Association of Serum Biomarkers With Pulmonary Involvement of Rheumatoid Arthritis Interstitial Lung Disease: From KORAIL Cohort Baseline Data

Objective

The increase in mortality in rheumatoid arthritis (RA) patients with interstitial lung disease (ILD) is well known However, there are few studies on serum markers that can evaluate acute exacerbation or prognosis in RA-ILD patients The purpose of this study was to identify the association between biomarkers and lung lesions in patients with RA-ILD.

Methods

We analyzed 153 patients with serum samples in a prospective, multicenter cohort of Korean RA-ILD patients The serum levels of biomarkers, matrix metalloproteinase (MMP-7), surfactant protein-D (SP-D), and Krebs von den Lungen-6 (KL-6) were measured and correlated with forced vital capacity (FVC), diffusing capacity for carbon monoxide (DLCO) and the results of computed tomography (CT) CT results were interpreted semi-quantitatively according to the extent of lung lesions (grade 1, 0%∼25%; grade 2, 26%∼50%; grade 3, 51%∼75%; grade 4, 76%∼100%).

Results

MMP-7, SP-D, and KL-6 were negatively correlated with FVC (MMP-7, r=-0267, p=0001; SP-D, r=-0250, p=0002; KL-6, r=-0223, p=0006) and DLCO (MMP-7, r=-0404, p<0001; SP-D, r=-0286, p=0001; KL-6, r=-0226, p=0007) In addition, MMP-7, SP-D, and KL-6 tended to increase with higher grades of lung lesions on CT (MMP-7, p=0013; SP-D, p<0001; KL-6, p<0001).

Conclusion

MMP-7, SP-D, and KL-6 can be used to evaluate the functional and anatomical status of lung involvement in the RA-ILD patients.

Comparison of the 2017 EULAR/ACR Criteria with Clinicoserologic Criteria for the Classification of Idiopathic Inflammatory Myopathies in Korean Patients

PURPOSE

To investigate correlations between myositis-specific autoantibodies (MSA) or myositis-associated antibodies (MAA) and clinical features, thereby demonstrating the utility of clinicoserologic classification in idiopathic inflammatory myopathies (IIM) patients.

MATERIALS AND METHODS

We conducted a multicenter study of 108 adult patients (age ≥18 years) who were diagnosed with IIM by Peter and Bohan criteria or 2004 European Neuromuscular Centre (ENMC) criteria. Clinical data were obtained by medical record review. Immunoblot assay with Euroline strip (EUROIMMUN, Germany) was performed using the sera of dermatomyositis (DM, n=56), polymyositis (PM, n=45), amyopathic DM (n=5), DM sine dermatitis (n=1), and immune mediated necrotizing myopathy (n=1) patients. Patients were classified based on two classifications: 2017 EULAR/ACR and novel clinicoserologic classification.

RESULTS

According to 2017 EULAR/ACR criteria, DM and PM were the most and the second most frequent entities. Overlap myositis was the major entity of IIM, and the frequency of PM was significantly lower when applying clinicoserologic classification criteria. Sixty-nine (63.9%) patients had one or more MSA, and 61 (56.5%) patients had one or more MAA. Interstitial lung disease was closely associated with anti-MDA5 and anti-ARS, and DM-specific skin lesions were frequently observed in patients with anti-TIF1γ, anti-SRP, and anti-MDA5.

CONCLUSION

The clinicoserologic criteria based on MSA/MAA positivity could reflect more precise clinical features of IIM. Establishment of a laboratory system routinely available to screen for MSA/MAA status will be beneficial to provide precise diagnosis and proper management of IIM patients.

Predicting Imaging Remission in Rheumatoid Arthritis: a Case-control Ultrasound Study

BACKGROUND

To elucidate the achievement rates of imaging remission and to examine the characteristics associated with imaging remission status among patients with rheumatoid arthritis (RA) who have attained clinical remission.

METHODS

Ninety-seven patients with RA patients who had attained clinical remission, defined by DAS28-ESR < 2.6 were enrolled. Power Doppler ultrasonography (PDUS) was performed on 16 joints and 2 tendons, including the first to third metacarpophalangeal, second and third proximal interphalangeal, radiocarpal (RC), second and third metatarsophalangeal joints, and extensor carpi ulnaris tendons. They were graded based on a dichotomous assessment. The clinical and laboratory data of patients who had attained imaging remission were compared to those of patients who had attained only clinical remission.

RESULTS

The imaging remission rate was 51.5% in patients who had attained clinical remission. Forty-seven patients (48.5%) were PDUS positive. Power Doppler was detected most frequently in the right RC joint (n = 40). PDUS positive patients had higher evaluator global assessment (EGA) scores (P < 0.001) than PDUS negative patients. PDUS positive patients also had higher clinical disease activity index and simplified clinical disease activity index scores than PDUS negative patients. Patients who had attained imaging remission had lower pain scores and used nonsteroidal anti-inflammatory drugs less frequently. Patients who had attained imaging remission had higher rheumatoid factor (RF) and anti-cyclic citrullinated peptide levels. A low EGA score was found to be a predictor of imaging remission achievement among patients who had attained clinical remission.

CONCLUSION

Only 51.5% of the patients with RA who had attained clinical remission were also in imaging remission. Patients who had attained imaging remission had lower EGA scores and higher RF levels than patients who had attained only clinical remission.

Seasonal Variations and Associated Factors of Gout Attacks: a Prospective Multicenter Study in Korea

BACKGROUND

We purposed to evaluate the seasonality and associated factors of the incidence of gout attacks in Korea.

METHODS

We prospectively enrolled patients with gout attacks who were treated at nine rheumatology clinics between January 2015 and July 2018 and followed them for 1-year. Demographic data, clinical and laboratory features, and meteorological data including seasonality were collected.

RESULTS

Two hundred-five patients (men, 94.1%) were enrolled. The proportion of patients with initial gout attacks was 46.8% (n = 96). The median age, body mass index, attack duration, and serum uric acid level at enrollment were 50.0 years, 25.4, 5.0 days, and 7.4 mg/dL, respectively. Gout attacks were most common during spring (43.4%, P < 0.001) and in March (23.4%, P < 0.001). A similar pattern of seasonality was observed in the group with initial gout attacks. Alcohol was the most common provoking factor (39.0%), particularly during summer (50.0%). The median diurnal temperature change on the day of the attack was highest in the spring (9.8°C), followed by winter (9.3°C), fall (8.6°C), and summer (7.1°C) (P = 0.027). The median change in humidity between the 2 consecutive days (the day before and the day of the attack) was significantly different among the seasons (3.0%, spring; 0.3%, summer; -0.9%, fall; -1.2%, winter; P = 0.015). One hundred twenty-five (61%) patients completed 1-year follow-up (51% in the initial attack group). During the follow-up period, 64 gout flares developed (21 in the initial attack group). No significant seasonal variation in the follow-up flares was found.

CONCLUSION

In this prospective study, the most common season and month of gout attacks in Korea are spring and March, respectively. Alcohol is the most common provoking factor, particularly during summer. Diurnal temperature changes on the day of the attack and humidity changes from the day before the attack to the day of the attack are associated with gout attack in our cohort.

Hypocomplementemic Urticarial Vasculitis Syndrome with Membranous Nephropathy: Case Report

Urticarial vasculitis is a rare disorder that principally manifests with recurrent urticarial, sometimes hemorrhagic, skin lesions and/or angioedema. Its clinical presentation is not always limited to cutaneous lesions and it can potentially affect other organs, such as the joints, lungs, kidneys, and eyes. Systemic involvement can either be present at the onset of disease or develop over time. In cases with systemic manifestations, urticarial vasculitis is more likely to be associated with a low complement level. We present the case of a teenage boy with hypocomplementemic urticarial vasculitis syndrome (HUVS) that occurred shortly following swine-origin influenza A virus infection in 2009. Afterwards, HUVS was systemically complicated with myositis and membranous nephropathy that developed several months and about 2 years after its onset, respectively. A combination of glucocorticoid and immunosuppressive agents has been used to effectively control disease activity.

Factors Contributing to Discordance between the 2011 ACR/EULAR Criteria and Physician Clinical Judgment for the Identification of Remission in Patients with Rheumatoid Arthritis

Remission is a primary end point of in clinical practice and trials of treatments for rheumatoid arthritis (RA). The 2011 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) remission criteria were developed to provide a consensus definition of remission. This study aimed to assess the concordance between the new remission criteria and the physician's clinical judgment of remission and also to identify factors that affect the discordance between these two approaches. A total of 3,209 patients with RA were included from the KORean Observational Study Network for Arthritis (KORONA) database. The frequency of remission was evaluated based on each approach. The agreement between the results was estimated by Cohen's kappa (κ). Patients with remission according to the 2011 ACR/EULAR criteria (i.e. the Boolean criteria) and/or physician judgment (n = 855) were divided into three groups: concordant remission, the Boolean criteria only, and physician judgment only. Multinomial logistic regression analysis was used to identify factors responsible for the assignment of patients with remission to one of the discordant groups rather than the concordant group. The remission rates using the Boolean criteria and physician judgment were 10.5% and 19.9%, respectively. The agreement between two approaches for remission was low (κ = 0.226) and the concordant remission rate was only 5.5% (n = 177). Pain affected classification in both discordant groups, whereas fatigue was associated with remission only by physician clinical judgment. The Boolean criteria were more stringent than clinical judgment. Patient subjective symptoms such as pain and fatigue were associated with discordance between the two approaches.

Association between catechol-O-methyl transferase gene polymorphisms and fibromyalgia in a Korean population: A case-control study

BACKGROUND

Although polymorphisms of the catechol-O-methyl transferase (COMT) gene have been implicated in altered pain sensitivity, results concerning the association between COMT gene polymorphisms and fibromyalgia (FM) are equivocal. We assessed the associations between COMT single-nucleotide polymorphisms (SNP) and FM risk and symptom severity.

METHODS

In total, 409 FM patients and 423 controls were enrolled. Alleles and genotypes at five positions [rs6269 (A>G), rs4633 (C>T), rs4818 (C>G), rs4680 (C>G) and rs165599 (A>G)] in the COMT gene were genotyped from peripheral blood DNA.

RESULTS

Alleles and genotypes of the rs4818 COMT gene polymorphism were significantly associated with increased susceptibility to FM. The rs4818 GG genotype was more strongly associated with FM compared to the CC genotype (OR = 1.680, 95% CI: 1.057, 2.672, p = 0.027). Although allele and genotype frequencies did not differ among groups, the rs4633 CT genotype was not associated with the presence of FM following adjustment for age and sex (OR = 0.745; 95% CI: 0.558, 0.995; p = 0.046). However, no association was observed between clinical measures and individual COMT SNPs. In haplotype analysis, there was a significant association between ACG haplotype and FM susceptibility sex (OR = 2.960, 95% CI: 1.447, 6.056, p = 0.003) and the number of tender points (p = 0.046).

CONCLUSIONS

This large-scale study suggests that polymorphisms of the COMT gene may be associated with FM risk and pain sensitivity in Korean FM patients. However, our results differed to those of previous studies, suggesting ethnic variation in COMT gene polymorphisms in FM.

WHAT DOES THIS STUDY ADD

By contrast to Caucasian and Latin-American populations, the COMT gene polymorphisms are associated with FM risk and pain sensitivity in Korean FM patients, suggesting ethnic variation in COMT gene polymorphisms.

Risk factors for osteoporosis in long-term survivors of intracranial germ cell tumors

SUMMARY

We measured bone mineral densities in 28 intracranial germ cell tumor long-term survivors. There was the high prevalence of osteoporosis and osteopenia, 25.0% and 42.9%, respectively, and three additional risk factors, male sex, a low lean mass, and adult growth hormone replacement, were identified.

INTRODUCTION

Intracranial germ cell tumor long-term survivors (iGCTLS) have many risk factors for osteoporosis, including irradiation from cancer therapy and multiple hormone deficiencies. However, no study of bone mineral density (BMD) has been conducted in iGCTLS because these tumors are rare. The aims of this study were to evaluate the prevalence of osteoporosis and to identify risk factors associated with reduced bone mass in iGCTLS.

METHODS

We evaluated BMD and body composition of 28 iGCTLS (10.9 ± 5.2 years after cancer treatment; 13 males) using dual-energy X-ray absorptiometry. To determine risk factors, we analyzed the medical history, including the nature of the tumor, treatment modality, endocrine status, hormone replacement therapy, lifestyle, and biochemical parameters.

RESULTS

Twenty-five percent of iGCTLS were diagnosed with osteoporosis and 42.9% with osteopenia. Most males (92.3%) had low BMD. Lean mass (LM) was positively correlated with BMD in all regions of interest, and the starting age of adult growth hormone (GH) replacement was negatively correlated with the BMD Z-score at the femur neck. In logistic regression analysis, male sex and low LM were related to low BMD.

CONCLUSIONS

The iGCTLS had a high prevalence of low BMD. We found that male sex, low LM, and delayed start of adult GH replacement were risk factors for osteoporosis. Therefore, the BMD of all iGCTLS should be evaluated, and if it is low, proper management should be started early.

Reactive oxygen species-dependent necroptosis in Jurkat T cells induced by pathogenic free-living Naegleria fowleri

Naegleria fowleri, a free-living amoeba, is the causative pathogen of primary amoebic meningoencephalitis in humans and experimental mice. N. fowleri is capable of destroying tissues and host cells through lytic necrosis. However, the mechanism by which N. fowleri induces host cell death is unknown. Electron microscopy indicated that incubation of Jurkat T cells with N. fowleri trophozoites induced necrotic morphology of the Jurkat T cells. N. fowleri also induced cytoskeletal protein cleavage, extensive poly (ADP-ribose) polymerase hydrolysis and lactate dehydrogenase (LDH) release. Although no activation of caspase-3 was observed in Jurkat T cells co-incubated with amoebae, intracellular reactive oxygen species (ROS) were strongly generated by NADPH oxidase (NOX). Pretreating cells with necroptosis inhibitor necrostatin-1 or NOX inhibitor diphenyleneiodonium chloride (DPI) strongly inhibited amoeba-induced ROS generation and Jurkat cell death, whereas pan-caspase inhibitor z-VAD-fmk did not. N. fowleri-derived secretory products (NfSP) strongly induced intracellular ROS generation and cell death. Necroptotic effects of NfSP were effectively inhibited by pretreating NfSP with proteinase K. Moreover, NfSP-induced LDH release and intracellular ROS accumulation were inhibited by pretreating Jurkat T cells with DPI or necrostatin-1. These results suggest that N. fowleri induces ROS-dependent necroptosis in Jurkat T cells.

Calpain mediates degradation of cytoskeletal proteins during Jurkat T-cell death induced by Entamoeba histolytica

Entamoeba histolytica is known to induce host cell death via activation of calpain and caspases. In this study, we investigated the specific proteases involved in the degradation of cytoskeletal proteins during Jurkat T-cell death induced by E. histolytica. Amoebic trophozoites induced marked degradation of paxillin, Cas, vimentin, vinculin and talin, as well as α- or β-spectrin, in Jurkat T cells. The cleavage effects of E. histolytica were strongly retarded by pretreatment with a calpain inhibitor, but not with a pan-caspase inhibitor. In addition, calpain knockdown with siRNA in Jurkat T cells effectively inhibited E. histolytica-induced PARP, paxillin, α-spectrin, β-spectrin and talin degradation, as compared to scrambled siRNA. These results suggest that calpain plays a crucial role in the cleavage of cytoskeletal proteins during cell death induced by E. histolytica.

Up-regulation of cyclooxygenase-2-derived prostaglandin E(2) in colon cancer cells resistant to 5-fluorouracil

PURPOSE

It has been suggested that constitutive up-regulation of cyclooxygenase (COX)-2 is associated with resistance to apoptosis, increased angiogenesis, and increased tumor invasiveness in various cancers including colon cancer. There are many factors involved in the resistance to 5-fluorouracil (5-FU) in colon cancer. However, little is known about the role of COX-2 in acquired resistance to 5-FU in colon cancer.

METHODS

Hence we investigated whether COX-2 contribute to acquired resistance to 5-FU in colon cancer cells, using cytotoxicity assay for cell survival, reverse transcription-polymerase chain reaction (RT-PCR) for vascular endothelial growth factor (VEGF), quantitative RT-PCR for COX-1 and COX-2, and enzyme-linked immunosorbent assay for PGE(2).

RESULTS

The 5-FU resistant colon cancer cells, SNU-C5/5FUR, showed increased expression of COX-2, prostaglandin E(2) (PGE(2)), and VEGF, compared to its parental cell (SNU-C5). By treatment with meloxicam, the expression of PGE(2) and VEGF was reduced significantly in the resistant cells, but not in the parent cells.

CONCLUSION

These results demonstrate that COX-2 derived PGE(2) is up-regulated and COX-2 inhibitor may have an anti-angiogenic effect in the colon cancer cells resistant to 5-FU.

Calpain-dependent cleavage of SHP-1 and SHP-2 is involved in the dephosphorylation of Jurkat T cells induced by Entamoeba histolytica

Host cell death induced by Entamoeba histolytica is an important mechanism for both host defence and microbial immune evasion during human amoebiasis. However, the signalling pathways underlying cell death induced by E. histolytica are not fully understood. This study investigated the involvement of the protein tyrosine phosphatases (PTPs) SHP-1 and SHP-2 in the dephosphorylation associated with E. histolytica-induced host cell death. Incubation with E. histolytica resulted in a marked decrease in protein tyrosine phosphorylation levels and degradation of SHP-1 or SHP-2 in Jurkat cells. Pre-treatment of cells with a calpain inhibitor, calpeptin, impeded the amoeba-induced dephosporylation and cleavage of SHP-1 or SHP-2. Additionally, inhibition of PTPs with phenylarsine oxide (PAO) attenuated Entamoeba-induced dephosphorylation and DNA fragmentation in Jurkat T cells. These results suggest that calpain-dependent cleavage of SHP-1 and SHP-2 may contribute to protein tyrosine dephosphorylation in Jurkat T cell death induced by E. histolytica.

Mitochondrial respiration is required for activation of ERK1/2 and caspase-3 in human eosinophils stimulated with hydrogen peroxide

BACKGROUND

Eosinophils are important effector cells in the pathogenesis of allergic diseases such as bronchial asthma. Oxidative stress in the form of cellular reactive oxygen species (ROS) has been implicated in the pathogenesis of several allergic diseases. Recently, it has become evident that mitochondrial-derived ROS are important transducers of apoptosis and intracellular signaling. In this study, we investigated the role of mitochondrial ROS in the activation of extracellular signal-regulated kinases (ERK) 1 and 2-mitogen-activated protein kinase (MAPK) and caspase-3 in human eosinophils stimulated with H2O2.

METHODS

Human eosinophils were purified using immunomagnetic negative selection and then stimulated with H2O. H2O2-induced eosinophil apoptosis was measured by staining cells with annexin V. Activation of ERK1/2 MAPK and caspases was assessed by Western blotting. Eosinophils were pretreated with rotenone, an inhibitor of the mitochondrial electron transport chain, before H2O2 was added.

RESULTS

Treatment with 1 mM H2O2 induced externalization of phosphatidylserine (PS) and activation of caspases in eosinophils. H2O2-triggered PS externalization and cleavage of caspase-3 were markedly inhibited by pretreatment with the mitochondrial ROS scavenger N-acetyl-L-cysteine. In addition, H2O2 strongly induced phosphorylation of ERK1/2, but not ERK5, in eosinophils. Hydrogen peroxide-triggered activation of caspase-3 and ERK1/2 was attenuated by pretreatment with rotenone.

CONCLUSIONS

These results suggest that mitochondrial respiration is essential for activation of ERK1/2 and caspase-3 in human eosinophils stimulated with H2O2.

Association of the -2510A/G chemokine (C-C motif) ligand 2 polymorphism with knee osteoarthritis in a Korean population

OBJECTIVE

To investigate the possible association between polymorphisms [the -2510A/G promoter polymorphism (rs1024611) and the Cys35Cys coding polymorphism (rs4586) in exon 2] of the chemokine (C-C motif) ligand 2 (CCL2) gene and knee osteoarthritis (OA) in a Korean population.

METHODS

DNA was obtained from 153 Korean primary knee OA patients and 270 healthy controls. CCL2 genomic variants (-2510A/G and Cys35Cys polymorphisms) were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In additional, the effect of -2510A/G on CCL2 transcription was examined, using a luciferase reporter gene construct transfected into HMC-1 cells.

RESULTS

The -2510A/G promoter polymorphism was associated with OA [genotype frequency, p = 0.041; allele frequency, p = 0.017, odds ratio (OR) = 1.45, 95% confidence interval (CI) = 1.07-1.96]. Significant association was observed between the G carrier of the -2510A/G promoter polymorphism and primary knee OA patients (p = 0.021, OR = 2.25, 95% CI = 1.12-4.52). The G carrier of the -2510A/G promoter polymorphism was also associated with both clinically subtyped OA patients (OA patients with functionally poor index and radiographically severe OA patients). However, no significant difference was found in the Cys35Cys polymorphism. Haplotype frequency analysis revealed a significant difference (chi(2) = 8.98, p = 0.030). The CCL2 serum level of subjects with the G carrier (290.0+/-87.5 pg/mL) of the -2510A/G promoter polymorphism was statistically higher than that of subjects with the non-G carrier (161.5+/-48.3 pg/mL). The luciferase activity was significantly greater from interleukin (IL)-1beta-induced cells transfected with constructs containing G at position -2510.

CONCLUSIONS

The G carrier of the -2510A/G promoter polymorphism was found to be associated with primary knee OA, and could be a susceptibility factor in the development of primary knee OA in the Korean population.

Anti-inflammatory effects of an ethanolic extract from Clematis mandshurica Rupr

Clematis mandshurica Rupr (Ranunculaceae) roots are used in traditional Korean medicine to treat inflammation-related diseases. Therefore, we undertook to investigate their inhibitory effect on inflammation under non-cytotoxic conditions. The ethanolic extract of Clematis mandshurica at 100 microg/ml was found to significantly block the production of the pro-inflammatory mediators, nitric oxide (NO) and prostaglandin E(2) (PGE(2)), in lipopolysaccharide (LPS)/interferon(IFN)-gamma-stimulated mouse peritoneal macrophages, by up to 77% and 59%, respectively. In addition, it significantly inhibited cell proliferation and cytokine production (interleukin (IL)-2 and IFN-gamma) in splenocytes stimulated with Con A (concanavalin A; 5 microg/ml). Furthermore, when splenocytes from extract fed mice (200 mg/kg for 2 weeks) were activated with Con A, cell proliferation and the production of IL-2 and IFN-gamma were significantly inhibited. In addition, the extract reduced in vivo inflammation in oxazolone-induced delayed type hypersensitivity (DTH) model mice. Taken together, these data suggest that Clematis mandshurica is able to ameliorate inflammatory disease by exerting an anti-inflammatory effect in cases of proinflammatory and cell-mediated inflammation.

Rising number of tuberculosis cases among Tibetans in New York City

Tuberculosis among Tibetans increased in New York City between 1995 and 1999. We examined characteristics of 68 Tibetan patients compared to 702 non-Tibetan patients from Nepal, India, or China, diagnosed between January 1995 and December 1999. The number of Tibetan patients increased each year after 1995 whereas non-Tibetans remained stable during the same period. Tibetans were younger (27 vs. 44 years), more likely to be infectious (63% vs. 46%), have multidrug resistance (7% vs. 2%) and shorter time to diagnosis after arrival (9 vs. 79 months, p < 0.01). For Tibetan patients, 68% of identified contacts were evaluated. The prevalence of tuberculosis infection was 65%. In contrast, among non-Tibetan patients 88.8% of contacts were evaluated and 45.2% were infected. Outreach efforts with community leaders and educational presentations at community events have been implemented in an effort to ensure continuity of care and completion of treatment.

First report of Cryptococcus albidus--induced disseminated cryptococcosis in a renal transplant recipient

Cryptococcus albidus, a non-neoformans species of the genus Cryptococcus, is generally regarded as a rare cause of disease. There have been only 14 previously reported cases in which this organism has been isolated as a pathogen, none of which occurred in a renal transplant recipient. A 23-year-old renal transplant recipient taking medication consisting of cyclosporine and prednisolone was admitted with a 10-day history of dry cough, fever and progressive dyspnea. The next day, his respiratory status deteriorated dramatically, and he developed acute respiratory distress syndrome (ARDS) and fulminant septic shock. On the eighth hospital day, tender macules on both his shins coalesced to form erythematous patches. Cryptococcus albidus was isolated by skin biopsy and tissue culture. We report here the first case of disseminated cryptococcosis caused by C. albidus in a renal transplant recipient who had been successfully treated with fluconazole monotherapy.

Ganglioneuroblastoma presenting as dilated cardiomyopathy

We report an unusual presentation of ganglioneuroblastoma with features of dilated cardiomyopathy in a 22 month old girl. She was admitted with cardiomegaly; during echocardiography a suspicious abdominal mass was detected by chance. Further imaging studies, including abdominal ultrasonography and spiral computed tomography, revealed a solid mass originating in the right adrenal gland. Metabolic studies and pathological findings were compatible with ganglioneuroblastoma. Following tumour removal and supportive therapy for cardiomyopathy, her clinical condition and laboratory findings improved. Although ganglioneuroblastoma with features of dilated cardiomyopathy is rare, because neurogenic tumours may be involved in its development, measurement of catecholamines in children with dilated cardiomyopathy is strongly recommended.

Isolation of an insertion sequence from Ralstonia solanacearum race 1 and its potential use for strain characterization and detection

A new insertion sequence (IS), IS1405, was isolated and characterized from a Ralstonia solanacearum race 1 strain by the method of insertional inactivation of the sacB gene. Sequence analysis indicated that the IS is closely related to the members of IS5 family, but the extent of nucleotide sequence identity in 5' and 3' noncoding regions between IS1405 and other members of IS5 family is only 23 to 31%. Nucleotide sequences of these regions were used to design specific oligonucleotide primers for detection of race 1 strains by PCR. The PCR amplified a specific DNA fragment for all R. solanacearum race 1 strains tested, and no amplification was observed with some other plant-pathogenic bacteria. Analysis of nucleotide sequences flanking IS1405 and additional five endogenous IS1405s that reside in the chromosome of R. solanacearum race 1 strains indicated that IS1405 prefers a target site of CTAR and has two different insertional orientations with respect to this target site. Restriction fragment length polymorphism (RFLP) pattern analysis using IS1405 as a probe revealed extensive genetic variation among strains of R. solanacearum race 1 isolated from eight different host plants in Taiwan. The RFLP patterns were then used to subdivide the race 1 strains into two groups and several subgroups, which allowed for tracking different subgroup strains of R. solanacearum through a host plant community. Furthermore, specific insertion sites of IS1405 in certain subgroups were used as a genetic marker to develop subgroup-specific primers for detection of R. solanacearum, and thus, the subgroup strains can be easily identified through a rapid PCR assay rather than RFLP analysis.

Mutations in CAV3 cause mechanical hyperirritability of skeletal muscle in rippling muscle disease

Hereditary rippling muscle disease (RMD) is an autosomal dominant human disorder characterized by mechanically triggered contractions of skeletal muscle. Genome-wide linkage analysis has identified an RMD locus on chromosome 3p25. We found missense mutations in positional candidate CAV3 (encoding caveolin 3; ref. 5) in all five families analyzed. Mutations in CAV3 have also been described in limb-girdle muscular dystrophy type 1C (LGMD1C; refs. 6,7), demonstrating the allelism of dystrophic and non-dystrophic muscle diseases.

Localisation of a gene for an autosomal recessive syndrome of macrocephaly, multiple epiphyseal dysplasia, and distinctive facies to chromosome 15q26

BACKGROUND

We have previously described an autosomal recessive syndrome of macrocephaly, multiple epiphyseal dysplasia (MED), and distinctive facies in a large, extended Omani family. The MED observed seems to be part of a larger malformation syndrome, since both craniofacial and central nervous system changes were present in the family. We performed a whole genome scan in this family in order to identify the gene locus for this malformation syndrome.

METHODS AND RESULTS

Using homozygosity mapping, we show linkage to the telomeric region of the long arm of chromosome 15. The position of both the disease gene and the principal glycoprotein, chondroitin sulphate proteoglycan (aggrecan, AGC1) on chromosome 15q26, suggested that the aggrecan gene is a candidate for the disease in this family. However, three of the four affected children were heterozygous for a polymorphism at position 831 of the coding sequence of AGC1, providing strong evidence against its involvement.

CONCLUSION

We have identified a gene locus for a recessive syndrome of macrocephaly, MED, and distinctive facies in a large Omani family. Aggrecan located on chromosome 15q26, within the critical region determined for this syndrome in this family, was excluded as a candidate gene.

Structures and related properties of AgX bearing 3,3'-thiobispyridine (X- = NO3-, BF4-, CLO4-, and PF6-

Infinite molecular helices [Ag(3,3'-Py2S)]X (3,3'-Py2S = 3,3'-thiobispyridine; X- = BF4-, ClO4-, and PF6-) have been rationally constructed or induced. Crystallographic characterization (X- = BF-, monoclinic P2(1)/n, a = 8.946(3) A, b = 14.130(2) A, c = 10.124(2) A, beta = 107.83(2) degrees, V = 1218.3(5) A3, Z = 4, R = 0.0351; X- = ClO4-, monoclinic P2(1)/n, a = 8.884(1) A, b = 14.305(3) A, c = 10.110(1) A, beta = 106.78(1) degrees, V = 1230.1(3) A3, Z = 4, R = 0.0417; X- = PF6-, monoclinic P2(1)/c, a = 10.959(2) A, b = 9.808(2) A, c = 14.065(3) A, beta = 112.03(2) degrees, V = 1401.4(5) A3, Z = 4, R = 0.0442) reveals that the skeletal structure is an oblong cylindrical cationic helix consisting of alternating Ag(I) and 3,3'-Py2S species and that its counteranions are pinched in two columns inside each helix. The formation of the helical coordination polymer appears to be primarily associated with a suitable combination of the skewed conformer of 3,3'-Py2S and the potential linear geometry of the N-Ag(I)-N bond. However, the framework of the nitrate analogue [Ag(3,3'-Py2S)NO3] (monoclinic P2(1)/c, a = 8.177(2) A, b = 10.291(1) A, c = 14.771(2) A, beta = 102.19(1) degrees, V = 1214.9(4) A3, Z = 4, R = 0.0300) is a two-dimensional network consisting of an 18-membered ring unit, where each 3,3'-Py2S acts as a N,N',S- tridentate ligand connecting three tetrahedral silver(I) ions with the monodentate nitrate weakly bonded to the silver (Ag.O = 2.65(1) A) rather than acting as a counteranion. The anion exchange of [Ag(3,3'-Py2S)NO3] with BF4-, ClO4-, or PF6- has been accomplished in aqueous media. The two-dimensional networks are easily converted into the helices via the anion exchange, but the reverse anion exchange proceeds slightly. Thermal analyses indicate a relationship between the thermal stabilities and the structural properties.

A major susceptibility locus for atopic dermatitis maps to chromosome 3q21

Atopic dermatitis (eczema) is a chronic inflammatory skin disease with onset mainly in early childhood It is commonly the initial clinical manifestation of allergic disease, often preceding the onset of respiratory allergies. Along with asthma and allergic rhinitis, atopic dermatitis is an important manifestation of atopy that is characterized by the formation of allergy antibodies (IgE) to environmental allergens. In the developed countries, the prevalence of atopic dermatitis is approximately 15%, with a steady increase over the past decades. Genetic and environmental factors interact to determine disease susceptibility and expression, and twin studies indicate that the genetic contribution is substantial. To identify susceptibility loci for atopic dermatitis, we ascertained 199 families with at least two affected siblings based on established diagnostic criteria. A genome-wide linkage study revealed highly significant evidence for linkage on chromosome 3q21 (Zall=4.31, P= 8.42 10(-6)). Moreover, this locus provided significant evidence for linkage of allergic sensitization under the assumption of paternal imprinting (hlod=3.71,alpha=44%), further supporting the presence of an atopy gene in this region. Our findings indicate that distinct genetic factors contribute to susceptibility to atopic dermatitis and that the study of this disease opens new avenues to dissect the genetics of atopy.

The effects of skin pressure by clothing on circadian rhythms of core temperature and salivary melatonin

The present experiment investigated the effects of skin pressure by foundation garments (girdle and brassiere) on the circadian rhythms of core temperature and salivary melatonin. Ten healthy females (18-23 years) maintained regular sleep-wake cycles for a week prior to participation in the experiment. The experiments were performed from June to August 1999 using a bioclimatic chamber controlled at 26.5 degrees C +/- 0.2 degrees C and 62% +/- 3% RH. Ambient light intensity was controlled at 500 lux from 07:30 to 17:30, 100 lux from 17:30 to 19:30, 20 lux from 19:30 to 23:30; there was total darkness from 23:30 to 07:30. The experiment lasted for 58h over three nights. The participants arose at 07:30 on the first full day and retired at 23:30, adhering to a set schedule for 24h, but without wearing foundation garments. For the final 24h of the second full day, the subjects wore foundation garments. Rectal and leg skin temperatures were measured continuously throughout the experiment. Saliva and urine were collected every 4h for the analysis of melatonin and catecholamines, respectively. Skin pressure applied by the foundation garments was in the range 11-17 gf/cm2 at the regions of the abdomen, hip, chest, and back. The main results were as follows: (1) Rectal temperatures were significantly higher throughout the day and night when wearing foundation garments. (2) The nocturnal level of salivary melatonin measured at 03:30 was 115.2 +/- 40.4 pg/mL (mean +/- SEM, N = 10) without and 51.3 +/- 18.4 pg/mL (mean +/- SEM, N = 10) with foundation garments. (3) Mean urinary noradrenaline excretion was significantly lower throughout the day and night when wearing foundation garments (p < .05), but mean urinary adrenaline excretion was not different. The results suggest that skin pressure by clothing could markedly suppress the nocturnal elevation of salivary melatonin, resulting in an increase of rectal temperature.

Antioxidative phenolic compounds from the roots of Rhodiola sachalinensis A. Bor

The acetone extract of the roots of Rhodiola sachalinensis has furnished six phenolic compounds which exhibited significant scavenging effects against DPPH free radical. The structures of these compounds were identified and determined as gallic acid (1), (-)-epigallocatechin 3-O-gallate (2), kaempferol (3), kaempferol 7-O-alpha-L-rhamnopyranoside (4), herbacetin 7-O-alpha-L-rhamnopyranoside, (5) and rhodiolinin (6) by physico-chemical and spectral evidences.

Field studies on inhibitory influence of skin pressure exerted by a body compensatory brassiere on the amount of feces

The present experiment investigated the effects of skin pressure produced by a body compensatory brassiere on defecation activity. Seven healthy females (11-41 yrs) volunteered as participants, being free of medication and constipation. The experiment lasted 3 weeks. The participants did not wear the body compensatory brassiere for the first week, wore it during waking hours for the second week, and again did not wear it for the third week. Whenever they desired to defecate, they did so and then weighted the amount of feces immediately by themselves. Eating times, daily amounts of foods and drinks, their menu, work intensity and its duration, retiring and rising time were controlled to be as similar as possible from day to day. The main finding was that the amount of feces was significantly smaller during the second week (wearing the body compensatory brassiere) than the first and third weeks (not wearing the body compensatory brassiere). These observations are discussed in terms of the suppression of the parasympathetic nervous system and intestine motility, and the delayed transit time in the large intestine.

A gene for hypotrichosis simplex of the scalp maps to chromosome 6p21.3

Hypotrichosis simplex of the scalp (HSS) is an autosomal dominant form of isolated alopecia causing almost complete loss of scalp hair, with onset in childhood. After exclusion of candidate regions previously associated with hair-loss disorders, we performed a genomewide linkage analysis in two Danish families and localized the gene to chromosome 6p21.3. This was confirmed in a Spanish family, with a total LOD score of 11.97 for marker D6S1701 in all families. The combined haplotype data identify a critical interval of 14.9 cM between markers D6S276 and D6S1607. Localization of the locus for HSS to 6p21.3 is a first step toward identification of the gene. The gene will give important insights into the molecular and cellular basis of hair growth on the scalp.

Synthesis and oral antitumor activity of tetrakis(carboxylato)platinum(IV) complexes

A novel class of tetrakis(carboxylato)platinum(IV) complexes, [Pt(O(2)CR)(4)(dach)] (dach = trans-(+/-)-1,2-diaminocyclohexane; R = C(n)H(2n+1), n = 1 approximately 5), was synthesized and studied for physicochemical properties and oral antitumor activity. Lipophilicity and aqueous solubility of the title complexes were greatly dependent on the alkyl chain length of the carboxylate ligand, and their partition coefficient and solubility changed by 4 or 5 orders of magnitude from acetate to hexanoate complexes. On the other hand, the range of their cathodic reduction potential (-546 approximately -403 mV) depending on the chain length of the carboxylate ligand was relatively small. Among the title complexes, the tetrakis(propionato)platinum(IV) complex, [Pt(O(2)CC(2)H(5))(4)(dach)], with appropriate lipophilicity (log P = 0.18) and aqueous solubility (14.6 mg/mL) was found to exhibit better oral antitumor activity than JM216 against the human ovarian tumor xenograft SKOV3 in nude mice.

A gene involved in quinate metabolism is specific to one DNA homology group of Xanthomonas campestris

A gene involved in quinate metabolism was cloned from Xanthomonas campestris pv. juglandis strain C5. The gene, qumA, located on a 4. 2-kb KpnI-EcoRV fragment in plasmid pQM38, conferred quinate metabolic activity to X. c. pv. celebensis. Tn3-spice insertional analyses further located the qumA gene on a region of about 3.0 kb within pQM38. Nucleotide sequencing of this 3.0-kb fragment reveals that the coding region of qumA is 2373 bp, the deduced amino acid sequence of which closely resembles a pyrrolo-quinoline quinone-dependent quinate dehydrogenase of Acinetobacter calcoaceticus. A 0.7 kb SalI-PstI fragment internal to qumA was used as a probe to hybridize against total genomic DNA from 43 pathovars of X. campestris. The fragment hybridized only to total genomic DNA from the four pathovars of DNA homology group 6, X. c. pv. celebensis, X. c. pv. corylina, X. c. pv. juglandis and X. c. pv. pruni, and from X. c. pv. carotae, which belongs to DNA homology group 5. This 0.7 kb fragment was also used as a probe to hybridize BamHI-digested total genomic DNAs from the four pathovars of DNA homology group 6 and X. c. pv. carotae. The restriction fragment length polymorphism pattern of DNA homology group 6 was different from that of X. c. pv. carotae. The probe hybridized to a 5.7-kb BamHI fragment in all four pathovars of group 6 and to a 6.1-kb BamHI fragment in three of four pathovars. It hybridized only to a 9. 9-kb BamHI fragment in X. c. pv. carotae. Quinate metabolism has previously been reported as a phenotypic property specific to X. campestris DNA homology group 6. Accordingly, a combination of the quinate metabolism phenotypic test and Southern hybridization using a qumA-derived probe will be very useful in the identification of pathovars in DNA homology group 6.

Congenic substitution mapping excludes Sa as a candidate gene locus for a blood pressure quantitative trait locus on rat chromosome 1

Previously, linkage analysis in several experimental crosses between hypertensive rat strains and their contrasting reference strains have identified a major quantitative trait locus (QTL) for blood pressure on rat chromosome 1 (Chr 1) spanning the Sa gene locus. In this study, we report the further dissection of this Chr 1 blood pressure QTL with congenic substitution mapping. To address whether the Sa gene represents a candidate gene for the Chr 1 blood pressure QTL, congenic strains were developed by introgressing high blood pressure QTL alleles from the stroke-prone spontaneously hypertensive rat (SHRSP) into the normotensive Wistar-Kyoto (WKY-1) reference strain. Congenic animals carrying a chromosomal segment from stroke-prone spontaneously hypertensive rats between genetic markers Mt1pa and D1Rat200 (including the Sa gene locus) show a significant increase in basal systolic and diastolic blood pressure compared with their normotensive Wistar-Kyoto progenitors (P<0.001, respectively), whereas congenic animals carrying a subfragment of this Chr 1 region defined by markers Mt1pa and D1Rat57 (also spanning the Sa gene) do not show elevated basal blood pressure levels (P=0.83 and P=0.9, respectively). Similar results were obtained for NaCl-induced blood pressure values. Thus, the blood pressure QTL on Chr 1 is located centromeric to the Sa gene locus in a region that is syntenic to human chromosome 11p15.4-p15.3. This region excludes the Sa as a blood pressure-elevating candidate gene locus on the basis of congenic substitution mapping approaches.

Activation of phonological codes during eye fixations in reading

Two experiments addressed the issue of whether phonological codes are activated early in a fixation during reading using the fast-priming technique (S. C. Sereno & K. Rayner, 1992). Participants read sentences and, at the beginning of the initial fixation in a target location, a priming letter string was displayed, followed by the target word. Phonological priming was assessed by the difference in the gaze duration on the target word between when the prime was a homophone and when it was a control word equated with the homophone on orthographic similarity to the target. Both experiments demonstrated homophonic priming with prime durations of about 35 ms, but only for high-frequency word primes, indicating that lexicality was guiding the speed of the extraction of phonological codes early in a fixation. Evidence was also obtained for orthographic priming, and the data suggest that orthographic and phonological priming effects interact in a mutually facilitating manner.

Activation of phonological codes during eye fixations in reading

Two experiments addressed the issue of whether phonological codes are activated early in a fixation during reading using the fast-priming technique (S. C. Sereno & K. Rayner, 1992). Participants read sentences and, at the beginning of the initial fixation in a target location, a priming letter string was displayed, followed by the target word. Phonological priming was assessed by the difference in the gaze duration on the target word between when the prime was a homophone and when it was a control word equated with the homophone on orthographic similarity to the target. Both experiments demonstrated homophonic priming with prime durations of about 35 ms, but only for high-frequency word primes, indicating that lexicality was guiding the speed of the extraction of phonological codes early in a fixation. Evidence was also obtained for orthographic priming, and the data suggest that orthographic and phonological priming effects interact in a mutually facilitating manner.

Synthesis and antiviral activity of apio dideoxy nucleosides with azido or amino substituent

Novel apio dideoxynucleosides with azido or amino or amino substituent were synthesized starting from 1,3-dihydroxyacetone utilizing an acid-catalyzed 1,4-conjugated addition as a key step and evaluated for antiviral activity. Unfortunately, they were found to be neither active against HIV-1, HSV-1,2 and poliovirus nor toxic.

Synthesis and antitumor activity of (diamine)platinum(II) complexes of benzylmalonate derivatives

(Diamine)platinum(II) complexes of benzylmalonate derivatives as a leaving group designed in a wide range of lipophilicity and water-solubility were prepared and their antitumor activities were attempted to correlate to their lipophilicity or solubility. A good relationship was observed between their in vitro toxicity and solubility of the title complexes with the same carrier ligand, DACH (trans-(+/-)-1,2-diaminocyclohexane): The most soluble complexes are most cytotoxic whereas the least soluble complexes are least cytotoxic. However, no relationship could be established between their in vivo activity and their lipophilicity or solubility presumably due to other pharmacokinetic factors involved in vivo. The molecular structure of (IPA)2Pt(DBM).2CH3OH (IPA = isopropylamine; DBM = dibenzylmalonate) was determined by X-ray diffraction: space group P2(1)/n, a = 11.433 (3), b = 14.461 (4), c = 17.478 (4) A, beta = 97.25 (3) degrees, z = 4, R = 0.0437.

Tissue- and development-specific expression of multiple alternatively spliced transcripts of rat neuronal nitric oxide synthase

Nitric oxide (NO) functions as an intercellular messenger and mediates numerous biological functions. Among the three isoforms of NO synthase that produce NO, the ubiquitously expressed neuronal NO synthase (nNOS) is responsible for a large part of NO production, yet its regulation is poorly understood. Recent reports of two alternative spliceforms of nNOS in the mouse and in man have raised the possibility of spatial and temporal modulation of expression. This study demonstrates the existence of at least three transcripts of the rat nNOS gene designated nNOSa, nNOSb, and nNOSc, respectively, with distinct 5' untranslated first exons that arise from alternative splicing to a common second exon. Expression of the alternative transcripts occurs with a high degree of tissue and developmental specificity, as demonstrated by RNase protection assays on multiple tissues from both fetal and adult rats. Furthermore, terminal differentiation of rat pheochromocytoma-derived PC12 cells into neurons is associated with induction of nNOSa, suggesting, likewise, development- and tissue-specific transcriptional control of nNOS isoform expression. Physical mapping using a rat yeast artificial chromosome clone shows that the alternatively spliced first exons 1a, 1b, and 1c are separated by at least 15-60 kb from the downstream coding sequence, with exons 1b and 1c being positioned within 200 bp of each other. These findings provide evidence that the biological activity of nNOS is tightly and specifically regulated by a complex pattern of alternative splicing, indicating that the notion of constitutive expression of this isoform needs to be revised.

Möbius syndrome with brain stem calcification: prenatal and neonatal sonographic findings

The sonographic findings of Möbius syndrome with brain stem calcification are presented. Prenatal and neonatal sonography disclosed characteristic hyperechoic dots or linear bands in the brain stem representing calcification, which suggests prenatal ischemic insult to the brain stem.

Local stress, not systemic factors, regulate gene expression of the cardiac renin-angiotensin system in vivo: a comprehensive study of all its components in the dog

Cardiac hypertrophy is associated with altered expression of the components of the cardiac renin-angiotensin system (RAS). While in vitro data suggest that local mechanical stimuli serve as important regulatory modulators of cardiac RAS activity, no in vivo studies have so far corroborated these observations. The aims of this study were to (i) examine the respective influence of local, mechanical versus systemic, soluble factors on the modulation of cardiac RAS gene expression in vivo; (ii) measure gene expression of all known components of the RAS simultaneously; and (iii) establish sequence information and an assay system for the RAS of the dog, one of the most important model organisms in cardiovascular research. We therefore examined a canine model of right ventricular hypertrophy and failure (RVHF) in which the right ventricle (RV) is hemodynamically loaded, the left ventricle (LV) is hemodynamically unloaded, while both are exposed to the same circulating milieu of soluble factors. Using specific competitive PCR assays, we found that RVHF was associated with significant increases in RV mRNA levels of angiotensin converting enzyme and angiotensin II type 2 receptor, and with significant decreases of RV expression of chymase and the angiotensin II type 1 receptor, while RV angiotensinogen and renin remained unchanged. All components remained unchanged in the LV. We conclude that (i) dissociated regional regulation of RAS components in RV and LV indicates modulation by local, mechanical, not soluble, systemic stimuli; (ii) components of the cardiac RAS are independently and differentially regulated; and (iii) opposite changes in the expression of angiotensin converting enzyme and chymase, and of angiotensin II type I and angiotensin II type 2 receptors, may indicate different physiological roles of these RAS components in RVHF.

Mobile cecum syndrome: a report of two cases

Mobile cecum syndrome is characterized by chronic right lower quadrant pain with the evidence of neither appendicitis nor other pathological findings at operation. Two cases of mobile cecum syndrome are reported; both had intermittent right lower quadrant cramping pain for months. One had received appendectomy because of chronic right lower quadrant pain at another hospital about nine months before admission here. The symptoms did not improve postoperatively, and the patient underwent laparotomy under impression of partial intestinal obstruction. The other patient underwent laparotomy under impression of chronic appendicitis. At surgery, both were found to have cecum and ascending colon were not attached to the posterior parietal wall, and cecopexy was performed. They have now been symptom free for one year. Cecopexy appears therefore to be an effective method of treatment of mobile cecum syndrome.

The cardiac renin-angiotensin-aldosterone system and hypertensive cardiac hypertrophy

Angiotensin-converting enzyme inhibitors have proven to be uniquely effective in inducing regression, or preventing the occurrence, of ventricular hypertrophy associated with systemic hypertension. This has pointed, for many years, to a possible direct involvement of the renin-angiotensin system in the pathogenesis of cardiac hypertrophy. Over the last 10 years further supporting evidence has been forthcoming about direct trophic effects of angiotensin II in several experimental systems. Additionally, we now have rather conclusive evidence for the existence of a local, intracardiac renin-angiotensin system, which is capable of synthesis of all components of the system, and of cleaving, via the classic pathway, angiotensin peptides from the precursor, angiotensinogen. Moreover, a number of studies have demonstrated the capacity of regulatory response and modulation of activity of the local system in response to a variety of pharmacologic perturbations as well as differential expression of specific components under pathologic conditions, including compensatory hypertrophy and remodeling after myocardial infarction, pressure overload hypertrophy, and volume overload hypertrophy. Continued research into the role of the cardiac renin-angiotensin system in the pathogenesis of cardiac hypertrophy and failure will provide us with the tools to devise more specific, targeted strategies for therapeutic intervention or prevention.

An immunohistochemical analysis of mdr-1 and bcl-2 expressions in neuroblastoma

Among the differentiation-related changes in neuroblastoma are expressions of mdr-1 and bcl-2, which may be potentially related to the resistance to anticancer chemotherapy. In the present study, the authors performed an immunohistochemical analysis of mdr-1 and bcl-2 expressions in 30 neuroblastomas using monoclonal anti-P-glycoprotein(mdr-1 product) antibody and monoclonal anti-bcl-2 antibody to investigate the significance of their expression. The overall incidence of mdr-1 and bcl-2 expressions were 53.3% (16/30) and 93.3% (28/30), respectively. The expressions of mdr-1 and bcl-2 didn't seem to be related to the status of preoperative chemotherapy or stage of disease. The expression of mdr-1 was closely related to the differentiation of tumor cells (p < 0.01), especially to the neuronal differentiation. The bcl-2 expression was so common that it seemed to be indigenous to this neoplasm. The overall findings suggested that the expression of mdr-1 is one of the differentiation markers, while bcl-2 expression may partly explain the reasons for the relatively poor prognosis of neuroblastoma by the resistance to anticancer chemotherapy, which is a major therapeutic tool for this peculiar neoplasm.

Bcl-2 expression in neuroblastoma is differentially regulated by differentiation inducers

Neuroblastoma is characterized by differentiation in vivo and in vitro, and the process is known to be associated with changes in various gene expressions, among which is the bcl-2 gene whose major function may be potentially involved in the resistance to anticancer chemotherapy. We investigated the changing patterns of bcl-2 expression in neuroblastoma cell lines according to differentiation to assess whether the expression patterns can be differentially modulated by different types of differentiation inducers. Differentiation was induced in two neuroblastoma cell lines [SK-N-SH, SK-N-BE(2)] using all-trans-retinoic acid, gamma-interferon and EHS laminin, respectively. The levels of expression of bcl-2 were analysed before and after differentiation using immunoblotting and subsequent densitometry. The expression patterns of bcl-2 differed according to the type of differentiation inducers. Its expression increased when treated with retinoic acid and EHS laminin along with neuronal differentiation, while differentiation with gamma-interferon treatment was associated with decreased bcl-2 expression. Decreased expression of bcl-2 despite neuronal differentiation induced by gamma-interferon was thought to be important in that a certain differentiation pathway without increased drug resistance-related factor expression exists, which in turn has implications for the clinical application of gamma-interferon, combined with chemotherapy.