Epac2a-null mice exhibit obesity-prone nature more susceptible to leptin resistance.

BACKGROUND: The exchange protein directly activated by cAMP (Epac), which is primarily involved in cAMP signaling, has been known to be essential for controlling body energy metabolism. Epac has two isoforms: Epac1 and Epac2. The function of Epac1 on obesity was unveiled using Epac1 knockout (KO) mice. However, the role of Epac2 in obesity remains unclear. METHODS: To evaluate the role of Epac2 in obesity, we used Epac2a KO mice, which is dominantly expressed in neurons and endocrine tissues. Physiological factors related to obesity were analyzed: body weight, fat mass, food intake, plasma leptin and adiponectin levels, energy expenditure, glucose tolerance, and insulin and leptin resistance. To determine the mechanism of Epac2a, mice received exogenous leptin and then hypothalamic leptin signaling was analyzed. RESULTS: Epac2a KO mice appeared to have normal glucose tolerance and insulin sensitivity until 12 weeks of age, but an early onset increase of plasma leptin levels and decrease of plasma adiponectin levels compared with wild-type mice. Acute leptin injection revealed impaired hypothalamic leptin signaling in KO mice. Consistently, KO mice fed a high-fat diet (HFD) were significantly obese, presenting greater food intake and lower energy expenditure. HFD-fed KO mice were also characterized by greater impairment of hypothalamic leptin signaling and by weaker leptin-induced decrease in food consumption compared with HFD-fed wild-type mice. In wild-type mice, acute exogenous leptin injection or chronic HFD feeding tended to induce hypothalamic Epac2a expression. CONCLUSIONS: Considering that HFD is an inducer of hypothalamic leptin resistance and that Epac2a functions in pancreatic beta cells during demands of greater work load, hypothalamic Epac2a may have a role in facilitating leptin signaling, at least in response to higher metabolic demands. Thus, our data indicate that Epac2a is critical for preventing obesity and thus Epac2a activators may be used to manage obesity and obesity-mediated metabolic disorders.

Self-expandable metal stents for malignant esophageal obstruction: a comparative study between extrinsic and intrinsic compression.

Self-expandable metal stents (SEMSs) are effective for malignant esophageal obstruction, but usefulness of SEMSs in extrinsic lesions is yet to be elucidated. This study is aimed at evaluating the clinical usefulness of SEMSs in the extrinsic compression compared with intrinsic. A retrospective review was conducted for 105 patients (intrinsic, 85; extrinsic, 20) with malignant esophageal obstruction who underwent endoscopic SEMSs placement. Technical and clinical success rates were evaluated and clinical outcomes were compared between extrinsic and intrinsic group. Extrinsic group was mostly pulmonary origin. Overall technical and clinical success rate was 100% and 91%, respectively, without immediate complications. Extrinsic and intrinsic group did not differ significantly in clinical success rate. The median stent patency time was 131.3 ± 85.8 days in intrinsic group while that of extrinsic was 54.6 ± 45.1 due to shorter survival after stent insertion. The 4-, 8-, and 12-week patency rates were 90.5%, 78.8%, and 64.9% respectively in intrinsic group, while stents of extrinsic group remained patent until death. Uncovered, fully covered, and double-layered stent were used evenly and the types did not influence patency in both groups. In conclusion, esophageal SEMSs can safely and effectively be used for malignant extrinsic compression as well as intrinsic.

Esophageal mucosal mast cell infiltration and changes in segmental smooth muscle contraction in noncardiac chest pain.

Mast cells release potent mediators that alter enteric nerve and smooth muscle functions and may contribute to the pathogenesis of functional gastrointestinal disorders. The goal of this study was to determine if mucosal mast cell infiltration was associated with smooth muscle segmental changes in esophageal contraction. All patients with noncardiac chest pain (NCCP) were divided into two groups consisting of patients with non-erosive reflux disease or functional chest pain (FCP) according to the results of ambulatory 24 hours esophageal pH monitoring and high-resolution manometry. Pressure-volume (PV) was calculated by multiplying the length of the esophageal segment, duration of the contraction, and mean pressure over the entire space-time box (P mean). Quantification of mast cells was performed in five consecutive nonoverlapping immunostained sections. Spearman correlation analysis showed that the distal segment PV correlated with the mast cell count in all of the patients combined and in patients with FCP with correlation coefficients of 0.509 and 0.436, respectively (P = 0.004 and P = 0.042). Similar findings were observed for the segmental ratio of distal to proximal smooth muscle PV in all patients and in patients with FCP (correlation coefficients 0.566; P = 0.001 and correlation coefficients 0.525; P = 0.012, respectively). Mucosal mast cell infiltration was associated with distal esophageal contraction as a key pathophysiologic factor of NCCP.

Time-course microarrays reveal modulation of developmental, lipid metabolism and immune gene networks in intrascapular brown adipose tissue during the development of diet-induced obesity.

OBJECTIVE: The aim of this study was to establish the time-course of molecular events in intrascapular brown adipose tissue (iBAT) during the development of diet-induced obesity using microarrays and molecular network analysis. DESIGN: C57BL/6J male inbred mice were fed a high-fat diet (HFD) or normal diet (ND) and killed at multiple time-points over 24 weeks. METHODS: Global transcriptional changes in iBAT were determined by time-course microarrays of pooled RNA (n=6, pools per time-point) at 2, 4, 8, 20 and 24 weeks using Illumina MouseWG-6 v2.0 Beadchips. Molecular networks were constructed using the Ingenuity knowledgebase based on differentially expressed genes at each time-point. RESULTS: Body weight and subcutaneous adipose were progressively increased over 24 weeks, whereas iBAT was significantly increased between 6 and 12 weeks in HFD-fed C57BL/6J mice compared with controls. Blood glucose and insulin levels were increased between 16 and 24 weeks. Time-course microarrays, revealed 155 differentially expressed genes at one or more time-points over 24 weeks in the iBAT of HFD-fed mice compared with controls. Time-course network analysis revealed a network of skeletal muscle development genes that was activated between 2 and 4 weeks, subsequently a network of immune trafficking genes was activated at 8 weeks. After 20 and 24 weeks, multiple lipid metabolism and immune response networks were activated. Several target genes identified by time-course microarrays were independently validated using RT-qPCR. Tnnc1 was upregulated early between 2 and 4 weeks, later Cd68 and Col1a1 were upregulated between 20 and 24 weeks, whereas 11ß-hydroxysteroid dehydrogenase (Hsd11b1) was consistently downregulated during the development of diet-induced obesity. CONCLUSION: Molecular networks in iBAT are modulated in a time-dependent manner in response to a HFD. A broad range of gene targets exists to alter molecular changes within iBAT during the development of diet-induced obesity.

Efficacy of leukotriene receptor antagonist for erosive esophagitis: a preliminary retrospective comparative study.

While diagnostic overlap exists between gastroesophageal reflux disease and eosinophilic esophagitis especially on histological findings, therapeutic approaches for the two disease entities are very different. Recently, anti-inflammatory treatment, in addition to acid suppressants, has been investigated for gastroesophageal reflux disease. This study investigated whether the incidence of endoscopic erosive esophagitis was lower in recipients of long-term leukotriene receptor antagonist (LTRA) treatment. This retrospective comparative study included 207 recipients of an LTRA and an equal number of controls who underwent screening upper endoscopic examination. Twenty-two (10.6%) and 51 (24.6%) cases of erosive esophagitis were detected in the LTRA and control groups, respectively (P < 0.001). A significantly higher incidence of minimal change esophagitis was also found in the controls compared with the LTRA group (14.5% vs. 2.4%, P < 0.001). On multivariate analysis, LTRA treatment was significantly and inversely associated with erosive esophagitis (odds ratio [OR], 0.25; 95% confidence interval [CI], 0.13 to 0.46). Within the LTRA treatment group, an increased risk of erosive esophagitis was strongly associated with the presence of hiatal hernia (OR, 5.89; 95% CI, 2.20-15.73, P < 0.001) and short duration of LTRA treatment (OR, 0.64; 95% CI, 0.37-0.89, P= 0.022). In conclusion, this preliminary retrospective analysis demonstrated that patients who underwent long-term treatment with a LTRA had low incidence of endoscopic minimal change esophagitis.

Histologic diagnosis based on forceps biopsy is not adequate for determining endoscopic treatment of gastric adenomatous lesions.

BACKGROUND AND STUDY AIMS: Controversy persists around the treatment of gastric low-grade dysplasia (LGD). The aim of this study was to investigate possible indications for the endoscopic resection of gastric LGD through analysis of the histologic discrepancies between specimens of gastric LGD obtained by forceps biopsy and by endoscopic mucosal resection (EMR), and of their clinicopathologic characteristics. PATIENTS AND METHODS: The study involved 293 gastric LGD that were histologically proven on the basis of forceps biopsy in Severance Hospital between January 2004 and December 2007. Twenty cases were regularly followed up, and the remaining 273 were resected by EMR. We performed univariate and multivariate analyses of clinical and endoscopic characteristics including lesion size, number of biopsy fragments, and endoscopic appearance, in order to analyze the factors affecting histologic discrepancies. RESULTS: Of the 273 lesions resected by EMR, 207 (75.8 %) showed concordant histology, whereas for 51 (18.7 %) the histology was upgraded after endoscopic resection. Lesion size, absence of whitish discoloration, and the presence of spontaneous bleeding were found by univariate analysis to be statistically significant factors predicting an upgraded histology after EMR ( P = 0.026, P < 0.001, and P = 0.025, respectively). Multivariate analysis also showed absence of whitish discoloration to be a statistically significant factor influencing histologic discrepancies ( P = 0.001, odds ratio 5.29, 95 % confidence interval 1.95 - 14.37). Perforation and bleeding rates associated with EMR for LGD were 0.7 % and 6.2 %, respectively. Twenty patients who did not undergo EMR were followed up for a mean of 22 months, and 3 were revealed to have adenocarcinoma and 1 high-grade dysplasia on the latest histologic exam. CONCLUSIONS: We should consider endoscopic resection for gastric LGD that are 2 cm or more in size and do not have whitish discoloration.

Survey of PCDDs and PCDFs in air and soil around various incinerators in Korea, 2003-2007.

To investigate the levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) pollution in soils and air around incinerators, a total of 574 soil and 48 air samples were collected around 22 incineration facilities in Korea from 2003 to 2007. The concentrations of PCDD/Fs in the flue gases and air ranged from 0.01 to 21.50 ng I-TEQ Sm(-3) and 0.0002 to 9.95 pg I-TEQ Sm(-3), respectively whereas concentrations in soils ranged from n.d. to 153.23 pg I-TEQ g(-1) dw. The average value was 8.14 pg I-TEQ g(-1) dw in soil samples.

Caudal midazolam does not affect sevoflurane requirements and recovery in pediatric day-case hernioplasty.

BACKGROUND: This prospective, randomized, double-blind study aimed to determine whether caudal midazolam combined with ropivacaine affects anesthetic requirements, recovery profiles, and post-operative analgesia compared with ropivacaine alone in pediatric day-case hernioplasty. METHODS: Sixty boys (2-5 years old) received caudal injections of 0.2% ropivacaine 1 ml/kg and epinephrine 1 : 200,000 with (RM group) or without (R group) 50 microg/kg of midazolam under sevoflurane anesthesia. The sevoflurane requirement was determined by adjusting to a bispectral index score=50. RESULTS: Concentrations of end-tidal sevoflurane (ETsevo%) after induction were similar in both groups. After caudal block, ETsevo% before and after surgical stimuli did not show significant intra- or intergroup differences. Recovery characteristics, including post-operative sedations, were similar in both groups. Post-operative pain scores were significantly lower in the RM group than the R group. CONCLUSIONS: Caudal midazolam (50 microg/kg) added to 2% ropivacaine did not influence sevoflurane requirement or recovery but improved post-operative analgesia compared with ropivacaine alone in pediatric day-case hernioplasty.

The effect of pneumoperitoneum and Trendelenburg position on acute cerebral blood flow-carbon dioxide reactivity under sevoflurane anaesthesia.

This study compared cerebral blood flow-carbon dioxide (CBF-CO2) reactivities in the supine and modest Trendelenburg position under pnemoperitoneum during sevoflurane anaesthesia. After induction of anaesthesia in 25 patients, mechanical ventilation was adjusted to increase Paco2 from 4.7 (T1) to 6.0 kPa (T2) in the supine position, and the change in jugular bulb oxygen saturation was measured as an index of CBF. Then, after establishment of pneumoperitoneum and 30 degrees Trendelenburg position, the CO(2) step and measurement of CBF were repeated. The CBF-CO2 reactivity was 7.5 (3.3) %xkPa(-1) (% change in jugular bulb oxygen saturation per unit change in Paco2) in the supine position and 6.8 (2.3) %xkPa(-1) in the 30 degrees Trendelenburg-pneumoperitoneum condition (p = 0.086). We conclude that CBF-CO2 reactivity is unchanged by the modest Trendelenburg position under pneumoperitoneum during sevoflurane anaesthesia.

Attentional Engagement for Pain-Related Information among Individuals with Chronic Pain: The Role of Pain Catastrophizing.

Although the evidence of the attentional bias of chronic pain individuals toward pain-related information is established in the literature, few studies examined the time course of attention toward pain stimuli and the role of pain catastrophizing on attentional engagement toward pain-related information. This study examined the time course of attention to pain-related information and the role of pain catastrophizing on attentional engagement for pain-related information. Participants were fifty young adult participants with chronic pain (35% male, 65% female; M = 21.8 years) who completed self-report questionnaires assessing pain catastrophizing levels (Pain Catastrophizing Scale (PCS)), depression (the Center for Epidemiologic Studies Depression Scale (CES-D)), anxiety (State-Trait Anxiety Inventory (STAI)), and pain disability (the Pain Disability Index: (PDI)). Attentional engagements to pain- and anger-related information were measured by the eye tracker. Significant interaction effects were found between (1) time and stimulus type for pain-related information (F (5, 245) = 11.55, p < 0.001) and (2) bias scores and pain catastrophizing (F (1, 48) = 6.736, p < 0.05). These results indicated that the degree of increase for pain bias scores were significantly greater than anger bias scores as levels of pain catastrophizing increased. Results of the present study provided the evidence for the attentional bias and information processing model which has clinical implications; high levels of pain catastrophizing may impair individuals' ability to cope with chronic pain by increasing attentional engagement toward pain-related information. The present study can add knowledge to attentional bias and pain research as this study investigated the time course of attention and the role of pain catastrophizing on attentional engagement toward pain-related information for adults with chronic pain conditions.

Simultaneous monitoring technique for ASE and MPI noises in distributed Raman Amplified Systems.

We develop a new technique for simultaneously monitoring the amplified spontaneous emission (ASE) and multi-path interference (MPI) noises in distributed Raman amplified (DRA) systems. This technique utilizes the facts that the degree-of polarization (DOP) of the MPI noise is 1/9, while the ASE noise is unpolarized. The results show that the proposed technique can accurately monitor both of these noises regardless of the bit rates, modulation formats, and optical signal-to-noise ratio (OSNR) levels of the signals.

Differential effect of HTLV infection and HTLV Tax on interleukin 3 expression.

To characterize the interactions between human T-cell leukemia virus (HTLV) infection and cellular gene expression, we examined the expression of the lymphokine interleukin 3 (IL-3) in the presence and absence of HTLV infection. IL-3, like granulocyte-macrophage colony-stimulating factor (GM-CSF), is produced by activated but not resting T cells, but although GM-CSF is constitutively expressed in HTLV-infected T cells IL-3 mRNA cannot be detected in either unstimulated or mitogen-stimulated HTLV-infected cells by polymerase chain reaction (PCR) analysis. In contrast, transient co-transfection studies with an IL-3 promoter-CAT reporter gene and an HTLV-II Tax expression construct demonstrate that Tax can transactivate the IL-3 promoter in HTLV-uninfected T cells. To determine whether differences in IL-3 promoter-binding proteins present in HTLV-infected and uninfected T cells account for this discrepancy, DNAase I footprinting of the IL-3 promoter was performed. Although crude nuclear extracts from both cell types protected the IL-3 sequences located between base pairs -168 and -125, the sequences between -125 and -103, which contain the lymphokine consensus sequences CK-1 and CK-2, were protected by extracts from HTLV-infected but not HTLV-uninfected T cells. Deletion of the region containing the CK-1 and CK-2 sequences from an IL-3 promoter CAT construct resulted in a sixfold rise in promoter activity in HTLV-infected but not uninfected T-cell lines, indicating that this region participates in the repression of IL-3 gene expression in HTLV-infected T cells.

Impact of a targeted asthma intervention program on treatment costs in patients with asthma.

OBJECTIVE: To evaluate the impact of a targeted asthma intervention on treatment costs, utilization of medical services, number of prescription drugs filled, and trends of medication use from a third-party perspective. STUDY DESIGN: Longitudinal population-based study. METHODS: Study asthmatic patients were classified into intermittent and persistent asthma groups according to the Health Plan Employer Data and Information Set (HEDIS) 2000 asthma measurement. The intervention instituted appropriate asthma drug therapy according to National Heart, Lung, and Blood Institute guidelines. A paired t test and analysis of covariance were used to compare treatment costs and the number of prescriptions dispensed in the 9 months before and the 9 months after the intervention. RESULTS: The study patients (n = 1616) included 566 with intermittent asthma and 1050 with persistent asthma. After the intervention, treatment costs per patient increased significantly by $122 in the intermittent asthma group (P = .001) but decreased significantly by $247 in the persistent asthma group (P < .001). Costs incurred by patients with persistent asthma decreased by $149 for hospitalization (P = .003), $16 for emergency room visits (P < .001), $82 for physician visits (P < .001), and increased by $1 for asthma medications (P = .938). The number of asthma medication prescriptions per patient increased by 0.72 prescriptions in the intermittent asthma group (P < .001), whereas the persistent asthma group had a per patient reduction of 0.99 prescriptions (P < .001). CONCLUSION: A targeted asthma intervention resulted in decreased hospitalization, emergency room, and physician visit costs in patients with persistent asthma.

Serum C-reactive protein: a predictor of mortality in continuous ambulatory peritoneal dialysis patients.

OBJECTIVE: To evaluate the predictive value of a single baseline serum C-reactive protein (sCRP) as a marker of mortality in continuous ambulatory peritoneal dialysis (CAPD) patients. DESIGN: A review of prospectively collected data in a 2-year follow-up study. SETTING: Tertiary medical center. PATIENTS: The study included 106 patients who were stable and had been on CAPD for a minimum of 3 months. MAIN OUTCOME MEASURES: Patient survival rate was the main outcome measure of this study. Other outcome measures were technique survival rate, peritonitis rate, and hospitalized days. Covariables used in the survival analysis were age, sex, the presence of cardiovascular disease or diabetes mellitus, sCRP, serum albumin, hematocrit, cholesterol, HDL-cholesterol, malnutrition by subjective global assessment (SGA), weekly Kt/V urea, and weekly standardized creatinine clearance (SCCr). RESULTS: The 2-year patient survival rate was significantly lower in the increased sCRP group than in the normal sCRP group (66.7% vs 94.1%, p = 0.001), although there was no significant difference in technique failure, peritonitis rate, and hospitalized days between the two groups. By Cox proportional hazards analysis, independent predictors of mortality were: cardiovascular disease (relative risk, RR = 8.96, p < 0.005); increased sCRP level (RR = 1.19, p < 0.05); and high hematocrit (RR = 1.18, p < 0.05). CONCLUSION: Serum CRP at enrollment is an independent predictor of 2-year patient survival in CAPD patients.

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.

Renal osteodystrophy in pre-dialysis patients: ethnic difference?

The purpose of the present study is to investigate whether an ethnic difference exists in the incidence of renal osteodystrophy between Asian and Western countries in end-stage renal disease (ESRD) patients. We evaluated bone histology in 58 pre-dialysis patients (28 male, 30 female; mean age: 47.7 years). All patients had bone biopsies with quantitative histomorphometry and serological parameters such as intact PTH, osteocalcin, total alkaline phosphatase, and basal and deferoxamine-stimulated serum aluminum levels. We observed that 91.4% of all evaluated patients showed renal osteodystrophy before the start of dialytic therapy. Mild osteitis fibrosa were observed in 21 patients (36.2%), severe osteitis fibrosa in 5 patients (8.6%), mixed lesions in 7 patients (12.1%), osteomalacia in 6 patients (10.3%), aplastic bone disease in 14 patients (24.1%), and normal bone in 5 patients (8.6%). Among the bone histomorphometric parameters, fibrosis area rate (%) showed the best correlation with intact PTH, and osteocalcin and osteoid area rate (%) with total alkaline phosphatase. Aluminum-related bone disease was not observed. Among patients with aplastic bone disease, only 14.3% showed aluminum deposition of any significance (5% < stainable bone surface aluminum < 25%). In the diabetic patients, aplastic bone disease was most common, but no case was related to aluminum intoxication. In conclusion, the distribution of renal osteodystrophy in our study was different from that of Western countries in pre-dialysis patients. Our patients tended to have more mild-form osteitis fibrosa and normal findings, and less severe-form osteitis fibrosa and aplastic bone disease. Aluminum-related bone disease was not observed.

Risk factors influencing the decline of residual renal function in continuous ambulatory peritoneal dialysis patients.

OBJECTIVE: To assess the nature of the decline in residual renal function (RRF) after the initiation of peritoneal dialysis, and to identify risk factors influencing the preservation of RRF. DESIGN: A retrospective single-center study. SETTING: Tertiary medical center. PATIENTS: Eighty patients who were clinically stable and had been on continuous ambulatory peritoneal dialysis (CAPD) for a minimum of 6 months. MAIN OUTCOME MEASURES: All subjects had at least three measurements of RRF, which was calculated as the average of creatinine clearance (Ccr) and urea clearance from a 24-hour urine collection. All measurements of RRF were plotted on a logarithmic scale and a linear scale against the duration of CAPD. Covariables used in the correlation analyses were age, sex, the presence of diabetes mellitus, mean blood pressure, mean diastolic blood pressure, hematocrit and Ccr at the start of peritoneal dialysis, peritoneal membrane transport characteristics by peritoneal equilibration test (PET), and the rate of peritonitis. RESULTS: A significant correlation was found between CAPD duration and RRF decline represented on a logarithmic scale with a correlation coefficient (r) of 0.355 (p < 0.001). In contrast, on a linear scale, the correlation coefficient was only 0.273 (p < 0.01). By linear multiple regression analysis, the only independent risk factor for the decline of RRF was the rate of peritonitis (r = -0.446, p < 0.001). CONCLUSION: These results suggest that RRF declines exponentially rather than linearly with time, and that the rate of peritonitis is an independent risk factor for the decline of RRF in CAPD patients.

The changing patterns of liver abscess during the past 20 years--a study of 482 cases.

The diagnostic and treatment modalities of liver abscess have developed rapidly over the past few years but morbidity and mortality has not been markedly reduced. A total of 482 cases of liver abscess admitted to the Yonsei Medical Center over the past 20 years (Jan. 1971-Dec. 1990) were divided into 261 cases from the 1970s and 221 cases from the 1980s and the clinical and laboratory parameters were analyzed comparatively to determine if the clinical features, therapies and prognosis of liver abscess had changed. The proportion of amebic relative to pyogenic liver abscess decreased. Transbiliary infections increased in pyogenic liver abscess of the 1980s. Clinical signs such as jaundice and hepatomegaly and symptom duration before admission decreased. Abnormal laboratory features including hypoalbuminemia and elevation of alkaline phosphatase decreased and increased, respectively, in the 1980s. Ultrasonically guided percutaneous aspiration was the choice of treatment instead of surgical drainage in the 1980s. Despite diagnostic and therapeutic advances in the management of liver abscess, the prognosis has not improved in the 1980s as compared to the 1970s. This may reflect an increase in the incidence of liver abscess in old aged patients and patients with diabetes mellitus or underlying malignancy in the 1980s.

Interleukin-1 beta, -6 and interferon-gamma productions in patients undergoing continuous ambulatory peritoneal dialysis.

In order to investigate cytokine productions in patients undergoing continuous ambulatory peritoneal dialysis (CAPD), we studied the production of interleukin (IL)-1 beta, -6 and interferon (IFN)-gamma by cultured peripheral blood mononuclear cells (PBMC) in peritonitis-free CAPD patients. The correlation of cytokine production with plasma parathyroid hormone (PTH) and albumin levels was also evaluated. While the release of IL-1 beta was not markedly different from controls release of IL-6 from 24-hour cultured PBMCs was significantly greater than that of controls, (Mean +/- S.D., IL-6: 2186.8 +/- 1217.9 pg/ml, vs 1516.3 +/- 767.9, p < 0.05). The addition of lipopolysaccharide (LPS, 10 micrograms/ml, significantly stimulated IL-1 beta and -6 production of PBMCs in CAPD patients and controls, compared to an unstimulated condition. The LPS-induced IL-1 beta production was also not markedly different from controls, whereas LPS-induced IL-6 production was significantly higher than controls (IL-6: 13,220.7 +/- 7177.4 vs 7411.4 +/- 1236.9, p < 0.05). However, the percentage increases of IL-6 production stimulated with LPS in CAPD patients were not significantly different from controls (p > 0.05). No difference of baseline IFN-gamma was detected between CAPD patients controls, but phytohemagglutinin (PHA, 10 micrograms/ml)-stimulated IFN-gamma release was significantly higher in CAPD patients than controls (2425.9 +/- 1565.0 pg/ml vs 1364.0 +/- 755.1, p < 0.05). There was no significant correlation between PTH and, IL-1 beta, serum albumin level and LPS-stimulated IL-6 production (r = 0.54, p < 0.05). In conclusion, CAPD seems to partly induce activation of PBMCs with an enhanced release of IL-6 and IFN-gamma, and CAPD patients with higher serum albumin levels tend to show higher IL-6 production in immune response.