but hypertension dramatically exaggerates hyperlipidemic injury, and hyperlipidemia alters systemic and glomerular vascular production of vasoactive substances which maintain basal vascular tone. Thus, these recent observations underscore the interactive potential of the various risk factors that participate in progression of renal disease. They also suggest that multiple interventional strategies may be needed to optimally prevent progressive nephron loss.

Structural-functional relationships in type I mesangiocapillary glomerulonephritis. We quantitated glomerular and cortical interstitial structures in nine type I mesangiocapillary glomerulonephritis (MCGN) patients aged 6 to 20 years whose creatinine clearance (CCr) was 10 to 129 ml/min/1.73 m2, as compared to age-matched normal controls. Mean glomerular volume and mesangial volume fraction [Vv(mes/glom)] were increased and the percentage of the capillary endothelial circumference which was defined as filtration surface was decreased in type I MCGN patients. Vv(mes/glom) was inversely related to filtration surface area per glomerulus (r = -0.73, P < 0.05) and directly to volume density of cortical interstitium [Vv(int/cortex)] (r = +0.90; P < 0.01). Vv(mes/glom) (r = -0.87; P < 0.01), filtration surface area per glomerulus (r = +0.83; P < 0.01) and Vv(int/cortex) (r = -0.86; P < 0.01) were correlated with CCr. Thus, in type I MCGN, measures both of glomerular and of cortical interstitial structure are highly correlated with glomerular function.

Products of intracellular mevalonate metabolism are essential for cell growth and proliferation. Lovastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, blocks the formation of mevalonate and its metabolites, and has been shown to inhibit proliferation of several cell types. In vivo, lovastatin has reduced mesangial cellularity and glomerular injury in experimental renal disease. In this study, we investigated the effects of lovastatin on DNA replication and proliferation in rat glomerular mesangial cells. Growth-arrested mesangial cells were exposed to medium containing 10% fetal bovine serum to stimulate mitogenesis. Lovastatin (1-20 microM) caused a significant (P < 0.05) dose-dependent reduction in DNA synthesis ([3H]thymidine incorporation) which was completely prevented in the presence of exogenous mevalonate (100 microM). Lovastatin (1 microM) inhibited cell proliferation by 90% over a 5-d period, and this was largely overcome by added mevalonate. Exogenous low density lipoprotein (100 micrograms/ml) did not prevent lovastatin inhibition of DNA synthesis. The isoprenoid end product isopentenyl adenine (5 or 50 microM) had little effect on DNA synthesis and cell proliferation in lovastatin-blocked cells. By contrast, the isoprenoid farnesol (5 microM) largely prevented lovastatin inhibition of DNA synthesis. We conclude that mevalonate metabolism is essential for mesangial cell proliferation, possibly through the production of the isoprenoid farnesol. Moreover, the action of lovastatin to reduce experimental glomerular injury may involve a direct effect on mesangial cells.

This experience demonstrates that a bortezomib-based regimen provided effective therapy for late, refractory AMR in an adult heart transplant recipient and was well tolerated. This remarkably positive experience despite the refractory nature of the AMR episode argues strongly for continued evaluation of bortezomib use in this patient population.

The Fuel Test Loop (FTL) which is capable of an irradiation testing under a similar operating condition to those of PWR (Pressurized Water Reactor) and CANDU (CANadian Deuterium Uranium reactor) nuclear power plants has been developed and installed in HANARO, KAERI (Korea Atomic Energy Research Institute). It consists of In-Pile Section (IPS) and Out-of Pile System (OPS). The IPS, which is located inside the pool is divided into 3-parts; the in-pool pipes, the IVA (IPS Vessel Assembly) and the support structures. The test fuel is loaded inside a double wall, inner pressure vessel and outer pressure vessel, to maintain the functionality of the reactor coolant pressure boundary. The functional test and verification of the IVA were done through pressure drop, vibration, hydraulic and helium leakage tests. The brazing technique for the instrument lines has been checked for its functionality and performance. An IVA has been manufactured by a local technique and has finally been tested under high temperature and high pressure. The IVA and piping did not experience leakage, as the piping, flanges, and assemblies have been fully checked. Good data was obtained during the three cycle test which included a pressure test, pressure and temperature cycling, and constant temperature. A new concept of IVA, as easy attaching and separating test fuel at IVA will be designed thereafter.Copyright © 2010 by ASME

To further define the clinicopathologic spectrum and pathogenetic mechanism of the nephropathy associated with alpha 1-antitrypsin (A1AT) deficiency, we evaluated renal specimens from 34 patients with chronic hepatic disease, including 20 with A1AT deficiency (study patients), and correlated these findings with urinalysis evaluation. Glomerular lesions were noted in 79% (15 of 19) of A1AT patients with the PiZZ phenotype, including seven with mesangio-capillary glomerulonephritis (MPGN and focal segmental MPGN), six with mesangial proliferative glomerulonephritis (Mes GN), one with diffuse endocapillary proliferative glomerulonephritis (DPGN), and one with focal segmental mesangial proliferative glomerulonephritis with segmental necrosis (FS Nec GN). One A1AT patient with the PiMZ phenotype did not demonstrate glomerular abnormalities. Focal segmental Mes GN was found in 43% (six of 14) of patients in an age-matched group with chronic hepatic failure unrelated to A1AT deficiency. In nine study patients, glomerular pathology was noted in the presence of a normal urinalysis. Immunofluorescence studies revealed the presence of immunoproteins and the A1AT protein isoelectric forms, PiM and PiZ, in the subendothelial region of glomerular basement membranes in A1AT patients with MPGN, Mes GN, and DPGN. Our results emphasize the heterogeneity of glomerular lesions associated with A1AT deficiency and hepatic disease and the relatively high incidence of MPGN in these children. The presence of abnormal PiZ protein in the subendothelial region of the glomerular basement membrane in A1AT patients with glomerulonephritis suggests a possible role for this protein in the pathogenesis of this lesion.

A simple I-125 generating device at the research reactor, HANARO, is developed. Xenon-124 gas circulates continuously in the generator producing I-125 by neutron capture and the I-125 is adsorbed at the upper part of the generator, which is to be chemically recovered in a hot-cell. The continuous xenon circulation technology is devised by the design of the generator structure with the consideration of thermal hydraulics and neutron physics involved. A computational fluid dynamics technique is used for the conceptual design of the generator.Copyright © 2009 by ASME

7. Borkowsky W, Krasinski K, Paul D~ et al. Human immunodeficiency virus infections in infants negative for anti-H1V by enzyme-linked immunoassay. Lancet 1987;1:1168-71. 8. Consortium for Retrovirus Serology Standardization. Serologic diagnosis of human immunodeficiency virus infection by Western blot testing. JAMA 1988;260:674-8. 9. Centers for Disease Control. Classification system for human immunodeficiency virus (HIV) infection in children under 13 years of age. MMWR 1987;36:91-6. l 0. Johnson J, Davis E, Sbinaberry R, Nair P. Serologic responses to HIV infection in infants. Presented at the Fifth International Conference on AIDS, Montreal, Quebec, Canada, June 4-9, 1989. 11. Martin K, Katz B, Miller G. AIDS and antibodies to human immunodeficiency virus in children and their families. J Infect Dis 1987;155:54-9. 12. Epstein L, Boucher C, Morrison S, et al. Persistent human immunodeficiency virus type 1 antigenemia in children correlates with disease progression. Pediatrics 1988;82:919-24. 13. Ou C-Y, Kwok S, Mitchell SW, et al. DNA amplification for direct detection of HIV-1 in DNA of peripheral blood mononuclear cells. Science 1988;7:825-35. 14. Amadori A, De Rossi A, Gaguinto C, et al. In vitro production of HIV-specific antibody in children at risk of AIDS. Lancet 1988;1:852-4.

Cell envelope compounds of bacteria trigger immune and inflammatory reactions by way of chemokines/cytokines. In this study, we demonstrated that pneumococcal peptidoglycan-polysaccharides (PGPS) induced the production of interleukin (IL)-8 by way of nuclear factor (NF)-kappaB, nuclear factor interleukin (NF-IL)6, and activation protein (AP)-1 dependent mechanisms in the human bronchial epithelial cells (NL-20) in a dose- and time-dependent manner in vitro, and the mutation of either the NF-kappaB, NF-IL6, or AP-1 binding sites in the promoter of IL-8 abrogated the IL-8 transcriptional activity. In a similar way, lipopolysaccharides induced the promoter activation of IL-8 in NL-20. However, the PGPS-induced IL-8 promoter activation in rodent middle ear epithelial cells required NF-kappaB and NF-IL6 but not AP-1.

Background Blunted cultured skin fibroblast (SF) antioxidant enzyme responses to hyperglycaemia are associated with diabetic nephropathy risk. The present study explores whether this association is, at least in part, genetically determined. Methods We measured glomerular structure and SF mRNA expression for catalase and glutathione peroxidase in 21 sibling pairs concordant for type 1 diabetes. All patients had four or more (mean 21.5) years of diabetes and glomerular filtration rate>40 ml/min/1.73 m2. Thirty-four patients were normoalbuminuric, four were microalbuminuric, three were proteinuric and one was not classifiable. Heritability of patient characteristics was assessed by intra-class correlation and by a genetic variance component model. Results Mesangial fractional volume, mesangial matrix fractional volume, glomerular basement membrane width and surface density of peripheral glomerular basement membrane per glomerulus were significantly correlated in these sibling pairs. Catalase mRNA expression levels were also related and highly heritable in these sibling pairs. The association between sibship and glutathione peroxidase mRNA expression levels did not reach statistical significance. Conclusions This study suggests that SF catalase mRNA expression levels, known to be associated with diabetic nephropathy risk, are in part genetically determined.

The in vitro behavior of skin fibroblasts from patients with or without diabetic nephropathy is associated with diabetic nephropathy risk. Here we compared skin fibroblast gene expression profiles from two groups of type 1 diabetic patients: 20 with very fast (“fast-track”) versus 20 with very slow (“slow-track”) rates of development of diabetic nephropathy lesions. Gene expression profiles of skin fibroblasts grown in 25 mmol/l glucose for 36 h were assessed by Affymetrix HG-U133A GeneChips to determine the proportion of genes in a given biological pathway that were directionally consistent in their group differences. Five pathways reached statistical significance. All had significantly greater proportions of genes with higher expression levels in the fast-track group. These pathways, the first four of which are closely related and have overlapping genes, included oxidative phosphorylation (P < 0.001), electron transport system complex III (P = 0.017), citrate cycle (P = 0.037), propanoate metabolism (P = 0.044), and transcription factors (P = 0.046). These results support the concept that oxidative phosphorylation and related upstream pathways may be important in the pathogenesis of diabetic nephropathy. Whether these findings reflect inherent genetic cellular characteristics, “cell memory,” or both requires further study.

Glomerulotubular junction abnormalities, frequent in proteinuric patients with type 1 diabetes, may contribute to the progressive GFR loss in overt diabetic nephropathy. Glomerulotubular junction abnormalities were examined in patients who have type 1 diabetes with a wide range of albumin excretion rates (AER). Renal biopsies from five normoalbuminuric patients, five microalbuminuric patients, six proteinuric patients, and five control subjects were studied by light and electron microscopy. Light microscopy specimens were serially sectioned to find and classify glomerulotubular junctions. Glomerular structural parameters were estimated using stereologic methods. Glomerulotubular junction abnormalities were found in 2% of glomeruli from control and normoalbuminuric patients and in 4% of glomeruli from microalbuminuric patients. In contrast, 71% of glomeruli from proteinuric patients had glomerulotubular junction abnormalities, including five (8%) atubular glomeruli. Electron microscopy findings were typical of diabetic nephropathy. Piece-wise linear regression models with glomerular, glomerulotubular junction, and interstitial parameters as independent variables provided greater GFR (92%; P < 0.005) and AER (95%; P < 0.01) prediction than multiple regression models (81% for GFR and 72% for AER). Thus, glomerular adhesions and glomerulotubular junction abnormalities help to explain the progressive GFR loss that is associated with onset of proteinuria in type 1 diabetes. Moreover, nonlinear models provide better fit for structural-functional relationships in patients with type 1 diabetes.

Current internet is based on IPv4 protocol. However the limitation of IPv4 protocol such as a lack of address can put obstacles to continuous progress of internet. IPv6 protocol is suggested and developed as an alternative of IPv4 protocol. IPv6 protocol has many features for example the expanded addressing capability, auto-configuration mechanism, simplification of the header format, improved support for extensions and options, extensions for authentication and privacy, flow labeling capability and so on. But many security holes of IPv6 are being reported together with the features as mentioned above. This paper suggests the algorithm to solve the security hole caused by a routing header. Routing header is a kind of extension headers of IPv6 and is used by an IPv6 source to list one or more intermediate nodes to be visited on the way to a packet's destination. But routing header has the security hole that an attacker can detour the access list of security system, for example firewall, and then he can access the protected internal system by using routing header.

Altered glucose transporter expression has been implicated in the pathogenesis of diabetic nephropathy. There is increasing evidence that genetic factors convey risk of, or protection from, diabetic nephropathy and that the behaviour of cultured skin fibroblasts from type 1 diabetic patients may reflect these genetic influences. This study aimed to compare GLUT1 mRNA expression levels in skin fibroblasts from type 1 diabetic patients with either rapid ("fast-track", n=25) or slow ("slow-track", n=25) development of diabetic nephropathy and from non-diabetic normal control subjects (controls, n=25).Skin fibroblasts were cultured in Dulbecco's Modified Eagle's Medium with 25 mmol/l glucose for 36 h. Total RNA was isolated, and GLUT1 mRNA levels were estimated by microarray analysis and RT-PCR.Levels of GLUT1 mRNA expression in skin fibroblasts from "slow-track" patients were greater than those from "fast-track" patients (p=0.02), as initially detected by microarray. GLUT1 mRNA expression levels were confirmed by RT-PCR to be higher in skin fibroblasts from "slow-track" patients (4.59+/-2.04) than in those from "fast-track" patients (3.34+/-1.2, p=0.02), and were also higher than in skin fibroblasts from control subjects (3.52+/-1.66, p=0.03). There was no statistically significant difference between levels of expression in the "fast-track" patients and the control subjects.This finding is consistent with the presence of cellular protection factors against diabetic nephropathy in the "slow-track" patients. These factors could be associated with the regulation of the GLUT1 pathway and may be genetically determined.

Complete ureteral obstruction in rats rapidly leads to renal interstitial expansion and fibrosis and this process is ameliorated by concomitant angiotensin converting enzyme inhibition (ACEI). However, models of intervention initiated after unilateral ureteral obstruction (UUO) release may be more analogous to human obstructive renal disease where treatment could more reasonably follow the discovery of obstructive uropathy as compared to models where treatment is initiated at the time of experimentally induced obstruction. We studied interstitial changes in rats before and after release of UUO and examined the effect of ACEI with 200mg/L of enalapril (E) in the drinking water on these changes. Rats were sacrificed after 10 (n=10) and 20 (n=10) days (D) of UUO or 10D after release of 10D of UUO (n=18). Eleven rats received E for 10D after UUO release. Cortical interstitial volume fraction [Vv(I/C)] measured by point counting was increased at 10D (0.32 +/- 0.05) and 20D (0.41 +/- 0.05) of UUO compared to contralateral and sham-operated kidneys (both 0.05 +/- 0.01, ANOVA, p0.001). Vv(I/C) 10D after release from 10D of UUO (0.26 +/- 0.04) was lower than that of 10D of UUO (p0.05) and much lower than those with 20D of UUO (p0.001). However, rats treated with E from the time of UUO release had lower Vv(I/C) (0.21 +/- 0.07) than UUO released E untreated rats (p0.05). Release of UUO initiates regression of interstitial expansion in rats. ACEI with enalapril significantly accelerates reversal of interstitial expansion after UUO release. This could have important implications for treatment of obstructive nephropathy in humans.

Objective: Streptococcus pneumoniae is the most common pathogen in otitis media. Infection of the middle ear with S. pneumoniae potentiates development of thick effusion in the middle ear which frequently causes hearing loss and communication disorders in children. What has changed immediately in the middle ear cleft following pneumococcal infection is extensively studied and characterized but what has changed ever after remains elusive. The purpose of this study is to explore the cellular and molecular basis that remains on a longer time after acute pneucmococcal middle ear infection and potentiates development of thick effusion in the middle ear. Methods: 12 rats were intrabullarly inoculated with pneumococcus at 2.5×10 6 CFU/ear and profiles of gene expression in the middle ear were examined by cDNA microarrays in combination with reverse transcription-polymer chain reaction (RT-PCR) 6 weeks after infection while the morphologic changes in middle ear were simultaneously characterized by histopathologic techniques. Twelve rats receiving phosphate-buffered saline (PBS) served as controls. Results: it demonstrated that pneumococcus infected ears had the expression of the following genes at a high level compared to the controls: mitogenic signaling proteins (mitogen-activated protein kinase [MEK1 and MEK2], helix–loop–helix transcriptional regulators (Id3 and Id1), ion channels (sodium channel beta 1 and sodium channel 2), and mucin glycoproteins ( Muc2 and Muc5 ). The morphology demonstrated a thickened mucosa and submucosa with increased expression of macroglycoconjugates compared to the controls. Conclusion: the expression of several genes remains high even after the acute episode of pneumococcal otitis media has been resolved. The up-regulated expression of these genes may serve as the basis for the development of thick effusion and mucous cell metaplasia/hyperplasia once it is complicated with other factors such as dysfunction of the Eustachian tube.

Mucoid otitis media (MOM), one of the leading causes of acquired hearing loss in children, is characterized by mucous cell hyperplasia in the middle ear cleft associated with mucin accumulation in the middle ear cavity. The factors that stimulate mucous cell metaplasia-hyperplasia and mucin hyperproduction are poorly understood. Recent studies demonstrated that tumor necrosis factor alpha (TNF-alpha), present in human middle ear effusion, stimulated mucin production in vitro and up-regulated mucin gene expression in vivo. These findings suggest that TNF-alpha is important in the development of mucous cell metaplasia-hyperplasia. This study demonstrated that inoculation of TNF-alpha into the middle ear cavity followed by eustachian tube obstruction stimulated mucous cell metaplasia-hyperplasia in the middle ear cleft, accompanied by abundant mucin or mucin-like glycoproteins in the middle ear effusion--a phenotype of MOM in humans. This finding suggests that TNF-alpha plays a key role in the pathogenesis of MOM through induction of mucous cell metaplasia-hyperplasia and mucin production.

Otitis media with mucoid effusion, characterized by mucous cell metaplasia in the middle ear cleft and thick fluid accumulation in the middle ear cavity, is a common otological disease that frequently affects young children. Multiple factors are involved in the development of this disease, especially middle ear infection and Eustachian tube dysfunction. In this study, in order to induce otitis media with effusion in rats, we introduced a three-step method, namely inoculation of Streptococcus pneumoniae at 10(7) colony-forming units (CFU)/ear or Haemophilus influenzae at 5 x 10(7) CFU/ear into the middle ear cavity twice at 2-week intervals, followed by Eustachian tube obstruction (ETO) for 4 and 8 weeks. Animals inoculated with phosphate-buffered saline (PBS) twice in the same manner followed by ETO served as controls. Middle ear effusion and mucosa were harvested for evaluation of carbohydrate concentrations and mucous cell density, respectively. We found that rats inoculated with S. pneumoniae twice, followed by ETO at 8 weeks, yielded the highest carbohydrate concentration in middle ear effusion and the highest goblet cell density in the middle ear cavity compared to the H. influenzae and PBS groups. It is tentatively concluded that inoculation of S. pneumoniae at 10(7) CFU/ear into the middle ear cavity of rats twice at 2-week intervals, followed by ETO for 8 weeks, is a promising animal model for otitis media with mucoid effusion which may be valuable for studying the human counterpart.

The remnant kidney model, usually involving sudden removal or ablation of 1- 1 / (2) to 1-5 / (6) of renal mass, results in compensatory hypertrophy followed by hypertension, proteinuria and declining glomerular filtration rate (GFR) associated with focal (FSG) and then global glomerulosclerosis (GS) and tubulointerstitial injury (TI). Since most renal diseases involve much more gradual injury, we asked whether slow ablation (SA) produced a different natural history than fast ablation (FA).Male Münich-Wistar rats underwent heminephrectomy, 3 weeks later a second, and 3 weeks later a third heminephrectomy (SA). They were compared to littermates undergoing simultaneous removal of 1- 1 / (2) kidneys (FA) and sham operated controls (C).Three weeks after the second heminephrectomy, the SA rats had no FSG and glomerular volume (GV) was similar to that of FA rat renal tissue removed at that time. Eight weeks following the final surgical procedure (FSP), the SA and FA groups had similar blood pressures (BP) but higher than C. Albumin excretion rates (AER) were higher in SA and FA vs. C at 1 month after the FSP and, throughout most of the subsequent 5 months, greater in the SA vs. FA groups. At 24 weeks, cortical interstitial fractional volume was double C values in both the SA and FA groups. Percentage of glomeruli with FSG and size (score) of FSG lesions was much higher in SA and FA than C. Moreover, the percentage of FSG in SA (61.2+/-16%) and FSG score (1.7+/-0.7) was greater than in FA animals (35.6+/-11.9% and 0.9+/-0.4, p0.01 for each comparison). Mean GV, increased at 24 weeks in both groups over C (1.4+/-0.2 X 10(6) micro m(3)) was greater in SA (3.4+/-0.7 X 10(6) micro m(3)) than FA rats (2.1+/-0.4 X 10(6) micro m(3); p0.005).The gradual uninephrectomy in the SA group, insufficient per se to produce significant renal damage, preconditioned the residual kidney, upon further removal of another 1 / (2) kidney, to more albuminuria and FSG lesions than occurred following sudden 1- 1 / (2) nephrectomy, despite similarly elevated BP. Perhaps more time for glomerular enlargement in the SA group preconditioned the remnant kidney to accelerated injury.

This study was designed to elucidate the cellular basis of risk of or protection from nephropathy in patients with type 1 diabetes. Entry criteria included diabetes duration ofor =8 years (mean duration, 22.5 years) and glomerular filtration rate (GFR)30 ml x min(-1) x 1.73 m(-2). Patients were classified, on the basis of the estimated rate of mesangial expansion, as "fast-track" (upper quintile) or "slow-track" (lower quintile). A total of 88 patients were normoalbuminuric, 17 were microalbuminuric, and 19 were proteinuric. All three groups had increased glomerular basement membrane (GBM) width and mesangial fractional volume [Vv(Mes/glom)], with increasing severity from normoalbuminuria to microalbuminuria to proteinuria but with considerable overlap among groups. Vv(Mes/glom) (r = 0.75, P0.001) and GBM width (r = 0.63, P0.001) correlated with albumin excretion rate (AER), whereas surface density of peripheral GBM per glomerulus [Sv(PGBM/glom)] (r = 0.50, P0.001) and Vv(Mes/glom) (r = -0.48, P0.001) correlated with GFR. Vv(Mes/glom) and GBM width together explained 59% of AER variability. GFR was predicted by Sv(PGBM/glom), AER, and sex. Fast-track patients had worse glycemic control, higher AER, lower GFR, more hypertension and retinopathy, and, as expected, worse glomerular lesions than slow-track patients. Thus, there are strong relationships between glomerular structure and renal function across the spectrum of AER, but there is considerable structural overlap among AER categories. Given that normoalbuminuric patients may have advanced glomerulopathy, the selection of slow-track patients based on glomerular structure may better identify protected patients than AER alone.

Kidney biopsy is an indispensible procedure for making a pathologic diagnosis of renal diseases by fixing and staining the biopsy specimen. However, it is not a routine procedure to culture the cells from a renal biopsy specimen directly, or to utilize the cultured cells for any kind of diagnostic or functional evaluation. In this study, primary culture of the renal tubular epithelial cells was tried from a piece of percutaneous kidney biopsy specimen. Successive passages of the cells were possible until fourth passage. With these cells, morphologic characteristics of the cultured cells and integrin expression profiles were investigated. On light and electron microscopy, these cells were characterized by the cobblestone-like growth, presence of microvilli and tight junction, and the preservation of polarity. Immunohistochemical studies demonstrated the epithelial nature of these cells and particularly their differentiation from renal tubular epithelial cells, of either proximal or distal nephronic segment. The integrin profile confirms the epithelial nature of the cell. We hope that our results facilitate the understanding of pathophysiology of renal tubular cells from the patient directly.

Mucoid otitis media (MOM) is characterized by viscous fluid, high in mucin concentration, which accumulates in the middle ear cavity. Recent studies suggest that initial infection in the middle ear cleft may be key to the development of MOM. However, factors of the initial infection attributed to the stimulation of mucin production are not clearly understood. This study demonstrated that tumor necrosis factor (TNF)-alpha, a proinflammatory cytokine in mucoid effusion, markedly increased Muc2 mucin mRNA expression in middle ear epithelium, in a time- and dose-dependent manner. Parallel to this was a marked increase in mucin glycoprotein in middle ear fluid. Also, TNF-alpha demonstrated an autocrine and/or paracrine effect on the expression of endogenous TNF-alpha gene in the middle ear, which may contribute to the production of mucin in this study. These findings suggest that TNF-alpha plays an important role in the development of MOM by stimulating mucin metabolism.

Objective—To evaluate expression of the α6 chain of type IV collagen in the glomerular basement membranes (GBM) of healthy dogs. Sample Population—Kidney specimens from 12 healthy dogs. For comparison, kidney specimens from 8 human subjects between 25 and 83 years old also were evaluated. Procedure—Sections were immunolabeled with a monospecific antibody that cross-reacts with human and canine α6(IV) chains and examined by means of fluorescence microscopy. Results—Immunolabeling of the α6(IV) chain was not observed in GBM of 6 dogs ≤ 30 months old but was observed in GBM of the remaining 6 dogs, all of which were ≥ 45 months old. Expression of the α6(IV) chain was not observed in GBM of the human subjects, regardless of the age of the subject. Conclusions and Clinical Relevance—Results indicate that the α6(IV) chain is expressed in GBM of healthy dogs, but the expression is age-dependent. Composition and structural organization of type IV collagen in the GBM of healthy adult dogs is different from that described for other species. (Am J Vet Res 2000;61:38–41)

Mucins are heavily glycosylated proteins characterized by high molecular weight and heterogeneous structure. Mucin genes are expressed in a tissue- or epithelium-specific manner. Although mucins are known to be important structural components of the mucociliary transport system that protects epithelium against invading microorganisms, very little is known about mucin gene expression unique to the middle ear. This study demonstrated that middle ear messenger RNA specifically hybridized with rat MUC2 and human MUC2 (SMUC-41) complementary DNA probes. MUC3 and MUC5AC mucin genes, dominantly expressed in rodent intestine and trachea, were not detected in the rat middle ears in this study. The middle ear MUC2 messenger RNA harvested by lavage was characterized by a single transcript — unlike its counterpart in intestine and airways, which is characterized by polydispersity — suggestive of a better method for RNA analysis. It was concluded that rat middle ears possess a MUC2 mucin gene or homologue of human MUC2 (SMUC-41).

Pneumococcal otitis media is associated with the production of potent inflammatory mediators (leukotrienes), but the mechanism by which pneumococcus induces production of leukotrienes in the middle ear is poorly understood. In this study, up-regulation of 2 genes that govern the lipoxygenase pathway, cPLA2 and 5-LOX, was observed in rats following inoculation of pneumococcus into the middle ear cavity. Expression of cPLA2 was low, and 5-LOX gene expression was not detected in control animals. Up-regulation of cPLA2 and 5-LOX in middle ear epithelial cells was accompanied by an increase of high-molecular-weight glycoproteins in middle ear fluid and cells. These findings suggest that pneumococcus activates the lipoxygenase pathway by up-regulating expression of the cPLA2 and 5-LOX genes. This, in turn, may stimulate synthesis and secretion of high-molecular-weight glycoproteins that facilitate production of fluid in the middle ear cleft.

Entactin is an extracellular matrix glycoprotein which binds to laminin and is found in most renal basement membranes and in the glomerular mesangial matrix. In the present study, we have characterized specific integrin receptors on cultured human mesangial cells (CHMC) responsible for adhesion to native entactin. The integrin receptors alpha 2 beta 1, alpha 3 beta 1, alpha 5 beta 1, alpha v beta 3, alpha v beta 5, and alpha 6 complexed with either beta 1 or beta 4 could be immune precipitated from detergent extracts of metabolically labeled CHMC. Adhesion assays with inhibitory anti integrin monoclonal antibodies (mab) demonstrated that CHMC use both alpha v beta 3 and a beta 1-containing integrin to bind surfaces coated with native entactin. Optimal binding of CHMC to native entactin required the participation of cations. Using wild type and mutant recombinant entactin fragments, the binding site for the alpha v beta 3 receptor was localized to the RGD sequence on the rod or E domain of entactin. CHMC adhesion to mutant full length recombinant entactin ligands lacking the E domain RGD sequence confirmed the presence of ligand binding site(s) for beta 1 integrin receptor(s). Differences in CHMC binding characteristics to recombinant and full length entactin compared to native bovine basement membrane entactin were observed. This suggests that tertiary molecular structure may contribute to entactin ligand binding properties. Primary amino acid residue sequences and tertiary structure of entactin may play roles in forming functional cell attachment sites in native basement membrane entactin.

Redox regulation of renal DNA synthesis, transforming growth factor-β1 and collagen gene expression. Growth and injury represent recurrent and related themes in the study of progressive renal disease. We have previously demonstrated that a prooxidant diet, one deficient in antioxidants, selenium and vitamin E, induces renal enlargement, proteinuria, mild tubulointerstitial disease and diminished glomerular filtration rate (GFR). Our present study represents continued examination of these processes. We demonstrate that these diets increase thymidine incorporation into DNA and net DNA content in renal tissue, and induce expression of the mRNA for the proto-oncogene, c-myc, and the histone, H2b. We localize increased DNA synthesis as occurring mainly in the distal renal tubular epithelium. These deficient kidneys also exhibit interstitial expansion that parallels the pattern of DNA synthesis in that both processes are more prominent in the medulla than in the cortex. mRNAs for collagens I, III and IV in conjunction with transforming growth factor-β1 (TGF-β1) are up-regulated in the kidney in rats maintained on the deficient diet. In complementary in vitro studies, the exposure of rat kidney fibroblasts, NRK 49F cells, to noncytolytic doses of hydrogen peroxide, induces collagen III, collagen IV and TGF-β1 mRNA. Induction of these genes is also observed in mesangial cells so exposed to noncytolytic doses of hydrogen peroxide. A final aspect of our study was the examination of renal generation of hydrogen peroxide and the profile of the hydrogen peroxide-degrading enzymes. Deficient kidneys exhibit increased mitochondrial generation of hydrogen peroxide independent of oxygen consumption but in conjunction with suppression of glutathione peroxidase mRNA and activity. Lipid peroxidation was increased twofold in the cortex and medulla of the deficient kidneys. Surprisingly, catalase activity, measured in the cortex and medulla, and whole kidney catalase mRNA were also reduced in rats maintained on the antioxidant deficient diet, effects that may further compromise the clearance of hydrogen peroxide. These changes in catalase represent an adverse response to this dietary deficiency, and may be relevant to decreased catalase activity described in chronic renal insufficiency. Thus, a chronic prooxidant state, with features that mimic those of clinical uremia, increases DNA synthesis of renal tubular epithelium, induces mRNA expression for collagens I, III and IV in conjunction with the mRNA for the fibrogenic cytokine, TGF-β1. Oxidants also induce collagen III, collagen IV and TGF-β1 mRNA in vitro.

Complications that arise after thyroid surgery may be associated with infection, hemorrhage, hormonal problems, and laryngeal nerve injury. Voice alteration after thyroidectomy is usually caused by recurrent or superior laryngeal nerve injury. This voice dysfunction may also be associated with laryngotracheal fixation with impairment of vertical movement or by temporary malfunction of the strap muscles after surgery. In this study, we evaluated the voice function phonetically before and after thyroidectomy in 54 patients, although function of the recurrent and superior laryngeal nerves was normal. During surgery, the superior and recurrent laryngeal nerves were identified and protected, and after surgery electromyographic testing of the cricothyroid muscle was performed. Typical voice symptoms after surgery were easy fatigue during phonation and difficulty with high pitch and singing voice. Acoustic analysis revealed that the phonation time and fundamental frequency were not changed after surgery, but the speaking fundamental frequency, range of speaking fundamental frequency, and vocal range were significantly diminished after surgery. These data allowed us to suggest that the cause of voice dysfunction is not seen in neural lesions, but in a disturbance of the extralaryngeal skeleton. These voice changes emphasize the importance of the extralaryngeal mechanism for pitch control.

This paper proposes a battery power management strategy using Critical Surface Charge (CSC) information estimated by Extended Kalman Filter (EKF) in real time. The insight from CSC characterisation is used to propose a novel approach for supervisory control design of a series Hybrid Electric Vehicle (HEV). The underlying phenomenon determining the battery allowable power limits is closely connected to the CSC. The estimated CSC is processed with a Finite Impulse Response (FIR) filter to smoothen short-term fluctuations and highlight longer-term trajectories. The battery allowable power limits are adjusted based on the filtered CSC information to prevent undesirable battery operations.

To evaluate the therapeutic effects of topical antibiotic delivered by polylactic acid (PLA) polymer on paranasal sinusitis, we induced maxillary sinusitis in 32 New Zealand white rabbits by obstructing the maxillary sinus ostium and inoculating the sinus cavity with Streptococcus pneumoniae. The rabbits were divided into three groups: a control group (group 1) treated only by reopening the ostium, a group (group 2) treated by both reopening the ostium and injecting ampicillin (40 mg/kg/day), and a group (group 3) in which ampicillin in the PLA carrier (0.326 mg) was placed within the sinus after ostial patency was reestablished. The number of colony forming units (CFU) was lowest in group 3, followed by groups 2 and I. Ampicillin concentration in the maxillary sinus secretion of group 3 was significantly higher than in group 2. The results suggest that treatment with PLA-ampicillin polymer may maintain high therapeutic concentrations of ampicillin in maxillary sinus secretion.

Increasing evidence suggests that lipids may be important modulators of progressive glomerular injury. We previously reported the long-term glomerular changes in rats with dietary-induced hypercholesterolemia. In this work, we evaluated the early glomerular changes induced by hypercholesterolemia that precede the development of glomerulosclerosis. In cholesterol-fed rats, an early macrophage influx was observed. This was associated with an increase in glomerular size, mesangial matrix expansion, lipid deposits, and foam cell formation. Immunohistochemical techniques showed that type IV collagen, fibronectin, and laminin were increased in cholesterol-fed rats. The mRNA expression for the alpha 1 chain of type IV collagen and an inhibitor of type IV collagenase were increased, suggesting that both increased synthesis and reduced degradation may be involved in cholesterol-induced mesangial matrix accumulation. The glomerular mRNA expression of transforming growth factor-beta 1 was also upregulated, suggesting that transforming growth factor-beta 1 could be an important mediator for mesangial matrix accumulation in hypercholesterolemic states. The early cholesterol-induced changes in the glomerulus are reminiscent in many respects to the process leading to glomerulosclerosis in the vessel wall.

Platelet-activating factor (PAF) is a naturally occurring phospholipid that acts as a pleiotropic mediator and mediates cell-cell reactions under physiological and pathological conditions. Recently, it has been shown that PAF is a strong secretagogue of mucous glycoprotein in the airways, suggesting its role in mucous glycoprotein secretion and the pathogenesis of otitis media with effusion. In the current study, we examined the effect of PAF on mucous glycoprotein secretion in cultured chinchilla middle ear epithelial cells. PAF at 1 microM significantly stimulated mucous glycoprotein secretion from cultured chinchilla middle ear epithelial cells. This action was concentration-dependent, with secretions reaching near maximum when the cells were incubated with PAF at 100 microM. In a time-dependent study, PAF demonstrated an initial rapid stimulation of mucous glycoprotein secretion, followed by a gradual increase thereafter. A six-fold increase was seen in the first 2 h compared with controls. Cycloheximide, a protein synthesis inhibitor, demonstrated an inhibitory effect on PAF-stimulated mucous glycoprotein secretion in this study. These findings suggest that PAF plays an important role in the pathogenesis of otitis media with effusion by stimulating mucous glycoprotein secretion in vitro.

Effects of matrix glycation on mesangial cell adhesion, spreading and proliferation. We examined the effects of in vitro nonenzymatic glycosylation (NEG) of the extracellular matrix (ECM) on various aspects of the adhesive interaction between the ECM and human kidney mesangial (HKM) cells, and also on the ability of HKM cells to spread and proliferate. Isolated type IV collagen (tIV) or intact complexes of glomerular basement membrane and mesangial matrix (GBM/MM) were used as substrates following control incubation or modest glycation. We observed that HKM cells adhered less effectively to glycated tIV at early time intervals and were delayed in attaining maximal levels of adhesion compared to cells interacting with control tIV. The nature of the adhesive interaction was also different since antibodies which blocked the function of β 1 -containing integrins more effectively inhibited adhesion between HKM cells and glycated tIV than cells and control tIV. HKM cells interacting with glycated tIV also demonstrated less cell surface micro-spike and ruffle formation at five minutes after plating, less extensive spreading throughout the examined time intervals (≥ 90min after plating), and slightly increased cell numbers 5 to 10 days after plating when compared to cells interacting with control tIV. However, increased cell numbers were not observed when HKM cells were grown on glycated GBM/MM. Similar changes in response to glycated substrate were observed when HKM cells were grown in either 5 or 25mM glucose. In conclusion, relatively modest glycation of the ECM alone was sufficient to result in specific changes in HKM cell behavior in vitro . It is possible that the matrix glycation which occurs in the kidneys of diabetic patients could alter mesangial cell behavior in situ in ways which may contribute to the development of diabetic nephropathy.

Propylthiouracil, which is commonly used in the treatment of hyperthyroidism, has been associated in adults with antineutrophil cytoplasmic autoantibody, a serologic marker of vasculitis. Severe renal disease has not been reported as a complication of therapy with this drug. We report severe antineutrophil cytoplasmic autoantibody-positive vasculitis in children receiving propylthiouracil, as well as rapidly progressive crescentic glomerulonephritis after administration of this drug.

Recurrence of steroid-resistant nephrotic syndrome in kidney transplants is associated with increased acute renal failure and acute rejection. We performed 73 kidney transplants in 51 patients with steroid-resistant nephrotic syndrome (SRNS) with focal segmental glomerular sclerosis (FSG) ages 18.4 ± 12.8 (X ± sd) years. Recurrence of SRNS, defined by rapid onset of proteinuria, hypoalbuminemia and/or >95% epithelial cell foot process effacement with or without the presence of FSG, occurred in 26 grafts in 16 patients. Acute renal failure (ARF) occurred in 16 of 26 (61.5%) grafts with recurrence versus 7 of 47 (14.9%) grafts without recurrence (P < 0.0001). ARF occurred in 4 of 9 (44.4%) living-related donor (LRD) recipients with recurrence and 3 of 21 (12.5%) LRD recipients without recurrence (NS). ARF in cadaver donor (CAD) recipients with recurrence was 12 of 17 (70.5%) versus 4 of 23 (17.4%) without recurrence (P < 0.0001). ARF was also higher in LRD or CAD with recurrence than in a control group of non-SRNS patients matched for age, sex and time of transplantation. Graft survival at one year was lower in patients with recurrence and ARF [4 of 16 (25%)] compared to patients with recurrence and no ARF [9 of 11 (82%), P < 0.01]. There was no difference in graft survival in patients without recurrence who did or did not have ARF. One or more acute rejection episodes occurred in all 16 patients with ARF and recurrence, in all 7 patients with ARF without recurrence, and in 7 of 10 patients with recurrence without ARF compared with only 11 of 40 (28%) of patients with neither recurrence nor ARF (P < 0.0001

Glomerular distribution of type IV collagen in diabetes by high resolution quantitative immunochemistry. We examined type IV collagen distribution and density in human diabetic kidneys by quantitative immunogold electron microscopy. We studied normal kidney transplant donors and “slow-track” and “fast-track” insulin dependent diabetic (IDDM) patients. The “slow-track” patients had IDDM for ≥ 20 years and mesangial volume fraction (VvMes/glom) of ≤ 0.32. The “fast-track” patients had IDDM for ≤ 20 years and VvMes/glom ≥ 0.37. Renal biopsies were embedded in Lowicryl, reacted with polyclonal anti-type IV collagen (in the distribution of the classical α1(IV) and α2(IV) collagen chains) and monoclonal anti-α4(IV) collagen chain antibody followed by gold conjugated secondary antibody. We found, by morphometric techniques, a decrease in the immunogold densities of anti-type IV collagen in the subendothelial zone of the GBM in the “fast-track” IDDM patients. There was a trend towards a decrease in mesangial matrix (MM) particle density in the “fast-track” (P = 0.07) but not in the “slow-track” patients. However, because of the marked increase in MM in the “fast-track” patients, the per glomerulus estimated quantity of these antigens in MM was increased. In contrast, the density of α4(IV) collagen chain was increased in the epithelial zone of the GBM in the “fast-track” IDDM patients. It is not known whether these changes in glomerular type IV collagen represent markers of advanced diabetic lesions or whether these changes might be detected earlier in diabetic patients destined for the later development of serious lesions.

Because hypercholesterolemia and mesangial cell proliferation may be important in the pathogenesis of glomerulosclerosis, the effects of low-density lipoprotein (LDL) on human mesangial cell proliferation were evaluated. Native LDL (20 to 200 micrograms/mL) caused a dose-dependent increase in (3H)thymidine incorporation and increased mesangial cell numbers over 96 h. The mitogenic effect of LDL was partially blocked by the inhibition of cytochrome P-450, but not by the inhibition of cyclooxygenase or lipoxygenase pathways. Higher LDL concentrations (1,000 to 2,000 micrograms/mL) inhibited (3H)thymidine incorporation and reduced cell numbers, possibly as a result of the oxidative modification of LDL, indicated by an increase in thiobarbituric reactive substances. This peroxidation of LDL involved superoxide, because superoxide dismutase and butylated hydroxytoluene prevented it, whereas hydroxyl radical scavengers were without effect. Native LDL subjected to chemical oxidation by copper sulfate also inhibited mesangial cell proliferation. These results suggest that low concentrations of LDL may stimulate human mesangial cell proliferation, which may, in turn, cause the production of reactive oxygen molecules. Moreover, the oxidative modification of LDL may mediate the toxic effects of high LDL concentrations on human mesangial cells.

Thin-layer chromatography was used to examine the metabolism of arachidonic acid and prostaglandins (PGs) in freshly isolated and cultured middle ear epithelial cells from the chinchilla. The freshly isolated cells converted arachidonic acid predominantly to PGE2, while those cells grown in culture for 10 days acquired the ability to convert arachidonic acid to 6-keto-PGF1 alpha, PGD2, and PGE2. Incubation of the isolated cells and primary cultures with acetylsalicylic acid and indomethacin inhibited the formation of these PGs. These findings suggest that studies on the factors regulating arachidonic acid metabolism in middle ear epithelium may help to explain the role of eicosanoids in middle ear secretions, particularly in relation to the pathophysiology of otitis media.