Global longitudinal strain to predict myocardial fibrosis in patients in carbon monoxide poisoning

Background

Carbon monoxide (CO) inhibits oxygen delivery and subsequently causes ischemic changes that can lead to myocardial damage. Late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR) reflects myocardial fibrosis and detects subclinical myocardial damage in patients with acute CO poisoning. However, CMR is expensive and hard to perform in patients with neurologic deficit. Therefore, this study aims to investigate which echocardiographic parameters could predict the presence of myocardial fibrosis represented by LGE in CO intoxication patients.

Methods

This prospective observational study included 128 consecutive patients (Mean age: 52.2±16.2) with acute CO poisoning and elevated troponin I (defined as >0.045 ng/mL) at the emergency department of a tertiary university hospital. All participants underwent hyperbaric oxygen therapy (HBOT). CMR and conventional echocardiography with 2D speckle-tracking were performed within 7 days. Subjects were categorized into late gadolinium enhancement (LGE) and no LGE group according to the CMR findings.

Results

Mean left ventricular (LV) ejection fraction (EF) and global longitudinal strain (GLS) were 57.0±10.0% and −16.3±3.7% respectively. LGE was observed in 89 (69.5%) patients and the most common pattern was mid-wall involvement. Clinical characteristics such as age, sex, shock, time elapsed from rescue to HBOT, and the level of troponin I were not different between groups with LGE and without LGE. Among echocardiographic parameters, LV EF was not significantly different between groups (LGE: 56.0±10.5% vs 59.3±8.1%, p=0.089). LV GLS was more impaired in patients with LGE compared to those without LGE (−15.7±3.8% vs −17.9±3.0%, p=0.003). In multivariate logistic analysis, LV GLS was independently associated with the presence of LGE [Odds ratio (OR) 1.279, 95% confidence interval (CI) (1.047–1.563), p=0.016], but not LV EF.

Conclusion

In patients with acute CO poisoning and elevated troponin I, LV GLS predicted the presence of LGE in CMR. These finding suggest that subclinical myocardial dysfunction represented by LV GLS may reflect the burden of CO induced myocardial fibrosis.

Funding Acknowledgement

Type of funding sources: None.

Efficacy and Safety of Treatment with Quadruple Oral Hypoglycemic Agents in Uncontrolled Type 2 Diabetes Mellitus: A Multi-Center, Retrospective, Observational Study

BACKGROUND

Only few studies have shown the efficacy and safety of glucose-control strategies using the quadruple drug combination. Therefore, the aim of the present study was to investigate the usefulness of the quadruple combination therapy with oral hypoglycemic agents (OHAs) in patients with uncontrolled type 2 diabetes mellitus (T2DM).

METHODS

From March 2014 to December 2018, data of patients with T2DM, who were treated with quadruple hypoglycemic medications for over 12 months in 11 hospitals in South Korea, were reviewed retrospectively. We compared glycosylated hemoglobin (HbA1c) levels before and 12 months after quadruple treatment with OHAs. The safety, maintenance rate, and therapeutic patterns after failure of the quadruple therapy were also evaluated.

RESULTS

In total, 357 patients were enrolled for quadruple OHA therapy, and the baseline HbA1c level was 9.0%±1.3% (74.9±14.1 mmol/mol). After 12 months, 270 patients (75.6%) adhered to the quadruple therapy and HbA1c was significantly reduced from 8.9%±1.2% to 7.8%±1.3% (mean change, -1.1%±1.2%; P<0.001). The number of patients with HbA1c <7% increased significantly from 5 to 68 (P<0.005). In addition, lipid profiles and liver enzyme levels were also improved whereas no changes in body weight. There was no significant safety issue in patients treated with quadruple OHA therapy.

CONCLUSION

This study shows the therapeutic efficacy of the quadruple OHA regimen T2DM and demonstrates that it can be an option for the management of T2DM patients who cannot use insulin or reject injectable therapy.

Immune response to hepatitis B vaccination and factors associated with poor immune response among healthcare workers

Background

Hepatitis B virus (HBV) infection is a major global health problem, and healthcare workers (HCWs) are at high risk for HBV infection. Current guidelines strongly recommend immunization and screening for high-risk groups.

Aims

We evaluated immunization and screening for HBV vaccination, assessed post-vaccination immune status of HCW's and characterized potential risk factors associated with poor immune response.

Materials and Methods

From January 2010 to December 2018, we retrospectively analyzed comprehensive health checkup data for a total of 303 HCWs who received an HBV vaccination. After vaccination, HBV surface antibody (anti-HBs) titers were collected and the distribution of immune response types was determined. Risk factors for poor immune responses were identified using logistic regression.

Results

A total of 213 HCWs were analyzed after exclusion based on the exclusion criteria. In total, 28 (13.2%) HCWs had anti-HBs titers <100 mIU/mL (hyporesponsive/nonresponsive groups), and 185 (86.8%) had anti-HBs titers ≥100 mIU/mL (hyperresponsive group). Follow-up observations found that 75% (21/28) of the hyporesponsive/nonresponsive groups did not have increased anti-HBs titers or did not maintain an increased response. A multivariate analysis showed that HBV antibody titers at the time of employment were a significant risk factor (OR, 6.12; CI, 1.34-27.93; P = 0.019).

Conclusions

More attention should be paid to groups that are hyporesponsive/nonresponsive after vaccination and to those with low anti-HBs titers at the beginning of employment. HCWs can be further protected from HBV if their results are discussed at postvaccination follow-ups.

Risk factors of malignant fluorodeoxyglucose-avid lymph node on preablation positron emission tomography in patients with papillary thyroid cancer undergoing radioiodine ablation therapy

F-18 fluorodeoxyglucose (FDG)-avid metastatic lesions are associated with a poor response to radioiodine ablation therapy (RIT) in papillary thyroid cancer (PTC). This study evaluated the significance of preablative FDG positron emission tomography (PET) for the assessment of risk factors and frequency of malignant FDG-avid lymph nodes in patients with PTC undergoing RIT.The study included 339 consecutive patients (mean age 46.3 ± 12.5 y; 260 females) with PTC referred for the first RIT and who underwent routine preablative FDG PET between April 2011 and February 2013. FDG-avid lymph nodes (FALNs) were identified using retrospective image reviews. The frequency of malignant FALN (mFALN), its contribution to persistent or recurrent PTC, and its risk factors were analyzed.Among the patients, 112 had FALNs (33.0%): 11 mFALNs (3.2%) and 101 benign FALNs (bFALNs, 29.8%). mFALN contributed to 55% of persistent or recurrent PTC after RIT, which was observed in 20 of 339 patients (5.9%) during the post-RIT follow-up. Among preoperative risk factors, suspicious extrathyroidal extension and lateral neck lymph node metastasis on imaging studies were associated with mFALN. Among postoperative risk factors, T3/T4 and N1b stages, higher stimulated thyroglobulin, and higher numbers of metastatic lymph nodes and dissected lymph nodes, were associated with mFALN.mFALNs were observed in a small number of patients with PTC undergoing RIT, but it contributed 55% of total recurrent or persistent disease. Increased frequency of mFALNs is associated with more advanced PTC. Preablative FDG PET has value in evaluation of patients with RIT-resistant lesions and may help determine further treatment strategies.

Preparation for radioactive iodine therapy is not a risk factor for the development of hyponatremia in thyroid cancer patients

The aim of this study was to evaluate whether the preparation for radioactive iodine (RAI) therapy by thyroid hormone withdrawal (THW) or a low-iodine diet (LID) can be risk factors for the development of hyponatremia in patients with differentiated thyroid cancer after thyroidectomy.We retrospectively reviewed the medical records and laboratory findings of 326 patients who underwent preparation for RAI therapy after thyroidectomy from 2012 to 2014. Demographic and clinical variables including the method of thyrotropin stimulation and duration of LID were assessed. Serum sodium was measured twice, before operation and before RAI therapy.Hyponatremia was detected in only 3 patients (0.9%) before operation, but in 15 patients (4.6%) before RAI therapy. None of the patients had severe hyponatremia after preparation for RAI therapy. Pre-RAI therapy serum sodium was correlated with the method of thyrotropin stimulation (TWH vs recombinant human thyroid stimulating hormone, P = 0.014) and duration of LID (r = -0.131, P = 0.018); however, the preparation of RAI therapy, THW and LID, did not affect the development of hyponatremia in logistic regression analysis. Preoperative serum sodium was a significant risk factor for hyponatremia during preparation for RAI therapy.Preparation for RAI therapy by THW or LID is not a risk factor for the development of hyponatremia in patients with thyroid cancer. The development of hyponatremia was neither frequent nor severe during preparation for RAI therapy. Physicians should not be greatly concerned about rare life-threatening hyponatremia during preparation for RAI therapy.

Association of meal frequency with metabolic syndrome in Korean adults: from the Korea National Health and Nutrition Examination Survey (KNHANES)

BACKGROUND

Although previous studies have established a close relationship between caloric intake and metabolic syndrome, there is limited research exploring the impact of meal frequency adjusted by caloric intake on metabolic syndrome (MetS).

OBJECTIVE

To evaluate the association of meal frequency and MetS after adjusting for confounding factors including caloric intake in Korean men and women.

METHODS

We analyzed the national representative data of a total 12,389 adults (5171 men, 7218 women) from the Korean National Health and Nutrition Examination Survey (KNHANES) 2010-2012. Subjects were categorized as eating 3 meals/day (MF3) or 2 or fewer meals/day (MF ≤ 2). Daily caloric intake was calculated using CAN-Pro 4.0 (The Korean Nutrition Society, Seoul, Korea).

RESULTS

The prevalence of components of MetS differed significantly according to meal frequency in both men and women. In an unadjusted analysis, the prevalence of MetS in women was significantly higher in the MF3 group than the MF ≤ 2 group (27.5% vs. 17.8%, P < 0.001), whereas the prevalence of MetS in men did not differ between the MF3 and MF ≤ 2 groups (24.6% vs. 22.7%, P = 0.281). However, after adjusting for age, caloric intake, smoking status, alcohol consumption, physical activity, income, and education level, men in the MF ≤ 2 group had an increased risk of metabolic syndrome compared to men in the MF3 group (OR = 1.37, 95%, CI = 1.12-1.67). On the other hand, meal frequency did not affect the risk of metabolic syndrome in women after adjusting for confounding factors including caloric intake (OR = 1.09, 95%, CI = 0.90-1.31).

CONCLUSIONS

This study suggests that lower meal frequency adjusted for caloric intake, physical activity, age, smoking, alcohol, income, and education may be associated with increased risk of MetS in Korean men.

Plasma neutrophil gelatinase-associated lipocalin levels are positively associated with diabetic retinopathy in patients with Type 2 diabetes

AIM

To assess the relationship between plasma neutrophil gelatinase-associated lipocalin (NGAL) levels and diabetic retinopathy in patients with Type 2 diabetes.

METHODS

In total, 204 patients with Type 2 diabetes were investigated in this cross-sectional study. They were classified as having no diabetic retinopathy, non-proliferative diabetic retinopathy (NPDR) or proliferative retinopathy (PDR), according to the degree of diabetic retinopathy. Thus, diabetic retinopathy in the patients in this study was either NPDR or PDR.

RESULTS

Plasma NGAL concentrations were significantly higher in patients with diabetic retinopathy than in those without. The mean plasma NGAL levels differed significantly according to the severity of diabetic retinopathy (no diabetic retinopathy, 120.8 ng/ml; NPDR, 217.8 ng/ml; PDR, 372.4 ng/ml; P for trend = 0.002) after adjustment for other covariates. In multivariable analysis, plasma NGAL levels were significantly associated with diabetic retinopathy (odds ratio for each standard deviation increase in the logarithmic value, 7.75; 95% confidence interval, 2.04-29.41, P = 0.003).

CONCLUSION

Plasma NGAL levels were positively associated with diabetic retinopathy in patients with Type 2 diabetes.

Serum bilirubin concentrations are positively associated with serum C-peptide levels in patients with Type 2 diabetes

AIMS

To investigate the relationship between physiological serum total bilirubin concentrations and serum C-peptide levels in Korean patients with Type 2 diabetes.

METHODS

A total of 588 patients with Type 2 diabetes were investigated in this cross-sectional study. Fasting C-peptide level, 2-h postprandial C-peptide level and ΔC-peptide (postprandial C-peptide minus fasting C-peptide) level were measured in all patients.

RESULTS

Fasting C-peptide level, postprandial C-peptide level and ΔC-peptide level tended to be higher in patients with higher bilirubin concentrations. Partial correlation analysis showed that serum bilirubin levels were significantly correlated with fasting C-peptide level (r = 0.159, P < 0.001), postprandial C-peptide level (r = 0.209, P < 0.001) and ΔC-peptide level (r = 0.186, P < 0.001) after adjustment for other covariates. In the multivariate model, the association between serum bilirubin concentrations and serum C-peptide levels remained significant after adjustment for confounding factors including age, gender, familial diabetes, hypertension, hyperlipidaemia, BMI, HbA1c , duration of diabetes and associated liver function tests (fasting C-peptide level: β = 0.083, P = 0.041; postprandial C-peptide level: β = 0.106, P = 0.005; ΔC-peptide level: β = 0.096, P = 0.015, respectively).

CONCLUSIONS

Serum bilirubin concentrations within the physiological range were positively associated with serum C-peptide levels in patients with Type 2 diabetes.

Physiological serum bilirubin concentrations are inversely associated with the prevalence of cardiovascular autonomic neuropathy in patients with Type 2 diabetes

AIMS

Although severe hyperbilirubinaemia causes kernicterus in neonates, normal to modestly elevated bilirubin concentrations have been reported to be neuroprotective. However, the relationship between serum bilirubin concentrations and cardiovascular autonomic neuropathy in patients with Type 2 diabetes is currently unknown. This study assessed the relationships between physiological serum total bilirubin concentrations and cardiovascular autonomic neuropathy in patients with Type 2 diabetes.

METHODS

A total of 2991 patients with Type 2 diabetes were investigated in this cross-sectional study. Cardiovascular autonomic neuropathy was diagnosed by a cardiovascular reflex test. According to the American Diabetes Association criteria, the degree of cardiovascular autonomic dysfunction was graded into normal, early, definite and severe. Cardiovascular autonomic neuropathy was either definite or severe in the present study. An analysis of covariance after adjustment for other covariates was performed. A logistic regression model was used to assess an association of cardiovascular autonomic neuropathy with serum total bilirubin tertiles.

RESULTS

Serum total bilirubin concentrations were significantly lower in subjects with cardiovascular autonomic neuropathy. The mean total bilirubin values differed significantly according to the severity of cardiovascular autonomic dysfunction (normal 13.0 μmol/l; early 12.3 μmol/l; definite 11.8 μmol/l; severe 10.1 μmol/l; P for trend < 0.001) after adjustment for other covariates. In multivariate analysis, serum total bilirubin levels were significantly associated with cardiovascular autonomic neuropathy (odds ratio 0.36; 95% CI 0.21-0.63 for the highest vs. the lowest bilirubin tertile, P < 0.001).

CONCLUSIONS

Serum total bilirubin concentrations within the physiologic range are inversely associated with the prevalence of cardiovascular autonomic neuropathy in patients with Type 2 diabetes.

P5-14-02: Clinicopathologic and Prognostic Difference of Screen Detected Breast Cancer Compared with Symptomatic Breast Cancer

Background: Breast cancer screening program makes it possible to detect early cancer, thus to reduce breast cancer mortality. The authors studied clinicopathologic characteristics and prognosis of screen detected invasive breast cancer compared with symptomatic breast cancer. Furthermore, we compared the result according to molecular subtypes (luminal A, luminal B, Her2, triple negative), so intended to identify the role of screening in each subtypes. Material and Methods: From January 2002 to June 2008, 3141 patients who underwent operation for the treatment of invasive ductal carcinoma(NOS) at Samsung medical center were included. Among them, 1025 patient were screen detected, 2116 patient were symptomatic, out of screening over 2 years. We reviewed the medical records retrospectively.

Result: Screen detected breast cancer was associated with older patients, smaller tumor size, more hormone receptor- positive, less lymph node involvement, lower stage and reduced mortality compared with symptomatic breast cancer (P &lt; .001). According to the molecular subtype, in luminal A subtype, the result shows better pathologic feature and also favorable overall and recur-free survial significantly.

P5-14-19: Ipsilateral Breast Tumor Recurrence Prediction with Web-Based Normogram in Korea

Purpose Ipsilateral Breast Tumor Recurrence(IBTR!) 2.0 is web-based tool which predict the ten years risk of local recurrence after breast conserving theraphy. This tool integrates seven prognostic factors (patient age, margin status, lymphovascular invasion, tumor size, tumor grade, use of chemotherapy and hormonal therapy) for local recurrence with or without radiation theraphy. To validate IBTR! 2.0 for Korean breast cancer patients, Samsung Medical Center database was used between 1994 and 2001.

Methods The IBTR! 2.0 nomogram was tested against 358 patients who underwent breast conserving surgery with radiation theraphy from Samsung Medical Center between 1994 and 2001. The individual dadabase which was entered into IBTR! 2.0 computer model generate predictive local recurrence rate. The mean predicted and observed 10-year estimates were compared for the entire cohort and for four groups predefined by nomogram-predicted risks: group 1: less than 3%; group 2: 3% to 5%; group 3: 5% to 10%; and group 4: more than 10%.

Results IBTR! version 2.0 predicted an overall 10-year IBTR estimate of 5.5% (95% CI, 5.2 to 5.9), while the observed estimate was 7.69% (20 IBTR cases in 358 patients, 95% CI, 1.6 to 9.3; P=0.59).

The predicted and observed IBTR estimates were: group 1 ( 2 cases in 67 patients): 2.3% versus 2.9%, P=0.53; group 2 (2 cases in 124 patients)): 3.9% versus 4.1%, P=0.18; group 3 (14 cases in 139 patinets): 7.3% versus 4.8%, P=0.13; and group 4 (2 cases in 28 patients): 12.15% versus 7.1%, P=0.61.

Conclusion IBTR! 2.0 is acceptable nomogram for predicting 10 years local recurrence using Samsung medical Center database. This nomogram showed overestimation in group 3, 4, however did not showed statistical differences. This nomogram may assist patient counseling and medical decision making, but prior to using whole Korean patients, this model requires validation with multiple Korean sources.

References

1. Fisher, B., et al., Twenty-year follow-up of a randomized trial comparing total mastectomy, lumpectomy, and lumpectomy plus irradiation for the treatment of invasive breast cancer. N Engl J Med, 2002. 347 (16): p. 1233–41.

2. Liljegren, G., et al., 10-Year results after sector resection with or without postoperative radiotherapy for stage I breast cancer: a randomized trial. J Clin Oncol, 1999. 17 (8): p. 2326–33.

3. Anderson, S.J., et al., Prognosis after ipsilateral breast tumor recurrence and locoregional recurrences in patients treated by breast-conserving therapy in five National Surgical Adjuvant Breast and Bowel Project protocols of node-negative breast cancer. J Clin Oncol, 2009. 27 (15): p. 2466–73.

4. Sanghani, M., et al., Predicting the Risk of Local Recurrence in Patients With Breast Cancer. American Journal of Clinical Oncology, 2007. 30 (5): p. 473–480.

5. Sanghani, M., et al., Validation of a Web-Based Predictive Nomogram for Ipsilateral Breast Tumor Recurrence After Breast Conserving Therapy. Journal of Clinical Oncology, 2010. 28 (5): p. 718–722.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-14-19.

A case of xanthoma disseminatum with spontaneous resolution over 10 years: review of the literature on long-term follow-up

Xanthoma disseminatum (XD) is a rare and potentially progressive non-Langerhans-cell histiocytosis. To date, a few cases of XD with spontaneous complete resolution have been described. The present report describes a 16-year-old girl who presented with yellow to red-brown papules and nodules on her eyelids, cheeks, axillae, back and buttocks. Indirect laryngoscopy showed multiple xanthomatous plaques on the larynx, posterior pharynx, epiglottis, and vocal cords. Additional findings were polyuria, polydipsia, and amenorrhea. Skin biopsy and electron microscopy results confirmed the diagnosis of XD. The patient was treated with fenofibrate, simvastatin, desmopressin, and sex-hormone replacement therapy. Her skin lesions began to slowly fade 6 years after disease onset, eventually resolving spontaneously and completely, but leaving an atrophic scar, frank anetoderma, and persisting diabetes insipidus. This case report together with a review of the English-language literature on the long-term follow-up of XD patients provides additional information on the natural history of this disease.

Abstract P3-10-25: The Prognosis of Metaplastic Breast Cancer Patients Compare to Triple-Negative Breast Cancer Patients

Background: Metaplastic breeast cancer (MBC) is a rare, heterogenous cancer characterized by admixture of adenocarcinoma with metaplastic elements, low hormone receptor expression and poor outcome. This study was planned to assess the clinicopathological chacteristics and immunohistochemical findings of MBC compared to invasive ductal carcinoma (IDC) including the triple-negative subtype (TN-IDC). Material and Methods: We retrospectively reviewed the medical records of 47 MBC and 1,346 IDC patients. Two hundred eighteen TN-IDC patients were included in the 1,346 IDC patients. Between 2005 and 2009, these patients were undergone surgical treatment at the Samsung Medical Center. Patients were reviewed clinicopathologic factors, immunohistochemistry of biologic factors such as ER, PR, HER-2, p53, Ki67, cytokeratine (CK) 5/6, epidermal growth factor receptor (EGFR), and treatment modalities (type of operation, use of chemotherapy, radiotherapy and hormone therapy). Result: The MBC patients presented with a larger tumor size (&gt;T1, 66.0% vs. 44.3.%, P = 0.008), lower lymph node involvement (N0, 73.3% vs. 55.6%, P = 0.03), higher histologic (HG) and nuclear grade (NG) (HG3, 70.0% vs. 41.5%, P = 0.001; NG3,82.6% vs. 46.9%, P &lt; 0.001), fewer estrogen receptor (ER), progesterone receptor (PR) and HER2 positivity (ER+, 4.3% vs. 69.2%, P &lt; 0.001; PR+, 6.4% vs. 63.5%, P &lt; 0.001; HER2+, 0% vs. 27.6%, P &lt; 0.001), higher p53, CK5/6 and EGFR expression (p53+, 63.8% vs.38.8%, P &lt; 0.001; CK5/6+, 71.9% vs.21.5%, P &lt; 0.001; EGFR+, 93.9% vs.21.6%, P &lt;0.001) and more TN subtypes (93.6% vs. 16.2%, P &lt; 0.001) compared to the IDC group. There was no significant difference in clinicopathological characteristics with MBC and TN-IDC except EGFR over expression (EGFR+, 93.9% vs.69.0%, P = 0.017). In follow-up duration (median 30 months, range 2-56 months), seven (14.9%) MBC patients and 98 (7.2%) IDC patients recurred. The 3-year disease-free survival (DFS) rate was 78.1% in the MBC group and 91.1% in IDC group (P &lt;0.001). The 3-year DFS rate was not significantly difference between MBC group and TN-IDC group (78.1% vs. 84.9%, P = 0.114). However, in patients with lymph node metastasis who underwent adjuvant chemotherapy, the 3-year DFS rate was 44.4% in MBC group and 72.5% in TN-IDC group (P = 0.025).

Discussion: In our result, MBC show poorer clinical outcome than IDC. It is not shown significant difference between MBC and TN-IDC. However, MBC patients with nodal metastasis have poorer prognosis than TN-IDC patients with metastasis despite adjuvant chemotherapy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-10-25.

Effect of glycolic acid on UVB-induced skin damage and inflammation in guinea pigs

OBJECTIVES

Recently the use of glycolic-acid-containing cosmetics has received increased public interest in their supposed ability to reduce wrinkles, roughness, age spots and other skin damage. However, the safety of such products when used excessively or chronically, especially by photosensitive people, is being questioned. The purpose of this study was to examine the effects of glycolic acid alone or in combination with UVB on skin damage and inflammatory response.

METHOD

Guinea pigs were treated with glycolic acid (from 1 to 7 mg/cm(2)) alone or in combination with UVB (0.4 or 3 J/cm(2)) for 14 days. Skin damage was evaluated by scoring the skin irritation value by the method of Draize and by histopathological observations. Cyclooxygenase 2 (COX-2) expression and prostaglandin E(2) (PGE(2)) production were also assessed.

RESULTS

Glycolic acid caused an increase in the level of skin damage in a dose- and time-dependent manner. Lower doses (1 and 3 mg/cm(2)) of glycolic acid mostly caused erythema and eschar, and these consequently formed scales, whereas higher doses (5 and 7 mg/cm(2)) of glycolic acid caused redness, edema and necrotic ulceration. Glycolic acid also increased the thickness of the epidermal layer, reduced the organization of the stratum corneum and eventually destroyed some parts of the epidermal layer at 7 mg/cm(2). UVB (0.4 and 3 J/cm(2)) caused redness and edema as well as reduced the integrity of the stratum corneum. Glycolic acid enhanced the UVB-induced skin damage. The magnitude of the damage caused by combined UVB and glycolic acid treatment was much greater than that caused by glycolic acid or UVB alone. Moreover, partial destruction of the epidermal layer was observed in skin treated with 3 J/cm(2) UVB and 3 mg/cm(2) glycolic acid. However, glycolic acid did not change the basal and UVB-induced PGE(2) production and COX-2 protein expression.

CONCLUSION

These results show that glycolic acid causes skin damage in a dose- and time-dependent manner and that it enhances UVB-induced skin damage without accompanying PGE(2) production or COX-2 protein expression. Therefore, caution should be exercised by those using glycolic acid on a chronic basis or excessively. Moreover, those with photosensitive skins and those more exposed to the sun should be particularly careful.

Enhanced IL-18 expression in common skin tumors

Interleukin-18 (IL-18) has been found to have multiple effects upon various cells involved in inflammatory response. Recently we reported that B16 murine melanoma cells are able to produce IL-18, which is involved in the regulation of intracellular reactive oxygen intermediates (ROI) and Fas-ligand expression, indicating that IL-18 plays key role in the tumor activity of melanoma. In this study, we investigated the pattern of IL-18 expression in the human system. IL-18 production was tested by enzyme linked immunosorbent assay (ELISA) assay in various tumor cell lines, including Raji (Burkitt's lymphoma), IM-9 (B lymphoblast), Jurkat (acute T cell leukemia), SK-MES-1 (squamous cell carcinoma (SCC) cell line), SK-MEL-2, G-361, DM-4, and DX-3 (melanoma cell lines). ELISA tests showed that IL-18 was highly expressed in malignant skin tumors such as SK-MES-1, SK-MEL-2, G-361, DM-4, and DX-3 cell lines, thus suggesting that IL-18 production may be associated with the malignancy of skin tumors. Here, we report that enhanced IL-18 expression is positively correlated with malignant skin tumors such as SCC and melanoma, suggesting the importance role of IL-18 in malignancy of skin tumors. Taken together, expression of IL-18 by tumor cells in human skin tissue may provide an important clue to understand the pathogenesis of malignant skin tumors.

Synthesis and characterization of a novel extracellular polysaccharide by Rhodotorula glutinis

The aim of this work was to characterize an exopolysaccharide by Rhodotorula glutinis KCTC 7989 and to investigate the effect of the culture conditions on the production of this polymer. The extracellular polysaccharide (EPS) produced from this strain was a novel acidic heteropolysaccharide composed of neutral sugars (85%) and uronic acid (15%). The neutral sugar composition was identified by gas chromatography as mannose, fucose, glucose, and galactose in a 6.7:0.2:0.1:0.1 ratio. The molecular weight of purified EPS was estimated to be 1.0-3.8 x 10(5) Dalton, and the distribution of the molecular weight was very homogeneous (polydispersity index = 1.32). The EPS solution showed a characteristic of pseudoplastic non-Newtonian fluid at a concentration >2.0% in distilled water. The maximum EPS production was obtained when the strain was grown on glucose (30 g/L). Ammonium sulfate was the best suitable nitrogen source for EPS production. The highest yield of EPS was obtained at a carbon to nitrogen ratio of 15. The EPS synthesis was activated at the acidic range of pH 3.0-5.0 and increased when the pH of the culture broth decreased naturally to <2.0 during the fermentation. When the yeast was grown on glucose (30 g/L) and ammonium sulfate (2 g/L) at 22 degrees C at an initial pH of 4.0, EPS production was maximized (4.0 g/L), and the glucose-based production yield coefficient and carbon-based production yield coefficient were 0.30 g of EPS/g of glucose and 0.34 g (carbon of EPS)/g (carbon of glucose), respectively.

CTCF-binding sites flank CTG/CAG repeats and form a methylation-sensitive insulator at the DM1 locus

An expansion of a CTG repeat at the DM1 locus causes myotonic dystrophy (DM) by altering the expression of the two adjacent genes, DMPK and SIX5, and through a toxic effect of the repeat-containing RNA. Here we identify two CTCF-binding sites that flank the CTG repeat and form an insulator element between DMPK and SIX5. Methylation of these sites prevents binding of CTCF, indicating that the DM1 locus methylation in congenital DM would disrupt insulator function. Furthermore, CTCF-binding sites are associated with CTG/CAG repeats at several other loci. We suggest a general role for CTG/CAG repeats as components of insulator elements at multiple sites in the human genome.

The behavior of a poly(aniline) solid contact pH selective electrode based on N,N,N',N'-tetrabenzylethanediamine ionophore

A hydrogen ion-selective solid-contact electrode based on N,N,N',N'-tetrabenzylethanediamine has shown the best Nernstian slope and selectivity and the widest response range in a Tris buffered pH sample solution. Its linear dynamic range was pH 3.50-11.94, and the Nernstian slope showed 52.1 mV/pH (at 20 +/- 0.2 degrees C). When it was directly applied to human whole blood (in pH range 6.0-8.5) we could obtain the same satisfying results. This electrode continuously contacted a Tris 7.47 buffered solution, human whole blood and a hydrofluoric acid solution for one month without any loss of performance. Also, hydrofluoric acid did not influence the surface of this electrode, and thus it was maintained without showing any changes in potentials after being used in a hydrofluoric acid solution. The standard deviation in the determined e.m.f. differences was 1.5 mV (N = 5) for Tris buffer solutions of pH 6.5 and 1.1 mV at a Tris buffer solutions of pH 8.5. The 90% response time of the electrodes obtained by injecting of hydrochloric acid into the Tris buffer sample solution was less than 10 s. Especially, in the this paper, with these potential response characteristics of hydrogen ion selective poly(aniline) solid contact electrode, we have also presented the pH response mechanism of this electrode and the role of poly(aniline) and a doped anion in a poly(aniline) layer.

Metabolic characteristics and prevalence of osteoporosis among women in Tae-An area

Understanding the metabolic changes in women is one of the important ways to prevent and treat osteoporosis. To reveal the metabolic characteristics of 289 healthy women aged between 35-65 yr in Tae-An, Korea we evaluated the association between bone mass assessed by broadband ultrasound attenuation (BUA) using quantitative ultrasound 2 (QUS2) and various parameters such as age, body mass index, serum levels of alkaline phosphatase, calcium, phosphorus, parathyroid hormone, 25(OH)D, and urinary ratios of calcium/creatinine and deoxypyridinoline (Dpyd)/creatinine. Among the subjects, 3.0% were osteoporotic, and 40.9% were osteopenic. When the subjects were classified according to their years since menopause (YSM) and age, the prevalence of osteoporosis increased along with an increase of YSM and age. Bone turnover markers such as serum alkaline phosphatase and fasting urinary Dpyd/creatinine were significantly higher in the group with low bone mass than in the normal group. In summary, this study shows, by use of biochemical markers of bone turnover and QUS2, the prevalence of osteoporosis in women aged between 35-65 in Tae-An was 3.0% and the risk of low bone mass increased with the bone turnover markers.

Flow cytometric evaluation on the age-dependent changes of testicular DNA contents in rats

An age-dependent cellular change of DNA contents in the testis of Sprague-Dawley rats was investigated by flow-cytometric method. Testicular cell suspensions at the age of 4, 5, 6, 7, 8, 10, 12, 16 and 26 weeks were prepared and stained with propidium iodide. The relative proportions in the number of mature and immature haploid (1n), diploid (2n), S-phase and tetraploid (4n) cells were calculated. The proportion in the number of mature haploid cells was sharply increased to the age of 10 weeks (about 38%), thereafter increased slightly to the level of 42% at the age of 26 weeks. The proportion of immature haploid cells was dramatically increased to the age of 6 weeks, then maintained at the level of 20 to 30% thereafter. The proportion of diploid cells was 64% at the age of 4 weeks, then decreased gradually through the age of 26 weeks. The proportion of S-phase cells was increased to the age of 4 weeks, then maintained at a plateau level to the age of 26 weeks. The proportion of tetraploid cells were about 26% at the age of 4 weeks, then decreased gradually to the age of 26 weeks. These results suggest that the proportions of testicular cells may depend on the age of the rat and that the flow cytometric method may be useful in the evaluation of the spermatogenic status with regard to accuracy and sensitivity.

Multi-facet expressions of adenylate cyclase isoforms in B16-F10 melanoma cells differentiated by forskolin treatment

The terminal differentiation of malignant melanoma cells is known to be induced by activating cAMP signaling pathway with alpha-MSH or cAMP analogues. However, sustained activation of cAMP signaling system that induces the differentiation of melanoma cells, also induces the desensitization of the pathway at the receptor level. Nevertheless, the adaptation of adenylate cyclase (AC) expression by sustained activation of cAMP signaling system has not been clearly understood. This study was performed to examine whether the sustained activation of cAMP system induce changes in the expression AC isoforms as an adaptation mechanism. Treatment of B16/F10 murine melanoma cells with 100 mM forskolin for 6 days resulted in differentiation, melanin accumulation and increased expression of tyrosine hydroxylase mRNA. In the forskolin-treated melanoma cells, change in expression of various AC isoform at the transcription level was detected by reverse-transcription polymerase chain reaction (RT-PCR). Expression of AC isoform mRNA: ACI, III, VI, VII, and IX increased to the level of 196-392% of the control whereas the level of ACII was decreased by 30%. The cAMP concentration was increased both in basal and alpha-MSH stimulated cells, but the AC activity was decreased in the forskolin treated cells. Thus, these results suggest that sustained activation of cAMP system induces differential expression of AC isoforms, which results in increase of cAMP accumulation.

Right thoracotomy for mitral reoperation: analysis of technique and outcome

BACKGROUND

This report describes technical details of the right thoracotomy approach for mitral surgery, and analyzes our experience with this procedure for patients with a prior sternotomy. Three methods for myocardial management (hypothermic cardioplegic arrest, beating heart, and fibrillating heart) are compared.

METHODS

Records were abstracted of patients who had a right thoracotomy between January 1, 1992 and July 1, 1999 for mitral surgery after at least one prior sternotomy. Demographic, operative, and outcome data were collected for analysis. Telephone follow-up was used to measure postoperative New York Heart Association functional status.

RESULTS

Eighty-four patients (mean age 60 +/- 15 years) had reoperative mitral surgery via a right thoracotomy. Myocardial management included ventricular fibrillation in 10 patients, operation on the beating heart in 58 patients, and hypothermic blood cardioplegia arrest in 16 patients. The mean time in the operating room was 185 +/- 73 minutes, and the mean duration of cardiopulmonary bypass was 63 +/- 56 minutes. There were no perioperative strokes and the prevalence of death for patients who received cardioplegic arrest was significantly higher than the prevalence of death for patients who had mitral surgery with perfused fibrillating or beating heart techniques (p = 0.007; Fisher's exact test comparing risk-unadjusted mortality).

CONCLUSIONS

Right thoracotomy provides efficient exposure for reoperative mitral surgery. Mitral valve procedures on the fibrillating or beating heart are feasible in most patients and are at least as safe as surgery using cardioplegic arrest.

Differential changes in the expression of cyclic nucleotide phosphodiesterase isoforms in rat brains by chronic treatment with electroconvulsive shock

Electroconvulsive shock (ECS) has been suggested to affect cAMP signaling pathways to exert therapeutic effects. ECS was recently reported to increase the expression of PDE4 isoforms in rat brain, however, these studies were limited to PDE4 family in the cerebral cortex and hippocampus. Thus, for comprehensive understanding of how ECS regulates PDE activity, the present study was performed to determine whether chronic ECS treatment induces differential changes in the expression of all the PDE isoforms in rat brains. We analyzed the mRNA expression of PDE isoforms in the rat hippocampus and striatum using reverse transcription polymerase chain reaction. We found chronic ECS treatment induced differential changes in the expression of PDE isoform 1, 2, 3, 4, 5 and 7 at the rat hippocampus and striatum. In the hippocampus, the expression of PDE1A/B (694%), PDE4A (158%), PDE4B (323 %), and PDE4D (181%) isoforms was increased from the controls, but the expression of PDE2 (62.8%) and PDE7 (37.8%) decreased by chronic ECS treatment. In the striatum, the expression of PDE1A/B (179%), PDE4A (223%), PDE4B (171%), and PDE4D (327%) was increased by chronic ECS treatment with the concomitant decrease in the expression of PDE2 (78.4%) and PDE3A (67.1%). In conclusion, chronic ECS treatment induces differential changes in the expression of most PDE isoforms including PDE1, PDE2, PDE3, PDE4, PDE5, and PDE7 in the rat hippocampus and striatum in an isoform- and brain region-specific manner. Such differential change is suggested to play an important role in regulation of the activity of PDE and cAMP system by ECS.

Mice deficient in Six5 develop cataracts: implications for myotonic dystrophy

Expansion of a CTG trinucleotide repeat in the 3' UTR of the gene DMPK at the DM1 locus on chromosome 19 causes myotonic dystrophy, a dominantly inherited disease characterized by skeletal muscle dystrophy and myotonia, cataracts and cardiac conduction defects. Targeted deletion of Dm15, the mouse orthologue of human DMPK, produced mice with a mild myopathy and cardiac conduction abnormalities, but without other features of myotonic dystrophy, such as myotonia and cataracts. We, and others, have demonstrated that repeat expansion decreases expression of the adjacent gene SIX5 (refs 7,8), which encodes a homeodomain transcription factor. To determine whether SIX5 deficiency contributes to the myotonic dystrophy phenotype, we disrupted mouse Six5 by replacing the first exon with a beta-galactosidase reporter. Six5-mutant mice showed reporter expression in multiple tissues, including the developing lens. Homozygous mutant mice had no apparent abnormalities of skeletal muscle function, but developed lenticular opacities at a higher rate than controls. Our results suggest that SIX5 deficiency contributes to the cataract phenotype in myotonic dystrophy, and that myotonic dystrophy represents a multigenic disorder.

Ligation of ICAM-1 molecules inhibits target cell-induced granule exocytosis of IL-12-activated natural killer cells

The importance of cell adhesion molecules such as ICAM-1 is emphasized in cell-to-cell interactions that are critical in the generation of effective immune reactions. In this study, the involvement of ICAM-1 in natural killer (NK) cell activities was characterized in IL-12-activated human NK cells. To address the question of whether ligation of ICAM-1 molecules can modulate NK cell cytolytic activities, a 4-h (51)Cr-release assay was performed after pretreatment of NK cells with R6.5 mAb (anti-human ICAM-1 mAb). Ligation of membrane ICAM-1 molecules significantly inhibited IL-12-enhanced NK cytotoxicity against K562, and the pretreatment of neutralizing soluble ICAM-1 with R6.5 mAb blocked this inhibitory effect. The involvement of Ca(2+)-dependent granular exocytosis was evaluated. BLT esterase assay demonstrated that the ligation of ICAM-1 molecules inhibited granular exocytosis of NK cells. Additionally, the ICAM-1-mediated inhibition of Ca(2+) flux in NK cells was detected using Fluo-3AM, while the pretreatment of NK cells with R6.5 mAb did not affect conjugate formation between NK and K562 cells. Collectively, these results suggest that the signals transduced from ICAM-1 molecules might be sufficient to induce inhibitory effects on NK cells.

Tylopeptins A and B, new antibiotic peptides from Tylopilus neofelleus

Two new peptides, tylopeptins A and B, were isolated from the methanol extract of the fruiting body of the mushroom, Tylopilus neofelleus. These peptides were identified as peptaibols possessing an acetylated N-terminal residue, fourteen amino acids, and leucinol as the C-terminal amino alcohol. Sequential determination and complete 1H and 13C resonance assignments were based on positive ion FAB mass spectroscopy and two dimensional NMR techniques. These peptides were subsequently shown to be active against some gram-positive bacteria, but inactive against pathogenic fungi and gram-negative bacteria.

Determination of melatonin in biological samples by capillary electrophoresis

The determination of melatonin (MLT) in physiological samples was investigated using capillary electrophoresis (CE). Mouse blood was collected in tubes containing EDTA, centrifuged at 1500 g for 20 min at 4 degrees C, and stored at -20 degrees C. Plasma samples were extracted with dichloroethane, centrifuged and the aqueous phase was discarded. Then the organic phase was evaporated to dryness. The residue was dissolved in deionized water and filtered with a microfilter (0.22 micron). Separations were carried out using a CE system equipped with a fused silica capillary [80 cm (effective length 52 cm) x 75 microns I.D.] and an ultraviolet-visible detector (200 nm), and programmed to provide 25 mM 2-(N-morpholino)ethanesulfonic acid (pH 5.7). Injection was performed hydrostatically by elevating the sample by 10 cm at the cathodic side of the capillary. The calibration curve, reproducibility, recovery and limit of detection were examined, and validation of the method was performed. The result showed that MLT in blood could be easily determined with the new method.

The application of ion chromatographic method for bioavailability and stability test of iron preparations

Postabsorptive serum iron level was determined after oral administration of the compounds to human. In serum and whole blood, Fe3+ was measured by ion chromatography (IC) using a pyridine-2,6-dicarboxylic acid (PDCA) as an eluent. The serum sample solutions were pretreated with I N HCI and 50% TCA. The whole blood sample solutions were treated with 3 N HCI for 30 min at 125 degrees C. The limit of detection (LOD) of the IC technique is 0.2 microM for Fe2- and 0.1 microM for Fe3+. The area under concentration (AUC) can be obtained by the above analytical condition. In addition, to compare the stability of Fe2+ to that of Fe3+ in pharmaceutical preparations, accelerated stability test was carried out. After storing the samples under 40 degrees C, 75%RH in light-resistant container for various time intervals, the contents of iron of different valencies were determined separately by the IC technique and the change and/or the interchange of among those iron species in preparations was investigated. Iron raw materials are stable, but Fe2+ in Fe3+ source materials was slightly converted to Fe3+ by oxidation. Fe2+ in Fe3+ source raw materials and Fe3+ in Fe2+ raw materials are determined as impurities. Therefore, IC technique is found to be an appropriate method for comparative evaluation of dissimilar bioavailability of Fe2+ and Fe3+, stability of Fe2+ and Fe3+ raw materials and preparations.

Polarized expression and function of the costimulatory molecule CD58 on human intestinal epithelial cells

BACKGROUND & AIMS

Intestinal epithelial cells (IECs) can process foreign protein antigens and display antigenic peptides to CD4(+) T lymphocytes via HLA class II molecules. The purpose of this study was to determine the nature of the second, or costimulatory, signal provided by IECs.

METHODS

We investigated surface expression of the costimulatory molecules CD58 (LFA-3), CD80 (B7-1), and CD86 (B7-2) by using flow cytometry, confocal microscopy, and vectorial biotinylation. Antibodies specific for CD58, CD80, and CD86 were used in blocking experiments to assess the role of these molecules in providing a costimulatory signal to CD4(+) T cells by IECs.

RESULTS

CD58, but not CD80 or CD86, was observed to be expressed constitutively on both native IECs and in the IEC lines T84 and HT-29. The surface expression of CD58 was highly polarized and restricted to the basolateral surface of the cell. Antibodies against CD58, but not CD80 or CD86, inhibited the stimulation of CD4(+) T-cell proliferation mediated by IECs.

CONCLUSIONS

CD58 is expressed by polarized IECs in a topologically restricted manner at the region of T-cell contact and can function as a costimulatory molecule in HLA class II-mediated antigen presentation.

Phototoxicity of melatonin

Melatonin (MLT), N-acetyl-5-methoxytryptamine, is mainly secreted by the pineal gland. The ultraviolet (UV), infrared (IR) and 1H-NMR spectra of irradiated and non-irradiated MLT were measured, and phototoxicity tests of MLT, anthracene (positive control) and sodium lauryl sulfate (SLS, negative control) were performed. The methods employed include both in vitro tests such as MTS assay using the human fibroblast cell and yeast growth inhibition assay using Candida albicans and in vivo method using the skin of guinea pig. UV absorption spectra and 1H-NMR spectra of MLT were changed by UVA (365 nm, 15 J/cm2), but IR spectra of MLT were not changed. The fifty percent inhibitor concentration (IC50) ratio (UV-/UV+) of MLT was 10. The inhibition zone of irradiated-paper disks treated with MLT was not observed. According to the results of histopathological examination, no pathologic lesion was observed in the non-irradiated group, but slight degeneration of keratinocytes in the epidermis, hemorrhage and vasodilation in dermis were observed in the irradiated group. These results indicate that the molecular structure of MLT is altered by UVA to unidentified photoproducts and a moderate phototoxicity of MLT is predicted.

Antitumor effects of IL-6 on murine liver tumor cells in vivo

IL-6 is a pleiotropic cytokine that is capable of modulating the diverse functions of hepatocytes such as acute phase responses and inflammation in the liver. To learn its antitumor effects in vivo, the cDNA of IL-6 was transfected into murine liver cells, TIB cells. IL-6-transfected TIB cells (TIB73-IL-6 or TIB75-IL-6) produced much higher levels of IL-6 compared with vector-transfected TIB cells (TIB73-vec or TIB75-vec). To investigate the effects of IL-6 on TIB tumor growth in vivo, IL-6-transfected TIB cells or vector-transfected TIB cells were injected subcutaneously into syngeneic mice. Vector-transfected TIB cells grew rapidly 3 weeks after injection, but IL-6-transfected TIB cells did not grow at all for up to 6 weeks. Pathologically, IL-6-transfected TIB cells demonstrated a severe necrosis and apoptotic pattern. Taken together, these results indicate that IL-6 functions as a growth inhibiting factor in vivo, and another biological role of IL-6 in the liver is suggested.

Highly polarized HLA class II antigen processing and presentation by human intestinal epithelial cells

The high concentration of foreign antigen in the lumen of the gastrointestinal tract is separated from the underlying lymphocytes by a single cell layer of polarized epithelium. Intestinal epithelial cells can express HLA class II antigens and may function as antigen-presenting cells to CD4(+) T cells within the intestinal mucosa. Using tetanus toxoid specific and HLA-DR-restricted T lymphocytes, we show that polarized intestinal epithelial cells directed to express HLA-DR molecules are able to initiate class II processing only after internalization of antigen from their apical surface. Coexpression of the class II transactivator CIITA in these cells, which stimulates highly efficient class II processing without the characteristic decline in barrier function seen in polarized monolayers treated with the proinflammatory cytokine gamma-IFN, facilitates antigen processing from the basolateral surface. In both cases, peptide presentation to T cells via class II molecules was restricted to the basolateral surface. These data indicate a highly polarized functional architecture for antigen processing and presentation by intestinal epithelial cells, and suggest that the functional outcome of antigen processing by the intestinal epithelium is both dependent on the cellular surface at which the foreign antigen is internalized and by the underlying degree of mucosal inflammation.

Inhibition by ginsenosides Rb1 and Rg1 of methamphetamine-induced hyperactivity, conditioned place preference and postsynaptic dopamine receptor supersensitivity in mice

The ginsenosides Rb1 and Rg1, the major components of ginseng saponin, inhibited not only methamphetamine-induced hyperactivity but also conditioned place preference (CPP) in mice following a single or repeated administration. Dopamine (DA) receptor supersensitivity, which developed in methamphetamine-induced CPP mice, was also inhibited by both Rb1 and Rg1. Therefore, the present results suggest that Rb1 and Rg1 may be the active components of ginseng saponin in the modulation of methamphetamine-induced dopaminergic behaviors such as hyperactivity and CPP, supporting our previous conclusion that ginseng saponin might modulate methamphetamine-induced dysfunction at both the pre- and postsynaptic DA receptors.

Modulation of NK-target cell interaction by a monoclonal antibody to K562 cells

In order to identify the target cell recognition molecules involved in the interaction between natural killer (NK) cells and target cells, we have generated monoclonal antibodies to K562, NK-sensitive target cells. After screening by FACScan for the reactivity to K562, one monoclonal antibody (mAb), 4A60, was selected. MAb 4A60 was found to inhibit the proliferation of NK cells induced by IL-2 and K562 cells. However, this monoclonal antibody could not significantly block the conjugate formation between NK and target cells. Moreover, mAb 4A60 only slightly inhibited the cytotoxicity of NK cells induced by IL-2. Protein analysis showed that mAb 4A60 recognized a 53-kDa protein of K562 cells. Taken together, these data suggest that mAb 4A60 inhibits the proliferation of NK cells induced by IL-2 and target cells, and the 53-kDa protein, a tentative ligand of this mAb of K562, may be involved in this process.

Intestinal epithelial cells use two distinct pathways for HLA class II antigen processing

Intestinal epithelial cells express a low level of HLA class II molecules constitutively, with elevated levels seen in the setting of mucosal inflammation including inflammatory bowel disease. The ability of intestinal epithelial cells to act as antigen presenting cells for alphabeta CD4(+) T lymphocytes was examined through a molecular analysis of the HLA class II antigen processing pathway. We have shown that intestinal epithelial cells contain abundant constitutive levels of the cathepsin proteases proven to function in HLA class II mediated antigen presentation. Activation of these cells by gamma-IFN induced the expression of invariant chain and HLA-DM alphabeta, thus facilitating the formation of compact, SDS-stable HLA- DR alphabeta heterodimers. Using HLA-DR-restricted T cells and retroviral mediated gene transfer of HLA-DR alleles into the intestinal epithelial cell lines HT-29 and T84, we demonstrated efficient antigen processing and presentation to CD4(+) T lymphocytes in the presence of the proinflammatory cytokine gamma-IFN. The class II processing pathway and presentation in the presence of gamma-IFN was indistinguishable from that observed with a conventional antigen presenting cell. Antigen processing also occurred in intestinal epithelial cells in the absence of gamma-IFN, and in contrast to that seen after stimulation with gamma-IFN, required high concentration of antigen and was not inhibited by the protease inhibitor leupeptin. These data suggest the use of two distinct pathways of HLA class II antigen processing in enterocytes with differential immunomodulatory properties in the presence or absence of mucosal inflammation.

Blockade by naloxone of cocaine-induced hyperactivity, reverse tolerance and conditioned place preference in mice

Cocaine-induced hyperactivity was inhibited by a single administration of naloxone (2 and 5 mg/kg, i.p.), an opioid receptor antagonist, and naloxone administered prior to and during the chronic injection of cocaine attenuated the development of both cocaine-induced reverse tolerance and conditioned place preference (CPP). Dopamine (DA) receptor supersensitivity which developed in cocaine-induced reverse tolerant or CPP mice, was also inhibited by naloxone. Furthermore, naloxone reduced an apomorphine-induced striatal dopaminergic action, climbing behavior. Therefore, the present studies suggest that cocaine-induced dopaminergic behaviors, such as hyperactivity, reverse tolerance and CPP, may be commonly produced via activation of an opioid receptor. The development of DA receptor supersensitivity may be a possible common mechanism of cocaine-induced reverse tolerance and CPP, since cocaine-induced changes in sensitivity to apomorphine, as well as apomorphine-induced climbing behavior in mice, were both inhibited by naloxone.

Blockade by ginseng total saponin of methamphetamine-induced hyperactivity and conditioned place preference in mice

Ginseng total saponin (GTS) inhibited methamphetamine-induced hyperactivity and conditioned place preference (CPP). Dopamine (DA) receptor supersensitivity was developed in methamphetamine-induced CPP mice and it was inhibited by GTS. GTS also inhibited apomorphine-induced climbing behavior, showing the antidopaminergic activity of GTS. These results suggest that GTS inhibition of the methamphetamine-induced hyperactivity and CPP may be closely related with the inhibition of dopaminergic activation induced by methamphetamine.

Behavioral changes with alterations of choline acetyltransferase immunoreactivities induced by N-butyl benzenesulfonamide

N-butyl benzenesulfonamide (NBBS), one of the sulfonamide plasticizers, induced characteristic effects to Wistar rats after acute repeated exposures (300 mg/kg body weight, ip every 6 h). The signs were pica, staggering gait with hindlimb-paresis and splaying, teeth-grinding, self paw-biting and coma. The motor activity parameters showed generalized decreased mobility. The gait and hindlimb abnormalities coexisted with changes of lower motoneuron activity, ie decreased immunoreactivity of choline acetyltransferase in the lumbar spinal cord. The effects became more overt with repeated exposure to NBBS and the severity was increased. These effects were short-lived and the animals soon recovered.

Blockade by ginseng total saponin of the development of methamphetamine reverse tolerance and dopamine receptor supersensitivity in mice

Repeated administration of methamphetamine (2 mg/kg) developed reverse tolerance to the ambulation-accelerating effect. Intraperitoneal administration of ginseng total saponin (GTS, 200 mg/kg of body weight) prior to and during chronic administration of methamphetamine inhibited the development of reverse tolerance. Dopamine receptor supersensitivity was also developed in reverse tolerant mice which had received the same methamphetamine. The development of dopamine receptor supersensitivity was evidenced by the enhanced hypothermic response to apomorphine (1 mg/kg) and the enhanced ambulatory activity of apomorphine (4 mg/kg). GTS also prevented the development of dopamine receptor supersensitivity induced by the chronic administration of methamphetamine. These results show that GTS may be useful for the prevention of and therapy for the adverse action of methamphetamine. It is concluded that the development of reverse tolerance to methamphetamine may be associated with the enhanced dopamine receptor supersensitivity since both phenomena were blocked by GTS.

Antimicrobial susceptibility of Campylobacter fetus subsp. fetus isolated from blood and synovial fluid

Campylobacter fetus subsp. fetus is a rare human pathogen, but can cause serious extraintestinal infections. Effective antimicrobial agent is required for the therapy, but we have very limited knowledge on the susceptibility of the organism. In this study, the susceptibility of 25 isolates of the organism to 14 antimicrobial agents was tested by an agar dilution method. Antimicrobial agents with low MIC ranges, in micrograms/ml, were: meropenem < or = 0.25, dirithromycin < or = 0.5, gentamicin < or = 1, amikacin, ofloxacin, tetracycline and erythromycin < or = 2. The MIC range of cefepime was 0.5-8 micrograms/ml, but those of other beta-lactams were relatively high. All of the isolates were interpreted to be susceptible to cefepime, meropenem, amikacin, gentamicin, ofloxacin, tetracycline and dirithromycin. A significant proportion of the isolates were either intermediate or resistant to ampicillin, cephalothin, cefotaxime, aztreonam, loracarbef and erythromycin. In conclusion, the organism remains susceptible to aminoglycosides and tetracycline. Greater in vitro activity of meropenem, ofloxacin and dirithromycin require clinical evaluation.

An alternative approach to myelodysplasia management: aggressive observation and prompt intervention

We have adopted an approach to the management of myelodysplasia patients which is contrary to that most commonly supported by the existing literature. We screen patients shortly after birth with ultrasound, urine culture and serum creatinine, and then follow patients at 3 to 6-month intervals with similar studies. Cystography and urodynamics are done only as required clinically or by a change in the sonogram. Clean intermittent catheterization is indicated for continence or medical reasons. With this approach of aggressive observation and prompt intervention, we observed a rate of renal deterioration (diminished function on renal scan or parenchymal loss on imaging studies) of 5%. Renal deterioration was associated statistically with urinary tract infections and reflux. Patients started on clean intermittent catheterization for medical indications had greater risk for renal deterioration than those started on it for continence. Renal deterioration occurred with equal frequency between patients with abnormal and normal urodynamic studies, that is urodynamics did not predict renal deterioration. Our data show a rate of renal deterioration similar to other reports. We believe that aggressive observation with prompt intervention for problems once identified represents a reasonable alternative to managing patients with myelodysplasia.

Effects of hormone replacement therapy on lipoprotein(a) and lipids in postmenopausal women

High concentrations of lipoprotein(a) [Lp(a)], an independent risk factor for atherosclerosis, cannot be managed by the usual lipid-lowering agents. It has been suggested that Lp(a) levels are related to female sex hormones. Estrogen replacement therapy makes the lipid profiles favorable for delaying atherosclerosis in postmenopausal women. The effects of the combination therapy of estrogen and progesterone on lipids are controversial. This study was designed to evaluate the effect of female sex hormones on the concentration of Lp(a) and to clarify the influence of progesterone on the effect of estrogen in postmenopausal women. Postmenopausal women (n = 184) were divided into four groups: control; 0.625 mg conjugated equine estrogen (CEE) plus 10 mg medroxyprogesterone acetate (MPA); 0.625 mg CEE plus 5 mg MPA; and 0.625 mg CEE only. Medication for 2 months lowered the concentrations of Lp(a) by 20% in all treated groups. The decrease was more pronounced in subjects with a relatively higher basal Lp(a) concentration. Estrogen replacement therapy raised the concentration of high-density lipoprotein cholesterol and decreased low-density lipoprotein cholesterol without changing total cholesterol. The combination therapy of estrogen and progesterone abolished the effect of estrogen on high-density lipoprotein cholesterol. Hormone replacement therapy lowered Lp(a) levels in postmenopausal women. The effect was prominent in subjects with high basal Lp(a) levels. This decrease may be one of the mechanisms of the cardioprotective effects of estrogen. The cardioprotective effect of estrogen cannot be applied to the combination therapy due to the adverse effect of progesterone on high-density lipoprotein cholesterol.

Organotropic formation and disappearance of 8-hydroxydeoxyguanosine in the kidney of Sprague-Dawley rats exposed to adriamycin and KBrO3

A form of oxidative DNA damage, 8-hydroxydeoxyguanosine (8-OHdG), was comparatively determined for 48 h in the kidney and liver isolated from Sprague-Dawley rats i.p. treated with Adriamycin; potassium bromate (KBrO3), hydroquinone and vitamin A. HPLC-ECD analysis system showed that Adriamycin and KBrO3, renal carcinogens, induced higher levels of 8-OHdG in the target organ of kidney (12-13.8 residues/10(4) dG(deoxyguanosine)) compared to those in the liver (3.4-3.8 residues/10(4) dG) and showed highly persistent levels (8 residues, 10(4) dG) in the kidney. The data suggest that the organotropic persistence of 8-OHdG may provide a useful marker for identifying target organ systems in oxidative chemical carcinogenesis and screening free radical-generating carcinogens.