Distribution of heat shock protein 108 mRNA in the chicken central nervous system

The constitutive expression of heat shock protein 108 (HSP108) mRNA is mapped in a normal chicken central nervous system using in situ hybridization technique. HSP108 mRNAs were found to be mainly localized in the small neuroglial cells of various regions of the brain, although some neuronal cells also showed positive signals. This tendency is observed to be more marked in the cerebellum; HSP108 signals were not found in the Purkinje cells, but in Bergmann glial cells and oligodendrocytes. Although neuronal cells in the deep cerebellar nuclei and the molecular layer showed occasional HSP108 signals, the expression pattern of HSP108 mRNA is different from homologous HSP90 that is mostly expressed in neurons, but rather similar to that of TfBP immunoreactivity, a new member of the HSP108 family. The constitutive neuroglial localization of HSP108 could suggest that HSP108 may play an important role in the normal metabolism of neuroglial cells in the chicken brain.

An endogenous proteinacious inhibitor in porcine liver for S-adenosyl-L-methionine dependent methylation reactions: identification as oligosaccharide-linked acyl carrier protein

A proteinacious inhibitor of S-adenosyl-L-methionine (AdoMet)-dependent transmethylation reactions was purified to homogeneity from porcine liver by size exclusion chromatography and FPLC. The molecular weight of the inhibitor was 12,222 Da. A 7400 Da polypeptide fragment of the purified inhibitor was sequenced by matrix-associated laser desorption ionization; time-of-flight MS, and was found to be identical with the known sequence of spinach acyl carrier protein (ACP). Although the remainder of the molecule was not clearly defined, 1H and H-H correlation of spectroscopy (COSY) NMR analysis revealed the presence of an oligosaccharide with alpha-glycosidic linkage. The purified oligosaccharide-linked ACP inhibited several AdoMet-dependent transmethylation reactions such as protein methylase I and II. S-farnesylcysteine O-methyltransferase, DNA methyltransferase and phospholipid methyltransferase. Protein methylase II was inhibited with a Ki value of 2.4 x 10(-3) M in a mixed inhibition pattern, whereas a well-known competitive product inhibitor S-adenosyl-L-homocysteine (AdoHcy) had Ki value of 6.3 x 10(-6) M. Commercially available active ACP fragments (65-74) and ACP from Escherichia coli had less inhibitory activity toward S-farnesylcysteine O-methyltransferase than the purified inhibitor. The biological significance of this oligosaccharide-linked ACP which has two seemingly unrelated functions (inhibitor for transmethylation and fatty acid biosynthesis) remains to be elucidated.

The prevalence and associated risk factors of renal artery stenosis in patients undergoing cardiac catheterization

Renal artery stenosis may be a cause of hypertension and a potential contributor to progressive renal insufficiency. However, the prevalence of renal artery disease in a general population is poorly defined. The purposes of this study were to evaluate the prevalence of angiographically-determined renal artery narrowing in a patient population undergoing routine cardiac catheterization, and to identify the risk factors for renal artery stenosis. After left ventriculography, abdominal aortography was performed to screen for the presence of renal artery stenosis. A total of 427 patients (274 males, 153 females) were studied and the mean age was 59 years. Renal artery narrowing was identified in 10.5% of patients. Significant (> or = 50% diameter narrowing) renal artery stenosis was found in 24 patients (5.6%) and insignificant stenosis was found in 21 patients (4.9%). Significant unilateral stenosis was present in 4.2% of patients and bilateral stenosis was present in 1.4%. The stem of the renal artery was a more common site of stenosis in 62.2% of patients than in the ostium (37.8%), but the severity of stenosis was not significantly different according to the site of stenosis. By univariate and multivariate logistic regression analysis, the association of clinical variables with renal artery stenosis was assessed. Multivariable predictors included age, hypertension and peripheral vascular disease (p < 0.05). The variables such as sex, smoking history, hyperlipidemia, renal insufficiency, as well as the presence of obesity, severity of coronary heart disease and D.M., were not associated. In conclusion, the prevalence of angiographically-determined renal artery narrowing in a patient population undergoing cardiac catheterization is 10.5%. Old age, hypertension and evidence of peripheral vascular disease represent the predictors of renal artery stenosis.

Studies on the antithrombotic and antiplatelet activities of NQ304, a newly synthesized naphthoquinone derivative

The effect of p6304 (2-chloro-3-(4-hexylphenyl)-amino-1,4-naphthoquinone) as a novel antithrombotic agent was investigated. NQ304 was found to inhibit platelet aggregation in human platelets in vitro and in rat ex vivo, and murine pulmonary thrombosis in vivo. NQ304 potently inhibited adenosine diphosphate (ADP), collagen, epinephrine and calcium ionophore-induced human platelet aggregation in vitro dose-dependently. In the ex vivo study, oral administration of NQ304 significantly inhibited platelet aggregation in rats. However, NQ304 was found not to affect the coagulation system, since it did not change the prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT). The agent prevented death due to pulmonary thrombosis by the platelet aggregates in mice in vivo. In the mouse tail bleeding time test, NQ304 showed a significant prolongation of the tail bleeding time in conscious mice. These results suggest that a principal antithrombotic effect of NQ304 may be due to the antiplatelet aggregation activity but not to anticoagulation activity.

Metabolic acidosis and composite nutritional index (CNI) in CAPD patients

BACKGROUND

Metabolic acidosis (MA) has been recognized as an important stimulus for net protein catabolism. Continuous ambulatory peritoneal dialysis (CAPD) is regarded to have advantage in normalizing the acid-base homeostasis over hemodialysis due to continuous supply of buffer. However, many CAPD patients still remain acidotic and the clinical impact of this MA is uncertain. Recent studies revealed no specific correlation between a certain degree of MA and protein nutritional status while others showed that mild alkalosis is nutritionally beneficial to CAPD patients. A cross-sectional study evaluating acid-base and nutritional status was performed to examine the relationship between acid-base status and overall nutritional status assessed by composite nutritional index (CNI) and to get a basic information about the optimal pH/HCO3 in CAPD patients.

PATIENTS AND METHODS

Total 198 clinically stable patients maintained on CAPD more than 6 months were evaluated. Each of 10 nutritional parameters of CNI consisting of clinical (subjective global assessment), biochemical (total lymphocyte count, albumin, prealbumin, insulin-like growth factor-1, transferrin) and anthropometric parameters (body mass index, % lean body mass, triceps skinfold thickness, midarm muscle circumference) was graded from 0 to 3 point (0; normal, 1; mildly decreased, 2; moderately decreased, 3; severely decreased).

RESULTS

Mean CNI score was 8.2 +/- 5.2 with a range of 0 to 25. CNI was positively correlated with age, duration of peritoneal dialysis, incidence of peritonitis, C-reactive protein (CRP), HCO3 and dialytic protein loss whereas it was inversely correlated with hemoglobin and nPNA. In patients with MA (n = 25, mean arterial HCO3 19.5 +/- 1.9 mM/l), CNI score was significantly lower (6.3 +/- 3.5) compared to patients with normal acid-base status (n = 63, 9.5 +/- 5.9, p < 0.01) or metabolic alkalosis (n = 47, 10.1 +/- 4.6, p < 0.001). Multiple regression analysis revealed that the incidence of peritonitis, duration of dialysis, CRP and dialytic protein loss were the independent predictors of CNI.

CONCLUSIONS

CAPD patients with mild to moderate degree of MA appear to be associated with more favorable overall nutritional status expressed as CNI. Prospective studies evaluating changes in the nutritional parameters with the correction of acid-base abnormality are needed to understand the real impact of acid-base status on nutritional status and to know the optimal pH/HCO3 in CAPD patients.

Reconstruction of upper chest wall defects with a function-preserving pectoralis major muscle flap: case report

The pectoralis major muscle or myocutaneous flap has a nearly 100% success rate in reconstructing chest wall defects. Major adverse sequelae resulting from the use of the pectoralis major muscle or myocutaneous flap are rarely reported in the literature. However, the loss of pectoralis major muscle function caused by the detachment of the muscle from its insertion on the humeral bone is of more and more concern. This is a significant loss for manual laborers when the patient tries to handle tools or control heavy machinery. A case of upper sternal osteomyelitis is reported. After wide debridement with partial excision of the sternum, the second and third ribs, the right pleura, and the lung were exposed. A right unilateral pectoralis major muscle flap was transposed to restore the defect. In addition, to preserve the lateral portion of the muscle and its insertion on the humerus, the origin of the lower sternocostal part of the pectoralis major muscle was transposed to the medial clavicle and residual upper sternum. In this way, not only was the chest wall defect reconstructed but the function of the residual pectoralis major muscle was also preserved. Postoperative follow-up at one year demonstrated no arm weakness, no limitation in shoulder range of motion, and no evidence of atrophy of the transposed pectoralis major muscle. Our experience with this function-preserving pectoralis major muscle flap was encouraging and we suggest it be employed in the reconstruction of the upper anterior chest wall.

Wegener's granulomatosis in the elderly

Wegener's granulomatosis classically involves the upper respiratory tract, lungs and kidneys. Rarely, it also affects the skin and heart. Cardiac involvement is uncommon in Wegener's granulomatosis and myocardial infarction is seldom highlighted. It can be a difficult diagnosis to make in the elderly who often have multiple co-existing illnesses. We present a case of a 75-year-old Chinese woman with interesting cardiac and dermatological manifestations of Wegener's granulomatosis.

Autotaxin (ATX), a potent tumor motogen, augments invasive and metastatic potential of ras-transformed cells

Autotaxin (ATX), an exo-nucleotide pyrophosphatase and phosphodiesterase, was originally isolated as a potent stimulator of tumor cell motility. In order to study whether ATX expression affects motility-dependent processes such as invasion and metastasis, we stably transfected full-length ATX cDNA into two non-expressing cell lines, parental and ras-transformed NIH3T3 (clone7) cells. The effect of ATX secretion on in vitro cell motility was variable. The ras-transformed, ATX-secreting subclones had enhanced motility to ATX as chemoattractant, but there was little difference in the motility responses of NIH3T3 cells transfected with atx, an inactive mutant gene, or empty vector. In MatrigelTM invasion assays, all subclones, which secreted enzymatically active ATX, demonstrated greater spontaneous and ATX-stimulated invasion than appropriate controls. This difference in invasiveness was not caused by differences in gelatinase production, which was constant within each group of transfectants. In vivo studies with athymic nude mice demonstrated that injection of atx-transfected NIH3T3 cells resulted in a weak tumorigenic capacity with few experimental metastases. Combination of ATX expression with ras transformation produced cells with greatly amplified tumorigenesis and metastatic potential compared to ras-transformed controls. Thus, ATX appears to augment cellular characteristics necessary for tumor aggressiveness.

Localization of bcl-2 mRNA in the rabbit central nervous system

In this study, we demonstrated bcl-2 expression in the rabbit brain using in situ hybridization and compared the results with the studies done on the other animals. Although the bcl-2 expressions of the rabbit were generally similar to those of the other animals, some differences were also found; the cells in molecular and Purkinje cell layers of the cerebellum, which were bcl-2 negative in the others, showed intense bcl-2 positive signals, while the ependymal cells, arachnoid villi and granular layer, which were positive in the other animals, were not well stained with bcl-2 riboprobes in the rabbit brain. Our findings clearly showed the similarities and differences of rabbit bcl-2 mRNA as compared with the other species for the first time, and provided the basis of further study on the properties of bcl-2 in this species.

Purification and characterization of epidermis-origin hemolymph protein in Galleria mellonella

Epidermis-origin hemolymph protein (EOHP) was identified and purified from the last instar larval hemolymph of Galleria mellonella by anion exchange chromatography, chromatofocusing chromatography, and Sephadex G-100. The EOHP has a native molecular mass of 47 kDa and is composed of one subunit. The isoelectric point of the EOHP was determined to be 5.3. The amino acid composition of the EOHP was rich in aspartic acid, glutamic acid and lysine, but poor in tyrosine, methionine, and tryptophan. EOHP is present in hemolymph over the period from the 4th instar larvae to the adult stage examined. Concentration of EOHP is high during the larval stage but gradually decreased during the developmental stage from pupal to adult stage. EOHP is present in the cuticle, fat bodies and trachea but not in hemocytes, fore gut, mid gut and hind gut.

Distribution of P2X receptor subtypes in the rat female reproductive tract at late pro-oestrus/early oestrus

Using immunohistochemistry techniques, we have examined the female reproductive organs of the rat in late pro-oestrus/early oestrus for the presence of purine nucleotide P2X1-7 receptors. In contrast to the male genital organs and the urinary tract, P2X1 receptors were present weakly, if at all, on smooth muscle membranes, except in blood vessels, whereas P2X2 immunoreactivity in smooth muscle was present in ovary and uterus as well as in blood vessels. Neither P2X1 nor P2X2 receptors were present in fallopian tubes. P2X5 receptors were seen in the differentiating cell layers of the stratified squamous vaginal epithelium and also in the very early stages of ovarian follicular development; P2X6 receptors were present in secondary follicles. P2X7 receptors, markers for programmed cell death, were present in the keratinised vaginal epithelium and also in the exfoliating superficial endometrial cells. The possible biological significance of these signalling molecules in the female reproductive tract is discussed.

Transcriptional repression of the transforming growth factor-beta type I receptor gene by DNA methylation results in the development of TGF-beta resistance in human gastric cancer

The transforming growth factor-beta (TGF-beta) signaling pathway subserves an essential tumor suppressor function in various cell types. A heteromeric complex composed of TGF-beta type I (RI) and type II (RII) receptors is required for TGF-beta signaling. We have identified a subset of human gastric cancer cell lines which are insensitive to TGF-beta and which express a low level of TGF-beta type I receptor mRNA relative to a gastric cancer cell line which is highly responsive to TGF-beta. Using these cells, we show that hypermethylation of a CpG island in the 5' region of the TGF-beta RI gene provides another potentially important mechanism of escape from negative growth control by TGF-beta. This hypermethylation was found in four of five human gastric cancer cell lines and five out of 40 (12.5%) primary tumors examined. In human gastric cancer cell lines, treatment with the demethylating agent, 5-aza-2'-deoxycytidine, resulted in increased expression of the TGF-beta RI gene, but not the RII gene. Transient transfection of an RI expression vector into the TGF-beta resistant SNU-601 cell line restores TGF-beta responsiveness. These findings suggest that one of the mechanisms of escape from autocrine or paracrine growth control by TGF-beta during carcinogenesis could involve aberrant methylation of CpG islands in the 5' region of the TGF-beta RI gene.

Differential expression of nitric oxide synthase in human stomach cancer

The level of expression and cellular localization of isoenzymes of nitric oxide synthase (NOS) was detected in human stomach tumor tissues. Tumor tissues showed 70% higher activity of NOS than that of normal tissues (P < 0.01). Poorly differentiated adenocarcinoma tend to have higher activity (P < 0.05) than well differentiated and moderately differentiated tumor tissues. Aminoguanidine (AG), 2-amino-5,6-dihydro-6-methyl-4H-1,3-thiazine (AMT), NG-monomethyl-L-arginine (L-NMMA), and Nomega-nitro-L-arginine (L-NNA) inhibited NOS activity in tumor tissues by 18, 14, 11 and 13%, respectively. The TNF-alpha mRNA expression was correlated with the inducible NOS (iNOS) level, which was high in adenocarcinomas and low in normal tissues. Tumor tissues showed higher expression of iNOS in gland epithelial cells but the level of eNOS was significantly decreased with an exception of concentrated localization in the proliferating capillary endothelium. These results revealed that isoforms of NOS might contribute differentially to growth and progression of human stomach tumor.

Hydrogen peroxide activates p70(S6k) signaling pathway

We investigated a possible role of reactive oxygen species (ROS) in p70(S6k) activation, which plays an important role in the progression of cells from G(0)/G(1) to S phase of the cell cycle by translational up-regulation of a family of mRNA transcripts that encode for components of the protein synthetic machinery. Treatment of mouse epidermal cell JB6 with H(2)O(2) generated extracellularly by glucose/glucose oxidase led to the activation of p70(S6k) and p90(Rsk) and to phosphorylation of p42(MAPK)/p44(MAPK). The activation of p70(S6k) and p90(Rsk) was dose-dependent and transient, maximal activities being in extracts treated for 15 and 30 min, respectively. Further characterization of ROS-induced activation of p70(S6k) using specific inhibitors for p70(S6k) signaling pathway, rapamycin, and wortmannin revealed that ROS acted upstream of the rapamycin-sensitive component FRAP/RAFT and wortmannin-sensitive component phosphatidylinositol 3-kinase, because both inhibitors caused the inhibition of ROS-induced p70(S6k) activity. In addition, Ca(2+) chelation also inhibited ROS-induced activation of p70(S6k), indicating that Ca(2+) is a mediator of p70(S6k) activation by ROS. However, down-regulation of 12-O-tetradecanoylphorbol-13-acetate (TPA)-responsive protein kinase C (PKC) by chronic pretreatment with TPA or a specific PKC inhibitor Ro-31-8220 did not block the activation of p70(S6k) by ROS, indicating that the activation of TPA-responsive PKC was not required for stimulation of p70(S6k) activity by H(2)O(2) in JB6 cells. Exposure of JB6 cells to platelet-derived growth factor or epidermal growth factor led to a rapid increase in H(2)O(2), phosphorylation, and activation of p70(S6k), which were antagonized by the pretreatment of catalase. Taken together, the results suggest that ROS act as a messenger in growth factor-induced p70(S6k) signaling pathway.

Inhibitory activity of nm23-H1 on invasion and colonization of human prostate carcinoma cells is not mediated by its NDP kinase activity

The human nm23-H1 gene product, a putative metastasis suppressor, was identified as nucleoside diphosphate kinase (NDPK) A isoform. To investigate the functional effect of nm23-H1's NDPK activity on its suppression of the components of metastatic phenotype, we transfected a human prostate carcinoma cell line, DU145, with the cDNA encoding nm23-H1 mutant protein lacking NDPK activity. The mutant nm23-H1 transfected cell lines displayed decreased invasiveness and colonization in soft agar as the wild-type nm23-H1 transfectants did when compared with the control transfected line. The results suggest that the metastasis suppressing function of nm23-H1 is independent of the NDPK enzymatic activity.

The anti-inflammatory and hepatoprotective effects of fractions from Cudrania cochinchinensis var. gerontogea

Various fractions of the ethanol extract from the root wood of Cudrania cochinchinensis var. gerontogea (Moraceae) were evaluated for their anti-inflammatory effects on carrageenan-induced edema and hepatoprotective activities on carbon tetrachloride (CCl4)-induced and D-galactosamine-(D-GalN) induced acute hepatotoxicity in rats. The fractions (n-hexane, CHCl3, EtOAc, n-BuOH, and H2O) displayed significant inhibitory activity against carrageenan-induced edema, and the active anti-inflammatory components were further localized in the n-BuOH fraction, which exhibited the greatest anti-inflammatory effect, an effect 5% greater than indomethacin (which was used as a standard reference substance). Each fraction exerted a significant hepatoprotective effect by reducing enzymatic alteration (sGOT and sGPT) and by improving hepatic lesions, including liver centrilobular inflammation, cell necrosis, fatty change, ballooning degeneration in CCl4-induced acute hepatitis; and necrosis of the portal area in D-GalN-induced acute liver injury. The n-BuOH and EtOAc fractions had the greatest hepatoprotective effects on CCl4-induced liver injury; in contrast, the CHCl3 fraction was most potent against D-GalN intoxication, which is comparable to silymarin, as a recognized hepatoprotective drug.

Heart failure in Korean elderly patients — clinical features, prognosis and prognostic factors

Heart failure (HF) is very common in the elderly but there are not sufficient data about the clinical characteristics and prognostic factors of HF among the Asian elderly patients. The aim of the study was to find out the clinical characteristics, survival, and prognostic factors of HF in Korean elderly patients. Among elderly patients admitted from February 1995 to February 1998, the patients with a discharge diagnosis of HF were enrolled. Through the medical record review, the diagnosis was confirmed and clinical parameters to affect survival were identified. Total number of the subjects was 104 [age: 77+/-7 years (65-96), male:female=36:68, follow-up duration: 20+/-14 months, LVEF: 46+/-16%]. Ischemic heart disease (IHD) was the most common cause of HF (42%) followed by valvular heart disease (28%), and hypertension (20%). The 1-year survival rate was 71.3%. Advanced age [risk ratio (RR): 1.41 per 5 years of age; 95% CI: 1.11-1.80] and reduced left ventricular ejection fraction (0.69 per 10%, 0.52-0.93), poor initial functional class (2.40, 1.15-5.00), diabetes (2.79, 1.30-5.97) and past history of HF (2.37, 1.10-5.10) badly affected the survival rates. When the Cox proportional hazard model was applied for multivariate analysis, only aging (1.64 per 5 years of age, 1.19-2.28) and diabetes (4.92, 1.83-13.23) predicted poor prognosis. Twenty-seven percent of the patients had diastolic HF (LVEF>45%, LVEDD<55 mm) who had higher survival rates with marginal significance (0.35, 0.10-1.17, P=0.09).

Association between apolipoprotein E polymorphism and macroalbuminuria in patients with non-insulin dependent diabetes mellitus

OBJECTIVES

Apolipoprotein E (apo E) is known to play an important role in lipoprotein metabolism through its ability to bind to the receptors as a ligand. Three different apo E alleles (epsilon2, epsilon3 and epsilon4) produce six apo E genotypes (epsilon2/2, epsilon2/3, epsilon2/4, epsilon3/3, epsilon3/4 and epsilon4/4). The objective of this study was to investigate an association between apo E gene polymorphism and macroalbuminuria in 167 Korean patients with non-insulin dependent diabetes mellitus (NIDDM).

METHODS

The patients in the macroalbuminuria group (n = 74) represent those in whom 24 h urinary albumin excretion was above 300 mg. The patients in the normoalbuminuria group (n = 93) represent those in whom 24 h urinary albumin excretion was below 30 mg and serum creatinine levels were less than 1.2 mg/dl. The duration of diabetes in all patients was at least 8 years.

RESULTS

There were no significant differences in terms of age, sex, body mass index, HbA1c, total cholesterol, triglyceride, HDL-cholesterol and LDL-cholesterol between the two groups. In the macroalbuminuria group, the distribution of apo E genotypes revealed epsilon2/2 2 (2.7%), epsilon2/3 14 (18.9%), epsilon2/4 0 (0%), epsilon3/3 47 (63.5%), epsilon3/4 11 (14.9%) and epsilon4/4 0 (0%). In the normoalbuminuria group, the distribution of apo E genotypes revealed epsilon2/2 0 (0%), epsilon2/3 7 (7.5%), epsilon2/4 1 (1.1%), epsilon3/3 72 (77.4%), epsilon3/4 12 (12.9%) and epsilon4/4 1 (1.1%). There was no significant difference in the distribution of apo E genotypes between the two groups. However, there was a significant difference in the allele frequencies, epsilon2 frequency was significantly higher in macroalbuminuria group compared to normoalbuminuria group (12.2% vs 4.3%, P<0.05). Also, we compared apo E carrier frequencies between the two groups. Epsilon2 carrier frequency was significantly higher in macroalbuminuria group compared to normoalbuminuria group (21.6% vs 7.6%, P<0.05). In each group, there was no significant difference in the degree of lipid abnormalities between apo epsilon2 carrier (epsilon2/2, epsilon2/3 genotypes), epsilon3 carrier (epsilon3/3 genotype) and epsilon4 carrier (epsilon3/4, epsilon4/4 genotype).

CONCLUSION

Apo epsilon2 allele and epsilon2 carrier frequencies were significantly higher in macroalbuminuria group. These results suggest that epsilon2 allele may be associated with the development of clinical albuminuria in Korean patients with NIDDM.

Current status of peritoneal dialysis in Korea: efforts to achieve optimal outcome

Since its introduction in 1981, peritoneal dialysis (PD) has become firmly established as an effective mode of renal replacement therapy and serves an increasing patient population in Korea. The latest registry data indicate that about 3700 end-stage renal disease patients are maintained on chronic PD, representing 24.1% of the country's dialysis population. The majority (93.3%) of these patients are on continuous ambulatory peritoneal dialysis (CAPD) using the two-bag disconnect system, while only 3.3% are on automated PD. Under current renal reimbursement policies, most dialysis patients have to pay 20% of dialysis fees. Thus CAPD patients on 4 x 2-L daily exchanges pay about US$200 per month, not including medication and travel costs. Traditionally, most PD centers in Korea have used the "standard" prescription of 4 exchanges of 2 L of solution for most of their patients. A recent survey of 1467 patients who commenced CAPD in 1997 revealed that 84% of these patients were initially prescribed 4 x 2-L exchanges, while 12% were given a daily volume of 6 L. With this standard prescription, the percentages of Korean CAPD patients initially achieving the adequacy target of Kt/V urea > or = 2.0 and standardized creatinine clearance (SCCr) > or = 60 L/week/1.73 m2, were 74.4% and 82.1%, respectively. It is likely that, among current Korean CAPD patients, a much lower percentage will achieve the clearance targets compared to this initial outcome, but the precise data are not available. However, it is not clear whether the levels of small-solute clearance recommended for optimal PD outcomes, and proposed by the NKF-DOQI guidelines, will bring the expected benefits to Korean patients. Overall survival of Korean PD patients appears to be as good as, or even better than, that in most other countries. Recently, a single large PD center reported patient survival of 92.1%, 85.6%, 81.4%, and 67.6% at 1, 2, 3, and 5 years respectively. Other centers also reported similar outcomes. As in other countries, cardiovascular deaths predominate among Korean patients: death was due to cardiac causes in 29%, to vascular causes in 21%, and to infectious causes in 24%. Peritonitis is the most important barrier to prolonged use of CAPD in Korea, and more PD patients transfer to hemodialysis because of peritonitis than in other countries. To further reduce the morbidity and mortality of Korean PD patients, various control measures need to be implemented that can reduce or prevent peritonitis and other infectious complications. Also, to further improve long-term patient outcome, Korean nephrologists need to establish and practice optimal clearance targets in the chronic care of these patients.

Posttranslational mechanisms contribute to the suppression of specific cyclin:CDK complexes by all-trans retinoic acid in human bronchial epithelial cells

Retinoids have demonstrated activity in the chemoprevention of aerodigestive tract cancer. Potentially contributing to their lung cancer chemopreventive effects, retinoids inhibit the growth of human bronchial epithelial (HBE) cells. We observed previously that all-trans retinoic acid (t-RA) arrests the growth of HBE cells in the G0 phase of the cell cycle through activation of retinoic acid receptor-dependent pathways, which enhances the association of E2F-4 with retinoblastoma protein family members, converting E2F into a transcriptional suppressor. In this study, we examined the mechanism by which t-RA blocks cell cycle progression in HBE cells and the possibility that this signaling event is blocked in non-small cell lung cancer (NSCLC) cells that are refractory to the growth inhibitory effects of t-RA. t-RA suppressed the expression and activity of cyclin D1, cyclin E, and cyclin-dependent kinases (CDK)-2 and CDK-4, increased expression of the CDK inhibitor p27, and shifted the retinoblastoma protein to a hypophosphorylated form. Posttranslational mechanisms contributed to the changes in CDK-2, CDK-4, and p27 levels, which, in the case of CDK-4, involved the ubiquitin-proteasome pathway. In contrast, despite retinoic acid receptor transcriptional activation, these signaling events did not occur in a NSCLC cell line that is refractory to growth inhibition by t-RA. These findings provide the first evidence that t-RA activates degradation of CDK-4 through the ubiquitin-proteasome pathway, a novel mechanism by which t-RA causes HBE cells to exit the cell cycle, and blockade of these signaling events may contribute to the development of retinoid resistance in NSCLC cells.

In situ localization of neuronal nitric oxide synthase (nNOS) mRNA in the rat retina

We performed a comparative study on the distribution of neuronal nitric oxide synthase (nNOS) immunoreactivity and mRNA in a normal rat retina using immunocytochemistry and in situ hybridization technique. As in previous studies, we found NOS immunoreactive (NOS-IR) cells and fibers in inner and outer plexiform layers (IPL and OPL), inner nuclear layer (INL) and inner photoreceptor segment (IPS). However, very little nNOS-IR could be detected in groups of amacrine cells and ganglion cells localized in ganglion cell layer (GCL). However, in situ hybridization showed that intense NOS mRNA signals were mainly found in the GCL and INL while weak or no mRNA signals were detected in IPL, OPL, outer nuclear layer (ONL) and IPS. This difference suggests that nNOS proteins may be transported through axons into the terminals in the IPL and OPL after they were synthesized with nNOS mRNA templates in the INL. In the case of nNOS mRNA in GCL, synthesizing nNOS proteins may move outside the eyeball and carry out tasks in central nervous system. The difference of nNOS mRNA and nNOS IR means that the complete concurrence of nNOS IR and in situ hybridization results may not always occur in the rat retina.

In situ localization of p53, bcl-2 and bax mRNAs in rat ocular tissue

We mapped p53, bcl-2 and bax mRNAs, which are known to have correlation with apoptotic cell death, in the rat ocular tissue. p53 mRNA signals were present in several layers of retina, optic nerve, corneal epithelium, ciliary process and posterior surface of the iris. While almost the same pattern as p53 was recognized in the case of bcl-2 mRNA, bax signals were not found in ocular tissue except for ganglion cell layer (GCL). These results suggest that in the normal ocular tissue, p53 and bcl-2 genes play opposing parts in the physiological control of cell survival and death. A p53 mediated tumor-suppressing action might occur through the induction of transcriptional targets other than bax because only in GCL were p53 and bax mRNA expression co-localized.

Relationship of peritoneal membrane transport characteristics to the nutritional status in CAPD patients

BACKGROUND

The study was carried out to evaluate the role of individual peritoneal membrane transport characteristics in the nutritional status expressed as the composite nutritional index (CNI) METHODS: Cross-sectional analyses of the overall nutritional status of 147 continuous ambulatory peritoneal dialysis (CAPD) patients were performed using the CNI. CNIs based on a scoring system of 10 nutritional indices including subjective global assessment, biochemical parameters and anthropometry were compared according to the results of a standard peritoneal equilibration test (PET) RESULTS: Patients were classified as low (n = 16, 10.9%), low average (n=59, 40.2%), high average (n=54, 36.7%) and high (n=18, 12.2%) transporters based on the D/P(Cr) after 4 h dwells. The mean 4 h D/P(Cr) was 0.65 +/- 0.12 (0.34-0.95), and there was no significant correlation between D/P(Cr) and other demographic parameters such as age, duration of peritoneal dialysis and body surface area. D/P(Cr) was correlated with dialytic albumin loss (r=0.47, P<0.001), serum albumin (r=-0.46, P<0.001), serum creatinine (r= -0.38, P<0.001), serum TGF-1 (r=-0.37, P<0.01) and LBM(Cr) (r= -0.26, P<0.05). In high transporters, the serum albumin was significantly lower while dialysate protein and albumin losses were significantly greater compared with low transporters. Serum creatinine and IGF-1 concentrations as well as LBM(Cr) were also decreased in higher transporters. The mean CNI score was 8.1 +/- 4.9, with a range of 0-24. CNI was positively correlated with age, duration of peritoneal dialysis, incidence of peritonitis, CRP and dialytic protein loss, whereas it was inversely correlated with ultrafiltration volume, haemoglobin and NPNA. The CNI score was significantly higher in high transporters compared with low transporters (11.7 +/- 4.3 vs. 5.9 +/- 1.6, P < 0.01). There was also a significant correlation between D/P(Cr) and CNI (r = 0.29, P < 0.05). Multiple regression analysis revealed that the incidence of peritonitis, duration of CAPD, CRP and D/P(Cr) were the independent factors affecting the CNI.

CONCLUSION

Peritoneal membrane transport characteristics correlate with the overall nutritional status of peritoneal dialysis patients assessed by the scoring system of the CNI, although it is associated with a different impact on the individual nutritional indices. The results of this cross-sectional study also suggest that a high permeability state is a risk factor for malnutrition in CAPD patients. Prospective studies evaluating the changes in nutritional parameters among patients with different membrane transport rates are needed to understand better the relationship of peritoneal membrane characteristics to the nutritional status of CAPD patients.